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1.
Angew Chem Int Ed Engl ; 62(39): e202309614, 2023 Sep 25.
Article in English | MEDLINE | ID: mdl-37552235

ABSTRACT

Conducting polymers with high theoretical capacitance and deformability are among the optimal candidates for compressible supercapacitor electrode materials. However, achieving both mechanical and electrochemical stabilities in a single electrode remains a great challenge. To address this issue, the "Polymer Chainmail" is proposed with reversible deformation capability and enhances stability because of the steric hindrance and charge compensation effect of doped anions. As a proof of concept, four common anions are selected as dopants for Poly(3,4-ethylenedioxythiophene) (PEDOT), and their effects on the adsorption and diffusion of H+ on PEDOT are verified using density functional theory calculations. Owing to the film formation effect, the PF 6 - ${{\rm{PF}}_6^- }$ doped PEDOT/nitrogen-doped carbon foam exhibits good mechanical properties. Furthermore, the composite demonstrates excellent rate performance and stability due to suitable anion doping. This finding provides new insights into the preparation of electrochemically stable conductive polymer-based compressible electrode materials.

2.
Shanghai Kou Qiang Yi Xue ; 27(6): 661-663, 2018 Dec.
Article in Chinese | MEDLINE | ID: mdl-30899953

ABSTRACT

PURPOSE: To standardize the teaching process of interns in dental technology so as to make the learning progress and process goals more clearly and improve the teaching quality. METHODS: Thirty-two junior interns were selected from medical colleges and universities from 2014 to 2017, based on same learning ability, learning attitude, learning achievement and hands-on ability ,they were randomly divided into 2 groups. The experimental group adopted the goal teaching method, using relevant teaching materials, applying theory to practice closely, and trying to standardize practice. The control group entered the production lines directly without teaching materials, the students were all owed only to see, think and manipulate. The data were analyzed with SPSS 18.0 software package. RESULTS: The exam scores of the students in the experimental group were significantly higher than that of the students in the control group. Moreover, the satisfaction with the teaching methods of the experimental group was significantly higher than that of the control group (P<0.05). CONCLUSIONS: The target teaching method is effective in teaching dental technology. Students clearly understand the study progress, process goals and their operational performance is significantly improved.


Subject(s)
Education, Dental , Learning , Technology, Dental , Achievement , Humans , Students , Teaching , Technology, Dental/education , Universities
3.
Chin Med J (Engl) ; 130(13): 1570-1577, 2017 Jul 05.
Article in English | MEDLINE | ID: mdl-28639573

ABSTRACT

BACKGROUND: Chronic intermittent hypoxia is the most remarkable feature of obstructive sleep apnea/hypopnea syndrome and it can induce the change of hypoxia-inducible factor-1α (HIF-1α) expression and contractile properties in the genioglossus. To clarify the role of HIF-1α in contractile properties of the genioglossus, this study generated and compared high-throughput RNA-sequencing data from genioglossus between HIF-1α conditional knockout (KO) mice and littermate wild-type (WT) mice. METHODS: KO mice were generated with cre-loxP strategy. Gene expression profile analysis was performed using gene enrichment analysis. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses of differently expressed messenger RNAs were performed to identify the related pathways and biological functions. Six differentially expressed genes (DEGs) were validated by qualitative reverse transcription polymerase chain reaction. RESULTS: A total of 142 (77 upregulated and 65 downregulated) transcripts were found to exhibit statistically significant difference between the HIF-1α-KO and WT mice. GO and KEGG analyses indicated that DEGs included genes involved in "skeletal muscle cell differentiation," "muscle organ development," "glucose metabolic process," "glycogen biosynthetic and metabolic process," etc. CONCLUSION: This study might provide evidence that HIF-1α affects the expression of multiple genes involved in the myogenesis, muscle development, and carbohydrate metabolism through transcriptome analysis in conditional HIF-1α-KO mice.


