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1.
Int J Clin Pract ; : e14197, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33792126

RESUMO

BACKGROUND: COVID-19 has been sweeping the world since it emerged in late December 2019. However, little is known about cardiac injury in hospitalised COVID-19 patients. This study is to investigate the incidence and characteristics of myocardial injury in COVID-19 patients admitted in hospital. METHODS: Fifty-four COVID-19 patients were enrolled in one ward in Tongji Hospital, Wuhan, China, and 5 were excluded due to missing cardiac troponin I levels. Forty-nine participants were included in the final analysis. The clinical manifestations of hospitalised patients were analysed. Patients were divided into two groups, cardiac injury group and non-cardiac injury group, based on whether cardiac troponin I was elevated. Epidemic characteristics and laboratory test results were analysed in these two group. RESULTS: The average age of patients in the cardiac injury group was older (68.0 years old) than that in the non-cardiac injury group (61.5 years old). The percentages of patients with diabetes and critically severe pneumonia in the cardiac injury group were 38.5% and 38.5%, respectively. Lymphocytes were decreased in 53.1% of all enrolled patients, but this decrease was more prominent (76.9%) in the cardiac injury group than the non-cardiac injury group (44.4%). Patients in the cardiac injury group also had lower platelet counts. CONCLUSIONS: COVID-19 can cause cardiac injury in many patients. It is more common in older patients and patients with diabetes and is associated with a significant decrease in lymphocytes.

2.
Anal Bioanal Chem ; 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33825005

RESUMO

A cost-effective, facile, and sensitive fluorescence sensing strategy for Pb2+ ion detection has been developed based on the fluorescence resonance energy transfer (FRET) between carbon quantum dots (CQDs) and Au nanoparticles (NPs). Glutathione (GSH)-synthesized CQDs acted as both the fluorescence donor and the sorbent to extract Pb2+ ions from the solution via Pb-GSH complexes. Pb2+ ions on CQDs reacted with -SH groups on AuNPs to generate sandwich-type Au-PdS-CQDs, leading to a dramatic decrease in the fluorescence of the CQDs. To expand the potential applications of this strategy, we constructed a sensing strategy using self-organized TiO2 nanotube arrays (TiNTs). The high aspect ratio and transparency for light emitted from the CQDs enabled the TiNTs to serve as a sensitive solid visual platform for the highly selective detection of Pb2+ ions with a detection limit as low as 4.1 × 10-8 mg mL-1. More importantly, the long observation length combined with a small volume enabled a sample acquisition volume of only 2.1 × 10-3 µL, which is smaller than the traditional fluorescence analysis in solution and on commercially available test paper, thus endowing this visual platform with the potential for use in single-cell diagnostics.

3.
Chin Med J (Engl) ; 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33813517

RESUMO

BACKGROUND: Compared to adult studies, studies which involve the treatment of pediatric congenital hypogonadotropic hypogonadism (CHH) are limited and no universal treatment regimen is available. The aim of this study was to evaluate the feasibility of human chorionic gonadotropin (hCG)/human menopausal gonadotropin (hMG) therapy for treating male adolescents with CHH. METHODS: Male adolescent CHH patients were treated with hCG/hMG (n = 20) or a gonadotropin-releasing hormone (GnRH) pump (n = 21). The treatment was divided into a study phase (0-3 months) and a follow-up phase (3-12 months). The testicular volume (TV), penile length (PL), penis diameter (PD), and sex hormone levels were compared between the two groups. The TV and other indicators between the groups were analyzed using a t-test (equal variance) or a rank sum test (unequal variance). RESULTS: Before treatment, there was no statistical difference between the two groups in terms of the biochemistry, hormones, and other demographic indicators. After 3 months of treatment, the TV of the hCG/hMG and GnRH groups increased to 5.1 ±â€Š2.3 mL and 4.1 ±â€Š1.8 mL, respectively; however, the difference was not statistically significant (P > 0.05, t = 1.394). The PL reached 6.9 ±â€Š1.8 cm and 5.1 ±â€Š1.6 cm (P < 0.05, t = 3.083), the PD reached 2.4 ±â€Š0.5 cm and 2.0 ±â€Š0.6 cm (P < 0.05, t = 2.224), respectively, in the two groups. At the end of 6 months of treatment, biomarkers were in normal range in the two groups. Compared with the GnRH group, the testosterone (T) level and growth of PL and PD were significantly greater in the hCG/hMG group (all P < 0.05). While the TV of both groups increased, the difference was not statistically significant (P > 0.05, t = 0.314). After 9 to 12 months of treatment, the T level was higher in the hCG/hMG group. Other parameters did not exhibit a statistical difference. CONCLUSIONS: The hCG/hMG regimen is feasible and effective for treating male adolescents with CHH. The initial 3 months of treatment may be a window to optimally observe the strongest effects of therapy. Furthermore, results from the extended time-period showed positive outcomes at the 1-year mark; however, the long-term effectiveness, strengths, and weaknesses of the hCG/hMG regimen require further research. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02880280; https://clinicaltrials.gov/ct2/show/NCT02880280.

