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Sample records for equilibrium dialysis experiments

  1. Equilibrium Dialysis

    African Journals Online (AJOL)

    context of antimicrobial therapy in malnutrition. Dialysis has in the past presented technical problems, being complicated and time-consuming. A new dialysis system based on the equilibrium technique has now become available, and it is the principles and practical application of this apparatus (Kontron Diapack; Kontron.

  2. Protein binding studies with radiolabeled compounds containing radiochemical impurities. Equilibrium dialysis versus dialysis rate determination

    DEFF Research Database (Denmark)

    Honoré, B

    1987-01-01

    The influence of radiochemical impurities in dialysis experiments with high-affinity ligands is investigated. Albumin binding of labeled decanoate (97% pure) is studied by two dialysis techniques. It is shown that equilibrium dialysis is very sensitive to the presence of impurities resulting...

  3. A Printed Equilibrium Dialysis Device with Integrated Membranes for Improved Binding Affinity Measurements.

    Science.gov (United States)

    Pinger, Cody W; Heller, Andrew A; Spence, Dana M

    2017-07-18

    Equilibrium dialysis is a simple and effective technique used for investigating the binding of small molecules and ions to proteins. A three-dimensional (3D) printer was used to create a device capable of measuring binding constants between a protein and a small ion based on equilibrium dialysis. Specifically, the technology described here enables the user to customize an equilibrium dialysis device to fit their own experiments by choosing membranes of various material and molecular-weight cutoff values. The device has dimensions similar to that of a standard 96-well plate, thus being amenable to automated sample handlers and multichannel pipettes. The device consists of a printed base that hosts multiple windows containing a porous regenerated-cellulose membrane with a molecular-weight cutoff of ∼3500 Da. A key step in the fabrication process is a print-pause-print approach for integrating membranes directly into the windows subsequently inserted into the base. The integrated membranes display no leaking upon placement into the base. After characterizing the system's requirements for reaching equilibrium, the device was used to successfully measure an equilibrium dissociation constant for Zn 2+ and human serum albumin (K d = (5.62 ± 0.93) × 10 -7 M) under physiological conditions that is statistically equal to the constants reported in the literature.

  4. Being-in-dialysis: The experience of the machine-body for home dialysis users.

    Science.gov (United States)

    Shaw, Rhonda

    2015-05-01

    New Zealand leads the world in rates of home dialysis use, yet little is known about the experience of home dialysis from the patient's perspective. This article contributes to the literature on the self-care of dialysis patients by examining the relevance of the concept of the machine-body and cyborg embodiment for the lived experience of people with end-stage renal failure. The article, which presents a discussion of 24 in-depth interviews undertaken between 2009 and 2012, shows that although dialysis therapy is disruptive of being and time, study participants experience home dialysis in terms of flexibility, control and independence. While they do not use the term machine-body as a descriptor, the concept resonates with felt experience. Data also indicate that positive experience of home dialysis is relative to socio-economic positioning and the lived relation of patients to others, necessitating further research to examine these factors. © The Author(s) 2014.

  5. Children's experiences of dialysis: a systematic review of qualitative studies

    NARCIS (Netherlands)

    Tjaden, Lidwien; Tong, Allison; Henning, Paul; Groothoff, Jaap; Craig, Jonathan C.

    2012-01-01

    Objective To describe the experiences and perspectives of children and adolescents on dialysis. Design A systematic review of qualitative studies was conducted that explored the experiences of children on dialysis. Electronic databases and reference lists of relevant articles were searched to

  6. Targeted separation of antibacterial peptide from protein hydrolysate of anchovy cooking wastewater by equilibrium dialysis.

    Science.gov (United States)

    Tang, Wenting; Zhang, Hui; Wang, Li; Qian, Haifeng; Qi, Xiguang

    2015-02-01

    Anchovy (Engraulis japonicus) cooking wastewater (ACWW) is a by-product resulted from the production of boiled-dried anchovies in the seafood processing industry. In this study, the protein hydrolysate of ACWW (ACWWPH) was found to have antimicrobial activity after enzymatic hydrolysis with Protamex. For the targeted screening of antibacterial peptides, liposomes constructed from Staphylococcus aureus membrane lipids were used in an equilibrium dialysis system. The hydrolysate was further purified by liposome equilibrium dialysis combined with high performance liquid chromatography. The purified antimicrobial peptide (ACWWP1) was determined to be GLSRLFTALK, with a molecular weight of 1104.6622Da. The peptide exhibited no haemolytic activity up to a concentration of 512μg/ml. It displayed a dose-dependent bactericidal effect in reconstituted milk. The change in cell surface hydrophobicity and membrane-permeable action of the purified ACWWP1 may have contributed to the antibacterial effect. This study suggests that liposome equilibrium dialysis can be used for the targeted screening of antimicrobial peptides. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Distribution coefficients for radionuclides in aquatic environments. Volume 2. Dialysis experiments in marine environments

    International Nuclear Information System (INIS)

    Sibley, T.H.; Nevissi, A.E.; Schell, W.R.

    1981-05-01

    The overall objective of this research program was to obtain new information that can be used to predict the fate of radionuclides that may enter the aquatic environment from nuclear power plants, waste storage facilities or fuel reprocessing plants. Important parameters for determining fate are the distribution of radionuclides between the soluble and particulate phases and the partitioning of radionuclides among various suspended particulates. This report presents the results of dialysis experiments that were used to study the distribution of radionuclides among suspended sediments, phytoplankton, organic detritus, and filtered sea water. Three experiments were conducted to investigate the adsorption kinetics and equilibrium distribution of (59)Fe, (60)Co, (65)Zn, (106)Ru, (137)Cs, (207)Bi, (238)Pu, and (241)Am in marine system. Diffusion across the dialysis membranes depends upon the physico-chemical form of the radionuclides, proceeding quite rapidly for ionic species of (137)Cs and (60)Co but much more slowly for radionuclides which occur primarily as colloids and solid precipitates such as (59)Fe, (207)Bi, and (241)Am. All the radionuclides adsorb to suspended particulates although the amount of adsorption depends upon the specific types and concentration of particulates in the system and the selected radionuclide. High affinity of some radionuclides - e.g., (106)Ru and (241)Am - for detritus and phytoplankton suggests that suspended organics may significantly affect the eventual fate of those radionuclides in marine ecosystems

  8. Equilibrium of the kink source experiment

    International Nuclear Information System (INIS)

    Marklin, G.

    1985-01-01

    The kink source experiment (KSX) was conceived of as a method of injecting helicity into a spheromak making special use of the m = 1 helical Taylor state. It has a Z pinch as a helicity generating source, connected to a flux conserver through an entrance region. Since the entrance region is a long (length > diameter) cyclinder, the magnetic field should be close to the helical Taylor state, which is the minimum energy configuration of a magnetized plasma in an infinite cylinder with no net flux. This paper will be concerned with modeling the actual fields in the entrance region of the KSX using zero-beta ideal MHD equilibrium theory

  9. Equilibrium dialysis-ligand exchange: adaptation of the method for determination of conditional stability constants of radionuclide-fulvic acid complexes

    International Nuclear Information System (INIS)

    Glaus, M.A.; Hummel, W.; Van Loon, L.R.

    1995-01-01

    The equilibrium dialysis-ligand exchange technique (EDLE) is used to determine conditional stability constants for the complexation of metal ions with humic acid, particularly in high pH solutions. Here, this technique has been adapted to measure conditional stability constants with fulvic acid. Fulvic acid permeates across all membranes during the experiment. The quantities involved therefore have to be determined analytically and taken into account when calculating the conditional stability constants. Co(II) and Laurentian Soil fulvic (LFA) acid were selected as a test system in order to investigate the time scale required to establish chemical and diffusion equilibria. After an incubation time of approximately two days, the conditional stability constants measured for the formation of Co-LFA-complexes are not time dependent, although across the whole time period investigated, LFA was still diffusing in increasing amounts across the dialysis membrane. This work demonstrates that the modified EDLE technique can be used in the determination of conditional metal stability constants of fulvic acid. (authors)

  10. Phase Equilibrium, Chemical Equilibrium, and a Test of the Third Law: Experiments for Physical Chemistry.

    Science.gov (United States)

    Dannhauser, Walter

    1980-01-01

    Described is an experiment designed to provide an experimental basis for a unifying point of view (utilizing theoretical framework and chemistry laboratory experiments) for physical chemistry students. Three experiments are described: phase equilibrium, chemical equilibrium, and a test of the third law of thermodynamics. (Author/DS)

  11. "Secrets" of High Pressure Phase Equilibrium Experiment.

    Czech Academy of Sciences Publication Activity Database

    Wichterle, Ivan

    2005-01-01

    Roč. 54, č. 11 (2005), s. 477-479 ISSN 0022-9830 Institutional research plan: CEZ:AV0Z40720504 Keywords : vapour-liquid equilibrium * experimental work Subject RIV: CF - Physical ; Theoretical Chemistry

  12. Peritoneal dialysis in an ageing population: a 10-year experience.

    LENUS (Irish Health Repository)

    Smyth, Andrew

    2012-02-01

    Chronic kidney disease (CKD) is becoming increasingly prevalent and there are increasing numbers of older patients with advanced CKD. Peritoneal dialysis (PD) is a potential treatment. This study aims to compare PD outcomes in age-defined populations in the largest PD centre in the Republic of Ireland over 10 years.

  13. Educational strategies and challenges in peritoneal dialysis: a qualitative study of renal nurses' experiences.

    Science.gov (United States)

    Bergjan, Manuela; Schaepe, Christiane

    2016-06-01

    The aim of the study was to explore renal nurses' experiences, strategies and challenges with regard to the patient education process in peritoneal dialysis. Patient education in peritoneal dialysis is essential to developing a successful home-based peritoneal dialysis program. In this area research is scarce and there is a particular lack of focus on the perspective of the renal nurse. Qualitative design formed by thematic qualitative text analysis. Five group interviews (n = 20) were used to explore the challenges peritoneal dialysis nurses face and the training strategies they use. The interviews were analyzed with thematic qualitative content analysis using deductive and inductive subcategory application. The findings revealed the education barriers perceived by nurses that patients may face. They also showed that using assessment tools is important in peritoneal dialysis patient education, as is developing strategies to promote patient self-management. There is a need for a deeper understanding of affective learning objectives, and existing teaching activities and materials should be revised to incorporate the patient's perspective. Patients usually begin having questions about peritoneal dialysis when they return home and are described as feeling overwhelmed. Adapting existing conditions is considered a major challenge for patients and nurses. The results provided useful insights into the best approaches to educating peritoneal dialysis patients and served to raise awareness of challenges experienced by renal nurses. Findings underline the need for nosogogy - an approach of teaching adults (andragogy) with a chronic disease. Flexibility and cooperation are competencies that renal nurses must possess. Still psychomotor skills dominate peritoneal dialysis patient training, there is a need of both a deeper understanding of affective learning objectives and the accurate use of (self-)assessment tools, particularly for health literacy. © 2016 John Wiley & Sons

  14. Pediatric Reference Intervals for Free Thyroxine and Free Triiodothyronine by Equilibrium Dialysis-Liquid Chromatography-Tandem Mass Spectrometry.

    Science.gov (United States)

    La'ulu, Sonia L; Rasmussen, Kyle J; Straseski, Joely A

    2016-03-05

    Thyroid hormone concentrations fluctuate during growth and development. To accurately diagnose thyroid disease in pediatric patients, reference intervals (RIs) should be established with appropriate age groups from an adequate number of healthy subjects using the most exact methods possible. Obtaining statistically useful numbers of healthy patients is particularly challenging for pediatric populations. The objective of this study was to determine non-parametric RIs for free thyroxine (fT4) and free triiodothyronine (fT3) using equilibrium dialysis-high performance liquid chromatography-tandem mass spectrometry with over 2200 healthy children 6 months-17 years of age. Subjects were negative for both thyroglobulin and thyroid peroxidase autoantibodies and had normal thyrotropin concentrations. The study included 2213 children (1129 boys and 1084 girls), with at least 120 subjects (average of 125) from each year of life, except for the 6 month to 1 year age group (n=96). Non-parametric RIs (95th percentile) for fT4 were: 18.0-34.7 pmol/L (boys and girls, 6 months-6 years) and 14.2-25.7 pmol/L (boys and girls, 7-17 years). RIs for fT3 were: 5.8-13.1 pmol/L (girls, 6 months-6 years); 5.7-11.8 pmol/L (boys, 6 months-6 years); 5.7-10.0 pmol/L (boys and girls, 7-12 years); 4.5-8.6 pmol/L (girls, 13-17 years); and 5.2-9.4 pmol/L (boys, 13-17 years). Numerous significant differences were observed between pediatric age groups and previously established adult ranges. This emphasizes the need for well-characterized RIs for thyroid hormones in the pediatric population.

  15. Experience of peritoneal dialysis in renal failure in children

    International Nuclear Information System (INIS)

    Faraz, A.; Farhan, M.A.; Shaikh, K.; Ali, S.

    2017-01-01

    Objective: To determine the course and efficacy of peritoneal dialysis in children presenting with renal failure. Study Design: Quasi experimental study. Place and Duration of Study: The study was conducted at the Nephrology department of Children's Hospital and Institute of Child Health Lahore from Feb 2007 to Feb 2008. Material and Methods: Forty children diagnosed with renal failure at the Nephrology department of Children's Hospital and Institute of Child Health, Lahore were evaluated for the efficacy of PD, duration of PD and the associated complications. Results: There were 55% cases of acute renal failure and 45% cases of chronic renal failure. The mean duration of PD was 3.8 days. About 75% of all the patients improved with PD. The mortality rate was 22.5%. Leading complications were Catheter-related (leakage/blockade) and peritonitis. Conclusion: We concluded that peritoneal dialysis is lifesaving procedure which improves the acute metabolic derangements of renal failure in children. It is associated with certain complications but the benefits outweigh the complications. (author)

  16. Feedback stabilization experiments using l = 2 equilibrium windings in Scyllac

    International Nuclear Information System (INIS)

    Bartsch, R.R.; Cantrell, E.L.; Gribble, R.F.; Freese, K.B.; Handy, L.E.; Kristal, R.; Miller, G.; Quinn, W.E.

    1977-01-01

    The confinement time in the Scyllac Sector Feedback Experiment has been extended with a pre-programmed equilibrium compensation force. This force was produced by driving a current with a flexible waveform in an additional set of l = 2 windings

  17. Nationwide peritoneal dialysis nurse training in Thailand: 3-year experience.

    Science.gov (United States)

    Thaiyuenwong, Jutiporn; Mahatanan, Nanta; Jiravaranun, Somsong; Boonyakarn, Achara; Rodpai, Somrak; Eiam-Ong, Somchai; Tungsanga, Kriang; Dhanakijcharoen, Prateep; Kanjanabuch, Talerngsak

    2011-09-01

    Peritoneal dialysis (PD) center is not possible to operate if there is no availability of dedicated PD nurse. Generally, the nurse has to play many roles, including educator coordinator, and sometimes leader. As professionalism, the PD nurses need to have both theoretical and practical skills. With the tremendous leap of PD population after the launch of "PD First" policy in Thailand, the shortage of skillful PD nurse is concerned. Hence, the nationwide PD nurse training course was established with the collaborations of many organizations and institutes. Until now, 3 generations of 225 PD nurses are the productions of the course. This number represents 80 percent of PD nurses distributed throughout the whole nation. The survey operated in the year 2010 demonstrated that the output of the course was acceptable in terms of quality since most of the trained PD nurses had a confidence in taking care of PD patients. The quality of patient care is good as indicated by KPIs.

  18. Peritoneal dialysis and peritonitis rate: Kuwait, four years' experience.

    Science.gov (United States)

    Alyousef, Anas M; Abdou, Salah M; Mansour, Yasser S; Radi, Ahmad D

    2016-01-01

    Peritoneal dialysis (PD) program was established in Farwaniya Hospital Kidney Center, Kuwait, in February 2011. Patient recruitment for this modality of treatment was growing steadily. One of the major complications of PD is peritonitis. There is a belief that PD therapy is inferior and carries more complications than hemodialysis, we aimed to show that PD is a good and a non-inferior option for dialysis therapy with comparable outcome in both patient and technique survival. This was a retrospective analysis of all patients who were on PD from February 2011 to December 2014. Peritonitis rate, exit site infection rate, and all-cause mortality rate were all assessed for this period. Peritonitis rate during the 1 st year, 2011, was 0.92 incidents/year. This number had progressively declined in the following years; in 2012, it was 0.65 incidents/year; in 2013, it was 0.58 incidents/year; and in 2014, it was 0.38 incidents/year. This improvement in the rate of peritonitis incidence could be explained by better education of patients and meticulous supervision of the nursing staff. Farwaniya Hospital Kidney Center had an all-cause mortality rate of 9.3% among patients on renal replacement therapy in 2011. In 2012, all-cause mortality rate increased to 17.1%. The following year, 2013, it decreased to 14.3%, and in 2014, all-cause mortality rate dropped further to 7.6%. All-cause mortality rate among PD patients was zero in 2011. In 2012, the all-cause mortality rate in PD was 11.54%, and in 2013, it decreased to 10.52%. Then, again in 2014, the all-cause mortality rate among PD patients was zero. This improvement in all-cause mortality rate could be explained by the better medical care offered to the end-stage renal disease patients, in particular PD patients, in Farwaniya Hospital Kidney Center.

  19. 131I treatment in patients undergoing renal dialysis: our experience

    International Nuclear Information System (INIS)

    Tobarra, Bonifacio; Campos, Pedro A.; Gonzalez Lopez, Antonio; Palma, Juan D.

    2008-01-01

    Radiation Protection issues concerning patients, public and staff must be considered carefully in hemodialysis for chronic renal failure patients scheduled for 131 I high dose therapy. In order to assess the risks related to this medical procedure, hemodialysis clearance of 131 I and contamination measurements were carried out. We have studied 12 hemodialysis procedures corresponding to 2 cases of hyperthyroidism disease (555MBq of 131 I administered) and 3 patients with carcinoma of the thyroid (5550 MBq of 131 I administered). The arterio-venous difference of 131 I across the artificial kidney and dose rate reduction at one meter of patient were measured. Contamination levels of the dialyser machine, filters and tubes were measured after dialysis with a contamination monitor. Direct read-out dosimeters were used to assess the radiation doses to nursery staff involved. The result obtained for mean 131 I clearance in blood was 75±11%. The mean dose rate reduction at one meter of the patient was 58±18%. We also checked that contamination levels for the dialyser machine, filters, tubes and accessories were lower than 10Bq/cm 2 . For the nursery staff the radiation dose was found to be lower than 0.1mSv. (author)

  20. Beta II compact torus experiment plasma equilibrium and power balance

    International Nuclear Information System (INIS)

    Turner, W.C.; Goldenbaum, G.C.; Granneman, E.H.A.; Prono, D.S.; Hartman, C.W.; Taska, J.

    1982-01-01

    In this paper we follow up some of our earlier work that showed the compact torus (CT) plasma equilibrium produced by a magnetized coaxial plasma gun is nearly force free and that impurity radiation plays a dominant role in determining the decay time of plasma currents in present generation experiments

  1. Development and validation of the Consumer Quality index instrument to measure the experience and priority of chronic dialysis patients

    NARCIS (Netherlands)

    van der Veer, Sabine N.; Jager, Kitty J.; Visserman, Ella; Beekman, Robert J.; Boeschoten, Els W.; de Keizer, Nicolette F.; Heuveling, Lara; Stronks, Karien; Arah, Onyebuchi A.

    2012-01-01

    Patient experience is an established indicator of quality of care. Validated tools that measure both experiences and priorities are lacking for chronic dialysis care, hampering identification of negative experiences that patients actually rate important. We developed two Consumer Quality (CQ) index

  2. Biphasic Equilibrium Dialysis of Poly(N-Isopropyl Acrylamide Nanogels Synthesized at Decreased Temperatures for Targeted Delivery of Thermosensitive Bioactives

    Directory of Open Access Journals (Sweden)

    Witold Musial

    2013-01-01

    Full Text Available Hydrogel nanoparticles, referred to also as nanogels, are of special interest for medical and pharmaceutical applications. Due to small size in the range below the diameter of the capillaries, they are proposed as drug delivery carriers. The aim of the study was to estimate the influence of composition and reaction conditions during synthesis of poly-N-isopropyl acrylamide cross-linked by polyethylene glycol diacrylate on the purification rates of the polymer. Six types of thermosensitive nanogels were prepared by surfactant-free dispersion polymerization and assessed in terms of process yield, composition, and size at temperatures below and over volume phase temperature. During the diffusion of impurities, in the course of dialysis, assessed by the conductometric method, the remarkable influence of temperature and initiator concentration on the process was revealed. The release rates varied in the range between 9.63 · 10−2 and 1.39 · 10−1 h−1 in the first stage of the process, whereas in the second stage they were between 2.09 · 10−2 and 6.28 · 10−2 h−1. The evaluated time to obtain acceptable purity of the preparation was estimated to be in the range of 18 days. More detailed research should be directed towards the influence of the structure of obtained material on the purification process.

  3. [Auto-dialysis: an 11-year experience of a hemodialysis center in France].

    Science.gov (United States)

    Montagnac, R; Schillinger, F

    1996-03-30

    Report 11 years of experience with self-managed hemodialysis in patients medically apt for extra-hospital dialysis and living close enough to small outpatient hemodialysis units to become totally self-sufficient. Among the 276 patients with chronic renal failure managed at the hemodialysis center at the Troyes hospital during the 11-year study period from 1984 through 1994, self-managed hemodialysis at small outpatient units was initiated in 127 (46%). None of these 127 patients required medical assistance or specific care during dialysis sessions. At initial hospital admission, only 60/127 (47%) were totally self-sufficient: 52 (41%) were later graft recipients; and 21 (16.5%) had to return to the hospital for a medical or surgical condition incompatible with extra-hospital care but all of these 21 patients remained self-sufficient. Extra-hospital hemodialysis in units close to the patients residence offers patients a better quality of life, even when medical assistance is required. All patients who require hemodialysis can thus be treated at lower cost without compromising quality of treatment. Perfect self-sufficiency may not be a goal in itself, but self-managed hemodialysis can be a very useful technique for patients without major medical problems. Continuing contact with the organizing hemodialysis center guarantees the safety of the system.

  4. Effectiveness of peritonaeal dialysis

    Directory of Open Access Journals (Sweden)

    Jovanović Nataša

    2005-01-01

    Full Text Available Introduction. In the last few years, an increasing number of patients suffering from terminal renal disease of various leading causes was treated with renal replacement therapy. Peritonaeal dialysis involves an exchange of water and solutes between blood in the peritonaeal capillaries and dialysate in the peritonaeal cavum throughout the peritonaeum. Effective dialysis treatment should provide good quality of life, decrease the number of physical complaints, and bring the incidence of morbidity and mortality closer to the incidence of morbidity and mortality in the healthy population. Aim. The aim of this study was the evaluation of peritonaeal transport characteristics and dialysis effectiveness in 58 patients affected by terminal renal disease who underwent peritonaeal dialysis treatment during August 2003 at the Clinic of Nephrology of the Clinical Centre of Serbia. Method. We examined 30 male and 28 female patients, with an average age of 52 years (range 26 to 78 years. The average duration of peritoneal dialysis treatment was 20 months (ranging from 2 to 66 months, and the end-stage renal failure was caused by different leading disease in our patients. We applied different dialysis modalities: continuous ambulatory peritonaeal dialysis (CAPD with three to five 2- or 3-litre exchanges daily, cyclic peritonaeal dialysis (CCPD, intermittent peritonaeal dialysis (IPD, or automatic peritonaeal dialysis (APD, according to the transport characteristics of the peritonaeal membrane, the residual renal function (RRF, and the clinical status of the patients, in order to perform adequate depuration as suggested by the new international criteria. A peritonaeal equilibrium test (PET was performed according to the new international advice; urea and creatinine clearances (Kt/V and Ccr as well as RRF were calculated using the internationally suggested formulas. Results. Most of our patients received effective dialysis treatment, thanks to the modulation of

  5. Development and validation of the Consumer Quality index instrument to measure the experience and priority of chronic dialysis patients.

    Science.gov (United States)

    van der Veer, Sabine N; Jager, Kitty J; Visserman, Ella; Beekman, Robert J; Boeschoten, Els W; de Keizer, Nicolette F; Heuveling, Lara; Stronks, Karien; Arah, Onyebuchi A

    2012-08-01

    Patient experience is an established indicator of quality of care. Validated tools that measure both experiences and priorities are lacking for chronic dialysis care, hampering identification of negative experiences that patients actually rate important. We developed two Consumer Quality (CQ) index questionnaires, one for in-centre haemodialysis (CHD) and the other for peritoneal dialysis and home haemodialysis (PHHD) care. The instruments were validated using exploratory factor analyses, reliability analysis of identified scales and assessing the association between reliable scales and global ratings. We investigated opportunities for improvement by combining suboptimal experience with patient priority. Sixteen dialysis centres participated in our study. The pilot CQ index for CHD care consisted of 71 questions. Based on data of 592 respondents, we identified 42 core experience items in 10 scales with Cronbach's α ranging from 0.38 to 0.88; five were reliable (α ≥ 0.70). The instrument identified information on centres' fire procedures as the aspect of care exhibiting the biggest opportunity for improvement. The pilot CQ index PHHD comprised 56 questions. The response of 248 patients yielded 31 core experience items in nine scales with Cronbach's α ranging between 0.53 and 0.85; six were reliable. Information on kidney transplantation during pre-dialysis showed most room for improvement. However, for both types of care, opportunities for improvement were mostly limited. The CQ index reliably and validly captures dialysis patient experience. Overall, most care aspects showed limited room for improvement, mainly because patients participating in our study rated their experience to be optimal. To evaluate items with high priority, but with which relatively few patients have experience, more qualitative instruments should be considered.

  6. Advanced nursing experience is beneficial for lowering the peritonitis rate in patients on peritoneal dialysis.

    Science.gov (United States)

    Yang, Zhikai; Xu, Rong; Zhuo, Min; Dong, Jie

    2012-01-01

    We explored the relationship between the experience level of nurses and the peritonitis risk in peritoneal dialysis (PD) patients. Our observational cohort study followed 305 incident PD patients until a first episode of peritonitis, death, or censoring. Patients were divided into 3 groups according to the work experience in general medicine of their nurses-that is, least experience (biochemistry, and residual renal function were also recorded. Multivariate Cox regression was used to analyze the association of risks for all-cause and gram-positive peritonitis with patient training provided by nurses at different experience levels. Of the 305 patients, 91 were trained at the initiation of PD by nurses with advanced experience, 100 by nurses with moderate experience, and 114 by nurses with the least experience. Demographic and clinical variables did not vary significantly between the groups. During 13 582 patient-months of follow-up, 129 first episodes of peritonitis were observed, with 48 episodes being attributed to gram-positive organisms. Kaplan-Meier analysis showed that training by nurses with advanced experience predicted the longest period free of first-episode gram-positive peritonitis. After adjustment for some recognized confounders, the advanced experience group was still associated with the lowest risk for first-episode gram-positive peritonitis. The level of nursing experience was not significantly correlated with all-cause peritonitis risk. The experience in general medicine of nurses might help to lower the risk of gram-positive peritonitis among PD patients. These data are the first to indicate that nursing experience in areas other than PD practice can be vital in the training of PD patients.

  7. Experience of using heat citric acid disinfection method in central dialysis fluid delivery system.

    Science.gov (United States)

    Sakuma, Koji; Uchiumi, Nobuko; Sato, Sumihiko; Aida, Nobuhiko; Ishimatsu, Taketo; Igoshi, Tadaaki; Kodama, Yoshihiro; Hotta, Hiroyuki

    2010-09-01

    We applied the heat citric acid disinfection method in the main part of the central dialysis fluid delivery system (MPCDDS), which consists of a multiple-patient dialysis fluid supply unit, dialysis console units, and dialysis fluid piping. This disinfection method has been used for single-patient dialysis machines, but this is the first trial in the MPCDDS. We examined, by points of safety and disinfection effect, whether this disinfection method is comparable to conventional disinfection methods in Japan. The conventional disinfection method is a combination of two disinfectants, sodium hypochlorite and acetic acid, used separately for protein removal and decalcification. Consequently, total microbial counts and endotoxin concentrations fully satisfied the microbiological requirements for standard dialysis fluid of ISO 11663. From our results and discussion, this heat citric acid disinfection method is proved to be safe and reliable for MPCDDS. However, to satisfy the microbiological requirements for ultrapure dialysis fluid, further consideration for this method in MPCDDS including the reverse osmosis device composition and piping is necessary.

  8. A Unified Kinetics and Equilibrium Experiment: Rate Law, Activation Energy, and Equilibrium Constant for the Dissociation of Ferroin

    Science.gov (United States)

    Sattar, Simeen

    2011-01-01

    Tris(1,10-phenanthroline)iron(II) is the basis of a suite of four experiments spanning 5 weeks. Students determine the rate law, activation energy, and equilibrium constant for the dissociation of the complex ion in acid solution and base dissociation constant for phenanthroline. The focus on one chemical system simplifies a daunting set of…

  9. Peritoneal Dialysis

    Science.gov (United States)

    ... include: Infections. An infection of the abdominal lining (peritonitis) is a common complication of peritoneal dialysis. An ... day. You might have a lower risk of peritonitis because you connect and disconnect to the dialysis ...

  10. The Equilibrium Constant for Bromothymol Blue: A General Chemistry Laboratory Experiment Using Spectroscopy

    Science.gov (United States)

    Klotz, Elsbeth; Doyle, Robert; Gross, Erin; Mattson, Bruce

    2011-01-01

    A simple, inexpensive, and environmentally friendly undergraduate laboratory experiment is described in which students use visible spectroscopy to determine a numerical value for an equilibrium constant, K[subscript c]. The experiment correlates well with the lecture topic of equilibrium even though the subject of the study is an acid-base…

  11. USE OF SILDENAFIL (VIAGRA® FOR ERECTILE DYSFUNCTION IN DIALYSIS PATIENTS – OUR FIRST EXPERIENCE

    Directory of Open Access Journals (Sweden)

    Bojan Vujkovac

    2002-01-01

    Full Text Available Background. Male patients with end stage renal disease often report erectile dysfunction, which is very common especially in younger males. Impotence is reported to exceed 50% in male chronic renal failure patients, and is present in 65% of such patients undergoing hemodialysis. Numerous etiological factors have been reported as possible cause for sexual dysfunction. Sildenafil (Viagra®, a potent specific inhibitor of cGMP phosphodiesterase, was used in this case study to improve erectile dysfunction in dialysis male patients.Methods and results. During 12 weeks we treated 4 dialysis patients. 2 patients were treated with peritoneal dialysis and 2 patients were in the program of chronic hemodialysis. All patients were in the program of dialysis for more than 24 months, and reported erectile dysfunction and impotence after they had started with dialysis treatment. Sildenafil was used in the treatment. The dosage schedule for sildenafil was 50mg/ week orally for 2 weeks followed by 100 mg/week for the next 10 weeks if there was no effect on initial dosage. Efficacy of treatment was evaluated by means of the International Index of Erectile Dysfunction. All 4 patients reported no significant effect on initial dose. With higher dose of sildenafil treatment was overwhelmingly successful, with reported prolonged improvement of erectile dysfunction for 42 to 72 hours. Side effects were present only in 1 patient who had severe headaches after higher dose. No patients experienced priapism.Conclusions. There have been only few reports in the literature on the use of sildenafil in dialysis patients. Our small case study suggests that sildenafil could be successfully and safely used for treatment of erectile dysfunction also in dialysis patients. A large trial would be necessary to confirm the efficacy of the drug for this specific group of patients.

  12. Mechanical complications of continuous ambulatory peritoneal dialysis: Experience at the Ibn Sina University Hospital.

    Science.gov (United States)

    Flayou, Kaoutar; Ouzeddoun, Naima; Bayahia, Rabia; Rhou, Hakima; Benamar, Loubna

    2016-01-01

    Peritoneal dialysis is a new renal replacement therapy recently introduced in Morocco since 2006. Continuous ambulatory peritoneal dialysis has proven to be as effective as hemodialysis. However, it is associated with several complications. The aim of this study was to evaluate the outcome of complications in patients treated with peritoneal dialysis at our center. The nature of non-infectious complications was noted during follow-up in these patients. Fiftyseven complications were noted among 34 patients between June 2006 and June 2014. Catheter migration was the most common complication (36.8%), followed by obstruction (14%), dialysate leaks (14%), hemorrhagic complications (10.5%) and, finally, hernia (12.2%), catheter perforation (5.2%) and externalization (3.5%).

  13. Peritoneal Dialysis to Treat Patients with Acute Kidney Injury-The Saving Young Lives Experience in West Africa: Proceedings of the Saving Young Lives Session at the First International Conference of Dialysis in West Africa, Dakar, Senegal, December 2015.

    Science.gov (United States)

    Abdou, Niang; Antwi, Sampson; Koffi, Laurence Adonis; Lalya, Francis; Adabayeri, Victoria May; Nyah, Norah; Palmer, Dennis; Brusselmans, Ariane; Cullis, Brett; Feehally, John; McCulloch, Mignon; Smoyer, William; Finkelstein, Fredric O

    2017-01-01

    In December 2015, as part of the First African Dialysis Conference organized in Dakar, Senegal, 5 physicians from West African countries who have participated in the Saving Young Lives Program reviewed their experiences establishing peritoneal dialysis (PD) programs to treat patients with acute kidney injury (AKI). Thus far, nearly 200 patients have received PD treatment in these countries. The interaction and discussion amongst the participants at the meeting was meaningful and informative. The presentations highlighted the creativity, conviction, and determination of the physicians in overcoming the various barriers and challenges they encountered to establish PD/AKI programs. Hopefully, these successes and the increased awareness of the importance of early diagnosis and treatment of AKI will inspire much needed support from government, hospital, and international organizations. Copyright © 2017 International Society for Peritoneal Dialysis.

  14. Field reversal experiments (FRX). [Equilibrium, confinement, and stability

    Energy Technology Data Exchange (ETDEWEB)

    Linford, R.K.; Armstrong, W.T.; Platts, D.A.; Sherwood, E.G.

    1978-01-01

    The equilibrium, confinement, and stability properties of the reversed-field configuration (RFC) are being studied in two theta-pinch facilities. The RFC is an elongated toroidal plasma confined in a purely poloidal field geometry. The open field lines of the linear theta pinch support the closed-field RFC much like the vertical field centers the toroidal plasma in a tokamak. Depending on stability and confinement properties, the RFC might be used to greatly reduce the axial losses in linear fusion devices such as mirrors, theta pinches, and liners. The FRX systems produce RFC's with a major radius R = 2-6 cm, minor radius a approximately 2 cm, and a total length l approximately 35 cm. The observed temperatures are T/sub e/ approximately 100 eV and T/sub i/ = 150-350 eV with a peak density n approximately 2 x 10/sup 15/ cm/sup -3/. After the plasma reaches equilibrium, the RFC remains stable for up to 30 ..mu..s followed by the rapid growth of the rotational m = 2 instability, which terminates the confinement. During the stable equilibrium, the particle and energy confinement times are more than 10 times longer than in an open-field system. The behavior of the m = 2 mode qualitatively agrees with the theoretically predicted instability for rotational velocities exceeding some critical value.

  15. 32 years' experience of peritoneal dialysis-related peritonitis in a university hospital

    NARCIS (Netherlands)

    van Esch, Sadie; Krediet, Raymond T.; Struijk, Dirk G.

    2014-01-01

    Peritonitis in peritoneal dialysis (PD) patients can lead to technique failure and contributes to infection-related mortality. Peritonitis prevention and optimization of treatment are therefore important in the care for PD patients. In the present study, we analyzed the incidence of peritonitis,

  16. Post-Dilution on Line Haemodiafiltration with Citrate Dialysate: First Clinical Experience in Chronic Dialysis Patients

    Directory of Open Access Journals (Sweden)

    Vincenzo Panichi

    2013-01-01

    Full Text Available Background. Citrate has anticoagulative properties and favorable effects on inflammation, but it has the potential hazards of inducing hypocalcemia. Bicarbonate dialysate (BHD replacing citrate for acetate is now used in chronic haemodialysis but has never been tested in postdilution online haemodiafiltration (OL-HDF. Methods. Thirteen chronic stable dialysis patients were enrolled in a pilot, short-term study. Patients underwent one week (3 dialysis sessions of BHD with 0.8 mmol/L citrate dialysate, followed by one week of postdilution high volume OL-HDF with standard bicarbonate dialysate, and one week of high volume OL-HDF with 0.8 mmol/L citrate dialysate. Results. In citrate OL-HDF pretreatment plasma levels of C-reactive protein and β2-microglobulin were significantly reduced; intra-treatment plasma acetate levels increased in the former technique and decreased in the latter. During both citrate techniques (OL-HDF and HD ionized calcium levels remained stable within the normal range. Conclusions. Should our promising results be confirmed in a long-term study on a wider population, then OL-HDF with citrate dialysate may represent a further step in improving dialysis biocompatibility.

  17. Numerical experiments with rubble piles : equilibrium shapes and spins

    NARCIS (Netherlands)

    Richardson, Derek C.; Elankumaran, Pradeep; Sanderson, Robyn E.

    2005-01-01

    We present numerical experiments investigating the shape and spin limits of self-gravitating "perfect" rubble piles that consist of identical, smooth, rigid, spherical particles with configurable normal coefficient of restitution and no sliding friction. Such constructs are currently employed in a

  18. Equilibrium system analysis in a tokamak ignition experiment

    International Nuclear Information System (INIS)

    Carrera, R.; Weldon, W.F.; Woodson, H.H.

    1989-10-01

    The objective of the IGNITEX Project is to produce and control ignited plasmas for scientific study in the simplest and least expensive way possible. The original concept was proposed by both physics and engineering researchers along the following line of thought. Question: Is there any theoretically simple, compact and reliable way of achieving fusion ignition according to the results of the fusion research program for the last decades? Answer: Yes. An experiment to be carried out in an ohmically heated compact tokamak device with 20 T field on plasma axis. Question: Is there any practical way to carry out that experiment at low cost in the near term? Answer: Yes. Using a single-turn coil magnet system with homopolar power supplies

  19. Equilibrium system analysis in a tokamak ignition experiment. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Carrera, R.; Weldon, W.F.; Woodson, H.H.

    1989-10-01

    The objective of the IGNITEX Project is to produce and control ignited plasmas for scientific study in the simplest and least expensive way possible. The original concept was proposed by both physics and engineering researchers along the following line of thought. Question: Is there any theoretically simple, compact and reliable way of achieving fusion ignition according to the results of the fusion research program for the last decades? Answer: Yes. An experiment to be carried out in an ohmically heated compact tokamak device with 20 T field on plasma axis. Question: Is there any practical way to carry out that experiment at low cost in the near term? Answer: Yes. Using a single-turn coil magnet system with homopolar power supplies.

  20. Equilibrium system analysis in a tokamak ignition experiment

    Energy Technology Data Exchange (ETDEWEB)

    Carrera, R.; Weldon, W.F.; Woodson, H.H.

    1989-10-01

    The objective of the IGNITEX Project is to produce and control ignited plasmas for scientific study in the simplest and least expensive way possible. The original concept was proposed by both physics and engineering researchers along the following line of thought. Question: Is there any theoretically simple, compact and reliable way of achieving fusion ignition according to the results of the fusion research program for the last decades Answer: Yes. An experiment to be carried out in an ohmically heated compact tokamak device with 20 T field on plasma axis. Question: Is there any practical way to carry out that experiment at low cost in the near term Answer: Yes. Using a single-turn coil magnet system with homopolar power supplies.

  1. Two years experience with tunneled dialysis catheters in patients requiring haemodialysis

    International Nuclear Information System (INIS)

    Raheem, A.; Rana, A. I.; Ramzan, M.; Shah, R. A.; Mehmood, S. N.; Naseem, S.

    2014-01-01

    Objective: To look for survival rate and major reasons behind the failure of tunnelled dialysis catheters in patients on haemodialysis. Methods: The retrospective study was conducted at the Department of Interventional Radiology, Shifa International Hospital, Islamabad, and comprised records of 100 consecutive subjects from a list of patients in whom tunnelled cuffed catheters were placed from February 2009 to January 2011 and were followed up for two years. Data was collected on a proforma from the hospital database and medical records of patients. SPSS 19 was used for statistical analysis. Results: Of the total 122 catheters placed in 100 patients, 49(40.16%) were lost to follow-up. Of the remaining 73(59.83%) catheters, 38(52%) had achieved their desired function, while 35(48%) failed to achieve the target duration. Among the reasons of catheter failure, infection was the commonest at 13(37.14%) with infection rate of 0.24 per 1000 catheter days. According to Kaplan Meier analysis, catheter survival rates at 60, 90 and 180 days were 89%, 77% and 64% respectively. Mean effective duration of catheter was 129+-117 days. Conclusion: Tunnelled dialysis catheters can be safely used as vascular access till the maturation of fistula and may be an alternative to Arterio-Venous Fistula or graft for long-term vascular access if indicated. (author)

  2. Connecting Solubility, Equilibrium, and Periodicity in a Green, Inquiry Experiment for the General Chemistry Laboratory

    Science.gov (United States)

    Cacciatore, Kristen L.; Amado, Jose; Evans, Jason J.; Sevian, Hannah

    2008-01-01

    We present a novel first-year chemistry laboratory experiment that connects solubility, equilibrium, and chemical periodicity concepts. It employs a unique format that asks students to replicate experiments described in different sample lab reports, each lacking some essential information, rather than follow a scripted procedure. This structure is…

  3. North American experience with Low protein diet for Non-dialysis-dependent chronic kidney disease.

    Science.gov (United States)

    Kalantar-Zadeh, Kamyar; Moore, Linda W; Tortorici, Amanda R; Chou, Jason A; St-Jules, David E; Aoun, Arianna; Rojas-Bautista, Vanessa; Tschida, Annelle K; Rhee, Connie M; Shah, Anuja A; Crowley, Susan; Vassalotti, Joseph A; Kovesdy, Csaba P

    2016-07-19

    Whereas in many parts of the world a low protein diet (LPD, 0.6-0.8 g/kg/day) is routinely prescribed for the management of patients with non-dialysis-dependent chronic kidney disease (CKD), this practice is infrequent in North America. The historical underpinnings related to LPD in the USA including the non-conclusive results of the Modification of Diet in Renal Disease Study may have played a role. Overall trends to initiate dialysis earlier in the course of CKD in the US allowed less time for LPD prescription. The usual dietary intake in the US includes high dietary protein content, which is in sharp contradistinction to that of a LPD. The fear of engendering or worsening protein-energy wasting may be an important handicap as suggested by a pilot survey of US nephrologists; nevertheless, there is also potential interest and enthusiasm in gaining further insight regarding LPD's utility in both research and in practice. Racial/ethnic disparities in the US and patients' adherence are additional challenges. Adherence should be monitored by well-trained dietitians by means of both dietary assessment techniques and 24-h urine collections to estimate dietary protein intake using urinary urea nitrogen (UUN). While keto-analogues are not currently available in the USA, there are other oral nutritional supplements for the provision of high-biologic-value proteins along with dietary energy intake of 30-35 Cal/kg/day available. Different treatment strategies related to dietary intake may help circumvent the protein- energy wasting apprehension and offer novel conservative approaches for CKD management in North America.

  4. Peritoneal Dialysis and Retroperitoneal Laparoscopic Radical Nephrectomy: A Favorable Experience With a Patient Complicated by Renal Cell Carcinoma

    Directory of Open Access Journals (Sweden)

    Reika Imai

    2017-12-01

    Full Text Available Peritoneal dialysis (PD is an accepted modality for managing end-stage kidney disease. We herein report a 75-year-old female patient on chronic PD who was complicated by renal cell carcinoma. She was successfully treated with retroperitoneal laparoscopic radical nephrectomy followed by a prompt resumption of the procedure. Various surgeries disturbing the abdominal wall integrity often disrupt the regular PD schedule, and using minimally invasive approaches is therefore an attractive therapeutic option. Our experience emphasizes the feasibility and safety of a retroperitoneal approach–based laparoscopic technique based on several empirical examples. However, systemic studies on this topic are obviously lacking, so we strongly recommend the accumulation of more cases similar to our own. Several surgical concerns that need to be dealt with among PD patients are also discussed.

  5. 32 Years’ Experience of Peritoneal Dialysis-Related Peritonitis in a University Hospital

    Science.gov (United States)

    van Esch, Sadie; Krediet, Raymond T.; Struijk, Dirk G.

    2014-01-01

    ♦ Background: Peritonitis in peritoneal dialysis (PD) patients can lead to technique failure and contributes to infection-related mortality. Peritonitis prevention and optimization of treatment are therefore important in the care for PD patients. In the present study, we analyzed the incidence of peritonitis, causative pathogens, clinical outcomes, and trends in relation to three major treatment changes that occurred from 1979 onward: use of a disconnect system since 1988, daily mupirocin at the exit-site since 2001, and exclusive use of biocompatible dialysis solutions since 2004. ♦ Methods: In this analysis of prospectively collected data, we included peritonitis episodes from the start of PD at our center in August 1979 to July 2010. Incident PD patients were allocated to one of four groups: Group 1 - 182 patients experiencing 148 first peritonitis episodes between 1979 and 1987, before the introduction of the disconnect system; Group 2 - 352 patients experiencing 239 first episodes of peritonitis between 1988 and 2000, before implementation of daily mupirocin application at the catheter exit-site; Group 3 - 79 patients experiencing 50 first peritonitis episodes between 2001 and 2003, before the switch to biocompatible solutions; and Group 4-118 patients experiencing 91 first peritonitis episodes after 2004. Cephradine was used as initial antibiotic treatment. ♦ Results: In 32 years, 731 adult patients started PD, and 2234 episodes of peritonitis in total were diagnosed and treated. Of those episodes, 88% were cured with medical treatment only, and 10% resulted in catheter removal. In 3% of the episodes, the patient died during peritonitis. Median time to a first peritonitis episode increased from 40 days for group 1 to 150 for group 2, 269 for group 3, and 274 for group 4. The overall peritonitis rate and the gram-positive and gram-negative peritonitis rates showed a time-trend of decline. However, the duration of antibiotic treatment increased over time

  6. Psycho-social Features of Chronic Dialysis Patients in Saudi Arabia: Experience of one Centre

    Directory of Open Access Journals (Sweden)

    AL-Homrany Mohammed

    2001-01-01

    Full Text Available The goals of chronic dialysis treatment for end-stage renal disease (ESRD patients include restoration of the highest achievable state of personal physical health and preservation as well as restoration and development of the highest level of psychological and social functions. We conducted this study to evaluate factors influencing the process of adaptation such as religious faith, economic status and extended family-tribal system. It was hoped that studying these factors might provide further dimension to our understanding of the psychopathology of ESRD patients, and to help offer new ideas to improve the quality of their lives. A sample comprising 54 patients with ESRD was studied in Abha hemodialysis centre in Southern Saudi Arabia. The socio-demographic characteristics, clinical and laboratory data were collected. The psychiatric status of the patients was evaluated using a structured "The Comprehensive Psychiatric Rating Scale" (CPRS clinical interview. The result indicated that the major co-morbidity (in 60% of these patients was a depressive illness due to renal failure diagnosable according to DSM-IV criteria. Our study suggests the need for specific anti-depressant treatment in order to ameliorate many distressing symptoms, which may affect the quality of these patients′ life. Concomitant social problems of poverty, absence of spouse and illiteracy, dictate a more prompt attitude in initiating support systems and attention to providing leisure activities.

  7. Outcomes of Peritonitis in Children on Peritoneal Dialysis: A 25-Year Experience at Severance Hospital

    Science.gov (United States)

    Lee, Kyong Ok; Park, Se Jin; Kim, Ji Hong; Lee, Jae Seung; Kim, Pyung Kil

    2013-01-01

    Purpose Relatively little is known on the microbiology, risk factors and outcomes of peritoneal dialysis (PD)-associated peritonitis in Korean children. We performed this study in order to evaluate the incidence, treatment and clinical outcomes of peritonitis in pediatric PD patients at Severance Hospital. Materials and Methods We analyzed data from 57 PD patients younger than 18 years during the period between June 1, 1986 and December 31, 2011. The collected data included gender, age at commencement of PD, age at peritonitis, incidence of peritonitis, underlying causes of end stage renal disease, microbiology of peritonitis episodes, antibiotics sensitivity, modality and outcomes of PD. Results We found 56 episodes of peritonitis in 23 of the 57 PD patients (0.43 episodes/patient-year). Gram-positive bacteria were the most commonly isolated organisms (40 episodes, 71.4%). Peritonitis developed in 17 patients during the first 6 months following initiation of PD (73.9%). Peritonitis episodes rarely resulted in relapse or the need for permanent hemodialysis and no patient deaths were directly attributable to peritonitis. Antibiotic regimens included cefazolin+tobramycin from the years of 1986 to 2000 and cefazolin+ceftazidime from the years of 2001 to 2011. While antibiotic therapy was successful in 48 episodes (85.7%), the treatment was ineffective in 8 episodes (14.3%). The rate of continuous ambulatory PD (CAPD) peritonitis was statistically higher than that of automated PD (APD) (p=0.025). Conclusion Peritonitis was an important complication of PD therapy and we observed a higher incidence of PD peritonitis in patients with CAPD when compared to APD. PMID:23709435

  8. Dynamics of a grassland ecosystem: botanical equilibrium in the Park Grass Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Silvertown, J

    1980-01-01

    The published results of the Park Grass Experiment (PGE), begun in 1856, provide up to 30 yr of annual data which may be used to determine whether the botanical composition of these grasslands was at equilibrium. Data covering a period exceeding 80 yr are available to test for relationships between hay yield (biomass), species diversity, species number and time. Species diversity and species number show negative relationships with plot biomass and with pH. These relationships were constant over time. The effects of biomass and pH on species number and species diversity were additive. Analysis of the flora of nine plots, each divided into grasses, legumes and a miscellaneous component showed that these components were at equilibrium. The effect of various endogenous factors on this botanical equilibrium was examined. No regular or irregular cycles of component biomass operating between years were detected and it is inferred that populations were regulated by processes operating within individual years. The biomasses of all three components were positively correlated within an unfertilized plot but the floristic components of plots receiving a fertilizer treatment showed few within-plot correlations. By contrast between-plot correlations of components were common for all plots with the exception of those receiving nitrogen fertilizer. The mechanisms of population regulation which maintained the park grass ecosystem at equilibrium are discussed and tests for these are proposed.

  9. Using Controlled Landslide Initiation Experiments to Test Limit-Equilibrium Analyses of Slope Stability

    Science.gov (United States)

    Reid, M. E.; Iverson, R. M.; Brien, D. L.; Iverson, N. R.; Lahusen, R. G.; Logan, M.

    2004-12-01

    Most studies of landslide initiation employ limit equilibrium analyses of slope stability. Owing to a lack of detailed data, however, few studies have tested limit-equilibrium predictions against physical measurements of slope failure. We have conducted a series of field-scale, highly controlled landslide initiation experiments at the USGS debris-flow flume in Oregon; these experiments provide exceptional data to test limit equilibrium methods. In each of seven experiments, we attempted to induce failure in a 0.65m thick, 2m wide, 6m3 prism of loamy sand placed behind a retaining wall in the 31° sloping flume. We systematically investigated triggering of sliding by groundwater injection, by prolonged moderate-intensity sprinkling, and by bursts of high intensity sprinkling. We also used vibratory compaction to control soil porosity and thereby investigate differences in failure behavior of dense and loose soils. About 50 sensors were monitored at 20 Hz during the experiments, including nests of tiltmeters buried at 7 cm spacing to define subsurface failure geometry, and nests of tensiometers and pore-pressure sensors to define evolving pore-pressure fields. In addition, we performed ancillary laboratory tests to measure soil porosity, shear strength, hydraulic conductivity, and compressibility. In loose soils (porosity of 0.52 to 0.55), abrupt failure typically occurred along the flume bed after substantial soil deformation. In denser soils (porosity of 0.41 to 0.44), gradual failure occurred within the soil prism. All failure surfaces had a maximum length to depth ratio of about 7. In even denser soil (porosity of 0.39), we could not induce failure by sprinkling. The internal friction angle of the soils varied from 28° to 40° with decreasing porosity. We analyzed stability at failure, given the observed pore-pressure conditions just prior to large movement, using a 1-D infinite-slope method and a more complete 2-D Janbu method. Each method provides a static

  10. Dialysis centers - what to expect

    Science.gov (United States)

    ... kidneys - dialysis centers; Dialysis - what to expect; Renal replacement therapy - dialysis centers; End-stage renal disease - dialysis ... to a tube that connects to the dialysis machine. Your blood will flow through the tube, into ...

  11. Perceptions and experiences of financial incentives: a qualitative study of dialysis care in England.

    Science.gov (United States)

    Abma, Inger; Jayanti, Anuradha; Bayer, Steffen; Mitra, Sandip; Barlow, James

    2014-02-12

    The objective of the study was to understand the extent to which financial incentives such as Payment by Results and other payment mechanisms motivate kidney centres in England to change their practices. The study followed a qualitative design. Data collection involved 32 in-depth semistructured interviews with healthcare professionals and managers, focusing on their subjective experience of payment structures. Participants were kidney healthcare professionals, clinical directors, kidney centre managers and finance managers. Healthcare commissioners from different parts of England were also interviewed. Participants worked at five kidney centres from across England. The selection was based on the prevalence of home haemodialysis, ranging from low (8%) prevalence, with at least one centre in each one of these categories at the time of selection. While the tariff for home haemodialysis is not a clear incentive for its adoption due to uncertainty about operational costs, Commissioning for Quality and Innovation (CQUIN) targets and the Best Practice Tariff for vascular access were seen by our case study centres as a motivator to change practices. The impact of financial incentives designed at a policy level is influenced by the understanding of cost and benefits at the local operational level. In a situation where costs are unclear, incentives which are based on the improvement of profit margins have a smaller impact than incentives which provide an additional direct payment, even if this extra financial support is relatively small.

  12. Hot electron plasma equilibrium and stability in the Constance B mirror experiment

    International Nuclear Information System (INIS)

    Chen, Xing.

    1988-04-01

    An experimental study of the equilibrium and macroscopic stability property of an electron cyclotron resonance heating (ECRH) generated plasma in a minimum-B mirror is presented. The Constance B mirror is a single cell quadrupole magnetic mirror in which high beta (β ≤ 0.3) hot electron plasmas (T/sub e/≅400 keV) are created with up to 4 kW of ECRH power. The plasma equilibrium profile is hollow and resembles the baseball seam geometry of the magnet which provides the confining magnetic field. This configuration coincides with the drift orbit of deeply trapped particles. The on-axis hollowness of the hot electron density profile is 50 /+-/ 10%, and the pressure profile is at least as hollow as, if not more than, the hot electron density profile. The hollow plasma equilibrium is macroscopically stable and generated in all the experimental conditions in which the machine has been operated. Small macroscopic plasma fluctuations in the range of the hot electron curvature drift frequency sometimes occur but their growth rate is small (ω/sub i//ω/sub r/ ≤ 10 -2 ) and saturate at very low level (δB//bar B/ ≤ 10 -3 ). Particle drift reversal is predicted to occur for the model pressure profile which best fits the experimental data under the typical operating conditions. No strong instability is observed when the plasma is near the drift reversal parameter regime, despite a theoretical prediction of instability under such conditions. The experiment shows that the cold electron population has no stabilizing effect to the hot electrons, which disagrees with current hot electron stability theories and results of previous maximum-B experiments. A theoretical analysis using MHD theory shows that the compressibility can stabilize a plasma with a hollowness of 20--30% in the Constance B mirror well. 57 refs

  13. Determination of the Equilibrium Constants of a Weak Acid: An Experiment for Analytical or Physical Chemistry

    Science.gov (United States)

    Bonham, Russell A.

    1998-05-01

    A simple experiment, utilizing readily available equipment and chemicals, is described. It allows students to explore the concepts of chemical equilibria, nonideal behavior of aqueous solutions, least squares with adjustment of nonlinear model parameters, and errors. The relationship between the pH of a solution of known initial concentration and volume of a weak acid as it is titrated by known volumes of a monohydroxy strong base is developed rigorously assuming ideal behavior. A distinctive feature of this work is a method that avoids dealing with the problems presented by equations with multiple roots. The volume of base added is calculated in terms of a known value of the pH and the equilibrium constants. The algebraic effort involved is nearly the same as the alternative of deriving a master equation for solving for the hydrogen ion concentration or activity and results in a more efficient computational algorithm. This approach offers two advantages over the use of computer software to solve directly for the hydrogen ion concentration. First, it avoids a potentially lengthy iterative procedure encountered when the polynomial exceeds third order in the hydrogen ion concentration; and second, it provides a means of obtaining results with a hand calculator that can prove useful in checking computer code. The approach is limited to weak solutions to avoid dealing with molalities and to insure that the Debye-Hückel limiting law is applicable. The nonlinear least squares algorithm Nonlinear Fit, found in the computational mathematics library Mathematica, is utilized to fit the measured volume of added base to the calculated value as a function of the measured pH subject to variation of all the equilibrium constants as parameters (including Kw). The experiment emphasizes both data collection and data analysis aspects of the problem. Data for the titration of phosphorous acid, H3PO3, by NaOH are used to illustrate the approach. Fits of the data without corrections

  14. Reflective equilibrium and empirical data: third person moral experiences in empirical medical ethics.

    Science.gov (United States)

    De Vries, Martine; Van Leeuwen, Evert

    2010-11-01

    In ethics, the use of empirical data has become more and more popular, leading to a distinct form of applied ethics, namely empirical ethics. This 'empirical turn' is especially visible in bioethics. There are various ways of combining empirical research and ethical reflection. In this paper we discuss the use of empirical data in a special form of Reflective Equilibrium (RE), namely the Network Model with Third Person Moral Experiences. In this model, the empirical data consist of the moral experiences of people in a practice. Although inclusion of these moral experiences in this specific model of RE can be well defended, their use in the application of the model still raises important questions. What precisely are moral experiences? How to determine relevance of experiences, in other words: should there be a selection of the moral experiences that are eventually used in the RE? How much weight should the empirical data have in the RE? And the key question: can the use of RE by empirical ethicists really produce answers to practical moral questions? In this paper we start to answer the above questions by giving examples taken from our research project on understanding the norm of informed consent in the field of pediatric oncology. We especially emphasize that incorporation of empirical data in a network model can reduce the risk of self-justification and bias and can increase the credibility of the RE reached. © 2009 Blackwell Publishing Ltd.

  15. Percutaneous insertion of peritoneal dialysis catheters using ultrasound and fluoroscopic guidance: A single centre experience and review of literature

    International Nuclear Information System (INIS)

    De Boo, Diederick W.; Mott, Nigel; Tregaskis, Peter; Quach, Trung; Menahem, Solomon; Walker, Rowan G.; Koukounaras, Jim

    2015-01-01

    Various methods of peritoneal dialysis (PD) catheter insertion are available. The purpose of this study was to evaluate a percutaneous insertion technique using ultrasound (US) and fluoroscopy performed under conscious sedation and as day case procedure. Data of 87 percutaneous inserted dialysis catheters were prospectively collected, including patients' age, gender, body mass index, history of previous abdominal surgery and cause of end stage renal failure. Length of hospital stay, early complications and time to first use were also recorded. Institutional review board approval was obtained. A 100% technical success rate was observed. Early complications included bleeding (n = 3), catheter dysfunction (n = 6), exit site infection (n = 1) and exit site leakage (n = 1). All cases of catheter dysfunction and one case of bleeding required surgical revision. Median time of follow-up was 18 months (range 3–35), and median time from insertion to first use was days 14 (1–47). Of the 82 patients who started dialysis, 20 (23%) ceased PD at some stage during follow-up. Most frequently encountered reasons include deteriorating patient cognitive or functional status (n = 5), successful transplant kidney (n = 4) and pleuro-peritoneal fistula (n = 4). Sixty-two (71%) PD catheter insertions were performed as day case. The remaining insertions were performed on patients already admitted to the hospital. Percutaneous insertion of dialysis catheter using US and fluoroscopy is not only safe but can be performed as day case procedure in most patients, even with a medical history of abdominal surgery and/or obesity.

  16. Patient with a total artificial heart maintained on outpatient dialysis while listed for combined organ transplant, a single center experience.

    Science.gov (United States)

    Hanna, Ramy M; Hasnain, Huma; Kamgar, Mohammad; Hanna, Mina; Minasian, Raffi; Wilson, James

    2017-10-01

    Advanced mechanical circulatory support is increasingly being used with more sophisticated devices that can deliver pulsatile rather than continuous flow. These devices are more portable as well, allowing patients to await cardiac transplantation in an outpatient setting. It is known that patients with renal failure are at increased risk for developing worsening acute kidney injury during implantation of a ventricular assist device (VAD) or more advanced modalities like a total artificial heart (TAH). Dealing with patients who have an implanted TAH who develop renal failure has been a challenge with the majority of such patients having to await a combined cardiac and renal transplant prior to transition to outpatient care. Protocols do exist for VAD implanted patients to be transitioned to outpatient dialysis care, but there are no reported cases of TAH patients with end stage renal disease (ESRD) being successfully transitioned to outpatient dialysis care. In this report, we identify a patient with a TAH and ESRD transitioned successfully to outpatient hemodialysis and maintained for more than 2 years, though he did not survive to transplant. It is hoped that this report will raise awareness of this possibility, and assist in the development of protocols for similar patients to be successfully transitioned to outpatient dialysis care. © 2017 International Society for Hemodialysis.

  17. Plasma Shape Control on the National Spherical Torus Experiment using Real-time Equilibrium Reconstruction

    International Nuclear Information System (INIS)

    Gates, D.A.; Ferron, J.R.; Bell, M.; Gibney, T.; Johnson, R.; Marsala, R.J.; Mastrovito, D.; Menard, J.E.; Mueller, D.; Penaflor, B.; Sabbagh, S.A.; Stevenson, T.

    2005-01-01

    Plasma shape control using real-time equilibrium reconstruction has been implemented on the National Spherical Torus Experiment (NSTX). The rtEFIT code originally developed for use on DIII-D was adapted for use on NSTX. The real-time equilibria provide calculations of the flux at points on the plasma boundary, which is used as input to a shape control algorithm known as isoflux control. The flux at the desired boundary location is compared to a reference flux value, and this flux error is used as the basic feedback quantity for the poloidal-field coils on NSTX. The hardware that comprises the control system is described, as well as the software infrastructure. Examples of precise boundary control are also presented

  18. Computer experiments on dynamical cloud and space time fluctuations in one-dimensional meta-equilibrium plasmas

    International Nuclear Information System (INIS)

    Rouet, J.L.; Feix, M.R.

    1996-01-01

    The test particle picture is a central theory of weakly correlated plasma. While experiments and computer experiments have confirmed the validity of this theory at thermal equilibrium, the extension to meta-equilibrium distributions presents interesting and intriguing points connected to the under or over-population of the tail of these distributions (high velocity) which have not yet been tested. Moreover, the general dynamical Debye cloud (which is a generalization of the static Debye cloud supposing a plasma at thermal equilibrium and a test particle of zero velocity) for any test particle velocity and three typical velocity distributions (equilibrium plus two meta-equilibriums) are presented. The simulations deal with a one-dimensional two-component plasma and, moreover, the relevance of the check for real three-dimensional plasma is outlined. Two kinds of results are presented: the dynamical cloud itself and the more usual density (or energy) fluctuation spectrums. Special attention is paid to the behavior of long wavelengths which needs long systems with very small graininess effects and, consequently, sizable computation efforts. Finally, the divergence or absence of energy in the small wave numbers connected to the excess or lack of fast particles of the two above mentioned meta-equilibrium is exhibited. copyright 1996 American Institute of Physics

  19. Dialysis Facility Compare

    Data.gov (United States)

    U.S. Department of Health & Human Services — Dialysis Facility Compare helps you find detailed information about Medicare-certified dialysis facilities. You can compare the services and the quality of care that...

  20. Critical Care Dialysis System

    Science.gov (United States)

    1992-01-01

    Organon Teknika Corporation's REDY 2000 dialysis machine employs technology originally developed under NASA contract by Marquardt Corporation. The chemical process developed during the project could be applied to removing toxic waste from used dialysis fluid. This discovery led to the development of a kidney dialysis machine using "sorbent" dialysis, a method of removing urea from human blood by treating a dialysate solution. The process saves electricity and, because the need for a continuous water supply is eliminated, the patient has greater freedom.

  1. Myths in peritoneal dialysis.

    Science.gov (United States)

    Lee, Martin B; Bargman, Joanne M

    2016-11-01

    To clarify misconceptions about the feasibility and risks of peritoneal dialysis that unnecessarily limit peritoneal dialysis uptake or continuation in patients for whom peritoneal dialysis is the preferred dialysis modality. The inappropriate choice of haemodialysis as a result of these misconceptions contributes to low peritoneal dialysis penetrance, increases transfer from peritoneal dialysis to haemodialysis, increases expenditure on haemodialysis and compromises quality of life for these patients. Peritoneal dialysis is an excellent renal replacement modality that is simple, cost-effective and provides comparable clinical outcomes to conventional in-centre haemodialysis. Unfortunately, many patients are deemed unsuitable to start or continue peritoneal dialysis because of false or inaccurate beliefs about peritoneal dialysis. Here, we examine some of these 'myths' and critically review the evidence for and against each of them. We review the feasibility and risk of peritoneal dialysis in patients with prior surgery, ostomies, obesity and mesh hernia repairs. We examine the fear of mediastinitis with peritoneal dialysis after coronary artery bypass graft surgery and the belief that the use of hypertonic glucose dialysate causes peritoneal membrane failure. By clarifying common myths about peritoneal dialysis, we hope to reduce overly cautious practices surrounding this therapy.

  2. Comparison of peritonitis rates and patient survival in automated and continuous ambulatory peritoneal dialysis: a 10-year single center experience.

    Science.gov (United States)

    El-Reshaid, Wael; Al-Disawy, Hanan; Nassef, Hossameldeen; Alhelaly, Usama

    2016-09-01

    Peritonitis is a common complication in patients undergoing continuous ambulatory peritoneal dialysis (CAPD) and automated peritoneal dialysis (APD). In this retrospective study, peritonitis rates and patient survival of 180 patients on CAPD and 128 patients on APD were compared in the period from January 2005 to December 2014 at Al-Nafisi Center in Kuwait. All patients had prophylactic topical mupirocin at catheter exit site. Patients on CAPD had twin bag system with Y transfer set. The peritonitis rates were 1 in 29 months in CAPD and 1 in 38 months in APD (p peritonitis free patients over 10-year period in CAPD and APD were 49 and 60%, respectively (p peritonitis was 10.25 ± 3.1 months in CAPD compared to 16.1 ± 4 months in APD (p peritonitis was 13.1 ± 1 and 14 ± 1.4 months respectively (p = 0.3) whereas in peritonitis free patients it was 15 ± 1.4 months in CAPD and 23 ± 3.1 months in APD (p = 0.025). APD had lower incidence rate of peritonitis than CAPD. Patient survival was better in APD than CAPD in peritonitis free patients but was similar in patients who had peritonitis.

