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1.
Materials (Basel) ; 17(3)2024 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-38591605

RESUMEN

Wire-arc additive manufacturing (WAAM) is a promising industrial production technique. Without optimization, inherent temperature gradients can cause powerful residual stresses and microstructural defects. There is therefore a need for data-driven methods allowing real-time process optimization for WAAM. This study focuses on machine learning (ML)-based prediction of temperature history for WAAM-produced aluminum bars with different geometries and process parameters, including bar length, number of deposition layers, and heat source movement speed. Finite element (FE) simulations are used to provide training and prediction data. The ML models are based on a simple multilayer perceptron (MLP) and performed well during baseline training and testing, giving a testing mean absolute percentage error (MAPE) of less than 0.7% with an 80/20 train-test split, with low variation in model performance. When using the trained models to predict results from FE simulations with greater length or number of layers, the MAPE increased to an average of 3.22% or less, with greater variability. In the cases of greatest difference, some models still returned a MAPE of less than 1%. For different scanning speeds, the performance was worse, with some outlier models giving a MAPE of up to 14.91%. This study demonstrates the transferability of temperature history for WAAM with a simple MLP approach.

2.
Food Res Int ; 162(Pt A): 111994, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36461300

RESUMEN

Extensive work has established the importance of the gut microbiota during the first years of life. However, there are few longitudinal studies describing the role of infants' diet on the evolution of the fecal microbiota and their metabolic activity during this stage. The aim of this work was to explore the impact of diet on the composition of the major intestinal microorganisms and their main microbial metabolites from birth to 12 months. This is a longitudinal prospective study of diet and fecal microbiota. Bacterial groups levels were determined by qPCR and short-chain fatty acids (SCFAs) concentrations by gas chromatography. Information from self-administered questionnaires about general characteristics and food frequency were obtained from a cohort of 83, Spanish and full-term, infants at 15, 90, 180 and 365 days of age. Results revealed that Enterobacteriaceae decrease in weaning period contrary to Bacteroides group and Clostridium cluster IV. CONCLUSION: our study supports weaning period as a key step for gut microbiota transition and suggests the importance of the consumption of dietary fiber with the increase of certain bacterial groups as Clostridium cluster IV, which could be beneficial for the host. Finally, studies specially designed to analyze the production and the excretion of SCFAs in children are needed to understand how diet could influence in this process.


Asunto(s)
Dieta , Microbiota , Niño , Lactante , Humanos , Estudios Prospectivos , Heces , Fibras de la Dieta
3.
Nutrients ; 14(8)2022 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-35458226

RESUMEN

The first years of life represent a window of opportunity to establish proper dietary patterns and to maintain them over time. Our aim was to describe the diet of a cohort of Spanish children, from 2 to 36 months, and to identify the components that could influence the quality of the diet at 24 and 36 months of age. This was a longitudinal prospective study analyzing information from administered questionnaires about general characteristics and food frequency consumption in 97 full-term babies. At 2-3 months of age, only 53.6% of infants were observed to be breastfed. The intake of animal foodstuffs from 12 to 36 months was higher than national recommendations, and the contrary was true for fruits and vegetables. The intake of vitamin D was below European Food Safety Authority recommendations. Moreover, energy intake at 6 months was inversely associated with Mediterranean Diet Score (MDS) at 24 months, whereas vegetables intake was positively associated with MDS at 36 months. These results could be useful in the creation of future guidelines focused on the promotion of breastfeeding and healthy early-life food habits.


Asunto(s)
Dieta Mediterránea , Animales , Lactancia Materna , Dieta , Conducta Alimentaria , Femenino , Humanos , Lactante , Fenómenos Fisiológicos Nutricionales del Lactante , Estudios Prospectivos
4.
Nutrients ; 13(3)2021 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-33803743

RESUMEN

Ensuring the nutritional demands of preterm (PT) infants during complementary feeding could contribute significantly to the infants' long-term health and development. However, the dietary guidelines for complementary feeding in PT are scarce. Thus, describing dietary intake and identifying nutritional targets for these infants could be of great interest. The aim of this study is to assess the food intake and anthropometric parameters in a Mediterranean infant cohort from 6 to 24 months and to identify nutritional targets especially focused on late preterm infants. This is a longitudinal prospective study analyzing information from administered questionnaires about general characteristics and food frequency consumption in 115 infants (20 PT (32 to 36 gestational weeks), 95 full-term (FT)) at 6, 12 and 24 months of age. Results show that the differences in the prevalence of underweight observed in PT infants vs. FT infants are maintained for up to 6 months of age but disappear at 12 and 24 months. The age of inclusion of new foods and the average intake of the main food groups was not different from that of FTs. Although protein intake at 6 months was directly correlated with weight gain and growth in FT, these associations were not observed in PT. At the nutritional level, the low intake of vitamin D in preterm infants is noteworthy. These findings may be useful when designing new intervention strategies for this population group.


