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1.
Environ Pollut ; 286: 117489, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34119860

RESUMO

The Menor sea is a coastal lagoon declared by the European Union as a sensitive area to eutrophication due to human activities. To control the deterioration of its water quality, it is necessary to monitor some parameters such as chlorophyll-a (chl-a), which indicates phytoplankton biomass in the water. In the study area, current efforts focus on in-situ measurements to estimate chl-a by means of a few permanent stations and seasonal oceanographic campaigns, however they are expensive and time consuming. In this work, we proposed a machine learning approach based on Sentinel-2 data to estimate chl-a content on the upper part of the water column. Random forest (rf), support vector machine (svmRadial), Artificial Neural Network (ANN) and Deep Neural Network (DNN) algorithms were utilized under three feature selection scenarios, and several spectral indices were used in combination with Sentinel 2 bands. Rf, svmRadial and DNN performed better when all the available predictors were included in the models (RMSE = 0.82, 0.82 and 1.76 mg/m3 respectively), whereas ANN achieved better results under scenario c (principal components). Our results demonstrate the possibility to estimate chl-a concentration in a cost-effective manner and thereby provide near-real time information to monitor the water quality of the Menor sea, what can be of great interest for local authorities, tourism and fishing industry.


Assuntos
Monitoramento Ambiental , Qualidade da Água , Clorofila/análise , Clorofila A/análise , Humanos , Aprendizado de Máquina , Espanha
2.
Zookeys ; 1029: 185-208, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33935556

RESUMO

The montane cloud forests of the Sierra Madre de Oaxaca (SMO) host a remarkable herpetofauna diversity and represent one of the most important areas of endemism for Mexico and Mesoamerica. Although the area has been previously studied, most of the extant records for this group are biased to locations accessed by paved roads. In addition, an important proportion of this territory is conserved by Indigenous and Community Conservation Areas (ICCA), but little information of the species occurring within these areas exists. Therefore, information on the distribution of many endemic taxa in this region to date is either underestimated or incomplete. With the aim of increasing the ecological and distributional knowledge of this group in remote areas, we carried out field surveys in Santa Cruz Tepetotutla Oaxaca, a locality 25 km in a straight line to the closest paved road that conserves 9,670 ha of land through the ICCAs modality. Surveys were made during 2018 and 2019, including both dry and wet seasons. A total of 40 species of amphibians and reptiles were recorded: 32.5% of these records represent distributional range extensions, while 20% represent altitudinal range extensions. A total of 17.5% are records of species under a high risk category, highlighting both the relevance of studying remote areas to increase species population knowledge and the role of community conservation actions for species persistence. Finally, our records include the rediscovery of Rhadinella schistosa, a species undetected for more than 50 years.

3.
J Forensic Sci ; 66(3): 1048-1055, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33583031

RESUMO

Material characterization is essential to the provenance of graphic arts. Non-destructive analytical techniques are increasingly required in the authentication process of cultural heritage. This work presents a suite of portable, non-destructive, and complementary analytical techniques, energy dispersive x-ray fluorescence (EDXRF), Fourier transform infrared (FTIR) spectroscopies, and brightfield microscopy, applied to the analysis of historical photographs depicting São Paulo city architecture, whose registration date and process of fabrication are unknown. The EDXRF analysis emphasizes the use of typical POP (printing-out paper) photograph with baryta (BaSO4 ) coated paper substrate while the FTIR and microscopy analyses confirm the presence of collodion and a gelatin-based baryta layer. This photographic process was widely employed by professional photographers from 1889 to 1930, when it was gradually abandoned in commercial use. This time interval (1889-1930) is consistent with the information surveyed on the photographic collection. In conclusion, employing complementary techniques (elemental and molecular spectroscopies and image magnification) is essential in identifying the manufacturing materials of cultural heritage material, which is the basis of contemporary authentication procedures. These data provide to curators and historians fundamental information for cataloging, adding subsidies for the correct storage and preservation ("heritage appreciation"). Still, for professional photographers, they present information on the manufacturing processes of historical photographs. The data from the present study also emphasize its perspective of use in graphic arts to aid connoisseurship in identifying forgeries during provenance and authentication studies.

4.
Artigo em Inglês | MEDLINE | ID: mdl-33572416

RESUMO

This study aimed to evaluate the effects of treatment with Peruíbe Black Mud (PBM) on the clinical parameters and quality of life of patients with knee osteoarthritis and to compare the effects of PBM samples simply matured in seawater and PBM sterilized by gamma radiation. A controlled, double-blind trial was conducted with 41 patients divided into two treatment groups composed of 20 and 21 patients: one group was treated with matured PBM and the other with sterilized PBM. Evaluations were done using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and the Medical Outcomes Study Short Form 36 (SF-36) questionnaires, the Kellgren and Lawrence (KL) radiographic scale, and the quantification of the serum levels of inflammatory biomarkers. An improvement in pain, physical functions, and quality of life was observed in all of the patients who underwent treatment with both simply matured and sterilized PBM. Nine patients showed remission in the KL radiographic scale, but no statistically significant differences were observed in the serum levels of inflammatory mediators before or after treatment. Peruíbe Black Mud proves to be a useful tool as an adjuvant treatment for knee osteoarthritis (OA), as shown by the results of the WOMAC and SF-36 questionnaires and by the remission of the radiographic grade of some patients on the Kellgren and Lawrence scale.


Assuntos
Osteoartrite do Joelho , Negro ou Afro-Americano , Humanos , Osteoartrite do Joelho/terapia , Dor , Medição da Dor , Qualidade de Vida
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