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1.
Materials (Basel) ; 16(8)2023 Apr 18.
Article in English | MEDLINE | ID: mdl-37110029

ABSTRACT

In this paper, a light-controlled variable damping system (LCVDS) is proposed based on PLZT ceramics and electrorheological fluid (ERF). The mathematical models for the photovoltage of PLZT ceramics and the hydrodynamic model for the ERF are established, and the relationship between the pressure difference at both ends of the microchannel and the light intensity is deduced. Then, simulations are conducted by applying different light intensities in the LCVDS to analyze the pressure difference at both ends of the microchannel using COMSOL Multiphysics. The simulation results show that the pressure difference at both ends of the microchannel increases with the increase in light intensity, which is consistent with results from the mathematical model established in this paper. The error rate of the pressure difference at both ends of the microchannel is within 13.8% between the theoretical and simulation results. This investigation lays the foundation for the application of light-controlled variable damping in future engineering.

3.
Sci Rep ; 12(1): 946, 2022 Jan 18.
Article in English | MEDLINE | ID: mdl-35042924

ABSTRACT

For the airborne pod strapdown inertial navigation system, it is necessary to use the host aircraft's inertial navigation system for the transfer alignment as quickly and accurately as possible in the flight process of the aircraft. The purpose of this paper is to propose an adaptive transfer alignment method based on the observability analysis for the strapdown inertial navigation system, which is able to meet the practical need of maintaining the navigation accuracy of the airborne pod. The observability of each state variable is obtained by observability analysis of system state variables. According to the weight of the observability, a transfer alignment filter algorithm based on adaptive adjustment factor is constructed to reduce the influence of weak observability state variables on the whole filter, which can improve the estimation accuracy of transfer alignment. Simulations and experiment tests of the airborne pod and the master strapdown inertial navigation systems show that the adaptive transfer alignment method based on the observability analysis can overcome the shortage of the weak observability state variables, so as to improve the alignment and the navigation performance in practical applications, thus improving the adaptability of the airborne pod.

4.
Mitochondrial DNA B Resour ; 5(1): 1046-1047, 2020 Feb 03.
Article in English | MEDLINE | ID: mdl-33366867

ABSTRACT

Chlorophytum comosum is a perennial ornamental plant in the family Liliaceae, it is also a valuable medicinal plant. To enrich the genetic resources of C. comosum, its chloroplast genome was determined by Illumina sequencing data. The chloroplast genome is a typical quadripartite structure with a size of 153,983 bp, of which the LSC region is 83,471 bp, the SSC region is 18,010 bp, and the pair of IR regions is 26,251 bp. The overall GC content is 37%. It contains 131 genes, including 85 protein-coding genes, 38 tRNA genes, and 8 rRNA genes. Phylogenetic analyses showed that C. comosum is closely related to Chlorophytum rhizopendulum. However, it can be distinguished from other plants. This study enriches the sequence resources of C. comosum and provides important data for the development of molecular identification markers.

5.
J Huazhong Univ Sci Technolog Med Sci ; 35(5): 759-762, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26489635

ABSTRACT

The effect of topical propranolol gel on the levels of plasma renin, angiotensin II (ATII) and vascular endothelial growth factor (VEGF) in superficial infantile hemangiomas (IHs) was investigated. Thirty-three consecutive children with superficial IHs were observed pre-treatment, 1 and 3 months after application of topical propranolol gel for the levels of plasma renin, ATII and VEGF in Department of General Surgery of Dongfang Hospital from February 2013 to February 2014. The plasma results of IHs were compared with those of 30 healthy infants of the same age from out-patient department. The clinical efficiency of topical propranolol gel at 1st, and 3rd month after application was 45%, and 82% respectively. The levels of plasma renin, ATII and VEGF in patients pre-treatment were higher than those in healthy infants (565.86 ± 49.66 vs. 18.19 ± 3.56, 3.20 ± 0.39 vs 0.30 ± 0.03, and 362.16 ± 27.29 vs. 85.63 ± 8.14, P < 0.05). The concentrations of VEGF and renin at 1st and 3rd month after treatment were decreased obviously as compared with those pre-treatment (271.51 ± 18.59 vs. 362.16 ± 27.29, and 405.18 ± 42.52 vs. 565.86 ± 49.66 P < 0.05; 240.80 ± 19.89 vs. 362.16 ± 27.29, and 325.90 ± 35.78 vs. 565.86 ± 49.66, P < 0.05, respectively), but the levels of plasma ATII declined slightly (2.96 ± 0.37 vs. 3.20 ± 0.39, and 2.47 ± 0.27 vs. 3.20 ± 0.39, P > 0.05). It was indicated that the increased renin, ATII and VEGF might play a role in the onset or development of IHs. Propranolol gel may suppress the proliferation of IHs by reducing VEGF.


