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1.
Phys Rev Lett ; 124(8): 081803, 2020 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-32167372

RESUMEN

We present the result of an experiment to measure the electric dipole moment (EDM) of the neutron at the Paul Scherrer Institute using Ramsey's method of separated oscillating magnetic fields with ultracold neutrons. Our measurement stands in the long history of EDM experiments probing physics violating time-reversal invariance. The salient features of this experiment were the use of a ^{199}Hg comagnetometer and an array of optically pumped cesium vapor magnetometers to cancel and correct for magnetic-field changes. The statistical analysis was performed on blinded datasets by two separate groups, while the estimation of systematic effects profited from an unprecedented knowledge of the magnetic field. The measured value of the neutron EDM is d_{n}=(0.0±1.1_{stat}±0.2_{sys})×10^{-26} e.cm.

2.
Opt Express ; 23(17): 22108-15, 2015 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-26368184

RESUMEN

We present a magnetometer based on optically pumped Cs atoms that measures the magnitude and direction of a 1 µT magnetic field. Multiple circularly polarized laser beams were used to probe the free spin precession of the Cs atoms. The design was optimized for long-time stability and achieves a scalar resolution better than 300 fT for integration times ranging from 80 ms to 1000 s. The best scalar resolution of less than 80 fT was reached with integration times of 1.6 to 6 s. We were able to measure the magnetic field direction with a resolution better than 10 µrad for integration times from 10 s up to 2000 s.

3.
Phys Rev Lett ; 115(16): 162502, 2015 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-26550870

RESUMEN

We describe a spin-echo method for ultracold neutrons (UCNs) confined in a precession chamber and exposed to a |B0|=1 µT magnetic field. We have demonstrated that the analysis of UCN spin-echo resonance signals in combination with knowledge of the ambient magnetic field provides an excellent method by which to reconstruct the energy spectrum of a confined ensemble of neutrons. The method takes advantage of the relative dephasing of spins arising from a gravitationally induced striation of stored UCNs of different energies, and also permits an improved determination of the vertical magnetic-field gradient with an exceptional accuracy of 1.1 pT/cm. This novel combination of a well-known nuclear resonance method and gravitationally induced vertical striation is unique in the realm of nuclear and particle physics and should prove to be invaluable for the assessment of systematic effects in precision experiments such as searches for an electric dipole moment of the neutron or the measurement of the neutron lifetime.


Asunto(s)
Gravitación , Modelos Teóricos , Neutrones , Frío , Cinética
4.
Stroke ; 32(12): 2945-6, 2001 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-11740001

RESUMEN

BACKGROUND: Intracranial venous congestion is often caused by local venous thrombosis or brain arteriovenous fistulas. Hemodialysis shunts are known to cause venous enlargement in the arm or chest but have not been related to intracranial vascular pathology. Case Description- A 59-year-old woman who presented with increasing headache, gait instability, and memory loss was a renal transplant recipient who still carried a left upper arm shunt. Cranial CT scan showed enlarged veins in the posterior fossa with incipient hydrocephalus. Extracranial duplex sonography revealed reversed flow in the left internal jugular vein, which normalized on cuff inflation around the shunt-carrying arm. The reversed flow, intracranial venous congestion, and neurological status improved after surgical shunt ligation. CONCLUSIONS: To our knowledge, this is the first case description of an intracranial venous outflow obstruction caused by a peripheral arteriovenous shunt.


Asunto(s)
Derivación Arteriovenosa Quirúrgica/efectos adversos , Trastornos Cerebrovasculares/diagnóstico , Trastornos Cerebrovasculares/etiología , Trombosis Intracraneal/diagnóstico , Trombosis Intracraneal/etiología , Venas Braquiocefálicas/diagnóstico por imagen , Venas Braquiocefálicas/patología , Angiografía Cerebral , Venas Cerebrales/diagnóstico por imagen , Venas Cerebrales/patología , Venas Cerebrales/fisiopatología , Trastornos Cerebrovasculares/patología , Femenino , Cefalea/etiología , Humanos , Hidrocefalia/etiología , Venas Yugulares/diagnóstico por imagen , Venas Yugulares/fisiopatología , Persona de Mediana Edad , Politetrafluoroetileno/efectos adversos , Tomografía Computarizada por Rayos X , Ultrasonografía
5.
Pediatrics ; 89(3): 407-10, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1741212

