350 research outputs found
Flow patterns generated by oblate medusan jellyfish: field measurements and laboratory analyses
Flow patterns generated by medusan swimmers such as
jellyfish are known to differ according the morphology of
the various animal species. Oblate medusae have been
previously observed to generate vortex ring structures
during the propulsive cycle. Owing to the inherent
physical coupling between locomotor and feeding
structures in these animals, the dynamics of vortex ring
formation must be robustly tuned to facilitate effective
functioning of both systems. To understand how this is
achieved, we employed dye visualization techniques on
scyphomedusae (Aurelia aurita) observed swimming in
their natural marine habitat. The flow created during each
propulsive cycle consists of a toroidal starting vortex
formed during the power swimming stroke, followed by a
stopping vortex of opposite rotational sense generated
during the recovery stroke. These two vortices merge in a
laterally oriented vortex superstructure that induces flow
both toward the subumbrellar feeding surfaces and
downstream. The lateral vortex motif discovered here
appears to be critical to the dual function of the medusa
bell as a flow source for feeding and propulsion.
Furthermore, vortices in the animal wake have a greater
volume and closer spacing than predicted by prevailing
models of medusan swimming. These effects are shown to
be advantageous for feeding and swimming performance,
and are an important consequence of vortex interactions
that have been previously neglected
Challenges in the care for consanguineous couples: an exploratory interview study among general practitioners and midwives
<p>Abstract</p> <p>Background</p> <p>It is often suggested that an effort must be made to increase awareness among consanguineous couples of their reproductive risk, and to refer them for genetic counseling if needed. Primary care professionals are considered most appropriate for addressing the subject and identifying couples at risk during consultations in their practice. This Dutch study aims to explore the experiences, attitudes and beliefs of such professionals regarding their care for consanguineous couples.</p> <p>Methods</p> <p>Sixteen semi-structured interviews were conducted with midwives and general practitioners.</p> <p>Results</p> <p>Although most primary care professionals considered it their task to inform couples about the risks of consanguinity, during consultations the topic was generally only briefly touched upon and quickly abandoned. Important reasons for this were professionals’ beliefs about religious and social values of couples, their low perception of the couples’ reproductive risk and expected limited feasibility of referral. Feelings of embarrassment regarding addressing consanguinity did not seem to play a significant role.</p> <p>Conclusions</p> <p>Primary care professional beliefs about their clients’ religious and social values, their attitudes toward the risk, and perceived limited options for referral seem to conflict with the professional norm to address the topic of consanguinity.</p
Educational paper: Imaging child abuse: the bare bones
Fractures are reported to be the second most common findings in child abuse, after skin lesions such as bruises and contusions. This makes careful interpretation of childhood fractures in relation to the provided clinical history important. In this literature review, we address imaging techniques and the prevailing protocols as well as fractures, frequently seen in child abuse, and the differential diagnosis of these fractures. The use of a standardised protocol in radiological imaging is stressed, as adherence to the international guidelines has been consistently poor. As fractures are a relatively common finding in childhood and interpretation is sometimes difficult, involvement of a paediatric radiologist is important if not essential. Adherence to international guidelines necessitates review by experts and is therefore mandatory. As in all clinical differential diagnoses, liaison between paediatricians and paediatric radiologists in order to obtain additional clinical information or even better having joint review of radiological studies will improve diagnostic accuracy. It is fundamental to keep in mind that the diagnosis of child abuse can never be solely based on radiological imaging but always on a combination of clinical, investigative and social findings. The quality and interpretation, preferably by a paediatric radiologist, of radiographs is essential in reaching a correct diagnosis in cases of suspected child abuse
An adaptive meta-search engine considering the user’s field of interest
AbstractExisting meta-search engines return web search results based on the page relevancy to the query, their popularity and content. It is necessary to provide a meta-search engine capable of ranking results considering the user’s field of interest. Social networks can be useful to find the users’ tendencies, favorites, skills, and interests. In this paper we propose MSE, a meta-search engine for document retrieval utilizing social information of the user. In this approach, each user is assumed to have a profile containing his fields of interest. MSE extracts main phrases from the title and short description of receiving results from underlying search engines. Then it clusters the main phrases by a Self-Organizing Map neural network. Generated clusters are then ranked on the basis of the user’s field of interest. We have compared the proposed MSE against two other meta-search engines. The experimental results show the efficiency and effectiveness of the proposed method
Security Applications for Converging Technologies - Impact on the Constitutional State and the Legal order
In this study we investigate the impact of converging technologies on legal practice and criminology in a forward looking study intended for practitioners and policy makers in the field of legislation, crime prevention, and law enforcement. We look at a 15 years timeframe and discuss the scientific and technical progress in various domains as well as the ethical, legal, and policy dilemmas involved.
