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1.
Langmuir ; 37(15): 4666-4677, 2021 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-33826345

RESUMEN

In pursuit of friendlier conditions for the preparation of high-value biochemicals, we developed catalytic synthesis of γ-valerolactone by levulinic acid hydrogenation with formic acid as the hydrogen source. Both levulinic and formic acid are intermediate products in the biomass transformation processes. The objective of the work is twofold: the development of a novel approach for milder synthesis conditions to produce γ-valerolactone and the reduction of the economic cost of the catalyst. Ni-rich Ni-Pt mesoporous nanowires were synthesized in an aqueous medium using a combined hard-soft-template-assisted electrodeposition method, in which porous polycarbonate membranes controlled the shape and the Pluronic P-123 copolymer served as the porogen agent. The electrodeposition conditions selected favored nickel deposition and generated nanowires with nickel percentages above 75 atom %. The increase in deposition potential favored nickel deposition. However, it was detrimental for the porous diameter because the mesoporous structure is promoted by the presence of the platinum-rich micelles near the substrate, which is not favored at more negative potentials. The prepared catalysts promoted the complete transformation to γ-valerolactone in a yield of around 99% and proceeded with the absence of byproducts. The coupling temperature and reaction time were optimized considering the energy cost. The threshold operational temperature was established at 140 °C, at which, 120 min was sufficient for attaining the complete transformation. Working temperatures below 140 °C rendered the reaction completion difficult. The Ni78Pt22 nanowires exhibited excellent reusability, with minimal nickel leaching into the reaction mixture, whereas those with higher nickel contents showed corrosion.

2.
Clin Obstet Gynecol ; 59(3): 639-44, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27398880

RESUMEN

In recent years it has been recognized that in all phases of life, including pregnancy, physical activity promotes health benefits and precludes comorbidities, the scientific evidence is indisputable. Several organizations around the world have updated in recent years the guidelines and recommendations for exercise in pregnancy. The December 2015, updated guidelines of the American College of Obstetricians and Gynecologists emphasize that physical activity in pregnancy has minimal risk. Although recommending exercise in pregnancy, the anatomic/physiological changes, absolute and relative contraindications should be considered. Women who exercised regularly before pregnancy, in the absence of contraindications, can continue and engage in moderate to strenuous activities, although information on strenuous activities in pregnancy is still limited. This review summarizes the most recent published and recommended guidelines.


Asunto(s)
Ejercicio Físico , Guías de Práctica Clínica como Asunto , Embarazo , Femenino , Estilo de Vida Saludable , Humanos , Obesidad/prevención & control , Periodo Posparto , Complicaciones del Embarazo/prevención & control , Riesgo
3.
Clin Obstet Gynecol ; 59(3): 620-8, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27135873

RESUMEN

Exercise plays an important role in reducing the prevalence of gestational diabetes mellitus (GDM) in women with or without risk factors. GDM risk factors include obesity, family history of diabetes, high-risk ethnicity, increased maternal age, history of GDM, delivering a macrosomic infant, excessive gestational weight gain early in pregnancy (before glucose screening), sedentary behavior, low physical activity, and vitamin D deficiency. Most GDM patients can be managed with lifestyle modifications that include medical nutrition therapy and physical activity. When adherence is high and women are fully engaged in the exercise program, GDM can be effectively managed and prevented.


Asunto(s)
Diabetes Gestacional/terapia , Ejercicio Físico/fisiología , Diabetes Gestacional/prevención & control , Femenino , Humanos , Guías de Práctica Clínica como Asunto , Embarazo , Factores de Riesgo
4.
Br J Sports Med ; 50(21): 1297-1305, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27733352

RESUMEN

This is Part 2 of 5 in the series of evidence statements from the IOC expert committee on exercise and pregnancy in recreational and elite athletes. Part 1 focused on the effects of training during pregnancy and on the management of common pregnancy-related symptoms experienced by athletes. In Part 2, we focus on maternal and fetal perinatal outcomes.

