838 resultados para Image-to-Image Variation


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This study had three objectives: (1) to develop a comprehensive truck simulation that executes rapidly, has a modular program construction to allow variation of vehicle characteristics, and is able to realistically predict vehicle motion and the tire-road surface interaction forces; (2) to develop a model of doweled portland cement concrete pavement that can be used to determine slab deflection and stress at predetermined nodes, and that allows for the variation of traditional thickness design factors; and (3) to implement these two models on a work station with suitable menu driven modules so that both existing and proposed pavements can be evaluated with respect to design life, given specific characteristics of the heavy vehicles that will be using the facility. This report summarizes the work that has been performed during the first year of the study. Briefly, the following has been accomplished: A two dimensional model of a typical 3-S2 tractor-trailer combination was created. A finite element structural analysis program, ANSYS, was used to model the pavement. Computer runs have been performed varying the parameters defining both vehicle and road elements. The resulting time specific displacements for each node are plotted, and the displacement basin is generated for defined vehicles. Relative damage to the pavement can then be estimated. A damage function resulting from load replications must be assumed that will be reflected by further pavement deterioration. Comparison with actual damage on Interstate 80 will eventually allow verification of these procedures.

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Background. The rarity of childhood cancers makes providing palliative care in the community an unusual event for primary care practitioners. Providing this care requires effective interprofessional collaboration with the team that forms to provide the care often working together for the first and only time. Objective. To explore the experiences of primary care practitioners following their involvement in the palliative care of a child with cancer at home. Methods. The study design was a community-based qualitative study. The study location was the West Midlands region. Purposeful sample of GPs and community nurses involved in providing palliative care to 12 children. One-to-one in-depth interviews with 47 primary care professionals (10 GPs and 37 community nurses) and 5 facilitated case discussions were undertaken. Field notes were documented and grounded theory data analysis undertaken: chronological comparative data analysis identifying generated themes. Results. GPs had minimal input into the preceding care of children undergoing treatment for cancer but sought to re-establish their role at the child’s transition to palliative care. GPs felt they had a role to play and could add value to this phase of care, highlighted their continuing role with the child’s family and acknowledged that they had gained from the experience of contributing. However, lack of specialist knowledge and uncertainty about their role within the team made this more challenging. In contrast, community nurses were routinely involved in both active treatment and palliation care phases. There was little evidence of collaboration between the specialist and primary care professionals involved. There was considerable variation in out of hours provision across cases. Conclusions. Engaging primary care practitioners needs to be more actively anticipated and negotiated at the transition to palliation. Variation in out of hours care is another cause for concern. Enhancing inter-professional collaboration and planning during both active and palliative care phases may help. Keywords. Cancer, family medicine, palliative care, paediatric.

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Fish is a valuable nutritional source witch use of it in daily meal has a beneficial role on nutritional needs supply and also causes mental and physical health especially in people who have protein and food deficiencies. Unfortunately, per capita consumption of sea foods in Iran is 5.5Kg witch is very lower than world standards. So, study on fish ice cream formulation, by use of fish protein concentrate (FPC) instead of milk protein, had done to make variation in sea foods products and also increase per capita consumption of these kinds of foods. FPC has very high protein concentration and a lot of necessary Also it's protein is very digestible amino acids like lysine and methionine with highly biological value and it's PER in compare with casein PER is high. At first fish protein concentrate type A produced from silver carp in three steps by the extraction with isopropyl alcohol solvent and heat. Microbiological and physicochemical specifications of produced FPC by rules of FDA and FAO were accepted. Finally according to panel test results, substitution of 30 percent of milk with FPC is acceptable. Also microbiological and physicochemical specifications of product were tested and results in compare with national standards of Iran were accepted.

