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1.
Phys Rev Lett ; 113(15): 152004, 2014 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-25375706

RESUMEN

We measured the ratios of electroproduction cross sections from a proton target for three exclusive meson-baryon final states: ΛK(+), pπ(0), and nπ(+), with the CLAS detector at Jefferson Lab. Using a simple model of quark hadronization, we extract qq creation probabilities for the first time in exclusive two-body production, in which only a single qq pair is created. We observe a sizable suppression of strange quark-antiquark pairs compared to nonstrange pairs, similar to that seen in high-energy production.

2.
Methods Inf Med ; 51(1): 3-12, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22183796

RESUMEN

OBJECTIVES: Clinical data was analyzed to find an efficient way to localize the accessory pathway in patients with ventricular preexcitation. METHODS: The delta wave morphologies and ablation sites of 186 patients who underwent catheter ablation were analyzed and an algorithm ("locAP") to localize the accessory pathway was developed from the 84 data sets with a PQ interval ≤0.12s and a QRS width ≥0.12s. Fifty additional patients were included for a prospective validation. The locAP algorithm ranks 13 locations according to the likelihood that the accessory pathway is localized there. The algorithm is based on the locAP score which uses the standardized residuals of the available data sets. RESULTS: The locAP algorithm's accuracy is 0.54 for 13 locations, with a sensitivity of 0.84, a specificity of 0.97, and a positive likelihood ratio of 24.94. If the two most likely locations are regarded, the accuracy rises to 0.79, for the three most likely locations combined the accuracy is 0.82. This new algorithm performs better than Milstein's, Fitzpatrick's, and Arruda's algorithm both in the original study population as well as in a prospective study. CONCLUSIONS: The locAP algorithm is a valid and valuable tool for clinical practice in a cardiac electrophysiology laboratory. It could be shown that use of the locAP algorithm is favorable over the localizing algorithms that are in clinical use today.


Asunto(s)
Fascículo Atrioventricular Accesorio/patología , Algoritmos , Síndrome de Wolff-Parkinson-White/patología , Fascículo Atrioventricular Accesorio/diagnóstico , Adolescente , Adulto , Anciano , Ablación por Catéter/instrumentación , Distribución de Chi-Cuadrado , Niño , Electrofisiología/instrumentación , Femenino , Humanos , Laboratorios de Hospital , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Programas Informáticos , Complejos Prematuros Ventriculares/diagnóstico , Complejos Prematuros Ventriculares/patología , Síndrome de Wolff-Parkinson-White/diagnóstico , Síndrome de Wolff-Parkinson-White/cirugía , Adulto Joven
3.
Phys Rev Lett ; 105(11): 112301, 2010 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-20867566

RESUMEN

Because of their long lifetimes, the ω and ϕ mesons are the ideal candidates for the study of possible modifications of the in-medium meson-nucleon interaction through their absorption inside the nucleus. During the E01-112 experiment at the Thomas Jefferson National Accelerator Facility, the mesons were photoproduced from 2H, C, Ti, Fe, and Pb targets. This Letter reports the first measurement of the ratio of nuclear transparencies for the e+e- channel. The ratios indicate larger in-medium widths compared with what have been reported in other reaction channels. The absorption of the ω meson is stronger than that reported by the CBELSA-TAPS experiment and cannot be explained by recent theoretical models.

4.
Phys Rev Lett ; 105(22): 222501, 2010 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-21231381

RESUMEN

We have measured the 3He(e,e' pp)n reaction at an incident energy of 4.7 GeV over a wide kinematic range. We identified spectator correlated pp and pn nucleon pairs by using kinematic cuts and measured their relative and total momentum distributions. This is the first measurement of the ratio of pp to pn pairs as a function of pair total momentum p(tot). For pair relative momenta between 0.3 and 0.5 GeV/c, the ratio is very small at low p(tot) and rises to approximately 0.5 at large p(tot). This shows the dominance of tensor over central correlations at this relative momentum.

5.
Phys Rev Lett ; 105(26): 262002, 2010 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-21231647

RESUMEN

We report the first measurement of the transverse momentum dependence of double-spin asymmetries in semi-inclusive production of pions in deep-inelastic scattering off the longitudinally polarized proton. Data have been obtained using a polarized electron beam of 5.7 GeV with the CLAS detector at the Jefferson Lab (JLab). Modulations of single spin asymmetries over the azimuthal angle between lepton scattering and hadron production planes ϕ have been measured over a wide kinematic range in Bjorken x and virtual photon squared four-momentum Q2. A significant nonzero sin2ϕ single spin asymmetry was observed for the first time indicating strong spin-orbit correlations for transversely polarized quarks in the longitudinally polarized proton.

