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1.
Appl Environ Microbiol ; 89(10): e0103423, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37728921

RESUMO

The genus Periweissella was proposed as a novel genus in the Lactobacillaceae in 2022. However, the phylogenetic relationship between Periweissella and other heterofermentative lactobacilli, and the genetic and physiological properties of this genus remain unclear. This study aimed to determine the phylogenetic relationship between Periweissella and the two closest genera, Weissella and Furfurilactobacillus, by the phylogenetic analysis and calculation of (core gene) pairwise average amino acid identity. Targeted genomic analysis showed that fructose bisphosphate aldolase was only present in the genome of Pw. cryptocerci. Mannitol dehydrogenase was found in genomes of Pw. beninensis, Pw. fabaria, and Pw. fabalis. Untargeted genomic analysis identified the presence of flagellar genes in Periweissella but not in other closely related genera. Phenotypes related to carbohydrate fermentation and motility matched the genotypes. Motility genes were organized in a single operon and the proteins shared a high amino acid similarity in the genus Periweissella. The relatively low similarity of motility operons between Periweissella and other motile lactobacilli indicated the acquisition of motility by the ancestral species. Our findings facilitate the phylogenetic, genetic, and phenotypic understanding of the genus Periweissella.ImportanceThe genus Periweissella is a heterofermentative genus in the Lactobacillaceae which includes predominantly isolates from cocoa fermentations in tropical climates. Despite the relevance of the genus in food fermentations, genetic and physiological properties of the genus are poorly characterized and genome sequences became available only after 2020. This study characterized strains of the genus by functional genomic analysis, and by determination of metabolic and physiological traits. Phylogenetic analysis revealed that Periweissella is the evolutionary link between rod-shaped heterofermentative lactobacilli and the coccoid Leuconostoc clade with the genera Weissella and Furfurilactobacillus as closest relatives. Periweissella is the only heterofermentative genus in the Lactobacillaceae which comprises predominantly motile strains. The genomic, physiological, and metabolic characterization of Periweissella may facilitate the potential use of strains of the genus as starter culture in traditional or novel food fermentations.


Assuntos
Lactobacillaceae , Weissella , Filogenia , Lactobacillaceae/metabolismo , Lactobacillus/genética , Weissella/genética , Weissella/metabolismo , Genômica , Aminoácidos/metabolismo , Fermentação , RNA Ribossômico 16S/genética
2.
Am J Obstet Gynecol ; 229(2): 158.e1-158.e14, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36758710

RESUMO

BACKGROUND: Preconception lifestyle intervention holds potential for reducing gestational diabetes mellitus, but clinical trial data are lacking. OBJECTIVE: This study aimed to determine the effects of a prepregnancy weight loss intervention on gestational diabetes mellitus recurrence in women with overweight/obesity and previous gestational diabetes mellitus. STUDY DESIGN: A 2-site, randomized controlled trial comparing a prepregnancy lifestyle intervention with educational control was conducted between December 2017 and February 2022. A total of 199 English- and Spanish-speaking adults with overweight/obesity and previous gestational diabetes mellitus were randomized to a 16-week prepregnancy lifestyle intervention with ongoing treatment until conception or educational control. The primary outcome was gestational diabetes mellitus recurrence. Analyses excluded 6 participants who conceived but did not have gestational diabetes mellitus ascertained by standard methods. RESULTS: In the 63 (33%) women who conceived and had gestational diabetes mellitus ascertained (Ns=38/102 [37%] intervention vs 25/91 [28.0%] control; P=.17), those in the intervention group had significantly greater weight loss at 16 weeks compared with controls (4.8 [3.4-6.0] vs 0.7 [-0.9 to 2.3] kg; P=.001) and a greater proportion lost ≥5% of body weight (50.0% [17/34] vs 13.6% [3/22]; P=.005). There was no significant difference in the incidence of gestational diabetes mellitus recurrence between the intervention (57.9% [ns=23/38]) and the control group (44.0% [ns=11/25]; odds ratio, 1.8 [0.59-5.8]). Independent of group, greater prepregnancy weight loss predicted 21% lower odds of gestational diabetes mellitus recurrence (odds ratio, 0.79 [0.66-0.94]; P=.008). A ≥5% weight loss before conception reduced the odds of gestational diabetes mellitus recurrence by 82% (odds ratio, 0.18 [0.04-0.88]; P=.03). CONCLUSION: Lifestyle intervention produced considerable prepregnancy weight loss but did not affect gestational diabetes mellitus rates. Given that the conception rate was 50% lower than expected, this study was underpowered.