  3. Equilibrium paradigm for field-reversed configurations and application to experiments

    International Nuclear Information System (INIS)

    Steinhauer, Loren C.; Intrator, T. P.

    2009-01-01

    Fresh insights on field-reversed configurations (FRCs) are incorporated in a new paradigm for equilibria. In particular four new or unappreciated properties are accounted for: an empirically based scrape-off layer thickness; a new, more accurate axial force balance relation; viscous force regularity at the O-point; and the broken-surface effect. The new paradigm corrects glaring defects of previous models (rigid rotor, Hill's vortex). Further, the new paradigm is simple enough to be easily used as an interpretive tool despite the limited data suite in most experiments. It is applied to the newly enhanced FRC data compendium, a database of 69 records from 15 facilities. Several important observations and corrections on the previous understanding of FRCs follow, three of which stand out. (1) The traditional axial force balance ('average-β' relation) gives an inaccurate scaling with the separatrix-to-wall radius ratio. (2) The improved equilibrium paradigm yields separatrix particle transport rates of 3-5 m 2 /s for 'best confinement' examples; this is a factor of three lower than crude 'bulk' estimates commonly used. (3) The transport compared to the Bohm rate shows a great deal of scatter (40% scatter/mean ratio), i.e., 'Bohm' is not a useful representation for transport scaling.

  4. Electrical characteristics of TIG arcs in argon from non-equilibrium modelling and experiment

    Science.gov (United States)

    Baeva, Margarita; Uhrlandt, Dirk; Siewert, Erwan

    2016-09-01

    Electric arcs are widely used in industrial processes so that a thorough understanding of the arc characteristics is highly important to industrial research and development. TIG welding arcs operated with pointed electrodes made of tungsten, doped with cerium oxide, have been studied in order to analyze in detail the electric field and the arc voltage. Newly developed non-equilibrium model of the arc is based on a complete diffusion treatment of particle fluxes, a generalized form of Ohm's law, and boundary conditions accounting for the space-charge sheaths within the magneto-hydrodynamic approach. Experiments have been carried out for electric currents in the range 5-200 A. The electric arc has been initiated between a WC20 cathode and a water-cooled copper plate placed 0.8 mm from each other. The arc length has been continuously increased by 0.1 mm up to 15 mm and the arc voltage has been simultaneously recorded. Modelling and experimental results will be presented and discussed.

  5. Peritoneal Dialysis in Western Countries.

    Science.gov (United States)

    Struijk, Dirk G

    2015-12-01

    Peritoneal dialysis (PD) for the treatment of end-stage renal failure was introduced in the 1960s. Nowadays it has evolved to an established therapy that is complementary to hemodialysis (HD), representing 11% of all patients treated worldwide with dialysis. Despite good clinical outcomes and similar results in patient survival between PD and HD, the penetration of PD is decreasing in the Western world. First the major events in the history of the development of PD are described. Then important insights into the physiology of peritoneal transport are discussed and linked to the changes in time observed in biopsies of the peritoneal membrane. Furthermore, the developments in peritoneal access, more biocompatible dialysate solutions, automated PD at home, the establishment of parameters for dialysis adequacy and strategies to prevent infectious complications are mentioned. Finally non-medical issues responsible for the declining penetration in the Western world are analyzed. Only after introduction of the concept of continuous ambulatory PD by Moncrief and Popovich has this treatment evolved in time to a renal replacement therapy. Of all structures present in the peritoneal membrane, the capillary endothelium offers the rate-limiting hindrance for solute and water transport for the diffusive and convective transport of solutes and osmosis. The functional and anatomical changes in the peritoneal membrane in time can be monitored by the peritoneal equilibrium test. Peritonitis incidence decreased by introduction of the Y-set and prophylaxis using mupirocin on the exit site. The decrease in the proportion of patients treated with PD in the Western world can be explained by non-medical issues such as inadequate predialysis patient education, physician experience and training, ease of HD initiation, overcapacity of in-center HD, lack of adequate infrastructure for PD treatment, costs and reimbursement issues of the treatment. (1) PD is cheaper than HD and provides a

  6. Utilization of a Microcomputer for the Study of an Iodine Oxidation and Equilibrium Reaction: A Physical Chemistry Experiment.

    Science.gov (United States)

    Julien, L. M.

    1984-01-01

    Describes a physical chemistry experiment which incorporates the use of a microcomputer to enhance understanding of combined kinetic and equilibrium phenomena, to increase experimental capabilities when working with large numbers of students and limited equipment, and for the student to develop a better understanding of experimental design. (JN)

  7. Peritonitis in children with automated peritoneal dialysis: a single-center study of a 10-year experience.

    Science.gov (United States)

    Dotis, John; Myserlis, Pavlos; Printza, Nikoleta; Stabouli, Stella; Gkogka, Chrysa; Pavlaki, Antigoni; Papachristou, Fotios

    2016-08-01

    Peritoneal dialysis (PD) constitutes the preferred dialysis modality for children requiring renal replacement therapy with peritonitis being one of the most common complications of PD. This study was performed to evaluate the epidemiology, microbiology, and outcomes of PD-associated peritonitis in Greek children for a 10-year period. A total of 27 patients (16 males) with a mean age 121.8 ± 57.2 months were retrospective analyzed. Patients were on PD therapy for a mean duration of 45.2 ± 26.1 months. We found 23 episodes of PD-associated peritonitis occurred in 9 out of 27 patients (0.23 episodes/patient-year), with four patients experienced two or more peritonitis episodes. Gram-positive bacteria were responsible for 15 (65.2%) peritonitis episodes, with Staphylococcus aureus being the predominant specie isolated in 30.4% of cases. A total of seven episodes of exit-site infections (ESIs) were identified in five patients (0.069 episodes/patient-year) with the most common bacteria isolated being S. aureus (57.4%). Initial antibiotic treatment included intraperitoneal vancomycin plus ceftazidime in the majority of cases (82.6%). At the end of study, 12 (44.4%) patients remained on PD, 11 (41.8%) underwent renal transplantation, 2 (7.4%) shifted to hemodialysis and unfortunately, two patients (7.4%) died. Conclusively, our study revealed a noticeable low peritonitis and ESIs rate as compared to international data and represents the first evaluation of the characteristics and outcomes of peritonitis in the Greek pediatric PD population.

  8. Feasibility of Urgent-Start Peritoneal Dialysis in Older Patients with End-Stage Renal Disease: A Single-Center Experience.

    Science.gov (United States)

    Jin, Haijiao; Ni, Zhaohui; Mou, Shan; Lu, Renhua; Fang, Wei; Huang, Jiaying; Hu, Chunhua; Zhang, Haifen; Yan, Hao; Li, Zhenyuan; Yu, Zanzhe

    2018-01-01

    Patients with end-stage renal disease (ESRD) frequently require urgent-start dialysis. Recent evidence suggests that peritoneal dialysis (PD) might be a feasible alternative to hemodialysis (HD) in these patients, including in older patients. This retrospective study enrolled patients aged > 65 years with ESRD who underwent urgent dialysis without functional vascular access or PD catheter at a single center, from January 2011 to December 2014. Patients were grouped based on their dialysis modality (PD or HD). Patients unable to tolerate PD catheter insertion or wait for PD were excluded. Each patient was followed for at least 30 days after catheter insertion. Short-term (30-day) dialysis-related complications and patient survival were compared between the 2 groups. A total of 94 patients were enrolled, including 53 (56.4%) who underwent PD. The incidence of dialysis-related complications during the first 30 days was significantly lower in PD compared with HD patients (3 [5.7%] vs 10 [24.4%], p = 0.009). Logistic regression identified urgent-start HD as an independent risk factor for dialysis-related complications compared with urgent-start PD (odds ratio 4.760 [1.183 - 19.147], p = 0.028). The 6-, 12-, 24-, and 36-month survival rates in the PD and HD groups were 92.3% vs 94.6%, 82.4% vs 81.3%, 75.7% vs 74.2%, and 69.5% vs 60.6%, respectively, with no significant differences between the groups (log-rank = 0.011, p = 0.915). Urgent-start PD was associated with fewer short-term dialysis-related complications and similar survival to urgent-start HD in older patients with ESRD. Peritoneal dialysis may thus be a safe and effective dialysis modality for older ESRD patients requiring urgent dialysis. Copyright © 2018 International Society for Peritoneal Dialysis.

  9. Non-equilibrium between ions and electrons inside hot spots from National Ignition Facility experiments

    Directory of Open Access Journals (Sweden)

    Zhengfeng Fan

    2017-01-01

    Full Text Available The non-equilibrium between ions and electrons in the hot spot can relax the ignition conditions in inertial confinement fusion [Fan et al., Phys. Plasmas 23, 010703 (2016], and obvious ion-electron non-equilibrium could be observed by our simulations of high-foot implosions when the ion-electron relaxation is enlarged by a factor of 2. On the other hand, in many shots of high-foot implosions on the National Ignition Facility, the observed X-ray enhancement factors due to ablator mixing into the hot spot are less than unity assuming electrons and ions have the same temperature [Meezan et al., Phys. Plasmas 22, 062703 (2015], which is not self-consistent because it can lead to negative ablator mixing into the hot spot. Actually, this non-consistency implies ion-electron non-equilibrium within the hot spot. From our study, we can infer that ion-electron non-equilibrium exists in high-foot implosions and the ion temperature could be ∼9% larger than the equilibrium temperature in some NIF shots.

  10. An experiment on radioactive equilibrium and its modelling using the ‘radioactive dice’ approach

    Science.gov (United States)

    Santostasi, Davide; Malgieri, Massimiliano; Montagna, Paolo; Vitulo, Paolo

    2017-07-01

    In this article we describe an educational activity on radioactive equilibrium we performed with secondary school students (17-18 years old) in the context of a vocational guidance stage for talented students at the Department of Physics of the University of Pavia. Radioactive equilibrium is investigated experimentally by having students measure the activity of 214Bi from two different samples, obtained using different preparation procedures from an uraniferous rock. Students are guided in understanding the mathematical structure of radioactive equilibrium through a modelling activity in two parts. Before the lab measurements, a dice game, which extends the traditional ‘radioactive dice’ activity to the case of a chain of two decaying nuclides, is performed by students divided into small groups. At the end of the laboratory work, students design and run a simple spreadsheet simulation modelling the same basic radioactive chain with user defined decay constants. By setting the constants to realistic values corresponding to nuclides of the uranium decay chain, students can deepen their understanding of the meaning of the experimental data, and also explore the difference between cases of non-equilibrium, transient and secular equilibrium.

  11. Modeling, measurement, and 3-D equilibrium reconstruction of the bootstrap current in the Helically Symmetric Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt, J. C.; Talmadge, J. N.; Anderson, D. T. [Department of Electrical and Computer Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); Hanson, J. D. [Department of Physics, Auburn University, Auburn, Alabama 36849 (United States)

    2014-09-15

    The bootstrap current for three electron cyclotron resonance heated plasma scenarios in a quasihelically symmetric stellarator (the Helically Symmetric Experiment) are analyzed and compared to a neoclassical transport code PENTA. The three conditions correspond to 50 kW input power with a resonance that is off-axis, 50 kW on-axis heating and 100 kW on-axis heating. When the heating location was moved from off-axis to on-axis with 50 kW heating power, the stored energy and the extrapolated steady-state current were both observed to increase. When the on-axis heating power was increased from 50 kW to 100 kW, the stored energy continued to increase while the bootstrap current slightly decreased. This trend is qualitatively in agreement with the calculations which indicate that a large positive electric field for the 100 kW case was driving the current negative in a small region close to the magnetic axis and accounting for the decrease in the total integrated current. This trend in the calculations is only observed to occur when momentum conservation between particle species is included. Without momentum conservation, the calculated bootstrap current increases monotonically. We show that the magnitude of the bootstrap current as calculated by PENTA agrees better with the experiment when momentum conservation between plasma species is included in the calculation. The total current was observed in all cases to flow in a direction to unwind the transform, unlike in a tokamak in which the bootstrap current adds to the transform. The 3-D inductive response of the plasma is simulated to predict the evolution of the current profile during the discharge. The 3-D equilibrium reconstruction code V3FIT is used to reconstruct profiles of the plasma pressure and current constrained by measurements with a set of magnetic diagnostics. The reconstructed profiles are consistent with the measured plasma pressure profile and the simulated current profile when the

  12. Leaching from MSWI bottom ash: Evaluation of non-equilibrium in column percolation experiments

    DEFF Research Database (Denmark)

    Hyks, Jiri; Astrup, Thomas; Christensen, Thomas Højlund

    2009-01-01

    -equilibrium-induced changes in the solubility control. Despite both physical and chemical non-equilibrium, the Columns were found to provide adequate information for readily soluble compounds (i.e., Na, Cl-, and K) and solubility-controlled elements (i.e., Ca, SO42-, Ba, Si, Al, Zn, and Pb). The leaching Of Cu and Ni...... was shown to depend strongly on DOC leaching, which was likely affected by physical non-equilibrium during flow interruptions. Consequently, the leaching of Cu and Ni in the undisturbed Columns Was shown to be by about one order of magnitude lower compared with the interrupted column. The results indicate...... in turn appeared to be controlled by diffusion from the stagnant zone: no Mo controlling minerals were predicted by the geochemical modeling....

  13. Non-equilibrium between ions and electrons inside hot spots from National Ignition Facility experiments

    OpenAIRE

    Zhengfeng Fan; Yuanyuan Liu; Bin Liu; Chengxin Yu; Ke Lan; Jie Liu

    2017-01-01

    The non-equilibrium between ions and electrons in the hot spot can relax the ignition conditions in inertial confinement fusion [Fan et al., Phys. Plasmas 23, 010703 (2016)], and obvious ion-electron non-equilibrium could be observed by our simulations of high-foot implosions when the ion-electron relaxation is enlarged by a factor of 2. On the other hand, in many shots of high-foot implosions on the National Ignition Facility, the observed X-ray enhancement factors due to ablator mixing into...

  14. Phase equilibrium of North Sea oils with polar chemicals: Experiments and CPA modeling

    DEFF Research Database (Denmark)

    Frost, Michael Grynnerup; Kontogeorgis, Georgios M.; von Solms, Nicolas

    2016-01-01

    This work consists of a combined experimental and modeling study for oil - MEG - water systems, of relevance to petroleum applications. We present new experimental liquid-liquid equilibrium data for the mutual solubility of two North Sea oils + MEG and North Sea oils + MEG + water systems...

  15. Pattern of causative microorgansims in catheter related blood stream infections in dialysis patients: experience from Saudi Arabia

    International Nuclear Information System (INIS)

    Mohsin, B.

    2017-01-01

    Catheter related blood stream infections (CRBSI) are the leading cause of morbidity in HD patients. The majority of these infections relate to haemodialysis catheters. There is a paucity of local data on microbial agents responsible for CRBSI in our region. This prompted our study. Methods: This Prospective observatory survey was conducted in Department of Nephrology, King Fahd Hospital, Hofuf KSA from Nov 2014 to Jan 2017 (26 months). It was performed on dialysis patients with HD catheters who developed features of CRBSI. Blood cultures were taken from the patient and cultured microorganisms were observed and stratified according to type and prevalence in relation to age gender and comorbidities. Results: There were 210 distinct episodes of CRBSI. 61.5% (n=129) were due to gram negative microorganisms and 38.5% (n=81) were due to Gram positive microorganism. Fifty-three events were due to Coagulase Negative Staphylococcus aureus. Enterobacter cloachae accounted for 28 events. Pseudomonas 19 events, enterococcus faecalis 13, Klebsiella 11, Acinitobacter accounted for 8 events. CRBSI was observed more frequently in males (n=136), diabetics (n=113) and in age 40 years+-19 years(n=97). Conclusion: Gram negative microorganisms were more commonly responsible for CRBSI in our settings. Enterobacter cloachae was most common gram-negative microorganism responsible for CRBSI, a finding not observed in other studies. There was significant predisposition to diabetics, male gender and middle age group. We need further studies to observe antibiotics sensitivity of microorganisms so that we can standardize empirical antibiotics in cases of CRBSI. (author)

  16. Advances in peritoneal dialysis

    NARCIS (Netherlands)

    Krediet, R. T.

    2007-01-01

    New peritoneal dialysis (PD) patients have a better survival than new haemodialysis (HD) patients in the first years on dialysis. During long-term treatment, this changes into a survival advantage for HD. The superior initial survival on PD is related to a better preservation of residual renal

  17. Expansion dynamics and equilibrium conditions in a laser ablation plume of lithium: Modeling and experiment

    International Nuclear Information System (INIS)

    Stapleton, M.W.; McKiernan, A.P.; Mosnier, J.-P.

    2005-01-01

    The gas dynamics and atomic kinetics of a laser ablation plume of lithium, expanding adiabatically in vacuum, are included in a numerical model, using isothermal and isentropic self-similar analytical solutions and steady-state collisional radiative equations, respectively. Measurements of plume expansion dynamics using ultrafast imaging for various laser wavelengths (266-1064 nm), fluences (2-6.5 J cm -2 ), and spot sizes (50-1000 μm) are performed to provide input parameters for the model and, thereby, study the influence of laser spot size, wavelength, and fluence, respectively, on both the plume expansion dynamics and atomic kinetics. Target recoil pressure, which clearly affects plume dynamics, is included in the model. The effects of laser wavelength and spot size on plume dynamics are discussed in terms of plasma absorption of laser light. A transition from isothermal to isentropic behavior for spot sizes greater than 50 μm is clearly evidenced. Equilibrium conditions are found to exist only up to 300 ns after the plume creation, while complete local thermodynamic equilibrium is found to be confined to the very early parts of the expansion

  18. Amyloidosis associated with dialysis

    International Nuclear Information System (INIS)

    Schadmand, S.; Klose, K.J.; Wandel, E.

    1991-01-01

    Amongst the complications of dialysis, amyloid osteopathy is getting increasingly significant. It is due to deposition of β2-microglobulin. To determine the incidence and time of development of this complication, the skeletal radiographs of 185 patients undergoing dialysis, some for up to ten years, were analysed retrospectively. In about 10% of patients, the presence of β2-microglobulin osteopathy may be expected. The radiological features, sites of predilection and differential diagnosis of amyloid osteopathy and of other skeletal changes due to dialysis are discussed. (orig.) [de

  19. Non-machinery dialysis that achieves blood purification therapy without using full-scale dialysis machines.

    Science.gov (United States)

    Abe, Takaya; Onoda, Mistutaka; Matsuura, Tomohiko; Sugimura, Jun; Obara, Wataru; Sato, Toshiya; Takahashi, Mihoko; Chiba, Kenta; Abe, Tomiya

    2017-09-01

    An electrical or water supply and a blood purification machine are required for renal replacement therapy. There is a possibility that acute kidney injury can occur in large numbers and on a wide scale in the case of a massive earthquake, and there is the potential risk that the current supply will be unable to cope with acute kidney injury cases. However, non-machinery dialysis requires exclusive circuits and has the characteristic of not requiring the full-scale dialysis machines. We performed perfusion experiments that used non-machinery dialysis and recent blood purification machines in 30-min intervals, and the effectiveness of non-machinery dialysis was evaluated by the assessing the removal efficiency of potassium, which causes lethal arrhythmia during acute kidney injury. The non-machinery dialysis potassium removal rate was at the same level as continuous blood purification machines with a dialysate flow rate of 5 L/h after 15 min and continuous blood purification machines with a dialysate flow rate of 3 L/h after 30 min. Non-machinery dialysis required an exclusive dialysate circuit, the frequent need to replace bags, and new dialysate exchanged once every 30 min. However, it can be seen as an effective renal replacement therapy for crush-related acute kidney injury patients, even in locations or facilities not having the full-scale dialysis machines.

  20. Peritoneal Dialysis in Children*

    African Journals Online (AJOL)

    1971-06-02

    Jun 2, 1971 ... efficiency due to vasodilatation of the peritoneal vessels.' DIALYSIS ... osmotic load in the face of a decreasing blood urea and may thus help ... infection, heart failure, sodium and volume de- depletion; ..... around the catheter.

  1. Dialysis Extraction for Chromatography

    Science.gov (United States)

    Jahnsen, V. J.

    1985-01-01

    Chromatographic-sample pretreatment by dialysis detects traces of organic contaminants in water samples analyzed in field with minimal analysis equipment and minimal quantities of solvent. Technique also of value wherever aqueous sample and solvent must not make direct contact.

  2. Dialysis Facility Compare Data

    Data.gov (United States)

    U.S. Department of Health & Human Services — These are the official datasets used on the Medicare.gov Dialysis Facility Compare Website provided by the Centers for Medicare and Medicaid Services. These data...

  3. Your Dialysis Care Team

    Science.gov (United States)

    ... A to Z Health Guide Your Dialysis Care Team Tweet Share Print Email Good health care is ... dialyzers (artificial kidneys) for reuse. Vascular Access Care Team If you are a hemodialysis patient, another group ...

  4. Dialysis and contrast media

    International Nuclear Information System (INIS)

    Morcos, Sameh K.; Thomsen, Henrik S.; Webb, Judith A.W.

    2002-01-01

    In a previous survey we revealed uncertainty among responders about (a) whether or not to perform hemodialysis in patients with severely reduced renal function who had received contrast medium; and (b) when to perform hemodialysis in patients on regular treatment with hemodialysis or continuous ambulatory dialysis who received contrast medium. Therefore, the Contrast Media Safety Committee of The European Society of Urogenital Radiology decided to review the literature and to issue guidelines. The committee performed a Medline search. Based on this, a report and guidelines were prepared. The report was discussed at the Ninth European Symposium on Urogenital Radiology in Genoa, Italy. Hemodialysis and peritoneal dialysis safely remove both iodinated and gadolinium-based contrast media. The effectiveness of hemodialysis depends on many factors including blood and dialysate flow rate, permeability of dialysis membrane, duration of hemodialysis and molecular size, protein binding, hydrophilicity, and electrical charge of the contrast medium. Generally, several hemodialysis sessions are needed to removal all contrast medium, whereas it takes 3 weeks for continuous ambulatory dialysis to remove the agent completely. There is no need to schedule the dialysis in relation to the injection of iodinated or MR contrast media or the injection of contrast agent in relation to the dialysis program. Hemodialysis does not protect poorly functioning kidneys against contrast-medium-induced nephrotoxicity. Simple guidelines are given. (orig.)

  5. Dialysis access, infections, and hospitalisations in unplanned dialysis start patients

    DEFF Research Database (Denmark)

    Machowska, Anna; Alscher, Mark Dominik; Vanga, Satyanarayana Reddy

    2017-01-01

    Introduction: Unplanned dialysis start (UPS) associates with worse clinical outcomes, higher utilisation of healthcare resources, lower chances to select dialysis modality and UPS patients typically commenced in-centre haemodialysis (HD) with central venous catheter (CVC). We evaluated patient ou...

  6. Phosphate control in dialysis

    Directory of Open Access Journals (Sweden)

    Cupisti A

    2013-10-01

    Full Text Available Adamasco Cupisti,1 Maurizio Gallieni,2 Maria Antonietta Rizzo,2 Stefania Caria,3 Mario Meola,4 Piergiorgio Bolasco31Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy; 2Nephrology and Dialysis Unit, San Carlo Borromeo Hospital, Milan, Italy; 3Territorial Department of Nephrology and Dialysis, ASL Cagliari, Italy; 4Sant'Anna School of Advanced Studies, University of Pisa, Pisa, ItalyAbstract: Prevention and correction of hyperphosphatemia is a major goal of chronic kidney disease–mineral and bone disorder (CKD–MBD management, achievable through avoidance of a positive phosphate balance. To this aim, optimal dialysis removal, careful use of phosphate binders, and dietary phosphate control are needed to optimize the control of phosphate balance in well-nourished patients on a standard three-times-a-week hemodialysis schedule. Using a mixed diffusive–convective hemodialysis tecniques, and increasing the number and/or the duration of dialysis tecniques are all measures able to enhance phosphorus (P mass removal through dialysis. However, dialytic removal does not equal the high P intake linked to the high dietary protein requirement of dialysis patients; hence, the use of intestinal P binders is mandatory to reduce P net intestinal absorption. Unfortunately, even a large dose of P binders is able to bind approximately 200–300 mg of P on a daily basis, so it is evident that their efficacy is limited in the case of an uncontrolled dietary P load. Hence, limitation of dietary P intake is needed to reach the goal of neutral phosphate balance in dialysis, coupled to an adequate protein intake. To this aim, patients should be informed and educated to avoid foods that are naturally rich in phosphate and also processed food with P-containing preservatives. In addition, patients should preferentially choose food with a low P-to-protein ratio. For example, patients could choose egg white or protein from a vegetable source

  7. Osteoarthropathy in dialysis amyloidosis

    International Nuclear Information System (INIS)

    Baldrati, L.; Feletti, C.; Capponcini, C.; Docci, D.; Rocchi, A.; Balbi, B.; Bonsanto, R.; Mughetti, M.; Pasini, A.

    1991-01-01

    Many long-term (>60 months) hemodialysis patients develop a severe osteoarticular disease, called 'dialysis arthropathy', which is characterized by the deposition in bone and synovia of a new type of amyloid made mainly of β 2 -microglobulin. In the present study, 31 patients (17 males, 14 females; age 54.1±13 years) undergoing chronic hemodialysis arthropathy by means of clinics and of radiological investigations (conventional radiography and computed tomography). Sixteen patients (51.6%) had radiographic evidence of dialysis arthropathy: geodes (shoulders, 12 cases; wrists, 11; hips, 2; knees, 2) and/or destructive arthropathies (cervical spine, 13 cases; dorsolumbar spine, 2; hands, 2; hips, 1). Within 24 months, these lesions were found to progress slowly in the majoriry of cases. In the diagnostic process, CT should be employed in the study of spine, shoulders and hips when the lesions have not been sufficiently demonstrated by conventional radiography in the presence of evident clinical signs. Patients with dialysis arthropathy had undergone dialysis for longer periods than those without it (p<0.005) and showed a significantly higher incidence of both carpal tunnel syndrome (p<0.0005) and shoulder pain (p<0.005). Our findings confirm the high incidence and clinical importance of dialysis arthropathy in long-term hemodialysis patients end the value of diagnostic imaging in screening such patients for those lesions

  8. Determination of tin equilibrium isotope fractionation factors from synchrotron radiation experiments

    NARCIS (Netherlands)

    Polyakov, VB; Mineev, SD; Clayton, RN; Hu, G; Mineev, KS

    2005-01-01

    A method of determination of the reduced isotopic partition function ratio (beta-factor) from the partial density of state (PDOS) obtained by inelastic nuclear resonant X-ray scattering (INRXS) in synchrotron radiation experiments has been established. The method has been demonstrated by the example

  9. "Ico-Alone" single nocturnal exchange to initiate peritoneal dialysis in patients with residual renal function-Five year, single centre experience

    Directory of Open Access Journals (Sweden)

    T Jeloka

    2013-01-01

    Full Text Available We analyzed the outcome of incremental dialysis with single nocturnal icodextrin exchange peritoneal dialysis (PD as the initial treatment for end-stage kidney failure in patients who have significant residual renal function. All adult patients opting for PD as renal replacement therapy, having residual renal function, and urinary KT/V of 1.0 were offered incremental dialysis with single nocturnal icodextrin exchange as initial treatment. Adequacy of dialysis was calculated at 1, 3, and 6 months and then 6 monthly. Patients were shifted to conventional PD if short of adequacy or if clinically indicated. Median period on "Ico-alone," peritonitis, exit site infection rates, and patient survival, while on this protocol, were calculated. These outcomes were compared with the cohort of contemporary patients on conventional PD. Thirteen patients were initiated on "Ico-alone" dialysis between October 2006 and October 2011. The baseline characteristics were similar when compared with cohort of conventional PD patients, except urine volume, which was more in "Ico-alone" group (1265 ± 316 vs. 551 ± 504, P = 0.000. Total KT/V at 3 months (1.63 ± 0.6 vs. 1.7 ± 0.2, P = 0.6 and at 1 year (1.64 ± 0.5 vs. 1.53 ± 0.3, P = 0.6 was similar to the cohort of conventional PD patients. Median period on "Ico-alone" was 9.6 months. Peritonitis rate was 1 episode in 56.22 vs 25.29 patient-months and exit site infection was 1 episode in 56.2 vs 189.71 patient-months in "Ico-alone" and conventional group, respectively. Patient survival was 42.84 months in "Ico-alone′ vs 25.29 months in conventional dialysis ( P = 0.01. In conclusion, single icodextrin exchange offers adequate dialysis in patients with residual renal function (KT/V = 1 for a median period of 9 months.

  10. Filtering Dialysis Myths from Facts

    Science.gov (United States)

    ... to work. Fact: Many dialysis patients continue to work, go to school, or volunteer . Some take time off when they first start dialysis treatment and back to work or school after they have gotten used to ...

  11. Remote Patient Management for Home Dialysis Patients

    Directory of Open Access Journals (Sweden)

    Eric L. Wallace

    2017-11-01

    Full Text Available Remote patient management (RPM offers renal health care providers and patients with end-stage kidney disease opportunities to embrace home dialysis therapies with greater confidence and the potential to obtain better clinical outcomes. Barriers and evidence required to increase adoption of RPM by the nephrology community need to be clearly defined. Ten health care providers from specialties including nephrology, cardiology, pediatrics, epidemiology, nursing, and health informatics with experience in home dialysis and the use of RPM systems gathered in Vienna, Austria to discuss opportunities for, barriers to, and system requirements of RPM as it applies to the home dialysis patient. Although improved outcomes and cost-effectiveness of RPM have been demonstrated in patients with diabetes mellitus and heart disease, only observational data on RPM have been gathered in patients on dialysis. The current review focused on RPM systems currently in use, on how RPM should be integrated into future care, and on the evidence needed for optimized implementation to improve clinical and economic outcomes. Randomized controlled trials and/or large observational studies could inform the most effective and economical use of RPM in home dialysis. These studies are needed to establish the value of existing and/or future RPM models among patients, policy makers, and health care providers.

  12. Equilibrium and transient conductivity for gadolinium-doped ceria under large perturbations: I. Experiments

    DEFF Research Database (Denmark)

    Ricote, Sandrine; Zhu, Huayang; Coors, W. Grover

    2014-01-01

    (97% O2, 3% H2O) and vice versa reveal great asymmetries in relaxation times. Virtually instantaneous relaxations are observed in the first case, while the oxidizing-to-reducing relaxations take as long as 0.5h. This paper reports conductivity relaxations with over 20 orders of magnitude in the gas......-phase oxygen partial pressure. Models and experiments are used to show that the observed asymmetries cannot be explained by electrode defects or two-dimensional end effects. The companion paper develops a Nernst–Planck–Poisson model to assist the quantitative interpretation of the measurements reported...

  13. Equilibrium and non-equilibrium controls on the abundances of clumped isotopologues of methane during thermogenic formation in laboratory experiments: Implications for the chemistry of pyrolysis and the origins of natural gases

    Science.gov (United States)

    Shuai, Yanhua; Douglas, Peter M.J.; Zhang, Shuichang; Stolper, Daniel A.; Ellis, Geoffrey S.; Lawson, Michael; Lewan, Michael; Formolo, Michael; Mi, Jingkui; He, Kun; Hu, Guoyi; Eiler, John M.

    2018-01-01

    Multiply isotopically substituted molecules (‘clumped’ isotopologues) can be used as geothermometers because their proportions at isotopic equilibrium relative to a random distribution of isotopes amongst all isotopologues are functions of temperature. This has allowed measurements of clumped-isotope abundances to be used to constrain formation temperatures of several natural materials. However, kinetic processes during generation, modification, or transport of natural materials can also affect their clumped-isotope compositions. Herein, we show that methane generated experimentally by closed-system hydrous pyrolysis of shale or nonhydrous pyrolysis of coal yields clumped-isotope compositions consistent with an equilibrium distribution of isotopologues under some experimental conditions (temperature–time conditions corresponding to ‘low,’ ‘mature,’ and ‘over-mature’ stages of catagenesis), but can have non-equilibrium (i.e., kinetically controlled) distributions under other experimental conditions (‘high’ to ‘over-mature’ stages), particularly for pyrolysis of coal. Non-equilibrium compositions, when present, lead the measured proportions of clumped species to be lower than expected for equilibrium at the experimental temperature, and in some cases to be lower than a random distribution of isotopes (i.e., negative Δ18 values). We propose that the consistency with equilibrium for methane formed by relatively low temperature pyrolysis reflects local reversibility of isotope exchange reactions involving a reactant or transition state species during demethylation of one or more components of kerogen. Non-equilibrium clumped-isotope compositions occur under conditions where ‘secondary’ cracking of retained oil in shale or wet gas hydrocarbons (C2-5, especially ethane) in coal is prominent. We suggest these non-equilibrium isotopic compositions are the result of the expression of kinetic isotope effects during the irreversible generation

  14. Equilibrium and non-equilibrium controls on the abundances of clumped isotopologues of methane during thermogenic formation in laboratory experiments: Implications for the chemistry of pyrolysis and the origins of natural gases

    Science.gov (United States)

    Shuai, Yanhua; Douglas, Peter M. J.; Zhang, Shuichang; Stolper, Daniel A.; Ellis, Geoffrey S.; Lawson, Michael; Lewan, Michael D.; Formolo, Michael; Mi, Jingkui; He, Kun; Hu, Guoyi; Eiler, John M.

    2018-02-01

    Multiply isotopically substituted molecules ('clumped' isotopologues) can be used as geothermometers because their proportions at isotopic equilibrium relative to a random distribution of isotopes amongst all isotopologues are functions of temperature. This has allowed measurements of clumped-isotope abundances to be used to constrain formation temperatures of several natural materials. However, kinetic processes during generation, modification, or transport of natural materials can also affect their clumped-isotope compositions. Herein, we show that methane generated experimentally by closed-system hydrous pyrolysis of shale or nonhydrous pyrolysis of coal yields clumped-isotope compositions consistent with an equilibrium distribution of isotopologues under some experimental conditions (temperature-time conditions corresponding to 'low,' 'mature,' and 'over-mature' stages of catagenesis), but can have non-equilibrium (i.e., kinetically controlled) distributions under other experimental conditions ('high' to 'over-mature' stages), particularly for pyrolysis of coal. Non-equilibrium compositions, when present, lead the measured proportions of clumped species to be lower than expected for equilibrium at the experimental temperature, and in some cases to be lower than a random distribution of isotopes (i.e., negative Δ18 values). We propose that the consistency with equilibrium for methane formed by relatively low temperature pyrolysis reflects local reversibility of isotope exchange reactions involving a reactant or transition state species during demethylation of one or more components of kerogen. Non-equilibrium clumped-isotope compositions occur under conditions where 'secondary' cracking of retained oil in shale or wet gas hydrocarbons (C2-5, especially ethane) in coal is prominent. We suggest these non-equilibrium isotopic compositions are the result of the expression of kinetic isotope effects during the irreversible generation of methane from an alkyl

  15. The Toshiba Blow-Down MHD Test Facility, and Experiments on Non-Equilibrium Ionization

    International Nuclear Information System (INIS)

    Yamamoto, Y.; Ogiwara, H.; Shioda, S.; Miyata, M.; Goto, M.; Kasahara, E.

    1968-01-01

    The Toshiba blow-down MHD test facility, which was constructed in 1966 and has operated successfully in many experiments, is described. Operating conditions achieved are: the working gas is helium seeded with potassium, the maximum mass flow being 80 g/sec, the maximum seed fraction 0.1%; the gas static lies between temperature 1200 and 1700°K, the static pressure between 2.0 ∼ 1.2 atm, the velocity of gas in the generator channel between 1000 and 200 m/sec; the duration is up to 30 sec; the magnetic field is 2.7 T; the impurity of working gas is below 150 ppm. (author)

  16. Experimental studies of equilibrium in the toroidal Extrap T1 experiment

    International Nuclear Information System (INIS)

    Drake, J.R.; Hedin, E.R.; Karlsson, P.; Jin Li; Saetherblom, H.E.

    1989-03-01

    Experimental studies of a toroidal, high-beta plasma discharge with a non-circular cross-section are described. In Extrap T1, four toroidal, current-carrying rings outside the plasma discharge current channel produce a separatrix which bounds the plasma. Plasma currents of up to 40 kA are induced, operating with a toroidal field of up to 0.2 T. The major radius of the device is 0.45 m and the average minor radius of the current channel is about 40 mm. The discharge pulse is approximately 100 μsec long. For the discharges reported here, the peak current density on the discharge axis is about 9 MA/m 2 , which corresponds to an on-axis safety factor q o of about 0.1. The plasma density is in the range n ≅ 0.2 to 1 x 10 21 m -3 , and the electron temperature is in the range T e ≅ 10 to 30 eV. Magnetic flux plots of the experiment have been studied using magnetic probes and current and pressure profiles have been derived from the magnetic data

  17. Rapid separation of pure 144Ce fraction from fuel dissolver solution for demonstration experiment on secular equilibrium

    International Nuclear Information System (INIS)

    Ashok Kumar, G.V.S.; Kumar, R.; Venkata Subramani, C.R.

    2015-01-01

    Radioactive equilibrium is a condition in which the activity ratio of parent to its daughter is maintained constant with time which occurs only when the parent half-life is greater than daughter half-life. It is transient equilibrium in the case of the ratio of their half-lives of parent to daughter being less than an order whereas it becomes secular equilibrium when it is more than an order. In the case of secular equilibrium, the ratio of the activities becomes unity whereas the same depends on the decay constants of the parent and daughter nuclide for the transient equilibrium. 144 Ce- 144 Pr pair is a good example for the demonstration of secular equilibrium

  18. Fall Back Equilibrium

    NARCIS (Netherlands)

    Kleppe, J.; Borm, P.E.M.; Hendrickx, R.L.P.

    2008-01-01

    Fall back equilibrium is a refinement of the Nash equilibrium concept. In the underly- ing thought experiment each player faces the possibility that, after all players decided on their action, his chosen action turns out to be blocked. Therefore, each player has to decide beforehand on a back-up

  19. Peritoneal Dialysis in Children*

    African Journals Online (AJOL)

    1971-06-02

    Jun 2, 1971 ... cellular fluid' into the peritoneal cavity allows both the removal of excess fluid ... occur. In adults the maximum peritoneal urea clearance is ob- tained with a dialysis ..... and Records. Pulse and respiration rates, temperature and blood .... diffusion of urea out of the brain cells, with consequent movement of ...

  20. Aliskiren prevents the toxic effects of peritoneal dialysis fluids during chronic dialysis in rats.

    Directory of Open Access Journals (Sweden)

    Juan Pérez-Martínez

    Full Text Available The benefits of long-term peritoneal dialysis (PD in patients with end-stage renal failure are short-lived due to structural and functional changes in the peritoneal membrane. In this report, we provide evidence for the in vitro and in vivo participation of the renin-angiotensin-aldosterone system (RAAS in the signaling pathway leading to peritoneal fibrosis during PD. Exposure to high-glucose PD fluids (PDFs increases damage and fibrosis markers in both isolated rat peritoneal mesothelial cells and in the peritoneum of rats after chronic dialysis. In both cases, the addition of the RAAS inhibitor aliskiren markedly improved damage and fibrosis markers, and prevented functional modifications in the peritoneal transport, as measured by the peritoneal equilibrium test. These data suggest that inhibition of the RAAS may be a novel way to improve the efficacy of PD by preventing inflammation and fibrosis following peritoneal exposure to high-glucose PDFs.

  1. Types of vicarious learning experienced by pre-dialysis patients

    OpenAIRE

    McCarthy, Kate; Sturt, Jackie; Adams, Ann

    2015-01-01

    Objective: Haemodialysis and peritoneal dialysis renal replacement treatment options are in clinical equipoise, although the cost of haemodialysis to the National Health Service is £16,411/patient/year greater than peritoneal dialysis. Treatment decision-making takes place during the pre-dialysis year when estimated glomerular filtration rate drops to between 15 and 30 mL/min/1.73 m2. Renal disease can be familial, and the majority of patients have considerable health service experience when ...

  2. Renal telemedicine through video-as-a-service delivered to patients on home dialysis: A qualitative study on the renal care team members' experience.

    Science.gov (United States)

    Ditchburn, Jae-Llane; Marshall, Alison

    2017-09-01

    The Lancashire Teaching Hospitals NHS Trust in the UK has been providing renal care through video-as-a-service (VAAS) to patients since 2013, with support from the North West NHS Shared Infrastructure Service, a collaborative team that supports information and communication technology use in the UK National Health Service. Renal telemedicine offered remotely to patients on home dialysis supports renal care through the provision of a live high-quality video link directly to unsupported patients undergoing haemodialysis at home. Home haemodialysis is known to provide benefits to patients, particularly in making them more independent. The use of a telemedicine video-link in Lancashire and South Cumbria, UK, further reduces patient dependence on the professional team. The purpose of this paper is to present the perspectives of the renal care team members using the renal telemedicine service to understand the perceived benefits and issues with the service. Ten semi-structured interviews with members of the renal care team (two renal specialists, one matron, two renal nurses, one business manager, one renal technical services manager, two IT technicians and one hardware maintenance technician) were conducted. Thematic analysis was undertaken to analyse the qualitative data. A range of incremental benefits to the renal team members were reported, including more efficient use of staff time, reduced travel, peace of mind and a strong sense of job satisfaction. Healthcare staff believed that remote renal care through video was useful, encouraged concordance and could nurture confidence in patients. Key technological issues and adjustments which would improve the renal telemedicine service were also identified. The impact of renal telemedicine was positive on the renal team members. The use of telemedicine has been demonstrated to make home dialysis delivery more efficient and safe. The learning from staff feedback could inform development of services elsewhere. © 2017

  3. Advancing non-equilibrium ARPES experiments by a 9.3 eV coherent ultrafast photon source

    Energy Technology Data Exchange (ETDEWEB)

    Cilento, F., E-mail: federico.cilento@elettra.eu [Elettra – Sincrotrone Trieste S.C.p.A., Strada Statale 14, km 163.5, Trieste 34149 (Italy); C.N.R. – I.O.M., Strada Statale 14, km 163.5, Trieste 34149 (Italy); Crepaldi, A. [Elettra – Sincrotrone Trieste S.C.p.A., Strada Statale 14, km 163.5, Trieste 34149 (Italy); Manzoni, G.; Sterzi, A. [Universitá degli Studi di Trieste, Via A. Valerio 2, Trieste 34127 (Italy); Zacchigna, M. [C.N.R. – I.O.M., Strada Statale 14, km 163.5, Trieste 34149 (Italy); Bugnon, Ph.; Berger, H. [Institute of Condensed Matter Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland); Parmigiani, F. [Elettra – Sincrotrone Trieste S.C.p.A., Strada Statale 14, km 163.5, Trieste 34149 (Italy); Universitá degli Studi di Trieste, Via A. Valerio 2, Trieste 34127 (Italy); International Faculty, University of Köln, 50937 Köln (Germany)

    2016-02-15

    The quest for investigating the non-equilibrium dynamics of the band structure of strongly-correlated materials over their entire Brillouin zone is a primary objective. However, the actual ultrafast UV light sources are not suitable for addressing several critical questions in the field. Here we report on a novel light source generating sub-250 fs, 9.3 eV photon energy light pulses at 250 kHz repetition rate, obtained via third-harmonic generation in Xe of frequency-doubled 50 fs laser pulses at 1.55 eV. By reporting the measured band dispersion of a Cu(111) crystal and the non-equilibrium dynamics of the Bi{sub 2}Se{sub 3} topological insulator, we prove that this source is suitable for studying the non-equilibrium dynamics of the entire Fermi surface of several complex materials, with high signal statistics and limited space-charge effect.

  4. Peritoneal Dialysis Dose and Adequacy

    Science.gov (United States)

    ... infused dialysis solution and how much urea and creatinine have entered into the solution during a 4-hour dwell. The peritoneal transport rate varies from person to person. People who have a high rate of transport absorb dextrose from the dialysis ...

  5. Peritoneal Dialysis in Western Countries

    NARCIS (Netherlands)

    Struijk, Dirk G.

    2015-01-01

    Peritoneal dialysis (PD) for the treatment of end-stage renal failure was introduced in the 1960s. Nowadays it has evolved to an established therapy that is complementary to hemodialysis (HD), representing 11% of all patients treated worldwide with dialysis. Despite good clinical outcomes and

  6. Metabolic alterations in dialysis patients

    NARCIS (Netherlands)

    Drechsler, Christiane

    2010-01-01

    Assessing metabolic risk in dialysis patients, three main aspects are important: a) the pathophysiologic effects of metabolic disturbances as known from the general population are unlikely to completely reverse once patients reach dialysis. b) Specific additional problems related to chronic kidney

  7. Effect of the quality of water used for dialysis on the efficacy of hemodialysis: A single-center experience from Morocco

    Directory of Open Access Journals (Sweden)

    I Akhmouch

    2011-01-01

    Full Text Available The quality of the water used for dialysis has been suggested as a factor causing inflammation in patients on hemodialysis (HD. We therefore conducted this study to identify the effect of quality of the water on nutritional state, inflammation and need for human recombinant erythropoietin (EPO in patients undergoing HD at Agadir, Morocco. This prospective study included patients on HD for at least one year. The water treatment was done according to the standard protocol, which was followed by additional enhancement of ultrafiltration using an additional polysulfone filter (diasafe, Fresenius, Bad Homburg, Germany before the dialyser. Water was monitored regularly during the study period to ensure acceptable levels of bacterial count as well as endotoxin levels. Various parameters including dry weight, systolic and diastolic blood pressure (PA before and after an HD session, need for human recombinant EPO, levels of hemoglobin (Hb, albumin, ferritin, C-reactive protein (CRP, and the dose of dialysis delivered (Kt/V were measured first at the beginning of the study and thereafter, in the third, sixth and 12 th months of the study. The study involved 47 patients, and after 12 months of the study, an improvement in median dry weight (1.2 kg, P = 0017 and a simultaneous median reduction of 20.7 IU/kg/week of EPO, with an in-crease of the median level of Hb, was noted. The results of our study suggest that by improving the biocompatibility of HD with the use of good quality water, patients acquire a better nutritional, inflammatory and hematologic status.

  8. Natural disasters and dialysis care in the Asia-Pacific.

    Science.gov (United States)

    Gray, Nicholas A; Wolley, Martin; Liew, Adrian; Nakayama, Masaaki

    2015-12-01

    The impact of natural disasters on the provision of dialysis services has received increased attention in the last decade following Hurricane Katrina devastating New Orleans in 2005. The Asia-Pacific is particularly vulnerable to earthquakes, tsunami, typhoons (also known as cyclones and hurricanes) or storms and flooding. These events can seriously interrupt provision of haemodialysis with adverse effects for patients including missed dialysis, increased hospitalization and post-traumatic stress disorder. Furthermore, haemodialysis patients may need to relocate and experience prolonged periods of displacement from family and social supports. In contrast to haemodialysis, most literature suggests peritoneal dialysis in a disaster situation is more easily managed and supported. It has become apparent that dialysis units and patients should be prepared for a disaster event and that appropriate planning will result in reduced confusion and adverse outcomes should a disaster occur. Numerous resources are now available to guide dialysis units, patients and staff in preparation for a possible disaster. This article will examine the disaster experiences of dialysis units in the Asia-Pacific, the impact on patients and staff, methods employed to manage during the disaster and suggested plans for reducing the impact of future disasters. © 2015 Asian Pacific Society of Nephrology.

  9. Peritoneal Dialysis in Asia.

    Science.gov (United States)

    Kwong, Vickie Wai-Ki; Li, Philip Kam-Tao

    2015-12-01

    There is a growing demand of dialysis in Asia for end-stage renal failure patients. Diabetes mellitus is the leading cause of end-stage renal failure in many countries in Asia. The growth of peritoneal dialysis (PD) in Asia is significant and seeing a good trend. With the enhanced practices of PD, the quality of care in PD in Asia is also improved. Overall, PD and hemodialysis (HD) are comparable in clinical outcome. There is a global trend in the reduction of peritonitis rates and Asian countries also witness such improvement. The socio-economic benefits of PD for end-stage renal failure patients in both urban and rural areas in the developed and developing regions of Asia are an important consideration. This can help to reduce the financial burden of renal failure in addressing the growing demand of patients on dialysis. Initiatives should be considered to further drive down the cost of PD in Asia. Growing demand for dialysis by an increasing number of end-stage renal failure patients requires the use of a cost-effective quality dialysis modality. PD is found to be comparable to HD in outcome and quality. In most countries in Asia, PD should be more cost-effective than HD. A 'PD-first' or a 'PD as first considered therapy' policy can be an overall strategy in many countries in Asia in managing renal failure patients, taking the examples of Hong Kong and Thailand. (1) PD is cheaper than HD and provides a better quality of life worldwide, but its prevalence is significantly lower than that of HD in all countries, with the exception of Hong Kong. Allowing reimbursement of PD but not HD has permitted to increase the use of PD over HD in many Asian countries like Hong Kong, Vietnam, Taiwan, Thailand, as well as in New Zealand and Australia over the last years. In the Western world, however, HD is still promoted, and the proportion of patients treated with PD decreases. Japan remains an exception in Asia where PD penetration is very low. Lack of adequate education of

  10. Local equilibrium

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1984-12-15

    From 3-6 September the First International Workshop on Local Equilibrium in Strong Interaction Physics took place in Bad-Honnef at the Physics Centre of the German Physical Society. A number of talks covered the experimental and theoretical investigation of the 'hotspots' effect, both in high energy particle physics and in intermediate energy nuclear physics.

  11. Strategic Equilibrium

    NARCIS (Netherlands)

    van Damme, E.E.C.

    2000-01-01

    An outcome in a noncooperative game is said to be self-enforcing, or a strategic equilibrium, if, whenever it is recommended to the players, no player has an incentive to deviate from it.This paper gives an overview of the concepts that have been proposed as formalizations of this requirement and of

  12. Maximin equilibrium

    NARCIS (Netherlands)

    Ismail, M.S.

    2014-01-01

    We introduce a new concept which extends von Neumann and Morgenstern's maximin strategy solution by incorporating `individual rationality' of the players. Maximin equilibrium, extending Nash's value approach, is based on the evaluation of the strategic uncertainty of the whole game. We show that

  13. Water-Permeable Dialysis Membranes for Multi-Layered Micro Dialysis System

    Directory of Open Access Journals (Sweden)

    Naoya eTo

    2015-06-01

    Full Text Available This paper presents the development of water-permeable dialysis membranes that are suitable for an implantable microdialysis system that does not use dialysis fluid. We developed a microdialysis system integrating microfluidic channels and nanoporous filtering membranes made of polyethersulfone (PES, aiming at a fully implantable system that drastically improves the quality of life of patients. Simplicity of the total system is crucial for the implantable dialysis system, where the pumps and storage tanks for the dialysis fluid pose problems. Hence, we focus on hemofiltration, which does not require the dialysis fluid but water-permeable membranes. We investigated the water-permeability of the PES membrane with respect to the concentrations of the PES, the additives, and the solvents in the casting solution. Sufficiently water-permeable membranes were found through in vitro experiments using whole bovine blood. The filtrate was verified to have the concentrations of low-molecular-weight molecules, such as sodium, potassium, urea, and creatinine, while proteins, such as albumin, were successfully blocked by the membrane. We conducted in vivo experiments using rats, where the system was connected to the femoral artery and jugular vein. The filtrate was successfully collected without any leakage of blood inside the system and it did not contain albumin but low-molecular-weight molecules whose concentrations were identical to those of the blood. The rat model with renal failure showed 100% increase of creatinine in 5 h, while rats connected to the system showed only a 7.4% increase, which verified the effectiveness of the proposed microdialysis system.

  14. Discovering a Change in Equilibrium Constant with Change in Ionic Strength: An Empirical Laboratory Experiment for General Chemistry

    Science.gov (United States)

    Stolzberg, Richard J.

    1999-05-01

    Students are challenged to investigate the hypothesis that an equilibrium constant, Kc, measured as a product and quotient of molar concentrations, is constant at constant temperature. Spectrophotometric measurements of absorbance of a solution of Fe3+(aq) and SCN-(aq) treated with different amounts of KNO3 are made to determine Kc for the formation of FeSCN2+(aq). Students observe a regular decrease in the value of Kc as the concentration of added KNO3 is increased.

  15. Peritoneal dialysis in Asia.

    Science.gov (United States)

    Cheng, I K

    1996-01-01

    The socioeconomic status of Asian countries is diverse, and government reimbursement policies for treatment of patients suffering from end-stage renal disease (ESRD) vary greatly from one country to another. Both of these factors have a major impact not only on the choice of treatment for ESRD but also on the utilization of peritoneal dialysis (PD) in this region. Based on the data collected from 11 representative Asian countries, several observations can be made. First, the treatment rates for ESRD in these countries correlated closely with their gross domestic product (GDP) per capita income. Second, the PD utilization rate appeared to have a biphasic relationship with the GDP per capita income and treatment rate, in that countries with the highest and the lowest treatment rates tended to have lower PD utilization rates, whereas countries with modest treatment rates tended to have higher PD utilization rates. The reason for low PD utilization in countries with the highest treatment rates differs from that in countries with low treatment rates. In the former, because of full government reimbursement, there is little physician incentive to introduce PD as an alternative form of ESRD treatment to in-center hemodialysis (HD), whereas in the latter, the complete lack of government reimbursement prevents the introduction of PD as a form of treatment. This pattern is likely to change in the future because, of the 11 countries surveyed, all except Thailand have recorded a growth rate which is higher for PD than HD over the last three years. The rate of utilization of different PD systems varies greatly among different Asian countries. Automated PD has yet to gain popularity in Asia. Conventional straight-line systems remain the dominant PD systems in use in Hong Kong, Korea, Thailand, and the Philippines, while in Malaysia and Singapore UV germicidal connection devices are most popular. However, in all these countries there has been a progressive shift over the last

  16. Role of regional anesthesia for placement of peritoneal dialysis catheter under ultrasound guidance: Our experience with 52 end-stage renal disease patients

    Directory of Open Access Journals (Sweden)

    Smaranjit Chatterjee

    2015-01-01

    Full Text Available Aim: The number of patients with end-stage renal disease (ESRD has shown a consistent rise in India in recent years. Continuous ambulatory peritoneal dialysis (CAPD remains one of the safe and effective forms of treatment. In this study, we have tried to assess the effectiveness of field block technique for analgesia during catheter placement surgery until 24 h postoperatively, also, if it can obviate the need for general anesthesia in these high-risk patients. Materials and Methods: We studied 52 ESRD patients from 2010 to 2012 who were posted for CAPD catheterization in the Department of Urology, Care Hospital, Hyderabad, India. Under ultrasound guidance, "unilateral posterior" and "unilateral subcostal" transversus abdominis plane block anesthesia were given for the placement of CAPD catheter. Patient′s intra-operative pain and post-operative pain were recorded with visual analog scores (VAS and analyzed. Results: All patients in our study belonged to American Society of Anesthesiologists category 2 or 3 with multiple co-morbidities. 41 out of 52 patients required no supplemental analgesia during the procedure; 8 patients needed additional infiltration of local anesthetic during skin incisions. Three patients required supplemental analgesia and were considered as failure. A VAS of two was noted in 30 patients and 1 in 19 Patients. No Patient had significant pain 24 h post operatively. No local complication was noted in any patient. Conclusion: CAPD Catheterization under regional field block remains safe and effective options for ESRD patients.

  17. What's the Deal with Dialysis?

    Science.gov (United States)

    ... Dialysis Work? Other Options Print Don't you love swimming in a cool, blue pool? Splashing around ... dialysate cleanses the blood and rebalances the blood's chemistry. After about an hour, the machine drains the ...

  18. Toward dialysis "a la carte".

    Science.gov (United States)

    Funck-Brentano, J L

    1987-12-01

    From the very beginning, the artificial kidney postponed the death of patients with end-stage renal failure. For years, owing to the performance of the machine, the patient was obliged to follow a severe diet in order to maintain good humoral and circulatory status. Now technological improvements allow "dialysis à la carte," whereby each individual achieves a better clinical status. The next step will be automation of the procedure to improve its security, mainly for dialysis performed at home.

  19. Sweatshop equilibrium

    OpenAIRE

    Chau, Nancy H.

    2009-01-01

    This paper presents a capability-augmented model of on the job search, in which sweatshop conditions stifle the capability of the working poor to search for a job while on the job. The augmented setting unveils a sweatshop equilibrium in an otherwise archetypal Burdett-Mortensen economy, and reconciles a number of oft noted yet perplexing features of sweatshop economies. We demonstrate existence of multiple rational expectation equilibria, graduation pathways out of sweatshops in complete abs...

  20. Comparison of survival between dialysis patients with incident high-flux hemodialysis versus on-line hemodiafiltration: A single center experience in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Mohamed Said Abdelsalam

    2018-01-01

    Full Text Available Conventional hemodialysis (HD is the most common treatment modality used for renal replacement therapy. The concept of HD is based on the diffusion of solutes across a semipermeable membrane. Hemofiltration (HF is based on convective transport of solutes; hemodiafiltration (HDF is based on combined convective and diffusive therapies. Data about survival benefit of on-line HDF (OL-HDF over high-flux HD (HF-HD is conflicting. We conducted this study to investigate if there is a survival difference between the two treatment modalities. This study is a retrospective, single-center study in which 78 patients were screened; 18 were excluded and 60 patients were analyzed. The study patients were aged 47.5 ± 20.7 years, 33 patients (55% were on HF-HD, and 27 patients (45% were on OL-HDF. A total of 24 patients (40% of both groups were diabetic and, the mean duration on dialysis was 43.5 ±21.3 months in the HF-HD group and 41.2 ± 22.0 months in the OL-HDF group. The mean substitution volume for OL-HDF was 22.3 ± 2.5 L. Survival was 73% [95%, confidence interval (CI 60–84] in the HF-HD group and 65% (95%, CI 54–75 in the OL-HDF group by the end of the study period. The unadjusted hazard ratio (HR with 95% CI comparing HF-HD to high-volume postdilution OL-HDF was 0.78 (0.10–5.6; P = 0.810. Kaplan–Meier analysis for patient survival over five years showed no significant difference between the two modalities. Prospective controlled trials with a larger number of patients will be needed to assess the long-term clinical outcome of postdilution OL-HDF over HF-HD.

  1. Predictors of Peritonitis and the Impact of Peritonitis on Clinical Outcomes of Continuous Ambulatory Peritoneal Dialysis Patients in Taiwan—10 Years’ Experience in a Single Center

    Science.gov (United States)

    Hsieh, Yao-Peng; Chang, Chia-Chu; Wen, Yao-Ko; Chiu, Ping-Fang; Yang, Yu

    2014-01-01

    ♦ Objective: Peritoneal dialysis (PD) has become more prevalent as a treatment modality for end-stage renal disease, and peritonitis remains one of its most devastating complications. The aim of the present investigation was to examine the frequency and predictors of peritonitis and the impact of peritonitis on clinical outcomes. ♦ Methods: Our retrospective observational cohort study enrolled 391 patients who had been treated with continuous ambulatory PD (CAPD) for at least 90 days. Relevant demographic, biochemical, and clinical data were collected for an analysis of CAPD-associated peritonitis, technique failure, drop-out from PD, and patient mortality. ♦ Results: The peritonitis rate was 0.196 episodes per patient-year. Older age (>65 years) was the only identified risk factor associated with peritonitis. A multivariate Cox regression model demonstrated that technique failure occurred more often in patients experiencing peritonitis than in those free of peritonitis (p peritonitis tended to survive longer than the group that was peritonitis-free (p = 0.11). After multivariate adjustment, the survival advantage reached significance (hazard ratio: 0.64; 95% confidence interval: 0.46 to 0.89; p = 0.006). Compared with the peritonitis-free group, the group experiencing peritonitis also had more drop-out from PD (p = 0.03). ♦ Conclusions: The peritonitis rate was relatively low in the present investigation. Elderly patients were at higher risk of peritonitis episodes. Peritonitis independently predicted technique failure, in agreement with other reports. However, contrary to previous studies, all-cause mortality was better in patients experiencing peritonitis than in those free of peritonitis. The underlying mechanisms of this presumptive “peritonitis paradox” remain to be clarified. PMID:24084840

  2. Understanding health decisions using critical realism: home-dialysis decision-making during chronic kidney disease.

    Science.gov (United States)

    Harwood, Lori; Clark, Alexander M

    2012-03-01

    Understanding health decisions using critical realism: home-dialysis decision-making during chronic kidney disease This paper examines home-dialysis decision making in people with Chronic Kidney Disease (CKD) from the perspective of critical realism. CKD programmes focus on patient education for self-management to delay the progression of kidney disease and the preparation and support for renal replacement therapy e.g.) dialysis and transplantation. Home-dialysis has clear health, societal and economic benefits yet service usage is low despite efforts to realign resources and educate individuals. Current research on the determinants of modality selection is superficial and insufficient to capture the complexities embedded in the process of dialysis modality selection. Predictors of home-dialysis selection and the effect of chronic kidney disease educational programmes provide a limited explanation of this experience. A re-conceptualization of the problem is required in order to fully understand this process. The epistemology and ontology of critical realism guides our knowledge and methodology particularly suited for examination of these complexities. This approach examines the deeper mechanisms and wider determinants associated with modality decision making, specifically who chooses home dialysis and under what circumstances. Until more is known regarding dialysis modality decision making service usage of home dialysis will remain low as interventions will be based on inadequate epistemology. © 2011 Blackwell Publishing Ltd.

  3. Equilibrium Trust

    OpenAIRE

    Luca Anderlini; Daniele Terlizzese

    2009-01-01

    We build a simple model of trust as an equilibrium phenomenon, departing from standard "selfish" preferences in a minimal way. Agents who are on the receiving end of an other to transact can choose whether to cheat and take away the entire surplus, taking into account a "cost of cheating." The latter has an idiosyncratic component (an agent's type), and a socially determined one. The smaller the mass of agents who cheat, the larger the cost of cheating suffered by those who cheat. Depending o...

  4. The dialysis catheter and infectious peritonitis in intermittent peritoneal dialysis

    DEFF Research Database (Denmark)

    Kolmos, Hans Jørn; Hemmeløff Andersen, Karl Erik; Hansen, Lise

    1984-01-01

    118 episodes of infectious peritonitis registered among 156 patients treated with intermittent peritoneal dialysis over a 5-yr period were analysed with special reference to potential routes of infection associated with the dialysis catheter. Peritonitis was randomly distributed among the patients......, and the change of keeping free of peritonitis declined exponentially with time. The main factor determining the individual number of episodes was the total space of time, in which a patient had been wearing a dialysis catheter, whereas the number of catheter disconnections played no significant role. A relative...... preponderance of cases due to Enterobacteriaceae was noted within the first week after catheter implantation. In contrast with this, peritonitis with skin microorganisms was not associated with the implantation of catheters....

  5. Types of vicarious learning experienced by pre-dialysis patients

    Directory of Open Access Journals (Sweden)

    Kate McCarthy

    2015-04-01

    Full Text Available Objective: Haemodialysis and peritoneal dialysis renal replacement treatment options are in clinical equipoise, although the cost of haemodialysis to the National Health Service is £16,411/patient/year greater than peritoneal dialysis. Treatment decision-making takes place during the pre-dialysis year when estimated glomerular filtration rate drops to between 15 and 30 mL/min/1.73 m2. Renal disease can be familial, and the majority of patients have considerable health service experience when they approach these treatment decisions. Factors affecting patient treatment decisions are currently unknown. The objective of this article is to explore data from a wider study in specific relation to the types of vicarious learning experiences reported by pre-dialysis patients. Methods: A qualitative study utilised unstructured interviews and grounded theory analysis during the participant’s pre-dialysis year. The interview cohort comprised 20 pre-dialysis participants between 24 and 80 years of age. Grounded theory design entailed thematic sampling and analysis, scrutinised by secondary coding and checked with participants. Participants were recruited from routine renal clinics at two local hospitals when their estimated glomerular filtration rate was between 15 and 30 mL/min/1.73 m2. Results: Vicarious learning that contributed to treatment decision-making fell into three main categories: planned vicarious leaning, unplanned vicarious learning and historical vicarious experiences. Conclusion: Exploration and acknowledgement of service users’ prior vicarious learning, by healthcare professionals, is important in understanding its potential influences on individuals’ treatment decision-making. This will enable healthcare professionals to challenge heuristic decisions based on limited information and to encourage analytic thought processes.

  6. Types of vicarious learning experienced by pre-dialysis patients.

    Science.gov (United States)

    McCarthy, Kate; Sturt, Jackie; Adams, Ann

    2015-01-01

    Haemodialysis and peritoneal dialysis renal replacement treatment options are in clinical equipoise, although the cost of haemodialysis to the National Health Service is £16,411/patient/year greater than peritoneal dialysis. Treatment decision-making takes place during the pre-dialysis year when estimated glomerular filtration rate drops to between 15 and 30 mL/min/1.73 m(2). Renal disease can be familial, and the majority of patients have considerable health service experience when they approach these treatment decisions. Factors affecting patient treatment decisions are currently unknown. The objective of this article is to explore data from a wider study in specific relation to the types of vicarious learning experiences reported by pre-dialysis patients. A qualitative study utilised unstructured interviews and grounded theory analysis during the participant's pre-dialysis year. The interview cohort comprised 20 pre-dialysis participants between 24 and 80 years of age. Grounded theory design entailed thematic sampling and analysis, scrutinised by secondary coding and checked with participants. Participants were recruited from routine renal clinics at two local hospitals when their estimated glomerular filtration rate was between 15 and 30 mL/min/1.73 m(2). Vicarious learning that contributed to treatment decision-making fell into three main categories: planned vicarious leaning, unplanned vicarious learning and historical vicarious experiences. Exploration and acknowledgement of service users' prior vicarious learning, by healthcare professionals, is important in understanding its potential influences on individuals' treatment decision-making. This will enable healthcare professionals to challenge heuristic decisions based on limited information and to encourage analytic thought processes.

  7. Dialysis: Reducing Infections and Changing Culture

    Centers for Disease Control (CDC) Podcasts

    This podcast is an account from an infection preventionist about the challenges and successes with engaging dialysis care teams to focus on "Zero Preventable Infections" in outpatient dialysis facilities.

  8. Treatment Methods for Kidney Failure: Peritoneal Dialysis

    Science.gov (United States)

    ... connect the bags of dialysis solution place the drain tube If you choose automated peritoneal dialysis, you also ... from the new bag of solution into the drain bag. Clamp the tube that goes to the drain bag. Open or ...

