Solving a generalized traveling salesperson problem with stochastic customers

In this paper, a probabilistic generalized traveling salesperson problem (PGTSP) is introduced to address several applications. In the PGTSP, each customer belongs to a cluster that consists of a set of customers. Whether or not any given customer will be present during actual operations is known a priori only probabilistically. The PGTSP seeks the minimum expected length tour to visit a subset of all customers such that the tour traverses each cluster at least once. If when implementing the tour it is revealed that there is no demand for service within the cluster to which a customer stop belongs, that stop will be skipped. An exact solution algorithm based on the integer L-shaped method and three tour construction-based heuristics for quickly solving this problem are described in the paper. Computational experiments were conducted to assess computational requirements and solution quality of the proposed solution techniques. These experiments show that the exact method is able to solve small- and moderate-size problems to optimality. In addition, one of the proposed heuristics (the MMI heuristic), in particular, gives good approximate solutions (often a few percent from optimal) in very reasonable computational time.     

Failure of Adhesive Bonds at Constant Strain Rates

Shear strengths of adhesive bonds using AF126 and two thicknesses of aluminum were measured at constant rate of crosshead separation. It was found that the shear strength could be related to temperature and strain rate or failure time over the range of deformation rates used.     

Microstructure and protein digestibility of beef: The effect of cooking conditions as used in stews and curries

Beef meat was cooked at 373 K for 10 and 30 min to investigate the effect of the cooking conditions generally used during beef stew and curry preparation on protein digestibility. The cooked meats, along with a raw control, were digested using an in vitro digestion model to simulate gastric and small-intestinal conditions. Samples taken at different digestion times were analyzed using SDS-PAGE, RP-HPLC, ninhydrin assays for amino N and transmission electron microscopy. Simulated gastric conditions quickly led to the loss of basic sarcomere structure in raw meat myofibrils whereas the sarcomere structure of the compact cooked meat myofibrils remained intact after 30 min of gastric digestion. Prolonged cooking of meat (30 min) resulted in incomplete digestion of small MW (<10 kDa) peptides, as observed from SDS-PAGE. This agreed with the amount of ninhydrin-reactive amino N released during digestion, which decreased with an increase in cooking time. The RP-HPLC peak areas of the major identified amino acids (tryptophan, tyrosine and phenylalanine) also decreased with an increase in cooking time. This suggested the formation of “limit peptides” during prolonged cooking of beef, which were not further broken down into free amino acids by digestive enzymes and therefore might not be bioavailable.     

Cancer Stem Cells: Biological Functions and Therapeutically Targeting

Almost all tumors are composed of a heterogeneous cell population, making them difficult to treat. A small cancer stem cell population with a low proliferation rate and a high tumorigenic potential is thought to be responsible for cancer development, metastasis and resistance to therapy. Stem cells were reported to be involved in both normal development and carcinogenesis, some molecular mechanisms being common in both processes. No less controversial, stem cells are considered to be important in treatment of malignant diseases both as targets and drug carriers. The efforts to understand the role of different signalling in cancer stem cells requires in depth knowledge about the mechanisms that control their self-renewal, differentiation and malignant potential. The aim of this paper is to discuss insights into cancer stem cells historical background and to provide a brief review of the new therapeutic strategies for targeting cancer stem cells.     

Configuration for mass customization: how to extend product configuration towards requirements and process configuration

In order to develop mass customization, many companies use configuration software to customize their products. Although many studies already exist about Product Configuration, Requirements and Process Configuration have not been studied in detail. As all these three aspects must be considered for mass customization, the aim of this paper is to show how Product Configuration, when considered as a constraint satisfaction problem, can be extended upstream towards Requirements Configuration and downstream towards Process Configuration. Product Configuration basics are first reviewed thanks to a constraint based approach, and an analysis of industrial configuration situations is done in order to clarify mass customization needs in terms of configuration. Then upstream Requirements Configuration and downstream Process Configuration are defined and generic models are proposed. It is shown that the proposed elements allow a global and consistent flow of configuration activities. A detailed example illustrates the different configuration problems and a discussion terminates the paper.     

