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In the slab warehouses of iron and steel enterprises, the slabs are stacked on top of others. Thus, some slabs will be blocked by others from being retrieved directly. In this study, we focus on optimising slab storage and pre-marshalling moves in advance so as to minimise the numbers of slabs which may block retrieval slab, the number of stacks occupied by slabs, and the number of required moves. We also address the practical concern of moving no more than two slabs together. To solve this problem, we present an integer linear programming model and further propose valid inequalities to enhance the model. Based on the labelled data from this modelling approach, a self-training technique is applied to train two functions which can predict the optimal following pre-marshalling move and storage move. By combining these functions, heuristics and branch-and-bound algorithm with the dominance rules, a multi-stage hybrid algorithm is proposed to solve practical problems. The experimental results show the effectiveness of the model, the valid inequalities, and the different components of hybrid algorithm which can produce high-quality solutions within seconds. [ABSTRACT FROM AUTHOR]

Consolidation plan (CP) and stowage plan (SP) of coil ships are to assign steel coils onto ships and decide specific loading location for each coil, respectively, which are two correlative and adjacent plans in the finished product logistics of iron and steel industry. In this paper, we focus on the problem of making an integrated plan of CP and SP (C&SPP), which is important and rarely studied, to try to achieve systematic optimisation from the perspectives of the product terminal, shipping companies, and customers, simultaneously. First, according to the practical situation, an integer programming (IP) model is established to optimise ship loading, transportation timeliness, and operation efficiency. Then, to improve calculating efficiency, the IP model is simplified (SIP) by reducing the dimensions of variables. After that, based on the problem features and algorithm behaviour, an improved differential evolution algorithm is proposed in which an element-dependent strategy is designed to set control parameter, a guided operator is constructed to generate mutant individual and an iteration-based mechanism is introduced to dynamically adjust the parameter and mutation strategy, respectively. Finally, extensive experiments are carried out to evaluate the proposed method, and the numerical results demonstrate its effectiveness in solving practical scale C&SPP. [ABSTRACT FROM AUTHOR]

We study the slab pre-marshalling problem to re-position slabs in a way that the slabs are stored in the least number of stacks and each stack contains only the slabs of the same group, which can be utilised interchangeably. In this way, when a slab of any group is required, the topmost slab can always be picked up without shuffling. During pre-marshalling, however, at most two slabs can be moved by one operation. In this paper, we present a network model with three valid inequalities to solve this problem. With a small amount of labelled data from the model approach, a self-training technique is applied to train a function for predicting the best next move. Then, a new hybrid algorithm is developed to solve the practical problems by combining the self-training technique, heuristics, and the branch-and-bound algorithm with five dominance rules. The experimental results demonstrate the effectiveness of this network model and valid inequalities, and the performances of different components of this algorithm. The new algorithm produces high-quality solutions within seconds. [ABSTRACT FROM AUTHOR]

As an important optimisation problem in the finished product terminal of an iron and steel enterprise, the steel coil ship stowage-planning problem is to determine the stowing locations for the planned coils on a ship. Although the problem has attracted attention, the research has focused only on the optimisation for the ship. In this study, the problem is investigated from the view of improving operation efficiency of the cranes on the quay and in the warehouse. For this purpose, an integer-programming model is established to minimise the coil dispersion on the ship and the moving distance of the warehouse cranes by determining the stowing locations and loading sequence of the coils. To improve the solution efficiency, a two-level hybrid differential evolution (TLDE) composed of a continuous DE and a discrete DE is designed to assign the coils to the rows on the ship, and then allocate locations for them. Further, a subpopulation-based local search and a human experience-based heuristic are developed to further adjust the coils within each row and to produce initial population for TLDE, respectively. Extensive comparison experiments are performed to demonstrate the proposed algorithm. Numerical results confirm that TLDE is an efficient method for solving the SSPP. [ABSTRACT FROM AUTHOR]