Assuntos
Diabetes Gestacional , Gravidez , Adulto , Feminino , Humanos , Masculino , Diabetes Gestacional/prevenção & controle , Sobrepeso/terapia , Período Pós-Parto , Obesidade/epidemiologia , Obesidade/terapia , Estilo de Vida , Redução de Peso
3.
Prog Community Health Partnersh ; 17(4): 699-710, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38286784

RESUMO

BACKGROUND: Community-based participatory research (CBPR) is an increasingly recognized approach to address health inequities. Although in CBPR all processes occur within the community context, its diagrammatic model places the intervention/research outside of the community rather than conceptualizing it as an event in a complex web of system components. OBJECTIVES: We sought to 1) introduce a systems-oriented community ownership conceptual framework that integrates a systems perspective with CBPR and 2) to describe an application of this framework in the form of the Mi Gente, Nuestra Salud initiative, a research-based, action-oriented collaboration between Cal Poly investigators and community partners in Santa Maria and Guadalupe, California. METHODS: We conducted a stocktake of community assets and partnerships in Santa Maria and Guadalupe, among California's poorest and most medically underserved cities; created marketing materials; launched the initiative in December 2020; and collected survey and interview data on community health concerns. An advisory board guides direction of the work. Activities are intended to affect partnerships (who is involved in actions and decisions) and processes (what actions will be taken), as well as resources (e.g., building human and social capital by changing narratives of local, historically rooted power dynamics and offering peer learning opportunities on advocacy and health care interactions). Implementation challenges within this framework are also discussed. CONCLUSIONS: By de-centering specific interventions and conceptualizing them as single events in a complex web, our system-oriented community ownership model brings the focus back to the system itself, and to system-based processes and solutions, while still guided by CBPR principles.


Assuntos
Pesquisa Participativa Baseada na Comunidade , Propriedade , Humanos , Pesquisa Participativa Baseada na Comunidade/métodos , Inquéritos e Questionários
4.
An. Fac. Cienc. Méd. (Asunción) ; 55(3): 99-104, 20221115.
Artigo em Espanhol | LILACS | ID: biblio-1401559

RESUMO

Introducción: Uno de los tratamientos indicados para la deficiencia maxilar transversal es la expansión maxilar rápida (REM). El presente artículo trata sobre la terapia REM y muestra, a partir de una revisión bibliográfica, los diversos beneficios que esta puede brindar al paciente y los cambios que puede generar en su anatomía. Objetivos: Abordar el efecto de la terapia REM sobre la vía aérea nasofaríngea. También describir, en base a evidencia científica, los cambios que produce en la morfología y resistencia sobre la vía aérea faríngea. Esto mediante distintos métodos de estudios disponibles actualmente. Materiales y métodos: Se realizó una búsqueda bibliográfica en las bases de datos: PubMed, Clinicalkey y Epistemonikos. Se seleccionaron trabajos publicados en los últimos 8 años en adelante. De un universo total de 77 publicaciones, fueron seleccionados 12 estudios para esta revisión. Se excluyeron estudios en los cuales se realizaban acciones clínicas que escapan al tratamiento ortopédico. También se excluyeron tratamientos realizados para mejorar la vía aérea, basados en el tratamiento ortopédico del crecimiento mandibular. Resultados: En los estudios realizados mediante radiografías cefalométricas se obtuvo un aumento significativo (p <0.05) en el espacio de la vía aérea nasofaríngea, en particular en las medidas AD2 y AD-PtV, después del tratamiento ortodóncico. Por otro lado, AD1 también aumentó, pero no significativamente (p> 0.05). Conclusión: La terapia REM, en pacientes en crecimiento, logra separar la sutura palatina media aumentando el tamaño del piso de las fosas nasales y el volumen en el territorio nasofaríngeo. Se necesitan estudios con un tamaño de muestra mayor y un seguimiento a largo plazo para establecer el éxito de esta terapia.


Introduction: One of the treatments indicated for transverse maxillary deficiency is rapid maxillary expansion (REM). This article deals with REM therapy and shows, based on a bibliographic review, the various benefits that it can generate for the patient and the changes in their anatomy. Objectives: To elucidate the effect of REM therapy on the nasopharyngeal airway. Also expose, based on scientific evidence, the changes that it produces in the morphology and resistance on the pharyngeal airway. This through different study methods currently available. Materials and methods: A bibliographic search was carried out in the databases: PubMed, Clinicalkey and Epistemonikos. From a total universe of 77 publications, 12 studies were selected for this review. Results: In the studies carried out using cephalometric radiographs, a significant increase (p < 0.05) in the nasopharyngeal airway space was obtained, particularly in the AD2 and AD-PtV measurements, after orthodontic treatment. On the other hand, AD1 also increased, but not significantly (p > 0.05). Conclusion: REM therapy, in growing patients, manages to separate the middle palatal suture by increasing the size of the floor of the nostrils and the volume in the nasopharyngeal territory. Studies with a larger sample size and long-term follow-up are needed to establish the success of this therapy.