Delineation of the genomics field by hybrid citation-lexical methods: interaction with experts and validation process

In advanced methods of delineation and mapping of scientific fields, hybrid methods open a promising path to the capitalisation of advantages of approaches based on words and citations. One way to validate the hybrid approaches is to work in cooperation with experts of the fields under scrutiny. We report here an experiment in the field of genomics, where a corpus of documents has been built by a hybrid citation-lexical method, and then clustered into research themes. Experts of the field were associated in the various stages of the process: lexical queries for building the initial set of documents, the seed; citation-based extension aiming at reducing silence; final clustering to identify noise and allow discussion on border areas. The analysis of experts’ advices show a high level of validation of the process, which combines a high-precision and low-recall seed, obtained by journal and lexical queries, and a citation-based extension enhancing the recall. This findings on the genomics field suggest that hybrid methods can efficiently retrieve a corpus of relevant literature, even in complex and emerging fields.     

第二名悬式水园

在狭窄的长形场地上建造房子具有一定的难度,而在维也纳郊区的小斜坡上修建住宅区更是难上加难,林木繁茂的陡峭崖径把道路和建筑用地分隔开来,为设计增添了新的难题.     

旅行花园

一位"植物猎人"在维也纳第三区的一个公寓屋顶创造了他的天堂。公寓的主人同意他暂时使用屋顶,但必须保证使用期限到时,花园可以容易地进行清理。一个低造价的简易软木结构牢固地悬挂在屋顶上,这样负荷就不会直接传给下面的屋顶。冬天来临时,可以用背包把花盆里的植物搬到屋子里。背包其实是一种叫做"Buckelkraxen"的传统搬运工具,它常为奥地利阿尔卑斯山上的农夫们所使用。因此,除了少数种类外,大多数植物只有在夏天的时候,才会留在屋顶上。这个花园还有另外一个好处:园丁可以随性改变植物的摆放位置。设计者筛选植物的最重要标准是香味、气氛和     

Novel TTLL5 Variants Associated with Cone-Rod Dystrophy and Early-Onset Severe Retinal Dystrophy

Variants of the TTLL5 gene, which encodes tubulin tyrosine ligase-like family member five, are a rare cause of cone dystrophy (COD) or cone-rod dystrophy (CORD). To date, only a few TTLL5 patients have been clinically and genetically described. In this study, we report five patients harbouring biallelic variants of TTLL5. Four adult patients presented either COD or CORD with onset in the late teenage years. The youngest patient had a phenotype of early onset severe retinal dystrophy (EOSRD). Genetic analysis was performed by targeted next generation sequencing of gene panels and assessment of copy number variants (CNV). We identified eight variants, of which six were novel, including two large multiexon deletions in patients with COD or CORD, while the EOSRD patient harboured the novel homozygous p.(Trp640*) variant and three distinct USH2A variants, which might explain the observed rod involvement. Our study highlights the role of TTLL5 in COD/CORD and the importance of large deletions. These findings suggest that COD or CORD patients lacking variants in known genes may harbour CNVs to be discovered in TTLL5, previously undetected by classical sequencing methods. In addition, variable phenotypes in TTLL5-associated patients might be due to the presence of additional gene defects.     

Facilitating communication about books through an online community

Reading books can serve as a means of gathering information, relaxing and escaping daily stress. Although reading is often primarily an individual activity, many readers also enjoy sharing reading experiences with friends, relatives, colleagues and, through the internet, even with strangers. Apart from valuing these individual and collective book activities, books as physical artifacts are also valued, for example because of the memories associated with them. This paper investigates how books can be enhanced with a new product, system or service. In a qualitative interview study, the main reasons for valuing books were found to be related to the self (individual activities and feelings), experiences (e.g., enjoyment or release) and personal values (e.g., embodiment of ideals or personification). As a result, it was decided for the remainder of this study to focus on communication about books, because in addition to individual book-related activities and feelings, users indicated to communicate about books a lot. A book community Web site, called Shelf, was developed to investigate whether book communication could be increased by facilitating an online community and whether users would appreciate the Web site functionality. Shelf was used in a 14-day user evaluation, and it was concluded that the Web site increased the extent to which readers communicated about books. We expect that such an online book community would be a valuable enhancement of current book customs, in particular in combination with the current e-book trend, for various types of readers who would like to share their experiences.