447 research outputs found
Hybrid Model for the Analysis of Human Gait: A Non-linear Approach
In this work, a generalization of the study of the human gait was made from already
existent models in the literature, like models of Keller and Kockshenev. In this hybrid model, a
strategy of metabolic energy minimization is combined in a race process, with a non-linear
description of the movement of the mass centerâs libration, trying to reproduce the behavior of
the walk-run transition. The results of the experimental data, for different speed regimes, indicate
that the perimeter of the trajectory of the mass center is a relevant quantity in the quantification
of this dynamic. An experimental procedure was put into practice in collaboration with the
research group in Biomedical Engineering, Basic Sciences and Laboratories of the Manuela BeltrĂĄn
University in BogotĂĄ, Colombia
Body composition, nutritional profile and muscular fitness affect bone health in a sample of schoolchildren from Colombia: The Fuprecol Study
This is the final version of the article. Available from the publisher via the DOI in this record.The objective of the present study is to investigate the relationships between body
composition, nutritional profile, muscular fitness (MF) and bone health in a sample of children
and adolescents from Colombia. Participants included 1118 children and adolescents (54.6% girls).
Calcaneal broadband ultrasound attenuation (c-BUA) was obtained as a marker of bone health.
Body composition (fat mass and lean mass) was assessed using bioelectrical impedance analysis.
Furthermore height, weight, waist circumference and Tanner stage were measured and body mass
index (BMI) was calculated. Standing long-jump (SLJ) and isometric handgrip dynamometry were
used respectively as indicators of lower and upper body muscular fitness. A muscular index score
was also computed by summing up the standardised values of both SLJ and handgrip strength.
Dietary intake and degree of adherence to the Mediterranean diet were assessed by a 7-day recall
questionnaire for food frequency and the Kidmed questionnaire. Poor bone health was considered
using a z-score cut off of â€â1.5 standard deviation. Once the results were adjusted for age and
Tanner stage, the predisposing factors of having a c-BUA z-score â€â1.5 standard deviation included
being underweight or obese, having an unhealthy lean mass, having an unhealthy fat mass, SLJ
performance, handgrip performance, and unhealthy muscular index score. In conclusion, body
composition (fat mass and lean body mass) and MF both influenced bone health in a sample of
children and adolescents from Colombia. Thus promoting strength adaptation and preservation in
Colombian youth will help to improve bone health, an important protective factor against osteoporosis
in later life.: We would like to acknowledge to Bogota District Education Department for supporting data
collection for this study. The authors also thank the participating Bogota District students, teachers, schools, and
staff. The âFUPRECOL Studyâ was possible given the financial support provided by the Instituto Colombiano
para el Desarrollo de la Ciencia y la TecnologĂa âFrancisco JosĂ© de Caldasâ COLCIENCIAS (Contract Number
671-2014 Code 122265743978). Also, during the completion of this paper, AG-H was visiting researchers at
the University of Rosario (CEMA, BogotĂĄ, Colombia), supported with grants awarded by Proyectos Basales y
VicerrectorĂa de InvestigaciĂłn, Desarrollo e InnovaciĂłnâ (Universidad de Santiago de Chile, USACH)
Novel insights into host-fungal pathogen interactions derived from live-cell imaging
Acknowledgments The authors acknowledge funding from the Wellcome Trust (080088, 086827, 075470 and 099215) including a Wellcome Trust Strategic Award for Medical Mycology and Fungal Immunology 097377 and FP7-2007â2013 grant agreement HEALTH-F2-2010-260338âALLFUN to NARG.Peer reviewedPublisher PD
Updating known distribution models for forecasting climate change impact on endangered species
To plan endangered species conservation and to design adequate management programmes, it is necessary to predict their
distributional response to climate change, especially under the current situation of rapid change. However, these
predictions are customarily done by relating de novo the distribution of the species with climatic conditions with no regard
of previously available knowledge about the factors affecting the species distribution. We propose to take advantage of
known species distribution models, but proceeding to update them with the variables yielded by climatic models before
projecting them to the future. To exemplify our proposal, the availability of suitable habitat across Spain for the endangered
Bonelliâs Eagle (Aquila fasciata) was modelled by updating a pre-existing model based on current climate and topography to
a combination of different general circulation models and Special Report on Emissions Scenarios. Our results suggested that
the main threat for this endangered species would not be climate change, since all forecasting models show that its
distribution will be maintained and increased in mainland Spain for all the XXI century. We remark on the importance of
linking conservation biology with distribution modelling by updating existing models, frequently available for endangered
species, considering all the known factors conditioning the speciesâ distribution, instead of building new models that are
based on climate change variables only.Ministerio de Ciencia e InnovaciĂłn and FEDER (project CGL2009-11316/BOS