Assuntos
Técnica de Expansão Palatina , Maxila , Cavidade Nasal
5.
Front Cell Infect Microbiol ; 12: 949469, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36225231

RESUMO

Streptococcus pneumoniae is a Gram-positive bacterium and the leading cause of bacterial pneumonia in children and the elderly worldwide. Currently, two types of licensed vaccines are available to prevent the disease caused by this pathogen: the 23-valent pneumococcal polysaccharide-based vaccine and the 7-, 10, 13, 15 and 20-valent pneumococcal conjugate vaccine. However, these vaccines, composed of the principal capsular polysaccharide of leading serotypes of this bacterium, have some problems, such as high production costs and serotype-dependent effectiveness. These drawbacks have stimulated research initiatives into non-capsular-based vaccines in search of a universal vaccine against S. pneumoniae. In the last decades, several research groups have been developing various new vaccines against this bacterium based on recombinant proteins, live attenuated bacterium, inactivated whole-cell vaccines, and other newer platforms. Here, we review and discuss the status of non-capsular vaccines against S. pneumoniae and the future of these alternatives in a post-pandemic scenario.


Assuntos
Infecções Pneumocócicas , Idoso , Criança , Humanos , Imunização , Infecções Pneumocócicas/microbiologia , Vacinas Pneumocócicas , Proteínas Recombinantes , Sorogrupo , Streptococcus pneumoniae , Vacinas Conjugadas
6.
ACS Omega ; 7(24): 20457-20476, 2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35935292

RESUMO

The development of sustainable, cost-efficient, and high-performance nanofluids is one of the current research topics within drilling applications. The inclusion of tailorable nanoparticles offers the possibility of formulating water-based fluids with enhanced properties, providing unprecedented opportunities in the energy, oil, gas, water, or infrastructure industries. In this work, the most recent and relevant findings related with the development of customizable nanofluids are discussed, focusing on those based on the incorporation of 2D (two-dimensional) nanoparticles and environmentally friendly precursors. The advantages and drawbacks of using 2D layered nanomaterials including but not limited to silicon nano-glass flakes, graphene, MoS2, disk-shaped Laponite nanoparticles, layered magnesium aluminum silicate nanoparticles, and nanolayered organo-montmorillonite are presented. The current formulation approaches are listed, as well as their physicochemical characterization: rheology, viscoelastic properties, and filtration properties (fluid losses). The most influential factors affecting the drilling fluid performance, such as the pH, temperature, ionic strength interaction, and pressure, are also debated. Finally, an overview about the simulation at the microscale of fluids flux in porous media is presented, aiming to illustrate the approaches that could be taken to supplement the experimental efforts to research the performance of drilling muds. The information discussed shows that the addition of 2D nanolayered structures to drilling fluids promotes a substantial improvement in the rheological, viscoelastic, and filtration properties, additionally contributing to cuttings removal, and wellbore stability and strengthening. This also offers a unique opportunity to modulate and improve the thermal and lubrication properties of the fluids, which is highly appealing during drilling operations.

7.
An. Fac. Cienc. Méd. (Asunción) ; 55(2): 105-111, 20220801.
Artigo em Espanhol | LILACS | ID: biblio-1380455

RESUMO

Introducción: El presente artículo ahonda en las teorías más aceptadas sobre el proceso de erupción dental en la literatura de hoy en día y, desde este enfoque, expone el caso clínico de una paciente de 12 años de edad que presentaba retención de caninos y molares temporales. A dicha paciente se le trató clínicamente mediante exodoncias seriadas y se muestra su evolución posterior al tratamiento dental. Objetivos: Lograr entender de mejor manera el proceso de la erupción dental en base a la actual bibliografía. Materiales y métodos: Se realizó una revisión bibliográfica con palabras claves: "erupción dental", "extracciones seriadas", "retención dental" y "evolución dental". La paciente fue evaluada y tratada ortodóncicamente, mediante extracciones seriadas y se realizaron controles dentales periódicos con toma de radiografía panorámica para evaluar su evolución. Conclusión: El folículo dental y el retículo estrellado son las estructuras encargadas de generar el proceso eruptivo del diente mediante la interacción de diversas moléculas. Estas moléculas deben encajar dentro de un contexto para que cada diente erupcione de manera independiente.


