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1

Lumboperitoneal shunt for the treatment of leptomeningeal metastasis.  

PubMed

Leptomeningeal metastasis (LM) is thought to be a devastating and increasingly frequent neurological complication of cancer characterized by infiltration of malignant cells into the leptomeninges and the subarachnoid space. Intracranial hypertension and hydrocephalus are observed in about half of patients with LM. They are responsible for rapidly declining neurological status and eventual poor outcome in many patients with LM. Impediment of CSF circulation is considered the pathophysiological basis of increased intracranial pressure and hydrocephalus related to LM, which makes ventriculoperitoneal shunt (VP shunt) an acceptable palliative approach for LM now. It is noteworthy that LM generally causes communicating hydrocephalus. Lumboperitoneal shunt (LP shunt) has been demonstrated to be effective in the treatment of communicating hydrocephalus secondary to hemorrhage or infection, idiopathic intracranial hypertension and normal pressure hydrocephalus. And LP shunt has several advantages over VP shunt. Therefore we hypothesize that LP shunt can be used in the treatment of intracranial hypertension and hydrocephalus related to LM and should be given greater priority over VP shunt. PMID:25754849

Zhang, Xiao-Hui; Wang, Xiao-Guang; Piao, Ying-Zhe; Wang, Peng; Li, Peng; Li, Wen-Liang

2015-05-01

2

Laparoscopic-Assisted Lumboperitoneal Shunt: A Simplified Technique  

PubMed Central

Objectives: Lumboperitoneal shunt has been advocated as a better alternative to ventriculoperitoneal shunt in communicating hydrocephalus. To minimize the morbidity of subcutaneous tunneling or an open abdominal wound, we developed a simplified technique for laparoscopy-assisted placement of lumboperitoneal shunts. Methods: Patients deemed candidates for lumboperitoneal shunts underwent laparoscopy-assisted lumboperitoneal shunt placement. Using a Tuohy needle, the neurosurgeon obtains access to the lumbar subthecal space. Simultaneously, the laparoscopist obtains access to the peritoneal cavity with two 5-mm ports for the take down of the descending colon, clearing the way for the passage of the shunt passer from the back into the peritoneal cavity. Results: Over the last 5 years, 45 patients have undergone laparoscopy-assisted lumboperitoneal shunt placement. Patients have been followed with neuropsychiatric examinations, imaging studies, and repeated neurological examinations. No complications related to the laparoscopy have occurred. Neurosurgical complications included postural headaches caused by overdrainage in 4 patients requiring laparoscopic modification of the shunt slit and in 1 patient with acquired Arnold-Chiari I malformation. Conclusion: Laparoscopy-assisted lumboperitoneal shunt offers many advantages over percutaneous ventriculoperitoneal or laparoscopic transabdominal lumboperitoneal shunts. The procedure can be performed in less than 30 minutes by any practicing laparoscopist. PMID:11719975

Kirsch, Wolff; Robles, Antonio

2001-01-01

3

Miethke DualSwitch Valve in lumboperitoneal shunts  

Microsoft Academic Search

Introduction  Despite the existence of wide variety of shunt systems, physiological regulation of intracranial pressure in shunted patients\\u000a remains a utopian dream. Lumboperitoneal shunts (LPS) have long been used for treating idiopathic intracranial hypertension\\u000a and other types of “communicating” hydrocephalus. Although they can provide rapid and effective symptom resolution, cerebrospinal\\u000a fluid (CSF) over-drainage remains a common complication of LPS. We introduce

Suhas Udayakumaran; Jonathan Roth; Anat Kesler; Shlomi Constantini

2010-01-01

4

Assessment lumboperitoneal or ventriculoperitoneal shunt patency by radionuclide technique: a review experience cases.  

PubMed

Hydrocephalus-related symptoms that worsen after shunt placement may indicate a malfunctioning or obstructed shunt. The assessment of shunt patency and site of obstruction is important for planning of treatment. The radionuclide cerebrospinal fluid (CSF) shunt study provides a simple, effective, and low-radiation-dose method of assessing CSF shunt patency. The radionuclide CSF shuntography is a useful tool in the management of patients presenting with shunt-related problems not elucidated by conventional radiological examination. This article described the imaging technique of ventriculoperitoneal (VP) shunt and lumbar puncture (LP) shunt. The normal finding, abnormal finding of completed obstruction and partial obstruction is present by our cases experience. The radiopharmaceutical (Tc-99m diethylenetriaminepentaacetic acid) was injected via the reservoir for VP shunt and via lumbar puncture needle in subarachnoid space for LP shunt, then serial image in the head and abdominal area. The normal function of VP and LP shunt usually rapid spillage of the radioactivity in the abdominal cavity diffusely. The patent proximal tube VP shunt demonstrates ventricular reflux. The early image of patent LP shunt reveals no activity in the ventricular system contrast to distal LP shunt reveals early reflux of activity in the ventricular system. The completed distal VP and LP shunt obstruction show absence of tracer in the peritoneal area or markedly delayed appearance of abdominal activity. The partial distal VP and LP shunt obstruction recognized by slow transit or accumulation of tracer at the distal end or focal tracer in the peritoneal cavity near the tip of distal shunt. The images of the normal and abnormal CSF shunt as describe before are present in the full paper. Radionuclide CSF shuntography is a reliable and simple procedure for assessment shunt patency. PMID:25191120

Chiewvit, Sunanta; Nuntaaree, Sarun; Kanchaanapiboon, Potjanee; Chiewvit, Pipat

2014-05-01

5

Controversies: Optic nerve sheath fenestration versus shunt placement for the treatment of idiopathic intracranial hypertension  

PubMed Central

Background: Idiopathic intracranial hypertension (IIH) has been increasing in prevalence in the past decade, following the obesity epidemic. When medical treatment fails, surgical treatment options must be considered. However, controversy remains as to which surgical procedure is the preferred surgical option – optic nerve sheath fenestration (ONSF) or cerebrospinal fluid (CSF) shunting – for the long-term treatment of this syndrome. Purpose: To provide a clinical update of the pros and cons of ONSF versus shunt placement for the treatment of IIH. Design: This was a retrospective review of the current literature in the English language indexed in PubMed. Methods: The authors conducted a PubMed search using the following terms: Idiopathic IIH, pseudotumor cerebri, ONSF, CSF shunts, vetriculo-peritoneal shunting, and lumbo-peritoneal shunting. The authors included pertinent and significant original articles, review articles, and case reports, which revealed the new aspects and updates in these topics. Results: The treatment of IIH remains controversial and lacks randomized controlled clinical trial data. Treatment of IIH rests with the determination of the severity of IIH-related visual loss and headache. Conclusion: The decision for ONSF versus shunting is somewhat institution and surgeon dependent. ONSF is preferred for patients with visual symptoms whereas shunting is reserved for patients with headache. There are positive and negative aspects of both procedures, and a prospective, randomized, controlled trial is needed (currently underway). This article will hopefully be helpful in allowing the reader to make a more informed decision until that time. PMID:25449938

Spitze, Arielle; Lam, Peter; Al-Zubidi, Nagham; Yalamanchili, Sushma; Lee, Andrew G

2014-01-01

6

Ventriculoperitoneal shunting  

MedlinePLUS

Risks of anesthesia are: Reactions to medications Problems breathing Changes in blood pressure or breathing rate Risks of ventriculoperitoneal shunt placement are: Blood clot or bleeding in the brain Brain swelling Hole in the intestines (bowel ...

7

Adaptive piezoelectric shunt damping  

Microsoft Academic Search

Piezoelectric shunt damping systems reduce structural vibration by shunting an attached piezoelectric transducer with an electrical impedance. Current impedance designs result in a coupled electrical resonance at the target modal frequencies. In practical situations, variation in structural load or environmental conditions can result in significant changes in the structural resonance frequencies. This variation can severely reduce shunt damping performance as

Andrew J. Fleming; S. O. Reza Moheimani

2002-01-01

8

Impact of Cerebrospinal Fluid Shunting for Idiopathic Normal Pressure Hydrocephalus on the Amyloid Cascade  

PubMed Central

The aim of this study was to determine whether the improvement of cerebrospinal fluid (CSF) flow dynamics by CSF shunting, can suppress the oligomerization of amyloid ?-peptide (A?), by measuring the levels of Alzheimer’s disease (AD)-related proteins in the CSF before and after lumboperitoneal shunting. Lumbar CSF from 32 patients with idiopathic normal pressure hydrocephalus (iNPH) (samples were obtained before and 1 year after shunting), 15 patients with AD, and 12 normal controls was analyzed for AD-related proteins and APLP1-derived A?-like peptides (APL1?) (a surrogate marker for A?). We found that before shunting, individuals with iNPH had significantly lower levels of soluble amyloid precursor proteins (sAPP) and A?38 compared to patients with AD and normal controls. We divided the patients with iNPH into patients with favorable (improvement ? 1 on the modified Rankin Scale) and unfavorable (no improvement on the modified Rankin Scale) outcomes. Compared to the unfavorable outcome group, the favorable outcome group showed significant increases in A?38, 40, 42, and phosphorylated-tau levels after shunting. In contrast, there were no significant changes in the levels of APL1?25, 27, and 28 after shunting. After shunting, we observed positive correlations between sAPP? and sAPP?, A?38 and 42, and APL1?25 and 28, with shifts from sAPP? to sAPP?, from APL1?28 to 25, and from A?42 to 38 in all patients with iNPH. Our results suggest that A? production remained unchanged by the shunt procedure because the levels of sAPP and APL1? were unchanged. Moreover, the shift of A? from oligomer to monomer due to the shift of A?42 (easy to aggregate) to A?38 (difficult to aggregate), and the improvement of interstitial-fluid flow, could lead to increased A? levels in the CSF. Our findings suggest that the shunting procedure can delay intracerebral deposition of A? in patients with iNPH. PMID:25821958

Moriya, Masao; Miyajima, Masakazu; Nakajima, Madoka; Ogino, Ikuko; Arai, Hajime

2015-01-01

9

Adaptive electromagnetic shunt damping  

Microsoft Academic Search

This paper presents a new type of passive vibration control: adaptive electromagnetic shunt damping. We propose a single-mode resonant shunt controller that adapts to environmental conditions using two different adaptation strategies. The first technique is based on minimizing the root mean square (RMS) vibration, while the second minimizes the phase difference between two measurable signals. An experimental comparison shows that

Dominik Niederberger; Sam Behrens; Andrew J. Fleming; S. O. R. Moheimani; Manfred Morari

2006-01-01

10

residue and shunting pinholes  

NASA Astrophysics Data System (ADS)

The present work considers two observable phenomena through the experimental fabrication and electrical characterization of the rf-sputtered CdS/CdTe thin film solar cells that extremely reduce the overall conversion efficiency of the device: CdCl2 residue on the surface of the semiconductor and shunting pinholes. The former happens through nonuniform treatment of the As-deposited solar cells before annealing at high temperature and the latter occurs by shunting pinholes when the cell surface is shunted by defects, wire-like pathways or scratches on the metallic back contact caused from the external contacts. Such physical problems may be quite common in the experimental activities and reduce the performance down to 4-5 % which leads to dismantle the device despite its precise fabrication. We present our electrical characterization on the samples that received wet CdCl2 surface treatment (uniform or nonuniform) and are damaged by the pinholes.

Gorji, Nima E.

2014-09-01

11

LP Field, 2010  

USGS Multimedia Gallery

Rivers in middle Tennessee crested May 2-3,2010, breaking records at many USGS-operated streamgages. The flood peak on the Cumberland River in downtown Nashville ranks as the highest observed during the past 73 years. Flooding on the Cumberland River damaged the Grand Ole Opry House, LP Field (shown...

12

Laboratory study on "intracranial hypotension" created by pumping the chamber of a hydrocephalus shunt  

PubMed Central

Background It has been reported that pumping a shunt in situ may precipitate a proximal occlusion, and/or lead to ventricular over-drainage, particularly in the context of small ventricles. In the laboratory we measured the effect of pumping the pre-chamber of hydrocephalus shunts on intracranial hypotension. Materials and methods A simple physical model of the CSF space in a hydrocephalic patient was constructed with appropriate compliance, CSF production and circulation. This was used to test eleven different hydrocephalus shunts. The lowest pressure obtained, the number of pumps needed to reach this pressure, and the maximum pressure change with a single pump, were recorded. Results All models were able to produce negative pressures ranging from -11.5 mmHg (Orbis-Sigma valve) to -233.1 mmHg (Sinu-Shunt). The number of pumps required reaching these levels ranged from 21 (PS Medical LP Reservoir) to 315 (Codman Hakim-Programmable). The maximum pressure change per pump ranged from 0.39 mmHg (Orbis-Sigma valve) to 23.1 (PS Medical LP Reservoir). Conclusion Patients, carers and professionals should be warned that 'pumping' a shunt's pre-chamber may cause a large change in intracranial pressure and predispose the patient to ventricular catheter obstruction or other complications. PMID:17386089

Bromby, Adam; Czosnyka, Zofia; Allin, David; Richards, Hugh K; Pickard, John D; Czosnyka, Marek

2007-01-01

13

Robust passive piezoelectric shunt dampener  

Microsoft Academic Search

This paper introduces a new multiple mode passive piezoelectric shunt damping technique. The robust passive piezoelectric shunt controller is capable of damping multiple structural modes and maybe less susceptible to variations in environmental conditions that can severely effect the performance of other controllers. The proposed control scheme is validated experimentally on a piezoelectric laminated plate structure.

Sam Behrens; Andrew J. Fleming; S. O. R. Moheimani

2003-01-01

14

Over-shunting associated myelopathy.  

PubMed

Intracranial hypotension typically presents following cerebrospinal fluid (CSF) leak, but can be induced by CSF diversion. Classically, patients present with positional headache, but less common symptoms include neck pain and cranial nerve palsies. To our knowledge, the neurosurgical literature contains six reports of patients with symptomatic cervical, epidural venous plexus engorgement as the result of CSF shunting. The patient presented herein is a 26-year-old woman with shunt-dependent, congenital hydrocephalus. She presented with rapidly progressive cervical myelopathy following ventriculoperitoneal shunt revision. Imaging revealed engorgement of the cervical epidural venous plexus and mass effect on the cervical spinal cord. "Over-shunting associated myelopathy" is a rare complication of CSF diversion that should be familiar to physicians who routinely evaluate patients with intracranial shunts. PMID:25070631

Howard, Brian M; Sribnick, Eric A; Dhall, Sanjay S

2014-12-01

15

Hydrodynamic properties of hydrocephalus shunts: United Kingdom Shunt Evaluation Laboratory.  

PubMed Central

BACKGROUND: Although about 80% of properly diagnosed patients with hydrocephalus improve after implantation of any model of shunt, the remaining 20% may develop further complications because of inadequate shunt performance. Therefore, hydrocephalus shunts require careful independent laboratory evaluation. METHOD: Computer supported shunt testing, based on the new International Standard Organisation directives, characterises various aspects of pressure-flow performance of shunts such as variability with time, susceptibility to reflux, siphoning, temperature related behaviour, external pressure, the influence of a strong magnetic field (for example, MRI), presence of pulsation in differential pressure, particles in drained fluid, etc. RESULTS: Seven different models of valves, representing most common constructions, have been tested so far. Most contemporary valves have a hydrodynamic resistance which is too low. This may result in overdrainage both related to posture and during nocturnal cerebral vasogenic waves. A long distal catheter increases the resistance of these valves by 100%-200%. Most shunts are very sensitive to the presence of air bubbles and small particles in drained fluid. Few shunt models offer reasonable resistance to negative outlet pressure, preventing complications related to overdrainage. Valves with an antisiphon device may be blocked by raised subcutaneous pressure. All programmable valves are susceptible to overdrainage in an upright position. CONCLUSION: The behaviour of a valve during such testing is of immediate relevance to the surgeon and may not be adequately described in the manufacturer's product information. Images PMID:9010399

Czosnyka, M; Czosnyka, Z; Whitehouse, H; Pickard, J D

1997-01-01

16

An autonomous piezoelectric shunt damping system  

Microsoft Academic Search

Passive shunt damping involves the connection of an electrical shunt network to a structurally attached piezoelectric transducer. In recent years, a large body of research has focused on the design and implementation of shunt circuits capable of significantly reducing structural vibration. This paper introduces an efficient, light weight, and small-in-size technique for implementing piezoelectric shunt damping circuits. A MOSFET half

Andrew J. Fleming; Sam Behrens; S. O. R. Moheimani

2003-01-01

17

An Autonomous Piezoelectric Shunt Damping System  

Microsoft Academic Search

Passive shunt damping involves the connection of an electrical shunt network to a structurally attached piezoelec- tric transducer. In recent years, a large body of research has focused on the design and implementation of shunt circuits capable of significantly reducing structural vibration. This paper introduces an efficient, light weight, and small-in-size technique for implementing piezoelectric shunt damping circuits. A MOSFET

Andrew J. Fleming; Sam Behrens; S. O. Reza Moheimani

18

LP-80 IMU program status  

NASA Astrophysics Data System (ADS)

Development history, system design features, performance, and hardware status are reviewed for the fourth-generation LP-80 strapdown inertial measurement unit (IMU) which is currently in full-scale development to meet the design objectives required for missiles, torpedoes, drones, and range instrumentation system applications. The LP-80 is fully self-contained and operates at all attitudes, providing digital processed outputs of angular rate and linear acceleration measured in the body axis frame. For range applications, the LP-80 is designed to provide linear velocities with respect to a space stabilized coordinate frame.

Jackson, Edward N.

19

Registration of LP1-2581, LP1-2163H, LP3-1159, and LP640-1304 low phytate spring barley germplasm lines  

Technology Transfer Automated Retrieval System (TEKTRAN)

The Agricultural Research Service, U.S. Dept. of Agriculture (USDA-ARS) has developed and released four low-phytate spring barley (Hordeum vulgare L.) germplasm lines: LP1-2581 (Reg. No._____, PI 658245), LP1-2163H (Reg. No._____, PI 658248 ), LP3-1159 (Reg. No._____, PI 658247), and LP640-1304 (...

20

21 CFR 874.3820 - Endolymphatic shunt.  

Code of Federal Regulations, 2013 CFR

...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3820 Endolymphatic shunt. (a) Identification. An endolymphatic shunt is a device that...

2013-04-01

21

49 CFR 234.229 - Shunting sensitivity.  

Code of Federal Regulations, 2011 CFR

... 4 2011-10-01 2011-10-01 false Shunting sensitivity. 234.229 Section 234.229 Transportation Other...Testing Maintenance Standards § 234.229 Shunting sensitivity. Each highway-rail grade crossing train detection...

2011-10-01

22

49 CFR 236.56 - Shunting sensitivity.  

Code of Federal Regulations, 2011 CFR

... 4 2011-10-01 2011-10-01 false Shunting sensitivity. 236.56 Section 236.56 Transportation Other...Instructions: All Systems Track Circuits § 236.56 Shunting sensitivity. Each track circuit controlling home signal or...

2011-10-01

23

49 CFR 234.229 - Shunting sensitivity.  

Code of Federal Regulations, 2014 CFR

... 4 2014-10-01 2014-10-01 false Shunting sensitivity. 234.229 Section 234.229 Transportation Other...Testing Maintenance Standards § 234.229 Shunting sensitivity. Each highway-rail grade crossing train detection...

2014-10-01

24

49 CFR 236.56 - Shunting sensitivity.  

Code of Federal Regulations, 2013 CFR

... 4 2013-10-01 2013-10-01 false Shunting sensitivity. 236.56 Section 236.56 Transportation Other...Instructions: All Systems Track Circuits § 236.56 Shunting sensitivity. Each track circuit controlling home signal or...

2013-10-01

25

49 CFR 234.229 - Shunting sensitivity.  

Code of Federal Regulations, 2010 CFR

... 4 2010-10-01 2010-10-01 false Shunting sensitivity. 234.229 Section 234.229 Transportation Other...Testing Maintenance Standards § 234.229 Shunting sensitivity. Each highway-rail grade crossing train detection...

2010-10-01

26

49 CFR 236.56 - Shunting sensitivity.  

Code of Federal Regulations, 2014 CFR

... 4 2014-10-01 2014-10-01 false Shunting sensitivity. 236.56 Section 236.56 Transportation Other...Instructions: All Systems Track Circuits § 236.56 Shunting sensitivity. Each track circuit controlling home signal or...

2014-10-01

27

49 CFR 236.56 - Shunting sensitivity.  

Code of Federal Regulations, 2012 CFR

... 4 2012-10-01 2012-10-01 false Shunting sensitivity. 236.56 Section 236.56 Transportation Other...Instructions: All Systems Track Circuits § 236.56 Shunting sensitivity. Each track circuit controlling home signal or...

2012-10-01

28

49 CFR 236.56 - Shunting sensitivity.  

Code of Federal Regulations, 2010 CFR

... 4 2010-10-01 2010-10-01 false Shunting sensitivity. 236.56 Section 236.56 Transportation Other...Instructions: All Systems Track Circuits § 236.56 Shunting sensitivity. Each track circuit controlling home signal or...

2010-10-01

29

49 CFR 234.229 - Shunting sensitivity.  

Code of Federal Regulations, 2012 CFR

... 4 2012-10-01 2012-10-01 false Shunting sensitivity. 234.229 Section 234.229 Transportation Other...Testing Maintenance Standards § 234.229 Shunting sensitivity. Each highway-rail grade crossing train detection...

2012-10-01

30

49 CFR 234.229 - Shunting sensitivity.  

Code of Federal Regulations, 2013 CFR

... 4 2013-10-01 2013-10-01 false Shunting sensitivity. 234.229 Section 234.229 Transportation Other...Testing Maintenance Standards § 234.229 Shunting sensitivity. Each highway-rail grade crossing train detection...

2013-10-01

31

Cerebrospinal fluid shunt infection by Neisseria sicca.  

PubMed

Neisseria sicca is considered to be a nonpathogenic oral saprophyte. Presented here is an unusual case of cerebrospinal fluid (CSF) shunt infection by N. sicca. Although medical management of the common community-acquired meningitides, including infection by Neisseria meningitidis, is often successful in patients with CSF shunts, removal and replacement of the infected shunt was necessary in this case. PMID:7803309

Hornyik, G; Piatt, J H

1994-01-01

32

Cerebrospinal Fluid Shunt Infection by Neisseria sicca  

Microsoft Academic Search

Neisseria sicca is considered to be a nonpathogenic oral saprophyte. Presented here is an unusual case of cerebrospinal fluid (CSF) shunt infection by N. sicca. Although medical management of the common community-acquired meningitides, including infection by Neisseria meningitidis, is often successful in patients with CSF shunts, removal and replacement of the infected shunt was necessary in this case.

Galina Hornyik

1994-01-01

33

Passive vibration control via electromagnetic shunt damping  

Microsoft Academic Search

This work will present a new type of passive vibration control technique based on the concept of electromagnetic shunt damping. The proposed technique is similar to piezoelectric shunt damping, as an appropriately designed impedance is shunted across the terminals of the transducer. Theoretical and experimental results are presented for a simple electromagnetic mass spring damper system.

Sam Behrens; Andrew J. Fleming; S. O. Reza Moheimani

2005-01-01

34

Analytic approximation of matrix functions in Lp  

Microsoft Academic Search

We consider the problem of approximation of matrix functions of class Lp on the unit circle by matrix functions ana- lytic in the unit disk in the norm of Lp, 2 p < 1. For an m n matrix function in Lp, we consider the Hankel operator H : Hq(Cn) ! H2 (C m), 1=p + 1=q = 1=2. It

Laurent Baratchart; F. L. Nazarov; V. V. Peller

2009-01-01

35

WEIGHTED Lp -BOUNDEDNESS OF FOURIER SERIES  

E-print Network

Jacobi weight on the interval [-1, 1] and, for each function f, let Snf denote the n-th partial sum with respect to dµ. The study of the boundedness Snf Lp(updµ) C f Lp(vpdµ), (1) where u(x) = (1 - x)a (1 + x, . . . , N) (3) and A a, B b, Gi gi (4) hold, then C > 0 such that Snf Lp(updµ) C f Lp(vpdµ) f Lp (vp dµ

Pérez, Mario

36

[Transjugular portacaval shunt. Preliminary experience].  

PubMed

Transjugular intrahepatic portosystemic stent-shunt (TIPS) is a new technique in interventional radiology. This procedure is based on the creation of an intrahepatic channel between a main branch of the portal vein and an hepatic vein. A metallic stent is implanted to keep this shunt patent. From July 1990 to March 1992, 28 out of 32 patients with a history of gastric or esophageal variceal rebleeding, were treated by TIPS and followed for up to 20 months (mean 9.36 +/- 5.42). According to the Child Pugh's classification, 9 patients had class A cirrhosis, 17 class B and 6 class C. TIPS led to reduction of the portal pressure gradient by 57% and improvement of the portal blood flow by 250%. Early complications were: one technique-related death due to a medial stent implantation on the portal bifurcation (massive extrahepatic bleeding), other cases consisted of hemobilias (3 patients), intra-abdominal bleeding (1 patient) and gastrointestinal bleedings (4 patients). All of the complications except the deat were spontaneously reversed after withdrawal of Heparin. Follow-up showed a considerable improvement of ascites, seen in 55% of the patients with 100% reduction or disappearance after 3 months. Duplex-sonography follow-up found shunt stenosis in 43% of the patients, allowing preventive redilatation to restore patency of the shunt. Variceal rebleeding occurred in 20% of cases. These results remain interesting with regard to the high risk of bleeding in the patients of this preliminary study.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8215163

Perarnau, J M; Raabe, J J; Schwing, D; Rucin, B; Arbogast, J; Rössle, M

1993-01-01

37

Arterioportal shunts on dynamic computed tomography  

SciTech Connect

Thirty-two patients, 20 with hepatocelluar carcinoma and 12 with liver cirrhosis, were examined by dynamic computed tomography (CT) using intravenous bolus injection of contrast medium and by celiac angiography. Dynamic CT disclosed arterioportal shunting in four cases of hepatocellular carcinoma and in one of cirrhosis. In three of the former, the arterioportal shunt was adjacent to a mass lesion on CT, suggesting tumor invasion into the portal branch. In one with hepatocellular carcinoma, the shunt was remote from the mass. In the case with cirrhosis, there was no mass. In these last two cases, the shunt might have been caused by prior percutaneous needle puncture. In another case of hepatocellular carcinoma, celiac angiography but not CT demonstrated an arterioportal shunt. Thus, dynamic CT was diagnostic in five of six cases of arteriographically demonstrated arterioportal shunts.

Nakayama, T.; Hiyama, Y.; Ohnishi, K.; Tsuchiya, S.; Kohno, K.; Nakajima, Y.; Okuda, K.

1983-05-01

38

Radiological Insertion and Management of Peritoneovenous Shunt  

SciTech Connect

The purpose of the study was to report our experience of the management of complications following the insertion of a peritoneovenous shunt for intractable malignant ascites. From June 1999 to January 2006, 26 patients underwent insertion of a peritoneovenous shunt for ascites by interventional radiologists. We have used ultrasound and shuntography to assist in the diagnosis of the cause of shunt blockage. Successful techniques for the restoration of the shunt function include port- pumping, stripping of any fibrin sheath, and revision of either the venous or peritoneal catheter. The procedure was initially successful in all patients with continued patency until death in 17. A further four patients are still alive with a functioning shunt. There was one rapid postprocedure death resulting from pulmonary edema. Two patients developed pneumothorax, managed successfully with either a chest drain or aspiration. Shunt dysfunction occurred eight times in seven patients. There were five successful revisions in four patients. Overall, shunt patency has been maintained in 80.1% of patients. Shunt dysfunction is seen in a significant number of patients, but successful revision of the shunt can be achieved in the majority.

Bratby, M. J. [St George's Hospital, Radiology Department (United Kingdom); Hussain, F. F., E-mail: fhussain@doctors.org.uk; Lopez, A. J. [Royal Surrey County Hospital and St. Luke's Cancer Centre, Radiology Department (United Kingdom)

2007-06-15

39

The shunt-driven circular loop antenna  

Microsoft Academic Search

The distribution of current, admittance, and far field of a shunt-driven circular loop antenna are derived and related to those of an equivalent series-driven loop in parallel with a section of transmission line. The effective length of a shunt-loaded receiving antenna is obtained in terms of the corresponding quantity for the series-loaded loop.

R. King

1971-01-01

40

Cerebrospinal fluid shunt infections in children  

Microsoft Academic Search

A total of 431 patients who underwent their first cerebrospinal fluid shunt insertion at Children's Memorial Hospital over a 10-year period were retrospectively studied with regard to the relationship between the etiology of the hydrocephalus, age at the time of shunt placement, and infection rate. Forty percent of the patients had constrictive hydrocephalus and meningomyelocele, 33% congenital communicating or obstructive

Mario Ammirati; Anthony J. Raimondi

1987-01-01

41

Bidirectional shunt in uncomplicated atrial septal defect  

Microsoft Academic Search

The presence of right to left shunts at atrial level in 40 patients with an uncomplicated atrial septal defect was determined by measuring the pulmonary vein to systemic artery oxygen stepdown . In six patients (group 1) a sizeable right to left shunt was found: left atrial oxygen stepdown was greater than or equal to 0.7 vol%, mean right to

E Galve; J Angel; A Evangelista; I Anivarro; G Permanyer-Miralda; J Soler-Soler

1984-01-01

42

Congenital Portosystemic Shunt: Our Experience  

PubMed Central

Introduction. Congenital portosystemic venous malformations are rare abnormalities in which the portal blood drains into a systemic vein and which are characterized by extreme clinical variability. Case Presentations. The authors present two case reports of a congenital extrahepatic portosystemic shunt (Type II). In the first patient, apparently nonspecific symptoms, such as headache and fatigue, proved to be secondary to hypoglycemic episodes related to the presence of a portosystemic shunt, later confirmed on imaging. During portal vein angiography, endovascular embolization of the portocaval fistula achieved occlusion of the anomalous venous tract. In the second patient, affected by Down's syndrome, the diagnosis of a portosystemic malformation was made by routine ultrasonography, performed to rule out concurrent congenital anomalies. Because of the absence of symptoms, we chose to observe this patient. Conclusions. These two case reports demonstrate the clinical heterogeneity of this malformation and the need for a multidisciplinary approach. As part of a proper workup, clinical evaluation must always be followed by radiographic diagnosis. PMID:25709849

Timpanaro, Tiziana; Passanisi, Stefano; Sauna, Alessandra; Trombatore, Claudia; Pennisi, Monica; Petrillo, Giuseppe; Smilari, Pierluigi; Greco, Filippo

2015-01-01

43

75 FR 39680 - Houston Pipe Line Company LP, Worsham-Steed Gas Storage, L.P., Energy Transfer Fuel, LP, Mid...  

Federal Register 2010, 2011, 2012, 2013, 2014

...PR10-50-000] Houston Pipe Line Company LP, Worsham-Steed Gas Storage, L.P., Energy Transfer Fuel, LP, Mid Continent Market Center, L.L.C., Oasis Pipeline, LP (Not Consolidated); Notice of Baseline Filings July 2, 2010. Take...

2010-07-12

44

Scintisplenoportography in assessing patency of distal splenorenal shunts  

SciTech Connect

Scintisplenoportography was performed on 33 occasions in 28 cirrhotic patients who had bled from esophagogastric varices. In 17 cases scintisplenoportography was carried out after a retroperitoneal distal splenorenal shunt procedure and in the remaining 16 instances in patients without any surgical shunt. In four patients scintisplenoportography was performed before and after a surgical shunt procedure, and in one case, before and after the shunt thrombosed. Gammagraphic patterns and spleen-heart times helped determine which patients did not have a surgical shunt, which had a patent shunt, and which patients had a thrombosed shunt. A patent shunt pattern and a thrombosed shunt pattern have been defined. It is concluded that scintisplenoportography is a useful, reproducible, and safe method to assess the patency of distal splenorenal shunts.

Teres, J.; Herranz, R.; Visa, J.; Lomena, F.; Pera, C.; Rodes, J.

1983-06-01

45

Acute Shunt Malfunction Caused by Percutaneous Endoscopic Gastrostomy without Shunt Infection  

PubMed Central

Percutaneous endoscopic gastrostomy tube placement is often performed in patients with a ventriculoperitoneal shunt and it has been accepted as a safe procedure. The authors report a case of a 50-year-old male who developed acute exacerbation of the hydrocephalus immediately after the percutaneous endoscopic gastrostomy tube placement without any signs of shunt infection, which has not been reported until now. After revision of the intraperitoneal shunt catheter, the sizes of the intracranial ventricles were normalized. PMID:25371790

Choi, Jingyu; Ki, Seung Seog

2014-01-01

46

Fasciocutaneous flap in esophageal stricture with ventriculoperitoneal shunt.  

PubMed

Abdominal surgery in a patient with ventriculoperitoneal shunt may increase the risk of shunt malfunction and infection. We present a successful case of resection and reconstruction of the cervical esophagus by rolled lateral thoracic artery fasciocutaneous flap in a patient with corrosive esophageal stricture and preexisting ventriculoperitoneal shunt. Follow-up esophagogastroscopy after 3 months revealed wide patent graft. Rolled fasciocutaneous flap may be a safe alternative treatment without risk of shunt-associated complications in a patient with ventriculoperitoneal shunt. PMID:24384193

Seong, Yong Won; Kang, Chang Hyun; Chang, Hak; Park, In Kyu; Kim, Young Tae

2014-01-01

47

21 CFR 874.3820 - Endolymphatic shunt.  

Code of Federal Regulations, 2014 CFR

...3820 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3820 Endolymphatic shunt. (a) Identification....

2014-04-01

48

21 CFR 874.3820 - Endolymphatic shunt.  

Code of Federal Regulations, 2010 CFR

...3820 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3820 Endolymphatic shunt. (a) Identification....

2010-04-01

49

21 CFR 874.3820 - Endolymphatic shunt.  

Code of Federal Regulations, 2012 CFR

...3820 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3820 Endolymphatic shunt. (a) Identification....

2012-04-01

50

21 CFR 874.3820 - Endolymphatic shunt.  

Code of Federal Regulations, 2011 CFR

...3820 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3820 Endolymphatic shunt. (a) Identification....

2011-04-01

51

Cerebrospinal fluid eosinophilia associated with intraventricular shunts.  

PubMed

CSF eosinophilia (CSF-eo) is uncommon and is usually caused by helminthic infections. However, it has also been found in ?30% of patients experiencing intraventricular shunt malfunctions. We present a case report and review the conditions associated with CSF-eo and their prophylaxis. An 8 year-old boy with tetraventricular hydrocephalus has had several shunt malfunctions over the last three years. During hospitalization in January 2009 for shunt revision, a transient 30% eosinophilia was detected in his cerebral spinal fluid (CSF) concomitant with Staphylococcus epidermidis infection and long term vancomycin administration. After several shunt replacements and antibiotic treatment, CSF-eo eventually disappeared with good overall clinical response. CSF-eo is a transient and focal event mainly associated with infection, reactions to foreign substances, particles or blood, or obstruction of tubing by normal or fibro-granulomatous tissues. Infection associated with CSF-eo is usually caused by S. epidermidis and Propioniumbacterium acnes. In addition to infection, allergy to silicone and other foreign materials may also be a cause of CSF-eo. We review the diversity of conditions and proposed mechanisms associated with CSF-eo, as well as recommendations for the care of patients with shunts. Detection of CSF-eo has been shown to be a useful indicator of shunt malfunction. As such, it provides physicians with an indicator of a hypersensitivity reaction that is underway or the need to identify bacterial infection. We also highlight the need for improved biocompatibility of shunt hardware and describe strategies to avoid conditions leading to shunt malfunction. PMID:21492998

Bezerra, Sofia; Frigeri, Thomas More; Severo, Carlos Marcelo; Santana, João Carlos Batista; Graeff-Teixeira, Carlos

2011-06-01

52

Magnetoresistance of Metal-Shunted Graphene Devices  

NASA Astrophysics Data System (ADS)

Graphene, a single atomic layer of hexagonally arranged carbon atoms, presents the optimal platform to study magnetoresistance (MR) effects because of its temperature-independent mobility and linear band structure with zero band gap. Extraordinary magnetoresistance (EMR) can be realized in metal-shunted graphene devices. Here, due to the different magnetic-field-dependent resistances of the metallic shunt, graphene, and shunt-graphene interface, current flows easily through the shunt in zero and low magnetic field, while in high magnetic field, more current flows around the shunt and is redistributed in the graphene. Devices made from chemical vapor deposition (CVD) graphene grown on copper and transferred to a SiO2/Si substrate with Ti/Au shunts display gate-tunable longitudinal MR of ˜600% at 12 T and also show promise for use as Hall sensors. Graphene magnetoresistance devices have many possible applications including magnetic field sensors and magnetic read-heads. In contrast with the many proposed electronic uses for graphene, which necessitate the creation of a band-gap, graphene magnetoresistance devices that exploit LMR or EMR provide a use for as-grown or deposited graphene.

Campbell, Paul; Friedman, Adam; Perkins, F. Keith; Robinson, Jeremy

2011-03-01

53

H-Graft Portacaval Shunts Versus TIPS  

PubMed Central

Objective: To report long-term outcome of patients undergoing prosthetic 8-mm H-graft portacaval shunts (HGPCS) or TIPS and to compare actual with predicted survival data. Methods: A randomized trial comparing TIPS to HGPCS for bleeding varices began in 1993. Predicted survival was determined using MELD (Model for End-stage Liver Disease). Results: Patients undergoing TIPS (N = 66) or HGPCS (N = 66) were very similar by Child's class and MELD scores and predicted survival. After TIPS (P = 0.01) and HGPCS (P = 0.001), actual survival was superior to predicted survival. Through 24 months, actual survival after HGPCS was superior to actual survival after TIPS (P = 0.04). Compared with TIPS, survival was superior after HGPCS for patients of Child's class A and B (P = 0.07) and with MELD scores less than 13 (P = 0.04) with follow-up at 5 to 10 years. Shunt failure was less following HGPCS (P < 0.01). Conclusions: Predicted survival data for patients undergoing TIPS or HGPCS confirms an unbiased randomization. Actual survival following TIPS or HGPCS was superior to predicted survival. Shunt failure favored HGPCS, as did survival after shunting, particularly for the first few years after shunting and for patients of Child's class A or B or with MELD scores less than 13. This trial irrefutably establishes a role for surgical shunting, particularly HGPCS. PMID:15650633

Rosemurgy, Alexander S.; Bloomston, Mark; Clark, Whalen C.; Thometz, Donald P.; Zervos, Emmanuel E.

2005-01-01

54

Endoscopic Third Ventriculostomy in Previously Shunted Children  

PubMed Central

Endoscopic third ventriculostomy (ETV) is a routine and safe procedure for therapy of obstructive hydrocephalus. The aim of our study is to evaluate ETV success rate in therapy of obstructive hydrocephalus in pediatric patients formerly treated by ventriculoperitoneal (V-P) shunt implantation. From 2001 till 2011, ETV was performed in 42 patients with former V-P drainage implantation. In all patients, the obstruction in aqueduct or outflow parts of the fourth ventricle was proved by MRI. During the surgery, V-P shunt was clipped and ETV was performed. In case of favourable clinical state and MRI functional stoma, the V-P shunt has been removed 3 months after ETV. These patients with V-P shunt possible removing were evaluated as successful. In our group of 42 patients we were successful in 29 patients (69%). There were two serious complications (4.7%)—one patient died 2.5 years and one patient died 1 year after surgery in consequence of delayed ETV failure. ETV is the method of choice in obstructive hydrocephalus even in patients with former V-P shunt implantation. In case of acute or scheduled V-P shunt surgical revision, MRI is feasible, and if ventricular system obstruction is diagnosed, the hydrocephalus may be solved endoscopically. PMID:23984061

Chlachula, Martin; Hrbac, Tomas; Lipina, Radim

2013-01-01

55

Kernel Lattice Parallelism (KeLP)  

NSDL National Science Digital Library

KeLP (Kernel Lattice Parallelism) is a framework for implementing portable scientific applications on distributed memory parallel computers. It is intended for applications with special needs, in particular, that adapt to data-dependent or hardware dependent conditions at run time. KeLP is currently used in full-scale applications including subsurface modeling, turbulence studies, and first principles simulation of real materials.

56

Reduction of ventricular size after shunting for normal pressure hydrocephalus related to CSF dynamics before shunting  

Microsoft Academic Search

Reduction of ventricular size was determined by repeated computed tomography in 30 adult patients shunted for normal pressure hydrocephalus (NPH) and related to the pressure-volume index (PVI) and resistance to outflow of cerebrospinal fluid (Rcsf) measured before shunting. Rapid and marked reduction of ventricular size (n = 10) was associated with a significantly lower PVI than slow and moderate to

J T Tans; D C Poortvliet

1988-01-01

57

Ventriculoperitoneal shunts for hydrocephalus: a focus group discussion on the selection of shunt systems in pediatrics  

Microsoft Academic Search

As part of the Continuing Quality Improvement Study, phase I, 12 pediatric neurosurgeons participated in a discussion group to respond to the various issues related to selection of ventriculoperitoneal shunt systems in their practice. It was estimated that between then all the 12 participants performed approximately 1200 shunt procedures per year in the USA. The data were analyzed by grid

Hector E. James; Derek A. Bruce

1995-01-01

58

Peritoneovenous Shunt Scintigraphy to Assess Shunt Patency in Patients with Refractory Ascites  

PubMed Central

Peritoneovenous shunt scintigraphy is an infrequently performed study to non-invasively assess shunt patency in patients with recurrent or refractory ascites in cirrhotic patients. We describe two patients of chronic liver disease in whom 99mTc-macroaggregated albumin scintigraphy was performed to assess the patency of peritoneovenous shunt. Visualization of lung activity was interpreted as indicative of shunt patency. While both lungs were visualized almost immediately in the first patient, they were visualized by 30 min in the second patient. Visualization of radiolabeled peritoneal fluid in the entire length of the shunt tubing may be variable, and was seen in only one patient. Scintigraphy also helped in excluding communication between the ascites and right groin collection in the second patient.

Senthil, Raja; Sundaraiya, Sumati; Perumalla, Rajasekhar; Rela, Mohamed

2013-01-01

59

Reconstitution of shunted mantle in experimental hydrocephalus.  

PubMed

The morphological mechanism of the reconstitution of shunted mantle was studied histopathologically in 22 kaolin-treated hydrocephalic puppies. A remarkable attenuation of cerebral mantle to less than 1 cm in thickness was seen on computerized tomography (CT) scans of four animals sacrificed 1 to 2 months after kaolin treatment (preshunt group). Ventricular shunting resulted in successful recovery of the mantle on repeated CT scans obtained 1 to 2 months after shunting in seven animals (postshunt group). In the remaining 11 animals the cerebral mantle, which had been reduced to 4 mm in thickness prior to shunting, failed to recover even 2 months after the procedure (shunt-refractory group). On gross inspection, the preshunt specimens showed marked thinning of the white matter, with the cortical ribbon well preserved, while the postshunt specimens consisted predominantly of thickened white matter. Histopathological examination of the attenuated white matter of the preshunt specimens showed decreased nerve-fiber density, myelin destruction with myelin regeneration and/or repair of myelin sheaths, and reactive astrocytosis, which were prominent especially in the periventricular white matter. The main findings in the reconstituted white matter of the postshunt specimens were extensive myelin regeneration of residual axons and remarkable astroglial proliferation with mesenchymal reaction, particularly at capillaries. No clear evidence of increased numbers of nerve fibers or axonal regeneration was observed. The shunt-refractory specimens showed remarkable attenuation of cortex, in which reduced numbers of neurons and loss of cortical lamination were noted, with vestigial white matter. The results indicate that astroglial proliferation with mesenchymal reaction and myelin regeneration contribute to the reconstitution of the cerebral mantle volume following ventricular shunting in this model. It is suggested that the critical factor for mantle reconstitution in chronic hydrocephalus is whether cortex is preserved. PMID:1564546

Yamada, H; Yokota, A; Furuta, A; Horie, A

1992-05-01

60

21 CFR 874.3850 - Endolymphatic shunt tube with valve.  

Code of Federal Regulations, 2011 CFR

...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3850 Endolymphatic shunt tube with valve. (a) Identification. An endolymphatic shunt...

2011-04-01

61

21 CFR 874.3850 - Endolymphatic shunt tube with valve.  

Code of Federal Regulations, 2012 CFR

...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3850 Endolymphatic shunt tube with valve. (a) Identification. An endolymphatic shunt...

2012-04-01

62

Radionuclide demonstration of intrapulmonary shunting in cirrhosis  

SciTech Connect

The association of hepatic cirrhosis and severe arterial hypoxemia has been well described. Although alterations in ventilatory function may partially account for the hypoxemia, the principal mechanism is thought to be a microangiopathic change in the pulmonary vasculature resulting in intrapulmonary arteriovenous shunting with resultant systemic desaturation. Whole-body radionuclide scans with technetium-99m macroaggregated albumin labeling have been diagnostic of right-to-left shunting by their demonstration of tracer accumulation within the extrapulmonary circulation. A case of severe pulmonary arteriovenous shunting in an alcoholic patient in whom hepatic disease had not been of apparent clinical significance before radionuclide scanning is reported. He did not have cuntaeous angiomata as have all other patients with alcoholic cirrhosis and hypoxemia.

Bank, E.R.; Thrall, J.H.; Dantzker, D.R.

1983-05-01

63

Radionuclide demonstration of intrapulmonary shunting in cirrhosis  

SciTech Connect

The association of hepatic cirrhosis and severe arterial hypoxemia has been well described. Although alterations in ventilatory function may partially account for the hypoxemia, the principal mechanism is thought to be a microangiopathic change in the pulmonary arteriovenous shunting with resultant systemic desaturation. Whole-body radionuclide scans with technetium-99m macroaggrregated albumin (/sup 99m/Tc MAA) labeling have been diagnostic of right-to-left shunting by their demonstration of tracer accumulation within the extrapulmonary circulation. A case of severe pulmonary arteriovenous shunting in an alcoholic patient in whom hepatic disease had not been of apparent clinical significance before radionuclide scanning is reported. He did not have cutaneous angiomata as have all other patients with alcoholic cirrhosis and hypoxemia.

Bank, E.R.; Thrall, J.H.; Dantzker, D.R.

1983-05-01

64

[Radioisotopic methods for studying cerebrospinal fluid shunts].  

PubMed

The article presents a general and critical review of the radio-isotopic methods for assessing the function of the surgical shunts of cerebrospinal fluid (CSF). The radio-isotope cisternography may indirectly demonstrate the function of the shunt by the postoperative modification of the eventual ventricular reflux and of the permeability of the subarachnoid spaces on the cerebral convexity. The methods of direct ventricular injection of the indicator permit a more direct assessment of the drainage, as based on a scintigraphy, or on the quantitative study of the cephalic radio-activity, or on the demonstration of radio-activityon a target-organ. The direct injection of a highly diffusible indicator in the valve allows a quantitative measurement of the flow of CSF in the shunt and brings morphological arguments for the localization of the eventual occlusion. The technical aspects of the latter method are critically discussed and illustrated by personal results. PMID:796747

Depresseux, J C; Stevenaert, A

1976-01-01

65

Shunt malfunction after roller coaster ride  

Microsoft Academic Search

Introduction  We report a case of shunt malfunction after a child was subjected to G forces during a roller coaster ride.\\u000a \\u000a \\u000a \\u000a Discussion  The temporal sequence of events suggests proximal catheter obstruction with subsequent symptoms of raised intracranial pressure\\u000a immediately after experience with a G force ride. A shunt revision with catheter change led to resolution of symptoms, and\\u000a findings were consistent with

Christopher Gegg; Greg Olavarria; Jogi V. Pattisapu

2009-01-01

66

Morbidity and mortality after peritoneovenous shunt surgery for refractory ascites  

Microsoft Academic Search

A prospective analysis of the morbidity and mortality after peritoneovenous shunting was carried out in 25 patients who had a total of 27 shunts for refractory ascites. Major complications were limited to the patients in whom ascites was secondary to hepatic rather than peritoneal disease. Immediate postoperative complications followed 17 out of the 23 shunts carried out in patients with

D Rubinstein; I McInnes; F Dudley

1985-01-01

67

Recurrent Breast Cancer in a Patient with a Ventriculoperitoneal Shunt  

PubMed Central

We report a case of a patient with recurrent infiltrating ductal carcinoma of the breast encasing a ventriculoperitoneal shunt. We also review the current literature regarding reports of breast malignancy around a ventriculoperitoneal shunt, as well as the potential relevance of such shunts to the preoperative evaluation and management of patients with breast cancer. PMID:25648450

Copeland-Halperin, Libby R.; Cohen, Robert A.

2015-01-01

68

Functional gait comparison between children with myelomeningocele: shunt versus no shunt.  