№ 184. Ордер на обшук і арешт Костянтина Бутвиненка від 1 грудня 1937 р.
Objective: To examine attitudes and beliefs associated with changes in the intention to use benzodiazepines during the six-month period after first benzodiazepine use. Design: Population-based 6-month follow-up with 3 measurement points (baseline, 2 weeks after inclusion, 6 months after inclusion). Setting: Starting or initial benzodiazepine users were included during a period of 4 months from November 1994 in the only pharmacy of a Dutch community of 13,500 people. Measures: Variables proposed by the Model of Planned Behaviour and the Health Belief Model. Drug exposure data from automated pharmacy records. Results: At baseline, the intention to use benzodiazepines was primarily predicted by the perceived norm of the general practitioner regarding benzodiazepine use, and by the participants' own attitudes. After fourteen days, the determinants of change in the intention to use benzodiazepines were the initially perceived norm of the general practitioner and the change in the severity of participants' illnesses. After six months, the change in the severity of the illness and the perceived health benefits of benzodiazepines at the time of inclusion were the main determinants of the change in the intention to use benzodiazepines between the second and third measurement point. The intention to use benzodiazepines showed a decrease during follow-up. The three intention measures were significant predictors of actual benzodiazepine use during the year following baseline assessment. Conclusion: The study sheds light on interesting determinants of decrease or increase in the intention to use during the six-month period after first benzodiazepine use
Determining the genome-wide kinship coefficient seems unhelpful in distinguishing consanguineous couples with a high versus low risk for adverse reproductive outcome
Background: Offspring of consanguineous couples are at increased risk of congenital disorders. The risk increases as parents are more closely related. Individuals that have the same degree of relatedness according to their pedigree, show variable genomic kinship coefficients. To investigate whether we can differentiate between couples with high- and low risk for offspring with congenital disorders, we have compared the genomic kinship coefficient of consanguineous parents with a child affected with an autosomal recessive disorder with that of consanguineous parents with only healthy children, corrected for the degree of pedigree relatedness. Methods: 151 consanguineous couples (73 cases and 78 controls) from 10 different ethnic backgrounds were genotyped on the Affymetrix platform and passed quality control checks. After pruning SNPs in linkage disequilibrium, 57,358 SNPs remained. Kinship coefficients were calculated using three different toolsets: PLINK, King and IBDelphi, yielding five different estimates (IBDelphi, PLINK (all), PLINK (by population), King robust (all) and King homo (by population)). We performed a one-sided Mann Whitney test to investigate whether the median relative difference regarding observed and expected kinship coefficients is bigger for cases than for controls. Furthermore, we fitted a mixed effects linear model to correct for a possible population effect. Results: Although the estimated degrees of genomic relatedness with the different toolsets show substantial variability, correlation measures between the different estimators demonstrated moderate to strong correlations. Controls have higher point estimates for genomic kinship coefficients. The one-sided Mann Whitney test did not show any evidence for a higher median relative difference for cases compared to controls. Neither did the regression analysis exhibit a positive association between case–control status and genomic kinship coefficient. Conclusions: In this case–control setting, in which we compared consanguineous couples corrected for degree of pedigree relatedness, a higher degree of genomic relatedness was not significantly associated with a higher likelihood of having an affected child. Further translational research should focus on which parts of the genome and which pathogenic mutations couples are sharing. Looking at relatedness coefficients by determining genome-wide SNPs does not seem to be an effective measure for prospective risk assessment in consanguineous parents
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