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1.
Phys Rev Lett ; 110(1): 012504, 2013 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-23383785

RESUMEN

The MuCap experiment at the Paul Scherrer Institute has measured the rate Λ(S) of muon capture from the singlet state of the muonic hydrogen atom to a precision of 1%. A muon beam was stopped in a time projection chamber filled with 10-bar, ultrapure hydrogen gas. Cylindrical wire chambers and a segmented scintillator barrel detected electrons from muon decay. Λ(S) is determined from the difference between the µ(-) disappearance rate in hydrogen and the free muon decay rate. The result is based on the analysis of 1.2 × 10(10) µ(-) decays, from which we extract the capture rate Λ(S) = (714.9 ± 5.4(stat) ± 5.1(syst)) s(-1) and derive the proton's pseudoscalar coupling g(P)(q(0)(2) = -0.88 m(µ)(2)) = 8.06 ± 0.55.

2.
Radiat Prot Dosimetry ; 191(2): 129-132, 2020 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-33128067

RESUMEN

The town of Zhovti Vody is a 'capital' of uranium mining and processing industry of Ukraine. The mining and processing of uranium has been carried out in this area for more than 60 y. During this period, due to increasing production activities, the town has grown significantly. As a result of production activities and also due to the human factor, the territory of the town was contaminated by radioactive rocks. In addition, out of ignorance, radioactive rocks were used in the construction of houses and roads. To normalize the radiation situation in the town, a targeted State Programme was adopted in 2003 for a period of 10 y. In 2013, the Programme was subsequently extended until 2022. In accordance with this Programme, decontamination of the urban territory, measurements of radon isotopes in houses and anti-radon reconstructions of the premises have been performed. The results of these works are described in this article.


Asunto(s)
Monitoreo de Radiación , Radón , Uranio , Humanos , Minería , Radón/análisis , Ucrania
3.
Radiat Prot Dosimetry ; 177(1-2): 198-201, 2017 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-29036372

RESUMEN

The article presents results of investigation on search and mapping of the old buried tailings with radioactive wastes on the territory of Kamianske City. For solving the problem used complex of methods. These methods are as follows: soil-gas 222Rn measurement and measurement of 222Rn flux density from the ground surface, gamma-radiation survey, prospecting drilling, gamma-ray logging and laboratory analysis of radionuclides. The leading method in this complex was the method of soil-gas 222Rn measurement. Using this method location of the tailings has been precisely defined. The tailings boundaries have been contoured in the plan. Other methods permitted to define such parameters as thickness of the wastes, their volume (~330 000 m3), radionuclide and chemical composition. It was found that radioactive residues occur at a depth from 2 to 11 m and contain in its composition 226Ra, 210Pb and 210Po in the range from 8370 to 37 270 Bq kg-1.


Asunto(s)
Residuos Radiactivos/análisis , Radón/análisis , Contaminantes Radiactivos del Suelo/análisis , Radioisótopos de Plomo/análisis , Minería , Polonio/análisis , Ucrania
4.
J Phys Condens Matter ; 28(35): 355601, 2016 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-27365361

RESUMEN

Charge transport in Na0.63CoO2 thin film deposited by a spin-coating method was investigated experimentally by time-domain terahertz spectroscopy and theoretically using Monte Carlo calculations of charge response in nano-structured materials. The dominating type of transport mechanism over the entire investigated range of temperatures (20-300 K) is a metallic-like conductivity of charges partly confined in constituting nano-sized grains. Due to the granular character of our thin film, the scattering time at low temperatures is limited by scattering on grain boundaries and the conductivity is strongly suppressed due to capture of a major fraction of charge carriers in deep traps. Nevertheless, our experimental setup and the applied model allowed us to distinguish the parameters related to the grain interior from those influenced by grain boundaries, and to conclude that the metallic type of conductivity is the intrinsic property relevant to single crystal materials.

