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Beyond excitation/inhibition imbalance in multidimensional models of neural circuit changes in brain disorders
A leading theory holds that neurodevelopmental brain disorders arise from imbalances in excitatory and inhibitory (E/I) brain circuitry. However, it is unclear whether this one-dimensional model is rich enough to capture the multiple neural circuit alterations underlying brain disorders. Here, we combined computational simulations with analysis of in vivo two-photon Ca2+ imaging data from somatosensory cortex of Fmr1 knock-out (KO) mice, a model of Fragile-X Syndrome, to test the E/I imbalance theory. We found that: (1) The E/I imbalance model cannot account for joint alterations in the observed neural firing rates and correlations; (2) Neural circuit function is vastly more sensitive to changes in some cellular components over others; (3) The direction of circuit alterations in Fmr1 KO mice changes across development. These findings suggest that the basic E/I imbalance model should be updated to higher dimensional models that can better capture the multidimensional computational functions of neural circuits
Design of a learning environment for embedded system
Embedded systems have an everyday presence and direct impact in our lives. Therefore, Universities are
continuously improving their courses in microprocessor and embedded programming. Although the diversity of
curriculums, the availability of learning tools, where the student can practice and improve their skills, is a key factor to the success of the learning process. The platform developed and presented in this paper results from author’s experience in teaching embedded systems. From the analysis of teaching/learning needs, a learning environment based on the MSP430 family was designed. This tool can be expanded by modules and adjusted, at a specific time, to student's real needs. All modules can be interconnected by an I2C bus, allowing to expand the capabilities of the platform. The developed modules allow the practice of subjects related with digital IO, analog interface, user interface, wireless communications, and energy management and conservation.info:eu-repo/semantics/publishedVersio
VALIDATION WITH VIDEOMETRY OF AN INTEGRATED SYSTEM TO ASSESS HORIZONTAL INTRA-CYCLIC VELOCITY WITH A MECHANICAL SPEED-METER
The aim of this paper was to: validate an integrated system (i.e., software application and hardware after calibration) to assess human‟s horizontal intra-cyclic velocity with a mechanical speedo-meter. System validation was done for a set of land-based human locomotion techniques (from slow walk to maximal running) in four subjects and comparing it with a videometric system (i.e. APAS). There were no significant differences between pair wise data (speedo-meter versus APAS data) using student„s t-test for both velocity coefficient of variation and maximal velocity. Linear regression models were very high for both the velocity coefficient of variation and maximal velocity. More than 80% of the Bland-Altman plots were within 1.96 standard-deviations
so much work, so many lost opportunities
Mainoli, B., Machado, T., Duarte, G. S., Prada, L., Gonçalves, N., Ferreira, J. J., & Costa, J. (2021). Analysis of clinical and methodological characteristics of early COVID-19 treatment clinical trials: so much work, so many lost opportunities. BMC Medical Research Methodology, 21(1), 1-10. [42]. https://doi.org/10.1186/s12874-021-01233-wBackground: The COVID-19 pandemic continues to rage on, and clinical research has been promoted worldwide. We aimed to assess the clinical and methodological characteristics of treatment clinical trials that have been set forth as an early response to the COVID-19 pandemic. Methods: First, we reviewed all registered clinical trials on COVID-19. The World Health Organization International Trials Registry Platform and national trial registries were searched for COVID-19 trials through April 19th, 2020. For each record, independent researchers extracted interventions, participants, and methodological characteristics. Second, on September 14th, 2020 we evaluated the recruitment status and availability of the results of COVID-19 treatment trials previously identified. Results: In April 2020, a total of 580 trials evaluating COVID-19 treatment were registered. Reporting quality was poor (core participant information was missing in 24.1 to 92.7%). Between 54.0 and 93.8% of the trials did not plan to include older people or those with a higher baseline risk. Most studies were randomised (67.9%), single-centre (58.3%), non-industry-funded (81.1%), to be conducted in China (47.6%), with a median duration of 184 days and a median sample size of 100 participants. Core endpoints (mortality, clinical status, and hospitalization length) were planned to be assessed in 5.2 to 13.1% of the trials. Five months later, 66 trials (11.4%) were reported as “Completed”, and only 46 (7.9%) had public results available. One hundred forty-four of 580 trials (24.8%) either had the status “Not yet recruiting” or “Suspended”, and 18 (3.1%) trials were prematurely stopped (“Terminated” or “Withdrawn”) The number of completed trials and trials with results are much lower than anticipated, considering the planned follow-up. Conclusions: Our results raise concerns about the success of the initial global research effort on COVID-19 treatment. The clinical and methodological characteristics of early COVID-19 treatment trials limit their capability to produce clear answers to critical questions in the shortest possible time.publishersversionpublishe
An experimental investigation on nano-TiO2 and fly ash based high performance concrete
High performance concrete (HPC) offers several advantages over normal-strength concrete, namely, high mechanical strength
and high durability. Therefore, HPC allows for concrete structures with less steel reinforcement and a longer service life,
