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The problem studied in this article arises from the distribution of soft drinks and collection of recyclable containers in a Quebec-based company. It can be modelled as a variant of the vehicle routing problem with a heterogeneous vehicle fleet, time windows, capacity and volume constraints, and an objective function combining routing costs and the revenue resulting from the sale of recyclable material. Three construction heuristics and an improvement procedure are developed for the problem. Comparative tests are performed on a real-life instance and on 10 randomly generated instances. doi: 10.1057/palgrave.jors.2602087 Published online 19 October 2005 Keywords: heterogeneous vehicle routing problem; time windows; soft-drink distribution; reverse logistics; heuristics

This paper considers the problem of coordinated ordering of items having deterministic but time-varying demands where there is a common ordering cost if one or more of these items are ordered in addition to individual items ordering costs. Two new integer linear-programming formulations are presented and compared with the classical formulation. Several well-known heuristics are described and a new improvement procedure is proposed. The relative performance of these heuristics is assessed. Results show the superiority of the new formulations and of the new improvement procedure. [ABSTRACT FROM AUTHOR]

The problem of sequencing, lot sizing and scheduling a number of products in flow shops has been studied by several authors. It has been reported by some of them that the sequence to be used has a negligible impact on total cost. Consequently, little attention was given to the sequencing sub-problem. The purpose of this paper is to study the impact of sequencing decisions and to suggest some methods to determine the sequence to be used. We propose a mathematical programming based heuristic as well as some construction and local search heuristics. The proposed heuristics are compared and computational results for 360 test problems are reported. These results reveal that sequencing decisions may have a non-negligible impact on total cost and may allow us to identify the best among the heuristics tested. [ABSTRACT FROM AUTHOR]

This paper deals with the multi-product, finite horizon, static demand, sequencing, lot sizing and scheduling problem in a job shop environment where the objective is to minimize the sum of setup and inventory holding costs while satisfying the demand with no backlogging. To solve this problem, we assume a common cycle for all products and divide the planning horizon into an integer number of identical production cycles. The problem is formulated as a mixed non-linear program which simultaneously determines sequencing, lot sizing and scheduling decisions. Unfortunately, for medium or large problems, the solution of this model may require an excessive amount of computational time. To solve such problems, we propose an adaptation of the simulated annealing algorithm and a tabu search algorithm. Within these two methods, a neighbouring solution is obtained by altering the production sequence of one of the machines. The modified set of sequences is then used as an input to another mixed non-linear program to determine lot sizes and starting dates. Some computational results are given to help assess the performance of the proposed heuristics. [ABSTRACT FROM AUTHOR]

Research is presented describing the development of a nonlinear programming application to measure flow shop scheduling and economic lot sizing problems where there is more than one product.

Despite a progressive reduction in acute myocardial infarction mortality over the years, death related to ventricular free wall rupture has not changed. This is mostly related to the catastrophic presentation and death within minutes in the majority of these patients. Once rupture is suspected, bedside echocardiography should be performed immediately, followed by pericardiocentesis and repair of the rupture site as quickly as possible. Measures to prevent cardiac rupture include the administration of beta-blockers and angiotensin-converting enzyme inhibitors unless contraindications exist, and the avoidance of steroidal and nonsteroidal anti-inflammatory agents such as ibuprofen and indomethacin. [ABSTRACT FROM AUTHOR]

Context: The risk of acquiring babesiosis by blood transfusion is largely unknown since in areas where it is endemic it is often an asymptomatic infection.Objective: To investigate and treat a cluster of blood transfusion-associated babesiosis cases.Design: Case series and epidemiologic investigation.Setting: Urban inner-city hospital.Patients: Six persons who received Babesia microti-infected blood components from a donor.Main Outcome Measure: Diagnosis and successful therapy of babesiosis following transfusion.Results: Six individuals (1 adult, 1 child, and 4 neonates) were exposed to products from a single blood donation by an asymptomatic Babesia-infected donor. Three of the 6 exposed patients became parasitemic. Polymerase chain reaction testing, animal inoculation studies, and indirect immunofluorescent antibody testing were used to confirm the presence of Babesia microti in the donor's blood and to establish the presence of infection in 3 of the 6 recipients. The 3 infected recipients and 1 additional recipient were treated without incident.Conclusion: Physicians should consider babesiosis in the differential diagnosis of a febrile hemolytic disorder after blood transfusion. Prompt diagnosis is important since babesiosis is responsive to antibiotic therapy and, untreated, can be a fatal disease in certain risk groups. [ABSTRACT FROM AUTHOR]

