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1.
PeerJ Comput Sci ; 10: e1911, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38435617

RESUMO

The development of cross-border e-commerce logistics services has injected new vitality into the development of international trade, and therefore has become a new hot spot in theoretical research. In order to ensure the healthy development of cross-border e-commerce, it is urgent to build a set of scientific and effective evaluation mechanisms to scientifically evaluate the logistics service quality of cross-border e-commerce. Multi-angle perceptual convolutional neural network is a framework for service scene identification of cross-border e-commerce logistics enterprises based on deep convolutional neural network and multi-angle perceptual width learning. In this article, both shallow features and deep features were input into the deep perception model (DPM) to obtain a set of distinguishable features with causal structure, which was used to completely describe the high-level semantic information of cross-border e-commerce logistics enterprise services. Among them, DPM mainly adopts the fusion strategy of shallow feature and deep feature. Meanwhile, the feature representation is input into the width learning pattern recognition system for training and classification, so as to evaluate the service quality of cross-border e-commerce logistics enterprises. The multi-angle perceptual convolutional neural network can effectively solve the problems of high similarity between service classes of cross-border e-commerce logistics enterprises and large differences within the class, and achieve better generalization performance and algorithm complexity than support vector machine, random forest and convolutional neural network.

2.
Ying Yong Sheng Tai Xue Bao ; 34(9): 2330-2336, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37899097

RESUMO

To investigate the responses of resin canal area of Pinus tabuliformis with different ages to climate change, we analyzed the relationship between the resin canal area and climate factors from 1972 to 2017 in P. tabuliformis plantation at young age, middle age, near-mature, mature, and over-mature periods in Taiyue Mountains, Shanxi Province. The results showed that 55.7% to 75.2% of resin canal occurred in earlywood. The mature and over-mature periods had the largest resin channel area, sequentially followed by near mature, middle age, and young age periods. Annual mean latewood resin canal area increased significantly in near-mature period and mature period, but not in other periods. There was a significant negative correlation between earlywood resin canal area and minimum temperature during the growing season (May to July) for trees at middle age period. Earlywood resin canal area of mature trees showed significant negative correlation with minimum temperature during the growing season, but significant positive correlation with drought (PDSI) in the non-growing season (previous September to current April). The total area of earlywood resin canal at the young, near-mature, and mature periods was less influenced by climate than other periods. The minimum growing season temperature was a limiting factor to earlywood resin canal growth, while the non-growing season drought gradually became a limiting factor for earlywood resin canal with increasing tree age. The total area of earlywood resin canal decreased with increasing non-growing season drought and increasing growing season minimum temperature. In the context of global warming, the earlywood resin canal area may gradually decrease at all five periods, and the most reduction in the over-mature stage.


Assuntos
Mudança Climática , Pinus , Aquecimento Global , China , Secas , Árvores
3.
Ying Yong Sheng Tai Xue Bao ; 34(7): 1779-1786, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37694461

RESUMO

To understand the responses of radial growth to climatic factors and the differences in ecological resilience to drought between a heliophilous species Larix principis-rupprechtii and a shade species Picea meyeri in mixed forests, we developed the tree-ring width chronologies of L. principis-rupprechtii and P. meyeri in three mixed forests based on the samples collected from Toudaogou of Saihanba in Hebei, Ningwu County and Kelan County in Shanxi Province. We analyzed the correlation between climatic factors and various chronologies and examined the differences in resistance (Rc), recovery (Rt), and resilience (Rs) of L. principis-rupprechtii and P. meyeri in response to drought stress. The results showed that the radial growth of L. principis-rupprechtii and P. meyeri was negatively correlated with the mean and maximum air temperature from May to July in three mixed forests, and was positively correlated with the Palmer drought index (PDSI) from May to September. Radial growth decline in trees due to drought stress was significantly different between the two species among the three sites, indicating different physiological and ecological regulation strategies. The resistance of P. meyeri was stronger than that of L. principis-rupprechtii at the three study sites, with stronger resilience and resilient elasticity of L. principis-rupprechtii than P. meyeri. As a result, P. meyeri exhibited greater drought resistance than L. principis-rupprechtii. Under global warming condition, L. principis-rupprechtii might be at greater risk of growth decline than P. meyeri in this region.