Train stowage planning problem of steel coil (TSPP) is to determine loading locations of the coils on train railcars, which is rarely studied, and an important optimisation problem in real iron and steel industry. In this paper, first, according to the actual situations of a steel products transportation department, the problem is formulated as an integer programming (IP) mathematical model in which multiple destination stations, varied stowing modes and different railcar types are considered. Then, on the basis of a general discrete optimisation algorithm framework, i.e. pointer-based discrete differential evolution (PDDE), a novel variant (T-PDDE) is proposed for effectively solving the TSPP. In particular, to deal with the issue of transformation between stowage plan and algorithm individual, a problem-based coding method is designed. To further enhance the algorithm performance, a double levels evolution strategy and an opposite-based local search are developed based on the features of problem. Finally, with the practical and simulative data, extensive comparison experiments are carried out to evaluate the proposed algorithm. The numerical results demonstrate the superiority of T-PDDE on solving TSPP. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study is to compare the short-term and pathological outcomes of TPLRC (Three-port laparoscopic right hemicolectomy) and FPLRC (Five-port laparoscopic right hemicolectomy), using propensity score matching analysis. Methods: One hundred and sixty-eight patients who accepted laparoscopic right hemicolectomy with either three ports or five ports from January 2013 to October 2017 were non-randomly selected and analyzed retrospectively. Propensity score matching model was used to eliminate the patients' selection bias between two groups. Results: A total of 168 patients were involved. After propensity score matching, 39 for each group were compared. The number of harvested lymph nodes was significantly larger in the TPLRC group than in the FPLRC group (18.36 ± 8.58 vs. 14.90 ± 6.63, p = 0.048). A lower mean operative time was observed in the TPLRC group (136.24 ± 26.78 vs. 168.64 ± 43.68 min, p < 0.001). A less blood loss in the TPLRC group (62.44 ± 55.17, 135.54 ± 139.11 ml, p = 0.003). No significant differences in the other short-term outcomes between the two groups. Conclusions: TPLRC is a safe and feasible surgical procedure with similar results of FPLRC in short-term clinical outcomes. TPLRC has the advantages of shorter operative time, less blood loss and larger number of harvested lymph nodes. A randomized prospective clinical trial of long-term outcomes of TPLRC is required to further prove the present results. [ABSTRACT FROM AUTHOR]

Objectives: Colorectal cancer (CRC), one of the most aggressive gastrointestinal malignancies, is a frequently diagnosed life-threatening cancer worldwide. Most CRC patients have poor prognosis mainly because of frequent metastasis and recurrence. Thus, it is crucial to find out some new biomarkers and to show deeper insights into the mechanisms of CRC. MLLT10, Myeloid/lymphoid or mixed-lineage leukemia translocated to 10, also known as AF10, a recurrent MLL partner. In this study, we found that MLLT10 promotes CRC tumor invasion and metastasis both in vitro and in vivo. Methods: Here, the expression of MLLT10 was evaluated by immunohistochemistry. Then, the plasmid and lentivirus particles for MLLT10 overexpression or knockdown were designed and constructed into SW620 and HT29 cells. Finally, cell proliferation assay, cell adhesion assay, transwell migration, and invasion assay were used to detect the migration and invasion ability of MLLT10 in CRC cells. A tail vein injection assay was employed to evaluate the role of MLLT10 in tumor metastases. Results: MLLT10 expression was significantly higher in CRC tissues than in noncancerous tissues and was associated with some clinicopathological factors. In vitro, the overexpression of MLLT10 promoted CRC cell migration and invasion, while after MLLT10 was knocked down, the opposite results were observed. Furthermore, we used animal metastasis models to detect the function of MLLT10 in vivo, the results are same with the outcomes in vitro. In lung metastasis sites, the knockdown of MLLT10 in SW620 cells significantly inhibited Vimentin expression, whereas the E-Cadherin was increased. Conclusions: These results indicate that MLLT10 regulates the metastasis of CRC cells via EMT. [ABSTRACT FROM AUTHOR]