5.
Twin Res Hum Genet ; 17(2): 127-33, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24423582

RESUMEN

Limited data is available that estimates the effect of gestational weight gain on maternal and neonatal outcomes in term twin pregnancies in obese women. A historical cohort study of 831 obese (BMI ≥30.0 kg/m2) women in Missouri delivering 1,662 liveborn, term (≥37 weeks gestation) twin infants in 1998-2005 was conducted. Three gestational weight gain categories were examined: <25 pounds, 25-42 pounds, and >42 pounds. Adjusted odds ratios were calculated with multiple logistic regression, using the 2009 Institute of Medicine provisional guideline of 25-42 pounds as the reference group. Significant increasing trends with gestational weight gain were found for preeclampsia (p < .05), larger twin birth weight (p < .01), smaller twin birth weight (p < .001), and infants weighing >2,500 grams (p < .001). Significant increasing trends for preeclampsia and for cesarean delivery were found in concordant twin pairs (smaller twin >80% of birth weight of larger twin). Women who gained >42 pounds had a borderline significantly higher odds of preeclampsia than women who gained 25-42 pounds (adjusted OR 1.72; 95% CI 1.00-2.99, p = .052). No significant differences were found for 1-min Apgar score <4, 5-min Apgar score <7, or infant mortality ≤1 year. Our study suggests that increasing gestational weight gain is associated with larger infants but increased risk of preeclampsia and cesarean delivery in term twin pregnancies in obese women. Limiting gestational weight gain could reduce the risk of preeclampsia and cesarean delivery. Prospective studies of other study populations and maternal/infant outcomes are needed to evaluate the efficacy of the Institute of Medicine guideline.


Asunto(s)
Obesidad/epidemiología , Complicaciones del Embarazo/epidemiología , Resultado del Embarazo/epidemiología , Embarazo Gemelar/estadística & datos numéricos , Aumento de Peso , Adulto , Femenino , Humanos , Embarazo , Factores de Riesgo
6.
Matern Child Health J ; 18(4): 1038-47, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24077985

RESUMEN

Small-for-gestational-age (SGA) and large-for gestational-age (LGA) infants are associated with increased adverse outcomes. While studies have estimated the association of gestational weight gain with birth weight in obese women, estimates are lacking by obesity class and diabetic status. A population-based historical cohort study of 66,010 obese pregnant women in Missouri delivering liveborn, singleton, term infants in 2002­2008 was conducted. Adjusted odds ratios for SGA and LGA infants were calculated for gestational weight gain categories with multiple logistic regression using the revised Institute of Medicine(IOM) recommended 11­20 pounds as the reference group. A weight gain of 3­10 pounds was not significantly associated with an increased risk of an SGA infant compared to 11­20 pounds in 5/6 obesity class/diabetic status combinations.The exception was Class I Obese non-diabetic women(adjusted odds ratio = 1.28, 95 % confidence interval 1.07, 1.52). When lower amounts of weight gain were considered, diabetic women who gained ≤2 pounds (including women who lost weight) did not have a significantly increased risk of an SGA infant compared to diabetic women who gained 11­20 pounds in any obesity class. Weight gains less than 11­20 pounds were significantly associated with a decreased risk of an LGA infant in 5/6 obesity class/diabetic status combinations. Weight gains lower than the IOM recommendation of 11­20 pounds during pregnancy for obese women generally were significantly associated with decreased risk of LGA infants without being significantly associated with increased risk of SGA infants and differed by obesity class and diabetic status.


Asunto(s)
Peso al Nacer , Diabetes Mellitus/fisiopatología , Obesidad/complicaciones , Complicaciones del Embarazo/fisiopatología , Resultado del Embarazo , Aumento de Peso/fisiología , Adulto , Índice de Masa Corporal , Estudios de Cohortes , Intervalos de Confianza , Femenino , Macrosomía Fetal/epidemiología , Macrosomía Fetal/fisiopatología , Edad Gestacional , Humanos , Recién Nacido , Recién Nacido Pequeño para la Edad Gestacional , Masculino , Análisis Multivariante , Obesidad/diagnóstico , Oportunidad Relativa , Embarazo , Adulto Joven
8.
Nat Commun ; 15(1): 7501, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39209828

RESUMEN

Halide solid electrolytes do not currently display ionic conductivities suitable for high-power all-solid-state batteries. We explore the model system A2ZrCl6 (A = Li, Na, Cu, Ag) to understand the fundamental role that A-site chemistry plays on fast ion transport. Having synthesised the previously unknown Ag2ZrCl6 we reveal high room temperature ionic conductivities in Cu2ZrCl6 and Ag2ZrCl6 of 1 × 10-2 and 4 × 10-3 S cm-1, respectively. We introduce the concept that there are inherent limits to ionic conductivity in solids, where the energy and number of transition states play pivotal roles. Transport that involves multiple coordination changes along the pathway suffer from an intrinsic minimum activation energy. At certain lattice sizes, the energies of different coordinations can become equivalent, leading to lower barriers when a pathway involves a single coordination change. Our models provide a deeper understanding into the optimisation and design criteria for halide superionic conductors.

