NASA Technical Reports Server (NTRS)
Russell, Philip B.
1994-01-01
Many theoretical studies have shown that anthropogenic aerosol particles can change the radiation balance in an atmospheric column and might thereby exert a significant effect on the Earth's climate. In particular, recent calculations have shown that sulfate particles from anthropogenic combustion may already exert a cooling influence on the Earth that partially offsets the warming caused by the greenhouse gases from the same combustion. Despite the potential climatic importance of anthropogenic aerosols, simultaneous measurements of anthropogenic aerosol properties and their effect on atmospheric radiation have been very rare. Successful comparisons of measured radiation fields with those calculated from aerosol measurements - now referred to as column closure comparisons - are required to improve the accuracy and credibility of climate predictions. This paper reviews the column closure experiment performed at the Mt. Sutro Tower in San Francisco in 1975, in which elevated radiometers measured the change in Earth-plus-atmosphere albedo caused by an aerosol layer, while a lidar, sunphotometer, nephelometer, and other radiometers measured properties of the responsible aerosol. The time-dependent albedo calculated from the measured aerosol properties agreed with that measured by the tower radiometers. Also presented are designs for future column closure studies using radiometers and aerosol instruments on the ground, aircraft, and satellites. These designs draw upon algorithms and experience developed in the Sutro Tower study, as well as more recent experience with current measurement and analysis capabilities.
Pan, Wenxiao; Galvin, Janine; Huang, Wei Ling; ...
2018-03-25
In this paper we aim to develop a validated device-scale CFD model that can predict quantitatively both hydrodynamics and CO 2 capture efficiency for an amine-based solvent absorber column with random Pall ring packing. A Eulerian porous-media approach and a two-fluid model were employed, in which the momentum and mass transfer equations were closed by literature-based empirical closure models. We proposed a hierarchical approach for calibrating the parameters in the closure models to make them accurate for the packed column. Specifically, a parameter for momentum transfer in the closure was first calibrated based on data from a single experiment. Withmore » this calibrated parameter, a parameter in the closure for mass transfer was next calibrated under a single operating condition. Last, the closure of the wetting area was calibrated for each gas velocity at three different liquid flow rates. For each calibration, cross validations were pursued using the experimental data under operating conditions different from those used for calibrations. This hierarchical approach can be generally applied to develop validated device-scale CFD models for different absorption columns.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pan, Wenxiao; Galvin, Janine; Huang, Wei Ling
In this paper we aim to develop a validated device-scale CFD model that can predict quantitatively both hydrodynamics and CO 2 capture efficiency for an amine-based solvent absorber column with random Pall ring packing. A Eulerian porous-media approach and a two-fluid model were employed, in which the momentum and mass transfer equations were closed by literature-based empirical closure models. We proposed a hierarchical approach for calibrating the parameters in the closure models to make them accurate for the packed column. Specifically, a parameter for momentum transfer in the closure was first calibrated based on data from a single experiment. Withmore » this calibrated parameter, a parameter in the closure for mass transfer was next calibrated under a single operating condition. Last, the closure of the wetting area was calibrated for each gas velocity at three different liquid flow rates. For each calibration, cross validations were pursued using the experimental data under operating conditions different from those used for calibrations. This hierarchical approach can be generally applied to develop validated device-scale CFD models for different absorption columns.« less
NASA Technical Reports Server (NTRS)
Schmid, Beat; Russell, Philip B.; Livingston, John M.; Gasso, Santiago; Hegg, Dean A.; Collins, Donald R.; Flagan, Richard C.; Seinfeld, John H.; Oestroem, Elisabeth; Noone, Kevin J.;
2000-01-01
As part of the second Aerosol Characterization Experiment (ACE-2), European urban-marine and African mineral-dust aerosols were measured aboard the Pelican aircraft, the Research Vessel Vodyanitskiy from the ground and from satellites.
P. W. Garrett; W. K. Randall; A. L. Shigo; W. C. Shortle
1979-01-01
Studies of half-sib progeny tests of sweetgum (Liquidambar styraciflua) and clonal plantings of eastern cottonwood (Populus deltoides) in Mississippi indicate that rate of wound closure and size of discolored columns associated with the wounds are both heritable traits. Both are independent of stem diameter, which was used as a...
Cavitating flow during water hammer using a generalized interface vaporous cavitation model
NASA Astrophysics Data System (ADS)
Sadafi, Mohamadhosein; Riasi, Alireza; Nourbakhsh, Seyed Ahmad
2012-10-01
In a transient flow simulation, column separation may occur when the calculated pressure head decreases to the saturated vapor pressure head in a computational grid. Abrupt valve closure or pump failure can result in a fast transient flow with column separation, potentially causing problems such as pipe failure, hydraulic equipment damage, cavitation or corrosion. This paper reports a numerical study of water hammer with column separation in a simple reservoir-pipeline-valve system and pumping station. The governing equations for two-phase transient flow in pipes are solved based on the method of characteristics (MOC) using a generalized interface vaporous cavitating model (GIVCM). The numerical results were compared with the experimental data for validation purposes, and the comparison indicated that the GIVCM describes the experimental results more accurately than the discrete vapor cavity model (DVCM). In particular, the GIVCM correlated better with the experimental data than the DVCM in terms of timing and pressure magnitude. The effects of geometric and hydraulic parameters on flow behavior in a pumping station with column separation were also investigated in this study.
Seismic-Resistant Connections between Precast Concrete Columns and Drilled Shafts
DOT National Transportation Integrated Search
2012-06-01
In most areas of the country traffic is becoming more congested, and delays, more common. Highway construction, and especially construction that requires lane closures, exacerbates the delays, and imposes costs that can be measured in dollars, wasted...
Rupture loop annex ion exchange RLAIX vault deactivation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ham, J.E.; Harris, D.L., Westinghouse Hanford
This engineering report documents the deactivation, stabilization and final conditions of the Rupture Loop Annex Ion Exchange (RLAIX) Vault located northwest of the 309 Building`s Plutonium Recycle Test Reactor (PRTR). Twelve ion exchange columns, piping debris, and column liquid were removed from the vault, packaged and shipped for disposal. The vault walls and floor were decontaminated, and portions of the vault were painted to fix loose contamination. Process piping and drains were plugged, and the cover blocks and rain cover were installed. Upon closure,the vault was empty, stabilized, isolated.
Studies of Weak, ELF Electromagnetic Fields Effects on the Early Embryonic Development
1988-12-29
characters: - General aspect: stage; size of the embryo; size of the head relatively to the trunk. - Head : morphology of the skull; development of...the eyes; size and morphology of the beak; size of the neck . - Trunk: morphology of the vertebral column; development of the tail; closure of thorax and...mishandled, the orientation of the embryo was not taken into account. As indicated in Fig. 7, the head -tail axis orientation of an embryo was North (N
Gas arc constriction for plasma arc welding
NASA Technical Reports Server (NTRS)
McGee, William F. (Inventor); Rybicki, Daniel J. (Inventor)
1994-01-01
A welding torch for plasma arc welding apparatus has an inert gas applied circumferentially about the arc column externally of the constricting nozzle so as to apply a constricting force on the arc after it has exited the nozzle orifice and downstream of the auxiliary shielding gas. The constricting inert gas is supplied to a plenum chamber about the body of the torch and exits through a series of circumferentially disposed orifices in an annular wall forming a closure at the forward end of the constricting gas plenum chamber. The constricting force of the circumferential gas flow about the arc concentrates and focuses the arc column into a more narrow and dense column of energy after exiting the nozzle orifice so that the arc better retains its energy density prior to contacting the workpiece.
NASA Technical Reports Server (NTRS)
Clarke, Antony D.; Porter, John N.
1997-01-01
Our research effort is focused on improving our understanding of aerosol properties needed for optical models for remote marine regions. This includes in-situ and vertical column optical closure and involves a redundancy of approaches to measure and model optical properties that must be self consistent. The model is based upon measured in-situ aerosol properties and will be tested and constrained by the vertically measured spectral differential optical depth of the marine boundary layer, MBL. Both measured and modeled column optical properties for the boundary layer, when added to the free-troposphere and stratospheric optical depth, will be used to establish spectral optical depth over the entire atmospheric column for comparison to and validation of satellite derived radiances (AVHRR).
NASA Technical Reports Server (NTRS)
Schmid, Beat; Livingston, John M.; Russell, Philip B.; Durkee, Philip A.; Jonsson, Haflidi H.; Collins, Donald R.; Flagan, Richard C.; Seinfeld, John H.; Gasso, Santiago; Hegg, Dean A.;
2000-01-01
We report on clear-sky column closure experiments (CLEARCOLUMN) performed in the Canary Islands during the second Aerosol Characterization Experiment (ACE-2) in June/July 1997. We present CLEARCOLUMN results obtained by combining airborne sunphotometer and in-situ (optical particle counter, nephelometer, and absorption photometer) measurements taken aboard the Pelican aircraft, space-borne NOAA/AVHRR data and ground-based lidar and sunphotometer measurements. During both days discussed here, vertical profiles flown in cloud-free air masses revealed 3 distinctly different layers: a marine boundary layer (MBL) with varying pollution levels, an elevated dust layer, and a very clean layer between the MBL and the dust layer. A key result of this study is the achievement of closure between extinction or layer aerosol optical depth (AOD) computed from continuous in-situ aerosol size-distributions and composition and those measured with the airborne sunphotometer. In the dust, the agreement in layer AOD (lambda = 380-1060 nm) is 3-8%. In the MBL there is a tendency for the in-situ results to be slightly lower than the sunphotometer measurements (10-17% at lambda = 525 nm), but these differences are within the combined error bars of the measurements and computations.
NASA Astrophysics Data System (ADS)
Tan, Z.; Schneider, T.; Teixeira, J.; Lam, R.; Pressel, K. G.
2014-12-01
Sub-grid scale (SGS) closures in current climate models are usually decomposed into several largely independent parameterization schemes for different cloud and convective processes, such as boundary layer turbulence, shallow convection, and deep convection. These separate parameterizations usually do not converge as the resolution is increased or as physical limits are taken. This makes it difficult to represent the interactions and smooth transition among different cloud and convective regimes. Here we present an eddy-diffusivity mass-flux (EDMF) closure that represents all sub-grid scale turbulent, convective, and cloud processes in a unified parameterization scheme. The buoyant updrafts and precipitative downdrafts are parameterized with a prognostic multiple-plume mass-flux (MF) scheme. The prognostic term for the mass flux is kept so that the life cycles of convective plumes are better represented. The interaction between updrafts and downdrafts are parameterized with the buoyancy-sorting model. The turbulent mixing outside plumes is represented by eddy diffusion, in which eddy diffusivity (ED) is determined from a turbulent kinetic energy (TKE) calculated from a TKE balance that couples the environment with updrafts and downdrafts. Similarly, tracer variances are decomposed consistently between updrafts, downdrafts and the environment. The closure is internally coupled with a probabilistic cloud scheme and a simple precipitation scheme. We have also developed a relatively simple two-stream radiative scheme that includes the longwave (LW) and shortwave (SW) effects of clouds, and the LW effect of water vapor. We have tested this closure in a single-column model for various regimes spanning stratocumulus, shallow cumulus, and deep convection. The model is also run towards statistical equilibrium with climatologically relevant large-scale forcings. These model tests are validated against large-eddy simulation (LES) with the same forcings. The comparison of results verifies the capacity of this closure to realistically represent different cloud and convective processes. Implementation of the closure in an idealized GCM allows us to study cloud feedbacks to climate change and to study the interactions between clouds, convections, and the large-scale circulation.
Pressure fluctuation caused by moderate acceleration
NASA Astrophysics Data System (ADS)
Tagawa, Yoshiyuki; Kurihara, Chihiro; Kiyama, Akihito
2017-11-01
Pressure fluctuation caused by acceleration of a liquid column is observed in various important technologies, e.g. water-hammer in a pipeline. The magnitude of fluctuation can be estimated by two different approaches: When the duration time of acceleration is much shorter than the propagation time for a pressure wave to travel the length of the liquid column, e.g. sudden valve closure for a long pipe, Joukowsky equation is applied. In contrast, if the acceleration duration is much longer, the liquid is modeled as a rigid column, ignoring compressibility of the fluid. However, many of practical cases exist between these two extremes. In this study we propose a model describing pressure fluctuation when the duration of acceleration is in the same order of the propagation time for a pressure wave, i.e. under moderate acceleration. The novel model considers both temporal and spatial evolutions of pressure propagation as well as gradual pressure rise during the acceleration. We conduct experiments in which we impose acceleration to a liquid with varying the length of the liquid column, acceleration duration, and properties of liquids. The ratio between the acceleration duration and the propagation time is in the range of 0.02 - 2. The model agrees well with measurement results. JSPS KAKENHI Grant Numbers 26709007 and 17H01246.
Experimental Verification of Steel Pipe Collapse under Vacuum Pressure Conditions
NASA Astrophysics Data System (ADS)
Autrique, R.; Rodal, E.
2016-11-01
Steel pipes are used widely in hydroelectric systems and in pumping systems. Both systems are subject to hydraulic transient effects caused by changes in boundary conditions, such as sudden valve closures, pump failures, or accidents. Water column separation, and its associated vaporization pressure inside the pipe, can cause the collapse of thin walled steel pipes subject to atmospheric pressure, as happened during the well known Oigawa Power Plant accident in Japan, in 1950. The conditions under which thin walled pipes subject to external pressure can collapse have been studied mathematically since the second half of the XIX century, with classical authors Southwell and Von Mises obtaining definitive equations for long and short pipes in the second decade of the XX century, in which the fundamental variables are the diameter to thickness ratio D/t and the length to diameter ratio L/D. In this paper, the predicted critical D/t ratio for steel pipe collapse is verified experimentally, in a physical model able to reproduce hydraulic transients, generating vacuum pressures through rapid upstream valve closures.
NASA Astrophysics Data System (ADS)
Wang, P.; Knap, W. H.; Kuipers Munneke, P.; Stammes, P.
2009-04-01
During the last two decades, several attempts have been made to achieve agreement between clear-sky shortwave broadband irradiance models and surface measurements of direct and diffuse irradiance. In general, models and measurements agreed well for the direct component but closing the gap for diffuse irradiances remained problematic. The number of studies reporting a satisfactory degree of closure for both direct and diffuse irradiance is still limited, which motivated us to perform the study presented here. In this paper a clear-sky shortwave closure analysis is presented for the Baseline Surface Radiation Network (BSRN) site of Cabauw, the Netherlands (51.97 °N, 4.93 °E). The analysis is based on an exceptional period of fine weather in the first half of May 2008 during the Intensive Measurement Period At the Cabauw Tower (IMPACT), an activity of the European Integrated project on Aerosol Cloud Climate and Air Quality Interactions (EUCAARI). Although IMPACT produced a wealth of data, it was decided to conduct the closure analysis using routine measurements only, provided by BSRN and the Aerosol Robotic Network (AERONET), completed with radiosonde obervations. The rationale for this pragmatic approach is the possibility of applying the method presented here to other periods and (BSRN) sites, where routine measurements are readily available, without having to deal with the investments and restrictions of an intensive observation period. The analysis is based on a selection of 72 comparisons on 6 days between BSRN measurements and Doubling Adding KNMI (DAK) model simulations of direct, diffuse, and global irradiance. The data span a wide range of aerosol properties, water vapour columns, and solar zenith angles. The model input consisted of operational Aerosol Robotic Network (AERONET) aerosol products and radiosonde data. On the basis of these data excellent closure was obtained: the mean differences between model and measurements are 2 W/m2 (+0.2%) for direct irradiance, 1 W/m2 (+0.8%) for diffuse irradiance, and 2 W/m2 (+0.3%) for global irradiance.
NASA Astrophysics Data System (ADS)
Dabney, P.; Harding, D. J.; Valett, S. R.; Yu, A. W.; Feliciano, E. A.; Neuenschwander, A. L.; Pitts, K.
2015-12-01
Determining the presence, persistence, optical properties and variation in height and slope of surface water beneath the dense canopies of flooded forests and mangrove stands could contribute to studies of the acquisition of water and nutrients by plant roots. NASA's airborne Slope Imaging Multi-polarization Photon-counting Lidar (SIMPL) provides unique capabilities that can identify below-canopy surface water, measure its height with respect to vegetation constituents with sub-decimeter precision and quantify its slope. It also provides information on canopy structure and closure, the water column extinction profile as a proxy for turbidity and water depth, with the penetration depth constrained by turbidity. It achieves this by using four laser beams operating at two wavelengths with measurements of water surface elevation at 1064 nm (near infrared) and water column properties at 532 nm (green), analogous to a bathymetric lidar. Importantly the instrument adds a polarimetry function, like some atmospheric lidars, which measures the amount of depolarization determined by the degree to which the plane-parallel transmitted laser pulse energy is converted to the perpendicular state. The degree of depolarization is sensitive to the number of photon multiple-scattering events. For the water surface, which is specular consisting only of single-scattering events, the near-infrared received signal retains the parallel polarization state. Absence of the perpendicular signal uniquely identifies surface water. Penetration of green light and the depth profile of photons converted to the perpendicular state compared to those in the parallel state is a measure of water-column multiple scattering, providing a relative measure of turbidity. The amount of photons reflected from the canopy versus the water provides a wavelength-dependent measure of canopy closure. By rapidly firing laser pulses (11,400 pulses per second) with a narrow width (1 nsec) and detecting single photons with 8 cm ranging precision, the surface altimetry data is acquired with very high spatial and vertical resolution. Examples of these capabilities will be shown using data collected in 2011 along and across the flow axis of the Florida Everglades Shark River Slough, targeting the slough's Long Term Ecology Research (LTER) field sites.
NASA Astrophysics Data System (ADS)
PéRez-Asensio, J. N.; Aguirre, J.; Schmiedl, G.; Civis, J.
2012-09-01
Messinian foraminiferal stable oxygen and carbon isotopes of the Montemayor-1 core (Guadalquivir Basin, SW Spain) have been investigated. This record is exceptional to study the Mediterranean Outflow Water (MOW) impact on the Atlantic meridional overturning circulation (AMOC) and global climate during the Messinian because the core is near the Guadalhorce Corridor, the last Betic gateway to be closed during the early Messinian. Our results allow dating accurately its closure at 6.18 Ma. Constant benthicδ18O values, high difference between benthic and planktonic δ18O, and low sedimentation rates before 6.18 Ma indicate the presence of a two-layer water column, with bottom winnowing due to an enhanced Mediterranean outflow current. The enhanced contribution of dense MOW to the North Atlantic Ocean likely fostered the formation of North Atlantic Deep Water (NADW). After 6.18 Ma, benthicδ18O values parallel that of the global glacioeustatic curve, the difference between benthic and planktonic δ18O is low, and sedimentation rates considerably increased. This indicates a good vertical mixing of the water column, interruption of the MOW, and a dominant glacioeustatic control on the isotopic signatures. According to the role of MOW in the modern Atlantic thermohaline circulation, the reduction of the MOW after the closure of the Guadalhorce Corridor might have resulted in a decreased NADW formation rate between 6.0 and 5.5 Ma weakening the AMOC and promoting northern hemisphere cooling. After the Gibraltar Strait opening, the restoration of the MOW and related salt export from the Mediterranean could have promoted an enhanced NADW formation.
1982-10-01
centerline by stanchions. A concrete beam is provided at the ship centerline to transfer unbalanced stanchion loads longitudinally along the shell . The 01...Place Cast-in-Place Concrete Connections -- Connections betw. an precast shell elements are made using cast-in-place concrete closure pours. See Figure...buckling using the column provi sions of the ACI code. For shells , the critical radius to thickness ratio is about 200 for cylindrical shells loaded in
NASA Astrophysics Data System (ADS)
Ackerman, A. S.; Kelley, M.; Cheng, Y.; Fridlind, A. M.; Del Genio, A. D.; Bauer, S.
2017-12-01
Reduction in cloud-water sedimentation induced by increasing droplet concentrations has been shown in large-eddy simulations (LES) and direct numerical simulation (DNS) to enhance boundary-layer entrainment, thereby reducing cloud liquid water path and offsetting the Twomey effect when the overlying air is sufficiently dry, which is typical. Among recent upgrades to ModelE3, the latest version of the NASA Goddard Institute for Space Studies (GISS) general circulation model (GCM), are a two-moment stratiform cloud microphysics treatment with prognostic precipitation and a moist turbulence scheme that includes an option in its entrainment closure of a simple parameterization for the effect of cloud-water sedimentation. Single column model (SCM) simulations are compared to LES results for a stratocumulus case study and show that invoking the sedimentation-entrainment parameterization option indeed reduces the dependence of cloud liquid water path on increasing aerosol concentrations. Impacts of variations of the SCM configuration and the sedimentation-entrainment parameterization will be explored. Its impact on global aerosol indirect forcing in the framework of idealized atmospheric GCM simulations will also be assessed.
Kuhlmann, O; Krauss, G J
1997-12-01
A sensitive and selective bioanalytical method for diclofenac using reversed-phase HPLC and fluorescence detection is described. Diclofenac was detected as its fluorescent derivative after on-line post-column photoderivatization. Irradiation with UV light of diclofenac in aqueous solutions leads to the sequential loss of both chlorine substituents and ring closure. The major product, carbazole-1-acetic acid, was detected by a fluorescence detector using an excitation wavelength of 286 nm and an emission wavelength of 360 nm. The self-made reactor was a crocheted ethylene and tetrafluoroethylene (ETFE, named TEFZEL) capillary, 20 m in length, wound directly around a 253.7 nm UV lamp. The capillary was crocheted in order to overcome peak widening. Chromatographic separation was achieved by using a Regis SPS 100 RP-8 column (5 microm; 150 mm x 4.6 mm i.d.) and a LiChrospher 100 RP-18 (5 microm) guard column from E. Merck. The detection limit was 1 ng ml(-1) at an injection volume of 20 microl. Daily relative standard deviations (RSD) were 5.5%, (73 ng diclofenac/ml, n = 9), and 5.1% (405 ng diclofenac/ml, n = 6), respectively. Chromatograms of human aqueous humor and human serum containing diclofenac, and figures showing the time dependent increase/decrease of the photoderivatization product, are shown.
NASA Astrophysics Data System (ADS)
Wagner, Thomas
2017-04-01
Measurements of the oxygen dimer O4 are often used in remote sensing applications to infer information on the atmospheric light path distribution. Such information is interesting in itself, but can also be used to retrieve properties of clouds and aerosols, e.g. from ground based Multi-AXis-Differential Optical Absorption Spectroscopy (MAX-DOAS) observations. In recent years, a scaling factor (between about 0.7 and 1) was applied by several groups to the retrieved O4 slant column densities in order to obtain meaningful aerosol profiles from MAX-DOAS observations. However, other groups did not report the need for such a scaling factor. Up to now, this discrepancy is neither understood nor resolved. Here we compare measured and modelled O4 slant column densities for two days during the MADCAT campaign (http://joseba.mpch-mainz.mpg.de/mad_cat.htm). Clouds were mostly absent during both days, and the aerosol profiles are constrained by simultaneous sun photometer and ceilometer measurements. One important difference between both days is the amount of aerosol in the lowest atmospheric layer. Our comparison study addresses several important steps of the O4 data analysis, such as the spectral retrieval and the radiative transfer simulations. We also investigate the effects of temperature and pressure variations on the calculation of the O4 vertical column density. Preliminary results are are not conclusive but indicate that a scaling factor is needed to bring measurements and simulations into agreement at least for one of the two selected days.
Modal and thermal analysis of Les Arches unstable rock column (Vercors massif, French Alps)
NASA Astrophysics Data System (ADS)
Bottelin, P.; Lévy, C.; Baillet, L.; Jongmans, D.; Guéguen, P.
2013-08-01
A potentially unstable limestone column (˜1000 m3, Vercors, French Alps) delineated by an open rear fracture was continuously instrumented with two three-component seismic sensors from mid-May 2009 to mid-October 2011. Spectral analysis of seismic noise allowed several resonance frequencies to be determined, ranging from 6 to 21 Hz. The frequency domain decomposition (FDD) technique was applied to the ambient vibrations recorded on the top of the rock column. Three vibration modes were identified at 6, 7.5 and 9 Hz, describing the upper part of corresponding modal shapes. Finite element numerical modelling of the column dynamic response confirmed that the first two modes are bending modes perpendicular and parallel to the fracture, respectively, while the third one corresponds to torsion. Seismic noise monitoring also pointed out that resonance frequencies fluctuate with time, under thermomechanical control. For seasonal cycles, changes in frequency are due to the variations of the bulk elastic properties with temperature. At daily scale, increase in fundamental frequency with temperature has been interpreted as resulting from the rock expansion inducing a closure of the rear fracture rock bridges, hence stiffening the contact between the column and the rock mass. Conversely, the rock contraction induces a fracture opening and a decrease in resonance frequency. In winter, when the temperature drops below 0 °C, a dramatic increase in fundamental frequency is observed from 6 Hz to more than 25 Hz, resulting from ice formation in the fracture. During spring, the resonance frequency gradually diminishes with ice melting to reach the value measured before winter.
NASA Technical Reports Server (NTRS)
Schmid, B.; Hegg, A.; Wang, J.; Bates, D.; Redemann, J.; Russells, P. B.; Livingston, J. M.; Jonsson, H. H.; Welton, E. J.; Seinfield, J. H.
2003-01-01
We assess the consistency (closure) between solar beam attenuation by aerosols and water vapor measured by airborne sunphotometry and derived from airborne in-situ, and ship-based lidar measurements during the April 2001 Asian Pacific Regional Aerosol Characterization Experiment (ACE-Asia). The airborne data presented here were obtained aboard the Twin Otter aircraft. Comparing aerosol extinction o(550 nm) from four different techniques shows good agreement for the vertical distribution of aerosol layers. However, the level of agreement in absolute magnitude of the derived aerosol extinction varied among the aerosol layers sampled. The sigma(550 nm) computed from airborne in-situ size distribution and composition measurements shows good agreement with airborne sunphotometry in the marine boundary layer but is considerably lower in layers dominated by dust if the particles are assumed to be spherical. The sigma(550 nm) from airborne in-situ scattering and absorption measurements are about approx. 13% lower than those obtained from airborne sunphotometry during 14 vertical profiles. Combining lidar and the airborne sunphotometer measurements reveals the prevalence of dust layers at altitudes up to 10 km with layer aerosol optical depth (from 3.5 to 10 km altitude) of approx. 0.1 to 0.2 (500 nm) and extinction-to-backscatter ratios of 59-71 sr (523 nm). The airborne sunphotometer aboard the Twin Otter reveals a relatively dry atmosphere during ACE- Asia with all water vapor columns less than 1.5 cm and water vapor densities w less than 12 g/cu m. Comparing layer water vapor amounts and w from the airborne sunphotometer to the same quantities measured with aircraft in-situ sensors leads to a high correlation (r(sup 3)=0.96) but the sunphotometer tends to underestimate w by 7%.
NASA Astrophysics Data System (ADS)
Reichert, Andreas; Sussmann, Ralf; Rettinger, Markus
2014-05-01
Uncertainties in the knowledge of atmospheric radiative processes are among the main limiting factors for the accuracy of current climate models. Being the primary greenhouse gas in the Earth's atmosphere, water vapor is of crucial importance in atmospheric radiative transfer. However, water vapor absorption processes, especially the contribution attributed to the water vapor continuum, are currently not sufficiently well quantified. The aim of this study is therefore to obtain a more exact characterization of the water vapor radiative processes throughout the IR by means of a so-called radiative closure study at the Zugspitze/Schneefernerhaus observatory and thereby validate the radiative transfer codes used in current climate models. For that purpose, spectral radiance is measured at the Zugspitze summit observatory using an AERI-ER thermal emission radiometer (covering the far- and mid-infrared) and a solar absorption FTIR spectrometer (covering the near-infrared), respectively. These measurements are then compared to synthetic radiance spectra computed by means of the Line-By-Line Radiative Transfer Model (LBLRTM, Clough et al., 2005), a high resolution model widely used in the atmospheric science community. This line-by-line code provides the foundation of RRTM, a rapid radiation code (Mlawer et al., 1997) used in various weather forecast models or general circulation models like ECHAM. To be able to quantify errors in the description of water vapor radiative processes from spectral residuals, i.e. difference spectra between measured and calculated radiance, the atmospheric state used as an input to LBLRTM has to be constrained precisely. This input comprises water vapor columns, water vapor profiles, and temperature profiles measured by an LHATPRO microwave radiometer along with total column information on further trace gases (e.g. CO2 and O3) measured by the solar FTIR. We will present the setup of the Zugspitze radiative closure experiment. Due to its high-altitude location and the available permanent instrumentation, the Zugspitze observatory meets the necessary requirements to determine highly accurate water vapor continuum absorption parameters in the far- and mid-infrared spectral range from a more extensive set of closure measurements compared to previous campaign-based studies. Furthermore, we will present a novel radiometric calibration strategy for the solar FTIR spectral radiance measurements based on a combination of the Langley method and measurements of a high-temperature blackbody source that allows for the determination of continuum absorption parameters in the near-infrared spectral region, where previously no precise measurements under atmospheric conditions were available. This improved quantification of water vapor continuum absorption parameters allows us to further validate the current standard continuum model MT_CKD (Mlawer et al., 2012). Acknowledgements: Funding by KIT/IMK-IFU, the State Government of Bavaria as well as by the Deutsche Bundesstiftung Umwelt (DBU) is gratefully acknowledged. References: Clough, S. A., Shephard, M. W., Mlawer, E. J., Delamere, J. S., Iacono, M. J., Cady-Pereira, K., Boukabara, S., and Brown, P. D: Atmospheric radiative transfer modeling: a summary of the AER codes, Short Communication, J. Quant. Spectrosc. Radiat. Transfer, 91, 233-244, 2005. Mlawer, E. J., Taubman, J., Brown, P.D., Iacono, M.J, and Clough, S.A.: RRTM, a validated correlated-k model for the longwave. J. Geophys. Res., 102, 16,663-16,682, 1997. Mlawer, E. J., Payne V. H., Moncet, J., Delamere, J. S., Alvarado, M. J. and Tobin, D.C.: Development and recent evaluation of the MT_CKD model of continuum absorption, Phil. Trans. R. Soc. A, 370, 2520-2556, 2012.
On Averaging Timescales for the Surface Energy Budget Closure Problem
NASA Astrophysics Data System (ADS)
Grachev, A. A.; Fairall, C. W.; Persson, O. P. G.; Uttal, T.; Blomquist, B.; McCaffrey, K.
2017-12-01
An accurate determination of the surface energy budget (SEB) and all SEB components at the air-surface interface is of obvious relevance for the numerical modelling of the coupled atmosphere-land/ocean/snow system over different spatial and temporal scales, including climate modelling, weather forecasting, environmental impact studies, and many other applications. This study analyzes and discusses comprehensive measurements of the SEB and the surface energy fluxes (turbulent, radiative, and ground heat) made over different underlying surfaces based on the data collected during several field campaigns. Hourly-averaged, multiyear data sets collected at two terrestrial long-term research observatories located near the coast of the Arctic Ocean at Eureka (Canadian Archipelago) and Tiksi (East Siberia) and half-hourly averaged fluxes collected during a year-long field campaign (Wind Forecast Improvement Project 2, WFIP 2) at the Columbia River Gorge (Oregon) in areas of complex terrain. Our direct measurements of energy balance show that the sum of the turbulent sensible and latent heat fluxes systematically underestimate the available energy at half-hourly and hourly time scales by around 20-30% at these sites. This imbalance of the surface energy budget is comparable to other terrestrial sites. Surface energy balance closure is a formulation of the conservation of energy principle (the first law of thermodynamics). The lack of energy balance closure at hourly time scales is a fundamental and pervasive problem in micrometeorology and may be caused by inaccurate estimates of the energy storage terms in soils, air and biomass in the layer below the measurement height and above the heat flux plates. However, the residual energy imbalance is significantly reduced at daily and monthly timescales. Increasing the averaging time to daily scales substantially reduces the storage terms because energy locally entering the soil, air column, and vegetation in the morning is released in the afternoon and evening.
NASA Astrophysics Data System (ADS)
Elsayed Yousef, Ahmed; Ehsan, M. Azhar; Almazroui, Mansour; Assiri, Mazen E.; Al-Khalaf, Abdulrahman K.
2017-02-01
A new closure and a modified detrainment for the simplified Arakawa-Schubert (SAS) cumulus parameterization scheme are proposed. In the modified convective scheme which is named as King Abdulaziz University (KAU) scheme, the closure depends on both the buoyancy force and the environment mean relative humidity. A lateral entrainment rate varying with environment relative humidity is proposed and tends to suppress convection in a dry atmosphere. The detrainment rate also varies with environment relative humidity. The KAU scheme has been tested in a single column model (SCM) and implemented in a coupled global climate model (CGCM). Increased coupling between environment and clouds in the KAU scheme results in improved sensitivity of the depth and strength of convection to environmental humidity compared to the original SAS scheme. The new scheme improves precipitation simulation with better representations of moisture and temperature especially during suppressed convection periods. The KAU scheme implemented in the Seoul National University (SNU) CGCM shows improved precipitation over the tropics. The simulated precipitation pattern over the Arabian Peninsula and Northeast African region is also improved.
Kitsios, Georgios D; Dahabreh, Issa J; Abu Dabrh, Abd Moain; Thaler, David E; Kent, David M
2012-02-01
Patients discovered to have a patent foramen ovale in the setting of a cryptogenic stroke may be treated with percutaneous closure, antiplatelet therapy, or anticoagulants. A recent randomized trial (CLOSURE I) did not detect any benefit of closure over medical treatment alone; the optimal medical therapy is also unknown. We synthesized the available evidence on secondary stroke prevention in patients with patent foramen ovale and cryptogenic stroke. A MEDLINE search was performed for finding longitudinal studies investigating medical treatment or closure, meta-analysis of incidence rates (IR), and IR ratios of recurrent cerebrovascular events. Fifty-two single-arm studies and 7 comparative nonrandomized studies and the CLOSURE I trial were reviewed. The summary IR of recurrent stroke was 0.36 events (95% confidence interval [CI], 0.24-0.56) per 100 person-years with closure versus 2.53 events (95% CI, 1.91-3.35) per 100 person-years with medical therapy. In comparative observational studies, closure was superior to medical therapy (IR ratio=0.19; 95% CI, 0.07-0.54). The IR for the closure arm of the CLOSURE I trial was higher than the summary estimate from observational studies; there was no significant benefit of closure over medical treatment (P=0.002 comparing efficacy estimates between observational studies and the trial). Observational and randomized data (9 studies) comparing medical therapies were consistent and suggested that anticoagulants are superior to antiplatelets for preventing stroke recurrence (IR ratio=0.42; 95% CI, 0.18-0.98). Although further randomized trial data are needed to precisely determine the effects of closure on stroke recurrence, the results of CLOSURE I challenge the credibility of a substantial body of observational evidence strongly favoring mechanical closure over medical therapy.
Observations on early and delayed colostomy closure.
Tade, A O; Salami, B A; Ayoade, B A
2011-06-01
Traditional treatment of a variety of colorectal pathologies had included a diverting colostomy that was closed eight or more weeks later during a readmission. The aim of this retrospective study was to determine the outcomes of early colostomy closure and delayed colostomy closure in patients with temporary colostomies following traumatic and non-traumatic colorectal pathologies. In this study early colostomy closure was the closure of a colostomy within three weeks of its construction, while delayed colostomy closure referred to closure after 3 weeks. Complete records of the 37 adult patients who had temporary colostomy constructed and closed between Jan. 1997 December 2003 for various colorectal pathologies were studied. Fourteen patients had early colostomy closure while 23 had delayed closure. In the early colostomy closure group there were 10 men and 4 women. The mean age of the patients was 28yr with a range of 18-65yr. Colostomies were closed 9-18 days after initial colostomy construction. There was no mortality. Morbidity rate 28.6% (4 out of 14). There were two faecal fistulas (14.3%). Twenty-three patients had delayed colostomy closure 8 weeks to 18 months after initial colostomy construction. These were patients unfit for early surgery after initial colostomy construction because of carcinoma, significant weight loss, or sepsis. There was no mortality. Morbidity rate was 26.1%. There were 3 faecal fistulas (13.2%). Outcomes following early colostomy closure and delayed closure were comparable. Patients fit for surgery should have early closure whilst patients who may have compromised health should have delayed closure.
Impact of Vial Capping on Residual Seal Force and Container Closure Integrity.
Mathaes, Roman; Mahler, Hanns-Christian; Roggo, Yves; Ovadia, Robert; Lam, Philippe; Stauch, Oliver; Vogt, Martin; Roehl, Holger; Huwyler, Joerg; Mohl, Silke; Streubel, Alexander
2016-01-01
The vial capping process is a critical unit operation during drug product manufacturing, as it could possibly generate cosmetic defects or even affect container closure integrity. Yet there is significant variability in capping equipment and processes, and their relation to potential defects or container closure integrity has not been thoroughly studied. In this study we applied several methods-residual seal force tester, a self-developed system of a piezo force sensor measurement, and computed tomography-to characterize different container closure system combinations that had been sealed using different capping process parameter settings. Additionally, container closure integrity of these samples was measured using helium leakage (physical container closure integrity) and compared to characterization data. The different capping equipment settings lead to residual seal force values from 7 to 115 N. High residual seal force values were achieved with high capping pre-compression force and a short distance between the capping plate and plunge. The choice of container closure system influenced the obtained residual seal force values. The residual seal force tester and piezoelectric measurements showed similar trends. All vials passed physical container closure integrity testing, and no stopper rupture was seen with any of the settings applied, suggesting that container closure integrity was warranted for the studied container closure system with the chosen capping setting ranges. The vial capping process is a critical unit operation during drug product manufacturing, as it could possibly generate cosmetic defects or even affect container closure integrity. Yet there is significant variability in capping equipment and processes, and their relation to potential defects or container closure integrity has not been thoroughly studied. In this study we applied several methods-residual seal force tester, a self-developed system of a piezo force sensor measurement, and computed tomography-to characterize different container closure system combinations that had been sealed using different capping process parameter settings. The residual seal force tester can analyze a variety of different container closure systems independent of the capping equipment. An adequate and safe residual seal force range for each container closure system configuration can be established with the residual seal force tester and additional methods like computed tomography scans and leak testing. In the residual seal force range studied, the physical container closure integrity of the container closure system was warranted. © PDA, Inc. 2016.
NASA Technical Reports Server (NTRS)
Schmid, Beat; Collins, Donald R.; Gasso, Santiago; Oestroem, Elisabeth; Powell, Donna M.; Welton, Ellsworth J.; Durkee, Philip A.; Livingston, John M.; Russell, Philip B.; Flagan, Richard C.;
2000-01-01
We report on clear-sky column closure experiments (CLEARCOLUMN) performed in the Canary Islands during the second Aerosol Characterization Experiment (ACE-2) in June/July 1997. We present CLEARCOLUMN results obtained by combining airborne sunphotometer and in-situ (a differential mobility analyzer, three optical particle counters, three nephelometers, and one absorption photometer) measurements taken aboard the Pelican aircraft, space-borne NOAA/AVHRR data and ground-based lidars. A wide range of aerosol types was encountered throughout the ACE-2 area, including background Atlantic marine, European pollution-derived, and (although less frequently than expected) African mineral dust. During the two days discussed here, vertical profiles flown in cloud free air masses revealed three distinctly different layers: a marine boundary layer (MBL) with varying pollution levels, an elevated dust layer, and a very clean layer between the MBL and the dust layer. Based on size-resolved composition information we have established an aerosol model that allows us to compute optical properties of the ambient aerosol using the optical particle counter results. In the dust, the agreement in layer AOD (lambda=380-1060 nm) is 3-8%. In the MBL there is a tendency for the in-situ results to be slightly lower than the sunphotometer measurements (10-17% at lambda=525 nm), but these differences are within the combined error bars of the measurements and computations. Aerosol size-distribudon closure based on in-situ size distributions and inverted sunphotometer extinction spectra has been achieved in the MBL (total surface area and volume agree within 0.2, and 7%, respectively) but not in the dust layer. The fact that the three nephelometers operated at three different relative humidities (RH) allowed to parameterize hygroscopic growth and to therefore estimate optical properties at ambient RH. The parameters derived for different aerosol types are themselves useful for the aerosol modeling community. The fact that the nephelometers and the absorption photometer sampled the aerosol through a cyclone make those measurements less useful for thee closure study carried out here. Large corrections (especially in the dust) had to be applied. Therefore, it is not surprising that closure with the sunphotometer was not always achieved. Agreement within 0.02 in AOD was achieved in the dust layer when the airorne sunphotometer extinction or AOD was compared to ground-based lidar measurements. We found that the presence of the elevated dust layers removes the good agreement between satellite and sunphotometer AOD usually found in the absence of the dust layer. We still compare the scattering phase functions used in the satellite retrieval with those obtained from the aerosol or the sunphotometer measurements.
NASA Astrophysics Data System (ADS)
Houben, H.; Bergstrom, R. W.; Russell, P. B.; Pilewskie, P.
2006-12-01
Characterization of atmospheric aerosols and their climatic effects frequently requires more information than can be gathered by a single instrument. Considerable effort must be devoted to assembling a suite of complementary instruments to make the required measurements and to the production of computational tools that can fuse the data into a coherent description of the aerosols. The twin turboprop Sky Research Jetstream-31 (J-31) has participated in a number of recent field campaigns (Intex A/ICARTT, Intex B/Milagro) with goals that include column closure studies of atmospheric radiation and satellite validation. Among the instruments on board were the 14-channel NASA Ames Airborne Tracking Sunphotometer (AATS-14, which measures the transmission of the solar beam in 14 narrow spectral channels from 354 nm to 2139 nm with bandwidths between 2 and 6 nm for most channels) and the Solar Spectral Flux Radiometer (SSFR, a moderate resolution flux [irradiance] spectrometer with a hemispheric field of view which makes simultaneous zenith and nadir measurements in the wavelength range from 300 nm to 2200 nm with spectral resolution 8--12 nm). To retrieve the data we have developed a new adjointed radiative transfer model which simultaneously predicts the direct solar beam, upwelling and downwelling fluxes at the J-31 level, and satellite radiances. The code is based on an adding-doubling formulation, with an arbitrary number of streams and azimuths. The matrix form of the model allows for straightforward (though complicated) linearized and adjoint versions. We are thus able to use data assimilation techniques to determine best-fit aerosol properties above and below the J-31 (and ocean surface albedo), based on approximately 25 independent measurements from the aircraft alone. The presence of both flux and extinction data allow the ready identification of absorbing and scattering aerosols. When column closure spirals are flown, or surface or satellite data are available, a more detailed description of the aerosol and its vertical distribution can be obtained. We believe the J-31 platform and the new radiation code constitute an important facility for the validation of satellite aerosol observations.
Sun, Xu; Zhu, Ze-Zhang; Chen, Xi; Liu, Zhen; Wang, Bin; Qiu, Yong
2016-08-01
This paper presents a highly challenging technique involving posterior double vertebral column resections (VCRs) and satellite rods placement. This was a young adult case with severe angular thoracolumbar kyphosis of 101 degrees, secondary to anterior segmentation failure from T11 to L1 . There were hemivertebrae at T11 and T12 , and a wedged vertebra at L1 . He received double VCRs at T12 and T11 and instrumented fusion from T6 to L4 via a posterior only approach. Autologous grafts and a cage were placed between the bony surfaces of the osteotomy gap. Once closure of osteotomy was achieved, bilateral permanent CoCr rods were placed with addition of satellite rods. Postoperative X-ray demonstrated marked correction of kyphosis. On the 10(th) days after surgery, the patient was able to walk without assistance. In conclusion, double VCRs are effective to correct severe angular kyphosis, and addition of satellite rods may be imperative to enhance instrumentation strength and thus prevent correction loss. © 2016 Chinese Orthopaedic Association and John Wiley & Sons Australia, Ltd.
Lace Up for Healthy Feet: The Impact of Shoe Closure on Plantar Stress Response.
Rahemi, Hadi; Armstrong, David G; Enriquez, Ana; Owl, Joshua; Talal, Talal K; Najafi, Bijan
2017-07-01
This study examined the impact of shoe closure on plantar thermal stress response (TSR), which is known to be a surrogate of shear stress and skin perfusion. It is aimed to explore potential impact of shoe closure on increasing risk factors associated with plantar ulcers in people with diabetic peripheral neuropathy (DPN). Fifteen eligible subjects were enrolled. The left foot was used as a reference and fitted to a self-adjusted and habitual lace-tightening method by each subject. The right foot was used as a test closure and fitted into three lace closure conditions: loose, tight, and preset optimal closure (reel clutch, BOA technology). Thermal images were taken after 5 minutes of acclimatization (pre-trial) and immediately after 200 walking steps in each shoe closure condition (post-trial). TSR was calculated from the thermal images. TSR was significantly higher in the test closure with loose (70.24%, P = .000) and tight (66.85%, P = .007) and lower (-206.53%, P = .000) in the preset optimal closure when compared to the reference closure. Only lace closure conditions affected TSR with no significant impact from age, BMI, and gender in our sample in a multivariable regression model. The results from this study suggest that shoelace closure technique can have a profound effect on TSR. It therefore stands to reason that optimal lace closure may have an impact in reducing risk of plantar ulcers in people with DPN. Interestingly, results revealed that even a self-adjusted lace closure may not be necessarily optimal and a preset closure setting like reel clutch might ultimately be recommended to minimize risk. Further study is warranted to confirm or refute these interesting results.
Seven-year follow-up of percutaneous closure of patent foramen ovale.
Mirzada, Naqibullah; Ladenvall, Per; Hansson, Per-Olof; Johansson, Magnus Carl; Furenäs, Eva; Eriksson, Peter; Dellborg, Mikael
2013-12-01
Observational studies favor percutaneous closure of patent foramen ovale (PFO) over medical treatment to reduce recurrent stroke while randomized trials fail to demonstrate significant superiority of percutaneous PFO closure. Few long-term studies are available post PFO closure. This study reports long-term clinical outcomes after percutaneous PFO closure. Between 1997 and 2006, 86 consecutive eligible patients with cerebrovascular events, presumably related to PFO, underwent percutaneous PFO closure. All 86 patients were invited to a long-term follow-up, which was carried out during 2011 and 2012. Percutaneous PFO closure was successfully performed in 85 of 86 patients. The follow-up rate was 100%. No cardiovascular or cerebrovascular deaths occurred. Two patients (both women) died from lung cancer during follow-up. Follow-up visits were conducted for 64 patients and the remaining 20 patients were followed up by phone. The mean follow-up time was 7.3 years (5 to 12.4 years). Mean age at PFO closure was 49 years. One patient had a minor stroke one month after PFO closure and a transient ischemic attack (TIA) two years afterwards. One other patient suffered from a TIA six years after closure. No long-term device-related complications were observed. Percutaneous PFO closure was associated with very low risk of recurrent stroke and is suitable in most patients. We observed no mortality and no long-term device-related complications related to PFO closure, indicating that percutaneous PFO closure is a safe and efficient treatment even in the long term.
A prospective study of two methods of closing surgical scalp wounds.
Adeolu, A A; Olabanji, J K; Komolafe, E O; Ademuyiwa, A O; Awe, A O; Oladele, A O
2012-02-01
Scalp wounds are commonly closed in two layers, although single layer closure is feasible. This study prospectively compared the two methods of closing scalp wounds. Patients with non-traumatic scalp wounds were allocated to either the single layer closure group or the multilayer closure group. We obtained relevant data from the patients. The primary outcome measures were wound edge related complications, rate of suturing and cost of sutures used for suturing. Thirty-one wounds were in the single layer closure group and 30 were in the multilayer closure group. Age range was 1-80 years. The most common indication for making a scalp incision was subdural hematoma, representing 27.8% of all the indications. The most common surgery was burr hole drainage of subdural hematoma. Polyglactin acid suture was used for the inner layer and polyamide -00- for the final layer in the multilayer closure group. Only the latter suture was used for the single layer closure method. Total cost of suturing per wound in the single layer closure group was N= 100 (0.70USD) and N= 800 (5.30USD) in the multilayer group. The mean rate of closure was 0.39 ± 1.89 mm/sec for single layer closure and 0.23 ± 0.89 mm/sec in multilayer closure. The difference was statistically significant. Wound edge related complication rate was 19.35% in the single layer closure group and 16.67% in the multilayer closure method group. The difference was not statistically significant (z: 0.00, p value: 1.000; Pearson chi-squared (DF = 1)= 0.0075, p = 0.0785). The study shows that closing the scalp in one layer is much faster and more cost effective compared to the multilayer closure method. We did not observe significant difference in the complication rates in the two methods of closure. Long-term outcome, especially cosmetic outcome, remains to be determined in this preliminary study.
Primary closure versus delayed closure for non bite traumatic wounds within 24 hours post injury.
Eliya-Masamba, Martha C; Banda, Grace W
2013-10-22
Acute traumatic wounds are one of the common reasons why people present to the emergency department. Primary closure has traditionally been reserved for traumatic wounds presenting within six hours of injury and considered 'clean' by the attending surgeon, with the rest undergoing delayed primary closure as a means of controlling wound infection. Primary closure has the potential benefit of rapid wound healing but poses the potential threat of increased wound infection. There is currently no evidence to guide clinical decision-making on the best timing for closure of traumatic wounds. To determine the effect on time to healing of primary closure versus delayed closure for non bite traumatic wounds presenting within 24 hours post injury. To explore the adverse effects of primary closure compared with delayed closure for non bite traumatic wounds presenting within 24 hours post injury. In May 2013, for this first update we searched the Cochrane Wounds Group Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library); Ovid MEDLINE; Ovid MEDLINE (In-Process & Other Non-Indexed Citations); Ovid EMBASE; and EBSCO CINAHL. There were no restrictions with respect to language, date of publication or study setting. Randomised controlled trials comparing primary closure with delayed closure of non bite traumatic wounds. Two review authors independently evaluated the results of the searches against the inclusion criteria. No studies met the inclusion criteria for this review. Since no studies met the inclusion criteria, neither a meta-analysis nor a narrative description of studies was possible. There is currently no systematic evidence to guide clinical decision-making regarding the timing for closure of traumatic wounds. There is a need for robust research to investigate the effect of primary closure compared with delayed closure for non bite traumatic wounds presenting within 24 hours of injury.
Zakkar, Mustafa; Kanagasabay, Robin; Hunt, Ian
2014-04-01
A best evidence topic in cardiothoracic surgery was written according to a structured protocol. The question addressed was whether manual closure of the bronchial stump is safer with lower failure rates than mechanical closure using a stapling device following anatomical lung resection. One hundred and twenty-nine papers were identified using the search below. Eight papers presented the best evidence to answer the clinical question as they included sufficient number of patients to reach conclusions regarding the issues of interest for this review. Complications, complication rates and operation time were included in the assessment. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of the papers are tabulated. When looking at manual vs mechanical staples, it was noted that stapler failure can occur in around 4% of cases. The rate of bronchopleural fistula (BPF) development varied more in patients who underwent manual closure (1.5-12.5%) than in patients who underwent mechanical closure (1-5.7%). Although most of the studies reviewed showed no statistical differences between manual and mechanical closure in terms of BPF development, one study, however, showed that manual closure was significantly associated with lower numbers of postoperative BPF, while another study showed that mechanical closure is significantly associated with lower incidence of BPF. When looking at the role of the learning curve and training opportunities, it seems that the surgeon's inexperience when using mechanical staples can contribute to BPF development. A surgeon's experience can play a major role in the prevention of BPF development in patients having manual closure. Manual closure can provide a cheap and reliable technique when compared with costs incurred from using staplers, it is applicable in all situations and can be taught to surgeons in training with an acceptable risk. However, there is a lack of evidence to suggest that manual closure is better than mechanical stapler closure following anatomical lung resection.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Prescott, M.P.
1990-09-01
Significant new gas reserves have recently been discovered in the Marginulina texana sands along the Oligocene trend at the Maurice field. Detailed subsurface maps and seismic data are presented to exhibit the extent and nature of this local buried structure and to demonstrate future opportunities along the Oligocene trend. Since discovery in 1988, the MARG. TEX. RC has extended the Maurice field one-half mile south and has encountered over 170 ft of Marginulina texana pay Estimated reserves are in the order of 160 BCFG with limits of the reservoir still unknown. This reserve addition would increase the estimated ultimate ofmore » the Maurice field by over 70% from 220 BCFG to 380 BCFG. Cross sections across the field depict the new reservoir trap as a buried upthrown fault closure with an anticipated gas column of 700 ft. Interpretation of the origin of this local structure is that of a buried rotated fault block on an overall larger depositional structure. Detailed subsurface maps at the Marginulina texana and the overlying Miogypsinoides level are presented. These maps indicate that one common fault block is productive from two different levels. The deeper Marginulina texana sands are trapped on north dip upthrown to a southern boundary fault, Fault B. The overlying Miogypsinoides sands are trapped on south dip downthrown to a northern boundary fault, Fault A. The northern boundary fault, Fault A, was the Marginulina texana expansion fault and rotated that downthrown section to north dip. Because of the difference in dip between the two levels, the apex of the deeper Marginulina texana fault closure is juxtaposed by one mile south relative to the overlying Miogypsinoides fault closure. Analysis indicates that important structural growth occur-red during Marginulina texana deposition with a local unconformity covering the apex of the upthrown fault closure. State-of-the-art reconnaissance seismic data clearly exhibit this buried rotated fault block.« less
Effects of hydrated lime on radionuclides stabilization of Hanford tank residual waste.
Wang, Guohui; Um, Wooyong; Cantrell, Kirk J; Snyder, Michelle M V; Bowden, Mark E; Triplett, Mark B; Buck, Edgar C
2017-10-01
Chemical stabilization of tank residual waste is part of a Hanford Site tank closure strategy to reduce overall risk levels to human health and the environment. In this study, a set of column leaching experiments using tank C-104 residual waste were conducted to evaluate the leachability of uranium (U) and technetium (Tc) where grout and hydrated lime were applied as chemical stabilizing agents. The experiments were designed to simulate future scenarios where meteoric water infiltrates through the vadose zones into the interior of the tank filled with layers of grout or hydrated lime, and then contacts the residual waste. Effluent concentrations of U and Tc were monitored and compared among three different packing columns (waste only, waste + grout, and waste + grout + hydrated lime). Geochemical modeling of the effluent compositions was conducted to determine saturation indices of uranium solid phases that could control the solubility of uranium. The results indicate that addition of hydrated lime strongly stabilized the uranium through transforming uranium to a highly insoluble calcium uranate (CaUO 4 ) or similar phase, whereas no significant stabilization effect of grout or hydrated lime was observed on Tc leachability. The result implies that hydrated lime could be a great candidate for stabilizing Hanford tank residual wastes where uranium is one of the main concerns. Published by Elsevier Ltd.
The Effect of Rural Hospital Closures on Community Economic Health
Holmes, George M; Slifkin, Rebecca T; Randolph, Randy K; Poley, Stephanie
2006-01-01
Objective To examine the effect of rural hospital closures on the local economy. Data Sources U.S. Census Bureau, OSCAR, Medicare Cost Reports, and surveys of individuals knowledgeable about local hospital closures. Study Design Economic data at the county level for 1990–2000 were combined with information on hospital closures. The study sample was restricted to rural counties experiencing a closure during the sample period. Longitudinal regression methods were used to estimate the effect of hospital closure on per-capita income, unemployment rate, and other community economic measures. Models included both leading and lagged closure terms allowing a preclosure economic downturn as well as time for the closure to be fully realized by the community. Data Collection Information on closures was collected by contacting every state hospital association, reconciling information gathered with that contained in the American Hospital Association file and OIG reports. Principal Findings Results indicate that the closure of the sole hospital in the community reduces per-capita income by $703 (p<0.05) or 4 percent (p<0.05) and increases the unemployment rate by 1.6 percentage points (p<0.01). Closures in communities with alternative sources of hospital care had no long-term economic impact, although income decreased for 2 years following the closure. Conclusions The local economic effects of a hospital closure should be considered when regulations that affect hospitals' financial well-being are designed or changed. PMID:16584460
Jackson, Charlotte; Mangtani, Punam; Hawker, Jeremy; Olowokure, Babatunde; Vynnycky, Emilia
2014-01-01
School closure is a potential intervention during an influenza pandemic and has been investigated in many modelling studies. To systematically review the effects of school closure on influenza outbreaks as predicted by simulation studies. We searched Medline and Embase for relevant modelling studies published by the end of October 2012, and handsearched key journals. We summarised the predicted effects of school closure on the peak and cumulative attack rates and the duration of the epidemic. We investigated how these predictions depended on the basic reproduction number, the timing and duration of closure and the assumed effects of school closures on contact patterns. School closures were usually predicted to be most effective if they caused large reductions in contact, if transmissibility was low (e.g. a basic reproduction number <2), and if attack rates were higher in children than in adults. The cumulative attack rate was expected to change less than the peak, but quantitative predictions varied (e.g. reductions in the peak were frequently 20-60% but some studies predicted >90% reductions or even increases under certain assumptions). This partly reflected differences in model assumptions, such as those regarding population contact patterns. Simulation studies suggest that school closure can be a useful control measure during an influenza pandemic, particularly for reducing peak demand on health services. However, it is difficult to accurately quantify the likely benefits. Further studies of the effects of reactive school closures on contact patterns are needed to improve the accuracy of model predictions.
Zakkar, Mustafa; Kanagasabay, Robin; Hunt, Ian
2014-01-01
A best evidence topic in cardiothoracic surgery was written according to a structured protocol. The question addressed was whether manual closure of the bronchial stump is safer with lower failure rates than mechanical closure using a stapling device following anatomical lung resection. One hundred and twenty-nine papers were identified using the search below. Eight papers presented the best evidence to answer the clinical question as they included sufficient number of patients to reach conclusions regarding the issues of interest for this review. Complications, complication rates and operation time were included in the assessment. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of the papers are tabulated. When looking at manual vs mechanical staples, it was noted that stapler failure can occur in around 4% of cases. The rate of bronchopleural fistula (BPF) development varied more in patients who underwent manual closure (1.5–12.5%) than in patients who underwent mechanical closure (1–5.7%). Although most of the studies reviewed showed no statistical differences between manual and mechanical closure in terms of BPF development, one study, however, showed that manual closure was significantly associated with lower numbers of postoperative BPF, while another study showed that mechanical closure is significantly associated with lower incidence of BPF. When looking at the role of the learning curve and training opportunities, it seems that the surgeon's inexperience when using mechanical staples can contribute to BPF development. A surgeon's experience can play a major role in the prevention of BPF development in patients having manual closure. Manual closure can provide a cheap and reliable technique when compared with costs incurred from using staplers, it is applicable in all situations and can be taught to surgeons in training with an acceptable risk. However, there is a lack of evidence to suggest that manual closure is better than mechanical stapler closure following anatomical lung resection. PMID:24351508
von Renteln, Daniel; Schmidt, Arthur; Vassiliou, Melina C; Gieselmann, Maria; Caca, Karel
2009-10-01
Secure endoscopic closure of transgastric natural orifice transluminal endoscopic surgery (NOTES) access is of paramount importance. The over-the-scope clip (OTSC) system has previously been shown to be effective for NOTES gastrotomy closure. To compare OTSC gastrotomy closure with surgical closure. Randomized, controlled animal study. Animal facility laboratory. Thirty-six female domestic pigs. Gastrotomies were created by using a needle-knife and an 18-mm balloon. The animals were subsequently randomized to either open surgical repair with interrupted sutures or endoscopic repair with 12-mm OTSCs. In addition, pressurized leak tests were performed in ex vivo specimens of 18-mm scalpel incisions closed with suture (n = 14) and of intact stomachs (n = 10). The mean time for endoscopic closure was 9.8 minutes (range 3-22, SD 5.5). No complications occurred during either type of gastrotomy closure. At necropsy, examination of all OTSC and surgical closures demonstrated complete sealing of gastrotomy sites without evidence of injury to adjacent organs. Pressurized leak tests showed a mean burst pressure of 83 mm Hg (range 30-140, SD 27) for OTSC closures and 67 mm Hg (range 30-130, SD 27.7) for surgical sutures. Ex vivo hand-sewn sutures of 18-mm gastrotomies (n = 14) exhibited a mean burst pressure of 65 mm Hg (range 20-140, SD 31) and intact ex vivo stomachs (n = 10) had a mean burst pressure of 126 mm Hg (range 90-170, SD 28). The burst pressure of ex vivo intact stomachs was significantly higher compared with OTSC closures (P < .01), in vivo surgical closures (P < .01), and ex vivo hand-sewn closures (P < .01). There was a trend toward higher burst pressures in the OTSC closures compared with surgical closures (P = .063) and ex vivo hand-sewn closures (P = .094). In vivo surgical closures demonstrated similar burst pressures compared with ex vivo hand-sewn closures (P = .848). Nonsurvival setting. Endoscopic closure by using the OTSC system is comparable to surgical closure in a nonsurvival porcine model. This technique is easy to perform and is suitable for NOTES gastrotomy closure.
ERIC Educational Resources Information Center
Gross, Rosalind L.; White, Harry E.
This publication describes a selected group of child-resistant closures used in packaging five categories of medicine and household products. The material in the document was collected to train survey personnel to identify closures for a planned household study of the effectiveness of child-resistant packaging. The 39 closures described are of…
Airborne Sunphotometry of African Dust and Marine Boundary Layer Aerosols in PRIDE
NASA Technical Reports Server (NTRS)
Livingston, John M.; Redemann, Jens; Russell, Philip; Schmid, Beat; Reid, Jeff; Pilewskie, Peter; Hipskind, R. Stephen (Technical Monitor)
2000-01-01
The Puerto Rico Dust Experiment (PRIDE) was conducted during summer 2000 to study the radiative, microphysical and transport properties of Saharan dust in the Caribbean region. During PRIDE, NASA Ames Research Center's six-channel airborne autotracking sunphotometer (AATS-6) was operated aboard a Piper Navajo airplane based at Roosevelt Roads Naval Station on the northeast coast of Puerto Rico. AATS-6 measurements were taken during 21 science flights off the coast of Puerto Rico in the western Caribbean. Data were acquired within and above the Marine Boundary Layer (MBL) and the Saharan Aerosol Layer (SAL) up to 5.5 km altitude tinder a wide range of dust loadings. Aerosol optical depth (AOD) spectra and columnar water vapor (CWV) values have been calculated from the AATS-6 measurements by using sunphotometer calibration data obtained at Mauna Loa Observatory (3A kin ASL) before (May) and after (October) PRIDE. Mid-visible AOD values measured near the surface during PRIDE ranged from 0.07 on the cleanest day to 0.55 on the most turbid day. Values measured above the MBL were as high as 0.35; values above the SAL were as low as 0.01. The fraction of total column AOD due to Saharan dust cannot be determined precisely from AATS-6 AOD data alone due to the uncertainty in the extent of vertical mixing of the dust down through the MBL. However, analyses of ground-based and airborne in-situ aerosol sampling measurements and ground-based aerosol lidar backscatter data should yield accurate characterization of the vertical mixing that will enable calculation of the Saharan dust AOD component from the sunphotometer data. Examples will be presented showing measured AATS-6 AOD spectra, calculated aerosol extinction and water vapor density vertical profiles, and aerosol size distributions retrieved by inversion of the AOD spectra. Near sea-surface AOD spectra acquired by AATS-6 during horizontal flight legs at 30 m ASL are available for validation of AOD derived from coincident satellite sensor (TOMS, MODIS, MISR) measurements. AATS-6 AOD data acquired during numerous aircraft ascents and descents through the MBL and the SAL should permit atmospheric column closure analyses with respect to aerosol optical depth, extinction, and size distribution by comparison with coincident aircraft-based in-situ particle size distribution measurements and ground-based (Cabras Island, Puerto Rico) micropulse lidar aerosol backscatter measurements. The aerosol information derived from the column closure analyses can be used subsequently to calculate radiative flux changes, which can then be compared with coincident spectral flux measurements taken from aboard the aircraft with a solar spectral flux radiometer.
Silicone absorption of elastomeric closures--an accelerated study.
Degrazio, F L; Hlobik, T; Vaughan, S
1998-01-01
There is a trend in the parenteral industry to move from the use of elastomeric closures which are washed, siliconized, dried and sterilized in-house at the pharmaceutical manufacturers' site to pre-prepared closures purchased from the closure supplier. This preparation can consist of washing to reduce particle-load and bioburden, siliconization, placement in ready-to-sterilize bags and may eventually extend to sterilization by steam autoclave or gamma irradiation. Since silicone oil lubrication is critical to the processability/machinability of closures, research was designed to investigate this phenomenon in closures prepared using the Westar RS (Ready-to-Sterilize) process. This paper presents the data gathered in a study of the characteristic of silicone absorption into elastomeric closures under accelerated conditions. Variables such as silicone viscosity, rubber formulation, effect of sterilization and others are considered.
NASA Technical Reports Server (NTRS)
Livingston, John M.; Kapustin, Vladimir N.; Schmid, Beat; Russell, Philip B.; Quinn, Patricia K.; Bates, Timothy S.; Durkee, Philip A.; Smith, Peter J.; Freudenthaler, Volker; Wiegner, Matthias;
2000-01-01
Analyses of aerosol optical depth (AOD) and colurnmn water vapor (CWV) measurements acquired with NASA Ames Research Center's 6-channel Airborne Tracking Sunphotometer (AATS-6) operated aboard the R/V Professor Vodyanitskiy during the 2nd Aerosol Characterization Experiment (ACE-2) are discussed. Data are compared with various in situ and remote measurements for selected cases. The focus is on 10 July, when the Pelican airplane flew within 70 km of the ship near the time of a NOAA-14/AVHRR satellite overpass and AOD measurements with the 14-channel Ames Airborne Tracking Sunphotometer (AATS-14) above the marine boundary layer (MBL) permitted calculation of AOD within the MBL from the AATS-6 measurements. A detailed column closure test is performed for MBL AOD on 10 July by comparing the AATS-6 MBL AODs with corresponding values calculated by combining shipboard particle size distribution measurements with models of hygroscopic growth and radiosonde humidity profiles (plus assumptions on the vertical profile of the dry particle size distribution and composition). Large differences (30-80% in the mid-visible) between measured and reconstructed AODs are obtained, in large part because of the high sensitivity of the closure methodology to hygroscopic growth models, which vary considerably and have not been validated over the necessary range of particle size/composition distributions. The wavelength dependence of AATS-6 AODs is compared with the corresponding dependence of aerosol extinction calculated from shipboard measurements of aerosol size distribution and of total scattering mearured by a shipboard integrating nephelometer for several days. Results are highly variable, illustrating further the great difficulty of deriving column values from point measurements. AATS-6 CWV values are shown to agree well with corresponding values derived from radiosonde measurements during 8 soundings on 7 days and also with values calculated from measurements taken on 10 July with the AATS-14 and the University of Washington Passive Humidigraph aboard the Pelican.
The timing of ostomy closure in infants with necrotizing enterocolitis: a systematic review.
Struijs, Marie-Chantal; Sloots, Cornelius E J; Hop, Wim C J; Tibboel, Dick; Wijnen, Rene M H
2012-07-01
The optimal timing of ostomy closure is a matter of debate. We performed a systematic review of outcomes of early ostomy closure (EC, within 8 weeks) and late ostomy closure (LC, after 8 weeks) in infants with necrotizing enterocolitis. PubMed, EMbase, Web-of-Science, and Cinahl were searched for studies that detailed time to ostomy closure, and time to full enteral nutrition (FEN) or complications after ostomy closure. Patients with Hirschsprung's disease or anorectal malformations were excluded. Analysis was performed using SPSS 17 and RevMan 5. Of 778 retrieved articles, 5 met the inclusion criteria. The median score for study quality was 9 [range 8-14 on a scale of 0 to 32 points (Downs and Black, J Epidemiol Community Health 52:377-384, 1998)]. One study described mean time to FEN: 19.1 days after EC (n = 13) versus 7.2 days after LC (n = 24; P = 0.027). Four studies reported complication rates after ostomy closure, complications occurred in 27% of the EC group versus 23% of the LC group. The combined odds ratio (LC vs. EC) was 1.1 [95% CI 0.5, 2.5]. Evidence that supports early or late closure is scarce and the published articles are of poor quality. There is no significant difference between EC versus LC in the complication rate. This systematic review supports neither early nor late ostomy closure.
Influence of glottal closure configuration on vocal efficacy in young normal-speaking women.
Schneider, Berit; Bigenzahn, Wolfgang
2003-12-01
Posterior closure insufficiency of the glottis is often mentioned in connection with permanent voice disorders. Recently published studies have revealed that an incomplete closure of the glottis can be found also in normal-speaking voices, especially in women. However, the effect of glottal closure configuration on vocal efficacy is not sufficiently clarified. The purpose of this study was to determine the effect of glottal closure configuration on singing and speaking voice characteristics. Overall, 520 young female normal-speaking subjects were examined by videostroboscopy for different phonation conditions in the combination of soft, loud, low, and/or high phonation and by voice range profile measurements. According to the videostroboscopic analysis, the subjects were subdivided into four groups: complete closure of the vocal folds already in soft phonation (group 1), closure of the vocal fold with increasing intensity (group 2), persistent closure insufficiencies despite increasing intensity (group 3), and hourglass-shaped closure in subjects with vocal nodules (group 4). Subjects in which the glottal closure could not be evaluated sufficiently were subclassified into group 5 (missing values). Selected criteria of the singing and speaking voice were evaluated and statistically processed according to the mentioned subclassification. Group 1 reached significantly the highest sound pressure levels (SPLmax) for the singing voice as well as for the shouting voice. Group 3 showed a limited capacity to increase the intensity of the singing and speaking voice. The results gathered in this study objectify the relationship of insufficient glottal closure and reduced vocal capabilities. As long as no conclusive data on long-term consequences of insufficient glottal closure are available, a prophylactic improvement of the laryngeal situation especially in female professional voice users by voice therapy should be recommended.
Lasp1 misexpression influences chondrocyte differentiation in the vertebral column.
Hermann-Kleiter, Natascha; Ghaffari-Tabrizi, Nassim; Blumer, Michael J F; Schwarzer, Christoph; Mazur, Magdalena A; Artner, Isabella
2009-01-01
The mouse mutant wavy tail Tg(Col1a1-lacZ)304ng was created through transgene insertion and exhibits defects of the vertebral column. Homozygous mutant animals have compressed tail vertebrae and wedge-shaped intervertebral discs, resulting in a meandering tail. Delayed closure of lumbar neural arches and lack of processus spinosi have been observed; these defects become most prominent during the transition from cartilage to bone. The spina bifida was resistant to folic acid treatment, while retinoic acid administration caused severe skeletal defects in the mutant, but none in wild type control animals. The transgene integrated at chromosome 11 band D, in an area of high gene density. The insertion site was located between the transcription start sites of the Rpl23 and Lasp1 genes. LASP1 (an actin binding protein involved in cell migration and survival) was found to be produced in resting and hypertrophic chondrocytes in the vertebrae. In mutant vertebrae, temporal and spatial misexpression of Lasp1 was observed, indicating that alterations in Lasp1 transcription are most likely responsible for the observed phenotype. These data reveal a yet unappreciated role of Lasp1 in chondrocyte differentiation during cartilage to bone transition.
Ethnic differences in primary angle-closure glaucoma.
Yip, Jennifer L Y; Foster, Paul J
2006-04-01
Observational studies from different countries have shown that populations of East Asian origin have a higher frequency of primary angle-closure glaucoma compared with those of European or African descent. As half of all cases of glaucoma reside in Asia, and with primary angle-closure glaucoma carrying a higher rate of visual morbidity, primary angle-closure glaucoma poses an important public health problem; however, the inconsistent use of techniques and definitions to detect and diagnose primary angle-closure glaucoma has resulted in difficulties in interpreting the accuracy and comparability of such data. Therefore it is important to review these studies in the light of a consistent classification system. There are increasing reports that support previous findings on the incidence and prevalence of primary angle-closure glaucoma in different ethnic groups. There have also been further investigations into the mechanism and natural history of primary angle-closure glaucoma in Asian populations. International investigations into primary angle-closure glaucoma have demonstrated reproducible evidence that ethnic variations do exist. Cross-sectional studies in this area have also suggested that differences in anterior chamber depth, together with its association with peripheral anterior synechiae, may be part of the underlying mechanism behind these differences. The ideas generated need to be further explored with longitudinal data of changes in anterior chamber depth and peripheral anterior synechiae in different populations. The detailed mechanisms behind the development of angle-closure and primary angle-closure glaucoma should also be investigated.
Gupta, Saurabh Kumar; Krishnamoorthy, Km; Tharakan, Jaganmohan A; Sivasankaran, S; Sanjay, G; Bijulal, S; Anees, T
2011-07-01
To evaluate the effect of percutaneous closure of patent ductus arteriosus (PDA) on left ventricular (LV) systolic and diastolic function in children. Limited studies are available on alteration in LV hemodynamics, especially diastolic function, after PDA closure. Thirty-two consecutive children with isolated PDA treated by trans-catheter closure were studied. The LV systolic and diastolic function were assessed by two-dimensional (2D) echocardiography and tissue Doppler imaging 1 day before the PDA closure, on day 1, and on follow-up. At baseline, none of the patients had LV systolic dysfunction. On day 1 post-PDA closure, 8 (25%) children developed LV systolic dysfunction. The baseline LV ejection fraction (LVEF), LV end-systolic dimension (LVESD), and PDA diastolic gradient predicted the post-closure LVEF. Patients who developed post-closure LV systolic dysfunction had poorer LV diastolic function than those who did not. LV diastolic properties improved after PDA closure; however, the improvement in LV diastolic properties lagged behind the improvement in the LV systolic function. All children were asymptomatic and had normal LVEF on follow up of >3 months. Percutaneous closure of PDA is associated with the reversible LV systolic dysfunction. Improvement in the LV diastolic function lags behind that in the LV systolic function.
Acosta, Stefan; Björck, Martin; Petersson, Ulf
2017-01-01
The aim of this paper was to review the literature on vacuum-assisted wound closure and mesh-mediated fascial traction (VAWCM) in open abdomen therapy. It was designed as systematic review of observational studies. A Pub Med, EMBASE and Cochrane search from 2007/01-2016/07 was performed combining the Medical Subject Headings "vacuum", "mesh-mediated fascial traction", "temporary abdominal closure", "delayed abdominal closure", "open abdomen", "abdominal compartment syndrome", "negative pressure wound therapy" or "vacuum assisted wound closure". Eleven original studies were found including patients numbering from 7 to 111. Six studies were prospective and five were retrospective. Nine studies were on mixed surgical (n = 9), vascular (n = 6) and trauma (n = 6) patients, while two were exclusively on vascular patients. The primary fascial closure rate per protocol varied from 80-100%. The time to closure of the open abdomen varied between 9-32 days. The entero-atmospheric fistula rate varied from 0-10.0%. The in-hospital survival rate varied from 57-100%. In the largest prospective study, the incisional hernia rate among survivors at 63 months of median follow-up was 54% (27/50), and 16 (33%) repairs out of 48 incisional hernias were performed throughout the study period. The study patients reported lower short form health survey (SF-36) scores than the mean reference population, mainly dependent on the prevalence of major co-morbidities. There was no difference in SF-36 scores or a modified ventral hernia pain questionnaire (VHPQ) at 5 years of follow up between those with versus those without incisional hernias. A high primary fascial closure rate can be achieved with the vacuum-assisted wound closure and meshmediated fascial traction technique in elderly, mainly non-trauma patients, in need of prolonged open abdomen therapy.
Analytical and Experimental Study of Near-Threshold Interactions Between Crack Closure Mechanisms
NASA Technical Reports Server (NTRS)
Newman, John A.; Riddell, William T.; Piascik, Robert S.
2003-01-01
The results of an analytical closure model that considers contributions and interactions between plasticity-, roughness-, and oxide-induced crack closure mechanisms are presented and compared with experimental data. The analytical model is shown to provide a good description of the combined influences of crack roughness, oxide debris, and plasticity in the near-threshold regime. Furthermore, analytical results indicate that closure mechanisms interact in a non-linear manner such that the total amount of closure is not the sum of closure contributions for each mechanism.
NASA Technical Reports Server (NTRS)
Russell, P. B.; Bergstrom, Robert W.; Schmid, B.; Livingston, J. M.
2000-01-01
We estimate the impact of North Atlantic aerosols on the net short-wave flux at the tropopause by combining satellite-derived aerosol optical depth (AOD) maps with model aerosol properties determined via closure analyses in TARFOX and ACE 2. We exclude African dust, primarily by restricting latitudes to 25-60 N. The analyses use in situ aerosol composition measurements and air- and ship-borne sun-photometer measurements of AOD spectra. The aerosol model yields computed flux sensitivities (dFlux/dAOD) that agree with measurements by airborne flux radiometers in TARFOX. Its midvisible single-scattering albedo is 0.9. which is in the range obtained from in situ measurements of scattering and absorption in both TARFOX and ACE 2. Combining satellite-derived AOD maps with the aerosol model yields maps of 24-hour average net radiative flux changes. For simultaneous AVHRR, radiance measurements exceeded the sunphotometer AODs by about 0.04. However. shipboard sunphotometer and AVHRR AODs agreed Within 0.02 for data acquired during satellite overflights on two other days. We discuss attempts to demonstrate column closure within the MBL by comparing shipboard sunphotometer AODs and values calculated from simultaneous shipboard in-situ aerosol size distribution measurements. These comparisons were mostly unsuccessful, but they illustrate the difficulties inherent in this type of closure analysis. Specifically, AODs derived from near-surface in-situ size distribution measurements are extremely sensitive to the assumed hygroscopic growth model that itself requires an assumption of particle composition as a function of height and size, to the radiosonde-measured relative humidity, and to the vertical profile of particle number. We investigate further the effects of hygroscopic particle growth within the MBL by using shipboard lidar aerosol backscatter profiles together with the sunphotometer AOD.
Management of hidradenitis suppurativa wounds with an internal vacuum-assisted closure device.
Chen, Y Erin; Gerstle, Theodore; Verma, Kapil; Treiser, Matthew D; Kimball, Alexandra B; Orgill, Dennis P
2014-03-01
Hidradenitis suppurativa is a chronic, debilitating disease that is difficult to treat. Once medical management fails, wide local excision offers the best chance for cure. However, the resultant wound often proves too large or contaminated for immediate closure. The authors performed a retrospective chart review of hidradenitis cases managed surgically between 2005 and 2010. Data collected included patient characteristics, management method, and outcomes. Approximately half of the patients received internal vacuum-assisted closure therapy using the vacuum-assisted closure system and delayed closure and half of the patients received immediate primary closure at the time of their excision. Delayed closure consisted of closing the majority of the wound in a linear fashion following internal vacuum-assisted closure while accepting healing by means of secondary intention for small wound areas. Patients managed with internal vacuum-assisted closure had wounds on average four times larger in area than patients managed without internal vacuum-assisted closure. In both groups, all wounds were eventually closed primarily. Healing times averaged 2.2 months with internal vacuum-assisted closure and 2.7 months without. At an average follow-up time of 2.3 months, all patients with internal vacuum-assisted closure had no recurrence of their local disease. Severe hidradenitis presents a treatment challenge, as surgical excisions are often complicated by difficult closures and unsatisfactory recurrence rates. This study demonstrates that wide local excision with reasonable outcomes can be achieved using accelerated delayed primary closure. This method uses internal vacuum-assisted closure as a bridge between excision and delayed primary closure, facilitating closure without recurrence in large, heavily contaminated wounds. Therapeutic, III.
Household responses to school closure resulting from outbreak of influenza B, North Carolina.
Johnson, April J; Moore, Zack S; Edelson, Paul J; Kinnane, Lynda; Davies, Megan; Shay, David K; Balish, Amanda; McCarron, Meg; Blanton, Lenee; Finelli, Lyn; Averhoff, Francisco; Bresee, Joseph; Engel, Jeffrey; Fiore, Anthony
2008-07-01
School closure is a proposed strategy for reducing influenza transmission during a pandemic. Few studies have assessed how families respond to closures, or whether other interactions during closure could reduce this strategy's effect. Questionnaires were administered to 220 households (438 adults and 355 children) with school-age children in a North Carolina county during an influenza B virus outbreak that resulted in school closure. Closure was considered appropriate by 201 (91%) households. No adults missed work to solely provide childcare, and only 22 (10%) households required special childcare arrangements; 2 households incurred additional costs. Eighty-nine percent of children visited at least 1 public location during the closure despite county recommendations to avoid large gatherings. Although behavior and attitudes might differ during a pandemic, these results suggest short-term closure did not cause substantial hardship for parents. Pandemic planning guidance should address the potential for transmission in public areas during school closure.
