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1.
Lett Appl Microbiol ; 63(2): 131-8, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27261362

RESUMEN

UNLABELLED: We isolated, identified and characterized yeast strains from grapes, and their fermented musts, sampled in the small island of Linosa, where there are no wineries and therefore the possibility of territory contamination by industrial strains is minimal. By traditional culture-dependent methods, we isolated 3805 colonies, distinguished by molecular methods in 17 different species. Five hundred and forty-four isolates were analysed for the main oenological characteristics such as fermentative vigour with and without sulphites, sugar consumption and production of alcohol, volatile acidity, hydrogen sulphide, glycerol and ß-glucosidase. This analysis identified Kluyveromyces marxianus (seldomly used in winemaking) as the most interesting candidate yeast for the production of innovative wines. SIGNIFICANCE AND IMPACT OF THE STUDY: In recent years, interest is growing for wine production by non-Saccharomyces yeasts, both in research and in the industry. This study describes the yeast population of the grapes in a small-secluded island in the Mediterranean Sea, useful site for the search of new strains. Evaluation of fundamental oenological characters identifies potential best yeasts to assay in experimental vinifications. We also describe, for the first time, 14 new colony morphologies on WL Nutrient Agar, culture medium used to monitor the yeast population dynamics.


Asunto(s)
Vitis/microbiología , Vino/microbiología , Levaduras/clasificación , Levaduras/aislamiento & purificación , Etanol/análisis , Etanol/metabolismo , Fermentación/genética , Glicerol/análisis , Glicerol/metabolismo , Islas del Mediterráneo , Mar Mediterráneo , Tipificación Molecular , Técnicas de Tipificación Micológica , Sulfitos/análisis , Sulfitos/metabolismo , Vino/análisis , Levaduras/genética
2.
Homo ; 58(1): 13-32, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17241630

RESUMEN

The present study describes human skeletal remains from Riparo della Rossa, a rock shelter in the Marche region (Central Italy). The remains consist of a cranial vault and a few non-articulated postcranial bones, possibly belonging to the same adult individual. As the cranial vault showed some morphological features that are unusual for a modern human (marked prominence of the supraorbital region, very prominent nasal bones and rather high thickness of the vault), an accurate anthropological analysis and quantification of the antiquity of the bones were required. The remains were dated with two different absolute dating methods, AMS (14)C and (235)U-(231)Pa non-destructive gamma-ray spectrometry (NDGRS), which produced discordant results: the uncalibrated (14)C dating produced 5690 +/- 80 BP for the cranial vault and 6110 +/- 80 BP for the clavicle; the NDGRS dating produced 10,000 +/- 3000 BP for the cranial vault. The sex discriminant morphological characters on the skull are not unequivocal, though the masculine ones appear more evident. The aims of the present paper are: to provide a morphological and metric description of the remains; to interpret their unusual morphological features; to attempt to attribute them to male or female sex and to one of the possible prehistoric cultural groups, according to dating results (Upper Palaeolithic, Mesolithic or Neolithic). The attribution was obtained by a Bayesian procedure taking into account the reliability of the combined information of morphological/metric features and absolute dating results. The results suggest that the Riparo della Rossa remains are best attributed to a male individual of the Neolithic age.


Asunto(s)
Huesos/anatomía & histología , Fósiles , Paleontología/métodos , Animales , Teorema de Bayes , Radioisótopos de Carbono , Hominidae/anatomía & histología , Humanos , Italia , Masculino , Reproducibilidad de los Resultados , Espectrometría gamma/métodos
3.
J Clin Endocrinol Metab ; 86(10): 4674-8, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11600524

RESUMEN

A cross-sectional study on young dancers and exdancers was performed to evaluate the effects of intense weight-bearing exercise and dietary restriction, started during puberty, on bone mineral density (BMD), menarche age, menstrual function, and gonadotropin structure. Twenty current dancers (group 1) and 9 exdancers (group 2) were compared with a control group of 30 age-matched, regularly cycling women. Body weight, body mass index, total daily caloric intake, and nutritional markers were significantly lower (P < 0.05) in groups 1 and 2 than in controls. Using Quantitative Computed Tomography for the BMD evaluation, 12 dancers and 5 exdancers had Z-scores less than 2.5 SD below the mean of the controls; whereas, in 6 dancers and in 2 exdancers, BMD was between 1 and 2.5 SD. Groups 1 and 2 had a delay of menarche, which correlated positively with years of dance before menarche (r = 0.8; P < 0.001). Dancers had low levels and altered structure of circulating gonadotropins, which improved after GnRH stimulation. In conclusion, ballet training performed by dancers during puberty, dietary restriction, and low body mass index can all be associated with reduction in BMD and altered gonadotropin isoforms, with subsequent delay of menarche, menstrual dysfunctions, and insufficient peak bone mass. A longitudinal study must be conducted to confirm the persistence of low lumbar spine bone density in adult age.


