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1.
Small ; : e2401474, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39248703

RESUMEN

In this short review, an overview of recent progress in deploying advanced characterization techniques is provided to understand the effects of spatial variation and inhomogeneities in moiré heterostructures over multiple length scales. Particular emphasis is placed on correlating the impact of twist angle misalignment, nano-scale disorder, and atomic relaxation on the moiré potential and its collective excitations, particularly moiré excitons. Finally, future technological applications leveraging moiré excitons are discussed.

2.
Proc Natl Acad Sci U S A ; 113(14): 3832-7, 2016 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-27001849

RESUMEN

Plant respiration constitutes a massive carbon flux to the atmosphere, and a major control on the evolution of the global carbon cycle. It therefore has the potential to modulate levels of climate change due to the human burning of fossil fuels. Neither current physiological nor terrestrial biosphere models adequately describe its short-term temperature response, and even minor differences in the shape of the response curve can significantly impact estimates of ecosystem carbon release and/or storage. Given this, it is critical to establish whether there are predictable patterns in the shape of the respiration-temperature response curve, and thus in the intrinsic temperature sensitivity of respiration across the globe. Analyzing measurements in a comprehensive database for 231 species spanning 7 biomes, we demonstrate that temperature-dependent increases in leaf respiration do not follow a commonly used exponential function. Instead, we find a decelerating function as leaves warm, reflecting a declining sensitivity to higher temperatures that is remarkably uniform across all biomes and plant functional types. Such convergence in the temperature sensitivity of leaf respiration suggests that there are universally applicable controls on the temperature response of plant energy metabolism, such that a single new function can predict the temperature dependence of leaf respiration for global vegetation. This simple function enables straightforward description of plant respiration in the land-surface components of coupled earth system models. Our cross-biome analyses shows significant implications for such fluxes in cold climates, generally projecting lower values compared with previous estimates.


Asunto(s)
Aclimatación/fisiología , Respiración de la Célula/fisiología , Metabolismo Energético/fisiología , Hojas de la Planta/metabolismo , Árboles/metabolismo , Ciclo del Carbono , Dióxido de Carbono/metabolismo , Cambio Climático , Ecosistema , Calor
3.
Am J Hum Biol ; 28(2): 233-5, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26179833

RESUMEN

OBJECTIVE: to assess the utility of body mass index (BMI) and waist circumference (WC) as surrogate indicators of adiposity with respect to the total body fat estimated with bioimpedance analysis in psychogeriatric patients. METHODS: Anthropometric and hand-to-foot bioimpedance measurements were performed according to standard procedures in a sample of 128 psychogeriatric patients (87 males, 41 females). WC cutoffs proposed by the International Diabetes Federation were used to define abdominal obesity. Z-scores of fat and fat-free mass indices (Z-FMI and Z-FFMI) were calculated. RESULTS: Males with WC values below the cutoff were normal weight, and showed normal levels of FM and low FFM (Z-FFMI below 1.5 SD). Males with WC values above the cutoff were overweight, showed high levels of FM (Z-FMI: 1.34 SD) and a slight depletion of FFM (Z-FFMI: -0.59 SD). In females with WC values below the cutoff, BMI was close to 20 kg/m(2) and both FM and FFM were depleted (Z-FMI: -0.7 SD; Z-FFMI: -1.76 SD). In females with WC above the cutoff, the average BMI was 25.6 kg/m(2) , Z-FMI was 0.48 SD, and Z-FFMI was -0.56 SD. CONCLUSIONS: Our results indicate that it is necessary to establish age and sex-specific BMI and WC cutoffs, and also highlight the importance of focusing on body composition analysis to ensure an accurate nutritional diagnosis in older-adults and in psychogeriatric patients.


