Acoustic images of gel dosimetry phantoms

AbstractThis work presents Vibro-acoustography (VA) as a tool to visualize absorbed dose in a polymer gel dosimetry phantom. VA relies on the mechanical excitation introduced by the acoustic radiation force of focused modulated ultrasound in a small region of the object. A hydrophone or microphone is used to measure the sound emitted from the object in response to the excitation, and by using the amplitude or phase of this signal, an image of the object can be generated. To study the phenomena of dose distribution in a gel dosimetry phantom, continuous wave (CW), tone burst and multi-frequency VA were used to image this phantom. The phantom was designed using ‘MAGIC’ gel polymer with addition of glass microspheres at 2% w/w having an average diameter range between 40–75 μm. The gel was irradiated using conventional 10 MeV X-rays from a linear accelerator. The field size in the surface of the phantom was 1.0×1.0 cm2 and a source-surface distance (SSD) of 100 cm. The irradiated volume corresponds to an approximately 8.0 cm3, where a dose of 50 gray was delivered to the gel. Polymer gel dosimeters are sensitive to radiation-induced chemical changes that occur in the irradiated polymer. VA images of the gel dosimeter showed the irradiate area. It is concluded that VA imaging has potential to visualize dose distribution in a polymer gel dosimeter

ProFlex: A Probabilistic and Flexible Data Storage Protocol for Heterogeneous Wireless Sensor Networks

This paper presents ProFlex, a proactive data distribution protocol for heterogeneous wireless sensor networks (HWSNs). ProFlex guarantees robustness in data retrieval by intelligently managing data replication among selected storage nodes in the network. Contrarily to related protocols in the literature, ProFlex considers the resource constraints of sensor nodes and constructs multiple data replication structures, which are managed by more powerful nodes. Additionally, ProFlex takes profit of the higher communication range of such powerful nodes in the network and use the long link to improve data distribution. When compared with Supple -- a related protocol, we show by simulation that Proflex increases the network resilience under failures circumstances, decreases the overhead of transmitted messages, and decreases the number of hops to find a specific data in the network.Cet article porte sur la proposition d'un protocole de données proactif de distribution pour les réseaux de capteurs sans fil hétérogènes (HWSNs). Notre protocole, ProFlex, garantit la robustesse de la récupération des données grâce à sa gestion intelligente de la réplication des données entre les nœuds de stockage sélectionnés dans le réseau. Contrairement à d'autres protocoles dans la littérature, ProFlex considère les contraintes de ressources de capteurs et construit plusieurs structures de réplication des données, qui sont gérés par des nœuds plus puissants. En outre, ProFlex profite de la meilleure communication radio de ces nœuds plus puissants et utilise ces longues portée pour améliorer la distribution des données. Nous avons comparé ProFlex avec le protocole Supple et nous avons montré par simulation que Proflex augmente la résilience du réseau, même dans des circonstances des pertes de messages, diminue la surcharge de messages transmis, et diminue le nombre de sauts nécessaire pour trouver un ensemble de données spécifiques dans le réseau

Electromagnetic energy harvesting using magnetic levitation architectures: a review

Motion-driven electromagnetic energy harvesters have the ability to provide low-cost and customizable electric powering. They are a well-suited technological solution to autonomously supply a broad range of high-sophisticated devices. This paper presents a detailed review focused on major breakthroughs in the scope of electromagnetic energy harvesting using magnetic levitation architectures. A rigorous analysis of twenty-one design configurations was made to compare their geometric and constructive parameters, optimization methodologies and energy harvesting performances. This review also explores the most relevant models (analytical, semi-analytical, empirical and finite element method) already developed to make intelligible the physical phenomena of their transduction mechanisms. The most relevant approaches to model each physical phenomenon of these transduction mechanisms are highlighted in this paper. Very good agreements were found between experimental and simulation tests with deviations lower than 15%. Moreover, the external motion excitations and electric energy harvesting outputs were also comprehensively compared and critically discussed. Electric power densities up to 8 mW/cm^3 (8 kW/m^3) have already been achieved; for resistive loads, the maximum voltage and current were 43.4 V and 150 mA, respectively, for volumes up to 235 cm^3. Results highlight the potential of these harvesters to convert mechanical energy into electric energy both for large-scale and small-scale applications. Moreover, this paper proposes future research directions towards efficiency maximization and minimization of energy production costs.in publicatio

