867 research outputs found

    Effects of therapeutic ultrasound on the mechanical properties of skeletal muscles after contusion

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    CONTEXTUALIZAÇÃO: O ultra-som terapêutico (UST) é um recurso comumente aplicado na aceleração do reparo tecidual de lesões musculares. A absorção das ondas ultra-sônicas é determinada pela freqüência e pela intensidade, sendo que, em uma mesma intensidade, a profundidade atingida por 1MHz é maior quando comparada a 3MHz. OBJETIVO: Analisar o comportamento das propriedades mecânicas de músculos submetidos à lesão aguda por impacto e tratados com UST, utilizando as freqüências de 1 e 3MHz. MATERIAIS E MÉTODOS: Foram utilizadas 40 ratas Wistar (200,1±17,8g), divididas em quatro grupos: (1) controle; (2) lesão muscular sem tratamento; (3) lesão muscular tratada com UST de freqüência 1MHz (0,5W/cm²) e (4) lesão muscular tratada com UST de freqüência 3MHz (0,5W/cm²). A lesão foi provocada no músculo gastrocnêmio por mecanismo de impacto. O tratamento foi de cinco minutos diários durante seis dias consecutivos. Os músculos foram submetidos a ensaios mecânicos de tração em uma máquina universal de ensaios. RESULTADOS: As médias e desvios-padrão das propriedades mecânicas dos grupos lesionados e tratados com UST foram significativamente maiores quando comparadas ao grupo lesionado sem tratamento (p<0,05). Em destaque, a propriedade de rigidez que, com a aplicação do UST, teve acréscimo de aproximadamente 38%. CONCLUSÕES: A intervenção, por meio do UST, promoveu aumento das propriedades mecânicas nos músculos lesionados aproximando-as do grupo controle. Entretanto, não foi observada diferença significativa entre as propriedades mecânicas dos grupos tratados com ultra-som de freqüências 1MHz e 3MHz.BACKGROUND: Therapeutic ultrasound is a resource commonly applied to speed up tissue repair in muscle injuries. The absorption of the ultrasound waves is determined by their frequency and intensity. For a given intensity, the depth reached by 1MHz is greater than the depth reached by 3MHz. OBJECTIVE: To analyze the mechanical properties of muscles subjected to acute impact injury treated with therapeutic ultrasound at the frequencies of 1 and 3MHz. METHODS: Forty female Wistar rats (200.1±17.8g) were used, divided into four groups: (1) control; (2) muscle injury without treatment; (3) muscle injury treated with therapeutic ultrasound at the frequency of 1MHz (0.5W/cm²); and (4) muscle injury treated with therapeutic ultrasound at the frequency of 3MHz (0.5W/cm²). The injury was produced in the gastrocnemius muscle by means of an impact mechanism. The treatment consisted of a single five-minute session per day, for six consecutive days. The muscles were subjected to mechanical traction tests in a universal test machine. RESULTS: Means and standard deviations for the mechanical properties of the injured groups that received therapeutic ultrasound were significantly greater than those of the injured group without treatment (p<0.05). The property of stiffness should be highlighted: the application of therapeutic ultrasound increased muscle stiffness by approximately 38%. CONCLUSIONS: Therapeutic ultrasound increased the mechanical properties of the injured muscles, and brought them to a level close to the control group. However, no significant difference in mechanical properties was observed between the groups treated with ultrasound at the frequencies of 1MHz and 3MHz

    Poor sleep quality and oral health among older Brazilian adults

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    Objectives: This study evaluates the association between normative and subjective oral health measures and poor self‐reported sleep quality among community‐dwelling older adults in Brazil. / Methods: This was a cross‐sectional study with data from the Brazilian Longitudinal Study of Aging. The dependent variable was the poor sleep quality. Independent variables of interest included number of teeth and self‐reported impact of oral health on eating/chewing and on maintaining emotional stability. / Results: Poor sleep quality was reported by 17.8 (95% CI 16.6; 19.2) of the participants, 29% of the participants were edentulous, and 30% had 20 or more teeth. Impacts of oral health on eating and maintaining emotional stability was found among 33.3% and 20% of the older adults, respectively. After adjusting for all oral health measures and covariates, the magnitude of the associations between the number of teeth and sleep quality was attenuated. Sleep quality was related to oral health impacts on eating (OR 1.19 [95% CI 1.00; 1.41]) and on emotional stability (OR 1.51 [95% CI 1.21; 1.87]). / Conclusions: This study found an association between oral health and sleep quality emphasizing the importance of oral health to general health

