Bi-level optimization programming for the shipper-carrier network problem

The paper presents a bi-level modeling approach that captures hierarchical relationships between shippers and carriers in maritime freight transportation networks. Ocean carriers, land carriers and port terminal operators provide transportation services at different parts of the multimodal network. Port terminal operators are regarded as a special type of carrier due to their behavior. The carriers determine service charges and delivery routes (port services) through competition and interactions among themselves. Shippers are users of the transportation services. Shippers choose a sequence of carriers, based on the carriers’ pricing and routing decisions. These relationships are captured in a bi-level model where carriers are the leaders and shippers are the followers. The paper focuses on the behavior of shippers having the transportation service information with spatial price equilibrium. A numerical example is used to demonstrate the validity of the developed model.     

Cooperative liner shipping network design by means of a combinatorial auction

Cooperation in the ocean liner shipping industry has always been important to improve liner shipping networks (LSN’s). As tight cooperations like alliances are challenged by antitrust laws, looser forms of cooperation among liner carriers might become a reasonable way to increase efficiency of LSN’s. Our goal is to facilitate a loose form of cooperation among liner carriers. Therefore, we introduce a coordination mechanism for designing a collaborative LSN based on a multi round combinatorial auction. Via the auction, carriers exchange demand triplets, i.e. orders which describe the transport of containers between ports. A standard network design problem which includes ship scheduling and cargo routing decisions is used as isolated network design problem of an individual carrier. A carrier has to solve this isolated problem repeatedly during the auction so that the carrier is able to decide which demand triplets to sell, on which demand triplets to bid, and what prices to charge. To solve these problems we propose a variable neighborhood search based matheuristic. The matheuristic addresses the isolated planning problem in four phases (construct ship cycles, modify cycles, determine container flow, and reallocate ships to cycles). Our computational experiments on a set of 56 synthetic test instances suggest that the introduced combinatorial auction increases profits on average compared to isolated planning significantly by 4%. The more diverse the original assignment of demand triplets and ships to carriers is, the higher the potential for collaboration; for 18 diverse instances, the profits increase on average by 10%.     

Kinship on the waterfront: logistics labour in a global port

This article examines how kinship forms a contested element of labour under capitalist distribution. The focus of the article is on a thriving Spanish container port where the dockworker collective has been steadily growing since the multinational companies first arrived in the 1970s. In the wake of containerization – a standardized system of freight transport based on the intermodal shipping container – dock work has been revalued and become attractive in an area otherwise characterized by high unemployment rates and below-average salaries. Drawing on ethnographic research, the article analyses how unionized dockworkers are met with stigmatization from the general public and criticized for their intergenerational access to ‘container capital’. The article contributes to current anthropological debates around the role of labour under global capitalism by tracing the links between kinship and labour in the making of a global port.     

Multi-hop driver-parcel matching problem with time windows

Crowdsourced shipping can result in significant economic and social benefits. For a shipping company, it has a potential cost advantage and creates opportunities for faster deliveries. For the society, it can provide desirable results by reducing congestion and air pollution. Despite the great potential, crowdsourced shipping is not well studied. With the aim of using the spare capacities along the existing transportation flows of the crowd to deliver small-to-medium freight volumes, this paper defines the multi-driver multi-parcel matching problem and proposes a general ILP formulation, which incorporates drivers’ maximum detour, capacity limits, and the option of transferring parcels between drivers. Due to the high computational complexity, we develop two heuristics to solve the problem. The numerical study shows that crowdsourced shipping can be an economic viable and sustainable option, depending on the spatial characteristics of the network and drivers’ schedules. Furthermore, the added benefits increase with an increasing number of participating drivers and parcels.     

桔小实蝇传入风险的模糊综合评估

根据国际有害生物风险评估方案,本文提出了桔小实蝇Bactrocera dorsalis （Hendel）随进口水果传入风险评估的参数指标体系,包括一级评估指标5个： 进口水果种类,进口水果数量,进口水果的虫害率,运输途中害虫存活率,检疫管理的有效性; 二级评估指标9个： 原产地桔小实蝇的防治情况,水果装运前的处理情况,桔小实蝇对水果的嗜好性,水果运输期,运输条件,运输途中极端限制因子的出现情况,检疫抽样百分比,检出率,检疫措施的处理效果等。采用权重分析法确定各个指标的权重,在此基础上,应用模糊决策的基本理论和方法,建立桔小实蝇传入风险的模糊综合评估模型。模拟评估结果认为,进口水果装运前的杀虫处理和水果到岸时的检疫处理对风险值的影响很大,进口水果的数量以及运输途中是否出现极端限制因子也对风险值有明显影响。     

Evaluation of carriers used in the test methods of the Association of Official Analytical Chemists.

