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Sample records for access patency rates

  1. Vascular access for hemodialysis. Patency rates and results of revision.

    PubMed Central

    Palder, S B; Kirkman, R L; Whittemore, A D; Hakim, R M; Lazarus, J M; Tilney, N L

    1985-01-01

    Over a 4-year interval, 324 arteriovenous conduits were created in 256 patients with end-stage renal disease as access for chronic hemodialysis. These included 154 Cimino fistulae, 163 polytetrafluoroethylene (PTFE) grafts, and seven miscellaneous grafts. Satisfactory patency rates were demonstrated for as long as 4 years for both Cimino fistulae and PTFE grafts by life-table analysis. Failures of Cimino fistulae usually occurred early in the postoperative period, secondary to attempts to use inadequate veins. Thrombosis caused the majority of PTFE graft failures and was generally the result of venous stenosis. Correction of such venous stenosis is mandatory to restore graft patency and can result in prolonged graft survival. PMID:4015229

  2. Patency rate and complications of polytetrafluoroethylene grafts compared with polyurethane grafts for hemodialysis access

    PubMed Central

    2010-01-01

    Background The survival of hemodialysis patients requiring dialysis depends on the long-term functioning and patency of the vascular access. Prosthetic vascular grafts are inevitably used for patients whose vessels are unsuitable for an autogenous arteriovenous (AV) fistula. The purpose of this study was to compare the patency rate and associated complications using different types of grafts. Methods This prospective study was conducted on patients who did not have an appropriate vein for arteriovenous fistula from January 2004 through July 2006. They were divided into two groups, sex, age, and basic data matched. Polytetrafluoroethylene (PTFE) and polyurethane (PVAG) were the two types of grafts used in this study. The functionality of the graft was assessed immediately 1 day and 2 weeks after operation. The clinical follow-up was performed each 3 months until 24 months. Results One-year patency rate was reported to be 64% and 52% in the PTFE and PVAG groups, respectively. There was no significant difference in 1-year (64% versus 52%) and 2-year (49% versus 41%) patency rate of the PTFE and PVAG grafts used as vascular access. There was also no difference between the numbers of complications reported in the two groups. Conclusion It could be concluded that either PTFE or PVAG grafts can be used with the same expected outcomes. PMID:20218943

  3. Maintenance of permanent hemodialysis vascular access patency.

    PubMed

    Berkoben, M; Schwab, S J

    1995-02-01

    The morbidity and mortality of maintenance hemodialysis patients are in large part determined by the ability of the nephrologist, dialysis staff, and vascular surgeon to establish and maintain adequate vascular access. Primary arteriovenous fistulae are the preferred form of vascular access because they are the more likely to provide long-term complication-free access. In 1994, however, the majority of patients entering hemodialysis programs have vascular anatomy unsuitable for primary arteriovenous fistula creation. Synthetic fistulae are currently the more common form of vascular access. Unfortunately, this form of vascular access is more prone to thrombosis and infection. Thrombosis is the most common cause of vascular access loss. Venous stenoses account for the majority of thromboses but can be prospectively identified by performing routine measurements of venous dialysis pressure or urea recirculation. Prospective identification of venous stenoses followed by either angioplasty or surgical revision will improve fistula patency and enhance the quality of life of the hemodialysis population. PMID:7598559

  4. Impact of surgeon factor on radiocephalic fistula patency rates

    PubMed Central

    Arer, Ilker Murat; Yabanoglu, Hakan

    2015-01-01

    Introduction Hemodialysis with arteriovenous fistula (AVF) has been widely accepted treatment modality for patients with chronic renal failure (CRF). Radiocephalic fistulas are considered to be the most desirable for the initial vascular access. The aim of this study is to investigate the surgeon factor on radiocephalic fistula patency rates. Methods A total of 186 patients with diagnosis of CRF underwent Radiocephalic fistula for hemodialysis access were included. Patients were divided into 2 groups according to operating surgeon. Patients were evaluated according to demographic characteristics, secondary patency rates, second AVF creation and complications. Results Mean age was 57.7 ± 14.8 years. The most common etiology of CRF was idiopathic (66.6%). 40 (75.5%) patients in group 1 and 122 (91.7%) patients in group 2 were pre-dialysis patients (p < 0.05). Overall secondary patency rate was 77.4%. Patients in group 1 and group 2 have secondary patency rates of 83% and 75.2%, respectively (p = 0.458). Second AVF creation was done in 2 (3.8%) patients in group 1 and 23 (17.3%) patients in group 2 (p < 0.05). Postoperative complication rate was 9.6%. Conclusion Operating surgeon is not a major factor of secondary patency in radiocephalic arteriovenous fistulas. PMID:26900457

  5. How to prolong the patency of vascular access.

    PubMed

    Glazer, Sidney; Saint, Lindsey; Shenoy, Surendra

    2015-01-01

    Prolonging the patency and limiting the complications of a functioning hemodialysis (HD) access require a multidisciplinary approach. It begins with careful access planning that is executed and continually reinforced by physicians and facility staff encouraging active patient participation. Vascular access (VA) dysfunctions identified by regular monitoring and surveillance need further evaluation. Color duplex ultrasound is evolving as the primary tool to evaluate functional implication of the structural problems in the VA. While ease of scheduling makes endovascular management attractive, definitive surgical management provides better longevity and should be used when indicated. Timing of intervention and selection of technique depend on optimal use of available expertise and the nature of the problem. Avoiding a bridging HD catheter should be a priority while prolonging access patency and improving patient safety. PMID:25676299

  6. The Primary Patency of Percutaneous Transluminal Angioplasty in Hemodialysis Patients With Vascular Access Failure

    PubMed Central

    Kim, Woo Shin; Pyun, Wook Bum

    2011-01-01

    Background and Objectives Dysfunction of arteriovenous fistulas (AVFs) and arteriovenous grafts (AVGs) contributes significantly to morbidity and hospitalization in the dialysis population. We evaluated the primary patency of AVFs following percutaneous transluminal angioplasty (PTA) in haemodialysis patients. Subjects and Methods We performed 231 interventions in 118 patients with a mean age of 62.1±12.9 years. We performed 122 interventions in 53 AVG patients (44.9%), and 109 interventions in 65 AVF patients (55.1%). If there was thrombosis of the vascular access, urokinase was administered and/or thrombus aspiration was performed. The stent was inserted when balloon dilatation did not expand sufficiently or elastic recoil occurred. Results For the 118 patients, the median patency time was 10.45±10.29 months at 92 months of follow-up. The primary patencies for stenotic AVFs at 6, 12, 24, 36, 48, and 60 months were 63.4%, 41.4%, 17.0%, 9.7%, 7.3%, and 2.4%, respectively. The primary patencies for AVGs at 6, 12, 24, and 36 months were 36.9%, 19.5%, 10.8%, 2.1%, respectively, and were obtained by means of the Kaplan-Meier analysis (log rank=6.42, p<0.05). The median patency time was 11.0 months and 4.45 months in the non-thrombus and thrombus groups, respectively. The complication rate was 1.73% (4/231); two cases of pseudoaneurysms and two cases of extravasation were detected. All therapy failures (5/231) occurred in thrombotic lesions of AVGs and were treated surgically. Conclusion PTA is an efficacious method for the correction of stenosis of AVFs for hemodialysis, thus prolonging the patency of the fistulas. PMID:22022326

  7. Patency and Reintervention Rates During Routine TIPSS Surveillance

    SciTech Connect

    Latimer, Joanne; Bawa, Sadeeq M.; Rees, Colin J.; Hudson, Mark; Rose, John D.G.

    1998-05-15

    Purpose: To assess the medium-term outcome of transjugular intrahepatic portosystemic stent shunts (TIPSS) by measuring the incidence of shunt obstruction or failure during routine surveillance and the number of interventions performed. Methods: This is a retrospective study covering a 4-year period, from 1992 to 1996, during which 102 TIPSS procedures were performed. Indications for treatment were variceal bleeding (76%) and refractory ascites (24%). Follow-up protocol after TIPSS included transfemoral or transjugular portal venography and measurement of portosystemic pressure gradient (PPG) at 3 months, 12 months, and then at yearly intervals. The results of the first 155 venograms on 62 patients (mean follow-up 14 months) have been reviewed and Kaplan-Meier analysis performed. Results: One hundred and thirty-seven of 155 (88%) examinations showed patent shunts. Fifty-six of 137 (41%) of the patent TIPSS had elevated PPG with signs of stenosis. The majority (41/56) of shunt stenoses with elevated pressure gradients were related to neointimal hyperplasia in the hepatic venous aspect of the shunt. Interventions used to reduce the pressure gradient or to restore patency included: angioplasty (62/102 interventions), additional stents (21/102), a second TIPSS procedure (2/102), and thrombolysis or thrombectomy (4/102). The primary patency rate was 66% at 1 year (52% at 2 years). Primary assisted patency was 72% at 1 year (58% at 2 years). Secondary patency was 86% at 1 year (63% at 2 years). Conclusion: The majority of TIPSS shunts will remain patent when regular portal venography, with appropriate intervention, is undertaken. Although there is a high reintervention rate this mainly takes the form of balloon angioplasty.

  8. Novel no touch technique of saphenous vein harvesting: Is great graft patency rate provided?

    PubMed Central

    Papakonstantinou, Nikolaos A.; Baikoussis, Nikolaos G.; Goudevenos, John; Papadopoulos, George; Apostolakis, Efstratios

    2016-01-01

    Coronary artery bypass grafting surgery effectively relieves signs and symptoms of myocardial ischemia. The left internal thoracic artery (LITA) graft is the gold standard having 90–95% patency rate at 10 years, whereas only 50% of saphenous vein (SV) grafts are patent at 10 years. However, there is a novel “no touch” technique in order to harvest an SV complete with its cushion of surrounding tissue, thus maintaining its endothelium-intact. Significantly superior short- and long-term graft patency rates comparable to LITA grafts can be achieved. Consequently, the SV may be revived as an important conduit in coronary artery bypass surgery. PMID:27397453

  9. Surgical infrainguinal revascularization for peripheral arterial disease: factors affecting patency rate

    PubMed Central

    Jafarian, Ali; Elyasinia, Fezzeh; Keramati, Mohammad Reza; Ahmadi, Farham; Parsaei, Reza

    2015-01-01

    Background: Peripheral arterial disease is a source of morbidity and mortality. Surgical vascular reconstruction is a treatment option but probability of failure and complications are important concerns. In this study, we evaluated outcome of surgical infrainguinal reconstruction and factors affecting graft patency for a period of one year. Methods: In this cohort study, 85 consecutive patients with chronic ischemia who underwent lower extremity surgical vascular reconstruction (including 52 femoropopliteal and 25 femorofemoral bypass) from March 2007 to Feb 2009 were recruited. Graft patency was evaluated before discharge from hospital and one year after the surgical operation using duplex ultrasonography. Association between possible risk factors and graft patency were evaluated. Results: In general, 71% (37 patients) of femoropopliteal and 52% (13 patients) of femorofemoral reconstructions were patent during the follow up period. Diabetes mellitus, hypertension, smoking, opium use and ischemic heart disease were significantly associated with decreased rate of patency (p<0.05). Conclusion: Assessing risk factors that predict perioperative mortality and graft patency is essential for selecting patients that would benefit from surgery. Omitting surgical reconstruction and endovascular intervention may be preferable especially when multiple risk factors are present or in the absence of critical limb ischemia. PMID:26793669

  10. MRI Assessment of Uterine Artery Patency and Fibroid Infarction Rates 6 Months after Uterine Artery Embolization with Nonspherical Polyvinyl Alcohol

    SciTech Connect

    Das, Raj Gonsalves, Michael; Vlahos, Ioannis; Manyonda, Issac; Belli, Anna-Maria

    2013-10-15

    Purpose: We have observed significant rates of uterine artery patency after uterine artery embolization (UAE) with nonspherical polyvinyl alcohol (nsPVA) on 6 month follow-up MR scanning. The study aim was to quantitatively assess uterine artery patency after UAE with nsPVA and to assess the effect of continued uterine artery patency on outcomes. Methods: A single centre, retrospective study of 50 patients undergoing bilateral UAE for uterine leiomyomata was undertaken. Pelvic MRI was performed before and 6 months after UAE. All embolizations were performed with nsPVA. Outcome measures included uterine artery patency, uterine and dominant fibroid volume, dominant fibroid percentage infarction, presence of ovarian arterial collaterals, and symptom scores assessed by the Uterine Fibroid Symptom and Quality of Life questionnaire (UFS-QOL). Results: Magnetic resonance angiographic evidence of uterine artery recanalization was demonstrated in 90 % of the patients (64 % bilateral, 26 % unilateral) at 6 months. Eighty percent of all dominant fibroids demonstrated >90 % infarction. The mean percentage reduction in dominant fibroid volume was 35 %. No significant difference was identified between nonpatent, unilateral, and bilateral recanalization of the uterine arteries with regard to percentage dominant fibroid infarction or dominant fibroid volume reduction. The presence of bilaterally or unilaterally patent uterine arteries was not associated with inferior clinical outcomes (symptom score or UFS-QOL scores) at 6 months. Conclusion: The high rates of uterine artery patency challenge the current paradigm that nsPVA is a permanent embolic agent and that permanent uterine artery occlusion is necessary to optimally treat uterine fibroids. Despite high rates of uterine artery recanalization in this cohort, satisfactory fibroid infarction rates and UFS-QOL scores were achieved.

  11. Patency and Complications of Translumbar Dialysis Catheters.

    PubMed

    Liu, Fanna; Bennett, Stacy; Arrigain, Susana; Schold, Jesse; Heyka, Robert; McLennan, Gordon; Navaneethan, Sankar D

    2015-01-01

    Translumbar tunneled dialysis catheter (TLDC) is a temporary dialysis access for patients exhausted traditional access for dialysis. While few small studies reported successes with TLDC, additional studies are warranted to understand the short- and long-term patency and safety of TLDC. We conducted a retrospective analysis of adult patients who received TLDC for hemodialysis access from June 2006 to June 2013. Patient demographics, comorbid conditions, dialysis details, catheter insertion procedures and associated complications, catheter patency, and patient survival data were collected. Catheter patency was studied using Kaplan-Meier curve; catheter functionality was assessed with catheter intervals and catheter-related complications were used to estimate catheter safety. There were 84 TLDCs inserted in 28 patients with 28 primary insertions and 56 exchanges. All TLDC insertions were technically successful with good blood flow during dialysis (>300 ml/minute) and no immediate complications (major bleeding or clotting) were noted. The median number of days in place for initial catheter, secondary catheter, and total catheter were 65, 84, and 244 respectively. The catheter patency rate at 3, 6, and 12 months were 43%, 25%, and 7% respectively. The main complications were poor blood flow (40%) and catheter-related infection (36%), which led to 30.8% and 35.9% catheter removal, respectively. After translumbar catheter, 42.8% of the patients were successfully converted to another vascular access or peritoneal dialysis. This study data suggest that TLDC might serve as a safe, alternate access for dialysis patients in short-term who have exhausted conventional vascular access. PMID:25800550

  12. The Effect of Lowering LDL Cholesterol on Vascular Access Patency: Post Hoc Analysis of the Study of Heart and Renal Protection

    PubMed Central

    Herrington, William; Emberson, Jonathan; Staplin, Natalie; Blackwell, Lisa; Fellström, Bengt; Walker, Robert; Levin, Adeera; Hooi, Lai Seong; Massy, Ziad A.; Tesar, Vladimir; Reith, Christina; Haynes, Richard; Baigent, Colin

    2014-01-01

    Background and objectives Reducing LDL cholesterol (LDL-C) with statin-based therapy reduces the risk of major atherosclerotic events among patients with CKD, including dialysis patients, but the effect of lowering LDL-C on vascular access patency is unclear. Design, setting, participants, & measurements The Study of Heart and Renal Protection (SHARP) randomized patients with CKD to 20 mg simvastatin plus 10 mg ezetimibe daily versus matching placebo. This study aimed to explore the effects of treatment on vascular access occlusive events, defined as any access revision procedure, access thrombosis, removal of an old dialysis access, or formation of new permanent dialysis access. Results Among 2353 SHARP participants who had functioning vascular access at randomization, allocation to simvastatin plus ezetimibe resulted in a 13% proportional reduction in vascular access occlusive events (355 [29.7%] for simvastatin/ezetimibe versus 388 [33.5%] for placebo; risk ratio [RR], 0.87; 95% confidence interval [95% CI], 0.75 to 1.00; P=0.05). There was no evidence that the effects of treatment differed for any of the separate components of this outcome. To test the hypothesis raised by SHARP, comparable analyses were performed using the AURORA (A Study to Evaluate the Use of Rosuvastatin in Subjects on Regular Hemodialysis: An Assessment of Survival and Cardiovascular Events) trial cohort. AURORA did not provide independent confirmation (vascular access occlusive events: 352 [28.9%] for rosuvastatin versus 337 [27.6%] for placebo; RR, 1.06, 95% CI, 0.91 to 1.23; P=0.44). After combining the two trials, the overall effect of reducing LDL-C with a statin-based regimen on vascular access occlusive events was not statistically significant (707 [29.3%] with any LDL-C–lowering therapy versus 725 [30.5%] with placebo; RR, 0.95, 95% CI, 0.85 to 1.05; P=0.29). Conclusions Exploratory analyses from SHARP suggest that lowering LDL-C with statin-based therapy may improve vascular

  13. Complication Rates and Patency of Radiologically Guided Mushroom Gastrostomy, Balloon Gastrostomy, and Gastrojejunostomy: A Review of 250 Procedures

    SciTech Connect

    Yip, Doris; Vanasco, Matthew; Funaki, Brian

    2004-01-15

    To compare complication rates and tube performance of percutaneous mushroom gastrostomy, balloon gastrostomy, and gastrojejunostomy. Between September 9, 1999 and April 23, 2001, 203 patients underwent 250 radiologically guided percutaneous gastrostomy and gastrojejunostomy procedures. Follow-up was conducted through chart reviews and review of our interventional radiology database. Procedural and catheter-related complications were recorded. Chi-square statistical analysis was performed. In patients receiving mushroom-retained gastrostomy catheters (n = 114), the major complication rate was 0.88% (n = 1), the minor complication rate was 5.3% (n = 6), and the tube complication rate was 4.4% (n = 5). In patients receiving balloon-retained gastrostomy tubes (n = 67), the major complication rate was 0, the minor complication rate was 4.5% (n = 3), and the tube complication rate was 34.3% (n = 23). In patients receiving gastrojejunostomy catheters (n = 69), the major complication rate was 1.4% (n = 1), the minor complication rate was 2.9% (n = 2), and the tube complication rate was 34.8% (n = 24). No statistically significant differences were found between procedural or peri-procedural complications among the different types of tubes. Mushroom-retained catheters had significantly fewer tube complications (p < 0.01). Percutaneous gastrostomy and gastrojejunostomy have similar procedural and peri-procedural complication rates. Mushroom gastrostomy catheters have fewer tube-related complications compared with balloon gastrostomy and gastrojejunostomy catheters. In addition, mushroom-retained catheters exhibit the best overall long-term tube patency and are therefore the gastrostomy catheter of choice.

  14. Rate of fibrinogen breakdown related to coronary patency and bleeding complications in patients with thrombolysis in acute myocardial infarction--results from the PRIMI trial.

    PubMed

    Ostermann, H; Schmitz-Huebner, U; Windeler, J; Bär, F; Meyer, J; van de Loo, J

    1992-09-01

    Four hundred and one patients with acute myocardial infarction of less than 4 h duration were randomized to receive intravenous thrombolytic treatment with either 80 mg of full length unglycosylated single-chain-urokinase plasminogen activator (INN saruplase) or 1.5 million IU of streptokinase delivered over a 60 min period. Angiographic patency rates were higher at 60 min in saruplase treated patients (71.8% vs 48%; P less than 0.001), but did not differ significantly at 90 min (71.2% vs 63.9%; P = 0.15). Fibrinogen levels dropped markedly in both groups, the decrease being delayed and less pronounced with saruplase. Total fibrin and fibrinogen degradation products and D-dimer values rose earlier and to higher peak values in streptokinase treated patients. In both groups marked plasminogen and alpha 2-antiplasmin consumption was observed. Lower fibrinogen levels, and in particular the faster rate of fibrinogen breakdown, were associated with higher patency rates at 90 min (P less than 0.05). Patients with bleeding complications had lower 'lowest points' and a more rapid decrease in fibrinogen (P less than 0.05). These findings were not related to the drug used. Increased heparin levels at 6 to 12 h were correlated to bleeding complications in streptokinase treated patients. It is concluded that the rate of fibrinogen breakdown during and following thrombolytic treatment for acute myocardial infarction is related to early vessel patency and bleeding complications. PMID:1396833

  15. Graft modification strategies to improve patency of prosthetic arteriovenous grafts for hemodialysis.

    PubMed

    Moufarrej, Andrew; Tordoir, Jan; Mees, Barend

    2016-03-01

    Prosthetic arteriovenous grafts (AVGs) are indicated for vascular access for long-term hemodialysis in patients in whom creation or maintenance of an arteriovenous fistula (AVF) has failed or is contraindicated. AVGs have an inferior long-term patency as compared to AVFs. To ameliorate patency rates of prosthetic AVGs, different strategies have emerged to improve graft materials. This review aims to describe current strategies and future perspectives on graft modification, by graft geometry, drug coatings and graft surface technology, to improve AVG patency. PMID:26951913

  16. Cutting Balloon Angioplasty Versus Standard Balloon Angioplasty for Failing Infra-inguinal Vein Grafts: Comparative Study of Short- and Mid-Term Primary Patency Rates

    SciTech Connect

    Vikram, Raghunandan; Ross, Rose A.; Bhat, Rajesh; Griffiths, Gareth D.; Stonebridge, Peter A.; Houston, J. Graeme; Chakraverty, S.

    2007-07-15

    Purpose. To evaluate the results of a recent change in practice in our institution using cutting balloon angioplasty instead of standard balloon angioplasty as the primary treatment for failing infra-inguinal vein bypass grafts. Methods. In this nonrandomized cohort study with a historical control, failing infra-inguinal vein grafts were identified at duplex surveillance or clinical examination. Patients had confirmatory arteriography and balloon angioplasty at the same attendance. Interventions proximal or distal to the graft itself and prosthetic grafts were not included. Patients were entered into a duplex graft surveillance program. Initial assessment of technical success was duplex or improvement 4-6 weeks after the primary angioplasty. Results. Twenty-seven consecutive patients were treated with standard balloon angioplasty, then 11 consecutive patients were treated with cutting balloon angioplasty. Initial technical success was 74% for the standard balloon versus 82% for the cutting balloon. The primary patency rate at 6 months was 16/26 (62%) for standard balloon angioplasty and 8/10 (80%) for cutting balloon angioplasty (p = 0.44). The primary patency rate at 12 months was 9/25 (36%) for standard balloon angioplasty and 5/10 (50%) for cutting balloon angioplasty (p = 0.47). Conclusion. The use of cutting balloons for primary angioplasty of infra-inguinal vein grafts offers no definite advantage over standard balloon angioplasty in this institution or compared with patency rates after standard balloon angioplasty reported elsewhere. Larger multicenter studies would be required to demonstrate whether there was any real difference between the two techniques.

  17. Patency of Femoral Tunneled Hemodialysis Catheters and Factors Predictive of Patency Failure

    SciTech Connect

    Burton, Kirsteen R.; Guo, Lancia L. Q.; Tan, Kong T.; Simons, Martin E.; Sniderman, Kenneth W.; Kachura, John R.; Beecroft, John R.; Rajan, Dheeraj K.

    2012-12-15

    Purpose: To determine the patency rates of and factors associated with increased risk of patency failure in patients with femoral vein tunneled hemodialysis catheters. Methods: All femoral tunneled catheter insertions from 1996 to 2006 were reviewed, during which time 123 catheters were inserted. Of these, 66 were exchanges. Patients with femoral catheter failure versus those with femoral catheter patency were compared. Confounding factors, such as demographic and procedural factors, were incorporated and assessed using univariate and multivariable Cox proportional hazards regression analyses. Results: Mean catheter primary patency failure time was 96.3 days (SE 17.9 days). Primary patency at 30, 60, 90, and 180 days was 53.8%, 45.4%, 32.1%, and 27.1% respectively. Crude rates of risk of catheter failure did not suggest a benefit for patients receiving catheters introduced from one side versus the other, but more cephalad location of catheter tip was associated with improved patency. Multivariate analysis showed that patients whose catheters were on the left side (p = 0.009), were of increasing age at the time of insertion (p = 0.002) and that those who had diabetes (p = 0.001) were at significantly greater risk of catheter failure. The catheter infection rate was 1.4/1000 catheter days. Conclusion: Patients who were of a more advanced age and had diabetes were at greater risk of femoral catheter failure, whereas those who received femoral catheters from the right side were less at risk of catheter failure.

  18. Reducing haemodialysis access infection rates.

    PubMed

    Dorman, Amanda; Dainton, Marissa

    Infections are the second most common cause of vascular access loss in the long-term haemodialysis patient, and recent years have seen an increase in healthcare-associated infections (HCAIs) associated with vascular access (Suhail, 2009). There have been a number of drivers including publication guidelines (Department of Health, 2006; 2007) and local protocols providing evidence-based recommendations that, when implemented, can reduce the risk of these infections. In England, the selection of bloodstream infections caused by methicillin resistant staphylococcus aureus (MRSA) as a significant clinical outcome has led to a vast amount of work in this area. Root cause analysis of individual infections (by the clinical teams when these occur) in many specialities identified areas where practice could be improved, including practice relating to vascular access within the renal setting. Manufacturers have also supported this work by focusing on developing products that are designed to reduce the likelihood of infections occurring. One product identified and used within the NHS is Chloraprep. PMID:21646994

  19. Radial access during percutaneous interventions in patients with acute coronary syndromes: should we routinely monitor radial artery patency by ultrasonography promptly after the procedure and in long-term observation?

    PubMed

    Lisowska, Anna; Knapp, Małgorzata; Tycińska, Agnieszka; Sielatycki, Piotr; Sawicki, Robert; Kralisz, Paweł; Musiał, Włodzimierz J

    2015-01-01

    Access-site vascular complications in patients undergoing transradial coronary procedures are rare but may have relevant clinical consequences. The aim of the study was to evaluate: (1) radial artery's (RA) patency immediately after the procedure and in long-term observation, (2) factors influencing the frequency of radial artery's occlusion (RAO) after percutaneous coronary intervention (PCI) procedures performed via transradial access in the group of 220 patients with acute coronary syndromes (ACS). RA ultrasound was performed 48-72 h after the procedure and in those who were diagnosed with RAO-again after 6-12 months. According to the ultrasonographic findings, the patients were divided into two sub-groups: 187 pts (85 %) with patent RA after PCI and 33 pts (15 %) with RAO. Both sub-groups significantly statistically differed with regard to the frequency of local hematomas-15 versus 27.3 % (p = 0.02), the frequency of applying IIbIIIa inhibitors in PCI-6.4 versus 15.1 % (p = 0.015) and procedure duration-0.59 ± 0.37 versus 0.77 ± 0.38 (p = 0.014), respectively. In a multifactorial analysis the only factor influencing RA patency promptly after the procedure was PCI duration (p < 0.05, r = -0.22). In the follow-up, right RA remained still obstructed in 28 patients (12.7 %) whereas in five patients (2.3 %) the regular flow in RA was resumed. The chronic RAO was clinically silent. Due to insignificant frequency of the occurrence of RAO after PCI procedure in patients with ACS as well as practically lack of clinical consequences of this artery's occlusion in long-term observation, we do not see any implications to routine ultrasound periprocedural RA evaluation. PMID:25142060

  20. Endovascular Stent Placement for Hemodialysis Arteriovenous Access Stenosis.

    PubMed

    Neuen, Brendon L; Baer, Richard A; Grainer, Frank; Mantha, Murty L

    2015-01-01

    This study aims to report the outcomes of nitinol and polytetrafluoroethylene covered stent placement to treat hemodialysis arteriovenous access stenosis at a single center over a five-year period. Clinical and radiological information was reviewed retrospectively. Poststent primary and secondary patency rates were determined using Kaplan-Meier analysis. Ten clinical variables were subjected to multivariate Cox regression analysis to determine predictors of patency after stent placement. During the study period 60 stents were deployed in 45 patients, with a mean follow-up of 24.5 months. The clinical and anatomical success rate was 98.3% (59/60). Poststent primary patency rates at 6, 12, and 24 months were 64%, 46%, and 35%, respectively. Poststent secondary patency rates at 6, 12, and 24 months were 95%, 89%, and 85%, respectively. Stent placement for upper arm lesions and in access less than 12 months of age was associated with reduced primary patency (adjusted hazards ratio [HR] 5.1, p = 0.0084, and HR 3.5, p = 0.0029, resp.). Resistant or recurrent stenosis can be successfully treated by endovascular stent placement with durable long-term patency, although multiple procedures are often required. Stent placement for upper arm lesions and in arteriovenous access less than 12 months of age was associated with increased risk of patency loss. PMID:26649199

  1. Endovascular Stent Placement for Hemodialysis Arteriovenous Access Stenosis

    PubMed Central

    Neuen, Brendon L.; Baer, Richard A.; Grainer, Frank; Mantha, Murty L.

    2015-01-01

    This study aims to report the outcomes of nitinol and polytetrafluoroethylene covered stent placement to treat hemodialysis arteriovenous access stenosis at a single center over a five-year period. Clinical and radiological information was reviewed retrospectively. Poststent primary and secondary patency rates were determined using Kaplan-Meier analysis. Ten clinical variables were subjected to multivariate Cox regression analysis to determine predictors of patency after stent placement. During the study period 60 stents were deployed in 45 patients, with a mean follow-up of 24.5 months. The clinical and anatomical success rate was 98.3% (59/60). Poststent primary patency rates at 6, 12, and 24 months were 64%, 46%, and 35%, respectively. Poststent secondary patency rates at 6, 12, and 24 months were 95%, 89%, and 85%, respectively. Stent placement for upper arm lesions and in access less than 12 months of age was associated with reduced primary patency (adjusted hazards ratio [HR] 5.1, p = 0.0084, and HR 3.5, p = 0.0029, resp.). Resistant or recurrent stenosis can be successfully treated by endovascular stent placement with durable long-term patency, although multiple procedures are often required. Stent placement for upper arm lesions and in arteriovenous access less than 12 months of age was associated with increased risk of patency loss. PMID:26649199

  2. 47 CFR 76.970 - Commercial leased access rates.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 4 2011-10-01 2011-10-01 false Commercial leased access rates. 76.970 Section... MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Cable Rate Regulation § 76.970 Commercial leased access rates... determining whether an entity is an “affiliate” for purposes of commercial leased access, entities...

  3. Midterm Outcome of Femoral Artery Stenting and Factors Affecting Patency

    PubMed Central

    Yu, Jae Seoung; Park, Keun-Myoung; Jeon, Yong Sun; Cho, Soon Gu; Hong, Kee Chun; Shin, Woo Young; Choe, Yun-Mee; Shin, Seok-Hwan; Kim, Kyung Rae

    2015-01-01

    Purpose: The purpose of this study was to evaluate the early and midterm results of superficial femoral artery (SFA) stenting with self-expanding nitinol stents and to identify the factors affecting patency. Materials and Methods: SFA stenting was performed in 165 limbs of 117 patients from January 2009 to December 2013. Patients were followed-up for the first occurrence of occlusion or stenosis based on computed tomography and duplex scan results and a decrease in ankle brachial index of >15%. Results: During the follow-up period (mean, 15.3±3.2 months), no early thrombotic reocclusions occurred within 30 days, but in-stent restenosis developed in 78 limbs. The primary patency rates at 6, 12, 18, and 24 months were 78%, 66%, 42%, and 22%, respectively, and the secondary patency rates were 85%, 72%, 58%, and 58%, respectively. TASC II C or D lesions, stent length >8 cm, number of patent tibial arteries and diabetes were significantly associated with reintervention. Conclusion: The midterm results of stenting for SFA occlusive disease were disappointing because the primary and secondary patency rates at two years were 22% and 58%, respectively. Reintervention after SFA stenting remains a major problem, particularly in patients with diabetes mellitus or long TASC II C or D lesions. PMID:26719837

  4. Resistance within hemodialysis shunts predicts patency.

    PubMed

    Bui, Trung D; Gordon, Ian L; Parashar, Amish; Vo, David; Wilson, Samuel E

    2006-01-01

    The authors examined the relationship between patency after thrombectomy of clotted dialysis grafts and intraoperative measurements of flow (Q), pressure gradient (PGR), and longitudinal resistance (RL). Eighteen thrombosed arteriovenous (AV) grafts underwent 21 thrombectomies. Pressures at arterial (P1) and venous (P2) ends of the AV grafts were determined with 22-gauge catheters and standard transducers; flow was measured with transit-time probes; arithmetic averaging of waveforms was used to compute mean Q, PGR, and RL. Kaplan-Meier patency curves were analyzed by using log rank methods. Mean patency for all grafts was 164 +/-152 days. For each variable, the 21 measurements were split and the patency curve for the grafts with the 11 lowest value grafts was compared to the curve representing the 10 highest value grafts. The difference between high RL versus low RL patency curves was significant with high-resistance grafts having a median patency of 55 days and low-resistance grafts having a median patency greater than 151 days (p = 0.0089). In contrast, the high Q group median patency was 151 days versus 174 days for the low Q group (p = 0.86). Median patency for the low PGR group was 115 days compared to 62 days for the high PGR group (p = 0.162). Longitudinal resistance within AV grafts, but not flow or pressure gradient, showed a significant correlation with patency after thrombectomy. Increased resistance to flow within AV grafts appears to be an important factor affecting the propensity of dialysis grafts to thrombose. PMID:16959723

  5. Dialysis Access Graft Thrombolysis: Randomized Study of Pulse-Spray Versus Continuous Urokinase Infusion

    SciTech Connect

    Goodwin, Scott C.; Arora, Lokesh C.; Razavi, Mahmood K.; Sayre, James; McNamara, Thomas O.; Yoon, Chun

    1998-03-15

    Purpose: To compare pulse-spray to continuous-infusion thrombolysis with high-dose urokinase in thrombosed dialysis access grafts. Methods: A prospective randomized controlled trial was performed. From August 1992 to September 1993, 30 thrombosed polytetrafluoroethylene (PTFE) grafts in 24 patients were included, 15 grafts in each group. The success of thrombolysis, mean time to thrombolysis, mean urokinase dose, and 60-day patency rate were evaluated. Results: In the pulse-spray group, the mean time to thrombolysis was 72 min with a mean urokinase dose of 560,000 U. The 60-day patency rate was 71%. In the continuous-infusion group, the mean infusion time to thrombolysis was 55 min with a mean dose of 479,000 U. The 60-day patency rate was 73%. Conclusion: No statistically significant difference was found between the two techniques in the mean time to thrombolysis, the mean urokinase dose used, or the 60-day patency rate.

  6. Effect of a selective thromboxane synthase inhibitor on arterial graft patency and platelet deposition in dogs

    SciTech Connect

    McDaniel, M.D.; Huntsman, W.T.; Miett, T.O.; Cronenwett, J.L.

    1987-08-01

    This study examined the effect of selective thromboxane synthase inhibition and nonselective cyclooxygenase inhibition on vascular graft patency and indium 111-labeled platelet deposition in 35 mongrel dogs undergoing carotid artery replacement with 4 mm X 4 cm polytetrafluoroethylene (PTFE) (one side) and Dacron (opposite side) end-to-end grafts. Aspirin-dipyridamole therapy improved one-week graft patency, from 46% in untreated dogs to 93% in treated dogs. Thromboxane synthase inhibition (U-63557A) improved graft patency in these dogs to 81%. Both drug treatments reduced platelet deposition on Dacron and PTFE grafts by 48% to 68% compared with control dogs. Dacron grafts accumulated significantly more platelets than PTFE grafts but had comparable patency rates. Low-dose aspirin therapy had no significant effect on either graft patency or platelet deposition. All treatment groups showed a 60% to 76% reduction in serum thromboxane B2, but only thromboxane synthase inhibitor treatment increased plasma 6-keto-prostaglandin F1 alpha by 100%. Selective thromboxane synthase inhibition improved small-caliber prosthetic graft patency to the same extent as did conventional cyclooxygenase inhibition in this preliminary study.

  7. Statins Improve Long Term Patency of Arteriovenous Fistula for Hemodialysis

    PubMed Central

    Chang, Hao-Hsiang; Chang, Yu-Kang; Lu, Chia-Wen; Huang, Chi-Ting; Chien, Chiang-Ting; Hung, Kuan-Yu; Huang, Kuo-Chin; Hsu, Chih-Cheng

    2016-01-01

    The protective effects of statins against stenosis for permanent hemodialysis access have been repeatedly demonstrated in animal studies, but remain controversial in human studies. This study aims to evaluate the association between statin use and permanent hemodialysis access patency using a nationwide hemodialysis cohort. A total of 9862 pairs of statin users and non-users, matched by age and gender, were selected for investigation from 75404 new hemodialysis patients during 2000–2008. The effect of statins on permanent hemodialysis access patency was evaluated using Cox proportional hazards models. Compared with non-users, statin users had an overall 18% risk reduction in the composite endpoint in which angioplasty and recreation were combined (adjusted hazard ratio = 0.82 [95%CI, 0.78–0.87]) and 21% in recreation of permanent hemodialysis access (adjusted hazard ratio = 0.79 [95%CI, 0.69–0.80]). Specifically, the protective effect was found for arteriovenous fistula (adjusted hazard ratio = 0.78[95% CI, 0.73–0.82] for composite endpoint and 0.74 [95% CI, 0.69–0.80] for vascular recreation), but not for arteriovenous grafts (adjusted hazard ratio = 1.10 [95% CI, 0.98–1.24] and 0.94 [95% CI, 0.83–1.07]). Statins possess a protective effect for arteriovenous fistula against the recreation of permanent hemodialysis access. The results provide a pharmaco-epidemiologic link between basic research and clinical evidence. PMID:26902330

  8. 47 CFR 76.970 - Commercial leased access rates.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... collection, marketing, or studio services). (f) The maximum commercial leased access rate that a cable... collection, marketing, or studio services). Any subscriber revenue received by a cable operator for an a la... the provision of channel capacity, such as marketing, and excludes revenues. The affiliation fees...

  9. Mid-Term Patency in Radial Artery and Saphenous Vein After Coronary Artery Bypass Grafting in Asymptomatic Patients Using 128-Slice CT Coronary Angiography

    PubMed Central

    Sadeghpour, Ali; Pouraliakbar, Hamidreza; Azarfarin, Rasoul; Alizadeh Ghavidel, Alireza; Zavareian, Somayeh; Amirahmadi, Ali

    2015-01-01

    Background: Patency of the revascularization conduit is an essential predictor of long-standing survival after coronary artery bypass grafting. Objectives: We have conducted this study to compare the mid-term patency rates of radial artery (RA), left internal thoracic artery (LITA) and also saphenous vein (SV) grafts in asymptomatic patients following coronary artery bypass graft surgery (CABG) undergoing total IV anesthesia. Patients and Methods: In this study, 30 three-vessel disease patients with 104 RA, LITA, and SV grafts used concomitantly for primary isolated non-emergent CABG surgery were assessed. The primary end point was CT angiographic graft patency rate. After 53.5 (24-97) months’ follow-up, graft patency was assessed using 128-slice CT coronary angiography. Logistic regression analysis was used to detect the independent predictors of graft failure. Results: A total of 104 grafts, including 30 LITA, 44 SV, and 30 RA grafts, were studied. Cumulative graft patency rates were 93.3% in LITA, 83.3% in RA, and 70.5% in SV grafts. Statistically significant difference was found between the LITA and the SV graft patency rates (P = 0.019), whereas the difference between the RA conduit patency and the LITA or SV graft patency rates did not have any statistical significance (P = 0.424 and P = 0.273, respectively). Independent predictors of RA grafts occlusion were native coronary stenosis < 70% and female gender. Conclusions: In our patients, the RA grafts had an acceptable patency rate in 2 to 5 years’ follow-up. Although the SV grafts had a relatively higher patency rate than RA grafts in our asymptomatic patients, the patency rates in RA and SV grafts were close to each other. The RA graft function was poor in the patients with a higher number of risk factors and in the females. PMID:25789243

  10. Parylene MEMS patency sensor for assessment of hydrocephalus shunt obstruction.

    PubMed

    Kim, Brian J; Jin, Willa; Baldwin, Alexander; Yu, Lawrence; Christian, Eisha; Krieger, Mark D; McComb, J Gordon; Meng, Ellis

    2016-10-01

    Neurosurgical ventricular shunts inserted to treat hydrocephalus experience a cumulative failure rate of 80 % over 12 years; obstruction is responsible for most failures with a majority occurring at the proximal catheter. Current diagnosis of shunt malfunction is imprecise and involves neuroimaging studies and shunt tapping, an invasive measurement of intracranial pressure and shunt patency. These patients often present emergently and a delay in care has dire consequences. A microelectromechanical systems (MEMS) patency sensor was developed to enable direct and quantitative tracking of shunt patency in order to detect proximal shunt occlusion prior to the development of clinical symptoms thereby avoiding delays in treatment. The sensor was fabricated on a flexible polymer substrate to eventually allow integration into a shunt. In this study, the sensor was packaged for use with external ventricular drainage systems for clinical validation. Insights into the transduction mechanism of the sensor were obtained. The impact of electrode size, clinically relevant temperatures and flows, and hydrogen peroxide (H2O2) plasma sterilization on sensor function were evaluated. Sensor performance in the presence of static and dynamic obstruction was demonstrated using 3 different models of obstruction. Electrode size was found to have a minimal effect on sensor performance and increased temperature and flow resulted in a slight decrease in the baseline impedance due to an increase in ionic mobility. However, sensor response did not vary within clinically relevant temperature and flow ranges. H2O2 plasma sterilization also had no effect on sensor performance. This low power and simple format sensor was developed with the intention of future integration into shunts for wireless monitoring of shunt state and more importantly, a more accurate and timely diagnosis of shunt failure. PMID:27589973

  11. Predictors of the patency of self-expandable metallic stents in malignant gastroduodenal obstruction

    PubMed Central

    Kim, Seung Han; Chun, Hoon Jai; Yoo, In Kyung; Lee, Jae Min; Nam, Seung Joo; Choi, Hyuk Soon; Kim, Eun Sun; Keum, Bora; Seo, Yeon Seok; Jeen, Yoon Tae; Lee, Hong Sik; Um, Soon Ho; Kim, Chang Duck

    2015-01-01

    AIM: To investigate the predictive factors of self-expandable metallic stent patency after stent placement in patients with inoperable malignant gastroduodenal obstruction. METHODS: A total of 116 patients underwent stent placements for inoperable malignant gastroduodenal obstruction at a tertiary academic center. Clinical success was defined as acceptable decompression of the obstructive lesion within the malignant gastroduodenal neoplasm. We evaluated patient comorbidities and clinical statuses using the World Health Organization’s scoring system and categorized patient responses to chemotherapy using the Response Evaluation Criteria in Solid Tumors criteria. We analyzed the relationships between possible predictive factors and stent patency. RESULTS: Self-expandable metallic stent placement was technically successful in all patients (100%), and the clinical success rate was 84.2%. In a multivariate Cox proportional hazards model, carcinoembryonic antigen (CEA) levels were correlated with a reduction in stent patency [P = 0.006; adjusted hazard ratio (aHR) = 2.92, 95%CI: 1.36-6.25]. Palliative chemotherapy was statistically associated with an increase in stent patency (P = 0.009; aHR = 0.27, 95%CI: 0.10-0.72). CONCLUSION: CEA levels can easily be measured at the time of stent placement and may help clinicians to predict stent patency and determine the appropriate stent procedure. PMID:26290640

  12. Aortic Arch Calcification Predicts Patency Loss of Arteriovenous Fistula in End-Stage Renal Disease Patients

    PubMed Central

    Yap, Yit-Sheung; Ting, Kai-Ting; Chi, Wen-Che; Lin, Cheng-Hao; Liu, Yi-Chun; Chuang, Wan-Long

    2016-01-01

    Aortic arch calcification (AAC) is recognized as an important cardiovascular risk factor in patients with end-stage renal disease (ESRD). The aim of the study was to evaluate the impact of AAC grade on patency rates of arteriovenous fistula (AVF) in this specific population. The data of 286 ESRD patients who had an initial AVF placed were reviewed. The extent of AAC identified on chest radiography was divided into four grades (0–3). The association between AAC grade, other clinical factors, and primary patency of AVF was then analyzed by Cox proportional hazard analysis. The multivariate analysis demonstrated that the presence of AAC grade 2 (hazard ratio (95% confidence interval): 1.80 (1.15–2.84); p = 0.011) and grade 3 (3.03 (1.88–4.91); p < 0.001), and higher level of intact-parathyroid hormone (p = 0.047) were associated with primary patency loss of AVF. In subgroup analysis, which included AVF created by a surgeon assisted with preoperative vascular mapping, only AAC grade 3 (2.41 (1.45–4.00); p = 0.001), and higher intact-parathyroid hormone (p = 0.025) level were correlated with AVF patency loss. In conclusion, higher AAC grade and intact-parathyroid hormone level predicted primary patency loss of AVF in an ESRD population. PMID:27101807

  13. Efficacy of SMART Stent Placement for Salvage Angioplasty in Hemodialysis Patients with Recurrent Vascular Access Stenosis

    PubMed Central

    Hatakeyama, Shingo; Toikawa, Terumasa; Okamoto, Akiko; Yamamoto, Hayato; Imanishi, Kengo; Okamoto, Teppei; Tokui, Noriko; Suzuki, Yuichiro; Sugiyama, Naoki; Imai, Atsushi; Hashimoto, Yasuhiro; Kudo, Shigemasa; Yoneyama, Takahiro; Koie, Takuya; Kamimura, Noritaka; Saitoh, Hisao; Funyu, Tomihisa; Ohyama, Chikara

    2011-01-01

    Vascular access stenosis is a major complication in hemodialysis patients. We prospectively observed 50 patients in whom 50 nitinol shape-memory alloy-recoverable technology (SMART) stents were used as salvage therapy for recurrent peripheral venous stenosis. Twenty-five stents each were deployed in native arteriovenous fistula (AVF) and synthetic arteriovenous polyurethane graft (AVG) cases. Vascular access patency rates were calculated by Kaplan-Meier analysis. The primary patency rates in AVF versus AVG at 3, 6, and 12 months were 80.3% versus 75.6%, 64.9% versus 28.3%, and 32.3% versus 18.9%, respectively. The secondary patency rates in AVF versus AVG at 3, 6, and 12 months were 88.5% versus 75.5%, 82.6% versus 61.8%, and 74.4% versus 61.8%, respectively. Although there were no statistically significant difference in patency between AVF and AVG, AVG showed poor tendency in primary and secondary patency. The usefulness of SMART stents was limited in a short period of time in hemodialysis patients with recurrent vascular access stenosis. PMID:22164331

  14. Myocardial perfusion as an indicator of graft patency after coronary artery bypass surgery. [Thallium 201

    SciTech Connect

    Kolibash, A.J.; Call, T.D.; Bush, C.A.; Tetalman, M.R.; Lewis, R.P.

    1980-05-01

    Stress and resting myocardial perfusion were assessed in 38 patients who received 96 grafts. Stress perfusion was evaluated with thallium-201 and resting myocardial blood flow distribution with radiolabeled particles. When both stress and rest perfusion were normal, graft patency was 82% (51 of 62 grafts). Graft patency was also high (81%, 13 of 16) in areas where stress perfusion abnormalities resolved or become less apparent at rest. However, when stress perfusion defects remained unchanged at rest, the graf was likely to be occuluded (73%, 11 of 15). Maintenance of normal rest perfusion or improvement of rest perfusion postoperatively was also associated with a high graft patency rate (80%, 35 of 44), whereas the development of new rest perfusion defects postoperatively implied graft occlusion (86%, six of seven).

  15. Jaw thrust can deteriorate upper airway patency.

    PubMed

    von Ungern-Sternberg, B S; Erb, T O; Frei, F J

    2005-04-01

    Upper airway obstruction is a frequent problem in spontaneously breathing children undergoing anesthesia or sedation procedures. Failure to maintain a patent airway can rapidly result in severe hypoxemia, bradycardia, or asystole, as the oxygen demand of children is high and oxygen reserve is low. We present two children with cervical masses in whom upper airway obstruction exaggerated while the jaw thrust maneuver was applied during induction of anesthesia. This deterioration in airway patency was probably caused by medial displacement of the lateral tumorous tissues which narrowed the pharyngeal airway. PMID:15777312

  16. The importance of early patency after acute myocardial infarction.

    PubMed

    Grover, A; Rihal, C S

    1995-07-01

    The importance of achieving rapid patency of the infarct-related artery during acute myocardial infarction has become well recognized. Early, sustained patency of the infarct-related vessel correlates with improved left ventricular function, better in-hospital outcomes, and lower mortality. Various strategies designed to improve early patency, including "prehospital" thrombolysis, use of an accelerated recombinant tissue plasminogen activator regimen, and immediate angioplasty have been studied. This paper reviews the importance of achieving early patency, the various strategies employed, and the evidence for their efficacy. Future directions in treatment of acute myocardial infarction are touched upon briefly. PMID:7549077

  17. Patient-Derived Endothelial Progenitor Cells Improve Vascular Graft Patency in Rodent Model

    PubMed Central

    Stroncek, JD; Ren, LC; Klitzman, B; Reichert, WM

    2011-01-01

    Late outgrowth endothelial progenitor cells (EPCs) derived from the peripheral blood of patients with significant coronary artery disease were sodded into the lumens of small diameter expanded polytetrafluoroethylene (ePTFE) vascular grafts. Grafts (1 mm inner diameter) were denucleated and sodded either with native EPCs or with EPCs transfected with an adenoviral vector containing the gene for human thrombomodulin (EPC+AdTM). EPC+AdTM was shown to increase the in vitro rate of graft activated protein C (APC) production 4-fold over grafts sodded with untransfected EPCs (p<0.05). Unsodded control and EPC-sodded and EPC+AdTM-sodded grafts were implanted bilaterally into the femoral arteries of athymic rats for 7 or 28 days. Unsodded control grafts, both with and without denucleation treatment, each exhibited 7-day patency rates of 25%. Unsodded grafts showed extensive thrombosis and were not tested for patency over 28 days. In contrast, grafts sodded with untransfected EPCs or EPC+AdTM both had 7-day patency rates of 88-89% and 28-day patency rates of 75-88%. Intimal hyperplasia was observed near both the proximal and distal anastomoses in all sodded graft conditions but did not appear to be the primary occlusive failure event. This in vivo study suggests autologous EPCs derived from the peripheral blood of patients with coronary artery disease may improve the performance of synthetic vascular grafts, although no differences were observed between untransfected EPCs and TM transfected EPCs. PMID:21945828

  18. Patient-derived endothelial progenitor cells improve vascular graft patency in a rodent model.

    PubMed

    Stroncek, J D; Ren, L C; Klitzman, B; Reichert, W M

    2012-01-01

    Late outgrowth endothelial progenitor cells (EPCs) derived from the peripheral blood of patients with significant coronary artery disease were sodded into the lumens of small diameter expanded polytetrafluoroethylene (ePTFE) vascular grafts. Grafts (1mm inner diameter) were denucleated and sodded either with native EPCs or with EPCs transfected with an adenoviral vector containing the gene for human thrombomodulin (EPC+AdTM). EPC+AdTM was shown to increase the in vitro rate of graft activated protein C (APC) production 4-fold over grafts sodded with untransfected EPCs (p<0.05). Unsodded control and EPC-sodded and EPC+AdTM-sodded grafts were implanted bilaterally into the femoral arteries of athymic rats for 7 or 28 days. Unsodded control grafts, both with and without denucleation treatment, each exhibited 7 day patency rates of 25%. Unsodded grafts showed extensive thrombosis and were not tested for patency over 28 days. In contrast, grafts sodded with untransfected EPCs or EPC+AdTM both had 7 day patency rates of 88-89% and 28 day patency rates of 75-88%. Intimal hyperplasia was observed near both the proximal and distal anastomoses in all sodded graft conditions but did not appear to be the primary occlusive failure event. This in vivo study suggests autologous EPCs derived from the peripheral blood of patients with coronary artery disease may improve the performance of synthetic vascular grafts, although no differences were observed between untransfected EPCs and TM transfected EPCs. PMID:21945828

  19. 47 CFR 51.909 - Transition of rate-of-return carrier access charges.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Composite Terminating End Office Access Rate. (2) (f) Step 5. Beginning July 1, 2016, notwithstanding any... Access Service Rate as of July 1, 2016 and $0.0007 per minute. (ii) Beginning July 1, 2017, no Rate-of... Access Service Rate as of July 1, 2016 and $0.0007 per minute. (ii) Beginning July 1, 2018, no...

  20. One-Year Patency of Valvulotomized Vein Grafts Is Similar to That of Arterial Grafts.

    PubMed

    Monsefi, Nadejda; Zierer, Andreas; Honarpisheh, Gazal; Bauer, Ralf; Kerl, Matthias; Beiras-Fernandez, Andres; Moritz, Anton

    2016-04-01

    Background Inferior vein graft patency after coronary artery bypass grafting (CABG) is attributed to various factors. Venous valves may limit flow, cause thrombus formation, and diminish diastolic backflow. The aim of our study was to compare clinical outcome and midterm patency rate of valvulotomized vein grafts and arterial grafts in patients undergoing CABG. Methods Between 2007 and 2010, valvulotomized saphenous vein segments were used to graft the right coronary artery (RCA) in 147 patients undergoing CABG with mean 2.8 ± 1 arterial and 1.5 ± 0.6 venous anastomoses. Outcome, reintervention, and reoperation were assessed after 4 ± 1.6 years. Intraoperative bypass flow rate was measured before and after valvulotomy of venous bypass grafts in 12 patients. Patency of the grafts was assessed by means of multislice computed tomography (MSCT) in 45 patients. Results A total of 102 patients underwent isolated CABG and 45 had combined procedures. In-hospital mortality was 2%. At 4 years' clinical follow-up, 95% of the patients were asymptomatic. Five patients underwent recoronary angiography because of angina pectoris. The MSCT and reangiography patency rate of all valvulotomized saphenous vein grafts was 97.1 versus 95.8% of arterial grafts 18 ± 6 months postoperatively. Intraoperative measurements showed a significant increase (+20.2 mL/min; p = 0.01) of flow in the venous bypass grafts to the RCA after valvulotomy. There were no reoperations at the latest follow-up. Conclusion Patients with valvulotomized venous grafts had good clinical outcome. The one-year patency rate of those grafts is comparable to that of arterial grafts. However, long-term results and angiography studies will be needed to strengthen these findings. PMID:25866977

  1. Early Detection and Treatment of Hemodialysis Access Dysfunction

    SciTech Connect

    Gallego Beuter, Juan Jose; Hernandez Lezana, Antonio

    2000-01-15

    Purpose: To assess the usefulness of a program for the early detection of hemodialysis graft dysfunction and the impact on graft survival of percutaneous transluminal angioplasty (PTA) and stent implantation to correct venous stenosis.Methods: A program for the early detection of hemodialysis access graft dysfunction was carried out in 110 patients over a period of 80 months. Detection was based on physical examination, flow rate measurements, venous pressure, and analytical determinations performed at dialysis. The stenoses detected were treated by PTA or PTA plus stent deployment. Survival curves compared primary and assisted patency rates for the different graft types.Results: The most important indicators of dysfunction were increased venous pressure and difficulty in cannulation of the graft. Significant stenoses were revealed by 227 (92.2%) of the 246 fistulography procedures performed. PTA results were satisfactory in 100% of the Thomas grafts, 74% of the Brescia-Cimino (BC) grafts, and 53% of the polytetrafluoroethylene (PTFE) grafts. Technical success rates for stent deployment were 92% for BC grafts and 100% for PTFE grafts, while functional success rates were 96% and 97%, respectively. The difference in the primary patency (P1) and assisted patency (AP) values was statistically significant for all three graft types. There was no significant difference in the patency rates for grafts treated by PTA alone or by PTA and stent deployment.Conclusion: A surveillance program helped prevent graft thrombosis, and intervention as required achieved excellent primary and assisted patency rates. Stent deployment salvaged a considerable number of accesses but did not significantly extend access survival time.

  2. Endovascular Therapy for Femoropopliteal Artery Disease and Association of Risk Factors With Primary Patency: The Implication of Critical Limb Ischemia and TASC II C/D Disease.

    PubMed

    Nishibe, Toshiya; Yamamoto, Kiyohito; Seike, Yoshimasa; Ogino, Hitoshi; Nishibe, Masayasu; Koizumi, Jun; Dardik, Alan

    2015-11-01

    The treatment of femoropopliteal artery disease remains controversial, without clear guidelines specifying the indications for endovascular therapy (EVT). Accordingly, we retrospectively examined our experience of using EVT to treat femoropopliteal artery disease. A total of 91 limbs in 82 patients underwent EVT for the treatment of femoropopliteal artery disease. Percutaneous transluminal angioplasty alone was performed in 20 limbs, and additional stenting was performed in 71 limbs. The 1-year primary patency, primary-assisted patency, limb salvage, and survival rates were 76%, 88%, 96%, and 92%, respectively. Multivariate Cox analysis of primary patency showed that critical limb ischemia (CLI; hazard ratio [HR], 2.53; 95% confidence interval [CI], 1.08-5.33; P < .01) and TASC II C/D disease (HR, 2.70; 95% CI, 1.14-6.39; P < .05) were independent predictors of decreased primary patency. In conclusion, patients with CLI or extensive lesions have reduced patency after EVT for femoropopliteal artery disease. PMID:26574486

  3. Modelling high data rate communication network access protocol

    NASA Technical Reports Server (NTRS)

    Khanna, S.; Foudriat, E. C.; Paterra, Frank; Maly, Kurt J.; Overstreet, C. Michael

    1990-01-01

    Modeling of high data rate communication systems is different from the low data rate systems. Three simulations were built during the development phase of Carrier Sensed Multiple Access/Ring Network (CSMA/RN) modeling. The first was a model using SIMCRIPT based upon the determination and processing of each event at each node. The second simulation was developed in C based upon isolating the distinct object that can be identified as the ring, the message, the node, and the set of critical events. The third model further identified the basic network functionality by creating a single object, the node which includes the set of critical events which occur at the node. The ring structure is implicit in the node structure. This model was also built in C. Each model is discussed and their features compared. It should be stated that the language used was mainly selected by the model developer because of his past familiarity. Further the models were not built with the intent to compare either structure or language but because the complexity of the problem and initial results contained obvious errors, so alternative models were built to isolate, determine, and correct programming and modeling errors. The CSMA/RN protocol is discussed in sufficient detail to understand modeling complexities. Each model is described along with its features and problems. The models are compared and concluding observations and remarks are presented.

  4. Co-expression of fibulin-5 and VEGF165 increases long-term patency of synthetic vascular grafts seeded with autologous endothelial cells.