Use of facile mechanochemical method to functionalize carbon nanofibers with nanostructured polyaniline and their electrochemical capacitance
A facile approach to functionalize carbon nanofibers [CNFs] with nanostructured polyaniline was developed via in situ mechanochemical polymerization of polyaniline in the presence of chemically treated CNFs. The nanostructured polyaniline grafting on the CNF was mainly in a form of branched nanofibers as well as rough nanolayers. The good dispersibility and processability of the hybrid nanocomposite could be attributed to its overall nanostructure which enhanced its accessibility to the electrolyte. The mechanochemical oxidation polymerization was believed to be related to the strong Lewis acid characteristic of FeCl3 and the Lewis base characteristic of aniline. The growth mechanism of the hierarchical structured nanofibers was also discussed. After functionalization with the nanostructured polyaniline, the hybrid polyaniline/CNF composite showed an enhanced specific capacitance, which might be related to its hierarchical nanostructure and the interaction between the aromatic polyaniline molecules and the CNFs
Knowledge, attitudes and practice survey about antimicrobial resistance and prescribing among physicians in a hospital setting in Lima, Peru
BACKGROUND: Misuse of antimicrobials (AMs) and antimicrobial resistance (AMR) are global concerns. The present study evaluated knowledge, attitudes and practices about AMR and AM prescribing among medical doctors in two large public hospitals in Lima, Peru, a middle-income country. METHODS: Cross-sectional study using a self-administered questionnaire RESULTS: A total of 256 participants completed the questionnaire (response rate 82%). Theoretical knowledge was good (mean score of 6 +/- 1.3 on 7 questions) in contrast to poor awareness (< 33%) of local AMR rates of key-pathogens. Participants strongly agreed that AMR is a problem worldwide (70%) and in Peru (65%), but less in their own practice (22%). AM overuse was perceived both for the community (96%) and the hospital settings (90%). Patients' pressure to prescribing AMs was considered as contributing to AM overuse in the community (72%) more than in the hospital setting (50%). Confidence among AM prescribing was higher among attending physicians (82%) compared to residents (30%, p < 0.001%). Sources of information considered as very useful/useful included pocket-based AM prescribing guidelines (69%) and internet sources (62%). Fifty seven percent of participants regarded AMs in their hospitals to be of poor quality. Participants requested more AM prescribing educational programs (96%) and local AM guidelines (92%). CONCLUSIONS: This survey revealed topics to address during future AM prescribing interventions such as dissemination of information about local AMR rates, promoting confidence in the quality of locally available AMs, redaction and dissemination of local AM guidelines and addressing the general public, and exploring the possibilities of internet-based training
Simplifying the detection of MUTYH mutations by high resolution melting analysis
<p>Abstract</p> <p>Background</p> <p><it>MUTYH</it>-associated polyposis (MAP) is a disorder caused by bi-allelic germline <it>MUTYH </it>mutation, characterized by multiple colorectal adenomas. In order to identify mutations in <it>MUTYH </it>gene we applied High Resolution Melting (HRM) genotyping. HRM analysis is extensively employed as a scanning method for the detection of heterozygous mutations. Therefore, we applied HRM to show effectiveness in detecting homozygous mutations for these clinically important and frequent patients.</p> <p>Methods</p> <p>In this study, we analyzed phenotype and genotype data from 82 patients, with multiple (>= 10) synchronous (19/82) or metachronous (63/82) adenomas and negative <it>APC </it>study (except one case). Analysis was performed by HRM-PCR and direct sequencing, in order to identify mutations in <it>MUTYH </it>exons 7, 12 and 13, where the most prevalent mutations are located. In monoallelic mutation carriers, we evaluated entire <it>MUTYH </it>gene in search of another possible alteration. HRM-PCR was performed with strict conditions in several rounds: the first one to discriminate the heteroduplex patterns and homoduplex patterns and the next ones, in order to refine and confirm parameters. The genotypes obtained were correlated to phenotypic features (number of adenomas (synchronous or metachronous), colorectal cancer (CRC) and family history).</p> <p>Results</p> <p><it>MUTYH </it>germline mutations were found in 15.8% (13/82) of patients. The hot spots, Y179C (exon 7) and G396D (exon 13), were readily identified and other mutations were also detected. Each mutation had a reproducible melting profile by HRM, both heterozygous mutations and homozygous mutations. In our study of 82 patients, biallelic mutation is associated with being a carrier of â„10 synchronous polyps (p = 0.05) and there is no association between biallelic mutation and CRC (p = 0.39) nor family history (p = 0.63). G338H non-pathogenic polymorphism (exon 12) was found in 23.1% (19/82) of patients. In all cases there was concordance between HRM (first and subsequent rounds) and sequencing data.</p> <p>Conclusions</p> <p>Here, we describe a screening method, HRM, for the detection of both heterozygous and homozygous mutations in the gene encoding <it>MUTYH </it>in selected samples of patients with phenotype of MAP. We refine the capabilities of HRM-PCR and apply it to a gene not yet analyzed by this tool. As clinical decisions will increasingly rely on molecular medicine, the power of identifying germline mutations must be continuously evaluated and improved.</p