Asunto(s)
Antropometría , Dieta/estadística & datos numéricos , Fenómenos Fisiológicos Nutricionales del Lactante/fisiología , Recien Nacido Prematuro/crecimiento & desarrollo , Delgadez/epidemiología , Dieta/efectos adversos , Encuestas sobre Dietas , Ingestión de Alimentos , Femenino , Edad Gestacional , Humanos , Lactante , Recién Nacido , Estudios Longitudinales , Masculino , Región Mediterránea/epidemiología , Política Nutricional , Prevalencia , Estudios Prospectivos , Delgadez/etiología , Aumento de Peso
5.
Ther Innov Regul Sci ; 54(5): 978-987, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-31933181

RESUMEN

BACKGROUND: Clinical research sites conduct trials with diverse complexities, timelines, and ever-changing workloads. Though the principal investigator (PI) is ultimately responsible for the content and conduct of trials, they rely heavily on site staff to successfully enroll and complete studies following good clinical practice (GCP) Guidelines. The mainstays of the site workforce are the clinical research coordinators (CRCs) to whom the trials are assigned. These CRCs work on many studies concurrently. Managing study assignments and workload is a difficult task that requires knowledge of the trial complexity, expected enrollment, and many other factors affecting performance. METHODS: Traditional methods for allocating workload to site staff quantitate trial complexity and estimate work hours by factoring in the number of trial participants. However, this does not account for the effects of associated workload or variability in staff attributes. It also neglects other factors that affect performance and assumes maximum enrollment and completion of the trial by all participants. This article introduces a novel approach that determines the effects of protocol complexity on CRC productivity without effort tracking. These metrics permit an assessment of how the CRC's performance is affected by the number of studies assigned. RESULTS: By understanding the effects of workload allocation on CRC productivity and capacity, the site manager can use an algorithmic approach toward improving performance. The process takes into account factors that are both within and outside the control of the site manager. CONCLUSION: Sites may benefit from analytics that measures how CRCs adapt to the effects of study complexity on cumulative workloads over time. Optimizing productivity also means conforming to GCP Guidelines and avoiding staff burnout. As studies become increasingly difficult, site managers need tools to manage complexity and balance workloads among staff.


Asunto(s)
Eficiencia , Carga de Trabajo , Humanos , Investigadores
6.
Ther Innov Regul Sci ; 53(1): 52-58, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-29714592

RESUMEN

BACKGROUND: Research coordinators (or teams) are usually assigned to multiple studies of varying complexity at any one time, each with different and ever-changing workloads. As a result, determining the impact of protocol complexity on productivity is not easily accomplished. Standard methods of effort tracking typically require oversight or create additional workload to the site staff under study; they are time-consuming, expensive, intrusive, and usually incomplete. METHODS: This article describes a novel method for determining the impact of protocol complexity on clinical research coordinator (CRC) or team productivity by using proxy variables in place of effort tracking. A protocol assessment tool that quantitates complexity is used to determine cumulative workload. RESULTS: Productivity graphs are generated for each CRC per month and can be followed over time to assess trends or for comparative analysis. CONCLUSION: The data provide managers with unique insights into the functional capacity of study coordinators and support staff. The goal is to optimize efficiency by applying a systematic decision process from performance and productivity trends. In addition to exploring the theory behind the method, this article begins a discussion on the use of this information in clinical research site management.


Asunto(s)
Eficiencia , Investigadores , Carga de Trabajo , Protocolos Clínicos , Humanos
7.
PhytoKeys ; (98): 15-50, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29750070

RESUMEN

Boechera is a model genus that is of particular interest for understanding apomixis due to the presence of numerous apomictic diploid lineages that are tightly correlated with hybridisation events. Boechera includes many narrowly distributed endemics and apomictic hybrid lineages that obscure morphological boundaries amongst taxa. In this study, we focus on the Boechera suffrutescens complex, a phylogenetically well-supported but taxonomically complex north-western United States clade whose diploid species currently include the widespread B. suffrutescens and two narrowly distributed serpentine endemics, B. constancei and B. rollei. Using a 15-locus microsatellite dataset, we infer ploidy and sexual vs. apomictic reproduction for all individuals and then assess species limits for all sexual diploid samples. Our results support the recognition of B. rollei and B. constancei as distinct species and reveal three divergent sexual diploid lineages within B. suffrutescens sensu lato. The latter three lineages exhibit geographic, genetic and morphological coherence and consequently warrant recognition at the species rank. These include Boechera suffrutescens s.s., which is restricted to Idaho and eastern Oregon, Boechera botulifructa, a newly described species distributed along the Cascade Mountain Province from Lassen County, California north to Deschutes County, Oregon and the heretofore dismissed species Boechera duriuscula (basionym ≡ Arabis duriuscula), which occurs along the Sierra Nevada Province from Plumas County southwards to Fresno County, California. Our data also reveal substructure in B. constancei that is likely attributable to the highly fragmented distribution of its serpentine habitat. This refined taxonomic framework for the B. suffrutescens complex enhances Boechera as a model system, adds to our knowledge of speciation in edaphically extreme environments and provides information on ongoing conservation efforts for these taxa.

