•This paper develops a distinctive method to find all d-minimal paths (d-MPs).•A relationship between the circulation problem and the d-MP problem is established.•The developed method seeks for d-MPs ...by solving feasible circulations.•The developed method outperforms the existing methods in finding all d-MPs.
Multi-state minimal paths, called d-minimal paths (d-MPs), are a popular tool for computing the reliability of multi-state flow networks. Most of the existing algorithms seek for d-MPs by solving an NP-hard Diophantine system in terms of the implicit enumeration method that is simple yet inefficient. This paper focuses on the development of a novel method for finding all d-MPs. By exploring the relationship between d-MPs and feasible circulations that are a well-known network flow problem, this paper proposes a distinctive method integrating the traditional max-flow algorithm and a partition technique to find all d-MPs. The developed method seeks for d-MPs by solving feasible circulations, rather than by solving an NP-hard Diophantine system; additionally, it neither requires MPs nor generates duplicate d-MPs during the solution process. Both theoretical and experimental results demonstrate the advantage of the developed method, and a real delivery network example is presented to illustrate its application.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Excellent performances of various materials often depend on high specific surface areas. Therefore, increase of specific surface areas is one of the most important means to improve the properties and ...performances of materials. Herein, we report a facile strategy to prepare novel composite materials of zeolites and hydrotalcite-like layered double hydroxides, with high specific surface areas. The composites with a rose-like morphology were synthesized hydrothermally by adding synthetic zeolites to the raw materials used for the formation of hydrotalcite. The resultant composites were shown to contain two distinct layered double hydroxides with different Mg/Al molar ratios. Nitrogen (N2) adsorption−desorption measurements showed that the specific surface areas and the pore volumes of these composites increased by an order of magnitude in comparison with hydrotalcite. The new composites were shown to be capable of effectively removing Cr(VI), Cu(II) and methylene blue from aqueous environments and had better performances for the latter two contaminants than hydrotalcite. Moreover, this strategy potentially opens up the synthesis of new composite materials with tunable compositions and enhanced properties for environmental and other applications.
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•A facile strategy to prepare rose-like composite materials has been developed.•The composites composed of zeolites and layered double hydroxides (LDHs).•The synthesized composites have high specific surface area and pore volumes.•The composites can effectively remove Cr(VI), Cu(II) and methylene blue.•This report aims to pursue the synergistic effects of zeolites and LDHs.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•A (d, b)-minimal path method is developed to compute the reliability index R(d,b).•A modified model is constructed to search for (d, b)-minimal paths.•A novel and fast technique is devised to ...identify duplicate (d, b)-MPs.•The developed method indicates distinct advantages over the existing ones.
Reliability and delivery cost are two crucial indicators to show whether a distribution network is in the stable and high-quality operation. This paper develops a (d, b)-minimal path ((d, b)-MP) based algorithm to compute the reliability R(d,b) of a stochastic distribution network as the probability that a prescribed demand d can be successfully delivered from the source to the destination subject to the constraint that the total delivery cost is not above b. Specifically, this paper focuses two aspects to facilitate the solution of (d, b)-MPs. Firstly, by transforming a large Diophantine system into several small Diophantine systems, a modified model is constructed to promote the efficiency of searching for (d, b)-MP candidates and narrow the scope of duplicate (d, b)-MPs. Secondly, a novel technique is devised to identify all duplicate (d, b)-MPs, and its efficiency advantage is theoretically proven. Finally, it is demonstrated through numerical experiments that the developed algorithm compares favorably with the existing ones in the literature, and a case study is provided to display the application of the algorithm.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Reliability evaluation is a useful tool for network performance demonstration, and therefore has become an increasingly relevant task in network design and operation. The multistate minimal cut ...(called d -MC for short) method is a popular algorithm for reliability evaluation of multistate flow networks. This article focuses on d -MC problem, and presents some new results to improve its solution. Grounded on the newly obtained results, an algorithm is proposed to find d -MCs, together with discussions on its time complexity that compares favorably with the existing methods. An illustration of the presented algorithm is provided by solving a simple example. Furthermore, numerical experiments and a case study are conducted to demonstrate the advantage and the utility of the proposed algorithm, respectively.
•Emission is incorporated into reliability analysis of a distribution network.•A new performance indicator is proposed to assess a distribution network.•An MP based algorithm is developed to compute ...the new indicator.•A real case study of a fruit distribution network is presented.
This paper proposes a new reliability assessment for a distribution network with carbon emission constraint where a node represents a supplier, a distribution center, or a market, and an arc connecting a pair of nodes represents a carrier. The available capacity of each carrier (e.g., number of vehicles) is stochastic due to unexpected events. In this sense, such a distribution network is considered to be a stochastic-flow distribution network (SFDN). In addition, transportation emissions that have direct hazardous effects on environment and human health are becoming the major concern in the process of commodity distribution. Thus, SFDN reliability with carbon emission constraint, defined as the probability that the network can successfully deliver a specified quantity of goods from the source to the destination with the total transportation emissions no more than a given limitation, is taken as a key performance indicator for distribution activity. Grounded on minimal paths (MPs), an algorithm is proposed to calculate the new indicator. A simple example is provided to illustrate the procedure, and then, a real fruit distribution network is adopted to demonstrate the utility of the proposed algorithm.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•This paper presents a new search method to find (d,b)-minimal paths ((d, b)-MPs).•A correlation between (d, b)-MP and minimum cost circulation is established.•The presented method searches for d-MPs ...via minimum feasible circulations.•The presented method outperforms the existing ones in finding all (d, b)-MPs.