6.
Phys Rev Lett ; 103(1): 012301, 2009 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-19659138

RESUMEN

We report a measurement of the differential cross section for the gamman-->pi- p process from the CLAS detector at Jefferson Laboratory in Hall B for photon energies between 1.0 and 3.5 GeV and pion center-of-mass (c.m.) angles (thetac.m.) between 50 degrees and 115 degrees. We confirm a previous indication of a broad enhancement around a c.m. energy ([sqrt]s) of 2.1 GeV at thetac.m.=90 degrees in the scaled differential cross section s7dsigma/dt and a rapid falloff in a center-of-mass energy region of about 400 MeV following the enhancement. Our data show an angular dependence of this enhancement as the suggested scaling region is approached for thetac.m. from 70 degrees to 105 degrees.

7.
Phys Rev Lett ; 101(20): 202002, 2008 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-19113330

RESUMEN

Evidence is reported for the existence of a parity doublet of Delta resonances with total angular momentum J=3/2 from photoproduction of the ppi;{0}eta final state. The two parity partners Delta(1920)P33 and Delta(1940)D33 make significant contributions to the reaction. Cascades of resonances into Delta(1232)eta, N(1535)pi, and Na0(980) are clearly observed.

8.
Phys Rev Lett ; 100(25): 252002, 2008 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-18643655

RESUMEN

Quasifree photoproduction of eta mesons off nucleons bound in the deuteron has been measured with the CBELSA/TAPS detector for incident photon energies up to 2.5 GeV at the Bonn ELSA accelerator. The eta mesons have been detected in coincidence with recoil protons and recoil neutrons, which allows a detailed comparison of the quasifree n(gamma,eta)n and p(gamma,eta)p reactions. The excitation function for eta production off the neutron shows a pronounced bumplike structure at W=1.68 GeV (E{gamma} approximately 1 GeV), which is absent for the proton.

9.
Phys Rev Lett ; 100(19): 192302, 2008 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-18518443

RESUMEN

Information on hadron properties in the nuclear medium has been derived from the photoproduction of omega mesons on the nuclei C, Ca, Nb, and Pb using the Crystal Barrel/TAPS detector at the ELSA tagged photon facility in Bonn. The dependence of the omega-meson cross section on the nuclear mass number has been compared with three different types of models: a Glauber analysis, a Boltzmann-Uehling-Uhlenbeck analysis of the Giessen theory group, and a calculation by the Valencia theory group. In all three cases, the inelastic omega width is found to be 130-150 MeV/c(2) at normal nuclear matter density for an average 3-momentum of 1.1 GeV/c. In the rest frame of the omega meson, this inelastic omega width corresponds to a reduction of the omega lifetime by a factor approximately 30. For the first time, the momentum dependent omegaN cross section has been extracted from the experiment and is in the range of 70 mb.

10.
Rehabilitation (Stuttg) ; 45(6): 359-68, 2006 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-17123218

RESUMEN

Patients who are referred to psychosomatic inpatient rehabilitation are mostly suffering from long-term illnesses. Therefore, it is necessary to take pre- and post-treatment into account. Epidemiological questions are frequency and type of pre- and post-treatment and their relation to course and outcome of rehabilitation. Pre-treatment, recommendations for follow-up treatment, and course of treatment in 1284 patients of the department of behaviour therapy and psychosomatics of the rehabilitation centre Seehof were assessed. Before admission, 75.4 % of patients had been in psychiatric treatment, and 31.3 % had received psychotherapy. The inpatient stay was significantly longer in patients with psychiatric pre-treatment and those with a combination of psychiatric treatment and psychotherapy. These patients were more often unemployed and showing an insufficient social network. Pre-treatment was unrelated to changes in the SCL-90-R, to physician ratings of therapeutic outcome or the ability to work at the end of rehabilitation. Patients pre-treated by a general practitioner, psychiatrist or psychotherapist returned to that therapeutic setting after rehabilitation. Patients only treated by general practitioners were referred to specialist treatment. These data show the need to integrate inpatient rehabilitation in long-term pre- and post-treatment. One effect of inpatient rehabilitation is to optimize treatment. This requires good communication across different areas of health care.


