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Sample records for optimize donor selection

  1. Three-dimensional structure discrepancy between HLA alleles for effective prediction of aGVHD severity and optimal selection of recipient-donor pairs: a proof-of-concept study.

    Science.gov (United States)

    Han, Hongxing; Yuan, Fang; Sun, Yuying; Liu, Jinfeng; Liu, Shuguang; Luo, Yuan; Liang, Fei; Liu, Nan; Long, Juan; Zhao, Xiao; Kong, Fanhua; Xi, Yongzhi

    2015-11-24

    The optimal selection of recipient-donor pair and accurate prediction of acute graft-versus-host disease (aGVHD) severity are always the two most crucial works in allogeneic hematopoietic stem cell transplantation (allo-HSCT), which currently rests mostly with HLA compatibility, the most polymorphic loci in the human genome, in clinic. Thus, there is an urgent need for a rapid and reliable quantitative system for optimal recipient-donor pairs selection and accurate prediction of aGVHD severity prior to allo-HSCT. For these reasons, we have developed a new selection/prediction system for optimal recipient-donor selection and effective prediction of aGVHD severity based on HLA three-dimensional (3D) structure modeling (HLA-TDSM) discrepancy, and applied this system in a pilot randomized clinical allo-HSCT study. The 37 patient-donor pairs in the study were typed at low- and high-resolution levels for HLA-A/-B/-DRB1/-DQB1 loci. HLA-TDSM system covering the 10000 alleles in HLA class I and II consists of the revised local and coordinate root-mean-square deviation (RMSD) values for each locus. Its accuracy and reliability were confirmed using stably transfected Hmy2.CIR-HLA-B cells, TCR Vβ gene scan, and antigen-specific alloreactive cytotoxic lymphocytes. Based on the preliminary results, we theoretically defined all HLA acceptable versus unacceptable mismatched alleles. More importantly, HLA-TDSM enabled a successful retrospective verification and prospective prediction for aGVHD severity in a pilot randomized clinical allo-HSCT study of 32 recipient-donor transplant pairs. There was a strong direct correlation between single/total revised RMSD and aGVHD severity (92% in retrospective group vs 95% in prospective group). These results seem to be closely related to the 3D structure discrepancy of mismatched HLA-alleles, but not the number or loci of mismatched HLA-alleles. Our data first provide the proof-of-concept that HLA-TDSM is essential for optimal selection of

  2. Donor selection criteria and procurement

    International Nuclear Information System (INIS)

    Agcaoili, N.R.

    1999-01-01

    Donor selection is one of the most important aspects of tissue banking practice. Without a good donor selection criteria, the results of any effort of trying to preserve tissues will have disastrous outcome for the recipient of these tissues. While with a very good and strict donor selection the Tissue Bank can guarantee safe and effective tissue allografts. There are significant aspects in the history and physical examination of the donor that must be emphasized. A donor exclusion criteria has also been formulated together with a list of all the needed laboratory examinations to eliminate possible diseases that may be transferred from the donor. The methods of procurement of tissue allografts from living and cadaver donors will be described. The limitations and advantages of each will be taken.There are also special restrictions that are important in the practice of removing the tissues from the donors. All the necessary equipment should be ready and the potential risk on the personnel should be known to all doing Tissue Banking

  3. The optimal hormonal replacement modality selection for multiple organ procurement from brain-dead organ donors

    Directory of Open Access Journals (Sweden)

    Mi Z

    2014-12-01

    Full Text Available Zhibao Mi,1 Dimitri Novitzky,2 Joseph F Collins,1 David KC Cooper3 1Cooperative Studies Program Coordinating Center, VA Maryland Health Care Systems, Perry Point, MD, USA; 2Department of Cardiothoracic Surgery, University of South Florida, Tampa, FL, USA; 3Thomas E Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, USA Abstract: The management of brain-dead organ donors is complex. The use of inotropic agents and replacement of depleted hormones (hormonal replacement therapy is crucial for successful multiple organ procurement, yet the optimal hormonal replacement has not been identified, and the statistical adjustment to determine the best selection is not trivial. Traditional pair-wise comparisons between every pair of treatments, and multiple comparisons to all (MCA, are statistically conservative. Hsu’s multiple comparisons with the best (MCB – adapted from the Dunnett’s multiple comparisons with control (MCC – has been used for selecting the best treatment based on continuous variables. We selected the best hormonal replacement modality for successful multiple organ procurement using a two-step approach. First, we estimated the predicted margins by constructing generalized linear models (GLM or generalized linear mixed models (GLMM, and then we applied the multiple comparison methods to identify the best hormonal replacement modality given that the testing of hormonal replacement modalities is independent. Based on 10-year data from the United Network for Organ Sharing (UNOS, among 16 hormonal replacement modalities, and using the 95% simultaneous confidence intervals, we found that the combination of thyroid hormone, a corticosteroid, antidiuretic hormone, and insulin was the best modality for multiple organ procurement for transplantation. Keywords: best treatment selection, brain-dead organ donors, hormonal replacement, multiple binary endpoints, organ procurement, multiple comparisons

  4. How to optimize the lung donor.

    Science.gov (United States)

    Sales, Gabriele; Costamagna, Andrea; Fanelli, Vito; Boffini, Massimo; Pugliese, Francesco; Mascia, Luciana; Brazzi, Luca

    2018-02-01

    Over the last two decades, lung transplantation emerged as the standard of care for patients with advanced and terminal lung disease. Despite the increment in lung transplantation rates, in 2016 the overall mortality while on waiting list in Italy reached 10%, whereas only 39% of the wait-list patients were successfully transplanted. A number of approaches, including protective ventilatory strategy, accurate management of fluid balance, and administration of a hormonal resuscitation therapy, have been reported to improve lung donor performance before organ retrieval. These approaches, in conjunction with the use of ex-vivo lung perfusion technique contributed to expand the lung donor pool, without affecting the harvest of other organs and the outcomes of lung recipients. However, the efficacy of issues related to the ex-vivo lung perfusion technique, such as the optimal ventilation strategy, the ischemia-reperfusion induced lung injury management, the prophylaxis of germs transmission from donor to recipient and the application of targeted pharmacologic therapies to treat specific donor lung injuries are still to be explored. The main objective of the present review is to summarize the "state-of-art" strategies to optimize the donor lungs and to present the actual role of ex-vivo lung perfusion in the process of lung transplant. Moreover, different approaches about the technique reported in literature and several issues that are under investigation to treat specific donor lung injury will be discussed.

  5. Computer-based planning of optimal donor sites for autologous osseous grafts

    Science.gov (United States)

    Krol, Zdzislaw; Chlebiej, Michal; Zerfass, Peter; Zeilhofer, Hans-Florian U.; Sader, Robert; Mikolajczak, Pawel; Keeve, Erwin

    2002-05-01

    Bone graft surgery is often necessary for reconstruction of craniofacial defects after trauma, tumor, infection or congenital malformation. In this operative technique the removed or missing bone segment is filled with a bone graft. The mainstay of the craniofacial reconstruction rests with the replacement of the defected bone by autogeneous bone grafts. To achieve sufficient incorporation of the autograft into the host bone, precise planning and simulation of the surgical intervention is required. The major problem is to determine as accurately as possible the donor site where the graft should be dissected from and to define the shape of the desired transplant. A computer-aided method for semi-automatic selection of optimal donor sites for autografts in craniofacial reconstructive surgery has been developed. The non-automatic step of graft design and constraint setting is followed by a fully automatic procedure to find the best fitting position. In extension to preceding work, a new optimization approach based on the Levenberg-Marquardt method has been implemented and embedded into our computer-based surgical planning system. This new technique enables, once the pre-processing step has been performed, selection of the optimal donor site in time less than one minute. The method has been applied during surgery planning step in more than 20 cases. The postoperative observations have shown that functional results, such as speech and chewing ability as well as restoration of bony continuity were clearly better compared to conventionally planned operations. Moreover, in most cases the duration of the surgical interventions has been distinctly reduced.

  6. The optimal hormonal replacement modality selection for multiple organ procurement from brain-dead organ donors.

    Science.gov (United States)

    Mi, Zhibao; Novitzky, Dimitri; Collins, Joseph F; Cooper, David Kc

    2015-01-01

    The management of brain-dead organ donors is complex. The use of inotropic agents and replacement of depleted hormones (hormonal replacement therapy) is crucial for successful multiple organ procurement, yet the optimal hormonal replacement has not been identified, and the statistical adjustment to determine the best selection is not trivial. Traditional pair-wise comparisons between every pair of treatments, and multiple comparisons to all (MCA), are statistically conservative. Hsu's multiple comparisons with the best (MCB) - adapted from the Dunnett's multiple comparisons with control (MCC) - has been used for selecting the best treatment based on continuous variables. We selected the best hormonal replacement modality for successful multiple organ procurement using a two-step approach. First, we estimated the predicted margins by constructing generalized linear models (GLM) or generalized linear mixed models (GLMM), and then we applied the multiple comparison methods to identify the best hormonal replacement modality given that the testing of hormonal replacement modalities is independent. Based on 10-year data from the United Network for Organ Sharing (UNOS), among 16 hormonal replacement modalities, and using the 95% simultaneous confidence intervals, we found that the combination of thyroid hormone, a corticosteroid, antidiuretic hormone, and insulin was the best modality for multiple organ procurement for transplantation.

  7. Eye bank procedures: donor selection criteria.

    Science.gov (United States)

    Sousa, Sidney Júlio de Faria E; Sousa, Stella Barretto de Faria E

    2018-01-01

    Eye banks use sterile procedures to manipulate the eye, antiseptic measures for ocular surface decontamination, and rigorous criteria for donor selection to minimize the possibility of disease transmission due to corneal grafting. Donor selection focuses on analysis of medical records and specific post-mortem serological tests. To guide and standardize procedures, eye bank associations and government agencies provide lists of absolute and relative contraindications for use of the tissue based on donor health history. These lists are guardians of the Hippocratic principle "primum non nocere." However, each transplantation carries risk of transmission of potentially harmful agents to the recipient. The aim of the procedures is not to eliminate risk, but limit it to a reasonable level. The balance between safety and corneal availability needs to be maintained by exercising prudence without disproportionate rigor.

  8. Challenges in unrelated hematopoietic stem cell transplantation. Access | Donor search and selection | Outcome

    NARCIS (Netherlands)

    Jöris, Monique Maria

    2013-01-01

    The studies described in this thesis are aimed at improving the whole spectrum of unrelated HSCT in order to help as many patients in need of HSCT as possible. It covers three different but related topics; from access to HSCT to optimizing donor search and selection of acceptable mismatches to

  9. Criteria for selecting organ donors and recipients.

    Science.gov (United States)

    Michielsen, P

    1990-11-01

    As there is a world-wide shortage of organs for transplantation, the selection of the patients is more defined by the availability of transplantable organs than by the medical condition of the potential recipient. This shortage of cadaveric organs is mainly responsible for the use of living donors. With HLA identical sibling donors the results are better than with cadaveric organs, but the ethical problems are usually underestimated. For the parent-to-child donation, the HLA compatibility is less than what could be achieved with well-matched cadaveric donors. The use of genetically unrelated donors is unacceptable from the ethical as well as from the medical point of view. The short- and long-term risk of donation has been insufficiently documented. The experience with the introduction of an opting-out legislation in Belgium in 1987 demonstrates that the shortage of cadaveric organs can be overcome. Harmonization of the legislation is, however, necessary so as to achieve comparable organ retrieval rates between countries participating in organ-exchange organisations.

  10. Optimizing donor scheduling before recruitment: An effective approach to increasing apheresis platelet collections.

    Science.gov (United States)

    Lokhandwala, Parvez M; Shike, Hiroko; Wang, Ming; Domen, Ronald E; George, Melissa R

    2018-01-01

    Typical approach for increasing apheresis platelet collections is to recruit new donors. Here, we investigated the effectiveness of an alternative strategy: optimizing donor scheduling, prior to recruitment, at a hospital-based blood donor center. Analysis of collections, during the 89 consecutive months since opening of donor center, was performed. Linear regression and segmented time-series analyses were performed to calculate growth rates of collections and to test for statistical differences, respectively. Pre-intervention donor scheduling capacity was 39/month. In the absence of active donor recruitment, during the first 29 months, the number of collections rose gradually to 24/month (growth-rate of 0.70/month). However, between month-30 and -55, collections exhibited a plateau at 25.6 ± 3.0 (growth-rate of -0.09/month) (pcollection days/week (month-72). Consequently, the scheduling capacity increased to 130/month. Post-interventions, apheresis platelet collections between month-56 and -81 exhibited a spontaneous renewed growth at a rate of 0.62/month (pcollections. Apheresis platelet collections plateau at nearly 2/3rd of the scheduling capacity. Optimizing the scheduling capacity prior to active donor recruitment is an effective strategy to increase platelet collections at a hospital-based donor center.

  11. Impact of HLA diversity on donor selection in organ and stem cell transplantation.

    Science.gov (United States)

    Tiercy, Jean-Marie; Claas, Frans

    2013-01-01

    The human major histocompatibility complex is a multigene system encoding polymorphic human leucocyte antigens (HLA) that present peptides derived from pathogens to the immune system. The high diversity of HLA alleles and haplotypes in the worldwide populations represents a major barrier to organ and allogeneic hematopoietic stem cell transplantation, because HLA incompatibilities are efficiently recognized by T and B lymphocytes. In organ transplantation, pre-transplant anti-HLA antibodies need to be taken into account for organ allocation. Although HLA-incompatible transplants can be performed thanks to immunosuppressive drugs, the de novo production of anti-HLA antibodies still represents a major cause of graft failure. The HLAMatchmaker computer algorithm determines the immunogenicity of HLA mismatches and allows to define HLA antigens that will not induce an antibody response. Because of the much higher stringency of HLA compatibility criteria in stem cell transplantation, the best donor is a HLA genotypically identical sibling. However, more than 50% of the transplants are now performed with hematopoietic stem cells from volunteer donors selected from the international registry. The development of European national registries covering populations with different HLA haplotype frequencies is essential for optimizing donor search algorithms and providing the best chance for European patients to find a fully compatible donor.

  12. Optimal screening and donor management in a public stool bank.

    Science.gov (United States)

    Kazerouni, Abbas; Burgess, James; Burns, Laura J; Wein, Lawrence M

    2015-12-17

    Fecal microbiota transplantation is an effective treatment for recurrent Clostridium difficile infection and is being investigated as a treatment for other microbiota-associated diseases. To facilitate these activities, an international public stool bank has been created, which screens donors and processes stools in a standardized manner. The goal of this research is to use mathematical modeling and analysis to optimize screening and donor management at the stool bank. Compared to the current policy of screening active donors every 60 days before releasing their quarantined stools for sale, costs can be reduced by 10.3 % by increasing the screening frequency to every 36 days. In addition, the stool production rate varies widely across donors, and using donor-specific screening, where higher producers are screened more frequently, also reduces costs, as does introducing an interim (i.e., between consecutive regular tests) stool test for just rotavirus and C. difficile. We also derive a donor release (i.e., into the system) policy that allows the supply to approximately match an exponentially increasing deterministic demand. More frequent screening, interim screening for rotavirus and C. difficile, and donor-specific screening, where higher stool producers are screened more frequently, are all cost-reducing measures. If screening costs decrease in the future (e.g., as a result of bringing screening in house), a bottleneck for implementing some of these recommendations may be the reluctance of donors to undergo serum screening more frequently than monthly.

  13. Determine The Factors Affecting The Blood Donors Of Selecting Blood Donor Program Me In Western Province Sri Lanka

    Directory of Open Access Journals (Sweden)

    Perera D. A. K.

    2015-08-01

    Full Text Available Abstract Blood and blood component transfusion is one of the major therapeutic practices throughout the world. National Blood Transfusion Service NBTS in Sri Lanka requires approximately 300000 blood units annually. After initiating mobile donor programme there have been two types of blood donation programs in Sri Lanka since 1980. Since second half of first decade of 21st century Sri Lanka shifted to 100 non-replacement blood transfusion policy. That means whole blood and blood component requirement of NBTS has to be collected through mobile blood donor program and voluntary In-house blood donor program. Therefore the objective of this study was to determine the factors affecting the blood donors of selecting blood donor program in Western province Sri Lanka. Methodology This was a cross sectional descriptive study. The study composed of two components. .First the factors that cause the blood donor to select a blood donor programme second the facility survey of blood banks In-house donation. An interviewer administered questionnaire was used to collect data from a sample of 410 Mobile blood donors. Facility survey was done using a checklist. The dependant variables were the attendance of the blood donors to Mobile blood donation and In-house blood donation. Independent variables included were the factors related to socio demography service quality accessibility availability and intrinsic extrinsic motivation. The analytical statistics applied for testing the association of factors with the blood donor programme was chi-square test. The study has shown some important findings. There was significant association between income level and donating blood. Only 3.3 of In-house blood donor population was female. Majority of In-house population belonged to 30-41 age group. A statistically significant association exists between age and repeat blood donation. The female blood donors tendency of becoming repeat donors was very low. Distance problem and non

  14. Selective extraction of trivalent actinides with hard-soft mixed donor ligands: role of intra-ligand synergism

    International Nuclear Information System (INIS)

    Ghanty, Tapan K.

    2016-01-01

    In recent years, considerable attention has been given to understand the coordination chemistry of trivalent lanthanide (Ln) and actinide (An) with various ligands because of its close link with the nuclear waste management processes. It is well known that lanthanide-actinide separation is a challenging and difficult task because of very similar chemical properties of these two series of ions, which are associated with similar ionic radii and coordination numbers. Recently, we have introduced a new concept, 'intra-ligand synergism', where hard donor atom, such as, oxygen preferentially binds to trivalent actinides (An(III)) as compared to the valence iso-electronic trivalent lanthanides (Ln(III)) in presence of another soft donor centre. In the present work, the conventional concept of selective complexation of actinides with soft donor ligands (either S or N donor) has been modified through exploiting this concept, and thereby the higher selectivity of 1,10-phenanthroline-2,9-dicarboxylamide (PDAM) based ligands, namely PDAM and its isobutyl and decyl derivatives towards Am(III) ion has been predicted theoretically through density functional calculations. Subsequently, several such amide derivatives have been synthesized to optimize the solubility of the ligands in organic phase. Finally, solvent extraction experiments have been carried out to validate the theoretical prediction on the selectivity of oxygen donor ligands towards Am(III) as compared to Eu(III), and a maximum separation factor of about 51 has been achieved experimentally using 2,9-bis(N-decylaminocarbonyl)-1,10-phenanthroline ligand. The separation factor is increased with the decrease in pH, which is very interesting since extraction of the Am 3+ ion is considered to be important under highly acidic conditions from the nuclear waste management point of view. (author)

  15. Graft-versus-leukemia, donor selection for adoptive immunotherapy in mice

    International Nuclear Information System (INIS)

    LeFeber, W.P.; Truitt, R.L.; Rose, W.C.; Bortin, M.M.

    1977-01-01

    The optimal donor for adoptive immunotherapy would exhibit great antitumor reactivity and no antihost reactivity. Immunocompetent cells from 11 strains of mice were tested in vivo for their reactivity against a long-passage AKR acute lymphoblastic leukemia and against immunosuppressed nonleukemic AKR mice. Donor mice were syngeneic, unprimed H-2 compatible, primed H-2 compatible, congenic, or H-2 incompatible with AKR. Bioassays were used to evaluate the relative graft-vs.-leukemia (GvL) reactivity and the relative graft-vs.-host (GvH) reactivity of transplanted bone marrow and lymph-node cells from the panel of donors. No significant GvL reactivity was found when cells from syngeneic, unprimed H-2 compatible, or congenic donors were tested. H-2 compatible donors that were immunized with γ-irradiated AKR leukemic spleen cells showed modest GvL reactivity, but associated with the immunization was a disproportionate increase in acute and delayed GvH mortality. Among the H-2 mismatched donors, mice of the SJL strain appeared to most closely approach the ideal because of least intense GvH reactivity and maximal GvL reactivity. As measured in these experiments there was no correlation between the severity of GvH disease and the efficacy of the GvL reaction; GvL reactivity in unprimed donors was always associated with H-2 incompatibility; disparity between donor and recipient at H-2 did not guarantee an effective GvL reaction; and the increase in GvL reactivity obtained by immunizing H-2 compatible donors was overshadowed by the increase in GvH disease

  16. A perspective on the selection of unrelated donors and cord blood units for transplantation

    Science.gov (United States)

    Spellman, Stephen R.; Eapen, Mary; Logan, Brent R.; Mueller, Carlheinz; Rubinstein, Pablo; Setterholm, Michelle I.; Woolfrey, Ann E.; Confer, Dennis L.; Hurley, Carolyn K.

    2012-01-01

    Selection of a suitable graft for allogeneic hematopoietic stem cell transplantation involves consideration of both donor and recipient characteristics. Of primary importance is sufficient donor-recipient HLA matching to ensure engraftment and acceptable rates of GVHD. In this Perspective, the National Marrow Donor Program and the Center for International Blood and Marrow Transplant Research provide guidelines, based on large studies correlating graft characteristics with clinical transplantation outcomes, on appropriate typing strategies and matching criteria for unrelated adult donor and cord blood graft selection. PMID:22596257

  17. Evaluation of living liver donors using contrast enhanced multidetector CT – The radiologists impact on donor selection

    International Nuclear Information System (INIS)

    Ringe, Kristina Imeen; Ringe, Bastian Paul; Falck, Christian von; Shin, Hoen-oh; Becker, Thomas; Pfister, Eva-Doreen; Wacker, Frank; Ringe, Burckhardt

    2012-01-01

    Living donor liver transplantation (LDLT) is a valuable and legitimate treatment for patients with end-stage liver disease. Computed tomography (CT) has proven to be an important tool in the process of donor evaluation. The purpose of this study was to evaluate the significance of CT in the donor selection process. Between May 1999 and October 2010 170 candidate donors underwent biphasic CT. We retrospectively reviewed the results of the CT and liver volumetry, and assessed reasons for rejection. 89 candidates underwent partial liver resection (52.4%). Based on the results of liver CT and volumetry 22 candidates were excluded as donors (31% of the cases). Reasons included fatty liver (n = 9), vascular anatomical variants (n = 4), incidental finding of hemangioma and focal nodular hyperplasia (n = 1) and small (n = 5) or large for size (n = 5) graft volume. CT based imaging of the liver in combination with dedicated software plays a key role in the process of evaluation of candidates for LDLT. It may account for up to 1/3 of the contraindications for LDLT

  18. Associations of health status with subsequent blood donor behavior-An alternative perspective on the Healthy Donor Effect from Donor InSight

    NARCIS (Netherlands)

    van den Hurk, Katja; Zalpuri, Saurabh; Prinsze, Femmeke J.; Merz, Eva-Maria; de Kort, Wim L. A. M.

    2017-01-01

    In donor health research, the 'Healthy Donor Effect' (HDE) often biases study results and hampers their interpretation. This refers to the fact that donors are a selected 'healthier' subset of a population due to both donor selection procedures and self-selection. Donors with long versus short donor

  19. β-Selective mannosylation with a 4,6-silylene-tethered thiomannosyl donor

    DEFF Research Database (Denmark)

    Heuckendorff, Mads; Bendix, Jesper; Pedersen, Christian Marcus

    2014-01-01

    Mannosylations using the new conformationally restricted donor phenyl 2,3-di-O-benzyl-4,6-O-(di-tert-butylsilylene)-1-thio-α-D-mannopyranoside (6) have been found to be β-selective with a variety of activation conditions. The simplest activation conditions were NIS/TfOH, in which case it is propo......Mannosylations using the new conformationally restricted donor phenyl 2,3-di-O-benzyl-4,6-O-(di-tert-butylsilylene)-1-thio-α-D-mannopyranoside (6) have been found to be β-selective with a variety of activation conditions. The simplest activation conditions were NIS/TfOH, in which case...

  20. EVALUATION, SELECTION AND PREPARATION OF LIVING DONOR FOR PARTIAL LIVER TRANSPLANTATION IN CHILDREN

    Directory of Open Access Journals (Sweden)

    S. V. Gautier

    2015-01-01

    Full Text Available Living donor liver transplantation is a highly effective method to help children with end stage liver diseases. Projected success of operation is largely determined at the stage of selection of potential donor. In our review of the literature is presented historical information, are considered «eastern» and «western» way of development of pediatric living donor liver transplantation, are analyzed the ethical and psychosocial aspects of living donor liver transplantation, and also are set out principles and protocols for evaluation potential donors. In addition, the modern views on volumetry of the potential donor liver and on choice of graft type for transplantation, including for children with low weight are presented. 

  1. Evaluation of living liver donors using contrast enhanced multidetector CT – The radiologists impact on donor selection

    Directory of Open Access Journals (Sweden)

    Ringe Kristina

    2012-07-01

    Full Text Available Abstract Background Living donor liver transplantation (LDLT is a valuable and legitimate treatment for patients with end-stage liver disease. Computed tomography (CT has proven to be an important tool in the process of donor evaluation. The purpose of this study was to evaluate the significance of CT in the donor selection process. Methods Between May 1999 and October 2010 170 candidate donors underwent biphasic CT. We retrospectively reviewed the results of the CT and liver volumetry, and assessed reasons for rejection. Results 89 candidates underwent partial liver resection (52.4%. Based on the results of liver CT and volumetry 22 candidates were excluded as donors (31% of the cases. Reasons included fatty liver (n = 9, vascular anatomical variants (n = 4, incidental finding of hemangioma and focal nodular hyperplasia (n = 1 and small (n = 5 or large for size (n = 5 graft volume. Conclusion CT based imaging of the liver in combination with dedicated software plays a key role in the process of evaluation of candidates for LDLT. It may account for up to 1/3 of the contraindications for LDLT.

  2. Selection of unrelated donors for bone marrow transplantation studied in rhesus monkeys

    International Nuclear Information System (INIS)

    Wagemaker, G.; Bekkum, D.W. van

    Graft versus Host disease (GvHD) remains to be a severe limitation to a more general application of bone marrow transplantation. Clinically acceptable results are restricted to those potential recipients for which a major histocompatibility complex (MHC) identical sibling donor is available. At an average family size of 2 to 3 siblings, the frequency of such donors is not more than approximately 30%. This pre-clinical study in rhesus monkeys is directed at the selection of donors for recipients which lack an MHC identical sibling. (Auth.)

  3. http://www.D-MELD.com, the Italian survival calculator to optimize donor to recipient matching and to identify the unsustainable matches in liver transplantation.

    Science.gov (United States)

    Avolio, Alfonso W; Agnes, Salvatore; Cillo, Umberto; Lirosi, Maria C; Romagnoli, Renato; Baccarani, Umberto; Zamboni, Fausto; Nicolini, Daniele; Donataccio, Matteo; Perrella, Alessandro; Ettorre, Giuseppe M; Romano, Marina; Morelli, Nicola; Vennarecci, Giovanni; de Waure, Chiara; Fagiuoli, Stefano; Burra, Patrizia; Cucchetti, Alessandro

    2012-03-01

    Optimization of donor-recipient match is one of the exciting challenges in liver transplantation. Using algorithms obtained by the Italian D-MELD study (5256 liver transplants, 21 Centers, 2002-2009 period), a web-based survival calculator was developed. The calculator is available online at the URL http://www.D-MELD.com. The access is free. Registration and authentication are required. The website was developed using PHP scripting language on HTML platform and it is hosted by the web provider Aruba.it. For a given donor (expressed by donor age) and for three potential recipients (expressed by values of bilirubin, creatinine, INR, and by recipient age, HCV, HBV, portal thrombosis, re-transplant status), the website calculates the patient survival at 90days, 1year, 3years, and allows the identification of possible unsustainable matches (i.e. donor-recipient matches with predicted patient survival less than 50% at 5 years). This innovative approach allows the selection of the best recipient for each referred donor, avoiding the allocation of a high-risk graft to a high-risk recipient. The use of the D-MELD.com website can help transplant surgeons, hepatologists, and transplant coordinators in everyday practice of matching donors and recipients, by selecting the more appropriate recipient among various candidates with different prognostic factors. © 2012 The Authors. Transplant International © 2012 European Society for Organ Transplantation.

  4. Improving preimplantation genetic diagnosis (PGD) reliability by selection of sperm donor with the most informative haplotype.

    Science.gov (United States)

    Malcov, Mira; Gold, Veronica; Peleg, Sagit; Frumkin, Tsvia; Azem, Foad; Amit, Ami; Ben-Yosef, Dalit; Yaron, Yuval; Reches, Adi; Barda, Shimi; Kleiman, Sandra E; Yogev, Leah; Hauser, Ron

    2017-04-26

    The study is aimed to describe a novel strategy that increases the accuracy and reliability of PGD in patients using sperm donation by pre-selecting the donor whose haplotype does not overlap the carrier's one. A panel of 4-9 informative polymorphic markers, flanking the mutation in carriers of autosomal dominant/X-linked disorders, was tested in DNA of sperm donors before PGD. Whenever the lengths of donors' repeats overlapped those of the women, additional donors' DNA samples were analyzed. The donor that demonstrated the minimal overlapping with the patient was selected for IVF. In 8 out of 17 carriers the markers of the initially chosen donors overlapped the patients' alleles and 2-8 additional sperm donors for each patient were haplotyped. The selection of additional sperm donors increased the number of informative markers and reduced misdiagnosis risk from 6.00% ± 7.48 to 0.48% ±0.68. The PGD results were confirmed and no misdiagnosis was detected. Our study demonstrates that pre-selecting a sperm donor whose haplotype has minimal overlapping with the female's haplotype, is critical for reducing the misdiagnosis risk and ensuring a reliable PGD. This strategy may contribute to prevent the transmission of affected IVF-PGD embryos using a simple and economical procedure. All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. DNA testing of donors was approved by the institutional Helsinki committee (registration number 319-08TLV, 2008). The present study was approved by the institutional Helsinki committee (registration number 0385-13TLV, 2013).

  5. Donor Selection for Allogenic Hemopoietic Stem Cell Transplantation: Clinical and Ethical Considerations

    Directory of Open Access Journals (Sweden)

    Irene Riezzo

    2017-01-01

    Full Text Available Allogenic hematopoietic progenitor cell transplantation (allo-HSCT is an established treatment for many diseases. Stem cells may be obtained from different sources: mobilized peripheral blood stem cells, bone marrow, and umbilical cord blood. The progress in transplantation procedures, the establishment of experienced transplant centres, and the creation of unrelated adult donor registries and cord blood banks gave those without an human leucocyte antigen- (HLA- identical sibling donor the opportunity to find a donor and cord blood units worldwide. HSCT imposes operative cautions so that the entire donation/transplantation procedure is safe for both donors and recipients; it carries with it significant clinical, moral, and ethical concerns, mostly when donors are minors. The following points have been stressed: the donation should be excluded when excessive risks for the donor are reasonable, donors must receive an accurate information regarding eventual adverse events and health burden for the donors themselves, a valid consent is required, and the recipient’s risks must be outweighed by the expected benefits. The issue of conflict of interest, when the same physician has the responsibility for both donor selection and recipient care, is highlighted as well as the need of an adequate insurance protection for all the parties involved.

  6. Engineering the donor selectivity of D-fructose-6-phosphate aldolase for biocatalytic asymmetric cross-aldol additions of glycolaldehyde.

    Science.gov (United States)

    Szekrenyi, Anna; Soler, Anna; Garrabou, Xavier; Guérard-Hélaine, Christine; Parella, Teodor; Joglar, Jesús; Lemaire, Marielle; Bujons, Jordi; Clapés, Pere

    2014-09-22

    D-Fructose-6-phosphate aldolase (FSA) is a unique catalyst for asymmetric cross-aldol additions of glycolaldehyde. A combination of a structure-guided approach of saturation mutagenesis, site-directed mutagenesis, and computational modeling was applied to construct a set of FSA variants that improved the catalytic efficiency towards glycolaldehyde dimerization up to 1800-fold. A combination of mutations in positions L107, A129, and A165 provided a toolbox of FSA variants that expand the synthetic possibilities towards the preparation of aldose-like carbohydrate compounds. The new FSA variants were applied as highly efficient catalysts for cross-aldol additions of glycolaldehyde to N-carbobenzyloxyaminoaldehydes to furnish between 80-98 % aldol adduct under optimized reaction conditions. Donor competition experiments showed high selectivity for glycolaldehyde relative to dihydroxyacetone or hydroxyacetone. These results demonstrate the exceptional malleability of the active site in FSA, which can be remodeled to accept a wide spectrum of donor and acceptor substrates with high efficiency and selectivity. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Single-donor islet transplantation and long-term insulin independence in select patients with type 1 diabetes mellitus.

    Science.gov (United States)

    Al-Adra, David P; Gill, Richdeep S; Imes, Sharleen; O'Gorman, Doug; Kin, Tatsuya; Axford, Sara J; Shi, Xinzhe; Senior, Peter A; Shapiro, A M James

    2014-11-15

    Islet transplantation is a recognized treatment option for select patients with type I diabetes mellitus. However, islet infusions from multiple donors are often required to achieve insulin independence. Ideally, insulin independence would be achieved routinely with only a single donor. Identification of factors associated with insulin independence after single-donor islet transplantation may help to select recipient-donor combinations with the highest probability of success. Subjects undergoing islet transplantation at a single center (Edmonton, Canada) between March 1999 and August 2013 were included. Recipient, donor, and transplant characteristics were collected and compared between recipients who became insulin independent after one islet transplantation and those who did not. Thirty-one patients achieved insulin independence after a single-donor islet transplantation, and 149 did not. Long-term insulin-free survival was not different between the groups. Factors significantly associated with single-donor success included recipient age, insulin requirement at baseline, donor weight, donor body mass index, islet transplant mass, and peritransplant heparin and insulin administration. On multivariate analysis, pretransplantation daily insulin requirements, the use of peritransplantation heparin and insulin infusions, and islet transplant mass remained significant. We have identified clinically relevant differences defining the achievement of insulin independence after single-donor transplantation. Based on these differences, a preoperative insulin requirement of less than 0.6 U/kg per day and receiving more than 5,646 islet equivalents (IEQ)/kg have a sensitivity of 84% and 71% and specificity of 50% and 50%, respectively, for insulin independence after single-donor islet transplantation. With ideal patient selection, this finding could potentially increase single-donor transplantation success and may be especially relevant for presensitized subjects or those who

  8. 42 CFR 482.90 - Condition of participation: Patient and living donor selection.

    Science.gov (United States)

    2010-10-01

    ... selected to receive a transplant, the center must document in the patient's medical record the patient... 42 Public Health 5 2010-10-01 2010-10-01 false Condition of participation: Patient and living... Condition of participation: Patient and living donor selection. The transplant center must use written...

  9. Optimization of IVF pregnancy outcomes with donor spermatozoa.

    Science.gov (United States)

    Wang, Jeff G; Douglas, Nataki C; Prosser, Robert; Kort, Daniel; Choi, Janet M; Sauer, Mark V

    2009-03-01

    To identify risk factors for suboptimal IVF outcomes using insemination with donor spermatozoa and to define a lower threshold that may signal a conversion to fertilization by ICSI rather than insemination. Retrospective, age-matched, case-control study of women undergoing non-donor oocyte IVF cycles using either freshly ejaculated (N=138) or cryopreserved donor spermatozoa (N=69). Associations between method of fertilization, semen sample parameters, and pregnancy rates were analyzed. In vitro fertilization of oocytes with donor spermatozoa by insemination results in equivalent fertilization and pregnancy rates compared to those of freshly ejaculated spermatozoa from men with normal semen analyses when the post-processing motility is greater than or equal to 88%. IVF by insemination with donor spermatozoa when the post-processing motility is less than 88% is associated with a 5-fold reduction in pregnancy rates when compared to those of donor spermatozoa above this motility threshold. When the post-processing donor spermatozoa motility is low, fertilization by ICSI is associated with significantly higher pregnancy rates compared to those of insemination. While ICSI does not need to be categorically instituted when using donor spermatozoa in IVF, patients should be counseled that conversion from insemination to ICSI may be recommended based on low post-processing motility.

  10. Establishment of an oocyte donor program. Donor screening and selection.

    Science.gov (United States)

    Quigley, M M; Collins, R L; Schover, L R

    1991-01-01

    IVF with donated oocytes, followed by embryo placement in the uterus of a recipient who has been primed with exogenous steroids, is a successful treatment for special cases of infertility. Preliminary results indicate that the success rate in this situation is even greater than that usually seen with normal IVF (with placement of the embryos back into the uteri of the women from whom the oocytes were recovered). Although different sources for donated oocytes have been identified, the use of "excess" oocytes from IVF cycles and the attempted collection of oocytes at the time of otherwise indicated pelvic surgery have ethical and practical problems associated with their use. We have herein described the establishment of a successful program relying on anonymous volunteers who go through ovarian stimulation, monitoring, and oocyte recovery procedures solely to donate oocytes. The potential donors go through an exhaustive screening and education process before they are accepted in the program. Psychological evaluation of our potential donors indicated a great degree of turmoil in their backgrounds and a wide variety of motivations for actually participating. Despite the extensive educational and screening process, a substantial percentage of the donors did not complete a donation cycle, having either voluntarily withdrawn or been dropped because of lack of compliance. Further investigation of the psychological aspects of participating in such a program is certainly warranted. The use of donated oocytes to alleviate specific types of infertility is quite successful, but the application of this treatment is likely to be limited by the relative unavailability of suitable oocyte donors.

  11. [Is there an age limit for cadaveric kidney donors currently?].

    Science.gov (United States)

    Cofán Pujol, F; Oppenheimer Salinas, F; Talbot-Wright, R; Carretero González, P

    1996-12-01

    The insufficient number of kidney transplants has gradually raised the age limit to the cadaver kidney donor. The use of grafts harvested from older donors has been debated due to the existing structural and functional changes that might influence renal function and long-term graft survival. The foregoing aspects are discussed herein. The anatomical, histological and functional changes in the kidney associated with ageing are analyzed. The clinical experience with renal grafts from older donors before and after cyclosporine became available are reviewed. The ethical issues on whether grafts from very old donors should be used and who should receive these grafts are discussed. The use of grafts from donors over 60 years old had no significant short and medium term differences in comparison with younger donors in terms of graft survival, although a higher incidence of acute tubular necrosis and poor renal function have been observed. There are no conclusive studies on the long-term effects on graft survival when kidneys from donors aged over 65 are utilized. In our experience, the results achieved with grafts from donors over 70 has been unsatisfactory. The guidelines utilized in the selection of grafts derived from older donors are presented. Grafts from donors aged 60 to 70 may be utilized in renal transplantation following precise selection criteria. Graft survival has been satisfactory, although a higher incidence of acute tubular necrosis and higher creatinine levels have been observed. We do not advocate the use of grafts from donors over 70, except in very exceptional cases. Long-term multicenter studies on grafts from very old donors and trials using alternative immunosuppressor modalities that might permit optimal use of these grafts are warranted.

  12. Management to optimize organ procurement in brain dead donors.

    Science.gov (United States)

    Mascia, L; Mastromauro, I; Viberti, S; Vincenzi, M; Zanello, M

    2009-03-01

    The demand for donor organs continues to exceed the number of organs available for transplantation. Many reasons may account for this discrepancy, such as the lack of consent, the absence of an experienced coordinator team able to solve logistical problems, the use of strict donor criteria, and suboptimal, unstandardized critical care management of potential organ donors. This has resulted in efforts to improve the medical care delivered to potential organ donors, so as to reduce organ shortages, improve organ procurement, and promote graft survival. The physiological changes that follow brain death entail a high incidence of complications jeopardizing potentially transplantable organs. Adverse events include cardiovascular changes, endocrine and metabolic disturbances, and disruption of internal homeostasis. Brain death also upregulates the release of pro-inflammatory molecules. Recent findings support the hypothesis that a preclinical lung injury characterized by an enhanced inflammatory response is present in potential donors and may predispose recipients to an adverse clinical prognosis following lung transplantation. In clinical practice, hypotension, diabetes insipidus, relative hypothermia, and natremia are more common than disseminated intravascular coagulation, cardiac arrhythmias, pulmonary oedema, acute lung injury, and metabolic acidosis. Strategies for the management of organ donors exist and consist of the normalization of donor physiology. Management has been complicated by the recent use of ''marginal'' donors and donors of advanced age or with ''extended'' criteria. Current guidelines suggest that the priority of critical care management for potential organ donors should be shifted from a ''cerebral protective'' strategy to a multimodal strategy aimed to preserve peripheral organ function.

  13. Role of Alternative Donor Allogeneic Transplants in the Therapy of Acute Myeloid Leukemia.

    Science.gov (United States)

    Elmariah, Hany; Pratz, Keith W

    2017-07-01

    Adult acute myeloid leukemia (AML) is often associated with a poor prognosis, with allogeneic transplantation representing the greatest chance of cure for eligible patients. Historically, the preferred donor source is a human leukocyte antigen-matched blood relative, although only approximately 30% of patients have access to such a donor. Alternative donor sources, including matched unrelated donors, umbilical cord blood, and haploidentical related donors, are available for almost every patient and are increasingly being used for patients without a matched related donor. Survival outcomes with these alternative donor sources now approximate those of matched related donor transplants. Given the safety and success of alternative donor transplants, comparative trials are needed to reassess the optimal donor source for patients with AML. This review summarizes the available data on these alternative donor transplants. Further investigation is needed to contemporize donor selection algorithms, but, in the current era, donor availability should no longer preclude a patient's eligibility for an allogeneic blood or marrow transplant. Copyright © 2017 by the National Comprehensive Cancer Network.

  14. All-Polymer Solar Cell Performance Optimized via Systematic Molecular Weight Tuning of Both Donor and Acceptor Polymers.

    Science.gov (United States)

    Zhou, Nanjia; Dudnik, Alexander S; Li, Ting I N G; Manley, Eric F; Aldrich, Thomas J; Guo, Peijun; Liao, Hsueh-Chung; Chen, Zhihua; Chen, Lin X; Chang, Robert P H; Facchetti, Antonio; Olvera de la Cruz, Monica; Marks, Tobin J

    2016-02-03

    The influence of the number-average molecular weight (Mn) on the blend film morphology and photovoltaic performance of all-polymer solar cells (APSCs) fabricated with the donor polymer poly[5-(2-hexyldodecyl)-1,3-thieno[3,4-c]pyrrole-4,6-dione-alt-5,5-(2,5-bis(3-dodecylthiophen-2-yl)thiophene)] (PTPD3T) and acceptor polymer poly{[N,N'-bis(2-octyldodecyl)naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5'-(2,2'-bithiophene)} (P(NDI2OD-T2); N2200) is systematically investigated. The Mn effect analysis of both PTPD3T and N2200 is enabled by implementing a polymerization strategy which produces conjugated polymers with tunable Mns. Experimental and coarse-grain modeling results reveal that systematic Mn variation greatly influences both intrachain and interchain interactions and ultimately the degree of phase separation and morphology evolution. Specifically, increasing Mn for both polymers shrinks blend film domain sizes and enhances donor-acceptor polymer-polymer interfacial areas, affording increased short-circuit current densities (Jsc). However, the greater disorder and intermixed feature proliferation accompanying increasing Mn promotes charge carrier recombination, reducing cell fill factors (FF). The optimized photoactive layers exhibit well-balanced exciton dissociation and charge transport characteristics, ultimately providing solar cells with a 2-fold PCE enhancement versus devices with nonoptimal Mns. Overall, it is shown that proper and precise tuning of both donor and acceptor polymer Mns is critical for optimizing APSC performance. In contrast to reports where maximum power conversion efficiencies (PCEs) are achieved for the highest Mns, the present two-dimensional Mn optimization matrix strategy locates a PCE "sweet spot" at intermediate Mns of both donor and acceptor polymers. This study provides synthetic methodologies to predictably access conjugated polymers with desired Mn and highlights the importance of optimizing Mn for both polymer

  15. Improving health profile of blood donors as a consequence of transfusion safety efforts

    DEFF Research Database (Denmark)

    Edgren, Gustaf; Tran, Trung Nam; Hjalgrim, Henrik

    2007-01-01

    BACKGROUND: Transfusion safety rests heavily on the health of blood donors. Although they are perceived as being healthier than average, little is known about their long-term disease patterns and to which extent the blood banks' continuous efforts to optimize donor selection has resulted...... in improvements. Mortality and cancer incidence among blood donors in Sweden and Denmark was investigated. STUDY DESIGN AND METHODS: All computerized blood bank databases were compiled into one database, which was linked to national population and health data registers. With a retrospective cohort study design, 1......,110,329 blood donors were followed for up to 35 years from first computer-registered blood donation to death, emigration, or December 31, 2002. Standardized mortality and incidence ratios expressed relative risk of death and cancer comparing blood donors to the general population. RESULTS: Blood donors had...

  16. Imaging evaluation of potential donors in living-donor liver transplantation

    International Nuclear Information System (INIS)

    Low, G.; Wiebe, E.; Walji, A.H.; Bigam, D.L.

    2008-01-01

    Liver transplants, originally obtained from deceased donors, can now be harvested from living donors as well. This technique, called living-donor liver transplantation (LDLT), provides an effective alternative means of liver transplantation and is a method of expanding the donor pool in light of the demand and supply imbalance for organ transplants. Imaging plays an important role in LDLT programmes by providing robust evaluation of potential donors to ensure that only anatomically suitable donors with no significant co-existing pathology are selected and that crucial information that allows detailed preoperative planning is available. Imaging evaluation helps to improve the outcome of LDLT for both donors and recipients, by improving the chances of graft survival and reducing the postoperative complication rate. In this review, we describe the history of LDLT and discuss in detail the application of imaging in donor assessment with emphasis on use of modern computed tomography (CT) and magnetic resonance imaging (MRI) techniques

  17. Economic Considerations for Selecting an Amine Donor in Biocatalytic Transamination

    DEFF Research Database (Denmark)

    Tufvesson, Pär; Nordblad, Mathias; Krühne, Ulrich

    2015-01-01

    the process, in particular the choice of amine donor. This paper discusses these constraints and demonstrates, through simple thermodynamic and economic models, the process targets that need to be set and achieved for a process dependent on allowed process costs and quality targets....... in industry. The technology has been demonstrated in a few selected cases, but widespread implementation and for a broader range of target molecules requires a deeper understanding of the underlying thermodynamic as well as economic constraints for the different choices that can be made in designing...

  18. Addition of exogenous cytokines in mixed lymphocyte culture for selecting related donors for bone marrow transplantation

    Directory of Open Access Journals (Sweden)

    Jeane Eliete Laguila Visentainer

    Full Text Available CONTEXT: Mixed lymphocyte culturing has led to conflicting opinions regarding the selection of donors for bone marrow transplantation. The association between a positive mixed lymphocyte culture and the development of graft-versus-host disease (GVHD is unclear. The use of exogenous cytokines in mixed lymphocyte cultures could be an alternative for increasing the sensitivity of culture tests. OBJECTIVE: To increase the sensitivity of mixed lymphocyte cultures between donor and recipient human leukocyte antigen (HLA identical siblings, using exogenous cytokines, in order to predict post-transplantation GVHD and/or rejection. TYPE OF STUDY: Prospective study. SETTING: Bone Marrow Transplantation Unit, Universidade Estadual de Campinas. PARTICIPANTS: Seventeen patients with hematological malignancies and their respective donors selected for bone marrow transplantation procedures. PROCEDURES: Standard and modified mixed lymphocyte culturing by cytokine supplementation was carried out using donor and recipient cells typed for HLA. MAIN MEASUREMENTS: Autologous and allogenic responses in mixed lymphocyte cultures after the addition of IL-4 or IL-2. RESULTS: In comparison with the standard method, average responses in the modified mixed lymphocyte cultures increased by a factor of 2.0 using IL-4 (p < 0.001 and 6.4 using IL-2 (p < 0.001, for autologous donor culture responses. For donor-versus-recipient culture responses, the increase was by a factor of 1.9 using IL-4 (p < 0.001 and 4.1 using IL-2 (p < 0.001. For donor-versus-unrelated culture responses, no significant increase was observed using IL-4, and a mean response inhibition of 20% was observed using IL-2 (p < 0.001. Neither of the cytokines produced a significant difference in the unrelated control versus recipient cell responses. CONCLUSION: IL-4 supplementation was the best for increasing the mixed lymphocyte culture sensitivity. However, IL-4 also increased autologous responses, albeit less

  19. Blood donation and blood donor mortality after adjustment for a healthy donor effect

    DEFF Research Database (Denmark)

    Ullum, Henrik; Rostgaard, Klaus; Kamper-Jørgensen, Mads

    2015-01-01

    BACKGROUND: Studies have repeatedly demonstrated that blood donors experience lower mortality than the general population. While this may suggest a beneficial effect of blood donation, it may also reflect the selection of healthy persons into the donor population. To overcome this bias, we...... investigated the relation between blood donation frequency and mortality within a large cohort of blood donors. In addition, our analyses also took into consideration the effects of presumed health differences linked to donation behavior. STUDY DESIGN AND METHODS: Using the Scandinavian Donation...... and mortality. The magnitude of the association was reduced after adjustment for an estimate of self-selection in the donor population. Our observations indicate that repeated blood donation is not associated with premature death, but cannot be interpreted as conclusive evidence of a beneficial health effect....

  20. What women want in their sperm donor: A study of more than 1000 women's sperm donor selections.

    Science.gov (United States)

    Whyte, Stephen; Torgler, Benno; Harrison, Keith L

    2016-12-01

    Reproductive medicine and commercial sperm banking have facilitated an evolutionary shift in how women are able to choose who fathers their offspring, by notionally expanding women's opportunity set beyond former constraints. This study analyses 1546 individual reservations of semen by women from a private Australian assisted reproductive health facility across a ten year period from 2006 to 2015. Using the time that each sample was available at the facility until reservation, we explore women's preference for particular male characteristics. We find that younger donors, and those who hold a higher formal education compared to those with no academic qualifications are more quickly selected for reservation by women. Both age and education as proxies for resources are at the centre of Parental Investment theory, and our findings further build on this standard evolutionary construct in relation to female mate preferences. Reproductive medicine not only provides women the opportunity to become a parent, where previously they would not have been able to, it also reveals that female preference for resources of their potential mate (sperm donor) remain, even when the notion of paternal investment becomes redundant. These findings build on behavioural science's understanding of large-scale decisions and human behaviour in reproductive medical settings. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Organ allocation in pediatric renal transplants: is there an optimal donor?

    Science.gov (United States)

    Pitt, Susan C; Vachharajani, Neeta; Doyle, Maria B; Lowell, Jeffrey A; Chapman, William C; Anderson, Christopher D; Shenoy, Surendra; Wellen, Jason R

    2013-01-01

    The 2005 revised allocation scheme for pediatric renal transplantation made the decision of whether to transplant an available living-donor (LD) kidney or use a deceased-donor (DD) kidney controversial. The aim of this study was to examine kidney allograft utilization, sensitization, and outcomes of pediatric transplant recipients. Between January 2000 and December 2009, 91 consecutive pediatric kidney recipients (transplanted. The LD (n = 38) and DD (n = 53) groups were similar in age, gender, dialysis status at transplant, warm ischemia time, and overall patient survival. LD recipients were more likely to be Caucasian (92 vs. 69%), receive older allografts (39 ± 10 vs. 23 ± 9 yr), and have fewer human leukocyte antigen (HLA) mismatches (3.3 ± 1.6 vs. 4.4 ± 1.5, p transplant was longer for LD recipients (97%, 91%, 87% vs. DD 89%, 79%, 58%, respectively, p transplant, 17 (33%) DD recipients had an available LD (mean age 40 yr). A greater proportion of all patients were moderately (PRA 21-79%) sensitized post-transplant (p organs was likely due to fewer HLA mismatched in this group. Nonetheless, LD organs appear to provide optimal outcomes in pediatric renal transplants when considering the risk of becoming sensitized post-transplant complicating later use of the LD kidney. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  2. Identification of the optimal donor quality scoring system and measure of early renal function in kidney transplantation.

    LENUS (Irish Health Repository)

    Moore, Jason

    2009-02-27

    The early identification of kidney allografts at risk of later dysfunction has implications for clinical practice. Donor quality scoring systems (preoperative) and measures of early allograft function (first week postoperative) have previously shown practical utility. This study aimed to determine the optimal parameter(s) (preoperative and postoperative) with greatest predictive power for the development of subsequent allograft dysfunction.

  3. Single-donor islet transplantation in type 1 diabetes: patient selection and special considerations

    Directory of Open Access Journals (Sweden)

    Tatum JA

    2017-02-01

    Full Text Available Jacob A Tatum,* Max O Meneveau,* Kenneth L Brayman Department of Surgery, Division of Transplantation, The University of Virginia Health System, Charlottesville, VA, USA *These authors contributed equally to this work. Abstract: Type 1 diabetes mellitus is an autoimmune disorder of the endocrine pancreas that currently affects millions of people in the United States. Although the disease can be managed with exogenous insulin administration, the ultimate cure for the condition lies in restoring a patient’s ability to produce their own insulin. Islet cell allotransplantation provides a means of endogenous insulin production. Though far from perfected, islet transplants are now a proven treatment for type 1 diabetics. However, proper patient selection is critical for achieving optimal outcomes. Given the shortage of transplantable organs, selecting appropriate candidates for whom the procedure will be of greatest benefit is essential. Although many of those who receive islets do not retain insulin independence, grafts do play a significant role in preventing hypoglycemic episodes that can be quite detrimental to quality of life and potentially fatal. Additionally, islet transplant requires lifelong immunosuppression. Antibodies, both preformed and following islet infusion, may play important roles in graft outcomes. Finally, no procedure is without inherent risk and islet transfusions can have serious consequences for recipients’ livers in the form of both vascular and metabolic complications. Therefore, patient-specific factors that should be taken into account before islet transplantation include aims of therapy, sensitization, and potential increased risk for hepatic and portal-venous sequelae. Keywords: islet transplantation, diabetes mellitus type 1, brittle diabetes, single donor, patient

  4. Feature Selection via Chaotic Antlion Optimization.

    Directory of Open Access Journals (Sweden)

    Hossam M Zawbaa

    Full Text Available Selecting a subset of relevant properties from a large set of features that describe a dataset is a challenging machine learning task. In biology, for instance, the advances in the available technologies enable the generation of a very large number of biomarkers that describe the data. Choosing the more informative markers along with performing a high-accuracy classification over the data can be a daunting task, particularly if the data are high dimensional. An often adopted approach is to formulate the feature selection problem as a biobjective optimization problem, with the aim of maximizing the performance of the data analysis model (the quality of the data training fitting while minimizing the number of features used.We propose an optimization approach for the feature selection problem that considers a "chaotic" version of the antlion optimizer method, a nature-inspired algorithm that mimics the hunting mechanism of antlions in nature. The balance between exploration of the search space and exploitation of the best solutions is a challenge in multi-objective optimization. The exploration/exploitation rate is controlled by the parameter I that limits the random walk range of the ants/prey. This variable is increased iteratively in a quasi-linear manner to decrease the exploration rate as the optimization progresses. The quasi-linear decrease in the variable I may lead to immature convergence in some cases and trapping in local minima in other cases. The chaotic system proposed here attempts to improve the tradeoff between exploration and exploitation. The methodology is evaluated using different chaotic maps on a number of feature selection datasets. To ensure generality, we used ten biological datasets, but we also used other types of data from various sources. The results are compared with the particle swarm optimizer and with genetic algorithm variants for feature selection using a set of quality metrics.

  5. Analyzing actual risk in malaria-deferred donors through selective serologic testing.

    Science.gov (United States)

    Nguyen, Megan L; Goff, Tami; Gibble, Joan; Steele, Whitney R; Leiby, David A

    2013-08-01

    Approximately 150,000 US blood donors are deferred annually for travel to malaria-endemic areas. However, the majority do not travel to the high-risk areas of Africa associated with transfusion-transmitted malaria (TTM) but visit low-risk areas such as Mexico. This study tests for Plasmodium infection among malaria-deferred donors, particularly those visiting Mexico. Blood donors deferred for malaria risk (travel, residence, or previous infection) provided blood samples and completed a questionnaire. Plasma was tested for Plasmodium antibodies by enzyme immunoassay (EIA); repeat-reactive (RR) samples were considered positive and tested by real-time polymerase chain reaction (PCR). Accepted donors provided background testing data. During 2005 to 2011, a total of 5610 malaria-deferred donors were tested by EIA, including 5412 travel deferrals. Overall, 88 (1.6%) were EIA RR; none were PCR positive. Forty-nine (55.7%) RR donors previously had malaria irrespective of deferral category, including 34 deferred for travel. Among 1121 travelers to Mexico, 90% visited Quintana Roo (no or very low risk), but just 2.2% visited Oaxaca/Chiapas (moderate or high risk). Only two Mexican travelers tested RR; both previously had malaria not acquired in Mexico. Travel to Mexico represents a large percentage of US donors deferred for malaria risk; however, these donors primarily visit no- or very-low-risk areas. No malaria cases acquired in Mexico were identified thereby supporting previous risk estimates. Consideration should be given to allowing blood donations from U.S. donors who travel to Quintana Roo and other low-risk areas in Mexico. A more effective approach to preventing TTM would be to defer all donors with a history of malaria, even if remote. © 2012 American Association of Blood Banks.

  6. Donor evaluation of extended time 99mTcDTPA renal scintigraphy for added information to guide donor kidney selection: a technologist perspective

    International Nuclear Information System (INIS)

    Kale, Chanchala; Tarsaria, Sunita; Jaiswal, R.; Amrita; Roshni; Pallavi

    2010-01-01

    Full text: 99m Tc-DTPA renal scan exposes the patient to considerably less radiation and the images are of superior quality. In donor patients a short time renal scintigraphy to calculate GFR by gates formula is widely accepted in clinical practice. Apart from kidney GFR, renal scan gives added information regarding size, shape and position of kidney, perfusion, peaking time, peak to T 1/2 ratio, transit time, perfusion, split function, assessment of drainage pattern. Aim: The purpose of this study was to evaluate significance of extended time 99m Tc DTPA renogram for appropriate selection of donor kidney. Materials and Method: A retrospective study on 66 patients (female-40, male-26, age range - 22-70 years, mean 48±24) was carried out in our centre. Patients were adequately hydrated before the study. Diuretic intervention renal dynamic scintigraphy (F+10) was performed after administering 5mCi of DTPA intravenously. Sequential dynamic images (Phase I-2 sec/frame for 1 min, Phase II-1 min/frame for 29 min) were acquired posteriorly on GE Millennium VG gamma camera. Pre and post syringe counts were also taken. Standard protocol was used for processing. Along with other parameters GFR by Gates formula was obtained Result: GFR was found to be in the range of 68.7 ml/min - 135.8 ml/min. (mean GFR = 102.25 ml/min). It was found that in 50 patients (75%) both Kidney GFR was normal. Whereas in 2 patients (3.0%) global GFR was low. There were 7 patients (10.60%) in which pelvicalceal hold up was seen which adequately cleared with lasix. One patient ( 99m Tc-DTPA renal scintigraphy with diuretic (F+10, 30 min study) as a functional modality is significantly useful in the selection of donor kidney

  7. Achieving donor management goals before deceased donor procurement is associated with more organs transplanted per donor.

    Science.gov (United States)

    Malinoski, Darren J; Daly, Michael C; Patel, Madhukar S; Oley-Graybill, Chrystal; Foster, Clarence E; Salim, Ali

    2011-10-01

    There is a national shortage of organs available for transplantation. Implementation of preset donor management goals (DMGs) to improve outcomes is recommended, but uniform practices and data are lacking. We hypothesized that meeting DMGs before organ procurement would result in more organs transplanted per donor (OTPD). The eight organ procurement organization in United Network for Organ Sharing Region 5 selected 10 critical care end points as DMGs. Each organ procurement organization submitted retrospective data from 40 standard criteria donors. "DMGs met" was defined as achieving any eight DMGs before procurement. The primary outcome was ≥4 OTPD. Binary logistic regression was used to determine independent predictors of ≥4 OTPD with a pdonors had 3.6±1.6 OTPD. Donors with DMGs met had more OTPD (4.4 vs. 3.3, p50% (OR=4.0), Pao2:FIO2>300 (OR=4.6), and serum sodium 135 to 160 mEq/L (OR=3.4). Meeting DMGs before procurement resulted in more OTPD. Donor factors and critical care end points are independent predictors of organ yield. Prospective studies are needed to determine the true impact of each DMG on the number and function of transplanted organs.

  8. Alternative allogeneic donor sources for transplantation for childhood diseases: unrelated cord blood and haploidentical family donors.

    Science.gov (United States)

    Cairo, Mitchell S; Rocha, Vanderson; Gluckman, Eliane; Hale, Gregory; Wagner, John

    2008-01-01

    Allogeneic stem cell transplantation has been demonstrated to be curative in a wide variety of pediatric malignant and nonmalignant diseases, and can be traced back over 50 years ago to the original report of Thomas et al. HLA matched sibling donors have been the gold standard for pediatric recipients requiring allogeneic donors for both nonmalignant and malignant conditions. However, only 25% of potential pediatric recipients possesses an HLA-matched sibling donor, and the frequency is even less in those with genetic nonmalignant conditions because of genetically affected other siblings within the family. Therefore, 75% to 90% of potential pediatric recipients require alternative allogeneic donor cells for treatment of their underlying conditions. Potential alternative allogeneic donor sources include unrelated cord blood donors, unrelated adult donors, and haploidentical family donors. In this article we review the experience of both unrelated cord blood donor and haploidentical family donor transplants in selected pediatric malignant and nonmalignant conditions.

  9. Living donor liver transplantation for hepatocellular carcinoma achieves better outcomes.

    Science.gov (United States)

    Lin, Chih-Che; Chen, Chao-Long

    2016-10-01

    Liver transplantation (LT) for hepatocellular carcinoma (HCC) at Kaohsiung Chang Gung Memorial Hospital mainly relies on live donor LT (LDLT). Owing to taking the risk of LD, we are obligated to adopt strict selection criteria for HCC patients and optimize the pre-transplant conditions to ensure a high disease-free survival similar to those without HCC, even better than deceased donor LT (DDLT). Better outcomes are attributed to excellent surgical results and optimal patient selection. The hospital mortality of primary and salvage LDLT are lower than 2% in our center. Although Taiwan Health Insurance Policy extended the Milan to University of California, San Francisco (UCSF) criteria in 2006, selection criteria will not be consolidated to take into account only by the morphologic size/number of tumors but also by their biology. The criteria are divided into modifiable image morphology, alpha fetoprotein (AFP), and positron emission tomography (PET) scan with standard uptake value (SUV) and unmodifiable unfavorable pathology such as HCC combined with cholangiocarcinoma (CC), sarcomatoid type, and poor differentiation. Downstaging therapy is necessary for HCC patients beyond criteria to fit all modifiable standards. The upper limit of downstaging treatment seems to be extended by more effective drug eluting transarterial chemoembolization in cases without absolute contraindications. In contrast, the pitfall of unmodifiable tumor pathology should be excluded by the findings of pretransplant core biopsy/resection if possible. More recently, achieving complete tumor necrosis in explanted liver could almost predict no recurrence after transplant. Necrotizing therapy is advised if possible before transplant even the tumor status within criteria to minimize the possibility of tumor recurrence. LDLT with low surgical mortality in experienced centers provides the opportunities of optimizing the pre-transplant tumor conditions and timing of transplant to achieve better

  10. The ELPAT living organ donor Psychosocial Assessment Tool (EPAT): from 'what' to 'how' of psychosocial screening - a pilot study.

    Science.gov (United States)

    Massey, Emma K; Timmerman, Lotte; Ismail, Sohal Y; Duerinckx, Nathalie; Lopes, Alice; Maple, Hannah; Mega, Inês; Papachristou, Christina; Dobbels, Fabienne

    2018-01-01

    Thorough psychosocial screening of donor candidates is required in order to minimize potential negative consequences and to strive for optimal safety within living donation programmes. We aimed to develop an evidence-based tool to standardize the psychosocial screening process. Key concepts of psychosocial screening were used to structure our tool: motivation and decision-making, personal resources, psychopathology, social resources, ethical and legal factors and information and risk processing. We (i) discussed how each item per concept could be measured, (ii) reviewed and rated available validated tools, (iii) where necessary developed new items, (iv) assessed content validity and (v) pilot-tested the new items. The resulting ELPAT living organ donor Psychosocial Assessment Tool (EPAT) consists of a selection of validated questionnaires (28 items in total), a semi-structured interview (43 questions) and a Red Flag Checklist. We outline optimal procedures and conditions for implementing this tool. The EPAT and user manual are available from the authors. Use of this tool will standardize the psychosocial screening procedure ensuring that no psychosocial issues are overlooked and ensure that comparable selection criteria are used and facilitate generation of comparable psychosocial data on living donor candidates. © 2017 Steunstichting ESOT.

  11. Algorithm for recall of HIV reactive Indian blood donors by sequential immunoassays enables selective donor referral for counseling

    Directory of Open Access Journals (Sweden)

    Thakral B

    2006-01-01

    Full Text Available Background: HIV/AIDS pandemic brought into focus the importance of safe blood donor pool. Aims: To analyze true seroprevalence of HIV infection in our blood donors and devise an algorithm for donor recall avoiding unnecessary referrals to voluntary counseling and testing centre (VCTC. Materials and Methods: 39,784 blood units were screened for anti-HIV 1/2 using ELISA immunoassay (IA-1. Samples which were repeat reactive on IA-1 were further tested using two different immunoassays (IA-2 and IA-3 and Western blot (WB. Based on results of these sequential IAs and WB, an algorithm for recall of true HIV seroreactive blood donors is suggested for countries like India where nucleic acid testing or p24 antigen assays are not mandatory and given the limited resources may not be feasible. Results: The anti-HIV seroreactivity by repeat IA-1, IA-2, IA-3 and WB were 0.16%, 0.11%, 0.098% and 0.07% respectively. Of the 44 IA-1 reactive samples, 95.2% (20/21 of the seroreactive samples by both IA-2 and IA-3 were also WB positive and 100% (6/6 of the non-reactive samples by these IAs were WB negative. IA signal/cutoff ratio was significantly low in biological false reactive donors. WB indeterminate results were largely due to non-specific reactivity to gag protein (p55. Conclusions: HIV seroreactivity by sequential immunoassays (IA-1, IA-2 and IA-3; comparable to WHO Strategy-III prior to donor recall results in decreased referral to VCTC as compared to single IA (WHO Strategy-I being followed currently in India. Moreover, this strategy will repose donor confidence in our blood transfusion services and strengthen voluntary blood donation program.

  12. Development of Organ-Specific Donor Risk Indices

    Science.gov (United States)

    Akkina, Sanjeev K.; Asrani, Sumeet K.; Peng, Yi; Stock, Peter; Kim, Ray; Israni, Ajay K.

    2012-01-01

    Due to the shortage of deceased donor organs, transplant centers accept organs from marginal deceased donors, including older donors. Organ-specific donor risk indices have been developed to predict graft survival using various combinations of donor and recipient characteristics. We will review the kidney donor risk index (KDRI) and liver donor risk index (LDRI) and compare and contrast their strengths, limitations, and potential uses. The Kidney Donor Risk Index has a potential role in developing new kidney allocation algorithms. The Liver Donor Risk Index allows for greater appreciation of the importance of donor factors, particularly for hepatitis C-positive recipients; as the donor risk index increases, rates of allograft and patient survival among these recipients decrease disproportionately. Use of livers with high donor risk index is associated with increased hospital costs independent of recipient risk factors, and transplanting livers with high donor risk index into patients with Model for End-Stage Liver Disease scores Donor Risk Index has limited this practice. Significant regional variation in donor quality, as measured by the Liver Donor Risk Index, remains in the United States. We also review other potential indices for liver transplant, including donor-recipient matching and the retransplant donor risk index. While substantial progress has been made in developing donor risk indices to objectively assess donor variables that affect transplant outcomes, continued efforts are warranted to improve these indices to enhance organ allocation policies and optimize allograft survival. PMID:22287036

  13. Incidence and distribution of transplantable organs from donors after circulatory determination of death in U.S. intensive care units.

    Science.gov (United States)

    Halpern, Scott D; Hasz, Richard D; Abt, Peter L

    2013-04-01

    All U.S. acute care hospitals must maintain protocols for recovering organs from donors after circulatory determination of death (DCDD), but the numbers, types, and whereabouts of available organs are unknown. To assess the maximal potential supply and distribution of DCDD organs in U.S. intensive care units. We conducted a population-based cohort study among a randomly selected sample of 50 acute care hospitals in the highest-volume donor service area in the United States. We identified all potentially eligible donors dying within 90 minutes of the withdrawal of life-sustaining therapy from July 1, 2008 to June 30, 2009. Using prespecified criteria, potential donors were categorized as optimal, suboptimal, or ineligible to donate their lungs, kidneys, pancreas, or liver. If only optimal DCDD organs were used, the deceased donor supplies of these organs could increase by up to 22.7, 8.9, 7.4, and 3.3%, respectively. If optimal and suboptimal DCDD organs were used, the corresponding supply increases could be up to 50.0, 19.7, 18.5, and 10.9%. Three-quarters of DCDD organs could be recovered from the 17.2% of hospitals with the highest annual donor volumes-typically those with trauma centers and more than 20 intensive care unit beds. Universal identification and referral of DCDD could increase the supply of transplantable lungs by up to one-half, and would not increase any other organ supply by more than one-fifth. The marked clustering of DCDD among a small number of identifiable hospitals could guide targeted interventions to improve DCDD identification, referral, and management.

  14. Development of organ-specific donor risk indices.

    Science.gov (United States)

    Akkina, Sanjeev K; Asrani, Sumeet K; Peng, Yi; Stock, Peter; Kim, W Ray; Israni, Ajay K

    2012-04-01

    Because of the shortage of deceased donor organs, transplant centers accept organs from marginal deceased donors, including older donors. Organ-specific donor risk indices have been developed to predict graft survival with various combinations of donor and recipient characteristics. Here we review the kidney donor risk index (KDRI) and the liver donor risk index (LDRI) and compare and contrast their strengths, limitations, and potential uses. The KDRI has a potential role in developing new kidney allocation algorithms. The LDRI allows a greater appreciation of the importance of donor factors, particularly for hepatitis C virus-positive recipients; as the donor risk index increases, the rates of allograft and patient survival among these recipients decrease disproportionately. The use of livers with high donor risk indices is associated with increased hospital costs that are independent of recipient risk factors, and the transplantation of livers with high donor risk indices into patients with Model for End-Stage Liver Disease scores indices for liver transplantation, including donor-recipient matching and the retransplant donor risk index. Although substantial progress has been made in developing donor risk indices to objectively assess donor variables that affect transplant outcomes, continued efforts are warranted to improve these indices to enhance organ allocation policies and optimize allograft survival. Copyright © 2012 American Association for the Study of Liver Diseases.