Asunto(s)
Tejido Adiposo/anatomía & histología , Adiposidad , Antropometría , Índice de Masa Corporal , Circunferencia de la Cintura , Factores de Edad , Anciano , Anciano de 80 o más Años , Impedancia Eléctrica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Obesidad/diagnóstico , Sobrepeso/diagnóstico , Factores Sexuales , España
5.
ACS Appl Electron Mater ; 6(9): 6820-6825, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39345271

RESUMEN

In this study, we report a tetragonal perovskite structure of SrIrO3 (P4/mmm, a = 3.9362(9) Å, c = 7.880(3) Å) synthesized at 6 GPa and 1400 °C, employing the ambient pressure monoclinic SrIrO3 with distorted 6H structure as a precursor. The crystal structure of tetragonal SrIrO3 was evaluated on the basis of single-crystal and powder X-ray diffraction. A cubic indexing was observed, which was attributed to overlooked superlattice reflections. Weak fractional peaks in the H and K dimensions suggest possible structure modulation by oxygen defects. Magnetization study reveals weak paramagnetic behavior down to 2 K, indicative of the interplay between spin-orbit coupling, electron correlations, and the crystal electric field. Additionally, measurements of electrical resistivity display metallic behavior with an upturn at about 54 K, which is ascribed to weak electron localization and possible structural defects.

6.
Nanophotonics ; 12(7): 1199-1244, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36969949

RESUMEN

Frequency conversion in nonlinear materials is an extremely useful solution to the generation of new optical frequencies. Often, it is the only viable solution to realize light sources highly relevant for applications in science and industry. In particular, supercontinuum generation in waveguides, defined as the extreme spectral broadening of an input pulsed laser light, is a powerful technique to bridge distant spectral regions based on single-pass geometry, without requiring additional seed lasers or temporal synchronization. Owing to the influence of dispersion on the nonlinear broadening physics, supercontinuum generation had its breakthrough with the advent of photonic crystal fibers, which permitted an advanced control of light confinement, thereby greatly improving our understanding of the underlying phenomena responsible for supercontinuum generation. More recently, maturing in fabrication of photonic integrated waveguides has resulted in access to supercontinuum generation platforms benefiting from precise lithographic control of dispersion, high yield, compact footprint, and improved power consumption. This Review aims to present a comprehensive overview of supercontinuum generation in chip-based platforms, from underlying physics mechanisms up to the most recent and significant demonstrations. The diversity of integrated material platforms, as well as specific features of waveguides, is opening new opportunities, as will be discussed here.

7.
Curr Opin Clin Nutr Metab Care ; 12(3): 251-7, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19363338

RESUMEN

PURPOSE OF REVIEW: To provide recent observations on the interrelation between chronic heart failure (CHF), cachexia and human nutrition and updating epidemiological issues in CHF. RECENT FINDINGS: Present evidence suggests that impairment in cardiac muscle energetics plays an important role in the pathogenesis of heart failure. New concepts such as microRNA expression are emerging as potential agents in heart failure. Recent research suggests mechanisms by which inflammatory catabolic states may persist in the presence of adequate growth factors and nutrition. A consensus panel has recently designed a definition for general cachexia and its stratification. Together with classicals, new nutrients and substrates are showing efficacies in the malnutrition associated with CHF. Although still promising, ghrelin, growth factors and other biological compounds maintain emergent therapeutical positions for heart failure or associated catabolic states or both. SUMMARY: Altered intestinal function as an agent for CHF is rising in evidence. New techniques to well diagnose and stratify malnutrition and cardiac cachexia in CHF are needed. Treatment of cachexia in CHF appears to be a combination of different approaches, in which metabolic, nutritional, immunological and hormonal strategies may play an important role. Although the current experimental research is of great help, well designed randomized controlled trials are needed to test these hypothesis and generate clinical evidence.