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Hypertension is a major risk factor for cardiovascular disease and mortality, and a growing global public health concern, with up to one-third of the world’s population affected. Despite the vast amount of evidence for the benefits of blood pressure (BP) lowering accumulated to date, elevated BP is still the leading risk factor for disease and disability worldwide. It is well established that hypertension and BP are common complex traits, where multiple genetic and environmental factors contribute to BP variation. Furthermore, family and twin studies confirmed the genetic component of BP, with a heritability estimate in the range of 30-50%. Contemporary genomic tools enabling the genotyping of millions of genetic variants across the human genome in an efficient, reliable, and cost-effective manner, has transformed hypertension genetics research. This is accompanied by the presence of international consortia that have offered unprecedentedly large sample sizes for genome-wide association studies (GWASs). While GWAS for hypertension and BP have identified more than 60 loci, variants in these loci are associated with modest effects on BP and in aggregate can explain less than 3% of the variance in BP. The aims of this thesis are to study the genetic and environmental factors that influence BP and hypertension traits in the Scottish population, by performing several genetic epidemiological analyses. In the first part of this thesis, it aims to study the burden of hypertension in the Scottish population, along with assessing the familial aggregation and heritialbity of BP and hypertension traits. In the second part, it aims to validate the association of common SNPs reported in the large GWAS and to estimate the variance explained by these variants. In this thesis, comprehensive genetic epidemiology analyses were performed on Generation Scotland: Scottish Family Health Study (GS:SFHS), one of the largest population-based family design studies. The availability of clinical, biological samples, self-reported information, and medical records for study participants has allowed several assessments to be performed to evaluate factors that influence BP variation in the Scottish population. Of the 20,753 subjects genotyped in the study, a total of 18,470 individuals (grouped into 7,025 extended families) passed the stringent quality control (QC) criteria and were available for all subsequent analysis. Based on the BP-lowering treatment exposure sources, subjects were further classified into two groups. First, subjects with both a self-reported medications (SRMs) history and electronic-prescription records (EPRs; n =12,347); second, all the subjects with at least one medication history source (n =18,470). In the first group, the analysis showed a good concordance between SRMs and EPRs (kappa =71%), indicating that SRMs can be used as a surrogate to assess the exposure to BP-lowering medication in GS:SFHS participants. Although both sources suffer from some limitations, SRMs can be considered the best available source to estimate the drug exposure history in those without EPRs. The prevalence of hypertension was 40.8% with higher prevalence in men (46.3%) compared to women (35.8%). The prevalence of awareness, treatment and controlled hypertension as defined by the study definition were 25.3%, 31.2%, and 54.3%, respectively. These findings are lower than similar reported studies in other populations, with the exception of controlled hypertension prevalence, which can be considered better than other populations. Odds of hypertension were higher in men, obese or overweight individuals, people with a parental history of hypertension, and those living in the most deprived area of Scotland. On the other hand, deprivation was associated with higher odds of treatment, awareness and controlled hypertension, suggesting that people living in the most deprived area may have been receiving better quality of care, or have higher comorbidity levels requiring greater engagement with doctors. These findings highlight the need for further work to improve hypertension management in Scotland. The family design of GS:SFHS has allowed family-based analysis to be performed to assess the familial aggregation and heritability of BP and hypertension traits. The familial correlation of BP traits ranged from 0.07 to 0.20, and from 0.18 to 0.34 for parent-offspring pairs and sibling pairs, respectively. A higher correlation of BP traits was observed among first-degree relatives than other types of relative pairs. A variance-component model that was adjusted for sex, body mass index (BMI), age, and age-squared was used to estimate heritability of BP traits, which ranged from 24% to 32% with pulse pressure (PP) having the lowest estimates. The genetic correlation between BP traits showed a high correlation between systolic (SBP), diastolic (DBP) and mean arterial pressure (MAP) (G: 81% to 94%), but lower correlations with PP (G: 22% to 78%). The sibling recurrence risk ratio (λS) for hypertension and treatment were calculated as 1.60 and 2.04 respectively. These findings confirm the genetic components of BP traits in GS:SFHS, and justify further work to investigate genetic determinants of BP. Genetic variants reported in the recent large GWAS of BP traits were selected for genotyping in GS:SFHS using a custom designed TaqMan® OpenArray®. The genotyping plate included 44 single nucleotide polymorphisms (SNPs) that have been previously reported to be associated with BP or hypertension at genome-wide significance level. A linear mixed model that is adjusted for age, age-squared, sex, and BMI was used to test for the association between the genetic variants and BP traits. Of the 43 variants that passed the QC, 11 variants showed statistically significant association with at least one BP trait. The phenotypic variance explained by these variant for the four BP traits were 1.4%, 1.5%, 1.6%, and 0.8% for SBP, DBP, MAP, and PP, respectively. The association of genetic risk score (GRS) that were constructed from selected variants has showed a positive association with BP level and hypertension prevalence, with an average effect of one mmHg increase with each 0.80 unit increases in the GRS across the different BP traits. The impact of BP-lowering medication on the genetic association study for BP traits has been established, with typical practice of adding a fixed value (i.e. 15/10 mmHg) to the measured BP values to adjust for BP treatment. Using the subset of participants with the two treatment exposure sources (i.e. SRMs and EPRs), the influence of using either source to justify the addition of fixed values in SNP association signal was analysed. BP phenotypes derived from EPRs were considered the true phenotypes, and those derived from SRMs were considered less accurate, with some phenotypic noise. Comparing SNPs association signals between the four BP traits in the two model derived from the different adjustments showed that MAP was the least impacted by the phenotypic noise. This was suggested by identifying the same overlapped significant SNPs for the two models in the case of MAP, while other BP traits had some discrepancy between the two sources

