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Visualization of training effectiveness is critical to patients' confidence and eventual rehabilitation. Here, an innovative magnetoinductive pressure sensor is proposed for monitoring hand rehabilitation in stroke hemiplegic patients. It couples the giant magneto and stress-impedance effects of a square spiral amorphous wire with the giant magnetoelastic effect of a polymer magnet (NdFeB@PDMS). The addition of the magnetoelastic layer results in a sensitivity improvement of 178%, a wide sensing range (up to 1 MPa), fast response/recovery times (40 ms), and excellent mechanical robustness (over 15 000 cycles). Further integration with an LC oscillation circuit enables frequency adjustment into the MHz range resulting in a sensitivity of 6.6% kPa-1 and outstanding linearity (R2 = â 0.99717) over a stress range of up to 100 kPa. When attached to a commercial split-fingerboard, the sensor is capable of dynamically monitoring the force in each finger, providing a reading of the rehabilitation process. Unlike conventional inductive sensors, the sensor is based on an inductive force-responsive material (amorphous wire), which significantly boosts the sensitivity. The approach also demonstrates the potential of magnetoelasticity in static pressure sensing, which is highly sensitive to dynamic pressure only through electromagnetic induction. This makes it more suitable for long-term and continuous human health monitoring.
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Mãos , Humanos , Mãos/fisiologia , Pressão , Elasticidade , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Impedância Elétrica , ImãsRESUMO
In this work, to maximize the unique attributes of reduced graphene oxide (RGO) for excellent microwave absorption, the ultralight RGO aerogels with improved dispersion and interface polarization performance were fabricated via a facile cation-assisted hydrothermal treatment process. The prepared RGO/paraffin composite exhibits excellent microwave absorption (MA) performance in a wideband frequency range of 8.0 â¼ 18.0 GHz with an ultralow absorbent content of 0.5 wt.%. Such performance is comparable with most previously reported results on RGO-based composites but required much higher absorbent content. The mechanisms for the enhancement of polarization relaxation loss and conductive loss were investigated in detail. This study provides a promising and facile method for preparing RGO-based excellent microwave absorption materials with ultra-low filler content, which is significant for designing efficient MA absorbers.
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BACKGROUND: Anaemia is a condition where the number of red blood cells (and consequently their oxygen-carrying capacity) is insufficient to meet the body's physiologic needs. Fortification of wheat flour is deemed a useful strategy to reduce anaemia in populations. OBJECTIVES: To determine the benefits and harms of wheat flour fortification with iron alone or with other vitamins and minerals on anaemia, iron status and health-related outcomes in populations over two years of age. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, CINAHL, and other databases up to 4 September 2019. SELECTION CRITERIA: We included cluster- or individually randomised controlled trials (RCT) carried out among the general population from any country aged two years and above. The interventions were fortification of wheat flour with iron alone or in combination with other micronutrients. Trials comparing any type of food item prepared from flour fortified with iron of any variety of wheat were included. DATA COLLECTION AND ANALYSIS: Two review authors independently screened the search results and assessed the eligibility of studies for inclusion, extracted data from included studies and assessed risk of bias. We followed Cochrane methods in this review. MAIN RESULTS: Our search identified 3048 records, after removing duplicates. We included nine trials, involving 3166 participants, carried out in Bangladesh, Brazil, India, Kuwait, Phillipines, Sri Lanka and South Africa. The duration of interventions varied from 3 to 24 months. One study was carried out among adult women and one trial among both children and nonpregnant women. Most of the included trials were assessed as low or unclear risk of bias for key elements of selection, performance or reporting bias. Three trials used 41 mg to 60 mg iron/kg flour, two trials used less than 40 mg iron/kg and three trials used more than 60 mg iron/kg flour. One trial employed various iron levels based on type of iron used: 80 mg/kg for electrolytic and reduced iron and 40 mg/kg for ferrous fumarate. All included studies contributed data for the meta-analyses. Seven studies compared wheat flour fortified with iron alone versus unfortified wheat flour, three studies compared wheat flour fortified with iron in combination with other micronutrients versus unfortified wheat flour and two studies compared wheat flour fortified with iron in combination with other micronutrients versus fortified wheat flour with the same micronutrients (but not iron). No studies included a 'no intervention' comparison arm. None of the included trials reported any other adverse side effects (including constipation, nausea, vomiting, heartburn or diarrhoea). Wheat flour fortified with iron alone versus unfortified wheat flour (no micronutrients added) Wheat flour fortification with iron alone may have little or no effect on anaemia (risk ratio (RR) 0.81, 95% confidence interval (CI) 0.61 to 1.07; 5 studies; 2200 participants; low-certainty evidence). It probably makes little or no difference on iron deficiency (RR 0.43, 95% CI 0.17 to 1.07; 3 studies; 633 participants; moderate-certainty evidence) and