PubMed

The aim of this study was to compare functional gait differences between patients with myelomeningocele (MM) who have a ventriculoperitoneal shunt (VPS) with those who do not. Our analyses were adjusted for confounding by age, lesion level, orthotic use, and assistive device use. The Functional Mobility Scale (FMS) was used to compare the shunted group (n=98; 60 males, 38 females; mean age 10y 2mo [SD 3y 11mo]; 73 sacral/19 low lumber/six high lumbar lesion level) with the non-shunted group (n=63; 32 males, 31 females; mean age 9y 11mo [SD 3y 11mo]; 45 sacral/12 low lumber/six high lumbar lesion level). Participants with a shunt had lower FMS 500 and FMS 50 scores compared with participants without a shunt; hence the participants without a shunt were more independent in their ambulation at medium and longer distances. For a subset of participants who underwent a three-dimensional gait analysis, we also collected temporal-spatial gait parameters (velocity, cadence, and stride length). Our results show that participants with MM and no shunt who underwent gait analysis(11 males, 10 females; mean age 9y 6mo [SD 4y]; 15 sacral/6 low lumber/0 high lumbar lesion level) tend to walk at a significantly greater velocity and stride length as compared with those with a shunt (33 males, 18 females; mean age 10y [SD 4y]; 38 sacral/13 low lumber/zero high lumbar lesion level). These data allow the treatment team to present more specific information regarding functional ambulatory expectations to patients with MM and their families. PMID:17880646

Battibugli, Simone; Gryfakis, Nicholas; Dias, Luciano; Kelp-Lenane, Claudia; Figlioli, Stephanie; Fitzgerald, Elizabeth; Hroma, Nicole; Seshadri, Roopa; Sullivan, Christine

2007-10-01

69

Shunting arc generation by parallel rod configuration  

NASA Astrophysics Data System (ADS)

Multi-shunting arc discharges were generated using carbon rods to deposit a carbon film on a silicon substrate. Two carbon rods of 2 mm diameter and 40 mm length were set between electrodes in parallel to generate multiple carbon plasmas. The pulse current was supplied from a 20 µF capacitor bank to evaporate the surface of the rods through a Joule heating process. Repetitive pulse voltages of -1 kV were applied to the disk electrode to extract the carbon ion from the plasmas and to deposit a carbon film. The rod current for both rods shows almost the same value before shunting arc ignition. The shunting arc was generated at 5-10 µs after the release of energy stored in the capacitor bank. The shunting arc current was controlled successfully by inserting an inductor in series to the rod. The ion current was changed by the position of the disk electrode owing to the difference in the arc current for each rod. The deposition rate of the carbon film on the silicon substrate also showed a difference with the position of the substrate. The spatial profile of the deposition rate was controlled by the inductance of each rod branch.

Takaki, T.; Murakami, T.; Mukaigawa, S.; Fujiwara, T.; Yukimura, K.

2011-02-01

70

Transjugular Intrahepatic Portosystemic Shunt: A Medical Perspective  

Microsoft Academic Search

The transjugular intrahepatic portosystemic shunt (TIPS) is an exciting new addition to the therapeutic armamentarium against portal hypertension. It is currently indicated for salvage of patients with active variceal hemorrhage despite sclerotherapy or where sclerotherapy is not feasible. Its use for recurrent episodes of bleeding despite chronic sclerotherapy and for ascites and hepatorenal syndrome remains experimental. It is contraindicated in

Arun J. Sanyal; Mitchell L. Shiffman

1995-01-01

71

Vibration isolation using a shunted electromagnetic transducer  

Microsoft Academic Search

By attaching an electromagnetic transducer to a mechanical isolation system and shunting the terminals of the transducer with electrical impedance, we can provide improved isolation performance while eliminating the need for an additional sensor. Simulated and experimental results on a simple electro-mechanical isolation system show that the proposed controller is capable of peak damping and high frequency attenuation.

Sam Behrens; Andrew J. Fleming; S. O. Reza Moheimani

2004-01-01

72

Vestibular neurectomy with simultaneous endolymphatic subarachnoid shunt  

Microsoft Academic Search

The purpose of this study was to assess the advantages of combined vestibular neurectomy (VN) and endolymphatic subarachnoid shunt (ELSS) surgeries in classic Menière's disease. We performed a retrospective analysis of the results of 116 patients with classic Menière's disease who were operated on via a posterior fossa approach. All patients underwent selective VN. In 86 of the patients, ELSS

Nebil Göksu; Yildirim A. Bayazit; Abdullah Abdulhalik; Yusuf K. Kemalo?lu

2002-01-01

73

[Transjugular intrahepatic portacaval shunt. Preliminary results].  

PubMed

Transjugular implantation of a metallic prosthesis between main portal branch and a hepatic vein is a new intrahepatic portosystemic shunt method to treat portal hypertension. Forty-nine cirrhotic patients with portal hypertension were treated using this technique. The success rate of implantation was 94%. Mortality due to the procedure was 2%. Early complications decreased with the operator's learning curve consisting of bleeding (20%): digestive hemorrhage (n = 5; 12%), hemobilia (n = 4; 8%), which ceased after withdrawal of post-operative heparin. Early thrombosis following shunt implantation occurred in 13% of the patients. Shunt implantation resulted in a 53 +/- 16% decrease in the portocaval pressure gradient (21 +/- 5 to 10 +/- 4 mmHg). Shunts were performed in 45 patients to prevent a recurrence of variceal bleeding. Follow-up of 41 patients showed 12.2% with variceal rebleeding and 16 patients (39%) with a stenosis requiring a redilation. Ascites improved in 95% of the patients and hepatic encephalopathy occurred in 17%. One year survival was 85%. Controlled studies are needed to determine the indications of this new treatment for ascites and bleeding. PMID:8243926

Perarnau, J M; Raabe, J J; Schwing, D; Rucin, B; Monchovet, S; Rössle, M; Arbogast, J

1993-01-01

74

Transjugular intrahepatic portosystemic shunts: an update.  

PubMed

Transjugular intrahepatic portosystemic shunts (TIPS) have been used in the treatment of complications of portal hypertension. TIPS is used for the control of acute variceal bleeding and for the prevention of vericeal rebleeding when pharmacologic therapy and endoscopic therapy have failed. Patients with refractory ascites with adequate hepatic reserve and renal function who fail to respond to large volume paracentesis may be reasonable candidates for TIPS. Promising indications for TIPS are Budd-Chiari syndrome uncontrolled by medical therapy, severe portal hypertensive gastropathy, refractory hepatic hydrothorax, and hepatorenal syndrome. TIPS cannot be recommended for preoperative portal decompression solely to facilitate liver transplantation. Special care should be taken to insure proper placement of the stent to avoid increasing the technical difficulty of the transplantation procedure. The major limiting factors for TIPS success are shunt dysfunction and hepatic encephalopathy. Because shunt stenosis is the most important cause of recurrent complications of portal hypertension, a surveillance program to monitor shunt patency is mandatory. The MELD score may be useful in predicting post-TIPS survival, and also in counseling patients and their families. PMID:12619016

Rosado, Barbara; Kamath, Patrick S

2003-03-01

75

The Delta Valve: a physiologic shunt system  

Microsoft Academic Search

PS Medical has advanced the state-of-the-art in hydrocephalus valve technology with the introduction of the Delta Valve. The Delta Valve is designed upon the premise that the shunted patient should have intracranial pressure (ICP) maintenance within a normal range regardless of cerebrospinal fluid (CSF) flow rate or body position. All previous valves have performance characteristics that are greatly influenced by

David A. Watson

1994-01-01

76

Passively Shunted Piezoelectric Damping of Centrifugally-Loaded Plates  

NASA Technical Reports Server (NTRS)

Researchers at NASA Glenn Research Center have been investigating shunted piezoelectric circuits as potential damping treatments for turbomachinery rotor blades. This effort seeks to determine the effects of centrifugal loading on passively-shunted piezoelectric - damped plates. Passive shunt circuit parameters are optimized for the plate's third bending mode. Tests are performed both non-spinning and in the Dynamic Spin Facility to verify the analysis, and to determine the effectiveness of the damping under centrifugal loading. Results show that a resistive shunt circuit will reduce resonant vibration for this configuration. However, a tuned shunt circuit will be required to achieve the desired damping level. The analysis and testing address several issues with passive shunt circuit implementation in a rotating system, including piezoelectric material integrity under centrifugal loading, shunt circuit implementation, and tip mode damping.

Duffy, Kirsten P.; Provenza, Andrew J.; Trudell, Jeffrey J.; Min, James B.

2009-01-01

77

Free floating ventricular shunt catheter between lateral ventricles: a case report of an unusual ventriculoperitoneal shunt complication.  

PubMed

Ventriculoperitoneal (VP) shunt proximal tip disconnection is rarely seen as a shunt complication. Shunt dysfunction and hydrocephaly can develop due to this disconnection. Presented here is a case of a disconnection of the ventricular catheter from the shunt valve, which passed between both lateral ventricles by free floating in the brain CT. The patient was operated on for hydrocephaly. The dysfunctional shunt valve and peritoneal catheter were removed and a new VP shunt system was implemented. Although some publications report that the ventricular catheter can be disconnected from the shunt valve, can adhere to the intraventricular structures, and can be a source of infection, no studies similar to the current case were found in the literature reporting a free floating ventricular catheter between the lateral ventricles. PMID:24310472

Erol, Fatih Serhat; Cakin, Hakan; Ozturk, Sait; Donmez, Osman; Kaplan, Metin

2013-01-01

78

Portacaval shunt in patients with familial hypercholesterolemia.  

PubMed Central

Portacaval shunt was performed in ten patients with homozygous and two with heterozygous familial hypercholesterolemia (FH). Total serum cholesterol was lowered by 20% to 55.4% during follow-up periods of 14 months to almost 9 years, with commensurate decreases in LDL cholesterol. The effect on HDL cholesterol and triglyceride levels was variable. Tendinocutaneous xanthomas diminished or disappeared. Growth and development in children proceeded or accelerated. There was no detectable emotional or intellectual deterioration. Hepatic failure did not occur, although blood ammonia concentrations and serum alkaline phosphatase levels increased relative to preoperative values. Cardiac symptoms were often improved, but evidence of reversal of cardiovascular lesions was inconclusive. Three patients with pre-existing heart disease died of cardiac complications after 4 months, 18 1/2 months, and 30 months. Portacaval shunt has been effective therapy for patients with FH who were refractory or intolerant to medical treatment; it should be performed before the development of irreversible cardiovascular damage. PMID:6615051

Starzl, T E; Chase, H P; Ahrens, E H; McNamara, D J; Bilheimer, D W; Schaefer, E J; Rey, J; Porter, K A; Stein, E; Francavilla, A; Benson, L N

1983-01-01

79

Liver cell adenomas and portosystemic shunt.  

PubMed

We report the case of a young man who developed multiple liver cell adenomas 13 years after a mesentericocaval shunt. Radiological findings did not provide diagnosis. Histological findings of two biopsied nodules were compatible with liver cell adenoma. Our patient had no known risk factors for liver cell adenomas. We discuss the hypothesis that disturbed hepatic vascularisation could promote the development of liver cell adenomas. PMID:18496891

Dhalluin-Venier, V; Fabre, M; Jacquemin, E; Rangheard, A-S; Pelletier, G; Buffet, C

2008-02-01

80

Programmable shunt-related suicide attempt  

Microsoft Academic Search

Summary  The treatment of hydrocephalus has benefited recently from the use of programmable shunt valves. These devices can be adjusted\\u000a using magnets to regulate how much spinal fluid is drained. However, it is unclear to what extent other environmental magnetic\\u000a sources can affect programmable valves. We present the case of a man who attempted suicide by successfully turning his adjustable\\u000a valve

S. G. Turner; W. A. Hall

2006-01-01

81

Active shunt capacitance cancelling oscillator circuit  

DOEpatents

An oscillator circuit is disclosed which can be used to produce oscillation using a piezoelectric crystal, with a frequency of oscillation being largely independent of any shunt capacitance associated with the crystal (i.e. due to electrodes on the surfaces of the crystal and due to packaging and wiring for the crystal). The oscillator circuit is based on a tuned gain stage which operates the crystal at a frequency, f, near a series resonance frequency, f.sub.S. The oscillator circuit further includes a compensation circuit that supplies all the ac current flow through the shunt resistance associated with the crystal so that this ac current need not be supplied by the tuned gain stage. The compensation circuit uses a current mirror to provide the ac current flow based on the current flow through a reference capacitor that is equivalent to the shunt capacitance associated with the crystal. The oscillator circuit has applications for driving piezoelectric crystals for sensing of viscous, fluid or solid media by detecting a change in the frequency of oscillation of the crystal and a resonator loss which occur from contact of an exposed surface of the crystal by the viscous, fluid or solid media.

Wessendorf, Kurt O.

2003-09-23

82

Incidence and risk factors of ventriculoperitoneal shunt infections in children: a study of 333 consecutive shunts in 6 years.  

PubMed

The major aims of this study were to estimate the infection rate and recognize the risk factor for ventriculoperitoneal (VP) shunt infections in children. To analyze shunt infection rate and identify risk factors, a retrospective cohort analysis of 333 consecutive VP shunt series was performed at Seoul National University Children's Hospital in Korea between January 2005 and February 2011. Overall, 35 shunts (10.5%) were infected, which represented an infection rate of 0.075 infection cases per shunt per year. VP shunt infection occurred at a median of 1 month (range, 6 days to 8 months) after insertion. An independent risk factor for shunt infection was undergoing an operation before the first year of life (relative risk 2.31; 95% confidence interval, 1.19-4.48). The most common causative microorganism was coagulase-negative staphylococci in 16 (45.7%) followed by Staphylococcus aureus in 8 (22.9%). Methicillin resistance rate was 83.3% among coagulase-negative staphylococci and S. aureus. In this study, cerebrospinal fluid shunt infection rate was 10.5%. Infection was frequently caused by methicillin-resistant coagulase-negative staphylococci and S. aureus within two months after shunt surgery. Vancomycin may be considered as the preoperative prophylaxis for shunt surgery in a situation where methicillin resistance rate is very high. PMID:23255859

Lee, Joon Kee; Seok, Joon Young; Lee, Joon Ho; Choi, Eun Hwa; Phi, Ji Hoon; Kim, Seung-Ki; Wang, Kyu-Chang; Lee, Hoan Jong

2012-12-01

83

Ventriculoperitoneal shunt infection following uterine instrumentation for dysfunctional uterine bleeding.  

PubMed

Shunt infections are most common within the first 6 months following implantation. A shunt infection 19 years after implantation secondary to uterine ablation has not been reported to our knowledge. Office hysteroscopic procedures have become commonplace in gynecologic practice. Infectious complication rates are low, but peritonitis has been described. We present a patient with a ventriculoperitoneal shunt infection following a uterine ablation for dysfunctional uterine bleeding. Three days following the ablation she developed abdominal pain. CT scan of the abdomen 5 months after the procedure revealed a pseudocyst. She then underwent removal of her shunt with intra-operative cultures revealing Streptococcus agalactiae. Definitive treatment consisted of shunt explantation and antibiotic treatment with complete resolution of her pain and pseudocyst. Consideration for prophylactic antibiotics should be made when a patient with a ventriculoperitoneal shunt undergoes any transvaginal procedure. PMID:24656752

Shaw, Andrew B; Marlin, Evan S; Ikeda, Daniel S; Ammirati, Mario

2014-08-01

84

Factors affecting ventriculoperitoneal shunt survival in adult patients  

PubMed Central

Background: Ventriculoperitoneal (VP) shunt insertion remains the mainstay of treatment for hydrocephalus despite a high rate of complications. The predictors of shunt malfunction have been studied mostly in pediatric patients. In this study, we report our 11-year experience with VP shunts in adult patients with hydrocephalus. We also assess the various factors affecting shunt survival in a developing country setting. Methods: A retrospective chart analysis was conducted for all adult patients who had undergone shunt placement between the years 2001 and 2011. Kaplan–Meier curves were used to determine the duration from shunt placement to first malfunction and log-rank (Cox–Mantel) tests were used to determine the factors affecting shunt survival. Results: A total of 227 patients aged 18–85 years (mean: 45.8 years) were included in the study. The top four etiologies of hydrocephalus included post-cranial surgery (23.3%), brain tumor or cyst (22.9%), normal pressure hydrocephalus (15%), and intracranial hemorrhage (13.7%). The overall incidence of shunt malfunction was 15.4% with the median time to first shunt failure being 120 days. Etiology of hydrocephalus (P = 0.030) had a significant association with the development of shunt malfunction. Early shunt failure was associated with age (P < 0.001), duration of hospital stay (P < 0.001), Glasgow Coma Scale (GCS) score less than 13 (P = 0.010), excision of brain tumors (P = 0.008), and placement of extra-ventricular drains (P = 0.033). Conclusions: Patients with increased age, prolonged hospital stay, GCS score of less than 13, extra-ventricular drains in situ, or excision of brain tumors were more likely to experience early shunt malfunction. PMID:25722930

Khan, Farid; Rehman, Abdul; Shamim, Muhammad S.; Bari, Muhammad E.

2015-01-01

85

Delayed incidental diagnosis of postoperative extradural hematoma following ventriculoperitoneal shunt  

PubMed Central

Ventriculo peritoneal (VP) shunt uncommonly complicates as intracranial hematomas which can still occur in patients with a functioning VP shunt leading to a delay in the diagnosis which can be extremely dangerous and lead to adverse outcomes. We report a case of an incidental diagnosis of delayed post-operative EDH following VP shunt in an young adult patient with a right cerebellar lesion and highlight the need for meticulous post-operative neurological examination. PMID:25552861

Byrappa, Vinay; Redhu, Shruti; Varadarajan, Bhadrinarayan

2015-01-01

86

Superconducting fault current-limiter with variable shunt impedance  

DOEpatents

A superconducting fault current-limiter is provided, including a superconducting element configured to resistively or inductively limit a fault current, and one or more variable-impedance shunts electrically coupled in parallel with the superconducting element. The variable-impedance shunt(s) is configured to present a first impedance during a superconducting state of the superconducting element and a second impedance during a normal resistive state of the superconducting element. The superconducting element transitions from the superconducting state to the normal resistive state responsive to the fault current, and responsive thereto, the variable-impedance shunt(s) transitions from the first to the second impedance. The second impedance of the variable-impedance shunt(s) is a lower impedance than the first impedance, which facilitates current flow through the variable-impedance shunt(s) during a recovery transition of the superconducting element from the normal resistive state to the superconducting state, and thus, facilitates recovery of the superconducting element under load.

Llambes, Juan Carlos H; Xiong, Xuming

2013-11-19

87

Semi-shunt field emission in electronic devices  

SciTech Connect

We introduce a concept of semi-shunts representing needle shaped metallic protrusions shorter than the distance between a device electrodes. Due to the lightening rod type of field enhancement, they induce strong electron emission. We consider the corresponding signature effects in photovoltaic applications; they are: low open circuit voltages and exponentially strong random device leakiness. Comparing the proposed theory with our data for CdTe based solar cells, we conclude that stress can stimulate semi-shunts' growth making them shunting failure precursors. In the meantime, controllable semi-shunts can play a positive role mitigating the back field effects in photovoltaics.

Karpov, V. G., E-mail: victor.karpov@utoledo.edu [Department of Physics and Astronomy, University of Toledo, Toledo, Ohio 43606 (United States); Shvydka, Diana, E-mail: diana.shvydka@utoledo.edu [Department of Radiation Oncology, University of Toledo, Toledo, Ohio 43606 (United States)

2014-08-04

88

21 CFR 882.5550 - Central nervous system fluid shunt and components.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 false Central nervous system fluid shunt and components. 882.5550...882.5550 Central nervous system fluid shunt and components. (a) Identification. A central nervous system fluid shunt is a device or combination...

2014-04-01

89

21 CFR 882.5550 - Central nervous system fluid shunt and components.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false Central nervous system fluid shunt and components. 882.5550...882.5550 Central nervous system fluid shunt and components. (a) Identification. A central nervous system fluid shunt is a device or combination...

2011-04-01

90

21 CFR 882.5550 - Central nervous system fluid shunt and components.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Central nervous system fluid shunt and components. 882.5550...882.5550 Central nervous system fluid shunt and components. (a) Identification. A central nervous system fluid shunt is a device or combination...

2013-04-01

91

21 CFR 882.5550 - Central nervous system fluid shunt and components.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Central nervous system fluid shunt and components. 882.5550...882.5550 Central nervous system fluid shunt and components. (a) Identification. A central nervous system fluid shunt is a device or combination...

2012-04-01

92

21 CFR 882.5550 - Central nervous system fluid shunt and components.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Central nervous system fluid shunt and components. 882.5550...882.5550 Central nervous system fluid shunt and components. (a) Identification. A central nervous system fluid shunt is a device or combination...

2010-04-01

93

Does the shunt opening pressure influence the effect of shunt surgery in normal pressure hydrocephalus?  

Microsoft Academic Search

Summary Thirteen patients with normal pressure hydrocephalus were operated upon with an externally manoeuvrable shunt system (Sophy SU8) in order to investigate its influence on clinical outcome, intracranial pressure and cranial CT parameters. The opening pressure was set at high at surgery and lowered stepwise at intervals of three months to medium and low. The clinical condition, intracranial pressure and

A. Larsson; Ch. Jensen; M. Bilting; S. Ekholm; H. Stephensen; C. Wikkelsö

1992-01-01

94

Scientific heritage of L.P. Shilnikov  

NASA Astrophysics Data System (ADS)

This is the first part of a review of the scientific works of L.P. Shilnikov. We group his papers according to 7 major research topics: bifurcations of homoclinic loops; the loop of a saddle-focus and spiral chaos; Poincare homoclinics to periodic orbits and invariant tori, homoclinic in noautonous and infinite-dimensional systems; Homoclinic tangency; Saddlenode bifurcation — quasiperiodicity-to-chaos transition, blue-sky catastrophe; Lorenz attractor; Hamiltonian dynamics. The first two topics are covered in this part. The review will be continued in the further issues of the journal.

Afraimovich, Valentin S.; Gonchenko, Sergey V.; Lerman, Lev M.; Shilnikov, Andrey L.; Turaev, Dmitry V.

2014-07-01

95

Emergency portasystemic shunting in cirrhotics with bleeding varices--a comparison of portacaval and mesocaval shunts.  

PubMed

Despite the best conservative measures available for the control of major variceal hemorrhage, some patients either continue to bleed, or rebleed early, and require emergency surgery. One hundred patients with cirrhosis and uncontrolled bleeding were treated with emergency portasystemic shunts between 1968 and 1983. Fifty eight patients had end-to-side portacaval shunts and 42 had Dacron interposition mesocaval shunts. Both groups were comparable with respect to age, sex and prevalence of alcoholism. There was an increased severity of liver disease as assessed by Child's class in the mesocaval group of patients. Overall in-hospital mortality was 31% with no significant difference demonstrated between the mesocaval group (28%) and the portacaval group (33%), nor between alcoholic cirrhotics (34%) and non-alcoholic cirrhotics (21%). Mortality rates based on severity of liver disease were: Child's A (1/6) 17%, Child's B (9/48) 19%, and Child's C (21/46) 46%. There was a statistically significant difference between Child's A & B and Child's C (p less than 0.01). Four patients were lost to follow-up. No significant differences were found in 5 year survival by life table analysis comparing portacaval (39%) vs. mesocaval (28%) groups or alcoholic cirrhotics (36%) vs. non-alcoholic cirrhotics (29%). Encephalopathy in survivors was absent in 46%, mild in 28% and severe in 26% of patients. There was no significant difference in encephalopathy rates following portacaval or mesocaval shunting. Neither operation was clearly superior and choice of operation can be made on the basis of technical and anatomical factors and surgeon experience. Emergency shunting remains a useful option for patients with variceal bleeding refractory to other more conservative therapy, and is associated with acceptable early mortality and long term survival rates. PMID:2487058

Soutter, D I; Langer, B; Taylor, B R; Greig, P

1989-04-01

96

On the feedback structure of wideband piezoelectric shunt damping systems  

Microsoft Academic Search

This paper studies the feedback structure associated with piezoelectric shunt damping systems and introduces a new impedance structure for multi-mode piezoelectric shunt damping. The impedance is shown to be realizable using passive circuit components and digital implementation of the associated admittance transfer function is discussed.

S. O. Reza Moheimani; Andrew J. Fleming; Sam Behrens

2003-01-01

97

Shunt current loss of the vanadium redox flow battery  

Microsoft Academic Search

The shunt current loss is one of main factors to affect the performance of the vanadium redox flow battery, which will shorten the cycle life and decrease the energy transfer efficiency. In this paper, a stack-level model based on the circuit analog method is proposed to research the shunt current loss of the vanadium redox flow battery, in which the

Feng Xing; Huamin Zhang; Xiangkun Ma

2011-01-01

98

Ventriculosubgaleal Shunts for Posthemorrhagic Hydrocephalus in Premature Infants  

Microsoft Academic Search

Objective: The early management of posthemorrhagic hydrocephalus in premature infants is challenging and controversial. These infants need a temporary cerebrospinal fluid (CSF) diversion procedure until they gain adequate weight, and the blood and protein levels in CSF are reasonably low before permanent shunt can be placed. Various options are available with their associated advantages and disadvantages. Ventriculosubgaleal shunts have been

Brian K. Willis; Cherukuri Ravi Kumar; Esther L. Wylen; Anil Nanda

2005-01-01

99

Structural multi-modal damping by optimizing shunted piezoelectric transducers  

Microsoft Academic Search

The capacity of different auto-supplied devices using shunted piezoelectric circuits are studied here to improve structural damping by avoiding implementation of complex and heavy control devices. The presented technique uses a dedicated numerical piezo-mechanical model combining both mechanical and electrical coupling parameters. An original methodology are also introduced for optimizing the parameters of electrical shunt circuits connected to piezoelectric elements

Stéphanie Livet; Manuel Collet; Marc Berthillier; Pierrick Jean; Jean-Marc Cote

2011-01-01

100

Shunting passenger trains: getting ready for Marjan van den Akker  

E-print Network

on the platform. During rush hours almost all train units available are required to transport passengers and, thus Management 1 #12;needed for transporting passengers. Thus, train units may have to be parked at a shunt yardShunting passenger trains: getting ready for departure Marjan van den Akker Hilbrandt Baarsma

Utrecht, Universiteit

101

Shunting of Passenger Train Units in a Railway Station  

Microsoft Academic Search

In this paper we introduce the problem of shunting passenger train units in a railway station. Shunting occurs whenever train units are temporarily not necessary to operate a given timetable. We discuss several aspects of this problem and focus on two subproblems. We propose mathematical models for these subproblems together with a solution method based on column generation. Furthermore, a

Richard Freling; Ramon M. Lentink; Leo G. Kroon; Dennis Huisman

2005-01-01

102

Portacaval shunt in a calf: Clinical, pathologic, and ultrasonographic findings  

PubMed Central

A calf with a previous history of lameness was presented for weakness and anorexia. Increased liver enzymes and difficulty in assessing the portal system by ultrasonography were compatible with liver disease. Doppler ultrasonography revealed an extrahepatic portacaval shunt. This is the first ultrasonographic description of extra-hepatic portacaval shunt in a ruminant. PMID:17494368

Buczinski, Sébastien; Duval, Julie; d’Anjou, Marc-André; Francoz, David; Fecteau, Gilles

2007-01-01

103

Lithium in LP 944-20  

E-print Network

We present a new estimate of the lithium abundance in the atmosphere of the brown dwarf LP 944-20. Our analysis is based on a self-consistent analysis of low, intermediate and high resolution optical and near-infrared spectra. We obtain log N(Li) = 3.25 +/-0.25 using fits of our synthetic spectra to the Li I resonance line doublet profiles observed with VLT/UVES and AAT/SPIRAL. This lithium abundance is over two orders of magnitude larger than previous estimates in the literature. In order to obtain good fits of the resonance lines of K I and Rb I and better fits to the TiO molecular absorption around the Li I resonance line, we invoke a semi-empirical model atmosphere with the dusty clouds located above the photosphere. The lithium abundance, however, is not changed by the effects of the dusty clouds. We discuss the implications of our estimate of the lithium abundance in LP 944-20 for the understanding of the properties of this benchmark brown dwarf.

Ya. V. Pavlenko; H. R. A. Jones; E. L. Martin; E. Guenther; M. A. Kenworthy; M. R. Zapatero Osorio

2007-07-14

104

Long-term results of shunt procedures for tricuspid atresia.  

PubMed

One hundred forty-eight infants and children with tricuspid atresia treated by one or more operations during a 31-year period were reviewed to indicate the long-term results of shunt procedures. In general, the Potts shunt was used most frequently in small infants while the Blalock anastomosis was preferred for children older than 3 to 6 months. The Glenn anastomosis appears to be a good secondary shunt but its use depends on specific anatomical features and the possibility of doing a Fontan procedure in the future. The duration of effective palliation for each shunt has been examined actuarilly by life-table analysis. It is essential that shunts not only maintain adequate oxygen saturation but also preserve the patency, size, and shape of the pulmonary arteries and normal pulmonary vascular resistance. PMID:7362322

Trusler, G A; Williams, W G

1980-04-01

105

Neonatal Blalock-Taussig shunt: technical aspects and postoperative management.  

PubMed

A systemic-pulmonary artery shunt in neonates with decreased pulmonary blood flow is technically demanding. We describe our surgical technique, postoperative management, and results in 19 neonates who underwent a modified Blalock-Taussig shunt between April 2003 and March 2006. Prostaglandin infusion was required in 8 patients who were critically cyanosed, and 5 were on inotropic support preoperatively. A 3.5 or 4.0-mm polytetrafluoroethylene graft was anastomosed with 8/0 polypropylene suture. Postoperatively, systemic pressure was kept slightly higher than normal, and heparin was started early. One patient required revision of the shunt, and one was reexplored for bleeding. There were 2 hospital deaths (mortality, 11%) in patients with preoperative hemodynamic instability. The mean follow-up period was 12 months, with no late postoperative shunt blockage or death. Meticulous surgical technique and judicious use of heparin and inotropic agents improved the outcome and reduced the incidence of shunt blockage and reexploration for bleeding. PMID:18245697

Swain, Sunil K; Dharmapuram, Anil K; Reddy, Pramod; Ramdoss, Nagarajan; Raghavan, Sreekanth S; Kona, Samba M

2008-01-01

106

Repeated cannulation of umbilical hernia with Ventriculoperiotoneal shunt catheter  

PubMed Central

Ventriculoperitoneal (VP) shunts are commonly used to manage hydrocephalus in both adult and paediatric populations. Whilst infection remains by far the most common complication leading to shunt revision other causes need to be considered. Our case report examines a 62-year-old female who presents for operative management of a Choroid Plexus Papilloma. Post-operatively she develops hydrocephalus and is managed with a VP shunt. Interestingly the distal end of the catheter cannulated an unknown umbilical hernia twice creating diagnostic dilemma. Issues around shunt insertion in the morbidly obese population and the basic science behind cerebrospinal fluid reabsorption are explored. Although this is a rare complication it should be considered in any post-operative shunt patient is slow to recover particularly if they are obese. PMID:24903026

Laidlaw, R.S.; Little, N.

2014-01-01

107

Vancomycin for Treating Cerebrospinal Fluid Shunt Infections in Pediatric Patients  

PubMed Central

Infection is a major cause of CSF shunt failure that places the patient at risk of intellectual impairment, development of loculated CSF compartments, and death. The purpose of this article is to review the published literature related to vancomycin for treatment of pediatric CSF shunt infections. Fifty percent of shunt infections appear within 2 months of shunt placement or revision; 90% occur within 6 months. Ninety percent of organisms infecting CSF shunting devices are Staphylococcus and Streptococcus species. The emergence of methicillin-resistant strains of staphylococci has made vancomycin the antibiotic of choice for these infections. The usual intravenous regimen is 60 mg/kg/day divided every 6 hours. Intraventricular vancomycin should be considered for most patients, starting with 10 mg daily. CSF vancomycin concentrations should be monitored and dosing adjustments made as needed to maintain CSF trough vancomycin concentrations between 5 and 20 mg/L. PMID:23118622

Thompson, Jill B.; Einhaus, Stephanie; Buckingham, Steve; Phelps, Stephanie J.

2005-01-01

108

Fabrication and characterization of shunted ?-SQUID  

SciTech Connect

In order to eliminate hysteresis, we have fabricated and characterized niobium based shunted micron size superconducting quantum interference devices (?-SQUIDs). We find a wide temperature range where these ?-SQUIDs are non-hysteretic in nature and show a very good I{sub c} vs. B oscillations in hysteretic regime and V vs. B oscillations in non-hysteretic regime. Here we report the characteristics of a shunted- ?-SQUID (Wf38LS72D5). In this device we have achieved a large voltage modulation, in non-hysteretic regime, at various temperatures including such as 1.1 mV at 6.62 K with a transfer function V{sub ?}?=?7.2mV/?{sub 0}. The figures within the original article PDF file, as supplied to AIP Publishing, were affected by a PDF-processing error. Consequently, the article re-flowed and pagination increased from 3 to 4 pages. This article was updated on 14 May 2014 to correct the PDF-processing error, with the scientific content remaining unchanged. Readers are advised that the replacement article PDF file contains an additional blank page to preserve the original pagination.

Kumar, Nikhil, E-mail: knikhil@iitk.ac.in [Department of Physics, Indian Institute of Technology Kanpur - 208016 (India); Fournier, T.; Courtois, H.; Gupta, Anjan K. [Institute Neel, CNRS and Université Joseph Fourier, 25 Avenue des Martyrs, BP 166, 38042, Grenoble (France)

2014-04-24

109

Vibration control via shunted embedded piezoelectric fibers  

NASA Astrophysics Data System (ADS)

The scientific community has put significant efforts into the manufacturing of sensors and actuators made of piezoceramic fibers with interdigitated electrodes. These allow for increased conformability, integrability in laminate structures and offer high coupling factors. They are of particular interest for damping applications. This paper presents a comparison between piezoceramic monolithic actuators and Active Fiber Composites (AFCs) for shunt damping. For this purpose, the different actuators were bonded on aluminum cantilever plates, respectively embedded in a glass fiber composite cantilever plate. The vibration suppression was attained by converting the electric charge by means of the converse piezoelectric effect and dissipated through robust resonant shunt circuits. A new circuit topology was used, which enables efficient damping even with low piezoelectric capacitance. An integrated FE model was implemented for prediction of the natural frequencies, the optimum values for the electric components and the resulting damping performance. Patches working in the direct 3-3 mode show much better specific damping performance than the 3-1 actuated patch. The comparison between monolithic and AFC actuators shows that AFCs fulfill integrability and performance requirements for the planned damping applications.

Belloli, Alberto; Niederberger, Dominik; Kornmann, Xavier; Ermanni, Paolo; Morari, Manfred; Pietrzko, Stanislaw

2004-07-01

110

THE Lp VERSION OF NEWMAN'S INEQUALITY FOR LACUNARY POLYNOMIALS  

E-print Network

THE Lp VERSION OF NEWMAN'S INEQUALITY FOR LACUNARY POLYNOMIALS Peter Borwein and Tam´as Erd of Mn() are called M¨untz (or lacunary) polynomials. We first present a simplified version of Newman appearing in Newman's paper [5]. But more importantly, this modification allows us to prove the Lp analogues

Erdélyi, Tamás

111

LP and QP based learning from empirical data  

Microsoft Academic Search

The quadratic programming (QP) and the linear programming (LP) based method are recently the most popular methods for learning from empirical data (observations, samples, examples, records). Support vector machines (SVMs) are the newest models based on the QP algorithm in solving nonlinear regression and classification problems. The LP based learning also controls both the number of basis functions in a

Vojislav Kecman; Tim Arthanari; Ivana Hadzic

2001-01-01

112

pos(LP;M fl ) (;) ` T 1 pos(LP;M ff ) (;) by Claim 52. Moreover, as M fl is pre  

E-print Network

T 1 pos(LP;M fl ) (;) ` T 1 pos(LP;M ff ) (;) by Claim 52. Moreover, as M fl is pre­ founded, M + fl = T 1 pos(LP;M fl ) (;); so M + fl ` T 1 pos(LP;M ff ) (;). Consider now any element A 2 M + ff . Since M + ff = TLP (M fl ), there exists a rule r 2 ground(LP) such that H(r) = A and G(r) ` M fl

Zaniolo, Carlo

113

75 FR 8322 - EPIC Merchant Energy NJ/PA, LP, SESCO Enterprises, LLC, Coaltrain Energy, LP, Complainants, v...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Energy Regulatory Commission [Docket No. EL10-40-000] EPIC Merchant Energy NJ/PA, LP, SESCO Enterprises, LLC, Coaltrain...Rules of Practice and Procedure, 18 CFR 385.206 (2009), EPIC Merchant Energy NJ/PA, LP, SESCO Enterprises, LLC,...

2010-02-24

114

Laparoscopy for ventriculoperitoneal shunt implantation and revision surgery  

PubMed Central

Ventriculoperitoneal shunting (VPS) is a widely accepted technique for the treatment of hydrocephalus. The probability of shunt dysfunction is pretty high throughout life. Laparoscopy has become a valuable tool to perform VPS and treat abdominal complications. An electronic literature search was performed to reveal the published data relating laparoscopy and ventriculoperitoneal shunt in Medline, Embase, Scielo and Lilacs databases. The keywords employed were “laparoscopy” OR “laparoscopic surgery” AND “ventriculoperitoneal shunt” OR “shunt” AND “surgery” OR “implantation” OR “revision” OR “complication”. No high quality trials were developed comparing conventional laparotomic incision vs laparoscopic approach. Both approaches have evolved and currently there are less invasive options for laparotomy, like periumbilical small incisions; and for laparoscopy, like smaller and less incisions. Operating room time, blood loss and hospital stay may be potentially smaller in laparoscopic surgery and complications are probably the same as laparotomy. In revision surgery for abdominal complications after VPS, visualization of whole abdominal cavity is fundamental to address properly the problem and laparoscopic approach is valuable once it is safe, fast and much less invasive than laparotomy. Ventriculoperitoneal shunting is a widely accepted technique for the treatment of hydrocephalus. Laparoscopy assisted shunt surgery in selected cases might be a less invasive and more effective option for intrabdominal manipulation. The laparoscopic approach allows a better catheter positioning, lysis of fibrotic bundles and peritoneal inspection as well, without any additional complication. PMID:25228943

Pinto, Fernando Campos Gomes; de Oliveira, Matheus Fernandes

2014-01-01

115

Urokinase in the treatment of shunt malfunctions caused by thrombus.  

PubMed

Thrombus is a frequent cause of shunt malfunction both of the proximal end following intraventricular hemorrhage and of the distal catheter of a vascular shunt. Continued blockages may result in numerous shunt revisions until the blood has been cleared. We have treated 3 children with shunt malfunctions secondary to thrombus with urokinase, a thrombolytic agent. Two children had intraventricular hemorrhage following a shunt revision and were treated with intrashunt urokinase, and 1 with occlusion of an atrial catheter was treated with both intrashunt and systemic urokinase. All were symptomatic at the time of treatment (headaches, vomiting, full fontanel, somnolence) and all had ventriculomegaly demonstrated on computed tomography. Various dosage regimens were used with total intrashunt doses of 20,000, 50,000, and 70,000 IU. All improved clinically, computed tomography scans demonstrated improvement, and all were discharged from the hospital. There were no complications of the urokinase administration. The 2 children with proximal occlusion have not required further shunt revisions at 12 and 27 months following treatment. The infant with atrial end occlusion subsequently underwent two proximal revisions with eventual removal of the atrial catheter because of infection. We conclude the intrashunt urokinase can be of value in the treatment of shunts by blood and blood products. PMID:9348152

Hudgins, R J; Boydston, W R; Gilreath, C L

1996-12-01

116

Quantum L_p and Orlicz spaces  

E-print Network

Let $\\A$ ($\\cM$) be a $C^*$-algebra (a von Neumann algebra respectively). By a quantum dynamical system we shall understand the pair $({\\A}, T)$ ($({\\cM}, T)$) where $T : {\\A} \\to {\\A}$ ($T : {\\cM} \\to {\\cM}$) is a linear, positive (normal respectively), and identity preserving map. In our lecture, we discuss how the techniques of quantum Orlicz spaces may be used to study quantum dynamical systems. To this end, we firstly give a brief exposition of the theory of quantum dynamical systems in quantum $L_p$ spaces. Secondly, we describe the Banach space approach to quantization of classical Orlicz spaces. We will discuss the necessity of the generalization of $L_p$-space techniques. Some emphasis will be put on the construction of non-commutative Orlicz spaces. The question of lifting dynamical systems defined on von Neumann algebra to a dynamical system defined in terms of quantum Orlicz space will be discussed.

L. E. Labuschagne; W. A. Majewski

2009-02-25

117

Baseline Neuropsychological Profile and Cognitive Response to Cerebrospinal Fluid Shunting for Idiopathic Normal Pressure Hydrocephalus  

Microsoft Academic Search

Objective: To evaluate neurocognitive changes and predict neurocognitive outcome after ventriculoperitoneal shunting for idiopathic normal pressure hydrocephalus (INPH). Background: Reports of neurocognitive response to shunting have been variable and studies that predict cognitive outcomes after shunting are limited. We reviewed our experience with cognitive outcomes for INPH patients who were selected for shunting based on abnormal cerebrospinal fluid (CSF) pressure

George Thomas; Matthew J. McGirt; Graeme Woodworth; Jennifer Heidler; Daniele Rigamonti; Argye E. Hillis; Michael A. Williams

2005-01-01

118

Current status of transjugular intrahepatic portosystemic shunts.  

PubMed Central

The use of the transjugular intrahepatic portosystemic shunt (TIPS) has emerged as an important nonoperative modality for variceal bleeding, intractable ascites, and for selected cases of hepatic venous obstruction. We believe that TIPS should be viewed as a 'bridge' to liver transplantation and should be carried out only in experienced centres. The adverse haemodynamic changes on the cardiopulmonary system after TIPS should be borne in mind. Prospective trials to evaluate the role of TIPS versus sclerotherapy in variceal bleeding will be watched with interest. There is, however, an urgent need to improve long-term results of TIPS as stent thrombosis and stenosis occur frequently. We advocate routine surveillance to detect these problems at an early stage. PMID:10320885

Patel, N. H.; Chalasani, N.; Jindal, R. M.

1998-01-01

119

Ion beam sputter-etched ventricular catheter for hydrocephalus shunt  

NASA Technical Reports Server (NTRS)

A cerebrospinal fluid shunt in the form of a ventricular catheter for controlling the condition of hydrocephalus by relieving the excessive cerebrospinal fluid pressure is described. A method for fabrication of the catheter and shunting the cerebral fluid from the cerebral ventricles to other areas of the body is also considered. Shunt flow failure occurs if the ventricle collapse due to improper valve function causing overdrainage. The ventricular catheter comprises a multiplicity of inlet microtubules. Each microtubule has both a large openings at its inlet end and a multiplicity of microscopic openings along its lateral surfaces.

Banks, B. A. (inventor)

1983-01-01

120

Transient ventriculoperitoneal shunt malfunction after chronic constipation: case report and review of literature  

Microsoft Academic Search

Background  Significant constipation in patients with shunt-dependent hydrocephalus may often be enough to bring a subclinical shunt malfunction\\u000a to clinical attention or even to be the cause of temporary distal peritoneal shunt malfunction. The treatment of the constipation\\u000a may address the symptomatic shunt dysfunction so as to avoid operative intervention. The pathogenesis of distal shunt malfunction\\u000a and its management in such

Dattatraya Muzumdar; Enrique C. G. Ventureyra

2007-01-01

121

Analytic approximation of matrix functions in $L^p$  

Microsoft Academic Search

We consider the problem of approximation of matrix functions of class $L^p$ on the unit circle by matrix functions analytic in the unit disk in the norm of $L^p$, $2\\\\le p<\\\\be$. For an $m\\\\times n$ matrix function $\\\\Phi$ in $L^p$, we consider the Hankel operator $H_\\\\Phi:H^q(C^n)\\\\to H^2_-(C^m)$, $1\\/p+1\\/q=1\\/2$. It turns out that the space of $m\\\\times n$ matrix functions in

L. Baratchart; F. L. Nazarov; V. V. Peller

2008-01-01

122

Emergency Portacaval Shunt Versus Rescue Portacaval Shunt in a Randomized Controlled Trial of Emergency Treatment of Acutely Bleeding Esophageal Varices in Cirrhosis—Part 3  

E-print Network

and treatment of gastrointestinal bleeding secondary tofor upper gastrointestinal bleeding; (5) number of hospitalBleeding esophageal varices EST Endoscopic sclerotherapy EPCS Emergency portacaval shunt PCS Portacaval shunt UGI Upper gastrointestinal

2010-01-01

123

8. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

8. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL LOCOMOTIVE NO. 6734 ON TURNTABLE, adjacent to Erecting Shop and Machine Shop - Juniata Shops, Turntable, South of Sixth Street at Third Avemue, Altoona, Blair County, PA

124

7. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL LOCOMOTIVE NO. 6734 ON TURNTABLE, adjacent to Erecting Shop and Machine Shop - Juniata Shops, Turntable, South of Sixth Street at Third Avemue, Altoona, Blair County, PA

125

4. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

4. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL LOCOMOTIVE NO. 6734 ON TURNTABLE, adjacent to Erecting Shop and Machine Shop - Juniata Shops, Turntable, South of Sixth Street at Third Avemue, Altoona, Blair County, PA

126

6. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL LOCOMOTIVE NO. 6734 ON TURNTABLE, adjacent to Erecting Shop and Machine Shop - Juniata Shops, Turntable, South of Sixth Street at Third Avemue, Altoona, Blair County, PA

127

5. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL LOCOMOTIVE NO. 6734 ON TURNTABLE, adjacent to Erecting Shop and Machine Shop - Juniata Shops, Turntable, South of Sixth Street at Third Avemue, Altoona, Blair County, PA

128

9. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

9. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL LOCOMOTIVE NO. 6734 ON TURNTABLE, adjacent to Erecting Shop and Machine Shop - Juniata Shops, Turntable, South of Sixth Street at Third Avemue, Altoona, Blair County, PA

129

Portosystemic Myelopathy: A Rare Neurological Presentation of Portosystemic Shunts  

PubMed Central

Portosystemic myelopathy is an unusual complication in patients with chronic liver disease with hepatic encephalopathy and portosystemic shunts. Here we present a case of 35-year-old male patient who presented to us with difficulty in walking and progressive stiffness in both lower limbs for two months. He had undergone splenectomy with distal splenorenal shunt 20 years back. On physical examination, he had spasticity in both lower limbs of grade 3, with minimal pyramidal weakness in lower limbs, brisk knee and ankle jerks. The plantar response was extensor. Upper limb examination was normal. On investigations, he had hypoalbuminemia, hyperbilirubinemia, increased plasma ammonia levels. Contrast enhanced CT scan abdomen revealed dilated splenorenal shunt and MRI spine showed no spinal cord compression. Electromyoneurogram was also normal. Spastic paraparesis due to portosystemic shunts was diagnosed. Liver transplantation can reverse the myelopathy only in earlier stages, hence early and accurate diagnosis is important.

Rao, Prasanna K.S.; Sheth, Keyur A.; Nadig, Raghunandan; Patil, Mallikarjun; Channagiri, Adarsh K.

2012-01-01

130

Should transjugular intrahepatic portosystemic shunt stent grafts be underdilated?  

PubMed

Although underdilation of transjugular intrahepatic portosystemic shunt (TIPS) stent grafts is commonly performed to limit complications arising from excessive portosystemic shunting, it is uncertain whether underdilated stents retain their smaller diameter indefinitely or eventually expand to nominal caliber. In this investigation, postprocedure computed tomography (CT) was used to compare diameters of underdilated TIPSs and TIPSs expanded to a nominal diameter of 10 mm in 61 cases. The groups had comparable shunt diameters on post-TIPS imaging (9.8 mm vs 9.9 mm; P = .079), with similar incidences of hepatic encephalopathy (34% vs 20%; P = .372), indicating stent self-expansion over time, and bringing into question the advantages of underdilation for customization of shunt caliber. PMID:25735521

Gaba, Ron C; Parvinian, Ahmad; Minocha, Jeet; Casadaban, Leigh C; Knuttinen, M Grace; Ray, Charles E; Bui, James T

2015-03-01

131

21 CFR 876.5955 - Peritoneo-venous shunt.  

Code of Federal Regulations, 2011 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5955 Peritoneo-venous shunt. (a) Identification. A...

2011-04-01

132

21 CFR 876.5955 - Peritoneo-venous shunt.  

Code of Federal Regulations, 2012 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5955 Peritoneo-venous shunt. (a) Identification. A...

2012-04-01

133

21 CFR 876.5955 - Peritoneo-venous shunt.  

Code of Federal Regulations, 2010 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5955 Peritoneo-venous shunt. (a) Identification. A...

2010-04-01

134

21 CFR 876.5955 - Peritoneo-venous shunt.  

Code of Federal Regulations, 2014 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5955 Peritoneo-venous shunt. (a) Identification. A...

2014-04-01

135

21 CFR 876.5955 - Peritoneo-venous shunt.  

Code of Federal Regulations, 2013 CFR

...FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5955 Peritoneo-venous shunt. (a) Identification. A...

2013-04-01

136

Zero tolerance to shunt infections: can it be achieved?  

PubMed Central

Objective: To evaluate the rigid application of a technique of shunt placement aimed at the eradication of postoperative shunt infection in neurosurgical practice. Method: All shunt procedures were performed or closely supervised by the senior author (MSC). The essentials were the use of intravenous peri- and postoperative antimicrobials, rigid adherence to classical aseptic technique, liberal use of topical antiseptic (Betadine®), and avoidance of haematomas. Results: Of 176 operations, 93 were primary procedures; 33 patients underwent revisions, some multiple. Only one infection occurred, seven months postoperatively, secondary to appendicitis with peritonitis. The infecting Streptococcus faecalis appeared to ascend from the abdominal cavity. Conclusion: A rigidly applied protocol and strict adherence to sterile technique can reduce shunt infections to a very low level. PMID:14707314

Choksey, M; Malik, I

2004-01-01

137

Vibration damping with shunted piezoceramics: Fundamentals and technical applications  

NASA Astrophysics Data System (ADS)

This paper describes the damping performance of shunted piezoceramics for passive LR-networks, negative capacitance shunts (LRC) and the SSDI-switching technique. The calculations are based on a general description for mechanical structures with piezoelectric elements. Normalized parameters are introduced and the damping performance described by the generalized electromechanical coupling coefficient. For every electrical shunting the optimal network parameters are determined and the resulting maximum damping is compared. Additionally, a squealing disc brake and a bladed disc model are studied as technical applications. Practical realizations for the inclusion of the piezoelements and measurements are presented which validate the calculated damping performance. In particular, it is shown that the shunted piezoceramics are capable to suppress the brake squealing.