    PubMed

    Preis, M; Schneiderman, J; Koren, B; Ben-Yosef, Y; Levin-Ashkenazi, D; Shapiro, S; Cohen, T; Blich, M; Israeli-Amit, M; Sarnatzki, Y; Gershtein, D; Shofti, R; Lewis, B S; Shaul, Y; Flugelman, M Y

    2016-03-01

    Small caliber synthetic vascular grafts are commonly used for bypass surgery and dialysis access sites but have high failure rates because of neointima formation and thrombosis. Seeding synthetic grafts with endothelial cells (ECs) provides a biocompatible surface that may prevent graft failure. However, EC detachment following exposure to blood flow still remains a major obstacle in the development of biosynthetic grafts. We tested the hypothesis that induced expression by the seeded EC, of vascular endothelial growth factor165 (VEGF165) and of fibulin-5, an extracellular matrix glycoprotein that has a crucial role in elastin fiber organization and increase EC adherence to surfaces, may improve long-term graft patency. Autologous ECs were isolated from venous segments, and were transduced with retroviral vectors expressing fibulin-5 and VEGF165. The modified cells were seeded on expanded polytetrafluoroethylene (ePTFE) grafts and implanted in a large animal model. Three months after transplantation, all grafts seeded with modified EC were patent on a selective angiography, whereas only a third of the control grafts were patent. Similar results were shown at 6 months. Thus, seeding ePTFE vascular grafts with genetically modified EC improved long-term small caliber graft patency. The biosynthetic grafts may provide a novel therapeutic modality for patients with peripheral vascular disease and patients requiring vascular access for hemodialysis. PMID:26588709

  5. In vivo quantitative assessment of catheter patency in rats

    PubMed Central

    Yang, Jun; Maarek, Jean-Michel I; Holschneider, Daniel P

    2014-01-01

    Summary Formation of fibrin sleeves around catheter tips is a central factor in catheter failure during chronic implantation, and such tissue growth can occur despite administration of anticoagulants. We developed a novel method for monitoring catheter patency. This method recognizes the progressive nature of catheter occlusion, and tracks this process over time through measurement of changes in catheter resistance to a standardized 1 mL bolus infusion from a pressurized reservoir. Two indirect measures of catheter patency were used: (a) reservoir residual pressure and (b) reservoir discharge time. This method was applied to the study of catheter patency in rats comparing the effect of catheter material (silastic, polyurethane, Microrenathane™), lock solution (heparin, heparin/dexamethasone) and two different cannulation sites (superior vena cava via the external jugular vein, inferior vena cava via the femoral vein). Our findings reveal that application of flexible smaller-size silastic catheters and a dexamethasone lock solution resulted in prolonged catheter patency. Patency could be maintained over nine weeks with the femoral vein catheters, compared with five weeks with the external jugular vein catheters. The current method for measuring catheter patency provides a useful index for the assessment of tissue growth around the catheter tip. The method also provides an objective and quantitative way of comparing changes in catheter patency for different surgical methods and catheter types. Our method improves on the conventional method of assessing catheter occlusion by judging the ability to aspirate from the catheter. PMID:16004684

  6. 47 CFR 76.970 - Commercial leased access rates.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... access programmer for a full-time channel on that particular tier. The average implicit fee shall be... programmer's cost or the fair market value, whichever is lower. The average implicit fee shall be based on... that the operator may charge the leased access programmer for placement as a full-time a la...

  7. 47 CFR 76.970 - Commercial leased access rates.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... access programmer for a full-time channel on that particular tier. The average implicit fee shall be... programmer's cost or the fair market value, whichever is lower. The average implicit fee shall be based on... that the operator may charge the leased access programmer for placement as a full-time a la...

  8. The value of preoperative vascular imaging in the selection and success of hemodialysis access.

    PubMed

    Karakayali, Feza; Ekici, Yahya; Görür, Sarp K; Arat, Zübeyde; Boyvat, Fatih; Karakayali, Hamdi; Haberal, Mehmet

    2007-07-01

    The purpose of this study was to determine the value of preoperative vascular imaging (PVI) in the selection of an arteriovenous fistula (AVF) for hemodialysis with respect to site selection, maturation, patency, and functionality. We retrospectively evaluated 482 AVFs and arteriovenous grafts (AVGs) created in 321 patients who were regularly undergoing hemodialysis at our university's hemodialysis centers. The patients were divided into two groups according to PVI status. The patients in group 1 (n = 260) underwent Doppler ultrasonographic evaluation and venographic studies as well as physical examination before operation. The patients in group 2 (n = 222) underwent only physical examination before operation. Both groups were compared with respect to vascular access type, access maturation rate, and duration of access patency. In group 1, central veins were also evaluated for possible stenosis, and significant asymptomatic stenosis was treated with interventional techniques. The patients in group 1 were significantly older than those in group 2 and had a significantly higher mean number of previous central venous catheterizations and vascular access sites. At the initiation of the study, 234 of the vascular access sites had matured with a success rate of 90% in group 1. In group 2, however, 152 (68.5%) of the vascular access sites had matured. AVGs of the vascular access type were created in 31.5% of patients in group 1 and in 12.6% of patients in group 2. The mean duration of primary patency in group 1 overall (i.e., AVFs and AVGs) was 14.7 +/- 16.8 months, and the 6-month and 12-month patency rates were 72% and 46%, respectively. The mean duration of primary patency in group 2 overall was 11.9 +/- 9.4 months, and the 6-month and 12-month patency rates were 71% and 41%, respectively. Patients in group 1 had a significantly longer mean primary patency time than did those in group 2 (P = 0.024). Sixty-six cases of central vein stenosis were detected during PVI

  9. 47 CFR 51.909 - Transition of rate-of-return carrier access charges.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Access Rate. In the alternative, any Rate-of-Return Carrier may elect to implement a single per minute... elect to implement a single per minute rate element for terminating End Office Access Service no greater.... In the alternative, any Rate-of-Return Carrier may elect to implement a single per minute...

  10. An update of the effect of far infrared therapy on arteriovenous access in end-stage renal disease patients.

    PubMed

    Chen, Chun-Fan; Yang, Wu-Chang; Lin, Chih-Ching

    2016-07-12

    The life qualities of end-stage renal disease (ESRD) patients rely largely on adequate dialysis, and a well-functioning vascular access is indispensable for high quality hemodialysis. Despite the advancement of surgical skills and the optimal maintenance of arteriovenous fistula (AVF), malfunction of AVF is still frequently encountered and has great impact on the life of ESRD patients. Several medical, mechanical and genetic prognostic factors are documented to affect the patency of AVF and arteriovenous graft (AVG). Heme oxygenase-1 (HO-1) is one of the genetic factors reported to play a role in cardiovascular disease and the patency of vascular access. Far infrared (FIR), a novel therapeutic modality, can not only conduct heat energy to AVF but also stimulate the non-thermal reactions mediated by HO-1. The use of FIR therapy significantly enhances the primary patency rate and maturation of AVF with fewer unfavorable adverse effects, and also achieves higher post-angioplasty patency rate for AVG. The only limitation in proving the effectiveness of FIR therapy in enhancing patency of AVF is that all the studies were conducted in Chinese people in Taiwan and thus, there is a lack of evidence and experience in people of other ethnicities. PMID:27312759

  11. 47 CFR 76.970 - Commercial leased access rates.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... charge to programmers that predominantly transmit sales presentations or program length commercials for... access programmer for a full-time channel on that particular tier. The average implicit fee shall be... programmer's cost or the fair market value, whichever is lower. The average implicit fee shall be based...

  12. Open-Access Colleges Responsible for Greatest Gains in Graduation Rates. Policy Alert

    ERIC Educational Resources Information Center

    Doyle, William R.

    2010-01-01

    The largest gains in graduation rates over the past decade have been accomplished at open-access or nearly open-access colleges and universities. In addition, states could see even bigger increases if they directed their policies and supports toward improving graduation rates at these nonselective institutions. These findings from the author's…

  13. Labeling and Rating Systems: Greater Access or Censorship?

    ERIC Educational Resources Information Center

    Martin, Ann M.

    2015-01-01

    This article asks the question: How well versed are school librarians on issues related to labeling and rating systems? As school librarians continue to design and implement resource location schemes to assist patrons, they must recognize the difference between using labels to create interest in books or implementing labeling and rating systems…

  14. The value of sonography in determining cystic duct patency.

    PubMed

    McGrath, F P; Gibney, R G; Burhenne, H J

    1992-07-01

    A prospective blinded comparison of ultrasonography (US) and oral cholecystography (OCG) was performed in 100 patients with symptomatic gall-stones to determine whether US would enable an accurate assessment of cystic duct patency to be made. Patency of the cystic duct was defined as gall-bladder opacification on OCG or a greater than 20% decrease in gall-bladder volume by US post-fatty meal. The ellipsoid method of volume measurement was used. Any patient who had a non-opacified gall-bladder on OCG but a greater than 20% volume decrease on US had cholescintigraphy performed (DISIDA). Oral cholecystography demonstrated cystic duct patency in 88 patients (88%), and fatty-meal gall-bladder US met the specified study criteria for patency in 86 patients (86%). False negative results were identified in four of the OCG and in six of the US examinations. The results of this study indicate that gall-bladder sonography with a post-fatty meal contraction of greater than 20% is a very accurate predictor of cystic duct patency. A contraction of less than 20%, however, cannot be considered a reliable predictor of cystic duct occlusion. PMID:1643780

  15. Effect of Dipyridamole plus Aspirin on Hemodialysis Graft Patency

    PubMed Central

    Dixon, Bradley S.; Beck, Gerald J.; Vazquez, Miguel A.; Greenberg, Arthur; Delmez, James A.; Allon, Michael; Dember, Laura M.; Himmelfarb, Jonathan; Gassman, Jennifer J.; Greene, Tom; Radeva, Milena K.; Davidson, Ingemar J.; Ikizler, T. Alp; Braden, Gregory L.; Fenves, Andrew Z.; Kaufman, James S.; Cotton, James R.; Martin, Kevin J.; McNeil, James W.; Rahman, Asif; Lawson, Jeffery H.; Whiting, James F.; Hu, Bo; Meyers, Catherine M.; Kusek, John W.; Feldman, Harold I.

    2014-01-01

    BACKGROUND Arteriovenous graft stenosis leading to thrombosis is a major cause of complications in patients undergoing hemodialysis. Procedural interventions may restore patency but are costly. Although there is no proven pharmacologic therapy, dipyridamole may be promising because of its known vascular antiproliferative activity. METHODS We conducted a randomized, double-blind, placebo-controlled trial of extended-release dipyridamole, at a dose of 200 mg, and aspirin, at a dose of 25 mg, given twice daily after the placement of a new arteriovenous graft until the primary outcome, loss of primary unassisted patency (i.e., patency without thrombosis or requirement for intervention), was reached. Secondary outcomes were cumulative graft failure and death. Primary and secondary outcomes were analyzed with the use of a Cox proportional-hazards regression with adjustment for prespecified covariates. RESULTS At 13 centers in the United States, 649 patients were randomly assigned to receive dipyridamole plus aspirin (321 patients) or placebo (328 patients) over a period of 4.5 years, with 6 additional months of follow-up. The incidence of primary unassisted patency at 1 year was 23% (95% confidence interval [CI], 18 to 28) in the placebo group and 28% (95% CI, 23 to 34) in the dipyridamole–aspirin group, an absolute difference of 5 percentage points. Treatment with dipyridamole plus aspirin significantly prolonged the duration of primary unassisted patency (hazard ratio, 0.82; 95% CI, 0.68 to 0.98; P = 0.03) and inhibited stenosis. The incidences of cumulative graft failure, death, the composite of graft failure or death, and serious adverse events (including bleeding) did not differ significantly between study groups. CONCLUSIONS Treatment with dipyridamole plus aspirin had a significant but modest effect in reducing the risk of stenosis and improving the duration of primary unassisted patency of newly created grafts. (ClinicalTrials.gov number, NCT00067119.) PMID

  16. Saphenofemoral arteriovenous fistula as hemodialysis access

    PubMed Central

    2010-01-01

    Background An upper limb arteriovenous (AV) fistula is the access of choice for haemodialysis (HD). There have been few reports of saphenofemoral AV fistulas (SFAVF) over the last 10-20 years because of previous suggestions of poor patencies and needling difficulties. Here, we describe our clinical experience with SFAVF. Methods SFAVFs were evaluated using the following variables: immediate results, early and late complications, intraoperative and postoperative complications (up to day 30), efficiency of the fistula after the onset of needling and complications associated to its use. Results Fifty-six SFAVF fistulas were created in 48 patients. Eight patients had two fistulas: 8 patent (16%), 10 transplanted (20%), 12 deaths (24%), 1 low flow (2%) and 20 thrombosis (39%) (first two months of preparation). One patient had severe hypotension during surgery, which caused thrombosis of the fistula, which was successfully thrombectomised, four thrombosed fistulae were successfully thrombectomised and revised on the first postoperative day. After 59 months of follow-up, primary patency was 44%. Conclusion SFAVF is an adequate alternative for patients without the possibility for other access in the upper limbs, allowing efficient dialysis with good long-term patency with a low complication rate. PMID:20955561

  17. Noncontact imaging photoplethysmography to effectively access pulse rate variability.

    PubMed

    Sun, Yu; Hu, Sijung; Azorin-Peris, Vicente; Kalawsky, Roy; Greenwald, Stephen

    2013-06-01

    Noncontact imaging photoplethysmography (PPG) can provide physiological assessment at various anatomical locations with no discomfort to the patient. However, most previous imaging PPG (iPPG) systems have been limited by a low sample frequency, which restricts their use clinically, for instance, in the assessment of pulse rate variability (PRV). In the present study, plethysmographic signals are remotely captured via an iPPG system at a rate of 200 fps. The physiological parameters (i.e., heart and respiration rate and PRV) derived from the iPPG datasets yield statistically comparable results to those acquired using a contact PPG sensor, the gold standard. More importantly, we present evidence that the negative influence of initial low sample frequency could be compensated via interpolation to improve the time domain resolution. We thereby provide further strong support for the low-cost webcam-based iPPG technique and, importantly, open up a new avenue for effective noncontact assessment of multiple physiological parameters, with potential applications in the evaluation of cardiac autonomic activity and remote sensing of vital physiological signs. PMID:23111602

  18. Noncontact imaging photoplethysmography to effectively access pulse rate variability

    NASA Astrophysics Data System (ADS)

    Sun, Yu; Hu, Sijung; Azorin-Peris, Vicente; Kalawsky, Roy; Greenwald, Stephen

    2013-06-01

    Noncontact imaging photoplethysmography (PPG) can provide physiological assessment at various anatomical locations with no discomfort to the patient. However, most previous imaging PPG (iPPG) systems have been limited by a low sample frequency, which restricts their use clinically, for instance, in the assessment of pulse rate variability (PRV). In the present study, plethysmographic signals are remotely captured via an iPPG system at a rate of 200 fps. The physiological parameters (i.e., heart and respiration rate and PRV) derived from the iPPG datasets yield statistically comparable results to those acquired using a contact PPG sensor, the gold standard. More importantly, we present evidence that the negative influence of initial low sample frequency could be compensated via interpolation to improve the time domain resolution. We thereby provide further strong support for the low-cost webcam-based iPPG technique and, importantly, open up a new avenue for effective noncontact assessment of multiple physiological parameters, with potential applications in the evaluation of cardiac autonomic activity and remote sensing of vital physiological signs.

  19. 47 CFR 51.909 - Transition of rate-of-return carrier access charges.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...-Return Carrier may elect to implement a single per minute rate element for both interstate and intrastate... implement a single per minute rate element for both interstate and intrastate terminating End Office Access.... In the alternative, any Rate-of-Return Carrier may elect to implement a single per minute...

  20. Accessibility

    MedlinePlus

    ... www.nlm.nih.gov/medlineplus/accessibility.html MedlinePlus Accessibility To use the sharing features on this page, ... Subscribe to RSS Follow us Disclaimers Copyright Privacy Accessibility Quality Guidelines Viewers & Players MedlinePlus Connect for EHRs ...

  1. A study of coronary artery patency in relation to the index event in patients with myocardial infarction thrombolysed with streptokinase

    PubMed Central

    Gokhroo, R K; Gupta, Sajal; Bisht, Devendra Singh; Padmanabhan, Deepak

    2014-01-01

    Background Restoration of infarct vessel patency is the key treatment for acute ST-elevation myocardial infarction. Objective The purpose of the study was to confirm the effectiveness of streptokinase (STK) for successful thrombolysis of the infarct-related artery (IRA) in patients with acute myocardial infarction (AMI), in relation to the time of the index event and age compared with newer thrombolytic agents, in a tertiary care centre. Methods 100 patients (77% male) thrombolysed with STK underwent coronary angiography within 48 h of presentation. Patency of the IRA was used to assess successful thrombolysis. Results The mean pain-to-needle time was 3.24 h. 76 patients (76%) treated with thrombolysis had patent arteries with thrombolysis in myocardial infarction (TIMI) 2 or 3 flow. In subgroup analysis of time from the index event, patency rates were 83.3%, 77.5%, 68.7% and 40% in patients presenting within 0–2, 2–4, 4–6 and 6–12 h, respectively. In subgroup analysis, all patients less than 30 years of age had patent arteries with TIMI 2 or 3 flow. Coronary angiography showed the IRA was the left anterior descending artery (LAD) in 55%, the right coronary artery (RCA) in 33% and the left circumflex artery (LCX) in 12%. The patency rates of the LAD, RCA and LCX were 74.5%, 69.6% and 100%, respectively. Conclusions We found STK to be as effective as newer thrombolytic agents reported in other studies. In patients with AMI thrombolysed within 4 h, STK results in higher patency in young compared to older patients.

  2. Radial artery for coronary artery bypass grafting: does proximal anastomosis to the aorta or left internal mammary artery achieve better patency?

    PubMed

    Watson, Robert A; Hamza, Mustafa; Tsakok, Teresa M; Tsakok, Maria T

    2013-12-01

    A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'in coronary artery bypass grafting using radial artery grafts, does proximal anastomosis to the aorta or left internal mammary artery achieve better patency'. Altogether >183 papers were found using the reported search, of which 9 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Radial artery grafts typically have a narrower lumen than vein grafts, and as such there is some concern that anastomosing them directly to the aorta during coronary artery bypass grafting (CABG) may impair graft patency. As such, some surgeons prefer to anastomose radial artery grafts to a second-order vessel such as the left internal mammary artery (LIMA). We sought to assess the evidence for this. A handful of papers directly addressing the issue of the effect of the site of proximal anastomosis on graft patency were found, with three showing no significant difference. One such study reported an insignificant difference in angiographic patency at 32 months postoperatively, with 94.1% of off-aorta grafts remaining patent vs 87.2% of off-LIMA grafts (p = 0.123). However, a large-scale well-designed study was able to demonstrate a statistically significant difference at five years postoperatively, with 74.3% of off-aorta grafts patent, compared with 65.2% of off-LIMA (p = 0.004). Nonetheless, a number of papers that report patency for either off-aorta or off-LIMA grafts give comparable figures for each technique. Additionally, different centres and investigators report very different patency results for grafts that have the same site of proximal anastomosis. One centre was able to achieve patency rates for off-LIMA grafts of 88% up to a mean of 7.7 years postoperatively while another centre reported a patency rate

  3. Strategies for managing aortoiliac occlusions: access, treatment and outcomes

    PubMed Central

    Clair, Daniel G; Beach, Jocelyn M

    2015-01-01

    Treatment of severe aortoiliac disease has dramatically evolved from a dependence on open aortobifemoral grafting to hybrid and endovascular only approaches. Open surgery has been the gold standard treatment of severe aortoiliac disease with excellent patency rates, but with increased length of stay and major complications. In contrast, endovascular interventions can successfully treat almost any lesion with decreased risk, compared to open surgery. Although primary patency rates remain inferior, secondary endovascular interventions are often minor procedures resulting in comparable long-term outcomes. The risks of renal insufficiency, embolization and access complications are not insignificant; however, most can be prevented or managed without significant clinical consequence. Endovascular therapies should be considered a first-line treatment option for all patients with aortoiliac disease, especially those with high-risk cardiovascular comorbidities. PMID:25907618

  4. Graft Patency in Long-term Survivors after Renovisceral Debranching with VORTEC

    SciTech Connect

    Winklehner, Anna Nguyen-Kim, Thi Dan Linh Pfammatter, Thomas; Rancic, Zoran Mayer, Dieter Lachat, Mario; Frauenfelder, Thomas

    2015-06-15

    PurposeThis study was designed to evaluate retrospectively the long-term stent-graft patency after renovisceral revascularization with Viabahn Open Revascularization Technique (VORTEC) using computed tomography angiography (CTA) and magnetic resonance angiography (MRA).MethodsIn 34 patients (seven women; mean age 72 ± 8 years) with aortic aneurysm, 63 renovisceral vessels (i.e., 54 renal, nine visceral arteries) were revascularized with VORTEC between 2004 and 2009. All patients obtained a pre- and postinterventional CTA and at least one follow-up CTA or MRA after 6 or more months following intervention (median follow up: 43 months). Detection of bypass occlusion, bypass stenosis, infolding, stent-graft fractures and dislocations, and kidney shrinkage were noted by two readers in consensus. Furthermore, mortality during follow-up was assessed using the medical report.ResultsDuring follow-up, 12.6 % of stent-grafts occluded. Cumulative patency rate was 95.2 ± 2.7 % at 12 months, 87.7 ± 4.4 % at 24 and 36 months, and 84.7 ± 5.2 % at 48, 60, 72, 84, and 89 months, respectively. Overall, 19 % of stent-grafts (12/63) developed bypass stenosis (<50 %, 10 stent-grafts; > 50 %, 2 stent-grafts), in one case stenosis (>70 %) was suspected to be hemodynamically significant. No secondary dislocation, no infolding of renovisceral stent-grafts, and no stent-graft fracture occurred. Kidney shrinkage occurred in nine patients, primarily in patients with an occluded Viabahn (n = 7). Eleven patients (32.3 %) died within the follow-up time period.ConclusionsIn long-term survivors after VORTEC cumulative patency rate remained high, and no stent-graft fractures or secondary dislocations occurred.

  5. Using Acoustic Reflectometry to Determine Breathing Tube Position and Patency

    NASA Astrophysics Data System (ADS)

    Mansfield, J. P.; Wodicka, G. R.

    1995-11-01

    A new technique to guide and determine the patency of tubes placed within the human body was developed using the principles of time domain acoustic reflectometry. An audible sound pulse is introduced into the proximal end of the tube or catheter and the sonic reflections from the tube lumen and body cavity are analyzed to provide patency and position information, respectively. The information can be used to initially place the tube and monitor its position and patency thereafter. A dedicated instrument was developed for use with breathing tubes, known as endotracheal tubes (ETT), that are necessary for the mechanical ventilation of patients. The incident sound pulse is generated and it is measured along with the resulting reflections in a small wave tube connected to the ETT. When the ETT is properly placed in the trachea below the vocal folds, a characteristic reflection from the airways is measured and the timing between the incident pulse and this reflection is used to determine ETT position or movement. The reflection from the discontinuity between the distal ETT tip and the airway is used to estimate the diameter of the airway at this point. In addition, reflections from the ETT lumen are used to generate a profile of the lumen area over the length of the tube. This information allows reliable differentiation between proper and erroneous tube placement, quantification of movement over time, and provides the location and degree of obstructions within the lumen.

  6. Midterm Experience of Ipsilateral Axillary-Axillary Arteriovenous Loop Graft as Tertiary Access for Haemodialysis

    PubMed Central

    Hunter, J. P.; Nicholson, M. L.

    2014-01-01

    Objectives. To present a series of ipsilateral axillary artery to axillary vein loop arm grafts as an alternative vascular access procedure for haemodialysis in patients with difficult access. Design. Retrospective case series. Methods. Patients who underwent an axillary loop arteriovenous graft from September 2009 to September 2012 were included. Preoperative venous imaging to exclude central venous stenosis and to image arm/axillary veins was performed. A cuffed PTFE graft was anastomosed to the distal axillary artery and axillary vein and looped on the arm. Results. 25 procedures were performed on 22 patients. Median age was 51 years, with 9 males and 13 females. Median number of previous access procedures was 3 (range 0–7). Median followup was 16.4 months (range 1–35). At 3 months and 1 year, the primary and secondary patency rates were 70% and 72% and 36% and 37%, respectively. There were 11 radiological interventions in 6 grafts including 5 angioplasties and 6 thrombectomies. There were 19 surgical procedures in 10 grafts, including thrombectomy, revision, repair for bleeding, and excision. Conclusions. Our series demonstrates that the axillary loop arm graft yields acceptable early patency rates in a complex group of patients but to maintain graft patency required high rates of surgical and radiological intervention, in particular graft thrombectomy. PMID:24778864

  7. Fluctuations in Wikipedia access-rate and edit-event data

    NASA Astrophysics Data System (ADS)

    Kämpf, Mirko; Tismer, Sebastian; Kantelhardt, Jan W.; Muchnik, Lev

    2012-12-01

    Internet-based social networks often reflect extreme events in nature and society by drastic increases in user activity. We study and compare the dynamics of the two major complex processes necessary for information spread via the online encyclopedia ‘Wikipedia’, i.e., article editing (information upload) and article access (information viewing) based on article edit-event time series and (hourly) user access-rate time series for all articles. Daily and weekly activity patterns occur in addition to fluctuations and bursting activity. The bursts (i.e., significant increases in activity for an extended period of time) are characterized by a power-law distribution of durations of increases and decreases. For describing the recurrence and clustering of bursts we investigate the statistics of the return intervals between them. We find stretched exponential distributions of return intervals in access-rate time series, while edit-event time series yield simple exponential distributions. To characterize the fluctuation behavior we apply detrended fluctuation analysis (DFA), finding that most article access-rate time series are characterized by strong long-term correlations with fluctuation exponents α≈0.9. The results indicate significant differences in the dynamics of information upload and access and help in understanding the complex process of collecting, processing, validating, and distributing information in self-organized social networks.

  8. Clinical utility of far-infrared therapy for improvement of vascular access blood flow and pain control in hemodialysis patients

    PubMed Central

    Choi, Soo Jeong; Cho, Eun Hee; Jo, Hye Min; Min, Changwook; Ji, Young Sok; Park, Moo Yong; Kim, Jin Kuk; Hwang, Seung Duk

    2015-01-01

    Background Maintenance of a well-functioning vascular access and minimal needling pain are important goals for achieving adequate dialysis and improving the quality of life in hemodialysis (HD) patients. Far-infrared (FIR) therapy may improve endothelial function and increase access blood flow (Qa) and patency in HD patients. The aim of this study was to evaluate effects of FIR therapy on Qa and patency, and needling pain in HD patients. Methods This prospective clinical trial enrolled 25 outpatients who maintained HD with arteriovenous fistula. The other 25 patients were matched as control with age, sex, and diabetes. FIR therapy was administered for 40 minutes during HD 3 times/wk and continued for 12 months. The Qa was measured by the ultrasound dilution method, whereas pain was measured by a numeric rating scale at baseline, then once per month. Results One patient was transferred to another facility, and 7 patients stopped FIR therapy because of an increased body temperature and discomfort. FIR therapy improved the needling pain score from 4 to 2 after 1 year. FIR therapy increased the Qa by 3 months and maintained this change until 1 year, whereas control patients showed the decrease in Qa. The 1-year unassisted patency with FIR therapy was not significantly different from control. Conclusion FIR therapy improved needling pain. Although FIR therapy improved Qa, the unassisted patency was not different compared with the control. A larger and multicenter study is needed to evaluate the effect of FIR therapy. PMID:27069856

  9. Racial Differences in Clostridium difficile Infection Rates Are Attributable to Disparities in Health Care Access.

    PubMed

    Mao, Eric J; Kelly, Colleen R; Machan, Jason T

    2015-10-01

    This study confirms previously reported racial differences in Clostridium difficile infection (CDI) rates in the United States and explores the nature of those differences. We conducted a retrospective study using the 2010 Nationwide Inpatient Sample, the largest all-payer database of hospital discharges in the United States. We identified hospital stays most likely to include antibiotic treatment for infections, based on hospital discharge diagnoses, and we examined how CDI rates varied, in an attempt to distinguish between genotypic and environmental racial differences. Logistic regressions for the survey design were used to test hypotheses. Among patients likely to have received antibiotics, white patients had higher CDI rates than black, Hispanic, Asian, and Native American patients (P < 0.0001). CDI rates increased with higher income levels and were higher for hospitalizations paid by private insurance versus those paid by Medicaid or classified as self-pay or free care (P < 0.0001). Among patients admitted from skilled nursing facilities, where racial bias in health care access is less, racial differences in CDI rates disappeared (P = 1.0). Infected patients did not show racial differences in rates of complicated CDI or death (P = 1.0). Although white patients had greater CDI rates than nonwhite patients, racial differences in CDI rates disappeared in a population for which health care access was presumed to be less racially biased. This provides evidence that apparent racial differences in CDI risks may represent health care access disparities, rather than genotypic differences. CDI represents a deviation from the paradigm that increased health care access is associated with less morbidity. PMID:26248363

  10. Health Benefits for Vocational Rehabilitation Consumers: Comparison of Access Rates with Workers in the General Population

    ERIC Educational Resources Information Center

    Lustig, Daniel C.; Strauser, David R.

    2010-01-01

    Access to health insurance is one of the critical aspects of securing employment for people with disabilities. This study investigated whether vocational rehabilitation consumers secured employment with an employer who offered health insurance at similar rates to workers in the general population. In general, the results show that vocational…

  11. Impact of off-pump coronary artery bypass surgery on graft patency: current best available evidence.

    PubMed

    Raja, Shahzad G; Dreyfus, Gilles D

    2007-01-01

    For more than three decades cardiac surgeons have been used to perform delicate coronary anastomoses on cardiopulmonary bypass (CPB). However, the price of a still and bloodless field is ultimately paid by the patients in the form of sequelae of negative effects of CPB including blood trauma, activation of a series of inflammatory responses, nonpulsatile flow, and possible embolization of air or debris. In an attempt to avoid these deleterious effects of CPB, off-pump coronary artery bypass surgery (OPCAB) has been rediscovered and refined. Although abundant evidence is available to suggest that excellent results can be achieved when CPB is avoided, concerns have been raised about quality of anastomosis and graft patency rates after OPCAB surgery. We are currently practicing in an era of evidence-based medicine that mandates the prospective randomized controlled trial (RCT) as the most accurate tool for determining a treatment benefit compared with a control population. This review article attempts to evaluate the current best available evidence from RCTs on the impact of OPCAB surgery on graft patency. PMID:17338760

  12. Transcervical catheterization and cervical patency during the oestrous cycle in domestic cats.

    PubMed

    Chatdarong, K; Lohachit, C; Ponglowhapan, S; Linde-Forsberg, C

    2001-01-01

    The aims of the present study were to develop a device for vaginal and transcervical catheterization in domestic cats, and to study cervical patency during the various stages of the oestrous cycle. Seventeen queens submitted for routine spaying were included in the study. A vaginal catheter was designed from a urinary catheter for dogs, to fit into the ventral vaginal fornix, and a 3.5 French tomcat catheter was used as an inner transcervical catheter. Cervical patency was studied by infusing 0.5 ml Urografin into the cranial vagina and taking X-rays of the queens after 5 min. The Urografin did not enter the uterus, even in the oestrous queens. Transcervical catheterization was then attempted. The correct placement of the intrauterine catheter was confirmed by injecting green food colour mixed with penicillin G and observing the presence of stain in the uterine horns during surgery. Catheterization was successful in 13 of 17 queens: six of nine in interoestrus, three of three in oestrus, one of two in metoestrus and three of three in the postpartum period. Transcervical catheterization is a non-invasive technique that is likely to improve the success rate of assisted feline reproduction, and is potentially a useful non-surgical technique for diagnosis and therapy of uterine diseases. PMID:11787175

  13. Assessment of nasal patency after rhinoplasty through the Glatzel mirror

    PubMed Central

    de Pochat, Victor Diniz; Alonso, Nivaldo; Mendes, Rogério Rafael da Silva; Gravina, Paula Rocha; Cronenberg, Eduardo Valente; Meneses, José Valber Lima

    2012-01-01

    Summary Introduction: Objective evaluation of nasal function is a constant challenge for plastic surgeons, otolaryngologists, and allergists. The modified Glatzel mirror can evaluate nasal expiratory flow; however, there is little information on this method and its use in the measurement of nasal patency after surgical procedures. Objective: To compare, in a prospective study, the functional results before and after cosmetic rhinoplasty and evaluate the use of the Glatzel mirror as an objective method to assess nasal patency. Methods: To achieve this objective, we analyzed the functional results of surgery through a subjective questionnaire and objective evaluation through a modified Glatzel mirror, and evaluated the correlation between the 2 methods. Twenty patients (14 women and 6 men) underwent aesthetic rhinoplasty using spreader grafts. Pre- and postoperative evaluation (90–120 days) included a respiratory quality score (subjective) and modified Glatzel mirror test (objective). Subsequently, the Spearman test was used to compare the pre- and postoperative subjective and objective data. Results: The subjective evaluation demonstrated a statistical difference between pre- and postoperative scores (8 ± 2 and 9.4 ± 0.7, P ≤ 0.001). There was no statistical difference in mean nasal patency by modified Glatzel mirror. No statistically significant correlation was observed when comparing the modified Glatzel mirror values with the subjective scores reported by patients pre- or postoperatively. Conclusion: The Glatzel method lacks sensitivity in detecting patient-reported improvements in breathing following rhinoplasty. This suggests that the method is a poor assessment tool to detect small, post-surgical changes in the nasal airways. PMID:25991955

  14. Irrigation with N,N-dichloro-2,2-dimethyltaurine (NVC-422) in a citrate buffer maintains urinary catheter patency in vitro and prevents encrustation by Proteus mirabilis.

    PubMed

    Rani, Suriani Abdul; Celeri, Chris; Najafi, Ron; Bley, Keith; Debabov, Dmitri

    2016-06-01

    Long-term use of indwelling urinary catheters can lead to urinary tract infections and loss of catheter patency due to encrustation and blockage. Encrustation of urinary catheters is due to formation of crystalline biofilms by urease-producing microorganisms such as Proteus mirabilis. An in vitro catheter biofilm model (CBM) was used to evaluate current methods for maintaining urinary catheter patency. We compared antimicrobial-coated urinary Foley catheters, with both available catheter irrigation solutions and investigational solutions containing NVC-422 (N,N-dichloro-2,2-dimethyltaurine; a novel broad-spectrum antimicrobial). Inoculation of the CBM reactor with 10(8) colony-forming units of P. mirabilis resulted in crystalline biofilm formation in catheters by 48 h and blockage of catheters within 5 days. Silver hydrogel or nitrofurazone-coated catheters did not extend the duration of catheter patency. Catheters irrigated daily with commercially available solutions such as 0.25 % acetic acid and isotonic saline blocked at the same rate as untreated catheters. Daily irrigations of catheters with 0.2 % NVC-422 in 10 mM acetate-buffered saline pH 4 or Renacidin maintained catheter patency throughout 10-day studies, but P. mirabilis colonization of the CBM remained. In contrast, 0.2 % NVC-422 in citrate buffer (6.6 % citric acid at pH 3.8) resulted in an irrigation solution that not only maintained catheter patency for 10 days but also completely eradicated the P. mirabilis biofilm within one treatment day. These data suggest that an irrigation solution containing the rapidly bactericidal antimicrobial NVC-422 in combination with citric acid to permeabilize crystalline biofilm may significantly enhance catheter patency versus other approved irrigation solutions and antimicrobial-coated catheters. PMID:26282899

  15. Endovascular Revascularization of Chronically Thrombosed Arteriovenous Fistulas and Grafts for Hemodialysis: A Retrospective Study in 15 Patients With 18 Access Sites

    SciTech Connect

    Weng Meijui; Chen, Matt Chiung-Yu; Chi Wenche; Liu Yichun; Liang, Huei-Lung; Pan, Huay-Ben

    2011-04-15

    The current study retrospectively evaluated whether endovascular revascularization of chronically thrombosed and long-discarded vascular access sites for hemodialysis was feasible. Technical and clinical success rates, postintervention primary and secondary patency rates, and complications were reported. During a 1-year period, we reviewed a total of 924 interventions performed for dysfunction and/or failed hemodialysis vascular access sites and permanent catheters in 881 patients. In patients whose vascular access-site problems were considered untreatable or were considered treatable with a high risk of failure and access-site abandonment, we attempted to revascularize (resurrect) the chronically occluded and long-discarded (mummy) vascular access sites. We attempted to resurrect a total of 18 mummy access sites (mean age 46.6 {+-} 38.7 months; range 5-144) in 15 patients (8 women and 7 men; mean age 66.2 {+-} 11.5 years; age range 50-85) and had an overall technical success rate of 77.8%. Resurrection failure occurred in 3 fistulas and in 1 straight graft. The clinical success rate was 100% at 2 months after resurrection. In the 14 resurrected vascular access sites, 6 balloon-assisted maturation procedures were required in 5 fistulas; after access-site maturation, a total of 22 interventions were performed to maintain access-site patency. The mean go-through time for successful resurrection procedures was 146.6 {+-} 34.3 min (range 74-193). Postmaturation primary patency rates were 71.4 {+-} 12.1% at 30 days, 57.1 {+-} 13.2% at 60 days, 28.6 {+-} 13.4% at 90 days, and 19 {+-} 11.8% at 180 days. Postmaturation secondary patency rates were 100% at 30, 60, and 90 days and 81.8 {+-} 11.6% at 180 days. There were 2 major complications consisting of massive venous ruptures in 2 mummy access sites during balloon dilation; in both cases, prolonged balloon inflation failed to achieve hemostasis, but percutaneous N-butyl cyanoacrylate glue seal-off was performed

  16. Arterioarterial Prosthetic Loop as an Alternative Approach for Hemodialysis Access

    PubMed Central

    Lei, Wenhui; Ji, Jiansong; Wang, Jian; Jin, Lie; Zou, Hai

    2015-01-01

    Abstract In the present study, we performed an arterioarterial prosthetic loop (AAPL) between the femoral artery and deep femoral artery as a new access in patients who did not have adequate vascular conditions for creating an arteriovenous fistula or graft. Between April 2005 and June 2014, 18 patients received AAPL as a vascular access. During the procedure, a polytetrafluoroethylene graft was anastomosed to the femoral artery and deep femoral artery and looped on the thigh. We assessed the reliability and safety of AAPLs by analyzing complication, primary and secondary patency rates, and postoperative blood flow. Eighteen patients (median age, 66 years; range, 43–96 years) underwent AAPL access placement under the general or local anesthesia. All patients were followed up for 3 to 38 months (mean, 24 months). Primary and secondary patency rates at 6 months were 94.5% and 88.8%, respectively, and at 3 years were 61% and 72%, respectively. After operation, one patient had infection, and another one had fat necrosis at the surgical incision site. To maintain the AAPL function, 5 surgical procedures in 4 grafts, including revision, thrombectomy, excision, and repair for bleeding were performed. More than 5000 hemodialyses were performed efficiently in our center. Our study shows that AAPL loop is an unusual but effective and safe procedure that may be a good alternative for the patients who do not allow the conventional hemodialysis access. PMID:26469899

  17. Does really previous stenting affect graft patency following CABG? A 5-year follow-up: The effect of PCI on graft survival.

    PubMed

    Songur, Murat Çetin; Özyalçin, Sertan; Özen, Anıl; Şimşek, Erdal; Kervan, Ümit; Taşoğlu, İrfan; Kaplan, Sadi; Köse, Kenan; Ulus, Ahmet Tulga

    2016-04-01

    The aim of this study was to compare the graft patency rates among patients who had a previous history of percutaneous coronary intervention (PCI) followed by coronary artery bypass grafting surgery (CABG) with the patients who had experienced CABG surgery alone. The 69 patients who were included in the study had a history of bare metal stent implantation prior to CABG (group 1). The coronary angiography results were compared with 69 patients who had a previous history of CABG (group 2). Graft patency rates of the left anterior descending artery and circumflex anastomoses are statistically significant for both groups, whereas the right coronary artery anastomoses are not statistically significant (p = 0.008; 0.009; 0.2). Graft patency rate of LIMA-LAD anastomoses was 43.9 ± 10.8 % in group 1 and 86.2 ± 6 % in group 2 for means of 60 months (p = 0.0001) and circumflex coronary artery anastomosis is 28.9 ± 0.9 % in group 1, 65.7 ± 10.8 % in group 2 (p = 0.0001) and the right coronary artery anastomosis is 37.2 ± 13.6 % in group 1, 56.4 ± 8.9 % in group 2 (p = 0.0001). The graft patency rates of coronary arteries without previous stent implantation were higher than the patients with previous stent implantation and experienced CABG. The results suggest that prior PCI may induce atherosclerotic events in the vessel that can adversely affect graft patency after surgery. PMID:25637043

  18. Scintisplenoportography in assessing patency of distal splenorenal shunts

    SciTech Connect

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

    1983-06-01

    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.

  19. Pediatric cardiac catheterization procedure with dexmedetomidine sedation: Radiographic airway patency assessment

    PubMed Central

    Thimmarayappa, Ashwini; Chandrasekaran, Nivash; Jagadeesh, A. M.; Joshi, Shreedhar S.

    2015-01-01

    Aims: The aim of the study was to measure airway patency objectively during dexmedetomidine sedation under radiographic guidance in spontaneously breathing pediatric patients scheduled for cardiac catheterization procedures. Subjects and Methods: Thirty-five patients in the age group 5–10 years scheduled for cardiac catheterization procedures were enrolled. All study patients were given loading dose of dexmedetomidine at 1 μg/kg/min for 10 min and then maintenance dose of 1.5 μg/kg/h. Radiographic airway patency was assessed at the start of infusion (0 min) and after 30 min. Antero-posterior (AP) diameters were measured manually at the nasopharyngeal and retroglossal levels. Dynamic change in airway between inspiration and expiration was considered a measure of airway collapsibility. Patients were monitored for hemodynamics, recovery time and complications. Statistical Analysis: Student paired t-test was used for data analysis. P < 0.05 was considered significant. Results: Minimum and maximum AP diameters were compared at 0 and 30 min. Nasopharyngeal level showed significant reduction in the minimum (6.27 ± 1.09 vs. 4.26 ± 1.03, P < 0.0001) and maximum (6.51 ± 1.14 vs. 5.99 ± 1.03, P < 0.0001) diameters. Similarly retroglossal level showed significant reduction in the minimum (6.98 ± 1.09 vs. 5.27 ± 1.15, P < 0.0001) and maximum (7.49 ± 1.22 vs. 6.92 ± 1.12, P < 0.0003) diameters. The degree of collapsibility was greater at 30 min than baseline (P < 0.0001). There was a significant decrease in heart rate (P < 0.0001), and the average recovery time was 39.86 ± 12.22 min. Conclusion: Even though airway patency was maintained in all children sedated with dexmedetomidine, there were significant reductions in the upper airway dimensions measured, so all precautions to manage the airway failure should be taken. PMID:25566708

  20. The relationship between relative solvent accessibility and evolutionary rate in protein evolution.

    PubMed

    Ramsey, Duncan C; Scherrer, Michael P; Zhou, Tong; Wilke, Claus O

    2011-06-01

    Recent work with Saccharomyces cerevisiae shows a linear relationship between the evolutionary rate of sites and the relative solvent accessibility (RSA) of the corresponding residues in the folded protein. Here, we aim to develop a mathematical model that can reproduce this linear relationship. We first demonstrate that two models that both seem reasonable choices (a simple model in which selection strength correlates with RSA and a more complex model based on RSA-dependent amino acid distributions) fail to reproduce the observed relationship. We then develop a model on the basis of observed site-specific amino acid distributions and show that this model behaves appropriately. We conclude that evolutionary rates are directly linked to the distribution of amino acids at individual sites. Because of this link, any future insight into the biophysical mechanisms that determine amino acid distributions will improve our understanding of evolutionary rates. PMID:21467571

  1. A carrier sensed multiple access protocol for high data base rate ring networks

    NASA Technical Reports Server (NTRS)

    Foudriat, E. C.; Maly, Kurt J.; Overstreet, C. Michael; Khanna, S.; Paterra, Frank

    1990-01-01

    The results of the study of a simple but effective media access protocol for high data rate networks are presented. The protocol is based on the fact that at high data rates networks can contain multiple messages simultaneously over their span, and that in a ring, nodes used to detect the presence of a message arriving from the immediate upstream neighbor. When an incoming signal is detected, the node must either abort or truncate a message it is presently sending. Thus, the protocol with local carrier sensing and multiple access is designated CSMA/RN. The performance of CSMA/RN with TTattempt and truncate is studied using analytic and simulation models. Three performance factors, wait or access time, service time and response or end-to-end travel time are presented. The service time is basically a function of the network rate, it changes by a factor of 1 between no load and full load. Wait time, which is zero for no load, remains small for load factors up to 70 percent of full load. Response time, which adds travel time while on the network to wait and service time, is mainly a function of network length, especially for longer distance networks. Simulation results are shown for CSMA/RN where messages are removed at the destination. A wide range of local and metropolitan area network parameters including variations in message size, network length, and node count are studied. Finally, a scaling factor based upon the ratio of message to network length demonstrates that the results, and hence, the CSMA/RN protocol, are applicable to wide area networks.

  2. Patency of heart blood vessels under photosensitization reaction shortly after intravenous injection of talaporfin sodium in canine model

    NASA Astrophysics Data System (ADS)

    Hamada, Risa; Matsuzaki, Ryota; Ogawa, Emiyu; Arai, Tsunenori

    2016-03-01

    In order to investigate patency of heart blood vessels by photosensitization reaction shortly after intravenous injection of talaporfin sodium, we performed in vitro endothelial cell lethality study and in vivo study of heart blood vessel patency in canine one week after photosensitization reaction. Cell lethality of human umbilical vein endothelial cells under different albumin concentrations corresponding with blood and interstice concentrations were employed and their lethality 2 hours after the reaction was measured by WST assay in vitro. Almost all cells survived by 40 J/cm2 photosensitization reaction with blood albumin concentration. Laser diffuser made of plastic optical fiber with 70 mm in length was used in vivo. Red diode laser of 664nm wavelength was emitted from this diffuser with 17.1-42.9 mW/cm in 10 minutes. We estimated the fluence rate distribution by a ray-trace simulator using pre-measured optical coefficients of myocardium tissue, μa 0.12 mm-1 and μs' 0.36 mm-1. Almost all blood vessels were patent in every irradiation conditions in canine heart. Coronary artery and vein up to 1 mm diameter were patent in typical myocardium sample with 25.7 mW/cm. We estimated fluence rate distribution of this sample and found that blood vessels were patent even fluence rate over 40 J/cm2. This in vivo study could be explained by the result of in vitro study. We suggest that this blood vessel patency after our particular photosensitization reaction might be because of few photosensitizer uptake in the blood endothelial cells and/or reduced oxidation damage by thick albumin concentration in blood.

  3. Pediatric appendicitis rupture rate: a national indicator of disparities in healthcare access.

    PubMed

    Jablonski, Kathleen A; Guagliardo, Mark F

    2005-05-01

    BACKGROUND: The U.S. National Healthcare Disparities Report is a recent effort to measure and monitor racial and ethnic disparities in health and healthcare. The Report is a work in progress and includes few indicators specific to children. An indicator worthy of consideration is racial/ethnic differences in the rate of bad outcomes for pediatric acute appendicitis. Bad outcomes for this condition are indicative of poor access to healthcare, which is amenable to social and healthcare policy changes. METHODS: We analyzed the KID Inpatient Database, a nationally representative sample of pediatric hospitalization, to compare rates of appendicitis rupture between white, African American, Hispanic and Asian children. We ran weighted logistic regression models to obtain national estimates of relative odds of rupture rate for the four groups, adjusted for developmental, biological, socioeconomic, health services and hospital factors that might influence disease outcome. RESULTS: Rupture was a much more burdensome outcome than timely surgery and rupture avoidance. Rupture cases had 97% higher hospital charges and 175% longer hospital stays than non-rupture cases on average. These burdens disproportionately affected minority children, who had 24% - 38% higher odds of appendicitis rupture than white children, adjusting for age and gender. These differences were reduced, but remained significant after adjusting for other factors. CONCLUSION: The racial/ethnic disparities in pediatric appendicitis outcome are large and are preventable with timely diagnosis and surgery for all children. Furthermore, estimating this disparity using the KID survey is a relatively straightforward process. Therefore pediatric appendicitis rupture rate is a good candidate for inclusion in the National Healthcare Disparities Report. As with most other health and healthcare disparities, efforts to reduce disparities in income, wealth and access to care will most likely improve the odds of favorable

  4. Primary Patency of Wallstents in Malignant Bile Duct Obstruction: Single vs. Two or More Noncoaxial Stents

    SciTech Connect

    Maybody, Majid Brown, Karen T.; Brody, Lynn A.; Covey, Anne M.; Sofocleous, Constantinos T.; Thornton, Raymond H.; Getrajdman, George I.

    2009-07-15

    The purpose of this study was to determine the primary patency of two or more noncoaxial self-expanding metallic Wallstents (Boston Scientific, Natick, MA) and to compare this with the primary patency of a single stent in malignant bile duct obstruction. From August 2002 to August 2004, 127 patients had stents placed for malignant bile duct obstruction. Forty-five patients were treated with more than one noncoaxial self-expanding metallic stents and 82 patients had a single stent placed. Two patients in the multiple-stent group were lost to follow-up. The primary patency period was calculated from the date of stenting until the first poststenting intervention for stent occlusion, death, or the time of last documented follow-up. The patency of a single stent was significantly different from that of multiple stents (P = 0.0004). In the subset of patients with high bile duct obstruction, the patency of a single stent remained significantly different from that of multiple stents (P = 0.02). In the single-stent group, there was no difference in patency between patients with high vs. those with low bile duct obstruction (P = 0.43). The overall median patency for the multistent group and the single-stent group was 201 and 261 days, respectively. In conclusion, the patency of a single stent placed for malignant low or high bile duct obstruction is similar, and significantly longer than, that of multiple stents placed for malignant high bile duct obstruction. Given the median patency of 201 days, when indicated, percutaneous stenting of multiple bile ducts is an effective palliative measure for patients with malignant high bile duct obstruction.

  5. Percutaneous Intraductal Radiofrequency Ablation Combined with Biliary Stent Placement for Nonresectable Malignant Biliary Obstruction Improves Stent Patency but not Survival

    PubMed Central

    Wang, Jianfeng; Zhao, Lizhen; Zhou, Chuanguo; Gao, Kun; Huang, Qiang; Wei, Baojie; Gao, Jun

    2016-01-01

    Abstract Although radiofrequency (RF) ablation has been accepted as a curative treatment modality for solid organ tumors, intraductal RF ablation for malignant biliary obstruction has not been widely described. The aim of this study was to evaluate the feasibility, safety, and efficacy (in terms of stent patency and survival) of intraductal RF ablation combined with biliary stent placement for nonresectable malignant biliary obstruction. A search of the nonresectable malignant extrahepatic biliary obstruction database (179 patients) identified 18 consecutive patients who were treated with biliary intraluminal RF ablation during percutaneous transhepatic cholangiodrainage and inner stent placement (RF ablation group) and 18 patients who underwent inner stent placement without biliary intraluminal RF ablation (control group). The patients were matched for tumor type, location of obstruction, tumor stage, and Child–Pugh class status. Primary endpoints included safety, stent patency time, and survival rates. The secondary endpoint was effectiveness of the technique. The RF ablation and control groups were closely matched in terms of age, diagnosis, presence of metastases, presence of locally advanced tumor, American Society of Anesthesiologists (ASA) grade, and chemotherapy regimen (all P > 0.05). The technical success rate for both groups was 100%. The median time of stent patency in the RF ablation and control groups were 5.8 (2.8–11.5) months and 4.5 (2.4–8.0) months, respectively (Kaplan–Meier analysis: P = 0.03). The median survival times in the RF ablation and control groups were 6.1 (4.8–15.2) months and 5.8 (4.2–16.5) months, with no significant difference according to Kaplan–Meier analysis (P = 0.45). In univariate and multivariate analyses, poorer overall survival was associated with advanced age and presence of metastases (P < 0.05). Intraductal RF ablation combined with biliary stent placement for nonresectable malignant

  6. Annual Plasmodium falciparum entomological inoculation rates (EIR) across Africa: literature survey, internet access and review

    PubMed Central

    Hay, Simon I.; Rogers, David J.; Toomer, Jonathan F.; Snow, Robert W.

    2011-01-01

    This paper presents the results of an extensive search of the formal and informal literature on annual Plasmodium falciparum entomological inoculation rates (EIR) across Africa from 1980 onwards. It first describes how the annual EIR data were collated, summarized, neo-referenced and staged for public access on the internet. Problems of data standardization, reporting accuracy and the subsequent publishing of information on the internet follow. The review was conducted primarily to investigate the spatial heterogeneity of malaria exposure in Africa and supports the idea of highly heterogeneous risk at the continental, regional and country levels. The implications for malaria control of the significant spatial (and seasonal) variation in exposure to infected mosquito bites are discussed. PMID:10897348

  7. Portacaval graft patency demonstrated by scintigraphic calculation of portal contribution to hepatic blood flow.

    PubMed

    Martín-Comín, J; Segarra, M I; Pujol, J; Mairal, L; Sans, L; Mora, J; Puchal, R

    1992-11-01

    The case presented refers to a cirrhotic patient with portal hypertension in whom a portacaval graft bypass was surgically implanted. The calculation of the portal contribution to hepatic blood flow helped to demonstrate the patency of the graft. PMID:1424378

  8. Assessment of internal mammary artery and saphenous vein graft patency and flow reserve using transthoracic Doppler echocardiography

    NASA Technical Reports Server (NTRS)

    Chirillo, F.; Bruni, A.; Balestra, G.; Cavallini, C.; Olivari, Z.; Thomas, J. D.; Stritoni, P.

    2001-01-01

    OBJECTIVE: To investigate transthoracic Doppler echocardiography in the identification of coronary artery bypass graft (CABG) flow for assessing graft patency. DESIGN: The initial study group comprised 45 consecutive patients with previous CABG undergoing elective cardiac catheterisation for recurrent ischaemia. The Doppler variables best correlated with angiographic graft patency were then tested prospectively in a further 84 patients (test group). SETTING: Three tertiary referral centres. INTERVENTIONS: Flow velocities in grafts were recorded at rest and during hyperaemia induced by dipyridamole (0.56 mg/kg/4 min), under the guidance of transthoracic colour Doppler flow mapping. Findings on transthoracic Doppler were compared with angiography. MAIN OUTCOME MEASURES: Feasibility of identifying open grafts by Doppler and diagnostic accuracy for Doppler detection of significant (>/= 70%) graft stenosis. RESULTS: In the test group the identification rate for mammary artery grafts was 100%, for saphenous vein grafts to left anterior descending coronary artery 91%, for vein grafts to right coronary artery 96%, and for vein grafts to circumflex artery 90%. Coronary flow reserve (the ratio between peak diastolic velocity under hyperaemia and at baseline) of < 1.9 (95% confidence interval 1.83 to 2.08) had 100% sensitivity, 98% specificity, 87.5% positive predictive value, and 100% negative predictive value for mammary artery graft stenosis. Coronary flow reserve of < 1.6 (95% CI 1.51 to 1.73) had 91% sensitivity, 87% specificity, 85.4% positive predictive value, and 92.3% negative predictive value for significant vein graft stenosis. CONCLUSIONS: Transthoracic Doppler can provide non-invasive assessment of CABG patency.

  9. Patency of Wallstents Placed at the Venous Anastomosis of Dialysis Grafts for Salvage of Angioplasty-Induced Rupture

    SciTech Connect

    Rajan, Dheeraj K.; Clark, Timothy W.I.

    2003-06-15

    Purpose: To retrospectively evaluate the patency of Wallstents placed at the venous anastomosis of polytetraflouroethylene (PTFE) hemodialysis grafts to preserve function following angioplasty-induced rupture. Methods: The charts of all patients who underwent percutaneous angioplasty of functioning hemodialysis PTFE grafts between September 1997 and September 2001 were retrospectively reviewed. A total of 414 angioplasties were performed. Nine cases of rupture at the venousanastomosis managed with stent placement were identified (7 women, 2 men). Two grafts were loop grafts, seven grafts were straight grafts. All stents placed were Wallstents; six stents were 8 x 40 mm, the remaining three were 8 x 20 mm, 8 x 60 mm and 10 x 42mm. Average follow-up was 13 months. Results: Technical and clinical success of stent placement was 100%. The primary patencyrates ({+-}SE) of stents placed at the venous anastomosis were 88% (12%) at 30 days, 63% (17%) at 90 days, 33% (18%) at 180 days and 17% (15%) at 360 days. The secondary patency rates ({+-}SE) were 89% (11%) at 90 days, 76% (15%) at 180 days and 69% (23%) (6 stentspatent) at 360 days. During follow-up, one graft was removed because of infection, one patient died and another was lost to follow-up. A single minor complication of a puncture site hematoma occurred (11%) with no major complications. Conclusions: This small retrospective series suggests that Wallstent placement following angioplasty-induced venous anastomotic rupture is effective for preserving dialyzable flow in hemodialysis grafts. Patency is comparable to that of stents placed for reasons other than rupture.

  10. Microscopic visualization of intravasal spermatozoa is positively associated with patency after bilateral microsurgical vasovasostomy.

    PubMed

    Ramasamy, R; Mata, D A; Jain, L; Perkins, A R; Marks, S H; Lipshultz, L I

    2015-05-01

    We evaluated pre-operative and intraoperative factors associated with successful patency following bilateral microsurgical vasovasostomy (VV). We retrospectively reviewed the charts of 1331 men who underwent bilateral VV by two surgeons between 2006 and 2013. Vasal fluid was examined intraoperatively for gross quality (i.e., clear or opaque and creamy/thick) and for the presence of spermatozoa on microscopy (i.e., whole spermatozoa, sperm fragments, or azoospermia). Post-operative patency was assessed by semen analysis or patient report of conception. Perioperative factors were explored using descriptive statistics and examined in logistic regression models for associations with post-operative patency. The median age at VV was 39 years [interquartile range (IQR): 35-44] and the median obstructive interval (OI) was 7 years (IQR: 4-11). Overall, 1307 patients achieved post-operative patency (98%) while 24 remained obstructed (2%). Among those who became patent, 410 reported conception. After adjustment for potential confounders, only microscopic examination of the intravasal fluid for the presence of spermatozoa (bilateral or unilateral whole spermatozoa vs. sperm parts/azoospermia) at the time of VV was significantly associated with post-operative patency with an odds ratio (OR) of 14.2 (95% CI: 5.8-34.9; p = <1 × 10(-8) ). Identification of bilateral or unilateral sperm fragments vs. azoospermia was also associated with increased odds of post-operative patency with an OR of 3.5 (95% CI: 0.9-13.6; p = 0.08). There was no statistically significant association between age at VV, OI, presence of granuloma, gross fluid quality, or surgeon and post-operative patency after controlling for potential confounders. Identification of whole spermatozoa in the vasal fluid at the time of VV was positively associated with post-operative patency. Our findings stress the need for intraoperative microscopy to aid in post-operative patient counseling. PMID:25914288

  11. Subintimal angioplasty for superficial femoral artery occlusion: poor patency in critical ischaemia.

    PubMed Central

    Smith, B. M.; Stechman, M.; Gibson, M.; Torrie, E. P. H.; Magee, T. R.; Galland, R. B.

