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1.
ACS Appl Mater Interfaces ; 15(8): 10371-10382, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36786554

RESUMO

Malignant ascites (MA) is a common symptom of peritoneal metastasis in liver cancer. Cancer immunotherapy can modulate immune cells to induce antitumor immune efficiency. Reprogramming tumor immune microenvironment (TIME) is a momentous strategy to overcome immunosuppression and achieve immune functional normalization. Inspired by the inherent apoptotic bodies and vesicles, we proposed and systematically studied engineered apoptosis-bioinspired nanoparticles (EBN) for cancer immunotherapy of MA. Using both in vitro and in vivo experimental validations, we elucidated that EBN could be efficiently engulfed by the tumor-associated macrophages (TAMs) and manipulate their polarization. Moreover, a boosted immune cascade response as a result of heightening cytotoxic T-lymphocytes (CTLs) activity was investigated. Based on these results, EBN was confirmed to have strong immune cascade activation capability. Remarkably, the injection of EBN further reduced ascites volume and reformed immune cell subtypes, compared to the injection of either PBS or free TMP195 alone. In short, this novel nanodrug delivery system (NDDS) represents a prospective immunotherapeutic approach for clinical therapeutics of hepatoma ascites and other malignant effusion.


Assuntos
Neoplasias Hepáticas , Nanopartículas , Neoplasias Peritoneais , Humanos , Ascite/patologia , Estudos Prospectivos , Macrófagos , Imunoterapia/métodos , Neoplasias Hepáticas/tratamento farmacológico , Apoptose , Microambiente Tumoral
3.
Front Mol Biosci ; 9: 983840, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36120553

RESUMO

Liver cancer is an extraordinarily heterogeneous malignant disease. The tumor microenvironment (TME) and tumor-associated macrophages (TAMs) are the major drivers of liver cancer initiation and progression. It is critical to have a better understanding of the complicated interactions between liver cancer and the immune system for the development of cancer immunotherapy. Based on the gene expression profiles of tumor immune infiltration cells (TIICs), upregulated genes in TAMs and downregulated genes in other types of immune cells were identified as macrophage-specific genes (MSG). In this study, we combined MSG, immune subtypes, and clinical information on liver cancer to develop a tumor immune infiltration macrophage signature (TIMSig). A four-gene signature (S100A9, SLC22A15, TRIM54, and PPARGC1A) was identified as the TAM-related prognostic genes for liver cancer, independent of multiple clinicopathological parameters. Survival analyses showed that patients with low TIMSig had a superior survival rate than those with high TIMSig. Additionally, clinical immunotherapy response and TIMSig was observed as highly relevant. In addition, TIMSig could predict the response to chemotherapy. Collectively, the TIMSig could be a potential tool for risk-stratification, clinical decision making, treatment planning, and oncology immunotherapeutic drug development.

4.
Molecules ; 27(15)2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35897969

RESUMO

In order to explore a rapid identification method for the anti-counterfeit of commercial high value collections, a three-step infrared spectrum method was used for the pterocarpus collection identification to confirm whether a commercial pterocarpus bracelet (PB) was made from the precious species of Pterocarpus santalinus (P. santalinus). In the first step, undertaken by Fourier transform infrared spectroscopy (FTIR) spectrum, the absorption peaks intensity of PB was slightly higher than that of P. santalinus only at 1594 cm-1, 1205 cm-1, 1155 cm-1 and 836 cm-1. In the next step of second derivative IR spectra (SDIR), the FTIR features of the tested samples were further amplified, and the peaks at 1600 cm-1, 1171 cm-1 and 1152 cm-1 become clearly defined in PB. Finally, by means of two-dimensional correlation infrared (2DIR) spectrum, it revealed that the response of holocellulose to thermal perturbation was stronger in P. santalinus than that in PB mainly at 977 cm-1, 1008 cm-1, 1100 cm-1, 1057 cm-1, 1190 cm-1 and 1214 cm-1, while the aromatic functional groups of PB were much more sensitive to the thermal perturbation than those of P. santalinus mainly at 1456 cm-1, 1467 cm-1, 1518 cm-1, 1558 cm-1, 1576 cm-1 and 1605 cm-1. In addition, fluorescence microscopy was used to verify the effectiveness of the above method for wood identification and the results showed good consistency. This study demonstrated that the three-step IR method could provide a rapid and effective way for the anti-counterfeit of pterocarpus collections.