Introduction: This article delves into the most accepted theories about the dental eruption process in today's literature and, from this perspective, presents the clinical case of a 12-year-old patient who presented retention of temporary canines and molars. This patient was treated clinically by means of serial extractions and her evolution after dental treatment is shown. Objectives: This article delves into the most accepted theories about the dental eruption process in today's literature and, from this perspective, presents the clinical case of a 12-year-old patient who presented retention of temporary canines and molars. This patient was treated clinically by means of serial extractions and her evolution after dental treatment is shown. Materials and methods: A bibliographic review was carried out with key words: "dental eruption", "serial extractions", "dental retention" and "dental evolution". The patient was evaluated and treated orthodontically by serial extractions and periodic dental check-ups were carried out with panoramic radiography to evaluate her evolution. Conclusion: The dental follicle and the stellate reticulum are the structures responsible for generating the eruptive process of the tooth through the interaction of various molecules. These molecules must fit into a context for each tooth to erupt independently.


Assuntos
Erupção Dentária , Dente
8.
PLoS Pathog ; 17(11): e1010042, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34748617

RESUMO

Rare and potent monoclonal antibodies (mAbs) against the Plasmodium falciparum (Pf) circumsporozoite protein (CSP) on infective sporozoites (SPZ) preferentially bind the PfCSP junctional tetrapeptide NPDP or NVDP minor repeats while cross-reacting with NANP central repeats in vitro. The extent to which each of these epitopes is required for protection in vivo is unknown. Here, we assessed whether junction-, minor repeat- and central repeat-preferring human mAbs (CIS43, L9 and 317 respectively) bound and protected against in vivo challenge with transgenic P. berghei (Pb) SPZ expressing either PfCSP with the junction and minor repeats knocked out (KO), or PbCSP with the junction and minor repeats knocked in (KI). In vivo protection studies showed that the junction and minor repeats are necessary and sufficient for CIS43 and L9 to neutralize KO and KI SPZ, respectively. In contrast, 317 required major repeats for in vivo protection. These data establish that human mAbs can prevent malaria infection by targeting three different protective epitopes (NPDP, NVDP, NANP) in the PfCSP repeat region. This report will inform vaccine development and the use of mAbs to passively prevent malaria.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Antiprotozoários/imunologia , Epitopos/imunologia , Malária Falciparum/prevenção & controle , Plasmodium falciparum/imunologia , Proteínas de Protozoários/imunologia , Esporozoítos/imunologia , Animais , Feminino , Fígado/imunologia , Fígado/metabolismo , Fígado/parasitologia , Fígado/patologia , Vacinas Antimaláricas/imunologia , Malária Falciparum/imunologia , Malária Falciparum/parasitologia , Camundongos , Camundongos Endogâmicos C57BL , Esporozoítos/crescimento & desenvolvimento
9.
Phys Chem Chem Phys ; 23(40): 22923-22935, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34617940

RESUMO

The performance of fibrous membrane composites fabricated via electrospinning is strongly influenced by the solution's properties, process variables and ambient conditions, although a precise mechanism for controlling the properties of the resulting composite has remained elusive. In this work, we focus on the fabrication of electrospun poly(vinylpyrrolidone) (PVP) fibers, by varying both the polymer concentration and the mixture of ethanol (EtOH) and dimethylformamide (DMF) used as solvent. The impact of the solvent composition on the structural properties is assessed by a combined experimental and theoretical approach, employing scanning electron microscopy (SEM), differential scanning calorimetry (DSC), rheology, Fourier-transform infrared spectroscopy (FTIR) and stress-strain curves obtained from tensile tests to characterize the fibrous membranes produced, and density functional theory (DFT) calculations to explain the solvent's affect on PVP crystallization. We establish a morphological phase diagram, and propose a possible mechanism based on the measured fiber diameter distribution, the viscoelastic properties of the precursor solution, the correlation between the functional groups and the mechanical properties, the thermal transitions and the degree of crystallinity. We also employ DFT calculations to model the polymer coverage at equilibrium of a PVP polymer chain in the presence of EtOH/DMF solvent mixtures to corroborate the crucial role their O or -OH groups play in achieving high PVP coverages and promoting the stability of the resulting fiber. These findings will be valuable to researchers interested in predicting, modulating, and controlling both a fiber's morphology and its concomitant physico-chemical properties.

