Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 80
Filtrar
1.
2.
Appetite ; 195: 107238, 2024 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-38331100

RESUMO

BACKGROUND: Many children consume a poor quality diet with only a third of children aged 6-9 years eating vegetables daily. A high quality diet is important for good health in childhood; however, the prevalence of children living with obesity has doubled from 10% to 23% during primary school in the UK. Cooking lessons have the potential to improve diet quality and reduce obesity prevalence in childhood, both of which are associated with improved cardiometabolic outcomes in adulthood. The aim of this systematic review is to investigate the impact of school-based cooking classes on cooking skills, food literacy and vegetable intake of children aged 4-12 years. METHODS: We conducted a systematic review of OVID Medline, OVID Embase, EBSCO CINHAL and EBSCO ERIC for comparative studies that evaluated outcomes of children receiving cooking classes compared to a control group. Interventions included contained food preparation or a cooking activities and took place on school premises. Risk of bias was assessed using ROB2 and Robins-I. Outcomes were pooled in a meta-analysis using a random-effects model using standardised mean differences or reviewed using narrative synthesis. Certainty of evidence was assessed using GRADE. RESULTS: We included 21 studies, (6 randomised). Meta-analysis showed a small positive effect on cooking self-efficacy of 0.39 units (95% CI 0.05 to 0.54), and a small positive effect on vegetable intake of 0.25 units (95% CI 0.05 to 0.45). Programmes with more than 6 h of cooking showed the greatest effects. CONCLUSIONS: Children's cooking programmes result in small improvements in cooking efficacy and vegetable intake, particularly those with more than 6 h of classes. It is recommended that future interventions use consistent measurement for children's food literacy and cooking confidence.


Assuntos
Frutas , Verduras , Criança , Humanos , Alfabetização , Culinária , Instituições Acadêmicas , Obesidade
3.
Resusc Plus ; 17: 100544, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38260121

RESUMO

Aims: The PARAMEDIC-3 trial evaluates the clinical and cost-effectiveness of an intraosseous first strategy, compared with an intravenous first strategy, for drug administration in adults who have sustained an out-of-hospital cardiac arrest. Methods: PARAMEDIC-3 is a pragmatic, allocation concealed, open-label, multi-centre, superiority randomised controlled trial. It will recruit 15,000 patients across English and Welsh ambulance services. Adults who have sustained an out-of-hospital cardiac arrest are individually randomised to an intraosseous access first strategy or intravenous access first strategy in a 1:1 ratio through an opaque, sealed envelope system. The randomised allocation determines the route used for the first two attempts at vascular access. Participants are initially enrolled under a deferred consent model.The primary clinical-effectiveness outcome is survival at 30-days. Secondary outcomes include return of spontaneous circulation, neurological functional outcome, and health-related quality of life. Participants are followed-up to six-months following cardiac arrest. The primary health economic outcome is incremental cost per quality-adjusted life year gained. Conclusion: The PARAMEDIC-3 trial will provide key information on the clinical and cost-effectiveness of drug route in out-of-hospital cardiac arrest.Trial registration: ISRCTN14223494, registered 16/08/2021, prospectively registered.

4.
Public Health Nutr ; 26(12): 3088-3099, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37727877

RESUMO

OBJECTIVE: To evaluate the impact of increased availability of healthier options on purchasing of different types of vending snack products sold in English leisure (sports) centres. DESIGN: An evaluation of an intervention using pre-post methods and interrupted time series analysis. Products within the vending machines were altered over three phases to increase the availability of healthier options, using agreed nutrition criteria - Government Buying Standards for Food and Catering Services (GBSF) for England - as a guide, as well as product availability. The primary outcome was the change in mean weekly purchased energy between the first and third phase. Secondary outcomes included changes by phase and by week in weekly number of purchases, fats, sugars and salt for all products combined and by individual product categories. SETTING: Fifteen sports centres in the city of Leeds, West Yorkshire, UK. PARTICIPANTS: Snack products sold in eighteen vending machines. RESULTS: Energy purchased reduced from baseline to phase 2, for all product categories combined, by 47·25 MJ (95 % CI (-61·22, -33·27)) per machine and by 279 kJ, (95 % CI (-325, -266)) per product unit. There were reductions in most nutrients purchased in all individual product categories except chocolate confectionery. Nutrients per product unit decreased for all product categories except saturated fat in chocolate confectionery. Minimal underlying trends in the baseline phase were identified, indicating changes in outcomes were likely to be due to the intervention. CONCLUSIONS: Introducing standards to increase availability of healthier snack products in vending machines is feasible without substantially affecting sales.


