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1.
Sensors (Basel) ; 16(10)2016 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-27669241

RESUMO

The use of massive multiple-input multiple-output (MIMO) techniques for communication at millimeter-Wave (mmW) frequency bands has become a key enabler to meet the data rate demands of the upcoming fifth generation (5G) cellular systems. In particular, analog and hybrid beamforming solutions are receiving increasing attention as less expensive and more power efficient alternatives to fully digital precoding schemes. Despite their proven good performance in simple setups, their suitability for realistic cellular systems with many interfering base stations and users is still unclear. Furthermore, the performance of massive MIMO beamforming and precoding methods are in practice also affected by practical limitations and hardware constraints. In this sense, this paper assesses the performance of digital precoding and analog beamforming in an urban cellular system with an accurate mmW channel model under both ideal and realistic assumptions. The results show that analog beamforming can reach the performance of fully digital maximum ratio transmission under line of sight conditions and with a sufficient number of parallel radio-frequency (RF) chains, especially when the practical limitations of outdated channel information and per antenna power constraints are considered. This work also shows the impact of the phase shifter errors and combiner losses introduced by real phase shifter and combiner implementations over analog beamforming, where the former ones have minor impact on the performance, while the latter ones determine the optimum number of RF chains to be used in practice.

2.
Nat Commun ; 14(1): 6962, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37907508

RESUMO

Changing the perception of defects as imperfections in crystalline frameworks into correlated domains amenable to chemical control and targeted design might offer opportunities for the design of porous materials with superior performance or distinctive behavior in catalysis, separation, storage, or guest recognition. From a chemical standpoint, the establishment of synthetic protocols adapted to control the generation and growth of correlated disorder is crucial to consider defect engineering a practicable route towards adjusting framework function. By using UiO-66 as experimental platform, we systematically explored the framework chemical space of the corresponding defective materials. Periodic disorder arising from controlled generation and growth of missing cluster vacancies can be chemically controlled by the relative concentration of linker and modulator, which has been used to isolate a crystallographically pure "disordered" reo phase. Cs-corrected scanning transmission electron microscopy is used to proof the coexistence of correlated domains of missing linker and cluster vacancies, whose relative sizes are fixed by the linker concentration. The relative distribution of correlated disorder in the porosity and catalytic activity of the material reveals that, contrarily to the common belief, surpassing a certain defect concentration threshold can have a detrimental effect.

3.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1447183

RESUMO

En el embarazo el requerimiento energético y de nutrientes aumentan, el déficit o el exceso puede afectar el estado nutricional de la madre y del neonato. Con el objetivo de determinar la frecuencia de malnutrición y su relación con complicaciones en mujeres embarazadas y sus recién nacidos que acuden al Hospital Distrital de Capiatá del Ministerio de Salud Pública y Bienestar Social, en el mes de febrero a agosto de 2022, se realizó un estudio observacional descriptivo de corte transverso retrospectivo que incluyó a 140 gestantes, de las cuales 64 presentaron complicaciones por malnutrición y 76 no presentaron ninguna complicación. La edad media fue de 26,9±6,6 años con un rango de edad de 15 a 40 años. Los resultados muestran que el 45.7% (n=64) de las gestantes presentaron complicaciones por malnutrición, el 51,6% presentó diabetes gestacional, anemia en el 29,7%, el 7,8% presentó anemia y diabetes gestacional, el otro 7,8% hipertensión arterial, el 1,6% manifestó hipertensión arterial y diabetes gestacional y el otro 1,6% presentó anemia, hipertensión arterial y diabetes gestacional. En relación a la evaluación nutricional al inicio y al final de la gestación en las gestantes con complicaciones hubo una leve disminución en los porcentajes de obesidad de 43,7% a 37,5% y un aumento del bajo peso de 11% a 20,3%. En cuanto al tipo de parto en las gestantes con complicaciones el 51,6% fue por cesárea (n=33), las cuales presentaron diabetes gestacional en el 54,5%, seguido de anemia en el 21,2%. Se comprobó un mayor porcentaje de sobrepeso y obesidad (29,7%) en los recién nacidos de madres con complicaciones. Se pudo evidenciar la frecuencia de malnutrición y complicaciones en casi la mitad de las gestantes, es preciso generar mayores estrategias en salud pública para prevenir la malnutrición y complicaciones en gestantes.


