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1.
Materials (Basel) ; 17(10)2024 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-38793520

RESUMO

Magnesium matrix composites are essential lightweight metal matrix composites, following aluminum matrix composites, with outstanding application prospects in automotive, aerospace lightweight and biomedical materials because of their high specific strength, low density and specific stiffness, good casting performance and rich resources. However, the inherent low plasticity and poor fatigue resistance of magnesium hamper its further application to a certain extent. Many researchers have tried many strengthening methods to improve the properties of magnesium alloys, while the relationship between wear resistance and plasticity still needs to be further improved. The nanoparticles added exhibit a good strengthening effect, especially the ceramic nanoparticles. Nanoparticle-reinforced magnesium matrix composites not only exhibit a high impact toughness, but also maintain the high strength and wear resistance of ceramic materials, effectively balancing the restriction between the strength and toughness. Therefore, this work aims to provide a review of the state of the art of research on the matrix, reinforcement, design, properties and potential applications of nano-reinforced phase-reinforced magnesium matrix composites (especially ceramic nanoparticle-reinforced ones). The conventional and potential matrices for the fabrication of magnesium matrix composites are introduced. The classification and influence of ceramic reinforcements are assessed, and the factors influencing interface bonding strength between reinforcements and matrix, regulation and design, performance and application are analyzed. Finally, the scope of future research in this field is discussed.

2.
Appl Opt ; 60(25): 7775-7783, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34613250

RESUMO

A design method and corresponding fabrication procedures are proposed for a dual frusto-conical reflector of a downlight luminaire. The profile of the dual frusto-conical reflector consists of two flat-slant reflective surfaces with slightly different slopes. The optimum dual frusto-conical reflector can be obtained with the proposed design method. The finished product of the dual frusto-conical reflector is fabricated by a 3D printer and followed by surface polishing and reflection paint spraying. The measurement results show that luminaires exhibited 70% optimum illuminance confined within an illumination area of 1.8m2, and the optimum illumination intensity is at 252 lux. The optimum efficiency of the proposed luminaire can reach 158 lm/W for normal-white light-emitting diode (LED) and 119 lm/W for warm-white LED, respectively.

3.
China Pharmacy ; (12): 813-815, 2018.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-704682

RESUMO

OBJECTIVE:To observe therapeutic efficacy and safety of metoprolol combined with Shensong yangxin capsule in the treatment of ventricular premature beat. METHODS:A total of 104 patients with ventricular premature beat during Jan. 2016-Jan. 2017 were analyzed retrospectively,and they were divided into control group(52 cases)and observation group(52 cases)according to medication plan. Control group was given Metoprolol tartrate tablet 25 mg orally,3 times a day. Observation group was given Shensong yangxin capsule 1.2 g orally,3 times a day,on the basis of control group. Both groups were treated for consecutive 28 d. Clinical efficacies of 2 groups were observed. The electrocardiogram P-R interval and Q-T interval,24 h premature beat times,heart rate,the occurrence of palpitation before and after treatment and ADR were observed. RESULTS:Total response rate of observation group(92.30%)was significantly higher than that of control group(76.92%),with statistical significance(P<0.05).Before treatment, there was no statistical significance in electrocardiogram P-R interval and Q-T interval,24 h premature beat times,heart rate or palpitation times between 2 groups(P>0.05). After treatment,electrocardiogram P-R interval and Q-T interval of 2 groups were significantly higher than before treatment,and the observation group was significantly higher than the control group. 24 h premature beat times,palpitation times of 2 groups and heart rate of control group were significantly lower than before treatment;and 24 h premature beat times,palpitation times of the observation group was significantly lower than the control group,with statistical significance(P<0.05);there was no statistical significance in heart rate of observation group before and after treatment(P>0.05). There was no statistical significance in the total incidence of ADR between 2 groups(P>0.05). CONCLUSIONS:For ventricular premature beat,metoprolol combined with Shensong yangxin capsule show significant therapeutic efficacy,can reduce the times of premature beat and improve patients'electrocardiogram without increasing the occurrence of ADR.

