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1.
Nano Lett ; 22(21): 8541-8549, 2022 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-36287197

RESUMEN

Addressable quantum states well isolated from the environment are of considerable interest for quantum information science and technology. Carbon nanotubes are an appealing system, since a perfect crystal can be grown without any missing atoms and its cylindrical structure prevents ill-defined atomic arrangement at the surface. Here, we develop a reliable process to fabricate compact multielectrode circuits that can sustain the harsh conditions of the nanotube growth. Nanotubes are suspended over multiple gate electrodes, which are themselves structured over narrow dielectric ridges to reduce the effect of the charge fluctuators of the substrate. We measure high-quality double- and triple-quantum dot charge stability diagrams. Transport measurements through the triple-quantum dot indicate long-range tunneling of single electrons between the left and right quantum dots. This work paves the way to the realization of a new generation of condensed-matter devices in an ultraclean environment, including spin qubits, mechanical qubits, and quantum simulators.

2.
Prev. tab ; 24(2): 60-66, April/June 2022. graf, tab
Artículo en Español | IBECS | ID: ibc-208050

RESUMEN

Objetivo.Existe poca información actualizada sobre el consumo de tabaco durante el embarazo. El objetivo de este trabajo fue determinar la prevalencia de tabaquismo durante el embarazo en mujeres que se atienden en los distintos centros de salud dentro del Área de Gestión Sanitaria Jerez, costa noreste y sierra de Cádiz. Material y método.Estudio transversal mediante entrevistas de gestantes captadas en la visita realizada durante el primer trimestre del embarazo. El cuestionario incluía preguntas sobre características sociode mográficas, edad, antecedentes obstétricos, consumo de tabaco anterior al embarazo y abandono durante la gestación, así como hábito tabáquico en la pareja. Resultados. Se obtuvieron respuestas de 1.173 pacientes con edad media de 31 años. Se confesaron fumadoras activas el 31,2% de ellas, siendo exfumadoras el 9,5% y nunca fumadoras el 59,3%. El consumo medio de cigarrillos fue de 11 ± 7 diarios. Al conocer su estado de gestación dejaron su hábito el 50,8% (abandono espontáneo, n = 186). El porcentaje de fumadora durante la gestación asciende a un 15,5% del global,con un consumo medio de cigarrillos de 5 ± 4/día. En cuanto a las parejas el porcentaje de fumadores activos fue del 41,4%. Aunque solo un 12,4% de estas parejas refirieron seguir fumando en el domicilio conyugal,únicamente el 2,07 % consiguió cesar el consumo por completo. La prevalencia de tabaquismo respecto a un estudio previo en 2009 se redujo significativamente (18,9vs. 15,5 %, p < 0,009).Conclusión.Fumar durante el embarazo sigue siendoun comportamiento frecuente en nuestra área sanitaria. A pesar de que las gestantes reducen su consumo, solo la mitad abandona por completo su hábito. Este comportamiento es muy inferior si consideramos a sus parejas, donde el porcentaje de cesación es ínfimo. (AU)


Objetive. There is little up-to-date information on tobacco 11 use during pregnancy. The objective of this work was to determine the prevalence of smoking during pregnancy in women who are cared for in the different Health Centers within the Jerez Health Management Area, northeast coast and sierra of Cadiz. Material and method. Cross-sectional study through interviews of pregnant women enrolled duringthe visit during the first trimester of pregnancy. The questionnaire included questions about sociodemo-graphic characteristics, age, obstetric history, tobacco consumption prior to pregnancy and cessation during pregnancy, as well as smoking habits in the couple. Results. Responses were obtained from 1,173 patients,with a mean age of 31 years. 31.2% of them confessed to being active smokers, 9.5% being ex-smokers and 59.3% never smokers. The average consumption ofcigarettes was 11 ± 7 per day. When knowing theirstate of pregnancy, 50.8% of them quit their habit(spontaneous quitters, n = 186). The percentage ofsmokers during pregnancy amounts to 15.5% of theglobal with an average cigarette consumption of 5 ±4/day. As for couples, the percentage of active smokerswas 41.4%. Although only 12.4% of these couples reported continuing to smoke at their marital home,only 2.07% managed to stop using them completely.The prevalence of smoking compared to a previousstudy in 2009 was significantly reduced (18.9 vs.15.5%, p < 0.009).Conclusion.Smoking during pregnancy continues tobe a frequent behavior in our healthcare area. Despitethe fact that pregnant women reduce their consump-tion, only half abandon their habit completely. Thisbehavior is much lower if we consider their partnerswhere the percentage of cessation is negligible. (AU)