10.
Emerg Infect Dis ; 27(5): 1438-1445, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33900173

RESUMO

Noroviruses are a leading cause of acute gastroenteritis (AGE) among adults and children worldwide. NoroSurv is a global network for norovirus strain surveillance among children <5 years of age with AGE. Participants in 16 countries across 6 continents used standardized protocols for dual typing (genotype and polymerase type) and uploaded 1,325 dual-typed sequences to the NoroSurv web portal during 2016-2020. More than 50% of submitted sequences were GII.4 Sydney[P16] or GII.4 Sydney[P31] strains. Other common strains included GII.2[P16], GII.3[P12], GII.6[P7], and GI.3[P3] viruses. In total, 22 genotypes and 36 dual types, including GII.3 and GII.20 viruses with rarely reported polymerase types, were detected, reflecting high strain diversity. Surveillance data captured in NoroSurv enables the monitoring of trends in norovirus strains associated childhood AGE throughout the world on a near real-time basis.


Assuntos
Infecções por Caliciviridae , Gastroenterite , Norovirus , Adulto , Criança , Genótipo , Humanos , Fígado , Filogenia
11.
Trials ; 22(1): 256, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33827659

RESUMO

BACKGROUND: Gestational diabetes mellitus (GDM) is associated with several maternal complications in pregnancy, including preeclampsia, preterm labor, need for induction of labor, and cesarean delivery as well as increased long-term risks of type 2 diabetes, metabolic syndrome, and cardiovascular disease. Intrauterine exposure to GDM raises the risk for complications in offspring as well, including stillbirth, macrosomia, and birth trauma, and long-term risk of metabolic disease. One of the strongest risk factors for GDM is the occurrence of GDM in a prior pregnancy. Preliminary data from epidemiologic and bariatric surgery studies suggest that reducing body weight before pregnancy can prevent the development of GDM, but no adequately powered trial has tested the effects of a maternal lifestyle intervention before pregnancy to reduce body weight and prevent GDM recurrence. METHODS: The principal aim of the Gestational Diabetes Prevention/Prevención de la Diabetes Gestacional is to determine whether a lifestyle intervention to reduce body weight before pregnancy can reduce GDM recurrence. This two-site trial targets recruitment of 252 women with overweight and obesity who have previous histories of GDM and who plan to have another pregnancy in the next 1-3 years. Women are randomized within site to a comprehensive pre-pregnancy lifestyle intervention to promote weight loss with ongoing treatment until conception or an educational control group. Participants are assessed preconceptionally (at study entry, after 4 months, and at brief quarterly visits until conception), during pregnancy (at 26 weeks' gestation), and at 6 weeks postpartum. The primary outcome is GDM recurrence, and secondary outcomes include fasting glucose, biomarkers of cardiometabolic disease, prenatal and perinatal complications, and changes over time in weight, diet, physical activity, and psychosocial measures. DISCUSSION: The Gestational Diabetes Prevention /Prevención de la Diabetes Gestacional is the first randomized controlled trial to evaluate the effects of a lifestyle intervention delivered before pregnancy to prevent GDM recurrence. If found effective, the proposed lifestyle intervention could lay the groundwork for shifting current treatment practices towards the interconception period and provide evidence-based preconception counseling to optimize reproductive outcomes and prevent GDM and associated health risks. TRIAL REGISTRATION: ClinicalTrials.gov NCT02763150 . Registered on May 5, 2016.


Assuntos
Diabetes Mellitus Tipo 2 , Diabetes Gestacional , Complicações na Gravidez , Cesárea , Diabetes Gestacional/diagnóstico , Diabetes Gestacional/prevenção & controle , Feminino , Humanos , Recém-Nascido , Estilo de Vida , Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto
12.
Int J Obes (Lond) ; 45(5): 1133-1142, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33627776

RESUMO

BACKGROUND/OBJECTIVES: We previously reported results from a randomized trial showing that a behavioral intervention during pregnancy reduced excess gestational weight gain but did not impact maternal weight at 12 months. We now examine the longer-term effects of this prenatal intervention on maternal postpartum weight retention and toddler body-mass-index z scores (BMIz) over 36 months. SUBJECTS/METHODS: Pregnant women (N = 264; 13.7 weeks' gestation; 41.6% Hispanic) with overweight or obesity were randomized into usual care or prenatal intervention. Anthropometric assessments in mothers and toddlers occurred at baseline, 35 weeks' gestation and after delivery at 6, 12, 18, 24, and 36 months. RESULTS: At 36 months, prenatal intervention vs. usual care had no significant effect on the proportion of participants who returned to their early pregnancy weight or below (33.3% vs. 39.5%; p = 0.12) and had no effect on the magnitude of weight retained (2.8 [0.8, 4.8] vs 3.0 kg [1.0, 4.9], respectively; mean difference = 0.14 [-3.0, 2.7]). There was also no statistically significant intervention vs. usual care effect on infant BMIz or skinfold changes over time; toddler BMIz increased by 1.4 [-1.7, 1.0] units in the intervention group and 1.6 [-1.2, 1.8] units in the usual care group from delivery to 36 months (difference = 0.16 [-0.32. 0.63]). The proportion of toddlers at risk for obesity at 36 months was similar in intervention and usual care groups (28/77 [36.4%] vs 30/80 [37.5%]; p = 0.77). CONCLUSIONS: Compared with usual care, lifestyle intervention during pregnancy resulted in similar maternal and toddler anthropometric outcomes at 36-months postpartum in a diverse US sample of women with overweight and obesity. To sustain improved maternal weight management initiated during pregnancy, continued intervention during the postpartum years may be needed.