Assuntos
Pterocarpus , Pterocarpus/química , Espectrofotometria Infravermelho , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Madeira
5.
Int J Biol Macromol ; 209(Pt B): 1922-1932, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35500768

RESUMO

Water pollution by heavy metal ions is a global concern due to detrimental effects on the ecological environment and human health. To solve the problem of the stability and recyclability of the traditional adsorbents, we proposed three-dimensional lamellar porous cellulose nanofiber/polyacrylamide composite aerogel with outstanding pollutants adsorption, easy regeneration, and multiple recycling. The aerogel adsorbent was prepared by a two-step method via facile in-situ physical/chemical double cross-linking and freeze-drying processes. The resulting aerogels showed good thermal stability, superior water stability and excellent adsorption properties, with a maximum Langmuir adsorption capacity for Cu(II) ions up to 240 mg g-1 due to the in-situ physical/chemical combination of anionic polyacrylamide and carbonylated cellulose nanofibers. The adsorption mechanism was the electrostatic attraction, chelating effect and complex formation driving forces for the fast and efficient adsorption of Cu(II) ions. The removal efficiency of the aerogels for Cu(II) remained above 80% after 10 adsorption/regeneration cycles, suggesting its outstanding recyclability. The proposed aerogel adsorbent shows noteworthy potential for the practical treatment of heavy metal ion wastewater.


Assuntos
Metais Pesados , Nanofibras , Poluentes Químicos da Água , Resinas Acrílicas , Adsorção , Celulose/química , Humanos , Íons , Nanofibras/química , Poluentes Químicos da Água/análise
6.
Front Mol Biosci ; 8: 759173, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34901153

RESUMO

Long non-coding RNAs (lncRNAs), which were implicated in many pathophysiological processes including cancer, were frequently dysregulated in hepatocellular carcinoma (HCC). Studies have demonstrated that ferroptosis and immunity can regulate the biological behaviors of tumors. Therefore, biomarkers that combined ferroptosis, immunity, and lncRNA can be a promising candidate bioindicator in clinical therapy of cancers. Many bioinformatics methods, including Pearson correlation analysis, univariate Cox proportional hazard regression analysis, least absolute shrinkage and selection operator (LASSO) analysis, and multivariate Cox proportional hazard regression analysis were applied to develop a prognostic risk signature of immune- and ferroptosis-related lncRNA (IFLSig). Finally, eight immune- and ferroptosis-related lncRNAs (IFLncRNA) were identified to develop and IFLSig of HCC patients. We found the prognosis of patients with high IFLSig will be worse, while the prognosis of patients with low IFLSig will be better. The results provide an efficient method of uniting critical clinical information with immunological characteristics, enabling estimation of the overall survival (OS). Such an integrative prognostic model with high predictive power would have a notable impact and utility in prognosis prediction and individualized treatment strategies.

7.
ACS Omega ; 6(8): 5945-5952, 2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33681632

RESUMO

Since traditional methods for removing volatile organic compounds (VOCs) from wood consume large amounts of energy and generate environmental pollution, it is desired to develop a convenient and green treatment method. Oxidation by microwave-activated persulfate (MW-PS) is a promising alternative method that has been used to eliminate VOCs from wood. The penetration of microwave energy can destroy the wood pit membranes and increase VOC emissions. The VOCs are further degraded by ·OH and SO4 •-, which are generated via the activation of microwaves. This phenomenon can be detected by the electron paramagnetic resonance spectrometry. The 35 types of main VOCs of natural wood were determined, including alkanes/terpenes, alcohols/ethers, esters, aldehydes/ketones, and others. In the MW-PS system, 23 compounds were removed with an efficiency of 100%. Specifically, as one of the major compounds, the content of alkanes/terpenes was sharply decreased, and no alcohols/ethers and esters were detected. It was found that the optimal conditions of the MW-PS system for the minimum release of VOCs from wood were the microwave power of 462 W, irradiation time of 30 min, and PS dosage of 0.5 mmol/L.