Asunto(s)
Humanos , Femenino , Tabaquismo/prevención & control , Tabaquismo/terapia , Mujeres Embarazadas , Cese del Uso de Tabaco/estadística & datos numéricos , Estudios Transversales , Entrevistas como Asunto
3.
Eval Program Plann ; 68: 81-89, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29499470

RESUMEN

This observational study intends to estimate the causal effects of an English as a Medium of Instruction (EMI) program (as predictor) on students Grade Point Average (GPA) (as outcome) at a particular University in Spain by using a Counterfactual Impact Evaluation (CIE). The need to address the crucial question of causal inferences in EMI programs to produce credible evidences of successful interventions contrasts, however, with the absence of experimental or quasi-experimental research and evaluation designs in the field. CIE approach is emerging as a methodologically viable solution to bridge that gap. The program evaluated here consisted in delivering an EMI program in a Primary Education Teacher Training Degree group. After achieving balance on the observed covariates and recreating a situation that would have been expected in a randomized experiment, three matching approaches such as genetic matching, nearest neighbor matching and Coarsened Exact Matching were used to analyze observational data from a total of 1288 undergraduate students, including both treatment and control group. Results show unfavorable effects of the bilingual group treatment condition. Potential interpretations and recommendations are provided in order to strengthen future causal evidences of bilingual education programs' effectiveness in Higher Education.


Asunto(s)
Éxito Académico , Multilingüismo , Evaluación de Programas y Proyectos de Salud , Universidades/organización & administración , Femenino , Humanos , Masculino , Factores Sexuales , Factores Socioeconómicos , España , Abandono Escolar , Universidades/normas , Adulto Joven
4.
Arch Physiol Biochem ; 105(2): 144-50, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9255398

RESUMEN

The effect of age on the exocrine pancreatic function was studied in fifteen Granadina goat kids during the second, third and fourth postnatal week. The animals, chronically catheterized, were bottle-fed on goat milk twice a day. Pure pancreatic juice was collected from 1 hour before and throughout 8 hours after milk ingestion. Pancreatic flow rate, bicarbonate and chloride concentrations, total protein content and enzyme activities were determined. In resting conditions, pancreatic flow rate augmented with age, probably reflecting an increase in body and pancreas weight. Resting amylase and lipase activities recorded significant increases during the fourth week of life. That may be associated, respectively, to the immediate change to a high-starch diet and to a simultaneous decrease in the salivary lipase levels. Our results also showed age-related differences after ingestion of milk, mainly concerning the volume response and the lipase output. The latter can be explained in the same way as regarding resting conditions. With respect to the volume response, several factors could be implicated, such as the circulating levels of gastrointestinal hormones, the sensitivity of the pancreas to such stimuli, the maturation degree in the secretory mechanisms of the gland or the development of the digestive tract.


Asunto(s)
Envejecimiento/metabolismo , Cabras/metabolismo , Páncreas/metabolismo , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Cabras/crecimiento & desarrollo , Leche/metabolismo , Jugo Pancreático/química , Jugo Pancreático/metabolismo
5.
Arch Physiol Biochem ; 105(2): 190-6, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9255404