RESUMEN

Cesium 137 activity was measured after the Chernobyl incident in a whole-body radiation counter (4-pi-scintillation counter) in 85 premature and mature newborns (group 1), 174 infants and young children up to 2 11/12 years (group 2), and 48 children between 3 and 8 years (group 3) from Bonn (Germany) and surroundings. In 1987 the mean level of radioactivity in group 2, at 3.7 Bq/kg body weight corresponding to a mean radiation exposure of 11 muSv/y, was lower than that of group 1 (5.8 Bq/kg, 17 muSv/y) and 3 (9.4 Bq/kg, 28 muSv/y). Up to 1990 the values of all groups revealed a continuous decrease. The latest measurements showed mean values of 0.5 Bq/kg (1.5 muSv/y) in group 1, 0.6 Bq/kg (1.8 muSv/y) in group 2, and 0.8 Bq/kg (2.4 muSv/y) in group 3. A comparison with present cesium 137 values and determinations of the end of the 1950s and beginning of 1960s, both in adults, showed good agreement. The effective dose-equivalent rates amounted to less than 1% of that from natural radiation exposure. These levels should present no teratogenic risks to the population studied and, while there are theoretical mutagenic risks, the dose is so low that no increase in measurable mutagenic effects should be observed.


Asunto(s)
Accidentes , Radioisótopos de Cesio/análisis , Reactores Nucleares , Recuento Corporal Total , Factores de Edad , Niño , Preescolar , Estudios Transversales , Alemania , Humanos , Lactante , Recién Nacido , Recien Nacido Prematuro , Estudios Prospectivos , Ucrania
6.
Bone Marrow Transplant ; 28(8): 787-9, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11781632

RESUMEN

Treatment and prognosis have not been well characterized in germ cell tumors (GCT) with a malignant nongerm cell component. Patients with a mediastinal tumor, neural or rhabdomyosarcomatous differentiation and distant metastases have the poorest prognosis. We report a rare case of mixed GCT composed of seminoma, teratoma and rhabdomyosarcoma with the rhabdomyosarcomatous component metastasized into the liver and bone marrow (BM) causing hypercalcemia. The patient was treated with differentiation-tailored chemotherapy (CHT) including a disease-adapted high-dose (HD) CHT regimen with purified autologous PBSCT (APBSCT) and pamidronate. To date, remission has lasted for 4 years. Tumor-adapted CHT including HD-CHT with APBSCT can induce long term remissions in high-risk patients with transformed GCT. A review of the literature is given.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Trasplante de Células Madre Hematopoyéticas , Neoplasias Primarias Múltiples/tratamiento farmacológico , Rabdomiosarcoma/tratamiento farmacológico , Seminoma/tratamiento farmacológico , Teratoma/tratamiento farmacológico , Neoplasias Testiculares/tratamiento farmacológico , Médula Ósea/patología , Carboplatino/administración & dosificación , Diferenciación Celular , Cisplatino/administración & dosificación , Terapia Combinada , Difosfonatos/uso terapéutico , Epirrubicina/administración & dosificación , Etopósido/administración & dosificación , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/terapia , Vértebras Lumbares , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Neoplasias Primarias Múltiples/cirugía , Neoplasias Primarias Múltiples/terapia , Orquiectomía , Pamidronato , Inducción de Remisión , Rabdomiosarcoma/patología , Rabdomiosarcoma/secundario , Rabdomiosarcoma/cirugía , Rabdomiosarcoma/terapia , Convulsiones/etiología , Seminoma/cirugía , Seminoma/terapia , Neoplasias de la Columna Vertebral/tratamiento farmacológico , Neoplasias de la Columna Vertebral/secundario , Neoplasias de la Columna Vertebral/terapia , Teratoma/cirugía , Teratoma/terapia , Neoplasias Testiculares/cirugía , Neoplasias Testiculares/terapia , Trasplante Autólogo
7.
Rofo ; 154(4): 349-53, 1991 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-1850147

RESUMEN

Tubal patency was studied in 17 sterile women by means of colour-coded duplex sonography (CCDS) with local injection of an ultrasonic contrast medium. The results were compared with a conventional hysterosalpingogram. CCDS demonstrated all the soft tissues and their mobility. The ultrasonic contrast medium was SH U 454 (Schering). The colour signals generated by the air bubbles makes it possible to demonstrate tubal patency on both sides. The combination of an ultrasonic contrast medium and CCDS provides a simple, rapid, accurate and safe method for demonstrating tubal patency. Tubal patency can be demonstrated in the presence of anatomical complications and requires only a small amount of contrast medium.


