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1.
Opt Express ; 23(7): 8476-88, 2015 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-25968686

RESUMO

A new method for the data fusion of atmospheric vertical profiles, referred to as complete fusion, is presented. Using the measurements of the MIPAS instrument, the performance of the method is compared with those of weighted and arithmetic means. The complete fusion perfectly reproduces the results of the simultaneous retrieval with equal error estimates and number of degrees of freedom, while arithmetic and weighted means have relatively low vertical resolution and differ from the simultaneous retrieval by more than their errors. In addition the problem posed in this context by systematic errors is analyzed and alleviating procedures are considered.

2.
Opt Express ; 22(20): 24808-16, 2014 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-25322055

RESUMO

A new method to perform averages of atmospheric vertical profiles is presented. The method allows changing a-posteriori the strength of the constraint used in the retrievals of the single profiles with the purpose of optimizing the trade-off between measurement error and vertical resolution. The method is used to calculate averages of HCFC-22 profiles retrieved from MIPAS observations, demonstrating the possibility of correctly obtaining retrievals with smaller constraints (that is: having at least a factor ten greater errors) and more degrees of freedom by up to a factor two.

3.
Environ Sci Pollut Res Int ; 31(24): 35779-35788, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38744760

RESUMO

Studies on functional traits of aquatic communities are useful for understanding the ecosystem dynamics as well as the diversity of ecological niches. Here, we characterize zooplankton functional groups and which limnological factors are responsible to changes in traits. Water samples were collected to evaluate limnological parameters and vertical hauls with plankton net (68 µm) were performed to characterize the community in seven reservoirs (Itupararanga, Atibainha, Salto Grande, Rio Grande, Igaratá, Barra Bonita, and Broa, São Paulo state, Brazil). Each species identified was classified according to a trophic group, reproduction mode, body length, habitat, and feeding habitats. Our results showed a predominance of pelagic suspensory herbivores with cilia (31%) followed by pelagic herbivore suspension filter feeders (17%) and raptorial omnivores (15.38%). The other individuals were categorized as pelagic herbivore suspension with oral device (12.3%), littoral herbivores suspensive with cilia (12.3%), pelagic-sucking herbivores (9.2%), and littoral grazing herbivores (3%). The dominance of herbivores may be influenced by the availability of nutrients, influencing their food sources. The abundance of omnivores engaged in predatory behavior can be attributed to disponible prey, thereby exerting significant repercussions on the organization of biological communities.


Assuntos
Biodiversidade , Zooplâncton , Brasil , Zooplâncton/classificação , Animais , Ecossistema , Lagos , Comportamento Alimentar/fisiologia
4.
Chemosphere ; 311(Pt 1): 136984, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36306964

RESUMO

Cytosolic phospholipase A2 (cPLA2) belongs to a large family of proteins and plays a crucial role in the regulation of arachidonic acid metabolism and inflammation cascade in zebrafish (Danio rerio). This enzyme with a molecular weight of 85 kDa, has two distinct domains. One is the regulatory and calcium-dependent (Ca2+) domain called C2, the other is the catalytic α/ß hydrolase Ca2+-independent domain, where serine and aspartic acid catalytic dyad residues are present. We investigated the interaction of malathion and their organophosphate metabolites in the cPLA2 using in silico tools. Molecular docking results showed hydrophobic interactions with the paraoxon and catalytic site residue (Ser 223). Malathion increases intracellular Ca2+ due to endoplasmic reticulum influx which in turn activities phospholipase A2 and arachidonic acid release. Molecular docking and homology modelling of proteins and ligands could be a complementary tool for ecotoxicology and environment pollution assessment.


Assuntos
Malation , Peixe-Zebra , Animais , Peixe-Zebra/metabolismo , Citosol , Malation/toxicidade , Malation/metabolismo , Ácido Araquidônico/metabolismo , Simulação de Acoplamento Molecular , Fosfolipases A2/metabolismo , Cálcio/metabolismo , Fosfolipases A2 Citosólicas/metabolismo
5.
Opt Express ; 20(5): 5151-67, 2012 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-22418321

RESUMO

A quality quantifier, referred to as measurement quality quantifier (MQQ), is proposed for indirect measurements. It satisfies the property that the MQQ of the data fusion of two or more independent measurements is the sum of the MQQs of the individual measurements and can also be determined in absolute terms for ill-posed problems. It is calculated from the covariance and Jacobian matrices of the observations, but the same result is also obtained using the covariance and averaging kernel matrices of the retrieved quantities. In the case of measurements of a continuous distribution a quantifier that provides the information distribution can be derived from the MQQ. The proposed quantifiers are herewith used for the quality assessment of atmospheric ozone measurements performed by IASI and MIPAS instruments.