  15. Heart transplantation from older donors

    Directory of Open Access Journals (Sweden)

    V. N. Poptsov

    2017-01-01

    Full Text Available In the current situation of the shortage of suitable donor organs, heart transplantation from older donors is one of the ways to increase the performance of more heart transplants, particularly, in patients with urgent need of transplantation. While planning a heart transplantation from older donor one should consider increased risk of early cardiac allograft dysfunction, preexisting coronary artery disease, accelerated transplant vasculopathy which may adversely affect early and long-term survival of recipients. Subject to careful selection of donor–recipient pairs, effective prevention and treatment of early cardiac allograft dysfunction, pre-existing atherosclerosis and transplant vasculopathy the early and long-term survival of heart transplant recipients from older donors is comparable to heart transplantation from young donors.

  16. Ex-vivo partial nephrectomy after living donor nephrectomy: Surgical technique for expanding kidney donor pool

    Directory of Open Access Journals (Sweden)

    Yaw A Nyame

    2017-01-01

    Full Text Available Renal transplantation has profound improvements in mortality, morbidity, and overall quality of life compared to renal replacement therapy. This report aims to illustrate the use of ex-vivo partial nephrectomy in a patient with a renal angiomyolipoma prior to living donor transplantation. The surgical outcomes of the donor nephrectomy and recipient transplantation are reported with 2 years of follow-up. Both the donor and recipient are healthy and without any significant comorbidities. In conclusion, urologic techniques such as partial nephrectomy can be used to expand the living donor pool in carefully selected and well informed transplant recipients. Our experience demonstrated a safe and positive outcome for both the recipient and donor, and is consistent with other reported outcomes in the literature.

  17. Being a haematopoietic stem cell donor for a sick sibling: Adult donors' experiences prior to donation.

    Science.gov (United States)

    Kisch, Annika; Bolmsjö, Ingrid; Lenhoff, Stig; Bengtsson, Mariette

    2015-10-01

    There is a lack of knowledge about sibling stem cell donors' experiences pre-donation and the waiting period before the donation might have been long. The donors and their corresponding sibling recipients were simultaneously included in two different interview studies. The results from the recipient study have been presented in a separate paper. The aim was to explore the experiences of being a stem cell donor for a sibling, prior to donation. Ten adult sibling donors were interviewed prior to stem cell donation. The interviews were digitally recorded, transcribed verbatim and subjected to qualitative content analysis. The main theme Being a cog in a big wheel describes the complex process of being a sibling donor prior to donation, covering a mixture of emotions and thoughts. The four subthemes Being available, Being anxious, Being concerned and Being obliged cover the various experiences. The sibling donors' experiences are influenced by the quality of the relationship with the sick sibling. Sibling stem cell donors go through a complex process once they have accidentally got involved in. They have been asked to become a donor; it was not a voluntary choice. In caring for sibling stem cell donors the nurses should be aware of the complexity of the process they experience and take into consideration their personal situation and needs. Providing optimal care for both sibling donors and their corresponding recipients is a challenge, and further improvement and exploration are needed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Optimal selection of TLD chips

    International Nuclear Information System (INIS)

    Phung, P.; Nicoll, J.J.; Edmonds, P.; Paris, M.; Thompson, C.

    1996-01-01

    Large sets of TLD chips are often used to measure beam dose characteristics in radiotherapy. A sorting method is presented to allow optimal selection of chips from a chosen set. This method considers the variation

  19. Phage display selection of efficient glutamine-donor substrate peptides for transglutaminase 2.

    Science.gov (United States)

    Keresztessy, Zsolt; Csosz, Eva; Hársfalvi, Jolán; Csomós, Krisztián; Gray, Joe; Lightowlers, Robert N; Lakey, Jeremy H; Balajthy, Zoltán; Fésüs, László

    2006-11-01

    Understanding substrate specificity and identification of natural targets of transglutaminase 2 (TG2), the ubiquitous multifunctional cross-linking enzyme, which forms isopeptide bonds between protein-linked glutamine and lysine residues, is crucial in the elucidation of its physiological role. As a novel means of specificity analysis, we adapted the phage display technique to select glutamine-donor substrates from a random heptapeptide library via binding to recombinant TG2 and elution with a synthetic amine-donor substrate. Twenty-six Gln-containing sequences from the second and third biopanning rounds were susceptible for TG2-mediated incorporation of 5-(biotinamido)penthylamine, and the peptides GQQQTPY, GLQQASV, and WQTPMNS were modified most efficiently. A consensus around glutamines was established as pQX(P,T,S)l, which is consistent with identified substrates listed in the TRANSDAB database. Database searches showed that several proteins contain peptides similar to the phage-selected sequences, and the N-terminal glutamine-rich domain of SWI1/SNF1-related chromatin remodeling proteins was chosen for detailed analysis. MALDI/TOF and tandem mass spectrometry-based studies of a representative part of the domain, SGYGQQGQTPYYNQQSPHPQQQQPPYS (SnQ1), revealed that Q(6), Q(8), and Q(22) are modified by TG2. Kinetic parameters of SnQ1 transamidation (K(M)(app) = 250 microM, k(cat) = 18.3 sec(-1), and k(cat)/K(M)(app) = 73,200) classify it as an efficient TG2 substrate. Circular dichroism spectra indicated that SnQ1 has a random coil conformation, supporting its accessibility in the full-length parental protein. Added together, here we report a novel use of the phage display technology with great potential in transglutaminase research.

  20. The effect of whole-blood donor adverse events on blood donor return rates.

    Science.gov (United States)

    Newman, Bruce H; Newman, Daniel T; Ahmad, Raffat; Roth, Arthur J

    2006-08-01

    Some blood donation-related adverse events (AEs) can negatively impact the blood donor return rate (BDRR) and decrease donor retention. One-thousand randomly selected whole-blood donors were interviewed 3 weeks after a 525-mL index whole-blood donation for seven AEs. The number of return visits and duration of follow-up were recorded for each of the 1000 donors. A negative binomial regression analysis was used to determine the contribution of the four most common AEs to the BDRR, and interactions between these AEs were also evaluated. The four most common AEs were bruise alone (15.1%), sore arm "alone" (7.0%), fatigue "alone" (5.1%), and donor reaction "alone" (4.2%), where "alone" is defined to also include donors who had a bruise but no other AE. The estimated BDRR for donations without AEs was 1.32 visits per year. The estimated BDRRs for the four most common AEs were: bruise alone, 1.32 visits per year; sore arm alone, 1.30 visits per year (2% reduction in BDRR); fatigue alone, 1.06 visits per year (20% reduction in BDRR); and donor reaction alone, 0.87 visits per year (34% reduction in BDRR). The BDRR for donor reaction, fatigue, and sore arm together was 0.20 visits per year (85% reduction in BDRR). Donor reaction had the most negative impact on the BDRR. There appears to be a synergistic effect between donor reaction, fatigue, and sore arm. Theoretically, amelioration of some AEs has the potential to improve BDRRs.

  1. Combinatorial Optimization in Project Selection Using Genetic Algorithm

    Science.gov (United States)

    Dewi, Sari; Sawaluddin

    2018-01-01

    This paper discusses the problem of project selection in the presence of two objective functions that maximize profit and minimize cost and the existence of some limitations is limited resources availability and time available so that there is need allocation of resources in each project. These resources are human resources, machine resources, raw material resources. This is treated as a consideration to not exceed the budget that has been determined. So that can be formulated mathematics for objective function (multi-objective) with boundaries that fulfilled. To assist the project selection process, a multi-objective combinatorial optimization approach is used to obtain an optimal solution for the selection of the right project. It then described a multi-objective method of genetic algorithm as one method of multi-objective combinatorial optimization approach to simplify the project selection process in a large scope.

  2. Donor insemination: eugenic and feminist implications.

    Science.gov (United States)

    Hanson, F A

    2001-09-01

    One concern regarding developments in genetics is that, when techniques such as genetic engineering become safe and affordable, people will use them for positive eugenics: to "improve" their offspring by enpowering them with exceptional qualities. Another is whether new reproductive technologies are being used to improve the condition of women or as the tools of a patriarchal system that appropriates female functions to itself and exploits women to further its own ends. Donor insemination is relevant to both of these issues. The degree to which people have used donor insemination in the past for positive eugenic purposes may give some insight into the likelihood of developing technologies being so used in the future. Donor insemination provides women with the opportunity to reproduce with only the most remote involvement of a man. To what degree do women take advantage of this to liberate themselves from male dominance? Through questionnaires and interviews, women who have used donor insemination disclosed their criteria for selecting sperm donors. The results are analyzed for the prevalence of positive eugenic criteria in the selection process and women's attitudes toward minimizing the male role in reproduction.

  3. Optimal Bandwidth Selection for Kernel Density Functionals Estimation

    Directory of Open Access Journals (Sweden)

    Su Chen

    2015-01-01

    Full Text Available The choice of bandwidth is crucial to the kernel density estimation (KDE and kernel based regression. Various bandwidth selection methods for KDE and local least square regression have been developed in the past decade. It has been known that scale and location parameters are proportional to density functionals ∫γ(xf2(xdx with appropriate choice of γ(x and furthermore equality of scale and location tests can be transformed to comparisons of the density functionals among populations. ∫γ(xf2(xdx can be estimated nonparametrically via kernel density functionals estimation (KDFE. However, the optimal bandwidth selection for KDFE of ∫γ(xf2(xdx has not been examined. We propose a method to select the optimal bandwidth for the KDFE. The idea underlying this method is to search for the optimal bandwidth by minimizing the mean square error (MSE of the KDFE. Two main practical bandwidth selection techniques for the KDFE of ∫γ(xf2(xdx are provided: Normal scale bandwidth selection (namely, “Rule of Thumb” and direct plug-in bandwidth selection. Simulation studies display that our proposed bandwidth selection methods are superior to existing density estimation bandwidth selection methods in estimating density functionals.

  4. Inflammatory markers as selection criteria of hepatocellular carcinoma in living-donor liver transplantation.

    Science.gov (United States)

    Na, Gun Hyung; Kim, Dong Goo; Han, Jae Hyun; Kim, Eun Young; Lee, Soo Ho; Hong, Tae Ho; You, Young Kyoung

    2014-06-07

    To investigate that inflammatory markers can predict accurately the prognosis of hepatocelluar carcinoma (HCC) patients in living-donor liver transplantation (LDLT). From October 2000 to November 2011, 224 patients who underwent living donor liver transplantation for HCC at our institution were enrolled in this study. We analyzed disease-free survival (DFS) and overall survival (OS) after LT in patients with HCC and designed a new score model using pretransplant neutrophil-lymphocyte ratio (NLR) and C-reactive protein (CRP). The DFS and OS in patients with an NLR level ≥ 6.0 or CRP level ≥ 1.0 were significantly worse than those of patients with an NLR level < 6.0 or CRP level < 1.0 (P = 0.049, P = 0.003 for NLR and P = 0.010, P < 0.001 for CRP, respectively). Using a new score model using the pretransplant NLR and CRP, we can differentiate HCC patients beyond the Milan criteria with a good prognosis from those with a poor prognosis. Combined with the Milan criteria, new score model using NLR and CRP represent new selection criteria for LDLT candidates with HCC, especially beyond the Milan criteria.

  5. The healthy donor effect impacts self-reported physical and mental health - results from the Danish Blood Donor Study (DBDS)

    DEFF Research Database (Denmark)

    Rigas, A S; Skytthe, A; Erikstrup, C

    2017-01-01

    AIMS: This study aimed at quantifying the healthy donor effect by comparing self-perceived mental and physical health between blood donors and non-donors. BACKGROUND: In theory, the selection process known as the healthy donor effect should result in better self-perceived, health-related quality...... of life in donors than in non-donors. METHODS: The Short Form-12 data from the Danish Twin Registry (DTR) was compared with the data from the Danish Blood Donor Study (DBDS). Data on age, sex and smoking status were included in the analyses. The multivariable linear regression analysis was stratified......-perceived mental health was associated with a blood donor. With the increase in age, better self-perceived physical health was associated with blood donation....

  6. Pareto-Optimal Model Selection via SPRINT-Race.

    Science.gov (United States)

    Zhang, Tiantian; Georgiopoulos, Michael; Anagnostopoulos, Georgios C

    2018-02-01

    In machine learning, the notion of multi-objective model selection (MOMS) refers to the problem of identifying the set of Pareto-optimal models that optimize by compromising more than one predefined objectives simultaneously. This paper introduces SPRINT-Race, the first multi-objective racing algorithm in a fixed-confidence setting, which is based on the sequential probability ratio with indifference zone test. SPRINT-Race addresses the problem of MOMS with multiple stochastic optimization objectives in the proper Pareto-optimality sense. In SPRINT-Race, a pairwise dominance or non-dominance relationship is statistically inferred via a non-parametric, ternary-decision, dual-sequential probability ratio test. The overall probability of falsely eliminating any Pareto-optimal models or mistakenly returning any clearly dominated models is strictly controlled by a sequential Holm's step-down family-wise error rate control method. As a fixed-confidence model selection algorithm, the objective of SPRINT-Race is to minimize the computational effort required to achieve a prescribed confidence level about the quality of the returned models. The performance of SPRINT-Race is first examined via an artificially constructed MOMS problem with known ground truth. Subsequently, SPRINT-Race is applied on two real-world applications: 1) hybrid recommender system design and 2) multi-criteria stock selection. The experimental results verify that SPRINT-Race is an effective and efficient tool for such MOMS problems. code of SPRINT-Race is available at https://github.com/watera427/SPRINT-Race.

  7. Managing the Public Sector Research and Development Portfolio Selection Process: A Case Study of Quantitative Selection and Optimization

    Science.gov (United States)

    2016-09-01

    PUBLIC SECTOR RESEARCH & DEVELOPMENT PORTFOLIO SELECTION PROCESS: A CASE STUDY OF QUANTITATIVE SELECTION AND OPTIMIZATION by Jason A. Schwartz...PUBLIC SECTOR RESEARCH & DEVELOPMENT PORTFOLIO SELECTION PROCESS: A CASE STUDY OF QUANTITATIVE SELECTION AND OPTIMIZATION 5. FUNDING NUMBERS 6...describing how public sector organizations can implement a research and development (R&D) portfolio optimization strategy to maximize the cost

  8. Optimal control of bond selectivity in unimolecular reactions

    International Nuclear Information System (INIS)

    Shi Shenghua; Rabitz, H.

    1991-01-01

    The optimal control theory approach to designing optimal fields for bond-selective unimolecular reactions is presented. A set of equations for determining the optimal fields, which will lead to the achievement of the objective of bond-selective dissociation is developed. The numerical procedure given for solving these equations requires the repeated calculation of the time propagator for the system with the time-dependent Hamiltonian. The splitting approximation combined with the fast Fourier transform algorithm is used for computing the short time propagator. As an illustrative example, a model linear triatomic molecule is treated. The model system consists of two Morse oscillators coupled via kinetic coupling. The magnitude of the dipoles of the two Morse oscillators are the same, the fundamental frequencies are almost the same, but the dissociation energies are different. The rather demanding objective under these conditions is to break the stronger bond while leaving the weaker one intact. It is encouraging that the present computational method efficiently gives rise to the optimal field, which leads to the excellent achievement of the objective of bond selective dissociation. (orig.)

  9. [Cloning goat producing human lactoferrin with genetically modified donor cells selected by single or dual markers].

    Science.gov (United States)

    An, Liyou; Yuan, Yuguo; Yu, Baoli; Yang, Tingjia; Cheng, Yong

    2012-12-01

    We compared the efficiency of cloning goat using human lactoferrin (hLF) with genetically modified donor cells marked by single (Neo(r)) or double (Neo(r)/GFP) markers. Single marker expression vector (pBLC14) or dual markers expression vector (pAPLM) was delivered to goat fetal fibroblasts (GFF), and then the transgenic GFF was used as donor cells to produce transgenic goats. Respectively, 58.8% (20/34) and 86.7% (26/30) resistant cell lines confirmed the transgenic integration by PCR. Moreover, pAPLM cells lines were subcultured with several passages, only 20% (6/30) cell lines was observed fluorescence from each cell during the cell passage. Somatic cell nuclear transfer using the donor cells harbouring pBLC14 or pAPLM construct, resulting in a total of 806 reconstructed embryos, a pregnancy rate at 35 d (53.8%, 39.1%) and 60 d (26.9%, 21.7%), and an offspring birth rate (1.9%, 1.4%) with 5 and 7 newborn cloned goats, respectively. Transgene was confirmed by PCR and southern-blot in all cloned offspring. There were no significant differences at the reconstructed embryo fusion rates, pregnancy rates and the birth rate (P > 0.05) between single and double markers groups. The Neo(r)/GFP double markers could improve the reliability for accurately and efficiently selecting the genetically modified donor cells. No adverse effect was observed on the efficiency of transgenic goat production by SCNT using somatic cells transfected with double (Neo(r)/GFP) markers vector.

  10. The evaluation of blood donor deferral causes in Zimbabwe

    NARCIS (Netherlands)

    Mafirakureva, N.; Khoza, S.; Van Hulst, M.; Postma, M.J.; Mvere, D.A.

    2013-01-01

    Background: Donor selection is one of the first steps in blood donation aimed at improving the safety of blood and blood products. It is the only line of protection for donors and against certain infections for which testing is not performed. There is paucity of published data on reasons for donor

  11. Three novel triazine-based materials with different O/S/N set of donor atoms: One-step preparation and comparison of their capability in selective separation of uranium

    International Nuclear Information System (INIS)

    Bai, Chiyao; Zhang, Meicheng; Li, Bo; Tian, Yin; Zhang, Shuang; Zhao, Xiaosheng; Li, Yang; Wang, Lei; Ma, Lijian; Li, Shoujian

    2015-01-01

    Highlights: • Three novel functional covalent triazine-based frameworks are prepared. • Synthesis and functionalization of the products are accomplished in one step. • Various adsorbents can be prepared using cyanuric chloride as a core skeleton. • The products have high N concentration, regular structures, and high stabilities. • The products exhibit high sorption capacities and distinct selectivity for U (VI). - Abstract: Cyanuric chloride was chosen as a core skeleton which reacted with desired linker molecules, urea, thiourea and thiosemicarbazide, to prepare three novel functional covalent triazine-based frameworks, CCU (O-donor set), CCTU (S-donor set) and CCTS (S, N-donor set) respectively, designed for selective adsorption of U(VI). The products have high nitrogen concentration (>30 wt%), regular structure, relatively high chemical and thermal stability. Adsorption behaviors of the products on U(VI) were examined by batch experiments. CCU and CCTU can extract U(VI) from simulated nuclear industrial effluent containing 12 co-existing cations with relatively high selectivity (54.4% and 54.2%, respectively). Especially, effects of donor atoms O/S on adsorption were investigated, and the outcomes indicate that the difference in coordinating ability between the donor atoms is weakened in large conjugated systems, and the related functional groups with originally very strong coordination abilities may not be the best choice for the application in selective adsorption of uranium and also other metals. The as-proposed approach can easily be expanded into design and preparation of new highly efficient adsorbents for selective separation and recovery of uranium through adjusting the structures, types and amounts of functional groups of adsorbents by choosing suitable linkers.

  12. Feature selection for portfolio optimization

    DEFF Research Database (Denmark)

    Bjerring, Thomas Trier; Ross, Omri; Weissensteiner, Alex

    2016-01-01

    Most portfolio selection rules based on the sample mean and covariance matrix perform poorly out-of-sample. Moreover, there is a growing body of evidence that such optimization rules are not able to beat simple rules of thumb, such as 1/N. Parameter uncertainty has been identified as one major....... While most of the diversification benefits are preserved, the parameter estimation problem is alleviated. We conduct out-of-sample back-tests to show that in most cases different well-established portfolio selection rules applied on the reduced asset universe are able to improve alpha relative...

  13. The Psychosocial and Independent Living Donor Advocate Evaluation and Post-surgery Care of Living Donors.

    Science.gov (United States)

    Rudow, Dianne LaPointe; Swartz, Kathleen; Phillips, Chelsea; Hollenberger, Jennifer; Smith, Taylor; Steel, Jennifer L

    2015-09-01

    Solid organ transplantation as a treatment for end stage organ failure has been an accepted treatment option for decades. Despite advances in medicine and technology, and increased awareness of organ donation and transplantation, the gap between supply and demand continues to widen. Living donation has been an option that has increased the number of transplants despite the continued shortage of deceased organs. In the early 2000s live donor transplantation reached an all-time high in the United States. As a result, a consensus meeting was convened in 2000 to increase the oversight of living donor transplantation. Both the Centers for Medicare and Medicaid Services and the United Network for Organ Sharing developed regulations that transplant programs performing live donor transplantation. These regulations and guidelines involve the education, evaluation, informed consent process and living donor follow-up care. Two areas in which had significant changes included the psychosocial and the independent living donor advocate (ILDA) evaluation. The purpose of this paper was to outline the current regulations and guidelines associated with the psychosocial and ILDA evaluation as well as provide further recommendations for the administration of a high quality evaluation of living donors. The goals and timing of the evaluation and education of donors; qualifications of the health care providers performing the evaluation; components of the evaluation; education provided to donors; documentation of the evaluation; participation in the selection committee meeting; post-decline and post-donation care of donors is described. Caveats including the paired donor exchange programs and non-directed and directed donation are also considered.

  14. Recruitment of feces donors among blood donors

    DEFF Research Database (Denmark)

    Dahl Jørgensen, Simon Mark; Erikstrup, Christian; Dinh, Khoa Manh

    2018-01-01

    As the use of fecal microbiota transplantation (FMT) has gained momentum, an increasing need for continuous access to healthy feces donors has developed. Blood donors constitute a healthy subset of the general population and may serve as an appropriate group for recruitment. In this study, we...... investigated the suitability of blood donors as feces donors. In a prospective cohort study, we recruited blood donors onsite at a public Danish blood bank. Following their consent, the blood donors underwent a stepwise screening process: First, blood donors completed an electronic pre-screening questionnaire...... to rule out predisposing risk factors. Second, eligible blood donors had blood and fecal samples examined. Of 155 blood donors asked to participate, 137 (88%) completed the electronic pre-screening questionnaire, 16 declined, and 2 were excluded. Of the 137 donors who completed the questionnaire, 79 (58...

  15. Neonatal bone marrow transplantation of ADA-deficient SCID mice results in immunologic reconstitution despite low levels of engraftment and an absence of selective donor T lymphoid expansion.

    Science.gov (United States)

    Carbonaro, Denise A; Jin, Xiangyang; Cotoi, Daniel; Mi, Tiejuan; Yu, Xiao-Jin; Skelton, Dianne C; Dorey, Frederick; Kellems, Rodney E; Blackburn, Michael R; Kohn, Donald B

    2008-06-15

    Adenosine deaminase (ADA)-deficient severe combined immune deficiency (SCID) may be treated by allogeneic hematopoietic stem cell transplantation without prior cytoreductive conditioning, although the mechanism of immune reconstitution is unclear. We studied this process in a murine gene knockout model of ADA-deficient SCID. Newborn ADA-deficient pups received transplants of intravenous infusion of normal congenic bone marrow, without prior cytoreductive conditioning, which resulted in long-term survival, multisystem correction, and nearly normal lymphocyte numbers and mitogenic proliferative responses. Only 1% to 3% of lymphocytes and myeloid cells were of donor origin without a selective expansion of donor-derived lymphocytes; immune reconstitution was by endogenous, host-derived ADA-deficient lymphocytes. Preconditioning of neonates with 100 to 400 cGy of total body irradiation before normal donor marrow transplant increased the levels of engrafted donor cells in a radiation dose-dependent manner, but the chimerism levels were similar for lymphoid and myeloid cells. The absence of selective reconstitution by donor T lymphocytes in the ADA-deficient mice indicates that restoration of immune function occurred by rescue of endogenous ADA-deficient lymphocytes through cross-correction from the engrafted ADA-replete donor cells. Thus, ADA-deficient SCID is unique in its responses to nonmyeloablative bone marrow transplantation, which has implications for clinical bone marrow transplantation or gene therapy.

  16. Deceased-Donor Smoking History Is Associated With Increased Recipient Mortality After Kidney Transplant: A Population-Cohort Study.

    Science.gov (United States)

    Gillott, Holly; Jackson Spence, Francesca; Tahir, Sanna; Hodson, James; Nath, Jay; Sharif, Adnan

    2018-05-16

    Historical data have suggested that donor smoking is associated with detrimental clinical outcomes for recipients of kidneys from deceased donors. However, the effects of smoking status of a kidney donor on the outcomes of the recipient in a contemporary setting of immunosuppression and transplant practice have not yet been ascertained. This retrospective, population-cohort study analyzed data of all deceased-donor kidney-alone transplant procedures performed in the United Kingdom between April 2001 and April 2013. Our study included 11?199 deceased-donor kidney allograft recipients, with median follow-up of 46 months posttransplant. In our cohort, 5280 deceased donors (47.1%) had a documented history of smoking. Deceased donors with versus those without smoking history were more likely to be younger (mean age of 48 vs 50 years; P history (hazard ratio of 1.12, 95% confidence interval, 1.00-1.25; P = .044). No significant association was seen for death-censored or overall graft survival. Our multivariate survival analyses showed that, after accounting for confounding factors, the effects of donor smoking status remained significant for patient survival (hazard ratio of 1.16, 95% CI, 1.03-1.29; P =.011) but not graft survival. This population-cohort study suggests that deceased-donor kidneys from smokers contribute to an increased risk of death for kidney allograft recipients. These study findings imply donor smoking history should be factored into the risk stratification decision for recipient selection to optimize decision making; however, further clarification and validation of these data are warranted.

  17. SU-F-R-10: Selecting the Optimal Solution for Multi-Objective Radiomics Model

    International Nuclear Information System (INIS)

    Zhou, Z; Folkert, M; Wang, J

    2016-01-01

    Purpose: To develop an evidential reasoning approach for selecting the optimal solution from a Pareto solution set obtained by a multi-objective radiomics model for predicting distant failure in lung SBRT. Methods: In the multi-objective radiomics model, both sensitivity and specificity are considered as the objective functions simultaneously. A Pareto solution set with many feasible solutions will be resulted from the multi-objective optimization. In this work, an optimal solution Selection methodology for Multi-Objective radiomics Learning model using the Evidential Reasoning approach (SMOLER) was proposed to select the optimal solution from the Pareto solution set. The proposed SMOLER method used the evidential reasoning approach to calculate the utility of each solution based on pre-set optimal solution selection rules. The solution with the highest utility was chosen as the optimal solution. In SMOLER, an optimal learning model coupled with clonal selection algorithm was used to optimize model parameters. In this study, PET, CT image features and clinical parameters were utilized for predicting distant failure in lung SBRT. Results: Total 126 solution sets were generated by adjusting predictive model parameters. Each Pareto set contains 100 feasible solutions. The solution selected by SMOLER within each Pareto set was compared to the manually selected optimal solution. Five-cross-validation was used to evaluate the optimal solution selection accuracy of SMOLER. The selection accuracies for five folds were 80.00%, 69.23%, 84.00%, 84.00%, 80.00%, respectively. Conclusion: An optimal solution selection methodology for multi-objective radiomics learning model using the evidential reasoning approach (SMOLER) was proposed. Experimental results show that the optimal solution can be found in approximately 80% cases.

  18. SU-F-R-10: Selecting the Optimal Solution for Multi-Objective Radiomics Model

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Z; Folkert, M; Wang, J [UT Southwestern Medical Center, Dallas, TX (United States)

    2016-06-15

    Purpose: To develop an evidential reasoning approach for selecting the optimal solution from a Pareto solution set obtained by a multi-objective radiomics model for predicting distant failure in lung SBRT. Methods: In the multi-objective radiomics model, both sensitivity and specificity are considered as the objective functions simultaneously. A Pareto solution set with many feasible solutions will be resulted from the multi-objective optimization. In this work, an optimal solution Selection methodology for Multi-Objective radiomics Learning model using the Evidential Reasoning approach (SMOLER) was proposed to select the optimal solution from the Pareto solution set. The proposed SMOLER method used the evidential reasoning approach to calculate the utility of each solution based on pre-set optimal solution selection rules. The solution with the highest utility was chosen as the optimal solution. In SMOLER, an optimal learning model coupled with clonal selection algorithm was used to optimize model parameters. In this study, PET, CT image features and clinical parameters were utilized for predicting distant failure in lung SBRT. Results: Total 126 solution sets were generated by adjusting predictive model parameters. Each Pareto set contains 100 feasible solutions. The solution selected by SMOLER within each Pareto set was compared to the manually selected optimal solution. Five-cross-validation was used to evaluate the optimal solution selection accuracy of SMOLER. The selection accuracies for five folds were 80.00%, 69.23%, 84.00%, 84.00%, 80.00%, respectively. Conclusion: An optimal solution selection methodology for multi-objective radiomics learning model using the evidential reasoning approach (SMOLER) was proposed. Experimental results show that the optimal solution can be found in approximately 80% cases.

  19. An intutionistic fuzzy optimization approach to vendor selection problem

    Directory of Open Access Journals (Sweden)

    Prabjot Kaur

    2016-09-01

    Full Text Available Selecting the right vendor is an important business decision made by any organization. The decision involves multiple criteria and if the objectives vary in preference and scope, then nature of decision becomes multiobjective. In this paper, a vendor selection problem has been formulated as an intutionistic fuzzy multiobjective optimization where appropriate number of vendors is to be selected and order allocated to them. The multiobjective problem includes three objectives: minimizing the net price, maximizing the quality, and maximizing the on time deliveries subject to supplier's constraints. The objection function and the demand are treated as intutionistic fuzzy sets. An intutionistic fuzzy set has its ability to handle uncertainty with additional degrees of freedom. The Intutionistic fuzzy optimization (IFO problem is converted into a crisp linear form and solved using optimization software Tora. The advantage of IFO is that they give better results than fuzzy/crisp optimization. The proposed approach is explained by a numerical example.

  20. Pure 3D laparoscopic living donor right hemihepatectomy in a donor with separate right posterior and right anterior hepatic ducts and portal veins.

    Science.gov (United States)

    Hong, Suk Kyun; Suh, Kyung-Suk; Kim, Hyo-Sin; Yoon, Kyung Chul; Ahn, Sung-Woo; Oh, Dongkyu; Kim, Hyeyoung; Yi, Nam-Joon; Lee, Kwang-Woong

    2017-11-01

    Despite increases in the performance of pure laparoscopic living donor hepatectomy, variations in the bile duct or portal vein have been regarded as relative contraindications to this technique [1-3]. This report describes a donor with separate right posterior and right anterior hepatic ducts and portal veins who underwent pure laparoscopic living donor right hemihepatectomy, integrated with 3D laparoscopy and indocyanine green (ICG) near-infrared fluorescence cholangiography [1, 4, 5]. A 50-year-old man offered to donate part of his liver to his older brother, who required a transplant for hepatitis B-associated liver cirrhosis and hepatocellular carcinoma. Donor height was 178.0 cm, body weight was 82.7 kg, and body mass index was 26.1 kg/m 2 . Preoperative computed tomography and magnetic resonance cholangiopancreatography showed that the donor had separate right posterior and right anterior hepatic ducts and portal veins. The entire procedure was performed under 3D laparoscopic view. Following intravenous injections of 0.05 mg/kg ICG, ICG near-infrared fluorescence camera was used to demarcate the exact transection line and determine the optimal bile duct division point. The total operation time was 443 min; the donor required no transfusions and experienced no intraoperative complications. The graft weighed 1146 g with a graft-to-recipient weight ratio of 1.88%. The optimal bile duct division point was identified using ICG fluorescence cholangiography, and the bile duct was divided with good patency without any stricture. The right anterior and posterior portal veins were transected with endostaplers without any torsion. The patient was discharged on postoperative day 8, with no complications. Using a 3D view and ICG fluorescence cholangiography, pure 3D laparoscopic living donor right hemihepatectomy is feasible in a donor with separate right posterior and right anterior hepatic ducts and portal veins.

  1. Optimization methods for activities selection problems

    Science.gov (United States)

    Mahad, Nor Faradilah; Alias, Suriana; Yaakop, Siti Zulaika; Arshad, Norul Amanina Mohd; Mazni, Elis Sofia

    2017-08-01

    Co-curriculum activities must be joined by every student in Malaysia and these activities bring a lot of benefits to the students. By joining these activities, the students can learn about the time management and they can developing many useful skills. This project focuses on the selection of co-curriculum activities in secondary school using the optimization methods which are the Analytic Hierarchy Process (AHP) and Zero-One Goal Programming (ZOGP). A secondary school in Negeri Sembilan, Malaysia was chosen as a case study. A set of questionnaires were distributed randomly to calculate the weighted for each activity based on the 3 chosen criteria which are soft skills, interesting activities and performances. The weighted was calculated by using AHP and the results showed that the most important criteria is soft skills. Then, the ZOGP model will be analyzed by using LINGO Software version 15.0. There are two priorities to be considered. The first priority which is to minimize the budget for the activities is achieved since the total budget can be reduced by RM233.00. Therefore, the total budget to implement the selected activities is RM11,195.00. The second priority which is to select the co-curriculum activities is also achieved. The results showed that 9 out of 15 activities were selected. Thus, it can concluded that AHP and ZOGP approach can be used as the optimization methods for activities selection problem.

  2. On Optimal Input Design and Model Selection for Communication Channels

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yanyan [ORNL; Djouadi, Seddik M [ORNL; Olama, Mohammed M [ORNL

    2013-01-01

    In this paper, the optimal model (structure) selection and input design which minimize the worst case identification error for communication systems are provided. The problem is formulated using metric complexity theory in a Hilbert space setting. It is pointed out that model selection and input design can be handled independently. Kolmogorov n-width is used to characterize the representation error introduced by model selection, while Gel fand and Time n-widths are used to represent the inherent error introduced by input design. After the model is selected, an optimal input which minimizes the worst case identification error is shown to exist. In particular, it is proven that the optimal model for reducing the representation error is a Finite Impulse Response (FIR) model, and the optimal input is an impulse at the start of the observation interval. FIR models are widely popular in communication systems, such as, in Orthogonal Frequency Division Multiplexing (OFDM) systems.

  3. Selected Mildly Obese Donors Can Be Used Safely in Simultaneous Pancreas and Kidney Transplantation.

    Science.gov (United States)

    Alhamad, Tarek; Malone, Andrew F; Lentine, Krista L; Brennan, Daniel C; Wellen, Jason; Chang, Su-Hsin; Chakkera, Harini A

    2017-06-01

    Donor obesity, defined as donor body mass index (D-BMI) of 30 kg/m or greater, has been associated with increased risk of technical failure and poor pancreas allograft outcomes. Many transplant centers establish a threshold of D-BMI of 30 kg/m to decline donor offers for pancreas transplantation. However, no previous studies differentiate the impact of mild (D-BMI, 30-35 kg/m) versus severe obesity (D-BMI, ≥35 kg/m) on pancreas allograft outcomes. We examined Organ Procurement Transplant Network database records for 9916 simultaneous pancreas-kidney transplants (SPKT) performed between 2000 and 2013. We categorized donor body mass index (D-BMI) into 4 groups: 20 to 25 (n = 5724), 25 to 30 (n = 3303), 30 to 35 (n = 751), and 35 to 50 kg/m (n= 138). Associations of D-BMI with pancreas and kidney allograft failure were assessed by multivariate Cox regression adjusted for recipient, donor, and transplant factors. Compared with D-BMI 20 to 25 kg/m, only D-BMI 35 to 50 kg/m was associated with significantly higher pancreas allograft [adjusted hazard ratio [aHR], 1.37; 95% confidence interval (CI], 1.04-1.79] and kidney allograft (aHR, 1.36; CI, 1.02-1.82) failure over the study period (13 years). Donor BMI 30 to 35 kg/m did not impact pancreas allograft (aHR, 0.99; CI, 0.86-1.37) or kidney allograft (aHR, 0.98; CI, 0.84-1.15) failure. Similar patterns were noted at 3 months, and 1, 5, and 10 years posttransplant. These data support that pancreata from mildly obese donors (BMI, 30-35 kg/m) can be safely used for transplantation, with comparable short-term and long-term outcomes as organs from lean donors. Consideration of pancreata from obese donors may decrease the pancreas discard rate.

  4. MDCT evaluation of potential living renal donor, prior to laparoscopic donor nephrectomy: What the transplant surgeon wants to know?

    International Nuclear Information System (INIS)

    Ghonge, Nitin P; Gadanayak, Satyabrat; Rajakumari, Vijaya

    2014-01-01

    As Laparoscopic Donor Nephrectomy (LDN) offers several advantages for the donor such as lesser post-operative pain, fewer cosmetic concerns and faster recovery time, there is growing global trend towards LDN as compared to open nephrectomy. Comprehensive pre-LDN donor evaluation includes assessment of renal morphology including pelvi-calyceal and vascular system. Apart from donor selection, evaluation of the regional anatomy allows precise surgical planning. Due to limited visualization during laparoscopic renal harvesting, detailed pre-transplant evaluation of regional anatomy, including the renal venous anatomy is of utmost importance. MDCT is the modality of choice for pre-LDN evaluation of potential renal donors. Apart from appropriate scan protocol and post-processing methods, detailed understanding of surgical techniques is essential for the Radiologist for accurate image interpretation during pre-LDN MDCT evaluation of potential renal donors. This review article describes MDCT evaluation of potential living renal donor, prior to LDN with emphasis on scan protocol, post-processing methods and image interpretation. The article laid special emphasis on surgical perspectives of pre-LDN MDCT evaluation and addresses important points which transplant surgeons want to know

  5. Optimal tariff design under consumer self-selection

    Energy Technology Data Exchange (ETDEWEB)

    Raesaenen, M.; Ruusunen, J.; Haemaelaeinen, R.

    1995-12-31

    This report considers the design of electricity tariffs which guides an individual consumer to select the tariff designed for his consumption pattern. In the model the utility maximizes the weighted sum of individual consumers` benefits of electricity consumption subject to the utility`s revenue requirement constraints. The consumers` free choice of tariffs is ensured with the so-called self-selection constraints. The relationship between the consumers` optimal choice of tariffs and the weights in the aggregated consumers` benefit function is analyzed. If such weights exist, they will guarantee both the consumers` optimal choice of tariffs and the efficient consumption patterns. Also the welfare effects are analyzed by using demand parameters estimated from a Finnish dynamic pricing experiment. The results indicate that it is possible to design an efficient tariff menu with the welfare losses caused by the self-selection constraints being small compared with the costs created when some consumers choose tariffs other than assigned for them. (author)

  6. Living donor liver transplantation from a donor previously treated with interferon for hepatitis C virus: a case report

    Directory of Open Access Journals (Sweden)

    Nakao Kazuhiko

    2011-07-01

    Full Text Available Abstract Introduction Selecting a marginal donor in liver transplantation (LT remains controversial but is necessary because of the small number of available donors. Case presentation A 46-year-old Japanese woman was a candidate to donate her liver to her brother, who had decompensated liver cirrhosis of unknown origin. Eight years before the donation, she had a mild liver dysfunction that was diagnosed as a hepatitis C virus (HCV infection (serotype 2. She had received anti-viral therapy with interferon α-2b three times weekly for 24 weeks and had a sustained viral response (SVR. A biopsy of her liver before the donation showed normal findings without any active hepatitis, and her serum was negative for HCV-RNA. Only 67 patients have undergone LT from a cadaveric donor in Japan. The family in this case decided to have living donor LT. A careful selection for the liver graft donation was made; however, since she was the only candidate, we approved her as a living donor. She was discharged nine days after the liver donation. Her liver function recovered immediately. A computed tomography scan showed sufficient liver regeneration one year later. Her brother also had good liver function after LT and had no HCV infection 48 months after surgery and no de novo malignancy. Neither of the siblings has developed an HCV infection. Conclusions A patient with SVR status after interferon therapy might be considered a candidate for living donor LT but only if there are no other possibilities of LT for the recipient. A careful follow-up of the donor after donation is needed. The recipient also must have a very close follow-up because it is difficult to predict what might happen to the graft with post-transplant immunosuppression.

  7. Optimization of Liposomal Lipid Composition for a New, Reactive Sulfur Donor, and In Vivo Efficacy Studies on Mice to Antagonize Cyanide Intoxication

    Directory of Open Access Journals (Sweden)

    Ilona Petrikovics

    2011-01-01

    Full Text Available Present studies have focused on a novel cyanide antidotal system, on the coencapsulation of a new sulfur donor DTO with rhodanese within sterically stabilized liposomes. The optimal lipid composition for coencapsulation of DTO with rhodanese is the combination of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine, cholesterol, cationic lipid (DOTAP, and 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol-2000] ammonium salt (with molar ratios of 82.7 : 9.2 : 3.0 : 5.1. With the optimized compositions, prophylactic and therapeutic in vivo efficacy studies were carried out in a mice model. When DTO was coencapsulated with rhodanese and thiosulfate the prophylactic antidotal protection was 4.9×LD50. Maximum antidotal protection against cyanide intoxication (15×LD50 was achieved with coencapsulated rhodanese and DTO/thiosulfate in combination with sodium nitrite. When applied therapeutically, 100% survival rate (6/6 was achieved at 20 mg/kg cyanide doses with the encapsulated DTO-rhodanese-thiosulfate antidotal systems with and without sodium nitrite. These data are indicating that the appropriately formulated DTO is a promising sulfur donor for cyanide antagonism.

  8. Behavioral optimization models for multicriteria portfolio selection

    Directory of Open Access Journals (Sweden)

    Mehlawat Mukesh Kumar

    2013-01-01

    Full Text Available In this paper, behavioral construct of suitability is used to develop a multicriteria decision making framework for portfolio selection. To achieve this purpose, we rely on multiple methodologies. Analytical hierarchy process technique is used to model the suitability considerations with a view to obtaining the suitability performance score in respect of each asset. A fuzzy multiple criteria decision making method is used to obtain the financial quality score of each asset based upon investor's rating on the financial criteria. Two optimization models are developed for optimal asset allocation considering simultaneously financial and suitability criteria. An empirical study is conducted on randomly selected assets from National Stock Exchange, Mumbai, India to demonstrate the effectiveness of the proposed methodology.

  9. Scar evaluation of split thickness skin graft donor site

    Directory of Open Access Journals (Sweden)

    Jani Muha

    2014-12-01

    Full Text Available BACKGROUND. Split thickness skin graft harvesting causes a certain degree of scaring on the donor site. Donor site scar can cause aesthetic and functional sequelae on the patient's body. Our goal was to study the process of donor site selection, and then evaluate donor site scars and their impact on patients. PATIENTS AND METHODS. This retrospective study included 45 patients aged 5 to 61 years (in average 36, who have been treated with STSG in the 2004–2010 period. 57.8% of them were men. On a follow-up visit, we photographed healed skin defects and donor sites. We then determined and compared the surface areas of skin defect and the donor site using the Adobe® Illustrator® CS5 computer program. Donor site scars were assessed according to the Vancouver scar scale (VSS. We examined scar’s light touch sensitivity with monofilaments and skin colouring compared to adjacent healthy skin using colorimeter. Patients were also interviewed about their treatment course in a form of a standardized questionnaire. RESULTS. Our research has revealed that 20.0% of patients participated in the decision making process of choosing the donor site, while in 80.0% the donor site was chosen by the surgeon himself. 6.7% of patients were not satisfied with their donor site. Most of the patients (37/45 had donor sites on their thighs. In average, the donor site surface area was 94% bigger than the skin defect area. We found statistically significant differences in VSS values, light touch sensitivity and skin colouring between donor site scaring and adjacent healthy skin. CONCLUSIONS. Donor site scar can represent a lasting aesthetic and functional disability for patients. Our research has shown that most of the patients do not participate in the donor site selection process, but are satisfied with their donor site. In most cases, STGSs are harvested from the thigh, other anatomical regions, where scarring would be aesthetically less obtrusive, are underused

  10. Hepatic tissue environment in NEMO-deficient mice critically regulates positive selection of donor cells after hepatocyte transplantation.

    Directory of Open Access Journals (Sweden)

    Michaela Kaldenbach

    Full Text Available BACKGROUND: Hepatocyte transplantation (HT is a promising alternative treatment strategy for end-stage liver diseases compared with orthotopic liver transplantation. A limitation for this approach is the low engraftment of donor cells. The deletion of the I-kappa B kinase-regulatory subunit IKKγ/NEMO in hepatocytes prevents nuclear factor (NF-kB activation and triggers spontaneous liver apoptosis, chronic hepatitis and the development of liver fibrosis and hepatocellular carcinoma. We hypothesized that NEMOΔhepa mice may therefore serve as an experimental model to study HT. METHODS: Pre-conditioned NEMOΔhepa mice were transplanted with donor-hepatocytes from wildtype (WT and mice deficient for the pro-apoptotic mediator Caspase-8 (Casp8Δhepa. RESULTS: Transplantation of isolated WT-hepatocytes into pre-conditioned NEMOΔhepa mice resulted in a 6-7 fold increase of donor cells 12 weeks after HT, while WT-recipients showed no liver repopulation. The use of apoptosis-resistant Casp8Δhepa-derived donor cells further enhanced the selection 3-fold after 12-weeks and up to 10-fold increase after 52 weeks compared with WT donors. While analysis of NEMOΔhepa mice revealed strong liver injury, HT-recipient NEMOΔhepa mice showed improved liver morphology and decrease in serum transaminases. Concomitant with these findings, the histological examination elicited an improved liver tissue architecture associated with significantly lower levels of apoptosis, decreased proliferation and a lesser amount of liver fibrogenesis. Altogether, our data clearly support the therapeutic benefit of the HT procedure into NEMOΔhepa mice. CONCLUSION: This study demonstrates the feasibility of the NEMOΔhepa mouse as an in vivo tool to study liver repopulation after HT. The improvement of the characteristic phenotype of chronic liver injury in NEMOΔhepa mice after HT suggests the therapeutic potential of HT in liver diseases with a chronic inflammatory phenotype and

  11. [Outcome of living kidney donors for transplantation].

    Science.gov (United States)

    Lanot, Antoine; Bouvier, Nicolas; Chatelet, Valérie; Lecouf, Angélique; Tillou, Xavier; Hurault de Ligny, Bruno

    2017-11-01

    Nowadays, several treatments exist to treat terminal chronic renal failure. Best results for the recipients are obtained with kidney transplantation concerning mortality and quality of life. Transplantation is also the cheaper option for society. Living kidney donation raises the issue of the becoming of the donor, an absolutely healthy subject who gets to a surgical procedure. The becoming of living kidney donors has been compared with the one of controls subjects in several studies. The evaluations focused on the complications of nephrectomy in the short and long-term: kidney failure, hypertension, proteinuria, possibility of pregnancy, quality of life, and mortality. The first results did not show any risk linked to kidney donation, compared to general population. However, since 2013, kidney donors were found at higher risk for kidney failure and even for mortality, compared with controls selected like donor candidates. The risk of kidney donation is nevertheless acceptable and minimal, on the condition of rigorous selection of candidates and regular follow-up. Copyright © 2017 Société francophone de néphrologie, dialyse et transplantation. Published by Elsevier Masson SAS. All rights reserved.

  12. Analysis of blood donor pre-donation deferral in Dubai: characteristics and reasons

    Directory of Open Access Journals (Sweden)

    Al Shaer L

    2017-05-01

    Full Text Available Laila Al Shaer,1 Ranjita Sharma,2 Mahera AbdulRahman2 1College of Medicine, Mohammed Bin Rashid University of Medicine and Health Sciences, Dubai, UAE; 2Dubai Health Authority, Dubai, UAE Background: To ensure an adequate and safe blood supply, it is crucial to select suitable donors according to stringent eligibility criteria. Understanding the reasons for donor deferral can help in planning more efficient recruitment strategies and evaluating donor selection criteria. This study aims to define donor pre-donation deferral rates, causes of deferral, and characteristics of deferred donors in Dubai.Materials and methods: This retrospective study was conducted on all donors who presented for allogeneic blood donation between January 1, 2010, until June 30, 2013, in Dubai Blood Donation Centre, accredited by the American Association of Blood Banks. The donation and deferral data were analyzed to determine the demographic characteristics of accepted and deferred donors, and frequency analyses were also conducted.Results: Among 142,431 individuals presenting during the study period, 114,827 (80.6% were accepted for donation, and 27,604 (19.4% were deferred. The overall proportion of deferrals was higher among individuals less than 21 years old (35%, P<0.000, females (44% were deferred compared to 15% of males, P<0.0001, and first-time donors (22% were deferred vs 14% of repeat donors, P<0.0001. The main causes for a temporary deferral were low hemoglobin and high blood pressure.Discussion: The deferral rate among blood donors in Dubai is relatively high compared to the internationally reported rates. This rate was higher among first-time donors and females, with low hemoglobin as the major factor leading to a temporary deferral of donors. Strategies to mitigate deferral and improve blood donor retention are urged in Dubai to avoid additional stress on the blood supply. Keywords: blood donation, blood safety, donor deferral, selection criteria 

  13. Analysis of blood donor pre-donation deferral in Dubai: characteristics and reasons

    OpenAIRE

    Al Shaer, Laila; Sharma, Ranjita; AbdulRahman, Mahera

    2017-01-01

    Laila Al Shaer,1 Ranjita Sharma,2 Mahera AbdulRahman2 1College of Medicine, Mohammed Bin Rashid University of Medicine and Health Sciences, Dubai, UAE; 2Dubai Health Authority, Dubai, UAE Background: To ensure an adequate and safe blood supply, it is crucial to select suitable donors according to stringent eligibility criteria. Understanding the reasons for donor deferral can help in planning more efficient recruitment strategies and evaluating donor selection criteria. This study aims to def...

  14. Prevalence of HIV positive blood donors among screened ...

    African Journals Online (AJOL)

    Two thousand five hundred and thirty two (2,532) males, aged 25 – 50 years potential blood donors were randomly selected from the total number of volunteer blood donors who satisfied the initial screening criteria for donating blood, and were screened for HIV using Immunocomb II (HIV 1 and 2 Bispot) and Recombigen ...

  15. Donor-acceptor-donor thienyl/bithienyl-benzothiadiazole/quinoxaline model oligomers: experimental and theoretical studies.

    Science.gov (United States)

    Pina, João; de Melo, J Seixas; Breusov, D; Scherf, Ullrich

    2013-09-28

    A comprehensive spectral and photophysical investigation of four donor-acceptor-donor (DAD) oligomers consisting of electron-deficient 2,1,3-benzothiadiazole or quinoxaline moieties linked to electron-rich thienyl or bithienyl units has been undertaken. Additionally, a bis(dithienyl) substituted naphthalene was also investigated. The D-A-D nature of these oligomers resulted in the presence of an intramolecular charge transfer (ICT) state, which was further substantiated by solvatochromism studies (analysis with the Lippert-Mataga formalism). Hereby, significant differences have been obtained for the fluorescence quantum yields of the oligomers in the non-polar solvent methylcyclohexane vs. the polar ethanol. The study was further complemented with the determination of the optimized ground-state molecular geometries for the oligomers together with the prediction of the lowest vertical one-electron excitation energy and the relevant molecular orbital contours using DFT calculations. The electronic transitions show a clear HOMO to LUMO charge-transfer character. In contrast to the thiophene oligomers (the oligothiophenes with n = 1-7), where the intersystem crossing (ISC) yield decreases with n, the studied DAD oligomers were found to show an increase in the ISC efficiency with the number of (donor) thienyl units.

  16. Analysis of blood donor pre-donation deferral in Dubai: characteristics and reasons.

    Science.gov (United States)

    Al Shaer, Laila; Sharma, Ranjita; AbdulRahman, Mahera

    2017-01-01

    To ensure an adequate and safe blood supply, it is crucial to select suitable donors according to stringent eligibility criteria. Understanding the reasons for donor deferral can help in planning more efficient recruitment strategies and evaluating donor selection criteria. This study aims to define donor pre-donation deferral rates, causes of deferral, and characteristics of deferred donors in Dubai. This retrospective study was conducted on all donors who presented for allogeneic blood donation between January 1, 2010, until June 30, 2013, in Dubai Blood Donation Centre, accredited by the American Association of Blood Banks. The donation and deferral data were analyzed to determine the demographic characteristics of accepted and deferred donors, and frequency analyses were also conducted. Among 142,431 individuals presenting during the study period, 114,827 (80.6%) were accepted for donation, and 27,604 (19.4%) were deferred. The overall proportion of deferrals was higher among individuals less than 21 years old (35%, P Dubai is relatively high compared to the internationally reported rates. This rate was higher among first-time donors and females, with low hemoglobin as the major factor leading to a temporary deferral of donors. Strategies to mitigate deferral and improve blood donor retention are urged in Dubai to avoid additional stress on the blood supply.

  17. MDCT evaluation of potential living renal donor, prior to laparoscopic donor nephrectomy: What the transplant surgeon wants to know?

    Directory of Open Access Journals (Sweden)

    Nitin P Ghonge

    2014-01-01

    Full Text Available As Laparoscopic Donor Nephrectomy (LDN offers several advantages for the donor such as lesser post-operative pain, fewer cosmetic concerns and faster recovery time, there is growing global trend towards LDN as compared to open nephrectomy. Comprehensive pre-LDN donor evaluation includes assessment of renal morphology including pelvi-calyceal and vascular system. Apart from donor selection, evaluation of the regional anatomy allows precise surgical planning. Due to limited visualization during laparoscopic renal harvesting, detailed pre-transplant evaluation of regional anatomy, including the renal venous anatomy is of utmost importance. MDCT is the modality of choice for pre-LDN evaluation of potential renal donors. Apart from appropriate scan protocol and post-processing methods, detailed understanding of surgical techniques is essential for the Radiologist for accurate image interpretation during pre-LDN MDCT evaluation of potential renal donors. This review article describes MDCT evaluation of potential living renal donor, prior to LDN with emphasis on scan protocol, post-processing methods and image interpretation. The article laid special emphasis on surgical perspectives of pre-LDN MDCT evaluation and addresses important points which transplant surgeons want to know.

  18. Thiophene dendrimer-based low donor content solar cells

    Science.gov (United States)

    Stoltzfus, Dani M.; Ma, Chang-Qi; Nagiri, Ravi C. R.; Clulow, Andrew J.; Bäuerle, Peter; Burn, Paul L.; Gentle, Ian R.; Meredith, Paul

    2016-09-01

    Low donor content solar cells containing polymeric and non-polymeric donors blended with fullerenes have been reported to give rise to efficient devices. In this letter, we report that a dendrimeric donor can also be used in solution-processed low donor content devices when blended with a fullerene. A third generation dendrimer containing 42 thiophene units (42T) was found to give power conversion efficiencies of up to 3.5% when blended with PC70BM in optimized devices. The best efficiency was measured with 10 mole percent (mol. %) of 42T in PC70BM and X-ray reflectometry showed that the blends were uniform. Importantly, while 42T comprised 10 mol. % of the film, it made up 31% of the film by volume. Finally, it was found that solvent annealing was required to achieve the largest open circuit voltage and highest device efficiencies.

  19. Anonymous living liver donation: donor profiles and outcomes.

    Science.gov (United States)

    Reichman, T W; Fox, A; Adcock, L; Wright, L; Abbey, S E; Levy, G; Grant, D R

    2010-09-01

    There are no published series of the assessment process, profiles and outcomes of anonymous, directed or nondirected live liver donation. The outcomes of 29 consecutive potential anonymous liver donors at our center were assessed. We used our standard live liver assessment process, augmented with the following additional acceptance criteria: a logical rationale for donation, a history of social altruism, strong social supports and a willingness to maintain confidentiality of patient information. Seventeen potential donors were rejected and 12 donors were ultimately accepted (six male, six female). All donors were strongly motivated by a desire and sense of responsibility to help others. Four donations were directed toward recipients who undertook media appeals. The donor operations included five left lateral segmentectomies and seven right hepatectomies. The overall donor morbidity was 40% with one patient having a transient Clavien level 3 complication (a pneumothorax). All donors are currently well. None expressed regret about their decision to donate, and all volunteered the opinion that donation had improved their lives. The standard live liver donor assessment process plus our additional requirements appears to provide a robust assessment process for the selection of anonymous live liver donors. Acceptance of anonymous donors enlarges the donor liver pool. © 2010 The Authors Journal compilation © 2010 The American Society of Transplantation and the American Society of Transplant Surgeons.

  20. Donor-derived infections in solid organ transplant patients: toward a holistic approach.

    Science.gov (United States)

    Benamu, Esther; Wolfe, Cameron R; Montoya, José G

    2017-08-01

    Solid organ demand far exceeds organ supply. Strategies to increase the donor pool include the liberalization of selection criteria without increasing the risk of unexpected donor-derived infection (DDI), a rare complication of transplantation carrying high morbidity and mortality. We review the challenging aspects in the prevention of DDI, focusing on the complexities of data sharing and efficient communication and the role infectious diseases specialists play in the process. Advances in donor screening, transmission recognition and reporting allow for a better estimation of the risk of DDI. However, there is great variability in the frequency and methods with which organ procurement organizations report transmission events.Moreover, the Scientific Registry of Transplant Recipients provides limited donor and recipient outcome infectious diseases related data. Infectious disease contribution to the allocation process has been found to improve organ donation efficiency and communication between involved parties. Although communication gaps are strongly associated with infection transmission (relative risk 2.36%, confidence interval 1.48-3.78), effective communication minimizes or prevents infection in transplant recipients (X(1) 13.13, P = 0.0003). Prospective research is still required to define optimal screening protocols and further prevent transmission of infection. A holistic approach is likely to result in enhanced transplantation safety. Toward this goal, development of standards of investigation; improvement in reporting and data sharing; and strategies ensuring coordinated and rapid communication among parties involved in the allocation process need to be pursued.

  1. Optimal Sensor Selection for Health Monitoring Systems

    Science.gov (United States)

    Santi, L. Michael; Sowers, T. Shane; Aguilar, Robert B.

    2005-01-01

    Sensor data are the basis for performance and health assessment of most complex systems. Careful selection and implementation of sensors is critical to enable high fidelity system health assessment. A model-based procedure that systematically selects an optimal sensor suite for overall health assessment of a designated host system is described. This procedure, termed the Systematic Sensor Selection Strategy (S4), was developed at NASA John H. Glenn Research Center in order to enhance design phase planning and preparations for in-space propulsion health management systems (HMS). Information and capabilities required to utilize the S4 approach in support of design phase development of robust health diagnostics are outlined. A merit metric that quantifies diagnostic performance and overall risk reduction potential of individual sensor suites is introduced. The conceptual foundation for this merit metric is presented and the algorithmic organization of the S4 optimization process is described. Representative results from S4 analyses of a boost stage rocket engine previously under development as part of NASA's Next Generation Launch Technology (NGLT) program are presented.

  2. Training set optimization under population structure in genomic selection.

    Science.gov (United States)

    Isidro, Julio; Jannink, Jean-Luc; Akdemir, Deniz; Poland, Jesse; Heslot, Nicolas; Sorrells, Mark E

    2015-01-01

    Population structure must be evaluated before optimization of the training set population. Maximizing the phenotypic variance captured by the training set is important for optimal performance. The optimization of the training set (TRS) in genomic selection has received much interest in both animal and plant breeding, because it is critical to the accuracy of the prediction models. In this study, five different TRS sampling algorithms, stratified sampling, mean of the coefficient of determination (CDmean), mean of predictor error variance (PEVmean), stratified CDmean (StratCDmean) and random sampling, were evaluated for prediction accuracy in the presence of different levels of population structure. In the presence of population structure, the most phenotypic variation captured by a sampling method in the TRS is desirable. The wheat dataset showed mild population structure, and CDmean and stratified CDmean methods showed the highest accuracies for all the traits except for test weight and heading date. The rice dataset had strong population structure and the approach based on stratified sampling showed the highest accuracies for all traits. In general, CDmean minimized the relationship between genotypes in the TRS, maximizing the relationship between TRS and the test set. This makes it suitable as an optimization criterion for long-term selection. Our results indicated that the best selection criterion used to optimize the TRS seems to depend on the interaction of trait architecture and population structure.

  3. Robotic-Assisted Live Donor Ileal Segmentectomy for Intestinal Transplantation

    Directory of Open Access Journals (Sweden)

    Guosheng Wu, MD, PhD

    2017-10-01

    Full Text Available Background. Every effort should be made to optimize surgical techniques and to minimize potential morbidity rates associated with live donor operations. Advances in a minimally invasive approach by robotic surgery to donor nephrectomy have raised the possibility of applying this technique to live donor bowel resections for intestinal transplantation. Methods. We report the first 5 consecutive cases of a robotic-assisted live donor ileal segmentectomy. We describe the technical aspects of the procedure, discuss the rationale for considering this option, and evaluate potential advantages of this approach. Results. We found that this new approach is associated with less postoperative discomfort, a shorter hospital length of stay, and a faster recovery of bowel function compared to our previous open surgery. Conclusions. Our initial experience suggests that robotic surgery is a safe and feasible procedure for live donor ileal resection for intestinal transplantation and is a useful alternative to conventional open surgery.

  4. Dechlorinating ability of TCE-fed microcosms with different electron donors

    International Nuclear Information System (INIS)

    Panagiotakis, Iraklis; Mamais, Daniel; Pantazidou, Marina; Marneri, Matina; Parapouli, Maria; Hatziloukas, Efstathios; Tandoi, Valter

    2007-01-01

    The main objective of the work presented herein is to assess the effect of different electron donors (butyric acid and methanol) on the dechlorinating activity of two microbial cultures where active methanogenic populations are present, in an effort to evaluate the importance of the electron donor selection process. The ability of each anaerobic culture to dechlorinate TCE, when enriched with either butyric acid or methanol, was verified based on the results of gas chromatography. In addition, the fluorescent in situ hybridization (FISH) and the polymerase chain reaction (PCR) methods gave positive results for the presence of Dehalococcoides spp. According to results of the batch tests conducted in this study, it appears that the selection of the electron donor for stimulating TCE dechlorination depends on microbial culture composition; therefore, the decision on the appropriate electron donor should be based on site-specific microcosm studies

  5. Optimal infrastructure selection to boost regional sustainable economy

    OpenAIRE

    Martín Utrillas, Manuel Guzmán; Juan-Garcia, F.; Cantó Perelló, Julián; Curiel Esparza, Jorge

    2015-01-01

    The role of infrastructures in boosting the economic growth of the regions is widely recognized. In many cases, an infrastructure is selected by subjective reasons. Selection of the optimal infrastructure for sustainable economic development of a region should be based on objective and founded reasons, not only economical, but also environmental and social. In this paper is developed such selection through a hybrid method based on Delphi, analytical hierarchy process (AHP), and VIKOR (from Se...

  6. Optimal Contracting under Adverse Selection

    DEFF Research Database (Denmark)

    Lenells, Jonatan; Stea, Diego; Foss, Nicolai Juul

    2015-01-01

    We study a model of adverse selection, hard and soft information, and mentalizing ability--the human capacity to represent others' intentions, knowledge, and beliefs. By allowing for a continuous range of different information types, as well as for different means of acquiring information, we dev...... of that information. This strategy affects the properties of the optimal contract, which grows closer to the first best. This research provides insights into the implications of mentalizing for agency theory....

  7. Donor Outcomes in Living Donor Liver Transplantation-Analysis of 275 Donors From a Single Centre in India.

    Science.gov (United States)

    Narasimhan, Gomathy; Safwan, Mohamed; Kota, Venugopal; Reddy, Mettu S; Bharathan, Anand; Dabora, Abderrhaim; Kaliamoorthy, Ilankumaran; Kanagavelu, Rathnavel G; Srinivasan, Vijaya; Rela, Mohamed

    2016-06-01

    Live donor liver transplantation is the predominant form of liver transplantation in India and in most Asian countries. Donor outcome reports are an important source of information to be shared with prospective donors at the time of informed consent. This is the first donor outcome series from India. Analysis of donor characteristics and morbidity of 275 live donors from a single large volume center is documented. Two hundred seventy-five patients donated from November 2009 to October 2014, 144 were women and 131 were men, 180 donated to adults and 95 donated to children. Right lobe donors were majority at 62.2% followed by left lateral segment 28%. Two thirds of the live donors did not have any morbidity; 114 complications were encountered in 85 patients. The complications were graded as per Clavien 5 tier grading and major morbidity (grade III b, grade IV grade V) was 4.36%. Postoperative biliary complication was seen in 3 donors. This large single-center study is the first donor outcome report from India, and the results are comparable to other published donor series. Documentation and regular audit of donor outcomes is important to help improve the safety of donor hepatectomy and to provide a database for informed consent of prospective donors.

  8. Are live kidney donors at risk

    International Nuclear Information System (INIS)

    Kamran, T.; Zaheer, K.; Hussain, S.W.; Zahid, K.H.; Akhtar, M.S.

    2003-01-01

    Objective: To share experience of live donor nephrectomy (including intraoperative variables, morbidity and ethical aspects) and to give an overview of surgical technique being practiced. Results: Majority of the donors (58.5%) were 31-50 years old and 70.6% were first-degree relatives. Left sided kidney was taken in 96.5% cases. Mean operative time was 145 minutes. Mean renal warm ischemia time from cross clamping of renal vessels to cold perfusion on the bench was 1.5 minutes per operation. Operative complications encountered were injury to lumbar veins in 5.1 % cases, slipping of satinsky clamp on vena cava stump in 1.7 % and accidental pleural damage in 5.1 % cases. Postoperative morbid complications found were urinary retention in 6.4 % cases, epididymo-orchitis in 1.7 %, prolonged lymph drain in 3.4 %, stitch infection in 1.7 % and prolonged wound discomfort in 5.1 % patients. Conclusions: Open live donor nepherectomy appears to be safe procedure for harvesting kidney. Related or emotionally related donors must be the choice in all cases. Non-related donors may be entertained in selected cases despite the probability of organ vending in our society. (author)

  9. Breast milk donors in France: a portrait of the typical donor and the utility of milk banking in the French breastfeeding context.

    Science.gov (United States)

    Azema, Emilie; Callahan, Stacey

    2003-05-01

    Although information regarding attitudes and characteristics of human blood donors has been researched, little is known about the motivations and demographic and personality characteristics of women who choose to donate their breast milk. Eight milk banks in France participated in a study examining donor characteristics, providing data on 103 women. The results showed that the donors were women of average childbearing age with strong support at home. Almost half did not work outside of the home, compared to the national average of 80% of women in this age group; similarly, a large number (currently working or not) were from the health and social services fields. Reasons for donation were largely altruistic, and a general optimistic attitude prevailed within the participants. The results of this study provide useful information for the recruitment of potential donors as well as information on how to facilitate and provide optimal service through milk donation.

  10. Selection of donor platelets for alloimmunized patients using a platelet-associated IgG assay

    International Nuclear Information System (INIS)

    Myers, T.J.; Kim, B.K.; Steiner, M.; Baldini, M.G.

    1981-01-01

    A quantitative immunofluorescence platelet-associated immunoglobulin-G (PA-IgG) assay was used to detect alloimmunity to platelets in 8/12 multitransfused patients and to perform platelet crossmatching in the 8 alloimmunized patients. The correct separation of multitransfused patients into alloimmune and nonalloimmune groups was substantiated with chromium-51-labeled platelet survival studies. For 5 alloimmunized patients, compatible and incompatible donor platelets were demonstrated by PA-IgG crossmatching and were confirmed by platelet survival studies. With the other 3 alloimmunized patients, only Pa-IgG incompatible donor platelets were found. Survival studies with 5 of these incompatible donor platelets showed markedly reduced survival times on 4 occasions. Pa-IgG compatible donor platelets survived 3.5 to 8.7 days, while Pa-IgG incompatible platelets showed survival times of 0.1 to 2.4 days

  11. Discrete Biogeography Based Optimization for Feature Selection in Molecular Signatures.

    Science.gov (United States)

    Liu, Bo; Tian, Meihong; Zhang, Chunhua; Li, Xiangtao

    2015-04-01

    Biomarker discovery from high-dimensional data is a complex task in the development of efficient cancer diagnoses and classification. However, these data are usually redundant and noisy, and only a subset of them present distinct profiles for different classes of samples. Thus, selecting high discriminative genes from gene expression data has become increasingly interesting in the field of bioinformatics. In this paper, a discrete biogeography based optimization is proposed to select the good subset of informative gene relevant to the classification. In the proposed algorithm, firstly, the fisher-markov selector is used to choose fixed number of gene data. Secondly, to make biogeography based optimization suitable for the feature selection problem; discrete migration model and discrete mutation model are proposed to balance the exploration and exploitation ability. Then, discrete biogeography based optimization, as we called DBBO, is proposed by integrating discrete migration model and discrete mutation model. Finally, the DBBO method is used for feature selection, and three classifiers are used as the classifier with the 10 fold cross-validation method. In order to show the effective and efficiency of the algorithm, the proposed algorithm is tested on four breast cancer dataset benchmarks. Comparison with genetic algorithm, particle swarm optimization, differential evolution algorithm and hybrid biogeography based optimization, experimental results demonstrate that the proposed method is better or at least comparable with previous method from literature when considering the quality of the solutions obtained. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Assessment of potential heart donors: A statement from the French heart transplant community.

    Science.gov (United States)

    Dorent, Richard; Gandjbakhch, Estelle; Goéminne, Céline; Ivanes, Fabrice; Sebbag, Laurent; Bauer, Fabrice; Epailly, Eric; Boissonnat, Pascale; Nubret, Karine; Amour, Julien; Vermes, Emmanuelle; Ou, Phalla; Guendouz, Soulef; Chevalier, Philippe; Lebreton, Guillaume; Flecher, Erwan; Obadia, Jean-François; Logeart, Damien; de Groote, Pascal

    2018-02-01

    Assessment of potential donors is an essential part of heart transplantation. Despite the shortage of donor hearts, donor heart procurement from brain-dead organ donors remains low in France, which may be explained by the increasing proportion of high-risk donors, as well as the mismatch between donor assessment and the transplant team's expectations. Improving donor and donor heart assessment is essential to improve the low utilization rate of available donor hearts without increasing post-transplant recipient mortality. This document provides information to practitioners involved in brain-dead donor management, evaluation and selection, concerning the place of medical history, electrocardiography, cardiac imaging, biomarkers and haemodynamic and arrhythmia assessment in the characterization of potential heart donors. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  13. Compensatory Analysis and Optimization for MADM for Heterogeneous Wireless Network Selection

    Directory of Open Access Journals (Sweden)

    Jian Zhou

    2016-01-01

    Full Text Available In the next-generation heterogeneous wireless networks, a mobile terminal with a multi-interface may have network access from different service providers using various technologies. In spite of this heterogeneity, seamless intersystem mobility is a mandatory requirement. One of the major challenges for seamless mobility is the creation of a network selection scheme, which is for users that select an optimal network with best comprehensive performance between different types of networks. However, the optimal network may be not the most reasonable one due to compensation of MADM (Multiple Attribute Decision Making, and the network is called pseudo-optimal network. This paper conducts a performance evaluation of a number of widely used MADM-based methods for network selection that aim to keep the mobile users always best connected anywhere and anytime, where subjective weight and objective weight are all considered. The performance analysis shows that the selection scheme based on MEW (weighted multiplicative method and combination weight can better avoid accessing pseudo-optimal network for balancing network load and reducing ping-pong effect in comparison with three other MADM solutions.

