Avaliação da aderência pneu-pavimento para diferentes tipos de pavimentos utilizando o International Friction Index (IFI)

A condição superficial do pavimento é um fator importante para a avaliação da segurança viária por caracterizar diretamente os níveis de atrito, que condicionam as frenagens veiculares. No intuito de padronizar os diversos indicadores de aderência, desenvolveu-se o International Friction Index (IFI). O principal objetivo deste método é quantificar o atrito superficial, reportando-o como um índice em escala que possa ser utilizado internacionalmente. Neste contexto, o presente estudo tem como objetivo avaliar a aderência pneu-pavimento para diferentes tipos de pavimentos utilizados no Brasil. Para isso, consolidou-se um extenso banco de dados, obtidos a partir da revisão da literatura, de microtextura e de macrotextura, englobando aproximadamente dez técnicas diferentes de pavimentação. Desta análise, obtiveram-se curvas que correlacionam coeficiente de atrito e a velocidade, observando-se a preponderância da macrotextura do material no desempenho da aderência pneu-pavimento.Pavement’s surface condition is a key parameter to evaluate traffic safety because it directly characterizes friction levels, related to the quality of vehicular braking. Defined by both micro- and macrotexture, different techniques applied to determine skid resistance are documented in the literature. In order to standardized skid resistance, International Friction Index (IFI) was developed. Its main goal is to quantify frictional coefficient, reporting it as a single-scale indicator, which can be assessed worldwide. In this context, this paper’s mean objective is to assess skid resistance for different paving techniques. For that, an extent database of micro- and macrotexture was collected from the literature, counting on more than 10 different paving techniques. From this analysis, curves of frictional coefficient versus speed were plotted, observing macrotexture’s preponderance on skid resistance performance.info:eu-repo/semantics/publishedVersio

Enzymatic time-temperature integrator device for chromatic quality check of Cova da Beira’s cherry (Portugal)

Cherry is a fruit widely appreciated by consumers in general. In Portugal, within the Beira Interior region, and particularly, Cova da Beira, is the most representative area with a production of more than 50% of the national production. The peculiar characteristics of cherries, such as color, firmness, palate, among others, increase the demand for this fruit, which can only be commercialized during a short period. Its high perishability interferes with the shelf life and consequently generates undesirable changes in the cherry flow chain. In order to ensure food quality and safety and prevent food waste, a time-temperature integrator (TTI) device to monitor the quality of the cherry in real time is proposed. This device suffers a chromatic change with the temperature variation over time. For the specific case of the cherry, the kinetic parameters for thermal inactivation are determined which leads to the proposal of an enzymatic-type TTI, where the degradation of the phenolic compounds occurs, which are substrates of the polyphenol oxidase enzyme, whose hydroxylation reaction of a monophenol in o-diphenol leads to the oxidation in o-Quinone. This device aims to help retailers to decide when and where to sell the food items taking into account the remaining shelf life, as well as support the decision of purchase by the consumer predicting through a chromatic and expedite stamp the food quality and safetyinfo:eu-repo/semantics/publishedVersio

Out-of-phase oscillation between superfluid and thermal components for a trapped Bose condensate under oscillatory excitation

The vortex nucleation and the emergence of quantum turbulence induced by oscillating magnetic fields, introduced by Henn E A L, et al. 2009 (Phys. Rev. A 79, 043619) and Henn E A L, et al. 2009 (Phys. Rev. Lett. 103, 045301), left a few open questions concerning the basic mechanisms causing those interesting phenomena. Here, we report the experimental observation of the slosh dynamics of a magnetically trapped $^{87}$Rb Bose-Einstein condensate (BEC) under the influence of a time-varying magnetic field. We observed a clear relative displacement in between the condensed and the thermal fraction center-of-mass. We have identified this relative counter move as an out-of-phase oscillation mode, which is able to produce ripples on the condensed/thermal fractions interface. The out-of-phase mode can be included as a possible mechanism involved in the vortex nucleation and further evolution when excited by time dependent magnetic fields.Comment: 5 pages, 5 figures, 25 reference