4.
Materials (Basel) ; 14(5)2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33804545

RESUMO

In this work, the fatigue crack growth (FCG) behavior and fatigue damage mechanism of the 2.25Cr1Mo0.25V steel welded joint used in hydrogenation reactors were investigated. The multi-pass welding was carried out to manufacture the welded joint using the combined shielded metal arc welding (SMAW) and submerged automatic arc welding (SAAW) processes. The FCG behavior of different zones in the welded joint, including the base metal (BM), the heat-affected zone (HAZ) and the weld metal (WM), were studied by compact tension tests. Moreover, the acoustic emission (AE) technique was used to monitor AE signals generated from FCG process for further understanding FCG behavior and fatigue mechanisms. Additionally, the microstructures and fracture surfaces of different specimens were observed by optical microscopy (OM) and scanning electron microscopy (SEM). The results revealed that the microstructure of BM is fine granular bainite, while the WM shows coarser bainite grains. The HAZ exhibits the most significant inhomogeneity with large dispersion of grain size. FCG results showed that the HAZ exhibits much higher fatigue crack growth rate (FCGR) at low ΔK values, while the BM shows the most superior fatigue resistance. The AE technique is successful in monitoring and identifying damage evolutions during the FCG process. Moreover, an enhanced AE activity is observed in FCG of the WM specimen, which is attributed to the combined influence of the formation of numerous secondary cracks and coarse-grained microstructures.

7.
J Nephrol ; 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33770396

RESUMO

BACKGROUND: Despite growing evidence about the benefits of physical activity and exercise in patients receiving dialysis, physical inactivity is highly prevalent. This may be due to uncertainty and lack of appropriate guidance about exercise, or driven by the relative barriers and benefits that patients perceive. Understanding these perceptions in dialysis patients may inform interventions aimed to increase exercise participation. METHODS: Perceived benefits and barriers to exercise were measured by the 'Dialysis Patient-perceived Exercise Benefits and Barriers Scale' (DPEBBS). Self-reported physical activity status was assessed by the 'General Practice Physical Activity Questionnaire'. Barriers and benefits to exercise were classed as binary variables (i.e. yes and no). Frequency analyses and chi-squared tests were conducted to compare the differences perceived by people on haemodialysis (HD) and peritoneal dialysis (PD). Binominal logistical regression was performed to determine which perceived barriers and benefits had the biggest impact on physical activity status. RESULTS: One thousand twenty-two HD and 124 PD patients completed the DPEBBS. A greater proportion of HD than PD patients reported 'reduces body pain' (P = 0.013), 'delays decline in body function' (P = 0.01), and 'improves quality of life' (P = 0.033) as benefits of exercise. No differences in barriers were observed. Tiredness was the most reported barrier to exercise. Patients who perceived 'other comorbidities' (OR 3.389, P < 0.001) or 'burden of family' (OR 3.168, P < 0.001) as barriers were 3 times more likely to be inactive. CONCLUSIONS: Dialysis patients perceive several barriers which may prevent them from engaging in physical activity. Addressing these barriers may be key to increasing participation in physical activity and exercise.