Asunto(s)
Densidad Ósea , Ejercicio Físico , Adulto , Estudios Transversales , Ingestión de Energía , Femenino , Hormona Folículo Estimulante/sangre , Hormona Liberadora de Gonadotropina/farmacología , Humanos , Hormona Luteinizante/sangre
4.
Health Phys ; 68(1): 71-9, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7989198

RESUMEN

We have used the impedance method to calculate the induced electric (E) fields and current densities (J) for the spatially varying vector magnetic fields due to a hair dryer. In this method, applicable for low-frequency exposures where the quasi-static approximation may be made, the biological body or the exposed parts thereof are represented by a three-dimensional (3-D) network of impedances whose individual values are obtained from the electrical properties sigma, epsilon r for the various tissues. We have measured the 3-D variations of the 50-Hz magnetic fields from a typical hair dryer and found that the various components correlate well with those for a helical coil. The non-uniform magnetic fields thus obtained are used to calculate the induced E and J with a resolution of 1.31 cm for the model of the head and neck. The induced E values are compared with the fields endogenous to the body and the minimum detectable E-field limits based on the cellular thermal noise model proposed by Weaver and Astumian (1990, 1992).


Asunto(s)
Campos Electromagnéticos , Cabeza , Humanos , Modelos Estructurales
5.
Radiat Prot Dosimetry ; 111(4): 429-33, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15550716

RESUMEN

The paper illustrates the limits and performances of different experimental monitoring techniques, which are applied to digitally modulated radiofrequency electromagnetic fields used for mobile telecommunications. Different experimental set-ups have been developed, verified and applied for the analysis and characterisation of wide band probes and narrow band measuring procedures.


Asunto(s)
Teléfono Celular , Campos Electromagnéticos , Exposición a Riesgos Ambientales/análisis , Ondas de Radio , Radiometría/métodos , Programas Informáticos , Algoritmos , Análisis de Falla de Equipo , Italia , Modelos Estadísticos , Monitoreo de Radiación/instrumentación , Monitoreo de Radiación/métodos , Radiometría/instrumentación , Reproducibilidad de los Resultados , Medición de Riesgo/métodos , Factores de Riesgo , Sensibilidad y Especificidad , Integración de Sistemas , Interfaz Usuario-Computador
6.
Radiat Prot Dosimetry ; 111(4): 339-42, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15550698

RESUMEN

This paper aims to validate a ray-tracing model for electromagnetic field calculation, which is used in urban environments to predict irradiation from radio base stations for population exposure evaluation. Validation was carried out through a measurement campaign by choosing measurement points in order to test different propagation environments and analysing broadcast control channels through narrow band measurements. Comparison of the calculated and measured fields indicates that the ray-tracing model used calculates electric field with good accuracy, in spite of the fact that the propagation environment is not described in detail, because of difficulties in modelling the geometrical and electrical characteristics of urban areas. Differences between the calculated and measured results remain below 1.5 dB, with a mean value of 1 dB.


Asunto(s)
Algoritmos , Ciudades , Campos Electromagnéticos , Monitoreo de Radiación/métodos , Radiometría/métodos , Medición de Riesgo/métodos , Telecomunicaciones , Italia , Análisis Numérico Asistido por Computador , Dosis de Radiación , Ondas de Radio , Reproducibilidad de los Resultados , Factores de Riesgo , Sensibilidad y Especificidad , Programas Informáticos , Topografía Médica/métodos
7.
Radiat Prot Dosimetry ; 111(4): 349-53, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15550700

RESUMEN

In this work, the electromagnetic interference on hearing aids was evaluated. Electromagnetic (EM) immunity tests on different types of hearing aids were carried out, using signals of intensity and modulation comparable to those present in the environment. The purpose of this work is to characterise the interference, establishing the immunity threshold for different frequencies and finding out which types of hearing aids are more susceptible, and in which frequency range. The tests were carried out in a GTEM cell on seven hearing aids, using AM and GSM signals in the radiofrequency (RF) range.