Assuntos
Algoritmos , Atmosfera/análise , Atmosfera/química , Interpretação Estatística de Dados , Monitoramento Ambiental/métodos , Modelos Estatísticos , Ozônio/análise , Simulação por Computador
6.
Opt Express ; 19 Suppl 3: A340-60, 2011 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-21643376

RESUMO

The trend of stratospheric water vapor as a function of latitude is estimated by the MIPAS measurements by means of a new method that uses the measurement space solution. The method uses all the information provided by the observations avoiding the artifacts introduced by the a priori information and by the interpolation to different vertical grids. The analysis provides very precise values of the trends that, however, are limited by a relatively large systematic error induced by the radiometric calibration error of the instrument. The results show in the five years from 2005 to 2009 a dependence on latitude of the stratospheric (from 37 to 53 km) water vapor trend with a positive value of (0.41 ± 0.16)%yr-1 in the northern hemisphere and less than 0.16%yr-1 in the southern hemisphere.

7.
Rend Lincei Sci Fis Nat ; 31(3): 505-537, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32837713

RESUMO

ABSTRACT: We review the state of knowledge on the bio-fluid dynamic mechanisms involved in the transmission of the infection from SARS-CoV-2. The relevance of the subject stems from the key role of airborne virus transmission by viral particles released by an infected person via coughing, sneezing, speaking or simply breathing. Speech droplets generated by asymptomatic disease carriers are also considered for their viral load and potential for infection. Proper understanding of the mechanics of the complex processes whereby the two-phase flow emitted by an infected individual disperses into the environment would allow us to infer from first principles the practical rules to be imposed on social distancing and on the use of facial and eye protection, which to date have been adopted on a rather empirical basis. These measures need compelling scientific validation. A deeper understanding of the relevant biological fluid dynamics would also allow us to evaluate the contrasting effects of natural or forced ventilation of environments on the transmission of contagion: the risk decreases as the viral load is diluted by mixing effects but contagion is potentially allowed to reach larger distances from the infected source. To that end, our survey supports the view that a formal assessment of a number of open problems is needed. They are outlined in the discussion.

8.
Opt Express ; 17(7): 4944-58, 2009 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-19333254

RESUMO

A procedure for the optimal utilization and representation of the information retrieved from atmospheric observations is discussed. We show that the "measurement-space solution" exclusively contains the information present in the observations, but is not suitable for a representation of the retrieved profile in the form of a graph. The new method of the "null-space regularization", which provides in a complement space an external constraint and makes the solution compliant with this representation, is presented. In this way the measurement and the constraint are separately determined and are given in a vertical grid that can be freely chosen as fine as desired. The method is applied to simulated measurements and is used to define a procedure for data fusion.


Assuntos
Algoritmos , Atmosfera/análise , Atmosfera/química , Monitoramento Ambiental/métodos , Modelos Químicos , Simulação por Computador
9.
Opt Express ; 16(20): 15816-33, 2008 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-18825219

RESUMO

The paper presents a novel methodology to retrieve the foreign-broadened water vapor continuum absorption coefficients in the spectral range 240 to 590 cm(-1) and is the first estimation of the continuum coefficient at wave numbers smaller than 400 cm(-1) under atmospheric conditions. The derivation has been accomplished by processing a suitable set of atmospheric emitted spectral radiance observations obtained during the March 2007 Alps campaign of the ECOWAR project (Earth Cooling by WAter vapor Radiation). It is shown that, in the range 450 to 600 cm(-1), our findings are in good agreement with the widely used Mlawer, Tobin-Clough, Kneizys-Davies (MT CKD) continuum. Below 450 cm(-1) however the MT CKD model overestimates the magnitude of the continuum coefficient.


Assuntos
Óptica e Fotônica , Água/química , Algoritmos , Atmosfera , Análise de Fourier , Gases , Modelos Estatísticos , Modelos Teóricos , Espectrofotometria Infravermelho/métodos , Temperatura
10.
J. Health Sci. Inst ; 41(2): 85-88, apr-jun 2023. Tabelas
Artigo em Português | LILACS | ID: biblio-1531186