Subject(s)
Carbohydrate Metabolism/physiology , Gene Expression Profiling/methods , Hypoxia-Inducible Factor 1, alpha Subunit/genetics , Muscle Development/physiology , Animals , Carbohydrate Metabolism/genetics , Hypoxia-Inducible Factor 1, alpha Subunit/deficiency , Mice , Mice, Inbred C57BL , Mice, Knockout , Muscle Development/genetics , Reverse Transcriptase Polymerase Chain Reaction
4.
Zhonghua Nan Ke Xue ; 21(12): 1093-7, 2015 Dec.
Article in Chinese | MEDLINE | ID: mdl-26817301

ABSTRACT

OBJECTIVE: To search for the optimal strategies for sperm collection from the patient with temporary penile erectile dysfunction (ED) on the day of oocyte pick-up ( OPU) in in vitro fertilization embryo transfer (IVF-ET). METHODS: We retrospectively analyzed 93 cases of temporary ED on the OPU day of IVF-ET from January 2011 to May 2014, with fresh semen for 45 cases (group A), cryopreserved sperm before oocyte retrieval for 30 cases (group B), and frozen oocytes for 18 cases (group C). Group A was again subdivided into A1 (n = 18) and A2 n = 27) , the former intervened with oral sildenafil while the latter left untreated. We compared the rates of fertilization, high-quality embryo, and pregnancy among different groups. RESULTS: No statistically significant differences were found among groups A, B and C in the age of the males and females, duration of infertility, numbers of obtained and mature oocytes, and rates of cleavage, or in the percentages of normal fertilization (80.78% vs 80.43% vs 84.77%), high-quality embryo (53.27% vs 52.97% vs 47.69%) and pregnancy (60.00% vs 56.77% vs 44.44%) (all P > 0.05). The rate of 3PN was markedly lower in group C (0.63%) than in A (9. 61%) and B (4.34%) (P < 0.05). There were no significant differences between groups A1 and A2 in the age of the males and females, duration of infertility, numbers of obtained and mature oocytes, and the rates of fertilization, cleavage, high-quality embryo, and pregnancy (all P > 0.05). CONCLUSION: On the OPU day of IVF-ET, oral sildenafil can help temporary ED men to achieve penile erection and ejaculation without affecting the outcomes of assisted reproduction. Cryopreserved sperm can be used in case of predicted temporary ED and frozen oocytes can also be employed if sperm retrieval fails. However, to avoid puncture injury to the epididymis or testis, fresh semen should be the first choice.


Subject(s)
Erectile Dysfunction/physiopathology , Fertilization in Vitro , Sperm Retrieval , Cryopreservation , Embryo Transfer , Erectile Dysfunction/drug therapy , Female , Fertilization , Humans , Male , Oocyte Retrieval , Oocytes , Penis , Pregnancy , Retrospective Studies , Sildenafil Citrate/therapeutic use , Spermatozoa
5.
Nano Lett ; 13(2): 643-50, 2013 Feb 13.
Article in English | MEDLINE | ID: mdl-23323808

ABSTRACT

We report a novel phase separation phenomenon observed in the growth of ternary In(x)Ga(1-x)As nanowires by metalorganic chemical vapor deposition. A spontaneous formation of core-shell nanowires is investigated by cross-sectional transmission electron microscopy, revealing the compositional complexity within the ternary nanowires. It has been found that for In(x)Ga(1-x)As nanowires high precursor flow rates generate ternary In(x)Ga(1-x)As cores with In-rich shells, while low precursor flow rates produce binary GaAs cores with ternary In(x)Ga(1-x)As shells. First-principle calculations combined with thermodynamic considerations suggest that this phenomenon is due to competitive alloying of different group-III elements with Au catalysts, and variations in elemental concentrations of group-III materials in the catalyst under different precursor flow rates. This study shows that precursor flow rates are critical factors for manipulating Au catalysts to produce nanowires of desired composition.

6.
J Am Chem Soc ; 134(46): 18920-3, 2012 Nov 21.
Article in English | MEDLINE | ID: mdl-23126545

ABSTRACT

Bi(1.85)Mn(0.15)Te(3) hexagonal nanoplates with a width of ~200 nm and a thickness of ~20 nm were synthesized using a solvothermal method. According to the structural characterization and compositional analysis, the Mn(2+) and Mn(3+) ions were found to substitute Bi(3+) ions in the lattice. High-level Mn doping induces significant lattice distortion and decreases the crystal lattice by 1.07% in the a axis and 3.18% in the c axis. A high ferromagnetic state with a Curie temperature of ~45 K is observed in these nanoplates due to Mn(2+) and Mn(3+) ion doping, which is a significant progress in the field of electronics and spintronics.