8.
J Appl Physiol (1985) ; 124(2): 330-340, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-28935827

RESUMEN

Szymanski MC, Gillum TL, Gould LM, Morin DS, Kuennen MR. Short-term dietary curcumin supplementation reduces gastrointestinal barrier damage and physiological strain responses during exertional heat stress. J Appl Physiol 124: 330-340, 2018. First published September 21, 2017; doi: 10.1152/japplphysiol.00515.2017 .-This work investigated the effect of 3 days of 500 mg/day dietary curcumin supplementation on gastrointestinal barrier damage and systems-physiology responses to exertional heat stress in non-heat-acclimated humans. Eight participants ran (65% V̇o2max) for 60 min in a Darwin chamber (37°C/25% relative humidity) two times (Curcumin/Placebo). Intestinal fatty acid-binding protein (I-FABP) and associated proinflammatory [monocyte chemoattractant protein-1, tumor necrosis factor-α (TNF-α), interleukin-6] and anti-inflammatory [interleukin-1 receptor antagonist (IL-1RA), interleukin-10 (IL-10)] cytokines were assayed from plasma collected before (Pre), after (Post) and 1 (1-Post) and 4 (4-Post) h after exercise. Core temperature and HR were measured throughout exercise; the physiological strain index (PSI) was calculated from these variables. Condition differences were determined with 2-way (condition × time) repeated-measures ANOVAs. The interaction of condition × time was significant ( P = 0.05) for I-FABP and IL-1RA. Post hoc analysis indicated I-FABP increased more from Pre to Post (87%) and 1-Post (33%) in Placebo than in Curcumin (58 and 18%, respectively). IL-1RA increased more from Pre to 1-Post in Placebo (153%) than in Curcumin (77%). TNF-α increased ( P = 0.01) from Pre to Post (19%) and 1-Post (24%) in Placebo but not in Curcumin ( P > 0.05). IL-10 increased ( P < 0.01) from Pre to Post (61%) and 1-Post (42%) in Placebo not in Curcumin ( P > 0.05). The PSI, which indicates exertional heatstroke risk, was also lower ( P < 0.01) in Curcumin than Placebo from 40 to 60 min of exercise. These data suggest 3 days curcumin supplementation may improve gastrointestinal function, associated cytokines, and systems-level physiology responses during exertional heat stress. This could help reduce exertional heatstroke risk in non-heat-acclimated individuals. NEW & NOTEWORTHY Exercise-heat stress increases gastrointestinal barrier damage and risk of exertional heatstroke. Over the past decade at least eight different dietary supplements have been tested for potential improvements in gastrointestinal barrier function and systems-level physiology responses during exercise-heat stress. None have been shown to protect against both insults simultaneously. In this report 3 days of 500 mg/day dietary curcumin supplementation are shown to improve gastrointestinal barrier function, associated cytokine responses, and systems-level physiology parameters. Further research is warranted.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Curcumina/uso terapéutico , Citocinas/sangre , Trastornos de Estrés por Calor/tratamiento farmacológico , Mucosa Intestinal/efectos de los fármacos , Adolescente , Antiinflamatorios no Esteroideos/farmacología , Biomarcadores/sangre , Temperatura Corporal/efectos de los fármacos , Curcumina/farmacología , Dieta , Suplementos Dietéticos , Proteínas de Unión a Ácidos Grasos/sangre , Femenino , Humanos , Masculino , Estado de Hidratación del Organismo , Consumo de Oxígeno/efectos de los fármacos , Fitoterapia , Adulto Joven
9.
Int J Med Inform ; 91: 67-73, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27185510

RESUMEN

OBJECTIVES: This paper has two objectives. First, it categorizes the Twitter handles tweeted flu related information based on the amount of replies and mentions within the Twitter network. The collected Twitter accounts are categorized as media, health related individuals, organizations, government, individuals with no background with media or medical field, in order to test the relationship between centrality measures of the accounts and their categories. The second objective is to examine the relationship between the importance of the Twitter accounts in the network, centrality measures, and specific characteristics of each account, including the number of tweets and followers as well as the number of accounts followed and liked. METHODS: Using Twitter search network API, tweets with "flu" keyword were collected and tabulated. Network centralities were calculated with network analysis tool, NodeXL. The collected Twitters accounts were content analyzed and categorized by multiple coders. RESULTS: When the media or organizational Twitter accounts were present in the list of important Twitter accounts, they were highly effective disseminating flu-related information. Also, they were more likely to stay active one year after the data collection period compared to other influential individual accounts. CONCLUSIONS: Health campaigns are recommended to focus on recruiting influential Twitter accounts and encouraging them to retweet or mention in order to produce better results in disseminating information. Although some individual social media users were valuable assets in terms of spreading information about flu, media and organization handles were more reliable information distributors. Thus, health information practitioners are advised to design health campaigns better utilizing media and organizations rather than individuals to achieve consistent and efficient campaign outcomes.