8.
ACS Appl Mater Interfaces ; 13(11): 12972-12981, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33689269

RESUMO

Effective isolation and removal of target tumor cells from patients' peripheral blood are of great importance to clinical prognosis and recovery. However, the extremely low quantity of target cells in peripheral blood becomes one of the challenges in this respect. Herein, we design and synthesize an innovative nanostructure based on magnetic TiO2 nanotubes with Pt nanoparticles' asymmetrical decoration for effectively capturing and inactivating target cells. Using CCRF-CEM as the model cell, the resulting nanotubes with accurate modification of recognition probes exhibit high selectivity and cell-isolation efficiency upon real blood samples. Particularly, the target cells are selectively captured at a low concentration with a recovery rate of 73.0 ± 11.5% at five cells per milliliter for whole blood samples. Consequently, benefitting from the remarkable photocatalytic activity of the Janus nanotubes, these isolated cells can be rapidly inactivated via light-emitting diode (LED) irradiation with an ignorable effect on normal cells. This work offers a new paradigm for high-efficient isolating/killing target cells from a complex medium.

9.
Phys Chem Chem Phys ; 23(11): 6613-6622, 2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33705501

RESUMO

Recently, transition metal borides (MBenes, analogous to MXenes) have attracted interest due to their potential applications in energy conversion and storage. In this work, we performed density functional theory calculations to systematically explore the exfoliation properties of 14 MAlB phases and their water splitting and N2 reduction reaction (NRR) performances. Results showed a linear relationship between the binding energy and exfoliation energy with the coefficient (R2) of 0.95, indicating that the lower the binding energy of element Al in MAlB (M2AlB2), the higher the exfoliation energy required to synthesize monolayer MB from MAlB (M2AlB2). NiB (B site) was predicted to possess the best electrocatalytic activity for water splitting, hydrogen evolution reaction (HER), and oxygen evolution reaction (OER) among the studied MBenes, and overpotentials on the NiB surface were calculated to be 0.08 V (for HER) and 0.37 V (for OER), respectively. The electronic properties and dynamic simulations indicated that NiB is the best candidate catalyst for water splitting. Conversely, the Fe site on FeB (FeB-Fe) was predicated to have the highest nitrogen reduction reaction (NRR) activity among the studied MBenes, with the overpotential ηNRR of 0.11 V. Furthermore, the B site of TaB (TaB-B) was identified as the best NRR catalyst against HER among the studied MBenes considering the HER side reaction.

10.
Artigo em Inglês | MEDLINE | ID: mdl-33728608

RESUMO

This study was aimed to evaluate the toxic effects of different concentrations (23, 90, 360 mg/kg BW) of atrazine (ATZ) on immune function in BALB/c mice. Some parameters of general immunotoxicity, humoral immunity, cellular immunity, and non-specific immunity were tested. The studies showed that the high-dose ATZ induced a significant reduction in the final body weight of mice, the absolute and relative weights of spleen, the counts of white blood cell (WBC), lymphocyte (LYM), monocyte (MON), and the number of splenocyte. An increase in the level of alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN), and cholesterol (CHO) in the high-dose ATZ group was observed. Pathological examination showed that the medium- and high-doses of ATZ caused atrophy and destruction of thymus, spleen, and hepatorenal toxicity. The serum interleukin-5(IL-5) level of mice and the number of plaque-forming cell (PFC) in spleen cells in the high-dose ATZ group decreased significantly while there was a significant increase of the serum immunoglobulin G (IgG) in the high-dose ATZ group when compared to the negative control group. In the high-dose ATZ group, the proliferation ability of T and B lymphocytes as well as the delayed-type hypersensitivity (DTH) response were significantly decreased. The low-dose ATZ (23 mg/kg BW) caused a significant decrease in the number of WBC and neutrophil (NEUT), as well as the proportion of polychromatic and normoblast. In summary, we thought the low-dose ATZ has a slight effect on the immune system; it can be preliminarily concluded that the lowest observed adverse effect level (LOAEL) of atrazine is 23 mg/kg BW in mice. Atrazine can cause immunotoxicity mainly through cellular and humoral immunity pathways.

11.
Cancer Invest ; : 1-11, 2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33650922

RESUMO

Preoperative magnetic resonance imaging was analyzed by four radiologists regarding local tumor staging (T and N) and the presence of extramural vascular involvement. An astonishingly high sensitivity for the detection of T 3/4 tumors (κ (quadratic weighted statistics constant) = 0.67), with considerably lower sensitivity for T 3 cd/4 tumors (κ = 0.51), high sensitivity for serosal involvement 76-87% (κ = 0.65) and extramural vascular involvement (87-98%, κ = 0.56). Sensitivity and specificity for lymph node involvement is lower (κ = 0.57). Magnetic resonance imaging with adequate experience can accurately detect tumors with invasion through the bowel wall and their prognostic factors.

12.
Cancer Biol Med ; 2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33724741

RESUMO

OBJECTIVE: In this post-hoc analysis, we evaluated anlotinib treatment-induced hypertension as a potential predictive factor of efficacy in esophageal squamous cell carcinoma (ESCC) patients. METHODS: A total of 109 patients enrolled in the anlotinib group in a phase 2 trial were included. The tumor response was assessed by computed tomography at week 3, week 6, and then every 6 weeks until progressive disease was observed. The primary endpoint of the study was progression free survival (PFS). The secondary endpoints included overall survival (OS) and objective response rate (ORR). RESULTS: In all patients, the median PFS was 3.02 months [95% confidence interval (CI): 2.63-3.65 months] and the OS was 6.11 months (95% CI: 4.40-7.79 months). The ORR was 7.34% (95% CI: 3.22%-13.95%). A total of 59 (54%) patients were diagnosed with treatment-induced hypertension (Group A), and the remaining patients (n = 50, 46%) were in Group B. Baseline prognostic factors were similar between the 2 groups. Patients in Group A had a longer PFS and OS and higher ORR. When stratifying patients using a previously known history of hypertension, treatment-induced hypertension was a predictor only for patients without previous hypertension, who had longer PFS [hazard ratio (HR): 0.40, 95% CI: 0.24-0.68] and OS (HR: 0.37, 95% CI: 0.21-0.67). CONCLUSIONS: We showed, for the first time, a correlation between treatment-induced hypertension and better prognoses in recurrent or metastatic ESCC patients treated with anlotinib, without a previously known history of hypertension. Treatment-induced hypertension may be a simple and low cost predictor for anlotinib antitumor efficacy in these patients, which may also reflect the intended target inhibition.

14.
Ying Yong Sheng Tai Xue Bao ; 32(2): 425-432, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33650351

RESUMO

The trade-off between leaf size and number is the basis for plant growth strategies. It is of great significance to study the underlying mechanism of leaf size and number trade-offs for well understanding plant growth strategies. In this study, leaf size was expressed by the dry mass of single leaf, while leafing intensity was expressed by the number of leaves per unit stem volume. We used standardized major axis regression analysis method to examine the trade-off relationship between leaf size and number in Hulunbuir grassland. There was a significant negative isometric-growth trade-off between leaf size and number in Chenqicuogang (typical steppe) and Chenqibayi (meadow steppe). There was a significant negative allometric-growth trade-off between leaf size and number in Xeltala (meadow steppe). The underlying mechanism of the relationship between leaf size and number depended on the leaf and stem biomass allocation mechanism and the changes of the stem tissue density.


Assuntos
Pradaria , Folhas de Planta , Biomassa , China , Análise de Regressão
15.
Sci Rep ; 11(1): 5974, 2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33727661

RESUMO

We investigated the effect of CYP2C19 polymorphisms on the clinical outcomes of clopidogrel therapy in patients after stenting procedure for cerebral artery stenosis in northeast China. 568 patients performed CYP2C19 genotype screening in the neurosurgery department of our hospital; 154 patients were finally recruited according to the inclusion and exclusion criteria, and followed-up for 6 months. Ischemic events including (1) transient ischemic attack (TIA); (2) stent thrombosis; (3) ischemic stroke; and (4) death were defined as primary clinical endpoints. The frequencies of CYP2C19*1, *2 and *3 alleles in 568 patients were 63.1%, 31.1% and 5.8%, respectively. 154 patients were classified into extensive (65 patients; 42.2%), intermediate (66 patients; 42.9%), and poor (23 patients; 14.9%) metabolizer groups. A χ2 test showed a significant difference in primary clinical endpoints at 6 months (P = 0.04), and a multivariate Cox regression analysis indicated that the CYP2C19 loss-of-function (LOF) alleles associated with post-procedure prognosis. The Kaplan-Meier curve revealed that there was no significant difference in ischemic events between *2 and *3 alleles carriers. Our study verifies that CYP2C19 *2 and *3 have significant impact on the clinical outcomes of clopidogrel therapy in patients with stenting procedure for cerebral artery stenosis in China.

16.
Thorac Cancer ; 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33760397

RESUMO

BACKGROUND: This multicentre, open-label study evaluated the efficacy and safety of antiprogrammed death ligand 1 antibody SHR-1316 plus liposomal irinotecan and 5-fluorouracil as the first-line treatment for patients with advanced esophageal squamous cell carcinoma (ESCC). METHODS: Eligible patients received SHR-1316 (10 mg/kg), liposomal irinotecan (60 mg/m2 for the first cycle, 80 mg/m2 thereafter), and 5-fluorouracil (2400 mg/m2 ) every 14 days until disease progression, intolerable toxicity or withdrawal of consent. The primary endpoint was progression-free survival (PFS). Secondary endpoints were objective response rate (ORR), disease control rate (DCR), overall survival (OS), and safety. RESULTS: We enrolled 23 patients between 11 March 2019 and 31 May 2019. The median follow-up duration was 15.2 months (95% CI 14.2-16.2). The median PFS was 8.5 months (95% CI 1.2-15.8), and ORR and DCR were 52.2% (95% CI 30.1-74.3) and 73.9% (95% CI 54.5-93.3), respectively. The median OS was 11.6 months (95% CI 6.7-16.6). The most common treatment-related grade 3-4 adverse events (AEs) were neutropenia (17.4%), nausea (13.0%), and anorexia (13.0%). Treatment-related serious AEs occurred in two patients. No treatment-related deaths occurred. CONCLUSIONS: SHR-1316 plus liposomal irinotecan and 5-fluorouracil has a promising efficacy and manageable safety profile, and could be a new first-line treatment approach for patients with unresectable locally advanced or distant metastatic ESCC.

17.
Neuroimage ; 233: 117911, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33711483

RESUMO

It is widely accepted that impairment in visual perception impedes children's reading development, and further studies have demonstrated significant enhancement in reading fluency after visual perceptual training. However, the mechanism of the neural linkage between visual perception and reading is unclear. The purpose of this study was to examine the intrinsic functional relationship between visual perception (indexed by the texture discrimination task,TDT) and reading ability (character reading and reading fluency) in Chinese children with developmental dyslexia (DD) and those with typical development (TD). The resting-state functional connectivity (RSFC) between the primary visual cortex (V1, BA17) and the entire brain was analyzed. In addition, how RSFC maps are associated with TDT performance and reading ability in the DD and TD groups was examined. The results demonstrated that the strength of the RSFC between V1 and the left middle frontal gyrus (LMFG, BA9/BA46) was significantly correlated with both the threshold (SOA) of the TDT and reading fluency in TD children but not in DD children. Moreover, LMFG-V1 resting-state connectivity played a mediating role in the association of visual texture discrimination and reading fluency, but not in character reading, in TD children. In contrast, this mediation was absent in DD children, albeit their strengths of RSFC between V1 and the left middle frontal gyrus (LMFG) were comparable to those for the TD group. These findings indicate that typically developing children use the linkage of the RSFC between the V1 and LMFG for visual perception skills, which in turn promote fluent reading; in contrast, children with dyslexia, who had higher TDT thresholds than TD children, could not take advantage of their frontal-occipital connectivity to improve reading fluency abilities. These findings suggest that visual perception plays an important role in reading skills and that children with developmental dyslexia lack the ability to use their frontal-occipital connectivity to link visual perception with reading fluency.

18.
J Mater Chem B ; 9(8): 2016-2024, 2021 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-33544115

RESUMO

Nanomaterial-based artificial enzyme mimetics have attracted increasing attention because of their robust stability, adjustable activity, and cost-effectiveness. In this study, we developed a simple and effective method for the synthesis of highly dispersed ultrafine PdCo alloys with peroxidase- and catalase-like activities. The aberration-corrected transmission electron microscopy analysis verified that the cyanogel precursor in the mesoporous silica nanospheres (MSNs) was converted to PdCo alloy in NH3 at a high temperature. The PdCo alloy was homogenously distributed in MSNs as ultrafine and monodispersed particles. By selectively removing the Co species from the binary alloy through an acid-leaching approach, the role of each component in the enzyme-like mimetics was systematically studied. Using glutathione (GSH) as the model analyte, the potential application of PdCo@MSNs in GSH detection from complex cell media was confirmed via colorimetric assay. The ultrafine alloy size, double mimetic activities, and abundant loading space of PdCo@MSNs make them promising not only in clinical diagnosis but also in overcoming hypoxia-induced photodynamic therapy resistance in tumor treatment.

19.
Sci Total Environ ; 773: 145403, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33582342

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are one of the most widely distributed persistent organic pollutants (POPs) in the environmental media. PAHs have been widely concerned due to their significant health risk and adverse effects to human and animals. Currently, the main sources of PAHs in the environment are the incomplete combustion of fossil fuels, as well as municipal waste incineration and agricultural non-surface source emissions. In this work, the scope of our attention includes 16 typical PAHs themselves without involving their metabolites and industrial by-products. Exposure of human and animals to PAHs can lead to a variety of adverse effects, including carcinogenicity and teratogenicity, genotoxicity, reproductive- and endocrine-disrupting effects, immunotoxicity and neurotoxicity, the type and severity of which depend on a variety of factors. On the other hand, the regulatory effect of microplastics (MPs) on the bio-toxicity and bioaccumulation capacity of PAHs has now gradually attracted attention. We critically reviewed the adsorption capacity and mechanisms of MPs on PAHs as well as the effects of MPs on PAHs toxicity, thus highlighting the importance of paying attention to the joint bio-toxicity caused by PAHs-MPs interactions. In addition, due to the extensive nature of the common exposure pathway of PAHs and ultraviolet ray, an accurate understanding of biological processes exposed to both PAHs and UV light is necessary to develop effective protective strategies. Finally, based on the above critical review, we highlighted the research gaps and pointed out the priority of further studies.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Animais , Bioacumulação , Monitoramento Ambiental , Humanos , Incineração , Microplásticos , Plásticos , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade
20.
Spectrochim Acta A Mol Biomol Spectrosc ; 252: 119522, 2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33582437

RESUMO

Keemun black tea is classified into 7 grades according to the difference in its quality. The appearance and flavour are crucial indicators of its quality. This research demonstrates a rapid grading method of jointly using near-infrared reflectance spectroscopy (NIRS) and computer vision systems (CVS) to evaluate the flavour and appearance quality of tea. A Bruker MPA Fourier Transform near-infrared spectrometer was used to record the spectrum of samples. A computer vision system was used to capture the image of tea leaves in an unobstructed manner. 80 tea samples for each grade were analyzed. The performance of four NIRS feature extraction methods (principal component analysis, local linear embedding, isometric feature mapping, and convolutional neural network (CNN)) was compared in this study. Histograms of six geometric features (leaf width, leaf length, leaf area, leaf perimeter, aspect ratio, and rectangularity) of different tea samples were used to describe their appearance. A feature-level fusion strategy was used to combine softmax and artificial neural networks (ANN) to classify NIRS and CVS features. The results indicated that for an individual NIRS signal, CNN achieved the highest classification accuracy with the softmax classification model. The histograms of the combined shape features indicated that when the softmax classification model was used, the classification accuracy was also higher than ANN. The fusion of NIRS and CVS features proved to be the optimal combination; the accuracy of calibration, validation and testing sets increased from 99.29%, 96.67% and 98.57% (when the optimal features from a single-sensor were used) to 100.00%, 99.29% and 100.00% (when features from multiple-sensors were used). This study revealed that the combination of NIRS and CVS features can be a useful strategy for classifying black tea samples of different grades.

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