Assuntos
Preferências Alimentares , Lanches , Humanos , Estado Nutricional , Comércio , Inglaterra , Distribuidores Automáticos de Alimentos , Bebidas , Valor Nutritivo
5.
Digit Health ; 9: 20552076231187249, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37485332

RESUMO

Setting: The internet is an important source of health information but is unregulated. Little research has focused on the assessment of digital information related to nutrition. Aim: To develop and validate a novel online quality assessment tool (OQAT) for quality assessment of online nutrition information. Method: The OQAT was developed and validated in six distinct stages. After reviewing the literature, a framework and criteria were developed and formalised. Next, the quality assessment criteria were piloted on a subset of data and criteria refined. The established criteria were then validated against a previously validated assessment tool, and reliability was tested. Finally, the validated OQAT was used to assess the quality of articles from a 24-h collection period, 19 April 2021. Results: The final OQAT consisted of 10 key questions. Twenty-six news articles were assessed independently by two raters. Comparison of scores found moderate internal consistency (α = 0.382). Cohen's Kappa coefficient demonstrated high interrater agreement (k = 0.653, p < 0.001). The OQAT was tested on 291 relevant Uniform Resource Locators (URLs), which were determined to be either poor 3% (n = 9), satisfactory 49% (n = 144), or high-quality 48% (n = 139) articles. There was a statistically significant difference in OQAT scores between blogs, news articles, and press releases, χ2(2) = 23.22, p < 0.001, with a mean rank OQAT score of 138.2 for blogs, 216.6 for news articles, and 188.7 for press releases. Conclusion: This novel tool provides a reliable and objective method for assessing the quality of nutrition content online. It could potentially be used by researchers to assess the quality of online information in different settings and by organisations to inform readers of the quality of information being accessed.

6.
Int J Behav Nutr Phys Act ; 20(1): 29, 2023 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-36907879

RESUMO

BACKGROUND: Schools provide opportunities to improve the quality of children's diet, whilst reducing inequalities in childhood diet and health. Evidence supports whole school approaches, including consistency in food quality, eating culture and food education. However, such approaches are often poorly implemented due to the highly complex environments in which schools operate. We aimed to develop a school food systems map using a systems thinking approach to help identify the key factors influencing primary school children's dietary choice. METHODS: Eight workshops were conducted with 80 children (from schools from varying locations (region of England/UK; urban/rural), deprivation levels and prioritisation of school food policies)) and 11 workshops were held with 82 adult stakeholders across the UK (principals, teachers, caterers, school governors, parents, and local and voluntary sector organisations) to identify factors that influence food choice in children across a school day and their inter-relationships. Initial exploratory workshops started with a 'blank canvas' using a group model building approach. Later workshops consolidated findings and supported a wider discussion of factors, relationships and influences within the systems map. Strengths of the relationship between factors/nodes were agreed by stakeholders and individually depicted on the map. We facilitated an additional eight interactive, in-person workshops with children to map their activities across a whole school day to enable the production of a journey map which was shared with stakeholders in workshops to facilitate discussion. RESULTS: The final 'CONNECTS-Food' systems map included 202 factors that were grouped into 27 nodes. Thematic analysis identified four key themes: leadership and curriculum; child food preference; home environment; and school food environment. Network analysis highlighted key factors that influence child diet across a school day, which were largely in keeping with the thematic analysis; including: 'available funds/resources', 'awareness of initiatives and resources', 'child food preference and intake', 'eligibility of free school meals', 'family circumstances and eating behaviours', 'peer/social norms', 'priorities of head teachers and senior leaders'. CONCLUSIONS: Our systems map demonstrates the need to consider factors external to schools and their food environments. The map supports the identification of potential actions, interventions and policies to facilitate a systems-wide positive impact on children's diets.


