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1.
Appl Opt ; 60(13): 3609-3616, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33983291

RESUMEN

During the total solar eclipses on 11 August 1999 in Kecel (Hungary) and on 29 March 2006 in Side (Turkey), two Hungarian groups performed full-sky imaging polarimetric measurements of the eclipsed sky. They observed the spatiotemporal change of the celestial polarization pattern and detected three polarization neutral points as well as two points with maximal polarization of the sky. Parallel to these studies, the polarization pattern in front of the lunar disc, the solar corona, and the surrounding sky have also been measured. During the total solar eclipse on 21 August 2017 in the USA (Rexburg-Idaho, Madras-Oregon), three American/international groups have measured the polarization characteristics of the full sky and the solar corona. The first group observed the spatiotemporal variation of the celestial polarization pattern, and the second group detected three polarization neutral points of the sky and observed two neutral points of the solar corona. The latter were named as Minnaert and van de Hulst neutral points. The third group observed two neutral points of the lunar disc. We have reanalyzed the earlier polarization patterns of the lunar disc, solar corona, and the surrounding sky measured during the Hungarian total eclipse on 11 August 1999. In these reanalyzed polarization patterns, all four neutral points observed during the eclipse on 21 August 2017 in the USA occur: the Minnaert/van de Hulst neutral point pair above/below the eclipsed Sun, where coronal polarization is canceled by sky polarization, and the northern and southern (unnamed) neutral points of the lunar disc, where the directions of polarization of coronal light and foreground skylight are perpendicular to each other with the same polarized intensity. We name the latter two polarization neutral points after Coulson and Vorobiev.

2.
Orv Hetil ; 156(32): 1281-7, 2015 Aug 09.
Artículo en Húngaro | MEDLINE | ID: mdl-26234309

RESUMEN

Despite several therapeutic possibilities the morbidity and mortality of thromboembolic disorders remain high. Improving drug compliance - i. e. keeping up the doctor's prescriptions - may be an effective tool to reach better results. To improve patients' compliance, the risk factors of non-compliance should be recognized. Among these patients' fear of adverse effects of drugs, their lack of knowledge about their illness and medication, forgetfulness, and other social, economic factors may be the most important. Furthermore, adherence may be worsened when the patient feels that the decision has been made over his/her head. Sustained medical adherence is important because anticoagulation may be a life-long treatment. The new oral anticoagulants make the matter of compliance to be current. These new type of drugs do not need regular laboratory monitoring and, therefore, compliance cannot be strictly followed. There are several studies concerning drug compliance to anticoagulant medications. Improvement of adherence is based on regular patient education after reviewing the factors of non-compliance, which needs teamwork with important roles of doctors, pharmacists, dietetics and nurses. Careful and accurate work of the participants of primary care might be complemented by the activity of anticoagulant clinics.


Asunto(s)
Anticoagulantes/administración & dosificación , Cumplimiento de la Medicación , Grupo de Atención al Paciente , Tromboembolia/prevención & control , Anticoagulantes/efectos adversos , Miedo , Humanos , Cumplimiento de la Medicación/psicología , Cumplimiento de la Medicación/estadística & datos numéricos , Factores de Riesgo , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/prevención & control , Tromboembolia/complicaciones , Tromboembolia/tratamiento farmacológico , Tromboembolia/etiología
3.
Sci Rep ; 13(1): 10409, 2023 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-37369722

RESUMEN

The differences between the consecutive world-records of shot put and hammer throw tendentiously decrease. Therefore, nowadays it would be worth taking into account the influence of certain environmental factors on the range L, such as the latitude and release azimuth direction. Both factors exert influence on L by the centrifugal acceleration acentrigugal and Coriolis acceleration aCoriolis induced by the Earth's rotation. The aim of this work is to reveal how the world-record ranking numbers would change, if acentrigugal and aCoriolis as well as the athletes' height h were taken into account during the validation of the outdoor world records of senior female and male shot-putters and hammer-throwers. Using computer modelling, we reconstruct here the release velocities v of shots and hammers and the normalized muscle work of shot-putters achieved at the 20 best consecutive world records. We determined numerous changes of world-record ranking numbers of shot put and hammer throw due to the influence of acentrigugal, aCoriolis and h. Height h has the largest effect on the range L, acentrigugal has a medium influence, and aCoriolis possesses the least impact on L. The physically most correct way would be to consider the release velocity v of the shot/hammer (easily measurable with an ultrasound/laser Doppler gauge) as the real performance of athletes, because it is practically independent of the environmental factors, and thus is a much better ranking measure of world records than the range.