8.
Artigo em Inglês | MEDLINE | ID: mdl-33572995

RESUMO

China has grown into the world's largest tourist source market and its huge tourism activities and resulting greenhouse gas (GHG) emissions are particularly becoming a concern in the context of global climate warming. To depict the trajectory of carbon emissions, a long-range energy alternatives planning system (LEAP)-Tourist model, consisting of two scenarios and four sub-scenarios, was established for observing and predicting tourism greenhouse gas peaks in China from 2017 to 2040. The results indicate that GHG emissions will peak at 1048.01 million-ton CO2 equivalent (Mt CO2e) in 2033 under the integrated (INT) scenario. Compared with the business as usual (BAU) scenario, INT will save energy by 24.21% in 2040 and reduce energy intensity from 0.4979 tons of CO2 equivalent/104 yuan (TCO2e/104 yuan) to 0.3761 Tce/104 yuan. Although the INT scenario has achieved promising effects of energy saving and carbon reduction, the peak year 2033 in the tourist industry is still later than China's expected peak year of 2030. This is due to the growth potential and moderate carbon control measures in the tourist industry. Thus, in order to keep the tourist industry in synchronization with China's peak goals, more stringent measures are needed, e.g., the promotion of clean fuel shuttle buses, the encouragement of low carbon tours, the cancelation of disposable toiletries and the recycling of garbage resources. The results of this simulation study will help set GHG emission peak targets in the tourist industry and formulate a low carbon roadmap to guide carbon reduction actions in the field of GHG emissions with greater certainty.


Assuntos
Gases de Efeito Estufa , Carbono , Dióxido de Carbono , China , Efeito Estufa , Indústrias
9.
Polymers (Basel) ; 12(3)2020 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-32210060

RESUMO

Stretching has a significant effect on the microstructure and ultimate performance of semi-crystalline polymers. To investigate the effect of stretching on structure and mechanical properties of uniaxial stretched PA612/SiO2, PA612 and PA612/SiO2 films were prepared at four temperatures close to the glass transition temperature at various strain. The samples were characterized by a transmission electron microscope (TEM), wide-angle X-ray diffractometer (WAXD), Two-dimensional wide-angle X-ray Scattering (2D-WAXS), differential scanning calorimeter (DSC), dynamic mechanical analyzer (DMA), and stretching tests. The results showed that the α phase was the dominant phase in PA612 casting film, no obvious γ phase was observed, while both stretching and the presence of SiO2 can induce the generation of α phase and improve the crystallinity of PA612. Crystals were oriented along the stretching direction and the b axis was parallel to the equatorial direction after stretching. The interplanar spacing of (010/110) decreased with the increasing stretching temperature and expanded with the increasing strain, while stretching temperature and strain present negligible effect on the interplanar spacing of (100). The grain size increased with the stretching temperature while decreased with strain. The presence of SiO2 led to reduce the yield stress and the stress drop beyond yielding of the composite. Uniaxial stretching gave rise to a significant improvement in the fracture stress and the glass transition temperature.

10.
Molecules ; 25(3)2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31979158

RESUMO

Volatile organic compounds (VOCs) in wood furniture are an important factor that affects indoor air quality. In this study, radiata pine (Pinus radiata D. Don) was treated with sodium bicarbonate and ozone aqueous solution to reduce the VOC contents without sacrificing mechanical properties. The VOCs of radiata pine were identified by gas chromatography-mass spectrometry (GC-MS), and the functional group changes of wood samples were characterized by Fourier-transform infrared spectroscopy (FTIR). The results showed that the main VOCs of radiata pine include alkenes, aldehydes, and esters. The sodium bicarbonate and ozone treatments almost eliminated the VOC contents of radiata pine. The two treatments mentioned above had little effect on compressive strength and surface color of radiata pine.