Asunto(s)
Caquexia , Insuficiencia Cardíaca , Terapia Nutricional , Caquexia/diagnóstico , Caquexia/etiología , Caquexia/terapia , Enfermedad Crónica , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/etiología , Insuficiencia Cardíaca/terapia , Humanos
8.
Nutrition ; 63-64: 87-91, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30933731

RESUMEN

OBJECTIVES: Anorexia nervosa (AN) is a complex disease that involves malnutrition and a profound depletion in muscle mass. The thickness of the adductor pollicis muscle (APM) has been proposed as a new anthropometric technique to estimate muscle mass, check early changes, and assess its evaluation. This study aimed to evaluate the accuracy and validity of the APM thickness in a cohort of malnourished patients with AN when checking local mass gain. The Doppler ultrasound maybe an affordable and useful method to discriminate all tissues around the APM area. METHODS: A prospective cohort study was conducted of 31 malnourished patients with AN who were admitted to the Regional Eating Disorders Unit for treatment, including re-alimentation. Anthropometric measurements were taken, including arm circumference, triceps skinfold thickness, arm muscle circumference, body mass index, and APM thickness of both hands. Simultaneously, a Doppler ultrasound was performed in the same area, measuring and discriminating fat, skin, and muscle tissues around the APM. RESULTS: Nutritional improvement is accompanied by fat, but not muscle gain in the hand in the adductor pollicis area of patients with AN. A Doppler ultrasound can accurately discriminate between tissues around the APM. CONCLUSIONS: APM thickness reflects the addition of two different muscles plus fat and skin; therefore, this tool is not reliable to assess APM mass.


Asunto(s)
Anorexia Nerviosa/fisiopatología , Desnutrición/fisiopatología , Atrofia Muscular/diagnóstico , Grosor de los Pliegues Cutáneos , Adulto , Anorexia Nerviosa/complicaciones , Antropometría , Índice de Masa Corporal , Femenino , Humanos , Masculino , Desnutrición/etiología , Músculo Esquelético/fisiopatología , Atrofia Muscular/etiología , Evaluación Nutricional , Estudios Prospectivos , Reproducibilidad de los Resultados , Adulto Joven
9.
Artículo en Inglés, Español | MEDLINE | ID: mdl-27156787

RESUMEN

INTRODUCTION: Clozapine is an antipsychotic drug that has shown to be more effective than other antipsychotics in the treatment of schizophrenia, but its use is limited due to its side effects, particularly by the risk of causing agranulocytosis. A study was made on the variations in white cell and neutrophil counts in patients treated with clozapine in a Long-term Psychiatric Unit. METHODS: A retrospective observational study was conducted with a sample of women of our long-term psychiatric care unit who had been treated with clozapine. A study was made on the variations in white cell and neutrophil counts during the first 18 weeks of treatment, as well as the onset of leukopenia, neutropenia, agranulocytosis, and the influence of concomitant drugs. RESULTS AND CONCLUSIONS: The study included 55 patients on treatment with clozapine. The incidence rate of neutropenia was 1.82% (95% CI; 0.05-10.13). The incidence rate of leukopenia and agranulocytosis was 0%. An increase in white cell and neutrophil counts from baseline to week 3-4 was observed. Only small variations were observed after this time, but the counts remained higher than the initial values. These changes were statistically significant in the white cell count: One-way repeated ANOVA with Greenhouse-Geisser correction F (11.47, 37) = 2.114 (P= .011); and in neutrophils: One-way repeated ANOVA with Greenhouse-Geisser correction F (10.3, 37)=3.312 (P=.0002), and MANOVA F (18, 37)=2.693 (P=.005), ŋ2P=0.567. The influence of concomitant drugs (lithium, valproic and biperiden) was not significant on the overall increase found in white cells or neutrophils (MANOVA).


