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1.
Sci Rep ; 12(1): 15349, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36097031

RESUMO

Electro-hydraulic shaking table is an essential experimental apparatus to evaluate structural performance under actual vibration condition. The control-structure interaction (CSI) between shaking table and eccentric load has lately received considerable attention for causing the accuracy degradation of shaking table test. At present, the research gap of the influence of the eccentricity of load on the CSI makes it challenging to find the CSI effects. And an effect assessment is yet to be proposed to evaluate the CSI effects, which has impeded the development of test technology. To overcome those theoretical bottlenecks, in this research, an analytical transfer function matrix of shaking table and eccentric load is established to analyze the CSI effects. The analysis is conducted under such conditions as different mass ratio (MR), moment of inertia ratio (IR), and eccentric distance ratio (ER) conditions. Through the analysis, the role of the ER is identified, the sensitivities of the MR, IR, and ER to the transfer function matrix are revealed, and the CSI effects are found. Furthermore, a novelty effect assessment is proposed to appraise whether the CSI effects can be ignored in shaking table test. And the visualization expression of the effect assessment is obtained for convenient application.

2.
Front Nutr ; 8: 735742, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34765630

RESUMO

Radix paeoniae alba (RPA) is a kind of herbal medicine of traditional Chinese medicine (TCM) that is widely used for the treatment of liver diseases and rheumatoid arthritis in clinical practice. As a result of the low extraction efficiency of RPA by the conventional method, many patients are given high dosages. In this study, four exposure doses of dielectric barrier discharge (DBD) plasma (0, 60, 120, and 180 s) were applied to modify the extraction efficiency of paeoniflorin, benzoylpaeoniflorin, tannic acid, gallic acid, 2'-hydroxy-4'-methoxyacetophenone, and polysaccharide in RPA. Finally, the application of plasma for 180 s exhibited a 24.6% and 12.0% (p < 0.001) increase of tannic acid and polysaccharide contents, however, a 2.1% (p < 0.05) and 5.4% (p < 0.001) reduction of paeoniflorin and gallic acid composition, respectively, and no significant difference (p > 0.05) in results obtained from benzoylpaeoniflorin and 2'-hydroxy-4'-methoxyacetophenone contents. Our results of scanning electron microscopy (SEM), automatic specific surface area and pore analyzer, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and thermal gravimetric analysis (TGA) indicated that DBD plasma can etch the surface and undergo graft polymerization by reactive species thereby changing the water/oil holding capacity and eventually changing the extraction efficiency of bioactive compounds in RPA. Overall, our observations provide a scientific foundation for modifying the extraction efficiency of bioactive ingredients related to the pharmacological activities of RPA.

4.
PLoS One ; 15(12): e0243979, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33320914

RESUMO

The Multi-Transmitting Formula (MTF) proposed by Liao et al. is a local artificial boundary condition widely used in numerical simulations of wave propagation in an infinite medium, while the drift instability is usually caused in its numerical implementation. In view of a physical interpretation of the Gustafsson, Kreiss and Sundström criterion on numerical solutions of initial-boundary value problems in the hyperbolic partial differential equations, the mechanism of the drift instability of MTF was discussed, and a simple measure for eliminating the drift instability was proposed by introducing a modified operator into the MTF. Based on the theory of spherical wave propagation and damping effect of medium, the physical implication on modified operator was interpreted. And the effect of the modified operator on the reflection coefficient of MTF was discussed. Finally, the validity of the proposed stable implementation measure was verified by numerical tests of wave source problem and scattering problem.


Assuntos
Fenômenos Geológicos , Modelos Teóricos , Movimento (Física)
5.
World J Gastroenterol ; 26(28): 4170-4181, 2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32821078