Neubauer, Marcus; Wallaschek, Jörg

2013-03-01

138

Portosystemic myelopathy: a rare neurological presentation of portosystemic shunts.  

PubMed

Portosystemic myelopathy is an unusual complication in patients with chronic liver disease with hepatic encephalopathy and portosystemic shunts. Here we present a case of 35-year-old male patient who presented to us with difficulty in walking and progressive stiffness in both lower limbs for two months. He had undergone splenectomy with distal splenorenal shunt 20 years back. On physical examination, he had spasticity in both lower limbs of grade 3, with minimal pyramidal weakness in lower limbs, brisk knee and ankle jerks. The plantar response was extensor. Upper limb examination was normal. On investigations, he had hypoalbuminemia, hyperbilirubinemia, increased plasma ammonia levels. Contrast enhanced CT scan abdomen revealed dilated splenorenal shunt and MRI spine showed no spinal cord compression. Electromyoneurogram was also normal. Spastic paraparesis due to portosystemic shunts was diagnosed. Liver transplantation can reverse the myelopathy only in earlier stages, hence early and accurate diagnosis is important. PMID:25755460

Rao, Prasanna K S; Sheth, Keyur A; Nadig, Raghunandan; Patil, Mallikarjun; Channagiri, Adarsh K

2012-12-01

139

Essentially nonlinear piezoelectric shunt circuits applied to mistuned bladed disks  

NASA Astrophysics Data System (ADS)

An essentially nonlinear piezoelectric shunt circuit is proposed for the practical realization of nonlinear energy sink, and then applied to a mistuned bladed disk for blade vibration reduction. First, the global dynamics of a single degree-of-freedom linear mechanical oscillator, coupled to an essentially nonlinear shunted piezoelectric attachment, is studied. Under certain conditions, the nonlinear targeted energy transfer, i.e. a fast, passive energy transfer from the mechanical oscillator to the nonlinear attachment is observed. A numerical method, referred to as the variable-coefficient harmonic balance method, is developed to calculate quasi-periodic responses arising in the electromechanical system under harmonic forcing. Characterized by the nonexistence of a resonance frequency, the essentially nonlinear shunt circuit is able to work robustly over a broad frequency band with a smaller inductance requirement compared with the linear resonant shunt circuit.

Zhou, B.; Thouverez, F.; Lenoir, D.

2014-04-01

140

Ventriculo-peritoneal shunt infection in a patient on hemodialysis.  

PubMed

Sepsis is an important and serious complication in hemodialysis (HD) patients. Here we report on a case of spina bifida with ventriculo-peritoneal (VP) shunt infection who was on HD and underwent at least 5 months of investigations before a source of the infection was found and eventually treated successfully. We believe this to be the first reported case of VP shunt-associated sepsis in a patient on HD. PMID:18638086

Thet, Yupar; Myint, Win; Myint, Wynne; Hughes, David; Crowe, Alex V; Banerjee, Anindya

2008-07-01

141

Ventriculoperitoneal shunt infection with Mycobacterium fortuitum: a rare offending organism.  

PubMed

Postsurgical infection is one of the greatest potential morbidities of ventriculoperitoneal shunt surgery. The majority of infections can be linked to contamination with skin flora at the time of surgery, a phenomenon that has been well described. However, there is a paucity of literature regarding infection with nontuberculous mycobacteria. The authors report a case of postoperative ventriculoperitoneal shunt infection with Mycobacterium fortuitum and review the available neurosurgical literature and treatment strategies. PMID:25325413

Cadena, Gilbert; Wiedeman, Jean; Boggan, James E

2014-12-01

142

Ventricular septal defect with bidirectional shunting: Mathematical considerations  

Microsoft Academic Search

Previously proposed formulae for the quantitative estimation of bidirectional shunts across ventricular septal defects require\\u000a determination of the oxygen contents of mixed venous, pulmonary artery, pulmonary venous, and aortic blood. Because these\\u000a formulae do not take into account the mixing of oxygenated with unoxygenated blood within the ventricles, their use must result\\u000a in underestimation of shunt flows in each direction.

Howard K. Thompson; Robert H. Peter; Henry D. McIntosh

1966-01-01

143

Embolization of Portosystemic Shunt for Treatment of Recurrent Hepatic Encephalopathy  

PubMed Central

Hepatic encephalopathy in the setting of advanced chronic liver disease, occurs following a precipitating factor and generally responds to correction of the precipitating factor and anticoma measures. We report the case of a lady with Child A cirrhosis who presented with frequent episodes of hepatic encephalopathy without any precipitating factors. She was found to be having a large portosystemic shunt. The shunt was obliterated by coil embolotherapy following which there was no further episodes of encephalopathy. PMID:25755535

Gopalakrishna, Rajesh; Hurkadli, Preetham S.; Puthukudy, Nazar K.; Nair, Harikumar R.

2014-01-01

144

Shunt revision by coagulation with retention of the ventricular catheter.  

PubMed

Intraluminal coagulation of a ventricular catheter followed by its removal and replacement is a technique used for proximal shunt revision. The authors describe experience leaving the original catheter in place when flow of CSF is established by the coagulation. Advantages of this modification include maintenance of ventricular access when the ventricles are small and the possibility of reducing the incidence of subsequent shunt obstruction by mitigating intraventricular hemorrhage caused by catheter removal. PMID:9792956

Hudgins, R J; Boydston, W R

1998-08-01

145

Bleeding oesophageal varices: the management of shunt rejects.  

PubMed Central

It is noted that the majority of patients with bleeding oesophageal varices are not suitable for portal-systemic shunting operations. In addition the high incidence of post-shunt encephalopathy has encouraged the use of a direct attack on the varices. The results of injection sclerotherapy in 170 patients and oesophageal transection in 60 patients demonstrate acceptable control of bleeding without precipitation of encephalopathy. Images Fig. 1 Fig. 2 PMID:6972723

Johnston, G. W.

1981-01-01

146

Aberrant Gene Expression in Dogs with Portosystemic Shunts  

PubMed Central

Congenital portosystemic shunts are developmental anomalies of the splanchnic vascular system that cause portal blood to bypass the liver. Large-breed dogs are predisposed for intrahepatic portosystemic shunts (IHPSS) and small-breed dogs for extrahepatic portosystemic shunts (EHPSS). While the phenotype resulting from portal bypass of the liver of the two types of shunt is identical, the genotype and molecular pathways involved are probably different. The aim of this study was to gain insight into the pathways involved in the different types of portosystemic shunting. Microarray analysis of mRNA expression in liver tissue from dogs with EHPSS and IHPSS revealed that the expression of 26 genes was altered in either IHPSS or EHPSS samples compared with that in liver samples from control dogs. Quantitative real-time PCR of these genes in 14 IHPSS, 17 EHPSS, and 8 control liver samples revealed a significant differential expression of ACBP, CCBL1, GPC3, HAMP, PALLD, VCAM1, and WEE1. Immunohistochemistry and Western blotting confirmed an increased expression of VCAM1 in IHPSS but its absence in EHPSS, an increased WEE1 expression in IHPSS but not in EHPSS, and a decreased expression of CCBL1 in both shunt types. Regarding their physiologic functions, these findings may indicate a causative role for VCAM1 in IHPSS and WEE1 for IHPSS. CCBL1 could be an interesting candidate to study not yet elucidated aspects in the pathophysiology of hepatic encephalopathy. PMID:23451256

Grinwis, Guy C. M.; Kummeling, Anne; van Gils, Ingrid H. M.; Koerkamp, Marian J. A. Groot.; van Leenen, Dik; Holstege, Frank C. P.; Penning, Louis C.; Rothuizen, Jan; Leegwater, Peter A. J.; Spee, Bart

2013-01-01

147

Vibration control of an HDD disk-spindle system utilizing piezoelectric bimorph shunt damping: I. Dynamic analysis and modeling of the shunted drive  

Microsoft Academic Search

This work proposes a new piezoelectric shunt damping methodology to control the vibration of a computer hard disk drive (HDD) disk-spindle system. The first part of this work (part I) deals with dynamic modeling of the piezoelectric shunted drive, while the second part of this work (part II) covers experimental implementation of the proposed shunt circuits. In the modeling, a

S. C. Lim; S. B. Choi

2007-01-01

148

78 FR 64933 - Texas Eastern Transmission, LP; Notice of Application  

Federal Register 2010, 2011, 2012, 2013, 2014

...public convenience and necessity to construct its Emerald Longwall Mine Panel D1 Project. Texas Eastern...due to anticipated longwall mining activities of Emerald Coal Resources, LP (Emerald) in Greene County, Pennsylvania in Panel...

2013-10-30

149

Further developments in LP-based optimal power flow  

SciTech Connect

Over the past twenty five years, the optimal power flow (OPF) approach that has received the most widespread practical application is the one based on linear programming (LP). Special customized LP methods have been utilized primarily for fast reliable security-constrained dispatch using decoupled separable OPF problem formulations. They have been used in power system planning, operations and control. Nevertheless, while the LP approach has a number of important attributes, its range of application in the OPF field has remained somewhat restricted. This paper describes further developments that have transformed the LP approach into a truly general-purpose OPF solver, with computational and other advantages over even recent nonlinear programming (NLP) methods. The nonseparable loss-minimization problem can now be solved, giving the same results as NLP on power systems of any size and type.

Alsac, O.; Bright, J.; Prais, M.; Stott, B.P (Power Computer Applications Corp., Mesa, AZ (US))

1990-08-01

150

Marketing LP-gas motor fuel in Europe  

Microsoft Academic Search

The acceptance of LP-gas (autogas) as a motor fuel in Europe depends primarily on price since the European driver is concerned with the financial savings it offers rather than the ecological benefits. Because LP-gas production in Europe is oil-based, the supply depends on the supply of crude oil from the Middle East. Thus the growth of the autogas market is

Mol

1975-01-01

151

Comparisons of QP and LP Based Learning from Empirical Data  

Microsoft Academic Search

The quadratic programming (QP) and the linear programming (LP) based method are recently the most popular learning methods from empirical data. Support vector machines (SVMs) are the newest models based on QP al- gorithm in solving the nonlinear regression and classification problems. The LP based\\u000a learning also controls both the number of basis functions in a neural net- work (i.e.,

Vojislav Kecman; Tiru S. Arthanari

2001-01-01

152

Temporary arterial shunts to maintain limb perfusion after arterial injury: an animal study  

NASA Technical Reports Server (NTRS)

BACKGROUND: Temporary shunt placement can quickly restore perfusion after extremity arterial injury. This study examined the adequacy of limb blood flow with shunt use, non-heparin-bonded shunt patency over prolonged periods, and the safety of this technique. METHODS: Common iliac arteries were divided and 4.0-mm Silastic Sundt shunts placed in 16 anesthetized pigs. Eight (group I) had shunts placed immediately; eight others (group II) were shunted after an hour of limb ischemia and hemorrhagic shock. Physiologic parameters and femoral artery blood flow in both hindlimbs were continuously monitored. Limb lactic acid generation, oxygen utilization, and hematologic and metabolic effects were serially evaluated for 24 hours. RESULTS: Shunts remained patent in 13 of 16 pigs. Shunts thrombosed in two group I animals because of technical errors, but functioned well after thrombectomy and repositioning. Patency could not be maintained in one animal that died from shock. Flow in group I shunted limbs was 57 (+/-11 SD) % of control. For group II animals in shock, shunted limb flow initially averaged 46 +/- 15% of control, but 4 hours after shunt placement, the mean limb blood flow was the same as in group I. Increased oxygen extraction compensated for the lower flow. Lactic acid production was not increased in comparison to control limbs. CONCLUSION: Shunts provided adequate flow in this model of extremity trauma. Correctly placed shunts stayed patent for 24 hours, without anticoagulation, if shunt placement followed resuscitation.

Dawson, D. L.; Putnam, A. T.; Light, J. T.; Ihnat, D. M.; Kissinger, D. P.; Rasmussen, T. E.; Bradley, D. V. Jr

1999-01-01

153

[A case of repeated shunt malfunctions with eosinophilic meningitis caused by silicone allergy].  

PubMed

The ventricular-peritoneal shunt for hydrocephalus is a well-known and established method but is sometimes complicated by shunt malfunction due to several causes. Eosinophilic meningitis is a rare disease, but has occasionally been reported as a cause of shunt malfunction. Here, we report the case of a 74-year-old woman with repeated shunt malfunction and eosinophilic meningitis due to a silicone allergy. Originally, the patient received a ventricular-peritoneal shunt for normal pressure hydrocephalus secondary to subarachnoid hemorrhage. However, shunt malfunction was identified 6 weeks later, and the first shunt revision was performed using a new shunt system from a different company. Further evaluation to identify the cause of the shunt malfunction revealed no abnormal findings, except for eosinophilia in the serum and cerebrospinal fluid. A second shunt malfunction was identified 16 weeks after the first shunt revision. We therefore concluded that eosinophilic meningitis caused by a silicone allergy might be the real culprit and a second shunt revision was performed using a silicone "extracted" tube. Since then, the patient's course has been free from shunt malfunction. In this case, the serum and cerebrospinal fluid eosinophilia were useful markers for identifying the cause of repeated shunt malfunctions. The silicone "extracted" tube may be helpful for diagnosis and therapy. PMID:25433060

Kambara, Mizuki; Miyazaki, Takeshi; Yoshikane, Tsutomu; Sugimoto, Keiji; Akiyama, Yasuhiko

2014-12-01

154

Vestibular neurectomy with simultaneous endolymphatic subarachnoid shunt.  

PubMed

The purpose of this study was to assess the advantages of combined vestibular neurectomy (VN) and endolymphatic subarachnoid shunt (ELSS) surgeries in classic Menière's disease. We performed a retrospective analysis of the results of 116 patients with classic Menière's disease who were operated on via a posterior fossa approach. All patients underwent selective VN. In 86 of the patients, ELSS surgery was performed in conjunction with VN via the posterior fossa, which is called two-in-one surgery. Among the 86 patients who underwent two-in-one surgery, hearing preservation was achieved in 71 (82.5%), and the vertigo control rate was 96.5%. In patients who underwent VN without ELSS, hearing stabilization was achieved in 24 (80%), and the vertigo control rate was 96.7%. The hearing results and vertigo control rates were similar in the groups. Aural fullness subsided in 62 (72.1%) of the patients who underwent VN plus ELSS and in 14 (46.7%) who underwent VN alone. The recovery of fullness was significantly better with the combined VN and ELSS procedure ( P<0.05). In conclusion, although the two-in-one operation is a new procedure, its results for vertigo control and hearing stabilization are not different from that of VN alone. The only significant advantage of this technique was the achievement of a substantial improvement in the reduction of aural fullness. PMID:12107526

Göksu, Nebil; Bayazit, Yildirim A; Abdulhalik, Abdullah; Kemalo?lu, Yusuf K

2002-05-01

155

Attenuation of Congenital Portosystemic Shunt Reduces Inflammation in Dogs  

PubMed Central

Liver disease is a major cause of morbidity and mortality. One of the most significant complications in patients with liver disease is the development of neurological disturbances, termed hepatic encephalopathy. The pathogenesis of hepatic encephalopathy is incompletely understood, which has resulted in the development of a wide range of experimental models. Congenital portosystemic shunt is one of the most common congenital disorders diagnosed in client owned dogs. Our recent studies have demonstrated that the pathophysiology of canine hepatic encephalopathy is very similar to human hepatic encephalopathy, which provides strong support for the use of dogs with a congenital portosystemic shunt as a naturally occurring model of human hepatic encephalopathy. Specifically, we have demonstrated an important role for ammonia and inflammation in the development of hepatic encephalopathy in dogs with a congenital portosystemic shunt. Despite the apparent importance of inflammation in driving hepatic encephalopathy in dogs, it is unclear whether inflammation resolves following the successful treatment of liver disease. We hypothesized that haematological and biochemical evidence of inflammation, as gauged by neutrophil, lymphocyte and monocyte concentrations together with C-reactive protein concentrations, would decrease following successful treatment of congenital portosystemic shunts in dogs. One hundred and forty dogs with a congenital portosystemic shunt were enrolled into the study. We found that the proportion of dogs with a monocyte concentration above the reference range was significantly greater in dogs with hepatic encephalopathy at time of initial diagnosis. Importantly, neutrophil and monocyte concentrations significantly decreased following surgical congenital portosystemic shunt attenuation. We also found a significant decrease in C-reactive protein concentrations following surgical attenuation of congenital portosystemic shunts. Our study demonstrates that haematological and biochemical indices of inflammation reduce following successful treatment of the underlying liver disorder. PMID:25658922

Tivers, Michael S.; Handel, Ian; Gow, Adam G.; Lipscomb, Victoria J.; Jalan, Rajiv; Mellanby, Richard J.

2015-01-01

156

Cost of preventing variceal rebleeding with transjugular intrahepatic portal systemic shunt and distal splenorenal shunt  

PubMed Central

Background and aims We examined the cost and cost effectiveness of distal splenorenal shunt (DSRS) and transjugular intrahepatic portosystemic shunt (TIPS) in the prevention of variceal rebleeding. Subjects Participants in randomized controlled trial comparing DSRS to TIPS. Methods Quality of life (QOL) measured using SF-36 preceding randomization and yearly thereafter. Cost utility analysis was performed using Data Treeage ®. Costs for both in- and out-patient events and interventions were obtained for each patient. Costs using coated stents were estimated using different rates of stenosis. Incremental cost effectiveness ratios (ICERs) were determined at 1, 3 and 5 years. Results The average yearly costs of managing patients after TIPS and DSRS over 5 years were similar, $16,363 and $13,492 respectively. Cost of TIPS for surviving patients exceeded the cost of DSRS at years 3 and 5 but not significantly. ICERs per life saved favored TIPS at year 5 ($61,000). If coated rather than bare stents were used the cost-effectiveness of TIPS increased slightly. Conclusions TIPS is as effective as DSRS in preventing variceal rebleeding and may be more cost effective. TIPS, in all aspects, is equal to DSRS in the prevention of variceal rebleeding in patients who are medical failures. PMID:18045724

Boyer, Thomas D; Henderson, J Michael; Heerey, Adrienne M; Arrigain, Susana; Konig, Vicky; Jason, Connor; Abu-Elmagd, Kareem; Galloway, John; Rikkers, Layton F; Jeffers, Lennox

2009-01-01

157

LP DAAC and MEaSUREs - Optimizing Collection Inception  

NASA Astrophysics Data System (ADS)

The Land Processes Distributed Active Archive Center (LP DAAC) is a selected NASA Earth Observing System (EOS) Data and Information System (EOSDIS) DAAC supporting the Making Earth System Data Records for Use in Research Environments (MEaSUREs) Program to contribute in providing long-term, consistent, and mature data products. The LP DAAC has identified three essential components for the MEaSUREs collection inception. The first component includes a framework of LP DAAC's data lifecycle including overall inception of products, curation of products, and long-term archiving of products. The second component fuses data producer and data provider operations, interleaving key personnel into key processes throughout the project. The third component integrates and evolves stakeholder elements into a standard methodology, alongside affording an overall homogeneous data delivery system for MEaSUREs collections. As an active participant on the Metadata Evolution for NASA Data Systems (MENDS) Tiger Team, the LP DAAC is working to categorize all data model elements into the ISO 19115 international metadata standard. This poster depicts how each of these three components optimizes the LP DAAC MEaSUREs collection inception process.

Bennett, S.

2013-12-01

158

Ramp acceleration and hydraulic conductivity (Lp) of living capillaries  

PubMed Central

Living mesenteric capillaries with either an intact or disrupted glycocalyx were challenged with ramp change in shear stress (??). Animals (Rana pipiens) were divided randomly into two experimental groups and two true capillaries (TC) per animal were investigated. The modified Landis technique was combined with intravital microscopy to view individual TC and assess hydraulic conductivity (Lp), an index of capillary function. Median Lp was 3.2 × 10?7 for control and 11.8 × 10?7 cm·s?1·cm H2O?1 after mild, brief (1 min) pronase treatment (P<0.0001). Analysis by stimulus component showed that Lp for untreated capillaries was related negatively to ramp acceleration (R2=0.46, P<0.0001, n=38) and positively to ?? magnitude (R2=0.28, P=0.0006, n=38). Disrupting the capillary glycocalyx revealed a positive and previously unknown relationship between ramp acceleration and Lp (R2=0.44, P=0.002, n=19) plus an upward shift (increased intercept) of the magnitude ??-Lp relationship compared to abrupt stimulation. These data suggest that bloodstream hemodynamics may impact capillary function. Further, an intact glycocalyx may protect capillaries when blood flow changes. PMID:20025890

Williams, Donna A.

2009-01-01

159

Fractured inlet connecting tube of the flat bottom flushing device of a posterior fossa cystoperitoneal shunt  

PubMed Central

Background: There are well-known complications for shunt procedures. Shunt fracture or disconnection is the second most frequent cause of shunt malfunction in children. Shunt disconnection is not a common cause of shunt malfunction in the early period after installation, especially in the adulthood. Case Description: Fracture of the proximal (inlet) connector of a flat-based shunt installed for decompression of a large posterior fossa arachnoid cyst in a 31-year-old female with signs of increased intracranial pressure led to recurrence of her symptoms 6 months after surgery. Conclusion: Awareness of the possibility of fracture site in the junction of the inlet connector of flat bottom shunt systems is warranted and can be diagnosed by three-dimensional computed tomography (3D CT) imaging without performing shunt series study. PMID:25789198

Amirjamshidi, Abbas; Abbasioun, Kazem; Ghassemi, Babak

2015-01-01

160

Dual-shunt branch circuit and harmonic suppressed device application  

NASA Astrophysics Data System (ADS)

A new type of planar left handed transmission line (LH TL) circuit was investigated theoretically and experimentally. It consists of a capacitive gap and Koch-shaped extended complementary single split ring resonator pair (K-ECSSRRP) etched on the host conductor line and ground plane, respectively. Distinguished from any previous counterparts possessing only one shunt branch, the current K-ECSSRRP features dual-shunt branches in the capacitive-inductive equivalent circuit. As a consequence, an additional attenuation pole is introduced above the upper edge passband of the LH TL, which is a very desirable characteristic. For verification and illustration of potential applications, a compact diplexer is designed and fabricated with an enhanced harmonic suppression. The dual-shunt branch circuit is of reference value and suggests a variety of device implementations where miniaturization and harmonic suppression are major concerns.

Xu, He-Xiu; Wang, Guang-Ming; Xu, Zhi-Ming; Chen, Xin; Yu, Zhongwu; Geng, Lin

2012-08-01

161

Tunable-delay shunts for paper microfluidic devices.  

PubMed

We demonstrate a novel method for controlling fluid flow in paper-based devices. The method delays fluid progress through a porous channel by diverting fluid into an absorbent pad-based shunt placed into contact with the channel. Parameters to control the delay include the length and the thickness of the shunt. Using this method, reproducible delays ranging from 3 to 20 min were achieved. A simple electrical circuit model was presented and used to predict the delays in a system. Results from the model showed good agreement with experimental observations. Finally, the shunts were used for the sequential delivery of fluids to a detection zone in a point-of-care compatible folding card device using biochemical reagents for the amplified detection of the malaria protein PfHRP2. PMID:24245747

Toley, Bhushan J; McKenzie, Brittney; Liang, Tinny; Buser, Joshua R; Yager, Paul; Fu, Elain

2013-12-01

162

Tunable-Delay Shunts for Paper Microfluidic Devices  

PubMed Central

We demonstrate a novel method for controlling fluid flow in paper-based devices. The method delays fluid progress through a porous channel by diverting fluid into an absorbent pad-based shunt placed into contact with the channel. Parameters to control the delay include the length and the thickness of the shunt. Using this method, reproducible delays ranging from 3 to 20 minutes were achieved. A simple electrical circuit model was presented and used to predict the delays in a system. Results from the model showed good agreement with experimental observations. Finally, the shunts were used for the sequential delivery of fluids to a detection zone in a point-of-care compatible folding card device using biochemical reagents for the amplified detection of the malaria protein PfHRP2. PMID:24245747

Toley, Bhushan J.; McKenzie, Brittney; Liang, Tinny; Buser, Joshua R.; Yager, Paul; Fu, Elain

2014-01-01

163

Temporal and spatial distributions of carbon shunting arc plasma  

NASA Astrophysics Data System (ADS)

The temporal and spatial distributions of a magnetically driven shunting arc plasma were obtained using time-resolved probe measurement. A shunting arc was produced using a carbon rod and accelerated along a pair of rail electrodes by a Lorenz force. The pulse current for driving and maintaining the plasma was supplied from a 20 µF capacitor charged by a dc power supply. Double and single probes were employed to obtain the ion density of the shunting arc plasma. An ion density of 1 × 1019 m?3 was obtained at a distance of 50 mm from the carbon rod 15 µs after applying voltage. The ion density decreased to 2.0 × 1018 m?3 with increasing distance from 50 to 150 mm. The ion density changed with the energy inputted into the plasma.

Takaki, Koichi; Konishi, Takumi; Mikawa, Ryota; Takahashi, Kazunori; Yukimura, Ken

2015-01-01

164

In Vitro and In Vivo Comparison of Two Suprachoroidal Shunts  

PubMed Central

Purpose. To compare fibrosis, aqueous humor dynamics, and intraocular pressure (IOP) of two suprachoroidal shunts as part of a new class of glaucoma drainage devices. Methods. Following proliferation analysis in vitro, 20 rabbits were implanted with either a gold shunt (GS, GMSplus+, SOLX) or a polypropylene shunt (PS, Aquashunt, OPKO). Ten eyes received mitomycin C (MMC) and triamcinolone. Peak and trough IOP were monitored with a pneumatonometer and tono-pen for 15 weeks. Aqueous humor dynamics were evaluated fluorophotometrically and tonographically. Fibrosis was quantified. Results. In vitro proliferation was similar. In vivo, both shunts were devoid of foreign body reaction but exhibited fibrosis, and GS showed vascularization. There was no significant difference in aqueous or uveoscleral flow. Preoperative morning IOP was 23.7 ± 2 mm Hg, and evening IOP was 26.5 ± 2 mm Hg (P = 0.000). Morning IOP was decreased through 15 weeks and evening IOP through 8 weeks in all groups. The morning IOP decrease was most profound at 15 weeks in PS (41%) compared to GS (18%). Antifibrotics initially enhanced but eventually diminished shunt performance. At 15 weeks, thickness of scleral fibrosis was greater in GS (246 ± 47 ?m) and PS (188 ± 47 ?m, P = 0.285) compared with GS+MMC (109 ± 26 ?m, P = 0.023 to GS) and PS+MMC (48 ± 30 ?m, P = 0.028 to PS). Conclusions. In a rabbit model, suprachoroidal polypropylene and gold shunts allow access to a new drainage pathway with different IOP profiles that can be modified with antifibrotics. PMID:23847318

Oatts, Julius T.; Zhang, Ze; Tseng, Harry; Shields, M. Bruce; Sinard, John H.; Loewen, Nils A.

2013-01-01

165

Shunted Piezoelectric Vibration Damping Analysis Including Centrifugal Loading Effects  

NASA Technical Reports Server (NTRS)

Excessive vibration of turbomachinery blades causes high cycle fatigue problems which require damping treatments to mitigate vibration levels. One method is the use of piezoelectric materials as passive or active dampers. Based on the technical challenges and requirements learned from previous turbomachinery rotor blades research, an effort has been made to investigate the effectiveness of a shunted piezoelectric for the turbomachinery rotor blades vibration control, specifically for a condition with centrifugal rotation. While ample research has been performed on the use of a piezoelectric material with electric circuits to attempt to control the structural vibration damping, very little study has been done regarding rotational effects. The present study attempts to fill this void. Specifically, the objectives of this study are: (a) to create and analyze finite element models for harmonic forced response vibration analysis coupled with shunted piezoelectric circuits for engine blade operational conditions, (b) to validate the experimental test approaches with numerical results and vice versa, and (c) to establish a numerical modeling capability for vibration control using shunted piezoelectric circuits under rotation. Study has focused on a resonant damping control using shunted piezoelectric patches on plate specimens. Tests and analyses were performed for both non-spinning and spinning conditions. The finite element (FE) shunted piezoelectric circuit damping simulations were performed using the ANSYS Multiphysics code for the resistive and inductive circuit piezoelectric simulations of both conditions. The FE results showed a good correlation with experimental test results. Tests and analyses of shunted piezoelectric damping control, demonstrating with plate specimens, show a great potential to reduce blade vibrations under centrifugal loading.

Min, James B.; Duffy, Kirsten P.; Provenza, Andrew J.

2011-01-01

166

Fetal ovarian cyst mimicking a CSF pseudocyst in the setting of shunt failure.  

PubMed

Fetal ovarian cysts are common congenital lesions encountered in the neonatal population. These cysts are typically benign and rarely require any invasive intervention. Abdominal pseudocyst formation as a result of a ventriculoperitoneal shunt is a relatively infrequent occurrence and is similarly an uncommon cause of shunt failure. The authors present the case of a 4-month-old girl with shunted hydrocephalus who presented with shunt failure from a suspected abdominal pseudocyst that was found to be a fetal ovarian cyst. PMID:25343733

Calayag, Mark; Malone, Christian Cantillano; Drake, Brian; Chavhan, Govind; Rutka, James T

2015-01-01

167

Transjugular intrahepatic portosystemic stent-shunt (TIPSS) occlusion and the role of biliary venous fistulae  

Microsoft Academic Search

Background\\/Aim: The aim of this study was to assess the pathology and pathogenic mechanisms involved in the occlusion of transjugular intrahepatic portosystemic stent-shunts.Methods: Thirty-four patients with transjugular intrahepatic portosystemic stent-shunt who had at least two portographic assessments of shunt function were the subjects of this study. The contents of any shunt demonstrating >70% stenosis were biopsied before balloon dilatation. Further

Rajiv Jalan; David J. Harrison; Doris N. Redhead; Peter C. Hayes

1996-01-01

168

Laparoscopic Hysteropexy in a Patient with Spina Bifida and Ventriculoperitoneal Shunt  

PubMed Central

Laparoscopic repair of pelvic organ prolapse in patients with ventriculoperitoneal shunts has not been previously described. The optimum management of patients with ventriculoperitoneal shunts undergoing laparoscopy is uncertain. We describe the case of a 21-year-old female patient with spina bifida and ventriculoperitoneal shunt who underwent laparoscopic hysteropexy for severe pelvic organ prolapse. The implications of performing laparoscopy on patients with ventriculoperitoneal shunts are reviewed along with strategies to reduce potential intraoperative complications. PMID:21902988

Askari, Reza; Kasturi, Seshadri; Ravangard, Samadh F.

2011-01-01

169

Treatment of Portosystemic Shunt Myelopathy with a Stent Graft Deployed through a Transjugular Intrahepatic Route  

SciTech Connect

A case of surgically created splenorenal shunt complicated with shunt myelopathy was successfully managed by placement of a stent graft within the splenic vein to close the portosystemic shunt and alleviate myelopathy. To our knowledge, this is the first report of a case of shunt myelopathy in a patient with noncirrhotic portal fibrosis without cirrhosis treated by a novel technique wherein a transjugular intrahepatic route was adopted to deploy the stent graft.

Jain, Deepak, E-mail: deepakjain02@yahoo.com; Arora, Ankur, E-mail: aroradrankur@yahoo.com [Institute of Liver and Biliary Sciences, Department of Radiology (India); Deka, Pranjal, E-mail: drpranjaldeka@gmail.com [Institute of Liver and Biliary Sciences, Department of Hepatopancreatobiliary Surgery (India); Mukund, Amar, E-mail: dramarmukund@gmail.com; Bhatnagar, Shorav, E-mail: drshorav@yahoo.com [Institute of Liver and Biliary Sciences, Department of Radiology (India); Jindal, Deepti, E-mail: deepijindal@rediffmail.com; Kumar, Niteen, E-mail: drniteenkumar@gmail.com; Pamecha, Viniyendra, E-mail: viniyendra@yahoo.co.uk [Institute of Liver and Biliary Sciences, Department of Hepatopancreatobiliary Surgery (India)

2013-08-01

170

Ventriculoperitoneal shunt infections in children. A 6-year study.  

PubMed

In a study of ventriculoperitoneal shunt infections conducted retrospectively between 1983 and 1987 and prospectively in 1988 39 infections from 372 shunt procedures (incidence 10.5%) were identified. The most common organism isolated was Staphylococcus aureus (18; 47%) followed by S. epidermidis (10; 26%). Forty-two per cent of staphylococci were methicillin-resistant. Gram-negative infections were associated with myelomeningoceles and Gram-positive infections with other forms of hydrocephalus (P = 0.048). Lymphocyte predominance was found more frequently than polymorphonuclear predominance in cerebrospinal fluid. PMID:1994483

Cotton, M F; Hartzenberg, B; Donald, P R; Burger, P J

1991-02-01

171

Potts Shunt in Patients with Primary Pulmonary Hypertension  

PubMed Central

Idiopathic pulmonary arterial hypertension eventually leads to right-sided heart failure and sudden death. Its mortality rate in children is still high, despite improvements in pharmacological therapy, and therefore novel treatments are necessary. The Potts shunt, which creates an anastomosis between the left pulmonary artery and the descending aorta, has been proposed as a theoretically promising palliative surgical technique to decompress the right ventricle. We report the case of a 12-year-old girl with suprasystemic idiopathic pulmonary hypertension and right ventricular failure who underwent a Potts shunt for palliation with good short-term results. PMID:25705598

Kim, Sue Hyun; Jang, Woo-Sung; Lim, Hong-Gook; Kim, Yong-Jin

2015-01-01

172

Protein adsorption to hydrocephalus shunt catheters: CSF protein adsorption  

PubMed Central

OBJECTIVE—To assess the quantity and nature of the proteins that adsorb to hydrocephalus shunt catheters after implantation, and to determine whether sufficient could accumulate to obstruct the catheter.?DESIGN—Elution of proteins from 102 explanted shunt catheters, with protein assay and electrophoresis of the eluate, and scanning electron microscopy (SEM) of the catheters.?RESULTS—The amount of protein elutable was extremely low, and significant protein, apart from a thin film, was not found on SEM. Qualitative analysis disclosed that most of the adsorbed protein was albumin.?CONCLUSIONS—Protein deposition on hydrocephalus catheters does not occur in sufficient quantities to cause catheter obstruction.?? PMID:9598681

Brydon, H.; Keir, G.; Thompson, E.; Bayston, R.; Hayward, R.; Harkness, W.

1998-01-01

173

Sparse logistic regression with Lp penalty for biomarker identification.  

PubMed

In this paper, we propose a novel method for sparse logistic regression with non-convex regularization Lp (p <1). Based on smooth approximation, we develop several fast algorithms for learning the classifier that is applicable to high dimensional dataset such as gene expression. To the best of our knowledge, these are the first algorithms to perform sparse logistic regression with an Lp and elastic net (Le) penalty. The regularization parameters are decided through maximizing the area under the ROC curve (AUC) of the test data. Experimental results on methylation and microarray data attest the accuracy, sparsity, and efficiency of the proposed algorithms. Biomarkers identified with our methods are compared with that in the literature. Our computational results show that Lp Logistic regression (p <1) outperforms the L1 logistic regression and SCAD SVM. Software is available upon request from the first author. PMID:17402921

Liu, Zhenqiu; Jiang, Feng; Tian, Guoliang; Wang, Suna; Sato, Fumiaki; Meltzer, Stephen J; Tan, Ming

2007-01-01

174

Compensation characteristics of the combined system of shunt passive and series active filters  

Microsoft Academic Search

A combined system of shunt passive and small rated series active filters, as well as its operating principle and steady compensation characteristics, was previously presented by the authors (1988). The combined system can greatly reduce problems of using only the shunt passive or shunt active filters and is suitable for harmonic compensation for large VA-rated loads in power systems. Transient

Fang Zheng Peng; Hirofumi Akagi; Akira Nabae

1993-01-01

175

Treatment of Staphylococcus epidermidis Ventriculo–Peritoneal Shunt Infection with Linezolid  

Microsoft Academic Search

Gram-positive bacterial meningitis frequently complicates ventriculo-peritoneal (VP) shunts used for hydrocephalus. Linezolid, an oxazolidinone, is active against Gram-positive cocci, and has excellent CSF penetration. We present a 22-year-old woman who was cured of a Staphylococcus epidermidis VP shunt infection via shunt removal and intravenous linezolid.

C. J. Gill; M. A. Murphy; D. H. Hamer

2002-01-01

176

Dominant resonant mode damping of a piezoelectric tube nanopositioner using optimal sensorless shunts  

E-print Network

shunts, optimized using H2 and H techniques. These shunts damp the modal amplitude of the first resonantDominant resonant mode damping of a piezoelectric tube nanopositioner using optimal sensorless the first mechanical resonance frequency. Feedback control techniques and shunt damping methods have shown

Fleming, Andrew J.

177

New and improved ways to treat hydrocephalus: Pursuit of a smart shunt  

PubMed Central

The most common treatment for hydrocephalus is placement of a cerebrospinal fluid shunt to supplement or replace lost drainage capacity. Shunts are life-saving devices but are notorious for high failure rates, difficulty of diagnosing failure, and limited control options. Shunt designs have changed little since their introduction in 1950s, and the few changes introduced have had little to no impact on these long-standing problems. For decades, the community has envisioned a “smart shunt” that could provide advanced control, diagnostics, and communication based on implanted sensors, feedback control, and telemetry. The most emphasized contribution of smart shunts is the potential for advanced control algorithms, such as weaning from shunt dependency and personalized control. With sensor-based control comes the opportunity to provide data to the physician on patient condition and shunt function, perhaps even by a smart phone. An often ignored but highly valuable contribution would be designs that correct the high failure rates of existing shunts. Despite the long history and increasing development activity in the past decade, patients are yet to see a commercialized smart shunt. Most smart shunt development focuses on concepts or on isolated technical features, but successful smart shunt designs will be a balance between technical feasibility, economic viability, and acceptable regulatory risk. Here, we present the status of this effort and a framework for understanding the challenges and opportunities that will guide introduction of smart shunts into patient care. PMID:23653889

Lutz, Barry R.; Venkataraman, Pranav; Browd, Samuel R.

2013-01-01

178

Successful Embolization of a Spontaneous Mesocaval Shunt Using the Amplatzer Vascular Plug II  

SciTech Connect

A 48-year-old man with alcoholic liver cirrhosis and hepatic encephalopathy was found to have a large, spontaneous mesocaval shunt. The shunt was successfully occluded with the use of an Amplatzer Vascular Plug. To our knowledge, this is the first report of the use of this device to embolize a mesocaval shunt involving the superior mesenteric vein.

Boixadera, Helena, E-mail: hboixadera@hotmail.co [Hospital Vall d' Hebron, Department of Radiology (Spain); Tomasello, Alejandro [Hospital Vall d' Hebron, Department of Interventional Radiology (Spain); Quiroga, Sergi [Hospital Vall d' Hebron, Department of Radiology (Spain); Cordoba, Joan [Hospital Vall d' Hebron, Department of Internal Medicine-Hepatology (Spain); Perez, Mercedes; Segarra, Antoni [Hospital Vall d' Hebron, Department of Interventional Radiology (Spain)

2010-10-15

179

Piezoelectric shunts with a parallel RL circuit for structural damping and vibration control  

Microsoft Academic Search

A study has been made of piezoelectric shunts using a piezoelectric element shunted with a parallel resistor and inductor circuit for passive structural damping and vibration control. It is found that under the optimum tuning condition, the peak amplitude of the displacement versus frequency curve of a structural mode decreases with the increase of the shunt resistance. It becomes a

Shu-Yau Wu

1996-01-01

180

The Intermediate Age Brown Dwarf LP 944-20  

E-print Network

Observations are presented which show that LiI 6708A is detected with equivalent width of 0.53+-0.05A in the proper-motion object LP 944-20 (which is also known as BRI 0337-3535). This Li detection implies that LP 944-20 is a brown dwarf with mass between 0.057 and 0.063Mo and age between 475 and 650Myr, making it the first brown dwarf to have its mass and age precisely determined.

C. G. Tinney

1998-01-17

181

The Intermediate Age Brown Dwarf LP 944-20  

Microsoft Academic Search

Observations are presented which show that LiI 6708A is detected with\\u000aequivalent width of 0.53+-0.05A in the proper-motion object LP 944-20 (which is\\u000aalso known as BRI 0337-3535). This Li detection implies that LP 944-20 is a\\u000abrown dwarf with mass between 0.057 and 0.063Mo and age between 475 and 650Myr,\\u000amaking it the first brown dwarf to have its

C. G. Tinney

1998-01-01

182

77 FR 30589 - SteelRiver Infrastructure Partners LP, SteelRiver Infrastructure Associates LLC, SteelRiver...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Infrastructure Fund North America LP, and Patriot Funding...SteelRiver Infrastructure Fund North America LP (SRIFNA LP), and...5) The Louisiana and North West Railroad Company LLC...O'Connor; 1627 I Street NW., Suite 1100,...

2012-05-23

183

Complications and subsequent removal of retained shunt hardware after endoscopic third ventriculostomy: case series.  

PubMed

This case series highlights multiple complications and subsequent removal of retained shunt hardware in pediatric patients after successful endoscopic third ventriculostomy (ETV). Removal or retention of existing shunt hardware following ETV represents an important dilemma. Prior studies have reported infections and organ perforation related to nonfunctioning shunts but none in the context of successful ETV. Data obtained in 3 children with hydrocephalus treated at the authors' institution were retrospectively reviewed after the patients experienced complications due to retained shunt hardware following ETV. Etiologies of hydrocephalus included tectal glioma and intraventricular hemorrhage. All 3 patients had a history of multiple shunt revisions and underwent urgent ETV in the setting of a shunt malfunction. In each case, the entire shunt system was left in situ, but it became the source of subsequent complications. Two of the 3 patients presented with the shunt infected by gram-negative bacilli 10 days and 4.5 months postoperatively, respectively. The remaining patient experienced wound dehiscence over the shunt valve 4.5 months after ETV. In all patients, the complications were managed successfully by removing the shunt hardware. None of the patients required repeat shunt insertion from the time of removal throughout the follow-up period (mean 24 months, range 9-36 months). During the study period, a total of 6 patients with indwelling shunt hardware underwent ETV with the expectation of being shunt independent. Among these 6 patients, 3 experienced no complications from the retained hardware whereas 3 patients (50%) ultimately experienced adverse consequences related to retained hardware. This case series illustrates complications involving retained shunt hardware after successful ETV. These examples support consideration of shunt removal at the time of ETV in the appropriate context. PMID:23560795

Pindrik, Jonathan; Jallo, George I; Ahn, Edward S

2013-06-01

184

TIPS Versus Peritoneovenous Shunt in the Treatment of Medically Intractable Ascites  

PubMed Central

Objective: We undertook a prospective randomized clinical trial comparing TIPS to peritoneovenous (PV) shunts in the treatment of medically intractable ascites to establish relative efficacy and morbidity, and thereby superiority, between these shunts. Methods: Thirty-two patients were prospectively randomized to undergo TIPS or peritoneovenous (Denver) shunts. All patients had failed medical therapy. Results: After TIPS versus peritoneovenous shunts, median (mean ± SD) duration of shunt patency was similar: 4.4 months (6 ± 6.6 months) versus 4.0 months (5 ± 4.6 months). Assisted shunt patency was longer after TIPS: 31.1 months (41 ± 25.9 months) versus 13.1 months (19 ± 17.3 months) (P < 0.01, Wilcoxon test). Ultimately, after TIPS 19% of patients had irreversible shunt occlusion versus 38% of patients after peritoneovenous shunts. Survival after TIPS was 28.7 months (41 ± 28.7 months) versus 16.1 months (28 ± 29.7 months) after peritoneovenous shunts. Control of ascites was achieved sooner after peritoneovenous shunts than after TIPS (73% vs. 46% after 1 month), but longer-term efficacy favored TIPS (eg, 85% vs. 40% at 3 years). Conclusion: TIPS and peritoneovenous shunts treat medically intractable ascites. Absence of ascites after either is uncommon. PV shunts control ascites sooner, although TIPS provides better long-term efficacy. After either shunt, numerous interventions are required to assist patency. Assisted shunt patency is better after TIPS. Treating medically refractory ascites with TIPS risks early shunt-related mortality for prospects of longer survival with ascites control. This study promotes the application of TIPS for medically intractable ascites if patients undergoing TIPS have prospects beyond short-term survival. PMID:15166968

Rosemurgy, Alexander S.; Zervos, Emmanuel E.; Clark, Whalen C.; Thometz, Donald P.; Black, Thomas J.; Zwiebel, Bruce R.; Kudryk, Bruce T.; Grundy, L Shane; Carey, Larry C.

2004-01-01

185

Embolization of splenorenal shunt associated to portal vein thrombosis and hepatic encephalopathy  

PubMed Central

Hepatic encephalopathy (HE) is a cognitive disturbance characterized by neuropsychiatric alterations. It occurs in acute and chronic hepatic disease and also in patients with portosystemic shunts. The presence of these portosystemic shunts allows the passage of nitrogenous substances from the intestines through systemic veins without liver depuration. Therefore, the embolization of these shunts has been performed to control HE manifestations, but the presence of portal vein thrombosis is considered a contraindication. In this presentation we show a cirrhotic patient with severe HE and portal vein thrombosis who was submitted to embolization of a large portosystemic shunt. Case report: a 57 years-old cirrhotic patient who had been hospitalized many times for persistent HE and hepatic coma, even without precipitant factors. She had a wide portosystemic shunt and also portal vein thrombosis. The abdominal angiography confirmed the splenorenal shunt and showed other shunts. The larger shunt was embolized through placement of microcoils, and the patient had no recurrence of overt HE. There was a little increase of esophageal and gastric varices, but no endoscopic treatment was needed. Since portosystemic shunts are frequent causes of recurrent HE in cirrhotic patients, portal vein thrombosis should be considered a relative contraindication to perform a shunt embolization. However, in particular cases with many shunts and severe HE, we found that one of these shunts can be safely embolized and this procedure can be sufficient to obtain a good HE recovery. In conclusion, we reported a case of persistent HE due to a wide portosystemic shunt associated with portal vein thrombosis. As the patient had other shunts, she was successfully treated by embolization of the larger shunt. PMID:25400477

Franzoni, Letícia de Campos; de Carvalho, Fábio Cardoso; Garzon, Rafael Gomes de Almeida; Yamashiro, Fábio da Silva; Augusti, Laís; Santos, Lívia Alves Amaral; Dorna, Mariana de Souza; Baima, Júlio Pinheiro; Lima, Talles Bazeia; Caramori, Carlos Antonio; Silva, Giovanni Faria; Romeiro, Fernando Gomes

2014-01-01

186

Partial versus total portacaval shunt in alcoholic cirrhosis. Results of a prospective, randomized clinical trial.  

PubMed Central

OBJECTIVE: Results of the first prospective randomized clinical trial comparing partial and total portacaval shunt for variceal hemorrhage are reported. SUMMARY BACKGROUND DATA: Total portacaval shunts produce subnormal portal pressures, completely diverting hepatic portal flow. Partial shunts maintain higher pressures and preserve hepatopedal flow. No randomized trials of these two approaches have been performed. METHODS: Alcoholic patients with cirrhosis (n = 30) and variceal hemorrhage treated at one institution were randomized to receive partial (8-mm diameter portacaval H grafts with collateral ablation, n = 14) or total shunts (16-mm diameter grafts, n = 16). Portography was performed after operation and then yearly. Investigators blinded to shunt type assessed encephalopathy; hospitalizations were reviewed. RESULTS: Child's class, age, and operative urgency were similar for the two groups. Two patients (with total shunts) died within 30 days. Hepatopedal flow was maintained in 13 partial and 0 total shunt patients (p < 0.0001). Shunt gradients were 16 +/- 5 compared with 6 +/- 3 cm saline after partial and total shunts (p < 0.0001). There were no shunt thromboses or variceal hemorrhages. Encephalopathy-free survival was significantly greater after partial shunts (p = 0.013; life table analysis). Five total compared with zero partial shunt patients required hospitalization for coma (p = 0.02). Long-term survival was not different for the two groups of patients. CONCLUSIONS: Partial shunts control variceal hemorrhage while maintaining hepatopedal flow and elevated portal pressures. By minimizing encephalopathy rates, partial shunts provide improved quality of survival compared with total shunts. Images Figure 1. Figure 2. Figure 3. Figure 4. PMID:8161260

Sarfeh, I J; Rypins, E B

1994-01-01

187

76 FR 81925 - Freeport LNG Development, L.P.; Notice of Application  

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2011-12-29

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2013-04-12

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2013-03-07

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2013-03-07

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2012-12-13

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2011-01-13

196

78 FR 17193 - Gulf South Pipeline Company, LP; Notice of Application  

Federal Register 2010, 2011, 2012, 2013, 2014

...2013, Gulf South Pipeline Company, LP (Gulf South), 9 Greenway Plaza, Suite 2800, Houston, Texas 77046, filed in Docket...Regulatory Affairs, Gulf South Pipeline Company, LP, 9 Greenway Plaza, Suite 2800, Houston, Texas 77046, or call...

2013-03-20

197

78 FR 1850 - Gulf South Pipeline Company, LP; Notice of Application for Abandonment  

Federal Register 2010, 2011, 2012, 2013, 2014

...2012, Gulf South Pipeline Company, LP (Gulf South), 9 Greenway Plaza, Suite 2800, Houston, TX 77046, filed in Docket No...Regulatory Affairs, at Boardwalk Pipeline Partners, LP, 9 Greenway Plaza, Suite 2800, Houston, TX 77046, telephone...

2013-01-09

198

76 FR 18748 - Gulf South Pipeline Company, LP; Notice of Application  

Federal Register 2010, 2011, 2012, 2013, 2014

...2011, Gulf South Pipeline Company, LP (Gulf South), 9 Greenway Plaza, Suite 2800, Houston, Texas 77046, filed in Docket...Regulatory Affairs, Gulf South Pipeline Company, LP, 9 Greenway Plaza, Suite 2800, Houston, Texas 77046, or by...