RESUMO

Objetivo ­ Realizar análises bromatológicas de umidade, proteínas, pH e cinzas em missôs artesanais. A fermentação é um processo biotecnológico que tem sido utilizado para modificar e produzir alimentos desde a antiguidade. Nas últimas duas décadas, o interesse nos efeitos benéficos dos fermentados na saúde humana aumentou e tornou essa categoria de alimentos cada vez mais popular principalmente no Oriente. No mercado há uma ampla variedade de pastas à base de soja fermentada por microorganismos sendo conhecido popularmente como missô. Métodos ­ As análises realizadas foram secagem direta em estufa a 105°C graus para determinação da umidade (%) e calcinação em mufla para cinzas (%), determinação de pH por meio do peagâmetro e análise de proteínas através do teste de Biureto. Resultados ­ No presente estudo as amostras obtiveram um teor de umidade entre 52,71% a 60,48%, teor de cinzas variando de 1,12% a 22,7%, pH entre 5,35 e 8,68, e um teor de proteínas variando de 11,1% a 13,2%. Discussão ­ Foi interpretado e comparado os resultados obtidos com as análises de outros estudos, além disso, apontado algumas questões do campo bromatológico das pesquisas dos estudos comparados e as limitações do presente trabalho. Conclusão ­ O processo fermentativo de alimentos com microorganismos resulta em um produto diferenciado que pode ser benéfico a saúde com diferentes características organolépticas. Nossos resultados foram parcialmente semelhantes com outras pesquisas sendo que


Assuntos
Humanos , Glycine max , Fermentação , Análise de Alimentos , Proteínas
11.
Opt Lett ; 32(10): 1329-31, 2007 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-17440577

RESUMO

Apodization, which is a tool frequently used for cosmetic representation and efficient modeling of a spectrum, is now also adopted in techniques for the quantitative retrieval of parameters from observed spectra. Whether apodization can help in quantitative spectroscopy is the subject of debate in the literature. We find that, when the considered spectral range is wide enough to accurately model the instrument line shape, the same results can be obtained with and without apodization of the spectrum. However, when a truncation error is introduced by the limited extension of the modeled spectral interval, apodization can efficiently reduce this error. Therefore it is possible to save computing time by using apodization.

12.
Opt Lett ; 31(7): 855-7, 2006 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-16599190

RESUMO

Intercomparison of atmospheric measurements is often a difficult task because of the different spatial response functions of the experiments considered. We propose a new method for comparison of two atmospheric profiles characterized by averaging kernels with different vertical resolutions. The method minimizes the smoothing error induced by the differences in the averaging kernels by exploiting an optimal interpolation rule to map one profile into the retrieval grid of the other. Compared with the techniques published so far, this method permits one to retain the vertical resolution of the less-resolved profile involved in the intercomparison.

13.
Appl Opt ; 44(14): 2870-8, 2005 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-15943341

RESUMO

In preparation for a possible space mission, a breadboard version named REFIR-BB of the Radiation Explorer in the Far Infrared (REFIR) instrument has been built. The REFIR is a Fourier-transform spectrometer with a new optical layout operating in the spectral range 100-1100 cm(-1) with a resolution of 0.5 cm(-1), a 7-s acquisition time, and a signal-to-noise ratio of better than 100. Its mission is the spectral measurement in the far infrared of the Earth's outgoing emission, with particular attention to the long-wavelength spectral region, which is not covered by either current or planned space missions. This measurement is of great importance for deriving an accurate estimate of the radiation budget in both clear and cloudy conditions. The REFIR-BB permits the trade-off among all instrument parameters to be studied, the optical layout to be tested, and the data-acquisition strategy to be optimized. The breadboard could be used for high-altitude ground-based campaigns or could be flown for test flights on aircraft or balloon stratospheric platforms. The breadboard's design and the experimental results are described, with particular attention to the acquisition strategy and characterization of the interferometer. Tests were performed both in laboratory conditions and in vacuum. Notwithstanding a loss of efficiency above 700 cm(-1) caused by the poor performance of the photolithographic polarizers used as beam splitters, the results demonstrate the feasibility of using the spectrometer for space applications.

14.
Appl Opt ; 42(32): 6465-73, 2003 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-14650489

RESUMO

The validation of atmospheric remote-sensing measurements involves the comparison of vertical profiles of atmospheric constituents obtained by different instruments. This operation is a complex one because it has to take into account the measurement errors that are described by the variance-covariance matrices and the different features of the two observing systems that are described by the averaging kernels. The procedure is discussed and a method of comparison that is rigorous and does not involve degradation of the available information is developed by use of the formalism of functional spaces. The functional spaces that can be used for representation of the two profiles are reviewed, and criteria are determined for the choice of the most convenient functional space to minimize degradation of the measurements. Once the functional spaces are chosen, the components of the profiles are compared in the intersection space of these two functional spaces. If the intersection space coincides with the null vector, a pseudointersection space with useful geometrical properties can be used instead. A test of the method is made with a realistic simulation. In the test the profiles retrieved by two real instruments are simulated and quantitatively compared.

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