RESUMO

BACKGROUND: Recent research suggests that although prokinetic agents, acid suppressors, and radical treatment for Helicobacter pylori infection may be effective in patients with functional dyspepsia (FD), a large proportion of patients still fail to respond to these treatments or may suffer from severe adverse reactions. Many traditional Chinese medicinal herbs can regulate the status of the entire body and have special advantages in the treatment of functional diseases. The present study was designed to verify the efficacy of Biling Weitong Granules (BLWTG), a traditional Chinese medicinal herbal compound formula, in alleviating epigastric pain syndrome (EPS) in FD patients, in an attempt to provide an effective prescription for the clinical treatment of this disease. AIM: To evaluate the clinical efficacy and safety of BLWTG in treating EPS in patients with FD. METHODS: In this multicenter, stratified, randomized, double-blind, placebo-controlled, parallel group clinical trial, eligible patients were randomized into the BLWTG and placebo groups who were treated for 6 wk. Efficacy indicators including the severity and frequency of EPS and the time to pain resolution and safety indicators including adverse events were observed and compared. RESULTS: The baseline demographic data and clinical characteristics, such as epigastric pain symptoms, pain intensity, and frequency of attacks, were matched between the two groups before randomization. After 6 wk of treatment and after the center effect was eliminated, the epigastric pain was significantly improved in 28.33% and 85.59% of the patients in the placebo and BLWTG groups, respectively (P < 0.05). At 6 wk, the resolution rate of epigastric pain was 15% and 69.49% in the placebo and BLWTG groups, respectively (P < 0.05). The differences of total FD clinical score between these two groups were significant (P < 0.05) at 2, 4, and 6 wk (P < 0.05). The scores of each item and the total score in the Functional Digestive Disorders Quality of Life Questionnaire showed significant differences between the two groups at 6 wk after both the center and interaction effects were eliminated (P < 0.05). There was no significant difference in the incidence of adverse events between the two groups, and no serious adverse event was noted during the observation. CONCLUSION: Compared with placebo, BLWTG markedly improved EPS in FD patients without causing serious adverse reactions.


Assuntos
Dispepsia , Infecções por Helicobacter , Helicobacter pylori , Método Duplo-Cego , Dispepsia/tratamento farmacológico , Humanos , Medicina Tradicional Chinesa , Qualidade de Vida , Resultado do Tratamento
6.
Neural Netw ; 94: 115-124, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28772239

RESUMO

There have been a lot of methods to address the recognition of complete face images. However, in real applications, the images to be recognized are usually incomplete, and it is more difficult to realize such a recognition. In this paper, a novel convolution neural network frame, named a low-rank-recovery network (LRRNet), is proposed to conquer the difficulty effectively inspired by matrix completion and deep learning techniques. The proposed LRRNet first recovers the incomplete face images via an approach of matrix completion with the truncated nuclear norm regularization solution, and then extracts some low-rank parts of the recovered images as the filters. With these filters, some important features are obtained by means of the binaryzation and histogram algorithms. Finally, these features are classified with the classical support vector machines (SVMs). The proposed LRRNet method has high face recognition rate for the heavily corrupted images, especially for the images in the large databases. The proposed LRRNet performs well and efficiently for the images with heavily corrupted, especially in the case of large databases. Extensive experiments on several benchmark databases demonstrate that the proposed LRRNet performs better than some other excellent robust face recognition methods.


Assuntos
Identificação Biométrica/métodos , Aprendizado de Máquina , Redes Neurais de Computação , Reconhecimento Automatizado de Padrão/métodos
7.
Med Biol Eng Comput ; 55(8): 1287-1301, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27822698

RESUMO

The detection and classification of white blood cells (WBCs, also known as Leukocytes) is a hot issue because of its important applications in disease diagnosis. Nowadays the morphological analysis of blood cells is operated manually by skilled operators, which results in some drawbacks such as slowness of the analysis, a non-standard accuracy, and the dependence on the operator's skills. Although there have been many papers studying the detection of WBCs or classification of WBCs independently, few papers consider them together. This paper proposes an automatic detection and classification system for WBCs from peripheral blood images. It firstly proposes an algorithm to detect WBCs from the microscope images based on the simple relation of colors R, B and morphological operation. Then a granularity feature (pairwise rotation invariant co-occurrence local binary pattern, PRICoLBP feature) and SVM are applied to classify eosinophil and basophil from other WBCs firstly. Lastly, convolution neural networks are used to extract features in high level from WBCs automatically, and a random forest is applied to these features to recognize the other three kinds of WBCs: neutrophil, monocyte and lymphocyte. Some detection experiments on Cellavison database and ALL-IDB database show that our proposed detection method has better effect almost than iterative threshold method with less cost time, and some classification experiments show that our proposed classification method has better accuracy almost than some other methods.


Assuntos
Interpretação de Imagem Assistida por Computador/métodos , Leucócitos/patologia , Microscopia/métodos , Redes Neurais de Computação , Reconhecimento Automatizado de Padrão/métodos , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Algoritmos , Células Cultivadas , Humanos , Aprendizado de Máquina , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
8.
Neural Netw ; 85: 10-20, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27814461

RESUMO

Recovering the low-rank, sparse components of a given matrix is a challenging problem that arises in many real applications. Existing traditional approaches aimed at solving this problem are usually recast as a general approximation problem of a low-rank matrix. These approaches are based on the nuclear norm of the matrix, and thus in practice the rank may not be well approximated. This paper presents a new approach to solve this problem that is based on a new norm of a matrix, called the truncated nuclear norm (TNN). An efficient iterative scheme developed under the linearized alternating direction method multiple framework is proposed, where two novel iterative algorithms are designed to recover the sparse and low-rank components of matrix. More importantly, the convergence of the linearized alternating direction method multiple on our matrix recovering model is discussed and proved mathematically. To validate the effectiveness of the proposed methods, a series of comparative trials are performed on a variety of synthetic data sets. More specifically, the new methods are used to deal with problems associated with background subtraction (foreground object detection), and removing shadows and peculiarities from images of faces. Our experimental results illustrate that our new frameworks are more effective and accurate when compared with other methods.