Kawai, Manabu; Tani, Masaji; Okada, Ken-ichi; Hirono, Seiko; Miyazawa, Motoki; Shimizu, Astusi; Kitahata, Yuji; Yamaue, Hiroki
2013-09-01
The appropriate surgical stump closure after distal pancreatectomy (DP) is still controversial. This study investigated the benefits and risks of stapler closure during DP. The risk factors of pancreatic fistulas were investigated in 122 DPs among 3 types of stump closure: hand-sewn suture (n = 32), bipolar scissors (n = 45), and stapler closure (n = 45). There was no significant difference in the incidence of pancreatic fistula between the 3 types of stump closure (hand-sewn suture [44%] vs bipolar scissors [37.7%] vs stapler closure [35.5%]). By using receiver operating characteristics curves, 12 mm was the best cutoff value of the thickness of the pancreas for pancreatic fistulas after DP using stapler closure. Three factors (ie, male sex, body mass index >25 kg/m(2), and stapler closure) were independent risk factors of pancreatic fistulas after DP with a pancreas thicker than 12 mm. A pancreas thicker than 12 mm significantly increased the incidence of pancreatic fistulas after DP using stapler closure. Copyright © 2013 Elsevier Inc. All rights reserved.
Stapler vs suture closure of pancreatic remnant after distal pancreatectomy: a meta-analysis.
Zhou, Wei; Lv, Ran; Wang, Xianfa; Mou, Yiping; Cai, Xiujun; Herr, Ingrid
2010-10-01
Suture closure and stapler closure of the pancreatic remnant after distal pancreatectomy are the techniques used most often. The ideal choice remains a matter of debate. Five bibliographic databases covering 1970 to July 2009 were searched. Sixteen articles met the inclusion criteria. Stapler closure was performed in 671 patients, while suture closure was conducted in 1,615 patients. The pancreatic fistula rate ranged from 0% to 40.0% for stapler closure of the pancreatic stump and from 9.3% to 45.7% for the suture closure technique. There were no significant difference between the stapler and suture closure groups with respect to the pancreatic fistula formation rate (22.1% vs 31.2%; odds ratio, .85; 95% confidence interval, .66-1.08), although there was a trend toward favoring stapler closure. In 4 studies including 437 patients, stapler closure was associated with a trend (not statistically significant) toward a reduction in intra-abdominal abscess (odds ratio, .53; 95% confidence interval, .24-1.15). No significant differences occur between suture and stapler closure with respect to the pancreatic fistula or intra-abdominal abscess after distal pancreatectomy, though there is a trend favoring stapler closure. Copyright © 2010 Elsevier Inc. All rights reserved.
Kanwar, Siddak M; Noheria, Amit; DeSimone, Christopher V; Rabinstein, Alejandro A; Asirvatham, Samuel J
2016-03-01
We analyzed the literature to assess the coincidental impact on migraines of transcatheter patent foramen ovale (PFO) closure performed for secondary stroke prevention. We searched Medline, EMBASE, and the Cochrane database for studies published up until August 2013. We included English-language studies that provided information on complete resolution or improvement in migraine headaches following PFO closure. Two study authors identified 375 original articles and both independently reviewed 32 relevant manuscripts. Data including study methodology, inclusion criteria, PFO closure and migraine outcomes were extracted manually from all eligible studies. Pooled odds (and probability) of resolution or improvement of migraine headaches were calculated using random-effects models. Twenty studies were analyzed. Most were uncontrolled studies that included a small number of patients with cryptogenic stroke who had undergone PFO closure and had variable time of followup. The probability of complete resolution of migraine with PFO closure (18 studies, 917 patients) was 0.46 (95% confidence interval 0.39, 0.53) and of any improvement in migraine (17 studies, 881 patients) was 0.78 (0.74, 0.82). There was evidence for publication bias in studies reporting on improvement in migraines (Begg's p=0.002), but not for studies on complete resolution of migraine (p=0.3). In patients with aura, the probability of complete resolution of migraine post-PFO closure was 0.54 (0.43, 0.65), and in those without aura, complete resolution occurred in 0.39 (0.29, 0.51). Among patients with unexplained stroke and migraine undergoing transcatheter PFO closure, resolution of headaches occurred in a majority of patients with aura and for a smaller proportion of patients without aura.
Crack closure, a literature study
NASA Astrophysics Data System (ADS)
Holmgren, M.
1993-08-01
In this report crack closure is treated. The state of the art is reviewed. Different empirical formulas for determining the crack closure are compared with each other, and their benefits are discussed. Experimental techniques for determining the crack closure stress are discussed, and some results from fatigue tests are also reported. Experimental data from the literature are reported.
Sankaran, Sindhuja; Szumowska, Ewa; Kossowska, Małgorzata
2017-01-01
Previous studies have demonstrated that the need for closure (NFC), which refers to an individual's aversion toward uncertainty and the desire to quickly reduce it, leads to reluctance to invest effort in judgments and decision making. However, we argue that NFC may lead to either an increase or a decrease in effort depending on the availability of easy vs. difficult means to achieve closure and perceived importance of the task goal. We found that when closure could be achieved via both less and more demanding means, NFC was associated with decreased effort unless the task was perceived as important (Study 1). However, when attaining closure was possible via demanding means only, NFC was associated with increased effort, regardless of the task importance (Study 2). Moreover, NFC was related to choosing a more instrumental strategy for the goal of closure, even if this strategy required effort (Study 3). The results are discussed in the light of cognitive energetics theory.
Griffin, Brian M.; Larson, Vincent E.
2016-11-25
Microphysical processes, such as the formation, growth, and evaporation of precipitation, interact with variability and covariances (e.g., fluxes) in moisture and heat content. For instance, evaporation of rain may produce cold pools, which in turn may trigger fresh convection and precipitation. These effects are usually omitted or else crudely parameterized at subgrid scales in weather and climate models.A more formal approach is pursued here, based on predictive, horizontally averaged equations for the variances, covariances, and fluxes of moisture and heat content. These higher-order moment equations contain microphysical source terms. The microphysics terms can be integrated analytically, given a suitably simplemore » warm-rain microphysics scheme and an approximate assumption about the multivariate distribution of cloud-related and precipitation-related variables. Performing the integrations provides exact expressions within an idealized context.A large-eddy simulation (LES) of a shallow precipitating cumulus case is performed here, and it indicates that the microphysical effects on (co)variances and fluxes can be large. In some budgets and altitude ranges, they are dominant terms. The analytic expressions for the integrals are implemented in a single-column, higher-order closure model. Interactive single-column simulations agree qualitatively with the LES. The analytic integrations form a parameterization of microphysical effects in their own right, and they also serve as benchmark solutions that can be compared to non-analytic integration methods.« less
Regional modulation of the response to glutathione in Hydra vulgaris.
Pierobon, Paola
2015-07-01
In the presence of prey, or upon exposure to reduced glutathione (GSH), Hydra polyps open a mouth to ingest the captured prey and close it after feeding; at rest the mouth is not evident. In previous papers we have shown that GABA, glycine and NMDA modulate the mechanisms of mouth closure through ligand-gated-ion-channel receptors that are similar to their mammalian analogues in terms of biochemical and pharmacological properties. In order to study the regional distribution of these receptors, we have applied the GSH assay to polyps amputated at different levels of the body column. The response to 1-10 µmol l(-1) GSH of polyps lacking either peduncle and foot or the entire body columns (heads) was not different from control, whole animals. In the presence of GABA or muscimol, duration of the response was significantly decreased in heads; the decrease was suppressed by the GABA antagonists gabazine and bicuculline. By contrast, in animals lacking peduncle and foot, duration of the response did not vary upon GABA administration. Conversely, in the presence of glycine, duration of the response in heads preparations was similar to control, whereas in footless polyps, it was significantly reduced. The decrease was mimicked by the glycine agonists taurine and β-alanine, and counteracted by strychnine. These results suggest a regional distribution of receptors to GABA and glycine in the neuromuscular circuitry modulating the feeding behaviour. © 2015. Published by The Company of Biologists Ltd.
Stenberg, Erik; Szabo, Eva; Ottosson, Johan; Thorell, Anders; Näslund, Ingmar
2018-01-01
Mesenteric defect closure in laparoscopic gastric bypass surgery has been reported to reduce the risk for small bowel obstruction. Little is known, however, about the effect of mesenteric defect closure on patient-reported outcome. The aim of the present study was to see if mesenteric defect closure affects health-related quality-of-life (HRQoL) after laparoscopic gastric bypass. Patients operated at 12 centers for bariatric surgery participated in this randomized two-arm parallel study. During the operation, patients were randomized to closure of the mesenteric defects or non-closure. This study was a post-hoc analysis comparing HRQoL of the two groups before surgery, at 1 and 2 years after the operation. HRQoL was estimated using the short form 36 (SF-36-RAND) and the obesity problems (OP) scale. Between May 1, 2010, and November 14, 2011, 2507 patients were included in the study and randomly assigned to mesenteric defect closure (n = 1259) or non-closure (n = 1248). In total, 1619 patients (64.6%) reported on their HRQoL at the 2-year follow-up. Mesenteric defect closure was associated with slightly higher rating of social functioning (87 ± 22.1 vs. 85 ± 24.2, p = 0.047) and role emotional (85 ± 31.5 vs. 82 ± 35.0, p = 0.027). No difference was seen on the OP scale (open defects 22 ± 24.8 vs. closed defects 20 ± 23.8, p = 0.125). When comparing mesenteric defect closure with non-closure, there is no clinically relevant difference in HRQoL after laparoscopic gastric bypass surgery.
Campaign datasets for Two-Column Aerosol Project (TCAP)
Berg,Larry; Mei,Fan; Cairns,Brian; Chand,Duli; Comstock,Jennifer; Cziczo,Daniel; Hostetler,Chris; Hubbe,John; Long,Chuck; Michalsky,Joseph; Pekour,Mikhail; Russell,Phil; Scott,Herman; Sedlacek,Arthur; Shilling,John; Springston,Stephen; Tomlinson,Jason; Watson,Thomas; Zelenyuk-Imre,Alla
2013-12-30
This campaign was designed to provide a detailed set of observations with which to 1) perform radiative and cloud condensation nuclei (CCN) closure studies, 2) evaluate a new retrieval algorithm for aerosol optical depth (AOD) in the presence of clouds using passive remote sensing 3) extend a previously developed technique to investigate aerosol indirect effects, and 4) evaluate the performance of a detailed regional-scale model and a more parameterized global-scale model in simulating particle activation and AOD associated with the aging of anthropogenic aerosols. To meet these science objectives, the ARM Mobile Facility (AMF) and the Mobile Aerosol Observing System (MAOS) was deployed on Cape Cod, Massachusetts for a 12-month period starting in the summer of 2012 in order to quantify aerosol properties, radiation and cloud characteristics at a location subject to both clear- and cloudy- conditions, and clean- and polluted-conditions. These observations were supplemented by two aircraft intensive observation periods (IOPS), one in the summer and a second in the winter. Each IOP required two aircraft.
Hookey, L C; Bielawska, B; Samis, A; Jalink, D; Ellis, R; Khokhotva, V; Hurlbut, D; Mercer, D
2009-06-01
The evolution of NOTES to clinical implementation has been hampered by lack of a reliable, safe, and easy-to-implement technique for closure of the opening created in accessing the peritoneum. The Queen's closure uses a combination of endoscopic clips and loop devices to seal such defects in the stomach wall. This study aimed to assess the Queen's closure in a porcine survival model. Five 30-kg pigs underwent endoscopic transgastric surgery with exploration of the peritoneum. The endoscope was then withdrawn back into the stomach and the closure performed. The animals were recovered, monitored closely, and underwent endoscopy 1 week after surgery. They were then euthanized at 2 (n = 2) and 3 (n = 3) weeks after surgery with subsequent necropsy. The mean procedure time (from intubation of the esophagus to withdrawal of the endoscope) was 79 minutes (range 45-105 minutes) with a mean time of exploration of the peritoneum of 14 minutes (range 8-25 minutes). All animals recovered well with no apparent pain, distress, or signs of infection. Endoscopic examination 1 week after surgery revealed all the closures to be intact and only identifiable by a small ulcer. At necropsy, the gastrotomy site was identifiable only by minor serosal adhesions. Histological study demonstrated full-thickness closure with minimal inflammation. The Queen's closure is a reliable and safe technique that provides full-thickness gastrotomy closure without any observed complications. The technique has proven to be transferable knowledge that holds promise for clinical implementation.
Evaluation of Container Closure System Integrity for Frozen Storage Drug Products.
Nieto, Alejandra; Roehl, Holger; Brown, Helen; Nikoloff, Jonas; Adler, Michael; Mahler, Hanns-Christian
2016-01-01
Sometimes, drug product for parenteral administration is stored in a frozen state (e.g., -20 °C or -80 °C), particularly during early stages of development of some biotech molecules in order to provide sufficient stability. Shipment of frozen product could potentially be performed in the frozen state, yet possibly at different temperatures, for example, using dry ice (-80 °C). Container closure systems of drug products usually consist of a glass vial, rubber stopper, and an aluminum crimped cap. In the frozen state, the glass transition temperature (Tg) of commonly used rubber stoppers is between -55 and -65 °C. Below their Tg, rubber stoppers are known to lose their elastic properties and become brittle, and thus potentially fail to maintain container closure integrity in the frozen state. Leaks during frozen temperature storage and transportation are likely to be transient, yet, can possibly risk container closure integrity and lead to microbial contamination. After thawing, the rubber stopper is supposed to re-seal the container closure system. Given the transient nature of the possible impact on container closure integrity in the frozen state, typical container closure integrity testing methods (used at room temperature conditions) are unable to evaluate and thus confirm container closure integrity in the frozen state. Here we present the development of a novel method (thermal physical container closure integrity) for direct assessment of container closure integrity by a physical method (physical container closure integrity) at frozen conditions, using a modified He leakage test. In this study, different container closure systems were evaluated with regard to physical container closure integrity in the frozen state to assess the suitability of vial/stopper combinations and were compared to a gas headspace method. In summary, the thermal physical container closure integrity He leakage method was more sensitive in detecting physical container closure integrity impact than gas headspace and aided identification of an unsuitable container closure system. Sometimes, drug product for parenteral administration is stored in a frozen state (e.g., -20 °C or -80 °C), particularly during early stages of development of some biotech molecules in order to provide sufficient stability. Container closure systems for drug products usually consist of a glass vial, rubber stopper, and an aluminum crimped cap. In the frozen state, the glass transition temperature (Tg) of commonly used rubber stoppers is between -55 and -65 °C. Leaks during frozen temperature storage and transportation are likely to be transient, yet they can possibly risk container closure integrity and lead to microbial contamination and sterility breach. After thawing, the rubber stopper is expected to re-seal the container closure system. Given the transient nature of the possible impact on container closure integrity in the frozen state, typical container closure integrity testing methods (used at room temperature conditions) are unable to evaluate and thus confirm container closure integrity in the frozen state. Here we present the development of a novel method (thermal container closure integrity) for direct measurement of container closure integrity by a physical method (physical container closure integrity) at frozen conditions, using a modified He leakage test. In this study, we found that the thermal container closure integrity He leakage method was more sensitive in detecting physical container closure integrity impact than gas headspace and aided identification of an unsuitable container closure system. © PDA, Inc. 2016.
Dolezel, R; Ryska, O; Kollar, M; Juhasova, J; Kalvach, J; Ryska, M; Martinek, J
2016-11-01
Both over-the-scope clip (OTSC) and KING (endoloop + clips) closures provide reliable and safe full-thickness endoscopic closure. Nevertheless, OTSC clip demonstrated significantly inferior histological healing in the short-term follow-up. To compare OTSC versus KING closure of a perforation with regard to long-term effectiveness and macroscopic and histological quality of healing. We performed a randomized experimental study with 16 mini-pigs (mean weight 43.2 ± 11.2 kg). A standardized perforation was performed on the anterior sigmoid wall. KING closure (n = 8) was attained by approximation of an endoloop fixed to the margins of a perforation with endoclips. OTSC closure (n = 8) was performed by deploying OTSC (OVESCO) over the defect. Pigs underwent a control sigmoidoscopy 8 months after the closure to assess the macroscopic quality of healing. Then, autopsy was performed and the rectosigmoid was sent for histopathological assessment. All closures were completed successfully without air leaks. The duration of closure was similar in both techniques (OTSC 17.8 ± 7.6 min vs. KING 19.6 ± 8.8 min). At autopsy, all KING closures (100 %) were healed with a flat scar without signs of leakage. Microscopically, no inflammatory changes were observed after KING closure. In the OTSC group, microscopic ulcers were present in two pigs (25 %), cryptal abscesses in three pigs (38 %) and significant neutrophil accumulation in all eight pigs (P < 0.01). Giant cell granulomas, dysplasia or abundant scarification was not observed in either group. Both OTSC and KING closures offer a long-term reliable seal of a gastrointestinal perforation without stenosis or fistulas. KING closure provides long-term histologically superior healing.
Analytic closures for M1 neutrino transport
Murchikova, E. M.; Abdikamalov, E.; Urbatsch, T.
2017-04-25
Carefully accounting for neutrino transport is an essential component of many astrophysical studies. Solving the full transport equation is too expensive for most realistic applications, especially those involving multiple spatial dimensions. For such cases, resorting to approximations is often the only viable option for obtaining solutions. One such approximation, which recently became popular, is the M1 method. It utilizes the system of the lowest two moments of the transport equation and closes the system with an ad hoc closure relation. The accuracy of the M1 solution depends on the quality of the closure. Several closures have been proposed in themore » literature and have been used in various studies. We carry out an extensive study of these closures by comparing the results of M1 calculations with precise Monte Carlo calculations of the radiation field around spherically symmetric protoneutron star models. We find that no closure performs consistently better or worse than others in all cases. The level of accuracy that a given closure yields depends on the matter configuration, neutrino type and neutrino energy. As a result, given this limitation, the maximum entropy closure by Minerbo on average yields relatively accurate results in the broadest set of cases considered in this work.« less
Concomitant surgical closure of left atrial appendage: A systematic review and meta-analysis.
Ando, Masahiko; Funamoto, Masaki; Cameron, Duke E; Sundt, Thoralf M
2018-03-12
Although percutaneous closure of the left atrial appendage is supported as a potential alternative to lifelong anticoagulation in patients with atrial fibrillation, comprehensive evidence on surgical left atrial appendage closure in heart surgery is limited. We conducted a meta-analysis of studies comparing patients who underwent open cardiac surgery with or without left atrial appendage closure. A literature search was performed on PubMed, Embase, and Cochrane Trials databases. Outcomes of interest were 30-day/in-hospital mortality and cerebrovascular accident. I 2 statistics were used to evaluate heterogeneity, and publication bias was evaluated by Begg's and Egger's tests. We reviewed 1284 articles and selected for main analysis 7 articles including 3897 patients (1963 in the left atrial appendage closure group and 1934 in the non-left atrial appendage closure group). Among the 7 studies, 3 were randomized-controlled studies, 3 were propensity-matched studies, and 1 was a case-matching study. At 30-day/in-hospital follow-up, left atrial appendage closure was significantly associated with decreased risk of mortality and cerebrovascular accident (odds ratio, 0.384, 95% confidence interval, 0.233-0.631 for mortality, and odds ratio, 0.622, 95% confidence interval, 0.388-0.998 for cerebrovascular accident). Stratified analysis demonstrated that this association was more prominent in preoperative atrial fibrillation strata. Concomitant surgical left atrial appendage closure should be considered at the time of open cardiac surgery, particularly among those in atrial fibrillation preoperatively. The benefit of left atrial appendage closure for patients not in atrial fibrillation and for those undergoing nonvalvular surgery is still unclear. Further prospective investigations are indicated. Copyright © 2018. Published by Elsevier Inc.
Modified closure technique for reducing sternal dehiscence; a clinical and in vitro assessment.
John, Lindsay C H
2008-05-01
Although the incidence of sternal dehiscence is low its mortality can be high. An alternative technique is described (modified closure) which aims to redistribute the dehiscence force into the longer longitudinal axis rather than the shorter transverse axis, thereby maximising the closure strength. Four ethibond sutures, which interlock anteriorly, are used in addition to eight transverse sternal wires. The aim of the study was to assess the modified closure using both an in vitro and a clinical study. (a) In vitro study: A weight and traction pulley system applied a force of 0.1kN to pairs of silicone rubber hemisterna approximated to each other using alternative closure techniques. The dehiscence tendency (DT) was measured as the amount of separation under tension. Using 10 pairs of hemisterna for each closure technique the measured DT for the modified closure (MC) was compare with those for each of five alternative closures (two figure-of-eight and four transverse sutures (2C), 6 (6T), 8 (8T), 10 (10T) and 12 transverse sutures (12T)). (b) Clinical study: The incidence of sternal dehiscence for the first 4 years of a consultants' practice (using 8T) was compared with the second 4 years (using MC). (a) Measured DT (mean+/-SEM), (MC: 149+/-14; 6T: 256+/-13; 8T: 223+/-9; 10T: 213+/-13; 12T: 203+/-8; 2C: 294+/-15). DT was significantly smaller for MC (p<0.003). (b) The incidence of dehiscence was significantly smaller in the second 4 years (MC) than in the first (8T): 0.2% (1/529) versus 1.6% (13/788); p=0.01 In vitro and clinical studies suggest that the modified closure technique can reduce the incidence of sternal dehiscence.
You, Tao; Yi, Kang; Ding, Zhao-Hong; Hou, Xiao-Dong; Liu, Xing-Guang; Wang, Xin-Kuan; Ge, Long; Tian, Jin-Hui
2017-06-21
Both transcatheter device closure and surgical repair are effective treatments with excellent midterm outcomes for perimembranous ventricular septal defects (pmVSDs) in children. The mini-invasive periventricular device occlusion technique has become prevalent in research and application, but evidence is limited for the assessment of transcatheter closure, mini-invasive closure and open-heart surgical repair. This study comprehensively compares the efficacy, safety and costs of transcatheter closure, mini-invasive closure and open-heart surgical repair for treatment of pmVSDs in children using Bayesian network meta-analysis. A systematic search will be performed using Chinese Biomedical Literature Database, China National Knowledge Infrastructure, PubMed, EMBASE.com and the Cochrane Central Register of Controlled Trials to include random controlled trials, prospective or retrospective cohort studies comparing the efficacy, safety and costs of transcatheter closure, mini-invasive closure and open-heart surgical repair. The risk of bias for the included prospective or retrospective cohort studies will be evaluated according to the risk of bias in non-randomised studies of interventions (ROBINS-I). For random controlled trials, we will use risk of bias tool from Cochrane Handbook version 5.1.0. A Bayesian network meta-analysis will be conducted using R-3.3.2 software. Ethical approval and patient consent are not required since this study is a network meta-analysis based on published trials. The results of this network meta-analysis will be submitted to a peer-reviewed journal for publication. CRD42016053352. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
NASA Technical Reports Server (NTRS)
Russell, Philip A.; Bergstrom, Robert A.; Schmid, Beat; Livingston, John M.
2000-01-01
Aerosol effects on atmospheric radiative fluxes provide a forcing function that can change the climate in potentially significant ways. This aerosol radiative forcing is a major source of uncertainty in understanding the climate change of the past century and predicting future climate. To help reduce this uncertainty, the 1996 Tropospheric Aerosol Radiative Forcing Observational Experiment (TARFOX) and the 1997 Aerosol Characterization Experiment (ACE-2) measured the properties and radiative effects of aerosols over the Atlantic Ocean. Both experiments used remote and in situ measurements from aircraft and the surface, coordinated with overpasses by a variety of satellite radiometers. TARFOX focused on the urban-industrial haze plume flowing from the United States over the western Atlantic, whereas ACE-2 studied aerosols over the eastern Atlantic from both Europe and Africa. These aerosols often have a marked impact on satellite-measured radiances. However, accurate derivation of flux changes, or radiative forcing, from the satellite measured radiances or retrieved aerosol optical depths (AODs) remains a difficult challenge. Here we summarize key initial results from TARFOX and ACE-2, with a focus on closure analyses that yield aerosol microphysical models for use in improved assessments of flux changes. We show how one such model gives computed radiative flux sensitivities (dF/dAOD) that agree with values measured in TARFOX and preliminary values computed for the polluted marine boundary layer in ACE-2. A companion paper uses the model to compute aerosol-induced flux changes over the North Atlantic from AVHRR-derived AOD fields.
Closure of the vertebral canal in human embryos and fetuses.
Mekonen, Hayelom K; Hikspoors, Jill P J M; Mommen, Greet; Kruepunga, Nutmethee; Köhler, S Eleonore; Lamers, Wouter H
2017-08-01
The vertebral column is the paradigm of the metameric architecture of the vertebrate body. Because the number of somites is a convenient parameter to stage early human embryos, we explored whether the closure of the vertebral canal could be used similarly for staging embryos between 7 and 10 weeks of development. Human embryos (5-10 weeks of development) were visualized using Amira 3D ® reconstruction and Cinema 4D ® remodelling software. Vertebral bodies were identifiable as loose mesenchymal structures between the dense mesenchymal intervertebral discs up to 6 weeks and then differentiated into cartilaginous structures in the 7th week. In this week, the dense mesenchymal neural processes also differentiated into cartilaginous structures. Transverse processes became identifiable at 6 weeks. The growth rate of all vertebral bodies was exponential and similar between 6 and 10 weeks, whereas the intervertebral discs hardly increased in size between 6 and 8 weeks and then followed vertebral growth between 8 and 10 weeks. The neural processes extended dorsolaterally (6th week), dorsally (7th week) and finally dorsomedially (8th and 9th weeks) to fuse at the midthoracic level at 9 weeks. From there, fusion extended cranially and caudally in the 10th week. Closure of the foramen magnum required the development of the supraoccipital bone as a craniomedial extension of the exoccipitals (neural processes of occipital vertebra 4), whereas a growth burst of sacral vertebra 1 delayed closure until 15 weeks. Both the cranial- and caudal-most vertebral bodies fused to form the basioccipital (occipital vertebrae 1-4) and sacrum (sacral vertebrae 1-5). In the sacrum, fusion of its so-called alar processes preceded that of the bodies by at least 6 weeks. In conclusion, the highly ordered and substantial changes in shape of the vertebral bodies leading to the formation of the vertebral canal make the development of the spine an excellent, continuous staging system for the (human) embryo between 6 and 10 weeks of development. © 2017 Anatomical Society.
Contemporary Approach to the Diagnosis and Management of Primary Angle-Closure Disease.
Razeghinejad, M Reza; Myers, Jonathan S
2018-05-16
Primary angle closure disease spectrum varies from a narrow angle to advanced glaucoma. A variety of imaging technologies may assist the clinician in determining the pathophysiology and diagnosis of primary angle closure, but gonioscopy remains a mainstay of clinical evaluation. Laser iridotomy effectively eliminates the pupillary block component of angle closure; however, studies show that in many patients the iridocorneal angle remains narrow from underlying anatomic issues, and increasing lens size often leads to further narrowing over time. Recent studies have further characterized the role of the lens in angle closure disease, and cataract or clear lens extraction is increasingly used earlier in its management. As a first surgical step in angle closure glaucoma, lens extraction alone often effectively controls the pressure with less risk of complications than concurrent or stand alone glaucoma surgery, but may not be sufficient in more advanced or severe disease. We provide a comprehensive review on the primary angle-closure disease nomenclature, imaging, and current laser and surgical management. Copyright © 2018. Published by Elsevier Inc.
von Renteln, Daniel; Rudolph, Hans-Ulrich; Schmidt, Arthur; Vassiliou, Melina C; Caca, Karel
2010-01-01
Duodenal perforations during diagnostic upper endoscopy are rare; however, when therapeutic techniques are performed, the reported incidence is as great as 2.8%. Surgical repair is usually mandated, but it is associated with significant morbidity and mortality. To compare closure of duodenal perforations by using an over-the-scope clip (OTSC) with a surgical closure. Randomized, controlled animal study. Animal facility laboratory. Domestic pigs (24 females). Large (10-mm) duodenal perforations were created by using an endoscopic needle-knife. The animals were randomly assigned to either open surgical repair (n=12) or endoscopic closure by using the OTSC system (n=12). Pressurized leak tests were performed during necropsy. One major bleed occurred because of a liver injury during creation of the duodenotomy. Mean time for endoscopic closure was 5 minutes (range, 3-8 min; SD +/- 2). No complications occurred during any of the closure procedures. At necropsy, all OTSC and surgical closures demonstrated complete sealing of duodenotomy sites. Pressurized leak tests demonstrated a mean burst pressure of 166 mm Hg (range, 80-260; SD +/- 65) for OTSC closures and 143 mm Hg (range, 30-300, SD +/- 83) for surgical sutures. Ex vivo intact duodenal specimens exhibited a mean burst pressure of 247 mm Hg (range, 200-300; SD +/- 35), which was significantly higher compared with in vivo OTSC and surgical closures (P < .01). There were no significant differences between burst pressures of OTSC and surgical closures (P = .461). Nonsurvival setting. Endoscopic closure of duodenal perforations by using the OTSC system is comparable with surgical closure in a nonsurvival porcine model. This technique is easy to perform and seems suitable for repairing duodenal perforations. 2010 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.
Surgical impact and speech outcome at 2.5 years after one- or two-stage cleft palate closure.
Randag, Anna C; Dreise, Marieke M; Ruettermann, Mike
2014-11-01
In the ongoing discussion about timing of palate closure, it is said that early closure is favorable for speech development, but can interfere with maxillary growth. On the other hand, beneficial results on both after one-stage palate closure have also been presented. The assumption that one-stage palate closure leads to less surgical impact on the child probably contributed to the choice for this procedure in most cleft centers. However, no previous research has verified this assumption. The aim of the present study is to compare surgical impact and speech outcome at 2.5 years of age between children who underwent either one- or early two-stage palate closure. Patients underwent either one-stage palate closure between 2007 and 2010 at a median age of 10.8 months (group 1, n=24) or early two-stage closure before 2007 at median ages of 10.4 and 18.2 months, respectively (group 2, n=24). Surgical impact was compared between the two groups by means of duration of surgery, length of hospital stay and number of post-operative complications. Speech outcome was compared by means of resonance problems, nasal air emission, articulation and intelligibility, all assessed at a median age of 2.5 years. The one-stage closure group showed significantly shorter duration of surgery and length of hospital stay (p<0.001 and p=0.001, respectively) and significantly better articulation (p=0.029) than the early two-stage closure group. One-stage palate closure is preferable over early two-stage palate closure with regard to surgical impact and speech development. More extensive, prospective studies, in which maxillary growth is taken into account, should be conducted. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Kääriäinen, M; Kuuskeri, M; Helminen, M; Kuokkanen, H
2017-06-01
The open abdomen technique is a standard procedure in the treatment of intra-abdominal catastrophe. Achieving primary abdominal closure within the initial hospitalization is a main objective. This study aimed to analyze the success of closure rate and the effect of negative pressure wound therapy, mesh-mediated medial traction, and component separation on the results. We present the treatment algorithm used in our institution in open abdomen situations based on these findings. Open abdomen patients (n = 61) treated in Tampere University Hospital from May 2005 until October 2013 were included in the study. Patient characteristics, treatment prior to closure, closure technique, and results were retrospectively collected and analyzed. The first group included patients in whom direct or bridged fascial closure was achieved, and the second group included those in whom only the skin was closed or a free skin graft was used. Background variables and variables related to surgery were compared between groups. Most of the open abdomen patients (72.1%) underwent fascial defect repair during the primary hospitalization, and 70.5% of them underwent direct fascial closure. Negative pressure wound therapy was used as a temporary closure method for 86.9% of the patients. Negative pressure wound therapy combined with mesh-mediated medial traction resulted in the shortest open abdomen time (p = 0.039) and the highest fascial repair rate (p = 0.000) compared to negative pressure wound therapy only or no negative pressure wound therapy. The component separation technique was used for 11 patients; direct fascial closure was achieved in 5 and fascial repair by bridging the defect with mesh was achieved in 6. A total of 8 of 37 (21.6%) patients with mesh repair had a mesh infection. The negative pressure wound therapy combined with mesh-mediated medial traction promotes definitive fascial closure with a high closure rate and a shortened open abdomen time. The component separation technique can be used to facilitate fascial repair but it does not guarantee direct fascial closure in open abdomen patients.
Guinea pig ductus arteriosus. II - Irreversible closure after birth.
NASA Technical Reports Server (NTRS)
Fay, F. S.; Cooke, P. H.
1972-01-01
To investigate the mechanism underlying irreversibility of ductal closure after birth, studies were undertaken to determine the exact time course for the onset of irreversible closure of the guinea pig ductus arteriosus. Parallel studies of the reactivity of ductal smooth muscle to oxygen and studies of the postpartum cellular changes within the vessel were also carried out.
Improving the Safety of Moving Lane Closures
DOT National Transportation Integrated Search
2009-06-01
Moving lane closures are an increasingly utilized and inherently hazardous traffic control procedure for highway : maintenance and operations activities. To improve the safety of moving lane closures for workers and motorists, : this research studied...
Full closure strategic analysis.
DOT National Transportation Integrated Search
2014-07-01
The full closure strategic analysis was conducted to create a decision process whereby full roadway : closures for construction and maintenance activities can be evaluated and approved or denied by CDOT : Traffic personnel. The study reviewed current...
Platelets contribute to postnatal occlusion of the ductus arteriosus.
Echtler, Katrin; Stark, Konstantin; Lorenz, Michael; Kerstan, Sandra; Walch, Axel; Jennen, Luise; Rudelius, Martina; Seidl, Stefan; Kremmer, Elisabeth; Emambokus, Nikla R; von Bruehl, Marie-Luise; Frampton, Jon; Isermann, Berend; Genzel-Boroviczény, Orsolya; Schreiber, Christian; Mehilli, Julinda; Kastrati, Adnan; Schwaiger, Markus; Shivdasani, Ramesh A; Massberg, Steffen
2010-01-01
The ductus arteriosus (DA) is a fetal shunt vessel between the pulmonary artery and the aorta that closes promptly after birth. Failure of postnatal DA closure is a major cause of morbidity and mortality particularly in preterm neonates. The events leading to DA closure are incompletely understood. Here we show that platelets have an essential role in DA closure. Using intravital microscopy of neonatal mice, we observed that platelets are recruited to the luminal aspect of the DA during closure. DA closure is impaired in neonates with malfunctioning platelet adhesion or aggregation or with defective platelet biogenesis. Defective DA closure resulted in a left-to-right shunt with increased pulmonary perfusion, pulmonary vascular remodeling and right ventricular hypertrophy. Our findings indicate that platelets are crucial for DA closure by promoting thrombotic sealing of the constricted DA and by supporting luminal remodeling. A retrospective clinical study revealed that thrombocytopenia is an independent predictor for failure of DA closure in preterm human newborns, indicating that platelets are likely to contribute to DA closure in humans.
The etiology and determinants of hospital closure.
Longo, D R; Sohn, M W; Shortell, S M
1996-01-01
This article examines the etiology of hospital closure and the correlates of hospital closure and the extent of similarity in this organizational outcome between pre- and post-Prospective Payment System (PPS) implementation. It also replicates a study from an earlier time period. Findings support the study's main hypotheses: in more stringent and turbulent markets, institutional and strategic variables are more important determinants of hospital closure. Merger acquisitions are found to be similar to both system acquisitions and autonomous hospitals. Standard Metropolitan Statistical Area (SMSA) status and regulation show an effect on hospital closure and merger acquisition. While many similarities exist when compared to the replicated study and findings prior to PPS implementation, it appears that sufficient differences exist to support the hypothesis that the PPS has an impact upon hospital organizational outcome.
Space Station evolution study oxygen loop closure
NASA Technical Reports Server (NTRS)
Wood, M. G.; Delong, D.
1993-01-01
In the current Space Station Freedom (SSF) Permanently Manned Configuration (PMC), physical scars for closing the oxygen loop by the addition of oxygen generation and carbon dioxide reduction hardware are not included. During station restructuring, the capability for oxygen loop closure was deferred to the B-modules. As such, the ability to close the oxygen loop in the U.S. Laboratory module (LAB A) and the Habitation A module (HAB A) is contingent on the presence of the B modules. To base oxygen loop closure of SSF on the funding of the B-modules may not be desirable. Therefore, this study was requested to evaluate the necessary hooks and scars in the A-modules to facilitate closure of the oxygen loop at or subsequent to PMC. The study defines the scars for oxygen loop closure with impacts to cost, weight and volume and assesses the effects of byproduct venting. In addition, the recommended scenarios for closure with regard to topology and packaging are presented.
The Impact of School Closures on Equity of Access in Chicago
ERIC Educational Resources Information Center
Lee, Jin; Lubienski, Christopher
2017-01-01
This study examines the impact of school closures on the sociospatial distribution of equitable access to schooling following the school closure policy pursued by the Chicago Public Schools in 2013. By examining access in terms of proximity between students and schools, the study estimates the changes in accessibility before and after school…
In Situ Aerosol Size Distributions and Clear Column Radiative Closure During ACE-2
NASA Technical Reports Server (NTRS)
Collins, D. R.; Johnson, H. H.; Seinfeld, J. H.; Flagan, R. C.; Gasso, S.; Hegg, D. A.; Russell, P. B.; Schmid, B.; Livingston, J. M.; Oestroem, E.;
2000-01-01
As part of the second Aerosol Characterization Experiment (ACE-2) during June and July of 1997, aerosol size distributions were measured on board the CIRPAS Pelican aircraft through the use of a DMA and two OPCS. During the campaign, the boundary layer aerosol typically possessed characteristics representative of a background marine aerosol or a continentally influenced aerosol, while the free tropospheric aerosol was characterized by the presence or absence of a Saharan dust layer. A range of radiative closure comparisons were made using the data obtained during vertical profiles flown on four missions. Of particular interest here are the comparisons made between the optical properties as determined through the use of measured aerosol size distributions and those measured directly by an airborne 14-wavelength sunphotometer and three nephelometers. Variations in the relative humidity associated with each of the direct measurements required consideration of the hygroscopic properties of the aerosol for size distribution based calculations. Simultaneous comparison with such a wide range of directly measured optical parameters not only offers evidence of the validity of the physicochemical description of the aerosol when closure is achieved, but also provides insight into potential sources of error when some or all of the comparisons result in disagreement. Agreement between the derived and directly measured optical properties varied for different measurements and for different cases. Averaged over the four case studies, the derived extinction coefficient at 525 nm exceeded that measured by the sunphotomoter by 2.5% in the clean boundary later, but underestimated measurements by 13% during pollution events. For measurements within the free troposphere, the mean derived extinction coefficient was 3.3% and 17% less than that measured by the sunphotometer during dusty and nondusty conditions, respectively. Likewise, averaged discrepancies between the derived and measured scattering coefficient were -9.6%, +4.7%, +17%, and -41% for measurements within the clean boundary layer, polluted boundary layer, free troposphere with a dust layer, and free troposphere without a dust layer, respectively. Each of these quantities, as well as the majority of the > 100 individual comparisons from which they were averaged, were within estimated uncertainties.
HWANG, HUI-JEONG; YOON, KYUNG LIM; SOHN, IL SUK
2016-01-01
The present study reported the case of a 60-year-old female with patent ductus arteriosus (PDA) and a bicuspid aortic valve, who presented with transient severe left ventricular (LV) dysfunction following percutaneous closure of PDA, as identified by speckle tracking analysis. Transient LV dysfunction following PDA closure has previously been reported; however, severe LV dysfunction is rare. In the present case, the combination of a large PDA size, large amount of shunting, LV remodeling and bicuspid aortic valve may have induced serious deterioration of LV function following PDA closure. Furthermore, speckle-tracking echocardiography may be useful in the estimation of functional alterations in the myocardium of the LV following PDA closure. The observations detailed in the present study may improve the understanding of the pathophysiology and myocardial patterns of transient left ventricular dysfunction following PDA closure in adult humans. PMID:26998021
Hwang, Hui-Jeong; Yoon, Kyung Lim; Sohn, Il Suk
2016-03-01
The present study reported the case of a 60-year-old female with patent ductus arteriosus (PDA) and a bicuspid aortic valve, who presented with transient severe left ventricular (LV) dysfunction following percutaneous closure of PDA, as identified by speckle tracking analysis. Transient LV dysfunction following PDA closure has previously been reported; however, severe LV dysfunction is rare. In the present case, the combination of a large PDA size, large amount of shunting, LV remodeling and bicuspid aortic valve may have induced serious deterioration of LV function following PDA closure. Furthermore, speckle-tracking echocardiography may be useful in the estimation of functional alterations in the myocardium of the LV following PDA closure. The observations detailed in the present study may improve the understanding of the pathophysiology and myocardial patterns of transient left ventricular dysfunction following PDA closure in adult humans.
Magnetic resonance imaging study of eye congenital birth defects in mouse model
Tucker, Zachary; Mongan, Maureen; Meng, Qinghang; Xia, Ying
2017-01-01
Purpose Embryonic eyelid closure is a well-documented morphogenetic episode in mammalian eye development. Detection of eyelid closure defect in humans is a major challenge because eyelid closure and reopen occur entirely in utero. As a consequence, congenital eye defects that are associated with failure of embryonic eyelid closure remain unknown. To fill the gap, we developed a mouse model of defective eyelid closure. This preliminary work demonstrates that the magnetic resonance imaging (MRI) approach can be used for the detection of extraocular muscle abnormalities in the mouse model. Methods Mice with either normal (Map3k1+/−) or defective (Map3k1−/−) embryonic eyelid closure were used in this study. Images of the extraocular muscles were obtained with a 9.4 T high resolution microimaging MRI system. The extraocular muscles were identified, segmented, and measured in each imaging slice using an in-house program. Results In agreement with histological findings, the imaging data show that mice with defective embryonic eyelid closure develop less extraocular muscle than normal mice. In addition, the size of the eyeballs was noticeably reduced in mice with defective embryonic eyelid closure. Conclusions We demonstrated that MRI can potentially be used for the study of extraocular muscle in the mouse model of the eye open-at-birth defect, despite the lack of specificity of muscle group provided by the current imaging resolution. PMID:28848319
[Factors influencing the prognosis of patent ductus arteriosus in very low birth weight infants].
Wang, Chen-Hong; Shi, Li-Ping; Ma, Xiao-Lu; Luo, Fang; Chen, Zheng; Lin, Hui-Jia; DU, Li-Zhong
2016-08-01
To investigate the factors influencing the prognosis of patent ductus arteriosus (PDA) in very low birth weight (VLBW) infants. A total of 194 VLBW infants who were admitted from January 2012 to December 2014 were enrolled as study subjects. According to cardiac ultrasound findings and treatment outcome, these infants were divided into non-PDA group, spontaneous closure group, pharmaceutical closure group, and surgical closure group. Their clinical and echocardiographic characteristics were analyzed. The spontaneous closure rate of PDA was 58.7%. The spontaneous closure group showed significantly higher gestational age, birth weight, and proportion of small-for-gestational-age infants than the pharmaceutical and surgical closure groups (P<0.05). The pharmaceutical and surgical closure groups had a significantly higher incidence rate of neonatal respiratory distress syndrome and a significantly higher proportion of infants who were given pulmonary surfactant (PS) than the spontaneous closure group (P<0.05). During different periods of time, the spontaneous closure group had a significantly smaller ductus arteriosus diameter than the pharmaceutical and surgical closure groups (P<0.05). The multivariate logistic regression analysis showed that gestational age, application of PS, and ductus arteriosus diameter at 48 hours were significantly associated with the prognosis of PDA. The major transductal flow pattern in the spontaneous closure group was closing pattern, while in the pharmaceutical and surgical closure groups, the main flow patterns were pulmonary hypertension and growing patterns within 48 hours and growing pattern on days 4 and 7. The VLBW infants have a high spontaneous closure rate of PDA. A decreased closure rate of PDA is associated with the lower gestational age and the application of PS. PDA with a large ductus arteriosus diameter and a growing or pulsatile flow pattern cannot easily achieve spontaneous closure.
Chirumbolo, Antonio; Brizi, Ambra; Mastandrea, Stefano; Mannetti, Lucia
2014-01-01
Art preferences are affected by a number of subjective factors. This paper reports two studies which investigated whether need for closure shapes implicit art preferences. It was predicted that higher need for closure would negatively affect implicit preferences for abstract art. In study one, 60 participants were tested for dispositional need for closure and then completed an Implicit Association Test (IAT) task to measure their implicit preference for abstract (vs. figurative) paintings. In study two, 54 participants completed the same IAT task. In this experiment need for closure was both manipulated by cognitive load and tapped as a dispositional trait. Results of the studies converged in showing that after controlling for other important individual factors such as participants'expertise and cognitive ability, need for closure, both as a dispositional trait and as a situationally induced motivational state, was negatively associated with implicit preference for abstract art. PMID:25360697
Chirumbolo, Antonio; Brizi, Ambra; Mastandrea, Stefano; Mannetti, Lucia
2014-01-01
Art preferences are affected by a number of subjective factors. This paper reports two studies which investigated whether need for closure shapes implicit art preferences. It was predicted that higher need for closure would negatively affect implicit preferences for abstract art. In study one, 60 participants were tested for dispositional need for closure and then completed an Implicit Association Test (IAT) task to measure their implicit preference for abstract (vs. figurative) paintings. In study two, 54 participants completed the same IAT task. In this experiment need for closure was both manipulated by cognitive load and tapped as a dispositional trait. Results of the studies converged in showing that after controlling for other important individual factors such as participants'expertise and cognitive ability, need for closure, both as a dispositional trait and as a situationally induced motivational state, was negatively associated with implicit preference for abstract art.
Multidisciplinary management of patent foramen ovale (PFO) and cryptogenic stroke/TIA
Mirzada, Naqibullah; Ladenvall, Per; Hansson, Per-Olof; Eriksson, Peter; Dellborg, Mikael
2013-01-01
Purpose Patent foramen ovale (PFO) has been implicated as a risk factor for cryptogenic ischemic stroke (CS). However, there is still a lack of widely accepted, undisputed indications for PFO closure. The present study describes the concept of the multidisciplinary PFO conference and a decision making process for closure versus no closure that was developed into a formalized clinical algorithm, and presents the results of implementing these, in terms of number and proportion of PFO closures as well as repeat referrals. Design Five specialists in neurology, cardiology, internal medicine, thromboembolism, and echocardiography evaluated the clinical data of 311 patients at PFO conferences during 2006 to 2009. The main criteria for closure were patients with first-ever CS with PFO and atrial septal aneurysm, or patients with recurrent CS and PFO without atrial septal aneurysm. Results A total of 143 patients (46%) were accepted for closure and 167 patients were rejected. Patients accepted for closure were younger (mean 50 years versus 58 years) (P < 0.001). The acceptance rate for PFO closure was similar throughout these years, with an average of 45%. Three of 167 patients (1.8%) initially rejected for PFO closure were re-referred due to recurrent stroke, and the PFO closure was subsequently performed. Conclusion The acceptance rate of less than 50% in the present study underscores the complex relationship between CS and PFO. Whatever the criteria used for PFO closure, any unit caring for these patients needs to have a rigorous process to avoid overtreatment as well as undertreatment and to ensure that personal preferences and economic incentives do not steer the selection process. Our algorithm provides a stable acceptance rate and a low rate of repeat referrals. PMID:24082787
Modeling and Simulating Passenger Behavior for a Station Closure in a Rail Transit Network
Yin, Haodong; Han, Baoming; Li, Dewei; Wu, Jianjun; Sun, Huijun
2016-01-01
A station closure is an abnormal operational situation in which the entrances or exits of a rail transit station have to be closed for some time due to an unexpected incident. A novel approach is developed to estimate the impacts of the alternative station closure scenarios on both passenger behavioral choices at the individual level and passenger demand at the disaggregate level in a rail transit network. Therefore, the contributions of this study are two-fold: (1) A basic passenger behavior optimization model is mathematically constructed based on 0–1 integer programming to describe passengers’ responses to alternative origin station closure scenarios and destination station closure scenarios; this model also considers the availability of multi-mode transportation and the uncertain duration of the station closure; (2) An integrated solution algorithm based on the passenger simulation is developed to solve the proposed model and to estimate the effects of a station closure on passenger demand in a rail transit network. Furthermore, 13 groups of numerical experiments based on the Beijing rail transit network are performed as case studies with 2,074,267 records of smart card data. The comparisons of the model outputs and the manual survey show that the accuracy of our proposed behavior optimization model is approximately 80%. The results also show that our model can be used to capture the passenger behavior and to quantitatively estimate the effects of alternative closure scenarios on passenger flow demand for the rail transit network. Moreover, the closure duration and its overestimation greatly influence the individual behavioral choices of the affected passengers and the passenger demand. Furthermore, if the rail transit operator can more accurately estimate the closure duration (namely, as g approaches 1), the impact of the closure can be somewhat mitigated. PMID:27935963
Modeling and Simulating Passenger Behavior for a Station Closure in a Rail Transit Network.
Yin, Haodong; Han, Baoming; Li, Dewei; Wu, Jianjun; Sun, Huijun
2016-01-01
A station closure is an abnormal operational situation in which the entrances or exits of a rail transit station have to be closed for some time due to an unexpected incident. A novel approach is developed to estimate the impacts of the alternative station closure scenarios on both passenger behavioral choices at the individual level and passenger demand at the disaggregate level in a rail transit network. Therefore, the contributions of this study are two-fold: (1) A basic passenger behavior optimization model is mathematically constructed based on 0-1 integer programming to describe passengers' responses to alternative origin station closure scenarios and destination station closure scenarios; this model also considers the availability of multi-mode transportation and the uncertain duration of the station closure; (2) An integrated solution algorithm based on the passenger simulation is developed to solve the proposed model and to estimate the effects of a station closure on passenger demand in a rail transit network. Furthermore, 13 groups of numerical experiments based on the Beijing rail transit network are performed as case studies with 2,074,267 records of smart card data. The comparisons of the model outputs and the manual survey show that the accuracy of our proposed behavior optimization model is approximately 80%. The results also show that our model can be used to capture the passenger behavior and to quantitatively estimate the effects of alternative closure scenarios on passenger flow demand for the rail transit network. Moreover, the closure duration and its overestimation greatly influence the individual behavioral choices of the affected passengers and the passenger demand. Furthermore, if the rail transit operator can more accurately estimate the closure duration (namely, as g approaches 1), the impact of the closure can be somewhat mitigated.
Cost comparison of transcatheter and operative closures of ostium secundum atrial septal defects
O’Byrne, Michael L.; Gillespie, Matthew J.; Shinohara, Russell T.; Dori, Yoav; Rome, Jonathan J.; Glatz, Andrew C.
2015-01-01
Background Clinical outcomes for transcatheter and operative closures of atrial septal defects (ASDs) are similar. Economic cost for each method has not been well described. Methods A single-center retrospective cohort study of children and adults <30 years of age undergoing closure for single secundum ASD from January 1, 2007, to April 1, 2012, was performed to measure differences in inflation-adjusted cost of operative and transcatheter closures of ASD. A propensity score weight-adjusted multivariate regression model was used in an intention-to-treat analysis. Costs for reintervention and crossover admissions were included in primary analysis. Results A total of 244 subjects were included in the study (64% transcatheter and 36% operative), of which 2% (n = 5) were ≥18 years. Crossover rate from transcatheter to operative group was 3%. Risk of reintervention (P = .66) and 30-day mortality (P = .37) were not significantly different. In a multivariate model, adjusted cost of operative closure was 2012 US $60,992 versus 2012 US $55,841 for transcatheter closure (P < .001). Components of total cost favoring transcatheter closure were length of stay, medications, and follow-up radiologic and laboratory testing, overcoming higher costs of procedure and echocardiography. Professional costs did not differ. The rate of 30-day readmission was greater in the operative cohort, further increasing the cost advantage of transcatheter closure. Sensitivity analyses demonstrated that costs of follow-up visits influenced relative cost but that device closure remained favorable over a broad range of crossover and reintervention rates. Conclusion For single secundum ASD, cost comparison analysis favors transcatheter closure over the short term. The cost of follow-up regimens influences the cost advantage of transcatheter closure. PMID:25965721
Preliminary results of laser tissue welding in extravesical reimplantation of the ureters.
Kirsch, A J; Dean, G E; Oz, M C; Libutti, S K; Treat, M R; Nowygrod, R; Hensle, T W
1994-02-01
One exciting potential use of laparoscopic technology is the extravesical reimplantation of the ureters. We have assessed the efficacy of laser-activated fibrinogen solder to close vesical muscle flaps over submucosal ureters (Lich-Gregoir technique) in a canine model. Four dogs were subjected to unilateral flap closures via a protein solder (indocyanine green and fibrinogen) applied to the bladder serosa and exposed to 808 nm. continuous wave diode laser energy. Contralateral reimplantation was performed using 4-zero vicryl muscle flap closures (controls). At 7, 14 and 28 days postoperatively, intravenous pyelograms confirmed bilateral ureteral patency. At intravesical pressures above 100 cm. H2O, there was no evidence of wound disruption in either group. Nondisrupted wound closures were sectioned and strained until ultimate breakage to determine tensile strength. At each study interval the laser-welded closures withstood greater stress than the controls. Although these data represent single tissue samples and are not amenable to statistical analysis, laser-welded closures appeared to be stronger at each study interval. In conclusion, laser-welded vesical wound closures appear at least as strong as suture closures in the canine model.
A novel one-shot circular stapler closure for atrial septal defect in a beating-heart porcine model.
Tarui, Tatsuya; Tomita, Shigeyuki; Ishikawa, Norihiko; Ohtake, Hiroshi; Watanabe, Go
2015-02-01
In surgical atrial septal defect (ASD) closure, there are no techniques or devices that can close the ASD accurately in a short time under a beating heart. We have developed a simple and automatic ASD closure technique using a circular stapler. This study assessed the feasibility and efficacy of a new circular stapler closure for ASD. Under a continuous beating heart, hand-sewn patch plasty ASD closure was performed in 6 pigs (group A) and circular stapler ASD closure was performed in 6 pigs (group B). The time to close the ASD and the effectiveness of the closure were compared. Closure was significantly faster in group B (10.5 ± 1.0 seconds) than in group A (664 ± 10 seconds; p < 0.05). There was no leakage at the closure site, and sufficient tolerance was confirmed. A circular stapler can be used to treat ASD faster than hand-sewn patch plasty, with sufficient pressure tolerance in a beating heart porcine model. Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.
Ahmadi, Alireza; Sabri, Mohammadreza; Bigdelian, Hamid; Dehghan, Bahar; Gharipour, Mojgan
2014-01-01
Various devices have been recently employed for percutaneous closure of the patent ductus arteriosus (PDA). Although the high effectiveness of device closure techniques has been clearly determined, a few studies have focused on the cost-effectiveness and also postoperative complications of these procedures in comparison with open surgery. The present study aimed to evaluate the clinical outcome and cost-effectiveness of PDA occlusion by Amplatzer and coil device in comparisong with open surgery. In this cross-sectional study, a randomized sample of 201 patients aged 1 month to 16 years (105 patients with device closure and 96 patients with surgical closure) was selected. The ratio of total pulmonary blood flow to total systemic blood flow, the Qp/Qs ratio, was measured using a pulmonary artery catheter. The cost analysis included direct medical care costs associated with device implantation and open surgery, as well as professional fees. All costs were calculated in Iranian Rials and then converted to US dollars. There was no statistical difference in mean Qp/Qs ratio before the procedure between the device closure group and the open surgery group (2.1 ± 0.7 versus 1.7 ± 0.6, P = 0.090). The mean measured costs were overall higher in the device closure group than in open closure group (948.87 ± 548.76 US$ versus 743.70 ± 696.91 US$, P < 0.001). This difference remained significant after adjustment for age and gender (Standardized Beta = 0.160, P = 0.031). PDA closure with the Amplatzer ductal occluder (1053.05 ± 525.73 US$) or with Nit-Occlud coils (PFM) (912.73 ± 565.94 US$, P < 0.001) was more expensive than that via open surgery. However, the Cook detachable spring coils device closure (605.65 ± 194.62 US$, P = 0.650) had a non-significant cost difference with open surgery. No event was observed in the device closure group regarding in-hospital mortality or morbidity; however, in another group, 2 in-hospital deaths occurred, two patients experienced pneumonia and seizure, and one suffered electrolyte abnormalities including hyponatremia and hypocalcemia. Although open surgery seems to be less expensive than device closure technique, because of lower mortality and morbidity, the latter group is more preferable.
Comparison of two spectral domain optical coherence tomography devices for angle-closure assessment.
Quek, Desmond T; Narayanaswamy, Arun K; Tun, Tin A; Htoon, Hla M; Baskaran, Mani; Perera, Shamira A; Aung, Tin
2012-08-03
To compare two spectral domain optical coherence tomography (SD-OCT) devices for the identification of angle structures and the presence of angle closure. This was a prospective comparative study. Consecutive patients underwent gonioscopy and anterior segment imaging using two SD-OCT devices (iVue and Cirrus). Images were evaluated for the ability to detect angle structures such as Schwalbe's line (SL), trabecular meshwork (TM), Schlemm's canal (SC), and scleral spur (SS), and the presence of angle closure. Angle closure was defined as iris contact with the angle wall anterior to the SS on SD-OCT, and nonvisibility of the posterior TM on gonioscopy. Angle closure in an eye was defined as ≥two quadrants of closed angles. AC1 statistic was used to assess the agreement between devices. Of the 69 subjects studied (46.4% male, 84.1% Chinese, mean age 64.0 ± 10.5 years), 40 subjects (40 eyes, 58.0%) had angle closure on gonioscopy. The most identifiable structure on Cirrus SD-OCT was the SS (82.2%) and SL on iVue SD-OCT (74.5%). Angle closure was indeterminable in 14.5% and 50.7% of Cirrus and iVue scans (P < 0.001), respectively. Interdevice agreement for angle closure was moderately strong (AC1 = 0.67), but agreement with gonioscopy was only fair (AC1 = 0.35 and 0.50 for Cirrus and iVue, respectively). It was more difficult to determine angle closure status with iVue compared with Cirrus SD-OCT. There was fair agreement between both devices with gonioscopy for identifying angle closure.
Yamamoto, Takayuki; Umegae, Satoru; Kitagawa, Tatsushi; Matsumoto, Koichi
2005-10-01
The etiology of pouch inflammation after restorative proctocolectomy is unknown. The fecal stream and immunological reactions are potential pathological factors. This study was performed to examine the impact of the fecal stream and stasis on immunological reactions in the pouch. Patients who underwent a restorative proctocolectomy with a covering ileostomy for ulcerative colitis were studied. Mucosal biopsy specimens were obtained from both the pouch and the proximal ileum at the time of ileostomy closure, and 3, 6, and 12 months after ileostomy closure. As a control group, normal ileal biopsies were obtained from patients with colonic polyps. At the time of ileostomy closure, mucosal interleukin-1beta, interleukin-6, interleukin-8, and tumor necrosis factor-alpha levels in the pouch and the proximal ileum were not significantly different from those in the normal control group. At 3 months after ileostomy closure, the mucosal cytokine levels in the pouch increased significantly compared with those at ileostomy closure, and their levels were significantly higher than those in the proximal ileum. At 6 and 12 months after ileostomy closure, the mucosal cytokine levels in the pouch did not change significantly compared with those at 3 months after ileostomy closure. The mucosal cytokine levels in the proximal ileum did not change significantly during the entire study. The immunological reactions in the pouch occurred soon after ileostomy closure, and continued for at least 1 yr. The fecal stream and stasis play an important part in the pathogenesis of immunological reactions in the ileal pouch.
O'Byrne, Michael L; Kennedy, Kevin F; Rome, Jonathan J; Glatz, Andrew C
2018-02-01
Practice variation is a potentially important measure of healthcare quality. The IMPACT registry provides a representative national sample with which to study practice variation in trans-catheter interventions for congenital heart disease. We studied cases for closure of atrial septal defect (ASD) and patent ductus arteriosus (PDA) in IMPACT between January 1, 2011, and September 30, 2015, using hierarchical multivariate models studying (1) the distribution of indications for closure and (2) in patients whose indication for closure was left (LVVO) or right ventricular volume overload (RVVO), the factors influencing probability of closure of a small defect (either in size or in terms of the magnitude of shunt). Over the study period, 5233 PDA and 4459 ASD cases were performed at 77 hospitals. The indications for ASD closure were RVVO in 84% and stroke prevention in 13%. Indications for PDA closure were LVVO in 57%, endocarditis prevention in 36%, and pulmonary hypertension in 7%. There was statistically significant variability in indications between hospitals for PDA and ASD procedures (median rate ratio (MRR): 1.3 and 1.1; both P<.001). The proportion of cases for volume overload with a Qp:Qs <1.5:1 decreased with increasing PDA and ASD procedural volume (P=.04 and 0.05). For ASD, the proportion was higher at hospitals with a larger proportion of adult cases (P=.0007). There was significant variation in practice in the risk of closing PDA <2 mm for LVVO (MRR: 1.4, P<.001). There is measurable variation in transcatheter closure of PDA and ASD. Further research is necessary to study whether this affects outcomes or resource utilization. Copyright © 2017 Elsevier Inc. All rights reserved.
Ates, Ufuk; Ergun, Ergun; Gollu, Gulnur; Sozduyar, Sumeyye; Kologlu, Meltem; Cakmak, Murat; Dindar, Huseyin; Yagmurlu, Aydin
2018-03-01
Pilonidal sinus (PS) is an infectious and inflammatory disease of sacrococcygeal region. Current methods include; surgical excision with/without suturing the defect, rhomboid excision and flap and chemical substance application. In this study, crystallized phenol application was compared to excision and primary closure. This retrospective study included pediatric patients with PS who were treated with excision and primer closure technique and phenol application. The patients' medical data were analyzed retrospectively. This study included 117 patients with PS. There were 52 girls (44%) and 65 boys (56%). Mean age of children was 15.6 (12-20) years. Excision and primary closure were applied to 77 patients (66%) and phenol was applied to 40 patients (34%). The children in phenol group were discharged on the operation day; mean hospitalization time in the excision and primary closure group was 2.7 (1-14) days. Mean follow up was 44.6 (8-82) months for primary excision and closure group and 8.1 (1-19) months for phenol group. Although many surgical and non-surgical treatment modalities have been described for PS, the optimal one remains unknown. Limited with the retrospective nature of the data, crystallized phenol application seems a feasible minimal invasive alternative to primary closure of PS with lower recurrence and complication rates in children. Level III. Copyright © 2017 Elsevier Inc. All rights reserved.
PFO and Migraine: Is There a Role for Closure?
Rayhill, Melissa; Burch, Rebecca
2017-03-01
Observational studies suggest that closure of a patent foramen ovale for other indications may reduce or even eliminate migraine attacks, particularly migraine with aura. The first randomized clinical trial of patent foramen ovale (PFO) closure for prevention of migraine, the MIST trial, showed negative results. The results of the other two completed studies in this area have recently been published in the last year. PRIMA and PREMIUM were also both negative for their primary endpoints. The PREMIUM trial did show a reduction in headache days in the migraine with aura subgroup but the final results of this subset analysis have not been published. There may be an as yet undetermined subgroup of patients with migraine who would benefit from closure, but slow recruitment has been a barrier to further study. Several potentially life-threatening procedure-related adverse events occurred in the clinical trials. At this time, we recommend against offering PFO closure as a preventive treatment for migraine. Based on available observational data, patients for whom PFO closure is indicated for other reasons may see some improvement in their migraines.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Griffin, Brian M.; Larson, Vincent E.
Microphysical processes, such as the formation, growth, and evaporation of precipitation, interact with variability and covariances (e.g., fluxes) in moisture and heat content. For instance, evaporation of rain may produce cold pools, which in turn may trigger fresh convection and precipitation. These effects are usually omitted or else crudely parameterized at subgrid scales in weather and climate models.A more formal approach is pursued here, based on predictive, horizontally averaged equations for the variances, covariances, and fluxes of moisture and heat content. These higher-order moment equations contain microphysical source terms. The microphysics terms can be integrated analytically, given a suitably simplemore » warm-rain microphysics scheme and an approximate assumption about the multivariate distribution of cloud-related and precipitation-related variables. Performing the integrations provides exact expressions within an idealized context.A large-eddy simulation (LES) of a shallow precipitating cumulus case is performed here, and it indicates that the microphysical effects on (co)variances and fluxes can be large. In some budgets and altitude ranges, they are dominant terms. The analytic expressions for the integrals are implemented in a single-column, higher-order closure model. Interactive single-column simulations agree qualitatively with the LES. The analytic integrations form a parameterization of microphysical effects in their own right, and they also serve as benchmark solutions that can be compared to non-analytic integration methods.« less
ERIC Educational Resources Information Center
Cleveland, H. Harrington; Crosnoe, Robert
2004-01-01
Intergenerational closure refers to parents' knowing the parents of their adolescents' friends. This study treated intergenerational closure - as reported by the parents of adolescent twins - as the dependent variable in a behavioral genetic analysis. The sample consisted of identical and fraternal twin pairs in the National Longitudinal Study of…
A clinical study of space closure with nickel-titanium closed coil springs and an elastic module.
Samuels, R H; Rudge, S J; Mair, L H
1998-07-01
A previous study has shown that a 150-gram nickel-titanium closed coil spring (Sentalloy, GAC International Inc.) closed spaces more quickly and more consistently than an elastic module (Alastik, Unitec/3M). This study used the same friction sensitive sliding mechanics of pitting the six anterior teeth against the second bicuspid and first molars, to examine the rate of space closure of 100-gram and 200-gram nickel-titanium closed coil springs. The results for the three springs and elastic module were compared. The nickel-titanium closed coil springs produced a more consistent space closure than the elastic module. The 150- and 200-gram springs produced a faster rate of space closure than the elastic module or the 100-gram spring. No significant difference was noted between the rates of closure for the 150- and the 200-gram springs.
Jin, Xiao-Fang; Ye, Zhong-Ming; Amboka, Grace M; Wang, Qing-Feng; Yang, Chun-Feng
2017-01-01
A sensitive bilobed stigma is thought to assure reproduction, avoid selfing and promote outcrossing. In addition, it may also play a role in pollinator selection since only pollinators with the appropriate body size can trigger this mechanism. However, no experimental study has investigated how the sensitive stigma responds to different pollinators and its potential effects on pollination. Mazus miquelii (Phrymaceae), a plant with a bilobed stigma was studied to investigate the relationship between stigma behaviors and its multiple insect pollinators. The reaction time of stigma closure after touched, duration of temporary closure, and factors determining permanent closure of the stigma were studied when flowers were exposed to different visitors and conducted with hand pollination. Manual stimulation was also used to detect the potential differences in stigmas when touched with different degrees of external forces. Results indicated that, compared to pollinators with a small body size, larger pollinators transferred more pollen grains to the stigma, causing a rapid stigma response and resulting in a higher percentage of permanent closures. Duration of temporary closure was negatively correlated with the speed of stigma closure; a stigma that closed more rapidly reopened more slowly. Manual stimulation showed that reaction time of stigma closure was likely a response to external mechanical forces. Hand pollination treatments revealed that the permanent closure of a stigma was determined by the size of stigmatic pollen load. For large pollinators, the speedy reaction of the stigma might help to reduce pollen loss, enhance pollen germination and avoid obstructing pollen export. Stigmas showed low sensitivity when touched by inferior pollinators, which may have increased the possibility of pollen deposition by subsequent visits. Therefore, the stigma behavior in M. miquelii is likely a mechanism of pollinator selection to maximize pollination success.
NASA Technical Reports Server (NTRS)
Livingston, John M.; Kapustin, Vladimir N.; Schmid, Beat; Russell, Philip B.; Quinn, Patricia K.; Bates, Timothy S.; Durkee, Philip A.; Smith, Peter J.; Freudenthaler, Volker; Wiegner, Matthias
2000-01-01
Analyses of aerosol optical depth (AOD) and columnar water vapor (CWV) measurements acquired with NASA Ames Research Center's six-channel Airborne Tracking Sunphotometer (AATS-6) operated aboard the R/V (research vehicle) Professor Vodyanitskiy during the second Aerosol Characterization Experiment (ACE-2) are discussed. Data are compared with various in situ and remote measurements for selected cases. The focus is on 10 July, when the Pelican airplane flew within 70 km of the ship near the time of a NOAA (National Oceanographic and Atmospheric Administration)-14/AVHRR (Advanced Very High Resolution Radiometer) satellite overpass and AOD measurements with the 14-channel Ames Airborne Tracking Sunphotometer (AATS-14) above the marine boundary layer (MBL) permitted calculation of AOD within the MBL from the AATS-6 measurements. A detailed column closure test is performed for MBL AOD on 10 July by comparing the AATS-6 MBL AODs with corresponding values calculated by combining shipboard particle size distribution measurements with models of hygroscopic growth and radiosonde humidity profiles (plus assumptions on the vertical profile of the dry particle size distribution and composition). Large differences (30-80% in the mid-visible) between measured and reconstructed AODs are obtained, in large part because of the high sensitivity of the closure methodology to hygroscopic growth models, which vary considerably and have not been validated over the necessary range of particle size/composition distributions. The wavelength dependence of AATS-6 AODs is compared with the corresponding dependence of aerosol extinction calculated from shipboard measurements of aerosol size distribution and of total scattering measured by a shipboard integrating nephelometer for several days. Results are highly variable, illustrating further the great difficulty of deriving column values from point measurements. AATS-6 CWV values are shown to agree well with corresponding values derived from radiosonde measurements during eight soundings on seven days and also with values calculated from measurements taken on 10 July with the AATS-14 and the University of Washington Passive Humidigraph aboard the Pelican.
Assessment of a simple, novel endoluminal method for gastrotomy closure in NOTES.
Lee, Sang Soo; Oelschlager, Brant K; Wright, Andrew S; Soares, Renato V; Sinan, Huseyin; Montenovo, Martin I; Hwang, Joo Ha
2011-10-01
A reliable method for gastrotomy closure in NOTES will be essential for NOTES to become viable clinically. However, methods using existing and widely available endoscopic accessories have been ineffective. The objective of this study was to evaluate the feasibility and safety of a new simple method for gastric closure (retracted clip-assisted loop closure) that uses existing endoscopic accessories with minor modifications. The retracted clip-assisted loop closure technique involves deploying 3-4 Resolution(®) clips (modified by attaching a 90-cm length of suture to the end of each clip) along the margin of the gastrotomy with one jaw on the serosal surface and the other jaw on the mucosal surface. The suture strings are threaded through an endoloop. Traction is then applied to the strings causing the gastric wall to tent. The endoloop is secured below the tip of the clips, completing a full-thickness gastrotomy closure. The main outcome measures were feasibility, efficacy, and safety of the new retracted clip-assisted loop closure technique for NOTES gastrotomy closure. An air-tight seal was achieved in 100% (n = 9) of stomachs. The mean leak pressure was 116.3 (±19.4) mmHg. The retracted clip-assisted loop closure technique can be used to perform NOTES gastrotomy closure by using existing endoscopic accessories with minor modifications.
Amokrane, S; Ayadim, A; Malherbe, J G
2005-11-01
A simple modification of the reference hypernetted chain (RHNC) closure of the multicomponent Ornstein-Zernike equations with bridge functions taken from Rosenfeld's hard-sphere bridge functional is proposed. Its main effect is to remedy the major limitation of the RHNC closure in the case of highly asymmetric mixtures--the wide domain of packing fractions in which it has no solution. The modified closure is also much faster, while being of similar complexity. This is achieved with a limited loss of accuracy, mainly for the contact value of the big sphere correlation functions. Comparison with simulation shows that inside the RHNC no-solution domain, it provides a good description of the structure, while being clearly superior to all the other closures used so far to study highly asymmetric mixtures. The generic nature of this closure and its good accuracy combined with a reduced no-solution domain open up the possibility to study the phase diagram of complex fluids beyond the hard-sphere model.
Amoogzar, Hamid; Shakiba, Ali Mohammad; Derakhshan, Dorna; Ajami, Gholamhossein; Cheriki, Sirous; Borzouee, Mohammad; Edraki, Mohammad Reza; Mehdizadegan, Nima
2015-01-01
The aim of this study was to evaluate the left ventricular systolic and diastolic function before and after transcatheter percutaneous patent ductus arteriosus (PDA) closure. 21 children (age >6 months old) diagnosed with hemodynamically significant PDA underwent percutaneous PDA closure. Conventional, Doppler and tissue Doppler imaging and speckled-derived strain rate echocardiography were done at pre-closure, 1 day (early) and 1 month (late) post-closure. Mean age of the patients (female/male: 1.3) was 17.54 ± 24.7 months with the mean PDA diameter of 3.6 ± 0.8 mm. Systolic measures (ejection fraction, shortening fraction) reduced significantly early after PDA closure (P < 0.05). After 1 month, both improved significantly; ultimately, after 1 month no change was observed in systolic function measures compared with the pre-closure status. Early and late diastolic flow velocities of mitral (E M and A M) reduced considerably in early and late post-closure time (P < 0.05). Both early tissue Doppler early velocity of lateral mitral annulus (E'M) and early to late velocity ratio (E'M/A'M) of lateral mitral annulus decreased significantly (P = 0.02) in early post-closure. After 1 month, E'M increased considerably. (P = 0.01) but E'M/A'M had an insignificant rise (P > 0.05). E M/E'M ratio did not change in early post-closure but it had a considerable reduction in the subsequent month compared with the pre- and early post-closure (P < 0.001 for both occasions). Global and segmental longitudinal strain measures reduced significantly early after PDA closure (P < 0.05) but it improved remarkably in the subsequent month. Transcatheter PDA closure causes a significant decrease in left ventricular performance early after PDA closure which recovers completely within 1 month. Also PDA size can affect post-closure left ventricular function.
NASA Astrophysics Data System (ADS)
Yang, Ben; Zhou, Yang; Zhang, Yaocun; Huang, Anning; Qian, Yun; Zhang, Lujun
2018-03-01
Closure assumption in convection parameterization is critical for reasonably modeling the precipitation diurnal variation in climate models. This study evaluates the precipitation diurnal cycles over East Asia during the summer of 2008 simulated with three convective available potential energy (CAPE) based closure assumptions, i.e. CAPE-relaxing (CR), quasi-equilibrium (QE), and free-troposphere QE (FTQE) and investigates the impacts of planetary boundary layer (PBL) mixing, advection, and radiation on the simulation by using the weather research and forecasting model. The sensitivity of precipitation diurnal cycle to PBL vertical resolution is also examined. Results show that the precipitation diurnal cycles simulated with different closures all exhibit large biases over land and the simulation with FTQE closure agrees best with observation. In the simulation with QE closure, the intensified PBL mixing after sunrise is responsible for the late-morning peak of convective precipitation, while in the simulation with FTQE closure, convective precipitation is mainly controlled by advection cooling. The relative contributions of different processes to precipitation formation are functions of rainfall intensity. In the simulation with CR closure, the dynamical equilibrium in the free troposphere still can be reached, implying the complex cause-effect relationship between atmospheric motion and convection. For simulations in which total CAPE is consumed for the closures, daytime precipitation decreases with increased PBL resolution because thinner model layer produces lower convection starting layer, leading to stronger downdraft cooling and CAPE consumption. The sensitivity of the diurnal peak time of precipitation to closure assumption can also be modulated by changes in PBL vertical resolution. The results of this study help us better understand the impacts of various processes on the precipitation diurnal cycle simulation.
Taniguchi, Yuji; Nakamura, Hiroshige; Miwa, Ken; Adachi, Yoshin; Fujioka, Shinji; Haruki, Tomohiro; Horie, Yasushi
2009-07-01
Some reports have described pleural lavage cytology (PLC) to be a prognostic factor for non-small cell lung cancer (NSCLC) patients. However, there have only been a few reports describing the findings both immediately after thoracotomy (PLC after thoracotomy) and before the closure of the chest (PLC before closure). From April 2002 to April 2008, both PLC after thoracotomy and PLC before closure were performed in 296 consecutive patients who underwent resections for NSCLC. PLC after thoracotomy was positive in 14 patients. The survival rate in the PLC after thoracotomy positive cases was significantly poorer than in PLC after thoracotomy negative cases (P=0.047). In contrast, there were 26 PLC before closure positive cases. The survival rate in the PLC before closure positive cases was significantly poorer than in the PLC before closure negative cases (P<0.0001). Multivariate analyses revealed that PLC after thoracotomy is not an independent prognostic factor in our study. However, PLC before closure was an independent prognostic factor based on multivariate analyses. We conclude that PLC before closure was found to be a better prognostic factor than PLC after thoracotomy for NSCLC patients.
Improvement of tricuspid regurgitation after transcatheter ASD closure in older patients.
Chen, L; Shen, J; Shan, X; Wang, F; Kan, T; Tang, X; Zhao, X; Qin, Y
2017-07-19
Adult patients with undiagnosed atrial septal defect (ASD) may have right heart cavity enlargement and functional tricuspid valve insufficiency. Moderate or more severe tricuspid regurgitation has been associated with a worse prognosis, and more serious complications are typically seen in older patients. This study aimed to evaluate the improvement in functional tricuspid regurgitation and heart geometry after transcatheter ASD closure in older patients. The data of 111 patients over 60 years of age with moderate or severe tricuspid regurgitation before ASD closure were analyzed. At the 1‑month and 6‑month follow-up after closure, both tricuspid regurgitation jet area and right atrial volume decreased significantly. Right ventricular volume decreased 1 month after closure, showing a further decrease at the end of the 6‑month follow-up. However, 24 patients (21.6%) still had persistent severe tricuspid regurgitation after the procedure. Multivariate analysis revealed that patient age at ASD closure and pulmonary artery systolic pressure determined by echocardiography before closure were predictors of persistent tricuspid regurgitation after closure. Transcatheter ASD closure in older patients could significantly decrease tricuspid regurgitation and improve right heart geometry.
ASD Closure in Structural Heart Disease.
Wiktor, Dominik M; Carroll, John D
2018-04-17
While the safety and efficacy of percutaneous ASD closure has been established, new data have recently emerged regarding the negative impact of residual iatrogenic ASD (iASD) following left heart structural interventions. Additionally, new devices with potential advantages have recently been studied. We will review here the potential indications for closure of iASD along with new generation closure devices and potential late complications requiring long-term follow-up. With the expansion of left-heart structural interventions and large-bore transseptal access, there has been growing experience gained with management of residual iASD. Some recently published reports have implicated residual iASD after these procedures as a potential source of diminished clinical outcomes and mortality. Additionally, recent trials investigating new generation closure devices as well as expanding knowledge regarding late complications of percutaneous ASD closure have been published. While percutaneous ASD closure is no longer a novel approach to managing septal defects, there are several contemporary issues related to residual iASD following large-bore transseptal access and new generation devices which serve as an impetus for this review. Ongoing attention to potential late complications and decreasing their incidence with ongoing study is clearly needed.
[Velopharyngeal closure pattern and speech performance among submucous cleft palate patients].
Heng, Yin; Chunli, Guo; Bing, Shi; Yang, Li; Jingtao, Li
2017-06-01
To characterize the velopharyngeal closure patterns and speech performance among submucous cleft palate patients. Patients with submucous cleft palate visiting the Department of Cleft Lip and Palate Surgery, West China Hospital of Stomatology, Sichuan University between 2008 and 2016 were reviewed. Outcomes of subjective speech evaluation including velopharyngeal function, consonant articulation, and objective nasopharyngeal endoscopy including the mobility of soft palate, pharyngeal walls were retrospectively analyzed. A total of 353 cases were retrieved in this study, among which 138 (39.09%) demonstrated velopharyngeal competence, 176 (49.86%) velopharyngeal incompetence, and 39 (11.05%) marginal velopharyngeal incompetence. A total of 268 cases were subjected to nasopharyngeal endoscopy examination, where 167 (62.31%) demonstrated circular closure pattern, 89 (33.21%) coronal pattern, and 12 (4.48%) sagittal pattern. Passavant's ridge existed in 45.51% (76/167) patients with circular closure and 13.48% (12/89) patients with coronal closure. Among the 353 patients included in this study, 137 (38.81%) presented normal articulation, 124 (35.13%) consonant elimination, 51 (14.45%) compensatory articulation, 36 (10.20%) consonant weakening, 25 (7.08%) consonant replacement, and 36 (10.20%) multiple articulation errors. Circular closure was the most prevalent velopharyngeal closure pattern among patients with submucous cleft palate, and high-pressure consonant deletion was the most common articulation abnormality. Articulation error occurred more frequently among patients with a low velopharyngeal closure rate.