    2005-01-01

    INTRODUCTION: Subintimal angioplasty has been proposed for the treatment of long segment occlusive disease and for patients with critical limb ischaemia (CLI) with significant co-morbidity. There is no consensus as to short- and long-term patency. We present our experience with this technique. METHODS: Between 1995 and 2000, 43 consecutive patients (48 limbs) underwent subintimal angioplasty for superficial femoral artery occlusions. Outcome measures were haemodynamic and/or symptomatic patency. RESULTS: Technical success was achieved in 14/17 limbs with CLI (82%) and 30/31 (97%) with intermittent claudication (IC). There were 7 complications (15%), 6 occurring in the claudicant group. The median occlusion length was 10 cm for CLI and 6 cm for IC. Patency at 12 and 36 months, on an intention-to-treat basis, was 69% and 58% for claudicants and 25% and 25% for patients with CLI (P = 0.0005 and P = 0.0044, respectively). Following only technically successful procedures, 12-month patency was 72% (IC) and 31% (CLI) (P = 0.009). Patients with occlusions > or = 10 cm were more likely to re-occlude than those < 10 cm (12-month patency 60% versus 25%;P = 0.037). CONCLUSIONS: In this series, short- and long-term patency in patients with CLI is poor. Subintimal angioplasty in the treatment of CLI should be reserved for those patients not fit for surgical bypass. PMID:16176697

  12. Use of aspirin associates with longer primary patency of hemodialysis grafts.

    PubMed

    Dixon, Bradley S; Beck, Gerald J; Dember, Laura M; Vazquez, Miguel A; Greenberg, Arthur; Delmez, James A; Allon, Michael; Himmelfarb, Jonathan; Hu, Bo; Greene, Tom; Radeva, Milena K; Davidson, Ingemar J; Ikizler, T Alp; Braden, Gregory L; Lawson, Jeffrey H; Cotton, James R; Kusek, John W; Feldman, Harold I

    2011-04-01

    Extended-release dipyridamole plus low-dose aspirin (ERDP/ASA) prolongs primary unassisted graft patency of newly created hemodialysis arteriovenous grafts, but the individual contributions of each component are unknown. Here, we analyzed whether use of aspirin at baseline associated with primary unassisted graft patency among participants in a randomized trial that compared ERDP/ASA and placebo in newly created grafts. We used Cox proportional hazards regression, adjusting for prespecified baseline comorbidities and covariates. Of all participants, 43% reported use of aspirin at baseline; of these, 82% remained on nonstudy aspirin (i.e., excluding ERDP/ASA) at 1 year. After 1 year of follow-up, the incidence of primary unassisted patency among participants using aspirin at baseline was 30% (95% CI: 24 to 35%) and among those not using aspirin was 23% (95% CI: 18 to 27%). Use of aspirin at baseline associated with a dose-dependent prolongation of primary unassisted graft patency that approached statistical significance (adjusted HR, 0.83; 95% CI: 0.68 to 1.01; P=0.06). Use of aspirin at baseline did not associate with prolongation of cumulative graft patency or participant survival. In conclusion, use of aspirin associates with a trend toward longer primary unassisted patency of newly placed hemodialysis grafts similar to that observed for ERDP/ASA. PMID:21415156

  13. Use of Aspirin Associates with Longer Primary Patency of Hemodialysis Grafts

    PubMed Central

    Beck, Gerald J.; Dember, Laura M.; Vazquez, Miguel A.; Greenberg, Arthur; Delmez, James A.; Allon, Michael; Himmelfarb, Jonathan; Hu, Bo; Greene, Tom; Radeva, Milena K.; Davidson, Ingemar J.; Ikizler, T. Alp; Braden, Gregory L.; Lawson, Jeffrey H.; Cotton, James R.; Kusek, John W.; Feldman, Harold I.

    2011-01-01

    Extended-release dipyridamole plus low-dose aspirin (ERDP/ASA) prolongs primary unassisted graft patency of newly created hemodialysis arteriovenous grafts, but the individual contributions of each component are unknown. Here, we analyzed whether use of aspirin at baseline associated with primary unassisted graft patency among participants in a randomized trial that compared ERDP/ASA and placebo in newly created grafts. We used Cox proportional hazards regression, adjusting for prespecified baseline comorbidities and covariates. Of all participants, 43% reported use of aspirin at baseline; of these, 82% remained on nonstudy aspirin (i.e., excluding ERDP/ASA) at 1 year. After 1 year of follow-up, the incidence of primary unassisted patency among participants using aspirin at baseline was 30% (95% CI: 24 to 35%) and among those not using aspirin was 23% (95% CI: 18 to 27%). Use of aspirin at baseline associated with a dose-dependent prolongation of primary unassisted graft patency that approached statistical significance (adjusted HR, 0.83; 95% CI: 0.68 to 1.01; P = 0.06). Use of aspirin at baseline did not associate with prolongation of cumulative graft patency or participant survival. In conclusion, use of aspirin associates with a trend toward longer primary unassisted patency of newly placed hemodialysis grafts similar to that observed for ERDP/ASA. PMID:21415156

  14. High rates of Tuberculosis in patients accessing HAART in rural South Africa

    PubMed Central

    Naidoo, Kogieleum; Karim, Quarraisha Abdool; Bhushan, Ambika; Naidoo, Kasavan; Yende-Zuma, Nonhlanhla; Mchunu, Patricia K; Frohlich, Janet; Karim, Farina; Upfold, Michele; Pharm, BSc; Kocheleff, Paul; Abdool Karim, Salim S

    2014-01-01

    Background The challenge of early Tuberculosis (TB) infection among rural patients accessing HAART in a resource-limited setting with high HIV and TB burden has not been fully quantified. Methods This is a retrospective study nested within a prospective study of 969 patients consecutively initiated onto HAART at the CAPRISA AIDS Treatment programme in rural KwaZulu-Natal between January 2007 and December 2010. Patients were screened for clinical symptoms consistent with TB using a standardized checklist, and routine clinical investigations that included sputum microscopy and chest X-Ray diagnosis. Results Of 969 HIV-infected patients initiated on HAART, 173 (17.9%; 95% CI: 15.5 to 20.4) had active TB at HAART initiation. TB incidence rates were three fold higher in the first 3 months (early incident TB) following HAART initiation (11.5/100 person years (py); 95%CI: 7.1 to 17.5); compared to 4 – 24 months (late incident TB) post HAART initiation (3.2/100 py; 95%CI: 2.2 to 4.5; incidence rate ratio (IRR): 3.6; 95%CI: 2.0 to 6.4; p value <0.001). Immune status of patients at HAART initiation did not impact TB incidence rates in patients with CD4+ counts <50 (5.3/100) and >200 (4.9/100 py; p=0.81); cells/mm3. CD4+ count gains achieved 12 months post HAART initiation were significantly different in patients with early incident TB versus late incident TB; p=0.03. Conclusion Rural HIV treatment programmes in TB endemic settings experience high rates of TB irrespective of immunologic status of patients at HAART initiation, or duration on HAART. PMID:24256629

  15. Should computed tomography angiography supersede invasive coronary angiography for the evaluation of graft patency following coronary artery bypass graft surgery?

    PubMed

    Gabriel, Joseph; Klimach, Stefan; Lang, Peter; Hildick-Smith, David

    2015-08-01

    Invasive coronary angiography (ICA) has long been the established gold standard in assessing graft patency following coronary artery bypass graft (CABG). Over the past decade or so however, improvements in computed tomography angiography (CTA) technology have allowed its emergence as a useful clinical tool in graft assessment. The recent introduction of 64-slice and now 128-slice scanners into widespread distribution, and the development of 320-detector row technology allowing volumetric imaging of the entire heart at single points in time within one cardiac cycle, has increased the potential of CTA to supersede ICA in this capacity. This study sought to examine the evidence surrounding this potential. A best evidence topic was constructed according to a structured protocol. The enquiry: In [patients who have undergone coronary artery bypass graft surgery] is [computed tomography angiography or invasive coronary angiography] superior in terms of [graft patency assessment, stenosis detection, radiation exposure and complication rate]? Four hundred and twenty-four articles were identified from the search strategy. Four additional articles were identified from references of key articles. Seventeen articles selected as best evidence were tabulated. The reliability of CTA as a tool in the detection of graft patency and stenosis has continued to improve with each successive generation of multislice technology. The latest 64- and 128-slice CTA techniques are able to detect graft patency and stenosis with very high sensitivities and specificities comparable with ICA, while remaining non-invasive procedures associated with fewer complications (ICA carries a 0.08% risk of myocardial infarction and 0.7% risk of minor complications in clinically stable patients). Present limitations of the technology include the accurate visualization of distal anastomoses and clip artefacts. In addition, the capacity of diagnostic ICA to be combined simultaneously with percutaneous coronary

  16. Measuring, Rating, Supporting, and Strengthening Open Access Scholarly Publishing in Brazil

    ERIC Educational Resources Information Center

    Neto, Silvio Carvalho; Willinsky, John; Alperin, Juan Pablo

    2016-01-01

    This study assesses the extent and nature of open access scholarly publishing in Brazil, one of the world's leaders in providing universal access to its research and scholarship. It utilizes Brazil's Qualis journal evaluation system, along with other relevant data bases to address the association between scholarly quality and open access in the…

  17. Decrease in Suicide Rates after a Change of Policy Reducing Access to Firearms in Adolescents: A Naturalistic Epidemiological Study

    ERIC Educational Resources Information Center

    Lubin, Gad; Werbeloff, Nomi; Halperin, Demian; Shmushkevitch, Mordechai; Weiser, Mark; Knobler, Haim Y.

    2010-01-01

    The use of firearms is a common means of suicide. We examined the effect of a policy change in the Israeli Defense Forces reducing adolescents' access to firearms on rates of suicide. Following the policy change, suicide rates decreased significantly by 40%. Most of this decrease was due to decrease in suicide using firearms over the weekend.…

  18. Prosthetic graft interposition of the brachiocephalic veins or superior vena cava combined with resection of malignant tumours: graft patency and risk factors for graft occlusion

    PubMed Central

    Lee, Geun Dong; Choi, Se Hoon; Kim, Yong-Hee; Kim, Dong Kwan; Park, Seung-Il

    2016-01-01

    Background We aimed to assess graft patency in patients undergoing prosthetic graft interposition of the brachiocephalic veins (BCVs) or the superior vena cava (SVC) combined with resection of malignant tumours. Methods A retrospective analysis was conducted on 16 patients who underwent prosthetic graft interposition of the BCVs or the SVC between 1998 and 2012. Results Among a total of 20 grafts in 16 patients (unilateral graft interposition in 12, bilateral graft interposition in 4), 8 grafts were occluded in 8 patients. Overall graft patency rate was 64.6%, 42.4% at the 2- and 5-year follow-up. Graft patency rate of the left BCV was significantly lower than that of the right BCV or the SVC (2-year patency, 38.1% vs. 81.8%, P=0.024). In univariate analysis, the superior anastomosis site [left BCV vs. right BCV; hazard ratio (HR) =2.312; 95% confidence interval (CI), 1.015–5.265; P=0.046], the inferior anastomosis site (right atrial appendage vs. SVC; HR =2.409; 95% CI, 1.124–5.161; P=0.024), and interruption of warfarin (HR =5.015; 95% CI, 1.106–22.734; P=0.037) were significant risk factors for graft occlusion. Graft occlusive symptoms were identified in 4 patients who underwent unilateral graft interposition. Conclusions Prosthetic graft interposition between the left BCV and the right atrial appendage resulted in a significant rate of graft occlusion. Prosthetic graft interposition of the bilateral BCVs and long-term warfarin therapy may be necessary to prevent graft occlusive symptoms. PMID:26904213

  19. Endoscopic Versus "No-Touch" Saphenous Vein Harvesting for Coronary Artery Bypass Grafting: A Trade-Off Between Wound Healing and Graft Patency.

    PubMed

    Kopjar, Tomislav; Dashwood, Michael R

    2016-02-01

    The advantage in terms of wound infection, wound healing, and scarring has resulted in the recent adoption of endoscopic vein harvesting (EVH) as a standard of care for coronary artery bypass grafting in some centers. However, concerns regarding the quality of these grafts have been raised after recent evidence of decreased graft patency, increased reoperation rate, and myocardial infarct, problems that are associated with vascular trauma caused when using this technique. Simultaneously, an atraumatic, "no-touch" technique for harvesting the saphenous vein was developed producing grafts with improved patency comparable to the internal thoracic artery. However, wound complications remain a problem using this technique. This review outlines the need to consider the poor graft quality that may result from EVH and raises the question what is likely to be the "best practice principle" in saphenous vein harvesting? PMID:25972395

  20. Intraarterial 9-beta-methyl carbacyclin improves canine polytetrafluoroethylene graft patency

    SciTech Connect

    Dacey, L.J.; Hees, P.S.; Cronenwett, J.L.

    1988-07-01

    This study examined the effect of 9-beta-methyl carbacyclin, a synthetic, stable prostacyclin analog, on canine polytetrafluoroethylene (PTFE) graft patency. Twenty-five dogs had 4 mm x 7 cm PTFE grafts implanted bilaterally into the femoral arteries. A subcutaneous infusion pump was used to deliver either saline solution (control) or 9-beta-methyl carbacyclin (Ciprostine) at 100 (CARB-100) or 200 ng/kg/min (CARB-200) through a femoral artery branch just proximal to one of the femoral grafts, with the contralateral graft serving as a noninfused control. Graft-platelet deposition (with /sup 111/In-labeled platelets) was measured between the fifth and seventh days, with patency determined on the seventh day. Dogs were classified as aggregators (AGG (+)) if the preoperative epinephrine-enhanced sodium arachidonate platelet aggregation was greater than 20%. CARB-200 infusion significantly improved ipsilateral graft patency (80%) compared with noninfused grafts (50%, p less than 0.05), or grafts in control and CARB-100 dogs (43%, p less than 0.05). Anastomotic platelet deposition was decreased bilaterally in CARB-200 dogs by 45% to 59% compared with CARB-100 and control dogs (p less than 0.05). With the exception of grafts infused with CARB-200, AGG (+) dogs had significantly lower graft patency (26%) than nonaggregator AGG (-) dogs (71%, p less than 0.01). CARB-200 infusion significantly improved graft patency in AGG (+) dogs (71%), compared with control and CARB-100-infused grafts (19%, p less than 0.025). Intra-arterial 9-beta-methyl carbacyclin improved early PTFE graft patency and inhibited platelet deposition in a severe canine model, independent of baseline platelet aggregation status, which also had an important effect on graft patency.

  1. From dose rate to websites: making measurements accessible, understandable and helpful to the lay public.

    PubMed

    Zähringer, M; Luff, R; Schiesewitz, M; Burbeck, S; Högg, R

    2014-08-01

    The key role of public information in emergency preparedness has more recently been corroborated by the experience of the Great Eastern Japan Earthquake and Tsunami and the subsequent nuclear accident at the Fukushima NPP. Information should meet quality criteria such as openness, accessibility and authenticity. Existing information portals of radiation monitoring networks were frequently used even in Europe, although there was no imminent radiation risk. BfS responded by increasing the polling frequency, publishing current data not validated, refurbishing the website of the BfS 'odlinfo.bfs.de' and adding explanatory text. Public feedback served as a valuable input for improving the site's design. Additional services were implemented for developers of smart phone apps. Websites similar to 'ODLInfo' are available both on European and international levels. NGOs and grass root projects established platforms for uploading and visualising private dose rate measurements in Japan after 11 March 2011. The BfS site is compared with other platforms. Government information has to compete with non-official sources. Options on information strategies are discussed. PMID:24993007

  2. Improving access to emergency contraception under the Scottish Sexual Health Strategy: can rates of unintended pregnancy be reduced?

    PubMed

    McGowan, James G

    2013-09-01

    Unintended pregnancy is a global sexual health problem. Outcomes of unintended pregnancy include unwanted childbirth and abortion, which may be associated with negative physical and psychosocial health implications for women. In Scotland, the Scottish Sexual Health Strategy has the stated goal of improving the sexual health of the people of Scotland. One aim of the Strategy is to reduce rates of unintended pregnancy and one policy designed to achieve this is 'widening access to emergency contraception'. This paper examines the success of this policy with reference to the implicit link it makes between expanding access to emergency contraception and increasing its effective use, aiming thereby to reduce rates of unintended pregnancy. Since there is evidence that previous policies and strategies expanding access to emergency contraception have failed to reduce such rates, alternative approaches to achieve a reduction in unintended pregnancies are discussed. PMID:24007249

  3. Occluded Brescia-Cimino Hemodialysis Fistulas: Endovascular Treatment with Both Brachial Arterial and Venous Access Using the Pull-Through Technique

    SciTech Connect

    Miyayama, Shiro Matsui, Osamu; Taki, Keiichi; Minami, Tetsuya; Shinmura, Rieko; Ito, Chiharu; Takamatsu, Shigeyuki; Kobayashi, Miki; Ushiogi, Yashuyuki

    2005-12-15

    We retrospectively evaluated the usefulness of both arterial and venous access with the pull-through technique in endovascular treatment of totally occluded Brescia-Cimino fistulas. We treated 26 patients (17 men, 9 women; age range 43-82 years, mean age 66 years) with occluded Brescia-Cimino fistulas. First, the occluded segment was traversed from the antegrade brachial arterial access using a microcatheter-guidewire system. Second, the vein was retrogradely punctured after confirmation of all diseased segments, and a 0.014- or 0.016-inch guidewire was pulled through the venous access when the occluded segment was long. All interventions including thrombolysis, thromboaspiration, angioplasty, and stent placement were performed via the venous access. The occlusion was successfully crossed via the brachial arterial access in 23 patients (88%). In 2 patients it was done from the venous approach. In the remaining patient it was not possible to traverse the occluded segment. The pull-through technique was successful in all 19 attempts. Clinical success was achieved in 96%, the primary patency rates at 6, 12, and 18 months were 83%, 78%, and 69%, the primary assisted patency rates were 92%, 92%, and 72%, and the secondary patency rates were 92%, 92%, and 92%, respectively. Minor complications in 5 patients included venous perforation in 2 (8%), venous rupture in 1 (4%), and regional hematoma in 2 (8%). Our study suggests that endovascular treatments with both arterial and venous access using the pull-through technique are highly effective in restoring function in totally occluded Brescia-Cimino fistulas.

  4. Efficacy of Doppler Ultrasonography for Assessment of Transjugular Intrahepatic Portosystemic Shunt Patency

    SciTech Connect

    Kimura, Masashi; Sato, Morio; Kawai, Nobuyuki; Tanaka, Kayo; Sonomura, Tetsuo; Shioyama, Kazushi; Kishi, Yasukazu; Terada, Masaki; Yamada, Ryusaku

    1996-11-15

    Purpose: To assess the efficacy of Doppler ultrasonography (US) as a noninvasive method for monitoring patency of the transjugular intrahepatic portosystemic shunt (TIPS). Methods: Twenty-nine patients who had received TIPS for bleeding esophagogastric varices and/or refractory ascites with portal hypertension underwent Doppler US studies within 2 weeks after TIPS. Further studies were performed in 15 of them at 6 months, in 9 at 1 year, and in 4 at 2 years for a total of 57 US studies. The US findings were compared with the angiographic findings obtained at the same time. Results: In 45 of the 57 studies, shunt patency was found by Doppler US, correlating to 44 patencies and one occlusion on angiography. Doppler signal in the shunt could not be detected in 12 studies resulting in the diagnosis of shunt occlusion. This correlated with angiographic occlusion in 8 studies and patency in the remaining 4. All angiographically patent shunts that were occluded by Doppler US had various degrees of stenosis. A number of technical factors were found to be responsible for Doppler US false-positive or false-negative diagnoses, some related to the type of stent used. The Doppler US sensitivity was therefore 92%, the specificity 89%. Conclusion: Doppler US is a reliable noninvasive method to evaluate patency of TIPS.

  5. 47 CFR 51.911 - Access reciprocal compensation rates for competitive LECs.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... competitive LECs. 51.911 Section 51.911 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES (CONTINUED) INTERCONNECTION Transitional Access Service Pricing § 51.911 Access... Competitive LECs operating in an area served by a Price Cap Carrier, no such Competitive LEC may increase...

  6. Blockade of tubal patency following transcervical administration of polidocanol foam: initial studies in rhesus macaques

    PubMed Central

    Jensen, Jeffrey T; Hanna, Carol; Yao, Shan; Micks, Elizabeth; Edelman, Alison; Holden, Lindsay; Slayden, Ov D

    2014-01-01

    Objective To demonstrate the feasibility of polidocanol foam (PF) as a nonsurgical method of female permanent contraception using a nonhuman primate model. Study Design Four groups of adult female rhesus macaques underwent either transcervical treatment with 5% PF directly into the uterine cavity, treatment with inert (methylcellulose, MF) foam or no treatment followed by removal of the reproductive tract for histologic evaluation. Untreated animals were included in Group 1 (n= 3). Group 2 animals (n= 4) were treated once with MF. Group 3 (n=7) received a single, and Group 4 (n= 5) received multiple monthly treatments with PF; in these 2 groups, baseline tubal patency was assessed either laparoscopically by chromopertubation (CP) or by hysterosalpingography. Results Group 1 (untreated) and Group 2 (MF) animals had normal tubal histology. In contrast, Group 3 and 4 females treated with PF showed evidence of tubal damage. In Group 4, bilateral tubal blockade was noted on CP after two (n=2) or three (n=3) treatments. Histologic analysis confirmed complete tubal occlusion (loss of epithelium, fibrosis) in 3 of these animals and 1 showed significant tubal damage localized to the intramural segment. Nontarget (cervix, vagina, endometrium, ovary) reproductive tissues were unaffected. While similar tubal changes were observed after a single treatment (Group 3), endometrial hemorrhage was also noted Conclusion PF is a promising candidate agent for nonsurgical permanent female contraception. The histologic features of PF occlusion are confined to the intramural portion of the tube. Implications This study in rhesus macaques supports further development of transcervical administration of polidocanol foam as a nonsurgical approach to permanent contraception. A nonsurgical method could reduce risks and costs associated with surgical female sterilization, and increase access to permanent contraception. PMID:24560476

  7. Access-Related Venous Stenoses and Occlusions: Treatment with Percutaneous Transluminal Angioplasty and Dacron-Covered Stents

    SciTech Connect

    Farber, Alexander; Barbey, Mark-Michael; Grunert, Jens-Holger; Gmelin, Ekkechardt

    1999-05-15

    Purpose: To determine the effectiveness of using Dacron-covered stents to treat access-related venous stenoses and occlusions. Methods: Twenty-two Dacron-covered stents were placed in 20 patients: in the basilic or axillary vein (n = 2), cephalic vein (n = 3), subclavian vein (n = 5), and at the venous anastomosis of the polytetrafluoroethylene (PTFE) implant graft (n 10). Results: Initial technical success was 100%. The cumulative primary and secondary patency rates were 57% and 83% at 6 months, 29% and 64% at 12 months, and 29% and 53% at 18 months. A statistically significant difference in the stent patency was revealed by comparing the patients with stents in the subclavian vein and patients with upper arm stents. The secondary patency rates of the upper arm stents were 73% after 6, 12, and 18 months. Conclusions: Percutaneous placement of Dacron-covered stents is a safe and effective procedure for salvage of a dialysis fistula. First results are promising, with a tendency to prolongation of the time interval between reinterventions.

  8. A comparison of Frequency Domain Multiple Access (FDMA) and Time Domain Multiple Access (TDMA) approaches to satellite service for low data rate Earth stations

    NASA Technical Reports Server (NTRS)

    Stevens, G.

    1983-01-01

    A technological and economic assessment is made of providing low data rate service to small earth stations by satellite at Ka-band. Various Frequency Domain Multiple Access (FDMA) and Time Domain Multiple Access (TDMA) scenarios are examined and compared on the basis of cost to the end user. Very small stations (1 to 2 meters in diameter) are found not to be viable alternatives to available terrestrial services. However, medium size (3 to 5 meters) earth stations appear to be very competitive if a minimum throughput of about 1.5 Mbs is maintained. This constrains the use of such terminals to large users and shared use by smaller users. No advantage was found to the use of FDMA. TDMA had a slight advantage from a total system viewpoint and a very significant advantage in the space segment (about 1/3 the required payload weight for an equivalent capacity).

  9. Rate Setting Policies: Ensuring Access and Improving Quality. Issues Meeting Proceedings (Washington, D.C., November 28-29, 2000).

    ERIC Educational Resources Information Center

    Schock, Lisa; Daugherty, Jane

    In November 2000, the Child Care Bureau, Administration for Children and Families, U.S. Department of Health and Human Services, convened an Issues Meeting focused on Rate-Setting Policies: Ensuring Access and Improving Quality. The meeting brought together state child care administrators and others for discussions on conducting effective market…

  10. [Ways to improve patency of the femoral-popliteal-crural bypass grafts].

    PubMed

    Sazhinov, A P; Lukinskiĭ, A V; Chupin, A V

    2014-01-01

    Chronic obliterating diseases of lower-limb arteries account for more than 20% of all manifestations of cardiovascular pathology. A surgical method of treatment for this pathology remains most effective. The types of operations below the inguinal fold currently used are as follows: bypass grafting, endarterectomy, and angioplasty. The vein is the material of choice and if it is not easily available allografts may be used. Differing elastic properties of the artery and prosthesis lead to progression of the neointima thus negatively affecting patency of bypass grafts. This article describes venous bypass grafts, their efficacy, methods of improving patency of allografts, as well as variants of combined operations. PMID:24722032

  11. Accessibility compliance rates of consumer-oriented Canadian health care Web sites.

    PubMed

    O'Grady, Laura

    2005-12-01

    Vast amounts of consumer-based health care information are widely available on the World Wide Web. However, for some this material is inaccessible due to reliance on specialized computer equipment or software known as assistive technology. These tools, designed for people with sensory, physical, or learning disabilities, act as a median to interpret Web pages in accessible ways. Unfortunately, many websites, including those with health-related content are not designed to accommodate this equipment. No research has yet been published examining the extent of this problem in Canadian consumer-oriented health care sites. The purpose of this study was to investigate the percentage of accessible consumer-based health care websites of Canadian origin. A listing of such sites was randomly sampled for study inclusion. Each was assessed for accessibility based on the World Wide Web Consortium (W3C) Web Accessibility Initiative (WAI) Web Content Accessibility Guidelines (WCAG) 1.0 using the validation software Bobby. The results indicated that only about 40% of pages investigated were free of errors in accordance with WCAG 1.0 Priority 1 level. Websites should be constructed in compliance with these standards to better accommodate those using assistive devices. PMID:16531355

  12. The Lateral Position Improved Airway Patency in Anesthetized Patient With Burn-Induced Cervico-Mento-Sternal Scar Contracture

    PubMed Central

    Arai, Young-Chang P.; Kawanishi, Jun; Sakakima, Yoshikazu; Ohmoto, Koichi; Ito, Akihiro; Maruyama, Yuki; Ikemoto, Tatsunori

    2016-01-01

    A 78-year-old woman with burn-induced cervico-mento-sternal scar contracture was scheduled for laparoscopic cholecystectomy. During inhalational induction of sevoflurane, her airway patency deteriorated. The right lateral position and assist ventilation using a breathing bag dramatically improved her airway patency. PMID:27252906

  13. Comparison of Efficacy of Side to Side Versus End to Side Arteriovenous Fistulae Formation in Chronic Renal Failure as a Permanent Hemodialysis Access

    PubMed Central

    Mozaffar, Mohammad; Fallah, Mahtab; Lotfollahzadeh, Saran; Sobhiyeh, Mohammad Reza; Gholizadeh, Barmak; Jabbehdari, Sayena; Mahdi, Zeinab

    2013-01-01

    Background In candidate patients for permanent hemodialysis or dialysis on a regular basis, an appropriate vascular access has great importance. The best permanent access is AVF (arterio venous fistula). Use of a technique to create AVF with better patency seems to be logical. Objectives The present study aimed to compare the efficacy rate of AVFs using two different anastomosis methods; Side to Side (STS) versus End to Side (ETS) and to determine whether the different approaches render any preferences or complications. Patients and Methods Sixty end stage renal disease (ESRD) patients were included in this clinical trial in two assigned groups of 30 patients. In one group end to side method to create AVF was used while in the other group Side to Side technique was applied for access in surgery. Both groups were followed for duration of 6 months to assess patency. For evaluating the quantitive variables, t-test was used while qualitative variables were measured using the chi-square and Fisher`s exact tests. Results In the 6 months duration, 6 patients (20%) in the STS (side to side) group and 5 patients (16.6%) in the ETS (end to side) group experienced a non-functional AVF. In the ETS group the failure was generally a result of thrombosed access while in the STS group, 4 out of 6 patients with complications, experienced thrombosis while the other 2 patients had venous hypertension. The total failure rate was 18.3% and during the 6 months of follow up no significant difference was detected in the efficacy rate. Nevertheless, in case of longer follow ups, different outcomes could be seen. Conclusions This study demonstrated that there was no significant statistical difference between the functional patency rates of fistulae placed by STS or ETS methods. PMID:24282794

  14. An energy-efficient rate adaptive media access protocol (RA-MAC) for long-lived sensor networks.

    PubMed

    Hu, Wen; Chen, Quanjun; Corke, Peter; O'Rourke, Damien

    2010-01-01

    We introduce an energy-efficient Rate Adaptive Media Access Control (RA-MAC) algorithm for long-lived Wireless Sensor Networks (WSNs). Previous research shows that the dynamic and lossy nature of wireless communications is one of the major challenges to reliable data delivery in WSNs. RA-MAC achieves high link reliability in such situations by dynamically trading off data rate for channel gain. The extra gain that can be achieved reduces the packet loss rate which contributes to reduced energy expenditure through a reduced numbers of retransmissions. We achieve this at the expense of raw bit rate which generally far exceeds the application's link requirement. To minimize communication energy consumption, RA-MAC selects the optimal data rate based on the estimated link quality at each data rate and an analytical model of the energy consumption. Our model shows how the selected data rate depends on different channel conditions in order to minimize energy consumption. We have implemented RA-MAC in TinyOS for an off-the-shelf sensor platform (the TinyNode) on top of a state-of-the-art WSN Media Access Control Protocol, SCP-MAC, and evaluated its performance by comparing our implementation with the original SCP-MAC using both simulation and experiment. PMID:22219675

  15. An Energy-efficient Rate Adaptive Media Access Protocol (RA-MAC) for Long-lived Sensor Networks

    PubMed Central

    Hu, Wen; Chen, Quanjun; Corke, Peter; O’Rourke, Damien

    2010-01-01

    We introduce an energy-efficient Rate Adaptive Media Access Control (RA-MAC) algorithm for long-lived Wireless Sensor Networks (WSNs). Previous research shows that the dynamic and lossy nature of wireless communications is one of the major challenges to reliable data delivery in WSNs. RA-MAC achieves high link reliability in such situations by dynamically trading off data rate for channel gain. The extra gain that can be achieved reduces the packet loss rate which contributes to reduced energy expenditure through a reduced numbers of retransmissions. We achieve this at the expense of raw bit rate which generally far exceeds the application’s link requirement. To minimize communication energy consumption, RA-MAC selects the optimal data rate based on the estimated link quality at each data rate and an analytical model of the energy consumption. Our model shows how the selected data rate depends on different channel conditions in order to minimize energy consumption. We have implemented RA-MAC in TinyOS for an off-the-shelf sensor platform (the TinyNode) on top of a state-of-the-art WSN Media Access Control Protocol, SCP-MAC, and evaluated its performance by comparing our implementation with the original SCP-MAC using both simulation and experiment. PMID:22219675

  16. A simple, effective media access protocol system for integrated, high data rate networks

    NASA Technical Reports Server (NTRS)

    Foudriat, E. C.; Maly, K.; Overstreet, C. M.; Khanna, S.; Zhang, L.

    1992-01-01

    The operation and performance of a dual media access protocol for integrated, gigabit networks are described. Unlike other dual protocols, each protocol supports a different class of traffic. The Carrier Sensed Multiple Access-Ring Network (CSMA/RN) protocol and the Circulating Reservation Packet (CRP) protocol support asynchronous and synchronous traffic, respectively. The two protocols operate with minimal impact upon each other. Performance information demonstrates that they support a complete range of integrated traffic loads, do not require call setup/termination or a special node for synchronous traffic control, and provide effective pre-use and recovery. The CRP also provides guaranteed access and fairness control for the asynchronous system. The paper demonstrates that the CSMA-CRP system fulfills many of the requirements for gigabit LAN-MAN networks most effectively and simply. To accomplish this, CSMA-CRP features are compared against similar ring and bus systems, such as Cambridge Fast Ring, Metaring, Cyclic Reservation Multiple Access, and Distributed Dual Queue Data Bus (DQDB).

  17. A Meta-analysis of randomized clinical trials assessing hemodialysis access thrombosis based on access flow monitoring: Where do we stand?

    PubMed Central

    Muchayi, Timothy; Salman, Loay; Tamariz, Leonardo J; Asif, Arif; Rizvi, Abid; Lenz, Oliver; Vazquez-Padron, Roberto I.; Tabbara, Marwan; Contreras, Gabriel

    2015-01-01

    The National Kidney Foundation Kidney Disease Outcomes Quality Initiative recommends the routine use of hemodialysis arteriovenous (AV) access surveillance to detect hemodynamically significant stenoses and appropriately correct them to reduce the incidence of thrombosis and to improve accesses patency rates. Access blood flow monitoring is considered as one of the preferred surveillance method for both AV fistulas (AVF) and AV grafts (AVG); however, published studies have reported conflicting results of its utility that led healthcare professionals to doubt the benefits of this surveillance method. We performed a meta-analysis of the published randomized controlled trials (RCTs) of AV access surveillance using access blood flow monitoring. Our hypothesis was that access blood flow monitoring lowers the risk of AV access thrombosis and that the outcome differs between AVF and AVG. The estimated overall pooled risk ratio (RR) of thrombosis was 0.87 (95% confidence interval [CI], 0.67 to 1.13) favoring access blood flow monitoring. The pooled RR of thrombosis were 0.64 (95% CI, 0.41 to 1.01) and 1.06 (95% CI, 0.77 to 1.46) in the subgroups of only AVF and only AVG, respectively. Our results added to the uncertainty of access blood flow monitoring as a surveillance method of hemodialysis accesses. PMID:25644548

  18. High data rate modem simulation for the space station multiple-access communications system

    NASA Technical Reports Server (NTRS)

    Horan, Stephen

    1987-01-01

    The communications system for the space station will require a space based multiple access component to provide communications between the space based program elements and the station. A study was undertaken to investigate two of the concerns of this multiple access system, namely, the issues related to the frequency spectrum utilization and the possibilities for higher order (than QPSK) modulation schemes for use in possible modulators and demodulators (modems). As a result of the investigation, many key questions about the frequency spectrum utilization were raised. At this point, frequency spectrum utilization is seen as an area requiring further work. Simulations were conducted using a computer aided communications system design package to provide a straw man modem structure to be used for both QPSK and 8-PSK channels.

  19. Preserved saphenous vein allografts for vascular access.

    PubMed

    Piccone, V A; Sika, J; Ahmed, N; LeVeen, H H; DiScala, V

    1978-09-01

    Preserved venous allografts were used as an alternate access procedure in 70 patients receiving dialysis during a three year period. The clinical experience with allograft fistulas revealed an extremely high initial patency rate; absence of infection postoperatively and during three years of dialysis; suitability for dialysis a week after implantation, thus greatly obviating the need for Silastic shunts; a low long term thrombosis rate and the weakly antigenic allograft veins produced no accelerated rejection of subsequently transplanted kidneys. Surviving patients average 172 dialysis treatments per allograft. Allograft fistulas constituted 45 per cent of the last 100 vascular procedures, an indication of the extent of usage. Microscopic examination of grafts retrieved from patients who died during the late follow-up period demonstrated that structural components of the wall of the vein were still identifiable. Allograft venous fistulas offer dependable, safe vascular access, especially in the infection prone patient with diabetes who is receiving dialysis treatment. The clinical results of allograft fistulas suggests a major role for this technique in vascular access operations. PMID:684591

  20. Closed Catheter Access System Implementation in Reducing the Bloodstream Infection Rate in Low Birth Weight Preterm Infants

    PubMed Central

    Rundjan, Lily; Rohsiswatmo, Rinawati; Paramita, Tiara Nien; Oeswadi, Chrissela Anindita

    2015-01-01

    Background: Bloodstream infection (BSI) is one of the significant causes of morbidity and mortality encountered in a neonatal intensive care unit, especially in developing countries. Despite the implementation of infection control practices, such as strict hand hygiene, the BSI rate in our hospital is still high. The use of a closed catheter access system to reduce BSI related to intravascular catheter has hitherto never been evaluated in our hospital. Objective: To determine the effects of closed catheter access system implementation in reducing the BSI rate in preterm neonates with low birth weight. Methods: Randomized clinical trial was conducted on 60 low birth weight preterm infants hospitalized in the neonatal unit at Cipto Mangunkusumo Hospital, Jakarta, Indonesia from June to September 2013. Randomized subjects either received a closed or non-closed catheter access system. Subjects were monitored for 2 weeks for the development of BSI based on clinical signs, abnormal infection parameters, and blood culture. Results: Closed catheter access system implementation gave a protective effect toward the occurrence of culture-proven BSI (relative risk 0.095, 95% CI 0.011–0.85, p = 0.026). Risk of culture-proven BSI in the control group was 10.545 (95% CI 1.227–90.662, p = 0.026). BSI occurred in 75% of neonates without risk factors of infection in the control group compared to none in the study group. Conclusion: The use of a closed catheter access system reduced the BSI in low birth weight preterm infants. Choosing the right device design, proper disinfection of device, and appropriate frequency of connector change should be done simultaneously. PMID:25853110

  1. Tissue-engineered vascular grafts: autologous off-the-shelf vascular access?

    PubMed

    Manson, Roberto J; Unger, Joshua M; Ali, Aamna; Gage, Shawn M; Lawson, Jeffrey H

    2012-11-01

    Dialysis grafts have provided reliable access for millions of patients in need of renal replacement therapy. However, regardless of the material used for artificial dialysis grafts their mean patency remains generally poor and infection rates are greater than native arteriovenous fistulas. The need for superior alternatives to conventional synthetic materials used for vascular access has been an area of investigation for more than 25 years and recently there has been a great deal of progress in the field of tissue-engineered vascular grafts. Many of these technologies are either commercially available or are now entering early phases of clinical trials. This review briefly covers the history, potential advantages, and disadvantages of these technologies, which are likely to create an impact in the field of vascular access surgery. PMID:23217339

  2. Beyond Access: An Analysis of the Influence of the E-Rate Program in Bridging the Digital Divide in American Schools

    ERIC Educational Resources Information Center

    Park, Euna; Sinha, Hansa; Chong, Jing

    2007-01-01

    E-Rate is a U.S. federal funding program for providing discounts for telecommunications, Internet access and internal networking costs for schools and libraries to ensure access equity across poor and rich, rural, urban and suburban areas, and highly served and underserved areas. This paper examines the impact of the E-Rate program on social…

  3. What is the best training for vascular access surgery?

    PubMed

    Lazarides, Miltos K; Georgiadis, George S; Georgakarakos, Efstratios I

    2015-01-01

    Questions have been raised whether there is a lack of appropriate training in access creation and maintenance, and if training juniors in arteriovenous (AV) fistulas may affect the outcome. A survey was undertaken to study "experts" opinion in access training using a closed questionnaire. The majority of "experts" consented that there is a lack of appropriate training in access creation and maintenance in a great extent, although they located the main deficit regarding access training in the preoperative planning and decision making. Regarding the second question, a literature search revealed only four studies, comparing the outcomes of AV fistulas created either by consultant surgeons or trainees. A meta-analysis performed revealed that 1-year patency rate was not statistically significant different among access procedures created either by consultants or trainees. Access surgery shares the same basic principles with vascular surgery and provides a valuable workload for the trainees and is a necessity to become a building component in all "core" vascular curricula; the required skills can be acquired with the trainees operating independently simple cases, as the latter is not leading to suboptimal outcomes. PMID:25684580

  4. The Impact of Apical Patency in the Success of Endodontic Treatment of Necrotic Teeth with Apical Periodontitis: A Brief Review

    PubMed Central

    Machado, Ricardo; Ferrari, Carlos Henrique; Back, Eduardo; Comparin, Daniel; Tomazinho, Luiz Fernando; Vansan, Luiz Pascoal

    2016-01-01

    Accumulation of soft tissue or dentinal remnants in the apical region is a common event that can cause blockage of root canals. This event can be avoided if apical patency is performed during the root canal shaping procedures. However, there is no consensus on the role of apical patency in relation to the success of endodontic treatment of necrotic teeth with apical periodontitis. Therefore, the purpose of this paper was to conduct a brief review on the role of apical patency in guaranteeing the success of endodontic treatments of necrotic teeth with apical periodontitis considering two other key points; the root canal anatomy and microbiology. PMID:26843880

  5. Optimum rate Reed-Solomon codes for frequency-hopped spread-spectrum multiple-access communication systems

    NASA Astrophysics Data System (ADS)

    Kim, Sang W.; Stark, Wayne

    1989-02-01

    The authors consider a multiple-access frequency-hopped spread-spectrum communication system with Reed-Solomon codes. The performance measures of interest are an achieveable region and the channel throughput. The achieveable rate region is the set of all pairs of code rate and number of users for which communication is possible with error probability below a fixed value. The throughput measures the expected number of successful codeword transmissions per unit bandwidth. Two models of interference are considered. For these two models, the authors determine the optimal number of users for a given bandwidth and the optimal rate Reed-Solomon code that maximize the throughput. They also determine the achieveable region for these models.

  6. Robust rate-adaptive hybrid ARQ scheme for frequency-hopped spread-spectrum multiple-access communication systems

    NASA Astrophysics Data System (ADS)

    Bigloo, Amir M. Y.; Gulliver, T. Aaron; Wang, Q.; Bhargava, Vijay K.

    1994-06-01

    This paper considers the application of rate-adaptive coding (RAC) to a spread spectrum multiple access (SSMA) communication system. Specifically, RAC using a variable rate Reed-Solomon (RS) code with a single decoder is applied to frequency-hopped SSMA. We show that this combination can accommodate a larger number of users compared to that with conventional fixed-rate coding. This increase is a result of a reduction in the channel interference from other users. The penalty for this improvement in most cases is a slight increase in the delay (composed of propagation and decoding delay). The throughput and the undetected error probability for a Q-ary symmetric channel are analyzed, and performance results are presented.

  7. Midterm Results Following Percutaneous Rotational Thrombectomy for Acute Thrombotic Occlusions of Prosthetic Arteriovenous Access Grafts.

    PubMed

    Karatepe, Celalettin; Aldemir, Mustafa; Çınar, Bayer; Önalan, Akif; Işsever, Halim; Goksel, Onur S

    2015-07-01

    Patent vascular access is critical for patients on regular hemodialysis. Prosthetic grafts are good alternatives when the superficial venous system is of poor quality. However, thrombosis is one of the main drawbacks of synthetic grafts, with reports of 59% to 90% patency rates for 1 year. In cases of thrombotic occlusion of prosthetic arteriovenous fistula grafts, percutaneous mechanical thrombectomy has recently gained clinical popularity as a potential alternative to surgical thrombectomy or pharmacologic thrombolysis. We reviewed our preliminary results from 30 percutaneous rotational thrombectomies performed in a total of 22 patients in the setting of acute dialysis-access prosthetic graft occlusion of the upper extremity. Among the 30 cases of acute occlusion of the arteriovenous graft, immediate success with angiographic flow restoration was observed in all patients except for 2 patients (both females; 6%), with de novo occlusion where reocclusion occurred within 12 hours despite apparent immediate angiographic patency. The mean duration between the initial presentation with acute arteriovenous graft occlusion and the thrombectomy procedure was 27.4 ± 12.4 hours. The mean duration of graft patency was 10.45 ± 0.6 months. A total of 75% of the arteriovenous grafts were patent at the end of 12 months of follow-up. Female gender, diabetes mellitus, and diagnosis to intervention interval were reviewed for midterm graft failure, and the presence of diabetes mellitus yielded significance (P < 0.05). Percutaneous techniques play important roles in the treatment of failed or failing arteriovenous fistulae and grafts. Ongoing analysis of outcomes of both percutaneous and surgical intervention is necessary to continue to identify optimum treatment algorithms. PMID:26595502

  8. Value of middle ear inflation as a diagnostic indicator of eustachian tube patency.

    PubMed

    Luntz, M; Sadé, J

    1990-02-01

    The value of tubal inflation as a diagnostic procedure for Eustachian tube patency and function is controversial. In an attempt to assess the diagnostic value of air douche in atelectatic ears, 49 such ears of 40 patients were politzerized. The procedure was successful in 45 ears. However, of the four unsuccessful cases, two of the patients were able to autoinflate their ears. These results show that air douches pass regularly through the Eustachian tube into the tympanic cavity even in atelectatic ears, which by definition suffer from aeration deficiency, which is often considered to be secondary to 'Eustachian tube obstruction', or alternatively 'Eustachian tube dysfunction'. Thus, the ability to force air through the Eustachian tube by politzerization is of no diagnostic value as an indicator of normal or abnormal tubal patency or functioning in atelectatic ears and most probably in allied conditions. PMID:2324620

  9. Relationship of Intraoperative Transit Time Flowmetry Findings to Angiographic Graft Patency at Follow-Up.

    PubMed

    Amin, Sanaz; Pinho-Gomes, Ana-Catarina; Taggart, David P

    2016-05-01

    Early and late graft occlusion remains a significant complication of coronary artery bypass grafting. Transit time flowmetry is the most commonly used imaging technique to assess graft patency intraoperatively. Although the value of transit time flowmetry for intraoperative quality control of coronary anastomosis is well established, its standard variables for predicting eventual graft failure remain controversial. This review readdresses the issue of intraoperative transit time flowmetry, with a particular emphasis on defining cutoff values for standard variables and correlating them with the ability to predict midterm and long-term graft patency for arterial and venous conduits. Further research is warranted to support clinically useful recommendations on the intraoperative application and interpretation of transit time flowmetry. PMID:26876343

  10. Patency of small laser iridotomy evaluated using anterior-segment optical coherence tomography.

    PubMed

    Nakabayashi, Seigo; Kawai, Motofumi; Yamaguchi, Toru; Yoshida, Akitoshi

    2014-01-01

    We report the case of a patient with recurrent acute angle-closure glaucoma who had undergone a previous laser iridotomy. Because the initial iridotomy was small, patency could not be determined by slit-lamp examination. Therefore, anterior-segment optical coherence tomography was used to evaluate the patency. Cross-sectional images showed the presence of a membrane with an anterior bowing configuration at the base of the iridotomy, suggesting that recurrent pupillary block was the causative mechanism. A repeat laser iridotomy was performed, with a resultant decrease in the intraocular pressure and widening of the anterior chamber angle. Anterior-segment optical coherence tomography may be helpful to confirm the status of a laser iridotomy, especially when the iridotomy is small. PMID:24711692

  11. Improving Access to Psychological Therapies and antidepressant prescribing rates in England: a longitudinal time-series analysis

    PubMed Central

    Sreeharan, Vaishnavee; Madden, Hugo; Lee, John Tayu; Millett, Christopher; Majeed, Azeem

    2013-01-01

    Background Antidepressant prescribing rates in England have been increasing since the 1970s. The impact of the Improving Access to Psychological Therapies (IAPT) initiative on antidepressant prescribing rates is unknown. Aim To investigate the impact of the establishment of IAPT services on antidepressant prescribing rates in primary care trusts (PCTs) in England. Design and setting A longitudinal time-series analysis, using PCT-level data from 2008 to 2011 set in England. Method A time-series analysis was conducted using PCT-level prescription data, dates of establishment of IAPT services, and covariate data for age, sex, and socioeconomic status. Statistical analysis was carried out using analysis of variance and a random-effect negative binomial model. Results Antidepressant prescribing rates in England increased by 10% per year during the study period (adjusted rate ratio = 1.10, 95% CI = 1.09 to 1.10). The implementation of IAPT services had no significant effect on antidepressant prescribing (adjusted rate ratio = 0.99, 95% CI = 0.99 to 1.00). Conclusion Introduction of a large-scale initiative to increase provision of psychological therapies has not curbed the long-term increased prescribing of antidepressants in England. PMID:23998846

  12. Mild anastomotic stenosis in patient-specific CABG model may enhance graft patency: a new hypothesis.

    PubMed

    Huo, Yunlong; Luo, Tong; Guccione, Julius M; Teague, Shawn D; Tan, Wenchang; Navia, José A; Kassab, Ghassan S

    2013-01-01

    It is well known that flow patterns at the anastomosis of coronary artery bypass graft (CABG) are complex and may affect the long-term patency. Various attempts at optimal designs of anastomosis have not improved long-term patency. Here, we hypothesize that mild anastomotic stenosis (area stenosis of about 40-60%) may be adaptive to enhance the hemodynamic conditions, which may contribute to slower progression of atherosclerosis. We further hypothesize that proximal/distal sites to the stenosis have converse changes that may be a risk factor for the diffuse expansion of atherosclerosis from the site of stenosis. Twelve (12) patient-specific models with various stenotic degrees were extracted from computed tomography images using a validated segmentation software package. A 3-D finite element model was used to compute flow patterns including wall shear stress (WSS) and its spatial and temporal gradients (WSS gradient, WSSG, and oscillatory shear index, OSI). The flow simulations showed that mild anastomotic stenosis significantly increased WSS (>15 dynes · cm(-2)) and decreased OSI (<0.02) to result in a more uniform distribution of hemodynamic parameters inside anastomosis albeit proximal/distal sites to the stenosis have a decrease of WSS (<4 dynes · cm(-2)). These findings have significant implications for graft adaptation and long-term patency. PMID:24058488

  13. Transposition of brachiobasilic arteriovenous fistulae: improving the cosmetic effect without compromising patency.

    PubMed

    van Dellen, David; Junejo, Muneer; Khambalia, Hussein; Campbell, Babatunde

    2016-01-01

    Introduction Subjects who undergo haemodialysis are living longer, which necessitates increasingly complex procedures for formation of arteriovenous fistulas. Basilic veins provide valuable additional venous 'real estate' but surgical transposition of vessels is required, which required a cosmetically disfiguring incision. A minimally invasive transposition method provides an excellent aesthetic alternative without compromised outcomes. Methods A retrospective review was made of minimally invasive brachiobasilic fistula transpositions (using two short incisions of <4 cm) between February 2005 and July 2011. Primary endpoints were one-year patency as well as the perioperative and late complications of the procedure. Results Thirty-one patients underwent 32 transposition procedures (eight pre-dialysis cases; 24 haemodialysis patients). All patients were treated with a minimally invasive method. Thirty-one procedures resulted in primary patency, with the single failure refashioned successfully. The only indication for a more invasive approach was intraoperative complications (two haematomas). All other complications presented late and were amenable to intervention (one aneurysm, one peri-anastomotic stricture). Conclusion Formation of arteriovenous fistulae using minimally invasive methods is a novel approach that ensures fistula patency with improved aesthetic outcomes and without significant morbidity. PMID:26688395

  14. [Alternative options for examination of the patency of peritoneo-venous shunts].

    PubMed

    Arató, Endre; Kollár, Lajos; Szilágyi, Károly; Litter, Ilona; Schmidt, Erzsébet

    2004-02-01

    For the treatment of refractory ascites we use the saphenoperitoneal shunt described by Pang in 1992 approximately 2 years. This procedure eliminates the most frequent complications of the former synthetic shunts: occlusion of the collector branches and infections as well. In addition, the use of autologous vein is cost-saving. The first Hungarian publications (K. Vincze and Z. Nagy et al.) reported good results, which are confirmed also by us, after we performed 21 operations. The publications until now usually describe the technique. This intervention is now a widely accepted one. On the other hand, just a small number of papers describe the options for the examination of patency and the follow-ups. We report about the algorithm used in our department after surgery to evaluate graft patency and surgical efficacy. A method to determine the volume of ascites developed by ourselves is described. We feel that the successful application of saphenoperitoneal shunts depends on very close follow-up. Considering that no objective method to check the patency does exist, we are sure that decisions about further operations can only be made if simultaneous diverse follow-up methods are available. PMID:15270521

  15. Sonothrombolysis with BR38 Microbubbles Improves Microvascular Patency in a Rat Model of Stroke

    PubMed Central

    Kampschulte, Marian; Hyvelin, Jean-Marc; Botteron, Catherine; Juenemann, Martin; Yeniguen, Mesut; Krombach, Gabriele A.; Kaps, Manfred; Spratt, Neil J.; Gerriets, Tibo; Nedelmann, Max

    2016-01-01

    Background Early recanalization of large cerebral vessels in ischemic stroke is associated with improved clinical outcome, however persisting hypoperfusion leads to poor clinical recovery despite large vessel recanalization. Limited experimental sonothrombolysis studies have shown that addition of microbubbles during treatment can improve microvascular patency. We aimed to determine the effect of two different microbubble formulations on microvascular patency in a rat stroke model. Methods We tested BR38 and SonoVue® microbubble-enhanced sonothrombolysis in Wistar rats submitted to 90-minute filament occlusion of the middle cerebral artery. Rats were randomized to treatment (n = 6/group): control, rt-PA, or rt-PA+3-MHz ultrasound insonation with BR38 or SonoVue® at full or 1/3 dose. Treatment duration was 60 minutes, beginning after withdrawal of the filament, and sacrifice was immediately after treatment. Vascular volumes were evaluated with microcomputed tomography. Results Total vascular volume of the ipsilateral hemisphere was reduced in control and rt-PA groups (p<0.05), but was not significantly different from the contralateral hemisphere in all microbubble-treated groups (p>0.1). Conclusions Microbubble-enhanced sonothrombolysis improves microvascular patency. This effect is not dose- or microbubble formulation-dependent suggesting a class effect of microbubbles promoting microvascular reopening. This study demonstrates that microbubble-enhanced sonothrombolysis may be a therapeutic strategy for patients with persistent hypoperfusion of the ischemic territory. PMID:27077372

  16. Effects of pentobarbital on upper airway patency during sleep.

    PubMed

    Eikermann, M; Eckert, D J; Chamberlin, N L; Jordan, A S; Zaremba, S; Smith, S; Rosow, C; Malhotra, A

    2010-09-01

    We hypothesised that pentobarbital would improve upper airway mechanics based on an increase in latency to arousal and amplitude of the phasic genioglossus electromyogram (EMG), and a decrease in the active upper airway critical closing pressure (P(crit)). 12 healthy subjects received pentobarbital (100 mg) or placebo in a double-blind, crossover protocol. During wakefulness, we measured the genioglossus reflex response to negative pressure pulses. During sleep, carbon dioxide was insufflated into the inspired air. Airway pressure was then decreased in a stepwise fashion until arousal from sleep. With basal breathing during sleep: flow rate was lower in volunteers given pentobarbital; end-tidal CO(2) concentration and upper airway resistance were greater; and P(crit) was unaffected (pentobarbital mean ± SD -11.7 ± 4.5 versus placebo -10.25 ± 3.6 cmH(2)O; p = 0.11). Pentobarbital increased the time to arousal (297 ± 63s versus 232 ± 67 s; p<0.05), at which time phasic genioglossus EMG was higher (6.2 ± 4.8% maximal versus 3.1 ± 3%; p<0.05) as were CO(2) levels. The increase in genioglossus EMG after CO(2) administration was greater after pentobarbital versus placebo. Pentobarbital did not affect the genioglossus negative-pressure reflex. Pentobarbital increases the time to arousal and stimulates genioglossus muscle activity, but it also increases upper airway resistance during sleep. PMID:20032012

  17. Effects of pentobarbital on upper airway patency during sleep

    PubMed Central

    Eikermann, M.; Eckert, D.J.; Chamberlin, N.L.; Jordan, A.S.; Zaremba, S.; Smith, S.; Rosow, C.; Malhotra, A.

    2012-01-01

    We hypothesised that pentobarbital would improve upper airway mechanics based on an increase in latency to arousal and amplitude of the phasic genioglossus electromyogram (EMG), and a decrease in the active upper airway critical closing pressure (Pcrit). 12 healthy subjects received pentobarbital (100 mg) or placebo in a double-blind, crossover protocol. During wakefulness, we measured the genioglossus reflex response to negative pressure pulses. During sleep, carbon dioxide was insufflated into the inspired air. Airway pressure was then decreased in a stepwise fashion until arousal from sleep. With basal breathing during sleep: flow rate was lower in volunteers given pentobarbital; end-tidal CO2 concentration and upper airway resistance were greater; and Pcrit was unaffected (pentobarbital mean±sd -11.7±4.5 versus placebo -10.25±3.6 cmH2O; p=0.11). Pentobarbital increased the time to arousal (297±63s versus 232±67 s; p<0.05), at which time phasic genioglossus EMG was higher (6.2±4.8% maximal versus 3.1±3%; p<0.05) as were CO2 levels. The increase in genioglossus EMG after CO2 administration was greater after pentobarbital versus placebo. Pentobarbital did not affect the genioglossus negative-pressure reflex. Pentobarbital increases the time to arousal and stimulates genioglossus muscle activity, but it also increases upper airway resistance during sleep. PMID:20032012

  18. Impact of top end anastomosis design on patency and flow stability in coronary artery bypass grafting.

    PubMed

    Koyama, Sachi; Kitamura, Tadashi; Itatani, Keiichi; Yamamoto, Tadashi; Miyazaki, Shohei; Oka, Norihiko; Nakashima, Kouki; Horai, Tetsuya; Ono, Minoru; Miyaji, Kagami

    2016-05-01

    For coronary artery bypass grafting (CABG), free grafts such as a saphenous vein or radial artery are often used for grafts to the lateral and posterior walls. However, the relationship between top-end anastomosis design and long-term patency remains unknown. Because coronary artery blood flow is dominant during diastole, top-end anastomosis may work better if the graft is directed towards the apex, whereas the shortest graft pathway appears to be most efficient. Using computational fluid dynamic models, we evaluated the hemodynamic variables that were affected by the angle of the top-end anastomosis. We created three-dimensional geometries of the aortic root with coronary arteries that involved 75 % stenosis in the obtuse marginal and postero-lateral branches. Two bypass models under vasodilator administration were created: in a"Model A", the top-end anastomosis is parallel to the long axis of the ascending aorta and the graft passed over the conus directed towards the apex; in a "Model B", the top-end anastomosis is directed toward the shortest pathway, and form near the right angles to the long axis of the ascending aorta. Wall shear stress (WSS) and its fluctuation, an oscillatory shear index (OSI) were evaluated to predict fibrosis progression at the anastomosis site and graft flow. Graft flow was 197.3 ml/min and 207.3 ml/min in the "Model A" and "Model B", respectively. The minimal WSS value inside the graft with the "Model A" and "Model B" was 0.53 Pa and 4.09 Pa, respectively, and the OSI value was 0.46 and 0.04, respectively. The top-end anastomosis of a free graft should be directed vertically towards the aorta to achieve the shortest graft pathway to maintain a high graft flow rate and to avoid the risks of endothelial fibrosis and plaque progression over the long-term after CABG. PMID:25910614

  19. Predictors of arteriovenous graft patency after radiologic intervention in hemodialysis patients.

    PubMed

    Lilly, R Z; Carlton, D; Barker, J; Saddekni, S; Hamrick, K; Oser, R; Westfall, A O; Allon, M

    2001-05-01

    Arteriovenous grafts in hemodialysis patients are prone to recurrent stenosis and thrombosis, requiring frequent radiologic and surgical interventions to optimize their long-term patency. Little is known about the factors that determine graft outcome after a radiologic intervention. The present study examined the clinical and radiologic predictors of intervention-free graft survival after elective angioplasty or thrombectomy. A prospective computerized database was used to determine the outcomes subsequent to all graft angioplasties (n = 330) and thrombectomies (n = 326) performed at the University of Alabama at Birmingham between April 1, 1996, and June 30, 1999. Primary graft survival rates after angioplasty and thrombectomy were 86% versus 43% at 1 month, 71% versus 30% at 3 months, 51% versus 19% at 6 months, and 28% versus 8% at 12 months, respectively. The median intervention-free graft survival time was substantially longer after angioplasty than thrombectomy (6.7 versus 0.6 months; P < 0.001). The superior outcome of angioplasty over thrombectomy was observed even for the subset of procedures with no residual stenosis (median survival, 6.9 versus 2.5 months; P < 0.001). The median graft survival was inversely related to the magnitude of residual stenosis for both elective angioplasty and thrombectomy. Median intervention-free graft survival after angioplasty was inversely related to the postangioplasty intragraft to systemic systolic pressure ratio (7.6, 6.9, and 5.6 months for ratios <0.4, 0.4 to 0.6, and >0.6, respectively; P < 0.001). Intervention-free graft survival after angioplasty or thrombectomy was not affected by graft location (forearm versus upper arm), number of stenotic sites, or presence of diabetes. In conclusion, graft survival is substantially longer after elective angioplasty than thrombectomy, even when the radiologic appearance after the procedure suggests complete resolution of the stenotic lesion. Moreover, the risk for requiring a

  20. Digital dual-rate burst-mode receiver for 10G and 1G coexistence in optical access networks.

    PubMed

    Mendinueta, José Manuel Delgado; Mitchell, John E; Bayvel, Polina; Thomsen, Benn C

    2011-07-18

    A digital dual-rate burst-mode receiver, intended to support 10 and 1 Gb/s coexistence in optical access networks, is proposed and experimentally characterized. The receiver employs a standard DC-coupled photoreceiver followed by a 20 GS/s digitizer and the detection of the packet presence and line-rate is implemented in the digital domain. A polyphase, 2 samples-per-bit digital signal processing algorithm is then used for efficient clock and data recovery of the 10/1.25 Gb/s packets. The receiver performance is characterized in terms of sensitivity and dynamic range under burst-mode operation for 10/1.25 Gb/s intensity modulated data in terms of both the packet error rate (PER) and the payload bit error rate (pBER). The impact of packet preamble lengths of 16, 32, 48, and 64 bits, at 10 Gb/s, on the receiver performance is investigated. We show that there is a trade-off between pBER and PER that is limited by electrical noise and digitizer clipping at low and high received powers, respectively, and that a 16/2-bit preamble at 10/1.25 Gb/s is sufficient to reliably detect packets at both line-rates over a burst-to-burst dynamic range of 14,5 dB with a sensitivity of -18.5 dBm at 10 Gb/s. PMID:21934767

  1. Influence of apical patency and filling material on healing process of dogs' teeth with vital pulp after root canal therapy.