Asunto(s)
Aceleración , Atletas , Humanos , Masculino , Femenino , Rotación , Simulación por Computador , Músculos
4.
Plant Environ Interact ; 3(3): 130-139, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37284427

RESUMEN

After anthesis, the majority of mature sunflower (Helianthus annuus) inflorescences face constantly East, which direction ensures maximal light energy absorbed by the inflorescences in regions where afternoons are on average cloudier than mornings. Several theories have tried to explain the function(s) of this eastward orientation. Their common assumption is that eastward facing has certain advantages for sunflowers. In sunflower plantations, the capitulum of many plants can also face North, South, or upward. Large deviations from the conducive East direction can decrease the plant's reproductive fitness. A larger mass and number of seeds, for example, can guarantee safer seed germination and better early development of more offspring. Thus, our hypothesis was that the East facing of sunflower inflorescences ensures a larger seed number and mass compared to disoriented inflorescences. This idea was tested in a sunflower plantation, where we compared the number and mass of seeds in plants, the inflorescences of which were naturally or artificially oriented northward, eastward, southward, westward, or upward. Our study tested head diameter, seed weight, and seed number in a normal agronomic field setting being different from earlier investigations. The other difference was that we tested five head orientations and only East showed significantly increased seed weight and number. Using radiational computations, we showed that East facing ensures more absorbed light energy than other orientations, except upward. This finding can be one of the reasons for the maximal seed number and mass in East-facing sunflower capitula. Although upward-facing horizontal inflorescences absorbed maximal light energy, they had the fewest and lightest seeds probably because of the larger temperature and humidity as well as the too much sunlight, all three factors impairing the normal seed development. This study is the first that compares the seed traits of all head orientations of Helianthus annuus and proposes that the absorbed radiation could play a major role in the maximal seed number and mass of east-facing heads.

5.
Sci Rep ; 12(1): 10871, 2022 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-35927437

RESUMEN

Multiple hypotheses have been proposed for possible functions of zebra stripes. The most thoroughly experimentally supported advantage of zebra stripes is their visual unattractiveness to horseflies (tabanids) and tsetse flies. We propose here a plausible hypothesis why biting horseflies avoid host animals with striped pelages: in sunshine the temperature gradients of the skin above the slightly warmer blood vessels are difficult to distinguish from the temperature gradients induced by the hairs at the borderlines of warmer black and cooler white stripes. To test this hypothesis, we performed a field experiment with tabanids walking on a host-imitating grey test target with vessel-mimicking thin black stripes which were slightly warmer than their grey surroundings in sunshine, while under shady conditions both areas had practically the same temperature as demonstrated by thermography. We found that horseflies spend more time walking on thin black stripes than surrounding grey areas as expected by chance, but only when the substrate is sunlit. This is because the black stripes are warmer than the surrounding grey areas in the sun, but not in the shade. This is consistent with the flies' well-documented attraction to warmer temperatures and provides indirect support for the proposed hypothesis. The frequent false vessel locations at the numerous black-white borderlines, the subsequent painful bitings with unsuccessful blood-sucking attempts and the host's fly-repellent reactions enhance considerably the chance that horseflies cannot evade host responses and are swatted by them. To eliminate this risk, a good evolutionary strategy was the avoidance of striped (and spotted) host animals.


