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1.
J Environ Manage ; 304: 114306, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34923416

RESUMO

Compared with phytoextraction, growing suitable crops may be a more profitable and practical approach for managing contaminated farmland, especially when there are multiple pollutants. In this 5-year field study, the phytoaccumulator Hylotelephium spectabile, the high-biomass species amaranth (Amaranthus hypochondriacus), and a winter rapeseed/maize rotation crop were cultivated on farmland contaminated with cadmium (Cd) and lead (Pb). Over 4 consecutive years, the annual Cd uptake and extraction efficiency of H. spectabile was 117.6 g hm-2 and 2.36%, respectively. The Cd extraction efficiency of amaranth was equivalent to that of H. spectabile because of its high biomass, and it extracted more Pb (660-2210 g hm-2) from the soil than did H. spectabile. However, neither of these species was able to remediate contaminated farmland rapidly and inexpensively, even with enhancing strategies such as variety screening and the addition of fertilizers and a chelating agent. A safe utilization approach to cultivate rapeseed instead of wheat significantly reduced the carcinogenic and noncarcinogenic risks. The concentrations of heavy metals in rapeseed oil were below the limits specified in the Chinese national food standard, and the heavy metal concentrations in the byproducts (rapeseed meal and straw) were below the limits specified in Chinese national standards for organic fertilizer and feed. The cost of safe utilization was one-quarter that of phytoextraction, and the net economic benefit was 33.5%-123.5% higher than that of wheat crops. Therefore, the rapeseed/maize rotation is a profitable and feasible approach for the safe utilization of Cd- and Pb-contaminated farmland on the northern plains of China.


Assuntos
Brassica napus , Metais Pesados , Poluentes do Solo , Biodegradação Ambiental , Cádmio/análise , Fazendas , Chumbo , Metais Pesados/análise , Solo , Poluentes do Solo/análise , Zea mays
2.
Bull Environ Contam Toxicol ; 109(6): 1081-1087, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36271926

RESUMO

Field experiments were conducted to investigate the effects of two foliar fertilizers, water-soluble chitosan (WSC) and Na2SiO3 (Si), on the accumulation of Pb by a low-Pb accumulator Brassica napus cultivar (QY-1) grown at two mildly Pb-contaminated farmland sites surrounding working smelters in Jiyuan city, Henan province, China. Regardless of the frequency of the fertilizer treatments, the foliar application of WSC (0.01%) or Si (0.15%) significantly increased the QY-1 biomass and decreased the grain Pb concentrations. Compared with the control treatment, spraying plants once with WSC or Si during the flowering period achieved the best effect in the two soils with different pollution, which may be because inhibiting the accumulation of Pb in grains by decreasing the husk-to-grain transfer coefficient. Thus, the foliar application of WSC or Si combined with the cultivation of a low-Pb accumulator is a promising approach for optimizing the utility of Pb-contaminated farmland affected by atmospheric deposition.


Assuntos
Brassica napus , Quitosana , Poluentes do Solo , Fertilizantes , Poluentes do Solo/análise , Chumbo , Fazendas , Água , Solo , Grão Comestível/química , Cádmio/análise
3.
Bull Environ Contam Toxicol ; 107(6): 1128-1135, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34159411

RESUMO

A pot experiment was conducted to investigate the effects of 0.5% and 1% alkaline, clay mineral and phosphorus amendments, as well as 2% and 5% organic amendments, on lead (Pb) soil bioavailability and Pb absorption by the low-Pb accumulator kumquat (Citrus japonica Thunb.) 'Cuipi' in two typical Pb-contaminated soils, Jiyuan and Yangshuo, from northern and southern China, respectively. The diethylenetriaminepentaacetic acid-extractable Pb soil concentration and Pb accumulation in kumquat significantly decreased with amendment additions. High amendment doses had greater inhibitory effects than low doses but no significant effects on the kumquat's biomass in the two typical soils. Alkaline, but not clay mineral, amendments greatly increased the soil pH level. Organic amendments effectively reduced Pb accumulation owing to their strong adsorptive capacities. Thus, using organic amendments combined with a low-Pb accumulator kumquat forms a suitable farming practice for producing safe fruit in the two common types of Pb-contaminated soils in China.


