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We consider a conventional α-Ω-dynamo model with meridional circulation that exhibits typical features of the solar dynamo, including a Hale-cycle period of around 20 years and a reasonable shape of the butterfly diagram. With regard to recent ideas of a tidal synchronization of the solar cycle, we complement this model by an additional time-periodic α-term that is localized in the tachocline region. It is shown that amplitudes of some decimeters per second are sufficient for this α-term to become capable of entraining the underlying dynamo. We argue that such amplitudes of α may indeed be realistic, since velocities in the range of m s-1 are reachable, e.g., for tidally excited magneto-Rossby waves. Supplementary Information: The online version contains supplementary material available at 10.1007/s11207-023-02173-y.
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We report Alfvén-wave experiments with liquid rubidium at the Dresden High Magnetic Field Laboratory. Reaching up to 63 T, the pulsed magnetic field exceeds the critical value of 54 T at which the Alfvén speed coincides with the sound speed. At this threshold, we observe a period doubling of an applied 8 kHz cw excitation, which is consistent with the theoretical expectation of a parametric resonance between magnetosonic waves and Alfvén waves. Similar mode conversions are discussed as a possible mechanism for heating the solar corona.
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The occurrence of magnetohydrodynamic quasiperiodic flows with four fundamental frequencies in differentially rotating spherical geometry is understood in terms of a sequence of bifurcations breaking the azimuthal symmetry of the flow as the applied magnetic field strength is varied. These flows originate from unstable periodic and quasiperiodic states with broken equatorial symmetry, but having fourfold azimuthal symmetry. A posterior bifurcation gives rise to twofold symmetric quasiperiodic states, with three fundamental frequencies, and a further bifurcation to a four-frequency quasiperiodic state which has lost all the spatial symmetries. This bifurcation scenario may be favored when differential rotation is increased and periodic flows with m-fold azimuthal symmetry, m being a product of several prime numbers, emerge at sufficiently large magnetic field.
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This publisher's note identifies a figure error in Appl. Opt.57, 5844 (2018)APOPAI0003-693510.1364/AO.57.005844.
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Gyroscopes IN GEneral Relativity (GINGER) is a proposed experiment with the aim of measuring in a ground laboratory the gravitoelectric and gravitomagnetic effects foreseen by general relativity through an array of ring laser gyroscopes. GINGERINO is a square ring-laser prototype that has been built to investigate the level of noise inside the Gran Sasso underground laboratory. GINGERINO has shown the advantage of the underground location. Now it provides suitable data for geophysics and seismology. Since May 2017, it has continuously acquired data. The analysis of the first 90 days shows that the duty cycle is higher than 95%, and the quantum shot noise limit is of the order of 10-10(rad/s)/Hz. It is located in a seismically active area, and it recorded part of the central Italy earthquakes. Its high sensitivity in the frequency band of fraction of hertz makes it suitable for seismology studies. The main purpose of the present analysis is to investigate the long-term response of the apparatus. Simple and fast routines to suppress the disturbances coming from the laser have been developed. The Allan deviation of the raw data reaches some 10-6 after about 106 s of integration time, while the processed data show an improvement of 1 order of magnitude. Disturbances at the daily time scale are present in the processed data, and the expected signal induced by polar motion and solid Earth tides is covered by those disturbances.
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Temporomandibular disorder (TMD) is an umbrella condition presenting several signs and symptoms including pain in the temporomandibular joint (TMJ) and masticatory muscles, articular noises, earache, headache, irregular or restricted jaw function, chewing difficulty, and limited mouth opening. Such TMD impairment may cause disorders during the chewing process. Therefore, the purpose of this systematic review was to assess chewing dysfunctions measured by sEMG, and their association with TMD. A combination and variation in the descriptors "temporomandibular joint disorders", "masticatory dysfunctions", and electromyography were used to perform the searches across databases. The databases chosen were: LILACS, PubMed, Science Direct, Scopus, and Web of Science. Additionally, grey literature was assessed using Google Scholar, ProQuest, and OpenGrey. Studies in adults that diagnosed TMD through the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD), Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) or Helkimo Protocol were selected. Furthermore, those studies should have evaluated chewing processes through surface electromyography (sEMG). Risk of bias of the included studies was assessed through the Meta-Analysis of Statistics Assessment and Review Instrument (MAStARI) tool. Eleven included studies shown significant results; however, they evaluated discrepant parameters, presented high inconsistency in the application, and had chosen different tasks to analyse the sEMG and hence, there was no consensus in the results of studies. In conclusion, strength of recommendations was very low due to a series of limitations on studies and it was not possible to made categorical statement about association between TMD and chewing dysfunctions in adults when parameters of sEMG were analysed.