In pregnancy the energy and nutrient requirement increases, the deficit or excess can affect the nutritional status of the mother and the neonate. In order to determine the frequency of malnutrition and their relationship with complications in pregnant women and their newborns who go to the Capiata District Hospital of the Ministry of Public Health and Social Welfare, in the month of February to August 2022, a Descriptive observational study of retrospective cross -section that included 140 pregnant women, of which 64 presented complications for malnutrition and 76 did not present any complication. The Middle Ages was 26.9 ± 6.6 years with an age range of 15 to 40 years. The results show that 45.7% (n = 64) of pregnant women presented complications for malnutrition, 51.6% presented gestational diabetes, anemia in 29.7%, 7.8% presented anemia and gestational diabetes, the other 7.8% arterial hypertension, 1.6% expressed arterial hypertension and gestational diabetes and the other 1.6% presented anemia, arterial hypertension and gestational diabetes. In relation to nutritional evaluation at the beginning and at the end of pregnancy in pregnant women with complications there was a slight decrease in obesity percentages of 43.7% to 37.5% and an increase in low weight of 11% to 20, 3%. As for the type of childbirth in pregnant women with complications, 51.6%was due to caesarean section (n = 33), which presented gestational diabetes in 54.5%, followed by anemia in 21.2%. A higher percentage of overweight and obesity (29.7%) was proven in mother's newborns with complications. The frequency of malnutrition and complications could be evidenced in almost half of the pregnant women, it is necessary to generate greater public health strategies to prevent malnutrition and complications in pregnant women.

4.
An. Fac. Cienc. Méd. (Asunción) ; 56(2): 35-45, 20230801.
Artigo em Espanhol | LILACS | ID: biblio-1444978

RESUMO

En el embarazo el requerimiento energético y de nutrientes aumentan, el déficit o el exceso puede afectar el estado nutricional de la madre y del neonato. Con el objetivo de determinar la frecuencia de malnutrición y su relación con complicaciones en mujeres embarazadas y sus recién nacidos que acuden al Hospital Distrital de Capiatá del Ministerio de Salud Pública y Bienestar Social, en el mes de febrero a agosto de 2022, se realizó un estudio observacional descriptivo de corte transverso retrospectivo que incluyó a 140 gestantes, de las cuales 64 presentaron complicaciones por malnutrición y 76 no presentaron ninguna complicación. La edad media fue de 26,9±6,6 años con un rango de edad de 15 a 40 años. Los resultados muestran que el 45.7% (n=64) de las gestantes presentaron complicaciones por malnutrición, el 51,6% presentó diabetes gestacional, anemia en el 29,7%, el 7,8% presentó anemia y diabetes gestacional, el otro 7,8% hipertensión arterial, el 1,6% manifestó hipertensión arterial y diabetes gestacional y el otro 1,6% presentó anemia, hipertensión arterial y diabetes gestacional. En relación a la evaluación nutricional al inicio y al final de la gestación en las gestantes con complicaciones hubo una leve disminución en los porcentajes de obesidad de 43,7% a 37,5% y un aumento del bajo peso de 11% a 20,3%. En cuanto al tipo de parto en las gestantes con complicaciones el 51,6% fue por cesárea (n=33), las cuales presentaron diabetes gestacional en el 54,5%, seguido de anemia en el 21,2%. Se comprobó un mayor porcentaje de sobrepeso y obesidad (29,7%) en los recién nacidos de madres con complicaciones. Se pudo evidenciar la frecuencia de malnutrición y complicaciones en casi la mitad de las gestantes, es preciso generar mayores estrategias en salud pública para prevenir la malnutrición y complicaciones en gestantes.


In pregnancy the energy and nutrient requirement increases, the deficit or excess can affect the nutritional status of the mother and the neonate. In order to determine the frequency of malnutrition and their relationship with complications in pregnant women and their newborns who go to the Capiata District Hospital of the Ministry of Public Health and Social Welfare, in the month of February to August 2022, a Descriptive observational study of retrospective cross -section that included 140 pregnant women, of which 64 presented complications for malnutrition and 76 did not present any complication. The Middle Ages was 26.9 ± 6.6 years with an age range of 15 to 40 years. The results show that 45.7% (n = 64) of pregnant women presented complications for malnutrition, 51.6% presented gestational diabetes, anemia in 29.7%, 7.8% presented anemia and gestational diabetes, the other 7.8% arterial hypertension, 1.6% expressed arterial hypertension and gestational diabetes and the other 1.6% presented anemia, arterial hypertension and gestational diabetes. In relation to nutritional evaluation at the beginning and at the end of pregnancy in pregnant women with complications there was a slight decrease in obesity percentages of 43.7% to 37.5% and an increase in low weight of 11% to 20, 3%. As for the type of childbirth in pregnant women with complications, 51.6%was due to caesarean section (n = 33), which presented gestational diabetes in 54.5%, followed by anemia in 21.2%. A higher percentage of overweight and obesity (29.7%) was proven in mother's newborns with complications. The frequency of malnutrition and complications could be evidenced in almost half of the pregnant women, it is necessary to generate greater public health strategies to prevent malnutrition and complications in pregnant women.

