Variable neighbourhood search for the minimum labelling Steiner tree problem

We present a study on heuristic solution approaches to the minimum labelling Steiner tree problem, an NP-hard graph problem related to the minimum labelling spanning tree problem. Given an undirected labelled connected graph, the aim is to find a spanning tree covering a given subset of nodes of the graph, whose edges have the smallest number of distinct labels. Such a model may be used to represent many real world problems in telecommunications and multimodal transportation networks. Several metaheuristics are proposed and evaluated. The approaches are compared to the widely adopted Pilot Method and it is shown that the Variable Neighbourhood Search that we propose is the most effective metaheuristic for the problem, obtaining high quality solutions in short computational running time

Heuristics based on greedy randomized adaptive search and variable neighbourhood search for the minimum labelling spanning tree problem

This paper studies heuristics for the minimum labelling spanning tree (MLST) problem. The purpose is to find a spanning tree using edges that are as similar as possible. Given an undirected labelled connected graph, the minimum labelling spanning tree problem seeks a spanning tree whose edges have the smallest number of distinct labels. This problem has been shown to be NP-complete. A Greedy Randomized Adaptive Search Procedure (GRASP) and different versions of Variable Neighbourhood Search (VNS) are proposed. They are compared with other algorithms recommended in the literature: the Modified Genetic Algorithm and the Pilot Method. Nonparametric statistical tests show that the heuristics based on GRASP and VNS outperform the other algorithms tested. Furthermore, a comparison with the results provided by an exact approach shows that we may quickly obtain optimal or near-optimal solutions with the proposed heuristics

SELECTIVIDAD DE LAS ISOFORMAS DE 140-180 KDA DE NCAM EN LA PAPILA ÓPTICA DEL EMBRIÓN DE POLLO

During embryonic development of chicken retina and retinotectal proyection, neural cells showed spatiotemporal patterns in the glycosidic residues located in the plasmatic membranes. Those glycidic components are related with adhesion and recognition cellular behaviours during the generation of nervous system cytoarchitecture. Thus those sugars are included both in usual glycoproteins as in a group of molecules called as cell adhesion molecules (CAM). The first isolated molecule in this group was the neural cell adhesion molecule (NCAM). This glycoprotein has a proteic core with diverse isoforms and it has a variable sialic acids chain. It was able to determine that 120 kDa NCAM isoform shows scarcely sialized chains in intermediate stages by using conventional techniques, lectins and immunohistochemistry. Meanwhile 140-180 kDa NCAM isoforms possess high content in sialic acid and they are present both in early and final stages. Other authors reported that human 120 kDa NCAM isoform was similar to that observed in the Gallus domesticus retina. Our results showed that 140- 180kDa isoforms were only presented in the nerve optic fibers when they were left the optic disc.Durante la embriogénesis de la retina del Gallus domesticus, los neuroblastos muestran variaciones temporales y espaciales de los residuos glucosilados a nivel de sus membranas plasmáticas. Se considera que estos componentes glucídicos están implicados en la organización de estructuras neurales inmaduras, mediante su participación en mecanismos de reconocimiento y adhesión celulares. Los componentes glucosilados van a formar parte de glucoproteínas convencionales, así como de un grupo de moléculas a las que genéricamente se han denominado moléculas de adhesión celular. La primera de estas moléculas aislada fue la neural cell adhesion molecule (NCAM), glucoproteína compuesta por un armazón proteico con diversas isoformas y una cadena más o menos variable de polímeros de ácidos siálicos. La combinación de técnicas convencionales his- toquímicas, de lectinas e inmunocitoquímicas han permitido determinar que las moléculas de NCAM de 120 kDa presentan cadenas pobremente sializadas en estadíos intermedios del desarrollo, mientras en estadíos tempranos y finales los ácidos siálicos están más abundantemente representados en las isoformas de 140-180 kDa. Algunos autores han determinado que la isoforma de NCAM presente durante el desarrollo de la retina del Gallus domesticus es similar a la humana de 120 kDa. Nuestros resultados indican que las isoformas de 140-180 kDa sólo se presentan en las fibras del nervio óptico una vez que estas abandonan la papila óptica

A colorectal cancer susceptibility new variant at 4q26 in the Spanish population identified by genome-wide association analysis

This work was partially supported by the CENIT program from the Centro Tecnológico Industrial (CEN-20091016), grants from the Spanish Institute of Health Carlos III (ADE10/00026, PI09/02444, PI12/00511, Acción Transversal de Cáncer) grants from the Fondo de Investigacion Sanitaria/FEDER (08/1276, 08/0024, PS09/02368, 11/00219, 11/00681), and by COST office through COST action BM1206. SCB is supported by contracts from the Fondo de Investigación Sanitaria (CP 03-0070). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Centro Tecnológico IndustrialInstituto de Salud Carlos IIIFondo de Investigación Sanitaria / FEDE

