Effect of Initial Volume on the Run-Out Behavior of Submerged Granular Columns

Background: Radial access is an increasingly common approach to coronary angiography whereby a radial artery compression device (RACD) is applied to achieve haemostasis following sheath removal. Current procedure recommends the removal of 5mL of air at 5-minutely intervals from the RACD; 45 minutes post angiogram sheath removal and 2 hours post PCI (Percutaneous Coronary Intervention) sheath removal. Haemostasis failure at the puncture site however was frequently reported and required re-insertion of air. Patients reported increased discomfort and, in 44% of elective cases, post-procedure stay was increased and discharge delayed by 30-180 minutes as a result of prolonged recovery time. Methods: Hospital procedure was revised to remove 3mL volume (air) at 5-minutely intervals from the RACD instead of 5mL. The RACD was also to remain untouched for 60 minutes post angiogram sheath removal and remained at 2 hours untouched post PCI sheath removal. A retrospective audit was conducted pre- and post-procedure change and included patients undergoing radial-access angiogram or PCI Results: A total of 258 cases were reviewed; 158 angiogram and 100 PCI. Initial volume of air used to achieve haemostasis was 10-18mLs and heparin dose administered was 2000-10,000units. Prior to procedure change, 5mL (air) was removed from the RACD and subsequently haemostasis failure occurred in 43.8% (35) of angiogram patients and 55.1% (27) of PCI patients. Following implementation of the 3mL procedure, haemostasis failure was reported in 12.8% (10) of angiogram patients and 19.6% (10) of PCI patients. Conclusion: Whilst total time taken to remove the RACD marginally increased, decreasing the volume of air removed from 5mL to 3mL significantly reduced the incidence of haemostasis failure. This effect was achieved without adjustment of anticoagulation dose or initial volume of air inserted into the RACD.

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Isotherms of CO 2 between 70 and 3000 atmospheres (Amagat densities between 200 and 600)

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1935.0232 ◽

1935 ◽

Vol 153 (878) ◽

pp. 214-224 ◽

Cited By ~ 60

Keyword(s):

Density Measurements ◽

Initial Volume ◽

Steel Container

In the previous paper the technique and results of isotherm measurements up to densities of 200 Amagat units were described. For higher densities, however, the method used has the disadvantage that either the final volumes of the gas will be very small or the initial volume must be very large. The first would lead to inaccurate density measurements, the second to an enlargement of the steel container, which must stand 3000 atmospheres pressure so that the apparatus would be rather bulky. The apparatus was therefore altered so that the piezometer could be filled and the normal volume determined under pressure, but, by taking this pressure between 20 to 50 atmospheres, use could be made of the isotherm measurements described in the previous paper.

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Structure-kinetic relationships of choriogonadotropin and related molecules

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1989.256.6.e721 ◽

1989 ◽

Vol 256 (6) ◽

pp. E721-E724

Author(s):

L. Liu ◽

J. L. Southers ◽

J. W. Cassels ◽

S. M. Banks ◽

R. E. Wehmann ◽

...

Keyword(s):

Rate Constants ◽

Volume Of Distribution ◽

Metabolic Clearance ◽

Clearance Rates ◽

Glycoprotein Hormone ◽

Core Fragment ◽

Initial Volume ◽

Human Choriogonadotropin ◽

Pregnancy Urine ◽

Volumes Of Distribution

To assess how profound differences in carbohydrate and/or polypeptide structures affect parameters of plasma disappearance of glycoprotein hormones, we calculated and compared the initial volume of distribution, rate constants, and metabolic clearance rates of several highly purified human choriogonadotropin (hCG) analogues in monkeys. hCG, deglycosylated hCG, desialylated hCG, or core fragment of hCG-beta purified from pregnancy urine (beta-core) was administered as a rapid intravenous injection to adult male cynomolgus monkeys (n = 3/group). The metabolic clearance rates of deglycosylated hCG, beta-core fragment, and desialylated hCG were increased 15-, 47-, and 152-fold, respectively, over that of hCG. Their corresponding initial volumes of distribution, however, remained essentially unchanged compared with that of hCG and approximated the estimated plasma volume. In contrast, the fast and slow rate constants of plasma disappearance of the hCG analogues were increased as much as 18- and 23-fold, respectively, relative to those of hCG. These studies of structure-kinetic relationships in primates show that major carbohydrate and polypeptide modifications of a glycoprotein hormone cause profound changes in the rate constants of the disappearance curves without changes in the initial volume of distribution.