Assuntos
Rutaceae , Poluentes do Solo , Disponibilidade Biológica , Frutas/química , Chumbo , Solo , Poluentes do Solo/análise
4.
Cell Mol Neurobiol ; 37(1): 17-28, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26971525

RESUMO

Silent information regulator factor 2-related enzyme 1 (sirtuin 1, Sirt1) is a nicotinamide adenine dinucleotide-dependent deacetylase, which can deacetylate histone and non-histone proteins and other transcription factors, and is involved in the regulation of many physiological functions, including cell senescence, gene transcription, energy balance, and oxidative stress. Ischemia/hypoxia injury remains an unresolved and complicated situation in the diseases of ischemia stroke, heart failure, and coronary heart disease, especially among the old folks. Studies have demonstrated that aging could enhance the vulnerability of brain, heart, lung, liver, and kidney to ischemia/hypoxia injury and the susceptibility in old folks to ischemia/hypoxia injury might be associated with Sirt1. In this review, we mainly summarize the role of Sirt1 in modulating pathways against energy depletion and its involvement in oxidative stress, apoptosis, and inflammation under the condition of ischemia/hypoxia.


Assuntos
Hipóxia/metabolismo , Isquemia/metabolismo , Sirtuína 1/fisiologia , Animais , Metabolismo Energético/fisiologia , Humanos , Estresse Oxidativo/fisiologia , Transdução de Sinais/fisiologia
5.
Chemosphere ; 319: 138019, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36736483

RESUMO

The influence of environmental factors on Cd accumulation by Hylotelephium spectabile and its physiological mechanisms are unclear. A field trial was conducted to investigate the effects of nitrogen, soil moisture, and light regulation on plant growth, Cd absorption and translocation, and the photosynthetic characteristics of two H. spectabile populations (LN with high Cd accumulation capacity and HB1 with relatively low Cd accumulation capacity). The results showed that Cd accumulation in LN was 59.6% higher than that in HB1 which may partly be explained by the inherent high transpiration rate of LN, especially at the terminal stage. In addition, the photosynthetic rate of LN responded more positively to nitrogen than HB1, which further amplified its advantages on plant growth and Cd accumulation. Moderate drought significantly stimulated root growth of LN, indicating that LN possesses stronger resistance to drought. Shade inhibited Cd distribution, rather than directly affecting Cd concentrations in H. spectabile. The combined stress of shade and drought had a synergistic effect on Cd translocation in H. spectabile. Moreover, LN achieved 17.3%∼444.5% higher transpiration levels than HB1 under environmental stress, which ensured a more efficient Cd transport capacity of LN. Therefore, the investigation of photosynthetic characteristics further revealed the physiological mechanism by which LN accumulated Cd superior to HB1 under environmental stress and responded more positively to nitrogen nutrition.


Assuntos
Cádmio , Poluentes do Solo , Cádmio/análise , Nitrogênio/farmacologia , Biodegradação Ambiental , Poluentes do Solo/análise , Fotossíntese , Solo , Raízes de Plantas/química
6.
Sci Total Environ ; 879: 163034, 2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-36990239