  14. Accumulation of GC donor splice signals in mammals

    Directory of Open Access Journals (Sweden)

    Koonin Eugene V

    2008-07-01

    Full Text Available Abstract The GT dinucleotide in the first two intron positions is the most conserved element of the U2 donor splice signals. However, in a small fraction of donor sites, GT is replaced by GC. A substantial enrichment of GC in donor sites of alternatively spliced genes has been observed previously in human, nematode and Arabidopsis, suggesting that GC signals are important for regulation of alternative splicing. We used parsimony analysis to reconstruct evolution of donor splice sites and inferred 298 GT > GC conversion events compared to 40 GC > GT conversion events in primate and rodent genomes. Thus, there was substantive accumulation of GC donor splice sites during the evolution of mammals. Accumulation of GC sites might have been driven by selection for alternative splicing. Reviewers This article was reviewed by Jerzy Jurka and Anton Nekrutenko. For the full reviews, please go to the Reviewers' Reports section.

  15. Optimal set of selected uranium enrichments that minimizes blending consequences

    International Nuclear Information System (INIS)

    Nachlas, J.A.; Kurstedt, H.A. Jr.; Lobber, J.S. Jr.

    1977-01-01

    Identities, quantities, and costs associated with producing a set of selected enrichments and blending them to provide fuel for existing reactors are investigated using an optimization model constructed with appropriate constraints. Selected enrichments are required for either nuclear reactor fuel standardization or potential uranium enrichment alternatives such as the gas centrifuge. Using a mixed-integer linear program, the model minimizes present worth costs for a 39-product-enrichment reference case. For four ingredients, the marginal blending cost is only 0.18% of the total direct production cost. Natural uranium is not an optimal blending ingredient. Optimal values reappear in most sets of ingredient enrichments

  16. The impact of meeting donor management goals on the number of organs transplanted per expanded criteria donor: a prospective study from the UNOS Region 5 Donor Management Goals Workgroup.

    Science.gov (United States)

    Patel, Madhukar S; Zatarain, John; De La Cruz, Salvador; Sally, Mitchell B; Ewing, Tyler; Crutchfield, Megan; Enestvedt, C Kristian; Malinoski, Darren J

    2014-09-01

    The shortage of organs available for transplant has led to the use of expanded criteria donors (ECDs) to extend the donor pool. These donors are older and have more comorbidities and efforts to optimize the quality of their organs are needed. To determine the impact of meeting a standardized set of critical care end points, or donor management goals (DMGs), on the number of organs transplanted per donor in ECDs. Prospective interventional study from February 2010 to July 2013 of all ECDs managed by the 8 organ procurement organizations in the southwestern United States (United Network for Organ Sharing Region 5). Implementation of 9 DMGs as a checklist to guide the management of every ECD. The DMGs represented normal cardiovascular, pulmonary, renal, and endocrine end points. Meeting the DMG bundle was defined a priori as achieving any 7 of the 9 end points and was recorded at the time of referral to the organ procurement organization, at the time of authorization for donation, 12 to 18 hours later, and prior to organ recovery. The primary outcome measure was 3 or more organs transplanted per donor and binary logistic regression was used to identify independent predictors with P organs transplanted per donor. Ten percent of the ECDs had met the DMG bundle at referral, 15% at the time of authorization, 33% at 12 to 18 hours, and 45% prior to recovery. Forty-three percent had 3 or more organs transplanted per donor. Independent predictors of 3 or more organs transplanted per donor were older age (odds ratio [OR] = 0.95 per year [95% CI, 0.93-0.97]), increased creatinine level (OR = 0.73 per mg/dL [95% CI, 0.63-0.85]), DMGs met prior to organ recovery (OR = 1.90 [95% CI, 1.35-2.68]), and a change in the number of DMGs achieved from referral to organ recovery (OR = 1.11 per additional DMG [95% CI, 1.00-1.23]). Meeting DMGs prior to organ recovery with ECDs is associated with achieving 3 or more organs transplanted per donor. An increase in the number

  17. Optimized Power Allocation and Relay Location Selection in Cooperative Relay Networks

    Directory of Open Access Journals (Sweden)

    Jianrong Bao

    2017-01-01

    Full Text Available An incremental selection hybrid decode-amplify forward (ISHDAF scheme for the two-hop single relay systems and a relay selection strategy based on the hybrid decode-amplify-and-forward (HDAF scheme for the multirelay systems are proposed along with an optimized power allocation for the Internet of Thing (IoT. Given total power as the constraint and outage probability as an objective function, the proposed scheme possesses good power efficiency better than the equal power allocation. By the ISHDAF scheme and HDAF relay selection strategy, an optimized power allocation for both the source and relay nodes is obtained, as well as an effective reduction of outage probability. In addition, the optimal relay location for maximizing the gain of the proposed algorithm is also investigated and designed. Simulation results show that, in both single relay and multirelay selection systems, some outage probability gains by the proposed scheme can be obtained. In the comparison of the optimized power allocation scheme with the equal power allocation one, nearly 0.1695 gains are obtained in the ISHDAF single relay network at a total power of 2 dB, and about 0.083 gains are obtained in the HDAF relay selection system with 2 relays at a total power of 2 dB.

  18. Optimality Theory and Lexical Interpretation and Selection

    NARCIS (Netherlands)

    Hogeweg, L.; Legendre, G.; Putnam, M.T.; de Swart, H.; Zaroukian, E.

    2016-01-01

    This chapter argues for an optimization approach to the selection and interpretation of words. Several advantages of such an approach to lexical semantics are discussed. First of all, it will be argued that competition, entailing that words and interpretations are always judged in relation to other

  19. Optimizing Event Selection with the Random Grid Search

    Energy Technology Data Exchange (ETDEWEB)

    Bhat, Pushpalatha C. [Fermilab; Prosper, Harrison B. [Florida State U.; Sekmen, Sezen [Kyungpook Natl. U.; Stewart, Chip [Broad Inst., Cambridge

    2017-06-29

    The random grid search (RGS) is a simple, but efficient, stochastic algorithm to find optimal cuts that was developed in the context of the search for the top quark at Fermilab in the mid-1990s. The algorithm, and associated code, have been enhanced recently with the introduction of two new cut types, one of which has been successfully used in searches for supersymmetry at the Large Hadron Collider. The RGS optimization algorithm is described along with the recent developments, which are illustrated with two examples from particle physics. One explores the optimization of the selection of vector boson fusion events in the four-lepton decay mode of the Higgs boson and the other optimizes SUSY searches using boosted objects and the razor variables.

  20. The New Multipoint Relays Selection in OLSR using Particle Swarm Optimization

    Directory of Open Access Journals (Sweden)

    Razali Ngah

    2012-06-01

    Full Text Available The standard Optimized Link State Routing (OLSR introduces an interesting concept, the multipoint relays (MPRs, to mitigate message overhead during the flooding process. We propose a new algorithm for MPRs selection to enhance the performance of OLSR using Particle Swarm Optimization Sigmoid Increasing Inertia Weight (PSOSIIW. The sigmoid increasing inertia weight has significance improve the particle swarm optimization (PSO in terms of simplicity and quick convergence towards optimum solution. The new fitness function of PSO-SIIW, packet delay of each node and degree of willingness are introduced to support MPRs selection in OLSR. We examine the throughput, packet loss and end-to-end delay of the proposed method using network simulator 2 (ns2.  Overall results indicate that OLSR-PSOSIIW has shown good performance compared to the standard OLSR and OLSR-PSO, particularly for the throughput and end-to-end delay. Generally the proposed OLSR-PSOSIIW shows advantage of using PSO for optimizing routing paths in the MPRs selection algorithm.

  1. Adaptive feature selection using v-shaped binary particle swarm optimization.

    Science.gov (United States)

    Teng, Xuyang; Dong, Hongbin; Zhou, Xiurong

    2017-01-01

    Feature selection is an important preprocessing method in machine learning and data mining. This process can be used not only to reduce the amount of data to be analyzed but also to build models with stronger interpretability based on fewer features. Traditional feature selection methods evaluate the dependency and redundancy of features separately, which leads to a lack of measurement of their combined effect. Moreover, a greedy search considers only the optimization of the current round and thus cannot be a global search. To evaluate the combined effect of different subsets in the entire feature space, an adaptive feature selection method based on V-shaped binary particle swarm optimization is proposed. In this method, the fitness function is constructed using the correlation information entropy. Feature subsets are regarded as individuals in a population, and the feature space is searched using V-shaped binary particle swarm optimization. The above procedure overcomes the hard constraint on the number of features, enables the combined evaluation of each subset as a whole, and improves the search ability of conventional binary particle swarm optimization. The proposed algorithm is an adaptive method with respect to the number of feature subsets. The experimental results show the advantages of optimizing the feature subsets using the V-shaped transfer function and confirm the effectiveness and efficiency of the feature subsets obtained under different classifiers.

  2. CHAPTER 3. High-performance Organic Photovoltaic Donor Polymers

    KAUST Repository

    Wadsworth, Andrew

    2017-11-08

    The field of organic photovoltaics has advanced a great deal over the last decade, with device efficiencies now exceeding 11%. A large part of this success can be attributed to the development of donor polymer materials, from their humble beginnings as homopolymers to the highly tuned push-pull copolymer and terpolymer materials that are now being reported on a regular basis. Through the careful use of chemical modification, it has been possible to design and synthesize a wide variety of donor polymers, allowing optimization of both the optoelectronic and structural properties of the materials. In doing so, more favourable active layer blends have been achieved and therefore significant improvements in device performance have been observed. Herein we discuss how the chemical design of donor polymers for organic photovoltaics has led to the emergence of high-performance materials.

  3. CHAPTER 3. High-performance Organic Photovoltaic Donor Polymers

    KAUST Repository

    Wadsworth, Andrew; Baran, Derya; Gorman, Jeffrey; McCulloch, Iain

    2017-01-01

    The field of organic photovoltaics has advanced a great deal over the last decade, with device efficiencies now exceeding 11%. A large part of this success can be attributed to the development of donor polymer materials, from their humble beginnings as homopolymers to the highly tuned push-pull copolymer and terpolymer materials that are now being reported on a regular basis. Through the careful use of chemical modification, it has been possible to design and synthesize a wide variety of donor polymers, allowing optimization of both the optoelectronic and structural properties of the materials. In doing so, more favourable active layer blends have been achieved and therefore significant improvements in device performance have been observed. Herein we discuss how the chemical design of donor polymers for organic photovoltaics has led to the emergence of high-performance materials.

  4. Selective and non-extractive spectrophotometric determination of cefdinir in formulations based on donor-acceptor complex formation

    Directory of Open Access Journals (Sweden)

    Babita K. Singh

    2010-01-01

    Full Text Available Cefdinir has broad spectrum of activity and high prescription rates, hence its counterfeiting seems imminent. We have proposed a simple, fast, selective and non-extractive spectrophotometric method for the content assay of cefdinir in formulations. The method is based on complexation of cefdinir and Fe under reducing condition in a buffered medium (pH 11 to form a magenta colored donor-acceptor complex (λ max = 550 nm; apparent molar absorptivity = 3720 L mol-1 cm-1. No other cephalosporins, penicillins and common excipients interfere under the test conditions. The Beer's law is followed in the concentration range 8-160 µg mL-1.

  5. Parameter Optimization for Selected Correlation Analysis of Intracranial Pathophysiology

    Directory of Open Access Journals (Sweden)

    Rupert Faltermeier

    2015-01-01

    Full Text Available Recently we proposed a mathematical tool set, called selected correlation analysis, that reliably detects positive and negative correlations between arterial blood pressure (ABP and intracranial pressure (ICP. Such correlations are associated with severe impairment of the cerebral autoregulation and intracranial compliance, as predicted by a mathematical model. The time resolved selected correlation analysis is based on a windowing technique combined with Fourier-based coherence calculations and therefore depends on several parameters. For real time application of this method at an ICU it is inevitable to adjust this mathematical tool for high sensitivity and distinct reliability. In this study, we will introduce a method to optimize the parameters of the selected correlation analysis by correlating an index, called selected correlation positive (SCP, with the outcome of the patients represented by the Glasgow Outcome Scale (GOS. For that purpose, the data of twenty-five patients were used to calculate the SCP value for each patient and multitude of feasible parameter sets of the selected correlation analysis. It could be shown that an optimized set of parameters is able to improve the sensitivity of the method by a factor greater than four in comparison to our first analyses.

  6. Parameter Optimization for Selected Correlation Analysis of Intracranial Pathophysiology.

    Science.gov (United States)

    Faltermeier, Rupert; Proescholdt, Martin A; Bele, Sylvia; Brawanski, Alexander

    2015-01-01

    Recently we proposed a mathematical tool set, called selected correlation analysis, that reliably detects positive and negative correlations between arterial blood pressure (ABP) and intracranial pressure (ICP). Such correlations are associated with severe impairment of the cerebral autoregulation and intracranial compliance, as predicted by a mathematical model. The time resolved selected correlation analysis is based on a windowing technique combined with Fourier-based coherence calculations and therefore depends on several parameters. For real time application of this method at an ICU it is inevitable to adjust this mathematical tool for high sensitivity and distinct reliability. In this study, we will introduce a method to optimize the parameters of the selected correlation analysis by correlating an index, called selected correlation positive (SCP), with the outcome of the patients represented by the Glasgow Outcome Scale (GOS). For that purpose, the data of twenty-five patients were used to calculate the SCP value for each patient and multitude of feasible parameter sets of the selected correlation analysis. It could be shown that an optimized set of parameters is able to improve the sensitivity of the method by a factor greater than four in comparison to our first analyses.

  7. Nanographenes as electron-deficient cores of donor-acceptor systems.

    Science.gov (United States)

    Liu, Yu-Min; Hou, Hao; Zhou, Yan-Zhen; Zhao, Xin-Jing; Tang, Chun; Tan, Yuan-Zhi; Müllen, Klaus

    2018-05-15

    Conjugation of nanographenes (NGs) with electro-active molecules can establish donor-acceptor π-systems in which the former generally serve as the electron-donating moieties due to their electronic-rich nature. In contrast, here we report a series of reversed donor-acceptor structures are obtained by C-N coupling of electron-deficient perchlorinated NGs with electron-rich anilines. Selective amination at the vertexes of the NGs is unambiguously shown through X-ray crystallography. By varying the donating ability of the anilino groups, the optical and assembly properties of donor-acceptor NGs can be finely modulated. The electron-deficient concave core of the resulting conjugates can host electron-rich guest molecules by intermolecular donor-acceptor interactions and gives rise to charge-transfer supramolecular architectures.

  8. [Evaluation of the efficacy of medical screening of blood donors on preventing blood transfusion-transmitted infectious agents].

    Science.gov (United States)

    Seck, M; Dièye, B; Guèye, Y B; Faye, B F; Senghor, A B; Toure, S A; Dieng, N; Sall, A; Toure, A O; Dièye, T N; Diop, S

    2016-05-01

    The aim of this study was to evaluate the efficacy of medical screening to retain blood donors in window period by comparing the seroprevalence of infectious agents (HIV, hepatitis B and C, syphilis) in deferred versus accepted blood donors. This prospective and transversal study was performed during 4 months in the National Blood Transfusion Center in Dakar (Senegal). We conducted a convenience sampling comparing the seroprevalence of infectious agents (HIV, HBsAg, HCV and syphilis) in deferred versus accepted blood donors after medical selection. In total, 8219 blood donors were included. Medical selection had authorized 8048 donors (97.92%) and deferred donors were 171 (2.08%). The prevalence of HIV was higher in the deferred than in accepted blood donors (1.75% vs. 0.05%) (P=0.0003; OR=35.91), as well as for HBsAg (12.87% vs. 7.35%) (P=0.006; OR=1.86). HCV antibodies were present in 0.71% of accepted blood donors and 0.58% in deferred blood donors (P=0.65; OR=0.82). Only accepted donors had brought the infection of syphilis (0.34%) (P=0.56; OR=0). Medical selection is efficient to exclude blood donors at high risk of HIV transmission and to a lesser extent of HBV. However, current medical screening procedures do not allow us to exclude donors asymptomatic carriers of HCV and syphilis. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  9. Review of randomized clinical trials of donor management and organ preservation in deceased donors: opportunities and issues.

    Science.gov (United States)

    Dikdan, George S; Mora-Esteves, Cesar; Koneru, Baburao

    2012-09-15

    Given the static number of deceased donors, improvements in donor management and organ preservation to increase the number and quality of organs transplanted per donor are more pressing. Because controlled trials provide the best evidence, we conducted a review of English-language literature of trials in donor management and organ preservation to provide a compendium and to promote additional discussion and studies. Eighty-seven reports were retrieved: 13 on hemodynamic and fluid management, 7 on immunosuppressants, 12 on preconditioning, 34 on preservation fluids, and 21 on pulsatile perfusion. Sixteen studies are ongoing. Although hormonal therapy is used widely, additional studies are needed to determine the benefit of thyroid hormone and insulin replacement and to optimize steroid regimens. Dopamine's success in reducing kidney delayed graft function highlights the opportunity for additional preconditioning trials of remote ischemia, gases, opioids, and others. More rapid progress requires addressing unique barriers in consent and research approval, legal constraints precluding research in cardiac death donors, and streamlining collaboration of multiple stakeholders. With little interest from industry, federal funding needs to be increased. While the University of Wisconsin solution still reigns supreme, several promising preservative solutions and additives with not only biophysical but also pharmacological effects are on the cusp of phase 1 to 2 trials. After nearly three decades of uncertainty, the recent success of a European trial has reenergized the topic not only of machine preservation of the kidney but also of other organs evident by trials in progress. However, the costs of such technical innovations merit the burden of rigorous proof from controlled trials.

  10. Optimized Policies for Improving Fairness of Location-based Relay Selection

    DEFF Research Database (Denmark)

    Nielsen, Jimmy Jessen; Olsen, Rasmus Løvenstein; Madsen, Tatiana Kozlova

    2013-01-01

    For WLAN systems in which relaying is used to improve throughput performance for nodes located at the cell edge, node mobility and information collection delays can have a significant impact on the performance of a relay selection scheme. In this paper we extend our existing Markov Chain modeling...... framework for relay selection to allow for efficient calculation of relay policies given either mean throughput or kth throughput percentile as optimization criterium. In a scenario with static access point, static relay, and a mobile destination node, the kth throughput percentile optimization...

  11. Selection on Optimal Haploid Value Increases Genetic Gain and Preserves More Genetic Diversity Relative to Genomic Selection.

    Science.gov (United States)

    Daetwyler, Hans D; Hayden, Matthew J; Spangenberg, German C; Hayes, Ben J

    2015-08-01

    Doubled haploids are routinely created and phenotypically selected in plant breeding programs to accelerate the breeding cycle. Genomic selection, which makes use of both phenotypes and genotypes, has been shown to further improve genetic gain through prediction of performance before or without phenotypic characterization of novel germplasm. Additional opportunities exist to combine genomic prediction methods with the creation of doubled haploids. Here we propose an extension to genomic selection, optimal haploid value (OHV) selection, which predicts the best doubled haploid that can be produced from a segregating plant. This method focuses selection on the haplotype and optimizes the breeding program toward its end goal of generating an elite fixed line. We rigorously tested OHV selection breeding programs, using computer simulation, and show that it results in up to 0.6 standard deviations more genetic gain than genomic selection. At the same time, OHV selection preserved a substantially greater amount of genetic diversity in the population than genomic selection, which is important to achieve long-term genetic gain in breeding populations. Copyright © 2015 by the Genetics Society of America.

  12. Quantum dot laser optimization: selectively doped layers

    Science.gov (United States)

    Korenev, Vladimir V.; Konoplev, Sergey S.; Savelyev, Artem V.; Shernyakov, Yurii M.; Maximov, Mikhail V.; Zhukov, Alexey E.

    2016-08-01

    Edge emitting quantum dot (QD) lasers are discussed. It has been recently proposed to use modulation p-doping of the layers that are adjacent to QD layers in order to control QD's charge state. Experimentally it has been proven useful to enhance ground state lasing and suppress the onset of excited state lasing at high injection. These results have been also confirmed with numerical calculations involving solution of drift-diffusion equations. However, deep understanding of physical reasons for such behavior and laser optimization requires analytical approaches to the problem. In this paper, under a set of assumptions we provide an analytical model that explains major effects of selective p-doping. Capture rates of elections and holes can be calculated by solving Poisson equations for electrons and holes around the charged QD layer. The charge itself is ruled by capture rates and selective doping concentration. We analyzed this self-consistent set of equations and showed that it can be used to optimize QD laser performance and to explain underlying physics.

  13. Quantum dot laser optimization: selectively doped layers

    International Nuclear Information System (INIS)

    Korenev, Vladimir V; Konoplev, Sergey S; Savelyev, Artem V; Shernyakov, Yurii M; Maximov, Mikhail V; Zhukov, Alexey E

    2016-01-01

    Edge emitting quantum dot (QD) lasers are discussed. It has been recently proposed to use modulation p-doping of the layers that are adjacent to QD layers in order to control QD's charge state. Experimentally it has been proven useful to enhance ground state lasing and suppress the onset of excited state lasing at high injection. These results have been also confirmed with numerical calculations involving solution of drift-diffusion equations. However, deep understanding of physical reasons for such behavior and laser optimization requires analytical approaches to the problem. In this paper, under a set of assumptions we provide an analytical model that explains major effects of selective p-doping. Capture rates of elections and holes can be calculated by solving Poisson equations for electrons and holes around the charged QD layer. The charge itself is ruled by capture rates and selective doping concentration. We analyzed this self-consistent set of equations and showed that it can be used to optimize QD laser performance and to explain underlying physics. (paper)

  14. A parallel optimization method for product configuration and supplier selection based on interval

    Science.gov (United States)

    Zheng, Jian; Zhang, Meng; Li, Guoxi

    2017-06-01

    In the process of design and manufacturing, product configuration is an important way of product development, and supplier selection is an essential component of supply chain management. To reduce the risk of procurement and maximize the profits of enterprises, this study proposes to combine the product configuration and supplier selection, and express the multiple uncertainties as interval numbers. An integrated optimization model of interval product configuration and supplier selection was established, and NSGA-II was put forward to locate the Pareto-optimal solutions to the interval multiobjective optimization model.

  15. Role of Killer Immunoglobulin-Like Receptor and Ligand Matching in Donor Selection

    Directory of Open Access Journals (Sweden)

    Meral Beksaç

    2012-01-01

    Full Text Available Despite all efforts to improve HLA typing and immunosuppression, it is still impossible to prevent severe graft versus host disease (GVHD which can be fatal. GVHD is not always associated with graft versus malignancy and can prevent stem cell transplantation from reaching its goals. Overall T-cell alloreactivity is not the sole mechanism modulating the immune defense. Innate immune system has its own antigens, ligands, and mediators. The bridge between HLA and natural killer (NK cell-mediated reactions is becoming better understood in the context of stem cell transplantation. Killer immunoglobulin-like receptors (KIRs constitute a wide range of alleles/antigens segregated independently from the HLA alleles and classified into two major haplotypes which imprints the person's ability to suppress or to amplify T-cell alloreactivity. This paper will summarize the impact of both activating and inhibitory KIRs and their ligands on stem cell transplantation outcome. The ultimate goal is to develop algorithms based on KIR profiles to select donors with maximum antileukemic and minimum antihost effects.

  16. Pharmacists' guide to the management of organ donors after brain death.

    Science.gov (United States)

    Korte, Catherine; Garber, Jennifer L; Descourouez, Jillian L; Richards, Katelyn R; Hardinger, Karen

    2016-11-15

    This article reviews organ donor pathophysiology as it relates to medication use with the goal of maximizing the successful procurement and transplantation of donor organs. The number of patients requiring organ transplantation continues to grow, yet organ donation rates remain flat, making it critical to appropriately manage each organ donor in order to ensure viability of all transplantable organs. The care given to one organ donor is tantamount to the care of several transplant recipients. Aggressive donor management ensures that the largest number of organs can be successfully procured and improves the organs' overall quality. Hospital pharmacists are responsible for processing orders and preparing the medications outlined in donor management algorithms developed by their respective medical systems. It is important that pharmacists understand the details of the medications used in these protocols in order to critically evaluate each medication order and appropriately manage the donor. Typical medications used in organ donors after brain death include medications for blood pressure management and fluid resuscitation, medications necessary for electrolyte management, blood products, vasopressors, hormone replacement therapy, antiinfectives, anticoagulants, paralytics, and organ preservation solutions. It is essential to provide optimal pharmacotherapy for each organ donor to ensure organ recovery and donation. Typical medications used in organ donors include agents for blood pressure management and fluid resuscitation, medications necessary for electrolyte management, blood products, vasopressors, hormone replacement therapy, antiinfectives, anticoagulants, paralytics, and organ preservation solutions. Copyright © 2016 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

  17. Are drowned donors marginal donors? A single pediatric center experience.

    Science.gov (United States)

    Kumm, Kayla R; Galván, N Thao N; Koohmaraie, Sarah; Rana, Abbas; Kueht, Michael; Baugh, Katherine; Hao, Liu; Yoeli, Dor; Cotton, Ronald; O'Mahony, Christine A; Goss, John A

    2017-09-01

    Drowning, a common cause of death in the pediatric population, is a potentially large donor pool for OLT. Anecdotally, transplant centers have deemed these organs high risk over concerns for infection and graft dysfunction. We theorized drowned donor liver allografts do not portend worse outcomes and therefore should not be excluded from the donation pool. We reviewed our single-center experience of pediatric OLTs between 1988 and 2015 and identified 33 drowned donor recipients. These OLTs were matched 1:2 to head trauma donor OLTs from our center. A chart review assessed postoperative peak AST and ALT, incidence of HAT, graft and recipient survival. Recipient survival at one year between patients with drowned donor vs head trauma donor allografts was not statistically significant (94% vs 97%, P=.63). HAT incidence was 6.1% in the drowned donor group vs 7.6% in the control group (P=.78). Mean postoperative peak AST and ALT was 683 U/L and 450 U/L for drowned donors vs 1119 U/L and 828 U/L in the matched cohort. These results suggest drowned donor liver allografts do not portend worse outcomes in comparison with those procured from head trauma donors. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  18. A game-theoretic approach to donor kidney sharing.

    Science.gov (United States)

    O'Brien, B J

    1988-01-01

    Graft survival in renal transplantation is a function, amongst other things, of the degree of histocompatibility lymphocyte-A (HLA) tissue matching achieved between donor and recipient. Yet a donor procured at centre A might match a transplant candidate at centre B and vice versa. This raises the question of whether, and under what circumstances, surgeons will offer and exchange donor kidneys and gain from such trade in terms of graft survival. We analyse the problem in a game-theoretic framework where the choice of strategy 'to offer or not?' is evaluated in the context of the uncertainty of reciprocation by the other player(s) in the game. The equilibrium solution to a number of variations of the game is predicted to be non-cooperation resulting in collectively sub-optimal graft survival rates. Some policy options for improving cooperation are considered including exchange incentives and coercive measures.

  19. Determination of Dornic acidity as a method to select donor milk in a milk bank.

    Science.gov (United States)

    Vázquez-Román, Sara; Garcia-Lara, Nadia Raquel; Escuder-Vieco, Diana; Chaves-Sánchez, Fernando; De la Cruz-Bertolo, Javier; Pallas-Alonso, Carmen Rosa

    2013-02-01

    Dornic acidity may be an indirect measurement of milk's bacteria content and its quality. There are no uniform criteria among different human milk banks on milk acceptance criteria. The main aim of this study is to report the correlation between Dornic acidity and bacterial growth in donor milk in order to validate the Dornic acidity value as an adequate method to select milk prior to its pasteurization. From 105 pools, 4-mL samples of human milk were collected. Dornic acidity measurement and culture in blood and McConkey's agar cultures were performed. Based on Dornic acidity degrees, we classified milk into three quality categories: top quality (acidity pasteurize in a human milk bank based in quality and safety criteria.

  20. Optimizing the allocation of resources for genomic selection in one breeding cycle.

    Science.gov (United States)

    Riedelsheimer, Christian; Melchinger, Albrecht E

    2013-11-01

    We developed a universally applicable planning tool for optimizing the allocation of resources for one cycle of genomic selection in a biparental population. The framework combines selection theory with constraint numerical optimization and considers genotype  ×  environment interactions. Genomic selection (GS) is increasingly implemented in plant breeding programs to increase selection gain but little is known how to optimally allocate the resources under a given budget. We investigated this problem with model calculations by combining quantitative genetic selection theory with constraint numerical optimization. We assumed one selection cycle where both the training and prediction sets comprised double haploid (DH) lines from the same biparental population. Grain yield for testcrosses of maize DH lines was used as a model trait but all parameters can be adjusted in a freely available software implementation. An extension of the expected selection accuracy given by Daetwyler et al. (2008) was developed to correctly balance between the number of environments for phenotyping the training set and its population size in the presence of genotype × environment interactions. Under small budget, genotyping costs mainly determine whether GS is superior over phenotypic selection. With increasing budget, flexibility in resource allocation increases greatly but selection gain leveled off quickly requiring balancing the number of populations with the budget spent for each population. The use of an index combining phenotypic and GS predicted values in the training set was especially beneficial under limited resources and large genotype × environment interactions. Once a sufficiently high selection accuracy is achieved in the prediction set, further selection gain can be achieved most efficiently by massively expanding its size. Thus, with increasing budget, reducing the costs for producing a DH line becomes increasingly crucial for successfully exploiting the

  1. AHP-Based Optimal Selection of Garment Sizes for Online Shopping

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Garment online shopping has been accepted by more and more consumers in recent years. In online shopping, a buyer only chooses the garment size judged by his own experience without trying-on, so the selected garment may not be the fittest one for the buyer due to the variety of body's figures. Thus, we propose a method of optimal selection of garment sizes for online shopping based on Analytic Hierarchy Process (AHP). The hierarchical structure model for optimal selection of garment sizes is structured and the fittest garment for a buyer is found by calculating the matching degrees between individual's measurements and the corresponding key-part values of ready-to-wear clothing sizes. In order to demonstrate its feasibility, we provide an example of selecting the fittest sizes of men's bottom. The result shows that the proposed method is useful in online clothing sales application.

  2. [Acceptance by blood donors of the public blood bank in Recife, Brazil].

    Science.gov (United States)

    de Araújo, Fábia Michelle Rodrigues; Feliciano, Katia Virginia de Oliveira; Mendes, Marina Ferreira de Medeiros

    2011-12-01

    This study evaluated the acceptance of blood donors concerning the donation stages (attendance, medical and nursing selection and collection) at the Recife public blood bank with emphasis on the attendance. A sample of 527 donors was obtained: each 19th person sequentially was invited to answer a questionnaire. Chi-square (x2) was used in the analysis. Of those interviewed, 81.4% were men, 81% were repeat donors, 50.3% were dissatisfied regarding the time spent in donation and 36.4% had difficulties in reaching the service. The firm acceptance given to the attendance was due mainly to the communication and the quality of treatment. Of statistical significance were women donors of higher educational level who asked for more information and men who had a more positive perception towards the selection process. The best evaluation was attributed to the collection sector. However, mention was made of impersonal treatment, persistence of doubts and the cursory nature of the medical interview. Attention focused on the donor requires that ongoing education should concentrate on the humanitarian formation of the professionals involved.

  3. Gamete donation: parents' experiences of searching for their child's donor siblings and donor.

    Science.gov (United States)

    Freeman, T; Jadva, V; Kramer, W; Golombok, S

    2009-03-01

    This study investigates the new phenomenon of parents of donor offspring searching for and contacting their child's 'donor siblings' (i.e. donor offspring conceived by the same donor) and donor. Online questionnaires were completed by 791 parents (39% lone-mother, 35% lesbian-couple, 21% heterosexual-couple, 5% non-specified) recruited via the Donor Sibling Registry; a US-based international registry that facilitates contact between donor conception families who share the same donor. Data were collected on parents' reasons for searching for their child's donor siblings and/or donor, the outcome of these searches and parents' and their child's experiences of any resulting contact. Parents' principal motivation for searching for their child's donor siblings was curiosity and for their donor, enhancing their child's sense of identity. Some parents had discovered large numbers of donor siblings (maximum = 55). Most parents reported positive experiences of contacting and meeting their child's donor siblings and donor. This study highlights that having access to information about a child's donor origins is important for some parents and has potentially positive consequences. These findings have wider implications because the removal of donor anonymity in the UK and elsewhere means that increasing numbers of donor offspring are likely to seek contact with their donor relations in the future.

  4. Selecting Optimal Subset of Security Controls

    OpenAIRE

    Yevseyeva, I.; Basto-Fernandes, V.; Michael, Emmerich, T. M.; Moorsel, van, A.

    2015-01-01

    Open Access journal Choosing an optimal investment in information security is an issue most companies face these days. Which security controls to buy to protect the IT system of a company in the best way? Selecting a subset of security controls among many available ones can be seen as a resource allocation problem that should take into account conflicting objectives and constraints of the problem. In particular, the security of the system should be improved without hindering productivity, ...

  5. Transport spectroscopy of coupled donors in silicon nano-transistors

    Science.gov (United States)

    Moraru, Daniel; Samanta, Arup; Anh, Le The; Mizuno, Takeshi; Mizuta, Hiroshi; Tabe, Michiharu

    2014-01-01

    The impact of dopant atoms in transistor functionality has significantly changed over the past few decades. In downscaled transistors, discrete dopants with uncontrolled positions and number induce fluctuations in device operation. On the other hand, by gaining access to tunneling through individual dopants, a new type of devices is developed: dopant-atom-based transistors. So far, most studies report transport through dopants randomly located in the channel. However, for practical applications, it is critical to control the location of the donors with simple techniques. Here, we fabricate silicon transistors with selectively nanoscale-doped channels using nano-lithography and thermal-diffusion doping processes. Coupled phosphorus donors form a quantum dot with the ground state split into a number of levels practically equal to the number of coupled donors, when the number of donors is small. Tunneling-transport spectroscopy reveals fine features which can be correlated with the different numbers of donors inside the quantum dot, as also suggested by first-principles simulation results. PMID:25164032

  6. Diet selection of African elephant over time shows changing optimization currency

    NARCIS (Netherlands)

    Pretorius, Y.; Stigter, J.D.; Boer, de W.F.; Wieren, van S.E.; Jong, de C.B.; Knegt, de H.J.; Grant, R.C.; Heitkonig, I.M.A.; Knox, N.; Kohi, E.; Mwakiwa, E.; Peel, M.J.S.; Skidmore, A.K.; Slotow, R.; Waal, van der C.; Langevelde, van F.; Prins, H.H.T.

    2012-01-01

    Multiple factors determine diet selection of herbivores. However, in many diet studies selection of single nutrients is studied or optimization models are developed using only one currency. In this paper, we use linear programming to explain diet selection by African elephant based on plant

  7. Optimal Parameter Selection of Power System Stabilizer using Genetic Algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Hyeng Hwan; Chung, Dong Il; Chung, Mun Kyu [Dong-AUniversity (Korea); Wang, Yong Peel [Canterbury Univeristy (New Zealand)

    1999-06-01

    In this paper, it is suggested that the selection method of optimal parameter of power system stabilizer (PSS) with robustness in low frequency oscillation for power system using real variable elitism genetic algorithm (RVEGA). The optimal parameters were selected in the case of power system stabilizer with one lead compensator, and two lead compensator. Also, the frequency responses characteristics of PSS, the system eigenvalues criterion and the dynamic characteristics were considered in the normal load and the heavy load, which proved usefulness of RVEGA compare with Yu's compensator design theory. (author). 20 refs., 15 figs., 8 tabs.

  8. Selective Segmentation for Global Optimization of Depth Estimation in Complex Scenes

    Directory of Open Access Journals (Sweden)

    Sheng Liu

    2013-01-01

    Full Text Available This paper proposes a segmentation-based global optimization method for depth estimation. Firstly, for obtaining accurate matching cost, the original local stereo matching approach based on self-adapting matching window is integrated with two matching cost optimization strategies aiming at handling both borders and occlusion regions. Secondly, we employ a comprehensive smooth term to satisfy diverse smoothness request in real scene. Thirdly, a selective segmentation term is used for enforcing the plane trend constraints selectively on the corresponding segments to further improve the accuracy of depth results from object level. Experiments on the Middlebury image pairs show that the proposed global optimization approach is considerably competitive with other state-of-the-art matching approaches.

  9. Living renal donors: optimizing the imaging strategy--decision- and cost-effectiveness analysis

    NARCIS (Netherlands)

    Y.S. Liem (Ylian Serina); M.C.J.M. Kock (Marc); W. Weimar (Willem); K. Visser (Karen); M.G.M. Hunink (Myriam); J.N.M. IJzermans (Jan)

    2003-01-01

    textabstractPURPOSE: To determine the most cost-effective strategy for preoperative imaging performed in potential living renal donors. MATERIALS AND METHODS: In a decision-analytic model, the societal cost-effectiveness of digital subtraction angiography (DSA), gadolinium-enhanced

  10. Statistical and optimal learning with applications in business analytics

    Science.gov (United States)

    Han, Bin

    Statistical learning is widely used in business analytics to discover structure or exploit patterns from historical data, and build models that capture relationships between an outcome of interest and a set of variables. Optimal learning on the other hand, solves the operational side of the problem, by iterating between decision making and data acquisition/learning. All too often the two problems go hand-in-hand, which exhibit a feedback loop between statistics and optimization. We apply this statistical/optimal learning concept on a context of fundraising marketing campaign problem arising in many non-profit organizations. Many such organizations use direct-mail marketing to cultivate one-time donors and convert them into recurring contributors. Cultivated donors generate much more revenue than new donors, but also lapse with time, making it important to steadily draw in new cultivations. The direct-mail budget is limited, but better-designed mailings can improve success rates without increasing costs. We first apply statistical learning to analyze the effectiveness of several design approaches used in practice, based on a massive dataset covering 8.6 million direct-mail communications with donors to the American Red Cross during 2009-2011. We find evidence that mailed appeals are more effective when they emphasize disaster preparedness and training efforts over post-disaster cleanup. Including small cards that affirm donors' identity as Red Cross supporters is an effective strategy, while including gift items such as address labels is not. Finally, very recent acquisitions are more likely to respond to appeals that ask them to contribute an amount similar to their most recent donation, but this approach has an adverse effect on donors with a longer history. We show via simulation that a simple design strategy based on these insights has potential to improve success rates from 5.4% to 8.1%. Given these findings, when new scenario arises, however, new data need to

  11. Comparing prevalence of Iron Deficiency Anemia and Beta Thalassemia Trait in microcytic and non-microcytic blood donors: suggested algorithm for donor screening

    Directory of Open Access Journals (Sweden)

    Tiwari Aseem

    2009-01-01

    Full Text Available Background: The prevalence of microcytosis in donors and Iron Deficiency Anemia (IDA and Beta-Thalassemia trait (BTT in microcytic and non-microcytic donors has not been studied in India. The present study aims at finding the same. Materials and Methods: Initially 925 donor samples were evaluated on cell-counter. Of these, 50 were found to be microcytic. These were subjected to Ferritin and HbA2 determination. Subsequently, an additional 51, age-and-sex matched non-microcytic donor samples were selected to serve as controls. These were subjected to the same tests. Results: The prevalence of microcytosis was 5.4% (50/925. Among the microcytic donors, 52% were IDA, 36% BTT, 8% both, and 4% none. In case of non-microcytic donors 29.4% were IDA, 3.9% BTT, and 66.7% none. Conclusions: The study revealed a high prevalence of IDA and BTT in blood donors and a higher probability of finding these in the microcytic samples. This prompted authors to suggest an algorithm for screening of blood donors for IDA and BTT. The algorithm recommends doing an hemogram on all donor samples, routinely. Ferritin could be done only in microcytic samples. At levels lower than15 ng/ml, it is diagnosed as IDA, and therefore, HPLC is performed only for non-IDA samples with Ferritin levels higher than 15 ng/ml. By employing this algorithm, a substantial number of IDA and BTT could be diagnosed while keeping the number of Ferritin tests small and the number of HPLC tests even smaller and thus making it cost efficient.

  12. Control of charge transfer by conformational and electronic effects: Donor-donor and donor-acceptor phenyl pyrroles

    International Nuclear Information System (INIS)

    Neubauer, Antje; Bendig, Juergen; Rettig, Wolfgang

    2009-01-01

    Derivatives of N-pyrrolobenzene with a para-donor and a para-acceptor substituent on the benzene ring are compared. It is shown that by a suitable increase of the donor strength of the pyrrolo group, CT fluorescence can be achieved even for donor-donor-substituted benzenes. The ICT emission for sterically hindered compounds is more forbidden than that of unhindered phenyl pyrroles. This suggests conformational effects which induce a narrower twist angle distribution around a perpendicular minimum in the excited state.

  13. Clinical effects of blood donor characteristics in transfusion recipients: protocol of a framework to study the blood donor-recipient continuum.

    Science.gov (United States)

    Chassé, Michaël; McIntyre, Lauralyn; Tinmouth, Alan; Acker, Jason; English, Shane W; Knoll, Greg; Forster, Alan; Shehata, Nadine; Wilson, Kumanan; van Walraven, Carl; Ducharme, Robin; Fergusson, Dean A

    2015-01-19

    When used appropriately, transfusion of red blood cells (RBCs) is a necessary life-saving therapy. However, RBC transfusions have been associated with negative outcomes such as infection and organ damage. Seeking explanations for the beneficial and deleterious effects of RBC transfusions is necessary to ensure the safe and optimal use of this precious resource. This study will create a framework to analyse the influence of blood donor characteristics on recipient outcomes. We will conduct a multisite, longitudinal cohort study using blood donor data routinely collected by Canadian Blood Services, and recipient data from health administrative databases. Our project will include a thorough validation of primary data, the linkage of various databases into one large longitudinal database, an in-depth epidemiological analysis and a careful interpretation and dissemination of the results to assist the decision-making process of clinicians, researchers and policymakers in transfusion medicine. Our primary donor characteristic will be age of blood donors and our secondary donor characteristics will be donor-recipient blood group compatibility and blood donor sex. Our primary recipient outcome will be a statistically appropriate survival analysis post-RBC transfusion up to a maximum of 8 years. Our secondary recipient outcomes will include 1-year, 2-year and 5-year mortality; hospital and intensive care unit length of stay; rehospitalisation; new cancer and cancer recurrence rate; infection rate; new occurrence of myocardial infarctions and need for haemodialysis. Our results will help determine whether we need to tailor transfusion based on donor characteristics, and perhaps this will improve patient outcome. Our results will be customised to target the different stakeholders involved with blood transfusions and will include presentations, peer-reviewed publications and the use of the dissemination network of blood supply organisations. We obtained approval from the

  14. Alternative donor transplantation--"mixing and matching": the role of combined cord blood and haplo-identical donor transplantation (haplo-cord SCT) as a treatment strategy for patients lacking standard donors?

    Science.gov (United States)

    Liu, Hongtao; van Besien, Koen

    2015-03-01

    In the past decade, haplo-cord stem cell transplantation (SCT) using myeloablative or reduced intensive conditioning regimens has been shown to result in reliable and fast engraftment of neutrophils and platelets comparable to HLA-matched donors and much faster than after cord stem cell transplant. Haplo-cord SCT also has a low incidence of early non-relapse mortality, low incidences of acute and chronic graft-vs-host disease (GVHD), and excellent graft-vs-leukemia (GVL) effects. Favorable long-term outcomes for high-risk patients with hematologic malignancies have been reported, including older patients. Haplo-cord SCT will likely overcome the limitations of cell dose during cord stem cell selection and might significantly expand the use of cord stem cell transplant in the adult population. The comparable survival outcomes of matched related donor (MRD), matched unrelated donor (MUD), and haplo-cord stem cell transplant strongly argue that haplo-cord SCT should be considered as effective alternative stem cell transplant for high-risk patients lacking standard donors. Further improvement in supportive care and incorporation of a better understanding of the human fetal immune development into the haplo-cord SCT are required to further improve this strategy.

  15. [Automated serial diagnosis of donor blood samples. Ergonomic and economic organization structure].

    Science.gov (United States)

    Stoll, T; Fischer-Fröhlich, C L; Mayer, G; Hanfland, P

    1990-01-01

    A comprehensive computer-aided administration-system for blood-donors is presented. Ciphered informations of barcode-labels allow the automatic and nevertheless selective pipetting of samples by pipetting-robots. Self-acting analysis-results are transferred to a host-computer in order to actualize a donor data-base.

  16. Simulation and Optimization of Control of Selected Phases of Gyroplane Flight

    Directory of Open Access Journals (Sweden)

    Wienczyslaw Stalewski

    2018-02-01

    Full Text Available Optimization methods are increasingly used to solve problems in aeronautical engineering. Typically, optimization methods are utilized in the design of an aircraft airframe or its structure. The presented study is focused on improvement of aircraft flight control procedures through numerical optimization. The optimization problems concern selected phases of flight of a light gyroplane—a rotorcraft using an unpowered rotor in autorotation to develop lift and an engine-powered propeller to provide thrust. An original methodology of computational simulation of rotorcraft flight was developed and implemented. In this approach the aircraft motion equations are solved step-by-step, simultaneously with the solution of the Unsteady Reynolds-Averaged Navier–Stokes equations, which is conducted to assess aerodynamic forces acting on the aircraft. As a numerical optimization method, the BFGS (Broyden–Fletcher–Goldfarb–Shanno algorithm was adapted. The developed methodology was applied to optimize the flight control procedures in selected stages of gyroplane flight in direct proximity to the ground, where proper control of the aircraft is critical to ensure flight safety and performance. The results of conducted computational optimizations proved the qualitative correctness of the developed methodology. The research results can be helpful in the design of easy-to-control gyroplanes and also in the training of pilots for this type of rotorcraft.

  17. The Living Donor Lost Wages Trial: Study Rationale and Protocol.

    Science.gov (United States)

    Rodrigue, James R; Fleishman, Aaron; Carroll, Michaela; Evenson, Amy R; Pavlakis, Martha; Mandelbrot, Didier A; Baliga, Prabhakar; Howard, David H; Schold, Jesse D

    2018-03-01

    This paper describes the background, rationale, and design of an NIH-funded, single-center study to test the impact of offering reimbursement for donor lost wages incurred during the post-nephrectomy recovery period on the live donor kidney transplant (LDKT) rate in newly evaluated kidney transplant candidates, to examine whether offering reimbursement for donor lost wages reduces racial disparity in LDKT rates, and to determine whether higher reimbursement amounts lead to higher LDKT rates. LDKT is the optimal treatment for renal failure. However, living kidney donation has declined in the past decade, particularly among men, younger adults, blacks, and low-income adults. There is evidence that donation-related costs may deter both transplant candidates and potential donors from considering LDKT. Lost wages is a major source of financial loss for some living donors and, unlike travel and lodging expenses, is not reimbursed by financial assistance programs. The study addresses the transplant community's call to reduce the financial burden of living donation and examine its impact on LDKT rates. Findings have the potential to influence policy, clinical practice, LDKT access, and income-related and racial disparities in LDKT and living donation.

  18. An opinion formation based binary optimization approach for feature selection

    Science.gov (United States)

    Hamedmoghadam, Homayoun; Jalili, Mahdi; Yu, Xinghuo

    2018-02-01

    This paper proposed a novel optimization method based on opinion formation in complex network systems. The proposed optimization technique mimics human-human interaction mechanism based on a mathematical model derived from social sciences. Our method encodes a subset of selected features to the opinion of an artificial agent and simulates the opinion formation process among a population of agents to solve the feature selection problem. The agents interact using an underlying interaction network structure and get into consensus in their opinions, while finding better solutions to the problem. A number of mechanisms are employed to avoid getting trapped in local minima. We compare the performance of the proposed method with a number of classical population-based optimization methods and a state-of-the-art opinion formation based method. Our experiments on a number of high dimensional datasets reveal outperformance of the proposed algorithm over others.

  19. Increasing the pool of deceased donor organs for kidney transplantation.

    Science.gov (United States)

    Schold, Jesse D; Segev, Dorry L

    2012-03-27

    Expanding the pool of available deceased donor kidneys is critical for improving the outcomes of prospective and current renal transplant candidates. A number of interventions have been proposed that may increase the pool of donors in the US. However, these interventions have variable levels of empirical evidence supporting their potential beneficial impact. Proposed interventions include the instigation of policies for presumed donor consent, the expansion of donor registration, increased quality oversight of transplant providers, financial incentives for donors, increased reimbursement for higher risk donors, alterations in organ allocation policies and distribution, and the selective use of donors with potential or known risk for disease transmission. Many of these interventions have contentious elements that may have delayed or impeded their implementation; however, these options should be considered in the context of the diminishing prognoses for prospective transplant patients, given the increasing scarcity of donor organs relative to the population need. In this Review, we outline the proposed interventions and briefly discuss salient issues that characterize the debates concerning their implementation and effectiveness. Ultimately, any intervention must be based on the best evidence available, with consideration of numerous stakeholders and in conjunction with a careful evaluation of long-term and potential unintended consequences.

  20. Experiences of offspring searching for and contacting their donor siblings and donor.

    Science.gov (United States)

    Jadva, Vasanti; Freeman, Tabitha; Kramer, Wendy; Golombok, Susan

    2010-04-01

    This study investigates a new phenomenon whereby individuals conceived by donor insemination are searching for and contacting their donor and/or 'donor siblings' (i.e. donor offspring conceived by the same donor who are their genetic half siblings). On-line questionnaires were completed by members of the Donor Sibling Registry (DSR), a US-based registry that facilitates contact between donor conception families who share the same donor. Of the 165 donor offspring who completed the survey, 15% were searching for their donor siblings, 13% were searching for their donor, and 64% were searching for both. Differences were found according to family type and age of disclosure. Fewer offspring from heterosexual couple families had told their father about their search when compared with offspring from lesbian couple families who had told their co-parent. Offspring who had found out about their conception after age 18 were more likely to be searching for medical reasons, whereas those who had found out before age 18 tended to be searching out of curiosity. Some offspring had discovered large numbers of half siblings (maximum=13). The majority of offspring who had found their donor relations reported positive experiences and remained in regular contact with them. Copyright (c) 2010 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  1. Partner Selection Optimization Model of Agricultural Enterprises in Supply Chain

    OpenAIRE

    Feipeng Guo; Qibei Lu

    2013-01-01

    With more and more importance of correctly selecting partners in supply chain of agricultural enterprises, a large number of partner evaluation techniques are widely used in the field of agricultural science research. This study established a partner selection model to optimize the issue of agricultural supply chain partner selection. Firstly, it constructed a comprehensive evaluation index system after analyzing the real characteristics of agricultural supply chain. Secondly, a heuristic met...

  2. Opportunistic relaying in multipath and slow fading channel: Relay selection and optimal relay selection period

    KAUST Repository

    Sungjoon Park,

    2011-11-01

    In this paper we present opportunistic relay communication strategies of decode and forward relaying. The channel that we are considering includes pathloss, shadowing, and fast fading effects. We find a simple outage probability formula for opportunistic relaying in the channel, and validate the results by comparing it with the exact outage probability. Also, we suggest a new relay selection algorithm that incorporates shadowing. We consider a protocol of broadcasting the channel gain of the previously selected relay. This saves resources in slow fading channel by reducing collisions in relay selection. We further investigate the optimal relay selection period to maximize the throughput while avoiding selection overhead. © 2011 IEEE.

  3. Selection and optimization of extracellular lipase production using ...

    African Journals Online (AJOL)

    The aim of this study was to isolate and select lipase-producing microorganisms originated from different substrates, as well as to optimize the production of microbial lipase by submerged fermentation under different nutrient conditions. Of the 40 microorganisms isolated, 39 showed a halo around the colonies and 4 were ...

  4. optimal selection of hydraulic turbines for small hydro electric power

    African Journals Online (AJOL)

    eobe

    Keywords: optimal selection, SHP turbine, flow duration curve, energy efficiency, annual capacity factor. 1. INTRODUCTION ... depleted, with adverse environmental impacts downstream ..... Technologies, Financing Cogeneration and Small -.

  5. A European survey on donor deferral for allergy

    DEFF Research Database (Denmark)

    Garraud, O; Martin, C; Haddad, A

    2017-01-01

    Allergy accounts to near 0.5% of all reported transfusion adverse events. The responsibility of blood components themselves and - therefore - of blood donors is still questioned. The European Community undertook a large international survey to address the consistency and homogeneity of medical...... selection of blood donors with regard to the risk of allergy, and especially of transferring allergy to recipients. This short report presents the salient points of the survey, stressing that there is inconsistency in addressing the allergy question within countries or systems, with paths of improvement....

  6. Humoral and cellular CMV responses in healthy donors; identification of a frequent population of CMV-specific, CD4+ T cells in seronegative donors

    DEFF Research Database (Denmark)

    Loeth, Nina; Assing, Kristian; Madsen, Hans O

    2012-01-01

    .e., T lymphocyte) assays. Here, we have analyzed the CMV status of 100 healthy blood bank donors using both serology and cellular assays. About half (56%) were found to be CMV seropositive, and they all mounted strong CD8+ and/or moderate CD4+ T cell responses ex vivo against the immunodominant CMV...... protein, pp65. Of the 44 seronegative donors, only five (11%) mounted ex vivo T cell responses; surprisingly, 33 (75%) mounted strong CD4+ T cell responses after a brief in vitro peptide stimulation culture. This may have significant implications for the analysis and selection of HCT donors.......CMV status is an important risk factor in immune compromised patients. In hematopoeitic cell transplantations (HCT), both donor and recipient are tested routinely for CMV status by serological assays; however, one might argue that it might also be of relevance to examine CMV status by cellular (i...

  7. Nucleic acid amplification test for detection of west nile virus infection in pakistani blood donors

    International Nuclear Information System (INIS)

    Niazi, S.K.; Alam, M.

    2017-01-01

    Background: The study was planned to determine the presence of West Nile Virus (WNV) infection in Pakistani blood donors, using Nucleic Acid Amplification Test (NAT). Methods: The blood donors for study were selected on the basis of the standard questionnaire and routine screening results. Six donors were pooled using an automated pipettor and NAT for WNV was performed on Roche Cobas s 201 NAT system. The reactive pools were resolved in Individual Donation-NAT (ID-NAT) format and a sample from FFP bags of reactive donations was retrieved. NAT was again performed on retrieved plasma bag (RPB) sample to confirm the reactive donations. The donors were also recalled and interviewed about history of illness related to recent WNV infection. Results: After serological screening of 1929 donors during the study period, 1860 donors were selected for NAT test for WNV detection. The mean age of the donors was 28±8.77 (range: 18–57 years). 1847 (99.3%) donors were male and 13 (0.7%) were female. NAT for WNV identified six initially reactive pools (0.32%). On follow-up testing with RPB samples, 4 donors (0.21%) were found confirmed reactive for WNV RNA (NAT yield of 1 in 465 blood donors). Conclusion: WNV is a threat to safety of blood products in Pakistan. A screening strategy can be implemented after a large-scale study and financial considerations. One of the reduced cost screening strategies is seasonal screening of blood donors for WNV, with pooling of samples. (author)

  8. Evaluation of diphtheria convalescent patients to serve as donors for the production of anti-diphtheria immunoglobulin preparations

    NARCIS (Netherlands)

    Bissumbhar, B.; Rakhmanova, A.G.; Berbers, G.; Iakolev, A.; Nosikova, E.; Melnick, O.; Ovtcharenko, E.; Rümke, H. C.; Ruitenberg, E.J.

    2004-01-01

    Aims: The study was conducted to evaluate the possibility of selecting convalescent diphtheria patients to serve in emergency situations as donors for the production of anti-diphtheria immunoglobulin. To select suitable donors, the criterion of an antitoxin titer ≥3.0 IU/ml was used. In addition,

  9. Donor, dad, or…? Young adults with lesbian parents' experiences with known donors.

    Science.gov (United States)

    Goldberg, Abbie E; Allen, Katherine R

    2013-06-01

    In this exploratory qualitative study of 11 young adults, ages 19-29 years, we examine how young people who were raised by lesbian parents make meaning out of and construct their relationships with known donors. In-depth interviews were conducted to examine how participants defined their family composition, how they perceived the role of their donors in their lives, and how they negotiated their relationships with their donors. Findings indicate that mothers typically chose known donors who were family friends, that the majority of participants always knew who their donors were, and that their contact with donors ranged from minimal to involved. Further, participants perceived their donors in one of three ways: as strictly donors and not members of their family; as extended family members but not as parents; and as fathers. The more limited role of donors in participants' construction of family relationships sheds light on how children raised in lesbian, gay, and bisexual families are contributing to the redefinition and reconstruction of complex kinship arrangements. Our findings hold implications for clinicians who work with lesbian-mother families, and suggest that young adulthood is an important developmental phase during which interest in and contact with the donor may shift, warranting a transfer of responsibility from mother to offspring in terms of managing the donor-child relationship. © FPI, Inc.

  10. Electroluminescence from charge transfer states in Donor/Acceptor solar cells

    DEFF Research Database (Denmark)

    Sherafatipour, Golenaz; Madsen, Morten

    Charge photocurrent generation is a key process in solar energy conversion systems. Effective dissociation of the photo-generated electron-hole pairs (excitons) has a strong influence on the efficiency of the organic solar cells. Charge dissociation takes place at the donor/acceptor interface via...... which the maximum open-circuit voltage can be estimated, and further can be used in the modeling and optimization of the OPV devices. [1] C. Deibe, T. Strobe, and V. Dyakonov, “Role of the charge transfer state in organic donor-acceptor solar cells,” Adv. Mater., vol. 22, pp. 4097–4111, 2010. [2] K...... charge transfer (CT) excitons, which is Coulombically bound interfacial electron- hole pairs residing at the donor/acceptor heterojunctions. The CT state represents an intermediate state between the exciton dissociation and recombination back to the ground state. Since the recombination of photo...

  11. Recommendations for use of marginal donors in heart transplantation: Brazilian Association of Organs Transplantation guideline.

    Science.gov (United States)

    Fiorelli, A I; Stolf, N A G; Pego-Fernandes, P M; Oliveira Junior, J L; Santos, R H B; Contreras, C A M; Filho, D D L; Dinkhuysen, J J; Moreira, M C V; Mejia, J A C; Castro, M C R

    2011-01-01

    The high prevalence of heart failure has increased the candidate list for heart transplantation; however, there is a shortage of viable donated organs, which is responsible for the high mortality of patients awaiting a transplantation. Because the marginal donor presents additional risk factors, it is not considered to be an ideal donor. The use of a marginal donor is only justified in situations when the risk of patient death due to heart disease is greater than that offered by the donor. These recommendations sought to expand the supply of donors, consequently increasing the transplant rate. We selected articles based on robust evidence to provide a substratum to develop recommendations for donors who exceed the traditional acceptance criteria. Recipient survival in the immediate postoperative period is intimately linked to allograft quality. Primary allograft failure is responsible for 38% to 40% of immediate deaths after heart transplantation: therefore; marginal donor selection must be more rigorous to not increase the surgical risk. The main donor risk factors with the respective evidence levels are: cancer in the donor (B), female donor (B), donor death due to hemorrhagic stroke (B), donor age above 50 years (relative risk [RR] = 1.5) (B), weight mismatch between donor and recipient 240 minutes (RR = 1.2) (B), left ventricular dysfunction with ejection fraction below 45% (B), and use of high doses of vasoactive drugs (dopamine > 15 mg/kg·min) (B). Factors that impact recipient mortality are: age over 50 years (RR = 1.5); allograft harvest at a distance; adult recipient weighing more than 20% of the donor; high doses of vasoactive drugs (dopamine greater than 15 mg/kg·min) and ischemic time >4 hours. The use of a marginal donor is only justified when it is able to increase life expectancy compared with clinical treatment, albeit the outcomes are interior to those using an ideal donor. Copyright © 2011 Elsevier Inc. All rights reserved.

  12. Age-Related Differences in Goals: Testing Predictions from Selection, Optimization, and Compensation Theory and Socioemotional Selectivity Theory

    Science.gov (United States)

    Penningroth, Suzanna L.; Scott, Walter D.

    2012-01-01

    Two prominent theories of lifespan development, socioemotional selectivity theory and selection, optimization, and compensation theory, make similar predictions for differences in the goal representations of younger and older adults. Our purpose was to test whether the goals of younger and older adults differed in ways predicted by these two…

  13. Laparoscopic donor nephrectomy

    Directory of Open Access Journals (Sweden)

    Gupta Nitin

    2005-01-01

    Full Text Available Of the various options for patients with end stage renal disease, kidney transplantation is the treatment of choice for a suitable patient. The kidney for transplantation is retrieved from either a cadaver or a live donor. Living donor nephrectomy has been developed as a method to address the shortfall in cadaveric kidneys available for transplantation. Laparoscopic living donor nephrectomy (LLDN, by reducing postoperative pain, shortening convalescence, and improving the cosmetic outcome of the donor nephrectomy, has shown the potential to increase the number of living kidney donations further by removing some of the disincentives inherent to donation itself. The technique of LLDN has undergone evolution at different transplant centers and many modifications have been done to improve donor safety and recipient outcome. Virtually all donors eligible for an open surgical procedure may also undergo the laparoscopic operation. Various earlier contraindications to LDN, such as right donor kidney, multiple vessels, anomalous vasculature and obesity have been overcome with increasing experience. Laparoscopic live donor nephrectomy can be done transperitoneally or retroperitoneally on either side. The approach is most commonly transperitoneal, which allows adequate working space and easy dissection. A review of literature and our experience with regards to standard approach and the modifications is presented including a cost saving model for the developing countries. An assessment has been made, of the impact of LDN on the outcome of donor and the recipient.

  14. A compensatory approach to optimal selection with mastery scores

    NARCIS (Netherlands)

    van der Linden, Willem J.; Vos, Hendrik J.

    1994-01-01

    This paper presents some Bayesian theories of simultaneous optimization of decision rules for test-based decisions. Simultaneous decision making arises when an institution has to make a series of selection, placement, or mastery decisions with respect to subjects from a population. An obvious

  15. Comparison of Optimal Portfolios Selected by Multicriterial Model Using Absolute and Relative Criteria Values

    Directory of Open Access Journals (Sweden)

    Branka Marasović

    2009-03-01

    Full Text Available In this paper we select an optimal portfolio on the Croatian capital market by using the multicriterial programming. In accordance with the modern portfolio theory maximisation of returns at minimal risk should be the investment goal of any successful investor. However, contrary to the expectations of the modern portfolio theory, the tests carried out on a number of financial markets reveal the existence of other indicators important in portfolio selection. Considering the importance of variables other than return and risk, selection of the optimal portfolio becomes a multicriterial problem which should be solved by using the appropriate techniques.In order to select an optimal portfolio, absolute values of criteria, like return, risk, price to earning value ratio (P/E, price to book value ratio (P/B and price to sale value ratio (P/S are included in our multicriterial model. However the problem might occur as the mean values of some criteria are significantly different for different sectors and because financial managers emphasize that comparison of the same criteria for different sectors could lead us to wrong conclusions. In the second part of the paper, relative values of previously stated criteria (in relation to mean value of sector are included in model for selecting optimal portfolio. Furthermore, the paper shows that if relative values of criteria are included in multicriterial model for selecting optimal portfolio, return in subsequent period is considerably higher than if absolute values of the same criteria were used.

  16. Risk factors for human immunodeficiency virus among blood donors in Cameroon: evidence for the design of an Africa-specific donor history questionnaire.

    Science.gov (United States)

    Tagny, Claude T; Nguefack-Tsague, Georges; Fopa, Diderot; Ashu, Celestin; Tante, Estel; Ngo Balogog, Pauline; Donfack, Olivier; Mbanya, Dora; Laperche, Syria; Murphy, Edward

    2017-08-01

    In sub-Saharan Africa improving the deferral of at-risk blood donors would be a cost-effective approach to reducing transfusion-transmitted human immunodeficiency virus (HIV) infections. We performed a pilot case-control study to identify the risk factors for HIV infection and to develop an adapted donor history questionnaire (DHQ) for sub-Saharan Africa. We recruited 137 HIV-positive donors (cases) and 256 HIV-negative donors (controls) and gathered risk factor data using audio computer-assisted self-interview. Variables with univariate associations were entered into a logistic regression model to assess independent associations. A scoring scheme to distinguish between HIV-positive and HIV-negative donors was developed using receiver operating characteristics curves. We identified 16 risk factors including sex with sex worker, past history or treatment for sexually transmitted infections, and having a partner who used injected or noninjected illegal drugs. Two novel risks were related to local behavior: polygamy (odds ratio [OR], 22.7; 95% confidence interval [CI], 5.9-86.7) and medical or grooming treatment on the street (OR, 1.8; 95% CI, 1.0-3.0). Using the 16 selected items the mean scores (>100) were 82.6 ± 6.7 (range, 53.2-95.1) and 85.1 ± 5.2 for HIV-negative donors versus 77.9 ± 6.8 for HIV-positive ones (p = 0.000). Donors who scored between 80 and 90 were more likely to be HIV negative than those who scored less (OR, 31.4; 95% CI, 3.1-313.9). We identified both typical and novel HIV risk factors among Cameroonian blood donors. An adapted DHQ and score that discriminate HIV-negative donors may be an inexpensive means of reducing transfusion-transmitted HIV through predonation screening. © 2017 AABB.

  17. Benzo[1,2-b:4,5-b′]Dithiophene-6,7-Difluoroquinoxaline Small Molecule Donors with >8% BHJ Solar Cell Efficiency

    KAUST Repository

    Liang, Ru-Ze

    2017-07-14

    Solution-processable small molecule (SM) donors are promising alternatives to their polymer counterparts in bulk-heterojunction (BHJ) solar cells. While SM donors with favorable spectral absorption, self-assembly patterns, optimum thin-film morphologies, and high carrier mobilities in optimized donor–acceptor blends are required to further BHJ device efficiencies, material structure governs each one of those attributes. As a result, the rational design of SM donors with gradually improved BHJ solar cell efficiencies must concurrently address: (i) bandgap tuning and optimization of spectral absorption (inherent to the SM main chain) and (ii) pendant-group substitution promoting structural order and mediating morphological effects. In this paper, the rational pendant-group substitution in benzo[1,2-b:4,5-b′]dithiophene–6,7-difluoroquinoxaline SMs is shown to be an effective approach to narrowing the optical gap (Eopt) of the SM donors (SM1 and SM2), without altering their propensity to order and form favorable thin-film BHJ morphologies with PC71BM. Systematic device examinations show that power conversion efficiencies >8% and open-circuit voltages (VOC) nearing 1 V can be achieved with the narrow-gap SM donor analog (SM2, Eopt = 1.6 eV) and that charge transport in optimized BHJ solar cells proceeds with minimal, nearly trap-free recombination. Detailed device simulations, light intensity dependence, and transient photocurrent analyses emphasize how carrier recombination impacts BHJ device performance upon optimization of active layer thickness and morphology.

  18. Serum neopterin: a potential marker for screening blood donors

    International Nuclear Information System (INIS)

    Ashfaq, A.; Ejaz, A.; Abbas, G.

    2017-01-01

    To determine serum neopterin levels in blood donors of local population and its association with transfusion ransmitted infections. Study Design: A cross-sectional observational study. Place and Duration of Study:Department of Physiology, Liaquat National Hospital and Medical College (LNHMC) in collaboration with Basic Medical Sciences Institute (BMSI) and Jinnah Postgraduate Medical Centre (JPMC), Blood Bank, Karachi, Pakistan, from January to June 2015. Methodology: During this period, a total of 174 blood donors were selected through random sampling technique. All participants fulfilling the inclusion criteria involving apparently healthy blood donors of either gender within the age bracket of 18 - 60 years and consenting to participate were selected. The participants were screened for transfusion transmitted infections as per WHO recommendations through the standard procedures used for screening at the JPMC blood bank. The demographic profile, anthropometric measurements and vitals were recorded for every participant. Serum neopterin was measured using ELISA kits. Data was analysed on SPSS version 21. ANOVA and chi-square tests were applied as tests of significance at a p-value of <0.05. Results: The neopterin content in the sera of disease negative blood donors was 6.23 +-2.19 nmol/l as compared to disease positive blood donors, in whom the neopterin level was increased to 15.10 +-4.93 nmol/l (p =0.001). Conclusion: The neopterin assay has the potential to detect a number of transfusion transmissible viral diseases; which may, or may not be revealed by the usually employed battery of routine tests. We conclude that the risk of transfusion transmitted pathogens in our population can be reduced significantly, using neopterin assay as a routine in blood banks. (author)

  19. DISAL glycosyl donors for the synthesis of a linear hexasaccharide under mild conditions

    DEFF Research Database (Denmark)

    Petersen, Lars; Laursen, Jane B.; Larsen, K.

    2003-01-01

    The new class of glycosyl donors with a methyl 3,5-dinitrosalicylate (DISAL) anomeric leaving group has proved efficient for glycosylation under strictly neutral, mildly basic, or mildly acidic conditions. Here, we report the synthesis of novel DISAL disaccharide glycosyl donors prepared by easy...... nucleophilic aromatic substitution. These DISAL donors proved efficient in the synthesis of a starch-related hexasaccharide under very mild conditions. Glycosylations proceeded with alpha-selectivity and were compatible with Trt protecting groups....

  20. Donor Hemovigilance Programme in managing Blood Transfusion Needs: Complications of Whole Blood Donation

    OpenAIRE

    S Mangwana

    2013-01-01

    Background: Hemovigilance like quality systems and audits have become an integral part of Blood Transfusion Services in the developed countries and has contributed greatly to its development. Hemovigilance begins with donors and must enable the collection of information on reactions occurring during the donation of blood, selections of donors and to prevent such incidents. The aim of study was to help identify the trends of adverse events , occurring in blood donors at a tertiary-care hospita...

  1. An Improved Test Selection Optimization Model Based on Fault Ambiguity Group Isolation and Chaotic Discrete PSO

    Directory of Open Access Journals (Sweden)

    Xiaofeng Lv

    2018-01-01

    Full Text Available Sensor data-based test selection optimization is the basis for designing a test work, which ensures that the system is tested under the constraint of the conventional indexes such as fault detection rate (FDR and fault isolation rate (FIR. From the perspective of equipment maintenance support, the ambiguity isolation has a significant effect on the result of test selection. In this paper, an improved test selection optimization model is proposed by considering the ambiguity degree of fault isolation. In the new model, the fault test dependency matrix is adopted to model the correlation between the system fault and the test group. The objective function of the proposed model is minimizing the test cost with the constraint of FDR and FIR. The improved chaotic discrete particle swarm optimization (PSO algorithm is adopted to solve the improved test selection optimization model. The new test selection optimization model is more consistent with real complicated engineering systems. The experimental result verifies the effectiveness of the proposed method.