4.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-669654

RESUMO

Objective To evaluate the application effects of mind map in community health education of rheumatoid arthritis patients. Methods 65 rheumatoid arthritis patients from Shunqing district of Nanchong City, Sichuan Province were randomly divided into an observation group (n=33) and a control group(n=32). Both groups received six-month health education. Health educators utilized mind map for the observation group and traditional health education for the control group. Before and after implementation, the two groups' mastery of disease knowledge was compared. During the period of 1, 3, 6 months, two groups received compliance evaluation respectively. During the study period, a questionnaire was given to the observation group to collect their attitude towards the mind map health education and their evaluation about it. Measurement data was represented by x ± s, using group t-test design information and single-sample t-test. χ2test was used in the count data for compar-ison between groups with test levelα=0.05. Results The scores of disease knowledge were as follows. Before implementation there was no statistically significant difference between two groups (P=0.921);After implementation, the score of observation group was(19.97±3.03), while the score of control group was(17.59±3.11), the difference was statistically significant(t=3.122,P=0.003). The difference of 1,3,6-month compliance scores was statistically significant(t=2.173,P=0.034;t=2.371,P=0.021;t=2.615,P=0.011) with the observation group's scores(18.24±3.44),(18.94±3.25),(19.64±3.06) respectively,and the control group's scores(16.47±3.13),(16.97±3.45),(17.44±3.70). Observation group's attitude questionnaire scores of each project are > 3, and there was significant difference be-tween two groups (P=0.000). Conclusion Mind mapping method can be used in community health education for rheumatoid arthritis patients to help patients master the knowledge of the disease and improve the compliance. Its effect is better than traditional methods.

5.
J Virol Methods ; 191(2): 155-61, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22584269

RESUMO

A loop-mediated isothermal amplification (LAMP) assay was developed for detection of bovine parvovirus (BPV) DNA. Four primers were designed to recognize six distinct regions on the target DNA based on a highly conserved sequence in the VP2 region of the BPV genome. The optimized LAMP reaction conditions were 8 mM Mg²âº, 1.2 mM betaine, and an incubation at 63°C for 45 min. After amplification the products were detected either by observing a ladder pattern following gel electrophoresis, observation of turbidity, or a color change with the addition of SYBR Green I to the reaction tube. The detection limit of the LAMP assay was 9 copies of BPV-DNA and was 100 times more sensitive than conventional PCR. A ladder pattern of bands after gel electrophoresis was observed for only BPV isolates and showed that the BPV LAMP assay was highly specific without any cross-reactivity with other related viruses. The LAMP assay was evaluated further using 59 field samples and the results were comparable to conventional PCR. The LAMP assay is a simple, rapid and economic detection method; it can provide a useful technique suitable for detection of BPV infection in both field conditions and laboratory settings.


Assuntos
Bocavirus/isolamento & purificação , Doenças dos Bovinos/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Infecções por Parvoviridae/veterinária , Medicina Veterinária/métodos , Animais , Bocavirus/genética , Bovinos , Doenças dos Bovinos/virologia , Primers do DNA/genética , DNA Viral/genética , Infecções por Parvoviridae/virologia , Sensibilidade e Especificidade
6.
Artigo em Chinês | MEDLINE | ID: mdl-22338229

RESUMO

OBJECTIVE: To discuss the epidemiological and clinical characteristics of the hospitalized children with hand foot and mouth disease (HFMD) in Yantai area. METHODS: Epidemiological and clinical data of HFMD children from 2009 to 2010 were summarized and analyzed retrospectively. RESULTS: Most of the infected (94.6%) were under 5 years old and the ratio between male and female was 1.5: 1. Oral mucosal pox or ulcer as well as hand and foot rashes were observed in all 931 patients. Fever and neurological disorders occurred in 840 (90.2%) and 121 (13.0%) patients respectively. The incidence was positively correlated with air temperature (r = 0.887, P < 0.001), with a peak in April to September (88.9%). The ratio of children from countryside, total duration of fever, serum concentration of c-reacting protein (CRP) and fasting blood glucose (FBG) were significantly higher in severe cases than in those mild ones. Multivariate analysis showed longer mean duration of fever( Odds ratio [OR], 1.491; 95% confidence interval [ CI] 1.170-1.901; P = 0.001) and hyperglycemia (OR, 1.124; 95% CI 1.016-1.245; P = 0.024) were independent risk factors of severity. CONCLUSION: Children younger than 5 years old are susceptible to HFMD and most cases occur in April to September. The monthly incidence is positively correlated with temperature of that month. Longer duration of fever and hyperglycemia are independent risk factors for severity. Most cases could have a favorable prognosis after timely diagnosis and proper intervention.