RESUMO

Intercropping the arsenic (As) hyperaccumulator Pteris vittata with fruit trees can safely yield peaches in As-polluted orchards in South China. However, the soil As remediation effects and the related mechanisms of P. vittata intercropped with peach trees with additives in the north temperate zone have rarely been reported. A field experiment was conducted to systematically study the intercropping of peach (Amygdalus persica) with P. vittata with three additives [calcium magnesium phosphate (CMP), ammonium dihydrogen phosphate (ADP), and Stevia rebaudiana Bertoni residue (SR)] in a typical As-contaminated peach orchard surrounding a historical gold mine in Pinggu County, Beijing City. The results showed that compared with monoculture (PM) and intercropping without addition (LP), the remediation efficiency of P. vittata intercropping was significantly increased by 100.9 % (CMP) to 293.5 % (ADP). CMP and ADP mainly compete with available As (A-As) adsorbed to the surface of Fe-Al oxide through PO43-, while SR might activate A-As by enhancing dissolved organic carbon (DOC) in P. vittata rhizospheres. The photosynthetic rates (Gs) of intercropped P. vittata were significantly positively correlated with pinna As. The intercropping mode applied with the three additives did not obviously affect fruit quality, and the net profit of the intercropping mode (ADP) reached 415,800 yuan·ha-1·a-1. The As content in peaches was lower than the national standard in the intercropping systems. Comprehensive analysis showed that A. persica intercropped with P. vittata applied with ADP is better than other treatments in improving risk reduction and agricultural sustainability. In this study, a theoretical and practical basis is provided for the safe utilization and remediation of As-contaminated orchard soil in the north temperate zone.


Assuntos
Arsênio , Pteris , Poluentes do Solo , Arsênio/análise , Pteris/química , Biodegradação Ambiental , Poluentes do Solo/análise , Solo/química
7.
Huan Jing Ke Xue ; 43(9): 4779-4790, 2022 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-36096618

RESUMO

In order to explore the distribution characteristics of heavy metal contamination of farmland soil surrounding Luancheng town, Shijiazhuang City, Henan province, the concentrations of As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn in the surface soil and crops were determined and assessed. The principal components were also analyzed for source apportionment. The heavy metal concentrations in crops were further detected, and the non-carcinogenic health risks in the study area were evaluated using the probabilistic risk assessment method, as to provide a theoretical basis for the treatment, prevention, and control of heavy metal pollution in farmland soil in Luancheng. According to the results, ω(Cd), ω(Cr), ω(Cu), ω(Pb), and ω(Zn) in the soils were 0.06-1.08, 22.14-473.47, 12.83-150.74, 10.75-577.72, and 62.23-652.78 mg·kg-1, which exceeded the standard with over-standard rates reaching 1.83%, 1.22%, 0.61%, 0.61%, and 1.22%, respectively. Further, Cd and Pb were transported into crops, in which Cd concentrations exceeded the standard in some corn samples, and Cd and Pb concentrations exceeded the standard in some wheat samples. The total non-carcinogenic health risks (TTHQ) to the human body caused by the consumption of heavy metals in corn grown in the study area were all less than 1, with no obvious negative effects, and TTHQ was higher than 1 in wheat, increasing the likelihood of negative impacts on the human body. With the influence of the distribution of pollution-related enterprises in the industrial zone, heavy metal concentrations were higher in the south, west, and middle directions of the study area. Among them, the study area soil was slightly contaminated by Cd (Level 1). Cd and Hg had a slight potential ecological risk (Level 2), whereas other heavy metals had low potential ecological risk (Level 1). In general, most of the surface cultivated soil was not obviously polluted by heavy metals in the study area. According to the PMF results and survey, we speculated that soil heavy metals mainly came from soil parent material (52.05%), artificial pollution sources (historical sewage irrigation and industrial manufacture) (32.98%), and atmospheric deposition (14.97%). To summarize, the study area should be divided into a priority protection category and safe utilization category. The input of pollution sources should be strictly controlled for the priority protection category, and alternative planting, rotating, and fallow should be implemented for the safe utilization category to reduce the risk of standard-exceeding agricultural products.


Assuntos
Mercúrio , Metais Pesados , Poluentes do Solo , Cádmio , Produtos Agrícolas , Monitoramento Ambiental , Fazendas , Humanos , Chumbo , Metais Pesados/análise , Medição de Risco , Solo , Poluentes do Solo/análise
8.
Front Genet ; 12: 785839, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34976018