  2. Dual kidney transplants from adult marginal donors successfully expand the limited deceased donor organ pool.

    Science.gov (United States)

    Stratta, Robert J; Farney, Alan C; Orlando, Giuseppe; Farooq, Umar; Al-Shraideh, Yousef; Palanisamy, Amudha; Reeves-Daniel, Amber; Doares, William; Kaczmorski, Scott; Gautreaux, Michael D; Iskandar, Samy S; Hairston, Gloria; Brim, Elizabeth; Mangus, Margaret; El-Hennawy, Hany; Khan, Muhammad; Rogers, Jeffrey

    2016-04-01

    The need to expand the organ donor pool remains a formidable challenge in kidney transplantation (KT). The use of expanded criteria donors (ECDs) represents one approach, but kidney discard rates are high because of concerns regarding overall quality. Dual KT (DKT) may reduce organ discard and optimize the use of kidneys from marginal donors. We conducted a single-center retrospective review of outcomes in adult recipients of DKTs from adult marginal deceased donors (DD) defined by limited renal functional capacity. If the calculated creatinine clearance in an adult DD was DKT. Over 11.5 yr, 72 DKTS were performed including 45 from ECDs, 17 from donation after cardiac death (DCD) donors, and 10 from standard criteria donors (SCD). Mean adult DD and recipient ages were both 60 yr, including 29 DDs and 26 recipients ≥65 yr of age. Mean pre-DKT waiting and dialysis vintage times were 12 months and 25 months, respectively. Actual patient and graft survival rates were 84.7% and 70.8%, respectively, with a mean follow-up of 58 months. One yr and death-censored graft survival rates were 90% and 80%, respectively. Outcomes did not differ by DD category, recipient age, or presence of delayed graft function (DGF). Eleven patients died at a mean of 32 months post-DKT (eight with functioning grafts) and 13 other patients experienced graft losses at a mean of 33 months. The incidence of DGF was 25%; there were two cases (2.8%) of primary non-function. Mean length of initial hospital stay was 7.2 d. Mean serum creatinine and glomerular filtration rate levels at 12 and 24 months were 1.5 and 53 and 1.5 mg/dL and 51 mL/min/1.73 m(2) , respectively. DKT graft survival and function were superior to concurrent single ECD and similar to concurrent SCD KTs. Two patients underwent successful kidney retransplantation, so the dialysis-free rate in surviving patients was 87%. The proportion of total renal function transplanted from adult DD to DKT recipients was 77% compared to 56% for

  3. Complexation of trivalent cationic lanthanides by N.O donor ligands: physico-chemical studies of the association and selectivity in solution

    International Nuclear Information System (INIS)

    Bravard, F.

    2004-01-01

    The aim of this work is to study the complexation of f-elements in solution by ligands incorporating N-heterocyclic donors. These ligands display interesting properties for the selective separation of An(III)/Ln(III) have been studied to obtain a better understanding of the coordination properties with f-elements and to develop more selective extractants. The hepta-dentate ligand tpaam shows an affinity for Ln(III) similar to the tetradentate ligand tpa in water even when the three additional amide groups are bonded to the metal. Even though the complexation with tpa is exothermic, that with tpaam is endothermic with a more positive entropy. The dehydration of the cation disfavours the formation of Ln(III) complexes with ligands containing weak donors. The analysis of the solution paramagnetic relaxation times of the tpaam complexes is in agreement with data in the solid-state. There is little difference between the formation constants of the Ln 3+ complexes with different ligands (tpaam, tpzen, tpa and tpza) as determined by UV-vis spectrophotometry in anhydrous acetonitrile. The limitations encountered during this study are intrinsic to the ligands studied. The preliminary study of two tetrapodal ligands containing acid and pyridine groups (L py )or pyrazine (L pz ) show the formation of 1:1 complexes in water. Analysis of the formation constants of the corresponding Gd(III) complexes shows that replacement of a pyridine group by pyrazine result in a loss of stability of 1.6 logarithmic units. (author) [fr

  4. Marginal kidney donor

    Directory of Open Access Journals (Sweden)

    Ganesh Gopalakrishnan

    2007-01-01

    Full Text Available Renal transplantation is the treatment of choice for a medically eligible patient with end stage renal disease. The number of renal transplants has increased rapidly over the last two decades. However, the demand for organs has increased even more. This disparity between the availability of organs and waitlisted patients for transplants has forced many transplant centers across the world to use marginal kidneys and donors. We performed a Medline search to establish the current status of marginal kidney donors in the world. Transplant programs using marginal deceased renal grafts is well established. The focus is now on efforts to improve their results. Utilization of non-heart-beating donors is still in a plateau phase and comprises a minor percentage of deceased donations. The main concern is primary non-function of the renal graft apart from legal and ethical issues. Transplants with living donors outnumbered cadaveric transplants at many centers in the last decade. There has been an increased use of marginal living kidney donors with some acceptable medical risks. Our primary concern is the safety of the living donor. There is not enough scientific data available to quantify the risks involved for such donation. The definition of marginal living donor is still not clear and there are no uniform recommendations. The decision must be tailored to each donor who in turn should be actively involved at all levels of the decision-making process. In the current circumstances, our responsibility is very crucial in making decisions for either accepting or rejecting a marginal living donor.

  5. LAPAROSCOPIC LEFT LATERAL SECTIONECTOMY IN LIVING LIVER DONOR

    Directory of Open Access Journals (Sweden)

    S. V. Gautier

    2016-01-01

    Full Text Available Introduction. Living donor liver transplantation has proved to be an effective, safe and radical treatment modality for patients with end-stage liver diseases. Left lateral section (LLS of donor’s liver is used in pediatric recipients. Laparoscopic LLS procurement was fi rst described by D. Cherqui in 2002. At present, this technique is routinely used only by 5 hospitals in the world. However, up to date, some authors consider it to be a new standard to perform such a surgery in living donors.Aim. To analyze the fi rst Russian experience in laparoscopic left lateral sectionectomy (LapLLS in living related donor.Materials and methods. From May to September 2016 fi ve LapLLS were performed in living donors. In all cases donors were women (mothers in 4 cases and aunt in 1 case. Recipients were children aged from 6 months through 3 years with body mass from 5.6 to 12.5 kg. Liver transection was carried out under conditions of maintained blood supply. Parenchymal transection was performed using a harmonic scalpel, bipolar coagulation and ultrasound dissection.Results. Average donor age was 32 ± 5 years. Average operation time was 287 ± 16 min. Average LLS graft weight was 220 ± 16 g. Intraoperative blood loss did not exceed 100 ml (95 ± 5 ml. Donors were discharged on the 3rd–4th post-op day. There were no postoperative complications in donors. Recipients were also characterized by a standard course of the postoperative period.Conclusion. LapLLS is an effective and safe method with several advantages. Primarily, these are early rehabilitation of the donors and shortening of the hospital stay, which are important for the quick return to normal way of live. Excellent visualization of anatomical structures, including vascular and biliary ones, allows performing precise selection. In addition, good cosmetic effect is also an important aspect.

  6. Long-term Outcomes for Living Pancreas Donors in the Modern Era.

    Science.gov (United States)

    Kirchner, Varvara A; Finger, Erik B; Bellin, Melena D; Dunn, Ty B; Gruessner, Rainer W G; Hering, Bernhard J; Humar, Abhinav; Kukla, Aleksandra K; Matas, Arthur J; Pruett, Timothy L; Sutherland, David E R; Kandaswamy, Raja

    2016-06-01

    Living donor segmental pancreas transplants (LDSPTx) have been performed selectively to offer a preemptive transplant option for simultaneous pancreas-kidney recipients and to perform a single operation decreasing the cost of pancreas after kidney transplant. For solitary pancreas transplants, this option historically provided a better immunologic match. Although short-term donor outcomes have been documented, there are no long-term studies. We studied postdonation outcomes in 46 segmental pancreas living donors. Surgical complications, risk factors (RF) for development of diabetes mellitus (DM) and quality of life were studied. A risk stratification model (RSM) for DM was created using predonation and postdonation RFs. Recipient outcomes were analyzed. Between January 1, 1994 and May 1, 2013, 46 LDSPTx were performed. Intraoperatively, 5 (11%) donors received transfusion. Overall, 9 (20%) donors underwent splenectomy. Postoperative complications included: 6 (13%) peripancreatic fluid collections and 2 (4%) pancreatitis episodes. Postdonation, DM requiring oral hypoglycemics was diagnosed in 7 (15%) donors and insulin-dependent DM in 5 (11%) donors. RSM with three predonation RFs (oral glucose tolerance test, basal insulin, fasting plasma glucose) and 1 postdonation RF, greater than 15% increase in body mass index from preoperative (Δ body mass index >15), predicted 12 (100%) donors that developed postdonation DM. Quality of life was not significantly affected by donation. Mean graft survival was 9.5 (±4.4) years from donors without and 9.6 (±5.4) years from donors with postdonation DM. LDSPTx can be performed with good recipient outcomes. The donation is associated with donor morbidity including impaired glucose control. Donor morbidity can be minimized by using RSM and predonation counseling on life style modifications postdonation.

  7. Donor Retention in Online Crowdfunding Communities: A Case Study of DonorsChoose.org.

    Science.gov (United States)

    Althoff, Tim; Leskovec, Jure

    2015-05-01

    Online crowdfunding platforms like DonorsChoose.org and Kick-starter allow specific projects to get funded by targeted contributions from a large number of people. Critical for the success of crowdfunding communities is recruitment and continued engagement of donors. With donor attrition rates above 70%, a significant challenge for online crowdfunding platforms as well as traditional offline non-profit organizations is the problem of donor retention. We present a large-scale study of millions of donors and donations on DonorsChoose.org, a crowdfunding platform for education projects. Studying an online crowdfunding platform allows for an unprecedented detailed view of how people direct their donations. We explore various factors impacting donor retention which allows us to identify different groups of donors and quantify their propensity to return for subsequent donations. We find that donors are more likely to return if they had a positive interaction with the receiver of the donation. We also show that this includes appropriate and timely recognition of their support as well as detailed communication of their impact. Finally, we discuss how our findings could inform steps to improve donor retention in crowdfunding communities and non-profit organizations.

  8. Early declaration of death by neurologic criteria results in greater organ donor potential.

    Science.gov (United States)

    Resnick, Shelby; Seamon, Mark J; Holena, Daniel; Pascual, Jose; Reilly, Patrick M; Martin, Niels D

    2017-10-01

    Aggressive management of patients prior to and after determination of death by neurologic criteria (DNC) is necessary to optimize organ recovery, transplantation, and increase the number of organs transplanted per donor (OTPD). The effects of time management are understudied but potentially pivotal component. The objective of this study was to analyze specific time points (time to DNC, time to procurement) and the time intervals between them to better characterize the optimal timeline of organ donation. Using data over a 5-year time period (2011-2015) from the largest US OPO, all patients with catastrophic brain injury and donated transplantable organs were retrospectively reviewed. Active smokers were excluded. Maximum donor potential was seven organs (heart, lungs [2], kidneys [2], liver, and pancreas). Time from admission to declaration of DNC and donation was calculated. Mean time points stratified by specific organ procurement rates and overall OTPD were compared using unpaired t-test. Of 1719 Declaration of Death by Neurologic Criteria organ donors, 381 were secondary to head trauma. Smokers and organs recovered but not transplanted were excluded leaving 297 patients. Males comprised 78.8%, the mean age was 36.0 (±16.8) years, and 87.6% were treated at a trauma center. Higher donor potential (>4 OTPD) was associated with shorter average times from admission to brain death; 66.6 versus 82.2 hours, P = 0.04. Lung donors were also associated with shorter average times from admission to brain death; 61.6 versus 83.6 hours, P = 0.004. The time interval from DNC to donation varied minimally among groups and did not affect donation rates. A shorter time interval between admission and declaration of DNC was associated with increased OTPD, especially lungs. Further research to identify what role timing plays in the management of the potential organ donor and how that relates to donor management goals is needed. Copyright © 2017 Elsevier Inc. All rights

  9. Robotic-assisted single-port donor nephrectomy using the da Vinci single-site platform.

    Science.gov (United States)

    LaMattina, John C; Alvarez-Casas, Josue; Lu, Irene; Powell, Jessica M; Sultan, Samuel; Phelan, Michael W; Barth, Rolf N

    2018-02-01

    Although single-port donor nephrectomy offers improved cosmetic outcomes, technical challenges have limited its application to selected centers. Our center has performed over 400 single-port donor nephrectomies. The da Vinci single-site robotic platform was utilized in an effort to overcome the steric, visualization, ergonomic, and other technical limitations associated with the single-port approach. Food and Drug Administration device exemption was obtained. Selection criteria for kidney donation included body mass index da Vinci single-site platform. Our experience supported the safety of this approach but found that the technology added cost and complexity without tangible benefit. Development of articulating instruments, energy, and stapling devices will be necessary for increased application of robotic single-site surgery for donor nephrectomy. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Design optimization and analysis of selected thermal devices using self-adaptive Jaya algorithm

    International Nuclear Information System (INIS)

    Rao, R.V.; More, K.C.

    2017-01-01

    Highlights: • Self-adaptive Jaya algorithm is proposed for optimal design of thermal devices. • Optimization of heat pipe, cooling tower, heat sink and thermo-acoustic prime mover is presented. • Results of the proposed algorithm are better than the other optimization techniques. • The proposed algorithm may be conveniently used for the optimization of other devices. - Abstract: The present study explores the use of an improved Jaya algorithm called self-adaptive Jaya algorithm for optimal design of selected thermal devices viz; heat pipe, cooling tower, honeycomb heat sink and thermo-acoustic prime mover. Four different optimization case studies of the selected thermal devices are presented. The researchers had attempted the same design problems in the past using niched pareto genetic algorithm (NPGA), response surface method (RSM), leap-frog optimization program with constraints (LFOPC) algorithm, teaching-learning based optimization (TLBO) algorithm, grenade explosion method (GEM) and multi-objective genetic algorithm (MOGA). The results achieved by using self-adaptive Jaya algorithm are compared with those achieved by using the NPGA, RSM, LFOPC, TLBO, GEM and MOGA algorithms. The self-adaptive Jaya algorithm is proved superior as compared to the other optimization methods in terms of the results, computational effort and function evalutions.

  11. Optimal Portfolio Selection Under Concave Price Impact

    International Nuclear Information System (INIS)

    Ma Jin; Song Qingshuo; Xu Jing; Zhang Jianfeng

    2013-01-01

    In this paper we study an optimal portfolio selection problem under instantaneous price impact. Based on some empirical analysis in the literature, we model such impact as a concave function of the trading size when the trading size is small. The price impact can be thought of as either a liquidity cost or a transaction cost, but the concavity nature of the cost leads to some fundamental difference from those in the existing literature. We show that the problem can be reduced to an impulse control problem, but without fixed cost, and that the value function is a viscosity solution to a special type of Quasi-Variational Inequality (QVI). We also prove directly (without using the solution to the QVI) that the optimal strategy exists and more importantly, despite the absence of a fixed cost, it is still in a “piecewise constant” form, reflecting a more practical perspective.

  12. Optimal Portfolio Selection Under Concave Price Impact

    Energy Technology Data Exchange (ETDEWEB)

    Ma Jin, E-mail: jinma@usc.edu [University of Southern California, Department of Mathematics (United States); Song Qingshuo, E-mail: songe.qingshuo@cityu.edu.hk [City University of Hong Kong, Department of Mathematics (Hong Kong); Xu Jing, E-mail: xujing8023@yahoo.com.cn [Chongqing University, School of Economics and Business Administration (China); Zhang Jianfeng, E-mail: jianfenz@usc.edu [University of Southern California, Department of Mathematics (United States)

    2013-06-15

    In this paper we study an optimal portfolio selection problem under instantaneous price impact. Based on some empirical analysis in the literature, we model such impact as a concave function of the trading size when the trading size is small. The price impact can be thought of as either a liquidity cost or a transaction cost, but the concavity nature of the cost leads to some fundamental difference from those in the existing literature. We show that the problem can be reduced to an impulse control problem, but without fixed cost, and that the value function is a viscosity solution to a special type of Quasi-Variational Inequality (QVI). We also prove directly (without using the solution to the QVI) that the optimal strategy exists and more importantly, despite the absence of a fixed cost, it is still in a 'piecewise constant' form, reflecting a more practical perspective.

  13. Nyretransplantation med levende donor

    DEFF Research Database (Denmark)

    Kamper, A L; Løkkegaard, H; Rasmussen, F

    2000-01-01

    In recent years transplantation from living donors has accounted for 25-30% of all kidney transplants in Denmark corresponding to 40-45 per year. Most of these living donors are parents or siblings, although internationally an increasing number are unrelated donors. Donor nephrectomy is associate...... in cadaver transplantation. The ethical and psychological aspects related to transplantation from a living donor are complex and need to be carefully evaluated when this treatment is offered to the patients....

  14. Having a sibling as donor: patients' experiences immediately before allogeneic hematopoietic stem cell transplantation.

    Science.gov (United States)

    Kisch, Annika; Bolmsjö, Ingrid; Lenhoff, Stig; Bengtsson, Mariette

    2014-08-01

    Allogeneic hematopoietic stem cell transplantation (HSCT) offers a potential cure for a variety of diseases but is also associated with significant risks. With HSCT the donor is either a relative, most often a sibling, or an unrelated registry donor. The aim was to explore patients' experiences, immediately before transplantation, regarding having a sibling as donor. Ten adult patients with sibling donors were interviewed before admission for HSCT. The interviews were digitally recorded, transcribed verbatim and subjected to qualitative content analysis. The main theme Being in no man's land is a metaphor for the patients' complex situation with its mixture of emotions and thoughts prior to transplantation. The three subthemes Trust in the sibling donor, Concern about others and Loss of control cover the various experiences. The patient's experiences are influenced by their personal situation and the quality of the relationship with the sibling donor. While patients feel secure in having a sibling donor, they are dependent for their survival on the cell donation and feel responsible for the donor's safety during donation. These emotions intensify the patients' sense of dependency and loss of control. In caring for HSCT patients the nurses should be aware of the complexity of the patients' situation and keep in mind that having a sibling donor might imply extra pressure, including a sense of responsibility. Caring for both patients and sibling donors optimally is a challenge, which needs further improvement and exploration. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. ORIGINAL ARTICLE: Blood Donor’s Status of HIV, HBV, HCV and Syphilis in this Region of Marathwada, India

    Directory of Open Access Journals (Sweden)

    Rangrao H. Deshpande

    2012-07-01

    Full Text Available Aims & Objectives: Blood transfusion can cause the transmission of infections to recipients. This is an important mode of infection. The aim of study was to assess the prevalence of such type of infections among blood donors and to compare the seroprevalence of transfusion transmitted diseases in voluntary donors and replacement donors. Retrospective study of five years from Jan. 2007 to Dec. 2011 was done. This study was conducted at Blood bank, MIMSR Medical College Latur, Govt. Medical College, Latur and Bhalchandra Blood bank, Latur. Material & Methods: Total 10, 4925 donors were tested. Donors were screened for seroprevalence of HIV, HBC, HCV and Syphilis. Screening of HIV, HBV & HCV was done by ELISA method & Syphilis was screened by RPR type. Results: The comparison of seroprevalence of HIV, HBV, HCV & Syphilis in voluntary donors and replacement donors showed significant difference only for HIV in the years 2007, 2010, and 2011. Conclusion: The seroprevalence of transfusion transmitted diseases in the study is very low or negligible in voluntary donors as compared to replacement donors. There was a declining trend of seroprevalence for all the disease screened. But in our study the difference is not significant, which indicates that the selection of donors is of low quality. The selection of high quality voluntary donors should be achieved by creation of awareness by education of the prospective donor populations.

  16. A metaheuristic optimization framework for informative gene selection

    Directory of Open Access Journals (Sweden)

    Kaberi Das

    Full Text Available This paper presents a metaheuristic framework using Harmony Search (HS with Genetic Algorithm (GA for gene selection. The internal architecture of the proposed model broadly works in two phases, in the first phase, the model allows the hybridization of HS with GA to compute and evaluate the fitness of the randomly selected solutions of binary strings and then HS ranks the solutions in descending order of their fitness. In the second phase, the offsprings are generated using crossover and mutation operations of GA and finally, those offsprings were selected for the next generation whose fitness value is more than their parents evaluated by SVM classifier. The accuracy of the final gene subsets obtained from this model has been evaluated using SVM classifiers. The merit of this approach is analyzed by experimental results on five benchmark datasets and the results showed an impressive accuracy over existing feature selection approaches. The occurrence of gene subsets selected from this model have also been computed and the most often selected gene subsets with the probability of [0.1–0.9] have been chosen as optimal sets of informative genes. Finally, the performance of those selected informative gene subsets have been measured and established through probabilistic measures. Keywords: Gene Selection, Metaheuristic, Harmony Search Algorithm, Genetic Algorithm, SVM

  17. Ways to improve the use of donor resources in the Nizhny Novgorod Region

    Directory of Open Access Journals (Sweden)

    S. V. Romanov

    2018-01-01

    Full Text Available The article analyzes the system of organ transplantation in the Nizhny Novgorod Region in order to determine the ways to optimize the use of donor resource. The authors found that the most difficult are the program activities, the success of which depends on the attitude of health care employees and the population of the region. In this regard, a questionnaire survey was conducted; its results indicated a lack of awareness among doctors and the public about the transplantation role in modern medicine and the legislation in this sphere of relations. The authors come to the conclusion on the importance of the outreach and promotion of the posthumous organ donation program among health care employees and all population groups to optimize the use of donor resource of the region. 

  18. Pipe degradation investigations for optimization of flow-accelerated corrosion inspection location selection

    International Nuclear Information System (INIS)

    Chandra, S.; Habicht, P.; Chexal, B.; Mahini, R.; McBrine, W.; Esselman, T.; Horowitz, J.

    1995-01-01

    A large amount of piping in a typical nuclear power plant is susceptible to Flow-Accelerated Corrosion (FAC) wall thinning to varying degrees. A typical PAC monitoring program includes the wall thickness measurement of a select number of components in order to judge the structural integrity of entire systems. In order to appropriately allocate resources and maintain an adequate FAC program, it is necessary to optimize the selection of components for inspection by focusing on those components which provide the best indication of system susceptibility to FAC. A better understanding of system FAC predictability and the types of FAC damage encountered can provide some of the insight needed to better focus and optimize the inspection plan for an upcoming refueling outage. Laboratory examination of FAC damaged components removed from service at Northeast Utilities' (NU) nuclear power plants provides a better understanding of the damage mechanisms involved and contributing causes. Selected results of this ongoing study are presented with specific conclusions which will help NU to better focus inspections and thus optimize the ongoing FAC inspection program

  19. Optimization of breast reconstruction results using TMG flap in 30 cases: Evaluation of several refinements addressing flap design, shaping techniques, and reduction of donor site morbidity.

    Science.gov (United States)

    Nickl, Stefanie; Nedomansky, Jakob; Radtke, Christine; Haslik, Werner; Schroegendorfer, Klaus F

    2018-01-31

    The transverse myocutaneous gracilis (TMG) flap is a widely used alternative to abdominal flaps in autologous breast reconstruction. However, secondary procedures for aesthetic refinement are frequently necessary. Herein, we present our experience with an optimized approach in TMG breast reconstruction to enhance aesthetic outcome and to reduce the need for secondary refinements. We retrospectively analyzed 37 immediate or delayed reconstructions with TMG flaps in 34 women, performed between 2009 and 2015. Four patients (5 flaps) constituted the conventional group (non-optimized approach). Thirty patients (32 flaps; modified group) underwent an optimized procedure consisting of modified flap harvesting and shaping techniques and methods utilized to reduce denting after rib resection and to diminish donor site morbidity. Statistically significant fewer secondary procedures (0.6 ± 0.9 versus 4.8 ± 2.2; P < .001) and fewer trips to the OR (0.4 ± 0.7 versus 2.3 ± 1.0 times; P = .001) for aesthetic refinement were needed in the modified group as compared to the conventional group. In the modified group, 4 patients (13.3%) required refinement of the reconstructed breast, 7 patients (23.3%) underwent mastopexy/mammoplasty or lipofilling of the contralateral breast, and 4 patients (13.3%) required refinement of the contralateral thigh. Total flap loss did not occur in any patient. Revision surgery was needed once. Compared to the conventional group, enhanced aesthetic results with consecutive reduction of secondary refinements could be achieved when using our modified flap harvesting and shaping techniques, as well as our methods for reducing contour deformities after rib resection and for overcoming donor site morbidities. © 2017 Wiley Periodicals, Inc.

  20. Selection of magnetorheological brake types via optimal design considering maximum torque and constrained volume

    International Nuclear Information System (INIS)

    Nguyen, Q H; Choi, S B

    2012-01-01

    This research focuses on optimal design of different types of magnetorheological brakes (MRBs), from which an optimal selection of MRB types is identified. In the optimization, common types of MRB such as disc-type, drum-type, hybrid-types, and T-shaped type are considered. The optimization problem is to find the optimal value of significant geometric dimensions of the MRB that can produce a maximum braking torque. The MRB is constrained in a cylindrical volume of a specific radius and length. After a brief description of the configuration of MRB types, the braking torques of the MRBs are derived based on the Herschel–Bulkley model of the MR fluid. The optimal design of MRBs constrained in a specific cylindrical volume is then analysed. The objective of the optimization is to maximize the braking torque while the torque ratio (the ratio of maximum braking torque and the zero-field friction torque) is constrained to be greater than a certain value. A finite element analysis integrated with an optimization tool is employed to obtain optimal solutions of the MRBs. Optimal solutions of MRBs constrained in different volumes are obtained based on the proposed optimization procedure. From the results, discussions on the optimal selection of MRB types depending on constrained volumes are given. (paper)

  1. The stock selection problem: Is the stock selection approach more important than the optimization method? Evidence from the Danish stock market

    OpenAIRE

    Grobys, Klaus

    2011-01-01

    Passive investment strategies basically aim to replicate an underlying benchmark. Thereby, the management usually selects a subset of stocks being employed in the optimization procedure. Apart from the optimization procedure, the stock selection approach determines the stock portfolios' out-of-sample performance. The empirical study here takes into account the Danish stock market from 2000-2010 and gives evidence that stock portfolios including small companies' stocks being estimated via coin...

  2. Influence of kinship on donors' mental burden in living donor liver transplantation.

    Science.gov (United States)

    Erim, Yesim; Beckmann, Mingo; Kroencke, Sylvia; Sotiropoulos, Georgios C; Paul, Andreas; Senf, Wolfgang; Schulz, Karl-Heinz

    2012-08-01

    In the context of living donor liver transplantation (LDLT), German transplantation law stipulates that donor candidates should primarily be relatives of the recipients or persons with distinct and close relationships. In this study, we investigated the influence of the relationship between the donor and the recipient on the donor's emotional strain before transplantation. Donors were categorized according to the following subgroups: (1) parents donating for their children, (2) children donating for their parents, (3) siblings, (4) spouses, (5) other relatives, and (6) nonrelatives. The sample consisted of 168 donor candidates. Anxiety (F = 2.8, P = 0.02), depression (F = 2.6, P = 0.03), and emotional quality of life (F = 3.1, P = 0.01) differed significantly according to the relationship between the donor and the recipient. In comparison with healthy controls, parents donating for their children were significantly less stressed before LDLT and demonstrated fewer anxiety (P depression symptoms (P < 0.05). Adult children donating for their parents demonstrated the highest mental burden and the lowest emotional quality of life. However, this was not due to the responsibility of these children for their own families because differences between donors with children and donors without children could not be ascertained. This group should be given special attention before LDLT and during follow-up visits, and psychological help should be provided when it is necessary. Copyright © 2012 American Association for the Study of Liver Diseases.

  3. Iron deficiency in blood donors

    Directory of Open Access Journals (Sweden)

    Rodolfo Delfini Cançado

    Full Text Available CONTEXT: Blood donation results in a substantial loss of iron (200 to 250 mg at each bleeding procedure (425 to 475 ml and subsequent mobilization of iron from body stores. Recent reports have shown that body iron reserves generally are small and iron depletion is more frequent in blood donors than in non-donors. OBJECTIVE: The aim of this study was to evaluate the frequency of iron deficiency in blood donors and to establish the frequency of iron deficiency in blood donors according to sex, whether they were first-time or multi-time donors, and the frequency of donations per year. DESIGN: From September 20 to October 5, 1999, three hundred blood donors from Santa Casa Hemocenter of São Paulo were studied. DIAGNOSTIC TESTS: Using a combination of biochemical measurements of iron status: serum iron, total iron-binding capacity, transferrin saturation index, serum ferritin and the erythrocyte indices. RESULTS: The frequency of iron deficiency in blood donors was 11.0%, of whom 5.5% (13/237 were male and 31.7% (20/63 female donors. The frequency of iron deficiency was higher in multi-time blood donors than in first-time blood donors, for male blood donors (7.6% versus 0.0%, P < 0.05 and female ones (41.5% versus 18.5%, P < 0.05. The frequency of iron deficiency found was higher among the male blood donors with three or more donations per year (P < 0.05 and among the female blood donors with two or more donations per year (P < 0.05. CONCLUSIONS: We conclude that blood donation is a very important factor for iron deficiency in blood donors, particularly in multi-time donors and especially in female donors. The high frequency of blood donors with iron deficiency found in this study suggests a need for a more accurate laboratory trial, as hemoglobin or hematocrit measurement alone is not sufficient for detecting and excluding blood donors with iron deficiency without anemia.

  4. Correlation between donor age and organs transplanted per donor: our experience in Japan.

    Science.gov (United States)

    Ashikari, J; Omiya, K; Konaka, S; Nomoto, K

    2014-05-01

    The shortage of available organs for transplantation is a worldwide issue. To maximize the number of transplantations, increasing the number of organs transplanted per donor (OTPD) is widely recognized as an important factor for improving the shortage. In Japan, we have had 211 donors, 1112 organs transplanted, and 924 recipients receiving the transplants, resulting in 4.4 ± 1.4 recipients receiving transplants per donor and 5.3 ± 1.6 OTPD as of February 2013. Because donor age is a well-recognized factor of donor suitability, we analyzed the correlation between donor age group and OTPD. Only the age group 60 to 69 years and the age group 70 to 79 years were significantly different (P donor under age 70 years has the potential to donate 4.6 to 6.7 organs. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Mannuronic Acids : Reactivity and Selectivity

    NARCIS (Netherlands)

    Codee, Jeroen D. C.; Walvoort, Marthe T. C.; de Jong, Ana-Rae; Lodder, Gerrit; Overkleeft, Herman S.; van der Marel, Gijsbert A.

    2011-01-01

    This review describes our recent studies toward the reactivity and selectivity of mannopyranosyl uronic acid donors, which have been found to be very powerful donors for the construction of beta-mannosidic linkages.

  6. A simplified donor risk index for predicting outcome after deceased donor kidney transplantation.

    Science.gov (United States)

    Watson, Christopher J E; Johnson, Rachel J; Birch, Rhiannon; Collett, Dave; Bradley, J Andrew

    2012-02-15

    We sought to determine the deceased donor factors associated with outcome after kidney transplantation and to develop a clinically applicable Kidney Donor Risk Index. Data from the UK Transplant Registry on 7620 adult recipients of adult deceased donor kidney transplants between 2000 and 2007 inclusive were analyzed. Donor factors potentially influencing transplant outcome were investigated using Cox regression, adjusting for significant recipient and transplant factors. A United Kingdom Kidney Donor Risk Index was derived from the model and validated. Donor age was the most significant factor predicting poor transplant outcome (hazard ratio for 18-39 and 60+ years relative to 40-59 years was 0.78 and 1.49, respectively, Pinformed consent.

  7. A Retrospective Analysis of Apheresis Donor Deferral and Adverse Reactions at a Tertiary Care Centre in India.

    Science.gov (United States)

    Arora, Disha; Garg, Ketan; Kaushik, Ankit; Sharma, Richa; Rawat, D S; Mandal, A K

    2016-11-01

    With increasing demand of platelet component each day, blood bank plays a pivotal role in ensuring supply of safe blood as and when required. Plateletpheresis procedure is a relatively simple, safe and important adjunct to blood bank inventory. However, recruitment of healthy blood donors is a challenge that the health industry is facing today. To determine the reasons and rates of apheresis donor deferral along with investigation of adverse reactions encountered during the procedure. Records of single donor apheresis were retrospectively analysed from 1 st January 2010 to 31 st December 2014. The study was carried out at Blood Bank, Safdarjung Hospital, New Delhi, India. The donor details that were studied included - age, sex, type of donation (voluntary/replacement/ repeat), reason for donor deferral and type of adverse reaction, if encountered during the procedure. Among the 478 donors screened for plateletpheresis procedure during a study period of 5 years, 134 (28.03%) were deferred. Temporary deferrals accounted for majority (93.28%) of the deferrals. Low platelet count (50.75%) was the main reason of donor deferral followed by low haemoglobin (20.89%). Amongst the 344 selected donors, 15 (4.36%) had some type of adverse reaction associated with the procedure. We suggest that the selection criteria for plateletpheresis donors should be revised to deal with shortage of apheresis donors. The criteria regarding minimum pre-procedure platelet count (above1.5 lac/μl) and haemoglobin (above 12.5 g/dl) need to be lowered so as to suit the Indian scenario. The lower adverse reaction rates, 14/344 (4.06%) associated with this procedure encourages safety of donors and is important in recruitment of new donors.

  8. The impact of disclosure on donor gamete participants: donors, intended parents and offspring.

    Science.gov (United States)

    Greenfeld, Dorothy A

    2008-06-01

    The present review examines recent publications that provide insight into how the trend toward nonanonymity and disclosure in gamete donation impacts donors, intended parents, and their donor-conceived children. Recent findings show an increase in donor programs that offer open-identity between donors and offspring. The psychological needs of gamete donors and their attitudes toward disclosure are increasingly given consideration. Qualitative research on how parents of donor gamete offspring make decisions about disclosure reveals that even when couples initially disagree about disclosing to offspring, most ultimately come to a united disclosure decision. The literature on the impact of disclosure on donor gamete offspring has extended to include children conceived through embryo donation and children born as a result of surrogacy. The absence of genetic or gestational link between parents and their child does not have a negative impact on parent-child relationships. Parents through surrogacy tend to disclose the method of family creation to their child, whereas parents through embryo donation tend to be secretive about their child's origins. The trend toward greater openness in gamete donation has been accompanied by an increase in programs offering open-identity donation. In addition, the psychological needs of gamete donors and their attitudes toward disclosure are increasingly being given consideration. Parents of donor gamete offspring give careful thought to their disclosure decisions, and the psychological well being of donor-conceived children does not seem to be impacted by those decisions.

  9. A Comparison of Nutritional Antioxidant Content in Breast Milk, Donor Milk, and Infant Formulas.

    Science.gov (United States)

    Hanson, Corrine; Lyden, Elizabeth; Furtado, Jeremy; Van Ormer, Matthew; Anderson-Berry, Ann

    2016-10-28

    Human milk is the optimal food for human infants, including infants born prematurely. In the event that a mother of a hospitalized infant cannot provide breast milk, donor milk is considered an acceptable alternative. It is known that the macronutrient composition of donor milk is different than human milk, with variable fat content and protein content. However, much less is known about the micronutrient content of donor milk, including nutritional antioxidants. Samples of breast milk from 12 mothers of infants hospitalized in the Newborn Intensive Care Unit until were collected and analyzed for concentrations of nutritional antioxidants, including α-carotene, β-carotene, β-cryptoxanthin, lycopene, lutein + zeaxanthin, retinol, and α-tocopherol. Additionally, a homogenized sample of donor milk available from a commercial milk bank and samples of infant formulas were also analyzed. Concentrations of nutritional antioxidants were measured using high-performance liquid chromatography. Compared to breast milk collected from mothers of hospitalized infants, commercially available donor milk had 18%-53% of the nutritional antioxidant content of maternal breast milk. As donor milk is becoming a common nutritional intervention for the high risk preterm infant, the nutritional antioxidant status of donor milk-fed premature infants and outcomes related to oxidative stress may merit further investigation.

  10. A Comparison of Nutritional Antioxidant Content in Breast Milk, Donor Milk, and Infant Formulas

    Directory of Open Access Journals (Sweden)

    Corrine Hanson

    2016-10-01

    Full Text Available Human milk is the optimal food for human infants, including infants born prematurely. In the event that a mother of a hospitalized infant cannot provide breast milk, donor milk is considered an acceptable alternative. It is known that the macronutrient composition of donor milk is different than human milk, with variable fat content and protein content. However, much less is known about the micronutrient content of donor milk, including nutritional antioxidants. Samples of breast milk from 12 mothers of infants hospitalized in the Newborn Intensive Care Unit until were collected and analyzed for concentrations of nutritional antioxidants, including α-carotene, β-carotene, β-cryptoxanthin, lycopene, lutein + zeaxanthin, retinol, and α-tocopherol. Additionally, a homogenized sample of donor milk available from a commercial milk bank and samples of infant formulas were also analyzed. Concentrations of nutritional antioxidants were measured using high-performance liquid chromatography. Compared to breast milk collected from mothers of hospitalized infants, commercially available donor milk had 18%–53% of the nutritional antioxidant content of maternal breast milk. As donor milk is becoming a common nutritional intervention for the high risk preterm infant, the nutritional antioxidant status of donor milk–fed premature infants and outcomes related to oxidative stress may merit further investigation.

  11. Differences in social representation of blood donation between donors and non-donors: an empirical study.

    Science.gov (United States)

    Guarnaccia, Cinzia; Giannone, Francesca; Falgares, Giorgio; Caligaris, Aldo Ozino; Sales-Wuillemin, Edith

    2015-11-04

    Both donors and non-donors have a positive image of blood donation, so donors and non-donors do not differ regarding their views on donation but do differ in converting their opinion into an active deed of donation. Several studies have identified altruism and empathy as the main factors underlying blood donation. However, a mixture of various motivational factors mould the complex behaviour of donation. This paper presents an exploratory study on differences of social representations of blood donation between blood donors and non-donors, in order to understand the reasons that bring someone to take the decision to become a blood donor. Participants filled in the Adapted Self-Report Altruism Scale, Toronto Empathy Questionnaire and answered a test of verbal association. Descriptive and correlation analyses were carried out on quantitative data, while a prototypic analysis was used for qualitative data. The study was carried out on a convenience sample of 786 individuals, 583 donors (mean age: 35.40 years, SD: 13.01 years; 39.3% female) and 203 non-donors (mean age: 35.10 years, SD: 13.30 years; 67.5% female). Social representations of donors seem to be more complex and articulated than those of non-donors. The terms that appear to be central were more specific in donors (life, needle, blood, help, altruism were the words most associated by non-donors; life, aid, altruism, solidarity, health, love, gift, generosity, voluntary, control, needed, useful, needle were the words most associated by donors). Furthermore, non-donors associated a larger number of terms referring to negative aspects of blood donation. Aspects related to training and the accuracy of any information on blood donation seem to be important in the decision to become a donor and stabilise the behaviour of donation over time, thus ensuring the highest levels of quality and safety in blood establishments.

  12. Double versus single renal allografts from aged donors.

    Science.gov (United States)

    Andrés, A; Morales, J M; Herrero, J C; Praga, M; Morales, E; Hernández, E; Ortuño, T; Rodício, J L; Martínez, M A; Usera, G; Díaz, R; Polo, G; Aguirre, F; Leiva, O

    2000-05-27

    The age limit of the cadaver kidney donors is increasing in response to the growing demand for renal transplantation. Simultaneous double kidney transplantation (SDKT) with kidneys obtained from elderly adults has been proposed to increase the transplantation number and improve its results. However, if SDKT is performed when there are no clear indications, a negative effect could be produced on the total number of transplanted patients as both kidneys would be used for only one recipient. In December 1996 we designed a transplantation protocol to be able to extend the selection of cadaver kidney donors with normal serum creatinine levels without establishing any age limit. A pregraft renal biopsy was always performed to analyze the glomerulosclerosis (GE) percentage whenever the donors were 60 years of age or older. A SDKT was performed in a single recipient when the donor age was 75 years or older or when the donors between 60 and 74 years old had a GE rate of more than 15%. On the contrary, a single kidney transplantation was performed in two different recipients for kidneys from donors between 60 and 74 years of age with a GE rate of less than 15%. Kidneys having GE rates of more than 50% were discarded for transplantation. Donor kidneys from subjects younger than 60 years of age were always used for a single kidney transplantation. Based on the above mentioned protocol, from December 1996 to May 1998, 181 patients received a kidney transplantation in our hospital. These patients were divided into three groups: group I which included the SDKT recipients (n=21), group II or single kidney recipients from 60- to 74-year-old donors (n=40), and group III or recipients from actuarial patient survival (100, 95, and 98%, respectively) or graft survival rates (95, 90, and 93%, respectively). The 6-month serum creatinine levels were excellent in the three groups, although there were significant differences between groups I and II (1.6+/-0.3 vs. 1.9+/-0.6 mg/dl, P75 years

  13. Hybrid collaborative optimization based on selection strategy of initial point and adaptive relaxation

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Aimin; Yin, Xu; Yuan, Minghai [Hohai University, Changzhou (China)

    2015-09-15

    There are two problems in Collaborative optimization (CO): (1) the local optima arising from the selection of an inappropriate initial point; (2) the low efficiency and accuracy root in inappropriate relaxation factors. To solve these problems, we first develop the Latin hypercube design (LHD) to determine an initial point of optimization, and then use the non-linear programming by quadratic Lagrangian (NLPQL) to search for the global solution. The effectiveness of the initial point selection strategy is verified by three benchmark functions with some dimensions and different complexities. Then we propose the Adaptive relaxation collaborative optimization (ARCO) algorithm to solve the inconsistency between the system level and the disciplines level, and in this method, the relaxation factors are determined according to the three separated stages of CO respectively. The performance of the ARCO algorithm is compared with the standard collaborative algorithm and the constant relaxation collaborative algorithm with a typical numerical example, which indicates that the ARCO algorithm is more efficient and accurate. Finally, we propose a Hybrid collaborative optimization (HCO) approach, which integrates the selection strategy of initial point with the ARCO algorithm. The results show that HCO can achieve the global optimal solution without the initial value and it also has advantages in convergence, accuracy and robustness. Therefore, the proposed HCO approach can solve the CO problems with applications in the spindle and the speed reducer.

  14. Hybrid collaborative optimization based on selection strategy of initial point and adaptive relaxation

    International Nuclear Information System (INIS)

    Ji, Aimin; Yin, Xu; Yuan, Minghai

    2015-01-01

    There are two problems in Collaborative optimization (CO): (1) the local optima arising from the selection of an inappropriate initial point; (2) the low efficiency and accuracy root in inappropriate relaxation factors. To solve these problems, we first develop the Latin hypercube design (LHD) to determine an initial point of optimization, and then use the non-linear programming by quadratic Lagrangian (NLPQL) to search for the global solution. The effectiveness of the initial point selection strategy is verified by three benchmark functions with some dimensions and different complexities. Then we propose the Adaptive relaxation collaborative optimization (ARCO) algorithm to solve the inconsistency between the system level and the disciplines level, and in this method, the relaxation factors are determined according to the three separated stages of CO respectively. The performance of the ARCO algorithm is compared with the standard collaborative algorithm and the constant relaxation collaborative algorithm with a typical numerical example, which indicates that the ARCO algorithm is more efficient and accurate. Finally, we propose a Hybrid collaborative optimization (HCO) approach, which integrates the selection strategy of initial point with the ARCO algorithm. The results show that HCO can achieve the global optimal solution without the initial value and it also has advantages in convergence, accuracy and robustness. Therefore, the proposed HCO approach can solve the CO problems with applications in the spindle and the speed reducer

  15. Selective waste collection optimization in Romania and its impact to urban climate

    Science.gov (United States)

    Mihai, Šercǎianu; Iacoboaea, Cristina; Petrescu, Florian; Aldea, Mihaela; Luca, Oana; Gaman, Florian; Parlow, Eberhard

    2016-08-01

    According to European Directives, transposed in national legislation, the Member States should organize separate collection systems at least for paper, metal, plastic, and glass until 2015. In Romania, since 2011 only 12% of municipal collected waste was recovered, the rest being stored in landfills, although storage is considered the last option in the waste hierarchy. At the same time there was selectively collected only 4% of the municipal waste. Surveys have shown that the Romanian people do not have selective collection bins close to their residencies. The article aims to analyze the current situation in Romania in the field of waste collection and management and to make a proposal for selective collection containers layout, using geographic information systems tools, for a case study in Romania. Route optimization is used based on remote sensing technologies and network analyst protocols. Optimizing selective collection system the greenhouse gases, particles and dust emissions can be reduced.

  16. Kidney transplantation from deceased donors with elevated serum creatinine.

    Science.gov (United States)

    Gallinat, Anja; Leerhoff, Sabine; Paul, Andreas; Molmenti, Ernesto P; Schulze, Maren; Witzke, Oliver; Sotiropoulos, Georgios C

    2016-12-01

    Elevated donor serum creatinine has been associated with inferior graft survival in kidney transplantation (KT). The aim of this study was to evaluate the impact of elevated donor serum creatinine on short and long-term outcomes and to determine possible ways to optimize the use of these organs. All kidney transplants from 01-2000 to 12-2012 with donor creatinine ≥ 2 mg/dl were considered. Risk factors for delayed graft function (DGF) were explored with uni- and multivariate regression analyses. Donor and recipient data were analyzed with uni- and multivariate cox proportional hazard analyses. Graft and patient survival were calculated using the Kaplan-Meier method. Seventy-eight patients were considered. Median recipient age and waiting time on dialysis were 53 years and 5.1 years, respectively. After a median follow-up of 6.2 years, 63 patients are alive. 1, 3, and 5-year graft and patient survival rates were 92, 89, and 89 % and 96, 93, and 89 %, respectively. Serum creatinine level at procurement and recipient's dialysis time prior to KT were predictors of DGF in multivariate analysis (p = 0.0164 and p = 0.0101, respectively). Charlson comorbidity score retained statistical significance by multivariate regression analysis for graft survival (p = 0.0321). Recipient age (p = 0.0035) was predictive of patient survival by multivariate analysis. Satisfactory long-term kidney transplant outcomes in the setting of elevated donor serum creatinine ≥2 mg/dl can be achieved when donor creatinine is <3.5 mg/dl, and the recipient has low comorbidities, is under 56 years of age, and remains in dialysis prior to KT for <6.8 years.

  17. Donor-derived HLA antibody production in patients undergoing SCT from HLA antibody-positive donors.

    Science.gov (United States)

    Taniguchi, K; Yoshihara, S; Maruya, E; Ikegame, K; Kaida, K; Hayashi, K; Kato, R; Inoue, T; Fujioka, T; Tamaki, H; Okada, M; Onuma, T; Fujii, N; Kusunoki, Y; Soma, T; Saji, H; Ogawa, H

    2012-10-01

    Pre-existing donor-specific HLA antibodies in patients undergoing HLA-mismatched SCT have increasingly been recognized as a risk factor for primary graft failure. However, the clinical implications of the presence of HLA antibodies in donors remain unknown. We prospectively examined 123 related donors for the presence of HLA antibodies by using a Luminex-based single antigen assay. Of these, 1/57 (1.8%) male, 6/27 (22%) parous female and 0/39 (0%) nonparous female donors were HLA antibody-positive. Then, we determined the presence of HLA antibodies in seven patients who received SCT from antibody-positive donors. Of these, four became HLA antibody-positive after SCT. The specificities of the antibodies that emerged in the patients closely resembled those of the antibodies found in the donors, indicating their production by donor-derived plasma cells. Moreover, the kinetics of the HLA antibody levels were similar in all four patients: levels started increasing within 1 week after SCT and peaked at days 10-21, followed by a gradual decrease. These results suggest that donor-derived HLA antibody production frequently occurs in patients undergoing SCT from antibody-positive donors. Further studies are warranted for clarifying the clinical significance of donor-derived HLA antibodies, including the role of these antibodies in post transplant platelet transfusion refractoriness.

  18. HLA matching in unrelated donor bone marrow transplantation.

    Science.gov (United States)

    Charron, D J

    1996-11-01

    The availability of an HLA-matched sibling donor in only 30% to 35% of patients requiring allogeneic bone marrow transplantation (BMT) has led to the proposal of unrelated donors as an alternative source of bone marrow. The greater HLA incompatibility, which, although present, was undetected until recently in many unrelated donor BMT cases, has resulted in a higher rate of posttransplant complications and impaired acturial survival when compared with HLA-matched sibling BMT. Molecular HLA typing enables us to evaluate the impact of incompatibility at each locus in the outcome of unrelated donor BMT. The overall retrospective data would recommend that HLA-A, -B and -C allelic molecular matching should be implemented in addition to HLA-DR allelic matching. Further retrospective analysis is needed in order to assess which incompatibility or combinations are better tolerated than others. Only the definitive knowledge at the sequence level of the donor and the recipient HLA allelic diversity involved in controlling the allogeneic immune response will allow us to understand the precise biologic rationale of the graft-versus-host disease. Knowledge and control of the HLA incompatibilities should allow us to offset the detrimental effects of histoincompatibility while developing strategies to take advantage of the beneficial graft-versus-leukemia effect. Also the role of minor histocompatibility antigens remains largely unknown and will require careful evaluation before minor antigens can be used as a selection criterion in BMT. Carefully designed prospective studies will enable us to test the impact of each HLA locus. HLA typing and BMT represent a successful example of productive cooperation between basic and clinical sciences that should be pursued for the improvement of the clinical outcome of unrelated donor BMT.

  19. Donor's understanding of the definition of sex as applied to predonation screening questions.

    Science.gov (United States)

    O'Brien, S F; Ram, S S; Yi, Q-L; Goldman, M

    2008-05-01

    Predonation screening questions about sexual risk factors should provide an extra layer of safety from recently acquired infections that may be too early to be detected by testing. Donors are required to read a definition of sex as it applies to predonation screening questions each time they come to donate, but how well donors apply such definitions has not been evaluated. We aimed to determine how donors define sex when answering screening questions. In total, 1297 whole blood donors were asked in a private interview to select from a list of sexual activities which ones they believed were being asked about in sexual background questions. Donors' definitions were coded as under-inclusive, correct or over-inclusive in relation to the blood services' definition. Qualitative interviews were carried out with 21 donors to understand reasoning behind definitions. Most donors had an over-inclusive definition (58.7%) or the correct definition (31.9%). Of the 9.4% of donors who had an under-inclusive definition, 95% included both vaginal and anal sex, but not oral sex. About 9% in each group were first-time donors (P > 0.05) who had never read the definition. The qualitative interviews indicated that donors reason their definition based on their own concept of transmissible disease risk. Donors apply a range of definitions of sex when answering questions about their sexual background. This may be due to different concepts of risk activities, and required reading of the definition has little impact.

  20. ِAnalysis of donor motivations in living donor liver transplantation

    Directory of Open Access Journals (Sweden)

    Hesham eAbdeldayem

    2014-07-01

    Full Text Available Objectives: The introduction of the living donor liver transplantation (LDLT in Egypt as in elsewhere, has raised important psychological conflicts and ethical questions. The objective of this study was to get better understanding of the potential donors’ motives towards LDLT.Methods:This study was conducted on consecutive 193 living –liver donors who underwent partial hepatectomy as donors for LDLT during the period between April 2003 and January 2013, at the National Liver Institute Menoufeyia University, Egypt. Potential donors were thoroughly evaluated preoperatively through a screening questionnaire and interviews as regard their demographic data, relationship to the potential recipient and motives towards proceeding to surgery. They were assured that the information shared between them and the transplant centre is confidential. Results.The donors’ mean age was 25.53± 6.39 years with a range of 18-45 years. Males represented 64.7 % and females were 35.3%. The most common donors (32.1%, n_62, were sons and daughters to their parents (sons: n_43, daughters: n_19 while parents to their offsprings represent 15% (mothers: n_21, fathers: n_8. Brothers and sisters represent 16.5 % (brothers: n_22, sisters: n_10. Nephews & nieces giving their uncles or aunts were 14%. The number of wives donating to their husbands was 11 (5.7%. Interestingly, there was no single husband who donated his wife. Among the remaining donors, there were 11 cousins & one uncle. Unrelated donors were 20 (10.4%. Several factors seemed to contribute to motivation for donation: the seriousness of the potential recipient condition, the relationship and personal history of the donor to the potential recipient, the religious beliefs, the trust in the health care system, and family dynamics and obligations.Conclusions. Absolute absence of coercion on the living-liver donor’s motives may not be realistic because of the serious condition of the potential recipient. It is

  1. Mathematical Optimization Algorithm for Minimizing the Cost Function of GHG Emission in AS/RS Using Positive Selection Based Clonal Selection Principle

    Science.gov (United States)

    Mahalakshmi; Murugesan, R.

    2018-04-01

    This paper regards with the minimization of total cost of Greenhouse Gas (GHG) efficiency in Automated Storage and Retrieval System (AS/RS). A mathematical model is constructed based on tax cost, penalty cost and discount cost of GHG emission of AS/RS. A two stage algorithm namely positive selection based clonal selection principle (PSBCSP) is used to find the optimal solution of the constructed model. In the first stage positive selection principle is used to reduce the search space of the optimal solution by fixing a threshold value. In the later stage clonal selection principle is used to generate best solutions. The obtained results are compared with other existing algorithms in the literature, which shows that the proposed algorithm yields a better result compared to others.

  2. Positive serology for viral hepatitis and donor self-exclusion in Southern Brazil

    Directory of Open Access Journals (Sweden)

    Julia De Luca Maccarini

    2013-07-01

    Full Text Available Introduction Despite the great advances in serological testing for transfusion-transmitted infections, the selection of blood donors by blood bank operators remains the only way to avoid transmission within the testing window period. Part of this selection is the self-exclusion form, on which the donors can exclude their blood from donation without any explanation. This study assessed the clinical and epidemiological characteristics related to positivity for viral hepatitis and to the use of the confidential self-exclusion (CSE form. Methods This transversal study analyzed the data collected from blood donors' files in a hospital in Southern Brazil. Univariate and multivariate analyses identified the clinical and epidemiological variables related to positive serologies of viral hepatitis and to whether the donor was self-excluded. Results Of the 3,180 donors included in this study, 0.1% tested positive for HBsAg, 2.1% for anti-HBc, and 0.9% for anti-HCV. When the 93 donors with positive serologies for viral hepatitis were compared with those who were negative, a greater proportion of the positive serology group was found to have had a history of blood transfusions (OR=4.908; 95%CI=1.628 - 14.799; p<0.01, had repeatedly donated (OR=2.147; 95%CI=1.236 - 3.729; p<0.01, and used the CSE form for self-exclusion (OR=7.139; 95%CI=2.045 - 24.923; p<0.01. No variables were independently associated with self-exclusion. Conclusions A history of blood transfusion, repeated donations, and self-exclusion are factors that should be considered during viral hepatitis screenings in blood banks.

  3. Optimal portfolio selection for general provisioning and terminal wealth problems

    NARCIS (Netherlands)

    van Weert, K.; Dhaene, J.; Goovaerts, M.

    2010-01-01

    In Dhaene et al. (2005), multiperiod portfolio selection problems are discussed, using an analytical approach to find optimal constant mix investment strategies in a provisioning or a savings context. In this paper we extend some of these results, investigating some specific, real-life situations.

  4. Optimal portfolio selection for general provisioning and terminal wealth problems

    NARCIS (Netherlands)

    van Weert, K.; Dhaene, J.; Goovaerts, M.

    2009-01-01

    In Dhaene et al. (2005), multiperiod portfolio selection problems are discussed, using an analytical approach to find optimal constant mix investment strategies in a provisioning or savings context. In this paper we extend some of these results, investigating some specific, real-life situations. The

  5. Selection of an optimal neural network architecture for computer-aided detection of microcalcifications - Comparison of automated optimization techniques

    International Nuclear Information System (INIS)

    Gurcan, Metin N.; Sahiner, Berkman; Chan Heangping; Hadjiiski, Lubomir; Petrick, Nicholas

    2001-01-01

    Many computer-aided diagnosis (CAD) systems use neural networks (NNs) for either detection or classification of abnormalities. Currently, most NNs are 'optimized' by manual search in a very limited parameter space. In this work, we evaluated the use of automated optimization methods for selecting an optimal convolution neural network (CNN) architecture. Three automated methods, the steepest descent (SD), the simulated annealing (SA), and the genetic algorithm (GA), were compared. We used as an example the CNN that classifies true and false microcalcifications detected on digitized mammograms by a prescreening algorithm. Four parameters of the CNN architecture were considered for optimization, the numbers of node groups and the filter kernel sizes in the first and second hidden layers, resulting in a search space of 432 possible architectures. The area A z under the receiver operating characteristic (ROC) curve was used to design a cost function. The SA experiments were conducted with four different annealing schedules. Three different parent selection methods were compared for the GA experiments. An available data set was split into two groups with approximately equal number of samples. By using the two groups alternately for training and testing, two different cost surfaces were evaluated. For the first cost surface, the SD method was trapped in a local minimum 91% (392/432) of the time. The SA using the Boltzman schedule selected the best architecture after evaluating, on average, 167 architectures. The GA achieved its best performance with linearly scaled roulette-wheel parent selection; however, it evaluated 391 different architectures, on average, to find the best one. The second cost surface contained no local minimum. For this surface, a simple SD algorithm could quickly find the global minimum, but the SA with the very fast reannealing schedule was still the most efficient. The same SA scheme, however, was trapped in a local minimum on the first cost

  6. Blood donor recruitment strategies and their impact on blood safety in Egypt.

    Science.gov (United States)

    Hussein, Eiman

    2014-02-01

    Because of the high incidence of HCV, blood safety presents a serious challenge in Egypt. Given the constrained economy which limits the implementation of nucleic acid amplification technology, proper recruitment of blood donors becomes of paramount importance. To evaluate the effectiveness of blood donor recruitment strategies, the seroprevalence of positive infectious markers among blood donors was studied. Donors' records covering the period from 2006-2012 were reviewed. Blood donations were screened for HCV antibodies, HBs antigen (HBsAg), HIV-1 and 2 and syphilis antibodies. Of 308,762 donors, 63.4% were voluntary donors (VD). VD of 2011-2012 were significantly younger than family replacement donors (RD) .The overall prevalences of HCV antibodies, HBsAg, HIV and syphilis antibodies were 4.3%, 1.22%, 0.07%, and 0.13%, respectively. All tested markers (except HIV) were significantly higher among RD, when compared to VD (P<0.0001). A consistent steady trend for decrease in HCV seropositivity was observed in RD and VD from 8.9% and 4.2% to 3.8% and 1.5%, respectively. A trend for decrease in HBsAg was demonstrated in VD from 1.2% to 0.53%. The decreasing trends in HCV antibody and HBs antigen is promising and may reflect the improved donor selection criteria. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Joint Optimization of Receiver Placement and Illuminator Selection for a Multiband Passive Radar Network.

    Science.gov (United States)

    Xie, Rui; Wan, Xianrong; Hong, Sheng; Yi, Jianxin

    2017-06-14

    The performance of a passive radar network can be greatly improved by an optimal radar network structure. Generally, radar network structure optimization consists of two aspects, namely the placement of receivers in suitable places and selection of appropriate illuminators. The present study investigates issues concerning the joint optimization of receiver placement and illuminator selection for a passive radar network. Firstly, the required radar cross section (RCS) for target detection is chosen as the performance metric, and the joint optimization model boils down to the partition p -center problem (PPCP). The PPCP is then solved by a proposed bisection algorithm. The key of the bisection algorithm lies in solving the partition set covering problem (PSCP), which can be solved by a hybrid algorithm developed by coupling the convex optimization with the greedy dropping algorithm. In the end, the performance of the proposed algorithm is validated via numerical simulations.

  8. Tuning the Phosphoryl Donor Specificity of Dihydroxyacetone Kinase from ATP to Inorganic Polyphosphate. An Insight from Computational Studies

    Directory of Open Access Journals (Sweden)

    Israel Sánchez-Moreno

    2015-11-01

    Full Text Available Dihydroxyacetone (DHA kinase from Citrobacter freundii provides an easy entry for the preparation of DHA phosphate; a very important C3 building block in nature. To modify the phosphoryl donor specificity of this enzyme from ATP to inorganic polyphosphate (poly-P; a directed evolution program has been initiated. In the first cycle of evolution, the native enzyme was subjected to one round of error-prone PCR (EP-PCR followed directly (without selection by a round of DNA shuffling. Although the wild-type DHAK did not show activity with poly-P, after screening, sixteen mutant clones showed an activity with poly-phosphate as phosphoryl donor statistically significant. The most active mutant presented a single mutation (Glu526Lys located in a flexible loop near of the active center. Interestingly, our theoretical studies, based on molecular dynamics simulations and hybrid Quantum Mechanics/Molecular Mechanics (QM/MM optimizations, suggest that this mutation has an effect on the binding of the poly-P favoring a more adequate position in the active center for the reaction to take place.

  9. [Liver engineering as a new source of donor organs : A systematic review].

    Science.gov (United States)

    Mußbach, F; Dahmen, U; Dirsch, O; Settmacher, U

    2016-06-01

    Organ engineering is a new strategy to cope with the shortage of donor organs. A functional scaffold from explanted organs is prepared by removing all cellular components (decellularization) and the reseeding (repopulation) of the organ scaffold to generate a functional organ in vitro for transplantation. This technique was also applied to the liver (liver engineering). Outline of the current state of the art and resulting approaches for future research strategies. Systematic review according to the PRISMA guidelines: a PubMed-based literature search (search terms liver, decellularization), selection of relevant articles based on predetermined criteria for relevance (e.g. decellularization, repopulation and transplantation), extraction and critical appraisal of data and results concerning the conditions for decellularization, repopulation and transplantation. Decellularization was successfully performed in small and large animal models. Hepatocytes as well as stem cells and hepatic cell lines were applied for repopulation and 7 publications could show the successful transplantation of acellular and repopulated organ scaffolds. The current scientific need for further studies concerning the source of donor organs, optimization of the decellularization process, the cell type for the reseeding process and the establishment of the optimal conditions for the repopulation of the scaffold is still tremendous. For successful recellularization of the liver three goals need to be achieved: (1) reseeding of the organ scaffold with a sufficient amount of parenchymal cells, (2) endothelialization of the vascular tree to ensure the supply of oxygen and nutrients to parenchymal cells and (3) an appropriate epithelialization of the biliary tree. In order to progress to clinical trials a suitable transplantation model to verify the function of the organ constructs must be established. Liver engineering using biological cell-free organ scaffolds represents a scientific and ethical

  10. Optimal relay selection and power allocation for cognitive two-way relaying networks

    KAUST Repository

    Pandarakkottilil, Ubaidulla

    2012-06-01

    In this paper, we present an optimal scheme for power allocation and relay selection in a cognitive radio network where a pair of cognitive (or secondary) transceiver nodes communicate with each other assisted by a set of cognitive two-way relays. The secondary nodes share the spectrum with a licensed primary user (PU), and each node is assumed to be equipped with a single transmit/receive antenna. The interference to the PU resulting from the transmission from the cognitive nodes is kept below a specified limit. We propose joint relay selection and optimal power allocation among the secondary user (SU) nodes achieving maximum throughput under transmit power and PU interference constraints. A closed-form solution for optimal allocation of transmit power among the SU transceivers and the SU relay is presented. Furthermore, numerical simulations and comparisons are presented to illustrate the performance of the proposed scheme. © 2012 IEEE.

  11. High mortality in diabetic recipients of high KDPI deceased donor kidneys.

    Science.gov (United States)

    Pelletier, Ronald P; Pesavento, Todd E; Rajab, Amer; Henry, Mitchell L

    2016-08-01

    Deceased donor (DD) kidney quality is determined by calculating the Kidney Donor Profile Index (KDPI). Optimizing high KDPI (≥85%) DD transplant outcome is challenging. This retrospective study was performed to review our high KDPI DD transplant results to identify clinical practices that can improve future outcomes. We retrospectively calculated the KDPI for 895 DD kidney recipients transplanted between 1/2002 and 11/2013. Age, race, body mass index (BMI), retransplantation, gender, diabetes (DM), dialysis time, and preexisting coronary artery disease (CAD) (previous myocardial infarction (MI), coronary artery bypass (CABG), or stenting) were determined for all recipients. About 29.7% (266/895) of transplants were from donors with a KDPI ≥85%. By Cox regression older age, diabetes, female gender, and dialysis time >4 years correlated with shorter patient survival time. Diabetics with CAD who received a high KDPI donor kidney had a significantly increased risk of death (HR 4.33 (CI 1.82-10.30), P=.001) compared to low KDPI kidney recipients. The Kaplan-Meier survival curve for diabetic recipients of high KDPI kidneys was significantly worse if they had preexisting CAD (P<.001 by log-rank test). Patient survival using high KDPI donor kidneys may be improved by avoiding diabetic candidates with preexisting CAD. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. Perioperative period in cardiac transplantation from donors with brain death due to methanol poisoning

    Directory of Open Access Journals (Sweden)

    V. N. Poptsov

    2017-01-01

    Full Text Available The successful use of donor hearts from people died of methanol poisoning helps reducing the deficit of donor organs for patients requiring urgent cardiac transplantation [3]. We present our experience of successful cardiac transplantations from 2 donors who died due to methanol poisoning. Given the possibility of performing a cardiac transplant from this group of donors a protocol has been developed at the V.I. Shumakov Federal Research Center of Transplantology and Artificial Organs of the Ministry of Healthcare of the Russian Federation which includes clinical, laboratory and instrumental criteria for the selection of heart donor and recipient. The possibility of delayed onset myocardial contractile dysfunction due to methanol poisoning means that a longer conditioningperiod is vital as well as compulsory clinical, laboratory and expert chocardiographic examinations of the potential donor heart.

  13. Donor of winter rye short stem (Secale cereale L. Gnom 1

    Directory of Open Access Journals (Sweden)

    В. В. Скорик

    2013-08-01

    Full Text Available The article proves that the genetic cluster analysis using of parents – offspring system at the period of 38 generations of directional intentional selection to short stem, the height of winter rye plants has been reduced less than 90 cm with simultaneously productivity integral components increasing. Directional selection on parent plants short stem has revealed pleiotropic effects to increasing averages of productivity yield capacity, spike length, flowers number, grains, and short stem and simultaneously its productivity reducing, plant and weight reducing of 100 direct descendants grains. Plant height donor of short stem Gnome 1 has been controlled prevailing by genetic factors and has been less influenced by environmental conditions. Selection by enlargement of elite plants grains has predetermined genetically increasing of the average height of families in the next generation without the concept selection requirements satisfaction. Therefore, the directed selections, by the structural analysis results, are annually held in two phases, first – to the expressed short stem and then among of them – to the high weight of 100 grains per plant and desirable productivity elements. A creative dominant short stem donor with stems up to 90 cm and a weight of 100 grains per plant more than 4.0 g has been made. A short stem spike shortness donor Dwarf 1possesses a significant reserve of common genetic mutation of quantitative characteristics, which can be used by direct and indirect selection. This population has been represented by its large amount, in order to enhance capabilities of directional selection plants short stem providing with the desired productivity components during the studying. Informative additive genetic cluster analysis is high. Plants productivity is considered to be extremely complicated selection characteristics, including many component constituents parts related genetically. One of these traits changing inevitably causes

  14. Optimal Licensing Contracts with Adverse Selection and Informational Rents

    Directory of Open Access Journals (Sweden)

    Daniela MARINESCU

    2011-06-01

    Full Text Available In the paper we analyse a model for determining the optimal licensing contract in both situations of symmetric and asymmetric information between the license’s owner and the potential buyer. Next we present another way of solving the corresponding adverse selection model, using the informational rents as variables. This approach is different from that of Macho-Stadler and Perez-Castrillo.

  15. Optimal Subinterval Selection Approach for Power System Transient Stability Simulation

    Directory of Open Access Journals (Sweden)

    Soobae Kim

    2015-10-01

    Full Text Available Power system transient stability analysis requires an appropriate integration time step to avoid numerical instability as well as to reduce computational demands. For fast system dynamics, which vary more rapidly than what the time step covers, a fraction of the time step, called a subinterval, is used. However, the optimal value of this subinterval is not easily determined because the analysis of the system dynamics might be required. This selection is usually made from engineering experiences, and perhaps trial and error. This paper proposes an optimal subinterval selection approach for power system transient stability analysis, which is based on modal analysis using a single machine infinite bus (SMIB system. Fast system dynamics are identified with the modal analysis and the SMIB system is used focusing on fast local modes. An appropriate subinterval time step from the proposed approach can reduce computational burden and achieve accurate simulation responses as well. The performance of the proposed method is demonstrated with the GSO 37-bus system.

  16. Validation of KDRI/KDPI for the selection of expanded criteria kidney donors

    Directory of Open Access Journals (Sweden)

    Raimundo M. García del Moral Martín

    2018-05-01

    Full Text Available Introduction: KDRI/KDPI are tools use in kidney donor evaluation. It has been proposed as a substitute of, or complementary to preimplantation renal biopsy. These scores have not been validated in Spain. Objective: (1 To investigate the concordance between KDPI and histological scores (preimplantation renal biopsy and (2 to assess the relationship between KDRI, KDPI and histological score on graft survival in the expanded criteria donors group. Methodology: Retrospective cohort study from 1 January 1998 to 31 December 2010. Results: During the study 120 donors were recruited, that resulted in 220 preimplantation renal biopsies. 144 (65% grafts were considered suitable for kidney transplantation. 76 (34.5% were discarded. Median follow up has been 6.4 years (sd 3.9. Median age 63.1 years (sd 8.2, males (145; 65.9%, non-diabetic (191; 86.8% and without another cardiovascular risk factors (173; 78.6%. 153 (69.5% donors died of cerebrovascular disease. There were significant differences in KDRI/KDPI score in both groups 1.56/89 (sd 0.22 vs 1.66/93 (sd 0.15, p < 0.01. The KDPI showed moderate concordance and correlation with the histological score (AUC 0.64/correlation coefficient 0.24, p < 0.01. KDPI (HR 24.3, p < 0.01 and KDRI (HR 23.3, p < 0.01 scores were associated with graft survival in multivariate analysis. Conclusion: (1 KPDI and histological scores show moderate concordance. The utility of both scores as combined tools it has to be determined. (2 KDPI score, and especially KDRI score, are valid for estimating graft survival and combined with the biopsy can help to individualized decision making in the expanded criteria donors pool. Resumen: Introducción: El KDRI y su variante KDPI son dos herramientas utilizadas para la valoración del donante renal. Se ha propuesto la utilidad del KDPI como sustituto/complementario a la biopsia renal preimplantación. Estos scores no están validados en España. Objetivo: 1 Investigar la

  17. Inter- and Intrapersonal Barriers to Living Donor Kidney Transplant among Black Recipients and Donors.

    Science.gov (United States)

    Davis, LaShara A; Grogan, Tracy M; Cox, Joy; Weng, Francis L

    2017-08-01

    End-stage renal disease (ESRD) is more common among Blacks, but Blacks are less likely to receive a live donor kidney transplant (LDKT). The objective of this study is to identify barriers and coping mechanisms that Black LDKT recipients and donors experienced while receiving or donating a kidney. A qualitative study was conducted using structured interviews. Thematic analysis was used for data interpretation. All 20 participants identified as Black, with two participants identifying themselves as multiracial. The mean age for the 14 recipients was 60, and the average age for the 6 living donors was 47. Themes emerging from the data suggest both recipients and donors faced barriers in the LDKT experience. Recipients faced barriers associated with their denial and avoidance of the severity of their ESRD, their desire to maintain the privacy of their health status, and their refusal to approach potential donors. Donors encountered negative responses from others about the donors' desire to donate and the initial refusal of recipients to accept a LDKT offer. Recipients identified faith as a coping mechanism, while donors identified normalization of donation as their method of coping. Various types of social support helped donors and recipients navigate the transplant process. Black LDKT recipients and donors must overcome barriers prior to receiving or donating a kidney. Most of these barriers arise from communication and interactions with others that are either lacking or undesirable. Future interventions to promote LDKT among Blacks may benefit by specifically targeting these barriers.