    PubMed

    Holland, Roberto; Sant'Anna Júnior, Arnaldo; Souza, Valdir de; Dezan Junior, Eloi; Otoboni Filho, José Arlindo; Bernabé, Pedro Felício Estrada; Nery, Mauro Juvenal; Murata, Sueli Satomi

    2005-01-01

    The purpose of this study was to investigate the periapical healing process of dogs' teeth with or without apical patency and after root canal filling with two types of sealers. Forty roots of premolars and incisors were utilized. The root canals were over-instrumented and dressed with a corticosteroid-antibiotic solution for 7 days to obtain ingrowth of periapical connective tissue into the canals. After this period, the tissue was removed in half of the specimens (groups with patency) and preserved in the other half (groups without patency). Canals were filled by lateral condensation technique with gutta-percha points and either a calcium hydroxide-based sealer (Sealer Plus) or a Grossman's cement (Fill Canal). The animals were killed by anesthetic overdose 60 days after the endodontic treatment and anatomic pieces were obtained and prepared for histologic examination. Data were evaluated in a blind analysis on the basis of several histomorphologic parameters. The groups without patency had better results (p=0.01) than those in which the ingrown connective tissue was removed. Comparing the sealers, Sealer Plus had significantly better results (p=0.01) than Fill Canal. In conclusion, both the apical patency (presence or absence) and the type of root canal filling material influenced the periapical healing process in dogs' teeth with vital pulp after root canal treatment. The use of a calcium hydroxide-based sealer in teeth without apical patency yielded the best results among the experimental conditions proposed. PMID:16113927

  2. Kinetics of rubidium-82 after coronary occlusion and reperfusion. Assessment of patency and viability in open-chested dogs.

    PubMed Central

    Goldstein, R A

    1985-01-01

    Currently available noninvasive techniques are unable to rapidly assess artery patency and tissue viability during acute myocardial infarction. In prior studies, rubidium-82 (Rb-82), a short-lived positron emitter obtained from a generator, was validated as an indicator of flow with a model that included the rate constants for transfer into and out of the cell. Accordingly, in the current study, 20 open-chested dogs with experimental infarction were studied serially at base line, after coronary occlusion, and at reperfusion. Time-activity curves acquired with beta probes on the epicardial surface were used to measure flow and net transfer of rubidium. Flow decreased to 0.41 +/- 0.08 ml/min per gram during occlusion and increased to 2.73 +/- 0.56 ml/min per gram in potentially viable ischemic tissue, whereas flows were 0.32 +/- 0.08 during occlusion (P less than 0.05 vs. viable) and 1.58 ml/min per gram (P less than 0.002 vs. viable) in irreversibly injured tissue. The transfer rate constant for Rb-82, kT, at base line was +1.22 +/- 0.60 X 10(-3) s-1 and did not change significantly during occlusion in viable vs. nonviable samples (+1.41 +/- 1.27 vs. +0.93 +/- 1.51 X 10(-3) s-1, respectively), except that 4 out of 11 nonviable tissue samples had negative kTs. At reperfusion, viable myocardial samples were all positive (+1.26 +/- 1.58 X 10(-3) s-1), whereas all irreversibly injured tissues had a negative kT, indicating leakage of tracer (-1.50 +/- 1.10 X 10(-3) s-1, P less than 0.001). This study suggests that Rb-82 time-activity curves can be useful to determine patency of an infarct related artery and potential viability after reperfusion during myocardial infarction. Images PMID:3988934

  3. Vascular access and patient outcomes in hemodialysis: questions answered in recent literature.

    PubMed

    Añel, Ramon L; Yevzlin, Alexander S; Ivanovich, Peter

    2003-03-01

    Hemodialysis is not possible without access to the vascular system to provide an adequate and reliable source of blood flow through the hemodialyzer. Since maintenance hemodialysis therapy became a reality in the latter half of the twentieth century, no vascular access has exceeded the success and reliability of arteriovenous fistulae (AVF). They have the lowest infection and thrombosis rates, have the longest patency rates, and are associated with the best morbidity and mortality outcomes of any access modality. In the United States, the majority of patients starting hemodialysis do not have a primary AVF, which may explain why vascular access complications represent almost 20% of the total spending for hemodialysis. In addition, as much as 50% of hospitalization costs for end-stage renal disease are related to access issues. Every effort must be directed in the U.S. as well as elsewhere to promote the use of AVF whenever possible. In some European countries, more than 90% of patients have AVF as their hemodialysis access when nephrologists perform placement of vascular access. Already, some programs in the U.S. have recognized the need for trained nephrologists to provide these services. U.S. interventional nephrologists should be given the opportunity to learn AVF placement procedures to emulate their European counterparts, and thus improve U.S. dialysis outcomes. PMID:12662209

  4. Effect of Antithrombotic Agents on the Patency of PTFE-Covered Stents in the Inferior Vena Cava: An Experimental Study

    SciTech Connect

    Makutani, Shiro; Kichikawa, Kimihiko; Uchida, Hideo; Maeda, Munehiro; Konishi, Noboru; Hiasa, Yoshio; Yoshikawa, Tomohiro; Kimura, Yukio

    1999-05-15

    Purpose: To evaluate the efficacy of antithrombotic agents in the prevention of stenosis of polytetrafluoroethylene (PTFE)-covered stents in the venous system. Methods: Spiral Z stents covered with PTFE (PTFE-covered stents) were placed in the inferior vena cava (IVC) of 34 dogs. Nineteen dogs, used as a control group, were sacrificed at 2, 4, and 12 weeks. Fifteen dogs, previously given antithrombotic agents [cilostazol (n= 5), warfarin potassium (n= 5), cilostazol plus warfarin potassium (n= 5)] were sacrificed at 4 weeks, and then examined angiographically and histopathologically. The effect of the antithrombotic agents was compared between groups. Results: The patency rate of the antithrombotic agent group was 93% (14/15), which was higher than the control group rate of 63% (12/19). The mean stenosis rate of the patent stent at both ends and at the midportion was lower at 4 weeks in the antithrombotic agent group than in the control group. In particular, the mean stenosis rate in the cilostazol plus warfarin potassium group was significantly lower than the control group (Tukey's test, p < 0.05). The mean neointimal thickness of the patent stent at both ends and at the midportion was thinner at 4 weeks in the antithrombotic agent group than in the control group. In particular, the thickness of the neointima in the cilostazol plus warfarin potassium group was significantly decreased when compared with the control group (Tukey's test p < 0.05). At 4 weeks, endothelialization in the antithrombotic agent group tended to be almost identical to that in the control group. Conclusion: The present study suggests that administration of an antithrombotic agent is an effective way of preventing the stenosis induced by a neointimal thickening of PTFE-covered stents in the venous system.

  5. In vitro evaluation of stent patency and in-stent stenoses in 10 metallic stents using MR angiography.

    PubMed

    Hamer, O W; Borisch, I; Paetzel, C; Nitz, W R; Seitz, J; Feuerbach, S; Zorger, N

    2006-08-01

    In vitro study to investigate the suitability of contrast enhanced magnetic resonance angiography (CEMRA) for determination of stent patency and grading of in-stent stenoses in 10 metallic stents. The Acculink carotid, DynaLink, Easy Wallstent, JostentSelfX XF, Luminexx, Omnilink, sinus-SuperFlex, SMART, Symphony and ZA stent were separately placed in a vascular phantom. Dedicated stenoses inside the stents generated a concentric lumen narrowing of 50%. CEMRA was performed for each stent. Signal loss inside the stents and artificial lumen narrowing were assessed objectively using the evaluation software of the MR imager. Moreover, three blinded observers determined visibility of stent patency and in-stent stenoses subjectively on a 3-point scale and graded in-stent stenoses. Loss of signal intensity within the stent lumen ranged between 90% (Wallstent) and 5% (ZA), artificial lumen narrowing between 56% (Symphony) and 22% (ZA). For the Symphony and Wallstent, visibility of patency and in-stent stenoses was impaired and the observers' grading exaggerated the degree of stenoses (by 23% and 33%, respectively). For the remainder of stents, patency and stenoses were visible and stenoses were graded accurately (less than 10% discrepancy from reference standard). In this in vitro study, eight of 10 stents presented with MRI characteristics which enabled determination of stent patency and accurate grading of clinically relevant in-stent stenoses. PMID:16641417

  6. Effect of Patency File on Transportation and Curve Straightening in Canal Preparation with ProTaper System

    PubMed Central

    Hasheminia, Seyed Mohsen

    2013-01-01

    The aim of this ex vivo study was to evaluate the effect of using a patency file on apical transportation and curve straightening during canal instrumentation with the ProTaper rotary system. Seventy permanent mandibular first molars with mesiobuccal canals, measuring 18–23 mm in length and with a 25–40° curvature (according to the Schneider method), were selected. The working lengths were determined and the teeth were mounted and divided into two experimental groups: (A) prepared by the ProTaper system without using a patency file (n = 35) and (B) prepared by the ProTaper system using a patency file (n = 35). Radiographs taken before and after the preparation were imported into Photoshop software and the apical transportation, and curve straightening were measured. Data were analyzed using independent t-test. Partial correlation analysis was performed to evaluate the relationship between the initial curvature, transportation, and curve straightening (α = 0.05). Using a patency file during canal preparation significantly decreased both apical transportation and curve straightening (P < 0.001). There were significant relationships between the angle of curvature, transportation and curve straightening in pairs (P < 0.001). Apical patency is recommended during root canal preparation with the ProTaper rotary system. PMID:24159390

  7. Secondary arteriovenous fistulas: converting prosthetic AV grafts to autogenous dialysis access.

    PubMed

    Slayden, Geoffrey C; Spergel, Lawrence; Jennings, William C

    2008-01-01

    complications of AVGs may be resolved by conversion to a SAVF. Further, the limited lifespan of AVGs and the superiority of AVFs dictates that a plan be in place to transition the AVG patient to an AVF. Most, if not all, hemodialysis patients whose access is an AVG will have one or more anatomic sites and vessels suitable for an autogenous SAVF. Vessel mapping is critical in the evaluation of failing AVGs and in preparation for a SAVF. Cumulative patency rates exceeded 90% at 12 months for SAVFs in both patient groups in this report. The need for catheters was dramatically less in the patient group with an established SAVF conversion plan. PMID:18627564

  8. Vascular access in elderly patients with end-stage renal disease.

    PubMed

    Bessias, Nikolaos; Paraskevas, Kosmas I; Tziviskou, Effie; Andrikopoulos, Vassilios

    2008-01-01

    During the last few years, the number of elderly patients with end-stage renal disease (ESRD) has been increasing worldwide. Establishment of a viable vascular access is of primary importance in these patients. This review discusses the advantages and disadvantages of the available vascular access modalities [namely arteriovenous (AV) fistulae, AV grafts, and central venous catheters (CVCs)] in elderly ESRD patients. AV fistulae seem to be superior when compared with other vascular access alternatives with respect to patency, morbidity and mortality rates. On the other hand, due to the age-related advanced atherosclerosis in the elderly, higher failure rates for AV fistulae in this age group have been described. Two controversial issues, namely the higher infection and thrombosis rates in elderly ESRD patients, are also discussed. Current evidence suggests that old age should not comprise a drawback when selecting the appropriate vascular access modality (AV fistula, AV graft or CVC) for the performance of hemodialysis. The possible vascular access options in elderly ESRD patients should not be different from younger individuals. PMID:18792799

  9. The validity of canine platelet aggregometry in predicting vascular graft patency.

    PubMed

    Greisler, H P; McGurrin, J F; Klosak, J J; Tattersall, C W; Ellinger, J; Henderson, S C; Cabusao, E A

    1990-01-01

    Several laboratories have found canine platelet aggregometry predictive of thrombotic potential in vascular grafts. Adenosine diphosphate (ADP) is a frequently used agonist, often at unspecified or differing concentrations. This study was designed to evaluate the predictive value of ADP-induced platelet aggregometry and the validity of the methodology. Platelet aggregometry in response to 2 x 10(-5) M ADP was assayed in 70 dogs. Twenty-six percent were aggregators, 51% were non-aggregators, and 20% were indeterminant. All dogs were then treated with aspirin and dipyridamole. Vascular prostheses were implanted bilaterally (aorto-iliac) and anti-platelet therapy continued for two weeks. Dose-response to ADP was studied at three concentrations in 20 dogs. At 2 x 10(-5) 1/20 aggregated, at 4 x 10(-5) 3/19 aggregated and at 2 x 10(-4) 15/20 aggregated. Time between samples and study was evaluated in 11 dogs, with 2/11 changing from non-aggregator to aggregator at two or three hours. Daily reproducibility was studied in 70 dogs, 14 of which changed aggregation status between days. Patency was 58/68 (85%) for non-aggregators, 23/34 (68%) for aggregators (p = 0.038). Platelet aggregometry has significant predictive value for graft patency but methodology must be specified and standardized. PMID:2262494

  10. Single and Tandem Stents in Sheep Iliac Arteries: Is There a Difference in Patency?

    SciTech Connect

    Schuermann, Karl; Vorwerk, Dierk; Buecker, Arno; Grosskortenhaus, Stefanie; Guenther, Rolf W.

    1998-09-15

    Purpose: To compare patency and neointima formation of single and tandem arterial stents. Methods: In each of six sheep, two Memotherm nitinol stents (tandem stents) were inserted into the external iliac artery on one side and a single stent into the artery on the opposite side. The size of the iliac lumen was assessed in the proximal, middle, and distal segments of the stents by intravascular ultrasound (IVUS) before, immediately after, and 1 month after implantation when the sheep were killed. Neointimal thickness was determined in the proximal, middle, and distal segments of each stent by light microscopy. Results: All stents remained patent. There was no significant difference in lumen and neointimal thickness between single and tandem stents. Cranial tandem stents showed a significantly wider lumen and smaller neointimal thickness than caudal tandem stents. In the proximal and distal segments, the lumen of the stents was significantly smaller and the neointimal thickness greater than in the middle segment; differences in neointimal thickness were significant only between the proximal and the middle segment. Conclusion: In an experimental setting, tandem stents did not interfere with one another with regard to patency and neointima formation when compared with a single contralateral stent. Neointimal thickening after stent insertion seems to be inversely related to the original arterial diameter.

  11. Long-term Patency of Primary Arterial Repair and the Modified Cold Intolerance Symptom Severity Questionnaire

    PubMed Central

    Lannau, Bernd; Bliley, Jacqueline; James, Isaac B.; Wang, Sheri; Sivak, Wesley; Kim, Kang; Fowler, John

    2015-01-01

    Background: The goal of this study was to assess the long-term arterial patency of repaired arteries in the upper extremity and any morbidity resulting from the subsequent occlusion of these vessels. Concurrently, a new questionnaire, the modified Cold Intolerance Symptom Severity (mod CISS) questionnaire, was developed to allow for better assessment of cold intolerance. Methods: Thirteen patients who had undergone repair of the radial (4 patients), ulnar (6 patients), brachial (1 patient), digital (1), and an undefined lower arm artery (1) were examined using questionnaires, physical examination, and high-resolution ultrasound. Results: Outcome measures that were statistically significantly worse in the group of patients who presented with nerve injuries included cold intolerance symptoms, Disabilities of the Arm, Shoulder, and Hand score, Michigan Hand Questionnaire, and grip strength (middle setting on dynamometer). The results from the mod CISS correlated with high statistical significance with the results of the CISS score for the injured hand. Of note, wrist extension was significantly better with patent arteries. Conclusions: Sixty-seven percent of arterial repairs remained patent at 6 years (mean) follow-up. The presence of nerve injury has a higher impact on the outcome metrics assessed in this study than arterial patency. Our modification of the CISS score enhances its utility as a survey of cold intolerance. PMID:26893976

  12. Perception of Better Nasal Patency Correlates with Increased Mucosal Cooling after Surgery for Nasal Obstruction

    NASA Astrophysics Data System (ADS)

    Garcia, Guilherme; Sullivan, Corbin; Frank-Ito, Dennis; Kimbell, Julia; Rhee, John

    2014-11-01

    Nasal airway obstruction (NAO) is a common health problem with 340,000 patients undergoing surgery annually in the United States. Traditionally, otolaryngologists have focused on airspace cross-sectional areas and nasal resistance to airflow as objective measures of nasal patency, but neither of these variables correlated consistently with patients' symptoms. Given that the sensation of nasal airflow is also associated with mucosal cooling (i.e., heat loss) during inspiration, we investigated the correlation between the sensation of nasal obstruction and mucosal cooling in 10 patients before and after NAO surgery. Three-dimensional models of the nasal anatomy were created based on pre- and post-surgery computed tomography scans. Computational fluid dynamics (CFD) simulations were conducted to quantify nasal resistance and mucosal cooling. Patient-reported symptoms were measured by a visual analog scale and the Nasal Obstruction Symptom Evaluation (NOSE), a disease-specific quality of life questionnaire. Our results revealed that the subjective sensation of nasal obstruction correlated with both nasal resistance and heat loss, but the strongest correlation was between the NOSE score and the nasal surface area where heat flux exceeds 50 W /m2 . In conclusion, a significant post-operative increase in mucosal cooling correlates well with patients' perception of better nasal patency after NAO surgery.

  13. Long-term patency (9 1/2 years) and atherosclerosis of a polytetrafluoroethylene (Gortex) coronary artery bypass graft.

    PubMed

    Vlay, S C; Malik, A Z

    1998-01-01

    The patency of a polytetrafluoroethylene (Gortex) graft 9 1/2 years after coronary artery bypass graft surgery (CABG) is demonstrated. While this material is not commonly used as a conduit because of limited success in the past, this case demonstrates that, given the right circumstances, long-term patency is possible. Since available conduits for CABG are quite often limited, viable alternatives may be lifesaving and require further evaluation. In addition to mechanical considerations such as size, length, and material, anticoagulation and strict management of hyperlipidemia may be critical. PMID:9474468

  14. Results of a Peripheral Cutting Balloon Prospective Multicenter European Registry in Hemodialysis Vascular Access

    SciTech Connect

    Peregrin, Jan H. Rocek, Miloslav

    2007-04-15

    Purpose. To report initial experience with the Peripheral Cutting Balloon (PCB) in treatment of failing hemodialysis shunts. Methods. A total of 190 patients (95 men, 95 women; average age 64.4 {+-} 11.9 years, range 32-87 years) who were treated with the PCB for pressure-resistant stenosis, restenosis or failed percutaneous transluminal angioplasty (PTA) in the venous limb of an arteriovenous shunt were followed in seven European centers using a simple registry. The group consisted of 109 de novo lesions (57%) and 79 restenotic lesions (43%). Results. Technical success was achieved in 88.9% of cases. Primary patency was as follows (the results for whole group and simultaneous results for de novo lesions and restenoses are presented): 1 month (140 patients followed): 94%, 98%, and 93%; 3 months (116 patients followed): 93%, 98%, and 92%; 6 months (40 patients followed): 85%, 92%, and 79%; 12 months (27 patients followed): 74%, 87%, and 48%. No complication occurred. Patients experienced an equal or lower level of pain during the procedure compared with conventional PTA. Conclusion. The PCB proved to be successful in dilating pressure-resistant stenoses. We cannot conclude whether PCB angioplasty can lower the restenosis rate in hemodialysis access lesions, but the long-term patency for de novo lesions is high. A further randomized study is advisable.

  15. Perception of better nasal patency correlates with increases in mucosal cooling after surgery for nasal obstruction

    PubMed Central

    Sullivan, Corbin D.; Garcia, Guilherme J. M.; Frank, Dennis O.; Kimbell, Julia S.; Rhee, John S.

    2014-01-01

    Objectives 1. Quantify mucosal cooling (i.e., heat loss) spatially in the nasal passages of nasal airway obstruction (NAO) patients before and after surgery using computational fluid dynamics (CFD). 2. Correlate mucosal cooling with patient-reported symptoms, as measured by the Nasal Obstruction Symptom Evaluation (NOSE) and a visual analog scale (VAS) for sensation of nasal airflow. Study Design Prospective Setting Academic tertiary medical center. Subjects and Methods Computed tomography (CT) scans and NOSE and VAS surveys were obtained from 10 patients before and after surgery to relieve NAO. Three-dimensional models of each patient’s nasal anatomy were used to run steady-state CFD simulations of airflow and heat transfer during inspiration. Heat loss across the nasal vestibule and the entire nasal cavity, and the surface area of mucosa exposed to heat fluxes > 50 W/m2 were compared pre- and post-operatively. Results After surgery, heat loss increased significantly on the pre-operative most obstructed side (p values < 0.0002). A larger surface area of nasal mucosa was exposed to heat fluxes > 50 W/m2 after surgery. The best correlation between patient-reported and CFD measures of nasal patency was obtained for NOSE against surface area in which heat fluxes > 50 W/m2 (Pearson r = −0.76). Conclusion A significant post-operative increase in mucosal cooling correlates well with patients’ perception of better nasal patency after NAO surgery. CFD-derived heat fluxes may prove to be a valuable predictor of success in NAO surgery. PMID:24154749

  16. Positive correlation between patency and mRNA levels for cyclooxygenase-2 and prostaglandin E synthase in the uterine cervix of bitches with pyometra.

    PubMed

    Tamada, Hiromichi; Adachi, Nahoko; Kawate, Noritoshi; Inaba, Toshio; Hatoya, Shingo; Sawada, Tsutomu

    2016-03-01

    Factors involved in patency of uterine cervices in the bitch with pyometra remain to be clarified. This study examined relationship between patency and mRNA levels for inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-1, COX-2 and prostaglandin E synthase (PGES) in the uterine cervix of bitches with pyometra. Cervical patency was measured by inserting the stainless steel rods with different diameter into cervical canals. Levels of mRNA expression were determined by semi-quantitative reverse transcription-polymerase chain reaction. The cervical patency was positively correlated with mRNA levels for COX-2 and PGES, but not those for iNOS and COX-1. The results suggest that gene expression of COX-2 and PGES may be involved in the regulation of patency in the uterine cervix of bitches with pyometra. PMID:26596635

  17. Positive correlation between patency and mRNA levels for cyclooxygenase-2 and prostaglandin E synthase in the uterine cervix of bitches with pyometra

    PubMed Central

    TAMADA, Hiromichi; ADACHI, Nahoko; KAWATE, Noritoshi; INABA, Toshio; HATOYA, Shingo; SAWADA, Tsutomu

    2015-01-01

    Factors involved in patency of uterine cervices in the bitch with pyometra remain to be clarified. This study examined relationship between patency and mRNA levels for inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-1, COX-2 and prostaglandin E synthase (PGES) in the uterine cervix of bitches with pyometra. Cervical patency was measured by inserting the stainless steel rods with different diameter into cervical canals. Levels of mRNA expression were determined by semi-quantitative reverse transcription-polymerase chain reaction. The cervical patency was positively correlated with mRNA levels for COX-2 and PGES, but not those for iNOS and COX-1. The results suggest that gene expression of COX-2 and PGES may be involved in the regulation of patency in the uterine cervix of bitches with pyometra. PMID:26596635

  18. Transcatheter Arterial Chemoembolization of Liver Tumors: Effects of Embolization Protocol on Injectable Volume of Chemotherapy and Subsequent Arterial Patency

    SciTech Connect

    Geschwind, Jean-Francois H.; Ramsey, Douglas E.; Wal, B.C.H. van der; Kobeiter, Hicham; Juluru, Krishna; Hartnell, George G.; Choti, Michael A.

    2003-04-15

    The purpose of this study was to determine whether transcatheter arterial chemoembolization (TACE) protocol affects the total volume of chemotherapy injected into the liver as well as subsequent arterial patency. A total of 160 patients with primary or secondary liver cancer were treated with 3 different chemoembolization protocols at a single institution. Data were analyzed retrospectively.Group 1 (n = 36) consisted of slurry of chemotherapy,oil and polyvinyl alcohol particles (PVA), group 2 (n =91), chemotherapy and oil followed by PVA, and group 3(n = 33), chemotherapy and oil followed by Gelfoampledgets. The total volume of chemotherapy injected into the liver was recorded. Arterial patency was determined during subsequent chemoembolizations. The mean percentage of total intended chemotherapydose administered was 54.6% for group 1, 75.3% for group 2, and 80.6% for group 3. Arterial patency at follow-up angiography was 56% for group 1, 74% for group 2, and 81% for group 3. The slurry protocol (group 1) significantly reduced arterial patency and injectable volume of chemotherapy during TACE.

  19. Who Has Access to Dual Credit in Illinois? Examining High School Characteristics and Dual Credit Participation Rates. Policy Research: IERC 2013-4

    ERIC Educational Resources Information Center

    Taylor, Jason L.; Lichtenberger, Eric J.

    2013-01-01

    This research brief examines the relationship between high schools' dual credit participation rate and key characteristics of high schools. The brief establishes that there are differences in students' access to dual credit based on the observed characteristics of the high schools in which they enroll. For example, it was found that relative to…

  20. Differences in Hispanic Access and Success Rates for Health-Related Studies in Texas Health-Related Institutions: A Multiyear, Statewide Investigation

    ERIC Educational Resources Information Center

    Cox, Shelley M.

    2013-01-01

    Purpose: The purpose of this study was to examine Hispanic student access and success in health-related degrees by examining enrollment and graduation rates over a period of 13 years. Archival data were obtained from the THECB consisting of the number of Hispanic students enrolled and number of degrees awarded in the health-related degrees at…

  1. Real-Time Evaluation of Anterior Choroidal Artery Patency During Aneurysm Clipping

    PubMed Central

    Zhao, David Y; Nayar, Vikram V; Kalhorn, Christopher G; McGrail, Kevin M; Mandir, Allen S; Minahan, Robert E

    2016-01-01

    Inadvertent occlusion of the anterior choroidal artery during aneurysm clipping can cause a disabling stroke in minutes. We evaluate the clinical utility of direct cortical motor evoked potential (MEP) monitoring during aneurysm clipping, as a real-time assessment of arterial patency, prior to performing indocyanine green videoangiography.   Direct cortical MEPs were recorded in seven patients undergoing surgery for aneurysms that involved or abutted the anterior choroidal artery. The aneurysms clipped in those seven patients included four anterior choroidal artery aneurysms and six posterior communicating artery aneurysms. Serial MEP recordings were performed during the intradural dissection, aneurysm exposure, and clip placement. A significant change in MEPs after clip placement would prompt immediate inspection and removal or repositioning of the clip. If the clip placement appeared satisfactory and MEP recordings were stable, then an intraoperative indocyanine green videoangiogram was performed to confirm obliteration of the aneurysm and patency of the arteries.  Seven patients underwent successful clipping of anterior choroidal artery aneurysms and posterior communicating artery aneurysms using direct cortical MEP monitoring, with good clinical and radiographic outcomes. In six patients, no changes in MEP amplitudes were observed following permanent clip placement. In one patient, a profound decrease in MEP amplitude occurred 220 seconds after placement of a permanent clip on a large posterior communicating aneurysm. An inspection revealed that the anterior choroidal artery was kinked. The clip was immediately removed, and the MEP signals returned to baseline shortly thereafter. A clip was then optimally placed, and the patient awoke without neurologic deficit.  Direct cortical MEPs are a useful adjunct to standard electrophysiologic monitoring in aneurysm surgery, particularly when the anterior choroidal artery or lenticulostriate arteries are at

  2. Children's Health in Washington, D.C.: Access and Health Challenges despite High Insurance Coverage Rates. Research Highlights

    ERIC Educational Resources Information Center

    Adamson, David M.

    2009-01-01

    In Washington, D.C., the vast majority of children have health insurance. Yet District children often lack sufficient access to medical care and face significant health threats from chronic conditions and risk factors such as exposure to violence in schools and neighborhoods. These findings emerged from an assessment of children's health in…

  3. Elastic Recoil after Balloon Angioplasty in Hemodialysis Accesses: Does It Actually Occur and Is It Clinically Relevant?

    PubMed

    Rajan, Dheeraj K; Sidhu, Arshdeep; Noel-Lamy, Maxime; Mahajan, Ashish; Simons, Martin E; Sniderman, Kenneth W; Jaskolka, Jeffrey; Tan, Kong Teng

    2016-06-01

    Purpose To qualify and quantify elastic recoil and determine its effect on access patency. Materials and Methods Research ethics board approval was obtained and all patients signed an informed consent form. This was a prospective, nonrandomized study of mature accesses that underwent balloon percutaneous transluminal angioplasty (PTA) between January 2009 and December 2012. After PTA, completion fistulography was performed at 0-, 5-, 10-, and 15-minute intervals. From Digital Imaging and Communications in Medicine images, percentage of lesion stenosis before and after PTA was measured at each time point. A total of 76 patients (44 men, 32 women; mean age, 59.6 years) were enrolled and underwent 154 PTAs in 56 grafts and 98 fistulas. Venous elastic recoil was defined as recurrent luminal narrowing greater than 50% within 15 minutes after full effacement of the stenosis by the angioplasty balloon. Data collected included sex, age, access type and location, lesion location, length, and time to next intervention. Access patency was estimated by using Kaplan-Meier survival method, association of variables with the risk of loss of patency was assessed by using a Cox proportional hazards model, and a multiple variable model was examined by considering all variables. Results Technical success of PTA with less than 30% residual stenosis was 78%. By 15 minutes, 15.6% (24 of 154) of treated lesions recurrently narrowed by more than 50%, with a majority observed at 5 minutes (15 of 24). Technical failure of PTA was predictive of elastic recoil (P < .001), as was cephalic arch stenosis in fistulas (P = .047) and autogenous fistulas (P = .04). Elastic recoil, when it did occur, did not influence patency. Six-month primary patency was 34.8% in grafts and 47.1% in fistulas. Conclusion Venous elastic recoil after PTA of stenoses in hemodialysis access circuits is common, but its occurrence does not influence access primary patency after PTA. (©) RSNA, 2015. PMID:26694051

  4. Assessing the patency of mediastinal and thoracic inlet veins: value of MR imaging.

    PubMed

    Hansen, M E; Spritzer, C E; Sostman, H D

    1990-12-01

    To assess the accuracy of MR imaging in the evaluation of patients with suspected thoracic venous obstruction, hospital records and MR studies of 31 such patients were reviewed. Gradient-recalled echo, spin-echo, or cine MR techniques were used. In 26 of the 31 patients, venous obstruction was confirmed by CT, venography, sonography, surgery, or autopsy. Causes included tumor invasion, compression of veins, coagulopathy, or indwelling catheters. MR detected an abnormality of the superior vena cava in all 16 cases in which it was seen on other tests. Abnormality of the internal or external jugular veins was detected in all six cases in which other studies were abnormal. Abnormality of veins in the shoulder region was detected by MR in 10 of 12 patients in whom such disease was seen on other tests. The two interpretive errors were caused by nonocclusive clot, short (less than 2-cm) occlusions, and metallic artifact. Overall, MR correctly identified abnormality in 32 of 34 vessels (sensitivity, 94%). In all cases, a negative MR study was found to be a true negative (no false positives in 42 normal vessels; specificity, 100%). We conclude that MR is an accurate means of assessing patency of the thoracic inlet and mediastinal veins. Its noninvasive nature and multiplanar capability contribute to its usefulness in this clinical setting. PMID:2122662

  5. Influence of nasotrigeminal afferents on medullary respiratory neurones and upper airway patency in the rat.

    PubMed

    Dutschmann, M; Paton, J F R

    2002-05-01

    Noxious stimulation of the nasal mucosa evokes a nasotrigeminal reflex (diving response), consisting of apnoea, bradycardia and vasoconstriction. However, the central mechanisms underlying the respiratory component remain unclear. Here, we describe the influence of nasotrigeminal stimulation (NS) on different types of ventral medullary respiratory neurones and upper airway patency in the rat. In an arterially perfused working heart-brainstem preparation (WHBP), NS was induced by either irrigation of the nasal passage with cold saline (100-200 microl) or electrical stimulation of the trigeminal ethmoidal nerve (EN5, 20 Hz, 10 s, 100 micros, 0.5-2 V). Both stimuli evoked apnoea, bradycardia, a pressor response, persistent discharge in the recurrent laryngeal nerve and marked glottal adduction (P<0.001). NS evoked a distinct pattern of response in respiratory neurones: inspiratory (I) neurones ceased firing and hyperpolarized (n=19), while postinspiratory neurones depolarized (n=10) and discharged persistently. The latency of EN5-evoked synaptic responses (excitatory to postinspiratory neurones 12.3+/-2.8 ms, n=10; inhibitory to inspiratory neurones 11.8+/-1.9 ms; n=19) was comparable. During the NS-evoked apnoea burst discharges were superimposed on a maintained level of tonic activity recorded from both the recurrent laryngeal nerve (n=4) and some postinspiratory neurones (n=7). The physiological significance of these "apnoeic rhythms" is discussed. We conclude that the cardiorespiratory components of the diving response are mediated by activation of distinct sets of postinspiratory respiratory neurones. PMID:11976936

  6. Re-establishing apical patency after obturation with Gutta-percha and two novel calcium silicate-based sealers

    PubMed Central

    Agrafioti, Anastasia; Koursoumis, Anastasios D.; Kontakiotis, Evangelos G.

    2015-01-01

    Objective: Aim of the present study was to evaluate the retreatability and reestablishment of apical patency of two calcium silicate-based sealers, TotalFill BC Sealer (BCS) and mineral trioxide aggregate Fillapex (MTA F), versus AH Plus, when used in combination with Gutta-percha (GP). Materials and Methods: The canals of 54 single-rooted anterior teeth were instrumented and filled with GP/AH Plus (Group A), GP/MTA F (Group B), or GP/BCS (Group C) using continuous wave obturation technique. The groups were subdivided into subgroups with the master-GP cone placed to the working length (WL) or intentionally 2 mm short. The retreatment procedures were performed using ultrasonics, chloroform, rotary, and hand files. The ability to establish the patency and reach WL was determined as well as the time taken to reach WL was calculated in minutes. Furthermore, the samples were observed under a dental, optical microscope, after vertically splitting them. Results: The WL and patency were reestablished in 100% of specimens in all groups. The Mann–Whitney U-test indicated that there was a significant difference in the amount of time required to reach WL between the groups (P < 0.05) with group GP/BCS short of the WL showing the most amount of time to be retreated. Conclusion: The novel calcium silicate-based sealers are negotiable under simple root canal anatomy. However, the conventional retreatment techniques are not able to fully remove them. PMID:26929681

  7. Platelet to Lymphocyte Ratio Can be a Predictor of Infarct-Related Artery Patency in Patients With ST-Segment Elevation Myocardial Infarction.

    PubMed

    Yayla, Çağrı; Akboğa, Mehmet Kadri; Canpolat, Uğur; Akyel, Ahmet; Yayla, Kadriye Gayretli; Doğan, Mehmet; Yeter, Ekrem; Aydoğdu, Sinan

    2015-10-01

    Patency of infarct-related artery (IRA) in patients with ST-segment elevation myocardial infarction (STEMI) before primary percutaneous coronary intervention (pPCI) is associated with lower mortality and better clinical outcome. However, there were little data regarding the predictors of IRA patency before pPCI in the setting of STEMI. We aimed to assess the association of platelet to lymphocyte ratio (PLR) with IRA patency in STEMI. A total of 452 patients were enrolled and categorized as occluded or patent IRA. Patency IRA was assessed by the thrombolysis in myocardial infarction (TIMI) flow grade. Blood samples were obtained on admission to calculate PLR. Of all patients, 92 (20.4%) patients revealed pre-pPCI TIMI 3 flow in IRA. The PLR was significantly higher in occluded IRA group (138.4 ± 51.4 vs 95.4 ± 43.5, P < .001). Glucose, troponin I, and neutrophil to lymphocyte ratio (NLR) levels were also higher in occluded IRA group (P < .05). Multivariate regression analysis demonstrated the PLR (odds ratio [OR]: 0.987; 95% confidence interval [CI]: 0.978-0.995, P = .002) and NLR (OR: 0.758; 95% CI: 0.584-0.985, P = .038) on admission as independent predictors of IRA patency. In conclusion, a higher PLR is a powerful and independent predictor of IRA patency in patients with STEMI before pPCI. PMID:25712290

  8. Young Australian adults with NF1 have poor access to health care, high complication rates, and limited disease knowledge.

    PubMed

    Oates, Emily C; Payne, Jonathan M; Foster, Sheryl L; Clarke, Nigel F; North, Kathryn N

    2013-04-01

    Neurofibromatosis type 1 (NF1) is a multisystem disease associated with a lifelong risk of debilitating and potentially life-limiting complications, however many adults with NF1 have no regular health surveillance. We interviewed and examined 17 young adults with NF1 between the ages of 25 and 33. Most had not been assessed for NF1-related complications within the previous 8 years, including patients with known serious vascular complications, for example, renal artery stenosis. Acute and/or chronic pain, particularly back and plexiform-related pain were common symptoms, and despite a significant impact on quality of life, was untreated in most instances. Symptom and examination-directed imaging revealed serious complications in 41% of the cohort. These included severe spinal cord compression (two cases), a highly SUV avid lesion suggestive of malignancy (one case), and a Juvenile Pilocytic Astrocytoma in a patient without any previous NF1-related complications. Few study participants had a good understanding of NF1, its associated risks and complications, and many had not sought appropriate medical advice as questions or problems arose. NF1-related cognitive deficits in some participants, and the lack of a clear source of expert medical advice for adults with NF1 likely contributed to poor health surveillance and management in this population. Overall, these findings suggest that many Australian adults with NF1 are at risk of serious and life-threatening medical complications, but are not accessing and receiving adequate health care. Access to multidisciplinary adult clinics that specialize in NF1 may address many of the unmet health needs of young adults with NF1. PMID:23427176

  9. Examining the Impact of the National Institutes of Health Public Access Policy on the Citation Rates of Journal Articles

    PubMed Central

    De Groote, Sandra L.; Shultz, Mary; Smalheiser, Neil R.

    2015-01-01

    Purpose To examine whether National Institutes of Health (NIH) funded articles that were archived in PubMed Central (PMC) after the release of the 2008 NIH Public Access Policy show greater scholarly impact than comparable articles not archived in PMC. Methods A list of journals across several subject areas was developed from which to collect article citation data. Citation information and cited reference counts of the articles published in 2006 and 2009 from 122 journals were obtained from the Scopus database. The articles were separated into categories of NIH funded, non-NIH funded and whether they were deposited in PubMed Central. An analysis of citation data across a five-year timespan was performed on this set of articles. Results A total of 45,716 articles were examined, including 7,960 with NIH-funding. An analysis of the number of times these articles were cited found that NIH-funded 2006 articles in PMC were not cited significantly more than NIH-funded non-PMC articles. However, 2009 NIH funded articles in PMC were cited 26% more than 2009 NIH funded articles not in PMC, 5 years after publication. This result is highly significant even after controlling for journal (as a proxy of article quality and topic). Conclusion Our analysis suggests that factors occurring between 2006 and 2009 produced a subsequent boost in scholarly impact of PubMed Central. The 2008 Public Access Policy is likely to be one such factor, but others may have contributed as well (e.g., growing size and visibility of PMC, increasing availability of full-text linkouts from PubMed, and indexing of PMC articles by Google Scholar). PMID:26448551

  10. Construction of Transjugular Intrahepatic Portosystemic Shunt: Bare Metal Stent/Stent-graft Combination versus Single Stent-graft, a Prospective Randomized Controlled Study with Long-term Patency and Clinical Analysis

    PubMed Central

    Wang, Chang-Ming; Li, Xuan; Fu, Jun; Luan, Jing-Yuan; Li, Tian-Run; Zhao, Jun; Dong, Guo-Xiang

    2016-01-01

    Background: Balanced adjustment of the portal vein shunt volume during a transjugular intrahepatic portosystemic shunt (TIPS) is critical for maintaining liver perfusion and decreasing the incidence of liver insufficiency. A stent-graft is proved to be superior to a bare metal stent (BMS) for the construction of a TIPS. However, the clinical results of the combination application of stents and stent-grafts have not been determined. This study aimed to compare the technique of using a combination of stents and stent-grafts with using a single stent-graft to construct a TIPS. Methods: From April 2011 to November 2014, a total of fifty patients were randomly assigned to a stents-combination group (Group I, n = 28) or a stent-graft group (Group II, n = 22). Primary patency rates were calculated. Clinical data, including the technical success rate, bleeding control results, incidence of encephalopathy, liver function preservation, and survival rate, were assessed. Results: Technically, the success rate was 100% for both groups. The primary patency rates at 1, 2, and 3 years for Group I were 96%, 84%, and 77%, respectively; for Group II, they were 90%, 90%, and 78%, respectively. The survival rates at 1, 2, and 3 years for Group I were 79%, 74%, and 68%, respectively; for Group II, they were 82%, 82%, and 74%, respectively. The incidence of hepatic encephalopathy was 14.3% for Group I and 13.6% for Group II. The Child-Pugh score in Group I was stable at the end of the follow-up but had significantly increased in Group II (t = −2.474, P = 0.022). Conclusions: The construction of a TIPS with either the single stent-graft or BMS/stent-graft combination is effective for controlling variceal bleeding. The BMS/stent-graft combination technique is superior to the stent-graft technique in terms of hepatic function preservation indicated by the Child-Pugh score. However, considering the clinical results of the TIPS, the two techniques are comparable in their primary shunt

  11. Cephalometric Pattern and Nasal Patency in Children with Primary Snoring: The Evidence of a Direct Correlation

    PubMed Central

    Zicari, Anna Maria; Duse, Marzia; Occasi, Francesca; Luzzi, Valeria; Ortolani, Emanuela; Bardanzellu, Flaminia; Bertin, Serena; Polimeni, Antonella

    2014-01-01

    Introduction Sleep disordered breathing (SDB) might affect craniofacial growth and children with obstructive sleep apnea syndrome present an increase in total and lower anterior heights of the face and a more anterior and inferior position of the hyoid bone when compared to nasal breathers. Objective To investigate the correlation between rhinomanometric and cephalometric parameters in children with primary snoring (PS), without apnea or gas exchange abnormalities. Materials and Methods Thirty children with habitual snoring (16 females and 14 males) aged 4–8 years (mean age 6.85±1.51 years) were selected by a SDB validate questionnaire. All subjects underwent lateral cephalometric, panoramic radiographies. Results In our sample 10 children (33%) had snoring 3 nights/week, 11 (37%) 4–6 nights/week and 9 (30%) every night/week. Overall 7 patients (23.3%) were affected by adenoid hypertrophy (AH), 4 (13.3%) by tonsillar hypertrophy (TH) and 13 (43.3%) by AH and TH. We found a more vertical position of the hyoid bone to the mandibular plane (H⊥VT) in patients with a higher frequency (7.3±2.7 vs 7.6±3.7 vs 10.9±2.5 in children snoring 3 nights/week, 4–6 nights/week and every night/week respectively; p = 0.032). Concerning nasal patency significant correlations were found with ANB (maxillary and jaw position with respect to the cranial base), NS∧Ar (growth predictor), sumangle, FMA (total divergence), SnaSnp∧GoMe (inferior divergence), BaN∧PtGn (facial growth pattern), Phw1_PsP (posterosuperior airway space), AHC3H (the horizontal distance between the most anterosuperior point of the hyoid bone and the third cervical vertebra). Conclusion The present study supports the relationship between nasal obstruction and specific craniofacial characteristics in children with primary snoring and lead us to hypothesize that nasal obstruction might explain the indirect link between snoring and cephalometric alterations. PMID:25360610

  12. Silencing the hydroxyproline-rich glycopeptide systemin precursor in two accessions of Nicotiana attenuata alters flower morphology and rates of self-pollination.

    PubMed

    Berger, Beatrice; Baldwin, Ian T

    2009-04-01

    Systemins and their hydroxyproline-rich glycopeptide systemin (ppHS) subfamily members are known to mediate antiherbivore defenses in some solanaceous taxa but not others; functions other than in defense remain largely unexplored. Nicotiana attenuata's ppHS is known not to function in herbivore defense. NappHS transcripts are abundant in flowers, particularly in pistils, and when two N. attenuata accessions from Utah and Arizona were transformed to silence NappHS by RNAi (IRsys), seed capsule production and seed number per capsule were reduced in both accessions. These reductions in reproductive performance could not be attributed to impaired pollen or ovule viability; hand-pollination of all IRsys lines of both accessions restored seed production per capsule to levels found in wild-type plants. Rather, changes in flower morphology that decreased the efficiency of self-pollination are likely responsible: IRsys plants of both accessions have flowers with pistils that protrude beyond their anthers. Because these changes in flower morphology are reminiscent of CORONATINE-INSENSITIVE1-silenced N. attenuata plants, we measured jasmonates (JAs) and their biosynthetic transcripts in different floral developmental stages, and found levels of JA-isoleucine (Ile)/leucine and threonine deaminase transcripts, which are abundant in wild-type pistils, to be significantly reduced in IRsys buds and flowers. Threonine deaminase supplies Ile for JA-Ile biosynthesis, and we propose that ppHS mediates JA signaling during flower development and thereby changes flower morphology. These results suggest that the function of ppHS family members in N. attenuata may have diversified to modulate flower morphology and thereby outcrossing rates in response to biotic or abiotic stresses. PMID:19211701

  13. The Role of Access to Head Start and Quality Ratings for Spanish-Speaking Dual Language Learners’ (DLLs) Participation in Early Childhood Education

    PubMed Central

    2014-01-01

    Data from the Head Start Impact Study (N = 4,442) were used to test for differences between Spanish-speaking Dual Language Learners (DLLs) and monolingual English-speaking children in: (1) Head Start attendance rates when randomly assigned admission; and (2) quality ratings of other early childhood education (ECE) programs attended when not randomly assigned admission to Head Start. Logistic regressions showed that Spanish-speaking DLL children randomly assigned a spot in Head Start were more likely than monolingual-English learners to attend. Further, Spanish-speaking DLLs not randomly assigned a spot in Head Start were more likely to attend higher-quality ECE centers than non-DLL children. Policy implications are discussed, suggesting that, if given access, Spanish-speaking DLL families will take advantage of quality ECE programs. PMID:25018585

  14. One-Stage vs. Two-Stage Brachio-Basilic Arteriovenous Fistula for Dialysis Access: A Systematic Review and a Meta-Analysis

    PubMed Central

    Bashar, Khalid; Healy, Donagh A.; Elsheikh, Sawsan; Browne, Leonard D.; Walsh, Michael T.; Clarke-Moloney, Mary; Burke, Paul E.; Kavanagh, Eamon G.; Walsh, Stewart R.

    2015-01-01

    Introduction A brachiobasilic arteriovenous fistula (BB-AVF) can provide access for haemodialysis in patients who are not eligible for a more superficial fistula. However, it is unclear whether one- or two-stage BB-AVF is the best option for patients. Aim To systematically assess the difference between both procedures in terms of access maturation, patency and postoperative complications. Methods Online search for randomised controlled trials (RCTs) and observational studies that compared the one-stage versus the two-stage technique for creating a BB-AVF. Results Eight studies were included (849 patients with 859 fistulas), 366 created using a one-stage technique, while 493 in a two-stage approach. There was no statistically significant difference between the two groups in the rate of successful maturation (Pooled risk ratio = 0.95 [0.82, 1.11], P = 0.53). Similarly, the incidence of postoperative haematoma (Pooled risk ratio = 0.73 [0.34, 1.58], P = 0.43), wound infection (Pooled risk ratio = 0.77 [0.35, 1.68], P = 0.51) and steal syndrome (Pooled risk ratio = 0.65 [0.27, 1.53], P = 0.32) were statistically comparable. Conclusion Although more studies seem to favour the two-stage BVT approach, evidence in the literature is not sufficient to draw a final conclusion as the difference between the one-stage and the two-stage approaches for creation of a BB-AVF is not statistically significant in terms of the overall maturation rate and postoperative complications. Patency rates (primary, assisted primary and secondary) were comparable in the majority of studies. Large randomised properly conducted trials with superior methodology and adequate sub-group analysis are needed before making a final recommendation. PMID:25751655

  15. RAVECAB: improving outcome in off-pump minimal access surgery with robotic assistance and video enhancement

    PubMed Central

    Boyd, W. Douglas; Kiaii, Bob; Novick, Richard J.; Rayman, Reiza; Ganapathy, Sugantha; Dobkowski, Wojciech B.; Jablonsky, George; McKenzie, F. Neil; Menkis, Alan H.

    2001-01-01

    Objective To determine the efficacy of using the harmonic scalpel and robotic assistance to facilitate thoracoscopic harvest of the internal thoracic artery (ITA). Design A case series. Setting London Health Sciences Centre, University of Western Ontario, London, Ont. Patients and methods Fifteen consecutive patients requiring harvest of the ITA for coronary artery bypass grafting. Intervention Robot-assisted, video-enhanced coronary artery bypass (RAVECAB) through limited-access incisions, using the harmonic scalpel and a voice-activated robotic assistant. Main outcome measures Ease and duration of the harvesting technique, complications of the procedure, graft flow and patency, and duration of postoperative hospitalization. Results RAVE-CAB facilitated thoracoscopic dissection of the ITA with the harmonic scalpel in all cases. There were no conversions to a standard approach and no reoperations for bleeding. The mean (and standard deviation) ITA harvest time was 64.1 (22.9) minutes (range from 40 to 118 minutes). Robotic voice command capture rate was greater than 95%. Mean (and SD) intraoperative graft flows were 33.1 (26.8) mL/min (range from 14 to 126 mL/min). There was 100% graft patency on postoperative angiography. There were no deaths, perioperative myocardial infarction or arrhythmias. Mean (and SD) postoperative hospitalization was 3.3 (0.8) days. Conclusions RAVECAB is a demanding procedure that addresses many of the disadvantages of the “conventional” minimally invasive coronary artery bypass. It allows complete pedicle dissection with minimal ITA manipulation and assures sufficient conduit length and a tension-free coronary artery anastomosis. All anastomoses were performed under direct vision through a 5- to 8-cm inferior mammary incision. PMID:11220798

  16. Role of the nitric oxide-cGMP system in the regulation of ductus arteriosus patency in fetal rats.

    PubMed

    Takizawa, T; Horikoshi, E; Kamata, A

    1999-12-01

    The purpose of this study was to examine the role of the nitric oxide (NO) and cyclic guanosine monophosphate (cGMP) system in the regulation of the ductus arteriosus (DA) patency in fetal rats. Pregnant rats were administered N(G)-nitro-L-arginine methyl ester (L-NAME, 50 mg/kg, ip), an NO synthase (NOS) inhibitor; methylene blue (30, 50 and 100 mg/kg, ip), a soluble guanylate cyclase inhibitor; or indomethacin (3 mg/kg, po), a cyclooxygenase inhibitor, at various times before cesarean section. Dams were decapitated to obtain the fetuses by cesarean section, and fetuses were rapidly frozen in an acetone-dry ice mixture. Using rapid freezing and shaving methods, the calibers of the DA, pulmonary artery (PA) and descending aorta (Ao) were measured to evaluate the effects of treatment. L-NAME reduced the DA calibers to 86% of the initial values, but recovery to the control levels occurred 6 hr after the injection. Indomethacin decreased the DA calibers to 34% of the control values and sustained the DA constriction until 24 hr after the treatment. Methylene blue caused DA constriction to almost the same degree as indomethacin, but the levels normalized within 24 hr after the treatment. We conclude that L-NAME caused a slight constriction of the DA, whereas methylene blue and indomethacin caused marked constriction of the vessels, suggesting that the NO-cGMP system as well as prostaglandins contribute to the DA patency. PMID:10651046

  17. MRI-Monitored Intra-Shunt Local Agent Delivery of Motexafin Gadolinium: Towards Improving Long-Term Patency of TIPS

    PubMed Central

    Meng, Yanfeng; Zhang, Tong; Willis, Patrick; Le, Thomas; Soriano, Stephanie; Ray, Erik; Valji, Karim; Zhang, Guixiang; Yang, Xiaoming

    2013-01-01

    Background Transjugular intrahepatic portosystemic shunt (TIPS) has become an important and effective interventional procedure in treatment of the complications related to portal hypertension. Although the primary patency of TIPS has been greatly improved due to the clinical application of cover stent-grafts, the long-term patency is still suboptimal. This study was to investigate the feasibility of using magnetic resonance imaging (MRI)-monitored intra-shunt local agent delivery of motexafin gadolinium (MGd) into shunt-vein walls of TIPS. This new technique aimed to ultimately inhibit shuntstenosis of TIPS. Methodology Human umbilical vein smooth muscle cells (SMCs) were incubated with various concentrations of MGd, and then examed by confocal microscopy and T1-map MRI. In addition, the proliferation of MGd-treated cells was evaluated. For in vivo validation, seventeen pigs underwent TIPS. Before placement of the stent, an MGd/trypan-blue mixture was locally delivered, via a microporous balloon, into eleven shunt-hepatic vein walls under dynamic MRI monitoring, while trypan-blue only was locally delivered into six shunt-hepatic vein walls as serve as controls. T1-weighted MRI of the shunt-vein walls was achieved before- and at different time points after agent injections. Contrast-to-noise ratio (CNR) of the shunt-vein wall at each time-point was measured. Shunts were harvested for subsequent histology confirmation. Principal Findings In vitro studies confirmed the capability of SMCs in uptaking MGds in a concentration-dependent fashion, and demonstrated the suppression of cell proliferation by MGds as well. Dynamic MRI displayed MGd/blue penetration into the shunt-vein walls, showing significantly higher CNR of shunt-vein walls on post-delivery images than on pre-delivery images (49.5±9.4 vs 11.2±1.6, P<0.01), which was confirmed by histology. Conclusion Results of this study indicate that MRI-monitored intra-shunt local MGd delivery is feasible and MGd

  18. The reverse J arteriovenous graft configuration for hemodialysis access: rationale, technique, and outcomes.

    PubMed

    Cull, David L; Carsten, Christopher G; Kalbaugh, Corey A; York, John W; Campbell, Ted R; Cass, Anna L; Taylor, Spence M

    2008-07-01

    The long-term survival of patients on hemodialysis is often limited by the exhaustion of vascular access sites. A fundamental principle of vascular access surgery is that the arteriovenous (AV) access be placed as far distally in the arm as possible. This principle enhances the secondary patency of the AV grafts by preserving the proximal veins for AV graft revision and provides venous outflow for a new AV access to be placed more proximally in the extremity. The standard straight and looped AV graft configurations violate this principle by bypassing long segments of vein in the extremity that could be used for AV graft revision or new AV graft placement. We have developed a novel AV graft configuration that preserves venous outflow and enhances the longevity of each AV access site. The purpose of this review is to describe the reverse J AV graft technique and to report our outcomes with the procedure. Between February 2004 and April 2007, 26 AV grafts were placed using the reverse J configuration. Eighteen (69%) AV grafts were placed in the upper arm, 7 (27%) were placed in the forearm, and 1 (4%) was placed in the thigh. Median follow-up was 320 days. The secondary AV graft patency was 90 per cent at 6 months, 84 per cent at 12 months, and 84 per cent at 18 months. Five AV grafts were subsequently revised to a loop configuration. Overall patient survival was 85 per cent at 6 months, 68 per cent at 12 months, and 62 per cent at 18 months. Compared with the standard straight and looped AV graft configurations, the reverse J AV graft configuration preserves the length of venous outflow in the extremity for AV graft revision or new AV graft placement. Therefore, the reverse J configuration enhances the secondary patency of AV graft patency and AV access site longevity. PMID:18646480

  19. Influence of cooling rate in planar thermally assisted magnetic random access memory: Improved writeability due to spin-transfer-torque influence

    SciTech Connect

    Chavent, A.; Ducruet, C.; Portemont, C.; Creuzet, C.; Alvarez-Hérault, J.; Vila, L.; Sousa, R. C.; Prejbeanu, I. L.; Dieny, B.

    2015-09-14

    This paper investigates the effect of a controlled cooling rate on magnetic field reversal assisted by spin transfer torque (STT) in thermally assisted magnetic random access memory. By using a gradual linear decrease of the voltage at the end of the write pulse, the STT decays more slowly or at least at the same rate as the temperature. This condition is necessary to make sure that the storage layer magnetization remains in the desired written direction during cooling of the cell. The influence of the write current pulse decay rate was investigated on two exchange biased synthetic ferrimagnet (SyF) electrodes. For a NiFe based electrode, a significant improvement in writing reproducibility was observed using a gradual linear voltage transition. The write error rate decreases by a factor of 10 when increasing the write pulse fall-time from ∼3 ns to 70 ns. For comparison, a second CoFe/NiFe based electrode was also reversed by magnetic field assisted by STT. In this case, no difference between sharp and linear write pulse fall shape was observed. We attribute this observation to the higher thermal stability of the CoFe/NiFe electrode during cooling. In real-time measurements of the magnetization reversal, it was found that Ruderman-Kittel-Kasuya-Yosida (RKKY) coupling in the SyF electrode vanishes for the highest pulse voltages that were used due to the high temperature reached during write. As a result, during the cooling phase, the final state is reached through a spin-flop transition of the SyF storage layer.

  20. Influence of cooling rate in planar thermally assisted magnetic random access memory: Improved writeability due to spin-transfer-torque influence

    NASA Astrophysics Data System (ADS)

    Chavent, A.; Ducruet, C.; Portemont, C.; Creuzet, C.; Vila, L.; Alvarez-Hérault, J.; Sousa, R. C.; Prejbeanu, I. L.; Dieny, B.

    2015-09-01

    This paper investigates the effect of a controlled cooling rate on magnetic field reversal assisted by spin transfer torque (STT) in thermally assisted magnetic random access memory. By using a gradual linear decrease of the voltage at the end of the write pulse, the STT decays more slowly or at least at the same rate as the temperature. This condition is necessary to make sure that the storage layer magnetization remains in the desired written direction during cooling of the cell. The influence of the write current pulse decay rate was investigated on two exchange biased synthetic ferrimagnet (SyF) electrodes. For a NiFe based electrode, a significant improvement in writing reproducibility was observed using a gradual linear voltage transition. The write error rate decreases by a factor of 10 when increasing the write pulse fall-time from ˜3 ns to 70 ns. For comparison, a second CoFe/NiFe based electrode was also reversed by magnetic field assisted by STT. In this case, no difference between sharp and linear write pulse fall shape was observed. We attribute this observation to the higher thermal stability of the CoFe/NiFe electrode during cooling. In real-time measurements of the magnetization reversal, it was found that Ruderman-Kittel-Kasuya-Yosida (RKKY) coupling in the SyF electrode vanishes for the highest pulse voltages that were used due to the high temperature reached during write. As a result, during the cooling phase, the final state is reached through a spin-flop transition of the SyF storage layer.

  1. Drug-Related Arrest Rates and Spatial Access to Syringe Exchange Programs in New York City Health Districts: Combined Effects on the Risk of Injection-Related Infections among Injectors

    PubMed Central

    Jarlais, Don C Des; Tempalski, Barbara; Bossak, Brian H; Ross, Zev; Friedman, Samuel R

    2011-01-01

    Drug-related law enforcement activities may undermine the protective effects of syringe exchange programs (SEPs) on local injectors’ risk of injection-related infections. We explored the spatial overlap of drug-related arrest rates and access to SEPs over time (1995-2006) in New York City health districts, and used multilevel models to investigate the relationship of these two district-level exposures to the odds of injecting with an unsterile syringe. Districts with better SEP access had higher arrest rates, and arrest rates undermined SEPs’ protective relationship with unsterile injecting. Drug-related enforcement strategies targeting drug users should be de-emphasized in areas surrounding SEPs. PMID:22047790

  2. Influence of endothelial cell seeding on platelet deposition and patency in small-diameter Dacron arterial grafts

    SciTech Connect

    Allen, B.T.; Long, J.A.; Clark, R.E.; Sicard, G.A.; Hopkins, K.T.; Welch, M.J.

