302 research outputs found
Sintra vegetation and landscape
The field trip to Sintra region, as part
of the 48th IAVS Symposium, aims to
illustrate well-preserved and
representative plant communities of
Sintra municipality. It consists of two
short field stops and a 3 km wal
Recommended from our members
airborne.cam: a risk calculator of SARS-CoV-2 aerosol transmission under well-mixed ventilation conditions
http://airborne.cam helps users understand how their surroundings and day-to-day behaviour can be adapted in order to minimise the risk of indoors transmission of the SARS-CoV-2 virus. The app is based on the well-mixed approach to calculate the individual risk of infection based on the exposure time of a healthy, susceptible individual to infectious long-suspended viral particles indoors. This approach considers that individuals are far apart from each other, that is, there is no risk of short-range transmission either by large or small droplets/aerosols, nor by contact with contaminated surfaces. The basic user can change inputs such as ventilation rate, type of face covering, number of occupants, and type of activity to assess their impact on risk of infection, while more advanced features are available for the user familiar with science concerning aerosol transmission
Identification of genomic loci associated with genotypic and phenotypic variation among Pseudomonas aeruginosa clinical isolates from pneumonia
In this work, a genotype-phenotype survey of a highly diversified Pseudomonas aeruginosa collection was conducted, aiming to detail pathogen-associated scenarios that clinicians face nowadays. Genetic relation based on RAPD-PCR of 705 isolates, retrieved from 424 patients and several clinical contexts, reported an almost isolate-specific molecular-pattern. Pneumonia-associated isolates HB13 and HB15, clustered in the same RAPD-PCR group, were selected to evaluate the genomic background underlying their contrasting antibiotic resistance and virulence. The HB13 genome harbors antibiotic-inactivating enzymes-coding genes (e.g. aac(3)-Ia, arr, blaVIM-2) and single-nucleotide variations (SNVs) in antibiotic targets, likely accounting for its pan-resistance, whereas HB15 susceptibility correlated to predicted dysfunctional alleles. Isolate HB13 showed the unprecedented rhl-cluster absence and variations in other pathogen competitiveness contributors. Conversely, HB15 genome comprises exoenzyme-coding genes and SNVs linked to increased virulence. Secretome analysis identified signatures features with unknown function as potential novel pathogenic (e.g. a MATE-protein in HB13, a protease in HB15) and antibiotic resistance (a HlyD-like secretion protein in HB13) determinants. Detection of active prophages, proteases (including protease IV and alkaline metalloproteinase), a porin and a peptidase in HB15 highlights the secreted arsenal likely essential for its virulent behavior. The presented phenotype-genome association will contribute to the current knowledge on Pseudomonas aeruginosa pathogenomics.This work was supported by the strategic programme UID/BIA/0050/2013 (POCI-01-0145-FEDER-007569) funded by national funds through FCT I.P., by ERDF through the COMPETE2020 - Programa Operacional Competitividade e Internacionalização (POCI) and through a PhD grant (SFRH/BD/98558/2013) attributed to C.S.M. The facility for Biological Mass Spectrometry Isabel Moura was funded by Proteomass Scientific Society. H.M.S. is funded by the FCT 2015 Investigator Program (IF/00007/2015)
Peaches Detection Using a Deep Learning Technique - A Contribution to Yield Estimation, Resources Management, and Circular Economy
Fruit detection is crucial for yield estimation and fruit picking system performance. Many
state-of-the-art methods for fruit detection use convolutional neural networks (CNNs). This paper
presents the results for peach detection by applying a faster R-CNN framework in images captured
from an outdoor orchard. Although this method has been used in other studies to detect fruits, there
is no research on peaches. Since the fruit colors, sizes, shapes, tree branches, fruit bunches, and
distributions in trees are particular, the development of a fruit detection procedure is specific. The
results show great potential in using this method to detect this type of fruit. A detection accuracy of
0.90 using the metric average precision (AP) was achieved for fruit detection. Precision agriculture
applications, such as deep neural networks (DNNs), as proposed in this paper, can help to mitigate
climate change, due to horticultural activities by accurate product prediction, leading to improved
resource management (e.g., irrigation water, nutrients, herbicides, pesticides), and helping to reduce
food loss and waste via improved agricultural activity scheduling.The authors are thankful to Fundação para a Ciência e Tecnologia (FCT) and
R&D Unit “Center for Mechanical and Aerospace Science and Technologies” (C-MAST), under
project UIDB/00151/2020, for the opportunity and the financial support to carry on this project. The
contributions of Hugo Proença and Pedro Inácio in this work were supported by FCT/MEC through
FEDER—PT2020 Partnership Agreement under Project UIDB//50008/2021.info:eu-repo/semantics/publishedVersio
Estimates of the stochasticity of droplet dispersion by a cough.