Assuntos
Terapia Comportamental , Índice de Massa Corporal , Cuidado Pré-Natal , Redução de Peso , Adulto , Antropometria , Pré-Escolar , Feminino , Ganho de Peso na Gestação , Humanos , Estilo de Vida , Período Pós-Parto , Gravidez
13.
Polymers (Basel) ; 13(4)2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33578985

RESUMO

This work aims at bridging experimental and numerical approaches to determine the optimal operating parameters for the fabrication of well-shaped polyvinylpyrrolidone (PVP) particles via electrohydrodynamic atomization. Particular emphasis is given to the role of the PVP solution viscosity. Solutions of PVP at various concentrations dissolved in Dimethylformamide (DMF) were prepared and analyzed. Numerical simulation using a coupled electro-CFD model was used to determine the ranges of experimental flow rate and the voltage, ensuring that well-shaped spherical particles are produced. It was deduced that the optimal combination of the parameters (flow rate, voltage, and polymer concentration) can be well approximated by a scaling law. The established relationship allowed determination of a stability island that guarantees that the given polymer solution will form spherical particles. Analyzing morphology and sizes of the particles manufactured in the optimal parameters range, we show, among others, that the size of the PVP particles can be predicted as a function of the flow rate by a power scaling relationship.

14.
Opt Express ; 28(23): 34860-34874, 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33182945

RESUMO

In this paper, we present the simulation and experimental results of the first closed-loop system based on a directly modulated VCSEL in a gain-switching condition to generate optical frequency combs (OFC). In order to simulate the self-starting VCSEL-based optical frequency comb generator (SVOFC), we applied an intrinsic parameter extraction process to a C-band VCSEL using laser rate equations, static and dynamic measurements, and equivalent circuit models. The widest (62 GHz) and flattest (0.8) simulated OFC is obtained when the repetition frequency f0 is 2.5 GHz. Implementation of the C-band SVOFC also shows that under constant electrical conditions, flatness higher than 0.85 and spectral widths of 50 GHz are obtained when f0 = 2.5 GHz. The lowest phase noise at 10 kHz from the extracted electrical carrier is -127 dBc/Hz and is obtained when the optical fiber length is 5 km and f0 = 1.25 GHz.

15.
Obesity (Silver Spring) ; 28(10): 1860-1867, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32888250

RESUMO

OBJECTIVE: This cluster randomized trial tested whether an effective internet-based weight-loss intervention for low-income, postpartum women resulted in greater improvements in targeted social cognitive theory (SCT) constructs and psychosocial outcomes. METHODS: Fit Moms/Mamás Activas was a 12-month cluster randomized controlled trial of 370 postpartum women at 12 Special Supplemental Nutrition Program for Women, Infants, Children (WIC) clinics that were randomly assigned to intervention or standard WIC. SCT constructs (weight-control behaviors, cognitive restraint, disinhibition, self-efficacy, social support, body image) and psychosocial outcomes (depressive symptoms and stress) were measured at study entry and after 6 and 12 months. RESULTS: The intervention versus standard WIC resulted in greater 12-month increases in weight-control behaviors (3.28 points [95% CI: 1.06-5.50]), self-monitoring of weight and eating (2.28 points [1.17-3.40]), and cognitive restraint (1.93 points [0.78-3.08]) (all P ≤ 0.004). The intervention effect was only modestly (ηp 2 = 0.02) mediated by improvements in these factors. No significant group by time effect was observed for disinhibition, self-efficacy, social support, body image, depressive symptoms, or stress. CONCLUSIONS: Among low-income postpartum women, an effective internet-based weight-loss program resulted in improved weight-control behaviors and cognitive restraint but did not affect other SCT targets and psychosocial outcomes.