    1984-01-01

    Serial platelet deposition, surface topography, and patency were evaluated in control (N . 28) and endothelial cell-seeded (N . 28) small-diameter (4 mm inner diameter) USCI Dacron grafts implanted in the carotid and femoral arteries of dogs. All dogs received aspirin (325 mg) daily for 2 weeks starting 24 hours prior to graft implantation. Endothelial cell seeding was performed by mixing suspensions of autologous endothelial cells that had been enzymatically harvested from segments of external jugular vein with blood that was used to preclot the prostheses. The platelet deposition on each graft was quantitated by means of indium 111-labeled platelets and technetium 99m-labeled red cells in a dual-isotope platelet-imaging technique. Platelet deposition on seeded grafts 24 hours after implantation was significantly higher than on the controls (p less than 0.05). Two weeks after implantation platelet deposition on seeded prostheses had decreased to a level significantly lower than that on the controls and continued to decline on serial studies up to 7 months. In contrast to seeded grafts, platelet accumulation on control grafts dramatically increased after the withdrawal of aspirin therapy and was associated with a sharp rise in control graft thromboses. Cumulative 7-month patency for seeded prostheses was significantly higher than for the controls (96% and 29%, respectively; p less than 0.001). We conclude that endothelial cell seeding in combination with short-term aspirin therapy is a simple, reliable diameter Dacron prostheses. Abrupt withdrawal of aspirin therapy may be contraindicated in nonseeded control grafts because it results in increased platelet deposition and thrombosis.

  3. External-to-Internal Iliac Stent-Graft: Medium-Term Patency Following Exclusion of a Retrogradely Perfused Common Iliac Aneurysm

    SciTech Connect

    Nicholls, Marcus John; McPherson, Simon

    2010-08-15

    Following complicated aortic aneurysm surgery a complete left iliac occlusion resulted in buttock claudication. A retrogradely perfused right common iliac aneurysm expanded. Exclusion was by external-to-internal iliac stent-graft. No deterioration in claudication occurred with medium-term stent-graft patency.

  4. Factors Associated With Infarct-Related Artery Patency Before Primary Percutaneous Coronary Intervention for ST-Elevation Myocardial Infarction (from the FAST-MI 2010 Registry).

    PubMed

    Bailleul, Clotilde; Puymirat, Etienne; Aissaoui, Nadia; Schiele, François; Ducrocq, Gregory; Coste, Pierre; Blanchard, Didier; Brasselet, Camille; Elbaz, Meyer; Steg, Philippe Gabriel; Le Breton, Hervé; Bonnefoy-Cudraz, Eric; Montalescot, Gilles; Cottin, Yves; Goldstein, Patrick; Ferrières, Jean; Simon, Tabassome; Danchin, Nicolas

    2016-01-01

    Early infarct-related artery (IRA) patency is associated with better clinical outcomes in patients with ST-elevation myocardial infarction (STEMI). Using the French Registry of ST-elevation and non-ST-elevation Myocardial Infarction (FAST-MI) 2010 registry, we investigated factors related to IRA patency (thrombolysis in myocardial infarction [TIMI] 2/3 flow) at the start of procedure in patients admitted for primary percutaneous coronary intervention. FAST-MI 2010 is a nationwide French registry including 4,169 patients with acute MI. Of 1,452 patients with STEMI with primary percutaneous coronary intervention, 466 (32%) had TIMI 2/3 flow of IRA before the procedure. Mean age (62 ± 14 years in both groups), Global Registry of Acute Coronary Event score (141 ± 31 vs 142 ± 34), and time from onset to angiography (472 ± 499 vs 451 ± 479 minutes) did not differ according to IRA patency (TIMI 2/3 vs TIMI 0/1). Using multivariate logistic regression analysis, IRA patency was more frequently found in patients having called earlier (time from onset to electrocardiogram [ECG] <120 minutes; odds ratio [OR] 1.49; 95% confidence interval [CI] 1.17 to 1.89), or receiving rapid-onset of action (prasugrel or glycoprotein IIb-IIIa) antiplatelet therapy in the prehospital setting (OR 1.59, 95% CI 1.14 to 2.21). Increasing time from diagnostic ECG to angiography was also associated with IRA patency (>90 minutes; OR 1.37, 95% CI 1.08 to 1.75). In conclusion, preprocedural IRA patency is observed in one third of patients with STEMI, it is more frequently found in patients having received fast-acting antiplatelet therapy before angiography, and in patients having called early. Higher IRA patency with increasing time delays from qualifying ECG to angiography suggests an additional role of spontaneous or medication-mediated fibrinolysis. PMID:26541905

  5. Correlation of anomalous write error rates and ferromagnetic resonance spectrum in spin-transfer-torque-magnetic-random-access-memory devices containing in-plane free layers

    SciTech Connect

    Evarts, Eric R.; Rippard, William H.; Pufall, Matthew R.; Heindl, Ranko

    2014-05-26

    In a small fraction of magnetic-tunnel-junction-based magnetic random-access memory devices with in-plane free layers, the write-error rates (WERs) are higher than expected on the basis of the macrospin or quasi-uniform magnetization reversal models. In devices with increased WERs, the product of effective resistance and area, tunneling magnetoresistance, and coercivity do not deviate from typical device properties. However, the field-swept, spin-torque, ferromagnetic resonance (FS-ST-FMR) spectra with an applied DC bias current deviate significantly for such devices. With a DC bias of 300 mV (producing 9.9 × 10{sup 6} A/cm{sup 2}) or greater, these anomalous devices show an increase in the fraction of the power present in FS-ST-FMR modes corresponding to higher-order excitations of the free-layer magnetization. As much as 70% of the power is contained in higher-order modes compared to ≈20% in typical devices. Additionally, a shift in the uniform-mode resonant field that is correlated with the magnitude of the WER anomaly is detected at DC biases greater than 300 mV. These differences in the anomalous devices indicate a change in the micromagnetic resonant mode structure at high applied bias.

  6. Item response theory analysis of the Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised in the Pooled Resource Open-Access ALS Clinical Trials Database.

    PubMed

    Bacci, Elizabeth D; Staniewska, Dorota; Coyne, Karin S; Boyer, Stacey; White, Leigh Ann; Zach, Neta; Cedarbaum, Jesse M

    2016-01-01

    Our objective was to examine dimensionality and item-level performance of the Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised (ALSFRS-R) across time using classical and modern test theory approaches. Confirmatory factor analysis (CFA) and Item Response Theory (IRT) analyses were conducted using data from patients with amyotrophic lateral sclerosis (ALS) Pooled Resources Open-Access ALS Clinical Trials (PRO-ACT) database with complete ALSFRS-R data (n = 888) at three time-points (Time 0, Time 1 (6-months), Time 2 (1-year)). Results demonstrated that in this population of 888 patients, mean age was 54.6 years, 64.4% were male, and 93.7% were Caucasian. The CFA supported a 4* individual-domain structure (bulbar, gross motor, fine motor, and respiratory domains). IRT analysis within each domain revealed misfitting items and overlapping item response category thresholds at all time-points, particularly in the gross motor and respiratory domain items. Results indicate that many of the items of the ALSFRS-R may sub-optimally distinguish among varying levels of disability assessed by each domain, particularly in patients with less severe disability. Measure performance improved across time as patient disability severity increased. In conclusion, modifications to select ALSFRS-R items may improve the instrument's specificity to disability level and sensitivity to treatment effects. PMID:26473473

  7. [Application of ultrasonography in central venous catheterization; access sites and procedure techniques].

    PubMed

    Czyzewska, Dorota; Ustymowicz, Andrzej; Klukowski, Mark

    2016-08-01

    Central venous catheterization is commonly performed in clinical practice. Traditional procedural technique is based on anatomical landmarks, but is associated with a high risk of failure and complications. To decrease their incidence European and American societies recommend application of ultrasonography. Preliminary ultrasonographic examination allows for assessment of local anatomical relations as well as vessel morphology (diameter, patency), while real-time ultrasonography increases chances of successful needle insertion. This paper presents the most common venous access sites and procedure techniques. PMID:27157792

  8. Permanent pacing in patients without upper limb venous access: a review of current techniques

    PubMed Central

    Seow, Swee-Chong; Lim, Toon-Wei; Singh, Devinder; Yeo, Wee-Tiong; Kojodjojo, Pipin

    2014-01-01

    Permanent transvenous cardiac pacing is usually accomplished through the upper limb veins. When these are occluded, several other vascular access options exist which include the internal jugular, external jugular, femoral and iliac veins as well as more proximal access of the subclavian veins. Anterograde and retrograde techniques to restore subclavian venous patency has been described. A review of these approaches is undertaken, with a discussion of their pros and cons. Familiarity with these techniques will enable the implanter to perform transvenous pacing when faced with limited vascular access. PMID:27326197

  9. Increased access rate to a primary health-care centre by introducing a structured patient sorting system developed to make the most efficient use of the personnel: a pilot study.

    PubMed

    Thorn, Jörgen; Maun, Andy; Bornhöft, Lena; Kornbakk, Malena; Wedham, Sofia; Zaffar, Mona; Thanner, Cathrine

    2010-11-01

    The primary health-care centre (PHCC) participating in the study has had financial problems for several years and it has been particularly difficult to recruit general practitioners (GPs). As a result, the access rate to the PHCC was low. The purpose of this study was to increase the access rate to the PHCC and to make the most efficient use of the staff by introducing a structured patient sorting system. All personnel were involved in the implementation process and participated regularly in interdisciplinary work-groups. A variety of Drop-in receptions were created and a manual for sorting patients by condition was introduced. The main finding was that the total access rate to the PHCC increased by 27% and that each staff member increased their personal access rate by an average of 13%. Eighty-three percent of the patients who were initially treated by the rehabilitation team were treated solely by the team and did not need to see a GP. No medical backlashes were reported. These findings indicate a more efficient use of the personnel. Furthermore, both personnel and patients indicated an improvement in the possibility to book patient appointments after the introduction of the structured patient sorting system. PMID:21097727

  10. Laser-driven short-duration heating angioplasty: chronic artery lumen patency and histology in porcine iliac artery

    NASA Astrophysics Data System (ADS)

    Shimazaki, Natsumi; Kunio, Mie; Naruse, Sho; Arai, Tsunenori; Sakurada, Masami

    2012-02-01

    We proposed a short-duration heating balloon angioplasty. We designed a prototype short-duration heating balloon catheter that can heat artery media to 60-70°C within 15-25 s with a combination of laser-driven heat generation and continuous fluid irrigation in the balloon. The purpose of this study was to investigate chronic artery lumen patency as well as histological alteration of artery wall after the short-duration heating balloon dilatation with porcine healthy iliac artery. The short-term heating balloon dilated sites were angiographically patent in acute (1 hour) and in chronic phases (1 and 4 weeks). One week after the dilatation, smooth muscle cells (SMCs) density in the artery media measured from H&E-stained specimens was approx. 20% lower than that in the reference artery. One and four weeks after the dilatations, normal structure of artery adventitia was maintained without any incidence of thermal injury. Normal lamellar structure of the artery media was also maintained. We found that the localized heating restricted to artery media by the short-duration heating could maintain adventitial function and artery normal structure in chronic phase.

  11. In vivo argon laser vascular welding using thermal feedback: open and closed loop patency and collagen crosslinking

    SciTech Connect

    Small, W., LLNL

    1997-02-28

    An in vivo study of vascular welding with a fiber-delivered argon laser was conducted using a canine model. Longitudinal arteriotomies and venotomies were treated on femoral vein and artery. Laser energy was delivered to the vessel wall via a 400 {micro}m optical fiber. The surface temperature at the center of the laser spot was monitored in real time using a hollow glass optical fiber-based two-color infrared thermometer. The surface temperature was limited by either a room-temperature saline drip or direct feedback control of the laser using a mechanical shutter to alternately pass and block the laser. Acute patency was evaluated either visually (leak/no leak) or by in vivo burst pressure measurements. Biochemical assays were performed to investigate the possible laser-induced formation or destruction of enzymatically mediated covalent crosslinks between collagen molecules. Viable welds were created both with and without the use of feedback control. Tissues maintained at 50 C using feedback control had an elevated crosslink count compared to controls, while those irradiated without feedback control experienced a decrease. Differences between the volumetric heating associated with open and closed loop protocols may account for the different effects on collagen crosslinks. Covalent mechanisms may play a role in argon laser vascular fusion.

  12. Clinical Experience with the PillCam Patency Capsule prior to Video Capsule Endoscopy: A Real-World Experience.

    PubMed

    Römmele, C; Brueckner, J; Messmann, H; Gölder, S K

    2016-01-01

    Background. In patients with known or suspected risk factors for gastrointestinal stenosis, the PillCam patency capsule (PC) is given before a video capsule endoscopy (VCE) in order to minimize the risk of capsule retention (CR). CR is considered unlikely upon excretion of the PC within 30 hours, excretion in an undamaged state after 30 hours, or radiological projection to the colon. Methods. We performed a retrospective analysis of 38 patients with risk factors for CR, who received a PC from 02/2013 to 04/2015 at Klinikum Augsburg. Results. Sixteen of our 38 patients observed a natural excretion after a mean time of 34 hours past ingestion. However, only 8 patients observed excretion within 30 hours, as recommended by the company. In 20 patients passage of the PC into the colon was shown via RFID-scan or radiological imaging (after 33 and 45 hours, resp.). Only 2 patients showed a pathologic PC result. In consequence, 32 patients received the VCE; no CR was observed. Conclusion. Our data indicates that a VCE could safely be performed even if the PC excretion time is longer than 30 hours and the excreted PC was not screened for damage. PMID:26880902

  13. Predictors of preinterventional patency of infarct-related artery in patients with ST-segment elevation myocardial infarction: Importance of neutrophil to lymphocyte ratio and uric acid level

    PubMed Central

    Şahin, Durmuş Yıldıray; Gür, Mustafa; Elbasan, Zafer; Yıldız, Ali; Kaya, Zekeriya; İçen, Yahya Kemal; Kıvrak, Ali; Türkoğlu, Caner; Yılmaz, Remzi; Çaylı, Murat

    2013-01-01

    BACKGROUND: Patients with ST-segment elevation myocardial infarction (STEMI) and a patent infarct-related artery (IRA) experience lower mortality and better clinical outcome, but little is known about the predictors of IRA patency before primary percutaneous coronary intervention (PCI) in the setting of STEMI. OBJECTIVE: To assess possible predictors of patency of IRA before primary PCI in patients with STEMI. METHODS: A total of 880 patients with STEMI undergoing primary PCI were prospectively included (646 male, 234 female; mean [± SD] age 58.5±12.4 years). Blood samples were obtained on admission to investigate biochemical markers. Preinterventional thrombolysis in myocardial infarction (TIMI) flow was assessed in all patients. The patients were divided into two groups according to the pre-PCI TIMI flow as impaired flow group (TIMI flow 0, 1 and 2) and normal flow group (TIMI flow 3). Transthoracic echocardiography was performed in all patients. RESULTS: Eighty-three (9.43%) patients had pre-PCI TIMI 3 flow in IRA. Uric acid levels and neutrophil to lymphocyte (N to L) ratio in the normal flow group were lower than in the impaired flow group (P<0.001 for both). However, ejection fraction (EF) was higher in the normal flow group than in the impaired flow group. Multivariate logistic regression analysis showed that IRA patency was independently associated with serum uric acid level (β 0.673 [95% CI 0.548 to 0.826]; P<0.001), N to L ratio (β 0.783 [95% CI 0.683 to 0.897]; P<0.001) and EF (β 1.033 [95% CI 1.006 to 1.061]; P=0.016). CONCLUSION: Serum uric acid level, N to L ratio and EF are independent predictors of the pre-PCI patency of IRA in patients with STEMI undergoing primary PCI. PMID:23940451

  14. Web Accessibility and Accessibility Instruction

    ERIC Educational Resources Information Center

    Green, Ravonne A.; Huprich, Julia

    2009-01-01

    Section 508 of the Americans with Disabilities Act (ADA) mandates that programs and services be accessible to people with disabilities. While schools of library and information science (SLIS*) and university libraries should model accessible Web sites, this may not be the case. This article examines previous studies about the Web accessibility of…

  15. Impact of intravascular ultrasound findings on long-term patency after self-expanding nitinol stent implantation in the iliac artery lesion.

    PubMed

    Miki, Kojiro; Fujii, Kenichi; Fukunaga, Masashi; Nishimura, Machiko; Horimatsu, Tetsuo; Saita, Ten; Tamaru, Hiroto; Imanaka, Takahiro; Shibuya, Masahiko; Naito, Yoshiro; Masuyama, Tohru

    2016-04-01

    Although intravascular ultrasound (IVUS) predictors of stent patency for the coronary artery lesion have been established, little is known about IVUS predictors of stent patency for the aorto-iliac artery lesion. We analyzed 154 lesions of 122 patients who underwent stent implantation for iliac artery lesions. Quantitative and qualitative IVUS analyses were performed for pre- and post-procedural IVUS imaging in all lesions. Target lesion revascularization (TLR) was defined as clinically driven revascularization with >50 % angiographic stenosis of the target lesion. The mean follow-up period was 39 ± 16 months. TLRs were performed in 13 lesions (8.4 %). Post-procedural minimum stent area (MSA) was significantly smaller in the TLR group compared to the no-TLR group (16.0 ± 5.8 vs. 25.6 ± 8.5 mm(2), p < 0.001). Stent edge dissection was frequently observed in the TLR group compared to the no-TLR group (53.8 vs. 24.1 %, p = 0.04). Multivariate analysis revealed that post-procedural MSA (OR = 0.76, p < 0.01) and stent edge dissection (OR = 10.4, p < 0.01) were independent IVUS predictors of TLR. Receiver-operating characteristic analysis identified post-procedural MSA <17.8 mm(2) as the optimal cut-point for the prediction of TLR (AUC = 0.846). Post-procedural MSA and stent edge dissection could predict long-term stent patency in the iliac artery lesion. Our results propose that adequate stent enlargement without edge dissection might be important to reduce TLR in the iliac artery lesion. PMID:25605656

  16. Sequential oogenesis is controlled by an oviduct factor in the locusts Locusta migratoria and Schistocerca gregaria: Overcoming the doctrine that patency in follicle cells is induced by juvenile hormone.

    PubMed

    Seidelmann, Karsten; Helbing, Cornelia; Göbeler, Norman; Weinert, Heike

    2016-07-01

    In insects that lay eggs in large clutches, yolk accumulation in each of the many ovarioles is restricted to the basal (terminal) oocyte, the one closest to the lateral oviduct. All succeeding (subterminal) oocytes remain small until the terminal oocytes finished their development and were ovulated into the oviduct. The major step regulating yolk uptake by terminal oocytes is the formation of gaps between cells of the follicle layer, a process termed patency. In the migratory as well as in the desert locust, patency is induced by a Patency Inducing Factor (PIF) produced by the lateral oviducts. PIF is secreted in all regions of the lateral oviducts and interacts with the basal follicle cells via the pedicel, a fine duct that connects an ovariole with the oviduct. By this mechanism, patency is triggered in the follicle cells of the terminal oocyte only, restricting yolk accumulation to the oocytes next to ovulation. In contrast to the previous hypothesis, juvenile hormone (JH) is not necessary to induce patency, rather JH amplifies the effect of PIF. PMID:27040271

  17. Open Access

    ERIC Educational Resources Information Center

    Suber, Peter

    2012-01-01

    The Internet lets us share perfect copies of our work with a worldwide audience at virtually no cost. We take advantage of this revolutionary opportunity when we make our work "open access": digital, online, free of charge, and free of most copyright and licensing restrictions. Open access is made possible by the Internet and copyright-holder…

  18. Access Denied

    ERIC Educational Resources Information Center

    Villano, Matt

    2008-01-01

    Building access control (BAC)--a catchall phrase to describe the systems that control access to facilities across campus--has traditionally been handled with remarkably low-tech solutions: (1) manual locks; (2) electronic locks; and (3) ID cards with magnetic strips. Recent improvements have included smart cards and keyless solutions that make use…

  19. Selective inhibition of factor Xa during thrombolytic therapy markedly improves coronary artery patency in a canine model of coronary thrombosis.

    PubMed

    Nicolini, F A; Lee, P; Malycky, J L; Lefkovits, J; Kottke-Marchant, K; Plow, E F; Topol, E J

    1996-01-01

    +/- 5 ng/ml respectively; both P < 0.05 vs saline). Scanning electron microscopy of coronary arteries showed residual thrombi with intense platelet and fibrin deposition adherent to the deendothelialized surface of the vessels following saline and hirudin therapy. In contrast, TAP-treated arteries were characterized by the absence of fibrin and minimal platelet deposition. In conclusion, these hemodynamic, biochemical and morphologic data suggest that adjunctive treatment with a higher tier blockade of the coagulation cascade is superior to direct thrombin inhibition in maintaining coronary artery patency following thrombolysis in the experimental canine electrolytic model. These findings highlight the potential adverse effects of unchecked thrombin generation in the setting of thrombolytic therapy. PMID:8845461

  20. [Indices of intraoperative flowmetry, determining patency of grafts in the remote period after revascularization of the right coronary artery].

    PubMed

    Bazylev, V V; Nemchenko, E V; Pavlov, A A; Karnakhin, V A

    2016-01-01

    % with the index of resistance in the I-graft from 3.2. The conclusion was made that composite T-grafts and combined I-grafts demonstrated similar results of patency within the terms up to 3 years, possessing advantages over autovenous conduits while shunting the RCA basin. The optimal index of peripheral resistance for the autovein during revascularization of the RCA basin is up to 2.9; for the combined T-graft - up to 3.2, and for the composite T-graft - up to 4.0. Probability of shunt occlusion in the remote period does not depend upon the average volumetric blood velocity (Qmean) but is directly proportional to the value of the pulsatility index (Pi) which reflects the state of the distal bed. PMID:27336335

  1. Near-Infrared Imaging for the Assessment of Anastomotic Patency, Thrombosis, and Reperfusion in Microsurgery: A Pilot Study in a Porcine Model

    PubMed Central

    Vargas, Christina R.; Nguyen, John T.; Ashitate, Yoshitomo; Silvestre, Jason; Venugopal, Vivek; Neacsu, Florin; Kettenring, Frank; Frangioni, John V.; Gioux, Sylvain; Lee, Bernard T.

    2015-01-01

    Background Advances in microsurgical techniques have increased the use of free tissue transfer. Methods of intraoperative flap perfusion assessment, however, still rely primarily on subjective evaluation of traditional clinical parameters. Anastomotic thrombosis, if not expeditiously identified and revised, can result in flap loss with significant associated morbidity. This study aims to evaluate the use of near-infrared (NIR) fluorescence imaging in the assessment of microsurgical anastomotic patency, thrombosis, and vascular revision. Materials and Methods A model of pedicle thrombosis was created using bilateral abdominal flaps isolated on deep superior epigastric vascular pedicles in four Yorkshire pigs. Following flap elevation, microvascular arterial and venous anastomoses were performed unilaterally, preserving an intact contralateral control flap. Thrombosis was induced at the arterial anastomosis site using ferric chloride, and both flaps imaged using NIR fluorescence angiography. The thrombosed vascular segments were subsequently excised and new anastomoses performed to restore flow. Follow-up imaging of both flaps was then obtained to confirm patency using fluorescence imaging technology. Results Pedicled abdominal flaps were created and successful anastomotic thrombosis was induced unilaterally in each pig. Fluorescence imaging technology identified large decreases in tissue perfusion of the thrombosed flap within 2 minutes. After successful revision anastomosis, NIR imaging demonstrated dramatic increase in flow to the reconstructed flap, but intensity did not return to pre-thrombosis levels. Conclusions Early identification of anastomotic thrombosis is important in successful free tissue transfer. Real-time, intraoperative evaluation of flap perfusion, anastomotic thrombosis, and successful revision can be performed using NIR fluorescence imaging. PMID:25571855

  2. Editorial: Next Generation Access Networks

    NASA Astrophysics Data System (ADS)

    Ruffini, Marco; Cincotti, Gabriella; Pizzinat, Anna; Vetter, Peter

    2015-12-01

    Over the past decade we have seen an increasing number of operators deploying Fibre-to-the-home (FTTH) solutions in access networks, in order to provide home users with a much needed network access upgrade, to support higher peak rates, higher sustained rates and a better and more uniform broadband coverage of the territory.

  3. The effect of metropolitan-area mortgage delinquency on health behaviors, access to health services, and self-rated health in the United States, 2003-2010.

    PubMed

    Charters, Thomas J; Harper, Sam; Strumpf, Erin C; Subramanian, S V; Arcaya, Mariana; Nandi, Arijit

    2016-07-01

    The recent housing crisis offers the opportunity to understand the effects of unique indicators of macroeconomic conditions on health. We linked data on the proportion of mortgage borrowers per US metropolitan-area who were at least 90 days delinquent on their payments with individual-level outcomes from a representative sample of 1,021,341 adults surveyed through the Behavioral Risk Factor Surveillance System (BRFSS) between 2003 and 2010. We estimated the effects of metropolitan-area mortgage delinquency on individual health behaviors, medical coverage, and health status, as well as whether effects varied by race/ethnicity. Results showed that increases in the metropolitan-area delinquency rate resulted in decreases in heavy alcohol consumption and increases in exercise and health insurance coverage. However, the delinquency rate was also associated with increases in smoking and obesity in some population groups, suggesting the housing crisis may have induced stress-related behavioral change. Overall, the effects of metropolitan-area mortgage delinquency on population health were relatively modest. PMID:27261531

  4. Comparative Efficacy of Pulse-Spray Thrombolysis and Angioplasty Versus Surgical Salvage Procedures for Treatment of Recurrent Occlusion of PTFE Dialysis Access Grafts

    SciTech Connect

    Polak, Joseph F.; Berger, Markus F.; Pagan-Marin, Heriberto; Aruny, John E.; Meyerovitz, Michael F.

    1998-07-15

    Purpose: To compare the efficacy of surgery versus pulse-spray thrombolysis and angioplasty in patients with recurrent thrombosis of polytetrafluoroethylene (PTFE) dialysis access grafts. Methods: We analyzed 96 consecutive interventions for thrombosed PTFE dialysis access grafts in 18 patients. Primary patency after thrombolysis and angioplasty (n= 25) was compared with primary patency following thrombectomy alone (n= 50) or thrombectomy followed by graft revision (n= 21) using life-table analysis. A Cox proportional hazards model that accounted for graft age and number of previous interventions was used to generate the relative risk for recurrent occlusion following therapy. Results: Life-table analysis showed that patency after thrombolysis and angioplasty was greater than that following thrombectomy alone (p= 0.02). After accounting for the age of the graft and the number of previous interventions (average six per patient), the relative risk for recurrent occlusion [3.0; 95% confidence intervals (CI): 1.5, 6.4] was greater for thrombectomy alone than for thrombolysis/angioplasty [0.6; CI = 0.3, 1.3]. The relative risks of repeat occlusion following thrombolysis/angioplasty [0.6; CI = 0.3, 1.3] and thrombectomy/surgical revision [1.0; CI = 0.5, 1.7] were similar. Conclusion: Outcome data from our retrospective study on recurrent thrombosis of PTFE dialysis access grafts suggest that thrombolysis/angioplasty is superior to thrombectomy alone, and equivalent to thrombectomy/surgical revision.

  5. Establish a perioperative check forum for peripheral intravenous access to prevent the occurrence of phlebitis.

    PubMed

    Chiu, Po-Chun; Lee, Ya-Hui; Hsu, Hung-Te; Feng, Yu-Tung; Lu, I-Cheng; Chiu, Shun-Li; Cheng, Kuang-I

    2015-04-01

    The prevalence of intravenous (IV) catheter-related infections is 0.5 per 1000 device days, and these infections cause tenderness, erythema, swelling and phlebitis. Catheter-related bloodstream infections (CRBSI) may independently increase hospital costs and length of stay; the aim of the study was to set up a standard operating procedure (SOP) for the maintenance of peripheral vein catheter patency and the prevention of IV catheter-related complications. This is a retrospective study, enrolling patients who received anesthesia between April 2010 and January 2011. The study included 1 month of pretest phase, and 3 months each of "notification" phase, "observation" phase and "end" phase, respectively. The cannulations were set up by surgical ward nurses following the SOP on establishing peripheral intravenous catheter in our hospital. The cannulation sites were then examined before surgery and postoperatively by registered nurse anesthetists using the Baxter Scale. We also tried to set up a feedback circuit to let ward nurses know about the IV patency rate. As a result, 14,682 patients were enrolled in the study. The incidence of IV therapy-related adverse events was 0.78% in the notification phase, 0.43% in the observation phase, and 0.13% in the end phase. Overall IV therapy-related events declined significantly (p < 0.01), and the presence of phlebitis was associated with age (p < 0.05). An SOP established to assess IV patency through a checklist can reduce phlebitis and improve quality. The checklist increases ward nurses' and nurse anesthetists' awareness of IV patency, and the feedback circuit substantially reduces IV event rate. PMID:25835279

  6. Pediatric Coronary Artery Revascularization Surgery: Development and Effects on Survival, Cardiac Events and Graft Patency for Children With Kawasaki Disease Coronary Involvements

    PubMed Central

    Kitamura, Soichiro

    2016-01-01

    Pediatric coronary artery bypass surgery gained wide acceptance with the introduction of internal thoracic arteries (ITAs) for bypass operations for post Kawasaki disease (KD) lesions. The technique is now established as the standard surgical choice, and its safety even in infancy, graft patency, growth potential, graft longevity and clinical efficacy have been well documented. In this article the author reviews the development of pediatric coronary bypass as the main indication for the treatment of coronary lesions due to KD. I believe that coronary revascularization surgery in pediatric population utilizing uni- or bilateral ITAs is the current gold-standard as the most reliable treatment, although percutaneous coronary intervention with or without a stent has been tried with vague long-term results in children. PMID:26848378

  7. Hemodialysis access - self care

    MedlinePlus

    Kidney failure - chronic-hemodialysis access; Renal failure - chronic-hemodialysis access; Chronic renal insufficiency - hemodialysis access; Chronic kidney failure - hemodialysis access; Chronic renal failure - hemodialysis access; dialysis - hemodialysis access

  8. Low rate of transmitted drug resistance may indicate low access to antiretroviral treatment in Maranhão State, northeast Brazil.

    PubMed

    Moura, Maria Edileuza Soares; Reis, Mônica Nogueira da Guarda; Lima, Yanna Andressa Ramos; Eulálio, Kelsen Dantas; Cardoso, Ludimila Paula Vaz; Stefani, Mariane Martins de Araújo

    2015-02-01

    The Brazilian AIDS epidemic is characterized by significant geographic contrasts: a reduction in incidence and mortality in the epicenter (southeast) and an increase in the northeast. HIV-1-transmitted drug resistance (TDR) and genetic diversity were investigated among 106 antiretroviral (ARV)-naive patients from Maranhão State, northeast. The HIV-1 protease (PR) and reverse transcriptase (RT) regions were sequenced; subtypes were assigned by REGA/phylogenetic analysis. TDR to the nucleoside/nonnucleoside reverse transcriptase inhibitor (NRTI/NNRTI) and protease inhibitor (PI) was identified by the Calibrated Population Resistance tool (Stanford). The median age was 31 years (range 18-72), with 54.7% women, 78.3% heterosexual transmission, and 17.9% men who have sex with men (MSM). Around 30% had <350 CD4(+) T cells/μl and 47.2% had plasma viral loads ≤10,000 copies/ml. The TDR rate was 3.8% (4/106; CI 95%, 1.2-8.9%) (three males, two of them MSM). Only single class mutations to NRTI (M184V; T215S) or NNRTI (K103S/N) were detected. Subtype B represented 81.1% (86/106), F1 1.9% (2/106), and C 2.8% (3/106); 14.2% were mosaics: 13 BF1 and 2 BC. Surveillance of TDR and HIV-1 genetic diversity is important to improve control strategies regionally. PMID:25411830

  9. College Access Marketing

    ERIC Educational Resources Information Center

    Tremblay, Christopher W.

    2011-01-01

    College Access Marketing (CAM) is a relatively new phenomenon that seeks to positively influence the college-going rate. This report defines CAM, describes CAM examples, and discusses how CAM seeks to counter barriers to college. It explores four main elements of CAM: information, marketing, advocacy, and social mobilization. Further, it…

  10. Accuracy of serial myocardial perfusion scintigraphy with /sup 201/Tl for prediction of graft patency early and late after coronary artery bypass surgery. A controlled prospective study

    SciTech Connect

    Pfisterer, M.; Emmenegger, H.; Schmitt, H.E.; Mueller-Brand, J.; Hasse, J.; Graedel, E.; Laver, M.B.; Burckhardt, D.; Burkart, F.

    1982-11-01

    To assess the accuracy of serial myocardial perfusion scintigraphy with /sup 201/Tl to predict graft patency early and late coronary artery bypass surgery, rest and exercise /sup 201/Tl and coronary arteriography were performed preoperatively and 2 weeks and 1 year after operation. The scintigraphic results were compared with graft patency, symptoms, left ventricular function and physical work capacity in a consecutive series of 55 patients with a total of 154 grafts. Serial /sup 201/Tl had an 80% sensitivity, 88% specificity and 86% overall accuracy in detecting or excluding graft occlusion, which was predicted by reversible ischemia as well as persistent new scar segments. Occluded grafts were correctly localized by /sup 201/Tl scintigraphy in 61%. Postoperative apical /sup 201/Tl defects were frequent (two-thirds of cases), and were the result of intraoperative transapical venting of the left ventricle. After coronary bypass graft surgery, ejection fraction at rest was unchanged. Left ventricular end-diastolic pressure and physical work capacity improved significantly. In the presence of new perfusion defects detected postoperatively, physical work capacity was reduced significantly. New /sup 201/Tl defects in addition to typical or atypical angina provided a high probability of graft occlusion, while in the absence of new /sup 201/Tl defects all grafts were patent in more than 90% of patients, all of whom had no or only atypical chest pain. We conclude that serial /sup 201/Tl imaging after coronary artery bypass surgery is an accurate noninvasive method that can be used routinely to assess graft function, to localize spatially occluded grafts and to identify patients with a high likelihood of graft occlusion who may need invasive studies.

  11. Hemodialysis access - self care

    MedlinePlus

    Kidney failure - chronic-hemodialysis access; Renal failure - chronic-hemodialysis access; Chronic renal insufficiency - hemodialysis access; Chronic kidney failure - hemodialysis access; Chronic renal failure - ...

  12. Vascular Access in Children

    SciTech Connect

    Krishnamurthy, Ganesh Keller, Marc S.

    2011-02-15

    Establishment of stable vascular access is one of the essential and most challenging procedures in a pediatric hospital. Many clinical specialties provide vascular service in a pediatric hospital. At the top of the 'expert procedural pyramid' is the pediatric interventional radiologist, who is best suited and trained to deliver this service. Growing awareness regarding the safety and high success rate of vascular access using image guidance has led to increased demand from clinicians to provide around-the-clock vascular access service by pediatric interventional radiologists. Hence, the success of a vascular access program, with the pediatric interventional radiologist as the key provider, is challenging, and a coordinated multidisciplinary team effort is essential for success. However, there are few dedicated pediatric interventional radiologists across the globe, and also only a couple of training programs exist for pediatric interventions. This article gives an overview of the technical aspects of pediatric vascular access and provides useful tips for obtaining vascular access in children safely and successfully using image guidance.

  13. Expanding Access

    ERIC Educational Resources Information Center

    Roach, Ronald

    2007-01-01

    There is no question that the United States lags behind most industrialized nations in consumer access to broadband Internet service. For many policy makers and activists, this shortfall marks the latest phase in the struggle to overcome the digital divide. To remedy this lack of broadband affordability and availability, one start-up firm--with…

  14. Access Denied

    ERIC Educational Resources Information Center

    Raths, David

    2012-01-01

    As faculty members add online and multimedia elements to their courses, colleges and universities across the country are realizing that there is a lot of work to be done to ensure that disabled students (and employees) have equal access to course material and university websites. Unfortunately, far too few schools consider the task a top priority.…

  15. Easy Access

    ERIC Educational Resources Information Center

    Gettelman, Alan

    2009-01-01

    School and university restrooms, locker and shower rooms have specific ADA accessibility requirements that serve the needs of staff, students and campus visitors who are disabled as a result of injury, illness or age. Taking good care of them is good for the reputation of a sensitive community institution, and fosters positive public relations.…

  16. Hemodialysis access procedures

    MedlinePlus

    Kidney failure - chronic-dialysis access; Renal failure - chronic-dialysis access; Chronic renal insufficiency-dialysis access; Chronic kidney failure-dialysis access; Chronic renal failure-dialysis access

  17. Authors attain comparable or slightly higher rates of citation publishing in an open access journal (CytoJournal) compared to traditional cytopathology journals - A five year (2007-2011) experience

    PubMed Central

    Frisch, Nora K.; Nathan, Romil; Ahmed, Yasin K.; Shidham, Vinod B.

    2014-01-01

    Background: The era of Open Access (OA) publication, a platform which serves to better disseminate scientific knowledge, is upon us, as more OA journals are in existence than ever before. The idea that peer-reviewed OA publication leads to higher rates of citation has been put forth and shown to be true in several publications. This is a significant benefit to authors and is in addition to another relatively less obvious but highly critical component of the OA charter, i.e. retention of the copyright by the authors in the public domain. In this study, we analyzed the citation rates of OA and traditional non-OA publications specifically for authors in the field of cytopathology. Design: We compared the citation patterns for authors who had published in both OA and traditional non-OA peer-reviewed, scientific, cytopathology journals. Citations in an OA publication (CytoJournal) were analyzed comparatively with traditional non-OA cytopathology journals (Acta Cytologica, Cancer Cytopathology, Cytopathology, and Diagnostic Cytopathology) using the data from web of science citation analysis site (based on which the impact factors (IF) are calculated). After comparing citations per publication, as well as a time adjusted citation quotient (which takes into account the time since publication), we also analyzed the statistics after excluding the data for meeting abstracts. Results: Total 28 authors published 314 publications as articles and meeting abstracts (25 authors after excluding the abstracts). The rate of citation and time adjusted citation quotient were higher for OA in the group where abstracts were included (P < 0.05 for both). The rates were also slightly higher for OA than non-OA when the meeting abstracts were excluded, but the difference was statistically insignificant (P = 0.57 and P = 0.45). Conclusion We observed that for the same author, the publications in the OA journal attained a higher rate of citation than the publications in the traditional non

  18. Hemodynamic Simulations in Dialysis Access Fistulae

    NASA Astrophysics Data System (ADS)

    McGah, Patrick; Leotta, Daniel; Beach, Kirk; Riley, James; Aliseda, Alberto

    2010-11-01

    Arteriovenous fistulae are created surgically to provide adequate access for dialysis in patients with End-Stage Renal Disease. It has long been hypothesized that the hemodynamic and mechanical forces (such as wall shear stress, wall stretch, or flow- induced wall vibrations) constitute the primary external influence on the remodeling process. Given that nearly 50% of fistulae fail after one year, understanding fistulae hemodynamics is an important step toward improving patency in the clinic. We perform numerical simulations of the flow in patient-specific models of AV fistulae reconstructed from 3D ultrasound scans with physiologically-realistic boundary conditions also obtained from Doppler ultrasound. Comparison of the flow features in different geometries and configurations e.g. end-to-side vs. side-to-side, with the in vivo longitudinal outcomes will allow us to hypothesize which flow conditions are conducive to fistulae success or failure. The flow inertia and pulsatility in the simulations (mean Re 700, max Re 2000, Wo 4) give rise to complex secondary flows and coherent vortices, further complicating the spatio- temporal variability of the wall pressure and shear stresses. Even in mature fistulae, the anastomotic regions are subjected to non-physiological shear stresses (>10.12pcPa) which may potentially lead to complications.

  19. A spun elastomeric graft for dialysis access.

    PubMed

    Drasler, W J; Wilson, G J; Stenoien, M D; Jenson, M L; George, S A; Dutcher, R G; Possis, Z C

    1993-01-01

    A new composite vascular graft was developed using electrostatic spinning technology. The graft is primarily microfibrous polydimethylsiloxane spun onto a mandrel; a small diameter polyester yarn provides additional strength while minimizing wall thickness, and a helical bead provides crush and kink resistance. Eighteen grafts were implanted in a mongrel canine arteriovenous shunt model for 12 months. The grafts were implanted in femoral artery to femoral vein loops and were cannulated using three pairs of 16 gauge dialysis needles per week. Grafts were evaluated during each puncture session, and also followed using angiography. Histologic study of explanted grafts, regional lymph nodes, and lungs was performed. The grafts provided excellent handling and puncture characteristics, with no bleeding through the graft wall at puncture sites. Cumulative patency of these punctured grafts was 88% at 6 months and 80% at 1 year. Histologic study showed external fibroconnective tissue encapsulation of the grafts, with tissue growth through the interstices of the graft consisting of a microvascular network surrounded predominantly by histiocytes, many multinucleated foreign body giant cells, with some fibroblasts and collagen formation also present. Little luminal thrombus was seen at puncture sites in the patent grafts, and there was no evidence of pulmonary thromboemboli. This new elastomeric graft shows excellent promise for dialysis access; similar grafts under development may also find application for small diameter peripheral vascular reconstruction. PMID:8324257

  20. Vascular replacement using a layered elastin-collagen vascular graft in a porcine model: one week patency versus one month occlusion

    PubMed Central

    Koens, M J W; Krasznai, A G; Hanssen, A E J; Hendriks, T; Praster, R; Daamen, W F; van der Vliet, J A; van Kuppevelt, T H

    2015-01-01

    abstract A persistent clinical demand exists for a suitable arterial prosthesis. In this study, a vascular conduit mimicking the native 3-layered artery, and constructed from the extracellular matrix proteins type I collagen and elastin, was evaluated for its performance as a blood vessel equivalent. A tubular 3-layered graft (elastin-collagen-collagen) was prepared using highly purified type I collagen fibrils and elastin fibers, resembling the 3-layered native blood vessel architecture. The vascular graft was crosslinked and heparinised (37 ± 4 μg heparin/mg graft), and evaluated as a vascular graft using a porcine bilateral iliac artery model. An intra-animal comparison with clinically-used heparinised ePTFE (Propaten®) was made. Analyses included biochemical characterization, duplex scanning, (immuno)histochemistry and scanning electron microscopy. The tubular graft was easy to handle with adequate suturability. Implantation resulted in pulsating grafts without leakage. One week after implantation, both ePTFE and the natural acellular graft had 100% patencies on duplex scanning. Grafts were partially endothelialised (Von Willebrand-positive endothelium with a laminin-positive basal membrane layer). After one month, layered thrombi were found in the natural (4/4) and ePTFE graft (1/4), resulting in occlusion which in case of the natural graft is likely due to the porosity of the inner elastin layer. In vivo application of a molecularly-defined tubular graft, based on nature's matrix proteins, for vascular surgery is feasible. PMID:26060888

  1. Vascular replacement using a layered elastin-collagen vascular graft in a porcine model: one week patency versus one month occlusion.

    PubMed

    Koens, M J W; Krasznai, A G; Hanssen, A E J; Hendriks, T; Praster, R; Daamen, W F; van der Vliet, J A; van Kuppevelt, T H

    2015-01-01

    A persistent clinical demand exists for a suitable arterial prosthesis. In this study, a vascular conduit mimicking the native 3-layered artery, and constructed from the extracellular matrix proteins type I collagen and elastin, was evaluated for its performance as a blood vessel equivalent. A tubular 3-layered graft (elastin-collagen-collagen) was prepared using highly purified type I collagen fibrils and elastin fibers, resembling the 3-layered native blood vessel architecture. The vascular graft was crosslinked and heparinised (37 ± 4 μg heparin/mg graft), and evaluated as a vascular graft using a porcine bilateral iliac artery model. An intra-animal comparison with clinically-used heparinised ePTFE (Propaten®) was made. Analyses included biochemical characterization, duplex scanning, (immuno)histochemistry and scanning electron microscopy. The tubular graft was easy to handle with adequate suturability. Implantation resulted in pulsating grafts without leakage. One week after implantation, both ePTFE and the natural acellular graft had 100% patencies on duplex scanning. Grafts were partially endothelialised (Von Willebrand-positive endothelium with a laminin-positive basal membrane layer). After one month, layered thrombi were found in the natural (4/4) and ePTFE graft (1/4), resulting in occlusion which in case of the natural graft is likely due to the porosity of the inner elastin layer. In vivo application of a molecularly-defined tubular graft, based on nature's matrix proteins, for vascular surgery is feasible. PMID:26060888

  2. Proportional Data Rate Fairness Resource Allocation for MIMO-OFDM Multiple Access Channel by Considering the Correlation Effect of Line of Sight and Non Line of Sight Channel Conditions

    NASA Astrophysics Data System (ADS)

    Maung, Sann Maw; Sasase, Iwao

    In the MIMO-OFDM multiple access channel (MIMO-OFDM-MAC) uplink scenario, the base station decides the uplink parameters for multiple users based on channel state information (CSI) from each user in the system. The performance of MIMO-OFDM-MAC systems can be significantly improved by using an adaptive transmission and resource allocation schemes which consider the correlation effect of line of sight (LOS) and non line of sight (NLOS) channel conditions for different users in the system. A lot of papers have been published on resource allocation schemes for MIMO-OFDM systems. However, most of these resource allocation schemes have been considered for MIMO-OFDMA systems, where users are separated in the frequency domain and each user uses the same uplink and downlink channels in the same channel conditions. On the other hand, in the mulituser MIMO-OFDM systems, more than one user can be assigned the same frequency and channel conditions for the MIMO-OFDM broadcast channel (downlink) and MIMO-OFDM-MAC channel (uplink) are not the same. Therefore, the same resource allocation schemes for the conventional MIMO-OFDM systems can not be applied to multiuser MIMO-OFDM systems with different uplink and downlink channel conditions. Until now, most of the resource allocation schemes have been considered only for downlink MIMO-OFDM broadcast (MIMO-OFDM-BC) channel and very few papers tackle the fairness among users. Moreover, no paper considers a scheme to realize proportional data rate fairness among users in the MIMO-OFDM-MAC condition. In this paper, we propose a proportional data rate fairness resource allocation scheme with adaptive bit loading for MIMO-ODFM-MAC systems by considering the correlation effects of LOS and NLOS channel conditions in both spatial and frequency domains. Computer simulation results show that the proposed scheme can give larger system capacity while maintaining the proportional data rate fairness requirements among users in the system under the

  3. Endovascular treatment of stent fracture and pseudoaneurysm formation in arteriovenous fistula dialysis access.

    PubMed

    Kershen, L Michael; Marichal, Daniel A

    2013-01-01

    Arteriovenous fistulae (AVF) and grafts (AVG) for hemodialysis access generally provide good long-term solutions for the patient with end-stage renal disease. However, complications of both AVGs and AVFs are common and require a multimodality approach to maintain their patency and continued use. Commonly encountered problems include stenosis, thrombosis, aneurysm or pseudoaneurysm formation, rupture, and infection. Each needs to be addressed on a case-by-case basis. Outflow stenosis, often occurring within the cephalic arch in patients with a brachiocephalic fistula, may occur alone or be discovered in conjunction with other access problems. Pseudoaneurysm of the venous end generally arises from traumatic weakening of the vessel wall, often from repetitive venipuncture. More rare is the fracture of a previously placed stent. We present a case of stent fracture complicated by pseudoaneurysm formation with concomitant stenosis of the cephalic arch treated successfully with single-procedure placement of endovascular stent grafts. PMID:23382614

  4. Handbook of noise ratings

    NASA Technical Reports Server (NTRS)

    Pearsons, K. S.; Bennett, R. L.

    1974-01-01

    The handbook was compiled to provide information in a concise form, describing the multitude of noise rating schemes. It is hoped that by describing the noise rating methods in a single volume the user will have better access to the definitions, application and calculation procedures of the current noise rating methods.

  5. [Influence of the permeability of the artery responsible for the infarction on the variability of heart rate and late potentials. Its importance in the risk stratification after myocardial infarction].

    PubMed

    Dorado, M; González-Hermosillo, J A; García Arenal, F; Colín, L; Kershenovich, S; Romero, L; Iturralde, P

    1993-02-01

    The use of the heart rate variability for the study of the Autonomic nervous system has been well established. We analyzed late potentials and heart rate variability in 29 control patients and in 102 consecutive patients with a first myocardial infarction. The data obtained were analyzed with both, the medical treatment (thrombolysis and beta-blockers) and the patency of the infarct related vessel. Patients with an infarct had diminished vagal tone as compared with the control group. Those patients with occluded related arteries showed higher incidence of late potentials; interestingly patients with late potentials also had diminished vagal tone. Without looking at the patency of the infarct related artery, thrombolitic and betablocker therapy did not have any effect on vagal tone. All the variables were correlated with the patency of the infarct related artery. Those patients with patent arteries had a preservation of the vagal tone; this was independent of the treatment received and the presence of late potentials. We concluded that the patency of the infarct related artery determines the absence of late potentials and preservation of the vagal tone. This might be one of the mechanisms of how thrombolitic therapy decreases the incidence of cardiac death. PMID:8451487

  6. United States Access Board

    MedlinePlus

    ... disabilities through leadership in accessible design and the development of accessibility guidelines and standards for the built environment, transportation, communication, medical diagnostic equipment, and information technology. ...

  7. 47 CFR 51.907 - Transition of price cap carrier access charges.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... “trunking basket” as described in 47 CFR 61.42(d)(2) and (3) to the extent that such rate elements are not... Office Access Rate if its intrastate terminating end office access rates would be at rate parity with its... end office access rates would be at rate parity with its interstate terminating end office...

  8. A Theory of Access

    ERIC Educational Resources Information Center

    Ribot, Jesse C.; Peluso, Nancy Lee

    2003-01-01

    The term "access" is frequently used by property and natural resource analysts without adequate definition. In this paper we develop a concept of access and examine a broad set of factors that differentiate access from property. We define access as "the "ability" to derive benefits from things," broadening from property's classical definition as…

  9. World Wide Access: Accessible Web Design.

    ERIC Educational Resources Information Center

    Washington Univ., Seattle.

    This brief paper considers the application of "universal design" principles to Web page design in order to increase accessibility for people with disabilities. Suggestions are based on the World Wide Web Consortium's accessibility initiative, which has proposed guidelines for all Web authors and federal government standards. Seven guidelines for…

  10. Aneurysms of Hemodialysis Access Grafts: Treatment with Covered Stents: A Report of Three Cases

    SciTech Connect

    Hausegger, Klaus A.; Tiessenhausen, Kurt; Klimpfinger, Martin; Raith, Johann; Hauser, Hubert; Tauss, Josef

    1998-07-15

    Three patients with dialysis access graft shunts, having a symptomatic pseudoaneurysm and a hemodynamically significant stenosis at the anastomosis between the graft shunt and the subclavian vein, were treated with percutaneous transluminal angioplasty and insertion of a Wallstent. Pseudoaneurysms were excluded by percutaneous insertion of a Cragg Endo-Pro stent-graft with a diameter of 6 mm and a length of 6-10 cm. All three aneurysms were excluded successfully. In two patients, the stent-graft was punctured repeatedly during follow-up and the aneurysms recurred after 7 and 8 months, respectively. The patency of the dialysis shunt after stent-graft insertion was 8 (n= 1) and 9 months (n= 2). Due to the recurrence of the aneurysm (n= 2) or recurrent thrombosis (n= 1) the use of these shunts was discontinued.

  11. Controlling Access to Suicide Means

    PubMed Central

    Sarchiapone, Marco; Mandelli, Laura; Iosue, Miriam; Andrisano, Costanza; Roy, Alec

    2011-01-01

    Background: Restricting access to common means of suicide, such as firearms, toxic gas, pesticides and other, has been shown to be effective in reducing rates of death in suicide. In the present review we aimed to summarize the empirical and clinical literature on controlling the access to means of suicide. Methods: This review made use of both MEDLINE, ISI Web of Science and the Cochrane library databases, identifying all English articles with the keywords “suicide means”, “suicide method”, “suicide prediction” or “suicide prevention” and other relevant keywords. Results: A number of factors may influence an individual’s decision regarding method in a suicide act, but there is substantial support that easy access influences the choice of method. In many countries, restrictions of access to common means of suicide has lead to lower overall suicide rates, particularly regarding suicide by firearms in USA, detoxification of domestic and motor vehicle gas in England and other countries, toxic pesticides in rural areas, barriers at jumping sites and hanging, by introducing “safe rooms” in prisons and hospitals. Moreover, decline in prescription of barbiturates and tricyclic antidepressants (TCAs), as well as limitation of drugs pack size for paracetamol and salicylate has reduced suicides by overdose, while increased prescription of SSRIs seems to have lowered suicidal rates. Conclusions: Restriction to means of suicide may be particularly effective in contexts where the method is popular, highly lethal, widely available, and/or not easily substituted by other similar methods. However, since there is some risk of means substitution, restriction of access should be implemented in conjunction with other suicide prevention strategies. PMID:22408588

  12. Hemodialysis access procedures

    MedlinePlus

    National Kidney and Urologic Diseases Information Clearinghouse. Vascular Access for Hemodialysis . Updated July 23, 2014. Available at: kidney.niddk.nih.gov/kudiseases/pubs/vascularaccess/index.aspx. Accessed: February 9, 2015. ...

  13. [Accessible Rural Housing.

    ERIC Educational Resources Information Center

    Baker, Nick, Ed.

    1995-01-01

    This issue of the quarterly newsletter "Rural Exchange" provides information and resources on accessible rural housing for the disabled. "Accessible Manufactured Housing Could Increase Rural Home Supply" (Nick Baker) suggests that incorporation of access features such as lever door handles and no-step entries into manufactured housing could help…

  14. Open Access Alternatives

    ERIC Educational Resources Information Center

    Tenopir, Carol

    2004-01-01

    Open access publishing is a hot topic today. But open access publishing can have many different definitions, and pros and cons vary with the definitions. Open access publishing is especially attractive to companies and small colleges or universities that are likely to have many more readers than authors. A downside is that a membership fee sounds…

  15. Demystifying Remote Access

    ERIC Educational Resources Information Center

    Howe, Grant

    2009-01-01

    With money tight, more and more districts are considering remote access as a way to reduce expenses and budget information technology costs more effectively. Remote access allows staff members to work with a hosted software application from any school campus without being tied to a specific physical location. Each school can access critical…

  16. Open Access and beyond.

    PubMed

    Mathur, Shawn; Schmidt, Christian; Das, Chhaya; Tucker, Philip W

    2006-01-01

    Uncensored exchange of scientific results hastens progress. Open Access does not stop at the removal of price and permission barriers; still, censorship and reading disabilities, to name a few, hamper access to information. Here, we invite the scientific community and the public to discuss new methods to distribute, store and manage literature in order to achieve unfettered access to literature. PMID:16956402

  17. Reflective Database Access Control

    ERIC Educational Resources Information Center

    Olson, Lars E.

    2009-01-01

    "Reflective Database Access Control" (RDBAC) is a model in which a database privilege is expressed as a database query itself, rather than as a static privilege contained in an access control list. RDBAC aids the management of database access controls by improving the expressiveness of policies. However, such policies introduce new interactions…

  18. National Utility Rate Database: Preprint

    SciTech Connect

    Ong, S.; McKeel, R.

    2012-08-01

    When modeling solar energy technologies and other distributed energy systems, using high-quality expansive electricity rates is essential. The National Renewable Energy Laboratory (NREL) developed a utility rate platform for entering, storing, updating, and accessing a large collection of utility rates from around the United States. This utility rate platform lives on the Open Energy Information (OpenEI) website, OpenEI.org, allowing the data to be programmatically accessed from a web browser, using an application programming interface (API). The semantic-based utility rate platform currently has record of 1,885 utility rates and covers over 85% of the electricity consumption in the United States.

  19. 47 CFR 76.978 - Leased access annual reporting requirement.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... rate and actual rates. (5) The programmers using each commercial leased access channel and whether each programmer is using the channel on a full-time or part-time basis. (6) The number of requests received for... different rates, terms, or conditions on commercial leased access programmers (such as with respect...

  20. 47 CFR 76.978 - Leased access annual reporting requirement.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... rate and actual rates. (5) The programmers using each commercial leased access channel and whether each programmer is using the channel on a full-time or part-time basis. (6) The number of requests received for... different rates, terms, or conditions on commercial leased access programmers (such as with respect...

  1. 47 CFR 76.978 - Leased access annual reporting requirement.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... rate and actual rates. (5) The programmers using each commercial leased access channel and whether each programmer is using the channel on a full-time or part-time basis. (6) The number of requests received for... different rates, terms, or conditions on commercial leased access programmers (such as with respect...

  2. Fast Access Data Acquisition System

    SciTech Connect

    Dr. Vladimir Katsman

    1998-03-17

    Our goal in this program is to develop Fast Access Data Acquisition System (FADAS) by combining the flexibility of Multilink's GaAs and InP electronics and electro-optics with an extremely high data rate for the efficient handling and transfer of collider experimental data. This novel solution is based on Multilink's and Los Alamos National Laboratory's (LANL) unique components and technologies for extremely fast data transfer, storage, and processing.

  3. Is random access memory random?

    NASA Technical Reports Server (NTRS)

    Denning, P. J.

    1986-01-01

    Most software is contructed on the assumption that the programs and data are stored in random access memory (RAM). Physical limitations on the relative speeds of processor and memory elements lead to a variety of memory organizations that match processor addressing rate with memory service rate. These include interleaved and cached memory. A very high fraction of a processor's address requests can be satified from the cache without reference to the main memory. The cache requests information from main memory in blocks that can be transferred at the full memory speed. Programmers who organize algorithms for locality can realize the highest performance from these computers.

  4. Patency of Litomosoides sigmodontis infection depends on Toll-like receptor 4 whereas Toll-like receptor 2 signalling influences filarial-specific CD4(+) T-cell responses.