Asunto(s)
Antipsicóticos/efectos adversos , Clozapina/efectos adversos , Leucopenia/inducido químicamente , Esquizofrenia/tratamiento farmacológico , Adulto , Anciano , Antipsicóticos/uso terapéutico , Biomarcadores/sangre , Clozapina/uso terapéutico , Femenino , Hospitalización , Hospitales Psiquiátricos , Humanos , Incidencia , Recuento de Leucocitos , Leucopenia/sangre , Leucopenia/diagnóstico , Leucopenia/epidemiología , Estudios Longitudinales , Persona de Mediana Edad , Neutrófilos/metabolismo , Estudios Retrospectivos
10.
Nutr Hosp ; 35(Spec No1): 1-9, 2018 03 07.
Artículo en Español | MEDLINE | ID: mdl-29565627

RESUMEN

Eating disorders (ED) are characterized by persistent changes in eating habits that negatively affect a person's health and psychosocial abilities. They are considered psychiatric disorders, highly variable in their presentation and severity, with a huge impact on nutrition, which conditions various therapeutic approaches within a key multidisciplinary context. A group of experts in nutrition, we decided to set up a task force adscribed to the "Sociedad Española de Nutrición Parenteral y Enteral" (SENPE), which has stated as one of its goals the development of a consensus document to generate a protocol based on the best scientific evidence and professional experience available in order to improve health care in this field.


Asunto(s)
Evaluación Nutricional , Trastornos Nutricionales/terapia , Consenso , Trastornos de Alimentación y de la Ingestión de Alimentos/diagnóstico , Trastornos de Alimentación y de la Ingestión de Alimentos/epidemiología , Trastornos de Alimentación y de la Ingestión de Alimentos/terapia , Humanos , Trastornos Nutricionales/diagnóstico , Trastornos Nutricionales/epidemiología , Terapia Nutricional , Apoyo Nutricional , Educación del Paciente como Asunto
11.
Nutr Hosp ; 35(Spec No1): 11-48, 2018 03 07.
Artículo en Español | MEDLINE | ID: mdl-29565628

RESUMEN

Anorexia nervosa is the most common psychiatric disease among young women and it is assumed to be of multifactorial origin. Diagnostic criteria have recently been modified; therefore amenorrhea has ceased to be a part of them. This disease shows a large variability in its presentation and severity which conditions different therapeutic approaches and the need to individualize the treatment, thus it is indispensable a multidisciplinary approach. The goals are to restore nutritional status (through an individualized diet plan based on a healthy consumption pattern), treat complications and comorbidities, nutritional education (based on healthy eating and nutritional patterns), correction of compensatory behaviors and relapse prevention. The treatment will vary according to the patient's clinical situation, and it may be performed in outpatient clinics (when there is clinical stability), in a day hospital or ambulatory clinic (intermediate mode between traditional outpatient treatment and hospitalization) or hospitalization (when there is outpatient management failure or presence of serious medical or psychiatric complications). Artificial nutrition using oral nutritional supplements, enteral nutrition and exceptionally parenteral nutrition may be necessary in certain clinical settings. In severely malnourished patients the refeeding syndrome should be avoided. Anorexia nervosa is associated with numerous medical complications which determines health status, life quality, and is closely related to mortality. There is little clinical evidence to assess the results of different treatments in anorexia nervosa, when most of the recommendations are being based on expert consensus.


Asunto(s)
Anorexia Nerviosa/dietoterapia , Evaluación Nutricional , Terapia Nutricional/métodos , Adolescente , Anorexia Nerviosa/complicaciones , Anorexia Nerviosa/epidemiología , Anorexia Nerviosa/psicología , Consenso , Femenino , Humanos , Masculino , Estado Nutricional , Medicina de Precisión , Síndrome de Realimentación/terapia , Adulto Joven
12.
Nutr Hosp ; 35(Spec No1): 49-97, 2018 Mar 07.
Artículo en Español | MEDLINE | ID: mdl-29565629