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Background: Analytical techniques such as methylation-sensitive amplification polymorphism and high-performance liquid chromatography were used to detect variation in DNA methylation of mature Chrysanthemum leaves during the floral transition induced by short-day (SD) treatment. Results: For both early- and late-flowering cultivars, the time from the date of planting to the appearance of the capitulum bud and early blooming were significantly shorter than those of the control. The capitulum development of the early-flowering cultivar was significantly accelerated compared to the control, unlike the late-flowering cultivar. The DNA methylation percentage of leaves was significantly altered during flower development. For the early-flowering cultivar, DNA methylation was 42.2–51.3% before the capitulum bud appeared and 30.5–44.5% after. The respective DNA methylation percentages for the late-flowering cultivar were 43.5–56% and 37.2–44.9%. Conclusions: The DNA methylation percentage of Chrysanthemum leaves decreased significantly during floral development. The decline in DNA methylation was elevated in the early-flowering cultivar compared with the late-flowering cultivar.

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Classical regression analysis can be used to model time series. However, the assumption that model parameters are constant over time is not necessarily adapted to the data. In phytoplankton ecology, the relevance of time-varying parameter values has been shown using a dynamic linear regression model (DLRM). DLRMs, belonging to the class of Bayesian dynamic models, assume the existence of a non-observable time series of model parameters, which are estimated on-line, i.e. after each observation. The aim of this paper was to show how DLRM results could be used to explain variation of a time series of phytoplankton abundance. We applied DLRM to daily concentrations of Dinophysis cf. acuminata, determined in Antifer harbour (French coast of the English Channel), along with physical and chemical covariates (e.g. wind velocity, nutrient concentrations). A single model was built using 1989 and 1990 data, and then applied separately to each year. Equivalent static regression models were investigated for the purpose of comparison. Results showed that most of the Dinophysis cf. acuminata concentration variability was explained by the configuration of the sampling site, the wind regime and tide residual flow. Moreover, the relationships of these factors with the concentration of the microalga varied with time, a fact that could not be detected with static regression. Application of dynamic models to phytoplankton time series, especially in a monitoring context, is discussed.

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International audience

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The EU-funded project UAN - Underwater Acoustic Network aims at conceiving, developing and testing at sea an innovative and operational concept for integrating in a unique communication system submerged, surface and aerial sensors with the objective of protecting off-shore and coastline critical infrastructures. A crucial aspect of the project consisted in the use of autonomous underwater vehicles (AUVs) as mobile nodes in the underwater acoustic communication network. In particular, AUVs have the role of adapting the network geometry to the variation of the acoustic channel. This paper reports on the project concept and vision as well as on the progress of its various development phases. The recent at-sea successes that have been demonstrated within the UAN framework are detailed and results of the final UAN project demonstration, UAN11, held in the May of 2011, are reported. The UAN network was in operation for five continuous days with up to five nodes, of which three of them were mobile nodes. © IFAC.