    PubMed

    Rodrigo, Maria B; Schulz, Sandy; Krupp, Vanessa; Ritter, Manuel; Wiszniewsky, Katharina; Arndts, Kathrin; Tamadaho, Ruth S E; Endl, Elmar; Hoerauf, Achim; Layland, Laura E

    2016-04-01

    BALB/c mice develop a patent state [release of microfilariae (Mf), the transmission life-stage, into the periphery] when exposed to the rodent filariae Litomosoides sigmodontis. Interestingly, only a portion of the infected mice become patent, which reflects the situation in human individuals infected with Wuchereria bancrofti. Since those individuals had differing filarial-specific profiles, this study compared differences in immune responses between Mf(+) and Mf(-) infected BALB/c mice. We demonstrate that cultures of total spleen or mediastinal lymph node cells from Mf(+) mice produce significantly more interleukin-5 (IL-5) to filarial antigens but equal levels of IL-10 when compared with Mf(-) mice. However, isolated CD4(+) T cells from Mf(+) mice produced significantly higher amounts of all measured cytokines, including IL-10, when compared with CD4(+) T-cell responses from Mf(-) mice. Since adaptive immune responses are influenced by triggering the innate immune system we further studied the immune profiles and parasitology in infected Toll-like receptor-2-deficient (TLR2(-/-)) and TLR4(-/-) BALB/c mice. Ninety-three per cent of L. sigmodontis-exposed TLR4(-/-) BALB/c mice became patent (Mf(+)) although worm numbers remained comparable to those in Mf(+) wild-type controls. Lack of TLR2 had no influence on patency outcome or worm burden but infected Mf(+) mice had significantly lower numbers of Foxp3(+) regulatory T cells and dampened peripheral immune responses. Interestingly, in vitro culturing of CD4(+) T cells from infected wild-type mice with granulocyte-macrophage colony-stimulating factor-derived TLR2(-/-) dendritic cells resulted in an overall diminished cytokine profile to filarial antigens. Hence, triggering TLR4 or TLR2 during chronic filarial infection has a significant impact on patency and efficient CD4(+) T-cell responses, respectively. PMID:26714796

  5. Access to Scientific Publications: The Scientist's Perspective

    PubMed Central

    Voronin, Yegor; Myrzahmetov, Askar; Bernstein, Alan

    2011-01-01

    Background Scientific publishing is undergoing significant changes due to the growth of online publications, increases in the number of open access journals, and policies of funders and universities requiring authors to ensure that their publications become publicly accessible. Most studies of the impact of these changes have focused on the growth of articles available through open access or the number of open-access journals. Here, we investigated access to publications at a number of institutes and universities around the world, focusing on publications in HIV vaccine research – an area of biomedical research with special importance to the developing world. Methods and Findings We selected research papers in HIV vaccine research field, creating: 1) a first set of 50 most recently published papers with keywords “HIV vaccine” and 2) a second set of 200 articles randomly selected from those cited in the first set. Access to the majority (80%) of the recently published articles required subscription, while cited literature was much more accessible (67% freely available online). Subscriptions at a number of institutions around the world were assessed for providing access to subscription-only articles from the two sets. The access levels varied widely, ranging among institutions from 20% to 90%. Through the WHO-supported HINARI program, institutes in low-income countries had access comparable to that of institutes in the North. Finally, we examined the response rates for reprint requests sent to corresponding authors, a method commonly used before internet access became widespread. Contacting corresponding authors with requests for electronic copies of articles by email resulted in a 55-60% success rate, although in some cases it took up to 1.5 months to get a response. Conclusions While research articles are increasingly available on the internet in open access format, institutional subscriptions continue to play an important role. However, subscriptions do not

  6. Educational Quality, Access, and Tuition Policy at State Universities.

    ERIC Educational Resources Information Center

    Seneca, Joseph J.; Taussig, Michael K.

    1987-01-01

    A quantitative study of the relationship between educational quality, access, and tuition rates at state universities suggests that these institutions face a trade-off between the goals of improving educational program quality and providing greater access, but that increases in student financial aid can improve access. (MSE)

  7. Demystifying Open Access

    SciTech Connect

    Mele, Salvatore

    2007-05-14

    The tenets of Open Access are to grant anyone, anywhere and anytime free access to the results of scientific research. HEP spearheaded the Open Access dissemination of scientific results with the mass mailing of preprints in the pre-WWW era and with the launch of the arXiv preprint system at the dawn of the '90s. The HEP community is now ready for a further push to Open Access while retaining all the advantages of the peer-review system and, at the same time, bring the spiralling cost of journal subscriptions under control. I will present a possible plan for the conversion to Open Access of HEP peer-reviewed journals, through a consortium of HEP funding agencies, laboratories and libraries: SCOAP3 (Sponsoring Consortium for Open Access Publishing in Particle Physics). SCOAP3 will engage with scientific publishers towards building a sustainable model for Open Access publishing, which is as transparent as possible for HEP authors. The current system in which journals income comes from subscription fees is replaced with a scheme where SCOAP3 compensates publishers for the costs incurred to organise the peer-review service and give Open Access to the final version of articles. SCOAP3 will be funded by all countries active in HEP under a 'fair share' scenario, according to their production of HEP articles. In this talk I will present a short overview of the history of Open Access in HEP, the details of the SCOAP3 model and the outlook for its implementation.

  8. Demystifying Open Access

    SciTech Connect

    Mele, Salvatore

    2007-05-14

    The tenets of Open Access are to grant anyone, anywhere and anytime free access to the results of scientific research. HEP spearheaded the Open Access dissemination of scientific results with the mass mailing of preprints in the pre-WWW era and with the launch of the arXiv preprint system at the dawn of the '90s. The HEP community is now ready for a further push to Open Access while retaining all the advantages of the peer-review system and, at the same time, bring the spiralling cost of journal subscriptions under control. I will present a possible plan for the conversion to Open Access of HEP peer-reviewed journals, through a consortium of HEP funding agencies, laboratories and libraries: SCOAP3 (Sponsoring Consortium for Open Access Publishing in Particle Physics). SCOAP3 will engage with scientific publishers towards building a sustainable model for Open Access publishing, which is as transparent as possible for HEP authors. The current system in which journals income comes from subscription fees is replaced with a scheme where SCOAP3 compensates publishers for the costs incurred to organise the peer-review service and give Open Access to the final version of articles. SCOAP3 will be funded by all countries active in HEP under a "fair share" scenario, according to their production of HEP articles. In this talk I will present a short overview of the history of Open Access in HEP, the details of the SCOAP3 model and the outlook for its implementation.

  9. Access Interface Strategies

    PubMed Central

    Fager, Susan; Beukelman, David R.; Fried-Oken, Melanie; Jakobs, Tom; Baker, John

    2013-01-01

    Individuals who rely on augmentative and alternative communication (AAC) devices to support their communication often have physical movement challenges that require alternative methods of access. Technology that supports access, particularly for those with the most severe movement deficits, have expanded substantially over the years. The purposes of this article are to review the state of the science of access technologies that interface with augmentative and alternative communication devices and to propose a future research and development agenda that will enhance access options for people with limited movement capability due to developmental and acquired conditions. PMID:22590797

  10. Surveillance of hemodialysis vascular access with ultrasound vector flow imaging

    NASA Astrophysics Data System (ADS)

    Brandt, Andreas H.; Olesen, Jacob B.; Hansen, Kristoffer L.; Rix, Marianne; Jensen, Jørgen A.; Nielsen, Michael B.

    2015-03-01

    The aim of this study was prospectively to monitor the volume flow in patients with arteriovenous fistula (AVF) with the angle independent ultrasound technique Vector Flow Imaging (VFI). Volume flow values were compared with Ultrasound dilution technique (UDT). Hemodialysis patients need a well-functioning vascular access with as few complications as possible and preferred vascular access is an AVF. Dysfunction due to stenosis is a common complication, and regular monitoring of volume flow is recommended to preserve AVF patency. UDT is considered the gold standard for volume flow surveillance, but VFI has proven to be more precise, when performing single repeated instantaneous measurements. Three patients with AVF were monitored with UDT and VFI monthly for five months. A commercial ultrasound scanner with a 9 MHz linear array transducer with integrated VFI was used to obtain data. UDT values were obtained with Transonic HD03 Flow-QC Hemodialysis Monitor. Three independent measurements at each scan session were obtained with UDT and VFI each month. Average deviation of volume flow between UDT and VFI was 25.7 % (Cl: 16.7% to 34.7%) (p= 0.73). The standard deviation for all patients, calculated from the mean variance of each individual scan sessions, was 199.8 ml/min for UDT and 47.6 ml/min for VFI (p = 0.002). VFI volume flow values were not significantly different from the corresponding estimates obtained using UDT, and VFI measurements were more precise than UDT. The study indicates that VFI can be used for surveillance of volume flow.

  11. Optical Access Networks

    NASA Astrophysics Data System (ADS)

    Zheng, Jun; Ansari, Nirwan

    2005-05-01

    Call for Papers: Optical Access Networks With the wide deployment of fiber-optic technology over the past two decades, we have witnessed a tremendous growth of bandwidth capacity in the backbone networks of today's telecommunications infrastructure. However, access networks, which cover the "last-mile" areas and serve numerous residential and small business users, have not been scaled up commensurately. The local subscriber lines for telephone and cable television are still using twisted pairs and coaxial cables. Most residential connections to the Internet are still through dial-up modems operating at a low speed on twisted pairs. As the demand for access bandwidth increases with emerging high-bandwidth applications, such as distance learning, high-definition television (HDTV), and video on demand (VoD), the last-mile access networks have become a bandwidth bottleneck in today's telecommunications infrastructure. To ease this bottleneck, it is imperative to provide sufficient bandwidth capacity in the access networks to open the bottleneck and thus present more opportunities for the provisioning of multiservices. Optical access solutions promise huge bandwidth to service providers and low-cost high-bandwidth services to end users and are therefore widely considered the technology of choice for next-generation access networks. To realize the vision of optical access networks, however, many key issues still need to be addressed, such as network architectures, signaling protocols, and implementation standards. The major challenges lie in the fact that an optical solution must be not only robust, scalable, and flexible, but also implemented at a low cost comparable to that of existing access solutions in order to increase the economic viability of many potential high-bandwidth applications. In recent years, optical access networks have been receiving tremendous attention from both academia and industry. A large number of research activities have been carried out or

  12. Optical Access Networks

    NASA Astrophysics Data System (ADS)

    Zheng, Jun; Ansari, Nirwan; Jersey Inst Ansari, New; Jersey Inst, New

    2005-04-01

    Call for Papers: Optical Access Networks With the wide deployment of fiber-optic technology over the past two decades, we have witnessed a tremendous growth of bandwidth capacity in the backbone networks of today's telecommunications infrastructure. However, access networks, which cover the "last-mile" areas and serve numerous residential and small business users, have not been scaled up commensurately. The local subscriber lines for telephone and cable television are still using twisted pairs and coaxial cables. Most residential connections to the Internet are still through dial-up modems operating at a low speed on twisted pairs. As the demand for access bandwidth increases with emerging high-bandwidth applications, such as distance learning, high-definition television (HDTV), and video on demand (VoD), the last-mile access networks have become a bandwidth bottleneck in today's telecommunications infrastructure. To ease this bottleneck, it is imperative to provide sufficient bandwidth capacity in the access networks to open the bottleneck and thus present more opportunities for the provisioning of multiservices. Optical access solutions promise huge bandwidth to service providers and low-cost high-bandwidth services to end users and are therefore widely considered the technology of choice for next-generation access networks. To realize the vision of optical access networks, however, many key issues still need to be addressed, such as network architectures, signaling protocols, and implementation standards. The major challenges lie in the fact that an optical solution must be not only robust, scalable, and flexible, but also implemented at a low cost comparable to that of existing access solutions in order to increase the economic viability of many potential high-bandwidth applications. In recent years, optical access networks have been receiving tremendous attention from both academia and industry. A large number of research activities have been carried out or

  13. Optical Access Networks

    NASA Astrophysics Data System (ADS)

    Zheng, Jun; Ansari, Nirwan

    2005-06-01

    Call for Papers: Optical Access Networks With the wide deployment of fiber-optic technology over the past two decades, we have witnessed a tremendous growth of bandwidth capacity in the backbone networks of today's telecommunications infrastructure. However, access networks, which cover the "last-mile" areas and serve numerous residential and small business users, have not been scaled up commensurately. The local subscriber lines for telephone and cable television are still using twisted pairs and coaxial cables. Most residential connections to the Internet are still through dial-up modems operating at a low speed on twisted pairs. As the demand for access bandwidth increases with emerging high-bandwidth applications, such as distance learning, high-definition television (HDTV), and video on demand (VoD), the last-mile access networks have become a bandwidth bottleneck in today's telecommunications infrastructure. To ease this bottleneck, it is imperative to provide sufficient bandwidth capacity in the access networks to open the bottleneck and thus present more opportunities for the provisioning of multiservices. Optical access solutions promise huge bandwidth to service providers and low-cost high-bandwidth services to end users and are therefore widely considered the technology of choice for next-generation access networks. To realize the vision of optical access networks, however, many key issues still need to be addressed, such as network architectures, signaling protocols, and implementation standards. The major challenges lie in the fact that an optical solution must be not only robust, scalable, and flexible, but also implemented at a low cost comparable to that of existing access solutions in order to increase the economic viability of many potential high-bandwidth applications. In recent years, optical access networks have been receiving tremendous attention from both academia and industry. A large number of research activities have been carried out or

  14. [Permanent vascular access for haemodialysis].

    PubMed

    Manafov, E N; Batrashov, V A; Sergeev, O G; Yudaev, S S

    2015-01-01

    The presence of a permanent vascular access (PVA) is the pledge of successful treatment of patients being on chronic haemodialysis (CD). Creation and maintenance of a functioning PVA is the priority task of vascular and endovascular surgeons, nephrologists and specialists of haemodialysis departments. According to the KDOQI guidelines, the most preferable type of PVA is a native arteriovenous fistula (AVF). As an alternative it is possible to use a synthetic prosthesis for creating an arteriovenous shunt (AVS) or implantation of a central venous catheter (CVC). Various complications of vascular accesses leading to their loss create the necessity of forming just another PVA, thus negatively influencing the life span and quality of life of this cohort of patients. Improving surgical technique and approaches to treatment, as well as carrying out dynamic monitoring of the condition of the created PVA make it possible to considerably decrease the incidence rate of such complications and to improve the quality of medical care rendered. PMID:26451410

  15. Access routes for nutritional therapy.

    PubMed

    Waitzberg, D L; Plopper, C; Terra, R M

    2000-12-01

    Enteral nutrition (EN) and total parenteral nutrition (TPN) may provide life-sustaining therapy for surgical patients. The duration of nutritional therapy (enteral or parenteral) implies distinct access routes. We review the main aspects related to access routes for nutrient delivery. The enteral route, whenever feasible, is preferred. For EN lasting less than 6 weeks, nasoenteric tubes are the route of choice. Conversely, enterostomy tubes should be used for longer-term enteral feeding and can be placed surgically or with fluoroscopic and endoscopic assistance. The first choice for patients who will not be submitted to laparotomy is percutaneous endoscopic gastrostomy. Postpyloric access, although not consensual, must be considered when there is a high risk of aspiration. For intravenous delivery of nutrients lasting less than 10 days, the peripheral route can be used. However, because of frequent infusion phlebitis, its role is still in discussion. Central venous catheters (CVCs) for TPN delivery may be (1) nonimplantable, percutaneous, nontunneled-used for a few days to 3 to 4 weeks; (2) partially implantable, percutaneous, tunneled-used for longer periods and permanent access; or (3) totally implantable subcutaneous ports-also used for long-term or permanent access. The subclavian vein is usually the insertion site of choice for central venous catheters. Implantable ports are associated with lower rates of septic complications than percutaneous CVCs. The catheter with the least number of necessary lumens should be applied. Central venous nutrient delivery can also be accomplished through peripherally inserted central catheters, which avoid insertion-related risks. PMID:11193710

  16. The first/last access protocol

    NASA Astrophysics Data System (ADS)

    Karol, M. J.; Schwartz, S. C.

    When a random access protocol is used to share a communications channel, conflicts arising from simultaneous transmissions must be resolved. Listening to feedback on a broadcast channel, and using knowledge of round trip propagation delays, the First/Last Access Protocol (FLAP) reserves time for retransmissions of the 'first' and 'last' packets involved in a channel collision. Time slots of duration greater than a packet transmission time exploit the advantages of both slotted access protocols. The maximum achievable system throughput is 0.673 as the input rate increases. Extensions of FLAP yield system throughputs greater than 0.80.

  17. Accessing the Microform Publication.

    ERIC Educational Resources Information Center

    Schindler, Stan

    1985-01-01

    Characterizes types of indexing programs used by Research Publications, Inc. and describes provision of access to four major projects: "The Official Washington Post Index" (provides access to newspaper and microfilm edition); "The Eighteenth Century"; "The Declassified Documents Reference System" (ongoing fiche project abstracted and indexed…

  18. ACCESS Pointing Control System

    NASA Technical Reports Server (NTRS)

    Brugarolas, Paul; Alexander, James; Trauger, John; Moody, Dwight; Egerman, Robert; Vallone, Phillip; Elias, Jason; Hejal, Reem; Camelo, Vanessa; Bronowicki, Allen; O'Connor, David; Partrick, Richard; Orzechowski, Pawel; Spitter, Connie; Lillie, Chuck

    2010-01-01

    ACCESS (Actively-Corrected Coronograph for Exoplanet System Studies) was one of four medium-class exoplanet concepts selected for the NASA Astrophysics Strategic Mission Concept Study (ASMCS) program in 2008/2009. The ACCESS study evaluated four major coronograph concepts under a common space observatory. This paper describes the high precision pointing control system (PCS) baselined for this observatory.

  19. Access to Higher Education

    ERIC Educational Resources Information Center

    Briscoe, Felecia; De Oliver, Miguel

    2006-01-01

    This case study researches the degree to which the location and services offered by a multicampus university, geographically situated consistent with the commercial principles of a large mass-market enterprise, facilitate access for educationally underserved groups. First, the necessity of democratizing educational access to an underprivileged…

  20. Intellectual Access to Images.

    ERIC Educational Resources Information Center

    Chen, Hsin-Liang; Rasmussen, Edie M.

    1999-01-01

    The increased availability of digital images is accompanied by a need for solutions to the problems inherent in indexing them for retrieval. Problems in image description and access are discussed, with a perspective on traditional and new solutions. Recent developments in intellectual access to images are surveyed and contrasted with…

  1. The Universal Access System.

    ERIC Educational Resources Information Center

    Scott, Neil G.

    This final report discusses the outcomes of a project that created a Universal Access System (UAS), a system that gives students with disabilities access to the same computers as their classmates. The project developed a new approach in which the needs of the individual with disabilities are handled separately from the computers and other devices…

  2. MedlinePlus: Accessibility

    MedlinePlus

    ... Tools Español You Are Here: Home → MedlinePlus Accessibility URL of this page: https://medlineplus.gov/accessibility.html ... or (301) 594-5983 and provide the address (URL) of the page on which you need assistance, ...

  3. Access and Technology

    ERIC Educational Resources Information Center

    Watson, Lemuel W.

    2004-01-01

    Community colleges are well positioned to provide underserved student populations with access to computer technology. This chapter explores the issues of access and technology from multiple perspectives in the community college, and explains how community colleges can develop a foundation for their technology plan.

  4. Improving School Access Control

    ERIC Educational Resources Information Center

    National Clearinghouse for Educational Facilities, 2008

    2008-01-01

    Few things are more important for school safety and security than controlling access to buildings and grounds. It is relatively easy to incorporate effective access control measures in new school designs but more difficult in existing schools, where most building and site features cannot be readily altered or reconfigured. The National…

  5. Optical Access Networks

    NASA Astrophysics Data System (ADS)

    Zheng, Jun; Ansari, Nirwan

    2005-03-01

    Call for Papers: Optical Access Networks With the wide deployment of fiber-optic technology over the past two decades, we have witnessed a tremendous growth of bandwidth capacity in the backbone networks of today's telecommunications infrastructure. However, access networks, which cover the "last-mile" areas and serve numerous residential and small business users, have not been scaled up commensurately. The local subscriber lines for telephone and cable television are still using twisted pairs and coaxial cables. Most residential connections to the Internet are still through dial-up modems operating at a low speed on twisted pairs. As the demand for access bandwidth increases with emerging high-bandwidth applications, such as distance learning, high-definition television (HDTV), and video on demand (VoD), the last-mile access networks have become a bandwidth bottleneck in today's telecommunications infrastructure. To ease this bottleneck, it is imperative to provide sufficient bandwidth capacity in the access networks to open the bottleneck and thus present more opportunities for the provisioning of multiservices. Optical access solutions promise huge bandwidth to service providers and low-cost high-bandwidth services to end users and are therefore widely considered the technology of choice for next-generation access networks. To realize the vision of optical access networks, however, many key issues still need to be addressed, such as network architectures, signaling protocols, and implementation standards. The major challenges lie in the fact that an optical solution must be not only robust, scalable, and flexible, but also implemented at a low cost comparable to that of existing access solutions in order to increase the economic viability of many potential high-bandwidth applications. In recent years, optical access networks have been receiving tremendous attention from both academia and industry. A large number of research activities have been carried out or

  6. 47 CFR 61.26 - Tariffing of competitive interstate switched exchange access services.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... equivalent of the ILEC interstate exchange access services typically associated with following rate elements... switched exchange access services shall mean the composite, per-minute rate for these services, including... switched exchange access services that prices those services above the higher of: (1) The rate charged...

  7. Multiple Access Trade Study

    NASA Technical Reports Server (NTRS)

    Motamedi, Masoud

    1990-01-01

    The Personal Access Satellite System (PASS) strawman design uses a hybrid Time Division Multiple Access (TDMA)/Frequency Division Multiple Access (FDMA) implementation. TDMA is used for the forward direction (from Suppliers to Users), and FDMA for the return direction (from Users to Suppliers). An alternative architecture is proposed that will require minimal real time coordination and yet provide a fast access method by using random access Code Division Multiple Access (CDMA). The CDMA system issues are addressed such as connecting suppliers and users, both of whom may be located anywhere in the CONUS, when the user terminals are constrained in size and weight; and providing efficient traffic routing under highly variable traffic requirements. It is assumed that bandwidth efficiency is not of paramount importance. CDMA or Spread Spectrum Multiple Access (SSMA) communication is a method in which a group of carriers operate at the same nominal center frequency but are separable from each other by the low cross correlation of the spreading codes used. Interference and multipath rejection capability, ease of selective addressing and message screening, low density power spectra for signal hiding and security, and high resolution ranging are among the benefits of spread spectrum communications.

  8. Peripheral Stent Placement in Hemodialysis Grafts

    SciTech Connect

    Kariya, Shuji Tanigawa, Noboru; Kojima, Hiroyuki; Komemushi, Atsushi; Shomura, Yuzo; Shiraishi, Tomokuni; Kawanaka, Toshiaki; Sawada, Satoshi

    2009-09-15

    The purpose of the present study was to evaluate the clinical outcome of peripheral stent placement after failed balloon angioplasty in patients with grafts who are on hemodialysis. We examined 30 Wallstents that were placed in 26 patients because balloon angioplasty failed or early restenosis (<3 months) occurred within 3 months. We retrospectively reviewed 267 consecutive balloon angioplasties performed in 71 patients with graft access between August 2000 and March 2007. Stent placements accounted for 30 (11.2%) of the 267 balloon angioplasties. The clinical success rate of stent placement was 93.3% (28 of 30 stent placements). The 3-, 6-, and 12-month primary patency rates were 73.3%, 39.3%, and 17.7%, respectively. The 1-, 2-, and 3-year secondary patency rates were 90.2%, 83.8%, and 83.8%, respectively. Primary patency was significantly prolonged by stent placement after early restenosis compared with previous balloon angioplasty alone (P = 0.0059). Primary patency after stent placement was significantly lower than after successful balloon angioplasty without indications for stent placement (P = 0.0279). Secondary patency rates did not significantly differ between stent placement and balloon angioplasty alone. The mean number of reinterventions required to maintain secondary patency after stent placement was significantly larger than that after balloon angioplasty alone (Mann-Whitney U test, P = 0.0419). We concluded that peripheral stent placement for graft access is effective for salvaging vascular access after failed balloon angioplasty and for prolonging patency in early restenosis after balloon angioplasty. However, reinterventions are required to maintain secondary patency after stent placement. Furthermore, peripheral stent placement for graft access cannot achieve the same primary patency as balloon angioplasty alone.

  9. Optical Access Networks

    NASA Astrophysics Data System (ADS)

    Zheng, Jun; Ansari, Nirwan

    2005-01-01

    Call for Papers: Optical Access Networks

    Guest Editors Jun Zheng, University of Ottawa Nirwan Ansari, New Jersey Institute of Technology

    Submission Deadline: 1 June 2005

    Background

    With the wide deployment of fiber-optic technology over the past two decades, we have witnessed a tremendous growth of bandwidth capacity in the backbone networks of today's telecommunications infrastructure. However, access networks, which cover the "last-mile" areas and serve numerous residential and small business users, have not been scaled up commensurately. The local subscriber lines for telephone and cable television are still using twisted pairs and coaxial cables. Most residential connections to the Internet are still through dial-up modems operating at a low speed on twisted pairs. As the demand for access bandwidth increases with emerging high-bandwidth applications, such as distance learning, high-definition television (HDTV), and video on demand (VoD), the last-mile access networks have become a bandwidth bottleneck in today's telecommunications infrastructure. To ease this bottleneck, it is imperative to provide sufficient bandwidth capacity in the access networks to open the bottleneck and thus present more opportunities for the provisioning of multiservices. Optical access solutions promise huge bandwidth to service providers and low-cost high-bandwidth services to end users and are therefore widely considered the technology of choice for next-generation access networks. To realize the vision of optical access networks, however, many key issues still need to be addressed, such as network architectures, signaling protocols, and implementation standards. The major challenges lie in the fact that an optical solution must be not only robust, scalable, and flexible, but also implemented at a low cost comparable to that of existing access solutions in order to increase the

  10. HRP Data Accessibility 2009

    NASA Video Gallery

    Dr. Clarence Sams spoke at the 2009 Human Research Program's Investigators Workshop on the current status of Data Accessibility. In this presentation he discusses the content of the Human Life Scie...

  11. Critical Access Hospitals (CAH)

    MedlinePlus

    ... CAH Conditions of Participation . What are the location requirements for CAH status? Critical Access Hospitals must be ... clinic that does not meet the CAH distance requirements? As of January 1, 2008, all CAHs, including ...

  12. Computer memory access technique

    NASA Technical Reports Server (NTRS)

    Zottarelli, L. J.

    1967-01-01

    Computer memory access commutator and steering gate configuration produces bipolar current pulses while still employing only the diodes and magnetic cores of the classic commutator, thereby appreciably reducing the complexity of the memory assembly.

  13. Adapting Web Browsers for Accessibility.

    ERIC Educational Resources Information Center

    Hendrix, Paul; Birkmire, Mike

    This paper examines ways to make World Wide Web browsers accessible for individuals with disabilities, and through them, gain access to the information on the Web. It discusses which browsers can be made more accessible and evaluates different types of input. Mouse access, keyboard access, and voice input are reviewed. Processing aids, such as…

  14. Optical Access Networks

    NASA Astrophysics Data System (ADS)

    Zheng, Jun; Ansari, Nirwan

    2005-02-01

    Call for Papers: Optical Access Networks With the wide deployment of fiber-optic technology over the past two decades, we have witnessed a tremendous growth of bandwidth capacity in the backbone networks of today's telecommunications infrastructure. However, access networks, which cover the "last-mile" areas and serve numerous residential and small business users, have not been scaled up commensurately. The local subscriber lines for telephone and cable television are still using twisted pairs and coaxial cables. Most residential connections to the Internet are still through dial-up modems operating at a low speed on twisted pairs. As the demand for access bandwidth increases with emerging high-bandwidth applications, such as distance learning, high-definition television (HDTV), and video on demand (VoD), the last-mile access networks have become a bandwidth bottleneck in today's telecommunications infrastructure. To ease this bottleneck, it is imperative to provide sufficient bandwidth capacity in the access networks to open the bottleneck and thus present more opportunities for the provisioning of multiservices. Optical access solutions promise huge bandwidth to service providers and low-cost high-bandwidth services to end users and are therefore widely considered the technology of choice for next-generation access networks. To realize the vision of optical access networks, however, many key issues still need to be addressed, such as network architectures, signaling protocols, and implementation standards. The major challenges lie in the fact that an optical solution must be not only robust, scalable, and flexible, but also implemented at a low cost comparable to that of existing access solutions in order to increase the economic viability of many potential high-bandwidth applications. In recent years, optical access networks have been receiving tremendous attention from both academia and industry. A large number of research activities have been carried out or

  15. Development of a clinical prediction rule to improve peripheral intravenous cannulae first attempt success in the emergency department and reduce post insertion failure rates: the Vascular Access Decisions in the Emergency Room (VADER) study protocol

    PubMed Central

    Carr, Peter J; Rippey, James C R; Cooke, Marie L; Bharat, Chrianna; Murray, Kevin; Higgins, Niall S; Foale, Aileen; Rickard, Claire M

    2016-01-01

    Introduction Peripheral intravenous cannula (PIVC) insertion is one of the most common clinical interventions performed in emergency care worldwide. However, factors associated with successful PIVC placement and maintenance are not well understood. This study seeks to determine the predictors of first time PIVC insertion success in emergency department (ED) and identify the rationale for removal of the ED inserted PIVC in patients admitted to the hospital ward. Reducing failed insertion attempts and improving peripheral intravenous cannulation practice could lead to better staff and patient experiences, as well as improving hospital efficiency. Methods and analysis We propose an observational cohort study of PIVC insertions in a patient population presenting to ED, with follow-up observation of the PIVC in subsequent admissions to the hospital ward. We will collect specific PIVC observational data such as; clinician factors, patient factors, device information and clinical practice variables. Trained researchers will gather ED PIVC insertion data to identify predictors of insertion success. In those admitted from the ED, we will determine the dwell time of the ED-inserted PIVC. Multivariate regression analyses will be used to identify factors associated with insertions success and PIVC failure and standard statistical validation techniques will be used to create and assess the effectiveness of a clinical predication rule. Ethics and dissemination The findings of our study will provide new evidence to improve insertion success rates in the ED setting and identify strategies to reduce premature device failure for patients admitted to hospital wards. Results will unravel a complexity of factors that contribute to unsuccessful PIVC attempts such as patient and clinician factors along with the products, technologies and infusates used. Trial registration number ACTRN12615000588594; Pre-results. PMID:26868942

  16. Mobile multiple access study

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Multiple access techniques (FDMA, CDMA, TDMA) for the mobile user and attempts to identify the current best technique are discussed. Traffic loading is considered as well as voice and data modulation and spacecraft and system design. Emphasis is placed on developing mobile terminal cost estimates for the selected design. In addition, design examples are presented for the alternative techniques of multiple access in order to compare with the selected technique.

  17. Access to health care

    PubMed Central

    Fortin, Martin; Maltais, Danielle; Hudon, Catherine; Lapointe, Lise; Ntetu, Antoine Lutumba

    2005-01-01

    OBJECTIVE To explore access to health care for patients presenting with multiple chronic conditions and to identify barriers and factors conducive to access. DESIGN Qualitative study with focus groups. SETTING Family practice unit in Chicoutimi (Saguenay), Que. PARTICIPANTS Twenty-five male and female adult patients with at least four chronic conditions but no cognitive disorders or decompensating conditions. METHODS For this pilot study, only three focus group discussions were held. MAIN FINDINGS The main barriers to accessing follow-up appointments included long waits on the telephone, automated telephone-answering systems, and needing to attend at specific times to obtain appointments. The main barriers to specialized care were long waiting times and the need to get prescriptions and referrals from family physicians. Factors reported conducive to access included systematic callbacks and the personal involvement of family physicians. Good communication between family physicians and specialists was also perceived to be an important factor in access. CONCLUSION Systematic callbacks, family physicians’ personal efforts to obtain follow-up visits, and better physician-specialist communication were all suggested as ways to improve access to care for patients with multiple chronic conditions. PMID:16926944

  18. Conducting Market Rate Surveys and Establishing Rate Policies.

    ERIC Educational Resources Information Center

    Karolak, Eric; Collins, Ray; Stoney, Louise

    Market rate surveys and the rate-setting policies and reimbursement rules informed by them are at the core of the market-based approach to child care and are central to the delicate balancing act of ensuring access to subsidized care while at the same time promoting the quality of child care. This report provides an overview of the market-based…

  19. Children with Moderate Acute Malnutrition with No Access to Supplementary Feeding Programmes Experience High Rates of Deterioration and No Improvement: Results from a Prospective Cohort Study in Rural Ethiopia

    PubMed Central

    James, Philip; Sadler, Kate; Wondafrash, Mekitie; Argaw, Alemayehu; Luo, Hanqi; Geleta, Benti; Kedir, Kiya; Getnet, Yilak; Belachew, Tefera; Bahwere, Paluku

    2016-01-01

    Background Children with moderate acute malnutrition (MAM) have an increased risk of mortality, infections and impaired physical and cognitive development compared to well-nourished children. In parts of Ethiopia not considered chronically food insecure there are no supplementary feeding programmes (SFPs) for treating MAM. The short-term outcomes of children who have MAM in such areas are not currently described, and there remains an urgent need for evidence-based policy recommendations. Methods We defined MAM as mid-upper arm circumference (MUAC) of ≥11.0cm and <12.5cm with no bilateral pitting oedema to include Ethiopian government and World Health Organisation cut-offs. We prospectively surveyed 884 children aged 6–59 months living with MAM in a rural area of Ethiopia not eligible for a supplementary feeding programme. Weekly home visits were made for seven months (28 weeks), covering the end of peak malnutrition through to the post-harvest period (the most food secure window), collecting anthropometric, socio-demographic and food security data. Results By the end of the study follow up, 32.5% (287/884) remained with MAM, 9.3% (82/884) experienced at least one episode of SAM (MUAC <11cm and/or bilateral pitting oedema), and 0.9% (8/884) died. Only 54.2% of the children recovered with no episode of SAM by the end of the study. Of those who developed SAM half still had MAM at the end of the follow up period. The median (interquartile range) time to recovery was 9 (4–15) weeks. Children with the lowest MUAC at enrolment had a significantly higher risk of remaining with MAM and a lower chance of recovering. Conclusions Children with MAM during the post-harvest season in an area not eligible for SFP experience an extremely high incidence of SAM and a low recovery rate. Not having a targeted nutrition-specific intervention to address MAM in this context places children with MAM at excessive risk of adverse outcomes. Further preventive and curative approaches

  20. Access to effective antimicrobials: a worldwide challenge.

    PubMed

    Laxminarayan, Ramanan; Matsoso, Precious; Pant, Suraj; Brower, Charles; Røttingen, John-Arne; Klugman, Keith; Davies, Sally

    2016-01-01

    Recent years have seen substantial improvements in life expectancy and access to antimicrobials, especially in low-income and lower-middle-income countries, but increasing pathogen resistance to antimicrobials threatens to roll back this progress. Resistant organisms in health-care and community settings pose a threat to survival rates from serious infections, including neonatal sepsis and health-care-associated infections, and limit the potential health benefits from surgeries, transplants, and cancer treatment. The challenge of simultaneously expanding appropriate access to antimicrobials, while restricting inappropriate access, particularly to expensive, newer generation antimicrobials, is unique in global health and requires new approaches to financing and delivering health care and a one-health perspective on the connections between pathogen transmission in animals and humans. Here, we describe the importance of effective antimicrobials. We assess the disease burden caused by limited access to antimicrobials, attributable to resistance to antimicrobials, and the potential effect of vaccines in restricting the need for antibiotics. PMID:26603918

  1. Microfibrillated cellulose: morphology and accessibility

    SciTech Connect

    Herrick, F.W.; Casebier, R.L.; Hamilton, J.K.; Sandberg, K.R.

    1983-01-01

    Microfibrillated cellulose (MFC) is prepared by subjecting dilute slurries of cellulose fibers to repeated high-pressure homogenizing action. A highly microfibrillated product will have a gel-like appearance at 2% concentration in water. Such gels have pseudoplastic viscosity properties and are very fluid when stirred at high shear rate. The relative viscosity of 2% MFC dispersions may be used as a measure of the degree of homogenization or microfibrillation of a given wood cellulose pulp. The water retention value of an MFC product can also be used as an indicator for degree of homogenization. Structurally, MFC appears to be a web of interconnected fibrils and microfibrils, the latter having diameters in the range 10-100 nm as observed in scanning and transmission electron micrographs. Chemical studies have revealed that MFC is only moderately degraded, while being greatly expanded in surface area. The accessibility of cellulose in MFC is only moderately degraded, while being greatly expanded in surface area. The accessibility of cellulose in MFC toward chemical reagents is greatly increased. Higher reactivity was demonstrated in dilute cupriethylenediamine solubility, triphenylmethylation, acetylation, periodate oxidation, and mineral acid and cellulase enzyme hydrolysis rates. 16 references, 8 figures, 7 tables.

  2. Preliminary experience for the evaluation of the intraoperative graft patency with real color charge-coupled device camera system: an advanced device for simultaneous capturing of color and near-infrared images during coronary artery bypass graft.

    PubMed

    Handa, Takemi; Katare, Rajesh G; Sasaguri, Shiro; Sato, Takayuki

    2009-08-01

    We developed a new color charge-coupled device (CCD) camera for the intraoperative indocyanine green (ICG) angiography. This device consists of a combination of custom-made optical filters and an ultra-high sensitive CCD image sensor, which can detect simultaneously color and near-infrared (NIR) rays from 380 to 1200 nm. We showed a comparison between our system and other devices for the preliminary experience. We routinely performed both transit-time flowmetry (TFM) and color images for intraoperative assessment, thallium-scintigraphy for the early postoperative assessment, and then angiography after 1-year surgery. We also obtained intraoperative graft flows and images in 116 grafts. Although TFM indicated a graft patency, the CCD camera suspected perfusion failures in four grafts. Also the analysis of the ICG fluorescence intensity showed the significant hypoperfusion at the perfusion territory distal to the anastomosis (graft vs. perfusion territory; 230+/-26 vs. 156+/-13 a.u, P=0.02). When the CCD camera suspected a graft failure, CCD camera and angiography showed a comparable graft failure. The unique device that visualized ICG-enhanced structures against a background of natural myocardial color improved the visibility of abnormality in flow and perfusion. Our findings show that this device may become a standard intraoperative graft and perfusion assessment tool in coronary artery bypass graft (CABG). PMID:19423513

  3. Space Station multiple access communications system

    NASA Technical Reports Server (NTRS)

    Olson, Nanci A.

    1986-01-01

    The development of a multiple access communications system (MACS) for the space-to-space communications on the Space Station is discussed. The communications capabilities of the FHMA, CDMA, TDMA, SDMA, and FDMA techniques are evaluated; FDMA was selected for the space-to-space communications on the Space Station because of its lower complexity and growth capability. The proposed space-to-space multiple access system for the Space Station is a digitally modulated Ku-band FDMA system with a distributed architecture; this system would transmit on frequencies between 13.4 and 13.7 GHz and receive on frequencies between 14.6 and 14.89 GHz, and the bandwidth will support seven high-data-rate users and 12 low-data-rate users. The IF components and antennas for the MACS are examined. A multiple access breadboard design is described.

  4. Advanced access appointments

    PubMed Central

    Hudec, John C.; MacDougall, Steven; Rankin, Elaine

    2010-01-01

    ABSTRACT OBJECTIVE To examine the effects of advanced access (same-day physician appointments) on patient and provider satisfaction and to determine its association with other variables such as physician income and patient emergency department use. DESIGN Patient satisfaction survey and semistructured interviews with physicians and support staff; analysis of physician medical insurance billings and patient emergency department visits. SETTING Cape Breton, NS. PARTICIPANTS Patients, physicians, and support staff of 3 comparable family physician practices that had not implemented advanced access and an established advanced access practice. MAIN OUTCOME MEASURES Self-reported provider and patient satisfaction, physician office income, and patients’ emergency department use. RESULTS The key benefits of implementation of advanced access were an increase in provider and patient satisfaction levels, same or greater physician office income, and fewer less urgent (triage level 4) and nonurgent (triage level 5) emergency department visits by patients. CONCLUSION Currently within the Central Cape Breton Region, 33% of patients wait 4 or more days for urgent appointments. Findings from this study can be used to enhance primary care physician practice redesign. This research supports many benefits of transitioning to an advanced access model of patient booking. PMID:20944024

  5. Research Investigation of Information Access Methods

    ERIC Educational Resources Information Center

    Heinrichs, John H.; Sharkey, Thomas W.; Lim, Jeen-Su

    2006-01-01

    This study investigates the satisfaction of library users at Wayne State University who utilize alternative information access methods. The LibQUAL+[TM] desired and perceived that satisfaction ratings are used to determine the user's "superiority gap." By focusing limited library resources to address "superiority gap" issues identified by each…

  6. Multiple-Access Quantum-Classical Networks

    NASA Astrophysics Data System (ADS)

    Razavi, Mohsen

    2011-10-01

    A multi-user network that supports both classical and quantum communication is proposed. By relying on optical code-division multiple access techniques, this system offers simultaneous key exchange between multiple pairs of network users. A lower bound on the secure key generation rate will be derived for decoy-state quantum key distribution protocols.

  7. File access prediction using neural networks.

    PubMed

    Patra, Prashanta Kumar; Sahu, Muktikanta; Mohapatra, Subasish; Samantray, Ronak Kumar

    2010-06-01

    One of the most vexing issues in design of a high-speed computer is the wide gap of access times between the memory and the disk. To solve this problem, static file access predictors have been used. In this paper, we propose dynamic file access predictors using neural networks to significantly improve upon the accuracy, success-per-reference, and effective-success-rate-per-reference by using neural-network-based file access predictor with proper tuning. In particular, we verified that the incorrect prediction has been reduced from 53.11% to 43.63% for the proposed neural network prediction method with a standard configuration than the recent popularity (RP) method. With manual tuning for each trace, we are able to improve upon the misprediction rate and effective-success-rate-per-reference using a standard configuration. Simulations on distributed file system (DFS) traces reveal that exact fit radial basis function (RBF) gives better prediction in high end system whereas multilayer perceptron (MLP) trained with Levenberg-Marquardt (LM) backpropagation outperforms in system having good computational capability. Probabilistic and competitive predictors are the most suitable for work stations having limited resources to deal with and the former predictor is more efficient than the latter for servers having maximum system calls. Finally, we conclude that MLP with LM backpropagation algorithm has better success rate of file prediction than those of simple perceptron, last successor, stable successor, and best k out of m predictors. PMID:20421183

  8. Open access and open source in chemistry

    PubMed Central

    Todd, Matthew H

    2007-01-01

    Scientific data are being generated and shared at ever-increasing rates. Two new mechanisms for doing this have developed: open access publishing and open source research. We discuss both, with recent examples, highlighting the differences between the two, and the strengths of both. PMID:17939849

  9. ISDC Data Access Layer

    NASA Astrophysics Data System (ADS)

    Jennings, D.; Borkowski, J.; Contessi, T.; Lock, T.; Rohlfs, R.; Walter, R.

    The ISDC Data Access Layer (DAL) is an ANSI C and \\fortran 90 compatible library under development in support of the ESA INTEGRAL mission data analysis software. DALs primary purpose is to isolate the analysis software from the specifics of the data formats while at the same time providing new data abstraction and access capabilities. DAL supports the creation and manipulation of hierarchical data sets which may span multiple files and, in theory, multiple computer systems. A number of Application Programming Interfaces (APIs) are supported by DAL that allow software to view and access data at different levels of complexity. DAL also allows data sets to reside on disk, in conventional memory or in shared memory in a way that is transparent to the user/application.

  10. Access to space studies

    NASA Technical Reports Server (NTRS)

    Martin, James A.

    1993-01-01

    The National Aeronautics and Space Administration is currently considering possible directions in Earth-to-orbit vehicle development under a study called 'Access to Space.' This agency-wide study is considering commercial launch vehicles, human transportation, space station logistics, and other space transportation requirements over the next 40 years. Three options are being considered for human transportation: continued use of the Space Shuttle; development of a small personnel carrier (personnel logistics system (PLS)); or development of an advanced vehicle such as a single-stage-to-orbit (SSTO). Several studies related to the overall Access to Space study are reported in this document.

  11. Accessibility | Smokefree.gov

    Cancer.gov

    Smokefree.gov is committed to providing access to all individuals—disabled or not—who are seeking information on its Web sites. To provide this information, the smokefree.gov Web site has been designed to comply with Section 508 of the Rehabilitation Act (as amended). Section 508 requires that all individuals with disabilities (whether they are federal government employees or members of the general public) have access to and use of information and data comparable to that provided to individuals without disabilities, unless an undue burden would be imposed.

  12. Migrants' access to healthcare.

    PubMed

    Norredam, Marie

    2011-10-01

    There are strong pragmatic and moral reasons for receiving societies to address access to healthcare for migrants. Receiving societies have a pragmatic interest in sustaining migrants' health to facilitate integration; they also have a moral obligation to ensure migrants' access to healthcare according to international human rights principles. The intention of this thesis is to increase the understanding of migrants' access to healthcare by exploring two study aims: 1) Are there differences in migrants' access to healthcare compared to that of non-migrants? (substudy I and II); and 2) Why are there possible differences in migrants' access to healthcare compared to that of non-migrants? (substudy III and IV). The thesis builds on different methodological approaches using both register-based retrospective cohort design, cross-sectional design and survey methods. Two different measures of access were used to explore differences: 1) cancer stage at diagnosis as a clinical outcome and 2) emergency room (ER) contacts as a utilisation measure. Both informal and formal barriers to access were studied to explore why possible differences existed including: 1) motivation for using ER; and 2) asylum seekers' healthcare entitlements. Different definitions of migration and ethnicity were investigated including: country of birth and residence status. Substudy I showed a tendency towards more advanced stage at diagnosis or unknown stage among most subgroups of migrant women with a history of cancer compared to non-migrant women. Sub-study II found that some migrants (those born in Somalia, Turkey and Ex-Yugoslavia) use ER services more frequently than do non-migrants whereas others have the same or lower utilisation levels. As a consequence, substudy III was undertaken, which documented that more migrant within all subgroups had considered contacting a primary caregiver before visiting the ER compared to non-migrants, but that migrants experienced communication problems herein

  13. Digital Scholarship and Open Access

    ERIC Educational Resources Information Center

    Losoff, Barbara; Pence, Harry E.

    2010-01-01

    Open access publications provide scholars with unrestricted access to the "conversation" that is the basis for the advancement of knowledge. The large number of open access journals, archives, and depositories already in existence demonstrates the technical and economic viability of providing unrestricted access to the literature that is the…

  14. Elementary School Computer Access, Socioeconomic Status, Ethnicity, and Grade 5 Student Achievement

    ERIC Educational Resources Information Center

    Barrett, Julie Ann

    2013-01-01

    Purpose: The purpose of this study was to describe the current school computer access rates of elementary school students and to determine the extent to which school computer access relates to academic achievement among Grade 5 students in the state of Texas. Specifically, the relationship of school computer access to student passing rates on the…

  15. Evolutionary Accessibility in Tunably Rugged Fitness Landscapes

    NASA Astrophysics Data System (ADS)

    Franke, Jasper; Krug, Joachim

    2012-09-01

    The adaptive evolution of a population under the influence of mutation and selection is strongly influenced by the structure of the underlying fitness landscape, which encodes the interactions between mutations at different genetic loci. Theoretical studies of such landscapes have been carried out for several decades, but only recently experimental fitness measurements encompassing all possible combinations of small sets of mutations have become available. The empirical studies have spawned new questions about the accessibility of optimal genotypes under natural selection. Depending on population dynamic parameters such as mutation rate and population size, evolutionary accessibility can be quantified through the statistics of accessible mutational pathways (along which fitness increases monotonically), or through the study of the basin of attraction of the optimal genotype under greedy (steepest ascent) dynamics. Here we investigate these two measures of accessibility in the framework of Kauffman's LK-model, a paradigmatic family of random fitness landscapes with tunable ruggedness. The key parameter governing the strength of genetic interactions is the number K of interaction partners of each of the L sites in the genotype sequence. In general, accessibility increases with increasing genotype dimensionality L and decreases with increasing number of interactions K. Remarkably, however, we find that some measures of accessibility behave non-monotonically as a function of K, indicating a special role of the most sparsely connected, non-trivial cases K=1 and 2. The relation between models for fitness landscapes and spin glasses is also addressed.

  16. Unique Access to Learning

    ERIC Educational Resources Information Center

    Goble, Don

    2009-01-01

    This article describes the many learning opportunities that broadcast technology students at Ladue Horton Watkins High School in St. Louis, Missouri, experience because of their unique access to technology and methods of learning. Through scaffolding, stepladder techniques, and trial by fire, students learn to produce multiple television programs,…

  17. Internet 2 Access Grid.

    ERIC Educational Resources Information Center

    Simco, Greg

    2002-01-01

    Discussion of the Internet 2 Initiative, which is based on collaboration among universities, businesses, and government, focuses on the Access Grid, a Computational Grid that includes interactive multimedia within high-speed networks to provide resources to enable remote collaboration among the research community. (Author/LRW)

  18. A matter of access

    PubMed Central

    Hu, Zheng; Chen, Kaifu; Li, Wei; Tyler, Jessica K

    2014-01-01

    The mechanism whereby transcriptional activators facilitate transcription activation has been debated. Our recent genome-wide profiling of gene expression during aging, where nucleosomes are depleted, indicates that the function of seemingly all transcriptional activators is to trigger nucleosome disassembly from promoters to allow the general transcription machinery access to the DNA. PMID:25764221

  19. Serving up Access

    ERIC Educational Resources Information Center

    Rich, Sarah

    2011-01-01

    When low-income students returned to Chicago public schools this fall, many had better access to technology, thanks to a public-private partnership. Chicago families with children enrolled in the National School Lunch Program are eligible for subsidized computers and Internet connections through an agreement between the city and telecom giant…

  20. ACCESS PENNSYLVANIA Curriculum Guide.

    ERIC Educational Resources Information Center

    Pennsylvania State Library, Harrisburg.

    This curriculum guide was prepared as a tool for teaching students the purpose and function of the ACCESS PENNSYLVANIA database in the total concept of information literacy. The database on compact laser disc contains information about the holdings of hundreds of school, public, academic, and special use libraries. The database can be searched at…

  1. Accessibility Standards, Illustrated.

    ERIC Educational Resources Information Center

    Jones, Michael A.

    The book sets forth Illinois environmental accessibility standards for disabled persons based on observation and interview data. Photographs, drawings, and detailed floor plans are included in sections dealing with human data (including space requirements for maneuvering wheelchairs, color blindness, incontinence, and severe auditory or visual…

  2. Partners: Promoting Accessible Recreation.

    ERIC Educational Resources Information Center

    Sable, Janet; Gravink, Jill

    1995-01-01

    The Promoting Accessible Recreation through Networking, Education, Resources and Services (PARTNERS) Project, a partnership between Northeast Passage, the University of New Hampshire, and Granite State Independent Living Foundation, helps create barrier-free recreation for individuals with physical disabilities. The paper describes PARTNERS and…

  3. Uniform Federal Accessibility Standards.

    ERIC Educational Resources Information Center

    Department of Housing and Urban Development, Washington, DC.

    The document presents uniform standards for facility accessibility by physically handicapped persons for Federal and federally funded facilities. The standards are to be applied during the design, construction, and alteration of buildings and facilities to the extent required by the Architectural Barriers Act of 1968, as amended. Technical…

  4. Improved Access to Learning.

    ERIC Educational Resources Information Center

    Miller, Sandra; Simkins, Michael

    2002-01-01

    Describes efforts by principal of the Willow Elementary School in the Charter Oak Unified School District (California) to provide students with technology-enhanced access to information and learning resources to improve reading and mathematics skills. Includes list of the Web addresses for the skills software used at the school. (PKP)

  5. CAS. Controlled Access Security

    SciTech Connect

    Martinez, B.; Pomeroy, G.

    1989-12-01

    The Security Alarm System is a data acquisition and control system which collects data from intrusion sensors and displays the information in a real-time environment for operators. The Access Control System monitors and controls the movement of personnel with the use of card readers and biometrics hand readers.

  6. ACCESS Project: Final Report

    SciTech Connect

    Weller, Heiko

    2015-04-01

    The ACCESS project addressed the development, testing, and demonstration of the proposed advanced technologies and the associated emission and fuel economy improvement at an engine dynamometer and on a full-scale vehicle. Improve fuel economy by 25% with minimum performance penalties Achieve SULEV level emissions with gasoline Demonstrate multi-mode combustion engine management system

  7. Strategies for Improving Access.

    ERIC Educational Resources Information Center

    Hore, Terry; Barwood, Bryan

    1989-01-01

    The development of the varied strategies that have been introduced in order to improve access for disadvantaged groups at Monash University is discussed. The Junior University Programme, the Monash Orientation Scheme for Aborigines, the Mature Age Special Admission Scheme, Special Entry Scheme, and the Schools Link Programme are described. (MLW)

  8. Access to Success

    ERIC Educational Resources Information Center

    Brunken, Anna; Delly, Pamela

    2011-01-01

    Changes to education in Australia have seen new government legislations increasing educational pathways so students can more easily enter university, the aim being to increase participation. Now, many domestic students utilise various pathways to access university. Some have undertaken basic Further Education Diplomas, received subject credits,…

  9. Base Rates: Both Neglected and Intuitive

    ERIC Educational Resources Information Center

    Pennycook, Gordon; Trippas, Dries; Handley, Simon J.; Thompson, Valerie A.

    2014-01-01

    Base-rate neglect refers to the tendency for people to underweight base-rate probabilities in favor of diagnostic information. It is commonly held that base-rate neglect occurs because effortful (Type 2) reasoning is required to process base-rate information, whereas diagnostic information is accessible to fast, intuitive (Type 1) processing…

  10. Fixed Access Network Sharing

    NASA Astrophysics Data System (ADS)

    Cornaglia, Bruno; Young, Gavin; Marchetta, Antonio

    2015-12-01

    Fixed broadband network deployments are moving inexorably to the use of Next Generation Access (NGA) technologies and architectures. These NGA deployments involve building fiber infrastructure increasingly closer to the customer in order to increase the proportion of fiber on the customer's access connection (Fibre-To-The-Home/Building/Door/Cabinet… i.e. FTTx). This increases the speed of services that can be sold and will be increasingly required to meet the demands of new generations of video services as we evolve from HDTV to "Ultra-HD TV" with 4k and 8k lines of video resolution. However, building fiber access networks is a costly endeavor. It requires significant capital in order to cover any significant geographic coverage. Hence many companies are forming partnerships and joint-ventures in order to share the NGA network construction costs. One form of such a partnership involves two companies agreeing to each build to cover a certain geographic area and then "cross-selling" NGA products to each other in order to access customers within their partner's footprint (NGA coverage area). This is tantamount to a bi-lateral wholesale partnership. The concept of Fixed Access Network Sharing (FANS) is to address the possibility of sharing infrastructure with a high degree of flexibility for all network operators involved. By providing greater configuration control over the NGA network infrastructure, the service provider has a greater ability to define the network and hence to define their product capabilities at the active layer. This gives the service provider partners greater product development autonomy plus the ability to differentiate from each other at the active network layer.

  11. Nosocomial infections in dialysis access.

    PubMed

    Schweiger, Alexander; Trevino, Sergio; Marschall, Jonas

    2015-01-01

    Nosocomial infections in patients requiring renal replacement therapy have a high impact on morbidity and mortality. The most dangerous complication is bloodstream infection (BSI) associated with the vascular access, with a low BSI risk in arteriovenous fistulas or grafts and a comparatively high risk in central venous catheters. The single most important measure for preventing BSI is therefore the reduction of catheter use by means of early fistula formation. As this is not always feasible, prevention should focus on educational efforts, hand hygiene, surveillance of dialysis-associated events, and specific measures at and after the insertion of catheters. Core measures at the time of insertion include choosing the optimal site of insertion, the use of maximum sterile barrier precautions, adequate skin antisepsis, and the choice of catheter type; after insertion, access care needs to ensure hub disinfection and regular dressing changes. The application of antimicrobial locks is reserved for special situations. Evidence suggests that bundling a selection of the aforementioned measures can significantly reduce infection rates. The diagnosis of central line-associated BSI (CLABSI) is based on clinical signs and microbiological findings in blood cultures ideally drawn both peripherally and from the catheter. The prompt installation of empiric antibiotic treatment covering the most commonly encountered organisms is key regarding CLABSI treatment. Catheter removal is recommended in complicated cases or if cultures yield Staphylococcus aureus, enterococci, Pseudomonas or fungi. In other cases, guide wire exchange or catheter salvage strategies with antibiotic lock solutions may be acceptable alternatives. PMID:25676304

  12. Endoscopic Ultrasound-Assisted Pancreaticobiliary Access.

    PubMed

    Weilert, Frank; Binmoeller, Kenneth F

    2015-10-01

    Endoscopic retrograde cholangiopancreatography (ERCP) is the primary approach to drain an obstructed pancreatic or biliary duct. Failed biliary drainage is traditionally referred for percutaneous transhepatic biliary drainage or surgical bypass, which carry significantly higher morbidity and mortality rates compared with ERCP and transpapillary drainage. Endoscopic ultrasound provides a real-time imaging platform to access and deliver therapy to organs and tissues outside of the bowel lumen. The bile and pancreatic ducts can be directly accessed from the stomach and duodenum, offering an alternative to ERCP when this fails or is not feasible. PMID:26431606

  13. Quantum internet using code division multiple access.

    PubMed

    Zhang, Jing; Liu, Yu-xi; Ozdemir, Sahin Kaya; Wu, Re-Bing; Gao, Feifei; Wang, Xiang-Bin; Yang, Lan; Nori, Franco

    2013-01-01

    A crucial open problem inS large-scale quantum networks is how to efficiently transmit quantum data among many pairs of users via a common data-transmission medium. We propose a solution by developing a quantum code division multiple access (q-CDMA) approach in which quantum information is chaotically encoded to spread its spectral content, and then decoded via chaos synchronization to separate different sender-receiver pairs. In comparison to other existing approaches, such as frequency division multiple access (FDMA), the proposed q-CDMA can greatly increase the information rates per channel used, especially for very noisy quantum channels. PMID:23860488

  14. Quantum internet using code division multiple access

    NASA Astrophysics Data System (ADS)

    Zhang, Jing; Liu, Yu-Xi; Özdemir, Şahin Kaya; Wu, Re-Bing; Gao, Feifei; Wang, Xiang-Bin; Yang, Lan; Nori, Franco

    2013-07-01

    A crucial open problem inS large-scale quantum networks is how to efficiently transmit quantum data among many pairs of users via a common data-transmission medium. We propose a solution by developing a quantum code division multiple access (q-CDMA) approach in which quantum information is chaotically encoded to spread its spectral content, and then decoded via chaos synchronization to separate different sender-receiver pairs. In comparison to other existing approaches, such as frequency division multiple access (FDMA), the proposed q-CDMA can greatly increase the information rates per channel used, especially for very noisy quantum channels.

  15. 19 CFR 351.604 - Access to information.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 3 2010-04-01 2010-04-01 false Access to information. 351.604 Section 351.604... DUTIES Subsidy Determinations Regarding Cheese Subject to an In-Quota Rate of Duty § 351.604 Access to information. Subpart C of this part applies to factual information submitted in connection with this subpart....

  16. Accessing Space Weather Information

    NASA Astrophysics Data System (ADS)

    Morrison, D.; Weiss, M.; Immer, E. A.; Patrone, D.; Potter, M.; Barnes, R. J.; Colclough, C.; Holder, R.

    2009-12-01

    To meet the needs of our technology based society, space weather forecasting needs to be advanced and this will entail collaboration amongst research, military and commercial communities to find new ways to understand, characterize, and forecast. In this presentation VITMO, the Virtual Ionosphere-Thermosphere-Mesosphere Observatory will be used as a prototype for a generalized system as a means to bring together a set of tools to access data, models and online collaboration tools to enable rapid progress. VITMO, available at http://vitmo.jhuapl.edu/, currently provides a data access portal for researchers and scientists to enable finding data products as well as access to tools and models. To further the needs of space weather forecasters, the existing VITMO data holdings need to be expanded to provide additional datasets as well as integrating relevant models and model output. VITMO can easily be adapted for the Space Weather domain in its entirety. In this presentation, we will demonstrate how VITMO and the VITMO architecture can be utilized as a prototype in support of integration of Space Weather forecasting tools, models and data.

  17. Working Concept of Accessibility

    PubMed Central

    Schroeder, Bastian J.; Rouphail, Nagui M.; Hughes, Ronald G.

    2010-01-01

    This research presents an analysis framework and associated performance measures for quantifying the accessibility of pedestrian crossings at modern roundabouts for pedestrians who are blind. The measures, developed under two ongoing national research projects, NCHRP Project 3-78A and a bioengineering research grant from the National Institutes of Health–National Eye Institute, attempt to isolate the components of the crossing task for a blind pedestrian into computable and replicable quantities that allow the comparison of accessibility across individuals or sites. The framework differentiates between crossing opportunities in the form of yields and crossable gaps and the utilization of these opportunities by the pedestrian. It further accounts for the amount of delay and risk involved in the crossing. The analysis framework and measures are demonstrated for two single-lane roundabouts in North Carolina evaluated under the aforementioned research projects. The application shows that the accessibility of a pedestrian crossing to a blind pedestrian is characterized by a combination of different measures and further depends on crossing geometry, traffic volume, driver behavior, and the travel skills and risk-taking behavior of the individual. With successful demonstration at roundabout crosswalks, the analysis framework is hypothesized to have broader application to unsignalized pedestrian crossings, including midblock locations. PMID:20664802

  18. Remote access thyroid surgery

    PubMed Central

    Bhatia, Parisha; Mohamed, Hossam Eldin; Kadi, Abida; Walvekar, Rohan R.