Asunto(s)
Dípteros , Equidae , Animales , Dípteros/fisiología , Equidae/fisiología , Percepción , Temperatura , Termografía
6.
R Soc Open Sci ; 9(4): 211948, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35425639

RESUMEN

In the Northern Hemisphere, south is the conventional azimuth direction of fixed-tilt monofacial solar panels, because this orientation may maximize the received light energy. How does the morning-afternoon cloudiness asymmetry affect the energy-maximizing azimuth direction of such solar panels? Prompted by this question, we calculated the total light energy received by a fixed-tilt monofacial solar panel in a whole year, using the celestial motion of the Sun and the direct and diffuse radiation measured hourly throughout the year in three North American (Boone County, Tennessee, Georgia) and European (Italy, Hungary, Sweden) regions. Here we show that, depending on the tilt angle and the local cloudiness conditions, the energy-maximizing ideal azimuth of a solar panel more or less turns eastward from south, if afternoons are cloudier than mornings in a yearly average. In certain cases, the turn of the ideal azimuth of such solar panels may be worth taking into consideration, even though the maximum energy gain is not larger than 5% for nearly vertical panels. Specifically, when solar panels are fixed on vertical walls or oblique roofs with non-ideal tilt, the deviation of the energy-maximizing azimuth from the south can be incorporated in the design of buildings.

7.
Front Plant Sci ; 13: 842560, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35371122

RESUMEN

Mature sunflower (Helianthus annuus) inflorescences, which no longer follow the Sun, face the eastern celestial hemisphere. Whether they orient toward the azimuth of local sunrise or the geographical east? It was recently shown that they absorb maximum light energy if they face almost exactly the geographical east, and afternoons are usually cloudier than mornings. However, the exact average and standard deviation (SD) of the azimuth angle of the normal vector of mature sunflower inflorescences have never been measured on numerous individuals. It is imaginable that they prefer the direction of sunrise rather than that of the geographical east. To decide between these two photobiological possibilities, we photographed mature inflorescences of 14 sunflower plantations using a drone and determined the average and SD of the azimuth angle of the normal vector of 2,800 sunflower heads. We found that the average azimuth αinflorescence = 89.5° ± 42.8° (measured clockwise from the geographical north) of inflorescences practically coincided with the geographical eastern direction (αeast = 90°) instead of the azimuth of local sunrise αsunrise = 56.14° - 57.55°. Although the SD of the orientation of individual inflorescences was large (± 42.8°), our finding experimentally corroborated the earlier theoretical prediction that the energetically ideal azimuth of sunflower inflorescences is east, if mornings are usually less cloudy than afternoons, which is typical for the domestication region of H. annuus. However, the average orientation of inflorescences of two plantations in hilly landscapes more or less differed from that of the majority of plantations in plane landscapes. The reason for this deviation may be that the illumination conditions in hilly sites more or less differed from those in plane landscapes. Furthermore, in a plantation, we observed a group of south-facing inflorescences that were in shadow for about 5 h both after sunrise and before sunset. This southern orientation can be explained by the southern maximum of total light energy absorbed by the partly shadowed inflorescences during the day, as computed by our software integrating both the diffuse skylight and the direct sunlight received by sunflower inflorescences.

8.
Sci Rep ; 10(1): 21597, 2020 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-33299003

RESUMEN

The mature inflorescence of sunflowers (Helianthus annuus) orients eastward after its anthesis (the flowering period, especially the maturing of the stamens), from which point it no longer tracks the Sun. Although several hypothetical explanations have been proposed for the ecological functions of this east facing, none have been tested. Here we propose an atmospheric-optical explanation. Using (i) astronomical data of the celestial motion of the Sun, (ii) meteorological data of diurnal cloudiness for Boone County located in the region from which domesticated sunflowers originate, (iii) time-dependent elevation angle of mature sunflower heads, and (iv) absorption spectra of the inflorescence and the back of heads, we computed the light energy absorbed separately by the inflorescence and the back between anthesis and senescence. We found that the inflorescences facing east absorb the maximum radiation, being advantageous for seed production and maturation, furthermore west facing would be more advantageous than south facing. The reason for these is that afternoons are cloudier than mornings in the cultivation areas of sunflowers. Since the photosynthesizing green back of mature heads absorbs maximal energy when the inflorescence faces west, maximizing the energy absorbed by the back cannot explain the east facing of inflorescences. The same results were obtained for central Italy and Hungary, where mornings are also less cloudy than afternoons. In contrast, in south Sweden, where mornings are cloudier than afternoons, west-facing mature inflorescences would absorb the maximum light energy. We suggest that the domesticated Helianthus annuus developed an easterly final orientation of its mature inflorescence, because it evolved in a region with cloudier afternoons.


