This paper uses AVR16 SCM, programming to achieve the software of PWM (pulse width modulation) control of intelligent H bridge chip LMD18200 driver of high speed DC motor, makes special speed tablet, obtains speed signal of high speed for photocoupler PC817, through the A/D conversion and processing circuit, and realizes the LED LCD digital display speed scheme. The driver for the pediatric ventricular assist device has been used at the laboratory trial, has high performance and wide application prospect.
Child ; Heart-Assist Devices ; Humans ; Software

Objective To explore the clinical characteristics of neonatal dengue fever. Methods The clinical data from 4 neonates with dengue fever who were admitted and treated in 2014 were retrospectively analyzed and the related literatures had been reviewed. Results Four cases of neonatal dengue fever were all males. Three cases were mother to child transmission, the age at onset was 1 to 7 days after birth, and their mothers suffered with prenatal fever and were diagnozed of dengue fever during perinatal period. One case was community acquired, the age at onset was day 21 after birth and the neonate was bit by mosquito the day before. All four neonates had fever, two cases had rash, and one case had hemorrhagic spot. None of them had jaundice or cough. All of them had thrombocytopenia ( 30-125 )× 109/L, prolonged activated partial thromboplastin time ( 44 . 0-89 . 8 s), and increased aspartate aminotransferase (AST) ( 46-71 U/L). Three cases had declined ifbrinogen ( 1 . 36-2 . 53 g/L). Two cases had increased CK-MB ( 29-86 U/L). Two cases had increased CRP ( 3 . 00-46 . 05 mg/L). After the treatment of anti-infection and intravenous immunoglobulin, all of them were cured and discharged. The duration of hospital stay was 4-17 days. Conclusion The clinical manifestations of neonatal dengue fever were mainly fever and blood coagulation dysfunction, clinical symptoms are mild and lack of speciifcity, and prognosis are good. Mother to child transmission is one of the ways of dengue virus infection.

This paper uses AVR16 SCM, programming to achieve the software of PWM (pulse width modulation) control of intel igent H bridge chip LMD18200 driver of high speed DC motor, makes special speed tablet, obtains speed signal of high speed for photocoupler PC817, through the A/D conversion and processing circuit, and realizes the LED LCD digital display speed scheme. The driver for the pediatric ventricular assist device has been used at the laboratory trial, has high performance and wide application prospect.

Objective:To investigate the value of using ultrasound excited contrast agents to assess extracorporeal hydrostatic pressure on the basis of ultrasound contrast imaging.Methods:An extracorporeal hydrostatic pressure evaluation system was established. The changes in contrast intensity was first evaluated for the same concentration of microbubble contrast agent at ambient pressures of 20, 25, 30, 35, 40, and 45 cmH 2O. Contrast agents with the same initial intensity were placed at different pressures for 1 s, 3 s, and 5 s, and the percentage change in contrast agent intensity was analyzed to select the optimal excitation time. Finally, the contrast agent at different pressures was stimulated using an acoustic excitation device, and correlation analysis was performed using the Pearson product moment correlation coefficient. Linear regression analysis was used to establish the relationship between different pressures and the percentage change in intensity. Results:When the ambient pressure was varied under 6 gradients of 20, 25, 30, 35, 40, and 45 cmH 2O, the contrast strength decreased with the pressure increased, and there was a negative correlation between contrast strength and the pressure ( r=-0.971, P<0.001). Under different pressures, the contrast agent intensity showed different degrees of natural decrease in 1 s, 3 s, and 5 s. The difference in the percentage change in contrast agent intensity in each pressure gradient was not statistically significant in 1 s ( P>0.05), whereas the differences in the percentage change in contrast agent intensity in 3 s and 5 s were statistically significant in each pressure gradient (all P<0.05). After microbubble contrast agent was stimulated by ultrasound excitation for 1s, the percentage change in contrast agent intensity was significantly correlated with ambient pressure ( r=-0.976, P<0.001). A linear regression model was fitted with the percentage change in contrast agent intensity after 1 s of stimulation as the independent variable and the pressure as the dependent variable, with the model equation: y=60.075-2.559×x1, where x1 is the percentage change in contrast agent ( R2=0.952, P<0.001). Conclusions:The percentage change in contrast intensity after 1 s of ultrasound excitation of microbubble contrast agent is a favorable predictor of hydrostatic pressure at 6 pressure gradients of 20, 25, 30, 35, 40, and 45 cmH 2O, which may provide a new method for noninvasive monitoring of portal vein pressure for clinicans.

Objective The identification of Santali Albi Lignum and its common counterfeits Osyris lanceolata Lignum,Santalum spicatum Lignum was studied to provide experimental basis for the authenticity of this medicinal herb.Methods The identification was carried out using morphological,microscopic,and thin-layer identification methods.The volatile oil of Santali Albi Lignum and its counterfeits were extracted by steam distillation and the volatile oil components were analyzed by gas chromatography-mass spectrometry(GC-MS).The differences of volatile oil components among the three were compared.Results Santali Albi Lignum and its common counterfeits all possessed a sandalwood aroma,but Santali Albi Lignum has abundant oiliness and strong aroma.Osyris lanceolata Lignum aroma exhibits slightly strong odor and slightly camphor flavor,and the smell of Santalum spicatum Lignum is sweet and fragrant.Santali Albi Lignum is greyish-yellow to yellowish-brown in color,while Osyris lanceolata Lignum is generally reddish brown in color,Santalum spicatum Lignum is light yellow to light yellowish-brown,but its surface shows reddish-brown when exposed to air for a long time.In the transection section,the ray width of Santali Albi Lignum is more than 1-2 rows of cells,with occasional 3 rows of cells.The ray width of Osyris lanceolata Lignum is 1-3 rows of cells,while the ray width of Santalum spicatum Lignum is 1-2 rows of cells,mostly uniseriate.In the tangential section,the wood ray of Santali Albi Lignum has a height of 5-15 cells,the wood ray of Osyris lanceolata Lignum has a height of 4-10 cells,while the wood ray of Santalum spicatum Lignum has a height of 4-16 cells.In the radial section,fewer calcium oxalate crystal was found in Santali Albi Lignum,more calcium oxalate crystal was appeared in Osyris lanceolata Lignum,more and larger calcium oxalate crystal was identified in Santalum spicatum Lignum.Genuine and fake sandalwood can be distinguished using sandalwood oil as the thin-layer chromatographic reference.And the volatile oil content of fake Osyris lanceolata Lignum and Santalum spicatum Lignum is lower than that of Santali Albi Lignum.The main components of Santali Albi Lignum are α-santalol and β-santalol.The low content of santalol has been found in Osyris lanceolata Lignum,while α-santalol is extremely low in Santalum spicatum Lignum oil and β-santalol has not been found.Conclusion There are small differences among Santali Albi Lignum and its adulterants in characteristics,microscopical characteristics.But the differences have been found in three-way cross section,thin layer chromatography,volatile oil content and composition characteristics,which can be used for identification of Santali Albi Lignum and its counterfeits.