5.
Biochim Biophys Acta ; 382(3): 286-94, 1975 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-1125236

RESUMEN

Light scattering studies on the giant squid axon were done using the technique of optical mixing spectroscopy. This experimental approach is based on the use of laser light to detect the fluctuations of membrane macromolecules which are associated with conductance fluctuations. The light scattering spectra were similar to the Lorentzian-like behavior of conductance fluctuations, possibly reflecting an underlying conformational change in the specific membrane sites responsible for the potassium ion conductance. The amplitude of the spectra measured, increased when the membrane was depolarized and decreased on hyperpolarization. The spectra were fit to the sum of two terms, a (1/f component and a simple Lorentzian term. Spectra from deteriorating axons did not show sensitivity to membrane potential changes. It is shown theoretically that fluctuations due to the voltage-dependent variable, n, of the Hodgkin-Huxley formalism are identical to the voltage fluctuations. The derived power spectrum is that of a second order system, capable of showing resonance peaking only if the voltage dependence of the potassium rate of constants is included in the analysis. The lack of resonance peaking in the observed light scattering spectra, indicates that the data are best described by a damped second order system.


Asunto(s)
Axones/ultraestructura , Membranas/ultraestructura , Animales , Decapodiformes , Látex , Luz , Matemática , Microesferas , Poliestirenos , Dispersión de Radiación , Análisis Espectral
6.
J Heart Valve Dis ; 3(6): 594-601, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8000600

RESUMEN

UNLABELLED: The long term outcome of 300 consecutive patients following percutaneous mitral commissurotomy (PMC) with the Inoue balloon was analyzed with regard to the incidence of restenosis. There were 256 females and 44 males (mean age 44.4 +/- 9.9 years, range 18-69 years), 52 had previous surgical commissurotomy, 96 were in atrial fibrillation, and 16 had a history of embolism. PCM was carried out with a success rate of 84% (no significant mitral regurgitation and mitral valve area (MVA) > 1.5 cm2). Two hundred and seventy patients were available for clinical and serial echocardiographic studies at six months, 12 months and once a year thereafter (18 patients operated on for mitral regurgitation less than six months after PMC, three patients lost to follow up, nine patients refused to return). MVA increased with PMC from 1.18 cm2 +/- 0.3 to 2.0 +/- 0.3 cm2 and then decreased to 1.8 +/- 0.3 at a mean follow up of 24.0 +/- 13.5 months (range 6-55). Echocardiographic restenosis (RS) (MVA at follow up < 1.5 cm2 with a 50% loss of the initial gain) was found in 38 patients (14%). Twenty-five (66%) of them remained in NYHA class I or II. Restenosis free survival according to the Kaplan-Mayer curve was 93%, 86%, 77% and 73% at 12,24,36 and 55 months respectively. None of the 24 clinical, hemodynamic, echocardiographic or procedural variables used on the Cox proportional hazard regression analysis identified predictors of restenosis free survival. CONCLUSIONS: The overall incidence of echocardiographic restenosis post PMC is low (12.6%) in patients followed for a mean period of two years and often occurs without worsened clinical symptoms. It may be difficult to define clinical, echocardiographic or procedural factors as significant predictors of restenosis free survival.


Asunto(s)
Cateterismo/métodos , Prótesis Valvulares Cardíacas , Estenosis de la Válvula Mitral/terapia , Adolescente , Adulto , Anciano , Cateterismo Cardíaco/métodos , Terapia Combinada , Ecocardiografía Doppler , Procedimientos Quirúrgicos Electivos , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Válvula Mitral , Estenosis de la Válvula Mitral/diagnóstico por imagen , Estenosis de la Válvula Mitral/epidemiología , Estenosis de la Válvula Mitral/fisiopatología , Análisis Multivariante , Embarazo , Complicaciones Cardiovasculares del Embarazo/terapia , Recurrencia , Tasa de Supervivencia , Factores de Tiempo , Resultado del Tratamiento
7.
Public Health Rep ; 106(4): 455-9, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1908597