Effects of Ibuprofen intake in muscle damage, body temperature and muscle power in Paralympic powerlifting athletes

The aim of this study is to evaluate the effect of ingesting ibuprofen on post-workout recovery of muscle damage, body temperature and muscle power indicators in Paralympic powerlifting athletes. The study was carried out with eight Paralympic powerlifting athletes (aged 27.0 ± 5.3 years and 79.9 ± 25.5 kg of body mass) competing at the national level, with a minimum training experience of 12 months, who all submitted to two experimental conditions: Ibuprofen (2 × 00 mg) and control. The maximal isometric force of the upper limbs and rate of force development, thermography, and serum biochemical analyzes of creatine kinase, lactate dehydrogenase, aspartate aminotransferase and alanine aminotransferase were measured before, after, 24 h after and 48 h after the intervention. Maximal isometric force only decreased in the placebo condition, which increased back to baseline levels, while no substantial decline in baseline force was seen in the ibuprofen condition, although no effect for exercise condition was detected. After the exercise, the rate of force development decreased significantly for both conditions and did not exceed baseline levels again after 48 h. Muscle temperature decreased significantly at 48-h post-exercise in the placebo condition, when compared with the previous day of measurement; and deltoid muscle temperature at 48-h post-exercise was higher with the ibuprofen condition. Although the results indicate some positive effects of ibuprofen use, they do not enable a clear statement regarding its positive effects on muscle function and muscle damage. Ibuprofen seems to have caused a delay in the anti-inflammatory response following exercise.publishedVersio

A vis\~ao da BBChain sobre o contexto tecnol\'ogico subjacente \`a ado\c{c}\~ao do Real Digital

We explore confidential computing in the context of CBDCs using Microsoft's CCF framework as an example. By developing an experiment and comparing different approaches and performance and security metrics, we seek to evaluate the effectiveness of confidential computing to improve the privacy, security, and performance of CBDCs. Preliminary results suggest that confidential computing could be a promising solution to the technological challenges faced by CBDCs. Furthermore, by implementing confidential computing in DLTs such as Hyperledger Besu and utilizing frameworks such as CCF, we increase transaction confidentiality and privacy while maintaining the scalability and interoperability required for a global digital financial system. In conclusion, confidential computing can significantly bolster CBDC development, fostering a secure, private, and efficient financial future. -- Exploramos o uso da computa\c{c}\~ao confidencial no contexto das CBDCs utilizando o framework CCF da Microsoft como exemplo. Via desenvolvimento de experimentos e compara\c{c}\~ao de diferentes abordagens e m\'etricas de desempenho e seguran\c{c}a, buscamos avaliar a efic\'acia da computa\c{c}\~ao confidencial para melhorar a privacidade, seguran\c{c}a e desempenho das CBDCs. Resultados preliminares sugerem que a computa\c{c}\~ao confidencial pode ser uma solu\c{c}\~ao promissora para os desafios tecnol\'ogicos enfrentados pelas CBDCs. Ao implementar a computa\c{c}\~ao confidencial em DLTs, como o Hyperledger Besu, e utilizar frameworks como o CCF, aumentamos a confidencialidade e a privacidade das transa\c{c}\~oes, mantendo a escalabilidade e a interoperabilidade necess\'arias para um sistema financeiro global e digital. Em conclus\~ao, a computa\c{c}\~ao confidencial pode refor\c{c}ar significativamente o desenvolvimento do CBDC, promovendo um futuro financeiro seguro, privado e eficiente.Comment: Comments: 11 pages, 8 figures, in (Brazilian) Portugues

The cdh1 c.1901c>t variant: A founder variant in the portuguese population with severe impact in mrna splicing