Assuntos
Ozônio/química , Pinus/química , Bicarbonato de Sódio/química , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Infravermelho com Transformada de Fourier
11.
Polymers (Basel) ; 11(6)2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31163610

RESUMO

Soybean meal-based adhesives are attractive potential environmentally friendly replacements for formaldehyde-based adhesives. However, the low strength and poor water resistance of soybean meal-based adhesives limit their practical application. This study was conducted to develop a natural fiber-reinforced soybean meal-based adhesive with enhanced water resistance and bonding strength. Pulp fiber (PF), poplar wood fiber (WF), and bagasse fiber (BF) were added as fillers into the soybean meal-based adhesive to enhance its performance via hydrogen bonding between the PF and the soybean meal system. The enhanced adhesive exhibited a strong crosslinking structure characterized by multi-interfacial interactions wherein PF served as a bridging ligament and released residual stress into the crosslinking network. The crosslinked structure and improved interfacial interactions were confirmed by Fourier transform infrared (FTIR) spectrophotometry, thermogravimetric analysis (TGA), and scanning electron microscopy (SEM) measurements. Plywood bonded with 4 wt % PF-containing soybean meal-based adhesive exhibited a wet shear strength (1.14 MPa) exceeding that of plywood bonded with the control group by 75.4% due to the stable crosslinking network having efficiently transformed stress and prevented the permeation of water molecules.

12.
Polymers (Basel) ; 11(2)2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30960188

RESUMO

In this study, poly(lactic acid) (PLA)/wood flour (WF) composites were prepared by first blending PLA with organo-montmorillonite (OMMT) at different contents (0.5, 1, 1.5, and 2 wt %). The physical and mechanical properties of the virgin and OMMT modified PLA and its WF composites were tested. The results showed that: (1) at low OMMT content (<1 wt %), OMMT can uniformly disperse into the PLA matrix with highly exfoliated structures. When the content increased to 1.5 wt %, some aggregations occurred; (2) after a second extruding process, the aggregated OMMT redistributed into PLA and part of OMMT even penetrated into the WF cell wall. However, at the highest OMMT content (2 wt %), aggregates still existed; (3) the highly exfoliated OMMT was beneficial to the physical and mechanical properties of PLA and the WF composites. The optimal group of OMMT-modified PLA was found at an OMMT content of 0.5 wt %, while for the PLA/WF system, the best properties were achieved at an OMMT content of 1.5 wt %.

13.
Carbohydr Polym ; 205: 72-82, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30446150

RESUMO

The exploitation of an efficient strategy for preparing flexible green conductive composites with an interconnected filler network is of great scientific and technical interest. Herein, a high-performance interconnected cellulose nanofiber (CNF) template functionalized tannic acid (TA)/polypyrrole (PPy) nanohybrid network (TPy@CNF) is fabricated by a green mussel-inspired co-modification approach. The network offers high electrical conductivity to prepare flexible, plant-derived soy protein isolate (SPI) composites. The mussel-inspired interface design demonstrates versatile functions of a reactive adhesion layer to construct a multiple-bond-regulated interconnected TPy@CNF conductive polymer network architecture without the need for harsh conditions and toxic reagents. This well-defined conducting TA/PPy-encapsulated CNF network is of great benefit in achieving strong synergistic interactions by enhancing electrical conductivity, reducing junction contact resistance, and ensuring efficient load transfer during bending. When integrating 7.5 wt% TPy@CNF, the prepared SPI composites deliver significantly enhanced conductivity of 0.078 S m-1 along with superior mechanical robustness (improved tensile strength and toughness) and excellent structural stability. This interconnected network design strategy can provide a green yet feasible approach for elaborate construction of CNF/conducting polymers in advanced energy-storage technologies.