RESUMEN

A national telephone survey of eye care practitioners shows that the average fee for routine eye examinations was less among optometrists than ophthalmologists. The average wait for the earliest appointment was 5 days for optometrists and 20 days for ophthalmologists. Weekend and evening appointments were also more obtainable among optometrists. The study did not determine what tests were included in the routine examination of each practitioner. Optometrists are licensed to use diagnostic drugs in all 50 States and prescribe therapeutic drugs for the treatment of ocular diseases in 25 States. Legislation that would update State laws permitting doctors of optometry to prescribe and use pharmaceutical agents for the treatment of eye diseases has been introduced in many of the remaining States. Supporters of bills permitting therapeutic pharmaceutical optometry contend that these changes would ensure the availability of quality eye care at significant savings, since optometric fees are generally lower than ophthalmological fees. In addition, it has been argued that optometrists are equitably distributed geographically and are more likely to have weekend and evening office hours, thus enabling increased patient access to eye care. When considering cost-effectiveness and accessibility, this study may provide information to those States considering changes in the scope of optometric licensure.


Asunto(s)
Honorarios Médicos/normas , Accesibilidad a los Servicios de Salud/economía , Oftalmología/economía , Optometría/economía , Citas y Horarios , Análisis Costo-Beneficio , Recolección de Datos , Prescripciones de Medicamentos , Accesibilidad a los Servicios de Salud/normas , Humanos , Licencia Médica , Medicaid/economía , Medicare/economía , Oftalmología/legislación & jurisprudencia , Oftalmología/normas , Oftalmoscopía/economía , Oftalmoscopía/normas , Optometría/legislación & jurisprudencia , Optometría/normas , Pautas de la Práctica en Medicina/economía , Estados Unidos , Selección Visual/economía , Selección Visual/normas
8.
Public Health Rep ; 96(5): 404-9, 1981.
Artículo en Inglés | MEDLINE | ID: mdl-7027299

RESUMEN

A 1979 survey of vision screening requirements in 52 Early and Periodic Screening Diagnosis and Treatment (EPSDT) programs revealed that 17 percent of the programs had no requirements, and 17 percent required only distance visual acuity testing. An additional 25 percent required distance vision and ocular muscle-fusion tests only, and the remaining programs required various combinations of three or more tests. Fewer than two-thirds of the programs with requirements had referral criteria for the tests. The ages at which initial testing was required also varied among the programs. The differences in requirements were not related to the demographic, socioeconomic, and other variables analyzed in this study. Programs with specific referral criteria, however, had a higher percentage of referrals for vision screening than those without such criteria. Because of the variability in vision screening standards and referral criteria observed among the programs, the authors conclude that national standards are needed.


Asunto(s)
Servicios de Salud del Niño/organización & administración , Tamizaje Multifásico/normas , Programas Nacionales de Salud/organización & administración , Trastornos de la Visión/prevención & control , Adolescente , Adulto , Niño , Preescolar , Humanos , Lactante , Medicaid , Estados Unidos , Trastornos de la Visión/diagnóstico , Trastornos de la Visión/terapia , Pruebas de Visión
9.
Optometry ; 72(11): 713-23, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12363259

RESUMEN

BACKGROUND: The Internet is a major conduit of health information. Consumers frequently rely on it without verifying its validity. The purpose of this study was to assess the accuracy and currency of Internet-based information on the roles and practice of optometrists, which has been found to be misleading, inaccurate, and often outdated. METHODS: Using search engines and ranking directories, 16 popular health Web sites were examined for differentiation between optometry and ophthalmology. Each site's eye care content was reviewed for syndication, definitions, provider directories, linkages to eye organizations, and provider recommendations in treatment of certain conditions. RESULTS: Many Web sites use a syndicated source for their health content and several use Merriam-Webster as their primary dictionary. A majority of sites provided poor definitions for optometry. Most Web sites were biased in recommending ophthalmologists and do not include optometrists as licensed providers in treatment of certain eye diseases. For example, Intelihealth, Aetnaushc, and Noah-Health recommend only ophthalmologists for the treatment of conjunctivitis. CONCLUSIONS: Inaccuracies and misleading information about optometry do exist and undermine the role of optometrists in delivery of eye care. When alerted, several Web sites were receptive to proposed changes. While some efforts have been undertaken to monitor Web sites, the profession must develop a concrete effort to ensure that it is correctly represented on the Internet.