  9. Equilibrium thermodynamics

    CERN Document Server

    de Oliveira, Mário J

    2017-01-01

    This textbook provides an exposition of equilibrium thermodynamics and its applications to several areas of physics with particular attention to phase transitions and critical phenomena. The applications include several areas of condensed matter physics and include also a chapter on thermochemistry. Phase transitions and critical phenomena are treated according to the modern development of the field, based on the ideas of universality and on the Widom scaling theory. For each topic, a mean-field or Landau theory is presented to describe qualitatively the phase transitions. These theories include the van der Waals theory of the liquid-vapor transition, the Hildebrand-Heitler theory of regular mixtures, the Griffiths-Landau theory for multicritical points in multicomponent systems, the Bragg-Williams theory of order-disorder in alloys, the Weiss theory of ferromagnetism, the Néel theory of antiferromagnetism, the Devonshire theory for ferroelectrics and Landau-de Gennes theory of liquid crystals. This new edit...

  10. (HIV) seropositive Nigerian patients undergoing dialysis

    African Journals Online (AJOL)

    Most dialysis centres in Nigeria currently do not accept HIV positive patients for dialysis therapy for many reasons. The prevailing high level of stigmatization of HIV positive patients and the lack of job security for infected staff are two major reasons for the non-acceptance of HIV infected patients for dialysis by these centres.

  11. The economy-wide impact of pandemic influenza on the UK: a computable general equilibrium modelling experiment.

    Science.gov (United States)

    Smith, Richard D; Keogh-Brown, Marcus R; Barnett, Tony; Tait, Joyce

    2009-11-19

    To estimate the potential economic impact of pandemic influenza, associated behavioural responses, school closures, and vaccination on the United Kingdom. A computable general equilibrium model of the UK economy was specified for various combinations of mortality and morbidity from pandemic influenza, vaccine efficacy, school closures, and prophylactic absenteeism using published data. The 2004 UK economy (the most up to date available with suitable economic data). The economic impact of various scenarios with different pandemic severity, vaccination, school closure, and prophylactic absenteeism specified in terms of gross domestic product, output from different economic sectors, and equivalent variation. The costs related to illness alone ranged between 0.5% and 1.0% of gross domestic product ( pound8.4bn to pound16.8bn) for low fatality scenarios, 3.3% and 4.3% ( pound55.5bn to pound72.3bn) for high fatality scenarios, and larger still for an extreme pandemic. School closure increases the economic impact, particularly for mild pandemics. If widespread behavioural change takes place and there is large scale prophylactic absence from work, the economic impact would be notably increased with few health benefits. Vaccination with a pre-pandemic vaccine could save 0.13% to 2.3% of gross domestic product ( pound2.2bn to pound38.6bn); a single dose of a matched vaccine could save 0.3% to 4.3% ( pound5.0bn to pound72.3bn); and two doses of a matched vaccine could limit the overall economic impact to about 1% of gross domestic product for all disease scenarios. Balancing school closure against "business as usual" and obtaining sufficient stocks of effective vaccine are more important factors in determining the economic impact of an influenza pandemic than is the disease itself. Prophylactic absence from work in response to fear of infection can add considerably to the economic impact.

  12. Real-time Equilibrium Reconstruction and Isoflux Control of Plasma Shape and Position in the National Spherical Torus Experiment (NSTX)

    International Nuclear Information System (INIS)

    Mueller, D.; Gates, D.A.; Menard, J.E.; Ferron, J.R.; Sabbagh, S.A.

    2004-01-01

    The implementation of the rtEFIT-isoflux algorithm in the digital control system for NSTX has led to improved ability to control the plasma shape. In particular, it has been essential for good gap control for radio-frequency experiments, for control of drsep in H-mode studies, and for X-point height control and κ control in a variety of experiments

  13. Disaster preparedness of dialysis patients for Hurricanes Gustav and Ike 2008.

    Science.gov (United States)

    Kleinpeter, Myra A

    2009-01-01

    Hurricanes Katrina and Rita resulted in massive devastation of the Gulf Coast at Mississippi, Louisiana, and Texas during 2005. Because of those disasters, dialysis providers, nephrologists, and dialysis patients used disaster planning activities to work to mitigate the morbidity and mortality associated with the 2005 hurricane season for future events affecting dialysis patients. As Hurricane Gustav approached, anniversary events for Hurricane Katrina were postponed because of evacuation orders for nearly the entire Louisiana Gulf Coast. As part of the hurricane preparation, dialysis units reviewed the disaster plans of patients, and patients made preparation for evacuation. Upon evacuation, many patients returned to the dialysis units that had provided services during their exile from Hurricane Katrina; other patients went to other locations as part of their evacuation plan. Patients uniformly reported positive experiences with dialysis providers in their temporary evacuation communities, provided that those communities did not experience the effects of Hurricane Gustav. With the exception of evacuees to Baton Rouge, patients continued to receive their treatments uninterrupted. Because of extensive damage in the Baton Rouge area, resulting in widespread power losses and delayed restoration of power to hospitals and other health care facilities, some patients missed one treatment. However, as a result of compliance with disaster fluid and dietary recommendations, no adverse outcomes occurred. In most instances, patients were able to return to their home dialysis unit or a nearby unit to continue dialysis treatments within 4 - 5 days of Hurricane Gustav. Hurricane Ike struck the Texas Gulf Coast near Galveston, resulting in devastation of that area similar to the devastation seen in New Orleans after Katrina. The storm surge along the Louisiana Gulf Coast resulted in flooding that temporarily closed coastal dialysis units. Patients were prepared and experienced

  14. A Classroom Experiment Demonstrating the Generation of a Market Demand Function and the Determination of Equilibrium Price

    Science.gov (United States)

    Weidenaar, Dennis J.

    1972-01-01

    The simple game and discussion experiment encourages learning at the behavioral levels of application, analysis, and synthesis as well as the knowledge level. It has wide applicability in college principles of economics, advanced microeconomics courses, or high school economics. (Author/SE)

  15. The strange case of Mr. H. Starting dialysis at 90 years of age: clinical choices impact on ethical decisions.

    Science.gov (United States)

    Piccoli, Giorgina Barbara; Sofronie, Andreea Corina; Coindre, Jean-Philippe

    2017-11-09

    Starting dialysis at an advanced age is a clinical challenge and an ethical dilemma. The advantages of starting dialysis at "extreme" ages are questionable as high dialysis-related morbidity induces a reflection on the cost- benefit ratio of this demanding and expensive treatment in a person that has a short life expectancy. Where clinical advantages are doubtful, ethical analysis can help us reach decisions and find adapted solutions. Mr. H is a ninety-year-old patient with end-stage kidney disease that is no longer manageable with conservative care, in spite of optimal nutritional management, good blood pressure control and strict clinical and metabolic evaluations; dialysis is the next step, but its morbidity is challenging. The case is analysed according to principlism (beneficence, non-maleficence, justice and respect for autonomy). In the setting of care, dialysis is available without restriction; therefore the principle of justice only partially applied, in the absence of restraints on health-care expenditure. The final decision on whether or not to start dialysis rested with Mr. H (respect for autonomy). However, his choice depended on the balance between beneficence and non-maleficence. The advantages of dialysis in restoring metabolic equilibrium were clear, and the expected negative effects of dialysis were therefore decisive. Mr. H has a contraindication to peritoneal dialysis (severe arthritis impairing self-performance) and felt performing it with nursing help would be intrusive. Post dialysis fatigue, poor tolerance, hypotension and intrusiveness in daily life of haemodialysis patients are closely linked to the classic thrice-weekly, four-hour schedule. A personalized incremental dialysis approach, starting with one session per week, adapting the timing to the patient's daily life, can limit side effects and "dialysis shock". An individualized approach to complex decisions such as dialysis start can alter the delicate benefit/side-effect balance

  16. Albumin Dialysis for Liver Failure: A Systematic Review.

    Science.gov (United States)

    Tsipotis, Evangelos; Shuja, Asim; Jaber, Bertrand L

    2015-09-01

    Albumin dialysis is the best-studied extracorporeal nonbiologic liver support system as a bridge or destination therapy for patients with liver failure awaiting liver transplantation or recovery of liver function. We performed a systematic review to examine the efficacy and safety of 3 albumin dialysis systems (molecular adsorbent recirculating system [MARS], fractionated plasma separation, adsorption and hemodialysis [Prometheus system], and single-pass albumin dialysis) in randomized trials for supportive treatment of liver failure. PubMed, Ovid, EMBASE, Cochrane's Library, and ClinicalTrials.gov were searched. Two authors independently screened citations and extracted data on patient characteristics, quality of reports, efficacy, and safety end points. Ten trials (7 of MARS and 3 of Prometheus) were identified (620 patients). By meta-analysis, albumin dialysis achieved a net decrease in serum total bilirubin level relative to standard medical therapy of 8.0 mg/dL (95% confidence interval [CI], -10.6 to -5.4) but not in serum ammonia or bile acids. Albumin dialysis achieved an improvement in hepatic encephalopathy relative to standard medical therapy with a risk ratio of 1.55 (95% CI, 1.16-2.08) but had no effect survival with a risk ratio of 0.95 (95% CI, 0.84-1.07). Because of inconsistency in the reporting of adverse events, the safety analysis was limited but did not demonstrate major safety concerns. Use of albumin dialysis as supportive treatment for liver failure is successful at removing albumin-bound molecules, such as bilirubin and at improving hepatic encephalopathy. Additional experience is required to guide its optimal use and address safety concerns. Copyright © 2015 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  17. Probing the hydrogen equilibrium and kinetics in zeolite imidazolate frameworks via molecular dynamics and quasi-elastic neutron scattering experiments.

    Science.gov (United States)

    Pantatosaki, Evangelia; Jobic, Hervé; Kolokolov, Daniil I; Karmakar, Shilpi; Biniwale, Rajesh; Papadopoulos, George K

    2013-01-21

    The problem of simulating processes involving equilibria and dynamics of guest sorbates within zeolitic imidazolate frameworks (ZIF) by means of molecular dynamics (MD) computer experiments is of growing importance because of the promising role of ZIFs as molecular "traps" for clean energy applications. A key issue for validating such an atomistic modeling attempt is the possibility of comparing the MD results, with real experiments being able to capture analogous space and time scales to the ones pertained to the computer experiments. In the present study, this prerequisite is fulfilled through the quasi-elastic neutron scattering technique (QENS) for measuring self-diffusivity, by elaborating the incoherent scattering signal of hydrogen nuclei. QENS and MD experiments were performed in parallel to probe the hydrogen motion, for the first time in ZIF members. The predicted and measured dynamics behaviors show considerable concentration variation of the hydrogen self-diffusion coefficient in the two topologically different ZIF pore networks of this study, the ZIF-3 and ZIF-8. Modeling options such as the flexibility of the entire matrix versus a rigid framework version, the mobility of the imidazolate ligand, and the inclusion of quantum mechanical effects in the potential functions were examined in detail for the sorption thermodynamics and kinetics of hydrogen and also of deuterium, by employing MD combined with Widom averaging towards studying phase equilibria. The latter methodology ensures a rigorous and efficient way for post-processing the dynamics trajectory, thereby avoiding stochastic moves via Monte Carlo simulation, over the large number of configurational degrees of freedom a nonrigid framework encompasses.

  18. Conflict when making decisions about dialysis modality.

    Science.gov (United States)

    Chen, Nien-Hsin; Lin, Yu-Ping; Liang, Shu-Yuan; Tung, Heng-Hsin; Tsay, Shiow-Luan; Wang, Tsae-Jyy

    2018-01-01

    To explore decisional conflict and its influencing factors on choosing dialysis modality in patients with end-stage renal diseases. The influencing factors investigated include demographics, predialysis education, dialysis knowledge, decision self-efficacy and social support. Making dialysis modality decisions can be challenging for patients with end-stage renal diseases; there are pros and cons to both haemodialysis and peritoneal dialysis. Patients are often uncertain as to which one will be the best alternative for them. This decisional conflict increases the likelihood of making a decision that is not based on the patient's values or preferences and may result in undesirable postdecisional consequences. Addressing factors predisposing patients to decisional conflict helps to facilitate informed decision-making and then to improve healthcare quality. A predictive correlational cross-sectional study design was used. Seventy patients were recruited from the outpatient dialysis clinics of two general hospitals in Taiwan. Data were collected with study questionnaires, including questions on demographics, dialysis modality and predialysis education, the Dialysis Knowledge Scale, the Decision Self-Efficacy scale, the Social Support Scale, and the Decisional Conflict Scale. The mean score on the Decisional Conflict Scale was 29.26 (SD = 22.18). Decision self-efficacy, dialysis modality, predialysis education, professional support and dialysis knowledge together explained 76.4% of the variance in decisional conflict. Individuals who had lower decision self-efficacy, did not receive predialysis education on both haemodialysis and peritoneal dialysis, had lower dialysis knowledge and perceived lower professional support reported higher decisional conflict on choosing dialysis modality. When providing decisional support to predialysis stage patients, practitioners need to increase patients' decision self-efficacy, provide both haemodialysis and peritoneal dialysis

  19. Thermal and Mechanical Non-Equilibrium Effects on Turbulent Flows: Fundamental Studies of Energy Exchanges Through Direct Numerical Simulations, Molecular Simulations and Experiments

    Science.gov (United States)

    2016-02-26

    photochemical TNE generation, and chemistry of non- equilibrium phenomena. We have investigated a new concept to generate turbulence using photo-initiated...AFRL-AFOSR-VA-TR-2016-0104 Thermal and mechanical non- equilibrium effects on turbulent flows:fundamental studies of energy exchanges through direct...Performance 3. DATES COVERED (From - To) 15-09-2012 to 14-11-2015 4. TITLE AND SUBTITLE Thermal and mechanical non- equilibrium effects on turbulent

  20. Children of home dialysis patients.

    Science.gov (United States)

    Tsaltas, M O

    1976-12-13

    Fifteen children of six families in which one parent was undergoing home dialysis were examined by the Minnesota Multiphasic Personality Inventory, human figure drawings, and family interviews. All the children were found to be clinically depressed, and two thirds had a history of being referred by teachers to school counselors and psychiatrists for behavioral problems in school. Of these referred children, all showed disorders of psychomotor activity and reduced academic achievement. There was no clear-cut evidence that these children were depressed because of exposure to home dialysis per se. The most disturbed children seemed to be responding to depressed parents or to partial object loss. A controlled, prospective study is planned to clarify this question.

  1. Nutrition and the dialysis prescription.

    Science.gov (United States)

    Chertow, G M; Bullard, A; Lazarus, J M

    1996-01-01

    Malnutrition is common among patients with acute and chronic renal failure. The efficiency of modern dialytic techniques has allowed for more liberal administration of nutrients to patients with renal failure, particularly with regard to protein and amino acids. Protein restriction is not indicated for patients on dialysis, and should be employed cautiously, if at all, in patients with renal insufficiency. The 'nutrition prescription' should be considered a vital part of the comprehensive medical, surgical, and dialytic care provided to patients with renal disease.

  2. Anxiety disorders in dialysis patients

    OpenAIRE

    Novaković Milan

    2007-01-01

    Introduction. Anxiety, as a primary symptom, includes all conditions of indefinite fear and psychic disorders dominated by fear. All dialysis patients suffer from anxiety as an independent phenomenon, or as part of another disease. Material and Methods. This study included 753 patients on chronic hemodialysis in Bosnia and Herzegovina (B&H) in the period 1999-2004. The patients were divided into two groups: the first group included 348 patients with Balkan Endemic Nephropathy (BEN), and t...

  3. Opting out of dialysis – Exploring patients' decisions to forego dialysis in favour of conservative non-dialytic management for end-stage renal disease.

    Science.gov (United States)

    Seah, Angeline S T; Tan, Fiona; Srinivas, Subramaniam; Wu, Huei Yei; Griva, Konstadina

    2015-10-01

    Dialysis prolongs the life of people with end-stage renal disease (ESRD), but for patients who are elderly and suffer multiple comorbid illnesses the benefits of dialysis may be outweighed by its negative consequences. Non-dialytic conservative management has therefore become an alternative treatment route, yet little is known on patients' experience with choosing end-of-life treatment. To gain insight into the decision-making process leading to opting out of dialysis and the experience with conservative non-dialytic management from the patients' perspective. Qualitative study using semi-structured interviews. Interpretative phenomenological analysis was undertaken as the framework for data analysis. N = 9 ESRD participants who have taken the decision to forego dialysis were recruited from the advanced care programme under the National Healthcare Group, Singapore. Participants discussed life since ESRD diagnosis, and the personal and contextual factors that led them to choose conservative management. The perceived physical and financial burden of dialysis both for the individual but most importantly for their family, uncertainty over likely gains over risks which were fuelled by communication of negative dialysis stories of others, coupled with sense of life completion and achievement led them to refuse dialysis. All participants took ownership of their decision despite contrary advice by doctors and were content with their decision and current management. Study highlights the factors driving patients' decisions for conservative non-dialytic management over dialysis to allow medical professionals to offer appropriate support to patients through their decision-making process and in caring them for the rest of their lives. © 2013 John Wiley & Sons Ltd.

  4. Prophylactic dialysis in non-dialysis-dependent patients with renal failure after CABG

    Directory of Open Access Journals (Sweden)

    Roghayyeh Borji

    2014-03-01

    Conclusion: According the results of this study, prophylactic dialysis, before conduct-ing CABG, does not have any significant effect on mortality and other complications. The only exception is lung complications in non-dialysis-dependent patients with renal failure.

  5. [Patients' opinions and expectations about the dialysis care process].

    Science.gov (United States)

    Prieto, M A; Escudero, M J; Suess, A; March, J C; Ruiz, A; Danet, A

    2011-01-01

    To determine the experiences and needs of patients on dialysis, in order to identify critical points of the care process and develop proposals for improvement. Qualitative study using semistructured interviews with 22 patients on hemodialysis and peritoneal dialysis, from the Andalusian Health Service. Discourse analysis, using the SERVQUAL model. Triangulation of results. The diagnostic stage is described as the hardest moment as it requires acceptance of the disease. During hemodialysis, we see both positive adaptation and the perception of a diminished quality of life. The technique of peritoneal dialysis is evaluated positively, enabling greater independence, despite requiring more responsibility for self care. The contact with patients' organizations or the provision of a counseling service are valued as an aid in the process. With respect to different dimensions of the SERVQUAL model, human treatment and professional competence are valued. The critical points are lack of coordination, malfunctioning of transportation and lack of transparency in the management of waiting lists. Shortcomings in dealing with informal caregivers and the level of knowledge of professionals from areas other than Nephrology, also appear as deficiencies. The main proposals for improving the dialysis process are: attention to psychosocial aspects, the improvement of organizational aspects such as transport, and greater attention to informal caregivers.

  6. Testosterone deficiency in dialysis patients: Differences according to the dialysis techniques

    Directory of Open Access Journals (Sweden)

    Secundino Cigarrán

    2017-09-01

    Conclusions: Circulating testosterone levels in men on dialysis were independently associated with HD technique. It can be concluded that a new factor—namely the dialysis technique—may be associated with falling testosterone levels and the associated loss of muscle mass and inflammation. Further studies are needed to establish whether the dialysis technique itself triggers testosterone elimination.

  7. Burnout Syndrome Among Hemodialysis and Peritoneal Dialysis Nurses.

    Science.gov (United States)

    Karakoc, Ayten; Yilmaz, Murvet; Alcalar, Nilufer; Esen, Bennur; Kayabasi, Hasan; Sit, Dede

    2016-11-01

    Burnout, a syndrome with 3 dimensions of emotional exhaustion, depersonalization, and reduction of personal accomplishment, is very common among hemodialysis nurses, while data are scarce regarding the prevalence of burnout syndrome (BS) among peritoneal dialysis (PD) nurses. This study aimed to assess and compare demographic and professional characteristics and burnout levels in hemodialysis and PD nurses, and to investigate factors that increase the level of burnout in dialysis nurses. A total of 171 nurses from 44 dialysis centers in Turkey were included in a cross-sectional survey study. Data were collected using a questionnaire defining the social and demographic characteristics and working conditions of the nurses as well as the Maslach Burnout Inventory for assessment of burnout level. There was no significant difference in the level of burnout between the hemodialysis and PD nurses groups. Emotional exhaustion and depersonalization scores were higher among the shift workers, nurses who had problems in interactions with the other team members, and those who wanted to leave the unit, as well as the nurses who would not attend training programs. In addition, male sex, younger age, limited working experience, more than 50 hours of working per week, and working in dialysis not by choice were associated with higher depersonalization scores. Personal accomplishment score was lower among the younger nurses who had problems in their interactions with the doctors, who would not regularly attend training programs, and who felt being medically inadequate. Improving working conditions and relations among colleagues, and also providing further dialysis education are necessary for minimizing burnout syndrome. Burnout reduction programs should mainly focus on younger professionals.

  8. Correction of the equilibrium temperature caused by slight evaporation of water in protein crystal growth cells during long-term space experiments at International Space Station.

    Science.gov (United States)

    Fujiwara, Takahisa; Suzuki, Yoshihisa; Yoshizaki, Izumi; Tsukamoto, Katsuo; Murayama, Kenta; Fukuyama, Seijiro; Hosokawa, Kouhei; Oshi, Kentaro; Ito, Daisuke; Yamazaki, Tomoya; Tachibana, Masaru; Miura, Hitoshi

    2015-08-01

    The normal growth rates of the {110} faces of tetragonal hen egg-white lysozyme crystals, R, were measured as a function of the supersaturation σ parameter using a reflection type interferometer under μG at the International Space Station (NanoStep Project). Since water slightly evaporated from in situ observation cells during a long-term space station experiment for several months, equilibrium temperature T(e) changed, and the actual σ, however, significantly increased mainly due to the increase in salt concentration C(s). To correct σ, the actual C(s) and protein concentration C(p), which correctly represent the measured T(e) value in space, were first calculated. Second, a new solubility curve with the corrected C(s) was plotted. Finally, the revised σ was obtained from the new solubility curve. This correction method successfully revealed that the 2.8% water was evaporated from the solution, leading to 2.8% increase in the C(s) and C(p) of the solution.

  9. Retrieval of Kinetic Temperature and Carbon Dioxide Abundance from Non-Local Thermodynamic Equilibrium Limb Emission Measurements made by the SABER Experiment on the TIMED Satellite

    Science.gov (United States)

    Mertens, Christopher J.; Mlynczak, Martin G.; Lopez-Puertas, Manuel; Wintersteiner, Peter P.; Picard, Richard H.; Winick, Jeremy R.; Gordley, Larry L.; Russell, James M., III

    2002-01-01

    The Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) experiment was launched onboard the TIMED satellite in December, 2001. SABER is designed to provide measurements of the key radiative and chemical sources and sinks of energy in the mesosphere and lower thermosphere (MLT). SABER measures Earth limb emission in 10 broadband radiometer channels ranging from 1.27 micrometers to 17 micrometers. Measurements are made both day and night over the latitude range from 54 deg. S to 87 deg. N with alternating hemisphere coverage every 60 days. In this paper we concentrate on retrieved profiles of kinetic temperature (T(sub k)) and CO2 volume mixing ratio (vmr), inferred from SABER-observed 15 micrometer and 4.3 micrometer limb emissions, respectively. SABER-measured limb radiances are in non-local thermodynamic equilibrium (non-LTE) in the MLT region. The complexity of non-LTE radiation transfer combined with the large volume of data measured by SABER requires new retrieval approaches and radiative transfer techniques to accurately and efficiently retrieve the data products. In this paper we present the salient features of the coupled non-LTE T(sub k)/CO2 retrieval algorithm, along with preliminary results.

  10. Experiment and theory at the convergence limit: accurate equilibrium structure of picolinic acid by gas-phase electron diffraction and coupled-cluster computations.

    Science.gov (United States)

    Vogt, Natalja; Marochkin, Ilya I; Rykov, Anatolii N

    2018-04-18

    The accurate molecular structure of picolinic acid has been determined from experimental data and computed at the coupled cluster level of theory. Only one conformer with the O[double bond, length as m-dash]C-C-N and H-O-C[double bond, length as m-dash]O fragments in antiperiplanar (ap) positions, ap-ap, has been detected under conditions of the gas-phase electron diffraction (GED) experiment (Tnozzle = 375(3) K). The semiexperimental equilibrium structure, rsee, of this conformer has been derived from the GED data taking into account the anharmonic vibrational effects estimated from the ab initio force field. The equilibrium structures of the two lowest-energy conformers, ap-ap and ap-sp (with the synperiplanar H-O-C[double bond, length as m-dash]O fragment), have been fully optimized at the CCSD(T)_ae level of theory in conjunction with the triple-ζ basis set (cc-pwCVTZ). The quality of the optimized structures has been improved due to extrapolation to the quadruple-ζ basis set. The high accuracy of both GED determination and CCSD(T) computations has been disclosed by a correct comparison of structures having the same physical meaning. The ap-ap conformer has been found to be stabilized by the relatively strong NH-O hydrogen bond of 1.973(27) Å (GED) and predicted to be lower in energy by 16 kJ mol-1 with respect to the ap-sp conformer without a hydrogen bond. The influence of this bond on the structure of picolinic acid has been analyzed within the Natural Bond Orbital model. The possibility of the decarboxylation of picolinic acid has been considered in the GED analysis, but no significant amounts of pyridine and carbon dioxide could be detected. To reveal the structural changes reflecting the mesomeric and inductive effects due to the carboxylic substituent, the accurate structure of pyridine has been also computed at the CCSD(T)_ae level with basis sets from triple- to 5-ζ quality. The comprehensive structure computations for pyridine as well as for

  11. Dialysis: Reducing Infections and Changing Culture

    Centers for Disease Control (CDC) Podcasts

    2018-03-19

    This podcast is an account from an infection preventionist about the challenges and successes with engaging dialysis care teams to focus on “Zero Preventable Infections” in outpatient dialysis facilities.  Created: 3/19/2018 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 3/19/2018.

  12. Optimal Hemodialysis Prescription: Do Children Need More Than a Urea Dialysis Dose?

    Directory of Open Access Journals (Sweden)

    Fischbach Michel

    2011-01-01

    Full Text Available When prescribing hemodialysis in children, the clinician should first establish an adequate regimen, before seeking to optimize the treatment (Fischbach et al. 2005. A complete dialysis dose should consist of a urea dialysis dose and a determined convective volume. Intensified and more frequent dialysis regimens should not be considered exclusively as rescue therapy. Interestingly, a recent single-center study demonstrated that frequent on-line HDF provides an optimal dialysis prescription, both in terms of blood pressure control (and therefore avoidance of left ventricular hypertrophy, and catch-up growth, that is, no malnutrition or cachexia and less resistance to growth hormone. Nevertheless, this one-center experience would benefit from a prospective randomized study.

  13. Update on dialysis economics in the UK.

    Science.gov (United States)

    Sharif, Adnan; Baboolal, Keshwar

    2011-03-01

    The burgeoning population of patients requiring renal replacement therapy contributes a disproportionate strain on National Health Service resources. Although renal transplantation is the preferred treatment modality for patients with established renal failure, achieving both clinical and financial advantages, limitations to organ donation and clinical comorbidities will leave a significant proportion of patients with established renal failure requiring expensive dialysis therapy in the form of either hemodialysis or peritoneal dialysis. An understanding of dialysis economics is essential for both healthcare providers and clinical leaders to establish clinically efficient and cost-effective treatment modalities that maximize service provision. In light of changes to the provision of healthcare funds in the form of "Payment by Results," it is imperative for UK renal units to adopt clinically effective and financially accountable dialysis programs. This article explores the role of dialysis economics and implications for UK renal replacement therapy programs.

  14. Risky business for dialysis services.

    Science.gov (United States)

    Schohl, Joseph

    2010-05-01

    When self-insured health plans and their third-party administrators pay an artificially low out-of-network rate for dialysis services, they could be liable for the difference between that rate and the reimbursement level provided for by their health plan. Paying a rate that the repricers advised them to pay does not relieve self-insured health plans and third-party administrators of that obligation; only where the repricer has legitimately secured a negotiated contract rate is a lower payment justified. [Editor's note: The term "repricer" has no universally-accepted or formal definition, but it will be used here to describe those companies formed to act as middlemen between health care payers-like self-insured employer plans and TPAs working on behalf of such plans-and health care providers.] Failing to adhere to this will result in lawsuits against self-insured health plans and third-party administrators where they will be forced to defend the repricers' recommended payment amounts, while the repricers try to get themselves dismissed. A better option for plan holders and third-party administrators would be to negotiate directly with the dialysis providers and agree upon a mutually acceptable rate.

  15. Equilibrium Droplets on Deformable Substrates: Equilibrium Conditions.

    Science.gov (United States)

    Koursari, Nektaria; Ahmed, Gulraiz; Starov, Victor M

    2018-05-15

    Equilibrium conditions of droplets on deformable substrates are investigated, and it is proven using Jacobi's sufficient condition that the obtained solutions really provide equilibrium profiles of both the droplet and the deformed support. At the equilibrium, the excess free energy of the system should have a minimum value, which means that both necessary and sufficient conditions of the minimum should be fulfilled. Only in this case, the obtained profiles provide the minimum of the excess free energy. The necessary condition of the equilibrium means that the first variation of the excess free energy should vanish, and the second variation should be positive. Unfortunately, the mentioned two conditions are not the proof that the obtained profiles correspond to the minimum of the excess free energy and they could not be. It is necessary to check whether the sufficient condition of the equilibrium (Jacobi's condition) is satisfied. To the best of our knowledge Jacobi's condition has never been verified for any already published equilibrium profiles of both the droplet and the deformable substrate. A simple model of the equilibrium droplet on the deformable substrate is considered, and it is shown that the deduced profiles of the equilibrium droplet and deformable substrate satisfy the Jacobi's condition, that is, really provide the minimum to the excess free energy of the system. To simplify calculations, a simplified linear disjoining/conjoining pressure isotherm is adopted for the calculations. It is shown that both necessary and sufficient conditions for equilibrium are satisfied. For the first time, validity of the Jacobi's condition is verified. The latter proves that the developed model really provides (i) the minimum of the excess free energy of the system droplet/deformable substrate and (ii) equilibrium profiles of both the droplet and the deformable substrate.

  16. Adequacy in dialysis: intermittent versus continuous therapies.

    Science.gov (United States)

    Misra, M; Nolph, K D

    2000-01-01

    A vital conceptual difference between intermittent and continuous dialysis therapies is the difference in the relationship between Kt/V urea and dietary protein intake. For a given level of protein intake the intermittent therapies require a higher Kt/V urea due to the reasons mentioned above. The recently released adequacy guidelines by DOQI for intermittent and continuous therapies are based on these assumptions. The link between adequacy targets and patient survival is well documented for an intermittent therapy like HD. For a continuous therapy like CAPD however, the evidence linking improved peritoneal clearance to better survival is not as direct. However, present consensus allows one to extrapolate results based on HD. The concept of earlier and healthier initiation of dialysis is gaining hold and incremental dialysis forms an integral aspect of the whole concept. Tools like urea kinetic modeling give us valuable insight in making mathematical projections about the timing as well as dosing of dialysis. Daily home hemodialysis is still an underutilized modality despite offering best survival figures. Hopefully, with increasing availability of better and simpler machines its use will increase. Still several questions remain unanswered. Despite availability of data in hemodialysis patients suggesting that an increased dialysis prescription leads to a better survival, optimal dialysis dose is yet to be defined. Concerns regarding methodology of such studies and conclusions thereof has been raised. Other issues relating to design of the studies, variation in dialysis delivery, use of uncontrolled historical standards and lack of patient randomization etc also need to be considered when designing such trials. Hopefully an ongoing prospective randomized trial, namely the HEMO study, looking at two precisely defined and carefully maintained dialysis prescriptions will provide some insight into adequacy of dialysis dose and survival. In diabetic patients, the

  17. Sonographic evaluation of complications in patients with peritoneal dialysis

    International Nuclear Information System (INIS)

    Yoo, Won Don; Jho, O. K.; Kim, J. S.; Ko, B. H.; Park, H. C.

    1990-01-01

    Ultrasonography was performed prospectively in 20 patients who were undergoing continuous ambullatory peritoneal dialysis for evaluation of complications. We examined the abdominal wall along the course of catheter and the peritoneal cavity with special attention to the dialysate distribution, dialysate echogenecity, thickness of the peritoneum small bowel distribution and the position of the catheter tip. Peritonitis was the most common complication (n=7); sonographic findings were small bowel adhesion (n=5) multiseptated ascites(n=1), peritoneal thickening(n=4), and tunnel infection(n=1) and exith site infection(n=1). Our initial experience suggests that ultrasonography is useful for diagnosis of complications and monitoring of patient during long term peritoneal dialysis

  18. Ion exchange equilibrium constants

    CERN Document Server

    Marcus, Y

    2013-01-01

    Ion Exchange Equilibrium Constants focuses on the test-compilation of equilibrium constants for ion exchange reactions. The book first underscores the scope of the compilation, equilibrium constants, symbols used, and arrangement of the table. The manuscript then presents the table of equilibrium constants, including polystyrene sulfonate cation exchanger, polyacrylate cation exchanger, polymethacrylate cation exchanger, polysterene phosphate cation exchanger, and zirconium phosphate cation exchanger. The text highlights zirconium oxide anion exchanger, zeolite type 13Y cation exchanger, and

  19. An Assessment of Dialysis Provider's Attitudes towards Timing of Dialysis Initiation in Canada

    Directory of Open Access Journals (Sweden)

    Bikaramjit S Mann

    2014-04-01

    Full Text Available Background: Physicians' perceptions and opinions may influence when to initiate dialysis. Objective: To examine providers' perspectives and opinions regarding the timing of dialysis initiation. Design: Online survey. Setting: Community and academic dialysis practices in Canada. Participants: A nationally-representative sample of dialysis providers. Measurements and Methods: Dialysis providers opinions assessing reasons to initiate dialysis at low or high eGFR. Responses were obtained using a 9-point Likert scale. Early dialysis was defined as initiation of dialysis in an individual with an eGFR greater than or equal to 10.5 ml/min/m 2 . A detailed survey was emailed to all members of the Canadian Society of Nephrology (CSN in February 2013. The survey was designed and pre-tested to evaluate duration and ease of administration. Results: One hundred and forty one (25% response rate physicians participated in the survey. The majority were from urban, academic centres and practiced in regionally administered renal programs. Very few respondents had a formal policy regarding the timing of dialysis initiation or formally reviewed new dialysis starts (N = 4, 3.1%. The majority of respondents were either neutral or disagreed that late compared to early dialysis initiation improved outcomes (85–88%, had a negative impact on quality of life (89%, worsened AVF or PD use (84–90%, led to sicker patients (83% or was cost effective (61%. Fifty-seven percent of respondents felt uremic symptoms occurred earlier in patients with advancing age or co-morbid illness. Half (51.8% of the respondents felt there was an absolute eGFR at which they would initiate dialysis in an asymptomatic patient. The majority of respondents would initiate dialysis for classic indications for dialysis, such as volume overload (90.1% and cachexia (83.7% however a significant number chose other factors that may lead them to early dialysis initiation including avoiding an emergency (28

  20. Quantity Constrained General Equilibrium

    NARCIS (Netherlands)

    Babenko, R.; Talman, A.J.J.

    2006-01-01

    In a standard general equilibrium model it is assumed that there are no price restrictions and that prices adjust infinitely fast to their equilibrium values.In case of price restrictions a general equilibrium may not exist and rationing on net demands or supplies is needed to clear the markets.In

  1. Developing and pilot testing a shared decision-making intervention for dialysis choice.

    Science.gov (United States)

    Finderup, Jeanette; Jensen, Jens K D; Lomborg, Kirsten

    2018-04-17

    Evidence is inconclusive on how best to guide the patient in decision-making around haemodialysis and peritoneal dialysis choice. International guidelines recommend involvement of the patient in the decision to choose the dialysis modality most suitable for the individual patient. Nevertheless, studies have shown lack of involvement of the patient in decision-making. To develop and pilot test an intervention for shared decision-making targeting the choice of dialysis modality. This study reflects the first two phases of a complex intervention design: phase 1, the development process and phase 2, feasibility and piloting. Because decision aids were a part of the intervention, the International Patient Decision Aid Standards were considered. The pilot test included both the intervention and the feasibility of the validated shared decision-making questionnaire (SDM Q9) and the Decision Quality Measure (DQM) applied to evaluate the intervention. A total of 137 patients tested the intervention. After the intervention, 80% of the patients chose dialysis at home reflecting an increase of 23% in starting dialysis at home prior to the study. The SDM Q9 showed the majority of the patients experienced this intervention as shared decision-making. An intervention based on shared decision-making supported by decision aids seemed to increase the number of patients choosing home dialysis. The SDM Q9 and DQM were feasible evaluation tools. Further research is needed to gain insight into the patients' experiences of involvement and the implications for their choice of dialysis modality. © 2018 European Dialysis and Transplant Nurses Association/European Renal Care Association.

  2. Dialysis services for tourists to the Veneto Region: a qualitative study.

    Science.gov (United States)

    Footman, Katharine; Mitrio, Silva; Zanon, Dario; Glonti, Ketevan; Risso-Gill, Isabelle; McKee, Martin; Knai, Cécile

    2015-03-01

    The European Union has an established mechanism which enables patients with end-stage kidney disease (ESKD) to receive dialysis abroad, allowing them to benefit from the legal right to freedom of movement. The number of patients seeking dialysis abroad has increased in recent years and the Veneto Region of Italy, a major tourist destination, has made significant investment in providing tourist haemodialysis services. To understand the issues involved in providing dialysis services for tourists moving within the European Union, such as the experience of patients using the service, the challenges faced by professionals and patients and continuity of care. Semi-structured interviews. Interviews were conducted with patients, health professionals and key stakeholders in two dialysis centres set up for tourists in the Veneto Region's Local Health Authority 10. The study uncovered high levels of patient satisfaction and a positive impact on patients' quality of life. However, the service faces a number of challenges relating to accessibility, language barriers and continuity of care for the patient when leaving Veneto. The study also demonstrates the importance of coordinating care prior to the tourists' stay. Tourist dialysis centres are necessary to make the right to freedom of movement for patients with ESKD a reality. The findings suggest that communicating and coordinating high-quality care across borders in the EU may be facilitated by increased standardisation of norms and documents for continuity of care, such as care plans and discharge summaries. © 2014 European Dialysis and Transplant Nurses Association/European Renal Care Association.

  3. Evidence for a Shared Mechanism in the Formation of Urea-Induced Kinetic and Equilibrium Intermediates of Horse Apomyoglobin from Ultrarapid Mixing Experiments

    Science.gov (United States)

    Mizukami, Takuya; Abe, Yukiko; Maki, Kosuke

    2015-01-01

    In this study, the equivalence of the kinetic mechanisms of the formation of urea-induced kinetic folding intermediates and non-native equilibrium states was investigated in apomyoglobin. Despite having similar structural properties, equilibrium and kinetic intermediates accumulate under different conditions and via different mechanisms, and it remains unknown whether their formation involves shared or distinct kinetic mechanisms. To investigate the potential mechanisms of formation, the refolding and unfolding kinetics of horse apomyoglobin were measured by continuous- and stopped-flow fluorescence over a time range from approximately 100 μs to 10 s, along with equilibrium unfolding transitions, as a function of urea concentration at pH 6.0 and 8°C. The formation of a kinetic intermediate was observed over a wider range of urea concentrations (0–2.2 M) than the formation of the native state (0–1.6 M). Additionally, the kinetic intermediate remained populated as the predominant equilibrium state under conditions where the native and unfolded states were unstable (at ~0.7–2 M urea). A continuous shift from the kinetic to the equilibrium intermediate was observed as urea concentrations increased from 0 M to ~2 M, which indicates that these states share a common kinetic folding mechanism. This finding supports the conclusion that these intermediates are equivalent. Our results in turn suggest that the regions of the protein that resist denaturant perturbations form during the earlier stages of folding, which further supports the structural equivalence of transient and equilibrium intermediates. An additional folding intermediate accumulated within ~140 μs of refolding and an unfolding intermediate accumulated in <1 ms of unfolding. Finally, by using quantitative modeling, we showed that a five-state sequential scheme appropriately describes the folding mechanism of horse apomyoglobin. PMID:26244984

  4. Contrasting estimates on the depth of magma storage zones in volcanic systems from mineral barometry and phase equilibrium experiments: a case study from Mount Merapi, Indonesia

    Science.gov (United States)

    Erdmann, Saskia; Martel, Caroline

    2015-04-01

    Mount Merapi, located in central Java, erupts on average every 5-10 years by discharging block-and-ash flows that pose local, but spatially restricted hazards. In 2010, however, the volcano erupted with a force that has been unprecedented in over 100 years. Its proximity to the metropolis of Yogyakarta with a population of >4 million makes short- and long-term eruption forecasting a task of vital importance. Critical to the appraisal of the volcano's hazard potential are tight constraints on its upper-crustal magma plumbing system and particularly on the location of its pre-eruptive reservoir. Previous petrological studies have estimated on the basis of amphibole and clinopyroxene barometry that the main magma storage zone below Merapi is located at depths of >10-15 km, while geophysical surveys have inferred significant magma storage zones at depths of ~5.5-9 km. We have carried out phase equilibrium experiments on basaltic andesite erupted in 2010, which indicate that the main pre-eruptive reservoir is located at a depth of ~7-8 km (~200 MPa). Our results thus corroborate the findings of earlier geophysical surveys and highlight the extreme uncertainty of mineral-based pressure estimates for volcanic magma systems. We point out that the commonly employed amphibole barometric calibrations of Ridolfi et al. (2010) and Ridolfi & Renzulli (2012) calculate low crystallization pressure for amphibole crystallized from felsic melt and high crystallization pressure for amphibole crystallized from mafic melt, and that the calculated pressure is thus largely unrelated to true values. Commonly employed clinopyroxene barometers (e.g., those of Nimis 1999; Putirka 2008) are also of limited use for estimating the location of crustal magma reservoirs, because the methods have large standard errors and are extremely temperature-sensitive. As a result, the calculated crystallization pressures inevitably indicate crystallization over a large range of depths, often from deep- to

  5. Electronic states and nature of bonding in the molecule YC by all electron ab initio multiconfiguration self-consistent-field calculations and mass spectrometric equilibrium experiments

    DEFF Research Database (Denmark)

    Shim, Irene; Pelino, Mario; Gingerich, Karl A.

    1992-01-01

    , and they hardly contribute to the bonding. The chemical bond in the YC molecule is polar with charge transfer from Y to C giving rise to a dipole moment of 3.90 D at 3.9 a.u. in the 4PI ground state. Mass spectrometric equilibrium investigations in the temperature range 2365-2792 K have resulted...

  6. Unplanned Start on Peritoneal Dialysis Right after PD Catheter Implantation for Older People with End-Stage Renal Disease.

    Science.gov (United States)

    Povlsen, Johan V; Sørensen, Anette Bagger; Ivarsen, Per

    2015-11-01

    Unplanned start on dialysis remains a major problem for the dialysis community worldwide. Late-referred patients with end-stage renal disease (ESRD) and urgent need for dialysis are overrepresented among older people. These patients are particularly likely to be started on in-center hemodialysis (HD), with a temporary vascular access known to be associated with excess mortality and increased risks of potentially lethal complications such as bacteremia and central venous thrombosis or stenosis.The present paper describes in detail our program for unplanned start on automated peritoneal dialysis (APD) right after PD catheter implantation and summarizes our experiences with the program so far. Compared with planned start on PD after at least 2 weeks of break-in between PD catheter implantation and initiation of dialysis, unplanned start may be associated with a slight increased risk of mechanical complications but apparently no detrimental effect on mortality, peritonitis-free survival, or PD technique survival.In our opinion and experience, the risk of serious complications associated with the implantation and immediate use of a PD catheter is less than the risk of complications associated with unplanned start on HD with a temporary central venous catheter (CVC). Unplanned start on APD is a gentle, safe, and feasible alternative to unplanned start on HD with a temporary CVC that is also valid for the late-referred older patient with ESRD and urgent need for dialysis. Copyright © 2015 International Society for Peritoneal Dialysis.

  7. Are Diuretics Underutilized in Dialysis Patients?

    Science.gov (United States)

    Trinh, Emilie; Bargman, Joanne M

    2016-09-01

    While oral diuretics are commonly used in patients with chronic kidney disease for the management of volume and blood pressure, they are often discontinued upon initiation of dialysis. We suggest that diuretics are considerably underutilized in peritoneal dialysis and haemodialysis patients despite numerous potential benefits and few side effects. Moreover, when diuretics are used, optimal doses are not always prescribed. In peritoneal dialysis, the use of diuretics can improve volume status and minimize the need for higher glucose-containing solutions. In patients on haemodialysis, diuretics can help lessen interdialytic weight gain, resulting in decreased ultrafiltration rates and fewer episodes of intradialytic hypotension. This paper will review the mechanism of action of diuretics in patients with renal insufficiency, quantify the risk of side effects and elaborate on the potential advantages of diuretic use in peritoneal dialysis and hemodialysis patients with residual kidney function. © 2016 Wiley Periodicals, Inc.

  8. Collagen markers in peritoneal dialysis patients

    DEFF Research Database (Denmark)

    Graff, J; Joffe, P; Fugleberg, S

    1995-01-01

    Possible relationships between the dialysate-to-plasma creatinine equilibration ratio (D/Pcreatinine 4 hour), duration of peritoneal dialysis treatment, number of peritonitis episodes, and mass appearance rates of three connective tissue markers [carboxyterminal propeptide of type I procollagen...... (PICP), aminoterminal propeptide of type III procollagen (PIIINP), and carboxyterminal telopeptide of type I collagen (ICTP)] were studied in 19 nondiabetic peritoneal dialysis patients. The absence of correlation between the mass appearance rates of the markers and the duration of dialysis treatment...... as well as the number of peritonitis episodes supports the concept that peritoneal dialysis does not cause persistent changes in the deposition and degradation rates of collagen. A correlation between the D/Pcreatinine 4 hr and the PICP mass appearance rates was found. Since it is unlikely...

  9. Dialysis: MedlinePlus Health Topic

    Science.gov (United States)

    ... access for hemodialysis (Medical Encyclopedia) Also in Spanish Topic Image MedlinePlus Email Updates Get Dialysis updates by ... for hemodialysis Show More Show Less Related Health Topics Creatinine Kidney Cysts Kidney Failure Peritoneal Disorders National ...

  10. Intraperitoneal pressure in peritoneal dialysis

    Directory of Open Access Journals (Sweden)

    Vicente Pérez Díaz

    2017-11-01

    Full Text Available The measure of intraperitoneal pressure in peritoneal dialysis is easy and provides clear therapeutic benefits. However it is measured only rarely in adult peritoneal dialysis units. This review aims to disseminate the usefulness of measuring intraperitoneal pressure. This measurement is performed in supine before initiating the drain of a manual exchange with “Y” system, by raising the drain bag and measuring from the mid-axillary line the height of the liquid column that rises from the patient. With typical values of 10–16 cm H2O, intraperitoneal pressure should never exceed 18 cm H2O. With basal values that depend on body mass index, it increases 1–3 cm H2O/L of intraperitoneal volume, and varies with posture and physical activity. Its increase causes discomfort, sleep and breathing disturbances, and has been linked to the occurrence of leaks, hernias, hydrothorax, gastro-esophageal reflux and enteric peritonitis. Less known and valued is its ability to decrease the effectiveness of dialysis significantly counteracting ultrafiltration and decreasing solute clearance to a smaller degree. Because of its easy measurement and potential utility, should be monitored in case of ultrafiltration failure to rule out its eventual contribution in some patients. Although not yet mentioned in the clinical practice guidelines for PD, its clear benefits justify its inclusion among the periodic measurements to consider for prescribing and monitoring peritoneal dialysis. Resumen: La medida de la presión intraperitoneal en diálisis peritoneal es muy sencilla y aporta claros beneficios terapéuticos. Sin embargo, su monitorización todavía no se ha generalizado en las unidades de diálisis peritoneal de adultos. Esta revisión pretende divulgar su conocimiento y la utilidad de su medida. Se realiza en decúbito antes de iniciar el drenaje de un intercambio manual con bolsa en Y, elevando la bolsa de

  11. User-driven conversations about dialysis through Facebook: A qualitative thematic analysis.

    Science.gov (United States)

    Ahmed, Salim; Haines-Saah, Rebecca J; Afzal, Arfan R; Tam-Tham, Helen; Al Mamun, Mohammad; Hemmelgarn, Brenda R; Turin, Tanvir C

    2017-04-01

    As one of the most popular social networking sites in the world, Facebook has strong potential to enable peer support and the user-driven sharing of health information. We carried out a qualitative thematic analysis of the wall posts of a public Facebook group focused on dialysis to identify some of the major themes discussed. We searched Facebook using the word 'dialysis'. A Facebook group (Dialysis Discussion Uncensored) with the highest number of members was selected amongst publicly available forums related to dialysis and operated in English (http://www.facebook.com/groups/DialysisUncensored). Two researchers independently extracted information on features of the group including purpose, group members and the user-generated posts on the group wall. Posts were further analysed to develop major themes. Characteristics of a Facebook group based on its participants and activities are presented. Three themes are described with representative quotations. In a period of 2 weeks, we found 1257 wall posts with total of 31 636 likes and 15 972 comments. All messages were in English, and the majority of the participants were dialysis patients. However, we observed the participation of family members and care providers as well. Posts were categorized into three major themes: sharing information, seeking and providing emotional and social support and sharing experience. Findings of this study provide an example of how a social networking platform can enable patients and their families to share information and to encourage peer-based support for managing dialysis-related experiences. © 2016 Asian Pacific Society of Nephrology.

  12. The equilibrium response to doubling atmospheric CO2

    International Nuclear Information System (INIS)

    Mitchell, J.F.B.

    1990-01-01

    The equilibrium response of climate to increased atmospheric carbon dioxide as simulated by general circulation models is assessed. Changes that are physically plausible are summarized, along with an indication of the confidence attributable to those changes. The main areas of uncertainty are highlighted. They include: equilibrium experiments with mixed-layer oceans focusing on temperature, precipitation, and soil moisture; equilibrium studies with dynamical ocean-atmosphere models; results deduced from equilibrium CO 2 experiments; and priorities for future research to improve atmosphere models

  13. Phase equilibrium engineering

    CERN Document Server

    Brignole, Esteban Alberto

    2013-01-01

    Traditionally, the teaching of phase equilibria emphasizes the relationships between the thermodynamic variables of each phase in equilibrium rather than its engineering applications. This book changes the focus from the use of thermodynamics relationships to compute phase equilibria to the design and control of the phase conditions that a process needs. Phase Equilibrium Engineering presents a systematic study and application of phase equilibrium tools to the development of chemical processes. The thermodynamic modeling of mixtures for process development, synthesis, simulation, design and

  14. Equilibrium and generators

    International Nuclear Information System (INIS)

    Balter, H.S.

    1994-01-01

    This work studies the behaviour of radionuclides when it produce a desintegration activity,decay and the isotopes stable creation. It gives definitions about the equilibrium between activity of parent and activity of the daughter, radioactive decay,isotope stable and transient equilibrium and maxim activity time. Some considerations had been given to generators that permit a disgregation of two radioisotopes in equilibrium and its good performance. Tabs

  15. Restless legs syndrome in patients on dialysis

    International Nuclear Information System (INIS)

    AlJahdali, Hamdan H; AlQadhi, Waleed A; Khogeer, Haithm A; AlHejaili, Fayez F; Al Sayyari, Abdullah A; AlGhamdi, Saeed M

    2009-01-01

    Restless legs syndrome (RLS) is an extremely distressing problem experienced by patients on dialysis; the prevalence appears to be greater than in the general population, with a wide variation from 6.6% to 80%. The diagnosis of RLS is a clinical one, and its definition has been clarified and standardized by internationally recognized diagnostic criteria, published in 1995 by the International Restless Legs Syndrome Study Group (IRLSSG). This study was designed to find out the prevalence of RLS in Saudi patients with end-stage renal disease (ESRD) on maintenance dialysis. This is a cross sectional study carried out between May and Sept 2007 at two centers, King Abdulaziz Medical City-King Fahad National Guard Hospital (KAMC-KFNGH), Riyadh and King Faisal Specialist Hospital and Research Centre (KFHRC), Jeddah, Saudi Arabia. Data were gathered on 227 Saudi patients on chronic maintenance hemodialysis or chronic peritoneal dialysis. The prevalence of RLS was measured using IRLSSG's RLS Questionnaire (RLSQ). Potential risk factors for RLS including other sleep disorders, underlying cause of chronic renal failure, duration on dialysis, dialysis shift, biochemical tests and demographic data were also evaluated. The overall prevalence of RLS was 50.22% including 53.7% males and 46.3% females. Their mean age was 55.7 + - 17.2 years and mean duration on dialysis 40.4 + - 37.8 months. Significant predictors of RLS were history of diabetes mellitus (DM), coffee intake, afternoon dialysis, gender and type of dialysis (P= 0.03, 0.01, < 0.001, 0.05 and 0.009 respectively). Patients with RLS were found to be at increased risk of having insomnia and excessive daytime sleepiness (EDS) (P= < 0.001 and 0.001, respectively). Our study suggests that RLS is a very common problem in dialysis population and was significantly associated with other sleep disorders, particularly insomnia, and EDS. Optimal care of dialysis patient should include particular attention to the diagnosis and

  16. Restless legs syndrome in patients on dialysis

    Directory of Open Access Journals (Sweden)

    Al-Jahdali Hamdan

    2009-01-01

    Full Text Available Restless legs syndrome (RLS is an extremely distressing problem experienced by patients on dialysis; the prevalence appears to be greater than in the general population, with a wide variation from 6.6% to 80%. The diagnosis of RLS is a clinical one, and its definition has been clarified and standardized by internationally recognized diagnostic criteria, published in 1995 by the International Restless Legs Syndrome Study Group (IRLSSG. This study was designed to find out the prevalence of RLS in Saudi patients with end-stage renal disease (ESRD on maintenance dialysis. This is a cross sectional study carried out between May and Sept 2007 at two centers, King Abdulaziz Medical City-King Fahad National Guard Hospital (KAMC-KFNGH, Riyadh and King Faisal Specialist Hospital and Research Centre (KFHRC, Jeddah, Saudi Arabia. Data were gathered on 227 Saudi patients on chronic maintenance hemodialysis or chronic peritoneal dialysis. The prevalence of RLS was measured using IRLSSG′s RLS Questionnaire (RLSQ. Potential risk factors for RLS including other sleep disorders, underlying cause of chronic renal failure, duration on dialysis, dialysis shift, biochemical tests and demographic data were also evaluated. The overall prevalence of RLS was 50.22% including 53.7% males and 46.3% females. Their mean age was 55.7 ± 17.2 years and mean duration on dialysis 40.4 ± 37.8 months. Significant predictors of RLS were history of diabetes mellitus (DM, coffee intake, afternoon dialysis, gender and type of dialysis (P= 0.03, 0.01, < 0.001, 0.05 and 0.009 respectively. Patients with RLS were found to be at increased risk of having insomnia and excessive daytime sleepiness (EDS (P= < 0.001 and 0.001, respectively. Our study suggests that RLS is a very common problem in dialysis population and was significantly associated with other sleep disorders, particularly insomnia, and EDS. Optimal care of dialysis patient should include particular attention to the diagnosis

  17. Evaluation of biofouling in stainless microfluidic channels for implantable multilayered dialysis device

    Science.gov (United States)

    Ota, Takashi; To, Naoya; Kanno, Yoshihiko; Miki, Norihisa

    2017-06-01

    An implantable artificial kidney can markedly improve the quality of life of renal disease patients. Our group has developed an implantable multilayered dialysis system consisting of microfluidic channels and dialysis membranes. Long-term evaluation is necessary for implant devices where biofouling is a critical factor, culminating in the deterioration of dialysis performance. Our previous work revealed that surface conditions, which depend on the manufacturing process, determine the amount of biofouling, and that electrolytic etching is the most suitable technique for forming a channel wall free of biofouling. In this study, we investigated the electrolytic etching conditions in detail. We conducted in vitro experiments for 7 d and evaluated the adhesion of biomaterials by scanning electron microscopy. The experiments revealed that a surface mirror-finished by electrolytic etching effectively prevents biofouling.

  18. Biogeochemical processes in a clay formation in situ experiment: Part E - Equilibrium controls on chemistry of pore water from the Opalinus Clay, Mont Terri Underground Research Laboratory, Switzerland

    Energy Technology Data Exchange (ETDEWEB)

    Pearson, F.J., E-mail: fjpearson@gmail.com [Ground-Water Geochemistry, 5108 Trent Woods Dr., New Bern, NC 28562 (United States); Tournassat, Christophe; Gaucher, Eric C. [BRGM, B.P. 36009, 45060 Orleans Cedex 2 (France)

    2011-06-15

    Highlights: > Equilibrium models of water-rock reactions in clay rocks are reviewed. > Analyses of pore waters of the Opalinus Clay from boreholes in the Mont Terri URL, Switzerland, are tabulated. > Results of modelling with various mineral controls are compared with the analyses. > Best agreement results with calcite, dolomite and siderite or daphnite saturation, Na-K-Ca-Mg exchange and/or kaolinite, illite, quartz and celestite saturation. > This approach allows calculation of the chemistry of pore water in clays too impermeable to yield water samples. - Abstract: The chemistry of pore water (particularly pH and ionic strength) is an important property of clay rocks being considered as host rocks for long-term storage of radioactive waste. Pore waters in clay-rich rocks generally cannot be sampled directly. Instead, their chemistry must be found using laboratory-measured properties of core samples and geochemical modelling. Many such measurements have been made on samples from the Opalinus Clay from the Mont Terri Underground Research Laboratory (URL). Several boreholes in that URL yielded water samples against which pore water models have been calibrated. Following a first synthesis report published in 2003, this paper presents the evolution of the modelling approaches developed within Mont Terri URL scientific programs through the last decade (1997-2009). Models are compared to the composition of waters sampled during dedicated borehole experiments. Reanalysis of the models, parameters and database enabled the principal shortcomings of the previous modelling efforts to be overcome. The inability to model the K concentrations correctly with the measured cation exchange properties was found to be due to the use of an inappropriate selectivity coefficient for Na-K exchange; the inability to reproduce the measured carbonate chemistry and pH of the pore waters using mineral-water reactions alone was corrected by considering clay mineral equilibria. Re

  19. Performance measures for a dialysis setting.

    Science.gov (United States)

    Gu, Xiuzhu; Itoh, Kenji

    2018-03-01

    This study from Japan extracted performance measures for dialysis unit management and investigated their characteristics from professional views. Two surveys were conducted using self-administered questionnaires, in which dialysis managers/staff were asked to rate the usefulness of 44 performance indicators. A total of 255 managers and 2,097 staff responded. Eight performance measures were elicited from dialysis manager and staff responses: these were safety, operational efficiency, quality of working life, financial effectiveness, employee development, mortality, patient/employee satisfaction and patient-centred health care. These performance measures were almost compatible with those extracted in overall healthcare settings in a previous study. Internal reliability, content and construct validity of the performance measures for the dialysis setting were ensured to some extent. As a general trend, both dialysis managers and staff perceived performance measures as highly useful, especially for safety, mortality, operational efficiency and patient/employee satisfaction, but showed relatively low concerns for patient-centred health care and employee development. However, dialysis managers' usefulness perceptions were significantly higher than staff. Important guidelines for designing a holistic hospital/clinic management system were yielded. Performance measures must be balanced for outcomes and performance shaping factors (PSF); a common set of performance measures could be applied to all the healthcare settings, although performance indicators of each measure should be composed based on the application field and setting; in addition, sound causal relationships between PSF and outcome measures/indicators should be explored for further improvement. © 2017 European Dialysis and Transplant Nurses Association/European Renal Care Association.

  20. Potential Role of Vegetarianism on Nutritional and Cardiovascular Status in Taiwanese Dialysis Patients: A Case-Control Study.

    Directory of Open Access Journals (Sweden)

    Shih-Hsiang Ou

    Full Text Available Cardiovascular disease remains the most common cause of death for patients on chronic dialysis. End stage renal disease patients undergoing dialysis imposed to reduce phosphorus intake, which likely contributes to development of vegetarian diet behaviors. Vegetarian diets are often lower in protein content, in contradiction to the recommendation that a high protein diet is followed by patients undergoing dialysis. The purpose of the study was to investigate the effects of a vegetarian diet on the nutritional and cardiovascular status of dialysis patients.A study of 21 vegetarian dialysis patients and 42 age- and sex-matched non-vegetarian dialysis patients selected as controls was conducted in the Kaohsiung Veterans General Hospital. Brachial-ankle pulse wave velocity and biochemistry data including total homocysteine levels, serum lipid profiles, high-sensitivity C-reactive protein, vitamin D levels, albumin, and normalized protein catabolic rate were measured.Compared with the non-vegetarian control group, vegetarian subjects had lower body weight, body mass index, serum phosphate, blood urea nitrogen, serum creatinine, vitamin D, uric acid, albumin, and normalized protein catabolic rate (p < 0.05. The vegetarian group showed higher brachial-ankle pulse wave velocity than the non-vegetarian group (1926.95 ± 456.45 and 1684.82 ± 309.55 cm/sec, respectively, p < 0.05. After adjustment for age, albumin, pre-dialysis systolic blood pressure, and duration of dialysis, vegetarian diet remained an independent risk factor for brachial-ankle pulse wave velocity.The present study revealed that patients on dialysis who follow vegetarian diets may experience subclinical protein malnutrition and vitamin D deficiency that could offset the beneficial cardiovascular effects of vegetarianism.

  1. Phase equilibrium of (CO2 + 1-aminopropyl-3-methylimidazolium bromide + water) electrolyte system and effects of aqueous medium on CO2 solubility: Experiment and modeling

    International Nuclear Information System (INIS)

    Chen, Ying; Guo, Kaihua; Bi, Yin; Zhou, Lan

    2017-01-01

    Highlights: • Phase and chemical equilibrium data for (CO 2 + [APMIm]Br + H 2 O) electrolyte system. • A modified eNRTL model for CO 2 solubility in the amino-based IL aqueous solution. • Effects of aqueous medium on both chemical and physical dissolution of CO 2 . • The correlative coefficient, R s ∗ , for the Henry’s constant of the solution. • New parameters for the segments interaction and the chemical equilibrium constants. - Abstract: New experimental data for solubility of carbon dioxide (CO 2 ) in the aqueous solution of 1-aminopropyl-3-methylimidazolium bromide ([APMIm]Br) with four different water mass fractions (0.559, 0.645, 0.765 and 0.858) at T = (278.15–348.15) K with an interval of T = 10 K and p = (0.1237–6.9143) MPa were presented. The electrolyte nonrandom two-liquid (eNRTL) model was modified to be applicable for an ionic liquid (IL) aqueous solution system, by introducing an idle factor β to illustrate the association effect of IL molecules. A solution Henry’s constant for CO 2 solubility in the IL aqueous solution was defined by introducing a correlative coefficient R s ∗ . The vapor-liquid phase equilibrium of the [APMIm]Br-H 2 O-CO 2 ternary system was successfully calculated with the modified eNRTL model. The chemical and physical mechanisms for the ionized CO 2 formation and the molecular CO 2 dissolved in the solution were identified. The effects of aqueous medium on both chemical and physical dissolution of CO 2 in the [APMIm]Br aqueous solution were studied, and a considerable enhancement of the solubility of CO 2 with increase of the water content in the solution was observed.

  2. A data acquisition system for real-time magnetic equilibrium reconstruction on ASDEX Upgrade and its application to NTM stabilization experiments

    Energy Technology Data Exchange (ETDEWEB)

    Giannone, L., E-mail: Louis.Giannone@ipp.mpg.de [Max Planck Institute for Plasma Physics, EURATOM Association, 85748 Garching (Germany); Reich, M.; Maraschek, M.; Poli, E.; Rapson, C.; Barrera, L.; McDermott, R.; Mlynek, A. [Max Planck Institute for Plasma Physics, EURATOM Association, 85748 Garching (Germany); Ruan, Q. [National Instruments, Austin, TX 78759-3504 (United States); Treutterer, W. [Max Planck Institute for Plasma Physics, EURATOM Association, 85748 Garching (Germany); Wenzel, L. [National Instruments, Austin, TX 78759-3504 (United States); Bock, A.; Conway, G.; Fischer, R.; Fuchs, J.C.; Lackner, K. [Max Planck Institute for Plasma Physics, EURATOM Association, 85748 Garching (Germany); McCarthy, P.J. [Department of Physics, University College Cork, Association EURATOM-DCU, Cork (Ireland); Preuss, R. [Max Planck Institute for Plasma Physics, EURATOM Association, 85748 Garching (Germany); Rampp, M. [Computing Centre (RZG) of the Max Planck Society and the Max Planck Institute for Plasma Physics, 85748 Garching (Germany); Schuhbeck, K.H. [Max Planck Institute for Plasma Physics, EURATOM Association, 85748 Garching (Germany); and others

    2013-12-15

    Highlights: • Calculation of real-time tokamak magnetic equilibrium with constraints from magnetic probes. • Parallel equilibrium calculation including the Motional Stark Effect diagnostic as additional constraints. • Feedback control of mirror for pre-emptive ECCD stabilization of neo-classical tearing modes. • Probe calibration by individual poloidal field coil currents. • Optimized parameters for poloidal field coil location, integrator gains and the location and orientation of magnetic probes. -- Abstract: The pre-emptive stabilization of a neoclassical tearing mode, NTM, requires the calculation of the tokamak magnetic equilibrium in real-time. A launcher mirror is positioned to deposit electron cyclotron current drive on the rational surface where the NTM should appear. A real-time Grad–Shafranov solver using constraints from magnetic probe, flux loop and Motional Stark Effect measurements has been developed to locate these rational surfaces and deliver this information to the mirror controller in real-time. A novel algorithm significantly reduces the number of operations required in the first and second step of the solver. Contour integrals are carried out to calculate the q profile as a function of normalized radius and the rational surfaces are found by spline interpolation. A cycle time of 0.6 ms for calculating two tokamak equilibria in parallel using four current basis functions with magnetic constraints only and using six current basis functions with magnetic and MSE constraints has been achieved. Using these tools, pre-emptive stabilization of a m/n = 3/2 NTM mode in ASDEX Upgrade could be demonstrated.

  3. Administration of calcimimetics after dialysis: Same effectiveness, better gastrointestinal tolerability

    Directory of Open Access Journals (Sweden)

    Vicent Esteve Simo

    2015-07-01

    Conclusions: Post-dialysis use of calcimimetic was effective in secondary hyperparathyroidism control, improved gastrointestinal tolerability and ameliorated patients’ satisfaction. Based on our findings, post-dialysis use of calcimimetics should be considered in selected patients with low therapeutic compliance.

  4. Clostridium difficile-associated diarrhea in dialysis patients

    Directory of Open Access Journals (Sweden)

    Sook Eui Oh

    2013-03-01

    Conclusion: Our data indicate that dialysis patients might be at a greater risk of developing CDAD, which suggests that particular attention should be provided to CDAD when antibiotic treatment is administered to dialysis patients.