Assuntos
Algoritmos , Redes Neurais de Computação
9.
PLoS One ; 10(7): e0128746, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26133984

RESUMO

OBJECTIVE: To conduct an analysis of the frequency of unhealthy food advertising on mainland Chinese television (TV) and children and adolescents' risk of exposure to them. METHODS: The frequencies of all types of advertisements (ads) on forty TV channels in mainland China, the exact ad broadcast times, and the name and brand of all snacks and western fast foods advertised were recorded from 0800 hours to 2400 hours on both a weekday and a weekend day in a week. The difference in the frequencies of the diverse types of ads over eight time intervals (each time interval was 2 hours) were compared, and the trends in ad frequencies during the time intervals were described. RESULTS: The TV channels broadcast 155 (91-183) (expressed as median [P25-P75]) food ads, 87 (38-123) snack ads, 49 (11-85) beverage ads, and 58 (25-76) ads of snacks suitable for limited consumption (SSLCs) in a day. The proportion of snack ads among food ads (SPF%) was 55.5% (40.3%-71.0%), and the proportion of SSLC ads among snack ads (LPS%) was 67.4% (55.4%-79.3%). The ad frequencies for food, snacks, SSLCs, and beverages demonstrated significant differences among the eight time intervals (all P=0.000). TV channels broadcast the most frequent ads for food, snacks, SSLCs, and beverages during the time interval from 2000 hours to 2200 hours among the eight time intervals. CONCLUSIONS: Chinese children and adolescents may be at a high risk of exposure to unhealthy food advertising on TV. Reducing the exposure risk strongly requires multisectoral cooperation.


Assuntos
Publicidade/estatística & dados numéricos , Fast Foods/economia , Indústria Alimentícia/ética , Lanches/ética , Adolescente , Publicidade/economia , Criança , China , Fast Foods/provisão & distribuição , Feminino , Indústria Alimentícia/economia , Humanos , Masculino , Marketing/estatística & dados numéricos , Marketing/tendências , Risco , Televisão/economia , Televisão/tendências
10.
Public Health Nutr ; 17(3): 519-28, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23369241

RESUMO

OBJECTIVE: To develop a new model of desirable dietary pattern (N-DDP) score for Chinese diets and to validate it against the nutrient-rich foods (NRF) index. DESIGN: The N-DDP score model followed the principles of the traditional DDP (T-DDP) score model (DDP-China for 2000) proposed in 1991 and of food grouping in the dietary pagoda for Chinese residents in 2007, and made detailed ratings by expressing the food weight coefficient, reasonable maximum limit of the score and an algorithm of the deserved score for each group of foods after considering current nutritional problems of Chinese residents. The N-DDP score model was validated against the NRF9·3 index with linear regression analysis and compared with the T-DDP score model. Settings One set of dietary data was extracted from the diet recommended by the dietary pagoda for Chinese residents in 2007 and the literature on dietary surveys in China. The other two sets of dietary data were from a dietary survey in 2011. DDP scores for all three dietary data sets were calculated with the N-DDP score model and the T-DDP score model. SUBJECTS: All items of dietary records in the three dietary data sets were included in the present study. RESULTS: All DDP scores obtained with the N-DDP score model were positively correlated (P = 0·000) with the NRF9·3 index. DDP scores obtained with the N-DDP score model had higher R 2 with the NRF9·3 index than those of the T-DDP score model, as well as higher ß values. CONCLUSIONS: It can be considered that the N-DDP score is a more accurate and convenient tool to evaluate current individual and group diet for Chinese residents.