2011-04-05

199

75 FR 61480 - Gulf South Pipeline Company, LP; Notice of Request Under Blanket Authorization  

Federal Register 2010, 2011, 2012, 2013, 2014

...2010, Gulf South Pipeline Company, LP (Gulf South), 9 Greenway Plaza, Suite 2800, Houston, Texas 77046, filed a prior...Regulatory Affairs, Gulf South Pipeline Company, LP, 9 Greenway Plaza, Suite 2800, Houston, Texas 77046, telephone...

2010-10-05

200

76 FR 44902 - Gulf South Pipeline Company, LP; Notice of Request Under Blanket Authorization  

Federal Register 2010, 2011, 2012, 2013, 2014

...2011, Gulf South Pipeline Company, LP (Gulf South), 9 Greenway Plaza, Suite 2800, Houston, TX 77046, filed in Docket No...Regulatory Affairs, Gulf South Pipeline Company, LP, 9 Greenway Plaza, Suite 2800, Houston, TX 77046 at telephone...

2011-07-27

201

75 FR 40819 - Gulf South Pipeline Company, LP; Notice of Request Under Blanket Authorization  

Federal Register 2010, 2011, 2012, 2013, 2014

...June 23, 2010, Gulf South Pipeline Company, LP (Gulf), 9 Greenway Plaza, Suite 2800, Houston, Texas 77046, filed a prior...of Regulatory Affairs, Boardwalk Pipeline Partners, LP, 9 Greenway Plaza, Suite 2800, Houston, Texas 77046, by telephone...

2010-07-14

202

76 FR 22698 - Gulf South Pipeline Company, LP; Notice of Request Under Blanket Authorization  

Federal Register 2010, 2011, 2012, 2013, 2014

...2011, Gulf South Pipeline Company, LP (Gulf South), 9 Greenway Plaza, Suite 2800, Houston, Texas 77046, pursuant to its...Regulatory Affairs, Gulf South Pipeline Company, LP, 9 Greenway Plaza, Suite 2800, Houston, Texas 77046, at (713)...

2011-04-22

203

77 FR 69449 - Gulf South Pipeline Company, LP; Notice of Request Under Blanket Authorization  

Federal Register 2010, 2011, 2012, 2013, 2014

...2012, Gulf South Pipeline Company, LP (Gulf South), 9 Greenway Plaza, Suite 2800, Houston, TX 77046, filed in Docket No...Regulatory Affairs, Boardwalk Pipeline Partners, LP, 9 Greenway Plaza, Suite 2800, Houston, TX 77046 at telephone...

2012-11-19

204

76 FR 30326 - Gulf South Pipeline Company, LP; Notice of Application  

Federal Register 2010, 2011, 2012, 2013, 2014

...2011, Gulf South Pipeline Company, LP (Gulf South), 9 Greenway Plaza, Suite 2800, Houston, Texas 77046, filed an application...Regulatory Affairs, Gulf South Pipeline Company, LP, 9 Greenway Plaza, Suite 2800, Houston, Texas 77046, or by...

2011-05-25

205

77 FR 65680 - Gulf South Pipeline Company, L.P.; Notice of Request Under Blanket Authorization  

Federal Register 2010, 2011, 2012, 2013, 2014

...Gulf South Pipeline Company, L.P. (Gulf South), 9 Greenway Plaza, Suite 2800, Houston, Texas 77046, pursuant to the...Kyle Stephens, Gulf South Pipeline Company, L.P., 9 Greenway Plaza, Suite 2800, Houston, Texas 77046, (713)...

2012-10-30

206

"Tube-guided" implant of bioprosthetic shunt for hemodialysis.  

PubMed

Implant of a bovine-derived vascular bioprosthesis as arterio-venous shunt for hemodialysis may raise some problems regarding tunnel fashioning. Therefore, we have proposed a simple "tube-guided" technique to make implant safer and to avoid complications. PMID:11248176

Lanni, G; Napolitano, M M; Scala, A; De Rosa, P

2001-01-01

207

Microvascular Arteriovenous Shunting is a Probable Pathogenetic Mechanism in Erythromelalgia  

Microsoft Academic Search

Erythromelalgia is a condition consisting of red, warm, and burning painful extremities. Symptoms are relieved by cold and aggravated by heat. A wide variety of etiologic conditions can cause erythromelalgia, but one common pathogenetic mechanism, microvascular arteriovenous shunting, has been hypothesized. The aim of this study was to test this hypothesis. Quantification of skin microvascular perfusion using laser Doppler perfusion

Cato Mørk; Claes L. Asker; E. Goran Salerud; Knut Kvernebo

2000-01-01

208

PROOF-MASS INERTIAL VIBRATION CONTROL USING A SHUNTED  

E-print Network

PROOF-MASS INERTIAL VIBRATION CONTROL USING A SHUNTED ELECTROMAGNETIC TRANSDUCER Andrew J. Fleming-mass dampers utilize a suspended mass to reduce the vibration experienced by a host structure. Active vibration vibration absorbtion. An electrical impedance is designed and connected to an electromagnetic coil

Fleming, Andrew J.

209

Dynamics, stability, and control of multivariable piezoelectric shunts  

Microsoft Academic Search

This paper is concerned with the dynamics and stability of piezoelectric laminate structures, where several piezoelectric elements are shunted by a multiinput impedance. The problem is shown to be equivalent to a multivariable feedback control problem for a square plant. A parameterization of stabilizing admittance transfer function matrices is given together with a specific class of controllers capable of reducing

S. O. R. Moheimani; Andrew J. Fleming; Sam Behrens

2004-01-01

210

Inertial vibration control using a shunted electromagnetic transducer  

Microsoft Academic Search

Inertial drives and passive tuned-mass dampers utilize a suspended mass to reduce the vibration experienced by a host structure. Active vibration control systems typically include a voice coil type electromagnetic actuator to develop the required reaction forces. In this paper, the technique of sensorless active shunt control is applied to inertial vibration absorption. An electrical impedance is designed and connected

Andrew J. Fleming; S. O. Reza Moheimani

2006-01-01

211

Synthesis of optimal piezoelectric shunt impedances for structural vibration control  

Microsoft Academic Search

Piezoelectric transducers are commonly used as strain actuators in the control of mechanical vibration. One control strategy, termed piezoelectric shunt damping, involves the connection of an electrical impedance to the terminals of a structurally bonded transducer. Many passive, non-linear, and semi-active impedance designs have been proposed that reduce structural vibration. This paper introduces a new technique for the design and

Andrew J. Fleming; S. O. Reza Moheimani

2004-01-01

212

Synthesis of optimal piezoelectric shunt impedances for structural vibration control  

Microsoft Academic Search

Piezoelectric transducers are commonly used as strain actuators in the control of mechanical vibration. One control strategy, termed piezoelectric shunt damping, involves the connection of an electrical impedance to the terminals of a structurally bonded transducer. Many passive, non-linear, and semi-active impedance designs have been proposed that reduce structural vibration. This paper introduces a new technique for the design and

Andrew J. Fleming; S. O. Reza Moheimani

213

Passive piezoelectric shunt control of an Atomic Force Microscope microcantilever  

Microsoft Academic Search

When operating an Atomic Force Microscope (AFM) in tapping mode the quality (Q) factor of the cantilever probe places a limitation on scan speed and image resolution. This paper introduces piezoelectric shunt control as a new method of controlling the Q factor of a piezoelectric AFM microcantilever. Using this method the mechanical damping of the cantilever is controlled by an

Matthew W. Fairbairn; S. O. Reza Moheimani; Andrew J. Fleming

2011-01-01

214

Passive shunt damping of a piezoelectric stack nanopositioner  

Microsoft Academic Search

The speed and accuracy of nanopositioning systems is heavily influenced by the presence of lightly damped mechanical resonances. In this work, an electrical impedance is connected in series with the driving piezoelectric stack actuator to damp the first mechanical resonance. The electrical shunt is shown to act equivalently to an output feedback controller except that no sensor is required. A

Arnfinn Aas Eielsen; Andrew J. Fleming

2010-01-01

215

Congenital multiple intrahepatic portosystemic shunt: an autopsy case  

PubMed Central

Multiple intrahepatic portosystemic shunt (IPSS) without portal hypertension, now thought to be congenital in origin, is very rare. The presence of IPSS, unlike other congenital diseases, may not be recognized for several decades due to the time it takes to develop hepatic encephalopathy. In this article, we report an autopsy case of an 80-year-old Japanese woman with a one-month history of hyperammonemic encephalopathy. Radiological examination of the liver revealed some abnormal connections between the branches of the portal veins and the hepatic veins, but the cause of the aberrant blood flow was not found. The cause of death was extensive cerebral infarction due to thromboembolism. At postmortem examination, multiple anomalous blood vessels were identified histologically in both lobes of the non-cirrhotic liver. In comparison with the few similar cases existing in the literature, this case should be diagnosed as congenital IPSS. To our knowledge, this is the first detailed histological study of IPSS, as several autopsy case reports exist but their histological descriptions are poor. Unlike past reports, the shunt vessels were accompanied by clear elastic lamellae that were microscopically observed. In addition to shunt vessels, septal fibrosis, disorder of hepatic acinar structure, and sinusoidal dilatation and capillarization were observed in the liver. We suggest that these histological modifications observed in the circumference of the shunt vessels acted as secondary regenerative/hyperplastic changes based on blood-flow imbalance caused by the IPSS. PMID:24427367

Takahashi, Seishiro; Yoshida, Eriko; Sakanishi, Yasushi; Tohyama, Norihiro; Ayhan, Ayse; Ogawa, Hiroshi

2014-01-01

216

Mitigation of Acoustic Resonance using Electrically Shunted Loudspeakers  

E-print Network

Mitigation of Acoustic Resonance using Electrically Shunted Loudspeakers Andrew J. Fleminga impedance is connected to the terminals of an acoustic loudspeaker, the mechanical dynamics, and hence Vol. 6169 616918-1 #12;Figure 1. Experimental duct with two transversely mounted loudspeakers 2. S

Fleming, Andrew J.

217

Cerebrospinal fluid shunt infection due to Corynebacterium xerosis.  

PubMed

We report the case of a neonate who developed ventriculitis following insertion of a ventriculoperitoneal shunt. Corynebacterium xerosis was isolated from CSF and from the tip of the catheter after it was removed. The isolate was resistant to multiple antibiotics, but the infant responded to treatment with vancomycin. PMID:8089521

Gaskin, P R; StJohn, M A; Cave, C T; Clarke, H; Bayston, R; Levett, P N

1994-05-01

218

Optimal location of shunt FACTS devices for power flow control  

Microsoft Academic Search

Power flow control, in an existing long transmission line, plays a vital role in Power System area. This paper employs the shunt connected compensation (STATCOM) based FACTS device for the control of voltage and the power flow in long distance transmission line. The proposed device is used in different locations such as sending end of the transmission line, middle and

M. Karthikeyan; P. Ajay-D-Vimalraj

2011-01-01

219

Platelet function in dogs with congenital portosystemic shunt  

Microsoft Academic Search

The aim of this study was to examine the influence of congenital portosystemic shunts (CPSS) on primary haemostasis in dogs. Bleeding time, automated platelet function analysis (PFA 100 analyser), platelet count and platelet aggregation using different methods and agonists were measured in 10 dogs with untreated CPSS and in 10 healthy, age-matched controls.Bleeding time, platelet function analysis and platelet counts

K. Kalbantner; A. Meyer-Lindenberg; R. Mischke

2011-01-01

220

Liver arterialization improves hepatocytes ultrastructure in rats with portacaval shunts  

Microsoft Academic Search

The effect of arterialization (ART) of the distal stump of the portal vein after portacaval shunt (PCS) on bile formation and liver ultrastructure was assessed. ART using the left gastric artery was performed in male Wistar rats. Animals were sacrificed 3 weeks later. ART prevented body and liver atrophy. However, the liver weight to body weight ratio was significantly decreased

Jean Saric; Henri Faugon; Renaud Beliard; Jacques Perissat; Charles Balabaud; Liliane Dubuisson; Paulette Bioulac

1981-01-01

221

Giant perivascular spaces causing hemiparesis successfully treated by cystoventriculoperitoneal shunt.  

PubMed

We report a 55-year-old man affected by a slowly progressive hemiparesis. Imaging revealed giant dilations of brain perivascular spaces, or Virchow-Robin spaces of the thalamo-mesencephalic region and occlusive hydrocephalus. Stereotactic catheter cystoventriculostomy alone reverted hemiparesis. However, conversion of the catheter into a peritoneal shunt system was necessary to treat hydrocephalus. PMID:25232805

Roelz, Roland; Egger, Karl; Reinacher, Peter

2014-09-18

222

Shunt Revision by Coagulation with Retention of the Ventricular Catheter  

Microsoft Academic Search

Intraluminal coagulation of a ventricular catheter followed by its removal and replacement is a technique used for proximal shunt revision. The authors describe experience leaving the original catheter in place when flow of CSF is established by the coagulation. Advantages of this modification include maintenance of ventricular access when the ventricles are small and the possibility of reducing the incidence

Roger J. Hudgins; William R. Boydston

1998-01-01

223

Attenuation of Electromagnetic Interference in a Shunt Active Power Filter  

Microsoft Academic Search

Shunt active power filters (APF) are commonly used for the reduction of current harmonics and improvement of the power factor in power systems with nonlinear loads, such as diode rectifiers. A pulsewidth modulation (PWM) power converter constitutes the main component of the APF. The low-order harmonics of the line current are attenuated, but the switch-mode operation of the converter results

Konstantin Borisov; Herbert L. Ginn III; Andrzej M. Trzynadlowski

2007-01-01

224

Analysis of prognostic variables in the prediction of mortality, shunt failure, variceal rebleeding and encephalopathy following the transjugular intrahepatic protosystemic stent-shunt for variceal haemorrhage  

Microsoft Academic Search

Background\\/Aims: The aim of this study was to analyse prognostic variables predicting mortality, shunt insufficiency, variceal rebleeding and encephalopathy following transjugular intrahepatic portosystemic stent-shunt for variceal haemorrhage.Methods: Sixty-eight patients with cirrhosis who successfully underwent transjugular intrahepatic portosystemic stent-shunt for variceal haemorrhage were studied. Mean age was 54.8 years (s.e. 1.5); 41 were males and 27 were females. Mean Child score

Rajiv Jalan; Robert A. Elton; Doris N. Redhead; Niall D. C. Finlayson; Hayes Peter C

1995-01-01

225

Endovascular Intervention for Repositioning the Distal Catheter of Ventriculo-Atrial Shunt  

PubMed Central

Displacement of distal ventriculo-atrial (VA) shunt is not uncommon. However, misplacement of the distal catheter of VA shunt in the internal jugular vein is a possibility, especially when conducted without intraoperative monitoring. We describe a patient in whom a VA shunt was performed due to failure of ventriculo-peritoneal shunt and the distal catheter of the shunt was found to be misplaced in the left internal jugular vein. Endovascular intervention via femoral vein was used to retrieve the distal catheter. PMID:22970420

Xu, Botao; Chotai, Silky; Yang, Kaijun; Feng, Wenfeng; Zhang, Guozhong; Li, Mingzhou

2012-01-01

226

A new method for the measurement of intrahepatic shunts  

SciTech Connect

After transhepatic portal pressure determination, 96 patients were assessed for the presence of intrahepatic shunts by injection of microspheres (25 +/- 5 micron diameter) into the portal vein using RISA-131I as an indicator of dilution. Multiple portal vein injections in each patient allowed blood sampling from the hepatic vein (site 1) and from two inferior vena cava sampling sites (site 2, at the junction of the hepatic vein orifice with the inferior vena cava, and site 3, 2 to 3 cm closer to or within the right atrium). Intrahepatic shunting was calculated from each site: hepatic vein in 57 patients and inferior vena cava, site 2 in 43 patients and site 3 in 77 patients. At least one valid IHS calculation was available in 92 of the patients. Intrahepatic shunting calculated from sequential portal vein injections with sampling from the hepatic vein was highly correlated (r . 0.98, p less than 0.0001, slope . 1.0), with a mean difference of 1.9% +/- 1.9%. There was no significant difference by t test comparison of the mean IHS calculated from sites 1, 2, and 3. Occasional marked discrepancies were noted between IHS calculated from site 1 or site 2 compared with site 3, and the site 3 calculation was always greater. A shunt index in all patients included shunts calculated from the hepatic vein in 57 patients plus shunt calculation from the inferior vena cava in the remaining patients (site 2 in 26 patients and site 3 in nine). The 82 patients with portal hypertension or chronic liver disease had a higher portal pressure, 13.8 +/- 4.6 mm Hg, and a significantly greater shunt index, 13.7% +/- 24.5% compared with controls. The frequency distribution of IHS in patients with chronic liver disease demonstrated less than 2% IHS in 49% of patients and less than 5% IHS in 63%. The validity of our methods and the implications of the infrequent demonstration of a large IHS are discussed.

Hoefs, J.C.; Reynolds, T.B.; Pare, P.; Sakimura, I.

1984-03-01

227

Fire Service Training. LP and Compressed Gas Emergencies.  

ERIC Educational Resources Information Center

Part of a series of instructional outlines intended for use in a training program for firemen with no previous formal training, this curriculum guide discusses safety precautions for liquefied petroleum (LP) and compressed gas emergencies. During its twelve hours of instruction it covers (1) terminology; (2) the chemical composition of the gases;…

North Carolina State Dept. of Community Colleges, Raleigh.

228

US EPA Testing of LP & MP UV Disinfection Technologies  

EPA Science Inventory

Presentation will discuss the ongoing USEPA research on UV disinfection addressing the following objectives: Conservatively predict log inactivation and RED of adenovirus with surrogates; Conduct many (LP=61) UV reactor conditions challenged with Ad2, B. pumilus, and MS2 & conduc...

229

LP Decoding Corrects a Constant Fraction of Errors  

Microsoft Academic Search

We show that for low-density parity-check (LDPC) codes whose Tanner graphs have sufficient expansion, the linear programming (LP) decoder of Feldman, Karger, and Wainwright can correct a constant fraction of errors. A random graph will have sufficient expansion with high probability, and recent work shows that such graphs can be constructed efficiently. A key element of our method is the

Jon Feldman; Tal Malkin; Rocco A. Servedio; Clifford Stein; Martin J. Wainwright

2007-01-01

230

Strong spatial Lp error estimates in computing the  

E-print Network

Field following Chen [1994] Phase transition in solidification process u - u + (u3 - u)/ = w. Phase-field models of phase separation and geometric motions Rubinstein et al. [1989], Evans et al-life dendrite lab picture: A phase-field simulation: Omar Lakkis (Sussex) Strong Lp estimates in computing

Lakkis, Omar

231

Load Balancing in the Lp Norm Baruch Awerbuch Yossi Azary  

E-print Network

Load Balancing in the Lp Norm Baruch Awerbuch Yossi Azary Edward F. Grovez Dept. of Computer@cs.duke.edu Abstract In the load balancing problem, there is a set of servers, and jobs arrive sequentially. Each job of jobs to servers is quanti ed by the maximum load assigned to any server. In this measure

Azar, Yossi

232

The Application of Controlled Intracranial Hypertension in Slit Ventricle Syndrome Patients with Obstructive Hydrocephalus and Shunt Malfunction  

Microsoft Academic Search

When a shunted patient with slit-ventricle syndrome (SVS) presents with a shunt malfunction or infection, the third ventricle may not be of sufficient caliber, despite the shunt malfunction, to allow atraumatic passage of an endoscope to the floor of the third ventricle. We describe four slit ventricle syndrome patients with respectively 24, 12, 18 and 2 prior shunt revisions who

William E. Butler; Saad A. Khan

2001-01-01

233

Management of surgical splenorenal shunt-related hepatic myelopathy with endovascular interventional techniques  

PubMed Central

We present a case with hepatic myelopathy (HM) due to a surgical splenorenal shunt that was successfully treated by endovascular interventional techniques. A 39-year-old man presented with progressive spastic paraparesis of his lower limbs 14 mo after a splenorenal shunt. A portal venogram identified a widened patent splenorenal shunt. We used an occlusion balloon catheter initially to occlude the shunt. Further monitoring of the patient revealed a decrease in his serum ammonia level and an improvement in leg strength. We then used an Amplatzer vascular plug (AVP) to enable closure of the shunt. During the follow up period of 7 mo, the patient experienced significant clinical improvement and normalization of blood ammonia, without any complications. Occlusion of a surgically created splenorenal shunt with AVP represents an alternative therapy to surgery or coil embolization that can help to relieve shunt-induced HM symptoms. PMID:23323015

Wang, Mao-Qiang; Liu, Feng-Yong; Duan, Feng

2012-01-01

234

29 CFR 1926.153 - Liquefied petroleum gas (LP-Gas).  

Code of Federal Regulations, 2011 CFR

... 2011-07-01 false Liquefied petroleum gas (LP-Gas). 1926.153 Section...Prevention § 1926.153 Liquefied petroleum gas (LP-Gas). (a) Approval of...for transportation or storing liquefied petroleum gases. (b) Welding on LP-Gas...

2011-07-01

235

29 CFR 1926.153 - Liquefied petroleum gas (LP-Gas).  

Code of Federal Regulations, 2013 CFR

... 2013-07-01 false Liquefied petroleum gas (LP-Gas). 1926.153 Section...Prevention § 1926.153 Liquefied petroleum gas (LP-Gas). (a) Approval of...for transportation or storing liquefied petroleum gases. (b) Welding on LP-Gas...

2013-07-01

236

29 CFR 1926.153 - Liquefied petroleum gas (LP-Gas).  

Code of Federal Regulations, 2014 CFR

... 2014-07-01 false Liquefied petroleum gas (LP-Gas). 1926.153 Section...Prevention § 1926.153 Liquefied petroleum gas (LP-Gas). (a) Approval of...for transportation or storing liquefied petroleum gases. (b) Welding on LP-Gas...

2014-07-01

237

29 CFR 1926.153 - Liquefied petroleum gas (LP-Gas).  

Code of Federal Regulations, 2012 CFR

... 2012-07-01 false Liquefied petroleum gas (LP-Gas). 1926.153 Section...Prevention § 1926.153 Liquefied petroleum gas (LP-Gas). (a) Approval of...for transportation or storing liquefied petroleum gases. (b) Welding on LP-Gas...

2012-07-01

238

Insulin sensitivity and Lp(?) concentrations in normoglycemic offspring of type 2 diabetic parents  

Microsoft Academic Search

BACKGROUND: Offspring of at least 1 parent with type 2 diabetes are more resistant to the insulin action, exhibit higher incidence of dyslipidemia and are more prone to cardiovascular diseases. The association between Lp(?) and coronary heart disease is well established. An association between Lp(?) concentration and insulin sensitivity was examined in this study. We investigated the serum LP(?) in

Agathoklis Psyrogiannis; Ioannis Habeos; Venetsana Kyriazopoulou

2003-01-01

239

Hierarchical Modeling of Local Image Features through Lp-Nested Symmetric Distributions  

E-print Network

in terms of a hierarchical cascade of Lp- norms. This class generalizes the family of spherically and Lp-spherically sym- metric distributions which have recently been successfully used for natural im- age modeling. By fit- ting the generalized Lp-nested model to 8 × 8 image patches, we show that the subspaces obtained

Simoncelli, Eero

240

Shunt implantations and peritoneal catheters: Do not cut beyond 20 cm  

PubMed Central

Background: Ventriculoperitoneal shunts are supplied with long peritoneal catheters, most commonly between 80 and 120 cm long. ISO/DIS 7197/2006[15] shunt manufacturing procedures include peritoneal catheter as an integrate of the total resistance. Cutting pieces of peritoneal catheters upon shunt implantation or revision is a common procedure. Methods: We evaluated five shunts assembled with different total pressure resistances and variable peritoneal catheter lengths in order to clarify the changes that occurred in the hydrodynamic profile when peritoneal catheters were cut upon shunt implantation or shunt revision. Results: Originally, all shunts performed within the operational range. Shunt 1 performed in a lower pressure range at 200 mm cut off peritoneal catheter and as a low-pressure shunt with –300 mm cut off. Shunt 2 was manufactured to run at the higher border pressure range, and it went out of specification with a 300 mm cut off. Shunt 3 was manufactured to run close to the lower border pressure range, and at 100 mm cutoff, it was already borderline in a lower resistive category. Other shunts also responded similarly. Conclusion: The limit to maintain a shunt in its original pressure settings was 20 cm peritoneal catheter cutting length. By cutting longer pieces of peritoneal catheter, one would submit patients to a less-resistive regimen than intended and his reasoning will be compromised. The pediatric population is more prone to suffer from the consequences of cutting catheters. Shunt manufacturers should consider adopting peritoneal catheters according to the age (height) of the patient. PMID:25250184

Maset, Angelo Luiz; Suriano, ?talo Capraro; Monteiro, Ruy; Pinto, José Ricardo Camilo; de Andrade, José Ricardo; Mancini, Bruna Monieli; Ramin, Sérgio Luiz; Moraes, Dionei Freitas; Cavalheiro, Sérgio

2014-01-01

241

Association of freezing tolerance to LpCBFIIIb and LpCBFIIIc gene polymorphism in perennial ryegrass accessions  

Technology Transfer Automated Retrieval System (TEKTRAN)

CBF/DREB related genes are considered important genes for regulation of abiotic stress in plants. In this study, CBF/DREB genes in perennial ryegrass (Lolium perenne L.), also known as LpCBF genes, were resequenced from several cultivated and landrace plants from a worldwide collection. The same pla...

242

78 FR 53745 - Gulf South Pipeline Company, LP; Petal Gas Storage, L.L.C.; Gulf South Pipeline Company, LP...  

Federal Register 2010, 2011, 2012, 2013, 2014

...application may be directed to J. Kyle Stephens, Vice President of Regulatory Affairs, Boardwalk Pipeline Partners, LP, 9 Greenway Plaza, Houston, Texas, 77046; by fax 713-479- 1846 or email to kyle.stephens@bwpmlp.com. There are two ways...

2013-08-30

243

The orbital volume measurement in patients with ventriculoperitoneal shunt.  

PubMed

Enophthalmos occurs from the increased bony volume or decreased soft tissue volume in the orbit and can be caused in patients with long-term ventriculoperitoneal (VP) shunt. This study tried to find out the change of orbital volume by measuring the orbital volume before and after operation in adult patients who underwent VP shunt for hydrocephalus. The 2 evaluators measured orbital volume by using ITK-SNAP 2.4 program with double-blind test for computed tomography images before and after operation targeting 36 patients over the age of 18 who underwent VP shunt with pressure-controlled valve from 2003 to 2011. Wilcoxon matched-pairs signed-rank test of GraphPad software was used to statistically analyze the difference in orbital volume change before and after operation. In case of mean pre-op orbital volume of total 36 patients, the right was measured as 23.72 ± 4.65 cm(3), the left as 23.47 ± 4.61 cm(3), the post-op right as 24.67 ± 4.70 cm(3), and the left as 24.18 ± 4.63 cm(3), showing no statistically significant difference (P = 0.106). The mean pre-op orbital volume of 14 people (28 eyes) followed for more than 11 months was 25.06 ± 4.58 cm(3) in the right and 24.4 ± 5.02 cm(3) in the left and the mean post-op orbital volume was 27.0 ± 4.28 cm(3) in the right and 25.76 ± 3.92 cm(3) in the left, showing statistically significant differences in the change of the volume before and after shunt operation (P = 0.0057). In patients who maintain long-term shunt devices after VP shunt, remodeling of matured orbital bone may be caused due to the change in pressure gradient between cranial cavity and orbit and the possible occurrence of resulting secondary enophthalmos by increased orbital volume should be considered. PMID:25490570

Kim, Jong-Min; Chang, Moo-Hwan; Kyung, Sungeun E

2015-01-01

244

Post-Shunt Resource Consumption Favors Small-Diameter Prosthetic H-Graft Portacaval Shunt Over TIPS for Patients With Poor Hepatic Reserve  

PubMed Central

Objective To define the role of surgical shunting for patients with poor hepatic reserve (Child’s class C) in the era of TIPS. Summary Background Data Most physicians prefer TIPS to surgical shunting for patients with poor hepatic reserve because of anticipated poor long-term survival. Methods Sixty-two patients of Child’s class C with bleeding varices not amenable to endoscopic sclerotherapy or banding were prospectively randomized to undergo TIPS or 8-mm prosthetic H-graft portacaval shunt (HGPCS) from 1993 to 1999. Resource consumption and survival after shunting were determined. Results Twenty-nine patients underwent TIPS and 33 underwent HGPCS. After HGPCS, survival at 3 years was favorable but not statistically superior. TIPS was more often associated with shunt stenoses/occlusions, recurrent hemorrhage, shunt revisions, and shunt failure. Long-term follow-up documented that after HGPCS, patients required fewer hospital and ICU days and fewer units of RBCs transfused. After HGPCS, cost of care was less, as was the median cost of care per day of survival. Conclusions For Child’s class C patients undergoing HGPCS or TIPS, long-term survival is similar, though favoring HGPCS. Similarly, measures of resource consumption and cost of care following hospital discharge favor HGPCS. HGPCS should be preferentially applied for acceptable patients without access to convenient capable post-shunt care or without definitive plans for imminent transplantation. PMID:12796578

Rosemurgy, Alexander S.; Zervos, Emmanuel E.; Bloomston, Mark; Durkin, Alan J.; Clark, Whalen C.; Goff, Stephanie

2003-01-01

245

Upward Migration of a Peritoneal Catheter Following Ventriculoperitoneal Shunt  

PubMed Central

We present an unusual case of peritoneal catheter migration following a ventriculoperitoneal shunt operation. A 7-month-old infant, who had suffered from intraventricular hemorrhage at birth, was shunted for progressive hydrocephalus. The peritoneal catheter, connected to an 'ultra small, low pressure valve system' (Strata®; PS Medical,Gola, CA, USA) at the subgaleal space, was placed into the peritoneal cavity about 30 cm in length. The patient returned to our hospital due to scalp swelling 21 days after the surgery. Simple X-ray images revealed total upward migration and coiling of the peritoneal catheter around the valve. Possible mechanisms leading to proximal upward migration of a peritoneal catheter are discussed. PMID:24003378

Cho, Kyung Rae; Yeon, Je Young

2013-01-01

246

Cavum septi pellucidi as a cause of shunt dysfunction.  

PubMed

Cavum septi pellucidi and cavum vergae are generally asymptomatic fluid collections between the leaves of the septum pellucidum and are present in approximately 15% of adult brains. There are occasional reported cases of symptomatic cysts arising in this area. This paper reports a case in which a cavum septi pellucidi was a cause of shunt malfunction. On an air ventriculogram this condition was initially confused with a subdural collection. PMID:6974410

Mapstone, T B; White, R J

1981-08-01

247

Improved Shunt Active Power Compensator for IEEE Standard 1459 Compliance  

Microsoft Academic Search

This paper presents the simulated and experimental results of an improved shunt active power compensator (SAPC). The proposed power compensator achieves IEEE Standard 1459 compliance by using moving-window discrete Fourier transform (DFT) calculations to obtain reference currents, and a time-efficient current regulator. The current regulator is based on the analysis of the per-phase electrical model of the (APC). The main

S. Orts-Grau; F. J. Gimeno-Sales; A. Abella?n-Garci?a; S. Segui?-Chilet; J. C. Alfonso-Gil

2010-01-01

248

Cardiac Perforation and Tamponade During Transjugular Intrahepatic Portosystemic Shunt Placement  

SciTech Connect

A patient developed acute severe hemodynamic compromise during a transjugular intrahepatic portosystemic shunt (TIPS) procedure for intractable ascites. Rapid clinical and radiographic evaluation of the patient disclosed pericardial blood and cardiac tamponade as the cause, probably due to right heart perforation from guidewire and catheter manipulation. The tamponade was successfully treated percutaneously, and the patient survived. Cardiac tamponade should be considered in the differential diagnosis of patients who develop hypotension during TIPS placement.

McCowan, Timothy C. [Department of Radiology, University of Arkansas for Medical Sciences, 4301 West Markham, Little Rock, AR 72205 (United States); Hummel, Michael M. [Radiologists of North Iowa, Mason City, IA 50401 (United States); Schmucker, Tracey [Department of Ophthalmology, University of Arkansas for Medical Sciences, 4301 West Markham, Little Rock, AR 72215 (United States); Goertzen, Timothy C.; Culp, William C.; Habbe, Thomas G. [Department of Radiology, University of Nebraska Medical Center, 981045 Nebraska Medical Center, Omaha, NE 68198-1045 (United States)

2000-07-15

249

Transjugular intrahepatic portosystemic shunt (TIPSS) for Budd Chiari syndrome.  

PubMed

We report a four year old boy who presented with liver failure secondary to anti-thrombin III deficiency related Budd Chiari syndrome. He was treated with TIPSS (transjugular intrahepatic porto systemic shunt) which reversed the encephalopathy, normalised the liver function and improved growth, pre-empting the need for a liver transplantation. This is the first reported case of TIPSS in a child with a fulminant presentation of Budd-Chiari Syndrome. PMID:20622284

Hasija, R P; Nagral, A; Marar, S; Bavdekar, A R

2010-06-01

250

Outcome of pregnancy in women with congenital shunt lesions  

Microsoft Academic Search

OBJECTIVETo evaluate the outcome of pregnancy in women with congenital shunt lesions.SETTINGRetrospective study in a tertiary care centre.METHODSPregnancy history was obtained by a standardised questionnaire and medical records were reviewed.PATIENTS175 women were identified, at a mean (SD) age of 42 (14) years. Pregnancies occurred in 126 women: 50 with an atrial septal defect, 22 with a ventricular septal defect, 22

M Zuber; N Gautschi; E Oechslin; V Widmer; W Kiowski; R Jenni

1999-01-01

251

LP-VIcode: La Plata Variational Indicators Code  

NASA Astrophysics Data System (ADS)

LP-VIcode computes variational chaos indicators (CIs) quickly and easily. The following CIs are included: Lyapunov Indicators, also known as Lyapunov Characteristic Exponents, Lyapunov Characteristic Numbers or Finite Time Lyapunov Characteristic Numbers (LIs) Mean Exponential Growth factor of Nearby Orbits (MEGNO) Slope Estimation of the largest Lyapunov Characteristic Exponent (SElLCE) Smaller ALignment Index (SALI) Generalized ALignment Index (GALI) Fast Lyapunov Indicator (FLI) Orthogonal Fast Lyapunov Indicator (OFLI) Spectral Distance (SD) dynamical Spectra of Stretching Numbers (SSNs) Relative Lyapunov Indicator (RLI)

Carpintero, Daniel; Darriba, Luciano; Maffione, Nicolás

2015-01-01

252

Autoregressive model in the Lp norm space for EEG analysis.  

PubMed

The autoregressive (AR) model is widely used in electroencephalogram (EEG) analyses such as waveform fitting, spectrum estimation, and system identification. In real applications, EEGs are inevitably contaminated with unexpected outlier artifacts, and this must be overcome. However, most of the current AR models are based on the L2 norm structure, which exaggerates the outlier effect due to the square property of the L2 norm. In this paper, a novel AR object function is constructed in the Lp (p?1) norm space with the aim to compress the outlier effects on EEG analysis, and a fast iteration procedure is developed to solve this new AR model. The quantitative evaluation using simulated EEGs with outliers proves that the proposed Lp (p?1) AR can estimate the AR parameters more robustly than the Yule-Walker, Burg and LS methods, under various simulated outlier conditions. The actual application to the resting EEG recording with ocular artifacts also demonstrates that Lp (p?1) AR can effectively address the outliers and recover a resting EEG power spectrum that is more consistent with its physiological basis. PMID:25448380

Li, Peiyang; Wang, Xurui; Li, Fali; Zhang, Rui; Ma, Teng; Peng, Yueheng; Lei, Xu; Tian, Yin; Guo, Daqing; Liu, Tiejun; Yao, Dezhong; Xu, Peng

2015-01-30

253

Chemoembolic Hepatopulmonary Shunt Reduction to Allow Safe Yttrium-90 Radioembolization Lobectomy of Hepatocellular Carcinoma  

SciTech Connect

Yttrium-90 ({sup 90}Y) radioembolization represents an emerging transcatheter treatment option for the management of hepatocellular carcinoma (HCC). Elevation of the hepatopulmonary shunt fraction risks nontarget radiation to the lungs and may limit the use of {sup 90}Y therapy in patients with locally advanced disease with vascular invasion, who often demonstrate increased shunting. We present two cases in which patients with HCC and portal vein invasion resulting in elevated hepatopulmonary shunt fractions underwent chemoembolic shunt closure to allow safe {sup 90}Y radioembolization. Both patients demonstrated excellent tumor response and patient survival. On this basis, we propose a role for chemoembolic reduction of the lung shunt fraction before {sup 90}Y radioembolization in patients with extensive tumor-related hepatopulmonary shunting.

Gaba, Ron C., E-mail: rgaba@uic.edu [University of Illinois Medical Center at Chicago, Department of Radiology, Section in Interventional Radiology (United States); VanMiddlesworth, Kyle A. [Midwestern University School of Medicine (United States)

2012-12-15

254

Development of chronic hepatocerebral degeneration eight years after a distal splenorenal (Warren) shunt.  

PubMed Central

It is well known that chronic encephalopathy may be a major complication after the establishment of a surgical portal caval shunt for an episode of variceal haemorrhage. In an effort to minimise this problem Warren and colleagues developed the distal splenorenal shunt where the portal and mesenteric blood flow to the liver was left intact. It is now recognised, however, that the longterm incidence of encephalopathy may be no different with this type of shunt compared with conventional surgical portal systemic shunts. Acquired chronic hepatocerebral degeneration has not been reported after such a selective shunt. A patient with primary biliary cirrhosis is reported who developed the clinical features of this syndrome eight years after a successful distal splenorenal shunt. Images Fig. 1 Fig. 2 PMID:2583570

Bleasel, A F; Waugh, R C; McCaughan, G W

1989-01-01

255

Post Blalock-Taussig shunt mediastinal mass - a single shadow with two different destinies.  

PubMed

The modified Blalock-Taussig shunt is a synthetic shunt between the subclavian and pulmonary artery, used in the treatment of congenital cyanotic heart diseases with pulmonary hypoperfusion. Delayed complications include progressive failure of the shunt, serous fluid leak, and pseudoaneurysm formation. We report two different and rare mediastinal vascular complications following modified BT shunt surgery in this case report. The first one is a seroma, due to serous fluid leakage through the shunt graft, which is a relatively benign complication. The second one is a pseudoaneurysm, arising from the shunt, a frequently fatal complication. Generally, X-ray chest is used for screening in these patients. CT angiography plays a vital role in the diagnosis of both these conditions. Management in pseudoaneurysm should be aggressive, as timely intervention may be life saving, while in seroma the management is most often conservative occasionally requiring surgical intervention. PMID:24814123

Rohit, Manoj Kumar; Vadivelu, Ramalingam; Khandelwal, Niranjan; Krishna, Satheesh

2014-01-01

256

Reversibility of intrapulmonary arteriovenous shunts in liver cirrhosis documented by serial radionuclide perfusion lung scans  

SciTech Connect

Using serial perfusion lung scans, the opening up and closure of right-to-left intrapulmonary arteriovenous shunts has been documented over a period of several weeks in a patient with chronic alcoholic liver disease. The presence of the shunts correlates well with the severity of hypoxemia and the presence of nodular mottling on chest radiographs. The time course of these changes with clinical status suggests lability and the functional nature of these shunts.

Chen, N.S.; Barnett, C.A.; Farrer, P.A.

1984-05-01

257

Measurements of differential group delay and chromatic dispersion for LP01 and LP11 modes of few-mode fibers with depressed claddings  

NASA Astrophysics Data System (ADS)

The chromatic dispersion of the LP11 mode in a few-mode fiber with low differential group delay is evaluated experimentally. A differential group delay of less than 100 ps/km around 1550 nm can be evaluated with the modal interferometer method. The white-light interferometric method confirms that the LP11 mode is behind the LP01 mode in the 1300-1600 nm wavelength region. The difference between the chromatic dispersion values of the two modes is less than 0.5 ps/km/nm, which means that the optical pulse spreading characteristics of the LP11 mode are similar to those of the LP01 mode for fibers with depressed claddings.

Shibata, Nori; Ohashi, Masaharu; Maruyama, Ryo; Kuwaki, Nobuo

2015-02-01

258

Simultaneous urethrocutaneous and urethrocavernous fistula after proximal corporospongiosal shunt for priapism.  

PubMed

Proximal corporospongiosal shunts are used for the most refractory cases of priapism. Here, we present the case of a 58-year-old man whose priapism was only partially responsive to phenylephrine injections and distal shunting. Proximal shunting was required, and he subsequently developed fistulization of the proximal penile urethra into the skin and the corpora cavernosa. The formation of simultaneous urethrocutaneous and urethrocavernous fistulae is a rare complication of proximal corporospongiosal shunts that can be initially managed with urinary diversion with a suprapubic tube. PMID:25733307

Manjunath, Adarsh S; Mazur, Daniel J; Han, Justin S; Gonzalez, Christopher M

2015-03-01

259

Thrombosed Mesocaval Shunt: Salvage by Mechanical Thrombolysis. Case Report and Review of the Literature  

SciTech Connect

We report the case of a 27-year-old male who presented with acute mesocaval shunt thrombosis, which was successfully managed by mechanical thrombolysis. Shunt thrombosis was suspected when the patient showed clinical signs and symptoms of obstructive jaundice in the immediate postoperative period. Doppler sonography showed absence of flow across the shunt, suggestive of thrombosis, which was mechanically thrombolyzed by a percutaneous approach. The portocaval pressure gradient noted at the end of procedure was <5 mm Hg. The shunt remained patent at the end of 3 months' follow-up.

Baijal, Sanjay Saran, E-mail: ssbaijal@sgpgi.ac.in; Mohan, Suyash; Singh, Jagadeesh R.; Verma, Ashish [Sanjay Gandhi Postgraduate Institute of Medical Sciences, Department of Radiodiagnosis (India)

2008-07-15

260

Embolization of portal-systemic shunts in cirrhotic patients with chronic recurrent hepatic encephalopathy  

SciTech Connect

Purpose. To evaluate the efficacy of embolization of portal-systemic shunts in cirrhotic patients with chronic recurrent hepatic encephalopathy (CRHE). Methods. Seven cirrhotic patients with CRHE refractory to medical treatment (3 men and 4 women, mean age 66 years) were studied. Five patients had splenorenal shunts, 1 had a gastrorenal shunt, and 1 had an intrahepatic portal vein-hepatic vein shunt. Shunt embolization was performed using stainless steel coils, with a percutaneous transhepatic portal vein approach in 4 patients and a transrenal vein approach in 3 patients. Results. After embolization, the shunt disappeared in 4 patients on either ultrasound pulsed Doppler monitoring or portography. Complications observed in the 7 patients were fever, transient pleural effusion, ascites, and mild esophageal varices. For 3-6 months after embolization, the 4 patients whose shunts disappeared showed minimal or no reappearance of a shunt, and had no recurrence of encephalopathy. The serum ammonia levels decreased and electroencephalograms also improved. One of the 4 patients, who developed mild esophageal varices, required no treatment. Treatment was effective in 3 of the 4 patients (75%) who underwent embolization via a transhepatic portal vein. Conclusion. Transvascular embolization of shunts improved the outcome in 4 of 7 patients. The most effective embolization was achieved via the percutaneous transhepatic portal vein approach.

Sakurabayashi, Shin; Sezai, Shuichi; Yamamoto, Yoshihiro; Hirano, Masanori; Oka, Hiroshi [Tokyo Metropolitan Police Hospital, Division of Gastroenterology (Japan)

1997-03-15

261

Splenic transposition is superior to caudal shunt as a model of murine total hepatic ischemia.  

PubMed

Murine total hepatic ischemia (THI) followed by reperfusion without shunting of the portal vein induces significant lethality in rodents due to intestinal congestion. Two methods have been promulgated to study THI and reperfusion in mice without intestinal congestion: subcutaneous splenic transposition which creates a portosystemic shunt via epigastric vessels, and a caudal shunt with 30% hepatectomy, which creates a portosystemic shunt via the small remnant of remaining caudal lobe. We compared outcome, inflammatory response and hepatic injury due to THI and reperfusion in these two models. Female C57BL/6 mice underwent ST, caudal shunt or no surgery prior to having 30 min of total hepatic ischemia followed by 60 min of reperfusion. Survival, surgical complications, serum AST/ALT and IL-6 were determined. Apoptotic and necrotic hepatocytes were identified by morphological criteria. Complication rates for the ST and caudal shunt procedures were 6.7 and 20%, respectively. Subsequent mortality rates following THI and 60 min reperfusion were 5.9 and 50% in mice with ST and caudal shunt, respectively. Both groups had elevated serum AST/ALT concentrations. However, in mice undergoing caudal shunt, AST/ALT levels were also significantly increased even without THI. The number of apoptotic hepatocytes after THI and reperfusion in mice following caudal shunt was significantly higher compared with those of ST (P<0.001). Both ST and caudal shunt can be used in models of THI and reperfusion to prevent significant lethality due to intestinal congestion. However, ST is a simple, safe and suitable model, whereas caudal shunt requires manipulation of the liver, and is associated with significant hepatic injury and morbidity. PMID:15558060

Matsumoto, Tadashi; Efron, Philip A; Tsujimoto, Hironori; Tschoeke, Sven K; Ungaro, Ricardo; Fujita, Shiro; Foley, David P; Hemming, Alan; Moldawer, Lyle L

2005-01-01

262

Radiographic assessment of snap-shunt failure: report of 2 cases.  

PubMed

Accurate assessment of imaging studies in patients with ventriculoperitoneal shunts can be aided by empirical findings. The authors characterize an objective measurement easily performed on head CT scans with the goal of producing clear evidence of shunt fracture or disconnection in patients with a snap shunt-type system. The authors describe 2 cases of ventriculoperitoneal shunt failure involving a fracture and a disconnection associated with a snap-shunt assembly. In both cases the initial clinical symptoms were not convincing for shunt malfunction, and the interpretation of the CT finding failed to immediately identify the abnormality. As the clinical picture became more convincing for shunt malfunction, each patient subsequently underwent successful shunt revision. The authors reviewed the CT scans of 10 patients with an intact and functioning snap-shunt system to characterize the normal appearance of the snap-shunt connection. On CT scans the distance between the radiopaque portion of the ventricular catheter and the radiopaque portion of the reservoir dome measures an average of 4.72 mm (range 4.6-4.9 mm, 95% CI 4.63-4.81 mm). In the authors' patient with a fractured ventricular catheter, this interval measured 7.8 mm, and in the patient with a disconnection it measured 7.7 mm. In comparison with the range of normal values, a radiolucent interval significantly greater than 4.9 mm should promptly raise concern for a disconnected or fractured shunt in this system. This measurement may prove particularly useful when serial imaging is not readily available. PMID:20809717

Rughani, Anand I; Tranmer, Bruce I; Florman, Jeffrey E; Wilson, James T

2010-09-01

263

Capstone Low Pressure Grid-connect Tests Capstone LP Stand-alone Tests  

E-print Network

Appendix B Capstone Low Pressure Grid-connect Tests 10/25/2000 #12;Capstone LP Stand-alone Tests 10) Figure B-1: Power and Shaft Speed ­ 10 kW Steps #12;Capstone LP Stand-alone Tests 10/25/2000 0 5000 10000) Figure B-2: Power and Turbine Exit Temperature ­ 10 kW Steps #12;Capstone LP Stand-alone Tests 10

264

Emergency portosystemic shunt in patients with variceal bleeding.  

PubMed

Thirty-five patients for whom emergency sclerotherapy or conservative treatment, or both, failed to arrest variceal bleeding, or who had early rebleeding and required emergency portosystemic shunts (EPSS) were studied. EPSS permanently controlled the variceal bleeding in all but one patient. In this patient, the shunt was patent as demonstrated by angiography. Esophageal varices disappeared in 18 patients and were reduced in 14. Three patients died before the endoscopic examination could be performed. The causes of death were hepatic failure in two and bleeding ulcerations of the gastric fundus in the other patient. One patient was classified in Child's category B and two in Child's category C. Thirty-two patients submitted to EPSS and were discharged alive. Twelve of these patients subsequently died, at an average of 11.2 months after undergoing the shunt procedure. Four of 12 patients died of hepatic failure; two patients died of hepatomas; two, other neoplasia; three, hemorrhaging duodenal ulcers, and one patient, renal failure. Analysis of actuarial survival rates showed that the five year survival rate was 43 per cent. The long term survival rates were fewer for patients with Child's category C than for those with combined Child's categories A and B (five year survival rates were 21 versus 55 per cent; p less than 0.05). During the follow-up period, none of the patients had variceal bleeding. Chronic encephalopathy developed in six, which was mild in three, moderate in one instance and severe in two. It developed soon after EPSS, with onset in the first month after discharge in three. Thus, when conservative treatment fails to arrest variceal bleeding, EPSS should be performed to guarantee definitive control of hemorrhage and prolong the survival period. PMID:2244277

Spina, G P; Santambrogio, R; Opocher, E; Gagliano, G; Cucchiaro, G; Pisani, A; Macri, M

1990-12-01

265

EBNA-LP Associates with Cellular Proteins Including DNA-PK and HA95  

PubMed Central

EBNA-LP-associated proteins were identified by sequencing proteins that immunoprecipitated with Flag epitope-tagged EBNA-LP (FLP) from lymphoblasts in which FLP was stably expressed. The association of EBNA-LP with Hsp70 (72/73) was confirmed, and sequences of DNA-PK catalytic subunit (DNA-PKcs), HA95, Hsp27, prolyl 4-hydroxylase ?-1 subunit, ?-tubulin, and ?-tubulin were identified. The fraction of total cellular HA95 that associated with FLP was very high, while progressively lower fractions of the total DNA-PKcs, Hsp70, Hsp 27, ?-tubulin, and ?-tubulin specifically associated with EBNA-LP as determined by immunoblotting with antibodies to these proteins. EBNA-LP bound to two domains in the DNA-PKcs C terminus and DNA-PKcs associated with the EBNA-LP repeat domain. DNA-PKcs that was bound to EBNA-LP phosphorylated p53 or EBNA-LP in vitro, and the phosphorylation of EBNA-LP was inhibited by Wortmannin, a specific in vitro inhibitor of DNA-PKcs. PMID:11160753

Han, Innoc; Harada, Shizuko; Weaver, David; Xue, Yong; Lane, William; Orstavik, Sigurd; Skalhegg, Bjorn; Kieff, Elliott

2001-01-01

266

Multi-objective fuzzy-GA formulation for optimal placement and sizing of shunt FACTS controller  

Microsoft Academic Search

The location and sizing of FACTS controllers for voltage stability enhancement is an important consideration for practical power systems. In this paper, a strategy for placement and sizing of shunt FACTS controller using Fuzzy logic and Real Coded Genetic Algorithm is proposed. A fuzzy performance index based on distance to saddle-node bifurcation, voltage profile and capacity of shunt FACTS controller

A. R. Phadke; Manoj Fozdar; K. R. Niazi

2009-01-01

267

Electromagnetic Shunt Damping S. Behrens A. J. Fleming S. O. Reza Moheimani  

E-print Network

Electromagnetic Shunt Damping S. Behrens A. J. Fleming S. O. Reza Moheimani School of Electricalqhzfdvwoh1hgx1dx Abstract A method for electromagnetic shunt damping (EMSD) will be presented in this paper. A passive control strategy is validated through experi- mentation on a simple electromagnetic mass

Fleming, Andrew J.