  5. Nutritional status of maintenance dialysis patients

    DEFF Research Database (Denmark)

    Koefoed, Mette Juul; Kromann, Charles Boy; Juliussen, Sophie Ryberg

    2016-01-01

    Background and Aims Maintenance dialysis patients are at increased risk of abnormal nutritional status due to numerous causative factors, both nutritional and non-nutritional. The present study assessed the current prevalence of protein-energy wasting, low lean bodymass index and obesity...... protein catabolic rate in order to assess the prevalence of protein-energy wasting, low lean body mass index and obesity in these patients. Results Seventy-nine eligible maintenance dialysis patients participated. The prevalence of proteinenergy wasted patients was 4%(95%CI: 2-12) as assessed......-energy wasting and obesity varied considerably, depending on nutritional assessment methodology. Conclusions Our data indicate that protein-energy wasting is uncommon, whereas low lean body mass index and obesity are frequent conditions among patients in maintenance dialysis. A focus on how to increase...

  6. Cardiovascular and noncardiovascular mortality among men and women starting dialysis

    DEFF Research Database (Denmark)

    Carrero, Juan J; de Jager, Dinanda J; Verduijn, Marion

    2011-01-01

    Although women have a survival advantage in the general population, women on dialysis have similar mortality to men. We hypothesized that this paired mortality risk during dialysis may be explained by a relative excess of cardiovascular-related mortality in women.......Although women have a survival advantage in the general population, women on dialysis have similar mortality to men. We hypothesized that this paired mortality risk during dialysis may be explained by a relative excess of cardiovascular-related mortality in women....

  7. Equilibrium and non equilibrium in fragmentation

    International Nuclear Information System (INIS)

    Dorso, C.O.; Chernomoretz, A.; Lopez, J.A.

    2001-01-01

    Full text: In this communication we present recent results regarding the interplay of equilibrium and non equilibrium in the process of fragmentation of excited finite Lennard Jones drops. Because the general features of such a potential resemble the ones of the nuclear interaction (fact that is reinforced by the similarity between the EOS of both systems) these studies are not only relevant from a fundamental point of view but also shed light on the problem of nuclear multifragmentation. We focus on the microscopic analysis of the state of the fragmenting system at fragmentation time. We show that the Caloric Curve (i e. the functional relationship between the temperature of the system and the excitation energy) is of the type rise plateau with no vapor branch. The usual rise plateau rise pattern is only recovered when equilibrium is artificially imposed. This result puts a serious question on the validity of the freeze out hypothesis. This feature is independent of the dimensionality or excitation mechanism. Moreover we explore the behavior of magnitudes which can help us determine the degree of the assumed phase transition. It is found that no clear cut criteria is presently available. (Author)

  8. Optimizing home dialysis: role of hemodiafiltration.

    Science.gov (United States)

    Vilar, Enric; Farrington, Ken; Bates, Chris; Mumford, Carol; Greenwood, Roger

    2011-01-01

    Over the last 40 years the technical obstacles which prevented a convective contribution to diffusive dialysis have been overcome. Hemodiafiltration represents a natural evolution of intermittent extracorporeal blood purification and the technology is now available to offer this as standard treatment in-center. The first randomized control trial of dialysis dose (National Cooperative Dialysis Study) showed that for three times weekly dialysis a critical level of urea clearance was necessary to ensure complication-free survival, the effect being noticeable by 3 months. Following this, observational studies suggested that higher doses improved longer term outcome. In a second large randomized controlled study (HEMO), higher small molecule clearance did not further improve outcome, but high-flux membranes, which permitted enhanced clearance of middle molecules, appeared to confer survival benefit in patients who had already been on dialysis > 3.7 years. Recently, outcomes from the Membrane Permeability Outcome study confirmed a survival benefit of high-flux membranes in high-risk patients. These studies indicate that in the medium term survival is critically dependent on achieving a minimum level of small solute removal. However, longer term survival (measured in years or decades) not only requires better small solute clearance but also enhanced clearance of middle molecules, the toxicity of which manifest over longer time scales. The rationale for convective treatment is strongest, therefore in those patients who have the greatest potential for long-term survival. Patients who opt for self-care at home to allow frequent dialysis generally are constituents of this group. Hemodiafiltration is likely to become standard therapy in-center and in the home. Copyright © 2011 S. Karger AG, Basel.

  9. Acute hydrothorax from peritoneal dialysis successfully treated with new dialysis regime

    International Nuclear Information System (INIS)

    Lim, C.T.S.; Thong, K.M.

    2015-01-01

    Hydrothorax is a rare and often unrecognized complication associated with peritoneal dialysis (PD). This is usually due to the presence of pleuroperitoneal fistula. Most nephrologist will choose to cease the peritoneal dialysis and rest the peritoneum. More than often surgical interventions include pleurodesis or thoracotomy will be required. In this report, we reported a patient who developed pleural effusion after starting continuous ambulatory peritoneal dialysis. She was successfully managed by the use of low volume exchange during daytime with avoidance of conversion to haemodialysis or any surgical intervention. (author)

  10. Chemical Principles Revisited: Chemical Equilibrium.

    Science.gov (United States)

    Mickey, Charles D.

    1980-01-01

    Describes: (1) Law of Mass Action; (2) equilibrium constant and ideal behavior; (3) general form of the equilibrium constant; (4) forward and reverse reactions; (5) factors influencing equilibrium; (6) Le Chatelier's principle; (7) effects of temperature, changing concentration, and pressure on equilibrium; and (8) catalysts and equilibrium. (JN)

  11. Australian consumer perspectives on dialysis: first national census.

    Science.gov (United States)

    Ludlow, Marie J; Lauder, Lydia A; Mathew, Timothy H; Hawley, Carmel M; Fortnum, Debbie

    2012-11-01

    The percentage of people in Australia who undertake home dialysis has steadily decreased over the past 40 years and varies within Australia. Consumer factors related to this decline have not previously been determined. A 78-question survey was developed and piloted in 2008 and 2009. Survey forms were distributed to all adult routine dialysis patients in all Australian states and territories (except Northern Territory) between 2009 and 2010. Of 9223 distributed surveys, 3250 were completed and returned. 49% of respondents indicated they had no choice in the type of dialysis and 48% had no choice in dialysis location. Respondents were twice as likely to receive information about haemodialysis (85%) than APD (39%) or CAPD (41%). The provision of education regarding home modalities differed significantly between states, and decreased with increasing patient age. Additional nursing support and reimbursement of expenses increased the proportion of those willing to commence dialysis at home, from 13% to 34%. State differences in the willingness to consider home dialysis, the degree of choice in dialysis location, the desire to change current dialysis type and/or location, and the provision of information about dialysis were identified. The delivery of pre-dialysis education is variable, and does not support all options of dialysis for all individuals. State variances indicate that local policy and health professional teams significantly influence the operation of dialysis programs. © 2012 The Authors. Nephrology © 2012 Asian Pacific Society of Nephrology.

  12. Quality of life in automated and continuous ambulatory peritoneal dialysis

    NARCIS (Netherlands)

    Michels, Wieneke M.; van Dijk, Sandra; Verduijn, Marion; le Cessie, Saskia; Boeschoten, Elisabeth W.; Dekker, Friedo W.; Krediet, Raymond T.; Apperloo, A. J.; Bijlsma, J. A.; Boekhout, M.; Boer, W. H.; van der Boog, P. J. M.; Büller, H. R.; van Buren, M.; de Charro, F. Th; Doorenbos, C. J.; van den Dorpel, M. A.; van Es, A.; Fagel, W. J.; Feith, G. W.; de Fijter, C. W. H.; Frenken, L. A. M.; Grave, W.; van Geelen, J. A. C. A.; Gerlag, P. G. G.; Gorgels, J. P. M. C.; Huisman, R. M.; Jager, K. J.; Jie, K.; Koning-Mulder, W. A. H.; Koolen, M. I.; Kremer Hovinga, T. K.; Lavrijssen, A. T. J.; Luik, A. J.; van der Meulen, J.; Parlevliet, K. J.; Raasveld, M. H. M.; van der Sande, F. M.; Schonck, M. J. M.; Schuurmans, M. M. J.; Siegert, C. E. H.; Stegeman, C. A.; Stevens, P.; Thijssen, J. G. P.; Valentijn, R. M.; Vastenburg, G. H.; Verburgh, C. A.; Vincent, H. H.; Vos, P. F.

    2011-01-01

    Despite a lack of strong evidence, automated peritoneal dialysis (APD) is often prescribed on account of an expected better quality of life (QoL) than that expected with continuous ambulatory peritoneal dialysis (CAPD). Our aim was to analyze differences in QoL in patients starting dialysis on APD

  13. Equilibrium and non-equilibrium phenomena in arcs and torches

    NARCIS (Netherlands)

    Mullen, van der J.J.A.M.

    2000-01-01

    A general treatment of non-equilibrium plasma aspects is obtained by relating transport fluxes to equilibrium restoring processes in so-called disturbed Bilateral Relations. The (non) equilibrium stage of a small microwave induced plasma serves as case study.

  14. Dialysis-associated steal syndrome (DASS).

    Science.gov (United States)

    Mohamed, Ahmed S; Peden, Eric K

    2017-03-06

    In this article, we will review the clinical symptoms of dialysis access steal syndrome (DASS), evaluation, treatment options, and our approach and treatment algorithm. We reviewed the literature discussing different aspects of DASS including its epidemiology, pathogenesis, clinical presentation, evaluation and management options. DASS is the most dreaded complication of access surgery. Although the incidence is low, all providers caring for dialysis patients should be aware of this problem. Symptoms can range from mild to limb threatening. Although various tests are available, the diagnosis of DASS remains a clinical one and requires thoughtful management to have the best outcomes. Multiple treatment options exist for steal. We present diagnostic evaluation and management algorithm.

  15. Wearable impedance monitoring system for dialysis patients.

    Science.gov (United States)

    Bonnet, S; Bourgerette, A; Gharbi, S; Rubeck, C; Arkouche, W; Massot, B; McAdams, E; Montalibet, A; Jallon, P

    2016-08-01

    This paper describes the development and the validation of a prototype wearable miniaturized impedance monitoring system for remote monitoring in home-based dialysis patients. This device is intended to assess the hydration status of dialysis patients using calf impedance measurements. The system is based on the low-power AD8302 component. The impedance calibration procedure is described together with the Cole parameter estimation and the hydric volume estimation. Results are given on a test cell to validate the design and on preliminary calf measurements showing Cole parameter variations during hemodialysis.

  16. Dialysis-related amyloidosis: challenges and solutions

    Directory of Open Access Journals (Sweden)

    Scarpioni R

    2016-12-01

    Full Text Available R Scarpioni, M Ricardi, V Albertazzi, S De Amicis, F Rastelli, L Zerbini Department of Nephrology and Dialysis, Azienda Unità Sanitaria Local (AUSL Hospital “Guglielmo da Saliceto”, Piacenza, Italy Abstract: Amyloidosis refers to the extracellular tissue deposition of fibrils composed of low-molecular-weight subunits of a variety of proteins. These deposits may result in a wide range of clinical manifestations depending upon their type, location, and the amount of deposition. Dialysis-related amyloidosis is a serious complication of long-term dialysis therapy and is characterized by the deposition of amyloid fibrils, principally composed of β2 microglobulins (β2M, in the osteoarticular structures and viscera. Most of the β2M is eliminated through glomerular filtration and subsequent reabsorption and catabolism by the proximal tubules. As a consequence, the serum levels of β2M are inversely related to the glomerular filtration rate; therefore, in end-stage renal disease patients, β2M levels increase up to 60-fold. Serum levels of β2M are also elevated in several pathological conditions such as chronic inflammation, liver disease, and above all, in renal dysfunction. Retention of amyloidogenic protein has been attributed to several factors including type of dialysis membrane, prolonged uremic state and/or decreased diuresis, advanced glycation end products, elevated levels of cytokines and dialysate. Dialysis treatment per se has been considered to be an inflammatory stimulus, inducing cytokine production (such as interleukin-1, tumor necrosis factor-α, interleukin-6 and complement activation. The released cytokines are thought to stimulate the synthesis and release of β2M by the macrophages and/or augment the expression of human leukocyte antigens (class I, increasing β2M expression. Residual renal function is probably the best determinant of β2M levels. Therefore, it has to be maintained as long as possible. In this article

  17. Neutron scattering on equilibrium and nonequilibrium phonons, excitons and polaritons

    International Nuclear Information System (INIS)

    Broude, V.L.; Sheka, E.F.

    1978-01-01

    A number of problems of solid-state physics representing interest for neutron spectroscopy of future is considered. The development of the neutron inelastic scattering spectroscopy (neutron spectroscopy of equilibrium phonons) is discussed with application to nuclear dynamics of crystals in the thermodynamic equilibrium. The results of high-flux neutron source experiments on molecular crystals are presented. The advantages of neutron inelastic scattering over optical spectroscopy are discussed. The spectroscopy of quasi-equilibrium and non-equilibrium quasi-particles is discussed. In particular, the neutron scattering on polaritons, excitons in thermal equilibrium and production of light-excitons are considered. The problem of the possibility of such experiments is elucidated

  18. Non-equilibrium Economics

    Directory of Open Access Journals (Sweden)

    Katalin Martinás

    2007-02-01

    Full Text Available A microeconomic, agent based framework to dynamic economics is formulated in a materialist approach. An axiomatic foundation of a non-equilibrium microeconomics is outlined. Economic activity is modelled as transformation and transport of commodities (materials owned by the agents. Rate of transformations (production intensity, and the rate of transport (trade are defined by the agents. Economic decision rules are derived from the observed economic behaviour. The non-linear equations are solved numerically for a model economy. Numerical solutions for simple model economies suggest that the some of the results of general equilibrium economics are consequences only of the equilibrium hypothesis. We show that perfect competition of selfish agents does not guarantee the stability of economic equilibrium, but cooperativity is needed, too.

  19. DIAGNOSIS OF FINANCIAL EQUILIBRIUM

    Directory of Open Access Journals (Sweden)

    SUCIU GHEORGHE

    2013-04-01

    Full Text Available The analysis based on the balance sheet tries to identify the state of equilibrium (disequilibrium that exists in a company. The easiest way to determine the state of equilibrium is by looking at the balance sheet and at the information it offers. Because in the balance sheet there are elements that do not reflect their real value, the one established on the market, they must be readjusted, and those elements which are not related to the ordinary operating activities must be eliminated. The diagnosis of financial equilibrium takes into account 2 components: financing sources (ownership equity, loaned, temporarily attracted. An efficient financial equilibrium must respect 2 fundamental requirements: permanent sources represented by ownership equity and loans for more than 1 year should finance permanent needs, and temporary resources should finance the operating cycle.

  20. Equilibrium statistical mechanics

    CERN Document Server

    Mayer, J E

    1968-01-01

    The International Encyclopedia of Physical Chemistry and Chemical Physics, Volume 1: Equilibrium Statistical Mechanics covers the fundamental principles and the development of theoretical aspects of equilibrium statistical mechanics. Statistical mechanical is the study of the connection between the macroscopic behavior of bulk matter and the microscopic properties of its constituent atoms and molecules. This book contains eight chapters, and begins with a presentation of the master equation used for the calculation of the fundamental thermodynamic functions. The succeeding chapters highlight t

  1. Computing Equilibrium Chemical Compositions

    Science.gov (United States)

    Mcbride, Bonnie J.; Gordon, Sanford

    1995-01-01

    Chemical Equilibrium With Transport Properties, 1993 (CET93) computer program provides data on chemical-equilibrium compositions. Aids calculation of thermodynamic properties of chemical systems. Information essential in design and analysis of such equipment as compressors, turbines, nozzles, engines, shock tubes, heat exchangers, and chemical-processing equipment. CET93/PC is version of CET93 specifically designed to run within 640K memory limit of MS-DOS operating system. CET93/PC written in FORTRAN.

  2. MHD equilibrium identification on ASDEX-Upgrade

    International Nuclear Information System (INIS)

    McCarthy, P.J.; Schneider, W.; Lakner, K.; Zehrfeld, H.P.; Buechl, K.; Gernhardt, J.; Gruber, O.; Kallenbach, A.; Lieder, G.; Wunderlich, R.

    1992-01-01

    A central activity accompanying the ASDEX-Upgrade experiment is the analysis of MHD equilibria. There are two different numerical methods available, both using magnetic measurements which reflect equilibrium states of the plasma. The first method proceeds via a function parameterization (FP) technique, which uses in-vessel magnetic measurements to calculate up to 66 equilibrium parameters. The second method applies an interpretative equilibrium code (DIVA) for a best fit to a different set of magnetic measurements. Cross-checks with the measured particle influxes from the inner heat shield and the divertor region and with visible camera images of the scrape-off layer are made. (author) 3 refs., 3 figs

  3. Removal of cobalt ion from bentonite using diffusion dialysis

    International Nuclear Information System (INIS)

    Takase, Hisao; Tamura, Kouichi; Katoh, Naotake

    1995-01-01

    A radioactive metal ion must be removed from contaminated soil which accidentally adsorbs the radioactive metal ion. With this situation, the authors examined the diffusion dialysis as a removal process of the radioactive ion from fine particles of the soil. In a dialyzer, the one side of the solution including fine particles of soil was referred to as diluting cell and the other side stripping was referred to as concentrating cell. The experiments by batch operations were carried out by interposing a cation exchange membrane (CMV) between both cells. The high separation of the ion from the soil could be achieved by the experiments when the aqueous solution of hydrochloric acid was used as stripping solution. Equations for batch diffusion dialysis system were set up and calculated. From the results of simulation, it was noted that the concentration of hydrochloric acid in the stripping solution, the selections of the membrane, and mass transfer coefficient at the surface of the membrane strongly affect the removal efficiency of the ion. (author)

  4. Exploring the association between macroeconomic indicators and dialysis mortality.

    Science.gov (United States)

    Kramer, Anneke; Stel, Vianda S; Caskey, Fergus J; Stengel, Benedicte; Elliott, Robert F; Covic, Adrian; Geue, Claudia; Cusumano, Ana; Macleod, Alison M; Jager, Kitty J

    2012-10-01

    Mortality on dialysis varies greatly worldwide, with patient-level factors explaining only a small part of this variation. The aim of this study was to examine the association of national-level macroeconomic indicators with the mortality of incident dialysis populations and explore potential explanations through renal service indicators, incidence of dialysis, and characteristics of the dialysis population. Aggregated unadjusted survival probabilities were obtained from 22 renal registries worldwide for patients starting dialysis in 2003-2005. General population age and health, macroeconomic indices, and renal service organization data were collected from secondary sources and questionnaires. Linear modeling with log-log transformation of the outcome variable was applied to establish factors associated with survival on dialysis. Two-year survival on dialysis ranged from 62.3% in Iceland to 89.8% in Romania. A higher gross domestic product per capita (hazard ratio=1.02 per 1000 US dollar increase), a higher percentage of gross domestic product spent on healthcare (1.10 per percent increase), and a higher intrinsic mortality of the dialysis population (i.e., general population-derived mortality risk of the dialysis population in that country standardized for age and sex; hazard ratio=1.04 per death per 10,000 person years) were associated with a higher mortality of the dialysis population. The incidence of dialysis and renal service indicators were not associated with mortality on dialysis. Macroeconomic factors and the intrinsic mortality of the dialysis population are associated with international differences in the mortality on dialysis. Renal service organizational factors and incidence of dialysis seem less important.

  5. Non-Equilibrium Properties from Equilibrium Free Energy Calculations

    Science.gov (United States)

    Pohorille, Andrew; Wilson, Michael A.

    2012-01-01

    Calculating free energy in computer simulations is of central importance in statistical mechanics of condensed media and its applications to chemistry and biology not only because it is the most comprehensive and informative quantity that characterizes the eqUilibrium state, but also because it often provides an efficient route to access dynamic and kinetic properties of a system. Most of applications of equilibrium free energy calculations to non-equilibrium processes rely on a description in which a molecule or an ion diffuses in the potential of mean force. In general case this description is a simplification, but it might be satisfactorily accurate in many instances of practical interest. This hypothesis has been tested in the example of the electrodiffusion equation . Conductance of model ion channels has been calculated directly through counting the number of ion crossing events observed during long molecular dynamics simulations and has been compared with the conductance obtained from solving the generalized Nernst-Plank equation. It has been shown that under relatively modest conditions the agreement between these two approaches is excellent, thus demonstrating the assumptions underlying the diffusion equation are fulfilled. Under these conditions the electrodiffusion equation provides an efficient approach to calculating the full voltage-current dependence routinely measured in electrophysiological experiments.

  6. The Green Dialysis Survey: Establishing a Baseline for Environmental Sustainability across Dialysis Facilities in Victoria, Australia.

    Science.gov (United States)

    Barraclough, Katherine A; Gleeson, Alice; Holt, Stephen G; Agar, John Wm

    2017-11-02

    The Green Dialysis Survey aimed to 1) establish a baseline for environmental sustainability (ES) across Victorian dialysis facilities, and 2) guide future initiatives to reduce the environmental impact of dialysis delivery. Nurse unit managers of all Victorian public dialysis facilities received an online link to the survey, which asked 107 questions relevant to the ES of dialysis services. Responses were received from 71/83 dialysis facilities in Victoria (86%), representing 628/660 dialysis chairs (95%). Low energy lighting was present in 13 facilities (18%), 18 (25%) recycled reverse osmosis water and 7 (10%) reported use of renewable energy. Fifty-six facilities (79%) performed comingled recycling but only 27 (38%) recycled polyvinyl chloride plastic. A minority educated staff in appropriate waste management (n=30;42%) or formally audited waste generation and segregation (n=19;27%). Forty-four (62%) provided secure bicycle parking but only 33 (46%) provided shower and changing facilities. There was limited use of tele- or video-conferencing to replace staff meetings (n=19;27%) or patient clinic visits (n=13;18%). A minority considered ES in procurement decisions (n=28;39%) and there was minimal preparedness to cope with climate change. Only 39 services (49%) confirmed an ES policy and few had ever formed a green group (n=14; 20%) or were currently undertaking a green project (n=8;11%). Only 15 facilities (21%) made formal efforts to raise awareness of ES. This survey provides a baseline for practices that potentially impact the environmental sustainability of dialysis units in Victoria, Australia. It also identifies achievable targets for attention. This article is protected by copyright. All rights reserved.

  7. The diagnosis of tuberculosis in dialysis patients

    Directory of Open Access Journals (Sweden)

    Hela Jebali

    2017-01-01

    Full Text Available The incidence of tuberculosis (TB is high in patients undergoing chronic dialysis than it is in the general population. The diagnosis of TB is often difficult and extrapulmonary involvement is predominant. This study investigates the spectrum of clinical presentations and outcome in dialysis patients during a nine-year period. TB was diagnosed in 41 patients. Anti-TB drugs, adverse effects of therapy, and outcome were noted. Thirty-eight patients (92.6% were on hemodialysis and three were on peritoneal dialysis (7.3%. The mean age at diagnosis was 50.8 years and the male/female ratio was 1.16. Four patients had a history of pulmonary TB. Extrapulmonary involvement was observed in 32 (78 % patients. The bacteriological confirmation was made in 41.46% and histological confirmation was made in 26.83%, and in the rest, the diagnosis was retained on the criterion presumption. Nineteen patients (46.34% developed adverse effects of antitubercular drugs. Eight patients (19.51% died during the study from TB or adverse effects of treatment. Low urea reduction ratio and female sex were associated with poor prognosis in our study. The clinical manifestations of TB in patients on dialysis are quite nonspecific, making timely diagnosis difficult, and delaying the initiation of curative treatment, which is a major determinant of the outcome.

  8. The Manchester contribution to peritoneal dialysis

    NARCIS (Netherlands)

    Krediet, Raymond T.

    2011-01-01

    Two names emerge when considering the contribution of Manchester in the development of peritoneal dialysis (PD). The first is Ram Gokal; the second is icodextrin. As there will be a separate article on icodextrin, this one will focus more on other aspects of the activities performed by the Renal

  9. Fungal peritonitis in children on peritoneal dialysis.

    NARCIS (Netherlands)

    Raaijmakers, R.; Schroder, C.; Monnens, L.A.H.; Cornelissen, E.A.M.; Warris, A.

    2007-01-01

    Fungal peritonitis is a rare but serious complication in children on peritoneal dialysis (PD). In this study, risk factors were evaluated, and therapeutic measures were reviewed. A retrospective, multi-centre study was performed in 159 Dutch paediatric PD patients, between 1980 and 2005 (3,573

  10. [Evaluation of methods to calculate dialysis dose in daily hemodialysis].

    Science.gov (United States)

    Maduell, F; Gutiérrez, E; Navarro, V; Torregrosa, E; Martínez, A; Rius, A

    2003-01-01

    Daily dialysis has shown excellent clinical results because a higher frequency of dialysis is more physiological. Different methods have been described to calculate dialysis dose which take into consideration change in frequency. The aim of this study was to calculate all dialysis dose possibilities and evaluate the better and practical options. Eight patients, 6 males and 2 females, on standard 4 to 5 hours thrice weekly on-line hemodiafiltration (S-OL-HDF) were switched to daily on-line hemodiafiltration (D-OL-HDF) 2 to 2.5 hours six times per week. Dialysis parameters were identical during both periods and only frequency and dialysis time of each session were changed. Time average concentration (TAC), time average deviation (TAD), normalized protein catabolic rate (nPCR), Kt/V, equilibrated Kt/V (eKt/V), equivalent renal urea clearance (EKR), standard Kt/V (stdKt/V), urea reduction ratio (URR), hemodialysis product and time off dialysis were measured. Daily on-line hemodiafiltration was well accepted and tolerated. Patients maintained the same TAC although TAD decreased from 9.7 +/- 2 in baseline to a 6.2 +/- 2 mg/dl after six months, p time off dialysis was reduced to half. Dialysis frequency is an important urea kinetic parameter which there are to take in consideration. It's necessary to use EKR, stdKt/V or weekly URR to calculate dialysis dose for an adequate comparison between different frequency dialysis schedules.

  11. Small angle neutron scattering (SANS) under non-equilibrium conditions

    International Nuclear Information System (INIS)

    Oberthur, R.C.

    1984-01-01

    The use of small angle neutron scattering (SANS) for the study of systems under non-equilibrium conditions is illustrated by three types of experiments in the field of polymer research: - the relaxation of a system from an initial non-equilibrium state towards equilibrium, - the cyclic or repetitive installation of a series of non-equilibrium states in a system, - the steady non-equilibrium state maintained by a constant dissipation of energy within the system. Characteristic times obtained in these experiments with SANS are compared with the times obtained from quasi-elastic neutron and light scattering, which yield information about the equilibrium dynamics of the system. The limits of SANS applied to non-equilibrium systems for the measurement of relaxation times at different length scales are shown and compared to the limits of quasielastic neutron and light scattering

  12. Immunity by equilibrium.

    Science.gov (United States)

    Eberl, Gérard

    2016-08-01

    The classical model of immunity posits that the immune system reacts to pathogens and injury and restores homeostasis. Indeed, a century of research has uncovered the means and mechanisms by which the immune system recognizes danger and regulates its own activity. However, this classical model does not fully explain complex phenomena, such as tolerance, allergy, the increased prevalence of inflammatory pathologies in industrialized nations and immunity to multiple infections. In this Essay, I propose a model of immunity that is based on equilibrium, in which the healthy immune system is always active and in a state of dynamic equilibrium between antagonistic types of response. This equilibrium is regulated both by the internal milieu and by the microbial environment. As a result, alteration of the internal milieu or microbial environment leads to immune disequilibrium, which determines tolerance, protective immunity and inflammatory pathology.

  13. Thermal equilibrium in Einstein's elevator.

    Science.gov (United States)

    Sánchez-Rey, Bernardo; Chacón-Acosta, Guillermo; Dagdug, Leonardo; Cubero, David

    2013-05-01

    We report fully relativistic molecular-dynamics simulations that verify the appearance of thermal equilibrium of a classical gas inside a uniformly accelerated container. The numerical experiments confirm that the local momentum distribution in this system is very well approximated by the Jüttner function-originally derived for a flat spacetime-via the Tolman-Ehrenfest effect. Moreover, it is shown that when the acceleration or the container size is large enough, the global momentum distribution can be described by the so-called modified Jüttner function, which was initially proposed as an alternative to the Jüttner function.

  14. Coassembly of Lysozyme and Amphiphilic Biomolecules Driven by Unimer-Aggregate Equilibrium.

    Science.gov (United States)

    Tao, Yuanyuan; Ma, Xiaoteng; Cai, Yaqian; Liu, Li; Zhao, Hanying

    2018-04-12

    Synthesis and self-assembly of bioconjugates composed of proteins and synthetic molecules have been widely studied because of the potential applications in medicine, biotechnology, and nanotechnology. One of the challenging research studies in this area is to develop organic solvent-free approaches to the synthesis and self-assembly of amphiphilic bioconjugates. In this research, dialysis-assisted approach, a method based on unimer-aggregate equilibrium, was applied in the coassembly of lysozyme and conjugate of cholesterol and glutathione (Ch-GSH). In phosphate buffer solution, amphiphilic Ch-GSH conjugate self-assembles into vesicles, and the vesicle solution is dialyzed against lysozyme solution. Negatively charged Ch-GSH unimers produced in the unimer-vesicle exchange equilibrium, diffuse across the dialysis membrane and have electrostatic interaction with positively charged lysozyme, resulting in the formation of Ch-GSH-lysozyme bioconjugate. Above a critical concentration, the three-component bioconjugate molecules self-assemble into bioactive vesicles.

  15. Equilibrium shoreface profiles

    DEFF Research Database (Denmark)

    Aagaard, Troels; Hughes, Michael G

    2017-01-01

    Large-scale coastal behaviour models use the shoreface profile of equilibrium as a fundamental morphological unit that is translated in space to simulate coastal response to, for example, sea level oscillations and variability in sediment supply. Despite a longstanding focus on the shoreface...... profile and its relevance to predicting coastal response to changing environmental conditions, the processes and dynamics involved in shoreface equilibrium are still not fully understood. Here, we apply a process-based empirical sediment transport model, combined with morphodynamic principles to provide......; there is no tuning or calibration and computation times are short. It is therefore easily implemented with repeated iterations to manage uncertainty....

  16. Biofeedback-driven dialysis: where are we?

    Science.gov (United States)

    Santoro, Antonio; Ferramosca, Emiliana; Mancini, Elena

    2008-01-01

    The progressive increase in the mean age and the growing conditions of co-morbidity, especially of cardiovascular pathologies and diabetes, have significantly worsened the patients' clinical status and tolerance to the hemodialysis (HD) treatment. On the other hand, the demand for short treatment times enhances the risk for hemodynamic instability as well as for inadequate depuration. The traditional management of the dialysis session, setting of predefined treatment parameters, with active therapeutic interventions only in the event of complications, is definitely unsuitable for short-lasting treatments, often complicated by hemodynamic instability, especially in critical patients. The first step to improve the management of the dialysis session is the utilization of continuous and uninvasive monitoring systems for hemodynamic or biochemical parameters involved in the dialysis quality. Special sensors for the continuous measurement of blood volume, blood temperature, blood pressure, heart rate, electrolytes, have been realized throughout the last 10 years. As a second step, some of these devices have been implemented in the dialysis instrumentation, mainly with a view to preventing cardiocirculatory instability but also to control the dialysis efficiency (biofeedback control systems). The basic components of a biofeedback system are: the plant, the sensors, the actuators and the controller. The plant is the biological process that we need to control, while the sensors are the devices used for measuring the output variables. The actuators are the working arms of the controller. The controller is the mathematical model that continuously sets the measured output variable against the reference input and modifies the actuators in order to reduce any discrepancies. Yet, in practice there are a number of conceptual, physical and technological difficulties to be overcome. In particular, the behavior of what is to be controlled may be non-linear and time-varying, with

  17. A call to arms: economic barriers to optimal dialysis care.

    Science.gov (United States)

    McFarlane, P A; Mendelssohn, D C

    2000-01-01

    Epidemic growth rates and the enormous cost of dialysis pressure end-stage renal disease (ESRD) delivery systems around the world. Payers of dialysis services can constrain costs through (1) limiting access to dialysis, (2) reducing the quality of dialysis, and (3) placing constraints on modality distribution. In order to secure the necessary resources for ESRD care, we propose that the nephrology community consider the following suggestions: First, future leaders in dialysis should acquire additional advanced training in innovative pathways such as health care economics, business and health care administration, and health care policy. Second, the international nephrology community must strongly engage in ongoing advocacy for accessible, high quality, cost-effective care.Third, efforts should be made to better define and then implement optimal dialysis modality distributions that maximize patient outcomes but limit unnecessary costs. Fourth, industry should be encouraged to lower the unit cost of dialysis, allowing for improved access to dialysis, especially in developing countries. Fifth, research should be encouraged that seeks to identify measures that will reduce dialysis costs but will not impair quality of care. Finally, early referral of patients with progressive renal disease to nephrology clinics, empowerment of informed patient choice of dialysis modality, and proper and timely access creation should be encouraged and can be expected to help limit overall expenditures. Ongoing efforts in these areas by the nephrology community will be essential if we are to overcome the challenges of ESRD growth in this new decade.

  18. Dialysis and Quality of Dialysate in Southeast Asian Developing Countries

    Directory of Open Access Journals (Sweden)

    Tomotaka Naramura

    2014-04-01

    Full Text Available Background: The number of dialysis patients has been increasing in Southeast Asia, but statistical data about these patients and on the quality of dialysates in Southeast Asian dialysis facilities are still imprecise. For this study, dialysis-related statistical data were collected in Southeast Asia. Methods: A survey of the quality of dialysates was carried out at 4 dialysis facilities in Vietnam and Cambodia. The dialysis patient survey included the numbers of dialysis facilities and patients receiving dialysis, a ranking of underlying diseases causing the initiation of dialysis, the number of patients receiving hemodialysis (HD/on-line hemodiafiltration/continuous ambulatory peritoneal dialysis, the number of HD monitoring devices installed, the cost of each session of dialysis (in USD, the percentage of out-of-pocket payments, and the 1-year survival rates of the dialysis patients (in percent. The dialysate survey covered the endotoxin (ET level and bacterial count in tap water, in water filtered through a reverse osmosis system and in dialysate. Results: In each of the countries, the most frequent reason for the initiation of dialysis is diabetes mellitus. HD is usually carried out according to the ‘reuse' principle. The 1-year survival rates are 70% in Myanmar and about 90% in the Philippines and Malaysia. The ET levels in standard dialysates were satisfactory at 2 facilities. The bacterial counts in dialysates were not acceptable at any of the facilities investigated. Conclusion: There is an urgent need to teach medical workers involved in dialysis how to prepare sterile and ET-free dialysates.

  19. Microeconomics : Equilibrium and Efficiency

    NARCIS (Netherlands)

    Ten Raa, T.

    2013-01-01

    Microeconomics: Equilibrium and Efficiency teaches how to apply microeconomic theory in an innovative, intuitive and concise way. Using real-world, empirical examples, this book not only covers the building blocks of the subject, but helps gain a broad understanding of microeconomic theory and

  20. Differential Equation of Equilibrium

    African Journals Online (AJOL)

    user

    ABSTRACT. Analysis of underground circular cylindrical shell is carried out in this work. The forth order differential equation of equilibrium, comparable to that of beam on elastic foundation, was derived from static principles on the assumptions of P. L Pasternak. Laplace transformation was used to solve the governing ...

  1. Comments on equilibrium, transient equilibrium, and secular equilibrium in serial radioactive decay

    International Nuclear Information System (INIS)

    Prince, J.R.

    1979-01-01

    Equations describing serial radioactive decay are reviewed along with published descriptions or transient and secular equilibrium. It is shown that terms describing equilibrium are not used in the same way by various authors. Specific definitions are proposed; they suggest that secular equilibrium is a subset of transient equilibrium

  2. A prime determinant in selecting dialysis modality: peritoneal dialysis patient survival

    Directory of Open Access Journals (Sweden)

    Hyunwook Kim

    2017-03-01

    Full Text Available The number of patients with end-stage renal disease (ESRD has rapidly increased, as has the cost of dialysis. Peritoneal dialysis (PD is an established treatment for ESRD patients worldwide; it has a variety of advantages, including autonomy and flexibility, as well as economic benefits in many countries compared to hemodialysis (HD. However, the long-term survival rate of PD remains poor. Although direct comparison of survival rate between the dialysis modalities by randomized controlled trials is difficult due to the ethical issues, it has always been a crucial point when deciding which dialysis modality should be recommended to patients. Recently, in many countries, including the United States, Brazil, Spain, Australia, and New Zealand, the survival rate in PD patients has significantly improved. PD patient survival in Korea has also improved, but Korean PD patients are known to have higher risk of mortality and major adverse cardiovascular, cerebrovascular events than HD patients. Herein, we further evaluate why Korean PD patients had worse outcomes; we suggest that special attention should be paid to patients with diabetes, coronary artery disease, or congestive heart failure when they choose PD as the first dialysis modality in order to reduce mortality risk.

  3. Capacitive Neutralization Dialysis for Direct Energy Generation.

    Science.gov (United States)

    Liu, Yue; Zhang, Yi; Ou-Yang, Wei; Bastos Sales, Bruno; Sun, Zhuo; Liu, Fei; Zhao, Ran

    2017-08-15

    Capacitive neutralization dialysis energy (CNDE) is proposed as a novel energy-harvesting technique that is able to utilize waste acid and alkaline solutions to produce electrical energy. CNDE is a modification based on neutralization dialysis. It was found that a higher NaCl concentration led to a higher open-circuit potential when the concentrations of acid and alkaline solutions were fixed. Upon closing of the circuit, the membrane potential was used as a driving force to move counter ions into the electrical double layers at the electrode-liquid interface, thereby creating an ionic current. Correspondingly, in the external circuit, electrons flow through an external resistor from one electrode to the other, thereby generating electrical energy directly. The influence of external resistances was studied to achieve greater energy extraction, with the maximum output of 110 mW/m 2 obtained by employing an external resistance of 5 Ω together with the AC-coated electrode.

  4. Dialysis Provision and Implications of Health Economics on Peritoneal Dialysis Utilization: A Review from a Malaysian Perspective.

    Science.gov (United States)

    Abdul Manaf, Mohd Rizal; Surendra, Naren Kumar; Abdul Gafor, Abdul Halim; Seong Hooi, Lai; Bavanandan, Sunita

    2017-01-01

    End-stage renal disease (ESRD) is managed by either lifesaving hemodialysis (HD) and peritoneal dialysis (PD) or a kidney transplant. In Malaysia, the prevalence of dialysis-treated ESRD patients has shown an exponential growth from 504 per million population (pmp) in 2005 to 1155 pmp in 2014. There were 1046 pmp patients on HD and 109 pmp patients on PD in 2014. Kidney transplants are limited due to lack of donors. Malaysia adopts public-private financing model for dialysis. Majority of HD patients were treated in the private sector but almost all PD patients were treated in government facilities. Inequality in access to dialysis is visible within geographical regions where majority of HD centres are scattered around developed areas. The expenditure on dialysis has been escalating in recent years but economic evaluations of dialysis modalities are scarce. Evidence shows that health policies and reimbursement strategies influence dialysis provision. Increased uptake of PD can produce significant economic benefits and improve patients' access to dialysis. As a result, some countries implemented a PD-First or Favored Policy to expand PD use. Thus, a current comparative costs analysis of dialysis is strongly recommended to assist decision-makers to establish a more equitable and economically sustainable dialysis provision in the future.

  5. Dialysis Provision and Implications of Health Economics on Peritoneal Dialysis Utilization: A Review from a Malaysian Perspective

    Directory of Open Access Journals (Sweden)

    Mohd Rizal Abdul Manaf

    2017-01-01

    Full Text Available End-stage renal disease (ESRD is managed by either lifesaving hemodialysis (HD and peritoneal dialysis (PD or a kidney transplant. In Malaysia, the prevalence of dialysis-treated ESRD patients has shown an exponential growth from 504 per million population (pmp in 2005 to 1155 pmp in 2014. There were 1046 pmp patients on HD and 109 pmp patients on PD in 2014. Kidney transplants are limited due to lack of donors. Malaysia adopts public-private financing model for dialysis. Majority of HD patients were treated in the private sector but almost all PD patients were treated in government facilities. Inequality in access to dialysis is visible within geographical regions where majority of HD centres are scattered around developed areas. The expenditure on dialysis has been escalating in recent years but economic evaluations of dialysis modalities are scarce. Evidence shows that health policies and reimbursement strategies influence dialysis provision. Increased uptake of PD can produce significant economic benefits and improve patients’ access to dialysis. As a result, some countries implemented a PD-First or Favored Policy to expand PD use. Thus, a current comparative costs analysis of dialysis is strongly recommended to assist decision-makers to establish a more equitable and economically sustainable dialysis provision in the future.

  6. Single Pass Albumin Dialysis in Hepatorenal Syndrome

    Directory of Open Access Journals (Sweden)

    Rahman Ebadur

    2008-01-01

    Full Text Available Hepatorenal syndrome (HRS is the most appalling complication of acute or chronic liver disease with 90% mortality rate. Single pass albumin dialysis (SPAD can be considered as a noble liver support technique in HRS. Here, we present a case of a young healthy patient who developed hyperacute fulminant liver failure that progressed to HRS. The patient was offered SPAD as a bridge to liver transplantation, however, it resulted in an excellent recovery.

  7. Sacroiliac pain in a dialysis patient

    Science.gov (United States)

    Tristano, Antonio G

    2009-01-01

    The case is reported of a 47-year-old man with a history of chronic renal failure, treated with peritoneal dialysis, who presented with acute sacroiliac joint pain secondary to a pelvic abscess. Initially a diagnosis of infectious sacroiliitis of the left sacroiliac joint was suspected, but following investigation a pain referable to the sacroiliac joint was suspected. The patient recovered with a combination of antibiotics for the pelvic abscess and non-steroidal anti-inflammatory drugs. PMID:21994518

  8. Counter-flow dialysis for microvolume desalting

    OpenAIRE

    Kalikavunkal, Prameen Chacko

    2015-01-01

    Some analytical techniques are not compatible with physiological salt concentrations. An array of desalting approaches exists, but the conventional implementation requires large sample volumes, which is not compatible with fingerprick blood samples for molecular diagnostics. With dialysis being identified as the most suitable method for on-chip microvolume desalting, the aim of this work was to develop a microvolume dialyser that can desalt biological samples to any required salt concentratio...

  9. Waste acid recycling via diffusion dialysis

    Energy Technology Data Exchange (ETDEWEB)

    Steffani, C.

    1995-05-26

    Inorganic acids are commonly used for surface cleaning and finishing of metals. The acids become unuseable due to contamination with metals or diluted and weakened. Diffusion dialysis has become a way to recover the useable acid and allow separation of the metals for recovery and sale to refineries. This technique is made possible by the use of membranes that are strong enough to withstand low ph and have long service life.

  10. Satisfaction with care in peritoneal dialysis patients.

    Science.gov (United States)

    Kirchgessner, J; Perera-Chang, M; Klinkner, G; Soley, I; Marcelli, D; Arkossy, O; Stopper, A; Kimmel, P L

    2006-10-01

    Patient satisfaction is an important aspect of dialysis care, only recently evaluated in clinical studies. We developed a tool to assess peritoneal dialysis (PD) customer satisfaction, and sought to evaluate and validate the Customer Satisfaction Questionnaire (CSQ), quantifying PD patient satisfaction. The CSQ included questions regarding administrative issues, Delivery Service, PD Training, Handling Requests, and transportation. The study was performed using interviews in all Hungarian Fresenius Medical Care dialysis centers offering PD. CSQ results were compared with psychosocial measures to identify if patient satisfaction was associated with perception of social support and illness burden, or depression. We assessed CSQ internal consistency and validity. Factor analysis explored potential underlying dimensions of the CSQ. One hundred and thirty-three patients treated with PD for end-stage renal disease for more than 3 months were interviewed. The CSQ had high internal consistency. There was high patient satisfaction with customer service. PD patient satisfaction scores correlated with quality of life (QOL) and social support measures, but not with medical or demographic factors, or depressive affect. The CSQ is a reliable tool to assess PD customer satisfaction. PD patient satisfaction is associated with perception of QOL. Efforts to improve customer satisfaction may improve PD patients' quantity as well as QOL.

  11. Peritoneal dialysis in acute renal failure in canines: A review

    Directory of Open Access Journals (Sweden)

    R. H. Bhatt

    Full Text Available Peritoneal dialysis is a technique whereby infusion of dialysis solution into the peritoneal cavity is followed by a variable dwell time and subsequent drainage. During peritoneal dialysis, solutes and fluids are exchanged between the capillary blood and the intraperitoneal fluid through a biologic membrane, the peritoneum. Inadequate renal function leads to disturbance in the removal of the extra fluid and waste products. It removes the waste product and extra fluid from the body in renal failure in small animal practice. Peritoneal dialysis is more accessible, more affordable and easier to administer to the small animal patient. The most common indication for peritoneal dialysis in dogs is acute renal failure (ARF. Peritoneal dialysis is an important therapeutic tool for mitigating clinical signs of uremia and giving the kidneys time to recover in cats with acute kidney injury when conventional therapy is no longer effective. [Vet. World 2011; 4(11.000: 517-521

  12. Spatial Analysis of Case-Mix and Dialysis Modality Associations.

    Science.gov (United States)

    Phirtskhalaishvili, Tamar; Bayer, Florian; Edet, Stephane; Bongiovanni, Isabelle; Hogan, Julien; Couchoud, Cécile

    2016-01-01

    ♦ Health-care systems must attempt to provide appropriate, high-quality, and economically sustainable care that meets the needs and choices of patients with end-stage renal disease (ESRD). France offers 9 different modalities of dialysis, each characterized by dialysis technique, the extent of professional assistance, and the treatment site. The aim of this study was 1) to describe the various dialysis modalities in France and the patient characteristics associated with each of them, and 2) to analyze their regional patterns to identify possible unexpected associations between case-mixes and dialysis modalities. ♦ The clinical characteristics of the 37,421 adult patients treated by dialysis were described according to their treatment modality. Agglomerative hierarchical cluster analysis was used to aggregate the regions into clusters according to their use of these modalities and the characteristics of their patients. ♦ The gradient of patient characteristics was similar from home hemodialyis (HD) to in-center HD and from non-assisted automated peritoneal dialysis (APD) to assisted continuous ambulatory peritoneal dialysis (CAPD). Analyzing their spatial distribution, we found differences in the patient case-mix on dialysis across regions but also differences in the health-care provided for them. The classification of the regions into 6 different clusters allowed us to detect some unexpected associations between case-mixes and treatment modalities. ♦ The 9 modalities of treatment available make it theoretically possible to adapt treatment to patients' clinical characteristics and abilities. However, although we found an overall appropriate association of dialysis modalities to the case-mix, major inter-region heterogeneity and the low rate of peritoneal dialysis (PD) and home HD suggest that factors besides patients' clinical conditions impact the choice of dialysis modality. The French organization should now be evaluated in terms of patients' quality of

  13. Benfotiamine Protects against Peritoneal and Kidney Damage in Peritoneal Dialysis

    OpenAIRE

    Kihm, Lars P.; Müller-Krebs, Sandra; Klein, Julia; Ehrlich, Gregory; Mertes, Laura; Gross, Marie-Luise; Adaikalakoteswari, Antonysunil; Thornalley, Paul J.; Hammes, Hans-Peter; Nawroth, Peter P.; Zeier, Martin; Schwenger, Vedat

    2011-01-01

    Residual renal function and the integrity of the peritoneal membrane contribute to morbidity and mortality among patients treated with peritoneal dialysis. Glucose and its degradation products likely contribute to the deterioration of the remnant kidney and damage to the peritoneum. Benfotiamine decreases glucose-induced tissue damage, suggesting the potential for benefit in peritoneal dialysis. Here, in a model of peritoneal dialysis in uremic rats, treatment with benfotiamine decreased peri...

  14. Water soluble vitamins and peritoneal dialysis - State of the art.

    Science.gov (United States)

    Jankowska, Magdalena; Lichodziejewska-Niemierko, Monika; Rutkowski, Bolesław; Dębska-Ślizień, Alicja; Małgorzewicz, Sylwia

    2017-12-01

    This review presents the results of a systematic literature search concerning water soluble vitamins and peritoneal dialysis modality. We provide an overview of the data available on vitamin requirements, dietary intake, dialysis related losses, metabolism and the benefits of supplementation. We also summarise the current recommendations concerning the supplementation of vitamins in peritoneal dialysis and discuss the safety of an administration of vitamins in pharmacological doses. Copyright © 2016 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

  15. Equilibrium and pre-equilibrium emissions in proton-induced ...

    Indian Academy of Sciences (India)

    necessary for the domain of fission-reactor technology for the calculation of nuclear transmutation ... tions occur in three stages: INC, pre-equilibrium and equilibrium (or compound. 344. Pramana ... In the evaporation phase of the reaction, the.

  16. Factors Affecting Hemodialysis Patients' Satisfaction with Their Dialysis Therapy

    Directory of Open Access Journals (Sweden)

    M. Al Eissa

    2010-01-01

    Full Text Available Aim. To assess the degree of satisfaction among hemodialysis patients and the factors influencing this satisfaction. Methods. Patients were recruited from 3 Saudi dialysis centers. Demographic data was collected. Using 1 to 10 Likert scale, the patients were asked to rate the overall satisfaction with, and the overall impact of, their dialysis therapy on their lives and to rate the effect of the dialysis therapy on 15 qualities of life domains. Results. 322 patients were recruited (72.6% of the total eligible patients. The mean age was 51.7 years (±15.4; 58% have been on dialysis for >3 years. The mean Charlson Comorbidity Index was 3.2 (±2, and Kt/V was 1.3 (±0.44. The mean satisfaction score was (7.41 ± 2.75 and the mean score of the impact of the dialysis on the patients' lives was 5.32 ± 2.55. Male patients reported worse effect of dialysis on family life, social life, energy, and appetite. Longer period since the commencement of dialysis was associated with adverse effect on finances and energy. Lower level of education was associated with worse dialysis effect on stress, overall health, sexual life, hobbies, and exercise ability. Conclusion. The level of satisfaction is affected by gender, duration on dialysis, educational level, and standard of care given.

  17. Effects of Physician Payment Reform on Provision of Home Dialysis

    Science.gov (United States)

    Erickson, Kevin F.; Winkelmayer, Wolfgang C.; Chertow, Glenn M.; Bhattacharya, Jay

    2016-01-01

    Objectives Patients with end-stage renal disease can receive dialysis at home or in-center. In 2004 the Centers for Medicare and Medicaid Services reformed physician payment for in-center hemodialysis care from a capitated to a tiered fee-for-service model, augmenting physician payment for frequent in-center visits. We evaluated whether payment reform influenced dialysis modality assignment. Study Design Cohort study of patients starting dialysis in the US in the three years before and after payment reform. Methods We conducted difference-in-difference analyses comparing patients with Traditional Medicare coverage (who were affected by the policy) to others with Medicare Advantage (who were unaffected by the policy). We also examined whether the policy had a more pronounced influence on dialysis modality assignment in areas with lower costs of traveling to dialysis facilities. Results Patients with Traditional Medicare coverage experienced a 0.7% (95% CI 0.2%–1.1%; p=0.003) reduction in the absolute probability of home dialysis use following payment reform compared to patients with Medicare Advantage. Patients living in areas with larger dialysis facilities (where payment reform made in-center hemodialysis comparatively more lucrative for physicians) experienced a 0.9% (95% CI 0.5%–1.4%; ppayment model for dialysis care resulted in fewer patients receiving home dialysis. This area of policy failure highlights the importance of considering unintended consequences of future physician payment reform efforts. PMID:27355909

  18. Peritoneal dialysis-related peritonitis: challenges and solutions

    Science.gov (United States)

    Salzer, William L

    2018-01-01

    Peritoneal dialysis is an effective treatment modality for patients with end-stage renal disease. The relative use of peritoneal dialysis versus hemodialysis varies widely by country. Data from a 2004 survey reports the percentage of patients with end-stage renal disease treated with peritoneal dialysis to be 5%–10% in economically developed regions like the US and Western Europe to as much as 75% in Mexico. This disparity is probably related to the availability and access to hemodialysis, or in some cases patient preference for peritoneal over hemodialysis. Peritoneal dialysis-related peritonitis remains the major complication and primary challenge to the long-term success of peritoneal dialysis. Fifty years ago, with the advent of the Tenckhoff catheter, patients averaged six episodes of peritonitis per year on peritoneal dialysis. In 2016, the International Society for Peritoneal Dialysis proposed a benchmark of 0.5 episodes of peritonitis per year or one episode every 2 years. Despite the marked reduction in peritonitis over time, peritonitis for the individual patient is problematic. The mortality for an episode of peritonitis is 5% and is a cofactor for mortality in another 16% of affected patients. Prevention of peritonitis and prompt and appropriate management of peritonitis is essential for the long-term success of peritoneal dialysis in all patients. In this review, challenges and solutions are addressed regarding the pathogenesis, clinical features, diagnosis, treatment, and prevention of peritoneal dialysis-related peritonitis from the viewpoint of an infectious disease physician.

  19. Protein binding of glufosinate and factors affecting it revealed by an equilibrium dialysis technique.

    Science.gov (United States)

    Hori, Y; Koyama, K; Fujisawa, M; Nakajima, M; Shimada, K; Hirose, Y; Kohda, Y; Akuzawa, H

    2001-09-01

    We investigated the protein binding of glufosinate ammonium (GLF) and several factors affecting this binding using human serum albumin (HSA) and human volunteer serum under various conditions. The mean ratios of the free GLF (RFr-GLF) to 4% HSA were examined in the sera of patients described elsewhere at GLF levels from 1 microg/mL to 500 microg/mL; the range was found to be only from 0.80 to 0.88. Neither the incubation temperature nor buffers containing different chloride ion concentrations had any effect on the RFr-GLF to HSA. Moreover, the addition of heparin, glycoprotein-alpha1-acid (AAG), and sodium azide had no effect on the RFr-GLF. However, pH of the isotonic phosphate buffer and the addition of palmitic or oleic acid were seen to have an effect. In this study, the mean RFr-GLF to healthy human serum was 0.99. This high value was evidenced that GLF was rapidly excreted through the renal route.

  20. Melanin binding study of clinical drugs with cassette dosing and rapid equilibrium dialysis inserts

    OpenAIRE

    Pelkonen L; Tengvall-Unadike U; Ruponen M; Kidron H; del Amo EM; Reinisalo M; Urtti A

    2017-01-01

    Melanin pigment is a negatively charged polymer found in pigmented human tissues. In the eye, iris, ciliary body, choroid and retinal pigment epithelium (RPE) are heavily pigmented. Several drug molecules are known to bind to melanin, but larger sets of drugs have not been compared often in similar test conditions. In this study, we introduce a powerful tool for screening of melanin binding. The binding of a set of 34 compounds to isolated porcine RPE melanin was determined by cassette (n-in-...

  1. Lactic acidosis in the rectal lumen of patients with septic shock measured by luminal equilibrium dialysis

    DEFF Research Database (Denmark)

    Due, V; Bonde, J; Espersen, K

    2002-01-01

    Gut ischaemia may contribute to morbidity in sepsis, but little is known about the metabolic state of the gut mucosa in such patients.......Gut ischaemia may contribute to morbidity in sepsis, but little is known about the metabolic state of the gut mucosa in such patients....

  2. Equilibrium and non-equilibrium metal-ceramic interfaces

    International Nuclear Information System (INIS)

    Gao, Y.; Merkle, K.L.

    1992-01-01

    Metal-ceramic interfaces in thermodynamic equilibrium (Au/ZrO 2 ) and non-equilibrium (Au/MgO) have been studied by TEM and HREM. In the Au/ZrO 2 system, ZrO 2 precipitates formed by internal oxidation of a 7%Zr-Au alloy show a cubic ZrO 2 phase. It appears that formation of the cubic ZrO 2 is facilitated by alignment with the Au matrix. Most of the ZrO 2 precipitates have a perfect cube-on-cube orientation relationship with the Au matrix. The large number of interfacial steps observed in a short-time annealing experiment indicate that the precipitates are formed by the ledge growth mechanism. The lowest interfacial energy is indicated by the dominance of closed-packed [111] Au/ZrO 2 interfaces. In the Au/MgO system, composite films with small MgO smoke particles embedded in a Au matrix were prepared by a thin film technique. HREM observations show that most of the Au/MgO interfaces have a strong tendency to maintain a dense lattice structure across the interfaces irrespective of whether the interfaces are incoherent or semi-coherent. This paper reports that this indicates that there may be a relatively strong bond between MgO and Au

  3. Periodic Peritoneal Dialysis in End Stage Renal Disease: Is it Still ...

    African Journals Online (AJOL)

    peritoneal dialysis (PD) in India has made renal replacement therapy out of reach of many patients with ... Keywords: Peritoneal dialysis, End stage renal disease, Renal replacement therapy ..... adherence to the dialysis program is often poor.

  4. Gated equilibrium bloodpool scintigraphy

    International Nuclear Information System (INIS)

    Reinders Folmer, S.C.C.

    1981-01-01

    This thesis deals with the clinical applications of gated equilibrium bloodpool scintigraphy, performed with either a gamma camera or a portable detector system, the nuclear stethoscope. The main goal has been to define the value and limitations of noninvasive measurements of left ventricular ejection fraction as a parameter of cardiac performance in various disease states, both for diagnostic purposes as well as during follow-up after medical or surgical intervention. Secondly, it was attempted to extend the use of the equilibrium bloodpool techniques beyond the calculation of ejection fraction alone by considering the feasibility to determine ventricular volumes and by including the possibility of quantifying valvular regurgitation. In both cases, it has been tried to broaden the perspective of the observations by comparing them with results of other, invasive and non-invasive, procedures, in particular cardiac catheterization, M-mode echocardiography and myocardial perfusion scintigraphy. (Auth.)

  5. Problems in equilibrium theory

    CERN Document Server

    Aliprantis, Charalambos D

    1996-01-01

    In studying General Equilibrium Theory the student must master first the theory and then apply it to solve problems. At the graduate level there is no book devoted exclusively to teaching problem solving. This book teaches for the first time the basic methods of proof and problem solving in General Equilibrium Theory. The problems cover the entire spectrum of difficulty; some are routine, some require a good grasp of the material involved, and some are exceptionally challenging. The book presents complete solutions to two hundred problems. In searching for the basic required techniques, the student will find a wealth of new material incorporated into the solutions. The student is challenged to produce solutions which are different from the ones presented in the book.

  6. Equilibrium statistical mechanics

    CERN Document Server

    Jackson, E Atlee

    2000-01-01

    Ideal as an elementary introduction to equilibrium statistical mechanics, this volume covers both classical and quantum methodology for open and closed systems. Introductory chapters familiarize readers with probability and microscopic models of systems, while additional chapters describe the general derivation of the fundamental statistical mechanics relationships. The final chapter contains 16 sections, each dealing with a different application, ordered according to complexity, from classical through degenerate quantum statistical mechanics. Key features include an elementary introduction t

  7. Volatility in Equilibrium

    DEFF Research Database (Denmark)

    Bollerslev, Tim; Sizova, Natalia; Tauchen, George

    Stock market volatility clusters in time, carries a risk premium, is fractionally inte- grated, and exhibits asymmetric leverage effects relative to returns. This paper develops a first internally consistent equilibrium based explanation for these longstanding empirical facts. The model is cast i......, and the dynamic cross-correlations of the volatility measures with the returns calculated from actual high-frequency intra-day data on the S&P 500 aggregate market and VIX volatility indexes....

  8. Molecular equilibrium with condensation

    International Nuclear Information System (INIS)

    Sharp, C.M.; Huebner, W.F.

    1990-01-01

    Minimization of the Gibbs energy of formation for species of chemical elements and compounds in their gas and condensed phases determines their relative abundances in a mixture in chemical equilibrium. The procedure is more general and more powerful than previous abundance determinations in multiphase astrophysical mixtures. Some results for astrophysical equations of state are presented, and the effects of condensation on opacity are briefly indicated. 18 refs

  9. Equilibrium calculations, ch. 6

    International Nuclear Information System (INIS)

    Deursen, A.P.J. van

    1976-01-01

    A calculation is presented of dimer intensities obtained in supersonic expansions. There are two possible limiting considerations; the dimers observed are already present in the source, in thermodynamic equilibrium, and are accelerated in the expansion. Destruction during acceleration is neglected, as are processes leading to newly formed dimers. On the other hand one can apply a kinetic approach, where formation and destruction processes are followed throughout the expansion. The difficulty of this approach stems from the fact that the density, temperature and rate constants have to be known at all distances from the nozzle. The simple point of view has been adopted and the measured dimer intensities are compared with the equilibrium concentration in the source. The comparison is performed under the assumption that the detection efficiency for dimers is twice the detection efficiency for monomers. The experimental evidence against the simple point of view that the dimers of the onset region are formed in the source already, under equilibrium conditions, is discussed. (Auth.)

  10. Noncompact Equilibrium Points and Applications

    Directory of Open Access Journals (Sweden)

    Zahra Al-Rumaih

    2012-01-01

    Full Text Available We prove an equilibrium existence result for vector functions defined on noncompact domain and we give some applications in optimization and Nash equilibrium in noncooperative game.

  11. Equilibrium thermodynamics - Callen's postulational approach

    NARCIS (Netherlands)

    Jongschaap, R.J.J.; Öttinger, Hans Christian

    2001-01-01

    In order to provide the background for nonequilibrium thermodynamics, we outline the fundamentals of equilibrium thermodynamics. Equilibrium thermodynamics must not only be obtained as a special case of any acceptable nonequilibrium generalization but, through its shining example, it also elucidates

  12. MHD equilibrium with toroidal rotation

    International Nuclear Information System (INIS)

    Li, J.

    1987-03-01

    The present work attempts to formulate the equilibrium of axisymmetric plasma with purely toroidal flow within ideal MHD theory. In general, the inertial term Rho(v.Del)v caused by plasma flow is so complicated that the equilibrium equation is completely different from the Grad-Shafranov equation. However, in the case of purely toroidal flow the equilibrium equation can be simplified so that it resembles the Grad-Shafranov equation. Generally one arbitrary two-variable functions and two arbitrary single variable functions, instead of only four single-variable functions, are allowed in the new equilibrium equations. Also, the boundary conditions of the rotating (with purely toroidal fluid flow, static - without any fluid flow) equilibrium are the same as those of the static equilibrium. So numerically one can calculate the rotating equilibrium as a static equilibrium. (author)

  13. Laparoscopic Placement of Peritoneal Dialysis Catheters in CAPD Patients: Complications and Survival

    Directory of Open Access Journals (Sweden)

    A Roueentan

    2008-06-01

    Full Text Available Background: Laparoscopic techniques for the placement of peritoneal dialysis catheters are becoming increasingly popular. Recently, with the improvements in laparoscopic surgery, various methods for the insertion of peritoneal dialysis catheters have been reported, indicating that the laparoscopic insertion is preferred over the open and percutaneous techniques. The aim of this study was to introduce and assess a simplified laparoscopic method for the insertion of peritoneal dialysis catheters in continuous ambulatory peritoneal dialysis (CAPD patients.Methods: We enrolled 79 consecutive end-stage renal patients (46 men and 33 women with a mean age of 50 years (range: 19-83 years in this study. During the surgery, a 5-mm trocar was placed in the left upper quadrant for the optics and another 5-mm trocar was placed to the left of the umbilicus. Using the second trocar, a tunnel was formed 2 cm left of the umbilical plane for the insertion of a Tenckhoff catheter. Under direct vision, the catheter was advanced into the abdomen. The catheter was tested for patency. Catheters of all subjects were capped for two weeks before dialysis initiation.Results: The mean duration of the operation was 15 minutes. Ten patients died during the follow-up period, all due to other medical problems, and six patients underwent renal transplantation; however, no deaths or complications were observed during surgery. Early onset complications were seen in 12 patients (15.1%. The most frequent late-onset medical and mechanical complications were peritonitis (6.3% and hernia (3.7%. During a follow-up period of four years, removal of the catheter was required in two patients as a result of peritonitis.Conclusion: We obtained a low complication rate and a high catheter survival rate with this laparoscopic insertion of the Tenckhoff catheter. We believe future experience will encourage the use of this safe, simple and quick procedure.

  14. Estimating Equilibrium Effects of Job Search Assistance

    DEFF Research Database (Denmark)

    Gautier, Pieter; Muller, Paul; van der Klaauw, Bas

    that the nonparticipants in the experiment regions find jobs slower after the introduction of the activation program (relative to workers in other regions). We then estimate an equilibrium search model. This model shows that a large scale role out of the activation program decreases welfare, while a standard partial...... microeconometric cost-benefit analysis would conclude the opposite....

  15. Decreasing dialysis catheter rates by creating a multidisciplinary dialysis access program.

    Science.gov (United States)

    Rosenberry, Patricia M; Niederhaus, Silke V; Schweitzer, Eugene J; Leeser, David B

    2018-03-01

    Centers for Medicare and Medicaid Services have determined that chronic dialysis units should have 45%. A multidisciplinary program was established with goals of decreasing catheter rates in order to decrease central line-associated bloodstream infections, decrease mortality associated with central line-associated bloodstream infection, decrease hospital days, and provide savings to the healthcare system. We collected the catheter rates within three dialysis centers served over a 5-year period. Using published data surrounding the incidence and related costs of central line-associated bloodstream infection and mortality per catheter day, the number of central line-associated bloodstream infection events, the costs, and the related mortality could be determined prior to and after the initiation of the dialysis access program. An organized dialysis access program resulted in a 82% decrease in the number of central venous catheter days which lead to a concurrent reduction in central line-associated bloodstream infection and deaths. As a result of creating an access program, central venous catheter rates decreased from an average rate of 45% to 8%. The cost savings related to the program was calculated to be over US$5 million. The decrease in the number of mortalities is estimated to be between 13 and 27 patients. We conclude that a formalized access program decreases catheter rates, central line-associated bloodstream infection, and the resultant hospitalizations, mortality, and costs. Areas with high hemodialysis catheter rates should develop access programs to better serve their patient population.

  16. Comparative Analysis of Serum Levels of Aluminum and Lead in Dialysis Patients, Pre and post Dialysis

    Directory of Open Access Journals (Sweden)

    Atieh Makhlough

    2014-05-01

    Conclusion: Trace elements status in chronic kidney diseases patients is influenced by a renal function residual, size and dialyzer membrane surface. The water nature also is used for dialysis fluid preparation and composition. Trace elements in ESRD patients differed from healthy individuals. So this issue requires accurate studies on trace elements clinical aspects in ESRD patients.

  17. Protein A affinity chromatography of Chinese hamster ovary (CHO) cell culture broths containing biopharmaceutical monoclonal antibody (mAb): Experiments and mechanistic transport, binding and equilibrium modeling.