Revision of the official test method for the determination of the tuberculocidal activity of disinfectants is being undertaken. The current procedure lacks precision and accuracy and is not quantitative. Variability associated with carriers and the lack of temperature control were evaluated in this paper. The use of porcelain versus stainless steel carriers was also evaluated. When carriers of either type were contaminated with Mycobacterium bovis BCG, the number of organisms on the carriers varied by as much as 1.0 on the log10 scale. The average number of organisms attached to each porcelain carried was 1.10 x 10(5) CFU (range, 2.7 x 10(4) to 2.7 x 10(5) CFU), whereas the average number of organisms attached to each stainless steel carrier was 1.38 x 10(5) CFU (range, 2.9 x 10(4) to 4.0 x 10(5) CFU). The average number of cells attached to the carrier was directly proportional to the number of cells in the contaminating cell suspension. Variations in drying time did not alter the number of cells attached to the carrier. When porcelain carriers were placed in a test solution, the average number of organisms washed from the carriers was 55% of the total, with a range of 19 to 80%, whereas for stainless steel carriers, the average number was 82% of the total, with a range of 52 to 96%. Data for B. subtilis spores were similar to those for M. bovis BCG, suggesting that there may be similar problems with the Association of Official Analytical Chemists sporicidal test, which uses carriers. It was also found that the lack of an exacting temperature control could influence the outcome of the test. Changes in temperature as little as 1 degree C could influence the rate of killing of M. bovis BCG.     

Evaluation of carriers used in the test methods of the Association of Official Analytical Chemists

Revision of the official test method for the determination of the tuberculocidal activity of disinfectants is being undertaken. The current procedure lacks precision and accuracy and is not quantitative. Variability associated with carriers and the lack of temperature control were evaluated in this paper. The use of porcelain versus stainless steel carriers was also evaluated. When carriers of either type were contaminated with Mycobacterium bovis BCG, the number of organisms on the carriers varied by as much as 1.0 on the log10 scale. The average number of organisms attached to each porcelain carried was 1.10 x 10(5) CFU (range, 2.7 x 10(4) to 2.7 x 10(5) CFU), whereas the average number of organisms attached to each stainless steel carrier was 1.38 x 10(5) CFU (range, 2.9 x 10(4) to 4.0 x 10(5) CFU). The average number of cells attached to the carrier was directly proportional to the number of cells in the contaminating cell suspension. Variations in drying time did not alter the number of cells attached to the carrier. When porcelain carriers were placed in a test solution, the average number of organisms washed from the carriers was 55% of the total, with a range of 19 to 80%, whereas for stainless steel carriers, the average number was 82% of the total, with a range of 52 to 96%. Data for B. subtilis spores were similar to those for M. bovis BCG, suggesting that there may be similar problems with the Association of Official Analytical Chemists sporicidal test, which uses carriers. It was also found that the lack of an exacting temperature control could influence the outcome of the test. Changes in temperature as little as 1 degree C could influence the rate of killing of M. bovis BCG.     

Targeted gene delivery: the role of peptide nucleic acid

Receptor-mediated endocytosis can be exploited to achieve efficient cell-specific gene delivery. Our laboratory has used two approaches for targeted gene delivery. One uses polycation as a carrier for plasmid DNA and the other uses peptide nucleic acid (PNA) as a carrier. Targeted gene delivery using polycation carriers has been widely utilized with some success. This approach mainly suffers from large particle size and non-specific interaction with blood components. These drawbacks have limited use of this type of vector forin vivo applications. Using PNA as a carrier, on the other hand, allows for smaller particle size and less non-specific interactions. The stability of this vector in the circulation may be a limiting factor. In addition, both types of vector lack mechanisms for endosome escape and nuclear transport. In this chapter, current developments and uses for targeted gene delivery of each approach are reviewed.     