Assuntos
Registros de Dieta , Dieta/normas , Alimentos/classificação , Avaliação Nutricional , Valor Nutritivo , Algoritmos , China , Ingestão de Energia , Feminino , Alimentos/estatística & dados numéricos , Humanos , Modelos Lineares , Masculino , Análise de Regressão , Reprodutibilidade dos Testes
11.
Artigo em Inglês | MEDLINE | ID: mdl-24058372

RESUMO

Objective. To determine the efficacy and safety of Lingmao Formula combined with entecavir for HBeAg-positive chronic hepatitis B patients with mildly elevated alanine aminotransferase (ALT). Methods. 301 patients were randomly assigned to receive Lingmao Formula combined with entecavir (treatment group) or placebo combined with entecavir (control group) for 52 weeks. The outcomes of interest included the reduction of serum HBV DNA level, HBeAg loss, HBeAg seroconversion, ALT normalization, and histological improvement. Results. The mean decrease of serum HBV DNA level from baseline and the percentage of patients who had reduction in serum HBV DNA level ≥2 lg copies/mL in treatment group were significantly greater than that in control group (5.5 versus 5.4 lg copies/mL, P = 0.010; 98.5% versus 92.6%, P = 0.019). The percentage of HBeAg loss in treatment group was 22.8%, which was much higher than a percentage of 12.6% in control group (P = 0.038). There was no significant difference between the two groups in histological improvement. Safety was similar in the two groups. Conclusions. The combination of Lingmao Formula with entecavir could result in significant decrease of serum HBV DNA and increase of HBeAg loss for HBeAg-positive chronic hepatitis B patients with mildly elevated ALT without any serious adverse events. Clinical trial registration number is ChiCTR-TRC-09000594.

12.
J AOAC Int ; 95(5): 1505-10, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23175986

RESUMO

The objective of this study was to develop a new Tween-80 microbiological assay (Tween-80 MBA) to determine human or animal serum folate levels and to verify its reliability. The effects of the Lactobacillius casei subspecies rhamnosus (L. casei, ATCC No. 7469) inoculum concentration, incubation time, and Tween-80 on L. casei growth were studied, and the serum folate levels were investigated. Serum samples were collected from patients with esophageal cancer (EC) and healthy control subjects in Yanting, healthy adult subjects in Chengdu, Sichuan, and in male Sprague-Dawley rats. Optimal conditions for the new MBA were as follows: 1.28 x 10(7) CFU/mL working inoculum, vitamin folic acid assay broth with 0.24% (w/w) Tween-80, and anaerobic incubation with L. casei at 37 degrees C for 22 h. Under the optimal conditions, the working curve was in simple linear rather than logarithmic equation; the linear working curve of the folic acid standard working solution concentration versus the turbidity (adsorption value) of medium with L. casei ranged from 0.05 to 1.00 microg/L; the linear correlation coefficient was 0.9989 (SD 0.0007); the recovery rate of folate was 105.4-112.7%; and the minimum concentration for detecting folate was 0.03 microg/L. The RSD within-day and between-day precisions were 5.6 and 3.3%, respectively. The serum folate level of 100 EC patients was 6.4 (SEM 0.4) microg/L which was significantly lower than that of healthy control subjects [8.0 (SEM 0.6) microg/L, n = 100, P=0.020]. The new Tween-80 MBA is considered to be a reliable method for measuring serum folate level.


Assuntos
Bioensaio/métodos , Ácido Fólico/sangue , Lacticaseibacillus rhamnosus/metabolismo , Polissorbatos/química , Adolescente , Adulto , Animais , Bioensaio/normas , Feminino , Humanos , Lacticaseibacillus casei/metabolismo , Masculino , Pessoa de Meia-Idade , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Adulto Jovem
13.
Neurol India ; 58(6): 869-74, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21150051

RESUMO

UNLABELLED: background and objectives: Spontaneous vertebral artery dissection (sVAD) is a rare condition and can potentially cause a stroke, particularly in young to middle-aged people. PATIENTS AND METHODS: The clinical manifestations, medical imaging characteristics, treatment, and prognosis of 16 patients with sVAD were analyzed. RESULTS: None of the 16 patients had a history of head or neck trauma. The most common clinical manifestation was headache with symptoms of posterior-circulation ischemia (63%). Diagnosis of VAD was definitive in one patient at autopsy, and in the remaining it was established by magnetic resonance angiography, computer tomography angiography, or digital subtraction angiography. Treatment modalities included: thrombolysis with urokinase (1), antiplatelet therapy (6), and endovascular stenting (9). There was one death and the remaining 15 patients were followed up for 3-48 months and did not have recurrence of cerebral events. CONCLUSIONS: Rapid and accurate diagnosis of sVAD and proper treatment are crucial for good outcomes. This study shows that antiplatelet therapy and endovascular treatment are effective treatments for sVAD.


Assuntos
Dissecação da Artéria Vertebral/diagnóstico , Dissecação da Artéria Vertebral/terapia , Adolescente , Adulto , Feminino , Seguimentos , Humanos , Angiografia por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X/métodos , Adulto Jovem
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