RESUMO

Background: Head and neck squamous cell carcinoma (HNSCC) is a malignant tumor, which makes the prognosis prediction challenging. Ferroptosis is an iron-dependent form of non-apoptotic regulated cell death, which could affect cancer development. However, the prognostic value of ferroptosis-related long non-coding RNA (lncRNA) in HNSCC is still limited. Methods: In the current study, we employed the DESeq2 method to characterize the differentially expressed ferroptosis-related genes (FEGs) between cancer and normal samples. Next, the FEG-related lncRNAs (FElncRNAs) were identified using Spearman's correlation analysis and multiple permutation hypotheses. Subsequently, LASSO and stepwise multivariate Cox regression analyses were undertaken to recognize the prognosis-related FElncRNA signature (PFLS) and risk scores. Results: Herein, we first identified 60 dysregulated FEGs and their co-expressed FElncRNAs in HNSCC. Then, we recognized a set of six FElncRNAs PFLS (SLCO4A1-AS1, C1RL-AS1, PCED1B-AS1, HOXB-AS3, MIR9-3HG, and SFTA1P) for predicting patients' prognostic risks and survival outcomes. We also assessed the efficiency of PFLS in the test set and an external validation cohort. Further parsing of the tumor immune microenvironment showed the PFLS was closely associated with immune cell infiltration abundances. Notably, the low-risk group of the PFLS showed a higher MHC score and cytolytic activity (CYT) score than the high-risk group, implying the low-risk group may have greater tumor surveillance and killing ability. In addition, we observed that the expression levels of two immune checkpoints (ICPs), i.e., programmed cell death protein 1 (PD-1) and programmed cell death 1 ligand 1 (PD-L1), showed significant associations with patients' risk score, prompting the role of the PFLS in ICP blockade therapy. Finally, we also constructed a drug-PFLS network to reinforce the clinical utilities of the PFLS. Conclusion: In summary, our study indicated that FElncRNAs played an important role in HNSCC survival prediction. Identification of PFLS will contribute to the development of novel anticancer therapeutic strategies.

9.
Huan Jing Ke Xue ; 42(2): 900-908, 2021 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-33742885

RESUMO

In order to fully explore the spatial distribution of soil heavy metal contaminants in farmland soil surrounding a typical industrial area in Dakuai town, Xinxiang city, Henan Province, the concentrations of As, Cd, Cr, Cu, Ni, Pb, and Zn in the surface soil and within the soil profile were determined and assessed. The principal components were also analyzed for source apportionment to provide a theoretical basis for the control and prevention of heavy metal pollution. According to the results, the soils in the study area are severely contaminated by Cd and Cu and moderated contaminated by As due to the battery manufacture and Cu (e.g., pipe and wire) processing. The concentrations of Cd, Cu, and As in soils were (2.56±1.23) mg·kg-1, (205.58±157.49) mg·kg-1, and (15.27±4.14) mg·kg-1, respectively, which exceeds standards by 100%, 89.44%, and 3.40%, respectively. Accounting for the influence of pollution sources, terrain, runoff erosion, and prevailing wind direction, all heavy metal concentrations were higher in the south direction, lower in the north direction. The concentrations of Cd and Cu in soil profile samples decreased with depth, with highest concentrations at the surface, indicating the strong effect of industrial activities. Arsenic concentrations varied little with soil depth due to its strong migration ability in alkaline soil, again suggesting an industrial source. Among them, the soil of study area was severely contaminated by Cd and Cu (Level 5). Cd poses a severe potential ecological risk (Level 5) and Cu poses a medium risk (Level 2) in the study soils, while other heavy metals show low potential ecological risk (Level 1). The order of the risk identified was Cd > Cu > Ni > As > Pb > Cr > Zn. In addition, the combined potential ecological risk of heavy metals in the target area is severe. The principal component analysis showed that the high As, Cd, and Cu contents are mainly derived from industrial areas. Therefore, it is urgent to remediate Cd and Cu soil contamination in this area and implement precautions to limit As contamination.