Assuntos
Larix , Picea , Secas , Resistência à Seca , Florestas , Árvores
4.
Front Physiol ; 13: 994076, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36213228

RESUMO

Patellofemoral disorders are more common in female runners compared to their male counterparts. Differences in biomechanical characteristics between groups of runners could provide insight into the causes of higher rates of injury in female versus male runners, which would be useful to physical therapists and athletic trainers in development of individualized injury prevention programs. This review compares the differences in biomechanical characteristics between female and male runners. Electronic databases, including PubMed, Scopus, Web of Science, and Embase were searched in December 2021 for studies evaluating sex-specific differences in lower limb mechanics of healthy participants during running. Two independent reviewers determined the inclusion and quality of each research paper. Meta-analyses were used where possible. A total of 13 studies were selected. Means and standard deviations of reported data were retrieved from each selected paper for comparison of results. Three biomechanical variables, including dynamics, muscle activation, and kinematics, were compared between female and male runners. However, no differences were found in kinetic variables or muscle activation between groups due to insufficient data available from the selected studies. Meta-analyses of kinematic variables revealed that female runners exhibited significantly greater hip flexion angle, hip adduction angle, and hip internal rotation angle, but smaller knee flexion angle compared to male runners during running. We found significant differences in kinematic variables between female and male runners, which could influence the training advice of physical therapists and athletic trainers who work with runners, and inform the development of injury prevention programs.

5.
Healthcare (Basel) ; 11(1)2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36611559

RESUMO

(1) Background and purpose: Muscular control and motor function in a patient with Patellofemoral pain syndrome (PFPS) have not yet been investigated systematically. Therefore, this review synthesis the previous results about the association of PFPS with gluteus muscle activation, hip strength, and kinematic characteristic of the hip and knee joint, to deepen understanding of the PFPS etiology and promote the establishment of an effective treatment strategy. (2) Methods: A literature search was conducted from January 2000 to July 2022 in four electronic databases: Medline, Embase, Google scholar, and Scopus. A total of 846 articles were initially identified, and after the screening process based on the inclusion criteria, 12 articles were eventually included. Means and SDs of gluteus medius (GMed), gluteus maximus (GMax), hip strength, and kinematic variation of hip and knee were retrieved from the present study. (3) Results and conclusion: Regarding kinematic variation, moderate evidence indicates that an increased peak hip adduction was found in PFPS groups during running and single leg (SL) squat activities. There is no difference in the GMed and GMax activation levels between the two groups among the vast majority of functional activities. Most importantly, strong evidence suggests that hip strength is weaker in individuals with PFPS, showing less strength of hip external rotation and hip abduction compared to the control group. However, without prospective studies, it is difficult to determine whether hip strength weakness is a cause or a result of PFPS. Therefore, further research is needed to evaluate the hip strength level in identifying individuals most likely to associated with PFPS development is needed.

6.
Medicine (Baltimore) ; 100(7): e24874, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33607863

RESUMO

BACKGROUND: Competition anxiety is also known as pre-competition anxiety (PCA), because this anxiety state often occurs before the athletes face the competition. If it is not adjusted in time, which will greatly affect the performance of athletes, even the mental health and physical health of athletes. Therefore, the selection of appropriate methods to intervene the athletes, reducing the PCA of athletes, and it has an important effect on the competition performance of athletes. Therefore, based on the basic theory of traditional Chinese medicine and sports psychology principles, this study adopts a way of systematic evaluation to study the effect of health-care Qigong Baduanjin (HCQB) combined with auricular point sticking (APS)in the treatment of athletes' PCA (APA), the purpose is to help the majority of athletes to eliminate the PCA. METHODS: Two searchers independently retrieve CNKI, WANFANG databases, VIP, CBM, Web of Science, Embase, PubMed, The Cochran Library and other Chinese and English databases. It is supplemented by manual retrieval to comprehensively collect the relevant literature data of the clinical controlled study of HCQB combined with APS in the treatment of APA. The retrieval time is from January 1, 1990 to October 1, 2020, using the subject word and keywords to retrieve, developing a retrieval style according to the characteristics of the database. The two evaluators independently use the above-mentioned retrieval methods to retrieve the main literature database, summarizing and removing the duplicate literature, then reading the title and abstract of the literature separately, excluding the literature that clearly does not meet the inclusion criteria, and finally reading the literature, and finally including the literature in line with the study, in case of disagreement, with the third researcher to decide. The quality evaluation of the literature is independently evaluated using the bias risk assessment criteria for randomized controlled trials in Cochrane Manual 5.1.0. Using the RevMan 5.3 software for meta-analysis. RESULTS: This study will study the effect of HCQB combined with APS on reducing APA, and the results of the study will be published in high-impact academic journals. CONCLUSION: The quality of athletes' mental state is related to whether athletes can play their true level of sports in the competition, and good mental state is also the prerequisite to ensure that athletes get better results. The conclusions reached by this study will provide quantifiable reference for coaches and athletes, with the aim of providing theoretical basis for helping the athletes eliminate PCA. ETHICS AND DISSEMINATION: The type of this study belongs to the category of systematic evaluation, the data in this study are derived from published research papers and public data in the Internet, so ethical review is not suitable for this study. PROSPERO REGISTRATION NUMBER: 2021 CRD42021228254.