Asunto(s)
Helianthus/fisiología , Inflorescencia/fisiología , Fotosíntesis/fisiología , Luz Solar , Orientación , Tiempo (Meteorología)
9.
Orv Hetil ; 148(7): 291-8, 2007 Feb 18.
Artículo en Húngaro | MEDLINE | ID: mdl-17344148

RESUMEN

INTRODUCTION: Self-medication is a means, besides changing one's lifestyle, of buying and taking non-prescription medicaments. This practice has several advantages. People save time and energy by not sitting for hours in the consulting room of the doctor with a simple ailment, and the doctors also have more time to deal with those requiring more serious treatment. Moreover, the expenditures of the state also decrease, as patients do not visit the doctor but buy non-prescription, i.e. non-supported, medicaments. AIMS: The authors surveyed the habits and demands of a survey population concerning non-prescription medicaments, primarily in the pharmacies of Fejér county. A marketing research programme was completed in order to establish better co-operation between patients and pharmacists, within the framework of which 1450 questionnaires were distributed from March to June in 2005, 743 of which were completed and evaluated. METHOD: The authors examined, whether there were differences within the answers given to professional questions (questions 1-25 of the questionnaire) through sex, age, qualifications and earning power. Answers were analyzed by statistical methods. Statistical analyses were carried out with the SPSS 13.0 program group. Those results were published, where significant differences were found. RESULTS: Half of the respondents take medicaments regularly, 65% of them watch advertisements about medicaments several times a day. 40% of those surveyed consult a professionally-qualified person about their decision before buying non-prescription medicaments. The population obtains much information from the brochures enclosed with medicaments, and almost 70% of them read these brochures. According to their opinions, when buying non-prescription products, pharmacists always recommend other possibilities as well, and they give details about the information concerning the application of the medicaments. CONCLUSIONS: In order for people to use non-prescription products properly, it would be definitely necessary to elaborate a successful national education strategy. The population expects information concerning medicaments to be communicated in the pharmacies in an understandable way. It should be in the pharmacy where patients learn about the medicaments they take, where the pharmacist knows what other medicines have been prescribed by a doctor, and whether patients have any illnesses whereby they should not take other products.


Asunto(s)
Atención Ambulatoria/métodos , Medicamentos sin Prescripción/administración & dosificación , Automedicación , Accidentes Domésticos , Adulto , Distribución por Edad , Anciano , Analgésicos no Narcóticos/uso terapéutico , Conservadores de la Densidad Ósea/uso terapéutico , Catárticos/uso terapéutico , Resfriado Común/tratamiento farmacológico , Servicios Comunitarios de Farmacia , Costos de los Medicamentos , Empleo , Femenino , Humanos , Hungría , Masculino , Mercadotecnía , Persona de Mediana Edad , Medicamentos sin Prescripción/efectos adversos , Permiso Parental , Derivación y Consulta , Estudiantes , Encuestas y Cuestionarios , Factores de Tiempo , Vitaminas/uso terapéutico
10.
AAPS PharmSciTech ; 7(4): 98, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17285747