268

Uniform model for series RL and parallel RL shunt circuits and power consumption  

Microsoft Academic Search

A simple impedance based analysis is presented for resonant shunt circuits. The formulation is compatible with arrangement of shunt electronics and is used to clarify previously published resonance condition and to examine power. Since our resonance condition is contrary to previously published results, experimental verification is also presented. The experiments consist of both a series and parallel second mode absorber

Chul H. Park; Daniel J. Inman

1999-01-01

269

Normal-pressure hydrocephalus: current understanding of diagnostic tests and shunting  

SciTech Connect

Normal-pressure hydrocephalus is no longer difficult to diagnose or treat-cranial computed tomographic scanning has made the diagnosis of ventricular enlargement straightforward, and shunt placement often helps the patient whose condition can be traced to a specific cause. Predicting accurately whether a patient will benefit from a shunt, however, is still problematic.

Black, P.M.

1982-02-01

270

Finite element-based analysis of shunted piezoelectric structures for vibration damping  

Microsoft Academic Search

Piezoelectric patches shunted with passive electrical networks can be attached to a host structure for reduction of structural vibrations. This approach is frequently called “shunted piezo damping” and has the advantage of guaranteed stability and low complexity in implementation. For numerical treatment of such structures, a finite element modelling methodology is presented that incorporates both the piezoelectric coupling effects of

Jens Becker; Oliver Fein; Matthias Maess; Lothar Gaul

2006-01-01

271

Evaluation of MR/Fluoroscopyguided Portosystemic Shunt Creation in a Swine Model  

E-print Network

and the bridging stent had more secure anchoring mechanisms but also had higher technical failure rates (50% and 40 DESPITE advances in medical and surgical therapies, the management of portal hypertension remains a chal- renal shunt to decompress the splenic vein (3,4). Because the creation of these shunts is selective

Atalar, Ergin

272

Shunt capacitor sizing for radial distribution feeders with distorted substation voltages  

Microsoft Academic Search

It is well known that a major portion of power system losses occur at the distribution level. Some of these losses can be eliminated by proper selection of shunt capacitors on primary feeders via power factor correction. The objective of this paper is to present an algorithm for optimizing shunt capacitor sizes on radial distribution lines with nonsinusoidal substation voltages,

Y. Baghzouz; S. Ertem

1990-01-01

273

Reasons, procedures, and outcomes in ventriculoatrial shunts: A single-center experience  

PubMed Central

Background: Ventricular shunts are used to drain cerebrospinal fluid into extra-cranial spaces. Ventriculoatrial (VA) shunts are provided to transfer cerebrospinal fluid from the cerebral ventricle into the right atrium of the heart. A single center experience of indications, procedure, and clinical outcomes in VA shunt was presented in current study. Methods: VA shunts were applied in 10 patients who had repeated previous shunt dysfunction or infection. The reasons, clinical findings, replacement methods, and postoperative clinical follow-ups and outcomes were recorded retrospectively. Results: There were seven female (70%) and three (30%) male patients; their ages ranged from 5 to 13 years (mean ± SD; 8.5 ± 2.6 years). Shunt re-placement reasons were as follows: Shunt occlusion in five patients, intraperitoneal infection in four patients and a distal catheter was kinked and knotted in one patient. Postoperative early complications were seen in one patient as early catheter thrombosis and catheter revision were applied. Late complications were seen in two patients as follows: Catheter infection and infective endocarditis occurred in one patient and pulmonary thrombus occurred in one other patient. There was not any catheter-related mortality observed at the one year follow-up period. Conclusion: VA shunts may be an option for cerebrospinal fluid drainage at necessary conditions. However, sterilization and general training on asepsy and antisepsy are the most important determinants affecting the clinical outcome due to the cardio systemic relationship. PMID:23493480

Yavuz, Celal; Dem?rtas, Sinan; Cal?skan, Ahmet; Kamasak, Kaan; Karahan, Oguz; Guclu, Orkut; Yaz?c?, Suleyman; Mav?tas, Binali

2013-01-01

274

49 CFR 236.309 - Loss of shunt protection; where required.  

Code of Federal Regulations, 2014 CFR

...SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Interlocking Standards § 236.309 Loss of shunt protection; where...permit an established route to be changed at an automatic interlocking. (b) A loss of shunt of 5 seconds or less shall...

2014-10-01

275

49 CFR 236.309 - Loss of shunt protection; where required.  

Code of Federal Regulations, 2010 CFR

...SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Interlocking Standards § 236.309 Loss of shunt protection; where...permit an established route to be changed at an automatic interlocking. (b) A loss of shunt of 5 seconds or less shall...

2010-10-01

276

49 CFR 236.309 - Loss of shunt protection; where required.  

Code of Federal Regulations, 2013 CFR

...SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Interlocking Standards § 236.309 Loss of shunt protection; where...permit an established route to be changed at an automatic interlocking. (b) A loss of shunt of 5 seconds or less shall...

2013-10-01

277

49 CFR 236.309 - Loss of shunt protection; where required.  

Code of Federal Regulations, 2011 CFR

...SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Interlocking Standards § 236.309 Loss of shunt protection; where...permit an established route to be changed at an automatic interlocking. (b) A loss of shunt of 5 seconds or less shall...

2011-10-01

278

49 CFR 236.309 - Loss of shunt protection; where required.  

Code of Federal Regulations, 2012 CFR

...SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Interlocking Standards § 236.309 Loss of shunt protection; where...permit an established route to be changed at an automatic interlocking. (b) A loss of shunt of 5 seconds or less shall...

2012-10-01

279

Results of Treatment with Ventriculoatrial and Ventriculoperitoneal Shunt in Infantile Nontumoral Hydrocephalus  

Microsoft Academic Search

The authors present the results of surgical treatment in 165 children with nontumoral hydrocephalus, treated during a period of 11 years. The minimum period of follow-up was 1 year. The results in the group of children treated with a ventriculoatrial (VA) shunt were compared to those obtained in the group with a ventriculoperitoneal (VP) shunt. 45% of patients with VA

Carlo Mazza; Alberto Pasqualin; Renato Da Pian; Anthony J. Raimondi

1980-01-01

280

Management of cardiac migration of a distal shunt catheter: The radiological pitfalls.  

PubMed

Cardiac migration is a rare complication of the ventriculoperitoneal shunt. We report a case of a late migration of the distal shunt into the pulmonary arteries. The authors underline the radiological features that suggested the presence of a knot. Preoperative planning and the assistance of a vascular surgeon were required due to the presence of a knot. PMID:25583350

Aboukais, R; Zairi, F; Marinho, P; Lejeune, J-P

2015-02-01

281

A modification of Winter's shunt in the treatment of pediatric low-flow priapism  

Microsoft Academic Search

PurposeCavernous shunt operations available for treating priapism are frequently unsuitable for children owing to high chances of persistent venous leak that results in postoperative erectile dysfunction. In this article, a modification of Winter's shunt, which is suitable for treating low-flow priapism in children, is described.

Venkatachalam Raveenthiran

2008-01-01

282

Subdural hemorrhage of the cauda equina. A rare complication of cerebrospinal fluid shunt. Case report  

Microsoft Academic Search

We describe the case of a 16-year-old boy with idiopathic hydrocephalus, who developed cranial subdural hygromas and subsequent cranial subdural hemorrhage after a shunting procedure. Sciatica and radicular lumbar pain initially seemed to be unrelated to the preceeding implantation of a ventriculoatrial shunt. CT scan revealed a sharply demarcated hyperdensity in the lumbar subdural space with compression of the cauda

Gabriele Wurm; Peter Pogady; Karin Lungenschmid; Johannes Fischer

1996-01-01

283

How shunting inhibition affects the discharge of lumbar motoneurones. A dynamic clamp study in anaesthetised cats  

E-print Network

motoneurones with a microelectrode. The reversal potential of this current could be set at the resting potential so as to prevent membrane depolarisation or hyperpolarisation. The only effect of the dynamic called the shunt potential. The shunt potential ranged between 11 and 37 mV above the resting potential

van Vreeswijk, Carl

284

Prevention of Arteriovenous Shunt Occlusion Using Microbubble and Ultrasound Mediated Thromboprophylaxis  

PubMed Central

Background Palliative shunts in congenital heart disease patients are vulnerable to thrombotic occlusion. High mechanical index (MI) impulses from a modified diagnostic ultrasound (US) transducer during a systemic microbubble (MB) infusion have been used to dissolve intravascular thrombi without anticoagulation, and we sought to determine whether this technique could be used prophylactically to reduce thrombus burden and prevent occlusion of surgically placed extracardiac shunts. Methods and Results Heparin?bonded ePTFE tubular vascular shunts of 4 mm×2.5 cm (Propaten; W.L Gore) were surgically placed in 18 pigs: a right?sided side?to?side arteriovenous (AV, carotid?jugular) shunt, and a left?sided arterio?arterial (AA, carotid?carotid) interposition shunt in each animal. After shunt implantation, animals were randomly assigned to one of 3 groups. Transcutaneous, weekly 30?minute treatments (total of 4 treatments) of either guided high MI US+MB (Group 1; n=6) using a 3% MRX?801 MB infusion, or US alone (Group 2; n=6) were given separately to each shunt. The third group of 6 pigs received no treatments. The shunts were explanted after 4 weeks and analyzed by histopathology to quantify luminal thrombus area (mm2) for the length of each shunt. No pigs received antiplatelet agents or anticoagulants during the treatment period. The median overall thrombus burden in the 3 groups for AV shunts was 5.10 mm2 compared with 4.05 mm2 in AA (P=0.199). Group 1 pigs had significantly less thrombus burden in the AV shunts (median 2.5 mm2) compared with Group 2 (median 5.6 mm2) and Group 3 (median 7.5 mm2) pigs (P=0.006). No difference in thrombus burden was seen between groups for AA shunts. Conclusion Transcutaneous US with intravenous MB is capable of preventing thrombus accumulation in arteriovenous shunts without the need for antiplatelet agents, and may be a method of preventing progressive occlusion of palliative shunts. PMID:24518555

Kutty, Shelby; Wu, Juefei; Hammel, James M.; Abraham, Joseph R.; Venkataraman, Jeeva; Abdullah, Ibrahim; Danford, David A.; Radio, Stanley J.; Lof, John; Porter, Thomas R.

2014-01-01

285

Sound absorption of a finite micro-perforated panel backed by a shunted loudspeaker.  

PubMed

Deep back cavities are usually required for micro-perforated panel (MPP) constructions to achieve good low frequency absorption. To overcome the problem, a close-box loudspeaker with a shunted circuit is proposed to substitute the back wall of the cavity of the MPP constructions to constitute a composite absorber. Based on the equivalent circuit model, the acoustic impedance of the shunted loudspeaker is formulated first, then a prediction model of the sound absorption of the MPP backed by shunted loudspeaker is developed by employing the mode solution of a finite size MPP coupled by an air cavity with an impendence back wall. The MPP absorbs mid to high frequency sound, and with properly adjusted electrical parameters of its shunted circuit, the shunted loudspeaker absorbs low frequency sound, so the composite absorber provides a compact solution to broadband sound control. Numerical simulations and experiments are carried out to validate the model. PMID:24437763

Tao, Jiancheng; Jing, Ruixiang; Qiu, Xiaojun

2014-01-01

286

Tunable band gaps in acoustic metamaterials with periodic arrays of resonant shunted piezos  

NASA Astrophysics Data System (ADS)

Periodic arrays of resonant shunted piezoelectric patches are employed to control the wave propagation in a two-dimensional (2D) acoustic metamaterial. The performance is characterized by the finite element method. More importantly, we propose an approach to solving the conventional issue of the nonlinear eigenvalue problem, and give a convenient solution to the dispersion properties of 2D metamaterials with periodic arrays of resonant shunts in this article. Based on this modeling method, the dispersion relations of a 2D metamaterial with periodic arrays of resonant shunted piezos are calculated. The results show that the internal resonances of the shunting system split the dispersion curves, thereby forming a locally resonant band gap. However, unlike the conventional locally resonant gap, the vibrations in this locally resonant gap are unable to be completely localized in oscillators consisting of shunting inductors and piezo-patches.

Chen, Sheng-Bing; Wen, Ji-Hong; Wang, Gang; Wen, Xi-Sen

2013-07-01

287

Stent angioplasty of narrowed portocaval shunt in Budd Chiari syndrome: a case report  

PubMed Central

Background Hepatic vein thrombosis (Budd-Chiari Syndrome) is a rare disorder resulting from an obstruction to the outflow of blood from the liver. Early decompression is needed to prevent liver dysfunction and death. Radiological intervention includes angioplasty of stenosis and webs and the placement of transjugular intrahepatic portosystemic shunts (TIPPS). Side-to-side portacaval shunt (SSPCS) remains the gold standard for achieving good long-term results. Case presentation A 37-year old lady underwent side-to-side portacaval shunt for Budd Chiari syndrome. She had early shunt blockage and this was successfully treated with the placement of a metallic stent across the shunt. Conclusion At five years, she remains asymptomatic, with normal liver functions, no ascites, and normal flow through the stent on Colour Doppler examination. PMID:19117529

2009-01-01

288

Vibration control of an HDD disk-spindle system utilizing piezoelectric bimorph shunt damping: I. Dynamic analysis and modeling of the shunted drive  

NASA Astrophysics Data System (ADS)

This work proposes a new piezoelectric shunt damping methodology to control the vibration of a computer hard disk drive (HDD) disk-spindle system. The first part of this work (part I) deals with dynamic modeling of the piezoelectric shunted drive, while the second part of this work (part II) covers experimental implementation of the proposed shunt circuits. In the modeling, a target vibration mode which significantly restricts the recording density increment of the drive is determined by analyzing the dynamic characteristics of the conventional drive. This is achieved by undertaking both modal testing and finite element (FE) analysis. In order to effectively suppress the unwanted vibration of the target mode, a piezoelectric bimorph is then designed and integrated to the drive by considering the mode shapes of the target vibration mode. The mechanical impedance of the shunted bimorph is derived from lamination theory and piezoelectric constitutive equations. In this derivation, the electromechanical coupling coefficient of the shunted drive is analytically incorporated with the mechanical impedance. Using the coupling coefficient, the shunt damping performance for the target vibration mode is predicted and evaluated by presenting the displacement transmissibility.

Lim, S. C.; Choi, S. B.

2007-06-01

289

Improved piezoelectric switch shunt damping technique using negative capacitance  

NASA Astrophysics Data System (ADS)

This paper proposes an adaptive shunt damping circuit for improved damping performance. It consists of a switched inductance-resistance network (SSDI), which is connected in parallel to a negative capacitance. This circuit is in the following called 'synchronized switching damping on negative capacitor and inductor' (SSDNCI). It combines the adaptive nature of the SSDI technique and the improved performance of a negative capacitance. By the action of the switch device, the piezoelectric element is periodically held under both states of the nonlinear shunt and therefore adapts to the frequency of excitation. The analysis in this publication is performed based on the typical assumptions of a single degree-of-freedom oscillator. The stationary charge signal and energy dissipation are derived as functions of the ratio between the negative capacitance and piezoelectric capacitance. Calculation results show that the dissipated energy grows with the negative capacitance up to the stability boundary of the system. Measurements are conducted on a clamped beam test rig to validate the theoretical results. In the operative range of the negative capacitance which is used in this research, an increase in nearly 220% in energy dissipation compared to the standard SSDI technique is achieved.

Han, Xu; Neubauer, Marcus; Wallaschek, Jörg

2013-01-01

290

Transjugular Intrahepatic Portosystemic Shunts in Children with Biliary Atresia  

SciTech Connect

Purpose: We retrospectively evaluated the technical and long-term clinical results of transjugularintrahepatic portosystemic shunts (TIPS) in children with portal hypertension and biliary atresia (BA). Methods: Nine children with BA and recurrent bleeding from esophagogastric and/or intestinal varices were treated by TIPS at the age of 34-156 months and followed-up in two centers. Different types of stents were used. Results: Shunt insertion succeeded in all patients, but in two a second procedure was necessary. Seven procedures lasted more than 3 hr, mainly due to difficult portal vein puncture.Variceal bleeding ceased in all patients; however, 16 reinterventions were performed in eight patients for clinical reasons (n =11) and sonographically suspected restenosis (n =5). Four patients underwent successful liver transplantation 4-51 months after TIPS and five are in good clinical conditions 64-75 months after TIPS. Conclusions: TIPS in children with BA is technically difficult, mainly due to periportal fibrosis and small portal veins. Frequency of reinterventions seems to be higher compared with adults.

Huppert, Peter E. [Department of Diagnostic Radiology, Eberhard Karls University of Tuebingen, Hoppe-Seyler-Strasse 3, D-72076 Tuebingen (Germany); Goffette, Pierre [Department of Vascular and Interventional Radiology, St. Luc University Hospital of Brussels, Av. Hippocrate 10 UCL 10/29.42, Brussels (Belgium); Astfalk, Wolfgang [Department ofPediatric Surgery, Eberhard Karls University of Tuebingen, Hoppe-Seyler Strasse 3, D-72076 Tuebingen (Germany); Sokal, Emil M. [Department ofPediatrics, St. Luc University Hospital of Brussels, Av. Hippocrate 10 UCL 10/29.42, Brussels (Belgium); Brambs, Hans-Juergen; Schott, Ullrich; Duda, Stephan H. [Department of Diagnostic Radiology, Eberhard Karls University of Tuebingen, Hoppe-Seyler-Strasse 3, D-72076 Tuebingen (Germany); Schweizer, Paul [Department of Pediatric Surgery, Eberhard Karls University of Tuebingen, Hoppe-Seyler Strasse 3, D-72076 Tuebingen (Germany); Claussen, Claus D. [Department of Diagnostic Radiology, Eberhard Karls University of Tuebingen, Hoppe-Seyler-Strasse 3, D-72076 Tuebingen (Germany)

2002-12-15

291

Hepatic focal nodular hyperplasia with congenital portosystemic shunt.  

PubMed

Hepatic focal nodular hyperplasia (FNH) is a rare benign tumor in children. Vascular anomalies have been identified as pathological features of FNH, but the etiology remains unclear. We describe a rare case including the time course of formation of hepatic FNH in response to congenital portosystemic shunt (PSS). A 4-month-old girl was identified on newborn mass screening to have hypergalactosemia, but no inherited deficiencies in galactose-metabolizing enzymes were found. Ultrasonography and per-rectal portal scintigraphy showed intrahepatic PSS of the right lobe as a cause of the hypergalactosemia. At age 12 months, the patient had elevated hepatic enzymes and small hypoechoic hepatic lesions around the shunt. On abdominal contrast-enhanced ultrasonography spoke-wheel sign and central stellate scar were seen, which are typical features of hepatic FNH without biopsy. Congenital intrahepatic PSS should be evaluated on abdominal contrast-enhanced ultrasonography and observed over time because of its potential to develop into hepatic FNH. PMID:25521987

Cho, Yuki; Shimono, Taro; Morikawa, Hiroyasu; Shintaku, Haruo; Tokuhara, Daisuke

2014-12-01

292

Left ventricular to right atrial shunt (Gerbode defect): congenital versus acquired  

PubMed Central

Introduction Congenital left ventricular to right atrial (LV-RA) shunt (Gerbode defect) is rare, while acquired LV-RA shunt has been increasingly reported. As yet, systematically incorporated data of the LV-RA shunt have not been presented. Aim To present the clinical features, diagnostic challenge and management strategies of congenital and acquired LV-RA shunts. Material and methods The data source was based on a comprehensive literature retrieval of the LV-RA shunt in the period 1990–2013. Results In comparison with the acquired Gerbode defect, the congenital Gerbode defect group of patients were younger and were associated more often with additional congenital disorders. Previous cardiac surgery and infective endocarditis were the two major aetiologies of the occurrence of the acquired shunts. Paravalvular abscess was associated in 10.2% and atrioventricular block in 13.6% of the acquired group patients. Transoesophageal echocardiography showed a higher diagnostic accuracy, lower missed diagnosis and lower inclusive diagnosis rates, in comparison to transthoracic echocardiography, but the misdiagnosis rates of the two modalities did not differ from each other. Four (4.5%) of the acquired group patients were complicated by atrioventricular block following surgical or interventional closure of the shunt. Eight (9.1%) patients died in the acquired group, but no patient died in the congenital group. Conclusions The diagnosis of an LV-RA shunt is quite challenging, especially in the context of coexisting abnormalities including an additional intracardiac shunt, tricuspid regurgitation, pulmonary artery hypertension and infective endocarditis, which have to be carefully differentiated from the shunt by further investigations. A better control of infective complications and careful manoeuvres during surgery may help to keep the LV-RA-sensitive septum intact. PMID:25489305

2014-01-01

293

Decreased Electroporation Efficiency in Borrelia burgdorferi Containing Linear Plasmids lp25 and lp56: Impact on Transformation of Infectious B. burgdorferi  

Microsoft Academic Search

The presence of the linear plasmids lp25 and lp56 of Borrelia burgdorferi B31 was found to dramatically decrease the rate of transformation by electroporation with the shuttle vector pBSV2, an autonomously replicating plasmid that confers kanamycin resistance (P. E. Stewart, R. Thalken, J. L. Bono, and P. Rosa, Mol. Microbiol. 39:714-721, 2001). B. burgdorferi B31 clones had transformation efficiencies that

Matthew B. Lawrenz; Hiroki Kawabata; Joye E. Purser; Steven J. Norris

2002-01-01

294

Automated Test Assembly Using lp_Solve Version 5.5 in R  

ERIC Educational Resources Information Center

This article reviews the use of the software program lp_solve version 5.5 for solving mixed-integer automated test assembly (ATA) problems. The program is freely available under Lesser General Public License 2 (LGPL2). It can be called from the statistical language R using the lpSolveAPI interface. Three empirical problems are presented to…

Diao, Qi; van der Linden, Wim J.

2011-01-01

295

An LP decoding algorithm based on primal path-following interior point method  

Microsoft Academic Search

The paper presents an implementation of LP decoding algorithm based on the primal path-following interior point method. Numerical examples show some behaviors of an LP decoder based on the exact interior point method. It is shown that very accurate solution can be obtained after 40-50 iterations of the outer loop of the interior point method. Complexity analysis on the proposed

Tadashi Wadayama

2009-01-01

296

75 FR 74029 - Sabine Pass LNG, L.P.; Notice of Application  

Federal Register 2010, 2011, 2012, 2013, 2014

...Docket No. CP11-32-000] Sabine Pass LNG, L.P.; Notice of Application November...that on November 12, 2010, Sabine Pass LNG, L.P. (Sabine Pass), 700 Milam Street...gas compressor at its existing Sabine Pass LNG Terminal, located in Cameron Parish,...

2010-11-30

297

76 FR 40723 - Dominion Cove Point LNG, LP; Notice of Technical Conference  

Federal Register 2010, 2011, 2012, 2013, 2014

...RP11-2136-000; RP11-2137-000] Dominion Cove Point LNG, LP; Notice of Technical Conference On May 27, 2011, pursuant...section 4 of the Natural Gas Act (NGA), Dominion Cove Point LNG, LP (Cove Point) filed revised tariff records in Docket...

2011-07-11

298

77 FR 28375 - Eagle Rock Desoto Pipeline, L.P.; Notice of Petition for Rate Approval  

Federal Register 2010, 2011, 2012, 2013, 2014

...Federal Energy Regulatory Commission [Docket No. PR12-25-000] Eagle Rock Desoto Pipeline, L.P.; Notice of Petition for Rate Approval Take notice that on May 1, 2012, Eagle Rock Desoto Pipeline, L.P. (Desoto) filed a Rate...

2012-05-14

299

76 FR 20971 - Eagle Rock Desoto Pipeline, L.P.; Notice of Filing  

Federal Register 2010, 2011, 2012, 2013, 2014

...ENERGY Federal Energy Regulatory Commission [Docket No. PR10-120-001] Eagle Rock Desoto Pipeline, L.P.; Notice of Filing Take notice that on April 7, 2011, Eagle Rock Desoto Pipeline, L.P. filed a revised Statement of Operating...

2011-04-14

300

75 FR 27774 - Eagle Rock Desoto Pipeline, L.P.; Notice of Rate Election  

Federal Register 2010, 2011, 2012, 2013, 2014

...Federal Energy Regulatory Commission [Docket No. PR10-22-000] Eagle Rock Desoto Pipeline, L.P.; Notice of Rate Election May 11, 2010. Take notice that on May 3, 2010, Eagle Rock Desoto Pipeline, L.P., (Desoto) filed a Notice...

2010-05-18

301

76 FR 4648 - PowerSmith Cogeneration Project, LP; Notice of Filing  

Federal Register 2010, 2011, 2012, 2013, 2014

...EL11-15-000; QF86-36-005] PowerSmith Cogeneration Project, LP; Notice of Filing January...that on January 13, 2011, PowerSmith Cogeneration Project, LP (PowerSmith), pursuant...Regulations for the topping-cycle cogeneration facility owned and operated by...

2011-01-26

302

77 FR 13593 - PowerSmith Cogeneration Project, LP; Notice of Request for Waiver  

Federal Register 2010, 2011, 2012, 2013, 2014

...EL12-37-000; QF86-36-006] PowerSmith Cogeneration Project, LP; Notice of Request for...18 CFR 292.205(c), PowerSmith Cogeneration Project, LP (PowerSmith) filed a...Regulations for the topping- cycle cogeneration facility owned and operated by...

2012-03-07

303

77 FR 71585 - Brookfield Energy Marketing LP v. ISO New England Inc.; Notice of Complaint  

Federal Register 2010, 2011, 2012, 2013, 2014

...EL13-23-000] Brookfield Energy Marketing LP v. ISO New England Inc.; Notice...e) and 825(e), Brookfield Energy Marketing LP (Complainant) filed a formal complaint...DC 20426. This filing is accessible on-line at http://www.ferc.gov,...

2012-12-03

304

15 Aug 2003 Diffraction and Vector Meson Production, LP03 1 Diffraction and Vector  

E-print Network

15 Aug 2003 Diffraction and Vector Meson Production, LP03 1 Diffraction and Vector Meson Production and Photon Interactions at High Energies #12;Diffraction and Vector Meson Production, LP03 215 Aug 2003 Diffractive processes t-channel exchange of the vacuum quantum numbers Colourless exchange Small momentum

305

A study of tighter lower bounds in LP relaxation based placement  

Microsoft Academic Search

Placement strategies for cell-based designs which use a linear programming (LP) relaxation are widely believed to have certain weaknesses. Among these is the phenomenon that the relaxed placement produced by the LP-solver often has excessive cell overlap; this makes the relaxed solution quite distant from a legal one and raises questions about the value of the relaxed solution. An implication

Devang Jariwala; John Lillis

2005-01-01

306

An LP-based methodology for improved timing-driven placement  

Microsoft Academic Search

A method for timing driven placement is presented. The core of the approach is optimal timing-driven relaxed place- ment based on a linear programming (LP) formulation. The formulation captures all topological paths in a linear sized LP and thus, heuristic net weights or net budgets are not necessary. Additionally, explicit enumeration of a large number of paths is avoided. The

John Lillis; Shubhankar Sanyal

2005-01-01

307

75 FR 35017 - Brookfield Energy Marketing LP; Supplemental Notice That Initial Market-Based Rate Filing...  

Federal Register 2010, 2011, 2012, 2013, 2014

...ER10-1427-000] Brookfield Energy Marketing LP; Supplemental Notice That...proceeding of Brookfield Energy Marketing LP's application for market-based...lieu of paper, using the FERC Online links at http://www.ferc...For assistance with any FERC Online service, please e-mail...

2010-06-21

308

29 CFR 1926.153 - Liquefied petroleum gas (LP-Gas).  

Code of Federal Regulations, 2010 CFR

...directed toward any LP-Gas container within 20 feet...located in an unpartitioned area on the same floor, the...tank. (n) When LP-Gas and one or more other gases are stored or used in the same area, the containers shall...

2010-07-01

309

76 FR 66618 - Airworthiness Directives; Eurocopter France (Eurocopter) Model EC225LP Helicopters  

Federal Register 2010, 2011, 2012, 2013, 2014

...Eurocopter Model EC225LP helicopters. This AD requires...discovery of two fatigue cracks in the dome...causing damage to the helicopter and injury to people...Eurocopter Model EC225LP helicopters. EASA advises that two fatigue cracks were...

2011-10-27

310

Immunological crossreactivity between Lp(a) and the third component of complement  

SciTech Connect

Lipoprotein(a) (Lp(a)) is known to be an independent risk factor for atherosclerosis, yet little is known about its physiological role. During the authors investigation of the site of synthesis of Lp(a), they made the observation that the third component of complement (C3) reacts with antisera to Lp(a). Hep G-2 cells or rhesus liver organ cultures were labelled using TVS-methionine in serum-free, methionine-free DMEM. The labelled media were immunoprecipitated with antisera raised in the goat and the rabbit against Lp(a) and apolipoprotein(a) (apo(a)). The immunoprecipitates were subjected to electrophoresis on 2.5 - 16% gradient gels and visualized by autoradiography. All antisera consistently precipitated a significant amount of C3. This reaction with C3 could be inhibited by competition with pure preparations of Lp(a) and apo(a) or by preincubation of the medium with antiserum to C3. In addition, immunoprecipitation of C3 by anti-C3 was inhibited by competition with both apo(a) and Lp(a). No cross-reactivity was observed with antisera to apoB, apoE, normal rabbit serum, or purified non-specific rabbit IgG. This unexpected crossreactivity between Lp(a) and C3, observed in vitro, may have biological relevance and suggests a possible relationship between Lp(a) and the immune system.

Fless, G.M.; ZumMallen, M.E.

1987-05-01

311

10LP models for agricultural policy analysis: with implications for resource conservation and development program planning  

Microsoft Academic Search

A 38 sector Input-Output (10) model is linked with an agricultural linear Programming (LP) model to illustrate the effectiveness of combining 10-LP techniques in analyzing economic effects of natural resource projects and development alternatives. The model is applied to resource use and economic expansion questions to illustrate its usefulness in regional development planning. Model applications included estimating the impact of

C. D. Jr. Jones; W. Y. Huang

1983-01-01

312

75 FR 19643 - West Oaks Energy LP; Supplemental Notice That Initial Market-Based Rate Filing Includes Request...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Regulatory Commission [Docket No. ER10-1029-000] West Oaks Energy LP; Supplemental Notice That Initial Market- Based Rate...supplemental notice in the above-referenced proceeding of West Oaks Energy LP's application for market-based rate...

2010-04-15

313

77 FR 33716 - Foreign-Trade Zone 70-Detroit, MI; Expansion of Subzone; Marathon Petroleum Company LP, (Oil...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Foreign-Trade Zone 70--Detroit, MI; Expansion of Subzone; Marathon Petroleum Company LP, (Oil Refinery) Detroit, MI An application...70, requesting an expansion of Subzone 70T, on behalf of Marathon Petroleum Company LP in Detroit, Michigan. The...

2012-06-07

314

78 FR 18329 - Gulf South Pipeline Company, LP; Petal Gas Storage, L.L.C.; Notice of Application  

Federal Register 2010, 2011, 2012, 2013, 2014

...Pipeline Company, LP (Gulf South), 9 Greenway Plaza, Suite 2800, Houston, Texas...Gas Storage, L.L.C. (Petal), 9 Greenway Plaza, Suite 2800, Houston, Texas...Boardwalk Pipeline Partners, LP, 9 Greenway Plaza, Houston, Texas 77046, by...

2013-03-26

315

Skin hydration and possible shunt route penetration in controlled estradiol delivery from ultradeformable and standard liposomes.  

PubMed

Human skin delivery of estradiol from ultradeformable and traditional liposomes was explored, comparing occlusive and open application, with the aim of examining the role of skin hydration. Partially hydrated epidermis was used for open hydration, but fully hydrated membranes were used for occluded studies. In addition, we developed a novel technique to investigate the role of shunt route penetration in skin delivery of liposomal estradiol. This compared delivery through epidermis with that through a stratum corneum (SC)/epidermis sandwich from the same skin with the additional SC forming the top layer of the sandwich. This design was based on the fact that orifices of shunts only occupy 0.1% of skin surface area and thus for SC/epidermis sandwiches there will be a negligible chance for shunts to superimpose. The top SC thus blocks most shunts available on the bottom membrane. If shunts play a major role then the delivery through sandwiches should be much reduced compared with that through epidermis, taking into consideration the expected reduction owing to increased membrane thickness. After open application, both ultradeformable and traditional liposomes improved estradiol skin delivery, with the ultradeformable liposomes being superior. Occlusion reduced the delivering efficiency of both vesicle types, supporting the theory that a hydration gradient provides the driving force. Shunt route penetration was found to play only a very minor role in liposomal delivery. In conclusion, full hydration of skin reduces estradiol delivery from liposomes and the shunt route is not the main pathway for this delivery. PMID:11697538

El Maghraby, G M; Williams, A C; Barry, B W

2001-10-01

316

Flexural wave band-gaps in phononic metamaterial beam with hybrid shunting circuits  

NASA Astrophysics Data System (ADS)

Periodic arrays of hybrid-shunted piezoelectric patches are used to control the band-gaps of phononic metamaterial beams. Passive resistive-inductive (RL) shunting circuits can produce a narrow resonant band-gap (RG), and active negative capacitive (NC) shunting circuits can broaden the Bragg band-gaps (BGs). In this article, active NC shunting circuits and passive resonant RL shunting circuits are connected to the same piezoelectric patches in parallel, which are usually called hybrid shunting circuits, to control the location and the extent of the band-gaps. A super-wide coupled band-gap is generated when the coupling between RG and the BG occurs. The attenuation constant of the infinite periodic structure is predicted by the transfer matrix method, which is compared with the vibration transmittance of a finite periodic structure calculated by the finite element method. Numerical results show that the hybrid-shunting circuits can make the band-gaps wider by appropriately selecting the inductances, negative capacitances, and resistances. Project supported by the National Natural Science Foundation of China (Grant Nos. 51275519 and 51175501).

Zhang, Hao; Wen, Ji-Hong; Chen, Sheng-Bing; Wang, Gang; Wen, Xi-Sen

2015-03-01

317

Correlation of experimental rCBF determinations in goats with flow measurements from a Doppler-modified carotid artery shunt  

SciTech Connect

A carotid artery shunt system has been developed that continuously monitors blood flow rates by embedding a Doppler crystal in the shunt wall. The crystal ranges through a liquid lens that enables it to be placed without violation of the shunt lumen. Because the crystal is at a fixed angle (45 degrees) to the axis of blood flow and the diameter of the lumen remains constant, a linear relationship exists between flow rates and the Doppler velocity signal. This shunt system was previously tested in vitro using a pulsatile pump and was found to be accurate to within 4.7% of the actual flow rate. In the present study, animal (goat) experiments were performed consisting of simultaneous carotid shunt flow and bilateral rCBF measurements by the radiolabeled microsphere technique to determine in vivo the accuracy of this Doppler modified shunt and to ascertain the ability of shunt flow to increase in the face of acute contralateral carotid occlusion. Data from five animals show that in vivo shunt flow can be recorded to within 13% of control rCBF and that shunt flow increases nearly 50% under conditions of distal demand (contralateral carotid occlusion). This device may prove useful in laboratory studies of carotid shunt dynamics and in clinical practice to quickly detect correctable shunt flow abnormalities.

Loftus, C.M.; Silvidi, J.A.; Becker, J.A.; Miller, B.V.; Bernstein, D.D.

1989-01-01

318

Staged Transcatheter Treatment of Portal Hypoplasia and Congenital Portosystemic Shunts in Children  

SciTech Connect

Purpose: Congenital portosystemic shunts (CPSS) with portal venous hypoplasia cause hyperammonemia. Acute shunt closure results in portal hypertension. A transcatheter method of staged shunt reduction to afford growth of portal vessels followed by shunt closure is reported. Methods: Pressure measurements and angiography in the CPSS or superior mesenteric artery (SMA) during temporary occlusion of the shunt were performed. If vessels were diminutive and the pressure was above 18 mmHg, a staged approach was performed, which included implantation of a tailored reducing stent to reduce shunt diameter by {approx}50 %. Recatheterization was performed approximately 3 months later. If the portal pressure was below 18 mmHg and vessels had developed, the shunt was closed with a device. Results: Six patients (5 boys, 1 girl) with a median age of 3.3 (range 0.5-13) years had CPSS portal venous hypoplasia and hyperammonemia. Five patients underwent staged closure. One patient tolerated acute closure. One patient required surgical shunt banding because a reducing stent could not be positioned. At median follow-up of 3.8 (range 2.2-8.4) years, a total of 21 procedures (20 transcatheter, 1 surgical) were performed. In all patients, the shunt was closed with a significant reduction in portal pressure (27.7 {+-} 11.3 to 10.8 {+-} 1.8 mmHg; p = 0.016), significant growth of the portal vessels (0.8 {+-} 0.5 to 4.0 {+-} 2.4 mm; p = 0.037), and normalization of ammonia levels (202.1 {+-} 53.6 to 65.7 {+-} 9.6 {mu}mol/L; p = 0.002) with no complications. Conclusion: Staged CPSS closure is effective in causing portal vessel growth and treating hyperammonemia.

Bruckheimer, Elchanan, E-mail: elchananb@bezeqint.net; Dagan, Tamir [Schneider Children's Medical Center Israel, Section of Pediatric Cardiology (Israel)] [Schneider Children's Medical Center Israel, Section of Pediatric Cardiology (Israel); Atar, Eli; Schwartz, Michael [Schneider Children's Medical Center Israel, Section of Radiology (Israel)] [Schneider Children's Medical Center Israel, Section of Radiology (Israel); Kachko, Ludmila [Schneider Children's Medical Center Israel, Section of Anesthesiology (Israel)] [Schneider Children's Medical Center Israel, Section of Anesthesiology (Israel); Superina, Riccardo; Amir, Gabriel [Schneider Children's Medical Center Israel, Section of Pediatric Cardiology (Israel)] [Schneider Children's Medical Center Israel, Section of Pediatric Cardiology (Israel); Shapiro, Rivka [Schneider Children's Medical Center Israel, Section of Gastroenterology (Israel)] [Schneider Children's Medical Center Israel, Section of Gastroenterology (Israel); Birk, Einat [Schneider Children's Medical Center Israel, Section of Pediatric Cardiology (Israel)] [Schneider Children's Medical Center Israel, Section of Pediatric Cardiology (Israel)

2013-12-15

319

Migration and Coiling of Peritoneal Catheter into the Subgaleal Space: A Very Rare Complication of Subgaleoperitoneal Shunt  

PubMed Central

Upward migration of the peritoneal catheter of a subgaleo-peritoneal (SP) shunt and coiling into the subgaleal space is an extremely rare complication of a SP shunt. A 32-year-old male patient visited our hospital presenting with a large skull defect due to a prior craniectomy performed elsewhere. The patient underwent a cranioplasty with methylmetacrylate, but subsequently developed progressive pseudomeningocele and subgaleal cerebrospinal fluid (CSF) collection. The patient underwent CSF diversion via a SP shunt. After SP shunting, the pseudomeningocele disappeared completely. Six months later, the patient presented with progressive scalp swelling. Skull X-ray showed migration and coiling of the distal catheter of the SP shunt. The patient was treated by removing the entire shunt catheter and the dura was covered with a subgaleal flap. We would like to report our experience with a very rare complication of subgaleo-peritoneal shunting. PMID:24527199

Han, Seong-Rok; Choi, Chan-Young

2013-01-01

320

A SQUID gradiometer module with large junction shunt resistors  

NASA Astrophysics Data System (ADS)

A dual-washer superconducting quantum interference device (SQUID) with a loop inductance of 350 pH and two on-washer integrated input coils is designed according to conventional niobium technology. In order to obtain a large SQUID flux-to-voltage transfer coefficient, the junction shunt resistance is selected to be 33 ?. A vertical SQUID gradiometer module with a baseline of 100 mm is constructed by utilizing such a SQUID and a first-order niobium wire-wound antenna. The sensitivity of this module reaches about 0.2 fT/(cm·Hz1/2) in the white noise range using a direct readout scheme, i.e., the SQUID is directly connected to an operational amplifier, in a magnetically shielded room. Some magnetocardiography (MCG) measurements with a sufficiently high signal-to-noise ratio (SNR) are demonstrated.

Qiu, Yang; Liu, Chao; Zhang, Shu-Lin; Zhang, Guo-Feng; Wang, Yong-Liang; Li, Hua; Zeng, Jia; Kong, Xiang-Yan; Xie, Xiao-Ming

2014-08-01

321

Passively minimizing structural sound radiation using shunted piezoelectric materials.  

PubMed

Two methods are presented to determine optimal inductance and resistance values of the shunt circuit across a piezoceramic material, which is bonded to a simply supported plate in order to minimize sound radiation from the plate. The first method (DH) makes use of den Hartog's damped vibration absorber principle. The second method (SM) uses the Sherman Morrison matrix inversion theorem. The effectiveness of each method is compared with regard to minimizing total acoustic sound-power radiation and acoustic pressure at a point. Optimization algorithms and case studies are presented using a linearized model for the piezoceramic and using a nonlinear model for the piezoceramic that accounts for the inherent dielectric hysteresis. Case studies demonstrate that the second method (SM) results in superior performance, under both linear and nonlinear system assumptions. Studies also illustrate that, if the nonlinearity in the system is significant, it must be incorporated in the optimization process. PMID:14587594

Ozer, M Bulent; Royston, Thomas J

2003-10-01

322

Evaluation of CSF shunt patency by means of /sup 99m/Tc DTPA  

SciTech Connect

Evaluation of 192 cerebrospinal fluid shunts was performed using 1 mCi of /sup 99m/Tc DTPA which was injected into the shunt tubing. This was found to be a safe, simple method of evaluating shunt patency. No complications were noted with this procedure, nor was there any documented case of infection related to the injection of the isotope. The sensitivity of the test for evaluation of patency was 97%, specificity 90%, and accuracy 93%. Various patterns of tracer clearance are noted and discussed. The role on this test as an aid in making management decisions is detailed.

Graham, P.; Howman-Giles, R.; Johnston, I.; Besser, M.

1982-08-01

323

Optimization of shunt isolation processing for silicon solar cells via laser and chemical etching  

NASA Astrophysics Data System (ADS)

We employ laser scribing combined with chemical etching process to isolate the shunts in industrial off-spec or non-prime crystalline solar cells. Liquid crystal sheet and Infrared camera measurements have been carried out to reveal the existence of the shunts and hot spot temperature under reverse bias. Following laser scribing with proper laser parameters, chemical etching has been used to further optimize the isolation effect. Through illuminated current-voltage characteristic measurements, the improved open circuit voltage, fill factor and efficiency have been obtained. These results demonstrate that this combined shunt isolation process has great potential for its application in the solar cells.

Hao, H. L.; Zhong, S. H.; Zhang, X.; Shen, W. Z.

2014-08-01

324

Waste Package Neutron Absorber, Thermal Shunt, and Fill Gas Selection Report  

SciTech Connect

Materials for neutron absorber, thermal shunt, and fill gas for use in the waste package were selected using a qualitative approach. For each component, selection criteria were identified; candidate materials were selected; and candidates were evaluated against these criteria. The neutron absorber materials evaluated were essentially boron-containing stainless steels. Two candidates were evaluated for the thermal shunt material. The fill gas candidates were common gases such as helium, argon, nitrogen, carbon dioxide, and dry air. Based on the performance of each candidate against the criteria, the following selections were made: Neutron absorber--Neutronit A978; Thermal shunt--Aluminum 6061 or 6063; and Fill gas--Helium.

V. Pasupathi

2000-01-28

325

Two-port laparoscopic management of a giant pseudocyst complicating ventriculoperitoneal shunt  

PubMed Central

Insertion of a ventriculo-peritoneal (VP) shunt is the most common operative procedure for the treatment of hydrocephalus in children. Of the several causes of shunt malfunction, cerebrospinal fluid (CSF) pseudocyst is relatively uncommon. There are several modalities to treat a CSF pseudocyst. Laparotomy is required, at times, more than once. We managed a patient of CSF pseudocyst with two-port laparoscopy, by deroofing the psuedocyst and repositioning of the shunt. This minimally invasive technique avoids morbidity associated with laparotomy and aids in early recovery. PMID:25197201

Parelkar, Sandesh V.; Sanghvi, Beejal V.; Samala, Devdas S.; Paradkar, Bhupesh A.; Patil, Shalil H.; Oak, Sanjay N.

2014-01-01

326

Failure of peritoneal and gallbladder shunts in a child with craniopharyngioma  

PubMed Central

A 1-year-old girl with craniopharyngioma required external drainage of 40-50 mL/h of cerebrospinal fluid (CSF) after biopsy and cyst fenestration. She developed CSF ascites following insertion of a ventriculoperitoneal (VP) shunt and a distended painful gallbladder following ventriculogallbladder shunt insertion. Revision to a ventriculoatrial shunt was required. This is the first time a craniopharyngioma has been reported to cause increased CSF production. The potential mechanisms of CSF overproduction and the difficulties managing the large volume of CSF in a young child are discussed. PMID:24470818

Woodfield, Julie; Magdum, Shailendra

2013-01-01

327

Testing of cerebrospinal compensatory reserve in shunted and non-shunted patients: a guide to interpretation based on an observational study.  

PubMed Central

OBJECTIVE--To design a computerised infusion test to compensate for the disadvantages of Katzman's lumbar infusion method: inadequate accuracy of estimation of the resistance to cerebrospinal fluid outflow and poor predictive value in normal pressure hydrocephalus. METHODS--Accuracy was improved by intracranial pressure signal processing and model analysis for measurement of cerebrospinal compensatory variable. These include the CSF outflow resistance, brain compliance, pressure-volume index, estimated sagittal sinus pressure, CSF formation rate, and other variables. Infusion may be made into the lumbar space, ventricles, or, when assessing shunt function in vivo, the shunt chamber. RESULTS AND CONCLUSIONS--The computerised test has been used for five years in a multicentre study in 350 hydrocephalic patients of various ages, aetiologies, and states of cerebrospinal compensation. The principles of using the test to characterise different types of CSF circulatory disorders in patients presenting with ventricular dilatation, including brain atrophy and normal and high pressure hydrocephalus, are presented and illustrated. Previous studies showed a positive correlation between cerebrospinal compensatory variables and the results of shunting, but such a prediction remains difficult in idiopathic normal pressure hydrocephalus, particularly in elderly patients. The technique is helpful in the assessment of shunt malfunction, including posture-related overdrainage, over-drainage related to the nocturnal B wave activity, and proximal or distal shunt obstruction. The appendix presents an introduction of the mathematical modelling of CSF pressure volume-compensation included in computerised infusion test software. Images PMID:8778261

Czosnyka, M; Whitehouse, H; Smielewski, P; Simac, S; Pickard, J D

1996-01-01

328

Noninvasive prediction of shunt operation outcome in idiopathic normal pressure hydrocephalus  

PubMed Central

Idiopathic normal pressure hydrocephalus (iNPH) is a syndrome characterized by gait disturbance, cognitive deterioration and urinary incontinence in elderly individuals. These symptoms can be improved by shunt operation in some but not all patients. Therefore, discovering predictive factors for the surgical outcome is of great clinical importance. We used normalized power variance (NPV) of electroencephalography (EEG) waves, a sensitive measure of the instability of cortical electrical activity, and found significantly higher NPV in beta frequency band at the right fronto-temporo-occipital electrodes (Fp2, T4 and O2) in shunt responders compared to non-responders. By utilizing these differences, we were able to correctly identify responders and non-responders to shunt operation with a positive predictive value of 80% and a negative predictive value of 88%. Our findings indicate that NPV can be useful in noninvasively predicting the clinical outcome of shunt operation in patients with iNPH. PMID:25585705

Aoki, Yasunori; Kazui, Hiroaki; Tanaka, Toshihisa; Ishii, Ryouhei; Wada, Tamiki; Ikeda, Shunichiro; Hata, Masahiro; Canuet, Leonides; Katsimichas, Themistoklis; Musha, Toshimitsu; Matsuzaki, Haruyasu; Imajo, Kaoru; Kanemoto, Hideki; Yoshida, Tetsuhiko; Nomura, Keiko; Yoshiyama, Kenji; Iwase, Masao; Takeda, Masatoshi

2015-01-01

329

Noninvasive prediction of shunt operation outcome in idiopathic normal pressure hydrocephalus.  