Assuntos
Transtornos de Ansiedade/terapia , Atletas/psicologia , Medicina Tradicional Chinesa/métodos , Qigong/métodos , Pontos de Acupuntura , Transtornos de Ansiedade/prevenção & controle , Terapia Combinada/métodos , Gerenciamento de Dados , Feminino , Humanos , Masculino , Medicina Tradicional Chinesa/efeitos adversos , Qigong/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Metanálise como Assunto
7.
Exp Ther Med ; 11(5): 1581-1586, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27168776

RESUMO

The present study aimed to investigate the association between endothelial progenitor cells (EPCs) and peptic ulcers in patients with or without type 2 diabetes mellitus (T2DM), in association with the efficiency of peptic ulcer treatment. The study recruited healthy subjects and peptic ulcer patients with or without T2DM. All the ulcer patients, including those with and without T2DM, were administered omeprazole for 8 weeks. Peptic ulcer patients with T2DM were additionally treated with glipizide and novolin. Blood samples were then obtained from the three groups following ulcer treatment. CD133+ cells were isolated from the blood samples using magnetic bead selection, and cultured in complete medium 199. Morphological and quantity changes in EPCs were observed by light and fluorescence microscopy. In addition, flow cytometric analysis was used to quantify the number of vascular endothelial cells. The treatment was partially effective in 7 of the 32 peptic ulcer patients without T2DM and 12 of the 32 peptic ulcer patients with T2DM. However, this treatment was ineffective in 20 of the 32 peptic ulcer patients with T2DM. Notably, 25 peptic ulcer patients without T2DM were defined as completely recovered following treatment. In addition, the number of circulating EPCs as well as their colony forming ability was significantly reduced (P<0.05) in the peptic ulcer patients with T2DM following ulcer treatment, compared with the other groups. Circulating EPC counts were significantly increased in peptic ulcer patients without T2DM, as compared with the healthy controls. With regards to colony formation, peptic ulcer patients without T2DM did not exhibit improved colony formation ability. In conclusion, the number of circulating EPCs and their colony-forming ability was significantly reduced in peptic ulcer patients with T2DM following ulcer treatment when compared with the other groups. This suggests that the poor curative effect of peptic ulcer treatment in these patients is associated with impairment of EPCs.

8.
Colloids Surf B Biointerfaces ; 48(1): 17-23, 2006 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-16466909

RESUMO

The electrochemical behaviors of adrenaline at the acetylene black electrode in the presence of sodium dodecyl sulfate (SDS) were investigated by cyclic voltammetry and electrochemical impedance spectroscopy (EIS). The results indicated that the electrochemical responses of adrenaline were apparently improved by SDS, due to the enhanced accumulation of protonated adrenaline via electrostatic interaction with negatively charged SDS at the hydrophobic electrode surface. This was verified by the influences of different kinds of surfactants on the electrochemical signals of adrenaline. The electrochemical parameters of the adrenaline oxidation were explored by chronocoulometry. Under optimal working conditions, the oxidation peak current at 0.57 V was proportional to adrenaline concentration in the range of 5.0x10(-8) to 7.0x10(-6) mol/L, with a low detection limit of 1.0x10(-8)mol/L for 70s accumulation by differential pulse voltammetry (DPV). This method was applied to determine adrenaline in the hydrochloride injection sample. The results are satisfying compared with that by the standardized method of high performance liquid chromatography (HPLC).


