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2.
Langmuir ; 40(12): 6402-6412, 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38489303

ABSTRACT

A theoretical model was developed to describe the dynamics of a deformable fluid interface interacting with an approaching solid without contact by both the attractive electrostatic and van der Waals (i.e., vdW) interaction, analogous to the situation in the experiments by electric force microscopy (i.e., EFM) or electric-surface force apparatus (i.e., E-SFA) involved in the soft fluid interface. On the basis of this model, a numerical study of the deformation of the fluid interface, the force-vs-separation behavior, and the critical limiting conditions of contact has systematically been carried out. Our results show that the surface pressure induced by the electrostatic interaction plays a more prominent role in the deformation of the fluid interface than the vdW interaction does, and there exists a principal length scale associated with the relative strength of the electrostatic field to the surface tension, affecting the fluid interface shape under the electrostatic field. It was also shown that both the force-distance curves and the corresponding curves of fluid interface deformation peak versus distance for various electrostatic fields satisfy the universal scaling power law. Moreover, an analytical solution to the Euler-Lagrange differential equation governing the deformation of the fluid interface under the external electric field is obtained, and two extended formulas for explicitly describing the principal length scales that respectively characterize the lateral and longitudinal deformations of the fluid interface were determined.

3.
Nanotechnology ; 35(11)2023 Dec 27.
Article in English | MEDLINE | ID: mdl-38064739

ABSTRACT

This research article, explores the influence of an inclined magnetic field on the fluid flow over a permeable stretching/shrinking surface with heat transfer. The study use water as a conventional base fluid, with graphene oxide (GO) and Aluminum oxide (Al2O3) nanoparticles submerged to create a nanofluid, the system of governing nonlinear partial differential equations converted into ordinary differential equations via suitable similarity conversions. This allow for the unique solution for stretching sheet/shrinking sheets to be obtained, along with the corresponding temperature solution in terms of the hypergeometric function, several parameters are included in the investigation and their contribution is graphically explained to examine physical characteristics such as radiation, inclined magnetic field, solution domain, volume fraction parameter, and temperature jump. Increasing the volume fraction and thermal radiation increases the thermal boundary layer, increasing the magnetic field parameter and inverse Darcy number increases the temperature and decays the velocity profile. The present work has many useful applications in engineering, biological and physical sciences, as well as in cleaning engine lubricants and thrust-bearing technologies.

4.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 56(7): 646-651, 2021 Jul 09.
Article in Chinese | MEDLINE | ID: mdl-34275219

ABSTRACT

Objective: To investigate the accuracy of pure titanium and cobalt-chromium alloy frameworks fabricated using the additive manufacturing (AM) of selective laser melting technology (SLM) for the mandibular implant-supported fixed prostheses and the maxillary removable partial denture (RPD), and to provide a reference for clinical application of SLM pure titanium frameworks. Methods: One edentulous mandibular model with implants and screw fixed abutments at bilateral canines and the first molars was selected and used as the mandibular full arch implant-supported model. At the same time, a Kennedy class Ⅰ maxillary dentition defect model was selected. The digital models were obtained by scanning the dental models, and the metal frameworks of the mandibular full arch implant-supported denture and the maxillary RPD (design model) were designed using the 3 Shape software. Meanwhile, 12 mandibular frameworks in the cobalt-chromium alloy and the pure titanium (6 in each group were treated with heat treatment, while the other 6 were not treated), and 7 maxillary frameworks in the cobalt-chromium alloy and the pure titanium were respectively made by SLM with the improved dual-laser metal printer. The axial direction of the printing powder accumulation was taken as the Z-axis. During the design process, the software (3Shape Dental System 2018) automatically generated the X-axis and Y-axis, X axis was the sagittal axis of the dental model and Y axis was the coronal axis of the dental model. The deviation of the interface center of the abutment of the digital model of the mandibular frameworks from the design model in the X, Y and Z axes was analyzed. As for the trueness of the mandibular framework, the larger the deviation data was, the worse the trueness was. The deviation of the whole maxillary framework and 7 measuring points (palatal plate center point and bilateral occlusal rests, I bars, proximal plates) were analyzed. The fitness of the whole maxillary framework to the design model was expressed by root mean square (RMS) of the deviation data, and the fitness of measuring points was expressed by the mean±standard deviation of the data. The trueness differences of each group before and after heat treatment of the mandibular framework and the fitness of the maxillary framework were compared. Results: The cobalt-chromium alloy frameworks showed lower trueness on the X, Y, Z-axes [(96.3±12.1), (86.3±11.4), (61.2±13.2) µm] than did the pure Ti frameworks [(82.3±11.2), (72.2±10.2), (51.2±11.6) µm] by SLM, and the heat treatment could reduce the discrepancy between the SLM frameworks and STL models, for pure titanium frameworks [(62.4±11.3), (55.2±13.2), (41.3±10.8) µm] and for cobalt-chromium alloy [(84.5±10.5), (72.3±11.2), (54.2±11.6) µm]. For the thin RPD major frameworks, pure titanium had better fitness [(121.3±17.0) µm] than cobalt-chromium alloy [(174.0±18.3) µm] by SLM, and the difference was statistically significant (P<0.05). Conclusions: Pure titanium frameworks fabricated by SLM additive manufacturing technology exhibited better fitness and trueness than did the Co-Cr frameworks after heat treatment respectively, and this satisfied the requirements of implant-supported fixed prostheses and RPD major metal frameworks.