Asunto(s)
Terapia Conductista , Enfermedad Crónica/rehabilitación , Trastornos Psicofisiológicos/rehabilitación , Psicoterapia , Adulto , Berlin , Enfermedad Crónica/epidemiología , Enfermedad Crónica/psicología , Comorbilidad , Evaluación de la Discapacidad , Medicina Familiar y Comunitaria , Femenino , Humanos , Tiempo de Internación , Masculino , Trastornos Mentales/epidemiología , Trastornos Mentales/psicología , Trastornos Mentales/rehabilitación , Persona de Mediana Edad , Grupo de Atención al Paciente , Trastornos Psicofisiológicos/epidemiología , Trastornos Psicofisiológicos/psicología , Derivación y Consulta , Centros de Rehabilitación , Rehabilitación Vocacional , Rol del Enfermo , Perfil de Impacto de Enfermedad
11.
Phys Rev Lett ; 94(19): 192303, 2005 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-16090166

RESUMEN

The photoproduction of omega mesons on nuclei has been investigated using the Crystal Barrel/TAPS experiment at the ELSA tagged photon facility in Bonn. The aim is to study possible in-medium modifications of the omega meson via the reaction gamma + A --> omega + X --> pi(0)gamma + X('). Results obtained for Nb are compared to a reference measurement on a LH2 target. While for recoiling, long-lived mesons (pi(0), eta, and eta;(')), which decay outside of the nucleus, a difference in the line shape for the two data samples is not observed, we find a significant enhancement towards lower masses for omega mesons produced on the Nb target. For momenta less than 500 MeV/c an in-medium omega meson mass of M(medium) = [722(+4)(-4)(stat)+35-5(syst)] MeV/c(2) has been deduced at an estimated average nuclear density of 0.6rho(0).

12.
Phys Rev Lett ; 94(1): 012003, 2005 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-15698070

RESUMEN

Single pi(0) photoproduction has been studied with the CB-ELSA experiment at Bonn using tagged photon energies between 0.3 and 3.0 GeV. The experimental setup covers a very large solid angle of approximately 98% of 4pi. Differential cross sections dsigma/dOmega have been measured. Complicated structures in the angular distributions indicate a variety of different resonances being produced in the s channel intermediate state gammap-->N(*)(Delta(*))-->ppi(0). A combined analysis including the data presented in this letter along with other data sets reveals contributions from known resonances and evidence for a new resonance N(2070)D15.

13.
Phys Rev Lett ; 94(1): 012004, 2005 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-15698071

RESUMEN

Total and differential cross sections for the reaction p(gamma,eta)p have been measured for photon energies in the range from 750 MeV to 3 GeV. The low-energy data are dominated by the S11 wave which has two poles in the energy region below 2 GeV. Eleven nucleon resonances are observed in their decay into peta. At medium energies we find evidence for a new resonance N(2070)D15 with (M,Gamma)=(2068+/-22, 295+/-40) MeV. At gamma energies above 1.5 GeV, a strong peak in the forward direction develops, signaling the exchange of vector mesons in the t channel.

14.
Z Kardiol ; 93(12): 954-63, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15599570

RESUMEN

AIMS: Previous studies have shown higher hospital mortality rates in women, especially younger women, than in men. In light of the fact that myocardial infarction therapy is rapidly developing, and since gender-specific aspects have been discussed in detail during recent years, it was our goal to re-evaluate factors influencing hospital mortality rate, especially those involving gender-specific differences, in the city of Berlin, Germany. METHODS: We prospectively collected data from 5133 patients (3330 men and 1803 women) with acute myocardial infarction who were treated in 25 hospitals in Berlin during the years 1999 to 2002. RESULTS: During hospitalization the overall mortality rate was 18.6% among women and 8.4% among men. Women were older (mean age for men 62 years; women 73 years) and less likely to be married (men 74.6%; women 36.9%) than men. Women generally took longer to arrive at the hospital after infarction than did men (median time: men 2.0 h; women 2.6 h). Women furthermore demonstrated a higher proportion of diabetes (men 22.8%; women 36.5%) and hypertension (men 58.0%; women 69.3%). Reperfusion therapy (men 68.8%; women 49.7%) and administration of beta-blockers (men 76.0%; women 66.0%) took place less often for women than for men. A multivariate analysis revealed the following factors to be independent predictors of hospital mortality: age, gender, diabetes mellitus, hypercholesterolemia, pre-existing heart failure, pre-hospital cardiopulmonary resuscitation, cardiogenic shock and pulmonary congestion on admission, admission to a hospital with >600 beds, ST-elevation in the initial ECG, reperfusion therapy, as well as beta-blocker and ACE inhibitor treatment within 48 h of hospitalization. CONCLUSION: Even after adjustment in multivariate analysis, women with acute myocardial infarction still demonstrate a higher risk for in-hospital death than men.