Asunto(s)
Pruebas de Obstrucción de las Trompas Uterinas/métodos , Trompas Uterinas/diagnóstico por imagen , Adulto , Color , Medios de Contraste/administración & dosificación , Pruebas de Obstrucción de las Trompas Uterinas/instrumentación , Femenino , Humanos , Infertilidad Femenina/diagnóstico por imagen , Polisacáridos , Ultrasonografía
8.
Rofo ; 154(3): 242-5, 1991 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-1849290

RESUMEN

The diagnostic use of microbubble consisting transpulmonary ultrasound contrast media in combination with color-coded duplex sonography (CCDS) has not been evaluated. Perfusion of the orthotopic kidney was therefore examined in an animal experiment with CCDS and transpulmonary echocontrast agent. The contrast agent consists of tiny stabilized air bubbles which survive the lung passage after peripheral venous injection and cause echo-enhancement of the arterial blood. The combination of CCDS and this contrast agent permits demonstration of the renal perfusion including the peripheral parenchyma. Even small experimental perfusion defects can be identified by this method. The use of this contrast agent in combination with CCDS might contribute significantly to the diagnostic potential of ultrasound.


Asunto(s)
Medios de Contraste , Riñón/irrigación sanguínea , Polisacáridos , Animales , Medios de Contraste/administración & dosificación , Perros , Inyecciones Intravenosas , Riñón/diagnóstico por imagen , Polisacáridos/administración & dosificación , Suspensiones , Ultrasonografía
9.
Eur J Med Res ; 5(1): 26-31, 2000 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-10657286

RESUMEN

OBJECTIVES: Randomized trials in North America (NASCET, ACAS) and Europe (ECST) have shown a beneficial effect of endarterectomy for patients with high grade carotid artery stenosis. The results of the NASCET and the ECST further suggest that the effect of endarterectomy differed by degree of stenosis, supporting the importance of stenosis measurement as a factor in the decision process regarding surgery. We investigated the interrater agreement for carotid artery stenosis measurements and treatment decision in a post hoc study on patients undergoing carotid surgery. METHODS: In a one-year series, 45 consecutive patients underwent preoperative conventional cerebral angiography followed by endarterectomy. Using a magnifying eyepiece and applying the two different measurement criteria of the randomized trials, angiograms were re-evaluated post hoc by three masked raters. Intra-class correlation coefficients (ICCs) with one-sided 95% confidence intervals (CIs) were calculated for the estimation of interrater agreement for degree of stenosis. Conger s kappa (k) statistics were used for the estimation of interrater agreement for a dichotomized stenosis evaluation, i.e. therapeutic decision on surgery (cut-off point for symptomatic stenosis: 70%, cut-off point for asymptomatic stenosis: 60%). RESULTS: ICCs were.74 (CI.63) for NASCET/ACAS criteria and.72 (CI. 59) for ECST criteria. k values were.55 (CI.42) for NASCET/ACAS criteria and.57 (CI.44) for ECST criteria. Disagreement for a therapeutic decision was seen in 6 of 23 symptomatic patients by NASCET criteria, in 2 of 23 symptomatic patients by ECST and in 4 of 22 asymptomatic patients by ACAS criteria. CONCLUSIONS: Overall, the interrater agreement for stenosis measurements was good. Agreement for therapeutic decisions on carotid surgery, however, was less strong. These findings suggest that accurate stenosis measurement may not suffice for reliable treatment decisions in patients with high grade carotid artery stenosis.