Mortality by causes in HIV-infected adults: comparison with the general population

<p>Abstract</p> <p>Background</p> <p>We compared mortality by cause of death in HIV-infected adults in the era of combined antiretroviral therapy with mortality in the general population in the same age and sex groups.</p> <p>Methods</p> <p>Mortality by cause of death was analyzed for the period 1999-2006 in the cohort of persons aged 20-59 years diagnosed with HIV infection and residing in Navarre (Spain). This was compared with mortality from the same causes in the general population of the same age and sex using standardized mortality ratios (SMR).</p> <p>Results</p> <p>There were 210 deaths among 1145 persons diagnosed with HIV (29.5 per 1000 person-years). About 50% of these deaths were from AIDS. Persons diagnosed with HIV infection had exceeded all-cause mortality (SMR 14.0, 95% CI 12.2 to 16.1) and non-AIDS mortality (SMR 6.9, 5.7 to 8.5). The analysis showed excess mortality from hepatic disease (SMR 69.0, 48.1 to 78.6), drug overdose or addiction (SMR 46.0, 29.2 to 69.0), suicide (SMR 9.6, 3.8 to 19.7), cancer (SMR 3.2, 1.8 to 5.1) and cardiovascular disease (SMR 3.1, 1.3 to 6.1). Mortality in HIV-infected intravenous drug users did not change significantly between the periods 1999-2002 and 2003-2006, but it declined by 56% in non-injecting drug users (<it>P </it>= 0.007).</p> <p>Conclusions</p> <p>Persons with HIV infection continue to have considerable excess mortality despite the availability of effective antiretroviral treatments. However, excess mortality in the HIV patients has declined since these treatments were introduced, especially in persons without a history of intravenous drug use.</p

Transcriptome profiling of grapevine seedless segregants during berry development reveals candidate genes associated with berry weight

Indexación: Web of Science; PubMedBackground Berry size is considered as one of the main selection criteria in table grape breeding programs. However, this is a quantitative and polygenic trait, and its genetic determination is still poorly understood. Considering its economic importance, it is relevant to determine its genetic architecture and elucidate the mechanisms involved in its expression. To approach this issue, an RNA-Seq experiment based on Illumina platform was performed (14 libraries), including seedless segregants with contrasting phenotypes for berry weight at fruit setting (FST) and 6–8 mm berries (B68) phenological stages. Results A group of 526 differentially expressed (DE) genes were identified, by comparing seedless segregants with contrasting phenotypes for berry weight: 101 genes from the FST stage and 463 from the B68 stage. Also, we integrated differential expression, principal components analysis (PCA), correlations and network co-expression analyses to characterize the transcriptome profiling observed in segregants with contrasting phenotypes for berry weight. After this, 68 DE genes were selected as candidate genes, and seven candidate genes were validated by real time-PCR, confirming their expression profiles. Conclusions We have carried out the first transcriptome analysis focused on table grape seedless segregants with contrasting phenotypes for berry weight. Our findings contributed to the understanding of the mechanisms involved in berry weight determination. Also, this comparative transcriptome profiling revealed candidate genes for berry weight which could be evaluated as selection tools in table grape breeding programs.http://bmcplantbiol.biomedcentral.com/articles/10.1186/s12870-016-0789-

Influence of sex, age, pubertal maturation and body mass index on circulating white blood cell counts in healthy European adolescents—the HELENA study

Percentiles 10th, 25th, 50th, 75th and 90th are presented for circulating white blood cells (WBC), neutrophils, lymphocytes, monocytes, eosinophils and basophils in healthy European adolescents (12.5–17.5 years, n = 405, 48.9 % boys), considering age, sex, puberty and body mass index (BMI). CD3+ (mature T cells), CD4+ (T helper), CD8+ (T cytotoxic), CD16+56+ (natural killer), CD19+ (B cells), CD3+CD45RA+, CD4+CD45RA+, CD8+CD45RA+ (naïve), CD3+CD45RO+, CD4+CD45RO+ and CD8+CD45RO+ (memory) lymphocytes were also analysed by immunophenotyping. Girls presented higher WBC, neutrophil, CD3+CD45RO+ and CD4+CD45RO+ cell counts and CD3+/CD19+ ratio, and lower CD3+CD45RA+ and CD4+CD45RA+ counts than boys. Age was associated with higher neutrophil counts and CD3+/CD19+, and lower CD19+ counts; in boys, with lower CD3+CD45RA+, CD4+CD45RA+ and CD8+CD45RA+ counts as well; in girls, with higher WBC, CD3+CD45RO+ and CD4+CD45RO+ counts. Pubertal maturation in boys was associated with lower WBC and lymphocyte counts; in girls, with higher basophil, CD3+CD45RO+ and CD4+CD45RO+ values. BMI was associated with higher WBC counts; in boys, also with higher lymphocyte counts; in girls, with higher neutrophil, CD4+, CD3+CD45RO+ and CD4+CD45RO+ counts. Conclusion: Our study provides normative values for circulating immune cells in adolescents, highlighting the importance of considering sex, age, pubertal maturation and BMI when establishing reference ranges for WBC in paediatric populations