both of which are crucial issues in the eco-efficiency of construction materials. Nevertheless international publications on
the field of concrete containing nanoparticles are scarce when compared to Portland cement concrete (around 1%) of the
total international publications. HPC nanoparticle-based publications are even scarcer. This article presents the results of
an experimental investigation on the mechanical properties and durability of HPC based on nano-TiO2 and fly ash. The
durability performance was assessed by means of water absorption by immersion, water absorption by capillarity, ultrasonic
pulse velocity, electric resistivity, chloride diffusion and resistance to sulphuric acid attack. The results show that the concretes
containing an increased content of nano-TiO2 show decreased durability performance. The results also show that concrete
with 1% nano-TiO2 and 30% fly ash as Portland cement replacement show a high mechanical strength (C55/C67) and a high
durability. However, it should be noted that the cost of nano-TiO2 is responsible for a severe increase in the cost of concrete
mixtures.(undefined
A design of experiments (DoE) approach to optimize cryogel manufacturing for tissue engineering applications
Marine origin polymers represent a sustainable and natural alternative to mammal counterparts
regarding the biomedical application due to their similarities with proteins and polysaccharides
present in extracellular matrix (ECM) in humans and can reduce the risks associated with zoonosis
and overcoming social- and religious-related constraints. In particular, collagen-based biomaterials
have been widely explored in tissue engineering scaffolding applications, where cryogels are of
particular interest as low temperature avoids protein denaturation. However, little is known about
the influence of the parameters regarding their behavior, i.e., how they can influence each other
toward improving their physical and chemical properties. Factorial design of experiments (DoE)
and response surface methodology (RSM) emerge as tools to overcome these difficulties, which are
statistical tools to find the most influential parameter and optimize processes. In this work, we
hypothesized that a design of experiments (DoE) model would be able to support the optimization
of the collagen-chitosan-fucoidan cryogel manufacturing. Therefore, the parameters temperature
(A), collagen concentration (B), and fucoidan concentration (C) were carefully considered to be
applied to the Boxâ Behnken design (three factors and three levels). Data obtained on rheological
oscillatory measurements, as well as on the evaluation of antioxidant concentration and adenosine
triphosphate (ATP) concentration, showed that fucoidan concentration could significantly influence
collagen-chitosan-fucoidan cryogel formation, creating a stable internal polymeric network promoted
by ionic crosslinking bonds. Additionally, the effect of temperature significantly contributed to
rheological oscillatory properties. Overall, the condition that allowed us to have better results, from
an optimization point of view according to the DoE, were the gels produced at −80ºC and composed
of 5% of collagen, 3% of chitosan, and 10% fucoidan. Therefore, the proposed DoE model was
considered suitable for predicting the best parameter combinations needed to develop these cryogels.This research was funded by the Portuguese Foundation for Science and Technology (FCT) for Ph.D. fellowship (D.N.C.) under the scope of the doctoral program Tissue Engineering, Regenerative Medicine and Stem Cells, ref. PD/BD/143044/2018, for postdoctoral fellowship (C.G.), ref. SFRH/BPD/94277/2013. This work has been partially funded by ERDF under the scope of the Atlantic Area Program through project EAPA_151/2016 (BLUEHUMAN)
The narrative model of therapeutic change: an exploratory study tracking innovative moments and protonarratives using state space grids
Despite the popularity of narrative approaches to the change in psychotherapy, a better understanding of how narrative transformation facilitates therapeutic change is needed. Research on innovative moments (IMs) has explored how IMs in psychotherapy evolve over time. We expand on past studies by exploring how IMs become aggregated in narrative threads, termed protonarratives, which come to constitute an alternative self-narrative at the conclusion of therapy. The results suggest that the good outcome case had a different pattern of IM integration within protonarratives, revealing greater flexibility than the poor outcome case. These results support the heuristic value of the concept of the protonarrative
Time limit at the minimum velocity of VO2max and intracyclic variation of the velocity of the centre of mass
The purpose of this study was to analyse the relationship
between time limit at the minimum velocity that elicits maximal
oxygen consumption (TLim-vVO2max) and intra-cyclic variations
of the velocity of the centre of mass (dv) in the four
competitive swimming techniques. Twelve elite male swimmers
SWIMMING BIOENERGETICS
Rev Port Cien Desp 190 6(Supl.2) 185–197
swam their own best technique until exhaustion at their previously
determined v O2max to assess TLim-v O2max. The test
was videotaped in the sagittal plan and the APAS software was
used to evaluate the horizontal velocity of the centre of mass
(Vcm) and its intra-cyclic variation (dv) per swimming technique.
Results pointed out that the strokes that presented
higher intra-cyclic variations also presented larger values of
TLim. Intra-cyclic speed fluctuations (dv) decreased during the
TLim test in the four strokes studied, probably due to fatigue.
Key words: VO2, intra-cyclic velocity variations, time limit, centre
of mass.Authors want to express their gratitude to the Portuguese
National Team, and the Portuguese Swimming Federation, for
their cooperation
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