RESUMEN

Suckling goats were fed ad libitum during the first month of their life by goat milk or by a milk replacer. These diets differed in the amount of fat and the type of protein. The composition of the exocrine pancreatic secretion in the basal period and in response to food were compared in both conditions. Pancreatic juice was collected one hour before meal intake up to the 8th postprandial hour. Pancreatic flow rate, bicarbonate and chloride levels, total protein and enzyme activities were measured. In resting conditions and in response to food, the lipase activity was found to be significantly lower in the group fed with milk replacer, which was poorer in fat. These results indicate an adaptation of the enzyme output to the available quantity of its substrate, similar to that described in the rat. Postprandial differences in the pancreatic flow rate, electrolytes and total protein were found between both groups. Their origin can be attributed to the protein used (soyabean) in the milk substitute. Such soya protein alters the normal clot formation in the abomasum and allows an accelerated abomasal digesta outflow and duodenal pH alkalinisation.


Asunto(s)
Adaptación Fisiológica , Cabras/metabolismo , Leche/metabolismo , Páncreas/metabolismo , Amilasas/metabolismo , Animales , Animales Lactantes , Quimotripsina/metabolismo , Cabras/crecimiento & desarrollo , Lipasa/metabolismo , Jugo Pancreático/enzimología , Jugo Pancreático/metabolismo , Periodo Posprandial
6.
Br Vet J ; 152(6): 673-82, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8979425

RESUMEN

The post-natal composition of biliary lipids in the bile of suckling goat kids has been studied during the first month of life. Samples of hepatic and vesicular bile were obtained from animals fed with milk. Bile flow increased with age and the concentration of bile acids also rose up to 14 days of age. Cholesterol reached maximum values immediately after birth and then decreased. Bile acids conjugated with taurine predominated and this pattern of preferential tauroconjugation persisted at all ages, as has also been found in carnivores and sheep. Comparison of vesicular and hepatic bile composition revealed a poor concentration capacity of the gallbladder in pre-ruminant kids.


Asunto(s)
Envejecimiento/metabolismo , Animales Recién Nacidos/metabolismo , Bilis/metabolismo , Cabras/metabolismo , Metabolismo de los Lípidos , Animales , Bilis/química , Ácidos y Sales Biliares/análisis , Ácidos y Sales Biliares/metabolismo , Colesterol/análisis , Colesterol/metabolismo , Calostro , Vesícula Biliar/química , Vesícula Biliar/metabolismo , Vesícula Biliar/fisiología , Cabras/fisiología , Lípidos/análisis , Hígado/química , Hígado/metabolismo , Hígado/fisiología , Leche , Fosfolípidos/análisis , Fosfolípidos/metabolismo , Distribución Aleatoria , Taurina/análisis , Taurina/metabolismo
7.
Br Vet J ; 152(4): 433-9, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8791851

RESUMEN

A reversed-phase high performance liquid chromatography technique has been developed for the identification of taurine- and glycine-conjugated bile acids in the bile of preruminant goats. The mobile phase consisted of two solvents: acetonitrile (A) and 5 mM potassium phosphate buffer (pH 4.5) (B). Samples (10 microliters) were eluted with a linear gradient in which acetonitrile was increased from 25 to 35%, and from 35 to 45%, at 10 min intervals. Flow rate was 1.0 ml min-1, and bile acids were detected at 200 nm. This sample high resolution technique was highly reproducible, involved a minimum of straightforward sample treatment, and required a short chromatographic development time. The technique will be of use in the systematic identifications of bile acids in preruminants.


Asunto(s)
Ácidos y Sales Biliares/análisis , Bilis/química , Glicina/metabolismo , Cabras/metabolismo , Taurina/metabolismo , Acetonitrilos , Animales , Bilis/metabolismo , Ácidos y Sales Biliares/metabolismo , Tampones (Química) , Cromatografía Líquida de Alta Presión/métodos , Cromatografía Líquida de Alta Presión/veterinaria , Fosfatos , Compuestos de Potasio
8.
Arch Physiol Biochem ; 104(2): 239-45, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8818210

RESUMEN

A total of 45 preruminant goats were fed either goat milk or a milk substitute. The postnatal development of bile secretion and biliary lipids composition of suckling goats and the influence upon these parameters of maternal milk substitution were studied during the first month of life. Samples of hepatic and gallbladder bile were obtained from kids of 1, 7, 14, 21 and 28 day-old. Bile flow rate, cholesterol, total bile salts and phospholipids were measured. Our results show that the quality of the protein and fat used in the elaboration of the milk replacer, affects the evolution of both hepatic bile flow and biliary lipids composition. Differences between gallbladder and hepatic bile composition show a scarce concentration capacity of the gallbladder with both diets and at all ages studied.