Rengifo-Moreno, Pablo; Palacios, Igor F; Junpaparp, Parichart; Witzke, Christian F; Morris, D Lynn; Romero-Corral, Abel
2013-11-01
In patients with cryptogenic stroke, transcatheter (TC) closure of a patent foramen ovale (PFO) has not been shown to better prevent recurrent vascular events than medical therapy. However, randomized controlled trials (RCT) to date have included few vascular events, and lack of power has been raised as an important concern. To conduct a systematic review and meta-analysis of existing RCT published studies assessing the recurrence of vascular events after TC PFO closure when compared to medical therapy. Using the search terms "patent foramen ovale", "PFO", "stroke", "percutaneous closure" and "transcatheter closure", Medline, Pubmed, Embase, and Cochrane databases were reviewed from inception through April 2013, with no language restrictions. Only studies in adult humans were considered. Additional references were obtained from the bibliographies of studies reviewed. The following criteria were used for study selection: 1) randomized controlled trial, 2) subjects were adult patients with cryptogenic stroke who were randomized to TC PFO closure or medical treatment (antiplatelet therapy and/or anticoagulation), and 3) reported outcomes included cardiac death, all death, stroke, transient ischemic attack, and peripheral embolism. Methodological and descriptive data, adverse events (including raw data and risk estimates), as well as procedural success and complications were abstracted in duplicate from each study independently, and agreement was tested. We followed rigorously the recommended guidelines for reporting and conducting and assessing quality of meta-analysis of RCT. The primary endpoints pre-specified in advance were recurrent vascular events, and composite endpoint of death, and recurrent vascular events. Three studies were identified as meeting selection criteria. These included a total of 2,303 patients, with 1,150 patients randomized to TC PFO closure and 1,153 patients randomized to medical therapy. Mean follow-up was 3.5 years. Baseline characteristics (age, sex, and cardiovascular risk factors) were similar across studies. Intention-to-treat analyses showed a statistically significant risk reduction in stroke and/or transient ischemic attack in the TC PFO closure group when compared to medical treatment, pooled HR = 0.59, 95%CI (0.36-0.97), P = 0.04. The combined outcome of death, and vascular events, showed a borderline statistically significant benefit for TC PFO closure when compared to medical treatment, pooled HR = 0.67, 95%CI (0.44-1.00), P = 0.05 Subjects with a substantial PFO shunt seem to benefit the most with TC PFO closure, pooled HR = 0.35, 95%CI (0.12-1.03), P = 0.06, however, it did not reach statistical significance. These results suggest that in patients with cryptogenic stroke, TC PFO closure may be beneficial in reducing the risk of recurrent vascular events when compared to medical treatment. The benefit of TC PFO closure may be greater in patients with a substantial shunt.
Leaf-on canopy closure in broadleaf deciduous forests predicted during winter
Twedt, Daniel J.; Ayala, Andrea J.; Shickel, Madeline R.
2015-01-01
Forest canopy influences light transmittance, which in turn affects tree regeneration and survival, thereby having an impact on forest composition and habitat conditions for wildlife. Because leaf area is the primary impediment to light penetration, quantitative estimates of canopy closure are normally made during summer. Studies of forest structure and wildlife habitat that occur during winter, when deciduous trees have shed their leaves, may inaccurately estimate canopy closure. We estimated percent canopy closure during both summer (leaf-on) and winter (leaf-off) in broadleaf deciduous forests in Mississippi and Louisiana using gap light analysis of hemispherical photographs that were obtained during repeat visits to the same locations within bottomland and mesic upland hardwood forests and hardwood plantation forests. We used mixed-model linear regression to predict leaf-on canopy closure from measurements of leaf-off canopy closure, basal area, stem density, and tree height. Competing predictive models all included leaf-off canopy closure (relative importance = 0.93), whereas basal area and stem density, more traditional predictors of canopy closure, had relative model importance of ≤ 0.51.
Camacho-Mauries, Daniel; Rodriguez-Díaz, José Luis; Salgado-Nesme, Noel; González, Quintín H; Vergara-Fernández, Omar
2013-02-01
The use of temporary stomas has been demonstrated to reduce septic complications, especially in high-risk anastomosis; therefore, it is necessary to reduce the number of complications secondary to ostomy takedowns, namely wound infection, anastomotic leaks, and intestinal obstruction. To compare the rates of superficial wound infection and patient satisfaction after pursestring closure of ostomy wound vs conventional linear closure. Patients undergoing colostomy or ileostomy closure between January 2010 and February 2011 were randomly assigned to linear closure (n = 30) or pursestring closure (n = 31) of their ostomy wound. Wound infection within 30 days of surgery was defined as the presence of purulent discharge, pain, erythema, warmth, or positive culture for bacteria. Patient satisfaction, healing time, difficulty managing the wound, and limitation of activities were analyzed with the Likert questionnaire. The infection rate for the control group was 36.6% (n = 11) vs 0% in the pursestring closure group (p < 0.0001). Healing time was 5.9 weeks in the linear closure group and 3.8 weeks in the pursestring group (p = 0.0002). Seventy percent of the patients with pursestring closure were very satisfied in comparison with 20% in the other group (p = 0.0001). This study was limited by the heterogeneity in the type of stoma in both groups. The pursestring method resulted in the absence of infection after ostomy wound closure (shorter healing time and improved patient satisfaction).
Effectiveness and costs of overland skid trail BMPs
Clay Sawyers; W. Michael Aust; M. Chad Bolding; William A. Lakel III
2012-01-01
Forestry Best Management Practices (BMPs) are designed to protect water quality; however, little data exists comparing the efficacy and costs of different BMP options for skid trail closure. Study objectives were to evaluate erosion control effectiveness and implementation costs of five overland skid trail closure techniques. Closure techniques were: waterbar only (...
DOT National Transportation Integrated Search
2003-08-01
The objective of this report is to raise awareness among designers construction engineers, and managers of the applications and benefits of full road closure during rehabilitation and construction activities. Based on interviews with project personne...
NASA Astrophysics Data System (ADS)
Firl, G. J.; Randall, D. A.
2013-12-01
The so-called "assumed probability density function (PDF)" approach to subgrid-scale (SGS) parameterization has shown to be a promising method for more accurately representing boundary layer cloudiness under a wide range of conditions. A new parameterization has been developed, named the Two-and-a-Half ORder closure (THOR), that combines this approach with a higher-order turbulence closure. THOR predicts the time evolution of the turbulence kinetic energy components, the variance of ice-liquid water potential temperature (θil) and total non-precipitating water mixing ratio (qt) and the covariance between the two, and the vertical fluxes of horizontal momentum, θil, and qt. Ten corresponding third-order moments in addition to the skewnesses of θil and qt are calculated using diagnostic functions assuming negligible time tendencies. The statistical moments are used to define a trivariate double Gaussian PDF among vertical velocity, θil, and qt. The first three statistical moments of each variable are used to estimate the two Gaussian plume means, variances, and weights. Unlike previous similar models, plume variances are not assumed to be equal or zero. Instead, they are parameterized using the idea that the less dominant Gaussian plume (typically representing the updraft-containing portion of a grid cell) has greater variance than the dominant plume (typically representing the "environmental" or slowly subsiding portion of a grid cell). Correlations among the three variables are calculated using the appropriate covariance moments, and both plume correlations are assumed to be equal. The diagnosed PDF in each grid cell is used to calculate SGS condensation, SGS fluxes of cloud water species, SGS buoyancy terms, and to inform other physical parameterizations about SGS variability. SGS condensation is extended from previous similar models to include condensation over both liquid and ice substrates, dependent on the grid cell temperature. Implementations have been included in THOR to drive existing microphysical and radiation parameterizations with samples drawn from the trivariate PDF. THOR has been tested in a single-column model framework using standardized test cases spanning a range of large-scale conditions conducive to both shallow cumulus and stratocumulus clouds and the transition between the two states. The results were compared to published LES intercomparison results using the same cases, and the gross characteristics of both cloudiness and boundary layer turbulence produced by THOR were within the range of results from the respective LES ensembles. In addition, THOR was used in a single-column model framework to study low cloud feedbacks in the northeastern Pacific Ocean. Using initialization and forcings developed as part of the CGILS project, THOR was run at 8 points along a cross-section from the trade-wind cumulus region east of Hawaii to the coastal stratocumulus region off the coast of California for both the control climate and a climate perturbed by +2K SST. A neutral to weakly positive cloud feedback of 0-4 W m-2 K-1 was simulated along the cross-section. The physical mechanisms responsible appeared to be increased boundary layer entrainment and stratocumulus decoupling leading to reduced maximum cloud cover and liquid water path.
WADA, YUMA; MIYOSHI, NORIKATSU; OHUE, MASAYUKI; NOURA, SHINGO; FUJINO, SHIKI; SUGIMURA, KEIJIROU; AKITA, HIROFUMI; MOTOORI, MASAAKI; GOTOH, KUNIHITO; TAKAHASHI, HIDENORI; KOBAYASHI, SHOGO; OHMORI, TAKESHI; FUJIWARA, YOSHIYUKI; YANO, MASAHIKO
2015-01-01
The aim of this study was to compare the incidence of postoperative complications, including superficial incisional surgical site infection (SSI) following purse-string skin closure (PS) and conventional skin closure with a drainage tube (CD) following stoma closure. A total of 55 consecutive patients who underwent loop colostomy and loop ileostomy closures in our hospital between October, 2011 and September, 2014 were retrospectively assessed. The patients were divided into two groups, namely the PS group (26 patients) and the CD group (29 patients). There were no significant differences in the characteristics of the patients between the two groups. The baseline and operative characteristics also did not differ significantly between the two groups. However the incidence of superficial incisional SSI was lower in the PS group compared to that in the CD group (0 vs. 13.8%, respectively; P=0.049). The overall incidence of complications did not differ significantly between the two groups (P=0.313). The duration of postoperative hospital stay in the PS group was shorter compared to that in the CD group. In conclusion, the results of this study suggest that PS may an effective technique to reduce the incidence of superficial incisional SSI. This technique appears to be superior to the conventional technique, allowing for better cosmesis. PMID:26137277
Alivizatos, Vassilos; Felekis, Dimitrios; Zorbalas, Athanasios
2002-01-01
The aim of this study was to evaluate the effectiveness of Octreotide as an adjunct treatment to total parenteral nutrition in the spontaneous closure of postoperative enterocutaneous fistulas. Medical records of 39 patients with postoperative enterocutaneous fistulas treated in our Department between January 1988 and August 2000 were reviewed. Sixteen patients had duodenal fistulas and 23 had jejunal or ileal fistulas. According to the daily output, there were 20 low fistula output and 19 high fistula output. Conservative treatment consisted of nutritional support with total parenteral nutrition in all the patients. Administration of Octreotide (100 micrograms every 8 hours, subcutaneously) was done in 21 consecutive patients until spontaneous closure of the fistulas or their subsequent surgical closure. The occurrence of fistulas closure was compared using the Fisher's exact test. A mean reduction of 50% of fistula output was noted in all the patients who received Octreotide, within 24 hours of its administration. Spontaneous closure was achieved in 13 patients of the Octreotide group (mean closure time: 15.3 days, range: 6-35) and in 12 patients treated only with total parenteral nutrition (mean closure time: 13.9 days, range: 7-25); this difference was not significant (P = 0.5). Also, the fistula closure rate was not influenced by the anatomic site, the high or low output, and the age of the patient. The results of this study suggest that, as an adjunct treatment to total parenteral nutrition, Octreotide reduces rapidly the fistula output without significant influence in the spontaneous closure rate.
Mechanics of Wound Closure: Emerging Tape-Based Wound Closure Technology vs. Traditional Methods.
Levi, Kemal; Ichiryu, Kei; Kefel, Pelin; Keller, Juergen; Grice, Jon; Belson, Ori; Storne, Eric; Safa, Bauback
2016-10-12
To date, there is still a lack of understanding of how wound closure methods perform comparatively under daily bodily movement during the course of healing and how they affect the mechanics of healing. The present study is a first step in understanding and objectively quantifying the gap. The study provides both a new method of metrology for noninvasive evaluation of skin mechanics at the onset of wound healing and an emerging tape-based wound closure technology. The latter shows better performance with respect to commonly used staples and sutures, holding the wound intact and providing uniform mechanical support across the incision.
The TopClosure® 3S System, for skin stretching and a secure wound closure.
Topaz, Moris; Carmel, Narin-Nard; Silberman, Adi; Li, Ming Sen; Li, Yong Zhong
2012-07-01
The principle of stretching wound margins for primary wound closure is commonly practiced and used for various skin defects, leading at times to excessive tension and complications during wound closure. Different surgical techniques, skin stretching devices and tissue expanders have been utilized to address this issue. Previously designed skin stretching devices resulted in considerable morbidity. They were invasive by nature and associated with relatively high localized tissue pressure, frequently leading to necrosis, damage and tearing of skin at the wound margins. To assess the clinical effectiveness and performance and, to determine the safety of TopClosure® for gradual, controlled, temporary, noninvasive and invasive applications for skin stretching and secure wound closing, the TopClosure® device was applied to 20 patients for preoperative skin lesion removal and to secure closure of a variety of wound sizes. TopClosure® was reinforced with adhesives, staples and/or surgical sutures, depending on the circumstances of the wound and the surgeon's judgment. TopClosure® was used prior to, during and/or after surgery to reduce tension across wound edges. No significant complications or adverse events were associated with its use. TopClosure® was effectively used for preoperative skin expansion in preparation for dermal resection (e.g., congenital nevi). It aided closure of large wounds involving significant loss of skin and soft tissue by mobilizing skin and subcutaneous tissue, thus avoiding the need for skin grafts or flaps. Following surgery, it was used to secure closure of wounds under tension, thus improving wound aesthetics. A sample case study will be presented. We designed TopClosure®, an innovative device, to modify the currently practiced concept of wound closure by applying minimal stress to the skin, away from damaged wound edges, with flexible force vectors and versatile methods of attachment to the skin, in a noninvasive or invasive manner.
Evaluation of airway protection: Quantitative timing measures versus penetration/aspiration score.
Kendall, Katherine A
2017-10-01
Quantitative measures of swallowing function may improve the reliability and accuracy of modified barium swallow (MBS) study interpretation. Quantitative study analysis has not been widely instituted, however, secondary to concerns about the time required to make measures and a lack of research demonstrating impact on MBS interpretation. This study compares the accuracy of the penetration/aspiration (PEN/ASP) scale (an observational visual-perceptual assessment tool) to quantitative measures of airway closure timing relative to the arrival of the bolus at the upper esophageal sphincter in identifying a failure of airway protection during deglutition. Retrospective review of clinical swallowing data from a university-based outpatient clinic. Swallowing data from 426 patients were reviewed. Patients with normal PEN/ASP scores were identified, and the results of quantitative airway closure timing measures for three liquid bolus sizes were evaluated. The incidence of significant airway closure delay with and without a normal PEN/ASP score was determined. Inter-rater reliability for the quantitative measures was calculated. In patients with a normal PEN/ASP score, 33% demonstrated a delay in airway closure on at least one swallow during the MBS study. There was no correlation between PEN/ASP score and airway closure delay. Inter-rater reliability for the quantitative measure of airway closure timing was nearly perfect (intraclass correlation coefficient = 0.973). The use of quantitative measures of swallowing function, in conjunction with traditional visual perceptual methods of MBS study interpretation, improves the identification of airway closure delay, and hence, potential aspiration risk, even when no penetration or aspiration is apparent on the MBS study. 4. Laryngoscope, 127:2314-2318, 2017. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.
Fraire-Zamora, Juan Jose; Jaeger, Johannes; Solon, Jérôme
2018-03-14
Evolution of morphogenesis is generally associated with changes in genetic regulation. Here, we report evidence indicating that dorsal closure, a conserved morphogenetic process in dipterans, evolved as the consequence of rearrangements in epithelial organization rather than signaling regulation. In Drosophila melanogaster , dorsal closure consists of a two-tissue system where the contraction of extraembryonic amnioserosa and a JNK/Dpp-dependent epidermal actomyosin cable result in microtubule-dependent seaming of the epidermis. We find that dorsal closure in Megaselia abdita, a three-tissue system comprising serosa, amnion and epidermis, differs in morphogenetic rearrangements despite conservation of JNK/Dpp signaling. In addition to an actomyosin cable, M. abdita dorsal closure is driven by the rupture and contraction of the serosa and the consecutive microtubule-dependent seaming of amnion and epidermis. Our study indicates that the evolutionary transition to a reduced system of dorsal closure involves simplification of the seaming process without changing the signaling pathways of closure progression. © 2018, Fraire-Zamora et al.
Jaeger, Johannes
2018-01-01
Evolution of morphogenesis is generally associated with changes in genetic regulation. Here, we report evidence indicating that dorsal closure, a conserved morphogenetic process in dipterans, evolved as the consequence of rearrangements in epithelial organization rather than signaling regulation. In Drosophila melanogaster, dorsal closure consists of a two-tissue system where the contraction of extraembryonic amnioserosa and a JNK/Dpp-dependent epidermal actomyosin cable result in microtubule-dependent seaming of the epidermis. We find that dorsal closure in Megaselia abdita, a three-tissue system comprising serosa, amnion and epidermis, differs in morphogenetic rearrangements despite conservation of JNK/Dpp signaling. In addition to an actomyosin cable, M. abdita dorsal closure is driven by the rupture and contraction of the serosa and the consecutive microtubule-dependent seaming of amnion and epidermis. Our study indicates that the evolutionary transition to a reduced system of dorsal closure involves simplification of the seaming process without changing the signaling pathways of closure progression. PMID:29537962
Potter, Margaret A; Brown, Shawn T; Cooley, Phillip C; Sweeney, Patricia M; Hershey, Tina B; Gleason, Sherrianne M; Lee, Bruce Y; Keane, Christopher R; Grefenstette, John; Burke, Donald S
2012-11-14
States' pandemic influenza plans and school closure statutes are intended to guide state and local officials, but most faced a great deal of uncertainty during the 2009 influenza H1N1 epidemic. Questions remained about whether, when, and for how long to close schools and about which agencies and officials had legal authority over school closures. This study began with analysis of states' school-closure statutes and pandemic influenza plans to identify the variations among them. An agent-based model of one state was used to represent as constants a population's demographics, commuting patterns, work and school attendance, and community mixing patterns while repeated simulations explored the effects of variations in school closure authority, duration, closure thresholds, and reopening criteria. The results show no basis on which to justify statewide rather than school-specific or community-specific authority for school closures. Nor do these simulations offer evidence to require school closures promptly at the earliest stage of an epidemic. More important are criteria based on monitoring of local case incidence and on authority to sustain closure periods sufficiently to achieve epidemic mitigation. This agent-based simulation suggests several ways to improve statutes and influenza plans. First, school closure should remain available to state and local authorities as an influenza mitigation strategy. Second, influenza plans need not necessarily specify the threshold for school closures but should clearly define provisions for early and ongoing local monitoring. Finally, school closure authority may be exercised at the statewide or local level, so long as decisions are informed by monitoring incidence in local communities and schools.
Arango-Lasprilla, Juan Carlos; Ketchum, Jessica M; Hurley, Jessica; Getachew, Almaz M; Gary, Kelli Williams
2014-01-01
Approximately 25% of working-aged Americans with disabilities work full or part time, yet still face discrimination despite the passing of the American's with Disabilities Act (ADA) over 20 years ago. To determine if the proportion of allegations of ADA Title I workplace discrimination with merit closed at any year between 1993 and 2008 differs among Whites, African Americans, Hispanics, and Asians; to determine if there was a change over time from 1993 to 2008 in merit closure rate within each race/ethnicity group; and to determine whether changes over time between 1993 and 2008 in the merit closure rate differ among the race/ethnicity groups. Logistic regression was used for this cross-sectional panel study to model the merit closure rate for each ethnic group from 1993 to 2008 using 318,587 charging parties from the EEOC database. All ethnic groups exhibited significant changes over time in the merit closure rate. There were significant differences in the closure rates among the race/ethnicity groups specifically at closure years 1995-2000, 2002, 2003, and 2006. Finally, there was evidence that the trends in merit closure rates over time differed significantly among the race/ethnicity groups. There was significant evidence that the proportion of claims closed with merit was significantly different among the racial/ethnicity groups.
Limited utility of preoperative studies in preparation for colostomy closure.
Pokorny, R M; Heniford, T; Allen, J W; Tuckson, W B; Galandiuk, S
1999-04-01
Numerous diagnostic and therapeutic practices are used in an attempt to reduce the morbidity of colostomy closures. Our principal aim was to evaluate the role of preoperative studies, specifically barium enemas and endoscopic examinations, performed before colostomy closures. Additionally, we wished to identify other practices involved in the perioperative management of patients undergoing colostomy closure that influenced morbidity. The records of 100 consecutive patients who underwent elective colostomy closure at University of Louisville Hospital between January 1989 and July 1995 were reviewed. Wound infection was the most common complication (12%). Various bowel preparations were equivalent in efficacy and did not influence the complication rate. Intermittent wound irrigation with antibiotics for 3 days postoperatively, via subcutaneous drains, was associated with a low incidence of incision infection. Preoperative barium enema or sigmoidoscopy were often performed but rarely useful. Performing these examinations merely increased hospital cost without a corresponding decline in morbidity.
Single-site neural tube closure in human embryos revisited.
de Bakker, Bernadette S; Driessen, Stan; Boukens, Bastiaan J D; van den Hoff, Maurice J B; Oostra, Roelof-Jan
2017-10-01
Since the multi-site closure theory was first proposed in 1991 as explanation for the preferential localizations of neural tube defects, the closure of the neural tube has been debated. Although the multi-site closure theory is much cited in clinical literature, single-site closure is most apparent in literature concerning embryology. Inspired by Victor Hamburgers (1900-2001) statement that "our real teacher has been and still is the embryo, who is, incidentally, the only teacher who is always right", we decided to critically review both theories of neural tube closure. To verify the theories of closure, we studied serial histological sections of 10 mouse embryos between 8.5 and 9.5 days of gestation and 18 human embryos of the Carnegie collection between Carnegie stage 9 (19-21 days) and 13 (28-32 days). Neural tube closure was histologically defined by the neuroepithelial remodeling of the two adjoining neural fold tips in the midline. We did not observe multiple fusion sites in neither mouse nor human embryos. A meta-analysis of case reports on neural tube defects showed that defects can occur at any level of the neural axis. Our data indicate that the human neural tube fuses at a single site and, therefore, we propose to reinstate the single-site closure theory for neural tube closure. We showed that neural tube defects are not restricted to a specific location, thereby refuting the reasoning underlying the multi-site closure theory. Clin. Anat. 30:988-999, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.
Jin, Xiao-Fang; Ye, Zhong-Ming; Amboka, Grace M.; Wang, Qing-Feng; Yang, Chun-Feng
2017-01-01
A sensitive bilobed stigma is thought to assure reproduction, avoid selfing and promote outcrossing. In addition, it may also play a role in pollinator selection since only pollinators with the appropriate body size can trigger this mechanism. However, no experimental study has investigated how the sensitive stigma responds to different pollinators and its potential effects on pollination. Mazus miquelii (Phrymaceae), a plant with a bilobed stigma was studied to investigate the relationship between stigma behaviors and its multiple insect pollinators. The reaction time of stigma closure after touched, duration of temporary closure, and factors determining permanent closure of the stigma were studied when flowers were exposed to different visitors and conducted with hand pollination. Manual stimulation was also used to detect the potential differences in stigmas when touched with different degrees of external forces. Results indicated that, compared to pollinators with a small body size, larger pollinators transferred more pollen grains to the stigma, causing a rapid stigma response and resulting in a higher percentage of permanent closures. Duration of temporary closure was negatively correlated with the speed of stigma closure; a stigma that closed more rapidly reopened more slowly. Manual stimulation showed that reaction time of stigma closure was likely a response to external mechanical forces. Hand pollination treatments revealed that the permanent closure of a stigma was determined by the size of stigmatic pollen load. For large pollinators, the speedy reaction of the stigma might help to reduce pollen loss, enhance pollen germination and avoid obstructing pollen export. Stigmas showed low sensitivity when touched by inferior pollinators, which may have increased the possibility of pollen deposition by subsequent visits. Therefore, the stigma behavior in M. miquelii is likely a mechanism of pollinator selection to maximize pollination success. PMID:28539934
Do we need a femoral artery route for transvenous PDA closure in children with ADO-I?
Baykan, Ali; Narin, Nazmi; Özyurt, Abdullah; Argun, Mustafa; Pamukçu, Özge; Onan, Sertaç H; Sezer, Sadettin; Baykan, Zeynep; Üzüm, Kazım
2015-03-01
The standard procedure in percutaneous closure of patent ductus arteriosus (PDA) with Amplatzer duct occluder-I (ADO-I) is transvenous closure guided by aortic access through femoral artery. The current study aims to compare the procedures for PDA closure with ADO-I: only transvenous access with the standard procedure. This study was designed retrospectively and 101 pediatric patients were included. PDA closure was done by only femoral venous access in 19 of them (group 1), arterial and venous access used in 92 patients (group 2) between 2004 to 2012 years. The position of the device and residual shunt in group1 was evaluated by the guidance of the aortogram obtained during the return phase of the pulmonary artery injection and guidance of transthoracic echocardiography. Shapiro-Wilk's test, Mann-Whitney U, chi-squared tests were used for statistical comparison. The procedure was successful in 18 (95%) patients in group 1 and 90 (98%) patients in group 2. Complications including the pulmonary artery embolization (n=1), protrusion to pulmonary artery (n=1), inguinal hematoma (n=3), bleeding (n=2) were only detected in group 2. In other words, while complications were observed in 7 (7.2%) patients in group 2, no minor/major complication was observed in group 1. Complete closure in group 1 was: in catheterization room 14 (77.8%), at 24th hour in 2 (11.1%), at first month in 2 (11.1%). Complete closure in group 2 was: 66 (73.4%) patients in the catheterization room, 21 (23.3%) at 24th hour, 3 (3.3%) at first month, complete closure occurred at the end of first month. In percutaneouse PDA closure via ADO-I, this technique can be a choice for patients whose femoral artery could not be accessed, or access is impossible/contraindicated. But for the reliability and validity of this method, randomized multicenter clinical studies are necessary.
Do we need a femoral artery route for transvenous PDA closure in children with ADO-I?
Baykan, Ali; Narin, Nazmi; Özyurt, Abdullah; Argun, Mustafa; Pamukçu, Özge; Onan, Sertaç H.; Sezer, Sadettin; Baykan, Zeynep; Üzüm, Kazım
2015-01-01
Objective: The standard procedure in percutaneous closure of patent ductus arteriosus (PDA) with Amplatzer duct occluder-I (ADO-I) is transvenous closure guided by aortic access through femoral artery. The current study aims to compare the procedures for PDA closure with ADO-I: only transvenous access with the standard procedure. Methods: This study was designed retrospectively and 101 pediatric patients were included. PDA closure was done by only femoral venous access in 19 of them (group 1), arterial and venous access used in 92 patients (group 2) between 2004 to 2012 years. The position of the device and residual shunt in group1 was evaluated by the guidance of the aortogram obtained during the return phase of the pulmonary artery injection and guidance of transthoracic echocardiography. Shapiro-Wilk’s test, Mann-Whitney U, chi-squared tests were used for statistical comparison. Results: The procedure was successful in 18 (95%) patients in group 1 and 90 (98%) patients in group 2. Complications including the pulmonary artery embolization (n=1), protrusion to pulmonary artery (n=1), inguinal hematoma (n=3), bleeding (n=2) were only detected in group 2. In other words, while complications were observed in 7 (7.2%) patients in group 2, no minor/major complication was observed in group 1. Complete closure in group 1 was: in catheterization room 14 (77.8%), at 24th hour in 2 (11.1%), at first month in 2 (11.1%). Complete closure in group 2 was: 66 (73.4%) patients in the catheterization room, 21 (23.3%) at 24th hour, 3 (3.3%) at first month, complete closure occurred at the end of first month. Conclusion: In percutaneouse PDA closure via ADO-I, this technique can be a choice for patients whose femoral artery could not be accessed, or access is impossible/contraindicated. But for the reliability and validity of this method, randomized multicenter clinical studies are necessary. PMID:25333978
Efficacy of stapler pharyngeal closure after total laryngectomy: A systematic review.
Aires, Felipe T; Dedivitis, Rogério A; Castro, Mario Augusto F; Bernardo, Wanderley Marques; Cernea, Claudio Roberto; Brandão, Lenine Garcia
2014-05-01
Some primary studies compare manual and mechanical pharyngeal closures after total laryngectomy. The purpose of this study was to evaluate the advantages of the mechanical suture in pharyngeal closure. The literature survey included research in MEDLINE, EMBASE, and LILACS. The intervention analyzed was stapler-assisted pharyngeal closure, whereas the control group was manual suture pharyngeal closure. The survey resulted in 319 studies. However, 4 studies were selected (417 patients). In the group of patients in whom the stapler was used, the incidence of pharyngocutaneous fistula was 8.7%, whereas in the other, it was 22.9%, with an absolute risk reduction of 15% (95% confidence interval [CI], 0.02-0.28; p = .02; I(2) = 66%). Regarding the surgical time, the average difference was 80 minutes in favor of the stapler group (95% CI, 23.16-136.58 minutes; p < .006). The difference for starting oral feeding was 8 days in favor of the mechanical suture (95% CI, 4.01-11.73 days; p < .001). Patients who underwent mechanical suture had a shorter hospitalization period. Copyright © 2013 Wiley Periodicals, Inc.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pieper, Claus Christian, E-mail: claus.christian.pieper@ukb.uni-bonn.de; Thomas, Daniel, E-mail: daniel.thomas@ukb.uni-bonn.de; Nadal, Jennifer, E-mail: jennifer.nadal@ukb.uni-bonn.de
PurposeTo intra-individually compare discomfort levels and patient satisfaction after arterial access closure using the ExoSeal{sup ®} vascular closure device (VCD) and manual compression (MC) in a prospective study design.MethodsPatients undergoing two planned interventions from 07/2013 to 09/2014 could participate in the study. Access closure was performed with an ExoSeal{sup ®}-VCD in one and MC in the other intervention. Patients were clinically and sonographically examined and were given questionnaires 1 day after intervention [groin- and back-pain during bedrest (100-point visual analog scale; 0: no pain); comfortability of bedrest (10-point Likert scale, 1: comfortable), satisfaction with closure (10-point Likert scale, 1: very satisfied)].more » Results were analyzed in a cross-over design.Results48 patients (29 male, median age 62.5 (32–88) years) were included. An ExoSeal{sup ®}-VCD was used first in 25 cases. As four of these subsequently refused MC as second intervention, data from 44 patients could be analyzed. All closures were technically successful (successful device deployment) without major complications. Groin- and back-pain after VCD-use/MC was 0 (0–15) vs. 10 (0–80) and 0 (0–75) vs. 25 (0–90), respectively (p < 0.0001). Bedrest after VCD-use was more comfortable than after MC [1 (range 1–7) vs. 6 (2–10); p < 0.0001]. Satisfaction with the closure procedure and with the intervention in general was higher after VCD-use compared to MC [1 (1–3) vs. 5 (2–10) and 1 (1–2) vs. 2 (1–4), respectively; p < 0.0001].ConclusionIntra-individual comparison showed pain levels and discomfort to be significantly lower after ExoSeal{sup ®} use compared to MC. VCD closure was associated with higher satisfaction both with the closure itself and with the intervention in general.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
1996-07-01
The module explains the difference between closure and post-closure. It lists the types of facilities that are subject to closure/post-closures and defines the difference between partial and final closure. It specifies who submits a closure plan and when a closure plan must be submitted, lists the steps in the process, and states the time frame for submittal. It identifies when and how a closure must be amended. It explains the time frame for notification of closure and the deadlines for beginning and completing closure. It specifies which facilities need contingent post-closure plans and lists and the elements of post-closure andmore » cites the requirements. It specifies the conditions and timing for amending a post-closure plan and states who must certify closure/post-closure.« less
Darmoch, Fahed; Al-Khadra, Yasser; Soud, Mohamad; Fanari, Zaher; Alraies, M Chadi
2018-01-01
Patent foramen ovale (PFO) with atrial septal aneurysm is suggested as an important potential source for cryptogenic strokes. Percutaneous PFO closure to reduce the recurrence of stroke compared to medical therapy has been intensely debated. The aim of this study is to assess whether PFO closure in patients with cryptogenic stroke is safe and effective compared with medical therapy. A search of PubMed, Medline, and Cochrane Central Register from January 2000 through September 2017 for randomized controlled trails (RCT), which compared PFO closure to medical therapy in patients with cryptogenic stroke was conducted. We used the items "PFO or patent foramen ovale", "paradoxical embolism", "PFO closure" and "stroke". Data were pooled for the primary outcome measure using the random-effects model as pooled rate ratio (RR). The primary outcome was reduction in recurrent strokes. Among 282 studies, 5 were selected. Our analysis included 3,440 patients (mean age 45 years, 55% men, mean follow-up 2.9 years), 1,829 in the PFO closure group and 1,611 in the medical therapy group. The I2 heterogeneity test was found to be 48%. A random effects model combining the results of the included studies demonstrated a statistically significant risk reduction in risk of recurrent stroke in the PFO closure group when compared with medical therapy (RR 0.42; 95% CI 0.20-0.91, p = 0.03). Pooled data from 5 large RCTs showed that PFO closure in patients with cryptogenic stroke is safe and effective intervention for prevention of stroke recurrence compared with medical therapy. © 2018 S. Karger AG, Basel.
Venkataraman, Ganesh; Strickberger, S Adam; Doshi, Shephal; Ellis, Christopher R; Lakkireddy, Dhanunjaya; Whalen, S Patrick; Cuoco, Frank
2018-01-01
Left atrial appendage (LAA) closure with the WATCHMAN device, according to FDA labelling, is recommended in patients with a maximal LAA ostial width between 17 and 31 mm. The safety and efficacy of LAA closure in patients with a maximal LAA ostial width < 17 mm has not been evaluated. The goal of this study was to determine the acute and short-term safety and efficacy of LAA closure with the WATCHMAN device in patients with a maximal LAA ostial width < 17 mm. Thirty-two consecutive patients with a maximal LAA ostial width < 17 mm as determined by a screening transesophageal echocardiogram (TEE) underwent LAA closure with the WATCHMAN device between March 2015 and November 2016 at five medical centers, and were included in this study. Mean age, body mass index (BMI), and CHA 2 DS 2 -VASC score were 70.8 ± 8.6 years, 29.3 ± 6.5 kg/m 2 , and 3.9 ±1.2, respectively. At the screening TEE, mean maximal LAA ostial width and depth were 15.6 ± 0.6 mm (range 14-16) and 23.2 ± 4.5 mm (range 13-31), respectively. Successful LAA closure with the WATCHMAN device was achieved in 31 of 32 patients (97%), with no major complications. TEE performed 45 days after LAA closure demonstrated no peridevice leak > 5 mm and no device related thrombi. Warfarin was discontinued in all 31 patients 45 days after LAA closure. LAA closure with the WATCHMAN device can be successfully and safely achieved in patients with a maximal LAA ostial width < 17 mm. © 2017 Wiley Periodicals, Inc.
Dissipative closures for statistical moments, fluid moments, and subgrid scales in plasma turbulence
NASA Astrophysics Data System (ADS)
Smith, Stephen Andrew
1997-11-01
Closures are necessary in the study physical systems with large numbers of degrees of freedom when it is only possible to compute a small number of modes. The modes that are to be computed, the resolved modes, are coupled to unresolved modes that must be estimated. This thesis focuses on dissipative closures models for two problems that arises in the study of plasma turbulence: the fluid moment closure problem and the subgrid scale closure problem. The fluid moment closures of Hammett and Perkins (1990) were originally applied to a one-dimensional kinetic equation, the Vlasov equation. These closures are generalized in this thesis and applied to the stochastic oscillator problem, a standard paradigm problem for statistical closures. The linear theory of the Hammett- Perkins closures is shown to converge with increasing numbers of moments. A novel parameterized hyperviscosity is proposed for two- dimensional drift-wave turbulence. The magnitude and exponent of the hyperviscosity are expressed as functions of the large scale advection velocity. Traditionally hyperviscosities are applied to simulations with a fixed exponent that must be arbitrarily chosen. Expressing the exponent as a function of the simulation parameters eliminates this ambiguity. These functions are parameterized by comparing the hyperviscous dissipation to the subgrid dissipation calculated from direct numerical simulations. Tests of the parameterization demonstrate that it performs better than using no additional damping term or than using a standard hyperviscosity. Heuristic arguments are presented to extend this hyperviscosity model to three-dimensional (3D) drift-wave turbulence where eddies are highly elongated along the field line. Preliminary results indicate that this generalized 3D hyperviscosity is capable of reducing the resolution requirements for 3D gyrofluid turbulence simulations.
Roushdy, Alaa; Abd El Razek, Yasmeen; Mamdouh Tawfik, Ahmed
2018-01-01
To determine anatomic and hemodynamic echocardiographic predictors for patent ductus arteriosus (PDA) device vs coil closure. Seventy-six patients who were referred for elective transcatheter PDA closure were enrolled in the study. All patients underwent full echocardiogram including measurement of the PDA pulmonary end diameter, color flow width and extent, peak and end-diastolic Doppler gradients across the duct, diastolic flow reversal, left atrial dimensions and volume, left ventricular sphericity index, and volumes. The study group was subdivided into 2 subgroups based on the mode of PDA closure whether by coil (n = 42) or device (n = 34). Using univariate analysis there was a highly significant difference between the 2 groups as regard the pulmonary end diameter measured in both the suprasternal and parasternal short-axis views as well as the color flow width and color flow extent (P < .0001). The device closure group had statistically significant higher end-systolic and end-diastolic volumes indexed, left atrial volume, and diastolic flow reversal. Receiver operating characteristic curve analysis showed a pulmonary end diameter cutoff point from the suprasternal view > 2.5 mm and from parasternal short-axis view > 2.61 mm to have the highest balanced sensitivity and specificity to predict the likelihood for device closure (AUC 0.971 and 0.979 respectively). The pulmonary end diameter measured from the suprasternal view was the most independent predictor of device closure. The selection between PDA coil or device closure can be done on the basis of multiple anatomic and hemodynamic echocardiographic variables. © 2017 Wiley Periodicals, Inc.
Anterior Segment Imaging Predicts Incident Gonioscopic Angle Closure.
Baskaran, Mani; Iyer, Jayant V; Narayanaswamy, Arun K; He, Yingke; Sakata, Lisandro M; Wu, Renyi; Liu, Dianna; Nongpiur, Monisha E; Friedman, David S; Aung, Tin
2015-12-01
To investigate the incidence of gonioscopic angle closure after 4 years in subjects with gonioscopically open angles but varying degrees of angle closure detected on anterior segment optical coherence tomography (AS OCT; Visante; Carl Zeiss Meditec, Dublin, CA) at baseline. Prospective, observational study. Three hundred forty-two subjects, mostly Chinese, 50 years of age or older, were recruited, of whom 65 were controls with open angles on gonioscopy and AS OCT at baseline, and 277 were cases with baseline open angles on gonioscopy but closed angles (1-4 quadrants) on AS OCT scans. All subjects underwent gonioscopy and AS OCT at baseline (horizontal and vertical single scans) and after 4 years. The examiner performing gonioscopy was masked to the baseline and AS OCT data. Angle closure in a quadrant was defined as nonvisibility of the posterior trabecular meshwork by gonioscopy and visible iridotrabecular contact beyond the scleral spur in AS OCT scans. Gonioscopic angle closure in 2 or 3 quadrants after 4 years. There were no statistically significant differences in age, ethnicity, or gender between cases and controls. None of the control subjects demonstrated gonioscopic angle closure after 4 years. Forty-eight of the 277 subjects (17.3%; 95% confidence interval [CI], 12.8-23; P < 0.0001) with at least 1 quadrant of angle closure on AS OCT at baseline demonstrated gonioscopic angle closure in 2 or more quadrants, whereas 28 subjects (10.1%; 95% CI, 6.7-14.6; P < 0.004) demonstrated gonioscopic angle closure in 3 or more quadrants after 4 years. Individuals with more quadrants of angle closure on baseline AS OCT scans had a greater likelihood of gonioscopic angle closure developing after 4 years (P < 0.0001, chi-square test for trend for both definitions of angle closure). Anterior segment OCT imaging at baseline predicts incident gonioscopic angle closure after 4 years among subjects who have gonioscopically open angles and iridotrabecular contact on AS OCT at baseline. Copyright © 2015 American Academy of Ophthalmology. All rights reserved.
Han, S; Humphreys, G W; Chen, L
1999-10-01
The role of perceptual grouping and the encoding of closure of local elements in the processing of hierarchical patterns was studied. Experiments 1 and 2 showed a global advantage over the local level for 2 tasks involving the discrimination of orientation and closure, but there was a local advantage for the closure discrimination task relative to the orientation discrimination task. Experiment 3 showed a local precedence effect for the closure discrimination task when local element grouping was weakened by embedding the stimuli from Experiment 1 in a background made up of cross patterns. Experiments 4A and 4B found that dissimilarity of closure between the local elements of hierarchical stimuli and the background figures could facilitate the grouping of closed local elements and enhanced the perception of global structure. Experiment 5 showed that the advantage for detecting the closure of local elements in hierarchical analysis also held under divided- and selective-attention conditions. Results are consistent with the idea that grouping between local elements takes place in parallel and competes with the computation of closure of local elements in determining the selection between global and local levels of hierarchical patterns for response.
Hadad, Bat-Sheva; Kimchi, Ruth
2006-11-01
In two experiments, visual search was used to study the grouping of shape on the basis of perceptual closure among participants 5-23 years of age. We first showed that young children, like adults, demonstrate an efficient search for a concave target among convex distractors for closed connected stimuli but an inefficient search for open stimuli. Reliable developmental differences, however, were observed in search for fragmented stimuli as a function of spatial proximity and collinearity between the closure-inducing fragments. When only closure was available, search for all the age groups was equally efficient for spatially close fragments and equally inefficient for spatially distant fragments. When closure and collinearity were available, search for spatially close fragments was equally efficient for all the age groups, but search for spatially distant fragments was inefficient for younger children and improved significantly between ages 5 and 10. These findings suggest that young children can utilize closure as efficiently as can adults for the grouping of shape for closed or nearly closed stimuli. When the closure-inducing fragments are spatially distant, only older children and adults, but not 5-year-olds, can utilize collinearity to enhance closure for the perceptual grouping of shape.
Reduction of the closure time of postoperative enterocutaneous fistulas with fibrin sealant.
Avalos-González, Jorge; Portilla-deBuen, Eliseo; Leal-Cortés, Caridad Aurea; Orozco-Mosqueda, Abel; Estrada-Aguilar, María del Carmen; Velázquez-Ramírez, Gabriela Abigail; Ambriz-González, Gabriela; Fuentes-Orozco, Clotilde; Guzmán-Gurrola, Aldo Emmerson; González-Ojeda, Alejandro
2010-06-14
To assess whether the use of fibrin sealant shortens the closure time of postoperative enterocutaneous fistulas (ECFs). The prospective case-control study included 70 patients with postoperative ECFs with an output of < 500 mL/d, a fistulous tract of > 2 cm and without any local complication. They were divided into study (n = 23) and control groups (n = 47). Esophageal, gastric and colocutaneous fistulas were monitored under endoscopic visualization, which also allowed fibrin glue application directly through the external hole. Outcome variables included closure time, time to resume oral feeding and morbidity related to nutritional support. There were no differences in mean age, fistula output, and follow-up. Closure-time for all patients of the study group was 12.5 +/- 14.2 d and 32.5 +/- 17.9 d for the control group (P < 0.001), and morbidity related to nutritional support was 8.6% and 42.5%, respectively (P < 0.01). In patients with colonic fistulas, complete closure occurred 23.5 +/- 19.5 d after the first application of fibrin glue, and spontaneous closure was observed after 36.2 +/- 22.8 d in the control group (P = 0.36). Recurrences were observed in 2 patients because of residual disease. One patient of each group died during follow-up as a consequence of septic complications related to parenteral nutrition. Closure time was significantly reduced with the use of fibrin sealant, and oral feeding was resumed faster. We suggest the use of fibrin sealant for the management of stable enterocutaneous fistulas.
Gingras, Kristen; Zaruby, Jeffrey; Maul, Don
2012-05-01
The objective of this study was to compare the biomechanical strength of two barbed suture devices: V-Loc™ 180 Wound Closure Device and Quill™ PDO Knotless Tissue-Closure Device following primary cosmetic skin closures in a porcine dermal model. This prospective randomized, controlled in vivo trial compared size 3/0 V-Loc™ 180 device to size 2/0 Quill™ PDO device. Both products were tested for dermal closure in adult porcine models and evaluated at five timepoints. At postoperative days 0, 3, 7, 14, and 28 sutured tissue regions were excised post mortem and tested for intradermal wound holding strength. Wounds closed with V-Loc™ 180 device were stronger than Quill™ PDO device at days 0, 3, 7, and 14 with these differences being significant (p < 0.05) at days 3 and 7. At day 3, the average maximum load of V-Loc™ 180 was 13.53 kgf and Quill™ PDO was 10.38 kgf (p = 0.002). At day 7, the average maximum load of V-Loc™ 180 was 10.4 kgf and Quill™ PDO was 7.56 kgf (p = 0.001). Throughout the duration of the study, there was no suture extrusion or tissue distortion and all wounds healed with no major complications. In this study, V-Loc™ 180 device was significantly stronger than Quill™ PDO device during the critical phases of wound healing in skin. Copyright © 2012 Wiley Periodicals, Inc.
Lee, Janet T; Marquez, Thao T; Clerc, Daniel; Gie, Olivier; Demartines, Nicolas; Madoff, Robert D; Rothenberger, David A; Christoforidis, Dimitrios
2014-11-01
Surgical site infection after stoma reversal is common. The optimal skin closure technique after stoma reversal has been widely debated in the literature. We hypothesized that pursestring near-complete closure of the stoma site would lead to fewer surgical site infections compared with conventional primary closure. This study was a parallel prospective multicenter randomized controlled trial. This study was conducted at 2 university medical centers. Patients (N = 122) presenting for elective colostomy or ileostomy reversal were selected. Pursestring versus conventional primary closure of stoma sites were compared. Stoma site surgical site infection within 30 days of surgery, overall surgical site infection, delayed healing (open wound for >30 days), time to wound epithelialization, and patient satisfaction were the primary outcomes measured. The pursestring group had a significantly lower stoma site infection rate (2% vs 15%, p = 0.01). There was no difference in delayed healing or patient satisfaction between groups. Time to epithelialization was measured in only 51 patients but was significantly longer in the pursestring group (34.6 ± 20 days vs 24.1 ± 17 days, p = 0.02). This study was limited by the variability in procedures and surgeons, the limited follow-up after 30 days, and the inability to perform blinding. Pursestring closure after stoma reversal has a lower risk of stoma site surgical site infection than conventional primary closure, although wounds may take longer to heal with the use of this approach. NCT01713452 (www.clinicaltrials.gov).
Subcostal closure technique for prevention of postthoracotomy pain syndrome.
Hong, Kipyo; Bae, Mikyung; Han, Sora
2016-09-01
The purpose of this study was to evaluate the efficacy of our subcostal closure technique in prevention of postthoracotomy pain syndrome. From July 2012 to March 2015, 29 patients in whom a lobectomy was indicated underwent a thoracotomy. The thoracotomy wounds were closed using a subcostal closure technique (subcostal closure group) and outcomes were compared with 31 patients who underwent video-assisted thoracoscopic surgery (thoracoscopy group). The duration of oral opioid consumption was evaluated from medical records, and postoperative pain was evaluated by telephone interview conducted by a trained nurse practitioner who was unaware of the patient's group. Pain scores were higher in the thoracoscopy group compared to the subcostal closure group, reaching statistical significance (Numeric Rating Scale 0.55 ± 0.948 in the subcostal closure group vs. 1.84 ± 1.614 in the thoracoscopy group; p < 0.001, Clinical Pain Scale 0.24 ± 0.435 in the subcostal closure group vs. 0.81 ± 0.703 in the thoracoscopy group; p < 0.001). The number of patients who consumed oral opioids for longer than 2 months after the operation was significantly greater in the thoracoscopy group than the subcostal closure group (6.9% in the subcostal closure group vs. 32.3% in the thoracoscopy group; p = 0.022). The subcostal closure technique is useful to prevent postthoracotomy pain syndrome. © The Author(s) 2016.
Bosse, Michael J; Murray, Clinton K; Carlini, Anthony R; Firoozabadi, Reza; Manson, Theodore; Scharfstein, Daniel O; Wenke, Joseph C; Zadnik, Mary; Castillo, Renan C
2017-04-01
Infection remains the most common and significant complication after high-energy fractures. The Bioburden Study is a multicenter, prospective, observational cohort study of wound bacterial bioburden and antibiotic care in severe open lower extremity fractures. The aims of this study are to (1) characterize the contemporary extremity wound "bioburden" at the time of definitive wound closure; (2) determine the concordance between polymerase chain reaction results and hospital microbiology; (3) determine, among those who develop deep infections, the concordance between the pathogens at wound closure and at deep infection; and (4) compare the probability of deep infection between those who did and did not receive an appropriate course of antibiotics based on bioburden at the time of wound closure. To address these aims, sites collected tissue samples from severe lower extremity injuries at the time of wound closure and at first surgery for treatment of a deep infection, nonunion, flap failure, amputation, or other complications (because these surgeries may be due to undetected infection). Otherwise, if no further surgical treatment occurred, participants were followed for 12 months. The study was conducted at 38 US trauma centers and has enrolled 655 participants aged 18-64 years. This is the first large multi-institutional study evaluating the wound bioburden of severe open tibia fractures and correlating this bioburden with the risk of wound complications after definitive soft tissue closure.
High expression of A-type lamin in the leading front is required for Drosophila thorax closure.
Kosakamoto, Hina; Fujisawa, Yuya; Obata, Fumiaki; Miura, Masayuki
2018-05-05
Tissue closure involves the coordinated unidirectional movement of a group of cells without loss of cell-cell contact. However, the molecular mechanisms controlling the tissue closure are not fully understood. Here, we demonstrate that Lamin C, the sole A-type lamin in Drosophila, contributes to the process of thorax closure in pupa. High expression of Lamin C was observed at the leading front of the migrating wing imaginal discs. Live imaging analysis revealed that knockdown of Lamin C in the thorax region affected the coordinated movement of the leading front, resulting in incomplete tissue fusion required for formation of the adult thorax. The closure defect due to knockdown of Lamin C correlated with insufficient accumulation of F-actin at the front. Our study indicates a link between A-type lamin and the cell migration behavior during tissue closure. Copyright © 2018 Elsevier Inc. All rights reserved.
Predictors of successful closure of patent ductus arteriosus with indomethacin.
Ahamed, M F; Verma, P; Lee, S; Vega, M; Wang, D; Kim, M; Fuloria, M
2015-09-01
To determine whether platelet counts can predict the likelihood of successful closure of patent ductus arteriosus (PDA) with indomethacin. This was a retrospective cohort study of infants <32 weeks' gestational age (GA) and birth weight <1500 g with PDA. Clinical characteristics between infants who achieved ductal closure with indomethacin and those who failed were compared. Multivariable logistic regression was used to identify predictors of successful ductal closure. In infants with hemodynamically significant PDA, older GA (odds ratio=1.54; 95% confidence interval: 1.12 to 2.13), male gender (odds ratio=3.02; 95% confidence interval: 1.08 to 8.49) and higher platelet count (odds ratio=1.5; 95% confidence interval: 1.04 to 2.17) prior to indomethacin treatment were associated with successful ductal closure with indomethacin. Older GA, male gender and higher platelet count at time of treatment of hemodynamically significant PDA are predictors of successful ductal closure with indomethacin.
Transcatheter Closure of Patent Ductus Arteriosus in Children with the Occlutech Duct Occluder.
Bilici, Meki; Demir, Fikri; Akın, Alper; Türe, Mehmet; Balık, Hasan; Kuyumcu, Mahir
2017-12-01
The aim of this study was to evaluate the feasibility, efficacy and safety of transcatheter closure of patent ductus arteriosus (PDA) with the Occlutech duct occluder (ODO) in children. We reviewed the clinical records of 71 patients who underwent percutaneous closure of PDA with an ODO between September 2014 and August 2016. The Occlutech duct occluder was applied to 71 patients during the study period (September 2014-August 2016), and the results were analyzed in this study. Forty-two of the patients were female and 29 male. The median age was 20.5 months (range, 6-194 months) and median weight was 16 kg (range, 6-68 kg). The PDA was classified as type A in 54 patients (76.1%), type E in 14 (19.7%), type C in 2 (2.8%) and type B in 1 (1.4%) based on the Krichenko classification. A standard ODO device was used for the transcatheter closure procedure in 66 patients and the long-shank ODO device in 5. In the echocardiographic measurement of PDA, the median smallest diameter was 2.7 mm (range, 1.5-7.0 mm), and in the angiographic measurement, the median smallest diameter was 2.5 mm (range, 1.5-6.5 mm). All 71 patients underwent successful PDA closure with the ODO. Angiography following the procedure showed complete closure in 47 patients (66.2%), mild residual shunt in 13 patients (18.3%) and a trivial shunt in 11 patients (15.5%). Color flow Doppler echocardiogpaphy at 24 h post-implantation showed that complete closure was achieved in 65 patients (91.5%), and 6 patients (8.5%) had mild residual shunt. All patients (100%) had complete closure at 30 days of follow-up. The results of this study showed that the Occlutech PDA occluder device is safe and effective in the closure of PDA. As the pulmonary artery side of the device is wider than the aortic side, protrusion toward the aortic side and embolization are prevented, but there is residual shunt in the early period, although this residual shunt disappeared after a few months.
Organizational "Failure" and Institutional Pluralism: A Case Study of an Urban School Closure
ERIC Educational Resources Information Center
Deeds, Vontrese; Pattillo, Mary
2015-01-01
We use the framework of institutional pluralism to provide new insights into a controversial process of market-based reform-school closures. School closure is a shock that highlights the dynamics and definitions of failure and surfaces values and meanings that might otherwise be hidden from consideration. Using qualitative data from a closing…
ERIC Educational Resources Information Center
Blau, Gary
2007-01-01
This study partially tested a recent process model for understanding victim responses to worksite/function closure (W/FC) proposed by Blau [Blau, G. (2006). A process model for understanding victim responses to worksite/function closure. "Human Resource Management Review," 16, 12-28], in a pharmaceutical manufacturing site. Central to the model…
Lower early postnatal oxygen saturation target and risk of ductus arteriosus closure failure.
Inomata, Kei; Taniguchi, Shinji; Yonemoto, Hiroki; Inoue, Takeshi; Kawase, Akihiko; Kondo, Yuichi
2016-11-01
Early postnatal hyperoxia is a major risk factor for retinopathy of prematurity (ROP) in extremely premature infants. To reduce the occurrence of ROP, we adopted a lower early postnatal oxygen saturation (SpO 2 ) target range (85-92%) from April 2011. Lower SpO 2 target range, however, may lead to hypoxemia and an increase in the risk of ductus arteriosus (DA) closure failure. The aim of this study was therefore to determine whether a lower SpO 2 target range, during the early postnatal stage, increases the risk of DA closure failure. Infants born at <28 weeks' gestation were enrolled in this study. Oxygen saturation target range during the first postnatal 72 h was 84-100% in study period 1 and 85-92% in period 2. Eighty-two infants were included in period 1, and 61 were included in period 2. The lower oxygen saturation target range increased the occurrence of hypoxemia during the first postnatal 72 h. Prevalence of DA closure failure in period 2 (21%) was significantly higher than that in period 1 (1%). On multivariate logistic regression analysis, the lower oxygen saturation target range was an independent risk factor for DA closure failure. Lower early postnatal oxygen saturation target range increases the risk of DA closure failure. © 2016 Japan Pediatric Society.
40 CFR 265.310 - Closure and post-closure care.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 27 2013-07-01 2013-07-01 false Closure and post-closure care. 265.310... DISPOSAL FACILITIES Landfills § 265.310 Closure and post-closure care. (a) At final closure of the landfill... subsoils present. (b) After final closure, the owner or operator must comply with all post-closure...
40 CFR 265.310 - Closure and post-closure care.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 27 2012-07-01 2012-07-01 false Closure and post-closure care. 265.310... DISPOSAL FACILITIES Landfills § 265.310 Closure and post-closure care. (a) At final closure of the landfill... subsoils present. (b) After final closure, the owner or operator must comply with all post-closure...
40 CFR 265.310 - Closure and post-closure care.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 26 2014-07-01 2014-07-01 false Closure and post-closure care. 265.310... DISPOSAL FACILITIES Landfills § 265.310 Closure and post-closure care. (a) At final closure of the landfill... subsoils present. (b) After final closure, the owner or operator must comply with all post-closure...
Baskaran, Mani; Ho, Sue-Wei; Tun, Tin A; How, Alicia C; Perera, Shamira A; Friedman, David S; Aung, Tin
2013-11-01
To evaluate the diagnostic performance of the iris-trabecular contact (ITC) index, a measure of the degree of angle-closure, using swept-source optical coherence tomography (SSOCT, CASIA SS-1000, Tomey Corporation, Nagoya, Japan) in comparison with gonioscopy. Prospective observational study. A total of 108 normal subjects and 32 subjects with angle-closure. The SSOCT 3-dimensional angle scans, which obtain radial scans for the entire circumference of the angle, were performed under dark conditions and analyzed using customized software by a single examiner masked to the subjects' clinical details. The ITC index was calculated as a percentage of the angle that was closed on SSOCT images. First-order agreement coefficient (AC1) statistics and area under the receiver operating characteristic curve (AUC) analyses were performed for angle-closure on the basis of the ITC index in comparison with gonioscopy. Angle-closure on gonioscopy was defined as nonvisibility of posterior trabecular meshwork for at least 2 quadrants. Agreement of the ITC index with gonioscopically defined angle-closure was assessed using the AC1 statistic. Study subjects were predominantly Chinese (95.7%) and female (70.7%), with a mean age of 59.2 (standard deviation, 8.9) years. The median ITC index was 15.24% for gonioscopically open-angle eyes (n = 108) and 48.5% for closed-angle eyes (n = 32) (P = 0.0001). The agreement for angle-closure based on ITC index cutoffs (>35% and ≥50%) and gonioscopic angle-closure was 0.699 and 0.718, respectively. The AUC for angle-closure detection using the ITC index was 0.83 (95% confidence interval, 0.76-0.89), with an ITC index >35% having a sensitivity of 71.9% and specificity of 84.3%. The ITC index is a summary measure of the circumferential extent of angle-closure as imaged with SSOCT. The index had moderate agreement and good diagnostic performance for angle-closure with gonioscopy as the reference standard. Copyright © 2013 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.
Aerosol optical depth in a western Mediterranean site: An assessment of different methods
NASA Astrophysics Data System (ADS)
Sanchez-Romero, A.; González, J. A.; Calbó, J.; Sanchez-Lorenzo, A.; Michalsky, J.
2016-06-01
Column aerosol optical properties were derived from multifilter rotating shadowing radiometer (MFRSR) observations carried out at Girona (northeast Spain) from June 2012 to June 2014. We used a technique that allows estimating simultaneously aerosol optical depth (AOD) and Ångström exponent (AE) at high time-resolution. For the period studied, mean AOD at 500 nm was 0.14, with a noticeable seasonal pattern, i.e. maximum in summer and minimum in winter. Mean AE from 500 to 870 nm was 1.2 with a strong day-to-day variation and slightly higher values in summer. So, the summer increase in AOD seems to be linked with an enhancement in the number of fine particles. A radiative closure experiment, using the SMARTS2 model, was performed to confirm that the MFRSR-retrieved aerosol optical properties appropriately represent the continuously varying atmospheric conditions in Girona. Thus, the calculated broadband values of the direct flux show a mean absolute difference of less than 5.9 W m- 2 (0.77%) and R = 0.99 when compared to the observed fluxes. The sensitivity of the achieved closure to uncertainties in AOD and AE was also examined. We use this MFRSR-based dataset as a reference for other ground-based and satellite measurements that might be used to assess the aerosol properties at this site. First, we used observations obtained from a 100 km away AERONET station; despite a general similar behavior when compared with the in-situ MFRSR observations, certain discrepancies for AOD estimates in the different channels (R < 0.84 and slope < 1) appear. Second, AOD products from MISR and MODIS satellite observations were compared with our ground-based retrievals. Reasonable agreements are found for the MISR product (R = 0.92), with somewhat poorer agreement for the MODIS product (R = 0.70). Finally, we apply all these methods to study in detail the aerosol properties during two singular aerosol events related to a forest fire and a desert dust intrusion.
Şükür, Erhan; Öztürkmen, Yusuf; Akman, Yunus Emre; Senel, Ahmet; Azboy, İbrahim
2016-12-01
There is no consensus on the position of the knee joint while performing wound closure after total knee arthroplasty (TKA). Further, there are no studies focusing on the association between early functional outcomes and different wound closure strategies. Therefore, we investigated the effects of tourniquet and knee position during wound closure on early recovery of range of motion (ROM) after primary TKA. To our knowledge, this is the first study to evaluate the influence of both tourniquet and knee position during wound closure in primary TKA. One hundred-twenty eligible patients were consecutively enrolled in this study and randomly divided into four groups according to wound closure strategy. Wound closure was either performed with the knee in flexion at 90° or in full extension, with the combination of an inflated or deflated tourniquet. Visual analogue score (VAS), knee ROM, ROM recovery, knee society score (KSS), and wound complications were evaluated in the early postoperative period. After the first postoperative week, ROM recovery in the group with knee in extension and inflated tourniquet was significantly lesser than the two groups with deflated tourniquets. Between the first and fourth postoperative weeks, ROM recovery in the group with knee inflection and deflated tourniquet was significantly higher than the two groups with knee in extension. After the first postoperative week, the visual analog score (VAS) for pain in the group with knee inflection and deflated tourniquet was significantly lesser than the two groups with inflated tourniquets. The differences in the outcomes between the four groups were not significant after the fourth postoperative week. The incidence of wound complications and KSS were not significantly different between the four groups. Following TKA, wound closure with the knee in flexion and after deflating the tourniquet significantly decreased postoperative pain and promoted the recovery of ROM in the early postoperative period.
Cranial Suture Closure in Domestic Dog Breeds and Its Relationships to Skull Morphology.
Geiger, Madeleine; Haussman, Sinah
2016-04-01
Bulldog-type brachycephalic domestic dog breeds are characterized by a relatively short and broad skull with a dorsally rotated rostrum (airorhynchy). Not much is known about the association between a bulldog-type skull conformation and peculiar patterns of suture and synchondrosis closure in domestic dogs. In this study, we aim to explore breed-specific patterns of cranial suture and synchondrosis closure in relation to the prebasial angle (proxy for airorhynchy and thus bulldog-type skull conformation) in domestic dogs. For this purpose, we coded closure of 18 sutures and synchondroses in 26 wolves, that is, the wild ancestor of all domestic dogs, and 134 domestic dogs comprising 11 breeds. Comparisons of the relative amount of closing and closed sutures and synchondroses (closure scores) in adult individuals showed that bulldog-type breeds have significantly higher closure scores than non-bulldog-type breeds and that domestic dogs have significantly higher closure scores than the wolf. We further found that the prebasial angle is significantly positively correlated with the amount of closure of the basispheno-presphenoid synchondrosis and sutures of the nose (premaxillo-nasal and maxillo-nasal) and the palate (premaxillo-maxillary and interpalatine). Our results show that there is a correlation between patterns of suture and synchondrosis closure and skull shape in domestic dogs, although the causal relationships remain elusive. © 2016 Wiley Periodicals, Inc.
Shafi, Nabil A; Singh, Gagan D; Smith, Thomas W; Rogers, Jason H
2018-05-01
To describe a novel balloon sizing technique used during adult transcatheter patent ductus arteriosus (PDA) closure. In addition, to determine the clinical and procedural outcomes in six patients who underwent PDA balloon sizing with subsequent deployment of a PDA occluder device. Transcatheter PDA closure in adults has excellent safety and procedural outcomes. However, PDA sizing in adults can be challenging due to variable defect size, high flow state, or anatomical complexity. We describe a series of six cases where the balloon- pull through technique was successfully performed for PDA sizing prior to transcatheter closure. Consecutive adult patients undergoing adult PDA closure at our institution were studied retrospectively. A partially inflated sizing balloon was pulled through the defect from the aorta into the pulmonary artery and the balloon waist diameter was measured. Procedural success and clinical outcomes were obtained. Six adult patients underwent successful balloon pull-through technique for PDA sizing during transcatheter PDA closure, since conventional angiography often gave suboptimal opacification of the defect. All PDAs were treated with closure devices based on balloon PDA sizing with complete closure and no complications. In three patients that underwent preprocedure computed tomography, the balloon size matched the CT derived measurements. The balloon pull-through technique for PDA sizing is a safe and accurate sizing modality in adults undergoing transcatheter PDA closure. © 2017 Wiley Periodicals, Inc.
Mirzada, Naqibullah; Ladenvall, Per; Hansson, Per-Olof; Eriksson, Peter; Taft, Charles; Dellborg, Mikael
2018-04-15
Despite the widespread use of percutaneous closure of patent foramen ovale (PFO) in patients after a cryptogenic stroke, little is known about its impact on health-related quality of life (HRQoL). The aim of this study was to assess HRQoL in these patients compared to PFO patients not considered candidates for percutaneous closure, and to a normal population. A total of 402 patients with cryptogenic stroke or transient ischaemic attack (TIA) who had been referred to our center for PFO closure were invited to a long-term clinical follow-up (mean follow-up 5.5 years; range 3-13 years). HRQoL was assessed using the SF-36 Health Survey and data were compared with an age- and gender-matched reference group from the Swedish SF-36 normative database. Fifteen patients had died and 43 did not answer the SF-36. Of the remaining 344 patients, 208 had undergone PFO closure, and 136 had not. The closure group and reference group reported similar HRQoL levels. However, the non-closure group showed significantly lower HRQoL in role limitation - physical, vitality, general health, mental health (p < 0.05) and social functioning (p = 0.05) than the reference group and also had significantly lower scores than the closure group, correcting for age differences, on physical functioning, role limitation - physical, vitality and general health (p < 0.05). Non-closure patients had lower HRQoL than their counterparts in the normal population and the closure group. Percutaneous PFO closure is associated with a favorable quality of life. Copyright © 2018 Elsevier B.V. All rights reserved.
40 CFR 264.228 - Closure and post-closure care.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Closure and post-closure care. 264.228... Surface Impoundments § 264.228 Closure and post-closure care. (a) At closure, the owner or operator must... materials are left in place at final closure, the owner or operator must comply with all post-closure...
40 CFR 264.228 - Closure and post-closure care.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 27 2013-07-01 2013-07-01 false Closure and post-closure care. 264.228... Surface Impoundments § 264.228 Closure and post-closure care. (a) At closure, the owner or operator must... materials are left in place at final closure, the owner or operator must comply with all post-closure...
40 CFR 264.228 - Closure and post-closure care.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 27 2012-07-01 2012-07-01 false Closure and post-closure care. 264.228... Surface Impoundments § 264.228 Closure and post-closure care. (a) At closure, the owner or operator must... materials are left in place at final closure, the owner or operator must comply with all post-closure...
40 CFR 264.228 - Closure and post-closure care.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 26 2011-07-01 2011-07-01 false Closure and post-closure care. 264.228... Surface Impoundments § 264.228 Closure and post-closure care. (a) At closure, the owner or operator must... materials are left in place at final closure, the owner or operator must comply with all post-closure...
40 CFR 264.228 - Closure and post-closure care.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 26 2014-07-01 2014-07-01 false Closure and post-closure care. 264.228... Surface Impoundments § 264.228 Closure and post-closure care. (a) At closure, the owner or operator must... materials are left in place at final closure, the owner or operator must comply with all post-closure...
2014-01-01
Background Primary perineal wound closure after conventional abdominoperineal resection (cAPR) for rectal cancer has been the standard of care for many years. Since the introduction of neo-adjuvant radiotherapy and the extralevator APR (eAPR), oncological outcome has been improved, but at the cost of increased rates of perineal wound healing problems and perineal hernia. This has progressively increased the use of biological meshes, although not supported by sufficient evidence. The aim of this study is to determine the effectiveness of pelvic floor reconstruction using a biological mesh after standardized eAPR with neo-adjuvant (chemo)radiotherapy compared to primary perineal wound closure. Methods/Design In this multicentre randomized controlled trial, patients with a clinical diagnosis of primary rectal cancer who are scheduled for eAPR after neo-adjuvant (chemo)radiotherapy will be considered eligible. Exclusion criteria are prior radiotherapy, sacral resection above S4/S5, allergy to pig products or polysorbate, collagen disorders, and severe systemic diseases affecting wound healing, except for diabetes. After informed consent, 104 patients will be randomized between standard care using primary wound closure of the perineum and the experimental arm consisting of suturing a biological mesh derived from porcine dermis in the pelvic floor defect, followed by perineal closure similar to the control arm. Patients will be followed for one year after the intervention and outcome assessors and patients will be blinded for the study treatment. The primary endpoint is the percentage of uncomplicated perineal wound healing, defined as a Southampton wound score of less than II on day 30. Secondary endpoints are hospital stay, incidence of perineal hernia, quality of life, and costs. Discussion The BIOPEX-study is the first randomized controlled multicentre study to determine the additive value of using a biological mesh for perineal wound closure after eAPR with neo-adjuvant radiotherapy compared to primary perineal wound closure with regard to perineal wound healing and the occurrence of perineal hernia. Trail registration number NCT01927497 (Clinicaltrial.gov). PMID:25163547
Rosser, Julie; Brounts, Sabrina; Slone, Don; Lynch, Tim; Livesey, Michael; Hughes, Faith; Clark, Carol
2012-01-01
Our objective was to compare survival and complication rates of horses undergoing pelvic flexure enterotomy closure with a TA-90 stapler to those with hand-sewn closure. Medical records of horses undergoing pelvic flexure enterotomy between 2001 and 2008 were reviewed. History, clinical signs, surgical findings, surgical techniques, and post-operative complications were recorded. Long-term outcome was established by telephone questionnaire. Of 84 pelvic flexure enterotomies performed, 70 were stapled and 14 were hand-sewn. Seventy-seven horses survived to discharge (91.7%). There were no significant associations between survival and closure technique (P = 0.69). Follow-up was available for 54 horses; 50 survived long-term (93.0%). No statistical significance was identified between long-term survival and closure method (P = 0.39). Forty horses went on to athletic performance (80.0%). TA-90 stapled closure of pelvic flexure enterotomies is a safe technique resulting in survival and complication rates equivalent to those of hand-sewn closure. PMID:23204584
Closure behavior of spherical void in slab during hot rolling process
NASA Astrophysics Data System (ADS)
Cheng, Rong; Zhang, Jiongming; Wang, Bo
2018-04-01
The mechanical properties of steels are heavily deteriorated by voids. The influence of voids on the product quality should be eliminated through rolling processes. The study on the void closure during hot rolling processes is necessary. In present work, the closure behavior of voids at the center of a slab at 800 °C during hot rolling processes has been simulated with a 3D finite element model. The shape of the void and the plastic strain distribution of the slab are obtained by this model. The void decreases along the slab thickness direction and spreads along the rolling direction but hardly changes along the strip width direction. The relationship between closure behavior of voids and the plastic strain at the center of the slab is analyzed. The effects of rolling reduction, slab thickness and roller diameter on the closure behavior of voids are discussed. The larger reduction, thinner slab and larger roller diameter all improve the closure of voids during hot rolling processes. Experimental results of the closure behavior of a void in the slab during hot rolling process mostly agree with the simulation results..
Observations of turbulence in a partially stratified estuary
Stagey, M.T.; Monismith, Stephen G.; Burau, J.R.
1999-01-01
The authors present a field study of estuarine turbulence in which profiles of Reynolds stresses were directly measured using an ADCP throughout a 25-h tidal day. The dataset that is discussed quantifies turbulent mixing for a water column in northern San Francisco Bay that experiences a sequence of states that includes a weak ebb and flood that are stratified, followed by a strong, and eventually unstratified, ebb and flood. These measurements show that energetic turbulence is confined to a bottom mixed layer by the overlying stratification. Examination of individual Reynolds stress profiles along with profiles of Richardson number and turbulent Froude number shows that the water column can be divided into regions based on the relative importance of buoyancy effects. Using the measured turbulence production rate P, the dissipation rate e. is estimated. The observed turbulence had values of e/vN2 > 20 all of the time and e/vN2 > 200 most of the time, suggesting that the observed motions were buoyancy affected turbulence rather than internal waves. However, at times, turbulent Froude numbers in much of the upper-water column were less than one, indicating important stratification effects. Taken as a whole, the data show that stratification affects the turbulent velocity variance q2 most severely; that is, observed reductions in u'w' are largely associated with small values of q2 rather than with a dramatic reduction in the efficiency with which turbulent motions produce momentum fluxes. Finally, the dataset is compared to predictions made using the popular Mellor-Yamada level 2.5 closure. These comparisons show that the model tends to underestimate the turbulent kinetic energy in regions of strong stratification where the turbulence is strongly inhomogeneous and to overestimate the turbulent kinetic energy in weakly stratified regions. The length scale does not appear to compensate for these errors, and, as a result, similar errors are seen in the eddy viscosity predictions. It is hypothesized that the underestimation of q2 is due to an inaccurate parameterization of turbulence self-transport from the near-bed region to the overlying stratification. ?? 1999 American Meteorological Society.
Primary closure after carotid endarterectomy is not inferior to other closure techniques.
Avgerinos, Efthymios D; Chaer, Rabih A; Naddaf, Abdallah; El-Shazly, Omar M; Marone, Luke; Makaroun, Michel S
2016-09-01
Primary closure after carotid endarterectomy (CEA) has been much maligned as an inferior technique with worse outcomes than in patch closure. Our purpose was to compare perioperative and long-term results of different CEA closure techniques in a large institutional experience. A consecutive cohort of CEAs between January 1, 2000, and December 31, 2010, was retrospectively analyzed. Closure technique was used to divide patients into three groups: primary longitudinal arteriotomy closure (PRC), patch closure (PAC), and eversion closure (EVC). End points were perioperative events, long-term strokes, and restenosis ≥70%. Multivariate regression models were used to assess the effect of baseline predictors. There were 1737 CEA cases (bilateral, 143; mean age, 71.4 ± 9.3 years; 56.2% men; 35.3% symptomatic) performed during the study period with a mean clinical follow-up of 49.8 ± 36.4 months (range, 0-155 months). More men had primary closure, but other demographic and baseline symptoms were similar between groups. Half the patients had PAC, with the rest evenly distributed between PRC and EVC. The rate of nerve injury was 2.7%, the rate of reintervention for hematoma was 1.5%, and the length of hospital stay was 2.4 ± 3.0 days, with no significant differences among groups. The combined stroke and death rate was 2.5% overall and 3.9% and 1.7% in the symptomatic and asymptomatic cohort, respectively. Stroke and death rates were similar between groups: PRC, 11 (2.7%); PAC, 19 (2.2%); EVC, 13 (2.9%). Multivariate analysis showed baseline symptomatic disease (odds ratio, 2.4; P = .007) and heart failure (odds ratio, 3.1; P = .003) as predictors of perioperative stroke and death, but not the type of closure. Cox regression analysis demonstrated, among other risk factors, no statin use (hazard ratio, 2.1; P = .008) as a predictor of ipsilateral stroke and severe (glomerular filtration rate <30 mL/min/1.73 m(2)) renal insufficiency (hazard ratio, 2.6; P = .032) as the only predictor of restenosis ≥70%. Type of closure did not have any predictive value. In our study, baseline risk factors and statin use, but not the type of closure, affect perioperative and long-term outcomes after CEA. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.
Use of adhesive surgical tape with the absorbable continuous subcuticular suture.
Kolt, Jeremy D
2003-08-01
The absorbable continuous subcuticular suture is frequently used to close surgical incisions where the aim is healing by primary intention. A form of adhesive surgical tape is commonly also placed over the wound but this combination closure seems to have its development based on anecdotal, rather than experimental evidence. The present study reviews the scientific literature on the development of sutureless wound closure and presents the current evidence for the use of combination wound closure. Review was undertaken of the medical literature using the PubMed Internet database and cross-referencing major -articles on the subject. The following combinations of key words were searched: skin closure, wound closure, suture technique, sutureless, adhesive tape, op-site, staples, subcuticular suture, complication, infection and scars. Taped closure alone has advantages of lower wound infection rates and greater wound tensile strength, but disadvantages of epidermal reaction, skin edge inversion, doubtful safety and time required for meticulous surgical technique. The use of the continuous absorbable subcuticular suture allows accurate skin edge approximation, which increases the safety margin. The combination closure has a slightly superior cosmetic result to sutureless techniques but no study has been performed to compare the results of combination subcuticular suture and tape, with tape or subcuticular suture alone. There is no evidence in the scientific literature to justify or support the practice of closing a surgical wound with both subcuticular suture and adhesive surgical tape.
Venturini, Joseph M; Retzer, Elizabeth M; Estrada, J Raider; Mediratta, Anuj; Friant, Janet; Nathan, Sandeep; Paul, Jonathan D; Blair, John; Lang, Roberto M; Shah, Atman P
2016-10-01
Patent foramen ovale (PFO) has been linked to cryptogenic stroke, and closure has been reported to improve clinical outcomes. However, there are no clear guidelines to direct device sizing. This study sought to use patient characteristics and echocardiographic findings to create a prediction score for device sizing. This was a retrospective review of patients undergoing percutaneous PFO closure at our institution between July 2010 and December 2014. Demographic and clinical characteristics were recorded, and all pre- and intraprocedural echocardiography results were evaluated. Thirty-six patients underwent percutaneous PFO closure during the study period. All procedures were performed using an Amplatzer Septal Occluder "Cribriform" (ASOC) device in one of three disc diameters: 25, 30, or 35 mm. Closure was indicated for cryptogenic stroke/transient ischemic attack in 75% of cases. Every case (100%) was successful with durable shunt correction at the 6-month follow-up without complications of erosion or device embolization. The presence of atrial septal aneurysm (ASA) ( p = 0.027) and PFO tunnel length >10 mm ( p = 0.038) were independently associated with increased device size. A scoring system of 1 point for male sex, 1 point for ASA, and 1 point for PFO tunnel >10 mm long was associated with the size of closure device implanted ( p = 0.006). A simple scoring system may be used to select an optimally sized device for percutaneous PFO closure using the ASOC device.
Hospital closure: Phoenix, Hydra or Titanic?
Dunne, T; Davis, S
1996-01-01
Very little has been published about the effects of hospital closure in terms of the service, financial or management issues of the process. Attempts through a case-study format to redress the balance and as such represents the reflections of practitioners who have recently undergone the experience of hospital closure and the often neglected issues arising both during and after the process.
Stapler suture of the pharynx after total laryngectomy.
Dedivitis, R A; Aires, F T; Pfuetzenreiter, E G; Castro, M A F; Guimarães, A V
2014-04-01
The use of a stapler for pharyngeal closure during total laryngectomy was first described in 1971. It provides rapid watertight closure without surgical field contamination. The objective of our study was to compare the incidence of pharyngocutaneous fistula after total laryngectomy with manual and mechanical closures of the pharynx. This was a non-randomised, prospective clinical study conducted at two tertiary medical centres from 1996 to 2011 including consecutive patients with laryngeal tumours who underwent total laryngectomy. We compared the incidence of pharyngocutaneous fistula between two groups of patients: in 20 patients, 75 mm linear stapler closure was applied, whereas in 67 patients a manual suture was used. Clinical data were compared between groups. The groups were statistically similar in terms of gender, age, diabetes mellitus, smoking and alcohol consumption and tumour site. The group of patients who underwent stapler-assisted pharyngeal closure had a higher number of patients with previous tracheotomy (p < 0.001) and previous chemoradiation (p < 0.001). The incidence of pharyngocutaneous fistula was 30% in the mechanical closure group and 20.9% in the manual suture group (p = 0.42). In conclusion the use of the stapler does not increase the rate of fistulae.
DEDIVITIS, R.A.; AIRES, F.T.; PFUETZENREITER, E.G.; CASTRO, M.A.F.; GUIMARÃES, A.V.
2014-01-01
SUMMARY The use of a stapler for pharyngeal closure during total laryngectomy was first described in 1971. It provides rapid watertight closure without surgical field contamination. The objective of our study was to compare the incidence of pharyngocutaneous fistula after total laryngectomy with manual and mechanical closures of the pharynx. This was a non-randomised, prospective clinical study conducted at two tertiary medical centres from 1996 to 2011 including consecutive patients with laryngeal tumours who underwent total laryngectomy. We compared the incidence of pharyngocutaneous fistula between two groups of patients: in 20 patients, 75 mm linear stapler closure was applied, whereas in 67 patients a manual suture was used. Clinical data were compared between groups. The groups were statistically similar in terms of gender, age, diabetes mellitus, smoking and alcohol consumption and tumour site. The group of patients who underwent stapler-assisted pharyngeal closure had a higher number of patients with previous tracheotomy (p < 0.001) and previous chemoradiation (p < 0.001). The incidence of pharyngocutaneous fistula was 30% in the mechanical closure group and 20.9% in the manual suture group (p = 0.42). In conclusion the use of the stapler does not increase the rate of fistulae. PMID:24843218
Maekawa, Satoshi; Nomura, Ryosuke; Murase, Takayuki; Ann, Yasuyoshi; Harada, Masaru
2015-02-01
A 5-7 day hospital stay is usually needed after endoscopic submucosal dissection (ESD) of gastric tumor because of the possibility of delayed perforation or bleeding. The aim of this study was to evaluate the efficacy of combined use of a single over-the-scope clip (OTSC) and through-the-scope clips (TTSCs) to achieve complete closure of artificial gastric ulcer after ESD. We prospectively studied 12 patients with early gastric cancer or gastric adenoma. We performed complete closure of post-ESD artificial gastric ulcer using a combination of a single OTSC and TTSCs. Mean size of post-ESD artificial ulcer was 54.6 mm. The mean operating time for the closure procedure was 15.2 min., and the success rate was 91.7 % (11/12). Patients who underwent complete closure of post-ESD artificial gastric ulcer could be discharged the day after ESD and the closing procedure. Complete closure of post-ESD artificial gastric ulcer using a combination of a single OTSC and TTSCs is useful for shortening the period of hospitalization and reducing treatment cost.
