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1.
Anal Bioanal Chem ; 416(2): 461-465, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38001374

RESUMO

The recently introduced unified pH ([Formula: see text]) concept enables rigorous pH measurements in non-aqueous and mixed media while at the same time maintaining comparability to the conventional aqueous pH scale. However, its practical application is hindered by a shortage of reference [Formula: see text] values. In order to improve this situation, the European Metrology Research Project (EMPIR) UnipHied ("Realisation of a UnipHied pH scale") launched an interlaboratory comparison among highly experienced electrochemistry expert laboratories to assign the first such reference [Formula: see text] values by adopting an extensive statistical treatment of the reported measurement data: to phosphate buffer in water-ethanol mixture (50 wt% of ethanol) and ammonium formate buffer in pure ethanol. Two different measurement setups - one capable of being easily adopted in industrial applications - have been used to demonstrate the robustness of [Formula: see text] measurement. This is an important step towards wider adoption of the [Formula: see text] concept in practice, like liquid chromatography, biofuels analysis and electrocatalysis.

2.
Radiat Prot Dosimetry ; 199(8-9): 865-871, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37225187

RESUMO

Radiofrequency (RF) exposure has grown substantially over time in the public area. Personal dosimetry measurements are intended to estimate how human RF exposure relates to exposure limits that do not pose a health risk. For our case study, an outdoor festival was chosen to assess realistic RF exposure of young adults during their entertainment. Band-selective RF exposure-sorted along 2G-4G uplinks and downlinks, 5G and Wi-Fi bands-was evaluated. Electric field strength data subsets were classified on the basis of activities as well as crowd density. 2G contributed the most to the overall RF exposure. Highest RF exposure was associated with attendance in a concert. In moderately crowded situations, RF exposure was higher than in the most crowded ones. However, the total measured electric field values were higher than in other outdoor environment, but still far below the national and international directives of regulatory RF-EMF exposure limits.


Assuntos
Meio Ambiente , Ondas de Rádio , Adulto Jovem , Humanos
3.
Int J Mol Sci ; 24(3)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36769173

RESUMO

In the human environment, the increasing exposure to radiofrequency (RF) radiation, especially that emitted by wireless devices, could be absorbed in the body. Recently, mobile and emerging wireless technologies (UMTS, DECT, LTE, and Wi-Fi) have been using higher frequencies than 2G GSM systems (900/1800 MHz), which means that most of the circulating RF currents are absorbed into the skin and the superficial soft tissue. The harmful genotoxic, cytotoxic, and mutagenic effects of solar ultraviolet (UV) radiation on the skin are well-known. This study aimed at investigating whether 2422 MHz (Wi-Fi) RF exposure combined with UV radiation in different sequences has any effect on the inflammation process in the skin. In vitro experiments examined the inflammation process by cytokines (IL-1α, IL-6, IL-8) and MMP-1 enzyme secretion in a 3D full-thickness human skin model. In the first study, UV exposure was immediately followed by RF exposure to measure the potential additive effects, while in the second study, the possible protective phenomenon (i.e., adaptive response) was investigated when adaptive RF exposure was challenged by UV radiation. Our results suggest that 2422 MHz Wi-Fi exposure slightly, not significantly increased cytokine concentrations of the prior UV exposure. We could not detect the adaptive response phenomenon.


Assuntos
Inflamação , Ondas de Rádio , Humanos , Ondas de Rádio/efeitos adversos , Raios Ultravioleta/efeitos adversos , Pele , Citocinas
4.
Artigo em Inglês | MEDLINE | ID: mdl-35483778