Hereditary diffuse gastric cancer (HDGC) caused by CDH1 variants predisposes to early-onset diffuse gastric (DGC) and lobular breast cancer (LBC). In Northern Portugal, the unusually high number of HDGC cases in unrelated families carrying the c.1901C>T variant (formerly known as p.A634V) suggested this as a CDH1-founder variant. We aimed to demonstrate that c.1901C>T is a bona fide truncating variant inducing cryptic splicing, to calculate the timing of a potential founder effect, and to characterize tumour spectrum and age of onset in carrying families. The impact in splicing was proven by using carriers’ RNA for PCR-cloning sequencing and allelic expression imbalance analysis with SNaPshot. Carriers and noncarriers were haplotyped for 12 polymorphic markers, and the decay of haplotype sharing (DHS) method was used to estimate the time to the most common ancestor of c.1901C>T. Clinical information from 58 carriers was collected and analysed. We validated the cryptic splice site within CDH1-exon 12, which was preferred over the canonical one in 100% of sequenced clones. Cryptic splicing induced an out-of-frame 37bp deletion in exon 12, premature truncation (p.Ala634ProfsTer7), and consequently RNA mediated decay. The haplotypes carrying the c.1901C>T variant were found to share a common ancestral estimated at 490 years (95% Confidence Interval 445–10,900). Among 58 carriers (27 males (M)–31 females (F); 13–83 years), DGC occurred in 11 (18.9%; 4M–7F; average age 33 ± 12) and LBC in 6 females (19.4%; average age 50 ± 8). Herein, we demonstrated that the c.1901C>T variant is a loss-of-function splice-site variant that underlies the first CDH1-founder effect in Portugal. Knowledge on this founder effect will drive genetic testing of this specific variant in HDGC families in this geographical region and allow intrafamilial penetrance analysis and better estimation of variant-associated tumour risks, disease age of onset, and spectrum.This research and its authors were funded by FEDER—Fundo Europeu de Desenvolvi-mento Regional funds through the COMPETE 2020—Operational Programme for Competitiveness and Internationalization (POCI), Portugal 2020, and by Portuguese funds through FCT—Fundação para a Ciência e a Tecnologia/Ministério da Ciência, Tecnologia e Inovação in the framework of the project “Institute for Research and Innovation in Health Sciences” (POCI-01-0145-FEDER-007274) and LEGOH (PTDC/BTM-TEC/6706/2020). This work was also financed by the projects NORTE-01-0145-FEDER-000003 (DOCnet)—supported by Norte Portugal Regional Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF)—project POCI-01-0145-FEDER-016390 (CancelStem) and PTDC/BTM-TEC/30164/2017 (3DChroMe), funded by ERDF, POCI, and FCT

Hepatitis C in Brazil: lessons learned with boceprevir and telaprevir

In 2012, the first-generation protease inhibitors telaprevir (TVR) and boceprevir (BOC) were introduced in the Brazilian health system for treatment of chronic hepatitis C, after their approval by the National Committee for Health Technology Incorporation (CONITEC). However, these medicines were discontinued in 2015. The short period of use in therapy and their high cost require a discussion about the consequences for patients and for the health system of the early incorporation of new therapies. The article presents a qualitative analysis of the incorporation process of both medications in Brazil and the results of a multicenter study that included patients treated with BOC or TVR between January 2011 and December 2015 in five Brazilian cities. The study included 855 patients (BOC: n=247) and (TVR: n=608). The document analysis showed that CONITEC’s decision to incorporate BOC and TVR was based on results of phase III clinical trials that compared sustained virologic response (SVR) rates of patients treated with BOC and TVR with rates of those that received placebo. However, these studies included a low percentage of cirrhotic patients. The SVR rates observed in this multicenter study were worse than clinical trials pointed out (BOC: 45.6%; TVR: 51.8%), but similar to those achieved with previously adopted therapies. The discontinuation rate due to adverse events was (BOC: 15.4%; TVR: 12.7%). Based on these unsatisfactory results, the study brings a discussion that goes beyond the therapy outcomes, exploring the incorporation of these high-cost medicines and the related decision-making process, contributing to future decisions in medicine policies and in the treatment of chronic hepatitis C

Late Onset Neuromyelitis Optica Spectrum Disorders (LONMOSD) from a Nationwide Portuguese Study: Anti-AQP4 Positive, Anti-MOG Positive and Seronegative Subgroups