PubMed

Idiopathic normal pressure hydrocephalus (iNPH) is a syndrome characterized by gait disturbance, cognitive deterioration and urinary incontinence in elderly individuals. These symptoms can be improved by shunt operation in some but not all patients. Therefore, discovering predictive factors for the surgical outcome is of great clinical importance. We used normalized power variance (NPV) of electroencephalography (EEG) waves, a sensitive measure of the instability of cortical electrical activity, and found significantly higher NPV in beta frequency band at the right fronto-temporo-occipital electrodes (Fp2, T4 and O2) in shunt responders compared to non-responders. By utilizing these differences, we were able to correctly identify responders and non-responders to shunt operation with a positive predictive value of 80% and a negative predictive value of 88%. Our findings indicate that NPV can be useful in noninvasively predicting the clinical outcome of shunt operation in patients with iNPH. PMID:25585705

Aoki, Yasunori; Kazui, Hiroaki; Tanaka, Toshihisa; Ishii, Ryouhei; Wada, Tamiki; Ikeda, Shunichiro; Hata, Masahiro; Canuet, Leonides; Katsimichas, Themistoklis; Musha, Toshimitsu; Matsuzaki, Haruyasu; Imajo, Kaoru; Kanemoto, Hideki; Yoshida, Tetsuhiko; Nomura, Keiko; Yoshiyama, Kenji; Iwase, Masao; Takeda, Masatoshi

2015-01-01

330

Potential value of intraoperative Doppler colour flow mapping in operations for complex intracardiac shunting  

Microsoft Academic Search

An eight year old boy presented with multiple residual intracardiac shunts and considerable persisting haemolytic anaemia five years after the repair of a single perimembranous ventricular septal defect. Preoperative transthoracic colour flow mapping showed an \\

G R Sutherland; S Balaji; J L Monro

1989-01-01

331

Transjugular intrahepatic portosystemic stent-shunt: technical factors and new developments.  

PubMed

The introduction of expandable metal stents in the mid 1980s led to the development of transjugular intrahepatic portosystemic stent-shunt (TIPSS) as we know it today. Short-lived detrimental effects on the hyperdynamic circulation in cirrhosis accompany the acute reduction in portal pressure following TIPSS creation. Caution is needed in patients with cardiac dysfunction or pulmonary hypertension. With increasing expertise and careful patient selection, fatal procedural complications are rare and TIPSS can even be safely used as a bridge to liver transplantation. Shunt insufficiency and hepatic encephalopathy are more common following TIPSS. Currently, however, novel approaches to tackling both these limitations exist. These include the combination of uncovered TIPSS with variceal band ligation, and the introduction of polytetrafluoroethylene covered stents. Despite the lack of controlled studies, covered stents are now widely used and have the potential to drastically reduce shunt insufficiency, the need for long-term shunt surveillance and even hepatic encephalopathy. PMID:17033430

Tripathi, Dhiraj; Redhead, Doris

2006-11-01

332

The impact of performing spirometry on shunting across a patent foramen ovale.  

PubMed

Transient changes in intrathoracic pressure can alter left and right intra-atrial pressures, and may provoke shunting of blood across a patent foramen ovale (PFO). Spirometry causes a transient rise and subsequent fall in intrathoracic pressure that, if performed following a dive on compressed air, could raise the risk of decompression illness by arterialisation of venous bubbles across a PFO. To assess whether spirometry can provoke right-to-left shunting across a patent foramen ovale, a subject with a known PFO, previously identified by bubble contrast transthoracic echocardiography, where shunting was only evident on performing a Valsalva manoeuvre, underwent re-examination whilst performing spirometry. Right-to-left shunting was not evident at rest, but was provoked by performing spirometry. If spirometry is to be performed within two hours of surfacing, this should be regarded as a potential risk for decompression illness. PMID:22752742

Maddox, Ian Ec; Smart, David R; Bishop, Warrick Lj

2009-12-01

333

Missed diagnosis of a gallstone ileus: an incomplete laparoscopy due to a putative ventriculoperitoneal shunt infection  

PubMed Central

A 90-year-old woman presented with abdominal pain and vomiting. Initial investigations revealed diffuse abdominal tenderness and fever, combined with leucocytosis and marked elevation of C reactive protein levels. Abdominal CT demonstrated segmental bowel wall thickening in the jejunum near the tip of a ventriculoperitoneal (VP) shunt, which had been placed 17?years before because of hydrocephalus. Pneumobilia was present but no ectopic gallstone was detected at the initial analysis and there were no signs of mechanical ileus. Immediate laparoscopy was performed to exclude small bowel ischaemia. Owing to purulent ascites the VP shunt was externalised, supposing VP shunt infection with reactive jejunitis to be the main problem. Antibiotic treatment was then administered and the remaining part of the shunt was removed 6?days later. However, clinical signs of intestinal obstruction have been aggravated. Therefore, a laparoscopy was repeated 3?days later and a gallstone ileus was diagnosed. After enterolithotomy through a minilaparotomy, the patient was fully recovered. PMID:23563674

Däster, Silvio; Nebiker, Christian A; Hohmann, Joachim; Droeser, Raoul A

2013-01-01

334

Neural Network Based Modeling and Analysis of LP Control Surface Allocation  

NASA Technical Reports Server (NTRS)

This paper presents an approach to interpretive modeling of LP based control allocation in intelligent flight control. The emphasis is placed on a nonlinear interpretation of the LP allocation process as a static map to support analytical study of the resulting closed loop system, albeit in approximate form. The approach makes use of a bi-layer neural network to capture the essential functioning of the LP allocation process. It is further shown via Lyapunov based analysis that under certain relatively mild conditions the resulting closed loop system is stable. Some preliminary conclusions from a study at Ames are stated and directions for further research are given at the conclusion of the paper.

Langari, Reza; Krishnakumar, Kalmanje; Gundy-Burlet, Karen

2003-01-01

335

What are the implications of the spontaneous spleno-renal shunts in liver cirrhosis?  

PubMed Central

Background Although significant advances are expected to be made in the assessment of the portal hypertension-related complications, the prognostic role of spleno-renal shunts has not been fully explored so far. Clarifying this aspect could help tackle the life-treating events occurring in patients suffering from liver cirrhosis. The aim of the study was to analyze the relationships between the spleno-renal shunts presence at doppler ultrasound and the liver cirrhosis complications. Methods Design: eighty one patients out of 129 formed the study population (35 females). Chronic liver damage in these patients was caused by HCV (66), HBV (2), alcohol abuse (2) or unknown etiology, likely non-alcoholic steatohepatitis (11). Setting: two Liver Units of university/primary hospitals in Southern Italy. Main outcome measures: grading of esofageal varices; detection of ascites: assessment of hepatic encephalopathy; evaluation of liver cirrhosis severity; tracking hepatocellular carcinoma; doppler features of spleno-renal shunts and splenic flow velocity; spleen longitudinal diameter at sonography. Results The prevalence of spleno-renal shunts was 18.5%, without no difference concerning the etiology (HCV versus non-HCV, p = 0.870); the prevalence of hepatocellular carcinoma in patients with spleno-renal shunts was superior to that of patients without them (Pearson Chi-square, p = 0.006, power of sample size 74%), also after adjustment for liver decompensation (p = 0.024). The median score of hepatic encephalopathy in patients with and without spleno-renal shunts was similar, i.e., 0 (range, 0-2) versus 0 (0 - 3), p = 0.67. The median splenic vein flow velocity in patients with spleno-renal shunts was significantly inferior to that of patients without them, i.e., 13 cm/sec (95% confidence intervals, 6-18) versus 21 cm/sec (17-24), p < 0.0001. By far the largest percentage of large esophageal varices was in patients without spleno-renal shunts (p = 0.005). In contrast, the frequency of ascites and hepatic encephalopathy severity was overlapping in the two groups. BMI values but not Child-Pugh's classification predicted spleno-renal shunts (Ors = 1.84, 95% confidence intervals = 1.28-2.64, p = 0.001 and 1.145, 95% confidence intervals = 0.77-1.51, p = 0.66). Conclusion Taking into consideration the relatively small sample size, patients with spleno-renal shunts are burdened by an increased incidence of hepatocellular carcinoma. BMI predicted the spleno-renal shunts presence. PMID:19930687

2009-01-01

336

New method for multiple-mode shunt damping of structural vibration using a single piezoelectric transducer  

Microsoft Academic Search

A new multi-mode semi-active shunt technique for controlling vibration in piezoelectric laminated structures is proposed in this paper. The effect of the ``negative capacitor'' controller is studied theoretically and then validated experimentally on a piezoelectric laminated simply-supported beam. The negative capacitor controller is similar in nature to passive shunt damping techniques, as a single piezoelectric transducer is used to dampen

Sam Behrens; Andrew J. Fleming; S. O. Reza Moheimani

2001-01-01

337

Intestinal Perforation in the Context of Thoracoamniotic Shunting and Congenital Diaphragmatic Hernia  

PubMed Central

A fetus was diagnosed by prenatal ultrasound with bilateral intrauterine pleural effusions that were subsequently drained in utero by insertion of bilateral thoracoamniotic shunts. Serial prenatal ultrasound scans were consistent with a left-sided diaphragmatic hernia. On the first day of life, the infant underwent an exploratory laparotomy for intestinal obstruction, with radiographic findings of pneumatosis intestinalis. Intraoperative findings were suggestive of prenatal bowel and diaphragm perforation, which might have occurred as a complication of thoracoamniotic shunting.

Dassios, Theodore; Hassan, Wassim A.; Kazmierski, Marcin; Carroll, Daniel; Ahluwalia, Jag

2013-01-01

338

Superconducting FCL using a combined inducted magnetic field trigger and shunt coil  

DOEpatents

A single trigger/shunt coil is utilized for combined induced magnetic field triggering and shunt impedance. The single coil connected in parallel with the high temperature superconducting element, is designed to generate a circulating current in the parallel circuit during normal operation to aid triggering the high temperature superconducting element to quench in the event of a fault. The circulating current is generated by an induced voltage in the coil, when the system current flows through the high temperature superconducting element.

Tekletsadik, Kasegn D. (Rexford, NY)

2007-10-16

339

Large spleno-caval shunt not accompanied by cirrhosis or encephalopathy  

Microsoft Academic Search

A 40-year-old man with a large spleno-caval shunt through the azygos vein is described. This was considered a rare case, because\\u000a the patient had no accompanying advanced liver disease, or episodes of hepatic encephalopathy. During checks after abnormal\\u000a liver function test results, a shunt vessel was detected incidentally by ultrasonography. Computed tomography, magnetic resonance\\u000a imaging, and angiography demonstrated that it

Hiroshi Mitsui; Naoaki Hashimoto; Masashi Isshiki; Naohiko Masaki; Akihiko Ohno; Hiroshi Imamura; Yasushi Harihara; Kiyoshi Kurokawa

1996-01-01

340

Elevation of intracranial pressure following transjugular intrahepatic portosystemic stent-shunt for variceal haemorrhage  

Microsoft Academic Search

Increased intracranial pressure and cerebral oedema in patients with chronic liver disease is rare and is more typical of acute liver failure. Transjugular intrahepatic portosystemic stent-shunt is being increasingly used in the management of uncontrolled variceal haemorrhage in patients with cirrhosis. In our institution, a total of 160 patients has undergone transjugular intrahepatic porto-systemic stent-shunt for variceal haemorrhage; 56 of

Rajiv Jalan; Kostas Dabos; Doris N. Redhead; Alistair Lee; Peter C. Hayes

1997-01-01

341

Evaluation of Microbial Bacterial and Fungal Diversity in Cerebrospinal Fluid Shunt Infection  

PubMed Central

Background Cerebrospinal fluid shunt infection can be recalcitrant. Recurrence is common despite appropriate therapy for the pathogens identified by culture. Improved diagnostic and therapeutic approaches are required, and culture-independent molecular approaches to cerebrospinal fluid shunt infections have not been described. Objectives To identify the bacteria and fungi present in cerebrospinal fluid from children with cerebrospinal fluid shunt infection using a high-throughput sequencing approach, and to compare those results to those from negative controls and conventional culture. Methods This descriptive study included eight children ?18 years old undergoing treatment for culture-identified cerebrospinal fluid shunt infection. After routine aerobic culture of each cerebrospinal fluid sample, deoxyribonucleic acid (DNA) extraction was followed by amplification of the bacterial 16S rRNA gene and the fungal ITS DNA region tag-encoded FLX-Titanium amplicon pyrosequencing and microbial phylogenetic analysis. Results The microbiota analyses for the initial cerebrospinal fluid samples from all eight infections identified a variety of bacteria and fungi, many of which did not grow in conventional culture. Detection by conventional culture did not predict the relative abundance of an organism by pyrosequencing, but in all cases, at least one bacterial taxon was detected by both conventional culture and pyrosequencing. Individual bacterial species fluctuated in relative abundance but remained above the limits of detection during infection treatment. Conclusions Numerous bacterial and fungal organisms were detected in these cerebrospinal fluid shunt infections, even during and after treatment, indicating diverse and recalcitrant shunt microbiota. In evaluating cerebrospinal fluid shunt infection, fungal and anaerobic bacterial cultures should be considered in addition to aerobic bacterial cultures, and culture-independent approaches offer a promising alternative diagnostic approach. More effective treatment of cerebrospinal fluid shunt infections is needed to reduce unacceptably high rates of reinfection, and this work suggests that one effective strategy may be reduction of the diverse microbiota present in infection. PMID:24421877

Simon, Tamara D.; Pope, Christopher E.; Browd, Samuel R.; Ojemann, Jeffrey G.; Riva-Cambrin, Jay; Mayer-Hamblett, Nicole; Rosenfeld, Margaret; Zerr, Danielle M.; Hoffman, Lucas

2014-01-01

342

The collateral caval shunt as an alternative to classical shunt procedures in patients with recurrent duodenal varices and extrahepatic portal vein thrombosis  

PubMed Central

Upper gastrointestinal bleeding episodes from variceal structures are severe complications in patients with portal hypertension. Endoscopic sclerotherapy and variceal ligation are the treatment options preferred for upper variceal bleeding owing to extrahepatic portal hypertension due to portal vein thrombosis (PVT). Recurrent duodenal variceal bleeding in non-cirrhotic patients with diffuse porto-splenic vein thrombosis and subsequent portal cavernous transformation represent a clinical challenge if classic shunt surgery is not possible or suitable. In this study, we represent a case of recurrent bleeding of duodenal varices in a non-cirrhotic patient with cavernous transformation of the portal vein that was successfully treated with a collateral caval shunt operation. PMID:24965047

2014-01-01

343

Mechanism for measurement of flow rate of cerebrospinal fluid in hydrocephalus shunts.  

PubMed

The measurement of the flow rate of cerebrospinal fluid (CSF) or existence of CSF flow inside the shunt tube after shunt implant have been reported as tedious process for both patients and doctors; this paper outlines a potential in vitro flow rate measurement method for CSF in the hydrocephalus shunt. The use of implantable titanium elements in the shunt has been proposed to allow for an accurate temperature measurement along the shunt for prediction of CSF flow rate. The CSF flow velocity can be deduced by decoupling the thermal transfer in the measured differential time at a pair of measurement spots of the titanium elements. Finite element analyses on the fluidic and thermal behaviors of the shunt system have been conducted. Preliminary bench-top measurements on a simulated system have been carried out. The measured flow rates, ranging from 0.5 mm/sec to 1.0 mm/sec, which is clinically practical, demonstrate good agreements with the simulation results. PMID:25570411

Rajasekaran, Sathish; Kovar, Spencer; Qu, Peng; Inwald, David; Williams, Evan; Qu, Hongwei; Zakalik, Karol

2014-01-01

344

Distal splenorenal shunt for management of variceal bleeding in patients with schistosomal hepatic fibrosis.  

PubMed Central

The distal splenorenal shunt was performed in 60 patients with schistosomal hepatic fibrosis in whom no evidence of cirrhosis was documented by preoperative needle and operative wedge biopsy. No patients have been lost to follow-up with a median of 37 months (range: 17-86). The results showed low operative mortality (1.7%), high patency rate (92.5%), and low recurrent variceal hemorrhage (6.7%). Thrombosed shunts were treated either by refashioning the shunt (1 patient) or splenectomy and gastric devascularization (2 patients). Initial hyperbilirubinemia and reduction in serum albumin were found in the early postoperative period, with persistent hyperbilirubinemia in 32% of the patients. The 5-year survival was 88%, with liver disease related mortality in only three patients. Clinical encephalopathy was detected in three patients (5.1%); only one of them was incapacitated. These data showed that: selective shunt (distal splenorenal shunt, DSRS) is an effective surgical procedure in the treatment of schistosomal variceal bleeding, shunt thrombosis is rare and can possible be corrected if detected early, schistosomal patients have a better survival and a lower incidence of encephalopathy after DSRS than that reported in cirrhotics, and liver biopsy should be performed for proper assessment of the schistosomal population especially in the geographic areas where the schistosoma parasite and viral hepatitis are endemic. Images FIG. 1. FIG. 2. FIG. 4. FIG. 5. FIG. 6. PMID:3767488

Ezzat, F A; Abu-Elmagd, K M; Aly, I Y; Aly, M A; Fathy, O M; el-Barbary, M H; Bahgat, O O; Salam, A A; Kutner, M H

1986-01-01

345

76 FR 12103 - Erie Boulevard Hydropower, L.P; Notice of Settlement Agreement and Soliciting Comments  

Federal Register 2010, 2011, 2012, 2013, 2014

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2011-03-04

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2011-10-21

350

Characterization of LpGPAT Gene in Lilium pensylvanicum and Response to Cold Stress  

PubMed Central

LpGPAT was obtained from L. pensylvanicum using RT-PCR and rapid amplification of cDNA ends. The cloned full-length cDNA was 1544?bp; it encoded 410 amino acids and had a molecular size of 46?KDa. The nucleic acid sequence analysis showed that it shared high homology with other known GPATs. SMAT result suggests that there is a PlsC that exists in 176-322 amino acid sequence of LpGAPT; it means LpGPAT protein is a member of the family of acyltransferase and has acyltransferase enzymatic activity. Result of real-time quantitative PCR and semiquantitative PCR support LpGPAT gene is definitely induced by low temperature stress. PMID:25710023

Sun, Shao-kun; Yang, Ni-na; Chen, Li-jing; Irfan, Muhammad; Zhao, Xing-hua; Li, Tian-lai

2015-01-01

351

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2012-12-18

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2010-07-02

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2013-05-06

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2013-03-19

358

L(p) regularization for early gate fluorescence molecular tomography.  

PubMed

Time domain fluorescence molecular tomography (TD-FMT) provides a unique dataset for enhanced quantification and spatial resolution. The time-gate dataset can be divided into two temporal groups around the maximum counts gate, which are early gates and late gates. It is well established that early gates allow for improved spatial resolution and late gates are essential for fluorophore unmixing and concentration quantification. However, the inverse problem of FMT is ill-posed and typically underdetermined, which makes image reconstruction highly susceptible to data noise. More specifically, photon counts are inherently very low at early gates due to high absorption and scattering of tissue, resulting in a low signal-to-noise ratio and unstable reconstructions. In this work, an L(p) regularization-based reconstruction algorithm was developed and tested with our wide-field mesh-based Monte Carlo simulation strategy. We compared the early time-gate reconstructions obtained with the different p (p?{1/16,1/8,1/4,1/3,1/2,1,2}) from a synthetic murine model simulating the fluorophore uptake in the kidneys and preclinical data. The results from a 3D mouse atlas and a mouse experiment show that our L(1/4) regularization methods give the best performance for early time gates reconstructions. PMID:25121675

Zhao, Lingling; Yang, He; Cong, Wenxiang; Wang, Ge; Intes, Xavier

2014-07-15

359

Effects of isradipine and other calcium antagonists on arteriovenous-shunt flow in anesthetized rabbits and cats  

SciTech Connect

The effects of vasodilators on arteriovenous (AV)-shunt flow was investigated in anesthetized cats and rabbits, using the tracer microsphere method. In cats, the calcium antagonist isradipine reduced AV-shunt flow; verapamil showed a similar tendency and nicardipine was without effect. Dihydralazine strongly increased, but nitroglycerin and dipyridamole decreased AV-shunt flow. In rabbits, the effects of isradipine and verapamil were similar to those seen in cats. Sodium nitroprusside had no effect, whereas prazosin, minoxidil, and the potassium-channel activator cromakalim increased AV-shunt flow. The contrasting effects of drugs sharing the same mechanism of action suggest that target-tissue selectivity is more important than the mechanism of action. An increase of AV-shunt flow is unlikely to be beneficial but could be associated with a number of undesirable side effects. It might negatively affect migraine sufferers and, if AV-shunt dilatation shows no tolerance development, it represents an unnecessary hemodynamic burden for the heart.

Hof, R.P.

1989-04-17

360

Hyperglucagonemia and hyperkinetic circulation after portocaval shunt in the rat  

SciTech Connect

The study was aimed at investigating whether increased portal venous inflow (PVI) after portocaval shunt (PCS) in the rat is the result of selective splanchnic vasodilatation or whether it is part of a generalized circulatory disturbance. Rats with PCS and sham-operated controls were studied 2 wk after surgery by measuring cardiac output (CO), PVI, and hepatic artery flow (HAF) with radioactive microspheres (V Cr and UC). Plasma glucagon (GL) was measured by radioimmunoassay. PCS rats had increased CO and reduced arterial pressure and total peripheral resistance. PVI was markedly increased, but this appeared to be part of a generalized circulatory disturbance, since when PVI is expressed as percent of CO no difference is observed between PCS and sham-operated rats, indicating the absence of a preferential splanchnic vasodilatation. GL increased after PCS, and significant correlations were observed between GL and CO and between GL and PVI. HAF increased after PCS but did not compensate the loss of portal flow, evidence by a lower total hepatic flow in PCS rats. These results suggest that PCS induces a hyperkinetic circulatory state in which increased PVI represents its splanchnic manifestation and that increased GL release may be in part responsible for these hemodynamic changes.

Kravetz, D.; Arderiu, M.; Bosch, J.; Fuster, J.; Visa, J.; Casamitjana, R.; Rodes, J.

1987-02-01

361

Inherited congenital extrahepatic portosystemic shunts in Cairn terriers.  

PubMed

The pathogenesis of congenital portosystemic shunt (CPSS) in dogs still is incompletely understood. In Irish Wolfhounds and Yorkshire Terriers, CPSS is reported to be hereditary. The aim of this study was to investigate a possible genetic basis and the mode of inheritance of CPSS in Cairn Terriers. Between July 1990 and July 2001, 6-week-old pups of the Dutch Cairn Terrier population were screened by measuring venous ammonia concentrations and in the presence of hyperammonemia by ultrasonography, autopsy, portal vein angiography, or exploratory celiotomy. The same successfully operated female was used 3 times in test matings with an unrelated affected male, her unaffected sire, and an affected offspring. The prevalence of CPSS in the general Cairn Terrier population, the direct progeny of frequently used males, and the offspring of the test matings were tested for significant differences. In total, 6,367 Cairn Terriers were screened; 32 males and 26 females had CPSS. In 3 large family groups, significantly higher prevalences were found compared with the general population (P < .0001, P < .0001, and P < .044). The prevalence of CPSS in the offspring of the test matings was significantly higher (P < .002) than in the general population. No sex predisposition occurred among the affected dogs. The higher prevalence of CPSS in the test matings and the 3 family groups compared with the general population indicates that CPSS in Cairn Terriers is a genetic disease. The inheritance is autosomal and most likely polygenic or monogenic with variable expression. PMID:15954545

van Straten, G; Leegwater, P A J; de Vries, M; van den Brom, W E; Rothuizen, J

2005-01-01

362

Scaling of electromagnetic transducers for shunt damping and energy harvesting  

NASA Astrophysics Data System (ADS)

In order for an electromagnetic transducer to operate well as either a mechanical shunt damper or as a vibration energy harvester, it must have good electromechanical coupling. A simple two-port analysis is used to derive a non-dimensional measure of electromechanical coupling, which must be large compared with unity for efficient operation in both of these applications. The two-port parameters for an inertial electromagnetic transducer are derived, from which this non-dimensional coupling parameter can be evaluated. The largest value that this parameter takes is approximately equal to the square of the magnetic flux density times the length of wire in the field, divided by the mechanical damping times the electrical resistance. This parameter is found to be only of the order of one for voice coil devices that weigh approximately 1 kg, and so such devices are generally not efficient, within the definition used here, in either of these applications. The non-dimensional coupling parameter is found to scale in approximate proportion to the device's characteristic length, however, and so although miniaturised devices are less efficient, greater efficiency can be obtained with large devices, such as those used to control civil engineering structures.

Elliott, Stephen J.; Zilletti, Michele

2014-04-01

363

Intravenous spiral support for the prevention of outflow-tract stenosis in av-shunts for hemodialysis?  

PubMed

Intraluminal spiral support of bovine heterografts (Solcograft-P) offers promising mechanical characteristics for av-shunts. Using a tunneling technique the spiral prevents twisting and kinking during subcutaneous placement and allows prolonged and vigorous post-puncture compression for hemostasis without compromising shunt flow. Canine experiments (femoro-femoral loop) suggest that additional insertion of the spiral into the efferent vein for some centimeters can prevent or delay the development of outflow-tract stenosis, the main cause of late shunt failure (0% (0/5) vs. 75% (3/4) significant stenosis; total patency rate 90% (9/10); follow-up 3 months). Preliminary clinical results with brachio-cephalic/basilic av-shunts in the forearm (loop) support our experimental investigations. In all eight patients the shunt is functioning perfectly without reinterventions being necessary (mean follow-up 8.8 months, totally 55 dialysis months). In five patients the shunt was used early for hemodialysis (days 1-10 post operation). Angiographically, stenoses developed in the outflow-tract in five of six shunts, but only one stenosis was observed in the spiral-supported venous segment where it usually occurs. In some cases shunt function was preserved by collaterals from the nonstenotic spiral-supported venous segment despite occlusion of the main efferent vein. Thus, it appears that a spiral placed into the graft and efferent vein is suitable to prolong the functional life of av-shunts. PMID:3969522

Maass, D; Binswanger, U; Rausis, C; Uhlschmid, G K; Largiadèr, F

1985-01-01

364

Post-TIPS Hepatic Encephalopathy Treated by Occlusion Balloon-Assisted Retrograde Embolization of a Coexisting Spontaneous Splenorenal Shunt  

SciTech Connect

A 51-year-old man with posthepatitis cirrhosis underwent a transjugular intrahepatic portosystemic shunt (TIPS) for bleeding of recurrent esophageal varices. The patient had a coexisting, spontaneous, splenorenal shunt. He subsequently developed hepatic encephalopathy, presumably due to excessive portosystemic shunting. Since medical management resulted in no significant improvement, the splenorenal shunt was embolized from the jugular vein approach via renal vein access during temporary balloon occlusion. Within a few days, the patient's hepatic encephalopathy resolved. Twelve months later the patient showed no recurrence of encephalopathy and had maintained a patent TIPS.

Shioyama, Yasukazu; Matsueda, Kiyoshi; Horihata, Koushi; Kimura, Masashi [Department of Radiology, Central Hospital and Cancer Center of Ibaraki Prefecture, 6528 Koibuchi Tomobe-machi, Nishiibaraki-gun, Ibaraki, Japan 309-17 (Japan); Nishida, Norifumi; Kishi, Kazushi; Terada, Masaki; Sato, Morio; Yamada, Ryusaku [Department of Radiology, Wakayama Medical College, 27 7-bancho, Wakayama-shi, Wakayama, Japan 640 (Japan)

1996-11-15

365

T1-201 per rectum: A noninvasive method for evaluating portosystemic shunt  

SciTech Connect

Portosystemic shunt is one of the most important complications of liver cirrhosis. Unfortunately, current methods for detecting and quantifying this shunt are either non-specific or associated with significant morbidity. The aim of this work was to evaluate the clinical value of a new non-traumatic method which consisted of administrating T1-201 per rectum and monitoring the absorbed activity using a camera and a computer system. The method assumes that in the absence of portosystemic shunt, most of the absorbed activity will be fixed in the liver while in the presence of this shunt, some of the activity will be fixed in the myocardium. The ratio of heart to liver activity can therefore be used to evaluate the importance of the portosystemic shunt. 34 subjects have been studied. The ratio of heart to liver activity at the 25th minute after the tracer administration is higher in patients with liver cirrhosis (n=22, m=.9, s.d.=.37) than in patients with steatosis (n=10, m=.28, s.d.=.03). In two healthy subjects investigated the H/L ratio was .27 and .30. The reproducibility of the test was evaluated in 8 subjects and showed a good reproducibility (mean of difference =.03, range=.01 to .07). Patients with esophageal varices had always a high H/L ratio while some patients with liver cirrhosis without esophageal varices had also high H/L ratio, probably due to the presence of intrahepatic shunt. The authors' results showed the value of this new non-traumatic test for detecting and quantifying extra- as well as intrahepatic portosystematic shunt.

Verdickt, X.; Reding, P.; Tshiamala, P.; Ham, H.R.

1984-01-01

366

[CT in normal pressure hydrocephalus--correlation between CT and clinical response to shunting (author's transl)].  

PubMed

CT scans were obtained on 33 patients (age 73y. to 31y.) with the diagnosis of normal pressure hydrocephalus. In each case, the diagnosis was made on the basis of the symptoms, CT and cisternographic findings. Underlying diseases of normal pressure hydrocephalus are ruptured aneurysms (21 cases), arteriovenous malformations (2 cases), head trauma (1 case), cerebrovascular accidents (1 case) and idiopathy (8 cases). Sixteen of 33 patients showed marked improvement, five, moderate or minimal improvement, and twelve, no change. The results were compared with CT findings and clinical response to shunting. CT findings were classified into five types, bases on the degree of periventricular hypodensity (P.V.H.), the extent of brain damage by underlying diseases, and the degree of cortical atrophy. In 17 cases of type (I), CT shows the presence of P.V.H. with or without minimal frontal lobe damage and no cortical atrophy. The good surgical improvements were achieved in all cases of type (I) by shunting. In 4 cases of type (II), CT shows the presence of P.V.H. and severe brain damage without cortical atrophy. The fair clinical improvements were achieved in 2 cases (50%) by shunting. In one case of type (III), CT shows the absence of P.V.H. without brain damage nor cortical atrophy. No clinical improvement was obtained by shunting in this type. In 9 cases of type (IV) with mild cortical atrophy, the fair clinical improvement was achieved in two cases (22%) and no improvement in 7 cases. In 2 cases of type (V) with moderate or marked cortical atrophy, no clinical improvement was obtained by shunting. In conclusion, it appeared from the present study that there was a good correlation between the result of shunting and the type of CT, and clinical response to shunting operation might be predicted by classification of CT findings. PMID:7242797

Fujita, K; Nogaki, H; Noda, M; Kusunoki, T; Tamaki, N; Matsumoto, S

1981-02-01

367

In vitro hydrodynamic properties of the Miethke proGAV hydrocephalus shunt  

PubMed Central

Background Adjustable shunts are very popular in the management of hydrocephalus and are believed to help in minimizing the number of surgical revisions. The drawback with almost all constructions is that they may be accidentally readjusted in relatively weak magnetic fields (around 30–40 mTesla) Materials and methods The ProGav Miethke shunt is composed of an adjustable ballon-spring valve unit and an integrated over-drainage compensating gravitational device (known as the shunt assistant). A mechanical 'brake' is intended to prevent changes to the valve's performance level in a strong magnetic field. We evaluated the performance and hydrodynamic properties of a sample of three valves in the UK Shunt Evaluation Laboratory. Results All the shunts showed good mechanical durability over the three-month period of testing, and good stability of hydrodynamic performance over a one-month period The pressure-flow performance curves, operating, opening and closing pressures fell within the limits specified by the manufacturer, and changed according to the programmed performance levels. The operating pressure increased when the shunt assistant was in the vertical position, as specified. The valve has a low hydrodynamic resistance (0.53 mm mmHg ml-1 min-1). External programming proved to be easy and reliable. Strong magnetic fields from a 3 Tesla MR scanner were not able to change the programming of the valve. Conclusion The ProGAV shunt is an adjustable, low resistance valve that is able to limit posture-related over-drainage. Unlike other adjustable valves, the ProGAV cannot be accidentally re-adjusted by external magnetic field such as a 3T MR scanner. PMID:16808836

Allin, David M; Czosnyka, Zofia H; Czosnyka, Marek; Richards, Hugh K; Pickard, John D

2006-01-01

368

Simulations reveal adverse hemodynamics in patients with multiple systemic to pulmonary shunts.  

PubMed

For newborns diagnosed with pulmonary atresia or severe pulmonary stenosis leading to insufficient pulmonary blood flow, cyanosis can be mitigated with placement of a modified Blalock-Taussig shunt (MBTS) between the innominate and pulmonary arteries. In some clinical scenarios, patients receive two systemic-to-pulmonary connections, either by leaving the patent ductus arteriosus (PDA) open or by adding an additional central shunt (CS) in conjunction with the MBTS. This practice has been motivated by the thinking that an additional source of pulmonary blood flow could beneficially increase pulmonary flow and provide the security of an alternate pathway in case of thrombosis. However, there have been clinical reports of premature shunt occlusion when more than one shunt is employed, leading to speculation that multiple shunts may in fact lead to unfavorable hemodynamics and increased mortality. In this study, we hypothesize that multiple shunts may lead to undesirable flow competition, resulting in increased residence time (RT) and elevated risk of thrombosis, as well as pulmonary overcirculation. Computational fluid dynamics-based multiscale simulations were performed to compare a range of shunt configurations and systematically quantify flow competition, pulmonary circulation, and other clinically relevant parameters. In total, 23 cases were evaluated by systematically changing the PDA/CS diameter, pulmonary vascular resistance (PVR), and MBTS position and compared by quantifying oxygen delivery (OD) to the systemic and coronary beds, wall shear stress (WSS), oscillatory shear index (OSI), WSS gradient (WSSG), and RT in the pulmonary artery (PA), and MBTS. Results showed that smaller PDA/CS diameters can lead to flow conditions consistent with increased thrombus formation due to flow competition in the PA, and larger PDA/CS diameters can lead to insufficient OD due to pulmonary hyperfusion. In the worst case scenario, it was found that multiple shunts can lead to a 160% increase in RT and a 10% decrease in OD. Based on the simulation results presented in this study, clinical outcomes for patients receiving multiple shunts should be critically investigated, as this practice appears to provide no benefit in terms of OD and may actually increase thrombotic risk. PMID:25531794

Esmaily-Moghadam, Mahdi; Murtuza, Bari; Hsia, Tain-Yen; Marsden, Alison

2015-03-01

369

Coupling of low-order LP modes propagating in cylindrical waveguides into whispering gallery modes in microspheres.  

PubMed

Whispering gallery modes in microspheres are excited by light delivered to them via optical fibers imbedded in a half-block coupler. The corresponding light intensity resonances in microspheres and coupling of two low-order linearly polarized modes in the fibers, LP?? and LP??, into the microspheres are observed. The LP?? and LP?? modes are delivered to the microsphere via a cylindrical optical fiber carrying light at two operating wavelengths, 1550 and 1300 nm correspondingly. The resonances behavioral differences generated by these fiber modes are also observed and explained. The properties of resonances generated by the LP?? and LP?? modes are analyzed using a linear polarizer inserted in the path of light propagating in optical fibers. PMID:23389207

Adamovsky, G; Wrbanek, S

2013-01-28

370

[Role of right-to-left atrial shunt in exercise tolerance of patients with Ebstein anomaly].  

PubMed

The aim of this study was to assess cardiorespiratory tolerance to exercise in children with non-operated, paucisymptomatic and untreated froms of Ebstein's anomaly. The authors undertook a prospective study in 11 children, mean age 9.6 years, who had lung function tests, cardiorespiratory exercise stress tests (bicycle ergometry N = 8, treadmill N = 3) and contrast echocardiography. All parameters of spirometry were normal. Contrast echocardiography showed a right-to-left interatrial shunt in 7 children (group 1) whereas the remaining 4 children had no shunt (group 2). The resting oxygen saturation was 97.4 +/- 2%, with no difference between the two groups. On the other hand, oxygen saturation at peak VO2 (VO2 max) was 90 +/- 9.5%, significantly lower in group 1 than in group 2 (85.7 +/- 2.2% vs 98.2 +/- 1.2%; p = 0.03). In group 1, the VO2 max was correlated to oxygen saturation (r = 0.98; p < 0.001, N = 6). The oxygen desaturation was correlated with presence of a right-to-left interatrial shunt (p = 0.01). The reduced exercise tolerance of non-operated, paucisymptomatic children with Ebstein's anomaly is due to a right-to-left interatrial shunt. In patients with poor exercise tolerance, contrast echocardiography is advised for the detection of these atrial shunts. PMID:10367080

Lupoglazoff, J M; Magnier, S; Kabaker, M; Riescher, B; Benali, K; Prioux, E; Gaultier, C; Casasoprana, A

1999-05-01

371

Long-term results of small-diameter proximal splenorenal venous shunt: A retrospective study  

PubMed Central

AIM: To investigate recurrent variceal hemorrhage and long-term survival rates of patients treated with partial proximal splenorenal venous shunt. METHODS: Patients with variceal hemorrhage who were treated with small-diameter proximal splenorenal venous shunt in Ruijin Hospital between 1996 and 2009 were included in this study. Shunt diameter was determined before operation using Duplex Doppler ultrasonography. Peri-operative and long-term results in term of rehemorrhage, encephalopathy and mortality were followed up. RESULTS: Ninety-eight patients with Child A and B variceal hemorrhage received small-diameter proximal splenorenal venous shunt with a diameter of 7-10 mm. After operation, the patients’ mean free portal pressure (P < 0.01) and the flow rate of main portal vein (P < 0.01) decreased significantly compared with that before operation. The rates of rebleeding and mortality were 6.12% (6 cases) and 2.04% (2 cases), respectively. Ninety-one patients were followed up for 7 mo-14 years (median, 48.57 mo). Long-term rates of rehemorrhage and encephalopathy were 4.40% (4 cases) and 3.30% (3 cases), respectively. Thirteen patients (14.29%) died mainly due to progressive hepatic dysfunction. Five- and ten-year survival rates were 82.12% and 71.24%, respectively. CONCLUSION: Small-diameter proximal splenorenal venous shunt affords protection against variceal rehemorrhage with a low occurrence of encephalopathy in patients with normal liver function. PMID:21876638

Chen, Hao; Yang, Wei-Ping; Yan, Ji-Qi; Li, Qin-Yu; Ma, Di; Li, Hong-Wei

2011-01-01

372

Rex shunt for portal vein thrombosis after adult living donor liver transplantation.  

PubMed

Portal vein thrombosis (PVT) after liver transplantation is a relatively common but serious complication which could lead to portal hypertension or a direct graft loss. A "Rex" shunt created between the superior mesenteric vein (SMV) and the umbilical portion of the left portal vein can be a useful option to treat PVT after pediatric liver transplantation, however, its application to adult patients has not been reported so far because appropriate vein grafts are hardly available. Herein we present a case of PVT after left lobe living donor liver transplantation (LDLT) who underwent the procedure using the own inferior jugular vein and the gonadal vein as a shunt graft. The shunt was patent immediately after the procedure but was thrombosed 2 days after probably due to the insufficient inflow from the SMV and the absence of anticoagulation therapy, for which emergent thrombectomy and ligation of the significant hepatofugal collateral veins followed by full anti-coagulation therapy were performed. The shunt remains open at 8 month after the procedure with a normal anmonia level and liver function. In conclusion, the Rex shunt using recipient's autologous vein grafts is a feasible and valuable option for adult patients to treat PVT after LDLT. PMID:24620643

Soejima, Yuji; Shirabe, Ken; Yoshizumi, Tomoharu; Uchiyama, Hideaki; Ikegami, Toru; Yamashita, Yo-Ichi; Ikeda, Tetsuo; Kawanaka, Hirofumi; Sugimachi, Keishi; Mimori, Koshi; Watanabe, Masayuki; Morita, Masaru; Oki, Eiji; Saeki, Hiroshi; Maehara, Yoshihiko

2013-11-01

373

Kidney plays a major role in ammonia homeostasis after portasystemic shunting in patients with cirrhosis.  

PubMed

The kidney plays an important role in ammonia metabolism. In this study the hypothesis was tested that the kidney can acutely diminish ammonia release after portacaval shunting. Thirteen patients with cirrhosis (6 female/7 male, age 54.4 +/- 3.3 yr) were studied. Blood was sampled prior to and 1 h after transjugular intrahepatic stent-shunt (TIPSS) insertion from the portal vein, a hepatic vein, the right renal vein, and the femoral vein, and renal and liver plasma flow were measured. Prior to TIPSS, renal ammonia release was significantly higher than ammonia release from the splanchnic region, which was not significantly different from zero. TIPSS insertion did not change arterial ammonia concentration or ammonia release from the splanchnic region but reduced renal ammonia release into the circulation (P < 0.05) to values that were not different from zero. TIPSS resulted in a tendency toward increased venous-arterial ammonia concentration differences across leg muscle. Post-TIPSS ammonia efflux via portasystemic shunts was estimated to be seven times higher than renal efflux. Kidneys have the ability to acutely diminish systemic ammonia release after portacaval shunting. Diminished renal ammonia release and enhanced muscle ammonia uptake are important mechanisms by which the cirrhotic patient maintains ammonia homeostasis after portasystemic shunting. PMID:16455791

Olde Damink, Steven W M; Dejong, Cornelis H C; Deutz, Nicolaas E P; Redhead, Doris N; Hayes, Peter C; Soeters, Peter B; Jalan, Rajiv

2006-08-01

374

Lactobacillus paracasei Lp6 favors immune modulation induced by allergoid treatment in ragweed sensitized mice.  

PubMed

It has been hypothesized that lactic acid bacteria (LAB) could be used as adjuvant for specific immunotherapy (SIT), as various studies conducted on humans and animals converge to define LAB as anti-Th2 modulators and Treg inducers. In the present study we evaluated the effects of LAB, in particular Lactobacillus paracasei Lp6 (Lp6), in a mouse model of ragweed (RW) allergy. Groups of Balb/c mice, experimentally sensitized towards ragweed, were treated by viable Lp6 or by RWallergoid with or without co-administration of Lp6. A control group was sham-sensitized with PBS and sham-treated with water and a group was sensitized with RW and treated with water. Serum IgE, RW-induced release of IFN-gamma, IL-4 and IL-10 from splenocytes and the frequency of CD4CD25 regulatory T cells (Tregs) expressing Foxp3 or IL-10 were evaluated in various groups. RW-allergoid treatment induced a reduction of serum IgE, with a decrease in RW-induced release of IL-4, and an increase in IL-10 and IFN-gamma, along with a significant change in the frequency of Tregs, both CD25+ and -. The joint RWallergoid+ Lp6 treatment induced the highest degree of suppression of allergen-driven IL-4, the greatest reduction of IL-4/IFN-gamma and IL-4/IL-10 ratios and the most significant increase of Foxp3 and IL-10 expressing Tregs. The study shows that Lp6 strengthens the immune modulation induced by allergoid-SIT in RW-sensitized mice, essentially characterized by a differential induction of Tregs associated to a reduction of IL-4; data converge to define a role of SIT adjuvant for Lp6. PMID:22230395

Petrarca, C; Lazzarin, F; Lanuti, P; Marchisio, M; Miscia, S; Rossi, C; Braga, M; Mistrello, G; Di Gioacchino, M

2011-01-01

375

Ethnicity may be a reason for lipid changes and high Lp(a) levels in rheumatoid arthritis  

Microsoft Academic Search

There are so many studies that suggest the changes in lipid profiles and lipoprotein (a) [Lp(a)] are associated with early\\u000a atherosclerosis in rheumatoid arthritis (RA). But there are some opposite studies also. Because of marked ethnicity differences\\u000a in the distribution of Lp(a), we aimed to investigate the associations of Lp(a) levels and lipid changes in Turkish RA patients.\\u000a There were

Mustafa Cesur; Zeynep Ozbalkan; Mehtap Akcil Temel; Ya?ar Karaarslan

2007-01-01

376

PI and fuzzy logic controllers for shunt Active Power Filter--a report.  

PubMed

This paper presents a shunt Active Power Filter (APF) for power quality improvements in terms of harmonics and reactive power compensation in the distribution network. The compensation process is based only on source current extraction that reduces the number of sensors as well as its complexity. A Proportional Integral (PI) or Fuzzy Logic Controller (FLC) is used to extract the required reference current from the distorted line-current, and this controls the DC-side capacitor voltage of the inverter. The shunt APF is implemented with PWM-current controlled Voltage Source Inverter (VSI) and the switching patterns are generated through a novel Adaptive-Fuzzy Hysteresis Current Controller (A-F-HCC). The proposed adaptive-fuzzy-HCC is compared with fixed-HCC and adaptive-HCC techniques and the superior features of this novel approach are established. The FLC based shunt APF system is validated through extensive simulation for diode-rectifier/R-L loads. PMID:21982358

P, Karuppanan; Mahapatra, Kamala Kanta

2012-01-01

377

Multimodality cardiac imaging of a double chambered right ventricle with intrapulmonary shunting: a case report  

PubMed Central

Background Double chambered right ventricle (DCRV) is a relatively rare congenital heart disease, characterized by the abnormal division of the right ventricle into a high-pressure inlet and low-pressure outlet by anomalous muscle bundles. Extra-cardiac right-to-left shunts may present with clinical symptoms in adulthood and should be sought in patients with previous cavo-pulmonary shunt procedures. Case presentation We report a case of DCRV in a 29 year old Caucasian male presenting in adulthood with a right-to-left shunt secondary to venous collaterals, following cavopulmonary anastomosis for congenital pulmonary atresia and hypoplastic right ventricle. Conclusion Multimodality cardiac imaging using echocardiography, cardiac CT, cardiac MRI and cardiac catheterization is often required for complete characterization of complex congenital heart anomalies in adulthood. PMID:22999111

2012-01-01

378

A case of pulmonary arterial hypertension associated with congenital extrahepatic portocaval shunt.  

PubMed

Congenital extrahepatic portocaval shunt (CEPS) is a rare anomaly of the mesenteric vasculature in which the intestinal and splenic venous drainage bypasses the liver and drains directly into the inferior vena cava, the left hepatic vein or the left renal vein. This uncommon disease is frequently associated with other malformations and mainly affects females. Here we report a case of pulmonary arterial hypertension associated with CEPS (Abernethy type 1b shunt) in a 20-yr-old man who was incidentally diagnosed during evaluation of multiple nodules of the liver. The patient was treated by inhalation of iloprost (40 µg/day) with improved condition and walking test. Physicians should note that congenital portocaval shunt may cause pulmonary hypertension. PMID:24753712

Yi, Jeong-Eun; Jung, Hae-Ok; Youn, Ho-Joong; Choi, Jong Young; Chun, Ho Jong; Lee, Jae Young

2014-04-01

379

A Shunt Model of the Inner Medullary Nephron with Pre-Bend Transitions  

NASA Astrophysics Data System (ADS)

Mathematical models of the renal medulla face the problem of representing water and solute transfer among tens of thousands of nephrons and blood vessels of various lengths, arranged in countercurrent fashion. Published models fall into two broad categories with respect to this issue: multi-nephron models, which explicitly represent a large number of individual nephrons, or lumped models with virtual shunts that represent the turning back of nephrons and vessels at varying depths. Shunt models have the advantage of a compact description and relatively rapid execution time but are ill-suited to faithfully represent features such as prebend transitions of epithelial permeabilities in nephrons of different lengths. A new shunt model approach that can accommodate pre-bend transitions of nephrons at all medullary depths is presented in this work together with the results of simulation of predicted flows and concentrations.

Gonzalez, M. T.; Hegarty, A. F.; Thomas, S. R.

2009-09-01

380

Destruction of LP XM46 using the molten salt destruction process. Revision 1  

SciTech Connect

The preliminary experimental work done on the destruction of the liquid gun propellant LP XM46 (the new designation for LGP-1846) using the Molten Salt Destruction (MSD) Process at the Lawrence Livermore National Laboratory (LLNL) for the US Army is described in this report. A series of 18 continuous experimental runs were made wherein a solution of LP XM46 and water was injected into a bed of molten salt comprising the carbonates of sodium, potassium and lithium, along with air. The purpose of these initial Phase 1 runs was to collect information on the applicability of the Molten Salt Destruction Process for the destruction of LP XM46, identify the key technical uncertainties, and to plan future runs. The tentative results from these experiments, described in detail in the main body of this report, indicate that: (1) LP XM46 can be safely and completely destroyed in a bed of molten salt at temperatures well below those needed for incineration; and (2) under optimum operating conditions, less than 1% of the chemically bound nitrogen in the LP XM46 is converted to NOx, and less than 1% carbon is converted to CO.

Upadhye, R.S.; Watkins, B.E.

1994-04-01

381

Approach to improving PRA by identifying and quantifying errors of commission and dependency during LP S  

SciTech Connect

Human reliability analysis (HRA) is an integral part of probabilistic risk assessments (PRAs). Although various approaches and methods have been proposed since the first HRA was performed as part of the Reactor Safety Study (WASH-1400) almost two decades ago, the technology associated with HRA is still not fully developed. The limitations of the existing HRA approaches become particularly important when the role of the human is examined in the context of nuclear power plants (NPPS) during low-power and shutdown (LP S) conditions. Evaluations of events that have occurred during LP S have indicated that human activities and performance play a much larger role in shutdown than during full-power operations. During LP S conditions, the normal power operation configuration is altered substantially so that there is less automated control. As a result, control of the NPP unit is maintained almost entirely by human interaction. To properly account for the increase of human interactions in a PRA of LP S operations, it is necessary for an improved HRA methodology to be developed and integrated into the PRA process. In response to this need, an analysis of operational experience during LP S was performed to determine the critical factors that contribute to human performance, and a program plan for research was developed to improve existing HRA methodologies and provide a more realistic and justifiable model of human reliability for future PRAs.

