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1.
World J Urol ; 42(1): 150, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38478063

RESUMO

PURPOSE: Oral chemolysis is an effective and non-invasive treatment for uric acid urinary stones. This study aimed to classify urinary stones into either pure uric acid (pUA) or other composition (Others) using non-contrast-enhanced computed tomography scans (NCCTs). METHODS: Instances managed at our institution from 2019 to 2021 were screened. They were labeled as either pUA or Others based upon composition analyses, and randomly split into training or testing data set. Several instances contained multiple NCCTs which were all collected. In each of NCCTs, individual urinary stone was treated as individual sample. From manually drawn volumes of interest, we extracted original and wavelet radiomics features for each sample. The most important features were then selected via the Least Absolute Shrinkage and Selection Operator for building the final model on a Support Vector Machine. Performance on the testing set was evaluated via accuracy, sensitivity, specificity, and area under the precision-recall curve (AUPRC). RESULTS: There were 302 instances, of which 118 had pUA urinary stones, generating 576 samples in total. From 851 original and wavelet radiomics features extracted for each sample, 10 most important features were ultimately selected. On the testing data set, accuracy, sensitivity, specificity, and AUPRC were 93.9%, 97.9%, 92.2%, and 0.958, respectively, for per-sample prediction, and 90.8%, 100%, 87.5%, and 0.902, respectively, for per-instance prediction. CONCLUSION: The machine learning algorithm trained with radiomics features from NCCTs can accurately predict pUA urinary stones. Our work suggests a potential assisting tool for stone disease treatment selection.


Assuntos
Nefrolitíase , Cálculos Urinários , Urolitíase , Humanos , Ácido Úrico/análise , Radiômica , Cálculos Urinários/diagnóstico por imagem , Aprendizado de Máquina , Estudos Retrospectivos
2.
Turk J Chem ; 47(1): 294-306, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37720860

RESUMO

The present work aimed to investigate inclusion complexes of squalene with various cyclodextrins (native ß-cyclodextrin and methyl-ß-cyclodextrin). The production of squalene-ß-cyclodextrin inclusion complex was obtained using Response Surface Methodology and obtained inclusion complexes were studied with FTIR spectroscopy, X-ray diffractometry, thermal analysis, and 1H-NMR spectrometry. At the same time, squalene content was determined by reversed-phase high-performance liquid chromatography. All results confirmed that squalene was successfully involved in the cyclodextrin cavities. Optimizing the condition in preparation for the squalen-ß-cyclodextrin inclusion complex yielded 54.3% with squalene content of 9.01%. The essential difference for the inclusion complex of squalene with methylated beta-cyclodextrin was that no precipitate formed in the initial mixture, and the complex was more efficiently dispersed in water. The conclusions of the inclusion complex formation were confirmed by computer simulation by optimizing the complex geometry using the DFT, MM2, and MP3 methods.

3.
Environ Sci Pollut Res Int ; 30(1): 1898-1907, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35927402

RESUMO

Phytoremediation is one of the most powerful and viable solutions for developing countries to clean the soil and water bodies from metallic pollutants. Cyperus alternifolius Linn. (CAL), a tropical wetland plant, has been widely researched for removing harmful contaminants due to its hyperaccumulation ability. However, the waste biomass of phytoremediation processing may risk secondary environmental pollution. Thus, the preparation and application of biochar from metal-contaminated plants can be considered a new approach. In a 60-day experiment, CAL plants were irrigated with different concentrations of Zn(II) (200, 700, 1200, 1700, and 2200 mg·L-1), and then the plants were converted into biochar via the pyrolysis process. The characteristics of biochar including of surface composition and morphology, phase formation, and optical property were analyzed. The biochar enriched with Zn(II) at 1200 mg·L-1 had a bandgap value of 3.17 eV and consisted of carbon microparticles intermingled with ZnO and SiO2 nanoparticles. Furthermore, the adsorption and photocatalysis of the biochar were studied in the discolouration of methylene blue (MB), as a test reaction, with the maximum MB removal capacities of 55.2 mg·g-1. Such results will serve as the basis for new research aiming at the potential for reusing metal-contaminated plants to produce efficient depolluting biochar.


Assuntos
Cyperus , Poluentes do Solo , Biodegradação Ambiental , Dióxido de Silício , Carvão Vegetal , Plantas
4.
RSC Adv ; 11(58): 36626-36635, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-35494394

RESUMO

A series of Zr-sulfonic-based metal-organic frameworks have been synthesized by the solvothermal method, namely VNU-17 and VNU-23. Particularly, VNU-17 and VNU-23 adopt the sulfonate group (SO3 -) moieties densely packed within their structure, which can efficiently uptake MB+ from wastewater. The maximum adsorption capacity for MB+ onto VNU-23 is up to 1992 mg g-1 at pH = 7, which is more than five times that of activated carbon and possesses the highest value among all the reported MOF materials. In addition, VNU-23 retains the adsorption uptake of MB for at least five cycles. The adsorption isotherms and kinetic studies reveal that MB+ dye adsorption onto VNU-23 fits a Langmuir isotherm and the pseudo second order kinetic model. Furthermore, the ultra-high adsorption capacity of VNU-23 for MB dye can be accounted for by the suitable pore/channel size together with electrostatic attraction and π-π interactions. These results indicate that VNU-23 can be utilized as a promising candidate for removing MB+ from an aqueous medium.

5.
ACS Omega ; 5(24): 14481-14493, 2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-32596586

RESUMO

Thiosemicarbazide-modified cellulose (MTC) has been studied for removing heavy metals in the water source or for extracting some precious metals. The conditions of synthesis of MTC and Cu(II) removal were optimized by single-variable analysis through oxidation-reduction on titration and photometry. The results of Fourier-transform infrared spectroscopy, Brunauer-Emmett-Teller, and thermogravimetric analyses show that MTC exists in the thioketone form with a high surface area and heat durability. The Cu(II) removal was of pseudo-second order and the isotherm equation correlated best with the Langmuir equation. MTC has the maximum capacity of adsorption, which is q m = 106.3829 mg g-1. Furthermore, MTC can be regenerated without the loss of adsorption efficiency after ten cycles of adsorption and desorption.

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