Subject(s)
Bismuth/chemistry , Hot Temperature , Manganese/chemistry , Nanostructures , Tellurium/chemistry , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , X-Ray Diffraction
7.
Nanoscale Res Lett ; 7(1): 589, 2012 Oct 24.
Article in English | MEDLINE | ID: mdl-23095345

ABSTRACT

In this letter, we quantitatively investigated epitaxial GaAs nanowires catalyzed by thin Au films of different thicknesses on GaAs (111)B substrates in a metal-organic chemical vapor deposition reactor. Prior to nanowire growth, the de-wetting of Au thin films to form Au nanoparticles on GaAs (111)B in AsH3 ambient at different temperatures is investigated. It is found that with increasing film thickness, the size of the Au nanoparticles increases while the density of the nanoparticles reduces. Furthermore, higher annealing temperature produces larger Au nanoparticles for a fixed film thickness. As expected, the diameters and densities of the as-grown GaAs nanowires catalyzed by these thin Au films reflect these trends.

8.
ACS Nano ; 6(7): 6005-13, 2012 Jul 24.
Article in English | MEDLINE | ID: mdl-22724925

ABSTRACT

The doping-dependent photoconductive properties of individual GaAs nanowires have been studied by conductive atomic force microscopy. Linear responsivity against the bias voltage is observed for moderate n-doped GaAs wires with a Schottky contact under illumination, while that of the undoped ones exhibits a saturated response. The carrier lifetime of a single nanowire can be obtained by simulating the characteristic photoelectric behavior. Consistent with the photoluminescence results, the significant drop of minority hole lifetime, from several hundred to subpicoseconds induced by n-type doping, leads to the distinct photoconductive features. Moreover, by comparing with the photoelectric behavior of AlGaAs shelled nanowires, the equivalent recombination rate of carriers at the surface is assessed to be >1 × 10(12) s(-1) for 2 × 10(17)cm(-3) n-doped bare nanowires, nearly 30 times higher than that of the doping-related bulk effects. This work suggests that intentional doping in nanowires could change the charge status of the surface states and impose significant impact on the electrical and photoelectrical performances of semiconductor nanostructures.

10.
Molecules ; 15(4): 2096-102, 2010 Mar 24.
Article in English | MEDLINE | ID: mdl-20428029

ABSTRACT

Four triterpenes 1-4, including a new naturally occurring oleanane-type triterpene 1, were isolated by a multi-step chromatography procedure from the leaves and twigs of Stachyurus himalaicus var. himalaicus Hook. f. et Thoms.ex Benth. The structures of the compounds were elucidated by spectroscopic methods, including HRESIMS, 1H- NMR, 13C-NMR, DEPT, HMQC, HMBC and NOESY spectra. All the isolated compounds were evaluated for their in vitro cytotoxic activities against human Hela cell line.


Subject(s)
Antineoplastic Agents/isolation & purification , Cytotoxins/isolation & purification , Ferns/chemistry , Triterpenes/isolation & purification , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Cytotoxins/chemistry , Cytotoxins/pharmacology , HeLa Cells , Humans , Triterpenes/chemistry , Triterpenes/pharmacology
11.
Molecules ; 14(2): 771-6, 2009 Feb 13.
Article in English | MEDLINE | ID: mdl-19223825

ABSTRACT

A new O-terpenoidal coumarin 1, named hekumarone, was isolated from the leaves and twigs of Clausena anisum-olens Merr.(Rutaceae) collected in Hekou County in Yunnan Province, P.R. China. Structure elucidation and unambiguous NMR assignments for the title compound was carried out on the basis of 1D and 2D NMR experiments.


Subject(s)
Clausena/chemistry , Coumarins/chemistry , Plant Extracts/chemistry , Terpenes/chemistry , Drugs, Chinese Herbal/chemistry , Medicine, Chinese Traditional , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular
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