RESUMO

Levels of DNA damage represent the dynamics between damage formation and removal. Therefore, to better interpret human biomonitoring studies with DNA damage endpoints, an individual's ability to recognize and properly remove DNA damage should be characterized. Relatively few studies have included DNA repair as a biomarker and therefore, assembling and analyzing a pooled database of studies with data on base excision repair (BER) was one of the goals of hCOMET (EU-COST CA15132). A group of approximately 1911 individuals, was gathered from 8 laboratories which run population studies with the comet-based in vitro DNA repair assay. BER incision activity data were normalized and subsequently correlated with various host factors. BER was found to be significantly higher in women. Although it is generally accepted that age is inversely related to DNA repair, no overall effect of age was found, but sex differences were most pronounced in the oldest quartile (>61 years). No effect of smoking or occupational exposures was found. A body mass index (BMI) above 25 kg/m2 was related to higher levels of BER. However, when BMI exceeded 35 kg/m2, repair incision activity was significantly lower. Finally, higher BER incision activity was related to lower levels of DNA damage detected by the comet assay in combination with formamidopyrimidine DNA glycosylase (Fpg), which is in line with the fact that oxidatively damaged DNA is repaired by BER. These data indicate that BER plays a role in modulating the steady-state level of DNA damage that is detected in molecular epidemiological studies and should therefore be considered as a parallel endpoint in future studies.


Assuntos
Dano ao DNA , Reparo do DNA , Ensaio Cometa , Reparo do DNA/genética , DNA-Formamidopirimidina Glicosilase , Estudos Epidemiológicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
6.
Artigo em Inglês | MEDLINE | ID: mdl-32575398

RESUMO

The absorption of exposure to radiofrequency (RF) emitted by wireless devices leads to a high specific absorption rate in the skin. Ultraviolet (UV) radiation can induce several damages to the skin. The aim of this study was to examine whether combined, consecutive exposure to solar UV radiation and 1950 MHz RF exposure of third generation (3G) mobile system have any effect on inflammation processes in the skin. Under in vitro experiments, the inflammation process was examined by cytokines (IL-1α, IL-6, and IL-8) and MMP-1 enzyme secretion on 3D full thickness human skin model. The RF exposure was applied before or after UV irradiation, in order to study either the possible cooperative or protective effects of exposure to RF and UV. We did not find changes in cytokines due to exposure to RF alone. The RF exposure did not enhance the effects of UV radiation. There was a statistically not-significant decrease in cytokines when the skin tissues were pre-exposed to RF before being exposed to 4 standard erythemal dose (SED) UV compared to UV exposure alone. We found that RF exposure reduced the previously UV-treated MMP-1 enzyme concentration. This study might support the evaluation of the effects on the skin exposed to microwave radiation of 5G mobile technology.


Assuntos
Telefone Celular , Inflamação , Ondas de Rádio , Raios Ultravioleta , Citocinas/metabolismo , Humanos , Modelos Biológicos , Ondas de Rádio/efeitos adversos , Pele , Raios Ultravioleta/efeitos adversos
7.
Sensors (Basel) ; 20(9)2020 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-32370283

RESUMO

High altitude aerial surveys have the potential to improve disturbance-free data collection in wildlife research, but previously, bird species were not recognizable in high-altitude orthophotos. This method of aerial surveying is effective and can be repeated frequently due to its low cost; it also has the additional advantage of being able to monitor the status of protected areas. In the case of waterbirds, due to the low vegetation coverage, aerial remote sensing is an exceptionally effective technique for surveying populations and detecting nests. Aerial surveys made at low altitudes can cause serious stress for birds. The method we developed and employed is unlikely to be detected by either ground-based or nesting birds but is far more reliable compared to the low-resolution imaging methods and to the evaluation of non-georeferenced photo series. The modern sensors and photogrammetric procedures enable the use of the present method worldwide; furthermore, the large-scale ortho image-derived information has become obtainable more frequently. Direct georeferencing makes the field geodetic survey unnecessary. Orthophotos with a 0.7 cm spatial resolution allow us to reliably identify even the individuals of smaller species, and by the use of oblique images, they can be tracked from two or four different directions.


Assuntos
Aves , Monitoramento Ambiental , Tecnologia de Sensoriamento Remoto , Altitude , Animais , Ecossistema , Inquéritos e Questionários
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