  18. A Cu-Zn nanoparticle promoter for selective carbon dioxide reduction and its application in visible-light-active Z-scheme systems using water as an electron donor.

    Science.gov (United States)

    Yin, Ge; Sako, Hiroshi; Gubbala, Ramesh V; Ueda, Shigenori; Yamaguchi, Akira; Abe, Hideki; Miyauchi, Masahiro

    2018-04-17

    Selective carbon dioxide photoreduction to produce formic acid was achieved under visible light irradiation using water molecules as electron donors, similar to natural plants, based on the construction of a Z-scheme light harvesting system modified with a Cu-Zn alloy nanoparticle co-catalyst. The faradaic efficiency of our Z-scheme system for HCOOH generation was over 50% under visible light irradiation.

  19. SYSTEMIC COMPLICATIONS AND THEIR RISK FACTORS AMONG TEHRANIAN BLOOD DONOR, 2005

    Directory of Open Access Journals (Sweden)

    F. Majlessi

    2008-06-01

    Full Text Available The systemic complications of blood donation are the first reasons why patients fail to return for further blood donation. This study was designed to determine the frequency of these complications and their associated risk factors among blood donors in Tehran. Also, we aimed to provide suitable methods to decrease the frequency of these adverse events, thereby eliminating the most important causes of withdrawal, while maintaining the health of the donors. This analytical descriptive cross-sectional study was performed on 554 blood donors who had donated blood from February 2005 through September 2005 in four fixed blood donation bases and four mobile blood collection buses. Each base was considered as a stratum, and a stratified random sampling proportional to size was done to select the donors. Results showed donor reaction rate to be 13.4%, the most common of which were blackout of vision (7%, dizziness (6.3%, fatigue (6.1% and nausea (1.8%. There was no significant relationship between the incidence of these complications and type of base blood donation or fasting at the time of blood donation. Logistic Regression analysis showed that sex, condition of blood donor, exercise or walking, duration of donation, and practice to recommendation had significant effects on the odds ratio of systemic complication. Regarding the frequency values derived for the different systemic complications it can be concluded that attention to risk factors of these complications and their control can help encourage donors to become repeated donors as well as to prevent their withdrawal for further blood donation.

  20. Halide-mediated regioselective 6-O-glycosylation of unprotected hexopyranosides with perbenzylated glycosyl bromide donors

    DEFF Research Database (Denmark)

    Niedbal, Dominika Alina; Madsen, Robert

    2016-01-01

    The regio- and stereoselective glycosylation at the 6-position in 2,3,4,6-unprotected hexopyranosides has been investigated with dibutyltin oxide as the directing agent. Perbenzylated hexopyranosyl bromides were employed as the donors and the glycosylations were promoted by tetrabutylammonium...... bromide. The couplings were completely selective for both glucose and galactose donors and acceptors as long as the stannylene acetal of the acceptor was soluble in dichloromethane. This gave rise to a number of 1,2-cis-linked disaccharides in reasonable yields. Mannose donors and acceptors, on the other...

  1. Donor-Derived Myeloid Sarcoma in Two Kidney Transplant Recipients from a Single Donor

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    Amudha Palanisamy

    2015-01-01

    Full Text Available We report the rare occurrence of donor-derived myeloid sarcoma in two kidney transplant patients who received organs from a single deceased donor. There was no evidence of preexisting hematologic malignancy in the donor at the time of organ recovery. Both recipients developed leukemic involvement that appeared to be limited to the transplanted organ. Fluorescence in situ hybridization (FISH and molecular genotyping analyses confirmed that the malignant cells were of donor origin in each patient. Allograft nephrectomy and immediate withdrawal of immunosuppression were performed in both cases; systemic chemotherapy was subsequently administered to one patient. Both recipients were in remission at least one year following the diagnosis of donor-derived myeloid sarcoma. These cases suggest that restoration of the immune system after withdrawal of immunosuppressive therapy and allograft nephrectomy may be sufficient to control HLA-mismatched donor-derived myeloid sarcoma without systemic involvement.

  2. Energy status of pig donor organs after ischemia is independent of donor type.

    Science.gov (United States)

    Stadlbauer, Vanessa; Stiegler, Philipp; Taeubl, Philipp; Sereinigg, Michael; Puntschart, Andreas; Bradatsch, Andrea; Curcic, Pero; Seifert-Held, Thomas; Zmugg, Gerda; Stojakovic, Tatjana; Leopold, Barbara; Blattl, Daniela; Horki, Vera; Mayrhauser, Ursula; Wiederstein-Grasser, Iris; Leber, Bettina; Jürgens, Günther; Tscheliessnigg, Karlheinz; Hallström, Seth

    2013-04-01

    Literature is controversial whether organs from living donors have a better graft function than brain dead (BD) and non-heart-beating donor organs. Success of transplantation has been correlated with high-energy phosphate (HEP) contents of the graft. HEP contents in heart, liver, kidney, and pancreas from living, BD, and donation after cardiac death in a pig model (n=6 per donor type) were evaluated systematically. BD was induced under general anesthesia by inflating a balloon in the epidural space. Ten hours after confirmation, organs were retrieved. Cardiac arrest was induced by 9V direct current. After 10min of ventricular fibrillation without cardiac output, mechanical and medical reanimation was performed for 30min before organ retrieval. In living donors, organs were explanted immediately. Freeze-clamped biopsies were taken before perfusion with Celsior solution (heart) or University of Wisconsin solution (abdominal organs) in BD and living donors or with Histidine-Tryptophan-Ketoglutaric solution (all organs) in non-heart-beating donors, after perfusion, and after cold ischemia (4h for heart, 6h for liver and pancreas, and 12h for kidney). HEPs (adenosine triphosphate, adenosine diphosphate, adenosine monophosphate, and phosphocreatine), xanthine, and hypoxanthine were measured by high-performance liquid chromatography. Energy charge and adenosine triphosphate-to-adenosine diphosphate ratio were calculated. After ischemia, organs from different donor types showed no difference in energy status. In all organs, a decrease of HEP and an increase in hypoxanthine contents were observed during perfusion and ischemia, irrespective of the donor type. Organs from BD or non-heart-beating donors do not differ from living donor organs in their energy status after average tolerable ischemia. Copyright © 2013 Elsevier Inc. All rights reserved.

  3. Single versus dual renal transplantation from donors with significant arteriosclerosis on pre-implant biopsy.

    Science.gov (United States)

    Kayler, Liise K; Mohanka, Ravi; Basu, Amit; Shapiro, Ron; Randhawa, Parmjeet S

    2009-01-01

    Transplantation of kidneys from donor with arteriosclerosis seen on pre-implantation biopsy has not been well studied. We retrospectively evaluated 20 dual kidney transplant (DKT) and 28 single (SKT) kidney transplant recipients with >or=12 months follow-up from donors with moderate arteriosclerosis (>or=25% luminal diameter narrowing). Death censored graft survival was 100% and 79%, respectively (p = 0.0339). DKT recipients had significantly lower mean creatinine levels at one, three, six, and nine months and spent somewhat less time on the waiting list (181 +/- 160 vs. 318 +/- 306 d, p = 0.1429). DKT patients received kidneys from significantly older donors (64 +/- 7 vs. 54 +/- 11 yr; p = 0.0012), proportionately more expanded criteria donors (95% vs. 54%; p = 0.0029), and more donors with hypertension (81% vs. 48%, p = 0.0344) and death related to cerebrovascular accident (100% vs. 71%, p = 0.0143); however, more DKT kidneys underwent machine perfusion (95% vs. 57%, p = 0.0068). Baseline recipient variables were comparable between the two groups including age, race, gender, retransplantation, and HLA mismatch. Pre-implant biopsy was notable for similar frequencies of moderate interstitial fibrosis (10% vs. 14%, respectively) and glomerulosclerosis. Among recipients of deceased-donor kidneys with >25% arteriosclerosis, short-term outcomes after DKT were superior to that of SKT grafts. This approach may help to expand the donor-organ pool while optimizing outcomes.

  4. Iteration particle swarm optimization for contract capacities selection of time-of-use rates industrial customers

    International Nuclear Information System (INIS)

    Lee, Tsung-Ying; Chen, Chun-Lung

    2007-01-01

    This paper presents a new algorithm for solving the optimal contract capacities of a time-of-use (TOU) rates industrial customer. This algorithm is named iteration particle swarm optimization (IPSO). A new index, called iteration best is incorporated into particle swarm optimization (PSO) to improve solution quality and computation efficiency. Expanding line construction cost and contract recovery cost are considered, as well as demand contract capacity cost and penalty bill, in the selection of the optimal contract capacities. The resulting optimal contract capacity effectively reaches the minimum electricity charge of TOU rates users. A significant reduction in electricity costs is observed. The effects of expanding line construction cost and contract recovery cost on the selection of optimal contract capacities can also be estimated. The feasibility of the new algorithm is demonstrated by a numerical example, and the IPSO solution quality and computation efficiency are compared to those of other algorithms

  5. Frequency and risk factors for donor reactions in an anonymous blood donor survey.

    Science.gov (United States)

    Goldman, Mindy; Osmond, Lori; Yi, Qi-Long; Cameron-Choi, Keltie; O'Brien, Sheila F

    2013-09-01

    Adverse donor reactions can result in injury and decrease the likelihood of donor return. Reaction reports captured in the blood center's database provide an incomplete picture of reaction rates and risk factors. We performed an anonymous survey, mailed to 40,000 donors in 2008, including questions about symptoms, height, weight, sex, and donation status. Reaction rates were compared to those recorded in our database. Possible risk factors were assessed for various reactions. The response rate was 45.5%. A total of 32% of first-time and 14% of repeat donors reported having any adverse symptom, most frequently bruising (84.9 per 1000 donors) or feeling faint or weak (66.2 per 1000). Faint reactions were two to eight times higher than reported in our database, although direct comparison was difficult. Younger age, female sex, and first-time donation status were risk factors for systemic and arm symptoms. In females, low estimated blood volume (EBV) was a risk factor for systemic symptoms. Only 51% of donors who consulted an outside physician also called Canadian Blood Services. A total of 10% of first-time donors with reactions found adverse effects information inadequate. This study allowed us to collect more information about adverse reactions, including minor symptoms and delayed reactions. Based on our findings of the risk factors and frequency of adverse reactions, we are implementing more stringent EBV criteria for younger donors and providing more detailed information to donors about possible adverse effects and their management. © 2012 American Association of Blood Banks.

  6. Alternative Donor Graft Sources for Adults with Hematologic Malignancies: A Donor for All Patients in 2017!

    Science.gov (United States)

    Kindwall-Keller, Tamila L; Ballen, Karen K

    2017-09-01

    Hematopoietic stem cell transplant (HSCT) is potentially curative for a wide variety of malignant diseases, including acute and leukemias, lymphoma, and myelodysplasia. Choice of a stem cell donor is dependent on donor availability, donor compatibility and health, recipient disease type, and recipient condition. Current sources of stem cell donation for HSCT are matched sibling donors (MSDs), matched unrelated donors (MUDs), 1-antigen mismatched unrelated donors (MMUDs), haploidentical donors (haplo), and umbilical cord blood (UCB) units. Historically, preferred donors for HSCT have been human leukocyte antigen (HLA)-matched sibling donors; however, only about 30% of U.S. patients will have a MSD available. The majority of patients referred for HSCT will require an alternative donor graft: MUD, MMUD, UCB, or haplo. The likelihood of finding a MUD varies depending on the ethnicity of the recipient. White Caucasians of European descent have the greatest chance of finding a MUD. Chances of finding a MUD are significantly less for African-American or Hispanic recipients due to HLA polymorphisms. Therefore, MMUD, UCB, and haplo donor graft sources expand the donor pool for recipients who do not have a MSD or MUD available. Given the variety of different donor stem cell sources available today, nearly every patient who needs an allogeneic HSCT has a potential donor in 2017. All transplant-eligible patients with hematologic malignancies should be evaluated by a transplant center to determine if HSCT is a viable treatment option for their underlying disease process. The goal of this review is to increase the awareness of oncology practitioners to the availability of alternative donor stem cell transplants for patients with hematologic malignancies. Despite new agents, stem cell transplant remains the only curative therapy for many patients with acute and chronic leukemia, myelodysplasia, and lymphoma. Given the variety of different donor stem cell sources available today

  7. Optimal processing pathway selection for microalgae-based biorefinery under uncertainty

    DEFF Research Database (Denmark)

    Rizwan, Muhammad; Zaman, Muhammad; Lee, Jay H.

    2015-01-01

    We propose a systematic framework for the selection of optimal processing pathways for a microalgaebased biorefinery under techno-economic uncertainty. The proposed framework promotes robust decision making by taking into account the uncertainties that arise due to inconsistencies among...... and shortage in the available technical information. A stochastic mixed integer nonlinear programming (sMINLP) problem is formulated for determining the optimal biorefinery configurations based on a superstructure model where parameter uncertainties are modeled and included as sampled scenarios. The solution...... the accounting of uncertainty are compared with respect to different objectives. (C) 2015 Elsevier Ltd. All rights reserved....

  8. Laparoscopic donor nephrectomy versus open donor nephrectomy: Recipient′s perspective

    Directory of Open Access Journals (Sweden)

    Tukaram E Jamale

    2012-01-01

    Full Text Available Effects of laparoscopic donor nephrectomy (LDN on graft function, especially early post-transplant, have been controversial. To assess and compare early and late graft function in kidneys procured by open and laparoscopic methods, a retrospective observational study was carried out on 37 recipients-donors who underwent LDN after introduction of this technique in February 2007 at our center, a tertiary care nephrology referral center. Demographic, immunological and intraoperative variables as well as immunosuppressive protocols and number of human leukocyte antigen (HLA mismatches were noted. Early graft function was assessed by serum creatinine on Days two, five, seven, 14 and 28 and at the time of discharge. Serum creatinine values at three months and at one year post-transplant were considered as the surrogates of late graft function. Data obtained were compared with the data from 33 randomly selected kidney transplants performed after January 2000 by the same surgical team, in whom open donor nephrectomy was used. Pearson′s chi square test, Student′s t test and Mann-Whitney U test were used for statistical analysis. Early graft function (serum creatinine on Day five 2.15 mg/dL vs 1.49 mg/dL, P = 0.027 was poorer in the LDN group. Late graft function as assessed by serum creatinine at three months (1.45 mg/dL vs 1.31 mg/dL, P = 0.335 and one year (1.56 mg/dL vs 1.34 mg/dL, P = 0.275 was equivalent in the two groups. Episodes of early acute graft dysfunction due to acute tubular necrosis were significantly higher in the LDN group (37.8% vs 12.1%, Z score 2.457, P = 0.014. Warm ischemia time was significantly prolonged in the LDN group (255 s vs 132.5 s, P = 0.002. LDN is associated with slower recovery of graft function and higher incidence of early acute graft dysfunction due to acute tubular necrosis. Late graft function at one year is however comparable.

  9. Family Communication about Donor Conception: A Qualitative Study with Lesbian Parents.

    Science.gov (United States)

    Van Parys, Hanna; Wyverkens, Elia; Provoost, Veerle; De Sutter, Petra; Pennings, Guido; Buysse, Ann

    2016-03-01

    In this qualitative study of 10 lesbian couples who built their families through anonymous donor conception, we explore how lesbian parents experience communication about the donor conception within the family. While for these families "disclosure" of donor conception is often seen as evident, the way parents and children discuss this subject and how this is experienced by the parents themselves has not received much research attention. To meet this gap in the literature, in-depth interviews with lesbian couples were conducted. An Interpretative Phenomenological Analysis showed that this family communication process can be understood within the broader relational context of parent-child relationships. Even though parents handled this family communication in many different ways, these were all inspired by the same motives: acting in the child's best interest and-on a more implicit level-maintaining good relations within the family. Furthermore, parents left the initiative for talking about the DC mostly to the child. Overall, parents aimed at constructing a donor conception narrative that they considered acceptable for both the children and themselves. They used different strategies, such as gradual disclosure, limiting the meaning of the donor, and justifying the donor conception. Building an acceptable donor conception narrative was sometimes challenged by influences from the social environment. In the discussion, we relate this qualitative systemic study to the broader issues of selective disclosure and bidirectionality within families. © 2014 Family Process Institute.

  10. Whole blood donor deferral analysis at a center in Western India

    Directory of Open Access Journals (Sweden)

    Agnihotri Naveen

    2010-01-01

    Full Text Available Introduction: Deferrals lead to loss of precious whole blood donors (WBD and blood units available for transfusion purposes. Knowledge of rate and causes of donor deferral can guide the recruitment strategy for WBD. Aim: To find the incidence and causes of deferral in Indian WBD and apply relevant findings to modify recruitment strategy for blood donors. Materials and Methods: Data for WBD presenting for donation in a blood center and outdoor camps over one and half year were analyzed retrospectively. National guidelines were used for selection and deferral of WBD. Result: 736 (11.6% WBD were deferred out of 6357 presenting for donation during the study period. Most (69.8% of the donors were deferred on physical examination and hemoglobin (Hb testing. Most common reasons for deferral were low Hb (55.8%, abnormal blood pressure (11.1%, medication (6.9% and underweight donors (2.9%. Significantly more volunteers were deferred than relative donors (13.97% vs 5.80%; P<0.000. Females were found to have higher deferral rate than males (53.5% vs 6.9%; P=0.000 and higher odds ratio for deferral (15.4. Donors older than 40 years of age had significantly higher chance of being deferred (P<0.05. Discussion and Conclusion: It is important to determine the rate and causes of WBD deferral to guide the recruitment and retention efforts at local, regional, and national level.

  11. Responses to recipient and donor B cells by genetically donor T cells from human haploidentical chimeras

    International Nuclear Information System (INIS)

    Schiff, S.; Sampson, H.; Buckley, R.

    1986-01-01

    Following administration of haploidentical stem cells to infants with severe combined immunodeficiency (SCID), mature T cells of donor karyotype appear later in the recipient without causing graft-versus-host disease. To investigate the effect of the host environment on the responsiveness of these genetically donor T cells, blood B and T lymphocytes from 6 SCID recipients, their parental donors and unrelated controls were purified by double SRBC rosetting. T cells were stimulated by irradiated B cells at a 1:1 ratio in 6 day cultures. Engrafted T cells of donor karyotype gave much smaller responses to irradiated genetically recipient B cells than did fresh donor T cells. Moreover, engrafted T cells of donor karyotype from two of the three SCIDs who are longest post-transplantation responded more vigorously (14,685 and 31,623 cpm) than fresh donor T cells (5141 and 22,709 cpm) to donor B cells. These data indicate that T lymphocytes which have matured from donor stem cells in the recipient microenvironment behave differently from those that have matured in the donor

  12. The affinity plutonium(IV) for nitrogen donor ligands

    International Nuclear Information System (INIS)

    Jarvis, N.V.; Hancock, R.D.

    1994-01-01

    Established ligand design principles are used to predict the solution chemistry of Pu(IV) with nitrogen donor ligands which do not contain carboxylate donors. pK a 's of the nitrogen donors are lowered by addition of hydroxyalkyl groups causing Pu(IV) to have a greater affinity for these ligands than for hydroxide. Potentiometric studies using the ligands N,N,N'N',N''-pentakis(2-hydroxypropyl)-1,4,7-triazaheptane; N,N,N',N',N''-pentakis(2-hydroxyethyl)-1,4,7-triazaheptane; N,N,N',N',N'-tetrakis(2-hydroxyethyl)-1,2-diaminoethane; N,N,N',N'-tetrakis(2-hydroxyethyl)-trans-1,2-diaminocyclohexane; 1,4,8,11-tetrakis(2-hydroxyethyl)-1,4,8,11-tetraazacyclotetradecane and N,N-bis(2-hydroxyethyl)glycine with Pu(IV) showed that Pu(IV) has a considerable aqueous solution chemistry with these ligands. Data were processed by the ESTA library of programs and stability constants for all the systems are reported. Implications for selective ligand design for Pu(IV) are discussed. (orig.)

  13. Multi-Objective Particle Swarm Optimization Approach for Cost-Based Feature Selection in Classification.

    Science.gov (United States)

    Zhang, Yong; Gong, Dun-Wei; Cheng, Jian

    2017-01-01

    Feature selection is an important data-preprocessing technique in classification problems such as bioinformatics and signal processing. Generally, there are some situations where a user is interested in not only maximizing the classification performance but also minimizing the cost that may be associated with features. This kind of problem is called cost-based feature selection. However, most existing feature selection approaches treat this task as a single-objective optimization problem. This paper presents the first study of multi-objective particle swarm optimization (PSO) for cost-based feature selection problems. The task of this paper is to generate a Pareto front of nondominated solutions, that is, feature subsets, to meet different requirements of decision-makers in real-world applications. In order to enhance the search capability of the proposed algorithm, a probability-based encoding technology and an effective hybrid operator, together with the ideas of the crowding distance, the external archive, and the Pareto domination relationship, are applied to PSO. The proposed PSO-based multi-objective feature selection algorithm is compared with several multi-objective feature selection algorithms on five benchmark datasets. Experimental results show that the proposed algorithm can automatically evolve a set of nondominated solutions, and it is a highly competitive feature selection method for solving cost-based feature selection problems.

  14. Promoting Organ Donor Registries Through Public Education: What Is the Cost of Securing Organ Donors?

    Science.gov (United States)

    Razdan, Manik; Smith, Kenneth J; Bryce, Cindy L; Degenholtz, Howard B

    2016-06-01

    Transplant medicine's impact on America's public health is seriously limited by acute shortage of transplantable organs. Consequently, the United Sates has witnessed considerable investment in the promotion of organ donor registries. Although there is no evidence to support that donor registry promotion alleviates organ shortage, this belief continues to drive investments into registry promotion. In this study, return on investment in donor registry promotion was examined using cost-outcomes analysis. Cost of promoting the donor registry was estimated in US dollars whereas the outcome was measured as the number of individuals who join the registry (registrants) and their value in terms of organ donors. The study was conducted from the perspective of a regional Organ Procurement Organization (OPO). Costs were directly obtained from the OPO. The number of new registrants was obtained from the OPO and the departments of motor vehicles that maintain the donor registry. The value of registrants in terms of organ donors was computed based on a registrant's age-dependent risk of dying and age-dependent probability of becoming an organ donor. Six thousand seven hundred eight individuals joined the organ donor registry (95% confidence interval [95% CI], 5429-7956) at a cost of $455 per registrant (95% CI, US $383-US $562). These individuals result in 4.2 present-day donors (95% CI, 2.5-6.6) at a cost of US $726 000 (95% CI, US $462000-US $1.2 million). Because the cost per registrant and cost per donor is less than society's willingness to pay, donor registry promotion offers positive return on investment. Investment in registry promotion should at the minimum be maintained at current levels.

  15. Autotransplantation of Premolars With a 3-Dimensional Printed Titanium Replica of the Donor Tooth Functioning as a Surgical Guide: Proof of Concept.

    Science.gov (United States)

    Verweij, Jop P; Moin, David Anssari; Mensink, Gertjan; Nijkamp, Peter; Wismeijer, Daniel; van Merkesteyn, J P Richard

    2016-06-01

    Autotransplantation of premolars is a good treatment option for young patients who have missing teeth. This study evaluated the use of a preoperatively 3-dimensional (3D)-printed replica of the donor tooth that functions as a surgical guide during autotransplantation. Five consecutive procedures were prospectively observed. Transplantations of maxillary premolars with optimal root development were included in this study. A 3D-printed replica of the donor tooth was used to prepare a precisely fitting new alveolus at the recipient site before extracting the donor tooth. Procedure time, extra-alveolar time, and number of attempts needed to achieve a good fit of the donor tooth in the new alveolus were recorded. For each transplantation procedure, the surgical time was shorter than 30 minutes. An immediate good fit of the donor tooth in the new alveolus was achieved with an extra-alveolar time shorter than 1 minute for all transplantations. These results show that the extra-alveolar time is very short when the surgical guide is used; therefore, the chance of iatrogenic damage to the donor tooth is minimized. The use of a replica of the donor tooth makes the autotransplantation procedure easier for the surgeon and facilitates optimal placement of the transplant. Copyright © 2016 The American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  16. Gradient ascent pulse engineering approach to CNOT gates in donor electron spin quantum computing

    International Nuclear Information System (INIS)

    Tsai, D.-B.; Goan, H.-S.

    2008-01-01

    In this paper, we demonstrate how gradient ascent pulse engineering (GRAPE) optimal control methods can be implemented on donor electron spin qubits in semiconductors with an architecture complementary to the original Kane's proposal. We focus on the high fidelity controlled-NOT (CNOT) gate and we explicitly find the digitized control sequences for a controlled-NOT gate by optimizing its fidelity using the effective, reduced donor electron spin Hamiltonian with external controls over the hyperfine A and exchange J interactions. We then simulate the CNOT-gate sequence with the full spin Hamiltonian and find that it has an error of 10 -6 that is below the error threshold of 10 -4 required for fault-tolerant quantum computation. Also the CNOT gate operation time of 100 ns is 3 times faster than 297 ns of the proposed global control scheme.

  17. Optimal Selection of the Sampling Interval for Estimation of Modal Parameters by an ARMA- Model

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning

    1993-01-01

    Optimal selection of the sampling interval for estimation of the modal parameters by an ARMA-model for a white noise loaded structure modelled as a single degree of- freedom linear mechanical system is considered. An analytical solution for an optimal uniform sampling interval, which is optimal...

  18. CMV Serostatus of Donor-Recipient Pairs Influences the Risk of CMV Infection/Reactivation in HSCT Patients

    Directory of Open Access Journals (Sweden)

    Emilia Jaskula

    2012-01-01

    Full Text Available CMV donor/recipient serostatus was analyzed in 200 patients allografted in our institution from unrelated (122 patients donors and 78 sibling donors in the years 2002–2011 in relation to posttransplant complications. On a group basis independently of the CMV serostatus of donor-recipient pairs sibling transplantations and those from unrelated donors that matched 10/10 at allele level had a similar rate of CMV reactivation (17/78 versus 19/71, P=ns. The rate of CMV reactivation/infection was higher in patients grafted from donors accepted at the lower level of matching than 10/10 (18/38 versus 36/149, P=0.008. The incidence of aGvHD followed frequencies of CMV reactivation in the tested groups, being 40/156 and 25/44 in patients grafted from sibling or unrelated donors that 10/10 matched and in those grafted from donors taht HLA mismatched, respectively (P=0.001. Regarding the rate of reactivation in both groups seropositive patients receiving a transplant from seronegative donors had more frequently CMV reactivation as compared to those with another donor-recipient matching CMV serostatus constellation (22/43 versus 32/143, P=0<0.001. Multivariate analysis revealed that seropositivity of recipients with concomitant seronegativity of donors plays an independent role in the CMV reactivation/infection (OR=2.669, P=0.037; OR=5.322, P=0.078; OR=23.034, P=0.023 for optimally matched and mismatched patients and the whole group of patients, resp..

  19. [Survey of blood donors on the topic of "reimbursement for blood donors"].

    Science.gov (United States)

    Zeiler, T; Kretschmer, V

    1995-02-01

    Remuneration for blood donors, in the way as presently handled by governmental and communal blood transfusion services in Germany, is not generally accepted. It is feared that donors are recruited with increased risk to transmit infectious diseases, especially AIDS. Alternative incentives are discussed. After the so-called AIDS scandal in Germany, a change in the donor motivation was to be expected, associated with an increased willingness to renounce remuneration. Therefore, we performed the present survey, in which we evaluated the donor's willingness to renounce remuneration, possibilities of cashless remuneration and other alternative incentives. During March and April 1994, a total of 1,157 blood donors of the University Blood Bank Marburg were questioned anonymously by a questionnaire in the framework of whole-blood donations. Beside the above-mentioned aspects demoscopic data were included (age, sex, profession, journey). Cutting of remuneration without any other compensation was refused by 86.1% of the donors, 77% would not want to further donate blood in this case. Transfer of money to a bank account instead of cash payment was accepted by 78.6%, the use of non-negotiable cheques by 68.7%. Alternative compensation by tickets for theater, concert, cinema or coupons for restaurants met with the approval of only 27.3%; under these circumstances, 36.9% would be willing to continue blood donation. With increasing age and number of donations, but largely independent of social status, donors attached greater importance to retention of remuneration. Cutting of remuneration would result in a considerable reduction of the willingness to donate blood within the population of donors of the governmental and communal blood transfusion services. However, an increase of virus safety of the blood products would not be reached in this way, since especially the long-term donors would be driven away. Considerable bottlenecks, particularly in the specific blood supply of

  20. Blood group genotyping: from patient to high-throughput donor screening.

    Science.gov (United States)

    Veldhuisen, B; van der Schoot, C E; de Haas, M

    2009-10-01

    Blood group antigens, present on the cell membrane of red blood cells and platelets, can be defined either serologically or predicted based on the genotypes of genes encoding for blood group antigens. At present, the molecular basis of many antigens of the 30 blood group systems and 17 human platelet antigens is known. In many laboratories, blood group genotyping assays are routinely used for diagnostics in cases where patient red cells cannot be used for serological typing due to the presence of auto-antibodies or after recent transfusions. In addition, DNA genotyping is used to support (un)-expected serological findings. Fetal genotyping is routinely performed when there is a risk of alloimmune-mediated red cell or platelet destruction. In case of patient blood group antigen typing, it is important that a genotyping result is quickly available to support the selection of donor blood, and high-throughput of the genotyping method is not a prerequisite. In addition, genotyping of blood donors will be extremely useful to obtain donor blood with rare phenotypes, for example lacking a high-frequency antigen, and to obtain a fully typed donor database to be used for a better matching between recipient and donor to prevent adverse transfusion reactions. Serological typing of large cohorts of donors is a labour-intensive and expensive exercise and hampered by the lack of sufficient amounts of approved typing reagents for all blood group systems of interest. Currently, high-throughput genotyping based on DNA micro-arrays is a very feasible method to obtain a large pool of well-typed blood donors. Several systems for high-throughput blood group genotyping are developed and will be discussed in this review.

  1. The impact of meeting donor management goals on the number of organs transplanted per donor: results from the United Network for Organ Sharing Region 5 prospective donor management goals study.

    Science.gov (United States)

    Malinoski, Darren J; Patel, Madhukar S; Daly, Michael C; Oley-Graybill, Chrystal; Salim, Ali

    2012-10-01

    Many organ procurement organizations have implemented critical care end points as donor management goals in efforts to increase organs transplanted per donor after neurologic determination of death. Although retrospective studies have demonstrated an association between meeting donor management goals and organ yield, prospective studies are lacking. In June 2008, nine donor management goals were prospectively implemented as a checklist and every donor after neurologic determination of death was managed to meet them. The donor management goals represented normal cardiovascular, pulmonary, renal, and endocrine end points. Data were collected for 7 months. Donor management goals "met" was defined a priori as achieving any seven of the nine donor management goals, and this was recorded at the time of consent, 12-18 hrs later, and prior to organ recovery. The primary outcome measure was ≥4 organs transplanted per donor, and binary logistic regression was used to identify independent predictors of this outcome with a porgan procurement organizations in the five Southwestern United States (United Network for Organ Sharing Region 5). All standard criteria donors after neurologic determination of deaths. Prospective implementation of a donor management goal checklist. There were 380 standard criteria donors with 3.6±1.7 organs transplanted per donor. Fifteen percent had donor management goals met at the time of consent, 33% at 12-18 hrs, and 38% prior to organ recovery. Forty-eight percent had ≥4 organs transplanted per donor. Donors with ≥4 organs transplanted per donor had significantly more individual donor management goals met at all three time points. Independent predictors of ≥4 organs transplanted per donor were age (odds ratio=0.95 per year), final creatinine (odds ratio=0.75 per 1-unit increase), donor management goals "met" at consent (odds ratio=2.03), donor management goals "met" prior to organ recovery (odds ratio=2.34), and a change in the number of

  2. A new and fast image feature selection method for developing an optimal mammographic mass detection scheme.

    Science.gov (United States)

    Tan, Maxine; Pu, Jiantao; Zheng, Bin

    2014-08-01

    Selecting optimal features from a large image feature pool remains a major challenge in developing computer-aided detection (CAD) schemes of medical images. The objective of this study is to investigate a new approach to significantly improve efficacy of image feature selection and classifier optimization in developing a CAD scheme of mammographic masses. An image dataset including 1600 regions of interest (ROIs) in which 800 are positive (depicting malignant masses) and 800 are negative (depicting CAD-generated false positive regions) was used in this study. After segmentation of each suspicious lesion by a multilayer topographic region growth algorithm, 271 features were computed in different feature categories including shape, texture, contrast, isodensity, spiculation, local topological features, as well as the features related to the presence and location of fat and calcifications. Besides computing features from the original images, the authors also computed new texture features from the dilated lesion segments. In order to select optimal features from this initial feature pool and build a highly performing classifier, the authors examined and compared four feature selection methods to optimize an artificial neural network (ANN) based classifier, namely: (1) Phased Searching with NEAT in a Time-Scaled Framework, (2) A sequential floating forward selection (SFFS) method, (3) A genetic algorithm (GA), and (4) A sequential forward selection (SFS) method. Performances of the four approaches were assessed using a tenfold cross validation method. Among these four methods, SFFS has highest efficacy, which takes 3%-5% of computational time as compared to GA approach, and yields the highest performance level with the area under a receiver operating characteristic curve (AUC) = 0.864 ± 0.034. The results also demonstrated that except using GA, including the new texture features computed from the dilated mass segments improved the AUC results of the ANNs optimized

  3. Optimal foraging in marine ecosystem models: selectivity, profitability and switching

    DEFF Research Database (Denmark)

    Visser, Andre W.; Fiksen, Ø.

    2013-01-01

    ecological mechanics and evolutionary logic as a solution to diet selection in ecosystem models. When a predator can consume a range of prey items it has to choose which foraging mode to use, which prey to ignore and which ones to pursue, and animals are known to be particularly skilled in adapting...... to the preference functions commonly used in models today. Indeed, depending on prey class resolution, optimal foraging can yield feeding rates that are considerably different from the ‘switching functions’ often applied in marine ecosystem models. Dietary inclusion is dictated by two optimality choices: 1...... by letting predators maximize energy intake or more properly, some measure of fitness where predation risk and cost are also included. An optimal foraging or fitness maximizing approach will give marine ecosystem models a sound principle to determine trophic interactions...

  4. Selection of the optimal Box-Cox transformation parameter for modelling and forecasting age-specific fertility

    OpenAIRE

    Shang, Han Lin

    2015-01-01

    The Box-Cox transformation can sometimes yield noticeable improvements in model simplicity, variance homogeneity and precision of estimation, such as in modelling and forecasting age-specific fertility. Despite its importance, there have been few studies focusing on the optimal selection of Box-Cox transformation parameters in demographic forecasting. A simple method is proposed for selecting the optimal Box-Cox transformation parameter, along with an algorithm based on an in-sample forecast ...

  5. Donor exosomes rather than passenger leukocytes initiate alloreactive T cell responses after transplantation

    Science.gov (United States)

    Marino, Jose; Babiker-Mohamed, Mohamed H.; Crosby-Bertorini, Patrick; Paster, Joshua T.; LeGuern, Christian; Germana, Sharon; Abdi, Reza; Uehara, Mayuko; Kim, James I.; Markmann, James F.; Tocco, Georges; Benichou, Gilles

    2016-01-01

    Transplantation of allogeneic organs and tissues represents a lifesaving procedure for a variety of patients affected with end-stage diseases. Although current immunosuppressive therapy prevents early acute rejection, it is associated with nephrotoxicity and increased risks for infection and neoplasia. This stresses the need for selective immune-based therapies relying on manipulation of lymphocyte recognition of donor antigens. The passenger leukocyte theory states that allograft rejection is initiated by recipient T cells recognizing donor major histocompatibility complex (MHC) molecules displayed on graft leukocytes migrating to the host’s lymphoid organs. We revisited this concept in mice transplanted with allogeneic skin, heart, or islet grafts using imaging flow cytometry. We observed no donor cells in the lymph nodes and spleen of skin-grafted mice, but we found high numbers of recipient cells displaying allogeneic MHC molecules (cross-dressed) acquired from donor microvesicles (exosomes). After heart or islet transplantation, we observed few donor leukocytes (100 per million) but large numbers of recipient cells cross-dressed with donor MHC (>90,000 per million). Last, we showed that purified allogeneic exosomes induced proinflammatory alloimmune responses by T cells in vitro and in vivo. Collectively, these results suggest that recipient antigen-presenting cells cross-dressed with donor MHC rather than passenger leukocytes trigger T cell responses after allotransplantation. PMID:27942611

  6. Fullerene C70 as a p-type donor in organic photovoltaic cells

    International Nuclear Information System (INIS)

    Zhuang, Taojun; Wang, Xiao-Feng; Sano, Takeshi; Kido, Junji; Hong, Ziruo; Li, Gang; Yang, Yang

    2014-01-01

    Fullerenes and their derivatives have been widely used as n-type materials in organic transistor and photovoltaic devices. Though it is believed that they shall be ambipolar in nature, there have been few direct experimental proofs for that. In this work, fullerene C 70 , known as an efficient acceptor, has been employed as a p-type electron donor in conjunction with 1,4,5,8,9,11-hexaazatriphenylene hexacarbonitrile as an electron acceptor in planar-heterojunction (PHJ) organic photovoltaic (OPV) cells. High fill factors (FFs) of more than 0.70 were reliably achieved with the C 70 layer even up to 100 nm thick in PHJ cells, suggesting the superior potential of fullerene C 70 as the p-type donor in comparison to other conventional donor materials. The optimal efficiency of these unconventional PHJ cells was 2.83% with a short-circuit current of 5.33 mA/cm 2 , an open circuit voltage of 0.72 V, and a FF of 0.74. The results in this work unveil the potential of fullerene materials as donors in OPV devices, and provide alternative approaches towards future OPV applications.

  7. Effects of pasteurization on adiponectin and insulin concentrations in donor human milk.

    Science.gov (United States)

    Ley, Sylvia H; Hanley, Anthony J; Stone, Debbie; O'Connor, Deborah L

    2011-09-01

    Although pasteurization is recommended before distributing donor human milk in North America, limited data are available on its impact on metabolic hormones in milk. We aimed to investigate the effects of pasteurization on adiponectin and insulin concentrations in donor human milk. The study investigates concentrations of components in donor human milk before and after Holder pasteurization. After the guidelines of the Human Milk Bank Association of North America, human milk samples were pooled to produce 17 distinct batches (4 individuals per batch) and pasteurized at 62.5°C for 30 min. Adiponectin, insulin, energy, fat, total protein, and glucose concentrations were measured pre- and postpasteurization. Pasteurization reduced milk adiponectin and insulin by 32.8 and 46.1%, respectively (both p Pasteurization effects on milk hormone concentrations remained significant after adjusting for fat and energy (beta ± SEE: -4.11 ± 1.27, p = 0.003 for adiponectin; -70.0 ± 15.0, p pasteurization reduced adiponectin and insulin concentrations in donor human milk. In view of emerging knowledge on the importance of milk components, continued work to find the optimal pasteurization process that mitigates risks but promotes retention of bioactive components is needed.

  8. Human decellularized bone scaffolds from aged donors show improved osteoinductive capacity compared to young donor bone.

    Directory of Open Access Journals (Sweden)

    Christopher A Smith

    Full Text Available To improve the safe use of allograft bone, decellularization techniques may be utilized to produce acellular scaffolds. Such scaffolds should retain their innate biological and biomechanical capacity and support mesenchymal stem cell (MSC osteogenic differentiation. However, as allograft bone is derived from a wide age-range, this study aimed to determine whether donor age impacts on the ability an osteoinductive, acellular scaffold produced from human bone to promote the osteogenic differentiation of bone marrow MSCs (BM-MSC. BM-MSCs from young and old donors were seeded on acellular bone cubes from young and old donors undergoing osteoarthritis related hip surgery. All combinations resulted in increased osteogenic gene expression, and alkaline phosphatase (ALP enzyme activity, however BM-MSCs cultured on old donor bone displayed the largest increases. BM-MSCs cultured in old donor bone conditioned media also displayed higher osteogenic gene expression and ALP activity than those exposed to young donor bone conditioned media. ELISA and Luminex analysis of conditioned media demonstrated similar levels of bioactive factors between age groups; however, IGF binding protein 1 (IGFBP1 concentration was significantly higher in young donor samples. Additionally, structural analysis of old donor bone indicated an increased porosity compared to young donor bone. These results demonstrate the ability of a decellularized scaffold produced from young and old donors to support osteogenic differentiation of cells from young and old donors. Significantly, the older donor bone produced greater osteogenic differentiation which may be related to reduced IGFBP1 bioavailability and increased porosity, potentially explaining the excellent clinical results seen with the use of allograft from aged donors.

  9. Optimal and Suboptimal Finger Selection Algorithms for MMSE Rake Receivers in Impulse Radio Ultra-Wideband Systems

    Directory of Open Access Journals (Sweden)

    Chiang Mung

    2006-01-01

    Full Text Available The problem of choosing the optimal multipath components to be employed at a minimum mean square error (MMSE selective Rake receiver is considered for an impulse radio ultra-wideband system. First, the optimal finger selection problem is formulated as an integer programming problem with a nonconvex objective function. Then, the objective function is approximated by a convex function and the integer programming problem is solved by means of constraint relaxation techniques. The proposed algorithms are suboptimal due to the approximate objective function and the constraint relaxation steps. However, they perform better than the conventional finger selection algorithm, which is suboptimal since it ignores the correlation between multipath components, and they can get quite close to the optimal scheme that cannot be implemented in practice due to its complexity. In addition to the convex relaxation techniques, a genetic-algorithm- (GA- based approach is proposed, which does not need any approximations or integer relaxations. This iterative algorithm is based on the direct evaluation of the objective function, and can achieve near-optimal performance with a reasonable number of iterations. Simulation results are presented to compare the performance of the proposed finger selection algorithms with that of the conventional and the optimal schemes.

  10. Artificial Intelligence Based Selection of Optimal Cutting Tool and Process Parameters for Effective Turning and Milling Operations

    Science.gov (United States)

    Saranya, Kunaparaju; John Rozario Jegaraj, J.; Ramesh Kumar, Katta; Venkateshwara Rao, Ghanta

    2016-06-01

    With the increased trend in automation of modern manufacturing industry, the human intervention in routine, repetitive and data specific activities of manufacturing is greatly reduced. In this paper, an attempt has been made to reduce the human intervention in selection of optimal cutting tool and process parameters for metal cutting applications, using Artificial Intelligence techniques. Generally, the selection of appropriate cutting tool and parameters in metal cutting is carried out by experienced technician/cutting tool expert based on his knowledge base or extensive search from huge cutting tool database. The present proposed approach replaces the existing practice of physical search for tools from the databooks/tool catalogues with intelligent knowledge-based selection system. This system employs artificial intelligence based techniques such as artificial neural networks, fuzzy logic and genetic algorithm for decision making and optimization. This intelligence based optimal tool selection strategy is developed using Mathworks Matlab Version 7.11.0 and implemented. The cutting tool database was obtained from the tool catalogues of different tool manufacturers. This paper discusses in detail, the methodology and strategies employed for selection of appropriate cutting tool and optimization of process parameters based on multi-objective optimization criteria considering material removal rate, tool life and tool cost.

  11. Pareto Optimal Solutions for Network Defense Strategy Selection Simulator in Multi-Objective Reinforcement Learning

    Directory of Open Access Journals (Sweden)

    Yang Sun

    2018-01-01

    Full Text Available Using Pareto optimization in Multi-Objective Reinforcement Learning (MORL leads to better learning results for network defense games. This is particularly useful for network security agents, who must often balance several goals when choosing what action to take in defense of a network. If the defender knows his preferred reward distribution, the advantages of Pareto optimization can be retained by using a scalarization algorithm prior to the implementation of the MORL. In this paper, we simulate a network defense scenario by creating a multi-objective zero-sum game and using Pareto optimization and MORL to determine optimal solutions and compare those solutions to different scalarization approaches. We build a Pareto Defense Strategy Selection Simulator (PDSSS system for assisting network administrators on decision-making, specifically, on defense strategy selection, and the experiment results show that the Satisficing Trade-Off Method (STOM scalarization approach performs better than linear scalarization or GUESS method. The results of this paper can aid network security agents attempting to find an optimal defense policy for network security games.

  12. Optimal design and selection of magneto-rheological brake types based on braking torque and mass

    International Nuclear Information System (INIS)

    Nguyen, Q H; Lang, V T; Choi, S B

    2015-01-01

    In developing magnetorheological brakes (MRBs), it is well known that the braking torque and the mass of the MRBs are important factors that should be considered in the product’s design. This research focuses on the optimal design of different types of MRBs, from which we identify an optimal selection of MRB types, considering braking torque and mass. In the optimization, common types of MRBs such as disc-type, drum-type, hybrid-type, and T-shape types are considered. The optimization problem is to find an optimal MRB structure that can produce the required braking torque while minimizing its mass. After a brief description of the configuration of the MRBs, the MRBs’ braking torque is derived based on the Herschel-Bulkley rheological model of the magnetorheological fluid. Then, the optimal designs of the MRBs are analyzed. The optimization objective is to minimize the mass of the brake while the braking torque is constrained to be greater than a required value. In addition, the power consumption of the MRBs is also considered as a reference parameter in the optimization. A finite element analysis integrated with an optimization tool is used to obtain optimal solutions for the MRBs. Optimal solutions of MRBs with different required braking torque values are obtained based on the proposed optimization procedure. From the results, we discuss the optimal selection of MRB types, considering braking torque and mass. (technical note)

  13. Glucosamine derived DISAL donors for stereoselective glycosylations under neutral conditions

    DEFF Research Database (Denmark)

    Grathe, S.; Thygesen, M.B.; Larsen, K.

    2005-01-01

    DISAL (methyl 3,5-dinitrosa/icylate) D-glcosyl, D-galactosyl, D-mannosyl, and L-quinovosyl donors have previously provided the efficient glycosylation of a range of substrates under either strictly neutral, mildly basic, or very mildly Lewis acidic (LiClO4) conditions. Herein we report the synthe......DISAL (methyl 3,5-dinitrosa/icylate) D-glcosyl, D-galactosyl, D-mannosyl, and L-quinovosyl donors have previously provided the efficient glycosylation of a range of substrates under either strictly neutral, mildly basic, or very mildly Lewis acidic (LiClO4) conditions. Herein we report...... the synthesis of new glucosamine DISAL donors, carrying N-TCP, -Troc, or -TFAc protecting groups, and their use in beta-(1,2-trans) selective glycosylations, primarily in NMP in the absence of any added Lewis acids, or in CH3NO2 with LiClO4. Finally, precise microwave heating proved effective in promoting...

  14. Compliance with donor age recommendations in oocyte donor recruitment advertisements in the USA.

    Science.gov (United States)

    Alberta, Hillary B; Berry, Roberta M; Levine, Aaron D

    2013-04-01

    IVF using donated oocytes offers benefits to many infertile patients, yet the technique also raises a number of ethical concerns, including worries about potential physical and psychological risks to oocyte donors. In the USA, oversight of oocyte donation consists of a combination of federal and state regulations and self-regulatory guidelines promulgated by the American Society for Reproductive Medicine. This study assesses compliance with one of these self-regulatory guidelines - specifically, ASRM's preferred minimum age for donors of 21. To assess compliance, 539 oocyte donor recruitment advertisements from two recruitment channels (Craigslist and college newspapers) were collected and evaluated. Of these, 61% in the Craigslist dataset and 43% in the college newspaper dataset listed minimum ages between 18 and 20, which is inconsistent with ASRM's preferred minimum age recommendation of 21. Advertisements placed by oocyte donor recruitment agencies were more likely than advertisements placed by clinics to specify minimum ages between 18 and 20. These results indicate that ASRM should evaluate and consider revising its donor age guidelines. IVF using donated human eggs can help many patients who have difficulty having children. However, the technique also raises ethical concerns, including concerns about potential physical and psychological harms to egg donors. In the USA, oversight of egg donation relies on a combination of federal and state regulation and professional self-regulation. Governmental regulations address only limited aspects of egg donation, such as the potential spread of infectious diseases and the reporting of success rates, leaving voluntary guidelines developed by an association of medical professionals to address most issues, including ethical concerns raised by the practice. One of these voluntary guidelines recommends that egg donors should be at least 21 years of age. In this article, we analysed 539 egg donor recruitment advertisements

  15. Development of Organ-Specific Donor Risk Indices

    OpenAIRE

    Akkina, Sanjeev K.; Asrani, Sumeet K.; Peng, Yi; Stock, Peter; Kim, Ray; Israni, Ajay K.

    2012-01-01

    Due to the shortage of deceased donor organs, transplant centers accept organs from marginal deceased donors, including older donors. Organ-specific donor risk indices have been developed to predict graft survival using various combinations of donor and recipient characteristics. We will review the kidney donor risk index (KDRI) and liver donor risk index (LDRI) and compare and contrast their strengths, limitations, and potential uses. The Kidney Donor Risk Index has a potential role in devel...

  16. Iron deficiency among blood donors

    DEFF Research Database (Denmark)

    Rigas, A S; Pedersen, O B; Magnussen, K

    2017-01-01

    Blood components collected from blood donors are an invaluable part of modern-day medicine. A healthy blood donor population is therefore of paramount importance. The results from the Danish Blood Donor Study (DBDS) indicate that gender, number of previous donations, time since last donation...... and menopausal status are the strongest predictors of iron deficiency. Only little information on the health effects of iron deficiency in blood donors exits. Possibly, after a standard full blood donation, a temporarily reduced physical performance for women is observed. However, iron deficiency among blood...... donors is not reflected in a reduced self-perceived mental and physical health. In general, the high proportion of iron-deficient donors can be alleviated either by extending the inter-donation intervals or by guided iron supplementation. The experience from Copenhagen, the Capital Region of Denmark...

  17. Unrelated Hematopoietic Stem Cell Donor Matching Probability and Search Algorithm

    Directory of Open Access Journals (Sweden)

    J.-M. Tiercy

    2012-01-01

    Full Text Available In transplantation of hematopoietic stem cells (HSCs from unrelated donors a high HLA compatibility level decreases the risk of acute graft-versus-host disease and mortality. The diversity of the HLA system at the allelic and haplotypic level and the heterogeneity of HLA typing data of the registered donors render the search process a complex task. This paper summarizes our experience with a search algorithm that includes at the start of the search a probability estimate (high/intermediate/low to identify a HLA-A, B, C, DRB1, DQB1-compatible donor (a 10/10 match. Based on 2002–2011 searches about 30% of patients have a high, 30% an intermediate, and 40% a low probability search. Search success rate and duration are presented and discussed in light of the experience of other centers. Overall a 9-10/10 matched HSC donor can now be identified for 60–80% of patients of European descent. For high probability searches donors can be selected on the basis of DPB1-matching with an estimated success rate of >40%. For low probability searches there is no consensus on which HLA incompatibilities are more permissive, although HLA-DQB1 mismatches are generally considered as acceptable. Models for the discrimination of more detrimental mismatches based on specific amino acid residues rather than specific HLA alleles are presented.

  18. Suicidal hanging donors for lung transplantation

    Science.gov (United States)

    Ananiadou, Olga; Schmack, Bastian; Zych, Bartlomiej; Sabashnikov, Anton; Garcia-Saez, Diana; Mohite, Prashant; Weymann, Alexander; Mansur, Ashham; Zeriouh, Mohamed; Marczin, Nandor; De Robertis, Fabio; Simon, Andre Rüdiger; Popov, Aron-Frederik

    2018-01-01

    Abstract In the context of limited donor pool in cardiothoracic transplantation, utilization of organs from high risk donors, such as suicidal hanging donors, while ensuring safety, is under consideration. We sought to evaluate the outcomes of lung transplantations (LTx) that use organs from this group. Between January 2011 and December 2015, 265 LTx were performed at our center. Twenty-two recipients received lungs from donors after suicidal hanging (group 1). The remaining 243 transplantations were used as a control (group 2). Analysis of recipient and donor characteristics as well as outcomes was performed. No statistically significant difference was found in the donor characteristics between analyzed groups, except for higher incidence of cardiac arrest, younger age and smoking history of hanging donors (P donor cause of death is not associated with poor mid-term survival or chronic lung allograft dysfunction following transplantation. These results encourage assessment of lungs from hanging donors, and their consideration for transplantation. PMID:29620623

  19. Cancer Feature Selection and Classification Using a Binary Quantum-Behaved Particle Swarm Optimization and Support Vector Machine

    Directory of Open Access Journals (Sweden)

    Maolong Xi

    2016-01-01

    Full Text Available This paper focuses on the feature gene selection for cancer classification, which employs an optimization algorithm to select a subset of the genes. We propose a binary quantum-behaved particle swarm optimization (BQPSO for cancer feature gene selection, coupling support vector machine (SVM for cancer classification. First, the proposed BQPSO algorithm is described, which is a discretized version of original QPSO for binary 0-1 optimization problems. Then, we present the principle and procedure for cancer feature gene selection and cancer classification based on BQPSO and SVM with leave-one-out cross validation (LOOCV. Finally, the BQPSO coupling SVM (BQPSO/SVM, binary PSO coupling SVM (BPSO/SVM, and genetic algorithm coupling SVM (GA/SVM are tested for feature gene selection and cancer classification on five microarray data sets, namely, Leukemia, Prostate, Colon, Lung, and Lymphoma. The experimental results show that BQPSO/SVM has significant advantages in accuracy, robustness, and the number of feature genes selected compared with the other two algorithms.

  20. Cancer Feature Selection and Classification Using a Binary Quantum-Behaved Particle Swarm Optimization and Support Vector Machine

    Science.gov (United States)

    Sun, Jun; Liu, Li; Fan, Fangyun; Wu, Xiaojun

    2016-01-01

    This paper focuses on the feature gene selection for cancer classification, which employs an optimization algorithm to select a subset of the genes. We propose a binary quantum-behaved particle swarm optimization (BQPSO) for cancer feature gene selection, coupling support vector machine (SVM) for cancer classification. First, the proposed BQPSO algorithm is described, which is a discretized version of original QPSO for binary 0-1 optimization problems. Then, we present the principle and procedure for cancer feature gene selection and cancer classification based on BQPSO and SVM with leave-one-out cross validation (LOOCV). Finally, the BQPSO coupling SVM (BQPSO/SVM), binary PSO coupling SVM (BPSO/SVM), and genetic algorithm coupling SVM (GA/SVM) are tested for feature gene selection and cancer classification on five microarray data sets, namely, Leukemia, Prostate, Colon, Lung, and Lymphoma. The experimental results show that BQPSO/SVM has significant advantages in accuracy, robustness, and the number of feature genes selected compared with the other two algorithms. PMID:27642363

  1. Iron concentrations in breast milk and selected maternal factors of human milk bank donors.

    Science.gov (United States)

    Mello-Neto, Julio; Rondó, Patrícia H C; Morgano, Marcelo A; Oshiiwa, Marie; Santos, Mariana L; Oliveira, Julicristie M

    2010-05-01

    The aim of this study was to evaluate the relationship between iron concentration in mature breast milk and characteristics of 136 donors of a Brazilian milk bank. Iron, vitamin A, zinc, and copper concentrations were assessed in human milk and maternal blood. Data were collected on maternal anthropometrics, obstetric, socioeconomic, demographic, and lifestyle factors. Iron, zinc, and copper in milk and zinc and copper in blood were detected by spectrophotometry. Vitamin A in milk and blood was determined by high-performance liquid chromatography. Hemoglobin was measured by electronic counting and serum iron and ferritin by colorimetry and chemoluminescence, respectively. Transferrin and ceruloplasmin were determined by nephelometry. According to multivariate linear regression analysis, iron in milk was positively associated with vitamin A in milk and with smoking but negatively associated with timing of breast milk donation (P milk of Brazilian donors may be influenced by nutritional factors and smoking.

  2. The cost-effectiveness of using payment to increase living donor kidneys for transplantation.

    Science.gov (United States)

    Barnieh, Lianne; Gill, John S; Klarenbach, Scott; Manns, Braden J

    2013-12-01

    For eligible candidates, transplantation is considered the optimal treatment compared with dialysis for patients with ESRD. The growing number of patients with ESRD requires new strategies to increase the pool of potential donors. Using decision analysis modeling, this study compared a strategy of paying living kidney donors to waitlisted recipients on dialysis with the current organ donation system. In the base case estimate, this study assumed that the number of donors would increase by 5% with a payment of $10,000. Quality of life estimates, resource use, and costs (2010 Canadian dollars) were based on the best available published data. Compared with the current organ donation system, a strategy of increasing the number of kidneys for transplantation by 5% by paying living donors $10,000 has an incremental cost-savings of $340 and a gain of 0.11 quality-adjusted life years. Increasing the number of kidneys for transplantation by 10% and 20% would translate into incremental cost-savings of $1640 and $4030 and incremental quality-adjusted life years gain of 0.21 and 0.39, respectively. Although the impact is uncertain, this model suggests that a strategy of paying living donors to increase the number of kidneys available for transplantation could be cost-effective, even with a transplant rate increase of only 5%. Future work needs to examine the feasibility, legal policy, ethics, and public perception of a strategy to pay living donors.

  3. Natural selection and optimality

    International Nuclear Information System (INIS)

    Torres, J.L.

    1989-01-01

    It is assumed that Darwin's principle translates into optimal regimes of operation along metabolical pathways in an ecological system. Fitness is then defined in terms of the distance of a given individual's thermodynamic parameters from their optimal values. The method is illustrated testing maximum power as a criterion of merit satisfied in ATP synthesis. (author). 26 refs, 2 figs

  4. Log-Optimal Portfolio Selection Using the Blackwell Approachability Theorem

    OpenAIRE

    V'yugin, Vladimir

    2014-01-01

    We present a method for constructing the log-optimal portfolio using the well-calibrated forecasts of market values. Dawid's notion of calibration and the Blackwell approachability theorem are used for computing well-calibrated forecasts. We select a portfolio using this "artificial" probability distribution of market values. Our portfolio performs asymptotically at least as well as any stationary portfolio that redistributes the investment at each round using a continuous function of side in...

  5. Q-FISH measurement of hepatocyte telomere lengths in donor liver and graft after pediatric living-donor liver transplantation: donor age affects telomere length sustainability.

    Directory of Open Access Journals (Sweden)

    Youichi Kawano

    Full Text Available Along with the increasing need for living-donor liver transplantation (LDLT, the issue of organ shortage has become a serious problem. Therefore, the use of organs from elderly donors has been increasing. While the short-term results of LDLT have greatly improved, problems affecting the long-term outcome of transplant patients remain unsolved. Furthermore, since contradictory data have been reported with regard to the relationship between donor age and LT/LDLT outcome, the question of whether the use of elderly donors influences the long-term outcome of a graft after LT/LDLT remains unsettled. To address whether hepatocyte telomere length reflects the outcome of LDLT, we analyzed the telomere lengths of hepatocytes in informative biopsy samples from 12 paired donors and recipients (grafts of pediatric LDLT more than 5 years after adult-to-child LDLT because of primary biliary atresia, using quantitative fluorescence in situ hybridization (Q-FISH. The telomere lengths in the paired samples showed a robust relationship between the donor and grafted hepatocytes (r = 0.765, p = 0.0038, demonstrating the feasibility of our Q-FISH method for cell-specific evaluation. While 8 pairs showed no significant difference between the telomere lengths for the donor and the recipient, the other 4 pairs showed significantly shorter telomeres in the recipient than in the donor. Multiple regression analysis revealed that the donors in the latter group were older than those in the former (p = 0.001. Despite the small number of subjects, this pilot study indicates that donor age is a crucial factor affecting telomere length sustainability in hepatocytes after pediatric LDLT, and that the telomeres in grafted livers may be elongated somewhat longer when the grafts are immunologically well controlled.

  6. Renal Transplantation from Elderly Living Donors

    Directory of Open Access Journals (Sweden)

    Jacob A. Akoh

    2013-01-01

    Full Text Available Acceptance of elderly living kidney donors remains controversial due to the higher incidence of comorbidity and greater risk of postoperative complications. This is a review of publications in the English language between 2000 and 2013 about renal transplantation from elderly living donors to determine trends and effects of donation, and the outcomes of such transplantation. The last decade witnessed a 50% increase in living kidney donor transplants, with a disproportionate increase in donors >60 years. There is no accelerated loss of kidney function following donation, and the incidence of established renal failure (ERF and hypertension among donors is similar to that of the general population. The overall incidence of ERF in living donors is about 0.134 per 1000 years. Elderly donors require rigorous assessment and should have a predicted glomerular filtration rate of at least 37.5 mL/min/1.73 m2 at the age of 80. Though elderly donors had lower glomerular filtration rate before donation, proportionate decline after donation was similar in both young and elderly groups. The risks of delayed graft function, acute rejection, and graft failure in transplants from living donors >65 years are significantly higher than transplants from younger donors. A multicentred, long-term, and prospective database addressing the outcomes of kidneys from elderly living donors is recommended.

  7. Working with previously anonymous gamete donors and donor-conceived adults: recent practice experiences of running the DNA-based voluntary information exchange and contact register, UK DonorLink.

    Science.gov (United States)

    Crawshaw, Marilyn; Gunter, Christine; Tidy, Christine; Atherton, Freda

    2013-03-01

    This article describes recent practice experiences with donor conceived adults, donors, non-donor-conceived adult children of donors using the voluntary DNA-based register, UK DonorLink. It highlights additional complexities faced when using DNA rather than paper records for searching, in particular from the risk of false positives, low chances of success and potential inclusion of biological parents' DNA. Professionals' experiences in supporting those being "linked" suggest challenges as well as rewards. Registration carries the potential to be therapeutic for donor-conceived adults and donors and to enhance their political awareness regardless of links being made. Registrants value both peer and professional support, providing the latter can respond flexibly and be delivered by staff experienced in intermediary work. Given that the majority of those affected by donor conception internationally come from anonymous donation systems, these findings are highly pertinent and argue the need for political and moral debate about such service provision.

  8. A particle swarm optimization algorithm for beam angle selection in intensity-modulated radiotherapy planning

    International Nuclear Information System (INIS)

    Li Yongjie; Yao Dezhong; Yao, Jonathan; Chen Wufan

    2005-01-01

    Automatic beam angle selection is an important but challenging problem for intensity-modulated radiation therapy (IMRT) planning. Though many efforts have been made, it is still not very satisfactory in clinical IMRT practice because of overextensive computation of the inverse problem. In this paper, a new technique named BASPSO (Beam Angle Selection with a Particle Swarm Optimization algorithm) is presented to improve the efficiency of the beam angle optimization problem. Originally developed as a tool for simulating social behaviour, the particle swarm optimization (PSO) algorithm is a relatively new population-based evolutionary optimization technique first introduced by Kennedy and Eberhart in 1995. In the proposed BASPSO, the beam angles are optimized using PSO by treating each beam configuration as a particle (individual), and the beam intensity maps for each beam configuration are optimized using the conjugate gradient (CG) algorithm. These two optimization processes are implemented iteratively. The performance of each individual is evaluated by a fitness value calculated with a physical objective function. A population of these individuals is evolved by cooperation and competition among the individuals themselves through generations. The optimization results of a simulated case with known optimal beam angles and two clinical cases (a prostate case and a head-and-neck case) show that PSO is valid and efficient and can speed up the beam angle optimization process. Furthermore, the performance comparisons based on the preliminary results indicate that, as a whole, the PSO-based algorithm seems to outperform, or at least compete with, the GA-based algorithm in computation time and robustness. In conclusion, the reported work suggested that the introduced PSO algorithm could act as a new promising solution to the beam angle optimization problem and potentially other optimization problems in IMRT, though further studies need to be investigated

  9. Parallel algorithms for islanded microgrid with photovoltaic and energy storage systems planning optimization problem: Material selection and quantity demand optimization

    Science.gov (United States)

    Cao, Yang; Liu, Chun; Huang, Yuehui; Wang, Tieqiang; Sun, Chenjun; Yuan, Yue; Zhang, Xinsong; Wu, Shuyun

    2017-02-01

    With the development of roof photovoltaic power (PV) generation technology and the increasingly urgent need to improve supply reliability levels in remote areas, islanded microgrid with photovoltaic and energy storage systems (IMPE) is developing rapidly. The high costs of photovoltaic panel material and energy storage battery material have become the primary factors that hinder the development of IMPE. The advantages and disadvantages of different types of photovoltaic panel materials and energy storage battery materials are analyzed in this paper, and guidance is provided on material selection for IMPE planners. The time sequential simulation method is applied to optimize material demands of the IMPE. The model is solved by parallel algorithms that are provided by a commercial solver named CPLEX. Finally, to verify the model, an actual IMPE is selected as a case system. Simulation results on the case system indicate that the optimization model and corresponding algorithm is feasible. Guidance for material selection and quantity demand for IMPEs in remote areas is provided by this method.

  10. Expanding the live kidney donor pool: ethical considerations regarding altruistic donors, paired and pooled programs.

    Science.gov (United States)

    Patel, Shaneel Rajendra; Chadha, Priyanka; Papalois, Vassilios

    2011-06-01

    In renal transplant, there is a well-known deficiency in organ supply relative to demand. Live donation provides superior results when compared with deceased donation including a better rate of graft success and fewer immunologic complications. This deficiency in organs leads to significant morbidity and mortality rates. Alternative avenues have been extensively explored that may expand the live donor pool. They include altruistic donation as well as paired and pooled exchange programs. Altruistic donation is a truly selfless act from a donor unknown to the recipient. Kidney paired donation involves 2 incompatible donor-recipient pairs swapping donors to produce compatibility. Pooled donation involves at least 2 pairs, and can take the form of domino chains in which altruistic input sets up a chain of transplants, in which each recipient's incompatible donor makes a donation for the next recipient. Despite application of these various methods, there lie extensive ethical issues surrounding them. Misconceptions frequently occur; for instance, the perceived benefit that donating an organ to a loved one is greater for a related donor than for an altruistic one. Additionally, it is frequently believed that immunologic incompatibility offers coerced donors liberation from surgery, and that overcoming these barriers by introducing exchange programs provides vulnerable donors less protection. This article explores these and other complex ethical issues surrounding the various methods of expanding the donor pool. The authors offer opinions that challenge the ethical issues and attempt to overcome those views that hinder progress in the field.

  11. Modeling coverage gaps in haplotype frequencies via Bayesian inference to improve stem cell donor selection.

    Science.gov (United States)

    Louzoun, Yoram; Alter, Idan; Gragert, Loren; Albrecht, Mark; Maiers, Martin

    2018-05-01

    Regardless of sampling depth, accurate genotype imputation is limited in regions of high polymorphism which often have a heavy-tailed haplotype frequency distribution. Many rare haplotypes are thus unobserved. Statistical methods to improve imputation by extending reference haplotype distributions using linkage disequilibrium patterns that relate allele and haplotype frequencies have not yet been explored. In the field of unrelated stem cell transplantation, imputation of highly polymorphic human leukocyte antigen (HLA) genes has an important application in identifying the best-matched stem cell donor when searching large registries totaling over 28,000,000 donors worldwide. Despite these large registry sizes, a significant proportion of searched patients present novel HLA haplotypes. Supporting this observation, HLA population genetic models have indicated that many extant HLA haplotypes remain unobserved. The absent haplotypes are a significant cause of error in haplotype matching. We have applied a Bayesian inference methodology for extending haplotype frequency distributions, using a model where new haplotypes are created by recombination of observed alleles. Applications of this joint probability model offer significant improvement in frequency distribution estimates over the best existing alternative methods, as we illustrate using five-locus HLA frequency data from the National Marrow Donor Program registry. Transplant matching algorithms and disease association studies involving phasing and imputation of rare variants may benefit from this statistical inference framework.

  12. Gamete donors' reasons for, and expectations and experiences of, registration with a voluntary donor linking register.

    Science.gov (United States)

    Blyth, Eric; Crawshaw, Marilyn; Frith, Lucy; van den Akker, Olga

    2017-12-01

    This paper reports on a study of the views and experiences of 21 sperm donors and five egg donors registered with UK DonorLink (UKDL), a voluntary DNA-based contact register established to facilitate contact between adults who wish to identify and locate others to whom they are genetically related following donor conception. Specifically, the paper examines donors' reasons for searching for, or making information about themselves available to donor-conceived offspring. Their expectations of registration with UKDL, experiences of being registered and finally, the experiences of those who had contacted donor-conceived offspring and other genetic relatives are investigated. While most respondents reported largely positive experiences of registration, the study found significant issues relating to concerns about donation, DNA testing, possible linking with offspring and expectations of any relationship that might be established with offspring that have implications for support, mediation and counselling. Research that puts the experiences, perceptions and interests of gamete donors as the central focus of study is a relatively recent phenomenon. This study contributes to this debate and highlights directions for future research in this area.

  13. Informed consent and decision-making about adult-to-adult living donor liver transplantation: a systematic review of empirical research.

    Science.gov (United States)

    Gordon, Elisa J; Daud, Amna; Caicedo, Juan Carlos; Cameron, Kenzie A; Jay, Colleen; Fryer, Jonathan; Beauvais, Nicole; Skaro, Anton; Baker, Talia

    2011-12-27

    Adult-to-adult living donor liver transplantation (LDLT) is a complex procedure that poses serious health risks to and provides no direct health benefit for the donor. Because of this uneven risk-benefit ratio, ensuring donor autonomy through informed consent is critical. To assess the current knowledge pertaining to informed consent for LDLT, we conducted a systematic review of the empirical literature on donors' decision-making process, comprehension about risks and outcomes, and information needs for LDLT. Of the 1423 identified articles, 24 met final review criteria, representing the perspective of approximately 2789 potential and actual donors. As donors' decisions to donate often occur before evaluation, they often make uninformed decisions. The review found that 88% to 95% of donors reported understanding information clinicians disclosed about risks and benefits. However, donors reported unmet information needs, knowledge gaps regarding risks, and unanticipated complications. Few donors reported feeling pressure to donate. Most studies were limited by cultural differences, small sample sizes, inconsistent measures, and poor methodological approaches. This systematic review suggests that informed consent for LDLT is sub-optimal as donors do not adequately appreciate disclosed information during the informed consent process, despite United Network for Organ Sharing/CMS regulations requiring formal psychological evaluation of donor candidates. Interventions are needed to improve donor-clinician communication during the LDLT informed consent process such as through the use of comprehension assessment tools and e-health educational tools that leverage adult learning theory to effectively convey LDLT outcome data.