Asunto(s)
Teléfono Celular , Campos Electromagnéticos , Contaminación Ambiental/análisis , Análisis de Falla de Equipo/métodos , Falla de Equipo , Audífonos , Ondas de Radio , Análisis de Falla de Equipo/instrumentación , Monitoreo de Radiación , Protección Radiológica/instrumentación , Protección Radiológica/métodos
8.
Radiat Prot Dosimetry ; 97(4): 363-8, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11878421

RESUMEN

After a brief description of the reference systems for the calibration of the electromagnetic field meters set up at IEN and the Ivrea Department of ARPA, the procedures for the evaluation of the measurement uncertainty are discussed, with reference to the problem of identifying and quantifying the different uncertainty components. which are due both to the field meter characteristics and to the measurement procedure and conditions. The problem of how to compare a measurement result, which consists of the measurement value and its associated uncertainty, with a limit fixed by the standards is also faced.


Asunto(s)
Calibración , Campos Electromagnéticos , Exposición a Riesgos Ambientales/análisis , Monitoreo de Radiación/normas , Contaminación Ambiental , Humanos
9.
Radiat Prot Dosimetry ; 94(4): 375-80, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11499442

RESUMEN

Classification of 'exposed/non-exposed' subjects in epidemiological studies concerning the possible cancer risk associated with ELF magnetic field exposure is based on the a priori assumption of magnetic field value cut-off points that, often, are defined equal to minimum exposure levels typical of a population residing near high voltage facilities (0.1-4.2 microT), but in some cases an environmental magnetic field level not associated with transmission lines can exist. The results of an ELF magnetic field survey in an Italian urban area (about 1 million inhabitants) are presented: average field levels are correlated with population density of different districts. Exposure indexes are obtained, which are compared with those evaluated in studies regarding domestic exposure: background average levels result in comparable to cut-off points in epidemiological studies, but in some districts with high population density, they are much higher. This shows that knowledge of background magnetic field level in urban areas can assume a significant role in exposure assessment.


Asunto(s)
Campos Electromagnéticos , Monitoreo de Radiación/métodos , Radiación de Fondo , Humanos , Italia , Mapas como Asunto , Dosis de Radiación , Estadística como Asunto , Salud Urbana
10.
Radiat Prot Dosimetry ; 97(4): 355-8, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11878419

RESUMEN

Electromagnetic radiation, which is used by broadcasting and mobile telephone systems to transmit information, permeates the city environment. In order to properly evaluate population exposure to electromagnetic fields, knowledge of their intensity and spectral components is necessary. In this study the results of radiofrequency field monitoring carried out in Torino, a large town located in the north-west of Italy are shown: the variation of the electromagnetic field strength is evaluated as a function of the height from the ground, the location in the urban area and the frequency. separating the contributions of the different sources (broadcasting antennas and radio base stations for mobile phones). Furthermore, the contribution of the radio base stations is theoretically evaluated, adding the emissions off all installations situated in Torino and examining the field strength maps calculated, considering the orography, for different heights. The theoretical values are also compared with those measured in the frequency range of mobile telephony emissions.


Asunto(s)
Campos Electromagnéticos/efectos adversos , Exposición a Riesgos Ambientales/análisis , Monitoreo de Radiación/métodos , Ondas de Radio/efectos adversos , Radiación de Fondo , Humanos , Italia , Modelos Teóricos , Vigilancia de la Población , Salud Pública , Teléfono , Población Urbana
11.
Radiat Prot Dosimetry ; 97(4): 405-8, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11878429

RESUMEN

Based on the numerical determination of the complete irradiation volume of a commercial RBS antenna--performed using the FDTD method and the Kirchhoff integral formula for near to far field transformation--open site estimations of the electric field are made and compared with experimentally measured values. To describe the actual behaviour of the radiation field, the inherently complex phasic nature of plane waves is taken into account, together with their two independent states of polarisation. This information is contained in the radiation pattern previously deduced. Moreover, a reflected contribution from flat ground is introduced, along with the line-of-sight ray. Amplitude and phase of the reflected wave are calculated using Fresnel formulae for stratified ground and two polarisation states, i.e. normal and parallel to the plane of incidence. Good agreement with measured values is achieved only by using such assumptions.