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Bruxismo/fisiopatología , Dolor Facial/fisiopatología , Cefalea/fisiopatología , Masticación/fisiología , Músculos Masticadores/fisiopatología , Trastornos de la Articulación Temporomandibular/fisiopatología , Electromiografía , Dolor Facial/etiología , Cefalea/etiología , Humanos , Músculos Masticadores/diagnóstico por imagen , Rango del Movimiento Articular , Reproducibilidad de los Resultados , Trastornos de la Articulación Temporomandibular/diagnóstico por imagenRESUMEN
BACKGROUND: An important virulence mechanism of the malaria parasite Plasmodium falciparum is cytoadhesion, the binding of infected erythrocytes to endothelial cells in the second half of asexual blood stage development. Conventional methods to investigate adhesion of infected erythrocytes are mostly performed under static conditions, many are based on manual or semi-automated read-outs and are, therefore, difficult to standardize. Quartz crystal microbalances (QCM) are sensitive to nanogram-scale changes in mass and biomechanical properties and are increasingly used in biomedical research. Here, the ability of QCM is explored to measure binding of P. falciparum-infected erythrocytes to two receptors: CD36 and chondroitin sulfate A (CSA) under flow conditions. METHODS: Binding of late stage P. falciparum parasites is measured in comparison to uninfected erythrocytes to CD36- and CSA-coated quartzes by QCM observing frequency shifts. CD36-expressing cell membrane fragments and CSA polysaccharide were coated via poly-L-lysine to the quartz. The method was validated by microscopic counting of attached parasites and of erythrocytes to the coated quartzes. RESULTS: Frequency shifts indicating binding of infected erythrocytes could be observed for both receptors CD36 and CSA. The frequency shifts seen for infected and uninfected erythrocytes were strongly correlated to the microscopically counted numbers of attached cells. CONCLUSIONS: In this proof-of-concept experiment it is shown that QCM is a promising tool to measure binding kinetics and specificity of ligand-receptor interactions using viable, parasite-infected erythrocytes. The method can improve the understanding of the virulence of P. falciparum and might be used to cross-validate other methods.
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Adhesión Celular , Eritrocitos/fisiología , Eritrocitos/parasitología , Plasmodium falciparum/crecimiento & desarrollo , Tecnicas de Microbalanza del Cristal de Cuarzo/métodos , Antígenos CD36/metabolismo , Sulfatos de Condroitina/metabolismo , HumanosRESUMEN
The increasing need for sustainable agricultural practices, combined with the demand for enhanced crop productivity, has led to a growing interest in utilizing microorganisms for biocontrol of diseases and pests, as well as for growth promotion. In Brazilian agriculture, the use of plant growth-promoting rhizobacteria (PGPR) and plant growth-promoting fungi (PGPF) has become increasingly prevalent, with a corresponding rise in the number of registered microbial inoculants each year. PGPR and PGPF occupy diverse niches within the rhizosphere, playing a crucial role in soil nutrient cycling and influencing a wide range of plant physiological processes. This review examines the primary mechanisms employed by these microbial agents to promote growth, as well as the strategy of co-inoculation to enhance product efficacy. Furthermore, we provide a comprehensive analysis of the microbial inoculants currently available in Brazil, detailing the microorganisms accessible for major crops, and discuss the market's prospects for the research and development of novel products in light of current challenges faced in the coming years.