    Science.gov (United States)

    Grom, Matic; Kozorog, Mirijam; Caserman, Simon; Pohar, Andrej; Likozar, Blaž

    2018-04-15

    Protein A-based affinity chromatography is a highly-efficient separation method to capture, purify and isolate biosimilar monoclonal antibodies (mAb) - an important medical product of biopharmaceutical industrial manufacturing. It is considered the most expensive step in purification downstream operations; therefore, its performance optimization offers a great cost saving in the overall production expenditure. The biochemical mixture-separating specific interaction experiments with Chinese hamster ovary (CHO) cell culture harvest, containing glycosylated extracellular immunoglobulins (Ig), were made using five different state-of-the-art commercial resins. Packing breakthrough curves were recorded at an array of prolonged residence times. A mathematical simulation model was developed, applied and validated in combination with non-linear regression algorithms on bed effluent concentrations to determine the previously-unknown binding properties of stationary phase materials. Apart from the columns' differential partitioning, the whole external system was also integrated. It was confirmed that internal pore diffusion is the global rate-limiting resistance of the compound retention process. Immobilizing substrate characteristics, obtained in this engineering study, are indispensable for the scale-up of the periodic counter-current control with mechanistic load, elution and wash reduction. Furthermore, unit's volumetric flow screening measurements revealed dynamic effect correlation to eluate quality parameters, like the presence of aggregates, the host cell-related impurities at supernatant's extended feeding, and titre. Numerical sensitivity outputs demonstrated the impacts of fluidics (e.g. axial dispersion coefficient), thermodynamics (Langmuir adsorption) and mass transfer fluxes. Copyright © 2018 Elsevier B.V. All rights reserved.

  18. Peritoneal dialysis: a primary care perspective.

    Science.gov (United States)

    Saxena, Ramesh; West, Cheryl

    2006-01-01

    As the population of chronic kidney disease (CKD) and end-stage renal disease (ESRD) grows at an alarming rate, primary care physicians will increasingly be involved in the management of these patients. Early recognition of CKD and timely referral to a nephrologist when glomerular filtration rate approaches 30 mL/min/1.73 m(2) is extremely important to improve ESRD outcome and appropriate selection of dialysis modality. Peritoneal dialysis (PD) remains a viable treatment option for ESRD patients. PD is less expensive dialysis modality and may provide a survival advantages over hemodialysis in first 2 to 4 years of treatment. Preserving residual renal function (RRF) is of paramount importance to prolong the survival outcomes in PD patients. Thus preservation of RRF is an important goal in the management of PD patients. Every effort should be made to avoid nephrotoxic drugs like aminoglycosides and nonsteroidal anti-inflammatory drugs, and limit the use of radiocontrast agents in PD patients with RRF. Judicious use of prophylactic antibiotics to prevent peritonitis would further help to reduce morbidity from PD. Protecting peritoneal membrane from long-term toxic and metabolic effects of the conventional glucose-based solutions is another objective to further improve PD outcome. Development of new, more biocompatible PD solutions holds promise for the future. One such solution, icodextrin, is now approved for use in the United States. Although extremely safe to use, it is associated with unique metabolic effects that may concern primary care physicians. They include false elevation of blood glucose, a reversible increase in serum alkaline phosphatase and a false decline in serum amylase. Monitoring of glycemia by assays that use glucose dehydrogenase pyrroloquinoline quinone enzymes should be avoided and serum amylase alone should not be relied on in diagnosing pancreatitis in patients on icodextrin.

  19. Entropy of uremia and dialysis technology.

    Science.gov (United States)

    Ronco, Claudio

    2013-01-01

    The second law of thermodynamics applies with local exceptions to patient history and therapy interventions. Living things preserve their low level of entropy throughout time because they receive energy from their surroundings in the form of food. They gain their order at the expense of disordering the nutrients they consume. Death is the thermodynamically favored state: it represents a large increase in entropy as molecular structure yields to chaos. The kidney is an organ dissipating large amounts of energy to maintain the level of entropy of the organism as low as possible. Diseases, and in particular uremia, represent conditions of rapid increase in entropy. Therapeutic strategies are oriented towards a reduction in entropy or at least a decrease in the speed of entropy increase. Uremia is a process accelerating the trend towards randomness and disorder (increase in entropy). Dialysis is a factor external to the patient that tends to reduce the level of entropy caused by kidney disease. Since entropy can only increase in closed systems, energy and work must be spent to limit the entropy of uremia. This energy should be adapted to the system (patient) and be specifically oriented and personalized. This includes a multidimensional effort to achieve an adequate dialysis that goes beyond small molecular weight solute clearance. It includes a biological plan for recovery of homeostasis and a strategy towards long-term rehabilitation of the patient. Such objectives can be achieved with a combination of technology and innovation to answer specific questions that are still present after 60 years of dialysis history. This change in the individual bioentropy may represent a local exception to natural trends as the patient could be considered an isolated universe responding to the classic laws of thermodynamics. Copyright © 2013 S. Karger AG, Basel.

  20. [Peritonitis in pediatric patients receiving peritoneal dialysis].

    Science.gov (United States)

    Jellouli, Manel; Ferjani, Meriem; Abidi, Kamel; Hammi, Yosra; Boutiba, Ilhem; Naija, Ouns; Zarrouk, Chokri; Ben Abdallah, Taieb; Gargah, Tahar

    2015-12-01

    Peritonitis on catheter of dialysis represents the most frequent complication of the peritoneal dialysis (PD) in the pediatric population. It remains a significant cause of morbidity and mortality. In this study, we investigated the risk factors for peritonitis in children. In this study, we retrospectively collected the records of 85 patients who were treated with PD within the past ten years in the service of pediatrics of the University Hospital Charles-Nicolle of Tunis. Peritonitis rate was 0.75 episode per patient-year. Notably, peritonitis caused by Gram-positive organisms were more common. Analysis of infection risk revealed three significant independent factors: the poor weight (P=0.0045), the non-automated PD (P=0.02) and the short delay from catheter insertion to starting PD (P=0.02). The early onset peritonitis was significantly associated with frequent peritonitis episodes (P=0.0008). The mean duration between the first and second episode of peritonitis was significantly shorter than between PD commencement and the first episode of peritonitis. We revealed a significant association between Gram-negative peritonitis and the presence of ureterostomy (0.018) and between Gram-positive peritonitis and the presence of exit-site and tunnel infections (0.02). Transition to permanent hemodialysis was needed in many children but no death occurred in patients with peritonitis. Considering the important incidence of peritonitis in our patients, it is imperative to establish a targeted primary prevention. Nutritional care must be provided to children to avoid poor weight. The automated dialysis has to be the modality of choice. Copyright © 2015 Association Société de néphrologie. Published by Elsevier SAS. All rights reserved.

  1. Unusual dialysate leakage complicating peritoneal dialysis

    International Nuclear Information System (INIS)

    Chiu, Jainn-Shiun; Yu, Fu-Chiu; Chen, Chiou-An; Wang, Yuh-Feng

    2006-01-01

    A 16-year-old female who had end-stage renal disease on 2-month continuous ambulatory peritoneal dialysis (CAPD) presented with perineal pain 4 days before admission. The physical examination revealed bilateral labial edema. Peritoneal scintigraphy was requested after infusing 2 L peritoneal dialysate with direct administration of 370 MBq (10mCi) technetium-99m diethylenetriamine pentra-acetic acid into peritoneal cavity via Tenckhoff catheter. Radioactive uptake from right inguinal to labial region was clearly demonstrated, and this indicated the site of peritoneal leakage. After surgical intervention unilaterally, she continued CAPD without any recurrence (au)

  2. Neurological complications of renal dialysis and transplantation.

    Science.gov (United States)

    Karunaratne, Kushan; Taube, David; Khalil, Nofal; Perry, Richard; Malhotra, Paresh A

    2018-04-01

    Neurological complications from renal replacement therapy contribute significantly to morbidity and mortality in patients with renal failure. Such complications can affect either the central or peripheral nervous systems. Most neurological disturbances associated with the uraemic state do not respond fully to renal replacement therapy. There are also complications specifically associated with dialysis and transplantation. A multidisciplinary approach, involving both nephrologists and neurologists, is critical for the diagnosis and effective management of these disorders. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  3. Non-equilibrium thermodynamics

    CERN Document Server

    De Groot, Sybren Ruurds

    1984-01-01

    The study of thermodynamics is especially timely today, as its concepts are being applied to problems in biology, biochemistry, electrochemistry, and engineering. This book treats irreversible processes and phenomena - non-equilibrium thermodynamics.S. R. de Groot and P. Mazur, Professors of Theoretical Physics, present a comprehensive and insightful survey of the foundations of the field, providing the only complete discussion of the fluctuating linear theory of irreversible thermodynamics. The application covers a wide range of topics: the theory of diffusion and heat conduction, fluid dyn

  4. Acute hydrothorax complicating peritoneal dialysis: a case report

    Directory of Open Access Journals (Sweden)

    Ranganathan Dwarkanathan

    2010-11-01

    Full Text Available Abstract Introduction Acute hydrothorax is an uncommon but a well-recognized complication of peritoneal dialysis. No single test is definitive for diagnosis. Although it is not a life-threatening condition, hydrothorax often requires abandonment of peritoneal dialysis. Delay in diagnosis can lead to worsening of the clinical status. Case Presentation A 33-year-old Caucasian woman with lupus, who was successfully treated with temporary peritoneal dialysis 17 years previously, presented with acute dyspnea and a right pleural effusion after recommencing peritoneal dialysis. Investigations eliminated infective, cardiac, and primary respiratory causes. Peritoneal dialysis-related hydrothorax was suggested by biochemistry, and a pleuroperitoneal leak was definitively confirmed by using a Tc-99 m DTPA (diethylene triamine penta-acetic acid scintigraphy scan. Subsequently, she underwent video-assisted thoracoscopy-guided talc pleurodesis and was able to return successfully to peritoneal dialysis. Conclusion Although our case is not the first report that describes the occurrence of acute hydrothorax in peritoneal dialysis, it is an important condition to recognize for the wider general medical community. Furthermore, this case demonstrates that peritoneal dialysis can be continued with a hydrothorax, provided the underlying cause can be corrected. We review the literature pertaining to the utility and reliability of different diagnostic approaches to hydrothorax.

  5. Cardiovascular and noncardiovascular mortality among patients starting dialysis

    DEFF Research Database (Denmark)

    de Jager, Dinanda J; Grootendorst, Diana C; Jager, Kitty J

    2009-01-01

    CONTEXT: Cardiovascular mortality is considered the main cause of death in patients receiving dialysis and is 10 to 20 times higher in such patients than in the general population. OBJECTIVE: To evaluate if high overall mortality in patients starting dialysis is a consequence of increased cardiov...

  6. Haemodialysis at home: review of current dialysis machines.

    Science.gov (United States)

    Haroon, Sabrina; Davenport, Andrew

    2018-04-26

    Only a minority of patients with chronic kidney disease treated by hemodialysis are currently treated at home. Until relatively recently, the only type of hemodialysis machine available for these patients was a slightly smaller version of the standard machines used for in-center dialysis treatments. Areas covered: There are now an alternative generation of dialysis machines specifically designed for home hemodialysis. The home dialysis patient wants a smaller machine, which is intuitive to use, easy to trouble shoot, robust and reliable, quick to setup and put away, requiring minimal waste disposal. The machines designed for home dialysis have some similarities in terms of touch-screen patient interfaces, and using pre-prepared cartridges to speed up setting up the machine. On the other hand, they differ in terms of whether they use slower or standard dialysate flows, prepare batches of dialysis fluid, require separate water purification equipment, or whether this is integrated, or use pre-prepared sterile bags of dialysis fluid. Expert commentary: Dialysis machine complexity is one of the hurdles reducing the number of patients opting for home hemodialysis and the introduction of the newer generation of dialysis machines designed for ease of use will hopefully increase the number of patients opting for home hemodialysis.

  7. Risk factors for peritoneal dialysis catheter failure in children ...

    African Journals Online (AJOL)

    Background Peritoneal dialysis catheter (PDC) failure still remains a common clinical problem in pediatric patients despite advancements in catheter placement and dialysis techniques. Our aim was to determine the risk factors that may lead to PDC failure, especially those factors that could be potentially modified to ...

  8. Predictors of chain acquisition among independent dialysis facilities.

    Science.gov (United States)

    Pozniak, Alyssa S; Hirth, Richard A; Banaszak-Holl, Jane; Wheeler, John R C

    2010-04-01

    To determine the predictors of chain acquisition among independent dialysis providers. Retrospective facility-level data combined from CMS Cost Reports, Medical Evidence Forms, Annual Facility Surveys, and claims for 1996-2003. Independent dialysis facilities' probability of acquisition by a dialysis chain (overall and by chain size) was estimated using a discrete time hazard rate model, controlling for financial and clinical performance, practice patterns, market factors, and other facility characteristics. The sample includes all U.S. freestanding dialysis facilities that report not being chain affiliated for at least 1 year between 1997 and 2003. Above-average costs and better quality outcomes are significant determinants of dialysis chain acquisition. Facilities in larger markets were more likely to be acquired by a chain. Furthermore, small dialysis chains have different acquisition strategies than large chains. Dialysis chains appear to employ a mix of turn-around and cream-skimming strategies. Poor financial health is a predictor of chain acquisition as in other health care sectors, but the increased likelihood of chain acquisition among higher quality facilities is unique to the dialysis industry. Significant differences among predictors of acquisition by small and large chains reinforce the importance of using a richer classification for chain status.

  9. Patients in assisted automated peritoneal dialysis develop strategies for selfcare

    DEFF Research Database (Denmark)

    Holch, Kirsten

      Patients in Assisted Automated Peritoneal Dialysis develop strategies for self-care Background: Since 2000 a model for Assisted Automated Peritoneal Dialysis (AAPD) in the patients own home has been developed at Aarhus University Hospital, Skejby. The patient group consists of physically...

  10. Dialysis and renal transplantation in HIV-infected patients

    DEFF Research Database (Denmark)

    Trullas, Joan Carles; Mocroft, Amanda; Cofan, Federico

    2010-01-01

    To determine prevalence and characteristics of end-stage renal diseases (ESRD) [dialysis and renal transplantation (RT)] among European HIV-infected patients.......To determine prevalence and characteristics of end-stage renal diseases (ESRD) [dialysis and renal transplantation (RT)] among European HIV-infected patients....

  11. Module description of TOKAMAK equilibrium code MEUDAS

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Masaei; Hayashi, Nobuhiko; Matsumoto, Taro; Ozeki, Takahisa [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

    2002-01-01

    The analysis of an axisymmetric MHD equilibrium serves as a foundation of TOKAMAK researches, such as a design of devices and theoretical research, the analysis of experiment result. For this reason, also in JAERI, an efficient MHD analysis code has been developed from start of TOKAMAK research. The free boundary equilibrium code ''MEUDAS'' which uses both the DCR method (Double-Cyclic-Reduction Method) and a Green's function can specify the pressure and the current distribution arbitrarily, and has been applied to the analysis of a broad physical subject as a code having rapidity and high precision. Also the MHD convergence calculation technique in ''MEUDAS'' has been built into various newly developed codes. This report explains in detail each module in ''MEUDAS'' for performing convergence calculation in solving the MHD equilibrium. (author)

  12. Computational studies in tokamak equilibrium and transport

    International Nuclear Information System (INIS)

    Braams, B.J.

    1986-01-01

    This thesis is concerned with some problems arising in the magnetic confinement approach to controlled thermonuclear fusion. The work address the numerical modelling of equilibrium and transport properties of a confined plasma and the interpretation of experimental data. The thesis is divided in two parts. Part 1 is devoted to some aspects of the MHD equilibrium problem, both in the 'direct' formulation (given an equation for the plasma current, the corresponding equilibrium is to be determined) and in the 'inverse' formulation (the interpretation of measurements at the plasma edge). Part 2 is devoted to numerical studies of the edge plasma. The appropriate Navier-Stokes system of fluid equations is solved in a two-dimensional geometry. The main interest of this work is to develop an understanding of particle and energy transport in the scrape-off layer and onto material boundaries, and also to contribute to the conceptual design of the NET/INTOR tokamak reactor experiment. (Auth.)

  13. Scaling studies of spheromak formation and equilibrium

    International Nuclear Information System (INIS)

    Geddes, C.G.; Kornack, T.W.; Brown, M.R.

    1998-01-01

    Formation and equilibrium studies have been performed on the Swarthmore Spheromak Experiment (SSX). Spheromaks are formed with a magnetized coaxial plasma gun and equilibrium is established in both small (d small =0.16 m) and large (d large =3d small =0.50 m) copper flux conservers. Using magnetic probe arrays it has been verified that spheromak formation is governed solely by gun physics (in particular the ratio of gun current to flux, μ 0 I gun /Φ gun ) and is independent of the flux conserver dimensions. It has also been verified that equilibrium is well described by the force free condition ∇xB=λB (λ=constant), particularly early in decay. Departures from the force-free state are due to current profile effects described by a quadratic function λ=λ(ψ). Force-free SSX spheromaks will be merged to study magnetic reconnection in simple magnetofluid structures. copyright 1998 American Institute of Physics

  14. Module description of TOKAMAK equilibrium code MEUDAS

    International Nuclear Information System (INIS)

    Suzuki, Masaei; Hayashi, Nobuhiko; Matsumoto, Taro; Ozeki, Takahisa

    2002-01-01

    The analysis of an axisymmetric MHD equilibrium serves as a foundation of TOKAMAK researches, such as a design of devices and theoretical research, the analysis of experiment result. For this reason, also in JAERI, an efficient MHD analysis code has been developed from start of TOKAMAK research. The free boundary equilibrium code ''MEUDAS'' which uses both the DCR method (Double-Cyclic-Reduction Method) and a Green's function can specify the pressure and the current distribution arbitrarily, and has been applied to the analysis of a broad physical subject as a code having rapidity and high precision. Also the MHD convergence calculation technique in ''MEUDAS'' has been built into various newly developed codes. This report explains in detail each module in ''MEUDAS'' for performing convergence calculation in solving the MHD equilibrium. (author)

  15. Determinants of Adherence to Living on Dialysis for Mexican Americans

    Directory of Open Access Journals (Sweden)

    Shirley A. Wells

    2015-03-01

    Full Text Available This study explores perceptions that affect adherence behaviors among Mexican Americans living with dialysis. In-depth narrative interviews were conducted with 15 Mexican Americans with end-stage renal disease (ESRD living on dialysis, 15 family members, and 6 health care personnel who provided care to them. Four themes emerged: (a positive influences to adherence, (b obstacles to adherence, (c daily activity losses, and (d fears about living with dialysis. From the findings, the perceptions given for non-adherence with the dialysis regimen ranged from denial of the condition, lack of pre-education, to cultural factors. Those given for adherence included prolonged life, family, and hope of getting a transplant. Health care providers were the reminder to adhere. Several cultural factors influenced their adherence perceptions. Strategies to enhance adherence behaviors should focus on knowledge about dialysis, use of the collective efficacy of the family, and the inclusion of cultural values.

  16. Psychosocial adjustment and adherence to dialysis treatment regimes.

    Science.gov (United States)

    Brownbridge, G; Fielding, D M

    1994-12-01

    Sixty children and adolescents in end-stage renal failure who were undergoing either haemodialysis or continuous ambulatory peritoneal dialysis at one of five United Kingdom dialysis centres were assessed on psychosocial adjustment and adherence to their fluid intake, diet and medication regimes. Parental adjustment was also measured and data on sociodemographic and treatment history variables collected. A structured family interview and standardised questionnaire measures of anxiety, depression and behavioural disturbance were used. Multiple measures of treatment adherence were obtained, utilising children's and parents' self-reports, weight gain between dialysis, blood pressure, serum potassium level, blood urea level, dietitians' surveys and consultants' ratings. Correlational analyses showed that low treatment adherence was associated with poor adjustment to diagnosis and dialysis by children and parents (P adherence than younger children, P dialysis (P treatment of this group of children. Future research should develop and evaluate psychosocial interventions aimed at improving treatment adherence.

  17. Differences in survival on chronic dialysis treatment between ethnic groups in Denmark: a population-wide, national cohort study.

    Science.gov (United States)

    van den Beukel, Tessa O; Hommel, Kristine; Kamper, Anne-Lise; Heaf, James G; Siegert, Carl E H; Honig, Adriaan; Jager, Kitty J; Dekker, Friedo W; Norredam, Marie

    2016-07-01

    In Western countries, black and Asian dialysis patients experience better survival compared with white patients. The aim of this study is to compare the survival of native Danish dialysis patients with that of dialysis patients originating from other countries and to explore the association between the duration of residence in Denmark before the start of dialysis and the mortality on dialysis. We performed a population-wide national cohort study of incident chronic dialysis patients in Denmark (≥18 years old) who started dialysis between 1995 and 2010. In total, 8459 patients were native Danes, 344 originated from other Western countries, 79 from North Africa or West Asia, 173 from South or South-East Asia and 54 from sub-Saharan Africa. Native Danes were more likely to die on dialysis compared with the other groups (crude incidence rates for mortality: 234, 166, 96, 110 and 53 per 1000 person-years, respectively). Native Danes had greater hazard ratios (HRs) for mortality compared with the other groups {HRs for mortality adjusted for sociodemographic and clinical characteristics: 1.32 [95% confidence interval (CI) 1.14-1.54]; 2.22 [95% CI 1.51-3.23]; 1.79 [95% CI 1.41-2.27]; 2.00 [95% CI 1.10-3.57], respectively}. Compared with native Danes, adjusted HRs for mortality for Western immigrants living in Denmark for ≤10 years, >10 to ≤20 years and >20 years were 0.44 (95% CI 0.27-0.71), 0.56 (95% CI 0.39-0.82) and 0.86 (95% CI 0.70-1.04), respectively. For non-Western immigrants, these HRs were 0.42 (95% CI 0.27-0.67), 0.52 (95% CI 0.33-0.80) and 0.48 (95% CI 0.35-0.66), respectively. Incident chronic dialysis patients in Denmark originating from countries other than Denmark have a better survival compared with native Danes. For Western immigrants, this survival benefit declines among those who have lived in Denmark longer. For non-Western immigrants, the survival benefit largely remains over time. © The Author 2015. Published by Oxford University Press on

  18. Thermal equilibrium of goats.

    Science.gov (United States)

    Maia, Alex S C; Nascimento, Sheila T; Nascimento, Carolina C N; Gebremedhin, Kifle G

    2016-05-01

    The effects of air temperature and relative humidity on thermal equilibrium of goats in a tropical region was evaluated. Nine non-pregnant Anglo Nubian nanny goats were used in the study. An indirect calorimeter was designed and developed to measure oxygen consumption, carbon dioxide production, methane production and water vapour pressure of the air exhaled from goats. Physiological parameters: rectal temperature, skin temperature, hair-coat temperature, expired air temperature and respiratory rate and volume as well as environmental parameters: air temperature, relative humidity and mean radiant temperature were measured. The results show that respiratory and volume rates and latent heat loss did not change significantly for air temperature between 22 and 26°C. In this temperature range, metabolic heat was lost mainly by convection and long-wave radiation. For temperature greater than 30°C, the goats maintained thermal equilibrium mainly by evaporative heat loss. At the higher air temperature, the respiratory and ventilation rates as well as body temperatures were significantly elevated. It can be concluded that for Anglo Nubian goats, the upper limit of air temperature for comfort is around 26°C when the goats are protected from direct solar radiation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Home Dialysis in the Prospective Payment System Era.

    Science.gov (United States)

    Lin, Eugene; Cheng, Xingxing S; Chin, Kuo-Kai; Zubair, Talhah; Chertow, Glenn M; Bendavid, Eran; Bhattacharya, Jayanta

    2017-10-01

    The ESRD Prospective Payment System introduced two incentives to increase home dialysis use: bundling injectable medications into a single payment for treatment and paying for home dialysis training. We evaluated the effects of the ESRD Prospective Payment System on home dialysis use by patients starting dialysis in the United States from January 1, 2006 to August 31, 2013. We analyzed data on dialysis modality, insurance type, and comorbidities from the United States Renal Data System. We estimated the effect of the policy on home dialysis use with multivariable logistic regression and compared the effect on Medicare Parts A/B beneficiaries with the effect on patients with other types of insurance. The ESRD Prospective Payment System associated with a 5.0% (95% confidence interval [95% CI], 4.0% to 6.0%) increase in home dialysis use by the end of the study period. Home dialysis use increased by 5.8% (95% CI, 4.3% to 6.9%) among Medicare beneficiaries and 4.1% (95% CI, 2.3% to 5.4%) among patients covered by other forms of health insurance. The difference between these groups was not statistically significant (1.8%; 95% CI, -0.2% to 3.8%). Conversely, in both populations, the training add-on did not associate with increases in home dialysis use beyond the effect of the policy. The ESRD Prospective Payment System bundling, but not the training add-on, associated with substantial increases in home dialysis, which were identical for both Medicare and non-Medicare patients. These spill-over effects suggest that major payment changes in Medicare can affect all patients with ESRD. Copyright © 2017 by the American Society of Nephrology.

  20. Refusal of dialysis amongst patients of chronic kidney disease (CKD)

    International Nuclear Information System (INIS)

    Anees, M.; Khan, J.A.

    2014-01-01

    This study was conducted to determine the refusal of dialysis amongst patients of chronic kidney disease presenting for the first time for dialysis in uremic condition. Study Design: Cross sectional Study. Place and Duration of the Study: Outpatient department of Nephrology, Mayo Hospital, Lahore from 1 st Jan 2012 to 31 st December 2012. Patients and Methods: Patients of CKD due to any cause presenting with uremia for the first time for dialysis were included in the study. History and physical examination was done and demographic data was collected in pre designed form. Patients were offered for dialysis while explaining to them the advantages of getting and disadvantages of not getting dialysis. Patient's response on the offer was recorded and the reason for the refusal were noted. Results: According to the criteria 150 patients were included in the study. Most of the patients were male 92 (61.3%) and illiterate 78 (52.0%). Major cause of CKD was diabetes mellitus 58 (38.7%) followed by hypertension 38 (25.3%). Mean age of the patients was 42.59 ± 13.72 year and income of themost of the patients 126 (84%) was less than US$100/-month. Most of the patients 126 (77.0%) were asked about the need of dialysis in less than three months, 61 (41.3%) offered for the first time and amongst them 85 (54.0%) were offered dialysis already. Majority of the patients 101 (67.3%) refused dialysis when it was offered to them for the first time. Major reason of the refusal was fear of dialysis procedure in 76 (76%) patients followed by treatment by spiritual 14 (14%) and alternative ways and others 11 (11 %). Middle age persons refused dialysis significantly. (author)

  1. Dialysis Malnutrition and Malnutrition Inflammation Scores: screening tools for prediction of dialysis-related protein-energy wasting in Malaysia.

    Science.gov (United States)

    Harvinder, Gilcharan Singh; Swee, Winnie Chee Siew; Karupaiah, Tilakavati; Sahathevan, Sharmela; Chinna, Karuthan; Ahmad, Ghazali; Bavanandan, Sunita; Goh, Bak Leong

    2016-01-01

    Malnutrition is highly prevalent in Malaysian dialysis patients and there is a need for a valid screening tool for early identification and management. This cross-sectional study aims to examine the sensitivity of the Dialysis Malnutrition Score (DMS) and Malnutrition Inflammation Score (MIS) tools in predicting protein-energy wasting (PEW) among Malaysian dialysis patients. A total of 155 haemodialysis (HD) and 90 peritoneal dialysis (PD) patients were screened for risk of malnutrition using DMS and MIS and comparisons were made with established guidelines by International Society of Renal Nutrition and Metabolism (ISRNM) for PEW. MIS cut-off score of >=5 indicated presence of malnutrition in all patients. A total of 59% of HD and 83% of PD patients had PEW by ISRNM criteria. Based on DMS, 73% of HD and 71% of PD patients exhibited moderate malnutrition, whilst using MIS, 88% and 90%, respectively were malnourished. DMS and MIS correlated significantly in HD (r2=0.552, pmalnutrition classification were established (score >=5) for use amongst Malaysian dialysis patients. Both DMS and MIS are valid tools to be used for nutrition screening of dialysis patients especially those undergoing peritoneal dialysis. The DMS may be a more practical and simpler tool to be utilized in the Malaysian dialysis settings as it does not require laboratory markers.

  2. Association of education level with dialysis outcome.

    Science.gov (United States)

    Khattak, Muhammad; Sandhu, Gurprataap S; Desilva, Ranil; Goldfarb-Rumyantzev, Alexander S

    2012-01-01

    The impact of education on health care outcome has been studied in the past, but its role in the dialysis population is unclear. In this report, we evaluated this association. We used the United States Renal Data System data of end-stage renal disease patients aged 18 years. Education level at the time of end-stage renal disease onset was the primary variable of interest. The outcome of the study was patient mortality. We used four categories of education level: 0 = less than 12 years of education; 1 = high school graduate; 2 = some college; 3 = college graduate. Subgroups based on age, race, sex, donor type, and diabetic status were also analyzed. After adjustments for covariates in the Cox model, using individuals with less than 12 years of education as a reference, patients with college education showed decreased mortality with hazard ratio of 0.81 (95% confidence interval 0.69–0.95), P = 0.010. In conclusion, we showed that higher education level is associated with improved survival of patients on dialysis.

  3. Modeling and control of dialysis systems

    CERN Document Server

    2013-01-01

    This book is the first text of its kind that presents both the traditional and the modern aspects of dialysis modeling and control in a clear, insightful and highly comprehensive writing style. It provides an in-depth analysis of the mathematical models and algorithms, and demonstrates their applications in real world problems of significant complexity. It explains concepts in a clear, matter-of-fact style. The material of this book will be useful to advanced undergraduate and graduate biomedical engineering students. Also, researchers and practitioners in the field of dialysis, control systems, soft computing will benefit from it. In order to make the reader aware of the applied side of the subject, the book includes:       Chapter openers with a chapter outline, chapter objectives, key terms list, and abstract.       Solved numerical examples to illustrate the application of a particular concept, and also to encourage good problem-solving skills.       More than 1000 questions to give the rea...

  4. Indications for vancomycin in dialysis patients.

    Science.gov (United States)

    Golper, T A; Schulman, G; D'Agata, E M

    2000-01-01

    Resistance to vancomycin has emerged among Staphylococcus aureus, coagulase-negative staphylococci (CNS), and enterococci, and this emergence has particular prevalence in dialysis units. It has therefore become imperative that physicians use vancomycin judiciously. General recommendations regarding the appropriate use of vancomycin have been developed. Although in theory implementation of these guidelines should not be difficult, the medical community may be unable or unwilling to make the necessary adjustments in practice. The onslaught of cost constraints and bureaucratic encumbrance has occurred simultaneously with the increase in vancomycin resistance among pathogens commonly isolated among the dialysis population. When a patient responds to empiric antibiotic therapy and susceptibility data indicate that an antibiotic other than vancomycin would be appropriate, the clinician far too often does not make the change to this alternative. Previously there was no biological imperative to change the antibiotic. That complacency has infected an entire generation of physicians, and especially nephrologists. Furthermore, there is an active movement against change, driven by concerns such as malpractice accusations and frank errors in the interpretation of medical facts.

  5. Peritoneal Dialysis Tailored to Pediatric Needs

    Directory of Open Access Journals (Sweden)

    C. P. Schmitt

    2011-01-01

    Full Text Available Consideration of specific pediatric aspects is essential to achieve adequate peritoneal dialysis (PD treatment in children. These are first of all the rapid growth, in particular during infancy and puberty, which must be accompanied by a positive calcium balance, and the age dependent changes in body composition. The high total body water content and the high ultrafiltration rates required in anuric infants for adequate nutrition predispose to overshooting convective sodium losses and severe hypotension. Tissue fragility and rapid increases in intraabdominal fat mass predispose to hernia and dialysate leaks. Peritoneal equilibration tests should repeatedly been performed to optimize individual dwell time. Intraperitoneal pressure measurements give an objective measure of intraperitoneal filling, which allow for an optimized dwell volume, that is, increased dialysis efficiency without increasing the risk of hernias, leaks, and retrofiltration. We present the concept of adapted PD, that is, the combination of short dwells with low fill volume to promote ultrafiltration and long dwells with a high fill volume to improve purification within one PD session. The use of PD solutions with low glucose degradation product content is recommended in children, but unfortunately still not feasible in many countries.

  6. Biocompatible Peritoneal Dialysis Fluids: Clinical Outcomes

    Directory of Open Access Journals (Sweden)

    Yeoungjee Cho

    2012-01-01

    Full Text Available Peritoneal dialysis (PD is a preferred home dialysis modality and has a number of added advantages including improved initial patient survival and cost effectiveness over haemodialysis. Despite these benefits, uptake of PD remains relatively low, especially in developed countries. Wider implementation of PD is compromised by higher technique failure from infections (e.g., PD peritonitis and ultrafiltration failure. These are inevitable consequences of peritoneal injury, which is thought to result primarily from continuous exposure to PD fluids that are characterised by their “unphysiologic” composition. In order to overcome these barriers, a number of more biocompatible PD fluids, with neutral pH, low glucose degradation product content, and bicarbonate buffer have been manufactured over the past two decades. Several preclinical studies have demonstrated their benefit in terms of improvement in host cell defence, peritoneal membrane integrity, and cytokine profile. This paper aims to review randomised controlled trials assessing the use of biocompatible PD fluids and their effect on clinical outcomes.

  7. [The influence of musical rhythms on the perception of subjective states of adult patients on dialysis].

    Science.gov (United States)

    Caminha, Leandro Bechert; da Silva, Maria Júlia Paes; Leão, Eliseth Ribeiro

    2009-12-01

    Being submitted to dialysis four hours a day, three times a week can mean experiencing boredom, besides discomfort. Patients often report that the time seems to take longer to go by. The purpose of this study was to explore the influence of two different musical rhythms in the states of mind and perception of adult patients undergoing dialysis, since the literature on this subject is scarce. The study was performed at a private hospital with 43 patients, who participated in two sessions of musical improvisation with a keyboard. The subjective states and perception were evaluated before and after the intervention. Over 80% of the patients felt that time went by faster after the interventions in both rhythms. However, the pace was a decisive factor in the kind of emotional experience that the patients had.

  8. Equilibrium models and variational inequalities

    CERN Document Server

    Konnov, Igor

    2007-01-01

    The concept of equilibrium plays a central role in various applied sciences, such as physics (especially, mechanics), economics, engineering, transportation, sociology, chemistry, biology and other fields. If one can formulate the equilibrium problem in the form of a mathematical model, solutions of the corresponding problem can be used for forecasting the future behavior of very complex systems and, also, for correcting the the current state of the system under control. This book presents a unifying look on different equilibrium concepts in economics, including several models from related sciences.- Presents a unifying look on different equilibrium concepts and also the present state of investigations in this field- Describes static and dynamic input-output models, Walras, Cassel-Wald, spatial price, auction market, oligopolistic equilibrium models, transportation and migration equilibrium models- Covers the basics of theory and solution methods both for the complementarity and variational inequality probl...

  9. Specific opsonic activity for staphylococci in peritoneal dialysis effluent during continuous ambulatory peritoneal dialysis

    DEFF Research Database (Denmark)

    Nielsen, H; Espersen, F; Kharazmi, A

    1992-01-01

    In a prospective study of intraperitoneal opsonins in 30 patients undergoing continuous ambulatory peritoneal dialysis (CAPD), the IgG concentration, the fibronectin concentration, the specific antistaphylococcal antibody level, and the opsonic activity against Staphylococcus epidermidis were...... measured in peritoneal dialysis effluent from the initiation of CAPD and monthly for 6 months. Significant correlation was found between the four assays, but the interindividual and intraindividual variations were considerable. No statistically significant correlation was observed between susceptibility...... of the patients to CAPD-related infectious peritonitis and any of the above-mentioned parameters of humoral defense. We conclude that at the present time it is not feasible to use these assays for the establishment of prognosis with regard to peritonitis in CAPD....

  10. Periodontal treatment reduces chronic systemic inflammation in peritoneal dialysis patients.

    Science.gov (United States)

    Siribamrungwong, Monchai; Yothasamutr, Kasemsuk; Puangpanngam, Kutchaporn

    2014-06-01

    Chronic systemic inflammation, a non traditional risk factor of cardiovascular diseases, is associated with increasing mortality in chronic kidney disease, especially peritoneal dialysis patients. Periodontitis is a potential treatable source of systemic inflammation in peritoneal dialysis patients. Clinical periodontal status was evaluated in 32 stable chronic peritoneal dialysis patients by plaque index and periodontal disease index. Hematologic, blood chemical, nutritional, and dialysis-related data as well as highly sensitive C-reactive protein were analyzed before and after periodontal treatment. At baseline, high sensitive C-reactive protein positively correlated with the clinical periodontal status (plaque index; r = 0.57, P periodontal disease index; r = 0.56, P periodontal therapy, clinical periodontal indexes were significantly lower and high sensitivity C-reactive protein significantly decreased from 2.93 to 2.21 mg/L. Moreover, blood urea nitrogen increased from 47.33 to 51.8 mg/dL, reflecting nutritional status improvement. Erythropoietin dosage requirement decreased from 8000 to 6000 units/week while hemoglobin level was stable. Periodontitis is an important source of chronic systemic inflammation in peritoneal dialysis patients. Treatment of periodontal diseases can improve systemic inflammation, nutritional status and erythropoietin responsiveness in peritoneal dialysis patients. © 2013 The Authors. Therapeutic Apheresis and Dialysis © 2013 International Society for Apheresis.

  11. Tanatophobia in the patients on dialysis

    Directory of Open Access Journals (Sweden)

    Novaković Milan

    2006-01-01

    Full Text Available Background/Aim. Thanatophobia is an exaggerated, specific, structured fear of death. It appears in childhood and continues to grow over the years, and in the old age it is accompanied with nosophobia and other mental disorders. The aim of this study was to analyze thanatophobia in dialysed patients which was in the direct connection with a basic disorder, and the influence of this disorder on functioning and the quality of life of the patients on dialysis. Methods. In the study we examined 753 patients from the chronic program of haemodialysis in a period from 1999 to 2004. The patients were classified in two groups: 348 randomized patients with Balkan Endemic Nephropathy (BEN, and the control group (N18 of patients with terminal renal insufficiency, and other diagnoses (n = 405. Since the study was a comparative, cross-sectional one, the patients were tested by the appropriate questionnaires for anxiety, depression and general mental functioning. Statistical analysis was done by the standard descriptive and analytic statistic methods. Results. Based on socio-demographics data we revealed a highly significant difference regarding the place of living between the groups BEN and N18 (χ2 = 23.970; p < 0.01, the frequency of occurrence of renal comorbidity (χ2 = 23.970; p < 0.01, the frequency of family renal comorbidity in siblings (χ2 = 23.970; p < 0.01, and the frequency of migrationes (χ2 = 4.874; p < 0.01. According to psychiatry scales, the patients from the BEN group were significantly more anxious and depressive than those from the control group. Conclusion. The signs of thanatophobia were revealed in both examined groups, but significantly more in the patients with BEN than in those with other nephrologic diseases. Thanatophobia starts before dialysis, and dialysis structures it into fear of death which is in a direct connection with the basic disorder. This intensive fear may be connected with dementia and depression, but also with

  12. Grinding kinetics and equilibrium states

    Science.gov (United States)

    Opoczky, L.; Farnady, F.

    1984-01-01

    The temporary and permanent equilibrium occurring during the initial stage of cement grinding does not indicate the end of comminution, but rather an increased energy consumption during grinding. The constant dynamic equilibrium occurs after a long grinding period indicating the end of comminution for a given particle size. Grinding equilibrium curves can be constructed to show the stages of comminution and agglomeration for certain particle sizes.

  13. Mental Equilibrium and Rational Emotions

    OpenAIRE

    Eyal Winter; Ignacio Garcia-Jurado; Jose Mendez-Naya; Luciano Mendez-Naya

    2009-01-01

    We introduce emotions into an equilibrium notion. In a mental equilibrium each player "selects" an emotional state which determines the player's preferences over the outcomes of the game. These preferences typically differ from the players' material preferences. The emotional states interact to play a Nash equilibrium and in addition each player's emotional state must be a best response (with respect to material preferences) to the emotional states of the others. We discuss the concept behind...

  14. Para-equilibrium phase diagrams

    International Nuclear Information System (INIS)

    Pelton, Arthur D.; Koukkari, Pertti; Pajarre, Risto; Eriksson, Gunnar

    2014-01-01

    Highlights: • A rapidly cooled system may attain a state of para-equilibrium. • In this state rapidly diffusing elements reach equilibrium but others are immobile. • Application of the Phase Rule to para-equilibrium phase diagrams is discussed. • A general algorithm to calculate para-equilibrium phase diagrams is described. - Abstract: If an initially homogeneous system at high temperature is rapidly cooled, a temporary para-equilibrium state may result in which rapidly diffusing elements have reached equilibrium but more slowly diffusing elements have remained essentially immobile. The best known example occurs when homogeneous austenite is quenched. A para-equilibrium phase assemblage may be calculated thermodynamically by Gibbs free energy minimization under the constraint that the ratios of the slowly diffusing elements are the same in all phases. Several examples of calculated para-equilibrium phase diagram sections are presented and the application of the Phase Rule is discussed. Although the rules governing the geometry of these diagrams may appear at first to be somewhat different from those for full equilibrium phase diagrams, it is shown that in fact they obey exactly the same rules with the following provision. Since the molar ratios of non-diffusing elements are the same in all phases at para-equilibrium, these ratios act, as far as the geometry of the diagram is concerned, like “potential” variables (such as T, pressure or chemical potentials) rather than like “normal” composition variables which need not be the same in all phases. A general algorithm to calculate para-equilibrium phase diagrams is presented. In the limit, if a para-equilibrium calculation is performed under the constraint that no elements diffuse, then the resultant phase diagram shows the single phase with the minimum Gibbs free energy at any point on the diagram; such calculations are of interest in physical vapor deposition when deposition is so rapid that phase

  15. Psychosocial predictors of nonadherence to medical management among patients on maintenance dialysis

    Directory of Open Access Journals (Sweden)

    Alosaimi FD

    2016-10-01

    Full Text Available Fahad Dakheel Alosaimi,1 Mohammed Asiri,2 Saleh Alsuwayt,2 Tariq Alotaibi,2 Mohammed Bin Mugren,2 Abdulmalik Almufarrih,2 Saad Almodameg,2 1Department of Psychiatry, King Saud University, Riyadh, Saudi Arabia; 2College of Medicine, King Saud University, Riyadh, Saudi Arabia Background: A number of reports suggest a link between depression and nonadherence to recommended management for end-stage renal disease (ESRD patients on maintenance dialysis. However, the relationship between nonadherence and other psychosocial factors have been inadequately examined. Objectives: To examine the prevalence of psychosocial factors including depression, anxiety, insecure attachment style, as well as cognitive impairment and their associations with adherence to recommended management of ESRD. Methods: A cross-sectional observational study was carried out from 2014 to 2015. Chronic dialysis patients were recruited conveniently from four major dialysis units in Riyadh, Saudi Arabia. Nonadherence was defined as decreased attendance in dialysis sessions, failure to take prescribed medications, and/or follow food/fluid restrictions and exercise recommendations. Results: A total of 234 patients (147 males and 87 females were included in this analysis, with 45 patients (19.2% considered as nonadherent (visual analog scale < 8. Approximately 17.9% of the patients had depression (Patient Health Questionnaire score ≥10, 13.2% had anxiety (Hospital Anxiety and Depression scale-anxiety >7, while 77.4% had cognitive impairment (Montreal Cognitive Assessment score <26. Nonadherence was significantly associated with depression and anxiety (p<0.001 for both but not cognitive impairment (p=0.266. The Experiences in Close Relationships – Modified 16 (ECR-M16 scale score was 27.99±10.87 for insecure anxiety and 21.71±9.06 for insecure avoidance relationship, with nonadherence significantly associated with anxiety (p=0.001 but not avoidance (p=0.400. Conclusion: Nonadherence

  16. Comparative Analysis of Serum Levels of Aluminum and Lead in Dialysis Patients, Pre and post Dialysis

    OpenAIRE

    Atieh Makhlough; Mohammad Shokrzadeh; Maryam Shaliji; Siyavash Abedi

    2014-01-01

    Background: Accumulation or deficiency of trace elements can occur in hemodialysis patients and it increases risk of cardiovascular or other organs disorders. Special ions levels such as sodium and bicarbonate in dialysis fluid are accurately regulated but the remaining elements are not regularly measured. Aluminum and lead belong to the biologic performance free heavy metals .They also has a tendency to accumulate in hemodialysis patients. This study aims to compare serum aluminum and lead l...

  17. Effects of physician payment reform on provision of home dialysis.

    Science.gov (United States)

    Erickson, Kevin F; Winkelmayer, Wolfgang C; Chertow, Glenn M; Bhattacharya, Jay

    2016-06-01

    Patients with end-stage renal disease can receive dialysis at home or in-center. In 2004, CMS reformed physician payment for in-center hemodialysis care from a capitated to a tiered fee-for-service model, augmenting physician payment for frequent in-center visits. We evaluated whether payment reform influenced dialysis modality assignment. Cohort study of patients starting dialysis in the United States in the 3 years before and the 3 years after payment reform. We conducted difference-in-difference analyses comparing patients with traditional Medicare coverage (who were affected by the policy) to others with Medicare Advantage (who were unaffected by the policy). We also examined whether the policy had a more pronounced influence on dialysis modality assignment in areas with lower costs of traveling to dialysis facilities. Patients with traditional Medicare coverage experienced a 0.7% (95% CI, 0.2%-1.1%; P = .003) reduction in the absolute probability of home dialysis use following payment reform compared with patients with Medicare Advantage. Patients living in areas with larger dialysis facilities (where payment reform made in-center hemodialysis comparatively more lucrative for physicians) experienced a 0.9% (95% CI, 0.5%-1.4%; P home dialysis use following payment reform compared with patients living in areas with smaller facilities (where payment reform made in-center hemodialysis comparatively less lucrative for physicians). The transition from a capitated to a tiered fee-for-service payment model for in-center hemodialysis care resulted in fewer patients receiving home dialysis. This area of policy failure highlights the importance of considering unintended consequences of future physician payment reform efforts.

  18. High sensitivity pyrogen testing in water and dialysis solutions.

    Science.gov (United States)

    Daneshian, Mardas; Wendel, Albrecht; Hartung, Thomas; von Aulock, Sonja

    2008-07-20

    The dialysis patient is confronted with hundreds of litres of dialysis solution per week, which pass the natural protective barriers of the body and are brought into contact with the tissue directly in the case of peritoneal dialysis or indirectly in the case of renal dialysis (hemodialysis). The components can be tested for living specimens or dead pyrogenic (fever-inducing) contaminations. The former is usually detected by cultivation and the latter by the endotoxin-specific Limulus Amoebocyte Lysate Assay (LAL). However, the LAL assay does not reflect the response of the human immune system to the wide variety of possible pyrogenic contaminations in dialysis fluids. Furthermore, the test is limited in its sensitivity to detect extremely low concentrations of pyrogens, which in their sum result in chronic pathologies in dialysis patients. The In vitro Pyrogen Test (IPT) employs human whole blood to detect the spectrum of pyrogens to which humans respond by measuring the release of the endogenous fever mediator interleukin-1beta. Spike recovery checks exclude interference. The test has been validated in an international study for pyrogen detection in injectable solutions. In this study we adapted the IPT to the testing of dialysis solutions. Preincubation of 50 ml spiked samples with albumin-coated microspheres enhanced the sensitivity of the assay to detect contaminations down to 0.1 pg/ml LPS or 0.001 EU/ml in water or saline and allowed pyrogen detection in dialysis concentrates or final working solutions. This method offers high sensitivity detection of human-relevant pyrogens in dialysis solutions and components.

  19. "End-of-Life Care? I'm not Going to Worry About That Yet." Health Literacy Gaps and End-of-Life Planning Among Elderly Dialysis Patients.

    Science.gov (United States)

    Ladin, Keren; Buttafarro, Katie; Hahn, Emily; Koch-Weser, Susan; Weiner, Daniel E

    2018-03-19

    Between 2000 and 2012, the incident dialysis population in the United States increased by nearly 60%, most sharply among adults 75 years and older. End-of-life (EOL) conversations among dialysis patients are associated with better patient-centered outcomes and lower use of aggressive interventions in the last month of life. This study examined how health literacy may affect engagement, comprehension, and satisfaction with EOL conversations among elderly dialysis patients. Qualitative/descriptive study with semi-structured interviews about health literacy, EOL conversations, and goals of care with 31 elderly dialysis patients at 2 centers in Boston. Themes were interpreted in the context of Nutbeam's health literacy framework. Despite high mortality risk in this population, only 13% of patients had discussed EOL preferences with physicians, half had discussed EOL with their social network, and 25% of participants explicitly stated that they had never considered EOL preferences. Less than 30% of participants could correctly define terminology commonly used in EOL conversations. Analyses yielded 5 themes: (1) Misunderstanding EOL terminology; (2) Nephrologists reluctant to discuss EOL; (3) Patients conforming to socially constructed roles; (4) Discordant expectations and dialysis experiences; and (5) Reconciling EOL values and future care. Patients had limited understanding of EOL terminology, lacked of opportunities for meaningful EOL discussion with providers and family, resulting in uncertainty about future care. Limited health literacy presents a substantial barrier to communication and could lead to older adults committing to an intensive pattern of care without adequate information. Clinicians should consider health literacy when discussing dialysis initiation.

  20. thermodynamics of ion exchange equilibrium for some uni

    African Journals Online (AJOL)

    a

    equilibrium studies [9-30], extending over a wide range of composition of solution and ... by dissolving their corresponding potassium salts (Analytical grade) in distilled ... calculated from which average value of K for that set of experiment was ...

  1. Amyloidosis associated with dialysis. Dialyseassoziierte Amyloidosteopathie - radiologische Aspekte

    Energy Technology Data Exchange (ETDEWEB)

    Schadmand, S.; Klose, K.J. (Mainz Univ. (Germany, F.R.). Inst. fuer Klinische Strahlenkunde); Wandel, E. (Mainz Univ. (Germany, F.R.). 1. Medizinische Klinik und Poliklinik)

    1991-06-01

    Amongst the complications of dialysis, amyloid osteopathy is getting increasingly significant. It is due to deposition of {beta}2-microglobulin. To determine the incidence and time of development of this complication, the skeletal radiographs of 185 patients undergoing dialysis, some for up to ten years, were analysed retrospectively. In about 10% of patients, the presence of {beta}2-microglobulin osteopathy may be expected. The radiological features, sites of predilection and differential diagnosis of amyloid osteopathy and of other skeletal changes due to dialysis are discussed. (orig.).

  2. Glucose absorption in acute peritoneal dialysis.

    Science.gov (United States)

    Podel, J; Hodelin-Wetzel, R; Saha, D C; Burns, G

    2000-04-01

    During acute peritoneal dialysis (APD), it is known that glucose found in the dialysate solution contributes to the provision of significant calories. It has been well documented in continuous ambulatory peritoneal dialysis (CAPD) that glucose absorption occurs. In APD, however, it remains unclear how much glucose absorption actually does occur. Therefore, the purpose of this study was to determine whether it is appropriate to use the formula used to calculate glucose absorption in CAPD (Grodstein et al) among patients undergoing APD. Actual measurements of glucose absorption (Method I) were calculated in 9 patients undergoing APD treatment for >24 hours who were admitted to the intensive care unit. Glucose absorption using the Grodstein et al formula (Method II) was also determined and compared with the results of actual measurements. The data was then further analyzed based on the factors that influence glucose absorption, specifically dwell time and concentration. The mean total amount of glucose absorbed was 43% +/- 15%. However, when dwell time and concentration were further examined, significant differences were noted. Method I showed a cumulative increase over time. Method II showed that absorption was fixed. This suggests that with the variation in dwell time commonly seen in the acute care setting, the use of Method II may not be accurate. In each of the 2 methods, a significant difference in glucose absorption was noted when comparing the use of 1.5% and 4.25% dialysate concentrations. The established formula designed for CAPD should not be used for calculating glucose absorption in patients receiving APD because variation in dwell time and concentration should be taken into account. Because of the time constraints and staffing required to calculate each exchange individually, combined with the results of the study, we recommend the use of the percentage estimate of 40% to 50%.

  3. Bladder perforation in a peritoneal dialysis patient

    Directory of Open Access Journals (Sweden)

    M Ounissi

    2012-01-01

    Full Text Available The dysfunction of the catheter in peritoneal dialysis (PD is a frequent compli-cation. However, perforation of organs are rare, particularly that of the urinary bladder. This re-quires an early diagnosis and prompt treatment of patients. We report here the case of a 38-year-old woman having end-stage renal disease due to autosomal-dominant polycystic kidney disease treated by PD since November 2000. Three years later, she was treated for Staphylococcal peritonitis. Four months later, she presented with a severe urge to urinate at the time of the fluid exchanges. The biochemical analysis of the fluid from the bladder showed that it was dialysis fluid. Injection of contrast through the catheter demonstrated the presence of a fistula between the bladder and the peritoneal cavity. She underwent cystoscopic closure of the fistulous tract and the PD catheter was removed. Subsequently, the patient was treated by hemodialysis. One month later, a second catheter was implanted surgically after confirming the closure of the fistula. Ten days later, she presented with pain at the catheter site and along the tunnel, which was found to be swollen along its track. The injection of contrast produced swelling of the subcutaneous tunnel but without extravasation of the dye. PD was withdrawn and the patient was put back on hemodialysis. Bladder fistula is a rare complication in PD and diagnosis should be suspected when patient complains of an urge to pass urine during the exchanges, which can be confirmed by contrast study showing presence of dye in the bladder. PD may be possible after the closure of the fistula, but recurrence may occur.

  4. Hypothyroidism and Mortality among Dialysis Patients

    Science.gov (United States)

    Rhee, Connie M.; Alexander, Erik K.; Bhan, Ishir

    2013-01-01

    Summary Background and objectives Hypothyroidism is highly prevalent among ESRD patients, but its clinical significance and the benefits of thyroid hormone replacement in this context remain unclear. Design, setting, participants, & measurements This study examined the association between hypothyroidism and all-cause mortality among 2715 adult dialysis patients with baseline thyrotropin levels measured between April of 2005 and April of 2011. Mortality was ascertained from Social Security Death Master Index and local registration systems. The association between hypothyroidism (thyrotropin greater than assay upper limit normal) and mortality was estimated using Cox proportional hazards models. To reduce the risk of observing reverse-causal associations, models included a 30-day lag between thyrotropin measurement and at-risk time. Results Among 350 (12.9%) hypothyroid and 2365 (87.1%) euthyroid (assay within referent range) patients, 917 deaths were observed during 5352 patient-years of at-risk time. Hypothyroidism was associated with higher mortality. Compared with thyrotropin in the low-normal range (0.4–2.9 mIU/L), subclinical hypothyroidism (thyrotropin >upper limit normal and ≤10.0 mIU/L) was associated with higher mortality; high-normal thyrotropin (≥3.0 mIU/L and ≤upper limit normal) and overt hypothyroidism (thyrotropin >10.0 mIU/L) were associated with numerically greater risk, but estimates were not statistically significant. Compared with spontaneously euthyroid controls, patients who were euthyroid while on exogenous thyroid replacement were not at higher mortality risk, whereas patients who were hypothyroid were at higher mortality risk. Sensitivity analyses indicated that effects on cardiovascular risk factors may mediate the observed association between hypothyroidism and death. Conclusions These data suggest that hypothyroidism is associated with higher mortality in dialysis patients, which may be ameliorated by thyroid hormone replacement

  5. Thermodynamic chemical energy transfer mechanisms of non-equilibrium, quasi-equilibrium, and equilibrium chemical reactions

    International Nuclear Information System (INIS)

    Roh, Heui-Seol

    2015-01-01

    Chemical energy transfer mechanisms at finite temperature are explored by a chemical energy transfer theory which is capable of investigating various chemical mechanisms of non-equilibrium, quasi-equilibrium, and equilibrium. Gibbs energy fluxes are obtained as a function of chemical potential, time, and displacement. Diffusion, convection, internal convection, and internal equilibrium chemical energy fluxes are demonstrated. The theory reveals that there are chemical energy flux gaps and broken discrete symmetries at the activation chemical potential, time, and displacement. The statistical, thermodynamic theory is the unification of diffusion and internal convection chemical reactions which reduces to the non-equilibrium generalization beyond the quasi-equilibrium theories of migration and diffusion processes. The relationship between kinetic theories of chemical and electrochemical reactions is also explored. The theory is applied to explore non-equilibrium chemical reactions as an illustration. Three variable separation constants indicate particle number constants and play key roles in describing the distinct chemical reaction mechanisms. The kinetics of chemical energy transfer accounts for the four control mechanisms of chemical reactions such as activation, concentration, transition, and film chemical reactions. - Highlights: • Chemical energy transfer theory is proposed for non-, quasi-, and equilibrium. • Gibbs energy fluxes are expressed by chemical potential, time, and displacement. • Relationship between chemical and electrochemical reactions is discussed. • Theory is applied to explore nonequilibrium energy transfer in chemical reactions. • Kinetics of non-equilibrium chemical reactions shows the four control mechanisms

  6. Fundamental functions in equilibrium thermodynamics

    NARCIS (Netherlands)

    Horst, H.J. ter

    In the standard presentations of the principles of Gibbsian equilibrium thermodynamics one can find several gaps in the logic. For a subject that is as widely used as equilibrium thermodynamics, it is of interest to clear up such questions of mathematical rigor. In this paper it is shown that using

  7. Equivalent Fall Risk in Elderly Patients on Hemodialysis and Peritoneal Dialysis.

    Science.gov (United States)

    Farragher, Janine; Rajan, Tasleem; Chiu, Ernest; Ulutas, Ozkan; Tomlinson, George; Cook, Wendy L; Jassal, Sarbjit V

    2016-01-01

    ♦ Accidental falls are common in the hemodialysis (HD) population. The high fall rate has been attributed to a combination of aging, kidney disease-related morbidity, and HD treatment-related hazards. We hypothesized that patients maintained on peritoneal dialysis (PD) would have fewer falls than those on chronic HD. The objective of this study was to compare the falls risk between cohorts of elderly patients maintained on HD and PD, using prospective data from a large academic dialysis facility. ♦ Patients aged 65 years or over on chronic in-hospital HD and PD at the University Health Network were recruited. Patients were followed biweekly, and falls occurring within the first year recorded. Fall risk between the 2 groups was compared using both crude and adjusted Poisson lognormal random effects modeling. ♦ Out of 258 potential patients, 236 were recruited, assessed at baseline, and followed biweekly for falls. Of 74 PD patients, 40 (54%) experienced 86 falls while 76 out of 162 (47%) HD patients experienced a total of 305 falls (crude fall rate 1.25 vs 1.60 respectively, odds ratio [OR] falls in PD patients 0.78, 95% confidence interval [CI] 0.61 - 0.92, p = 0.04). After adjustment for differences in comorbidity, number of medications, and other demographic differences, PD patients were no less likely to experience accidental falls than HD patients (OR 1.63, 95% CI 0.88 - 3.04, p = 0.1). ♦ We conclude that accidental falls are equally common in the PD population and the HD population. These data argue against post-HD hypotension as the sole contributor to the high fall risk in the dialysis population. Copyright © 2016 International Society for Peritoneal Dialysis.

  8. Dialysis facility staff perceptions of racial, gender, and age disparities in access to renal transplantation.

    Science.gov (United States)

    Lipford, Kristie J; McPherson, Laura; Hamoda, Reem; Browne, Teri; Gander, Jennifer C; Pastan, Stephen O; Patzer, Rachel E

    2018-01-10

    Racial/ethnic, gender, and age disparities in access to renal transplantation among end-stage renal disease (ESRD) patients have been well documented, but few studies have explored health care staff attitudes towards these inequalities. Staff perceptions can influence patient care and outcomes, and identifying staff perceptions on disparities could aid in the development of potential interventions to address these health inequities. The objective of this study was to investigate dialysis staff (n = 509), primarily social workers and nurse managers, perceptions of renal transplant disparities in the Southeastern United States. This is a mixed methods study that uses both deductive and inductive qualitative analysis of a dialysis staff survey conducted in 2012 using three open-ended questions that asked staff to discuss their perceptions of factors that may contribute to transplant disparities among African American, female, and elderly patients. Study results suggested that the majority of staff (n = 255, 28%) perceived patients' low socioeconomic status as the primary theme related to why renal transplant disparities exist between African Americans and non-Hispanic whites. Staff cited patient perception of old age as a primary contributor (n = 188, 23%) to the disparity between young and elderly patients. The dialysis staff responses on gender transplant disparities suggested that staff were unaware of differences due to limited experience and observation (n = 76, 14.7%) of gender disparities. These findings suggest that dialysis facilities should educate staff on existing renal transplantation disparities, particularly gender disparities, and collaboratively work with transplant facilities to develop strategies to actively address modifiable patient barriers for transplant.

  9. Determinants of Peritoneal Dialysis Technique Failure in Incident US Patients

    OpenAIRE

    Shen, Jenny I.; Mitani, Aya A.; Saxena, Anjali B.; Goldstein, Benjamin A.; Winkelmayer, Wolfgang C.

    2013-01-01

    ♦ Objectives: Switching from peritoneal dialysis (PD) to hemodialysis (HD) is undesirable, because of complications from temporary vascular access, disruption of daily routine, and higher costs. Little is known about the role that social factors play in technique failure.

  10. Kidney Dialysis: When Is It Time to Stop?

    Science.gov (United States)

    ... is it time to stop? My 82-year-old husband has been on kidney dialysis for a ... of Privacy Practices Notice of Nondiscrimination Manage Cookies Advertising Mayo Clinic is a not-for-profit organization ...

  11. Analysis of Why the Renal Dialysis Unit is Losing Money

    National Research Council Canada - National Science Library

    Moore, Leslie

    1997-01-01

    .... Despite efforts to remain competitive by procuring "state of the art" equipment intended to decrease treatment times and result in cost savings, the renal dialysis product line was losing money...

  12. Diabetic patients treated with dialysis: complications and quality of life

    DEFF Research Database (Denmark)

    Sørensen, V R; Mathiesen, E R; Watt, T

    2007-01-01

    AIMS/HYPOTHESIS: The aim of this study was to describe the prevalence of complications, health-related quality of life (HRQOL) and the influence of beliefs about control over health in diabetic dialysis patients. METHODS: Of 53 eligible diabetic patients on chronic dialysis during January 2004...... in our clinic, 38 (76%) completed a kidney-specific (Kidney Disease Quality of Life) and a generic (SF-36) questionnaire and were characterised in terms of cardiovascular diseases and diabetic complications. Matched groups of non-diabetic dialysis patients (n = 40) and diabetic patients with a long...... population (47 +/- 19). The diabetic dialysis patients had similar levels of kidney-specific quality of life and mental health compared with the control groups. Reduced physical health was predicted by the presence of end-stage renal disease, diabetes and short time spent in education. Among the diabetic...

  13. Pharmacokinetics of amikacin during hemodialysis and peritoneal dialysis

    DEFF Research Database (Denmark)

    Regeur, L; Colding, H; Jensen, H

    1977-01-01

    The pharmacokinetics of amikacin were examined in six bilaterally nephrectomized patients undergoing hemodialysis and in four patients with a minimal residual renal function undergoing peritoneal dialysis. The mean elimination half-life before the dialysis was 86.5 h in the anephric patients and 44...... renal function. During hemodialysis the half-life decreased to less than 10% (5.6 h) of the pretreatment value. The effectiveness of peritoneal dialysis was less as the half-life decreased to only about 30% (17.9 h) of the pretreatment value. During the dialyses a significant correlation between...... the half-life of amikacin and the decrease in blood urea and serum creatinine was demonstrated. The pharmacokinetic data were used to make dosage regimen recommendations for the treatment of patients undergoing intermittent hemodialysis or peritoneal dialysis....

  14. Increasing fill volume reduces cardiac performance in peritoneal dialysis

    DEFF Research Database (Denmark)

    Ivarsen, Per; Povlsen, Johan V; Jensen, Jens Dam

    2007-01-01

    BACKGROUND: It is generally accepted that peritoneal dialysis (PD) affects systemic haemodynamics less than haemodialysis, but little is known about changes in haemodynamics during PD. It is unknown if increasing PD volume causes changes in cardiovascular haemodynamics possibly increasing...

  15. Peritonitis in peritoneal dialysis patients after renal transplantation

    NARCIS (Netherlands)

    Bakir, N; Surachno, S; Sluiter, WJ; Struijk, DG

    1998-01-01

    Background. The occurrence of peritonitis in peritoneal dialysis patients after renal transplantation during immunosuppression might increase morbidity and mortality. Hence the timing of catheter removal is still controversial. The associated risk factors of this complication have not been analyzed.

  16. Peritonitis in peritoneal dialysis patients after renal transplantation

    NARCIS (Netherlands)

    Bakir, N.; Surachno, S.; Sluiter, W. J.; Struijk, D. G.

    1998-01-01

    The occurrence of peritonitis in peritoneal dialysis patients after renal transplantation during immunosuppression might increase morbidity and mortality. Hence the timing of catheter removal is still controversial. The associated risk factors of this complication have not been analyzed. We

  17. A Multiperiod Equilibrium Pricing Model

    Directory of Open Access Journals (Sweden)

    Minsuk Kwak

    2014-01-01

    Full Text Available We propose an equilibrium pricing model in a dynamic multiperiod stochastic framework with uncertain income. There are one tradable risky asset (stock/commodity, one nontradable underlying (temperature, and also a contingent claim (weather derivative written on the tradable risky asset and the nontradable underlying in the market. The price of the contingent claim is priced in equilibrium by optimal strategies of representative agent and market clearing condition. The risk preferences are of exponential type with a stochastic coefficient of risk aversion. Both subgame perfect strategy and naive strategy are considered and the corresponding equilibrium prices are derived. From the numerical result we examine how the equilibrium prices vary in response to changes in model parameters and highlight the importance of our equilibrium pricing principle.

  18. Non-equilibrium phase transitions

    CERN Document Server

    Henkel, Malte; Lübeck, Sven

    2009-01-01

    This book describes two main classes of non-equilibrium phase-transitions: (a) static and dynamics of transitions into an absorbing state, and (b) dynamical scaling in far-from-equilibrium relaxation behaviour and ageing. The first volume begins with an introductory chapter which recalls the main concepts of phase-transitions, set for the convenience of the reader in an equilibrium context. The extension to non-equilibrium systems is made by using directed percolation as the main paradigm of absorbing phase transitions and in view of the richness of the known results an entire chapter is devoted to it, including a discussion of recent experimental results. Scaling theories and a large set of both numerical and analytical methods for the study of non-equilibrium phase transitions are thoroughly discussed. The techniques used for directed percolation are then extended to other universality classes and many important results on model parameters are provided for easy reference.