Norman, Noraina Hafizan; Worthington, Helen; Chadwick, Stephen Mark
2016-09-01
To compare the clinical performance of nickel titanium (NiTi) versus stainless steel (SS) springs during orthodontic space closure. Two-centre parallel group randomized clinical trial. Orthodontic Department University of Manchester Dental Hospital and Orthodontic Department Countess of Chester Hospital, United Kingdom. Forty orthodontic patients requiring fixed appliance treatment were enrolled, each being randomly allocated into either NiTi (n = 19) or SS groups (n = 21). Study models were constructed at the start of the space closure phase (T0) and following the completion of space closure (T1). The rate of space closure achieved for each patient was calculated by taking an average measurement from the tip of the canine to the mesiobuccal groove on the first permanent molar of each quadrant. The study was terminated early due to time constraints. Only 30 patients completed, 15 in each study group. There was no statistically significant difference between the amounts of space closed (mean difference 0.17 mm (95%CI -0.99 to 1.34; P = 0.76)). The mean rate of space closure for NiTi coil springs was 0.58 mm/4 weeks (SD 0.24) and 0.85 mm/4 weeks (SD 0.36) for the stainless steel springs. There was a statistically significant difference between the two groups (P = 0.024), in favour of the stainless steel springs, when the mean values per patient were compared. Our study shows that stainless steel springs are clinically effective; these springs produce as much space closure as their more expensive rivals, the NiTi springs.
Kawai, Manabu; Hirono, Seiko; Okada, Ken-Ichi; Sho, Masayuki; Nakajima, Yoshiyuki; Eguchi, Hidetoshi; Nagano, Hiroaki; Ikoma, Hisashi; Morimura, Ryou; Takeda, Yutaka; Nakahira, Shin; Suzumura, Kazuhiro; Fujimoto, Jiro; Yamaue, Hiroki
2016-07-01
The aim of this study was to evaluate in a multicenter randomized controlled trial (RCT) whether pancreaticojejunostomy (PJ) of pancreatic stump decreases the incidence of pancreatic fistula after distal pancreatectomy (DP) compared with stapler closure. Several studies reported that PJ of pancreatic stump reduces the incidence of pancreatic fistula after DP. However, no RCT has confirmed the efficacy of PJ of pancreatic stump. One hundred thirty-six patients scheduled for DP were enrolled in this study between June 2011 and March 2014 at 6 high-volume surgical centers in Japan. Enrolled patients were randomized to either stapler closure or PJ. The primary endpoint was the incidence of pancreatic fistula based on the International Study Group on Pancreatic Fistula criteria. This RCT was registered with ClinicalTrials.gov (NCT01384617). Sixty-one patients randomized to stapler and 62 patients randomized to PJ were analyzed by intention-to-treat. Pancreatic fistula occurred in 23 patients (37.7%) in the stapler closure group and 24 (38.7%) in the PJ group (P = 0.332) in intention-to-treat analysis. The incidence of clinically relevant pancreatic fistula (grade B or C) was 16.4% for stapler closure and 9.7% for PJ (P = 0.201). Mortality was zero in both groups. In a subgroup analysis for thickness of pancreas greater than 12 mm, the incidence of clinically relevant pancreatic fistula occurred in 22.2% of the patients in the stapler closure group and in 6.2% of the PJ group (P = 0.080). PJ of the pancreatic stump during DP does not reduce pancreatic fistula compared with stapler closure.
Kawai, Manabu; Hirono, Seiko; Okada, Ken-ichi; Sho, Masayuki; Nakajima, Yoshiyuki; Eguchi, Hidetoshi; Nagano, Hiroaki; Ikoma, Hisashi; Morimura, Ryou; Takeda, Yutaka; Nakahira, Shin; Suzumura, Kazuhiro; Fujimoto, Jiro; Yamaue, Hiroki
2016-01-01
Objectives: The aim of this study was to evaluate in a multicenter randomized controlled trial (RCT) whether pancreaticojejunostomy (PJ) of pancreatic stump decreases the incidence of pancreatic fistula after distal pancreatectomy (DP) compared with stapler closure. Background: Several studies reported that PJ of pancreatic stump reduces the incidence of pancreatic fistula after DP. However, no RCT has confirmed the efficacy of PJ of pancreatic stump. Methods: One hundred thirty-six patients scheduled for DP were enrolled in this study between June 2011 and March 2014 at 6 high-volume surgical centers in Japan. Enrolled patients were randomized to either stapler closure or PJ. The primary endpoint was the incidence of pancreatic fistula based on the International Study Group on Pancreatic Fistula criteria. This RCT was registered with ClinicalTrials.gov (NCT01384617). Results: Sixty-one patients randomized to stapler and 62 patients randomized to PJ were analyzed by intention-to-treat. Pancreatic fistula occurred in 23 patients (37.7%) in the stapler closure group and 24 (38.7%) in the PJ group (P = 0.332) in intention-to-treat analysis. The incidence of clinically relevant pancreatic fistula (grade B or C) was 16.4% for stapler closure and 9.7% for PJ (P = 0.201). Mortality was zero in both groups. In a subgroup analysis for thickness of pancreas greater than 12 mm, the incidence of clinically relevant pancreatic fistula occurred in 22.2% of the patients in the stapler closure group and in 6.2% of the PJ group (P = 0.080). Conclusions: PJ of the pancreatic stump during DP does not reduce pancreatic fistula compared with stapler closure. PMID:26473652
Kossowska, Małgorzata; Bar-Tal, Yoram
2013-11-01
In contrast to the ample research that shows a positive relationship between the need for closure (NFC) and heuristic information processing, this research examines the hypothesis that this relationship is moderated by the ability to achieve closure (AAC), that is, the ability to use information-processing strategies consistent with the level of NFC. Three different operationalizations of heuristic information processing were used: recall of information consistent with the impression (Study 1); pre-decisional information search (Study 2); and stereotypic impression formation (Study 3). The results of the studies showed that there were positive relationships between NFC and heuristic information processing when participants assessed themselves as being able to use cognitive strategies consistent with their level of NFC (high AAC). For individuals with low AAC, the relationships were negative. Our data show that motivation-cognition interactions influence the information-processing style. © 2012 The British Psychological Society.
Outcomes of mechanical stapling for postlaryngectomy open pharyngotomy closure.
Paddle, Paul; Husain, Inna; McHugh, Lauren; Franco, Ramon
2017-03-01
A total laryngectomy (TL) is performed as a primary or salvage therapy for laryngeal carcinoma. Pharyngotomy closure after TL is typically performed using manual sutures. Automatic stapling devices are routinely used in thoracoabdominal surgery, but have not been widely accepted for use in pharyngotomy closure. Previously described closed stapling techniques of pharyngeal closure do not allow direct evaluation of surgical margins and are limited to endolaryngeal disease. We describe an open technique for pharyngotomy closure using a mechanical stapling device. Retrospective review. A review was conducted of 16 total laryngectomies performed from May 2008 to August 2015 utilizing an Ethicon Endopath ETS Compact-Flex 45 stapler. Sixteen patients (15 male, one female), mean age 69 years, received open TL (14 salvage, two primary) with endostapler pharyngeal closure and primary tracheoesophageal puncture (TEP). Surgical time averaged 218 minutes. Median time to swallowing was 4 days (range, 2-240 days) and mean hospital stay 6 days (range, 3-10 days). Fistula incidence was 31% (5/16) overall and 36% (5/14) in the postradiation patients. Mechanical stapling is a simple method for postlaryngectomy open pharyngotomy closure. This technique allows evaluation of margins, easy primary TEP, and the opportunity for early swallowing and shorter hospital stays. In addition, it can be performed for closure of salvage laryngectomies with rates of fistula formation similar to that found in the literature using suture closure techniques. Future studies are necessary to compare oncological results and surgical complications between the open and closed stapling techniques and to traditional suture closure. 4 Laryngoscope, 127:605-610, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.
Bogni, Serge; Ortner, Maria-Anna; Vajtai, Istvan; Jost, Christian; Reinert, Michael; Dallemagne, Bernard; Frenz, Martin
2012-07-01
Complete closure of gastrotomy is the linchpin of safe natural orifice transgastric endoscopic surgery. To evaluate feasibility and efficacy of a new method of gastrotomy closure by using a sutureless laser tissue-soldering (LTS) technique in an ex vivo porcine stomach. In vitro experiment. Experimental laboratory. Histological analysis and internal and external liquid pressure with and without hydrochloric acid exposure were determined comparing gastrotomy closure with LTS and with hand-sewn surgical sutures. Comparison of LTS and hand-sewn surgical gastrotomy closure. The primary outcome parameter was the internal leak pressure. Secondary parameters were the difference between internal and external leak pressures, the impact of an acid environment on the device, histological changes, and feasibility of endoscopic placement. The internal liquid leak pressure after LTS was almost twice as high as after hand-sewn surgical closure (416 ± 53 mm Hg vs 229 ± 99 mm Hg; P = .01). The internal leak pressure (416 ± 53 mm Hg) after LTS was higher than the external leak pressure (154 ± 46 mm Hg; P < .0001). An acidic environment did not affect leak pressure after LTS. Endoscopic LTS closure was feasible in all experiments. Histopathology revealed only slight alterations beneath the soldering plug. In vitro experiments. Leak pressure after LTS closure of gastrotomy is higher than after hand-sewn surgical closure. LTS is a promising technique for closure of gastrotomies and iatrogenic perforations. Further experiments, in particular survival studies, are mandatory. Copyright © 2012 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.
Robotic laser tissue welding of sclera using chitosan films.
Garcia, Pablo; Mines, Michael J; Bower, Kraig S; Hill, J; Menon, J; Tremblay, Eric; Smith, Benjamin
2009-01-01
To demonstrate the feasibility of scleral wound closure using a novel adhesive made of chitosan film. Five-millimeter scleral lacerations were created in enucleated pig eyes. Casted chitosan films were sized to 7x7 mm patches. Lacerations were sealed with chitosan film alone (7 eyes) or chitosan film followed by laser irradiation using a near infrared laser (1,455 nm) at 350 mW for 6 minutes (7 eyes). Seven eyes were closed with 9-0 nylon suture for comparison (7 eyes). Outcome measures included watertight closure, closure time, and leak pressure. Leak pressure was measured with a pressure transducer attached to tubing continuously monitored intraocular pressure during saline infusion. Watertight closure testing was performed immediately following closure (n = 3 per group) and after 24 hours (n = 3 per group). One eye in each group was fixed in formalin for histology. All wounds were watertight for each closure method. Mean closure time with unlasered chitosan film was 2.24 minutes (range 1.80-3.26, 7 eyes) with a mean leak pressure of 303 mm Hg (range 217-364, 3 eyes). Mean closure time with lasered chitosan was 12.47 minutes (range 11.45-14.15, 7 eyes) with a mean leak pressure of 454.7 mm Hg (range 152-721, 3 eyes). Suture closure required a mean of 4.83 minutes (range 4.03-7.30, 7 eyes) and resulted in a mean leak pressure of 570.3 mm Hg (range 460-646, 3 eyes). Both lasered and unlasered chitosan eyes remained watertight after 24 hours. Histology revealed minimal laser tissue damage in lasered eyes. In this preliminary study chitosan film successfully closed scleral lacerations with and without the application of laser energy. While laser appears to strengthen the closure, it significantly increases the closure time. Chitosan based adhesives hold promise as a scleral wound closure technique.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ketusky, Edward; Blanton, Paul; Bobbitt, John H.
The Department of Energy, the Savannah River National Laboratory, several manufacturers of specification drums, and the United States Department of Transportation (DOT) are collaborating in the development of a guidance document for DOE contractors and vendors who wish to qualify containers to DOT 7A Type A requirements. Currently, the effort is focused on DOT 7A Type A 208-liter (55-gallons) drums with a standard 12-gauge bolted closure ring. The U.S. requirements, contained in Title 49, Part 178.350 “Specification 7A; general packaging, Type A specifies a competent authority review of the packaging is not required for the transport of (Class 7) radioactivemore » material containing less than Type A quantities of radioactive material. For Type AF drums, a 4 ft. regulatory free drop must be performed, such that the drum “suffers maximum damage.” Although the actual orientation is not defined by the specification, recent studies suggest that maximum damage would result from a shallow angle top impact, where kinetic energy is transferred to the lid, ultimately causing heavy damage to the lid, or even worse, causing the lid to come off. Since each vendor develops closure recommendations/procedures for the drums they manufacture, key parameters applied to drums during closing vary based on vendor. As part of the initial phase of the collaboration, the impact of the closure variants on the ability of the drum to suffer maximum damage is investigated. Specifically, closure testing is performed varying: 1) the amount of torque applied to the closure ring bolt; and, 2) stress relief protocol, including: a) weight of hammer; and, b) orientation that the hammer hits the closure ring. After closure, the amount of drum lid gasket contraction and the distance that the closure bolt moves through the closure ring is measured.« less
Interferometric Imaging Directly with Closure Phases and Closure Amplitudes
NASA Astrophysics Data System (ADS)
Chael, Andrew A.; Johnson, Michael D.; Bouman, Katherine L.; Blackburn, Lindy L.; Akiyama, Kazunori; Narayan, Ramesh
2018-04-01
Interferometric imaging now achieves angular resolutions as fine as ∼10 μas, probing scales that are inaccessible to single telescopes. Traditional synthesis imaging methods require calibrated visibilities; however, interferometric calibration is challenging, especially at high frequencies. Nevertheless, most studies present only a single image of their data after a process of “self-calibration,” an iterative procedure where the initial image and calibration assumptions can significantly influence the final image. We present a method for efficient interferometric imaging directly using only closure amplitudes and closure phases, which are immune to station-based calibration errors. Closure-only imaging provides results that are as noncommittal as possible and allows for reconstructing an image independently from separate amplitude and phase self-calibration. While closure-only imaging eliminates some image information (e.g., the total image flux density and the image centroid), this information can be recovered through a small number of additional constraints. We demonstrate that closure-only imaging can produce high-fidelity results, even for sparse arrays such as the Event Horizon Telescope, and that the resulting images are independent of the level of systematic amplitude error. We apply closure imaging to VLBA and ALMA data and show that it is capable of matching or exceeding the performance of traditional self-calibration and CLEAN for these data sets.
Wang, Zhongkai; Chen, Tao; Chen, Liang; Qin, Yongwen; Zhao, Xianxian
2016-01-01
Transcatheter closure is the usual treatment for patent ductus arteriosus (PDA), but its safety and efficacy have not been reported in adult PDA patients with severe mitral regurgitation. A retrospective study on 27 consecutive patients diagnosed with PDA and severe mitral regurgitation and treated using transcatheter closure between September 2010 and September 2012 at the Department of Cardiology of Changhai Hospital in Changhai, China. Left ventricular (LV) diastolic volume and function, pulmonary artery pressure, and instantaneous reverse-flow volume were examined by echocardiography before PDA closure, immediately after closure, and 1 year after closure. After the procedure, the LV diastolic volume (P<.05) and instantaneous reverse-flow volume (P<.001) were significantly decreased. There was no effect on the ejection fraction (P>.05). Pulmonary arterial systolic pressure was unchanged 1 year after closure (from 46.41 ± 19.92 mm Hg to 45.43 ± 13.64 mm Hg; P=.58). All procedures were uneventful and only mild complications occurred (hemolysis in 2 cases, subcutaneous hematoma in 4 cases, and fever in 2 cases). Transcatheter closure can decrease the LV volume and instantaneous reverse-flow volume in adult PDA patients with severe mitral regurgitation. This procedure is effective and has a good safety profile.
Manoj-Kumar, Mitta; Gowri-Sankar, Singaraju; Chaitanya, Nellore; Vivek-Reddy, Ganugapanta; Venkatesh, Nettam
2016-01-01
Background To evaluate the closure of midline diastema using the Neodymium-Iron-Boron magnets and to compare the treatment duration of midline diastemas with the use of magnets compared to regular orthodontic treatment. Material and Methods Thirty patients with age group 12 to 30 years with the midline diastema ranging from 0.5 to 3mm were selected. These patients were divided into two groups. Diastema closure in one group was accomplished by conventional method, in other group was done with Ne2Fe14B magnets. These magnets were fitted to the labial surfaces of the maxillary central incisors such a way that the opposite poles of the magnets face each other. At each appointment, study models and radiographs were taken for study subjects and the midline diastema was measured using digital vernier calipers on the study models obtained. Descriptive statistics carried out using Paired t-test. Results Subjects treated with Ne2Fe14B magnets showed a significant difference compared to fixed orthodontic appliance subjects with respect to time of closure, rate of space closure and incisal inclination. Significant difference between 2 groups with reduction of 64.6 days in time to diastema closure in subjects treated with Ne2Fe14B magnets (P<0.05). Conclusions Ne2Fe14B magnets more efficient in complete closure of mid line diastema in less duration of time. Key words:Midline diastema, Ne2Fe14B magnets, rare earth magnets, space closure. PMID:27034757
Reduction of the closure time of postoperative enterocutaneous fistulas with fibrin sealant
Avalos-González, Jorge; Portilla-deBuen, Eliseo; Leal-Cortés, Caridad Aurea; Orozco-Mosqueda, Abel; del Carmen Estrada-Aguilar, María; Velázquez-Ramírez, Gabriela Abigail; Ambriz-González, Gabriela; Fuentes-Orozco, Clotilde; Guzmán-Gurrola, Aldo Emmerson; González-Ojeda, Alejandro
2010-01-01
AIM: To assess whether the use of fibrin sealant shortens the closure time of postoperative enterocutaneous fistulas (ECFs). METHODS: The prospective case-control study included 70 patients with postoperative ECFs with an output of < 500 mL/d, a fistulous tract of > 2 cm and without any local complication. They were divided into study (n = 23) and control groups (n = 47). Esophageal, gastric and colocutaneous fistulas were monitored under endoscopic visualization, which also allowed fibrin glue application directly through the external hole. Outcome variables included closure time, time to resume oral feeding and morbidity related to nutritional support. RESULTS: There were no differences in mean age, fistula output, and follow-up. Closure-time for all patients of the study group was 12.5 ± 14.2 d and 32.5 ± 17.9 d for the control group (P < 0.001), and morbidity related to nutritional support was 8.6% and 42.5%, respectively (P < 0.01). In patients with colonic fistulas, complete closure occurred 23.5 ± 19.5 d after the first application of fibrin glue, and spontaneous closure was observed after 36.2 ± 22.8 d in the control group (P = 0.36). Recurrences were observed in 2 patients because of residual disease. One patient of each group died during follow-up as a consequence of septic complications related to parenteral nutrition. CONCLUSION: Closure time was significantly reduced with the use of fibrin sealant, and oral feeding was resumed faster. We suggest the use of fibrin sealant for the management of stable enterocutaneous fistulas. PMID:20533600
NASA Astrophysics Data System (ADS)
Bayer, S.; Wahle, R.; Brooks, D. A.; Brady, D. C.
2016-02-01
The giant sea scallop, Placopecten magellanicus, is a commercially valuable sedentary broadcast spawner that occupies offshore banks and coastal bays and estuaries in the Northwest Atlantic. Although area closures have helped repopulate depleted scallop populations, little is known about whether populations at densities that yield larvae supply local or distant populations. Surveying scallop populations in the Damariscotta River estuary in Maine during the 2013 and 2014 spawning seasons, and settling out spat bags to collect settling larvae along the gradient of the estuary, we were able to compare adult densities to newly settled juvenile (`spat') abundance. Using the location where we found a high density of adults, we incorporated previously published behavior, pelagic larval duration, wind and current data into a particle dispersal model within the estuary to determine likely sinks for larvae from the 2013 and 2014 spawning seasons. Preliminary model simulations demonstrate where in the estuary swimming is effective in affecting water column position for larvae, and that most larvae are retained much closer to the mouth of the estuary than previously expected. Combining larval dispersal modeling with empirical data on adult densities and spat settlement on the scale of an embayment or estuary may be helpful in determining sources, sinks and areas that are both sources and sinks for shellfish species that are endangered or economically critical. This may aid in determining small area closures or Marine Protected Areas along coastal regions in the Gulf of Maine and beyond.
Wu, Xiuwen; Ren, Jianan; Wang, Gefei; Wang, Jianzhong; Wang, Feng; Fan, Yueping; Li, Yuanxin; Han, Gang; Zhou, Yanbing; Song, Xiaofei; Quan, Bin; Yao, Min; Li, Jieshou
2015-10-07
The management of an enterocutaneous fistula poses a significant challenge to surgeons and is often associated with a costly hospital stay and long-term discomfort. The use of fibrin glue in the fistula tract has been shown to promote closure of low output enterocutaneous fistulas. Our previous nonrandomized study demonstrated that autologous platelet-rich fibrin glue treatment significantly decreased time to fistula closure and promoted closure rates. However, there are several limitations in the study, which may lead to bias in our conclusion. Thus, a multicenter, randomized, controlled clinical trial is required. The study is designed as a randomized, open-label, three-arm, multicenter study in nine Chinese academic hospitals for evaluating the efficacy and safety of fibrin glue for sealing low-output fistulas. An established number of 171 fistula patients will undergo prospective random assignment to autologous fibrin glue, commercial porcine fibrin sealants or drainage cessation (1:1:1). The primary endpoint is fistula closure time (defined as the interval between the day of enrollment and day of fistula closure) during the 14-day treatment period. To our knowledge, this is the first study to evaluate the safety and efficacy of both autologous and commercial fibrin glue sealing for patients with low-output volume fistulas. NCT01828892 . Registration date: April 2013.
40 CFR 265.228 - Closure and post-closure care.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 27 2012-07-01 2012-07-01 false Closure and post-closure care. 265.228... DISPOSAL FACILITIES Surface Impoundments § 265.228 Closure and post-closure care. (a) At closure, the owner... impoundment and provide post-closure care for a landfill under subpart G and § 265.310, including the...
40 CFR 265.228 - Closure and post-closure care.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 26 2011-07-01 2011-07-01 false Closure and post-closure care. 265.228... DISPOSAL FACILITIES Surface Impoundments § 265.228 Closure and post-closure care. (a) At closure, the owner... impoundment and provide post-closure care for a landfill under subpart G and § 265.310, including the...
Does patent foramen ovale closure have an anti-arrhythmic effect? A meta-analysis.
Jarral, Omar A; Saso, Srdjan; Vecht, Joshua A; Harling, Leanne; Rao, Christopher; Ahmed, Kamran; Gatzoulis, Michael A; Malik, Iqbal S; Athanasiou, Thanos
2011-11-17
Atrial tachyarrhythmias are associated with patent foramen ovale. The objective was to determine the anti-arrhythmic effect of patent foramen ovale closure on pre-existing atrial tachyarrhythmias. Medline, EMBASE, Cochrane Library, and Google Scholar databases were searched between 1967 and 2010. The search was expanded using the 'related articles' function and reference lists of key studies. All studies reporting pre- and post-closure incidence (or prevalence) of atrial tachyarrhythmia in the same patient population were included. Random and fixed effect meta-analyses were used to aggregate the data. Six studies were identified including 2570 patients who underwent percutaneous closure. Atrial fibrillation was in fact the only AT reported in all studies. Meta-analysis using a fixed effects model demonstrated a significant reduction in the prevalence of atrial fibrillation with an OR of 0.43 (95% CI 0.26-0.71). When using the random-effects model, OR was 0.44 (95% CI 0.18-1.04) with a statistically significant trend demonstrated (test for overall effect: Z=1.87, p=0.06). Closure of a patent foramen ovale may be associated with reduction in the prevalence of atrial fibrillation. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.
Forces Generated by Cell Intercalation Tow Epidermal Sheets in Mammalian Tissue Morphogenesis
Heller, Evan; Kumar, K. Vijay; Grill, Stephan W.; Fuchs, Elaine
2014-01-01
Summary While gastrulation movements offer mechanistic paradigms for how collective cellular movements shape developing embryos, far less is known about coordinated cellular movements that occur later in development. Studying eyelid closure, we explore a case where an epithelium locally reshapes, expands, and moves over another epithelium. Live imaging, gene targeting and cell cycle inhibitors reveal that closure does not require overlying periderm, proliferation or supracellular actin cable assembly. Laser ablation and quantitative analyses of tissue deformations further distinguish the mechanism from wound-repair and dorsal closure. Rather, cell intercalations parallel to the tissue front locally compress it perpendicularly, pulling the surrounding epidermis along the closure axis. Functional analyses in vivo show that the mechanism requires localized myosin-IIA and α5β1-fibronectin-mediated migration, and E-cadherin downregulation likely stimulated by Wnt signaling. These studies uncover a mode of epithelial closure in which forces generated by cell intercalation are leveraged to tow the surrounding tissue. PMID:24697897
Cystic Duct Closure by Sealing With Bipolar Electrocoagulation
Damgaard, B.; Jorgensen, L. N.; Larsen, S. S.; Kristiansen, V. B.
2010-01-01
Background: Cystic duct leakage after cholecystectomy is not uncommon and is a potentially serious complication. The aim of this study was to assess a bipolar sealing system (LigaSure®) for closure of the cystic duct. Methods: The records from consecutive laparoscopic cholecystectomies performed in 2 hospitals with closure of the cystic duct with LigaSure after informed consent were recorded and complications and morbidity registered. The records were compared with those of patients undergoing laparoscopic cholecystectomy with closure of the cystic duct with clips during the same period. Results: During the study period, 218 laparoscopic cholecystectomies were performed; 102 of these were performed with the LigaSure. One patient was excluded due to violation of the protocol. We experienced no cases of cystic duct leakage, but in one patient, bile leakage from the gallbladder bed was observed probably due to a small aberrant duct. Conclusion: The LigaSure system was safe and effective for closure and division of the cystic duct in laparoscopic cholecystectomy. PMID:20412641
DOE Office of Scientific and Technical Information (OSTI.GOV)
Harman-Ware, Anne E.; Davis, Mark F.; Peter, Gary F.
Terpenes can be used as renewable fuels and chemicals and quantifying their presence in biomass is becoming increasingly important. A novel method was developed to rapidly quantify total diterpenoid resin acids using pyrolysis-molecular beam mass spectrometry (py-MBMS). Pine sapling monoterpenes and diterpenoids were extracted from wood using a 1:1 (v/v) mixture of hexane and acetone and analyses were performed before and after extraction to determine the extraction efficiency of the solvent system. The resulting extract was analyzed for total diterpenoid content using py-MBMS and was combined with total monoterpene content that was determined using a low thermal mass modular acceleratedmore » column heater (LTM MACH) fast-GC/FID to measure the terpene content present in pine saplings. Oleoresin extruded from larger pine trees was used to validate mass balance closure of the terpene content in the extract solvent.« less
Harman-Ware, Anne E.; Davis, Mark F.; Peter, Gary F.; ...
2017-01-16
Terpenes can be used as renewable fuels and chemicals and quantifying their presence in biomass is becoming increasingly important. A novel method was developed to rapidly quantify total diterpenoid resin acids using pyrolysis-molecular beam mass spectrometry (py-MBMS). Pine sapling monoterpenes and diterpenoids were extracted from wood using a 1:1 (v/v) mixture of hexane and acetone and analyses were performed before and after extraction to determine the extraction efficiency of the solvent system. The resulting extract was analyzed for total diterpenoid content using py-MBMS and was combined with total monoterpene content that was determined using a low thermal mass modular acceleratedmore » column heater (LTM MACH) fast-GC/FID to measure the terpene content present in pine saplings. Oleoresin extruded from larger pine trees was used to validate mass balance closure of the terpene content in the extract solvent.« less
Lu, Xujin; Lloyd, David K; Klohr, Steven E
2016-01-01
A feasibility study was conducted for a sensitive and robust dye immersion method for the measurement of container closure integrity of unopened prefilled syringes using fluorescence spectrophotometry as the detection method. A Varian Cary Eclipse spectrofluorometer was used with a custom-made sample holder to position the intact syringe in the sample compartment for fluorescence measurements. Methylene blue solution was initially evaluated as the fluorophore in a syringe with excitation at 607 nm and emission at 682 nm, which generated a limit of detection of 0.05 μg/mL. Further studies were conducted using rhodamine 123, a dye with stronger fluorescence. Using 480 nm excitation and 525 nm emission, the dye in the syringe could be easily detected at levels as low as 0.001 μg/mL. The relative standard deviation for 10 measurements of a sample of 0.005 μg/mL (with repositioning of the syringe after each measurement) was less than 1.1%. A number of operational parameters were optimized, including the photomultiplier tube voltage, excitation, and emission slit widths. The specificity of the testing was challenged by using marketed drug products and a protein sample, which showed no interference to the rhodamine detection. Results obtained from this study demonstrated that using rhodamine 123 for container closure integrity testing with in-situ (in-syringe) fluorescence measurements significantly enhanced the sensitivity and robustness of the testing and effectively overcame limitations of the traditional methylene blue method with visual or UV-visible absorption detection. Ensuring container closure integrity of injectable pharmaceutical products is necessary to maintain quality throughout the shelf life of a sterile drug product. Container closure integrity testing has routinely been used to evaluate closure integrity during product development and production line qualification of prefilled syringes, vials, and devices. However, container closure integrity testing has recently gained industry attention due to increased regulatory agency scrutiny regarding the analytical rigor of container closure integrity testing methods and expectations to use container closure integrity testing in lieu of sterility tests in stability programs. Methylene blue dye is often used for dye ingress testing of container closure integrity, but we found it unsuitable for reliable detection of small breaches in prefilled syringes of drug product. This work describes the suitability and advantages of using a fluorescent dye and spectroscopic detection for a robust, sensitive, and quality control-friendly container closure integrity testing method for prefilled syringes. © PDA, Inc. 2016.
Dariel, Anne; Poocharoen, Wannisa; de Silva, Nicole; Pleasants, Hazel; Gerstle, Justin Ted
2015-02-01
Nonsurgical closure after primary silo placement, secondary plastic closure (SPC), has been used as an alternative to secondary surgical closure (SSC) in gastroschisis. The benefits described were closure without formal surgical procedure, cosmetic aspect, and minimization of intra-abdominal pressures. This study compared requirements for mechanical ventilation and general anesthesia, nutritional care, and outcomes between SPC and SSC. We included patients with primary staged-silo reduction with a 1-year minimum follow-up. SPC was performed at bedside with sedation using a nonadherent dressing. SSC was performed in operating room under general anesthesia using standard surgical techniques. This retrospective study included 64 patients, 23 SPC and 41 SSC. The characteristics of the two groups were comparable. Mechanical ventilation was used for 15 SPC and 41 SSC (p=0.0001) with a comparable median duration (5.5 and 6.0 days, not significant [NS]). General anesthesia was required for 9 SPC and 41 SSC (p<0.0001). Complications included one SPC and six SSC with necrotizing enterocolitis, zero SPC and four SSC with intestinal atresia, two SPC and four SSC with small bowel obstruction, zero SPC and one SSC with abdominal compartment syndrome resulting in a short bowel syndrome (NS). Median duration of parenteral nutrition (30 and 27 days), time to first feeds (14 and 14 days), time at or above minimal enteral feeding (22 and 17 days), time to full feeds (31 and 28 days), length of stay (LOS) in neonatal intensive care unit (24 and 23.5 days) and overall hospital LOS (37 and 36 days) were not statistically different between SPC and SSC patients without complications, respectively. These data were comparable for SPC and SSC patients with complications. Five SPC and six SSC developed an umbilical hernia (NS); two patients in each group required a surgical repair (NS). Plastic closure of gastroschisis after primary silo reduction is simple, safe, reproducible, and associated with a significant lower incidence of mechanical ventilation. Nutritional management and length of hospital stay were similar to conventional surgical closure for patients. Plastic closure allows nonoperative management without general anesthesia at patient's bedside, in comparison with surgical closure that must be performed under general anesthesia in the operating room. Plastic closure does not appear to be associated with more umbilical hernias in this retrospective study. Georg Thieme Verlag KG Stuttgart · New York.
40 CFR 264.146 - Use of a mechanism for financial assurance of both closure and post-closure care.
Code of Federal Regulations, 2013 CFR
2013-07-01
... assurance of both closure and post-closure care. 264.146 Section 264.146 Protection of Environment... mechanism for financial assurance of both closure and post-closure care. An owner or operator may satisfy the requirements for financial assurance for both closure and post-closure care for one or more...
Simonetti, Andrea; Amari, Filippo
2015-01-01
In reaction to the limitations of the traditional sterility test methods, in 2008, the U.S. Food and Drug Administration issued the guidance "Container and Closure System Integrity Testing in Lieu of Sterility Testing as a Component of the Stability Protocol for Sterile Products" encouraging sterile drug manufacturers to use properly validated physical methods, apart from conventional microbial challenge testing, to confirm container closure integrity as part of the stability protocol. The case study presented in this article investigated the capability of four container closure integrity testing methods to detect simulated defects of different sizes and types on glass syringes, prefilled both with drug product intended for parenteral administration and sterile water. The drug product was a flu vaccine (Agrippal, Novartis Vaccines, Siena, Italy). Vacuum decay, pharmacopoeial dye ingress test, Novartis specific dye ingress test, and high-voltage leak detection were, in succession, the methods involved in the comparative studies. The case study execution was preceded by the preparation of two independent sets of reference prefilled syringes, classified, respectively, as examples of conforming to closure integrity requirements (negative controls) and as defective (positive controls). Positive controls were, in turn, split in six groups, three of with holes laser-drilled through the prefilled syringe glass barrel, while the other three with capillary tubes embedded in the prefilled syringe plunger. These reference populations were then investigated by means of validated equipment used for container closure integrity testing of prefilled syringe commercial production; data were collected and analyzed to determine the detection rate and the percentage of false results. Results showed that the vacuum decay method had the highest performance in terms of detection sensitivity and also ensured the best reliability and repeatability of measurements. An innovative technical solution, preventing possible prefilled syringe plunger movement during container closure integrity testing execution, is presented as well. The growing need to meet sterile drug products' regulatory, quality, and safety expectations has progressively driven new developments and improvements both in container closure integrity testing methods and in the respective equipment, over the last years. Indeed, container closure integrity testing establishes the container closure system capability to provide required protection to the drug product and to demonstrate maintenance of product sterility over its shelf life. This article describes the development of four container closure integrity testing approaches for the evaluation of glass prefilled syringe closure integrity, including two destructive (pharmacopoeial and Novartis specific dye ingress test) and two non-destructive (vacuum decay and high-voltage leak detection) methods. The important finding from the validation of comparative studies was that the vacuum decay method resulted in the most effective, reliable and repeatable detection of defective samples, whether the defect was exposed to sterile water, to drug product, or to air. Complete sets of known defects were created for this purpose (5 μm, 10 μm, 20 μm certified leakages by laser drilled holes and capillary tubes). All investigations and studies were conducted at Bonfiglioli Engineering S.r.l. (Vigarano Pieve, Ferrara, Italy) and at Novartis Vaccines (Sovicille, Siena, Italy). © PDA, Inc. 2015.
Evaluation of a novel technique for wound closure using a barbed suture.
Murtha, Amy P; Kaplan, Andrew L; Paglia, Michael J; Mills, Benjie B; Feldstein, Michael L; Ruff, Gregory L
2006-05-01
Suture knots present several disadvantages in wound closure, because they are tedious to tie and place ischemic demands on tissue. Bulky knots may be a nidus for infection, and they may extrude through skin weeks after surgery. Needle manipulations during knot-tying predispose the surgeon to glove perforation. A barbed suture was developed that is self-anchoring, requiring no knots or slack management for wound closure. The elimination of knot tying may have advantages over conventional wound closure methods. This prospective, randomized, controlled trial was designed to show that the use of barbed suture in dermal closure of the Pfannenstiel incision during nonemergent cesarean delivery surgery produces scar cosmesis at 5 weeks that is no worse than that observed with conventional closure using 3-0 polydioxanone suture. Cosmesis was assessed by review of postoperative photographs by a blinded, independent plastic surgeon using the modified Hollander cosmesis score. Secondary endpoints included infection, dehiscence, pain, closure time, and other adverse events. The study enrolled 195 patients, of whom 188 were eligible for analysis. Cosmesis scores did not significantly differ between the barbed suture group and the control group. Rates of infection, dehiscence, and other adverse events did not significantly differ between the two groups. Closure time and pain scores were comparable between the groups. The barbed suture represents an innovative option for wound closure. With a cosmesis and safety profile that is similar to that of conventional suture technique, it avoids the drawbacks inherent to suture knots.
Muhammad, Yar; Gondal, Khalid Masood; Khan, Umair Ahmed
2016-08-01
To assess the efficacy of Bogota bag for closure of open abdominal wounds after laparotomy where the primary closure cannot be achieved and other closure techniques are not available. The descriptive study was conducted at Mayo Hospital, Lahore, Pakistan, from September 2011 to February2015, and comprised patients who underwent laparotomy and peritoneal cavities and who could not be closed primarily because of various reasons like traumatic loss and oedematous gut. They were managed with Bogota bag for abdominal closure. SPSS 18 was used for statistical analysis. Of the 55 patients, 37(67.27%) were male and 18(32.73%) were female. There was traumatic loss in 34(61.8%), oedematous gut and omentum in 15(27.27%) and gangrenous abdominal wall in 6(10.9%) patients. Bogota bag was applied in all (100%) of them. In 19(34.55%) patients, delayed primary closure was possible, so the Bogota was used temporarily. In 36(65.45%) cases managed with Bogota bag, healing occurred by granulation tissue or skin grafting/flaps were applied and these patients developed hernia. Five (9.09%) patients developed small bowel fistula which was managed conservatively. No patient developed complication due to exposure or abdominal compartment. There were 7(12.8%) postoperative deaths due to the disease process and were unrelated to the closure technique. Bogota bag was an effective means of closure of open abdominal wound and prevented the complications due to open abdominal wounds or closure under tension.
Hardman, John; Muzaffar, Jameel; Nankivell, Paul; Coulson, Chris
2015-06-01
To study the effectiveness of Type 1 tympanoplasty for chronic tympanic membrane perforations in the pediatric age group and to investigate factors influencing its success. Searches were conducted of the MEDLINE database and the Cochrane Database of Systematic Reviews using terms focused around tympanoplasty and children. Searches were performed on June 23, 2014 and limited to English language entries since January 1, 1997. Studies reporting tympanoplasty closure rates in children 18 years and younger, with a minimum follow-up of 6 months, were included. Studies focusing on more advanced forms of tympanoplasty and revision surgery were excluded. Five hundred sixty-four articles were screened identifying 2,609 cases from 45 eligible studies. Data were collected by consensus of the first two authors with the third author arbitrating disparities of opinion. Success was taken as the closure rate at 12 months where possible. Forest plots with Mantel-Haenszel analyses were used to compare closure rates with respect to perforation size, adenoidectomy, status of contralateral ear, Eustachian tube function, active infection, and graft position. Linear regression and Fisher's exact were used to analyze closure rate with respect to age. The mean weighted closure rate for pediatric tympanoplasty was 83.4%. Subgroup analysis found age not to be a significant factor affecting the closure rate. Tympanoplasties performed on larger perforations or in children with abnormal contralateral ear findings were more likely to fail. Surgery may be best delayed until contralateral otitis media with effusion has settled.
Egbor, Peter E; Saheeb, Birch D
2014-01-01
Objective: The aim of the following study is to determine the effect of primary closure or dressing on post-operative morbidity after impacted lower third molar surgery. Materials and Methods: This was a randomized clinical study of 72 patients who had surgical extraction of impacted mandibular third molars. The subjects were divided into two groups of A and B. Group A had total closure (primary closure) and Group B had whitehead varnish dressing of the socket. Pain, swelling and trismus were evaluated pre-operatively using visual analogue scale, flexible tape measuring method and inter-incisal distance measurement with Vernier Callipers respectively as well as post-operatively on 1st, 2nd, 3rd, 5th and 7th day. Results: The study participants consisted of 27 males and 45 females in a ratio 1:1.7. With a mean age of 24.7 ± 4.9 years (range 19-33 years) for Group A and 25.5 ± 4.3 years (range 20-39 years) for Group B. Post-operative pain was not significantly affected by the closure techniques (P > 0.05). Dressing was found to significantly reduce the degree of swelling and trismus peaking on the 2nd day (P = 0.0207 and P = 0.010 respectively). Conclusion: The use of dressing was more effective than primary closure to reduce the degree of swelling and trismus though its effect on post-operative pain reduction was not significant. PMID:25191094
Mansencal, Nicolas; Mitry, Emmanuel; Pillière, Rémy; Lepère, Céline; Gérardin, Benoît; Petit, Jérôme; Gandjbakhch, Iradj; Rougier, Philippe; Dubourg, Olivier
2008-04-01
The aim of this study was to assess (1) the incidence of patent foramen ovale (PFO) in carcinoid syndrome (CS) and (2) the feasibility of percutaneous closure procedure in selected patients with CS. One hundred eight patients were prospectively studied: 54 with CS and an age- and gender-matched control group. All patients underwent conventional and contrast echocardiography. Patients with clinical signs of dyspnea (New York Heart Association class > or =III), cyanosis, carcinoid heart disease (CHD), and severe PFO were referred for the percutaneous closure of PFO. The prevalence of PFO was 41% in patients with CS and 22% in the control group (p = 0.03) and was significantly higher in patients with CHD (59%, p = 0.009). Four patients (14% of those with CHD) were referred for the percutaneous closure of PFO, and 3 patients ultimately underwent PFO closure (using Amplatzer septal occluders). At 6-month follow-up, New York Heart Association class was improved in all patients, as well as arterial blood gas results (p = 0.04) and 6-minute walking distance (p = 0.03), but all patients presented residual right-to-left shunts. In conclusion, this prospective study demonstrates that in patients with CHD, the prevalence of PFO is high and that percutaneous closure of PFO is feasible, with a reduction in symptoms but with residual shunting.
Howell-Taylor, Melania; Hall, Macy G; Brownlee Iii, William J; Taylor, Mary
2008-09-01
Acute infection of surgical incision sites often requires specialized wound care in preparation for surgical closure. Optimal therapy for preparing such wounds for a secondary closure procedure remains uncertain. The authors report wound outcomes after administering acoustic pressure wound therapy in conjunction with negative pressure wound therapy with reticulated open-cell foam dressing changes to assist with bacteria removal from open, infected surgical-incision sites in preparation for secondary surgical closure in three patients. Before incorporating acoustic pressure wound therapy at the authors' facility, the average negative pressure wound therapy with reticulated open-cell foam dressing course prior to secondary surgical closure was 30 days; with its addition, two of three patients underwent successful surgical closure with no postoperative complications after 21 and 14 days, respectively; one patient succumbed to nonwound-related complications before wound closure. Larger, prospective studies are needed to evaluate combining negative pressure wound therapy with reticulated open-cell foam dressing and acoustic pressure wound therapy for infected, acute post surgery wounds.
Relationship between relative lens position and appositional closure in eyes with narrow angles.
Otori, Yasumasa; Tomita, Yuki; Hamamoto, Ayumi; Fukui, Kanae; Usui, Shinichi; Tatebayashi, Misako
2011-03-01
To investigate the relationship between relative lens position (RLP) and appositional closure in eyes with narrow angles. Ultrasound biomicroscopy (UBM) was used to measure anterior chamber depth (ACD) and lens thickness (LT), and the IOLMaster to measure axial length (AL). The number of quadrants with appositional closure was assessed by UBM under dark conditions. The RLP was calculated thus: RLP = 10 × (ACD + 0.5 LT) /AL. This study comprised 30 consecutive patients (30 eyes) with narrow-angle eyes defined as Shaffer grade 2 or lower and without peripheral anterior synechiae (24 women, 6 men; mean age ± SD, 67.3 ± 10.4 years; range, 42-87 years). Under dark conditions, 66.7% of the eyes with narrow angles showed appositional closure in at least one quadrant. Of the various ocular biometric parameters, only the RLP significantly decreased with appositional closure in at least one quadrant (P = 0.005). A decrease in the RLP can be predictive of appositional closure for narrow-angle eyes under dark conditions.
40 CFR 265.146 - Use of a mechanism for financial assurance of both closure and post-closure care.
Code of Federal Regulations, 2013 CFR
2013-07-01
... assurance of both closure and post-closure care. 265.146 Section 265.146 Protection of Environment... Use of a mechanism for financial assurance of both closure and post-closure care. An owner or operator may satisfy the requirements for financial assurance for both closure and post-closure care for one or...
Is size the only determinant of delayed abdominal closure in pediatric liver transplant?
Khorsandi, Shirin Elizabeth; Day, Arthur William Raven; Cortes, Miriam; Deep, Akash; Dhawan, Anil; Vilca-Melendez, Hector; Heaton, Nigel
2017-03-01
The aim was to determine the factors associated with the use of delayed abdominal closure in pediatric liver transplantation (LT) and whether this affected outcome. From a prospectively maintained database, transplants performed in children (≤18 years) were identified (October 2010 to March 2015). Primary abdominal closure was defined as mass closure performed at time of transplant. Delayed abdominal closure was defined as mass closure not initially performed at the same time as transplant; 230 children underwent LT. Of these, 176 (76.5%) had primary closure. Age was similar between the primary and delayed groups (5.0 ± 4.9 versus 3.9 ± 5.0 years; P = 0.13). There was no difference in the graft-to-recipient weight ratio (GRWR) in the primary and delayed groups (3.4 ± 2.8 versus 4.1 ± 2.1; P = 0.12). Children with acute liver failure (ALF) were more likely to experience delayed closure then those with chronic liver disease (CLD; P < 0.001). GRWR was similar between the ALF and CLD (3.4 ± 2.4 versus 3.6 ± 2.7; P = 0.68). Primary closure children had a shorter hospital stay (P < 0.001), spent fewer days in pediatric intensive care unit (PICU; P = 0.001), and required a shorter duration of ventilation (P < 0.001). Vascular complications (arterial and venous) were similar (primary 8.2% versus delayed 5.6%; P = 0.52). Graft (P = 0.42) and child survival (P = 0.65) in the primary and delayed groups were similar. Considering timing of mass closure after transplant, patients in the early delayed closure group (<6 weeks) were found to experience a shorter time of ventilation (P = 0.03) and in PICU (P = 0.003). In conclusion, ALF was the main determinant of delayed abdominal closure rather than GRWR. The optimal time for delayed closure is within 6 weeks. The use of delayed abdominal closure does not adversely affect graft/child survival. Liver Transplantation 23 352-360 2017 AASLD. © 2016 by the American Association for the Study of Liver Diseases.
Surgical complications associated with primary closure in patients with diabetic foot osteomyelitis
García-Morales, Esther; Lázaro-Martínez, José Luis; Aragón-Sánchez, Javier; Cecilia-Matilla, Almudena; García-Álvarez, Yolanda; Beneit-Montesinos, Juan Vicente
2012-01-01
Background The aim of this study was to determine the incidence of complications associated with primary closure in surgical procedures performed for diabetic foot osteomyelitis compared to those healed by secondary intention. In addition, further evaluation of the surgical digital debridement for osteomyelitis with primary closure as an alternative to patients with digital amputation was also examined in our study. Methods Comparative study that included 46 patients with diabetic foot ulcerations. Surgical debridement of the infected bone was performed on all patients. Depending on the surgical technique used, primary surgical closure was performed on 34 patients (73.9%, Group 1) while the rest of the 12 patients were allowed to heal by secondary intention (26.1%, Group 2). During surgical intervention, bone samples were collected for both microbiological and histopathological analyses. Post-surgical complications were recorded in both groups during the recovery period. Results The average healing time was 9.9±SD 8.4 weeks in Group 1 and 19.1±SD 16.9 weeks in Group 2 (p=0.008). The percentage of complications was 61.8% in Group 1 and 58.3% in Group 2 (p=0.834). In all patients with digital ulcerations that were necessary for an amputation, a primary surgical closure was performed with successful outcomes. Discussion Primary surgical closure was not associated with a greater number of complications. Patients who received primary surgical closure had faster healing rates and experienced a lower percentage of exudation (p=0.05), edema (p<0.001) and reinfection, factors that determine the delay in wound healing and affect the prognosis of the surgical outcome. Further research with a greater number of patients is required to better define the cases for which primary surgical closure may be indicated at different levels of the diabetic foot. PMID:23050062
Echocardiographic Follow-Up of Patent Foramen Ovale and the Factors Affecting Spontaneous Closure.
Yildirim, Ali; Aydin, Alperen; Demir, Tevfik; Aydin, Fatma; Ucar, Birsen; Kilic, Zubeyir
2016-11-01
The aim of the present study was to evaluate the echocardiographic follow-up of patent foramen ovale, which is considered a potential etiological factor in various diseases, and to determine the factors affecting spontaneous closure. Between January 2000 and June 2012, records of 918 patients with patent foramen ovale were retrospectively reviewed. Patency of less than 3 mm around the fossa ovalis is called patent foramen ovale. Patients with cyanotic congenital heart diseases, severe heart valve disorders and severe hemodynamic left to right shunts were excluded from the study. The patients were divided into three groups based on age; 1 day-1 month in group 1, 1 month-12 months in group 2, and more than 12 months in group 3. Of the 918 patients, 564 (61.4%) had spontaneous closure, 328 (35.8%) had patent foramen ovale continued, 15 (1.6%) patients had patent foramen ovale enlarged to 3-5 mm, 6 patients were enlarged to 5-8 mm, and in one patient patent foramen ovale reached to more than 8 mm size. Defect was spontaneously closed in 65.9% of the patients in group 1, 66.7% of the patients in group 2, and 52.3% of the patients in group 3. There was a negative correlation between the age of diagnosis and spontaneous closure (p < 0.05). Gender, prematurity and coexisting malformations such as patent ductus arteriosus and atrial septal aneurysm did not have any effect on spontaneous closure of patent foramen ovale (p > 0.05). However, ventricular septal defect and spontaneous closure of patent foramen ovale had a positive correlation (p < 0.01). No correlation was noted between the existence of atrial septal aneurysm, prematurity, and maturity of the patients. The present study demonstrated that spontaneous closure rate of patent foramen ovale is high. Furthermore, a positive correlation was found between spontaneous closure of patent foramen ovale with early diagnosis and small defect size.
Keller, Krista A; Paul-Murphy, Joanne; Weber, E P Scott; Kass, Philip H; Guzman, Sanchez-Migallon David; Park, Shin Ae; Raghunathan, Vijay Krishna; Gustavsen, Kate A; Murphy, Christopher J
2014-12-01
Wounds in reptiles are a common reason for presentation to a veterinarian. At this time there is limited information on effective topical medications to aid in wound closure. The objectives of this study were to translate the splinted, full-thickness dermal wound model, validated in mice, to the bearded dragon (Pogona vitticeps) and to determine the effect of topical becaplermin (BP), a platelet-derived growth factor (0.01%), on the rate of wound closure. Ten bearded dragons were anesthetized and two full-thickness cutaneous wounds were made on the dorsum of each lizard. Encircling splints were applied surrounding each wound and subsequently covered by a semi-occlusive dressing. Five lizards had one wound treated with BP and the adjacent wound treated with a vehicle control. Five additional lizards had one wound treated with saline and the second wound treated with a vehicle control. Wounds were imaged daily, and the wound area was measured using digital image analysis. The change in percentage wound closure over 17 days and the time to 50% wound closure was compared among the four treatment groups. There was no significant difference in wound closure rates between BP-treated and saline-treated wounds or in the time to 50% wound closure between any treatments. Vehicle-treated wounds adjacent to saline-treated wounds closed significantly slower than did BP (P < 0.010), saline (P < 0.001), and vehicle-treated wounds adjacent to BP-treated wounds (P < 0.013). Our preliminary study indicates that the splinted wound model, with modifications, may be used to determine wound closure rates in bearded dragons. When compared with saline, BP did not have a significant effect on wound closure rates, while the vehicle alone delayed wound closure. Histologic analysis of experimentally created wounds throughout the wound healing process is needed to further evaluate the effects of these treatments on reptile dermal wound healing.
Management Modalities for Traumatic Macular Hole: A Systematic Review and Single-Arm Meta-Analysis.
Gao, Min; Liu, Kun; Lin, Qiurong; Liu, Haiyun
2017-02-01
The purposes of this study were to (i) determine macular hole (MH) closure rates and visual outcomes by comparing two methods of managing traumatic MH (TMH)-an event resulting in severe loss of visual acuity (VA); (ii) characterize patients who undergo spontaneous TMH closure; (iii) determine which TMH patients should be observed before resorting to surgical repair; and (iv) elucidate factors that influence postoperative visual outcomes. Studies (n=10) of patients who were managed by surgery or observation for TMH were meta-analyzed retrospectively. Management modalities included surgical repair (surgery group) and observation for spontaneous hole closure (observation group). In addition, a 12-case series of articles (1990-2014) on spontaneous hole closure was statistically summarized. SAS and Comprehensive Meta-Analysis (CMA) (version 3.0) were used for analysis. For surgery group patients, the fixed-model pooled event rate for hole closure was 0.919 (range, 0.861-0.954) and for observation group patients, 0.368 (range, 0.236-0.448). The random-model pooled event rate for improvement of visual acuity (VA) for surgery group patients was 0.748 (range, 0.610-0.849) and for observation group patients, 0.505 (range, 0.397-0.613). For patients in both groups, the mean age of spontaneous closure was 18.71±10.64 years; mean size of TMHs, 0.18±0.06 decimal degrees (DD); and mean time for hole closure, 3.38±3.08 months. The pooled event rate for visual improvement was 0.748 (0.610-0.849). Hole closure and VA improvement rates of surgery group patients were significantly higher than those for observation group patients. Patients of ≤ 24 years of age with MH sizes of ≤ 0.2DD were more likely to achieve spontaneous hole closure. The interval of time from injury to surgery was statistically significantly associated with the level of visual improvement.
Wolfrum, Mathias; Froehlich, Georg M; Knapp, Guido; Casaubon, Leanne K; DiNicolantonio, James J; Lansky, Alexandra J; Meier, Pascal
2014-03-01
The role of percutaneous closure of patent foramen oval (PFO) in patients with cryptogenic stroke has been very controversial for years due to a lack of clear evidence. Systematic review and meta-analysis of the effect of percutaneous PFO closure for secondary prevention of cryptogenic strokes as compared to best medical therapy (BMT). Trials were identified through a literature search until 28 May 2013. Controlled clinical trials (randomised and non-randomised) comparing percutaneous PFO closure with BMT. Main end point of interest was stroke. A random effects model was used to calculate the pooled relative risks (RR) with 95% CIs. A total of 14 studies (three randomised controlled trials (RCT) and 11 non-randomised observational studies (non-RCT)), and a total of 4335 patients were included for this analysis. There was no significant treatment effect of PFO closure regarding stroke among the RCT (RR 0.66, 95% CI 0.37 to 1.19, p=0.171). However, among non-RCT stroke was reduced (RR 0.37, 95% CI 0.20 to 0.67, p<0.001) after PFO closure. A time-to-event (stroke) analysis, combining all three RCT and the two non-RCT which applied strict multivariate adjustments, showed a borderline significant risk reduction after PFO closure (HR 0.58, 95% CI 0.33 to 0.99, p=0.047). Neither risk of bleeding nor mortality differed significantly between the groups. However, there was a higher incidence of new onset atrial fibrillation in the closure group (RR 3.50, 95% CI 1.47 to 8.35, p=0.005). Percutaneous closure of PFO in patients with cryptogenic stroke does not appear superior to medical therapy according to currently available randomised data. Furthermore, it is associated with an increased incidence of atrial fibrillation. However, there are signals pointing towards a potential benefit and more research should be strongly encouraged.
Endoscopic full-thickness resection and defect closure in the colon.
von Renteln, Daniel; Schmidt, Arthur; Vassiliou, Melina C; Rudolph, Hans-Ulrich; Caca, Karel
2010-06-01
Endoscopic full-thickness resection (eFTR) is a minimally invasive method for en bloc resection of GI lesions. The aim of this pilot study was to evaluate the feasibility of a grasp-and-snare technique for eFTR combined with an over-the-scope clip (OTSC) for defect closure. Nonsurvival animal study. Animal laboratory. Fourteen female domestic pigs. The eFTR was performed in porcine colons using a novel tissue anchor in combination with a standard monofilament snare and 14 mm OTSC. In the first group (n = 20), closure of the colonic defects with OTSC was attempted after the resection. In the second group (n = 8), an endoloop was used to secure the resection base before eFTR was performed. In the first group (n = 20), eFTR specimens ranged from 2.4 to 5.5 cm in diameter. Successful closure was achieved in 9 out of 20 cases. Mean burst pressure for OTSC closure was 29.2 mm Hg (range, 2-90; SD, 29.92). Injury to adjacent organs occurred in 3 cases. Lumen obstruction due to the OTSC closure occurred in 3 cases. In the second group (n = 8), the diameter of specimens ranged from 1.2 to 2.2 cm. Complete closure was achieved in all cases, with a mean burst pressure of 76.6 mm Hg (range, 35-120; SD, 31). Lumen obstruction due to the endoloop closure occurred in one case. No other complications or injuries were observed in the second group. Nonsurvival setting. Colonic eFTR using the grasp-and-snare technique is feasible in an animal model. Ligation of the resection base with an endoloop before eFTR seems to reduce complication rates and improve closure success and leak test results despite yielding smaller specimens. Copyright 2010 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.
Boyd, Matt; Baker, Michael G; Mansoor, Osman D; Kvizhinadze, Giorgi; Wilson, Nick
2017-01-01
Countries are well advised to prepare for future pandemic risks (e.g., pandemic influenza, novel emerging agents or synthetic bioweapons). These preparations do not typically include planning for complete border closure. Even though border closure may not be instituted in time, and can fail, there might still plausible chances of success for well organized island nations. To estimate costs and benefits of complete border closure in response to new pandemic threats, at an initial proof-of-concept level. New Zealand was used as a case-study for an island country. An Excel spreadsheet model was developed to estimate costs and benefits. Case-study specific epidemiological data was sourced from past influenza pandemics. Country-specific healthcare cost data, valuation of life, and lost tourism revenue were imputed (with lost trade also in scenario analyses). For a new pandemic equivalent to the 1918 influenza pandemic (albeit with half the mortality rate, "Scenario A"), it was estimated that successful border closure for 26 weeks provided a net societal benefit (e.g., of NZ$11.0 billion, USD$7.3 billion). Even in the face of a complete end to trade, a net benefit was estimated for scenarios where the mortality rate was high (e.g., at 10 times the mortality impact of "Scenario A", or 2.75% of the country's population dying) giving a net benefit of NZ$54 billion (USD$36 billion). But for some other pandemic scenarios where trade ceased, border closure resulted in a net negative societal value (e.g., for "Scenario A" times three for 26 weeks of border closure-but not for only 12 weeks of closure when it would still be beneficial). This "proof-of-concept" work indicates that more detailed cost-benefit analysis of border closure in very severe pandemic situations for some island nations is probably warranted, as this course of action might sometimes be worthwhile from a societal perspective.
Pore formation and pore closure in poly(D,L-lactide-co-glycolide) films.
Fredenberg, Susanne; Wahlgren, Marie; Reslow, Mats; Axelsson, Anders
2011-03-10
Pore formation and pore closure in poly(D,L-lactide-co-glycolide)-based drug delivery systems are two important processes as they control the release of the encapsulated drug. The phenomenon pore closure was investigated by studying the effects of the pH and the temperature of the release medium, and the properties of the polymer. Poly(D,L-lactide-co-glycolide) (PLG) films were subjected to a pore forming pre-treatment, and then pore closure was observed simultaneously with changes in glass transition temperature, wettability (contact angle), water absorption and mass remaining. To further understand the effect of pH, combined pore formation and pore closure were studied at different pH values. Pore closure was increased in a release medium with low pH, with a low-molecular-weight PLG of relatively low degree of hydrophobicity, or at high temperature. Pore closure occurred by two different mechanisms, one based on polymer-polymer interactions and one on polymer-water interactions. The mobility of the PLG chains also played an important role. The surface of the PLG films were more porous at pH 5-6 than at lower or higher pH, as pore formation was relatively fast and pore closure were less pronounced in this pH range. The pH had a significant impact on the porous structure, which should be kept in mind when evaluating experimental results, as the pH may be significantly decreased in vitro, in vivo and in situ. The results also show that the initial porosity is very important when using a high-molecular-weight PLG. Copyright © 2010 Elsevier B.V. All rights reserved.
Association of iris crypts with acute primary angle closure.
Koh, Victor; Chua, Jacqueline; Shi, Yuan; Thakku, Sri Gowtham; Lee, Ryan; Nongpiur, Monisha E; Baskaran, Mani; Kumar, Rajesh S; Perera, Shamira; Aung, Tin; Cheng, Ching-Yu
2017-10-01
To determine the relationship between iris surface features and acute primary angle closure (APAC) in eyes with angle closure. Case-control study involving Asian patients diagnosed with previous APAC, primary angle closure suspect (PACS), primary angle closure (PAC) and primary angle closure glaucoma (PACG) at an eye centre in Singapore between August 2012 and January 2015. Participants underwent ophthalmic examination and digital slit-lamp iris photography. Iris surface features were graded based on crypts, furrows and colour. Fellow eyes of APAC were compared with PACS and PAC/PACG eyes with regard to their iris surface features. Occurrence of APAC. A total of 309 patients (71 APAC, 139 PACS, 47 PAC and 52 PACG) were included (mean age: 67.7±7.2 years and 36.6% male). Compared with PACS, higher crypt grade was significantly associated with lower odds of APAC (OR=0.58 for one grade higher in crypt grade; p=0.027, adjusted for age, gender, ethnicity and pupil diameter). The results remained similar when compared with PAC/PACG group (OR=0.58 for one grade higher in crypt grade; p=0.043). We did not observe any significant associations between iris furrows or colour with presence of APAC. Our study comprising Asian eyes with angle closure suggests that the presence of a higher crypt grading may be protective for APAC. As such, assessing iris surface architecture for crypts could be a new measure for risk stratification of developing APAC in eyes with angle closure. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Diana, M; Leroy, J; Wall, J; De Ruijter, V; Lindner, V; Dhumane, P; Mutter, D; Marescaux, J
2012-06-01
Endoluminal full-thickness closure of the rectal wall is critical in emerging procedures including endoscopic submucosal dissection and transrectal natural orifice transluminal endoscopic surgery (NOTES). This study aimed to compare manual suture using the transanal endoscopic operation platform (TEO; Karl Storz, Tüttlingen, Germany) with the end-to-end anastomosis hemorrhoid circular stapler (EEA; Covidien, Dublin, Ireland) for closure of the rectal viscerotomy during transrectal NOTES segmental colectomy. A total of 12 swine underwent transrectal hybrid NOTES partial colectomies. Animals were divided into two groups according to the viscerotomy closure technique: 1) TEO manual suture; 2) EEA circular stapler closure. Mean (± SD) viscerotomy closure time was 67.5 ± 59.5 minutes and 31.5 ± 19.6 minutes for TEO and EEA, respectively. There was one conversion to laparoscopy in the TEO group and a misfiring in the EEA group that required a TEO salvage suture. There was one positive air-leak test in each group. Peritoneal fluid collected at the end of the procedure tested positive for bacterial contamination in all cases. A mild stenosis was present in 4 /6 viscerotomies (67 %) in the TEO group and in 1/6 (17 %) in the EEA group on endoscopic control. Inflammatory changes were mild in 3/5 (60 %) and 4/5 (80 %) viscerotomies in the TEO and EEA groups, respectively, whereas severe inflammation was found in 2/5 (TEO) and 1 /5 (EEA). Transrectal viscerotomy closure using the EEA circular stapler technique is feasible, easy to perform, and histologically comparable to suture closure through a TEO platform. It may offer an attractive alternative for NOTES segmental colectomies and endoscopic resections. © Georg Thieme Verlag KG Stuttgart · New York.
Sanchis Calvo, A; Martínez- Frías, M
2001-02-01
To identify the frequency at birth of neural tube defects (NTD) in the Spanish population. NTDs were considered as a whole as well as according to the different sites of closure failure, following the theory of multisite closure of the neural tube. To analyze the epidemiological characteristics of the different sites. Data derived from the Spanish Collaborative Study of Congenital Malformations (ECEMC), from April 1976 to March 1995. Among the 1,222,698 live births during this period, 784 infants had NTD were controlled. Among these, 784 infants had NTD. The prevalence of NTD in our population was 1.01 per 1,000 births, a frequency which is considered medium-to low. Only 5.74% of the NTD were of known etiology: 2.17% were genic, 1.27% were chromosomic and 2.29% were environmental. Excluding NTD of genetic etiology, whether genic or chromosomic, most of the remaining were isolated defects (multifactorial) and 16.78% multiple malformations. Site 1, where the closure of the neural tube starts, represented 24% of all the affected sites. However, more than 50% of the NTDs corresponded to closure failure at the junction of two sites. As in other populations with a low prevalence of NTD at birth, the prevalence of these defects in our population showed a trend to decrease with time, due to the possibility of interrupting gestation after prenatal diagnosis. All the NTD could be classified according to the theory of multisite closure of the neural tube, including 13 cases with several noncontiguous affected sites. Two types of NTD were observed: in the first, closure failed to occur and in the second, two closures failed to meet.
Spalla, I; Locatelli, C; Zanaboni, A M; Brambilla, P; Bussadori, C
2016-05-01
Patent ductus arteriosus (PDA) is 1 of the most common congenital heart defects in dogs and percutaneous closure is effective in achieving ductal closure; PDA closure is associated with abrupt hemodynamic changes. A marked decrease in standard parameters of systolic function as assessed by M- or B-mode echocardiography after PDA closure was identified in previous studies. Speckle tracking echocardiography can provide further insight into the effect of PDA closure on cardiac mechanics in dogs affected by PDA. Twenty-five client-owned dogs with PDA. Prospective study. Dogs were recruited over a 2-year period. Complete echocardiographic evaluation was performed before and 24 hours after PDA closure, including standard (end-diastolic volumes indexed to body surface area in B- and M-mode [EDVIB /M ], end-systolic volumes indexed to body surface area in B- and M-mode [ESVIB /M ], allometric scaling in diastole [AlloD] and systole [AlloS], pulmonary flow to systemic flow [Qs/Qp], ejection fraction [EF], and fractional shortening [FS]), and advanced speckle-tracking echocardiography (STE): global longitudinal, radial, circumferential and transverse strain (S), and strain rate (SR). Patent ductus arteriosus closure was associated with statistically significant decreases in EDVIM /B and ESVIM /B , AlloD and AlloS, SI, EF, and FS. A statistically significant decrease in the absolute values of radial, transverse, and circumferential S and SR was observed, whereas longitudinal S and SR did not change significantly. Patent ductus arteriosus closure by percutaneous approach is associated with marked decreases of conventional echocardiographic parameters as a result of the changes in loading conditions, but no evidence of systolic dysfunction was identified by means of STE, as none of the S and SR values were below reference ranges. In the short term, contractility is enhanced in the long axis (long S/SR values were not statistically different before and after closure) and decreases to normal values in short axis (circumferential, radial, and transversal S/SR decreased to normal reference range). Copyright © 2016 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.
Suitable closure for post-duodenal endoscopic resection taking medical costs into consideration
Mori, Hirohito; Ayaki, Maki; Kobara, Hideki; Fujihara, Shintaro; Nishiyama, Noriko; Matsunaga, Tae; Yachida, Tatsuo; Masaki, Tsutomu
2015-01-01
AIM: To compare closure methods, closure times and medical costs between two groups of patients who had post-endoscopic resection (ER) artificial ulcer floor closures. METHODS: Nineteen patients with duodenal adenoma, early duodenal cancer, and subepithelial tumors that received ER between September 2009 and September 2014 at Kagawa University Hospital and Ehime Rosai Hospital, an affiliated hospital of Kagawa University, were included in the study. We retrospectively compared two groups of patients who received post-ER artificial ulcer floor closure: the conventional clip group vs the over-the-scope clip (OTSC) group. Delayed bleeding, procedure time of closure, delayed perforation, total number of conventional clips and OTSCs and medical costs were analyzed. RESULTS: Although we observed delayed bleeding in three patients in the conventional clip group, we observed no delayed bleeding in the OTSC group (P = 0.049). We did not observe perforation in either group. The mean procedure times for ulcer closure were 33.26 ± 12.57 min and 9.71 ± 2.92 min, respectively (P = 0.0001). The resection diameters were 18.8 ± 1.30 mm and 22.9 ± 1.21 mm for the conventional clip group and the OTSC group, respectively, with significant difference (P = 0.039). As for medical costs, the costs of all conventional clips were USD $1257 and the costs of OTSCs were $7850 (P = 0.005). If the post-ER ulcer is under 20 mm in diameter, a conventional clip closure may be more suitable with regard to the prevention of delayed perforation and to medical costs. CONCLUSION: If the post-ER ulcer is over 20 mm, the OTSC closure should be selected with regard to safety and reliable closure even if there are high medical costs. PMID:25954101
Suitable closure for post-duodenal endoscopic resection taking medical costs into consideration.
Mori, Hirohito; Ayaki, Maki; Kobara, Hideki; Fujihara, Shintaro; Nishiyama, Noriko; Matsunaga, Tae; Yachida, Tatsuo; Masaki, Tsutomu
2015-05-07
To compare closure methods, closure times and medical costs between two groups of patients who had post-endoscopic resection (ER) artificial ulcer floor closures. Nineteen patients with duodenal adenoma, early duodenal cancer, and subepithelial tumors that received ER between September 2009 and September 2014 at Kagawa University Hospital and Ehime Rosai Hospital, an affiliated hospital of Kagawa University, were included in the study. We retrospectively compared two groups of patients who received post-ER artificial ulcer floor closure: the conventional clip group vs the over-the-scope clip (OTSC) group. Delayed bleeding, procedure time of closure, delayed perforation, total number of conventional clips and OTSCs and medical costs were analyzed. Although we observed delayed bleeding in three patients in the conventional clip group, we observed no delayed bleeding in the OTSC group (P = 0.049). We did not observe perforation in either group. The mean procedure times for ulcer closure were 33.26 ± 12.57 min and 9.71 ± 2.92 min, respectively (P = 0.0001). The resection diameters were 18.8 ± 1.30 mm and 22.9 ± 1.21 mm for the conventional clip group and the OTSC group, respectively, with significant difference (P = 0.039). As for medical costs, the costs of all conventional clips were USD $1257 and the costs of OTSCs were $7850 (P = 0.005). If the post-ER ulcer is under 20 mm in diameter, a conventional clip closure may be more suitable with regard to the prevention of delayed perforation and to medical costs. If the post-ER ulcer is over 20 mm, the OTSC closure should be selected with regard to safety and reliable closure even if there are high medical costs.
Ren, Jianan; Yuan, Yujie; Zhao, Yunzhao; Gu, Guosheng; Wang, Gefei; Chen, Jun; Fan, Chaogang; Wang, Xinbo; Li, Jieshou
2014-04-01
The use of open abdomen in the management of gastrointestinal fistula complicated with severe intra-abdominal infection is uncommon. This study was designed to evaluate outcomes of our staged approach for the infected open abdomen. Patients who had gastrointestinal fistula and underwent open abdomen treatment were retrospectively reviewed. Various materials such as polypropylene mesh and a modified sandwich package were used to achieve temporary abdominal closure followed by skin grafting when the granulation bed matured. A delayed definitive operation was performed for final abdominal closure without implant of prosthetic mesh. Between 1999 and 2009, 56 (68.3%) of 82 patients survived through this treatment. Among them, 42 patients achieved final abdominal closure. Spontaneous fistula closure occurred in 16 patients with secondary fistula recorded in six patients. Besides, wound complications occurred in 13 patients with two cases for pulmonary infection. Within a 12-month follow-up period after definitive closure, no additional fistula was recorded excluding planned ventral hernia repair. Open abdomen treatment was effective for gastrointestinal fistula complicated by severe intra-abdominal infection. A delayed and deliberate operative strategy aiming at fistula excision and fascial closure, with simultaneous abdominal wall reconstruction, was required for the infected open abdomen.
Composite three-layer closure of oral antral communication with 10 months follow-up-a case study.
Weinstock, Robert J; Nikoyan, Levon; Dym, Harry
2014-02-01
We propose a 3-layer composite closure technique for an oral antral communication (OAC) while avoiding secondary donor site morbidity. A patient had developed a 1-cm OAC after extraction of right maxillary first molar. The patient subsequently developed acute maxillary sinusitis. The patient was taken to the operating room, and a Caldwell-Luc procedure was performed. The bony window from the Caldwell-Luc was "press fit" over the bony OAC defect. Soft tissue closure was then achieved with a buccal fat pad flap and a buccal mucosal advancement flap. The patient was examined on postoperative day 5 and 1, 2, 3, 6, and 10 months postoperatively. The acute sinusitis had resolved. The soft tissue closure was successful. The bone graft remained intact, prevented sinus pneumatization, and restored continuity to the floor of the maxillary sinus. The presented technique for 3-layer closure of OACs allows for the stability of a double-layer closure of OAC with the added benefit of bone grafting from single operative site, achieving stable oral antral closure, bone grafting, and the avoidance of secondary donor site morbidity. Copyright © 2014 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.
Unstrained and strained flamelets for LES of premixed combustion
NASA Astrophysics Data System (ADS)
Langella, Ivan; Swaminathan, Nedunchezhian
2016-05-01
The unstrained and strained flamelet closures for filtered reaction rate in large eddy simulation (LES) of premixed flames are studied. The required sub-grid scale (SGS) PDF in these closures is presumed using the Beta function. The relative performances of these closures are assessed by comparing numerical results from large eddy simulations of piloted Bunsen flames of stoichiometric methane-air mixture with experimental measurements. The strained flamelets closure is observed to underestimate the burn rate and thus the reactive scalars mass fractions are under-predicted with an over-prediction of fuel mass fraction compared with the unstrained flamelet closure. The physical reasons for this relative behaviour are discussed. The results of unstrained flamelet closure compare well with experimental data. The SGS variance of the progress variable required for the presumed PDF is obtained by solving its transport equation. An order of magnitude analysis of this equation suggests that the commonly used algebraic model obtained by balancing source and sink in this transport equation does not hold. This algebraic model is shown to underestimate the SGS variance substantially and the implications of this variance model for the filtered reaction rate closures are highlighted.
Stress-induced, time-dependent fracture closure at hydrothermal conditions
Beeler, N.M.; Hickman, S.H.
2004-01-01
Time-dependent closure of fractures in quartz was measured in situ at 22-530??C temperature and 0.1-150 MPa water pressure. Unlike previous crack healing and rock permeability studies, in this study, fracture aperture is monitored directly and continuously using a windowed pressure vessel, a long-working-distance microscope, and reflected-light interferometry. Thus the fracture volume and geometry can be measured as a function of time, temperature, and water pressure. Relatively uniform closure occurs rapidly at temperatures and pressures where quartz becomes significantly soluble in water. During closure the aperture is reduced by as much as 80% in a few hours. We infer that this closure results from the dissolution of small particles or asperities that prop the fracture open. The driving force for closure via dissolution of the prop is the sum of three chemical potential terms: (1) the dissolution potential, proportional to the logarithm of the degree of undersaturation of the solution; (2) the coarsening potential, proportional to the radius of curvature of the prop; and (3) the pressure solution potential, proportional to the effective normal stress at the contact between propping particles and the fracture wall. Our observations suggest that closure is controlled by a pressure solution-like process. The aperture of dilatant fractures and microcracks in the Earth that are similar to those in our experiments, such as ones generated from thermal stressing or brittle failure during earthquake rupture and slip, will decrease rapidly with time, especially if the macroscopic stress is nonhydrostatic.
Ishida, Hidekazu; Kawazu, Yukiko; Kayatani, Futoshi; Inamura, Noboru
2017-05-01
A number of case reports show various outcomes of premature closure of the ductus arteriosus in utero, including persistent pulmonary hypertension of the newborn and fetal or neonatal death; however, no study clarifies the clinical observations that are related to their prognoses. We aimed to clarify the prognostic factors of intrauterine ductal closure by a systematic literature review. Data sources We searched PubMed database (1975-2014) to identify case reports and studies on intrauterine closure of the ductus arteriosus, including maternal, fetal, and neonatal clinical information and their prognoses. We analysed the data of 116 patients from 39 articles. Of these, 12 (10.3%) died after birth or in utero. Fetal or neonatal death was significantly correlated with fetal hydrops (odds ratio=39.6, 95% confidence interval=4.6-47.8) and complete closure of the ductus arteriosus (odds ratio=5.5, 95% confidence interval=1.2-15.1). Persistent pulmonary hypertension was observed in 33 cases (28.4%), and was also correlated with fetal hydrops (odds ratio=4.2, 95% confidence interval=1.3-4.6) and complete closure of the ductus arteriosus (odds ratio=5.5, 95% confidence interval=1.6-6.0). Interestingly, maternal drug administration was not correlated with the risk of death and persistent pulmonary hypertension. Fetal hydrops and complete ductal closure are significant risk factors for both death and persistent pulmonary hypertension. Cardiac or neurological prognoses could be favourable if the patients overcome right heart failure during the perinatal period.
Stress-induced, time-dependent fracture closure at hydrothermal conditions
NASA Astrophysics Data System (ADS)
Beeler, N. M.; Hickman, S. H.
2004-02-01
Time-dependent closure of fractures in quartz was measured in situ at 22-530°C temperature and 0.1-150 MPa water pressure. Unlike previous crack healing and rock permeability studies, in this study, fracture aperture is monitored directly and continuously using a windowed pressure vessel, a long-working-distance microscope, and reflected-light interferometry. Thus the fracture volume and geometry can be measured as a function of time, temperature, and water pressure. Relatively uniform closure occurs rapidly at temperatures and pressures where quartz becomes significantly soluble in water. During closure the aperture is reduced by as much as 80% in a few hours. We infer that this closure results from the dissolution of small particles or asperities that prop the fracture open. The driving force for closure via dissolution of the prop is the sum of three chemical potential terms: (1) the dissolution potential, proportional to the logarithm of the degree of undersaturation of the solution; (2) the coarsening potential, proportional to the radius of curvature of the prop; and (3) the pressure solution potential, proportional to the effective normal stress at the contact between propping particles and the fracture wall. Our observations suggest that closure is controlled by a pressure solution-like process. The aperture of dilatant fractures and microcracks in the Earth that are similar to those in our experiments, such as ones generated from thermal stressing or brittle failure during earthquake rupture and slip, will decrease rapidly with time, especially if the macroscopic stress is nonhydrostatic.
Hsia, Renee Y.; Srebotnjak, Tanja; Kanzaria, Hemal K.; McCulloch, Charles; Auerbach, Andrew D.
2015-01-01
Study Objective Emergency Department (ED) closures threaten community access to emergency services, but few data exist to describe factors associated with closure. We evaluated factors associated with ED closure in California and sought to determine if hospitals serving more vulnerable populations have a higher rate of ED closure. Methods Retrospective cohort study of California hospital EDs between 1998 and 2008, using hospital and patient level data from the California Office of Statewide Planning and Development (OSHPD), as well as OSHPD Patient Discharge Data. We examined the effects of hospital and patient factors on the hospital's likelihood of ED closure using Cox proportional hazards models. Results In 4,411 hospital-years of observation, 29 of 401 (7.2%) EDs closed. In a model adjusted for total ED visits, hospital discharges, trauma center and teaching status, ownership, operating margin, and urbanicity, hospitals with more black patients (OR 1.41 per increase in proportion of blacks by 0.1, 95% CI 1.16-1.72) and Medi-Cal recipients (OR 1.17 per increase in proportion insured by Medi-Cal by 0.1, 95% CI 1.02-1.34) had higher odds for ED closure, as did for-profit institutions (OR 1.65, 95% CI 1.13-2.41). Conclusion The population served by EDs and hospitals’ profit model are associated with ED closure. Whether our findings are a manifestation of poorer reimbursement in at-risk EDs is unclear. PMID:22093435
Romanelli, John R; Desilets, David J; Chapman, Christopher N; Surti, Vihar C; Lovewell, Carolanne; Earle, David B
2010-12-01
Transgastric NOTES(®) procedures remain without a simple method to close the gastrotomy. In four survival swine studies, we have tested a novel gastric closure device: the loop-anchor purse-string (LAPS) closure system. In four anesthetized pigs, an endoscopic gastrotomy was performed. Four loop anchors were arrayed in a 2-cm square pattern around the gastrotomy. The endoscope was passed into the abdominal cavity, and the gastrotomy was cinched closed. Procedure times ranged from 50-180 minutes. Three pigs survived 14 days. One animal was sacrificed early due to signs of sepsis. Another animal developed fevers and was treated with antibiotics. At necropsy, there were no abscesses, including in the septic animal. Histologic examination revealed evidence of healing in all animals. The LAPS system holds promise with early success in an animal model. Future human studies are needed to determine viability as a human visceral closure device.