Generalized plasma skimming model for cells and drug carriers in the microvasculature

In microvascular transport, where both blood and drug carriers are involved, plasma skimming has a key role on changing hematocrit level and drug carrier concentration in capillary beds after continuous vessel bifurcation in the microvasculature. While there have been numerous studies on modeling the plasma skimming of blood, previous works lacked in consideration of its interaction with drug carriers. In this paper, a generalized plasma skimming model is suggested to predict the redistributions of both the cells and drug carriers at each bifurcation. In order to examine its applicability, this new model was applied on a single bifurcation system to predict the redistribution of red blood cells and drug carriers. Furthermore, this model was tested at microvascular network level under different plasma skimming conditions for predicting the concentration of drug carriers. Based on these results, the applicability of this generalized plasma skimming model is fully discussed and future works along with the model’s limitations are summarized.     

Targeted gene delivery: The role of peptide nucleic acid

Receptor-mediated endocytosis can be exploited to achieve efficient cell-specific gene delivery. Our laboratory has used two approaches for targeted gene delivery. One uses polycation as a carrier for plasmid DNA and the other uses peptide nucleic acid (PNA) as a carrier. Targeted gene delivery using polycation carriers has been widely utilized with some success. This approach mainly suffers from large particle size and non-specific interaction with blood components. These drawbacks have limited use of this type of vector for in vivo applications. Using PNA as a carrier, on the other hand, allows for smaller particle size and less non-specific interactions. The stability of this vector in the circulation may be a limiting factor. In addition, both types of vector lack mechanisms for endosome escape and nuclear transport. In this chapter, current developments and uses for targeted gene delivery of each approach are reviewed.     

Targeted gene delivery: the role of peptide nucleic acid

Receptor-mediated endocytosis can be exploited to achieve efficient cell-specific gene delivery. Our laboratory has used two approaches for targeted gene delivery. One uses polycation as a carrier for plasmid DNA and the other uses peptide nucleic acid (PNA) as a carrier. Targeted gene delivery using polycation carriers has been widely utilized with some success. This approach mainly suffers from large particle size and non-specific interaction with blood components. These drawbacks have limited use of this type of vector for in vivoapplications. Using PNA as a carrier, on the other hand, allows for smaller particle size and less non-specific interactions. The stability of this vector in the circulation may be a limiting factor. In addition, both types of vectorlack mechanisms for endosome escape and nuclear transport. In this chapter, current developments and uses for targeted gene delivery of each approach are reviewed.     

Railway capacity and expansion analysis using time discretized paths

When making investments in railway infrastructure it is important to be able to identify the limits for freight transportation in order to not only use the infrastructure in the best possible way, but to also guide future capacity investments. This paper presents a model to assess the capacity of railway freight transportation on a long term strategic level. The model uses an hourly time discretization and analyses the impact of railway network expansions based on future demand forecasts. It provides an optimal macroscopic freight train schedule and can indicate the time and place of any congestion. In addition, two expansions of the primary model are developed. The first can be used to determine the minimal number of expansions needed to ensure all freight can be feasibly routed, while the second can be used to schedule freight trains at hours not congested by passenger trains using variable penalties for the different passenger busy time slots. As part of a European Union project, all models are applied to a realistic case study that focuses on analyzing the capacity of railway network, in Denmark and Southern Sweden using demand forecasts for 2030. Results suggest that informative solutions can be found quickly with the proposed approach.     

Aligning barge and terminal operations using service-time profiles

We consider a key issue in hinterland container navigation in ports, such as Rotterdam and Antwerp, namely the barge handling problem: how to optimize the alignment of barge and terminal operations in a port. We make a major step in solving the barge handling problem for practical settings. Specifically, we consider restricted opening times of terminals, unbalanced networks, the presence of sea vessels, and closing times of containers. Consequently, at a terminal a barge faces time dependency in: (1) the waiting time until the start of handling and (2) the handling time itself. The concept of waiting profiles which we introduced in an earlier paper only deals with (1). To deal with (1) and (2) together we introduce a more comprehensive concept, namely that of service-time profile. To establish how well our approach works, we evaluate the performance of our distributed planning approach extensively by means of simulation. We compare our results with those based on centralized planning by using an off-line benchmark resembling it. We show that the Multi-Agent system that we introduce enables barge and terminal operators to align their operations efficiently. Hence, it can be seen as a promising solution approach for solving the barge handling problem, since it enables (competing) companies to collaborate in a competitive way.     

