An investigation into algorithms for the optimal discount assignment problem in E-commerce

Celem niniejszej pracy jest zaproponowanie algorytmu rozwiązującego problem optymalnego przydziału konfliktujących zniżek promocyjnych i wykonanie bazowej implementacji. Celem biznesowym jest znalezienie metody konstruowania konfliktujących promocji w taki sposób, aby problem przydziału mógł być efektywnie rozwiązany.Pokazujemy, że opisany problem redukuje się do programowania liniowego całkowitoliczbowego (ILP) oraz proponujemy rozwiązanie w języku Java oparte o interfejs do solverów ILP. Przedstawiamy również autorski algorytm zachłanny rozwiązujący ograniczoną wersję problemu. Praca powstała przy współudziale Ocado Technology, oddziału IT największego brytyjskiego supermarketu online.The aim of this thesis is to propose an algorithm for the optimal conflicting discount assignment problem and to create its basic implementation. The business purpose is to find a way of constructing conflicting discounts such that the assignment problem can be effectively solved. We show that the problem at hand reduces to Integer Linear Programming (ILP) and propose a solution implemented in Java programming language using an unified interface for various ILP solvers. We also present our own greedy algorithm for solving a restricted version of the problem. The project was led by Ocado Technology, the IT division of the largest British online supermarket

Economic and Ecological Assessment of Transport of Various Types of Waste

The amount of generated waste has been increasing for several years in Poland. There is a lot of research in the field of the environmental and economic evaluation of waste treatment processes. Waste transport is considered to be one of the most important elements of waste management (WM), because it integrates the whole WM system. The environmental impact of waste transport is rising (emissions to air). The European Union introduced provisions on the principle of proximity in the Waste Framework Directive. This principle suggests that waste should generally be transported, treated or disposed of as near to its place of origin as possible. The main aim of the study was to perform an ecological and technical-economic analysis of transportation of selected types of waste (mixed municipal solid waste, construction and demolition waste, separately collected waste called: segregation). The research applied data obtained from a municipal enterprise operating in the South Poland. SimaPro 8.1 software with Ecoinvent 3.3 database was employed to calculate the environmental impact. As a result of the analysis, it was found that the transportation of 1 Mg construction waste had twice as much negative impact on the environment as transportation of 1 Mg mixed municipal waste and segregated waste. This is connected with higher fuel consumption per 1 Mg of transported construction waste and twice the distance that an average hooklift truck must cover in order to collect 1 Mg of construction waste

Ocena progresji neoaterosklerozy po 3 i 9 latach od implantacji stentów uwalniających sirolimus i paklitaksel z wykorzystaniem optycznej koherentnej tomografii.

Background: Early-generation drug-eluting stents (DESs) have been shown to accelerate neoatherogenesis. Limited optical coherence tomography (OCT) data on the very long-term neoatherosclerotic progression after DES implantation are available. Aim: The aim of this study was a serial OCT evaluation of neoatherosclerosis at three and nine years after implantation of sirolimus-eluting stents (SESs) and paclitaxel-eluting stents (PESs). Methods: Consecutive patients undergoing elective percutaneous coronary intervention with SES (Cypher, Cordis) or PES (Taxus, Boston Scientific) were included in this single-centre, longitudinal study. OCT analysis was performed after three and nine years by an independent core laboratory. Results: A total of 39 OCT recordings were assessed at three years after the index procedure; of them, 22 (eight SES and 14 PES) OCT pullbacks were evaluated in a paired analysis at three and nine years post implantation. Overall, neoatheroscle­rosis was identified in 23.1% of stents at three years and in 30.8% at nine years after the index procedure (p = 0.289). No features of significant neoatherosclerotic progression were found in either group between three- and nine-year assessment. Conclusions: At nine years after implantation of early-generation DES no significant neoatherosclerotic progression was observed among patients with uneventful follow-up at three years after PCI, as assessed by OCT. These observations need to be confirmed in larger studies including the current generation of DESs.Wstęp Stenty uwalniające lek wczesnej generacji zwiększają ryzyko neoaterosklerozy - nowych zmian miażdżycowych w obrębie neointimy. Dane dotyczące bardzo odległej analizy proliferacji neointimy ocenianej za pomocą optycznej koherentnej tomografii (OCT) po implantacji stentów uwalniających lek są ograniczone. Cel Celem badania była ocena zjawiska neoaterosklerozy 3 i 9 lat po implanatcji stentów uwalniających sirolimus (SES) oraz stentów uwalniających paklitaksel (PES). Metody i wyniki Badanie miało charakter obserwacyjny i jednoośrodkowy. Do analizy włączono pacjentów poddanych planowym zabiegom przezskórnych interwencji wieńcowych z implantacją SES (Cypher, Cordis) lub PES (Taxus, Boston Scientific). Analiza obrazów uzyskanych za pomocą OCT była przeprowadzona po 3 i 9 latach od zabiegu przez niezależne laboratorium analizy obrazów OCT. Łącznie 39 obrazów OCT zostało ocenionych 3 lata po zabiegu, wśród których 22 (8 SES i 14 PES) było poddanych powiązanej analizie 3 i 9 lat po zabiegu. Zjawisko neoaterosklerozy zaobserowano w 23,1% stentów 3 lata po zabiegu oraz w 30,8% 9 lat po zabiegu (p=0,289). Nie zanotowano znaczących różnic w progresji zmian w obu grupach w analizie 3- i 9-letniej. Wnioski W analizie 9-letniej po implantacji stentów uwalniających lek wczesnej generacji nie zaobserwowano progresji zmian neoaterosklerotycznych wśród pacjentów z niepowikłanym 3–letnim okresem obserwacji ocenianym za pomocą OCT