Subject(s)
Computer-Aided Design , Titanium , Chromium Alloys , Dental Prosthesis, Implant-Supported , Denture, Complete , Lasers
6.
Int J Immunogenet ; 43(4): 249-50, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27302621

ABSTRACT

A new allele, officially named B*40:01:40, was detected in a Chinese individual by sequence-based typing (SBT). The new allele differs from B*40:01:01 by a single nucleotide exchange at position 99 in codon 9, which results in synonymous substitution and seems not to compromise the HLA complex and T-cell receptor interaction.


Subject(s)
HLA-B Antigens/genetics , HLA-B Antigens/immunology , Alleles , Amino Acid Substitution/genetics , Amino Acid Substitution/immunology , Asian People , China , Codon/genetics , HLA-B Antigens/isolation & purification , Humans , Receptors, Antigen, T-Cell/genetics , Receptors, Antigen, T-Cell/immunology
7.
HLA ; 87(5): 382-3, 2016 May.
Article in English | MEDLINE | ID: mdl-27006006

ABSTRACT

HLA-A*02:513 shows one nucleotide difference with A*02:07:01 (125G > A).


Subject(s)
Alleles , HLA-A Antigens/genetics , Base Sequence , Exons/genetics , Histocompatibility Testing , Humans , Sequence Alignment
8.
HLA ; 87(5): 407-8, 2016 May.
Article in English | MEDLINE | ID: mdl-26969342

ABSTRACT

HLA-DRB1*14:150 shows one nucleotide difference when compared with DRB1*14:54:01 at codon 49 (A > P).


Subject(s)
Alleles , Asian People/genetics , Exons/genetics , HLA-DRB1 Chains/genetics , Base Sequence , Humans , Sequence Alignment
9.
Neuroscience ; 159(2): 727-34, 2009 Mar 17.
Article in English | MEDLINE | ID: mdl-19167463

ABSTRACT

Neuronal nitric oxide synthases (nNOS) is distributed throughout the central nervous system (CNS) and has been proposed to modulate neuronal activity in the nucleus tractus solitarii (NTS). Here, we investigated whether the activation of nNOS is involved in insulin-induced cardiovascular responses in the NTS. Insulin (100 IU/ml) was unilaterally microinjected into the NTS, and the cardiovascular effects were evaluated before and after microinjection of the nNOS inhibitors 7-nitroindazole (7-NI) (5 pmol) and N(5)-(1-imino-3-butenyl)-l-ornithine (vinyl-L-NIO) (600 pmol). Western blot and immunohistochemical analyses were performed to determine nNOS phosphorylation levels after insulin or phosphoinositide 3-kinase (PI3K) inhibitor LY294002 microinjection into the NTS. Unilateral microinjection of insulin into the NTS produced prominent depressor and bradycardic effects in WKY rats. Pretreatment with the nNOS inhibitors 7-NI and Vinyl-L-NIO attenuated the cardiovascular response evoked by insulin in Wistar-Kyoto (WKY) rats. Moreover, Western blot analysis showed a significant increase in nNOS (16.5+/-0.4-fold; P<0.05; n=4) phosphorylation after insulin injection, whereas the PI3K inhibitor LY294002 abolished the insulin-induced effects. In situ nNOS phosphorylation was found to be increased in the NTS after insulin injection. Furthermore, co-immunoprecipitation assay showed Akt and nNOS can bind to each other as detected by phospho-Akt(S473) and phospho-nNOS(S1416) antibodies. In vitro kinase assay showed insulin activated Akt can directly phosphorylate nNOS(S1416). These results demonstrated that nNOS may couple with the activation of the insulin receptor, via the liberation of NO, in order to participate in central cardiovascular regulation of WKY rats.