RESUMEN

Bulimia nervosa and binge eating disorder are unique nosological entities. Both show a large variability related to its presentation and severity which involves different therapeutic approaches and the need to individualize the treatment, thus it is indispensable a multidisciplinary approach. Patients with bulimia nervosa may suffer from malnutrition and deficiency states or even excess weight, while in binge eating disorders, it is common overweight or obesity, which determine other comorbidities. Many of the symptoms and complications are associated with compensatory behaviors. There are many therapeutic tools available for the treatment of these patients. The nutritional approach contemplates the individualized dietary advice which guarantees an adequate nutritional state and nutritional education. Its objective is to facilitate the voluntary adoption of eating behaviors that promote health and allow the long-term modification of eating habits and the cessation of purgatory and bingeing behaviors. Psychological support is a first-line treatment and it must address the frequent disorder of eating behavior and psychiatric comorbidities. Psychotropic drugs are effective and widely used although these drugs are not essential. The management is carried out mainly at an outpatient level, being the day hospital useful in selected patients. Hospitalization should be reserved to correct serious somatic or psychiatric complications or as a measure to contain non-treatable conflict situations. Most of the guidelines' recommendations are based on expert consensus, with little evidence which evaluates clinical results and cost-effectiveness.


Asunto(s)
Trastorno por Atracón/terapia , Bulimia Nerviosa/terapia , Evaluación Nutricional , Terapia Nutricional/métodos , Adulto , Trastorno por Atracón/diagnóstico , Trastorno por Atracón/epidemiología , Trastorno por Atracón/psicología , Bulimia Nerviosa/complicaciones , Bulimia Nerviosa/diagnóstico , Bulimia Nerviosa/psicología , Consenso , Femenino , Guías como Asunto , Humanos
13.
J Nephrol ; 20(5): 626-8, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17918150

RESUMEN

Glomerulonephritis rarely appears associated with Hodgkin's disease or non-Hodgkin's lymphoma (NHL). We present a patient with a relapse of a non-Hodgkin's lymphoma which first presented as nephrotic syndrome due to focal segmental glomerulosclerosis (FSGS). This case report discusses the unusual association of non-Hodgkin's lymphoma and focal segmental glomerulosclerosis, as well as the crucial role of positron emission tomography in detecting the relapsing lymphoma.


Asunto(s)
Glomeruloesclerosis Focal y Segmentaria/complicaciones , Linfoma no Hodgkin/diagnóstico por imagen , Síndrome Nefrótico/etiología , Tomografía de Emisión de Positrones , Anciano , Glomeruloesclerosis Focal y Segmentaria/diagnóstico por imagen , Glomeruloesclerosis Focal y Segmentaria/etiología , Glomeruloesclerosis Focal y Segmentaria/patología , Humanos , Linfoma no Hodgkin/complicaciones , Linfoma no Hodgkin/patología , Masculino , Síndrome Nefrótico/diagnóstico por imagen , Síndrome Nefrótico/patología , Recurrencia
14.
Nat Commun ; 8(1): 1602, 2017 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-29150610

RESUMEN

Land-atmosphere exchanges influence atmospheric CO2. Emphasis has been on describing photosynthetic CO2 uptake, but less on respiration losses. New global datasets describe upper canopy dark respiration (R d) and temperature dependencies. This allows characterisation of baseline R d, instantaneous temperature responses and longer-term thermal acclimation effects. Here we show the global implications of these parameterisations with a global gridded land model. This model aggregates R d to whole-plant respiration R p, driven with meteorological forcings spanning uncertainty across climate change models. For pre-industrial estimates, new baseline R d increases R p and especially in the tropics. Compared to new baseline, revised instantaneous response decreases R p for mid-latitudes, while acclimation lowers this for the tropics with increases elsewhere. Under global warming, new R d estimates amplify modelled respiration increases, although partially lowered by acclimation. Future measurements will refine how R d aggregates to whole-plant respiration. Our analysis suggests R p could be around 30% higher than existing estimates.