Hardwood Face Veneer and Plywood Mill Closures in Michigan and Wisconsin Since 1950
Lewis T. Hendricks
1966-01-01
In recent years there has been a great deal of concern about the closure of numberous hardwood face veneer and plywood mills in Michigan and Wisconsin. As part of an overall study of that industry in the northern Lake States region, the basic reasons leading to the closure of these mills were investigated. In the past 15 years, there have been eight known mill...
Mansouri, Mohammadreza; Ramezani, Farshid; Moghimi, Sasan; Tabatabaie, Ali; Abdi, Fatemeh; He, Mingguang; Lin, Shan C
2014-10-21
To describe anterior segment optical coherence tomography (AS-OCT) parameters in phacomorphic angle closure eyes, mature cataract eyes, and their fellow eyes, and identify those parameters that could be used to differentiate phacomorphic angle closure eyes from those with mature cataract and no phacomorphic angle closure. In this cross-sectional study, a total of 33 phacomorphic angle closure subjects and 34 control patients with unilateral mature cataracts were enrolled. All patients underwent AS-OCT imaging and A-scan biometry of both eyes. Anterior chamber depth (ACD), anterior chamber area (ACA), iris thickness, iris curvature, lens vault (LV), and angle parameters, including angle opening distance (AOD750) and trabecular-iris space area (TISA750), were measured in qualified images using customized software and compared among eyes with phacomorphic angle closure, mature cataract eyes, and their fellow eyes. There was no significant difference in axial length among the four groups. Phacomorphic angle closure had the smallest angle (AOD750, TISA750) and anterior chamber parameters (ACD, ACA, anterior chamber width) and the greatest LV among the groups. This pattern was similar when comparing fellow eyes of mature cataract patients and fellow eyes of phacomorphic angle closure. Anterior chamber area less than 18.62 mm(2), ACD less than 2.60 mm, LV greater than 532.0 μm, and AOD750 less than 0.218 mm had the highest odds ratios (ORs) for distinguishing fellow eyes of phacomorphic angle closure versus fellow eyes of mature cataracts, with OR values of 9.90, 8.31, 7.91, and 7.91, respectively. Logistic regression showed that ACA less than 18.62 was the major parameter associated with fellow eyes of phacomorphic angle closure (OR = 10.96, P < 0.001). Anterior chamber depth, ACA, AOD750, and LV are powerful indicators in differentiating phacomorphic angle closure eyes from those with mature cataract and their fellow eyes. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.
Tropical Intraseasonal Variability in Version 3 of the GFDL Atmosphere Model
NASA Astrophysics Data System (ADS)
Benedict, J. J.; Maloney, E. D.; Sobel, A. H.; Frierson, D. M.; Donner, L.
2012-12-01
Tropical intraseasonal variability is examined in version 3 of the Geophysical Fluid Dynamics Laboratory Atmosphere Model (AM3). Compared to its predecessor AM2, AM3 uses a new treatment of deep and shallow cumulus convection and mesoscale clouds. The AM3 cumulus parameterization is a mass flux-based scheme but also, unlike that in AM2, incorporates subgrid-scale vertical velocities; these play a key role in cumulus microphysical processes. The AM3 convection scheme allows multi-phase water substance produced in deep cumuli to be transported directly into mesoscale clouds, which strongly influence large-scale moisture and radiation fields. We examine four AM3 simulations, using a control model and three versions with different modifications to the deep convection scheme. In the control AM3, using a convective closure based on CAPE relaxation, both the MJO and Kelvin waves are weak compared to those in observations. By modifying the convective closure and trigger assumptions to inhibit deep cumuli, AM3 produces reasonable intraseasonal variability but a degraded mean state. MJO-like disturbances in the modified AM3 propagate eastward at roughly the observed speed in the Indian Ocean but up to twice the observed speed in the West Pacific. Distinct differences in intraseasonal convective organization and propagation exist among the modified AM3 versions. Differences in vertical diabatic heating profiles associated with the MJO are also found. The two AM3 versions with the strongest intraseasonal signals have a more prominent "bottom-heavy" heating profile leading the disturbance center and "top-heavy" heating profile following the disturbance. The more realistic heating structures are associated with an improved depiction of moisture convergence and intraseasonal convective organization in AM3.ag correlations of 850 hPa zonal wind with precipitation at (left column) 90°E and (right column) 150°E. Both fields are bandpass filtered (20-100 days) and averaged between 15°S-15°N. Solid (dashed) contours represent positive (negative) correlations that are shaded dark (light) gray if they exceed the 95% statistical significance level. We use ERAI and TRMM for the observed wind and rainfall fields. In the left panels, index reference longitudes and the 5 m/s phase speed are marked by vertical and slanted thick lines, respectively. Right panels also contain the 10 m/s phase speed line.
Local and nonlocal parallel heat transport in general magnetic fields
DOE Office of Scientific and Technical Information (OSTI.GOV)
Del-Castillo-Negrete, Diego B; Chacon, Luis
2011-01-01
A novel approach for the study of parallel transport in magnetized plasmas is presented. The method avoids numerical pollution issues of grid-based formulations and applies to integrable and chaotic magnetic fields with local or nonlocal parallel closures. In weakly chaotic fields, the method gives the fractal structure of the devil's staircase radial temperature profile. In fully chaotic fields, the temperature exhibits self-similar spatiotemporal evolution with a stretched-exponential scaling function for local closures and an algebraically decaying one for nonlocal closures. It is shown that, for both closures, the effective radial heat transport is incompatible with the quasilinear diffusion model.
Simple Skin-Stretching Device in Assisted Tension-Free Wound Closure.
Cheng, Li-Fu; Lee, Jiunn-Tat; Hsu, Honda; Wu, Meng-Si
2017-03-01
Numerous conventional wound reconstruction methods, such as wound undermining with direct suture, skin graft, and flap surgery, can be used to treat large wounds. The adequate undermining of the skin flaps of a wound is a commonly used technique for achieving the closure of large tension wounds; however, the use of tension to approximate and suture the skin flaps can cause ischemic marginal necrosis. The purpose of this study is to use elastic rubber bands to relieve the tension of direct wound closure for simultaneously minimizing the risks of wound dehiscence and wound edge ischemia that lead to necrosis. This retrospective study was conducted to evaluate our clinical experiences with 22 large wounds, which involved performing primary closures under a considerable amount of tension by using elastic rubber bands in a skin-stretching technique after a wide undermining procedure. Assessment of the results entailed complete wound healing and related complications. All 22 wounds in our study showed fair to good results except for one. The mean success rate was approximately 95.45%. The simple skin-stretching design enabled tension-free skin closure, which pulled the bilateral undermining skin flaps as bilateral fasciocutaneous advancement flaps. The skin-stretching technique was generally successful.
Abdelkarim, Ayman; Levi, Daniel S; Tran, Bao; Ghobrial, Joanna; Aboulhosn, Jamil
2016-12-01
This study aims to evaluate the safety and efficacy of transcatheter fenestrated ASD closure and to summarize the literature regarding the published techniques and outcomes of transcatheter partial ASD closure. Patients with left ventricular diastolic dysfunction (LVDD) or right ventricular (RV) dysfunction and/or pulmonary hypertension (PHT) may suffer untoward consequences of complete closure of an ostium secundum atrial septal defect (ASD). Therefore, for patients that fall under these categories we suggest partial occlusion of the defect, which may be better tolerated than complete defect closure. After obtaining IRB approval, a search for patients that have undergone percutaneous ASD closure was performed in the Ahmanson/UCLA Adult Congenital Heart Disease Center database to identify which patients received a fenestrated ASD closure device. Eight consecutive patients ranging between 22 and 83 years of age (mean 48 years) with PHT and/or LVDD or RV dysfunction who underwent fenestrated transcatheter ASD closure at UCLA were identified. None of the subjects experienced complications related to the procedure. Postprocedure clinical evaluation showed improvement in symptoms and exercise capacity. Available follow-up transthoracic echocardiography data (mean 4 months, range 0-20 months) demonstrated patent fenestrations in four of eight patients. None of the patients had thromboembolic or infectious complications and there were no device migrations, erosions or embolizations. Partial ASD occlusion in patients with diastolic dysfunction or RV dysfunction and/or PHT is safe and may be better tolerated than complete ASD closure in selected patients. © 2016 Wiley Periodicals, Inc.
Effective school actions for mitigating seasonal influenza outbreaks in Niigata, Japan.
Sugisaki, Koshu; Seki, Nao; Tanabe, Naohito; Saito, Reiko; Sasaki, Asami; Sasaki, Satoshi; Suzuki, Hiroshi
2013-01-01
Japan has implemented various school actions during seasonal influenza outbreaks since the 1950's under the School Health Law. However, the effective duration, extent, and timing of closures remain unresolved. We conducted a retrospective study on the relationship between elementary class closures and influenza outbreak control during four consecutive influenza seasons from the 2004-2005 to 2007-2008 school years in Joetsu, Niigata, Japan. Among a total of 1,061 classes of 72 schools, 624 cases of influenza outbreaks were documented among 61 schools. Class closures were carried out in a total of 62 cases in response to influenza outbreak, which was defined as a student absentee rate of greater than 10% due to influenza or influenza-like illness. Of these cases, two-day class closures were conducted the day after reaching a 10% student absentee rate in 28 cases and other types of closures were initiated in 34 cases. A markedly higher number of outbreak cases ended within one week for two-day class closures compared to the other types of closures (82.1% vs. 20.6%, respectively). The significant association between two-day class closures and interruption of an outbreak within one week was confirmed using a multivariable model adjusted for the season, grade, day of the week of an outbreak start, and absentee rate on the day of an outbreak start (OR, 3.18; 95% CI, 1.12-9.07; p = 0.030). Our results suggest that a two-day class closure carried out the day after reaching a 10% absentee rate is an effective approach for mitigating influenza outbreaks in elementary schools.
Khan, Khizar Ishtiaque; Mahmood, Shahid; Akmal, Muhammad; Waqas, Ahmed
2012-06-01
To compare the difference in the rate of surgical wound infection, patient's convenience and length of hospital stay between Primary Closure and Delayed Primary Closure in cases of complicated appendicitis in adults. This randomised control trial was conducted at the Combined Military Hospital, Kharian and Malir from June 5, 2006, to September 10, 2009. Patients > or = 15 years of both gender who underwent appendectomy through grid iron or Lanz incision and having complicated appendicitis were included. The 100 patients who were included in the study out of the initial size of 393, were randomised into two equal groups of 50 each (Group A: Primary Closure; Group B: Delayed Primary Closure) using a computer-generated table. All the surgeries were done by the same surgeon and the operative steps and antibiotic coverage were standardised. The rate of surgical wound infection, patient's convenience (on visual analogue scale in mm) and the length of hospital stay were recorded. Data was analysed using SPSS version 11, and p value was calculated. Demographic data, comorbids and medication of both the groups was comparable. There was no significant difference in rate of surgical wound infection (p > 0.05). The difference in patient's convenience and length of hospital stay were significant (p < 0.05), showing superiority of Primary Closure over Delayed Primary Closure with no added morbidity/mortality. Primary Closure in complicated appendicitis not only reduces the cost of treatment, but is also more convenient and satisfying for the patients, with no added risk of surgical wound infection.
Hu, Cindy X; Mantravadi, Anand; Zangalli, Camila; Ali, Mohsin; Faria, Bruno M; Richman, Jesse; Wizov, Sheryl S; Razeghinejad, M Reza; Moster, Marlene R; Katz, L Jay
2016-02-01
The aim of this study was to compare gonioscopy with Visante and Cirrus optical coherence tomography (OCT) for identifying angle structures and the presence of angle closure in patients with glaucoma. A secondary objective was to assess interrater agreement for gonioscopy grading among 3 independent examiners. Gonioscopy grading using Spaeth Classification and determination of angle-closure risk was performed on 1 randomly selected eye for 50 phakic patients. Images of the same eye using both Visante and Cirrus OCT were obtained in both light and dark conditions. Agreement of angle closure among 3 devices and interrater agreement for gonioscopy were determined using Cohen's κ (K) or Kendall's coefficient of concordance (W). Of the 50 patients, 60% were female, 64% were white, and the mean age was 62 years. Angle closure was detected in 18%, 16%, and 48% of quadrants with Visante, Cirrus, and gonioscopy, respectively. The scleral spur was identified in 56% and 50% of quadrants with Visante and Cirrus OCT, respectively. Visante and Cirrus OCT showed moderate agreement in detecting angle closure (K=0.42 light, K=0.53 dark) but slight-to-fair agreement with gonioscopy (Visante K=0.25, Cirrus K=0.15). Gonioscopy demonstrated substantial agreement in angle closure (K=0.65 to 0.68) and angle-closure risk assessment (W=0.83) among 3 examiners. Visante and Cirrus OCT imaging may have limited ability to identify angle closure because of difficulty identifying angle structures. Gonioscopy by well-trained clinicians had remarkably consistent agreement for identifying angle-closure risk.
Sá, Michel Pompeu Barros Oliveira; de Oliveira Neto, Luiz de Albuquerque Pereira; do Nascimento, Gabriella Caroline Sales; Vieira, Erik Everton da Silva; Martins, Gabriel Lopes; Rodrigues, Karine Coelho; Nascimento, Giulia Cioffi; de Menezes, Alexandre Motta; Lins, Ricardo Felipe de Albuquerque; Silva, Frederico Pires Vasconcelos; Lima, Ricardo Carvalho
2018-01-01
Objective We aimed to determine whether patent foramen ovale closure reduces the risk of stroke, also assessing some safety outcomes. Introduction The clinical benefit of closing a patent foramen ovale after a cryptogenic stroke has been an open question for several decades, so that it is necessary to review the current state of published medical data in this regard. Methods MEDLINE, EMBASE, CENTRAL/CCTR, SciELO, LI-LACS, Google Scholar and reference lists of relevant articles were searched for randomized controlled trials that reported any of the following outcomes: stroke, death, major bleeding or atrial fibrillation. Five studies fulfilled our eligibility criteria and included 3440 patients (1829 for patent foramen ovale closure and 1611 for medical therapy). Results The risk ratio (RR) for stroke in the "device closure" group compared with the "medical therapy" showed a statistically significant difference between the groups, favouring the "device closure" group (RR 0.400; 95% CI 0.183-0.873, P=0.021). There was no statistically significant difference between the groups regarding the safety outcomes death and major bleeding, but we observed an increase in the risk of atrial fibrillation in the "device closure group (RR 4.000; 95% CI 2.262-7.092, P<0.001). We also observed that the larger the proportion of effective closure, the lower the risk of stroke. Conclusion This meta-analysis found that stroke rates are lower with percutaneously implanted device closure than with medical therapy alone, being these rates modulated by the rates of effective closure. PMID:29617507
Occupancy estimation and the closure assumption
Rota, Christopher T.; Fletcher, Robert J.; Dorazio, Robert M.; Betts, Matthew G.
2009-01-01
1. Recent advances in occupancy estimation that adjust for imperfect detection have provided substantial improvements over traditional approaches and are receiving considerable use in applied ecology. To estimate and adjust for detectability, occupancy modelling requires multiple surveys at a site and requires the assumption of 'closure' between surveys, i.e. no changes in occupancy between surveys. Violations of this assumption could bias parameter estimates; however, little work has assessed model sensitivity to violations of this assumption or how commonly such violations occur in nature. 2. We apply a modelling procedure that can test for closure to two avian point-count data sets in Montana and New Hampshire, USA, that exemplify time-scales at which closure is often assumed. These data sets illustrate different sampling designs that allow testing for closure but are currently rarely employed in field investigations. Using a simulation study, we then evaluate the sensitivity of parameter estimates to changes in site occupancy and evaluate a power analysis developed for sampling designs that is aimed at limiting the likelihood of closure. 3. Application of our approach to point-count data indicates that habitats may frequently be open to changes in site occupancy at time-scales typical of many occupancy investigations, with 71% and 100% of species investigated in Montana and New Hampshire respectively, showing violation of closure across time periods of 3 weeks and 8 days respectively. 4. Simulations suggest that models assuming closure are sensitive to changes in occupancy. Power analyses further suggest that the modelling procedure we apply can effectively test for closure. 5. Synthesis and applications. Our demonstration that sites may be open to changes in site occupancy over time-scales typical of many occupancy investigations, combined with the sensitivity of models to violations of the closure assumption, highlights the importance of properly addressing the closure assumption in both sampling designs and analysis. Furthermore, inappropriately applying closed models could have negative consequences when monitoring rare or declining species for conservation and management decisions, because violations of closure typically lead to overestimates of the probability of occurrence.
Jeong, Jin-Seok; Lee, Seung-Youp; Chang, Moontaek
2016-06-01
The aim of this study was to evaluate alterations of papilla dimensions after orthodontic closure of the diastema between maxillary central incisors. Sixty patients who had a visible diastema between maxillary central incisors that had been closed by orthodontic approximation were selected for this study. Various papilla dimensions were assessed on clinical photographs and study models before the orthodontic treatment and at the follow-up examination after closure of the diastema. Influences of the variables assessed before orthodontic treatment on the alterations of papilla height (PH) and papilla base thickness (PBT) were evaluated by univariate regression analysis. To analyze potential influences of the 3-dimensional papilla dimensions before orthodontic treatment on the alterations of PH and PBT, a multiple regression model was formulated including the 3-dimensional papilla dimensions as predictor variables. On average, PH decreased by 0.80 mm and PBT increased after orthodontic closure of the diastema (P<0.01). Univariate regression analysis revealed that the PH (P=0.002) and PBT (P=0.047) before orthodontic treatment influenced the alteration of PH. With respect to the alteration of PBT, the diastema width (P=0.045) and PBT (P=0.000) were found to be influential factors. PBT before the orthodontic treatment significantly influenced the alteration of PBT in the multiple regression model. PH decreased but PBT increased after orthodontic closure of the diastema. The papilla dimensions before orthodontic treatment influenced the alterations of PH and PBT after closure of the diastema. The PBT increased more when the diastema width before the orthodontic treatment was larger.
NASA Astrophysics Data System (ADS)
Hu, Liming; Lu, Zhihua; Wang, Biao; Cao, Junsheng; Ma, Xiaobo; Tian, Zhenhua; Gao, Zhijian; Qin, Li; Wu, Xiaodong; Liu, Yun; Wang, Lijun
2011-03-01
Laser welding has the potential to become an effective method for wound closure and healing without sutures. Closure of skin incisions by laser welding with a combination of two near-infrared lasers (980 and 1064 nm), was performed for the first time in this study. One centimeter long, full-thickness incisions were made on the Wistar rat's dorsal skin. The efficiencies of laser-welding with different parameters were investigated. Incision-healing, histology examination, and a tensile strength test of incisions were recorded. Laser welding with the irradiance level of 15.9 W/cm2 for both 980 and 1064-nm lasers and exposure time of 5 s per spot in continuous wave mode yielded a more effective closure and healing with minimal thermal damage, faster recovery, and stronger apposition in comparison with a suturing technique. The conclusion is that skin welding with a combination of two near-infrared diode lasers can be a good candidate for incision closure, and further investigations are in progress for clinical use.
Hu, Liming; Lu, Zhihua; Wang, Biao; Cao, Junsheng; Ma, Xiaobo; Tian, Zhenhua; Gao, Zhijian; Qin, Li; Wu, Xiaodong; Liu, Yun; Wang, Lijun
2011-03-01
Laser welding has the potential to become an effective method for wound closure and healing without sutures. Closure of skin incisions by laser welding with a combination of two near-infrared lasers (980 and 1064 nm), was performed for the first time in this study. One centimeter long, full-thickness incisions were made on the Wistar rat's dorsal skin. The efficiencies of laser-welding with different parameters were investigated. Incision-healing, histology examination, and a tensile strength test of incisions were recorded. Laser welding with the irradiance level of 15.9 W∕cm(2) for both 980 and 1064-nm lasers and exposure time of 5 s per spot in continuous wave mode yielded a more effective closure and healing with minimal thermal damage, faster recovery, and stronger apposition in comparison with a suturing technique. The conclusion is that skin welding with a combination of two near-infrared diode lasers can be a good candidate for incision closure, and further investigations are in progress for clinical use.
Study of relationship between clinical factors and velopharyngeal closure in cleft palate patients
Chen, Qi; Zheng, Qian; Shi, Bing; Yin, Heng; Meng, Tian; Zheng, Guang-ning
2011-01-01
BACKGROUND: This study was carried out to analyze the relationship between clinical factors and velopharyngeal closure (VPC) in cleft palate patients. METHODS: Chi-square test was used to compare the postoperative velopharyngeal closure rate. Logistic regression model was used to analyze independent variables associated with velopharyngeal closure. RESULTS: Difference of postoperative VPC rate in different cleft types, operative ages and surgical techniques was significant (P=0.000). Results of logistic regression analysis suggested that when operative age was beyond deciduous dentition stage, or cleft palate type was complete, or just had undergone a simple palatoplasty without levator veli palatini retropositioning, patients would suffer a higher velopharyngeal insufficiency rate after primary palatal repair. CONCLUSIONS: Cleft type, operative age and surgical technique were the contributing factors influencing VPC rate after primary palatal repair of cleft palate patients. PMID:22279464
Results from extrapleural clipping of a patent ductus arteriosus in seriously ill preterm infants.
Demirturk, Orhan; Güvener, Murat; Coşkun, Isa; Tünel, Hüseyin Ali
2011-12-01
Minithoracotomy for extrapleural closure of the patent ductus arteriosus (PDA) in seriously ill patients offers a fast and less invasive alternative to conventional transpleural ductal closure. This study reports the immediate postoperative clinical outcomes for 24 extrapleurally clipped premature infants presenting with congestive heart failure in high-risk comorbidity status between March 2007 and November 2010. The demographics, preoperative clinical characteristics, and postoperative outcomes of the patients, including echocardiographic assessments, were evaluated. No surgery-related mortalities occurred. Four mortalities occurred after surgery due to sepsis and bleeding diathesis. All 20 surviving patients exhibited normal left ventricular dimensions and systolic function in the immediate follow-up period. The study shows that extrapleural clip closure in seriously ill premature infants has an acceptable overall short-term mortality and complication rate with a high rate of ductal closure.
Liu, Dongbin; Cao, Feng; Liu, Jiafeng; Xu, Dahua; Wang, Yuehua; Li, Fei
2017-01-05
Primary closure following laparoscopic common bile duct exploration (LCBDE) has been widely adopted because of the efficacy and safety in treatment of common bile duct (CBD) stones. However, the risk factors for bile leakage, the most common complication after primary closure, has not been clarified yet. A retrospective cohort study of patients who underwent LCBDE with primary closure after choledochotomy between Feb. 2012 and Jun. 2016 was performed. Risk factors for bile leakage were identified by logistic regression inculding demographic factors, preoperative condition and surgical details. Between Feb. 2012 and Jun. 2016, a total of 265 LCBDE procedures were applied in our hospital and 141 patients with primary closure were included in this study. Bile leakage occurred in 11.3% (16/141) of these patients, and happened more frequently in patients with slender CBD (<1 vs ≥1 cm, 31.6% vs 7.0%, p = 0.04) and those managed by inexperienced surgeons (initial 70 cases vs later cases, 17.1% vs 5.6%, p = 0.04). After multivariable regression, the diameter of CBD [OR 95% CI, 3.799 (1.081-13.349), p = 0.04] and experience of surgeons [OR 95% CI, 4.228 (1.330-13.438), p = 0.03] were significantly related to bile leakage. Slender CBD and inexperienced surgeons were the high risk factors for bile leakage after primary closure following LCBDE.
Column-to-column packing variation of disposable pre-packed columns for protein chromatography.
Schweiger, Susanne; Hinterberger, Stephan; Jungbauer, Alois
2017-12-08
In the biopharmaceutical industry, pre-packed columns are the standard for process development, but they must be qualified before use in experimental studies to confirm the required performance of the packed bed. Column qualification is commonly done by pulse response experiments and depends highly on the experimental testing conditions. Additionally, the peak analysis method, the variation in the 3D packing structure of the bed, and the measurement precision of the workstation influence the outcome of qualification runs. While a full body of literature on these factors is available for HPLC columns, no comparable studies exist for preparative columns for protein chromatography. We quantified the influence of these parameters for commercially available pre-packed and self-packed columns of disposable and non-disposable design. Pulse response experiments were performed on 105 preparative chromatography columns with volumes of 0.2-20ml. The analyte acetone was studied at six different superficial velocities (30, 60, 100, 150, 250 and 500cm/h). The column-to-column packing variation between disposable pre-packed columns of different diameter-length combinations varied by 10-15%, which was acceptable for the intended use. The column-to-column variation cannot be explained by the packing density, but is interpreted as a difference in particle arrangement in the column. Since it was possible to determine differences in the column-to-column performance, we concluded that the columns were well-packed. The measurement precision of the chromatography workstation was independent of the column volume and was in a range of±0.01ml for the first peak moment and±0.007 ml 2 for the second moment. The measurement precision must be considered for small columns in the range of 2ml or less. The efficiency of disposable pre-packed columns was equal or better than that of self-packed columns. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.
McKellar, Stephen H; Deo, Salil; Daly, Richard C; Durham, Lucian A; Joyce, Lyle D; Stulak, John M; Park, Soon J
2014-01-01
A competent aortic valve is essential to providing effective left ventricular assist device support. We have adopted a practice of central aortic valve closure by placing a simple coaptation stitch at left ventricular assist device implantation in patients with significant aortic insufficiency. We conducted a follow-up study to evaluate the efficacy and durability of this procedure. The study included patients who had undergone continuous flow left ventricular assist device implantation. The patients were divided into 2 groups, those who did not require any aortic procedure because the valve was competent and those who underwent central aortic valve closure for mild or greater aortic regurgitation. The clinical endpoints were mortality, progression or recurrence of aortic insufficiency, and reoperation for aortic valve pathologic features. Aortic insufficiency was measured qualitatively from mild to severe on a scale of 0 to 5. A total of 123 patients received continuous flow left ventricular assist devices from February 2007 to August 2011. Of those, 18 (15%) underwent central aortic valve closure at left ventricular assist device implantation because of significant aortic insufficiency (1.8 ± 1.4) and 105 who did not (competent aortic valve, 0.15 ± 0.43; P < .01). At follow-up (median, 312 days; range, 0-1429 days), the mean aortic insufficiency score remained low for the patients with central aortic valve closure (0.27 ± 0.46) in contrast to those without central aortic valve closure who experienced aortic insufficiency progression (0.78 ± 0.89; P = .02). In addition, the proportion of patients with more than mild aortic insufficiency was significantly less in the central aortic valve closure group (0% vs 18%; P = .05). The patients in the central aortic valve closure group were significantly older and had a greater incidence of renal failure at baseline. The 30-day mortality was greater in the central aortic valve closure group, but the late survival was similar between the 2 groups. No reoperations were required for recurrent aortic insufficiency. The results of our study have shown that repair of aortic insufficiency with a simple central coaptation stitch is effective and durable in left ventricular assist device-supported patients, with follow-up extending into 2 years. Although aortic insufficiency progressed over time in those with minimal native valve regurgitation initially, no such progression was noted in those with central aortic valve closure. Additional investigation is needed to evaluate whether prophylactic central aortic valve closure should be performed at left ventricular assist device implantation to avoid problematic aortic regurgitation developing over time, in particular in patients undergoing left ventricular assist device implantation for life-long (destination therapy) support. Copyright © 2014 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Nieuwkerk, D.; Ulrich, R. M.; Paul, J. H.; Hubbard, K.; Kirkpatrick, B. A.; Fanara, T. A.; Bruzek, S.; Hoeglund, A.
2016-02-01
Harmful algal blooms of the dinoflagellate Karenia brevis can cause massive fish-kills and marine mammal mortalities, as well as impact human health via the consumption of brevetoxin-contaminated shellfish and the inhalation of aerosolized toxins. There is a strong effort to predict human health impacts by monitoring the bloom stages of K. brevis, and to prevent health impacts by closing shellfish beds when K. brevis cell concentrations reach toxic levels. The current standard method for quantifying K. brevis is by microscopic enumeration, which requires taxonomic expertise to discern K. brevis cells from other Karenia species as well as a long turnover time to generate data, which limits the number of water samples that can be processed. This EPA-funded study compared a variety of technologies against the current standard (microscopic counts) to quantify the number of K. brevis cells per liter in the water column. Results of this study showed a strong correlation between Real Time Nucleic Acid Sequence-Based Amplification (RT-NASBA) and enumeration by microscopy performed by members of the Florida Fish and Wildlife Research Institute, who are responsible for such monitoring. We are adapting the bench-top RT-NASBA assay to the AmpliFire platform (a handheld sensor that can be used in the field), for point of need K. brevis detection. These handheld sensors will be used by a trained volunteer network and government agencies (FWC, NOAA, and Mote Marine Lab.) to quantify K. brevis cells in the water column of core Gulf of Mexico sites; the results from these sensors will be reported back to the GCOOS observation systems to provide real-time monitoring of K. brevis counts. The real-time information will allow agencies to better monitor fishery closures and predict human health impacts of harmful algal blooms, because a larger number of samples can be processed each week, as the NASBA process removes the rate-limiting step of microscope time.
Agarwal, Shikhar; Bajaj, Navkaranbir Singh; Kumbhani, Dharam J; Tuzcu, E Murat; Kapadia, Samir R
2012-07-01
In this study, a meta-analysis of observational studies was performed to compare the rate of recurrent neurological events (RNE) between transcatheter closure and medical management of patients with cryptogenic stroke/transient ischemic attack (TIA) and concomitant patent foramen ovale (PFO). A significant controversy surrounds the optimal strategy for treatment of cryptogenic stroke/TIA and coexistent PFO. We conducted a MEDLINE search with standard search terms to determine eligible studies. Adjusted incidence rates of RNE were 0.8 (95% confidence interval [CI]: 0.5 to 1.1) events and 5.0 (95% CI: 3.6 to 6.9) events/100 person-years (PY) in the transcatheter closure and medical management arms, respectively. Meta-analysis of the limited number of comparative studies and meta-regression analysis suggested that the transcatheter closure might be superior to the medical therapy in prevention of RNE after cryptogenic stroke. Comparison of the anticoagulation and antiplatelet therapy subgroups of the medical arm yielded a significantly lower risk of RNE within patients treated with anticoagulants. Device-related complications were encountered at the rate of 4.1 (95% CI: 3.2 to 5.0) events/100 PY, with atrial arrhythmias being the most frequent complication. After transcatheter closure, RNE did not seem to be related to the pre-treatment shunt size or the presence of residual shunting in the follow-up period. Significant benefit of transcatheter PFO closure was apparent in elderly patients, patients with concomitant atrial septal aneurysm, and patients with thrombophilia. Rates of RNE with transcatheter closure and medical therapy in patients presenting with cryptogenic stroke or TIA were estimated at 0.8 and 5.0 events/100 PY. Further randomized controlled trials are needed to conclusively compare these 2 management strategies. Copyright © 2012 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
Land use-based landscape planning and restoration in mine closure areas.
Zhang, Jianjun; Fu, Meichen; Hassani, Ferri P; Zeng, Hui; Geng, Yuhuan; Bai, Zhongke
2011-05-01
Landscape planning and restoration in mine closure areas is not only an inevitable choice to sustain mining areas but also an important path to maximize landscape resources and to improve ecological function in mine closure areas. The analysis of the present mine development shows that many mines are unavoidably facing closures in China. This paper analyzes the periodic impact of mining activities on landscapes and then proposes planning concepts and principles. According to the landscape characteristics in mine closure areas, this paper classifies available landscape resources in mine closure areas into the landscape for restoration, for limited restoration and for protection, and then summarizes directions for their uses. This paper establishes the framework of spatial control planning and design of landscape elements from "macro control, medium allocation and micro optimization" for the purpose of managing and using this kind of special landscape resources. Finally, this paper applies the theories and methods to a case study in Wu'an from two aspects: the construction of a sustainable land-use pattern on a large scale and the optimized allocation of typical mine landscape resources on a small scale.
Fleetwood, V A; Gross, K N; Alex, G C; Cortina, C S; Smolevitz, J B; Sarvepalli, S; Bakhsh, S R; Poirier, J; Myers, J A; Singer, M A; Orkin, B A
2017-03-01
Anastomotic leak (AL) increases costs and cancer recurrence. Studies show decreased AL with side-to-side stapled anastomosis (SSA), but none identify risk factors within SSAs. We hypothesized that stapler characteristics and closure technique of the common enterotomy affect AL rates. Retrospective review of bowel SSAs was performed. Data included stapler brand, staple line oversewing, and closure method (handsewn, HC; linear stapler [Barcelona technique], BT; transverse stapler, TX). Primary endpoint was AL. Statistical analysis included Fisher's test and logistic regression. 463 patients were identified, 58.5% BT, 21.2% HC, and 20.3% TX. Covidien staplers comprised 74.9%, Ethicon 18.1%. There were no differences between stapler types (Covidien 5.8%, Ethicon 6.0%). However, AL rates varied by common side closure (BT 3.7% vs. TX 10.6%, p = 0.017), remaining significant on multivariate analysis. Closure method of the common side impacts AL rates. Barcelona technique has fewer leaks than transverse stapled closure. Further prospective evaluation is recommended. Copyright © 2017. Published by Elsevier Inc.
Casson, R J; Newland, H S; Muecke, J; McGovern, S; Abraham, L M; Shein, W K; Selva, D; Aung, T
2007-07-01
To determine the prevalence of preglaucomatous angle-closure disease in central Myanmar. A population-based survey of inhabitants >or=40 years in the Meiktila District was carried out; 2481 subjects were identified, 2076 participated and 2060 underwent gonioscopy of at least one eye. Eyes with angles traditionally described as "occludable" were recorded as primary angle-closure suspects (PACS); eyes with PACS and peripheral anterior synechiae (PAS), or an increased intraocular pressure but without primary angle-closure glaucoma, were recorded as primary angle closure (PAC). The prevalence of PACS in at least one eye was 5.7% (95% CI 4.72 to 6.62); prevalence increased with age and was more common in women (p<0.001). The prevalence of PAC in at least one eye was 1.50% (95% CI 1.47 to 1.53). All participants with PAS had at least 90 degrees of closure (range 90-360 degrees). The prevalence of preglaucomatous angle-closure disease (PACS and PAC) in this population was 5.7% and 1.5%, respectively. PACS was more common in women, and its prevalence increased with age.
NASA Technical Reports Server (NTRS)
Butera, M. K.
1983-01-01
The correlation of canopy closure with the signal response of individual thematic mapper simulator (TMS) bands for selected forest sites in the San Juan National Forest, Colorado was investigated. Ground truth consisted of a photointerpreted determination of percent canopy closure of 0 to 100 percent for 32 sites. The sites selected were situated on plateaus at an elevation of approximately 3 km with slope or = 10 percent. The predominant tree species were ponderosa pine and aspen. The mean TMS response per band per site was calculated from data acquired by aircraft during mid-September, 1981. A correlation analysis of TMS response vs. canopy closure resulted in the following correlation coefficients for bands 1 through 7, respectively: -0.757, -0.663, -0.666, -0.088, -0.797, -0.763. Two model regressions were applied to the TMS data set to create a map of predicted percent forest canopy closure for the study area. Results indicated percent predictive accuracies of 71, 74, and 57 for percent canopy closure classes of 0-25, 25-75, and 75-100, respectively.
NASA Astrophysics Data System (ADS)
Syarif, Andi Erwin; Hatori, Tsuyoshi
2017-06-01
Creating a soft-landing path for mine closure is key to the sustainability of the mining region. In this research, we presents a case of mine closure in Soroako, a small mining town in the north-east of South Sulawesi province, in the center of Sulawesi Island in Indonesia. Especially we investigates corporate social responsibility (CSR) programs of a mining company, PT Vale Indonesia Tbk (PTVI), towards a soft-landing of mine closure in this region. The data of the CSR programs are gathered from in-depth interviews, the annual reports and managerial reports. Furthermore we presents an integrated view of CSR to close mining in a sustainable manner. We then evaluate CSR strategies of the company and its performance from this viewpoint. Based on these steps, the way to improve the CSR mine closure scenario for enhancing the regional sustainability is discussed and recommended.
Procedures adopted by orthodontists for space closure and anchorage control.
Monini, André da Costa; Gandini Júnior, Luiz Gonzaga; dos Santos-Pinto, Ary; Maia, Luiz Guilherme Martins; Rodrigues, Willian Caetano
2013-01-01
The aim of this study was to identify the procedures adopted by Brazilian orthodontists in the following situations: extraction space closure, anchorage control in case of necessary anchorage for group A and frequency of skeletal anchorage use, especially in the upper jaw. A questionnaire was sent to the e-mail address of all dentists registered in the Brazilian Federal Council of Dentistry. The results showed that most Brazilian orthodontists usually perform extraction space closure by means of sliding mechanics. The use of palatal bar, inclusion of second molars in the archwire and space closure performed in two phases are the most used techniques for anchorage control in the upper jaw. The skeletal anchorage is referenced by 36.5% of specialists as a routine practice for the upper arch anchorage. There is a wide variety of procedures adopted by Brazilian orthodontists for orthodontic space closure and anchorage control.
Ectocranial suture closure in Pan troglodytes and Gorilla gorilla: pattern and phylogeny.
Cray, James; Meindl, Richard S; Sherwood, Chet C; Lovejoy, C Owen
2008-08-01
The order in which ectocranial sutures undergo fusion displays species-specific variation among primates. However, the precise relationship between suture closure and phylogenetic affinities is poorly understood. In this study, we used Guttman Scaling to determine if the modal progression of suture closure differs among Homo sapiens, Pan troglodytes, and Gorilla gorilla. Because DNA sequence homologies strongly suggest that P. troglodytes and Homo sapiens share a more recent common ancestor than either does with G. gorilla, we hypothesized that this phylogenetic relationship would be reflected in the suture closure patterns of these three taxa. Results indicated that while all three species do share a similar lateral-anterior closure pattern, G. gorilla exhibits a unique vault pattern, which, unlike humans and P. troglodytes, follows a strong posterior-to-anterior gradient. P. troglodytes is therefore more like Homo sapiens in suture synostosis. Copyright 2008 Wiley-Liss, Inc.
Program closure and change among VA substance abuse treatment programs.
Floyd, A S
1999-10-01
The population of Veterans Affairs (VA) substance abuse treatment programs in 1990 and 1994 was examined to determine which factors-program legitimacy or cost-accounted for program closure and change. Legitimacy is a concept in institutional theory that organizations tend to take on a form appropriate to the environment. The study had two competing hypotheses. The first was that if external pressures push programs to produce high-quality and efficient treatment, then those that are initially closer to the legitimate form should be less likely to close later, and among surviving programs they should be less likely to experience change. The second hypothesis was that cost is the primary factor in program closure and change. The study used data from administrative surveys of all VA programs (273 in 1990 and 389 in 1994). Program legitimacy variables measured whether programs offered the prevalent type of treatment, such as 12-step groups or behavioral treatment, and had the prevalent type of staff. Program costs did not explain closure or change. For inpatient programs, the risk of closure increased in facilities with more than one substance abuse treatment program. The risk of closure increased for outpatient programs offering the prevalent type of treatment, contrary to what was predicted by the legitimacy hypothesis. Inpatient programs that offered the prevalent treatment were less likely to change the type of treatment offered. Patterns of change differed over time for inpatient and outpatient programs. Legitimacy factors, rather than cost, seem to play a role in program closure and change, although the picture is clearer for inpatient programs than for outpatient programs.
Huahui, Zhang; Dan, Xue; Hongfei, Jiang; Hang, Hu; Chunmao, Han; Haitao, Ren; Jianxin, Yu; Zhiping, Tao
2016-01-01
BACKGROUND Wounds that have been closed under excessive tension, and skin defects that cannot be closed primarily, pose a daily challenge for the reconstructive surgeon. OBJECTIVE To evaluate a new tension relief system (TRS) device for skin stretching and secure wound closure. METHODS From September 2013 to March 2014, a consecutive series of 41 Chinese patients with 43 wounds were enrolled for application of 50 cycles of TRS therapy. TRS was used for two main clinical applications: closure of a variety of surgical/traumatic wounds; and securing wound closure after high-tension suture closure. Basic information and details regarding this therapy and its complications were recorded. Follow-up visits were conducted three to six months after wound closure. RESULTS Mean residual wound width decreased approximately 20% every two days during cycles of TRS therapy. Infection was the most common complication (five cases). Other complications included dehiscence (two cases) and pressure ulcer (one case). At the six-month follow-up visit, (21 wounds in 20 patients), both the extent of healing and the scar were acceptable. DISCUSSION There are no absolute contraindications to TRS therapy. The authors have formulated instructions for the prevention and treatment of the most common complications. CONCLUSIONS The results demonstrate that TRS therapy is a simple, effective method for primary closure of difficult wounds, and large skin and soft-tissue defects. Larger randomized studies are required to further evaluate of the effectiveness, indications, complications and cost effectiveness of this innovative TRS therapy. PMID:28439506
Djer, Mulyadi M; Saputro, Dimas Dwi; Putra, Sukman Tulus; Idris, Nikmah Salamia
2015-06-01
Transcatheter closure of patent ductus arteriosus (PDA) has been suggested to be the standard treatment of PDA. Although, in general, the procedure shows a high successful rate, outcomes may vary among pediatric cardiology centers. To evaluate the effectiveness of transcatheter closure of PDA in Cipto Mangunkusumo Hospital, Jakarta, Indonesia, this was a retrospective study on patients who underwent transcatheter closure of PDA in Cipto Mangunkusumo Hospital during the period of 2002-2013. Hospital registry was reviewed and data about patients' characteristics, PDA severity, procedure, and outcomes were retrieved. There were 298 patients, of whom 90 were males, who underwent transcatheter closure of PDA during the study period. Median age was 3.4 years (1 months-18 years), and median body weight was 12 (3.6-59) kg. The diameter of PDA ranged from 1.1 to 15.4 mm with a median of 3.7 mm. Device could be deployed in all patients, in which most were the Amplatzer ductal occluder (69.8 %) and the remainders were coils. Median fluoroscopy time was 15.4 (1.5-87) min, and procedure time was 76 (30-200) min. Complete closure was achieved in most patients (97.3 %), whereas device migration occurred in a minority (0.3 %) of patients. No major complication occurred during or after the procedure. Transient anemia and bradycardia were found in 3.7 and 1.3 % patients, respectively. Most patients were discharged from the hospital at 1 day after the procedure. Transcatheter closure method is a safe and effective procedure to close PDA.
Oral Paracetamol for Patent Ductus Arteriosus Rescue Closure.
Pharande, Pramod; Watson, Hadley; Tan, Kenneth; Sehgal, Arvind
2018-01-01
The objective of this study was to ascertain the efficacy of oral paracetamol in closing a symptomatic patent ductus arteriosus (PDA) when used as 'rescue' option. After obtaining ethics approval, a retrospective appraisal of the data from April 2014 to July 2015 was performed. Infants who were administered oral paracetamol either after unsuccessful therapy with ibuprofen or where it was considered contraindicated were included. A previously published echocardiographic scoring schema to stratify for ductal disease severity was used. Using univariate analysis, characteristics of infants with successful closure were compared with partial (a priori reduction in composite score by ≥ 50% of pretreatment) or no closure. Twenty infants with gestation age and birthweight of 25.7 ± 1.5 weeks and 724.1 ± 143 g, respectively, were studied. Complete closure was noted in 10 (50%) infants with additional four infants showing a significant reduction in haemodynamic shunting. Gestational age at birth and at therapy, chronological age at therapy, birthweight and total fluid intake were comparable between the two groups. The pre-therapy composite score had a significant association with successful closure (the higher the echocardiographic score, the lesser the closure). Concomitant furosemide therapy and late-onset sepsis had a high likelihood ratio of unsuccessful closure (11.01 [2-tailed, p = 0.005] and 5.3 [2-tailed, p = 0.07]), respectively. Oral paracetamol may be a possible therapeutic option in premature infants where therapy with first-line agents is unsuccessful or contraindicated. Concomitant sepsis and furosemide administration may affect successful therapy.
Laaniste, Asko; Kruve, Anneli; Leito, Ivo
2013-08-01
Two different methods to reinforce the poly(glycidyl methacrylate-co-ethylene dimethacrylate) HPLC monolithic columns of 3 mm id in a glass column reservoir were studied: composite columns with polymeric particles in the monolith and surface treatment of the reservoir wall. Of the two methods used to counter the mechanical instability and formation of flow channels (composite columns and column wall surface treatment), we demonstrated that proper column wall surface treatment was sufficient to solve both problems. Our study also indicated that no surface treatment is efficient, and of the methods studied silanization in acidified ethanol solution and constant renewal of the reaction mixture (dynamic mode) proved to be the most effective. As a result of this study, we have been able to prepare repeatable and durable methacrylate HPLC columns with good efficiencies. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Reddy, Vivek Y; Möbius-Winkler, Sven; Miller, Marc A; Neuzil, Petr; Schuler, Gerhard; Wiebe, Jens; Sick, Peter; Sievert, Horst
2013-06-25
The purpose of this study was to assess the safety and efficacy of left atrial appendage (LAA) closure in nonvalvular atrial fibrillation (AF) patients ineligible for warfarin therapy. The PROTECT AF (Watchman Left Atrial Appendage System for Embolic Protection in Patients With Atrial Fibrillation) trial demonstrated that LAA closure with the Watchman device (Boston Scientific, Natick, Massachusetts) was noninferior to warfarin therapy. However, the PROTECT AF trial only included patients who were candidates for warfarin, and even patients randomly assigned to the LAA closure arm received concomitant warfarin for 6 weeks after Watchman implantation. A multicenter, prospective, nonrandomized study was conducted of LAA closure with the Watchman device in 150 patients with nonvalvular AF and CHADS₂ (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, and prior stroke or transient ischemic attack) score ≥1, who were considered ineligible for warfarin. The primary efficacy endpoint was the combined events of ischemic stroke, hemorrhagic stroke, systemic embolism, and cardiovascular/unexplained death. The mean CHADS₂ score and CHA₂DS₂-VASc (CHADS₂ score plus 2 points for age ≥75 years and 1 point for vascular disease, age 65 to 74 years, or female sex) score were 2.8 ± 1.2 and 4.4 ± 1.7, respectively. History of hemorrhagic/bleeding tendencies (93%) was the most common reason for warfarin ineligibility. Mean duration of follow-up was 14.4 ± 8.6 months. Serious procedure- or device-related safety events occurred in 8.7% of patients (13 of 150 patients). All-cause stroke or systemic embolism occurred in 4 patients (2.3% per year): ischemic stroke in 3 patients (1.7% per year) and hemorrhagic stroke in 1 patient (0.6% per year). This ischemic stroke rate was less than that expected (7.3% per year) based on the CHADS₂ scores of the patient cohort. LAA closure with the Watchman device can be safely performed without a warfarin transition, and is a reasonable alternative to consider for patients at high risk for stroke but with contraindications to systemic oral anticoagulation. (ASA Plavix Feasibility Study With Watchman Left Atrial Appendage Closure Technology [ASAP]; NCT00851578). Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
Variation in stop consonant voicing in two regional varieties of American English
Jacewicz, Ewa; Fox, Robert Allen; Lyle, Samantha
2010-01-01
This study is an acoustic investigation of the nature and extent of consonant voicing of the stop /b/ in two dialectal varieties of American English spoken in south-central Wisconsin and western North Carolina. The stop /b/ occurred at the juncture of two words such as small bids, in a position between two voiced sonorants, i.e. the liquid /l/ and a vowel. Twenty women participated, ten representing the Wisconsin and ten the North Carolina variety, respectively. Significant dialectal differences were found in the voicing patterns. The Wisconsin stop closures were usually not fully voiced and terminated in a complete silence followed by a closure release whereas North Carolina speakers produced mostly fully voiced closures. Further dialectal differences included the proportion of closure voicing as a function of word emphasis. For Wisconsin speakers, the proportion of closure voicing was smallest when the word was emphasized and it was greatest in non-emphatic positions. For North Carolina speakers, the degree of word emphasis did not have an effect on the proportion of closure voicing. The results suggest different mechanisms by which closure voicing is maintained in these two dialects, pointing to active articulatory maneuvers in North Carolina speakers and passive in Wisconsin speakers. PMID:20198112
Landry, Nicholas W.; Knezevic, Marko
2015-01-01
Property closures are envelopes representing the complete set of theoretically feasible macroscopic property combinations for a given material system. In this paper, we present a computational procedure based on fast Fourier transforms (FFTs) for delineation of elastic property closures for hexagonal close packed (HCP) metals. The procedure consists of building a database of non-zero Fourier transforms for each component of the elastic stiffness tensor, calculating the Fourier transforms of orientation distribution functions (ODFs), and calculating the ODF-to-elastic property bounds in the Fourier space. In earlier studies, HCP closures were computed using the generalized spherical harmonics (GSH) representation and an assumption of orthotropic sample symmetry; here, the FFT approach allowed us to successfully calculate the closures for a range of HCP metals without invoking any sample symmetry assumption. The methodology presented here facilitates for the first time computation of property closures involving normal-shear coupling stiffness coefficients. We found that the representation of these property linkages using FFTs need more terms compared to GSH representations. However, the use of FFT representations reduces the computational time involved in producing the property closures due to the use of fast FFT algorithms. Moreover, FFT algorithms are readily available as opposed to GSH codes. PMID:28793566
To close or not to close: contemporary indications for patent foramen ovale closure.
Zier, Lucas S; Sievert, Horst; Mahadevan, Vaikom S
2016-11-01
Patent foramen ovale (PFO) is a common congenital cardiac abnormality and that has been associated with several disease processes including transient ischemic attacks (TIA), stroke, migraine headaches with aura, decompression sickness, platypnea-orthodeoxia syndrome, and shunt induced cyanosis. Controversy exists regarding closure of PFO as a therapeutic treatment modality for these disease processes. This review addresses the contemporary clinical indications for PFO closure. Areas covered: We conducted a comprehensive literature search of contemporary research studies focusing on randomized trials and meta-analyses comparing medical therapy and device closure of PFOs for the treatment of PFO associated clinical syndromes. We synthesized this literature into a review addressing indications for PFO closure in stroke, TIA, migraine headaches with aura, decompression sickness, platypnea-orthodeoxia syndrome, and shunt induced cyanosis. Expert commentary: Because in many PFO associated conditions it can be difficult to determine the degree to which the PFO is a causative factor in the disease process, we recommend a comprehensive diagnostic evaluation to exclude other obvious etiologies of PFO associated conditions before implicating the PFO and proceeding with closure. However in the properly selected patient population there is growing clinical experience and experimental evidence suggesting that closure of PFO is a safe and effective treatment modality.
Walker, Kara Odom; Calmes, Daphne; Hanna, Nancy; Baker, Richard
2010-01-01
Background Challenges around safety-net hospital closure have impacted medical student and resident exposure to urban public healthcare sites that may influence their future practice choices. Objective To assess the impact of the closure of a public safety-net teaching hospital for the clinical medical education of Charles Drew University medical students and residents. Method Retrospective cohort study of medical students’ and residents’ and clinical placement into safety-net experiences after the closure of the primary teaching hospital. Results The hospital closure impacted both medical student and residency training experiences. Only 71% (17/24) of medical student rotations and 13% (23/180) of residents were maintained at public safety-net clinical sittings. The closure of the public safety-net hospital resulted in the loss of 36% of residency training spots sponsored by historically black medical schools in the United States and an even larger negative impact on the number of physicians training in underserved urban areas of Los Angeles County. Conclusion While the medical educational program changes undertaken in the wake of hospital closure have negatively affected the immediate clinical educational experiences of medical students and residents, it remains to be seen whether the training site location changes will alter their long-term preferences in specialty choice and practice location. PMID:19110905
Walker, Kara Odom; Calmes, Daphne; Hanna, Nancy; Baker, Richard
2008-12-01
Challenges around safety-net hospital closure have impacted medical student and resident exposure to urban public healthcare sites that may influence their future practice choices. To assess the impact of the closure of a public safety-net teaching hospital for the clinical medical education of Charles Drew University medical students and residents. Retrospective cohort study of medical students' and residents' and clinical placement into safety-net experiences after the closure of the primary teaching hospital. The hospital closure impacted both medical student and residency training experiences. Only 71% (17/24) of medical student rotations and 13% (23/180) of residents were maintained at public safety-net clinical sittings. The closure of the public safety-net hospital resulted in the loss of 36% of residency training spots sponsored by historically black medical schools in the United States and an even larger negative impact on the number of physicians training in underserved urban areas of Los Angeles County. While the medical educational program changes undertaken in the wake of hospital closure have negatively affected the immediate clinical educational experiences of medical students and residents, it remains to be seen whether the training site location changes will alter their long-term preferences in specialty choice and practice location.
Prediction of axial limit capacity of stone columns using dimensional analysis
NASA Astrophysics Data System (ADS)
Nazaruddin A., T.; Mohamed, Zainab; Mohd Azizul, L.; Hafez M., A.
2017-08-01
Stone column is the most favorable method used by engineers in designing work for stabilization of soft ground for road embankment, and foundation for liquid structure. Easy installation and cheaper cost are among the factors that make stone column more preferable than other method. Furthermore, stone column also can acts as vertical drain to increase the rate of consolidation during preloading stage before construction work started. According to previous studied there are several parameters that influence the capacity of stone column. Among of them are angle friction of among the stones, arrangement of column (two pattern arrangement most applied triangular and square), spacing center to center between columns, shear strength of soil, and physical size of column (diameter and length). Dimensional analysis method (Buckingham-Pi Theorem) has used to carry out the new formula for prediction of load capacity stone columns. Experimental data from two previous studies was used for analysis of study.
Closure properties of Watson-Crick grammars
NASA Astrophysics Data System (ADS)
Zulkufli, Nurul Liyana binti Mohamad; Turaev, Sherzod; Tamrin, Mohd Izzuddin Mohd; Azeddine, Messikh
2015-12-01
In this paper, we define Watson-Crick context-free grammars, as an extension of Watson-Crick regular grammars and Watson-Crick linear grammars with context-free grammar rules. We show the relation of Watson-Crick (regular and linear) grammars to the sticker systems, and study some of the important closure properties of the Watson-Crick grammars. We establish that the Watson-Crick regular grammars are closed under almost all of the main closure operations, while the differences between other Watson-Crick grammars with their corresponding Chomsky grammars depend on the computational power of the Watson-Crick grammars which still need to be studied.
Association of land use and its change with beach closure in ...
Land use and its change have great influences on water quality. However, their impacts on microbial contamination of beach water have been rarely investigated and their relationship with beach closure is still unknown. Here, we analyzed beach closure data obtained from 2004 to 2013 for more than 500 beaches in the United States, and examined their associations with land use around beaches in 2006 and 2011, respectively, as well as the land use change between 2011 and 2006. The results show that the number of beach closures is negatively associated with the percentages of forest, barren land, grassland and wetland, while positively associated with the percentage of urban area. The results from multi-level models also indicate the negative association with forest area but positive association with urban area and agriculture. The examination of the change of land use and the number of beach closures between 2011 and 2006 indicates that the increase in the number of beach closures is positively associated with the increase in urban (β=1.612, p<0.05) and agricultural area including pasture (β=0.098, p<0.05), but negatively associated with the increase in forest area (β= -1.789, p<0.05). The study suggests that urbanization and agriculture development near beaches have adverse effects on beach microbial water quality, while afforestation may protect beach water quality and reduce the number of beach closures. To compare differences in beach closures across the US u
Guedes, Renata; Azola, Alba; Macrae, Phoebe; Sunday, Kirstyn; Mejia, Veerley; Vose, Alicia; Humbert, Ianessa A.
2017-01-01
Swallowing maneuvers are routinely trained in dysphagia rehabilitation with the assumption that practiced behaviors transfer to functional swallowing, however transfer is rarely examined in the deglutition literature. The goal of this study was to train the volitional laryngeal vestibule closure (vLVC) maneuver, which is a swallowing maneuver that targets prolonged laryngeal vestibule closure (LVC). In two different training experiments, 69 healthy adults underwent Long-hold (hold vLVC as long as possible) or Short-hold vLVC training (hold vLVC for 2 seconds). Before and after vLVC training, natural swallows (swallowing without a therapeutic technique) were completed. The outcome variables included laryngeal vestibule closure reaction time and the duration of laryngeal vestibule closure. Results indicate that during both Long-hold and Short-hold vLVC trainings, vLVC swallows had faster laryngeal vestibule closure reaction times and longer durations of laryngeal vestibule closure than in pre-training 5ml liquid swallows. However, only faster laryngeal vestibule closure reaction times transferred to post-training 5ml liquid swallows (20–24% faster), but not prolonged durations of laryngeal vestibule closure. Our findings suggest that swallowing maneuver training has the potential to induce transfer of what was practiced to functional swallowing behavior, although not all practiced behaviors may generalize. These findings are significant for bolstering the effectiveness of dysphagia management medical settings and should be tested in individuals with dysphagia. PMID:28322908
Muzaffar, Iqbal; Zula, Pai; Yimit, Yusp; Jaan, Ajim Tuergan; Wen, Hao
2014-11-01
To compare the postoperative short-term and mid-term complications in patients who underwent CBD exploration and closure by using T-tube or primary closure. Prospective randomized clinical trial. Hepatobiliary Department of First Affiliated Hospital of Xinjiang Medical University, Urumqi, China, from August 2009 to March 2013. A total of 148 consecutive patients with Common Bile Duct Stones (CBDS) and CBD dilation were enrolled in this randomized study to undergo open cholecystectomy with CBD exploration. Pre-operative findings, postoperative short-term complications, postoperative follow-up (mid-term), and hospital stay were recorded and analyzed. A T-tube was inserted in 76 (51.35%) patients and the primary closure was done in 72 (48.64%) patients. There were no differences in the demographic characteristics and clinical presentations between the two groups. Compared with the T-tube group 8.97 ± 1.629 days, the postoperative stay in primary closure 5.34 ± 1.25 days was significantly shorter (p < 0.01). The incidence of overall postoperative short-term complications and mid-term complications were statistically but not significantly lower in the primary closure group (9.7%) than that in T-tube group (17.10%, p=0.189). Complications in the primary closure group were lower than that in T-tube group but there was no significant statistical difference. So during open surgery for CBD stones, primary closure of CBD appeared safe and effective with shorter hospital stays and less complications.
Hamabe, L; Kim, S; Yoshiyuki, R; Fukayama, T; Nakata, T M; Fukushima, R; Tanaka, R
2015-01-01
Closure of PDA can be associated with echocardiographic changes including deterioration of LV systolic function. Although PDA is commonly encountered in dogs, few comprehensive reports of echocardiographic changes in dogs with PDA closure are available. To evaluate the short-term echocardiographic changes observed after PDA closure in dogs using strain analysis. Seventeen client-owned dogs with left-to-right PDA. Echocardiographic evaluations, including standard echocardiography and two-dimensional tissue tracking (2DTT), were performed before and within 3 days of PDA closure. Preclosure examination showed LV and left atrial dilatation indicating volume overload as a result of PDA. Closure of PDA resulted in significant reduction of LVIDd (<.0001) and LA/Ao (0.01) without change in LVIDs, suggestive of decreased preload. Postclosure LV systolic dysfunction was observed with significant decreased in FS (<.0001) and strain values (P = .0039 for radial strains, P = .0005 for circumferential strains). Additionally, significant LV dyssynchrony (P = .0162) was observed after closure of PDA. Closure of PDA resulted in decreased preload as a result of alleviation of LV volume overload, which in turn caused transient deterioration of LV systolic function. Additionally, this study demonstrated that strain analysis is load dependent. Therefore, care should be taken when interpreting strain measurements as an indicator of LV systolic function. Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of American College of Veterinary Internal Medicine.
Guedes, Renata; Azola, Alba; Macrae, Phoebe; Sunday, Kirstyn; Mejia, Veerley; Vose, Alicia; Humbert, Ianessa A
2017-05-15
Swallowing maneuvers are routinely trained in dysphagia rehabilitation with the assumption that practiced behaviors transfer to functional swallowing, however transfer is rarely examined in the deglutition literature. The goal of this study was to train the volitional laryngeal vestibule closure (vLVC) maneuver, which is a swallowing maneuver that targets prolonged laryngeal vestibule closure (LVC). In two different training experiments, 69 healthy adults underwent Long-hold (hold vLVC as long as possible) or Short-hold vLVC training (hold vLVC for 2s). Before and after vLVC training, natural swallows (swallowing without a therapeutic technique) were completed. The outcome variables included laryngeal vestibule closure reaction time and the duration of laryngeal vestibule closure. Results indicate that during both Long-hold and Short-hold vLVC trainings, vLVC swallows had faster laryngeal vestibule closure reaction times and longer durations of laryngeal vestibule closure than in pre-training 5ml liquid swallows. However, only faster laryngeal vestibule closure reaction times transferred to post-training 5ml liquid swallows (20-24% faster), but not prolonged durations of laryngeal vestibule closure. Our findings suggest that swallowing maneuver training has the potential to induce transfer of what was practiced to functional swallowing behavior, although not all practiced behaviors may generalize. These findings are significant for bolstering the effectiveness of dysphagia management in medical settings and should be tested in individuals with dysphagia. Copyright © 2017 Elsevier Inc. All rights reserved.
Anatomy of the patent foramen ovale for the interventionalist.
McKenzie, Jeff A; Edwards, William D; Hagler, Donald J
2009-05-01
Patent foramen ovale (PFO) is an interatrial communication whose management is controversial. Several manufacturers have submitted protocols for Food and Drug Administration (FDA) approval of their PFO closure device. The purpose of this study was to define anatomy relevant to percutaneous PFO closure, validate the clinical observation that most PFOs contain little tissue rim at the aorta, comment on proposed closure guidelines, and to discuss approaches to PFO closure. From the Mayo Clinic Tissue Registry, five normal hearts with PFO were selected from each sex from the first 10 decades of life (n = 100). Measurements (mm) included PFO length, diameter, and distance from FO-superior vena cava (SVC) and FO-aortic annulus (AoAn). Patient age, weight, and height were obtained from autopsy reports, and body surface area (BSA) was calculated. PFO length and diameter increased with age (P = 0.029 and 0.001, respectively), and FO-SVC and FO-AoAn increased with BSA (P
Cleft Palate Fistula Closure Utilizing Acellular Dermal Matrix.
Emodi, Omri; Ginini, Jiriys George; van Aalst, John A; Shilo, Dekel; Naddaf, Raja; Aizenbud, Dror; Rachmiel, Adi
2018-03-01
Fistulas represent failure of cleft palate repair. Secondary and tertiary fistula repair is challenging, with high recurrence rates. In the present retrospective study, we review the efficacy of using acellular dermal matrix as an interposition layer for cleft palate fistula closure in 20 consecutive patients between 2013 and 2016. Complete fistula closure was obtained in 16 patients; 1 patient had asymptomatic recurrent fistula; 2 patients had partial closure with reduction of fistula size and minimal nasal regurgitation; 1 patient developed a recurrent fistula without changes in symptoms (success rate of 85%). We conclude that utilizing acellular dermal matrix for cleft palate fistula repair is safe and simple with a high success rate.
Cleft Palate Fistula Closure Utilizing Acellular Dermal Matrix
Emodi, Omri; van Aalst, John A.; Shilo, Dekel; Naddaf, Raja; Aizenbud, Dror; Rachmiel, Adi
2018-01-01
Summary: Fistulas represent failure of cleft palate repair. Secondary and tertiary fistula repair is challenging, with high recurrence rates. In the present retrospective study, we review the efficacy of using acellular dermal matrix as an interposition layer for cleft palate fistula closure in 20 consecutive patients between 2013 and 2016. Complete fistula closure was obtained in 16 patients; 1 patient had asymptomatic recurrent fistula; 2 patients had partial closure with reduction of fistula size and minimal nasal regurgitation; 1 patient developed a recurrent fistula without changes in symptoms (success rate of 85%). We conclude that utilizing acellular dermal matrix for cleft palate fistula repair is safe and simple with a high success rate. PMID:29707449
Software Review: A program for testing capture-recapture data for closure
Stanley, Thomas R.; Richards, Jon D.
2005-01-01
Capture-recapture methods are widely used to estimate population parameters of free-ranging animals. Closed-population capture-recapture models, which assume there are no additions to or losses from the population over the period of study (i.e., the closure assumption), are preferred for population estimation over the open-population models, which do not assume closure, because heterogeneity in detection probabilities can be accounted for and this improves estimates. In this paper we introduce CloseTest, a new Microsoft® Windows-based program that computes the Otis et al. (1978) and Stanley and Burnham (1999) closure tests for capture-recapture data sets. Information on CloseTest features and where to obtain the program are provided.
Hospital closure: a review of current and proposed research.
Hernandez, S R; Kaluzny, A D
1983-01-01
This paper reviews available data describing issues and research findings with implications for hospital closings. Factors contributing to fiscal problems of hospitals (e.g., inadequate reimbursement, inflation, management problems, organizational structure, societal factors) are discussed. Selected studies offering examples of hospital and community characteristics associated with closure are presented. This review suggests that future directions for research should focus not only on hospital cost control but also on insuring equity in the distribution of hospital services. Specifically, research is needed that further describes the hospital closure phenomenon, the effects of closure, and the policy choices that might be pursued to insure equity in the continuation of hospital services to disadvantaged populations. PMID:6360954
A design procedure for a tension-wire stiffened truss-column
NASA Technical Reports Server (NTRS)
Greene, W. H.
1980-01-01
A deployable, tension wire stiffened, truss column configuration was considered for space structure applications. An analytical procedure, developed for design of the truss column and exercised in numerical studies, was based on equivalent beam stiffness coefficients in the classical analysis for an initially imperfect beam column. Failure constraints were formulated to be used in a combined weight/strength and nonlinear mathematical programming automated design procedure to determine the minimum mass column for a particular combination of design load and length. Numerical studies gave the mass characteristics of the truss column for broad ranges of load and length. Comparisons of the truss column with a baseline tubular column used a special structural efficiency parameter for this class of columns.
NASA Technical Reports Server (NTRS)
Lundquist, Eugene E; Rossman, Carl A; Houbolt, John C
1943-01-01
The results are presented of a theoretical study for the determination of the column curve from tests of column specimens having ends equally restrained against rotation. The theory of this problem is studied and a curve is shown relating the fixity coefficient c to the critical load, the length of the column, and the magnitude of the elastic restraint. A method of using this curve for the determination of the column curve for columns with pin ends from tests of columns with elastically restrained ends is presented. The results of the method as applied to a series of tests on thin-strip columns of stainless steel are also given.
Nelken, N; Lewis, F
1989-01-01
The management of penetrating colon injury has been frequently debated in the literature, yet few reports have evaluated primary closure versus diverting colostomy in similarly injured patients. Diverting colostomy is the standard of care when mucosal penetration is present, but primary closure in civilian practice has generally had excellent results, although it has been restricted to less severely injured patients. Because the degree of injury may influence choice of treatment in modern practice, various indices of injury severity have been proposed for assessment of patients with penetrating colon trauma. As yet, however, there has been no cross-comparison of repair type versus injury severity. A retrospective study 76 patients who sustained penetrating colon trauma between January 1, 1979 and December 31, 1985 and who survived for at least 24 hours was conducted. Different preferences among attending surgeons and a more aggressive approach to the use of primary closure during the years of study led to an essentially random use of primary closure and diverting colostomy for moderate levels of colon injury, with mandatory colostomy reserved for the most serious injuries. Primary closure was performed in 37 patients (three having resection and anastomosis), and colostomy was performed in 39 patients. Severity of injury was evaluated by the Injury Severity Score (ISS), Penetrating Abdominal Trauma Index (PATI), and the Flint Colon Injury Score. Complications and outcome were evaluated as a function of severity of injury, and primary closure and colostomy were compared. Demographic profiles of the two groups did not differ regarding age, sex, mechanism of injury, shock, or delay between injury and operation. The mortality rate was 2.6% for each group. Major morbidity, including septic complications, occurred in 11% of the patients of the primary closure group and in 49% of those of the colostomy group. When PATI was less than 25, the Flint score was less than or equal to 2, or when the ISS was less than 25, primary closure resulted in fewer complications than did colostomy. Of the injury severity indices examined, the PATI most reliably predicted complications and specifically identified patients who whose outcome would be good with primary repair. These results suggest that the use of primary closure should be expanded in civilian penetrating colon trauma and that, even with moderate degrees of colon injury, primary closure provides an outcome equivalent to that provided by colostomy. In addition, the predictive value of the PATI suggests that it should be included along with other injury severity indices in trauma data bases. Images Fig. 3. Fig. 4. PMID:2930290
NASA Technical Reports Server (NTRS)
Xu, Kuan-Man
1994-01-01
Simulated data from the UCLA cumulus ensemble model are used to investigate the quasi-universal validity of closure assumptions used in existing cumulus parameterizations. A closure assumption is quasi-universally valid if it is sensitive neither to convective cloud regimes nor to horizontal resolutions of large-scale/mesoscale models. The dependency of three types of closure assumptions, as classified by Arakawa and Chen, on the horizontal resolution is addressed in this study. Type I is the constraint on the coupling of the time tendencies of large-scale temperature and water vapor mixing ratio. Type II is the constraint on the coupling of cumulus heating and cumulus drying. Type III is a direct constraint on the intensity of a cumulus ensemble. The macroscopic behavior of simulated cumulus convection is first compared with the observed behavior in view of Type I and Type II closure assumptions using 'quick-look' and canonical correlation analyses. It is found that they are statistically similar to each other. The three types of closure assumptions are further examined with simulated data averaged over selected subdomain sizes ranging from 64 to 512 km. It is found that the dependency of Type I and Type II closure assumptions on the horizontal resolution is very weak and that Type III closure assumption is somewhat dependent upon the horizontal resolution. The influences of convective and mesoscale processes on the closure assumptions are also addressed by comparing the structures of canonical components with the corresponding vertical profiles in the convective and stratiform regions of cumulus ensembles analyzed directly from simulated data. The implication of these results for cumulus parameterization is discussed.
Impact of High Seas Closure on Food Security in Low Income Fish Dependent Countries
Teh, Louise S. L.; Lam, Vicky W. Y.; Cheung, William W. L.; Miller, Dana; Teh, Lydia C. L.; Sumaila, U. Rashid
2016-01-01
We investigate how high seas closure will affect the availability of commonly consumed food fish in 46 fish reliant, and/or low income countries. Domestic consumption of straddling fish species (fish that would be affected by high seas closure) occurred in 54% of the assessed countries. The majority (70%) of countries were projected to experience net catch gains following high seas closure. However, countries with projected catch gains and that also consumed the straddling fish species domestically made up only 37% of the assessed countries. In contrast, much fewer countries (25%) were projected to incur net losses from high seas closure, and of these, straddling species were used domestically in less than half (45%) of the countries. Our findings suggest that, given the current consumption patterns of straddling species, high seas closure may only directly benefit the supply of domestically consumed food fish in a small number of fish reliant and/or low income countries. In particular, it may not have a substantial impact on improving domestic fish supply in countries with the greatest need for improved access to affordable fish, as only one third of this group used straddling fish species domestically. Also, food security in countries with projected net catch gains but where straddling fish species are not consumed domestically may still benefit indirectly via economic activities arising from the increased availability of non-domestically consumed straddling fish species following high seas closure. Consequently, this study suggests that high seas closure can potentially improve marine resource sustainability as well as contribute to human well-being in some of the poorest and most fish dependent countries worldwide. However, caution is required because high seas closure may also negatively affect fish availability in countries that are already impoverished and fish insecure. PMID:28033359
Transverse closure of mesenterico-portal vein after vein resection in pancreatoduodenectomy.
Chua, T C; de Reuver, P R; Staerkle, R F; Neale, M L; Arena, J; Mittal, A; Shanbhag, S T; Gill, A J; Samra, J S
2016-02-01
Resection of the involved mesenteric-portal vein (MPV) is increasingly performed in pancreatoduodenectomy. The primary aim of this study is to assess the rate of R0 resection in transverse closure (TC) versus segmental resection with end-to-end (EE) closure and the secondary aims are to assess the short-term morbidity and long-term survival of TC versus EE. Patients undergoing pancreatoduodenectomy with MPV resection were identified from a prospectively database. The reconstruction technique were examined and categorized. Clinical, pathological, short-term and long-term survival outcomes were compared between groups. 110 patients underwent PD with MPV resection of which reconstruction was performed with an end-to-end technique in 92 patients (84%) and transverse closure technique in 18 patients (16%). Patients undergoing transverse closure tended to have had a shorter segment of vein resected (≤2 cm) compared to the end-to-end (83% vs. 43%; P = 0.004) with no difference in R0 rate. Short-term morbidity was similar. The median and 5-year survival was 30.0 months and 18% respectively for patients undergoing transverse closure and 28.6 months and 7% respectively for patients undergoing end-to-end reconstruction (P = 0.766). Without compromising the R0 rate, transverse closure to reconstruct the mesenteric-portal vein is shown to be feasible and safe in the setting when a short segment of vein resection is required during pancreatoduodenectomy. Synopsis - We describe a vein closure technique, transverse closure, which avoids the need for a graft, or re-implantation of the splenic vein when resection of the mesenteric-portal vein confluence is required during pancreatoduodenectomy. Copyright © 2015 Elsevier Ltd. All rights reserved.
Serrano, Katherine; Levin, Elena; Culibrk, Brankica; Weiss, Sandra; Scammell, Ken; Boecker, Wolfgang F; Devine, Dana V
2010-01-01
BACKGROUND In high-volume processing environments, manual breakage of in-line closures can result in repetitive strain injury (RSI). Furthermore, these closures may be incorrectly opened causing shear-induced hemolysis. To overcome the variability of in-line closure use and minimize RSI, Fresenius Kabi developed a new in-line closure, the CompoFlow, with mechanical openers. STUDY DESIGN AND METHODS The consistency of the performance of the CompoFlow closure device was assessed, as was its effect on component quality. A total of 188 RBC units using CompoFlow blood bag systems and 43 using the standard bag systems were produced using the buffy coat manufacturing method. Twenty-six CompoFlow platelet (PLT) concentrates and 10 control concentrates were prepared from pools of four buffy coats. RBCs were assessed on Days 1, 21, and 42 for cellular variables and hemolysis. PLTs were assessed on Days 1, 3, and 7 for morphology, CD62P expression, glucose, lactate, and pH. A total of 308 closures were excised after processing and the apertures were measured using digital image analysis. RESULTS The use of the CompoFlow device significantly improved the mean extraction time with 0.46 ± 0.11 sec/mL for the CompoFlow units and 0.52 ± 0.13 sec/mL for the control units. The CompoFlow closures showed a highly reproducible aperture after opening (coefficient of variation, 15%) and the device always remained opened. PLT and RBC products showed acceptable storage variables with no differences between CompoFlow and control. CONCLUSIONS The CompoFlow closure devices improved the level of process control and processing time of blood component production with no negative effects on product quality. PMID:20529007
Jeong, Young-Hoon; Yun, Tae-Jin; Song, Jong-Min; Park, Jung-Jun; Seo, Dong-Man; Koh, Jae-Kon; Lee, Se-Whan; Kim, Mi-Jeong; Kang, Duk-Hyun; Song, Jae-Kwan
2007-09-01
Left ventricular (LV) remodeling and predictors of LV systolic function late after closure of patent ductus arteriosus (PDA) in adults remain to be clearly demonstrated. In 45 patients with PDA, including 28 patients who received successful occlusion using the Amplatzer device (AD group) (AGA, Golden Valley, MN) and 17 patients who received surgical closure (OP group), echocardiography studies were performed before closure and 1 day (AD group) or within 7 days (OP group) after closure, and then were repeated at > or = 6 months (17 +/- 13 months). In both groups, LV ejection fraction (EF) and end-diastolic volume index were significantly decreased immediately after closure, whereas end-systolic volume index did not change. During the long-term follow-up period, end-systolic as well as end-diastolic volume indices decreased significantly in both groups and LV EF recovered compared to the immediate postclosure state. However, LV EF remained low compared to the preclosure state. Five patients (11.1%) including 3 patients in the AD group and 2 patients in the OP group showed persistent late LV systolic dysfunction (EF <50%). In stepwise, multiple logistic regression analysis, preclosure EF was the only independent predictor of late normal postclosure EF (odds ratio, 1.230; 95% CI, 1.054-1.434; P = .008). Receiver operating characteristic curve analysis showed that preclosure EF > or = 62% had a sensitivity of 72% and a specificity of 83% for predicting late normal LV EF after closure. Left ventricular EF remains low late after PDA closure compared with preclosure state in adults. Preclosure LV EF is the best index to predict late postclosure LV EF.
Suitability of Exoseal Vascular Closure Device for Antegrade Femoral Artery Puncture Site Closure
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schmelter, Christopher, E-mail: christopher.schmelter@klinikum-ingolstadt.de; Liebl, Andrea; Poullos, Nektarios
Purpose. To assess the efficacy and safety of the Exoseal vascular closure device for antegrade puncture of the femoral artery. Methods. In a prospective study from February 2011 to January 2012, a total of 93 consecutive patients received a total of 100 interventional procedures via an antegrade puncture of the femoral artery. An Exoseal vascular closure device (6F) was used for closure in all cases. Puncture technique, duration of manual compression, and use of compression bandages were documented. All patients were monitored by vascular ultrasound and color-coded duplex sonography of their respective femoral artery puncture site within 12 to 36more » h after angiography to check for vascular complications. Results. In 100 antegrade interventional procedures, the Exoseal vascular closure device was applied successfully for closure of the femoral artery puncture site in 96 cases (96 of 100, 96.0 %). The vascular closure device could not be deployed in one case as a result of kinking of the vascular sheath introducer and in three cases because the bioabsorbable plug was not properly delivered to the extravascular space adjacent to the arterial puncture site, but instead fully removed with the delivery system (4.0 %). Twelve to 36 h after the procedure, vascular ultrasound revealed no complications at the femoral artery puncture site in 93 cases (93.0 %). Minor vascular complications were found in seven cases (7.0 %), with four cases (4.0 %) of pseudoaneurysm and three cases (3.0 %) of significant late bleeding, none of which required surgery. Conclusion. The Exoseal vascular closure device was safely used for antegrade puncture of the femoral artery, with a high rate of procedural success (96.0 %), a low rate of minor vascular complications (7.0 %), and no major adverse events.« less
Impact of High Seas Closure on Food Security in Low Income Fish Dependent Countries.
Teh, Louise S L; Lam, Vicky W Y; Cheung, William W L; Miller, Dana; Teh, Lydia C L; Sumaila, U Rashid
2016-01-01
We investigate how high seas closure will affect the availability of commonly consumed food fish in 46 fish reliant, and/or low income countries. Domestic consumption of straddling fish species (fish that would be affected by high seas closure) occurred in 54% of the assessed countries. The majority (70%) of countries were projected to experience net catch gains following high seas closure. However, countries with projected catch gains and that also consumed the straddling fish species domestically made up only 37% of the assessed countries. In contrast, much fewer countries (25%) were projected to incur net losses from high seas closure, and of these, straddling species were used domestically in less than half (45%) of the countries. Our findings suggest that, given the current consumption patterns of straddling species, high seas closure may only directly benefit the supply of domestically consumed food fish in a small number of fish reliant and/or low income countries. In particular, it may not have a substantial impact on improving domestic fish supply in countries with the greatest need for improved access to affordable fish, as only one third of this group used straddling fish species domestically. Also, food security in countries with projected net catch gains but where straddling fish species are not consumed domestically may still benefit indirectly via economic activities arising from the increased availability of non-domestically consumed straddling fish species following high seas closure. Consequently, this study suggests that high seas closure can potentially improve marine resource sustainability as well as contribute to human well-being in some of the poorest and most fish dependent countries worldwide. However, caution is required because high seas closure may also negatively affect fish availability in countries that are already impoverished and fish insecure.
Yang, Chuan-Zhong; Lee, Jiun
2008-05-01
The incidence of patent ductus arteriosus (PDA) is high in extremely low birth weight (ELBW) infants. Indomethacin has been widely used in the prophylaxis and treatment of hemodynamically significant PDA. This retrospective study was undertaken to identify factors such as birth weight, gestational age, gender, fetal growth retardation, ductal size, timing of the first dose of indomethacin and side effects of indomethacin, which may affect the successful closure of the PDA with indomethacin in ELBW infants. A cohort of 139 ELBW infants who had received indomethacin treatment for PDA during a consecutive period of more than three years (September 2000 to December 2003) was retrospectively analyzed. Administration of indomethacin was associated with closure of PDA in 108 (77.7%) of 139 ELBW infants, and only 19.4% of infants required surgical ligation of the ductus eventually. There was no significant relationship between closure of PDA with gestational age, gender, fetal growth retardation, and ductal size. A higher birth weight and early use of indomethacin after birth could significantly increase the closure rate of PDA (P<0.05). Side effects of indomethacin such as transient oliguria and hyponatremia during indomethacin therapy did not affect PDA closure. Indomethacin is effective for the treatment of PDA in ELBW infants. A higher rate of ductal closure is related to the increase of birth weight. PDA closure with indomethacin is age-related, and early administration of indomethacin could increase PDA closure and reduce the incidence of hyponatremia. There is no significant difference in major morbidities such as bronchopulmonary dysplasia (BPD), intraventricular hemorrhage (IVH), necrotizing enterocolitis (NEC), and retinopathy of prematurity (ROP) after early treatment. Early screening for hemodynamically significant PDA in ELBW infants and early treatment with indomethacin are recommended.