Asunto(s)
Campos Electromagnéticos , Exposición a Riesgos Ambientales/análisis , Modelos Teóricos , Ondas de Radio , Dispersión de Radiación , Humanos , Análisis Numérico Asistido por Computador , Dosis de Radiación , Radiometría/métodos
12.
Homo ; 61(6): 385-412, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20979998

RESUMEN

The aim of this work is to explore the pattern of craniofacial morphometric variation and the relationships among five prehistoric Sardinian groups dated from Late Neolithic to the Nuragic Period (Middle and Late Bronze Age), in order to formulate hypotheses on the peopling history of Sardinia. Biological relationships with coeval populations of central peninsular Italy were also analysed to detect influences from and towards extra-Sardinian sources. Furthermore, comparison with samples of contemporary populations from Sardinia and from continental Italy provided an indication of the trend leading to the final part of the peopling history. Finally, Upper Palaeolithic and Mesolithic samples were included in the analyses to compare the prehistoric Sardinians with some of their potential continental ancestors. The analysis is based on multivariate techniques including Mahalanobis D(2) distance, non-parametric multidimensional scaling (MDS) and principal component analysis (PCA). The results showed the tendency to progressive differentiation between Sardinian groups and peninsular Italian groups, with the possible exception of a discontinuity showed by the Bonnànaro (Early Bronze Age) Sardinian sample. Several aspects of the morphological results were found to agree with the current genetic evidence available for the present-day Sardinian population and a Nuragic sample: (1) biological divergence between the Sardinian and peninsular Italian populations; (2) similarity/continuity among Neolithic, Bronze Age and recent Sardinians; (3) biological separation between the Nuragic and Etruscan populations; (4) contribution of a Palaeo-Mesolithic gene pool to the genetic structure of current Sardinians.


Asunto(s)
Fósiles , Paleontología , Cráneo/anatomía & histología , Adulto , Niño , Femenino , Historia Antigua , Humanos , Italia , Masculino
14.
Radiat Prot Dosimetry ; 137(3-4): 197-200, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19880416

RESUMEN

In this work the compliance of tanning lamps with technical standards EN 60335-2-27 'Household and similar electrical appliances-Safety. Part 2: Particular requirements for appliances for skin exposure to ultraviolet and infrared radiation' was analysed. Results of this analysis showed that none of the examined technical documentation produced by the lamps manufacturers is fully compliant with the standard technique. Furthermore data reported in the same manuals, such as effective radiant exposure or irradiance, would indicate that these sources may be the cause of undue exposure to ultraviolet (UV) radiation. For this reason a measurement campaign on UV lamps used in tanning salons was organised. The first results of these measurements seem to confirm the doubts raised from the analysis of the lamp manuals: the use of a tanning lamp can lead to UV radiation exposure levels higher than reference maximum values recommended by EN 60335-2-27.


Asunto(s)
Adhesión a Directriz , Iluminación/instrumentación , Iluminación/normas , Radiometría/normas , Bronceado , Terapia Ultravioleta/instrumentación , Terapia Ultravioleta/normas , Diseño de Equipo , Análisis de Falla de Equipo , Unión Europea , Guías como Asunto , Italia , Rayos Ultravioleta
15.
Bioelectromagnetics ; 12(1): 35-45, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-2012620

RESUMEN

Extremely-low-frequency (ELF) and very-low-frequency (VLF) magnetic fields as emitted by monochrome and multichrome video display units (VDUs) were measured for their frequency domains. The rms magnetic-flux densities (MFDs) were measured as a function of distance from all six sides of VDUs of four types. The MFDs at a distance of 30 cm from the screen (defined as the operator's position) were between 0.06 and 0.6 microT in the ELF range and between 0.02 and 0.06 microT in the VLF range. The contribution of harmonics to the total MFD was the same for both frequency ranges, less than 6%. For the first three harmonics, the MFD of each higher harmonic was one-half that of the immediately lower harmonic.


Asunto(s)
Terminales de Computador , Campos Electromagnéticos
16.
Biochem Biophys Res Commun ; 217(3): 1032-8, 1995 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-8554554

RESUMEN

We had previously shown that P. lividus embryos subjected to heat shock are unable to synthesize proteins of the hsp70 family at a detectable level before the hatching blastula stage. We show here that this is not due to the inability to synthesize the hsp70 mRNAs, which are detectable following heat shock also in early stages, although in much lower amounts per embryo than in later stages. These mRNAs are also translated, as judged by the facts that they are present in the polysomal pellet, and that they are translatable in a cell free system. As to the question of the amount of hsp70 RNAs per nucleus, we conclude that this is also higher in later than in earlier stages. The presence of hsp70 mRNAs is already detectable after heating at 4 centigrades above 20 and their amount increases with the increase of temperature in the range between 24 degrees C and 28 degrees C.


