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The study aimed to investigate the antibacterial activity of Mustard (Brassica juncea) and Moringa (Moringa oleifera) leaf extracts and coagulant protein for their potential application in water treatment. Bacterial cell aggregation and growth kinetics studies were employed for thirteen bacterial strains with different concentrations of leaf extracts and coagulant protein. Moringa oleifera leaf extract (MOS) and coagulant protein showed cell aggregation against ten bacterial strains, whereas leaf extract alone showed growth inhibition of five bacterial strains for up to 6 h and five bacterial strains for up to 3 h. Brassica juncea leaf extract (BJS) showed growth inhibition for up to 6 h, and three bacterial strains showed inhibition for up to 3 h. The highest inhibition concentration with 2.5 mg/mL was 19 mm, and furthermore, the minimum inhibitory concentration (MIC) (0.5 mg/mL) and MBC (1.5 mg/mL) were determined to have a higher antibacterial effect for <3 KDa peptides. Based on LCMS analysis, napin was identified in both MOS and BJS; furthermore, the mode of action of napin peptide was determined on lipoprotein X complex (LpxC) and four-chained structured binding protein of bacterial type II topoisomerase (4PLB). The docking analysis has exhibited moderate to potent inhibition with a range of dock score −912.9 Kcal/mol. Thus, it possesses antibacterial-coagulant potential bioactive peptides present in the Moringa oleifera purified protein (MOP) and Brassica juncea purified protein (BJP) that could act as an effective antimicrobial agent to replace currently available antibiotics. The result implies that MOP and Brassica juncea purified coagulant (BJP) proteins may perform a wide degree of antibacterial functions against different pathogens.  相似文献   
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We study the problem of minimizing makespan in a two-machine job shop with unit processing time operations. An efficient algorithm with respect to a succinct encoding of the problem instances is proposed. The algorithm is an improvement of earlier algorithms proposed for the problem by Brucker [1,2], Hefetz and Adiri [7], and Timkovskiy [15]. The idea behind the algorithm has the potential of extension to job shops with parallel machines.This research is supported in part by NSERC Grants A4619, OGP0105675, OGP0104900, General Motors of Canada, and the Manufacturing Research Corporation of Ontario.  相似文献   
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We study the benefits of coordinated decision making in a supply chain consisting of a manufacturer, a distributor, and several retailers. The distributor bundles finished goods produced by the manufacturer and delivers them to the retailers to meet their demands. The distributor is responsible for managing finished goods inventory. An optimal production schedule of the manufacturer, if imposed on the distributor, may result in an increased inventory holding cost for the distributor. On the other hand, an optimal distribution schedule of the distributor, if imposed on the manufacturer, may result in an increased production cost for the manufacturer. In this paper we develop mathematical models for individual optimization goals of the two partners and compare the results of these models with the results obtained for a joint optimization model at the system level. We investigate the computational complexities of these scheduling problems. The experimental results indicate that substantial cost savings can be achieved at the system level by joint optimization. We also study conflict and cooperation issues in the supply chain. The cost of conflict of a supply chain partner is a measure of the amount by which the unconstrained optimal cost increases when a decision is to be made under the scheduling constraint imposed by the other partner. We quantify these conflicts and show that the cost of conflicts are significant. We also show that a cooperative decision will generate a positive surplus in the system which can be shared by the two partners to make cooperation and coordination strategy more attractive.  相似文献   
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Summary Similar to the Ziegler's theorem [1] on the influence of nonworking constraints on the stability of elastic systems, a theorem on the influence of elastic supports (constraints), which do perform work during the motion of the system, is derived for conservative elastic systems. The theorem is applicable to both discrete and continuous systems.
Zusammenfassung In Analogie zu einem Satz von Ziegler über den Einfluss arbeitsloser Bindungen auf die Stabilität elastischer Systeme wird ein Theorem über den Einfluss elastischer Einspannungen, die während der Bewegung Arbeit leisten, für konservative Systeme hergeleitet. Es ist sowohl für diskrete als auch für kontinuierliche Systeme anwendbar.
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The first total synthesis of (-)-himgaline and a highly enantioselective synthesis of its congener (-)-GB 13 are described. Decarboxylative aza-Michael reaction of the hexacyclic lactone precursor under acidic conditions, followed by basic workup, yielded (-)-GB 13 in 80% yield. Cyclization of (-)-GB 13 to oxohimgaline under acidic conditions, followed by internally coordinated sodium triacetoxyborohydride reduction, gave (-)-himgaline as the exclusive product.  相似文献   
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We study the performance of scheduling algorithms for a manufacturing system, called the ‘no-wait flowshop’, which consists of a certain number of machine centers. Each center has one or more identical parallel machines. Each job is processed by at most one machine in each center. The problem of finding the minimum finish time schedule is considered here in a flowshop consisting of two machine centers. Heuristic algorithms are presented and are analyzed in the worst case performance context. For the case of two centers, one with a single machine and the other with m, two heuristics are presented with tight performance guarantees of 3 − (1/m) and 2. When both centers have m machines, a heuristic is presented with an upper bound performance guarantee of . It is also shown that this bound can be reduced to 2(1 + ε). For the flowshop with any number of machines in each center, we provide a heuristic algorithm with an upper bound performance guarantee that depends on the relative number of machines in the centers.  相似文献   
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In the Generalized Travelling Salesman Problem (GTSP), the aim is to determine a least cost Hamiltonian circuit or cycle through several clusters of vertices. It is shown that a wide variety of combinatorial optimization problems can be modelled as GTSPs. These problems include location-routeing problems, material flow system design, post-box collection, stochastic vehicle routeing and arc routeing.  相似文献   
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This paper considers design and operational issues that arise in repetitive manufacturing systems served by automated guided vehicles (AGVs) in loop layouts with unidirectional material flow. Such systems are in widespread industrial use, and play an important role in modern manufacturing environments. The objective considered is the minimization of AGV fleet size, given the minimum steady state cycle time required to produce a minimal job set (or equivalently, given the maximum throughput rate). We also study whether the decomposition of a large AGV-served flowshop loop into several smaller loops improves productivity. The original loop and the decomposed design are compared with respect to the minimum cycle time needed for the repetitive manufacture of a minimal job set. When there are three or more machines in the loop, finding the optimal cycle time is an intractable problem. We therefore use the genetic algorithm developed in the companion paper [17], to identify whether the original or the decomposed design is more efficient. Our study suggests that many systems perform more productively as a result of decomposition. Finally, we discuss a joint sequencing issue that arises in decomposed systems with limited buffers between the loops, and analyze the tractability of all the relevant joint sequencing problems.  相似文献   
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