The non-coding snRNA 7SK controls transcriptional termination, poising, and bidirectionality in embryonic stem cells

BACKGROUND: Pluripotency is characterized by a unique transcriptional state, in which lineage-specification genes are poised for transcription upon exposure to appropriate stimuli, via a bivalency mechanism involving the simultaneous presence of activating and repressive methylation marks at promoter-associated histones. Recent evidence suggests that other mechanisms, such as RNA polymerase II pausing, might be operational in this process, but their regulation remains poorly understood. RESULTS: Here we identify the non-coding snRNA 7SK as a multifaceted regulator of transcription in embryonic stem cells. We find that 7SK represses a specific cohort of transcriptionally poised genes with bivalent or activating chromatin marks in these cells, suggesting a novel poising mechanism independent of Polycomb activity. Genome-wide analysis shows that 7SK also prevents transcription downstream of polyadenylation sites at several active genes, indicating that 7SK is required for normal transcriptional termination or control of 3′-UTR length. In addition, 7SK suppresses divergent upstream antisense transcription at more than 2,600 loci, including many that encode divergent long non-coding RNAs, a finding that implicates the 7SK snRNA in the control of transcriptional bidirectionality. CONCLUSIONS: Our study indicates that a single non-coding RNA, the snRNA 7SK, is a gatekeeper of transcriptional termination and bidirectional transcription in embryonic stem cells and mediates transcriptional poising through a mechanism independent of chromatin bivalency.GCB was funded by an EMBO Long-Term Post-Doctoral Fellowship and a Marie Curie Intra-European Fellowship for Career Development. PA was supported by a Royal Society Newton International Fellowship and a Corpus Christi College research fellowship. This work was supported by Cancer Research UK, European Research Council (Advanced Grant, TK), EMBL (PB) and Swedish Research Council (GCB)

Design and Implementation of a Collaborative Clinical Practice and Research Documentation System Using SNOMED-CT and HL7-CDA in the Context of a Pediatric Neurodevelopmental Unit

This paper introduces a prototype for clinical research documentation using the structured information model HL7 CDA and clinical terminology (SNOMED CT). The proposed solution was integrated with the current electronic health record system (EHR-S) and aimed to implement interoperability and structure information, and to create a collaborative platform between clinical and research teams. The framework also aims to overcome the limitations imposed by classical documentation strategies in real-time healthcare encounters that may require fast access to complex information. The solution was developed in the pediatric hospital (HP) of the University Hospital Center of Coimbra (CHUC), a national reference for neurodevelopmental disorders, particularly for autism spectrum disorder (ASD), which is very demanding in terms of longitudinal and cross-sectional data throughput. The platform uses a three-layer approach to reduce components’ dependencies and facilitate maintenance, scalability, and security. The system was validated in a real-life context of the neurodevelopmental and autism unit (UNDA) in the HP and assessed based on the functionalities model of EHR-S (EHR-S FM) regarding their successful implementation and comparison with state-of-the-art alternative platforms. A global approach to the clinical history of neurodevelopmental disorders was worked out, providing transparent healthcare data coding and structuring while preserving information quality. Thus, the platform enabled the development of user-defined structured templates and the creation of structured documents with standardized clinical terminology that can be used in many healthcare contexts. Moreover, storing structured data associated with healthcare encounters supports a longitudinal view of the patient’s healthcare data and health status over time, which is critical in routine and pediatric research contexts. Additionally, it enables queries on population statistics that are key to supporting the definition of local and global policies, whose importance was recently emphasized by the COVID pandemic.info:eu-repo/semantics/publishedVersio

Agricultura apoiada pela comunidade: poderia a experiência dos agricultores americanos ser útil para os agricultores urbanos brasileiros?