Assuntos
Dieta , Instituições Acadêmicas , Criança , Adulto , Humanos , Alimentos , Comportamento Alimentar , Política Nutricional
7.
Proc Nutr Soc ; 82(3): 394-405, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36603858

RESUMO

Nutrition messages are a central part of policy making as well as communication via product information, advertising, healthcare advice and lifestyle campaigns. However, with amplified information (and misinformation) from a growing number of sources, inconsistent and conflicting food landscapes, and limited engagement from the public, nutrition messaging tensions have become more accentuated than previously. In this review, we focus on the challenges facing those wishing to effect dietary change through communication; and identify opportunities and future research questions. Beginning with a new working definition and taxonomy for the term 'nutrition message', we consider the evolution of public health nutrition messages from the past century and discuss which types of messages may be more effective. We then turn to the challenges of implementation and highlight specific barriers to recipients' understanding and change. While the evidence has many gaps and there is a need for systematic evaluation of nutrition messages, research indicates that recipients are more likely to act on fewer messages that provide clear benefits and which resonate with their perceived health needs, and which are relatively straightforward to implement. Effectiveness may be improved through consideration of how nutrition messages can be designed to complement key non-health drivers of food choice (taste, cost) and societal/cultural norms. Consistency can be achieved by aligning the wider food and messaging environment to desired public health actions; that is by ensuring that retail settings provide and signpost healthier choices, and that mass media nutrition messages work with, not against, public health advice.


Assuntos
Comunicação , Meios de Comunicação de Massa , Humanos , Alimentos , Estado Nutricional , Saúde Pública
8.
Front Nutr ; 9: 1046893, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36466407

RESUMO

[This corrects the article DOI: 10.3389/fnut.2022.893643.].

9.
Trials ; 23(1): 705, 2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-36002844

RESUMO

BACKGROUND: Many children would benefit from a diet richer in vegetables and fruit. 'Flavour School' is a programme of 'sensory food education', which aims to increase children's confidence and curiosity in exploring foods and flavours, especially vegetables and fruit. This study will conduct a cluster-randomised controlled trial to assess the outcomes of the Flavour School programme in primary school children aged 4-7 years. METHODS: Four hundred plus children from 4+ schools will either complete the Flavour School programme (experimental group) or have no intervention with normal school teaching (control group), cluster-randomised within-schools, by school class. Baseline data collection will consist of video recorded behavioural observation during a tasting activity, and post-intervention data collection will repeat this activity after the experimental group have completed the intervention. Process measures will be assessed using a teacher engagement feedback questionnaire. DISCUSSION: This study will provide causal data on the efficacy of a sensory food education intervention for increasing children's confidence and curiosity in exploring foods and flavours, especially vegetables and fruit. This new knowledge will help educators and policy makers to make evidence based decisions on uptake of sensory food education. TRIAL REGISTRATION: ISRCTN: 40249947 Date assigned 17 March 2020 Last edited 22 September 2021 Version 1.2 Trial Acronym OASES (Outcomes Assessment of Sensory Education in Schools).


Assuntos
Ingestão de Alimentos , Comportamento Exploratório , Frutas , Serviços de Saúde Escolar , Verduras , Criança , Pré-Escolar , Ingestão de Alimentos/psicologia , Humanos , Avaliação de Programas e Projetos de Saúde , Ensaios Clínicos Controlados Aleatórios como Assunto , Instituições Acadêmicas , Reino Unido
10.
Trials ; 23(1): 618, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35915460

RESUMO

BACKGROUND: Childhood obesity rates more than double during primary school in England. Acquiring competent cooking skills is a key part of children's education that can lead to improved knowledge of a healthy lifestyle and dietary behaviours. Evaluation of the impact of 'PhunkyFoods', a school-based food and nutrition education programme, will assess food literacy, cooking skills and dietary behaviour in primary-school children. METHODS: A cluster randomised controlled trial will be undertaken in 28 primary schools in North Yorkshire, UK, including a total population of children aged 7-9 years (n = 420). The trial has two arms: (a) the intervention group receiving PhunkyFoods programme (n = 210) and (b) the wait-list control group receiving the usual school curriculum (n = 210). The intervention 'PhunkyFoods' will be delivered by Purely Nutrition Ltd. The participating school staff are supported with training, policy development and access to resources to improve the delivery of nutrition education. Children participate through whole school assemblies, classroom activities, and after-school clubs about food preparation, cooking healthy meals and healthy living. Schools, parents and children have access to healthy meal recipes through the PhunkyFoods website. The primary outcomes are differences in food literacy and cooking skills scores between control and intervention arms after 12 months of the intervention and adjusted for baseline values. The secondary outcome is differences in fruit and vegetable intake between the arms after 12 months (adjusted for baseline). Treatment effects will be examined using mixed ANOVA and regression analysis. Primary analyses will adjust for baseline food literacy and cooking skills scores and secondary analysis will adjust for pre-specified baseline school and child level covariates. DISCUSSION: The PhunkyFoods programme is a flexible menu of options for schools to choose from, making this a highly complex intervention. Following Medical Research Council guidance, research perspectives will focus on effectiveness and theory-based approaches: to what extent the intervention produces the intended outcomes in real-world settings and what works in which circumstances. TRIAL REGISTRATION: ISRCTN ISRCTN68114155 . Prospectively registered on 22 October 2021.


