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1.
J Fish Biol ; 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38476052

RESUMO

Senegalese sole, Solea senegalensis, is a flatfish of high commercial value in the world. It has been identified as an interesting and promising species for marine commercial aquaculture diversification in Europe for at least four decades and was introduced to China in 2003. Early ontogenesis from embryo to juvenile stages in S. senegalensis was analysed under controlled laboratory conditions to provide morphological information for aquaculture. From 0 to 59 days post hatching (dph), 10-20 larvae were sampled and measured each day (0-17 dph) or every 2-6 days (17-59 dph). Morphological characteristics from the egg to the juvenile stage were described. The eggs were separate and spherical with multiple oil globules. After 3 dph, the yolk sac was completely absorbed, mouth and anus were open, a swim bladder appeared, and larvae began feeding on rotifers (Brachionus plicatilis). The larvae began metamorphosis as the notochord flexed upward and the left eye migrated upward after 10 dph. The left eye migrated to the dorsal midline at 15 dph. At 19 dph, the left eye was translocated to the right-ocular side, and the juveniles adopted a benthic lifestyle. The swim bladder degenerated, and the juveniles completed metamorphosis at 23 dph. The growth patterns of some parameters (TL, SL, BH, BW) during larval and juvenile development stages were identified. The inflection points, which are slopes of growth changes, were calculated in growth curves. Three inflection points occurring in the growth curves of larvae and juveniles were found to be associated with metamorphosis, weaning, and transitions in feeding habits. The basic information of embryo development and ontogenesis in this study represents a valuable contribution to the S. senegalensis industry, especially in artificial breeding and rearing techniques.

2.
Ying Yong Sheng Tai Xue Bao ; 34(10): 2747-2756, 2023 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-37897282

RESUMO

Ili Valley is an important ecological barrier in western China and an important economic zone of the Belt and Road Initiative. Exploring the driving factors of ecosystem service value (ESV) based on land use change is of great significance for optimizing regional ecological environment and coordinating human-land relationship. Based on three periods of land use data from 2000 to 2020 in Yili Valley, we used ArcGIS 10.8 and Origin to analyze the characteristics of land use change, temporal and spatial variations of ESV, and the synergy and trade-offs of ecosystem services, and explored the driving factors affecting the spatial differentiation of ESV and the interaction among factors by using Geo-Detector. The results showed that land use change in the study area was obvious from 2000 to 2020, with the area of grassland and water area being greatly reduced and the largest increase for the area of construction land. The ESV of grassland and water area and the service function of water resource supply decreased significantly. ESV high value areas were transformed to low value areas. Synergy was the dominant relationship among ecosystem services in the study area, which showed an increasing trend. Elevation was the main driving factor of ESV spatial differentiation in Yili Valley, and the low elevation plain area suitable for human activities on both sides of the basin was the low ESV value area. The interaction between all factors was manifested as enhanced relationship, while the explanatory power of natural factors was higher than that of social and economic factors.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Humanos , China , Abastecimento de Água , Água
3.
Micromachines (Basel) ; 14(6)2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37374700

RESUMO

The three-body coupling grinding mode of a ball ensures the batch diameter variation and batch consistency of precision ball machining based on the principle of ball forming, resulting in a structure that is simply and feasibly controllable. The change in the rotation angle can be jointly determined using the fixed load of the upper grinding disc and the rotation speed coordination of the inner and outer discs of the lower grinding disc. Related to this, the rotation speed is an important index to guarantee grinding uniformity. To ensure the quality of three-body coupling grinding, this study aims to establish the best mathematical control model of the rotation speed curve of the inner and outer discs in the lower grinding disc. Specifically, it includes two aspects. First, the optimization of the rotation speed curve was mainly studied, and the machining process was simulated with three speed curve combinations: 1, 2, and 3. By analyzing the evaluation index of ball grinding uniformity, the results revealed that the third speed curve combination had the best grinding uniformity, and the three speed curve combinations were optimized on the basis of the traditional triangular wave speed curve. Furthermore, the obtained double trapezoidal speed curve combination not only achieved the traditionally verified stability performance but also overcame the shortcomings of the other speed curves. The mathematical model established in this way was equipped with a grinding control system, which improved the fine control ability of the rotation angle state of the ball blank under the three-body coupling grinding mode. It also obtained the best grinding uniformity and sphericity and laid a theoretical foundation for achieving a grinding effect that was close to the ideal circumstance during mass production. Second, via theoretical comparison and analysis, it was determined that the ball shape and sphericity deviation (SPD) were more accurate than the standard deviation (STD) of the two-dimensional trajectory point distribution. The SPD evaluation method was also investigated via the optimization analysis of the rotation speed curve by means of the ADAMAS simulation. The obtained results coincided with the STD evaluation trend, thus laying a preliminary foundation for subsequent applications.