    Differences in the prevalence of prediabetes, undiagnosed diabetes and diagnosed diabetes and associated factors in cohorts of Brazilian and English older adults

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    OBJECTIVE: To analyse differences in the prevalence of prediabetes (PD), undiagnosed diabetes (UDD) and diagnosed diabetes (DD) and associated factors between Brazilian and English older adults. DESIGN: Cross-sectional study. SETTING: England and Brazil. PARTICIPANTS: 5301 participants of the English Longitudinal Study of Ageing study and 1947 participants of the Brazilian Longitudinal Study of Aging study classified as non-diabetics, PD, UDD and DD. RESULTS: The prevalence of PD, UDD and DD was 48·6, 3 and 9·6 % in England and 33, 6 and 20 % in Brazil. In England, the increase in age, non-white skin colour, smoking, general obesity and abdominal obesity were associated with PD, UDD and DD, whereas hypertriglyceridaemia, low HDL levels, hypertension and stroke were associated with UDD and DD. In Brazil, the increase in age was associated with DD and UDD, non-white skin colour and smoking were associated with UDD and abdominal obesity and hypertriglyceridaemia were associated with all three conditions. CVD in England and schooling in Brazil were associated with PD and DD. A sedentary lifestyle was associated with DD in both samples. CONCLUSIONS: The prevalence of diabetes was higher in the Brazilian sample. Different associated factors were found in the two samples, which may be related to differences in nutritional transition, access to healthcare services and the use of such services

    Ponderomotive and resonant effects in the acceleration of particles by electromagnetic modes

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    Funding: U.K. Science and Engineering Research Council under Grant No. EP/N028694/1 (R.A.C.).In the present analysis, we study the dynamics of charged particles under the action of slowly modulated electromagnetic carrier waves. With the use of a high-frequency laser mode along with a modulated static magnetic wiggler, we show that the ensuing total field effectively acts as a slowly modulated high-frequency beat-wave field typical of inverse free-electron laser schemes. This effective resulting field is capable of accelerating particles in much the same way as space-charge wake fields do in plasma accelerators, with the advantage of being more stable than plasma related methods. Acceleration occurs as particles transition from ponderomotive to resonant regimes, so we develop the ponder- omotive formalism needed to examine this problem. The ponderomotive formalism includes terms that, although not discussed in the usual applications of the approximation, are nevertheless of crucial importance in the vicinity of resonant capture. The role of these terms is also briefly discussed in the context of generic laser-plasma interactions.PostprintPeer reviewe

    Lean Principles in Vertical Farming: A Case Study

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    Vertical farming (VF) has been recognised as an important tool for managing future food security, yet economic viability poses a significant hurdle with the vast majority of farms closing within three years. The application of lean principles poses an opportunity to address inefficiencies, such as significant labour expenditure, but existing literature is yet to consider process improvement methodologies in VF. In this paper, an established framework for lean implementation is applied to an industry case study providing techniques for process improvement. This work is novel and crucial for workflow standardisation and higher profit margins in this emerging sector

    Does undiagnosed diabetes mitigate the association between diabetes and cognitive impairment? Findings from the ELSI‐Brazil study

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    Background: Type 2 diabetes mellitus (T2DM) is associated with cognitive impairment. However, most of the evidence has been based on self‐reported T2DM, and undiagnosed diabetes has not been considered as a separate category. We aimed to examine the extent to which undiagnosed diabetes modifies the association between diabetes and cognitive impairment in a representative sample of Brazilian adults aged 50 years and older. / Methods: We analyzed baseline data from 1944 participants of the Brazilian Longitudinal Study of Aging (ELSI‐Brazil) conducted from 2015 to 2016. Diabetes was evaluated based on self‐reported doctor diagnosis and glycosylated hemoglobin levels. Participants were classified as diabetics (D), undiagnosed diabetics (UDD), or nondiabetics (ND). Cognitive function was assessed by word list learning and verbal fluency tests. Three multiple logistic regression models were used to evaluate the changes in the strength of the associations. / Results: Participants with diabetes had 49% greater odds of exhibiting impaired memory than nondiabetics (odds ratio [OR] = 1.49; 95% CI: 1.01‐2.20). By combining UDD and ND, the association between diabetes and impaired memory was attenuated by 2.0%, losing its statistical significance (OR = 1.46; 95% CI: 0.98‐2.17). By combining UDD and D, the association was attenuated by 7.4% (OR = 1.38; 95% CI: 1.01‐1.90). No significant association was found between T2DM and impaired verbal fluency. / Conclusion: This study found an association between T2DM and impaired memory but not with impaired verbal fluency. When UDD individuals are considered diabetics, this association is attenuated; when UDD individuals are considered as ND, this association is attenuated to the extent that it loses its statistical significance, affecting thus the clinical interpretation