14.
Artigo em Inglês | MEDLINE | ID: mdl-30453680

RESUMO

As the main material in indoor furniture, southern yellow pine (Pinus spp.) releases volatile organic compounds (VOCs) into the environment during use. To better understand variations in the contents of VOCs in southern yellow pine before and after heat treatment, this study conducts dry heat treatment on southern yellow pine at 140 °C and 220 °C. Headspace solid phase micro-extraction was used to extract VOCs from southern yellow pine. The VOCs of southern yellow pine before and after heat treatment were identified via gas chromatography-mass spectrometry, and chemical component differences were characterized via Fourier transform infrared spectroscopy. Results reveal 86 VOCs in pure southern yellow pine, including alcohols, aromatics, acids, aldehydes, alkanes, alkenes, and some trace compounds (e.g., furans, ketones, phenols, and esters). With an increase in heat-treatment temperature, the contents of alkanes increased, whereas those of alcohols and alkenes decreased. The contents of aromatics, acids, and aldehydes were highest when heat treated at 140 °C. At 220 °C, the total contents of key VOCs in southern yellow pine were lowest.


Assuntos
Monitoramento Ambiental/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Temperatura Alta , Pinus/química , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/química , Decoração de Interiores e Mobiliário
15.
Molecules ; 23(9)2018 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-30154322

RESUMO

Dalbergia cultrate, Dalbergia latifolia, and Dalbergia melanoxylon are precious and valuable traded timber species of the genus Dalbergia. For chemotaxonomical discrimination between these easily confused species, the total extractive content of the three wood species was determined using four different organic solvents. Fourier transform infrared (FTIR) spectroscopy was used to analyze functional group differences in the extractive components, inferring the types of principal chemical components according to characteristic peak positions, intensities, and shapes. Gas chromatography-mass spectrometry (GC-MS) was carried out a detailed characterization of the extractive components. The relative content of individual chemical components was determined by area normalization. Results revealed differences in the chemical components and total and individual extract contents of the three Dalbergia species, indicating that FTIR and GC-MS spectroscopy can be applied to identify and discriminate between Dalbergia cultrate, Dalbergia latifolia, and Dalbergiamelanoxylon.


Assuntos
Dalbergia/química , Extratos Vegetais/análise , Extratos Vegetais/química , Cromatografia Gasosa-Espectrometria de Massas , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/química , Extratos Vegetais/isolamento & purificação , Espectroscopia de Infravermelho com Transformada de Fourier , Madeira/química
16.
Molecules ; 23(1)2018 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-29346285

RESUMO

Indoor air quality problems are usually revealed by occupants' complaints. In this study, the odors of two types of hardwood species, namely, Cathy poplar (Populus cathayana Rehd.) and rubberwood (Hevea brasiliensis) were selected and extracted with ethanol-toluene for removal of extractives in an attempt to eliminate the odors. The odorous components of neat and extracted woods were identified by gas chromatography-mass spectrometry/olfactometry (GC-MS/O). The results showed that about 33 kinds of key volatile compounds (peak area above 0.2%) were detected from the GC-MS, and about 40 kinds of odorants were identified from GC-O. The components were concentrated between 15 and 33 min in GC-O, which was different from the concentration time in GC-MS. Lots of the odors identified from GC-O were unpleasant to humans, and variously described as stinky, burnt, leather, bug, herb, etc. These odors may originate from the thermos-oxidation of wood components. After extraction, the amounts and intensities of some odorants decreased, while some remained. However, the extraction process resulted in a benzene residue and led to increased benzene odor.


