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1.
Science ; 365(6460): 1441-1445, 2019 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-31604272

RESUMO

Surveys have shown that super-Earth and Neptune-mass exoplanets are more frequent than gas giants around low-mass stars, as predicted by the core accretion theory of planet formation. We report the discovery of a giant planet around the very-low-mass star GJ 3512, as determined by optical and near-infrared radial-velocity observations. The planet has a minimum mass of 0.46 Jupiter masses, very high for such a small host star, and an eccentric 204-day orbit. Dynamical models show that the high eccentricity is most likely due to planet-planet interactions. We use simulations to demonstrate that the GJ 3512 planetary system challenges generally accepted formation theories, and that it puts constraints on the planet accretion and migration rates. Disk instabilities may be more efficient in forming planets than previously thought.

2.
Nature ; 563(7731): 365-368, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30429552

RESUMO

Barnard's star is a red dwarf, and has the largest proper motion (apparent motion across the sky) of all known stars. At a distance of 1.8 parsecs1, it is the closest single star to the Sun; only the three stars in the α Centauri system are closer. Barnard's star is also among the least magnetically active red dwarfs known2,3 and has an estimated age older than the Solar System. Its properties make it a prime target for planetary searches; various techniques with different sensitivity limits have been used previously, including radial-velocity imaging4-6, astrometry7,8 and direct imaging9, but all ultimately led to negative or null results. Here we combine numerous measurements from high-precision radial-velocity instruments, revealing the presence of a low-amplitude periodic signal with a period of 233 days. Independent photometric and spectroscopic monitoring, as well as an analysis of instrumental systematic effects, suggest that this signal is best explained as arising from a planetary companion. The candidate planet around Barnard's star is a cold super-Earth, with a minimum mass of 3.2 times that of Earth, orbiting near its snow line (the minimum distance from the star at which volatile compounds could condense). The combination of all radial-velocity datasets spanning 20 years of measurements additionally reveals a long-term modulation that could arise from a stellar magnetic-activity cycle or from a more distant planetary object. Because of its proximity to the Sun, the candidate planet has a maximum angular separation of 220 milliarcseconds from Barnard's star, making it an excellent target for direct imaging and astrometric observations in the future.

3.
SEMERGEN, Soc. Esp. Med. Rural Gen. (Ed. impr.) ; 32(5): 218-222, mayo 2006. ilus, graf
Artigo em Es | IBECS | ID: ibc-047878

RESUMO

INTRODUCCIÓN. La fotografía digital, la formación continuada a distancia y la universalización de internet son campos de gran proyección en la práctica habitual del médico de familia. OBJETIVO. Creación de una página web de acceso gratuito que ofrezca imágenes médicas de calidad en formato digital. MÉTODO. Se seleccionaron todas aquellas imágenes de la consulta susceptibles de ser de interés docente para el médico de familia. Se diseñó un circuito para la realización de fotografías digitales en dos Áreas Básicas de Salud y un hospital de referencia. Una vez obtenida una casuística importante de imágenes en formato JPEG, se diseñó la forma de la página, la política de privacidad, se buscó un servidor, se registró un dominio, y finalmente se colgó la página en red. RESULTADOS. Se ha creado una página con 1.200 imágenes médicas. Se han recibido más de 600.000 peticiones al servidor en un año, con visitas procedentes de España y varios países de habla hispana. Ha habido una transferencia media diaria de 17,15 megabytes. La mayor afluencia se realiza de martes a viernes (63% del total de visitas), siendo de 10 a 13 y de 15 a 19 las horas de más entradas. CONCLUSIONES. Se ha conseguido crear una página dinámica e interactiva que ofrece libremente múltiples imágenes de interés docente para el médico de familia


INTRODUCTION. Digital photography, correspondence continuous education and universalization of Internet are fields having great projection in the usual practice of the family doctor. OBJECTIVE. Creation of a free access web page that offers medical images of quality in digital format. METHOD. All those images of medical consultation that may have teaching interest for the family doctor were selected. A circuit to perform digital photographs in two basic health areas and a reference hospital were selected. Once an important casuistry of the images in JPEG format was obtained, the page form and privacy policy were designed, a server sought, a domain was registered and finally the page was up-loaded in the net. RESULTS. A page with 1200 medical images has been created. More than 600,000 requests have been received by the server in one year, with visits from Spain and several Spanish speaking countries. There has been a mean daily transference of 17.15 megabytes. The greatest number of visits is from Tuesday to Friday (63% of all the visits), 10 a.m. and 1 p.m. and 3 p.m. to 7 p.m. having the most visits. CONCLUSIONS. It has been possible to create a dynamic and interactive page that freely offers multiple images of teaching interest for the family doctor


Assuntos
Humanos , Atenção Primária à Saúde , Fotografia , Internet , Espanha
8.
Emergencias (St. Vicenç dels Horts) ; 16(5): 178-183, oct. 2004. tab
Artigo em Es | IBECS | ID: ibc-36759