Assuntos
Doença de Mão, Pé e Boca/epidemiologia , Adolescente , Criança , Pré-Escolar , China/epidemiologia , Estudos Epidemiológicos , Feminino , Humanos , Incidência , Lactente , Masculino , Estudos Retrospectivos , Estações do Ano , Temperatura
7.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-246235

RESUMO

<p><b>OBJECTIVE</b>To discuss the epidemiological and clinical characteristics of the hospitalized children with hand foot and mouth disease (HFMD) in Yantai area.</p><p><b>METHODS</b>Epidemiological and clinical data of HFMD children from 2009 to 2010 were summarized and analyzed retrospectively.</p><p><b>RESULTS</b>Most of the infected (94.6%) were under 5 years old and the ratio between male and female was 1.5: 1. Oral mucosal pox or ulcer as well as hand and foot rashes were observed in all 931 patients. Fever and neurological disorders occurred in 840 (90.2%) and 121 (13.0%) patients respectively. The incidence was positively correlated with air temperature (r = 0.887, P < 0.001), with a peak in April to September (88.9%). The ratio of children from countryside, total duration of fever, serum concentration of c-reacting protein (CRP) and fasting blood glucose (FBG) were significantly higher in severe cases than in those mild ones. Multivariate analysis showed longer mean duration of fever( Odds ratio [OR], 1.491; 95% confidence interval [ CI] 1.170-1.901; P = 0.001) and hyperglycemia (OR, 1.124; 95% CI 1.016-1.245; P = 0.024) were independent risk factors of severity.</p><p><b>CONCLUSION</b>Children younger than 5 years old are susceptible to HFMD and most cases occur in April to September. The monthly incidence is positively correlated with temperature of that month. Longer duration of fever and hyperglycemia are independent risk factors for severity. Most cases could have a favorable prognosis after timely diagnosis and proper intervention.</p>


Assuntos
Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , China , Epidemiologia , Estudos Epidemiológicos , Doença de Mão, Pé e Boca , Epidemiologia , Incidência , Estudos Retrospectivos , Estações do Ano , Temperatura
8.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-397663

RESUMO

Objective To clarify great benefit to prevention of wound infection as well as reduction of economic expenditures by a new method of connecting latex gloves and cigarettes in peritoneal drainage. Methods We randomly selected 121 cases of patients with peritoneal pyogenic infection, divided them into the latex gloves group (64 eases)and the common dressing group (57 cases). The incision infection rate and eco-nomic cost in two groups were comparately studied. Results The latex gloves group's incision infection rate was 10.94% (7 / 64), the common dressing was 31.58% (18/57). Each patient of the latex gloves group spent less cost about 15.70 yuan,changed dressing 5.3 times less than the common dressing group. Conclusions Connecting latex gloves and cigarettes in peritoneal drainage is a new method of reducing economic expandi-tures and the chances of incision infection. Clinical application of this method should be fully prospected.

9.
J Colloid Interface Sci ; 313(1): 374-7, 2007 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-17466322

RESUMO

The surface tension of ionic liquid (IL) C(5)MIBF(4) (1-methyl-3-pentylimidazolium tetrafluoroborate) with various amount of water was measured by the forced bubble method at 278.15 to 338.15+/-0.05 K. In terms of standard addition method, the surface tension of pure IL C(5)MIBF(4) was obtained. The properties of surface for pure C(5)MIBF(4) were discussed in terms of the principle of independent surface action and Glasser's theory of lattice energy. Using the surface tension data, the interstice model was examined.