Estimating how inflated or obscured effects of climate affect forecasted species distribution
Climate is one of the main drivers of species distribution. However, as different environmental factors tend to co-vary, the
effect of climate cannot be taken at face value, as it may be either inflated or obscured by other correlated factors. We used
the favourability models of four species (Alytes dickhilleni, Vipera latasti, Aquila fasciata and Capra pyrenaica) inhabiting
Spanish mountains as case studies to evaluate the relative contribution of climate in their forecasted favourability by using
variation partitioning and weighting the effect of climate in relation to non-climatic factors. By calculating the pure effect of
the climatic factor, the pure effects of non-climatic factors, the shared climatic effect and the proportion of the pure effect of
the climatic factor in relation to its apparent effect (r), we assessed the apparent effect and the pure independent effect of
climate. We then projected both types of effects when modelling the future favourability for each species and combination
of AOGCM-SRES (two Atmosphere-Ocean General Circulation Models: CGCM2 and ECHAM4, and two Special Reports on
Emission Scenarios (SRES): A2 and B2). The results show that the apparent effect of climate can be either inflated (overrated)
or obscured (underrated) by other correlated factors. These differences were species-specific; the sum of favourable areas
forecasted according to the pure climatic effect differed from that forecasted according to the apparent climatic effect by
about 61% on average for one of the species analyzed, and by about 20% on average for each of the other species. The pure
effect of future climate on species distributions can only be estimated by combining climate with other factors. Transferring
the pure climatic effect and the apparent climatic effect to the future delimits the maximum and minimum favourable areas
forecasted for each species in each climate change scenario.Ministerio de Ciencia e InnovaciĂłn and FEDER (project CGL2009-11316/BOS). D. Romero is a PhD student at the University of Malaga with a grant of the Ministerio de EducacioÂŽn y Ciencia (AP 2007-03633
Observation of associated near-side and away-side long-range correlations in âsNN=5.02ââTeV proton-lead collisions with the ATLAS detector
Two-particle correlations in relative azimuthal angle (ÎÏ) and pseudorapidity (Îη) are measured in âsNN=5.02ââTeV p+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using approximately 1ââÎŒb-1 of data as a function of transverse momentum (pT) and the transverse energy (ÎŁETPb) summed over 3.1<η<4.9 in the direction of the Pb beam. The correlation function, constructed from charged particles, exhibits a long-range (2<|Îη|<5) ânear-sideâ (ÎÏâŒ0) correlation that grows rapidly with increasing ÎŁETPb. A long-range âaway-sideâ (ÎÏâŒÏ) correlation, obtained by subtracting the expected contributions from recoiling dijets and other sources estimated using events with small ÎŁETPb, is found to match the near-side correlation in magnitude, shape (in Îη and ÎÏ) and ÎŁETPb dependence. The resultant ÎÏ correlation is approximately symmetric about Ï/2, and is consistent with a dominant cosâĄ2ÎÏ modulation for all ÎŁETPb ranges and particle pT
An Assessment of the Effectiveness of High Definition Cameras as Remote Monitoring Tools for Dolphin Ecology Studies.
Research involving marine mammals often requires costly field programs. This paper assessed whether the benefits of using cameras outweighs the implications of having personnel performing marine mammal detection in the field. The efficacy of video and still cameras to detect Indo-Pacific bottlenose dolphins (Tursiops aduncus) in the Fremantle Harbour (Western Australia) was evaluated, with consideration on how environmental conditions affect detectability. The cameras were set on a tower in the Fremantle Port channel and videos were perused at 1.75 times the normal speed. Images from the cameras were used to estimate position of dolphins at the waterâs surface. Dolphin detections ranged from 5.6 m to 463.3 m for the video camera, and from 10.8 m to 347.8 m for the still camera. Detection range showed to be satisfactory when compared to distances at which dolphins would be detected by field observers. The relative effect of environmental conditions on detectability was considered by fitting a Generalised Estimation Equations (GEEs) model with Beaufort, level of glare and their interactions as predictors and a temporal auto-correlation structure. The best fit model indicated level of glare had an effect, with more intense periods of glare corresponding to lower occurrences of observed dolphins. However this effect was not large (-0.264) and the parameter estimate was associated with a large standard error (0.113).The limited field of view was the main restraint in that cameras can be only applied to detections of animals observed rather than counts of individuals. However, the use of cameras was effective for long term monitoring of occurrence of dolphins, outweighing the costs and reducing the health and safety risks to field personal. This study showed that cameras could be effectively implemented onshore for research such as studying changes in habitat use in response to development and construction activities
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