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We apply wide-field interferometric microscopy techniques to acquire quantitative phase profiles of ventricular cardiomyocytes in vitro during their rapid contraction with high temporal and spatial resolution. The whole-cell phase profiles are analyzed to yield valuable quantitative parameters characterizing the cell dynamics, without the need to decouple thickness from refractive index differences. Our experimental results verify that these new parameters can be used with wide field interferometric microscopy to discriminate the modulation of cardiomyocyte contraction dynamics due to temperature variation. To demonstrate the necessity of the proposed numerical analysis for cardiomyocytes, we present confocal dual-fluorescence-channel microscopy results which show that the rapid motion of the cell organelles during contraction preclude assuming a homogenous refractive index over the entire cell contents, or using multiple-exposure or scanning microscopy.

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Tese de Doutoramento, Gestão da Inovação e do Território, Faculdade de Economia, Universidade do Algarve, 2016

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Understanding the factors that affect seagrass meadows encompassing their entire range of distribution is challenging yet important for their conservation. We model the environmental niche of Cymodocea nodosa using a combination of environmental variables and landscape metrics to examine factors defining its distribution and find suitable habitats for the species. The most relevant environmental variables defining the distribution of C. nodosa were sea surface temperature (SST) and salinity. We found suitable habitats at SST from 5.8 ºC to 26.4 ºC and salinity ranging from 17.5 to 39.3. Optimal values of mean winter wave height ranged between 1.2 m and 1.5 m, while waves higher than 2.5 m seemed to limit the presence of the species. The influence of nutrients and pH, despite having weight on the models, was not so clear in terms of ranges that confine the distribution of the species. Landscape metrics able to capture variation in the coastline enhanced significantly the accuracy of the models, despite the limitations caused by the scale of the study. By contrasting predictive approaches, we defined the variables affecting the distributional areas that seem unsuitable for C. nodosa as well as those suitable habitats not occupied by the species. These findings are encouraging for its use in future studies on climate-related marine range shifts and meadow restoration projects of these fragile ecosystems.

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Dependence of some species on landscape structure has been proved in numerous studies. So far, however, little progress has been made in the integration of landscape metrics in the prediction of species associated with coastal features. Specific landscape metrics were tested as predictors of coastal shape using three coastal features of the Iberian Peninsula (beaches, capes and gulfs) at different scales. We used the landscape metrics in combination with environmental variables to model the niche and find suitable habitats for a seagrass species (Cymodocea nodosa) throughout its entire range of distribution. Landscape metrics able to capture variation in the coastline enhanced significantly the accuracy of the models, despite the limitations caused by the scale of the study. We provided the first global model of the factors that can be shaping the environmental niche and distribution of C. nodosa throughout its range. Sea surface temperature and salinity were the most relevant variables. We identified areas that seem unsuitable for C. nodosa as well as those suitable habitats not occupied by the species. We also present some preliminary results of testing historical biogeographical hypotheses derived from distribution predictions under Last Glacial Maximum conditions and genetic diversity data.

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Background: Recurrent spontaneous abortion is one of the diseases that can lead to physical, psychological, and, economical problems for both individuals and society. Recently a few numbers of genetic polymorphisms in kinase insert domain-containing receptor (KDR) gene are examined that can endanger the life of the fetus in pregnant women. Objective: The risk of KDR gene polymorphisms was investigated in Iranian women with idiopathic recurrent spontaneous abortion (RSA). Materials and Methods: A case controlled study was performed. One hundred idiopathic recurrent spontaneous abortion patients with at least two consecutive pregnancy losses before 20 weeks of gestational age with normal karyotypes were included in the study. Also, 100 healthy women with at least one natural pregnancy were studied as control group. Two functional SNPs located in KDR gene; rs1870377 (Q472H), and rs2305948 (V297I) as well as one tag SNP in the intron region (rs6838752) were genotyped by using PCR based restriction fragment length polymorphism (PCR-RFLP) technique. Haplotype frequency was determined for these three SNPs’ genotypes. Analysis of genetic STRUCTURE and K means clustering were performed to study genetic variation. Results: Functional SNP (rs1870377) was highly linked to tag SNP (rs6838752) (D´ value=0. 214; χ2 = 16.44, p<0. 001). K means clustering showed that k = 8 as the best fit for the optimal number of genetic subgroups in our studied materials. This result was in agreement with Neighbor Joining cluster analysis. Conclusion: In our study, the allele and genotype frequencies were not associated with RSA between patient and control individuals. Inconsistent results in different populations with different allele frequencies among RSA patients and controls may be due to ethnic variation and used sample size.