Coiled coil peptides as universal linkers for the attachment of recombinant proteins to polymer therapeutics

We have designed, synthesized, and characterized peptides containing four repeats of the sequences VAALEKE (peptide E) or VAALKEK (peptide K). While the peptides alone adopt in aqueous solutions a random coil conformation, their equimolar mixture forms heterodimeric coiled coils as confirmed by CD spectroscopy. 5-Azidopentanoic acid was connected to the N-terminus of peptide E via a short poly(ethylene glycol) spacer. The terminal azide group enabled conjugation of the peptide with a synthetic drug carrier based on the N-(2-hydroxypropyl)methacrylamide copolymer containing propargyl groups using "click" chemistry. When incorporated into the polymer drug carrier, peptide E formed a stable noncovalent complex with peptide K belonging to a recombinant single-chain fragment (scFv) of the M75 antibody. The complex thereby mediates a noncovalent linkage between the polymer drug carrier and the protein. The recombinant scFv antibody fragment was selected as a targeting ligand against carbonic anhydrase IX-a marker overexpressed by tumor cells of various human carcinomas. The antigen binding affinity of the polymer-scFv complex was confirmed by ELISA. This approach offers a well-defined, specific, and nondestructive universal method for the preparation of protein (antibody)-targeted polymer drug and gene carriers designed for cell-specific delivery.     

Equilibrium models in multimodal container transport systems

Optimizing the performance of multimodal freight transport networks involves adequately balancing the interplay between costs, volumes, times of departure and arrival, and times of travel. In order to study this interplay, we propose an assignment model that is able to efficiently determine flows and costs in a multimodal network. The model is based on a so-called user equilibrium principle, which is at the basis of Dynamic Traffic Assignment problems. This principle takes into account transport demands to be shipped using vehicles that transport single freight units (such as trucks) or multiple freight units (such as trains and barges, where demand should be bundled to reach efficient operations). Given a particular demand, the proposed model provides an assignment of the demand over the available modes of transport. The outcome of the model, i.e., the equilibrium point, minimizes users’ generalized costs, expressed as a function of mode, travel time and related congestion, and waiting time for bundling sufficient demand in order to fill a vehicle. The model deals with these issues across a doubly-dynamic time scale and in an integrated manner. One dynamic involves a learning dynamic converging towards an equilibrium (day-to-day) situation, reflecting the reaction of the players towards the action of the others. Another dynamic considers the possible departure time that results in minimum expected costs, also due to the fact that players mutually influence each other on the choice of departure times, due to congestion effects and costs for early/late arrival of freight units. This is a choice within a given time horizon such as a day or a week. We present a study on the influence and sensitivity of different model parameters, in order to analyse the implications on strategic decisions, fostering a target modal share for freight transportation. We also study under which conditions the different modes can be substitutes for each other.     

Corridor network design in hinterland transportation systems

In this paper the design of the service network in intermodal barge transport is studied. The network of inland barge terminals is modelled to demonstrate potential cooperations in a corridor network. Cooperation between inland terminals leads to bundling of freight flows in the hinterland of major ports. A service network design model for intermodal barge transport is developed and applied to the hinterland network of the port of Antwerp in Belgium. Selected cooperation schemes are simulated by means of a discrete event simulation model for intermodal barge transport and compared with simulation results of bundling in the port area. Cooperation between inland terminals offers an opportunity to attain economies of scale, but may not be perceived as a sole solution for reducing waiting times of inland barges at sea terminals. A combination of bundling measures in the port area and in the hinterland may be necessary to improve the intermodal transport chain.     

Strategic allocation of cyclically calling vessels for multi-terminal container operators

We consider a terminal operator who provides container handling services at multiple terminals within the same port. In this setting, the well-known berth allocation problem can no longer be considered for each terminal in isolation since vessel calls should be spread over the various terminals to avoid peaks and troughs in quay crane utilization, and an allocation of two connecting vessels to different terminals will generate inter-terminal container transport. In this paper, we address the problem of spreading a set of cyclically calling vessels over the various terminals and allocating a berthing and departure time to each of them. The objectives are (1) to balance the quay crane workload over the terminals and over time and (2) to minimize the amount of inter-terminal container transport. We develop a solution approach based on mixed-integer programming that allows to solve real-life instances of the problem within satisfactory time. Additionally, a practical case study is presented based on data from the terminal operator PSA Antwerp who operates multiple terminals in the port of Antwerp, Belgium. The computational results show the cost of the currently agreed schedules, and that relatively small modifications can significantly reduce the required crane capacities and inter-terminal transport.     

