Size-dependent free vibration of nano/microbeams with piezo-layered actuators

Micro & nano letters

article

Mostafa Nazemizadeh¹  F. Bakhtiari-Nejad¹ 

[1] Department of Mechanical Engineering, Amirkabir University of Technology

关键词: microactuators;    nanoactuators;    set theory;    piezoelectric actuators;    size-dependent free vibration;    nanomicrobeam;    size-dependent dynamic modelling;    piezolayered beam actuator;    nonlocal continuum theory;    motion equation;    boundary condition;    Hamilton principle;    nonlocal size scale parameter;   

DOI  :  10.1049/mnl.2014.0317

学科分类：计算机科学（综合）

来源: Wiley

【 摘 要 】

Background and objective: Postoperative pain requires a well-planned analgesia regimen to ensure adequate patient comfort, satisfaction, early mobilization and also to decrease the hospital stay after anesthesia. We conducted this study to compare the transversus abdominis plane block with direct infiltration of bupivacaine into surgical incision in cesarean section to prolong the mean duration of postoperative analgesia. Methodology: This Randomized control trial was conducted in department of anesthesia, Nishtar Hospital, Multan from July 2016 to December 2016. A total of sixty patients were included in the study and randomly divided into two equal groups of 30 each; Group-T and Group-I. Group-T received TAP block with 0.3 ml/kg of 0.25% bupivacaine on each side under double pop technique, and Group-I received 0.6 ml/kg of 0.25% bupivacaine infiltration in surgical incision. Postoperatively all the patients were monitored in PACU. VAS was noted at 1/2, 1, 2, 4 and 6 h intervals. Inj tramadol 1.5 ml/kg was given as rescue analgesia when VAS score ≥4. Time to requirement of first rescue analgesia was noted. Sample size was calculated with 80% power of test, 95 % confidence interval taking mean and standard deviation of rescue analgesia in Group-T 148 ± 46.7 and in Group-I 85.38 ± 38.07. Data were analyzed with computer software SPSS version 23. Mean ± SD was calculated for quantitative variables and frequency (percentage) was calculated for qualitative variables. Student t-test and chi square test were applied. P value 0.05 was considered as significant.

【 授权许可】

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