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The development of remotely controlled nanoscopic sources of heat is essential for investigating and manipulating temperature sensitive processes at the nanoscale. Here, we use single gold nanoparticles to rapidly deposit controlled amounts of heat in nanoscopic regions of defined size. This allows us to induce and control nanoscale reversible gel-fluid phase transitions in phospholipid membranes. We exploit the optical control over the phase transition to determine the velocity of the fluid phase front into the gel phase membrane and to guide the nanoparticles to specific locations. These results illustrate how single gold nanoparticles enable local thermodynamic investigation and manipulation on nanoscale (bio-) systems.
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Oro/química , Luz , Nanopartículas del Metal/química , Fosfolípidos/química , Liposomas Unilamelares/química , Transición de Fase , TemperaturaRESUMEN
Although the use of the water resources in Uzbekistan is strongly limited by their quality, it has to be noted that there is a lack of information and data within the international scientific literature with regard to the water chemical characteristics of the Amu Darya River, one of the main water resources in Central Asia. To add to such knowledge, this paper examines the spatial and temporal variation of the water quality of the Amu Darya River in order to assess its degree of degradation and the main causal factors. The functional relationships of the pollutants with respect to the flow regime are investigated. Finally an "opportune temporal window" for water withdrawal for filling the reservoirs, in relation to human consumption, will be indicated. The high salinization levels of the waters are mainly due to the presence of sulphates and chlorine. At the up-stream site salinity, although presenting elevated concentrations, does not exceed palatability levels; after the 450 km point the opportune temporal window for water withdrawal with acceptable salinity values is reduced to the period from May to September. Two main driving forces govern the temporal variation of the salinity of the Amu Darya water: a low drainage density of the area which limits the salt loads induced by the natural runoff processes, and snow and glacier melting in the upper catchment area which promotes dilution of the dissolved salts during the high-flow period. During low-flow periods salinity is strongly influenced by the return of waters used for land washing and irrigation.
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Monitoreo del Ambiente , Ríos/química , Contaminantes Químicos del Agua/análisis , Abastecimiento de Agua/análisis , Asia , Humanos , Estaciones del Año , Cloruro de Sodio/análisis , TemperaturaRESUMEN
The helical magnetorotational instability is known to work for resistive rotational flows with comparably steep negative or extremely steep positive shear. The corresponding lower and upper Liu limits of the shear are continuously connected when some axial electrical current is allowed to flow through the rotating fluid. Using a local approximation we demonstrate that the magnetohydrodynamic behavior of this dissipation-induced instability is intimately connected with the nonmodal growth and the pseudospectrum of the underlying purely hydrodynamic problem.
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Leveraging the unrivalled performance of optical clocks as key tools for geo-science, for astronomy and for fundamental physics beyond the standard model requires comparing the frequency of distant optical clocks faithfully. Here, we report on the comparison and agreement of two strontium optical clocks at an uncertainty of 5 × 10(-17) via a newly established phase-coherent frequency link connecting Paris and Braunschweig using 1,415 km of telecom fibre. The remote comparison is limited only by the instability and uncertainty of the strontium lattice clocks themselves, with negligible contributions from the optical frequency transfer. A fractional precision of 3 × 10(-17) is reached after only 1,000 s averaging time, which is already 10 times better and more than four orders of magnitude faster than any previous long-distance clock comparison. The capability of performing high resolution international clock comparisons paves the way for a redefinition of the unit of time and an all-optical dissemination of the SI-second.
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The authors have examined the morphology of Diplectanum cazauxi and Diplectanum bauchotae through the observation of 23 specimens (10 of D. cazauxi and 13 of D. bauchotae) found during May 2003 on the gills of 2 specimens of Sphyraena flavicauda Rüppell, 1838 collected at Ras Mohammed National Park, Egypt. A discriminant analysis was performed on the morphometric data of opisthaptor to determine which parameters more accurately distinguish the two species. The best discriminant parameters resulted to be the copulatory apparatus and the central bar, which determined the absence of misclassification in the model. The discriminant functions are reported for the two species.