Intersection relations are important topological considerations in database update processes. The differentiation and identification of non-empty intersection relations between new updates and existing objects is one of the first steps in the automatic incremental update process for a land parcel database. The basic non-empty intersection relations are meet, overlap, cover, equal and inside, but these basic relationships cannot reflect the complex and detailed non-empty relations between a new update and the existing objects. It is therefore necessary to refine the basic non-empty topological relations to support and trigger the relevant update operations. Such relations have been refined by several researchers using topological invariants (e.g., dimension, type and sequence) to represent the intersection components. However, the intersection components often include only points and lines, and the refined types of 2-dimensional intersection components that occur between land parcels have not been defined. This study examines the refinement of non-empty relations among 2-dimensional land parcels and proposes a computation model. In this model, an entire spatial object is directly used as the operand, and two set operations (i.e., intersection (∩) and difference (\)) are applied to form the basic topological computation model. The Euler number is introduced to refine the relations with a single 2-dimensional intersection (i.e., cover, inside and overlap) and to distinguish the refined types of 2-dimensional intersection components for the relations with multiple intersections. In this study, the cover and overlap relations with single intersections between regions are refined into seven cases, and nine basic types of 2-dimensional intersection components are distinguished. A composite computation model is formed with both Euler number values and dimensional differences. In this model, the topological relations with single intersections are differentiated by the value of the dimension and the Euler number of the resulting set of the whole-object intersection and differences, whereas the relations with multiple intersections are discriminated by the value of the resulting set at a coarse level and are further differentiated by the type and sequence of the whole-object intersection component in a hierarchical manner. Based on the refined topological relations, an improved method for automatic and incremental updating of the land parcel database is presented. The effectiveness of the models and algorithms was verified by the incremental update of a land cover database. The results of this study represent a new avenue for automatic spatial data handling in incremental update processes. [ABSTRACT FROM PUBLISHER]

In this article, optimal error estimates of the penalty method for the linearized viscoelastic flows equations arising in the Oldroyd model are derived. Furthermore, error estimates for the backward Euler time discretization scheme in L2 and H1-norms are obtained. [ABSTRACT FROM AUTHOR]

Folate receptor 4 (FR4) is recently found as a lymphoid tissue specific protein. In this study, we have identified an alternative splicing variant of the FR4 gene from murine splenocytes, termed FR4v, which is almost identical to FR4 cDNA sequence except with the retained 108 bp intron 3 between exon 3 and 4 of FR4 gene. FR4v mRNA encodes a larger protein than FR4 and is constitutively expressed on CD4+CD25+ regulatory T cell (Treg) membrane via a GPI anchor mechanism. Whether FR4v plays a redundant or unique functional role in Tregs should be investigated further in the future. [ABSTRACT FROM AUTHOR]

In this study, the complete mitochondrial genome sequence of black-footed ferret,Mustela nigripes, is determined for the first time. This mitogenome is 16,556 bp in length and contains 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes, and 1 control region (D-loop). The overall base composition is A (32.9%), C (26.1%), G (13.8%), and T (27.2%), so the percentage of A and T (60.1%) is higher than that of G and C. Most of the genes are encoded on H-strand, except for theND6subunit gene and six tRNA genes. The complete mitochondrial genome sequence reported here would be useful for further phylogenetic analysis and conservation genetic studies inM. nigripes. [ABSTRACT FROM PUBLISHER]

In this study, the complete mitochondrial genome sequence of Algerian honeybee,Apis mellifera intermissa, is analyzed for the first time. The results show that this genome is 16,336 bp in length, and contains 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes, and 1 control region (D-loop). The overall base composition is A (43.2%), C (9.8%), G (5.6%), and T (41.4%), so the percentage of A and T (84.6%) is considerably higher than that of G and C. All the genes are encoded on H-strand, except for four subunit genes (ND1, ND4, ND4L, andND5), two rRNA genes (12Sand16S rRNA), and eight tRNA genes. The complete mitochondrial genome sequence reported here would be useful for further phylogenetic analysis and conservation genetic studies inA. m. intermissa. [ABSTRACT FROM PUBLISHER]

A correction to the article on the multiple administrations of human marrow stromal cells through cerebrospinal fluid prolong survival in a transgenic mouse model of amyotrophic lateral sclerosis in the May 2009 issue is presented.