In this paper, the statistical distributions of the position and the size of the evaporating droplets after a cough are evaluated, thus characterizing the inherent stochasticity of respiratory releases due to turbulence. For that, ten independent realizations of a cough with realistic initial conditions and in a room at 20 °C and 40% relative humidity were performed with large eddy simulations and Lagrangian tracking of the liquid phase. It was found that although turbulence decreases far from the emitter, it results in large variations in the spatial distribution of the droplets. The total suspended liquid mass after 60 s from the cough is in good agreement with that estimated by a one-dimensional model accounting for settling and evaporation under quiescent conditions, while deposition times of droplets in the 10-100 μm range are found to vary significantly, reflected in the mass of liquid, and hence the virus content, potentially inhaled by a receptor. The high variability between events is due to the local fluctuations of temperature, humidity, and velocity on droplet evaporation and motion. The droplet distribution suggests that, in the absence of face coverings, an unprotected cough is not safe at 2 m away from the emitter even outdoors. The results indicate that mitigation measures, such as ventilation to address long-range transmission, can be based on the total suspended liquid content evaluated from reduced-order models. However, the large variability of viral content in the near field produces wide variations in estimates of risk; therefore, a stochastic approach is needed for evaluating short-range transmission risk
Bridging the Gap between Preclinical and Clinical Microbicide Trials: Blind Evaluation of Candidate Gels in Murine Models of Efficacy and Safety
Despite significant protection in preclinical studies, cellulose sulfate (CS) failed to protect women against HIV-1/2 and was associated with a trend toward increased HIV-1 acquisition in one of the clinical trials. These results highlight the need for preclinical tests more predictive of clinical outcomes. The objective of this study was to test coded vaginal gels, including CS, in murine models of safety and efficacy to determine the models' utility for evaluating future products.Four coded formulations, including 6% CS, 2% PRO 2000 and two placebo gels, were administered intravaginally to medroxyprogesterone-treated mice and their ability to prevent genital herpes (efficacy) or to alter the susceptibility to low dose HSV challenge (safety) was determined. Nonoyxnol-9 served as a positive toxicity control.CS and PRO 2000 significantly protected mice from genital herpes following infection with a laboratory or clinical isolate of HSV-2 introduced in buffer (p<0.001). However, protection was reduced when virus was introduced in seminal plasma. Moreover, mice were significantly more susceptible to infection with low doses of HSV-2 when challenged 12 h after the 7th daily dose of CS or nonoxynol-9 (p<0.05). The increased susceptibility was associated with alterations in epithelial architecture.CS prevented genital herpes when present at the time of viral challenge, but increased the rate of infection when gel was applied daily for 7 days with a vaginal wash prior to viral inoculation. The findings presumably reflect altered epithelial architecture, which may have contributed to the trend towards increased HIV observed clinically
Antimicrobial activity of a 3D-printed polymethylmethacrylate dental resin enhanced with graphene
The present study aimed to test, in vitro, the antimicrobial activity against Candida albicans and Streptococcus mutans and the surface roughness of a 3D-printed polymethylmethacrylate dental resin enhanced with graphene. A 3D-printed polymethylmethacrylate dental resin was reinforced with four different concentrations of graphene: 0.01, 0.1, 0.25 and 0.5 wt%. Neat resin was used as a control. The specimens were printed in a liquid crystal display printer. Disc specimens were used in antimicrobial evaluation, and bar-shaped specimens were used to measure surface roughness. The study of antimicrobial activity included the inhibition of the growth of C. albicans and S. mutans and their adhesion to the resin’s surface. Surface roughness increased with the increase in the graphene concentration. The growth inhibition of C. albicans was observed in the different concentrations of graphene after 24 h, with no recovery after 48 h. The specimens doped with graphene were capable of inactivating S. mutans after 48 h. The surface-adhesion studies showed that the density of microbial biofilms decreases in the case of specimens doped with graphene. Graphene, despite increasing the resin’s surface roughness, was effective in inhibiting the growth and the adhesion to the resin’s surface of the main inducers of prosthetic stomatitis.info:eu-repo/semantics/publishedVersio
How players exploit variability and regularity of game actions in female volleyball teams
Variability analysis has been used to understand how competitive constraints shape different behaviours in team sports. In this study, we analysed and compared variability of tactical performance indices in players within complex I at two different competitive levels in volleyball. We also examined whether variability was influenced by set type and period. Eight matches from the 2012 Olympics competition and from the Portuguese national league in the 2014–2015 season were analysed (1496 rallies). Variability of setting conditions, attack zone, attack tempo and block opposition was assessed using Shannon entropy measures. Magnitude-based inferences were used to analyse the practical significance of compared values of selected variables. Results showed differences between elite and national teams for all variables, which were co-adapted to the competitive constraints of set type and set periods. Elite teams exploited system stability in setting conditions and block opposition, but greater unpredictability in zone and tempo of attack. These findings suggest that uncertainty in attacking actions was a key factor that could only be achieved with greater performance stability in other game actions. Data suggested how coaches could help setters develop the capacity to play at faster tempos, diversifying attack zones, especially at critical moments in competition
Is obesity a risk factor for carotid atherosclerotic disease?—opportunistic review
Obesity is a risk factor for coronary atherosclerosis. However, the influence of adipose tissue in carotid atherosclerosis is not completely understood. No systematic review/meta-analysis was previously performed to understand if obesity is a risk factor for carotid atherosclerosis. This paper aims to provide an opportunistic review of the association between obesity and carotid atherosclerosis and define the role of the different adipose tissue depots in the characteristics of carotid stenosis. The databases PubMed and Cochrane Library were searched on 15–27 April and 19 May 2021. A total of 1750 articles published between 1985 and 2019 were identified, 64 were preselected, and 38 papers (35,339 subjects) were included in the final review. The most frequent methods used to determine obesity were anthropometric measures. Carotid plaque was mostly characterized by ultrasound. Overall obesity and visceral fat were not associated with the presence of carotid plaque when evaluated separately. Waist-hip ratio, however, was a significant anthropometric measure associated with the prevalence of carotid plaques. As it reflected the ratio of visceral and subcutaneous adipose tissue, the balance between these depots could impact the prevalence of carotid plaques.This work was supported by the Portuguese Society of Vascular Surgery. This work was developed under the scope of project NORTE-01-0145-FEDER- 000013, supported by the Northern Portugal Regional Operational Programme (NORTE 2020) under the Portugal Partnership Agreement, through the European Regional Development Fund (FEDER), and by National funds, through the Foundation for Science and Technology (FCT)—project UIDB/50026/2020 and UIDP/50026/2020
Comparison between experimental data and numerical modeling for the natural circulation phenomenon
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