Asunto(s)
Mortalidad Hospitalaria , Infarto del Miocardio/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Berlin , Causas de Muerte , Servicios Médicos de Urgencia/estadística & datos numéricos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/terapia , Sistema de Registros , Análisis de Regresión , Factores de Riesgo , Factores Sexuales
15.
Parasitology ; 129 Suppl: S95-111, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15938507

RESUMEN

Tick toxicoses, of which paralysis is the most widespread and dominant form, are important elements of pathogenesis induced by ticks. Tick paralysis is the most widespread and dominant form of tick toxicoses. Non-paralytic forms of tick toxicoses do occur and evidence suggests that these forms of toxicoses are not evolutionary related. While functional significance has been suggested for tick toxins, the advantages for tick survival in general are not clear. This review considers the molecular nature of tick toxins, the possibility that tick toxins have originated more than once independently and whether these toxins could have unrecognized benign functions.


Asunto(s)
Toxicosis por Garrapatas , Garrapatas/fisiología , Toxinas Biológicas/fisiología , Secuencia de Aminoácidos , Animales , Evolución Biológica , Humanos , Datos de Secuencia Molecular , Inhibidores de Proteasas/metabolismo , Parálisis por Garrapatas/epidemiología , Parálisis por Garrapatas/etiología , Parálisis por Garrapatas/parasitología , Toxicosis por Garrapatas/epidemiología , Toxicosis por Garrapatas/etiología , Toxicosis por Garrapatas/parasitología , Garrapatas/clasificación , Toxinas Biológicas/química , Toxinas Biológicas/genética
16.
Med Vet Entomol ; 16(2): 133-8, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12109706

RESUMEN

A combined molecular and phenotypic approach was used to determine whether ear mites of the genus Otodectes (Acari: Psoroptidae) belong to a single species. The second internal transcribed spacer (ITS 2) of the rDNA of 16 isolates from 11 cats, two dogs, one arctic fox and two ferrets originating from four different continents was characterized. In addition, mites from dog, cat and arctic fox were investigated morphologically. Sequence comparisons revealed five different, but closely related genotypes which did not segregate according to host species or geographical origin. Morphologically, mites of the three host species did not differ significantly in their body or leg sizes. These investigations support the view that ear mites of the genus Otodectes from different hosts and geographical origins belong to a single species, Otodectes cynotis (Hering).


Asunto(s)
ADN Ribosómico/química , Psoroptidae/clasificación , Animales , Gatos , Perros , Conducto Auditivo Externo/parasitología , Enfermedades del Oído/parasitología , Enfermedades del Oído/veterinaria , Femenino , Hurones , Zorros , Genotipo , Interacciones Huésped-Parásitos , Masculino , Infestaciones por Ácaros/parasitología , Infestaciones por Ácaros/veterinaria , Fenotipo , Filogenia , Reacción en Cadena de la Polimerasa/veterinaria , Polimorfismo Genético , Psoroptidae/anatomía & histología , Psoroptidae/genética , Especificidad de la Especie
17.
Exp Appl Acarol ; 25(6): 505-16, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11697787

RESUMEN

In unfed adult Dermacentor marginatus and D. reticulatus ticks survival and capability to restore water balance after loss of high percentages of exchangeable body water were investigated. Furthermore, it was examined how frequently dehydrated ticks of these species were able to rehydrate by uptake of atmospheric water vapour. The critical water mass, defined as the water mass remaining in a tick at the nonambulatory state, differed between light and heavy weight groups and averaged 62.4 and 55.8%, respectively, of the total body water of fully hydrated ticks in females, and 54.4 and 51.1%, respectively, in males of D. marginatus. In D. reticulatus, the corresponding figures were 55.9 and 54.7% in females and 52.1 and 52.7% in males. All ticks survived dehydration to 50, 75 or 100% of the critical water mass, and 96.7% of the D. marginatus ticks and 95.8% of the D. reticulatus ticks compensated water losses during subsequent incubation at 95% relative humidity (r.h.) and 20 degrees C. Unfed females and males of both Dermacentor spp. were capable to balance water loss very frequently over a period of several months. When ticks were repeatedly dehydrated at 0% r.h. for 7 days and rehydrated at 95% r.h. and 20 degrees C, females and males of D. marginatus reached the 50% mortality after 22 and 29 cycles of de- and rehydration, respectively, during 211 and 285 days, respectively. In D. reticulatus, 50% of females and males survived 23 and 17 cycles, respectively, during 248 and 186 days, respectively. Rehydration weights were as high or even higher as those of ticks kept at permanent 95% r.h.