  14. Impact of donor- and collection-related variables on product quality in ex utero cord blood banking.

    Science.gov (United States)

    Askari, Sabeen; Miller, John; Chrysler, Gayl; McCullough, Jeffrey

    2005-02-01

    Optimizing product quality is a current focus in cord blood banking. This study evaluates the role of selected donor- and collection-related variables. Retrospective review was performed of cord blood units (CBUs) collected ex utero between February 1, 2000, and February 28, 2002. Preprocessing volume and total nucleated cell (TNC) counts and postprocessing CD34 cell counts were used as product quality indicators. Of 2084 CBUs, volume determinations and TNC counts were performed on 1628 and CD34+ counts on 1124 CBUs. Mean volume and TNC and CD34+ counts were 85.2 mL, 118.9 x 10(7), and 5.2 x 10(6), respectively. In univariate analysis, placental weight of greater than 500 g and meconium in amniotic fluid correlated with better volume and TNC and CD34+ counts. Greater than 40 weeks' gestation predicted enhanced volume and TNC count. Cesarean section, two- versus one-person collection, and not greater than 5 minutes between placental delivery and collection produced superior volume. Increased TNC count was also seen in Caucasian women, primigravidae, female newborns, and collection duration of more than 5 minutes. A time between delivery of newborn and placenta of not greater than 10 minutes predicted better volume and CD34+ count. By regression analysis, collection within not greater than 5 minutes of placental delivery produced superior volume and TNC count. Donor selection and collection technique modifications may improve product quality. TNC count appears to be more affected by different variables than CD34+ count.

  15. Why Should Donors Care about Corruption?

    OpenAIRE

    Kolstad, Ivar

    2008-01-01

    Corruption is bad for donor business. Corruption reduces popular support for aid in donor countries. However, aid agencies should pay attention to corruption because it is the right thing to do, rather than just the smart thing to do. Donor anti-corruption policies require a strong grounding in ethics. Corruption produces bad development outcomes. This is the reasoning largely underlying donor anti-corruption efforts. The focus on consequences of corruption makes donor anticorruptioneffo...

  16. A novel variable selection approach that iteratively optimizes variable space using weighted binary matrix sampling.

    Science.gov (United States)

    Deng, Bai-chuan; Yun, Yong-huan; Liang, Yi-zeng; Yi, Lun-zhao

    2014-10-07

    In this study, a new optimization algorithm called the Variable Iterative Space Shrinkage Approach (VISSA) that is based on the idea of model population analysis (MPA) is proposed for variable selection. Unlike most of the existing optimization methods for variable selection, VISSA statistically evaluates the performance of variable space in each step of optimization. Weighted binary matrix sampling (WBMS) is proposed to generate sub-models that span the variable subspace. Two rules are highlighted during the optimization procedure. First, the variable space shrinks in each step. Second, the new variable space outperforms the previous one. The second rule, which is rarely satisfied in most of the existing methods, is the core of the VISSA strategy. Compared with some promising variable selection methods such as competitive adaptive reweighted sampling (CARS), Monte Carlo uninformative variable elimination (MCUVE) and iteratively retaining informative variables (IRIV), VISSA showed better prediction ability for the calibration of NIR data. In addition, VISSA is user-friendly; only a few insensitive parameters are needed, and the program terminates automatically without any additional conditions. The Matlab codes for implementing VISSA are freely available on the website: https://sourceforge.net/projects/multivariateanalysis/files/VISSA/.

  17. Interfacial chemistry and the design of solid-phase nucleic acid hybridization assays using immobilized quantum dots as donors in fluorescence resonance energy transfer.

    Science.gov (United States)

    Algar, W Russ; Krull, Ulrich J

    2011-01-01

    The use of quantum dots (QDs) as donors in fluorescence resonance energy transfer (FRET) offer several advantages for the development of multiplexed solid-phase QD-FRET nucleic acid hybridization assays. Designs for multiplexing have been demonstrated, but important challenges remain in the optimization of these systems. In this work, we identify several strategies based on the design of interfacial chemistry for improving sensitivity, obtaining lower limits of detection (LOD) and enabling the regeneration and reuse of solid-phase QD-FRET hybridization assays. FRET-sensitized emission from acceptor dyes associated with hybridization events at immobilized QD donors provides the analytical signal in these assays. The minimization of active sensing area reduces background from QD donor PL and allows the resolution of smaller amounts of acceptor emission, thus lowering the LOD. The association of multiple acceptor dyes with each hybridization event can enhance FRET efficiency, thereby improving sensitivity. Many previous studies have used interfacial protein layers to generate selectivity; however, transient destabilization of these layers is shown to prevent efficient regeneration. To this end, we report a protein-free interfacial chemistry and demonstrate the specific detection of as little as 2 pmol of target, as well as an improved capacity for regeneration.

  18. The Impact of Total Ischemic Time, Donor Age and the Pathway of Donor Death on Graft Outcomes After Deceased Donor Kidney Transplantation.

    Science.gov (United States)

    Wong, Germaine; Teixeira-Pinto, Armando; Chapman, Jeremy R; Craig, Jonathan C; Pleass, Henry; McDonald, Stephen; Lim, Wai H

    2017-06-01

    Prolonged ischemia is a known risk factor for delayed graft function (DGF) and its interaction with donor characteristics, the pathways of donor death, and graft outcomes may have important implications for allocation policies. Using data from the Australian and New Zealand Dialysis and Transplant registry (1994-2013), we examined the relationship between total ischemic time with graft outcomes among recipients who received their first deceased donor kidney transplants. Total ischemic time (in hours) was defined as the time of the donor renal artery interruption or aortic clamp, until the time of release of the clamp on the renal artery in the recipient. A total of 7542 recipients were followed up over a median follow-up time of 5.3 years (interquartile range of 8.2 years). Of these, 1823 (24.6%) experienced DGF and 2553 (33.9%) experienced allograft loss. Recipients with total ischemic time of 14 hours or longer experienced an increased odd of DGF compared with those with total ischemic time less than 14 hours. This effect was most marked among those with older donors (P value for interaction = 0.01). There was a significant interaction between total ischemic time, donor age, and graft loss (P value for interaction = 0.03). There was on average, a 9% increase in the overall risk of graft loss per hour increase in the total ischemic time (adjusted hazard ratio, 1.09; 95% confidence interval, 1.01-1.18; P = 0.02) in recipients with older donation after circulatory death grafts. There is a clinically important interaction between donor age, the pathway of donor death, and total ischemic time on graft outcomes, such that the duration of ischemic time has the greatest impact on graft survival in recipients with older donation after circulatory death kidneys.

  19. Donor free radical explosive composition

    Science.gov (United States)

    Walker, Franklin E. [15 Way Points Rd., Danville, CA 94526; Wasley, Richard J. [4290 Colgate Way, Livermore, CA 94550

    1980-04-01

    An improved explosive composition is disclosed and comprises a major portion of an explosive having a detonation velocity between about 1500 and 10,000 meters per second and a minor amount of a donor additive comprising an organic compound or mixture of organic compounds capable of releasing low molecular weight free radicals or ions under mechanical or electrical shock conditions and which is not an explosive, or an inorganic compound or mixture of inorganic compounds capable of releasing low molecular weight free radicals or ions under mechanical or electrical shock conditions and selected from ammonium or alkali metal persulfates.

  20. Donor conversion and procurement failure: the fate of our potential organ donors.

    Science.gov (United States)

    Branco, Bernardino C; Inaba, Kenji; Lam, Lydia; Salim, Ali; Barmparas, Galinos; Teixeira, Pedro G R; Talving, Peep; Demetriades, Demetrios

    2011-02-01

    Donor availability remains the primary limiting factor for organ transplantation today. The purpose of this study was to examine the causes of procurement failure amongst potential organ donors. After Institutional Review Board approval, all surgical intensive care unit (SICU) patients admitted to the LAC+USC Medical Center from 01/2006 to 12/2008 who became potential organ donors were identified. Demographics, clinical data, and procurement data were abstracted. In non-donors, the causes of procurement failure were documented. During the 3-year study period, a total of 254 patients were evaluated for organ donation. Mean age was 44.8±18.7 years; 191 (75.2%) were male, 136 (53.5%) were Hispanic, and 148 (58.3%) were trauma patients. Of the 254 patients, 116 (45.7%) were not eligible for donation: 34 had multi-system organ failure, 24 did not progress to brain death and had support withdrawn, 18 had uncontrolled sepsis, 15 had malignancy, 6 had human immunodeficiency virus or hepatitis B or C, and 19 patients had other contraindications to organ donation. Of the remaining 138 eligible patients, 83 (60.2%) did not donate: 56 because the family denied consent, 9 by their own choice. In six, next of kin could not be located, five died because of hemodynamic instability before organ procurement was possible, four had organs that could not be placed, and three had their organs declined by the organ procurement organization. The overall consent rate was 57.5% (n=67). From the 55 donors, 255 organs were procured (yield 4.6 organs/donor). Of all patients screened for organ donation, only a fifth actually donated. Denial of consent was the major potentially preventable cause of procurement failure, whereas hemodynamic instability accounted for only a small percentage of donor losses. With such low conversion rates, the preventable causes of procurement failure warrant further study.

  1. Donor and Acceptor Unit Sequences Influence Material Performance in Benzo[1,2-b:4,5-b′]dithiophene-6,7-Difluoroquinoxaline Small Molecule Donors for BHJ Solar Cells

    KAUST Repository

    Wang, Kai

    2016-08-22

    Well-defined small molecule (SM) donors can be used as alternatives to π-conjugated polymers in bulk-heterojunction (BHJ) solar cells with fullerene acceptors (e.g., PC61/71BM). Taking advantage of their synthetic tunability, combinations of various donor and acceptor motifs can lead to a wide range of optical, electronic, and self-assembling properties that, in turn, may impact material performance in BHJ solar cells. In this report, it is shown that changing the sequence of donor and acceptor units along the π-extended backbone of benzo[1,2-b:4,5-b\\']dithiophene-6,7-difluoroquinoxaline SM donors critically impacts (i) molecular packing, (ii) propensity to order and preferential aggregate orientations in thin-films, and (iii) charge transport in BHJ solar cells. In these systems (SM1-3), it is found that 6,7-difluoroquinoxaline ([2F]Q) motifs directly appended to the central benzo[1,2-b:4,5-b\\']dithiophene (BDT) unit yield a lower-bandgap analogue (SM1) with favorable molecular packing and aggregation patterns in thin films, and optimized BHJ solar cell efficiencies of ≈6.6%. 1H-1H DQ-SQ NMR analyses indicate that SM1 and its counterpart with [2F]Q motifs substituted as end-group SM3 possess distinct self-assembly patterns, correlating with the significant charge transport and BHJ device efficiency differences observed for the two analogous SM donors (avg. 6.3% vs 2.0%, respectively). © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Donor and Acceptor Unit Sequences Influence Material Performance in Benzo[1,2-b:4,5-b′]dithiophene-6,7-Difluoroquinoxaline Small Molecule Donors for BHJ Solar Cells

    KAUST Repository

    Wang, Kai; Liang, Ru-Ze; Wolf, Jannic Sebastian; Saleem, Qasim; Babics, Maxime; Wucher, Philipp; Abdelsamie, Maged; Amassian, Aram; Hansen, Michael Ryan; Beaujuge, Pierre

    2016-01-01

    Well-defined small molecule (SM) donors can be used as alternatives to π-conjugated polymers in bulk-heterojunction (BHJ) solar cells with fullerene acceptors (e.g., PC61/71BM). Taking advantage of their synthetic tunability, combinations of various donor and acceptor motifs can lead to a wide range of optical, electronic, and self-assembling properties that, in turn, may impact material performance in BHJ solar cells. In this report, it is shown that changing the sequence of donor and acceptor units along the π-extended backbone of benzo[1,2-b:4,5-b']dithiophene-6,7-difluoroquinoxaline SM donors critically impacts (i) molecular packing, (ii) propensity to order and preferential aggregate orientations in thin-films, and (iii) charge transport in BHJ solar cells. In these systems (SM1-3), it is found that 6,7-difluoroquinoxaline ([2F]Q) motifs directly appended to the central benzo[1,2-b:4,5-b']dithiophene (BDT) unit yield a lower-bandgap analogue (SM1) with favorable molecular packing and aggregation patterns in thin films, and optimized BHJ solar cell efficiencies of ≈6.6%. 1H-1H DQ-SQ NMR analyses indicate that SM1 and its counterpart with [2F]Q motifs substituted as end-group SM3 possess distinct self-assembly patterns, correlating with the significant charge transport and BHJ device efficiency differences observed for the two analogous SM donors (avg. 6.3% vs 2.0%, respectively). © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Outcome of Transplantation Using Organs From Donors Infected or Colonized With Carbapenem-Resistant Gram-Negative Bacteria.

    Science.gov (United States)

    Mularoni, A; Bertani, A; Vizzini, G; Gona, F; Campanella, M; Spada, M; Gruttadauria, S; Vitulo, P; Conaldi, P; Luca, A; Gridelli, B; Grossi, P

    2015-10-01

    Donor-derived infections due to multidrug-resistant bacteria are a growing problem in solid organ transplantation, and optimal management options are not clear. In a 2-year period, 30/214 (14%) recipients received an organ from 18/170 (10.5%) deceased donors with infection or colonization caused by a carbapenem-resistant gram-negative bacteria that was unknown at the time of transplantation. Among them, 14/30 recipients (47%) received a transplant from a donor with bacteremia or with infection/colonization of the transplanted organ and were considered at high risk of donor-derived infection transmission. The remaining 16/30 (53%) recipients received an organ from a nonbacteremic donor with colonization of a nontransplanted organ and were considered at low risk of infection transmission. Proven transmission occurred in 4 of the 14 high-risk recipients because donor infection was either not recognized, underestimated, or not communicated. These recipients received late, short or inappropriate posttransplant antibiotic therapy. Transmission did not occur in high-risk recipients who received appropriate and prompt antibiotic therapy for at least 7 days. The safe use of organs from donors with multidrug-resistant bacteria requires intra- and inter-institutional communication to allow appropriate management and prompt treatment of recipients in order to avoid transmission of infection. © Copyright 2015 The American Society of Transplantation and the American Society of Transplant Surgeons.

  4. Interactions of donor sources and media influence the histo-morphological quality of full-thickness skin models.

    Science.gov (United States)

    Lange, Julia; Weil, Frederik; Riegler, Christoph; Groeber, Florian; Rebhan, Silke; Kurdyn, Szymon; Alb, Miriam; Kneitz, Hermann; Gelbrich, Götz; Walles, Heike; Mielke, Stephan

    2016-10-01

    Human artificial skin models are increasingly employed as non-animal test platforms for research and medical purposes. However, the overall histopathological quality of such models may vary significantly. Therefore, the effects of manufacturing protocols and donor sources on the quality of skin models built-up from fibroblasts and keratinocytes derived from juvenile foreskins is studied. Histo-morphological parameters such as epidermal thickness, number of epidermal cell layers, dermal thickness, dermo-epidermal adhesion and absence of cellular nuclei in the corneal layer are obtained and scored accordingly. In total, 144 full-thickness skin models derived from 16 different donors, built-up in triplicates using three different culture conditions were successfully generated. In univariate analysis both media and donor age affected the quality of skin models significantly. Both parameters remained statistically significant in multivariate analyses. Performing general linear model analyses we could show that individual medium-donor-interactions influence the quality. These observations suggest that the optimal choice of media may differ from donor to donor and coincides with findings where significant inter-individual variations of growth rates in keratinocytes and fibroblasts have been described. Thus, the consideration of individual medium-donor-interactions may improve the overall quality of human organ models thereby forming a reproducible test platform for sophisticated clinical research. Copyright © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Dangerous universal donors: the reality of the Hemocentro in Belo Horizonte, Minas Gerais

    Directory of Open Access Journals (Sweden)

    Mariana Martins Godin

    Full Text Available ABSTRACT BACKGROUND: The term dangerous universal blood donor refers to potential agglutination of the erythrocytes of non-O recipients due to plasma of an O blood group donor, which contains high titers of anti-A and/or anti-B hemagglutinins. Thus, prior titration of anti-A and anti-B hemagglutinins is recommended to prevent transfusion reactions. OBJECTIVE: The aim of this study was to estimate the frequency of dangerous universal donors in the blood bank of Belo Horizonte (Fundação Central de Imuno-Hematologia - Fundação Hemominas - Minas Gerais by determining the titers of anti-A and anti-B hemagglutinins in O blood group donors. METHOD: A total of 400 O blood group donors were randomly selected, from March 2014 to January 2015. The titers of anti-A and anti-B hemagglutinins (IgM and IgG classes were obtained using the tube titration technique. Dangerous donors were those whose titers of anti-A or anti-B IgM were ≥128 and/or the titers of anti-A or anti-B IgG were ≥256. Donors were characterized according to gender, age and ethnicity. The hemagglutinins were characterized by specificity (anti-A and anti-B and antibody class (IgG and IgM. RESULTS: Almost one-third (30.5% of the O blood group donors were universal dangerous. The frequency among women was higher than that of men (p-value = 0.019; odds ratio: 1.66; 95% confidence interval: 1.08-2.56 and among young donors (18-29 years old it was higher than for donors between 49 and 59 years old (p-value = 0.015; odds ratio: 3.05; 95% confidence interval: 1.22-7.69. There was no significant association between dangerous universal donors and ethnicity, agglutinin specificity or antibody class. CONCLUSION: Especially platelet concentrates obtained by apheresis (that contain a substantial volume of plasma, coming from dangerous universal donors should be transfused in isogroup recipients whenever possible in order to prevent the occurrence of transfusion reactions.

  6. [Lack of knowledge among blood donors in Burkina Faso (West Africa); potential obstacle to transfusion security].

    Science.gov (United States)

    Nébié, K Y; Olinger, C M; Kafando, E; Dahourou, H; Diallo, S; Kientega, Y; Domo, Y; Kienou, K; Ouattara, S; Sawadogo, I; Ky, L; Muller, C P

    2007-11-01

    The measures recommended to reduce TTD include clinical selection of donors, based on a standardized questionnaire which aims to find out antecedents and behaviours predicting transmitted diseases within donors. The effectiveness of this measure is well established in the industrialized countries where the level of education of the population may support a greater receptivity of donors about this procedure. What is happening in developing one? This study was carried out to assess knowledge attitude and behaviours among blood donors regarding blood and transfusion safety in Burkina Faso. A cross sectional study was carried out in the blood bank of the teaching hospital of Ouagadougou. In addition to the routine questionnaire, 544 included blood donors were subjected to additional questions seeking to specify their behaviours, knowledge and attitude towards TTD diseases and screening. Donors were from 16 to 57 years of age (mean age : 28+/-7.9 years). The majority of donors were male (71.2%). Family donors represent 52% and first time donors 55%. About 30.8% were illiterate or of primary school level. A percentage of 14.4 donate to access HIV testing and 30.7% will donate blood immediately to check any contamination in case of exposure. There was no difference between donors having been informed about their HIV status in the past and the other donors regarding HIV, HBs Ag and VHC results. This study suggests that there is some great need for donors' education on transfusion safety. There is also need for staff training in donors' management.

  7. Selecting Optimal Feature Set in High-Dimensional Data by Swarm Search

    Directory of Open Access Journals (Sweden)

    Simon Fong

    2013-01-01

    Full Text Available Selecting the right set of features from data of high dimensionality for inducing an accurate classification model is a tough computational challenge. It is almost a NP-hard problem as the combinations of features escalate exponentially as the number of features increases. Unfortunately in data mining, as well as other engineering applications and bioinformatics, some data are described by a long array of features. Many feature subset selection algorithms have been proposed in the past, but not all of them are effective. Since it takes seemingly forever to use brute force in exhaustively trying every possible combination of features, stochastic optimization may be a solution. In this paper, we propose a new feature selection scheme called Swarm Search to find an optimal feature set by using metaheuristics. The advantage of Swarm Search is its flexibility in integrating any classifier into its fitness function and plugging in any metaheuristic algorithm to facilitate heuristic search. Simulation experiments are carried out by testing the Swarm Search over some high-dimensional datasets, with different classification algorithms and various metaheuristic algorithms. The comparative experiment results show that Swarm Search is able to attain relatively low error rates in classification without shrinking the size of the feature subset to its minimum.

  8. Philanthropic Motivations of Community College Donors

    Science.gov (United States)

    Carter, Linnie S.; Duggan, Molly H.

    2011-01-01

    This descriptive study surveyed current, lapsed, and major gift donors to explore the impact of college communications on donors' decisions to contribute to the college, the likelihood of donor financial support for various college projects, and the philanthropic motivation profiles of the donors of a midsized, multicampus community college in…

  9. Prevalence of infection in kidney transplantation from living versus deceased donor: systematic review and meta-analysis

    Directory of Open Access Journals (Sweden)

    Mônica Taminato

    2015-06-01

    Full Text Available OBJECTIVE To verify if the type of donor is a risk factor for infection in kidney transplant recipients. METHODS Systematic Review of Literature with Meta-analysis with searches conducted in the databases MEDLINE, LILACS, Embase, Cochrane, Web of Science, SciELO and CINAHL. RESULTS We selected 198 studies and included four observational studies describing infections among patients distinguishing the type of donor. Through meta-analysis, it was shown that in patients undergoing deceased donor transplant, the outcome infection was 2.65 higher, than those who received an organ from a living donor. CONCLUSION The study showed that deceased kidney donor recipients are at an increased risk for developing infections and so the need for establishing and enforcing protocols from proper management of ischemic time to the prevention and control of infection in this population emerges.

  10. Optimized bioregenerative space diet selection with crew choice

    Science.gov (United States)

    Vicens, Carrie; Wang, Carolyn; Olabi, Ammar; Jackson, Peter; Hunter, Jean

    2003-01-01

    Previous studies on optimization of crew diets have not accounted for choice. A diet selection model with crew choice was developed. Scenario analyses were conducted to assess the feasibility and cost of certain crew preferences, such as preferences for numerous-desserts, high-salt, and high-acceptability foods. For comparison purposes, a no-choice and a random-choice scenario were considered. The model was found to be feasible in terms of food variety and overall costs. The numerous-desserts, high-acceptability, and random-choice scenarios all resulted in feasible solutions costing between 13.2 and 17.3 kg ESM/person-day. Only the high-sodium scenario yielded an infeasible solution. This occurred when the foods highest in salt content were selected for the crew-choice portion of the diet. This infeasibility can be avoided by limiting the total sodium content in the crew-choice portion of the diet. Cost savings were found by reducing food variety in scenarios where the preference bias strongly affected nutritional content.

  11. Hyperopt: a Python library for model selection and hyperparameter optimization

    Science.gov (United States)

    Bergstra, James; Komer, Brent; Eliasmith, Chris; Yamins, Dan; Cox, David D.

    2015-01-01

    Sequential model-based optimization (also known as Bayesian optimization) is one of the most efficient methods (per function evaluation) of function minimization. This efficiency makes it appropriate for optimizing the hyperparameters of machine learning algorithms that are slow to train. The Hyperopt library provides algorithms and parallelization infrastructure for performing hyperparameter optimization (model selection) in Python. This paper presents an introductory tutorial on the usage of the Hyperopt library, including the description of search spaces, minimization (in serial and parallel), and the analysis of the results collected in the course of minimization. This paper also gives an overview of Hyperopt-Sklearn, a software project that provides automatic algorithm configuration of the Scikit-learn machine learning library. Following Auto-Weka, we take the view that the choice of classifier and even the choice of preprocessing module can be taken together to represent a single large hyperparameter optimization problem. We use Hyperopt to define a search space that encompasses many standard components (e.g. SVM, RF, KNN, PCA, TFIDF) and common patterns of composing them together. We demonstrate, using search algorithms in Hyperopt and standard benchmarking data sets (MNIST, 20-newsgroups, convex shapes), that searching this space is practical and effective. In particular, we improve on best-known scores for the model space for both MNIST and convex shapes. The paper closes with some discussion of ongoing and future work.

  12. Blood donor deferral: time for change? An evidence-based analysis

    Directory of Open Access Journals (Sweden)

    Borra V

    2016-05-01

    Full Text Available Vere Borra,1 Giovani Vandewalle,1 Hans Van Remoortel,1 Veerle Compernolle,1,2 Emmy De Buck,1 Philippe Vandekerckhove1–31Belgian Red Cross-Flanders, Mechelen, 2Faculty of Medicine, University of Ghent, Ghent, 3Department of Public Health and Primary Care, Faculty of Medicine, KU Leuven, Leuven, BelgiumAbstract: Donor selection remains an important part in the safety of the blood supply all over the world. Yet, donor deferral criteria seem to be strongly based on the precautionary principle protecting safety and quality, and on supply and expense considerations. This review therefore provides an overview of the available evidence on donor exclusion criteria, as well as on their cost-effectiveness, for the most frequent reasons of donor deferral in our region. PubMed was queried to retrieve primary research studies, systematic reviews, and health technology assessments (HTAs concerning donor exclusion criteria. With a similar approach, HTAs about the different blood-banking safety interventions were included. Reasons for donor deferral were recorded via the blood bank information system of the Belgian Red Cross-Flanders. Seven systematic reviews were identified: four on donor safety (hypotension, hypertension/type 2 diabetes, epilepsy, and higher age and three on recipient safety (hemochromatosis, men who have sex with men, and endoscopy. Forty-three low-quality observational studies were included, as well as 16 HTAs: three about donor exclusion criteria and 13 cost-utility analyses about blood-banking safety interventions. In general, the available evidence for deferral reasons was of low quality, and for 60% of the top 30 reasons for excluding donors, no evidence was found. Blood banking shows its unique position as many safety measures far exceed the normally accepted cost of €50,000/quality-adjusted life-years. The historical model based on the precautionary principle and on supply and expense considerations provides adequate supplies of

  13. Nanofibrillar cellulose wound dressing in skin graft donor site treatment.

    Science.gov (United States)

    Hakkarainen, T; Koivuniemi, R; Kosonen, M; Escobedo-Lucea, C; Sanz-Garcia, A; Vuola, J; Valtonen, J; Tammela, P; Mäkitie, A; Luukko, K; Yliperttula, M; Kavola, H

    2016-12-28

    Although new therapeutic approaches for burn treatment have made progress, there is still need for better methods to enhance wound healing and recovery especially in severely burned patients. Nanofibrillar cellulose (NFC) has gained attention due to its renewable nature, good biocompatibility and excellent physical properties that are of importance for a range of applications in pharmaceutical and biomedical fields. In the present study, we investigated the potential of a wood based NFC wound dressing in a clinical trial on burn patients. Previously, we have investigated NFC as a topical functionalized wound dressing that contributes to improve wound healing in mice. Wood based NFC wound dressing was tested in split-thickness skin graft donor site treatment for nine burn patients in clinical trials at Helsinki Burn Centre. NFC dressing was applied to split thickness skin graft donor sites. The dressing gradually dehydrated and attached to donor site during the first days. During the clinical trials, physical and mechanical properties of NFC wound dressing were optimized by changing its composition. From patient 5 forward, NFC dressing was compared to commercial lactocapromer dressing, Suprathel® (PMI Polymedics, Germany). Epithelialization of the NFC dressing-covered donor site was faster in comparison to Suprathel®. Healthy epithelialized skin was revealed under the detached NFC dressing. NFC dressing self-detached after 11-21days for patients 1-9, while Suprathel® self-detached after 16-28days for patients 5-9. In comparison studies with patients 5-9, NFC dressing self-detached on average 4days earlier compared with Suprathel®. Lower NFC content in the material was evaluated to influence the enhanced pliability of the dressing and attachment to the wound bed. No allergic reaction or inflammatory response to NFC was observed. NFC dressing did not cause more pain for patients than the traditional methods to treat the skin graft donor sites. Based on the

  14. Laparoscopic versus open nephrectomy for live kidney donors.

    Science.gov (United States)

    Wilson, Colin H; Sanni, Aliu; Rix, David A; Soomro, Naeem A

    2011-11-09

    Waiting lists for kidney transplantation continue to grow and live organ donation has become more important as the number of brain stem dead cadaveric organ donors continues to fall. The major disincentive to potential kidney donors is the pain and morbidity associated with open surgery. To identify the benefits and harms of using laparoscopic compared to open nephrectomy techniques to recover kidneys from live organ donors. We searched the online databases CENTRAL (in The Cochrane Library 2010, Issue 2), MEDLINE (January 1966 to January 2010) and EMBASE (January 1980 to January 2010) and handsearched textbooks and reference lists. Randomised controlled trials comparing laparoscopic donor nephrectomy (LDN) with open donor nephrectomy (ODN). Two review authors independently screened titles and abstracts for eligibility, assessed study quality, and extracted data. We contacted study authors for additional information where necessary. Six studies were identified that randomised 596 live kidney donors to either LDN or ODN arms. All studies were assessed as having low or unclear risk of bias for selection bias, allocation bias, incomplete outcome data and selective reporting bias. Four of six studies had high risk of bias for blinding. Various different combinations of techniques were used in each study, resulting in heterogeneity in the results. The conversion rate from LDN to ODN ranged from 1% to 1.8%. LDN was generally found to be associated with reduced analgesia use, shorter hospital stay, and faster return to normal physical functioning. The extracted kidney was exposed to longer warm ischaemia periods (2 to 17 minutes) with no associated short-term consequences. ODN was associated with shorter duration of procedure. For those outcomes that could be meta-analysed there were no significant differences between LDN or ODN for perioperative complications (RR 0.87, 95% CI 0.47 to 4.59), reoperations (RR 0.57, 95% CI 0.09 to 3.64), early graft loss (RR 0.31, 95% CI 0

  15. Individual, contextual and network characteristics of blood donors and non-donors: a systematic review of recent literature

    Science.gov (United States)

    Piersma, Tjeerd W.; Bekkers, René; Klinkenberg, Elisabeth F.; de Kort, Wim L.A.M.; Merz, Eva-Maria

    2017-01-01

    Background The ageing population and recent migration flows may negatively affect the blood supply in the long term, increasing the importance of targeted recruitment and retention strategies to address donors. This review sought to identify individual, network and contextual characteristics related to blood donor status and behaviour, to systematically discuss differences between study results, and to identify possible factors to target in recruitment and retention efforts. Methods The systematic review was conducted in accordance with a predefined PROSPERO protocol (CRD42016039591). After quality assessments by multiple independent raters, a final set of 66 peer-reviewed papers, published between October 2009 and January 2017, were included for review. Results Individual and contextual characteristics of blood donor status and behaviour were categorised into five main lines of research: donor demographics, motivations and barriers, adverse reactions and deferral, contextual factors, and blood centre factors. Results on donor demographics, motivations and barriers, and contextual factors were inconclusive, differing between studies, countries, and sample characteristics. Adverse reactions and deferral were negatively related to blood donor behaviour. Blood centre factors play an important role in donor management, e.g., providing information, reminders, and (non-)monetary rewards. No studies were found on network characteristics of (non-)donors. Discussion Although individual and contextual characteristics strongly relate to blood donor status and behaviour, mechanisms underlying these relations have not been studied sufficiently. We want to stress the importance of longitudinal studies in donor behaviour, exploring the role of life events and network characteristics within blood donor careers. Increased understanding of donor behaviour will assist policy makers of blood collection agencies, with the ultimate goal of safeguarding a sufficient and matching blood

  16. Individual, contextual and network characteristics of blood donors and non-donors: a systematic review of recent literature.

    Science.gov (United States)

    Piersma, Tjeerd W; Bekkers, René; Klinkenberg, Elisabeth F; De Kort, Wim L A M; Merz, Eva-Maria

    2017-09-01

    The ageing population and recent migration flows may negatively affect the blood supply in the long term, increasing the importance of targeted recruitment and retention strategies to address donors. This review sought to identify individual, network and contextual characteristics related to blood donor status and behaviour, to systematically discuss differences between study results, and to identify possible factors to target in recruitment and retention efforts. The systematic review was conducted in accordance with a predefined PROSPERO protocol (CRD42016039591). After quality assessments by multiple independent raters, a final set of 66 peer-reviewed papers, published between October 2009 and January 2017, were included for review. Individual and contextual characteristics of blood donor status and behaviour were categorised into five main lines of research: donor demographics, motivations and barriers, adverse reactions and deferral, contextual factors, and blood centre factors. Results on donor demographics, motivations and barriers, and contextual factors were inconclusive, differing between studies, countries, and sample characteristics. Adverse reactions and deferral were negatively related to blood donor behaviour. Blood centre factors play an important role in donor management, e.g., providing information, reminders, and (non-)monetary rewards. No studies were found on network characteristics of (non-)donors. Although individual and contextual characteristics strongly relate to blood donor status and behaviour, mechanisms underlying these relations have not been studied sufficiently. We want to stress the importance of longitudinal studies in donor behaviour, exploring the role of life events and network characteristics within blood donor careers. Increased understanding of donor behaviour will assist policy makers of blood collection agencies, with the ultimate goal of safeguarding a sufficient and matching blood supply.

  17. Diaphragmatic herniation following donor hepatectomy for living donor liver transplantation: a serious complication not given due recognition.

    Science.gov (United States)

    Lochan, Rajiv; Saif, Rehan; Ganjoo, Naveen; Sakpal, Mallikarjun; Panackal, Charles; Raja, Kaiser; Reddy, Jayanth; Asthana, Sonal; Jacob, Mathew

    2017-11-01

    A clear appreciation of benefits and risks associated with living donor hepatectomy is important to facilitate counselling for the donor, family, and recipient in preparation for living donor liver transplant (LDLT). We report a life-threatening complication occurring in one of our live liver donors at 12 weeks following hemi-liver donation. We experienced five donor complications among our first 50 LDLT: Clavien Grade 1, n=1; Clavien grade 2, n=3; and Clavien grade 3B, n=1. The one with Clavien grade 3B had a life-threatening diaphragmatic hernia occurring 12 weeks following hepatectomy. This was promptly recognized and emergency surgery was performed. The donor is well at 1-year follow-up. Here we provide a review of reported instances of diaphragmatic hernia following donor hepatectomy with an attempt to elucidate the pathophysiology behind such occurrence. Life-threatening donor risk needs to be balanced with recipient benefit and risk on a tripartite basis during the counselling process for LDLT. With increasing use of LDLT, we need to be aware of such life-threatening complication. Preventive measures in this regard and counselling for such complication should be incorporated into routine work-up for potential live liver donor.

  18. Crystal growth of new charge-transfer salts based on π-conjugated donor molecules

    Energy Technology Data Exchange (ETDEWEB)

    Morherr, Antonia, E-mail: morherr@stud.uni-frankfurt.de [Physikalisches Institut, Goethe-Universität Frankfurt am Main, 60438 Frankfurt am Main (Germany); Witt, Sebastian [Physikalisches Institut, Goethe-Universität Frankfurt am Main, 60438 Frankfurt am Main (Germany); Chernenkaya, Alisa [Graduate School Materials Science in Mainz, 55128 Mainz (Germany); Institut für Physik, Johannes Gutenberg-Universität, 55099 Mainz (Germany); Bäcker, Jan-Peter [Physikalisches Institut, Goethe-Universität Frankfurt am Main, 60438 Frankfurt am Main (Germany); Schönhense, Gerd [Institut für Physik, Johannes Gutenberg-Universität, 55099 Mainz (Germany); Bolte, Michael [Institut für anorganische Chemie, Goethe-Universität Frankfurt am Main, 60438 Frankfurt am Main (Germany); Krellner, Cornelius [Physikalisches Institut, Goethe-Universität Frankfurt am Main, 60438 Frankfurt am Main (Germany)

    2016-09-01

    New charge transfer crystals of π-conjugated, aromatic molecules (phenanthrene and picene) as donors were obtained by physical vapor transport. The melting behavior, optimization of crystal growth and the crystal structure are reported for charge transfer salts with (fluorinated) tetracyanoquinodimethane (TCNQ-F{sub x}, x=0, 2, 4), which was used as acceptor material. The crystal structures were determined by single-crystal X-ray diffraction. Growth conditions for different vapor pressures in closed ampules were applied and the effect of these starting conditions for crystal size and quality is reported. The process of charge transfer was investigated by geometrical analysis of the crystal structure and by infrared spectroscopy on single crystals. With these three different acceptor strengths and the two sets of donor materials, it is possible to investigate the distribution of the charge transfer systematically. This helps to understand the charge transfer process in this class of materials with π-conjugated donor molecules.

  19. Laparoscopic donor nephrectomy increases the supply of living donor kidneys: a center-specific microeconomic analysis.

    Science.gov (United States)

    Kuo, P C; Johnson, L B

    2000-05-27

    A tenet of microeconomics is that new technology will shift the supply curve to the right. Laparoscopic donor nephrectomy (LDN) is a new technique for removal of living donor kidneys. Centers performing this procedure have noted an increased number of patients presenting for donor evaluation. This has not been previously studied. The records of all LDN performed from May 1998 to February 1999 were reviewed. The following variables were examined: sex, age, related vs. unrelated donation, estimated blood loss, i.v. analgesia, length of stay, and time out of work. Donors undergoing traditional open donor nephrectomy during January 1997 to May 1998 served as the control group. A composite cost index was constructed. LDN significantly decreased length of stay, pain, and time out of work; the supply function shifted to the right. Telephone interviews revealed that 47% donated solely because of the LDN procedure. LDN increases the supply of living donor kidneys.

  20. Reimbursing live organ donors for incurred non-medical expenses: a global perspective on policies and programs.

    Science.gov (United States)

    Sickand, M; Cuerden, M S; Klarenbach, S W; Ojo, A O; Parikh, C R; Boudville, N; Garg, A X

    2009-12-01

    Methods to reimburse living organ donors for the non-medical expenses they incur have been implemented in some jurisdictions and are being considered in others. A global understanding of existing legislation and programs would help decision makers implement and optimize policies and programs. We searched for and collected data from countries that practice living organ donation. We examined legislation and programs that facilitate reimbursement, focusing on policy mechanisms, eligibility criteria, program duration and types of expenses reimbursed. Of 40 countries, reimbursement is expressly legal in 16, unclear in 18, unspecified in 6 and expressly prohibited in 1. Donor reimbursement programs exist in 21 countries; 6 have been enacted in the last 5 years. Lost income is reimbursed in 17 countries, while travel, accommodation, meal and childcare costs are reimbursed in 12 to 19 countries. Ten countries have comprehensive programs, where all major cost categories are reimbursed to some extent. Out-of-country donors are reimbursed in 10 jurisdictions. Reimbursement is conditional on donor income in 7 countries, and recipient income in 2 countries. Many nations have programs that help living donors with their financial costs. These programs differ in operation and scope. Donors in other regions of the world are without support.

  1. Reimbursing Live Organ Donors for Incurred Non-Medical Expenses: A Global Perspective on Policies and Programs

    Science.gov (United States)

    Sickand, M.; Cuerden, M. S.; Klarenbach, S. W.; Ojo, A. O.; Parikh, C. R.; Boudville, N.; Garg, A. X.

    2015-01-01

    Methods to reimburse living organ donors for the non-medical expenses they incur have been implemented in some jurisdictions and are being considered in others. A global understanding of existing legislation and programs would help decision makers implement and optimize policies and programs. We searched for and collected data from countries that practice living organ donation. We examined legislation and programs that facilitate reimbursement, focusing on policy mechanisms, eligibility criteria, program duration and types of expenses reimbursed. Of 40 countries, reimbursement is expressly legal in 16, unclear in 18, unspecified in 6 and expressly prohibited in 1. Donor reimbursement programs exist in 21 countries; 6 have been enacted in the last 5 years. Lost income is reimbursed in 17 countries, while travel, accommodation, meal and childcare costs are reimbursed in 12 to 19 countries. Ten countries have comprehensive programs, where all major cost categories are reimbursed to some extent. Out-of-country donors are reimbursed in 10 jurisdictions. Reimbursement is conditional on donor income in 7 countries, and recipient income in 2 countries. Many nations have programs that help living donors with their financial costs. These programs differ in operation and scope. Donors in other regions of the world are without support. PMID:19788503

  2. The Risk of Transplant Failure With HLA Mismatch in First Adult Kidney Allografts 2: Living Donors, Summary, Guide.

    Science.gov (United States)

    Williams, Robert C; Opelz, Gerhard; Weil, E Jennifer; McGarvey, Chelsea J; Chakkera, Harini A

    2017-05-01

    Allografts from living donors survive longer than those from deceased donors but the role of HLA mismatching in living kidney donation is still in question. We examined the effect of HLA compatibility on kidney allograft survival from living donors by studying all first adult kidney transplants performed in the United States over 25 years. Using the United Network for Organ Sharing data, we identified first kidney transplants between October 1, 1987, and December 31, 2013. Recipients were classified by their number of HLA mismatches and stratified by donor origin. Cox multivariate regression analyses adjusting for recipient and donor transplant characteristics were performed to determine impact of HLA compatibility on kidney allograft survival for all living donors and for living related and living unrelated subsets. There were 66 596 first adult transplants from living donors with 348 960 years of follow-up. We found a linear relationship between HLA mismatch and allograft survival. In adjusted analyses, among all living donors, 1 mismatch conferred a 44% higher risk, whereas 6 mismatches conferred a twofold higher risk of allograft failure. When using 0-mismatched full siblings as a reference, living-donor kidneys reduce the hazard of failure by approximately 34% when compared with deceased donors. Twenty-five years of transplant experience, stratified by donor source, was summarized and presented as a guide for allocation. These data reinforce the importance of optimizing HLA matching to further improve survival in first adult kidney allografts in the future, especially in living unrelated donations, when possible.

  3. Optimal Feature Space Selection in Detecting Epileptic Seizure based on Recurrent Quantification Analysis and Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Saleh LAshkari

    2016-06-01

    Full Text Available Selecting optimal features based on nature of the phenomenon and high discriminant ability is very important in the data classification problems. Since it doesn't require any assumption about stationary condition and size of the signal and the noise in Recurrent Quantification Analysis (RQA, it may be useful for epileptic seizure Detection. In this study, RQA was used to discriminate ictal EEG from the normal EEG where optimal features selected by combination of algorithm genetic and Bayesian Classifier. Recurrence plots of hundred samples in each two categories were obtained with five distance norms in this study: Euclidean, Maximum, Minimum, Normalized and Fixed Norm. In order to choose optimal threshold for each norm, ten threshold of ε was generated and then the best feature space was selected by genetic algorithm in combination with a bayesian classifier. The results shown that proposed method is capable of discriminating the ictal EEG from the normal EEG where for Minimum norm and 0.1˂ε˂1, accuracy was 100%. In addition, the sensitivity of proposed framework to the ε and the distance norm parameters was low. The optimal feature presented in this study is Trans which it was selected in most feature spaces with high accuracy.

  4. SVM-RFE based feature selection and Taguchi parameters optimization for multiclass SVM classifier.

    Science.gov (United States)

    Huang, Mei-Ling; Hung, Yung-Hsiang; Lee, W M; Li, R K; Jiang, Bo-Ru

    2014-01-01

    Recently, support vector machine (SVM) has excellent performance on classification and prediction and is widely used on disease diagnosis or medical assistance. However, SVM only functions well on two-group classification problems. This study combines feature selection and SVM recursive feature elimination (SVM-RFE) to investigate the classification accuracy of multiclass problems for Dermatology and Zoo databases. Dermatology dataset contains 33 feature variables, 1 class variable, and 366 testing instances; and the Zoo dataset contains 16 feature variables, 1 class variable, and 101 testing instances. The feature variables in the two datasets were sorted in descending order by explanatory power, and different feature sets were selected by SVM-RFE to explore classification accuracy. Meanwhile, Taguchi method was jointly combined with SVM classifier in order to optimize parameters C and γ to increase classification accuracy for multiclass classification. The experimental results show that the classification accuracy can be more than 95% after SVM-RFE feature selection and Taguchi parameter optimization for Dermatology and Zoo databases.

  5. Parameter Selection and Performance Comparison of Particle Swarm Optimization in Sensor Networks Localization.

    Science.gov (United States)

    Cui, Huanqing; Shu, Minglei; Song, Min; Wang, Yinglong

    2017-03-01

    Localization is a key technology in wireless sensor networks. Faced with the challenges of the sensors' memory, computational constraints, and limited energy, particle swarm optimization has been widely applied in the localization of wireless sensor networks, demonstrating better performance than other optimization methods. In particle swarm optimization-based localization algorithms, the variants and parameters should be chosen elaborately to achieve the best performance. However, there is a lack of guidance on how to choose these variants and parameters. Further, there is no comprehensive performance comparison among particle swarm optimization algorithms. The main contribution of this paper is three-fold. First, it surveys the popular particle swarm optimization variants and particle swarm optimization-based localization algorithms for wireless sensor networks. Secondly, it presents parameter selection of nine particle swarm optimization variants and six types of swarm topologies by extensive simulations. Thirdly, it comprehensively compares the performance of these algorithms. The results show that the particle swarm optimization with constriction coefficient using ring topology outperforms other variants and swarm topologies, and it performs better than the second-order cone programming algorithm.

  6. Parameter Selection and Performance Comparison of Particle Swarm Optimization in Sensor Networks Localization

    Directory of Open Access Journals (Sweden)

    Huanqing Cui

    2017-03-01

    Full Text Available Localization is a key technology in wireless sensor networks. Faced with the challenges of the sensors’ memory, computational constraints, and limited energy, particle swarm optimization has been widely applied in the localization of wireless sensor networks, demonstrating better performance than other optimization methods. In particle swarm optimization-based localization algorithms, the variants and parameters should be chosen elaborately to achieve the best performance. However, there is a lack of guidance on how to choose these variants and parameters. Further, there is no comprehensive performance comparison among particle swarm optimization algorithms. The main contribution of this paper is three-fold. First, it surveys the popular particle swarm optimization variants and particle swarm optimization-based localization algorithms for wireless sensor networks. Secondly, it presents parameter selection of nine particle swarm optimization variants and six types of swarm topologies by extensive simulations. Thirdly, it comprehensively compares the performance of these algorithms. The results show that the particle swarm optimization with constriction coefficient using ring topology outperforms other variants and swarm topologies, and it performs better than the second-order cone programming algorithm.

  7. Optimal relay selection and power allocation for cognitive two-way relaying networks

    KAUST Repository

    Pandarakkottilil, Ubaidulla; Aï ssa, Sonia

    2012-01-01

    In this paper, we present an optimal scheme for power allocation and relay selection in a cognitive radio network where a pair of cognitive (or secondary) transceiver nodes communicate with each other assisted by a set of cognitive two-way relays

  8. Optimal individual supervised hyperspectral band selection distinguishing savannah trees at leaf level

    CSIR Research Space (South Africa)

    Debba, Pravesh

    2009-08-01

    Full Text Available computer intensive search technique to find the bands optimizing the value of TSAM as a function of the bands, by continually updating this function at succes- sive steps. Band selection by means of minimizing the total accumulated correlation...

  9. Adult-to-Adult Living Donor Liver Transplantation

    Directory of Open Access Journals (Sweden)

    Shimul A Shah

    2006-01-01

    Full Text Available The present review outlines the principles of living donor liver transplantation, donor workup, procedure and outcomes. Living donation offers a solution to the growing gap between the need for liver transplants and the limited availability of deceased donor organs. With a multidisciplinary team focused on donor safety and experienced surgeons capable of performing complex resection/reconstruction procedures, donor morbidity is low and recipient outcomes are comparable with results of deceased donor transplantation.

  10. Independent organ donor facilities: The future of organ donation?

    Science.gov (United States)

    Bruzzone, Paolo

    2014-01-01

    Since 2001 independent Organ Donor Facilities(OFOs) have been proposed within Organ Procurement Organizations (OPOs) with the aim of reducing organ procurement costs 1, cold ischemia time of donor organs and the flight-related risk 2 for donor surgeons, perfusionists and coordinators. An independent OFO has been established in 2001 in St. Louis 3, half away between the 2 Transplant Centers (TCs) (Washington University School of Medicine and St. Louis University) and now includes a two-bed intensive care facility, a complete laboratory, a cardiac catheterization facility, a Computed Tomography (CT) scanner and an operating room. All brain-dead (BD) patients within OPO (Mid-America Transplant Services), after family's informed consent, are transferred, if necessary by an OPO owned and operated airplane, to this facility, where undergo multiorgan harvesting. By doing so the organ acquisition charges (OACs) apparently decreased, as well as delay in recovery, which can affect organ viability and move families to withdraw consent; also risks and tiring of transplant surgeons were reduced. This independent OFO successfully procured in 2001 not only livers, but also pancreas, kidneys, hearts and lungs 4-6. Cold ischemia time was reduced and there was no Primary Non Function (PNF) of harvested organs, but only kidney delayed graft function (DGF). In the past, heart donors were moved to the recipient's hospital. With the development of multiorgan harvesting, usually donor surgeons are sent by the TCs in order to evaluate liver, pancreas, heart and lungs, while the only local surgeons is the "nephrectomist", that in local hospital is not a transplant surgeon. To move a donor, although hemodinamically stable, is always a risk. Finally, the decrease of OAC must balance the extra expenses to create and operate independent OFOs. In all the papers published by the members of this OFO, the control group of the retrospective analysis consisted of less selected BD donors, requiring

  11. Optimal Channel Selection Based on Online Decision and Offline Learning in Multichannel Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Mu Qiao

    2017-01-01

    Full Text Available We propose a channel selection strategy with hybrid architecture, which combines the centralized method and the distributed method to alleviate the overhead of access point and at the same time provide more flexibility in network deployment. By this architecture, we make use of game theory and reinforcement learning to fulfill the optimal channel selection under different communication scenarios. Particularly, when the network can satisfy the requirements of energy and computational costs, the online decision algorithm based on noncooperative game can help each individual sensor node immediately select the optimal channel. Alternatively, when the network cannot satisfy the requirements of energy and computational costs, the offline learning algorithm based on reinforcement learning can help each individual sensor node to learn from its experience and iteratively adjust its behavior toward the expected target. Extensive simulation results validate the effectiveness of our proposal and also prove that higher system throughput can be achieved by our channel selection strategy over the conventional off-policy channel selection approaches.

  12. Optimized Irregular Low-Density Parity-Check Codes for Multicarrier Modulations over Frequency-Selective Channels

    Directory of Open Access Journals (Sweden)

    Valérian Mannoni

    2004-09-01

    Full Text Available This paper deals with optimized channel coding for OFDM transmissions (COFDM over frequency-selective channels using irregular low-density parity-check (LDPC codes. Firstly, we introduce a new characterization of the LDPC code irregularity called “irregularity profile.” Then, using this parameterization, we derive a new criterion based on the minimization of the transmission bit error probability to design an irregular LDPC code suited to the frequency selectivity of the channel. The optimization of this criterion is done using the Gaussian approximation technique. Simulations illustrate the good performance of our approach for different transmission channels.

  13. The Effect of Exit Strategy on Optimal Portfolio Selection with Birandom Returns

    OpenAIRE

    Cao, Guohua; Shan, Dan

    2013-01-01

    The aims of this paper are to use a birandom variable to denote the stock return selected by some recurring technical patterns and to study the effect of exit strategy on optimal portfolio selection with birandom returns. Firstly, we propose a new method to estimate the stock return and use birandom distribution to denote the final stock return which can reflect the features of technical patterns and investors' heterogeneity simultaneously; secondly, we build a birandom safety-first model and...

  14. Peer-to-peer milk donors' and recipients' experiences and perceptions of donor milk banks.

    Science.gov (United States)

    Gribble, Karleen D

    2013-07-01

    To explore the intersection of peer-to-peer milk sharing and donor milk banks. A descriptive survey design containing closed and open-ended questions was used to examine women's perceptions of peer-to-peer milk sharing and milk banking. Closed-ended questions were analyzed using descriptive statistics and conventional qualitative content analysis was used to analyze open-ended responses. Participants were recruited via the Facebook sites of two online milk-sharing networks (Human Milk 4 Human Babies and Eats on Feet). Ninety-eight milk donors and 41 milk recipients who had donated or received breast milk in an arrangement that was facilitated via the Internet. One half of donor recipients could not donate to a milk bank because there were no banks local to them or they did not qualify as donors. Other respondents did not donate to a milk bank because they viewed the process as difficult, had philosophical objections to milk banking, or had a philosophical attraction to peer sharing. Most donor respondents felt it was important to know the circumstances of their milk recipients. No recipient respondents had obtained milk from a milk bank; it was recognized that they would not qualify for banked milk or that banked milk was cost prohibitive. Peer-to-peer milk donors and recipients may differ from milk bank donors and recipients in significant ways. Cooperation between milk banks and peer sharing networks could benefit both groups. © 2013 AWHONN, the Association of Women's Health, Obstetric and Neonatal Nurses.

  15. Fuzzy 2-partition entropy threshold selection based on Big Bang–Big Crunch Optimization algorithm

    Directory of Open Access Journals (Sweden)

    Baljit Singh Khehra

    2015-03-01

    Full Text Available The fuzzy 2-partition entropy approach has been widely used to select threshold value for image segmenting. This approach used two parameterized fuzzy membership functions to form a fuzzy 2-partition of the image. The optimal threshold is selected by searching an optimal combination of parameters of the membership functions such that the entropy of fuzzy 2-partition is maximized. In this paper, a new fuzzy 2-partition entropy thresholding approach based on the technology of the Big Bang–Big Crunch Optimization (BBBCO is proposed. The new proposed thresholding approach is called the BBBCO-based fuzzy 2-partition entropy thresholding algorithm. BBBCO is used to search an optimal combination of parameters of the membership functions for maximizing the entropy of fuzzy 2-partition. BBBCO is inspired by the theory of the evolution of the universe; namely the Big Bang and Big Crunch Theory. The proposed algorithm is tested on a number of standard test images. For comparison, three different algorithms included Genetic Algorithm (GA-based, Biogeography-based Optimization (BBO-based and recursive approaches are also implemented. From experimental results, it is observed that the performance of the proposed algorithm is more effective than GA-based, BBO-based and recursion-based approaches.

  16. Portfolio optimization for seed selection in diverse weather scenarios.

    Science.gov (United States)

    Marko, Oskar; Brdar, Sanja; Panić, Marko; Šašić, Isidora; Despotović, Danica; Knežević, Milivoje; Crnojević, Vladimir

    2017-01-01

    The aim of this work was to develop a method for selection of optimal soybean varieties for the American Midwest using data analytics. We extracted the knowledge about 174 varieties from the dataset, which contained information about weather, soil, yield and regional statistical parameters. Next, we predicted the yield of each variety in each of 6,490 observed subregions of the Midwest. Furthermore, yield was predicted for all the possible weather scenarios approximated by 15 historical weather instances contained in the dataset. Using predicted yields and covariance between varieties through different weather scenarios, we performed portfolio optimisation. In this way, for each subregion, we obtained a selection of varieties, that proved superior to others in terms of the amount and stability of yield. According to the rules of Syngenta Crop Challenge, for which this research was conducted, we aggregated the results across all subregions and selected up to five soybean varieties that should be distributed across the network of seed retailers. The work presented in this paper was the winning solution for Syngenta Crop Challenge 2017.

  17. Portfolio optimization for seed selection in diverse weather scenarios.

    Directory of Open Access Journals (Sweden)

    Oskar Marko

    Full Text Available The aim of this work was to develop a method for selection of optimal soybean varieties for the American Midwest using data analytics. We extracted the knowledge about 174 varieties from the dataset, which contained information about weather, soil, yield and regional statistical parameters. Next, we predicted the yield of each variety in each of 6,490 observed subregions of the Midwest. Furthermore, yield was predicted for all the possible weather scenarios approximated by 15 historical weather instances contained in the dataset. Using predicted yields and covariance between varieties through different weather scenarios, we performed portfolio optimisation. In this way, for each subregion, we obtained a selection of varieties, that proved superior to others in terms of the amount and stability of yield. According to the rules of Syngenta Crop Challenge, for which this research was conducted, we aggregated the results across all subregions and selected up to five soybean varieties that should be distributed across the network of seed retailers. The work presented in this paper was the winning solution for Syngenta Crop Challenge 2017.

  18. Adverse events and retention of donors of double red cell units by apheresis

    Science.gov (United States)

    Keshelashvili, Ketevan; O’Meara, Alix; Stern, Martin; Jirout, Zuzana; Pehlic, Vildana; Holbro, Andreas; Buser, Andreas; Sigle, Jörg; Infanti, Laura

    2016-01-01

    Background Safety of double-erythrocyte (2RBC) collection and reasons for ceasing 2RBC donation were retrospectively analysed in the blood donor population of Basel, Switzerland. Methods Donors with at least 1 2RBC apheresis were included in the study. Minimal requirements were Hb ≥140 g/L and body weight ≥70 kg; serum ferritin (SF) values were measured routinely, but were not part of the selection criteria. 2RBC collections were performed with ALYX devices at 6-month intervals. Adverse events (AEs) were systematically recorded and classified according to the ISBT EHN 2008 criteria. Data of procedures were retrieved from the ALYX software. Demographics, apheresis data and AEs were analysed with descriptive statistics. Results Data of 4,377 2RBC aphereses performed in 793 donors (779 males) between 1st January 2003 and 31st May 2015 were evaluated. Mean donor age at first 2RBC donation was 44 years (standard deviation [SD] 21), median number of donations was 4 (interquartile range [IQR] 8); 32% of the donors underwent a single procedure. There were 161 AEs, mostly local haematomas (55%) and vasovagal reactions (20%); fatigue was reported in 6% of the cases and was more frequent than citrate toxicity. Two severe AEs were observed. The most frequent reasons for abandoning 2RBC donation were low SF levels and donor choice (both 11%), but most donors simply did not reply to invitations (16%). Overall, procedure-related causes (AEs, low SF levels, no time for apheresis, inadequate venous access) were observed in 14% of the cases. At the end of the observation period, 40% of the donors were still active blood donors, but only 20% were donating 2RBC. Discussion 2RBC donation is overall safe. Donor retention was low over a period of 11 years. An important reason for abandoning 2RBC was the detection of low SF levels. The impact of fatigue on donor retention and the course of iron stores after repeated 6-monthly 2RBC apheresis require further investigation. PMID:27136442

  19. Reducing residual stresses and deformations in selective laser melting through multi-level multi-scale optimization of cellular scanning strategy

    DEFF Research Database (Denmark)

    Mohanty, Sankhya; Hattel, Jesper Henri

    2016-01-01

    . A multilevel optimization strategy is adopted using a customized genetic algorithm developed for optimizing cellular scanning strategy for selective laser melting, with an objective of reducing residual stresses and deformations. The resulting thermo-mechanically optimized cellular scanning strategies......, a calibrated, fast, multiscale thermal model coupled with a 3D finite element mechanical model is used to simulate residual stress formation and deformations during selective laser melting. The resulting reduction in thermal model computation time allows evolutionary algorithm-based optimization of the process...

  20. Lobar lung transplantation from deceased donors: A systematic review.

    Science.gov (United States)

    Eberlein, Michael; Reed, Robert M; Chahla, Mayy; Bolukbas, Servet; Blevins, Amy; Van Raemdonck, Dirk; Stanzi, Alessia; Inci, Ilhan; Marasco, Silvana; Shigemura, Norihisa; Aigner, Clemens; Deuse, Tobias

    2017-02-24

    To systematically review reports on deceased-donor-lobar lung transplantation (ddLLTx) and uniformly describe size matching using the donor-to-recipient predicted-total lung-capacity (pTLC) ratio. We set out to systematically review reports on ddLLTx and uniformly describe size matching using the donor-to-recipient pTLC ratio and to summarize reported one-year survival data of ddLLTx and conventional-LTx. We searched in PubMed, CINAHL via EBSCO, Cochrane Database of Systematic Reviews via Wiley (CDSR), Database of Abstracts of Reviews of Effects via Wiley (DARE), Cochrane Central Register of Controlled Trials via Wiley (CENTRAL), Scopus (which includes EMBASE abstracts), and Web of Science for original reports on ddLLTx. Nine observational cohort studies reporting on 301 ddLLTx met our inclusion criteria for systematic review of size matching, and eight for describing one-year-survival. The ddLLTx-group was often characterized by high acuity; however there was heterogeneity in transplant indications and pre-operative characteristics between studies. Data to calculate the pTLC ratio was available for 242 ddLLTx (80%). The mean pTLCratio before lobar resection was 1.25 ± 0.3 and the transplanted pTLCratio after lobar resection was 0.76 ± 0.2. One-year survival in the ddLLTx-group ranged from 50%-100%, compared to 72%-88% in the conventional-LTx group. In the largest study ddLLTx ( n = 138) was associated with a lower one-year-survival compared to conventional-LTx ( n = 539) (65.1% vs 84.1%, P < 0.001). Further investigations of optimal donor-to-recipient size matching parameters for ddLLTx could improve outcomes of this important surgical option.

  1. Stress predicts the trajectory of wound healing in living kidney donors as measured by high-resolution ultrasound.

    Science.gov (United States)

    Maple, Hannah; Chilcot, Joseph; Lee, Vanessa; Simmonds, Shanique; Weinman, John; Mamode, Nizam

    2015-01-01

    Psychological stress has been shown to be an influential factor on the rate of wound healing; however these findings have been demonstrated predominantly on artificially created wounds. Due to the absence of major co-morbidities, living kidney donors are a unique group in which to study this relationship. This study investigated the effect of preoperative stress and personality on surgical wound healing through the use of high-resolution ultrasound. Living kidney donors due to undergo a hand-assisted laparoscopic donor nephrectomy were asked to complete the Perceived Stress Scale, the Life Orientation Test-Revised and the Ten Item Personality Inventory prior to surgery. High-resolution ultrasound scans of surgical wounds were performed on the first three post-operative days and once following discharge (mean=15.3 days; s.d. 2.8). Two measurements from each image were obtained: wound width (size of wound) and median intensity (a marker of tissue fluid). Latent Growth Curve Models (LGCMs) were used to evaluate wound healing. 52 living kidney donors participated. Higher pre-operative life stress, lower optimism and lower conscientiousness were associated with delayed wound healing in living kidney donors for both outcomes. Increased emotional stability was associated with faster wound healing as demonstrated by a change in median intensity. Possible confounding factors, such as age, BMI, smoking status, local anaesthetic use and wound drain placement were not influential. This study, which measured wound healing in a novel patient sample using a novel technique, has demonstrated a negative association between stress and wound healing and the positive influence of optimism, conscientiousness and emotional stability. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Liver transplantation using organs from deceased organ donors: a single organ transplant center experience.

    Science.gov (United States)

    Han, Ming; Guo, Zhi-Yong; Zhao, Qiang; Wang, Xiao-Ping; Yuan, Xiao-Peng; Jiao, Xing-Yuan; Yang, Chun-Hua; Wang, Dong-Ping; Ju, Wei-Qiang; Wu, Lin-Wei; Hu, An-Bin; Tai, Qiang; Ma, Yi; Zhu, Xiao-Feng; He, Xiao-Shun

    2014-08-01

    In 2011, a pilot program for deceased organ donation was initiated in China. We describe the first successful series of liver transplants in the pilot program. From July 2011 to August 2012, our center performed 26 liver transplants from a pool of 29 deceased donors. All organ donation and allograft procurement were conducted according to the national protocol. The clinical data of donors and recipients were collected and summarized retrospectively. Among the 29 donors, 24 were China Category II donors (organ donation after cardiac death), and five were China Category III donors (organ donation after brain death followed by cardiac death). The recipients were mainly the patients with hepatocellular carcinoma. The one-year patient survival rate was 80.8% with a median follow-up of 422 (2-696) days. Among the five mortalities during the follow-up, three died of tumor recurrence. In terms of post-transplant complications, 9 recipients (34.6%) experienced early allograft dysfunction, 1 (3.8%) had non-anastomotic biliary stricture, and 1 (3.8%) was complicated with hepatic arterial thrombosis. None of these complications resulted in patient death. Notably, primary non-function was not observed in any of the grafts. With careful donor selection, liver transplant from deceased donors can be performed safely and plays a critical role in overcoming the extreme organ shortage in China.

  3. PREDICTIVE VALUE OF CD34+ CELLS IN BLOOD OF PATIENT/DONOR BEFORE HEMATOPOIETIC STEM CELLS COLLECTION BY LEUKAPHERESIS

    Directory of Open Access Journals (Sweden)

    Dragoslav Domanovič

    2004-12-01

    Full Text Available Background. In the study we tried to define a predictive value of the circulating CD34+ cells in patients/ donors blood for estimation of the hematopoietic stem cells (HSC collection efficacy determine the optimal time to initiate the collection by leukapheresis procedure.Methods. We retrospectively analyzed 75 collections of HSC using the Amicus cell separator in 39 patients and 15 donors. Circulating CD34+cell counts in patients/donors were compared to the achieved CD34+ cell yields to determine its predictive value for the collection of a targeted yield of > 2 × 106 CD34+ cells/kg body weight of patient.Results. The results of cell counts confirmed that mobilization regimens were successful and HSC collections efficient. High correlation coefficient (r = 0.82 between the number of circulating CD34+ cells before collection and CD34+ cell yield/kg of patient’s body weight was statistically significant (p < 0.05. With ROC analysis we determined the cut-off value 42 × 106/l CD34+ cell counts in the blood of patients/donors before collection that had a positive predictive value 87% and a negative predictive value 91.6%.Conclusions. Analysis showed that the number of circulating CD34+ cells before the procedure express a very high predictive value and can be used for determining the optimal time to initiate collection of HSC by leukapheresis.

  4. Optimization of multi-environment trials for genomic selection based on crop models.

    Science.gov (United States)

    Rincent, R; Kuhn, E; Monod, H; Oury, F-X; Rousset, M; Allard, V; Le Gouis, J

    2017-08-01

    We propose a statistical criterion to optimize multi-environment trials to predict genotype × environment interactions more efficiently, by combining crop growth models and genomic selection models. Genotype × environment interactions (GEI) are common in plant multi-environment trials (METs). In this context, models developed for genomic selection (GS) that refers to the use of genome-wide information for predicting breeding values of selection candidates need to be adapted. One promising way to increase prediction accuracy in various environments is to combine ecophysiological and genetic modelling thanks to crop growth models (CGM) incorporating genetic parameters. The efficiency of this approach relies on the quality of the parameter estimates, which depends on the environments composing this MET used for calibration. The objective of this study was to determine a method to optimize the set of environments composing the MET for estimating genetic parameters in this context. A criterion called OptiMET was defined to this aim, and was evaluated on simulated and real data, with the example of wheat phenology. The MET defined with OptiMET allowed estimating the genetic parameters with lower error, leading to higher QTL detection power and higher prediction accuracies. MET defined with OptiMET was on average more efficient than random MET composed of twice as many environments, in terms of quality of the parameter estimates. OptiMET is thus a valuable tool to determine optimal experimental conditions to best exploit MET and the phenotyping tools that are currently developed.

  5. [Hyperspectral remote sensing image classification based on SVM optimized by clonal selection].

    Science.gov (United States)

    Liu, Qing-Jie; Jing, Lin-Hai; Wang, Meng-Fei; Lin, Qi-Zhong

    2013-03-01

    Model selection for support vector machine (SVM) involving kernel and the margin parameter values selection is usually time-consuming, impacts training efficiency of SVM model and final classification accuracies of SVM hyperspectral remote sensing image classifier greatly. Firstly, based on combinatorial optimization theory and cross-validation method, artificial immune clonal selection algorithm is introduced to the optimal selection of SVM (CSSVM) kernel parameter a and margin parameter C to improve the training efficiency of SVM model. Then an experiment of classifying AVIRIS in India Pine site of USA was performed for testing the novel CSSVM, as well as a traditional SVM classifier with general Grid Searching cross-validation method (GSSVM) for comparison. And then, evaluation indexes including SVM model training time, classification overall accuracy (OA) and Kappa index of both CSSVM and GSSVM were all analyzed quantitatively. It is demonstrated that OA of CSSVM on test samples and whole image are 85.1% and 81.58, the differences from that of GSSVM are both within 0.08% respectively; And Kappa indexes reach 0.8213 and 0.7728, the differences from that of GSSVM are both within 0.001; While the ratio of model training time of CSSVM and GSSVM is between 1/6 and 1/10. Therefore, CSSVM is fast and accurate algorithm for hyperspectral image classification and is superior to GSSVM.

  6. Space-planning and structural solutions of low-rise buildings: Optimal selection methods

    Science.gov (United States)

    Gusakova, Natalya; Minaev, Nikolay; Filushina, Kristina; Dobrynina, Olga; Gusakov, Alexander

    2017-11-01

    The present study is devoted to elaboration of methodology used to select appropriately the space-planning and structural solutions in low-rise buildings. Objective of the study is working out the system of criteria influencing the selection of space-planning and structural solutions which are most suitable for low-rise buildings and structures. Application of the defined criteria in practice aim to enhance the efficiency of capital investments, energy and resource saving, create comfortable conditions for the population considering climatic zoning of the construction site. Developments of the project can be applied while implementing investment-construction projects of low-rise housing at different kinds of territories based on the local building materials. The system of criteria influencing the optimal selection of space-planning and structural solutions of low-rise buildings has been developed. Methodological basis has been also elaborated to assess optimal selection of space-planning and structural solutions of low-rise buildings satisfying the requirements of energy-efficiency, comfort and safety, and economical efficiency. Elaborated methodology enables to intensify the processes of low-rise construction development for different types of territories taking into account climatic zoning of the construction site. Stimulation of low-rise construction processes should be based on the system of approaches which are scientifically justified; thus it allows enhancing energy efficiency, comfort, safety and economical effectiveness of low-rise buildings.

  7. Increasing the supply of kidneys for transplantation by making living donors the preferred source of donor kidneys.

    Science.gov (United States)

    Testa, Giuliano; Siegler, Mark

    2014-12-01

    At the present time, increasing the use of living donors offers the best solution to the organ shortage problem. The clinical questions raised when the first living donor kidney transplant was performed, involving donor risk, informed consent, donor protection, and organ quality, have been largely answered. We strongly encourage a wider utilization of living donation and recommend that living donation, rather than deceased donation, become the first choice for kidney transplantation. We believe that it is ethically sound to have living kidney donation as the primary source for organs when the mortality and morbidity risks to the donor are known and kept extremely low, when the donor is properly informed and protected from coercion, and when accepted national and local guidelines for living donation are followed.

  8. Comparison of donor, and early and late recipient outcomes following hand assisted and laparoscopic donor nephrectomy.

    Science.gov (United States)

    Lucas, Steven M; Liaw, Aron; Mhapsekar, Rishi; Yelfimov, Daniel; Goggins, William C; Powelson, John A; Png, Keng Siang; Sundaram, Chandru P

    2013-02-01

    While laparoscopic donor nephrectomy has encouraged living kidney donation, debate exists about the safest laparoscopic technique. We compared purely laparoscopic and hand assisted laparoscopic donor nephrectomies in terms of donor outcome, early graft function and long-term graft outcome. We reviewed the records of consecutive laparoscopic and hand assisted laparoscopic donor nephrectomies performed by a single surgeon from 2002 to 2011. Donor operative time and perioperative morbidity were compared. Early graft function for kidneys procured by each technique was evaluated by rates of delayed graft function, need for dialysis and recipient discharge creatinine. Long-term outcomes were evaluated by graft function. A total of 152 laparoscopic donor nephrectomies were compared with 116 hand assisted laparoscopic donor nephrectomies. Hand assisted procedures were more often done for the right kidney (41.1% vs 17.1%, p recipient outcomes were also similar. Delayed function occurred after 0% hand assisted vs 0.9% purely laparoscopic nephrectomies, dialysis was required in 0.9% vs 1.7% and rejection episodes developed in 9.7% vs 18.4% (p >0.05). At last followup the organ was nonfunctioning in 6.1% of hand assisted and 7.7% of purely laparoscopic cases (p >0.05). The recipient glomerular filtration rate at discharge home was similar in the 2 groups. Hand assisted laparoscopic donor nephrectomy had shorter warm ischemia time but perioperative donor morbidity and graft outcome were comparable. The choice of technique should be based on patient and surgeon preference. Copyright © 2013 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  9. Donor Telomere Length SAA

    Science.gov (United States)

    A new NCI study has found that, among patients with severe aplastic anemia who received a hematopoietic cell transplant from an unrelated donor, those whose donor white blood cells had longer telomeres had higher survival rates five-years after transplant

  10. The early implementation of Trypanosoma cruzi antibody screening of donors and donations within England: preempting a problem.