4.
Brain Sci ; 10(2)2020 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-32050462

RESUMO

The maximum eigenvalue of the adjacency matrix (AM) has been supposed to contain rich information about the corresponding network. An experimental study focused on revealing the meaning and application of the maximum eigenvalue is missing. To this end, AM was constructed using mutual information (MI) to determine the functional connectivity with electroencephalogram (EEG) data recorded with a mental fatigue model, and then was converted into both binary and weighted brain functional network (BFN) and corresponding random networks (RNs). Both maximum eigenvalue and corresponding network characters in BFNs and RNs were considered to explore the changes during the formation of mental fatigue. The results indicated that large maximum eigenvalue means more edges in the corresponding network, along with a high degree and a short characteristic path length both in weighted and binary BFNs. Interestingly, the maximum eigenvalue of AM was always a little larger than that of the corresponding random matrix (RM), and had an obvious linearity with the sum of the AM elements, indicating that the maximum eigenvalue can be able to distinguish the network structures which have the same mean degree. What is more, the maximum eigenvalue, which increased with the deepening of mental fatigue, can become a good indicator for mental fatigue estimation.

5.
Neural Plast ; 2019: 1716074, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31885535

RESUMO

Brain functional network has been widely applied to investigate brain function changes among different conditions and proved to be a small-world-like network. But seldom researches explore the effects of mental fatigue on the small-world brain functional network organization. In the present study, 20 healthy individuals were included to do a consecutive mental arithmetic task to induce mental fatigue, and scalp electroencephalogram (EEG) signals were recorded before and after the task. Correlations between all pairs of EEG channels were determined by mutual information (MI). The resulting adjacency matrices were converted into brain functional networks by applying a threshold, and then, the clustering coefficient (C), characteristic path length (L), and corresponding small-world feature were calculated. Through performing analysis of variance (ANOVA) on the mean MI for every EEG rhythm, only the data of α1 rhythm during the task state were emerged for the further explorations of mental fatigue. For a wide range of thresholds, C increased and L and small-world feature decreased with the deepening mental fatigue. The pattern of the small-world characteristic still existed when computed with a constant degree. Our present findings indicated that more functional connectivities were activated at the mental fatigue stage for efficient information transmission and processing, and mental fatigue can be characterized by a reduced small-world network characteristic. Our results provide a new perspective to understand the neural mechanisms of mental fatigue based on complex network theories.


Assuntos
Encéfalo/fisiopatologia , Fadiga Mental/fisiopatologia , Rede Nervosa/fisiopatologia , Adulto , Mapeamento Encefálico , Conectoma , Eletroencefalografia , Humanos , Masculino , Adulto Jovem
6.
Cent Eur J Immunol ; 42(2): 218-222, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28860941

RESUMO

Dengue virus (DENV) and Japanese encephalitis virus (JEV) are two important pathogenic viruses that can cause severe encephalitis, which is accompanied by inflammatory cytokines. However, the inflammatory cytokine content of cerebrospinal fluid (CSF) in DENV and JEV infection of central nervous system are not sufficiently studied. To investigate cytokine levels in serum and CSF of hospitalised children with DENV and JEV infection of the central nervous system, a total of 183 hospitalised children with viral encephalitis-like syndrome were enrolled between May 2014 and April 2015 at the Children's Hospital of Chenzhou, Hunan, China. DENV and JEV infection was diagnosed by ELISA. Cytokine levels in the serum and CSF were measured by commercial ELISA kits. Twenty-nine (15.85%) and 26 (14.21%) DENV and JEV infections were detected in 183 patients with viral encephalitis-like syndrome, respectively. Higher granulocyte-macrophage colony-stimulating factor (GM-CSF) levels were detected in the serum of JEV infected patients than in DNEV patients (p < 0.05) or in healthy controls (p < 0.001), and levels of GM-CSF, interleukin 6 (IL-6) and monocyte chemoattractant protein-1 (MCP-1) were higher in the CSF than serum in both DENV and JEV infection. Both DENV and JEV infection induced similar cytokine accumulation profiles in the CSF, which probably contributed to DENV- and JEV-induced immunopathogenesis.

7.
Intervirology ; 59(3): 163-169, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28103598

RESUMO

BACKGROUND/AIMS: Coronavirus (CoV) infections induce respiratory tract illnesses and central nervous system (CNS) diseases. We aimed to explore the cytokine expression profiles in hospitalized children with CoV-CNS and CoV-respiratory tract infections. METHODS: A total of 183 and 236 hospitalized children with acute encephalitis-like syndrome and respiratory tract infection, respectively, were screened for anti-CoV IgM antibodies. The expression profiles of multiple cytokines were determined in CoV-positive patients. RESULTS: Anti-CoV IgM antibodies were detected in 22/183 (12.02%) and 26/236 (11.02%) patients with acute encephalitis-like syndrome and respiratory tract infection, respectively. Cytokine analysis revealed that the level of serum granulocyte colony-stimulating factor (G-CSF) was significantly higher in both CoV-CNS and CoV-respiratory tract infection compared with healthy controls. Additionally, the serum level of granulocyte macrophage colony-stimulating factor (GM-CSF) was significantly higher in CoV-CNS infection than in CoV-respiratory tract infection. In patients with CoV-CNS infection, the levels of IL-6, IL-8, MCP-1, and GM-CSF were significantly higher in their cerebrospinal fluid samples than in matched serum samples. CONCLUSION: To the best of our knowledge, this is the first report showing a high incidence of CoV infection in hospitalized children, especially with CNS illness. The characteristic cytokine expression profiles in CoV infection indicate the importance of host immune response in disease progression.