Assuntos
Poluição do Ar em Ambientes Fechados , Cromatografia Gasosa , Odorantes/análise , Olfatometria , Madeira/química , Compostos Orgânicos Voláteis/análise
17.
ACS Omega ; 3(9): 10657-10667, 2018 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31459186

RESUMO

The development of micro- and nanofibril cellulose to improve strength while reducing the side effects of toughness and water resistance can benefit integrated polymer performance. Inspired by the interior microstructure of mussel byssus, this paper proposed an efficient means of generating an active block microfibrillated cellulose/polyurethane elastomer using an epoxy monomer as a pre-crosslinked agent with the addition of a poly(dopamine) layer. The block elastomer served as a multifunctional crosslinker, constructing a covalent network and interfacial hydrogen bonding that interlinked the elastomer with a soy protein isolate (SPI) matrix. Compared with the pristine SPI film, the introduction of the block elastomer induced remarkable improvements in tensile strength and toughness (146.7 and 102.1%, respectively). Additionally, the block elastomer was employed to further estimate its reinforcing effect in SPI resin modification, which also exhibited favorable water resistance and adhesion performance. This strategy may provide a new approach for constructing superior elastomers to reinforce applicable biomass composites.

18.
Nat Prod Res ; 32(13): 1518-1524, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29022760

RESUMO

A new germacrenolide (1) and fourteen known terpenoids (2-15) were isolated from the barks of Magnolia maudiae (Dunn) Figlar (Magnoliaceae). The structure of (7αH,11ßH)-2α,8α-dihydroxy-4α,5ß-epoxy-germacr-1(10)-en-6α,12-olide (1) was elucidated by physical and spectroscopic data analysis, including 1D, 2D NMR and HR-ESI-MS. Lyratol F (9) was isolated from Magnolia for the first time. The structures of known compounds were established by comparing their spectroscopic data with those in literatures.


Assuntos
Magnolia/química , Terpenos/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Casca de Planta/química , Espectrometria de Massas por Ionização por Electrospray
19.
Materials (Basel) ; 10(7)2017 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-28773191

RESUMO

Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) has been an important afforestation species in northeast China. It has obvious defects of buckling and cracking easily, which are caused by its chemical components. Trametes versicolor (L.) Lloyd, a white-rot fungus, can decompose the cellulose, hemicellulose, and lignin in the wood. White-rot fungus was used to biologically degrade Chinese fir wood. The effects of different degradation time on the Chinese fir wood's mechanical properties, micromorphology, chemical components, and crystallinity were studied. The results showed that the heartwood of Chinese fir was more durable than the sapwood and the durability class of Chinese fir was III. Trametes versicolor (L.) Lloyd had a greater influence on the mechanical properties (especially with respect to the modulus of elasticity (MOE)) for the sapwood. Trametes versicolor (L.) Lloyd degraded Chinese fir and colonized the lumen of various wood cell types in Chinese fir, penetrated cell walls via pits, caused erosion troughs and bore holes, and removed all cell layers. The ability of white-rot fungus to change the chemical composition mass fraction for Chinese fir was: hemicellulose > lignin > cellulose. The durability of the chemical compositions was: lignin > cellulose > hemicellulose. The crystallinity of the cellulose decreased and the mean size of the ordered (crystalline) domains increased after being treated by white-rot fungus.

20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(9): 2377-81, 2012 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-23240400

RESUMO

In the present article, near infrared spectra of 89 wood samples of different geographical provenances and species were measured, and back propagation artificial neural networks(BPANN) and generalized regression neural network (GRNN) were used for modeling of wood species NIRS identifying. Parameters for two neural networks were chosen via analysis of variance, respectively; and networks were trained with optimum parameters. Considering the difference between spectra, spectra with different levels of white noise and different levels of bias were simulated and predicted by using the models built. It was found that both the two models had satisfactory prediction results, identification correct rates obtained by BPANN model applied to spectra with bias level no higher than 2% and noise level no higher than 4% were above 97%; correct rates obtained by GRNN model applied to spectra with bias level no higher than 2% and noise level no higher than 4% were above 99%.


Assuntos
Espectroscopia de Luz Próxima ao Infravermelho , Madeira/classificação , Modelos Teóricos , Redes Neurais de Computação
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