Asunto(s)
Educación en Salud , Internet , Oftalmología , Optometría , Humanos
10.
Optometry ; 71(12): 781-90, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11145303

RESUMEN

BACKGROUND: Recent developments in the education and licensure of optometrists have created new opportunities for more-efficient provision of eye care. This study was conducted to determine the extent to which optometrists provided various kinds of eye care independently in managed care organizations. We compared optometric practices in health plans located in states in which the legal authority of optometrists was limited, to optometric practices in plans situated in states in which optometric licensure permitted broader prescribing authority. The volume and nature of referrals to ophthalmologists were assessed in relation to state law and organizational protocols. METHODS: A 15-item patient encounter form was developed and completed for all patients examined by the optometrists at each site during a 4-week period in 1998. Specific conditions were selected and criteria developed to help determine whether referrals to ophthalmologists were appropriate, or if they could have been managed by the optometrist These referrals were assessed by an independent panel of four optometrists. RESULTS: This study documented that optometrists provide a substantial range of eye care, and their individual scope of practice is influenced not only by legal boundaries, but also by financial and organizational factors found within managed care organizations. The pattern of referrals to ophthalmologists helped indicate the extent to which optometrists were underutilized or used appropriately in various settings. CONCLUSIONS: There is no single reliable predictor of whether optometrists will be used at the highest level of their abilities and scope of license. Although state licensure sets the overall parameters for care, optometric practice in managed care plans may be modified by internal protocols and organizational factors.


Asunto(s)
Oftalmopatías/terapia , Programas Controlados de Atención en Salud/organización & administración , Optometría/organización & administración , Derivación y Consulta/organización & administración , Anciano , Humanos , Oftalmología/organización & administración , Optometría/métodos , Estudios Retrospectivos , Estados Unidos
11.
Manag Care Interface ; 14(3): 55-62, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11301954

RESUMEN

The integrated relationship and roles in managed care of ophthalmologists, optometrists, and opticians have changed profoundly in recent years. The change is in part the result of the advancement of optometric education and license in the diagnosis and treatment of ocular disease. The change has also evolved because of the influence of managed care and its objective to reduce costs while elevating quality of care. The authors explain that vertical integration of all ophthalmic services, ranging from eye examination to eyeglass dispensing to ocular surgery, can help MCOs maximize quality and minimize costs.


Asunto(s)
Cobertura del Seguro , Programas Controlados de Atención en Salud/organización & administración , Oftalmología/organización & administración , Optometría/organización & administración , Oftalmopatías/diagnóstico , Oftalmopatías/terapia , Anteojos/economía , Planes de Asistencia Médica para Empleados/organización & administración , Humanos , Relaciones Interprofesionales , Gestión de la Calidad Total , Estados Unidos
12.
Manag Care Interface ; 12(9): 52-8, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10621102

RESUMEN

This study was conducted to determine how managed care plans use optometrists to provide vision and eye care. The study documents the variety of optometric practice patterns found within six health plans in several states, each having different organizational characteristics, professional staffing patterns, and payment arrangements, and each regulated by dissimilar state licensure laws. A 15-item patient encounter form was developed and completed for all patients examined by the optometrists at each site during a four-week period. The instrument included information on patient demographics, medical/ocular history, reason for the visit, procedures performed, diagnosis, therapy provided, ocular medications prescribed, prognosis, disposition, referrals, and duration of the visit. A variety of patterns were found, some of which did not necessarily closely follow the legal boundaries of optometric care. This study documented that optometrists provide a substantial volume and range of vision care, and their scope of practice is influenced by legal, financial, and organizational factors. In some plans, optometrists' skills were underutilized relative to their legal authority in certain situations; in others, creative, cooperative arrangements extended the benefits of optometry beyond the existent practice laws. Licensure is certainly a major influence on the scope of practice of health providers. This study revealed, however, that licensure alone does not appear to be the only determinant of use, delegation, and division of labor among health professionals, and that organizational factors seem to play a very significant role.


