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1.
Opt Lett ; 48(21): 5595-5598, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37910711

RESUMO

A multi-core fiber (MCF) provides a compact solution for three-dimensional (3D) shape measurement. In this Letter, an incremental shape measurement method for 3D paths is proposed, using an MCF based on fiber Bragg gratings (FBGs). A few FBG sets can iteratively provide plenty of strain information about the 3D path during navigation. The overall continuities of the curvature and torsion are improved based on intensive strain calculations. Meanwhile, the transformation matrix algorithm is used to reconstruct the shape of 3D paths. Dynamic measurement experiments of a seven-core fiber with two FBG sets are carried out to verify the incremental shape measurement method. This method shows a great performance of the different paths, with a maximum incremental position error of 4.68%.

2.
Environ Sci Pollut Res Int ; 30(36): 85822-85834, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37393592

RESUMO

A novel composite (nZVI/HNTs) was prepared via incorporating nano zero-valent iron (nZVI) on halloysite nanotubes (HNTs) for degrading tetracycline hydrochloride (TCH) with existence of persulfate (PS). The adsorption process of nZVI/HNTs to TCH conformed to the Freundlich isotherm model and pseudo-second-order kinetic model, and its maximum adsorption capacity was 76.62 mg·g-1. Furthermore, the nZVI/HNTs + PS system exhibited satisfactory degradation efficiency (84.21%) for TCH, and stable nZVI/HNTs (Fe leaching < 0.001 mg·L-1) could be reused. When nZVI/HNTs dosage, PS dosage and temperature increased, TCH degradation could be enhanced. After four cycling, nZVI/HNTs + PS system had still 65.8% degradation for TCH. The quenching tests and EPR analysis evidenced that SO4•- was predominant instead of •OH in such system. Three possible pathways of TCH degradation were provided through the liquid chromatograph-mass spectrometer (LC-MS) determination. Meanwhile, the biological toxicity prediction analysis indicated that the nZVI/HNTs + PS system would be an environment friendly treatment method toward TCH pollution.


Assuntos
Nanotubos , Poluentes Químicos da Água , Tetraciclina/análise , Argila , Ferro/análise , Poluentes Químicos da Água/análise
3.
Environ Sci Pollut Res Int ; 29(39): 59317-59327, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35384541

RESUMO

Most studies have shown that improper disposal of e-waste can accelerate the release of high concentrations of polybrominated diphenyl ethers (PBDEs), and this situation causes environmental pollution and human health risks. The recycling technology of waste electronic plastics based on solvent processes can reduce environmental pollution and health risks from PBDEs. In this study, high impact polystyrene (HIPS) from waste TV sets was taken as the research object, and d-limonene and n-propanol were used as solvent and precipitant, respectively. We studied the relationship between the precipitation conditions and the size of precipitate particles, and the effect laws of precipitation conditions on the removal percentage of PBDEs were discussed. Transferring behavior of PBDEs during precipitation was investigated, and the parameters suitable for removing PBDEs from HIPS solution were confirmed. Results showed that lower HIPS concentration in d-limonene, lower precipitation temperature, higher mass ratio of n-propanol to HIPS solution, and greater stirring speed were conducive to form smaller and more uniform precipitate particles. All conditions (concentration, temperature, mass ratio, and stirring rate) that could increase the solubility of PBDEs in the mixed solvent of limonene and n-propanol or decrease the swelling degree of HIPS precipitate particles, or reduce the size of particles could improve the removal percentage of PBDEs. The investigated results indicated that insoluble PBDEs (e.g., decabromodiphenyl ether) transferred into the HIPS precipitate mainly through the generated crystals and then precipitated together with the HIPS particles, and soluble PBDEs (e.g., octabromodiphenyl ether) migrated into the precipitate by the solution entrained. The precipitate particles, which measured approximately 1.0 mm (on average), were obtained when the solution containing 10% of HIPS from waste TV shell was precipitated by adding n-propanol equivalent to twice the mass of the solution at 40 °C and 3000 r/min stirring speed. The total concentration of PBDEs in the precipitate particles (dried) was reduced to 2369 mg/kg, and 88.06% of the PBDEs in the original plastic solution was successfully removed by this process.


Assuntos
Resíduo Eletrônico , Éteres Difenil Halogenados , 1-Propanol , Resíduo Eletrônico/análise , Monitoramento Ambiental , Éteres Difenil Halogenados/análise , Humanos , Limoneno , Plásticos/química , Poliestirenos , Solventes
5.
Front Pharmacol ; 12: 658998, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34248622

RESUMO

Bazi Bushen capsule (BZBS), as a Chinese medicine used to relieve fatigue, has been proven effective for the treatment of atherogenesis through antilipid effects. To investigate the potential mechanism of BZBS in the anti-atherosclerotic effect, Ovx/ApoE-/- mice were applied to investigate the anti-atherosclerotic efficiency and potential mechanism of BZBS. Therapeutic effect was evaluated based on the number of CD68+ and CD3+ cells, the level of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), and the ratio of cleaved caspase-3/caspase-3, as well as increasing ratio of Bcl2/Bax. Human umbilical vein endothelial cells (HUVECs) were chosen to evaluate the role of GPER1. Treatment with BZBS reduced lipid deposition by reducing the numbers of CD68+ and CD3+ cells, the level of ICAM-1 and VCAM-1, and the ratio of cleaved caspase-3/caspase-3, and increasing the ratio of Bcl2/Bax as compared with the control group. In si-GPER1-treated HUVECs, the anti-apoptotic effect of BZBS was decreased. This study revealed that BZBS exhibited a clear effect against atherogenesis via GPER1-dependent anti-inflammatory and anti-apoptotic mechanisms. We believe that this manuscript is informative and useful for researchers pursuing the related alleviation of post-menopausal AS via anti-inflammatory and anti-apoptotic mechanisms.