    Science.gov (United States)

    Kitchen, Alan D; Hewitt, Patricia E; Chiodini, Peter L

    2012-09-01

    Trypanosoma cruzi is a parasitic infection endemic in Central and Southern America, but is spreading into nonendemic countries with migration of infected individuals from endemic countries. The parasite is transmitted by transfusion or transplantation and donation screening is performed routinely in endemic countries to prevent transmission. In situations where migrants from endemic countries have settled in nonendemic countries and present as donors (blood or other cellular products), intervention is required to prevent transfusion or transplantation transmission. A screening program for T. cruzi was developed and has been used successfully for over 10 years that includes donor selection and donation screening. Donor selection criteria to identify specific risk of T. cruzi infection were developed together with laboratory screening of donations for T. cruzi antibodies and the subsequent confirmation of screen reactivity. Since the introduction of T. cruzi screening in England in 1998, a total of 38,585 donors and donations have been screened for T. cruzi antibodies, of which 223 were repeat reactive on screening and referred for confirmation: 206 confirmed negative, 14 inconclusive, and three positive. Since the move in 2005 from donor qualification to donation release testing, 15,536 donations were collected and screened, of which 15,499 (99.8%) were T. cruzi antibody negative and released to inventory. An effective program to minimize risk of the transmission of T. cruzi infection via donations has been developed and implemented. Not only does the program minimize risk of transmission, it also minimizes the cumulative, and needless, loss of donors and donations that would ensue if permanent donor deferral alone was adopted. © 2012 American Association of Blood Banks.

  11. A reliable computational workflow for the selection of optimal screening libraries.

    Science.gov (United States)

    Gilad, Yocheved; Nadassy, Katalin; Senderowitz, Hanoch

    2015-01-01

    The experimental screening of compound collections is a common starting point in many drug discovery projects. Successes of such screening campaigns critically depend on the quality of the screened library. Many libraries are currently available from different vendors yet the selection of the optimal screening library for a specific project is challenging. We have devised a novel workflow for the rational selection of project-specific screening libraries. The workflow accepts as input a set of virtual candidate libraries and applies the following steps to each library: (1) data curation; (2) assessment of ADME/T profile; (3) assessment of the number of promiscuous binders/frequent HTS hitters; (4) assessment of internal diversity; (5) assessment of similarity to known active compound(s) (optional); (6) assessment of similarity to in-house or otherwise accessible compound collections (optional). For ADME/T profiling, Lipinski's and Veber's rule-based filters were implemented and a new blood brain barrier permeation model was developed and validated (85 and 74 % success rate for training set and test set, respectively). Diversity and similarity descriptors which demonstrated best performances in terms of their ability to select either diverse or focused sets of compounds from three databases (Drug Bank, CMC and CHEMBL) were identified and used for diversity and similarity assessments. The workflow was used to analyze nine common screening libraries available from six vendors. The results of this analysis are reported for each library providing an assessment of its quality. Furthermore, a consensus approach was developed to combine the results of these analyses into a single score for selecting the optimal library under different scenarios. We have devised and tested a new workflow for the rational selection of screening libraries under different scenarios. The current workflow was implemented using the Pipeline Pilot software yet due to the usage of generic

  12. Open-Identity Sperm Donation: How Does Offering Donor-Identifying Information Relate to Donor-Conceived Offspring's Wishes and Needs?

    Science.gov (United States)

    Ravelingien, An; Provoost, Veerle; Pennings, Guido

    2015-09-01

    Over the past years, a growing number of countries have legislated open-identity donation, in which donor-conceived offspring are given access to the donor's identity once the child has reached maturity. It is held that donor anonymity creates identity problems for such children similar to the "genealogical bewilderment" described within the adoption context. The study of the social and psychological effects of open-identity donation is still very much in its infancy, but what has been left unquestioned is whether (and to what extent) offering access to the donor's name and address is an adequate response to such effects. This study has two goals: First, we aim to provide a systematic review of the reasons why donor-conceived (DC) offspring want to know the identity of their sperm donor. Second, we examine to what extent the provision of donor-identifying information can satisfy the reasons mentioned. The most important motivations appear to be: (1) to avoid medical risks and consanguineous relationships; (2) to satisfy curiosity; (3) to learn more about the self or to complete one's identity; (4) to learn more about what kind of person the donor is (biographical information, why he donated, etc.); (5) to form a relationship with the donor and/or his family; and (6) to learn about one's ancestry/genealogy. Our analysis shows that for nearly all of these reasons access to the donor's identity is not necessary. In those cases where it is, moreover, donor identification is not sufficient. What is really needed is (extended) contact with the donor, rather than the mere provision of his name.

  13. Deceased donor organ transplantation with expanded criteria donors: a single-center experience from India.

    Science.gov (United States)

    Goplani, K R; Firoz, A; Ramakrishana, P; Shah, P R; Gumber, M R; Patel, H V; Vanikar, A V; Trivedi, H L

    2010-01-01

    Deceased donor organ transplantation (DDOT) accounts for DKT) and 19 single (SKT). Fourteen donors had hypertension, a cerebrovascular accident as the cause of death, 9 had both, and 4 had diabetes. Mean donor age was 70.3 +/- 8.9 years. Decisions on the procedure were based upon frozen section biopsy in 13 of 21 donors. Mean DKT donor age was 76 +/- 9.7 years versu 64 +/- 5.7 years of SKT donors. The native kidney diseases were chronic glomerulonephritis (n = 14), diabetic nephropathy (n = 7), tubulointerstitial nephritis (n = 4) and polycystic kidney disease, focal segmental glomerulosclerosis, lupus nephritis and patchy cortical necrosis, (n = 1 each). Mean recipient age of DKT versus SKT was 43.5 versus 42.3 years. All recipients received rabbit anti-thymocyte globulin, followed by steroid, mycophenolate mofetil/calcinueurin inhibitor. Over a mean follow-up of 341 days, the mean serum creatinine (SCr) of 25/29 patients was 1.60 mg/dL (range, 1.0-2.6). The mean SCr of SKT patients was 1.59 +/- 0.63 mg/dL and of DKT, 1.62 +/- 0.48 mg/dL. Ten patients had delayed graft function and 11 had biopsy proven acute tubular necrosis. Seven (24%) patients had rejection (grade 3 Banff update '05, type IA; 4, type 2A); 6 responded to antirejection; 1 graft was lost at 7 months due to chronic rejection. Three (10.3%) patients were lost, 1 each due to AMI, sepsis, and CMV disease. In the circumstances of organ shortage, DDOT with expanded criteria donor is a feasible option.

  14. The effect of World Blood Donor Day on digital information seeking and donor recruitment.

    Science.gov (United States)

    Kranenburg, Floris J; Kreuger, Aukje L; Arbous, M Sesmu; Laeijendecker, Daphne; van Kraaij, Marian G J

    2017-10-01

    The purpose of World Blood Donor Day (WBDD) is to raise awareness for the importance of blood donation. The aim of this study was to quantify the impact of WBDD on digital information seeking and donor recruitment. Google Trends data were used to quantify seeking behavior on "blood donation" and "blood donor." Differences in relative search volume (RSV) between the 3 weeks surrounding WBDD and the rest of the year were calculated. Second, mean differences in RSV were compared to assess the additional effect of hosting using translated search terms. Third, we compared the period around WBDD with the control period regarding page views of the Sanquin website and Facebook likes and number of newly registered donors in 2016. The mean RSV for "blood donation" in the period of interest was 78.6, compared to 72.1 in the control period (difference, 6.5; 95% confidence interval [95% CI], 1.2-11.8). For "blood donor" this was 78.9 compared to 65.9 (difference, 12.9; 95% CI, 8.1-17.8). We found no additional effect of hosting. In the period of interest, the website of Sanquin was visited 6862 times a day and 4293 times in the control period (difference, 2569; 95% CI, 1687-3451). In June 2016, 54.6% (95% CI, 53.0-56.2) more new donors were registered compared to the control period. An international campaign like WBDD raises the awareness of blood donation and is effective in convincing people to register as blood donors. © 2017 AABB.

  15. Active Donor Management During the Hospital Phase of Care Is Associated with More Organs Transplanted per Donor.

    Science.gov (United States)

    Patel, Madhukar S; De La Cruz, Salvador; Sally, Mitchell B; Groat, Tahnee; Malinoski, Darren J

    2017-10-01

    Meeting donor management goals when caring for potential organ donors has been associated with more organs transplanted per donor (OTPD). Concern persists, however, as to whether this indicates that younger/healthier donors are more likely to meet donor management goals or whether active management affects outcomes. A prospective observational study of all standard criteria donors was conducted by 10 organ procurement organizations across United Network for Organ Sharing Regions 4, 5, and 6. Donor management goals representing normal critical care end points were measured at 2 time points: when a catastrophic brain injury was recognized and a referral was made to the organ procurement organization by the DH; and after brain death was declared and authorization for organ donation was obtained. Donor management goals Bundle "met" was defined as achieving any 7 of 9 end points. A positive Bundle status change was defined as not meeting the Bundle at referral and subsequently achieving it at authorization. The primary outcomes measure was having ≥4 OTPD. Data were collected for 1,398 standard criteria donors. Of the 1,166 (83%) who did not meet the Bundle at referral, only 254 (22%) had a positive Bundle status change. On adjusted analysis, positive Bundle status change increased the odds of achieving ≥4 OTPD significantly (odds ratio 2.04; 95% CI 1.49 to 2.81; p management goal Bundle status change during donor hospital management is associated with a 2-fold increase in achieving ≥4 OTPD. Active critical care management of the potential organ donor, as evidenced by improvement in routinely measured critical care end points can be a means by which to substantially increase the number of organs available for transplantation. Published by Elsevier Inc.

  16. Polyfluorophore Excimers and Exciplexes as FRET Donors in DNA

    Science.gov (United States)

    Teo, Yin Nah; Kool, Eric T.

    2009-01-01

    We describe studies aimed at testing whether oligomeric exciplex- and excimer fluorophores conjugated to DNA have the potential to act as donors for energy transfer by the Förster mechanism. Oligodeoxyfluorosides (ODFs) are composed of stacked, electronically interacting fluorophores replacing the bases on a DNA scaffold. The monomer chromophores in the twenty tetramer-length ODFs studied here include pyrene (Y), benzopyrene (B), perylene (E), dimethylaminostilbene (D), and a nonfluorescent spacer (S); these are conjugated in varied combinations at the 3’ end of a 14mer DNA probe sequence. In the absence of an acceptor chromophore, many of the ODF-DNAs show broad, unstructured long-wavelength emission peaks characteristic of excimer and exciplex excited states, similar to what has been observed for unconjugated ODFs. Although such delocalized excited states have been widely studied, we know of no prior report of their use in FRET. We tested the ability of the twenty ODFs to donate energy to Cy5 and TAMRA dyes conjugated to a complementary strand of DNA, with these acceptors oriented either at the near or far end of the ODF-conjugated probes. Results showed that a number of the ODF fluorophores exhibited relatively efficient energy transfer characteristic of the Förster mechanism, as judged by drops in donor emission quantum yield and fluorescence lifetime, accompanied by increases in intensity of acceptor emission bands. Excimer/exciplex bands in the donors were selectively quenched while shorter-wavelength monomer emission stayed relatively constant, consistent with the notion that the delocalized excited states, rather than individual fluorophores, are the donors. Interestingly, only specific sequences of ODFs were able to act as donors, while others did not, even though their emission wavelengths were similar. The new FRET donors possess large Stokes shifts, which can be beneficial for multiple applications. In addition, all ODFs can be excited at a single

  17. The prevalence of malaria parasitaemia in blood donors in a Nigerian teaching hospital.

    Science.gov (United States)

    Okocha, E C; Ibeh, C C; Ele, P U; Ibeh, N C

    2005-03-01

    The present study was undertaken to assess the prevalence of malaria parasitaemia among blood donors and to determine the possible risk of transmission of malaria parasite to recipients of blood in Nnamdi Azikiwe University Teaching Hospital, Nnewi, Anambra State. Four hundred and forty-four subjects were selected randomly and EDTA added blood was collected for screening malaria parasites using Giemsa stain. The data were subjected to chi2 analysis. Prevalence of malaria was 30.2% among blood donors and showed bimodal distribution with significant variation in different months. Due to high prevalence of asymptomatic malaria parasitaemia in this region, all blood samples should be screened for malaria parasites (post-donor screening) and administered with a curative dose of antimalarials prophylactically to all patients transfused with malaria parasite positive blood.

  18. [Lack of donor organs as an argument for living donors?].

    Science.gov (United States)

    Kirste, G

    2010-09-01

    In Germany more than 12,000 patients are presently waiting for an organ donation. Living donation makes sense for the long waiting time for a kidney, but it is not a permanent solution for the lack of organ donations. In the future topics which should be discussed are intensified public relations, a better family care and the allocation of rights and duties at the German coordinating agency. For all the prospects of success after a living donation the high standards of quality and security, which are targeted by the German donor organization in recipient protection, responsible evaluation of the expanded donor criteria and immunosuppressive therapy are all in favor of post-mortem organ donation. For all the phenomenal chance of success the priority of the post-mortem organ donation is regulated by law. The living donation remains an individual decision of the donor and the personal situation of life.

  19. The relationship between PMI (manA) gene expression and optimal selection pressure in Indica rice transformation.

    Science.gov (United States)

    Gui, Huaping; Li, Xia; Liu, Yubo; Han, Kai; Li, Xianggan

    2014-07-01

    An efficient mannose selection system was established for transformation of Indica cultivar IR58025B . Different selection pressures were required to achieve optimum transformation frequency for different PMI selectable marker cassettes. This study was conducted to establish an efficient transformation system for Indica rice, cultivar IR58025B. Four combinations of two promoters, rice Actin 1 and maize Ubiquitin 1, and two manA genes, native gene from E. coli (PMI-01) and synthetic maize codon-optimized gene (PMI-09) were compared under various concentrations of mannose. Different selection pressures were required for different gene cassettes to achieve corresponding optimum transformation frequency (TF). Higher TFs as 54 and 53% were obtained when 5 g/L mannose was used for selection of prActin-PMI-01 cassette and 7.5 g/L mannose used for selection of prActin-PMI-09, respectively. TFs as 67 and 56% were obtained when 7.5 and 15 g/L mannose were used for selection of prUbi-PMI-01 and prUbi-PMI-09, respectively. We conclude that higher TFs can be achieved for different gene cassettes when an optimum selection pressure is applied. By investigating the PMI expression level in transgenic calli and leaves, we found there was a significant positive correlation between the protein expression level and the optimal selection pressure. Higher optimal selection pressure is required for those constructs which confer higher expression of PMI protein. The single copy rate of those transgenic events for prActin-PMI-01 cassette is lower than that for other three cassettes. We speculate some of low copy events with low protein expression levels might not have been able to survive in the mannose selection.

  20. Chiral stationary phase optimized selectivity liquid chromatography: A strategy for the separation of chiral isomers.

    Science.gov (United States)

    Hegade, Ravindra Suryakant; De Beer, Maarten; Lynen, Frederic

    2017-09-15

    Chiral Stationary-Phase Optimized Selectivity Liquid Chromatography (SOSLC) is proposed as a tool to optimally separate mixtures of enantiomers on a set of commercially available coupled chiral columns. This approach allows for the prediction of the separation profiles on any possible combination of the chiral stationary phases based on a limited number of preliminary analyses, followed by automated selection of the optimal column combination. Both the isocratic and gradient SOSLC approach were implemented for prediction of the retention times for a mixture of 4 chiral pairs on all possible combinations of the 5 commercial chiral columns. Predictions in isocratic and gradient mode were performed with a commercially available and with an in-house developed Microsoft visual basic algorithm, respectively. Optimal predictions in the isocratic mode required the coupling of 4 columns whereby relative deviations between the predicted and experimental retention times ranged between 2 and 7%. Gradient predictions led to the coupling of 3 chiral columns allowing baseline separation of all solutes, whereby differences between predictions and experiments ranged between 0 and 12%. The methodology is a novel tool allowing optimizing the separation of mixtures of optical isomers. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Donor cytomegalovirus status influences the outcome of allogeneic stem cell transplant: a study by the European group for blood and marrow transplantation.

    Science.gov (United States)

    Ljungman, Per; Brand, Ronald; Hoek, Jennifer; de la Camara, Rafael; Cordonnier, Catherine; Einsele, Hermann; Styczynski, Jan; Ward, Katherine N; Cesaro, Simone

    2014-08-15

    The use of a cytomegalovirus (CMV)-seronegative donor for a CMV-seronegative allogeneic hematopoietic stem cell transplant (HSCT) recipient is generally accepted. However, the importance of donor serostatus in CMV-seropositive patients is controversial. A total of 49 542 HSCT patients, 29 349 seropositive and 20 193 seronegative, were identified from the European Group for Blood and Marrow Transplantation database. Cox multivariate models were fitted to estimate the effect of donor CMV serological status on outcome. Seronegative patients receiving seropositive unrelated-donor grafts had decreased overall survival (hazard ratio [HR], 1.13; 95% confidence interval [CI], 1.06-1.21; P donors, whereas no difference was seen in patients receiving HLA-matched sibling grafts. Seropositive patients receiving grafts from seropositive unrelated donors had improved overall survival (HR, 0.92; 95% CI, .86-.98; P donors, if they had received myeloablative conditioning. This effect was absent when they received reduced-intensity conditioning. No effect was seen in patients grafted from HLA-identical sibling donors. The same association was found if the study was limited to patients receiving transplants from the year 2000 onward. We confirm the negative impact on overall survival if a CMV-seropositive unrelated donor is selected for a CMV-seronegative patient. For a CMV-seropositive patient, our data support selecting a CMV-seropositive donor if the patient receives a myeloablative conditioning regimen. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  2. Donor-derived aspergillosis from use of a solid organ recipient as a multiorgan donor.

    Science.gov (United States)

    Mueller, N J; Weisser, M; Fehr, T; Wüthrich, R P; Müllhaupt, B; Lehmann, R; Imhof, A; Aubert, J-D; Genoni, M; Kunz, R; Weber, M; Steiger, J

    2010-02-01

    The growing need for organs and the scarcity of donors has resulted in an increased use of extended criteria donors. We report a case where a recipient of a cardiac graft was used as an organ donor. Death of the recipient occurred 9 days after transplantation and was attributed to presumed cerebral hemorrhage, which post mortem was diagnosed as invasive aspergillosis of the brain. One recipient of a kidney transplant lost the graft due to infection with Aspergillus fumigatus, whereas prompt initiation of therapy successfully prevented disseminated aspergillosis in the other recipients. Despite the pressure to extend the use of organs by lowering the acceptance criteria, organs should only be accepted if the cause of death of the donors is unequivocally explained.

  3. Systems of donor transfer

    NARCIS (Netherlands)

    F.T. de Charro (Frank); J.E.M. Akveld (Hans); E. Hessing (Ellen)

    1993-01-01

    textabstractThe development of medical knowledge has resulted in a demand in society for donor organs, but the recruitment of donor organs for transplantation is difficult. This paper aims to provide some general insights into the complex interaction processes involved. A laissez-faire policy, in

  4. Adult-to-adult living donor liver transplantation

    OpenAIRE

    Shah, Shimul A; Levy, Gary A; Adcock, Lesley D; Gallagher, Gary; Grant, David R

    2006-01-01

    The present review outlines the principles of living donor liver transplantation, donor workup, procedure and outcomes. Living donation offers a solution to the growing gap between the need for liver transplants and the limited availability of deceased donor organs. With a multidisciplinary team focused on donor safety and experienced surgeons capable of performing complex resection/reconstruction procedures, donor morbidity is low and recipient outcomes are comparable with results of decease...

  5. A multi-fidelity analysis selection method using a constrained discrete optimization formulation

    Science.gov (United States)

    Stults, Ian C.

    The purpose of this research is to develop a method for selecting the fidelity of contributing analyses in computer simulations. Model uncertainty is a significant component of result validity, yet it is neglected in most conceptual design studies. When it is considered, it is done so in only a limited fashion, and therefore brings the validity of selections made based on these results into question. Neglecting model uncertainty can potentially cause costly redesigns of concepts later in the design process or can even cause program cancellation. Rather than neglecting it, if one were to instead not only realize the model uncertainty in tools being used but also use this information to select the tools for a contributing analysis, studies could be conducted more efficiently and trust in results could be quantified. Methods for performing this are generally not rigorous or traceable, and in many cases the improvement and additional time spent performing enhanced calculations are washed out by less accurate calculations performed downstream. The intent of this research is to resolve this issue by providing a method which will minimize the amount of time spent conducting computer simulations while meeting accuracy and concept resolution requirements for results. In many conceptual design programs, only limited data is available for quantifying model uncertainty. Because of this data sparsity, traditional probabilistic means for quantifying uncertainty should be reconsidered. This research proposes to instead quantify model uncertainty using an evidence theory formulation (also referred to as Dempster-Shafer theory) in lieu of the traditional probabilistic approach. Specific weaknesses in using evidence theory for quantifying model uncertainty are identified and addressed for the purposes of the Fidelity Selection Problem. A series of experiments was conducted to address these weaknesses using n-dimensional optimization test functions. These experiments found that model

  6. Kidney transplant outcomes from older deceased donors

    DEFF Research Database (Denmark)

    Pippias, Maria; Jager, Kitty J; Caskey, Fergus

    2018-01-01

    As the median age of deceased kidney donors rises, updated knowledge of transplant outcomes from older deceased donors in differing donor-recipient age groups is required. Using ERA-EDTA Registry data we determined survival outcomes of kidney allografts donated from the same older deceased donor...

  7. Liver Transplantation: Evolving Patient Selection Criteria

    Directory of Open Access Journals (Sweden)

    Andy S Yu

    2001-01-01

    Full Text Available The widespread recognition of the success of liver transplantation as a treatment for most types of acute and chronic liver failure has led to increased referrals for transplantation in the setting of a relatively fixed supply of cadaver donor organs. These events have led to a marked lengthening of the waiting time for liver transplantation, resulting in increased deaths of those on the waiting list and sicker patients undergoing transplantation. Nearly 5000 liver transplantations were performed in the United States in 2000, while the waiting list grew to over 17,000 patients. The mounting disparity between the number of liver transplant candidates and the limited supply of donor organs has led to reassessment of the selection and listing criteria for liver transplantation, as well as revision of organ allocation and distribution policies for cadaver livers. The development of minimal listing criteria for patients with chronic liver disease based on a specific definition for decompensation of cirrhosis has facilitated the more uniform listing of patients at individual centres across the United States. The United Network for Organ Sharing, under pressure from transplant professionals, patient advocacy groups and the federal government, has continuously revised allocation and distribution policies based on the ethical principles of justice for the individual patient versus optimal utility of the limited organ supply available annually. Beginning in 2002, it is likely that the Model for End-stage Liver Disease (MELD score will be implemented to determine disease severity and direct donor organs to the sickest patients rather than to those with the longest waiting times.

  8. A concurrent optimization model for supplier selection with fuzzy quality loss

    International Nuclear Information System (INIS)

    Rosyidi, C.; Murtisari, R.; Jauhari, W.

    2017-01-01

    The purpose of this research is to develop a concurrent supplier selection model to minimize the purchasing cost and fuzzy quality loss considering process capability and assembled product specification. Design/methodology/approach: This research integrates fuzzy quality loss in the model to concurrently solve the decision making in detailed design stage and manufacturing stage. Findings: The resulted model can be used to concurrently select the optimal supplier and determine the tolerance of the components. The model balances the purchasing cost and fuzzy quality loss. Originality/value: An assembled product consists of many components which must be purchased from the suppliers. Fuzzy quality loss is integrated in the supplier selection model to allow the vagueness in final assembly by grouping the assembly into several grades according to the resulted assembly tolerance.

  9. A concurrent optimization model for supplier selection with fuzzy quality loss

    Energy Technology Data Exchange (ETDEWEB)

    Rosyidi, C.; Murtisari, R.; Jauhari, W.

    2017-07-01

    The purpose of this research is to develop a concurrent supplier selection model to minimize the purchasing cost and fuzzy quality loss considering process capability and assembled product specification. Design/methodology/approach: This research integrates fuzzy quality loss in the model to concurrently solve the decision making in detailed design stage and manufacturing stage. Findings: The resulted model can be used to concurrently select the optimal supplier and determine the tolerance of the components. The model balances the purchasing cost and fuzzy quality loss. Originality/value: An assembled product consists of many components which must be purchased from the suppliers. Fuzzy quality loss is integrated in the supplier selection model to allow the vagueness in final assembly by grouping the assembly into several grades according to the resulted assembly tolerance.

  10. Recruitment of aged donor heart with pharmacological stress echo. A case report

    Directory of Open Access Journals (Sweden)

    Bombardini Tonino

    2006-01-01

    the first time stress echo was successfully used in the critical theater of screening potential donor hearts. This method is enormously more feasible, less expensive, and more environmentally sustainable than any possible alternative strategy based on stress scintigraphy perfusion imaging or coronary angiography. The selection of hearts "too good to die" on the basis of bedside resting and stress echo can be a critical way to solve the mismatch between donor need and supply.

  11. An improved chaotic fruit fly optimization based on a mutation strategy for simultaneous feature selection and parameter optimization for SVM and its applications.

    Science.gov (United States)

    Ye, Fei; Lou, Xin Yuan; Sun, Lin Fu

    2017-01-01

    This paper proposes a new support vector machine (SVM) optimization scheme based on an improved chaotic fly optimization algorithm (FOA) with a mutation strategy to simultaneously perform parameter setting turning for the SVM and feature selection. In the improved FOA, the chaotic particle initializes the fruit fly swarm location and replaces the expression of distance for the fruit fly to find the food source. However, the proposed mutation strategy uses two distinct generative mechanisms for new food sources at the osphresis phase, allowing the algorithm procedure to search for the optimal solution in both the whole solution space and within the local solution space containing the fruit fly swarm location. In an evaluation based on a group of ten benchmark problems, the proposed algorithm's performance is compared with that of other well-known algorithms, and the results support the superiority of the proposed algorithm. Moreover, this algorithm is successfully applied in a SVM to perform both parameter setting turning for the SVM and feature selection to solve real-world classification problems. This method is called chaotic fruit fly optimization algorithm (CIFOA)-SVM and has been shown to be a more robust and effective optimization method than other well-known methods, particularly in terms of solving the medical diagnosis problem and the credit card problem.

  12. TH-EF-BRB-05: 4pi Non-Coplanar IMRT Beam Angle Selection by Convex Optimization with Group Sparsity Penalty

    International Nuclear Information System (INIS)

    O’Connor, D; Nguyen, D; Voronenko, Y; Yin, W; Sheng, K

    2016-01-01

    Purpose: Integrated beam orientation and fluence map optimization is expected to be the foundation of robust automated planning but existing heuristic methods do not promise global optimality. We aim to develop a new method for beam angle selection in 4π non-coplanar IMRT systems based on solving (globally) a single convex optimization problem, and to demonstrate the effectiveness of the method by comparison with a state of the art column generation method for 4π beam angle selection. Methods: The beam angle selection problem is formulated as a large scale convex fluence map optimization problem with an additional group sparsity term that encourages most candidate beams to be inactive. The optimization problem is solved using an accelerated first-order method, the Fast Iterative Shrinkage-Thresholding Algorithm (FISTA). The beam angle selection and fluence map optimization algorithm is used to create non-coplanar 4π treatment plans for several cases (including head and neck, lung, and prostate cases) and the resulting treatment plans are compared with 4π treatment plans created using the column generation algorithm. Results: In our experiments the treatment plans created using the group sparsity method meet or exceed the dosimetric quality of plans created using the column generation algorithm, which was shown superior to clinical plans. Moreover, the group sparsity approach converges in about 3 minutes in these cases, as compared with runtimes of a few hours for the column generation method. Conclusion: This work demonstrates the first non-greedy approach to non-coplanar beam angle selection, based on convex optimization, for 4π IMRT systems. The method given here improves both treatment plan quality and runtime as compared with a state of the art column generation algorithm. When the group sparsity term is set to zero, we obtain an excellent method for fluence map optimization, useful when beam angles have already been selected. NIH R43CA183390, NIH R01CA

  13. Global blending optimization of laminated composites with discrete material candidate selection and thickness variation

    DEFF Research Database (Denmark)

    Sørensen, Søren N.; Stolpe, Mathias

    2015-01-01

    rate. The capabilities of the method and the effect of active versus inactive manufacturing constraints are demonstrated on several numerical examples of limited size, involving at most 320 binary variables. Most examples are solved to guaranteed global optimality and may constitute benchmark examples...... but is, however, convex in the original mixed binary nested form. Convexity is the foremost important property of optimization problems, and the proposed method can guarantee the global or near-global optimal solution; unlike most topology optimization methods. The material selection is limited...... for popular topology optimization methods and heuristics based on solving sequences of non-convex problems. The results will among others demonstrate that the difficulty of the posed problem is highly dependent upon the composition of the constitutive properties of the material candidates....

  14. Utilization of organs from donors after circulatory death for vascularized pancreas and islet of Langerhans transplantation : recommendations from an expert group

    NARCIS (Netherlands)

    Berney, Thierry; Boffa, Catherine; Augustine, Titus; Badet, Lionel; de Koning, Eelco; Pratschke, Johann; Socci, Carlo; Friend, Peter

    2015-01-01

    Donation after circulatory death (DCD) donors are increasingly being used as a source of pancreas allografts for vascularized organ and islet transplantation. We provide practice guidelines aiming to increase DCD pancreas utilization. We review risk assessment and donor selection criteria. We report

  15. Utilization of organs from donors after circulatory death for vascularized pancreas and islet of Langerhans transplantation: recommendations from an expert group.

    Science.gov (United States)

    Berney, Thierry; Boffa, Catherine; Augustine, Titus; Badet, Lionel; de Koning, Eelco; Pratschke, Johann; Socci, Carlo; Friend, Peter

    2016-07-01

    Donation after circulatory death (DCD) donors are increasingly being used as a source of pancreas allografts for vascularized organ and islet transplantation. We provide practice guidelines aiming to increase DCD pancreas utilization. We review risk assessment and donor selection criteria. We report suggested factors in donor and recipient clinical management and provide an overview of the activities and outcomes of vascularized pancreas and islet transplantation. © 2015 Steunstichting ESOT.

  16. Contrast based band selection for optimized weathered oil detection in hyperspectral images

    Science.gov (United States)

    Levaux, Florian; Bostater, Charles R., Jr.; Neyt, Xavier

    2012-09-01

    Hyperspectral imagery offers unique benefits for detection of land and water features due to the information contained in reflectance signatures such as the bi-directional reflectance distribution function or BRDF. The reflectance signature directly shows the relative absorption and backscattering features of targets. These features can be very useful in shoreline monitoring or surveillance applications, for example to detect weathered oil. In real-time detection applications, processing of hyperspectral data can be an important tool and Optimal band selection is thus important in real time applications in order to select the essential bands using the absorption and backscatter information. In the present paper, band selection is based upon the optimization of target detection using contrast algorithms. The common definition of the contrast (using only one band out of all possible combinations available within a hyperspectral image) is generalized in order to consider all the possible combinations of wavelength dependent contrasts using hyperspectral images. The inflection (defined here as an approximation of the second derivative) is also used in order to enhance the variations in the reflectance spectra as well as in the contrast spectrua in order to assist in optimal band selection. The results of the selection in term of target detection (false alarms and missed detection) are also compared with a previous method to perform feature detection, namely the matched filter. In this paper, imagery is acquired using a pushbroom hyperspectral sensor mounted at the bow of a small vessel. The sensor is mechanically rotated using an optical rotation stage. This opto-mechanical scanning system produces hyperspectral images with pixel sizes on the order of mm to cm scales, depending upon the distance between the sensor and the shoreline being monitored. The motion of the platform during the acquisition induces distortions in the collected HSI imagery. It is therefore

  17. Trends in organ donor management: 2002 to 2012.

    Science.gov (United States)

    Callahan, Devon S; Kim, Dennis; Bricker, Scott; Neville, Angela; Putnam, Brant; Smith, Jennifer; Bongard, Frederic; Plurad, David

    2014-10-01

    Refinements in donor management have resulted in increased numbers and quality of grafts after neurologic death. We hypothesize that the increased use of hormone replacement therapy (HRT) has been accompanied by improved outcomes over time. Using the Organ Procurement and Transplant Network donor database, all brain-dead donors procured from July 1, 2001 to June 30, 2012 were studied. Hormone replacement therapy was identified by an infusion of thyroid hormone. An expanded criteria donor was defined as age 60 years or older. Incidence of HRT administration and number of donors and organs recovered were calculated. Using the Organ Procurement and Transplant Network thoracic recipient database transplant list, wait times were examined. There were 74,180 brain-dead donors studied. Hormone replacement therapy use increased substantially from 25.6% to 72.3% of donors. However, mean number of organs procured per donor remained static (3.51 to 3.50; p = 0.083), and the rate of high-yield donors decreased (46.4% to 43.1%; p donors decreased (42.1% to 33.9%; p donors (22.1% to 26%). Despite this, there has been an increase in the raw number of donors (20,558 to 24,308; p organs (5,857 to 6,945; p organs per traumatic brain injury donor (4.02 to 4.12; p = 0.002) and a decrease in days on the waiting list (462.2 to 170.4 days; p donors has been accompanied by increased organ availability overall. Potential mechanisms might include successful conversion of previously unacceptable donors and improved recovery in certain subsets of donors. Copyright © 2014 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

  18. Causes of discontinuity of blood donation among donors in Shiraz, Iran: cross-sectional study

    Directory of Open Access Journals (Sweden)

    Leila Kasraian

    Full Text Available CONTEXT AND OBJECTIVE: The adequacy of blood depends on blood donation rates and numbers of blood donors. To prepare adequate blood supplies, it is essential to investigate the barriers and factors that stop individuals from donating. This study aimed to identify the causes of lapsed donation at our center. DESIGN AND SETTING: Cross-sectional study of volunteer blood donors in Shiraz, Iran. METHODS: We selected 850 donors who had donated between January 1, 2005 and June 1, 2005, but had not donated again by June 2008. The participants were recruited by letter and telephone, and were interviewed using a specially designed questionnaire that contained items on demographic characteristics, donor motivations and reasons for not returning to donate. We used the chi-square test to identify associations between lapsed donor characteristics and reasons for declining to donate. RESULTS: The greatest motivation for donation was altruism. The most frequent reasons for lapsed donation were lack of time because of work and self-exclusion for medical reasons. Among first-time donors, the most frequent reasons were unsuitability for donation and lack of time. CONCLUSIONS: The reasons for not returning to donate are varied and may correlate with demographic characteristics. In this study, the main reason for not returning was lack of time. Changing donation hours so that donors can donate after work, providing mobile teams at workplaces, and shortening the duration of the donation process may help increase repeat donation rates.

  19. A feasibility study: Selection of a personalized radiotherapy fractionation schedule using spatiotemporal optimization

    International Nuclear Information System (INIS)

    Kim, Minsun; Stewart, Robert D.; Phillips, Mark H.

    2015-01-01

    Purpose: To investigate the impact of using spatiotemporal optimization, i.e., intensity-modulated spatial optimization followed by fractionation schedule optimization, to select the patient-specific fractionation schedule that maximizes the tumor biologically equivalent dose (BED) under dose constraints for multiple organs-at-risk (OARs). Methods: Spatiotemporal optimization was applied to a variety of lung tumors in a phantom geometry using a range of tumor sizes and locations. The optimal fractionation schedule for a patient using the linear-quadratic cell survival model depends on the tumor and OAR sensitivity to fraction size (α/β), the effective tumor doubling time (T d ), and the size and location of tumor target relative to one or more OARs (dose distribution). The authors used a spatiotemporal optimization method to identify the optimal number of fractions N that maximizes the 3D tumor BED distribution for 16 lung phantom cases. The selection of the optimal fractionation schedule used equivalent (30-fraction) OAR constraints for the heart (D mean ≤ 45 Gy), lungs (D mean ≤ 20 Gy), cord (D max ≤ 45 Gy), esophagus (D max ≤ 63 Gy), and unspecified tissues (D 05 ≤ 60 Gy). To assess plan quality, the authors compared the minimum, mean, maximum, and D 95 of tumor BED, as well as the equivalent uniform dose (EUD) for optimized plans to conventional intensity-modulated radiation therapy plans prescribing 60 Gy in 30 fractions. A sensitivity analysis was performed to assess the effects of T d (3–100 days), tumor lag-time (T k = 0–10 days), and the size of tumors on optimal fractionation schedule. Results: Using an α/β ratio of 10 Gy, the average values of tumor max, min, mean BED, and D 95 were up to 19%, 21%, 20%, and 19% larger than those from conventional prescription, depending on T d and T k used. Tumor EUD was up to 17% larger than the conventional prescription. For fast proliferating tumors with T d less than 10 days, there was no

  20. Changes in pre- and post-donation platelet function in plateletpheresis donors.

    Science.gov (United States)

    Zhou, Q; Yu, X; Cai, Y; Liu, L

    2017-11-01

    This study aimed to investigate the changes of platelet (PLT) function and coagulation time before and after plateletpheresis donation. The healthy donors were divided into four groups according to the annual number of plateletpheresis donation: 20 times group, 15 times group, 10 times group and 5 times group. The healthy non-blood donors were selected as controls. The donation interval was 14 days. The blood samples were collected before plateletpheresis donation and after 30min, 7 d, and 14 d of donation for determination of coagulation time, PLT function, plasma protein, serum iron and blood routine change. After 30min of plateletpheresis donation, the PLT function decreased and the coagulation time was prolonged. However, PLT function recovered to the pre-collection after 7 d of plateletpheresis donation and coagulation time recovered to the pre-collection after 14 d of plateletpheresis donation. Additionally, there was no difference regarding blood coagulation time and PLT function among blood donors and controls. The plasma protein and serum iron levels in 20 times and 15 times groups were within the normal reference range. The frequency of plateletpheresis donation will not affect PLT function, coagulation time, plasma protein and serum iron in donors. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  1. Spectral Quantitative Analysis Model with Combining Wavelength Selection and Topology Structure Optimization

    Directory of Open Access Journals (Sweden)

    Qian Wang

    2016-01-01

    Full Text Available Spectroscopy is an efficient and widely used quantitative analysis method. In this paper, a spectral quantitative analysis model with combining wavelength selection and topology structure optimization is proposed. For the proposed method, backpropagation neural network is adopted for building the component prediction model, and the simultaneousness optimization of the wavelength selection and the topology structure of neural network is realized by nonlinear adaptive evolutionary programming (NAEP. The hybrid chromosome in binary scheme of NAEP has three parts. The first part represents the topology structure of neural network, the second part represents the selection of wavelengths in the spectral data, and the third part represents the parameters of mutation of NAEP. Two real flue gas datasets are used in the experiments. In order to present the effectiveness of the methods, the partial least squares with full spectrum, the partial least squares combined with genetic algorithm, the uninformative variable elimination method, the backpropagation neural network with full spectrum, the backpropagation neural network combined with genetic algorithm, and the proposed method are performed for building the component prediction model. Experimental results verify that the proposed method has the ability to predict more accurately and robustly as a practical spectral analysis tool.

  2. Living related donor liver transplantation.

    Science.gov (United States)

    Chen, C L; Chen, Y S; Liu, P P; Chiang, Y C; Cheng, Y F; Huang, T L; Eng, H L

    1997-10-01

    Living related liver transplantation (LRLT) has been developed in response to the paediatric organ donor shortage. According to the International Living Donor Registry, 521 transplants had been performed in 515 patients between December 8 1988 and January 19 1996 in 30 centres worldwide. The overall actuarial patient and graft survival rates were 82.7 and 80%, respectively. Between June 17 1994 and November 30 1996, the authors performed 11 LRLT at the Chung Gung Memorial Hospital. The living donors consisted of 10 mothers and one father. The mean graft weight was 303 g and the mean graft recipient weight ratio was 2.2%. Donor hepatectomy was performed without vascular inflow occlusion. The intra-operative blood loss ranged from 30 mL to 120 mL with an average of 61 mL, and blood transfusion was not required in all donors both intra-operatively and during the postoperative period. Underlying diseases of the recipients were biliary atresia (n = 10) and glycogen storage disease (n = 1). The mean graft cold ischaemia time was 106 min, the mean second warm ischaemia time was 51 min and the mean interval between portal and arterial reperfusion was 81 min. The initial LRLT results were promising with all donors having been discharged without complication. The recipients experienced a few complications, all of which were manageable with early intervention. All 11 recipients are alive and well. These are encouraging results and the authors hope to expand the use of live donors for liver transplantation to cope with demand.

  3. Correlation and clinical significance between glomerular filtration rate and age in living-related kidney donors

    International Nuclear Information System (INIS)

    Zhao Xiuyi; Shao Yahui; Wang Yanming; Zhang Aimin; Hao Junwen; Tian Jun; Sun Ben; Han Jiankui

    2010-01-01

    Objective: To quantitatively investigate the effect of age on the glomerular filtration rate (GFR) in living-related kidney donors. to analyze the clinical value and the dependence of GFR on age and to provide an objective basis for the selection of the living kidney donor. Methods: One hundred and sixty-one living-related kidney donors were divided into four age groups, namely 20-29 years (n=52), 30-39 years (n=44), 40-49 years (n=38) and ≥50 years (n=27). On the other hand, the total donors were divided into the groups older than 55 years (n=24) and younger than 55 years (n=137). To quantify GFR in all the subjects using the 99 Tc m -diethylenetriamine pentaacetic acid ( 99 Tc m -DTPA) renography according to standard procedure and to evaluate the effects of age on renal function. Results: The total GFR in living-related kidney donors was calculated as (89.55±12.87) ml·min -1 ·(1.73 m 2 ) -1 . The GFR in the first to the four age groups were (88.27±12.29) ml·min -1 ·(1.73 m 2 ) -1 , (91.85±14.51) ml·min -1 ·(1.73 m 2 ) -1 , (98.25±11.26) ml·min -1 ·(1.73 m 2 ) -1 and (88.24±13.20) ml·min -1 ·(1.73 m 2 ) -1 . The difference of GFR were not significant between the four age groups (F=2.09, P=0.10). The GFR in the donors older than 55 years and younger than 55 years were (88.57±13.14) ml·min -1 ·(1.73 m 2 ) -1 and (89.44±10.34) ml·min -1 ·(1.73 m 2 ) -1 , there no significant difference in GFR between the two groups (F=1.31, P=0.25). When relating GFR to age in all the living-related kidney donors, there was no significant correlation (r=-0.033, P=0.69). No serious complications occurred after living kidney transplantation, serum creatinine values and blood urea nitrogen recovered to the normal levels in a short period, hepatic and renal functions were normal. Conclusion: This study indicated that the GFR values were not correlated with the change of age in living-related kidney donors, and the results were helpful for the selection of living

  4. Importance of Donor Chondrocyte Viability for Osteochondral Allografts.

    Science.gov (United States)

    Cook, James L; Stannard, James P; Stoker, Aaron M; Bozynski, Chantelle C; Kuroki, Keiichi; Cook, Cristi R; Pfeiffer, Ferris M

    2016-05-01

    chondrocytes with infiltration of fibroblasts from the surrounding recipient tissues. In situ polymerase chain reaction (fluorescence in situ hybridization [FISH]) assays were performed in an attempt to distinguish donor (male) cells from recipient (female) cells. Unfortunately, this technique was exceptionally difficult to perform on intact articular cartilage sections, and consistent, repeatable data could not be obtained from this testing. However, the data did support histologic and live-dead data, which strongly suggested that successful grafts retained viable donor (male) chondrocytes and unsuccessful grafts degraded and were replaced by fibrous tissue populated with recipient (female) fibroblasts. Viable chondrocytes in OCAs at the time of transplantation are primarily responsible for maintenance of donor articular cartilage health in the long term. Optimizing chondrocyte viability in all aspects of OCA transplantation-including procurement, processing, storage, transportation, and surgical implantation-needs to be a primary focus for OCA clinical use. © 2016 The Author(s).

  5. Long-term outcome of renal transplantation from octogenarian donors: A multicenter controlled study.

    Science.gov (United States)

    Ruggenenti, Piero; Silvestre, Cristina; Boschiero, Luigino; Rota, Giovanni; Furian, Lucrezia; Perna, Annalisa; Rossini, Giuseppe; Remuzzi, Giuseppe; Rigotti, Paolo

    2017-12-01

    To assess whether biopsy-guided selection of kidneys from very old brain-dead donors enables more successful transplantations, the authors of this multicenter, observational study compared graft survival between 37 recipients of 1 or 2 histologically evaluated kidneys from donors older than 80 years and 198 reference-recipients of non-histologically evaluated single grafts from donors aged 60 years and younger (transplantation period: 2006-2013 at 3 Italian centers). During a median (interquartile range) of 25 (13-42) months, 2 recipients (5.4%) and 10 reference-recipients (5.1%) required dialysis (crude and donor age- and sex-adjusted hazard ratio [95% confidence interval] 1.55 [0.34-7.12], P = .576 and 1.41 [0.10-19.54], P = .798, respectively). Shared frailty analyses confirmed similar outcomes in a 1:2 propensity score study comparing recipients with 74 reference-recipients matched by center, year, donor, and recipient sex and age. Serum creatinine was similar across groups during 84-month follow-up. Recipients had remarkably shorter waiting times than did reference-recipients and matched reference-recipients (7.5 [4.0-19.5] vs 36 [19-56] and 40 [24-56] months, respectively, P < .0001 for both comparisons). Mean (± SD) kidney donor risk index was 2.57 ± 0.32 in recipients vs 1.09 ± 0.24 and 1.14 ± 0.24 in reference-recipients and matched reference-recipients (P < .0001 for both comparisons). Adverse events were similar across groups. Biopsy-guided allocation of kidneys from octogenarian donors permits further expansion of the donor organ pool and faster access to a kidney transplant, without increasing the risk of premature graft failure. © 2017 The American Society of Transplantation and the American Society of Transplant Surgeons.

  6. Why search for a sperm donor online? The experiences of women searching for and contacting sperm donors on the internet.

    Science.gov (United States)

    Jadva, Vasanti; Freeman, Tabitha; Tranfield, Erika; Golombok, Susan

    2018-06-01

    Whilst studies have examined the experiences of women who use clinic donors, to date there has been limited research investigating women's motivations and experiences of searching for a sperm donor online. A total of 429 women looking for a sperm donor on Pride Angel (a website that facilitates contact between donors and recipients) completed an online survey. Fifty-eight percent (249) saw advantages of obtaining donated sperm online with the most common advantage reported as being able to connect with and meet the donor (n = 50 (24%)). A third (n = 157 (37%)) of the participants gave disadvantages, the most common reported was encountering 'dishonest donors' (n = 63 (40%)). Most recipients (n = 181 (61%)) wanted the donor to be 'just a donor' (i.e. to provide sperm and have no further contact). Whilst it was important for recipients to know the identity of the donor, some did not see this as important for the child and thus the level of information that parents have about the donor, and that which the child has, can differ. Finding a donor online blurs the distinction between categories of 'anonymous', 'known' and 'identity release' donations. Whilst the survey had a large sample size, the representativeness of the sample is not known.

  7. Evaluating Varied Label Designs for Use with Medical Devices: Optimized Labels Outperform Existing Labels in the Correct Selection of Devices and Time to Select.

    Directory of Open Access Journals (Sweden)

    Laura Bix

    Full Text Available Effective standardization of medical device labels requires objective study of varied designs. Insufficient empirical evidence exists regarding how practitioners utilize and view labeling.Measure the effect of graphic elements (boxing information, grouping information, symbol use and color-coding to optimize a label for comparison with those typical of commercial medical devices.Participants viewed 54 trials on a computer screen. Trials were comprised of two labels that were identical with regard to graphics, but differed in one aspect of information (e.g., one had latex, the other did not. Participants were instructed to select the label along a given criteria (e.g., latex containing as quickly as possible. Dependent variables were binary (correct selection and continuous (time to correct selection.Eighty-nine healthcare professionals were recruited at Association of Surgical Technologists (AST conferences, and using a targeted e-mail of AST members.Symbol presence, color coding and grouping critical pieces of information all significantly improved selection rates and sped time to correct selection (α = 0.05. Conversely, when critical information was graphically boxed, probability of correct selection and time to selection were impaired (α = 0.05. Subsequently, responses from trials containing optimal treatments (color coded, critical information grouped with symbols were compared to two labels created based on a review of those commercially available. Optimal labels yielded a significant positive benefit regarding the probability of correct choice ((P<0.0001 LSM; UCL, LCL: 97.3%; 98.4%, 95.5%, as compared to the two labels we created based on commercial designs (92.0%; 94.7%, 87.9% and 89.8%; 93.0%, 85.3% and time to selection.Our study provides data regarding design factors, namely: color coding, symbol use and grouping of critical information that can be used to significantly enhance the performance of medical device labels.

  8. Phylogenetic analysis of TCE-dechlorinating consortia enriched on a variety of electron donors.

    Science.gov (United States)

    Freeborn, Ryan A; West, Kimberlee A; Bhupathiraju, Vishvesh K; Chauhan, Sadhana; Rahm, Brian G; Richardson, Ruth E; Alvarez-Cohen, Lisa

    2005-11-01

    Two rapidly fermented electron donors, lactate and methanol, and two slowly fermented electron donors, propionate and butyrate, were selected for enrichment studies to evaluate the characteristics of anaerobic microbial consortia that reductively dechlorinate TCE to ethene. Each electron donor enrichment subculture demonstrated the ability to dechlorinate TCE to ethene through several serial transfers. Microbial community analyses based upon 16S rDNA, including terminal restriction fragment length polymorphism (T-RFLP) and clone library/sequencing, were performed to assess major changes in microbial community structure associated with electron donors capable of stimulating reductive dechlorination. Results demonstrated that five phylogenic subgroups or genera of bacteria were present in all consortia, including Dehalococcoides sp., low G+C Gram-positives (mostly Clostridium and Eubacterium sp.), Bacteroides sp., Citrobacter sp., and delta Proteobacteria (mostly Desulfovibrio sp.). Phylogenetic association indicates that only minor shifts in the microbial community structure occurred between the four alternate electron donor enrichments and the parent consortium. Inconsistent detection of Dehalococcoides spp. in clone libraries and T-RFLP of enrichment subcultures was resolved using quantitative polymerase chain reaction (Q-PCR). Q-PCR with primers specific to Dehalococcoides 16S rDNA resulted in positive detection of this species in all enrichments. Our results suggest that TCE-dechlorinating consortia can be stably maintained on a variety of electron donors and that quantities of Dehalococcoides cells detected with Dehalococcoides specific 16S rDNA primer/probe sets do not necessarily correlate well with solvent degradation rates.

  9. A note on “An alternative multiple attribute decision making methodology for solving optimal facility layout design selection problems”

    OpenAIRE

    R. Venkata Rao

    2012-01-01

    A paper published by Maniya and Bhatt (2011) (An alternative multiple attribute decision making methodology for solving optimal facility layout design selection problems, Computers & Industrial Engineering, 61, 542-549) proposed an alternative multiple attribute decision making method named as “Preference Selection Index (PSI) method” for selection of an optimal facility layout design. The authors had claimed that the method was logical and more appropriate and the method gives directly the o...

  10. Prospective evaluation of 2% (w/v alcoholic chlorhexidine gluconate as an antiseptic agent for blood donor arm preparation

    Directory of Open Access Journals (Sweden)

    Sweta Shah

    2014-01-01

    Full Text Available Aim: A prospective study was undertaken to evaluate the use of 2% (w/v alcoholic chlorhexidine gluconate (2% AlcCHG in donor arm preparation, to monitor the contamination rate of blood products after the collection and to find incidence of transfusion associated bacteremia. Settings and Design: Optimal skin antisepsis of the phlebotomy site is essential to minimize the risk of contamination. Food and Drug Administration (FDA in India has recommended antisepsis with three-step regimen of spirit-10% povidone iodine-spirit for donor arm antisepsis, but not with chlorhexidine, which is recommended by many other authors. Material and Methods: A total of 795 donors were studied from July 2011 to January 2012. Spirit-10% povidone iodine-spirit was used for 398 donors and 2% AlcCHG was used for 397 donors with the two-step method for arm antisepsis. Swabs were collected before and after use of antiseptic agents for all the donors. All the blood products collected from donors with growth in post-antisepsis swabs were cultured. A total of 123 various blood products were cultured irrespective of the method and result of antisepsis was observed. A total of seven patients had mild transfusion reaction. The transfused blood products, blood and urine specimen of the patients who had transfusion reaction were also cultured. Results: Seven donors out of 398 donors had growth in post-antisepsis swab with spirit-10% povidone iodine-spirit protocol and three donors out of 397 donors had growth in post-antisepsis swab with 2% AlcCHG protocol. All blood products collected from donors who had growth in post-antisepsis swabs when cultured had no growth. There was no contamination of blood products. Conclusions: Two percent (w/v alcoholic chlorhexidine gluconate with two-step protocol can be used as an antiseptic agent for donor arm preparation without considerable cost difference. It is at par with spirit 10% povidone iodine spirit protocol as suggested by FDA in India

  11. Optimal Selection of AC Cables for Large Scale Offshore Wind Farms

    DEFF Research Database (Denmark)

    Hou, Peng; Hu, Weihao; Chen, Zhe

    2014-01-01

    The investment of large scale offshore wind farms is high in which the electrical system has a significant contribution to the total cost. As one of the key components, the cost of the connection cables affects the initial investment a lot. The development of cable manufacturing provides a vast...... and systematical way for the optimal selection of cables in large scale offshore wind farms....

  12. On the effect of nuclear bridge modes on donor-acceptor electronic coupling in donor-bridge-acceptor molecules

    International Nuclear Information System (INIS)

    Davis, Daly; Toroker, Maytal Caspary; Speiser, Shammai; Peskin, Uri

    2009-01-01

    We report a theoretical study of intra-molecular electronic coupling in a symmetric DBA (donor-bridge-acceptor) complex, in which a donor electronic site is coupled to an acceptor site by way of intervening orbitals of a molecular bridge unit. In the off-resonant (deep tunneling) regime of electronic transport, the lowest unoccupied molecular orbitals (MO's) of the DBA system are split into distinguishable donor/acceptor and bridge orbitals. The effect of geometrical changes at the bridge on the donor/acceptor electronic energy manifold is studied for local stretching and bending modes. It is demonstrated that the energy splitting in the manifold of donor/acceptor unoccupied MOs changes in response to such changes, as assumed in simple McConnell-type models. Limitations of the simple models are revealed where the electronic charging of the bridge orbitals correlates with increasing donor/acceptor orbital energy splitting only for stretching but not for bending bridge modes.

  13. Liver transplantation from maastricht category 2 non-heart-beating donors: a source to increase the donor pool?

    Science.gov (United States)

    Otero, A; Gómez-Gutiérrez, M; Suárez, F; Arnal, F; Fernández-García, A; Aguirrezabalaga, J; García-Buitrón, J; Alvarez, J; Máñez, R

    2004-04-01

    The demand for liver transplantation has increasingly exceeded the supply of cadaver donor organs. Non-heart-beating donors (NHBDs) may be an alternative to increase the cadaver donor pool. The outcome of 20 liver transplants from Maastricht category 2 NHBD was compared with that of 40 liver transplants from heart-beating donors (HBDs). After unsuccessful cardiopulmonary resuscitation (CPR), cardiopulmonary support with simultaneous application of chest and abdominal compression (CPS; n = 6) or cardiopulmonary bypass (CPB; n = 14) was used to maintain the donors. At a minimum follow-up of 2 years, actuarial patient and graft survival rates with livers from Maastricht category 2 NHBD were 80% and 55%, respectively. Transplantation of organs from these donors was associated with a significantly higher incidence of primary nonfunction, biliary complications, and more severe initial liver dysfunction compared with organs from HBDs. The graft survival rates was 83% for livers from NHBDs preserved with CPS and 42% in those maintained with CPB.

  14. Medium-Bandgap Small-Molecule Donors Compatible with Both Fullerene and Nonfullerene Acceptors.

    Science.gov (United States)

    Huo, Yong; Yan, Cenqi; Kan, Bin; Liu, Xiao-Fei; Chen, Li-Chuan; Hu, Chen-Xia; Lau, Tsz-Ki; Lu, Xinhui; Sun, Chun-Lin; Shao, Xiangfeng; Chen, Yongsheng; Zhan, Xiaowei; Zhang, Hao-Li

    2018-03-21

    Much effort has been devoted to the development of new donor materials for small-molecule organic solar cells due to their inherent advantages of well-defined molecular weight, easy purification, and good reproducibility in photovoltaic performance. Herein, we report two small-molecule donors that are compatible with both fullerene and nonfullerene acceptors. Both molecules consist of an (E)-1,2-di(thiophen-2-yl)ethane-substituted (TVT-substituted) benzo[1,2-b:4,5-b']dithiophene (BDT) as the central unit, and two rhodanine units as the terminal electron-withdrawing groups. The central units are modified with either alkyl side chains (DRBDT-TVT) or alkylthio side chains (DRBDT-STVT). Both molecules exhibit a medium bandgap with complementary absorption and proper energy level offset with typical acceptors like PC 71 BM and IDIC. The optimized devices show a decent power conversion efficiency (PCE) of 6.87% for small-molecule organic solar cells and 6.63% for nonfullerene all small-molecule organic solar cells. Our results reveal that rationally designed medium-bandgap small-molecule donors can be applied in high-performance small-molecule organic solar cells with different types of acceptors.

  15. Avoiding ICU Admission by Using a Fast-Track Protocol Is Safe in Selected Adult-to-Adult Live Donor Liver Transplant Recipients

    Directory of Open Access Journals (Sweden)

    Juan Echeverri, MD

    2017-10-01

    Full Text Available Background. We evaluated patient characteristics of live donor liver transplant (LDLT recipients undergoing a fast-track protocol without intensive care unit (ICU admission versus LDLT patients receiving posttransplant ICU care. Methods. Of the 153 LDLT recipients, 46 patients were included in our fast-track protocol without ICU admission. Both, fast-tracked patients and ICU-admitted patients were compared regarding donor and patient characteristics, perioperative characteristics, and postoperative outcomes and complications. In a subgroup analysis, we compared fast-tracked patients with patients who were admitted in the ICU for less than 24 hours. Results. Fast-tracked versus ICU patients had a lower model for end-stage liver disease score (13 ± 4 vs 18 ± 7; P < 0.0001, lower preoperative bilirubin levels (51 ± 50 μmol/L vs 119.4 ± 137.3 μmol/L; P < 0.001, required fewer units of packed red blood cells (1.7 ± 1.78 vs 4.4 ± 4; P < 0.0001, and less fresh-frozen plasma (2.7 ± 2 vs 5.8 ± 5; P < 0.0001 during transplantation. Regarding postoperative outcomes, fast-tracked patients presented fewer bacterial infections within 30 days (6.5% [3] vs 29% [28]; P = 0.002, no episodes of pneumonia (0% vs 11.3% [11]; P = 0.02, and less biliary complications within the first year (6% [3] vs 26% [25]; P = 0.001. Also, fast-tracked patients had a shorter posttransplant hospital stay (10.8 ± 5 vs 21.3 ± 29; P = 0.002. In the subgroup analysis, fast-tracked vs ICU patients admitted for less than 24 hours had lower requirements of packed red blood cells (1.7 ± 1.78 vs 3.9 ± 4; P = 0.001 and fresh-frozen plasma (2.7 ± 2 vs 5.8 ± 4.5; P = 0.0001. Conclusions. Fast-track of selected patients after LDLT is safe and feasible. An objective score to perioperatively select LDLT recipients amenable to fast track is yet to be determined.

  16. A Modified Protocol with Improved Detection Rate for Mis-Matched Donor HLA from Low Quantities of DNA in Urine Samples from Kidney Graft Recipients.

    Directory of Open Access Journals (Sweden)

    Janette Kwok

    Full Text Available Urine from kidney transplant recipient has proven to be a viable source for donor DNA. However, an optimized protocol would be required to determine mis-matched donor HLA specificities in view of the scarcity of DNA obtained in some cases.In this study, fresh early morning urine specimens were obtained from 155 kidney transplant recipients with known donor HLA phenotype. DNA was extracted and typing of HLA-A, B and DRB1 loci by polymerase chain reaction-specific sequence primers was performed using tailor-made condition according to the concentration of extracted DNA.HLA typing of DNA extracted from urine revealed both recipient and donor HLA phenotypes, allowing the deduction of the unknown donor HLA and hence the degree of HLA mis-match. By adopting the modified procedures, mis-matched donor HLA phenotypes were successfully deduced in all of 35 tested urine samples at DNA quantities spanning the range of 620-24,000 ng.This urine-based method offers a promising and reliable non-invasive means for the identification of mis-matched donor HLA antigens in kidney transplant recipients with unknown donor HLA phenotype or otherwise inadequate donor information.

  17. Epidemiological trends of HIV-1 infection in blood donors from Catalonia, Spain (2005-2014).

    Science.gov (United States)

    Bes, Marta; Piron, Maria; Casamitjana, Natàlia; Gregori, Josep; Esteban, Juan Ignacio; Ribera, Esteban; Quer, Josep; Puig, Lluís; Sauleda, Sílvia

    2017-09-01

    Human immunodeficiency virus 1 (HIV-1) subtype B is predominant in Spain. However, the recent arrival of immigrant populations has increased the prevalence of non-B subtypes and circulating recombinant forms. The objective of this study was to determine the prevalence of HIV-1 subtypes and transmitted drug-resistance mutations in blood donors from the Catalonian region (northeastern Spain). HIV-1-positive blood donors identified in Catalonia from 2005 to 2014 were included. Demographic variables and risk factors for HIV-1 acquisition were recorded. HIV-1 subtyping was carried out by HIV-1 DNA polymerase region sequencing, and phylogenetic analyses were performed using the neighbor-joining method. During the study period, 2.8 million blood donations were screened, and 214 HIV-1-positive donors were identified, yielding an overall prevalence of 7.7 per 100,000 donations (89% men; mean age, 34 ± 10 years). Most HIV-1-positive donors were native to Spain (81%), and 61% were regular blood donors. When risk factors were known, 62% reportedly were men who had sex with men. HIV-1 subtyping was possible in 176 HIV-1-positive individuals: 143 (81%) had HIV-1 subtype B, and 33 (19%) had non-B subtypes. Most HIV-1 non-B subtypes were circulating recombinant forms (n = 20; 61%). Factors associated with HIV-1 subtype B were male sex (p = 0.007) and men who had sex with men (p HIV-1-positive blood donors in Catalonia. Continuous local epidemiological surveillance is required to implement optimal prevention strategies for controlling transfusion-transmitted HIV and to improve health policies regarding HIV infection. © 2017 AABB.

  18. An improved chaotic fruit fly optimization based on a mutation strategy for simultaneous feature selection and parameter optimization for SVM and its applications

    Science.gov (United States)

    Lou, Xin Yuan; Sun, Lin Fu

    2017-01-01

    This paper proposes a new support vector machine (SVM) optimization scheme based on an improved chaotic fly optimization algorithm (FOA) with a mutation strategy to simultaneously perform parameter setting turning for the SVM and feature selection. In the improved FOA, the chaotic particle initializes the fruit fly swarm location and replaces the expression of distance for the fruit fly to find the food source. However, the proposed mutation strategy uses two distinct generative mechanisms for new food sources at the osphresis phase, allowing the algorithm procedure to search for the optimal solution in both the whole solution space and within the local solution space containing the fruit fly swarm location. In an evaluation based on a group of ten benchmark problems, the proposed algorithm’s performance is compared with that of other well-known algorithms, and the results support the superiority of the proposed algorithm. Moreover, this algorithm is successfully applied in a SVM to perform both parameter setting turning for the SVM and feature selection to solve real-world classification problems. This method is called chaotic fruit fly optimization algorithm (CIFOA)-SVM and has been shown to be a more robust and effective optimization method than other well-known methods, particularly in terms of solving the medical diagnosis problem and the credit card problem. PMID:28369096

  19. A Generalized Measure for the Optimal Portfolio Selection Problem and its Explicit Solution

    Directory of Open Access Journals (Sweden)

    Zinoviy Landsman

    2018-03-01

    Full Text Available In this paper, we offer a novel class of utility functions applied to optimal portfolio selection. This class incorporates as special cases important measures such as the mean-variance, Sharpe ratio, mean-standard deviation and others. We provide an explicit solution to the problem of optimal portfolio selection based on this class. Furthermore, we show that each measure in this class generally reduces to the efficient frontier that coincides or belongs to the classical mean-variance efficient frontier. In addition, a condition is provided for the existence of the a one-to-one correspondence between the parameter of this class of utility functions and the trade-off parameter λ in the mean-variance utility function. This correspondence essentially provides insight into the choice of this parameter. We illustrate our results by taking a portfolio of stocks from National Association of Securities Dealers Automated Quotation (NASDAQ.

  20. A feasibility study: Selection of a personalized radiotherapy fractionation schedule using spatiotemporal optimization

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Minsun, E-mail: mk688@uw.edu; Stewart, Robert D. [Department of Radiation Oncology, University of Washington, Seattle, Washington 98195-6043 (United States); Phillips, Mark H. [Departments of Radiation Oncology and Neurological Surgery, University of Washington, Seattle, Washington 98195-6043 (United States)

    2015-11-15

    Purpose: To investigate the impact of using spatiotemporal optimization, i.e., intensity-modulated spatial optimization followed by fractionation schedule optimization, to select the patient-specific fractionation schedule that maximizes the tumor biologically equivalent dose (BED) under dose constraints for multiple organs-at-risk (OARs). Methods: Spatiotemporal optimization was applied to a variety of lung tumors in a phantom geometry using a range of tumor sizes and locations. The optimal fractionation schedule for a patient using the linear-quadratic cell survival model depends on the tumor and OAR sensitivity to fraction size (α/β), the effective tumor doubling time (T{sub d}), and the size and location of tumor target relative to one or more OARs (dose distribution). The authors used a spatiotemporal optimization method to identify the optimal number of fractions N that maximizes the 3D tumor BED distribution for 16 lung phantom cases. The selection of the optimal fractionation schedule used equivalent (30-fraction) OAR constraints for the heart (D{sub mean} ≤ 45 Gy), lungs (D{sub mean} ≤ 20 Gy), cord (D{sub max} ≤ 45 Gy), esophagus (D{sub max} ≤ 63 Gy), and unspecified tissues (D{sub 05} ≤ 60 Gy). To assess plan quality, the authors compared the minimum, mean, maximum, and D{sub 95} of tumor BED, as well as the equivalent uniform dose (EUD) for optimized plans to conventional intensity-modulated radiation therapy plans prescribing 60 Gy in 30 fractions. A sensitivity analysis was performed to assess the effects of T{sub d} (3–100 days), tumor lag-time (T{sub k} = 0–10 days), and the size of tumors on optimal fractionation schedule. Results: Using an α/β ratio of 10 Gy, the average values of tumor max, min, mean BED, and D{sub 95} were up to 19%, 21%, 20%, and 19% larger than those from conventional prescription, depending on T{sub d} and T{sub k} used. Tumor EUD was up to 17% larger than the conventional prescription. For fast proliferating

  1. Achieving Optimal Self-Adaptivity for Dynamic Tuning of Organic Semiconductors through Resonance Engineering.

    Science.gov (United States)

    Tao, Ye; Xu, Lijia; Zhang, Zhen; Chen, Runfeng; Li, Huanhuan; Xu, Hui; Zheng, Chao; Huang, Wei

    2016-08-03

    Current static-state explorations of organic semiconductors for optimal material properties and device performance are hindered by limited insights into the dynamically changed molecular states and charge transport and energy transfer processes upon device operation. Here, we propose a simple yet successful strategy, resonance variation-based dynamic adaptation (RVDA), to realize optimized self-adaptive properties in donor-resonance-acceptor molecules by engineering the resonance variation for dynamic tuning of organic semiconductors. Organic light-emitting diodes hosted by these RVDA materials exhibit remarkably high performance, with external quantum efficiencies up to 21.7% and favorable device stability. Our approach, which supports simultaneous realization of dynamically adapted and selectively enhanced properties via resonance engineering, illustrates a feasible design map for the preparation of smart organic semiconductors capable of dynamic structure and property modulations, promoting the studies of organic electronics from static to dynamic.

  2. A screening method for the optimal selection of plate heat exchanger configurations

    Directory of Open Access Journals (Sweden)

    Pinto J.M.

    2002-01-01

    Full Text Available An optimization method for determining the best configuration(s of gasketed plate heat exchangers is presented. The objective is to select the configuration(s with the minimum heat transfer area that still satisfies constraints on the number of channels, the pressure drop of both fluids, the channel flow velocities and the exchanger thermal effectiveness. The configuration of the exchanger is defined by six parameters, which are as follows: the number of channels, the numbers of passes on each side, the fluid locations, the feed positions and the type of flow in the channels. The resulting configuration optimization problem is formulated as the minimization of the exchanger heat transfer area and a screening procedure is proposed for its solution. In this procedure, subsets of constraints are successively applied to eliminate infeasible and nonoptimal solutions. Examples show that the optimization method is able to successfully determine a set of optimal configurations with a minimum number of exchanger evaluations. Approximately 5 % of the pressure drop and channel velocity calculations and 1 % of the thermal simulations are required for the solution.

  3. Secrets and disclosure in donor conception.

    Science.gov (United States)

    Frith, Lucy; Blyth, Eric; Crawshaw, Marilyn; van den Akker, Olga

    2018-01-01

    This article considers the disclosure, sharing and exchange of information on being donor conceived within families, drawing on data from a study undertaken with donor-conceived adults registered with UK Donor Link (a voluntary DNA-linking register). This paper considers the narratives of how respondents found out they were donor-conceived and what events triggered disclosure of this information. This paper then goes on to examine the role secrecy played in their family life and uses the concept of 'display' to explore how secrecy affected their relationships with their immediate and extended family. Secrets are notoriously 'leaky' and we found complex patterns of knowing and uncertainty about whom in the family knew that the person was donor-conceived. We argue that what is kept secret and from whom provides insights into the multifaceted web of social relationships that can be created by donor-conception, and how knowledge can be managed and controlled in attempts to display and maintain family narratives of biogenetic connection. © 2017 Foundation for the Sociology of Health & Illness.