Asunto(s)
Cambio Climático , Consumo de Oxígeno , Plantas/metabolismo , Árboles/metabolismo , Aclimatación , Atmósfera , Biomasa , Dióxido de Carbono/metabolismo , Clima , Geografía , Calentamiento Global , Modelos Teóricos , Oxígeno/metabolismo , Fotosíntesis , Temperatura
16.
Nutr Hosp ; 33(Suppl 1): 175, 2016 Jun 03.
Artículo en Español | MEDLINE | ID: mdl-27269215

RESUMEN

El síndrome de caquexia cancerosa es responsable de la muerte de un número significativo de pacientes con cáncer. Se caracteriza por la presencia de una ingesta reducida, con inflamación sistémica y un metabolismo alterado. Los enfermos presentan característicamente una progresiva pérdida de peso y de masa muscular, junto a deterioro funcional. La pérdida muscular se debe a la combinación de reducción de la síntesis proteica con aumento de su degradación. Ello conduce tanto a un acortamiento como a una reducción en el área de la fibra muscular. Asimismo, existen datos que apoyan que selectivamente algunos de los tipos de fibra muscular se ven más afectados. Es necesario definir bien los valores de corte de sarcopenia para diagnosticar la pérdida muscular y existen diferentes métodos. El sistema de la ubiquitina-proteasoma parece desempeñar un papel predominante en la degradación de la proteína miofibrilar. La tendencia a perder masa muscular en los pacientes con caquexia cancerosa parece estar asociada a la activación de señales catabólicas por citoquinas proinflamatorias, así como por productos tumorales del tipo factor inductor de proteólisis. En referencia a los factores pronósticos, el riesgo de muerte está bien documentado en pacientes con sarcopenia y, especialmente, en aquellos con obesidad asociada a la sarcopenia. Asimismo, se ha establecido una relación directa entre la pérdida intensa de masa muscular y la supervivencia en pacientes con diferentes tipos de tumores del tipo de cáncer de páncreas, pulmón, tracto biliar o cáncer colorrectal. Respecto de la terapia en el síndrome de caquexia cancerosa, es factible que requiera tratamiento con varios grupos combinados que incluyan, junto al soporte nutricional, fármacos orexígenos, con efecto anabólico y antinflamatorio, asociados a intervenciones que estimulen el ejercicio físico.


Asunto(s)
Caquexia/etiología , Caquexia/mortalidad , Músculo Esquelético/patología , Neoplasias/complicaciones , Neoplasias/mortalidad , Sarcopenia/etiología , Sarcopenia/mortalidad , Caquexia/patología , Humanos , Neoplasias/patología , Sarcopenia/patología , Análisis de Supervivencia , Pérdida de Peso
17.
Nutr Hosp ; 33(3): 275, 2016 Jun 30.
Artículo en Español | MEDLINE | ID: mdl-27513502

RESUMEN

BACKGROUND AND AIM: The prevalence of hospital malnutrition (HM) is variable, explained by the variability of patients, the nutritional evaluation method used among others. The aim is to determine the frequency of malnutrition in hospitals in Latin America, and estimate its association with mortality and length of hospital stay. METHODS: This is an analytical, observational cohort study that included 7,973 patients of both genders, 18 and older, who provided their consent. The survey was administered during the first three days of admission. The nutritional status was estimated using Subjective Global Assessment (SGA) and the Nutrition Risk Screening (NRS), body mass index (BMI), percentage of change of weight (PCW) and co-morbidities. Serum albumin was obtained from the clinical chart. Length of stay (LOS) and the survival status at discharge (dead or alive) were also recorded. RESULTS: By SGA: 10.9% had severe malnutrition and 34% moderate malnutrition. By NRS: 36.9% had nutritional risk. Univariate analysis showed that NRS score and serum albumin were prognostic factors for mortality: NRS 3-4 (OR: 2.3, 95% CI: 1.9-2.8), NRS 5-7 (OR: 5.8, 95% CI: 4.9-6.9), serum albumin < 2.5 g/dl, (OR: 2.9, 95% CI: 2.2-3.8). These results were consistent and similar to a multivariate analysis. Both NRS and serum albumin were also independently and clinically associated to LOS. CONCLUSIONS: The prevalence of hospital malnutrition in Latin America is high. Our results show that screening with NRS and serum albumin can identify hospital malnutrition as well as providing clinically relevant prognostic value.