9.
Am J Obstet Gynecol ; 208(3): 205.e1-7, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23246318

RESUMEN

OBJECTIVE: The purpose of this study was to estimate the impact of interpregnancy weight change from first to second pregnancies in obese women on the risk of large-for-gestational-age (LGA) and small-for-gestational-age (SGA) infants. STUDY DESIGN: A population-based historical cohort analysis of 10,444 obese women in Missouri who delivered their first 2 singleton live infants from 1998-2005. Interpregnancy weight change was calculated as the difference between prepregnancy body mass index (BMI) of the first and second pregnancies. LGA and SGA births were compared among 3 interpregnancy weight change groups: (1) weight loss (≥2 BMI units), (2) weight gain (≥2 BMI units), and (3) reference group (BMI maintained within 2 units). Adjusted odds ratios (aOR) were calculated for LGA and SGA births with the use of multiple logistic regression. A dose-response relationship was assessed with a linear-by-linear χ(2) test. RESULTS: Compared with the reference group, interpregnancy weight loss was associated with lower risk of an LGA infant (aOR, 0.61; 95% confidence interval, 0.52-0.73), whereas interpregnancy weight gain was associated with increased risk of an LGA infant (aOR, 1.37; 95% confidence interval, 1.21-1.54). Interpregnancy BMI change was not related to SGA infant risk, except for weight loss of >8 BMI units. A significant dose-response relationship was observed for LGA infant risk (P < .001), but not SGA infant risk (P = .840). CONCLUSION: Mild-to-moderate interpregnancy weight loss in obese women reduced the risk of subsequent birth of LGA infants without increasing the risk of SGA infants. The interpregnancy interval may be a crucial period for targeting weight loss in obese women.


Asunto(s)
Peso al Nacer/fisiología , Peso Corporal/fisiología , Obesidad/fisiopatología , Aumento de Peso/fisiología , Pérdida de Peso/fisiología , Adulto , Índice de Masa Corporal , Femenino , Humanos , Recién Nacido , Embarazo , Factores de Riesgo
14.
J Infect Dis ; 204(6): 854-63, 2011 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-21849282

RESUMEN

BACKGROUND: Although pregnant women are at increased risk of severe illness following influenza infection, there is relatively little information on the immunogenicity of influenza vaccines administered during pregnancy. METHODS: We conducted a clinical trial that enrolled 120 pregnant women in which participants were randomly assigned to receive an inactivated 2009 H1N1 influenza vaccine containing either 25 µg or 49 µg of hemagglutinin (HA) in a 2-dose series with a 21-day period between administration of the first and second doses. RESULTS: Following the first vaccination, HA inhibition (HAI) titers of ≥1:40 were detected in 93% (95% confidence interval [CI], 82%-98%) of subjects who received the 25-µg dose and 97% (95% CI, 88%-100%) of subjects receiving the 49-µg dose. In cord blood samples, HAI titers of ≥1:40 were found in 87% (95% CI, 73%-96%) of samples from the 25-µg dose group and in 89% (95% CI, 76%-96%) from the 49-µg dose group. Microneutralization titers tended to be higher than HAI titers, but the patterns of response were similar. CONCLUSIONS: In pregnant women, 1 dose of an inactivated 2009 H1N1 influenza vaccine containing 25 µg of HA elicited an antibody response typically associated with protection against influenza infection. Efficient transplacental transfer of antibody was also documented.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A/inmunología , Vacunas contra la Influenza/inmunología , Gripe Humana/prevención & control , Adolescente , Adulto , Anticuerpos Antivirales/sangre , Femenino , Humanos , Inmunización Secundaria/métodos , Vacunas contra la Influenza/administración & dosificación , Embarazo , Vacunación/métodos , Vacunas de Productos Inactivados/administración & dosificación , Vacunas de Productos Inactivados/inmunología , Adulto Joven
15.
Appl Physiol Nutr Metab ; 47(7): 787-803, 2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35442812

RESUMEN

Evidence-based guidelines represent the highest level of scientific evidence to identify best practices for clinical/public health. However, the availability of guidelines do not guarantee their use, targeted knowledge translation strategies and tools are necessary to help promote uptake. Following publication of the 2019 Canadian Guideline for Physical Activity throughout Pregnancy, the Get Active Questionnaire for Pregnancy, and an associated Health Care Provider Consultation Form for Prenatal Physical Activity were developed to promote guideline adoption and use amongst pregnant individuals and health care providers. This paper describes the process of developing these tools. First, a survey was administered to qualified exercise professionals to identify the barriers and facilitators in using existing prenatal exercise screening tools. A Working Group of researchers and stakeholders then convened to develop an evidence-informed exercise pre-participation screening tool for pregnant individuals, building from previous tool and survey findings. Finally, end-user feedback was solicited through a survey and key informant interviews to ensure tools are feasible and acceptable to use in practice. The uptake and use of these documents by pregnant individuals, exercise, and health care professionals will be assessed in future studies. Novelty: Evidence supports the safety/benefits of exercise for most pregnant individuals; however, exercise is not recommended for a small number of individuals with specific medical conditions. The Get Active Questionnaire for Pregnancy and Health Care Provider Consultation Form for Physical Activity during Pregnancy identify individuals where prenatal exercise may pose a risk, while reducing barriers to physical activity participation for the majority of pregnant individuals.