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Enfermedades de los Peces/parasitología , Perciformes/parasitología , Trematodos/clasificación , Infecciones por Trematodos/veterinaria , Animales , Análisis Discriminante , Especificidad de la Especie , Trematodos/aislamiento & purificación , Trematodos/ultraestructura , Infecciones por Trematodos/psicologíaRESUMEN
PURPOSE: The innervation of the scleral spur region was investigated to learn whether mechano-receptors are present in this region. METHODS: Serial tangential sections and whole-mount preparations of the scleral spur region of 18 human eyes of different ages were investigated with electronmicroscopic and immunohistochemical methods. For immunohistochemistry antibodies against neurofilament-proteins, synaptophysin, substance P (SP), calcitonin gene-related peptide (CGRP), vasoactive intestinal polypeptide (VIP), neuropeptide Y (NPY), tyrosine-hydroxylase, dopamine-beta-hydroxylase, and acetylcholinesterase were used. RESULTS: Club- or bulb-shaped nerve endings with a diameter of 5 microns to 25 microns were identified in the scleral spur region throughout the whole circumference of the eyes. The terminals derive from myelinated axons with a diameter of approximately 3 microns and stain with antibodies against neurofilament-proteins and synaptophysin but do not stain for tyrosine-hydroxylase, dopamine-beta-hydroxylase, acetylcholinesterase, NPY, VIP, SP, or CGRP. Electronmicroscopically, the endings contain abundant neurofilaments, granular and agranular vesicles of different sizes, numerous mitochondria, and lysosome-like lamellated structures. The endings are incompletely ensheathed by Schwann cells. Those areas of the cell membrane of the endings that are not covered by Schwann cells are in intimate contact with the fibrillar connective tissue elements of the scleral spur. CONCLUSION: These structural features are highly characteristic for mechanoreceptive nerve endings in other tissues of the human body. The authors therefore hypothesize that the club-or bulb-shaped nerve endings in the human scleral spur are afferent mechanoreceptors that measure stress or strain in the connective tissue elements of the scleral spur. Such changes might be induced by ciliary muscle contraction and/or by changes in intraocular pressure.
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Cámara Anterior/inervación , Mecanorreceptores/ultraestructura , Terminaciones Nerviosas/ultraestructura , Esclerótica/inervación , Adulto , Anciano , Anciano de 80 o más Años , Axones/ultraestructura , Enzimas/metabolismo , Técnica del Anticuerpo Fluorescente , Humanos , Mecanorreceptores/metabolismo , Persona de Mediana Edad , Terminaciones Nerviosas/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Esclerótica/metabolismo , Esclerótica/ultraestructuraRESUMEN
PURPOSE: To study distribution and cellular localization of myocilin/trabecular meshwork-inducible glucocorticoid response protein (TIGR) in the human eye. METHODS: A peptide antibody against a portion of the myosin-like domain of myocilin/TIGR was developed. Different ocular tissues from three human donors were investigated by one- and two-dimensional gel electrophoresis and Western blot analysis. Immunohistochemistry was performed on 25 human eyes enucleated because of posterior choroidal melanoma and on 7 normal human donor eyes. RESULTS: By Western blot analysis, a band at approximately 57 kDa was visualized in cornea, trabecular meshwork, lamina cribrosa, optic nerve, retina, iris, ciliary body, and vitreous humor. By immunohistochemistry, immunoreactivity for myocilin/TIGR was observed in cells of the corneal epi- and endothelium and extracellularly in the corneal stroma and sclera. In the trabecular meshwork, cells of the uveal and corneoscleral meshwork were stained, as was the cribriform area directly adjacent to Schlemm's canal. Positive staining was seen in cells of the ciliary epithelium, ciliary muscle, lens epithelium, and in stromal and smooth muscle cells of the iris. Throughout the entire vitreous body, fine filamentous material was positively labeled. In the retina, staining was seen along the outer surface of rods and cones, in neurons of the inner and outer nuclear layer, and in the axons of optic nerve ganglion cells. Optic nerve axons were stained in the prelaminar, laminar, and postlaminar parts of the nerve. In the region of the lamina cribrosa, astrocytes in the glial columns and cribriform plates were positively labeled. CONCLUSIONS: Myocilin TIGR is expressed in almost every ocular tissue. Depending on the respective tissue, it is observed extra- or intracellularly. The presence of myocilin/TIGR in optic nerve axons and lamina cribrosa astrocytes indicates that the trabecular meshwork might not be the only target of abnormal myocilin/TIGR in GLC1A-linked open-angle glaucoma.