we are uncertain about whether wheat flour fortified with iron increases haemoglobin concentrations by an average 3.30 (g/L) (95% CI 0.86 to 5.74; 7 studies; 2355 participants; very low-certainty evidence). No trials reported data on adverse effects in children, except for risk of infection or inflammation at the individual level. The intervention probably makes little or no difference to risk of Infection or inflammation at individual level as measured by C-reactive protein (CRP) (moderate-certainty evidence). Wheat flour fortified with iron in combination with other micronutrients versus unfortified wheat flour (no micronutrients added) Wheat flour fortified with iron, in combination with other micronutrients, may or may not decrease anaemia (RR 0.95, 95% CI 0.69 to 1.31; 2 studies; 322 participants; low-certainty evidence). It makes little or no difference to average risk of iron deficiency (RR 0.74, 95% CI 0.54 to 1.00; 3 studies; 387 participants; moderate-certainty evidence) and may or may not increase average haemoglobin concentrations (mean difference (MD) 3.29, 95% CI -0.78 to 7.36; 3 studies; 384 participants; low-certainty evidence). No trials reported data on adverse effects in children. Wheat flour fortified with iron in combination with other micronutrients versus fortified wheat flour with same micronutrients (but not iron) Given the very low certainty of the evidence, the review authors are uncertain about the effects of wheat flour fortified with iron in combination with other micronutrients versus fortified wheat flour with same micronutrients (but not iron) in reducing anaemia (RR 0.24, 95% CI 0.08 to 0.71; 1 study; 127 participants; very low-certainty evidence) and in reducing iron deficiency (RR 0.42, 95% CI 0.18 to 0.97; 1 study; 127 participants; very low-certainty evidence). The intervention may make little or no difference to the average haemoglobin concentration (MD 0.81, 95% CI -1.28 to 2.89; 2 studies; 488 participants; low-certainty evidence). No trials reported data on the adverse effects in children. Eight out of nine trials reported source of funding with most having multiple sources. Funding source does not appear to have distorted the results in any of the assessed trials. AUTHORS' CONCLUSIONS: Eating food items containing wheat flour fortified with iron alone may have little or no effect on anaemia and probably makes little or no difference in iron deficiency. We are uncertain on whether the intervention with wheat flour fortified with iron increases haemoglobin concentrations improve blood haemoglobin concentrations. Consuming food items prepared from wheat flour fortified with iron, in combination with other micronutrients, has little or no effect on anaemia, makes little or no difference to iron deficiency and may or may not improve haemoglobin concentrations. In comparison to fortified flour with micronutrients but no iron, wheat flour fortified with iron with other micronutrients, the effects on anaemia and iron deficiency are uncertain as certainty of the evidence has been assessed as very low. The intervention may make little or no difference to the average haemoglobin concentrations in the population. None of the included trials reported any other adverse side effects. The effects of this intervention on other health outcomes are unclear.
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Anemia/dietoterapia , Farinha , Alimentos Fortificados , Ferro/administração & dosagem , Triticum , Adolescente , Adulto , Anemia/sangue , Criança , Pré-Escolar , Ácido Edético/administração & dosagem , Feminino , Compostos Férricos/administração & dosagem , Compostos Ferrosos/administração & dosagem , Fumaratos , Hemoglobina A/análise , Humanos , Lactente , Deficiências de Ferro , Masculino , Micronutrientes/administração & dosagem , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Adulto JovemRESUMO
Health promotion, screening, diagnosis, and disease prevention are essential services of quality routine antenatal care for pregnant adult and adolescent women. Supplementation programmes in pregnancy, generally implemented in the context of antenatal care services, have had less than optimal results in many countries, generally attributed to limited access, low coverage, and reduced adherence to the recommended regimens and counselling. The World Health Organization Department of Nutrition for Health and Development, in collaboration with the United Nations Children's Fund and Nutrition International, convened the technical consultation "Multiple micronutrient supplements in pregnancy: Implementation considerations for successful incorporation into existing programmes." The objectives of the technical consultation were to (a) examine implementation experiences of micronutrient supplementation interventions in pregnant women, lessons learnt, and best practices; (b) discuss programmatic and technical considerations of interventions on multiple micronutrient supplementation in pregnant women in low-, middle-, and high-income countries; and (c) identify implementation considerations that can be useful to scaling up efforts by national policymaker and their advisors considering multiple micronutrient supplementation in pregnant women as part of existing antenatal care programmes as well as other delivery platforms. The consultation was based on presentations of background papers, case studies, and plenary discussions. Country representatives were asked to discuss the context of micronutrient supplementation for their countries and share implementation challenges they faced. This paper provides the background and rationale of the technical consultation, synopsises the presentations, and provides a summary of the main considerations and conclusions reached during plenary discussions.