Asunto(s)
Promoción de la Salud/métodos , Difusión de la Información/métodos , Medios de Comunicación Sociales/organización & administración , Centers for Disease Control and Prevention, U.S. , Promoción de la Salud/organización & administración , Promoción de la Salud/normas , Humanos , Gripe Humana/epidemiología , Salud Pública/métodos , Administración en Salud Pública , Medios de Comunicación Sociales/tendencias , Estados Unidos/epidemiología , Organización Mundial de la Salud
10.
J Health Commun ; 20(12): 1382-90, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26496676

RESUMEN

Past research has examined portrayals of risk behavior in various media, including television, advertising, and film. To address an underexplored area, this study analyzed drinking, smoking, and sexual activities in MTV reality programming popular among adolescent viewers from 2004 to 2011. Cast members' demographic attributes were also examined in relation to their risk behaviors. Results demonstrated that drinking and casual sexual behaviors were pervasive among cast members. Smoking and more intense sexual behaviors were also present, but to a smaller degree. Men and young adult cast members were more likely to engage in risk behaviors than women and teenage cast members. Also, ethnic/racial minority characters were shown drinking more often than were White cast members. Interpretations of these findings are discussed based in social cognitive theory and the concept of super peers. Implications for future research are provided.


Asunto(s)
Consumo de Bebidas Alcohólicas/psicología , Conductas Relacionadas con la Salud , Asunción de Riesgos , Conducta Sexual/psicología , Fumar/psicología , Televisión/estadística & datos numéricos , Adolescente , Factores de Edad , Consumo de Bebidas Alcohólicas/etnología , Etnicidad/psicología , Etnicidad/estadística & datos numéricos , Femenino , Humanos , Masculino , Grupos Minoritarios/psicología , Grupos Minoritarios/estadística & datos numéricos , Grupo Paritario , Factores Sexuales , Conducta Sexual/etnología , Fumar/etnología , Teoría Social , Adulto Joven
11.
J Strength Cond Res ; 28(4): 958-63, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24104542

RESUMEN

Competitive swimmers regularly perform apnea series with or without fins as part of their training, but the ergogenic and metabolic repercussions of acute and chronic apnea have not been examined. Therefore, we aimed to investigate the cardiovascular, lactate, arterial oxygen saturation and hormonal responses to acute apnea in relation to performance in male swimmers. According to a randomized protocol, 15 national or regional competitive swimmers were monitored while performing four 100-m freestyle trials, each consisting of four 25-m segments with departure every 30 seconds at maximal speed in the following conditions: with normal frequency breathing with fins (F) and without fins (S) and with complete apnea for the four 25-m segments with (FAp) and without fins (SAp). Heart rate (HR) was measured continuously and arterial oxygen saturation, blood, and saliva samples were assessed after 30 seconds, 3 minutes, and 10 minutes of recovery, respectively. Swimming performance was better with fins than without both with normal frequency breathing and apnea (p < 0.001). Apnea induced no change in lactatemia, but a decrease in arterial oxygen saturation in both SAp and FAp (p < 0.001) was noted and a decrease in HR and swimming performance in SAp (p < 0.01). During apnea without fins, performance alteration was correlated with bradycardia (r = 0.63) and arterial oxygen desaturation (r = -0.57). Saliva dehydroepiandrosterone was increased compared with basal values whatever the trial (p ≤ 0.05), whereas no change was found in saliva cortisol or testosterone. Further studies are necessary to clarify the fin effect on HR and performance during apnea swimming.


Asunto(s)
Apnea/fisiopatología , Rendimiento Atlético/fisiología , Lactatos/sangre , Consumo de Oxígeno/fisiología , Natación/fisiología , Enfermedad Aguda , Análisis de Varianza , Atletas , Deshidroepiandrosterona/análisis , Ensayo de Inmunoadsorción Enzimática , Frecuencia Cardíaca/fisiología , Humanos , Hidrocortisona/metabolismo , Masculino , Oximetría , Educación y Entrenamiento Físico/métodos , Medición de Riesgo , Testosterona/análisis , Factores de Tiempo , Adulto Joven
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