OCT-Derived Plaque Morphology and FFR-Determined Hemodynamic Relevance in Intermediate Coronary Stenoses

Background: optical coherence tomography (OCT) might allow identifying lesion features reportedly associated with plaque vulnerability and increased risk of clinical events. Previous studies on correlation between OCT and functional lesion significance indices reported contradictory results, yet integration of complementary information from both modalities is gaining increased interest. The aim of the study was to compare plaque morphology using OCT in hemodynamically relevant vs. non-relevant lesions by fractional flow reserve (FFR). Methods: consecutive patients with intermediate grade coronary stenoses by angiography were evaluated by both FFR and OCT in this single-center study. Stenoses were labeled hemodynamically relevant in case of the FFR ≤ 0.80. Minimal lumen area (MLA), fibrous cap thickness (FCT), minimal cap thickness over the calcium, angle of the calcium, and necrotic core within the lesions were evaluated. Results: a total of 105 patients (124 vessels) were analyzed. Of them, 65 patients were identified with at least one lesion identified as hemodynamically relevant by FFR (72 vessels, 58.1%). Lesions with FFR ≤0.80 presented with lower mean and minimal lumen area (3.46 ± 1.29 vs. 4.65 ± 2.19, p =0.001 and 1.84 ± 0.97 vs. 2.66 ± 1.40, p = 0.001) compared to patients with FFR > 0.80. No differences were found between groups in the mean and minimal FCT, mean, and maximal necrotic core, calcium angle, as well as the overall rate of calcified and lipid plaques. Conclusion: hemodynamic relevance of intermediate grade lesions correlated moderately with the luminal assessment by OCT. No differences were identified in the plaque morphology between relevant and non-relevant coronary stenoses by FFR

Does the KIR2DS5 gene protect from some human diseases?

BACKGROUND: KIR2DS5 gene encodes an activating natural killer cell receptor whose ligand is not known. It was recently reported to affect the outcome of hematopoietic stem cell transplantation. METHODOLOGY/PRINCIPAL FINDINGS: In our studies on KIR2DS5 gene associations with human diseases, we compared the frequencies of this gene in patients and relevant controls. Typing for KIR2DS5 gene was performed by either individual or multiplex polymerase chain reactions which, when compared in the same samples, gave concordant results. We noted an apparently protective effect of KIR2DS5 gene presence in several clinical conditions, but not in others. Namely, this effect was observed in ankylosing spondylitis (p=0.003, odds ratio [OR]=0.47, confidence interval [CI]=0.28-0.79), endometriosis (p=0.03, OR=0.25, CI = 0.07-0.82) and acute rejection of kidney graft (p=0.0056, OR=0.44, CI=0.24-0.80), but not in non-small-cell lung carcinoma, rheumatoid arthritis, spontaneous abortion, or leukemia (all p>0.05). In addition, the simultaneous presence of KIR2DS5 gene and HLA-C C1 allotype exhibited an even stronger protective effect on ankylosing spondylitis (p=0.0003, OR=0.35, CI=0.19-0.65), whereas a lack of KIR2DS5 and the presence of the HLA-C C2 allotype was associated with ankylosing spondylitis (p=0.0017, OR=1.92, CI=1.28-2.89), whereas a lack of KIR2DS5 and presence of C1 allotype was associated with rheumatoid arthritis (p=0.005, OR=1.47, CI=1.13-1.92). The presence of both KIR2DS5 and C1 seemed to protect from acute kidney graft rejection (p=0.017, OR=0.47, CI=0.25-0.89), whereas lack of KIR2DS5 and presence of C2 seemed to favor rejection (p=0.0015, OR=2.13, CI=1.34-3.37). CONCLUSIONS/SIGNIFICANCE: Our results suggest that KIR2DS5 may protect from endometriosis, ankylosing spondylitis, and acute rejection of kidney graft