    2015-01-01

    Robot assisted thyroid surgery has been the latest advance in the evolution of thyroid surgery after endoscopy assisted procedures. The advantage of a superior field vision and technical advancements of robotic technology have permitted novel remote access (trans-axillary and retro-auricular) surgical approaches. Interestingly, several remote access surgical ports using robot surgical system and endoscopic technique have been customized to avoid the social stigma of a visible scar. Current literature has displayed their various advantages in terms of post-operative outcomes; however, the associated financial burden and also additional training and expertise necessary hinder its widespread adoption into endocrine surgery practices. These approaches offer excellent cosmesis, with a shorter learning curve and reduce discomfort to surgeons operating ergonomically through a robotic console. This review aims to provide details of various remote access techniques that are being offered for thyroid resection. Though these have been reported to be safe and feasible approaches for thyroid surgery, further evaluation for their efficacy still remains. PMID:26425450

  19. Digital imaging access library

    NASA Astrophysics Data System (ADS)

    Cook, Jay F.; Hansen, Mark; Francoise, James J.; Leckie, Robert G.; Smith, Donald V.

    1994-05-01

    The ability to access a vast array of radiological and pathologic diagnoses through computer searches of local medical facility databases is a by-product of the continued development of filmless imaging systems. The Department of Defense (DoD) Medical Diagnostic Imaging Support initiative is expanding through the addition of on-line systems at several DoD health care facilities. Madigan Army Medical Center, as the initial site, will soon be 90% filmless, with over one million images archived. Multiple other DoD medical centers are under installation. The eventual goal is an interconnected network of PACS systems of DoD medical centers and their supported medical facilities throughout the United States. To access this potential pool of medical information requires a centralized database capable of acting as a diagnostic index system. The establishment of a multi-center film library index begins with an initial analysis of issues regarding data storage and access, indexing, cross-coding with pathological files, communication formats, cost sharing, and patient confidentiality. In initiating these first steps to developing this telecommunications library these issues and their implications are discussed. The final implementation of this system will facilitate markedly improved research and teaching capabilities in both radiological and pathological fields.

  20. Research of Ad Hoc Networks Access Algorithm

    NASA Astrophysics Data System (ADS)

    Xiang, Ma

    With the continuous development of mobile communication technology, Ad Hoc access network has become a hot research, Ad Hoc access network nodes can be used to expand capacity of multi-hop communication range of mobile communication system, even business adjacent to the community, improve edge data rates. When the ad hoc network is the access network of the internet, the gateway discovery protocol is very important to choose the most appropriate gateway to guarantee the connectivity between ad hoc network and IP based fixed networks. The paper proposes a QoS gateway discovery protocol which uses the time delay and stable route to the gateway selection conditions. And according to the gateway discovery protocol, it also proposes a fast handover scheme which can decrease the handover time and improve the handover efficiency.

  1. After Access: Underrepresented Students' Postmatriculation Perceptions of College Access Capital

    ERIC Educational Resources Information Center

    Means, Darris R.; Pyne, Kimberly B.

    2016-01-01

    This qualitative study explores the perceived impact of college-going capital gained during participation in a college access program. In three, semistructured interviews spanning the first-year college experience, 10 first-year college students who participated in a college access program articulate the value of access programming and also raise…

  2. Ad Hoc Access Gateway Selection Algorithm

    NASA Astrophysics Data System (ADS)

    Jie, Liu

    With the continuous development of mobile communication technology, Ad Hoc access network has become a hot research, Ad Hoc access network nodes can be used to expand capacity of multi-hop communication range of mobile communication system, even business adjacent to the community, improve edge data rates. For mobile nodes in Ad Hoc network to internet, internet communications in the peer nodes must be achieved through the gateway. Therefore, the key Ad Hoc Access Networks will focus on the discovery gateway, as well as gateway selection in the case of multi-gateway and handover problems between different gateways. This paper considers the mobile node and the gateway, based on the average number of hops from an average access time and the stability of routes, improved gateway selection algorithm were proposed. An improved gateway selection algorithm, which mainly considers the algorithm can improve the access time of Ad Hoc nodes and the continuity of communication between the gateways, were proposed. This can improve the quality of communication across the network.

  3. Chemists, Access, Statistics

    NASA Astrophysics Data System (ADS)

    Holmes, Jon L.

    2000-06-01

    New JCE Internet Feature at JCE Online Biographical Snapshots of Famous Chemists is a new JCE Internet feature on JCE Online. Edited by Barbara Burke, this feature provides biographical information on leading chemists, especially women and minority chemists, fostering the attitude that the practitioners of chemistry are as human as those who endeavor to learn about it. Currently, the column features biographical "snapshots" of 30 chemists. Each snapshot includes keywords and bibliography and several contain links to additional online information about the chemist. More biographical snapshots will appear in future installments. In addition, a database listing over 140 women and minority chemists is being compiled and will be made available online with the snapshots in the near future. The database includes the years of birth and death, gender and ethnicity, major and minor discipline, keywords to facilitate searching, and references to additional biographical information. We welcome your input into what we think is a very worthwhile resource. If you would like to provide additional biographical snapshots, see additional chemists added to the database, or know of additional references for those that are already in the database, please contact JCE Online or the feature editor. Your feedback is welcome and appreciated. You can find Biographical Snapshots of Famous Chemists starting from the JCE Online home page-- click the Features item under JCE Internet and then the Chemist Bios item. Access JCE Online without Name and Password We have recently been swamped by libraries requesting IP-number access to JCE Online. With the great benefit IP-number authentication gives to librarians (no user names and passwords to administer) and to their patrons (no need to remember and enter valid names and passwords) this is not surprising. If you would like access to JCE Online without the need to remember and enter a user name and password, you should tell your librarian about our

  4. Intraosseous access in trauma by air medical retrieval teams.

    PubMed

    Sheils, Mark; Ross, Mark; Eatough, Noel; Caputo, Nicholas D

    2014-01-01

    Trauma accounts for a significant portion of overall mortality globally. Hemorrhage is the second major cause of mortality in the prehospital environment. Air medical retrieval services throughout the world have been developed to help improve the outcomes of patients suffering from a broad range of medical conditions, including trauma. These services often utilize intraosseous (IO) devices as an alternative means for access of both medically ill and traumatically injured patients in austere environments. However, studies have suggested that IO access cannot reach acceptable rates for massive transfusion. We review the subject to find the answer of whether IO access should be performed by air medical teams in the prehospital setting, or would central venous (CVC) access be more appropriate? We decided to assess the literature for capacity of IO access to meet resuscitation requirements in the prehospital management of trauma. We also decided to compare the insertion and complication characteristics of IO and CVC access. PMID:25049187

  5. Exchange Rates and Old People.

    ERIC Educational Resources Information Center

    Dowd, James J.

    1980-01-01

    Extends earlier work on aging as a process of exchange by focusing on the issue of exchange rates and how they are negotiated. Access to power resources declines with age, placing the old person in the position of negotiating from weakness. (Author)

  6. Utility of ventricular access in an acute deterioration after endoscopic third ventriculostomy.

    PubMed

    Kumar, A; Deopujari, C E; Biyani, N

    2011-01-01

    Endoscopic third ventriculostomy (ETV) has now been accepted widely as a safe procedure for treatment of non-communicating hydrocephalus. Despite its learning curve, most of the neurosurgeons have understood its technical details, benefits, and risks and have started to practice it to perfection. The benefit of shunt independence with minimal risks offers a remarkable advantage which has made this procedure widely popular. However, late closure of stoma leading to morbidity and even death has been reported off late. We report a case of a 7-year-old girl with hydrocephalus due to tectal glioma who deteriorated after 7 months following a successful procedure. She developed a cardio-respiratory arrest and was resuscitated with aspiration of cerebrospinal fluid from the ommaya reservoir kept during the primary surgery. Keeping all the patients under strict surveillance for stoma patency is mandatory and in addition, ommaya reservoir in certain high-risk patients may be a useful option for achieving quick ventricular access by medical and nonmedical personnel in case of deterioration. This case is the first reported case of acute deterioration after ETV from India. Previously, 14 such cases have been reported worldwide and only 2 of them have survived. PMID:21654134

  7. SDO Data Access And Analysis

    NASA Astrophysics Data System (ADS)

    Somani, A.; Hurlburt, N. E.; Schrijver, C. J.; Cheung, C.; Freeland, S. L.; Slater, G. L.; Seguin, R.; Timmons, R.; Green, S.; Chang, L.; Kobashi, A.; Jaffey, A.

    2010-12-01

    The Heliophysics Event Knowledgebase (HEK), Event Detection System (EDS), iSolSearch, Panorama, Event Viewer and Control Software (EVACS), and a variety of SolarSoft routines all work together to provide a suite of tools to facilitate access and analysis of SDO data. The HEK, which consists of the Heliophysics Event Registry (HER) and the Heliophysics Coverage Registry (HCR), uses XML formats built upon the IVOA VOEvent specification to ingest, store, and search events. Web services and SolarSoft routines are available to make use of these functions. The EDS is one of the sources that provides events for ingest into the HEK. The EDS continuously runs feature finding modules on SDO data. It's a distributed system that allows it to keep up with SDO's data rate. iSolSearch allows the user to browse the events in the HER and search for events given a specific time interval and other constraints. Panorama is the software tool used for rapid visualization of large volumes of solar image data in multiple channels/wavelengths. With the EVACS front-end GUI tool, Panorama allows the user to, in real-time, change channel pixel scaling, weights, alignment, blending and colorization of data. The user can also easily create WYSIWYG movies and launch the Annotator tool to describe events and features the user observes in the data. Panorama can also be used to drive clustered HiperSpace walls using the CGLX toolkit. Panorama harnesses the power of the GPU and OpenGL fragment shaders to enable stunning visualization. EVACS provides a JOGL powered GUI that the user can search both the HER and HCR with. EVACS displays the searched for events on a full disk magnetogram of the sun while displaying more detailed information for events. EVACS can also be used to launch Panorama with a selected set of FITS or PRGB files, as well as control many aspects of Panorama. A host of SolarSoft routines are available to not only access functions of the HEK, but to also access metadata and/or image

  8. Access to legal abortion.

    PubMed

    1993-10-01

    Countries are grouped by the nature and extent of access to legal abortion. The categories include abortion on demand, for social reasons, for health reasons, for rape or incest or to save a mother's life, and only to save a mother's life. Abortion on demand is available for about 40% of the world's population and may have restrictions, such as parental consent or approval of state committees or physicians. There are 22 countries in Europe, 12 in the former Soviet Union, four in Asia, four in the Americas, one in the Middle East (Turkey), and one in Africa (Tunisia) which provide access to early abortion on demand. Abortion for social and economic reasons is available to 21% of the world's population in five countries in Asia, three in Europe (Great Britain, Finland, and Hungary), and one in Africa (Zambia). Abortion for health reasons is available to 16% of the world's population located in 21 countries in Africa, eight in the Americas, seven in Asia, five in Europe, and four in the Middle East. Laws governing about 5% of the world's population permit abortion only in the case of rape, incest, or when a mother's life is in danger (Brazil, Mexico, and Sudan). 18% of the world's population is covered by laws which permit an abortion only when a mother's life is in danger; this includes 19 countries in Africa, 11 in the Americas, nine in Asia, seven in the Middle East, and one in Europe (Ireland). PMID:12287145

  9. Accessible magnetic resonance imaging.

    PubMed

    Kaufman, L; Arakawa, M; Hale, J; Rothschild, P; Carlson, J; Hake, K; Kramer, D; Lu, W; Van Heteren, J

    1989-10-01

    The cost of magnetic resonance imaging (MRI) is driven by magnetic field strength. Misperceptions as to the impact of field strength on performance have led to systems that are more expensive than they need to be. Careful analysis of all the factors that affect diagnostic quality lead to the conclusion that field strength per se is not a strong determinant of system performance. Freed from the constraints imposed by high-field operation, it is possible to exploit a varied set of opportunities afforded by low-field operation. In addition to lower costs and easier siting, we can take advantage of shortened T1 times, higher contrast, reduced sensitivity to motion, and reduced radiofrequency power deposition. These conceptual advantages can be made to coalesce onto practical imaging systems. We describe a low-cost MRI system that utilizes a permanent magnet of open design. Careful optimization of receiving antennas and acquisition sequences permit performance levels consistent with those needed for an effective diagnostic unit. Ancillary advantages include easy access to the patient, reduced claustrophobia, quiet and comfortable operation, and absence of a missile effect. The system can be sited in 350 sq ft and consumes a modest amount of electricity. MRI equipment of this kind can widen the population base than can access this powerful and beneficial diagnostic modality. PMID:2640910

  10. Connecting Related Rates and Differential Equations

    ERIC Educational Resources Information Center

    Brandt, Keith

    2012-01-01

    This article points out a simple connection between related rates and differential equations. The connection can be used for in-class examples or homework exercises, and it is accessible to students who are familiar with separation of variables.

  11. How To Secure E-Rate Funding.

    ERIC Educational Resources Information Center

    Dietrich, Donald

    2003-01-01

    Describes how to secure E-Rate funding from the Universal Service Administrative Company's School and Libraries Division (SLD) to help school districts obtain telecommunications and Internet access. The SLD Web site address is www.sl.universalservice.org. (PKP)

  12. Remote access astronomy

    NASA Astrophysics Data System (ADS)

    Beare, Richard; Bowdley, David; Newsam, Andrew; Roche, Paul

    2003-05-01

    There is still nothing to beat the excitement and fulfilment that you can get from observing celestial bodies on a clear dark night, in a remote location away from the seemingly ever increasing light pollution from cities. However, it is also the specific requirements for good observing that can sometimes prevent teachers from offering this opportunity to their students. Compromises for a town-based school or college might be to view only bright objects such as planets, or stars of magnitude 4 or brighter because of light pollution, but you would still require a knowledgeable teacher or astronomer and equipment to take outside with the students. Remote access astronomy using robotic telescopes can partly provide a solution to these problems and also opens up the doors to exciting projects that may otherwise be inaccessible to schools and colleges.

  13. Public Access and Open Access: Is There a Difference? | Poster

    Cancer.gov

    By Robin Meckley, Contributing Writer, and Tracie Frederick, Guest Writer Open access and public access—are they different concepts or are they the same? What do they mean for the researchers at NCI at Frederick? “Open-access (OA) literature is digital, online, free of charge, and free of most copyright and licensing restrictions. What makes it possible is the Internet and the consent of the author or copyright-holder,” according to an open access website maintained by Peter Suber, director, Harvard Open Access Project.

  14. Community variation in adolescent access to indoor tanning facilities.

    PubMed

    Olson, Ardis L; Carlos, Heather A; Sarnoff, Rachel A

    2013-04-01

    Melanoma rates among younger women in New Hampshire (NH) are rising. In urban studies, youth proximity to tanning facilities has been linked to indoor tanning, a proven cause of melanoma. Youth access has not been examined in rural settings. To determine on a statewide basis the influence of rurality and community income level on female students' ease of access to tanning facilities, all NH tanning facilities (N = 261) and high schools (N = 77) in 2011 were spatially and statistically analyzed to determine schools with more facilities within 2 miles of the school and greater capacity (fewer female students per facility), for indoor tanning. Schools above the state-wide average for both measures were classified as "Easy Access" to indoor tanning. Among NH high schools, 74 % have 1 or more tanning facility within two miles and 22 % have "Easy Access" to tanning facilities. Ease of access did not differ by rurality. Lower-income school status was an independent predictor of both greater capacity and "Easy Access". While urban and rural teens have similar access to indoor tanning, female students in lower-income communities have easier access. Variations in access by community size and income must be considered in planning interventions to address youth indoor tanning. PMID:23011517

  15. Agriculture: access to technology limited.

    PubMed

    1997-01-01

    From country to country and even regionally, the roles of women in agriculture vary, but most of their labor is in unpaid subsistence production and their contributions tend to be underestimated, according to the results of the [UN] Secretary-General's report. Depending on circumstances, they have complementary roles with men, sharing or dividing tasks in the production of crops, care of animals, and forestry management. In sub-Saharan Africa, for example, women contribute 60-80% of labor in food production for both household consumption and sale, while in Malaysia the women account for only 35% of the agricultural labor force, and in Ireland the participation rate is only 10.4%. Although women make this important amount of labor contributions to agricultural production, "development policies tend to favor export crops to earn foreign exchange and the agricultural research tends to address the improvement of production and technologies for commercial production". This results in limited access for women to technical knowledge and innovations, including irrigation, machinery, farming techniques and extension services. This is strengthened by the fact that most of the extension services target farmers who own land and can obtain credit to invest in input and technology. PMID:12293737

  16. Children's Access to Pre-School Education in Bangladesh

    ERIC Educational Resources Information Center

    Nath, Samir Ranjan; Sylva, Kathy

    2007-01-01

    Using the "Education Watch" household survey database, this paper explores children's access to pre-school education in Bangladesh. Participation in pre-school education has been increasing in Bangladesh at the rate of 0.6% per year and the net enrolment rate was found to be 13.4% in 2005. Enrolment of over-aged children in pre-school education…

  17. Accessible Online Learning

    ERIC Educational Resources Information Center

    Case, D. Elizabeth; Davidson, Roseanna C.

    2011-01-01

    The number of online courses offered at the postsecondary level is increasing at a rate greater than the increase in overall higher education enrollment, with approximately one of every four higher education students taking at least one course online (Allen and Seaman, 2009). In 2008, students with disabilities represented nearly 11% of all…

  18. Remote Data Access with IDL

    NASA Technical Reports Server (NTRS)

    Galloy, Michael

    2013-01-01

    A tool based on IDL (Interactive Data Language) and DAP (Data Access Protocol) has been developed for user-friendly remote data access. A difficulty for many NASA researchers using IDL is that often the data to analyze are located remotely and are too large to transfer for local analysis. Researchers have developed a protocol for accessing remote data, DAP, which is used for both SOHO and STEREO data sets. Server-side side analysis via IDL routine is available through DAP.

  19. 28 CFR 17.44 - Access eligibility.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Judicial Administration DEPARTMENT OF JUSTICE CLASSIFIED NATIONAL SECURITY INFORMATION AND ACCESS TO CLASSIFIED INFORMATION Access to Classified Information § 17.44 Access eligibility. (a) Determinations of eligibility for access to classified information are separate from suitability determinations with respect...

  20. 28 CFR 17.44 - Access eligibility.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Judicial Administration DEPARTMENT OF JUSTICE CLASSIFIED NATIONAL SECURITY INFORMATION AND ACCESS TO CLASSIFIED INFORMATION Access to Classified Information § 17.44 Access eligibility. (a) Determinations of eligibility for access to classified information are separate from suitability determinations with respect...

  1. Regional Webgis User Access Patterns Based on a Weighted Bipartite Network

    NASA Astrophysics Data System (ADS)

    Li, R.; Shen, Y.; Huang, W.; Wu, H.

    2015-07-01

    With the rapid development of geographic information services, Web Geographic Information Systems (WebGIS) have become an indispensable part of everyday life; correspondingly, map search engines have become extremely popular with users and WebGIS sites receive a massive volume of requests for access. These WebGIS users and the content accessed have regional characteristics; to understand regional patterns, we mined regional WebGIS user access patterns based on a weighted bipartite network. We first established a weighted bipartite network model for regional user access to a WebGIS. Then, based on the massive user WebGIS access logs, we clustered geographic information accessed and thereby identified hot access areas. Finally we quantitatively analyzed the access interests of regional users and the visitation volume characteristics of regional user access to these hot access areas in terms of user access permeability, user usage rate, and user access viscosity. Our research results show that regional user access to WebGIS is spatially aggregated, and the hot access areas that regional users accessed are associated with specific periods of time. Most regional user contact with hot accessed areas is variable and intermittent but for some users, their access to certain areas is continuous as it is associated with ongoing or recurrent objectives. The weighted bipartite network model for regional user WebGIS access provides a valid analysis method for studying user behaviour in WebGIS and the proposed access pattern exhibits access interest of regional user is spatiotemporal aggregated and presents a heavy-tailed distribution. Understanding user access patterns is good for WebGIS providers and supports better operational decision-making, and helpful for developers when optimizing WebGIS system architecture and deployment, so as to improve the user experience and to expand the popularity of WebGIS.

  2. Vehicle barrier with access delay

    DOEpatents

    Swahlan, David J; Wilke, Jason

    2013-09-03

    An access delay vehicle barrier for stopping unauthorized entry into secure areas by a vehicle ramming attack includes access delay features for preventing and/or delaying an adversary from defeating or compromising the barrier. A horizontally deployed barrier member can include an exterior steel casing, an interior steel reinforcing member and access delay members disposed within the casing and between the casing and the interior reinforcing member. Access delay members can include wooden structural lumber, concrete and/or polymeric members that in combination with the exterior casing and interior reinforcing member act cooperatively to impair an adversarial attach by thermal, mechanical and/or explosive tools.

  3. Atomic memory access hardware implementations

    SciTech Connect

    Ahn, Jung Ho; Erez, Mattan; Dally, William J

    2015-02-17

    Atomic memory access requests are handled using a variety of systems and methods. According to one example method, a data-processing circuit having an address-request generator that issues requests to a common memory implements a method of processing the requests using a memory-access intervention circuit coupled between the generator and the common memory. The method identifies a current atomic-memory access request from a plurality of memory access requests. A data set is stored that corresponds to the current atomic-memory access request in a data storage circuit within the intervention circuit. It is determined whether the current atomic-memory access request corresponds to at least one previously-stored atomic-memory access request. In response to determining correspondence, the current request is implemented by retrieving data from the common memory. The data is modified in response to the current request and at least one other access request in the memory-access intervention circuit.

  4. Nonvolatile random access memory

    NASA Technical Reports Server (NTRS)

    Wu, Jiin-Chuan (Inventor); Stadler, Henry L. (Inventor); Katti, Romney R. (Inventor)

    1994-01-01

    A nonvolatile magnetic random access memory can be achieved by an array of magnet-Hall effect (M-H) elements. The storage function is realized with a rectangular thin-film ferromagnetic material having an in-plane, uniaxial anisotropy and inplane bipolar remanent magnetization states. The thin-film magnetic element is magnetized by a local applied field, whose direction is used to form either a 0 or 1 state. The element remains in the 0 or 1 state until a switching field is applied to change its state. The stored information is detcted by a Hall-effect sensor which senses the fringing field from the magnetic storage element. The circuit design for addressing each cell includes transistor switches for providing a current of selected polarity to store a binary digit through a separate conductor overlying the magnetic element of the cell. To read out a stored binary digit, transistor switches are employed to provide a current through a row of Hall-effect sensors connected in series and enabling a differential voltage amplifier connected to all Hall-effect sensors of a column in series. To avoid read-out voltage errors due to shunt currents through resistive loads of the Hall-effect sensors of other cells in the same column, at least one transistor switch is provided between every pair of adjacent cells in every row which are not turned on except in the row of the selected cell.

  5. ACCESS: Detector Performance

    NASA Astrophysics Data System (ADS)

    Morris, Matthew J.; Kaiser, M.; Rauscher, B. J.; Kimble, R. A.; Kruk, J. W.; Mott, D. B.; Wen, Y.; Foltz, R.; McCandliss, S. R.; Pelton, R. S.; Wright, E. L.; Feldman, P. D.; Moos, H. W.; Riess, A. G.; Benford, D. J.; Gardner, J. P.; Woodgate, B. E.; Bohlin, R.; Deustua, S. E.; Dixon, W. V.; Sahnow, D. J.; Kurucz, R. L.; Lampton, M.; Perlmutter, S.

    2013-01-01

    ACCESS, Absolute Color Calibration Experiment for Standard Stars, is a series of rocket-borne sub-orbital missions and ground-based experiments that will enable improvements in the precision of the astrophysical flux scale through the transfer of absolute laboratory detector standards from the National Institute of Standards and Technology (NIST) to a network of stellar standards with a calibration accuracy of 1% and a spectral resolving power of 500 across the 0.35 to 1.7 micron bandpass (overview Kaiser et al.). The flight detector and detector spare have been integrated with their electronics and flight mount. The controller electronics have been flight qualified. Vibration testing to launch loads and thermal vacuum testing of the detector, mount, and housing have been performed. The flight detector controller boards have been installed into a ruggedized flight housing. They have been successfully vacuum tested for periods significantly longer than the flight length, and components have been heat-sunk and reinforced as necessary. Thermal stability tests have been performed, and results will be presented. Goddard Space Flight Center’s Detector Characterization Lab (DCL) executed initial characterization tests for the flight detector in 2007. These were repeated in 2012, to ensure and establish baseline performance. Current lab characterization tests at Johns Hopkins are ongoing, and results will be presented. NASA sounding rocket grant NNX08AI65G supports this work.

  6. Mobile access control vestibule

    NASA Astrophysics Data System (ADS)

    DePoy, Jennifer M.

    1998-12-01

    The mobile access control vestibule (MACV) is an adaptation of techniques developed for mobile military command centers. The overall configuration of modules acts as an entry control/screening facility or transportable command center. The system would provide the following capabilities: (1) A key element for force protection, rapid deployment units sent to areas having no prepositioned equipment or where there has been a degradation of that equipment as a result of natural disasters or civil unrest. (2) A rapidly deployable security control center to upgrade the security at nonmilitary sites (e.g., diplomatic or humanitarian organizations). (3) Personnel screening, package screening, badge/identification card production for authorized personnel, centralized monitoring of deployed perimeter sensors, and centralized communications for law enforcement personnel. (4) Self-contained screening and threat detection systems, including explosives detection using the system developed by Sandia National Laboratories for the FAA. When coupled with transportable electric generators, the system is self-sufficient. The communication system for the MACV would be a combination of physically wired and wireless communication units that supports by ad hoc networking.

  7. Education in vascular access.

    PubMed

    Moist, Louise M; Lee, Timmy C; Lok, Charmaine E; Al-Jaishi, Ahmed; Xi, Wang; Campbell, Vern; Graham, Janet; Wilson, Barb; Vachharajani, Tushar J

    2013-01-01

    The successful creation and use of an arteriovenous vascular access (VA) requires a coordinated, educated multidisciplinary team to ensure an optimal VA for each patient. Patient education programs on VA are associated with increased arteriovenous VA use at dialysis initiation. Education should be tailored to patient goals and preferences with the understanding that experiential education from patient to patient is far more influential than that provided by the healthcare professional. VA education for the nephrologist should focus on addressing the systematic and patient-level barriers in achieving a functional VA, with specific components relating to VA creation, maturation, and cannulation that consider patient goals and preferences. A deficit in nursing skills in the area of assessment and cannulation can have devastating consequences for hemodialysis patients. Delivery of an integrated education program increases nurses' knowledge of VA and development of simulation programs or constructs to assist in cannulation of the VA will greatly facilitate the much needed skill transfer. Adequate VA surgical training and experience are critical to the creation and outcomes of VA. Simulations can benefit nephrologists, dialysis nurses surgeons, and interventionalists though aiding in surgical creation, understanding of the physiology and anatomy of a dysfunctional VA, and practicing cannulation techniques. All future educational initiatives must emphasize the importance of multidisciplinary care to attain successful VA outcomes. PMID:23432319

  8. Access to space study

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This report summarizes the results of a comprehensive NASA in-house study to identify and assess alternate approaches to access to space through the year 2030, and to select and recommend a preferred cause of action. The goals of the study were to identify the best vehicles and transportation architectures to make major reductions in the cost of space transportation (at least 50%), while at the same time increasing safety for flight crews by at least an order of magnitude. In addition, vehicle reliability was to exceed 0.98 percent, and, as important, the robustness, pad time, turnaround time, and other aspects of operability were to be vastly improved. This study examined three major optional architectures: (1) retain and upgrade the Space Shuttle and expendable launch vehicles; (2) develop new expendable vehicles using conventional technologies and transition from current vehicles beginning in 2005; and (3) develop new reusable vehicles using advanced technology, and transition from current vehicles beginning in 2008. The launch-needs, mission model utilized for for the study was based upon today's projection of civil, defense, and commercial mission payload requirements.

  9. A quantum access network.

    PubMed

    Fröhlich, Bernd; Dynes, James F; Lucamarini, Marco; Sharpe, Andrew W; Yuan, Zhiliang; Shields, Andrew J

    2013-09-01

    The theoretically proven security of quantum key distribution (QKD) could revolutionize the way in which information exchange is protected in the future. Several field tests of QKD have proven it to be a reliable technology for cryptographic key exchange and have demonstrated nodal networks of point-to-point links. However, until now no convincing answer has been given to the question of how to extend the scope of QKD beyond niche applications in dedicated high security networks. Here we introduce and experimentally demonstrate the concept of a 'quantum access network': based on simple and cost-effective telecommunication technologies, the scheme can greatly expand the number of users in quantum networks and therefore vastly broaden their appeal. We show that a high-speed single-photon detector positioned at a network node can be shared between up to 64 users for exchanging secret keys with the node, thereby significantly reducing the hardware requirements for each user added to the network. This point-to-multipoint architecture removes one of the main obstacles restricting the widespread application of QKD. It presents a viable method for realizing multi-user QKD networks with efficient use of resources, and brings QKD closer to becoming a widespread technology. PMID:24005413

  10. Making Astronomy Accessible

    NASA Astrophysics Data System (ADS)

    Grice, Noreen A.

    2011-05-01

    A new semester begins, and your students enter the classroom for the first time. You notice a student sitting in a wheelchair or walking with assistance from a cane. Maybe you see a student with a guide dog or carrying a Braille computer. Another student gestures "hello” but then continues hand motions, and you realize the person is actually signing. You wonder why another student is using an electronic device to speak. Think this can't happen in your class? According to the U.S. Census, one out of every five Americans has a disability. And some disabilities, such as autism, dyslexia and arthritis, are considered "invisible” disabilities. This means you have a high probability that one of your students will have a disability. As an astronomy instructor, you have the opportunity to reach a wide variety of learners by using creative teaching strategies. I will share some suggestions on how to make astronomy and your part of the universe more accessible for everyone.

  11. Remote direct memory access

    DOEpatents

    Archer, Charles J.; Blocksome, Michael A.

    2012-12-11

    Methods, parallel computers, and computer program products are disclosed for remote direct memory access. Embodiments include transmitting, from an origin DMA engine on an origin compute node to a plurality target DMA engines on target compute nodes, a request to send message, the request to send message specifying a data to be transferred from the origin DMA engine to data storage on each target compute node; receiving, by each target DMA engine on each target compute node, the request to send message; preparing, by each target DMA engine, to store data according to the data storage reference and the data length, including assigning a base storage address for the data storage reference; sending, by one or more of the target DMA engines, an acknowledgment message acknowledging that all the target DMA engines are prepared to receive a data transmission from the origin DMA engine; receiving, by the origin DMA engine, the acknowledgement message from the one or more of the target DMA engines; and transferring, by the origin DMA engine, data to data storage on each of the target compute nodes according to the data storage reference using a single direct put operation.

  12. Ferroelectric random access memories.

    PubMed

    Ishiwara, Hiroshi

    2012-10-01

    Ferroelectric random access memory (FeRAM) is a nonvolatile memory, in which data are stored using hysteretic P-E (polarization vs. electric field) characteristics in a ferroelectric film. In this review, history and characteristics of FeRAMs are first introduced. It is described that there are two types of FeRAMs, capacitor-type and FET-type, and that only the capacitor-type FeRAM is now commercially available. In chapter 2, properties of ferroelectric films are discussed from a viewpoint of FeRAM application, in which particular attention is paid to those of Pb(Zr,Ti)O3, SrBi2Ta2O9, and BiFeO3. Then, cell structures and operation principle of the capacitor-type FeRAMs are discussed in chapter 3. It is described that the stacked technology of ferroelectric capacitors and development of new materials with large remanent polarization are important for fabricating high-density memories. Finally, in chapter 4, the optimized gate structure in ferroelectric-gate field-effect transistors is discussed and experimental results showing excellent data retention characteristics are presented. PMID:23421123

  13. Is Your Church Accessible? Houses of Worship: Physical Accessibility Checklist.

    ERIC Educational Resources Information Center

    Ensign, Arselia, Ed.

    1991-01-01

    This checklist is intended to help churches evaluate the accessibility of their facilities to those with physical disabilities. Categories covered are: basic accessibility, parking lots, walks, ramps, entrances/exits, doors and doorways, stairs and steps, floors, worship space, rest rooms, controls, water fountains, identification, warning…

  14. Access to Public Educational Facilities under the Equal Access Act.

    ERIC Educational Resources Information Center

    Wood, R. Craig; Goldblatt, Steven M.

    1988-01-01

    Discussion centers on the legal bases by which school administrators permit access to public educational facilities by religiously and politically oriented student organizations. It concludes that access should be granted to students whose purposes do not disrupt teaching and learning. (JAM)

  15. Self-Access Centers: Maximizing Learners' Access to Center Resources

    ERIC Educational Resources Information Center

    McMurry, Benjamin L.; Tanner, Mark W.; Anderson, Neil J.

    2009-01-01

    Although some students have discovered how to use self-access centers effectively, the majority appear to be unaware of available resources. A website and database of materials were created to help students locate materials and use the Self-Access Study Center (SASC) at Brigham Young University's English Language Center (ELC) more effectively.…

  16. Open and Endovascular Treatment of Trans-Atlantic Inter-Society Consensus II D Aortoiliac Occlusive Lesions: What Determines the Rate of Restenosis?

    PubMed Central

    Shen, Chen-Yang; Liu, Yun-Feng; Li, Qing-Le; Zhang, Yong-Bao; Jiao, Yang; Krokidis, Miltiadis E; Zhang, Xiao-Ming

    2015-01-01

    Background: Open surgery is the preferred approach for the treatment of type D lesions according to the Trans-Atlantic Inter-Society Consensus (TASC) II guideline, but endovascular solutions also appear to be a valid option in selected patients. The study aimed to identify the risk factors of restenosis after open and endovascular reconstruction of symptomatic TASC II D aortoiliac occlusive lesions (AIOLs). Methods: Fifty-six patients (82 limbs) who underwent open repair and endovascular treatment (ET) for symptomatic TASC ΙΙ D AIOLs between March 2005 and December 2012 were retrospectively reviewed. Baseline characteristics, preoperative and postoperative imaging, and operation procedure reports were reviewed and analyzed. Restenosis after revascularization was assessed by duplex ultrasound or computed tomography angiogram. Kaplan-Meier survival analysis, Log-rank test, and multivariate Cox regression were used to evaluate the relevance between risk factors and patency. Results: The mean duration of follow-up was 42.8 ± 23.5 months (ranging from 3 to 90 months). Primary patency rates at 1-, 3-, 5-, and 7-year were 93.6%, 89.3%, 87.0%, and 70.3%, respectively. Restenosis after revascularization occurred in 11 limbs. Kaplan-Meier survival analysis and the Log-rank test revealed that diabetes, Rutherford classification ≥5th and concurrent femoropopliteal TASC II type C/D lesions were significantly related to the duration of primary patency. According to the result of Cox regression, diabetes and femoropopliteal TASC ΙΙ type C/D lesions were identified as the risk factors for restenosis after revascularization. Conclusion: This study demonstrated that diabetes and femoropopliteal TASC ΙΙ type C/D lesions are risk factors associated with restenosis after open and ET of TASC II D AIOLs. PMID:26608983

  17. Clinical review: Vascular access for fluid infusion in children

    PubMed Central

    Haas, Nikolaus A

    2004-01-01

    The current literature on venous access in infants and children for acute intravascular access in the routine situation and in emergency or intensive care settings is reviewed. The various techniques for facilitating venous cannulation, such as application of local warmth, transillumination techniques and epidermal nitroglycerine, are described. Preferred sites for central venous access in infants and children are the external and internal jugular veins, the subclavian and axillary veins, and the femoral vein. The femoral venous cannulation appears to be the most safe and reliable technique in children of all ages, with a high success and low complication rates. Evidence from the reviewed literature strongly supports the use of real-time ultrasound techniques for venous cannulation in infants and children. Additionally, in emergency situations the intraosseous access has almost completly replaced saphenous cutdown procedures in children and has decreased the need for immediate central venous access. PMID:15566619

  18. The Table Access Protocol: Providing standard access to astronomical data

    NASA Astrophysics Data System (ADS)

    Nandrekar-Heinis, D.; Michel, L.; Louys, M.; Bonnarel, F.

    2014-11-01

    In the upcoming era of large scale, geographically distributed, varied sources of astronomical data, a standard, simple and flexible way to access this data is necessary and useful for astronomers across the globe. Most of the modern surveys such as the Sloan Digital Sky Survey (SDSS) are available in well organized tabular formats. The Table Access Protocol (TAP) supports a standard web interface to access this kind of tabular data. Predefined queries and results formats help different data providers to implement these services. TAP also helps various software tools to access data and perform cross-matches seamlessly across different data sources. It is then possible to access data in tools that consume TAP web services. This supports further detailed data analysis on a queried slice of data. This document describes TAP and its utility for astronomers and data scientists. It also provides information on the protocol for data providers and developers.

  19. Intraosseous approach to vascular access in adult resuscitation.

    PubMed

    Fenwick, Rob

    2010-07-01

    Establishing vascular access is vital to maximise resuscitation in critically ill children and adults (LaRocco and Wang 2003), and failure can result in delays in life-saving treatment (Nutbeam and Daniels 2010). The traditional intravenous access method can be difficult to achieve in patients with circulatory collapse (LaRocco and Wang 2003) and failure rates in emergency situations vary between 10 and 40 per cent (Lewis 1986). Other routes, such as endotracheal and intramuscular, do not provide controlled and reliable administration rates (Leidel et al 2009). This article focuses on the increased use of intraosseous (IO) access in adult resuscitation. The IO route is described and the indications and contraindications considered. Common insertion sites and devices of IO access are discussed. PMID:20662405

  20. Burdick's Technique for Biliary Access Revisited.

    PubMed

    Goenka, Mahesh Kumar; Rai, Vijay Kumar

    2015-01-01

    The precut sphincterotomy is used to facilitate selective biliary access in cases of difficult biliary cannulation. Needle-knife precut papillotomy is the standard of care but is associated with a high rate of complications such as pancreatitis, duodenal perforation, bleeding, etc. Sometimes during bowing of the sphincterotome/cannula and the use of guide wire to facilitate biliary cannulation, inadvertent formation of a false passage occurs in the 10 to 11 o'clock direction. Use of this step to access the bile duct by the intramucosal incision technique was first described by Burdick et al., and since then two more studies have also substantiated the safety and efficacy of this non-needle type of precut sphincterotomy. In this review, we discuss this non-needle technique of precut sphincterotomy and also share our experience using this "Burdick's technique." PMID:25674522

  1. Intravascular access in pediatric cardiac arrest.

    PubMed

    Brunette, D D; Fischer, R

    1988-11-01

    All cases of patients aged less than 48 months who presented in cardiac arrest to the Hennepin County Medical Center's emergency department (ED) during the years 1984 to 1986 were reviewed retrospectively. The ED record, initial and subsequent chest radiographs, hospital charts, and autopsy reports were analyzed. A total of 33 cases were reviewed. The average patient age was 5 months. The average time needed to establish intravascular access was 7.9 +/- 4.2 minutes. Success rates were 77% for central venous catheterization, 81% for surgical vein cutdown, 83% for intraosseous infusion, and 17% for percutaneous peripheral catheterization. Percutaneous peripheral catheterization, when successful, and bone marrow needle placement were the fastest methods of obtaining intravascular access. There were no major immediate complications, and delayed complications were minimal. Attempts at peripheral intravenous catheter placement should be brief, with rapid progression to intraosseous infusion if peripheral attempts are not successful. PMID:3178949

  2. Vascular access for hemodialysis: arteriovenous fistula.

    PubMed

    Malovrh, Marko

    2005-06-01

    The long-term survival and quality of life of patients on hemodialysis (HD) is dependant on the adequacy of dialysis via an appropriately placed vascular access. The optimal vascular access is unquestionably the autologous arteriovenous fistula (AVF), with the most common method being the conventional radio-cephalic fistula at the wrist. Recent clinical practice guidelines recommend the creation of native fistula or synthetic graft before the start of chronic HD therapy to prevent the need for complication-prone dialysis catheters. This could also have a beneficial effect on the rapidity of worsening kidney failure. A multidisciplinary approach (nephrologists, surgeons, radiologists and nurses) should improve the HD outcome by promoting the use of AVF. An important additional component of this program is the Doppler ultrasound for preoperative vascular mapping. Such an approach may be realized without unsuccessful surgical explorations, with a minimal early failure rate and a high maturation, even in patients with diabetes mellitus. PMID:15966992

  3. Evolutionary Accessibility of Modular Fitness Landscapes

    NASA Astrophysics Data System (ADS)

    Schmiegelt, B.; Krug, J.

    2013-10-01

    A fitness landscape is a mapping from the space of genetic sequences, which is modeled here as a binary hypercube of dimension L, to the real numbers. We consider random models of fitness landscapes, where fitness values are assigned according to some probabilistic rule, and study the statistical properties of pathways to the global fitness maximum along which fitness increases monotonically. Such paths are important for evolution because they are the only ones that are accessible to an adapting population when mutations occur at a low rate. The focus of this work is on the block model introduced by A.S. Perelson and C.A. Macken (Proc. Natl. Acad. Sci. USA 92:9657, 1995) where the genome is decomposed into disjoint sets of loci (`modules') that contribute independently to fitness, and fitness values within blocks are assigned at random. We show that the number of accessible paths can be written as a product of the path numbers within the blocks, which provides a detailed analytic description of the path statistics. The block model can be viewed as a special case of Kauffman's NK-model, and we compare the analytic results to simulations of the NK-model with different genetic architectures. We find that the mean number of accessible paths in the different versions of the model are quite similar, but the distribution of the path number is qualitatively different in the block model due to its multiplicative structure. A similar statement applies to the number of local fitness maxima in the NK-models, which has been studied extensively in previous works. The overall evolutionary accessibility of the landscape, as quantified by the probability to find at least one accessible path to the global maximum, is dramatically lowered by the modular structure.

  4. Internet Access to Spacecraft

    NASA Technical Reports Server (NTRS)

    Rash, James; Parise, Ron; Hogie, Keith; Criscuolo, Ed; Langston, Jim; Jackson, Chris; Price, Harold; Powers, Edward I. (Technical Monitor)

    2000-01-01

    The Operating Missions as Nodes on the Internet (OMNI) project at NASA's Goddard Space flight Center (GSFC), is demonstrating the use of standard Internet protocols for spacecraft communication systems. This year, demonstrations of Internet access to a flying spacecraft have been performed with the UoSAT-12 spacecraft owned and operated by Surrey Satellite Technology Ltd. (SSTL). Previously, demonstrations were performed using a ground satellite simulator and NASA's Tracking and Data Relay Satellite System (TDRSS). These activities are part of NASA's Space Operations Management Office (SOMO) Technology Program, The work is focused on defining the communication architecture for future NASA missions to support both NASA's "faster, better, cheaper" concept and to enable new types of collaborative science. The use of standard Internet communication technology for spacecraft simplifies design, supports initial integration and test across an IP based network, and enables direct communication between scientists and instruments as well as between different spacecraft, The most recent demonstrations consisted of uploading an Internet Protocol (IP) software stack to the UoSAT- 12 spacecraft, simple modifications to the SSTL ground station, and a series of tests to measure performance of various Internet applications. The spacecraft was reconfigured on orbit at very low cost. The total period between concept and the first tests was only 3 months. The tests included basic network connectivity (PING), automated clock synchronization (NTP), and reliable file transfers (FTP). Future tests are planned to include additional protocols such as Mobile IP, e-mail, and virtual private networks (VPN) to enable automated, operational spacecraft communication networks. The work performed and results of the initial phase of tests are summarized in this paper. This work is funded and directed by NASA/GSFC with technical leadership by CSC in arrangement with SSTL, and Vytek Wireless.

  5. Accessing the Internet Via Satellite.

    ERIC Educational Resources Information Center

    Jackson, Lisa M.

    1998-01-01

    Discusses the use of satellite technology as an option for public schools to access the Internet. Examines costs and available technology. Presents two examples of school-satellite usage, including its use by the Navajo Nation to provide Internet access for its students who are spread out across 26,000 square miles. (GR)

  6. Money, Equity, and College Access.

    ERIC Educational Resources Information Center

    Orfield, Gary

    1992-01-01

    Three decades after massive government commitment to financial aid, minority and low income access is declining and aid going to middle class students. Policies and political deadlock have worsened the situation of those in need, and hard choices must be made if college access is to be restored without greater expenditures. (SK)

  7. Bibliographic Access and Control System.

    ERIC Educational Resources Information Center

    Kelly, Betsy; And Others

    1982-01-01

    Presents a brief summary of the functions of the Bibliographic Access & Control System (BACS) implemented at the Washington University School of Medicine Library, and outlines the design, development, and uses of the system. Bibliographic control of books and serials and user access to the system are also discussed. (Author/JL)

  8. Advanced Placement: Access Not Exclusion.

    ERIC Educational Resources Information Center

    Camara, Wayne; Dorans, Neil J.; Morgan, Rick; Myford, Carol

    2000-01-01

    Refutes the assertion by W. Lichten (2000) that increased access to advanced placement (AP) courses in high school has led to a decline in AP quality. Suggests that increased access exposes students to college-level course material, encourages teachers to expand their knowledge domains, increases curriculum rigor, and give students new challenges.…

  9. ERIC Data Access System (EDAS).

    ERIC Educational Resources Information Center

    Rao, Pal V.

    The ERIC Data Access System (EDAS) is an information retrieval system developed at Eastern Illinois University to access the Educational Resources Information Center (ERIC) database and make it available to Eastern faculty and students in a convenient and timely fashion. This paper describes briefly why and how Eastern developed and implemented…

  10. Distributed Access to Administrative Systems.

    ERIC Educational Resources Information Center

    Carson, Eugene

    1987-01-01

    Administrators, faculty, and staff should have electronic access to records needed to perform their jobs, and students should have access to their own records--course registration and addresses. User-directed analysis and reporting are discussed and the security and audit issues are examined. (Author/MLW)

  11. Internet Accessibility in Latin America.

    ERIC Educational Resources Information Center

    Haymond, Ruel

    1998-01-01

    Addresses the problems that prohibit expanded Internet access and possible solutions to these problems, particularly with respect to the country of Chile. The three main problems that block Internet usage in Latin America are high demand and poor infrastructure; high costs for Internet access; and high preliminary costs for computers, modems, and…

  12. Accessibility on the Hudson River

    ERIC Educational Resources Information Center

    Exceptional Parent, 2010

    2010-01-01

    This article describes how Beverly and Martin Ryfa, working with an architect who specializes in accessible design, were able to build a house that is handicap accessible for their 9-year-old daughter, Danielle, who suffered an intraventricular hemorrhage when she was three days old. The article describes the features of their house that make…

  13. Accessible Multimedia for the Web.

    ERIC Educational Resources Information Center

    Zaparyniuk, Nicholas; Code, Jillianne

    With the Internet taking a dominant role in corporate training, education, retail, and customer based product exploration, authors of Web-based information need to ensure that the media they deliver is accessible to the widest possible audience. Whether users have a visual, auditory, physical, or developmental disability, accessible multimedia can…

  14. Open access: a closed shop?

    NASA Astrophysics Data System (ADS)

    Bradford, Rick

    2013-01-01

    Your December 2012 issue contains both a short news article on the progress of the open-access movement ("UK open access gains ground", p11) and a lengthy feature about the visionary Irish physicist Edward Hutchinson Synge ("Unknown genius", pp26-29). I find the combination of these articles ironic.

  15. Minority Access to Higher Education

    ERIC Educational Resources Information Center

    Jackson, Nathaniel

    2012-01-01

    Blacks, Hispanics, Native Americans, and Asian Americans are entitled to equal access to all institutions of higher education. Ensuring greater access and participation by minorities in higher education is one of the most practical ways of moving America closer to the ideal of equal opportunity, which is the actualization of the American dream.…

  16. Hearing Loss and Older Adults’ Perceptions of Access to Care

    PubMed Central

    Schumacher, Jessica R.; Barnett, Steven; Smith, Maureen A.

    2011-01-01

    We investigated whether hard-of-hearing older adults were more likely to report difficulties and delays in accessing care and decreased satisfaction with healthcare access than those without hearing loss. The Wisconsin Longitudinal Study (2003–2006 wave, N = 6,524) surveyed respondents regarding hearing, difficulties/delays in accessing care, satisfaction with healthcare access, socio-demographics, chronic conditions, self-rated health, depression, and length of relationship with provider/site. We used multivariate regression to compare access difficulties/delays and satisfaction by respondents’ hearing status (hard-of-hearing or not). Hard-of-hearing individuals comprised 18% of the sample. Compared to those not hard-of-hearing, hard-of-hearing individuals were significantly more likely to be older, male and separated/divorced. They had a higher mean number of chronic conditions, including atherosclerotic vascular disease, diabetes and depression. After adjustment for potential confounders, hard-of-hearing individuals were more likely to report difficulties in accessing healthcare (Odds Ratio 1.85; 95% Confidence Interval 1.19–2.88). Satisfaction with healthcare access was similar in both groups. Our findings suggest healthcare access difficulties will be heightened for more of the population because of the increasing prevalence of hearing loss. The prevalence of hearing loss in this data is low and our findings from a telephone survey likely underestimate the magnitude of access difficulties experienced by hard-of-hearing older adults. Further research which incorporates accessible surveys is needed. In the meantime, clinicians should pay particular attention to assessing barriers in healthcare access for hard-of-hearing individuals. Resources should be made available to proactively address these issues for those who are hard-of-hearing and to educate providers about the specific needs of this population. PMID:21301940

  17. Success Factors for Open Access

    PubMed Central

    2003-01-01

    Open access to the peer-reviewed primary research literature would greatly facilitate knowledge transfer between the creators and the users of the results of research and scholarship. Criteria are needed to assess the impact of recent initiatives, such as the Budapest Open Access Initiative. For example, how many open-access research journals exist within a given field, and what is the reputation of each one? And, how many openly-accessible institutional e-print archives have been created and how many are actually are being used by researchers and scholars? A simple approach to an assessment of the open-access portion of the medical literature is described, and some preliminary results are summarized. These preliminary results point to the need for incentives to foster the implementation of initiatives such as the Budapest Open Access Initiative. An example of an incentive model is proposed, where an agency or foundation that provides peer-reviewed grants-in-aid to researchers establishes an e-print archive. Only current grantees of the agency would be eligible to post reports about the results of research projects or programs that have been supported by the agency. Some advantages and implications of this particular model are outlined. It is suggested that incentive models of this kind are needed to increase the likelihood that open access to the primary medical research literature will soon reach a "tipping point" and move quickly toward wide acceptance. PMID:12746206

  18. Success factors for open access.

    PubMed

    Till, James E

    2003-01-01

    Open access to the peer-reviewed primary research literature would greatly facilitate knowledge transfer between the creators and the users of the results of research and scholarship. Criteria are needed to assess the impact of recent initiatives, such as the Budapest Open Access Initiative. For example, how many open-access research journals exist within a given field, and what is the reputation of each one? And, how many openly-accessible institutional e-print archives have been created and how many are actually are being used by researchers and scholars? A simple approach to an assessment of the open-access portion of the medical literature is described, and some preliminary results are summarized. These preliminary results point to the need for incentives to foster the implementation of initiatives such as the Budapest Open Access Initiative. An example of an incentive model is proposed, where an agency or foundation that provides peer-reviewed grants-in-aid to researchers establishes an e-print archive. Only current grantees of the agency would be eligible to post reports about the results of research projects or programs that have been supported by the agency. Some advantages and implications of this particular model are outlined. It is suggested that incentive models of this kind are needed to increase the likelihood that open access to the primary medical research literature will soon reach a "tipping point" and move quickly toward wide acceptance. PMID:12746206

  19. Data Access Performance Through Parallelization and Vectored Access: Some Results

    SciTech Connect

    Furano, Fabrizio; Hanushevsky, Andrew; /SLAC

    2011-11-10

    High Energy Physics data processing and analysis applications typically deal with the problem of accessing and processing data at high speed. Recent studies, development and test work have shown that the latencies due to data access can often be hidden by parallelizing them with the data processing, thus giving the ability to have applications which process remote data with a high level of efficiency. Techniques and algorithms able to reach this result have been implemented in the client side of the Scalla/xrootd system, and in this contribution we describe the results of some tests done in order to compare their performance and characteristics. These techniques, if used together with multiple streams data access, can also be effective in allowing to efficiently and transparently deal with data repositories accessible via a Wide Area Network.

  20. Database Access Integration Services (DAIS)

    SciTech Connect

    Mitchell, P. . Sensor and System Development Center); Nordell, D. )

    1992-12-01

    The Database Access Integration Services (DAIS) is a collection of services that facilitate access to data among diverse data systems in an electric utility communications network. DAIS provides access to data in distributed, heterogeneous data systems that include relational database management systems, other database management systems, control systems, file systems, and application systems. It also provides a common method for describing data, common data access operations and essential support services including a data dictionary, a data directory and distributed data access management capabilities. The DAIS project has developed specifications intended for vendor and third-party implementation. The software developed is only to implement a data access integration demonstration. These specifications can serve as a basis for influencing industry standards development. One important consequence of this strategy is that most actual software development will be performed by vendors, not utilities. DAIS is a tool to support data access. It is policy neutral regarding issues such as local or central administration of data or standardization of information model contents (e.g., EPRI Plant Information Network). As a tool, it can be used to help realize such policies. The DAIS does not provide data storage facilities, schema integration, distributed query processing, distributed applications or cooperative processing. Rather, DAIS is complementary to these functions and can be used with other software that does provide these functions. This project documented the requirements for the DAIS. These requirements are the basis for design of the DAIS specifications. The key requirements for a DAIS are: Uniform access to heterogeneous utility data systems, remote update; coexistence with local data systems; local autonomy ; Security and access restriction enforcement; OSI compatibility; open architecture and extensibility; and operating platform independence.

  1. [Intraosseous access in adults--an alternative if conventional vascular access is difficult?].

    PubMed

    Isbye, Dan Lou; Nielsen, Søren Loumann

    2006-08-21

    Intraosseous infusion is widely used in children, but its use in adults is much less common. This is probably because another vascular access can usually be achieved, and also because of lack of knowledge of the technique. Placement in adults is a quick procedure with a high rate of success. Drugs and fluids do not change the pharmacodynamics or pharmacokinetics of intraosseous administration, and anything can be given. Infusion rates have been achieved that in part make fluid resuscitation possible. Its uses are many and the contraindications few; complications are rare when simple guidelines are followed. PMID:16942698

  2. Perceived accessibility versus actual physical accessibility of healthcare facilities.

    PubMed

    Sanchez, J; Byfield, G; Brown, T T; LaFavor, K; Murphy, D; Laud, P

    2000-01-01

    This study addressed how healthcare clinics perceive themselves in regard to accessibility for persons with spinal cord injuries (SCI). All 40 of the clinics surveyed reported that they were wheelchair accessible; however, there was significant variability in the number of sites that actually met the guidelines of the Americans with Disability Act. In general, a person using a wheelchair could enter the building, the examination room, and the bathroom. The majority of sites did not have an examination table that could be lowered to wheelchair level. Most reported limited experience in working with persons with (SCI), yet they claimed to be able to assist with difficult transfers. Only one site knew about autonomic dysreflexia. Problems of accessibility appeared to be seriously compounded by the clinics' perception of how they met physical accessibility guidelines without consideration of the actual needs of persons with SCI. This study addressed the perception of accessibility as reported by clinic managers versus actual accessibility in healthcare clinics in a Midwestern metropolitan area for persons using wheelchairs. PMID:10754921

  3. Interoperable Data Access Services for NOAA IOOS

    NASA Astrophysics Data System (ADS)

    de La Beaujardiere, J.

    2008-12-01

    The Integrated Ocean Observing System (IOOS) is intended to enhance our ability to collect, deliver, and use ocean information. The goal is to support research and decision-making by providing data on our open oceans, coastal waters, and Great Lakes in the formats, rates, and scales required by scientists, managers, businesses, governments, and the public. The US National Oceanic and Atmospheric Administration (NOAA) is the lead agency for IOOS. NOAA's IOOS office supports the development of regional coastal observing capability and promotes data management efforts to increase data accessibility. Geospatial web services have been established at NOAA data providers including the National Data Buoy Center (NDBC), the Center for Operational Oceanographic Products and Services (CO-OPS), and CoastWatch, and at regional data provider sites. Services established include Open-source Project for a Network Data Access Protocol (OpenDAP), Open Geospatial Consortium (OGC) Sensor Observation Service (SOS), and OGC Web Coverage Service (WCS). These services provide integrated access to data holdings that have been aggregated at each center from multiple sources. We wish to collaborate with other groups to improve our service offerings to maximize interoperability and enhance cross-provider data integration, and to share common service components such as registries, catalogs, data conversion, and gateways. This paper will discuss the current status of NOAA's IOOS efforts and possible next steps.

  4. Open Access Publishing in Astronomy

    NASA Astrophysics Data System (ADS)

    Grothkopf, U.; Meakins, S.

    2012-08-01

    Open Access (OA) in scholarly literature means the "immediate, free availability on the public internet, permitting any users to read, download, copy, distribute, print, search or link to the full text of these articles". The Open Access movement has been made possible thanks to the wide-spread availability of internet access and has received increasing interest since the 1990s, mostly due to the fast rising journal subscription prices. This presentation will review the current situation of Open Access in astronomy. It will answer the question why it makes sense to publish in an OA journal and will provide criteria to judge the quality of OA journals and publishers, along with suggestions how to identify so-called predatory publishers.

  5. Astronauts Access Web from Space

    NASA Video Gallery

    Aboard the International Space Station, Expedition 22 Commander Jeff Williams and Flight Engineers Soichi Noguchi and T.J. Creamer share their thoughts about Internet access from space and post a r...

  6. Computer Security Systems Enable Access.

    ERIC Educational Resources Information Center

    Riggen, Gary

    1989-01-01

    A good security system enables access and protects information from damage or tampering, but the most important aspects of a security system aren't technical. A security procedures manual addresses the human element of computer security. (MLW)

  7. Computer access security code system

    NASA Technical Reports Server (NTRS)

    Collins, Earl R., Jr. (Inventor)

    1990-01-01

    A security code system for controlling access to computer and computer-controlled entry situations comprises a plurality of subsets of alpha-numeric characters disposed in random order in matrices of at least two dimensions forming theoretical rectangles, cubes, etc., such that when access is desired, at least one pair of previously unused character subsets not found in the same row or column of the matrix is chosen at random and transmitted by the computer. The proper response to gain access is transmittal of subsets which complete the rectangle, and/or a parallelepiped whose opposite corners were defined by first groups of code. Once used, subsets are not used again to absolutely defeat unauthorized access by eavesdropping, and the like.

  8. UK to support open access

    NASA Astrophysics Data System (ADS)

    Banks, Michael

    2012-08-01

    The UK government has "widely accepted" the recommendations of a major report into open-access publishing that was released in June by a 15-strong working group led by the British sociologist Janet Finch.

  9. Just the Facts: Vascular Access

    MedlinePlus

    ... vein thicker so it can be used for dialysis. A fistula is often the longest-lasting access. ... Artery Graft Illustration from Core Curriculum for the Dialysis Technician , 1998 Vein A catheter is a plastic ...

  10. 10 CFR 1017.19 - Access limitations.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... INFORMATION Access to Unclassified Controlled Nuclear Information § 1017.19 Access limitations. A person may only have access to UCNI if he or she has been granted routine access by an Authorized Individual (see... 10 Energy 4 2010-01-01 2010-01-01 false Access limitations. 1017.19 Section 1017.19...

  11. 47 CFR 76.702 - Public access.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Public access. 76.702 Section 76.702... CABLE TELEVISION SERVICE Cable Television Access § 76.702 Public access. A cable operator may refuse to transmit any public access program or portion of a public access program that the operator...