Assuntos
Viroses do Sistema Nervoso Central/epidemiologia , Infecções por Coronavirus/epidemiologia , Citocinas/sangue , Citocinas/líquido cefalorraquidiano , Infecções Respiratórias/epidemiologia , Adolescente , Viroses do Sistema Nervoso Central/diagnóstico , Viroses do Sistema Nervoso Central/imunologia , Quimiocina CCL2/sangue , Quimiocina CCL2/líquido cefalorraquidiano , Criança , Criança Hospitalizada , Pré-Escolar , China/epidemiologia , Coronavirus/imunologia , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/imunologia , Citocinas/imunologia , Progressão da Doença , Feminino , Fator Estimulador de Colônias de Granulócitos/sangue , Fator Estimulador de Colônias de Granulócitos/líquido cefalorraquidiano , Fator Estimulador de Colônias de Granulócitos e Macrófagos/sangue , Fator Estimulador de Colônias de Granulócitos e Macrófagos/líquido cefalorraquidiano , Humanos , Imunoglobulina M/sangue , Imunoglobulina M/líquido cefalorraquidiano , Lactente , Interleucina-6/sangue , Interleucina-6/líquido cefalorraquidiano , Interleucina-8/sangue , Interleucina-8/líquido cefalorraquidiano , Masculino , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/imunologia
8.
Sci Rep ; 5: 9700, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26814847

RESUMO

Tripterygium wilfordii Hook F. (TwHF) based therapy has been proved as effective in treating rheumatoid arthritis (RA), yet the predictors to its response remains unclear. A two-stage trial was designed to identify and verify the baseline symptomatic predictors of this therapy. 167 patients with active RA were enrolled with a 24-week TwHF based therapy treatment and the symptomatic predictors were identified in an open trial; then in a randomized clinical trial (RCT) for verification, 218 RA patients were enrolled and classified into predictor positive (P+) and predictor negative (P-) group, and were randomly assigned to accept the TwHF based therapy and Methotrexate and Sulfasalazine combination therapy (M) for 24 weeks, respectively. Five predictors were identified (diuresis, excessive sweating, night sweats for positive; and yellow tongue-coating, thermalgia in the joints for negative). In the RCT, The ACR 20 responses were 82.61% in TwHF/P+ group, significantly higher than that in TwHF/P- group (P = 0.0001) and in M&S/P+ group (P < 0.05), but not higher than in M&S/P- group. Similar results were yielded in ACR 50 yet not in ACR 70 response. No significant differences were detected in safety profiles among groups. The identified predictors enable the TwHF based therapy more efficiently in treating RA subpopulations.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Tripterygium/química , Adulto , Idoso , Antirreumáticos/farmacologia , Comorbidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Extratos Vegetais/farmacologia , Prognóstico , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
9.
Di Yi Jun Yi Da Xue Xue Bao ; 22(4): 341-3, 2002 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-12390741

RESUMO

OBJECTIVE: To explore the relationship between portal vein hemodynamics and the severity of fibrosis in patients with chronic hepatitis. METHODS: Portal vein blood flow velocity (PBFVe) and volume (PBFVo) along with the serum fibrosis markers were examined in 71 patients with chronic viral hepatitis B, and hepatic pathological changes were routinely observed. RESULTS: As the hepatitis progressed, the PBFVe decreased in close inverse relation to the degree of liver fibrosis (P<0.01) and the levels of the serum fibrosis markers hyaluronic (HA) and collagen IV (IV-C). The PBFVo, however, was not related with the fibrotic status in the patients, but was reduced as the hepatic inflammatory reaction escalated. CONCLUSION: PBFVe is a more sensitive indicator for assessing portal hemodynamics than PBFVo in chronic hepatitis progression, and when combined with serum HA and IV-C levels, it may demonstrate the severity of hepatic fibrosis. PBFVo together with procollagen III level, however, can be meaningful for deciding the intrahepatic inflammation activity.


Assuntos
Hepatite B/complicações , Cirrose Hepática/etiologia , Adolescente , Adulto , Biomarcadores/sangue , Velocidade do Fluxo Sanguíneo , Volume Sanguíneo , Doença Crônica , Feminino , Hepatite B/sangue , Humanos , Cirrose Hepática/sangue , Masculino , Pessoa de Meia-Idade , Veia Porta/fisiopatologia
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