Luckas, W.J.; Brown, W.S. (Brookhaven National Lab., Upton, NY (United States)); Wreathall, J. (John Wreathall and Co Inc., Dublin, OH (United States)); Cooper, S.E. (SAIC, Reston, VA (United States)); Bley, D.C. (PLG Inc., Newport Beach, CA (United States))

1993-01-01

382

EFFECTS OF SERIES AND SHUNT FACTS DEVICES IN TRANSIENT STABILITY ENHANCEMENT OF MULTI-MACHINE POWER SYSTEMS  

Microsoft Academic Search

In this paper a study is performed on Transient Stability enhancement in multi-machine power systems using Unified Power Flow Controller (UPFC). The paper uses the Injection Model of UPFC and series quadrature voltage injection and shunt compensation used for oscillation damping and then the effects of series and shunt compensation separately and together analyzed. Then different locations for UPFC in

S. Javad Sajjadi; M. Hasan Mohseninejad; Saeed Afsharnia

383

Method of removing the effects of electrical shorts and shunts created during the fabrication process of a solar cell  

DOEpatents

A method of removing the effects of electrical shorts and shunts created during the fabrication process and improving the performance of a solar cell with a thick film cermet electrode opposite to the incident surface by applying a reverse bias voltage of sufficient magnitude to burn out the electrical shorts and shunts but less than the break down voltage of the solar cell.

Nostrand, Gerald E. (Jamesburg, NJ); Hanak, Joseph J. (Lawrenceville, NJ)

1979-01-01

384

Pseudocysts of the Abdomen Associated with Ventriculoperitoneal Shunts: A Report of Twelve Cases and a Review of the Literature  

Microsoft Academic Search

Shunt complications are reported to occur at a rate of approximately 26%. One of the less frequent but important complications is that of the pseudocyst. Since Harsh’s first mention of a periumbilical cyst associated with a shunt in 1954, 44 cases have been reported in the literature. These are reviewed in addition to 12 cases of our own. From the

Sarah J. Gaskill; Arthur E. Marlin

1989-01-01

385

Subdural effusions re-appearing after shunts in patients with non-tumoural stenosis of the aqueduct.  

PubMed

Three patients shunted for non-tumoural stenosis of the aqueduct suffered from progressive clinical symptoms about four months after the shunting. Computed tomography (CT) showed bilateral subdural effusions. The effusions were evacuated, and the shunts revised. One month later all patients suffered from symptoms of increased intracranial pressure, and CT showed enlargement of the supratentorial cerebral ventricles. The effusions had disappeared. After shunt revision the symptoms decreased again. The fluctuation in the ventricular size, the thickness of the subdural effusions, and the clinical deterioration were related to the change in the opening pressure of the shunt valve in all patients. Patients with large supratentorial cerebral ventricles (Evans index over 0.40) should be monitored by intraventricular pressure recording in order to select the exact opening pressure of the shunt valve before inserting a relieving shunt; a clinical check-up and a CT examination should be carried out about three months after the operation in order to investigate any changes in the function of the shunt. PMID:6837342

Kuurne, T; Servo, A; Porras, M

1983-01-01

386

Broadband transmission noise reduction of smart panels featuring piezoelectric shunt circuits and sound-absorbing material  

NASA Astrophysics Data System (ADS)

The possibility of a broadband noise reduction of piezoelectric smart panels is experimentally studied. A piezoelectric smart panel is basically a plate structure on which piezoelectric patches with electrical shunt circuits are mounted and sound-absorbing material is bonded on the surface of the structure. Sound-absorbing material can absorb the sound transmitted at the midfrequency region effectively while the use of piezoelectric shunt damping can reduce the transmission at resonance frequencies of the panel structure. To be able to reduce the sound transmission at low panel resonance frequencies, piezoelectric damping using the measured electrical impedance model is adopted. A resonant shunt circuit for piezoelectric shunt damping is composed of resistor and inductor in series, and they are determined by maximizing the dissipated energy through the circuit. The transmitted noise-reduction performance of smart panels is tested in an acoustic tunnel. The tunnel is a square cross-sectional tube and a loudspeaker is mounted at one side of the tube as a sound source. Panels are mounted in the middle of the tunnel and the transmitted sound pressure across panels is measured. When an absorbing material is bonded on a single plate, a remarkable transmitted noise reduction in the midfrequency region is observed except for the fundamental resonance frequency of the plate. By enabling the piezoelectric shunt damping, noise reduction is achieved at the resonance frequency as well. Piezoelectric smart panels incorporating passive absorbing material and piezoelectric shunt damping is a promising technology for noise reduction over a broadband of frequencies. copyright 2002 Acoustical Society of America.

Kim, Jaehwan; Lee, Joong-Kuen

2002-09-01

387

Electrospun polyurethane as an alternative ventricular catheter and in vitro model of shunt obstruction.  

PubMed

Intracranial pressure and volume vary considerably between hydrocephalic patients, and with age, health and haemodynamic status; if left untreated, intracranial pressure rises and the ventricular system expands to accommodate the excess cerebrospinal fluid, with significant morbidity and mortality. Cerebrospinal fluid shunts in use today have a high incidence of failure with shunt obstruction being the most serious. Conventional proximal shunt catheters are made from poly(dimethyl)siloxane, the walls of which are perforated with holes for the cerebrospinal fluid to pass through. The limited range of catheters, in terms of material selection and flow distribution, is responsible in large part for their poor performance. In this study, we present an alternative design of proximal catheter made of electrospun polyether urethane, and evaluate its performance in the presence of glial cells, which are responsible for shunt blockage. The viability and growth of cells on catheter materials such as poly(dimethyl)siloxane and polyurethane in the form of cast films, microfibrous mats and porous sponges were studied in the presence of proteins present in cerebrospinal fluid after 48?h and 96?h in culture. The numbers of viable cells on each substrate were comparable to untreated poly(dimethyl)siloxane, both in the presence and absence of serum proteins found in cerebrospinal fluid. A cell culture model of shunt obstruction was developed in which cells on electrospun polyether urethane catheters were subjected to flow during culture in vitro, and the degree of obstruction quantified in terms of hydraulic permeability after static and perfusion culture. The results indicate that a catheter made of electrospun polyether urethane would be able to maintain cerebrospinal fluid flow even with the presence of cells for the time period chosen for this study. These findings have implications for the design and deployment of microporous shunt catheter systems for the treatment of hydrocephalus. PMID:25245779

Suresh, Supraja; Black, Richard A

2015-02-01

388

Electrospun polyurethane as an alternative ventricular catheter and in vitro model of shunt obstruction  

PubMed Central

Intracranial pressure and volume vary considerably between hydrocephalic patients, and with age, health and haemodynamic status; if left untreated, intracranial pressure rises and the ventricular system expands to accommodate the excess cerebrospinal fluid, with significant morbidity and mortality. Cerebrospinal fluid shunts in use today have a high incidence of failure with shunt obstruction being the most serious. Conventional proximal shunt catheters are made from poly(dimethyl)siloxane, the walls of which are perforated with holes for the cerebrospinal fluid to pass through. The limited range of catheters, in terms of material selection and flow distribution, is responsible in large part for their poor performance. In this study, we present an alternative design of proximal catheter made of electrospun polyether urethane, and evaluate its performance in the presence of glial cells, which are responsible for shunt blockage. The viability and growth of cells on catheter materials such as poly(dimethyl)siloxane and polyurethane in the form of cast films, microfibrous mats and porous sponges were studied in the presence of proteins present in cerebrospinal fluid after 48?h and 96?h in culture. The numbers of viable cells on each substrate were comparable to untreated poly(dimethyl)siloxane, both in the presence and absence of serum proteins found in cerebrospinal fluid. A cell culture model of shunt obstruction was developed in which cells on electrospun polyether urethane catheters were subjected to flow during culture in vitro, and the degree of obstruction quantified in terms of hydraulic permeability after static and perfusion culture. The results indicate that a catheter made of electrospun polyether urethane would be able to maintain cerebrospinal fluid flow even with the presence of cells for the time period chosen for this study. These findings have implications for the design and deployment of microporous shunt catheter systems for the treatment of hydrocephalus. PMID:25245779

Suresh, Supraja

2015-01-01

389

Denver peritoneovenous shunts for the management of malignant ascites: a review of the literature in the post LeVeen Era.  

PubMed

Most case series describing peritoneovenous (PV) shunts for malignant ascites include both LeVeen and Denver shunts. Conclusions based on these studies are no longer clinically relevant since the LeVeen shunt has been discontinued. The purpose of this study was to identify outcomes specific to Denver shunts to establish expected results in the modern era. Case series describing PV shunts for malignant ascites between 1980 and 2008 were identified through a keyword PUBMED search. Whenever possible, results attributable to Denver shunts were abstracted and analyzed. Nineteen series describing 341 patients undergoing 353 Denver PV shunts for malignant ascites were identified. The primary indications for PV shunts were unspecified or cancers of unknown origin (40%), ovarian cancer (16%), and pancreatic cancer (8%). Primary patency averaged 87 ± 57 days. Seventy-four per cent of patients died with functioning shunts. Complications occurred in 38% of patients including occlusion (24%) and disseminated intravascular coagulation (9%). Average survival of all patients was 3.0 ± 1.7 months and shunts provided effective palliation in 75.3%. One and a half per cent of 133 patients who had autopsies were reported to have hematologic dissemination. These results are not statistically different than overall results reported for both shunts combined or LeVeen shunts alone. Studies that report combined outcomes with Denver and LeVeen shunts for malignant ascites are neither negatively, nor positively influenced by one specific shunt. Expectations following PV shunting for malignant ascites do not have to be revised because LeVeen shunts are no longer available. PMID:21944526

White, Michael A; Agle, Steven C; Padia, Reema K; Zervos, Emmanuel E

2011-08-01

390

Investigation of the hydrodynamic properties of a new MRI-resistant programmable hydrocephalus shunt  

E-print Network

. Publish with BioMed Central and every scientist can read your work free of charge "BioMed Central will be the most significant development for disseminating the results of biomedical research in our lifetime." Sir Paul Nurse, Cancer Research UK Your... and shunt technology. A critical comparison of pro- grammable, hydrostatic and variable-resistance valves and flow-reducing devices. Childs Nerv Syst 1995, 11:193-202. 13. Baxter PS, MacKinnon AE: Overnight shunt pressure monitor- ing in children. Eur J...

Allin, David M; Czosnyka, Marek; Richards, Hugh K; Pickard, John D; Czosnyka, Zofia

2008-04-21

391

Increased serum immunoglobulin levels following portacaval shunt in the normal rat  

PubMed Central

Normal rats subjected to end-to-side portacaval shunt showed decreased survival and weight gain, a progressive fall in serum albumin and reciprocal rise in serum gamma globulin when compared with sham-operated controls for 12 weeks. Antibacterial lipopolysaccharide antibody was detected in significant titre at the sixth and twelfth weeks. It is suggested that the elevated levels of gamma globulin and reversal of albumin/globulin ratios noted in these animals may represent an immune response to bacterial lipopolysaccharides released into the systemic circulation as a result of the portacaval shunt. The hyperglobulinaemia of cirrhosis in human subjects may have a similar aetiology. PMID:4136811

Keraan, M.; Meyers, O. L.; Engelbrecht, G. H. C.; Hickman, Rosemary; Saunders, S. J.; Terblanche, John

1974-01-01

392

Graft-to-coronary-artery shunt during off-pump coronary artery bypass grafting.  

PubMed

We have developed a simple technique for temporary shunt from the saphenous vein graft to the coronary artery during off-pump coronary anastomosis. The ends of a 2-mm diameter tube were inserted into the distal end of the saphenous vein graft in which proximal anastomosis had been established and into the right coronary artery crux. Blood flow sufficient to maintain adequate hemodynamics was obtained through the shunt tube while suturing around the tube. We successfully employed this technique in 5 patients with acute coronary syndrome. We suggest that this technique may represent an addition to the armamentarium for off-pump anastomosis to the right coronary artery. PMID:16928480

Iida, Hiroshi; Mori, Hideaki; Sudo, Yoshio; Yamada, Yasuyuki; Eda, Kunihiro; Inoue, Yuho

2006-09-01

393

Pancreaticoportal Fistula and Disseminated Fat Necrosis After Revision of a Transjugular Intrahepatic Portosystemic Shunt  

SciTech Connect

A 59-year old man with alcohol related cirrhosis and portal hypertension was referred for transjugular intrahepatic portosystemic shunt (TIPS) to treat his refractory ascites. Ten years later, two sequential TIPS revisions were performed for shunt stenosis and recurrent ascites. After these revisions, he returned with increased serum pancreatic enzyme levels and disseminated superficial fat necrosis; an iatrogenic pancreaticoportal vein fistula caused by disruption of the pancreatic duct was suspected. The bare area of the TIPS was subsequently lined with a covered stent-graft, and serum enzyme levels returned to baseline. In the interval follow-up period, the patient has clinically improved.

Klein, Seth J., E-mail: kleins@mir.wustl.edu; Saad, Nael [Washington University School of Medicine, Interventional Radiology Section, Mallinckrodt Institute of Radiology (United States)] [Washington University School of Medicine, Interventional Radiology Section, Mallinckrodt Institute of Radiology (United States); Korenblat, Kevin [Washington University School of Medicine, Division of Gastroenterology, Department of Internal Medicine (United States)] [Washington University School of Medicine, Division of Gastroenterology, Department of Internal Medicine (United States); Darcy, Michael D. [Washington University School of Medicine, Interventional Radiology Section, Mallinckrodt Institute of Radiology (United States)] [Washington University School of Medicine, Interventional Radiology Section, Mallinckrodt Institute of Radiology (United States)

2013-04-15

394

Intracranial pressure parameters in idiopathic normal pressure hydrocephalus patients treated with ventriculo-peritoneal shunts  

Microsoft Academic Search

Summary  Background. Although the mean intracranial pressure (ICP) is normal in patients with idiopathic normal pressure hydrocephalus (iNPH),\\u000a there could possibly be alterations in their single ICP waves.\\u000a \\u000a Method. Thirty-nine consecutive patients treated for iNPH with ventriculo-peritoneal shunts were followed prospectively with regard\\u000a to clinical and radiological findings. Changes in clinical state 12 months after shunt surgery were assessed as change

P. K. Eide

2006-01-01

395

Incarceration of umbilical hernia after radiological insertion of a Denver peritoneovenous shunt.  

PubMed

We report a rare complication of incarceration of an umbilical hernia after Denver peritoneovenous shunt placement. A 50-year-old man presented with refractory ascites from liver cirrhosis. He also had an umbilical hernia. Because the ascites became uncontrollable, Denver peritoneovenous shunting was performed. The operation was successful and the ascites decreased. Ten days later, however, incarceration of the umbilical hernia occurred. A surgical repair was performed, but he died 2 days later. The cause of death was considered to be sepsis. PMID:23196823

Ohta, Kengo; Shimohira, Masashi; Hashizume, Takuya; Kawai, Tatsuya; Kurosaka, Kenichiro; Suzuki, Kazushi; Watanabe, Kenichi; Shibamoto, Yuta

2013-03-01

396

Unusual Ventriculoperitoneal (VP) Shunt Tube Extrusion through Anus in a Child with Dandy Walker Malformation: A Rare Case Report.  

PubMed

Aim of this paper is to report a case of extrusion of Ventriculo peritoneal shunt tube through anus in a one year female child ( k/c/o dandy walker malformation ) treated with placement of ventriculo peritoneal shunt for post operative hydrocephalus after excision of Subtorcular occipital meningocoel. The exact cause of such extrusion is not known. Unusual migration of distal catheter tip of VP shunt is a rare and bowel perforation is reported to occur between 0.1% and 0.7%. The possible factors responsible for this complication are thin bowel wall in children, sharp and stiff end of the VP shunt, use of trocar by some surgeons, chronic irritation by the shunt, previous surgery, infection and silicone allergy. In view of the potential for meningitis prompt and aggressive management is essential to avoid morbidity and mortality. PMID:25738035

Bansal, Hanish; Gupta, Gulzar; Gupta, Mayank; Kaushal, Rakesh

2015-01-01

397

Successful living donor liver transplant in a child with Abernethy malformation with biliary atresia, ventricular septal defect and intrapulmonary shunting.  

PubMed

Congenital portosystemic shunts are the anomalies in which the mesenteric venous drainage bypasses the liver and drains directly into the systemic circulation. This is a report of a rare case of LDLT in a four-yr old male child suffering with biliary atresia (post-failed Kasai procedure) associated with (i) a large congenital CEPSh from the spleno-mesentric confluence to the LHV, (ii) intrapulmonary shunts, (iii) perimembranous VSD. The left lobe graft was procured from the mother of the child. Recipient IVC and the shunt vessel were preserved during the hepatectomy, and the caval and shunt clamping were remarkably short while performing the HV and portal anastomosis. Post-operative course was uneventful; intrapulmonary shunts regressed within three months after transplantation and currently after 18 months following transplant child is doing well with normal liver functions. CEPSh has been extensively discussed and all the published cases of liver transplantation for CEPSh were reviewed. PMID:19254272

Singhal, Ashish; Srivastava, Ajitabh; Goyal, Neerav; Vij, Vivek; Wadhawan, Manav; Bera, Motilal; Gupta, Subash

2009-12-01

398

Capillary tone: cyclooxygenase, shear stress, luminal glycocalyx, and hydraulic conductivity (Lp).  

PubMed

Control of capillary hydraulic conductivity (Lp) is the physiological mechanism that underpins systemic hydration. Capillaries form the largest surface of endothelial cells in any species with a cardiovascular system and all capillaries are exposed to the flow-induced force, shear stress (?). Vasoactive molecules such as prostacyclin (cyclooxygenase product, COX) are released from endothelial cells in response to ?. Little is known about how COX activity impacts capillary Lp. The purpose here was to assess Lp in situ following an acute ?? stimulus and during COX1/COX2 inhibition. Mesenteric true capillaries (TC) of Rana pipiens (pithed) were cannulated for Lp assessment using the modified Landis technique. Rana were randomized into Control and Test groups. Two capillaries per animal were used (perfusate, 10 mg·mL(-1) BSA/frog Ringer's; superfusate, frog Ringer's or indomethacin (10(-5) mol·L(-1)) mixed in frog Ringer's solution). Three distinct responses of Lp to indomethacin (TC2) were demonstrated (TC1 and TC2 medians: Test Subgroup 1, 3.0 vs. 1.8; Test Subgroup 2, 18.2 vs. 2.2; Test Subgroup 3, 4.2 vs. 10.2 × 10(-7) cm·sec(-1)·cm H2O(-1)). Multiple regression analysis revealed a relationship between capillary Lp and systemic red blood cell concentration or hematocrit, plasma protein concentration, and ?? (Test Subgroup 1, R(2) = 0.59, P < 0.0001; Test Subgroup 2, R(2) = 0.96, P = 0.002), but only during COX inhibition. Maintaining red blood cell and plasma protein levels within a normal range may control barrier function in a healthy state. Recovering barrier function may be an unrecognized benefit of transfusions during blood loss or edema formation. PMID:25896981

Williams, Donna A; Flood, Mary H

2015-04-01

399

Enhanced Expression of Lp-PLA2 and Lysophosphatidylcholine in Symptomatic Carotid Atherosclerotic Plaques  

PubMed Central

Background and Purpose Circulating lipoprotein-associated phospholipase A2 (Lp-PLA2) has emerged as a novel biomarker for cardiovascular diseases. However, the correlation between the plaque expression of Lp-PLA2 and plaque oxidative stress, inflammation, and stability as well as the clinical presentation remains poorly defined, especially for cerebrovascular disease. Therefore, this study was performed to test the hypothesis that Lp-PLA2 expression is higher in symptomatic than in asymptomatic carotid plaques of patients undergoing carotid endarterectomy. Methods The expression of Lp-PLA2 in 167 carotid artery plaques was determined by immunoblotting and immunostaining. Plaque oxidative stress, inflammation, and stability were quantified by NAD(P)H oxidase p67phox and MMP-2 immunoblotting, oxidized LDL (oxLDL) immunoreactivity, macrophage and Sirius red collagen staining. Lysophosphatidylcholine 16:0 (lysoPC) concentration was measured in 55 plaques using liquid chromatography tandem mass spectrometry. Results Lp-PLA2 expression was significantly higher in plaques of symptomatic patients than asymptomatic patients (1.66±0.19 versus 1.14±0.10, P<0.05) and localized mainly to shoulder and necrotic lipid core areas in colocalization with oxLDL and macrophage content. Similarly, Lp-PLA2 expression was related to collagen content, which was lower in plaques from symptomatic patients than in plaques from asymptomatic patients (9.1±2.2 versus 18.5±1.7% of staining/field, P<0.001). LysoPC plaque concentration was significantly higher in plaques of symptomatic than asymptomatic patients (437.0±57.91 versus 228.84±37.00 mmol/L, P<0.05). Conclusions Symptomatic carotid artery plaques are characterized by increased levels of Lp-PLA2 and its product lysoPC in correlation with markers of tissue oxidative stress, inflammation, and instability. These findings strongly support a role for Lp-PLA2 in the pathophysiology and clinical presentation of cerebrovascular disease. PMID:18356547

Mannheim, Dallit; Herrmann, Joerg; Versari, Daniele; Gössl, Mario; Meyer, Fredric B.; McConnell, Joseph P.; Lerman, Lilach O.; Lerman, Amir

2015-01-01

400

LP-gas sales gain in estimated 4%; severe winter to boost 1977 sales  

Microsoft Academic Search

The National LP-Gas Association reports that sales of LP-gas rose 4.0% in 1976 to an estimated 15.81 billion gal. Residential and commercial sales accounted for 7.13 billion gal, a 1.6% increase; sales to the chemical industry 4.41 billion, 5.6% more; the engine-fuel market 1.17 billion, up 0.5%; and utility sales 0.45 billion, a 12.0% rise. Industrial sales declined 1.3% to

Hartzell

1977-01-01

401

Sparse-Representation-Based Direct Minimum Lp-Norm Algorithm for MRI Phase Unwrapping  

PubMed Central

A sparse-representation-based direct minimum Lp-norm algorithm is proposed for a two-dimensional MRI phase unwrapping. First, the algorithm converts the weighted-Lp-norm-minimization-based phase unwrapping problem into a linear system problem whose system (coefficient) matrix is a large, symmetric one. Then, the coefficient-matrix is represented in the sparse structure. Finally, standard direct solvers are employed to solve this linear system. Several wrapped phase datasets, including simulated and MR data, were used to evaluate this algorithm's performance. The results demonstrated that the proposed algorithm for unwrapping MRI phase data is reliable and robust. PMID:24790637

He, Wei; Liu, Feng

2014-01-01

402

75 FR 19644 - West Oaks Energy NY/NE, LP; Supplemental Notice That Initial Market-Based Rate Filing Includes...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Regulatory Commission [Docket No. ER10-1030-000] West Oaks Energy NY/NE, LP; Supplemental Notice That Initial Market-Based...supplemental notice in the above-referenced proceeding of West Oaks Energy NY/NE LP's application for market-based rate...

2010-04-15

403

78 FR 78353 - NuStar Crude Oil Pipeline L.P.; Notice of Petiton for Declaratory Order  

Federal Register 2010, 2011, 2012, 2013, 2014

...Docket No. OR14-12-000] NuStar Crude Oil Pipeline L.P.; Notice of Petiton...207(a)(2)(2013), NuStar Crude Oil Pipeline L.P. (NuStar) filed...expansion of NuStar's South Texas Crude Oil Pipeline system to transport...

2013-12-26

404

78 FR 4842 - Linden VFT, LLC v. Brookfield Energy Marketing, LP, Cargill Power Markets, LLC; Notice of Complaint  

Federal Register 2010, 2011, 2012, 2013, 2014

...Linden VFT, LLC v. Brookfield Energy Marketing, LP, Cargill Power Markets, LLC...formal complaint against Brookfield Energy Marketing, LP and Cargill Power Markets, LLC...DC 20426. This filing is accessible on-line at http://www.ferc.gov,...

2013-01-23

405

78 FR 10128 - Expansion/Reorganization of Foreign-Trade Subzone 70T; Marathon Petroleum Company LP; Detroit, MI  

Federal Register 2010, 2011, 2012, 2013, 2014

...Expansion/Reorganization of Foreign-Trade Subzone 70T; Marathon Petroleum Company LP; Detroit, MI Pursuant to its authority...Site 1 of Subzone 70T and remove Site 3 of the subzone at the Marathon Petroleum Company LP refinery in Detroit, Michigan....

2013-02-13

406

75 FR 17706 - Flint Hills Resources, LP, Complainant v. Mid-America Pipeline Company, LLC, Respondent; Notice...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Energy Regulatory Commission [Docket No. OR10-11-000] Flint Hills Resources, LP, Complainant v. Mid-America Pipeline...Commerce Act, 49 U.S.C. App. 2, 3, 13, and 15 (1988), Flint Hills Resources, LP (Complainant) filed a complaint...

2010-04-07

407

75 FR 56093 - Eagle Rock Desoto Pipeline, LP; Notice of Motion for Extension of Rate Case Filing Deadline  

Federal Register 2010, 2011, 2012, 2013, 2014

...Commission [Docket No. PR09-1-002] Eagle Rock Desoto Pipeline, LP; Notice of Motion for Extension...Take notice that on September 8, 2010, Eagle Rock Desoto Pipeline, L.P. (Eagle Rock) filed a request to extend the date for...

2010-09-15

408

SPECTRUM CLASSIFICATION FOR EARLY FAULT DIAGNOSIS OF THE LP GAS PRESSURE REGULATOR BASED ON THE KULLBACK-LEIBLER KERNEL  

E-print Network

SPECTRUM CLASSIFICATION FOR EARLY FAULT DIAGNOSIS OF THE LP GAS PRESSURE REGULATOR BASED The present paper describes a frequency spectrum classi- fication method for fault diagnosis of the LP gas, such as polyno- mial or Gaussian kernels, or the conventional fault diagnosis method and Gaussian Mixture Model

Higuchi, Tomoyuki

409

77 FR 24723 - AstraZeneca Pharmaceuticals LP; Withdrawal of Approval of a New Drug Application for IRESSA  

Federal Register 2010, 2011, 2012, 2013, 2014

...Administration [Docket No. FDA-2012-N-0370] AstraZeneca Pharmaceuticals LP; Withdrawal of Approval of a New Drug Application for...for IRESSA (gefitinib) Tablets held by AstraZeneca Pharmaceuticals LP (AstraZeneca), 1800 Concord Pike, P.O. Box...

2012-04-25

410

Transjugular Intrahepatic Portosystemic Shunt for the Treatment of Portal Hypertension in Noncirrhotic Patients with Portal Cavernoma  

PubMed Central

Background. The purpose of this study was to evaluate the safety and efficacy of transjugular intrahepatic portosystemic shunt (TIPS) placement in the management of portal hypertension in noncirrhotic patients with portal cavernoma. Methods. We conducted a single institution retrospective analysis of 15 noncirrhotic patients with portal cavernoma treated with TIPS placement. 15 patients (4 women and 11 men) were evaluated via the technical success of TIPS placement, procedural complications, and follow-up shunt patency. Results. TIPS placement was technically successful in 11 out of 15 patients (73.3%). Procedure-related complications were limited to a single instance of hepatic encephalopathy in one patient. In patients with successful shunt placement, the portal pressure gradient decreased from 25.8 ± 5.7 to 9.5 ± 4.2?mmHg (P < 0.001). TIPS dysfunction occurred in two patients during a median follow-up time of 45.2 months. Revision was not performed in one patient due to inadequate inflow. The other patient died of massive gastrointestinal bleeding in a local hospital. The remaining nine patients maintained functioning shunts through their last evaluation. Conclusions. TIPS is a safe and effective therapeutic treatment for noncirrhotic patients with symptomatic portal hypertension secondary to portal cavernoma. PMID:24868203

Luo, Xuefeng; Zhou, Biao; Yao, Denghua; Ma, Huaiyuan; Jiang, Mingshan; Zhang, Hailong; Li, Xiao

2014-01-01

411

Broadband transmission noise reduction of smart panels featuring piezoelectric shunt circuits and sound-absorbing material  

Microsoft Academic Search

The possibility of a broadband noise reduction of piezoelectric smart panels is experimentally studied. A piezoelectric smart panel is basically a plate structure on which piezoelectric patches with electrical shunt circuits are mounted and sound-absorbing material is bonded on the surface of the structure. Sound-absorbing material can absorb the sound transmitted at the midfrequency region effectively while the use of

Jaehwan Kim; Joong-Kuen Lee

2002-01-01

412

Experimental Percutaneous Extrahepatic Portacaval Shunt Creation by Transjugular Approach in Swine  

Microsoft Academic Search

The purpose of the study was to evaluate the feasibility of the creation of a percutaneous extrahepatic portacaval shunt (PEPS) in swine by a transjugular approach and to find a suitable stent-graft to use in PEPS. In 12 swine, the extrahepatic portal vein (PV) was entered from the inferior vena cava (IVC) by a needle system introduced from the transjugular

Chang Kyu Seong; Dusan Pavcnik; Barry T. Uchida; Hiroshi Anai; Hans Timmermans; Mahtab Niyyati; Christopher L. Corless; Luiz O. Correa; Frederick S. Keller; Josef Rösch

2005-01-01

413

Voltage compensation of an induction generator with long-shunt connection  

Microsoft Academic Search

Preliminary studies of voltage vs. speed relationships, stability of generated voltage, and voltage compensation of the self-excited induction generator are presented. In order to improve the voltage regulation, the long-shunt connection of the capacitors to the generator is used. The magnetizing inductance of the machine is used as a saturable reactor. The values of the capacitors for series and parallel

E. Bim; J. Szajner; Y. Burian

1989-01-01

414

Reduced Skin Capillary Density During Attacks of Erythromelalgia Implies Arteriovenous Shunting as Pathogenetic Mechanism  

Microsoft Academic Search

Erythromelalgia is characterized by burning pain, erythema, and increased temperature in acral skin. The pain is aggravated by warming and relieved by cooling. Increased microvascular arteriovenous shunting in deep dermal plexa has been hypothesized as the pathogenetic mechanism of pain in affected skin, inducing hypoxia during pain attacks. The aim of this study was to quantify skin capillary density in

Cato Mørk; Knut Kvernebo; Claes L. Asker; E. Goran Salerud

2002-01-01

415

Feasibility Study of Leakage Current Shunting Method Based on the Ladder Network Model  

Microsoft Academic Search

This paper investigates the nonuniformed distribution of leakage current in a wooden pole with the cross arm attached by using the network ladder model and evaluates the effectiveness of leakage current shunting arrangements that could minimize the occurrence of pole fire. The mitigation method that is proposed in this paper diverts excessive leakage current from a fire-prone hotspot along the

K. L. Wong; M. F. Rahmat

2010-01-01

416

Computer simulation of magnetization-controlled shunt reactors for calculating electromagnetic transients in power systems  

SciTech Connect

A computer procedure for simulating magnetization-controlled dc shunt reactors is described, which enables the electromagnetic transients in electric power systems to be calculated. It is shown that, by taking technically simple measures in the control system, one can obtain high-speed reactors sufficient for many purposes, and dispense with the use of high-power devices for compensating higher harmonic components.

Karpov, A. S. [St Petersburg State Polytechnical University, JSC 'System Operator of the United Power System', Leningradskoe RDU (Russian Federation)] [St Petersburg State Polytechnical University, JSC 'System Operator of the United Power System', Leningradskoe RDU (Russian Federation)

2013-01-15

417

Control orientated synthesis of high-performance piezoelectric shunt impedances for structural vibration control  

Microsoft Academic Search

Piezoelectric transducers are commonly used as strain actuators in the control of mechanical vibration. One control strategy, termed piezoelectric shunt damping, involves the connection of an electrical impedance to the terminals of a structurally bonded transducer. When subject to deflection, charge generated in the transducer flows through the external impedance developing a counteractive voltage across the terminals. Many passive, nonlinear,

Andrew J. Fleming; S. O. Reza Moheimani

2005-01-01

418

Passive Shunt Damping of a Piezoelectric Stack Nanopositioner Arnfinn Aas Eielsen and Andrew J. Fleming  

E-print Network

at the Laboratory for Dynamics and Control of Nanosystems. Andrew J. Fleming andrew.flemingPassive Shunt Damping of a Piezoelectric Stack Nanopositioner Arnfinn Aas Eielsen and Andrew J. Fleming Abstract-- The speed and accuracy of nanopositioning sys- tems is heavily influenced

Fleming, Andrew J.

419

The natural history of portal hypertension after transjugular intrahepatic portosystemic shunts  

Microsoft Academic Search

BACKGROUND & AIMS: The effects of transjugular intrahepatic portosystemic shunt (TIPS) on portal hemodynamics, esophageal and gastric varices, and hepatic function have not been fully defined. The aim of this study was to define prospectively the effects of TIPS on portal pressures and flow, variceal resolution, and hepatic function.METHODS: Pressure and flow measurements were made by angiography and Doppler sonography,

AJ Sanyal; AM Freedman; VA Luketic; PP Purdum; ML Shiffman; J DeMeo; PE Cole; J Tisnado

1997-01-01

420

Negative capacitance shunt damping system with optimized characteristics for use with piezoelectric transducers  

NASA Astrophysics Data System (ADS)

For ecologic sustainability and decreasing reserves of fossile energy sources, fuel efficiency is a major concern especially for passenger aircraft. Therefore, lightweight structures made from carbon fiber plastics offer great potential. But when used for panel-like structures, they have the disadvantage of lower damping and coincidence frequencies compared to conventional differential metal constructions. Both aspects lead to an increased vibration level and by this a higher noise radiation. Because of this, special noise and vibration treatment is needed to ensure passenger cabin comfort. Besides passive damping and active structural acoustic control (ASAC), piezoelectric shunt damping is investigated. Due to its broadband performance, the negative capacitance shunt can be used for multimode systems with varying eigenfrequencies. These shunts are usually built with operational amplifiers and passive components as resistors and capacitors. This setup is sufficient for laboratory tests at low excitation levels. In fact, it is not capable of accessing the full voltage amplitude of common piezoelectric transducers, because most operational amplifiers only deliver +/-15V maximum output voltage. Therefore an improved setup is presented in this paper, which addresses the specific voltage requirements of a common piezoelectric transducer to achieve best performance. It comprises a tailored power source and an appropriate concept for the negative capacitance shunt hardware. This new hardware only uses standard operational amplifiers together with a high voltage power amplifier to cover the whole operating range of a piezoelectric transducer. A demonstrator board is developed and experimentally investigated at a test structure. Finally, the results are compared to a conventional setup.

Pohl, Martin

2014-03-01

421

[Pulmonary arterial hypertension in congenital heart defects with shunt: a heterogeneous and complex constellation].  

PubMed

It will be explained how pulmonary vascular disease can develop in congenital heart defects with primary left-to-right shunt across the different ages and stages of development, with and without surgical, interventional or medical treatment. Furthermore it will be discussed, in which specific stages of pulmonary vascular disease "advanced therapy" can be used. PMID:23720181

Zimmermann, R; Schranz, D; Ewert, P; Kaemmerer, H

2013-06-01

422

Shunting versus Inactivation: Analysis of Presynaptic Inhibitory Mechanisms in Primary Afferents of the Crayfish  

Microsoft Academic Search

Primary afferent depolarizations (PADs) are associated with presynaptic inhibition in both vertebrates and invertebrates. In the present study, we have used both anatomical and electro- physiological techniques to analyze the relative importance of shunting mechanisms versus sodium channel inactivation in mediating the decrease of action potential amplitude, and thereby presynaptic inhibition. Experiments were performed in sensory afferents of a stretch

Daniel Cattaert; Abdeljabbar El Manira

1999-01-01

423

Analysis of shunt active power filters using PSCAD for parallel operation  

Microsoft Academic Search

The modularity of shunt active power filters (APF) is considered to be the most advantageous feature that allows parallel operation of a number of modules. From the viewpoint of reliability, flexibility, and efficiency, modular filtering approach is quite appropriate for high power applications. This configuration allows various control schemes to be employed, namely power and frequency splitting and capacity limitation

Tolga Sürgevil; Kadir Vardar; Eyüp Akpnar

2009-01-01

424

Use of Contegra conduit reinforced with Goretex as a modified left Blalock-Taussig shunt.  

PubMed

This is the first report of the construction of a modified Blalock-Taussig shunt using a Contegra conduit reinforced with Goretex in a 4-year-old boy. The patient had a complex cardiac history with a primary diagnosis of pulmonary atresia, hypoplastic right ventricle (RV) and RV-coronary artery fistula. PMID:20824594

Vohra, H A; Whistance, R; Gulati, A; Haw, M P

2010-09-01

425

Brucella melitensis infection of ventriculo-peritoneal shunt: A form of neurobrucellosis manifested as gastrointestinal symptoms.  

PubMed

A report of a 9 year-old child with Myelomeningocele who has a ventriculo-peritoneal (VP) shunt presented with gastrointestinal symptoms and peritonitis. The patient had no CNS symptoms but the cerebrospinal fluid was positive for Brucella melitensis. We discuss neurobrucellosis in children, its various presentations, complications and challenges in treatment, choice of antibiotics and duration. PMID:23999355

Al-Otaibi, Abdulnasir; Almuneef, Maha; Shaalan, Mohammad Al

2014-02-01

426

Decrease in shunt volume in patients with cryptogenic stroke and patent foramen ovale  

Microsoft Academic Search

BACKGROUND: In patients with patent foramen ovale (PFO) there is evidence supporting the hypothesis of a change in right-to-left shunt (RLS) over time. Proven, this could have implications for the care of patients with PFO and a history of stroke. The following study addressed this hypothesis in a cohort of patients with stroke and PFO. METHODS: The RLS volume assessed

Christian Tanislav; Manfred Kaps; Marek Jauss; Erwin Stolz; Wolfgang Pabst; Max Nedelmann; Mathias Grebe; Frank Reichenberger; Jens Allendoerfer

2010-01-01

427

Alzheimer's disease comorbidity in normal pressure hydrocephalus: prevalence and shunt response  

Microsoft Academic Search

The clinical impact of Alzheimer's disease pathology at biopsy was investigated in 56 cognitively impaired patients undergoing shunt surgery for idiopathic normal pressure hydrocephalus (NPH). Cognition was measured by means of the global deterioration scale (GDS), the mini mental status examination (MMSE) and a battery of six psychometric tests. Gait was assessed using objective measurements of velocity and the ambulatory

J Golomb; J Wisoff; D C Miller; I Boksay; A Kluger; H Weiner; J Salton; W Graves

2000-01-01

428

Outcome of shunt operation on urinary incontinence in normal pressure hydrocephalus predicted by lumbar puncture  

Microsoft Academic Search

Bladder function in four patients with normal pressure hydrocephalus, one with dementia of Alzheimer type and five patients with multi-infarct dementia was studied by history and urodynamic tests (cystometry and Bor's ice water test). The bladder hyperactivity could be temporarily improved by a lumbar puncture and removal of 50 ml CSF and later abolished by a shunt operation in patients

J Ahlberg; L Norlén; C Blomstrand; C Wikkelsö

1988-01-01

429

Cerebrospinal fluid markers before and after shunting in patients with secondary and idiopathic normal pressure hydrocephalus  

Microsoft Academic Search

BACKGROUND: The aim of this study was to explore biochemical changes in the cerebrospinal fluid (CSF) induced by shunt surgery and the relationship between these changes and clinical improvement. METHODS: We measured clinical symptoms and analysed lumbar CSF for protein content, neurodegeneration and neurotransmission markers in patients with secondary (SNPH, n = 17) and idiopathic NPH (INPH, n = 18)

Mats Tullberg; Kaj Blennow; Jan-Eric Månsson; Pam Fredman; Magnus Tisell; Carsten Wikkelsö

2008-01-01

430

A Multi-Mode Blade Damping Control using Shunted Piezoelectric Transducers with Active Feedback Structure  

NASA Technical Reports Server (NTRS)

The Structural Dynamics and. Mechanics branch (RXS) is developing smart adaptive structures to improve fan blade damping at resonances using piezoelectric (PE) transducers. In this presentation, only one shunted PE transducer was used to demonstrate active control of multi-mode blade resonance damping on a titanium alloy (Ti-6A1-4V) flat plate model, regardless of bending, torsion, and 2-stripe modes. This work would have a significant impact on the conventional passive shunt damping world because the standard feedback control design tools can now be used to design and implement electric shunt for vibration control. In other words, the passive shunt circuit components using massive inductors and. resistors for multi-mode resonance control can be replaced with digital codes. Furthermore, this active approach with multi patches can simultaneously control several modes in the engine operating range. Dr. Benjamin Choi presented the analytical and experimental results from this work at the Propulsion-Safety and. Affordable Readiness (P-SAR) Conference in March, 2009.

Choi, Benjamin; Morrison, Carlos; Min, James

2009-01-01

431

Optimization of a BT-Shunt Geometry for the Norwood Operation  

NASA Astrophysics Data System (ADS)

In this study, we present initial results of BT-shunt shape- parameterization and optimization using an automated approach that links optimization to a 3-D custom finite element flow solver. Shape optimization is performed using an efficient derivative-free optimization method called the surrogate management framework (SMF). Two objective functions are developed and tested: first to minimize energy-dissipation, and second to combine oxygen delivery and energy dissipation. Preliminary results suggest that a smooth bifurcation at the BA end with a shunt perpendicular to the PA is the best geometry to minimize energy dissipation, and that the inclusion of an oxygen delivery term in the objective function improved the ratio of systemic to pulmonary blood flow. To better account for global changes in the heart and circulatory system due to changes in shunt geometry, we have implemented a multiscale modeling approach that couples a 0-D lumped parameter network to the 3D flow solver. Initial results of this coupling using idealized geometries demonstrate its stability. Application to the BT shunt problem and design implications will be discussed.

Esmaily Moghadam, Mahdi; Feinstein, Jeffrey; Vignon-Clementel, Irene; Migliavacca, Francesco; Marsden, Alison

2010-11-01

432

Analytical solutions to a multicylinder somatic shunt cable model for passive neurones with spines.  

PubMed

A multicylinder somatic shunt model for spiny, passive neurones is considered. The spines are modelled as a continuum (after Baer & Rinzel, 1991), coupled through the spread of dendritic voltage. A general solution is developed and a relationship governing the contribution of dendrites, soma, and spines to the voltage response is derived. PMID:8522879

Kember, G C; Evans, J D

1995-06-01

433

Transjugular Intrahepatic Portosystemic Shunt Placement in Patients with Cirrhosis and Concomitant Portal Vein Thrombosis  

SciTech Connect

Purpose. To determine the safety and efficacy of transjugular intrahepatic portosystemic shunt (TIPS) creation in patients with liver cirrhosis complicated by thrombosed portal vein. Methods. This study reviewed 15 cases of TIPS creation in 15 cirrhotic patients with portal vein thrombosis at our institution over an 8-year period. There were 2 women and 13 men with a mean age of 53 years. Indications were refractory ascites, variceal hemorrhage, and refractory pleural effusion. Clinical follow-up was performed in all patients. Results. The technical success rate was 75% (3/4) in patients with chronic portal vein thrombosis associated with cavernomatous transformation and 91% (10/11) in patients with acute thrombosis or partial thrombosis, giving an overall success rate of 87%. Complications included postprocedural encephalopathy and localized hematoma at the access site. In patients with successful shunt placement, the total follow-up time was 223 months. The 30-day mortality rate was 13%. Two patients underwent liver transplantation at 35 days and 7 months, respectively, after TIPS insertion. One patient had an occluded shunt at 4 months with an unsuccessful revision. The remaining patients had functioning shunts at follow-up. Conclusion. TIPS creation in thrombosed portal vein is possible and might be a treatment option in certain patients.

Ha, Thuong G. Van, E-mail: tgvanha@radiology.bsd.uchicago.edu; Hodge, Justin; Funaki, Brian; Lorenz, Jonathan; Rosenblum, Jordan; Straus, Christopher; Leef, Jeff [University of Chicago, Department of Radiology, Section of Interventional Radiology (United States)

2006-10-15

434

Robust Passive Piezoelectric Shunt Dampener S. Behrens, A. J. Fleming and S. O. R. Moheimani  

E-print Network

structure is explained. For more details refer to.18 According to Ohm's law, v(s) = i(s)Z(s): (1 a piezoelectric transducer is attached to the surface of a exible structure using strong adhesive material) Furthermore, by writing Kirchho¤'s voltage law for the shunted transducer, as shown in Figure 1 (b), we obtain

Fleming, Andrew J.

435

Fibrous capsule formation of the peritoneal catheter tip in ventriculoperitoneal shunt: Two case reports  

PubMed Central

Background: A fibrous capsule formation of a peritoneal catheter tip has not previously been researched as a complication of ventriculoperitoneal (VP) shunts. Case Description: Two adult patients who had undergone a VP shunt for communicative hydrocephalus following subarachnoid hemorrhage caused by a ruptured aneurysm have been identified with malfunction of the VP shunt system by mild disturbance of consciousness and gait disturbance or loss of appetite. Hydrocephalus was diagnosed by computed tomography and the obstruction of the peritoneal catheter was revealed by shuntgraphy. Laparoscopy was performed and the peritoneal catheter tips were obstructed by fibrous white capsules that covered them. One was a thin membranous capsule like a stocking with two small endoluminal granulomas of the peritoneal catheter, and other one was a fibrous glossy white capsule like a sock. These fibrous capsules were excised by laparoscopy forceps without the conversion to a new peritoneal catheter. Following the procedure, the shunt functioned normally. The pathological diagnoses were peritoneum with foreign body reaction or hyalinization of membranous tissue surrounded by fibrous tissue. Conclusion: These fibrous capsules might be formed by the peritoneal reaction to cerebrospinal fluid as a foreign material. As such, a periodic medical check should be scheduled since a fibrous capsule of the peritoneal catheter tip might be formed again. PMID:25422787

Kano, Tomoaki

2014-01-01

436

Comparison of models for subtractive and shunting lateral-inhibition in receptor-neuron fields  

Microsoft Academic Search

Two types of neuronal lateral inhibition in one-dimensional fields of receptors and neurons are considered. The first type, which has been demonstrated in the eye of Limulus, is called subtractive inhibition (SI): it assumes that neuronal activity depends on the difference between the total excitation and inhibition. The second type is called shunting inhibition (SHI): it assumes that inhibitory influences

G. G. Furman; Murray Hi

1965-01-01

437

Successful repair of an atrial septal defect associated with right to left shunting  

Microsoft Academic Search

An atrial septal defect was successfully repaired in a young woman despite the presence of pulmonary hypertension and right to left shunting. Before repair both isoprenaline infusion and 100% inspired oxygen produced significant falls in pulmonary artery pressure and pulmonary vascular resistance. A lung biopsy specimen at operation indicated a considerable decrease in the concentration of parenchymal pulmonary arteries and

K F Hossack; J C Tewksbury; L M Reid

1989-01-01

438

Is Chryseobacterium indologenes a shunt-lover bacterium? A case report and review of the literature.  

PubMed

Chryseobacterium indologenes is a non-fermentative Gram-negative bacillus formerly belonging to the Flavobacterium genus. It is widely found in water and soil, also on wet surfaces of the hospital environment. It rarely causes infections and is usually associated with altered immune status or indwelling devices. We present a case of ventriculoperitoneal shunt infection caused by C. indologenes in a premature pediatric patient. A six-month-old male infant with congenital hydrocephalus and ventriculoperitoneal shunt was admitted with complaints of irritability, high fever and projectile vomiting. He was diagnosed as suffering from meningitis based on the clinical symptoms and laboratory findings of cerebrospinal fluid. The ventriculoperitoneal shunt was externalized and cerebrospinal fluid samples were sent for bacterial cultures. The isolated bacterium was identified as C. indologenes by conventional methods and the BD Phoenix™ 100 (Becton Dickinson, MD, USA) fully automated microbiology system. Antimicrobial susceptibility testing was performed by the microdilution method and Kirby-Bauer's disk diffusion method according to the Clinical and Laboratory Standards Institute guidelines. The isolate was found susceptible to ciprofloxacin, levofloxacin, cefoperazone and trimethoprim-sulfamethoxazole, while it was resistant to amikacin, aztreonam, cefepime, ceftazidime, gentamicin, imipenem and ticarcillin-clavulanic acid. The treatment was started with trimethoprim-sulfamethoxazole and cefoperazone-sulbactam The ventriculoperitoneal shunt was then removed. The patient was fully healed after two weeks and discharged. Central nervous system infection is a rare form of C. indologenes infections. The case presented herein may make a useful contribution to the existing literature. PMID:24335463

Ozcan, Nida; Dal, Tuba; Tekin, Alicem; Kelekci, Selvi; Can, Sukran; Ezin, Ozgur; Kandemir, Idris; Gul, Kadri

2013-12-01

439

Improved results with selective distal splenorenal shunt in a highly selected patient population. A prospective study.  