Asunto(s)
Evaluación Nutricional , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Hospitalización , Humanos , América Latina , Tiempo de Internación , Masculino , Desnutrición/epidemiología , Persona de Mediana Edad , Pacientes , Prevalencia , Pronóstico , Adulto Joven
18.
Nutr Hosp ; 32(5): 2346-52, 2015 Nov 01.
Artículo en Español | MEDLINE | ID: mdl-26545697

RESUMEN

INTRODUCTION: although there are precise and accurate techniques for estimating resting energy expenditure, like the indirect calorimetry (IC), daily practice needs faster, easier and cheaper methods as the predictive equations. OBJECTIVE: the aim of the study was to develop a new predictive equation for estimating resting energy expenditure (REE) for healthy Spanish population. Méthods: the REE of 95 healthy normal weighted volunteers was determined by indirect calorimetry (IC). The new equation was obtained by multiple lineal regression by using the analytical criteria of the Cp of Mallows and the adjusted R2. Then, the behavior of the new formula was studied in a group of overweight volunteers through the intraclass correlation coefficient (ICC) and Bland-Almand plots. The level of signification was reached at p < 0,05. RESULTS: the average age was 42 years (range: 2.0-63.2). Mean REE determined by IC was 1 589.1 kcal/d (312.0). The selected equation was: [y = 1 376.4 - 308 Sex (M = 0; W = 1) + 11.1 Weigh (kg) - 8 Age (years)] (R2: 0.68; EE: 175.95). The ICC between the new equation and the IC in normal weighted subjects was 0.901 (95%CI: 0.851 - 0.934). The new formula showed a good level of agreement in the overweight group (ICC: 0.880; 95%IC: 0.772 - 0.937). CONCLUSIONS: we propose a new predictive equation for estimating the REE for healthy Spanish population which has an easy application and includes sex, age and weigh. The selected equation shows an adequate behavior in overweight subjects too.


Introducción: aunque se dispone de técnicas precisas y exactas para la estimación del GER, como la calorimetría indirecta (CI), en la práctica diaria se precisan métodos rápidos, fáciles de aplicar y económicos, como los modelos predictivos. Objetivo: desarrollar una nueva ecuación predictiva del gasto energético en reposo (GER) para población española adulta sana. Métodos: se determinó el GER en 95 sujetos sanos con normopeso mediante CI. Se utilizó la regresión lineal múltiple para la obtención del modelo, empleando como criterios analíticos la Cp de Mallows y el R2 ajustado. Se estudió el comportamiento del modelo generado en una muestra de 39 sujetos con IMC ≥ 25 kg/m2 mediante el coeficiente de correlación intraclase (ICC) y la prueba de Bland-Altman. La significación se alcanzó con p < 0,05. Resultados: la edad media fue de 42 años (rango: 23,0­ 63,2). El valor medio del GER estimado fue de 1.589,1 kcal/d (312,0). La ecuación seleccionada fue: [GER (kcal/d) = 1.376,4 ­ 308 Sexo (V = 0; M = 1) + 11,1 Peso (kg) ­ 8 Edad (años)] (R2: 0,68; EE: 175,95). El CCI entre el nuevo modelo predictivo y la CI fue de 0,901 (IC del 95%: 0,851 ­ 0,934) en la muestra con normopeso. La aplicación del modelo en la muestra de sujetos con IMC ≥ 25 kg/m2 alcanzó una buena concordancia (CCI de 0,880; IC del 95%: 0,772 ­ 0,937). Conclusiones: se presenta un nuevo modelo de estimación del GER para población sana española fácilmente aplicable en la práctica diaria, que incluye las variables sexo, edad y peso. La ecuación propuesta presenta un comportamiento adecuado en sujetos con IMC ≥ 25 kg/m2.