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Suplementos Nutricionais , Micronutrientes , Cuidado Pré-Natal , África Subsaariana , Ásia , Feminino , Humanos , Nicarágua , Gravidez , Cuidado Pré-Natal/métodos , Cuidado Pré-Natal/normas , Qualidade da Assistência à SaúdeRESUMO
The dramatic growth of smart wearable electronics has generated a demand for conductive hydrogels due to their tunability, stimulus responsiveness, and multimodal sensing capabilities. However, the substantial trade-off between mechanical and electrical properties hinders their multifunctionality. Here, we report a double-network hydrogel composite that features a conductive "highway" constructed using magnetic-field-aligned nickel nanowires and liquid metal. The liquid metal fills the gaps between the aligned nickel nanowires. Such interconnected structures can form efficient conductive paths at low filler content, resulting in high conductivity (1.11 × 104 S/m) and mechanical compliance (Young's modulus, 89 kPa; toughness, 721 kJ/m3). When used as a wearable sensor, the hydrogel displays a high sensitivity and fast response for wireless motion detection and human-machine interaction. Furthermore, by exploiting its outstanding conductivity and electrical heating capacity, the hydrogel integrates electromagnetic shielding and thermal management functionalities. Owing to these all-around properties, our design offers a broader platform for expanding hydrogel applications.
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With the miniaturization and integration of electronic components in wireless communication and wearable devices, the demand for low-cost flexible composites with temperature-stable high dielectric constant and low loss has substantially increased. However, such comprehensive properties are fundamentally difficult to combine for conventional conductive and ceramic composites. Here, we develop silicone elastomer (SE) composites based on hydrothermally grown MoS2 on tissue paper-derived cellulose carbon (CC). Such design promoted the formation of microcapacitors, multiple interfaces, and defects reinforcing interfacial and defect polarizations and resulting in a high dielectric constant of 9.83 at 10 GHz with low filler loading of 15 wt %. Unlike highly conductive fillers, MoS2@CC with low conductivity ensured a very low loss tangent of 7.6 × 10-3, which was also influenced by the filler dispersion and adhesion to the matrix. Apart from breaking the typical conflict between high dielectric constant and low losses of traditional conductive composites, MoS2@CC SE composites were highly flexible with temperature-stable dielectric properties making them attractive as flexible substrates in microstrip antenna applications and extreme environment electronics. Moreover, recycling from waste tissue paper makes them potential candidates as low-cost and sustainable dielectric composites.
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Achieving the health and well-being related Sustainable Development Goals (SDGs) and the World Health Organization's (WHO) Triple Billion Targets depends on informed decisions that are based on concerted data collection and monitoring efforts. Even though data availability has been increasing in recent years, significant gaps still remain for routine surveillance to guide policies and actions. The COVID-19 crisis has shown that more and better data and strengthened health information systems are needed to inform timely decisions that save lives. Traditional sources of data such as nationally representative surveys are not adequate for addressing this challenge alone. Additionally, the funding required to measure all health and well-being related SDG indicators and Triple Billion Targets using only traditional sources of data is a challenge to achieving efficient, timely and reliable monitoring systems. Citizen science, public participation in scientific research and knowledge production, can contribute to addressing some of these data gaps efficiently and sustainably when designed well, and ultimately, could contribute to the achievement of the health and well-being related SDGs and Triple Billion Targets. Through a systematic review of health and well-being related indicators, as well as citizen science initiatives, this paper aims to explore the potential of citizen science for monitoring health and well-being and for mobilizing action toward the achievement of health and well-being related targets as outlined in the SDG framework and Triple Billion Targets. The results demonstrate that out of 58 health and well-being related indicators of the SDGs and Triple Billion Targets covered in this study, citizen science could potentially contribute to monitoring 48 of these indicators and their targets, mostly at a local and community level, which can then be upscaled at a national level with the projection to reach global level monitoring and implementation. To integrate citizen science with official health and well-being statistics, the main recommendation is to build trusted partnerships with key stakeholders including National Statistical Offices, governments, academia and the custodian agencies, which is mostly the WHO for these health and well-being related targets and indicators.