Asunto(s)
Programas Controlados de Atención en Salud/organización & administración , Optometría/organización & administración , Grupos Diagnósticos Relacionados/estadística & datos numéricos , Prescripciones de Medicamentos/estadística & datos numéricos , Investigación sobre Servicios de Salud , Pautas de la Práctica en Medicina/estadística & datos numéricos , Derivación y Consulta/estadística & datos numéricos , Estados Unidos
13.
14.
Med Pr ; 28(5): 441-7, 1977.
Artículo en Polaco | MEDLINE | ID: mdl-607093

RESUMEN

Yearly measurements of external noise (Noise--Pollution--Level) in the shipyard in Stettin, indicated noise levels above 85 dBA, expressed in LqM. On the ground of documentation of periodic medical examinations of the staff, one compared the rate of occurrence of disturbances in health state, such as: hearing impairment, gastric and duodenal peptic ulcer, hypertension and psychic disturbances in two groups of employees: "A"--exposed during work to noise 85 dBA and "B"--employed at the area of LqM smaller by 20 dBA. Statistically significant differences in the rates of occurrence of disturbances in the health state were found, to the disadvantage of those exposed to noise effect. In these groups also the rate of sickness absenteeism was disadvantageous: in the last 14 years its average values for the shipyard surpassed the average rate for Stettin district and the whole country.


Asunto(s)
Trastornos de la Audición/etiología , Ruido/efectos adversos , Enfermedades Profesionales/etiología , Navíos , Humanos , Hipertensión/etiología , Úlcera Péptica/etiología
15.
Med Pr ; 32(6): 417-21, 1981.
Artículo en Polaco | MEDLINE | ID: mdl-7043158

RESUMEN

The literature data indicating nonspecific pathologic symptoms of the circulatory system in those occupationally exposed to caprolactam and diphenyl inspired the authors to evaluate the circulatory system in a group of 495 workers of a Chemical Plant producing polyamide fibres. The anamnestic data, family inquiry and subjective changes indicate that any hints of the significant effects of the technological process on circulatory diseases in this professional group are unwarranted. The percentage values of the latent circulatory failure (1-2% of subjects), coronary insufficiency (6.6% of subjects), arterial hypertension (5.7% of subjects) did not show any significant differences, as compared to the control group and normal Polish population. The obtained results of ECG test evaluated according to the Minnesota-Code criterion did not significantly differ from 100 controls composed of those in whom no changes in the circulatory system were found, whereas clear differences were found related to 50 persons with documented heart ischemia.


Asunto(s)
Azepinas/efectos adversos , Compuestos de Bifenilo/efectos adversos , Caprolactama/efectos adversos , Sistema Cardiovascular/efectos de los fármacos , Industria Química , Poliaminas/efectos adversos , Adulto , Enfermedades Cardiovasculares/inducido químicamente , Enfermedades Cardiovasculares/diagnóstico , Diagnóstico por Computador , Electrocardiografía , Femenino , Humanos , Masculino , Enfermedades Profesionales/inducido químicamente , Enfermedades Profesionales/diagnóstico , Polonia
16.
J Pharm Belg ; 48(1): 33-6, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8483098

RESUMEN

Pharmacological properties of a series of alpha, omega-diamino-omega-phosphonocarboxylic acids and alpha, omega-diamino-alpha, omega-bis(phosphonic acids) on different excitatory amino acids mediated responses have been tested in CA1 rat hippocampal neurones, using intracellular recordings and current and voltage clamp techniques. In contrast with known antagonists as D(-)2-amino-5-phosphonopentanoic acid (AP-5) and 2-amino-4-oxo-5-phosphonopentanoic acid, which completely abolished the NMDA-response, no antagonistic activity was found. We conclude that the introduction of an omega-amino function abolishes the NMDA-antagonistic activity of alpha-amino-omega-phosphonocarboxylic acids.