  19. Time to Improve Informed Consent for Dialysis: An International Perspective.

    Science.gov (United States)

    Brennan, Frank; Stewart, Cameron; Burgess, Hannah; Davison, Sara N; Moss, Alvin H; Murtagh, Fliss E M; Germain, Michael; Tranter, Shelley; Brown, Mark

    2017-06-07

    The literature reveals that current nephrology practice in obtaining informed consent for dialysis falls short of ethical and legal requirements. Meeting these requirements represents a significant challenge, especially because the benefits and risks of dialysis have shifted significantly with the growing number of older, comorbid patients. The importance of informed consent for dialysis is heightened by several concerns, including: ( 1 ) the proportion of predialysis patients and patients on dialysis who lack capacity in decision making and ( 2 ) whether older, comorbid, and frail patients understand their poor prognosis and the full implications to their independence and functional status of being on dialysis. This article outlines the ethical and legal requirements for a valid informed consent to dialysis: ( 1 ) the patient was competent, ( 2 ) the consent was made voluntarily, and ( 3 ) the patient was given sufficient information in an understandable manner to make the decision. It then considers the application of these requirements to practice across different countries. In the process of informed consent, the law requires a discussion by the physician of the material risks associated with dialysis and alternative options. We argue that, legally and ethically, this discussion should include both the anticipated trajectory of the illness and the effect on the life of the patient with particular regard to the outcomes most important to the individual. In addition, a discussion should occur about the option of a conservative, nondialysis pathway. These requirements ensure that the ethical principle of respect for patient autonomy is honored in the context of dialysis. Nephrologists need to be open to, comfortable with, and skillful in communicating this information. From these clear, open, ethically, and legally valid consent discussions, a significant dividend will hopefully flow for patients, families, and nephrologists alike. Copyright © 2017 by the

  20. Graves′ disease in a dialysis dependent chronic renal failure patient

    Directory of Open Access Journals (Sweden)

    C G Nair

    2014-01-01

    Full Text Available Thyroid hormone level may be altered in chronic renal failure patients. Low levels of thyroxine protect the body from excess protein loss by minimizing catabolism. Hyperthyroidism is rarely encountered in end-stage dialysis dependent patients. Less than 10 well-documented cases of Graves′ disease (GD are reported in literature so far. We report a case of GD in a patient on dialysis.

  1. Daily dialysis reduces pulse wave velocity in chronic hemodialysis patients.

    Science.gov (United States)

    Di Micco, Lucia; Torraca, Serena; Sirico, Maria Luisa; Tartaglia, Domenico; Di Iorio, Biagio

    2012-05-01

    Pulse wave velocity (PWV) is a predictor of morbidity and mortality in patients with end-stage renal disease (ESRD). Dialysis patients show cyclic changes in PWV related to their hydration status and blood pressure. Our aim is to assess the impact of daily dialysis on PWV. We performed a randomized crossover study of 60 patients who underwent standard hemodialysis (HD) three times per week for at least 6 months. Patients were classified into three groups according to their PWV values before (pre-) and after (post-) HD, with a cutoff value of 12 m s(-1), as follows: the low-low (LL) group had normal pre-HD and post-HD PWV; the high-low (HL) group had high pre-HD PWV and normal post-HD PWV; and the high-high (HH) group had high pre- and post-HD PWV. All patients continued standard HD for 2 weeks. A total of 10 patients from each group were randomly assigned to continue standard HD for 1 week and then underwent daily dialysis for 1 week. The remaining 10 patients underwent daily dialysis for 1 week and then underwent standard HD for 1 week. PWV values were measured before and 1 h after each dialysis session. With daily dialysis treatment, 2 of 20 patients (10%) moved from the PWV-HH group to the PWV-HL group, whereas 18 of 20 patients (90%) moved from the PWV-HL group to the PWV-LL group (P = 0.030). Daily dialysis reduces PWV in the ESRD patients. As PWV is a strong predictor of mortality in ESRD and has cyclic variations in patients who are on standard HD, we believe that daily dialysis may be used in patients with high PWV levels to reduce their mortality risk.

  2. Mathematical modeling of fluid and solute transport in peritoneal dialysis

    OpenAIRE

    Waniewski, Jacek

    2001-01-01

    Optimization of peritoneal dialysis schedule and dialysis fluid composition needs, among others, methods for quantitative assessment of fluid and solute transport. Furthermore, an integrative quantitative description of physiological processes within the tissue, which contribute to the net transfer of fluid and solutes, is necessary for interpretation of the data and for predictions of the outcome of possible intervention into the peritoneal transport system. The current pro...

  3. [Customization of hemodialysis therapy: dialysis is not a washing machine].

    Science.gov (United States)

    Santoro, Antonio

    2018-02-01

    In recent years, the population of chronic dialysis has grown in number but also in age and frequency of co-morbidies such as cardiac diseases, vascular pathologies, diabetes, etc. The majority of patients on chronic hemodialysis are over 70 years and, given the high number of comorbidities, they often exhibit poor tolerance to dialysis treatments. A non-tolerated dialytic treatment can have side-effects that would require an intensification of the dialysis sessions and many hospitalizations. Consequently, the problematic dialysis treatments, as well as harmful for the patient, become economically more detrimental than other treatments apparently more expensive but more tolerated ones In the current days we have, thanks to the huge developments in dialysis technology, powerful weapons to ensure effective and scarcely symptomatic dialysis treatments to the majority of the HD patients. New, highly biocompatible membranes with defined and modular cut-off and / or absorption capacity may allow us to provide adequate purification. Moreover the monitoring and biofeedback systems such as blood volume tracking, body temperature monitoring (BTM) and blood pressure (BPM) can be very useful in reducing the risk of intra-dialytic hypotension and symptoms. Therefore, the dialytic therapy, as well as all the pharmacological therapies for the chronic patient, must consider the specificity of the patient, basing on his metabolic problems, cardiovascular tolerance, residual renal function and on his dietary and general compliance. The central aim of the nephrologist is to formulate the better prescription for the individual patient, considering the dialysis modalities, the membrane type, the dry weight (ideal post-dialysis body weight), the frequency and the duration of the weekly sessions and the technological tools that can optimize the treatment. Copyright by Società Italiana di Nefrologia SIN, Rome, Italy.

  4. Transperitoneal transport of sodium during hypertonic peritoneal dialysis

    DEFF Research Database (Denmark)

    Graff, J; Fugleberg, S; Brahm, J

    1996-01-01

    The mechanisms of transperitoneal sodium transport during hypertonic peritoneal dialysis were evaluated by kinetic modelling. A total of six nested mathematical models were designed to elucidate the presence or absence of diffusive, non-lymphatic convective and lymphatic convective solute transport....... Experimental results were obtained from 26 non-diabetic patients undergoing peritoneal dialysis. The model validation procedure demonstrated that only diffusive and non-lymphatic convective transport mechanisms were identifiable in the transperitoneal transport of sodium. Non-lymphatic convective sodium...

  5. Pregnancy in chronic dialysis, late diagnosis, and other problems

    Science.gov (United States)

    Ramadani, S.; Nasution, A. T.; Nasution, S.; Lubis, H. R.

    2018-03-01

    The incidence of pregnancy in patients with chronic kidney disease (CKD) undergoing hemodialysis is rare. Forpregnant patients with CKD undergoing regular hemodialysis, the effects of renal disease on the fetus should be noted and require specific strategies. A 30-year-old woman had no menstruation for 4 months. Abdominal ultrasound showed single fetus within 16 weeks of pregnancy. She had previously been in regular hemodialysis twice a week since 2015, then the frequency of hemodialysis was increased to thrice a week for 4 hours/dialysis. During pregnancy, she was given erythropoiesis stimulating agent, controlled protein nutrition (0.6-1.5g/kg/day) and routine pregnancy controls to an obstetrician. After 31-32 weeks gestation, thebaby was born alive with low birth weight (1800g). Maintaining pregnancy in women with regular hemodialysis is still challenging and difficult. Prolonged/intensive dialysis during pregnancy results in longer gestational periods, higher fetal weights, and a higher likelihood of survival. Based on a dialysis guideline for pregnancy in CKD, hemodialysis is performed at least 20 hours/week to maintain pre-dialysis of BUN≤50mg/dl hemoglobin should be at least 10-11g/dL. We reported a case of pregnancy in dialysis CKD patient undergoing hemodialysis thricea week (4 hours/dialysis). The baby was born alive with low birth weight (1800 g).

  6. Continuous ambulatory peritoneal dialysis: perspectives on patient selection in low- to middle-income countries

    Directory of Open Access Journals (Sweden)

    Wearne N

    2017-01-01

    Full Text Available Nicola Wearne,1 Kajiru Kilonzo,2 Emmanuel Effa,3 Bianca Davidson,1 Peter Nourse,4 Udeme Ekrikpo,1,5 Ikechi G Okpechi1 1Division of Nephrology and Hypertension, University of Cape Town, Cape Town, South Africa; 2Department of Medicine, Kilimanjaro Christian Medical College, Moshi, Tanzania; 3Department of Medicine, University of Calabar, Calabar, Nigeria; 4Division of Paediatric Nephrology, Red Cross War Memorial Children’s Hospital, Cape Town, South Africa; 5Department of Internal Medicine, University of Uyo, Uyo, Nigeria Abstract: Chronic kidney disease is a major public health problem that continues to show an unrelenting global increase in prevalence. The prevalence of chronic kidney disease has been predicted to grow the fastest in low- to middle-income countries (LMICs. There is evidence that people living in LMICs have the highest need for renal replacement therapy (RRT despite the lowest access to various modalities of treatment. As continuous ambulatory peritoneal dialysis (CAPD does not require advanced technologies, much infrastructure, or need for dialysis staff support, it should be an ideal form of RRT in LMICs, particularly for those living in remote areas. However, CAPD is scarcely available in many LMICs, and even where available, there are several hurdles to be confronted regarding patient selection for this modality. High cost of CAPD due to unavailability of fluids, low patient education and motivation, low remuneration for nephrologists, lack of expertise/experience for catheter insertion and management of complications, presence of associated comorbid diseases, and various socio-demographic factors contribute significantly toward reduced patient selection for CAPD. Cost of CAPD fluids seems to be a major constraint given that many countries do not have the capacity to manufacture fluids but instead rely heavily on fluids imported from developed countries. There is need to invest in fluid manufacturing (either nationally or

  7. Non-equilibrium supramolecular polymerization.

    Science.gov (United States)

    Sorrenti, Alessandro; Leira-Iglesias, Jorge; Markvoort, Albert J; de Greef, Tom F A; Hermans, Thomas M

    2017-09-18

    Supramolecular polymerization has been traditionally focused on the thermodynamic equilibrium state, where one-dimensional assemblies reside at the global minimum of the Gibbs free energy. The pathway and rate to reach the equilibrium state are irrelevant, and the resulting assemblies remain unchanged over time. In the past decade, the focus has shifted to kinetically trapped (non-dissipative non-equilibrium) structures that heavily depend on the method of preparation (i.e., pathway complexity), and where the assembly rates are of key importance. Kinetic models have greatly improved our understanding of competing pathways, and shown how to steer supramolecular polymerization in the desired direction (i.e., pathway selection). The most recent innovation in the field relies on energy or mass input that is dissipated to keep the system away from the thermodynamic equilibrium (or from other non-dissipative states). This tutorial review aims to provide the reader with a set of tools to identify different types of self-assembled states that have been explored so far. In particular, we aim to clarify the often unclear use of the term "non-equilibrium self-assembly" by subdividing systems into dissipative, and non-dissipative non-equilibrium states. Examples are given for each of the states, with a focus on non-dissipative non-equilibrium states found in one-dimensional supramolecular polymerization.

  8. Spontaneity and Equilibrium: Why "?G Equilibrium" Are Incorrect

    Science.gov (United States)

    Raff, Lionel M.

    2014-01-01

    The fundamental criteria for chemical reactions to be spontaneous in a given direction are generally incorrectly stated as ?G equilibrium are also misstated as being ?G = 0 or ?A = 0. Following a brief review of the…

  9. Prevalence of Cognitive Impairment Among Peritoneal Dialysis Patients, Impact on Peritonitis and Role of Assisted Dialysis.

    Science.gov (United States)

    Shea, Yat Fung; Lam, Man Fai; Lee, Mi Suen Connie; Mok, Ming Yee Maggie; Lui, Sing-Leung; Yip, Terence P S; Lo, Wai Kei; Chu, Leung Wing; Chan, Tak-Mao

    2016-01-01

    ♦ Chronic renal failure and aging are suggested as risk factors for cognitive impairment (CI). We studied the prevalence of CI among peritoneal dialysis (PD) patients using Montreal Cognitive Assessment (MoCA), its impact on PD-related peritonitis in the first year, and the potential role of assisted PD. ♦ One hundred fourteen patients were newly started on PD between February 2011 and July 2013. Montreal Cognitive Assessment was performed in the absence of acute illness. Data on patient characteristics including demographics, comorbidities, blood parameters, dialysis adequacy, presence of helpers, medications, and the number PD-related infections were collected. ♦ The age of studied patients was 59±15.0 years, and 47% were female. The prevalence of CI was 28.9%. Patients older than 65 years old (odds ratio [OR] 4.88, confidence interval [CI] 1.79 - 13.28 p = 0.002) and with an education of primary level or below (OR 4.08, CI 1.30 - 12.81, p = 0.016) were independent risk factors for CI in multivariate analysis. Patients with PD-related peritonitis were significantly older (p peritonitis among self-care PD patients (OR 2.20, CI 0.65 - 7.44, p = 0.20). When we compared patients with MoCA-defined CI receiving self-care and assisted PD, there were no statistically significant differences between the 2 groups in terms of age, MoCA scores, or comorbidities. There were also no statistically significant differences in 1-year outcome of PD-related peritonitis rates or exit-site infections. ♦ Cognitive impairment is common among local PD patients. Even with CI, peritonitis rate in self-care PD with adequate training is similar to CI patients on assisted PD. Copyright © 2016 International Society for Peritoneal Dialysis.

  10. Helical axis stellarator equilibrium model

    International Nuclear Information System (INIS)

    Koniges, A.E.; Johnson, J.L.

    1985-02-01

    An asymptotic model is developed to study MHD equilibria in toroidal systems with a helical magnetic axis. Using a characteristic coordinate system based on the vacuum field lines, the equilibrium problem is reduced to a two-dimensional generalized partial differential equation of the Grad-Shafranov type. A stellarator-expansion free-boundary equilibrium code is modified to solve the helical-axis equations. The expansion model is used to predict the equilibrium properties of Asperators NP-3 and NP-4. Numerically determined flux surfaces, magnetic well, transform, and shear are presented. The equilibria show a toroidal Shafranov shift

  11. Peritoneal Fluid Transport rather than Peritoneal Solute Transport Associates with Dialysis Vintage and Age of Peritoneal Dialysis Patients

    Directory of Open Access Journals (Sweden)

    Jacek Waniewski

    2016-01-01

    Full Text Available During peritoneal dialysis (PD, the peritoneal membrane undergoes ageing processes that affect its function. Here we analyzed associations of patient age and dialysis vintage with parameters of peritoneal transport of fluid and solutes, directly measured and estimated based on the pore model, for individual patients. Thirty-three patients (15 females; age 60 (21–87 years; median time on PD 19 (3–100 months underwent sequential peritoneal equilibration test. Dialysis vintage and patient age did not correlate. Estimation of parameters of the two-pore model of peritoneal transport was performed. The estimated fluid transport parameters, including hydraulic permeability (LpS, fraction of ultrasmall pores (αu, osmotic conductance for glucose (OCG, and peritoneal absorption, were generally independent of solute transport parameters (diffusive mass transport parameters. Fluid transport parameters correlated whereas transport parameters for small solutes and proteins did not correlate with dialysis vintage and patient age. Although LpS and OCG were lower for older patients and those with long dialysis vintage, αu was higher. Thus, fluid transport parameters—rather than solute transport parameters—are linked to dialysis vintage and patient age and should therefore be included when monitoring processes linked to ageing of the peritoneal membrane.

  12. Peritoneal Fluid Transport rather than Peritoneal Solute Transport Associates with Dialysis Vintage and Age of Peritoneal Dialysis Patients

    Science.gov (United States)

    Waniewski, Jacek; Antosiewicz, Stefan; Baczynski, Daniel; Poleszczuk, Jan; Pietribiasi, Mauro; Lindholm, Bengt; Wankowicz, Zofia

    2016-01-01

    During peritoneal dialysis (PD), the peritoneal membrane undergoes ageing processes that affect its function. Here we analyzed associations of patient age and dialysis vintage with parameters of peritoneal transport of fluid and solutes, directly measured and estimated based on the pore model, for individual patients. Thirty-three patients (15 females; age 60 (21–87) years; median time on PD 19 (3–100) months) underwent sequential peritoneal equilibration test. Dialysis vintage and patient age did not correlate. Estimation of parameters of the two-pore model of peritoneal transport was performed. The estimated fluid transport parameters, including hydraulic permeability (LpS), fraction of ultrasmall pores (α u), osmotic conductance for glucose (OCG), and peritoneal absorption, were generally independent of solute transport parameters (diffusive mass transport parameters). Fluid transport parameters correlated whereas transport parameters for small solutes and proteins did not correlate with dialysis vintage and patient age. Although LpS and OCG were lower for older patients and those with long dialysis vintage, αu was higher. Thus, fluid transport parameters—rather than solute transport parameters—are linked to dialysis vintage and patient age and should therefore be included when monitoring processes linked to ageing of the peritoneal membrane. PMID:26989432

  13. Non-equilibrium spectroscopy of high-Tc superconductors

    International Nuclear Information System (INIS)

    Krasnov, V M

    2009-01-01

    In superconductors, recombination of two non-equilibrium quasiparticles into a Cooper pair results in emission of excitation that mediates superconductivity. This is the basis of the proposed new type of 'non-equilibrium' spectroscopy of high T c superconductors, which may open a possibility for direct and unambiguous determination of the coupling mechanism of high T c superconductivity. In case of low T c superconductors, the feasibility of such the non-equilibrium spectroscopy was demonstrated in classical phonon generation-detection experiments almost four decades ago. Recently it was demonstrated that a similar technique can be used for high T c superconductors, using natural intrinsic Josephson junctions both for injection of non-equilibrium quasiparticles and for detection of the non-equilibrium radiation. Here I analyze theoretically non-equilibrium phenomena in intrinsic Josephson junctions. It is shown that extreme non-equilibrium state can be achieved at bias equal to integer number of the gap voltage, which can lead to laser-like emission from the stack. I argue that identification of the boson type, constituting this non-equilibrium radiation would unambiguously reveal the coupling mechanism of high Tc superconductors.

  14. Early Dialysis and Adverse Outcomes After Hurricane Sandy.

    Science.gov (United States)

    Lurie, Nicole; Finne, Kristen; Worrall, Chris; Jauregui, Maria; Thaweethai, Tanayott; Margolis, Gregg; Kelman, Jeffrey

    2015-09-01

    Hemodialysis patients have historically experienced diminished access to care and increased adverse outcomes after natural disasters. Although "early dialysis" in advance of a storm is promoted as a best practice, evidence for its effectiveness as a protective measure is lacking. Building on prior work, we examined the relationship between the receipt of dialysis ahead of schedule before the storm (also known as early dialysis) and adverse outcomes of patients with end-stage renal disease in the areas most affected by Hurricane Sandy. Retrospective cohort analysis, using claims data from the Centers for Medicare & Medicaid Services Datalink Project. Patients receiving long-term hemodialysis in New York City and the state of New Jersey, the areas most affected by Hurricane Sandy. Receipt of early dialysis compared to their usual treatment pattern in the week prior to the storm. Emergency department (ED) visits, hospitalizations, and 30-day mortality following the storm. Of 13,836 study patients, 8,256 (60%) received early dialysis. In unadjusted logistic regression models, patients who received early dialysis were found to have lower odds of ED visits (OR, 0.75; 95% CI, 0.63-0.89; P=0.001) and hospitalizations (OR, 0.77; 95% CI, 0.65-0.92; P=0.004) in the week of the storm and similar odds of 30-day mortality (OR, 0.80; 95% CI, 0.58-1.09; P=0.2). In adjusted multivariable logistic regression models, receipt of early dialysis was associated with lower odds of ED visits (OR, 0.80; 95% CI, 0.67-0.96; P=0.01) and hospitalizations (OR, 0.79; 95% CI, 0.66-0.94; P=0.01) in the week of the storm and 30-day mortality (OR, 0.72; 95% CI, 0.52-0.997; P=0.048). Inability to determine which patients were offered early dialysis and declined and whether important unmeasured patient characteristics are associated with receipt of early dialysis. Patients who received early dialysis had significantly lower odds of having an ED visit and hospitalization in the week of the storm and of

  15. John Dique: dialysis pioneer and political advocate.

    Science.gov (United States)

    George, Charles R P

    2016-02-01

    John Dique (1915-1995) epitomized the internationalism of medicine, the intellectual and manual dexterity of many pioneers of dialysis, and the social concern evinced by many nephrologists. Born in Burma of French, German, British and Indian ancestry; educated in India; an Anglo-Indian who described himself as British without ever having visited Britain; he moved to Australia in 1948 to escape the murderous inter-ethnic conflict that befell multicultural India as it and Pakistan became independent. Settling in Brisbane, he pioneered several novel medical techniques. After inventing some simple equipment to facilitate intravenous therapy, he established a neonatal exchange blood transfusion programme. Then, between 1954 and 1963, he personally constructed and operated two haemodialysis machines with which to treat patients suffering from acute renal failure, the first such treatment performed in Australasia. His patients survival results were, for the era, remarkable. He subsequently helped found the Royal Australasian College of Pathologists and went on to establish a successful private pathology practice. The latter years of his life, however, saw him become a social and political advocate. He fiercely opposed the emerging ideologies of multiculturalism and social liberalism that, he predicted, would seriously damage the national fabric of Western society. Public vilification ensued, his medical achievements disregarded. It does seem likely, however, that in none of the areas that he touched - whether medical, social, or political - has the last word yet been said.

  16. Infantile cystinosis: From dialysis to renal transplantation

    Directory of Open Access Journals (Sweden)

    Manel Jellouli

    2017-01-01

    Full Text Available Cystinosis is an autosomal recessive, lysosomal storage disease characterised by the accumulation of the amino acid cystine in different organs and tissues. It is a multisystemic disease that can present with renal and extra-renal manifestations. In this report, we present the first case of transplanted nephropathic cystinosis in a Tunisian child. A 4-year-old Tunisian boy born to nonconsanguineous parents, was treated in our medical services in 1990 for cystinosis. Since the age of five months, he developed symptoms of severe weight loss, vomiting, dehydration, and polyuria. He manifested the Toni Debré Fanconi syndrome. Slit lamp examination of the anterior segment of both eyes revealed fine, shiny crystal-like deposits diffusely distributed in the corneal epithelium and the stroma. Our patient had renal failure. At the age of seven, he reached terminal chronic renal failure and was treated with peritoneal dialysis. Hemodialysis was started at the age of nine years. At the age of 13 years, he received a renal transplantation and was started on cysteamine 1999, five months after the renal transplantation. Currently, the patient is 28-year-old. The graft has survived 15 years after the transplantation. Renal functions were stable with a serum creatinine of 123 μmol/L at last follow-up.

  17. Hemodynamic Simulations in Dialysis Access Fistulae

    Science.gov (United States)

    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.

  18. Examining Depression in Patients on Dialysis.

    Science.gov (United States)

    Treadwell, Allison A

    2017-01-01

    This study measured the prevalence of depression in 39 patients on hemodialysis and peritoneal dialysis in two urban outpatient facilities in the southeastern United States. Additionally, it evaluated the number of patients who sought and scheduled a mental health evaluation after screening and education. The prevalence of mild to severely depressed individuals among participants in this study was 36%, affirming previous findings of depressive symptoms in the ESRD population. Results suggest that patients with ESRD are at a higher risk for depression than the general population. The effects of depression may exacerbate ESRD symptoms, affect treatment adherence, and increase hospitalizations and morbidity. It is likely that screening, diagnosing, and treating depression will be associated with improvement in quality and quantity of life. The practicality of using the screening procedure may improve the detection of depression in this population. However, only a fraction of identified patients in this study pursued further mental health evaluation within the 45-day period. Continued research is needed to identify barriers to seeking mental health consultation and treatment in this community. Copyright© by the American Nephrology Nurses Association.

  19. Numerical Verification Of Equilibrium Chemistry

    International Nuclear Information System (INIS)

    Piro, Markus; Lewis, Brent; Thompson, William T.; Simunovic, Srdjan; Besmann, Theodore M.

    2010-01-01

    A numerical tool is in an advanced state of development to compute the equilibrium compositions of phases and their proportions in multi-component systems of importance to the nuclear industry. The resulting software is being conceived for direct integration into large multi-physics fuel performance codes, particularly for providing boundary conditions in heat and mass transport modules. However, any numerical errors produced in equilibrium chemistry computations will be propagated in subsequent heat and mass transport calculations, thus falsely predicting nuclear fuel behaviour. The necessity for a reliable method to numerically verify chemical equilibrium computations is emphasized by the requirement to handle the very large number of elements necessary to capture the entire fission product inventory. A simple, reliable and comprehensive numerical verification method is presented which can be invoked by any equilibrium chemistry solver for quality assurance purposes.

  20. Equilibrium ignition for ICF capsules

    International Nuclear Information System (INIS)

    Lackner, K.S.; Colgate, S.A.; Johnson, N.L.; Kirkpatrick, R.C.; Menikoff, R.; Petschek, A.G.

    1993-01-01

    There are two fundamentally different approaches to igniting DT fuel in an ICF capsule which can be described as equilibrium and hot spot ignition. In both cases, a capsule which can be thought of as a pusher containing the DT fuel is imploded until the fuel reaches ignition conditions. In comparing high-gain ICF targets using cryogenic DT for a pusher with equilibrium ignition targets using high-Z pushers which contain the radiation. The authors point to the intrinsic advantages of the latter. Equilibrium or volume ignition sacrifices high gain for lower losses, lower ignition temperature, lower implosion velocity and lower sensitivity of the more robust capsule to small fluctuations and asymmetries in the drive system. The reduction in gain is about a factor of 2.5, which is small enough to make the more robust equilibrium ignition an attractive alternative

  1. On the local equilibrium condition

    International Nuclear Information System (INIS)

    Hessling, H.

    1994-11-01

    A physical system is in local equilibrium if it cannot be distinguished from a global equilibrium by ''infinitesimally localized measurements''. This should be a natural characterization of local equilibrium, but the problem is to give a precise meaning to the qualitative phrase ''infinitesimally localized measurements''. A solution is suggested in form of a Local Equilibrium Condition (LEC), which can be applied to linear relativistic quantum field theories but not directly to selfinteracting quantum fields. The concept of local temperature resulting from LEC is compared to an old approach to local temperature based on the principle of maximal entropy. It is shown that the principle of maximal entropy does not always lead to physical states if it is applied to relativistic quantum field theories. (orig.)

  2. A Strategic-Equilibrium Based

    Directory of Open Access Journals (Sweden)

    Gabriel J. Turbay

    2011-03-01

    Full Text Available The strategic equilibrium of an N-person cooperative game with transferable utility is a system composed of a cover collection of subsets of N and a set of extended imputations attainable through such equilibrium cover. The system describes a state of coalitional bargaining stability where every player has a bargaining alternative against any other player to support his corresponding equilibrium claim. Any coalition in the sable system may form and divide the characteristic value function of the coalition as prescribed by the equilibrium payoffs. If syndicates are allowed to form, a formed coalition may become a syndicate using the equilibrium payoffs as disagreement values in bargaining for a part of the complementary coalition incremental value to the grand coalition when formed. The emergent well known-constant sum derived game in partition function is described in terms of parameters that result from incumbent binding agreements. The strategic-equilibrium corresponding to the derived game gives an equal value claim to all players.  This surprising result is alternatively explained in terms of strategic-equilibrium based possible outcomes by a sequence of bargaining stages that when the binding agreements are in the right sequential order, von Neumann and Morgenstern (vN-M non-discriminatory solutions emerge. In these solutions a preferred branch by a sufficient number of players is identified: the weaker players syndicate against the stronger player. This condition is referred to as the stronger player paradox.  A strategic alternative available to the stronger players to overcome the anticipated not desirable results is to voluntarily lower his bargaining equilibrium claim. In doing the original strategic equilibrium is modified and vN-M discriminatory solutions may occur, but also a different stronger player may emerge that has eventually will have to lower his equilibrium claim. A sequence of such measures converges to the equal

  3. Knowledge and Practice of Hemodialysis Amongst Dialysis Nurses.

    Science.gov (United States)

    Manandhar, Dhiraj Narayan; Chhetri, Pramod Kumar; Poudel, Prakash; Baidya, Samir Keshari; Agrawaal, Krishna Kumar

    2017-01-01

    Dialysis nurses should have a good knowledge regarding hemodialysis treatment. The status of Nepalese dialysis nurses on this aspect is unknown. This study was done to assess the knowledge and practice on different aspects of the hemodialysis treatment. We distributed validated questionnaires to the participants in a biannual conference in Kathmandu on 24th September as most of the dialysis nurses attend the event. We calculated mean and standard deviation for continuous variables and frequencies and percentage for the responses and compared counseling with different parameters. Total 94 out of 116 participants who were giving care to dialysis patients were in the study. Total 39 (42%) received formal nursing training in hemodialysis and 71 (78%) respondents always counseled patients regarding fluid intake. A total of 37 (96%) trained nurses always counseled the importance of regular dialysis. Seventy-six (81.7%) respondents did counseling on vaccination against Hepatitis B. Counseling on vaccination against influenza and pneumococcus was 47 (50%). When comparing educational status, respondents below bachelor level did more frequent counseling than level above (P=0.03). All the respondents knew the importance of hand washing and BP monitoring during hemodialysis. Ninety-one (96.7%) respondents knew how to deal with BP changes during hemodialysis. Seventy-three (77.6%) respondents were very confident on managing complications. Only 31 (33%) respondents knew how to deal with patients on continuous ambulatory peritoneal dialysis. Dialysis nurses have knowledge on basic procedures of hemodialysis but there is a space for improvement in dealing with complications to provide quality service to hemodialysis patients.

  4. Thermodynamic evolution far from equilibrium

    Science.gov (United States)

    Khantuleva, Tatiana A.

    2018-05-01

    The presented model of thermodynamic evolution of an open system far from equilibrium is based on the modern results of nonequilibrium statistical mechanics, the nonlocal theory of nonequilibrium transport developed by the author and the Speed Gradient principle introduced in the theory of adaptive control. Transition to a description of the system internal structure evolution at the mesoscopic level allows a new insight at the stability problem of non-equilibrium processes. The new model is used in a number of specific tasks.

  5. Relevance of equilibrium in multifragmentation

    International Nuclear Information System (INIS)

    Furuta, Takuya; Ono, Akira

    2009-01-01

    The relevance of equilibrium in a multifragmentation reaction of very central 40 Ca + 40 Ca collisions at 35 MeV/nucleon is investigated by using simulations of antisymmetrized molecular dynamics (AMD). Two types of ensembles are compared. One is the reaction ensemble of the states at each reaction time t in collision events simulated by AMD, and the other is the equilibrium ensemble prepared by solving the AMD equation of motion for a many-nucleon system confined in a container for a long time. The comparison of the ensembles is performed for the fragment charge distribution and the excitation energies. Our calculations show that there exists an equilibrium ensemble that well reproduces the reaction ensemble at each reaction time t for the investigated period 80≤t≤300 fm/c. However, there are some other observables that show discrepancies between the reaction and equilibrium ensembles. These may be interpreted as dynamical effects in the reaction. The usual static equilibrium at each instant is not realized since any equilibrium ensemble with the same volume as that of the reaction system cannot reproduce the fragment observables

  6. Shape characteristics of equilibrium and non-equilibrium fractal clusters.

    Science.gov (United States)

    Mansfield, Marc L; Douglas, Jack F

    2013-07-28

    It is often difficult in practice to discriminate between equilibrium and non-equilibrium nanoparticle or colloidal-particle clusters that form through aggregation in gas or solution phases. Scattering studies often permit the determination of an apparent fractal dimension, but both equilibrium and non-equilibrium clusters in three dimensions frequently have fractal dimensions near 2, so that it is often not possible to discriminate on the basis of this geometrical property. A survey of the anisotropy of a wide variety of polymeric structures (linear and ring random and self-avoiding random walks, percolation clusters, lattice animals, diffusion-limited aggregates, and Eden clusters) based on the principal components of both the radius of gyration and electric polarizability tensor indicates, perhaps counter-intuitively, that self-similar equilibrium clusters tend to be intrinsically anisotropic at all sizes, while non-equilibrium processes such as diffusion-limited aggregation or Eden growth tend to be isotropic in the large-mass limit, providing a potential means of discriminating these clusters experimentally if anisotropy could be determined along with the fractal dimension. Equilibrium polymer structures, such as flexible polymer chains, are normally self-similar due to the existence of only a single relevant length scale, and are thus anisotropic at all length scales, while non-equilibrium polymer structures that grow irreversibly in time eventually become isotropic if there is no difference in the average growth rates in different directions. There is apparently no proof of these general trends and little theoretical insight into what controls the universal anisotropy in equilibrium polymer structures of various kinds. This is an obvious topic of theoretical investigation, as well as a matter of practical interest. To address this general problem, we consider two experimentally accessible ratios, one between the hydrodynamic and gyration radii, the other

  7. Vitamins in dialysis: who, when and how much?

    Science.gov (United States)

    Kosmadakis, George; Da Costa Correia, Enrique; Carceles, Odette; Somda, Frederic; Aguilera, Didier

    2014-05-01

    Despite the significant technical evolution of the blood purification methods, cardiovascular morbidity and mortality in dialysis patients is still several times higher than that observed in the general population. Vitamins are playing a crucial role in multiple key metabolic pathways. Due to multiple factors, dialysis patients present very often hypo- or hypervitaminosis for a broad range of vitamins. Dialysis in the context of renal replacement therapy is associated with a non-physiological potassium-sparing dietetic regime. Additionally, there is a non-selective intradialytic loss of micro- and macronutrients, deranged intracellular kinetics and gastrointestinal malabsorption due to uratemia. Frequent treatment with antibiotics due to infections associated with the acquired uremia-related immunosuppression may derange the vitamin-producing intestinal microflora. Certain agents prescribed in the context of renal failure or other conditions may reduce the absorption of vitamins from the gastrointestinal tract. These factors may deplete a dialysis patient from vitamins, especially the ones with antioxidant activity that may be associated with cardioprotective properties. In other cases, vitamins metabolized and excreted by the kidneys may be accumulated and exert toxic effects. The scope of this paper is to describe the main issues on vitamin therapy in dialysis patients in view of the ever contradictory opinions and practices.

  8. Reduction in slow intercompartmental clearance of urea during dialysis

    International Nuclear Information System (INIS)

    Bowsher, D.J.; Krejcie, T.C.; Avram, M.J.; Chow, M.J.; Del Greco, F.; Atkinson, A.J. Jr.

    1985-01-01

    The kinetics of urea and inulin were analyzed in five anesthetized dogs during sequential 2-hour periods before, during, and after hemodialysis. The distribution of both compounds after simultaneous intravenous injection was characterized by three-compartment models, and the total volumes of urea (0.66 +/- 0.05 L/kg) and inulin (0.19 +/- 0.01 L/kg) distribution were similar to expected values for total body water and extravascular space, respectively. Intercompartmental clearances calculated before dialysis were used to estimate blood flows to the fast and slow equilibrating compartments. In agreement with previous results, the sum of these flows was similar to cardiac output, averaging 101% of cardiac output measured before dialysis (range 72% to 135%). Dialysis was accompanied by reductions in the slow intercompartmental clearances of urea (81%) and inulin (47%), which reflected a 90% attenuation in blood flow supplying the slow equilibrating compartments. This was estimated to result in a 10% average reduction in the efficiency with which urea was removed by dialysis (range 2.0% to 16.4%). Mean arterial pressure fell by less than 5% during dialysis, but total peripheral resistance increased by 47% and cardiac output fell by 35%. In the postdialysis period, total peripheral resistance and cardiac output returned toward predialysis values, but blood flow to the slow equilibrating peripheral compartment was still reduced by 80%. These changes parallel activation of the renin-angiotensin system, but further studies are required to establish causality

  9. Disruptive technological advances in vascular access for dialysis: an overview.

    Science.gov (United States)

    Yeo, Wee-Song; Ng, Qin Xiang

    2017-11-29

    End-stage kidney disease (ESKD), one of the most prevalent diseases in the world and with increasing incidence, is associated with significant morbidity and mortality. Current available modes of renal replacement therapy (RRT) include dialysis and renal transplantation. Though renal transplantation is the preferred and ideal mode of RRT, this modality may not be available to all patients with ESKD. Moreover, renal transplant recipients are constantly at risk of complications associated with immunosuppression and immunosuppressant use, and posttransplant lymphoproliferative disorder. Dialysis may be the only available modality in certain patients. However, dialysis has its limitations, which include issues associated with lack of vascular access, risks of infections and vascular thrombosis, decreased quality of life, and absence of biosynthetic functions of the kidney. In particular, the creation and maintenance of hemodialysis vascular access in children poses a unique set of challenges to the pediatric nephrologist owing to the smaller vessel diameters and vascular hyperreactivity compared with adult patients. Vascular access issues continue to be one of the major limiting factors prohibiting the delivery of adequate dialysis in ESKD patients and is the Achilles' heel of hemodialysis. This review aims to provide a critical overview of disruptive technological advances and innovations for vascular access. Novel strategies in preventing neointimal hyperplasia, novel bioengineered products, grafts and devices for vascular access will be discussed. The potential impact of these solutions on improving the morbidity encountered by dialysis patients will also be examined.

  10. Insomnia in chronic renal patients on dialysis in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Al-Hejaili Fayez F

    2010-06-01

    Full Text Available Abstract Background Studies have shown that insomnia is a common sleep disorder among patients with end-stage renal disease (ESRD. This study aimed to assess the prevalence of insomnia in Saudi patients with ESRD who are on maintenance dialysis. Methods This was an observational cross-sectional study carried out over a period of five months in two hemodialysis centers in Saudi Arabia. To assess the prevalence of insomnia, we used the ICSD-2 definition. We also examined the association between insomnia and other sleep disorders, the underlying causes of renal failure, dialysis duration, dialysis shift, and other demographic data. Results Out of 227 enrolled patients, insomnia was reported by 60.8%. The mean patient age was 55.7 ± 17.2 years; 53.7% were male and 46.3% were female. Insomnia was significantly associated with female gender, afternoon hemodialysis, Restless Legs Syndrome, high risk for obstructive Sleep Apnea Syndrome and excessive daytime sleepiness (P-values: 0.05, 0.01, Conclusion Insomnia is common in dialysis patients and was significantly associated with other sleep disorders. Greater attention needs to be given to the care of dialysis patients with regard to the diagnosis and management of insomnia and associated sleep disorders.

  11. Intermittent Oral Versus Intravenous Alfacalcidol in Dialysis Patients

    Directory of Open Access Journals (Sweden)

    Mitwalli Ahmed

    2000-01-01

    Full Text Available Patients with end-stage renal failure (ESRF on maintenance dialysis, commonly develop secondary hyperparathyroidism and renal osteodystrophy (ROD. Alfacalcidol, taken orally or administered intravenously, is known to reverse these complications. In this study, 19 ESRF patients, who were on dialysis (13 on hemodialysis and six on peritoneal dialysis for longer than six months and having serum parathormone levels at least four times normal and serum calcium less than 2.1 mmol/L, were randomly allocated to treatment with oral or intravenous (i.v. alfacalcidol for a period of 12 months. There were six patients on hemodialysis (HD and three on peritoneal dialysis (PD in the oral treatment group while in the i.v. group there were seven patients on HD and three on PD. Clinical and serial biochemical assessments showed no statistically significant difference between the orally- and i.v.-treated patients in terms of suppressing secondary hyperparathyroidism and osteodystrophy. However, patients with features of mild ROD on bone histology, had more satisfactory changes in biochemistry when compared to others. Our results further support the use of intermittent oral alfacalcidol in ESRF patients because of its cost effectiveness, ease of administration and convenience, especially for peritoneal dialysis patients.

  12. Mineral Metabolic Abnormalities and Mortality in Dialysis Patients

    Directory of Open Access Journals (Sweden)

    Masanori Abe

    2013-03-01

    Full Text Available The survival rate of dialysis patients, as determined by risk factors such as hypertension, nutritional status, and chronic inflammation, is lower than that of the general population. In addition, disorders of bone mineral metabolism are independently related to mortality and morbidity associated with cardiovascular disease and fracture in dialysis patients. Hyperphosphatemia is an important risk factor of, not only secondary hyperparathyroidism, but also cardiovascular disease. On the other hand, the risk of death reportedly increases with an increase in adjusted serum calcium level, while calcium levels below the recommended target are not associated with a worsened outcome. Thus, the significance of target levels of serum calcium in dialysis patients is debatable. The consensus on determining optimal parathyroid function in dialysis patients, however, is yet to be established. Therefore, the contribution of phosphorus and calcium levels to prognosis is perhaps more significant. Elevated fibroblast growth factor 23 levels have also been shown to be associated with cardiovascular events and death. In this review, we examine the associations between mineral metabolic abnormalities including serum phosphorus, calcium, and parathyroid hormone and mortality in dialysis patients.

  13. Engagement in decision-making and patient satisfaction: a qualitative study of older patients' perceptions of dialysis initiation and modality decisions.

    Science.gov (United States)

    Ladin, Keren; Lin, Naomi; Hahn, Emily; Zhang, Gregory; Koch-Weser, Susan; Weiner, Daniel E

    2017-08-01

    Although shared decision-making (SDM) can better align patient preferences with treatment, barriers remain incompletely understood and the impact on patient satisfaction is unknown. This is a qualitative study with semistructured interviews. A purposive sample of prevalent dialysis patients ≥65 years of age at two facilities in Greater Boston were selected for diversity in time from initiation, race, modality and vintage. A codebook was developed and interrater reliability was 89%. Codes were discussed and organized into themes. A total of 31 interviews with 23 in-center hemodialysis patients, 1 home hemodialysis patient and 7 peritoneal dialysis patients were completed. The mean age was 76 ± 9 years. Two dominant themes (with related subthemes) emerged: decision-making experiences and satisfaction, and barriers to SDM. Subthemes included negative versus positive decision-making experiences, struggling for autonomy, being a 'good patient' and lack of choice. In spite of believing that dialysis initiation should be the patient's choice, no patients perceived that they had made a choice. Patients explained that this is due to the perception of imminent death or that the decision to start dialysis belonged to physicians. Clinicians and family frequently overrode patient preferences, with patient autonomy honored mostly to select dialysis modality. Poor decision-making experiences were associated with low treatment satisfaction. Despite recommendations for SDM, many older patients were unaware that dialysis initiation was voluntary, held mistaken beliefs about their prognosis and were not engaged in decision-making, resulting in poor satisfaction. Patients desired greater information, specifically focusing on the acuity of their choice, prognosis and goals of care. © The Author 2016. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

  14. 3D equilibrium codes for mirror machines

    International Nuclear Information System (INIS)

    Kaiser, T.B.

    1983-01-01

    The codes developed for cumputing three-dimensional guiding center equilibria for quadrupole tandem mirrors are discussed. TEBASCO (Tandem equilibrium and ballooning stability code) is a code developed at LLNL that uses a further expansion of the paraxial equilibrium equation in powers of β (plasma pressure/magnetic pressure). It has been used to guide the design of the TMX-U and MFTF-B experiments at Livermore. Its principal weakness is its perturbative nature, which renders its validity for high-β calculation open to question. In order to compute high-β equilibria, the reduced MHD technique that has been proven useful for determining toroidal equilibria was adapted to the tandem mirror geometry. In this approach, the paraxial expansion of the MHD equations yields a set of coupled nonlinear equations of motion valid for arbitrary β, that are solved as an initial-value problem. Two particular formulations have been implemented in computer codes developed at NYU/Kyoto U and LLNL. They differ primarily in the type of grid, the location of the lateral boundary and the damping techniques employed, and in the method of calculating pressure-balance equilibrium. Discussions on these codes are presented in this paper. (Kato, T.)

  15. Local Equilibrium and Retardation Revisited.

    Science.gov (United States)

    Hansen, Scott K; Vesselinov, Velimir V

    2018-01-01

    In modeling solute transport with mobile-immobile mass transfer (MIMT), it is common to use an advection-dispersion equation (ADE) with a retardation factor, or retarded ADE. This is commonly referred to as making the local equilibrium assumption (LEA). Assuming local equilibrium, Eulerian textbook treatments derive the retarded ADE, ostensibly exactly. However, other authors have presented rigorous mathematical derivations of the dispersive effect of MIMT, applicable even in the case of arbitrarily fast mass transfer. We resolve the apparent contradiction between these seemingly exact derivations by adopting a Lagrangian point of view. We show that local equilibrium constrains the expected time immobile, whereas the retarded ADE actually embeds a stronger, nonphysical, constraint: that all particles spend the same amount of every time increment immobile. Eulerian derivations of the retarded ADE thus silently commit the gambler's fallacy, leading them to ignore dispersion due to mass transfer that is correctly modeled by other approaches. We then present a particle tracking simulation illustrating how poor an approximation the retarded ADE may be, even when mobile and immobile plumes are continually near local equilibrium. We note that classic "LEA" (actually, retarded ADE validity) criteria test for insignificance of MIMT-driven dispersion relative to hydrodynamic dispersion, rather than for local equilibrium. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

  16. Validation of equilibrium tools on the COMPASS tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Urban, J., E-mail: urban@ipp.cas.cz [Institute of Plasma Physics ASCR, Za Slovankou 3, 182 00 Praha 8 (Czech Republic); Appel, L.C. [CCFE, Culham Science Centre, Abingdon, Oxfordshire (United Kingdom); Artaud, J.F. [CEA, IRFM, F-13108 Saint Paul Lez Durance (France); Faugeras, B. [Laboratoire J.A. Dieudonné, UMR 7351, Université de Nice Sophia-Antipolis, Parc Valrose, 06108 Nice Cedex 02 (France); Havlicek, J. [Institute of Plasma Physics ASCR, Za Slovankou 3, 182 00 Praha 8 (Czech Republic); Department of Surface and Plasma Science, Faculty of Mathematics and Physics, Charles University in Prague, V Holešovičkách 2, 180 00 Praha 8 (Czech Republic); Komm, M. [Institute of Plasma Physics ASCR, Za Slovankou 3, 182 00 Praha 8 (Czech Republic); Lupelli, I. [CCFE, Culham Science Centre, Abingdon, Oxfordshire (United Kingdom); Peterka, M. [Institute of Plasma Physics ASCR, Za Slovankou 3, 182 00 Praha 8 (Czech Republic); Department of Surface and Plasma Science, Faculty of Mathematics and Physics, Charles University in Prague, V Holešovičkách 2, 180 00 Praha 8 (Czech Republic)

    2015-10-15

    Highlights: • Three equilibrium codes—EFIT++, FREEBIE and VacTH—have been successfully set up and validated on COMPASS. • FREEBIE can predictively calculate the equilibrium and corresponding poloidal field coil currents. • EFIT++ can reconstruct equilibria generated by FREEBIE from synthetic, optionally noisy diagnostic data. • VacTH is a promising tool for real time plasma shape reconstruction. • Optimized parameters are estimated for EFIT++ and VacTH by a statistical analysis. - Abstract: Various MHD (magnetohydrodynamic) equilibrium tools, some of which being recently developed or considerably updated, are used on the COMPASS tokamak at IPP Prague. MHD equilibrium is a fundamental property of the tokamak plasma, whose knowledge is required for many diagnostics and modelling tools. Proper benchmarking and validation of equilibrium tools is thus key for interpreting and planning tokamak experiments. We present here benchmarks and comparisons to experimental data of the EFIT++ reconstruction code (Appel et al., 2006), the free-boundary equilibrium code FREEBIE (Artaud and Kim, 2012), and a rapid plasma boundary reconstruction code VacTH (Faugeras et al., 2014). We demonstrate that FREEBIE can calculate the equilibrium and corresponding poloidal field (PF) coils currents consistently with EFIT++ reconstructions from experimental data. Both EFIT++ and VacTH can reconstruct equilibria generated by FREEBIE from synthetic, optionally noisy diagnostic data. Hence, VacTH is suitable for real-time control. Optimum reconstruction parameters are estimated.

  17. Frailty in Chinese Peritoneal Dialysis Patients: Prevalence and Prognostic Significance

    Directory of Open Access Journals (Sweden)

    Jack Kit-Chung Ng

    2016-10-01

    Full Text Available Background/Aims: Previous studies showed that frailty is prevalent in both pre-dialysis and dialysis patients. However, the prevalence and prognostic implication of frailty in Chinese peritoneal dialysis (PD patients remain unknown. Methods: We used a validated questionnaire to determine the Frailty Score of 193 unselected prevalent PD patients. All patients were then followed for 2 years for their need of hospitalization and mortality. Results: Amongst the 193 patients, 134 (69.4% met the criteria of being frail. Frailty Score significantly correlated with Charlson's comorbidity score (r = 0.40, p Conclusions: Frailty is prevalent among Chinese PD patients. Frail PD patients have a high risk of requiring hospitalization and their hospital stay tends to be prolonged. Early identification may allow timely intervention to prevent adverse health outcomes in this group of patients.

  18. Challenges of ECG monitoring and ECG interpretation in dialysis units.

    Science.gov (United States)

    Poulikakos, Dimitrios; Malik, Marek

    Patients on hemodialysis (HD) suffer from high cardiovascular morbidity and mortality due to high rates of coronary artery disease and arrhythmias. Electrocardiography (ECG) is often performed in the dialysis units as part of routine clinical assessment. However, fluid and electrolyte changes have been shown to affect all ECG morphologies and intervals. ECG interpretation thus depends on the time of the recording in relation to the HD session. In addition, arrhythmias during HD are common, and dialysis-related ECG artifacts mimicking arrhythmias have been reported. Studies using advanced ECG analyses have examined the impact of the HD procedure on selected repolarization descriptors and heart rate variability indices. Despite the challenges related to the impact of the fluctuant fluid and electrolyte status on conventional and advanced ECG parameters, further research in ECG monitoring during dialysis has the potential to provide clinically meaningful and practically useful information for diagnostic and risk stratification purposes. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.

  19. Tailoring peritoneal dialysis fluid for optimal acid-base targets.

    Science.gov (United States)

    Feriani, Mariano

    2009-01-01

    Mild derangements of acid-base status are common features in peritoneal dialysis patients, metabolic acidosis being the most frequent alteration. One of the main tasks of dialysis is to correct these derangements and the target is the normalization of the acid-base parameters since they affect several organs and functions. Since factors affecting acid-base homeostasis are intrinsic characteristics of the individual patient (metabolic acid production, distribution space for bicarbonate, dialytic prescription, etc.), it is not surprising that only relatively few patients achieve the normal range. Only a certain modulation of buffer infusion by using different buffer concentrations in the dialysis fluid may ensure a good correction in a large percentage of patients.

  20. Examination of dialysis patients with the aminophenazone breath test

    International Nuclear Information System (INIS)

    Heinrich, H.G.; Adler, D.; Hornak, H.; Wuenschmann, H.J.; Mayer, W.K.

    1989-01-01

    In 12 endstage kidney disease patients (8 without and 4 with liver diseases) the activities of cytochrome P 450 -dependent mixed functional oxidases system (MFO) of the liver were studied by using the 14 C-aminophenazone breath test before and after dialysis. The results showed that uremia seems to have a pressing influence on MFO activity. The activity was only significantly increased after dialysis in the group of patients without liver diseases. The MFO activity was reduced in patients with liver diseases. This is a restriction of the hepatic metabolic demethylation capacity. It is unclear if the 14 C-aminophenazone breath test in dialysis patients is qualified to estimate metabolic capacity of the liver. Differentiation between the influence of uremia and of the liver disease on the alteration of MFO activity cannot be made. (author)

  1. Nonadherence in dialysis patients: prevalence, measurement, outcome, and psychological determinants.

    Science.gov (United States)

    Clark, Sarah; Farrington, Ken; Chilcot, Joseph

    2014-01-01

    Nonadherence to aspects of the management of End-Stage Kidney Disease (ESKD) is common. Estimates of nonadherence vary with assessment method. Whilst readily available and free from report bias, physiological proxies-frequently used as measures of adherence-are often confounded by clinical factors including residual kidney function and dialysis adequacy. Despite variation in estimates of its prevalence, it is clear that suboptimal adherence to dialysis prescriptions, medication and diet can lead to adverse clinical outcomes. Several factors can help explain nonadherence in ESKD including mood, self-efficacy, social support, illness, and treatment perceptions. Psychological interventions have been shown to improve ESKD adherence, yet achieving long-term behavior change remains challenging. Identifying individuals who struggle to adhere to aspects of the dialysis regime, and tailoring theory-led interventions to improve and support adherence is a clear clinical need requiring further empirical enquiry. © 2013 Wiley Periodicals, Inc.

  2. Comparison of outcomes for veterans receiving dialysis care from VA and non-VA providers

    Directory of Open Access Journals (Sweden)

    Wang Virginia

    2013-01-01

    Full Text Available Abstract Background Demand for dialysis treatment exceeds its supply within the Veterans Health Administration (VA, requiring VA to outsource dialysis care by purchasing private sector dialysis for veterans on a fee-for-service basis. It is unclear whether outcomes are similar for veterans receiving dialysis from VA versus non-VA providers. We assessed the extent of chronic dialysis treatment utilization and differences in all-cause hospitalizations and mortality between veterans receiving dialysis from VA versus VA-outsourced providers. Methods We constructed a retrospective cohort of veterans in 2 VA regions who received chronic dialysis treatment financed by VA between January 2007 and December 2008. From VA administrative data, we identified veterans who received outpatient dialysis in (1 VA, (2 VA-outsourced settings, or (3 both (“dual” settings. In adjusted analyses, we used two-part and logistic regression to examine associations between dialysis setting and all-cause hospitalization and mortality one-year from veterans’ baseline dialysis date. Results Of 1,388 veterans, 27% received dialysis exclusively in VA, 47% in VA-outsourced settings, and 25% in dual settings. Overall, half (48% were hospitalized and 12% died. In adjusted analysis, veterans in VA-outsourced settings incurred fewer hospitalizations and shorter hospital stays than users of VA due to favorable selection. Dual-system dialysis patients had lower one-year mortality than veterans receiving VA dialysis. Conclusions VA expenditures for “buying” outsourced dialysis are high and increasing relative to “making” dialysis treatment within its own system. Outcomes comparisons inform future make-or-buy decisions and suggest the need for VA to consider veterans’ access to care, long-term VA savings, and optimal patient outcomes in its placement decisions for dialysis services.

  3. Comparison of outcomes for veterans receiving dialysis care from VA and non-VA providers.

    Science.gov (United States)

    Wang, Virginia; Maciejewski, Matthew L; Patel, Uptal D; Stechuchak, Karen M; Hynes, Denise M; Weinberger, Morris

    2013-01-18

    Demand for dialysis treatment exceeds its supply within the Veterans Health Administration (VA), requiring VA to outsource dialysis care by purchasing private sector dialysis for veterans on a fee-for-service basis. It is unclear whether outcomes are similar for veterans receiving dialysis from VA versus non-VA providers. We assessed the extent of chronic dialysis treatment utilization and differences in all-cause hospitalizations and mortality between veterans receiving dialysis from VA versus VA-outsourced providers. We constructed a retrospective cohort of veterans in 2 VA regions who received chronic dialysis treatment financed by VA between January 2007 and December 2008. From VA administrative data, we identified veterans who received outpatient dialysis in (1) VA, (2) VA-outsourced settings, or (3) both ("dual") settings. In adjusted analyses, we used two-part and logistic regression to examine associations between dialysis setting and all-cause hospitalization and mortality one-year from veterans' baseline dialysis date. Of 1,388 veterans, 27% received dialysis exclusively in VA, 47% in VA-outsourced settings, and 25% in dual settings. Overall, half (48%) were hospitalized and 12% died. In adjusted analysis, veterans in VA-outsourced settings incurred fewer hospitalizations and shorter hospital stays than users of VA due to favorable selection. Dual-system dialysis patients had lower one-year mortality than veterans receiving VA dialysis. VA expenditures for "buying" outsourced dialysis are high and increasing relative to "making" dialysis treatment within its own system. Outcomes comparisons inform future make-or-buy decisions and suggest the need for VA to consider veterans' access to care, long-term VA savings, and optimal patient outcomes in its placement decisions for dialysis services.

  4. Equilibrium between Different Coordination Geometries in Oxidovanadium(IV) Complexes

    Science.gov (United States)

    Ugone, Valeria; Garribba, Eugenio; Micera, Giovanni; Sanna, Daniele

    2015-01-01

    In this laboratory activity, the equilibrium between square pyramidal and octahedral V(IV)O[superscript 2+] complexes is described. We propose a set of experiments to synthesize and characterize two types of V(IV)O[superscript 2+] complexes. The experiment allows great flexibility and may be effectively used at a variety of levels and the activity…

  5. Phosphate binding therapy in dialysis patients: focus on lanthanum carbonate

    Directory of Open Access Journals (Sweden)

    Ismail A Mohammed

    2008-11-01

    Full Text Available Ismail A Mohammed, Alastair J HutchisonManchester Institute of Nephrology and Transplantation, Manchester Royal Infirmary, Oxford Road, Manchester, UKAbstract: Hyperphosphatemia is an inevitable consequence of end stage chronic kidney disease and is present in the majority of dialysis patients. Recent observational data has associated hyperphosphatemia with increased cardiovascular mortality among dialysis patients. Dietary restriction of phosphate and current dialysis prescription practices are not enough to maintain serum phosphate levels within the recommended range so that the majority of dialysis patients require oral phosphate binders. Unfortunately, conventional phosphate binders are not reliably effective and are associated with a range of limitations and side effects. Aluminium-containing agents are highly efficient but no longer widely used because of well established and proven toxicity. Calcium based salts are inexpensive, effective and most widely used but there is now concern about their association with hypercalcemia and vascular calcification. Sevelamer hydrochloride is associated with fewer adverse effects, but a large pill burden and high cost are limiting factors to its wider use. In addition, the efficacy of sevelamer as a monotherapy in lowering phosphate to target levels in severe hyperphosphatemia remains debatable. Lanthanum carbonate is a promising new non-aluminium, calcium-free phosphate binder. Preclinical and clinical studies have demonstrated a good safety profile, and it appears well tolerated and effective in reducing phosphate levels in dialysis patients. Its identified adverse events are apparently mild to moderate in severity and mostly GI related. It appears to be effective as a monotherapy, with a reduced pill burden, but like sevelamer, it is significantly more expensive than calcium-based binders. Data on its safety profile over 6 years of treatment are now available.Keywords: hyperphosphatemia, lanthanum

  6. Equilibrium Arrival Times to Queues

    DEFF Research Database (Denmark)

    Breinbjerg, Jesper; Østerdal, Lars Peter

    We consider a non-cooperative queueing environment where a finite number of customers independently choose when to arrive at a queueing system that opens at a given point in time and serves customers on a last-come first-serve preemptive-resume (LCFS-PR) basis. Each customer has a service time...... requirement which is identically and independently distributed according to some general probability distribution, and they want to complete service as early as possible while minimizing the time spent in the queue. In this setting, we establish the existence of an arrival time strategy that constitutes...... a symmetric (mixed) Nash equilibrium, and show that there is at most one symmetric equilibrium. We provide a numerical method to compute this equilibrium and demonstrate by a numerical example that the social effciency can be lower than the effciency induced by a similar queueing system that serves customers...

  7. Compact torus theory: MHD equilibrium and stability

    International Nuclear Information System (INIS)

    Barnes, D.C.; Seyler, C.E.; Anderson, D.V.

    1979-01-01

    Field reversed theta pinches have demonstrated the production and confinement of compact toroidal configurations with surprisingly good MHD stability. In these observations, the plasma is either lost by diffusion or by the loss of the applied field or is disrupted by an n = 2 (where n is the toroidal mode number) rotating instability only after 30 to 100 MHD times, when the configuration begins to rotate rigidly above a critical speed. These experiments have led one to investigate the equilibrium, stability, and rotation of a very elongated, toroidally axisymmetric configuration with no toroidal field. Many of the above observations are explained by recent results of these investigations which are summarized

  8. How to preserve residual renal function in patients with chronic kidney disease and on dialysis?

    NARCIS (Netherlands)

    Krediet, Raymond T.

    2006-01-01

    A review is given on various aspects of GFR in patients with chronic kidney disease and in dialysis patients. These include the measurement of GFR, measures to preserve GFR in chronic kidney disease and dialysis, the importance of residual GFR in dialysis patients and factors that influence GFR in

  9. Is protein-energy intake adequate during dialysis treatment in hemodialysis patients ?

    Directory of Open Access Journals (Sweden)

    Trudeke (G I. Struijk-Wielinga

    2012-06-01

    Conclusion: Protein and energy intake of hemodialysis patients is lower than their daily needs. On non dialysis days intake is even lower than on dialysis days. The meals consumed during dialysis treatment contain enough energy but not enough protein to meet requirements.

  10. The Association Between Glucose Exposure and the Risk of Peritonitis in Peritoneal Dialysis Patients.

    Science.gov (United States)

    van Diepen, Anouk T N; van Esch, Sadie; Struijk, Dirk G; Krediet, Raymond T

    ♦ Little or no clinical evidence is available on the association between glucose exposure and peritoneal host defense in peritoneal dialysis (PD) patients. The objective of the present study was to quantify the exposure to glucose during the first year on PD and investigate the association with subsequent peritonitis. ♦ We analyzed prospectively collected demographic and peritonitis data from incident adult PD patients between 1990 and 2010. For the present study, we conducted a review of both in- and outpatient medical records of all patients to obtain their day-to-day dialysis schemes during the first year on PD. From these data, the average exposure to glucose was quantified. The exposure was stratified into low- and high-glucose groups based on the median, analyzed per standard deviation and in quartiles. Cox proportional hazard models were used to calculate crude and adjusted hazard ratios (HRs) and 95% confidence intervals for the association between glucose exposure and peritonitis. Adjustments were made for age, sex, primary kidney disease, diabetes mellitus, Davies comorbidity score and the treatment period. ♦ In total, 230 patients were included in the study of whom 151 (66%) experienced a first peritonitis episode. The median follow-up time was 2.6 years (interquartile range [IQR]: 1.9 - 3.8) in the low-glucose group and 3.1 (IQR: 2.1 - 4.2) in the high-glucose group. After adjustment for confounding factors, no association between high glucose exposure and the risk of peritonitis was found (HR: 0.81; 0.55 - 1.17). No association was present when glucose exposure was analyzed per standard deviation (SD) (HR: 0.98; 0.79 - 1.21) or patient quartiles were applied. No association was identified between glucose exposure and severe peritonitis, Staphylococcus aureus peritonitis, or a peritonitis episode that lasted more than 14 days. ♦ Exposure to glucose is not associated with an increased risk of peritonitis. The equilibrium between glycemic harm to

  11. Fate of patients during the first year of dialysis

    Directory of Open Access Journals (Sweden)

    Selma Siham El Khayat

    2013-01-01

    Full Text Available Care in dialysis is often associated with significant morbidity and mortality during the first year. Knowledge of its magnitude and causes could improve the prognosis of these patients. The aim of this study was to evaluate the survival and morbidity during the first year of dialysis for patients who initiated their dialysis between January 1, 2009 and December 31, 2009 and to study their possible correlation with baseline status at the beginning of treatment. A multi-center retrospective study was conducted in 11 dialysis centers. Clinical data at the beginning of dialysis and during the following year were collected. Mortality and morbidity risk factors were assessed by comparing different groups. Statistical analysis was performed with SPSS version 11. This study involved 134 patients, 79 men and 55 women, of whom 132 were on hemodialysis and two patients were on peritoneal dialysis. The mean age at initiation of treatment was 54.37 ± 18.09 years. Initial causes of nephropathy were dominated by diabetes (44.02% and hypertension (11.19%. Among these patients, 39.55% had never received prior nephrological follow-up and 64.92% had started renal replacement therapy on an emergency basis. The initial clinical state was dominated by the presence of hypertension (50.74%, diabetes (44.02%, coronary insufficiency (13.43% and heart failure (7.46%. Only 26.86% of the incident patients showed no comorbidity. During the first year of follow-up, 37.31% of the patients experienced at least one episode of comorbidity. Hospitalization was necessary in about half of these cases (17.91% of all patients. The overall mortality rate was 14.17%. One patient received a kidney transplant. The mortality rate in the first year of dialysis was lower in our study than in other series. Regular nephrological follow-up of these patients before they reach end-stage could have a significant influence on survival in dialysis.

  12. Psychological distress and treatment adherence among children on dialysis.

    Science.gov (United States)

    Simoni, J M; Asarnow, J R; Munford, P R; Koprowski, C M; Belin, T R; Salusky, I B

    1997-10-01

    Among 23 pediatric renal dialysis patients, we obtained self-reported assessments of psychological adjustment and biochemical and subjective ratings of adherence. Findings indicate elevated levels of depressive symptoms and substantial nonadherence. Depressive symptoms were associated with higher levels of hopelessness, more negative self-perceptions, and more depressogenic attributional style. The psychological adjustment measures did not significantly correlate with adherence. Nonsignificant associations among different measures of adherence underscore its multifaceted nature. Implications for monitoring the adjustment of children on dialysis, assessing adherence, and future research are discussed.

  13. Brain gamma-aminobutyric acid deficiency in dialysis encephalopathy.

    Science.gov (United States)

    Sweeney, V P; Perry, T L; Price, J D; Reeve, C E; Godolphin, W J; Kish, S J

    1985-02-01

    We measured levels of gamma-aminobutyric acid (GABA) in the CSF and in the autopsied brain of patients with dialysis encephalopathy. GABA concentrations were low in the CSF of three of five living patients. Mean GABA content was reduced by 30 to 50% in five brain regions (frontal, occipital, and cerebellar cortex, caudate nucleus, and medial dorsal thalamus) in five fatal cases. GABA content was normal in brain regions where GABA is characteristically reduced in Huntington's disease. Choline acetyltransferase activity was diminished (by 25 to 35%) in cerebral cortex of the dialysis encephalopathy patients.