Large eddy simulation model for wind-driven sea circulation in coastal areas
NASA Astrophysics Data System (ADS)
Petronio, A.; Roman, F.; Nasello, C.; Armenio, V.
2013-12-01
In the present paper a state-of-the-art large eddy simulation model (LES-COAST), suited for the analysis of water circulation and mixing in closed or semi-closed areas, is presented and applied to the study of the hydrodynamic characteristics of the Muggia bay, the industrial harbor of the city of Trieste, Italy. The model solves the non-hydrostatic, unsteady Navier-Stokes equations, under the Boussinesq approximation for temperature and salinity buoyancy effects, using a novel, two-eddy viscosity Smagorinsky model for the closure of the subgrid-scale momentum fluxes. The model employs: a simple and effective technique to take into account wind-stress inhomogeneity related to the blocking effect of emerged structures, which, in turn, can drive local-scale, short-term pollutant dispersion; a new nesting procedure to reconstruct instantaneous, turbulent velocity components, temperature and salinity at the open boundaries of the domain using data coming from large-scale circulation models (LCM). Validation tests have shown that the model reproduces field measurement satisfactorily. The analysis of water circulation and mixing in the Muggia bay has been carried out under three typical breeze conditions. Water circulation has been shown to behave as in typical semi-closed basins, with an upper layer moving along the wind direction (apart from the anti-cyclonic veering associated with the Coriolis force) and a bottom layer, thicker and slower than the upper one, moving along the opposite direction. The study has shown that water vertical mixing in the bay is inhibited by a large level of stable stratification, mainly associated with vertical variation in salinity and, to a minor extent, with temperature variation along the water column. More intense mixing, quantified by sub-critical values of the gradient Richardson number, is present in near-coastal regions where upwelling/downwelling phenomena occur. The analysis of instantaneous fields has detected the presence of large cross-sectional eddies spanning the whole water column and contributing to vertical mixing, associated with the presence of sub-surface horizontal turbulent structures. Analysis of water renewal within the bay shows that, under the typical breeze regimes considered in the study, the residence time of water in the bay is of the order of a few days. Finally, vertical eddy viscosity has been calculated and shown to vary by a couple of orders of magnitude along the water column, with larger values near the bottom surface where density stratification is smaller.
Pilskaln, C H; Anderson, D M; McGillicuddy, D J; Keafer, B A; Hayashi, K; Norton, K
2014-05-01
Quantification of Alexandrium cyst fluxes through the Gulf of Maine water column is central to understanding the linkage between the source and fate of annual Alexandrium blooms in the offshore waters. These blooms often lead to paralytic shellfish poisoning (PSP) and extensive closures of shellfish beds. We report here on time-series sediment trap deployments completed at four offshore locations in the gulf between 2005 and 2010 as components of two ECOHAB-GOM field programs. Data presented documents the substantial spatial and temporal fluctuations in Alexandrium fundyense cyst fluxes in the gulf. Cyst delivery out of the euphotic zone peaked primarily between July and August following annual spring-summer Alexandrium blooms and was greatest in the western gulf. At all sites, cyst flux maxima to the subsurface waters were rarely coincident with seasonal peaks in the total mass export of particulate material indicating that cyst delivery was primarily via individually sinking cysts. Where persistent benthic nepheloid layers (BNLs) exist, significant sediment resuspension input of cysts to the near-bottom water column was evidenced by deep cyst fluxes that were up to several orders of magnitude greater than that measured above the BNL. The largest cyst fluxes in the BNL were observed in the eastern gulf, suggesting greater resuspension energy and BNL cyst inventories in this region. Temporal similarities between peak cyst export out of the upper ocean and peak cyst fluxes in the BNL were observed and document the contribution of seasonal, newly formed cysts to the BNL. The data however also suggest that many Alexandrium cells comprising the massive, short-lived blooms do not transition into cysts. Time-series flow measurements and a simple 1D model demonstrate that the BNL cyst fluxes reflect the combined effects of tidal energy-maintained resuspension, deposition, and input of cysts from the overlying water column.
Pilskaln, C.H.; Anderson, D.M.; McGillicuddy, D.J.; Keafer, B.A.; Hayashi, K.; Norton, K.
2014-01-01
Quantification of Alexandrium cyst fluxes through the Gulf of Maine water column is central to understanding the linkage between the source and fate of annual Alexandrium blooms in the offshore waters. These blooms often lead to paralytic shellfish poisoning (PSP) and extensive closures of shellfish beds. We report here on time-series sediment trap deployments completed at four offshore locations in the gulf between 2005 and 2010 as components of two ECOHAB–GOM field programs. Data presented documents the substantial spatial and temporal fluctuations in Alexandrium fundyense cyst fluxes in the gulf. Cyst delivery out of the euphotic zone peaked primarily between July and August following annual spring–summer Alexandrium blooms and was greatest in the western gulf. At all sites, cyst flux maxima to the subsurface waters were rarely coincident with seasonal peaks in the total mass export of particulate material indicating that cyst delivery was primarily via individually sinking cysts. Where persistent benthic nepheloid layers (BNLs) exist, significant sediment resuspension input of cysts to the near-bottom water column was evidenced by deep cyst fluxes that were up to several orders of magnitude greater than that measured above the BNL. The largest cyst fluxes in the BNL were observed in the eastern gulf, suggesting greater resuspension energy and BNL cyst inventories in this region. Temporal similarities between peak cyst export out of the upper ocean and peak cyst fluxes in the BNL were observed and document the contribution of seasonal, newly formed cysts to the BNL. The data however also suggest that many Alexandrium cells comprising the massive, short-lived blooms do not transition into cysts. Time-series flow measurements and a simple 1D model demonstrate that the BNL cyst fluxes reflect the combined effects of tidal energy-maintained resuspension, deposition, and input of cysts from the overlying water column. PMID:25431527
The semi-diurnal cycle of dissipation in a ROFI: model-measurement comparisons
NASA Astrophysics Data System (ADS)
Simpson, John H.; Burchard, Hans; Fisher, Neil R.; Rippeth, Tom P.
2002-07-01
The Liverpool Bay Region of Freshwater Influence in the Irish Sea exhibits strong horizontal gradients which interact with the dominant tidal flow. A 25 h series of measurements of the cycle of turbulent dissipation with the FLY dissipation profiler shows a strong asymmetry between ebb and flood which is associated with a cycle of increasing stratification on the ebb and progressive mixing on the flood which results in vertical homogeneity as high water is approached. At this time strong dissipation extends throughout the water column in contrast to the ebb when there is a near shutdown of dissipation in the upper half of the column. The cycle of stratification and dissipation is closely consistent for the two semi-diurnal tidal cycles observed. We have attempted to simulate this situation, which involves a complex suite of processes including tidal straining and mixing, using a version of the k-ɛ closure scheme in a 1-d dynamical model which is forced by a combination of the observed tidal flow and horizontal temperature and salinity gradients. The latter were measured directly at the end of the observational series but, in order to focus on the cycle of dissipation, the correct reproduction of the temperature and salinity cycle can be assured by a nudging procedure which obliges the model temperature and salinity values to track the observations. With or without this procedure, the model gives a reasonable account of the dissipation and its asymmetric behaviour on ebb and flood although nudging improves the timing of peak dissipation in the upper part of the water column near highwater. The model has also been used to examine the ratio of shear production (P/ɛ) and buoyancy inputs to dissipation (B/ɛ). The variation of these quantities over the tidal cycle confirms the important role of convective motions forced by tidal straining near the end of the flood phase of the tide.
Device-less patent foramen ovale closure by radiofrequency thermal energy.
Walpoth, Nazan B; Habermacher, Kathrin; Moarof, Igal; Watson, Sandy; Wahl, Andreas; Windecker, Stephan; Schönenberger, Christa; Meier, Bernhard
2008-02-23
The goal of this study was to assess the feasibility, safety and success of a system which uses radiofrequency energy (RFE) rather than a device for percutaneous closure of patent foramen ovale (PFO). Sixteen patients (10 men, 6 women, mean age 50 years) were included in the study. All of them had a proven PFO with documented right-to-left shunt (RLS) after Valsalva manoeuvre (VM) during transoesophageal echocardiography (TEE). The patients had an average PFO diameter of 6 +/- 2 mm at TEE and an average of 23 +/- 4 microembolic signals (MES) in power M-mode transcranial Doppler sonography (pm-TCD), measured over the middle cerebral artery. An atrial septal aneurysm (ASA) was present in 7 patients (44%). Balloon measurement, performed in all patients, revealed a stretched PFO diameter of 8 +/- 3 mm. In 2 patients (stretched diameter 11 and 14 mm respectively, both with ASA >10 mm), radiofrequency was not applied (PFO too large) and the PFO was closed with an Amplatzer PFO occluder instead. A 6-month follow-up TEE was performed in all patients. There were no serious adverse events during the procedure or at follow-up (12 months average). TEE 6 months after the first RFE procedure showed complete closure of the PFO in 50% of the patients (7/14). Closure appeared to be influenced by PFO diameter, complete closure being achieved in 89% (7/8) with a balloon-stretched diameter < or =7 mm but in none of the patients >7 mm. Only one of the complete closure patients had an ASA. Of the remainder, 4 (29%) had an ASA. Although the PFO was not completely closed in this group, some reduction in the diameter of the PFO and in MES was documented by TEE and pm-TCD with VM. Five of the 7 residual shunt patients received an Amplatzer PFO occluder. Except for one patient with a minimal residual shunt, all showed complete closure of PFO at 6-month follow-up TEE and pm-TCD with VM. The other two refused a closure device. The results confirm that radiofrequency closure of the PFO is safe albeit less efficacious and more complex than device closure. The technique in its current state should not be attempted in patients with a balloon-stretched PFO diameter >7 mm and an ASA.
Patent Ductus Arteriosus closure in preterms less than 2kg: Surgery versus transcatheter.
Pamukcu, Ozge; Tuncay, Aydin; Narin, Nazmi; Baykan, Ali; Korkmaz, Levent; Argun, Mustafa; Ozyurt, Abdullah; Sunkak, Suleyman; Uzum, Kazim
2018-01-01
As new devices come into the market, percutaneous techniques improve and interventionalists become more experienced; percutaneous closure gets more common in preterms. In this study we aimed to compare efficacy and safety of Patent Ductus Arteriosus closure surgically versus transcatheter method in preterms <2kg. Best of our knowledge this study is the first one that compares outcomes of surgery and percutaneous Patent Ductus Arteriosus closure in preterms. Between the dates July 1997 to October 2014 in our center Patent Ductus Arteriosus of 26 patients <2kg were closed percutaneously (Group A) and 31 less than 2kg operated (Group B). Weight of patients in percutaneous Patent Ductus Arteriosus closure group was significantly more than the surgery group. Mean gestational age of the patients in Group A was 30±1.8weeks, in group B was 28.6±3.5weeks. In group A; all cases were closed successfully except 4 cases: device embolization in 2, cardiac tamponade and iatrogenic aortic coarctation were seen. Pneumomediastinum and chylothorax were the major complications of the surgery group. There was no statistically significance between complication and success rates between two groups. Percutaneous Patent Ductus Arteriosus closure is the candidate for taking the place of surgery in preterms. However, it is not applied routinely; can only be done in fully equipped large centers by experienced interventionalists. Copyright © 2017 Elsevier B.V. All rights reserved.
Saaby, Marie-Louise
2014-02-01
Stress urinary incontinence (SUI) occurs when the bladder pressure exceeds the urethral pressure in connection with physical effort or exertion or when sneezing or coughing and depends both on the strength of the urethral closure function and the abdominal pressure to which it is subjected. The urethral closure function in continent women and the dysfunction causing SUI are not known in details. The currently accepted view is based on the concept of a sphincteric unit and a support system. Our incomplete knowledge relates to the complexity of the closure apparatus and to inadequate assessment methods which so far have not provided robust urodynamic diagnostic tools, severity measures, or parameters to assess outcome after intervention. Urethral Pressure Reflectometry (UPR) is a novel method that measures the urethral pressure and cross-sectional area (by use of sound waves) simultaneously. The technique involves insertion of only a small, light and flexible polyurethane bag in the urethra and therefore avoids the common artifacts encountered with conventional methods. The UPR parameters can be obtained at a specific site of the urethra, e.g. the high pressure zone, and during various circumstances, i.e. resting and squeezing. During the study period, we advanced the UPR technique to enable faster measurement (within 7 seconds by the continuous technique) which allowed assessment during increased intra-abdominal pressure induced by physical straining. We investigated the urethral closure function in continent and SUI women during resting and straining by the "fast" UPR technique. Thereby new promising urethral parameters were provided that allowed characterization of the closure function based on the permanent closure forces (primarily generated by the sphincteric unit, measured by the Po-rest) and the adjunctive closure forces (primarily generated by the support system, measured by the abdominal to urethral pressure impact ratio (APIR)). The new parameters enabled a more detailed description of the efficiency of the closure function and the extent and nature of a possible dysfunction in the individual woman. The urethral closure equation (UCE) and urethral opening pressure at an abdominal pressure of 50 cm H2O (Po-Abd 50), respectively, which combine the permanent and the adjunctive closure forces, could separate continent and SUI women and thus appear to be excellent diagnostic tests. Moreover, the parameters showed highly significant negative correlation with ICIQ-SF, pad test and the number of incontinence episodes per week and are therefore valid as urodynamic severity measures. UPR in SUI women before and after TVT demonstrated a more efficient urethral closure function after the operation. The Po-rest was unchanged suggesting that the sphincteric unit was virtually unaltered and hence the permanent closure forces unchanged. However, the resting opening elastance increased by 18% indicating that at the resting state the TVT somewhat improves the closure function by providing increased resistance against the dilation of the urethra, which probably explains the decreased maximum urine flow rate found after TVT in this and previous studies. The APIR increased in all patients after TVT suggesting that the support system was re-established and thus the adjunctive closure forces improved, regardless of the type of pre-operative dysfunction. The new UPR parameters may be used as outcome measures after treatment.
Uncertainty Quantification of Multi-Phase Closures
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nadiga, Balasubramanya T.; Baglietto, Emilio
In the ensemble-averaged dispersed phase formulation used for CFD of multiphase ows in nuclear reactor thermohydraulics, closures of interphase transfer of mass, momentum, and energy constitute, by far, the biggest source of error and uncertainty. Reliable estimators of this source of error and uncertainty are currently non-existent. Here, we report on how modern Validation and Uncertainty Quanti cation (VUQ) techniques can be leveraged to not only quantify such errors and uncertainties, but also to uncover (unintended) interactions between closures of di erent phenomena. As such this approach serves as a valuable aide in the research and development of multiphase closures.more » The joint modeling of lift, drag, wall lubrication, and turbulent dispersion|forces that lead to tranfer of momentum between the liquid and gas phases|is examined in the frame- work of validation of the adiabatic but turbulent experiments of Liu and Banko , 1993. An extensive calibration study is undertaken with a popular combination of closure relations and the popular k-ϵ turbulence model in a Bayesian framework. When a wide range of super cial liquid and gas velocities and void fractions is considered, it is found that this set of closures can be validated against the experimental data only by allowing large variations in the coe cients associated with the closures. We argue that such an extent of variation is a measure of uncertainty induced by the chosen set of closures. We also nd that while mean uid velocity and void fraction pro les are properly t, uctuating uid velocity may or may not be properly t. This aspect needs to be investigated further. The popular set of closures considered contains ad-hoc components and are undesirable from a predictive modeling point of view. Consequently, we next consider improvements that are being developed by the MIT group under CASL and which remove the ad-hoc elements. We use non-intrusive methodologies for sensitivity analysis and calibration (using Dakota) to study sensitivities of the CFD representation (STARCCM+) of uid velocity pro les and void fraction pro les in the context of Shaver and Podowski, 2015 correction to lift, and the Lubchenko et al., 2017 formulation of wall lubrication.« less
Evaluation of the Momentum Closure Schemes in MPAS-Ocean
NASA Astrophysics Data System (ADS)
Zhao, Shimei; Liu, Yudi; Liu, Wei
2018-04-01
In order to compare and evaluate the performances of the Laplacian viscosity closure, the biharmonic viscosity closure, and the Leith closure momentum schemes in the MPAS-Ocean model, a variety of physical quantities, such as the relative reference potential energy (RPE) change, the RPE time change rate (RPETCR), the grid Reynolds number, the root mean square (RMS) of kinetic energy, and the spectra of kinetic energy and enstrophy, are calculated on the basis of results of a 3D baroclinic periodic channel. Results indicate that: 1) The RPETCR demonstrates a saturation phenomenon in baroclinic eddy tests. The critical grid Reynolds number corresponding to RPETCR saturation differs between the three closures: the largest value is in the biharmonic viscosity closure, followed by that in the Laplacian viscosity closure, and that in the Leith closure is the smallest. 2) All three closures can effectively suppress spurious dianeutral mixing by reducing the grid Reynolds number under sub-saturation conditions of the RPETCR, but they can also damage certain physical processes. Generally, the damage to the rotation process is greater than that to the advection process. 3) The dissipation in the biharmonic viscosity closure is strongly dependent on scales. Most dissipation concentrates on small scales, and the energy of small-scale eddies is often transferred to large-scale kinetic energy. The viscous dissipation in the Laplacian viscosity closure is the strongest on various scales, followed by that in the Leith closure. Note that part of the small-scale kinetic energy is also transferred to large-scale kinetic energy in the Leith closure. 4) The characteristic length scale L and the dimensionless parameter D in the Leith closure are inherently coupled. The RPETCR is inversely proportional to the product of D and L. When the product of D and L is constant, both the simulated RPETCR and the inhibition of spurious dianeutral mixing are the same in all tests using the Leith closure. The dissipative scale in the Leith closure depends on the parameter L, and the dissipative intensity depends on the parameter D. 5) Although optimal results may not be achieved by using the optimal parameters obtained from the 2D barotropic model in the 3D baroclinic simulation, the total energies are dissipative in all three closures. Dissipation is the strongest in the biharmonic viscosity closure, followed by that in the Leith closure, and that in the Laplacian viscosity closure is the weakest. Mesoscale eddies develop the fastest in the biharmonic viscosity closure after the baroclinic adjustment process finishes, and the kinetic energy reaches its maximum, which is attributed to the smallest dissipation of enstrophy in the biharmonic viscosity closure. Mesoscale eddies develop the slowest, and the kinetic energy peak value is the smallest in the Laplacian viscosity closure. Results in the Leith closure are between that in the biharmonic viscosity closure and the Laplacian viscosity closure.
Closure of fatigue cracks at high strains
NASA Technical Reports Server (NTRS)
Iyyer, N. S.; Dowling, N. E.
1985-01-01
Experiments were conducted on smooth specimens to study the closure behavior of short cracks at high cyclic strains under completely reversed cycling. Testing procedures and methodology, and closure measurement techniques, are described in detail. The strain levels chosen for the study cover from predominantly elastic to grossly plastic strains. Crack closure measurements are made at different crack lengths. The study reveals that, at high strains, cracks close only as the lowest stress level in the cycle is approached. The crack opening is observed to occur in the compressive part of the loading cycle. The applied stress needed to open a short crack under high strain is found to be less than for cracks under small scale yielding. For increased plastic deformations, the value of sigma sub op/sigma sub max is observed to decrease and approaches the value of R. Comparison of the experimental results with existing analysis is made and indicates the limitations of the small scale yielding approach where gross plastic deformation behavior occurs.
Murakami, Yohko; Wang, Dandan; Burkemper, Bruce; Lin, Shan C; Varma, Rohit
2016-08-01
To compare grading of goniophotographic images and gonioscopy in assessing the iridocorneal angle. In a population-based, cross-sectional study, participants underwent gonioscopy and goniophotographic imaging during the same visit. The iridocorneal angle was classified as closed if the posterior trabecular meshwork could not be seen. A single masked observer graded the goniophotographic images, and each eye was classified as having angle closure based on the number of closed quadrants. Agreement between the methods was analyzed by calculating kappa (κ) and first-order agreement coefficient (AC1) statistics and comparison of area under receiver operating characteristic curves (AUC). A total of 4149 Chinese Americans (3994 eyes) were included in this study. The agreement for angle closure diagnosis between gonioscopy and EyeCam was moderate to excellent (κ = 0.60, AC1 0.90, AUC 0.76-0.80). Detection of iridocorneal angle closure based on goniophotographic imaging shows moderate to very good agreement with angle closure assessment using gonioscopy.
40 CFR 264.151 - Wording of the instruments.
Code of Federal Regulations, 2013 CFR
2013-07-01
... assurance for closure or post-closure care is demonstrated through the financial test specified in subpart H... parts 264 and 265. The current closure and/or post-closure cost estimates covered by such a test are... CFR parts 264 and 265. The current closure and/or post-closure cost estimate covered by the test are...
40 CFR 264.151 - Wording of the instruments.
Code of Federal Regulations, 2012 CFR
2012-07-01
... assurance for closure or post-closure care is demonstrated through the financial test specified in subpart H... parts 264 and 265. The current closure and/or post-closure cost estimates covered by such a test are... CFR parts 264 and 265. The current closure and/or post-closure cost estimate covered by the test are...
40 CFR 264.151 - Wording of the instruments.
Code of Federal Regulations, 2010 CFR
2010-07-01
... assurance for closure or post-closure care is demonstrated through the financial test specified in subpart H... parts 264 and 265. The current closure and/or post-closure cost estimates covered by such a test are... CFR parts 264 and 265. The current closure and/or post-closure cost estimate covered by the test are...
40 CFR 264.118 - Post-closure plan; amendment of plan.
Code of Federal Regulations, 2014 CFR
2014-07-01
... days after an unexpected event has occurred which has affected the post-closure plan. An owner or... 40 Protection of Environment 26 2014-07-01 2014-07-01 false Post-closure plan; amendment of plan... FACILITIES Closure and Post-Closure § 264.118 Post-closure plan; amendment of plan. (a) Written Plan. The...
40 CFR 264.118 - Post-closure plan; amendment of plan.
Code of Federal Regulations, 2011 CFR
2011-07-01
... days after an unexpected event has occurred which has affected the post-closure plan. An owner or... 40 Protection of Environment 26 2011-07-01 2011-07-01 false Post-closure plan; amendment of plan... FACILITIES Closure and Post-Closure § 264.118 Post-closure plan; amendment of plan. (a) Written Plan. The...
40 CFR 264.118 - Post-closure plan; amendment of plan.
Code of Federal Regulations, 2012 CFR
2012-07-01
... days after an unexpected event has occurred which has affected the post-closure plan. An owner or... 40 Protection of Environment 27 2012-07-01 2012-07-01 false Post-closure plan; amendment of plan... FACILITIES Closure and Post-Closure § 264.118 Post-closure plan; amendment of plan. (a) Written Plan. The...
40 CFR 264.118 - Post-closure plan; amendment of plan.
Code of Federal Regulations, 2013 CFR
2013-07-01
... days after an unexpected event has occurred which has affected the post-closure plan. An owner or... 40 Protection of Environment 27 2013-07-01 2013-07-01 false Post-closure plan; amendment of plan... FACILITIES Closure and Post-Closure § 264.118 Post-closure plan; amendment of plan. (a) Written Plan. The...
40 CFR 264.118 - Post-closure plan; amendment of plan.
Code of Federal Regulations, 2010 CFR
2010-07-01
... days after an unexpected event has occurred which has affected the post-closure plan. An owner or... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Post-closure plan; amendment of plan... FACILITIES Closure and Post-Closure § 264.118 Post-closure plan; amendment of plan. (a) Written Plan. The...
NASA Astrophysics Data System (ADS)
Vogler, D.; Settgast, R. R.; Annavarapu, C.; Madonna, C.; Bayer, P.; Amann, F.
2018-02-01
In this work, we present the application of a fully coupled hydro-mechanical method to investigate the effect of fracture heterogeneity on fluid flow through fractures at the laboratory scale. Experimental and numerical studies of fracture closure behavior in the presence of heterogeneous mechanical and hydraulic properties are presented. We compare the results of two sets of laboratory experiments on granodiorite specimens against numerical simulations in order to investigate the mechanical fracture closure and the hydro-mechanical effects, respectively. The model captures fracture closure behavior and predicts a nonlinear increase in fluid injection pressure with loading. Results from this study indicate that the heterogeneous aperture distributions measured for experiment specimens can be used as model input for a local cubic law model in a heterogeneous fracture to capture fracture closure behavior and corresponding fluid pressure response.
Yoon, Seung-Yil; Sagi, Hemi; Goldhammer, Craig; Li, Lei
2012-01-01
Container closure integrity (CCI) is a critical factor to ensure that product sterility is maintained over its entire shelf life. Assuring the CCI during container closure (C/C) system qualification, routine manufacturing and stability is important. FDA guidance also encourages industry to develop a CCI physical testing method in lieu of sterility testing in a stability program. A mass extraction system has been developed to check CCI for a variety of container closure systems such as vials, syringes, and cartridges. Various types of defects (e.g., glass micropipette, laser drill, wire) were created and used to demonstrate a detection limit. Leakage, detected as mass flow in this study, changes as a function of defect length and diameter. Therefore, the morphology of defects has been examined in detail with fluid theories. This study demonstrated that a mass extraction system was able to distinguish between intact samples and samples with 2 μm defects reliably when the defect was exposed to air, water, placebo, or drug product (3 mg/mL concentration) solution. Also, it has been verified that the method was robust, and capable of determining the acceptance limit using 3σ for syringes and 6σ for vials. Sterile products must maintain their sterility over their entire shelf life. Container closure systems such as those found in syringes and vials provide a seal between rubber and glass containers. This seal must be ensured to maintain product sterility. A mass extraction system has been developed to check container closure integrity for a variety of container closure systems such as vials, syringes, and cartridges. In order to demonstrate the method's capability, various types of defects (e.g., glass micropipette, laser drill, wire) were created in syringes and vials and were tested. This study demonstrated that a mass extraction system was able to distinguish between intact samples and samples with 2 μm defects reliably when the defect was exposed to air, water, placebo, or drug product (3 mg/mL concentration) solution. Also, it was verified that the method showed consistent results, and was able to determine the acceptance limit using 3σ for syringes and 6σ for vials.
Henson, John H.; Nazarian, Ronniel; Schulberg, Katrina L.; Trabosh, Valerie A.; Kolnik, Sarah E.; Burns, Andrew R.; McPartland, Kenneth J.
2002-01-01
The actomyosin purse string is an evolutionarily conserved contractile structure that is involved in cytokinesis, morphogenesis, and wound healing. Recent studies suggested that an actomyosin purse string is crucial for the closure of wounds in single cells. In the present study, morphological and pharmacological methods were used to investigate the role of this structure in the closure of wounds in the peripheral cytoplasm of sea urchin coelomocytes. These discoidal shaped cells underwent a dramatic form of actin-based centripetal/retrograde flow and occasionally opened and closed spontaneous wounds in their lamellipodia. Fluorescent phalloidin staining indicated that a well defined fringe of actin filaments assembles from the margin of these holes, and drug studies with cytochalasin D and latrunculin A indicated that actin polymerization is required for wound closure. Additional evidence that actin polymerization is involved in wound closure was provided by the localization of components of the Arp2/3 complex to the wound margin. Significantly, myosin II immunolocalization demonstrated that it is not associated with wound margins despite being present in the perinuclear region. Pharmacological evidence for the lack of myosin II involvement in wound closure comes from experiments in which a microneedle was used to produce wounds in cells in which actomyosin contraction was inhibited by treatment with kinase inhibitors. Wounds produced in kinase inhibitor-treated cells closed in a manner similar to that seen with control cells. Taken together, our results suggest that an actomyosin purse string mechanism is not responsible for the closure of lamellar wounds in coelomocytes. We hypothesize that the wounds heal by means of a combination of the force produced by actin polymerization alone and centripetal flow. Interestingly, these cells did assemble an actomyosin structure around the margin of phagosome-like membrane invaginations, indicating that myosin is not simply excluded from the periphery by some general mechanism. The results indicate that the actomyosin purse string is not the only mechanism that can mediate wound closure in single cells. PMID:11907278
Henson, John H; Nazarian, Ronniel; Schulberg, Katrina L; Trabosh, Valerie A; Kolnik, Sarah E; Burns, Andrew R; McPartland, Kenneth J
2002-03-01
The actomyosin purse string is an evolutionarily conserved contractile structure that is involved in cytokinesis, morphogenesis, and wound healing. Recent studies suggested that an actomyosin purse string is crucial for the closure of wounds in single cells. In the present study, morphological and pharmacological methods were used to investigate the role of this structure in the closure of wounds in the peripheral cytoplasm of sea urchin coelomocytes. These discoidal shaped cells underwent a dramatic form of actin-based centripetal/retrograde flow and occasionally opened and closed spontaneous wounds in their lamellipodia. Fluorescent phalloidin staining indicated that a well defined fringe of actin filaments assembles from the margin of these holes, and drug studies with cytochalasin D and latrunculin A indicated that actin polymerization is required for wound closure. Additional evidence that actin polymerization is involved in wound closure was provided by the localization of components of the Arp2/3 complex to the wound margin. Significantly, myosin II immunolocalization demonstrated that it is not associated with wound margins despite being present in the perinuclear region. Pharmacological evidence for the lack of myosin II involvement in wound closure comes from experiments in which a microneedle was used to produce wounds in cells in which actomyosin contraction was inhibited by treatment with kinase inhibitors. Wounds produced in kinase inhibitor-treated cells closed in a manner similar to that seen with control cells. Taken together, our results suggest that an actomyosin purse string mechanism is not responsible for the closure of lamellar wounds in coelomocytes. We hypothesize that the wounds heal by means of a combination of the force produced by actin polymerization alone and centripetal flow. Interestingly, these cells did assemble an actomyosin structure around the margin of phagosome-like membrane invaginations, indicating that myosin is not simply excluded from the periphery by some general mechanism. The results indicate that the actomyosin purse string is not the only mechanism that can mediate wound closure in single cells.
Closure of oroantral communications using biodegradable polyurethane foam: a feasibility study.
Visscher, Susan H; van Minnen, Baucke; Bos, Rudolf R M
2010-02-01
The aim of this study was to assess the feasibility of biodegradable polyurethane (PU) foam for closure of oroantral communications (OACs). Ten consecutive patients with OACs (existing <24 hours) were treated with PU foam. Standardized evaluations were performed at 2 weeks and 8 weeks after closure of the OAC. In 5 patients, the OACs were closed successfully without complications. Three patients developed sinusitis, which was conservatively managed with antibiotics in 2 cases. In 1 case the sinus was reopened for irrigation, after which a buccal flap procedure was performed. In 2 patients the OAC recurred and was surgically closed with a buccal flap after thorough irrigation. In this feasibility study, closure was achieved in 7 of the 10 patients without further surgical intervention. Complications of the procedure using PU foam may be related to the fit of the foam in the socket and the size of the perforation. In general, closure of OACs with biodegradable polyurethane foam is feasible and has the potential to spare a large number of patients with OACs a surgical procedure. Furthermore, in case the treatment with PU foam fails to close the OAC, the attending physician can always fall back on the standard surgical procedure. Copyright 2010 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.
2013-01-01
Introduction The use of Negative Pressure Wound Therapy (NPWT) for temporary abdominal closure of open abdomen (OA) wounds is widely accepted. Published outcomes vary according to the specific nature and the aetiology that resulted in an OA. The aim of this study was to evaluate the effectiveness of a new NPWT system specifically used OA resulting from abdominal trauma. Methods A prospective study on trauma patients requiring temporary abdominal closure (TAC) with grade 1or 2 OA was carried out. All patients were treated with NPWT (RENASYS AB Smith & Nephew) to achieve TAC. The primary outcome measure was time taken to achieve fascial closure and secondary outcomes were complications and mortality. Results A total of 20 patients were included. Thirteen patients (65%) achieved fascial closure following a median treatment period of 3 days. Four patients (20%) died of causes unrelated to NPWT. Complications included fistula formation in one patient (5%) with spontaneous resolution during NPWT), bowel necrosis in a single patient (5%) and three cases of infection (15%). No fistulae were present at the end of NPWT. Conclusion This new NPWT kit is safe and effective and results in a high rate of fascial closure and low complication rates in the severely injured trauma patient. PMID:23305306
Simple skin-stretching device in assisted tension-free wound closure
Cheng, Li-Fu; Lee, Jiunn-Tat; Hsu, Honda; Wu, Meng-Si
2017-01-01
Background Numerous conventional wound reconstruction methods such as wound undermining with direct suture, skin graft, and flap surgery can be used to treat large wounds. The adequate undermining of the skin flaps of a wound is a commonly used technique for achieving the closure of large tension wounds; however, the use of tension to approximate and suture the skin flaps can cause ischemic marginal necrosis. The purpose of this study is to use elastic rubber bands to relieve the tension of direct wound closure for simultaneously minimizing the risks of wound dehiscence and wound edge ischemia that lead to necrosis. Materials and Methods This retrospective study was conducted to evaluate our clinical experiences with 22 large wounds, which involved performing primary closures under a considerable amount of tension by using elastic rubber bands in a skin-stretching technique following a wide undermining procedure. Assessment of the results entailed complete wound healing and related complications. Results All 22 wounds in our study showed fair to good results except for one. The mean success rate was approximately 95.45%. Conclusion The simple skin-stretching design enabled tension-free skin closure, which pulled the bilateral undermining skin flaps as bilateral fasciocutaneous advancement flaps. The skin-stretching technique was generally successful. PMID:28195891
Ischaemic stroke with patent foramen ovale.
Jusufovic, Mirza; Thomassen, Lars; Skjelland, Mona
2014-01-28
There is no sound scientific documentation of current guidelines for the treatment of cerebral infarction assumed to be due to patent foramen ovale. In this article, we present a young patient with this condition. In addition, we provide a general overview of the prevalence, recommended assessment and indications for treatment of patent foramen ovale in ischaemic stroke patients. The article is based on a non-systematic search in PubMed. We emphasise three recently published randomised trials on the subject. Transoesophageal echocardiography with saline contrast is the gold standard for detecting patent foramen ovale. Just who will benefit from the diagnosis and treatment of this condition remains unclear, however. None of the three randomised studies of antithrombotic treatment versus transcatheter closure in patients who have suffered ischaemic stroke show a difference in outcomes, but subgroup analyses indicate that closure in young patients (age <50 years) with a large foramen ovale reduces the number of recurrent ischaemic events. Two other randomised studies of antithrombotic treatment alone versus closure are presently ongoing. For stroke patients with patent foramen ovale, the choice between lifelong antithrombotic therapy alone and transcatheter closure is a difficult one. Treatment with antiplatelet agents remains the first choice in most cases. Well-designed studies are needed to identify which patients will benefit most from closure.
Fabrication and investigation of electrochromatographic columns with a simplex configuration.
Liu, Qing; Yang, Lijun; Wang, Qiuquan; Zhang, Bo
2014-07-04
Duplex capillary columns with a packed and an open section are widely used in electrochromatography (CEC). The duplex column configuration leads to non-uniform voltage drop, electrical field distribution and separation performance. It also adds to the complexity in understanding and optimizing electrochromatographic process. In this study, we introduced a simplex column configuration based on single particle fritting technology. The new column configuration has an essentially uniform packed bed through the entire column length, with only 1mm length left unpacked serving as the optical detection window. The study shows that a simplex column has higher separation efficiency than a duplex column, especially at the high voltage range, due to the consistent distribution of electrical field over the column length. In comparison to the duplex column, the simplex column presented a lower flow rate at the same applied voltage, suggesting that an open section may support a higher speed than a packed section. In practice, the long and short ends of the simplex column could be used as independent CEC columns respectively. This "two-in-one" bi-functional column configuration provided extra flexibilities in selecting and optimizing electrochromatographic conditions. Copyright © 2014 Elsevier B.V. All rights reserved.
Fracture mechanics analyses of partial crack closure in shell structures
NASA Astrophysics Data System (ADS)
Zhao, Jun
2007-12-01
This thesis presents the theoretical and finite element analyses of crack-face closure behavior in shells and its effect on the stress intensity factor under a bending load condition. Various shell geometries, such as spherical shell, cylindrical shell containing an axial crack, cylindrical shell containing a circumferential crack and shell with double curvatures, are all studied. In addition, the influence of material orthotropy on the crack closure effect in shells is also considered. The theoretical formulation is developed based on the shallow shell theory of Delale and Erdogan, incorporating the effect of crack-face closure at the compressive edges. The line-contact assumption, simulating the crack-face closure at the compressive edges, is employed so that the contact force at the closure edges is introduced, which can be translated to the mid-plane of the shell, accompanied by an additional distributed bending moment. The unknown contact force is computed by solving a mixed-boundary value problem iteratively, that is, along the crack length, either the normal displacement of the crack face at the compressive edges is equal to zero or the contact pressure is equal to zero. It is found that due to the curvature effects crack closure may not always occur on the entire length of the crack, depending on the direction of the bending load and the geometry of the shell. The crack-face closure influences significantly the magnitude of the stress intensity factors; it increases the membrane component but decreases the bending component. The maximum stress intensity factor is reduced by the crack-face closure. The significant influence of geometry and material orthotropy on rack closure behavior in shells is also predicted based on the analytical solutions. Three-dimensional FEA is performed to validate the theoretical solutions. It demonstrates that the crack face closure occurs actually over an area, not on a line, but the theoretical solutions of the stress intensity factor and the FEA solutions are in good agreement, because the contact area is very small compared with the shell thickness.
Hormonal regulation of floret closure of rice (Oryza sativa)
Huang, Youming; Zeng, Xiaochun
2018-01-01
Plant hormones play important roles in regulating every aspect of growth, development, and metabolism of plants. We are interested in understanding hormonal regulation of floret opening and closure in plants. This is a particularly important problem for hybrid rice because regulation of flowering time is vitally important in hybrid rice seed production. However, little was known about the effects of plant hormones on rice flowering. We have shown that jasmonate and methyl jasmonate play significant roles in promoting rice floret opening. In this study, we investigated the effects of auxins including indole-3-acidic acid (IAA), indole-3-butyric acid (IBA), 1-naphthalene-acetic acid (NAA), 2,4-dichlorophenoxy acetic acid (2,4-D) and 3,6-dichloro-2-methoxybenzoic acid (DIC) and abscisic acid (ABA) on floret closure of four fertile and three sterile varieties of rice. The results from field studies in three growing seasons in 2013–2015 showed that the percentages of closed florets were significantly lower in plants treated with IAA, IBA, 2,4-D, DIC and NAA and that the durations of floret opening were significantly longer in plants treated with the same auxins. The auxins exhibited time- and concentration-dependant effects on floret closure. ABA displayed opposite effects of auxins because it increased the percentages of floret closure and decreased the length of floret opening of rice varieties. The degree of auxin-inhibiting and ABA-promoting effects on floret closure was varied somewhat but not significantly different among the rice varieties. Endogenous IAA levels were the highest in florets collected shortly before opening followed by a sharp decline in florets with maximal angles of opening and a significant jump of IAA levels shortly after floret closure in both fertile and sterile rice plants. ABA levels showed an opposite trend in the same samples. Our results showed that auxins delayed but ABA promoted the closure of rice floret regardless of the varieties. PMID:29879200
Sadique, Zia; Lopman, Ben; Cooper, Ben S; Edmunds, W John
2016-02-01
Norovirus is the most common cause of outbreaks of acute gastroenteritis in National Health Service hospitals in the United Kingdom. Wards (units) are often closed to new admissions to stop the spread of the virus, but there is limited evidence describing the cost-effectiveness of ward closure. An economic analysis based on the results from a large, prospective, active-surveillance study of gastroenteritis outbreaks in hospitals and from an epidemic simulation study compared alternative ward closure options evaluated at different time points since first infection, assuming different efficacies of ward closure. A total of 232 gastroenteritis outbreaks occurring in 14 hospitals over a 1-year period were analyzed. The risk of a new outbreak in a hospital is significantly associated with the number of admission, general medical, and long-stay wards that are concurrently affected but is less affected by the level of community transmission. Ward closure leads to higher costs but reduces the number of new outbreaks by 6%-56% and the number of clinical cases by 1%-55%, depending on the efficacy of the intervention. The incremental cost per outbreak averted varies from £10 000 ($14 000) to £306 000 ($428 000), and the cost per case averted varies from £500 ($700) to £61 000 ($85 000). The cost-effectiveness of ward closure decreases as the efficacy of the intervention increases, and the cost-effectiveness increases with the timing of the intervention. The efficacy of ward closure is critical from a cost-effectiveness perspective. Ward closure may be cost-effective, particularly if targeted to high-throughput units. Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.
Tolonen, Matti; Mentula, Panu; Sallinen, Ville; Rasilainen, Suvi; Bäcklund, Minna; Leppäniemi, Ari
2017-06-01
Open abdomen (OA) treatment in patients with peritonitis is increasing worldwide. Various temporary abdominal closure devices are being used. This study included patients with complicated diffuse secondary peritonitis, OA, and vacuum-assisted wound closure and mesh-mediated fascial traction (VAWCM). The aim of this study was to describe mortality and major morbidity in terms of delayed primary fascial closure and enteroatmospheric fistula rates. This was a single-academic-center retrospective study of consecutive patients with diffuse peritonitis, OA, and VAWCM between years 2008 and 2016. Descriptive and univariate analyses were performed. Forty-one patients were identified and analyzed. Median age was 59 years, preoperative septic shock was diagnosed in 54% (n = 22), and 59% (n = 24) had a postoperative peritonitis. Mortality was 29% (n = 12), and 76% (n = 31) of patients were admitted in the intensive care unit. The median duration of OA was 7 days with a median of two dressing changes. Delayed primary fascial closure rate among survivors was 92% (n = 33), and enteroatmospheric fistulas developed in 7% (n = 3). In a subgroup analysis, patients with OA in the primary laparotomy for peritonitis (n = 27) were compared with patients with OA in the subsequent laparotomies (n = 14). There were no significant differences between groups. The VAWCM technique in patients with complicated secondary diffuse peritonitis and OA yields excellent results in terms of delayed primary fascial closure rate and a low number of enteroatmospheric fistulas. It seems to be safe to close the abdomen at the index laparotomy, if possible, even if there is a risk of a need of OA later. Therapeutic/care management study, level IV.
Changela, Kinesh; Culliford, Andrea; Duddempudi, Sushil; Krishnaiah, Mahesh; Anand, Sury
2015-01-01
Objectives: The Over-The-Scope-Clip (OTSC) has had an evolving role in endoscopic closure of gastrointestinal wall defects, in hemostasis of primary or postinterventional bleeding, and approximation of postbariatric surgery defects. Rapid and effective closure of gastrocutaneous (GC) fistulae using this device has been recently described in the literature. The aim of this study was to evaluate the technical feasibility, efficacy and safety of OTSC as an effective tool in the management of persistent GC fistulae secondary to a complication of percutaneous endoscopic gastrostomy (PEG) tube placement. Method: In this multicenter prospective observational study, we describe our experience with OTSC in the closure of persistent GC fistulas secondary to PEG tube placement. Patients with GC fistulas were sequentially enrolled with a mean age of 84 years. Primary treatment outcome was the immediate successful closure of GC fistula and resolution of leak. Secondary outcome was no recurrence of the fistula and leaks on follow up. Results: A total of 10 patients were enrolled over the study period. Mean age was 84.4 ± 8.75 years. The primary treatment outcome was achieved in all the patients undergoing this intervention. Secondary outcome was observed in 9/10 (90%) subjects. No procedural complications were reported. Larger fistulae (>2.5 cm) and those with significant fibrosis were more difficult to close with the OTSC system. The mean follow-up time after OTSC application was 43.7 ± 20.57 days. A limitation of this study was that there was no control group. Conclusions: OTSC application is a safe and effective endoscopic approach for the closure of persistent GC fistulae secondary to a complication of PEG tube placement. PMID:26136836
Singhal, Shashideep; Changela, Kinesh; Culliford, Andrea; Duddempudi, Sushil; Krishnaiah, Mahesh; Anand, Sury
2015-07-01
The Over-The-Scope-Clip (OTSC) has had an evolving role in endoscopic closure of gastrointestinal wall defects, in hemostasis of primary or postinterventional bleeding, and approximation of postbariatric surgery defects. Rapid and effective closure of gastrocutaneous (GC) fistulae using this device has been recently described in the literature. The aim of this study was to evaluate the technical feasibility, efficacy and safety of OTSC as an effective tool in the management of persistent GC fistulae secondary to a complication of percutaneous endoscopic gastrostomy (PEG) tube placement. In this multicenter prospective observational study, we describe our experience with OTSC in the closure of persistent GC fistulas secondary to PEG tube placement. Patients with GC fistulas were sequentially enrolled with a mean age of 84 years. Primary treatment outcome was the immediate successful closure of GC fistula and resolution of leak. Secondary outcome was no recurrence of the fistula and leaks on follow up. A total of 10 patients were enrolled over the study period. Mean age was 84.4 ± 8.75 years. The primary treatment outcome was achieved in all the patients undergoing this intervention. Secondary outcome was observed in 9/10 (90%) subjects. No procedural complications were reported. Larger fistulae (>2.5 cm) and those with significant fibrosis were more difficult to close with the OTSC system. The mean follow-up time after OTSC application was 43.7 ± 20.57 days. A limitation of this study was that there was no control group. OTSC application is a safe and effective endoscopic approach for the closure of persistent GC fistulae secondary to a complication of PEG tube placement.
2016-01-01
Purpose The aim of this study was to evaluate alterations of papilla dimensions after orthodontic closure of the diastema between maxillary central incisors. Methods Sixty patients who had a visible diastema between maxillary central incisors that had been closed by orthodontic approximation were selected for this study. Various papilla dimensions were assessed on clinical photographs and study models before the orthodontic treatment and at the follow-up examination after closure of the diastema. Influences of the variables assessed before orthodontic treatment on the alterations of papilla height (PH) and papilla base thickness (PBT) were evaluated by univariate regression analysis. To analyze potential influences of the 3-dimensional papilla dimensions before orthodontic treatment on the alterations of PH and PBT, a multiple regression model was formulated including the 3-dimensional papilla dimensions as predictor variables. Results On average, PH decreased by 0.80 mm and PBT increased after orthodontic closure of the diastema (P<0.01). Univariate regression analysis revealed that the PH (P=0.002) and PBT (P=0.047) before orthodontic treatment influenced the alteration of PH. With respect to the alteration of PBT, the diastema width (P=0.045) and PBT (P=0.000) were found to be influential factors. PBT before the orthodontic treatment significantly influenced the alteration of PBT in the multiple regression model. Conclusions PH decreased but PBT increased after orthodontic closure of the diastema. The papilla dimensions before orthodontic treatment influenced the alterations of PH and PBT after closure of the diastema. The PBT increased more when the diastema width before the orthodontic treatment was larger. PMID:27382507
Unitarity and the three flavor neutrino mixing matrix
Parke, Stephen; Ross-Lonergan, Mark
2016-06-14
Unitarity is a fundamental property of any theory required to ensure we work in a theoretically consistent framework. In comparison with the quark sector, experimental tests of unitarity for the 3x3 neutrino mixing matrix are considerably weaker. It must be remembered that the vast majority of our information on the neutrino mixing angles originates from v - e and v μ disappearance experiments, with the assumption of unitarity being invoked to constrain the remaining elements. New physics can invalidate this assumption for the 3x3 subset and thus modify our precision measurements. We also perform a reanalysis to see how globalmore » knowledge is altered when one refits oscillation results without assuming unitarity, and present 3σ ranges for allowed U PMNS elements consistent with all observed phenomena. We calculate the bounds on the closure of the six neutrino unitarity triangles, with the closure of the v - e and v μ triangle being constrained to be ≤0.03, while the remaining triangles are significantly less constrained to be ≤ 0.1 - 0.2. Similarly for the row and column normalization, we find their deviation from unity is constrained to be ≤ 0.2 - 0.4, for four out of six such normalizations, while for the v μ and v e row normalization the deviations are constrained to be ≤0.07, all at the 3σCL. Additionally, we emphasize that there is significant room for new low energy physics, especially in the v τ sector which very few current experiments constrain directly.« less
Engineering criteria for fracture flowback procedures
DOE Office of Scientific and Technical Information (OSTI.GOV)
Barree, R.D.; Mukherjee, H.
1995-12-31
Post treatment fracture flowback procedures during closure are often critical to the retention of fracture conductivity near the wellbore. Postfrac production performance largely depends on this conductivity. The importance of proper flowback procedure has been documented in the fracture industry, but definitive guidelines for flowback design have never been established. As a result, many misconceptions exist regarding the physics of proppant flowback and its effects on the final proppant distribution in the fracture. This paper presents a rigorous study of fracture flowback and proppant migration during closure using a fully three-dimensional fracture geometry simulator (GOHFER). The effects of rate ofmore » flowback, location of the perforation interval, final proppant concentration, and the fracture geometry prior to flowback on the retained post closure proppant concentration are discussed. Consideration is given to the fluid velocity field in the created fracture resulting from the flowback, and its effects on proppant movement and localized fracture closure. These studies illustrate the difference between ``forced closure`` and ``reverse screenout`` concepts in flowback design. Other effects such as crossflow between multiple perforated layers are also studied. Simulation studies indicate that selection of a desirable flowback rate is very sensitive to crossflow effects resulting from induced fractures in multiple stress layers. This crossflow can result in significant overflushing of proppant in the lower stress zones, if not countered by properly applied flowback procedures.« less
Dubose, Joseph J; Scalea, Thomas M; Holcomb, John B; Shrestha, Binod; Okoye, Obi; Inaba, Kenji; Bee, Tiffany K; Fabian, Timothy C; Whelan, James; Ivatury, Rao R
2013-01-01
We conducted a prospective observational multi-institutional study to examine the natural history of the open abdomen (OA) after trauma and identify risk factors for failure to achieve definitive primary fascial closure (DPC) after OA use in trauma. Adults requiring OA for trauma were enrolled during a 2-year period. Demographics, presentation, and management variables were used to compare primary fascial closure and non-primary fascial closure patients, with logistic regression used to identify independent risk factors for failure to achieve primary fascial closure. A total of 572 patients from 14 American College of Surgeons-verified Level I trauma centers were enrolled. The majority were male (79%), mean (SD) age 39 (17) years. Injury Severity Score (ISS) was 15 or greater in 85% of patients and 84% had an abdominal Abbreviated Injury Scale (AIS) score of 3 or greater. Overall mortality was 23%. Initial primary fascial closure with unaltered native fascia was achieved in 379 patients (66%). Patients surviving at least 48 hours were grouped into those achieving DPC and those who did not achieve DPC after OA use. After logistic regression, independent risk factors for failure to achieve DPC included the number of reexplorations required (adjusted odds ratio [AOR], 1.3; 95% confidence interval (CI), 1.2-1.6; p < 0.001) the development of intra-abdominal abscess/sepsis (AOR, 2.4; 95% CI, 1.2-4.8; p = 0.011) bloodstream infection (AOR, 2.6; 95% CI, 1.2-5.7; p = 0.017), acute renal failure (AOR, 2.3; 95% CI, 1.2-5.7; p = 0.007), enteric fistula (AOR, 6.4; 95% CI, 1.2-32.8; p = 0.010) and ISS of greater than 15 (AOR, 2.5; 95% CI, 1.1-5.9; p = 0.037). Our study identifies independent risk factors associated with failure to achieve primary fascial closure during initial hospitalization after OA use for trauma. Additional study is required to validate appropriate algorithms that optimize the opportunity to achieve primary fascial closure and outcomes in this population. Prognostic study, level III.
NASA Astrophysics Data System (ADS)
Smidt, J.; Ingwersen, J.; Streck, T.
2015-12-01
The lack of energy balance closure is a long-standing problem in eddy covariance (EC) measurements. The energy balance equation is defined as Rn - G = H + λE, where Rn is net radiation, G is the ground heat flux, H is the sensible heat flux and λE is the latent heat flux. In most cases of energy imbalance, either Rn is overestimated or the ground heat and turbulent fluxes are underestimated. Multiple studies have shown that calculations, incorrect instrument installation/calibration and measurement errors alone do not entirely account for this imbalance. Rather, research is now focused on previously neglected sources of heat storage in the soil, biomass and air beneath the EC station. This project examined the potential of five "minor flux terms" - soil heat storage, biomass heat storage, energy consumption by photosynthesis, air heat storage and atmospheric moisture change, to further close the energy balance gap. Eddy covariance measurements were conducted at a maize (Zea mays) field in southwest Germany during summer 2014. Soil heat storage was measured for six weeks at 11 sites around the field footprint. Biomass and air heat storage were measured for six subsequent weeks at seven sites around the field footprint. Energy consumption by photosynthesis was calculated using the CO2 flux data. Evapotranspiration was calculated using the water balance method and then compared to the flux data processed with three post-closure methods: the sensible heat flux, the latent heat flux and the Bowen ratio post-closure methods. An energy balance closure of 66% was achieved by the EC station measurements over the entire investigation period. During the soil heat flux campaign, EC station closure was 74.1%, and the field footprint soil heat storage contributed 3.3% additional closure. During the second minor flux term measurement period, closure with the EC station data was 91%. Biomass heat storage resulted in 1.1% additional closure, the photosynthesis flux closed the gap by an additional 7.8%, air heat storage closure was -0.3% and atmospheric moisture change was negligible with an additional closure of <0.01%. These four terms resulted in a total additional closure of 8.6% over the EC station measurements. The Bowen Ratio post-closure method yielded values most similar to the water balance method over the entire season.
40 CFR 261.151 - Wording of the instruments.
Code of Federal Regulations, 2013 CFR
2013-07-01
... assurance for closure or post-closure care is demonstrated through the financial test specified in subpart H... parts 264 and 265. The current closure and/or post-closure cost estimates covered by such a test are... financial test specified in subpart H of 40 CFR parts 264 and 265. The current closure and/or post-closure...
50 CFR 660.360 - Recreational fishery-management measures.
Code of Federal Regulations, 2011 CFR
2011-10-01
... authorized for recreational fishing are hook-and-line and spear. Spears may be propelled by hand or by... when the closure is in effect. The closure is not in effect at this time. This closure may be imposed... when the closure is in effect. The closure is not in effect at this time. This closure may be imposed...
50 CFR 660.360 - Recreational fishery-management measures.
Code of Federal Regulations, 2012 CFR
2012-10-01
... authorized for recreational fishing are hook-and-line and spear. Spears may be propelled by hand or by... when the closure is in effect. The closure is not in effect at this time. This closure may be imposed... when the closure is in effect. The closure is not in effect at this time. This closure may be imposed...
Lee, David C; Carr, Brendan G; Smith, Tony E; Tran, Van C; Polsky, Daniel; Branas, Charles C
2015-12-01
Emergency visits are rising nationally, whereas the number of emergency departments is shrinking. However, volume has not increased uniformly at all emergency departments. It is unclear what factors account for this variability in emergency volume growth rates. The objective of this study was to test the association of hospital and population characteristics and the effect of hospital closures with increases in emergency department volume. The study team analyzed emergency department volume at New York State hospitals from 2004 to 2010 using data from cost reports and administrative databases. Multivariate regression was used to evaluate characteristics associated with emergency volume growth. Spatial analytics and distances between hospitals were used in calculating the predicted impact of hospital closures on emergency department use. Among the 192 New York hospitals open from 2004 to 2010, the mean annual increase in emergency department visits was 2.7%, but the range was wide (-5.5% to 11.3%). Emergency volume increased nearly twice as fast at tertiary referral centers (4.8%) and nonurban hospitals (3.7% versus urban at 2.1%) after adjusting for other characteristics. The effect of hospital closures also strongly predicted variation in growth. Emergency volume is increasing faster at specific hospitals: tertiary referral centers, nonurban hospitals, and those near hospital closures. This study provides an understanding of how emergency volume varies among hospitals and predicts the effect of hospital closures in a statewide region. Understanding the impact of these factors on emergency department use is essential to ensure that these populations have access to critical emergency services.
RUSSO, JOHN M.; FLORIAN, PETER; SHEN, LE; GRAHAM, W. VALLEN; TRETIAKOVA, MARIA S.; GITTER, ALFRED H.; MRSNY, RANDALL J.; TURNER, JERROLD R.
2005-01-01
Background & Aims Small epithelial wounds heal by purse-string contraction of an actomyosin ring that is regulated by myosin light chain (MLC) kinase (MLCK) and rho kinase (ROCK). These studies aimed to define the roles of these kinases in purse-string wound closure. Methods Oligocellular and single-cell wounds were created in intestinal epithelial monolayers. Fluorescence imaging and electrophysiologic data were collected during wound closure. Human biopsies were studied immunohistochemically. Results Live-cell imaging of enhanced green fluorescent protein-β-actin defined rapid actin ring assembly within 2 minutes after wounding. This progressed to a circumferential ring within 8 minutes that subsequently contracted and closed the wound. We therefore divided this process into 2 phases: ring assembly and wound contraction. Activated rho and ROCK localized to the wound edge during ring assembly. Consistent with a primary role in the assembly phase, ROCK inhibition prevented actin ring assembly and wound closure. ROCK inhibition after ring assembly was complete had no effect. Recruitment and activation of MLCK occurred after ring assembly was complete and coincided with ring contraction. MLCK inhibition slowed and then stopped contraction but did not prevent ring assembly. MLCK inhibition also delayed barrier function recovery. Studies of human colonic biopsy specimens suggest that purse-string wound closure also occurs in vivo, because MLC phosphorylation was enhanced surrounding oligocellular wounds. Conclusions These results suggest complementary roles for these kinases in purse-string closure of experimental and in vivo oligocellular epithelial wounds; rho and ROCK are critical for actin ring assembly, while the activity of MLCK drives contraction. PMID:15825080
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
This Closure Report provides documentation of the activities conducted during the Resource Conservation and Recovery Act (RCRA) closure of the Bitcutter and Postshot Containment Shops Injection Wells located in Area 2 of the Nevada Test Site (NTS), Oak Spring Quadrangle (USGS, 1986), Township 10 South, Range 53 East, Nye County, Nevada. This report discusses the Bitcutter Shop Inside Injection Well (CAU 90-A) closure-in-place and the Bitcutter Shop Outside Injection Well (CAU 90-B) and Postshot Containment Shop Injection Well (CAU 90-C) clean closures. This Closure Report provides background information about the unit, the results of the characterization activities and actions conductedmore » to determine the closure design. It also provides a discussion of the drainage analysis, preliminary closure activities, final closure activities, waste management activities, and the Post-Closure Care requirements.« less
Linearly exact parallel closures for slab geometry
NASA Astrophysics Data System (ADS)
Ji, Jeong-Young; Held, Eric D.; Jhang, Hogun
2013-08-01
Parallel closures are obtained by solving a linearized kinetic equation with a model collision operator using the Fourier transform method. The closures expressed in wave number space are exact for time-dependent linear problems to within the limits of the model collision operator. In the adiabatic, collisionless limit, an inverse Fourier transform is performed to obtain integral (nonlocal) parallel closures in real space; parallel heat flow and viscosity closures for density, temperature, and flow velocity equations replace Braginskii's parallel closure relations, and parallel flow velocity and heat flow closures for density and temperature equations replace Spitzer's parallel transport relations. It is verified that the closures reproduce the exact linear response function of Hammett and Perkins [Phys. Rev. Lett. 64, 3019 (1990)] for Landau damping given a temperature gradient. In contrast to their approximate closures where the vanishing viscosity coefficient numerically gives an exact response, our closures relate the heat flow and nonvanishing viscosity to temperature and flow velocity (gradients).
TECHNICAL ASPECTS OF UNDERGROUND STORAGE TANK CLOSURE
The overall objective of the study was to develop a deeper understanding of UST residuals at closure: their quantities, origins, physical/chemical properties, ease of removal by various cleaning methods, and their environmental mobility and persistence. The investigation covered ...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gonsalves, Michael, E-mail: drmag1975@gmail.com; Walkden, Miles, E-mail: rwalkden@nhs.net; Belli, Anna Maria, E-mail: Anna.Belli@stgeorges.nhs.u
2008-07-15
StarClose is a novel arterial closure device which achieves hemostasis, following arteriotomy, via a nitinol clip deployed on the outer arterial wall. Since its introduction to the market, several studies have shown StarClose to be both safe and effective, with few major complications encountered. We report a case of common femoral artery laceration following deployment of the StarClose vascular closure system. We conclude that the injury occurred secondary to intravascular misplacement of the nitinol clip.
Engineering study for closure of 209E facility
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brevick, C.H.; Heys, W.H.; Johnson, E.D.
1997-07-07
This document is an engineering study for evaluating alternatives to determine the most cost effective closure plan for the 209E Facility, Critical Mass Laboratory. This laboratory is located in the 200 East Area of the Hanford Site and contains a Critical Assembly Room and a Mix room were criticality experiments were once performed.
Park, Yulri; Choo, Sung Wook; Lee, Sung Hoon; Shin, Sung Wook; Do, Young Soo; Byun, Hong Sik; Park, Kwang Bo; Jeon, Pyoung
2005-01-01
Objective Rapid and effective hemostasis at femoral puncture sites minimizes both the hospital stay and patient discomfort. Therefore, a variety of arterial closure devices have been developed to facilitate the closure of femoral arteriotomy. The objective of this prospective study was to compare the efficacy of two different closure devices; a collagen plug device (Angio-Seal) and a suture-mediated closure device (the Closer S). Materials and Methods From March 28, 2003 to August 31, 2004, we conducted a prospective study in which 1,676 cases of 1,180 patients were treated with two different types of closure device. Angio-Seal was used in 961 cases and the Closer S in 715 cases. The efficacy of the closure devices was assessed, as well as complications occurring at the puncture sites. Results Successful immediate hemostasis was achieved in 95.2% of the cases treated with Angio-Seal, and in 89.5% of the cases treated with the Closer S (p < 0.05). The rates of minor and major complications occurring between the two groups were not significantly different. In the Closer S group, we observed four major complications (0.6%), that consisted of one massive retroperitoneal hemorrhage (surgically explored) and three pseudoaneurysms. In the Angio-Seal group, we observed three major complications (0.3%) that consisted of one femoral artery occlusion, one case of infection treated with intravenous antibiotics and one pseudoaneurysm. Conclusion The use of Angio-Seal was found to be more effective than that of the Closer S with regard to the immediate hemostasis of the femoral puncture sites. However, we detected no significant differences in the rate at which complications occurred. PMID:16374083
Cleft closure and undersizing annuloplasty improve mitral repair in atrioventricular canal defects
Padala, Muralidhar; Vasilyev, Nikolay V.; Owen, James W.; Jimenez, Jorge H.; Dasi, Lakshmi P.; del Nido, Pedro J.; Yoganathan, Ajit P.
2009-01-01
Objective Reoperation rates to correct left atrioventricular valve regurgitation after primary repair of atrioventricular canal defects remain relatively high. The causes of valvular regurgitation are likely multifactorial, and simple cleft closure is often insufficient to prevent recurrence. Methods To elucidate the mechanisms leading to regurgitation, we conducted hemodynamic studies using isolated native mitral valves. Anatomy of these valves was altered to mimic atrioventricular canal type valves and studied under pediatric hemodynamic conditions. The impact of subvalvular geometry, cleft closure, annular dilatation, and annular undersizing on regurgitation were investigated. Results Papillary muscle position did not have a significant effect on regurgitation. Cleft closure had a significant impact on valvular competence, with reduction in regurgitation volume with increased cleft closure. Regurgitation volume decreased from 12.5 ± 2.4 mL/beat for an open cleft to 4.9 ± 1.9 mL/beat for a partially closed cleft and to 1.4 ± 1.6 mL/beat when the cleft was completely closed. Annular dilatation had a significant impact on regurgitation even after cleft closure. A 40% increase in annular size increased regurgitation by 59% for a partially closed cleft and by 84% for a fully closed cleft. Reducing the annular size by 20% from the physiologic level decreased the regurgitation volume by 12% for a fully open cleft and by 58% for the partially closed cleft case. Conclusions Annular dilatation after primary repair has a potentially significant role in the recurrence of atrioventricular valve regurgitation. Reducing the annular size and restricting dilatation as an adjunct to cleft closure is a promising surgical approach in such valve anatomies. PMID:19026810
Long term cavity closure in salt using a Carreau viscosity model.
NASA Astrophysics Data System (ADS)
Cornet, Jan; Dabrowski, Marcin; Schmid, Daniel
2017-04-01
The problem of a pressurized hole in an infinite homogenous body is one of the most classical problems in geoscience. The solution is well-known when the rheology is linear but becomes much more complicated when applied to formations such as salt that can behave nonlinearly. Defining a constitutive law for the steady state deformation of salt is already a challenge and we rely on two deformation mechanisms - dislocation creep and pressure solution - to do that. More precisely, we use a Carreau model for viscosity to take into account in a single and smooth manner a linear and a nonlinear process. We use this rheology to revisit the classical two-dimensional problem of a pressurized cylindrical hole in an infinite and homogeneous body under general far field loads. We are interested in characterizing the maximum closure velocity at the rim. We provide analytical solutions for pressure and far field pure shear loads and we give a proxy for the general case based on the two end members. Using this general approach, we show that adding pressure solution to the constitutive law is especially important when studying long term hole closure under low pressure loads or when the grain size is in the order of 0.1 mm. Only considering dislocation creep can lead to underestimating the closure velocity by several orders of magnitude. Adding far field shear stress also dramatically enhances hole closure. The stress situation in salt bodies is often considered as isotropic but some shear exists at the interface between moving salt bodies and cap rock so pressurized holes in these regions experience increased closure. The analytical approach adopted in this study enables us to better understand the influence of all the input parameters on hole closure in salt.
Kheiri, Babikir; Abdalla, Ahmed; Osman, Mohammed; Ahmed, Sahar; Hassan, Mustafa; Bachuwa, Ghassan
2018-03-07
Cryptogenic strokes can be attributed to paradoxical emboli through patent foramen ovale (PFO). However, the effectiveness of PFO closure in preventing recurrent stroke is uncertain and the results of previous randomized clinical trials (RCTs) have been inconclusive. Hence, this study provides an updated meta-analysis of all RCTs comparing PFO closure with medical therapy for secondary prevention of cryptogenic stroke. All RCTs were identified by a comprehensive literature search of PubMed, Embase, the Cochrane Collaboration Central Register of Controlled Trials, Scopus, and Clinicaltrials.gov. The primary outcome was recurrent ischemic stroke and secondary outcomes were transient ischemic attack (TIA), all-cause mortality, new-onset atrial fibrillation (AF), serious adverse events, and major bleeding. 5 RCTs with 3440 participants were included in the present study (1829 patients underwent PFO closure and 1611 were treated medically). Pooled analysis showed a statistically significant reduction in the rate of recurrent stroke with PFO closure in comparison to medical therapy (OR 0.41; 95% CI 0.19-0.90; p = 0.03). However, there were no statistically significant reductions of recurrent TIAs (OR 0.77; 95% CI 0.51-1.14; p = 0.19) or all-cause mortality (OR 0.76; 95% CI 0.35-1.65; p = 0.48). The risk of developing new-onset AF was increased significantly with PFO closure (OR 4.74; 95% CI 2.33-9.61; p < 0.0001), but no significant differences in terms of serious adverse events or major bleeding between both groups. Patent foramen ovale closure in adults with recent cryptogenic stroke was associated with a lower rate of recurrent strokes in comparison with medical therapy alone.
Lower Hospital Charges and Societal Costs for Catheter Device Closure of Atrial Septal Defects.
Sanchez, Jessica N; Seckeler, Michael D
2017-10-01
Atrial septal defects (ASD) are among the most common congenital heart defects. As more ASDs are corrected by interventional catheterization instead of surgery, it is critical to understand the associated clinical and societal costs. The goal of this study was to use a national U.S. database to describe hospital charges and societal costs for surgical and catheter-based (ASD) closure. Retrospective review of hospital discharge data from the Kids' Inpatient Database from January 2010 to December 2012. The database was queried for admissions for <21 years old with ICD-9 procedure codes for surgical (35.51 or 35.61) or catheter (35.52) ASD closure; those with other cardiac conditions and/or additional cardiac procedures were excluded. Age, length of stay (LOS), and hospital charges and lost parental wages (societal costs) were compared between groups using t test or Mann-Whitney U test, as appropriate. Four hundred and eighty-six surgical and 305 catheter ASD closures were identified. LOS, hospital charges, and total societal costs were higher in surgical ASD compared to catheter ASD admissions (3.6 vs. 1.3 days, p < 0.001, $87,465 vs. $64,109, p < 0.001, and $90,000 vs. $64,966, p < 0.001, respectively). In this review of a large national inpatient database, we found that hospital and societal costs for surgical ASD closure are significantly higher than catheter ASD closure in the United States in the current era. Factors that likely contribute to this include longer LOS and longer post-operative recovery. Using "real-world" data, this study demonstrates a substantial cost advantage for catheter ASD closure compared to surgical.
Predictors of Salivary Fistulas in Patients Undergoing Salvage Total Laryngectomy
Wang, Steven J.
2014-01-01
Background. Salivary fistula is a common complication after salvage total laryngectomy. Previous studies have not considered the number of layers of pharyngeal closure and have not classified fistulas according to severity. Our objective was to analyze our institutional experience with salvage total laryngectomy, categorize salivary fistulas based on severity, and study the effect of various pharyngeal closure techniques on fistula incidence. Methods. Retrospective analysis of 48 patients who underwent salvage total laryngectomy, comparing pharyngeal closure technique and use of a pectoralis major flap with regard to salivary fistula rate. Fistulas were categorized into major and minor fistulas based on whether operative intervention was required. Results. The major fistula rate was 18.8% (9/48) and the minor fistula rate was 29.2% (14/48). The overall (major plus minor) fistula rate was 47.9%. The overall fistula and major fistula rates decreased with increasing the number of closure layers and with use of a pectoralis major flap; however, these correlations did not reach statistical significance. Other than age, there were no clinicopathologic variables associated with salivary fistulas. Conclusion. For salvage total laryngectomies, increasing the number of closure layers or use of a pectoralis major flap may reduce the risk of salivary fistula. PMID:27355065
Role of vortices in growth of microbubbles at mitral mechanical heart valve closure.
Rambod, Edmond; Beizai, Masoud; Sahn, David J; Gharib, Morteza
2007-07-01
This study is aimed at refining our understanding of the role of vortex formation at mitral mechanical heart valve (MHV) closure and its association with the high intensity transient signals (HITS) seen in echocardiographic studies with MHV recipients. Previously reported numerical results described a twofold process leading to formation of gas-filled microbubbles in-vitro: (1) nucleation and (2) growth of micron size bubbles. The growth itself consists of two processes: (a) diffusion and (b) sudden pressure drop due to valve closure. The role of diffusion has already been shown to govern the initial growth of nuclei. Pressure drop at mitral MHV closure may be attributed to other phenomena such as squeezed flow, water hammer and primarily, vortex cavitation. Mathematical analysis of vortex formation at mitral MHV closure revealed that a closing velocity of approximately 12 m/s can induce a strong regurgitant vortex which in return can instigate a local pressure drop of about 0.9 atm. A 2D experimental model of regurgitant flows was used to substantiate the impact of vortices. At simulated flow and pressure conditions, a regurgitant vortex was observed to drastically enlarge micron size hydrogen bubbles at its core.
Vaduganathan, Muthiah; Qamar, Arman; Gupta, Ankur; Bajaj, Navkaranbir; Golwala, Harsh B; Pandey, Ambarish; Bhatt, Deepak L
2018-05-01
Patent foramen ovale closure represents a potential secondary prevention strategy for cryptogenic stroke, but available trials have varied by size, device studied, and follow-up. We conducted a systematic search of published randomized clinical trials evaluating patent foramen ovale closure versus medical therapy in patients with recent stroke or transient ischemic attack using PubMED, EMBASE, and Cochrane through September 2017. Weighting was by random effects models. Of 480 studies screened, we included 5 randomized clinical trials in the meta-analysis in which 3440 patients were randomized to patent foramen ovale closure (n = 1829) or medical therapy (n = 1611) and followed for an average of 2.0 to 5.9 years. Index stroke/transient ischemic attack occurred within 6 to 9 months of randomization. The primary end point was composite stroke/transient ischemic attack and death (in 3 trials) or stroke alone (in 2 trials). Patent foramen ovale closure reduced the primary end point (0.70 vs 1.48 events per 100 patient-years; risk ratio [RR], 0.52 [0.29-0.91]; I 2 = 55.0%) and stroke/transient ischemic attack (1.04 vs 2.00 events per 100 patient-years; RR, 0.55 [0.37-0.82]; I 2 = 42.2%) with modest heterogeneity compared with medical therapy. Procedural bleeding was not different between study arms (1.8% vs 1.8%; RR, 0.94 [0.49-1.83]; I 2 = 29.2%), but new-onset atrial fibrillation/flutter was increased with patent foramen ovale closure (6.6% vs 0.7%; RR, 4.69 [2.17-10.12]; I 2 = 29.3%). In patients with recent cryptogenic stroke, patent foramen ovale closure reduces recurrent stroke/transient ischemic attack compared with medical therapy, but is associated with a higher risk of new-onset atrial fibrillation/flutter. Copyright © 2018 Elsevier Inc. All rights reserved.
Xhepa, Erion; Byrne, Robert A; Schulz, Stefanie; Helde, Sandra; Gewalt, Senta; Cassese, Salvatore; Linhardt, Maryam; Ibrahim, Tareq; Mehilli, Julinda; Hoppe, Katharina; Grupp, Katharina; Kufner, Sebastian; Böttiger, Corinna; Hoppmann, Petra; Burgdorf, Christof; Fusaro, Massimiliano; Ott, Ilka; Schneider, Simon; Hengstenberg, Christian; Schunkert, Heribert; Laugwitz, Karl-Ludwig; Kastrati, Adnan
2014-06-01
Vascular closure devices (VCD) have been introduced into clinical practice with the aim of increasing the procedural efficiency and clinical safety of coronary angiography. However, clinical studies comparing VCD and manual compression have yielded mixed results, and large randomised clinical trials comparing the two strategies are missing. Moreover, comparative efficacy studies between different VCD in routine clinical use are lacking. The Instrumental Sealing of ARterial puncture site - CLOSURE device versus manual compression (ISAR-CLOSURE) trial is a prospective, randomised clinical trial designed to compare the outcomes associated with the use of VCD or manual compression to achieve femoral haemostasis. The test hypothesis is that femoral haemostasis after coronary angiography achieved using VCD is not inferior to manual compression in terms of access-site-related vascular complications. Patients undergoing coronary angiography via the common femoral artery will be randomised in a 1:1:1 fashion to receive FemoSeal VCD, EXOSEAL VCD or manual compression. The primary endpoint is the incidence of the composite of arterial access-related complications (haematoma ≥5 cm, pseudoaneurysm, arteriovenous fistula, access-site-related bleeding, acute ipsilateral leg ischaemia, the need for vascular surgical/interventional treatment or documented local infection) at 30 days after randomisation. According to power calculations based on non-inferiority hypothesis testing, enrolment of 4,500 patients is planned. The trial is registered at www.clinicaltrials.gov (study identifier: NCT01389375). The safety of VCD as compared to manual compression in patients undergoing transfemoral coronary angiography remains an issue of clinical equipoise. The aim of the ISAR-CLOSURE trial is to assess whether femoral haemostasis achieved through the use of VCD is non-inferior to manual compression in terms of access-site-related vascular complications.
System for closure of a physical anomaly
Bearinger, Jane P; Maitland, Duncan J; Schumann, Daniel L; Wilson, Thomas S
2014-11-11
Systems for closure of a physical anomaly. Closure is accomplished by a closure body with an exterior surface. The exterior surface contacts the opening of the anomaly and closes the anomaly. The closure body has a primary shape for closing the anomaly and a secondary shape for being positioned in the physical anomaly. The closure body preferably comprises a shape memory polymer.
Infering and Calibrating Triadic Closure in a Dynamic Network
NASA Astrophysics Data System (ADS)
Mantzaris, Alexander V.; Higham, Desmond J.
In the social sciences, the hypothesis of triadic closure contends that new links in a social contact network arise preferentially between those who currently share neighbours. Here, in a proof-of-principle study, we show how to calibrate a recently proposed evolving network model to time-dependent connectivity data. The probabilistic edge birth rate in the model contains a triadic closure term, so we are also able to assess statistically the evidence for this effect. The approach is shown to work on data generated synthetically from the model. We then apply this methodology to some real, large-scale data that records the build up of connections in a business-related social networking site, and find evidence for triadic closure.
Uy, Harvey S; Kenyon, Kenneth R
2013-11-01
To compare the anatomic and refractive outcomes in eyes having phacoemulsification with 1 of 3 clear corneal incision (CCI) closure methods. Ambulatory surgical center, Makati, Philippines. Prospective randomized clinical trial. Patients having phacoemulsification cataract surgery had wound closure using no additional treatment (control), a single 10-0 nylon suture, or a liquid adhesive ocular bandage (Ocuseal). The main outcome measures were wound-edge closure rates, surgically induced astigmatism (SIA), foreign-body sensation, and intraocular pressure (IOP) 1, 3, 5, 7, and 14 days postoperatively. The study evaluated 90 eyes. There was a significant improvement in wound-edge closure rates in the suture group and the ocular bandage group compared with the control group (P<.001). A significant increase in SIA occurred in the sutured group but not in the control or ocular bandage groups (P<.001). The ocular bandage group had significantly less foreign-body sensation than the control and suture groups (P<.001). There were no significant differences in IOP between the groups (P=.515). The liquid adhesive ocular bandage resulted in improved wound-edge closure, reduced SIA, and diminished foreign-body sensation. Suturing was associated with improved wound-edge closure but increased SIA and foreign-body sensation. Unsutured incisions led to delayed wound-edge closure and increased foreign-body sensation. Copyright © 2013 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.
Izumi, Yotaro; Kawamura, Masafumi; Gika, Masatoshi; Nomori, Hiroaki
2010-03-01
The aim of this study was to compare the morphology of the bronchial stump after lobectomy between mechanical stapler closure and manual suture closure. The effect of fibrin glue application on each method of closure was also observed. Right upper lobectomy was performed in beagles (n=31) using staplers (ST group) or sutures (SU group). In a separate experiment, fibrin glue was sprayed onto the stump after each respective method of closure. After one week, the stump region was examined macroscopically, and also by histology. chi(2)-Test and Mann-Whitney test were used for comparative analysis. The incidence of adhesion formation between the surrounding tissues was significantly reduced in the ST group in comparison to the SU group (22 vs. 80%, P=0.04). The thickness of granulation tissue over the stump was significantly reduced in the ST group in comparison to the SU group (0.8+/-0.2 vs. 2.5+/-0.3 mm, P<0.0001). Vessel density in the granulation tissue was also significantly reduced in the ST group in comparison to the SU group (6+/-2 vs. 16+/-2, P=0.003). Fibrin glue application after stapler closure significantly increased the incidence of adhesion formation, granulation tissue thickness, and vessel density in the granulation tissue over the stump.
Nongpiur, Monisha E; Haaland, Benjamin A; Perera, Shamira A; Friedman, David S; He, Mingguang; Sakata, Lisandro M; Baskaran, Mani; Aung, Tin
2014-01-01
To develop a score along with an estimated probability of disease for detecting angle closure based on anterior segment optical coherence tomography (AS OCT) imaging. Cross-sectional study. A total of 2047 subjects 50 years of age and older were recruited from a community polyclinic in Singapore. All subjects underwent standardized ocular examination including gonioscopy and imaging by AS OCT (Carl Zeiss Meditec). Customized software (Zhongshan Angle Assessment Program) was used to measure AS OCT parameters. Complete data were available for 1368 subjects. Data from the right eyes were used for analysis. A stepwise logistic regression model with Akaike information criterion was used to generate a score that then was converted to an estimated probability of the presence of gonioscopic angle closure, defined as the inability to visualize the posterior trabecular meshwork for at least 180 degrees on nonindentation gonioscopy. Of the 1368 subjects, 295 (21.6%) had gonioscopic angle closure. The angle closure score was calculated from the shifted linear combination of the AS OCT parameters. The score can be converted to an estimated probability of having angle closure using the relationship: estimated probability = e(score)/(1 + e(score)), where e is the natural exponential. The score performed well in a second independent sample of 178 angle-closure subjects and 301 normal controls, with an area under the receiver operating characteristic curve of 0.94. A score derived from a single AS OCT image, coupled with an estimated probability, provides an objective platform for detection of angle closure. Copyright © 2014 Elsevier Inc. All rights reserved.
Tissue adhesives for closure of surgical incisions.