Assuntos
Obesidade Infantil , Criança , Culinária , Promoção da Saúde , Humanos , Alfabetização , Obesidade Infantil/diagnóstico , Obesidade Infantil/epidemiologia , Obesidade Infantil/prevenção & controle , Serviços de Saúde Escolar , Instituições Acadêmicas , Reino Unido
11.
Front Nutr ; 9: 893643, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35795580

RESUMO

The taste of foods is a key factor for adolescents' food choices and intakes, yet, exploring taste characteristics of adolescents' diet is limited. Using food records for 284 adolescents (10-19 years old) from the National Diet and Nutrition Survey (NDNS), year 9 (2016-2017), we classified diets according to taste. Tastes for each food consumed were generated from a previous survey that asked participants to allocate one main taste to each food. Responses from that survey were processed and included in a Hierarchical Cluster Analysis (HCA) to identify taste clusters. The resulting tastes were then applied to the adolescents' food records in the NDNS. For each individual, the total weight of food per day for each taste was calculated. A linear regression model was used to explore dietary intakes from each taste. Findings reveal that adolescents' daily energy intake was highest (34%) from foods that taste sweet. Sweet foods were the main calorie contributors at breakfast and daytime snacking, while energy intake from neutral-tasting foods was higher at lunch and dinner. Sweet food intake was significantly positively associated with higher energy, sugar, and fat intakes. For each percentage increase in sweet foods, energy increased by 10 kcal/d (95% CI 6, 15; P < 0.01). Savory food intake was lower in carbohydrates and sugars; with neutral food consumption inversely associated with energy, carbohydrate, sugars, saturated and total fat. Higher salty food intake was linked to higher saturated fat as well as sodium consumption. Sweet and neutral foods dominate the UK adolescent diet, followed by savory tastes. Balancing the contributions of different tasting foods could assist in improving adolescent diet quality.

13.
Int J Yoga Therap ; 32(2022)2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35377949

RESUMO

There is a pressing need to identify non-opioid, evidence-based treatments to address the high prevalence of chronic pain in licensed opioid treatment programs (OTP). Yoga is an effective pain coping strategy but is not widely used by OTP patients. Few studies have examined underlying factors related to poor yoga utilization in this population. Seventy-one participants with and without chronic pain enrolled in a hospital-based OTP completed an acceptability survey assessing pain, current pain coping strategies, prior yoga experience, willingness to try yoga, and beliefs about yoga. Participants with and without chronic pain were compared, as were participants with and without prior yoga experience. The relationships between primary study variables in the chronic pain group were also explored. Participants reported using over-the-counter medications, meditation, stretching, and exercise to manage chronic pain, but yoga was not commonly used. Participants with prior yoga experience reported higher willingness to try yoga and more favorable beliefs about yoga than participants without prior yoga experience. There were no significant differences in willingness to try yoga between participants with and without chronic pain. Among participants with chronic pain, there was a positive association between total number of pain coping strategies used and willingness to try yoga. This study adds to the existing literature on the implementation of yoga programs into OTPs by demonstrating the acceptability of yoga in patients with opioid use disorder, including those experiencing chronic pain, and encourages additional research exploring implementation.


Assuntos
Dor Crônica , Meditação , Transtornos Relacionados ao Uso de Opioides , Yoga , Analgésicos Opioides/uso terapêutico , Dor Crônica/terapia , Humanos , Transtornos Relacionados ao Uso de Opioides/terapia
14.
Behav Brain Res ; 418: 113636, 2022 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-34687828