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Numerical simulations of lock-exchange compositional gravity current

Journal of Fluid Mechanics ◽

10.1017/s0022112009007599 ◽

2009 ◽

Vol 635 ◽

pp. 361-388 ◽

Cited By ~ 77

Author(s):

SENG KEAT OOI ◽

GEORGE CONSTANTINESCU ◽

LARRY WEBER

Keyword(s):

High Resolution ◽

Dissipation Rate ◽

Friction Velocity ◽

Gravity Current ◽

Gravity Currents ◽

Inviscid Limit ◽

Grashof Number ◽

Front Speed ◽

Initial Volume ◽

Bed Friction

Compositional gravity current flows produced by the instantaneous release of a finite-volume, heavier lock fluid in a rectangular horizontal plane channel are investigated using large eddy simulation. The first part of the paper focuses on the evolution of Boussinesq lock-exchange gravity currents with a large initial volume of the release during the slumping phase in which the front of the gravity current propagates with constant speed. High-resolution simulations are conducted for Grashof numbers $\sqrt {Gr}$ = 3150 (LGR simulation) and $\sqrt {Gr}$ = 126000 (HGR simulation). The Grashof number is defined with the channel depth h and the buoyancy velocity ub = $\sqrt {g'h}$ (g′ is the reduced gravity). In the HGR simulation the flow is turbulent in the regions behind the two fronts. Compared to the LGR simulation, the interfacial billows lose their coherence much more rapidly (over less than 2.5h behind the front), which results in a much faster decay of the large-scale content and turbulence intensity in the trailing regions of the flow. A slightly tilted, stably stratified interface layer develops away from the two fronts. The concentration profiles across this layer can be approximated by a hyperbolic tangent function. In the HGR simulation the energy budget shows that for t > 18h/ub the flow reaches a regime in which the total dissipation rate and the rates of change of the total potential and kinetic energies are constant in time. The second part of the paper focuses on the study of the transition of Boussinesq gravity currents with a small initial volume of the release to the buoyancy–inertia self-similar phase. When the existence of the back wall is communicated to the front, the front speed starts to decrease, and the current transitions to the buoyancy–inertia phase. Three high-resolution simulations are performed at Grashof numbers between $\sqrt {Gr}$ = 3 × 104 and $\sqrt {Gr}$ = 9 × 104. Additionally, a calculation at a much higher Grashof number ($\sqrt {Gr}$ = 106) is performed to understand the behaviour of a bottom-propagating current closer to the inviscid limit. The three-dimensional simulations correctly predict a front speed decrease proportional to t−α (the time t is measured from the release time) over the buoyancy–inertia phase, with the constant α approaching the theoretical value of 1/3 as the current approaches the inviscid limit. At Grashof numbers for which $\sqrt {Gr}$ > 3 × 104, the intensity of the turbulence in the near-wall region behind the front is large enough to induce the formation of a region containing streaks of low and high streamwise velocities. The streaks are present well into the buoyancy–inertia phase before the speed of the front decays below values at which the streaks can be sustained. The formation of the velocity streaks induces a streaky distribution of the bed friction velocity in the region immediately behind the front. This distribution becomes finer as the Grashof number increases. For simulations in which the only difference was the value of the Grashof number ($\sqrt {Gr}$ = 4.7 × 104 versus $\sqrt {Gr}$ = 106), analysis of the non-dimensional bed friction velocity distributions shows that the capacity of the gravity current to entrain sediment from the bed increases with the Grashof number. Past the later stages of the transition to the buoyancy–inertia phase, the temporal variations of the potential energy, the kinetic energy and the integral of the total dissipation rate are logarithmic.