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Proteínas del Citoesqueleto/metabolismo , Proteínas del Ojo/metabolismo , Ojo/metabolismo , Glicoproteínas/metabolismo , Anciano , Anciano de 80 o más Años , Animales , Segmento Anterior del Ojo/metabolismo , Anticuerpos , Western Blotting , Proteínas del Citoesqueleto/inmunología , Electroforesis en Gel Bidimensional , Proteínas del Ojo/inmunología , Técnica del Anticuerpo Fluorescente Indirecta , Glicoproteínas/inmunología , Humanos , Persona de Mediana Edad , Nervio Óptico/metabolismo , Fragmentos de Péptidos/inmunología , Conejos , Retina/metabolismo , Esclerótica/metabolismo , Úvea/metabolismo , Cuerpo Vítreo/metabolismoRESUMEN
A new noninvasive technique for observing structures in the living eye has been developed: the technique is based on intravenous application of specific antibodies, labeled with fluorescein. The immunologically marked substructures of the fundus of the eye, the only transparent organ in mammals, are photographed directly using high speed film. Combined with a digital image processor to enhance low contrast contours, this technique can be used for diagnostic purposes, as shown in rabbits with experimental toxoplasmic chorioretinitis.
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Angiografía con Fluoresceína/métodos , Técnica del Anticuerpo Fluorescente , Fondo de Ojo , Animales , Anticuerpos Antiprotozoarios , Especificidad de Anticuerpos , Coriorretinitis/diagnóstico , Coriorretinitis/etiología , Fluoresceína-5-Isotiocianato , Fluoresceínas , Humanos , Procesamiento de Imagen Asistido por Computador , Inmunoglobulina G/inmunología , Fotograbar , Conejos , Tiocianatos , Toxoplasmosis Animal/complicaciones , Toxoplasmosis Animal/diagnóstico , Toxoplasmosis Ocular/complicaciones , Toxoplasmosis Ocular/diagnósticoRESUMEN
PURPOSE: To study the innervation of the presumably contractile, myofibroblast-like scleral spur cells in human and cynomolgus monkey eyes. METHODS: Serial tangential sections of the scleral spur region of the eyes of 16 human donors and 6 cynomolgus monkeys were investigated with immunocytochemical methods. Antibodies against acetylcholinesterase, synaptophysin, alpha-smooth muscle actin, calcitonin gene-related peptide (CGRP), neuropeptide Y (NPY), nitric oxide synthase (NOS), substance P (SP), tyrosine hydroxylase (TH), and vasoactive intestinal peptide (VIP) were used. In addition, sections were processed for glyoxylic acid-induced catecholamine fluorescence (CF) and for NADPH-diaphorase (NADPH-d). RESULTS: In the eyes of both species, circumferentially oriented varicose axons were observed in the scleral spur region of all quadrants. Double labeling showed that most of these scleral spur axons were in close contact with the alpha-smooth muscle actin-positive, myofibroblast-like scleral spur cells. In human eyes, the axons showed like-immunoreactivity (LI) for SP, CGRP, NPY, VIP, and NOS. In addition, numerous scleral spur axons stained for NADPH-d. Most SP-LI scleral spur axons were double-labeled for CGRP-LI, and none for VIP-LI. All NPY-LI scleral spur axons were double labeled for VIP-LI but lacked immunoreactivity to TH. Some VIP-LI axons were not labeled for NPY-LI. Nerve fibers immunoreactive (IR) for TH or positively stained for CF were not observed in association with scleral spur cells. In contrast, in cynomolgus monkey eyes, circumferentially oriented TH-IR and CF-positive varicose axons were observed frequently in the scleral spur region. In addition, SP-LI, CGRP-LI, and NPY-LI/TH-IR axons were present in the chamber angle of monkey eyes, whereas VIP-LI, VIP-LI/NPY-LI, NOS-positive, or NADPH-d-positive nerve fibers were absent. In both species, positive staining for acetylcholinesterase was seen only in the ciliary muscle, not in the scleral spur region. CONCLUSIONS: The close association of varicose axons with the myofibroblast-like scleral spur cells indicates that nervous signals modulate scleral spur cell tone. A sympathetic scleral spur cell innervation is present only in cynomolgus monkeys but seems to be absent in humans. Conversely, scleral spur axons of presumably parasympathetic origin (NOS-IR or NADPH-d-positive, VIP-LI, and VIP-LI/NPY-LI) are absent in the cynomolgus monkeys but present in humans. In both species, a cholinergic innervation of the scleral spur cells seems to be rare or absent.