Asunto(s)
Bilis/metabolismo , Cabras/fisiología , Metabolismo de los Lípidos , Leche , Animales , Animales Lactantes , Vesícula Biliar/metabolismo , Cabras/metabolismo , Distribución Aleatoria , Tasa de Secreción , Ovinos
9.
Arch Physiol Biochem ; 104(2): 246-51, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8818211

RESUMEN

A total of 45 preruminant goats were fed either goat milk or a milk substitute to compare the evolution of taurine and glycine conjugated bile acids and the evolution of the intestinal flora during the first month of life. Samples of hepatic bile were obtained from kids of 1, 7, 14, 21, and 28 days old and conjugated bile acids were measured by high performance liquid chromatography. Bacterial flora were determined in 14 and 28 day old animals. Ours results show that under our experimental conditions tauroconjugated bile acids clearly predominated over the conjugated with glycine. This pattern of preferential tauroconjugation persisted at all ages tested and in both groups studied. On the other hand, it seems that the quality of the protein and fat used in the elaboration of the milk replacer affects the intestinal flora and the postnatal evolution of conjugated bile acids.


Asunto(s)
Ácidos y Sales Biliares/análisis , Glicina/análisis , Cabras/metabolismo , Intestinos/microbiología , Leche , Taurina/análisis , Animales , Animales Lactantes , Ácidos y Sales Biliares/química , Ovinos
10.
Rev. Finlay ; 3(2/3): 68-76, abr.- sept. 1989.
Artículo en Español | LILACS | ID: lil-246115

RESUMEN

A fin de investigar los criterios que tienen los estudiantes de medicina de la Facultad de Ciencias Médicas de Cienfuegos, que reciben docencia en el hospial provincial clínico quirúrgico "Dr. Gustavo Aldereguía Lima" sobre la existencia de yatrogénia psicológica, se seleccionó una muestra aleatoria suficientemente representativa que ascendió a 127 estudiantes de tercero hasta quinto año de dicha carrera, luego de tabular los resultados, se calcularon los porcientos y se representaron mediante tablas y gráficos


Asunto(s)
Enfermedad Iatrogénica/epidemiología
11.
Rev Esp Fisiol ; 42(4): 489-95, 1986 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3563075

RESUMEN

Saliva secretion in response to the stimulation of the superior cervical ganglion (S.C.G.) at different frequencies (2, 3, 5, 10, 15, 20 Hz) has been studied in anaesthetized rabbits. The differences between the two major glands in this species were analyzed, with respect to the flow response, potassium, amylase and total protein content during the sympathetic stimulation. The stimulation of S.C.G. increased the salivary flow rate at all frequencies, on both parotid and mandibular gland. In the parotid gland the flow and stimulation frequency show a positive linear correlation which does not appear in the mandibular gland. In conclusion, the differences observed in the response to sympathetic stimulation in both glands seem to be due to distinct patterns of sympathetic innervation on different glandular elements.


Asunto(s)
Ganglios Simpáticos/fisiología , Glándula Parótida/fisiología , Conejos/fisiología , Salivación , Glándula Submandibular/fisiología , Animales , Estimulación Eléctrica
12.
Lab Anim ; 20(3): 231-3, 1986 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3795860

RESUMEN

A new surgical procedure for the study of pancreatic secretion in the conscious preruminant goat, under conditions which approach physiological normality, is described. The bile and pancreatic juice retain their natural route and preserve the normal function of the sphincter of Oddi. Experiments could be started 3 days after surgery.


Asunto(s)
Cabras/cirugía , Páncreas/cirugía , Jugo Pancreático/metabolismo , Animales
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