Subject(s)
Adrenergic beta-Antagonists/therapeutic use , Angiotensin II/blood , Hemangioma, Capillary/drug therapy , Propranolol/therapeutic use , Renin/blood , Skin Neoplasms/drug therapy , Vascular Endothelial Growth Factor A/blood , Administration, Cutaneous , Case-Control Studies , Female , Gels , Hemangioma, Capillary/blood , Hemangioma, Capillary/blood supply , Hemangioma, Capillary/pathology , Humans , Infant , Infant, Newborn , Male , Skin Neoplasms/blood , Skin Neoplasms/blood supply , Skin Neoplasms/pathology , Treatment Outcome
6.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 40(3): 317-25, 2015 Mar.
Article in Chinese | MEDLINE | ID: mdl-25832524

ABSTRACT

OBJECTIVE: To assess the effect of premolar extractions on third molar angulation changes in orthodontic patients. METHODS: The Cochrane library, PubMed, Embase, China Science and Technology Periodical Database, China National Knowledge Infrastructure (CNKI), Chinese Biomedical Literature Database (CBM) and Wanfang database were searched from January 1, 1990 to May 20, 2014 to identify all the studies about third molar angulation changes in orthodontic patients with or without premolars extraction, which was assigned as a extraction group and a control group. Th e extraction group was further divided into a fi rst premolar extraction subgroup and a second premolar extraction subgroup. Literature filtering, data extraction and methodological quality evaluation were finished independently by two researchers. After cross checking, the disagreements were solved by discussion. Meta-analysis was carried out by RevMan 5.3.3 software. RESULTS: Ten studies involving 712 patients were included. Meta-analysis revealed that: compared with the control group, the changes of third molar angulation in maxillary and mandible in the extraction group were statistically significantly different (all P<0.05); the difference in angulation between the two groups was about 5.19° in maxillary and 3.55° in mandibul. As for the premolar extraction subgroups, there was no significant difference in mandibular third molar angulation between them (P>0.05). CONCLUSION: The orthodontic treatment involving first or second premolar extractions can improve the maxillary third molar angulation, and the second premolar extraction is the best option.


Subject(s)
Bicuspid , Molar, Third , Tooth Extraction , Asian People , China , Humans , Mandible , Maxilla
7.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-353168

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the effect of topical propranolol gel on the levels of plasma vascular endothelial growth factor (VEGF), basic fibroblastic growth factor (bFGF) and matrix metalloproteinases-9 (MMP-9) in proliferating infantile hemangiomas (IHs) of superficial type.</p><p><b>METHODS</b>33 consecutive children with superficial IHs were observed pre-treatment, 1 and 3 months after application of topical propranolol gel for the levels of plasma VEGF, MMP-9 and bFGF by enzyme-linked immunosorbent assay (ELISA) in Department of General Surgery of Dongfang Hospital from February 2013 to February 2014. The plasma results of IHs were compared with those of 30 healthy infants. The clinical efficacy in IHs was evaluated by Achauer system. Differences of plasma results between the healthy group and the IHs group pre-treatment were analyzed using Mann-Whitney U-test. Paired sample comparisons of any two time points of pre-treatment, 1 month and 3 months after treatment in IHs were evaluated by Wilcoxon signed-rank test.</p><p><b>RESULTS</b>The clinical efficiency of topical propranolol gel at 1, 3 months after application were 45.45%, 81.82% respectively. The levels of plasma VEGF and MMP-9 in patients pre- treatment were higher than those in healthy infants [(362.16 ± 27.29) pg/ml vs (85.63 ± 8.14) pg/ml, (1376.41 ± 42.15) pg/ml vs (687.27 ± 44.1) pg/ml, P < 0.05], but the level of bFGF did not show significant difference [(176.03 ± 13.60 ) pg/ml vs (235.94 ± 35.43 ) pg/ml, P > 0. 05 ]. The concentrations of VEGF and bFGF at 1, 3 months after treatment decreased obviously [(271.51 ± 18.59) pg/ml vs (362.16 ± 27.29 ) pg/ml, (135.85 ± 12.66) pg/ml vs (176.03 ± 13.60) pg/ml], 1 month after treatment vs pre-treatment, P < 0.05; (240.80 ± 19.89) pg/ml vs (362.16 ± 27.29) pg/ml, (107.31 ± 5.82) pg/ml vs (176.03 ± 13.60) pg/ml, 3 month after treatment vs pre-treatment, P < 0.05, whereas the levels of plasma MMP-9 declined slightly [(1321.18 ± 48.74) pg/ml vs (1376.41 ± 42.15 ) pg/ml, (1468.68 ± 32.78) pg/ml vs (1376.41 ± 42 2.15 ) pg/ml, P > 0.05 ].</p><p><b>CONCLUSIONS</b>Propranolol gel may suppress the proliferation of superficial infantile bemangiomas by reducing VEGF and bFGF.</p>