Dumville, Jo C; Coulthard, Paul; Worthington, Helen V; Riley, Philip; Patel, Neil; Darcey, James; Esposito, Marco; van der Elst, Maarten; van Waes, Oscar J F
2014-11-28
Sutures (stitches), staples and adhesive tapes have been used for many years as methods of wound closure, but tissue adhesives have entered clinical practice more recently. Closure of wounds with sutures enables the closure to be meticulous, but the sutures may show tissue reactivity and can require removal. Tissue adhesives offer the advantages of an absence of risk of needlestick injury and no requirement to remove sutures later. Initially, tissue adhesives were used primarily in emergency room settings, but this review looks at the use of tissue adhesives in the operating room/theatre where surgeons are using them increasingly for the closure of surgical skin incisions. To determine the effects of various tissue adhesives compared with conventional skin closure techniques for the closure of surgical wounds. In March 2014 for this second update we searched the Cochrane Wounds Group Specialised Register; The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library); Ovid MEDLINE; Ovid MEDLINE (In-Process & Other Non-Indexed Citations); Ovid EMBASE and EBSCO CINAHL. We did not restrict the search and study selection with respect to language, date of publication or study setting. Only randomised controlled trials were eligible for inclusion. We conducted screening of eligible studies, data extraction and risk of bias assessment independently and in duplicate. We expressed results as random-effects models using mean difference for continuous outcomes and risk ratios (RR) with 95% confidence intervals (CI) for dichotomous outcomes. We investigated heterogeneity, including both clinical and methodological factors. This second update of the review identified 19 additional eligible trials resulting in a total of 33 studies (2793 participants) that met the inclusion criteria. There was low quality evidence that sutures were significantly better than tissue adhesives for reducing the risk of wound breakdown (dehiscence; RR 3.35; 95% CI 1.53 to 7.33; 10 trials, 736 participants that contributed data to the meta-analysis). The number needed to treat for an additional harmful outcome was calculated as 43. For all other outcomes - infection, patient and operator satisfaction and cost - there was no evidence of a difference for either sutures or tissue adhesives. No evidence of differences was found between tissue adhesives and tapes for minimising dehiscence, infection, patients' assessment of cosmetic appearance, patient satisfaction or surgeon satisfaction. However there was evidence in favour of using tape for surgeons' assessment of cosmetic appearance (mean difference (VAS 0 to 100) 9.56 (95% CI 4.74 to 14.37; 2 trials, 139 participants). One trial compared tissue adhesives with a variety of methods of wound closure and found both patients and clinicians were significantly more satisfied with the alternative closure methods than the adhesives. There appeared to be little difference in outcome for different types of tissue adhesives. One study that compared high viscosity with low viscosity adhesives found that high viscosity adhesives were less time-consuming to use than low viscosity tissue adhesives, but the time difference was small. Sutures are significantly better than tissue adhesives for minimising dehiscence. In some cases tissue adhesives may be quicker to apply than sutures. Although surgeons may consider the use of tissue adhesives as an alternative to other methods of surgical site closure in the operating theatre, they need to be aware that sutures minimise dehiscence. There is a need for more well designed randomised controlled trials comparing tissue adhesives with alternative methods of closure. These trials should include people whose health may interfere with wound healing and surgical sites of high tension.
Numerical study of a separating and reattaching flow by using Reynolds-stress tubulence closure
NASA Technical Reports Server (NTRS)
Amano, R. S.; Goel, P.
1983-01-01
The numerical study of the Reynolds-stress turbulence closure for separating, reattaching, recirculating and redeveloping flow is summarized. The calculations were made for two different closure models of pressure - strain correlation. The results were compared with the experimental data. Furthermore, these results were compared with the computations made by using the one layer and three layer treatment of k-epsilon turbulence model which were developed. Generally the computations by the Reynolds-stress model show better results than those by the k-epsilon model, in particular, some improvement was noticed in the redeveloping region of the separating and reattaching flow in a pipe with sudden expansion.
Casson, R J; Newland, H S; Muecke, J; McGovern, S; Abraham, L M; Shein, W K; Selva, D; Aung, T
2007-01-01
Aim To determine the prevalence of preglaucomatous angle‐closure disease in central Myanmar. Methods A population‐based survey of inhabitants ⩾40 years in the Meiktila District was carried out; 2481 subjects were identified, 2076 participated and 2060 underwent gonioscopy of at least one eye. Eyes with angles traditionally described as “occludable” were recorded as primary angle‐closure suspects (PACS); eyes with PACS and peripheral anterior synechiae (PAS), or an increased intraocular pressure but without primary angle‐closure glaucoma, were recorded as primary angle closure (PAC). Results The prevalence of PACS in at least one eye was 5.7% (95% CI 4.72 to 6.62); prevalence increased with age and was more common in women (p<0.001). The prevalence of PAC in at least one eye was 1.50% (95% CI 1.47 to 1.53). All participants with PAS had at least 90° of closure (range 90–360°). Conclusion The prevalence of preglaucomatous angle‐closure disease (PACS and PAC) in this population was 5.7% and 1.5%, respectively. PACS was more common in women, and its prevalence increased with age. PMID:17576708
A nonlocal fluid closure for antiparallel reconnection
NASA Astrophysics Data System (ADS)
Ng, J.; Hakim, A.; Bhattacharjee, A.
2016-12-01
The integration of kinetic effects in fluid models is an important problem in global simulations of the Earth's magnetosphere and space weather modelling. In particular, it has been shown that ion kinetics play an important role in the dynamics of large reconnecting systems, and that fluid models can account of some of these effects[1,2] . Here we introduce a new fluid model and closure for collisionless magnetic reconnection and more general applications. Taking moments of the kinetic equation, we evolve the full pressure tensor for electrons and ions, which includes the off diagonal terms necessary for reconnection. Kinetic effects are recovered by using a nonlocal heat flux closure, which approximates linear Landau damping in the fluid framework [3]. Using the island coalescence problem as a test, we show how the nonlocal ion closure improves on the typical collisional closures used for ten-moment models and circumvents the need for a colllisional free parameter. Finally, we extend the closure to study guide-field reconnection and discuss the implementation of a twenty-moment model.[1] A. Stanier et al. Phys Rev Lett (2015)[2] J. Ng et al. Phys Plasmas (2015)[3] G. Hammett et al. Phys Rev Lett (1990)
Weiss, Dawn M; Kaiser, Jeffrey R; Swearingen, Christopher; Malik, Sadia; Sachdeva, Ritu
2015-11-01
This study aims to determine echocardiographic parameters associated with spontaneous patent ductus arteriosus (PDA) closure in extremely low-birth-weight (ELBW) infants. Retrospective demographic review and analysis of echocardiograms from 189 ELBW infants with suspected and confirmed hemodynamically significant PDA identified on an initial echocardiogram was performed. Comparison of echocardiographic parameters was made between infants with spontaneous closure versus those who received treatment. The mean birth weight (787 ± 142 vs. 724 ± 141 g, p = 0.04) and gestational age (27.4 ± 2.8 vs. 26.2 ± 1.6 weeks, p = 0.03) were higher in the spontaneous closure versus the treatment group. Antegrade pulmonary artery (PA) diastolic velocity was lower in infants with spontaneous PDA closure versus those who received treatment (0.15 ± 0.06 vs. 0.22 ± 0.12 m/s, p = 0.009). Heavier and more mature ELBW infants with a lower antegrade PA diastolic velocity were likely to have spontaneous closure of the PDA. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
Moore, John W; Greene, Jessica; Palomares, Salvadore; Javois, Alexander; Owada, Carl Y; Cheatham, John P; Hoyer, Mark H; Jones, Thomas K; Levi, Daniel S
2014-12-01
This study aimed to compare the efficacy and safety of the Nit-Occlud PDA device (PFM Medical, Cologne, Germany) to benchmarks designed as objective performance criteria (OPC). The Nit-Occlud PDA is a nitinol coil-type patent ductus arteriosus (PDA) occluder with a reverse cone configuration, which is implanted using a controlled delivery system. Patients with <4-mm minimum diameter PDA were prospectively enrolled in the Pivotal and the Continuing Access Studies from 15 sites in the United States and were followed up for 12 months post-procedure. Investigator-reported outcomes were compared to OPC including a composite success criterion, efficacy criteria of successful closure (clinical and echocardiographic), and safety criteria incidence of adverse events (serious and of total). The Pivotal Study enrolled patients between November 1, 2002 and October 31, 2005, and the Continuing Access Study enrolled additional patients between September 1, 2006 and October 31, 2007. A total of 357 patients were enrolled, and 347 had successful device implantations. After 12 months, 96.8% had complete echocardiographic closure (OPC = 85%) and 98.1% had clinical closure (OPC = 95%). There were no deaths or serious adverse events (OPC = 1%). The total adverse event rate was 4.7% (OPC = 6%). Composite success was 95.1% in the study patients (OPC = 80%). Closure of small- and medium-sized PDA with the Nit-Occlud PDA is effective and safe when compared with OPC. Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
Commercial Submersible Mixing Pump For SRS Tank Waste Removal - 15223
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hubbard, Mike; Herbert, James E.; Scheele, Patrick W.
The Savannah River Site Tank Farms have 45 active underground waste tanks used to store and process nuclear waste materials. There are 4 different tank types, ranging in capacity from 2839 m 3 to 4921 m 3 (750,000 to 1,300,000 gallons). Eighteen of the tanks are older style and do not meet all current federal standards for secondary containment. The older style tanks are the initial focus of waste removal efforts for tank closure and are referred to as closure tanks. Of the original 51 underground waste tanks, six of the original 24 older style tanks have completed waste removalmore » and are filled with grout. The insoluble waste fraction that resides within most waste tanks at SRS requires vigorous agitation to suspend the solids within the waste liquid in order to transfer this material for eventual processing into glass filled canisters at the Defense Waste Processing Facility (DWPF). SRS suspends the solid waste by use of recirculating mixing pumps. Older style tanks generally have limited riser openings which will not support larger mixing pumps, since the riser access is typically 58.4 cm (23 inches) in diameter. Agitation for these tanks has been provided by four long shafted standard slurry pumps (SLP) powered by an above tank 112KW (150 HP) electric motor. The pump shaft is lubricated and cooled in a pressurized water column that is sealed from the surrounding waste in the tank. Closure of four waste tanks has been accomplished utilizing long shafted pump technology combined with heel removal using multiple technologies. Newer style waste tanks at SRS have larger riser openings, allowing the processing of waste solids to be accomplished with four large diameter SLPs equipped with 224KW (300 HP) motors. These tanks are used to process the waste from closure tanks for DWPF. In addition to the SLPs, a 224KW (300 HP) submersible mixer pump (SMP) has also been developed and deployed within older style tanks. The SMPs are product cooled and product lubricated canned motor pumps designed to fit within available risers and have significant agitation capabilities to suspend waste solids. Waste removal and closure of two tanks has been accomplished with agitation provided by 3 SMPs installed within the tanks. In 2012, a team was assembled to investigate alternative solids removal technologies to support waste removal for closing tanks. The goal of the team was to find a more cost effective approach that could be used to replace the current mixing pump technology. This team was unable to identify an alternative technology outside of mixing pumps to support waste agitation and removal from SRS waste tanks. However, the team did identify a potentially lower cost mixing pump compared to the baseline SLPs and SMPs. Rather than using the traditional procurement using an engineering specification, the team proposed to seek commercially available submersible mixer pumps (CSMP) as alternatives to SLPs and SMPs. SLPs and SMPs have a high procurement cost and the actual cost of moving pumps between tanks has shown to be significantly higher than the original estimates that justified the reuse of SMPs and SLPs. The team recommended procurement of “off-the-shelf” industry pumps which may be available for significant savings, but at an increased risk of failure and reduced operating life in the waste tank. The goal of the CSMP program is to obtain mixing pumps that could mix from bulk waste removal through tank closure and then be abandoned in place as part of tank closure. This paper will present the development, progress and relative advantages of the CSMP.« less
40 CFR 264.258 - Closure and post-closure care.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Waste Piles § 264.258 Closure and post-closure care. (a) At closure, the owner or operator must remove... that apply to landfills (§ 264.310). (c)(1) The owner or operator of a waste pile that does not comply...(c) or § 264.251(b), must: (i) Include in the closure plan for the pile under § 264.112 both a plan...
APPARATUS AND METHOD FOR WELDING END CLOSURE TO CONTAINER
Frantz, C.E.; Correy, T.B.
1959-08-01
A semi-automatic apparatus is described for welding a closure to the open end of a can containing a nuclear fuel slug. An arc is struck at the center of the closure and is shifted to a region near its periphery. Then the assembly of closure, can, and fuel slug is rotated so that the peripheral region of the closure is preheated. Next the arc is shifted to the periphery itself of the closure, and the assembly is rotated so that the closure is welded to the can.
Oliver, Thomas A; Oleson, Kirsten L L; Ratsimbazafy, Hajanaina; Raberinary, Daniel; Benbow, Sophie; Harris, Alasdair
2015-01-01
Eight years of octopus fishery records from southwest Madagascar reveal significant positive impacts from 36 periodic closures on: (a) fishery catches and (b) village fishery income, such that (c) economic benefits from increased landings outweigh costs of foregone catch. Closures covered ~20% of a village's fished area and lasted 2-7 months. Octopus landings and catch per unit effort (CPUE) significantly increased in the 30 days following a closure's reopening, relative to the 30 days before a closure (landings: +718%, p<0.0001; CPUE: +87%, p<0.0001; n = 36). Open-access control sites showed no before/after change when they occurred independently of other management ("no ban", n = 17/36). On the other hand, open-access control sites showed modest catch increases when they extended a 6-week seasonal fishery shutdown ("ban", n = 19/36). The seasonal fishery shutdown affects the entire region, so confound all potential control sites. In villages implementing a closure, octopus fishery income doubled in the 30 days after a closure, relative to 30 days before (+132%, p<0.001, n = 28). Control villages not implementing a closure showed no increase in income after "no ban" closures and modest increases after "ban" closures. Villages did not show a significant decline in income during closure events. Landings in closure sites generated more revenue than simulated landings assuming continued open-access fishing at that site (27/36 show positive net earnings; mean +$305/closure; mean +57.7% monthly). Benefits accrued faster than local fishers' time preferences during 17-27 of the 36 closures. High reported rates of illegal fishing during closures correlated with poor economic performance. We discuss the implications of our findings for broader co-management arrangements, particularly for catalyzing more comprehensive management.
New Mexico's 1998 drive-up liquor window closure. Study II: economic impact on owners.
Lapham, Sandra C; Skipper, Betty J
2004-05-01
This study examined the economic impact of the New Mexico legislative action closing drive-up liquor windows on the retail establishments that operated them. A telephone survey was conducted 20 months after the closure seeking information and owners' opinions about how their outlets had changed since the closure and how this affected their business. In addition, 2 years of aggregated pre- and post-closure total gross receipts revenues were obtained from the New Mexico Taxation and Revenue Department, with convenience stores as a comparison group. Interviews were completed for 149 of 220 establishments. Over one-quarter of former drive-up liquor windows (28%) had been converted to 'step-in' sales, defined as an outside door where customers can stop and enter the premises while their car is running. Almost two-thirds (61%) of owners reported decreased annual gross revenues following closure, with a reported average 15% reduction in alcohol sales. This is consistent with findings of decreased gross receipts for operators of non-urban, but not urban, drive-up liquor windows compared to convenience store gross receipts. Almost three-quarters (72%) of those surveyed would re-open the drive-up window if the law were rescinded. Over one-quarter of the drive-up owners converted to step-in alcohol sales that still allow a form of drive-up liquor sales. Despite this, the forced closure of New Mexico's drive-up liquor windows negatively impacted total sales and liquor sales revenues of establishments that operated them.
Managing hospitals in turbulent times: do organizational changes improve hospital survival?
Lee, S Y; Alexander, J A
1999-01-01
OBJECTIVE: To examine (1) the degree to which organizational changes affected hospital survival; (2) whether core and peripheral organizational changes affected hospital survival differently; and (3) how simultaneous organizational changes affected hospital survival. DATA SOURCES: AHA Hospital Surveys, the Area Resource File, and the AHA Hospital Guides, Part B: Multihospital Systems. STUDY DESIGN: The study employed a longitudinal panel design. We followed changes in all community hospitals in the continental United States from 1981 through 1994. The dependent variable, hospital closure, was examined as a function of multiple changes in a hospital's core and peripheral structures as well as the hospital's organizational and environmental characteristics. Cox regression models were used to test the expectations that core changes increased closure risk while peripheral changes decreased such risk, and that simultaneous core and peripheral changes would lead to higher risk of closure. PRINCIPAL FINDINGS: Results indicated more peripheral than core changes in community hospitals. Overall, findings contradicted our expectations. Change in specialty, a core change, was beneficial for hospitals, because it reduced closure risk. The two most frequent peripheral changes, downsizing and leadership change, were positively associated with closure. Simultaneous organizational changes displayed a similar pattern: multiple core changes reduced closure risk, while multiple peripheral changes increased the risk. These patterns held regardless of the level of uncertainty in hospital environments. CONCLUSIONS: Organizational changes are not all beneficial for hospitals, suggesting that hospital leaders should be both cautious and selective in their efforts to turn their hospitals around. PMID:10536977
Economic and health risk trade-offs of swim closures at a Lake Michigan beach
Rabinovici, Sharyl M.; Bernknopf, Richard L.; Wein, Anne M.; Coursey, Don L.; Whitman, Richard L.
2004-01-01
This paper presents a framework for analyzing the economic, health, and recreation implications of swim closures related to high fecal indicator bacteria (FIB) levels. The framework utilizes benefit transfer policy analysis to provide a practical procedure for estimating the effectiveness of recreational water quality policies. Evaluation criteria include the rates of intended and unintended management outcomes, whether the chosen protocols generate closures with positive net economic benefits to swimmers, and the number of predicted illnesses the policy is able to prevent. We demonstrate the framework through a case study of a Lake Michigan freshwater beach using existing water quality and visitor data from 1998 to 2001. We find that a typical closure causes a net economic loss among would-be swimmers totaling $1274-37 030/ day, depending on the value assumptions used. Unnecessary closures, caused by high indicator variability and a 24-h time delay between when samples are taken and the management decision can be made, occurred on 14 (12%) out of 118 monitored summer days. Days with high FIB levels when the swim area is open are also common but do relatively little economic harm in comparison. Also, even if the closure policy could be implemented daily and perfectly without error, only about 42% of predicted illnesses would be avoided. These conclusions were sensitive to the relative values and risk preferences that swimmers have for recreation access and avoiding health effects, suggesting a need for further study of the impacts of recreational water quality policies on individuals.
The Rising Rate of Rural Hospital Closures.
Kaufman, Brystana G; Thomas, Sharita R; Randolph, Randy K; Perry, Julie R; Thompson, Kristie W; Holmes, George M; Pink, George H
2016-01-01
Since 2010, the rate of rural hospital closures has increased significantly. This study is a preliminary look at recent closures and a formative step in research to understand the causes and the impact on rural communities. The 2009 financial performance and market characteristics of rural hospitals that closed from 2010 through 2014 were compared to rural hospitals that remained open during the same period, stratified by critical access hospitals (CAHs) and other rural hospitals (ORHs). Differences were tested using Pearson's chi-square (categorical variables) and Wilcoxon rank test of medians. The relationships between negative operating margin and (1) market factors and (2) utilization/staffing factors were explored using logistic regression. In 2009, CAHs that subsequently closed from 2010 through 2014 had, in general, lower levels of profitability, liquidity, equity, patient volume, and staffing. In addition, ORHs that closed had smaller market shares and operated in markets with smaller populations compared to ORHs that remained open. Odds of unprofitability were associated with both market and utilization factors. Although half of the closed hospitals ceased providing health services altogether, the remainder have since converted to an alternative health care delivery model. Financial and market characteristics appear to be associated with closure of rural hospitals from 2010 through 2014, suggesting that it is possible to identify hospitals at risk of closure. As closure rates show no sign of abating, it is important to study the drivers of distress in rural hospitals, as well as the potential for alternative health care delivery models. © 2015 National Rural Health Association.
Xiao, H; Sorofman, B; Manasse, H R
2000-03-01
The objectives of this study were 2-fold: (1) to examine the association of pharmacy closures with prescription drug use by Medicaid recipients in Iowa; and (2) to evaluate how drug utilization patterns differ between patients whose pharmacies closed and patients whose pharmacies remained open. A 2-group pretest-posttest study of Medicaid enrollees who may have been affected by pharmacy closures. Prescription medication use during the periods preceding and after pharmacy closures was compared. A comparison group was used to account for extraneous factors. Sixteen community pharmacies were selected from a pool of pharmacies that closed during 1994; 1092 patients were identified as the main users of these pharmacies, and a comparison group of 3491 patients whose main pharmacies had not closed also was identified. The average number of each patient's prescription claims for the 6 months preceding closing and the 6 months after closing was computed. Multiple regression analysis was conducted to determine whether any association existed between pharmacy closures and the use of prescription drugs. Patients whose pharmacies closed during 1994 had fewer prescription claims after the closings than before the closings. In contrast, patients whose pharmacies remained open had more prescription claims. This difference remains statistically significant after controlling for other factors, such as patient demographics and health status. A decrease in prescription drug use was associated with pharmacy closures. Attention should be directed to patient access to prescription medications in rural areas, as relatively more pharmacies close in rural areas.
40 CFR 264.280 - Closure and post-closure care.
Code of Federal Regulations, 2013 CFR
2013-07-01
... Section 264.280 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES Land Treatment § 264.280 Closure and post-closure care. (a) During the closure period the owner or...
40 CFR 264.280 - Closure and post-closure care.
Code of Federal Regulations, 2011 CFR
2011-07-01
... Section 264.280 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES Land Treatment § 264.280 Closure and post-closure care. (a) During the closure period the owner or...
40 CFR 264.280 - Closure and post-closure care.
Code of Federal Regulations, 2012 CFR
2012-07-01
... Section 264.280 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES Land Treatment § 264.280 Closure and post-closure care. (a) During the closure period the owner or...
40 CFR 264.280 - Closure and post-closure care.
Code of Federal Regulations, 2014 CFR
2014-07-01
... Section 264.280 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES Land Treatment § 264.280 Closure and post-closure care. (a) During the closure period the owner or...
Metalloproteinase Expression is Associated with Traumatic Wound Failure
2010-04-01
Traumatic amputation- no.(%) 15 Size of wound (cm3 )* Associated vascular injury- no.(%) 7 Wound closure method no.(%) Suture 29 Skin graft 9 Number...definitive closure or coverage with skin graft . Im- paired wound healing included delayed wound closure or wound dehiscence after closure or coverage...closure time period of 10 d. Dehiscence was defined as spontaneous partial or com- plete wound disruption after primary closure or > 90% skin graft loss
Critical factors in displacement ductility assessment of high-strength concrete columns
NASA Astrophysics Data System (ADS)
Taheri, Ali; Moghadam, Abdolreza S.; Tasnimi, Abass Ali
2017-12-01
Ductility of high-strength concrete (HSC) columns with rectangular sections was assessed in this study by reviewing experimental data from the available literature. Up to 112 normal weights concrete columns with strength in the range of 50-130 MPa were considered and presented as a database. The data included the results of column testes under axial and reversed lateral loading. Displacement ductility of HSC columns was evaluated in terms of their concrete and reinforcement strengths, bar arrangement, volumetric ratio of transverse reinforcement, and axial loading. The results indicated that the confinement requirements and displacement ductility in HSC columns are more sensitive than those in normal strength concrete columns. Moreover, ductility is descended by increasing concrete strength. However, it was possible to obtain ductile behavior in HSC columns through proper confinement. Furthermore, this study casts doubt about capability of P/ A g f c' ratio that being inversely proportional to displacement ductility of HSC columns.
Novel application of polyelectrolyte multilayers as nanoscopic closures with hermetic sealing.
Marcott, Stephanie A; Ada, Sena; Gibson, Phillip; Camesano, Terri A; Nagarajan, R
2012-03-01
Closure systems for personnel protection applications, such as protective clothing or respirator face seals, should provide effective permeation barrier to toxic gases. Currently available mechanical closure systems based on the hook and loop types (example, Velcro) do not provide adequate barrier to gas permeation. To achieve hermetic sealing, we propose a nonmechanical, nanoscopic molecular closure system based on complementary polyelectrolyte multilayers, one with a polycation outermost layer and the other with a polyanion outermost layer. The closure surfaces were prepared by depositing polyelectrolyte multilayers under a variety of deposition conditions, on conformable polymer substrates (thin films of polyethylene teraphthalate, PET or polyimide, PI). The hermetic sealing property of the closures was evaluated by measuring the air flow resistance using the dynamic moisture permeation cell (DMPC) at different humidity conditions. The DMPC measurements show that the polyelectrolyte multilayer closures provide significantly large resistance to air flow, approximately 20-800 times larger than that possible with conventional hook and loop type closure systems, at all humidity levels (from 5 to 95% relative humidity). Hence, from the point of view of providing a hermetic seal against toxic gas permeation, the polyelectrolyte multilayer closures are viable candidates for further engineering development. However, the adhesive strength of the multilayer closures measured by atomic force microscopy suggests that the magnitude of adhesion is much smaller than what is possible with mechanical closures. Therefore, we envisage the development of a composite closure system combining the mechanical closure to provide strong adhesion and the multilayer closure to provide hermetic sealing. © 2012 American Chemical Society
Feasibility of lane closures using probe data : technical brief.
DOT National Transportation Integrated Search
2017-04-01
This study developed an on-line system analysis tool called the Work Zone Interactive : Management Application - Planning (WIMAP-P), an easy-to-use and easy-to-learn tool for : predicting the traffic impact caused by work zone lane closures on freewa...
The transport and behaviour of isoproturon in unsaturated chalk cores
NASA Astrophysics Data System (ADS)
Besien, T. J.; Williams, R. J.; Johnson, A. C.
2000-04-01
A batch sorption study, a microcosm degradation study, and two separate column leaching studies were used to investigate the transport and fate of isoproturon in unsaturated chalk. The column leaching studies used undisturbed core material obtained from the field by dry percussion drilling. Each column leaching study used 25 cm long, 10 cm wide unsaturated chalk cores through which a pulse of isoproturon and bromide was eluted. The cores were set-up to simulate conditions in the unsaturated zone of the UK Chalk aquifer by applying a suction of 1 kPa (0.1 m H 2O) to the base of each column, and eluting at a rate corresponding to an average recharge rate through the unsaturated Chalk. A dye tracer indicated that the flow was through the matrix under these conditions. The results from the first column study showed high recovery rates for both isoproturon (73-92%) and bromide (93-96%), and that isoproturon was retarded by a factor of about 1.23 relative to bromide. In the second column study, two of the four columns were eluted with non-sterile groundwater in place of the sterile groundwater used on all other columns, and this study showed high recovery rates for bromide (85-92%) and lower recovery rates for isoproturon (66-79% — sterile groundwater, 48-61% — non-sterile groundwater). The enhanced degradation in the columns eluted with non-sterile groundwater indicated that groundwater microorganisms had increased the degradation rate within these columns. Overall, the reduced isoproturon recovery in the second column study was attributed to increased microbial degradation as a result of the longer study duration (162 vs. 105 days). The breakthrough curves (BTCs) for bromide had a characteristic convection-dispersion shape and were accurately simulated with the minimum of calibration using a simple convection-dispersion model (LEACHP). However, the isoproturon BTCs had an unusual shape and could not be accurately simulated.
32 CFR 989.25 - Base closure and realignment.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 32 National Defense 6 2013-07-01 2013-07-01 false Base closure and realignment. 989.25 Section 989... PROTECTION ENVIRONMENTAL IMPACT ANALYSIS PROCESS (EIAP) § 989.25 Base closure and realignment. Base closure or realignment may entail special requirements for environmental analysis. The permanent base closure...
32 CFR 989.25 - Base closure and realignment.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 32 National Defense 6 2012-07-01 2012-07-01 false Base closure and realignment. 989.25 Section 989... PROTECTION ENVIRONMENTAL IMPACT ANALYSIS PROCESS (EIAP) § 989.25 Base closure and realignment. Base closure or realignment may entail special requirements for environmental analysis. The permanent base closure...
Gonçalves, Antonio José; de Souza, J A L; Menezes, M B; Kavabata, N K; Suehara, A B; Lehn, C N
2009-11-01
The extension of the surgery and closure type of the pharynx can be the determinants in the pharyngocutaneous fistula development. The objective of the study is to evaluate the incidence of pharingocutaneous salivary fistulae after total laryngectomies comparing manual and mechanical sutures. The study is designed as non-randomized, prospective clinical study. Sixty patients with squamous cell carcinoma were submitted to total laryngectomies. In 30 cases, the linear stapler (75 mm) closure (surgical technique described in details) and in other 30 cases manual suture was used. The cases of mechanical suture were prospective and consecutive and the cases of manual suture were a review series of patients who underwent a manual suture of pharynx, in the same period of time. The statistical analysis between the two groups concluded that both were comparable. Fistulae incidence was 6.7% (2/30) in the group with the mechanical suture and 36.7% (11/30) in the group with manual suture closure, presenting a significant difference (p = 0.0047). The total laryngectomy with mechanical closure is an easy and fast learning technique, allowing watertight closure of the pharynx with a low risk of contamination of the surgical field. It is an assured method, even in previously irradiated patients, since we respect the limits of its indication regarding the extension of primary tumor that must be confirmed by previous suspension laryngectomy performed in the operating room.
El-Mashad, Abd El-Rahman; El-Mahdy, Heba; El Amrousy, Doaa; Elgendy, Marwa
2017-02-01
In this prospective study, we compared the efficacy and side effects of indomethacin, ibuprofen, and paracetamol in patent ductus arteriosus (PDA) closure in preterm neonates. Three hundred preterm neonates with hemodynamically significant PDA (hs-PDA) admitted at our neonatal intensive care unit were enrolled in the study. They were randomized into three groups. Group I (paracetamol group) received 15 mg/kg/6 h IV paracetamol infusion for 3 days. Group II (ibuprofen group) received 10 mg/kg IV ibuprofen infusion followed by 5 mg/kg/day for 2 days. Group III (indomethacin group) received 0.2 mg/kg/12 h indomethacin IV infusion for three doses. Laboratory investigations such as renal function test, liver function test, complete blood count, and blood gases were conducted in addition to echocardiographic examinations. All investigations were done before and 3 days after treatment. There was no significant difference between all groups regarding efficacy of PDA closure (P = 0.868). There was a significant increase in serum creatinine levels and serum blood urea nitrogen (BUN) in the ibuprofen and indomethacin groups (P < 0.001). There was a significant reduction in platelet count and urine output (UOP) in both ibuprofen and indomethacin groups (P < 0.001). There was a significant increase in bilirubin levels in only the ibuprofen group (P = 0.003). No significant difference of hemoglobin (HB) level or liver enzymes in all groups (P > 0.05). Ventilatory settings improved significantly in patients with successful closure of PDA than those with failed PDA closure (P < 0.001). Paracetamol is as effective as indomethacin and ibuprofen in closure of PDA in preterm neonates and has less side effects mainly on renal function, platelet count, and GIT bleeding. What is Known: • Hemodynamically significant patent ductus arteriosus has many complications for preterm and low birth weight neonates and better to be closed. Many drugs were used for medical closure of PDA e.g. indomethacin, ibuprofen and recently paracetamol. Many studies compare safety and efficacy of paracetamol with either indomethacin or ibuprofen. What is New: • It is the first large study that compares the efficacy and side effects of the three drugs in one study.
Sungur, Metin; Karakurt, Cemsit; Ozbarlas, Nazan; Baspinar, Osman
2013-08-01
To evaluate safety and efficacy of closure of patent ductus arteriosus (PDA) with Amplatzer duct occluder II Additional Sizes (ADO II AS) and to report early and midterm results of the device in children and very young symptomatic infants. Retrospective analysis of angiographic data of 60 children from four pediatric cardiology centers. The median patient age and weight were 6.5 (0.5-168) months and 6.8 (1.19-57) kg, respectively. In the study, 26 children had a body weight of ≤ 6 kg. Of these 26 children, 9 had a body weight of ≤ 3 kg. The median narrowest diameter of PDA was 2 (1.2-4) mm. Ductal anatomy was Type A in 29, Type B in 2, Type C in 11, Type D in 1, and Type E in 16 patients, and a residual PDA after surgery in 1 patient. Closure with ADO II AS was achieved in 58 (96.6%) of 60 attempted cases. In two infants, the device was not released because of significant residual shunt. ADO II was used in one, and the other was sent to surgery. Complete closure was observed in all ADO II AS deployed children by the next day on echocardiography. Median follow-up was 12 (1-18) months. Neither death nor any major complications occurred. Our study shows that closure of medium and small sized PDA by using ADO II AS device is effective and safe in children. The use of the device will expand the field of application of PDA closure in small infants. © 2013 Wiley Periodicals, Inc.
Strain-energy release rate analysis of a laminate with a postbuckled delamination
NASA Technical Reports Server (NTRS)
Whitcomb, John D.; Shivakumar, K. N.
1987-01-01
The objectives are to present the derivation of the new virtual crack closure technique, evaluate the accuracy of the technique, and finally to present the results of a limited parametric study of laminates with a postbuckled delamination. Although the new virtual crack closure technique is general, only homogeneous, isotropic laminates were analyzed. This was to eliminate the variation of flexural stiffness with orientation, which occurs even for quasi-isotropic laminates. This made it easier to identify the effect of geometrical parameters on G. The new virtual crack closure technique is derived. Then the specimen configurations are described. Next, the stress analyses is discussed. Finally, the virtual crack closure technique is evaluated and then used to calculate the distribution of G along the delamination front of several laminates with a postbuckled delamination.
Pearson, Tim; Campbell, Michael J; Maheswaran, Ravi
2016-08-01
Acute noise exposure may acutely increase blood pressure but the hypothesis that acute exposure to aircraft noise may trigger cardiovascular events has not been investigated. This study took advantage of a six-day closure of a major airport in April 2010 caused by volcanic ash to examine if there was a decrease in emergency cardiovascular hospital admissions during or immediately after the closure period, using an interrupted daily time-series study design. The population living within the 55dB(A) noise contour was substantial at 0.7 million. The average daily admission count was 13.9 (SD 4.4). After adjustment for covariates, there was no evidence of a decreased risk of hospital admission from cardiovascular disease during the closure period (relative risk 0.97 (95% CI 0.75-1.26)). Using lags of 1-7 days gave similar results. Further studies are needed to investigate if transient aircraft noise exposure can trigger acute cardiovascular events. Copyright © 2016. Published by Elsevier Ltd.
Murakami, Yohko; Wang, Dandan; Burkemper, Bruce; Lin, Shan C.; Varma, Rohit
2016-01-01
Purpose To compare grading of goniophotographic images and gonioscopy in assessing the iridocorneal angle. Methods In a population-based, cross-sectional study, participants underwent gonioscopy and goniophotographic imaging during the same visit. The iridocorneal angle was classified as closed if the posterior trabecular meshwork could not be seen. A single masked observer graded the goniophotographic images, and each eye was classified as having angle closure based on the number of closed quadrants. Agreement between the methods was analyzed by calculating kappa (κ) and first-order agreement coefficient (AC1) statistics and comparison of area under receiver operating characteristic curves (AUC). Results A total of 4149 Chinese Americans (3994 eyes) were included in this study. The agreement for angle closure diagnosis between gonioscopy and EyeCam was moderate to excellent (κ = 0.60, AC1 0.90, AUC 0.76–0.80). Conclusions Detection of iridocorneal angle closure based on goniophotographic imaging shows moderate to very good agreement with angle closure assessment using gonioscopy. PMID:27571018
Protopine alkaloids in horse urine.
Wynne, Paul M; Vine, John H; Amiet, R Gary
2004-11-05
Protopine was extracted from Fumaria officinalis and purified by column chromatography. Urine samples were collected from horses and a human volunteer that had been administered either F. officinalis or protopine free base. Plant and urine samples were acetylated and analysed by GCMS after solid-phase extraction (SPE). The urinary metabolites of protopine were identified as 4,6,7,13-tetrahydro-9,10-dihydroxy-5-methyl-benzo[e]-l,3-benzodioxolo [4,5-1][2] benzazecin-12(5H)-one, 4,6,7,13-tetrahydro-10-hydroxy-9-methoxy-5-methyl-benzo[e]-1,3-benzodioxolo[4,5-1][2] benzazecin-12(5H)-one and 4,6,7,13-tetrahydro-9-hydroxy-10-methoxy-5-methyl-benzo[e]-1,3-benzodioxolo[4,5-l][2] benzazecin-12(5H)-one, chelianthifoline, isochelianthifoline and 2-O-desmethylchelianthifoline. The metabolic formation of the tetrahydroprotoberberines by closure of the bridge across N5 and C13 is rate limited and protopine-like metabolites accumulate only when the route is overloaded. Metabolism was qualitatively similar in the horse and human.
Control of aperture closure during reach-to-grasp movements in parkinson’s disease
Rand, M. K.; Smiley-Oyen, A. L.; Shimansky, Y. P.; Bloedel, J. R.; Stelmach, G. E.
2007-01-01
This study examined whether the pattern of coordination between arm-reaching toward an object (hand transport) and the initiation of aperture closure for grasping is different between PD patients and healthy individuals, and whether that pattern is affected by the necessity to quickly adjust the reach-to-grasp movement in response to an unexpected shift of target location. Subjects reached for and grasped a vertical dowel, the location of which was indicated by illuminating one of the three dowels placed on a horizontal plane. In control conditions, target location was fixed during the trial. In perturbation conditions, target location was shifted instantaneously by switching the illumination to a different dowel during the reach. The hand distance from the target at which the subject initiated aperture closure (aperture closure distance) was similar for both the control and perturbation conditions within each group of subjects. However, that distance was significantly closer to the target in the PD group than in the control group. The timing of aperture closure initiation varied considerably across the trials in both groups of subjects. In contrast, aperture closure distance was relatively invariant, suggesting that aperture closure initiation was determined by spatial parameters of arm kinematics rather than temporal parameters. The linear regression analysis of aperture closure distance showed that the distance was highly predictable based on the following three parameters: the amplitude of maximum grip aperture, hand velocity, and hand acceleration. This result implies that a control law, the arguments of which include the above parameters, governs the initiation of aperture closure. Further analysis revealed that the control law was very similar between the subject groups under each condition as well as between the control and perturbation conditions for each group. Consequently, the shorter aperture closure distance observed in PD patients apparently is a result of the hypometria of their grip aperture and bradykinesia of hand transport movement, rather than a consequence of a deficit in transport-grasp coordination. It is also concluded that the perturbation of target location does not disrupt the transport-grasp coordination in either healthy individuals or PD patients. PMID:16307233
Control of aperture closure during reach-to-grasp movements in Parkinson's disease.
Rand, M K; Smiley-Oyen, A L; Shimansky, Y P; Bloedel, J R; Stelmach, G E
2006-01-01
This study examined whether the pattern of coordination between arm-reaching toward an object (hand transport) and the initiation of aperture closure for grasping is different between PD patients and healthy individuals, and whether that pattern is affected by the necessity to quickly adjust the reach-to-grasp movement in response to an unexpected shift of target location. Subjects reached for and grasped a vertical dowel, the location of which was indicated by illuminating one of the three dowels placed on a horizontal plane. In control conditions, target location was fixed during the trial. In perturbation conditions, target location was shifted instantaneously by switching the illumination to a different dowel during the reach. The hand distance from the target at which the subject initiated aperture closure (aperture closure distance) was similar for both the control and perturbation conditions within each group of subjects. However, that distance was significantly closer to the target in the PD group than in the control group. The timing of aperture closure initiation varied considerably across the trials in both groups of subjects. In contrast, aperture closure distance was relatively invariant, suggesting that aperture closure initiation was determined by spatial parameters of arm kinematics rather than temporal parameters. The linear regression analysis of aperture closure distance showed that the distance was highly predictable based on the following three parameters: the amplitude of maximum grip aperture, hand velocity, and hand acceleration. This result implies that a control law, the arguments of which include the above parameters, governs the initiation of aperture closure. Further analysis revealed that the control law was very similar between the subject groups under each condition as well as between the control and perturbation conditions for each group. Consequently, the shorter aperture closure distance observed in PD patients apparently is a result of the hypometria of their grip aperture and bradykinesia of hand transport movement, rather than a consequence of a deficit in transport-grasp coordination. It is also concluded that the perturbation of target location does not disrupt the transport-grasp coordination in either healthy individuals or PD patients.
Dynamic modelling of costs and health consequences of school closure during an influenza pandemic
2012-01-01
Background The purpose of this article is to evaluate the cost-effectiveness of school closure during a potential influenza pandemic and to examine the trade-off between costs and health benefits for school closure involving different target groups and different closure durations. Methods We developed two models: a dynamic disease model capturing the spread of influenza and an economic model capturing the costs and benefits of school closure. Decisions were based on quality-adjusted life years gained using incremental cost-effectiveness ratios. The disease model is an age-structured SEIR compartmental model based on the population of Oslo. We studied the costs and benefits of school closure by varying the age targets (kindergarten, primary school, secondary school) and closure durations (1–10 weeks), given pandemics with basic reproductive number of 1.5, 2.0 or 2.5. Results The cost-effectiveness of school closure varies depending on the target group, duration and whether indirect costs are considered. Using a case fatality rate (CFR) of 0.1-0.2% and with current cost-effectiveness threshold for Norway, closing secondary school is the only cost-effective strategy, when indirect costs are included. The most cost-effective strategies would be closing secondary schools for 8 weeks if R0=1.5, 6 weeks if R0=2.0, and 4 weeks if R0= 2.5. For severe pandemics with case fatality rates of 1-2%, similar to the Spanish flu, or when indirect costs are disregarded, the optimal strategy is closing kindergarten, primary and secondary school for extended periods of time. For a pandemic with 2009 H1N1 characteristics (mild severity and low transmissibility), closing schools would not be cost-effective, regardless of the age target of school children. Conclusions School closure has moderate impact on the epidemic’s scope, but the resulting disruption to society imposes a potentially great cost in terms of lost productivity from parents’ work absenteeism. PMID:23140513
Vetter, Diana; Raptis, Dimitri Aristotle; Giama, Mira; Hosa, Hanna; Muller, Markus K; Nocito, Antonio; Schiesser, Marc; Moos, Rudolf; Bueter, Marco
2017-12-01
The aims of the present study were to assess whether planned secondary wound closure at the insertion site of the circular stapler reduces wound infection rate and postoperative morbidity after laparoscopic Roux-en-Y gastric bypass (RYGB) and to identify independent predictive factors increasing the risk for wound infections after RYGB. This paper is a retrospective single-center analysis of a prospectively collected database of 1400 patients undergoing RYGB surgery in circular technique between June 2000 and June 2016. Planned secondary wound closure at the circular stapler introduction site was performed at postoperative day 3 in 291 (20.8%) consecutive patients and compared to a historical control of 1109 (79.2%) consecutive patients with primary wound closure. Independent predictive factors for wound infection were assessed by multivariable analysis. Secondary wound closure significantly decreased wound infection rate from 9.3% (103/1109) to 1% (3/291) (p < 0.001) leading to a shorter hospital stay (mean 9 (SD8) vs. 7 days (SD2), p < 0.001), lower costs (p = 0.039), and reduced postoperative morbidity (mean 90-day Comprehensive Complication Index (CCI) 7.4 (SD14.0) vs. 5.1 (SD11.1) p = 0.008) when compared to primary wound closure. Primary wound closure, dyslipidemia, and preoperative gastritis were independent predictive risk factors for developing wound infections both in the univariate (p < 0.001; p = 0.048; p = 0.003) and multivariable analysis (p < 0.001; p = 0.040; p = 0.012). Further, on multivariable analysis, the female gender was a predictive factor (p = 0.034) for wound infection development. Secondary wound closure at the circular stapler introduction site in laparoscopic RYGB significantly reduces the overall wound infection rate as well as postoperative morbidity, costs, and hospital stay when compared to primary wound closure.
Abdelaziz, Hesham K; Saad, Marwan; Abuomara, Hossamaldin Z; Nairooz, Ramez; Pothineni, Naga Venkata K; Madmani, Mohamed E; Roberts, David H; Mahmud, Ehtisham
2018-05-04
To examine long-term clinical outcomes with transcatheter patent foramen ovale (PFO) closure versus medical therapy alone in patients with cryptogenic stroke. A long-standing debate regarding the optimal approach for the management of patients with PFO after a cryptogenic stroke exists. An electronic search was performed for randomized clinical trials (RCTs) reporting clinical outcomes with PFO closure vs. medical therapy alone after stroke. Random effects DerSimonian-Laird risk ratios (RR) were calculated. The main outcome was recurrence of stroke. Other outcomes included transient ischemic attack (TIA), new-onset atrial fibrillation/flutter (AF/AFL), major bleeding, serious adverse events, and device-related complications. All-cause mortality was also examined. Five RCTs with a total of 3,440 patients were included. At a mean follow-up of 4.02 ± 1.57 years, PFO closure was associated with less recurrence of stroke (RR = 0.43; 95% CI 0.19-0.91; P = .027) compared with medical therapy alone. No difference was observed between both strategies for TIA (P = .21), major bleeding (P = .69), serious adverse events (P = .35), and all-cause death (P = .48). However, PFO closure, was associated with increased new-onset AF/AFL (P < .001), risk of pulmonary embolism (P = .04), and device-related complications (P < .001). On a subgroup analysis, stroke recurrence rate remained lower in PFO closure arm regardless of the type of closure device used (P interaction = .50), or the presence of substantial shunt in the majority of study population (P interaction = .13). Transcatheter PFO closure reduces the recurrence of stroke compared with medical therapy alone, with no significant safety concerns. Close follow-up of patients after PFO closure is recommended to detect new-onset atrial arrhythmias. © 2018 Wiley Periodicals, Inc.
Eerola, Anneli; Jokinen, Eero; Boldt, Talvikki; Pihkala, Jaana
2006-03-07
We aimed to evaluate the effect of percutaneous closure of patent ductus arteriosus (PDA) on left ventricular (LV) hemodynamics. Today, most PDAs are closed percutaneously. Little is known, however, about hemodynamic changes after the procedure. Of 37 children (ages 0.6 to 10.6 years) taken to the catheterization laboratory for percutaneous PDA closure, the PDA was closed in 33. Left ventricular diastolic and systolic dimensions, volumes, and function were examined by two-dimensional (2D) and three-dimensional (3D) echocardiography and serum concentrations of natriuretic peptides measured before PDA closure, on the following day, and 6 months thereafter. Control subjects comprised 36 healthy children of comparable ages. At baseline, LV diastolic diameter measured >+2 SD in 5 of 33 patients. In 3D echocardiography, a median LV diastolic volume measured 54.0 ml/m2 in the control subjects and 58.4 ml/m2 (p < 0.05) in the PDA group before closure and 57.2 ml/m2 (p = NS) 6 months after closure. A median N-terminal brain natriuretic peptide (pro-BNP) concentration measured 72 ng/l in the control group and 141 ng/l in the PDA group before closure (p = 0.001) and 78.5 ng/l (p = NS) 6 months after closure. Patients differed from control subjects in indices of LV systolic and diastolic function at baseline. By the end of follow-up, all these differences had disappeared. Even in the subgroup of patients with normal-sized LV at baseline, the LV diastolic volume decreased significantly during follow-up. Changes in LV volume and function caused by PDA disappear by 6 months after percutaneous closure. Even the children with normal-sized LV benefit from the procedure.
Nolan, Winifred P; See, Jovina L; Chew, Paul T K; Friedman, David S; Smith, Scott D; Radhakrishnan, Sunita; Zheng, Ce; Foster, Paul J; Aung, Tin
2007-01-01
To evaluate noncontact anterior segment optical coherence technology (AS-OCT) as a qualitative method of imaging the anterior chamber angle and to determine its ability to detect primary angle closure when compared with gonioscopy in Asian subjects. Prospective observational case series. Two hundred three subjects were recruited from glaucoma clinics in Singapore with diagnoses of primary angle closure, primary open-angle glaucoma, ocular hypertension, or cataract. Both eyes (if eligible) of each patient were included in the study. Exclusion criteria were pseudophakia or previous glaucoma surgery. Images of the nasal, temporal, and inferior angles were obtained with AS-OCT in dark and then light conditions. Gonioscopic angle width was graded using the Spaeth classification for each quadrant in low lighting conditions. Angle closure was defined by AS-OCT as contact between the peripheral iris and angle wall anterior to the scleral spur and by gonioscopy as a Spaeth grade of 0 degree (posterior trabecular meshwork not visible). Comparison of the 2 methods in detecting angle closure was done by eye and by individual. Sensitivities and specificities of AS-OCT were calculated using gonioscopy as the reference standard. Complete data were available for 342 eyes of 200 patients. Of the patients, 70.9% had a clinical diagnosis of treated or untreated primary angle closure. Angle closure in > or =1 quadrants was detected by AS-OCT in 142 (71%) patients (228 [66.7%] eyes) and by gonioscopy in 99 (49.5%) patients (152 [44.4%] eyes). The inferior angle was closed more frequently than the nasal or temporal quadrants using both AS-OCT and gonioscopy. When performed under dark conditions, AS-OCT identified 98% of those subjects found to have angle closure on gonioscopy (95% confidence interval [CI], 92.2-99.6) and led to the characterization of 44.6% of those found to have open angles on gonioscopy to have angle closure as well. With gonioscopy as the reference standard, specificity of AS-OCT in the dark was 55.4% (95% CI, 45.2-65.2) for detecting individuals with angle closure. Anterior segment OCT is a rapid noncontact method of imaging angle structures. It is highly sensitive in detecting angle closure when compared with gonioscopy. More persons are found to have closed angles with AS-OCT than with gonioscopy.
Van den Branden, Ben J; Post, Martijn C; Plokker, Herbert W; ten Berg, Jurriën M; Suttorp, Maarten J
2010-09-01
The aim of this study was to assess the mid-term safety and efficacy of percutaneous patent foramen ovale (PFO) closure using a bioabsorbable device (BioSTAR, NMT Medical, Boston, Massachusetts). Closure of PFO in patients with cryptogenic stroke has proven to be safe and effective using different types of permanent devices. All consecutive patients who underwent percutaneous PFO closure with the bioabsorbable closure device between November 2007 and January 2009 were included. Residual shunt was assessed using contrast transthoracic echocardiography. Sixty-two patients (55% women, mean age 47.7 ± 11.8 years) underwent PFO closure. The in-hospital complications were a surgical device retrieval in 2 patients (3.2%), device reposition in 1 (1.6%), and a minimal groin hematoma in 6 patients (9.7%). The short-term complications at 1-month follow-up (n = 60) were a transient ischemic attack in the presence of a residual shunt in 1 patient and new supraventricular tachycardia in 7 patients (11.3%). At 6-month follow-up (n = 60), 1 patient without residual shunt developed a transient ischemic attack and 1 developed atrial fibrillation. A mild or moderate residual shunt was noted in 51.7%, 33.9%, and 23.7% after 1-day, 1-month, and 6-month follow-up, respectively. A large shunt was present in 8.3%, 3.4%, and 0% after 1-day, 1-month, and 6-month follow-up. Closure of PFO using the bioabsorbable device is associated with a low complication rate and a low recurrence rate of embolic events. However, a relatively high percentage of mild or moderate residual shunting is still present at 6-month follow-up. Copyright © 2010 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
Tissue loads applied by a novel medical device for closing large wounds.
Katzengold, Rona; Topaz, Moris; Gefen, Amit
2016-02-01
Closure of large soft tissue defects following surgery or trauma as well as closure of large chronic wounds constitutes substantial but common reconstructive challenges. In such cases, an attempt to use conventional suturing will result in high-tension closure, therefore alternative external skin stretching systems were developed. These types of devices were meant to reduce local mechanical loads in the skin and the underlying tissues, taking advantage of the viscoelastic properties of the skin, especially mechanical creep, for primary wound closure. Studies have shown the clinical advantages of skin stretching systems, however, quantitative bioengineering models, demonstrating closure of large wounds, are lacking. Here we present finite element (FE) modeling of the TopClosure(®) tension relief system (TRS) and its biomechanical efficacy in three (real) wound cases, compared with the alternative of a conventional surgical suturing closure technique. Our simulations showed that peak effective stresses on the skin were at least an order of magnitude greater (and sometimes nearly 2 orders-of-magnitude greater) when tension sutures were used with respect to the corresponding TRS data. For the tension suture simulations, the tensile stress was in the range of 415-648 MPa and in the TRS simulations, it was 16-30 MPa. Based on the present computational FE modeling, the TRS reduces localized tissue deformations and stress concentrations in skin and underlying tissues while closing large wounds, compared to the deformations and stresses that are inflicted during the process of suturing. This substantial reduction of loads allows surgeons to better employ the viscoelastic properties of the skin for primary wound closure. Copyright © 2015 Tissue Viability Society. Published by Elsevier Ltd. All rights reserved.
Tay, Elton Lik Tong; Yong, Vernon Khet Yau; Lim, Boon Ang; Sia, Stelson; Wong, Elizabeth Poh Ying; Yip, Leonard Wei Leon
2015-01-01
To determine angle closure agreements between gonioscopy and anterior segment optical coherence tomography (AS-OCT), as well as gonioscopy and spectral domain OCT (SD-OCT). A secondary objective was to quantify inter-observer agreements of AS-OCT and SD-OCT assessments. Seventeen consecutive subjects (33 eyes) were recruited from the study hospital's Glaucoma clinic. Gonioscopy was performed by a glaucomatologist masked to OCT results. OCT images were read independently by 2 other glaucomatologists masked to gonioscopy findings as well as each other's analyses of OCT images. Totally 84.8% and 45.5% of scleral spurs were visualized in AS-OCT and SD-OCT images respectively (P<0.01). The agreement for angle closure between AS-OCT and gonioscopy was fair at k=0.31 (95% confidence interval, CI: 0.03-0.59) and k=0.35 (95% CI: 0.07-0.63) for reader 1 and 2 respectively. The agreement for angle closure between SD-OCT and gonioscopy was fair at k=0.21 (95% CI: 0.07-0.49) and slight at k=0.17 (95% CI: 0.08-0.42) for reader 1 and 2 respectively. The inter-reader agreement for angle closure in AS-OCT images was moderate at 0.51 (95% CI: 0.13-0.88). The inter-reader agreement for angle closure in SD-OCT images was slight at 0.18 (95% CI: 0.08-0.45). Significant proportion of scleral spurs were not visualised with SD-OCT imaging resulting in weaker inter-reader agreements. Identifying other angle landmarks in SD-OCT images will allow more consistent angle closure assessments. Gonioscopy and OCT imaging do not always agree in angle closure assessments but have their own advantages, and should be used together and not exclusively.
Automated analysis of angle closure from anterior chamber angle images.
Baskaran, Mani; Cheng, Jun; Perera, Shamira A; Tun, Tin A; Liu, Jiang; Aung, Tin
2014-10-21
To evaluate a novel software capable of automatically grading angle closure on EyeCam angle images in comparison with manual grading of images, with gonioscopy as the reference standard. In this hospital-based, prospective study, subjects underwent gonioscopy by a single observer, and EyeCam imaging by a different operator. The anterior chamber angle in a quadrant was classified as closed if the posterior trabecular meshwork could not be seen. An eye was classified as having angle closure if there were two or more quadrants of closure. Automated grading of the angle images was performed using customized software. Agreement between the methods was ascertained by κ statistic and comparison of area under receiver operating characteristic curves (AUC). One hundred forty subjects (140 eyes) were included, most of whom were Chinese (102/140, 72.9%) and women (72/140, 51.5%). Angle closure was detected in 61 eyes (43.6%) with gonioscopy in comparison with 59 eyes (42.1%, P = 0.73) using manual grading, and 67 eyes (47.9%, P = 0.24) with automated grading of EyeCam images. The agreement for angle closure diagnosis between gonioscopy and both manual (κ = 0.88; 95% confidence interval [CI), 0.81-0.96) and automated grading of EyeCam images was good (κ = 0.74; 95% CI, 0.63-0.85). The AUC for detecting eyes with gonioscopic angle closure was comparable for manual and automated grading (AUC 0.974 vs. 0.954, P = 0.31) of EyeCam images. Customized software for automated grading of EyeCam angle images was found to have good agreement with gonioscopy. Human observation of the EyeCam images may still be needed to avoid gross misclassification, especially in eyes with extensive angle closure. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.
Baruteau, Alban-Elouen; Lambert, Virginie; Riou, Jean-Yves; Angel, Claude-Yves; Belli, Emre; Petit, Jérôme
2015-01-01
Closure of tubular patent ductus arteriosus remains a challenging procedure. Anecdotal use of Amplatzer Vascular Plug IV for tubular ductus closure has been reported but feasibility and safety in a consecutive patients' series remain unknown. We performed a monocenter prospective study at the Marie Lannelongue Hospital in Paris, France. From 2009 to 2014, a total of 47 patients (39 infants, 3 children, and 5 adults) underwent ductus closure with the Plug IV. Ductus morphology was a type E in 34 (72.3%) patients and a type C in 13 (27.7%) patients. Ductus closure occurred in 39 (83.0%) infants at a median age of seven months (range: 3-23 months) and a median weight of 6.9 kg (range: 4.1-17.0 kg). A past history of prematurity and very low birth weight was found in 33 (70.2%) of them. Twelve (25.5%) patients had pulmonary hypertension. Mean Plug IV diameter was 1.9 ± 0.1 mm larger than the mean maximal ductus diameter. Early complete closure of the ductus was obtained in all patients. Early migration of an undersized Plug IV occurred in one (2.1%) patient and was suitable for percutaneous device retrieval. After a mean follow-up of 3.4 ± 1.4 years, all patients are alive and asymptomatic, no late complication occurred. Transcatheter closure of tubular ductus with the Amplatzer Vascular Plug IV can be safe and effective, with a 100% early occlusion rate. This device, suitable for a 4F sheath, is a new alternative for tubular ductus closure in low-body-weight infants. © The Author(s) 2014.
Bentham, James; English, Kate; Hares, Dominic; Gibbs, John; Thomson, John
2012-10-01
The aim of this study was to describe the clinical importance and methods of transcatheter closure of systemic venous baffle leaks after atrial redirection procedures for transposed great vessels. Until the late 1970s, atrial redirection surgery was the principal surgical palliative approach to manage transposed great vessels. Baffle leaks are among the many long-term complications of this type of surgery, and their prevalence increases over time. The clinical consequences of baffle leaks in this population are poorly understood, and the indications for closure are incompletely defined. During outpatient follow-up of 126 patients after atrial redirection surgery, 15 baffle leaks were detected in 11 patients. All underwent transcatheter closure using either an occluding device or a covered stent if there was concomitant baffle obstruction. The average age at the time of the procedure was 26 years (range 6 to 42). Ten of 11 patients were cyanosed at rest or on a simple walk test (median oxygen saturation level 80%, range 65% to 96%). Six of 11 patients were polycythemic before leak closure (median hemoglobin concentration 19 g/dl, range 13.8 to 23). After closure, there was a significant improvement in saturation (median 97%, p <0.0001) and a significant reduction in hemoglobin concentration at 6 months after the procedure (median 14.8 g/dl, p <0.05). There were no procedural adverse events. One patient experienced late device embolization necessitating surgical removal. In conclusion, transcatheter closure of baffle leaks is a technically feasible although frequently complex and lengthy procedure. Closure is associated with an improvement in oxygen saturations and a reduction in polycythaemia. Copyright © 2012 Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Willoughby III, O.H.; Lukes, G.C.
EnergySolutions, LLC operates its Mixed Waste Facility at Clive, Utah under the provisions of its State-issued Part B Permit. The facility accepts waste that contains both hazardous and radioactive contaminants. Utah is an EPA Agreement State and therefore the Utah Division of Solid and Hazardous Waste (DSHW) is authorized to regulate the hazardous waste operations at the facility. The radioactive portion of the waste is regulated by the Utah Division of Radiation Control. 40 CFR 264.142 outlines the facility requirements for Closure Costs. The owner or operator must have a detailed written estimate of the cost of closing the facilitymore » in accordance with the rules. For many years the State of Utah had relied on the facility's estimate of closure costs as the amount that needed to be funded. This amount is reviewed annually and adjusted for inflation and for changes at the facility. In 2004 the agency and the facility requested bids from independent contractors to provide their estimate for closure costs. Three engineering firms bid on the project. The facility funded the project and both the agency and the facility chose one of the firms to provide an independent estimate. The engineering firms met with both parties and toured the facility. They were also provided with the current closure cost line items. Each firm provided an estimated cost for closure of the facility at the point in the facility's active life that would make the closure most expensive. Included with the direct costs were indirect line items such as overhead, profit, mobilization, hazardous working conditions and regulatory oversight. The agency and the facility reviewed the independent estimates and negotiated a final Closure and Post-Closure Cost Estimate for the Mixed Waste Facility. There are several mechanisms allowed under the rules to fund the Closure and Post- Closure Care Funds. EnergySolutions has chosen to fund their costs through the use of an insurance policy. Changing mechanisms from an irrevocable trust to an insurance policy required extensive review by the DSHW and the Utah Attorney General's Office. The duration of the Post-Closure Care Period is generally designated as 30 years under the hazardous waste rules. The Legislature of the State of Utah commissioned a review of the need for Perpetual Care Funds for hazardous waste facilities. This fund would provide funds for maintenance and monitoring of facilities following termination of the Post-Closure Permit. The DSHW has recommended to the legislature that a perpetual care fund be created. The legislature will study the recommendation and take appropriate action. (authors)« less
Patent Foramen Ovale Closure or Antiplatelet Therapy for Cryptogenic Stroke.
Søndergaard, Lars; Kasner, Scott E; Rhodes, John F; Andersen, Grethe; Iversen, Helle K; Nielsen-Kudsk, Jens E; Settergren, Magnus; Sjöstrand, Christina; Roine, Risto O; Hildick-Smith, David; Spence, J David; Thomassen, Lars
2017-09-14
The efficacy of closure of a patent foramen ovale (PFO) in the prevention of recurrent stroke after cryptogenic stroke is uncertain. We investigated the effect of PFO closure combined with antiplatelet therapy versus antiplatelet therapy alone on the risks of recurrent stroke and new brain infarctions. In this multinational trial involving patients with a PFO who had had a cryptogenic stroke, we randomly assigned patients, in a 2:1 ratio, to undergo PFO closure plus antiplatelet therapy (PFO closure group) or to receive antiplatelet therapy alone (antiplatelet-only group). Imaging of the brain was performed at the baseline screening and at 24 months. The coprimary end points were freedom from clinical evidence of ischemic stroke (reported here as the percentage of patients who had a recurrence of stroke) through at least 24 months after randomization and the 24-month incidence of new brain infarction, which was a composite of clinical ischemic stroke or silent brain infarction detected on imaging. We enrolled 664 patients (mean age, 45.2 years), of whom 81% had moderate or large interatrial shunts. During a median follow-up of 3.2 years, clinical ischemic stroke occurred in 6 of 441 patients (1.4%) in the PFO closure group and in 12 of 223 patients (5.4%) in the antiplatelet-only group (hazard ratio, 0.23; 95% confidence interval [CI], 0.09 to 0.62; P=0.002). The incidence of new brain infarctions was significantly lower in the PFO closure group than in the antiplatelet-only group (22 patients [5.7%] vs. 20 patients [11.3%]; relative risk, 0.51; 95% CI, 0.29 to 0.91; P=0.04), but the incidence of silent brain infarction did not differ significantly between the study groups (P=0.97). Serious adverse events occurred in 23.1% of the patients in the PFO closure group and in 27.8% of the patients in the antiplatelet-only group (P=0.22). Serious device-related adverse events occurred in 6 patients (1.4%) in the PFO closure group, and atrial fibrillation occurred in 29 patients (6.6%) after PFO closure. Among patients with a PFO who had had a cryptogenic stroke, the risk of subsequent ischemic stroke was lower among those assigned to PFO closure combined with antiplatelet therapy than among those assigned to antiplatelet therapy alone; however, PFO closure was associated with higher rates of device complications and atrial fibrillation. (Funded by W.L. Gore and Associates; Gore REDUCE ClinicalTrials.gov number, NCT00738894 .).
Low cracking concretes for the closure pours and overlays of the Dunlap Creek Bridge : final report.
DOT National Transportation Integrated Search
2017-10-01
Joints, wide cracks, and poor-quality concretes facilitate the intrusion of chlorides, causing corrosion in bridge decks and substructures. In this study, joints were replaced with closure pours (link slabs) consisting of low permeability fiber-reinf...
2014-01-01
Background Laparoscopic appendectomy (LA) has become one of the most common surgical procedures to date. To improve and standardize this technique further, cost-effective and reliable animal models are needed. Methods In a pilot study, 30 Wistar rats underwent laparoscopic caecum resection (as rats do not have an appendix vermiformis), to optimize the instrumental and surgical parameters. A subsequent test study was performed in another 30 rats to compare three different techniques for caecum resection and bowel closure. Results Bipolar coagulation led to an insufficiency of caecal stump closure in all operated rats (Group 1, n = 10). Endoloop ligation followed by bipolar coagulation and resection (Group 2, n = 10) or resection with a LigaSure™ device (Group 3, n = 10) resulted in sufficient caecal stump closure. Conclusions We developed a LA model enabling us to compare three different caecum resection techniques in rats. In conclusion, only endoloop closure followed by bipolar coagulation proved to be a secure and cost-effective surgical approach. PMID:24934381
Ludwig, C; Behrend, M; Hoffarth, U; Schüttler, W; Stoelben, E
2004-09-01
This study was aimed to determine the resistance to pressure of manual and stapled bronchial closures under ideal conditions (90 degrees to the bronchial tree) and parallel to the trachea (45 degrees). An experimental study was done on 60 explanted pig tracheae which were alternatively closed with either double-layer, running sutures angled 90 degrees to the cartilaginous rings or an automatic stapling device. The closure line was placed exactly 90 degrees to the bronchial tree in 30 cases and parallel to the trachea (45 degrees) in 30. The sutures were placed under pressure until air leakage was observed. The leakage pressure was digitally recorded. A statistically significant difference existed between the two groups. Mechanical sutures proved more resistant to pressure (P=0.011). Under ideal conditions, the resistance to pressure of mechanical sutures is equal to if not better than that of manual sutures.
Jiang, Hai-bin; Bai, Yuan; Zong, Gang-jun; Han, Lin; Li, Wei-ping; Lu, Yang; Qin, Yong-wen; Zhao, Xian-xian
2013-01-01
The aim of this study was to evaluate a new type of occluder for patent ductus arteriosus. Patent ductus arteriosus was established in a canine model by anastomosing a length of autologous jugular vein to the descending aorta and the left pulmonary artery in an end-to-side fashion. Transcatheter closure of each patent ductus arteriosus was performed on 10 dogs, which were then monitored for as long as 6 months with aortography, echocardiography, and histologic evaluation. Transcatheter closure with use of the novel pan-nitinol device was successful in all canine models. Postoperative echocardiography showed that the location and shape of the occluders were normal, without any residual shunting. Further histologic evaluation confirmed that the occluder surface was completely endothelialized 3 months after implantation. Transcatheter patent ductus arteriosus closure with the pan-nitinol occluder can be performed safely and successfully in a canine model and shows good biological compatibility and low mortality rates.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bostick, D.T.; DePaoli, S.M.; Lucero, A.J.
1999-10-18
A gamma counting system has been assembled that can profile the breakthrough fronts of gamma-emitting radioisotopes longitudinally and axially along a loaded column. This profiling technique has been particularly useful in columns studies such as those performed with IONSP IE-911, a crystalline silicotitanate (CST) manufactured by UOP, in which unusually long operating times are required to observe cesium breakthrough in column effluent. The length of the mass transfer zone and extent of column saturation can be detected early in a column study by viewing the relative emission of gamma emitters along I the length of the column. In this study,more » gamma scans were used to analyze loaded CST and zeolite columns used in the treatment of process wastewater simulant and actual groundwater. Results indicate good run-to-run reproductibility in acquiring the scans. The longitudinal gamma scans for both {sup 90}Sr and {sup 137}Cs conformed with breakthrough results reported on the basis of column effluent activity. Although not obvious from data obtained by monitoring effluent activity, the gamma scans indicated that both cesium and strontium in the saturated zone of the CST column are slowly displaced by the higher levels of groundwater cations and are then resorbed further down the column. This displacement phenomenon identified by gamma scans was verified using data from a zeolite column, in which both the gamma scan and column effluent data exhibited radionuclide displacement by groundwater cations. The gamma emission intensities from the CST column runs are used to quantitate and compare the distribution coefficient and loading capacity of {sup 137}Cs on CST versus zeolite.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
NSTec Environmental Restoration
CAU 127, Areas 25 and 26 Storage Tanks, consists of twelve CASs located in Areas 25 and 26 of the NTS. The closure alternatives included no further action, clean closure, and closure in place with administrative controls. The purpose of this Closure Report is to provide a summary of the completed closure activities, documentation of waste disposal, and analytical data to confirm that the remediation goals were met.
Transapical access closure: the TA PLUG device†
Brinks, Henriette; Nietlispach, Fabian; Göber, Volkhard; Englberger, Lars; Wenaweser, Peter; Meier, Bernhard; Carrel, Thierry; Huber, Christoph
2013-01-01
OBJECTIVES Percutaneous closure of the transapical (TA) access site for large-calibre devices is an unsolved issue. We report the first experimental data on the TA PLUG device for true-percutaneous closure following large apical access for transcatheter aortic valve implantation. METHODS The TA PLUG, a self-sealing full-core closure device, was implanted in an acute animal study in six pigs (60.2 ± 0.7 kg). All the pigs received 100 IU/kg of heparin. The targeted activated clotting time was left to normalize spontaneously. After accessing the left ventricular apex with a 39 French introducer, the closure plug device was delivered with a 33 French over-the-wire system under fluoroscopic guidance into the apex. Time to full haemostasis as well as rate of bleeding was recorded. Self-anchoring properties were assessed by haemodynamic push stress under adrenalin challenge. An additional feasibility study was conducted in four pigs (58.4 ± 1.1 kg) with full surgical exposure of the apex, and assessed device anchoring by pull-force measurements with 0.5 Newton (N) increments. All the animals were electively sacrified. Post-mortem analysis of the heart was performed and the renal embolic index assessed. RESULTS Of six apical closure devices, five were correctly inserted and fully deployed at the first attempt. One became blocked in the delivery system and was placed successfully at the second attempt. In all the animals, complete haemostasis was immediate and no leak was recorded during the 5-h observation period. Neither leak nor any device dislodgement was observed under haemodynamic push stress with repeated left ventricular peak pressure of up to 220 mmHg. In the feasibility study assessing pull-stressing, device migration occurred at a force of 3.3 ± 0.5 N corresponding to 247.5 mmHg. Post-mortem analyses confirmed full expansion of all devices at the intended target. No macroscopic damage was identified at the surrounding myocardium. The renal embolic index was zero. CONCLUSIONS True-percutaneous left ventricular apex closure following large access is feasible with the self-sealing TA PLUG. The device allows for immediate haemostasis and a reliable anchoring in the acute animal setting. This is the first report of a true-percutaneous closure for large-calibre transcatheter aortic valve implantation access. PMID:23842759
40 CFR 265.1202 - Closure and post-closure care.
Code of Federal Regulations, 2010 CFR
2010-07-01
... post-closure care. (a) At closure of a magazine or unit which stored hazardous waste under this subpart... estimates for closure, and financial responsibility for magazines or units must meet all of the requirements... as long as it remains in service as a munitions or explosives magazine or storage unit. (b) If, after...
Visvanathan, Vikranth; Vallamkondu, Vamsidhar; Bhimrao, Sanjiv K
2018-06-01
Objectives Surgical repair of a tympanic membrane perforation is a common otologic procedure. However, achieving a successful closure can be challenging, especially if the anterior margin of the tympanic membrane is involved. The aim of this study was to systematically review the literature on evidence published in closure of anterior tympanic membrane perforations. Data Sources The following data sources were searched: Cochrane Central Register of Controlled Trials (1997 to August, 3 2017), MEDLINE (February 1948 to August 3, 2017), and Embase (1975 to August 3, 2017). Data Extraction Two authors independently reviewed titles and abstracts. The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines were followed. For the purpose of this study, the inclusion criteria were as follows; (1) studies reporting surgical technique for closure of anterior tympanic membrane perforations, (2) primary cases only, (3) articles published in the English language, (4) minimum 6-month follow-up, and (5) recorded pre- and postoperative audiometry. The exclusion criteria were non-English language articles, revision surgery, and no audiometric outcomes. Results On initial search, a total of 181 articles were identified (PubMed, n = 136; Cochrane, n = 28; Embase, n = 17). Based on the criteria, 136 articles were excluded. Full text of 45 articles was reviewed, and a further 24 articles were excluded. A total of 21 articles fulfilled the criteria for study inclusion. Conclusions All published evidence is level 4. High-quality controlled studies are required to determine the most effective method for closure of anterior tympanic membrane perforation.
AMPLATZER versus Figulla occluder for transcatheter patent foramen ovale closure.
Trabattoni, Daniela; Gaspardone, Achille; Sgueglia, Gregory A; Fabbiocchi, Franco; Gioffrè, Gaetano; Montorsi, Piero; Calligaris, Giuseppe; Iamele, Maria; De Santis, Antonella; Bartorelli, Antonio L
2017-04-20
The aim of this observational study was to compare acute and 12-month results of percutaneous closure of patent foramen ovale (PFO) with two occluder devices. Between June 2007 and October 2014, 406 consecutive patients (48.1±13.3 years, 243 women) underwent percutaneous PFO closure with either the AMPLATZER (n=179) or the Figulla (n=227) device after a stroke or a transient ischaemic attack ascribed to the PFO. A right-to-left shunt grade >1 was previously detected in all patients and atrial septal aneurysm was present in 111 (27.5%) patients. Patients were followed up with a contrast transthoracic echocardiogram and clinically at 24 hours, six months, and 12 months after the procedure. A high procedural success was observed in both groups. Despite a trend towards a higher incidence of acute residual shunt immediately after device deployment among Figulla occluder patients, a residual grade ≥2 right-to-left shunt was observed in 4.5% of patients, independently of the device used for PFO closure. The only difference reported after Figulla device implantation was a lower rate of supraventricular arrhythmias (9% vs. 17%, p=0.02). According to this two-centre study, PFO closure appears safe and effective with the Figulla occluder as well as with the AMPLATZER device.
Kijima, Yasufumi; Akagi, Teiji; Nakagawa, Koji; Taniguchi, Manabu; Ueoka, Akira; Deguchi, Kentaro; Toh, Norihisa; Oe, Hiroki; Kusano, Kengo; Sano, Shunji; Ito, Hiroshi
2014-01-01
Although numerous studies have shown an association between a patent foramen ovale (PFO) and cryptogenic cerebrovascular accidents (CVA), there has been no definitive control study that demonstrated the benefit of percutaneous device closure of a PFO compared to medical therapy in patients with CVA. Additionally, few clinical data exist for Japanese patients in this field. We demonstrate the initial experiences in catheter closure of a PFO as secondary prevention of CVA in Japan. Catheter closure of a PFO was attempted in 7 patients who were diagnosed with cryptogenic CVA. Mean age at the procedure was 54 ± 19 years. The presence of spontaneous interatrial right-to-left shunts was demonstrated by transesophageal contrast echocardiography without Valsalva maneuver in all of the patients. Amplatzer Cribriform device (n = 4) or Amplatzer PFO Occluder (n = 3) was used for the procedure and was successfully deployed. Device-related complications were not observed at the time of the procedure or during the follow-up period (mean period of 16 ± 9 months). Catheter closure of a PFO could be safely performed with Amplatzer Cribriform or Amplatzer PFO Occluder. This procedure may contribute to prevention of recurrent cryptogenic CVA in Japanese patients.
NASA Astrophysics Data System (ADS)
Anderson, Dallas W.; Hsu, Tung M.; Halpern, Steven J.; Honaker, Arnold
1993-07-01
The ProClosureTM System (PCS) consists of a low power 1.32micrometers Nd:YAG laser coupled to a handheld disposable fiber optic device. The system has been designed to perform a wide range of tissue welding applications such as cosmetic skin closure,vascular surgery, and minimally invasive surgical procedures normally performed with sutures and staples. Utilizing a wavelength for tissue fusion that is least distracted by medium in the surgical field coupled with a computerized delivery system allows for a more precise application (+/- 5%) of laser energy to the tissue. The study design involved the micro-surgical anastomosis of twenty Sprague-Dawley rats (vas deferens) and twenty-one Sprague-Dawley rats (femoral arteries). Each rat is its own contralateral control. Laser repair time is approximately one-third that of conventional suturing. Postoperative dissection and burst strength testing was conducted at day 0, 1, 7, and 14. At each postoperative interval, the mean leak/burst strength for laser-assisted closure v. control, was markedly higher. The precise application of energy fluence resulting from ProClosure's computerized system yields an initial strength and a fluid static seal that is superior to conventional suture closure.
Closure of population biobanks and direct-to-consumer genetic testing companies.
Zawati, Ma'n H; Borry, Pascal; Howard, Heidi Carmen
2011-09-01
Genetic research gained new momentum with the completion of the Human Genome Project in 2003. Formerly centered on the investigation of single-gene disorders, genetic research is increasingly targeting common complex diseases and in doing so is studying the whole genome, the environment and its impact on genomic variation. Consequently, biobanking initiatives have emerged around the world as a tool to sustain such progress. Whether they are small scale or longitudinal, public or private, commercial or non-commercial, biobanks should consider the possibility of closure. Interestingly, while raising important ethical issues, this topic has hardly been explored in the literature. Indeed, ethical issues associated with sale, insolvency, end of funding, or transfer of materials to other entities (which are all issues either related to or possible consequences of closure) are seldom the subject of discussion. In an attempt to fill this gap, this paper will discuss-using population and direct-to-consumer (DTC) genetic testing companies' biobanks as case studies-(1) international and national normative documents addressing the issue of closure and (2) the internal policies of population biobanks and DTC genetic testing companies. The analysis will inform the debate on biobank closure and elucidate the underlying ethical issues, which include, but are not limited to informed consent, storage and privacy.
Loading properties of porous layered capillary columns with sorbents of different natures
NASA Astrophysics Data System (ADS)
Patrushev, Y. V.; Nikolaeva, O. A.; Sidelnikov, V. N.
2017-04-01
Loading properties are studied for the commercial porous layered capillary columns GASPRO, Rt-Q-BOND, and for columns with porous layers based on the divinylbenzene-vinylimidazole copolymer (DVB-VIm), poly(trimethylsilyl)propyn (PTMSP) and ordered silica of the MCM-41 type. It is shown that the loading capacity of a column based on MCM-41 is 5-10 times higher than in the other considered columns. The loading properties of porous layered columns and columns for gas-liquid chromatography are compared.
ERIC Educational Resources Information Center
Drange, Ida
2016-01-01
This article compares outcomes in the Norwegian labour market for non-Western immigrants and majority colleagues with professional or master's degrees within three different fields of study: health science, social science and natural science. Professions have a higher degree of occupational closure, which may entail that non-Western immigrants…
A clinical investigation of force delivery systems for orthodontic space closure.
Nightingale, C; Jones, S P
2003-09-01
To investigate the force retention, and rates of space closure achieved by elastomeric chain and nickel titanium coil springs. Randomized clinical trial. Eastman Dental Hospital, London and Queen Mary's University Hospital, Roehampton, 1998-2000. Twenty-two orthodontic patients, wearing the pre-adjusted edgewise appliance undergoing space closure in opposing quadrants, using sliding mechanics on 0.019 x 0.025-inch posted stainless steel archwires. Medium-spaced elastomeric chain [Durachain, OrthoCare (UK) Ltd., Bradford, UK] and 9-mm nickel titanium coil springs [OrthoCare (UK) Ltd.] were placed in opposing quadrants for 15 patients. Elastomeric chain only was used in a further seven patients. The initial forces on placement and residual forces at the subsequent visit were measured with a dial push-pull gauge [Orthocare (UK) Ltd]. Study models of eight patients were taken before and after space closure, from which measurements were made to establish mean space closure. The forces were measured in grammes and space closure in millimetres. Fifty-nine per cent (31/53) of the elastomeric sample maintained at least 50 per cent of the initial force over a time period of 1-15 weeks. No sample lost all its force, and the mean loss was 47 per cent (range: 0-76 per cent). Nickel titanium coil springs lost force rapidly over 6 weeks, following that force levels plateaued. Forty-six per cent (12/26) maintained at least 50 per cent of their initial force over a time period of 1-22 weeks, and mean force loss was 48 per cent (range: 12-68 per cent). The rate of mean weekly space closure for elastomeric chain was 0.21 mm and for nickel titanium coil springs 0.26 mm. There was no relationship between the initial force applied and rate of space closure. None of the sample failed during the study period giving a 100 per cent response rate. In clinical use, the force retention of elastomeric chain was better than previously concluded. High initial forces resulted in high force decay. Nickel titanium coil springs and elastomeric chain closed spaces at a similar rate.