Assuntos
Intervenção Baseada em Internet/tendências , Período Pós-Parto/psicologia , Redução de Peso/fisiologia , Programas de Redução de Peso/métodos , Adolescente , Adulto , Feminino , Humanos , Adulto Jovem
16.
Front Plant Sci ; 11: 1171, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32849726

RESUMO

Communities of microorganisms in the soil can affect plants' growth and interactions with aboveground herbivores. Thus, there is growing interest in utilizing soil microbiomes to improve plant performance in agriculture (e.g., for pest control), but little is known about the phenotypic responses of various crop species to different microbiomes. In this study, we inoculated four crop species from different botanical families, maize (Zea mays, Poaceae), cucumber (Cucumis sativus, Cucurbitaceae), tomato (Solanum lycopersicum, Solanaceae), and lettuce (Lactuca sativa, Asteraceae), with diverse soil microbiomes originating from actively-managed agricultural fields or fallow fields under varying stages of succession (1, 3, and 16-years post-agriculture) sourced from a large-scale field experiment. We compared the crops' responses to these different microbiomes by assessing their growth and resistance to two generalist insect pests, cabbage looper (Trichoplusia ni) and fall armyworm (Spodoptera frugiperda). These different microbiomes affected both plant growth and resistance, but the effects were species-specific. For instance, lettuce produced the largest leaves when inoculated with a 3-year fallow microbiome, the microbiome in which cucumber performed worst. Plants were generally more resistant to T. ni when inoculated with the later succession microbiomes, particularly in contrast to those treated with agricultural microbiomes. However, for tomato plants, the opposite pattern was observed with regard to S. frugiperda resistance. Collectively, these results indicate that plant responses to microbiomes are species-specific and emphasize the need to characterize the responses of taxonomically diverse plant species to different microbiomes.

17.
Health Educ Behav ; 46(2_suppl): 114-123, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31742447

RESUMO

Internet-based weight loss programs can be effective in promoting weight loss and are less-intensive than traditional face-to-face approaches, which may provide more flexibility for postpartum, low-income women to engage in such programs. Few studies have examined patterns of engagement in internet-based programs for this population. This article used data from the internet-based Fit Moms/Mamás Activas intervention, a 12-month cluster randomized controlled trial that was effective in promoting postpartum weight loss among low-income, predominantly Hispanic women. The overall objectives of this study were to (1) characterize patterns of engagement with the Fit Moms/Mamás Activas website among intervention participants and (2) explore associations between engagement and 12-month weight loss outcomes among study completers (87.4%). A number of engagement variables were calculated for each participant, including website logins; time spent on the website; number of posts to the "Discussion Forum;" number of days tracking weight, diet, and physical activity; number of page visits to various website components; and number of in-person visits attended. The average number of logins was 70.74 (approximately once weekly), and average total time spent on the website was 185.35 minutes (approximately 3 hours) over 1 year. Self-monitoring ("Web Diary") and social support ("Discussion Forum") were the most frequently visited components of the website, and more frequent engagement with these components, as well as greater attendance at in-person group sessions, predicted greater percent weight loss at 12 months. Interventions highlighting these features may be particularly effective for weight loss in this population.


Assuntos
Internet , Período Pós-Parto , Pobreza , Telemedicina , Programas de Redução de Peso , Adulto , Análise por Conglomerados , Feminino , Humanos , Comportamento de Busca de Informação , Período Pós-Parto/etnologia , Estados Unidos
18.
BMC Oral Health ; 19(1): 207, 2019 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-31484557

RESUMO

BACKGROUND: The oral flagellated protozoan Trichomonas tenax has been associated with patients with periodontal disease. However, no recent studies have been conducted on the prevalence of T. tenax in Chile. The aim of this study was to determine the presence of T. tenax in patients with periodontal disease, admitted to the Dental Clinic of the University of Antofagasta, Chile, through Polymerase Chain Reaction (PCR) amplification of the beta-tubulin gene. METHODS: An observational, cross-sectional study was conducted on 50 patients diagnosed with periodontal disease, 20 of them with gingivitis and 30 with periodontitis. T. tenax was identified by PCR amplification of the beta-tubulin gene. Associations between the protozoan and periodontal disease or the presence of risk factors to establish T. tenax infection were determined using the chi-square test and binary logistic regression analysis. RESULTS: T. tenax was present in 28 out of 50 (56%) of patients with periodontal disease, and was more prevalent when associated with periodontitis (21 out of 30; 70%) than dental plaque-induced gingivitis (7 out of 20; 35%). Non-statistically-significant associations were observed between the presence of T. tenax and age, gender, smoking habit or diabetes. Statistically significant associations were observed between the presence of T. tenax and periodontal disease, and between T. tenax and the Periodontal Screening and Recording (PSR) index. CONCLUSION: T. tenax showed a high presence in patients with progressive states of periodontal diseases. Consequently, T. tenax detection is strongly recommended in patients with periodontal disease diagnosis and with a PSR index greater than 3.


