Search

Herein, we design a simple and portable biosensing platform for the quantitative detection of cocaine based on target-triggered glucose release from a TiO2 nanotube array (TiNTA) with a glucometer readout. Initially, single-stranded DNA1 and DNA2 were covalently conjugated to the TiNTA and gold nanoparticle (AuNP), respectively. In the presence of cocaine aptamer and glucose, the immobilized DNA1 on the TiNTA and the labeled DNA2 on the AuNP simultaneously hybridized with the adjacent area of the aptamer, and gated the glucose molecules in the nanotubes. Upon the introduction of cocaine, the aptamer specifically reacted with an analyte to form the target–aptamer complex, thus resulting in the dissociation of DNA1–TiNTA and DNA2–AuNP to release glucose molecules from the nanotubes. The as-released glucose molecules could be determined on a personal glucometer (PGM). The experimental results revealed that the PGM signal increased with increasing cocaine concentration, and exhibited a wide linear range of 10–600 nM with a detection limit of 5.2 nM. Intra- and inter-assay relative standard deviations with identical batches were less than 9.3% and 12.7%, respectively. The specificity, reproducibility, and stability of our strategy were acceptable. Importantly, this concept offers promise for a rapid, simple, low-cost, and user-friendly analysis of small-molecular cocaine. [ABSTRACT FROM AUTHOR]

To improve control performances of this combined control system, current construction, control principle and performance of valve-pump parallel control schemes and valve-pump series control schemes were analyzed, then a scheme of valve-pump parallel speed servo with time-sharing variable structure was proposed, its control principle was that control structure varies with speed control requirement, pump and valve time-sharing participate and coordinated control. The scheme includes two types; replenishing and leaking, a valve-pump parallel control hydraulic hoist with time-sharing variable structure in replenishing manner and in leaking manner were developed when the scheme was applied to the hydraulic hoist. Finally, characteristics of the two control manners were also contrastively studied, which would provide basic theory for selection and parameters configuration for valve-pump combined control system. The time-sharing variable structure control scheme establishes a flexible control mechanism that control structure can vary with control requirement in a speed regulating process. It will enrich the control manner of hydraulic servo system, and probably solve the contradiction between efficiency and response of high power hydraulic control system, also gives consideration to the speed stability in stage of start-up. [ABSTRACT FROM AUTHOR]

Objective: To measure imaging data of occipitocervical angle in healthy people at different ages by X-ray., Methods: One hundred and fifty asymptomatic volunteers(75 males and 75 females) aged from 20 and 70 years old with an average of(44.83±13.88) years old were divided into 5 groups according to different ages(20 to 29 years old, 30 to 39 years old, 40 to 49 years old, 50 to 59 years old and 60 to 70 years old), and 30 people in each group. All people underwent lateral radiography of neck on neutral position. McGregor line (the lowest connection line between upper margin of hard palate and occipital scales of plating), occipitocervical angle(OCA) formed by edge of C2 vertebral body, takami's occipitocervical angle formed between connection line of posterior marginal of C2 vertebral body and parallel lines of hard palate were collected. The data were performed statistical analysis according to gender and different ages, and analyzed correlation between OCA and TOCA., Results: OCA of 75 males at different ages were (14.71±3.09)° and(14.22±4.27)° in 75 females. TOCA of 75 males at different ages were (90.50±4.63)° and (90.57±6.67) ° in 75 females. There were no statistical difference in OCA and TOCA in people at different ages( P <0.05). There were no significant meaning among 5 groups at different ages in OCA and TOCA( P >0.05). The relation analysis results showed positive correlation between OCA and TOCA( r =0.454, P <0.01)., Conclusions: The paper provided normal values for occipitocervical angle in population of southwestern China between 20 and 70 years old, and results may be useful for posterior occipitocervical fixation and fusion., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© 2018 by the China Journal of Orthopaedics and Traumatology Press.)

Objective: To compare the hemostatic effect between absorbable hemostatic fluid gelatin (HFG) and absorbable gelatin sponge(GS) during operation of unilateral open-door cervical expansive laminoplasty., Methods: The clinical data of 83 patients underwent unilateral open-door cervical expansive laminoplasty from February 2014 to May 2016 were retrospectively analyzed. According to the used hemostatic materials, patients were divided into two groups. In HFG group, there were 30 males and 11 females, ranging in age from 29 to 81 years, with an average of(55.6±11.6)years; 14 cases were simple cervical spinal stenosis, 9 were cervical spinal stenosis and ossification of posterior longitudinal ligament, and 18 were cervical spinal stenosis complicated with multiple cervical disc herniation. And in GS group, there were 32 males and 10 females, ranging in age from 36 to 78 years, with an average of (55.4±11.1) years; 12 cases were simple cervical spinal stenosis, 10 were cervical spinal stenosis complicated with ossification of posterior longitudinal ligament, and 20 were cervical spinal stenosis complicated with multiple cervical disc herniation. There was no significant difference in the age, gender, and disease categories of patients between two groups ( P >0.05). The operative time, intraoperative bleeding, postoperative drainage, and postoperative complications were compared between two groups., Results: The average operative time, intraoperative bleeding, and postoperative drainage in HFG group were(137.2±30.0) min, (156.1±74.6) ml, and (212.1±67.6) ml, respectively; and in GS group were (154.8±33.5) min, (242.9±120.7) ml, and(303.3±115.5) ml, respectively. There were significantly differences in above items between two groups( P <0.05). No acute heamatoma or related complications was found postoperatively., Conclusions: Compared with GS, HFG can obviously decrease operative time, intraoperative bleeding, and postoperative drainage. It is a safe and effective hemostatic material for the operation of unilateral open-door cervical expansive laminoplasty., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose.