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1.
Artigo em Inglês | MEDLINE | ID: mdl-37672375

RESUMO

Recent studies have focused on using natural language (NL) to automatically retrieve useful data from database (DB) systems. As an important component of autonomous DB systems, the NL-to-SQL technique can assist DB administrators in writing high-quality SQL statements and make persons with no SQL background knowledge learn complex SQL languages. However, existing studies cannot deal with the issue that the expression of NL inevitably mismatches the implementation details of SQLs, and the large number of out-of-domain (OOD) words makes it difficult to predict table columns. In particular, it is difficult to accurately convert NL into SQL in an end-to-end fashion. Intuitively, it facilitates the model to understand the relations if a "bridge" transition representation (TR) is employed to make it compatible with both NL and SQL in the phase of conversion. In this article, we propose an automatic SQL generator with TR called GTR in cross-domain DB systems. Specifically, GTR contains three SQL generation steps: 1) GTR learns the relation between questions and DB schemas; 2) GTR uses a grammar-based model to synthesize a TR; and 3) GTR predicts SQL from TR based on the rules. We conduct extensive experiments on two commonly used datasets, that is, WikiSQL and Spider. On the testing set of the Spider and WikiSQL datasets, the results show that GTR achieves 58.32% and 71.29% exact matching accuracy which outperforms the state-of-the-art methods, respectively.

2.
ACS Omega ; 7(41): 36776-36785, 2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36278092

RESUMO

Tobacco features chemical compositions different from that of raw lignocellulosic biomass. Currently, the performance of network models, like Bio-Chemical Percolation Devolatilization (Bio-CPD), on tobacco pyrolysis is unclear, and only global kinetics have been proposed for tobacco devolatilization, which does not have the versatility for a wide range of heating conditions and tobacco types. To address this issue, the present work first assessed the performance of the Bio-CPD model on tobacco pyrolysis through an a priori study, which showed large deviations. Afterward, an extended Chemical Percolation Devolatilization model for tobacco pyrolysis (Toba-CPD) was developed by modifying the kinetic parameters using a grid-search optimization strategy. The process of grid-search optimization strategy is based on the kinetic parameters of the Bio-CPD model and modified with experimental results of 11 tobacco types under a wide range of heating rates. Finally, the performance of Toba-CPD was measured with experimental results which were not used during parameters optimization. Results demonstrated that the Toba-CPD models could well reproduce the pyrolysis of various tobacco types under a wide range of heating rates (R 2 > 0.957).

3.
ACS Omega ; 7(30): 26407-26415, 2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35936416

RESUMO

As the most basic indexes to evaluate the quality of tobacco, the contents of routine chemical constituents in tobacco are mainly detected by continuous-flow analysis at present. However, this method suffers from complex operation, time consumption, and environmental pollution. Thus, it is necessary to establish a rapid accurate detection method. Herein, different from the ongoing research studies that mainly chose near-infrared spectroscopy as the information source for quantitative analysis of chemical components in tobacco, we proposed for the first time to use the thermogravimetric (TG) curve to characterize the chemical composition of tobacco. The quantitative analysis models of six routine chemical constituents in tobacco, including total sugar, reducing sugar, total nitrogen, total alkaloids, chlorine, and potassium, were established by the combination of TG curve and partial least squares algorithm. The accuracy of the model was confirmed by the value of root mean square error for prediction. The models can be used for the rapid accurate analysis of compound contents. Moreover, we performed an in-depth analysis of the chemical mechanism revealed by the result of the quantitative model, namely, the regression coefficient, which reflected the correlation degree between the six chemicals and different stages of the tobacco thermal decomposition process.

4.
ACS Omega ; 7(1): 1420-1427, 2022 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-35036803

RESUMO

In the present work, experimental and kinetic studies are conducted to explore and model tobacco pyrolysis characteristics under a wide range of heating conditions. First, thermal decomposition processes of a tobacco sample were investigated using thermogravimetric analysis/difference thermogravimetry (TGA/DTG) experiments under a wide range of heating rates (10-500 K/min), and the TGA/DTG profiles were compared to highlight the effect of heating rate on the pyrolysis characteristics. The results showed that the tobacco sample was sufficiently devolatilized at 1173.15 K (900 °C) and the final volatiles yields were not sensitive to the heating rate. Moreover, it was illustrated that the DTG curve presents a polymerization trend with the increase in heating rate. Then, kinetic parameters, including total component mass fraction, preexponential factor, and activation energy, were derived by deconvolution from TG/DTG profiles for each component with a one-step kinetic framework, and the correlations between kinetic parameters and heating rates were further explored and modeled. The results illustrated that four subpeaks can be found in the deconvolution, indicating the four components (volatile components, hemicellulose, cellulose, and lignin). In addition, the activation energy of each component was found to be insensitive with heating rate (with standard deviation less than 20%). Therefore, an average activation energy was used for each component to avoid the compensation effect and a power correlation between the heating rate and the preexponential factor could be found. A posteriori analysis also confirmed the validity of this correlation.

5.
Anim Biosci ; 34(3): 443-448, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33332949

RESUMO

OBJECTIVE: Astaxanthin is a natural super antioxidant. The present study was carried out to investigate the effect of astaxanthin rich Phaffia rhodozyma (PR) supplementation in diets on laying production performance, egg quality, antioxidant defenses and immune defenses in laying hens. METHODS: A total of five hundred and twelve 60-week-old Lohmann Brown laying hens (2,243±12 g) were randomly assigned to four groups, each including 4 replicates with 32 birds per replicate. Astaxanthin rich PR was added to corn-soybean meal diets to produce experimental diets containing 0 (Control), 800 mg/kg, 1,200 mg/kg, and 1,600 mg/kg PR, respectively. The astaxanthin content in the diet was 0.96 mg/kg, 1.44 mg/kg and 1.92 mg/kg respectively. RESULTS: Results showed that dietary PR supplementation tended to increase daily feed intake (p = 0.0512). There was no effect of astaxanthin rich PR on Haugh units, albumen height, egg shape index, eggshell strength, and eggshell thickness at weeks 6 (p>0.05). However, egg yolk color was significantly improved (p<0.05). In addition, astaxanthin rich PR supplementation significantly increased serum glutathione peroxidase and superoxide dismutase activity (p<0.05), increased serum immunoglobulin G content (p<0.05), and reduced malondialdehyde content (p<0.05) in laying hens. CONCLUSION: In conclusion, astaxanthin rich PR can improve the color of egg yolk, enhance the antioxidant defenses, and regulate the immune function.

6.
Foods ; 9(12)2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33291825

RESUMO

To study the effects of deep-ocean water concentrate (DOWC) on sake quality, Taichung No. 10 indica rice (Oryza sativa subsp. indica) and Tainan No. 11 japonica rice (O. sativa subsp. japonica) were used as raw materials, and basic physicochemical property parameters in shochu were analyzed differentially. Sake fermentation mash analysis results revealed that DOWC addition did not significantly affect the basic physicochemical properties during sake brewing, but it significantly reduced citric acid and malic acid contents in Taichung No. 10 indica rice sake sample by 52-66% and 73-93%, respectively. DOWC addition significantly increased citric acid content in Tainan No. 11 japonica rice sake sample by 32-202%. Rice shochu analysis results revealed that DOWC addition significantly increased isoamyl acetate, ethyl hexanoate, and ethyl octanoate contents in shochu made from japonica rice and indica rice, respectively. The results indicate that rice variety directly affects the types of volatile compounds in rice shochu. Principal component analysis and sensory evaluation results revealed that DOWC addition affected the composition of volatile compounds in the two types of rice shochu and resulted in differences in flavor evaluation. DOWC addition affects yeast metabolites and directly changes the volatile compound composition and flavor of rice shochu.

7.
Wilderness Environ Med ; 31(2): 247-254, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32734899

RESUMO

INTRODUCTION: The UK undergraduate medicine curriculum provides insufficient opportunities for medical students to explore the field of wilderness medicine, despite interest in the area. The student-led Cambridge University Wilderness Medicine Society devised a low-cost wilderness medicine teaching weekend that can be replicated at other institutions. METHODS: The weekend course consisted of small-group lessons introducing the roles of the expedition doctor and expedition leader and the assessment and management of acute conditions in remote environments. This was followed by a 3-station circuit to teach the principles of casualty triage, splinting, and construction of rope stretchers. These skills were then practiced in simulations in which participants rotated roles as care providers and patients. Participant confidence was compared before the course and immediately on course completion using the related-samples Wilcoxon signed-ranks test with significance accepted at P<0.05. Usefulness of course content and perceptions of learning were also assessed. RESULTS: Sixty-one medical students attended the wilderness teaching weekend and completed the structured feedback questionnaires. Participants rated the course highly in terms of usefulness of course content (mean±SD=18.3±1.9, range=12-20) and perceptions of learning (mean±SD=37.6±2.6, range=31-40), with 92% of participants "strongly agreeing" that the course was of high quality. There was an improvement in perceived confidence after course completion (P<0.001). CONCLUSIONS: We have demonstrated that a teaching program consisting of structured, low-cost "teaching weekends" is a potential solution to the lack of centralized national wilderness medicine teaching and can be integrated, with minimal disruption, into the undergraduate curriculum.


Assuntos
Currículo , Educação Médica/organização & administração , Medicina Selvagem/educação , Humanos , Estudantes de Medicina , Reino Unido
9.
Nano Lett ; 18(6): 3785-3791, 2018 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-29782802

RESUMO

Single-atom catalysts exhibit high selectivity in hydrogenation due to their isolated active sites, which ensure uniform adsorption configurations of substrate molecules. Compared with the achievement in catalytic selectivity, there is still a long way to go in exploiting the catalytic activity of single-atom catalysts. Herein, we developed highly active and selective catalysts in selective hydrogenation by embedding Pt single atoms in the surface of Ni nanocrystals (denoted as Pt1/Ni nanocrystals). During the hydrogenation of 3-nitrostyrene, the TOF numbers based on surface Pt atoms of Pt1/Ni nanocrystals reached ∼1800 h-1 under 3 atm of H2 at 40 °C, much higher than that of Pt single atoms supported on active carbon, TiO2, SiO2, and ZSM-5. Mechanistic studies reveal that the remarkable activity of Pt1/Ni nanocrystals derived from sufficient hydrogen supply because of spontaneous dissociation of H2 on both Pt and Ni atoms as well as facile diffusion of H atoms on Pt1/Ni nanocrystals. Moreover, the ensemble composed of the Pt single atom and nearby Ni atoms in Pt1/Ni nanocrystals leads to the adsorption configuration of 3-nitrostyrene favorable for the activation of nitro groups, accounting for the high selectivity for 3-vinylaniline.

10.
Eur Arch Otorhinolaryngol ; 275(5): 1123-1128, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29478077

RESUMO

BACKGROUND: There are a variety of surgical techniques which can be used to treat structural nasal obstruction. Airwayplasty is a procedure, combining septoplasty, turbinate surgery, and nasal wall lateralization. The article reports the long-term result of this novel approach. METHODOLOGY: Patients who have evidence of structural nasal obstruction were offered the option to have airwayplasty under the senior surgeon. Patients were asked to quantify the severity and the impact of their nasal obstruction using the Visual Analogue Scale (VAS) and the validated Sino-Nasal Outcome Test (SNOT-22) pre-operatively and post-operatively. RESULTS: The mean total SNOT-22 score and VAS score showed a reduction of more than 50% with significant p value at 6 and 12 months post-operatively. CONCLUSIONS: This novel approach to nasal obstruction can provide good long-term functional results for patients suffering from nasal obstruction.


Assuntos
Obstrução Nasal/cirurgia , Septo Nasal/cirurgia , Rinoplastia/métodos , Conchas Nasais/cirurgia , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Obstrução Nasal/diagnóstico , Obstrução Nasal/etiologia , Estudos Prospectivos , Resultado do Tratamento
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