Assuntos
Acetileno/química , Eletroquímica/métodos , Epinefrina/química , Dodecilsulfato de Sódio/química , Tensoativos/química , Calibragem , Eletroquímica/instrumentação , Eletrodos , Concentração de Íons de Hidrogênio , Modelos Lineares , Oxirredução , Reprodutibilidade dos Testes , Eletricidade Estática
9.
Ai Zheng ; 24(6): 695-8, 2005 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-15946481

RESUMO

BACKGROUND & OBJECTIVE: Cyclins overexpress in various tumors, but its expression in hepatocellular carcinoma (HCC) and its correlation to cell proliferation and apoptosis are unclear. This study was to determine the expression of Cyclins, proliferating cell nuclear antigen (PCNA), and cell apoptosis in HCC, and to analyze their interrelations. METHODS: Tissue microarray technology and SP immunohistochemistry were used to detect expressions of Cyclins A, B1, D1, E, and PCNA in 122 specimens of HCC. In situ terminal deoxyribonucleotide transferase labeling was used to detect cell apoptosis. RESULTS: In the 122 HCC specimens, positive rate of Cyclin A was 50.0%, of Cyclin B1 was 47.5%, of Cyclin D1 was 42.6%, of Cyclin E was 35.2%. Cyclins levels were significantly higher in HCC tissues of grade II, III, and IV than in HCC tissues of grade I(P 0.05). Densities of apoptotic cells were significantly lower in HCC tissues of grade II, III, and IV than in HCC tissues of grade I(P 0.05); PCNA scores were significantly higher in HCC tissues of grade II, III, and IV than in HCC tissues of grade I(P 0.01). The poorer differentiation, the lower density of apoptotic cells in HCC, the higher PCNA score in HCC. Cyclins levels were negatively related to density of apoptotic cells (r=-0.686, P < 0.01), and positively related to PCNA score (r=0.599, P < 0.01); density of apoptotic cells was negatively related to PCNA score (r=-0.701, P < 0.01). CONCLUSION: Cyclins overexpress in HCC, which may shorten tumor cell cycle phase, accelerate cell proliferation and decrease apoptosis, and result in increased malignant phenotypes.


Assuntos
Apoptose , Carcinoma Hepatocelular/metabolismo , Ciclinas/metabolismo , Neoplasias Hepáticas/metabolismo , Fígado/metabolismo , Adulto , Idoso , Carcinoma Hepatocelular/patologia , Ciclo Celular , Proliferação de Células , Ciclina A/metabolismo , Ciclina B/metabolismo , Ciclina B1 , Ciclina D1/metabolismo , Ciclina E/metabolismo , Feminino , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Antígeno Nuclear de Célula em Proliferação/metabolismo
10.
World J Gastroenterol ; 11(41): 6521-4, 2005 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-16425427

RESUMO

AIM: To investigate the relationship between infiltrating inflammatory cell and tumor angiogenesis in hepatocellular carcinoma (HCC) tissues and their clinicopathological features. METHODS: The paraffin-embedded specimens from 70 cases with HCC were stained using EliVision immunohistochemistry with mAbs against CD68, tryptase, and CD34. The counts of tumor-associated macrophage (TAM), mast cell (MC) and tumor microvessel (MV) were performed in the tissue sections. RESULTS: The mean counts of TAM, MC, and MV in HCC tissues were significantly higher than those in pericarcinomatous liver tissues (TAM: 69.31+/-11.58 vs 40.23+/-10.36; MC:16.74+/-5.67 vs 7.59+/-4.18; MV: 70.11+/-12.45 vs 38.52+/-11.16, P<0.01). The MV count in the patients with metastasis was markedly higher than that with non-metastasis (P<0.01). In addition, the MC count in the patients with poorly differentiated HCC was obviously higher than that with well differentiated HCC (P<0.01). The correlation analysis showed that the TAM count was significantly correlated with the count of MV (r=0.712, P<0.01), and the MC count was obviously correlated with the MV count (r=0.336, P<0.05). CONCLUSION: TAM and MC might be closely related to the enhancement of tumor angiogenesis. The MV count might be associated with tumor invasion and metastasis. Moreover, the MC count might be associated with tumor differentiation and prognosis of HCC.


Assuntos
Carcinoma Hepatocelular/irrigação sanguínea , Carcinoma Hepatocelular/imunologia , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/imunologia , Neovascularização Patológica/imunologia , Adulto , Idoso , Carcinoma Hepatocelular/patologia , Feminino , Humanos , Neoplasias Hepáticas/patologia , Macrófagos/patologia , Masculino , Mastócitos/patologia , Pessoa de Meia-Idade , Neovascularização Patológica/patologia
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