New regulations regarding Postgraduate Medical Training in Spain: perception of the tutor's role in the Murcia Region

<p>Abstract</p> <p>Background</p> <p>Recently introduced regulatory changes have expanded the Tutor role to include their primary responsibility for Postgraduate Medical Training (PMT). However, accreditation and recognition of that role has been devolved to the autonomic regions. The opinions of the RT may be relevant to future decisions;</p> <p>Methods</p> <p>A comprehensive questionnaire, including demographic characteristics, academic and research achievement and personal views about their role, was sent to 201 RTs in the Murcia Region of Spain. The responses are described using median and interquartile ranges (IQR);</p> <p>Results</p> <p>There were 147 replies (response rate 73%), 69% male, mean age 45 ± 7 yrs. RTs perception of the residents' initial knowledge and commitment throughout the program was 5 (IQR 4-6) and 7 (IQR 5-8), respectively. As regards their impact on the PMT program, RTs considered that their own contribution was similar to that of senior residents. RTs perception of how their role was recognised was 5 (IQR 3-6). Only 16% did not encounter difficulties in accessing specific RT training programs. Regarding the RTs view of their various duties, supervision of patient care was accorded the greatest importance (64%) while the satisfactory completion of the PMT program and supervision of day-to-day activities were also considered important (61% and 59% respectively). The main RT requirements were: a greater professional recognition (97%), protected time (95%), specific RT training programs (95%) and financial recognition (86%);</p> <p>Conclusions</p> <p>This comprehensive study, reflecting the feelings of our RTs, provides a useful insight into the reality of their work and the findings ought to be taken into consideration in the imminent definitive regulatory document on PMT.</p

Purification and biochemical characterization of four iron superoxide dismutases in Trypanosoma cruzi

Four superoxide dismutase (SOD) activities (SOD I, II, III, and IV) have been characterized in the epimastigote form of Trypanosoma cruzi . The total extract was subjected to two successive ammonium sulphate additions between 35 and 85%, and the resulting fraction was purified using two continuous chromatography processes (ion exchange and filtration). Enzymes were insensitive to cyanide but sensitive to hydrogen peroxide, properties characteristic of iron-containing SODs. The molecular masses of the different SODs were 20 kDa (SOD I), 60 kDa (SOD II), 50 kDa (SOD III) and 25 kDa (SOD IV), whereas the isoelectric points were 6.9, 6.8, 5.2 and 3.8, respectively. Subcellular location and digitonin experiments have shown that these SODs are mainly cytosolic, with small amounts in the low- mass organelles (SOD II and SOD I) and the mitochondrion (SOD III), where these enzymes play an important role in minimizing oxidative damage.Financial support: CGL2006-27889-E/BOS, Ministerio de Ciencia y Tecnología

Management Implications of the Biodiversity and Socio-Economic Impacts of Shrimp Trawler By-Catch in Bahía de Kino, Sonora, México

The shrimp fishery is the most economically important fishery in Mexico. The trawler-based portion of this fishery results in high rates of by-catch. This study quantifies and describes the biodiversity of by-catch associated with trawling in the Bahía de Kino region of Sonora, Mexico. Data were collected from 55 trawls, on six boats, over 14 nights, during November of 2003, 2004, 2006–2009. By-catch rates within trawl samples averaged 85.9% measured by weight. A total of 183 by-catch species were identified during the course of this study, including 97 species of bony fish from 43 families, 19 species of elasmobranchs from 12 families, 66 species of invertebrates from eight phyla, and one species of marine turtle; seven of the documented by-catch species are listed on the IUCN Red List, CITES, or the Mexican NOM-059-ECOL-2010; 35 species documented in the by-catch are also targeted by local artisanal fishers. Some of the species frequently captured as juveniles in the by-catch are economically important to small-scale fishers in the region, and are particularly sensitive to overexploitation due to their life histories. This study highlights the need for further research quantifying the impacts of high levels of by-catch upon small-scale fishing economies in the region and presents strong ecological and economic rationale for by-catch management within the shrimp fishery of the Gulf of California. Site-specific by-catch management plans should be piloted in the Bahía de Kino region to address the growing momentum in national and international fisheries policy regimes toward the reduction of by-catch in shrimp fisheries