Assuntos
Gengivite/microbiologia , Doenças Periodontais/microbiologia , Tricomoníase/diagnóstico , Trichomonas/isolamento & purificação , Tubulina (Proteína)/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Chile/epidemiologia , Estudos Transversais , Clínicas Odontológicas , Feminino , Amplificação de Genes , Gengivite/diagnóstico , Gengivite/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Periodontais/diagnóstico , Doenças Periodontais/epidemiologia , Reação em Cadeia da Polimerase , Prevalência , Universidades
19.
Obesity (Silver Spring) ; 27(2): 226-236, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30421864

RESUMO

OBJECTIVE: This randomized trial tested whether a behavioral intervention with meal replacements in pregnancy could increase the proportion of women who returned to prepregnancy weight and reduce postpartum weight retention by 12 months after delivery. METHODS: Women (N = 264; 13.7 weeks' gestation) with overweight or obesity were randomly assigned to usual care or intervention. The intervention reduced excess gestational weight gain and was discontinued at delivery. At follow-up, 83.7% completed the 12-month assessment. RESULTS: Compared with usual care, prenatal intervention had no significant effect on odds of achieving prepregnancy weight (38/128 [29.7%] vs. 41/129 [31.8%]; P = 0.98) or in reducing the magnitude of weight retained (3.3 vs. 3.1 kg; P = 0.82) at 12 months. After delivery, significant (P < 0.0001) declines in meal replacements, practice of weight control behaviors, and dietary restraint were observed in the intervention group. Independent of group, lower gestational weight gain was the strongest predictor of achieving prepregnancy weight at 12 months (P = 0.0008). CONCLUSIONS: A prenatal behavioral intervention with meal replacements that reduced pregnancy weight gain had no significant effect on 12-month postpartum weight retention.


Assuntos
Ganho de Peso na Gestação/fisiologia , Refeições/fisiologia , Obesidade/dietoterapia , Período Pós-Parto/psicologia , Complicações na Gravidez/dietoterapia , Adulto , Dieta , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Estilo de Vida , Gravidez , Fatores de Tempo , Adulto Jovem
20.
Pediatr Obes ; 14(1)2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30225981

RESUMO

BACKGROUND: Weight loss interventions can have positive 'ripple' effects on untreated partners in the home, but ripple effects on infants are unknown. OBJECTIVE: To examine whether a 12-month internet-based weight loss intervention for postpartum mothers had a positive ripple effect on participants' infants. METHODS: A 12-month cluster randomized, assessor-blind, clinical trial enrolling 371 postpartum women at 12 Women, Infants, Children clinics in CA. Clinics were randomized to standard Women, Infants, Children or an internet-based weight loss intervention for mothers. RESULTS: A total of 333 of the 371 (89.8%) mothers assented for infant participation. Infants were 5.3 ± 3.2 months; 75.9% were Hispanic and 64% were breastfeeding. Infant retention was 272/333 (82.7%) at 6 months post enrollment and 251/333 (75.3%) at 12 months post enrollment. In intent-to-treat analysis, a significant interaction between group and time was observed (p = 0.008) with the offspring of intervention mothers exhibiting lower zBMI change from study entry through 6 months (0.23 [CI, 0.03, 0.44] vs. 0.65 [0.50, 0.79] zBMI change, respectively; p = 0.001) but was not significant through 12 months (p = 0.16). Regardless of group, maternal reports at the final assessment indicated that infants (aged =17.2 ± 3.4 months) consumed sweetened beverages (0.93 ± 1.5/week), juice (2.0 ± 1.4/day), 'junk food' (7.8 ± 5.4/week) and fast food (2/month), and 46.7% of the infants had a TV in their bedroom. CONCLUSIONS: An internet-based weight loss program for low-income, postpartum mothers had a positive 'ripple' effect on the zBMI of infants in the home during the first 6 months of treatment.


Assuntos
Índice de Massa Corporal , Desenvolvimento Infantil/fisiologia , Telemedicina/métodos , Programas de Redução de Peso/métodos , Adolescente , Adulto , Criança , Feminino , Humanos , Lactente , Comportamento do Lactente/psicologia , Internet , Masculino , Mães , Período Pós-Parto/fisiologia , Pobreza , Adulto Jovem
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