Assuntos
Metais Pesados , Poluentes do Solo , China , Cidades , Monitoramento Ambiental , Fazendas , Metais Pesados/análise , Medição de Risco , Solo , Poluentes do Solo/análise
10.
Huan Jing Ke Xue ; 42(3): 1177-1184, 2021 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-33742914

RESUMO

A pot experiment was conducted to investigate the growth response and Cd accumulation characteristics among different populations of Hylotelephium spectabile in Cd-contaminated cinnamon soil (2.22 mg·kg-1) with the addition of different concentrations of NaCl. Results showed that the biomasses and Cd concentrations of H. spectabile showed significant differences among different populations under Cd alone or Cd-salt combined stress. Moreover, salt stress aggravated the growth inhibition of H. spectabile and the Cd concentrations in different H. spectabile populations showed a declining trend, which may be related to the salt-derived pH increase leading to a decrease in Cd bioavailability. In addition, the growth and Cd absorption responses of H. spectabile under salt stress were significantly different in the different populations. The shoot biomasses of the LN population were significantly higher than in other populations under different treatment, and showed no significant decrease with the addition of 1% NaCl when compared with the control treatment and the tolerance index remained 0.91. At the same time, the shoot Cd concentration of the LN population was significantly higher than in other populations under different treatments. The result may be attributed to the Cd accumulation and detoxification mechanisms in LN are prior than other populations that may also have important physiological mechanisms for tolerance of salt stress. In summary, although Cd uptake in H. spectabile decreased with salt stress, there were significant differences among different populations. LN populations accumulated 84.4 µg·plant-1 Cd in shoots with 2% NaCl addition, which was 48.4%-89.3% higher than in other populations. Therefore, H. spectabile, especially LN populations, is a good candidate for phytoremediation of Cd-contaminated saline soil.


Assuntos
Cádmio , Poluentes do Solo , Biodegradação Ambiental , Cádmio/toxicidade , Raízes de Plantas , Estresse Salino , Poluentes do Solo/toxicidade
11.
Carbohydr Polym ; 246: 116559, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32747239

RESUMO

Water-soluble chitosan (WSC) was used to enhance cadmium (Cd) phytoextraction by Hylotelephium spectabile, a promising accumulator. The effect of WSC on Cd forms and functional groups in contaminated soils was determined to clarify the internal mechanism of WSC affecting phytoremediation. Results showed that WSC significantly increased the water-soluble and acid-extractable Cd in contaminated soils by 20.3 %-143.5 % and 2.4 %-39.5 %, respectively. Fourier transform infrared spectra analysis showed that amino and hydroxyl groups in soils were significantly increased in the presence of WSC. The coordination of Cd with increased amino and hydroxyl groups may play important roles in formation of Cd complexes and mobilizing Cd in soils. WSC significantly increased the Cd phytoextraction of H. spectabile by 56.1 %-115.7 % without obvious growth inhibition, which was further confirmed under field trial conditions. Therefore, it is feasible to apply WSC as a soil amendment to Cd-contaminated soils during remediation with H. spectabile.


Assuntos
Cádmio/metabolismo , Quitosana/química , Quitosana/farmacologia , Crassulaceae/metabolismo , Poluentes do Solo/metabolismo , Solo/química , Água/química , Biodegradação Ambiental/efeitos dos fármacos , Quitosana/metabolismo , Radical Hidroxila/metabolismo , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
12.
Environ Sci Pollut Res Int ; 27(17): 21364-21375, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32277416

RESUMO

The interactions between Cd and Zn in their effects on plants are inconsistent and difficult to predict. A hydroponic experiment was conducted to investigate the effects of Cd and Zn and their interactions on root morphology and metal translocation in two populations of Hylotelephium spectabile (Boreau) H. Ohba (Crassulaceae, HB1 and HB2). Both populations showed relative tolerance to high levels of Cd and Zn, except that the leaf biomass of HB1 significantly decreased by 44.6% with 5-mg/L Cd plus 10-mg/L Zn. Root growth was inhibited in both populations by addition of 20-mg/L Zn under Cd stress, while 10-mg/L Zn showed little impact on the root growth inhibition of HB2. Roots with diameter 0.1-0.4 mm contributed most of the total root length (RL) and root surface area (RSA) of H. spectabile. In both populations, these root parameters showed greater suppression with the combined stress of Cd plus Zn than under Cd or Zn single stress, except by adding 10-mg/L Zn under Cd stress. Moreover, HB2 maintained relatively higher RL and RSA than HB1 under the different treatments, which implied that HB2 might possess a more effective mechanism than HB1 for coping in response to Cd and Zn stress. The addition of Zn not only affected the absorption of Cd but also significantly affected the distribution of Cd in different tissues of H. spectabile. A low level of Zn led to increased Cd in the stem of HB2, but an increase in Cd in the leaf and root of HB1. Addition of 10-mg/L Zn led to a significant increase by 188% and 170% in Cd accumulation in aboveground part of HB2 under 2- and 5-mg/L Cd stress, whereas the addition of Zn had little effect on Cd accumulation in HB1. Thus, strong positive interactions of Cd and Zn occurred in HB2, which showed great potential for application in phytoremediation of soil contaminated with both Cd and Zn, warranting further investigation under field condition.


