Search results for " linkage"
showing 10 items of 174 documents
Synthesis and characterization of nanomaterial based on halloysite and hectorite clay minerals covalently bridged
2021
Halloysite is an aluminosilicate clay with a predominantly hollow tubular structure (HNTs) able to act as a nanocontainer for the encapsulation of several chemicals. However, HNTs possess low affinity for metal ions in their pristine form and they need to be modified for improving their adsorption capabilities. Therefore, to overcome this issue herein we report a straightforward approach for the covalent modification of the external surface of halloysite nanotubes with hectorite clay. Compared to halloysite, hectorite possesses a lamellar structure with higher cation exchange capacity. The covalent linkage between the two clays was verified by several techniques (FTIR spectroscopy, 13C CP-M…
Population structure in the Méditerranean basin: a Y chromosome perspective
2006
The Mediterranean region has been characterised by a number of pre-historical and historical demographic events whose legacy on the current genetic landscape is still a matter of debate. In order to investigate the degree of population structure across the Mediterranean, we have investigated Y chromosome variation in a large dataset of Mediterranean populations, 11 of which are first described here. Our analyses identify four main clusters in the Mediterranean that can be labelled as North Africa, Arab, Central-East and West Mediterranean. In particular, Near Eastern samples tend to separate according to the presence of Arab Y chromosome lineages, suggesting that the Arab expansion played a…
Using genetically-defined rodent strains for the identification of hippocampal traits relevant for two-way avoidance behavior: a non-invasive approach
1989
Genetically-defined rodent strains permit the identification of hippocampal traits which are of functional relevance for the performance of two-way avoidance behavior. This is exemplified here by analyzing the relationship between infrapyramidal mossy fibers (a tiny projection terminating upon the basal dendrites of hippocampal pyramidal neurons) and two-way avoidance learning in about 800 animals. The necessary steps include 1) identification of structural traits sensitive to selective breeding for extremes in two-way avoidance, 2) testing the robustness of the associations found by studying individual and genetical correlations between hippocampal traits and behavior, 3) establishing caus…
Network governance arrangements and rural-urban synergy
2021
Increasing attention has been paid to the importance of balanced rural–urban interaction to sustainable regional development. Yet, our knowledge on the elements of network governance for such interaction is scarce. The aim of this paper is to study what kind of network governance arrangements currently exist, how they can be improved, and whether evolutionary governance paths can be identified. We analyse five existing and evolving cases of functioning rural–urban interaction in European Union (EU) member states, using a network governance framework as an analytical lens. We supplement the governance analysis with examining what kind of spatial understanding or combination of di…
Early-onset ataxia with cardiomyopathy and retained tendon reflexes maps to the friedreich's ataxia locus on chromosome 9q
1995
Absence of lower limb tendon reflexes has been considered an essential diagnostic criterion for Friedreich's ataxia (FA). However, preservation of knee and ankle jerks has been reported in a few patients. Linkage analysis to FA locus (FRDA) on chromosome 9q13-21.1 was performed in 11 patients from 6 families with FA phenotype, including cardiomyopathy, but retained reflexes (FARR). A maximal lod score of 3.38 at recombination fraction theta equal to 0.00 was obtained demonstrating that FARR maps to the FRDA locus. These results suggest that FARR is a variant phenotype of FA.
Bagging, bumping, multiview, and active learning for record linkage with empirical results on patient identity data
2011
Record linkage or deduplication deals with the detection and deletion of duplicates in and across files. For this task, this paper introduces and evaluates two new machine-learning methods (bumping and multiview) together with bagging, a tree-based ensemble-approach. Whereas bumping represents a tree-based approach as well, multiview is based on the combination of different methods and the semi-supervised learning principle. After providing a theoretical background of the methods, initial empirical results on patient identity data are given. In the empirical evaluation, we calibrate the methods on three different kinds of training data. The results show that the smallest training data set, …
Late Cardiac Events after Childhood Cancer: Methodological Aspects of the Pan-European Study PanCareSurFup.
2016
Background and AimChildhood cancer survivors are at high risk of long-term adverse effects of cancer and its treatment, including cardiac events. The pan-European PanCareSurFup study determined the incidence and risk factors for cardiac events among childhood cancer survivors. The aim of this article is to describe the methodology of the cardiac cohort and nested case-control study within PanCareSurFup.MethodsEight data providers in Europe participating in PanCareSurFup identified and validated symptomatic cardiac events in their cohorts of childhood cancer survivors. Data on symptomatic heart failure, ischemia, pericarditis, valvular disease and arrhythmia were collected and graded accordi…
Spanning Trees and bootstrap reliability estimation in correlation based networks
2007
We introduce a new technique to associate a spanning tree to the average linkage cluster analysis. We term this tree as the Average Linkage Minimum Spanning Tree. We also introduce a technique to associate a value of reliability to links of correlation based graphs by using bootstrap replicas of data. Both techniques are applied to the portfolio of the 300 most capitalized stocks traded at New York Stock Exchange during the time period 2001-2003. We show that the Average Linkage Minimum Spanning Tree recognizes economic sectors and sub-sectors as communities in the network slightly better than the Minimum Spanning Tree does. We also show that the average reliability of links in the Minimum …
722: Maternal solid organ transplantation and pregnancy outcome; a national population-based cohort study
2013
outcome; a national population-based cohort study Nils-Halvdan Morken, Cesar Diaz-Garcia, Mats Brannstrom University of Bergen, Public Health and Primary Health care, Bergen, Norway, University of Valencia, Gynecology and Obstetrics, Valencia, Spain, University of Gothenburg, Obstetrics and Gynecology, Valencia, Sweden OBJECTIVE: The first pregnancy with a live birth after solid organ transplantation in the human occurred more than 50 years ago. Still, knowledge about this very special patient group is limited. The objective was to assess the risk of adverse pregnancy outcome after transplant compared to pregnancies before transplant in females. We also compared the risk after transplant wi…
Linkage analysis and disease models in benign familial infantile seizures: a study of 16 families.
2006
Summary: Purpose: Benign familial infantile seizures (BFIS) is a genetically heterogeneous condition characterized by partial seizures, onset age from 3 to 9 months, and favorable outcome. BFIS loci were identified on chromosomes 19q12-13.1 and 16p12-q12, allelic to infantile convulsions and choreathetosis. The identification of SCN2A mutations in families with only infantile seizures indicated that BFNIS and BFIS may show overlapping clinical features. Infantile seizures also were in a family with familial hemiplegic migraine and mutations in the ATP1A2 gene. We have examined the heterogeneous genetics of BFIS by means of linkage analysis. Methods: Sixteen families were examined. Probands …