RESUMO

Early in instrumental learning, behavior is goal-directed and sensitive to changes in the value of the instrumental outcome. With sufficient repetition, responding becomes insensitive to changes in outcome value, or habitual. We have previously found that females transition into habit over a distinct range of training from 120 to 160 reinforced responses. This low level of instrumental training is markedly less than what has been shown to support habitual responding in male rats. To begin to investigate the early development of habit in females, we conducted a series of experiments in which we pretreated female rats with methamphetamine (METH) with the aim of sensitizing central dopamine, a major modulator of striatal function, prior to instrumental nose-poke training at the beginning and at the endpoint of the transition range in females. Following training, we tested for sensitivity to reinforcer devaluation (RD), which was conducted by repeatedly pairing reinforcers previously earned during training with lithium chloride (LiCl)-induced illness. As a counterpoint, a series of similar experiments was conducted separately in male rats. Additionally, in order to ascertain the validity of using nose-poke as an instrumental response, we compared sensitivity to devaluation between the Pavlovian approach towards the food magazine and the nose-poke response. In females, Vehicle groups responded in a habitual manner at both training levels (120 and 160 reinforced responses), whereas METH groups remained sensitive to devaluation. This suggests that increasing central dopamine delays habit formation in female rats. In male rats, Vehicle groups demonstrated goal-directed responding following training with 120 and 320 reinforced responses, and marginally goal-directed responding,with 160. METH-pretreated males were sensitive to devaluation at the 120 and 160 training levels, however, following more extended training to 320 reinforced responses, METH-pretreated males responded in a habitual manner, indicating that increasing central dopamine can advance habit formation in male rats. Overall, these results suggest that METH pretreatment maintains goal-directed responding in female rats when they are typically transitioning to habitual control of instrumental behavior and can advance habit formation in male rats given sufficient instrumental training. In addition, we found differential RD sensitivity of the nose-poke response used during instrumental training compared to Pavlovian approach towards the food magazine, confirming that there is a distinction between these two behaviors and that nose-poking is a valid instrumental response.


Assuntos
Comportamento Animal/efeitos dos fármacos , Condicionamento Operante , Dopamina/metabolismo , Hábitos , Metanfetamina/administração & dosagem , Reforço Psicológico , Animais , Comportamento Animal/fisiologia , Condicionamento Operante/efeitos dos fármacos , Condicionamento Operante/fisiologia , Corpo Estriado/metabolismo , Feminino , Masculino , Motivação , Ratos
15.
BMJ Open ; 11(2): e044205, 2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33622950

RESUMO

OBJECTIVES: The burden of childhood obesity is clustered among children in low-socioeconomic groups. Social spending on children-public welfare expenditure on families and education-may curb childhood obesity by reducing socioeconomic disadvantages. The objective of this study was to examine the relationship between social spending on children and childhood obesity across the Organisation for Economic Cooperation and Development (OECD) countries. DESIGN: Ecological study. SETTING: Data on social spending on children were obtained from the OECD Social Expenditure Database and the OECD educational finance indicators dataset during 2000-2015. Data on childhood obesity were obtained from the NCD Risk Factor Collaboration database. PARTICIPANTS: Aggregated statistics on obesity among children aged 5-19 years, estimated for OECD 35 countries based on the measured height and weight on 31.5 million children. OUTCOME MEASURES: Country-level prevalence of obesity among children aged 5-19 years. RESULTS: In cross-sectional analyses in 2015, social spending on children was inversely associated with the prevalence of childhood obesity after adjusting for potential confounders (the gross domestic product per capita, unemployment rate, poverty rate, percentage of children aged <20 years and prevalence of childhood obesity in 2000). In addition, when we focused on changes from 2000 to 2015, an average annual increase of US$100 in social spending per child was associated with a decrease in childhood obesity by 0.6 percentage points for girls (p=0.007) and 0.7 percentage points for boys (p=0.04) between 2000 and 2015, after adjusting for the potential confounders. The dimensions of social spending that contributed to these associations between the changes in social spending on children and childhood obesity were early childhood education and care (ECEC) and school education for girls and ECEC for boys. CONCLUSION: Countries that increase social spending on children tend to experience smaller increases in childhood obesity.


Assuntos
Organização para a Cooperação e Desenvolvimento Econômico , Obesidade Infantil , Adolescente , Adulto , Criança , Pré-Escolar , Estudos Transversais , Feminino , Produto Interno Bruto , Gastos em Saúde , Humanos , Masculino , Obesidade Infantil/epidemiologia , Adulto Jovem
16.
J Biomed Mater Res B Appl Biomater ; 109(9): 1271-1282, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33373104

RESUMO

Wound healing attempts to maintain homeostasis in the wound while minimizing the risk of infection to the tissue by foreign agents, such as opportunistic bacterial pathogens. Biofilms established by these pathogens are a common cause of chronic infections that slow the healing process. Preparation of skin wound healing devices comprised of electrospun proteins associated with skin have been shown to accelerate the healing process relative to conventional wound dressings. In this work, we have developed electrospinning methods to incorporate the antimicrobial ionic liquid/deep eutectic solvent choline geranate (CAGE) into these devices. Integration of CAGE into the dressing material was verified via 1 H nuclear magnetic resonance spectrometry, and the effect on the material property of the resultant devices were assessed using scanning electron microscopy. CAGE-containing devices demonstrate a concentration-dependent inactivation of exogenously applied solutions of both gram-positive and gram-negative pathogens (Enterococcus sp and Pseudomonas aeruginosa, respectively), but maintain their ability to serve as a compatible platform for proliferation of human dermal neonatal fibroblasts.