A crude Schistosoma mansoni soluble worm antigen preparation (SWAP) was fractionated using an immunoaffinity column consisting of specific human anti-SWAP antibodies obtained from chronic S. mansoni-infected human sera and bound to CNBr-activated Sepharose 48. The chromatographic separation resulted in three fractions: the unbound material (FW), and the eluted antigens with glycine-HCl (F1) and glycine-HCI-NaCl (F2). Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) showed that the purified antigens F1 and F2 consisted of several bands when stained with Coomassie blue and silver stain, with molecular weights between 20 × 10³ and 200 × 10³. The F1 and F2 fractions in addition to FW and SWAP were used in an enzyme-linked immunosorbent assay (ELISA) to measure antibody levels in sera from schistosomiasis patients. Each individual serum assessed with the purified F2 antigen gave 100% positivity and three to four times higher optical density in comparison to SWAP with only 88% positivity. No detectable cross- reactive antibodies against F2 were found when a limited number of sera from filariasis, fascioliasis and trichinellosis patients were screened. Furthermore, F2 was also used and found to be more sensitive generally in detecting anti-adult worm antibodies than SWAP in recently schistosomiasis- infected persons. Thus, F2 appears to be a highly sensitive and specific reagent for the serodiagnosis of schistosomiasis infection. [ABSTRACT FROM AUTHOR]

Crude polysaccharide antigen was extracted from Schistosomu mansoni egg homogenate by 44% aqueous phenol. The aqueous soluble polysaccharide extract was subjected to affinity chromatography with concanavalin A-Sepharose 4B. Two fractions (bound and unbound) were obtained; both of them gave precipitin lines with serum obtained from mice infected with S. mansoni. These precipitin lines gave partial identity. Further fractionation with wheat germ agglutinin-sepharose of the unbound Fraction resulted in three antigenic fractions. These different antigens were eluted with different N-acetylglucosamine molarities (0, 0.0.5 and 0.5) and gave lines of identity when reacted against infected mouse serum. When the four antigenic materials were subjected to polyacrylamide gel electrophoresis and stained for proteins and polysaccharides no migration bands were observed. The chemical analysis of the two initial fractions showed a small percentage of amino acids in both fractions. Sugar analysis with gas-liquid chromatography showed different sugar composition of the two initial fractions. [ABSTRACT FROM AUTHOR]

We are describing the successful treatment of two cases of late Class II antibody mediated rejection status postkidney transplantation. The first patient was treated with a combination of plasmapheresis, intravenous immunoglobulin (IVIG), and stenting of the transplanted renal artery. The second was treated with IVIG and pulse steroids.

We analyzed our historic patient database at North Shore University Hospital and determined both the overall frequency of anti-Js(a) and the frequency at which it was detected in combination with other alloantibodies to red blood cell (RBC) antigens. Screening cells used currently are negative for Js(a). Our data suggest that anti-Js(a) would not be detected in 30 to 40 percent of patients in which it is the sole antibody present. Since 1996 the antibody was only detected when other antibodies were found in the screening process. We are exposing 1.7 percent of our patients (90 patients/year) to Js(a). The clinical significance of anti-Js(a) is apparent with previous literature, and our conclusion is that additional studies should be performed to determine whether Js(a) should be included in current antibody screening cells.

Wr(a) is a low-prevalence antigen. Anti-Wr(a) is a relatively common antibody present in approximately 1 in 100 healthy blood donors. Anti-Wr(a) is reported to cause different degrees of hemolysis in transfusion and in HDN, ranging from benign to severe. This report describes an acute overt hemolytic transfusion reaction in a patient whose serum contained anti-Wr(a) and who received a Wr(a+) RBC component.

Plasmapheresis (PP) and intravenous immunoglobulin (IVIg) remove donor-specific antibodies, a cause of acute humoral rejection (AHR). We describe the use of PP and IVIg as rescue therapy for AHR. The records of 143 renal transplants performed between October 1, 2000 and April 1, 2002 were reviewed. Patients who underwent PP and IVIg therapy for AHR were identified. The data reviewed included age, sex, source of transplant, number of human leukocyte antigen mismatches, transplant number, number of PP and IVIg treatments, dose of IVIg, time of AHR, serum creatinine (SCr) level at AHR, SCr level after PP and IVIg at 3 months, days to achieve 30% decline in SCr, and graft survival. Immunosuppression included basiliximab induction, tacrolimus, and prednisone (+/- sirolimus or mycophenolate mofetil [CellCept, Roche Pharmaceutical, Nutley, NJ]). PP was followed by IVIg infusion. Nine patients were treated for AHR with PP and IVIg. All nine patients demonstrated biopsy-proven AHR. One graft was lost. Mean 3-month and 1-year SCr levels were 1.9 and 1.8, respectively, in the remaining eight patients. AHR in renal transplantation can be effectively treated with PP and IVIg.