5.
Dermatology ; 211(3): 267-72, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16205073

RESUMO

The development of xanthomatous changes in lesions of primary cutaneous T-cell lymphomas (CTCL) is a rare event. It is usually observed in regressing skin tumours or plaques spontaneously or after a specific treatment. The pathogenetic mechanisms implicated in these changes are poorly understood. We are reporting 2 cases of extensive dystrophic xanthomatous changes, developing in regressing lesions of primary cutaneous CD30-positive T-cell lymphoproliferative disorders. Previously reported cases of primary CTCL developing secondary (dystrophic) xanthomata are reviewed.


Assuntos
Antígeno Ki-1/imunologia , Linfoma Cutâneo de Células T/terapia , Xantomatose/etiologia , Adulto , Idoso de 80 Anos ou mais , Humanos , Linfoma Cutâneo de Células T/complicações , Linfoma Cutâneo de Células T/imunologia , Masculino
6.
Exp Dermatol ; 14(12): 883-90, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16274455

RESUMO

The aim of the present study was to identify genetic aberrations in a series of patients with cutaneous large B-cell lymphoma (LBCL) using comparative genomic hybridization (CGH). Eighteen consecutive patients with primary (13 patients) (PCLBCL) and secondary (five patients) (SCLBCL) cutaneous large B-cell lymphoma were included in the study. Nine cases corresponded to PCLBCL leg type and four cases primary cutaneous follicle centre-cell lymphoma (PCFCL). Chromosomal imbalances (CIs) were detected in 14 of 18 samples (77.8%). All of nine cases with PCLBCL leg type and two of four cases with PCFCL showed CIs (100% and 50%, respectively). Regarding SCLBCL, in three of five cases (60%), CIs were detected. The most frequently detected gains involved 2q, 5q, 3 and 7q and amplifications affected 18, 12 and 13. Frequent losses were found in 17p. In PCLBCL leg type, the most frequent gains involved 2q and 7q, amplifications were localized in chromosomes 12, 13 and 18 and losses affected chromosomes 17p and 19. In PCFCL, gains located in 3q, 4 and 7q were found. Our study seems to confirm clear-cut differences between primary cutaneous LBCL and nodal diffuse LBCL, and it suggests the presence of genotypic differences between cases of PCLBCL leg type and cases of PCFCL.


Assuntos
Linfoma de Células B/genética , Linfoma Difuso de Grandes Células B/genética , Hibridização de Ácido Nucleico , Neoplasias Cutâneas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Aberrações Cromossômicas , Feminino , Amplificação de Genes , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Linfoma de Células B/metabolismo , Linfoma de Células B/patologia , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia
7.
Rev. esp. salud pública ; 74(2): 163-176, mar. 2000.
Artigo em Es | IBECS (Espanha) | ID: ibc-9672

RESUMO

Fundamento: Siendo la escuela el marco ideal para desarrollar actividades de Educación para la Salud, se pretende detectar y cuantificar los cambios en actitudes y conocimientos de los adolescentes escolarizados en Algemesí (Valencia), tras una intervención educativa sobre la infección por VIH. Método: Se invitó a participar a once centros docentes con 2.599 adolescentes (12-19 años), matriculados en once niveles educativos (Educación Secundaria, Bachillerato Unificado Polivalente, Curso de Orientación Universitaria y Formación profesional). La intervención, Aulasida, desarrollada durante el curso escolar 1996-1997, consistió en una charla-coloquio informativa y actividades participativas en grupos reducidos, con material didáctico. El instrumento de medida fue un cuestionario. Se diseñó un estudio transversal antes-después. Se realizó un análisis estratificado según edad y nivel educativo. Las medias se compararon con la prueba t de Student y los porcentajes de cambio con Chi2. Resultados: Aceptaron participar 9 centros. 1575 alumnos respondieron al pre-test (47,4 por ciento hombres; 52,1 por ciento mujeres), la edad media fue de 15,2 (1,96) años. El promedio de respuestas correctas en el pre-test fue 13,5 (2,8). En el post-test, hubo un aumento global hasta 14,7 (3,0) aciertos (p<0,01). Por niveles educativos, este incremento fue llamativo en el grupo de menor edad. Las fuentes de información sobre la infección por VIH más habituales fueron: televisión (80,8 por ciento), Aulasida (76,8 por ciento), profesores (60,9 por ciento), folletos (58,4 por ciento) y películas (53,7 por ciento).Conclusiones: Las intervenciones educativas son herramientas útiles para incrementar conocimientos y mejorar actitudes sobre la infección por VIH; la escuela secundaria es un buen medio para ello, debiéndose realizar las intervenciones en los grupos más jóvenes, por ser mayor el impacto que se obtiene en ellos (AU)


Assuntos
Criança , Adolescente , Adulto , Masculino , Feminino , Humanos , Atitude Frente a Saúde , Cognição , Soropositividade para HIV , Educação em Saúde , Serviços Preventivos de Saúde , Espanha , Estudos Retrospectivos , Inquéritos e Questionários , Estudos Transversais , Comportamento do Adolescente , Promoção da Saúde , Área Programática de Saúde
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