Asunto(s)
Dermacentor/fisiología , Agua , Animales , Conducta Alimentaria , Femenino , Masculino
18.
Exp Appl Acarol ; 25(6): 517-23, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11697788

RESUMEN

The present review of the literature on mites of the genus Chorioptes Gervais and Van Beneden, 1859 argues for a support of the validity of C. bovis (Hering, 1845) and C. texanus Hirst, 1924 based on biological, morphological and molecular genetic studies. However, the validity of three further species. C. crewei Lavoipierre, 1958, C. mydaus Fain, 1975 and C. panda Fain and Leclerc, 1975, is regarded as questionable because discriminations of mites, which were described as isolated cases only, were based on morphological features while transfer or cross-breeding studies were not done.


Asunto(s)
Ácaros/clasificación , Animales , Clasificación , Ácaros/anatomía & histología
19.
J Clin Microbiol ; 39(12): 4495-9, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11724868

RESUMEN

The reservoirs and the modes of transmission of the most frequent microsporidial species in humans, Enterocytozoon bieneusi, are still unknown. We have examined fecal samples of 26 humans and 350 animals from 37 species to find 18 samples containing this parasite from humans, cats, pigs, cattle, and a llama. Genotypic characterization of the internal transcribed spacer of the rRNA gene resulted in 14 different genotypes, 6 of them previously undescribed. Phylogenetic analysis revealed the lack of a transmission barrier between E. bieneusi from humans and animals (cats, pigs, and cattle). Thus, E. bieneusi appears to be a zoonotic pathogen.


Asunto(s)
Enterocytozoon/clasificación , Enterocytozoon/genética , Microsporidiosis/transmisión , Zoonosis/parasitología , Zoonosis/transmisión , Enfermedades de los Animales/parasitología , Enfermedades de los Animales/transmisión , Animales , Secuencia de Bases , Gatos , Bovinos , ADN Espaciador Ribosómico/análisis , Enterocytozoon/aislamiento & purificación , Heces/parasitología , Genes de ARNr , Genotipo , Humanos , Microsporidiosis/parasitología , Microsporidiosis/veterinaria , Datos de Secuencia Molecular , Filogenia , Análisis de Secuencia de ADN
20.
Exp Appl Acarol ; 25(4): 327-52, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11603740

RESUMEN

Scanning and transmission electron microscopical investigations revealed that Genés organ in unfed and ovipositing females of Dermacentor reticulatus is formed as a double-sac-structure consisting of an outer epithelial and an inner cuticular sac. In ovipositing ticks the latter emerges through the camerostomal aperture to the exterior. Genés organ in unfed ticks consists of a corpus, two posterior horns and a pair of undeveloped glands at each side, which differentiate in ovipositing ticks to compound, branched tubular glands with a main efferent duct for each gland opening into the lumen between the epithelial and the cuticular sac. Genés organ of egg-laying females corresponds basically in morphology and structural organization to that of unfed ticks. Compared with unfed ticks, however, in ovipositing ticks the corpus and horns are longer and broader, the glands are fully developed and the cuticular sac is evertable. The epithelial sac as the outermost part of Genés organ is continuous with the hypodermis of the basis capituli and the scutum, arises at the camerostomal aperture, forms the corpus and the two blind-ending horns, passes into the epithelium of the main excretory ducts of the glands and envelops the cuticular sac. The cuticular sac passes into the cuticle of the basis capituli and the scutum, arises at the camerostomal aperture, is folded, expands into the horn tips and consists inwards of a smooth epicuticula and outwards of a fibrous endocuticula. Muscles originating from the scutum pass caudomedially through the epithelial sac and are inserted into the cuticular sac. The entire surface of the maximally everted cuticular sac is covered with an amorphous mass. In cleaned samples, ledge-like structures appear on the lateral surface. These ledges turn into balloon-like structures which extend over the medial and dorsal surface. The entire surface including the balloon-like structures and the ledges are provided with numerous cribrate pits.


Asunto(s)
Dermacentor/anatomía & histología , Oviposición/fisiología , Animales , Dermacentor/ultraestructura , Femenino , Microscopía Electrónica de Rastreo
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