Subject(s)
Blood Pressure/drug effects , Heart Rate/drug effects , Insulin/pharmacology , Nitric Oxide Synthase Type I/metabolism , Solitary Nucleus/drug effects , Analysis of Variance , Animals , Chromones/pharmacology , Dose-Response Relationship, Drug , Drug Interactions , Enzyme Activation/drug effects , Enzyme Inhibitors/pharmacology , Gene Expression Regulation, Enzymologic/drug effects , Heart Rate/radiation effects , Immunoprecipitation/methods , Indazoles/pharmacology , Male , Microinjections/methods , Morpholines/pharmacology , Ornithine/analogs & derivatives , Ornithine/pharmacology , Rats , Rats, Inbred WKY , Solitary Nucleus/enzymology
10.
J Phys Condens Matter ; 20(11): 114105, 2008 Mar 19.
Article in English | MEDLINE | ID: mdl-21694198

ABSTRACT

A model is presented that describes nonstationary solidification of binary melts or solutions from a cooled boundary maintained at a time-dependent temperature. Heat and mass transfer processes are described on the basis of the principles of a mushy layer, which divides pure solid material and a liquid phase. Nonlinear equations characterizing the dynamics of the phase transition boundaries are deduced. Approximate analytical solutions of the model under consideration are constructed. A method for controlling the external temperature at a cooled wall in order to obtain a required solidification velocity is discussed.

11.
Article in Chinese | MEDLINE | ID: mdl-12024591

ABSTRACT

OBJECTIVE: To study the biocompatibility of skin reproductive membrane. METHODS: According to ISO's standards, the extractions of the skin reproductive membrane were prepared, and the acute systematic toxicity test, primary skin irritant test, cytotoxicity test, gene expression of type I collagen and fibronectin were detected to evaluate the biocompatibility of skin reproductive membrane. RESULTS: All of those tests showed negative results. CONCLUSION: The skin reproductive membrane has excellent biocompatibility in the level of the systematic, cellular and molecular biology.


Subject(s)
Biocompatible Materials , Collagen Type I/biosynthesis , Fibronectins/biosynthesis , Membranes, Artificial , Skin , Animals , Collagen Type I/genetics , Fibronectins/genetics , Mice , Prostheses and Implants , Random Allocation , Skin Tests
12.
Shi Yan Sheng Wu Xue Bao ; 32(4): 373-9, 1999 Dec.
Article in Chinese | MEDLINE | ID: mdl-12548865

ABSTRACT

30 female SD rats (3 months old) are equally divided into three groups: ovariectomy (OVX) rats, sham-operated (SHO) rats and 17 beta estradiol (E2) treated OVX rats. For each group, mRNA was isolated from long bone at one month and three months after surgery, respectively. mRNA was reverse transcribed into single strand cDNA and then used as a probe hybridizing to the DNA fragments of col I alpha(1), col I alpha(2), col III, col V, fibronectin, IL-1, IL-6, TGF-beta, LIF, TNF-alpha, TNF-beta by reverse northern and dot blot hybrization. The housekeeping gene, gapdh, was used as an internal control. The results show that in bone of rat, the stable expression of col I alpha (1), col I alpha(2) and col III are related to age not ovariectomy, while supplement with E2 can inhibit the expression of col III and col I alpha(2) completely. The expression of col V, IL-1, IL-6 can be inhibited by estrogen and recovered by removal of estrogen by OVX, then addition of E2 decreased it to the normal level. The expression of TGF-beta is also inhibited by estrogen. It increased during one month after overiectomy, and partially decreased in E2 complemented rat. Three months after surgery, the level of increasing and decreasing is less evident as two months ago. It seems that in young SD rat, the expression of TGF-beta is related to both estrogen and age.


