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1.
Comput Methods Biomech Biomed Engin ; 13(1): 11-8, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19488911

RESUMO

Pneumatic muscle actuators (PMAs) offer significant advantages over more traditional actuators, which make them prime candidates in rehabilitation devices. A dynamic test station (DTS) is modified to demonstrate the use of a PMA for this application. The DTS includes two dynamic systems: a PMA and a DC servomotor. An overall transfer function was developed utilising characterisation data for the PMA and DC servomotor. A Tustin (bilinear) transform was performed on the overall transfer function to obtain a discrete time system. Model parameters were optimised and used to generate input voltage profiles that achieve isokinetic (constant velocity) task specifications. Percent root mean square error values (PRMSE) between the actual and ideal profiles were used to evaluate the accuracy of this method in achieving isokinetic displacement. For PMA pressures (in kPa) of 150, 350 and 550 PRMSE were 7.80, 5.40 and 2.76, respectively.


Assuntos
Materiais Biomiméticos , Dispositivos de Compressão Pneumática Intermitente , Músculo Esquelético/fisiologia , Fenômenos Biomecânicos , Engenharia Biomédica , Humanos , Dispositivos de Compressão Pneumática Intermitente/estatística & dados numéricos , Modelos Biológicos , Modelos Teóricos , Contração Muscular , Pressão , Torque
2.
Aviat Space Environ Med ; 62(4): 356-62, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2031642

RESUMO

This paper describes the design and capabilities of a noninvasive system to record the superficial temporal artery (STA) pulse pressure during diving scenarios in pilots. The Piezoelectric Pulse Pressure Monitoring System (P3) records the "best" waveform from an array of piezoelectric benders in contact with the skin above the STA during +1 Gz acceleration and then continuously monitors it during +Gz acceleration for determination of G-LOC conditions. Results indicate that P3 may be used in a cockpit environment and may be the controller in an aircraft autorecovery system.


Assuntos
Medicina Aeroespacial , Determinação da Pressão Arterial/métodos , Pulso Arterial , Artérias Temporais , Aceleração , Determinação da Pressão Arterial/instrumentação , Determinação da Pressão Arterial/normas , Estudos de Viabilidade , Gravitação , Humanos
3.
Am J Med Genet ; 34(2): 168-72, 1989 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2816993

RESUMO

Familial Mediterranean fever (FMF) is a recurrent episodic inflammatory disorder of unknown pathogenesis that occurs with high frequency in non-Ashkenazi Jews and Armenians. However, there are some differences in the clinical manifestations of FMF in these ethnic groups. FMF has been reported to be an autosomal recessive disease in non-Ashkenazi Jews, with a male/female ratio of 1.7, indicating reduced penetrance in females. However, the inheritance is less clear for Armenians. To resolve this problem, we studied prospectively families of 64 Armenian index cases randomly ascertained at the UCLA FMF clinic. Fifty-three families containing 176 sibs in addition to the probands were analyzed by genetic segregation analysis (exclusions included: six single-child families, four families in which one of the parents was also affected, and a family with incomplete information). Upper and lower bounds of the segregation ratio were estimated, and ranged from .10 +/- .03 to .18 +/- .05 when only definitely affected sibs were classified as affected; .17 +/- .04 to .27 +/- .05 when considering "possibly affected" sibs as affected; and .19 +/- .04 to .30 +/- .05 when incomplete penetrance in females was corrected. A value of .25 is the expected segregation ratio for autosomal recessive inheritance, and our data are consistent with this mode of inheritance. We can reject autosomal dominant inheritance, where the expected segregation ratio is .5. Using extended pedigree data, we calculated an FMF gene frequency of 0.073 and a carrier rate of 1/7, which is about four times the frequency in non-Ashkenazi Jews.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Febre Familiar do Mediterrâneo/genética , Frequência do Gene , Genes Recessivos , Adolescente , Adulto , Armênia , Criança , Pré-Escolar , Troca Genética , Feminino , Testes Genéticos , Humanos , Lactente , Masculino
4.
J Virol ; 61(6): 1814-20, 1987 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3033313

RESUMO

An in vitro replication system for mouse hepatitis virus (MHV) strain A59 was developed using lysolecithin to produce cell extracts. In extracts of MHV-infected cells, radiolabeled UMP was incorporated at a linear rate for up to 1 h into RNA, which hybridized to MHV-specific cDNA probes and migrated in denaturing formaldehyde-agarose gels to the same position as MHV genomic RNA. The incorporation of [32P]UMP into genome-sized RNA in vitro correlated with the observed increase of [3H]uridine incorporation in MHV-infected cells labeled in vivo. Incorporation of [32P]UMP into genome-sized RNA was inhibited when extracts were incubated with puromycin. The addition to the assay of antiserum to the MHV-A59 nucleocapsid protein N inhibited synthesis of genome-sized RNA by 90% compared with the addition of preimmune serum. In contrast, antiserum to the E1 or E2 glycoproteins did not significantly inhibit RNA replication. In vitro-synthesized RNA banded in cesium chloride gradients as a ribonucleoprotein complex with the characteristic density of MHV nucleocapsids isolated from virions. These experiments suggest that ongoing protein synthesis is necessary for replication of MHV genomic RNA and indicate that the N protein plays an important role in MHV replication.


Assuntos
Vírus da Hepatite Murina/fisiologia , RNA Viral/biossíntese , Replicação Viral , Animais , Anticorpos Antivirais/imunologia , Capsídeo/imunologia , Capsídeo/fisiologia , Linhagem Celular , Permeabilidade da Membrana Celular/efeitos dos fármacos , RNA Polimerases Dirigidas por DNA/antagonistas & inibidores , RNA Polimerases Dirigidas por DNA/metabolismo , Fibroblastos/metabolismo , Cinética , Lisofosfatidilcolinas/farmacologia , Camundongos , Puromicina/farmacologia , Proteínas do Core Viral/imunologia , Proteínas do Core Viral/fisiologia , Proteínas Virais/antagonistas & inibidores , Proteínas Virais/metabolismo
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