Asunto(s)
Organofosfonatos/farmacología , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Animales , Hipocampo/metabolismo , Técnicas In Vitro , Ligandos , Masculino , Ratas , Ratas Wistar , Receptores de Glutamato/efectos de los fármacos
17.
J Pharm Belg ; 48(1): 37-42, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8483099

RESUMEN

Pharmacological properties of 2-amino-4-oxo-5-phosphonopentanoic acid (AOPA) on excitatory amino acids mediated responses have been tested in CA1 rat hippocampal neurones, using intracellular recordings and current and voltage clamp techniques. These properties were compared with those of the well-known NMDA antagonist, D(-)2-amino-5-phosphonopentanoic acid (AP-5). AOPA completely abolished the response to NMDA but had no effects on the responses to AMPA, quisqualate and kainate. In voltage clamp experiments AOPA antagonized NMDA-induced currents and produced a parallel shift of the NMDA concentration-response curve. Schild analysis gave a Kd value of 26 microM. AP-5 also produced a similar shift in this curve with a Kd of 6.9 mu.


Asunto(s)
Aminoácidos/farmacología , Ácidos Levulínicos/farmacología , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Animales , Hipocampo/efectos de los fármacos , Técnicas In Vitro , Ligandos , Masculino , N-Metilaspartato/antagonistas & inhibidores , Ratas , Ratas Wistar , Receptores de Glutamato/efectos de los fármacos , Relación Estructura-Actividad
18.
Wiad Parazytol ; 45(4): 507-17, 1999.
Artículo en Polaco | MEDLINE | ID: mdl-16888993

RESUMEN

Among Polish ticks species the most common Ixodes ricinus has the biggest medical importance. Within the last few years, the incidence of disease transmitted by ticks has rapidly increased. We have made a thorough analysis of the quantative and rate per cent of occurrence of various stages Ixodes ricinus in the forest areas of some places in Szczecin province and in the parks of Szczecin, that are known as highly recreative and frequently visted by many people. A total of 426 (68% numphs) specimens collected there show that ticks frequently occupy habitats closely associated with man.


Asunto(s)
Monitoreo del Ambiente/estadística & datos numéricos , Ixodes , Instalaciones Públicas/estadística & datos numéricos , Árboles/parasitología , Animales , Vectores Arácnidos , Femenino , Humanos , Larva , Masculino , Ninfa , Polonia , Densidad de Población , Estaciones del Año
19.
J Appl Genet ; 51(4): 469-76, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21063064

RESUMEN

Mitochondrial genomes are frequently used to infer phylogenetic relationships. Some taxa are, however, poorly represented. To facilitate better understanding of the potential of mitochondrial genome data in freshwater mussels, we present here, for the first time, the mitochondrial sequences of 4 complete F-type mitochondrial genomes from the European freshwater bivalve Unio pictorum (Unionidae). These genomes are very compact (15,761 bp) but have a typical gene complement for bilaterian mitochondrial genomes and a very similar organization to other unionid genomes available in databases. Very low nucleotide diversity within the species suggests a small effective population size of Polish U. pictorum, a phenomenon of potential importance for environmental management policies.


Asunto(s)
Genoma Mitocondrial/genética , Patrón de Herencia/genética , Unio/genética , Animales , Composición de Base/genética , Secuencia de Bases , Mapeo Cromosómico , ADN Intergénico/genética , Femenino , Haplotipos/genética , Masculino , Datos de Secuencia Molecular , Análisis de Secuencia de ADN
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