  14. Peritoneal Dialysis Access Revision in Children: Causes, Interventions, and Outcomes.

    Science.gov (United States)

    Borzych-Duzalka, Dagmara; Aki, T Fazil; Azocar, Marta; White, Colin; Harvey, Elizabeth; Mir, Sevgi; Adragna, Marta; Serdaroglu, Erkin; Sinha, Rajiv; Samaille, Charlotte; Vanegas, Juan Jose; Kari, Jameela; Barbosa, Lorena; Bagga, Arvind; Galanti, Monica; Yavascan, Onder; Leozappa, Giovanna; Szczepanska, Maria; Vondrak, Karel; Tse, Kei-Chiu; Schaefer, Franz; Warady, Bradley A

    2017-01-06

    Little published information is available about access failure in children undergoing chronic peritoneal dialysis. Our objectives were to evaluate frequency, risk factors, interventions, and outcome of peritoneal dialysis access revision. Data were derived from 824 incident and 1629 prevalent patients from 105 pediatric nephrology centers enrolled in the International Pediatric Peritoneal Dialysis Network Registry between 2007 and 2015. In total, 452 access revisions were recorded in 321 (13%) of 2453 patients over 3134 patient-years of follow-up, resulting in an overall access revision rate of 0.14 per treatment year. Among 824 incident patients, 186 (22.6%) underwent 188 access revisions over 1066 patient-years, yielding an access revision rate of 0.17 per treatment year; 83% of access revisions in incident patients were reported within the first year of peritoneal dialysis treatment. Catheter survival rates in incident patients were 84%, 80%, 77%, and 73% at 12, 24, 36, and 48 months, respectively. By multivariate logistic regression analysis, risk of access revision was associated with younger age (odds ratio, 0.93; 95% confidence interval, 0.92 to 0.95; P<0.001), diagnosis of congenital anomalies of the kidney and urinary tract (odds ratio, 1.28; 95% confidence interval, 1.03 to 1.59; P=0.02), coexisting ostomies (odds ratio, 1.42; 95% confidence interval, 1.07 to 1.87; P=0.01), presence of swan neck tunnel with curled intraperitoneal portion (odds ratio, 1.30; 95% confidence interval, 1.04 to 1.63; P=0.02), and high gross national income (odds ratio, 1.10; 95% confidence interval, 1.02 to 1.19; P=0.01). Main reasons for access revisions included mechanical malfunction (60%), peritonitis (16%), exit site infection (12%), and leakage (6%). Need for access revision increased the risk of peritoneal dialysis technique failure or death (hazard ratio, 1.35; 95% confidence interval, 1.10 to 1.65; P=0.003). Access dysfunction due to mechanical causes doubled the risk

  15. Peritoneal Dialysis Access Revision in Children: Causes, Interventions, and Outcomes

    Science.gov (United States)

    Aki, T. Fazil; Azocar, Marta; White, Colin; Harvey, Elizabeth; Mir, Sevgi; Adragna, Marta; Serdaroglu, Erkin; Sinha, Rajiv; Samaille, Charlotte; Vanegas, Juan Jose; Kari, Jameela; Barbosa, Lorena; Bagga, Arvind; Galanti, Monica; Yavascan, Onder; Leozappa, Giovanna; Szczepanska, Maria; Vondrak, Karel; Tse, Kei-Chiu; Schaefer, Franz; Warady, Bradley A.

    2017-01-01

    Background and objectives Little published information is available about access failure in children undergoing chronic peritoneal dialysis. Our objectives were to evaluate frequency, risk factors, interventions, and outcome of peritoneal dialysis access revision. Design, setting, participants, & measurements Data were derived from 824 incident and 1629 prevalent patients from 105 pediatric nephrology centers enrolled in the International Pediatric Peritoneal Dialysis Network Registry between 2007 and 2015. Results In total, 452 access revisions were recorded in 321 (13%) of 2453 patients over 3134 patient-years of follow-up, resulting in an overall access revision rate of 0.14 per treatment year. Among 824 incident patients, 186 (22.6%) underwent 188 access revisions over 1066 patient-years, yielding an access revision rate of 0.17 per treatment year; 83% of access revisions in incident patients were reported within the first year of peritoneal dialysis treatment. Catheter survival rates in incident patients were 84%, 80%, 77%, and 73% at 12, 24, 36, and 48 months, respectively. By multivariate logistic regression analysis, risk of access revision was associated with younger age (odds ratio, 0.93; 95% confidence interval, 0.92 to 0.95; P<0.001), diagnosis of congenital anomalies of the kidney and urinary tract (odds ratio, 1.28; 95% confidence interval, 1.03 to 1.59; P=0.02), coexisting ostomies (odds ratio, 1.42; 95% confidence interval, 1.07 to 1.87; P=0.01), presence of swan neck tunnel with curled intraperitoneal portion (odds ratio, 1.30; 95% confidence interval, 1.04 to 1.63; P=0.02), and high gross national income (odds ratio, 1.10; 95% confidence interval, 1.02 to 1.19; P=0.01). Main reasons for access revisions included mechanical malfunction (60%), peritonitis (16%), exit site infection (12%), and leakage (6%). Need for access revision increased the risk of peritoneal dialysis technique failure or death (hazard ratio, 1.35; 95% confidence interval, 1

  16. Spontaneity and Equilibrium: Why "?G Equilibrium" Are Incorrect

    Science.gov (United States)

    Raff, Lionel M.

    2014-01-01

    The fundamental criteria for chemical reactions to be spontaneous in a given direction are generally incorrectly stated as ?G chemistry textbooks and even in some more advanced texts. Similarly, the criteria for equilibrium are also misstated as being ?G = 0 or ?A = 0. Following a brief review of the…

  17. Equilibrium problems for Raney densities

    Science.gov (United States)

    Forrester, Peter J.; Liu, Dang-Zheng; Zinn-Justin, Paul

    2015-07-01

    The Raney numbers are a class of combinatorial numbers generalising the Fuss-Catalan numbers. They are indexed by a pair of positive real numbers (p, r) with p > 1 and 0 0 and similarly use both methods to identify the equilibrium problem for (p, r) = (θ/q + 1, 1/q), θ > 0 and q \\in Z+ . The Wiener-Hopf method is used to extend the latter to parameters (p, r) = (θ/q + 1, m + 1/q) for m a non-negative integer, and also to identify the equilibrium problem for a family of densities with moments given by certain binomial coefficients.

  18. Equilibrium in a Production Economy

    Energy Technology Data Exchange (ETDEWEB)

    Chiarolla, Maria B., E-mail: maria.chiarolla@uniroma1.it [Universita di Roma ' La Sapienza' , Dipartimento di Metodi e Modelli per l' Economia, il Territorio e la Finanza, Facolta di Economia (Italy); Haussmann, Ulrich G., E-mail: uhaus@math.ubc.ca [University of British Columbia, Department of Mathematics (Canada)

    2011-06-15

    Consider a closed production-consumption economy with multiple agents and multiple resources. The resources are used to produce the consumption good. The agents derive utility from holding resources as well as consuming the good produced. They aim to maximize their utility while the manager of the production facility aims to maximize profits. With the aid of a representative agent (who has a multivariable utility function) it is shown that an Arrow-Debreu equilibrium exists. In so doing we establish technical results that will be used to solve the stochastic dynamic problem (a case with infinite dimensional commodity space so the General Equilibrium Theory does not apply) elsewhere.

  19. Incentives in Supply Function Equilibrium

    DEFF Research Database (Denmark)

    Vetter, Henrik

    2014-01-01

    The author analyses delegation in homogenous duopoly under the assumption that the firm-managers compete in supply functions. In supply function equilibrium, managers’ decisions are strategic complements. This reverses earlier findings in that the author finds that owners give managers incentives...... to act in an accommodating way. As a result, optimal delegation reduces per-firm output and increases profits to above-Cournot profits. Moreover, in supply function equilibrium the mode of competition is endogenous. This means that the author avoids results that are sensitive with respect to assuming...

  20. Equilibrium in a Production Economy

    International Nuclear Information System (INIS)

    Chiarolla, Maria B.; Haussmann, Ulrich G.

    2011-01-01

    Consider a closed production-consumption economy with multiple agents and multiple resources. The resources are used to produce the consumption good. The agents derive utility from holding resources as well as consuming the good produced. They aim to maximize their utility while the manager of the production facility aims to maximize profits. With the aid of a representative agent (who has a multivariable utility function) it is shown that an Arrow-Debreu equilibrium exists. In so doing we establish technical results that will be used to solve the stochastic dynamic problem (a case with infinite dimensional commodity space so the General Equilibrium Theory does not apply) elsewhere.

  1. The Equilibrium Rule--A Personal Discovery

    Science.gov (United States)

    Hewitt, Paul G.

    2016-01-01

    Examples of equilibrium are evident everywhere and the equilibrium rule provides a reasoned way to view all things, whether in static (balancing rocks, steel beams in building construction) or dynamic (airplanes, bowling balls) equilibrium. Interestingly, the equilibrium rule applies not just to objects at rest but whenever any object or system of…

  2. Non equilibrium atomic processes and plasma spectroscopy

    International Nuclear Information System (INIS)

    Kato, Takako

    2003-01-01

    Along with the technical progress in plasma spectroscopy, non equilibrium ionization processes have been recently observed. We study non local thermodynamic equilibrium and non ionization equilibrium for various kinds of plasmas. Specifically we discuss non equilibrium atomic processes in magnetically confined plasmas, solar flares and laser produced plasmas using a collisional radiative model based on plasma spectroscopic data. (author)

  3. Deviations from thermal equilibrium in plasmas

    International Nuclear Information System (INIS)

    Burm, K.T.A.L.

    2004-01-01

    A plasma system in local thermal equilibrium can usually be described with only two parameters. To describe deviations from equilibrium two extra parameters are needed. However, it will be shown that deviations from temperature equilibrium and deviations from Saha equilibrium depend on one another. As a result, non-equilibrium plasmas can be described with three parameters. This reduction in parameter space will ease the plasma describing effort enormously

  4. Non-equilibrium fluctuation-induced interactions

    International Nuclear Information System (INIS)

    Dean, David S

    2012-01-01

    We discuss non-equilibrium aspects of fluctuation-induced interactions. While the equilibrium behavior of such interactions has been extensively studied and is relatively well understood, the study of these interactions out of equilibrium is relatively new. We discuss recent results on the non-equilibrium behavior of systems whose dynamics is of the dissipative stochastic type and identify a number of outstanding problems concerning non-equilibrium fluctuation-induced interactions.

  5. Simulations of NMR pulse sequences during equilibrium and non-equilibrium chemical exchange

    International Nuclear Information System (INIS)

    Helgstrand, Magnus; Haerd, Torleif; Allard, Peter

    2000-01-01

    The McConnell equations combine the differential equations for a simple two-state chemical exchange process with the Bloch differential equations for a classical description of the behavior of nuclear spins in a magnetic field. This equation system provides a useful starting point for the analysis of slow, intermediate and fast chemical exchange studied using a variety of NMR experiments. The McConnell equations are in the mathematical form of an inhomogeneous system of first-order differential equations. Here we rewrite the McConnell equations in a homogeneous form in order to facilitate fast and simple numerical calculation of the solution to the equation system. The McConnell equations can only treat equilibrium chemical exchange. We therefore also present a homogeneous equation system that can handle both equilibrium and non-equilibrium chemical processes correctly, as long as the kinetics is of first-order. Finally, the same method of rewriting the inhomogeneous form of the McConnell equations into a homogeneous form is applied to a quantum mechanical treatment of a spin system in chemical exchange. In order to illustrate the homogeneous McConnell equations, we have simulated pulse sequences useful for measuring exchange rates in slow, intermediate and fast chemical exchange processes. A stopped-flow NMR experiment was simulated using the equations for non-equilibrium chemical exchange. The quantum mechanical treatment was tested by the simulation of a sensitivity enhanced 15 N-HSQC with pulsed field gradients during slow chemical exchange and by the simulation of the transfer efficiency of a two-dimensional heteronuclear cross-polarization based experiment as a function of both chemical shift difference and exchange rate constants

  6. Understanding Thermal Equilibrium through Activities

    Science.gov (United States)

    Pathare, Shirish; Huli, Saurabhee; Nachane, Madhura; Ladage, Savita; Pradhan, Hemachandra

    2015-01-01

    Thermal equilibrium is a basic concept in thermodynamics. In India, this concept is generally introduced at the first year of undergraduate education in physics and chemistry. In our earlier studies (Pathare and Pradhan 2011 "Proc. episteme-4 Int. Conf. to Review Research on Science Technology and Mathematics Education" pp 169-72) we…

  7. Thermodynamic theory of equilibrium fluctuations

    International Nuclear Information System (INIS)

    Mishin, Y.

    2015-01-01

    The postulational basis of classical thermodynamics has been expanded to incorporate equilibrium fluctuations. The main additional elements of the proposed thermodynamic theory are the concept of quasi-equilibrium states, a definition of non-equilibrium entropy, a fundamental equation of state in the entropy representation, and a fluctuation postulate describing the probability distribution of macroscopic parameters of an isolated system. Although these elements introduce a statistical component that does not exist in classical thermodynamics, the logical structure of the theory is different from that of statistical mechanics and represents an expanded version of thermodynamics. Based on this theory, we present a regular procedure for calculations of equilibrium fluctuations of extensive parameters, intensive parameters and densities in systems with any number of fluctuating parameters. The proposed fluctuation formalism is demonstrated by four applications: (1) derivation of the complete set of fluctuation relations for a simple fluid in three different ensembles; (2) fluctuations in finite-reservoir systems interpolating between the canonical and micro-canonical ensembles; (3) derivation of fluctuation relations for excess properties of grain boundaries in binary solid solutions, and (4) derivation of the grain boundary width distribution for pre-melted grain boundaries in alloys. The last two applications offer an efficient fluctuation-based approach to calculations of interface excess properties and extraction of the disjoining potential in pre-melted grain boundaries. Possible future extensions of the theory are outlined.

  8. Equilibrium theory : A salient approach

    NARCIS (Netherlands)

    Schalk, S.

    1999-01-01

    Whereas the neoclassical models in General Equilibrium Theory focus on the existence of separate commodities, this thesis regards 'bundles of trade' as the unit objects of exchange. Apart from commodities and commodity bundles in the neoclassical sense, the term `bundle of trade' includes, for

  9. Essays in general equilibrium theory

    NARCIS (Netherlands)

    Konovalov, A.

    2001-01-01

    The thesis focuses on various issues of general equilibrium theory and can approximately be divided into three parts. The first part of the thesis studies generalized equilibria in the Arrow-Debreu model in the situation where the strong survival assumption is not satisfied. Chapter four deals with

  10. Financial equilibrium with career concerns

    Directory of Open Access Journals (Sweden)

    Amil Dasgupta

    2006-03-01

    Full Text Available What are the equilibrium features of a financial market where a sizeable proportion of traders face reputational concerns? This question is central to our understanding of financial markets, which are increasingly dominated by institutional investors. We construct a model of delegated portfolio management that captures key features of the US mutual fund industry and embed it in an asset pricing framework. We thus provide a formal model of financial equilibrium with career concerned agents. Fund managers differ in their ability to understand market fundamentals, and in every period investors choose a fund. In equilibrium, the presence of career concerns induces uninformed fund managers to churn, i.e., to engage in trading even when they face a negative expected return. Churners act as noise traders and enhance the level of trading volume. The equilibrium relationship between fund return and net fund flows displays a skewed shape that is consistent with stylized facts. The robustness of our core results is probed from several angles.

  11. Equilibrium with arbitrary market structure

    DEFF Research Database (Denmark)

    Grodal, Birgit; Vind, Karl

    2005-01-01

    . The complete market predicted by this theory is clearly unrealistic, and Radner [10] formulated and proved existence of equilibrium in a multiperiod model with incomplete markets. In this paper the Radner result is extended. Radner assumed a specific structure of markets, independence of preferences...

  12. Nash equilibrium with lower probabilities

    DEFF Research Database (Denmark)

    Groes, Ebbe; Jacobsen, Hans Jørgen; Sloth, Birgitte

    1998-01-01

    We generalize the concept of Nash equilibrium in mixed strategies for strategic form games to allow for ambiguity in the players' expectations. In contrast to other contributions, we model ambiguity by means of so-called lower probability measures or belief functions, which makes it possible...

  13. The perspectives of adults living with peritoneal dialysis: thematic synthesis of qualitative studies.

    Science.gov (United States)

    Tong, Allison; Lesmana, Brian; Johnson, David W; Wong, Germaine; Campbell, Denise; Craig, Jonathan C

    2013-06-01

    Most patients with end-stage renal disease require dialysis to survive because they are unable to access kidney transplantation. Peritoneal dialysis (PD) is recommended by some clinical practice guidelines as the dialysis treatment of choice for adults without significant comorbid conditions or those with residual kidney function. This study aims to synthesize published qualitative studies of patients' experiences, beliefs, and attitudes about PD. We conducted a systematic review and thematic synthesis of qualitative studies of adult perspectives of living with PD. Databases (MEDLINE, Embase, PsycINFO, and CINAHL), theses, and reference lists were searched to November 2011. 39 studies involving 387 participants were included. We identified 7 themes: resilience and confidence (determination and overcoming vicissitudes), support structures (strong family relationship, peer support, professional dedication, social abandonment, and desire for holistic care), overwhelming responsibility (disruptive intrusion, family burden, and onerous treatment regimen), control (gaining bodily awareness, achieving independence and self-efficacy, and information seeking), freedom (flexibility and autonomy, retaining social functioning, and ability to travel), sick identity (damage to self-esteem and invisible suffering), and disablement (physical incapacitation and social loss and devaluation). PD can offer patients a sense of control, independence, self-efficacy, and freedom. However, holistic and multidisciplinary care is needed to mitigate the risks of impaired self-esteem, physical incapacitation, reduced social functioning, and poor sense of self-worth. Strategies that aim to strengthen social support and promote resilience and confidence in patients are integral to achieving positive adjustment, improved psychosocial outcomes, and treatment satisfaction. Copyright © 2013 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  14. Vitamin K antagonist use and mortality in dialysis patients

    NARCIS (Netherlands)

    Voskamp, Pauline W.M.; Rookmaaker, Maarten B.; Verhaar, Marianne C.; Dekker, Friedo W.; Ocak, Gurbey

    2018-01-01

    Background. The risk-benefit ratio of vitamin K antagonists for different CHA2DS2-VASc scores in patients with end-stage renal disease treated with dialysis is unknown. The aim of this study was to investigate the association between vitamin K antagonist use and mortality for different CHA2DS2-VASc

  15. High fall incidence and fracture rate in elderly dialysis patients

    NARCIS (Netherlands)

    Polinder-Bos, H. A.; Emmelot-Vonk, M. H.; Gansevoort, R. T.; Diepenbroek, A.; Gaillard, C. A. J. M.

    2014-01-01

    Background: Although it is recognised that the dialysis population is ageing rapidly, geriatric complications such as falls are poorly appreciated, despite the many risk factors for falls in this population. The objective of this study was to determine the incidence, complications and risk factors

  16. Detection of microorganisms, endotoxins and aluminum in mobile dialysis services

    Directory of Open Access Journals (Sweden)

    Priscila Rodrigues de Jesus

    2017-11-01

    Full Text Available Hemodialysis water and dialysates are fundamental in the treatment of kidney disease. During just one hemodialysis session, 120 liters of dialysate are consumed. Thus, it is essential that the parameters of chemical and microbiological quality of the fluids used in dialysis systems are carefully observed. In this study, water samples were collected at 12 hospitals in the state of Rio de Janeiro. The samples were obtained at three points of fluid reservoirs: pre-, post-osmosis and dialysis solution. After collection, colony forming units (CFU, total coliforms and Escherichia coli 100 mL-1 were quantified. Later, isolated colonies and endotoxin content were identified by biochemical assays. Data about total aluminum levels per sample (mg L-1 were also obtained. Samples of all mobile dialysis services and points of collection were contaminated above the levels set out by national laws, in particular by Pseudomonas aeruginosa. Endotoxin levels were also above the recommended by current legislation (> 0.25 EU mL-1. Only three samples contained detectable levels of aluminum, which were found to be above the recommended values for the corresponding resolution (0.01 mg L-1. Finally, there were no observable amounts of total coliforms and E. coli 100 mL-1 sample. The data from this study are an important step forward in the standardization and control of chemical/microbiological quality of mobile dialysis services.

  17. Benfotiamine protects against peritoneal and kidney damage in peritoneal dialysis.

    Science.gov (United States)

    Kihm, Lars P; Müller-Krebs, Sandra; Klein, Julia; Ehrlich, Gregory; Mertes, Laura; Gross, Marie-Luise; Adaikalakoteswari, Antonysunil; Thornalley, Paul J; Hammes, Hans-Peter; Nawroth, Peter P; Zeier, Martin; Schwenger, Vedat

    2011-05-01

    Residual renal function and the integrity of the peritoneal membrane contribute to morbidity and mortality among patients treated with peritoneal dialysis. Glucose and its degradation products likely contribute to the deterioration of the remnant kidney and damage to the peritoneum. Benfotiamine decreases glucose-induced tissue damage, suggesting the potential for benefit in peritoneal dialysis. Here, in a model of peritoneal dialysis in uremic rats, treatment with benfotiamine decreased peritoneal fibrosis, markers of inflammation, and neovascularization, resulting in improved characteristics of peritoneal transport. Furthermore, rats treated with benfotiamine exhibited lower expression of advanced glycation endproducts and their receptor in the peritoneum and the kidney, reduced glomerular and tubulointerstitial damage, and less albuminuria. Increased activity of transketolase in tissue and blood contributed to the protective effects of benfotiamine. In primary human peritoneal mesothelial cells, the addition of benfotiamine led to enhanced transketolase activity and decreased expression of advanced glycation endproducts and their receptor. Taken together, these data suggest that benfotiamine protects the peritoneal membrane and remnant kidney in a rat model of peritoneal dialysis and uremia. Copyright © 2011 by the American Society of Nephrology

  18. [Optimal use of peritoneal dialysis with multi-disciplinary management].

    Science.gov (United States)

    Elios Russo, Gaspare; Martinez, A; Mazzaferro, S; Nunzi, A; Testorio, M; Rocca, A R; Lai, S; Morgia, A; Borzacca, B; Gnerre Musto, T

    2013-01-01

    Considering the increasing incidence of chronic kidney disease and the increased use of peritoneal dialysis, we wanted to assess whether the multidisciplinary management of patients in peritoneal dialysis might produce improvement in the quality of patients' lives when compared to management by a routine team of operators. Our study observed 40 patients on peritoneal dialysis in our Department between 2010 and 2012. They were randomly assigned to either group A, the routine team which consisted of a nephrologist and a nurse, or group B, a multidisciplinary team comprising several medical specialists, a nurse, a psychologist and a social worker. Two tests, KDQOL-SF and MMPI-2, were administered to both groups. In group B, the number of days of hospitalization and day hospital were more than 88% lower when compared to group A. The multidisciplinary team achieved better results with the KDQOL-SF test with regards to both emotional and objective dimensions. The Pearson coefficient between the results of the two questionnaires shows how multidisciplinary management can positively influence the perceived well-being of the patient and his or her adherence to treatment. In a multidisciplinary team, each operator, in addition to his or her specific role, also contributes to the achievement of the overall objective, namely of ensuring an optimal quality of life to the patient on peritoneal dialysis thereby allowing these patients to continue their professional and social lives.

  19. Relative survival of peritoneal dialysis and haemodialysis patients

    DEFF Research Database (Denmark)

    Heaf, James G; Wehberg, Sonja

    2014-01-01

    INTRODUCTION: Epidemiological studies consistently show an initial survival advantage for PD patients compared to HD. It has recently been suggested that this is due to the fact that many HD patients are referred late, and start dialysis on an acute, in-patient basis. The present study was perfor...

  20. Capnocytophaga cynodegmi peritonitis in a peritoneal dialysis patient

    DEFF Research Database (Denmark)

    Pers, Charlotte; Tvedegaard, Erling; Christensen, Jens Jørgen

    2007-01-01

    The first reported case of peritonitis caused by Capnocytophaga cynodegmi is presented. The patient was treated with peritoneal dialysis and had contact with a cat. C. cynodegmi is part of the normal oral flora of dogs and cats but is very rarely isolated in clinical specimens from humans....

  1. Peritoneal Dialysis-Related Peritonitis: Atypical and Resistant Organisms

    NARCIS (Netherlands)

    Cho, Yeoungjee; Struijk, Dirk Gijsbert

    2017-01-01

    Peritoneal dialysis (PD)-related peritonitis remains to be one of the most frequent and serious complications of PD. In this study, existing literature has been reviewed on PD peritonitis caused by atypical organisms and antibiotic resistant organisms and their impact on patient outcomes. Although

  2. Quantification of free water transport in peritoneal dialysis

    NARCIS (Netherlands)

    Smit, Watske; Struijk, Dirk G.; Ho-Dac-Pannekeet, Marja M.; Krediet, Raymond T.

    2004-01-01

    BACKGROUND: In peritoneal dialysis (PD) total net ultrafiltration (NUF) is dependent on transport through small pores and through water channels in the peritoneum. These channels are impermeable to solutes, and therefore, crystalloid osmotic-induced free water transport occurs through them. Several

  3. Advances in peritoneal dialysis: towards improved efficacy and safety

    NARCIS (Netherlands)

    Krediet, R. T.

    1998-01-01

    BACKGROUND: The success of peritoneal dialysis on the short-term is mainly dependent on the prevention of infectious and technical complications. The mid-term results will to a large extent be determined by the ability to remove enough uraemic toxins to prevent uraemic complications and

  4. [Technological advances and micro-inflammation in dialysis patients].

    Science.gov (United States)

    Ferro, Giuseppe; Ravaglia, Fiammetta; Ferrari, Elisa; Romoli, Elena; Michelassi, Stefano; Caiani, David; Pizzarelli, Francesco

    2015-01-01

    As currently performed, on line hemodiafiltration reduces, but does not normalize, the micro-inflammation of uremic patients. Recent technological advances make it possible to further reduce the inflammation connected to the dialysis treatment. 
Short bacterial DNA fragments are pro-inflammatory and can be detected in the dialysis fluids. However, their determination is not currently within normal controls of the quality of the dialysate. The scenario may change once the analysis of these fragments yields reliable, inexpensive, quick and easy to evaluate the results. At variance with standard bicarbonate dialysate, Citrate dialysate induces far less inflammation both for the well-known anti-inflammatory effect of such buffer and also because it is completely acetate free, e.g. a definitely pro-inflammatory buffer. However, the extensive use of citrate dialysate in chronic dialysis is prevented because of concerns about its potential calcium lowering effect. In our view, high convective exchange on line hemodiafiltration performed with dialysate, whose sterility and a-pirogenicity is guaranteed by increasingly sophisticated controls and with citrate buffer whose safety is certified, can serve as the gold standard of dialysis treatments in future.

  5. Electronic states and nature of bonding of the molecule NiGe by all electron ab initio Hartree–Fock (HF) and configuration interaction (CI) calculations and mass spectrometric equilibrium experiments

    DEFF Research Database (Denmark)

    Shim, Irene; Kingcade, Joseph E.; Gingerich, Karl A.

    1988-01-01

    -lying electronic states of the NiGe molecule have all been characterized by the symmetry of the hole in the 3d shell of Ni. The dissociation energy of the NiGe molecule has been determined from our high temperature mass spectrometric equilibrium data in combination with the theoretical results as D [open circle] 0...... =286.8±10.9 kJ mol−1. The standard heat of formation of the NiGe molecule has been obtained as DeltaH [open circle] f,298 =514±12 kJ mol−1. The Journal of Chemical Physics is copyrighted by The American Institute of Physics....

  6. [Automatic system control and its application in dialysis].

    Science.gov (United States)

    Santoro, A; Mancini, E; Ferramosca, E

    2007-01-01

    The progressive increase in the mean age of dialysis patients associated with increasing comorbidity factors such as the presence of cardiovascular disease and diabetes have significantly worsened patients' clinical status and tolerance to hemodialysis. On the other hand, the demand for short treatment times increases the risk of hemodynamic instability as well as inadequate depuration. The traditional management of the dialysis session by setting predefined treatment parameters and carrying out active therapeutic intervention only in the event of complications is definitely unsuitable for short-lasting treatments, which are often complicated by hemodynamic instability, especially in critically ill patients. The first step in improving the management of the dialysis session is the use of uninvasive systems for continuous monitoring of the hemodynamic and biochemical parameters that characterize dialysis quality. In the last decade, special sensors have been designed for continuous measurement of blood volume, blood temperature, blood pressure, heart rate and electrolytes. As a second step, some of these devices have been interfaced with the dialysis equipment, mainly with a view to preventing cardiocirculatory instability but also monitoring the efficiency of dialysis (biofeedback control systems). The basic components of a biofeedback system are the plant, the sensors, the actuators, and the controller. The plant is the biological process we need to control, while the sensors are the devices used for measuring the output variables. The actuators are the working arms of the controller. The controller is the mathematical model that continuously sets the measured output variable against the reference input and modifies the actuators in order to reduce any discrepancies. In actual practice, however, there are a number of conceptual, physical and technological difficulties to overcome. In particular, the behavior of what is to be controlled may be nonlinear and time

  7. Multicentre study of treatment outcomes in Australian adolescents and young adults commencing dialysis.

    Science.gov (United States)

    Krischock, Leah; Kennedy, Sean E; Hayen, Andrew

    2017-12-01

    The aim of the study is to improve the understanding of outcomes and complications of dialysis in adolescents and young adults (AYA) to inform decisions about dialysis modality in this patient population. Registry data on Australian AYA aged 13 to 20 years who commenced dialysis between 1/1/2000 and 31/12/2013 were retrieved from the Australia and New Zealand Dialysis and Transplantation Registry and analyzed to determine associations between demographic characteristics, dialysis modality and outcomes. During the study period 300 AYA commenced dialysis at a median age of 17.2 years (IQR 15.6 to 18.6 years). Haemodialysis (HD) was the initial dialysis modality in 201 patients (67%). No significant differences between AYA receiving HD and peritoneal dialysis (PD) were noted in patient gender, age, race, primary renal disease, treating centre type, remoteness of residential area, lateness of referral or period of study. Mean haemoglobin levels were lower in the HD group (P = 0.005) and significantly fewer HD patients attended school full time compared to patients managed on PD (P = 0.002 first year; P = 0.05 second year). Dialysis modality choice does not appear to be influenced by patient characteristics nor dialysis outcomes. Future research is required to examine the reasons that HD is preferred over PD and to determine the optimal method of dialysis for this age group. © 2016 Asian Pacific Society of Nephrology.

  8. On generalized operator quasi-equilibrium problems

    Science.gov (United States)

    Kum, Sangho; Kim, Won Kyu

    2008-09-01

    In this paper, we will introduce the generalized operator equilibrium problem and generalized operator quasi-equilibrium problem which generalize the operator equilibrium problem due to Kazmi and Raouf [K.R. Kazmi, A. Raouf, A class of operator equilibrium problems, J. Math. Anal. Appl. 308 (2005) 554-564] into multi-valued and quasi-equilibrium problems. Using a Fan-Browder type fixed point theorem in [S. Park, Foundations of the KKM theory via coincidences of composites of upper semicontinuous maps, J. Korean Math. Soc. 31 (1994) 493-519] and an existence theorem of equilibrium for 1-person game in [X.-P. Ding, W.K. Kim, K.-K. Tan, Equilibria of non-compact generalized games with L*-majorized preferences, J. Math. Anal. Appl. 164 (1992) 508-517] as basic tools, we prove new existence theorems on generalized operator equilibrium problem and generalized operator quasi-equilibrium problem which includes operator equilibrium problems.

  9. Vasoactive Peptide Levels after Change of Dialysis Mode

    Directory of Open Access Journals (Sweden)

    Fredrik Uhlin

    2015-10-01

    Full Text Available Background/Aims: Plasma concentrations of the N-terminal fragment of pro-brain natriuretic peptide (NT-proBNP are increased in end-stage renal disease. Improvement in hemodynamic stability has been reported when switching from hemodialysis (HD to on-line hemodiafiltration (ol-HDF. The aim of this study was to investigate plasma concentrations of NT-proBNP, BNP and neuropeptide Y (NPY during a 1-year follow-up, after a change from high-flux HD to postdilution ol-HDF. Additional variables were also studied, e.g. pulse wave velocity and ordinary clinical parameters. Method: We conducted a prospective, single-center study including 35 patients who were switched from HD to HDF. Plasma concentrations of NT-proBNP, BNP and NPY before and after dialysis were measured at baseline (i.e. HD and at 1, 2, 4, 6 and 12 months on HDF. Results: All three peptide levels decreased significantly during HD and HDF when comparing concentrations before and after dialysis. Mean absolute value (before/after and relative decrease (% before versus after dialysis was 13.697/9.497 ng/l (31% for NT-proBNP, 62/40 ng/ml (35% for BNP and 664/364 pg/l (45% for NPY. No significant differences were observed when comparing predialysis values over time. However, postdialysis NT-proBNP concentration showed a significant decrease of 48% over time after the switch to HDF. Conclusion: The postdialysis plasma levels of NT-proBNP, BNP and NPY decreased significantly during both dialysis modes when compared to before dialysis. The postdialysis lowering of NT-proBNP increased further over time after the switch to ol-HDF; the predialysis levels were unchanged, suggesting no effect on its production in the ventricles of the heart.

  10. Depression in hemodialysis patients: the role of dialysis shift

    Directory of Open Access Journals (Sweden)

    Flavio Teles

    2014-03-01

    Full Text Available OBJECTIVE: Depression is the most important neuropsychiatric complication in chronic kidney disease because it reduces quality of life and increases mortality. Evidence demonstrating the association between dialysis shift and depression is lacking; thus, obtaining such evidence was the main objective of this study. METHOD: This cross-sectional study included patients attending a hemodialysis program. Depression was diagnosed using Beck's Depression Inventory. Excessive daytime sleepiness was evaluated using the Epworth Sleepiness Scale. RESULTS: A total of 96 patients were enrolled (55 males, age 48±14 years. Depression and excessive daytime sleepiness were observed in 42.7% and 49% of the patients, respectively. When comparing variables among the three dialysis shifts, there were no differences in age, dialysis vintage, employment status, excessive daytime sleepiness, hemoglobin, phosphorus levels, or albumin levels. Patients in the morning shift were more likely to live in rural areas (p<0.0001, although patients in rural areas did not have a higher prevalence of depression (p= 0.30. Patients with depression were more likely to be dialyzed during the morning shift (p= 0.008. Independent risk factors for depression were age (p<0.03, lower levels of hemoglobin (p<0.01 and phosphorus (p<0.01, and dialysis during the morning shift (p= 0.0009. The hospitalization risk of depressive patients was 4.5 times higher than that of nondepressive patients (p<0.008. CONCLUSION: These data suggest that depression is associated with dialysis shift, higher levels of phosphorus, and lower levels of hemoglobin. The results highlight the need for randomized trials to determine whether this association occurs by chance or whether circadian rhythm disorders may play a role.

  11. Rationale for a home dialysis virtual ward: design and implementation.

    Science.gov (United States)

    Schachter, Michael E; Bargman, Joanne M; Copland, Michael; Hladunewich, Michelle; Tennankore, Karthik K; Levin, Adeera; Oliver, Matthew; Pauly, Robert P; Perl, Jeffrey; Zimmerman, Deborah; Chan, Christopher T

    2014-02-14

    Home-based renal replacement therapy (RRT) [peritoneal dialysis (PD) and home hemodialysis (HHD)] offers independent quality of life and clinical advantages compared to conventional in-center hemodialysis. However, follow-up may be less complete for home dialysis patients following a change in care settings such as post hospitalization. We aim to implement a Home Dialysis Virtual Ward (HDVW) strategy, which is targeted to minimize gaps of care. The HDVW Pilot Study will enroll consecutive PD and HHD patients who fulfilled any one of our inclusion criteria: 1. following discharge from hospital, 2. after interventional procedure(s), 3. prescription of anti-microbial agents, or 4. following completion of home dialysis training. Clinician-led telephone interviews are performed weekly for 2 weeks until VW discharge. Case-mix (modified Charlson Comorbidity Index), symptoms (the modified Edmonton Symptom Assessment Scale) and patient satisfaction are assessed serially. The number of VW interventions relating to eight pre-specified domains will be measured. Adverse events such as re-hospitalization and health-services utilization will be ascertained through telephone follow-up after discharge from the VW at 2, 4, 12 weeks. The VW re-hospitalization rate will be compared with a contemporary cohort (matched for age, gender, renal replacement therapy and co-morbidities). Our protocol has been approved by research ethics board (UHN: 12-5397-AE). Written informed consent for participation in the study will be obtained from participants. This report serves as a blueprint for the design and implementation of a novel health service delivery model for home dialysis patients. The major goal of the HDVW initiative is to provide appropriate and effective supports to medically complex patients in a targeted window of vulnerability. (NCT01912001).

  12. BODY COMPOSITION IN HEMODIALYSIS AND PERITONEAL DIALYSIS PATIENTS

    Directory of Open Access Journals (Sweden)

    Nam Ho Kim

    2012-06-01

    Full Text Available Bioimpedance analysis is a reliable technique for determining post dialysis target weight. Using this technique, we can understand body fluid status easier and conveniently. Moreover this technique can be used for check nutrition status and nutritional status of dialysis patients. We compared the body fluid status and nutrition status between hemodialysis (HD patients and peritoneal dialysis (PD patients by BCM (Body composition monitor technique. We studied 48 (30 males and 18 females PD patients, 21 (10 males and 11 females HD patients. Body composition monitoring (BCM, Fesenitus Medical Care, Germany was used as a tool for the analysis of bioimpedance. Extracellular water, Total body water, Intracellular water, Overhydration, E/I, Lean tissue mass, Fat Tissue mass was measured and those results were compared between two groups. HD patients were more hydrated than PD patients (61.9% vs. 35.4% and nutritional status such as LTI was poorer than peritoneal dialysis patients (11.7±1.7 vs. 15.3±2.6. Although total body water is more abundant in peritoneal patients (29.4±5.5L vs. 35.9±6.2L, Extracellular water and intracellular water ratio was relatively higher in Hemodialysis patients (E/I 0.98±0.13 vs. 0.87±0.12. The nutrition status was better in PD patients by comparing the percent of lean tissue mass (LTM% between two groups (LTM% 52.1±10.6% vs. 66.8±11.3. In conclusions, Hemodialysis patients were more hydrated with poorer nutrition status than peritoneal dialysis patients, but, due to the significant difference of age between two groups, further study should be required.

  13. Profile of peginesatide and its potential for the treatment of anemia in adults with chronic kidney disease who are on dialysis

    Directory of Open Access Journals (Sweden)

    Mikhail A

    2012-05-01

    Full Text Available Ashraf MikhailRenal Unit, Morriston Hospital, Swansea University, Wales, UKAbstract: Peginesatide is a synthetic, dimeric peptide that is covalently linked to polyethylene glycol (PEG. The amino acid sequence of peginesatide is unrelated to that of erythropoietin (EPO and is not immunologically cross-reactive with EPO. Peginesatide binds to and activates the human EPO receptor, stimulating the proliferation and differentiation of human red cell precursors in vitro in a manner similar to other EPO-stimulating agents (ESAs. In Phase II and III studies in dialysis and predialysis patients, peginesatide administered once monthly was as effective as epoetin alfa given thrice weekly (dialysis patients or darbepoetin given once weekly (nondialysis patients, in correcting anemia of chronic kidney disease as well as maintaining hemoglobin within the desired target range. In the dialysis population, the reported side-effect profile of peginesatide was comparable to that known with other marketed ESAs. In the nondialysis studies, compared with those treated with darbepoetin, patients treated with peginesatide experienced a higher adverse-effect profile. Peginesatide is likely to be licensed for treatment of renal anemia in dialysis patients and not in nondialysis patients. Despite this limitation, peginesatide is likely to prove valuable in treating dialysis patients because of its infrequent mode of administration, thereby allowing for a reduced number of injections, with associated better compliance, reduced cold storage requirement, and improved stock accountability. PEGylated therapeutic proteins can elicit immunological response to the PEG moiety of the therapeutic complex. Only long-term experience and post-marketing surveillance will address whether this immunological response will have any impact on the clinical efficacy or safety of peginesatide in clinical practice.Keywords: peginesatide, dialysis, chronic kidney disease

  14. Standard on microbiological management of fluids for hemodialysis and related therapies by the Japanese Society for Dialysis Therapy 2008.

    Science.gov (United States)

    Kawanishi, Hideki; Akiba, Takashi; Masakane, Ikuto; Tomo, Tadashi; Mineshima, Michio; Kawasaki, Tadayuki; Hirakata, Hideki; Akizawa, Tadao

    2009-04-01

    The Committee of Scientific Academy of the Japanese Society for Dialysis Therapy (JSDT) proposes a new standard on microbiological management of fluids for hemodialysis and related therapies. This standard is within the scope of the International Organization for Standardization (ISO), which is currently under revision. This standard is to be applied to the central dialysis fluid delivery systems (CDDS), which are widely used in Japan. In this standard, microbiological qualities for dialysis water and dialysis fluids are clearly defined by endotoxin level and bacterial count. The qualities of dialysis fluids were classified into three levels: standard, ultrapure, and online prepared substitution fluid. In addition, the therapeutic application of each dialysis fluid is clarified. Since high-performance dialyzers are frequently used in Japan, the standard recommends that ultrapure dialysis fluid be used for all dialysis modalities at all dialysis facilities. It also recommends that the dialysis equipment safety management committee at each facility should validate the microbiological qualities of online prepared substitution fluid.

  15. Using nonequilibrium capillary electrophoresis of equilibrium mixtures (NECEEM) for simultaneous determination of concentration and equilibrium constant.

    Science.gov (United States)

    Kanoatov, Mirzo; Galievsky, Victor A; Krylova, Svetlana M; Cherney, Leonid T; Jankowski, Hanna K; Krylov, Sergey N

    2015-03-03

    Nonequilibrium capillary electrophoresis of equilibrium mixtures (NECEEM) is a versatile tool for studying affinity binding. Here we describe a NECEEM-based approach for simultaneous determination of both the equilibrium constant, K(d), and the unknown concentration of a binder that we call a target, T. In essence, NECEEM is used to measure the unbound equilibrium fraction, R, for the binder with a known concentration that we call a ligand, L. The first set of experiments is performed at varying concentrations of T, prepared by serial dilution of the stock solution, but at a constant concentration of L, which is as low as its reliable quantitation allows. The value of R is plotted as a function of the dilution coefficient, and dilution corresponding to R = 0.5 is determined. This dilution of T is used in the second set of experiments in which the concentration of T is fixed but the concentration of L is varied. The experimental dependence of R on the concentration of L is fitted with a function describing their theoretical dependence. Both K(d) and the concentration of T are used as fitting parameters, and their sought values are determined as the ones that generate the best fit. We have fully validated this approach in silico by using computer-simulated NECEEM electropherograms and then applied it to experimental determination of the unknown concentration of MutS protein and K(d) of its interactions with a DNA aptamer. The general approach described here is applicable not only to NECEEM but also to any other method that can determine a fraction of unbound molecules at equilibrium.

  16. Measured glomerular filtration rate at dialysis initiation and clinical outcomes of Indian peritoneal dialysis patients

    Directory of Open Access Journals (Sweden)

    N Prasad

    2017-01-01

    Full Text Available The optimal time for dialysis initiation remains controversial. Studies have failed to show better outcomes with early initiation of hemodialysis; even a few had shown increased adverse outcomes including poorer survival. Few studies have examined the same in patients on peritoneal dialysis (PD. Measured glomerular filtration rate (mGFR not creatinine-based estimated GFR is recommended as the measure of kidney function in end-stage renal disease (ESRD patients. The objective of this observational study was to compare the outcomes of Indian patients initiated on PD with different residual renal function (RRF as measured by 24-h urinary clearance method. A total of 352 incident patients starting on chronic ambulatory PD as the first modality of renal replacement therapy were followed prospectively. Patients were categorized into three groups as per mGFR at the initiation of PD (≤5, >5–10, and> 10 ml/min/1.73 m2. Patient survival and technique survival were compared among the three groups. Patients with GFR of ≤5 ml/min/1.73 m2 (hazard ratio [HR] - 3.42, 95% confidence interval [CI] - 1.85–6.30, P = 0.000 and> 5–10 ml/min/1.73 m2 (HR - 2.16, 95% CI - 1.26–3.71, P = 0.005 had higher risk of mortality as compared to those with GFR of> 10 ml/min/1.73 m2. Each increment of 1 ml/min/1.73 m2 in baseline GFR was associated with 10% reduced risk of death (HR - 0.90, 95% CI - 0.85–0.96, P = 0.002. Technique survival was poor in those with an initial mGFR of ≤5 ml/min/1.73 m2 as compared to other categories. RRF at the initiation was also an important factor predicting nutritional status at 1 year of follow-up. To conclude, initiation of PD at a lower baseline mGFR is associated with poorer patient and technique survival in Indian ESRD patients.

  17. Is Peritonitis Risk Increased in Elderly Patients on Peritoneal Dialysis? Report from the French Language Peritoneal Dialysis Registry (RDPLF).

    Science.gov (United States)

    Duquennoy, Simon; Béchade, Clémence; Verger, Christian; Ficheux, Maxence; Ryckelynck, Jean-Philippe; Lobbedez, Thierry

    2016-01-01

    ♦ This study was carried out to examine whether or not elderly patients on peritoneal dialysis (PD) had an increased risk of peritonitis. ♦ This was a retrospective cohort study based on data from the French Language Peritoneal Dialysis Registry. We analyzed 8,396 incident patients starting PD between January 2003 and December 2010. The end of the observation period was 31 December 2012. Patients were separated into 2 age groups: up to 75 and over of 75 years old. ♦ Among 8,396 patients starting dialysis there were 3,173 patients older than 75. When using a Cox model, no association was found between age greater than 75 years and increased risk of peritonitis (hazard ratio [HR]: 0.97 [0.88 - 1.07]). Diabetes (HR: 1.14 [1.01 - 1.28] and continuous ambulatory PD (HR: 1.13 [1.04 - 1.23]) were significantly associated with a higher risk of peritoneal infection whereas nurse-assisted PD was associated with a lower risk of peritonitis (HR: 0.85 [0.78 - 0.94]. In the analysis restricted to the 3,840 self-care PD patients, there was no association between age older than 75 years and risk of peritonitis. ♦ The risk of peritonitis is not increased in elderly patients on PD in a country where assisted PD is available. Copyright © 2016 International Society for Peritoneal Dialysis.

  18. Equilibrium studies of helical axis stellarators

    International Nuclear Information System (INIS)

    Hender, T.C.; Carreras, B.A.; Garcia, L.; Harris, J.H.; Rome, J.A.; Cantrell, J.L.; Lynch, V.E.

    1984-01-01

    The equilibrium properties of helical axis stellarators are studied with a 3-D equilibrium code and with an average method (2-D). The helical axis ATF is shown to have a toroidally dominated equilibrium shift and good equilibria up to at least 10% peak beta. Low aspect ratio heliacs, with relatively large toroidal shifts, are shown to have low equilibrium beta limits (approx. 5%). Increasing the aspect ratio and number of field periods proportionally is found to improve the equilibrium beta limit. Alternatively, increasing the number of field periods at fixed aspect ratio which raises and lowers the toroidal shift improves the equilibrium beta limit

  19. Non-equilibrium phase transitions in complex plasma

    International Nuclear Information System (INIS)

    Suetterlin, K R; Raeth, C; Ivlev, A V; Thomas, H M; Khrapak, S; Zhdanov, S; Rubin-Zuzic, M; Morfill, G E; Wysocki, A; Loewen, H; Goedheer, W J; Fortov, V E; Lipaev, A M; Molotkov, V I; Petrov, O F

    2010-01-01

    Complex plasma being the 'plasma state of soft matter' is especially suitable for investigations of non-equilibrium phase transitions. Non-equilibrium phase transitions can manifest in dissipative structures or self-organization. Two specific examples are lane formation and phase separation. Using the permanent microgravity laboratory PK-3 Plus, operating onboard the International Space Station, we performed unique experiments with binary mixtures of complex plasmas that showed both lane formation and phase separation. These observations have been augmented by comprehensive numerical and theoretical studies. In this paper we present an overview of our most important results. In addition we put our results in context with research of complex plasmas, binary systems and non-equilibrium phase transitions. Necessary and promising future complex plasma experiments on phase separation and lane formation are briefly discussed.

  20. Factors influencing access to education, decision making, and receipt of preferred dialysis modality in unplanned dialysis start patients.

    Science.gov (United States)

    Machowska, Anna; Alscher, Mark Dominik; Reddy Vanga, Satyanarayana; Koch, Michael; Aarup, Michael; Qureshi, Abdul Rashid; Lindholm, Bengt; Rutherford, Peter A

    2016-01-01

    Unplanned dialysis start (UPS) leads to worse clinical outcomes than planned start, and only a minority of patients ever receive education on this topic and are able to make a modality choice, particularly for home dialysis. This study aimed to determine the predictive factors for patients receiving education, making a decision, and receiving their preferred modality choice in UPS patients following a UPS educational program (UPS-EP). The Offering Patients Therapy Options in Unplanned Start (OPTiONS) study examined the impact of the implementation of a specific UPS-EP, including decision support tools and pathway improvement on dialysis modality choice. Linear regression models were used to examine the factors predicting three key steps: referral and receipt of UPS-EP, modality decision making, and actual delivery of preferred modality choice. A simple economic assessment was performed to examine the potential benefit of implementing UPS-EP in terms of dialysis costs. The majority of UPS patients could receive UPS-EP (214/270 patients) and were able to make a decision (177/214), although not all patients received their preferred choice (159/177). Regression analysis demonstrated that the initial dialysis modality was a predictive factor for referral and receipt of UPS-EP and modality decision making. In contrast, age was a predictor for referral and receipt of UPS-EP only, and comorbidity was not a predictor for any step, except for myocardial infarction, which was a weak predictor for lower likelihood of receiving preferred modality. Country practices predicted UPS-EP receipt and decision making. Economic analysis demonstrated the potential benefit of UPS-EP implementation because dialysis modality costs were associated with modality distribution driven by patient preference. Education and decision support can allow UPS patients to understand their options and choose dialysis modality, and attention needs to be focused on ensuring equity of access to educational

  1. Students’ misconceptions on solubility equilibrium

    Science.gov (United States)

    Setiowati, H.; Utomo, S. B.; Ashadi

    2018-05-01

    This study investigated the students’ misconceptions of the solubility equilibrium. The participants of the study consisted of 164 students who were in the science class of second year high school. Instrument used is two-tier diagnostic test consisting of 15 items. Responses were marked and coded into four categories: understanding, misconception, understand little without misconception, and not understanding. Semi-structured interviews were carried out with 45 students according to their written responses which reflected different perspectives, to obtain a more elaborated source of data. Data collected from multiple methods were analyzed qualitatively and quantitatively. Based on the data analysis showed that the students misconceptions in all areas in solubility equilibrium. They had more misconceptions such as in the relation of solubility and solubility product, common-ion effect and pH in solubility, and precipitation concept.

  2. An introduction to equilibrium thermodynamics

    CERN Document Server

    Morrill, Bernard; Hartnett, James P; Hughes, William F

    1973-01-01

    An Introduction to Equilibrium Thermodynamics discusses classical thermodynamics and irreversible thermodynamics. It introduces the laws of thermodynamics and the connection between statistical concepts and observable macroscopic properties of a thermodynamic system. Chapter 1 discusses the first law of thermodynamics while Chapters 2 through 4 deal with statistical concepts. The succeeding chapters describe the link between entropy and the reversible heat process concept of entropy; the second law of thermodynamics; Legendre transformations and Jacobian algebra. Finally, Chapter 10 provides a

  3. Money Inventories in Search Equilibrium

    OpenAIRE

    Berentsen, Aleksander

    1998-01-01

    The paper relaxes the one unit storage capacity imposed in the basic search-theoretic model of fiat money with indivisible real commodities and indivisible money. Agents can accumulate as much money as they want. It characterizes the stationary distributions of money and shows that for reasonable parameter values (e.g. production cost, discounting, degree of specialization) a monetary equilibrium exists. There are multiple stationary distributions of a given amount of money, which differ in t...

  4. Physical phenomena in a low-temperature non-equilibrium plasma and in MHD generators with non-equilibrium conductivity

    International Nuclear Information System (INIS)

    Velikhov, E.P.; Golubev, V.S.; Dykhne, A.M.

    1976-01-01

    The paper assesses the position in 1975 of theoretical and experimental work on the physics of a magnetohydrodynamic generator with non-equilibrium plasma conductivity. This research started at the beginning of the 1960s; as work on the properties of thermally non-equilibrium plasma in magnetic fields and also in MHD generator ducts progressed, a number of phenomena were discovered and investigated that had either been unknown in plasma physics or had remained uninvestigated until that time: ionization instability and ionization turbulence of plasma in a magnetic field, acoustic instability of a plasma with anisotropic conductivity, the non-equilibrium ionization wave and the energy balance of a non-equilibrium plasma. At the same time, it was discovered what physical requirements an MHD generator with non-equilibrium conductivity must satisfy to achieve high efficiency in converting the thermal or kinetic energy of the gas flow into electric energy. The experiments on MHD power generation with thermally non-equilibrium plasma carried out up to 1975 indicated that it should be possible to achieve conversion efficiencies of up to 20-30%. (author)

  5. APPETITE PREDICTS INTAKE AND NUTRITIONAL STATUS IN PATIENTS RECEIVING PERITONEAL DIALYSIS.

    Science.gov (United States)

    Young, Valerie; Balaam, Sarah; Orazio, Linda; Bates, Annerley; Badve, Sunil V; Johnson, David W; Campbell, Katrina L

    2016-06-01

    Sub-optimal nutrition status is common amongst patients receiving peritoneal dialysis (PD) and leads to poor clinical outcome. This population experiences multi-factorial challenges to achieving optimal nutritional status, particularly driven by inadequate intake. The aim of this investigation was to identify factors associated with inadequate protein intake and sub-optimal nutritional status in patients undergoing PD. This was a cross-sectional study of 67 adult patients receiving PD (mean age 59 ± 14 years; 57% male) within a single centre. Participants were consecutively recruited and interviewed by renal dietitians, collecting: Subjective Global Assessment (SGA); quality of life (using EQ-5D); dietary intake (via dietary interview); and appetite (using Appetite and Diet Assessment Tool). Participant demographics were obtained via survey or medical charts. Main outcome measures were inadequate dietary protein intake (anorexia) was reported in 62% (18/29) of participants with inadequate protein malnourished patients reported anorexia versus 12 (23%) of the well-nourished patients (p = 0.0001). Anorexia was a key risk factor for inadequate protein intake and malnutrition in patients undergoing PD. These findings highlight a need to closely monitor patients with appetite disturbances. © 2016 European Dialysis and Transplant Nurses Association/European Renal Care Association.

  6. Local equilibrium in bird flocks

    Science.gov (United States)

    Mora, Thierry; Walczak, Aleksandra M.; Del Castello, Lorenzo; Ginelli, Francesco; Melillo, Stefania; Parisi, Leonardo; Viale, Massimiliano; Cavagna, Andrea; Giardina, Irene

    2016-12-01

    The correlated motion of flocks is an example of global order emerging from local interactions. An essential difference with respect to analogous ferromagnetic systems is that flocks are active: animals move relative to each other, dynamically rearranging their interaction network. This non-equilibrium characteristic has been studied theoretically, but its impact on actual animal groups remains to be fully explored experimentally. Here, we introduce a novel dynamical inference technique, based on the principle of maximum entropy, which accommodates network rearrangements and overcomes the problem of slow experimental sampling rates. We use this method to infer the strength and range of alignment forces from data of starling flocks. We find that local bird alignment occurs on a much faster timescale than neighbour rearrangement. Accordingly, equilibrium inference, which assumes a fixed interaction network, gives results consistent with dynamical inference. We conclude that bird orientations are in a state of local quasi-equilibrium over the interaction length scale, providing firm ground for the applicability of statistical physics in certain active systems.

  7. CFD analysis of laboratory scale phase equilibrium cell operation

    Science.gov (United States)

    Jama, Mohamed Ali; Nikiforow, Kaj; Qureshi, Muhammad Saad; Alopaeus, Ville

    2017-10-01

    For the modeling of multiphase chemical reactors or separation processes, it is essential to predict accurately chemical equilibrium data, such as vapor-liquid or liquid-liquid equilibria [M. Šoóš et al., Chem. Eng. Process.: Process Intensif. 42(4), 273-284 (2003)]. The instruments used in these experiments are typically designed based on previous experiences, and their operation verified based on known equilibria of standard components. However, mass transfer limitations with different chemical systems may be very different, potentially falsifying the measured equilibrium compositions. In this work, computational fluid dynamics is utilized to design and analyze laboratory scale experimental gas-liquid equilibrium cell for the first time to augment the traditional analysis based on plug flow assumption. Two-phase dilutor cell, used for measuring limiting activity coefficients at infinite dilution, is used as a test case for the analysis. The Lagrangian discrete model is used to track each bubble and to study the residence time distribution of the carrier gas bubbles in the dilutor cell. This analysis is necessary to assess whether the gas leaving the cell is in equilibrium with the liquid, as required in traditional analysis of such apparatus. Mass transfer for six different bio-oil compounds is calculated to determine the approach equilibrium concentration. Also, residence times assuming plug flow and ideal mixing are used as reference cases to evaluate the influence of mixing on the approach to equilibrium in the dilutor. Results show that the model can be used to predict the dilutor operating conditions for which each of the studied gas-liquid systems reaches equilibrium.

  8. CFD analysis of laboratory scale phase equilibrium cell operation.

    Science.gov (United States)

    Jama, Mohamed Ali; Nikiforow, Kaj; Qureshi, Muhammad Saad; Alopaeus, Ville

    2017-10-01

    For the modeling of multiphase chemical reactors or separation processes, it is essential to predict accurately chemical equilibrium data, such as vapor-liquid or liquid-liquid equilibria [M. Šoóš et al., Chem. Eng. Process Intensif. 42(4), 273-284 (2003)]. The instruments used in these experiments are typically designed based on previous experiences, and their operation verified based on known equilibria of standard components. However, mass transfer limitations with different chemical systems may be very different, potentially falsifying the measured equilibrium compositions. In this work, computational fluid dynamics is utilized to design and analyze laboratory scale experimental gas-liquid equilibrium cell for the first time to augment the traditional analysis based on plug flow assumption. Two-phase dilutor cell, used for measuring limiting activity coefficients at infinite dilution, is used as a test case for the analysis. The Lagrangian discrete model is used to track each bubble and to study the residence time distribution of the carrier gas bubbles in the dilutor cell. This analysis is necessary to assess whether the gas leaving the cell is in equilibrium with the liquid, as required in traditional analysis of such apparatus. Mass transfer for six different bio-oil compounds is calculated to determine the approach equilibrium concentration. Also, residence times assuming plug flow and ideal mixing are used as reference cases to evaluate the influence of mixing on the approach to equilibrium in the dilutor. Results show that the model can be used to predict the dilutor operating conditions for which each of the studied gas-liquid systems reaches equilibrium.

  9. Study of the method of neutron activation analysis for clinical accompaniment of patients with CRI submitted to the dialysis

    International Nuclear Information System (INIS)

    Santos, Nandizia F.T. dos; Vilela, Eudice Correia; Zamboni, Cibele Bugno; Genezini, Frederico Antonio

    2008-01-01

    Full text: The organism chemical composition knowledge based on laboratory analysis is an important tool for the diagnosis and prognostic of disease. Besides, it is useful for the treatment plan of some pathologies. Amongst the most usually analyzed elements, the electrolytes, whose participation is essential for some metabolic processes, when their concentrations are modified, may become the cause of some diseases. The kidneys have a basic role in the human body chemical composition equilibrium, through its participation in the hydro-electrolyte physiology. It is observed that abnormal values in the concentration of electrolytes in the blood is an easy found characteristic in people suffering of Chronicle Renal Insufficiency-CRI, In a most advanced step of the illness, these patients need to be submitted to the dialysis for substitution of renal system function. In this work the conditions of the Absolute Neutron Activation Analysis (ANAA) method in total blood electrolytes concentration determination were investigated. Concentration data of sodium-Na +, potassium-K +, chlorine-Cl -, and bromine-Br + that are essential elements to the maintenance of the hydro-electrolytic balance of the organisms are shown. This work also intends to propose the ANAA alternative methodology for future clinical IRC patients' accompaniment, collaborating with the supplying information to assist in the diagnosis and therapy of these patients. Compared with other methodologies, the ANAA exclude the use of standards, reducing expenses, employs significantly small amount of biological samples (100μl) and have fast execution (1 h). Samples of total blood of patients with CRI had been collected at Hospital of the Clinics of the UFPE. Four groups of patients were selected and classified in accordance with the type of treatment, dialysis type and time they are submitted to the process. So that, the patients groups were as follows: Conservative Treatment, Peritoneal Dialysis, Dialysis with

  10. Efficacy of Ultrasound-Guided Axillary Brachial Plexus Block for Analgesia During Percutaneous Transluminal Angioplasty for Dialysis Access

    International Nuclear Information System (INIS)

    Chiba, Emiko; Hamamoto, Kohei; Nagashima, Michio; Matsuura, Katsuhiko; Okochi, Tomohisa; Tanno, Keisuke; Tanaka, Osamu

    2016-01-01

    PurposeTo evaluate the efficacy and safety of ultrasound (US)-guided axillary brachial plexus block (ABPB) for analgesia during percutaneous transluminal angioplasty (PTA) for dialysis access.Subjects and MethodsTwenty-one patients who underwent PTA for stenotic dialysis access shunts and who had previous experience of PTA without sedation, analgesia, and anesthesia were included. The access type in all patients was native arteriovenous fistulae in the forearm. Two radiologists performed US-guided ABPB for the radial and musculocutaneous nerves before PTA. The patients’ pain scores were evaluated using a visual analog scale (VAS) after PTA, and these were compared with previous sessions without US-guided ABPB. The patient’s motor/sensory paralysis after PTA was also examined.ResultsThe mean time required to achieve US-guided ABPB was 8 min. The success rate of this procedure was 100 %, and there were no significant complications. All 21 patients reported lower VAS with US-guided ABPB as compared to without the block (p < 0.01). All patients expressed the desire for an ABPB for future PTA sessions, if required. Transient motor paralysis occurred in 8 patients, but resolved in all after 60 min.ConclusionUS-guided ABPB is feasible and effective for analgesia in patients undergoing PTA for stenotic dialysis access sites.Level of EvidenceLevel 4 (case series).

  11. Efficacy of Ultrasound-Guided Axillary Brachial Plexus Block for Analgesia During Percutaneous Transluminal Angioplasty for Dialysis Access

    Energy Technology Data Exchange (ETDEWEB)

    Chiba, Emiko, E-mail: chibaemi23@comet.ocn.ne.jp; Hamamoto, Kohei, E-mail: hkouhei917@gmail.com [Jichi Medical University, Department of Radiology, Saitama Medical Center (Japan); Nagashima, Michio, E-mail: nagamic00@gmail.com [Asahikawa Medical University, Department of Emergency Medicine (Japan); Matsuura, Katsuhiko, E-mail: kmatsur@gmail.com; Okochi, Tomohisa, E-mail: t-shachi@dj8.so-net.ne.jp; Tanno, Keisuke, E-mail: tankichi1974@gmail.com; Tanaka, Osamu, E-mail: otanaka@omiya.jichi.ac.jp [Jichi Medical University, Department of Radiology, Saitama Medical Center (Japan)

    2016-10-15

    PurposeTo evaluate the efficacy and safety of ultrasound (US)-guided axillary brachial plexus block (ABPB) for analgesia during percutaneous transluminal angioplasty (PTA) for dialysis access.Subjects and MethodsTwenty-one patients who underwent PTA for stenotic dialysis access shunts and who had previous experience of PTA without sedation, analgesia, and anesthesia were included. The access type in all patients was native arteriovenous fistulae in the forearm. Two radiologists performed US-guided ABPB for the radial and musculocutaneous nerves before PTA. The patients’ pain scores were evaluated using a visual analog scale (VAS) after PTA, and these were compared with previous sessions without US-guided ABPB. The patient’s motor/sensory paralysis after PTA was also examined.ResultsThe mean time required to achieve US-guided ABPB was 8 min. The success rate of this procedure was 100 %, and there were no significant complications. All 21 patients reported lower VAS with US-guided ABPB as compared to without the block (p < 0.01). All patients expressed the desire for an ABPB for future PTA sessions, if required. Transient motor paralysis occurred in 8 patients, but resolved in all after 60 min.ConclusionUS-guided ABPB is feasible and effective for analgesia in patients undergoing PTA for stenotic dialysis access sites.Level of EvidenceLevel 4 (case series).

  12. Quantum dynamical semigroups and approach to equilibrium

    International Nuclear Information System (INIS)

    Frigerio, A.

    1977-01-01

    For a quantum dynamical semigroup possessing a faithful normal stationary state, some conditions are discussed, which ensure the uniqueness of the equilibrium state and/or the approach to equilibrium for arbitrary initial condition. (Auth.)

  13. Non-equilibrium many body dynamics

    International Nuclear Information System (INIS)

    Creutz, M.; Gyulassy, M.

    1997-01-01

    This Riken BNL Research Center Symposium on Non-Equilibrium Many Body Physics was held on September 23-25, 1997 as part of the official opening ceremony of the Center at Brookhaven National Lab. A major objective of theoretical work at the center is to elaborate on the full spectrum of strong interaction physics based on QCD, including the physics of confinement and chiral symmetry breaking, the parton structure of hadrons and nuclei, and the phenomenology of ultra-relativistic nuclear collisions related to the up-coming experiments at RHIC. The opportunities and challenges of nuclear and particle physics in this area naturally involve aspects of the many body problem common to many other fields. The aim of this symposium was to find common theoretical threads in the area of non-equilibrium physics and modern transport theories. The program consisted of invited talks on a variety topics from the fields of atomic, condensed matter, plasma, astrophysics, cosmology, and chemistry, in addition to nuclear and particle physics. Separate abstracts have been indexed into the database for contributions to this workshop

  14. Non-equilibrium many body dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Creutz, M.; Gyulassy, M.

    1997-09-22

    This Riken BNL Research Center Symposium on Non-Equilibrium Many Body Physics was held on September 23-25, 1997 as part of the official opening ceremony of the Center at Brookhaven National Lab. A major objective of theoretical work at the center is to elaborate on the full spectrum of strong interaction physics based on QCD, including the physics of confinement and chiral symmetry breaking, the parton structure of hadrons and nuclei, and the phenomenology of ultra-relativistic nuclear collisions related to the up-coming experiments at RHIC. The opportunities and challenges of nuclear and particle physics in this area naturally involve aspects of the many body problem common to many other fields. The aim of this symposium was to find common theoretical threads in the area of non-equilibrium physics and modern transport theories. The program consisted of invited talks on a variety topics from the fields of atomic, condensed matter, plasma, astrophysics, cosmology, and chemistry, in addition to nuclear and particle physics. Separate abstracts have been indexed into the database for contributions to this workshop.