Asunto(s)
Terapia por Ejercicio , Ejercicio Físico , Canadá , Femenino , Humanos , Embarazo , Encuestas y Cuestionarios
17.
Br J Sports Med ; 50(10): 571-89, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27127296
18.
Nanomaterials (Basel) ; 10(8)2020 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-32717944

RESUMEN

The use of soft templates for the electrosynthesis of mesoporous materials has shown tremendous potential in energy and environmental domains. Among all the approaches that have been featured in the literature, block copolymer-templated electrodeposition had robustness and a simple method, but it practically cannot be used for the synthesis of mesoporous materials not based on Pt or Au. Nonetheless, extending and understanding the possibilities and limitations of block copolymer-templated electrodeposition to other materials and substrates is still challenging. Herein, a critical analysis of the role of the solution's primary electroactive components and the applied potential were performed in order to understand their influences on the mesostructure of Ni-rich Ni-Pt mesoporous films. Among all the components, tetrahydrofuran and a platinum (IV) complex were shown to be crucial for the formation of a truly 3D mesoporous network. The electrosynthesized well-ordered mesoporous Ni-rich Ni-Pt deposits exhibit excellent electrocatalytic performance for methanol oxidation in alkaline conditions, improved stability and durability after 1000 cycles, and minimal CO poisoning.

19.
Adv Sci (Weinh) ; 7(3): 1902447, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32042564

RESUMEN

Water remediation and development of carbon-neutral fuels are a priority for the evermore industrialized society. The answer to these challenges should be simple, sustainable, and inexpensive. Thus, biomimetic-inspired circular and holistic processes combing water remediation and biofuel production can be an appealing concept to deal with these global issues. A simple circular approach using helical Spirulina platensis microalgae as biotemplates to synthesize Ni@ZnO@ZnS photocatalysts for efficient solar water decontamination and bioethanol production during the recycling process is presented. Under solar irradiation, the Ni@ZnO@ZnS-Spirulina photocatalyst exhibits enhanced activity (mineralization efficiency >99%) with minimal photocorrosion and excellent reusability. At the end of its effective lifetime for water remediation, the microalgae skeleton (mainly glycogen and glucose) of the photocatalyst is recycled to directly produce bioethanol by simultaneous saccharification and fermentation process. An outstanding ethanol yield of 0.4 L kg-1, which is similar to the highest yield obtained from oxygenic photosynthetic microorganisms, is obtained. Thus, the entire process allows effective solar photocatalytic water remediation and bioethanol production at room temperature using simple and easily scalable procedures that simultaneously fixes carbon dioxide, thereby constituting a zero-carbon-emission circular process.

20.
Obstet Gynecol Surv ; 74(8): 481-489, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31418450

RESUMEN

IMPORTANCE: Physical activity during pregnancy can offer many maternal and fetal health benefits. OBJECTIVE: The aim was to summarize American, Canadian, and international recommendations published recently on physical activity during pregnancy to aid health care providers in their delivery of advice on the topic. EVIDENCE ACQUISITION: A descriptive review of 3 national guidelines and 1 international guideline on physical activity during pregnancy was conducted. The guidelines included the 2019 Canadian recommendations, the 2018 United States' Physical Activity Guidelines for Americans (second edition), the 2015 (reaffirmed in 2017) American College of Obstetrics and Gynecology guideline, and the 2016-2018 International Olympic Committee recommendations for recreational and elite athletes. RESULTS: For apparently healthy women, under the guidance of their health care provider, moderate-intensity physical activity using both aerobic and muscle conditioning activities is recommended. The guidelines recommended at least 150 min/wk spread throughout the week (Canada, United States) or at least 20 to 30 min/d (American College of Obstetrics and Gynecology). CONCLUSIONS AND RELEVANCE: This summary of 4 recent guidelines can facilitate use of updated recommendations by health care providers regarding physical activity during pregnancy. More detailed evidence-based guidelines on physical activity during postpartum are needed.


Asunto(s)
Terapia por Ejercicio/normas , Ejercicio Físico , Obstetricia/normas , Guías de Práctica Clínica como Asunto , Atención Prenatal/normas , Canadá , Femenino , Humanos , Embarazo , Estados Unidos
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