Introduction: Several neuroimmunological disorders have distinct phenotypes according to the age of onset, as in multiple sclerosis or myasthenia gravis. It is also described that late onset NMOSD (LONMOSD) has a different phenotype. Objective: To describe the clinical/demographic characteristics of the LONMOSD and distinguish them from those with early onset (EONMOSD). Methods: From a nationwide Portuguese NMOSD study we analyzed the clinical/demographic characteristics of the LONMOSD. Results: From the 180 Portuguese patients 45 had disease onset after 50 years old, 80% were female. 23 had anti-AQP4 antibodies (51.1%), 13 anti-MOG antibodies (28.9%) and 9 were double seronegative (20.0%). The most common presenting phenotypes in LONMOSD were transverse myelitis (53.3%) and optic neuritis (26.7%), without difference from EONMOSD (p = 0.074). The mean EDSS for LONMOSD was 6.0 (SD=2.8), after a mean follow-up time of 4.58 (SD=4.47) years, which was significantly greater than the mean EDSS of EONMOSD (3.25, SD=1.80)(p = 0.022). Anti-AQP4 antibodies positive LONMOSD patients had increased disability compared to anti-MOG antibodies positive LONMOSD (p = 0.022). The survival analysis showed a reduced time to use a cane for LONMOSD, irrespective of serostatus (p<0.001). Conclusions: LONMOSD has increased disability and faster progression, despite no differences in the presenting clinical phenotype were seen in our cohort.info:eu-repo/semantics/publishedVersio

Effects of Resistance Training on Oxidative Stress Markers and Muscle Damage in Spinal Cord Injured Rats

Background: Spinal cord injury (SCI) is a condition that affects the central nervous system, is characterized by motor and sensory impairments, and impacts individuals’ lives. The objective of this study was to evaluate the effects of resistance training on oxidative stress and muscle damage in spinal cord injured rats. Methodology: Forty Wistar rats were selected and divided equally into five groups: Healthy Control (CON), Sham (SHAM) SCI Untrained group (SCI-U), SCI Trained group (SCI- T), SCI Active Trained group (SCI- AT). Animals in the trained groups were submitted to an incomplete SCI at T9. Thereafter, they performed a protocol of resistance training for four weeks. Results: Significant differences in muscle damage markers and oxidative stress in the trained groups, mainly in SCI- AT, were found. On the other hand, SCI- U group presented higher levels of oxidative stress and biomarkers of LDH and AST. Conclusion: The results highlight that resistance training promoted a decrease in oxidative stress and a significative response in muscle damage markers. Keywords: spinal cord injury; resistance training; oxidative stress; muscle damag

Hydrogen peroxide production regulates the mitochondrial function in insulin resistant muscle cells: Effect of catalase overexpression

AbstractThe mitochondrial redox state plays a central role in the link between mitochondrial overloading and insulin resistance. However, the mechanism by which the ROS induce insulin resistance in skeletal muscle cells is not completely understood. We examined the association between mitochondrial function and H2O2 production in insulin resistant cells. Our hypothesis is that the low mitochondrial oxygen consumption leads to elevated ROS production by a mechanism associated with reduced PGC1α transcription and low content of phosphorylated CREB. The cells were transfected with either the encoded sequence for catalase overexpression or the specific siRNA for catalase inhibition. After transfection, myotubes were incubated with palmitic acid (500μM) and the insulin response, as well as mitochondrial function and fatty acid metabolism, was determined. The low mitochondrial oxygen consumption led to elevated ROS production by a mechanism associated with β-oxidation of fatty acids. Rotenone was observed to reduce the ratio of ROS production. The elevated H2O2 production markedly decreased the PGC1α transcription, an effect that was accompanied by a reduced phosphorylation of Akt and CREB. The catalase transfection prevented the reduction in the phosphorylated level of Akt and upregulated the levels of phosphorylated CREB. The mitochondrial function was elevated and H2O2 production reduced, thus increasing the insulin sensitivity. The catalase overexpression improved mitochondrial respiration protecting the cells from fatty acid-induced, insulin resistance. This effect indicates that control of hydrogen peroxide production regulates the mitochondrial respiration preventing the insulin resistance in skeletal muscle cells by a mechanism associated with CREB phosphorylation and β-oxidation of fatty acids