A branch and cut algorithm for the container shipping network design problem

The network design problem in liner shipping is of increasing importance in a strongly competitive market where potential cost reductions can influence market share and profits significantly. In this paper the network design and fleet assignment problems are combined into a mixed integer linear programming model minimizing the overall cost. To better reflect the real-life situation we take into account the cost of transhipment, a heterogeneous fleet, route dependent capacities, and butterfly routes. To the best of our knowledge it is the first time an exact solution method to the problem considers transhipment cost. The problem is solved with branch-and-cut using clover and transhipment inequalities. Computational results are reported for instances with up to 15 ports.     

A note on liner ship fleet deployment

Liner ship fleet deployment is the assignment of ships to liner service routes for delivering containers in a planning horizon. This paper first reformulates the maximum number of voyages that can be completed in the planning horizon, which is incorrectly defined by the existing studies on liner ship fleet deployment. It proceeds to remedy a constraint in Gelareh and Meng (Transp Res 46E:76?C89 2010) such that the nonlinear programming model proposed by Gelareh and Meng (Transp Res 46E:76?C89 2010) is equivalent to its linear formulation. Finally, a reformulation of the fleet deployment model is presented to eliminate the combinatorial behavior of the model proposed by Gelareh and Meng (Transp Res 46E:76?C89 2010). Computational study demonstrates significant efficiency improvement of the reformulated model.     

Linking environmental conditions and ship movements to estimate invasive species transport across the global shipping network

Aim Some nations, and the International Maritime Organization, are moving towards requirements for managing ballast water to reduce the number of alien species transported and released. These and other measures will be most efficient when targeted at ships posing the greatest risks. Here, we analyse world‐wide ship movements and port environmental conditions to explore how these risk components differ across arriving ships. Location Global, with a case study of the Laurentian Great Lakes. Methods We gathered salinity and temperature data for all global shipping ports, and data for all global ship movements during a 12 ‐month period. We applied these data to the Laurentian Great Lakes to determine which global ports may donate new species to the Great Lakes via ship traffic, and which are most environmentally similar to the Great Lakes. Results We show that ships regularly travel to the Great Lakes from all major coastal, and many inland, regions of the world. Most global ports, and thus the species in them, are separated from the Great Lakes by no more than two ship voyages. Combined with a measure of environmental similarity among global ports, we identify ship routes likely to transport species adapted for survival in the Great Lakes and global regions that may be the source of increasing future invasions. Main conclusions The Great Lakes account for a small fraction of global shipping yet are closely connected to all other ports, and the species in them, by the shipping network. Our methods and data allow risks from individual ships to be ranked so that management activities can be targeted at ships most likely to introduce new invaders. Because our data sets are global, they could be applied to ship arrivals at any global port.     

International dissemination of epidemic Vibrio cholerae by cargo ship ballast and other nonpotable waters.

In 1991 and 1992, toxigenic Vibrio cholerae O1, serotype Inaba, biotype El Tor, was recovered from nonpotable (ballast, bilge, and sewage) water from five cargo ships docked in ports of the U.S. Gulf of Mexico. Four of these ships had taken on ballast water in cholera-infected countries; the fifth took on ballast in a noninfected country. Isolates examined by pulsed-field gel electrophoresis were indistinguishable from the Latin American epidemic strain, C6707; however, they differed significantly from the endemic Gulf Coast strain (VRL 1984), the sixth-pandemic strain (569-B), and a V. cholerae non-O1 strain isolated from a ship arriving from a foreign port. On the basis of our findings, the Food and Drug Administration recommended that the U.S. Coast Guard issue an advisory to shipping agents and captains requesting that ballast waters be exchanged on the high seas before entry of ships into U.S. ports.     

A freight network planning model in oligopolistic shipping markets

The paper presents a multi-level hierarchical approach which models the oligopolistic behavior of carriers in maritime freight transportation networks. With the merger of the carriers’ industry and some dominant carriers in today’s shipping markets, carrier competition frequently exhibits an oligopolistic nature. This study considers the following three types of carriers; ocean carriers, land carriers, and port terminal operators. The oligopolistic ocean carriers, land carriers, and port terminal operators compete with each other in their pricing and routing decisions. The carriers determine service charges and delivery routes at different parts of the multi-modal freight network, creating hierarchical relationships. When using a game theoretic approach, ocean carriers become the leaders in an oligopoly shipping market. When dealing with individual carrier problems, the Nash equilibrium reveals the optimal decision where each carrier obtains the greatest profit. A three-level model is formulated to capture the interactions among different types of carriers. The validity and capability of the model gets demonstrated through an empirical example.     

Ships in Distress,Environmental Threats to Coastal States,and Places of Refuge: New Directions for an Ancien Regime ?