  15. Dialysis Exercise Team: The Way to Sustain Exercise Programs in Hemodialysis Patients

    Directory of Open Access Journals (Sweden)

    Alessandro Capitanini

    2014-07-01

    Full Text Available Patients affected by end-stage renal disease (ESRD show quite lower physical activity and exercise capacity when compared to healthy individuals. In addition, a sedentary lifestyle is favoured by lack of a specific counseling on exercise implementation in the nephrology care setting. Increasing physical activity level should represent a goal for every dialysis patient care management. Three crucial elements of clinical care may contribute to sustain a hemodialysis exercise program: a involvement of exercise professionals, b real commitment of nephrologists and dialysis professionals, c individual patient adaptation of the exercise program. Dialysis staff have a crucial role to encourage and assist patients during intra-dialysis exercise, but other professionals should be included in the ideal “exercise team” for dialysis patients. Evaluation of general condition, comorbidities (especially cardiovascular, nutritional status and physical exercise capacity are mandatory to propose an exercise program, in either extra-dialysis or intra-dialysis setting. To this aim, nephrologist should lead a team of specialists and professionals including cardiologist, physiotherapist, exercise physiologist, renal dietician and nurse. In this scenario, dialysis nurses play a pivotal role since they guarantee a constant and direct approach. Unfortunately dialysis staff may often lack of information and formation about exercise management while they take care patients during the dialysis session. Building an effective exercise team, promoting the culture of exercise and increasing physical activity levels lead to a more complete and modern clinical care management of ESRD patients.

  16. Thermodynamics of the Rhodamine B Lactone--Zwitterion Equilibrium.

    Science.gov (United States)

    Hinckley, Daniel A.; Seybold, Paul G.

    1987-01-01

    Discusses the benefits of thermochromic transformations for studying thermodynamic properties. Describes an experiment that uses a commercially available dye, attains equilibrium rapidly, employs a simple, single-beam spectrophotometer, and is suitable for both physical chemistry and introductory chemistry laboratories. (TW)

  17. Equilibrium and kinetics studies of metal ion adsorption on dyed ...

    African Journals Online (AJOL)

    GREGO

    2007-04-02

    Apr 2, 2007 ... Initial concentration of Cu(II) ions = 20 mg/l, adsorbent dose = 1.0 g. Table 2 Experiment Data of ... diffusivity of the metal ion would be independent of the extent of sorption .... exchange and adsorption. Equilibrium parameter.

  18. On the ionic equilibrium between complexes in molten fluoroaluminates

    International Nuclear Information System (INIS)

    Akdeniz, Z.; Tankeshwar, K.; Tosi, M.P.

    1991-02-01

    We discuss theoretically (i) the effect of the alkali cation species on the ionic equilibrium between (AlF 6 ) 3- and (AlF 4 ) - complexes in molten alkali fluoroaluminates, and (ii) the possible presence of (AlF 5 ) 2 - complexes in molten cryolite, in relation to very recent Raman scattering experiments by Gilbert and Materne. (author). 7 refs, 2 tabs

  19. Investigation of Chemical Equilibrium Kinetics by the Electromigration Method

    CERN Document Server

    Bozhikov, G A; Bontchev, G D; Maslov, O D; Milanov, M V; Dmitriev, S N

    2002-01-01

    Measurement of the chemical reaction rates for complex formation as well as hydrolysis type reactions by the method of horizontal zone electrophoresis is outlined. The correlation between chemical equilibrium kinetics and electrodiffusion processes in a constant d.c. electric field is described. In model electromigration experiments the reaction rate constant of the complex formation of Hf(IV) and DTPA is determined.

  20. 2-D skin-current toroidal-MHD-equilibrium code

    International Nuclear Information System (INIS)

    Feinberg, B.; Niland, R.A.; Coonrod, J.; Levine, M.A.

    1982-09-01

    A two-dimensional, toroidal, ideal MHD skin-current equilibrium computer code is described. The code is suitable for interactive implementation on a minicomptuer. Some examples of the use of the code for design and interpretation of toroidal cusp experiments are presented

  1. The geometry of finite equilibrium sets

    DEFF Research Database (Denmark)

    Balasko, Yves; Tvede, Mich

    2009-01-01

    We investigate the geometry of finite datasets defined by equilibrium prices, income distributions, and total resources. We show that the equilibrium condition imposes no restrictions if total resources are collinear, a property that is robust to small perturbations. We also show that the set...... of equilibrium datasets is pathconnected when the equilibrium condition does impose restrictions on datasets, as for example when total resources are widely noncollinear....

  2. Accelerating Multiagent Reinforcement Learning by Equilibrium Transfer.

    Science.gov (United States)

    Hu, Yujing; Gao, Yang; An, Bo

    2015-07-01

    An important approach in multiagent reinforcement learning (MARL) is equilibrium-based MARL, which adopts equilibrium solution concepts in game theory and requires agents to play equilibrium strategies at each state. However, most existing equilibrium-based MARL algorithms cannot scale due to a large number of computationally expensive equilibrium computations (e.g., computing Nash equilibria is PPAD-hard) during learning. For the first time, this paper finds that during the learning process of equilibrium-based MARL, the one-shot games corresponding to each state's successive visits often have the same or similar equilibria (for some states more than 90% of games corresponding to successive visits have similar equilibria). Inspired by this observation, this paper proposes to use equilibrium transfer to accelerate equilibrium-based MARL. The key idea of equilibrium transfer is to reuse previously computed equilibria when each agent has a small incentive to deviate. By introducing transfer loss and transfer condition, a novel framework called equilibrium transfer-based MARL is proposed. We prove that although equilibrium transfer brings transfer loss, equilibrium-based MARL algorithms can still converge to an equilibrium policy under certain assumptions. Experimental results in widely used benchmarks (e.g., grid world game, soccer game, and wall game) show that the proposed framework: 1) not only significantly accelerates equilibrium-based MARL (up to 96.7% reduction in learning time), but also achieves higher average rewards than algorithms without equilibrium transfer and 2) scales significantly better than algorithms without equilibrium transfer when the state/action space grows and the number of agents increases.

  3. The Geometry of Finite Equilibrium Datasets

    DEFF Research Database (Denmark)

    Balasko, Yves; Tvede, Mich

    We investigate the geometry of finite datasets defined by equilibrium prices, income distributions, and total resources. We show that the equilibrium condition imposes no restrictions if total resources are collinear, a property that is robust to small perturbations. We also show that the set...... of equilibrium datasets is pathconnected when the equilibrium condition does impose restrictions on datasets, as for example when total resources are widely non collinear....

  4. Impact of global economic disparities on practices and outcomes of chronic peritoneal dialysis in children: insights from the International Pediatric Peritoneal Dialysis Network Registry

    NARCIS (Netherlands)

    Schaefer, Franz; Borzych-Duzalka, Dagmara; Azocar, Marta; Munarriz, Reyner Loza; Sever, Lale; Aksu, Nejat; Barbosa, Lorena Sànchez; Galan, Yajaira Silva; Xu, Hong; Coccia, Paula A.; Szabo, Attila; Wong, William; Salim, Rosana; Vidal, Enrico; Pottoore, Stephen; Warady, Bradley A.; Alconcher, L.; Sojo, E.; Coccia, P. A.; Suarez, A.; Valles, P. G.; Salim, R.; Salta, S. A.; van Hoeck, K.; Koch, V.; Feber, J.; Geary, D. A.; White, C.; Valenzuela, M.; Villagra, J.; Cano, F.; Contreras, M. A.; Vogel, A.; Zambrano, P.; Berrocal, P.; Tse, K. C.; Xu, H.; Vondrak, K.; Rönnholm, K.; Harambat, J.; Ranchin, B.; Roussey, G.; Ulinski, T.; Fischbach, M.; Büscher, R.; Kemper, M.; Pape, L.; Schaefer, F.; Borzych, D.; Groothoff, J. W.

    2012-01-01

    BACKGROUND, OBJECTIVES, AND METHODS: The number of patients on chronic peritoneal dialysis (CPD) is increasing rapidly on a global scale. We analyzed the International Pediatric Peritoneal Dialysis Network (IPPN) registry, a global database active in 33 countries spanning a wide range in gross

  5. Open problems in non-equilibrium physics

    International Nuclear Information System (INIS)

    Kusnezov, D.

    1997-01-01

    The report contains viewgraphs on the following: approaches to non-equilibrium statistical mechanics; classical and quantum processes in chaotic environments; classical fields in non-equilibrium situations: real time dynamics at finite temperature; and phase transitions in non-equilibrium conditions

  6. The concept of equilibrium in organization theory

    NARCIS (Netherlands)

    Gazendam, H.W.M.

    1998-01-01

    Many organization theories consist of an interpretation frame and an idea about the ideal equilibrium state. This article explains how the equilibrium concept is used in four organization theories: the theories of Fayol, Mintzberg, Morgan, and Volberda. Equilibrium can be defined as balance, fit or

  7. The concept of equilibrium in organization theory

    NARCIS (Netherlands)

    Gazendam, Henk W.M.

    1997-01-01

    Many organization theories consist of an interpretation frame and an idea about the ideal equilibrium state. This article explains how the equilibrium concept is used in four organization theories: the theories of Fayol, Mintzberg, Morgan, and Volberda. Equilibrium can be defined as balance, fit or

  8. Open problems in non-equilibrium physics

    Energy Technology Data Exchange (ETDEWEB)

    Kusnezov, D.

    1997-09-22

    The report contains viewgraphs on the following: approaches to non-equilibrium statistical mechanics; classical and quantum processes in chaotic environments; classical fields in non-equilibrium situations: real time dynamics at finite temperature; and phase transitions in non-equilibrium conditions.

  9. Asymptomatic Effluent Protozoa Colonization in Peritoneal Dialysis Patients.

    Science.gov (United States)

    Simões-Silva, Liliana; Correia, Inês; Barbosa, Joana; Santos-Araujo, Carla; Sousa, Maria João; Pestana, Manuel; Soares-Silva, Isabel; Sampaio-Maia, Benedita

    Currently, chronic kidney disease (CKD) is a global health problem. Considering the impaired immunity of CKD patients, the relevance of infection in peritoneal dialysis (PD), and the increased prevalence of parasites in CKD patients, protozoa colonization was evaluated in PD effluent from CKD patients undergoing PD. Overnight PD effluent was obtained from 49 asymptomatic stable PD patients. Protozoa analysis was performed microscopically by searching cysts and trophozoites in direct wet mount of PD effluent and after staining smears. Protozoa were found in PD effluent of 10.2% of evaluated PD patients, namely Blastocystis hominis, in 2 patients, and Entamoeba sp., Giardia sp., and Endolimax nana in the other 3 patients, respectively. None of these patients presented clinical signs or symptoms of peritonitis at the time of protozoa screening. Our results demonstrate that PD effluent may be susceptible to asymptomatic protozoa colonization. The clinical impact of this finding should be further investigated. Copyright © 2016 International Society for Peritoneal Dialysis.

  10. Circulating thyroid hormone levels and adequacy of dialysis.

    Science.gov (United States)

    Savdie, E; Stewart, J H; Mahony, J F; Hayes, J M; Lazarus, L; Simons, L A

    1978-02-01

    In vitro thyroid function tests were performed in three groups of patients with chronic renal failure who were receiving, on average, 15, 18 and 27 hours of maintenance hemodialysis per week. Total thyroxine levels were low and total triiodothyronine levels low to normal in those receiving the least dialysis (15 hours), and were significantly higher in those receiving longer dialysis. Free thyroxine levels, as measured by the effective thyroxine ratio, were normal and similar in all three groups, as were serum thyrotrophin levels. All patients were clinically euthyroid. As total hormone levels showed a significant inverse relationship to both urea and creatinine, this study suggests that there is a dialyzable metabolite retained in uremia which competes with thyroid hormones for protein-binding sites.

  11. [Just-in-time initiation of optimal dialysis].

    Science.gov (United States)

    Cornelis, Tom; Kooman, Jeroen P; van der Sande, Frank M

    2010-01-01

    The IDEAL trial shows that the decision to start renal replacement treatment should not depend on GFR alone, but should be taken on the basis of clinical parameters. Quality of Life (QoL) questionnaires and bio-impedance analysis are potential tools for detecting subtle changes in the predialysis clinic. Too early an initiation of dialysis may be deleterious for the patient and the healthcare system. We are convinced that ESRD patients should be informed about intensive haemodialysis (HD), especially nocturnal (home) HD, as the best available dialysis modality. There is substantial evidence which shows that intensive HD improves clinical, biochemical and biological parameters, and may even prolong survival. We believe that 'just-in-time delivery of intensive haemodialysis' may result in optimised QoL and reduced economic burden.

  12. Severe valproate induced hyperammonemic encephalopathy successfully managed with peritoneal dialysis.

    Science.gov (United States)

    Kumar, Amandeep; Suri, Ashish; Sharma, Bhawani S

    2014-07-01

    Valproic acid (VPA) is a commonly used drug for epilepsy, psychiatric disorders and migraine and is frequently used in neurosurgical intensive care units. Though most of its side-effects are mild and transient, certain idiosyncratic side-effects have been attributed to VPA. Valproate induced hyperammonemia (VIH) is one such side-effect. VIH can produce symptoms of encephalopathy known as valproate induced hyperammonemic encephalopathy (VHE). VIH and VHE usually respond to withdrawal of VPA. However, in some cases VHE can be unresponsive to supportive measures and severe enough to be life-threatening. In such cases, dialysis can be used to rapidly reverse hyperammonemia and VHE and can prove to be a lifesaving measure. We report such a case of VIH and life-threatening VHE in a postoperative neurosurgical patient that was managed successfully with peritoneal dialysis.

  13. Two Cases of Massive Hydrothorax Complicating Peritoneal Dialysis

    International Nuclear Information System (INIS)

    Bae, Sang Kyun; Yum, Ha Yong; Rim, Hark

    1994-01-01

    Massive hydrothorax complicating continuous ambulatory peritoneal dialysis (CAPD) is relatively rare. A 67-year-old male and a 23-year-old female patients during CAPD presented massive pleural effusion, They have been performing peritoneal dialysis due to end-stage renal disease for 8 months and 2 weeks respectively. We injected '9 9m Tc-labelled radiopharmaceutical (phytate and MAA, respectively) into peritoneal cavity with the dialysate. The anterior, posterior and right lateral images were obtained. The studies reveal visible radioactivity in the right chest indicating the communication between the peritoneal and the pleural space. After sclerotherapy with tetracycline, the same studies reveal no radioactivity in the right chest suggesting successful therapy. We think nuclear imaging is a simple and noninvasive method for the differential diagnosis of pleural effusion in patients during CAPD and the evaluation of therapy.

  14. Abdominal aortic calcifications predict survival in peritoneal dialysis patients

    DEFF Research Database (Denmark)

    Mäkelä, Satu M; Asola, Markku; Hadimeri, Henrik

    2018-01-01

    BACKGROUND: Peripheral arterial disease and vascular calcifications contribute significantly to the outcome of dialysis patients. The aim of this study was to evaluate the prognostic role of severity of abdominal aortic calcifications and peripheral arterial disease on outcome of peritoneal...... dialysis (PD) patients using methods easily available in everyday clinical practice. METHODS: We enrolled 249 PD patients (mean age 61 years, 67% male) in this prospective, observational, multicenter study from 2009 to 2013. The abdominal aortic calcification score (AACS) was assessed using lateral lumbar.......9) in 17%, and high (> 1.3) in 34% of patients. Altogether 91 patients (37%) died during the median follow-up of 46 months. Only 2 patients (5%) with AACS 0 died compared with 50% of the patients with AACS ≥ 7 (p

  15. The dynamic process of adherence to a renal therapeutic regimen: perspectives of patients undergoing continuous ambulatory peritoneal dialysis.

    Science.gov (United States)

    Lam, Lai Wah; Lee, Diana T F; Shiu, Ann T Y

    2014-06-01

    The nature of end-stage renal disease and the need for continuous ambulatory peritoneal dialysis require patients to manage various aspects of the disease, its symptoms and treatment. After attending a training programme, patients are expected to adhere to the renal therapeutic regimen and manage their disease with the knowledge and skills learned. While patients are the stakeholders of their health and related behaviour, their perceptions of adherence and how they adhere to their renal therapeutic regimen remains unexplored. To understand adherence from patients' perspectives and to describe changes in adherence to a therapeutic regimen among patients undergoing continuous ambulatory peritoneal dialysis. This study used a mixed methods design with two phases - a survey in phase I and semi-structured interviews in phase II. This paper presents phase II of the study. The study was conducted at a renal unit of an acute hospital in Hong Kong. Based on the phase I survey results, maximum variation sampling was employed to purposively recruit 36 participants of different genders (18 males, 18 females), ages (35-76 years), and lengths of dialysis experience (11-103 months) for the phase II interviews. Data were collected by tape-recorded semi-structured interviews. Content analysis was employed to analyse the transcribed data. Data collection and analysis were conducted simultaneously. Adherence was a dynamic process with three stages. At the stage of initial adherence, participants attempted to follow instructions but found that strict persistent adherence was impossible. After the first 2-6 months of dialysis, participants entered the stage of subsequent adherence, when they adopted selective adherence through experimenting, monitoring and making continuous adjustments. The stage of long-term adherence commenced after 3-5 years of dialysis, when participants were able to assimilate the modified therapeutic regimen into everyday life. The process of adherence was

  16. Characteristics of equilibrium and perturbed transport coefficients in tokamaks

    International Nuclear Information System (INIS)

    Gentle, K.W.

    1995-01-01

    Although the evolution of a perturbation to a tokamak equilibrium can generally be described by local transport coefficients modestly enhanced above the equilibrium values, there are some significant cases for which this is inadequate. The density profile evolution in ASDEX-U occurs far more rapidly than is consistent with reasonable particle confinement times, and the evolution of cold pulses in TEXT requires nonlocal behavior in the core and some kind of anomaly near the periphery. The experiments are suggesting effects beyond standard local turbulent transport models. (orig.)

  17. Comparative clinical outcomes between pediatric and young adult dialysis patients.

    Science.gov (United States)

    Atkinson, Meredith A; Lestz, Rachel M; Fivush, Barbara A; Silverstein, Douglas M

    2011-12-01

    Published data on the comparative achievement of The Kidney Disease Dialysis Outcome Quality Initiative (KDOQI) recommended clinical performance targets between children and young adults on dialysis are scarce. To characterize the achievement of KDOQI targets among children (young adults (18-24 years) with prevalent end stage renal disease (ESRD), we performed a cross-sectional analysis of data collected by the Mid-Atlantic Renal Coalition, in conjunction with the 2007 and 2008 ESRD Clinical Performance Measures Projects. Data on all enrolled pediatric dialysis patients, categorized into three age groups (0-8, 9-12, 13-17 years), and on a random sample of 5% of patients ≥ 18 years in ESRD Network 5 were examined for two study periods: hemodialysis (HD) data were collected from October to December 2006 and from October to December 2007 and peritoneal dialysis (PD) data were collected from October 2006 to March 2007 and from October 2007 to March 2008. In total, 114 unique patients were enrolled the study, of whom 41.2% (47/114) were on HD and 58.8% (67/114) on PD. Compared to the pediatric patients, young adults were less likely to achieve the KDOQI recommended serum phosphorus levels and serum calcium × phosphorus product values, with less than one-quarter demonstrating values at or below each goal. Multivariate analysis revealed that both young adults and 13- to 17-year-olds were less likely to achieve target values for phosphorus [young adults: odds ratio (OR) 0.04, 95% confidence interval (95% CI) 0.01-0.19, p young adults: OR 0.01, 95% CI 0.002-0.09, p young adult ESRD patients.

  18. Croatian Recommendations for Dialysis of HIV-Positive Patients

    Directory of Open Access Journals (Sweden)

    Gulin Marijana

    2016-06-01

    Full Text Available Human immunodeficiency virus (HIV infection may be associated with renal impairment since about 0.4% of all HIV-positive patients develop end-stage renal disease. The share of patients with HIV infection in hemodialysis centers throughout the world ranges from 0.3% to as high as 38%. In Croatia, renal replacement therapy was needed by 1% of all the HIV-positive patients from 1985 until the end of 2014. Healthcare professionals (HP should be aware of the risks of occupational exposure to blood-borne infections in their daily work. Performing dialysis in HIV-positive patients increases the risk of exposure to HIV during the extracorporeal circulation of the infected blood. However, post-exposure prophylaxis (PEP with effective antiretroviral drugs significantly reduces the risk of infection after occupational exposure. On behalf of the Croatian Society of Nephrology, Dialysis and Transplantation, the authors of this paper have proposed recommendations for the management of HIVpositive patients on dialysis, which aim to prevent the transmission of HIV among patients and HPs. The important recommendations include the following: 1. when the need arises, it is necessary to provide HIV-positive patients with dialysis in the vicinity of their place of residence. 2. HIV-positive patients should be dialyzed with a separate hemodialysis machine in an isolated area. Alternatively, they can be dialyzed in an area for the hemodialysis of HCV-positive and/or HBVpositive patients. 3. Specialized and trained personnel should be provided during the hemodialysis procedure, together with strict compliance with the standard precautions for the prevention of blood-borne infections. 4. There should be a good and prompt cooperation with the National Referral Center for HIV infection.

  19. Cardiovascular morbidity and mortality risk factors in peritoneal dialysis patients

    Directory of Open Access Journals (Sweden)

    Jovanović Dijana B.

    2008-01-01

    Full Text Available Cardiovascular (CVS morbidity and mortality in the endstage renal disease (ESRD patients on peritoneal dialysis therapy is 10-30 folds higher than in general population. The prevalence of well known traditional risk factors such as age, sex, race, arterial hypertension, hyperlipidaemia, diabetes, smoking, physical inactivity is higher in the uraemic patients. Besides these, there are specific, nontraditional risk factors for dialysis patients. Mild inflammation present in peritoneal dialysis (PD patients which can be confirmed by specific inflammatory markers is the cause of CVS morbidity and mortality in these patients. Hypoalbuminaemia, hyperhomocysteinaemia and a higher level of leptin are important predictors of vascular complications as well as CVS events in the PD patients. Plasma norepinephrine, an indicator of sympathetic activity, is high in the ESRD patients and higher in the PD patients than in the patients on haemodialysis (HD. Therefore, norepinephrine may be a stronger risk factor in the PD patients. The same applies to asymmetric dimethylargine (ADMA, an endogenous inhibitor of nitric oxide synthase, which is an important risk factor of CVS morbidity and mortality 15 % higher in the PD than the HD patients. Hyperphosphataemia, secondary hyperparathyroidism and high calcium x phosphate product have been associated with the progression of the coronary artery calcification and valvular calcifications and predict all-cause CVS mortality in the PD patients. Residual renal function (RRF declines with time on dialysis but is slower in the PD than the HD patients. RRF decline is associated with the rise of proinflammatory cytokines and the onset of hypervolaemia and hypertension which increase the risk of CVS diseases, mortality in general and CVS mortality. In conclusion, it is very important to establish all CVS risk factors in the PD patients to prevent CVS diseases and CVS mortality in this population.

  20. Exercising during dialysis: a reflection on environmental\\ud barriers

    OpenAIRE

    Meddick, Leighan

    2016-01-01

    Research has demonstrated that exercise provides several physical and psychological benefits for hemodialysis patients, which include increasing their quality of life. However, implementing intra-dialytic exercise into the patients’ care schemes often proves to be a difficult task for dialysis providers, and they often run into barriers. Some of the environmental barriers that are often experienced are discussed herein, in order to raise awareness and provide recommendations which may result ...

  1. High fall incidence and fracture rate in elderly dialysis patients.

    Science.gov (United States)

    Polinder-Bos, H A; Emmelot-Vonk, M H; Gansevoort, R T; Diepenbroek, A; Gaillard, C A J M

    2014-12-01

    Although it is recognised that the dialysis population is ageing rapidly, geriatric complications such as falls are poorly appreciated, despite the many risk factors for falls in this population. The objective of this study was to determine the incidence, complications and risk factors for falls in an elderly dialysis population. A one-year observational study of chronic dialysis patients aged ≥ 70 years. At baseline, patient characteristics were noted and during follow-up the vital parameters and laboratory values were recorded. Patients were questioned weekly about falls, fall circumstances and consequences by trained nurses. 49 patients were included with a median age of 79.3 years (70-89 years). During follow-up 40 fall accidents occurred in 27 (55%) patients. Falls resulted in fractures in 15% of cases and in hospital admissions in 15%. In haemodialysis (HD) patients, the mean systolic blood pressure (SBP) before HD was lower in fallers compared with non-fallers (130 vs. 143 mmHg). Several patients in the lower blood pressure category received antihypertensive medication. For every 5 mmHg lower SBP (before HD) the fall risk increased by 30% (hazard ratio (HR) 1.30, 95% CI 1.03-1.65, p = 0.03). Furthermore, fall risk increased by 22% for every 10 pmol/l rise of parathyroid hormone (HR 1.22, 95% CI 1.06-1.39, p = 0.004). Elderly dialysis patients have a high incidence of falls accompanied by a high fracture rate. Given the high complication rate, elderly patients at risk of falling should be identified and managed. Reduction of blood pressure-lowering medication might be a treatment strategy to reduce falls.

  2. Peritoneal dialysis peritonitis by anaerobic pathogens: a retrospective case series

    OpenAIRE

    Chao, Chia-Ter; Lee, Szu-Ying; Yang, Wei-Shun; Chen, Huei-Wen; Fang, Cheng-Chung; Yen, Chung-Jen; Chiang, Chih-Kang; Hung, Kuan-Yu; Huang, Jenq-Wen

    2013-01-01

    Background Bacterial infections account for most peritoneal dialysis (PD)-associated peritonitis episodes. However, anaerobic PD peritonitis is extremely rare and intuitively associated with intra-abdominal lesions. In this study, we examined the clinical characteristics of PD patients who developed anaerobic peritonitis. Methods We retrospectively identified all anaerobic PD peritonitis episodes from a prospectively collected PD registry at a single center between 1990 and 2010. Only patient...

  3. Adverse Effects of Sporadic Dialysis on Body Composition.

    Science.gov (United States)

    Workeneh, Biruh; Shypailo, Roman; DeCastro, Iris; Shah, Maulin; Guffey, Danielle; Minard, Charles G; Mitch, William E

    2015-01-01

    The aim of this study is to analyze the body composition of patients receiving emergent dialysis and compare their body cell mass (BCM) and fat-free mass (FFM) with those of normal subjects. The care of patients receiving sporadic, emergent dialysis treatment is a growing public health concern and the magnitude of muscle wasting that occurs in this population is not known. We used a cross-sectional design with matching to determine differences in total body potassium--an indicator of both BCM and FFM--between emergent dialysis patients and healthy normal subjects. We studied 22 subjects using a 40K counter that measures BCM and FFM and compared them to controls after matching with sex, height and weight. In the matched comparison, BCM and FFM were significantly lower in subjects with end-stage renal disease (ESRD). Unadjusted BCM was 4.7 kg lower and FFM was 8.8 kg lower for those with ESRD compared to those without ESRD (p FFM (7.7 kg) in the ESRD subjects (p = 0.004). After adjusting for age, height, weight and gender, BCM and FFM were lower by 4.2 and 7.8 kg, respectively (p FFM loss over time was significant, with the ESRD subjects demonstrating 2.2 kg per year decline (p = 0.01). We conclude that among other consequences, muscle wasting indicated by decline in BCM and FFM is a significant concern in the growing emergent dialysis population. © 2015 S. Karger AG, Basel.

  4. Exploring the opinion of hemodialysis patients about their dialysis unit

    OpenAIRE

    Ahmed Farouk Donia; Mohamed Ahmed Elhadedy; Hanzada Mohamed El-Maghrabi; Mohamed Hamed Abbas; Mohamed Ashraf Foda

    2015-01-01

    Hemodialysis (HD) patients are subjected to a number of physical and mental stresses. Physicians might be unaware of some of these problems. We assessed our patients′ opinion about the service provided at the dialysis unit. Our unit has 89 patients on HD. A questionnaire exploring our patients′ opinion relative to the service provided was prepared. The patients were asked to fill-in the questionnaire in a confidential manner. Questionnaires were then collected and examined while unaware of pa...

  5. Efficacy of peritoneal dialysis during infusion and drainage procedures.

    Science.gov (United States)

    Baczyski, Daniel; Antosiewicz, Stefan; Waniewski, Jacek; Nowak, Zbigniew; Wakowicz, Zofia

    2010-01-01

    Inadequate dialysis is still a major cause of technique failure in peritoneal dialysis (PD). Mathematical models provide the possibility of direct and precise assessment of peritoneal transport of urea and creatinine throughout the dwell and allow calculation of optimal schedules, dwell times, and predicted adequacy of a prescribed regimen. Kinetic modeling is particularly important for automated PD. If the effectiveness of uremic toxin removal that takes place during infusion and drainage of dialysis fluid is not taken into account, the predicted adequacy of the whole PD session may be underestimated. ♢ To estimate the efficacy of urea and creatinine removal during the dialysis fluid exchange procedure. ♢ 17 patients treated with PD were included in the study. PD effectiveness during dialysate exchange was defined as the quotient k of removed amount of creatinine/BUN during the infusion and drainage of dialysate and during a dwell of the same duration as the dialysate exchange. ♢ The effectiveness of creatinine and urea removal was reduced during the exchange procedure (k(creat) = 0.68 ± 0.43 and k(BUN) = 0.87 ± 0.44) and differed between these 2 solutes (p = 0.0009). The k coefficients for urea and creatinine were well correlated (R(2) = 0.83). ♢ The effectiveness of peritoneal transport of creatinine and BUN during the inflow/outflow phase was relatively high compared to that during the same dwell time (68% and 87% respectively). This real effectiveness of the dialysate exchange procedure should be taken into account in the process of planning automated PD sessions, otherwise the predicted overall efficacy of creatinine and urea removal throughout the session may be underestimated. This underestimation is proportional to the number of dwells per day.

  6. [Acid-base status in patients treated with peritoneal dialysis].

    Science.gov (United States)

    Katalinić, Lea; Blaslov, Kristina; Pasini, Eva; Kes, Petar; Bašić-Jukić, Nikolina

    2014-04-01

    When compared to hemodialysis, peritoneal dialysis is very simple yet low cost method of renal replacement therapy. Series of studies have shown its superiority in preserving residual renal function, postponing uremic complications, maintaining the acid-base balance and achieving better post-transplant outcome in patients treated with this method. Despite obvious advantages, its role in the treatment of chronic kidney disease is still not as important as it should be. Metabolic acidosis is an inevitable complication associated with progressive loss of kidney function. Its impact on mineral and muscle metabolism, residual renal function, allograft function and anemia is very complex but can be successfully managed. The aim of our study was to evaluate the efficiency in preserving the acid-base balance in patients undergoing peritoneal dialysis at Zagreb University Hospital Center. Twenty-eight patients were enrolled in the study. The mean time spent on the treatment was 32.39 ± 43.43 months. Only lactate-buffered peritoneal dialysis fluids were used in the treatment. Acid-base balance was completely maintained in 73.07% of patients; 11.54% of patients were found in the state of mild metabolic acidosis, and the same percentage of patients were in the state of mild metabolic alkalosis. In one patient, mixed alkalosis with respiratory and metabolic component was present. The results of this study showed that acid-base balance could be maintained successfully in patients undergoing peritoneal dialysis, even only with lactate-buffered solutions included in the treatment, although they were continuously proclaimed as inferior in comparison with bicarbonate-buffered ones. In well educated and informed patients who carefully use this method, accompanied by the attentive and thorough care of their physicians, this method can provide quality continuous replacement of lost renal function as well as better quality of life.

  7. Disseminated Mycobacterium abscessus infection in a peritoneal dialysis patient

    Directory of Open Access Journals (Sweden)

    Vincent H.J.F. Mooren

    2017-01-01

    Full Text Available A disseminated peritoneal dialysis-related Mycobacterium abscessus infection is very rare. M. abscessus belongs to the rapidly growing mycobacteria and can be misidentified as a diphtheroid bacterium, which in our case delayed diagnosis and optimal treatment. Due to intrinsic resistance to most antimicrobials, therapeutic options in M. abscessus infections are limited. Infection often leads to catheter loss. A fatal outcome, like in our case, is not exceptional.

  8. Metabolic Profiling of Impaired Cognitive Function in Patients Receiving Dialysis

    OpenAIRE

    Kurella Tamura, Manjula; Chertow, Glenn M.; Depner, Thomas A.; Nissenson, Allen R.; Schiller, Brigitte; Mehta, Ravindra L.; Liu, Sai; Sirich, Tammy L.

    2016-01-01

    Retention of uremic metabolites is a proposed cause of cognitive impairment in patients with ESRD. We used metabolic profiling to identify and validate uremic metabolites associated with impairment in executive function in two cohorts of patients receiving maintenance dialysis. We performed metabolic profiling using liquid chromatography/mass spectrometry applied to predialysis plasma samples from a discovery cohort of 141 patients and an independent replication cohort of 180 patients partici...

  9. Modelling of an homogeneous equilibrium mixture model

    International Nuclear Information System (INIS)

    Bernard-Champmartin, A.; Poujade, O.; Mathiaud, J.; Mathiaud, J.; Ghidaglia, J.M.

    2014-01-01

    We present here a model for two phase flows which is simpler than the 6-equations models (with two densities, two velocities, two temperatures) but more accurate than the standard mixture models with 4 equations (with two densities, one velocity and one temperature). We are interested in the case when the two-phases have been interacting long enough for the drag force to be small but still not negligible. The so-called Homogeneous Equilibrium Mixture Model (HEM) that we present is dealing with both mixture and relative quantities, allowing in particular to follow both a mixture velocity and a relative velocity. This relative velocity is not tracked by a conservation law but by a closure law (drift relation), whose expression is related to the drag force terms of the two-phase flow. After the derivation of the model, a stability analysis and numerical experiments are presented. (authors)

  10. Adiabatic equilibrium models for direct containment heating

    International Nuclear Information System (INIS)

    Pilch, M.; Allen, M.D.

    1991-01-01

    Probabilistic risk assessment (PRA) studies are being extended to include a wider spectrum of reactor plants than was considered in NUREG-1150. There is a need for simple direct containment heating (DCH) models that can be used for screening studies aimed at identifying potentially significant contributors to overall risk in individual nuclear power plants. This paper presents two adiabatic equilibrium models suitable for the task. The first, a single-cell model, places a true upper bound on DCH loads. This upper bound, however, often far exceeds reasonable expectations of containment loads based on CONTAIN calculations and experiment observations. In this paper, a two cell model is developed that captures the major mitigating feature of containment compartmentalization, thus providing more reasonable estimates of the containment load

  11. Evaluating equilibrium and non-equilibrium transport of bromide and isoproturon in disturbed and undisturbed soil columns

    Science.gov (United States)

    Dousset, S.; Thevenot, M.; Pot, V.; Šimunek, J.; Andreux, F.

    2007-12-01

    In this study, displacement experiments of isoproturon were conducted in disturbed and undisturbed columns of a silty clay loam soil under similar rainfall intensities. Solute transport occurred under saturated conditions in the undisturbed soil and under unsaturated conditions in the sieved soil because of a greater bulk density of the compacted undisturbed soil compared to the sieved soil. The objective of this work was to determine transport characteristics of isoproturon relative to bromide tracer. Triplicate column experiments were performed with sieved (structure partially destroyed to simulate conventional tillage) and undisturbed (structure preserved) soils. Bromide experimental breakthrough curves were analyzed using convective-dispersive and dual-permeability (DP) models (HYDRUS-1D). Isoproturon breakthrough curves (BTCs) were analyzed using the DP model that considered either chemical equilibrium or non-equilibrium transport. The DP model described the bromide elution curves of the sieved soil columns well, whereas it overestimated the tailing of the bromide BTCs of the undisturbed soil columns. A higher degree of physical non-equilibrium was found in the undisturbed soil, where 56% of total water was contained in the slow-flow matrix, compared to 26% in the sieved soil. Isoproturon BTCs were best described in both sieved and undisturbed soil columns using the DP model combined with the chemical non-equilibrium. Higher degradation rates were obtained in the transport experiments than in batch studies, for both soils. This was likely caused by hysteresis in sorption of isoproturon. However, it cannot be ruled out that higher degradation rates were due, at least in part, to the adopted first-order model. Results showed that for similar rainfall intensity, physical and chemical non-equilibrium were greater in the saturated undisturbed soil than in the unsaturated sieved soil. Results also suggested faster transport of isoproturon in the undisturbed soil due

  12. Are the Concepts of Dynamic Equilibrium and the Thermodynamic Criteria for Spontaneity, Nonspontaneity, and Equilibrium Compatible?

    Science.gov (United States)

    Silverberg, Lee J.; Raff, Lionel M.

    2015-01-01

    Thermodynamic spontaneity-equilibrium criteria require that in a single-reaction system, reactions in either the forward or reverse direction at equilibrium be nonspontaneous. Conversely, the concept of dynamic equilibrium holds that forward and reverse reactions both occur at equal rates at equilibrium to the extent allowed by kinetic…

  13. Approach to transverse equilibrium in axial channeling

    International Nuclear Information System (INIS)

    Fearick, R.W.

    2000-01-01

    Analytical treatments of channeling rely on the assumption of equilibrium on the transverse energy shell. The approach to equilibrium, and the nature of the equilibrium achieved, is examined using solutions of the equations of motion in the continuum multi-string model. The results show that the motion is chaotic in the absence of dissipative processes, and a complicated structure develops in phase space which prevent the development of the simple equilibrium usually assumed. The role of multiple scattering in smoothing out the equilibrium distribution is investigated

  14. Pulmonary hypertenstion ad leading factor in patients undergoing dialysis

    International Nuclear Information System (INIS)

    Rehman, I.U.; Sumera, A.; Idrees, M.K.; Tanweer, A.

    2014-01-01

    Objective: To determine the frequency and leading factors of pulmonary hypertension among chronic hemodialysis patients. Study Design: Case series. Place and Duration of Study: Hemodialysis Unit, Department of Nephrology, Sindh Institute of Urology and Transplantation, Karachi, from September 2011 to March 2012. Methodology: Patients of either gender aged between 16 to 60 years of age undergoing hemodialysis for at least 3 months not having pre-existing valvular heart disease, chronic lung disease or connective tissue disorder were included. Pulmonary hypertension was prospectively estimated by Doppler echocardiogram on patients undergoing dialysis. Pulmonary artery pressure was calculated on the post-dialysis day and leading factors were compared between patients with and without pulmonary hypertension. Results: A total of 178 patients were included in study with male to female ratio120/58 (2.06:1). The mean age was 33.84 +- 11.9 years. The mean duration of hemodialysis was 23.85 +- 22.48 months. Pulmonary hypertension was found in 76 (42.7%) patients. Out of the studied factors, low serum albumin ( 3.4 mg/dl, p = 0.01) was found to be statistically significant in patients with pulmonary hypertension. Conclusion: Pulmonary hypertension was frequently present in dialysis population (42.7%). This subset of patients had significantly lower albumin levels in serum. More research is needed in its pathogenesis to arrest its course. (author)

  15. Serum sodium and mortality in a national peritoneal dialysis cohort.

    Science.gov (United States)

    Ravel, Vanessa A; Streja, Elani; Mehrotra, Rajnish; Sim, John J; Harley, Kevin; Ayus, Juan Carlos; Amin, Alpesh N; Brunelli, Steven M; Kovesdy, Csaba P; Kalantar-Zadeh, Kamyar; Rhee, Connie M

    2017-07-01

    Sodium disarrays are common in peritoneal dialysis (PD) patients, and may be associated with adverse outcomes in this population. However, few studies of limited sample size have examined the association of serum sodium with mortality in PD patients, with inconsistent results. We hypothesized that both hypo- and hypernatremia are associated with higher death risk in a nationally representative cohort of US PD patients. We sought to examine the association of serum sodium over time and mortality among 4687 adult incident PD patients from a large US dialysis organization who underwent one or more serum sodium measurements within the first 3 months of dialysis over January 2007 to December 2011. We examined the association of time-dependent and baseline sodium with all-cause mortality as a proxy of short- and long-term sodium-mortality associations, respectively. Hazard ratios were estimated using Cox models with three adjustment levels: minimally adjusted, case-mix adjusted, and case-mix + laboratory adjusted. In time-dependent analyses, sodium levels mortality remained significant for levels mortality risk across all models (ref: 140 to <142 mEq/L). In PD patients, lower time-dependent and baseline sodium levels were independently associated with higher death risk. Further studies are needed to determine whether correction of dysnatremia improves longevity in this population. © The Author 2016. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

  16. Predictive Modelling Risk Calculators and the Non Dialysis Pathway.

    Science.gov (United States)

    Robins, Jennifer; Katz, Ivor

    2013-04-16

    This guideline will review the current prediction models and survival/mortality scores available for decision making in patients with advanced kidney disease who are being considered for a non-dialysis treatment pathway. Risk prediction is gaining increasing attention with emerging literature suggesting improved patient outcomes through individualised risk prediction (1). Predictive models help inform the nephrologist and the renal palliative care specialists in their discussions with patients and families about suitability or otherwise of dialysis. Clinical decision making in the care of end stage kidney disease (ESKD) patients on a non-dialysis treatment pathway is currently governed by several observational trials (3). Despite the paucity of evidence based medicine in this field, it is becoming evident that the survival advantages associated with renal replacement therapy in these often elderly patients with multiple co-morbidities and limited functional status may be negated by loss of quality of life (7) (6), further functional decline (5, 8), increased complications and hospitalisations. This article is protected by copyright. All rights reserved.

  17. Self-management support for peritoneal dialysis patients.

    Science.gov (United States)

    Sarian, Mari; Brault, Diane; Perreault, Nathalie

    2012-01-01

    The increasing prevalence of chronic illnesses and kidney disease, in particular, makes it necessary to adopt new approaches towards their management (Wagner, 1998). Evidence suggests that promoting self-management improves the health status of peritoneal dialysis (PD) patients, as they manage upwards of 90% of their own care. Patients who are unable to self-manage suffer from various complications. This project proposes an intervention aimed at improving self-management skills among PD patients. To promote self-management in peritoneal dialysis patients. This is achieved through the following objectives: (a) develop an algorithm that can improve patients' ability to solve the specific problem of fluid balance maintenance, (b) develop an educational session for patients on how to use the algorithm, and (c) develop an implementation strategy in collaboration with the PD nurse. Three measures evaluate the effectiveness of the intervention. First, a telephone call log shows that participating patients call the clinic less to inquire about fluid balance maintenance. Next, a pre- and post-intervention knowledge test measures definite knowledge increase. Finally, a Patient Satisfaction Questionnaire reveals overall satisfaction with the intervention. This project, which proved beneficial to our patient population, could be duplicated in other clinics. The algorithm "How do I choose a dialysis bag" and the slides of the educational sessions can be shared with PD nurses across the country for the benefit of PD patients.

  18. DIALYSIS SERVICES’ INFECTED WASTE: A DISCUSSION ABOUT ITS MANAGEMENT

    Directory of Open Access Journals (Sweden)

    Izilda Simões Vitorino Eliam

    2006-12-01

    Full Text Available ABSTRACT: Professionals of the dialysis services face risky situations since from the accomplishment of the pratical procedures to the management of the different kinds of waste generated in these services. Accidents with needlestick materials represent one of the biggest risks for workers of the health. The objective was to characterize the management of infected waste in the dialysis services in Goiânia - GO. This is a descriptive study, with data collected in 2004, march, by check list elaborated accordancing to RDC 33/ 03/ANVISA, previously validated, with ethical and legal aspects observed and legal allowance of the eleven services. It was clearly shown that the discharging of needlestick materials is done specific by four units of service; seven services improvise the container, using bottles of dialysis solution, in order to deischarge the materials. In eight services milky white bags were used to discharge the dialysers. The segregation of the needlestick material waste does happen next to the generating source in the majority of the units (91%. The majority of the units didn’t have dustbin for infected waste with covers in motion for pedal. The internal transport is made manually in 82% of the services. This study concluded that in the majority of the researched services, the management of the waste does not follow the biosecurity rules, increasing the collective biological risk. KEYWORDS: Medical Waste; Hospital Hemodialysis Units; Enviroment.

  19. Residual Renal Function in Children Treated with Chronic Peritoneal Dialysis

    Directory of Open Access Journals (Sweden)

    Maria Roszkowska-Blaim

    2013-01-01

    Full Text Available Residual renal function (RRF in patients with end-stage renal disease (ESRD receiving renal replacement therapy is defined as the ability of native kidneys to eliminate water and uremic toxins. Preserved RRF improves survival and quality of life in adult ESRD patients treated with peritoneal dialysis. In children, RRF was shown not only to help preserve adequacy of renal replacement therapy but also to accelerate growth rate, improve nutrition and blood pressure control, reduce the risk of adverse myocardial changes, facilitate treatment of anemia and calcium-phosphorus balance abnormalities, and result in reduced serum and dialysate fluid levels of advanced glycation end-products. Factors contributing to RRF loss in children treated with peritoneal dialysis include the underlying renal disease such as hemolytic-uremic syndrome and hereditary nephropathy, small urine volume, severe proteinuria at the initiation of renal replacement therapy, and hypertension. Several approaches can be suggested to decrease the rate of RRF loss in pediatric patients treated with chronic peritoneal dialysis: potentially nephrotoxic drugs (e.g., aminoglycosides, episodes of hypotension, and uncontrolled hypertension should be avoided, urinary tract infections should be treated promptly, and loop diuretics may be used to increase salt and water excretion.

  20. Adherence of pediatric patients to automated peritoneal dialysis.

    Science.gov (United States)

    Chua, Annabelle N; Warady, Bradley A

    2011-05-01

    Little information is available on adherence to a home automated peritoneal dialysis (APD) prescription for children with end-stage renal disease. We have therefore retrospectively reviewed HomeChoice PRO Card data from patients Adherence was characterized as occurring ≥ 95%, 90-94%, or treatment adherence and patient age, gender, race and if the patient had received training, respectively, was assessed. Of the 51 patients (57% male), with a mean age at peritoneal dialysis (PD) onset of 11.8 ± 5.3 years, 28 (55%) were adherent for all variables. No difference in mean age or if patients were trained existed between the two groups. Males were more likely to be non-adherent (p = 0.026) as were African Americans (p = 0.048). The majority of patients were adherent to duration (96%) and number of cycles (92%), whereas non-adherence was more common with number of sessions (82%) and dialysate volume (78%). In conclusion, 45% of the pediatric patients in our study cohort exhibited some non-adherence to their prescribed APD regimen, emphasizing the value of closely monitoring the performance of home dialysis in children.

  1. Pleuroperitoneal leak complicating peritoneal dialysis: a case series.

    LENUS (Irish Health Repository)

    Kennedy, C

    2012-02-01

    Pressure related complications such as abdominal wall hernias occur with relative frequency in patients on peritoneal dialysis. Less frequently, a transudative pleural effusion containing dialysate can develop. This phenomenon appears to be due to increased intra-abdominal pressure in the setting of congenital or acquired diaphragmatic defects. We report three cases of pleuroperitoneal leak that occurred within a nine-month period at our institution. We review the literature on this topic, and discuss management options. The pleural effusion resolved in one patient following drainage of the peritoneum and a switch to haemodialysis. One patient required emergency thoracocentesis. The third patient developed a complex effusion requiring surgical intervention. The three cases highlight the variability of this condition in terms of timing, symptoms and management. The diagnosis of a pleuroperitoneal leak is an important one as it is managed very differently to most transudative pleural effusions seen in this patient population. Surgical repair may be necessary in those patients who wish to resume peritoneal dialysis, or in those patients with complex effusions. Pleuroperitoneal leak should be considered in the differential diagnosis of a pleural effusion, particularly a right-sided effusion, in a patient on peritoneal dialysis.

  2. [Diverticular disease of the colon in peritoneal dialysis].

    Science.gov (United States)

    Buemi, M; Aloisi, C; Romeo, A; Sturiale, A; Barilla', A; Cosentini, V; Aloisi, E; Corica, F; Ruello, A; Frisina, N

    2002-01-01

    Colon diverticular disease is a very common pathology in western countries and represents a risk factor for septic-type complications, especially in peritoneal dialysis patients. We examined both diagnostic procedure and therapeutics options, either pharmacological or surgical. Ultrasonography, which is useful for the diagnosis of diverticulosis and diverticular disease, has been supported in the last few years by new imaging techniques, such as NMR and CT, that also find applications in the treatment of diverticulitis complications like peritoneal abscesses. Our emphasis is on the therapeutic perspective, either dietetic - based on the use of a fibre-rich diet and the infusion of liquids by intravenous injection - or surgical, such as the Hartmann procedure, single anastomosis with stomia conservation and laparoscopic and endoscopic treatment. These therapeutic approaches have reduced both morbidity and mortality rate and have emphasized how the reduction of surgical stress on the mesothelium promotes the recovery of the functional integrity and, consequently, faster resumption of peritoneal dialysis. In conclusion, diverticulosis alone is not a contraindication for peritoneal dialysis, but constitutes a risk factor for the continuation of this alternative treatment.

  3. A simulation model to estimate the cost and effectiveness of alternative dialysis initiation strategies.

    Science.gov (United States)

    Lee, Chris P; Chertow, Glenn M; Zenios, Stefanos A

    2006-01-01

    Patients with end-stage renal disease (ESRD) require dialysis to maintain survival. The optimal timing of dialysis initiation in terms of cost-effectiveness has not been established. We developed a simulation model of individuals progressing towards ESRD and requiring dialysis. It can be used to analyze dialysis strategies and scenarios. It was embedded in an optimization frame worked to derive improved strategies. Actual (historical) and simulated survival curves and hospitalization rates were virtually indistinguishable. The model overestimated transplantation costs (10%) but it was related to confounding by Medicare coverage. To assess the model's robustness, we examined several dialysis strategies while input parameters were perturbed. Under all 38 scenarios, relative rankings remained unchanged. An improved policy for a hypothetical patient was derived using an optimization algorithm. The model produces reliable results and is robust. It enables the cost-effectiveness analysis of dialysis strategies.

  4. Impact of facility size and profit status on intermediate outcomes in chronic dialysis patients.

    Science.gov (United States)

    Frankenfield, D L; Sugarman, J R; Presley, R J; Helgerson, S D; Rocco, M V

    2000-08-01

    Little information is available regarding the influence of dialysis facility size or profit status on intermediate outcomes in chronic dialysis patients. We have combined data from the Health Care Financing Administration (HCFA) Core Indicators Project; the end-stage renal disease (ESRD) facility survey; and the HCFA On-Line Survey, Certification, and Reporting System to analyze trends in this area. For hemodialysis patients, larger facilities were more likely than smaller facilities to perform dialysis on patients who were younger than 65 years of age, black, or undergoing dialysis 2 years or more (P profit units (P reduction ratio, but not with hematocrit or serum albumin values. Facility profit status was not associated with these intermediate outcomes. For peritoneal dialysis patients, there were no significant differences in patient demographics based on facility size. More patients in nonprofit units had been undergoing dialysis 2 or more years than patients in for-profit units (P profit status.

  5. Fluorescence lifetime components reveal kinetic intermediate states upon equilibrium denaturation of carbonic anhydrase II.

    Science.gov (United States)

    Nemtseva, Elena V; Lashchuk, Olesya O; Gerasimova, Marina A; Melnik, Tatiana N; Nagibina, Galina S; Melnik, Bogdan S

    2017-12-21

    In most cases, intermediate states of multistage folding proteins are not 'visible' under equilibrium conditions but are revealed in kinetic experiments. Time-resolved fluorescence spectroscopy was used in equilibrium denaturation studies. The technique allows for detecting changes in the conformation and environment of tryptophan residues in different structural elements of carbonic anhydrase II which in its turn has made it possible to study the intermediate states of carbonic anhydrase II under equilibrium conditions. The results of equilibrium and kinetic experiments using wild-type bovine carbonic anhydrase II and its mutant form with the substitution of leucine for alanine at position 139 (L139A) were compared. The obtained lifetime components of intrinsic tryptophan fluorescence allowed for revealing that, the same as in kinetic experiments, under equilibrium conditions the unfolding of carbonic anhydrase II ensues through formation of intermediate states.

  6. Influence of various room parameters upon radon daughter equilibrium indoors

    International Nuclear Information System (INIS)

    Islam, G.S.; Mazumdar, S.C.; Ashraf, M.A.

    1995-06-01

    The parameters such as ventilation rate, attachment rate to aerosols and deposition processes, which influence the radon daughter equilibrium indoors, are discussed and the validity of the theoretical model checked by experiments. In agreement with the model calculations, the experimental data show, that the equilibrium factor F in rooms is mainly influenced by the rate of attachment to aerosols and the plateout of radon daughters. The equilibrium factor varies between 0.3 and 0.4 at an attachment rate of 300 h -1 . The influence of ventilation upon the free fraction of RaA( 218 Pp)-atoms is also investigated. This is in good agreement with the results of the measurements carried out in different types of rooms at the University Campus of Rajshahi. (author). 20 refs, 3 figs, 3 tabs

  7. Phase equilibrium data for the ternary system (propane + chloroform + oryzanol)

    International Nuclear Information System (INIS)

    Correa, Fernanda V.; Comim, Sibele R.R.; Cesaro, Aline M. de; Rigo, Aline A.; Mazutti, Marcio A.; Hense, Haiko; Oliveira, J. Vladimir

    2011-01-01

    The compound oryzanol available in the rice bran (oriza sativa) is well known for its antioxidant activity. Phase equilibrium data involving oryzanol in compressed fluids, hardly found in the literature, are important to provide the basis for the extraction and fractionation processes. In this sense, the aim of this work is to report phase equilibrium measurements for the system (γ-oryzanol + chloroform) in compressed propane. Phase equilibrium experiments were performed using the static synthetic method (cloud points transition data) in a high-pressure variable-volume view cell in the temperature range of 303 K to 353 K, pressures up to 17 MPa, for oryzanol overall mass fractions of 2 wt%, 5 wt% and 10 wt% in (propane + chloroform) mixtures. A complex phase behaviour comprising vapour-liquid, liquid-liquid, vapour-liquid-liquid, solid-liquid, solid-liquid-liquid, solid-liquid-liquid-vapour transitions were visually observed for the system studied.

  8. Phase equilibrium data for the ternary system (propane + chloroform + oryzanol)

    Energy Technology Data Exchange (ETDEWEB)

    Correa, Fernanda V.; Comim, Sibele R.R. [EQA/UFSC, Chemical and Food Engineering Department, Federal University of Santa Catarina, C.P. 476, CEP 88040-900, Florianopolis, SC (Brazil); Cesaro, Aline M. de; Rigo, Aline A.; Mazutti, Marcio A. [Department of Food Engineering, URI - Campus de Erechim, Av. Sete de Setembro, 1621, 99700-000 Erechim, RS (Brazil); Hense, Haiko [EQA/UFSC, Chemical and Food Engineering Department, Federal University of Santa Catarina, C.P. 476, CEP 88040-900, Florianopolis, SC (Brazil); Oliveira, J. Vladimir, E-mail: vladimir@uricer.edu.b [Department of Food Engineering, URI - Campus de Erechim, Av. Sete de Setembro, 1621, 99700-000 Erechim, RS (Brazil)

    2011-01-15

    The compound oryzanol available in the rice bran (oriza sativa) is well known for its antioxidant activity. Phase equilibrium data involving oryzanol in compressed fluids, hardly found in the literature, are important to provide the basis for the extraction and fractionation processes. In this sense, the aim of this work is to report phase equilibrium measurements for the system ({gamma}-oryzanol + chloroform) in compressed propane. Phase equilibrium experiments were performed using the static synthetic method (cloud points transition data) in a high-pressure variable-volume view cell in the temperature range of 303 K to 353 K, pressures up to 17 MPa, for oryzanol overall mass fractions of 2 wt%, 5 wt% and 10 wt% in (propane + chloroform) mixtures. A complex phase behaviour comprising vapour-liquid, liquid-liquid, vapour-liquid-liquid, solid-liquid, solid-liquid-liquid, solid-liquid-liquid-vapour transitions were visually observed for the system studied.

  9. Co-gasification of biomass and plastics: pyrolysis kinetics studies, experiments on 100 kW dual fluidized bed pilot plant and development of thermodynamic equilibrium model and balances.

    Science.gov (United States)

    Narobe, M; Golob, J; Klinar, D; Francetič, V; Likozar, B

    2014-06-01

    Thermo-gravimetric analysis (TGA) of volatilization reaction kinetics for 50 wt.% mixtures of plastics (PE) and biomass (wood pellets) as well as for 100 wt.% plastics was conducted to predict decomposition times at 850°C and 900°C using iso-conversional model method. For mixtures, agreement with residence time of dual fluidized bed (DFB) reactor, treated as continuous stirred-tank reactor (CSTR), was obtained at large conversions. Mono-gasification of plastics and its co-gasification with biomass were performed in DFB pilot plant, using olivine as heterogeneous catalyst and heat transfer agent. It was found that co-gasification led to successful thermochemical conversion of plastics as opposed to mono-gasification. Unknown flow rates were determined applying nonlinear regression to energy and mass balances acknowledging combustion fuel, air, steam, feedstock, but also exiting char, tar, steam and other components in DFB gasification unit. Water-gas shift equilibrium and methanol synthesis requirements were incorporated into gasification model, based on measurements. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Full protein alimentation and nitrogen equilibrium in a renal failure patient treated with continuous hemodiafiltration: a case report of 67 days of continuous hemodiafiltration.

    Science.gov (United States)

    Reynolds, H N; Borg, U; Frankenfield, D

    1992-01-01

    Standard care for patients with renal failure while in an intensive care unit involves traditional hemodialysis or peritoneal dialysis and protein restriction. We present a case of a patient with renal failure supported with continuous arteriovenous hemofiltration with dialysis (CAVH-D) who was given full protein alimentation. Total daily urea clearance was measured from the CAVH-D output. Protein load was 196 +/- 34 g/day while receiving total parenteral nutrition and 164 +/- 30 g/day while receiving enteral alimentation. Serum blood urea nitrogen was controlled between 40 and 75 mg/dL, except during septic episodes. Nitrogen balance was estimated based upon known alimentation protein load and measurable and estimated nitrogenous losses. The patient was potentially in nitrogen equilibrium during most of the dialysis period. The cumulative nitrogen balance was positive by 5.2 g after 67 days of dialysis. Volume of alimentation was 3.49 +/- 0.7 liters/day. With CAVH-D, the renal failure patient can receive full alimentation without volume or protein load limitations. Furthermore, nitrogen balances can be estimated easily while the patient is on CAVH-D.

  11. Renal Replacement Therapy: Purifying Efficiency of Automated Peritoneal Dialysis in Diabetic versus Non-Diabetic Patients

    Directory of Open Access Journals (Sweden)

    Nicanor Vega-Diaz

    2015-07-01

    Full Text Available Background: In order to reduce the cardiovascular risk, morbidity and mortality of peritoneal dialysis (PD, a minimal level of small-solute clearances as well as a sodium and water balance are needed. The peritoneal dialysis solutions used in combination have reduced the complications and allow for a long-time function of the peritoneal membrane, and the preservation of residual renal function (RRF in patients on peritoneal dialysis (PD is crucial for the maintenance of life quality and long-term survival. This retrospective cohort study reviews our experience in automatic peritoneal dialysis (APD patients, with end-stage renal disease (ESRD secondary to diabetic nephropathy (DN in comparison to non-diabetic nephropathy (NDN, using different PD solutions in combination. Design: Fifty-two patients, 29 diabetic and 23 non-diabetic, were included. The follow-up period was 24 months, thus serving as their own control. Results: The fraction of renal urea clearance (Kt relative to distribution volume (V (or total body water (Kt/V, or creatinine clearance relative to the total Kt/V or creatinine clearance (CrCl decreases according to loss of RRF. The loss of the slope of RRF is more pronounced in DN than in NDN patients, especially at baseline time interval to 12 months (loss of 0.29 mL/month vs. 0.13 mL/month, respectively, and is attenuated in the range from 12 to 24 months (loss of 0.13 mL/month vs. 0.09 mL/month, respectively. Diabetic patients also experienced a greater decrease in urine output compared to non-diabetic, starting from a higher baseline urine output. The net water balance was adequate in both groups during the follow up period. Regarding the balance sodium, no inter-group differences in sodium excretion over follow up period was observed. In addition, the removal of sodium in the urine output decreases with loss of renal function. The average concentration of glucose increase in the cycler in both groups (DN: baseline 1.44 ± 0

  12. Pre-equilibrium plasma dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Heinz, U.

    1986-01-01

    Approaches towards understanding and describing the pre-equilibrium stage of quark-gluon plasma formation in heavy-ion collisions are reviewed. Focus is on a kinetic theory approach to non-equilibrium dynamics, its extension to include the dynamics of color degrees of freedom when applied to the quark-gluon plasma, its quantum field theoretical foundations, and its relationship to both the particle formation stage at the very beginning of the nuclear collision and the hydrodynamic stage at late collision times. The usefulness of this approach to obtain the transport coefficients in the quark-gluon plasma and to derive the collective mode spectrum and damping rates in this phase are discussed. Comments are made on the general difficulty to find appropriated initial conditions to get the kinetic theory started, and a specific model is given that demonstrates that, once given such initial conditions, the system can be followed all the way through into the hydrodynamical regime. 39 refs., 7 figs. (LEW)

  13. Non-equilibrium phase transition

    International Nuclear Information System (INIS)

    Mottola, E.; Cooper, F.M.; Bishop, A.R.; Habib, S.; Kluger, Y.; Jensen, N.G.

    1998-01-01

    This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Non-equilibrium phase transitions play a central role in a very broad range of scientific areas, ranging from nuclear, particle, and astrophysics to condensed matter physics and the material and biological sciences. The aim of this project was to explore the path to a deeper and more fundamental understanding of the common physical principles underlying the complex real time dynamics of phase transitions. The main emphasis was on the development of general theoretical tools to deal with non-equilibrium processes, and of numerical methods robust enough to capture the time-evolving structures that occur in actual experimental situations. Specific applications to Laboratory multidivisional efforts in relativistic heavy-ion physics (transition to a new phase of nuclear matter consisting of a quark-gluon plasma) and layered high-temperature superconductors (critical currents and flux flow at the National High Magnetic Field Laboratory) were undertaken

  14. Pre-equilibrium plasma dynamics

    International Nuclear Information System (INIS)

    Heinz, U.

    1986-01-01

    Approaches towards understanding and describing the pre-equilibrium stage of quark-gluon plasma formation in heavy-ion collisions are reviewed. Focus is on a kinetic theory approach to non-equilibrium dynamics, its extension to include the dynamics of color degrees of freedom when applied to the quark-gluon plasma, its quantum field theoretical foundations, and its relationship to both the particle formation stage at the very beginning of the nuclear collision and the hydrodynamic stage at late collision times. The usefulness of this approach to obtain the transport coefficients in the quark-gluon plasma and to derive the collective mode spectrum and damping rates in this phase are discussed. Comments are made on the general difficulty to find appropriated initial conditions to get the kinetic theory started, and a specific model is given that demonstrates that, once given such initial conditions, the system can be followed all the way through into the hydrodynamical regime. 39 refs., 7 figs

  15. Equilibrium: two-dimensional configurations

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    In Chapter 6, the problem of toroidal force balance is addressed in the simplest, nontrivial two-dimensional geometry, that of an axisymmetric torus. A derivation is presented of the Grad-Shafranov equation, the basic equation describing axisymmetric toroidal equilibrium. The solutions to equations provide a complete description of ideal MHD equilibria: radial pressure balance, toroidal force balance, equilibrium Beta limits, rotational transform, shear, magnetic wall, etc. A wide number of configurations are accurately modeled by the Grad-Shafranov equation. Among them are all types of tokamaks, the spheromak, the reversed field pinch, and toroidal multipoles. An important aspect of the analysis is the use of asymptotic expansions, with an inverse aspect ratio serving as the expansion parameter. In addition, an equation similar to the Grad-Shafranov equation, but for helically symmetric equilibria, is presented. This equation represents the leading-order description low-Beta and high-Beta stellarators, heliacs, and the Elmo bumpy torus. The solutions all correspond to infinitely long straight helices. Bending such a configuration into a torus requires a full three-dimensional calculation and is discussed in Chapter 7

  16. Factors influencing access to education, decision making, and receipt of preferred dialysis modality in unplanned dialysis start patients

    DEFF Research Database (Denmark)

    Machowska, Anna; Alscher, Mark Dominik; Vanga, Satyanarayana Reddy

    2016-01-01

    for patients receiving education, making a decision, and receiving their preferred modality choice in UPS patients following a UPS educational program (UPS-EP). Methods: The Offering Patients Therapy Options in Unplanned Start (OPTiONS) study examined the impact of the implementation of a specific UPS......-EP, including decision support tools and pathway improvement on dialysis modality choice. Linear regression models were used to examine the factors predicting three key steps: referral and receipt of UPS-EP, modality decision making, and actual delivery of preferred modality choice. A simple economic assessment...... was performed to examine the potential benefit of implementing UPS-EP in terms of dialysis costs. Results: The majority of UPS patients could receive UPS-EP (214/270 patients) and were able to make a decision (177/214), although not all patients received their preferred choice (159/177). Regression analysis...

  17. A Colorful Demonstration to Visualize and Inquire into Essential Elements of Chemical Equilibrium

    Science.gov (United States)

    Eilks, Ingo; Gulacar, Ozcan

    2016-01-01

    One of the topics that chemistry teachers have a great challenge introducing is chemical equilibrium. When being introduced to chemical equilibrium, many students have difficulties in understanding that some reactions do not go to completion, as this contrasts most of their supposed prior experiences in chemistry lessons. Students may also…

  18. Equilibrium and stability of a toroidal-sector plasma discharge in an EXTRAP configuration

    International Nuclear Information System (INIS)

    Drake, J.R.

    1982-02-01

    Experimental studies of the equilibrium and stability of a sector of a toroidal EXTRAP plasma discharge have been studied. The high β plasma discharge, which had an Alfven transit time about 0.5 μsec, could be positioned in a stable equilibrium for the 300μsec time scale of the experiment. (author)

  19. EQUILIBRIUM AND KINETIC NITROGEN AND OXYGEN-ISOTOPE FRACTIONATIONS BETWEEN DISSOLVED AND GASEOUS N2O

    NARCIS (Netherlands)

    INOUE, HY; MOOK, WG

    1994-01-01

    Experiments were performed to determine the equilibrium as well as kinetic stable nitrogen and oxygen isotope fractionations between aqueous dissolved and gaseous N2O. The equilibrium fractionations, defined as the ratio of the isotopic abundance ratios (15R and 18R, respectively) of gaseous and

  20. Dynamic Processes of Conceptual Change: Analysis of Constructing Mental Models of Chemical Equilibrium.

    Science.gov (United States)

    Chiu, Mei-Hung; Chou, Chin-Cheng; Liu, Chia-Ju

    2002-01-01

    Investigates students' mental models of chemical equilibrium using dynamic science assessments. Reports that students at various levels have misconceptions about chemical equilibrium. Involves 10th grade students (n=30) in the study doing a series of hands-on chemical experiments. Focuses on the process of constructing mental models, dynamic…