  4. Using Random Forests to Select Optimal Input Variables for Short-Term Wind Speed Forecasting Models

    Directory of Open Access Journals (Sweden)

    Hui Wang

    2017-10-01

    Full Text Available Achieving relatively high-accuracy short-term wind speed forecasting estimates is a precondition for the construction and grid-connected operation of wind power forecasting systems for wind farms. Currently, most research is focused on the structure of forecasting models and does not consider the selection of input variables, which can have significant impacts on forecasting performance. This paper presents an input variable selection method for wind speed forecasting models. The candidate input variables for various leading periods are selected and random forests (RF is employed to evaluate the importance of all variable as features. The feature subset with the best evaluation performance is selected as the optimal feature set. Then, kernel-based extreme learning machine is constructed to evaluate the performance of input variables selection based on RF. The results of the case study show that by removing the uncorrelated and redundant features, RF effectively extracts the most strongly correlated set of features from the candidate input variables. By finding the optimal feature combination to represent the original information, RF simplifies the structure of the wind speed forecasting model, shortens the training time required, and substantially improves the model’s accuracy and generalization ability, demonstrating that the input variables selected by RF are effective.

  5. Optimality and stability of symmetric evolutionary games with applications in genetic selection.

    Science.gov (United States)

    Huang, Yuanyuan; Hao, Yiping; Wang, Min; Zhou, Wen; Wu, Zhijun

    2015-06-01

    Symmetric evolutionary games, i.e., evolutionary games with symmetric fitness matrices, have important applications in population genetics, where they can be used to model for example the selection and evolution of the genotypes of a given population. In this paper, we review the theory for obtaining optimal and stable strategies for symmetric evolutionary games, and provide some new proofs and computational methods. In particular, we review the relationship between the symmetric evolutionary game and the generalized knapsack problem, and discuss the first and second order necessary and sufficient conditions that can be derived from this relationship for testing the optimality and stability of the strategies. Some of the conditions are given in different forms from those in previous work and can be verified more efficiently. We also derive more efficient computational methods for the evaluation of the conditions than conventional approaches. We demonstrate how these conditions can be applied to justifying the strategies and their stabilities for a special class of genetic selection games including some in the study of genetic disorders.

  6. Efficient Iris Recognition Based on Optimal Subfeature Selection and Weighted Subregion Fusion

    Science.gov (United States)

    Deng, Ning

    2014-01-01

    In this paper, we propose three discriminative feature selection strategies and weighted subregion matching method to improve the performance of iris recognition system. Firstly, we introduce the process of feature extraction and representation based on scale invariant feature transformation (SIFT) in detail. Secondly, three strategies are described, which are orientation probability distribution function (OPDF) based strategy to delete some redundant feature keypoints, magnitude probability distribution function (MPDF) based strategy to reduce dimensionality of feature element, and compounded strategy combined OPDF and MPDF to further select optimal subfeature. Thirdly, to make matching more effective, this paper proposes a novel matching method based on weighted sub-region matching fusion. Particle swarm optimization is utilized to accelerate achieve different sub-region's weights and then weighted different subregions' matching scores to generate the final decision. The experimental results, on three public and renowned iris databases (CASIA-V3 Interval, Lamp, andMMU-V1), demonstrate that our proposed methods outperform some of the existing methods in terms of correct recognition rate, equal error rate, and computation complexity. PMID:24683317

  7. Efficient Iris Recognition Based on Optimal Subfeature Selection and Weighted Subregion Fusion

    Directory of Open Access Journals (Sweden)

    Ying Chen

    2014-01-01

    Full Text Available In this paper, we propose three discriminative feature selection strategies and weighted subregion matching method to improve the performance of iris recognition system. Firstly, we introduce the process of feature extraction and representation based on scale invariant feature transformation (SIFT in detail. Secondly, three strategies are described, which are orientation probability distribution function (OPDF based strategy to delete some redundant feature keypoints, magnitude probability distribution function (MPDF based strategy to reduce dimensionality of feature element, and compounded strategy combined OPDF and MPDF to further select optimal subfeature. Thirdly, to make matching more effective, this paper proposes a novel matching method based on weighted sub-region matching fusion. Particle swarm optimization is utilized to accelerate achieve different sub-region’s weights and then weighted different subregions’ matching scores to generate the final decision. The experimental results, on three public and renowned iris databases (CASIA-V3 Interval, Lamp, andMMU-V1, demonstrate that our proposed methods outperform some of the existing methods in terms of correct recognition rate, equal error rate, and computation complexity.

  8. Efficient iris recognition based on optimal subfeature selection and weighted subregion fusion.

    Science.gov (United States)

    Chen, Ying; Liu, Yuanning; Zhu, Xiaodong; He, Fei; Wang, Hongye; Deng, Ning

    2014-01-01

    In this paper, we propose three discriminative feature selection strategies and weighted subregion matching method to improve the performance of iris recognition system. Firstly, we introduce the process of feature extraction and representation based on scale invariant feature transformation (SIFT) in detail. Secondly, three strategies are described, which are orientation probability distribution function (OPDF) based strategy to delete some redundant feature keypoints, magnitude probability distribution function (MPDF) based strategy to reduce dimensionality of feature element, and compounded strategy combined OPDF and MPDF to further select optimal subfeature. Thirdly, to make matching more effective, this paper proposes a novel matching method based on weighted sub-region matching fusion. Particle swarm optimization is utilized to accelerate achieve different sub-region's weights and then weighted different subregions' matching scores to generate the final decision. The experimental results, on three public and renowned iris databases (CASIA-V3 Interval, Lamp, and MMU-V1), demonstrate that our proposed methods outperform some of the existing methods in terms of correct recognition rate, equal error rate, and computation complexity.

  9. Absence of beta-amyloid in cortical cataracts of donors with and without Alzheimer's disease.

    Science.gov (United States)

    Michael, Ralph; Rosandić, Jurja; Montenegro, Gustavo A; Lobato, Elvira; Tresserra, Francisco; Barraquer, Rafael I; Vrensen, Gijs F J M

    2013-01-01

    Eye lenses from human donors with and without Alzheimer's disease (AD) were studied to evaluate the presence of amyloid in cortical cataract. We obtained 39 lenses from 21 postmortem donors with AD and 15 lenses from age-matched controls provided by the Banco de Ojos para Tratamientos de la Ceguera (Barcelona, Spain). For 17 donors, AD was clinically diagnosed by general physicians and for 4 donors the AD diagnosis was neuropathologically confirmed. Of the 21 donors with AD, 6 had pronounced bilateral cortical lens opacities and 15 only minor or no cortical opacities. As controls, 7 donors with pronounced cortical opacities and 8 donors with almost transparent lenses were selected. All lenses were photographed in a dark field stereomicroscope. Histological sections were analyzed using a standard and a more sensitive Congo red protocol, thioflavin staining and beta-amyloid immunohistochemistry. Brain tissue from two donors, one with cerebral amyloid angiopathy and another with advanced AD-related changes and one cornea with lattice dystrophy were used as positive controls for the staining techniques. Thioflavin, standard and modified Congo red staining were positive in the control brain tissues and in the dystrophic cornea. Beta-amyloid immunohistochemistry was positive in the brain tissues but not in the cornea sample. Lenses from control and AD donors were, without exception, negative after Congo red, thioflavin, and beta-amyloid immunohistochemical staining. The results of the positive control tissues correspond well with known observations in AD, amyloid angiopathy and corneas with lattice dystrophy. The absence of staining in AD and control lenses with the techniques employed lead us to conclude that there is no beta-amyloid in lenses from donors with AD or in control cortical cataracts. The inconsistency with previous studies of Goldstein et al. (2003) and Moncaster et al. (2010), both of which demonstrated positive Congo red, thioflavin, and beta

  10. Organ donors: deceased or alive? Quo vadis?

    Science.gov (United States)

    Rozental, R

    2006-01-01

    Irrespectively of universal shortage of donor organs there is a tendency of increasing the number of transplantations from living and deceased donors. Each of these two methods has positive and negative features. The main obstacles using living donors are health hazard, necessity to solve certain donor's social and psychological problems, possibility of organ trade and moving. The main problems connected with organ retrieval from deceased donors are possible conflicts with public opinion: difficulties in interpretation of brain death, legislation, obtaining of informed consent from donor's relatives, etc. Future progress in organ transplantation may take place through activation of organ retrieval from deceased donors. The most perspective ways are change to presumed consent in all countries, establishing of centralized system of donor detection and registration, intensification of transplant coordination, active contacts with mass-media, etc. It is necessary to increase (enhance) participation of the members of the public in organ donation process, to develop solidarity among the public members and to involve public authorities to deal with this problem. Bioethical standards should be put in accordance with common progress and some ethical traditions should be changed.

  11. First UK case report of kidney transplantation from an HIV-infected deceased donor to two HIV-infected recipients.

    Science.gov (United States)

    Nolan, Eileen; Karydis, Nikolaos; Drage, Martin; Hilton, Rachel

    2018-04-01

    Kidney transplantation is now considered the treatment of choice for many human immunodeficiency virus (HIV)-infected patients with end-stage renal disease (ESRD). Graft survival rates using HIV-negative donors and carefully selected HIV-positive ESRD patients are similar to those observed in HIV-uninfected kidney transplant recipients. To address the relative shortfall in donated organs it has been proposed that organs from HIV-infected deceased donors might be allocated to HIV-infected patients on the transplant waiting list. Preliminary experience in South Africa reports promising short-term outcomes in a small number of HIV-infected recipients of kidney transplants from HIV-infected donors. We sought to replicate this experience in the UK by accepting kidney offers from HIV infected deceased donors for patients with HIV-infection on the kidney transplant waiting list. Here we report the UK's first cases of kidney transplantation between HIV-positive donors and recipients.

  12. Oocyte cryopreservation for donor egg banking.

    Science.gov (United States)

    Cobo, Ana; Remohí, José; Chang, Ching-Chien; Nagy, Zsolt Peter

    2011-09-01

    Oocyte donation is an efficient alternative to using own oocytes in IVF treatment for different indications. Unfortunately, 'traditional' (fresh) egg donations are challenged with inefficiency, difficulties of synchronization, very long waiting periods and lack of quarantine measures. Given the recent improvements in the efficiency of oocyte cryopreservation, it is reasonable to examine if egg donation through oocyte cryopreservation has merits. The objective of the current manuscript is to review existing literature on this topic and to report on the most recent outcomes from two established donor cryobank centres. Reports on egg donation using slow freezing are scarce and though results are encouraging, outcomes are not yet comparable to a fresh egg donation treatment. Vitrification on the other hand appears to provide high survival rates (90%) of donor oocytes and comparable fertilization, embryo development, implantation and pregnancy rates to traditional (fresh) egg donation. Besides the excellent outcomes, the ease of use for both donors and recipients, higher efficiency, lower cost and avoiding the problem of synchronization are all features associated with the benefit of a donor egg cryobank and makes it likely that this approach becomes the future standard of care. Oocyte donation is one of the last resorts in IVF treatment for couples challenged with infertility problems. However, traditional (fresh) egg donation, as it is performed today, is not very efficient, as typically all eggs from one donor are given to only one recipient, it is arduous as it requires an excellent synchronization between the donor and recipient and there are months or years of waiting time. Because of the development of an efficient oocyte cryopreservation technique, it is now possible to cryo-store donor (as well as non-donor) eggs, maintaining their viability and allowing their use whenever there is demand. Therefore, creating a donor oocyte cryobank would carry many advantages

  13. TreePOD: Sensitivity-Aware Selection of Pareto-Optimal Decision Trees.

    Science.gov (United States)

    Muhlbacher, Thomas; Linhardt, Lorenz; Moller, Torsten; Piringer, Harald

    2018-01-01

    Balancing accuracy gains with other objectives such as interpretability is a key challenge when building decision trees. However, this process is difficult to automate because it involves know-how about the domain as well as the purpose of the model. This paper presents TreePOD, a new approach for sensitivity-aware model selection along trade-offs. TreePOD is based on exploring a large set of candidate trees generated by sampling the parameters of tree construction algorithms. Based on this set, visualizations of quantitative and qualitative tree aspects provide a comprehensive overview of possible tree characteristics. Along trade-offs between two objectives, TreePOD provides efficient selection guidance by focusing on Pareto-optimal tree candidates. TreePOD also conveys the sensitivities of tree characteristics on variations of selected parameters by extending the tree generation process with a full-factorial sampling. We demonstrate how TreePOD supports a variety of tasks involved in decision tree selection and describe its integration in a holistic workflow for building and selecting decision trees. For evaluation, we illustrate a case study for predicting critical power grid states, and we report qualitative feedback from domain experts in the energy sector. This feedback suggests that TreePOD enables users with and without statistical background a confident and efficient identification of suitable decision trees.

  14. Comonotonic approximations for a generalized provisioning problem with application to optimal portfolio selection

    NARCIS (Netherlands)

    van Weert, K.; Dhaene, J.; Goovaerts, M.

    2011-01-01

    In this paper we discuss multiperiod portfolio selection problems related to a specific provisioning problem. Our results are an extension of Dhaene et al. (2005) [14], where optimal constant mix investment strategies are obtained in a provisioning and savings context, using an analytical approach

  15. Donor human milk for preterm infants

    DEFF Research Database (Denmark)

    Arslanoglu, Sertac; Corpeleijn, Willemijn; Moro, Guido

    2013-01-01

    guidelines. Storage and processing of human milk reduces some biological components, which may diminish its health benefits. From a nutritional point of view, DHM, like HM, does not meet the requirements of preterm infants, necessitating a specific fortification regimen to optimize growth. Future research......The Committee on Nutrition of the European Society for Pediatric Gastroenterology, Hepatology, and Nutrition aims to document the existing evidence of the benefits and common concerns deriving from the use of donor human milk (DHM) in preterm infants. The comment also outlines gaps in knowledge...... and gives recommendations for practice and suggestions for future research directions. Protection against necrotizing enterocolitis is the major clinical benefit deriving from the use of DHM when compared with formula. Limited data also suggest unfortified DHM to be associated with improved feeding...

  16. Improved in-tube electro-membrane extraction followed by high-performance liquid chromatography for simple and selective determination of ionic compounds: Optimization by central composite design.

    Science.gov (United States)

    Bazregar, Mohammad; Rajabi, Maryam; Yamini, Yadollah; Asghari, Alireza

    2017-07-01

    In this work, an efficient sample clean-up method, named in-tube electro-membrane extraction, is modified to resolve the formation of bubbles in the extraction process. This modified method is applied for the extraction of two model analytes including tartrazine and sunset yellow from food samples. The method is based on the electro-kinetic migration of ionized compounds by the application of an electrical potential difference, and on this basis the analytes under investigation, as anionic compounds, simply migrate from the donor phase and concentrate in the acceptor phase. A thin polypropylene sheet placed in the tube acts as a support for the membrane solvent, and it separates 30 μL of the aqueous acceptor from 1.2 mL of the aqueous donor. This setup can be used to solve the problem of extracting highly hydrophilic analytes. Response surface methodology is used for optimization of the experimental parameters so that under the optimized conditions, the method provides a good linearity in the range of 50-1000 ng/mL, low limits of detection (15-25 ng/mL), good extraction repeatabilities (relative standard deviations below 8.1%, n = 5), and high extraction recoveries (54-76%). © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Donor transplant programme

    International Nuclear Information System (INIS)

    Abu Bakar Sulaiman

    1999-01-01

    The transplantation of organs and tissues from one human to another human has become an essential and well established form of therapy for many types of organ and tissue failure. In Malaysia, kidney, cornea and bone marrow transplantation are well established. Recently, liver, bone and heart transplanation have been performed. Unfortunately, because of the lack of cadaveric organ donation, only a limited number of solid organ transplantation have been performed. The cadaveric organ donor rate in Malaysia is low at less than one per million population. The first tissue transplanted in Malaysia was the cornea which was performed in the early 1970s. At that time and even now the majority of corneas came from Sri Lanka. The first kidney transplant was performed in 1975 from a live related donor. The majority of the 629 kidney transplants done at Hospital Kuala Lumpur to date have been from live related donors. Only 35 were from cadaver donors. Similarly, the liver transplantation programme which started in 1995 are from live related donors. A more concerted effort has been made recently to increase the awareness of the public and the health professionals on organ and tissue donation. This national effort to promote organ and tissue donation seems to have gathered momentum in 1997 with the first heart transplant successfully performed at the National Heart Institute. The rate of cadaveric donors has also increased from a previous average of I to 2 per year to 6 per year in the last one year. These developments are most encouraging and may signal the coming of age of our transplantati on programme. The Ministry of Health in conjunction with various institutions, organizations and professional groups, have taken a number of proactive measures to facilitate the development of the cadaveric organ donation programme. Efforts to increase public awareness and to overcome the negative cultural attitude towards organ donation have been intensified. Equally important are efforts

  18. Inter-donor variation in cell subset specific immune signaling responses in healthy individuals.

    Science.gov (United States)

    Longo, Diane M; Louie, Brent; Wang, Ena; Pos, Zoltan; Marincola, Francesco M; Hawtin, Rachael E; Cesano, Alessandra

    2012-01-01

    exemplify the application of SCNP to provide a detailed characterization of inter-donor variation in immune signaling pathway activation in a healthy donor cohort. This dataset provides a basis for identifying cell subpopulation specific immune signaling abnormalities in cancer and immune-mediated diseases. Building upon these data in future studies may help inform on disease etiology, maintenance and therapeutic selection.

  19. Socioepidemiological screening of serologically ineligible blood donors due to Chagas disease for the definition of inconclusive cases

    Directory of Open Access Journals (Sweden)

    Márcia M Ferreira-Silva

    2010-09-01

    Full Text Available Epidemiological screening combined with serological tests has become an important tool at blood banks for the characterization of donors with or without Trypanosoma cruzi infection. Thus, the objective of the present study was to describe the sociodemographic and epidemiological characteristics of blood donors with non-negative serology for T. cruzito determine possible risk factors associated with serological ineligibility. Sociodemographic and epidemiological data were collected by analysis of patient histories and interviews. The data were analyzed descriptively using absolute and relative frequencies and odds ratio (OR evaluation. The frequency of serological ineligibility was 0.28%, with a predominance of inconclusive reactions (52% and seropositivity among first-time donors (OR = 607, donors older than 30 years (OR = 3.7, females (OR = 1.9, donors from risk areas (OR = 4 and subjects living in rural areas (OR = 1.7. The risk of seropositivity was higher among donors who had contact with the triatomine vector (OR = 11.7 and those with a family history of Chagas disease (OR = 4.8. The results demonstrate the value of detailed clinical-epidemiological screening as an auxiliary tool for serological definition that, together with more specific and more sensitive laboratory methods, will guarantee a higher efficacy in the selection of donors at blood centres.

  20. Seropositive abdominal and thoracic donor organs are largely underutilized.

    Science.gov (United States)

    Taylor, R M; Pietroski, R E; Hagan, M; Eisenbrey, A B; Fontana, R J

    2010-12-01

    The aim of this study was to describe the epidemiology and utilization of anti-hepatitis B core protein(+) and anti-hepatitis C virus(+) organ donor referrals in a large organ procurement organization. Between 1995 and 2006, 3,134 deceased organ donor referrals were tested for anti-HBc and anti-HCV using commercial assays. The prevalence of anti-HCV(+) organ donor referrals significantly increased from 3.4% in 1994-1996 to 8.1% in 2003-2005 (P organ donor referrals remained unchanged at 3%-4% (P = .20). The 112 anti-HBc(+) (3.5%) and 173 anti-HCV(+) (5.5%) organ donor referrals were significantly older and more likely to be noncaucasian than seronegative organ donor referrals (P donor organs were significantly lower compared with seronegative organ donors (P donors over time (21% vs 46%; P = .026), whereas utilization of anti-HCV(+) liver donors remained unchanged over time (5% vs 18%; P = .303). In summary, the proportion of anti-HCV(+) organ donor referrals has significantly increased and the proportion of anti-HBc(+) organ donor referrals has remained stable. Both thoracic and abdominal organs from seropositive donors are largely underutilized. Copyright © 2010 Elsevier Inc. All rights reserved.

  1. Optimization Techniques for Design Problems in Selected Areas in WSNs: A Tutorial.

    Science.gov (United States)

    Ibrahim, Ahmed; Alfa, Attahiru

    2017-08-01

    This paper is intended to serve as an overview of, and mostly a tutorial to illustrate, the optimization techniques used in several different key design aspects that have been considered in the literature of wireless sensor networks (WSNs). It targets the researchers who are new to the mathematical optimization tool, and wish to apply it to WSN design problems. We hence divide the paper into two main parts. One part is dedicated to introduce optimization theory and an overview on some of its techniques that could be helpful in design problem in WSNs. In the second part, we present a number of design aspects that we came across in the WSN literature in which mathematical optimization methods have been used in the design. For each design aspect, a key paper is selected, and for each we explain the formulation techniques and the solution methods implemented. We also provide in-depth analyses and assessments of the problem formulations, the corresponding solution techniques and experimental procedures in some of these papers. The analyses and assessments, which are provided in the form of comments, are meant to reflect the points that we believe should be taken into account when using optimization as a tool for design purposes.

  2. Selective pressures on C4 photosynthesis evolution in grasses through the lens of optimality

    OpenAIRE

    Akcay, Erol; Zhou, Haoran; Helliker, Brent

    2016-01-01

    CO2, temperature, water availability and light intensity were potential selective pressures to propel the initial evolution and global expansion of C4 photosynthesis in grasses. To tease apart the primary selective pressures along the evolutionary trajectory, we coupled photosynthesis and hydraulics models and optimized photosynthesis over stomatal resistance and leaf/fine-root allocation. We also examined the importance of nitrogen reallocation from the dark to the light reactions. Our resul...

  3. Factors influencing the virological testing of cornea donors.

    Science.gov (United States)

    Röck, Tobias; Beck, Robert; Jürgens, Stefan; Bartz-Schmidt, Karl Ulrich; Bramkamp, Matthias; Thaler, Sebastian; Röck, Daniel

    2017-11-01

    To assess the influence of donor, environment, and logistical factors on the results of virological testing of blood samples from cornea donors.Data from 670 consecutive cornea donors were analyzed retrospectively. Logistic regression analysis was used to assess the influence of different factors on the results of virological testing of blood samples from cornea donors.The mean annual rate of donors with serology-reactive or not evaluable result was 14.8% (99 of 670) (range 11.9%-16.9%). The cause of donor death by cancer increased the risk of serology-reactive or not evaluable result (P = .0300). Prolonged time between death and post mortem blood removal was associated with a higher rate of serology-reactive or not evaluable result (P donors, sex, and donor age had no significant impact on the results of virological testing of blood samples from cornea donors.The cause of donor death by cancer and a prolonged time between death and post mortem blood removal seem to be mainly responsible for serology-reactive or not evaluable result of blood samples from cornea donors. The percentage of discarded corneas caused by serology-reactive or not evaluable result may be reduced by shortening the period of time between death and post mortem blood removal. Copyright © 2017 The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved.

  4. New hydrogen donors in germanium

    International Nuclear Information System (INIS)

    Pokotilo, Yu.M.; Petukh, A.N.; Litvinov, V.V.

    2003-01-01

    The electrophysical properties of the n-type conductivity germanium, irradiated through protons, is studied by the volt-farad method. It is shown that the heat treatment of the implanted germanium at the temperature of 200-300 deg C leads to formation of the fast-diffusing second-rate donors. It is established that the diffusion coefficient of the identified donors coincides with the diffusion coefficient of the atomic hydrogen with an account of the capture on the traps. The conclusion is made, that the atomic hydrogen is the second-rate donor center in germanium [ru

  5. Optimal Training for Time-Selective Wireless Fading Channels Using Cutoff Rate

    Directory of Open Access Journals (Sweden)

    Tong Lang

    2006-01-01

    Full Text Available We consider the optimal allocation of resources—power and bandwidth—between training and data transmissions for single-user time-selective Rayleigh flat-fading channels under the cutoff rate criterion. The transmitter exploits statistical channel state information (CSI in the form of the channel Doppler spectrum to embed pilot symbols into the transmission stream. At the receiver, instantaneous, though imperfect, CSI is acquired through minimum mean-square estimation of the channel based on some set of pilot observations. We compute the ergodic cutoff rate for this scenario. Assuming estimator-based interleaving and -PSK inputs, we study two special cases in-depth. First, we derive the optimal resource allocation for the Gauss-Markov correlation model. Next, we validate and refine these insights by studying resource allocation for the Jakes model.

  6. Energy-efficient relay selection and optimal power allocation for performance-constrained dual-hop variable-gain AF relaying

    KAUST Repository

    Zafar, Ammar

    2013-12-01

    This paper investigates the energy-efficiency enhancement of a variable-gain dual-hop amplify-and-forward (AF) relay network utilizing selective relaying. The objective is to minimize the total consumed power while keeping the end-to-end signal-to-noise-ratio (SNR) above a certain peak value and satisfying the peak power constraints at the source and relay nodes. To achieve this objective, an optimal relay selection and power allocation strategy is derived by solving the power minimization problem. Numerical results show that the derived optimal strategy enhances the energy-efficiency as compared to a benchmark scheme in which both the source and the selected relay transmit at peak power. © 2013 IEEE.

  7. Optimal Selection Method of Process Patents for Technology Transfer Using Fuzzy Linguistic Computing

    Directory of Open Access Journals (Sweden)

    Gangfeng Wang

    2014-01-01

    Full Text Available Under the open innovation paradigm, technology transfer of process patents is one of the most important mechanisms for manufacturing companies to implement process innovation and enhance the competitive edge. To achieve promising technology transfers, we need to evaluate the feasibility of process patents and optimally select the most appropriate patent according to the actual manufacturing situation. Hence, this paper proposes an optimal selection method of process patents using multiple criteria decision-making and 2-tuple fuzzy linguistic computing to avoid information loss during the processes of evaluation integration. An evaluation index system for technology transfer feasibility of process patents is designed initially. Then, fuzzy linguistic computing approach is applied to aggregate the evaluations of criteria weights for each criterion and corresponding subcriteria. Furthermore, performance ratings for subcriteria and fuzzy aggregated ratings of criteria are calculated. Thus, we obtain the overall technology transfer feasibility of patent alternatives. Finally, a case study of aeroengine turbine manufacturing is presented to demonstrate the applicability of the proposed method.

  8. Negotiating boundaries: Accessing donor gametes in India.

    Science.gov (United States)

    Widge, A; Cleland, J

    2011-01-01

    This paper documents how couples and providers access donor materials for conception in the Indian context and perceptions about using them. The objective is to facilitate understanding of critical issues and relevant concerns. A postal survey was conducted with a sample of 6000 gynaecologists and in-depth interviews were -conducted with 39 gynaecologists in four cities. Donor gametes are relatively more acceptable than a few years ago, especially if confidentiality can be -maintained, though lack of availability of donor materials is sometimes an impediment to infertility treatment. Donor sperms are usually accessed from in-house or commercial sperm banks, pathology laboratories, IVF centres, -professional donors, relatives or friends. There is scepticism about screening procedures of sperm banks. Donor eggs are usually accessed from voluntary donors, friends, relatives, egg sharing programmes, donation from other patients, advertising and commercial donors. There are several concerns regarding informed consent for using donated gametes, using -relatives and friends gametes, the unregulated use of gametes and embryos, record keeping and documentation, -unethical and corrupt practices and commercialisation. These issues need to be addressed by patients, providers and regulatory authorities by providing -information, counselling, ensuring informed consent, addressing exploitation and commercialisation, ensuring -monitoring, proper documentation and transparency.

  9. Outcomes of hematopoietic cell transplantation using donors or recipients with inherited chromosomally integrated HHV-6.

    Science.gov (United States)

    Hill, Joshua A; Magaret, Amalia S; Hall-Sedlak, Ruth; Mikhaylova, Anna; Huang, Meei-Li; Sandmaier, Brenda M; Hansen, John A; Jerome, Keith R; Zerr, Danielle M; Boeckh, Michael

    2017-08-24

    Human herpesvirus 6 (HHV-6) species have a unique ability to integrate into chromosomal telomeres. Mendelian inheritance via gametocyte integration results in HHV-6 in every nucleated cell. The epidemiology and clinical effect of inherited chromosomally integrated HHV-6 (iciHHV-6) in hematopoietic cell transplant (HCT) recipients is unclear. We identified 4319 HCT donor-recipient pairs (8638 subjects) who received an allogeneic HCT and had archived pre-HCT peripheral blood mononuclear cell samples. We screened these samples for iciHHV-6 and compared characteristics of HCT recipients and donors with iciHHV-6 with those of recipients and donors without iciHHV-6, respectively. We calculated Kaplan-Meier probability estimates and Cox proportional hazards models for post-HCT outcomes based on recipient and donor iciHHV-6 status. We identified 60 HCT recipients (1.4%) and 40 donors (0.9%) with iciHHV-6; both recipient and donor harbored iciHHV-6 in 13 HCTs. Thus, there were 87 HCTs (2%) in which the recipient, donor, or both harbored iciHHV-6. Acute graft-versus-host disease (GVHD) grades 2-4 was more frequent when recipients or donors had iciHHV-6 (adjusted hazard ratios, 1.7-1.9; P = .004-.001). Cytomegalovirus viremia (any and high-level) was more frequent among recipients with iciHHV-6 (adjusted HRs, 1.7-3.1; P = .001-.040). Inherited ciHHV-6 status did not significantly affect risk for chronic GVHD, hematopoietic cell engraftment, overall mortality, or nonrelapse mortality. Screening for iciHHV-6 could guide donor selection and post-HCT risk stratification and treatment. Further study is needed to replicate these findings and identify potential mechanisms. © 2017 by The American Society of Hematology.

  10. The effect of variation in donor platelet function on transfusion outcome: a semirandomized controlled trial.

    Science.gov (United States)

    Kelly, Anne M; Garner, Stephen F; Foukaneli, Theodora; Godec, Thomas R; Herbert, Nina; Kahan, Brennan C; Deary, Alison; Bakrania, Lekha; Llewelyn, Charlotte; Ouwehand, Willem H; Williamson, Lorna M; Cardigan, Rebecca A

    2017-07-13

    The effect of variation in platelet function in platelet donors on patient outcome following platelet transfusion is unknown. This trial assessed the hypothesis that platelets collected from donors with highly responsive platelets to agonists in vitro assessed by flow cytometry (high-responder donors) are cleared more quickly from the circulation than those from low-responder donors, resulting in lower platelet count increments following transfusion. This parallel group, semirandomized double-blinded trial was conducted in a single center in the United Kingdom. Eligible patients were those 16 or older with thrombocytopenia secondary to bone marrow failure, requiring prophylactic platelet transfusion. Patients were randomly assigned to receive a platelet donation from a high- or low-responder donor when both were available, or when only 1 type of platelet was available, patients received that. Participants, investigators, and those assessing outcomes were masked to group assignment. The primary end point was the platelet count increment 10 to 90 minutes following transfusion. Analysis was by intention to treat. Fifty-one patients were assigned to receive platelets from low-responder donors, and 49 from high-responder donors (47 of which were randomized and 53 nonrandomized). There was no significant difference in platelet count increment 10 to 90 minutes following transfusion in patients receiving platelets from high-responder (mean, 21.0 × 10 9 /L; 95% confidence interval [CI], 4.9-37.2) or low-responder (mean, 23.3 × 10 9 /L; 95% CI, 7.8-38.9) donors (mean difference, 2.3; 95% CI, -1.1 to 5.7; P = .18). These results support the current policy of not selecting platelet donors on the basis of platelet function for prophylactic platelet transfusion. © 2017 by The American Society of Hematology.

  11. Parvovirus B19 viraemia in Dutch blood donors

    NARCIS (Netherlands)

    Zaaijer, H. L.; Koppelman, M. H. G. M.; Farrington, C. P.

    2004-01-01

    Blood, donated by asymptomatic donors, may contain and transmit parvovirus B19. To investigate the dynamics of parvovirus viraemia in asymptomatic blood donors, we studied the amounts of parvovirus DNA in pools of donor plasma, the prevalence of parvovirus antibodies among blood donors in relation

  12. Intramolecular Charge-Transfer Interaction of Donor-Acceptor-Donor Arrays Based on Anthracene Bisimide.

    Science.gov (United States)

    Iwanaga, Tetsuo; Ogawa, Marina; Yamauchi, Tomokazu; Toyota, Shinji

    2016-05-20

    We designed anthracene bisimide (ABI) derivatives having two triphenylamine (TPA) groups as donor units at the 9,10-positions to form a novel π-conjugated donor-acceptor system. These compounds and their analogues with ethynylene linkers were synthesized by Suzuki-Miyaura and Sonogashira coupling reactions, respectively. In UV-vis spectra, the linker-free derivatives showed broad absorption bands arising from intramolecular charge-transfer interactions. Introducing ethynylene linkers resulted in a considerable red shift of the absorption bands. In fluorescence spectra, the ethynylene derivatives showed intense emission bands at 600-650 nm. Their photophysical and electrochemical properties were compared with those of the corresponding mono TPA derivatives on the basis of theoretical calculations and cyclic voltammetry to evaluate the intramolecular electronic interactions between the donor and acceptor units.

  13. Emergency department referral for organ donation: more organ donors and more organs per donor.

    Science.gov (United States)

    Miller, Lisabeth D; Gardiner, Stuart K; Gubler, K Dean

    2014-05-01

    This study sought to determine whether early referral from the emergency department (ED) would increase the number of organ donors and the number of organs transplanted per donor (OTPD). This is a retrospective cohort analysis of all patients referred to a single organ procurement organization for a period of 60 months. Patients referred for organ donation evaluation from the ED were more likely to become organ donors than patients referred from the intensive care unit (19.3% vs 5.2%, P organ donation from the ED is associated with an increased likelihood of organ recovery and with an increased number of OTPD. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. On the non-stationarity of financial time series: impact on optimal portfolio selection

    International Nuclear Information System (INIS)

    Livan, Giacomo; Inoue, Jun-ichi; Scalas, Enrico

    2012-01-01

    We investigate the possible drawbacks of employing the standard Pearson estimator to measure correlation coefficients between financial stocks in the presence of non-stationary behavior, and we provide empirical evidence against the well-established common knowledge that using longer price time series provides better, more accurate, correlation estimates. Then, we investigate the possible consequences of instabilities in empirical correlation coefficient measurements on optimal portfolio selection. We rely on previously published works which provide a framework allowing us to take into account possible risk underestimations due to the non-optimality of the portfolio weights being used in order to distinguish such non-optimality effects from risk underestimations genuinely due to non-stationarities. We interpret such results in terms of instabilities in some spectral properties of portfolio correlation matrices. (paper)

  15. Optimizing selective cutting strategies for maximum carbon stocks and yield of Moso bamboo forest using BIOME-BGC model.

    Science.gov (United States)

    Mao, Fangjie; Zhou, Guomo; Li, Pingheng; Du, Huaqiang; Xu, Xiaojun; Shi, Yongjun; Mo, Lufeng; Zhou, Yufeng; Tu, Guoqing

    2017-04-15

    The selective cutting method currently used in Moso bamboo forests has resulted in a reduction of stand productivity and carbon sequestration capacity. Given the time and labor expense involved in addressing this problem manually, simulation using an ecosystem model is the most suitable approach. The BIOME-BGC model was improved to suit managed Moso bamboo forests, which was adapted to include age structure, specific ecological processes and management measures of Moso bamboo forest. A field selective cutting experiment was done in nine plots with three cutting intensities (high-intensity, moderate-intensity and low-intensity) during 2010-2013, and biomass of these plots was measured for model validation. Then four selective cutting scenarios were simulated by the improved BIOME-BGC model to optimize the selective cutting timings, intervals, retained ages and intensities. The improved model matched the observed aboveground carbon density and yield of different plots, with a range of relative error from 9.83% to 15.74%. The results of different selective cutting scenarios suggested that the optimal selective cutting measure should be cutting 30% culms of age 6, 80% culms of age 7, and all culms thereafter (above age 8) in winter every other year. The vegetation carbon density and harvested carbon density of this selective cutting method can increase by 74.63% and 21.5%, respectively, compared with the current selective cutting measure. The optimized selective cutting measure developed in this study can significantly promote carbon density, yield, and carbon sink capacity in Moso bamboo forests. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. BLOODR: blood donor and requester mobile application.

    Science.gov (United States)

    Tatikonda, Vamsi Krishna; El-Ocla, Hosam

    2017-01-01

    With rapid increase in the usage of social networks sites across the world, there is also a steady increase in blood donation requests as being noticed in the number of posts on these sites such as Facebook and twitter seeking blood donors. Finding blood donor is a challenging issue in almost every country. There are some blood donor finder applications in the market such as Blood app by Red Cross and Blood Donor Finder application by Neologix. However, more reliable applications that meet the needs of users are prompted. Several software technologies including languages and framework are used to develop our blood-donor web application known as BLOODR application. These technologies comprise Ruby programming language (simply known as Ruby) along with JavaScript and PostgreSQL for database are used. Ruby on Rails (simply known as Rails) is an open source Web framework that makes it possible to quickly and easily create data-based web applications. We show screenshots for the BLOODR application for different types of users including requester, donor, and administrator. Various features of the application are described and their needs of use are analyzed. If a patient needs a blood at a clinic, blood donors in vicinity can be contacted through using a clinic management service provided in this application. Registered donors will get notification for the blood requests only if their blood group is compatible with the requested blood type and in the same city/region. Then matching blood donors can go to the requesting clinic and donate. BLOODR application provides a reliable platform to connect local blood donors with patients. BLOODR creates a communication channel through authenticated clinics whenever a patient needs blood donation. It is a useful tool to find compatible blood donors who can receive blood request posts in their local area. Clinics can use this web application to maintain the blood donation activity. Future improvement of the BLOODR is explained.

  17. Optimal load suitability based RAT selection for HSDPA and IEEE 802.11e

    DEFF Research Database (Denmark)

    Prasad, Ramjee; Cabral, O.; Felez, F.J.

    2009-01-01

    are a premium. This paper investigates cooperation between networks based Radio Access Technology (RAT) selection algorithm that uses suitability to optimize the choice between WiFi and High Speed Downlink Packet Access (HSDPA). It has been shown that this approach has the potential to provide gain...... by allocating a user terminal to the most preferred network based on traffic type and network load. Optimal load threshold values that maximise the total QoS throughput for the given interworking scenario are 0.6 and 0.53 for HSDPA and WiFi, respectively. This corresponds to a CRRM gain on throughput of 80...

  18. Initial experience with purely laparoscopic living-donor right hepatectomy.

    Science.gov (United States)

    Hong, S K; Lee, K W; Choi, Y; Kim, H S; Ahn, S W; Yoon, K C; Kim, H; Yi, N J; Suh, K S

    2018-05-01

    There may be concerns about purely laparoscopic donor right hepatectomy (PLDRH) compared with open donor right hepatectomy, especially when performed by surgeons accustomed to open surgery. This study aimed to describe technical tips and pitfalls in PLDRH. Data from donors who underwent PLDRH at Seoul National University Hospital between December 2015 and July 2017 were analysed retrospectively. Endpoints analysed included intraoperative events and postoperative complications. All operations were performed by a single surgeon with considerable experience in open living donor hepatectomy. A total of 26 donors underwent purely laparoscopic right hepatectomy in the study interval. No donor required transfusion during surgery, whereas two underwent reoperation. In two donors, the dissection plane at the right upper deep portion of the midplane was not correct. One donor experienced portal vein injury during caudate lobe transection, and one developed remnant left hepatic duct stenosis. One donor experienced remnant portal vein angulation owing to a different approach angle, and one experienced arterial damage associated with the use of a laparoscopic energy device. One donor had postoperative bleeding due to masking of potential bleeding foci owing to intra-abdominal pressure during laparoscopy. Two donors experienced right liver surface damage caused by a xiphoid trocar. Purely laparoscopic donor hepatectomy differs from open donor hepatectomy in terms of angle and caudal view. Therefore, surgeons experienced in open donor hepatectomy must gain adequate experience in laparoscopic liver surgery and make adjustments when performing PLDRH. © 2018 BJS Society Ltd Published by John Wiley & Sons Ltd.

  19. P. falciparum malaria prevalence among blood donors in Bamako, Mali.

    Science.gov (United States)

    Kouriba, B; Diarra, A B; Douyon, I; Diabaté, D T; Kamissoko, F; Guitteye, H; Baby, M; Guindo, M A; Doumbo, O K

    2017-06-01

    Malaria parasite is usually transmitted to humans by Anopheles mosquitoes but it can also be transmitted through blood transfusion. Usually malaria transmission is low in African urban settings. In West Africa where the P. falciparum is the most predominant malaria species, there are limited measures to reduce the risk of blood transfusion malaria. The aim of this study was to evaluate the prevalence of P. falciparum malaria carriage among blood donors in the National Blood Center of Bamako, capital city of Mali. The study was conducted using a random sample of 946 blood donors in Bamako, Mali, from January to December 2011. Screening for malaria was performed by thick smear and rapid diagnostic test (RDT). Blood group was typed by Beth-Vincent and Simonin techniques. The frequency of malaria infection was 1.4% by thick smear and 0.8% by the RDT. The pick prevalence of P. falciparum malaria was in rainy season, indicating a probable high seasonal risk of malaria by blood transfusion, in Mali. The prevalence of P. falciparum infection was 2% among donors of group O the majority being in this group. There is a seasonal prevalence of malaria among blood donors in Bamako. A prevention strategy of transfusion malaria based on the combination of selection of blood donors through the medical interview, promoting a voluntary low-risk blood donation and screening all blood bags intended to be transfused to children under 5, pregnant women and immune-compromised patients during transmission season using thick smear will reduce the risk of transfusion malaria in Mali. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  20. Potential organ donor audit in Ireland.

    LENUS (Irish Health Repository)

    Hegarty, M

    2010-11-01

    As increasing demand for organs is a challenge for transplant services worldwide it is essential to audit the process of organ donation. To address this, a national audit of potential organ donors was undertaken across hospitals with Intensive Care Units (N = 36). Questionnaires were returned on all patients (n = 2073) who died in these units from 1\\/9\\/07-31\\/8\\/08; 200 (10%) of these patients were considered for Brain Stem Testing (BST), 158 patients (79%) were diagnosed Brain Stem Dead (BSD) and 138 patients (87%) became potential donors. Consent for donation was given by 92 (69%) next of kin and 90 potential donors (65%) became organ donors. There was no evidence of a large number of potential organ donors being missed. Recommendations included completion of BSTs on all appropriate patients, development of support on BST, referral of all BSD patients to the Organ Procurement Service; enhanced co-ordination within hospitals and sustained information\\/education campaigns.

  1. Optimal Electrode Selection for Electrical Resistance Tomography in Carbon Fiber Reinforced Polymer Composites

    Science.gov (United States)

    Escalona Galvis, Luis Waldo; Diaz-Montiel, Paulina; Venkataraman, Satchi

    2017-01-01

    Electrical Resistance Tomography (ERT) offers a non-destructive evaluation (NDE) technique that takes advantage of the inherent electrical properties in carbon fiber reinforced polymer (CFRP) composites for internal damage characterization. This paper investigates a method of optimum selection of sensing configurations for delamination detection in thick cross-ply laminates using ERT. Reduction in the number of sensing locations and measurements is necessary to minimize hardware and computational effort. The present work explores the use of an effective independence (EI) measure originally proposed for sensor location optimization in experimental vibration modal analysis. The EI measure is used for selecting the minimum set of resistance measurements among all possible combinations resulting from selecting sensing electrode pairs. Singular Value Decomposition (SVD) is applied to obtain a spectral representation of the resistance measurements in the laminate for subsequent EI based reduction to take place. The electrical potential field in a CFRP laminate is calculated using finite element analysis (FEA) applied on models for two different laminate layouts considering a set of specified delamination sizes and locations with two different sensing arrangements. The effectiveness of the EI measure in eliminating redundant electrode pairs is demonstrated by performing inverse identification of damage using the full set and the reduced set of resistance measurements. This investigation shows that the EI measure is effective for optimally selecting the electrode pairs needed for resistance measurements in ERT based damage detection. PMID:28772485

  2. Fuzzy Random λ-Mean SAD Portfolio Selection Problem: An Ant Colony Optimization Approach

    Science.gov (United States)

    Thakur, Gour Sundar Mitra; Bhattacharyya, Rupak; Mitra, Swapan Kumar

    2010-10-01

    To reach the investment goal, one has to select a combination of securities among different portfolios containing large number of securities. Only the past records of each security do not guarantee the future return. As there are many uncertain factors which directly or indirectly influence the stock market and there are also some newer stock markets which do not have enough historical data, experts' expectation and experience must be combined with the past records to generate an effective portfolio selection model. In this paper the return of security is assumed to be Fuzzy Random Variable Set (FRVS), where returns are set of random numbers which are in turn fuzzy numbers. A new λ-Mean Semi Absolute Deviation (λ-MSAD) portfolio selection model is developed. The subjective opinions of the investors to the rate of returns of each security are taken into consideration by introducing a pessimistic-optimistic parameter vector λ. λ-Mean Semi Absolute Deviation (λ-MSAD) model is preferred as it follows absolute deviation of the rate of returns of a portfolio instead of the variance as the measure of the risk. As this model can be reduced to Linear Programming Problem (LPP) it can be solved much faster than quadratic programming problems. Ant Colony Optimization (ACO) is used for solving the portfolio selection problem. ACO is a paradigm for designing meta-heuristic algorithms for combinatorial optimization problem. Data from BSE is used for illustration.

  3. A fast inverse treatment planning strategy facilitating optimized catheter selection in image-guided high-dose-rate interstitial gynecologic brachytherapy.

    Science.gov (United States)

    Guthier, Christian V; Damato, Antonio L; Hesser, Juergen W; Viswanathan, Akila N; Cormack, Robert A

    2017-12-01

    Interstitial high-dose rate (HDR) brachytherapy is an important therapeutic strategy for the treatment of locally advanced gynecologic (GYN) cancers. The outcome of this therapy is determined by the quality of dose distribution achieved. This paper focuses on a novel yet simple heuristic for catheter selection for GYN HDR brachytherapy and their comparison against state of the art optimization strategies. The proposed technique is intended to act as a decision-supporting tool to select a favorable needle configuration. The presented heuristic for catheter optimization is based on a shrinkage-type algorithm (SACO). It is compared against state of the art planning in a retrospective study of 20 patients who previously received image-guided interstitial HDR brachytherapy using a Syed Neblett template. From those plans, template orientation and position are estimated via a rigid registration of the template with the actual catheter trajectories. All potential straight trajectories intersecting the contoured clinical target volume (CTV) are considered for catheter optimization. Retrospectively generated plans and clinical plans are compared with respect to dosimetric performance and optimization time. All plans were generated with one single run of the optimizer lasting 0.6-97.4 s. Compared to manual optimization, SACO yields a statistically significant (P ≤ 0.05) improved target coverage while at the same time fulfilling all dosimetric constraints for organs at risk (OARs). Comparing inverse planning strategies, dosimetric evaluation for SACO and "hybrid inverse planning and optimization" (HIPO), as gold standard, shows no statistically significant difference (P > 0.05). However, SACO provides the potential to reduce the number of used catheters without compromising plan quality. The proposed heuristic for needle selection provides fast catheter selection with optimization times suited for intraoperative treatment planning. Compared to manual optimization, the

  4. Fluorinated arene, imide and unsaturated pyrrolidinone based donor acceptor conjugated polymers: Synthesis, structure-property and device studies

    Science.gov (United States)

    Liyanage, Arawwawala Don Thilanga

    After the discovery of doped polyacetylene, organic semiconductor materials are widely studied as high impending active components in consumer electronics. They have received substantial consideration due to their potential for structural tailoring, low cost, large area and mechanically flexible alternatives to common inorganic semiconductors. To acquire maximum use of these materials, it is essential to get a strong idea about their chemical and physical nature. Material chemist has an enormous role to play in this novel area, including development of efficient synthetic methodologies and control the molecular self-assembly and (opto)-electronic properties. The body of this thesis mainly focuses on the substituent effects: how different substituents affect the (opto)-electronic properties of the donor-acceptor (D-A) conjugated polymers. The main priority goes to understand, how different alkyl substituent effect to the polymer solubility, crystallinity, thermal properties (e.g.: glass transition temperature) and morphological order. Three classes of D-A systems were extensively studied in this work. The second chapter mainly focuses on the synthesis and structure-property study of fluorinated arene (TFB) base polymers. Here we used commercially available 1,4-dibromo-2,3,5,6-tetrafluorobenzene (TFB) as the acceptor material and prepare several polymers using 3,3'-dialkyl(3,3'-R2T2) or 3,3'-dialkoxy bithiophene (3,3'-RO2T2) units as electron donors. A detail study was done using 3,3'-bithiophene donor units incorporating branched alkoxy-functionalities by systematic variation of branching position and chain length. The study allowed disentangling the branching effects on (i) aggregation tendency, intermolecular arrangement, (iii) solid state optical energy gaps, and (iv) electronic properties in an overall consistent picture, which might guide future polymer synthesis towards optimized materials for opto-electronic applications. The third chapter mainly focused on

  5. Analysis of multicriteria models application for selection of an optimal artificial lift method in oil production

    Directory of Open Access Journals (Sweden)

    Crnogorac Miroslav P.

    2016-01-01

    Full Text Available In the world today for the exploitation of oil reservoirs by artificial lift methods are applied different types of deep pumps (piston, centrifugal, screw, hydraulic, water jet pumps and gas lift (continuous, intermittent and plunger. Maximum values of oil production achieved by these exploitation methods are significantly different. In order to select the optimal exploitation method of oil well, the multicriteria analysis models are used. In this paper is presented an analysis of the multicriteria model's application known as VIKOR, TOPSIS, ELECTRE, AHP and PROMETHEE for selection of optimal exploitation method for typical oil well at Serbian exploration area. Ranking results of applicability of the deep piston pumps, hydraulic pumps, screw pumps, gas lift method and electric submersible centrifugal pumps, indicated that in the all above multicriteria models except in PROMETHEE, the optimal method of exploitation are deep piston pumps and gas lift.

  6. Seleção de doador de medula óssea ou sangue periférico Bone marrow or peripheral blood donor selection

    Directory of Open Access Journals (Sweden)

    Noemi F. Pereira

    2010-05-01

    Full Text Available A compatibilidade HLA é o fator mais valorizado na escolha do doador de medula óssea voluntário, preconizando-se a realização de HLA de alta resolução nos locos HLA-A,B,C, DRB1 e DQB1. Tem sido dado preferência para o doador com consanguinidade alélica 8x8 (A,B,C, DRB1. Na presença de incompatibilidade na classe-I sugere-se a busca de doador com compatibilidade DQB1 (9x10. Já as incompatibilidades dos locos DPB1 não constituem critério de exclusão de doador, exceto quando existir presença de anticorpo contra o loco HLA-DP do doador.The HLA system is considered the most important factor in choosing a volunteer bone marrow donor with the recommendation of performing high resolution HLA tests for the HLA-A, B, C, DRB1 and DQB1 loci. A preference has been given for donor 8x8 (A, B, C, DRB1 allele matching. In the presence of class-I incompatibility a search for DQB1 (9x10 donor compatibility is suggested. The incompatibility of the DPB1 locus does not constitute exclusion of the donor, except when there is the presence of antibodies against the HLA-DP locus of the donor.

  7. A Model of Donor Behaviour in the Czech Republic

    Directory of Open Access Journals (Sweden)

    Marie Hladká

    2017-06-01

    Full Text Available The article examines the variables underlying an individual’s decision to donate money to a nonprofit organisation. Based on a  content analysis of leading foreign research, we identify and systematise factors that may affect an individual’s decision to donate money, and we carry out an empirical testing in the Czech Republic. This article presents answers to the following question: which determinants affect significantly the willingness to donate? What does the model of donor behaviour look like on a selected sample? The authors apply a theoretical justification set of variables affecting donor behaviour to a  questionnaire survey. Multiple linear regression analysis and binary logistic regression are used to determine which of the variables is the most influential. Among the statistically significant variables we can include: respondent’s income, age, relations with the organisation and employees, the final beneficiary, religious orientation, affection, compassion and solidarity, gratitude, social responsibility and moral obligation, self-centred, feel good, pity, faith in justice.

  8. On the non-contractual nature of donor-recipient interaction in development assistance

    OpenAIRE

    Murshed, S. Mansoob

    2008-01-01

    This paper analyses three issues in strategic donor-recipient interaction motivated by the complexity of the rationale underlying aid. The first is when we have several principals with conflicting objectives. Any one principal cannot offer high powered incentives to the agent to carry out their designated task. The second is to do with the fact that effort associated with ensuring aid effectiveness may concern both principal and agent; the optimal solution to which requires difficult to desig...

  9. Validation of systems biology derived molecular markers of renal donor organ status associated with long term allograft function.

    Science.gov (United States)

    Perco, Paul; Heinzel, Andreas; Leierer, Johannes; Schneeberger, Stefan; Bösmüller, Claudia; Oberhuber, Rupert; Wagner, Silvia; Engler, Franziska; Mayer, Gert

    2018-05-03

    Donor organ quality affects long term outcome after renal transplantation. A variety of prognostic molecular markers is available, yet their validity often remains undetermined. A network-based molecular model reflecting donor kidney status based on transcriptomics data and molecular features reported in scientific literature to be associated with chronic allograft nephropathy was created. Significantly enriched biological processes were identified and representative markers were selected. An independent kidney pre-implantation transcriptomics dataset of 76 organs was used to predict estimated glomerular filtration rate (eGFR) values twelve months after transplantation using available clinical data and marker expression values. The best-performing regression model solely based on the clinical parameters donor age, donor gender, and recipient gender explained 17% of variance in post-transplant eGFR values. The five molecular markers EGF, CD2BP2, RALBP1, SF3B1, and DDX19B representing key molecular processes of the constructed renal donor organ status molecular model in addition to the clinical parameters significantly improved model performance (p-value = 0.0007) explaining around 33% of the variability of eGFR values twelve months after transplantation. Collectively, molecular markers reflecting donor organ status significantly add to prediction of post-transplant renal function when added to the clinical parameters donor age and gender.

  10. A hybrid agent-based computational economics and optimization approach for supplier selection problem

    Directory of Open Access Journals (Sweden)

    Zahra Pourabdollahi

    2017-12-01

    Full Text Available Supplier evaluation and selection problem is among the most important of logistics decisions that have been addressed extensively in supply chain management. The same logistics decision is also important in freight transportation since it identifies trade relationships between business establishments and determines commodity flows between production and consumption points. The commodity flows are then used as input to freight transportation models to determine cargo movements and their characteristics including mode choice and shipment size. Various approaches have been proposed to explore this latter problem in previous studies. Traditionally, potential suppliers are evaluated and selected using only price/cost as the influential criteria and the state-of-practice methods. This paper introduces a hybrid agent-based computational economics and optimization approach for supplier selection. The proposed model combines an agent-based multi-criteria supplier evaluation approach with a multi-objective optimization model to capture both behavioral and economical aspects of the supplier selection process. The model uses a system of ordered response models to determine importance weights of the different criteria in supplier evaluation from a buyers’ point of view. The estimated weights are then used to calculate a utility for each potential supplier in the market and rank them. The calculated utilities are then entered into a mathematical programming model in which best suppliers are selected by maximizing the total accrued utility for all buyers and minimizing total shipping costs while balancing the capacity of potential suppliers to ensure market clearing mechanisms. The proposed model, herein, was implemented under an operational agent-based supply chain and freight transportation framework for the Chicago Metropolitan Area.

  11. Expectations and experiences of gamete donors and donor-conceived adults searching for genetic relatives using DNA linking through a voluntary register.

    Science.gov (United States)

    van den Akker, O B A; Crawshaw, M A; Blyth, E D; Frith, L J

    2015-01-01

    What are the experiences of donor-conceived adults and donors who are searching for a genetic link through the use of a DNA-based voluntary register service? Donor-conceived adults and donors held positive beliefs about their search and although some concerns in relation to finding a genetically linked relative were reported, these were not a barrier to searching. Research with donor-conceived people has consistently identified their interest in learning about-and in some cases making contact with-their donor and other genetic relatives. However, donor-conceived individuals or donors rarely have the opportunity to act on these desires. A questionnaire was administered for online completion using Bristol Online Surveys. The survey was live for 3 months and responses were collected anonymously. The survey was completed by 65 donor-conceived adults, 21 sperm donors and 5 oocyte donors who had registered with a DNA-based voluntary contact register in the UK. The questionnaire included socio-demographic questions, questions specifically developed for the purposes of this study and the standardized Aspects of Identity Questionnaire (AIQ). Motivations for searching for genetic relatives were varied, with the most common reasons being curiosity and passing on information. Overall, participants who were already linked and those awaiting a link were positive about being linked and valued access to a DNA-based register. Collective identity (reflecting self-defining feelings of continuity and uniqueness), as assessed by the AIQ, was significantly lower for donor-conceived adults when compared with the donor groups (P 0.05) for donor-conceived adults. Participants were members of a UK DNA-based registry which is unique. It was therefore not possible to determine how representative participants were of those who did not register for the service, those in other countries or of those who do not seek information exchange or contact. This is the first survey exploring the

  12. Hilar control during laparoscopic donor nephrectomy: Practice patterns in Canada.

    Science.gov (United States)

    Mcgregor, Thomas B; Patel, Premal; Chan, Gabriel; Sener, Alp

    2017-10-01

    In recent years, the method of vascular control during laparoscopic donor nephrectomy (LDN) has come under scrutiny due to catastrophic consequences of a device failure. This study sought to examine the surgical preferences of Canadian donor surgeons with regards to vascular control and their perception on the safety of these modalities. We also surveyed the experience with device malfunction and their subsequent management during LDN. An online survey was sent out to donor surgeons registered with the Canadian Society of Transplantation. Surveys were anonymous and voluntary. Descriptive statistics were used to analyze the collected responses. Recollection of the sequelae and outcomes from device malfunction were also queried. Twenty-eight of 37 surgeons (76% response rate) responded to the survey. At least one surgeon from every institution in Canada performing LDN responded to the survey. Laparoscopic stapler is the most commonly used device for securing the renal artery (61%) and renal vein (67%). Overall, surgeons felt the stapler was the safest method of securing the renal artery. Stapler misfire and clip slippage were reported by eight (28.5%) and 12 (43%) surgeons, respectively. Most cases were salvageable: laparoscopically (30%), open conversion (30%), and by hand port (5%). Slippage of a plastic locking clip resulted in one emergent laparotomy on POD#1 and one stapler misfire was converted to open resulting in donor death. Although rare, hemorrhagic complications can occur from device malfunction resulting in poor outcomes for healthy volunteers undergoing LDN. Surgeons need to remain vigilant when selecting the appropriate modality for vascular control.

  13. A New Methodology to Select the Preferred Solutions from the Pareto-optimal Set: Application to Polymer Extrusion

    International Nuclear Information System (INIS)

    Ferreira, Jose C.; Gaspar-Cunha, Antonio; Fonseca, Carlos M.

    2007-01-01

    Most of the real world optimization problems involve multiple, usually conflicting, optimization criteria. Generating Pareto optimal solutions plays an important role in multi-objective optimization, and the problem is considered to be solved when the Pareto optimal set is found, i.e., the set of non-dominated solutions. Multi-Objective Evolutionary Algorithms based on the principle of Pareto optimality are designed to produce the complete set of non-dominated solutions. However, this is not allays enough since the aim is not only to know the Pareto set but, also, to obtain one solution from this Pareto set. Thus, the definition of a methodology able to select a single solution from the set of non-dominated solutions (or a region of the Pareto frontier), and taking into account the preferences of a Decision Maker (DM), is necessary. A different method, based on a weighted stress function, is proposed. It is able to integrate the user's preferences in order to find the best region of the Pareto frontier accordingly with these preferences. This method was tested on some benchmark test problems, with two and three criteria, and on a polymer extrusion problem. This methodology is able to select efficiently the best Pareto-frontier region for the specified relative importance of the criteria

  14. [Donor supply of scalp and specificities of hair transplantation in Asians].

    Science.gov (United States)

    Tsilosani, A Z; Mshvenieradze, E G

    2008-01-01

    In 2005--2007 in a hair transplantation clinic 'Talizi' the flow of international patients increased dramatically, including those from Central and Eastern Asia. During this period 211 ethnic Asian patients underwent operations, including 146 patients from South Korea, 2--from China, 62-- from Kazakhstan and 1--from Philippines. Black and straight hair give impact of low density due to considerable contrast with characteristic for Asians light color scalp; therefore, from the very beginning we tried to transplant as many grafts (follicular units - FU) as possible. For the operation we chose strip version (FUSS) that enables to receive large number of grafts. The scale of transplantation varied in a range of 1200-3800 FU, on average--2500-3000 FU. Though, even from the very first cases we faced specificities of ethnic Asian scalp that significantly complicated our work: low density and low hair/graft ratio in donor zone in contrast to information from special literature, and low laxity (flexibility) of the scalp. We set an objective to specify indicators of donor density (number of FU on a sq.cm and hair/FU ratio), to study bio-mechanical specificities of ethnic Asian scalp and develop optimal surgical tactics for these patients after the evaluation of transplantation results. Observation group was composed of 211 patients from abovementioned countries and a sub-group--50 Korean patients for medium-scale hair transplantation (2000-3000 FU) by strip version. Study of donor characteristics of these patients revealed low density--74 FU/cm2; on 1 cm2 grow only 121 hairs, whereas hair/FU ration was 1,63. Strength required to close would edges (scalp tension power) varied from 1,4 kg-f to 2,6 kg-f depending on scalp flexibility and number of transplanted grafts (strip width), and amounted on average to 2,16 +/- 0,02 kg-f, p flexibility of the scalps this resulted in high percentage (10-15%) of wide (4-10 mm) scar formation in donor area. In order to find the way out from

  15. An ant colony optimization based feature selection for web page classification.

    Science.gov (United States)

    Saraç, Esra; Özel, Selma Ayşe

    2014-01-01

    The increased popularity of the web has caused the inclusion of huge amount of information to the web, and as a result of this explosive information growth, automated web page classification systems are needed to improve search engines' performance. Web pages have a large number of features such as HTML/XML tags, URLs, hyperlinks, and text contents that should be considered during an automated classification process. The aim of this study is to reduce the number of features to be used to improve runtime and accuracy of the classification of web pages. In this study, we used an ant colony optimization (ACO) algorithm to select the best features, and then we applied the well-known C4.5, naive Bayes, and k nearest neighbor classifiers to assign class labels to web pages. We used the WebKB and Conference datasets in our experiments, and we showed that using the ACO for feature selection improves both accuracy and runtime performance of classification. We also showed that the proposed ACO based algorithm can select better features with respect to the well-known information gain and chi square feature selection methods.

  16. Cancer risk in children born after donor ART.

    Science.gov (United States)

    Williams, C L; Bunch, K J; Murphy, M F G; Stiller, C A; Botting, B J; Wallace, W H; Davies, M C; Sutcliffe, A G

    2018-01-01

    Do children born after donor ART have an increased risk of developing childhood cancer in comparison to the general population? This study showed no overall increased risk of childhood cancer in individuals born after donor ART. Most large population-based studies have shown no increase in overall childhood cancer incidence after non-donor ART; however, other studies have suggested small increased risks in specific cancer types, including haematological cancers. Cancer risk specifically in children born after donor ART has not been investigated to date. This retrospective cohort study utilized record linkage to determine the outcome status of all children born in Great Britain (1992-2008) after donor ART. The cohort included 12 137 members who contributed 95 389 person-years of follow-up (average follow-up 7.86 years). Records of all children born in Great Britain (England, Wales, Scotland) after all forms of donor ART (1992-2008) were linked to the UK National Registry of Childhood Tumours (NRCT) to determine the number who subsequently developed cancer by 15 years of age, by the end of 2008. Rates of overall and type specific cancer (selected a priori) were compared with age, sex and calendar year standardized population-based rates, stratifying for potential mediating/moderating factors including sex, age at diagnosis, birth weight, multiple births, maternal previous live births, assisted conception type and fresh/ cryopreserved cycles. In our cohort of 12 137 children born after donor ART (52% male, 55% singleton births), no overall increased risk of cancer was identified. There were 12 cancers detected compared to 14.4 expected (standardized incidence ratio (SIR) 0.83; 95% CI 0.43-1.45; P = 0.50). A small, significant increased risk of hepatoblastoma was found, but the numbers and absolute risks were small (ART, the rarity of specific diagnostic subgroups of childhood cancer results in few cases and therefore wide CIs for such outcomes. As this is an

  17. True HIV seroprevalence in Indian blood donors.

    Science.gov (United States)

    Choudhury, N; Ayagiri, A; Ray, V L

    2000-03-01

    The National AIDS Control Organization (NACO), the apex body for controlling AIDS in India, projected that HIV seroprevalence would increase from 7/1000 in 1995 to 21.2/1000 in 1997. A high incidence (8.2%) of HIV was observed in blood donors. This study was carried out to find out the true HIV positivity in Indian blood donors. Blood donors from our centre were followed for more than 5 years to determine the true HIV seroprevalence and our result was compared with similar studies from India. Voluntary and relative blood donors who visited the SGPGIMS, Lucknow, since 1993 to June 1998 were included. They were screened for HIV 1/2 by ELISA kits (WHO approved). First-time HIV-positive samples were preserved frozen for further study (stage-I). They were repeated in duplicate and retested with other kits. If found positive, the sample was labelled as ELISA positive (stage-II). ELISA-positive samples were confirmed by Western Blot (WB) at stage-III. A total of 65 288 donors were included and 834 (12.8/1000) were reactive at stage-I. But 1.1/1000 donors were found to be ELISA positive at stage-II, and 0.28/1000 donors were positive by WB at stage-III. The 'seropositivity' rate from the NACO was significantly (P commercial blood banks. The HIV prevalence of blood donors (and national prevalence) is to be reassessed.

  18. Anesthesia Management of Organ Donors.

    Science.gov (United States)

    Xia, Victor W; Braunfeld, Michelle

    2017-09-01

    The shortage of suitable organs is the biggest obstacle for transplants. At present, most organs for transplant in the United States are from donation after neurologic determination of death (brain death). Potential organs for transplant need to maintain their viability during a series of insults, including the original disease, physiologic derangements during the dying process, ischemia, and reperfusion. Proper donor management before, during, and after procurement has potential to increase the number and quality of organs from donors. Anesthesiologists need to understand the physiologic derangements associated with brain death and the updated donor management during the periprocurement period. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Live donor transplantation--the incompetent donor: comparative law.

    Science.gov (United States)

    Wolfman, Samuel; Shaked, Tali

    2008-12-01

    Informed consent of the patient to medical treatment is an essential prerequisite for any invasive medical procedure. However in emergency cases, when the patient is unable to sign a consent form due to unconsciousness or to psychotic state, than the primary medical consideration shall take place. In such a case, in order to save life or even prevent a major medical hazard to the patient, doctors are allowed, in certain cases and in accordance with well accepted medical practice, to perform invasive procedures, major surgery or risky pharmacological treatment, without the explicit consent of the patient. All the above refers to the cases when avoidance of such non-consented treatment may harm severely the health and wellbeing of the patient and there is no doubt that such treatment is for the ultimate benefit of the patient. The question, however, shall arise when such a medical procedure is not necessarily for the benefit of the patient, but rather for the benefit of somebody else. Such is the case in the transplantation area and the question of living donor-donee relationship. This paper shall analyze the legal situation in cases of non competent donors whose consent cannot be considered legal consent given in full understanding and out of free will. It will also compare three legal systems, the Israeli, the American and the traditional Jewish law, with regard to the different approaches to this human problem, where the autonomy of the donor may be sacrificed for the purpose of saving life of another person.

  20. Factors affecting the serological testing of cadaveric donor cornea.

    Science.gov (United States)

    Raj, Anuradha; Mittal, Garima; Bahadur, Harsh

    2018-01-01

    The purpose of this study was to evaluate the serological profile of the eye donors and to study the influence of various factors on serological test results. A cross-sectional, observational study was conducted, and data of 509 donors were reviewed from the records of eye bank from December 2012 to June 2017. Various details of donors analyzed included the age, sex of the donor, cause of death, source of tissue, time since blood collection after death, macroscopic appearance of blood sample, and details of discarded tissues. Serological examination of blood was performed for human immunodeficiency virus (HIV), hepatitis B virus, hepatitis C virus (HCV), venereal disease research laboratory (VDRL), and serology reports reactive or nonreactive were analyzed. Among the 509 donors, 295 (58%) were male, and 420 (82.50%) belonged to age group ≥60 years. Most donors (354, 69.5%) died due to cardiac arrest. Macroscopically, sera were normal in the majority of 488 (95.9%) cases. Among 509 donors, 475 (93.3%) were nonreactive, 12 (2.4%) donors were found to be reactive to hepatitis B surface antigen (HBsAg), and 1 (0.2%) was reactive to HCV, but no donor serology was reactive to HIV or VDRL. Twenty-one (4.12%) donors' sera were not fit for serological testing. Among all donors, 475 (93.32%) donors were accepted and 34 (6.67%) were rejected or discarded on the basis of serological testing. Cause of death and macroscopic aspect of sera influenced the serological results in a highly significant manner (P = 0.00). Acceptance or rejection of the donor was significantly influenced by the serological results of the donor (P = 0.00). The seroprevalence among eye donor for HBsAg and HCV was 12 (2.4%) and 1 (0.2%), respectively. Factors such as cause of death and macroscopic aspect of sera influence the serological results. Time since blood collection or sampling will not show any impact on viral serological results if postmortem sampling will be done in donor cornea.

  1. Analysis Methodology for Optimal Selection of Ground Station Site in Space Missions

    Science.gov (United States)

    Nieves-Chinchilla, J.; Farjas, M.; Martínez, R.

    2013-12-01

    Optimization of ground station sites is especially important in complex missions that include several small satellites (clusters or constellations) such as the QB50 project, where one ground station would be able to track several spatial vehicles, even simultaneously. In this regard the design of the communication system has to carefully take into account the ground station site and relevant signal phenomena, depending on the frequency band. To propose the optimal location of the ground station, these aspects become even more relevant to establish a trusted communication link due to the ground segment site in urban areas and/or selection of low orbits for the space segment. In addition, updated cartography with high resolution data of the location and its surroundings help to develop recommendations in the design of its location for spatial vehicles tracking and hence to improve effectiveness. The objectives of this analysis methodology are: completion of cartographic information, modelling the obstacles that hinder communication between the ground and space segment and representation in the generated 3D scene of the degree of impairment in the signal/noise of the phenomena that interferes with communication. The integration of new technologies of geographic data capture, such as 3D Laser Scan, determine that increased optimization of the antenna elevation mask, in its AOS and LOS azimuths along the horizon visible, maximizes visibility time with spatial vehicles. Furthermore, from the three-dimensional cloud of points captured, specific information is selected and, using 3D modeling techniques, the 3D scene of the antenna location site and surroundings is generated. The resulting 3D model evidences nearby obstacles related to the cartographic conditions such as mountain formations and buildings, and any additional obstacl