Places of refuge for ships in distress is a topic before the International Maritime Organization as a result of several recent well-publicized refusals by maritime authorities of coastal states to allow such ships to enter sheltered waters within national jurisdiction. The traditional right of refuge of the crew, ship, and cargo is pitted against threat perceptions held by coastal states resulting in a "not in my backyard" syndrome. Instances of modern state practice seem to restrict the right of refuge to a purely humanitarian dimension. There is a need to reevaluate the right of refuge and to establish a system of places of refuge on the basis of regional cooperation to counter the potential threat of stricken ships that are unable to effect necessary repairs in sheltered areas within national jurisdiction.     

Diatom community structure on in-service cruise ship hulls

Diatoms are an important component of marine biofilms found on ship hulls. However, there are only a few published studies that describe the presence and abundance of diatoms on ships, and none that relate to modern ship hull coatings. This study investigated the diatom community structure on two in-service cruise ships with the same cruise cycles, one coated with an antifouling (AF) system (copper self-polishing copolymer) and the other coated with a silicone fouling-release (FR) system. Biofilm samples were collected during dry docking from representative areas of the ship and these provided information on the horizontal and vertical zonation of the hull, and intact and damaged coating and niche areas. Diatoms from the genera Achnanthes, Amphora and Navicula were the most common, regardless of horizontal ship zonation and coating type. Other genera were abundant, but their presence was more dependent on the ship zonation and coating type. Samples collected from damaged areas of the hull coating had a similar community composition to undamaged areas, but with higher diatom abundance. Diatom fouling on the niche areas differed from that of the surrounding ship hull and paralleled previous studies that investigated differences in diatom community structure on static and dynamically exposed coatings; niche areas were similar to static immersion and the hull to dynamic immersion. Additionally, diatom richness was greater on the ship with the FR coating, including the identification of several new genera to the biofouling literature, viz. Lampriscus and Thalassiophysa. These results are the first to describe diatom community composition on in-service ship hulls coated with a FR system. This class of coatings appears to have a larger diatom community compared to copper-based AF systems, with new diatom genera that have the ability to stick to ship hulls and withstand hydrodynamic forces, thus creating the potential for new problematic species in the biofilm.     

Evidence that ship noise increases stress in right whales

Baleen whales (Mysticeti) communicate using low-frequency acoustic signals. These long-wavelength sounds can be detected over hundreds of kilometres, potentially allowing contact over large distances. Low-frequency noise from large ships (20-200 Hz) overlaps acoustic signals used by baleen whales, and increased levels of underwater noise have been documented in areas with high shipping traffic. Reported responses of whales to increased noise include: habitat displacement, behavioural changes and alterations in the intensity, frequency and intervals of calls. However, it has been unclear whether exposure to noise results in physiological responses that may lead to significant consequences for individuals or populations. Here, we show that reduced ship traffic in the Bay of Fundy, Canada, following the events of 11 September 2001, resulted in a 6 dB decrease in underwater noise with a significant reduction below 150 Hz. This noise reduction was associated with decreased baseline levels of stress-related faecal hormone metabolites (glucocorticoids) in North Atlantic right whales (Eubalaena glacialis). This is the first evidence that exposure to low-frequency ship noise may be associated with chronic stress in whales, and has implications for all baleen whales in heavy ship traffic areas, and for recovery of this endangered right whale population.     

The Use of LNG as a Marine Fuel: The International Regulatory Framework

While shipping is a carbon efficient transport mode, given that roughly 90% of the world trade is carried by ships, the negative impact of shipping on human health and the natural environment is significant. One of the attempts being made by the shipping industry to reduce its environmental impact is to use liquefied natural gas (LNG) as a marine fuel. This article examines the regulatory legal regime in relation to the use of LNG as marine fuel and highlights the areas where further development is necessary.     

Evolution, structure and function of mitochondrial carriers: a review with new insights

The mitochondrial carriers (MC) constitute a large family (MCF) of inner membrane transporters displaying different substrate specificities, patterns of gene expression and even non-mitochondrial organelle localization. In Arabidopsis thaliana 58 genes encode these six trans-membrane domain proteins. The number in other sequenced plant genomes varies from 37 to 125, thus being larger than that of Saccharomyces cerevisiae and comparable with that of Homo sapiens. In addition to displaying highly similar secondary structures, the proteins of the MCF can be subdivided into subfamilies on the basis of substrate specificity and the presence of specific symmetry-related amino acid triplets. We assessed the predictive power of these triplets by comparing predictions with experimentally determined data for Arabidopsis MCs, and applied these predictions to the not yet functionally characterized mitochondrial carriers of the grass, Brachypodium distachyon, and the alga, Ostreococcus lucimarinus. We additionally studied evolutionary aspects of the plant MCF by comparing sequence data of the Arabidopsis MCF with those of Saccharomyces cerevisiae and Homo sapiens, then with those of Brachypodium distachyon and Ostreococcus lucimarinus, employing intra- and inter-genome comparisons. Finally, we discussed the importance of the approaches of global gene expression analysis and in vivo characterizations in order to address the relevance of these vital carrier proteins.     