RESUMEN

The physical stability of 2 types of total nutrient admixtures was studied as a function of storage time and temperature. One of them contained only structured triglycerides and the other exclusively long-chain triglycerides as lipid components. To evaluate the possible changes in the kinetic stability of the emulsions and in the surface characteristics of the droplets during storage, particle size analysis, zeta potential, and dynamic surface tension measurements were performed. To follow any chemical decomposition processes that occurred during storage, the pH of the emulsions was also monitored. The mean droplet size of emulsions prepared with lipids containing exclusively long-chain triglycerides showed a remarkable increase after 4 days of storage, in contrast with that of the mixtures containing structured lipids. A combination of size distribution, zeta potential, and dynamic surface tension measurements proved to be useful for an adequate tracking of the kinetic stability of total nutrient admixtures. Structured triglycerides not only provide advantageous metabolic effects but improve the physical stability of total parenteral nutrition admixtures.


Asunto(s)
Mezclas Complejas/química , Portadores de Fármacos/química , Estabilidad de Medicamentos , Emulsiones/química , Emulsiones Grasas Intravenosas/química , Lípidos/química , Nutrición Parenteral/métodos , Cinética , Ensayo de Materiales
11.
FEBS J ; 272(18): 4807-16, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16156799

RESUMEN

The expression of many membrane bound [NiFe] hydrogenases is regulated by their substrate molecule, hydrogen. The HupSL hydrogenase, encoded in the hupSLCDHIR operon, probably plays a role in hydrogen recycling in the phototrophic purple bacterium, Thiocapsa roseopersicina BBS. RpoN, coding for sigma factor 54, was shown to be important for expression, suggesting a regulated biosynthsis from the hup gene cluster. The response regulator gene, hupR, has been identified in the hup operon and expression of hupSL was reduced in a chromosomal hupR mutant, which indicated that HupR was implicated in the activation process. The hupT and hupUV genes were isolated, and show similarity to the histidine kinase element of the H2-driven signal transduction system and to the regulatory hydrogenases of Ralstonia eutropha and Rhodobacter capsulatus, respectively. Although the genes of the entire H2 sensing and regulation system were present, the expression of the hupSL genes was not affected by the presence or absence of H2. Using reverse transcription PCR, we could not detect any mRNA specific to the hupTUV genes in cells grown under diverse conditions. The hupT and hupUV mutant strains had the same phenotype as the wild-type strains. The hupT gene product, expressed from a plasmid, repressed HupSL synthesis as expected while introduction of actively expressed hupTUV genes together derepressed the HupSL activity in T. roseopersicina. The gene product of hupUV behaves similarly to other regulatory hydrogenases and shows H-D exchange activity.


Asunto(s)
Regulación Bacteriana de la Expresión Génica , Hidrógeno/farmacología , Hidrogenasas/genética , Thiocapsa roseopersicina/enzimología , Proteínas Bacterianas , Medición de Intercambio de Deuterio , Genes Reguladores , Histidina Quinasa , Familia de Multigenes , Operón , Proteínas Quinasas
12.
J Pharm Pharm Sci ; 8(3): 552-7, 2005 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-16401401

RESUMEN

PURPOSE: The physical stability of two types of total parenteral nutrient (TPN) admixtures was studied as a function of storage time and temperature. One of them contained only structured triglycerides and the other exclusively long-chain triglycerides as lipid components. METHODS: Droplet size of the mixtures was followed by photon correlation spectroscopy for 10 days. Zeta potential and dynamic surface tension measurements were carried out to evaluate the possible changes in the charge and interfacial surface tension of the emulsion droplets during the storage. pH values were monitored in order to follow the possible decomposition processes in the course of storage. RESULTS: Droplet size of emulsions prepared with lipids containing exclusively long-chain triglycerides showed remarkable increase after 4 days of storage in contrast with that of the mixtures containing structured lipids. CONCLUSIONS: The obtained results indicate that besides the advantageous metabolic effects of structured triglycerides, their application is recommended to improve the physical stability of TPN admixtures.


Asunto(s)
Emulsiones Grasas Intravenosas/análisis , Emulsiones Grasas Intravenosas/química , Triglicéridos/análisis , Triglicéridos/química , Estabilidad de Medicamentos , Fenómenos Fisiológicos de la Nutrición
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