Assuntos
Crassulaceae , Poluentes do Solo , Biodegradação Ambiental , Cádmio , Raízes de Plantas , Zinco
13.
Huan Jing Ke Xue ; 41(9): 4226-4233, 2020 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124304

RESUMO

A field experiment with an orthogonally designed experiment L9(34) was designed to investigate the effect of different N, P, and K levels on plant growth and Cd uptake by Hylotelephium spectabile. The results showed that the biomass of H. spectabile significantly increased with the N application rate. The highest dry weight in the shoot occurred in the treatments with a high level of N (337.5 kg ·hm-2), which was 0.86-2.00 times higher than the value with no fertilizer treatment. The addition of K contributed to promoting the Cd absorption of H. spectabile, while no effect was observed when N and P were added. Consequently, NPK fertilizers contribute to increasing the Cd uptake of H. spectabile, and the N and K fertilizer play important role in plant growth and Cd absorption respectively. Moreover, the effect of fertilizers on Cd uptake of H. spectabile was in the order of N > K > P, which indicated that N fertilizer was the main factor for promoting the Cd phytoextraction efficiency of H. spectabile by increasing the biomass. Therefore, the application of high levels of N combined with moderate levels of P and K will be an effective approach to improve the Cd phytoremediation efficiency of H. spectabile by promoting its growth, and the Cd uptake can be increased by a factor of 0.9-2.2 compared to no fertilizer treatment condition.


Assuntos
Cádmio , Poluentes do Solo , Biodegradação Ambiental , Cádmio/análise , Fertilizantes/análise , Nitrogênio , Nutrientes , Solo , Poluentes do Solo/análise
14.
Zhongguo Zhong Yao Za Zhi ; 32(7): 630-2, 2007 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-17583209

RESUMO

OBJECTIVE: To develop an HPLC method for the determination of serum level of Crebanine (Cre) and study on the pharmacokinetics of Cre injection in rabbits. METHOD: To sample blood serum from the rabbits' ears which were injected the Cre by 2.0 mg x kg(-1) at different time and use HPLC to determine the concentration of Cre in it, the pharmacokinetic parameters were accessed by the DAS software. RESULT: Cre was fitted to a two compartment open pharmacokinetic model in rabbits. There was no signifiant difference between the male and female rabbits'pharmacokinetic by t-test. The mainly pharmacokinetic parameters were: t1/2alpha = (3. 246 +/-0.222) min, t1/2beta = (36.67+/-5.52) min, Cmax = (1.401 +/- 0.062) mg x L(-1), Vd = (5.928 +/- 0.877) L x kg(-1), Cl = (0. 051 +/-0.003) L x min(-1) x kg(-1). CONCLUSION: This experiment can objectively show the pharmacokinetics regularity of Crebanine injection in rabbits. Crebanine injection was a speeding disposition drug (t1/2 <1 h) and disposed extensively and rapidly in rabbits.


Assuntos
Aporfinas/farmacocinética , Plantas Medicinais/química , Stephania/química , Animais , Aporfinas/administração & dosagem , Aporfinas/sangue , Cromatografia Líquida de Alta Pressão , Feminino , Injeções , Masculino , Taxa de Depuração Metabólica , Coelhos
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