6.
PLoS One ; 12(8): e0182232, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28767687

RESUMO

Analyzing large-scale spatial-temporal k-anonymity datasets recorded in location-based service (LBS) application servers can benefit some LBS applications. However, such analyses can allow adversaries to make inference attacks that cannot be handled by spatial-temporal k-anonymity methods or other methods for protecting sensitive knowledge. In response to this challenge, first we defined a destination location prediction attack model based on privacy-sensitive sequence rules mined from large scale anonymity datasets. Then we proposed a novel on-line spatial-temporal k-anonymity method that can resist such inference attacks. Our anti-attack technique generates new anonymity datasets with awareness of privacy-sensitive sequence rules. The new datasets extend the original sequence database of anonymity datasets to hide the privacy-sensitive rules progressively. The process includes two phases: off-line analysis and on-line application. In the off-line phase, sequence rules are mined from an original sequence database of anonymity datasets, and privacy-sensitive sequence rules are developed by correlating privacy-sensitive spatial regions with spatial grid cells among the sequence rules. In the on-line phase, new anonymity datasets are generated upon LBS requests by adopting specific generalization and avoidance principles to hide the privacy-sensitive sequence rules progressively from the extended sequence anonymity datasets database. We conducted extensive experiments to test the performance of the proposed method, and to explore the influence of the parameter K value. The results demonstrated that our proposed approach is faster and more effective for hiding privacy-sensitive sequence rules in terms of hiding sensitive rules ratios to eliminate inference attacks. Our method also had fewer side effects in terms of generating new sensitive rules ratios than the traditional spatial-temporal k-anonymity method, and had basically the same side effects in terms of non-sensitive rules variation ratios with the traditional spatial-temporal k-anonymity method. Furthermore, we also found the performance variation tendency from the parameter K value, which can help achieve the goal of hiding the maximum number of original sensitive rules while generating a minimum of new sensitive rules and affecting a minimum number of non-sensitive rules.


Assuntos
Segurança Computacional , Algoritmos , Bases de Dados de Ácidos Nucleicos , Modelos Teóricos , Espaço Pessoal
7.
PLoS One ; 11(8): e0160629, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27508502

RESUMO

Spatial-temporal k-anonymity has become a mainstream approach among techniques for protection of users' privacy in location-based services (LBS) applications, and has been applied to several variants such as LBS snapshot queries and continuous queries. Analyzing large-scale spatial-temporal anonymity sets may benefit several LBS applications. In this paper, we propose two location prediction methods based on transition probability matrices constructing from sequential rules for spatial-temporal k-anonymity dataset. First, we define single-step sequential rules mined from sequential spatial-temporal k-anonymity datasets generated from continuous LBS queries for multiple users. We then construct transition probability matrices from mined single-step sequential rules, and normalize the transition probabilities in the transition matrices. Next, we regard a mobility model for an LBS requester as a stationary stochastic process and compute the n-step transition probability matrices by raising the normalized transition probability matrices to the power n. Furthermore, we propose two location prediction methods: rough prediction and accurate prediction. The former achieves the probabilities of arriving at target locations along simple paths those include only current locations, target locations and transition steps. By iteratively combining the probabilities for simple paths with n steps and the probabilities for detailed paths with n-1 steps, the latter method calculates transition probabilities for detailed paths with n steps from current locations to target locations. Finally, we conduct extensive experiments, and correctness and flexibility of our proposed algorithm have been verified.


Assuntos
Modelos Teóricos , Algoritmos , Cadeias de Markov , Probabilidade , Processos Estocásticos
8.
Zhongguo Zhen Jiu ; 32(7): 587-90, 2012 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-22997783

RESUMO

OBJECTIVE: To use electroacupuncture (EA) of different waveforms to treat peripheral facial paralysis and assess the clinical efficacies of 3 kinds of EA waveforms (continuous wave, disperse-dense wave and intermittent wave). METHODS: One hundred and twenty-nine cases of Bell's palsy were randomly divided into a continuous wave group (45 cases), a disperse-dense wave group (40 cases) and an intermittent wave group (44 cases). The acupoints were Dicang (ST 4), Jiache (ST 6), Taiyang (EX-HN 5), Xiaguan (ST 7), Hegu (LI 4), etc. The House-Brackmann (H-B) scale was used in the assessment on the day of the inclusion, in the 1st, 2nd, 3rd and 4th sessions of treatment and in 1st and 3rd months of the follow-up visit after the end of treatment separately. RESULTS: The cured rates were 68.9% (31/45), 60.0% (24/40) and 65.9% (29/44) in the continuous wave group, the disperse-dense wave group and the intermittent wave group separately. The results of the rank sum test showed that the efficacy comparison among the groups did not present the statistically significant difference (P > 0.05). CONCLUSION: Electroacupuncture achieves the significant clinical efficacy on peripheral facial paralysis and there are no any significant differences in the efficacy among the different waveforms. It is suggested that the clinical efficacy of electroacupuncture on the disease has nothing significant correlation with the waveforms.


Assuntos
Eletroacupuntura/métodos , Paralisia Facial/terapia , Adulto , Idoso , Eletroacupuntura/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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