Cryptostylochus hullensis sp. nov. (Polycladida,Acotylea, Platyhelminthes): A possible case of transoceanic dispersal on a ship’s hull

In July 1993, the car carrier “Faust” entered Bremerhaven after a voyage from the North-American Atlantic coast to Europe. In a dockyard, five living specimens of the order Polycladida were collected from the hull of the ship. This could be a possible case of trans-atlantic dispersal of plathelminths living as fouling organisms of ships. The specimens found represent a new species of the genusCryptostylochus Faubel, 1983,Cryptostylochus hullensis sp. nov.     

Nature: a vital source of leads for anticancer drug development

Over 60% of the current anticancer drugs have their origin in one way or another from natural sources. Nature continues to be the most prolific source of biologically active and diverse chemotypes, and it is becoming increasingly evident that associated microbes may often be the source of biologically active compounds originally isolated from host macro-organisms. While relatively few of the actual isolated compounds advance to become clinically effective drugs in their own right, these unique molecules may serve as models for the preparation of more efficacious analogs using chemical methodology such as total or combinatorial (parallel) synthesis, or manipulation of biosynthetic pathways. In addition, conjugation of toxic natural molecules to monoclonal antibodies or polymeric carriers specifically targeted to epitopes on tumors of interest can lead to the development of efficacious targeted therapies. The essential role played by natural products in the discovery and development of effective anticancer agents, and the importance of multidisciplinary collaboration in the generation and optimization of novel molecular leads from natural product sources is reviewed.     

Augmentation of Host Resistance against Bacterial Infection by Treatment with Leustroducsin B,a New CSF Inducer

We tested the in vivo activity of leustroducsin B (LSN B), a new colony-stimulating factor (CSF) inducer isolated from the culture broth of Streptomyces platensis, with mice infected with Escherichia coli. Treatment with LSN B augmented the host resistance to lethal infection of E. coli at doses between 0.1 mg/kg and 1 mg/kg. Serum interleukin-6 (IL-6) levels were found to increase after this treatment, and superoxide anion generation of neutrophils was enhanced in vivo, suggesting that LSN B augmented the host resistance at least in part by inducing IL-6, which subsequently enhanced the bactericidal activity of the neutrophils.     

Ship Breaking and the Steel Industry in Bangladesh: A Material Flow Perspective

Bangladesh has emerged as a leading ship breaking nation. We conducted a material flow analysis of steel in Bangladesh with an emphasis on the ship breaking industry (SBI). The total aggregate domestic steel consumption in fiscal year (FY) 2010 was 2,930,000 tonnes (t) in Bangladesh; SBI met approximately 51% of the demand for raw materials and 37% of the demand for finished steel products. Rolling industries output in FY2010 was 1,451,000 t; 23% of the input for this production was from ship breaking sources. Dismantled ships also generate high‐quality reusable steel scraps. SBI was found to be the sole source of scraps for small rerolling industries in Bangladesh, and their output in 2008 more than doubled as compared to 2005. Larger rolling industries fulfilled their input needs for steel scraps by using both SBI and imported materials. We found a sharp increase in input imports during the global ship breaking recession in 2003–2007 and when Bangladesh's SBI faced a temporary ban in 2010. Induction furnaces in Bangladesh in FY2010 produced a total of 787,000 t of billets; more than 40% was from ship‐sourced scraps. In 2008, the country's steel consumption was 3,220,000 t, that is, 22 kilograms per person, and the intensity of steel use was 40 grams per U.S. dollar, which was much higher than that of other developing countries with a similar per capita gross domestic product (GDP). The country exhibited a high level of steel consumption relative to its GDP, which is indicative of the contribution of SBI.     

Vectored introductions of marine endosymbiotic dinoflagellates into Hawaii

Endosymbiotic dinoflagellates belonging to the genus Symbiodinium associate with a diverse range of marine invertebrate hosts and also exist free-living in the ocean. The genus is divided into eight lineages (clades A–H), which contain multiple subclade types that show geographic and host specificity. It is commonly known that free-living dinoflagellates can and have been introduced to new geographic locations, primarily through shipping ballast water. In this study we sequenced the ITS2 region of Symbiodinium found in symbiosis with the coral Acropora cytherea in the Northwestern Hawaiian Islands Marine National Monument and from shipping ballast water. Identification of an unusual symbiont in Acropora cytherea and an analysis of the distribution of this symbiont suggests an introduction to Hawaii vectored by the scyphozoan host, Cassiopea sp. Symbiodinium were also detected in shipping ballast water. This work confirms that marine invertebrate endosymbionts can be introduced to new geographic locations vectored by animal hosts or the ballast water of ships.     