  12. 10 CFR 1017.21 - Limited access.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... INFORMATION Access to Unclassified Controlled Nuclear Information § 1017.21 Limited access. (a) A person who is not eligible for routine access to specific UCNI under § 1017.20 may request limited access to... 10 Energy 4 2010-01-01 2010-01-01 false Limited access. 1017.21 Section 1017.21 Energy...

  13. 32 CFR 154.49 - Granting access.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... SECURITY PROGRAM REGULATION Issuing Clearance and Granting Access § 154.49 Granting access. (a) Access to classified information shall be granted to persons whose official duties require such access and who have the... 32 National Defense 1 2011-07-01 2011-07-01 false Granting access. 154.49 Section 154.49...

  14. 47 CFR 76.702 - Public access.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 4 2011-10-01 2011-10-01 false Public access. 76.702 Section 76.702... CABLE TELEVISION SERVICE Cable Television Access § 76.702 Public access. A cable operator may refuse to transmit any public access program or portion of a public access program that the operator...

  15. 32 CFR 154.49 - Granting access.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... SECURITY PROGRAM REGULATION Issuing Clearance and Granting Access § 154.49 Granting access. (a) Access to classified information shall be granted to persons whose official duties require such access and who have the... 32 National Defense 1 2010-07-01 2010-07-01 false Granting access. 154.49 Section 154.49...

  16. 10 CFR 1017.21 - Limited access.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... INFORMATION Access to Unclassified Controlled Nuclear Information § 1017.21 Limited access. (a) A person who is not eligible for routine access to specific UCNI under § 1017.20 may request limited access to... 10 Energy 4 2011-01-01 2011-01-01 false Limited access. 1017.21 Section 1017.21 Energy...

  17. 10 CFR 1017.19 - Access limitations.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... INFORMATION Access to Unclassified Controlled Nuclear Information § 1017.19 Access limitations. A person may only have access to UCNI if he or she has been granted routine access by an Authorized Individual (see... 10 Energy 4 2011-01-01 2011-01-01 false Access limitations. 1017.19 Section 1017.19...

  18. 32 CFR 154.49 - Granting access.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 1 2013-07-01 2013-07-01 false Granting access. 154.49 Section 154.49 National... SECURITY PROGRAM REGULATION Issuing Clearance and Granting Access § 154.49 Granting access. (a) Access to classified information shall be granted to persons whose official duties require such access and who have...

  19. 32 CFR 154.49 - Granting access.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 1 2012-07-01 2012-07-01 false Granting access. 154.49 Section 154.49 National... SECURITY PROGRAM REGULATION Issuing Clearance and Granting Access § 154.49 Granting access. (a) Access to classified information shall be granted to persons whose official duties require such access and who have...

  20. 5 CFR 2606.203 - Granting access.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Granting access. 2606.203 Section 2606... Access to Records and Accounting of Disclosures § 2606.203 Granting access. (a) The methods for allowing access to records, when such access has been granted by OGE or the other agency concerned are:...

  1. 5 CFR 2606.203 - Granting access.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 3 2011-01-01 2011-01-01 false Granting access. 2606.203 Section 2606... Access to Records and Accounting of Disclosures § 2606.203 Granting access. (a) The methods for allowing access to records, when such access has been granted by OGE or the other agency concerned are:...

  2. 5 CFR 2606.203 - Granting access.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 3 2012-01-01 2012-01-01 false Granting access. 2606.203 Section 2606... Access to Records and Accounting of Disclosures § 2606.203 Granting access. (a) The methods for allowing access to records, when such access has been granted by OGE or the other agency concerned are:...

  3. 5 CFR 2606.203 - Granting access.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 3 2014-01-01 2014-01-01 false Granting access. 2606.203 Section 2606... Access to Records and Accounting of Disclosures § 2606.203 Granting access. (a) The methods for allowing access to records, when such access has been granted by OGE or the other agency concerned are:...

  4. 32 CFR 154.49 - Granting access.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 1 2014-07-01 2014-07-01 false Granting access. 154.49 Section 154.49 National... SECURITY PROGRAM REGULATION Issuing Clearance and Granting Access § 154.49 Granting access. (a) Access to classified information shall be granted to persons whose official duties require such access and who have...

  5. Preparing for the New Remote Access.

    ERIC Educational Resources Information Center

    Taylor, William E.

    1997-01-01

    Integrated remote access servers support many different types of access. Remote access has been integrated as a strategic tool as application developers build remote access capabilities into their software. Discusses demands of using remote access as a strategic component and management matters. (AEF)

  6. 47 CFR 76.702 - Public access.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 4 2013-10-01 2013-10-01 false Public access. 76.702 Section 76.702... CABLE TELEVISION SERVICE Cable Television Access § 76.702 Public access. A cable operator may refuse to transmit any public access program or portion of a public access program that the operator...

  7. 47 CFR 76.702 - Public access.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 4 2014-10-01 2014-10-01 false Public access. 76.702 Section 76.702... CABLE TELEVISION SERVICE Cable Television Access § 76.702 Public access. A cable operator may refuse to transmit any public access program or portion of a public access program that the operator...

  8. Holistic Approaches to E-Learning Accessibility

    ERIC Educational Resources Information Center

    Phipps, Lawrie; Kelly, Brian

    2006-01-01

    The importance of accessibility to digital e-learning resources is widely acknowledged. The World Wide Web Consortium Web Accessibility Initiative has played a leading role in promoting the importance of accessibility and developing guidelines that can help when developing accessible web resources. The accessibility of e-learning resources…

  9. Accessible solitons of fractional dimension

    NASA Astrophysics Data System (ADS)

    Zhong, Wei-Ping; Belić, Milivoj; Zhang, Yiqi

    2016-05-01

    We demonstrate that accessible solitons described by an extended Schrödinger equation with the Laplacian of fractional dimension can exist in strongly nonlocal nonlinear media. The soliton solutions of the model are constructed by two special functions, the associated Legendre polynomials and the Laguerre polynomials in the fraction-dimensional space. Our results show that these fractional accessible solitons form a soliton family which includes crescent solitons, and asymmetric single-layer and multi-layer necklace solitons.

  10. [The concepts of health access].

    PubMed

    Sanchez, Raquel Maia; Ciconelli, Rozana Mesquita

    2012-03-01

    This article describes four dimensions of health access-availability, acceptability, ability to pay and information-correlating these dimensions to indicators and discussing the complexity of the concept of access. For a study of these four dimensions, searches were conducted using the PubMed/MEDLINE, LILACS, SciELO, and World Health Organization Library & Information Networks for Knowledge (WHOLIS) databases. Large-circulation media vehicles, such as The Economist, The Washington Post, and the BBC network were also searched. The concept of health access has become more complex with time. The first analyses, carried out in the 1970s, suggested a strong emphasis on geographical (availability) and financial (ability to pay) aspects. More recently, the literature has focused on less tangible aspects, such as cultural, educational, and socioeconomic issues, incorporating the element of acceptability into the notion of health access. The literature also shows that information provides the starting point for access to health, in association with health empowerment and literacy for health care decision-making. The study concludes that improvements in access to health and the guarantee of equity will not be achieved by initiatives focusing on health care systems alone, but rather will depend on intersectoral actions and social and economic policies aimed at eliminating income and education differences. PMID:22569702

  11. Memory availability and referential access

    PubMed Central

    Johns, Clinton L.; Gordon, Peter C.; Long, Debra L.; Swaab, Tamara Y.

    2013-01-01

    Most theories of coreference specify linguistic factors that modulate antecedent accessibility in memory; however, whether non-linguistic factors also affect coreferential access is unknown. Here we examined the impact of a non-linguistic generation task (letter transposition) on the repeated-name penalty, a processing difficulty observed when coreferential repeated names refer to syntactically prominent (and thus more accessible) antecedents. In Experiment 1, generation improved online (event-related potentials) and offline (recognition memory) accessibility of names in word lists. In Experiment 2, we manipulated generation and syntactic prominence of antecedent names in sentences; both improved online and offline accessibility, but only syntactic prominence elicited a repeated-name penalty. Our results have three important implications: first, the form of a referential expression interacts with an antecedent’s status in the discourse model during coreference; second, availability in memory and referential accessibility are separable; and finally, theories of coreference must better integrate known properties of the human memory system. PMID:24443621

  12. Biomass accessibility analysis using electron tomography

    SciTech Connect

    Hinkle, Jacob D.; Ciesielski, Peter N.; Gruchalla, Kenny; Munch, Kristin R.; Donohoe, Bryon S.

    2015-12-25

    Substrate accessibility to catalysts has been a dominant theme in theories of biomass deconstruction. Furthermore, current methods of quantifying accessibility do not elucidate mechanisms for increased accessibility due to changes in microstructure following pretreatment.

  13. 36 CFR 9.32 - Access.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... CFR 2.17. (d) No access to a site outside a unit will be permitted across unit lands unless such access is by foot, pack animal, or designated road. Persons using designated roads for access to such...

  14. 36 CFR 9.32 - Access.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... CFR 2.17. (d) No access to a site outside a unit will be permitted across unit lands unless such access is by foot, pack animal, or designated road. Persons using designated roads for access to such...

  15. 36 CFR 9.32 - Access.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... CFR 2.17. (d) No access to a site outside a unit will be permitted across unit lands unless such access is by foot, pack animal, or designated road. Persons using designated roads for access to such...

  16. 36 CFR 9.32 - Access.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CFR 2.17. (d) No access to a site outside a unit will be permitted across unit lands unless such access is by foot, pack animal, or designated road. Persons using designated roads for access to such...

  17. Resilient packet ring media access protocol

    NASA Astrophysics Data System (ADS)

    Thepot, Frederic

    2001-07-01

    The discussion will cover the new initiative to create a new MAC layer standard for resilient packet rings: IEEE 802.17 RPR. The key aspects of the presentation will include a preliminary address of the Metro Area Network today and the current networking technologies such as SONET/SDH which are not optimized to carry IP traffic over Metro MAN. The next segment will cover the options which could change the traditional and expensive layered networking model, and address the real benefits of marrying several technologies like Ethernet, SONET/SDH and IP into one technology. The next part of the discussion will detail the technical advantages a new MAC will bring to the services providers. Lastly a summary of the view and strategy about the acceptance and deployment of this new technology in the next 12 months, specifically, now one defines and develops standards for a Resilient Packet Ring Access Protocol for use in Local, Metropolitan, and Wide Area Networks for transfer of data packets at rates scalable to multiple gigabits per second; specifically address the data transmission requirements of carriers that have present and planned fiber optic physical infrastructure in a ring topology; and, defining and developing detailed specifications for using existing and/or new physical layers at appropriate data rates that will support transmission of this access protocol.

  18. Access to care for children with autism in the context of state Medicaid reimbursement.

    PubMed

    Thomas, Kathleen C; Parish, Susan L; Rose, Roderick A; Kilany, Mona

    2012-11-01

    This paper examines the role of state residence and Medicaid reimbursement rates in explaining the relationship between having autism and access to care for children. Three questions are addressed: (1) Is there variation across states in the relationship between having autism and access to care? (2) Does taking account of state residence explain a significant amount of the variation in this relationship? (3) Does accounting for Medicaid reimbursement rates enhance our understanding of this relationship? Data from the 2005 National Survey of Children with Special Health Care Needs were combined with state characteristics to estimate a hierarchical generalized linear model of the association between state residence, Medicaid reimbursement rate and problems accessing care for children with special health care needs with and without autism. Findings indicate there is significant variation between states in the relationship between having autism and problems accessing care, and accounting for state residence explains a significant amount of variation in the model. Medicaid reimbursement rates have an independent effect on access to care for children with autism: when families raising children with autism live in states with higher reimbursement rates, they have lower odds of experiencing problems accessing care. The state context in which families live impacts access to care for children with autism. Moreover, when families live in states with higher Medicaid reimbursement rates, they are less likely to experience problems getting care. The value of this analysis is that it helps identify where to look for strategies to improve access. PMID:21833759

  19. The 'SAFARI' Technique Using Retrograde Access Via Peroneal Artery Access

    SciTech Connect

    Zhuang, Kun Da; Tan, Seck Guan; Tay, Kiang Hiong

    2012-08-15

    The 'SAFARI' technique or subintimal arterial flossing with antegrade-retrograde intervention is a method for recanalisation of chronic total occlusions (CTOs) when subintimal angioplasty fails. Retrograde access is usually obtained via the popliteal, distal anterior tibial artery (ATA)/dorsalis pedis (DP), or distal posterior tibial artery (PTA). Distal access via the peroneal artery has not been described and has a risk of continued bleeding, leading to compartment syndrome due to its deep location. We describe our experience in two patients with retrograde access via the peroneal artery and the use of balloon-assisted hemostasis for these retrograde punctures. This approach may potentially give more options for endovascular interventions in lower limb CTOs.

  20. Three essays on access pricing

    NASA Astrophysics Data System (ADS)

    Sydee, Ahmed Nasim

    In the first essay, a theoretical model is developed to determine the time path of optimal access price in the telecommunications industry. Determining the optimal access price is an important issue in the economics of telecommunications. Setting a high access price discourages potential entrants; a low access price, on the other hand, amounts to confiscation of private property because the infrastructure already built by the incumbent is sunk. Furthermore, a low access price does not give the incumbent incentives to maintain the current network and to invest in new infrastructures. Much of the existing literature on access pricing suffers either from the limitations of a static framework or from the assumption that all costs are avoidable. The telecommunications industry is subject to high stranded costs and, therefore, to address this issue a dynamic model is imperative. This essay presents a dynamic model of one-way access pricing in which the compensation involved in deregulatory taking is formalized and then analyzed. The short run adjustment after deregulatory taking has occurred is carried out and discussed. The long run equilibrium is also analyzed. A time path for the Ramsey price is shown as the correct dynamic price of access. In the second essay, a theoretical model is developed to determine the time path of optimal access price for an infrastructure that is characterized by congestion and lumpy investment. Much of the theoretical literature on access pricing of infrastructure prescribes that the access price be set at the marginal cost of the infrastructure. In proposing this rule of access pricing, the conventional analysis assumes that infrastructure investments are infinitely divisible so that it makes sense to talk about the marginal cost of investment. Often it is the case that investments in infrastructure are lumpy and can only be made in large chunks, and this renders the marginal cost concept meaningless. In this essay, we formalize a model of

  1. Creating Connections: College Innovations in Flexibility, Access and Participation.

    ERIC Educational Resources Information Center

    Further Education Development Agency, London (England).

    This document contains 14 papers explaining how 12 further education colleges in the United Kingdom used fellowship funds to maximize their use of current information and learning technologies and make other substantial innovations to improve their flexibility, accessibility, and rates of participation. The following papers are included: "Leading…

  2. Needs and Beliefs in Construct Accessibility: Keys to New Understanding.

    ERIC Educational Resources Information Center

    Culbertson, Hugh M.; Denbow, Carl J.; Stempel, Guido H., III

    1998-01-01

    Surveyed 390 Ohioans who rated five concepts as to closeness of linkage with osteopathic medicine. Finds, as suggested by the storage-bin concept in construct accessibility theory, that those who had experience with these concepts were most apt to use them in assessing osteopathic medicine--this held even though most respondents reported no…

  3. Economic Inequality and Higher Education: Access, Persistence, and Success

    ERIC Educational Resources Information Center

    Dickert-Conlin, Stacy, Ed.; Rubenstein, Ross, Ed.

    2007-01-01

    The vast disparities in college attendance and graduation rates between students from different class backgrounds is a growing social concern. "Economic Inequality and Higher Education" investigates the connection between income inequality and unequal access to higher education, and proposes solutions that the state and federal governments and…

  4. Freedom of Access to Information: The Right to Privacy

    ERIC Educational Resources Information Center

    Rice, George P.

    1976-01-01

    Discusses accessibility of needed information and maintenance of individual privacy in terms of the 1974 Freedom of Information Act, and explores the implications for educational practices. Vital Speeches of The Day, City News Publishing Company, Box 606, Southold, N.Y. 11971. Subscription Rates: $12.00 a year; $22.20 two years; $.60, single…

  5. The South Carolina Higher Education Access & Equity Program, 2004

    ERIC Educational Resources Information Center

    South Carolina Commission on Higher Education, 2004

    2004-01-01

    The Access and Equity Program vision is to achieve educational equity for all students and faculty in higher education. Success in college should not be affected by a student's race. Minority enrollment should be at least proportional to the minority population in South Carolina and minority graduation rates should be comparable to the graduation…

  6. Opening the Doors of Our Schools: Increasing Access to Technology.

    ERIC Educational Resources Information Center

    Polley, Paula

    Computers are strategic tools in readying students for the future, as well as important learning tools for the present. The use of computers can help alleviate critical problems including low self-esteem, dropout rates, and illiteracy. This guide proposes making school computers accessible to students during times when schools are normally closed:…

  7. 47 CFR 76.975 - Commercial leased access dispute resolution.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Commercial leased access dispute resolution. 76... SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Cable Rate Regulation § 76.975 Commercial leased... commercial channel capacity available in accordance with the provisions of Title VI of the Communications...

  8. A Review of Open Access Self-Archiving Mandate Policies

    ERIC Educational Resources Information Center

    Xia, Jingfeng; Gilchrist, Sarah B.; Smith, Nathaniel X. P.; Kingery, Justin A.; Radecki, Jennifer R.; Wilhelm, Marcia L.; Harrison, Keith C.; Ashby, Michael L.; Mahn, Alyson J.

    2012-01-01

    This article reviews the history of open access (OA) policies and examines the current status of mandate policy implementations. It finds that hundreds of policies have been proposed and adopted at various organizational levels and many of them have shown a positive effect on the rate of repository content accumulation. However, it also detects…

  9. 47 CFR 76.975 - Commercial leased access dispute resolution.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 4 2012-10-01 2012-10-01 false Commercial leased access dispute resolution. 76.975 Section 76.975 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Cable Rate Regulation § 76.975 Commercial...

  10. 47 CFR 76.975 - Commercial leased access dispute resolution.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 4 2013-10-01 2013-10-01 false Commercial leased access dispute resolution. 76.975 Section 76.975 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Cable Rate Regulation § 76.975 Commercial...

  11. 47 CFR 76.975 - Commercial leased access dispute resolution.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 4 2014-10-01 2014-10-01 false Commercial leased access dispute resolution. 76.975 Section 76.975 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Cable Rate Regulation § 76.975 Commercial...

  12. Access, Achievement, Completion, and "Milling Around" in Postsecondary Vocational Education.

    ERIC Educational Resources Information Center

    Grubb, W. Norton

    This study analyzes the results of the increased access of students to postsecondary vocational education, especially in two-year colleges, in terms of completion rates and job placement. Data examined include the following: (1) initial enrollments in higher education; (2) fields of study in postsecondary education; (3) progress through…

  13. Service Accessibility for Lesbian, Gay, Bisexual, Transgender, and Questioning Youth

    ERIC Educational Resources Information Center

    Acevedo-Polakovich, Ignacio David; Bell, Bailey; Gamache, Peter; Christian, Allison S.

    2013-01-01

    Although Lesbian, Gay, Bisexual, Transgender, Queer and/or Questioning (LGBTQ) youth experience alarming rates of behavioral and social problems, service use among these youth is disproportionately low. It is likely that decreased service accessibility plays a causal role in service underutilization among LGBTQ youth. To expand the existing…

  14. Introduction: Access to fertility care.

    PubMed

    Davis, Owen K; Sokol, Rebecca Z

    2016-05-01

    Given that only an estimated 24% of infertile couples in the United States can fully engage in the medical care required to successfully conceive, the American Society for Reproductive Medicine (ASRM) has incorporated improved access to the full gamut of fertility therapies as an integral component of the Society's strategic plan that was launched in 2014. Toward this end, the ASRM hosted a two-day summit held in Washington D.C. in September 2015 that attracted thought leaders, both speakers and attendees, from around the world. This issue's Views and Reviews focuses on several key areas integral to this effort: an appreciation of the economic challenges to access, as well as the impact and interplay of racial, ethnic, emotional and gender-specific issues in the treatment of infertility. The potential to broaden access to care through modification of existing assisted reproductive techniques is also explored. PMID:27054311

  15. Mechanisms that improve referential access.

    PubMed

    Gernsbacher, M A

    1989-07-01

    Two mechanisms, suppression and enhancement, are proposed to improve referential access. Enhancement improves the accessibility of previously mentioned concepts by increasing or boosting their activation; suppression improves concepts' accessibility by decreasing or dampening the activation of other concepts. Presumably, these mechanisms are triggered by the informational content of anaphors. Six experiments investigated this proposal by manipulating whether an anaphoric reference was made with a very explicit, repeated name anaphor or a less explicit pronoun. Subjects read sentences that introduced two participants in their first clauses, for example, "Ann predicted that Pam would lose the track race," and the sentences referred to one of the two participants in their second clauses, "but Pam/she came in first very easily." While subjects read each sentence, the activation level of the two participants was measured by a probe verification task. The first two experiments demonstrated that explicit, repeated name anaphors immediately trigger the enhancement of their own antecedents and immediately trigger the suppression of other (nonantecedent) participants. The third experiment demonstrated that less explicit, pronoun anaphors also trigger the suppression of other nonantecedents, but they do so less quickly--even when, as in the fourth experiment, the semantic information to identify their antecedents occurs prior to the pronouns (e.g., "Ann predicted that Pam would lose the track race. But after winning the race, she..."). The fifth experiment demonstrated that more explicit pronouns--pronouns that match the gender of only one participant-trigger suppression more powerfully. A final experiment demonstrated that it is not only rementioned participants who improve their referential access by triggering the suppression of other participants; newly introduced participants do so too (e.g., "Ann predicted that Pam would lose the track race, but Kim..."). Thus, both

  16. ACCESSING HDF DATA VIA OPENDAP

    NASA Astrophysics Data System (ADS)

    Yang, M.; Lee, H.; Folk, M. J.

    2009-12-01

    HDF is a set of data formats and software libraries for storing scientific data with an emphasis on standards, storage, and I/O efficiency. The HDF-EOS version 2 (HDF-EOS2) profile and library, built on top of HDF version 4 (HDF4), define and implement the standard data format for the NASA Earth Science Data and Information System (ESDIS). Since the launch of Terra in 1999, the EOS Data and Information System (EOSDIS) has produced more than three terabytes of EOS earth science data daily. More than five hundred data products in NASA data centers are stored in HDF4. HDF5 is a newer data format. It has been embraced as an important data format for Earth science, HDF-EOS5, which is built on top of HDF5, is the primary data format for data from the Aura satellite. HDF5 is being used as the data format for data products produced from the National Polar Orbiting Environmental Satellite System (NPOESS). The newer version of netCDF, netCDF-4, is built on top of HDF5. The OPeNDAP Data Access Protocol (DAP) and its related software (servers and clients) have emerged as important components of the earth science data system infrastructure. The OPeNDAP protocol is widely used to remotely access earth science data. Several third-party visualization and analysis tools that can read data from OPeNDAP servers, such as IDV, GrADS, Ferret, NCL, MATLAB, and IDL, are widely used by many earth scientists, researchers, and educators to access HDF earth science data. Ensuring easy access to HDF4, HDF5 and HDF-EOS data via the above tools through OPeNDAP will reduce the time for HDF users to visualize the data in their favorite way and improve their working efficiencies accordingly. In the past two years, under the support of NASA ESDIS and ACCESS projects, The HDF Group implemented the HDF5-OPeNDAP data handler so that some NASA HDF-EOS5 Aura Swath and Grid data can be accessed by widely used visualization and analysis tools such as IDV, GrADS, Ferret, NCL and IDL via OPeNDAP. The HDF

  17. Susceptibility and physiological responses of Jatropha curcas accessions to broad mite infestation.

    PubMed

    Evaristo, Anderson Barbosa; Venzon, Madelaine; Matos, Fábio Santos; de Freitas, Ricardo Galvão; Kuki, Kacilda Naomi; Dias, Luiz Antônio Dos Santos

    2013-08-01

    The broad mite Polyphagotarsonemus latus is a key pest of physic nut (Jatropha curcas L.). The purpose of this study was to identify physic nut accessions that are less susceptible to P. latus, in support of the breeding program of J. curcas. We first evaluated population growth rate and injury symptoms of P. latus on different J. curcas accessions and then carried out physiological analyses on P. latus-infested and uninfested accessions. From the germplasm bank of the Federal University of Viçosa, 15 physic nut accessions with high seed oil content, with different genetic background, were tested. The following traits were evaluated: instantaneous population growth rate of P. latus (r i ), injury symptoms, relative leaf water content, specific leaf area, gas exchange, photosynthetic pigments, nitrogen and biomass of the aerial part. Significant differences were observed for P. latus population growth rate and injury symptoms among accessions. A positive correlation between P. latus growth rate and injury was found. The UFVJC72 accession stood out as the more resistant, considering P. latus growth rate and injury symptoms, compared with most accessions. Physiological responses did not vary among accessions, but did between infested and uninfested plants. In P. latus-infested plants, net photosynthesis was on average 50.5 % lower than in uninfested plants, whereas stomatal conductance and transpiration decreased by 46.2 and 51.6 %, respectively. PMID:23456604

  18. 32 CFR 2400.25 - Access.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... § 2400.25 Access. (a) A person is eligible for access to classified information provided that a... established by the head of each office to prevent access to classified information before a personnel security clearance has been granted. The number of people cleared and granted access to classified information...

  19. 36 CFR 228.12 - Access.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 2 2011-07-01 2011-07-01 false Access. 228.12 Section 228.12... Minerals § 228.12 Access. An operator is entitled to access in connection with operations, but no road... other means of access, including but not limited to off-road vehicles, be used until the operator...

  20. 46 CFR 153.330 - Access.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Access. 153.330 Section 153.330 Shipping COAST GUARD..., LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Pumprooms § 153.330 Access. (a) The access door to a cargo pump-room must open on the weatheredeck. (b) The access way to a...

  1. 48 CFR 252.239-7002 - Access.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Access. 252.239-7002... Clauses 252.239-7002 Access. As prescribed in 239.7411(a), use the following clause: Access (DEC 1991) (a) Subject to military security regulations, the Government shall permit the Contractor access at...

  2. 36 CFR 228.12 - Access.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Access. 228.12 Section 228.12... Minerals § 228.12 Access. An operator is entitled to access in connection with operations, but no road... other means of access, including but not limited to off-road vehicles, be used until the operator...

  3. 10 CFR 2.1007 - Access.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Access. 2.1007 Section 2.1007 Energy NUCLEAR REGULATORY... Geologic Repository § 2.1007 Access. (a)(1) A system to provide electronic access to the Licensing Support...-license application phase. (2) A system to provide electronic access to the Licensing Support...

  4. 43 CFR 36.12 - Temporary access.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... appropriate Federal agency for an access permit by providing the relevant information requested in the SF 299... 43 Public Lands: Interior 1 2011-10-01 2011-10-01 false Temporary access. 36.12 Section 36.12... ACROSS, AND ACCESS INTO, CONSERVATION SYSTEM UNITS IN ALASKA § 36.12 Temporary access. (a) For...

  5. 10 CFR 1017.20 - Routine access.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... INFORMATION Access to Unclassified Controlled Nuclear Information § 1017.20 Routine access. (a) Authorized... 10 Energy 4 2011-01-01 2011-01-01 false Routine access. 1017.20 Section 1017.20 Energy DEPARTMENT... access to the UCNI, subject to limitations in paragraph (b) of this section, and who may...

  6. 32 CFR 2400.25 - Access.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... § 2400.25 Access. (a) A person is eligible for access to classified information provided that a... established by the head of each office to prevent access to classified information before a personnel security clearance has been granted. The number of people cleared and granted access to classified information...

  7. 10 CFR 1017.20 - Routine access.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... INFORMATION Access to Unclassified Controlled Nuclear Information § 1017.20 Routine access. (a) Authorized... 10 Energy 4 2010-01-01 2010-01-01 false Routine access. 1017.20 Section 1017.20 Energy DEPARTMENT... access to the UCNI, subject to limitations in paragraph (b) of this section, and who may...

  8. 46 CFR 153.330 - Access.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Access. 153.330 Section 153.330 Shipping COAST GUARD..., LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Pumprooms § 153.330 Access. (a) The access door to a cargo pump-room must open on the weatheredeck. (b) The access way to a...

  9. 48 CFR 252.239-7002 - Access.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 3 2011-10-01 2011-10-01 false Access. 252.239-7002... Clauses 252.239-7002 Access. As prescribed in 239.7411(a), use the following clause: Access (DEC 1991) (a) Subject to military security regulations, the Government shall permit the Contractor access at...

  10. 43 CFR 36.12 - Temporary access.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... appropriate Federal agency for an access permit by providing the relevant information requested in the SF 299... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Temporary access. 36.12 Section 36.12... ACROSS, AND ACCESS INTO, CONSERVATION SYSTEM UNITS IN ALASKA § 36.12 Temporary access. (a) For...

  11. Educational Access in Bangladesh. Country Policy Brief

    ERIC Educational Resources Information Center

    Ahmed, Manzoor

    2008-01-01

    This Policy Brief describes and explains patterns of access to schooling in Bangladesh. It outlines types of educational provision and provides some basic statistics on access, vulnerability and exclusion, as well as insights into the characteristics of those denied access. It is based on findings from the "Country Analytic Review on Access to…

  12. 46 CFR 153.330 - Access.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Access. 153.330 Section 153.330 Shipping COAST GUARD..., LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Pumprooms § 153.330 Access. (a) The access door to a cargo pump-room must open on the weatheredeck. (b) The access way to a...

  13. 46 CFR 153.330 - Access.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Access. 153.330 Section 153.330 Shipping COAST GUARD..., LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Pumprooms § 153.330 Access. (a) The access door to a cargo pump-room must open on the weatherdeck. (b) The access way to a...

  14. 46 CFR 153.330 - Access.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Access. 153.330 Section 153.330 Shipping COAST GUARD..., LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Pumprooms § 153.330 Access. (a) The access door to a cargo pump-room must open on the weatheredeck. (b) The access way to a...

  15. 47 CFR 76.702 - Public access.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 4 2012-10-01 2012-10-01 false Public access. 76.702 Section 76.702 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Cable Television Access § 76.702 Public access. A cable operator may refuse to transmit any public access program...

  16. Equity for open-access journal publishing.

    PubMed

    Shieber, Stuart M

    2009-08-01

    Open-access journals, which provide access to their scholarly articles freely and without limitations, are at a systematic disadvantage relative to traditional closed-access journal publishing and its subscription-based business model. A simple, cost-effective remedy to this inequity could put open-access publishing on a path to become a sustainable, efficient system. PMID:19652697

  17. Giving Patients Access to Their Medical Records via the Internet

    PubMed Central

    Masys, Daniel; Baker, Dixie; Butros, Amy; Cowles, Kevin E.

    2002-01-01

    Objective: The Patient-Centered Access to Secure Systems Online (pcasso) project is designed to apply state-of-the-art-security to the communication of clinical information over the Internet. Design: The authors report the legal and regulatory issues associated with deploying the system, and results of its use by providers and patients. Human subject protection concerns raised by the Institutional Review Board focused on three areas—unauthorized access to information by persons other than the patient; the effect of startling or poorly understood information; and the effect of patient access to records on the record-keeping behavior of providers. Measurements: Objective and subjective measures of security and usability were obtained. Results: During its initial deployment phase, the project enrolled 216 physicians and 41 patients; of these, 68 physicians and 26 patients used the system one or more times. The system performed as designed, with no unauthorized information access or intrusions detected. Providers rated the usability of the system low because of the complexity of the secure login and other security features and restrictions limiting their access to those patients with whom they had a professional relationship. In contrast, patients rated the usability and functionality of the system favorably. Conclusion: High-assurance systems that serve both patients and providers will need to address differing expectations regarding security and ease of use. PMID:11861633

  18. Accessing General and Sexual Healthcare: Experiences of Urban Youth.

    PubMed

    Miller, Melissa K; Wickliffe, Joi; Jahnke, Sara; Linebarger, Jennifer S; Dowd, Denise

    2014-07-01

    Urban adolescents face many barriers to health care that contribute to health disparities in rates of sexually transmitted infections (STIs) and unintended pregnancy. Designing interventions to increase access to health care is a complex process that requires understanding the perspectives of adolescents. We conducted six focus groups to explore the attitudes and beliefs about general and sexual health care access as well as barriers to care among urban, economically disadvantaged adolescents. Participants first completed a written survey assessing health behaviors, health care utilization, and demographics. The discussion guide was based on the Theory of Planned Behavior and its constructs: attitudes, subjective norms, and perceived behavioral control. Transcripts of group discussions were analyzed using directed content analysis with triangulation and consensus to resolve differences. Fifty youth participated (mean age 15.5 years; 64% female; 90% African American). Many (23%) reported missed health care in the previous year. About half (53%) reported previous sexual intercourse; of these, 35% reported no previous sexual health care. Youth valued adults as important referents for accessing care as well as multiple factors that increased comfort such as good communication skills, and an established relationship. However, many reported mistrust of physicians and identified barriers to accessing care including fear and lack of time. Most felt that accessing sexual health care was more difficult than general care. These findings could inform future interventions to improve access to care and care-seeking behaviors among disadvantaged youth. PMID:25101138

  19. Concurrent access to nicotine and sucrose in rats

    PubMed Central

    Hogarth, Lee; Shoaib, Mohammed

    2014-01-01

    Background Animal models that allow concurrent access to drug and nondrug reinforcers provide unique insight into the etiology, maintenance, and treatment of drug use. Objectives We sought to develop and utilize a concurrent access procedure with nicotine and sucrose in rats. Methods Pressing one lever delivered intravenous nicotine, and pressing another lever delivered sucrose pellets, with both reinforcers freely available throughout daily sessions. Results Rats that had been pretrained with nicotine on some days and sucrose on other days responded on both levers when subsequently given concurrent access, but almost all responded at substantially higher rates on the sucrose lever. In contrast, rats pretrained exclusively with nicotine before being given concurrent access showed individual differences, with about half responding more on the nicotine lever. Treatment with the nicotinic receptor partial agonist varenicline selectively decreased nicotine self-administration. Food restriction and removal of the sucrose lever both increased nicotine self-administration. Conclusions The finding that rats continue to take nicotine when sucrose is concurrently available—and in many cases take it more frequently than sucrose—demonstrates that nicotine self-administration does not only occur in the absence of alternative reinforcement options. As a model of human nicotine use, concurrent access is more naturalistic and has higher face validity than procedures in which only one reinforcer is available or choosing one reinforcer precludes access to other reinforcers. As such, this procedure could be useful for evaluating therapeutic agents and improving our understanding of environmental conditions that promote or discourage nicotine use. PMID:25366874

  20. Enhanced view random access ability for multiview video coding

    NASA Astrophysics Data System (ADS)

    Elmesloul Nasri, Seif Allah; Khelil, Khaled; Doghmane, Noureddine

    2016-03-01

    Apart from the efficient compression, reducing the complexity of the view random access is one of the most important requirements that should be considered in multiview video coding. In order to obtain an efficient compression, both temporal and inter-view correlations are exploited in the multiview video coding schemes, introducing higher complexity in the temporal and view random access. We propose an inter-view prediction structure that aims to lower the cost of randomly accessing any picture at any position and instant, with respect to the multiview reference model JMVM and other recent relevant works. The proposed scheme is mainly based on the use of two base views (I-views) in the structure with selected positions instead of a single reference view as in the standard structures. This will, therefore, provide a direct inter-view prediction for all the remaining views and will ensure a low-delay view random access ability while maintaining a very competitive bit-rate performance with a similar video quality measured in peak signal-to-noise ratio. In addition to a new evaluation method of the random access ability, the obtained results show a significant improvement in the view random accessibility with respect to other reported works.

  1. Remotely Accessible Management System (RAMS).

    ERIC Educational Resources Information Center

    Wood, Rex

    Oakland Schools, an Intermediate School District for Administration, operates a Remotely Accessible Management System (RAMS). RAMS is composed of over 100 computer programs, each of which performs procedures on the files of the 28 local school districts comprising the constituency of Oakland Schools. This regional service agency covers 900 square…

  2. Ballistic representation for kinematic access

    NASA Astrophysics Data System (ADS)

    Alfano, Salvatore

    2011-01-01

    This work uses simple two-body orbital dynamics to initially determine the kinematic access for a ballistic vehicle. Primarily this analysis was developed to assess when a rocket body might conjunct with an orbiting satellite platform. A family of access opportunities can be represented as a volume for a specific rocket relative to its launch platform. Alternately, the opportunities can be represented as a geographical footprint relative to aircraft or satellite position that encompasses all possible launcher locations for a specific rocket. A thrusting rocket is treated as a ballistic vehicle that receives all its energy at launch and follows a coasting trajectory. To do so, the rocket's burnout energy is used to find its equivalent initial velocity for a given launcher's altitude. Three kinematic access solutions are then found that account for spherical Earth rotation. One solution finds the maximum range for an ascent-only trajectory while another solution accommodates a descending trajectory. In addition, the ascent engagement for the descending trajectory is used to depict a rapid access scenario. These preliminary solutions are formulated to address ground-, sea-, or air-launched vehicles.

  3. Gaining Access to the Internet.

    ERIC Educational Resources Information Center

    Notess, Greg R.

    1992-01-01

    Discusses Internet services and protocols (i.e., electronic mail, file transfer, and remote login) and provides instructions for retrieving guides and directories of the Internet. Services providing access to the Internet are described, including bulletin board systems, regional networks, nationwide connections, and library organizations; and a…

  4. LANSCE personnel access control system

    SciTech Connect

    Sturrock, J.C.; Gallegos, F.R.; Hall, M.J.

    1997-01-01

    The Radiation Security System (RSS) at the Los Alamos Neutron Science Center (LANSCE) provides personnel protection from prompt radiation due to accelerated beam. The Personnel Access Control System (PACS) is a component of the RSS that is designed to prevent personnel access to areas where prompt radiation is a hazard. PACS was designed to replace several older personnel safety systems (PSS) with a single modem unified design. Lessons learned from the operation over the last 20 years were incorporated into a redundant sensor, single-point failure safe, fault tolerant, and tamper-resistant system that prevents access to the beam areas by controlling the access keys and beam stoppers. PACS uses a layered philosophy to the physical and electronic design. The most critical assemblies are battery backed up, relay logic circuits; less critical devices use Programmable Logic Controllers (PLCs) for timing functions and communications. Outside reviewers have reviewed the operational safety of the design. The design philosophy, lessons learned, hardware design, software design, operation, and limitations of the device are described.

  5. Access, Intellectual Freedom and Libraries.

    ERIC Educational Resources Information Center

    Darling, Richard L.

    1979-01-01

    Reviews attitudes toward censorship in the United States throughout its history in relation to the nation and its institutions. The library is recognized as an institution in which censorship has no place, due to its creed of information access and intellectual freedom for all. (MBR)

  6. Group Access for Disabled Adults.

    ERIC Educational Resources Information Center

    Dale, Mark; Green, Pat

    1998-01-01

    Evaluation of a project to improve higher education access for adults with disabilities found students preferred separate over integrated provision. In integrated programs they felt isolated by teachers' lack of understanding and other students' reactions. In discrete programs they experienced shared understanding of disability, support, and work…

  7. AccessSTEM: Building Capacity

    ERIC Educational Resources Information Center

    DO-IT, 2009

    2009-01-01

    A series of activities were undertaken to understand the underrepresentation of people with disabilities in science, technology, engineering, and mathematics (STEM) careers and increase their participation in these fields. "AccessSTEM" collaborated with key stakeholders to conduct a "Capacity-Building Institute" ("CBI") in April 2009; share…

  8. Garnet Random-Access Memory

    NASA Technical Reports Server (NTRS)

    Katti, Romney R.

    1995-01-01

    Random-access memory (RAM) devices of proposed type exploit magneto-optical properties of magnetic garnets exhibiting perpendicular anisotropy. Magnetic writing and optical readout used. Provides nonvolatile storage and resists damage by ionizing radiation. Because of basic architecture and pinout requirements, most likely useful as small-capacity memory devices.

  9. Accessible Computers from the Box.

    ERIC Educational Resources Information Center

    Vanderheiden, Gregg C.

    The paper briefly discusses the design of computers to allow their use by the 20% of the American population who have reduced abilities in such areas as manipulation, vision, hearing, and cognition. The role of manufacturers of standard computers in increasing computer accessibility is one of providing computers that can be used by an increasing…

  10. The Inevitability of Open Access

    ERIC Educational Resources Information Center

    Lewis, David W.

    2012-01-01

    Open access (OA) is an alternative business model for the publication of scholarly journals. It makes articles freely available to readers on the Internet and covers the costs associated with publication through means other than subscriptions. This article argues that Gold OA, where all of the articles of a journal are available at the time of…

  11. Multilingual Access for Information Systems.

    ERIC Educational Resources Information Center

    Peters, Carol; Sheridan, Paraic

    With the rapid growth of the global information society, the concept of library has evolved to embrace all kinds of information collections, on all kinds of storage media, and using many different access methods. The users of today's information networks and digital libraries, no longer restricted by geographic or spatial boundaries, want to be…

  12. The Simple Spectral Access protocol

    NASA Astrophysics Data System (ADS)

    Dolensky, Markus; Tody, Doug

    2004-09-01

    The goal of the Simple Spectral Access (SSA) specification is to define a uniform interface to spectral data including spectral energy distributions (SEDs), 1D spectra, and time series data. In contrast to 2D images, spectra are stored in a wide variety of formats and there is no widely used standard in astronomy for representing spectral data, hence part of the challenge of specifying SSA was defining a general spectrophotometric data model as well as definitions of standard serializations in a variety of data formats including XML and FITS. Access is provided to both atlas (pre-computed) data and to virtual data which is computed on demand. The term simple in Simple Spectrum Access refers to the design goal of simplicity in both implementing spectral data services and in retrieving spectroscopic data from distributed data collections. SSA is a product of the data access layer (DAL) working group of the International Virtual Observatory Alliance (IVOA). The requirements were derived from a survey among spectral data providers and data consumers and were further refined in a broad discussion in meetings and electronic forums as well as by prototyping efforts within the European Astrophysical Virtual Observatory (AVO) and the US National Virtual Observatory (NVO).

  13. Arts Accessibility for the Deaf.

    ERIC Educational Resources Information Center

    Bergman, Eugene

    The booklet provides information and resources for cultural organizations and institutions interested in making the arts accessible to deaf citizens. Preliminary information includes a discussion of deafness in America and the deaf in the history of the arts and notes that the era of silent films was the golden age of cinema. Listed are 36…

  14. Plated wire random access memories

    NASA Technical Reports Server (NTRS)

    Gouldin, L. D.

    1975-01-01

    A program was conducted to construct 4096-work by 18-bit random access, NDRO-plated wire memory units. The memory units were subjected to comprehensive functional and environmental tests at the end-item level to verify comformance with the specified requirements. A technical description of the unit is given, along with acceptance test data sheets.

  15. Accessing Students' Reasoning for Disengagement

    ERIC Educational Resources Information Center

    Deed, Craig

    2011-01-01

    This paper examines what students can tell us about their strategic decision to engage or disengage from learning. A means of accessing student knowledge and experience about teaching and learning is explicated, along with a discussion of student reasoning for making an investment in learning. It is argued that disengagement is a reasoned decision…

  16. Town + Gown + CATV = Community Access.

    ERIC Educational Resources Information Center

    Clemens, Donald J.

    1980-01-01

    Describes a cooperative venture between Paducah Community College, Comcast Cable, and Paducah, Kentucky, and the roles each of these organizations played in establishing a public access channel which would provide informational and general interest programs, as well as college courses. Offers information on programing, financial support, and…

  17. Accessibility: Maximum Mobility and Function.

    ERIC Educational Resources Information Center

    Smyser, Michael

    2003-01-01

    Describes how to design school and university labs to comply with Americans with Disabilities Act (ADA) standards, focusing on counter height for students in wheelchairs; appropriate knee space and sink height in sink areas; ADA-compliant fume hoods; accessible laboratory doors and entryways; and safety concerns (e.g., emergency eyewash stations…

  18. Accessing ITP: Accommodating the Disabled.

    ERIC Educational Resources Information Center

    Stewart, R. Wayne

    The Information Technology Project (ITP) at Clayton College & State University (CCSU) (Georgia) focuses on information technology as a central part of teaching and learning, primarily through Universal Personal Information Technology Access (UPITA). UPITA equips each student and faculty member with a powerful multimedia notebook computer with…

  19. Academic Access and New Learning

    ERIC Educational Resources Information Center

    Mandell, Alan; Herman, Lee

    2008-01-01

    Over the past 30+ years, many colleges have made themselves more accessible for adult students. These innovations include flexible scheduling, online learning, professionally-oriented degrees, and credit for what students already know. However, there is more work to be done, particularly in the areas of financial aid for the very large number of…

  20. RAPID ACCESS INFORMATION SYSTEM (RAINS)

    EPA Science Inventory

    RAINS has been designed to provide you fast, easy, flexible access to the Region's vast stores of environmental, programmatic, and administrative data and information. RAINS will allow users to approach and interact with this information in an integrated, multi-dimensional contex...

  1. Postoperative assessment of vascular access.

    PubMed

    Malovrh, Marko

    2014-01-01

    Vascular access problems lead to increased patient morbidity and mortality. Autologous arteriovenous fistulas (AVFs) are preferred over grafts. An increase in utilization of AVFs results in an increased incidence of early AVF failure and nonmaturation. A thorough evaluation of a new AVF after 4-6 weeks after creation should be considered mandatory. Experienced persons can examine AVF and predict its utility as a dialysis access. Detailed physical examination of the access performed by educated and trained staff can provide, in most cases, adequate information about the main causes for AVF dysfunction in case of nonmaturation or in case of late access complications. Physical examination has been shown to be very accurate in assessing fistula and is not difficult to learn. Doppler ultrasound (DU) is an additional diagnostic method to predict the ultimate maturation of newly created AVFs and is also very useful in further defining problems that have been detected by physical examination. DU also provides additional information that is of the utmost importance for the surgical or interventional treatment.In this review, basic principles of physical examination and of DU examination of early and late AVF/graft complications are shown. PMID:24817448

  2. Card Access Know-How.

    ERIC Educational Resources Information Center

    College Planning & Management, 2000

    2000-01-01

    Provides tips for expanding a school's card access system and making it more productive for all concerned. Tips include the use of electronic locks for better security; the need for state-of-the-art card reader system to save money in the long run; selecting vendors to one that manufactures, installs, and supports the card system; and having…

  3. Proximity Displays for Access Control

    ERIC Educational Resources Information Center

    Vaniea, Kami

    2012-01-01

    Managing access to shared digital information, such as photographs and documents. is difficult for end users who are accumulating an increasingly large and diverse collection of data that they want to share with others. Current policy-management solutions require a user to proactively seek out and open a separate policy-management interface when…

  4. Facilitating Physician Access to Medical Reference Information

    PubMed Central

    Bellman, Philip; Havens, Carol; Bertolucci, Ysabel; Streeter, Beth

    2005-01-01

    Context: Computer-based medical reference information is augmenting—and in some cases, replacing—many traditional sources. For Kaiser Permanente (KP) physicians, this change presents both advantages and obstacles to finding medical reference information. Objective: To improve understanding of physician information-seeking behavior and the barriers that limit use of both print-based and computer-based medical reference resources. Design: During 2002 and 2003, two quality-improvement surveys were distributed to full-time KP physicians. Survey instruments sent by conventional mail and by e-mail were based on results of telephone interviews and focus groups, and were designed to be concise and easy to use. Participant response rates exceeded 83%. Outcomes Measures: The surveys examined physician use of online medical reference information, medical libraries and services, self-directed learning resources, and continuing medical education (CME). Results: Of the physicians who responded to the survey, 89% used online resources frequently to enhance care, to inform clinical decisions, to update knowledge, to educate patients, or for a combination of these purposes. Compared with responses from older physicians, responses from younger physicians showed a greater proclivity for using nearly all types of online information. Most physicians obtained CME credits primarily through in-person education programs; few physicians used self-directed electronic learning tools. Obstacles to effective access to information included lack of time, overly complex access methods, and lack of awareness about available resources. Conclusions: A considerable gap exists between physicians' need for information and the resources currently available for delivering this information. Although we observed a clear shift from using printed medical references to using computer-based resources, many barriers prevent their effective use. Clinicians need easy-to-use, seamless systems of medical

  5. Accessibility of antiretroviral therapy in Ghana: convenience of access.

    PubMed

    Addo-Atuah, Joyce; Gourley, Dick; Gourley, Greta; White-Means, Shelley I; Womeodu, Robin J; Faris, Richard J; Addo, Nii Akwei

    2012-01-01

    The convenience of accessing antiretroviral therapy (ART) is important for initial access to care and subsequent adherence to ART. We conducted a qualitative study of people living with HIV/AIDS (PLWHA) and ART healthcare providers in Ghana in 2005. The objective of this study was to explore the participants' perceived convenience of accessing ART by PLWHA in Ghana. The convenience of accessing ART was evaluated from the reported travel and waiting times to receive care, the availability, or otherwise, of special considerations, with respect to the waiting time to receive care, for those PLWHA who were in active employment in the formal sector, the frequency of clinic visits before and after initiating ART, and whether the PLWHA saw the same or different providers at each clinic visit (continuity of care). This qualitative study used in-depth interviews based on Yin's case-study research design to collect data from 20 PLWHA and 24 ART healthcare providers as study participants. • Reported travel time to receive ART services ranged from 2 to 12 h for 30% of the PLWHA. • Waiting time to receive care was from 4 to 9 h. • While known government workers, such as teachers, were attended to earlier in some of the centres, this was not a consistent practice in all the four ART centres studied. • The PLWHA corroborated the providers' description of the procedure for initiating and monitoring ART in Ghana. • PLWHA did not see the same provider every time, but they were assured that this did not compromise the continuity of their care. Our study suggests that convenience of accessing ART is important to both PLWHA and ART healthcare providers, but the participants alluded to other factors, including open provider-patient communication, which might explain the PLWHA's understanding of the constraints under which they were receiving care. The current nation-wide coverage of the ART programme in Ghana, however, calls for the replication of this study to identify

  6. Automated Computer Access Request System

    NASA Technical Reports Server (NTRS)

    Snook, Bryan E.

    2010-01-01

    The Automated Computer Access Request (AutoCAR) system is a Web-based account provisioning application that replaces the time-consuming paper-based computer-access request process at Johnson Space Center (JSC). Auto- CAR combines rules-based and role-based functionality in one application to provide a centralized system that is easily and widely accessible. The system features a work-flow engine that facilitates request routing, a user registration directory containing contact information and user metadata, an access request submission and tracking process, and a system administrator account management component. This provides full, end-to-end disposition approval chain accountability from the moment a request is submitted. By blending both rules-based and rolebased functionality, AutoCAR has the flexibility to route requests based on a user s nationality, JSC affiliation status, and other export-control requirements, while ensuring a user s request is addressed by either a primary or backup approver. All user accounts that are tracked in AutoCAR are recorded and mapped to the native operating system schema on the target platform where user accounts reside. This allows for future extensibility for supporting creation, deletion, and account management directly on the target platforms by way of AutoCAR. The system s directory-based lookup and day-today change analysis of directory information determines personnel moves, deletions, and additions, and automatically notifies a user via e-mail to revalidate his/her account access as a result of such changes. AutoCAR is a Microsoft classic active server page (ASP) application hosted on a Microsoft Internet Information Server (IIS).

  7. Selective access and editing in a database

    NASA Technical Reports Server (NTRS)

    Maluf, David A. (Inventor); Gawdiak, Yuri O. (Inventor)

    2010-01-01

    Method and system for providing selective access to different portions of a database by different subgroups of database users. Where N users are involved, up to 2.sup.N-1 distinguishable access subgroups in a group space can be formed, where no two access subgroups have the same members. Two or more members of a given access subgroup can edit, substantially simultaneously, a document accessible to each member.

  8. Assessing standards of vascular access device care.

    PubMed

    McGuire, Rose

    Vascular access devices (VADs) are essential in health care as they provide vital access for treatment including the infusion of medication, fluids, blood products and nutritional supplements. However, their invasive nature predisposes patients to potential complications, primarily bloodstream infections. This article examines the current standards of VAD care and assesses compliance with current guidelines (national and trust policy) in one hospital setting utilising a practice audit. The audit was conducted in a 500-bed district general hospital over 6 non-consecutive week days. The medical division where the audit took place had 13 wards with 288 beds. A total of 120 VADs were audited, averaging n=9.2 per ward (with a range of 4-18 on each ward). The results demonstrated a collective non-compliance rate of 48%. Although overall compliance was 52%, a poor standard of care was highlighted across the division for all components of the care elements. The post-insertion care of VADs is an essential component of a comprehensive strategy to prevent complications. Consequently, initiatives such as audit, education and feedback should be used in an effort to improve practice and maintain optimal care. PMID:25904534

  9. Feasibility of public access to defibrillation.

    PubMed

    Caffrey, Sherry

    2002-06-01

    Immediate defibrillation is the single most effective therapy to reverse ventricular fibrillation cardiac arrest today. The once physician-only skill of defibrillation has entered mainstream society and is saving the lives of many sudden cardiac arrest (SCA) victims in a variety of settings. The automated external defibrillator (AED) and the concept of public access defibrillation (PAD) are a result of collaborative efforts between the American Heart Association (AHA) and medical manufacturers. Today, airports, airlines, casinos, cruise ships, and other public venues have modernized their first aid kits to include an AED. The success of these programs has ignited a trend in public safety and subsequently marketed the worth of AEDs in the home. Although optimal placement of AEDs remains uncertain, PAD is showing great promise in reducing the death rate from SCA. The lay public, both trained and untrained, is emerging as the next level of emergency care responders able to use a defibrillator. PMID:12386497

  10. Emergency intravenous access through the femoral vein.

    PubMed

    Swanson, R S; Uhlig, P N; Gross, P L; McCabe, C J

    1984-04-01

    A study was undertaken to assess the efficacy and safety of femoral venous catheterization for resuscitation of critically ill patients in the emergency department setting. From May 1982 to April 1983, 100 attempts were made at percutaneous insertion of a large-bore catheter into the femoral veins of patients presenting to our emergency department in cardiac arrest or requiring rapid fluid resuscitation. Eighty-nine attempts were successful. Insertion was generally considered easy, and flow rates were excellent. The only noted complications were four arterial punctures and one minor groin hematoma. This study suggests that short-term percutaneous catheterization of the femoral vein provides rapid, safe, and effective intravenous access. PMID:6703430

  11. Open access chemical probes for epigenetic targets

    PubMed Central

    Brown, Peter J; Müller, Susanne

    2015-01-01

    Background High attrition rates in drug discovery call for new approaches to improve target validation. Academia is filling gaps, but often lacks the experience and resources of the pharmaceutical industry resulting in poorly characterized tool compounds. Discussion The SGC has established an open access chemical probe consortium, currently encompassing ten pharmaceutical companies. One of its mandates is to create well-characterized inhibitors (chemical probes) for epigenetic targets to enable new biology and target validation for drug development. Conclusion Epigenetic probe compounds have proven to be very valuable and have not only spurred a plethora of novel biological findings, but also provided starting points for clinical trials. These probes have proven to be critical complementation to traditional genetic targeting strategies and provided sometimes surprising results. PMID:26397018

  12. 10 CFR Appendix A to Part 25 - Fees for NRC Access Authorization

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Fees for NRC Access Authorization A Appendix A to Part 25 Energy NUCLEAR REGULATORY COMMISSION ACCESS AUTHORIZATION Pt. 25, App. A Appendix A to Part 25—Fees for... of the current OPM billing rate charged for an investigation of type *** Plus the NRC'sprocessing...

  13. Economic Impact of the Critical Access Hospital Program on Kentucky's Communities

    ERIC Educational Resources Information Center

    Ona, Lucia; Davis, Alison

    2011-01-01

    Context: In 1997, the Medicare Rural Hospital Flexibility Grant Program created the Critical Access Hospital (CAH) Program as a response to the financial distress of rural hospitals. It was believed that this program would reduce the rate of rural hospital closures and improve access to health care services in rural communities. Objective: The…

  14. Access and Funding in Public Higher Education--The 2011 National Survey

    ERIC Educational Resources Information Center

    Katsinas, Stephen G.; D'Amico, Mark M.; Friedel, Janice N.

    2011-01-01

    With current tuition increases at more than double the rate of inflation and cuts in state funding and Pell Grant programs, students and their families are being squeezed financially. The purpose of this study was to uncover access and funding issues by displaying current year and future year predictions for all access sectors including community…

  15. Mechanisms that improve referential access*

    PubMed Central

    Gernsbacher, Morton Ann

    2015-01-01

    Two mechanisms, suppression and enhancement, are proposed to improve referential access. Enhancement improves the accessibility of previously mentioned concepts by increasing or boosting their activation; suppression improves concepts’ accessibility by decreasing or dampening the activation of other concepts. Presumably, these mechanisms are triggered by the informational content of anaphors. Six experiments investigated this proposal by manipulating whether an anaphoric reference was made with a very explicit, repeated name anaphor or a less explicit pronoun. Subjects read sentences that introduced two participants in their first clauses, for example, “Ann predicted that Pam would lose the track race,” and the sentences referred to one of the two participants in their second clauses, “but Pam/she came in first very easily.” While subjects read each sentence, the activation level of the two participants was measured by a probe verification task. The first two experiments demonstrated that explicit, repeated name anaphors immediately trigger the enhancement of their own antecedents and immediately trigger the suppression of other (nonantecedent) participants. The third experiment demonstrated that less explicit, pronoun anaphors also trigger the suppression of other nonantecedents, but they do so less quickly—even when, as in the fourth experiment, the semantic information to identify their antecedents occurs prior to the pronouns (e.g., “Ann predicted that Pam would lose the track race. But after winning the race, she …”). The fifth experiment demonstrated that more explicit pronouns – pronouns that match the gender of only one participant—trigger suppression more powerfully. A final experiment demonstrated that it is not only rementioned participants who improve their referential access by triggering the suppression of other participants; newly introduced participants do so too (e.g., “Ann predicted that Pam would lose the track race, but

  16. 45 CFR 156.255 - Rating variations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Welfare Department of Health and Human Services REQUIREMENTS RELATING TO HEALTH CARE ACCESS HEALTH INSURANCE ISSUER STANDARDS UNDER THE AFFORDABLE CARE ACT, INCLUDING STANDARDS RELATED TO EXCHANGES Qualified... section 2701(a)(2) of the PHS Act. (b) Same premium rates. A QHP issuer must charge the same premium...

  17. 45 CFR 156.255 - Rating variations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES REQUIREMENTS RELATING TO HEALTH CARE ACCESS HEALTH INSURANCE ISSUER STANDARDS UNDER THE AFFORDABLE CARE ACT, INCLUDING STANDARDS RELATED TO EXCHANGES Qualified... section 2701(a)(2) of the PHS Act. (b) Same premium rates. A QHP issuer must charge the same premium...

  18. 45 CFR 156.255 - Rating variations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 45 Public Welfare 1 2012-10-01 2012-10-01 false Rating variations. 156.255 Section 156.255 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES REQUIREMENTS RELATING TO HEALTH CARE ACCESS HEALTH INSURANCE ISSUER STANDARDS UNDER THE AFFORDABLE CARE ACT, INCLUDING STANDARDS RELATED TO EXCHANGES Qualified Health Plan Minimum...

  19. 47 CFR 69.108 - Transport rate benchmark.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 3 2012-10-01 2012-10-01 false Transport rate benchmark. 69.108 Section 69.108... Computation of Charges § 69.108 Transport rate benchmark. (a) For transport charges computed in accordance... interoffice transmission using the telephone company's DS1 special access rates. (b) Initial transport...

  20. 47 CFR 69.108 - Transport rate benchmark.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 3 2013-10-01 2013-10-01 false Transport rate benchmark. 69.108 Section 69.108... Computation of Charges § 69.108 Transport rate benchmark. (a) For transport charges computed in accordance... interoffice transmission using the telephone company's DS1 special access rates. (b) Initial transport...