Assuntos
Anti-Infecciosos/química , Materiais Biocompatíveis/química , Colina/química , Infecção Persistente/tratamento farmacológico , Pseudomonas aeruginosa/efeitos dos fármacos , Alicerces Teciduais/química , Cicatrização/efeitos dos fármacos , Administração Cutânea , Anti-Infecciosos/farmacologia , Bandagens , Biofilmes , Colina/farmacologia , Reagentes de Ligações Cruzadas/química , Liberação Controlada de Fármacos , Fibroblastos/química , Humanos , Líquidos Iônicos/química , Testes de Sensibilidade Microbiana , Pele , Engenharia Tecidual
17.
ACS Nano ; 14(12): 17535-17542, 2020 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-33270432

RESUMO

Plasmonic-based photodetectors are receiving increased attention because simple structural changes can make the photodetectors spectrally sensitive. In this study, asymmetric gold nanostructures are used as simple structures for photodetection via the photothermoelectric response. These single metal photodetectors use localized optical absorption from plasmon resonances of gold nanowires at desired wavelengths to generate temperature gradients. Combined with a geometry-dependent Seebeck coefficient, the result is a net electrical signal when the whole geometry is illuminated, with spectral sensitivity and polarization dependence from the plasmon resonances. We show experimental results and simulations of single-wavelength photodetectors at two wavelengths in the near IR range: 785 and 1060 nm. Based on simulation results and a model for the geometry-dependent Seebeck response, we demonstrate a photodetector structure that generates polarization-sensitive responses of opposite signs for the two wavelengths. The experimental photothermoelectric results are combined with simulations to infer the geometry dependence of the Seebeck response. These results can be used to increase the responsivity of these photodetectors further.

18.
Proc Natl Acad Sci U S A ; 117(38): 23350-23355, 2020 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-32900922

RESUMO

The electronic Seebeck response in a conductor involves the energy-dependent mean free path of the charge carriers and is affected by crystal structure, scattering from boundaries and defects, and strain. Previous photothermoelectric (PTE) studies have suggested that the thermoelectric properties of polycrystalline metal nanowires are related to grain structure, although direct evidence linking crystal microstructure to the PTE response is difficult to elucidate. Here, we show that room temperature scanning PTE measurements are sensitive probes that can detect subtle changes in the local Seebeck coefficient of gold tied to the underlying defects and strain that mediate crystal deformation. This connection is revealed through a combination of scanning PTE and electron microscopy measurements of single-crystal and bicrystal gold microscale devices. Unexpectedly, the photovoltage maps strongly correlate with gradually varying crystallographic misorientations detected by electron backscatter diffraction. The effects of individual grain boundaries and differing grain orientations on the PTE signal are minimal. This scanning PTE technique shows promise for identifying minor structural distortions in nanoscale materials and devices.

20.
Sci Rep ; 10(1): 12929, 2020 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-32737349

RESUMO

Obesity is one of the leading causes of preventable deaths. Development of satiety-enhancing foods is considered as a promising strategy to reduce food intake and promote weight management. Food texture may influence satiety through differences in appetite sensations, gastrointestinal peptide release and food intake, but the degree to which it does remains unclear. Herein, we report the first systematic review and meta-analyses on effects of food texture (form, viscosity, structural complexity) on satiety. Both solid and higher viscous food reduce hunger by - 4.97 mm (95% confidence interval (CI) - 8.13, - 1.80) and - 2.10 mm (95% CI - 4.38, 1.18), respectively compared to liquid and low viscous food. An effect of viscosity on fullness (95% CI 5.20 (2.43, 7.97) and a moderate effect of the form of food (95% CI - 26.19 (- 61.72, - 9.35) on food intake were noted. Due to the large variation among studies, the results should be interpreted cautiously and modestly.


Assuntos
Ingestão de Alimentos , Ingestão de Energia , Alimentos , Resposta de Saciedade , Humanos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...