89 research outputs found
Monitoring feet temperature using thermography
Studies show that regular monitoring of feet temperature may limit the incidence of disabling conditions such as foot ulcers and lower-limb amputations. Infrared thermometry and liquid crystal thermography were identified as the leading technologies in use today. In this study, we analysed the maximum temperature and tested some mathematical models for the foot temperature distribution
Mathematical model of feet temperature
In this work it is consider the problem of finding the best approximation to characterize the feet temperature
distribution. For this study it was consider the nonlinear least squares technique, combined with penalty method, to identify
the function that approximate better the data obtained through thermographic images. The preliminary results indicate that the
best function approximation is based on trigonometric sums
Monitoring feet temperature using thermography
Studies show that regular monitoring of feet temperature may limit the incidence of disabling conditions such as foot ulcers and lower-limb amputations. Infrared thermometry and liquid crystal thermography were identified as the leading technologies in use today. In this study, we analysed the maximum temperature and tested some mathematical models for the foot temperature distribution
Cell-free layer (CFL) analysis in a glass capillary: comparison between a manual and automatic method
In this study, in vitro blood flowing through a 100 m glass capillary was studied. The images were captured
using a confocal system and post-processed using Image J and MatLab. The aim of the present work, was to measure the
trajectories of the cell-free layer (CFL) by using two different methods, i. e., a manual method (MM) and an automatic method (AM). For theMM we have used amanual tracking plugin (MTrackJ) from Image J to track labeled red blood cells (RBCs) flowing around the boundary of the RBCs core. For the AM we have used a MatLab scripts to measure automatically the CFL trajectories. The preliminary numerical results suggest that the CFL trajectories follow a
polynomial function for both methods.The authors acknowledge the financial support provided by: PTDC/SAU-BEB/108728/2008, PTDC/SAU-BEB/105650/2008, PTDC/EME-MFE/099109/2008 and PTDC/SAU-ENB/116929/2010 from the FCT (Science and Technology Foundation) and COMPETE, Portugal
Cell-free layer measurements in bifurcating microchannels: a global approach
In the present work, in vitro blood flowing through bifurcating microchannels was studied, with the aim of characterizing the cell-free layer (CFL). The original images were obtained by means of a high-speed video microscopy system and then processed in MatLab using the Image Processing
Toolbox. The numerical data was obtained automatically and analyzed by optimization techniques using the genetic algorithm approach. The results suggest that the CFL were formed in a similar way at the upper and lower regions in all bifurcations, and the measurements can be approximated
through a sum of trigonometric functions
Impacts of State Reopening Policy on Human Mobility
This study quantifies the effect of state reopening policies on daily mobility, travel, and mixing behavior during the COVID-19 pandemic. We harness cell device signal data to examine the effects of the timing and pace of reopening plans in different states. We quantify the increase in mobility patterns during the reopening phase by a broad range of cell-device-based metrics. Soon (four days) after reopening, we observe a 6% to 8% mobility increase. In addition, we find that temperature and precipitation are strongly associated with increased mobility across counties. The mobility measures that reflect visits to a greater variety of locations responds the most to reopening policies, while total time in vs. outside the house remains unchanged. The largest increases in mobility occur in states that were late adopters of closure measures, suggesting that closure policies may have represented more of a binding constraint in those states. Together, these four observations provide an assessment of the extent to which people in the U.S. are resuming movement and physical proximity as the COVID-19 pandemic continues
Multiple pathways mediate the effects of climate change on maternal reproductive traits in a red deer population
Temporal changes in phenological traits arising as a consequence of recent rapid environmental change have been widely demonstrated in animal populations. Increasingly, studies are seeking to understand the impact of changes in such traits on individual fitness and population dynamics, with the ultimate aim of predicting population persistence or extinction under different climate scenarios. Here, we examined the effects of environmental change on maternal reproductive traits in a wild population of red deer (Cervus elaphus) and sought to explain why, despite a rapid advance in offspring birth dates, we observed no apparent consequences for offspring fitness. By using path analysis, we identified both direct and indirect paths along which changes in environmental conditions affected birth date, birth mass, juvenile survival, and female fecundity. In general, warmer temperatures were associated with earlier birth dates and greater birth mass, and higher rainfall was associated with reduced juvenile survival and reduced female fecundity. We also examined concurrent effects of population density, maternal age, and reproductive history, and found that temporal stasis in average trait values, at least in part, could be explained by antagonistic roles of direct and indirect effects of changing climate and increasing population density. Identification of the many mechanisms that contribute to the dynamics of phenotypic traits is challenging; this study demonstrates the need to consider both climatic and demographic variation in order to understand the fitness consequences of changes in phenological traits
Blood flow of bubbles moving in microchannels with bifurcations
The gas embolism is a well-known phenomenon. Previous studies
have been performed to understand the formation, the behavior and the influence
of air bubbles in microcirculation. This study aims to investigate the flow of
bubbles in a microchannel network with bifurcations. For that purpose, a
microchannel network was fabricated by soft lithography. The working fluids
used were composed by sheep red blood cells (RBCs) suspended in dextran 40
and two different hematocrits were studied, 5% and 10%. The in vitro blood
flow was analyzed for a flow rate of lO ~-tllmin, by using an inverted microscope
and a high-speed camera. It was possible to visualize the formation of the
bubbles and their behavior along the network. The results show that the passage
of air bubbles influences the cells local concentration, since a higher concentration
of cells was seen upstream to the bubble and lower concentrations
downstream to the bubble.This work was supported by Fundação para a Ciência e a Tecnologia
(FCT), Portugal, under the strategic grants UID/EMS/04077/2019, UID/EEA/04436/2019 and
UID/EMS/00532/2019. The authors are also grateful for the partial funding of FCT through the
projects POCI-01-0145-FEDER-016861 (ref: PTDC/QEQ-FIT/4287/2014), NORTE-01-0145-
FEDER-029394, NORTE-01-0145-FEDER-030171, funded by COMPETE2020, NOR1E2020,
PORTUGAL2020, and FEDER. D. Bento acknowledges the PhD scholarship SFRH/BD/911921
2012 granted by FCT.info:eu-repo/semantics/publishedVersio
Antioxidant activity of sugar molasses, including protective effect against DNA oxidative damage
Extracts were obtained from molasses, a byproduct of the sugar industry, via a number of chromatographic steps. Their antioxidant capacity was studied, including the inhibitory effect upon DNA oxidative damage;the phenolic compound profile there of was ascertained as well. Two extracts exhibited significant antioxidant features,
expressed by their capacity to decolorize ABTS radical cation and to scavenge hydroxyl free radicals (via deoxyribose
assay). Those 2 extracts also brought about protection against induced DNA oxidative damage (via decreasing DNA scission, as assessed by electrophoresis).The phenolic compounds syringic acid,p-hydroxybenzoic acid, vanillic acid, p-hydroxybenzaldehyde, and ferulic acid were positively identified and quantified
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