Boyd, Matt; Baker, Michael G.; Mansoor, Osman D.; Kvizhinadze, Giorgi; Wilson, Nick
2017-01-01
Background Countries are well advised to prepare for future pandemic risks (e.g., pandemic influenza, novel emerging agents or synthetic bioweapons). These preparations do not typically include planning for complete border closure. Even though border closure may not be instituted in time, and can fail, there might still plausible chances of success for well organized island nations. Objective To estimate costs and benefits of complete border closure in response to new pandemic threats, at an initial proof-of-concept level. New Zealand was used as a case-study for an island country. Methods An Excel spreadsheet model was developed to estimate costs and benefits. Case-study specific epidemiological data was sourced from past influenza pandemics. Country-specific healthcare cost data, valuation of life, and lost tourism revenue were imputed (with lost trade also in scenario analyses). Results For a new pandemic equivalent to the 1918 influenza pandemic (albeit with half the mortality rate, “Scenario A”), it was estimated that successful border closure for 26 weeks provided a net societal benefit (e.g., of NZ$11.0 billion, USD$7.3 billion). Even in the face of a complete end to trade, a net benefit was estimated for scenarios where the mortality rate was high (e.g., at 10 times the mortality impact of “Scenario A”, or 2.75% of the country’s population dying) giving a net benefit of NZ$54 billion (USD$36 billion). But for some other pandemic scenarios where trade ceased, border closure resulted in a net negative societal value (e.g., for “Scenario A” times three for 26 weeks of border closure–but not for only 12 weeks of closure when it would still be beneficial). Conclusions This “proof-of-concept” work indicates that more detailed cost-benefit analysis of border closure in very severe pandemic situations for some island nations is probably warranted, as this course of action might sometimes be worthwhile from a societal perspective. PMID:28622344
2011-01-01
Background Colorectal cancer is the second most common tumor in developed countries, with a lifetime prevalence of 5%. About one third of these tumors are located in the rectum. Surgery in terms of low anterior resection with mesorectal excision is the central element in the treatment of rectal cancer being the only option for definite cure. Creating a protective diverting stoma prevents complications like anastomotic failure and meanwhile is the standard procedure. Bowel obstruction is one of the main and the clinically and economically most relevant complication following closure of loop ileostomy. The best surgical technique for closure of loop ileostomy has not been defined yet. Methods/Design A study protocol was developed on the basis of the only randomized controlled mono-center trial to solve clinical equipoise concerning the optimal surgical technique for closure of loop ileostomy after low anterior resection due to rectal cancer. The HASTA trial is a multi-center pragmatic randomized controlled surgical trial with two parallel groups to compare hand-suture versus stapling for closure of loop ileostomy. It will include 334 randomized patients undergoing closure of loop ileostomy after low anterior resection with protective ileostomy due to rectal cancer in approximately 20 centers consisting of German hospitals of all level of health care. The primary endpoint is the rate of bowel obstruction within 30 days after ileostomy closure. In addition, a set of surgical and general variables including quality of life will be analyzed with a follow-up of 12 months. An investigators meeting with a practical session will help to minimize performance bias and enforce protocol adherence. Centers are monitored centrally as well as on-site before and during recruitment phase to assure inclusion, treatment and follow up according to the protocol. Discussion Aim of the HASTA trial is to evaluate the efficacy of hand-suture versus stapling for closure of loop ileostomy in patients with rectal cancer. Trial registration German Clinical Trial Register Number: DRKS00000040 PMID:21303515
Raspovic, Katherine M; Wukich, Dane K; Naiman, Daniel Q; Lavery, Lawrence A; Kirsner, Robert S; Kim, Paul J; Steinberg, John S; Attinger, Christopher E; Danilkovitch, Alla
2018-04-23
In a multicenter randomized controlled trial (RCT), the use of viable cryopreserved placental membrane (vCPM) for chronic diabetic foot ulcers (DFUs) resulted in a higher proportion of wound closure in comparison to good wound care: 62% vs. 21% (p < 0.01). However, patients in RCTs are not representative of daily physician practice. Healthcare databases serve as a valuable tool to evaluate therapy effectiveness and to supplement evidence from RCTs. The objective of this study was to evaluate the effectiveness of vCPM for DFU management using Net Health's WoundExpert ® electronic health records (EHR). The primary endpoint was the proportion of DFUs that achieved complete closure. Other endpoints included time and number of grafts to closure, probability of wound closure by week 12, and the number of wound-related infections and amputations. De-identified EHR data for 360 patients with 441 wounds treated with vCPM were extracted from the database. Average patient age was 63.7 years with a mean wound size of 5.1 cm 2 and an average wound duration of 102 days prior to vCPM treatment. For evaluation of clinical outcomes, 350 DFUs larger than 0.25 cm 2 at baseline were analyzed. Closure at the end of treatment was achieved in 59.4% of wounds with a median treatment duration of 42.0 days and 4 applications of vCPM. The probability of wound closure at week 12 was 71%, and the number of amputations and wound-related infections was 13 (3.0%) and 9 (2.0%), respectively. Data also demonstrated a correlation between wound size and closure rate as well as a correlation between > 50% wound area reduction by week 4 and wound closure by week 12. The results of this study mirror previous RCT efficacy data, supporting the benefits of vCPM for DFU management. These results can also influence policy and treatment decisions regarding advanced vCPM technology. This article is protected by copyright. All rights reserved. © 2018 by the Wound Healing Society.
Phase closure nulling: Theory and practice
NASA Astrophysics Data System (ADS)
Chelli, A.; Duvert, G.; Malbet, F.; Kern, P.
2009-11-01
We provide a complete theory of the phase closure of a binary system in which a small, feeble, and unresolved companion acts as a perturbing parameter on the spatial frequency spectrum of a dominant, bright, resolved source. We demonstrate that the influence of the companion can be measured with precision by measuring the phase closure of the system near the nulls of the primary visibility function. In these regions of phase closure nulling, frequency intervals always exist where the phase closure signature of the companion is larger than any systematic error and can thus be measured. We show that this technique allows retrieval of many astrophysically relevant properties of faint and close companions such as flux, position, and in favorable cases, spectrum. As a proof of concept, using the AMBER/VLTI instrument with 3 auxiliary telescopes of 1.8 m and only 15 minutes of on-sky integration, we detected the five magnitudes fainter companion of HD 59717 at only 3.5 stellar radii distance from the primary. This is one of the highest contrast detected by interferometry between a companion and its parent star. We conclude by a rapid study of the potentialities of phase closure nulling observations with current interferometers and explore the requirements for a new type of dedicated instrument.
DOE Office of Scientific and Technical Information (OSTI.GOV)
BECHTEL NEVADA
2006-09-01
This Closure Report (CR) describes the closure activities performed at CAU 528, Polychlorinated Biphenyls Contamination, as presented in the Nevada Division of Environmental Protection (NDEP)-approved Corrective Action Plan (CAP) (US. Department of Energy, National Nuclear Security Administration Nevada Site Office [NNSAINSO], 2005). The approved closure alternative was closure in place with administrative controls. This CR provides a summary of the completed closure activities, documentation of waste disposal, and analytical data to confirm that the remediation goals were met.
A Political Analysis of Community Influence over School Closure
ERIC Educational Resources Information Center
Finnigan, Kara S.; Lavner, Mark
2012-01-01
This study seeks to understand community member participation in and influence over an urban school district's school closure process. Data from interviews with School Board members, district administrators, and community members, as well as district documents and newspaper articles suggest that district administrators limited participation…
Steel-reinforced concrete-filled steel tubular columns under axial and lateral cyclic loading
NASA Astrophysics Data System (ADS)
Farajpourbonab, Ebrahim; Kute, Sunil Y.; Inamdar, Vilas M.
2018-03-01
SRCFT columns are formed by inserting a steel section into a concrete-filled steel tube. These types of columns are named steel-reinforced concrete-filled steel tubular (SRCFT) columns. The current study aims at investigating the various types of reinforcing steel section to improve the strength and hysteresis behavior of SRCFT columns under axial and lateral cyclic loading. To attain this objective, a numerical study has been conducted on a series of composite columns. First, FEM procedure has been verified by the use of available experimental studies. Next, eight composite columns having different types of cross sections were analyzed. For comparison purpose, the base model was a CFT column used as a benchmark specimen. Nevertheless, the other specimens were SRCFT types. The results indicate that reinforcement of a CFT column through this method leads to enhancement in load-carrying capacity, enhancement in lateral drift ratio, ductility, preventing of local buckling in steel shell, and enhancement in energy absorption capacity. Under cyclic displacement history, it was observed that the use of cross-shaped reinforcing steel section causes a higher level of energy dissipation and the moment of inertia of the reinforcing steel sections was found to be the most significant parameter affecting the hysteresis behavior of SRCFT columns.
Umbilical hernia following gastroschisis closure: a common event?
Tullie, L G C; Bough, G M; Shalaby, A; Kiely, E M; Curry, J I; Pierro, A; De Coppi, P; Cross, K M K
2016-08-01
To assess incidence and natural history of umbilical hernia following sutured and sutureless gastroschisis closure. With audit approval, we undertook a retrospective clinical record review of all gastroschisis closures in our institution (2007-2013). Patient demographics, gastroschisis closure method and umbilical hernia occurrence were recorded. Data, presented as median (range), underwent appropriate statistical analysis. Fifty-three patients were identified, gestation 36 weeks (31-38), birth weight 2.39 kg (1-3.52) and 23 (43 %) were male. Fourteen patients (26 %) underwent sutureless closure: 12 primary, 2 staged; and 39 (74 %) sutured closure: 19 primary, 20 staged. Sutured closure was interrupted sutures in 24 patients, 11 pursestring and 4 not specified. Fifty patients were followed-up over 53 months (10-101) and 22 (44 %) developed umbilical hernias. There was a significantly greater hernia incidence following sutureless closure (p = 0.0002). In sutured closure, pursestring technique had the highest hernia rate (64 %). Seven patients underwent operative hernia closure; three secondary to another procedure. Seven patients had their hernias resolve. One patient was lost to follow-up and seven remain under observation with no reported complications. There is a significant umbilical hernia incidence following sutureless and pursestring sutured gastroschisis closure. This has not led to complications and the majority have not undergone repair.
Li, Ming-Hsu; Wang, Tsing-Hai; Teng, Shi-Ping
2009-02-15
This study investigated breakthrough curves (BTCs) from a series of column experiments, including different column lengths and flow rates, of a conservative tracer, tritium oxide (HTO), and a radionuclide, cesium, in crushed granite using a reactive transport model. Results of the short column, with length of 2cm, showed an underestimation of the retardation factor and the corresponding HTO BTCs cannot be successfully modeled even with overestimated fluid dispersivity. Column supporting elements, including filters and rings, on both ends of packed granite were shown to be able to induce additional dispersive mixing, thus significantly affecting BTCs of short columns while those of the long column, with length of 8cm, were less affected. By increasing flow rates from 1mL/min to 5mL/min, the contribution of structural dispersive mixing to the false tilting of short column BTCs still cannot be detached. To reduce the influence of structural dispersivity on BTCs, the equivalent pore volume of column supporting materials should be much smaller than that of packed porous medium. The total length of column supporting structures should be greatly shorter than that of porous medium column.
Plenis, Alina; Rekowska, Natalia; Bączek, Tomasz
2016-01-01
This article focuses on correlating the column classification obtained from the method created at the Katholieke Universiteit Leuven (KUL), with the chromatographic resolution attained in biomedical separation. In the KUL system, each column is described with four parameters, which enables estimation of the FKUL value characterising similarity of those parameters to the selected reference stationary phase. Thus, a ranking list based on the FKUL value can be calculated for the chosen reference column, then correlated with the results of the column performance test. In this study, the column performance test was based on analysis of moclobemide and its two metabolites in human plasma by liquid chromatography (LC), using 18 columns. The comparative study was performed using traditional correlation of the FKUL values with the retention parameters of the analytes describing the column performance test. In order to deepen the comparative assessment of both data sets, factor analysis (FA) was also used. The obtained results indicated that the stationary phase classes, closely related according to the KUL method, yielded comparable separation for the target substances. Therefore, the column ranking system based on the FKUL-values could be considered supportive in the choice of the appropriate column for biomedical analysis. PMID:26805819
Plenis, Alina; Rekowska, Natalia; Bączek, Tomasz
2016-01-21
This article focuses on correlating the column classification obtained from the method created at the Katholieke Universiteit Leuven (KUL), with the chromatographic resolution attained in biomedical separation. In the KUL system, each column is described with four parameters, which enables estimation of the FKUL value characterising similarity of those parameters to the selected reference stationary phase. Thus, a ranking list based on the FKUL value can be calculated for the chosen reference column, then correlated with the results of the column performance test. In this study, the column performance test was based on analysis of moclobemide and its two metabolites in human plasma by liquid chromatography (LC), using 18 columns. The comparative study was performed using traditional correlation of the FKUL values with the retention parameters of the analytes describing the column performance test. In order to deepen the comparative assessment of both data sets, factor analysis (FA) was also used. The obtained results indicated that the stationary phase classes, closely related according to the KUL method, yielded comparable separation for the target substances. Therefore, the column ranking system based on the FKUL-values could be considered supportive in the choice of the appropriate column for biomedical analysis.
A computer analysis of reflex eyelid motion in normal subjects and in facial neuropathy.
Somia, N N; Rash, G S; Epstein, E E; Wachowiak, M; Sundine, M J; Stremel, R W; Barker, J H; Gossman, D
2000-12-01
To demonstrate how computerized eyelid motion analysis can quantify the human reflex blink. Seventeen normal subjects and 10 patients with unilateral facial nerve paralysis were analyzed. Eyelid closure is currently evaluated by systems primarily designed to assess lower/midfacial movements. The methods are subjective, difficult to reproduce, and measure only volitional closure. Reflex closure is responsible for eye hydration, and its evaluation demands dynamic analysis. A 60Hz video camera incorporated into a helmet was used to analyze blinking. Reflective markers on the forehead and eyelids allowed for the dynamic measurement of the reflex blink. Eyelid displacement, velocity and acceleration were calculated. The degree of synchrony between bilateral blinks was also determined. This study demonstrates that video motion analysis can describe normal and altered eyelid motions in a quantifiable manner. To our knowledge, this is the first study to measure dynamic reflex blinks. Eyelid closure may now be evaluated in kinematic terms. This technique could increase understanding of eyelid motion and permit more accurate evaluation of eyelid function. Dynamic eyelid evaluation has immediate applications in the treatment of facial palsy affecting the reflex blink. Relevance No method has been developed that objectively quantifies dynamic eyelid closure. Methods currently in use evaluate only volitional eyelid closure, and are based on direct and indirect observer assessments. These methods are subjective and are incapable of analyzing dynamic eyelid movements, which are critical to maintenance of corneal hydration and comfort. A system that quantifies eyelid kinematics can provide a functional analysis of blink disorders and an objective evaluation of their treatment(s).
27 CFR 26.136 - Affixing closures.
Code of Federal Regulations, 2012 CFR
2012-04-01
... OF THE TREASURY LIQUORS LIQUORS AND ARTICLES FROM PUERTO RICO AND THE VIRGIN ISLANDS Closures for Distilled Spirits From Puerto Rico § 26.136 Affixing closures. Closures or other devices shall be securely...
27 CFR 26.136 - Affixing closures.
Code of Federal Regulations, 2013 CFR
2013-04-01
... OF THE TREASURY ALCOHOL LIQUORS AND ARTICLES FROM PUERTO RICO AND THE VIRGIN ISLANDS Closures for Distilled Spirits From Puerto Rico § 26.136 Affixing closures. Closures or other devices shall be securely...
27 CFR 26.136 - Affixing closures.
Code of Federal Regulations, 2010 CFR
2010-04-01
... OF THE TREASURY LIQUORS LIQUORS AND ARTICLES FROM PUERTO RICO AND THE VIRGIN ISLANDS Closures for Distilled Spirits From Puerto Rico § 26.136 Affixing closures. Closures or other devices shall be securely...
27 CFR 26.136 - Affixing closures.
Code of Federal Regulations, 2014 CFR
2014-04-01
... OF THE TREASURY ALCOHOL LIQUORS AND ARTICLES FROM PUERTO RICO AND THE VIRGIN ISLANDS Closures for Distilled Spirits From Puerto Rico § 26.136 Affixing closures. Closures or other devices shall be securely...
27 CFR 26.136 - Affixing closures.
Code of Federal Regulations, 2011 CFR
2011-04-01
... OF THE TREASURY LIQUORS LIQUORS AND ARTICLES FROM PUERTO RICO AND THE VIRGIN ISLANDS Closures for Distilled Spirits From Puerto Rico § 26.136 Affixing closures. Closures or other devices shall be securely...
Rodríguez Sánchez de la Blanca, Ana; Sánchez Luna, M; González Pacheco, N; Arriaga Redondo, M; Navarro Patiño, N
2018-02-01
Closure of a patent ductus arteriosus (PDA) in preterm infants modifies cardiac output and induces adaptive changes in the hemodynamic situation. The present study aims to analyze those changes, through a non-invasive cardiac output monitor based on blood electrical velocimetry, in preterm babies. A prospective observational study of preterm infants with a gestational age of less than 28 weeks, and a hemodynamic significant PDA, requires intravenous ibuprofen or surgical closure. All patients were monitored with electrical velocimetry before treatment and through the following 72 h. Two groups were defined, ibuprofen and surgical closure. Variations of cardiac output were analyzed from the basal situation and at 1, 8, 24, 48, and 72 h on each group. During a 12-month period, 18 patients were studied. The median gestational age in the ibuprofen group (12/18) was 26 +5 weeks (25 +5 -27 +3 ) with a median birth weight of 875 (670-1010) g. The cardiac output index (CI) value was 0.29 l/kg/min (0.24-0.34). Among the patients with confirmed ductus closure (50%), a significant CI decrease was shown (0.24 vs 0.29 l/kg/min; P 0.03) after 72 h (three ibuprofen doses). A statistically significant decrease in systolic volume (SVI) was found: 1.62 vs 1.88 ml/kg, P 0.03 with a decrease in contractility (ICON), 85 vs 140, P 0.02. The gestational age in the surgical group (6/18) was 25 +2 weeks (24-26 +3 ) with a median weight of 745 (660-820) g. All patients in this group showed a decrease in the immediate postoperative CI (1 h after surgery) 0.24 vs 0.30 l/kg/min, P 0.05, and a significant decrease in contractility (ICON 77 vs 147, P 0.03). In addition, a no statistically significant decrease in SVI (1.54 vs 1.83 ml/kg, P 0.06), as well as an increase in systemic vascular resistance (10,615 vs 8797 dyn/cm 2 , P 0.08), were detected. This deterioration was transient without significant differences in the remaining periods of time evaluated. The surgical closure of the PDA in preterm infants causes a transient deterioration of cardiac function linked to a documented decrease in the left ventricular output. The hemodynamic changes detected after pharmacological PDA closure are similar but those patients present a better clinical tolerance to changes in the cardiac output. What is Known: • Surgical ductus closure generates acute hemodynamic changes in cardiac output and left ventricular function. What is New: • The hemodynamic changes detected after pharmacological ductus closure are similar to those found in the surgical closure. Electrical velocimetry can detect those changes.
Gao, Wu; Xu, Wenjie; Bian, Xuecheng; Chen, Yunmin
2017-11-01
The settlement of any position of the municipal solid waste (MSW) body during the landfilling process and after its closure has effects on the integrity of the internal structure and storage capacity of the landfill. This paper proposes a practical approach for calculating the settlement and storage capacity of landfills based on the space and time discretization of the landfilling process. The MSW body in the landfill was divided into independent column units, and the filling process of each column unit was determined by a simplified complete landfilling process. The settlement of a position in the landfill was calculated with the compression of each MSW layer in every column unit. Then, the simultaneous settlement of all the column units was integrated to obtain the settlement of the landfill and storage capacity of all the column units; this allowed to obtain the storage capacity of the landfill based on the layer-wise summation method. When the compression of each MSW layer was calculated, the effects of the fluctuation of the main leachate level and variation in the unit weight of the MSW on the overburdened effective stress were taken into consideration by introducing the main leachate level's proportion and the unit weight and buried depth curve. This approach is especially significant for MSW with a high kitchen waste content and landfills in developing countries. The stress-biodegradation compression model was used to calculate the compression of each MSW layer. A software program, Settlement and Storage Capacity Calculation System for Landfills, was developed by integrating the space and time discretization of the landfilling process and the settlement and storage capacity algorithms. The landfilling process of the phase IV of Shanghai Laogang Landfill was simulated using this software. The maximum geometric volume of the landfill error between the calculated and measured values is only 2.02%, and the accumulated filling weight error between the calculated value and measured value is less than 5%. These results show that this approach is practical for satisfactorily and reliably calculating the settlement and storage capacity. In addition, the development of the elevation lines in the landfill sections created with the software demonstrates that the optimization of the design of the structures should be based on the settlement of the landfill. Since this practical approach can reasonably calculate the storage capacity of landfills and efficiently provide the development of the settlement of each landfilling stage, it can be used for the optimizations of landfilling schemes and structural designs. Copyright © 2017 Elsevier Ltd. All rights reserved.
Podda, Mauro; Polignano, Francesco Maria; Luhmann, Andreas; Wilson, Michael Samuel James; Kulli, Christoph; Tait, Iain Stephen
2016-03-01
With advances in laparoscopic instrumentation and acquisition of advanced laparoscopic skills, laparoscopic common bile duct exploration (LCBDE) is technically feasible and increasingly practiced by surgeons worldwide. Traditional practice of suturing the dochotomy with T-tube drainage may be associated with T-tube-related complications. Primary duct closure (PDC) without a T-tube has been proposed as an alternative to T-tube placement (TTD) after LCBDE. The aim of this meta-analysis was to evaluate the safety and effectiveness of PDC when compared to TTD after LCBDE for choledocholithiasis. A systematic literature search was performed using PubMed, EMBASE, MEDLINE, Google Scholar, and the Cochrane Central Register of Controlled Trials databases for studies comparing primary duct closure and T-tube drainage. Studies were reviewed for the primary outcome measures: overall postoperative complications, postoperative biliary-specific complications, re-interventions, and postoperative hospital stay. Secondary outcomes assessed were: operating time, median hospital expenses, and general complications. Sixteen studies comparing PDC and TTD qualified for inclusion in our meta-analysis, with a total of 1770 patients. PDC showed significantly better results when compared to TTD in terms of postoperative biliary peritonitis (OR 0.22, 95% CI 0.06-0.76, P = 0.02), operating time (WMD, -22.27, 95% CI -33.26 to -11.28, P < 0.00001), postoperative hospital stay (WMD, -3.22; 95% CI -4.52 to -1.92, P < 0.00001), and median hospital expenses (SMD, -1.37, 95% CI -1.96 to -0.77, P < 0.00001). Postoperative hospital stay was significantly decreased in the primary duct closure with internal biliary drainage (PDC + BD) group when compared to TTD group (WMD, -2.68; 95% CI -3.23 to -2.13, P < 0.00001). This comprehensive meta-analysis demonstrates that PDC after LCBDE is feasible and associated with fewer complications than TTD. Based on these results, primary duct closure may be considered as the optimal procedure for dochotomy closure after LCBDE.
Regional neural tube closure defined by the Grainy head-like transcription factors.
Rifat, Yeliz; Parekh, Vishwas; Wilanowski, Tomasz; Hislop, Nikki R; Auden, Alana; Ting, Stephen B; Cunningham, John M; Jane, Stephen M
2010-09-15
Primary neurulation in mammals has been defined by distinct anatomical closure sites, at the hindbrain/cervical spine (closure 1), forebrain/midbrain boundary (closure 2), and rostral end of the forebrain (closure 3). Zones of neurulation have also been characterized by morphologic differences in neural fold elevation, with non-neural ectoderm-induced formation of paired dorso-lateral hinge points (DLHP) essential for neural tube closure in the cranial and lower spinal cord regions, and notochord-induced bending at the median hinge point (MHP) sufficient for closure in the upper spinal region. Here we identify a unifying molecular basis for these observations based on the function of the non-neural ectoderm-specific Grainy head-like genes in mice. Using a gene-targeting approach we show that deletion of Grhl2 results in failed closure 3, with mutants exhibiting a split-face malformation and exencephaly, associated with failure of neuro-epithelial folding at the DLHP. Loss of Grhl3 alone defines a distinct lower spinal closure defect, also with defective DLHP formation. The two genes contribute equally to closure 2, where only Grhl gene dosage is limiting. Combined deletion of Grhl2 and Grhl3 induces severe rostral and caudal neural tube defects, but DLHP-independent closure 1 proceeds normally in the upper spinal region. These findings provide a molecular basis for non-neural ectoderm mediated formation of the DLHP that is critical for complete neuraxis closure. (c) 2010 Elsevier Inc. All rights reserved.
Rapid repair of severely damaged reinforced concrete columns.
DOT National Transportation Integrated Search
2012-11-01
Research on rapid repair of reinforced concrete (RC) columns has been limited to columns with slight or moderate damage. Moreover, : few studies have been conducted on repair of severely damaged columns, particularly with buckled or fractured reinfor...
[Perforated peptic ulcer closure: laparoscopic or open?
Alekberzade, A V; Krylov, N N; Rustamov, E A; Badalov, D A; Popovtsev, M A
To compare laparoscopic and open closure of perforated peptic ulcer (PPU). The study included 153 patients who underwent PPU suturing. 78 patients underwent laparoscopic closure (laparoscopic group) and open suturing via upper midline laparotomy was performed in 75 cases (open group). Surgery time, postoperative pain severity, time of analgesics intake, postoperative complications, hospital-stay and and cosmetic effect were compared. Laparoscopic PPU closure may be effective and accessible in experienced endoscopic surgeon. It significantly reduces postoperative pain severity, need for analgesics, incidence of postoperative complications and provides excellent cosmetic effect. However, there is greater time of surgery compared with open intervention. There were no significant differences in hspital-stay between groups. Laparoscopic PPU suturing can be considered a good alternative to open surgery. Further researches are needed for standardization, assessment of safety, real advantages and disadvantages of laparoscopic technique.
On the modelling of non-reactive and reactive turbulent combustor flows
NASA Technical Reports Server (NTRS)
Nikjooy, Mohammad; So, Ronald M. C.
1987-01-01
A study of non-reactive and reactive axisymmetric combustor flows with and without swirl is presented. Closure of the Reynolds equations is achieved by three models: kappa-epsilon, algebraic stress and Reynolds stress closure. Performance of two locally nonequilibrium and one equilibrium algebraic stress models is analyzed assuming four pressure strain models. A comparison is also made of the performance of a high and a low Reynolds number model for combustor flow calculations using Reynolds stress closures. Effects of diffusion and pressure-strain models on these closures are also investigated. Two models for the scalar transport are presented. One employs the second-moment closure which solves the transport equations for the scalar fluxes, while the other solves the algebraic equations for the scalar fluxes. In addition, two cases of non-premixed and one case of premixed combustion are considered. Fast- and finite-rate chemistry models are applied to non-premixed combustion. Both show promise for application in gas turbine combustors. However, finite rate chemistry models need to be examined to establish a suitable coupling of the heat release effects on turbulence field and rate constants.
Mechanisms of Airway Protection during Chin-Down Swallowing
ERIC Educational Resources Information Center
Macrae, Phoebe; Anderson, Cheryl; Humbert, Ianessa
2014-01-01
Purpose: This study examined the effects of chin-down swallowing on laryngeal vestibule closure. It also investigated the technique's rehabilitative impact, by assessing the stability of effects across multiple trials and aftereffects in neutral swallows on cessation of the technique. Method: Duration of laryngeal vestibule closure (dLVC) was…
Helping Disadvantaged Students: Findings from the Thuthuka Programme
ERIC Educational Resources Information Center
Barac, Karin
2015-01-01
Drawing on social closure theory, this study achieved a deep understanding of the perceptions and experiences of the first cohort of candidates passing through the Thuthuka support programme. Using semi-structured interviews as part of a qualitative approach, currently prevalent modes of professional closure were considered by taking the…
DOT National Transportation Integrated Search
1990-06-01
Elber's crack closure model is studied in relation to the results of laboratory spectrum crack growth tests on compact tension specimens (CTS) fabricated from rail effected by mean of an analysis of a center cracked panel (CCP) subjected to an equiva...
Avoiding Accountability: How Charter Operators Evade Ohio's Automatic Closure Law. K-12 Education
ERIC Educational Resources Information Center
DePaoli, Jennifer; van Lier, Piet
2013-01-01
Ohio's charter-closure law is touted as one of the toughest in the nation because it requires the automatic closure of charter schools that consistently fail to meet academic standards. Ohio's charter-closure law, which became effective in 2008 and was revised in 2011, calls for automatic closure of schools rated in Academic Emergency for at least…
Federal Register 2010, 2011, 2012, 2013, 2014
2012-12-19
... Closure, Target Shooting Public Safety Closure on the Lake Mountains in Utah County, UT AGENCY: Bureau of... Lake Mountains in Utah County, Utah, to recreational target shooting to protect public safety. This... shooting closure within the described area will remain in effect no longer than two years from December 19...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-13
... DEPARTMENT OF DEFENSE Department of the Army Record of Decision (ROD) for the Base Closure and... decision on how to implement property disposal in accordance with the Defense Base Closure and Realignment Act of 1990 (the Base Closure Act), Public Law 101-510, as amended, following the closure of Fort...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-05-13
... the forward tip weight retention block (tip block) or aft tip closure (tip closure), loss of the blade...) forward tip weight retention block (tip block) and the aft tip closure (tip closure) for adhesive bond... prevent loss of a tip block or tip closure, loss of a blade, and subsequent loss of control of the...
Ratio-driven resuscitation predicts early fascial closure in the combat wounded.
Glaser, Jacob; Vasquez, Matthew; Cardarelli, Cassandra; Dunne, James; Elster, Eric; Hathaway, Emily; Bograd, Benjamin; Safford, Shawn; Rodriguez, Carlos
2015-10-01
Operation Iraqi Freedom and Operation Enduring Freedom have seen the highest rates of combat casualties since Vietnam. These casualties often require massive transfusion (MT) and immediate surgical attention to control hemorrhage. Clinical practice guidelines dictate ratio-driven resuscitation (RDR) for patients requiring MT. With the transition from crystalloid to blood product resuscitation, we have seen fewer open abdomens in combat casualties. We sought to determine the effect RDR has on achieving early definitive abdominal fascial closure in combat casualties undergoing exploratory laparotomy. Records of 1,977 combat casualties admitted to a single US military hospital from April 2003 to December 2011 were reviewed. Patients receiving an MT and laparotomy in theater constituted the study cohort. The cohort was divided into RDR, defined as a ratio of 0.8-U to 1.2-U packed red blood cells to 1-U fresh frozen plasma, and No-RDR groups. Age, injury patterns, mechanism of injury, injury severity, blood products, number of laparotomies, and days to fascial closure were collected. Assessed outcomes were number of days (early ≤ 2 days) and number of laparotomies to achieve fascial closure. The mean age of the study cohort (n = 172) was 24.0 years, and mean Injury Severity Score (ISS) was 24.8. Improvised explosive device blast was the most common mechanism of injury (74.4%). The cohort was divided into RDR patients (n = 73) and no RDR (n = 99). There was no difference in mean age, mean ISS, or rate of nontherapeutic exploratory laparotomies between the groups. RDR patients had a significantly lower abdominal injury rate (34.2% vs. 72.7%, p < 0.01), had fewer laparotomies (2.7 vs. 4.3, p = 0.003), and achieved primary fascial closure faster (2.4 days vs. 7.2 days, p = 0.004). On multivariate analysis, RDR (2.74; 95% confidence interval, 1.44-5.2) was an independent predictor for early fascial closure. Adherence to RDR guidelines resulted in significantly decreased number of abdominal operations and was identified as an independent predictor for early fascial closure. Further investigation is warranted to validate these findings. Therapeutic study, level III.
Percutaneous Closure of Patent Foramen Ovale in Patients With Migraine: The PREMIUM Trial.
Tobis, Jonathan M; Charles, Andrew; Silberstein, Stephen D; Sorensen, Sherman; Maini, Brijeshwar; Horwitz, Phillip A; Gurley, John C
2017-12-05
Migraine is a prevalent and disabling disorder. Patent foramen ovale (PFO) has been associated with migraine, but its role in the disorder remains poorly understood. This study examined the efficacy of percutaneous PFO closure as a therapy for migraine with or without aura. The PREMIUM (Prospective, Randomized Investigation to Evaluate Incidence of Headache Reduction in Subjects With Migraine and PFO Using the AMPLATZER PFO Occluder to Medical Management) was a double-blind study investigating migraine characteristics over 1 year in subjects randomized to medical therapy with a sham procedure (right heart catheterization) versus medical therapy and PFO closure with the Amplatzer PFO Occluder device (St. Jude Medical, St. Paul, Minnesota). Subjects had 6 to 14 days of migraine per month, had failed at least 3 migraine preventive medications, and had significant right-to-left shunt defined by transcranial Doppler. Primary endpoints were responder rate defined as 50% reduction in migraine attacks and adverse events. Secondary endpoints included reduction in migraine days and efficacy in patients with versus without aura. Of 1,653 subjects consented, 230 were enrolled. There was no difference in responder rate in the PFO closure (45 of 117) versus control (33 of 103) groups. One serious adverse event (transient atrial fibrillation) occurred in 205 subjects who underwent PFO closure. Subjects in the PFO closure group had a significantly greater reduction in headache days (-3.4 vs. -2.0 days/month, p = 0.025). Complete migraine remission for 1 year occurred in 10 patients (8.5%) in the treatment group versus 1 (1%) in the control group (p = 0.01). PFO closure did not meet the primary endpoint of reduction in responder rate in patients with frequent migraine. (Prospective, Randomized Investigation to Evaluate Incidence of Headache Reduction in Subjects With Migraine and PFO Using the AMPLATZER PFO Occluder to Medical Management [PREMIUM]; NCT00355056). Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
Sprong, Matthew Evan; Dallas, Bryan; Paul, Erina; Xia, Michelle
2018-05-03
The primary goal of the study was to evaluate how the use of rehabilitation technology impacted closure status for consumers receiving services in fiscal year (FY) 2014. Rehabilitation Service Administration (RSA-911) Case Service Report FY 2014 archival dataset was obtained from the U.S. Department of Education (2014) and secondary analyses was performed for this study. RSA-911 archival data is updated on an annual basis and consists of all state-federal rehabilitation consumers who were served in the specific fiscal year. The dataset contains information related to each consumer's demographic information (e.g. age, gender, race) and other supplemental information (e.g. weekly earnings at closure, cause of disability, services provided). A multiple logistic regression analysis was utilized and revealed that white consumers receiving rehabilitation technology (RT) services have significantly higher closure rate than consumers of other races, RT services differ by the employment status at application, RT services differ by the type of disability, educational level at application for people receiving RT services did predict closure status (i.e. exiting with an employment outcome), IEP status did not predict closure status, weekly earnings at application did predict closure status and the interaction effect between IEP and RT services is statistically significant. The odds ratio (ORs) were presented at the 95% confidence interval (CI). Vocational rehabilitation counselors needs training to correctly identify appropriate RT services for consumers, so that the likelihood of exiting with an employment outcome is obtained. Implications for Rehabilitation RT services significantly improved their chances of successful employment compared to those who did not receive RT services. Education at closure would also have some significant impact on employment outcomes. Training in Assistive Technology (AT) for Vocational Rehabilitation counselors will assist in the proper identification of AT requirements, which may lead to a higher likelihood of consumers exiting with an employment outcome.
Chen, Qiang; Cao, Hua; Zhang, Gui-Can; Chen, Liang-Wan; Chen, Dao-Zhong
2012-01-01
The study aims to evaluate the safety and feasibility of intra-operative device closure of atrial septal defect with transthoracic minimal invasion. From May 2006 to June 2009, 252 patients with secundum-type atrial septal defect closure were enrolled in our institution. The patients were divided into two groups, with 182 patients in group I with intra-operative device closure and 72 in group II with surgical closure. In group I, the patients' age ranged from 3 months to 62 years (mean±standard deviation, 19.0±16.7 years). This approach involved a transthoracic minimal invasion that was performed after full evaluation of the atrial septal defect by transthoracic echocardiography, deploying the device through the delivery sheath to occlude the atrial septal defect. In group I, 180 patients were occluded successfully under this approach. The size of the occluder device implanted ranged from 6 to 48 mm. Minor complications occurred, which included transient arrhythmias (n=23) and pleural effusion (n=15). Two patients with postoperative cardiac arrest were successfully cardiopulmonary resuscitated. Another two patients with occluder dislodged back into the right atrium were turned to surgical repair with cardiopulmonary bypass on the postoperative day. In group II, all patients were occluded successfully, and almost all patients needed blood transfusion and suffered from various minor complications. All discharged patients were followed up for 1-5 years. During this period, we found no recurrence, no thrombosis, even no device failure. In our comparative studies, group II had significantly longer intensive care unit (ICU) stay and hospital stay than group I (p<0.05). The cost for group I was less than group II (p<0.05). Intra-operative device closure of atrial septal defect with transthoracic minimal invasion is a safe and feasible technique. It had the advantages of cost savings, yielding better cosmetic results, and leaving less trauma than surgical closure.
Furlan, Anthony J; Reisman, Mark; Massaro, Joseph; Mauri, Laura; Adams, Harold; Albers, Gregory W; Felberg, Robert; Herrmann, Howard; Kar, Saibal; Landzberg, Michael; Raizner, Albert; Wechsler, Lawrence
2010-12-01
Some strokes of unknown etiology may be the result of a paradoxical embolism traversing through a nonfused foramen ovale (patent foramen ovale [PFO]). The utility of percutaneously placed devices for treatment of patients with cryptogenic stroke or transient ischemic attack (TIA) and PFO is unknown. In addition, there are no clear data about the utility of medical interventions or other surgical procedures in this situation. Despite limited data, many patients are being treated with PFO closure devices. Thus, there is a strong need for clinical trials that test the potential efficacy of PFO occlusive devices in this situation. To address this gap in medical knowledge, we designed the CLOSURE I trial, a randomized, clinical trial comparing the use of a percutaneously placed PFO occlusive device and best medical therapy versus best medical therapy alone for prevention of recurrent ischemic neurologic symptoms among persons with TIA or ischemic stroke. This prospective, multicenter, randomized, controlled trial has finished enrollment. Two-year follow-up for all 910 patients is required. The primary end point is the 2-year incidence of stroke or TIA, all-cause mortality for the first 30 days, and neurologic mortality from ≥ 31 days of follow-up, as adjudicated by a panel of physicians who are unaware of treatment allocation. This article describes the rationale and study design of CLOSURE I. This trial should provide information as to whether the STARFlex septal closure system is safe and more effective than best medical therapy alone in preventing recurrent stroke/TIA and mortality in patients with PFO and whether the STARFlex septal closure device can demonstrate superiority compared with best medical therapy alone. Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: NCT00201461.
Monfredi, Oliver; Luckie, Matthew; Mirjafari, Hoda; Willard, Terence; Buckley, Helen; Griffiths, Linda; Clarke, Bernard; Mahadevan, Vaikom S
2013-08-20
To investigate the echocardiographic effects of percutaneous closure of secundum atrial septal defect (ASD) in adults and assess which pre-closure parameters predict good response to closure. ASD is a common congenital heart disease often undiscovered until adulthood. ASD closure has been revolutionized by the use of percutaneous devices. The effects of these procedures on echocardiographic parameters are not well characterized. Patients undergoing percutaneous device closure of ASD between June 2007 and June 2009 had 3 sequential echocardiograms reviewed: pre-procedure, immediate post-procedure (24 hours) and 6-8 weeks post-procedure. Significant changes from baseline were investigated using paired t-test/1-way ANOVA. Pearson correlation (2-tailed) tests were used to categorize patients as 'good responders' to closure in terms of selected parameters. 129 echocardiograms in 43 consecutive patients were included. Remodeling of both ventricles occurred immediately following ASD closure and was sustained. Right ventricular (RV) diameter in diastole decreased by 13.5% and 19.3% compared to baseline at 24 hours and 6-8 weeks post-closure, respectively (p<0.05); Left ventricular (LV) diameter in diastole increased by 8.5% and 15.6%, respectively (p<0.05). Functional parameters of the RV also demonstrated early and sustained decreases (TAPSE decreased by 8.3% and 17% compared to baseline at 24 hours and 6-8 weeks post-closure, respectively (p<0.05)). Smaller RV baseline diameter appeared to predict good response to closure. Percutaneous ASD closure has immediate, sustained benefits on multiple echocardiographic parameters. Good responders have smaller RV at baseline, suggesting early closure is preferable. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
40 CFR 264.1202 - Closure and post-closure care.
Code of Federal Regulations, 2014 CFR
2014-07-01
... FACILITIES Hazardous Waste Munitions and Explosives Storage § 264.1202 Closure and post-closure care. (a) At... it remains in service as a munitions or explosives magazine or storage unit. (b) If, after removing...
40 CFR 264.1202 - Closure and post-closure care.
Code of Federal Regulations, 2011 CFR
2011-07-01
... FACILITIES Hazardous Waste Munitions and Explosives Storage § 264.1202 Closure and post-closure care. (a) At... it remains in service as a munitions or explosives magazine or storage unit. (b) If, after removing...
40 CFR 264.1202 - Closure and post-closure care.
Code of Federal Regulations, 2013 CFR
2013-07-01
... FACILITIES Hazardous Waste Munitions and Explosives Storage § 264.1202 Closure and post-closure care. (a) At... it remains in service as a munitions or explosives magazine or storage unit. (b) If, after removing...
40 CFR 264.1202 - Closure and post-closure care.
Code of Federal Regulations, 2012 CFR
2012-07-01
... FACILITIES Hazardous Waste Munitions and Explosives Storage § 264.1202 Closure and post-closure care. (a) At... it remains in service as a munitions or explosives magazine or storage unit. (b) If, after removing...
Marchand, D H; Snyder, L R; Dolan, J W
2008-05-16
A total of 371 reversed-phase columns have now been characterized in terms of selectivity, based on five solute-column interactions (the hydrophobic-subtraction model). The present study illustrates the use of these data for interpreting peak-tailing and column stability. New insights are also provided concerning column selectivity as a function of ligand and silica type, and the selection of columns for orthogonal separations is re-examined. Some suggestions for the quality control of reversed-phase columns during manufacture are offered.
Role of cathepsin S In periodontal wound healing-an in vitro study on human PDL cells.
Memmert, Svenja; Nokhbehsaim, Marjan; Damanaki, Anna; Nogueira, Andressa V B; Papadopoulou, Alexandra K; Piperi, Christina; Basdra, Efthimia K; Rath-Deschner, Birgit; Götz, Werner; Cirelli, Joni A; Jäger, Andreas; Deschner, James
2018-04-05
Cathepsin S is a cysteine protease, which is expressed in human periodontal ligament (PDL) cells under inflammatory and infectious conditions. This in vitro study was established to investigate the effect of cathepsin S on PDL cell wound closure. An in vitro wound healing assay was used to monitor wound closure in wounded PDL cell monolayers for 72 h in the presence and absence of cathepsin S. In addition, the effects of cathepsin S on specific markers for apoptosis and proliferation were studied at transcriptional level. Changes in the proliferation rate due to cathepsin S stimulation were analyzed by an XTT assay, and the actions of cathepsin S on cell migration were investigated via live cell tracking. Additionally, PDL cell monolayers were treated with a toll-like receptor 2 agonist in the presence and absence of a cathepsin inhibitor to examine if periodontal bacteria can alter wound closure via cathepsins. Cathepsin S enhanced significantly the in vitro wound healing rate by inducing proliferation and by increasing the speed of cell migration, but had no effect on apoptosis. Moreover, the toll-like receptor 2 agonist enhanced significantly the wound closure and this stimulatory effect was dependent on cathepsins. Our findings provide original evidence that cathepsin S stimulates PDL cell proliferation and migration and, thereby, wound closure, suggesting that this cysteine protease might play a critical role in periodontal remodeling and healing. In addition, cathepsins might be exploited by periodontal bacteria to regulate critical PDL cell functions.
Lilja, Jan; Mars, Michael; Elander, Anna; Enocson, Lars; Hagberg, Catharina; Worrell, Emma; Batra, Puneet; Friede, Hans
2006-09-01
To evaluate the dental arch relationships for a consecutive series from Goteborg, Sweden, who had delayed hard palate closure. Retrospective study. Sahlgrenska University Hospital, Goteborg, Sweden. The dental study models of 104 consecutive unilateral cleft lip and palate subjects. The study cohort was born between 1979 and 1994. Longitudinal records were available at ages 5 (n = 94), 10 (n = 97), 16 (n = 59), and 19 years (n = 46). Five assessors rated models according to the GOSLON Yardstick on two separate occasions each. These patients had been operated upon according to the Goteborg protocol of delayed hard palate closure (at age 8 years). 85% of subjects were rated in groups 1 and 2 (excellent or very good outcome), 12% were rated in group 3 (satisfactory), and 3% were assigned to group 4 (poor). No patients presented in Group 5 (very poor). Weighted kappa statistics for double determination of Yardstick allocation for five assessors demonstrated values between .65 and .90 for interrater agreement (good/very good) and between .70 and .90 for intrarater agreement (very good). Delayed hard palate closure as practiced in Goteborg since 1979 has produced the best GOSLON Yardstick ratings in a consecutive series of patients ever recorded worldwide, since the Yardstick was first used in 1983. However, it is noteworthy that a new protocol has been introduced in Goteborg since 1994, in which hard palate closure is done at 3 years due to concerns regarding speech.
Michalski, C W; Tramelli, P; Büchler, M W; Hackert, T
2017-01-01
Postoperative pancreatic fistulas represent the most frequent complication after distal and segmental pancreatectomy and occur with a frequency of up to 50 %. There are many technical variations of pancreatic stump treatment for reduction of fistula rates after distal resection. Most of these techniques have only been analyzed in retrospective studies and the evidence for or against a specific technique is low. Several retrospective trials have been conducted with good results to compare suturing with stapled closure of the remnant and to assess the effect of a vascularized falciform ligament patch in reducing postoperative pancreatic fistula; however, in a recently published randomized trial, which analyzed closure of the remnant with a pancreaticojejunostomy compared to standard closure, these results could not be confirmed. Because stapler resection and closure is the most commonly used technique in laparoscopic distal pancreatectomy, there are a large number of studies which assessed various novel methods of improving stapling. Extended stapler compression time and mesh augmentation of the stapler line can be valid methods to reduce fistula rates. Central pancreatectomy is a relatively rarely used procedure where the right-sided pancreatic remnant is closed in the same fashion as during distal pancreatectomy and the left-sided remnant is connected to the intestines with a pancreaticojejunostomy or pancreaticogastrostomy. In conclusion, postoperative pancreatic fistula rates are still a relevant clinical problem after distal pancreatectomy and further studies on potentially improved novel techniques are required.
Integrated fault seal analysis and risk assessemt: Okan and Meren Fields, Nigeria
DOE Office of Scientific and Technical Information (OSTI.GOV)
Eisenberg, R.A.; Brenneman, R.J.; Adepoju, A.A.
1996-01-01
Integration of production, geochemical, seismic, well log, and structural data provides important constraints on the sealing capacity and dynamic behavior of fault juxtaposed reservoirs in Okan and Meren fields, offshore Nigeria. Correlations were found between pressure decline histories, juxtaposed fluid types, oil composition, fluid contact relationships, fault sealing/leaking condition, and estimates of the composition of the fault gouge. Fault plane sections defined reservoir juxtapositions and potential cross-fault spill points. Smear gouge ratios calculated from E-logs were used to estimate the composition of fault-gouge materials between juxtaposed reservoirs. These tools augmented interpretation of seal/nonseal character in proved reservoirs and were usedmore » to quantify fault seal risk of untested, fault-dependent closures. In the Okan Field juxtapositions of the G-, H, L-, M, and O-sands were analyzed. Smear gouge ratios correlated to fluid contact relationships and pressure decline histories within these juxtaposed reservoirs empirically calibrate sealing potential. The results of these analyses were then used to interpret production-induced fault seal breakdown within the G-sands and to risk seal integrity of fault-dependent closures within the untested 0-sands in an adjacent, upthrown fault block. Within this fault block the presence of potential fault intersection leak points and large areas of sand/sand juxtaposition with high smear gouge ratios (low sealing potential) limits column heights and potential reserves within the O-sand package. In the Meren Field the E- and G-sands are juxtaposed, on different pressure decline, geochemically distinct, and are characterized by low smear gouge ratios. In contrast, the G- and H-sands, juxtaposed across the same fault, contain similar OOWCs and are characterized by high smear gouge ratios.« less
Integrated fault seal analysis and risk assessemt: Okan and Meren Fields, Nigeria
DOE Office of Scientific and Technical Information (OSTI.GOV)
Eisenberg, R.A.; Brenneman, R.J.; Adepoju, A.A.
Integration of production, geochemical, seismic, well log, and structural data provides important constraints on the sealing capacity and dynamic behavior of fault juxtaposed reservoirs in Okan and Meren fields, offshore Nigeria. Correlations were found between pressure decline histories, juxtaposed fluid types, oil composition, fluid contact relationships, fault sealing/leaking condition, and estimates of the composition of the fault gouge. Fault plane sections defined reservoir juxtapositions and potential cross-fault spill points. Smear gouge ratios calculated from E-logs were used to estimate the composition of fault-gouge materials between juxtaposed reservoirs. These tools augmented interpretation of seal/nonseal character in proved reservoirs and were usedmore » to quantify fault seal risk of untested, fault-dependent closures. In the Okan Field juxtapositions of the G-, H, L-, M, and O-sands were analyzed. Smear gouge ratios correlated to fluid contact relationships and pressure decline histories within these juxtaposed reservoirs empirically calibrate sealing potential. The results of these analyses were then used to interpret production-induced fault seal breakdown within the G-sands and to risk seal integrity of fault-dependent closures within the untested 0-sands in an adjacent, upthrown fault block. Within this fault block the presence of potential fault intersection leak points and large areas of sand/sand juxtaposition with high smear gouge ratios (low sealing potential) limits column heights and potential reserves within the O-sand package. In the Meren Field the E- and G-sands are juxtaposed, on different pressure decline, geochemically distinct, and are characterized by low smear gouge ratios. In contrast, the G- and H-sands, juxtaposed across the same fault, contain similar OOWCs and are characterized by high smear gouge ratios.« less
Effects of Irregular Bridge Columns and Feasibility of Seismic Regularity
NASA Astrophysics Data System (ADS)
Thomas, Abey E.
2018-05-01
Bridges with unequal column height is one of the main irregularities in bridge design particularly while negotiating steep valleys, making the bridges vulnerable to seismic action. The desirable behaviour of bridge columns towards seismic loading is that, they should perform in a regular fashion, i.e. the capacity of each column should be utilized evenly. But, this type of behaviour is often missing when the column heights are unequal along the length of the bridge, allowing short columns to bear the maximum lateral load. In the present study, the effects of unequal column height on the global seismic performance of bridges are studied using pushover analysis. Codes such as CalTrans (Engineering service center, earthquake engineering branch, 2013) and EC-8 (EN 1998-2: design of structures for earthquake resistance. Part 2: bridges, European Committee for Standardization, Brussels, 2005) suggests seismic regularity criterion for achieving regular seismic performance level at all the bridge columns. The feasibility of adopting these seismic regularity criterions along with those mentioned in literatures will be assessed for bridges designed as per the Indian Standards in the present study.
Oliver, Thomas A.; Oleson, Kirsten L. L.; Ratsimbazafy, Hajanaina; Raberinary, Daniel; Benbow, Sophie; Harris, Alasdair
2015-01-01
Overview Eight years of octopus fishery records from southwest Madagascar reveal significant positive impacts from 36 periodic closures on: (a) fishery catches and (b) village fishery income, such that (c) economic benefits from increased landings outweigh costs of foregone catch. Closures covered ~20% of a village’s fished area and lasted 2-7 months. Fishery Catches from Each Closed Site Octopus landings and catch per unit effort (CPUE) significantly increased in the 30 days following a closure’s reopening, relative to the 30 days before a closure (landings: +718%, p<0.0001; CPUE: +87%, p<0.0001; n = 36). Open-access control sites showed no before/after change when they occurred independently of other management (“no ban”, n = 17/36). On the other hand, open-access control sites showed modest catch increases when they extended a 6-week seasonal fishery shutdown (“ban”, n = 19/36). The seasonal fishery shutdown affects the entire region, so confound all potential control sites. Fishery Income in Implementing Villages In villages implementing a closure, octopus fishery income doubled in the 30 days after a closure, relative to 30 days before (+132%, p<0.001, n = 28). Control villages not implementing a closure showed no increase in income after “no ban” closures and modest increases after “ban” closures. Villages did not show a significant decline in income during closure events. Net Economic Benefits from Each Closed Site Landings in closure sites generated more revenue than simulated landings assuming continued open-access fishing at that site (27/36 show positive net earnings; mean +$305/closure; mean +57.7% monthly). Benefits accrued faster than local fishers’ time preferences during 17-27 of the 36 closures. High reported rates of illegal fishing during closures correlated with poor economic performance. Broader Co-Management We discuss the implications of our findings for broader co-management arrangements, particularly for catalyzing more comprehensive management. PMID:26083862
2015-01-01
Background School closure is considered as an effective measure to prevent pandemic influenza. Although Japan has implemented many class, grade, and whole school closures during the early stage of the pandemic 2009, the effectiveness of such a school closure has not been analysed appropriately. In addition, analysis based on evidence or data from a large population has yet to be performed. We evaluated the preventive effect of school closure against the pandemic (H1N1) 2009 and examined efficient strategies of reactive school closure. Materials and Methods Data included daily reports of reactive school closures and the number of infected students in the pandemic in Oita City, Japan. We used a regression model that incorporated a time delay to analyse the daily data of school closure based on a time continuous susceptible-exposed-infected-removed model of infectious disease spread. The delay was due to the time-lag from transmission to case reporting. We simulated the number of students infected daily with and without school closure and evaluated the effectiveness. Results The model with a 3-day delay from transmission to reporting yielded the best fit using R 2 (the coefficient of determination). This result suggests that the recommended period of school closure is more than 4 days. Moreover, the effect of school closure in the simulation of school closure showed the following: the number of infected students decreased by about 24% at its peak, and the number of cumulative infected students decreased by about 8.0%. Conclusions School closure was an effective intervention for mitigating the spread of influenza and should be implemented for more than 4 days. School closure has a remarkable impact on decreasing the number of infected students at the peak, but it does not substantially decrease the total number of infected students. PMID:26669757
ERIC Educational Resources Information Center
Xuan, Yue; Zhang, Zhaoyan
2014-01-01
Purpose: The purpose of this study was to explore the possible structural and material property features that may facilitate complete glottal closure in an otherwise isotropic physical vocal fold model. Method: Seven vocal fold models with different structural features were used in this study. An isotropic model was used as the baseline model, and…
Type of closure prevents microbial contamination of cosmetics during consumer use.
Brannan, D K; Dille, J C
1990-01-01
The dispensing closure used for containers plays an important role in protecting cosmetics from in-use microbial contamination. This hypothesis was tested by aseptically packing unpreserved shampoo and skin lotion into containers with three different closure types which provided various degrees of protection against consumer and environmental microbial insults. Shampoo was packed in containers with slit-cap (n = 25), flip-cap (n = 25), or screw-cap (n = 28) closures. Skin lotion was packed in containers with pump-top (n = 21), flip-cap (n = 18), or screw-cap (n = 21) closures. The products were then used by volunteers under actual in-use conditions for 3 (shampoo) or 2 (skin lotion) weeks. After use, the products were evaluated for microbial contamination by using standard methods for enumeration and identification. The standard screw-cap closure provided only minimal protection against microbial contamination of both the shampoo (29% contamination incidence) and the skin lotion (71%). The slit-cap closure on the shampoo container and the flip-cap closure on the skin lotion container provided slightly enhanced degrees of protection (21 and 39% contamination incidence, respectively). The greatest amount of protection (i.e., lowest contamination incidence) was provided by the flip-cap closure for the shampoo container (0%) and the pump-top closure for the skin lotion container (10%). As a result, closure type plays an important role in protecting poorly preserved products from in-use microbial contamination. Images PMID:2339896
Curry, Wayne; Conway, Samuel; Goodfield, Clara; Miller, Kimberly; Mueller, Ronald L; Polini, Eugene
2010-12-01
The preparation of sterile parenteral products requires careful control of all ingredients, materials, and processes to ensure the final product has the identity and strength, and meets the quality and purity characteristics that it purports to possess. Contamination affecting these critical properties of parenteral products can occur in many ways and from many sources. The use of closures supplied by manufacturers in a ready-to-use state can be an effective method for reducing the risk of contamination and improving the quality of the drug product. This article will address contamination attributable to elastomeric container closure components and the regulatory requirements associated with container closure systems. Possible contaminants, including microorganisms, endotoxins, and chemicals, along with the methods by which these contaminants can enter the product will be reviewed. Such methods include inappropriate material selection, improper closure preparation processes, compromised container closure integrity, degradation of closures, and leaching of compounds from the closures.
The Effect on Somatic Growth of Surgical and Catheter Treatment of Secundum Atrial Septal Defects.
Chlebowski, Meghan M; Dai, Hongying; Kaine, Stephen F
2017-10-01
Historical studies suggest an association between atrial septal defect (ASD) and impaired growth with inconsistent improvement following closure. Limited data exist regarding the impact on growth in the era of transcatheter therapy. To evaluate the effect of closure on growth, we conducted a retrospective review of patients undergoing surgical or transcatheter closure during two time periods. Four hundred patients with isolated secundum ASD were divided into three cohorts: early surgical, contemporary surgical, and transcatheter. Data collected included demographics; height, weight, and body mass index (BMI) percentiles; catheterization hemodynamics; and co-morbidities. For all cohorts, there was no significant change in height or weight percentiles during two years after ASD closure. Age at repair was later for contemporary surgical and transcatheter cohorts (p < 0.0001). In the transcatheter cohort, mean Qp:Qs was 1.65 ± 0.54, but there was no correlation between greater Qp:Qs and decreased somatic growth. Subgroup analysis for patients with any initial growth percentile <5th percentile demonstrated a significant change in weight and BMI percentiles in the first two years after closure (p < 0.0004). The advent of transcatheter therapy shifted institutional practice to later age at repair for both surgical and transcatheter closure. There was no significant change in weight and height percentiles during two years after closure. Only patients with initial weight and BMI <5th percentile had improved growth after treatment. Concern for impaired growth should not generally be an indication for early ASD repair. However, early repair may be indicated in children with existing significant growth failure.
A field evaluation of the Eye-Closure Interview with witnesses of serious crimes.
Vredeveldt, Annelies; Tredoux, Colin G; Nortje, Alicia; Kempen, Kate; Puljević, Cheneal; Labuschagne, Gérard N
2015-04-01
Laboratory research shows that eye-closure during memory retrieval improves both the amount and the factual accuracy of memory reports about witnessed events. Based on these findings, we developed the Eye-Closure Interview, and examined its feasibility (in terms of compliance with the instructions) and effectiveness (in terms of the quantity and quality of reported information) in eyewitness interviews conducted by the South African Police Service. Police interviewers from the Facial Identification Unit were randomly assigned to receive Eye-Closure Interview training or no training. We analyzed 95 interviews with witnesses of serious crimes (including robbery, rape, and murder), some of whom were instructed to close their eyes during salient parts of the interview. Witnesses in the control condition rarely spontaneously closed their eyes, but witnesses in the Eye-Closure Interview condition kept their eyes closed during 97% of their descriptions, suggesting that the Eye-Closure Interview would be easy to implement in a field setting. Although witnesses who closed their eyes did not remember more information overall, the information they provided was considered to be of significantly greater forensic relevance (as reflected in 2 independent blind assessments, 1 by a senior police expert and 1 by a senior researcher). Thus, based on the findings from this field study and from previous laboratory research, we conclude that implementation of the Eye-Closure Interview in witness interviews would help police interviewers to elicit more valuable information from witnesses, which could be relevant to the police investigation and/or in court. (PsycINFO Database Record (c) 2015 APA, all rights reserved).
Song, Ook; Kim, Kyung Hwan; Lee, Soo Young; Kim, Chang Hyun; Kim, Young Jin; Kim, Hyeong Rok
2018-04-01
The aim of this study was to identify the risk factors of stoma re-creation after closure of diverting ileostomy in patients with rectal cancer who underwent low anterior resection (LAR) or intersphincteric resection (ISR) with loop ileostomy. We retrospectively reviewed 520 consecutive patients with rectal cancer who underwent LAR or ISR with loop ileostomy from January 2005 to December 2014 at Chonnam National University Hwasun Hospital. Risk factors for stoma re-creation after ileostomy closure were evaluated. Among 520 patients with rectal cancer who underwent LAR or ISR with loop ileostomy, 458 patients underwent stoma closure. Among these patients, 45 (9.8%) underwent stoma re-creation. The median period between primary surgery and stoma closure was 5.5 months (range, 0.5-78.3 months), and the median period between closure and re-creation was 6.8 months (range, 0-71.5 months). Stoma re-creation was performed because of anastomosis-related complications (26, 57.8%), local recurrence (15, 33.3%), and anal sphincter dysfunction (3, 6.7%). Multivariate analysis showed that independent risk factors for stoma re-creation were anastomotic leakage (odds ratio [OR], 4.258; 95% confidence interval [CI], 1.814-9.993), postoperative radiotherapy (OR, 3.947; 95% CI, 1.624-9.594), and ISR (OR, 3.293; 95% CI, 1.462-7.417). Anastomotic leakage, postoperative radiotherapy, and ISR were independent risk factors for stoma re-creation after closure of ileostomy in patients with rectal cancer.
Angle assessment by EyeCam, goniophotography, and gonioscopy.
Baskaran, Mani; Perera, Shamira A; Nongpiur, Monisha E; Tun, Tin A; Park, Judy; Kumar, Rajesh S; Friedman, David S; Aung, Tin
2012-09-01
To compare EyeCam (Clarity Medical Systems, Pleasanton, CA) and goniophotography in detecting angle closure, using gonioscopy as the reference standard. In this hospital-based, prospective, cross-sectional study, participants underwent gonioscopy by a single observer, and EyeCam imaging and goniophotography by different operators. The anterior chamber angle in a quadrant was classified as closed if the posterior trabecular meshwork could not be seen. A masked observer categorized the eyes as per the number of closed quadrants, and an eye was classified as having angle closure if there were 2 or more quadrants of closure. Agreement between the methods was analyzed by κ statistic and comparison of area under receiver operating characteristic curves (AUC). Eighty-five participants (85 eyes) were included, the majority of whom were Chinese. Angle closure was detected in 38 eyes (45%) with gonioscopy, 40 eyes (47%) using EyeCam, and 40 eyes (47%) with goniophotography (P=0.69 in both comparisons, McNemar test). The agreement for angle closure diagnosis (by eye) between gonioscopy and the 2 imaging modalities was high (κ=0.86; 95% Confidence Interval (CI), 0.75-0.97), whereas the agreement between EyeCam and goniophotography was not as good (κ=0.72; 95% CI, 0.57-0.87); largely due to lack of agreement in the nasal and temporal quadrants (κ=0.55 to 0.67). The AUC for detecting eyes with gonioscopic angle closure was similar for goniophotography and EyeCam (AUC 0.93, sensitivity=94.7%, specificity=91.5%; P>0.95). EyeCam and goniophotography have similarly high sensitivity and specificity for the detection of gonioscopic angle closure.
Vijayalakshmi, Ishwarappa Balekundri; Setty, Natraj; Narasimhan, Chitra; Singla, Vivek; Manjunath, Cholenahalli Nanjappa
2014-12-01
Device closure of patent ductus arteriosus (PDA) is treatment of choice. But device closure in presence of pulmonary artery hypertension (PAH) remains a challenge. Data on patient selection, technical considerations, and complications are limited. To know the challenges and efficacy of device closure of PDA with PAH. Out of 1,325 cases of device closure of PDA, 246 (18.6%) with PAH formed the study material. To test the feasibility, chosen device is used to occlude PDA for ten minutes without oxygen inhalation. The device is released only if PAH reduced. PAH decreased in all except in 1 patient after closure with muscular ventricular septal occluder (MVSDO), pulmonary artery pressure (PAP) transiently increased (became supra-systemic), without significant reduction in aortic pressure. Device embolized in 8 patients (3.3%). Percutaneous retrieval was done in 4 (by snare in 2 and by fixing the cable to device in 2) and replaced with bigger devices. The surgical removal of the embolized MVSDO and ligation was done in 4 cases. All patients were on oral sildenafil and bosentan until PAP regressed to normal. Follow up was from 6 months to 9 years. No residual shunt in any patient on follow-up. The PAP regressed to normal in all except 5 cases (2.03%) of Down's syndrome with systemic PAP. Device closure of PDA with PAH is feasible, safe in all age groups. Temporary PDA occlusion with device is effective and time saving for evaluating pulmonary vascular reactivity. Device embolization in aorta is higher with severe PAH. Novel method of retrieval is effective. © 2014, Wiley Periodicals, Inc.
Klintö, Kristina; Svensson, Henry; Elander, Anna; Lohmander, Anette
2014-05-01
Objective : To describe and compare speech and phonology at age 3 years in children born with unilateral complete cleft lip and palate treated with three different methods for primary palatal surgery. Design : Prospective study. Setting : Primary care university hospitals. Participants : Twenty-eight Swedish-speaking children born with nonsyndromic unilateral complete cleft lip and palate. Interventions : Three methods for primary palatal surgery: two-stage closure with soft palate closure between 3.4 and 6.4 months and hard palate closure at mean age 12.3 months (n = 9) or 36.2 months (n = 9) or one-stage closure at mean age 13.6 months (n = 10). Main Outcome Measures : Based on independent judgments performed by two speech-language pathologists from standardized video recordings: percent correct consonants adjusted for age, percent active cleft speech characteristics, total number of phonological processes, number of different phonological processes, hypernasality, and audible nasal air leakage. The hard palate was unrepaired in nine of the children treated with two-stage closure. Results : The group treated with one-stage closure showed significantly better results than the group with an unoperated hard palate regarding percent active cleft speech characteristics and total number of phonological processes. Conclusions : Early primary palatal surgery in one or two stages did not result in any significant differences in speech production at age 3 years. However, children with an unoperated hard palate had significantly poorer speech and phonology than peers who had been treated with one-stage palatal closure at about 13 months of age.
Bradley, Paul M.; Journey, Celeste A.; Clark, Jimmy M.
2016-01-01
Wastewater treatment facility (WWTF) closures are rare environmental remediation events; offering unique insight into contaminant persistence, long-term wastewater impacts, and ecosystem recovery processes. The U.S. Geological Survey assessed the fate of select endocrine disrupting chemicals (EDC) in surface water and streambed sediment one year before and one year after closure of a long-term WWTF located within the Spirit Creek watershed at Fort Gordon, Georgia. Sample sites included a WWTF-effluent control located upstream from the outfall, three downstream effluent-impacted sites located between the outfall and Spirit Lake, and one downstream from the lake's outfall. Prior to closure, the 2.2-km stream segment downstream from the WWTF outfall was characterized by EDC concentrations significantly higher (α = 0.05) than at the control site; indicating substantial downstream transport and limited in-stream attenuation of EDC, including pharmaceuticals, estrogens, alkylphenol ethoxylate (APE) metabolites, and organophosphate flame retardants (OPFR). Wastewater-derived pharmaceutical, APE metabolites, and OPFR compounds were also detected in the outflow of Spirit Lake, indicating the potential for EDC transport to aquatic ecosystems downstream of Fort Gordon under effluent discharge conditions. After the WWTF closure, no significant differences in concentrations or numbers of detected EDC compounds were observed between control and downstream locations. The results indicated EDC pseudo-persistence under preclosure, continuous supply conditions, with rapid attenuation following WWTF closure. Low concentrations of EDC at the control site throughout the study and comparable concentrations in downstream locations after WWTF closure indicated additional, continuing, upstream contaminant sources within the Spirit Creek watershed.
ERIC Educational Resources Information Center
DePaoli, Jennifer; van Lier, Piet
2013-01-01
Ohio's charter-closure law is touted as one of the toughest in the nation because it requires the automatic closure of charter schools that consistently fail to meet academic standards. Ohio's charter-closure law, which became effective in 2008 and was revised in 2011, calls for automatic closure of schools rated in Academic Emergency for at least…
Transcatheter closure of ventricular septal defect with Occlutech Duct Occluder.
Atik-Ugan, Sezen; Saltik, Irfan Levent
2018-04-01
Patent ductus arteriosus occluders are used for transcatheter closure of ventricular septal defects, as well as for closure of patent ductus arteriosus. The Occlutech Duct Occluder is a newly introduced device for transcatheter closure of patent ductus arteriosus. Here, we present a case in which the Occlutech Duct Occluder was successfully used on a patient for the closure of a perimembraneous ventricular septal defect.
Fumanelli, Laura; Ajelli, Marco; Merler, Stefano; Ferguson, Neil M.; Cauchemez, Simon
2016-01-01
School closure policies are among the non-pharmaceutical measures taken into consideration to mitigate influenza epidemics and pandemics spread. However, a systematic review of the effectiveness of alternative closure policies has yet to emerge. Here we perform a model-based analysis of four types of school closure, ranging from the nationwide closure of all schools at the same time to reactive gradual closure, starting from class-by-class, then grades and finally the whole school. We consider policies based on triggers that are feasible to monitor, such as school absenteeism and national ILI surveillance system. We found that, under specific constraints on the average number of weeks lost per student, reactive school-by-school, gradual, and county-wide closure give comparable outcomes in terms of optimal infection attack rate reduction, peak incidence reduction or peak delay. Optimal implementations generally require short closures of one week each; this duration is long enough to break the transmission chain without leading to unnecessarily long periods of class interruption. Moreover, we found that gradual and county closures may be slightly more easily applicable in practice as they are less sensitive to the value of the excess absenteeism threshold triggering the start of the intervention. These findings suggest that policy makers could consider school closure policies more diffusely as response strategy to influenza epidemics and pandemics, and the fact that some countries already have some experience of gradual or regional closures for seasonal influenza outbreaks demonstrates that logistic and feasibility challenges of school closure strategies can be to some extent overcome. PMID:26796333
Fumanelli, Laura; Ajelli, Marco; Merler, Stefano; Ferguson, Neil M; Cauchemez, Simon
2016-01-01
School closure policies are among the non-pharmaceutical measures taken into consideration to mitigate influenza epidemics and pandemics spread. However, a systematic review of the effectiveness of alternative closure policies has yet to emerge. Here we perform a model-based analysis of four types of school closure, ranging from the nationwide closure of all schools at the same time to reactive gradual closure, starting from class-by-class, then grades and finally the whole school. We consider policies based on triggers that are feasible to monitor, such as school absenteeism and national ILI surveillance system. We found that, under specific constraints on the average number of weeks lost per student, reactive school-by-school, gradual, and county-wide closure give comparable outcomes in terms of optimal infection attack rate reduction, peak incidence reduction or peak delay. Optimal implementations generally require short closures of one week each; this duration is long enough to break the transmission chain without leading to unnecessarily long periods of class interruption. Moreover, we found that gradual and county closures may be slightly more easily applicable in practice as they are less sensitive to the value of the excess absenteeism threshold triggering the start of the intervention. These findings suggest that policy makers could consider school closure policies more diffusely as response strategy to influenza epidemics and pandemics, and the fact that some countries already have some experience of gradual or regional closures for seasonal influenza outbreaks demonstrates that logistic and feasibility challenges of school closure strategies can be to some extent overcome.
Cranioschisis aperta with encephaloschisis in cephalothoracopagus hamster twins.
Willhite, C C; Rossi, N L; Frakes, R A; Sharma, R P
1985-01-01
The results of gross and histopathological study of a near-term male hamster exencephalic lateral cephalothoracopagus are presented. There was minimal duplication of the internal organs to the point of division at the abdomen. The appendicular skeleton was relatively unaffected by the severe malformations of the axial skeleton. The studies suggested that the lateral relationship of the skull to the spinal columns was a consequence of the presence of two embryonic neural tubes; the chordomesodermal systems of the right and left twins apparently contributed the tissues for the right and left cephalic neural folds, respectively. Anomalies of the vertebral bodies and neural arches were not related to failure of closure of the neural tube as there was no evidence for rachischisis in either body half. Rather, the anomalous axial skeletal elements were apparently the result of competing fields of development by two chordomesodermal systems. The twins were recovered from a dam maintained on a diet consisting of 80% cassava, a cyanide-containing staple consumed by humans in tropical countries. Because the numbers of resorbed implantation sites and malformed litermates were low and the failure to produce conjoined twins in other litters recovered from dams given cassava diets, it appears unlikely that the malformation was related to the composition of the diet. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. Fig. 5. Fig. 6. PMID:4016585
3718-F Alkali Metal Treatment and Storage Facility Closure Plan
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
Since 1987, Westinghouse Hanford Company has been a major contractor to the U.S. Department of Energy-Richland Operations Office and has served as co-operator of the 3718-F Alkali Metal Treatment and Storage Facility, the waste management unit addressed in this closure plan. The closure plan consists of a Part A Dangerous waste Permit Application and a RCRA Closure Plan. An explanation of the Part A Revision (Revision 1) submitted with this document is provided at the beginning of the Part A section. The closure plan consists of 9 chapters and 5 appendices. The chapters cover: introduction; facility description; process information; wastemore » characteristics; groundwater; closure strategy and performance standards; closure activities; postclosure; and references.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
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This is document addresses the Federal regulations governing the closure of hazardous and mixed waste units subject to Resource Conservation and Recovery Act (RCRA) requirements. It provides a brief overview of the RCRA permitting program and the extensive RCRA facility design and operating standards. It provides detailed guidance on the procedural requirements for closure and post-closure care of hazardous and mixed waste management units, including guidance on the preparation of closure and post-closure plans that must be submitted with facility permit applications. This document also provides guidance on technical activities that must be conducted both during and after closure ofmore » each of the following hazardous waste management units regulated under RCRA.« less
Patel, Sunil V; Paskar, David D; Nelson, Richard L; Vedula, Satyanarayana S; Steele, Scott R
2017-11-03
Surgeons who perform laparotomy have a number of decisions to make regarding abdominal closure. Material and size of potential suture types varies widely. In addition, surgeons can choose to close the incision in anatomic layers or mass ('en masse'), as well as using either a continuous or interrupted suturing technique, of which there are different styles of each. There is ongoing debate as to which suturing techniques and suture materials are best for achieving definitive wound closure while minimising the risk of short- and long-term complications. The objectives of this review were to identify the best available suture techniques and suture materials for closure of the fascia following laparotomy incisions, by assessing the following comparisons: absorbable versus non-absorbable sutures; mass versus layered closure; continuous versus interrupted closure techniques; monofilament versus multifilament sutures; and slow absorbable versus fast absorbable sutures. Our objective was not to determine the single best combination of suture material and techniques, but to compare the individual components of abdominal closure. On 8 February 2017 we searched CENTRAL, MEDLINE, Embase, two trials registries, and Science Citation Index. There were no limitations based on language or date of publication. We searched the reference lists of all included studies to identify trials that our searches may have missed. We included randomised controlled trials (RCTs) that compared suture materials or closure techniques, or both, for fascial closure of laparotomy incisions. We excluded trials that compared only types of skin closures, peritoneal closures or use of retention sutures. We abstracted data and assessed the risk of bias for each trial. We calculated a summary risk ratio (RR) for the outcomes assessed in the review, all of which were dichotomous. We used random-effects modelling, based on the heterogeneity seen throughout the studies and analyses. We completed subgroup analysis planned a priori for each outcome, excluding studies where interventions being compared differed by more than one component, making it impossible to determine which variable impacted on the outcome, or the possibility of a synergistic effect. We completed sensitivity analysis, excluding trials with at least one trait with high risk of bias. We assessed the quality of evidence using the GRADEpro guidelines. Fifty-five RCTs with a total of 19,174 participants met the inclusion criteria and were included in the meta-analysis. Included studies were heterogeneous in the type of sutures used, methods of closure and patient population. Many of the included studies reported multiple comparisons.For our primary outcome, the proportion of participants who developed incisional hernia at one year or more of follow-up, we did not find evidence that suture absorption (absorbable versus non-absorbable sutures, RR 1.07, 95% CI 0.86 to 1.32, moderate-quality evidence; or slow versus fast absorbable sutures, RR 0.81, 95% CI 0.63 to 1.06, moderate-quality evidence), closure method (mass versus layered, RR 1.92, 95% CI 0.58 to 6.35, very low-quality evidence) or closure technique (continuous versus interrupted, RR 1.01, 95% CI 0.76 to 1.35, moderate-quality evidence) resulted in a difference in the risk of incisional hernia. We did, however, find evidence to suggest that monofilament sutures reduced the risk of incisional hernia when compared with multifilament sutures (RR 0.76, 95% CI 0.59 to 0.98, I 2 = 30%, moderate-quality evidence).For our secondary outcomes, we found that none of the interventions reduced the risk of wound infection, whether based on suture absorption (absorbable versus non-absorbable sutures, RR 0.99, 95% CI 0.84 to 1.17, moderate-quality evidence; or slow versus fast absorbable sutures, RR 1.16, 95% CI 0.85 to 1.57, moderate-quality evidence), closure method (mass versus layered, RR 0.93, 95% CI 0.67 to 1.30, low-quality evidence) or closure technique (continuous versus interrupted, RR 1.13, 95% CI 0.96 to 1.34, moderate-quality evidence).Similarily, none of the interventions reduced the risk of wound dehiscence whether based on suture absorption (absorbable versus non-absorbable sutures, RR 0.78, 95% CI 0.55 to 1.10, moderate-quality evidence; or slow versus fast absorbable sutures, RR 1.55, 95% CI 0.92 to 2.61, moderate-quality evidence), closure method (mass versus layered, RR 0.69, 95% CI 0.31 to 1.52, moderate-quality evidence) or closure technique (continuous versus interrupted, RR 1.21, 95% CI 0.90 to 1.64, moderate-quality evidence).Absorbable sutures, compared with non-absorbable sutures (RR 0.49, 95% CI 0.26 to 0.94, low-quality evidence) reduced the risk of sinus or fistula tract formation. None of the other comparisons showed a difference (slow versus fast absorbable sutures, RR 0.88, 95% CI 0.05 to 16.05, very low-quality evidence; mass versus layered, RR 0.49, 95% CI 0.15 to 1.62, low-quality evidence; continuous versus interrupted, RR 1.51, 95% CI 0.64 to 3.61, very low-quality evidence). Based on this moderate-quality body of evidence, monofilament sutures may reduce the risk of incisional hernia. Absorbable sutures may also reduce the risk of sinus or fistula tract formation, but this finding is based on low-quality evidence.We had serious concerns about the design or reporting of several of the 55 included trials. The comparator arms in many trials differed by more than one component, making it impossible to attribute differences between groups to any one component. In addition, the patient population included in many of the studies was very heterogeneous. Trials included both emergency and elective cases, different types of disease pathology (e.g. colon surgery, hepatobiliary surgery, etc.) or different types of incisions (e.g. midline, paramedian, subcostal).Consequently, larger, high-quality trials to further address this clinical challenge are warranted. Future studies should ensure that proper randomisation and allocation techniques are performed, wound assessors are blinded, and that the duration of follow-up is adequate. It is important that only one type of intervention is compared between groups. In addition, a homogeneous patient population would allow for a more accurate assessment of the interventions.
Cyclic performance of concrete-filled steel batten built-up columns
NASA Astrophysics Data System (ADS)
Razzaghi, M. S.; Khalkhaliha, M.; Aziminejad, A.
2016-03-01
Steel built-up batten columns are common types of columns in Iran and some other parts of the world. They are economic and have acceptable performance due to gravity loads. Although several researches have been conducted on the behavior of the batten columns under axial loads, there are few available articles about their seismic performance. Experience of the past earthquakes, particularly the 2003 Bam earthquake in Iran, revealed that these structural members are seismically vulnerable. Thus, investigation on seismic performance of steel batten columns due to seismic loads and providing a method for retrofitting them are important task in seismic-prone areas. This study aims to investigate the behavior of concrete-filled batten columns due to combined axial and lateral loads. To this end, nonlinear static analyses were performed using ANSYS software. Herein, the behaviors of the steel batten columns with and without concrete core were compared. The results of this study showed that concrete-filled steel batten columns, particularly those filled with high-strength concrete, may cause significant increases in energy absorption and capacity of the columns. Furthermore, concrete core may improve post-buckling behavior of steel batten columns.
Innovation of Iron Reinforcing Column of Partical From Frame of Light Steel
NASA Astrophysics Data System (ADS)
Ramadhan, M. R.; Faslih, A.; Umar, M. Z.
2018-05-01
Almost half of houses in Indonesia are using lightweight steel roof truss today. The phenomenon in the field is that lightweight steel roof truss can blend with mortar mixture. Thus this phenomenon is captured for later applied dynamically, creatively, and innovatively with new idioms such as reinforcement for columns. This research aims to investigate the comparison of the way of making and the price of the materials between the column material made of the light steel and the column material made of the iron reinforcement which is the most efficient. Type of research is qualitative with a comparative causal approach. This research is divided into several stages, namely; Literature study, column creation, and validation. This study concluds that the manufacture of column material from reinforcement is more efficient, than the lightweight steel column material. The reinforcement column material is more efficient because of the more effective way of making and the price of the working materials more economical than the lightweight steel column material. Lightweight steel columns can be used for public housing on condition made by experienced craftsmen to make the process faster, and the dimensions of lightweight steel can be scaled down to make it more economical.