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Studies indicate that overweight and obesity protect against HIV-disease progression in antiretroviral therapy (ART)-naïve patients. We examined retrospectively the relationship of overweight/obesity with HIV-disease progression in ART-naïve HIV+ adults in Botswana in a case-control study with 18-month follow-up, which included 217 participants, 139 with BMI 18.0-24.9 kg/m 2 and 78 with BMI ≥25 kg/m2. Archived plasma samples were used to determine inflammatory markers: leptin and bacterial endotoxin lipopolysaccharide (LPS), and genotype single nucleotide polymorphisms (SNPs) of the Fat Mass and Obesity Associated Gene (FTO). ^ At baseline, BMI was inversely associated with risk for AIDS-defining conditions (HR=0.218; 95%CI=0.068, 0.701, P=0.011), and higher fat mass was associated with reduced risk of the combined outcome of CD4+cell count ≤250/µL and AIDS-defining conditions, whichever occurred earlier (HR=0.918; 95%CI=0.847, 0.994, P=0.036) over 18 months, adjusting for age, gender, marriage, children, and baseline CD4+cell count and HIV-viral load. ^ FTO-SNP rs17817449 was associated with BMI (OR=1.082; 95%CI=1.001, 1.169; P=0.047). Fat mass was associated with the risk alleles of rs1121980 (OR=1.065; 95%CI=1.009, 1.125, P=0.021), rs8050136 (OR=1.078; 95%CI=1.021, 1.140; P=0.007), and rs17817449 (OR=1.086; 95%CI=1.031, 1.145; P=0.002), controlling for age, gender, tribe, total energy intake, and activity. There were no associations of SNPs with markers of disease progression. ^ Leptin levels were positively associated with BMI (β=1.764; 95%CI=0.788, 2.739; P=0.022) and fat mass (β=0.112; 95%CI=0.090, 0.135; P<0.001), but inversely with viral load (β=-0.305; 95%CI=-0.579, -.031; P=0.030). LPS levels were inversely associated with BMI (OR=0.790, 95%CI=0.630, 0.990; P=0.041), and fat mass (OR=0.852, 95%CI=0.757, 0.958; P=0.007) and directly with viral load (OR=2.608, 95%CI=1.111, 6.124; P=0.028), adjusting for age, gender, smoking and %fat mass. ^ In this cohort, overweight/obesity predicted slower HIV-disease progression. Obesity may confer an advantage in maintaining fat stores to support the overactive immune system. FTO-SNPs may contribute to the variation in fat mass; however, they were not associated with HIV-disease progression. Our findings suggest that the obesity paradox may be explained by the association of increased LPS with lower BMI and higher viral load; while viral load decreased with increasing leptin levels. Studies in African populations are needed to clarify whether genetic variation and inflammation mediate the obesity paradox in HIV-disease progression.^

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Skeletal maturity is used to evaluate biological maturity status. Information about the association between socio-economic status (SES) and skeletal maturity is limited in Portugal. Aims: The aim of this study is to document the skeletal maturity of youths in Madeira and to evaluate variation in maturity associated with SES. Subjects and methods: The study involved 507 subjects (256 boys and 251 girls) from the Madeira Growth Study, a mixed-longitudinal study of five cohorts (8, 10, 12, 14 and 16 years of age) followed at yearly intervals over 3 years (1996–1998). A total of 1493 observations were made. Skeletal age was estimated from radiographs of the hand and wrist using the Tanner–Whitehouse 2 method (TW2). Social class rankings were based on Graffar’s (1956) method. Five social rankings were subsequently grouped into three SES categories: high, average and low. Results: Median for the radius, ulna and short finger bones (RUS scores) in the total sample of boys and girls increased curvilinearly across age whereas median for the 7 (without pisiform) carpal bones (Carpal scores) increased almost linearly. The 20-bone maturity scores demonstrated distinctive trends by gender: the medians for boys increased almost linearly while the medians for girls increased curvilinearly. SES differences were minimal. Only among children aged 10–11 years were high SES boys and girls advanced in skeletal maturity. Madeira adolescents were advanced in skeletal maturity compared with Belgian reference values. Conclusion: The data suggests population variation in TW2 estimates of skeletal maturation. Skeletal maturity was not related to SES in youths from Madeira.