Canine X-linked muscular dystrophy in Japan (CXMDJ).

The purpose of this study was to develop a strain of canine X-linked muscular dystrophy (CXMD), a model of Duchenne muscular dystrophy, in Japan. A female beagle was artificially inseminated with frozen-thawed spermatozoa derived from an affected golden retriever. Subsequently, two carrier female dogs (G1 carriers) and four normal male littermates were produced. Thereafter, the two G1 carriers were mated with beagle sires. As a result, each bitch whelped three times, and out of 54 pups, 17 affected male descendants, and 11 carrier female descendants (G2 carriers) were detected. One G2 carrier was then mated with a beagle sire and 15 pups in two whelpings were produced, including five affected males and four carrier females (G3 carriers). A total of 10 female beagles were artificially inseminated to evaluate the fertility of the frozen-thawed spermatozoa from the two affected dogs. The whelping rates of the two affected dogs were 4/5 and the litter sizes were 5.0 +/- 1.41 and 6.0 +/- 0.82, respectively. These results indicate that a canine X-linked muscular dystrophy colony has been established in Japan. We called them CXMDJ.     

A simple range expansion model of multiple pathways: the case of nonindigenous green crab <Emphasis Type="Italic">Carcinus aestuarii</Emphasis> in Japanese waters

Forecasting the range expansion of nonindigenous organisms enables effective quarantine and the development of pre-arrival countermeasures, as well as raises public and scientific concerns among the general public. Here, we present an approach to forecasting the range expansion of the nonindigenous green crab Carcinus in Japanese waters, with consideration of the human-mediated shipping and natural dispersal. Two types of shipping, namely, primary transport to Japan via long-distance ocean-going shipping and secondary transport within Japan via short-distance coastal shipping, were considered. The presence and absence of the crab in 50-km shoreline segments were obtained at 5 year intervals from 1985 to 2005, based on observation records by professional and amateur naturalists. Two types of dispersal kernel, namely, conventional logistic regression and a multiplicative immigration model considering multiple pathways explicitly, were compared. The multiplicative immigration model gave significantly better results. Natural dispersal was the most significant factor, in spite of its low expansion rate: secondary transport by coastal shipping was the second. Transport by international ocean-going shipping was not statistically significant, suggesting quite a small immigration probability of the crab by long voyages. Stochastic simulations forecasted that the crab will invade most of the coasts of western Japan along the Pacific Ocean and Seto Inland Sea by 2055, and will become widespread all over the country by 2205. Quarantine scenarios to eliminate transport by vessels revealed that preventing crab transport by domestic coastal vessels may delay the arrival of crabs in Hokkaido and the northern Japan area by 700 years at maximum.     

Mitochondrial ATP synthasome. Cristae-enriched membranes and a multiwell detergent screening assay yield dispersed single complexes containing the ATP synthase and carriers for Pi and ADP/ATP

The terminal step of ATP synthesis in intact mitochondria is catalyzed by the ATP synthase (F(0)F(1)) that works in close synchrony with the P(i) and ADP/ATP carriers. Each carrier consists of only a single polypeptide chain in dimeric form, while the ATP synthase is highly complex consisting in animals of 17 known subunit types and more than 30 total subunits. Although structures at high resolution have been obtained for the water-soluble F(1) part of the ATP synthase consisting of only five subunit types, such structures have not been obtained for either the complete ATP synthase or the P(i) and ADP/ATP carriers. Here, we report that all three proteins are localized in highly purified cristae-like vesicles obtained by extensive subfractionation of the mitochondrial inner membrane. Moreover, using a multiwell detergent screening assay, 4 nonionic detergents out of 80 tested were found to disperse these cristae-like vesicles into single soluble complexes or "ATP synthasomes" that contain the ATP synthase in association with the P(i) and ADP/ATP carriers. These studies offer new mechanistic insights into the terminal steps of oxidative phosphorylation in mitochondria and set the stage for future structural efforts designed to visualize in atomic detail the entire complex involved. They also provide evidence that the cristae are a subcompartment of the inner membrane.