10.
Artigo em Inglês | MEDLINE | ID: mdl-16246612

RESUMO

A novel fish-specific apolipoprotein (apo-14 kDa) has been recently cloned from eel and pufferfish. However, its expression pattern has not been elucidated. In this study, EcApo-14 has been screened from hypothalamic cDNA library of male orange-spotted grouper, which shows 62.9%, 51%, 46.9%, 43.2%, and 31.9% identities to Apo-14 of European flounder, pufferfish, Japanese eel, gibel carp, and grass carp, respectively. RT-PCR analysis reveals that this gene is first transcribed in neurula embryos and maintains a relatively stable expression level during the following embryogenesis. EcApo-14 transcripts are at a very high level during embryonic and early larval development in the yolk syncytial layer (YSL), and decrease in YSL and form intense staining in liver at 3 days after hatching. In adult tissues, EcApo-14 is predominantly expressed in liver and brain. The data suggested that EcApo-14 might play an important role in liver and brain morphogenesis and growth.


Assuntos
Apolipoproteínas/genética , Regulação da Expressão Gênica no Desenvolvimento , Sequência de Aminoácidos , Animais , Apolipoproteínas/metabolismo , Sequência de Bases , Encéfalo/citologia , Encéfalo/metabolismo , Clonagem Molecular , DNA Complementar/química , DNA Complementar/genética , Fígado/citologia , Fígado/metabolismo , Masculino , Dados de Sequência Molecular , Especificidade de Órgãos/genética , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Tetraodontiformes/genética
11.
FASEB J ; 18(10): 1108-10, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15132985

RESUMO

Nitric oxide (NO) is thought to play an important role as a signaling molecule in embryonic and adult cardiomyocytes; however, its involvement in muscarinic signaling is still unclear. The aim of the present work was to analyze the muscarinic modulation of the L-type Ca2+ current (ICa) in early- and late-stage embryonic ventricular cardiomyocytes. Muscarinic stimulation depressed basal ICa by 30.1 +/- 3.2% (n=27) in early-stage cardiomyocytes. Pharmacological evidence suggested that the muscarinic modulation was mediated through generation of NO, activation of cGMP-dependent phosphodiesterase (PDE) 2, and ensuing lowering of cyclic AMP/protein kinase A (cAMP/PKA) levels. Conversely, in late-stage cardiomyocytes, muscarinic regulation of ICa occurred in a NO-independent manner via inhibition of prestimulated adenylyl cyclase (AC). To unequivocally prove the involvement of NO and to identify the nitric oxide synthase (NOS) isoform(s), we analyzed muscarinic signaling in embryonic ventricular cardiomyocytes of NOS2 (-/-) and NOS3 (-/-) mice. The early-stage NOS3 (-/-) cardiomyocytes lacked muscarinic modulation, whereas it was preserved in NOS2 (-/-) cells. Moreover, at the late embryonic stage, muscarinic modulation of ICa was intact in both strains. Thus, NO is the key regulator of muscarinic signaling in the early embryonic ventricle, whereas at later stages, signaling occurs through a NO-independent pathway.


Assuntos
Canais de Cálcio Tipo L/metabolismo , Cálcio/metabolismo , Coração Fetal/fisiologia , Óxido Nítrico/fisiologia , Transdução de Sinais/fisiologia , Animais , Animais não Endogâmicos , Carbacol/farmacologia , Colinérgicos/farmacologia , Proteína Quinase Tipo II Dependente de AMP Cíclico , Proteínas Quinases Dependentes de AMP Cíclico/farmacologia , Feminino , Guanilato Ciclase/antagonistas & inibidores , Guanilato Ciclase/farmacologia , Ventrículos do Coração/citologia , Ventrículos do Coração/embriologia , Transporte de Íons/efeitos dos fármacos , Camundongos , Camundongos Knockout , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase/fisiologia , Óxido Nítrico Sintase Tipo II , Óxido Nítrico Sintase Tipo III , Toxina Pertussis/farmacologia , Inibidores de Fosfodiesterase/farmacologia , Receptores Muscarínicos/efeitos dos fármacos , Receptores Muscarínicos/fisiologia , Transdução de Sinais/efeitos dos fármacos , ômega-N-Metilarginina/farmacologia
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