Subject(s)
Collagen/biosynthesis , Cytokines/biosynthesis , Estradiol/pharmacology , Femur/metabolism , Age Factors , Animals , Female , Gene Expression , Ovariectomy , RNA, Messenger/biosynthesis , Rats , Rats, Sprague-Dawley
13.
Se Pu ; 17(6): 588-9, 1999 Nov.
Article in Chinese | MEDLINE | ID: mdl-12552701

ABSTRACT

The quantitative analysis of the three antibiotics-tetracycline(TC), oxytetracycline(OTC) and chlortetracyclinum(CTC) was carried out with a self-packed Hypersil C18 150 mm x 0.5 mm i.d. column. As little as 0.5 nanogram of antibiotics can be well detected, the capillary high performance liquid chromatographic method is 100 times more sensitive than that with ordinary HPLC method. The coefficients of linear correlation of mass concentration from 0.5 nanogram to 20 nanogram were rOTC = 0.99695, rTC = 0.99778 and rOTC = 0.98836. It showed that capillary HPLC is a good method used for sensitive analysis of antibiotics in honey.


Subject(s)
Anti-Bacterial Agents/analysis , Chromatography, High Pressure Liquid/methods , Drug Residues/analysis , Honey/analysis , Chlortetracycline/analysis , Oxytetracycline/analysis , Tetracycline/analysis
14.
Magn Reson Med ; 29(2): 188-95, 1993 Feb.
Article in English | MEDLINE | ID: mdl-8429782

ABSTRACT

A new perfluorocarbon, PTBD (perfluoro-2,2,2',2'-tetramethyl-4,4'-bis(1,3-dioxolane)), is described for use in 19F MR imaging and spectroscopy. Two-thirds of the molecular fluorine in PTBD resonates at a single frequency and can be imaged without the use of frequency-selective spin-echo (SE) MRI pulse sequences to suppress chemical shift artifacts. The absence of strong homonuclear spin-spin coupling to the imagable -CF3 groups in PTBD minimizes signal attenuation in 19F SE MRI due to J-modulation effects. For equimolar concentrations of perfluorocarbon, PTBD gives an approximately 17% increase in sensitivity, relative to literature results for perfluorinated amines, at short values of TE (approximately 10 ms) in 19F SE MRI. These attributes allow 19F MRI of PTBD to be performed on standard clinical imaging instrumentation (without special hardware and/or software modification) and an in vivo example in a mouse is shown. This investigation involved characterizing the MR T1 and T2 relaxation times of PTBD as well as the MR spin-lattice relaxation rate, R1 (1/T1), of PTBD as a function of dissolved oxygen concentration. The T1 and T2 relaxation times and R1 relaxation rates of perfluorooctyl bromide (PFOB) were also obtained, under similar experimental conditions, to compare and contrast PTBD with a representative perfluorocarbon that has been widely employed for 19F MRI/MRS applications.


Subject(s)
Dioxolanes , Fluorocarbons , Magnetic Resonance Imaging/methods , Magnetic Resonance Spectroscopy , Animals , Fluorine , Magnetic Resonance Spectroscopy/methods , Mice , Mice, Inbred C3H , Models, Structural , Tissue Distribution
15.
Zhonghua Zhong Liu Za Zhi ; 9(5): 325-7, 19, 1987 Sep.
Article in Chinese | MEDLINE | ID: mdl-2968233

ABSTRACT

In this paper, light and electron micrographs of Ehrlich ascites tumor cells radiated by gamma-ray and influenced by hematoporphyrin derivative (HPD) were analysed by morphometric method. It was found that in these cells, the domain of microfilaments treated by HPD expanded extensively, which enhanced the damage of cells induced by gamma-ray. Twenty five minutes after radiation, the cellular fragments increased, resulting in a decrease in the mean diameter of cells and an increase of nuclear volume density and nucleocytoplasmic ratio. In addition, ribosomes on the rough endoplasmic reticulum surfaces fell off increasingly and the quantity of smooth endoplasmic reticula increased.


Subject(s)
Hematoporphyrins/pharmacology , Radiation-Sensitizing Agents/pharmacology , Tumor Cells, Cultured/drug effects , Animals , Carcinoma, Ehrlich Tumor , Cell Nucleus/radiation effects , Gamma Rays , Hematoporphyrin Derivative , In Vitro Techniques , Mice , Tumor Cells, Cultured/radiation effects
16.
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