The role of containerships as transfer mechanisms of marine biofouling species

Fouling of ships is an important historical and enduring transfer mechanism of marine nonindigenous species (NIS). Although containerships have risen to the forefront of global maritime shipping since the 1950s, few studies have directly sampled fouling communities on their submerged surfaces, and little is known about differences in the fouling characteristics among commercial ship types. Twenty-two in-service containerships at the Port of Oakland (San Francisco Bay, California) were sampled to test the hypothesis that the extent and taxonomic richness of fouling would be low on this type of ship, resulting from relatively fast speeds and short port durations. The data showed that the extent of macroorganisms (invertebrates and algae) was indeed low, especially across the large surface areas of the hull. Less than 1% of the exposed hull was colonized for all apart from one vessel. These ships had submerged surface areas of >7000 m², and fouling coverage on this area was estimated to be <l7 m² per vessel, with zero biota detected on the hulls of many vessels. The outlying smaller vessel (4465 m²) had an estimated coverage of 90% on the hull and also differed substantially from the other ships in terms of its recent voyage history, shorter voyage range and slower speeds. Despite the low extent of fouling, taxonomic richness was high among vessels. Consistent with recent studies, a wide range of organisms were concentrated at more protected and heterogeneous (non-hull) niche areas, including rudders, stern tubes and intake gratings. Green algae and barnacles were most frequently sampled among vessels, but hydroids, bryozoans, bivalves and ascidians were also recorded. One vessel had 20 different species in its fouling assemblage, including non-native species (already established in San Francisco Bay) and mobile species that were not detected in visual surveys. In contrast to other studies, dry dock block areas did not support many organisms, despite little antifouling deterrence in some cases. Comparisons with previous studies suggest that the accumulation of fouling on containerships may be lower than on other ship types (eg bulkers and general cargo vessels), but more data are needed to determine the hierarchy of factors contributing to differences in the extent of macrofouling and non-native species vector risks within the commercial fleet.     

The effect of destruction and stimulation of the lateral nucleus of the septum pellucidum on the structure and functions of the ovaries and the mechanism of such influences]

The experiments on the immature female rats were carried out to show the effects of damage or stimulation of the lateral septal nucleus (LSN) on the ovary function and its response to chorionic gonadotrophin. The damage of the LSN decreases the ovary weight, but enlarges mature ovarian follicles and increases the estrogen production. LSN lesions in hypophysectomized rats have no effect on the ovary and uterus weights as compared to hypophysectomized ones, but decrease the size of mature ovarian follicles against a background of hypophysectomy or LSN lesions. Damage of the LSN increases ovary and uterus sensitivity to the chorionic gonadotrophin injections. A conclusion is drawn on the existence of parahypophysial way to transfer the influence of LSN on the rat ovaries. The possible mechanisms of LSN influence on the reproduction system of female rats is under discussion.     

Optimization of immobilization conditions for vinegar production. Siran,wood chips and polyurethane foam as carriers for Acetobacter aceti

A complete experimental design has been developed to study the properties of three different solid carriers (Siran, wood chips and polyurethane foam) in the immobilization of acetic acid bacteria. Temperature-controlled reactors of 450-ml volume were employed to compare a standard immobilization procedure consisting of consecutive discontinuous acetic acid fermentations in the presence of the carrier. On reaching the final saturation condition, the different immobilized carriers were removed and introduced into identical sterilized reactors. These were then submitted to several semi-continuous fermentation cycles with the aim of characterising and comparing their acetification properties. Immobilization and acetification data obtained in this study have been evaluated in order to determine the best carrier material on the basis of several technical criteria. Polyurethane foam was the most successful because it allows a huge number of immobilized cells in the shortest time and leads to the highest acetification rate of the three assayed carriers.     

Linkage studies in carriers of Lowe oculo-cerebro-renal syndrome.

A black family with two male infants affected with the X-linked Lowe syndrome was studied. All three females in the pedigree were found to be carriers on the basis of lenticular opacities. Each female had one son. Of these, two were affected and one was unaffected. The Xg blood-group locus and the G6PD locus were determined in these six individuals. Two of the carrier females were heterozygous for G6PD isoenzymes A- and B. Skewing of the A-:B ratio in isolated erythrocytes, lymphocytes, granulocytes, platelets, and cultured skin fibroblasts from these females may be the result of either selection against cells expressing the Lowe gene product or random X-chromosome inactivation. At least one instance of recombination was found between the G6PD and the Lowe syndrome loci. At least two instances of recombination between Xg blood-group and Lowe syndrome loci.