O objetivo deste trabalho foi obter algumas informações sobre o projeto Agricultura Apoiada pela Comunidade (AAC) nos EUA e avaliar se consumidores e produtores urbanos pobres de uma cidade brasileira de baixa renda aceitariam se engaja neste tipo de projeto

Extraction, selection and comparison of features for an effective automated computer-aided diagnosis of Parkinson's disease based on [123I]FP-CIT SPECT images

Purpose This work aimed to assess the potential of a set of features extracted from [I-123] FP-CIT SPECT brain images to be used in the computer-aided "in vivo" confirmation of dopaminergic degeneration and therefore to assist clinical decision to diagnose Parkinson's disease.Methods Seven features were computed from each brain hemisphere: five standard features related to uptake ratios on the striatum and two features related to the estimated volume and length of the striatal region with normal uptake. The features were tested on a dataset of 652 [I-123] FP-CIT SPECT brain images from the Parkinson's Progression Markers Initiative. The discrimination capacities of each feature individually and groups of features were assessed using three different machine learning techniques: support vector machines (SVM), k-nearest neighbors and logistic regression.Results Cross-validation results based on SVM have shown that, individually, the features that generated the highest accuracies were the length of the striatal region (96.5%), the putaminal binding potential (95.4%) and the striatal binding potential (93.9%) with no statistically significant differences among them. The highest classification accuracy was obtained using all features simultaneously (accuracy 97.9%, sensitivity 98% and specificity 97.6%). Generally, slightly better results were obtained using the SVM with no statistically significant difference to the other classifiers for most of the features.Conclusions The length of the striatal region uptake is clinically useful and highly valuable to confirm dopaminergic degeneration "in vivo" as an aid to the diagnosis of Parkinson's disease. It compares fairly well to the standard uptake ratio-based features, reaching, at least, similar accuracies and is easier to obtain automatically. Thus, we propose its day to day clinical use, jointly with the uptake ratio-based features, in the computer-aided diagnosis of dopaminergic degeneration in Parkinson's disease

The neural basis of fatigue in multiple sclerosis: A multimodal MRI approach

BACKGROUND: Fatigue is a frequent disabling symptom in multiple sclerosis (MS), but its pathophysiology remains incompletely understood. This study aimed to explore the underlying neural basis of fatigue in patients with MS. METHODS: We enrolled 60 consecutive patients with MS and 60 healthy controls (HC) matched on age, sex, and education. Fatigue was assessed using the Portuguese version of the Modified Fatigue Impact Scale (MFIS). All participants underwent 3T brain MRI (conventional and diffusion tensor imaging [DTI] sequences). White matter (WM) focal lesions were identified and T1/T2 lesion volumes were computed. Tract-based spatial statistics were applied for voxel-wise analysis of DTI metrics fractional anisotropy and mean diffusivity (MD) on normal-appearing WM (NAWM). Using Freesurfer software, total and regional volumes of cortical and subcortical gray matter (GM) were calculated. RESULTS: Compared to HC, patients with MS scored significantly higher on MFIS (33.8 ± 19.7 vs 16.5 ± 15.1, p < 0.001). MFIS scores were not significantly correlated with T1/T2 lesion volumes, total GM volume, or any regional volume of cortical and subcortical GM. Significant correlations were found between global scores of MFIS and MD increase of the NAWM skeleton, including corona radiata, internal capsule, external capsule, corticospinal tract, cingulum, corpus callosum, fornix, superior longitudinal fasciculus, superior fronto-occipital fasciculus, sagittal stratum, posterior thalamic radiation, cerebral peduncle, and uncinate fasciculus. CONCLUSIONS: In this study, fatigue was associated with widespread NAWM damage but not with lesion load or GM atrophy. Functional disconnection, caused by diffuse microstructural WM damage, might be the main neural basis of fatigue in MS.info:eu-repo/semantics/publishedVersio