Asunto(s)
Proteínas HSP70 de Choque Térmico/genética , Erizos de Mar/embriología , Animales , Regulación del Desarrollo de la Expresión Génica , Polirribosomas/metabolismo , Biosíntesis de Proteínas , ARN Mensajero/genética , Transcripción Genética
17.
Biochem Biophys Res Commun ; 234(1): 24-9, 1997 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-9168953

RESUMEN

An antiserum against a hsp of the 70-kDa family was prepared, by means of a fusion protein, which was able to detect a constitutive 75-kDa hsc in the sea urchin P. lividus. This hsc was present both during oogenesis and at all developmental stages. A two-dimensional electrophoresis has revealed four isolectric forms of this 75-kDa hsc. The amino acid sequence of the fragment used to prepare the anti-hsp70 antibodies revealed a 43% identity with the corresponding part of sea urchin sperm receptor, and in mature eggs a brighter immunofluorescence was seen all around the cell cortex where the receptor for sea urchin sperm is localized. In oocytes the hsp75 was localized in the cytoplasms but not in the nuclei. In the embryos a higher hsp75 concentration was found in the portion facing the lumen of the cells which invaginate at gastrulation.


Asunto(s)
Embrión no Mamífero/química , Proteínas HSP70 de Choque Térmico/análisis , Secuencia de Aminoácidos , Animales , Western Blotting , Citoplasma/química , Electroforesis en Gel de Poliacrilamida , Desarrollo Embrionario , Femenino , Proteínas HSP70 de Choque Térmico/química , Inmunohistoquímica , Punto Isoeléctrico , Masculino , Datos de Secuencia Molecular , Peso Molecular , Oocitos/química , Oogénesis , Ovario/citología , Plásmidos/genética , Receptores de Superficie Celular/química , Receptores de Superficie Celular/metabolismo , Proteínas Recombinantes de Fusión , Erizos de Mar , Homología de Secuencia de Aminoácido , Espermatozoides/química
18.
Cell Biol Int ; 22(2): 91-4, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9878095
19.
Bioelectromagnetics ; 16(6): 356-64, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8789066

RESUMEN

Magnetic fields emitted by electric appliances such as razors, hair dryers, and drills were measured in the frequency domain. Results show the presence of high-frequency components (up to 96 kHz for razors, up to 3.4 kHz for hair dryers, and up to 8.6 kHz for drills) in the harmonic content of the fields. The measured fields were used to calculate the induced current densities in an anatomically based model of the human head (resolution 1.31 cm) by using the impedance method. The harmonic field contribution to the current density was higher than that from the carrier frequency for all the tested appliances.


Asunto(s)
Electrónica/instrumentación , Magnetismo/efectos adversos , Cabeza , Humanos , Modelos Anatómicos , Análisis Espectral
20.
Dev Biol ; 228(2): 270-86, 2000 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-11112329

RESUMEN

New technologies for isolating differentially expressed genes from large arrayed cDNA libraries are reported. These methods can be used to identify genes that lie downstream of developmentally important transcription factors and genes that are expressed in specific tissues, processes, or stages of embryonic development. Though developed for the study of gene expression during the early embryogenesis of the sea urchin Strongylocentrotus purpuratus, these technologies can be applied generally. Hybridization parameters were determined for the reaction of complex cDNA probes to cDNA libraries carried on six nylon filters, each containing duplicate spots from 18,432 bacterial clones (macroarrays). These libraries are of sufficient size to include nearly all genes expressed in the embryo. The screening strategy we have devised is designed to overcome inherent sensitivity limitations of macroarray hybridization and thus to isolate differentially expressed genes that are represented only by low-prevalence mRNAs. To this end, we have developed improved methods for the amplification of cDNA from small amounts of tissue (as little as approximately 300 sea urchin embryos, or 2 x 10(5) cells, or about 10 ng of mRNA) and for the differential enhancement of probe sequence concentration by subtractive hybridization. Quantitative analysis of macroarray hybridization shows that these probes now suffice for detection of differentially expressed mRNAs down to a level below five molecules per average embryo cell.


Asunto(s)
Embrión no Mamífero/fisiología , Regulación del Desarrollo de la Expresión Génica , Biblioteca de Genes , Análisis de Secuencia por Matrices de Oligonucleótidos , Erizos de Mar/embriología , Erizos de Mar/genética , Animales , Animales Modificados Genéticamente , Sondas de ADN , ADN Complementario , Genes Reporteros , Proteínas Fluorescentes Verdes , Proteínas Luminiscentes/análisis , Proteínas Luminiscentes/genética , ARN Mensajero/genética , Factores de Transcripción/metabolismo
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