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Segmento Anterior del Ojo/inervación , Sistema Nervioso Parasimpático/metabolismo , Esclerótica/inervación , Sistema Nervioso Simpático/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Animales , Segmento Anterior del Ojo/citología , Segmento Anterior del Ojo/metabolismo , Axones/metabolismo , Fibroblastos/metabolismo , Técnica del Anticuerpo Fluorescente , Humanos , Técnicas para Inmunoenzimas , Macaca fascicularis , Persona de Mediana Edad , Músculo Liso/metabolismo , Fibras Nerviosas/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Esclerótica/citología , Esclerótica/metabolismoRESUMEN
Histological data indicate the importance of tumor vascularization as a determinant of the biological behavior and the response to radiotherapy in choroidal melanoma. Duplex ultrasound and color Doppler imaging, the combination of B-mode ultrasound and pulse-waved Doppler analysis, were used to measure quantitatively neovascular blood flow in 31 patients with choroidal melanoma. Follow-up studies (20 patients) were performed to investigate the change of tumor blood flow in choroidal melanomas after radiotherapy. Blood flow was detected in 30 out of 31 melanomas (size 3.1-17.8 mm) within the tumor and at the tumor base with a mean peak systolic frequency of 1.0 kHz (range 0.3-2.7 kHz), a mean end diastolic frequency of 0.3 kHz (range 0.1-1.0 kHz), and a mean frequency of 0.7 kHz (range 0.2-1.3 kHz). Two and six months after 106Ru/106Rh beta-ray application, 19 patients showed a significant decrease in peak systolic frequency. This occurred with and in advance of the decrease in the tumor size. In one patient, a rising maximum systolic frequency after radiotherapy marked a recurrent tumor growth. Results indicate that the quantitative measurement of tumor blood flow by duplex ultrasound and color Doppler imaging may be a new diagnostic modality for monitoring the effectiveness of radiotherapy in choroidal melanoma.
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Braquiterapia , Neoplasias de la Coroides/diagnóstico por imagen , Melanoma/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Velocidad del Flujo Sanguíneo , Neoplasias de la Coroides/irrigación sanguínea , Neoplasias de la Coroides/radioterapia , Color , Femenino , Fondo de Ojo , Humanos , Masculino , Melanoma/irrigación sanguínea , Melanoma/radioterapia , Persona de Mediana Edad , Neovascularización Patológica/diagnóstico por imagen , Estudios Prospectivos , Radioisótopos , Rodio , Radioisótopos de Rutenio , UltrasonografíaRESUMEN
In a closed volume of molten sodium an intense single-vortex-like helical flow has been produced by an outside powered propeller. At a flow rate of 0.67 m(3)/s a slowly growing magnetic field eigenmode was detected. For a slightly lower flow, additional measurements showed a slow decay of this mode. The measured results correspond satisfactorily with numerical predictions for the growth rates and frequencies.
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According to recent data the incidence of second tumors in cured hereditary unilateral retinoblastoma patients is 20% within 10 years, 50% after 20 years and rises to 90% after 30 years. Nonhereditary unilateral retinoblastoma patients have not been regarded as susceptible for second nonocular tumors so far. A case is reported of such a patient having developed a second presacral retroperitoneal tumor after successful treatment of a nonhereditary unilateral retinoblastoma group V without intracranial extension or pulmonary metastases. Consequently all (hereditary and non-hereditary) retinoblastoma patients should receive at least quarterly intensive follow-up examinations after primary ophthalmologic treatment.