Subject(s)
Child , Humans , Infant , Administration, Topical , Case-Control Studies , Enzyme-Linked Immunosorbent Assay , Fibroblast Growth Factor 2 , Blood , Gels , Hemangioma , Blood , Drug Therapy , Matrix Metalloproteinase 9 , Blood , Propranolol , Pharmacology , Time Factors , Vascular Endothelial Growth Factor A , Blood
8.
PLoS One ; 8(12): e83011, 2013.
Article in English | MEDLINE | ID: mdl-24376625

ABSTRACT

The dehydration responsive element binding (DREB) transcription factors play an important role in regulating stress-related genes. OsDREB2A, a member of the DREBP subfamily of AP2/ERF transcription factors in rice (Oryza sativa), is involved in the abiotic stress response. OsDREB2A expression is induced by drought, low-temperature and salt stresses. Here, we report the ability of OsDREB2A to regulate high-salt response in transgenic soybean. Overexpressing OsDREB2A in soybeans enhanced salt tolerance by accumulating osmolytes, such as soluble sugars and free proline, and improving the expression levels of some stress-responsive transcription factors and key genes. The phenotypic characterization of transgenic soybean were significantly better than those of wild-type (WT). Electrophoresis mobility shift assay (EMSA) revealed that the OsDREB2A can bind to the DRE core element in vitro. These results indicate that OsDREB2A may participate in abiotic stress by directly binding with DRE element to regulate the expression of downstream genes. Overexpression of OsDREB2A in soybean might be used to improve tolerance to salt stress.


Subject(s)
Gene Expression Regulation, Plant , Glycine max/genetics , Oryza/genetics , Plant Proteins/genetics , Salt Tolerance/genetics , Transcription Factors/genetics , Cold Temperature , Dehydration , Electrophoretic Mobility Shift Assay , Oryza/drug effects , Oryza/metabolism , Plant Proteins/metabolism , Plants, Genetically Modified , Protein Binding , Response Elements , Salinity , Sodium Chloride/pharmacology , Glycine max/drug effects , Glycine max/metabolism , Stress, Physiological/genetics , Transcription Factors/metabolism
9.
PLoS One ; 7(9): e45568, 2012.
Article in English | MEDLINE | ID: mdl-23029105

ABSTRACT

Gibberellic acids (GAs) are plant hormones that play fundamental roles in plant growth and developmental processes. Previous studies have demonstrated that three key enzymes of GA20ox, GA3ox, and GA2ox are involved in GA biosynthesis. In this study, the Arabidopsis DREB1A gene driven by the CaMV 35S promoter was introduced into soybean plants by Agrobacterium- mediated transformation. The results showed that the transgenic soybean plants exhibited a typical phenotype of GA-deficient mutants, such as severe dwarfism, small and dark-green leaves, and late flowering compared to those of the non-transgenic plants. The dwarfism phenotype was rescued by the application of exogenous GA(3) once a week for three weeks with the concentrations of 144 µM or three times in one week with the concentrations of 60 µM. Quantitative RT-PCR analysis revealed that the transcription levels of the GA synthase genes were higher in the transgenic soybean plants than those in controls, whereas GA-deactivated genes except GmGA2ox4 showed lower levels of expression. The transcript level of GmGA2ox4 encoding the only deactivation enzyme using C(20)-GAs as the substrates in soybean was dramatically enhanced in transgenic plants compared to that of wide type. Furthermore, the contents of endogenous bioactive GAs were significantly decreased in transgenic plants than those of wide type. The results suggested that AtDREB1A could cause dwarfism mediated by GA biosynthesis pathway in soybean.


Subject(s)
Arabidopsis Proteins/genetics , Dwarfism/genetics , Gene Expression , Gibberellins/metabolism , Glycine max/genetics , Glycine max/metabolism , Phenotype , Transcription Factors/genetics , Gibberellins/pharmacology , Plant Leaves/anatomy & histology , Plant Leaves/drug effects , Plants, Genetically Modified , Seeds/anatomy & histology , Seeds/drug effects , Glycine max/anatomy & histology , Glycine max/drug effects
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