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COVID-19 , Ciência do Cidadão , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Desenvolvimento Sustentável , Governo , Organização Mundial da SaúdeRESUMO
Multi-layer 2D material assemblies provide a great number of interfaces beneficial for electromagnetic wave absorption. However, avoiding agglomeration and achieving layer-by-layer ordered intercalation remain challenging. Here, 3D reduced graphene oxide (rGO)/MXene/TiO2/Fe2C lightweight porous microspheres with periodical intercalated structures and pronounced interfacial effects were constructed by spray-freeze-drying and microwave irradiation based on the Maxwell-Wagner effect. Such approach reinforced interfacial effects via defects introduction, porous skeleton, multi-layer assembly and multi-component system, leading to synergistic loss mechanisms. The abundant 2D/2D/0D/0D intercalated heterojunctions in the microspheres provide a high density of polarization charges while generating abundant polarization sites, resulting in boosted interfacial polarization, which is verified by CST Microwave Studio simulations. By precisely tuning the 2D nanosheets intercalation in the heterostructures, both the polarization loss and impedance matching improve significantly. At a low filler loading of 5 wt%, the polarization loss rate exceeds 70%, and a minimum reflection loss (RLmin) of -67.4 dB can be achieved. Moreover, radar cross-section simulations further confirm the attenuation ability of the optimized porous microspheres. These results not only provide novel insights into understanding and enhancing interfacial effects, but also constitute an attractive platform for implementing heterointerface engineering based on customized 2D hierarchical architectures.
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Background Reducing low birthweight (LBW, weight at birth less than 2,500g) prevalence by at least 30% between 2012 and 2025 is a target endorsed by the World Health Assembly that can contribute to achieving Sustainable Development Goal 2 (Zero Hunger) by 2030. The 2019 LBW estimates indicated a global prevalence of 14.6% (20.5 million newborns) in 2015. We aim to develop updated LBW estimates at global, regional, and national levels for up to 202 countries for the period of 2000 to 2020. Methods Two types of sources for LBW data will be sought: national administrative data and population-based surveys. Administrative data will be searched for countries with a facility birth rate ≥80% and included when birthweight data account for ≥80% of UN estimated live births for that country and year. Surveys with birthweight data published since release of the 2019 edition of the LBW estimates will be adjusted using the standard methodology applied for the previous estimates. Risk of bias assessments will be undertaken. Covariates will be selected based on a conceptual framework of plausible associations with LBW, covariate time-series data quality, collinearity between covariates and correlations with LBW. National LBW prevalence will be estimated using a Bayesian multilevel-mixed regression model, then aggregated to derive regional and global estimates through population-weighted averages. Conclusion Whilst availability of LBW data has increased, especially with more facility births, gaps remain in the quantity and quality of data, particularly in low-and middle-income countries. Challenges include high percentages of missing data, lack of adherence to reporting standards, inaccurate measurement, and data heaping. Updated LBW estimates are important to highlight the global burden of LBW, track progress towards nutrition targets, and inform investments in programmes. Reliable, nationally representative data are key, alongside investments to improve the measurement and recording of an accurate birthweight for every baby.
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The microwave properties of composites containing Fe-based ferromagnetic microwires and carbon fibres have been investigated as part of a campaign to bring added functionalities into structural composites. A transmission window observed in 1-6 GHz demonstrates double-negative (DNG), i.e., metamaterial characteristics in the composites containing short-cut carbon fibres and a parallel array of microwires; the metamaterial characteristic is due to the ferromagnetic resonance and a plasmonic behaviour, as short carbon fibres are proved to ameliorate DNG properties through enhancing the impedance of the composites. In parallel, magnetically tunable metamaterial features are realised in composites containing continuous carbon fibres and microwires, which can be switched on/off via rotating the electrical excitation direction. Such structural composites integrated with metamaterial features (termed as metacomposites) are potentially useful for active cloaking applications among others.