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Monitoring initial volume therapy after coronary bypass surgery by gastric tonometry

Critical Care ◽

10.1186/cc538 ◽

1999 ◽

Vol 3 (Suppl 1) ◽

pp. P165

Author(s):

H Vogelsang ◽

T Uhlig ◽

H Heinze ◽

P Schmucker

Keyword(s):

Bypass Surgery ◽

Coronary Bypass ◽

Coronary Bypass Surgery ◽

Gastric Tonometry ◽

Volume Therapy ◽

Initial Volume

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Efficient initial volume determination from electron microscopy images of single particles

Bioinformatics ◽

10.1093/bioinformatics/btu404 ◽

2014 ◽

Vol 30 (20) ◽

pp. 2891-2898 ◽

Cited By ~ 41

Author(s):

Javier Vargas ◽

Ana-Lucia Álvarez-Cabrera ◽

Roberto Marabini ◽

Jose M. Carazo ◽

C. O. S. Sorzano

Keyword(s):

Electron Microscopy ◽

Single Particles ◽

Volume Determination ◽

Initial Volume ◽

Microscopy Images

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Area-Based Estimation of the Initial Volume of Distribution and Elimination Rate Constant following Intravenous Bolus Injection

Journal of Pharmaceutical Sciences ◽

10.1002/jps.2600801109 ◽

1991 ◽

Vol 80 (11) ◽

pp. 1042-1050

Author(s):

Soo Peang Khor ◽

Stephen L. Johnson ◽

Michael Mayersohn

Keyword(s):

Rate Constant ◽

Bolus Injection ◽

Elimination Rate ◽

Volume Of Distribution ◽

Elimination Rate Constant ◽

Intravenous Bolus ◽

Intravenous Bolus Injection ◽

Initial Volume

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On lightning

Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character ◽

10.1098/rspa.1926.0048 ◽

1926 ◽

Vol 111 (757) ◽

pp. 56-67 ◽

Cited By ~ 31

Keyword(s):

Atmospheric Pressure ◽

Lightning Discharge ◽

Volume Charge ◽

Electrodeless Discharge ◽

Initial Volume ◽

First Case

A lightning discharge is a discharge of electricity through a gas at atmospheric pressure and can take three forms:— ( а ) A discharge between a part of the atmosphere having a volume charge of electricity, generally a cloud, and the ground. ( b ) A discharge between two parts of the atmosphere, each part having a definite volume charge of electricity, but of opposite signs. ( c ) A discharge from a part of the atmosphere having a volume charge into a part of the atmosphere in which no initial volume charge is present. In the first case the ground forms an electrode, but in the two latter cases the discharge does not pass between electrodes. In most studies of the discharge of electricity through gases the conditions at the surface of the electrodes form an important part in the discussion, and so far as I know the mechanism of an electrodeless discharge at atmospheric pressure has not been described.

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Mortalité du bois laissé sur pied à la suite d'une coupe par bandes dans trois régions du Québec

The Forestry Chronicle ◽

10.5558/tfc65107-2 ◽

1989 ◽

Vol 65 (2) ◽

pp. 107-113 ◽

Cited By ~ 10

Author(s):

Jean-Claude Ruel

Keyword(s):

Key Words ◽

Black Spruce ◽

Stand Volume ◽

Du Bois ◽

Strip Layout ◽

Initial Volume ◽

Stand Height

This paper presents the results of a three-year study of mortality in black spruce leave strips. The effects of various stand and strip layout characteristics are considered and recommendations for reducing blowdown are also provided.Mortality over the three years was highest in the Abitibi region of Quebec (20.2% of initial stand volume) and lowest in the Lac-Saint-Jean area (8.8% of initial stand volume). The Mauricie region was intermediate (17.4% of initial stand volumes). Most of the mortality occurred during the second year.In the Abitibi region, losses tended to increase in the leave strips when stand height was higher than 17 m and when leave strips were oriented SE to NW. In the Mauricie region, mortality increased with stand height and initial volume. In the Lac-Saint-Jean area, losses also increased with stand height but mortality remained relatively low. Key words: Black spruce, strip cutting, windthrow.

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