Asunto(s)
Algoritmos , Metabolismo Energético/fisiología , Descanso/fisiología , Adolescente , Adulto , Calorimetría Indirecta , Niño , Preescolar , Femenino , Voluntarios Sanos , Humanos , Masculino , Persona de Mediana Edad , Valores de Referencia , Reproducibilidad de los Resultados , España , Adulto Joven
19.
Adv Mater ; 27(26): 3894-9, 2015 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-26010071

RESUMEN

The origin of the 2D electron gas (2DEG)stabilized at the bare surface of SrTiO3 (001) is investigated. Using high-resolution angle-resolved photoemission and core-level spectroscopy, it is shown conclusively that this 2DEG arises from light-induced oxygen vacancies. The dominant mechanism driving vacancy formation is identified, allowing unprecedented control over the 2DEG carrier density.

20.
Nutr Hosp ; 32(2): 888-96, 2015 Aug 01.
Artículo en Español | MEDLINE | ID: mdl-26268125

RESUMEN

OBJECTIVE: the aim of this study was to analyze the agreement between the resting energy expenditure (REE) obtained by indirect calorimetry (IC) and that obtained by prediction equations in a sample of healthy adults from Spain. Méthods: a descriptive cross-sectional study was conducted in 95 healthy, normal-weight adults. REE was determined by IC and 45 population-specific prediction equations which were based on weight, height, sex and/or body composition (BC). The Intraclass Correlation Coefficient (ICC) and Bland-Alman plots were used to analyze the agreement between the REE obtained by IC and that obtained by prediction equations. The level of signification was reached at p < 0,05. RESULTS: mean age was 42 years (range: 23.0-63.2). Mean REE determined by CI was 1589 (312) kcal/d [1822.3 (224.3) kcal/d in men and 1379.3 (216.1) kcal/d in women; p < 0.05]. The De-Lorenzo, Harris-Benedict, Schofield, and especially the Korth equations showed the greatest level of agreement with respect to IC. CONCLUSIONS: there is high variability in the estimates of REE depending on the prediction equation used. The De Lorenzo, Harris-Benedict, and the Schofield equations showed a good level of agreement in our sample; however, the Korth equation was the most appropriate. Equations based on weight and/or height were more accurate than those which included body composition variables.


Objetivo: estudiar la concordancia entre el gasto energético en reposo (GER) obtenido mediante calorimetría indirecta (CI), y las ecuaciones de estimación más utilizadas en población adulta sana española. Métodos: estudio transversal en el que se determinó el GER en 95 sujetos sanos con normopeso mediante calorimetría indirecta y modelos predictivos (se seleccionaron 45 fórmulas desarrolladas en adultos de características similares a la muestra estudiada que incluían peso, talla, sexo y/o composición corporal). La concordancia entre ambos métodos se analizó mediante el Coeficiente de Correlación Intraclase (CCI) y la prueba de Bland-Altman. La significación se alcanzó con p < 0,05. Resultados: la edad media fue de 42 años (rango: 23,0­ 63,2). El GER medio estimado por CI en la muestra fue de 1589 (312) kcal/día [1822,3 (224,3) kcal/día en varones y 1379,3 (216,1) kcal/día en mujeres; p < 0,05]. Las fórmulas que mejor se ajustaron a la muestra fueron las de De-Lorenzo, Harris-Benedict, Schofield y, especialmente, Korth. Conclusiones: existen grandes variaciones en la estimación del gasto energético en reposo en función de la ecuación predictiva utilizada. Las fórmulas de De-Lorenzo, Harris-Benedic y Schofield se comportan adecuadamente en la muestra evaluada; sin embargo, la de Korth demostró ser la más apta. Los modelos que incluyen peso y/o talla obtuvieron mejores resultados que los que contienen variables de composición corporal.


Asunto(s)
Calorimetría Indirecta , Metabolismo Energético , Adulto , Calorimetría Indirecta/métodos , Estudios Transversales , Femenino , Voluntarios Sanos , Humanos , Masculino , Persona de Mediana Edad , Descanso , España/epidemiología , Adulto Joven
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