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BACKGROUND: Low birthweight (LBW) of less than 2500 g is an important marker of maternal and fetal health, predicting mortality, stunting, and adult-onset chronic conditions. Global nutrition targets set at the World Health Assembly in 2012 include an ambitious 30% reduction in LBW prevalence between 2012 and 2025. Estimates to track progress towards this target are lacking; with this analysis, we aim to assist in setting a baseline against which to assess progress towards the achievement of the World Health Assembly targets. METHODS: We sought to identify all available LBW input data for livebirths for the years 2000-16. We considered population-based national or nationally representative datasets for inclusion if they contained information on birthweight or LBW prevalence for livebirths. A new method for survey adjustment was developed and used. For 57 countries with higher quality time-series data, we smoothed country-reported trends in birthweight data by use of B-spline regression. For all other countries, we estimated LBW prevalence and trends by use of a restricted maximum likelihood approach with country-level random effects. Uncertainty ranges were obtained through bootstrapping. Results were summed at the regional and worldwide level. FINDINGS: We collated 1447 country-years of birthweight data (281 million births) for 148 countries of 195 UN member states (47 countries had no data meeting inclusion criteria). The estimated worldwide LBW prevalence in 2015 was 14·6% (uncertainty range [UR] 12·4-17·1) compared with 17·5% (14·1-21·3) in 2000 (average annual reduction rate [AARR] 1·23%). In 2015, an estimated 20·5 million (UR 17·4-24·0 million) livebirths were LBW, 91% from low-and-middle income countries, mainly southern Asia (48%) and sub-Saharan Africa (24%). INTERPRETATION: Although these estimates suggest some progress in reducing LBW between 2000 and 2015, achieving the 2·74% AARR required between 2012 and 2025 to meet the global nutrition target will require more than doubling progress, involving both improved measurement and programme investments to address the causes of LBW throughout the lifecycle. FUNDING: Bill & Melinda Gates Foundation, The Children's Investment Fund Foundation, United Nations Children's Fund (UNICEF), and WHO.
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Recém-Nascido de Baixo Peso , Distúrbios Nutricionais/prevenção & controle , Bases de Dados Factuais , Saúde Global , Inquéritos Epidemiológicos , Humanos , Funções Verossimilhança , Prevalência , Análise de RegressãoRESUMO
Interfaces remain one of the major issues in limiting the understanding and designing of polymer nanocomposites due to their complexity and pivotal role in determining the ultimate composites properties. In this study, we take multi-walled carbon nanotubes/silicone elastomer nanocomposites as a representative example, and have for the first time studied the correlation between high-frequency dielectric dispersion and static/dynamic interfacial characteristics. We have found that the interface together with other meso-structural parameters (volume fraction, dispersion, agglomeration) play decisive roles in formulating the dielectric patterns. The calculation of the relaxation times affords the relative importance of interfacial polarization to dipolar polarization in resultant dielectric relaxation. Dielectric measurements coupled with cyclic loading further reveals the remarkable capability of dielectric frequency dispersion in capturing the evolution of interfacial properties, such as a particular interface reconstruction process occurred to the surfactant-modified samples. All these results demonstrate that high-frequency dielectric spectroscopy is instrumental to probing both static and dynamic meso-structural characteristics, especially effective for the composites with relative weak interfaces which remains a mission impossible for many other techniques. The insights provided here based on the analyses of dielectric frequency dispersion will pave the way for optimized design and precise engineering of meso-structure in polymer nanocomposites.
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Resumen El conflicto armado en Colombia en el Siglo XXI no puede entenderse independientemente del Plan Colombia, en este sentido este acuerdo de cooperación se ha transformado, con sus pros y contras, en elemento central del conflicto en el país, abriendo la puerta a que haya un papel más activo de la comunidad internacional en el mismo. La cooperación militar internacional ha jugado un papel en el conflicto armado interno colombiano
Abstract The armed conflict in Colombia in the 21st century cannot be understood independently of the Colombia Plan. In this sense, this cooperation agreement has become, with its pros and cons, a key element of the conflict in the country, opening the door to have a more active role of the international community in it. International military cooperation has played a role in the Colombian internal armed conflict.