PubMed Central

In a 5-year period 299 patients were admitted to the Heinz-Kalk Hospital with bleeding esophageal varices. Patients with acute bleeding were treated with endoscopic sclerotherapy. Sessions were performed as many times as needed for each individual case. One hundred seventy-eight patients in Child-Pugh class C were excluded from surgical treatment; the remaining 121 patients (Child AB) were selected using the following criteria: liver volume (ultrasound) between 1000 to 2500 ml, portal perfusion (sequential scintigraphy) more than 30%, no activity or progression of liver disease proved by biopsy, no stenosis of the hepatic arteries, and suitable anatomy to perform the Warren shunt. Only 32 patients fulfilled these criteria. In seven of these cases the shunt was technically impossible to perform. Operative mortality rate was 8% and the late mortality rate was 12%. No history of rebleeding, encephalopathy, and/or shunt thrombosis was recorded. Five-year survival rate, according to the method of Kaplan-Meier was 75%. We conclude that the Warren shunt is the treatment of choice for elective management of bleeding esophageal varices. The postoperative results can be improved with strict selection using the above criteria. The preoperative use of sclerotherapy has a positive influence. Prophylactic management to prevent encephalopathy is also recommended. PMID:2787971

Paquet, K J; Mercado, M A; Koussouris, P; Kalk, J F; Siemens, F; Cuan-Orozco, F

1989-01-01

440

Communicated by Anthony Zador Shunting Inhibition Does Not Have a Divisive Effect on  

E-print Network

to the resting potential of the cell, has been shown to have a divi- sive effect on subthreshold excitatory potential to a value significantly above the resting potential, so that the current through the shunting the steady-state above-threshold membrane potential is computed as V = Isyn G , It has come to our attention

Koch, Christof

441

Sub-galeal coiling of the proximal and distal components of a ventriculo-peritoneal shunt. An unusual complication and proposed mechanism.  

PubMed

We describe the case of a child in whom proximal migration of the peritoneal catheter and extrusion of the ventricular catheter resulted in the entire ventriculo-peritoneal shunt along with the shunt chamber (Orbis Sigma II valve) lying in a sub-galeal pocket in the occipital region in a tightly coiled fashion. This coiling was very similar in appearance to that of the pre-insertion shunt in the packaging when it is supplied; hence it is postulated that the migration was secondary to retained 'memory' of the shunt tubing. This is a rare complication of ventriculo-peritoneal shunt, which has not been described before. PMID:11007499

Dominguez, C J; Tyagi, A; Hall, G; Timothy, J; Chumas, P D

2000-08-01

442

Piezoelectric Shunt Vibration Damping of F-15 Panel under High Acoustic Excitation  

NASA Technical Reports Server (NTRS)

At last year's SPIE symposium, we reported results of an experiment on structural vibration damping of an F-15 underbelly panel using piezoelectric shunting with five bonded PZT transducers. The panel vibration was induced with an acoustic speaker at an overall sound pressure level (OASPL) of about 90 dB. Amplitude reductions of 13.45 and 10.72 dB were achieved for the first and second modes, respectively, using single- and multiple-mode shunting. It is the purpose of this investigation to extend the passive piezoelectric shunt-damping technique to control structural vibration induced at higher acoustic excitation levels, and to examine the controllability and survivability of the bonded PZT transducers at these high levels. The shunting experiment was performed with the Thermal Acoustic Fatigue Apparatus (TAFA) at the NASA Langley Research Center using the same F-15 underbelly panel. The TAFA is a progressive wave tube facility. The panel was mounted in one wall of the TAFA test section using a specially designed mounting fixture such that the panel was subjected to grazing-incidence acoustic excitation. Five PZT transducers were used with two shunt circuits designed to control the first and second modes of the structure between 200 and 400 Hz. We first determined the values of the shunt inductance and resistance at an OASPL of 130 dB. These values were maintained while we gradually increased the OASPL from 130 to 154 dB in 6-dB steps. During each increment, the frequency response function between accelerometers on the panel and the acoustic excitation measured by microphones, before and after shunting, were recorded. Good response reduction was observed up to the 148dB level. The experiment was stopped at 154 dB due to wire breakage from vibration at a transducer wire joint. The PZT transducers, however, were still bonded well on the panel and survived at this high dB level. We also observed shifting of the frequency peaks toward lower frequency when the OASPL was increased. Detailed experimental results will be presented.

Wu, Shu-Yau; Turner, Travis L.; Rizzi, Stephen A.

2000-01-01

443

Risk factors for urolithiasis in dogs with congenital extrahepatic portosystemic shunts: 95 cases (1999-2013).  

PubMed

Objective-To identify risk factors for urolithiasis in dogs with congenital extrahepatic portosystemic shunts (EHPSSs) and to determine whether portoazygos shunts were associated with increased risk of urolithiasis at the initial evaluation for EHPSS. Design-Retrospective case series. Animals-Dogs (n = 95) with EHPSSs confirmed via CT angiography or surgery. Procedures-Medical records from 1999 to 2013 were reviewed. Variables of interest included signalment, previous medical management, and results of urinalysis, urolith analyses, and diagnostic imaging. Univariable and multivariable logistic regression analyses for assessment of risk factors for urolithiasis at the time of initial EHPSS evaluation were performed. Results-The dogs' median age was 0.9 years (range, 0.2 to 12.6 years). Among the 95 dogs, 27 (28.4%) and 68 (71.6%) had portoazygos and portocaval shunts, respectively. Urinalysis was performed for 79 (83.2%) dogs, 29 (36.7%) of which had crystalluria (mainly ammonium urate and struvite crystals). Uroliths were present in 34 of 95 (35.8%) dogs; 16 of 17 uroliths analyzed were composed of ammonium urate. Portoazygos shunts were not associated with significantly increased odds of urolithiasis at the time of the initial evaluation for EHPSS. However, the odds of urolithiasis was significantly increased for male dogs, older dogs, and dogs that received previous medical treatment. Conclusions and Clinical Relevance-In dogs with EHPSS, shunt morphology was not associated with increased odds of urolithiasis at the initial evaluation. Male dogs, older dogs, and dogs having received medical management for EHPSS prior to initial evaluation should be considered at increased risk for development of urolithiasis. PMID:25671285

G Caporali, Evelyn H; Phillips, Heidi; Underwood, Lucy; Selmic, Laura E

2015-03-01

444

Quantitative analysis of continuous intracranial pressure recordings in symptomatic patients with extracranial shunts  

PubMed Central

Objectives: To explore the outcome of management of possible shunt related symptoms using intracranial pressure (ICP) monitoring, and to identify potential methodological limitations with the current strategies of ICP assessment. Methods: The distribution of persistent symptoms related to extracranial shunt treatment was compared before and after management of shunt failure in 69 consecutive hydrocephalic cases. Management was heavily based on ICP monitoring (calculation of mean ICP and visual determination of plateau waves). After the end of patient management, all ICP curves were re-evaluated using a quantitative method and software (SensometricsTM pressure analyser). The ICP curves were presented as a matrix of numbers of ICP elevations (20 to 35 mm Hg) or depressions (-10 to -5 mm Hg) of different durations (0.5, 1, or 5 minutes). The numbers of ICP elevations/depressions standardised to 10 hours recording time were calculated to allow comparisons of ICP between individuals. Results: After ICP monitoring and management of the putative shunt related symptoms, the symptoms remained unchanged in as many as 58% of the cases, with the highest percentages in those patients with ICP considered normal or too low at the time of ICP monitoring. The quantitative analysis revealed a high frequency of ICP elevations (20 to 35 mm Hg lasting 0.5 to 1 minute) and ICP depressions (-10 to -5 mm Hg lasting 0.5, 1, or 5 minutes), particularly in patients with ICP considered normal. Conclusions: The value of continuous ICP monitoring with ICP analysis using current criteria appears doubtful in the management of possible shunt related symptoms. This may reflect limitations in the strategies of ICP analysis. Calculation of the exact numbers of ICP elevations and depressions may provide a more accurate description of the ICP profile. PMID:12531957

Eide, P

2003-01-01

445

Catheter-based interventions for modified blalock-taussig shunt obstruction: a 20-year experience.  

PubMed

Thrombotic occlusion of a modified Blalock-Taussig (BT) shunt is rare, leading to life-threatening hypoxemia. Rescue percutaneous interventions may allow recanalization of the systemic-to-pulmonary shunt but data on large patients' scales are lacking. We aimed to describe safety and effectiveness of catheter-based interventions to restore modified BT shunt patency. All patients who attempted transcatheter intervention for thrombotic occlusion of a modified BT shunt at our Institution from 1994 to 2014 were reviewed. Characteristics, management, and outcomes of the 28 identified patients were analyzed. Thirty-three procedures were performed at a median age of 0.6 years old (range 0.03-32.1 years) and a median weight of 5.8 kg (range 2.2-82 kg). Percutaneous intervention consisted in 33 balloon angioplasty (100 %) and 14 stent implantations (42.4 %). Thrombolytic agents were also used in 6.1 % cases. No peri-procedural death occurred but complications were observed in five patients (15.2 %), including one catheter-induced transient complete atrioventricular block, one cardiac tamponade, and one massive thrombo-embolic stroke. Early procedural success was obtained in 28 patients (84.8 %) and remained long-lasting in 26 patients (78.8 %). A young age and a low body-weight at the time of the procedure were significantly associated with procedural failure (p = 0.0364 and p = 0.0247, respectively). Although technically challenging and carrying potential major complications, transcatheter intervention can be considered as an efficient rescue strategy to restore patency in case of thrombotic obstruction of a modified BT shunt. PMID:25560736

Bonnet, Mathilde; Petit, Jérôme; Lambert, Virginie; Brenot, Philippe; Riou, Jean-Yves; Angel, Claude-Yves; Belli, Emre; Baruteau, Alban-Elouen

2015-04-01

446

Investigation of the hydrodynamic properties of a new MRI-resistant programmable hydrocephalus shunt  

PubMed Central

Background The Polaris valve is a newly released hydrocephalus shunt that is designed to drain cerebrospinal fluid (CSF) from the brain ventricles or lumbar CSF space. The aim of this study was to bench test the properties of the Polaris shunt, independently of the manufacturer. Methods The Polaris Valve is a ball-on-spring valve, which can be adjusted magnetically in vivo. A special mechanism is incorporated to prevent accidental re-adjustment by an external magnetic field. The performance and hydrodynamic properties of the valve were evaluated in the UK Shunt Evaluation Laboratory, Cambridge, UK. Results The three shunts tested showed good mechanical durability over the 3-month period of testing, and a stable hydrodynamic performance over 45 days. The pressure-flow performance curves, operating, opening and closing pressures were stable. The drainage rate of the shunt increased when a negative outlet pressure (siphoning) was applied. The hydrodynamic parameters fell within the limits specified by the manufacturer and changed according to the five programmed performance levels. Hydrodynamic resistance was dependant on operating pressure, changing from low values of 1.6 mmHg/ml/min at the lowest level to 11.2 mmHg/ml/min at the highest performance level. External programming proved to be easy and reliable. Even very strong magnetic fields (3 Tesla) were not able to change the programming of the valve. However, distortion of magnetic resonance images was present. Conclusion The Polaris Valve is a reliable, adjustable valve. Unlike other adjustable valves (except the Miethke ProGAV valve), the Polaris cannot be accidentally re-adjusted by an external magnetic field. PMID:18426562

Allin, David M; Czosnyka, Marek; Richards, Hugh K; Pickard, John D; Czosnyka, Zofia H

2008-01-01

447

Incidence of patent foramen ovale and migraine headache in adults with congenital heart disease with no known cardiac shunts.  

PubMed

The purpose of this study was to understand why patients with adult congenital heart disease (CHD) but no obvious shunt have an increased frequency of migraine headaches (MH). CHD patients with no known cardiac shunts (CHD-NKS), based on their echocardiographic or angiographic procedures, were tested for a right-to-left shunt using agitated saline contrast transcranial Doppler (TCD). Medical records of 2,920 patients from the UCLA Adult CHD Center were screened to participate in a study to evaluate the prevalence of MH in adults with CHD; 182 patients (6.23%) had CHD-NKS; of these, 60 (30%) underwent a TCD; 23 (38%) tested positive and 37 (62%) tested negative for a right-to-left shunt (P = 0.01 compared with controls). The frequency of MH was 43% in CHD-NKS compared with 11% in controls (P < 0.0001). TCD demonstrated right-to-left shunting in approximately 2/3 of patients with pulmonary stenosis, the Marfan syndrome and congenitally corrected transposition of great vessels, 1/4 of patients with bicuspid aortic valve, 1/5 of patients with mitral valve prolapse and all patients with Ebstein's anomaly. Approximately half of these experienced MH. Patients who had MH did not show a higher frequency of right-to-left shunt when compared with patients without MH (P = 0.57). In conclusion, CHD patients with conditions usually not associated with a shunt have a higher than expected prevalence of PFO which permits intermittent right-to-left shunting undetected by standard non-contrast TTE and TEE; the increased prevalence of right-to-left shunting may partially explain the higher than expected frequency of migraines. PMID:22927216

Volman, Marat; Mojadidi, M Khalid; Gevorgyan, Rubine; Kaing, Amy; Agrawal, Harsh; Tobis, Jonathan

2013-03-01

448

Experimental investigations in combining primal dual interior point method and simplex based LP solvers  

Microsoft Academic Search

The use of a primal dual interior point method (PD) based optimizer as a robust linear programming (LP) solver is now well established. Instead of replacing the sparse simplex algorithm (SSX), the PD is increasingly seen as complementing it. The progress of PD iterations is not hindered by the degeneracy or stalling problem of SSX, indeed it reaches the “near

Ron Levkovitz; Gautam Mitra

1995-01-01

449

Crater formation and sputtering by cluster impacts Z. Insepov a,*, L.P. Allen b  

E-print Network

Crater formation and sputtering by cluster impacts Z. Insepov a,*, L.P. Allen b , C. Santeufemio b coupling atomistic molecular dynamics simulations with continuum elasticity was used for studying craters by atomic force microscopy/transmission electron microscopy. They show that on a Si (1 0 0), craters

Florida, University of

450

76 FR 45247 - Tesoro Refining and Marketing Company v. SFPP, L.P.; Notice of Complaint  

Federal Register 2010, 2011, 2012, 2013, 2014

...OR 11-18-000] Tesoro Refining and Marketing Company v. SFPP, L.P.; Notice of...Policy Act of 1992. Tesoro Refining and Marketing Company (Complainant) filed a formal...DC 20426. This filing is accessible on-line at http://www.ferc.gov,...

2011-07-28

451

76 FR 49468 - Tesoro Refining and Marketing Company, SFPP, L.P.; Notice of Complaint  

Federal Register 2010, 2011, 2012, 2013, 2014

...OR11-20-000] Tesoro Refining and Marketing Company, SFPP, L.P.; Notice of...1992 (EPAct), Tesoro Refining and Marketing Company (Complainant) filed a complaint...DC 20426. This filing is accessible on-line at http://www.ferc.gov,...

2011-08-10

452

76 FR 45246 - Tesoro Refining and Marketing Company v. SFPP, L.P.; Notice of Complaint  

Federal Register 2010, 2011, 2012, 2013, 2014

...OR11-19-000] Tesoro Refining and Marketing Company v. SFPP, L.P.; Notice of...1992 (EPAct), Tesoro Refining and Marketing Company (Tesoro) filed a formal complaint...DC 20426. This filing is accessible on-line at http://www.ferc.gov,...

2011-07-28

453

76 FR 63918 - Tesoro Refining and Marketing Company v. SFPP, L.P.; Notice of Complaint  

Federal Register 2010, 2011, 2012, 2013, 2014

...OR12-3-000] Tesoro Refining and Marketing Company v. SFPP, L.P.; Notice of...App. 13(1), Tesoro Refining and Marketing Company (Complainant) filed a formal...DC 20426. This filing is accessible on-line at http://www.ferc.gov,...

2011-10-14

454

76 FR 25229 - Special Conditions: Gulfstream Aerospace LP (GALP) Model G250 Airplane, Dynamic Test Requirements...  

Federal Register 2010, 2011, 2012, 2013, 2014

These special conditions are issued for the Gulfstream Aerospace LP (GALP) model G250 airplane. This airplane will have a novel or unusual design feature associated with dynamic test requirements for side-facing, single-occupant seats. The applicable airworthiness regulations do not contain adequate or appropriate safety standards for this design feature. These special conditions contain the......

2011-05-04

455

Jordan Cove Energy Project Fort Chicago Energy Partners L.P.  

E-print Network

Jordan Cove Energy Project Fort Chicago Energy Partners L.P. 1.0 Bcfd Coos Bay, Oregon Oregon LNG Funding Partners 1.0-1.5 Bcfd Astoria, Oregon Portwestward LNG Facility Portwestward LNG, LLC 0.7-1.25 Bcfd Clatskanie, Oregon Kitimat LNG Facility Apache Corp 0.64 -1.0 Bcfd Kitimat, British Columbia

456

Optimizing planting areas using differential evolution (DE) and linear programming (LP)  

Microsoft Academic Search

3 is optimized to irrigate 2500 ha of land where 16 different crops are planted on different areas of land. The crops are assumed not rain-fed but depend only on irrigation water. The DE which is an evolutionary based optimization algorithm, with codes written in MATLAB is used to solve the problem. Also a comparative study using linear programming (LP)

Josiah Adeyemo; Fred Otieno

2009-01-01

457

Archiving David Edelberg’s Handel LP Collection: Production Workflow and Issues in Data Acquisition  

E-print Network

This paper describes the production workflow for building a digital archive of David Edelberg’s Handel LP collection and discusses the issues in phonograph data acquisition in general. Metadata elements from the metadata data dictionary for phonograph records are listed.

unknown authors

458

Archiving David Edelberg's Handel LP Collection: Production Workflow and Issues in Data Acquisition  

Microsoft Academic Search

This paper describes the production workflow for building a digital archive of David Edelberg's Handel LP collection and discusses the issues in phonograph data acquisition in general. Metadata elements from the metadata data dictionary for phonograph records are listed. Introduction Libraries worldwide are realizing the potential of digital information and initiating the digitization of their rare and unique cultural materials.

Catherine Lai; Ichiro Fujinaga

459

Boundedness and invertibility of multidimensional integral operators with anisotropically homogeneous kernels in weighted Lp-spaces  

NASA Astrophysics Data System (ADS)

In weighted space Lp (Rn,?), 1 < p < ?, a new broad class of integral operators with anisotropically homogeneous kernels is investigated. For such operators boundedness theorem is proved. Also the Banach algebra generated by operators with anisotropically homogeneous kernels of compact type is considered. For elements of the algebra symbolic calculation is constructed, the invertibility criterion is obtained in terms of operator symbol.

Elena, Miroshnikova

2014-12-01

460

What is a lumbar puncture? Lumbar puncture (LP), also called a spinal  

E-print Network

What is a lumbar puncture? Lumbar puncture (LP), also called a spinal tap, is the procedure doctors through) the bones of the spine until the spinal fluid is found. For testing, approxi- mately 2 to anticipate potential problems and minimize these risks. Lumbar Puncture Fact Sheet Memory & Aging Project

Baloh, Bob

461

LP-based solution methods for the asymmetric TSP Vardges Melkonian  

E-print Network

LP-based solution methods for the asymmetric TSP Vardges Melkonian Department of Mathematics, Ohio.[7]. Most of the research on TSP algorithms has concentrated on the undirected version of TSP in directed graphs to which we will refer as Asymmetric TSP (ATSP). The best approximation ratio of O(log n

Melkonian, Vardges

462

A Note on Dynamic Data Driven Wildfire Modeling , L.P. Franca1  

E-print Network

A Note on Dynamic Data Driven Wildfire Modeling J. Mandel1 , M. Chen1 , L.P. Franca1 , C. Johns1. A proposed system for real-time modeling of wildfires is described. The system involves numerical weather no capability to predict the spread of wildfires. In 2000 alone (the worst fire season in over 50 years), over

Douglas, Craig C.

463

78 FR 17194 - Gulf South Pipeline Company, LP; Notice of Application  

Federal Register 2010, 2011, 2012, 2013, 2014

...regarding this application should be directed to Michael E. McMahon or J. Kyle Stephens, Gulf South Pipeline Company, LP, 9 Greenway Plaza, Suite 2800, Houston, Texas 77046, or by calling (713) 479-8033 or Mike.McMahon@bwpmlp.com or...

2013-03-20

464

An LP-based algorithm for the data association problem in multitarget tracking  

Microsoft Academic Search

In this work we present a linear programming (LP) based approach for solving the data association problem (DAP) in multiple target tracking. It is well-known that the DAP can be formulated as an integer program. We present a compact formulation of the DAP. To solve practical instances of the DAP we propose an algorithm that uses an iterated K-scan sliding

Patrick P. A. Storms; Frits C. R. Spieksma

2003-01-01

465

77 FR 70812 - United States v. Star Atlantic Waste Holdings, L.P., Veolia Environnement S.A. and Veolia ES...  

Federal Register 2010, 2011, 2012, 2013, 2014

...JUSTICE Antitrust Division United States v. Star Atlantic Waste Holdings, L.P., Veolia...Columbia in United States of America v. Star Atlantic Waste Holdings, L.P., Veolia...alleging that the proposed acquisition by Star Atlantic Waste Holdings, L.P. of...

2012-11-27

466

Differential effects on portal and effective hepatic blood flow. A comparison between transjugular intrahepatic portasystemic shunt and small-diameter H-graft portacaval shunt.  

PubMed Central

OBJECTIVE: This study was undertaken to determine the effects of transjugular intrahepatic portasystemic shunt (TIPS) and small-diameter prosthetic H-graft portacaval shunt (HGPCS) on portal and effective hepatic blood flow. SUMMARY BACKGROUND DATA: Mortality after TIPS is higher than after HGPCS for bleeding varices. This higher mortality is because of hepatic failure, possibly a result of excessive diminution of hepatic blood flow. METHODS: Forty patients randomized prospectively to undergo TIPS or HGPCS had effective hepatic blood flow determined 1 day preshunt and 5 days postshunt using low-dose galactose clearance. Portal blood flow was determined using color-flow Doppler ultrasound. RESULTS: Treatment groups were similar in age, gender, and Child's class. Each procedure significantly reduced portal pressures and portasystemic pressure gradients. Portal flow after TIPS increased (21 mL/second +/- 11.9 to 31 mL/second +/- 16.9, p < 0.05), whereas it remained unchanged after HGPCS (26 mL/second +/- 27.7 to 14 mL/second +/- 41.1, p = n.s.). Effective hepatic blood flow was diminished significantly after TIPS (1684 mL/minute +/- 2161 to 676 mL/minute +/- 451, p < 0.05) and was unaffected by HGPCS (1901 mL/ minute +/- 1818 to 1662 mL/minute +/- 1035, p = n.s.). CONCLUSIONS: Both TIPS and HGPCS achieved significant reductions in portal vein pressure gradients. Portal flow increased after TIPS, although most portal flow was diverted through the shunt. Effective hepatic flow is reduced significantly after TIPS but well preserved after HGPCS. Hepatic decompensation and mortality after TIPS may be because, at least in part, of reductions in nutrient hepatic flow. PMID:9193187

Rosemurgy, A S; Zervos, E E; Goode, S E; Black, T J; Zwiebel, B R

1997-01-01

467

The CSF accumulator: its role in the central nervous system and implications for advancing hydrocephalus shunt technology.  

PubMed

The 'cerebrospinal fluid (CSF) accumulator' plays an important physiological role in the healthy central nervous system as both a shock absorber and regulator of drainage. In the presence of hydrocephalus, this function is compromised by resistance to the flow of CSF. It is further compromised by the placement of a standard shunt which allows only for one-way directional diversion of the fluid. Complications associated with shunt dependency may be a direct consequence of both the condition, and a failure of existing systems to restore the normal accumulator function. This article reviews the pathophysiology of the 'CSF accumulator' as it relates to hydrocephalus and its management, and proposes a biomimetic shunt designed to restore the 'CSF accumulator' toward normal. It is hoped that such a device will support normalization of intracranial pressure and restore an appropriate level of CSF volume in the shunted patient. PMID:9440493

Magram, G; Liakos, A M

1997-05-01

468

Active LQR and H2 shunt control of electromagnetic transducers. Andrew J. Fleming, Sam Behrens and S. O. Reza Moheimani  

E-print Network

Active LQR and H2 shunt control of electromagnetic transducers. Andrew J. Fleming, Sam Behrens of Newcastle, Callaghan 2308, Australia andrew@ee.newcastle.edu.au Abstract-- Electromagnetic transducers have

Fleming, Andrew J.

469

Exit ventriculoperitoneal shunt; enter endoscopic third ventriculostomy (ETV): contemporary views on hydrocephalus and their implications on management.  

PubMed

Hydrocephalus has been known to affect humans since the birth of human medicine as it is described by Hippocrates. The management of this condition is however still dodged by challenges due to a poor understanding of its pathophysiology. The ventriculoperitoneal shunt presents considerable problems especially with respect to infection and shunt malfunction. Low income countries, that currently face the greater burden of paediatric hydrocephalus. experience an increased challenge with ventriculoperitoneal shunts due to a shortage of qualified personnel to handle shunt complications. Recent advances in neuro-endoscopic surgery have presented opportunities for alternative treatment options for hydrocephalus such as endoscopic third ventriculostomy (ETV). This paper explores the alternative views in the pathophysiology of hydrocephalus and how they explain the effectiveness of ETV in treating hydrocephalus arising from a variety of causes. PMID:24358424

Kamalo, P

2013-09-01

470

Locally resonant band gaps achieved by equal frequency shunting circuits of piezoelectric rings in a periodic circular plate  

NASA Astrophysics Data System (ADS)

This work presents an investigation on vibration transmission in a circular thin plate consisting of metal rings and piezoelectric rings arrayed periodically. Each piezoelectric ring is linked to an independent resistive-inductive (RL) resonant shunting circuit. For a periodic rectangular piezoelectric plate, equal inductances are commonly used in resonant shunting circuits. However, for the circular one, the locally resonant (LR) band gap (BG) cannot be formed by shunting circuits with equal inductances, because different periodic cell has a different capacitance. Instead of equivalent inductance circuits, the equal frequency shunting circuits are employed to tune the resonance frequency of each circuit into the same, thus an integrating LR BG is obtained. A transfer matrix method is used to calculate transmission factor in the low frequency range. The theoretical model is verified by finite element method (FEM). The impact of geometric and circuit parameters on the properties of the LR BG and vibration attenuation band (VAB) has also been analyzed.

Dai, Longxiang; Jiang, Shan; Lian, Ziyang; Hu, Hongping; Chen, Xuedong

2015-02-01

471

Successful management with 2 overlapping bare stents for post-carotid endarterectomy carotid pseudoaneurysm secondary to carotid shunt.  

PubMed

Pseudoaneurysms are a rare complication of carotid endarterectomy. We successfully excluded with 2 overlapping bare stents a distal carotid artery pseudoaneurysm very likely induced by a Pruitt-Inahara shunt 2 months after carotid endarterectomy. PMID:25637577

Varetto, Gianfranco; Castagno, Claudio; Quaglino, Simone; Garneri, Paolo; Benintende, Emilio; Gibello, Lorenzo; Rossato, Denis; Rispoli, Pietro

2015-04-01

472

LP-search and its use in analysis of the accuracy of control systems with acoustical models  

NASA Technical Reports Server (NTRS)

The LP-search is proposed as an analog of the Monte Carlo method for finding values in nonlinear statistical systems. It is concluded that: To attain the required accuracy in solution to the problem of control for a statistical system in the LP-search, a considerably smaller number of tests is required than in the Monte Carlo method. The LP-search allows the possibility of multiple repetitions of tests under identical conditions and observability of the output variables of the system.

Sergeyev, V. I.; Sobol, I. M.; Statnikov, R. B.; Statnikov, I. N.

1973-01-01

473

A Selective Carotid Artery Shunting for Carotid Endarterectomy: Prospective MR DWI Monitoring of Embolization in a Group of 754 Patients.  

PubMed

Background?Intraoperative use of the intraluminal shunt may reduce the risk of a stroke by reducing cerebral blood flow compromise, but it may also increase the risk of atherosclerotic arterial wall damage with subsequent stroke during carotid endarterectomy (CEA). There is still no evidence to support routine or selective shunting. Material and Methods?A total of 754 CEAs were performed in a prospective study from 2005 to 2011 at our department. All procedures were done under regional anesthesia with selective carotid artery shunting according to neurologic status after internal carotid artery clamping. Magnetic resonance (MR) evaluation of brain parenchyma using diffusion-weighed imaging (DWI) sequence was performed upon hospital admission and 24 hours after the surgical procedure. Acute new MR DWI lesions were evaluated according to the classification published by Szabo et al. A routine neurologic evaluation was recorded as well. Results?The intraluminal shunt was used in 46 of 754 patients (6.1%). A new ischemic lesion was detected in 45 patients (6%). Most of these lesions were neurologically asymptomatic (80%). A new lesion on MR DWI in the subgroup of shunted patients was detected in 15 cases (32.6%) and in the subgroup of nonshunted patients in 30 cases (4.2%). Most of these lesions were due to embolization or hypoperfusion during shunt insertion. Conclusion?Use of the intraluminal shunt was the most important risk factor for the new MR DWI lesion in the entire group of CEAs. Results support the strategy of a selective use of intraluminal shunts. PMID:25539068

Orlický, Michal; Vachata, Petr; Bartoš, Robert; Waldauf, Petr; Sameš, Martin

2015-03-01

474

Cerebral Blood Flow Velocity and Vasomotor Reactivity Before and after Shunting Surgery in Patients with Normal Pressure Hydrocephalus  

Microsoft Academic Search

Summary  ?The purpose of this study was to evaluate pre- and post-shunting haemodynamic changes and their correlation with the clinical\\u000a results in normal pressure hydrocephalus (NPH). Accordingly, eleven demented patients with clinical signs suggestive of NPH\\u000a received examinations of cerebral blood flow velocity (BFV) and vasomotor reactivity (VMR) by transcranial Doppler sonography\\u000a with carbogen testing before and after shunt treatment. Computerized

E.-J. Lee; Y.-C. Hung; C.-H. Chang; M.-C. Pai; H.-H. Chen

1998-01-01

475

Complications of Ventriculo-Peritoneal Shunting and a Critical Comparison of the Three-Piece and One-Piece Systems  

Microsoft Academic Search

This is a report of our experience with ventriculo-peritoneal shunting, the treatment of congenital and secondary hydrocephalus. It includes a detailed listing of all complications and an analysis of the number of complications per patient and per procedure in patients in whom either a three-piece or a one-piece shunt system had been inserted. A total of 161 patients were in

Anthony J. Raimondi; J. Sam Robinson; Keiichi Kuwamura

1977-01-01

476

A prospective evaluation of changes in neuropsychological and liver function tests following transjugular intrahepatic portosystemic stent-shunt  

Microsoft Academic Search

Background\\/Aims: This study was designed to assess changes in: (a) neuropsychological tests, measures of memory, quality of life and scores for anxiety and depression; (b) liver function tests; and (c) the relationship between these following transjugular intrahepatic portosystemic stent-shunt.Methods: Twenty-nine patients undergoing transjugular intrahepatic portosystemic stent-shunt for recurrent variceal haemorrhage, 12 matched patients with cirrhosis and variceal haemorrhage manage with

Rajiv Jalan; Rebecca Gooday; Ronan E. O'Carroll; Doris N. Redhead; Robert A. Elton; Peter C. Hayes

1995-01-01

477

A power conditioning unit for high power GEO satellites based on the sequential switching shunt series regulator  

Microsoft Academic Search

This work describes the principles of the sequential switching shunt series regulator, S4R, an innovative solution proposed by the European Space Agency and other partners to power the next generation of high power telecommunications satellites. A comparative study between, the S4R regulated bus vs. the traditional option, the sequential switching shunt regulator regulated bus -S3R regulated bus- is performed to

Ausias Garrigós; José A. Carrasco; José M. Blanes; E. Sanchis-Kilders

2006-01-01

478

Preoperative trans-jugular porto-systemic shunt for oncological gastric surgery in a cirrhotic patient  

PubMed Central

Abdominal surgery in cirrhotic patients with portal hypertension is associated with high incidence of disease and mortality. In these patients, oncological gastric procedures with lymph-nodes dissection show much higher complication rates than in normotensive portal vein patients. Thus, normalization of portal vein pressure may be a favorable determinant factor to reduce complications. We report a case of a patient with hepatitis C virus-related hepatic cirrhosis, esophageal varices, portal hypertension and gastric cancer. We demonstrated the efficacy of a preoperative trans-jugular porto-systemic shunt to perform oncological radical resection more safely. We retained preoperative the trans-jugular porto-systemic shunt in the patients with elevated portal pressure and gastric cancer to perform a gastrectomy more safely and to decrease morbidity and mortality of these cases. PMID:25624736

Liverani, Andrea; Solinas, Luigi; Di Cesare, Tatiana; Velari, Luca; Neri, Tiziano; Cilurso, Francesco; Favi, Francesco; Bizzarri, Giancarlo

2015-01-01

479

Integration of Thermal Energy Harvesting in Semi-Active Piezoelectric Shunt-Damping Systems  

NASA Astrophysics Data System (ADS)

The opportunities to energize a broad range of devices by use of energy available almost anywhere and in many forms are almost unlimited. A major advantage of energy harvesting is the manufacture of small autonomous electronic devices with no need for power supply and maintenance. Shunt damping circuits, although unfavorably affected by the size and mass of bulky coil inductors, started to base on synthetic inductors losing their passivity. In this paper we report a study of the feasibility of powering shunt damping circuits by use of thermal energy otherwise irrevocably lost from a bearing. The heat generated in the bearing is converted thermoelectrically into electric energy which is then used to power synthetic inductance circuitry. We show that the power demand of such circuit can be satisfied by use of a thermoelectric generator paired with a moderately loaded bearing.

Lubieniecki, Micha?; Uhl, Tadeusz

2015-01-01

480

Comparison of Multiple Carrier Disposition PWM Techniques Applied for Multi-Level Shunt Active Filter  

NASA Astrophysics Data System (ADS)

This work presents the simulation of a shunt active filter using seven-level cascaded inverter. The ultimate objective is to bring out the influence of multiple carrier level shifted PWM techniques on the performance of a shunt active filter. Classical disposition PWM techniques such as PD, POD and APOD have been used to generate the gating signals for the inverter active switches. A comparison is presented to substantiate the effect of these techniques in filtering. The comparison is made from the perspective of reduction in THD of source currents after filtering. For compensation current extraction synchronous detection method has been used. The harmonic reduction is achieved in source currents as well as source voltages.

Kathalingam, Sebasthi Rani; Karantharaj, Porkumaran

2012-07-01

481

Intrapulmonary vascular shunt pathways in alveolar capillary dysplasia with misalignment of pulmonary veins.  

PubMed

Alveolar capillary dysplasia with misalignment of pulmonary veins (ACD/MPV) is a lethal neonatal lung disease characterised by severe pulmonary hypertension, abnormal vasculature and intractable hypoxaemia. Mechanisms linking abnormal lung vasculature with severe hypoxaemia in ACD/MPV are unknown. We investigated whether bronchopulmonary anastomoses form right-to-left shunt pathways in ACD/MVP. We studied 2 infants who died of ACD/MPV postmortem with direct injections of coloured ink into the pulmonary artery, bronchial artery and pulmonary veins. Extensive histological evaluations included serial sectioning, immunostaining and 3-dimensional reconstruction demonstrated striking intrapulmonary vascular pathways linking the systemic and pulmonary circulations that bypass the alveolar capillary bed. These data support the role of prominent right-to-left intrapulmonary vascular shunt pathways in the pathophysiology of ACD/MPV. PMID:25052575

Galambos, Csaba; Sims-Lucas, Sunder; Ali, Noorjahan; Gien, Jason; Dishop, Megan K; Abman, Steven H

2015-01-01

482

[Risk factors for ventricular peritoneal shunt infection in pediatric patients from the hospital Carlos Van Buren].  

PubMed

Hydrocephalus is a common problem in Neurosurgery and Neurology. The usual treatment is the installation of a Ventricular Peritoneal Shunt (VPS). Infection is the most frequent and serious complication. With the aim to identify risk factors associated with infection in the post surgery of VPS in pediatric patients from Carlos Van Buren Hospital a case control study between 1998-2008 was done. Cases were patients with VPS infection reported to the Department of Nosocomial Infections. Results in contingency tables were analyzed to determine Odds Ratio. 264 surgical procedures were studied in 207 patients with 53 infections reported in 26 patients. Significant risk factors were: history of prior ventriculitis, VPS dysfunction and prior external ventricular shunt, concurrent infections at the time of surgery and a neurosurgeon without the specialty of pediatric neurosurgery. We concluded that antibiotic prophylaxis was not an important factor in preventing infection and the neurosurgeon experience is relevant to the development of VPS infections. PMID:22552510

Pena A, Abigail; Sandia Z, Rodrigo; Riveros P, Rodrigo; Salazar Z, Cristian; Herrera O, Rosa; Vergara F, Rodrigo

2012-02-01

483

The Budd Chiari syndrome: a 22 year male treated successfully with mesocaval shunt.  

PubMed

Budd Chiari syndrome (BCS) is a heterogeneous group of disorders characterized by hepatic venous outflow obstruction at any level from the small hepatic veins to the atrio cava junction. BCS could have serious consequences if not treated promptly. Comprehensive angiographic studies, computerised tomography, liver ultrasonography, histology and pathologic analyses are essential for establishing the disease severity, stratifying risk factors, choosing the appropriate therapy and objectively assessing the response. The main objective of therapy is to alleviate portal and IVC hypertension. Here we present a report of a young man with BCS who underwent mesocaval shunt. The eight months follow up showed that patient was free of symptoms and duplex scans confirmed the patency of the shunt. PMID:25272556

Malik, Noureen; Bhatti, Ahsin Manzoor; Husssain, Syed Mukarram; Mansoor, Junaid; Saeed, Farrukh

2014-05-01

484

Thoraco-amniotic shunting for fetal pleural effusion--a case series.  

PubMed

Fetal pleural effusion is a rare occurrence, with an incidence of 1 per 10-15,000 pregnancies. The prognosis is related to the underlying cause and is often poor. There is increasing evidence that in utero therapy with thoraco-amniotic shunting improves prognosis by allowing lung expansion thereby preventing hydrops and pulmonary hypoplasia. This is a review of all cases of fetal pleural effusion managed over an eight year period the National Maternity Hospital Dublin. Over the nine year period there were 21 cases of fetal pleural effusion giving an overall incidence of 1 per 9281 deliveries. Of these, 15 underwent thoraco-amniotic shunting. There were associated anomalies diagnosed in 5 (33%) of cases. The overall survival in our cohort was 53%. The presence of hydrops was a poor prognostic factor, with survival in cases with hydrops of 33% (3/9) compared to 83% (5/6) in those cases without associated hydrops. PMID:21957687

Walsh, J; Mahony, R; Higgins, S; McParland, P; Carroll, S; McAuliffe, F

2011-01-01

485

On-line process analysis innovation: DiComp (tm) shunting dielectric sensor technology  

NASA Technical Reports Server (NTRS)

The DiComp Shunting Dielectric Sensor (SDS) is a new patent-pending technology developed under the Small Business Innovation Research Program (SBIR) for NASA's Kennedy Space Center. The incorporation of a shunt electrode into a conventional fringing field dielectric sensor makes the SDS uniquely sensitive to changes in material dielectric properties in the KHz to MHz range which were previously detectable only at GHz measurement frequencies. The initial NASA application of the SDS for Nutrient Delivery Control has demonstrated SDS capabilities for thickness and concentration measurement of Hoagland nutrient solutions. The commercial introduction of DiComp SDS technology for concentration and percent solids measurements in dispersions, emulsions and solutions represents a new technology for process measurements for liquids in a variety of industries.

Davis, Craig R.; Waldman, Frank A.

1993-01-01

486

Application of VSC-HVDC with Shunt Connected SMES for Compensation of Power Fluctuation  

NASA Astrophysics Data System (ADS)

This paper describes the application of VSC-HVDC (High Voltage DC Transmission using Voltage Source Converter) with shunt connected SMES (Superconducting Magnetic Energy Storage) for compensation of power fluctuation caused by fluctuating power source such as photovoltaics and wind turbines. The objectives of this proposed system is to smooth out fluctuating power in one terminal side of HVDC in order to avoid causing power system instability and frequency deviation by absorbing or providing power according to the system requirement while another terminal side power is fluctuated. The shunt connected SMES charges and discharges the energy to and from the dc side and it compensates required power of fluctuation to obtain constant power flow in one terminal side of VSC-HVDC system. This system configuration has ability for power system stabilization in the case of power fluctuation from natural energy source. PSCAD/EMTDC simulation is used to evaluate the performance of applied system configuration and control method.

Linn, Zarchi; Kakigano, Hiroaki; Miura, Yushi; Ise, Toshifumi

487

Rotational and magnetic shunt permanent magnet quadrupoles with variable magnetic strength  

SciTech Connect

Next Linear Collider (NLC) and Very Large Hadron Collider (VLHC) projects suppose to use permanent magnets as bending, focusing and correcting elements. Prototypes of two permanent magnet quadrupoles with variable strength were built and successfully tested in Fermilab. Quadrupoles have 12.7 mm aperture diameter, 100 T/m gradient with an adjustment range of 0 to -20%. Special designs provide high precision magnetic center stability during strength change. SmCo5 permanent magnet bricks were used in these prototypes. Rotational quadrupole consists of four sections. Two central sections are rotated in counter directions to adjust the strength. Magnetic shunt quadrupole design provides variable shunting of the magnetic flux. The numerical simulation, designs, measuring results are described.

Vladimir Kashikhin et al.

2002-03-28

488

Effect of zero-sequence compensated UHV balanced shunt reactor on secondary current and recovery voltage  

SciTech Connect

To reclose the transmission line successfully, the secondary arc, produced by the electromagnetic and electrostatic coupling between sound and faulted phases after the fault is cleared, must be extinguished promptly. Several methods have been proposed to reduce the secondary arc and recovery voltage. In the future UHV transmission line, the shunt reactors connected directly to the line play an important role. In this paper a method is discussed to suppress the secondary arc current and recovery voltage by the zero-sequence compensated-balanced shunt reactor. While the line analyzed so far is mainly the transposed single-circuit line, the untransposed double-circuit line is dealt with in this paper. The model system is a 1000 kV class UHV line.

Kurihara, I.; Sekine, Y.

1982-01-01

489

The power output and efficiency of a negative capacitance shunt for vibration control of a flexural system  

NASA Astrophysics Data System (ADS)

A negative capacitance shunt is a basic, analog, active circuit electrically connected to a piezoelectric transducer to control the vibrations of flexural bodies. The shunt circuit consists of a resistor and a synthetic negative capacitor to introduce a real and imaginary impedance on a vibrating mechanical system. The electrical impedance of the negative capacitance shunt modifies the effective modulus of the piezoelectric transducer to reduce the stiffness and increase the damping, which causes a decrease in amplitude of the vibrating structure to which the elements are bonded. To gain an insight into the electromechanical coupling and power output, the shunt and the electrical properties of the piezoelectric transducer are modeled using circuit modeling software. The power output of the model is validated with experimental measurements of a shunt connected to a piezoelectric transducer pair bonded to a vibrating aluminum cantilever beam. The model is used to select the passive components of the negative capacitance shunt to increase the efficiency and quantify the voltage output limit of the op-amp.

Beck, Benjamin S.; Cunefare, Kenneth A.; Collet, Manuel

2013-06-01

490

Programmable shunt valves: in vitro assessment of safety of the magnetic field generated by a portable game machine.  

PubMed

Cerebrospinal fluid (CSF) shunts are frequently used to treat hydrocephalus. The use of a programmable shunt valve allows physicians to easily change the opening pressure. Since patients with adjustable CSF shunt valves may use portable game machines, the permanent magnets in these machines may alter the shunt valve programmed settings or permanently damage the device. This study investigated the risk of unintentional valve adjustment associated with the use of game machines in patients with programmable CSF shunt valves. Four adjustable valves from 4 different manufacturers, Sophysa Polaris model SPV (Polaris valve), Miethke proGAV (proGAV), Codman Hakim programmable valve (CHPV), and Strata II small valve (Strata valve), were evaluated. Magnetic field interactions were determined using the portable game machine, Nintendo DS Lite (DS). The maximum distance between the valve and the DS that affected the valve pressure setting was measured by x-ray cinematography. The Polaris valve and proGAV were immune to unintentional reprogramming by the DS. However, the settings of the CHPV and Strata valves were randomly altered by the DS. Patients with an implanted shunt valve should be made aware of the risks posed by the magnetic fields associated with portable game machines and commonly used home electronics. PMID:21946726

Nakashima, Koji; Nakajo, Takato; Kawamo, Michiari; Kato, Akihito; Ishigaki, Seiichiro; Murakami, Hidetomo; Imaizumi, Yohichi; Izumiyama, Hitoshi

2011-01-01

491

Severe constipation: an under-appreciated cause of VP shunt malfunction: a case-based update  

Microsoft Academic Search

Background  Increased intra-abdominal pressure has been reported to result in raised intracranial pressure in a variety of conditions\\u000a such as obesity and pregnancy, and it also constitutes an infrequent cause of ventriculoperitoneal (VP) shunt malfunction.\\u000a Patients with neurological deficits, as those with myelomeningocele or cerebral palsy, are prone to developing a neurogenic\\u000a bowel and to suffer chronic constipation. Although previously recognized,

Juan F Martínez-Lage; José M Martos-Tello; Javier Ros-de-San Pedro; María José Almagro

2008-01-01

492

Effect of leakage current and shunt resistance on the light intensity dependence of organic solar cells  

NASA Astrophysics Data System (ADS)

In this report, we demonstrate that parasitic leakage currents dominate the current voltage characteristics of organic solar cells measured under illumination intensities less than one sun when the device shunt resistance is too low (<106 ? cm2). The implications of such effects on common interpretations of the light intensity dependence of the solar cell open circuit voltage, fill factor, short circuit current, and power conversion efficiency are discussed in detail.

Proctor, Christopher M.; Nguyen, Thuc-Quyen

2015-02-01

493

Current shunting and formation of stationary shock waves during electric explosions of metal wires in air  

SciTech Connect

Results of experiments on the generation of shock waves during electric explosions of fine copper and tungsten wires in air are analyzed. The generation mechanism of stationary shock wave by a plasma piston formed during the shunting breakdown of the electrode gap in the course of a wire explosion is investigated. The role of structural elements of such discharges, such as the core, corona, and wire environment, is analyzed.

Ivanenkov, G. V.; Gus'kov, S. Yu.; Barishpol'tsev, D. V. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)

2010-01-15

494

Combined Effects of Shunt and Luminescence Coupling on External Quantum Efficiency Measurements of Multijunction Solar Cells  

Microsoft Academic Search

The combined effects of shunt and luminescence coupling on the measurement artifact of external quantum efficiency (EQE) of multi-junction solar cells are studied. The EQE measurement artifact is modeled using DC and small-signal equivalent circuits under voltage and light bias conditions. The modeling results are verified with EQE measurements of a Ge bottom cell of a triple-junction solar cell. It

Jing-Jing Li; Swee Hoe Lim; Charles R. Allen; Ding Ding; Yong-Hang Zhang

2011-01-01

495

Zero rate of shunt infection in the first postoperative year in children – dream or reality?  

Microsoft Academic Search

The rate of infectious complications following shunt implantations at the Pierre Wertheimer Hospital was 6.4% in 1992–1994.\\u000a In order to improve this infection rate, new recommendations for surgery were applied and a new type of valve was used. The\\u000a effects of these measures after a 1-year follow-up were analyzed in 70 patients. The rate of infection was zero, 2.8, and

C. Mottolese; J. Grando; J. Convert; M. Abdoulrahman; H. Lelievre; F. Vandenesch; P. Bret; C. Lapras

2000-01-01

496

Shunting normal pressure hydrocephalus: the predictive value of combined clinical and CT data  

Microsoft Academic Search

The value of an ordinal global scale derived from combined clinical and CT data (clin\\/CT scale) to predict the clinical outcome in 112 patients shunted for presumed normal pressure hydrocephalus (NPH) was analysed. The clinical data were retrospectively collected, all CT scans were re-evaluated, and the clin\\/CT scale was determined blind to the results of further ancillary tests and to

J Vanneste; P Augustijn; W F Tan; C Dirven

1993-01-01

497

Resting pulmonary haemodynamics and shunting: a comparison of sea-level inhabitants to high altitude Sherpas  

PubMed Central

The incidence of blood flow through intracardiac shunt and intrapulmonary arteriovenous anastomoses (IPAVA) may differ between Sherpas permanently residing at high altitude (HA) and sea-level (SL) inhabitants as a result of evolutionary pressure to improve gas exchange and/or resting pulmonary haemodynamics. To test this hypothesis we compared sea-level inhabitants at SL (SL-SL; n = 17), during acute isocapnic hypoxia (SL-HX; n = 7) and following 3 weeks at 5050 m (SL-HA; n = 8 non-PFO subjects) to Sherpas at 5050 m (n = 14). , heart rate, pulmonary artery systolic pressure (PASP) and cardiac index (Qi) were measured during 5 min of room air breathing at SL and HA, during 20 min of isocapnic hypoxia (SL-HX; = 47 mmHg) and during 5 min of hyperoxia ( = 1.0; Sherpas only). Intracardiac shunt and IPAVA blood flow was evaluated by agitated saline contrast echocardiography. Although PASP was similar between groups at HA (Sherpas: 30.0 ± 6.0 mmHg; SL-HA: 32.7 ± 4.2 mmHg; P = 0.27), it was greater than SL-SL (19.4 ± 2.1 mmHg; P < 0.001). The proportion of subjects with intracardiac shunt was similar between groups (SL-SL: 41%; Sherpas: 50%). In the remaining subjects, IPAVA blood flow was found in 100% of subjects during acute isocapnic hypoxia at SL, but in only 4 of 7 Sherpas and 1 of 8 SL-HA subjects at rest. In conclusion, differences in resting pulmonary vascular regulation, intracardiac shunt and IPAVA blood flow do not appear to account for any adaptation to HA in Sherpa