Asunto(s)
Estenosis Carotídea/diagnóstico , Anciano , Arterias Carótidas/diagnóstico por imagen , Estenosis Carotídea/cirugía , Endarterectomía Carotidea , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radiografía
12.
Practitioner ; 225(1351): 65-6, 69-70, 72-3, 1981 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7220463
13.
Spec Libr ; 80(4): 269-74, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-10295756

RESUMEN

The Joint Commission on Accreditation of Healthcare Organizations (JCAHO) currently requires healthcare institutions use specific, criteria-based evaluations to measure employee performance. These evaluations must be closely linked to each employee's position description. This paper discusses the revision of the library manager's position description and correlating criteria-based performance evaluation to more closely meet JCAHO requirements. The paper uses a case study featuring Chelsea Community Hospital Medical Library, Chelsea, Michigan.


Asunto(s)
Evaluación del Rendimiento de Empleados/métodos , Bibliotecas de Hospitales/organización & administración , Control de Formularios y Registros , Hospitales con 100 a 299 Camas , Joint Commission on Accreditation of Healthcare Organizations , Michigan , Administración de Personal
14.
Br J Med Psychol ; 56 (Pt 3): 245-54, 1983 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6626480

RESUMEN

Two repertory grids were administered at four-weekly intervals to members of three psychotherapy groups and one waiting-list control group. Individualized and general predictions of possible therapeutic change were made. More individualized than general predictions were confirmed, adding further support to the use of client-centred outcome measures. The outcome data indicated significant improvement in each therapy group. Process results were consonant with Yalom's (1970) curative factors of universality, modelling and family re-enactment and Malan's (1979) resolution of triangle of person. Finally, a model for further evaluation of group psychotherapy is outlined developing personal construct methodology within a group setting.


Asunto(s)
Evaluación de Procesos y Resultados en Atención de Salud , Terapia Psicoanalítica/métodos , Psicoterapia de Grupo/métodos , Adulto , Ansiedad/terapia , Femenino , Humanos , Identificación Psicológica , Masculino , Padres , Autoimagen , Transferencia Psicológica
15.
Health Manpow Manage ; 21(4): 32-6, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-10156834

RESUMEN

Outlines four interconnecting factors which are essential to motivating staff: an understanding of the "psychology of excellence in teams"; establishing cross-functional quality improvement teams; understanding and reviewing processes of care and service; and the use of data display.


Asunto(s)
Actitud del Personal de Salud , Participación en las Decisiones/organización & administración , Motivación , Evaluación de Procesos, Atención de Salud , Gestión de la Calidad Total/organización & administración , Recursos Audiovisuales , Humanos , Modelos Organizacionales , Psicología Industrial , Proyectos de Investigación , Reino Unido
16.
J R Coll Gen Pract ; 29(203): 337-40, 1979 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-522037

RESUMEN

Thirty general practitioner consultations with patients with psychological problems referred to a clinical psychologist for behaviour therapy, were examined. Treatment was carried out wholly within the practice. Consultations for advice and psychotropic drug prescriptions were compared during one year, both before and after treatment, and were found to be reduced by over 50 per cent following treatment. Contact with clinical psychology services, therefore, considerably reduced the demand made by these patients for general practitioner time.


Asunto(s)
Terapia Conductista , Medicina Familiar y Comunitaria , Trastornos Neuróticos/terapia , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trastornos Neuróticos/tratamiento farmacológico , Relaciones Médico-Paciente , Psicotrópicos/uso terapéutico , Derivación y Consulta
17.
Br J Med Psychol ; 56 ( Pt 4): 323-7, 1983 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-6661402

RESUMEN

Changes in verbal affective expression within sessions of two psychotherapy groups run along group-analytic lines were measured using the Process Affective Scoring System developed by Gibbard & Hartman (1973). Tape recordings of group sessions were rated by trained undergraduate students for presence or absence of verbal affect. Relationships between these changes and changes in personal construing were sought. Expression of hostility and affection were found to be good predictors of a successful outcome of therapy. Factors which might account for the unexplained variance of changes in outcome variables are put forward.