    Racial inequities in tooth loss among older Brazilian adults: A decomposition analysis

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    OBJECTIVE: To determine the extent to which racial inequities in tooth loss and functional dentition are explained by individual socioeconomic status, smoking status and frequency/reason for the use of dental services. METHODS: Data came from the Brazilian Longitudinal Study of Ageing, a nationally representative sample of community-dwelling people aged 50 years and over. Tooth loss and functional dentition (ie 20+ natural teeth) were the outcomes. The main explanatory variable was self-classified race. Covariates included dental visits in the past 12 months, dental visits for check-ups only, smoking status, self-reported chronic conditions, depression and cognitive function. Logistic regression and Blinder-Oaxaca decomposition analysis were used to estimate the share of each factor in race-related tooth loss inequities. RESULTS: The analytical sample comprised of 7126 respondents. While the prevalence of functional dentition in White Brazilians was 37% (95% CI: 33.5;40.9), it was 29% (95% CI: 26.4;31.6) among Browns and 30% (95% CI: 25.1;35.4) among Blacks. The average number of lost teeth among Whites, Browns and Blacks were 18.7 (95% CI: 17.8;19.6), 20.4 (95% CI: 19.7;21.1) and 20.8 (95% CI: 19.5;22.0), respectively. Decomposition analysis showed that the selected covariates explained 71% of the racial inequalities in tooth loss. Dental visits in the previous year and smoking status explained nearly half of race-related gaps. Other factors, such as per capita income, education and cognitive status, also had an important contribution to the examined inequalities. The proportion of racial inequities in tooth loss that was explained by dental visits (frequency and reason) and smoking status decreased from 40% for those 50-59 years of age to 22% among participants aged 70-79 years. CONCLUSIONS: Frequency and reason for dental visits and smoking status explained nearly half of the racial inequity in tooth loss among Brazilian older adults. The Brazilian Family Health Strategy Program should target older adults from racial groups living in deprived areas

    Evaluation of the cytotoxicity (HepG2) and chemical composition of polar extracts from the ruderal species Coleostephus myconis (L.) Rchb.f.

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    oleostephus myconis (L.) Rchb.f. (Asteraceae) is a highly disseminated plant species with ruderal and persistent growth. Owing to its advantageous agronomic properties, C. myconis might have industrial applications. However, this species needs to be comprehensively characterized before any potential use. In a previous study, the phenolic composition and antioxidant activity of different C. myconis tissues were characterized. This investigation was extended to examine the cytotoxic potential of selected plant tissues (flowers and green parts) using a HepG2 cell line by utilizing the lysosomal neutral red uptake assay or mitochondrial (3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide assay. In addition, the macronutrients content, lipophilic compounds (fatty acids, tocopherols), and amino acids were also determined. C. myconis flowers were used in the senescence stage, which was previously identified as the stage that presented maximal phenolic content and highest antioxidant activity. In contrast, stems and leaves were employed due to their high biomass proportion. Regarding cytotoxicity, mitochondrial and lysosomal damage was only significant when HepG2 cells were exposed to the highest extract concentrations (stems and leaves, 0.9 mg/ml; senescent flowers, 0.3 mg/ml). Chemically, the senescent flowers were mostly characterized by their high levels of fat, amino acids (especially threonine), oleic acid, β-, and γ-tocopherol, while stems and leaves contained high concentrations of carbohydrates, linolenic acid, and α-tocopherol. In general, these results provide information regarding the threshold concentrations of C. myconis extracts that might be used in different applications without toxicity hazards.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support to REQUIMTE (PEst-C/EQB/LA0006/2014) and to CIMO (UID/AGR/00690/2013). J.C.M. Barreira, Carla Costa, and Filipa B. Pimentel thank FCT, POPH-QREN, and FSE for their grants (SFRH/BPD/72802/2010, SFRH/BPD/96196/2013 and SFRH/BD/109042/2015, respectively)
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