RESUMO

Introducción: La demanda asistencial en los servicios de urgencias hospitalarios (SUH) se ha incrementado. Entre los usuarios, algunos consultan reiteradamente. Son los pacientes hiperfrecuentadores (HF). Objetivos: Describir epidemiológicamente el grupo de pacientes HF Métodos: Estudio descriptivo, retrospectivo y transversal. Los sujetos fueron pacientes atendidos durante 2 años. A través de la base de datos informatizada se dividieron los individuos en dos grupos: HF (>6 visitas en 2 años) y no HF (nHF). Las variables del estudio fueron: edad, sexo, número de pacientes/visitas/ingresos por grupos de edad y sexo, frecuentación y área asistencial responsable del alta. Resultados: Se realizaron 148.939 visitas, de las que el 7,64 por ciento fueron de HF El número de HF responsables de estas fue 1.563 (1,64 por ciento). La media de visitas diarias resultó de 220ñ20: 14,7ñ4,3 eran HF y 184,2ñ19,4 eran nHF. Por sexos, los hombres fueron el 52,23 por ciento de los atendidos (resultaron el 49,5 por ciento de los HF). Por grupos de edad, los HF se distribuyeron en: 80: años el 3,2 por ciento. Los menores de 2 años HF aglutinaron el 55,9 por ciento de las visitas pediátricas. Los HF ingresaron el 12,68 por ciento de las ocasiones (versus el 15,9 por ciento los nHF). Las principales áreas responsables del alta fueron Medicina Interna (42,29 por ciento) y Pediatría (26,46 por ciento). Conclusiones: Los pacientes HF representan un volumen pequeño de la demanda del SUH. Las características de los pacientes varían por edad y sexo, siendo los más frecuentadores los niños varones y las mujeres en edad fértil (AU)


Assuntos
Adolescente , Adulto , Idoso , Feminino , Pré-Escolar , Lactente , Masculino , Pessoa de Meia-Idade , Criança , Humanos , Recém-Nascido , Hospitais de Emergência/estatística & dados numéricos , Sistemas de Comunicação entre Serviços de Emergência/organização & administração , Serviços Médicos de Emergência , Emergências/epidemiologia , Pacientes/estatística & dados numéricos , Pacientes/classificação , Epidemiologia Descritiva , Estudos Retrospectivos , Estudos Transversais
10.
Rev Enferm ; 20(227-8): 73-8, 1997.
Artigo em Espanhol | MEDLINE | ID: mdl-9282081

RESUMO

Principle problems of a basic health care area (Lérida) are identified. This area, which has a patient case load of 22,244 people, was studied during the winter of 1993-94 by using information from various sources. Results indicate that the population of this community are basically young, urban, have a high cultural and social level, and are mostly employed. The principle causes of mortality are the same as in the rest of Cataluña. Diseases that cause the most working days lost to illness are: respiratory, mental and bone-joint problems. The most frequent diseases seen in the clinic are: hypertension, respiratory infections, endocrine and mental. An overall look at the state of health of these patients show that the principle problems are: tobacco use, high blood pressure, arthritis, lumbago, depression, stroke, diabetes and breast cancer.


Assuntos
Centros Comunitários de Saúde/estatística & dados numéricos , Morbidade , Carga de Trabalho , Humanos , Espanha
11.
An Med Interna ; 14(2): 71-5, 1997 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-9206516

RESUMO

The hospital mortality rate in our centre es 2.34% (264 deaths from a total of 11,336 discharges between 1991 and 1993). The most frequent causes are acute myocardial infarction and cerebrovascular accidents, followed in descending order by pneumonia, chronic bronchitis, congestive heart failure, upper GI haemorrhage, GI tumours, liver cirrhosis, lung tumours and arrhythmias. Our analysis reflects a mortality pattern of a rural population with an age pyramid in which 52% of the patients are older than 45 years. The pattern also reflects the little impact of accidents on our mortality. A 87% of the deaths were older than 65 years with a male to female ratio of 1, 6 and a Swaroop index of 93% and 94% for males and females respectively.


Assuntos
Mortalidade Hospitalar/tendências , Adolescente , Adulto , Idoso , Causas de Morte , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , População Rural , Espanha
15.
An Esp Pediatr ; 30(5): 348-52, 1989 May.
Artigo em Espanhol | MEDLINE | ID: mdl-2757301

RESUMO

We studied the effects of antileukemic chemotherapy on the granulomonocytic precursors (CFU-GM) by the in vitro bone marrow culture method. Groups of study were: 1) 17 children with acute lymphoblastic leukemia in complete remission, under maintenance chemotherapy, and 2) 10 children who had finished the treatment. Both groups had the same treatment schedule. As a control group, we studied CFU-GM from 3 children without bone marrow lesion. The results show a diminution of the granulocyte-macrophage progenitor cells in individuals under treatment, compared with the control group, after a 14 days incubation period. The group of children out of treatment shows a higher number of progenitor cells after 7 days of incubation (mature progenitors), but number decreases after 14 days (immature progenitors). Therefore, we can deduce a toxic effect, direct or indirect, but probably sustained, of the chemotherapy on the granulomonocytic precursor cells.


Assuntos
Antineoplásicos/efeitos adversos , Granulócitos/citologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Monócitos/citologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Adolescente , Antineoplásicos/uso terapêutico , Criança , Pré-Escolar , Granulócitos/efeitos dos fármacos , Humanos , Lactente , Monócitos/efeitos dos fármacos , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangue , Fatores de Tempo
19.
Radiol Technol ; 51(4): 463-6, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-7355195

RESUMO

Tenure is being questioned by the public in light of competency-based education and teacher accountability. Academic freedom is essential, but some tenured faculty compromise the quality of education students receive. Renewable contracts may hold part of the answer to this issue.


Assuntos
Docentes , Tecnologia Radiológica/educação , Relações Comunidade-Instituição , Emprego , Escolas para Profissionais de Saúde , Ensino
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