The reliability and cost integrated performance measure R(d,b) of a multi-state flow network, defined as the probability of sending a flow of d units from the source to the sink with the total transmission cost no more than b, can be computed by means of (d, b)-minimal paths ((d, b)-MPs). The existing methods search for (d, b)-MPs by solving a large Diophantine system or several Diophantine subsystems that are shown to be NP-hard, then the computational efforts are prohibitive. This paper proposes a new search method for (d, b)-MPs, and major contributions include: (1) a correlation between (d, b)-MPs and minimum cost circulations is established, enabling the solution of (d, b)-MPs to be accomplished via minimum cost circulations; (2) a distinctive method merging the well-known capacity scaling algorithm and a decomposition technique is presented to find (d, b)-MPs. In contrast to the existing methods, the presented algorithm seeks for (d, b)-MPs without depending upon the solutions of Diophantine system and generating any duplicate (d, b)-MPs. An illustration of the proposed algorithm is presented, and computational results indicate the advantage of our algorithm over the existing methods.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Scavenger receptors are an important class of pattern recognition receptors that play several important roles in host defense against pathogens. The class C scavenger receptors (SRCs) have only been ...identified in a few invertebrates, and their role in the immune response against viruses is seldom studied. In this study, we firstly identified an SRC from kuruma shrimp, Marsupenaeus japonicus, designated MjSRC, which was significantly upregulated after white spot syndrome virus (WSSV) challenge at the mRNA and protein levels in hemocytes. The quantity of WSSV increased in shrimp after knockdown of MjSRC, compared with the controls. Furthermore, overexpression of MjSRC led to enhanced WSSV elimination via phagocytosis by hemocytes. Pull-down and co-immunoprecipitation assays demonstrated the interaction between MjSRC and the WSSV envelope protein. Electron microscopy observation indicated that the colloidal gold-labeled extracellular domain of MjSRC was located on the outer surface of WSSV. MjSRC formed a trimer and was internalized into the cytoplasm after WSSV challenge, and the internalization was strongly inhibited after knockdown of Mjβ-arrestin2. Further studies found that Mjβ-arrestin2 interacted with the intracellular domain of MjSRC and induced the internalization of WSSV in a clathrin-dependent manner. WSSV were co-localized with lysosomes in hemocytes and the WSSV quantity in shrimp increased after injection of lysosome inhibitor, chloroquine. Collectively, this study demonstrated that MjSRC recognized WSSV via its extracellular domain and invoked hemocyte phagocytosis to restrict WSSV systemic infection. This is the first study to report an SRC as a pattern recognition receptor promoting phagocytosis of a virus.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The Toll pathway is essential for inducing an immune response to defend against bacterial invasion in vertebrates and invertebrates. Although Toll receptors and the transcription factor Dorsal were ...identified in different shrimp, relatively little is known about how the Toll pathway is activated or the function of the pathway in shrimp antibacterial immunity. In this study, three Tolls (Toll1-3) and the Dorsal were identified in
. The Toll pathway can be activated by Gram-positive (G
) and Gram-negative (G
) bacterial infection. Unlike Toll binding to Spätzle in
, shrimp Tolls could directly bind to pathogen-associated molecular patterns from G
and G
bacteria, resulting in Dorsal translocation into nucleus to regulate the expression of different antibacterial peptides (AMPs) in the clearance of infected bacteria. These findings suggest that shrimp Tolls are pattern recognition receptors and the Toll pathway in shrimp is different from the
Toll pathway but identical with the mammalian Toll-like receptor pathway in its activation and antibacterial functions.
Galectins are a lectin family characterized by a conserved sequence motif in the carbohydrate recognition domain, which preferential binds to galactosyl moieties. However, few studies about the ...biological roles of galectins in invertebrates have been reported except for the galectin (CvGal1) from the eastern oyster Crassostrea virginica. Furthermore, galectins have been described in only a few crustacean species, and no functional studies have been reported so far. In this study, we identified and functionally characterized a galectin from the kuruma shrimp Marsupenaeus japonicus, which we designated MjGal. Upon Vibrio anguillarum challenge, expression of MjGal was up-regulated mostly in hemocytes and hepatopancreas, and the protein bound to both Gram-positive and Gram-negative bacteria through the recognition of lipoteichoic acid (LTA) or lipopolysaccharide (LPS), respectively. By also binding to the shrimp hemocyte surface, MjGal functions as an opsonin for microbial pathogens, promoting their phagocytosis. Further, as shown by RNA interference, MjGal participates in clearance of bacteria from circulation, and thereby contributes to the shrimp's immune defense against infectious challenge. Elucidation of functional and mechanistic aspects of shrimp immunity will enable the development of novel strategies for intervention in infectious diseases currently affecting the shrimp farming industry worldwide.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Multistate flow networks (MFNs) and their reliability problem have been studied extensively. However, most of the research on MFN reliability assumes that flow into and out of any arc is equal. In ...practical applications, flow may experience loss during transmission such that flow into and out of an arc may not be equal. Thus, this article concentrates on the reliability of an MFN with flow loss effect, defined as the probability that the sink node can receive a flow of at least d units when the flow experiences loss without replenishment during transmission. Using minimal paths, a simple method is put forth to compute this reliability index, and the solution procedure is illustrated via a simple network example. Finally, computational experiments are provided to investigate the impact of flow loss on network reliability.
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