Asunto(s)
Afecto , Terapia Psicoanalítica/métodos , Psicoterapia de Grupo/métodos , Conducta Verbal , Trastornos de Ansiedad/psicología , Trastornos de Ansiedad/terapia , Humanos , Relaciones Interpersonales , Autoimagen
18.
Klin Padiatr ; 202(6): 422-6, 1990.
Artículo en Alemán | MEDLINE | ID: mdl-2266709

RESUMEN

The Fanconi-Bickel syndrome is characterized by tubular dysfunction, impaired metabolism of glucose and galactose and glycogenosis. Up to now the data of nineteen patients have been reported. In the following case firstly an abnormal body composition is described measuring the concentration of Potassium-40 with a Whole Body Radiation Counter. Before therapy an increased value of total body cell mass but no value of total body fat is measured. After therapy body weight increased while cell mass decreased and a value of fat had been observed. Concerning renal parameters a 60 fold elevation of the beta 2-microglobulin-clearance is noted.


Asunto(s)
Síndrome de Fanconi/diagnóstico , Constitución Corporal , Terapia Combinada , Síndrome de Fanconi/metabolismo , Síndrome de Fanconi/terapia , Galactosa/metabolismo , Glucosa/metabolismo , Humanos , Lactante , Masculino , Microglobulina beta-2/orina
19.
Klin Padiatr ; 205(6): 416-20, 1993.
Artículo en Alemán | MEDLINE | ID: mdl-8309204

RESUMEN

Vitamin D-deficiency has been observed among immigrant children with rickets and osteomalacia in Western Europe. So vitamin D-status in 34 children and juveniles (17 girls, 17 boys) of African and Asian diplomats staying in West Germany only for a certain time is examined. During summer 1989 plasma levels of alkaline phosphatase, calcium, phosphate, 25-hydroxy-cholecalciferol and 1,25-dihydroxycholecalciferol is measured. According to their native country the subjects are divided into three groups: I North Africa (n = 7), II Central Africa (n = 18), III Asia (n = 9). No clinical signs of rickets or osteomalacia are detected. All plasma levels of calcium and phosphate are in the normal range so as most of the values of the alkaline phosphatase. In Group I 85.7% (n = 6), group II 77.8% (n = 14) and group III 44.4% (n = 4) have decreased values of 25-OHD whereas most strikingly elevated amounts of 1,25-OH2D are measured in 57.1% (n = 4) of the subjects in group I, 66.7% (n = 12) in group II and 11.1% (n = 1) in group III. Normal values for both 25-OHD and 1,25-OH2D are rare: one case (11.1%) in group I, no case in group II, four cases (44.4%) in group III. The influence of the time staying in West Germany on vitamin D-status, a possible dietary lack due to inadequate nutrition, the role of skin pigmentation and a potential genetic abnormality of vitamin D-metabolism is discussed to explain the results.


Asunto(s)
Emigración e Inmigración , Etnicidad , Deficiencia de Vitamina D/epidemiología , Adolescente , África/etnología , Fosfatasa Alcalina/sangre , Asia/etnología , Calcio/sangre , Niño , Preescolar , Estudios Transversales , Femenino , Alemania , Humanos , Incidencia , Lactante , Masculino , Fosfatos/sangre , Valores de Referencia , Vitamina D/sangre , Deficiencia de Vitamina D/enzimología , Deficiencia de Vitamina D/etiología
20.
MMW Munch Med Wochenschr ; 118(31): 961-6, 1976 Jul 30.
Artículo en Alemán | MEDLINE | ID: mdl-822284

RESUMEN

Evaluation of Success Figures and Incidence Data: The survival rates of patients with esophageal, bronchail and mammary carcinoma were determined at fixed intervals as specific mean values, including the dependence of the standard deviation on the size of the treatment collectives (n = 50, 100, 1000). In addition to the statistical margin of error, the percentage frequency of bronchial and mammary carcinomas and also of leukemia in childhood was calculated in numerical and age groups. The application is demonstrated with examples.


Asunto(s)
Neoplasias/mortalidad , Adolescente , Adulto , Factores de Edad , Anciano , Neoplasias de la Mama/mortalidad , Neoplasias de los Bronquios/mortalidad , Niño , Preescolar , Neoplasias Esofágicas/mortalidad , Femenino , Alemania Occidental , Humanos , Leucemia/mortalidad , Masculino , Persona de Mediana Edad , Pronóstico , Estadística como Asunto
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