Objective To analyze the distribution status of the end digits of standardized blood pressure measurement recordings in the clinic and the effectiveness of standardized blood pressure measurement for community hypertension screening. Methods The first visit blood pressure measurement data from the Community Health Service Center in Jing'an District, Shanghai from June 2023 to May 2024 were collected and analyzed. According to different measurement methods, the data were divided into two groups: standardized blood pressure measurement and conventional blood pressure measurement. SPSS 19.0 software was used for data analysis. The differences in the distribution balance of the end digits of blood pressure values and the detection rate of blood pressure elevation between the two different groups were analyzed. Results The frequency range of the end digits of blood pressure recorded values in the standardized pressure measurement group was 9.42% to 10.83%, and the detection rate of elevated blood pressure was 24.89%. The conventional pressure measurement group had a preference of the end digit ^"0^", and the detection rate of elevated blood pressure was only 2.12%. The results of multiple logistic regression analysis showed that gender, age, season, and different blood pressure measurement modes were all influencing factors for the detection rate of elevated blood pressure. Conclusion The standardized blood pressure measurement mode in the clinic is suitable for community hypertension screening and pressure measurement, with higher data quality than the conventional pressure measurement mode.

Objective To establish a simplified simulation method of rocking-chair archwire(RCA),explore the biomechanical effect of RCA during anterior teeth retraction with sliding mechanics,and provide guidance for clinical treatment.Methods A standard 0.019 in×0.025 in(0.483 mm×0.635 mm)labial archwire was imported into ANSYS software and preloaded spring was used to simulate RCA at different angles to achieve parameterized modeling.A three-dimensional(3D)finite element model with labial straight wire appliance,teeth,periodontium and maxillary bone was established to analyze the displacement and force of anterior/posterior teeth under 1.5 N intra-arch traction combined with RCA at different angles.Results Preloading forces of 1.5,3,4.5,and 6 N in spring induced angles of approximately 5°,10°,15°,and 20° for RCA,demonstrating the flexibility and convenience of the parameterized modeling method.During intra-arch traction with increased angle of RCA,lingual crown displacement of the middle incisor gradually decreased,while the lateral incisor and canine showed decreased crown tipping and increased lingual root displacement;when the RCA angle was 20°,the lateral incisor and canine achieved almost bodily retraction.Meanwhile,premolars showed an extrusion tendency,while molars demonstrated distal crown tipping and intrusion tendency.As the RCA angle increased from 0° to 20°,intrusive force on the anterior teeth increased,and the moment-force ratio(M/F)at bracket level increased from 0 to near 9 mm.Conclusions RCA can effectively control the moving pattern of the maxillary anterior teeth and prevent their over-erection and extrusion during retraction with sliding mechanics.During intra-arch traction with rigid stainless steel archwire,theoretically RCA of 20° has sufficient torque control on the anterior teeth to achieve their en-masse retraction.

Objective To establish a simplified simulation method of rocking-chair archwire(RCA),explore the biomechanical effect of RCA during anterior teeth retraction with sliding mechanics,and provide guidance for clinical treatment.Methods A standard 0.019 in×0.025 in(0.483 mm×0.635 mm)labial archwire was imported into ANSYS software and preloaded spring was used to simulate RCA at different angles to achieve parameterized modeling.A three-dimensional(3D)finite element model with labial straight wire appliance,teeth,periodontium and maxillary bone was established to analyze the displacement and force of anterior/posterior teeth under 1.5 N intra-arch traction combined with RCA at different angles.Results Preloading forces of 1.5,3,4.5,and 6 N in spring induced angles of approximately 5°,10°,15°,and 20° for RCA,demonstrating the flexibility and convenience of the parameterized modeling method.During intra-arch traction with increased angle of RCA,lingual crown displacement of the middle incisor gradually decreased,while the lateral incisor and canine showed decreased crown tipping and increased lingual root displacement;when the RCA angle was 20°,the lateral incisor and canine achieved almost bodily retraction.Meanwhile,premolars showed an extrusion tendency,while molars demonstrated distal crown tipping and intrusion tendency.As the RCA angle increased from 0° to 20°,intrusive force on the anterior teeth increased,and the moment-force ratio(M/F)at bracket level increased from 0 to near 9 mm.Conclusions RCA can effectively control the moving pattern of the maxillary anterior teeth and prevent their over-erection and extrusion during retraction with sliding mechanics.During intra-arch traction with rigid stainless steel archwire,theoretically RCA of 20° has sufficient torque control on the anterior teeth to achieve their en-masse retraction.

The retention mechanism of acid drugs such as naproxen, ibuprofen, diclofenac, phenylalanine and 2,4-dichlorophenoxy acetic acid in microemulsion liquid chromatography has been discussed.The reten tion modeling between capacity factors (k') of acid drugs in microemulsion liquid chromatography and concen tration of surfactant, cosurfactant and lipophilic organic solvent and pH value was set.The results showed the effect of change of concentration of surfactant, cosurfactant and lipophilic organic solvent and pH value on capacity factors of acid drugs in microemulsion liquid chromatography was fully consistent with the theoretical modeling.The retention modeling can better reflect the effect of composition of microemulsion solution and pH value on retention behavior of acid drugs in microemulsion liquid chromatography.

The chiral resolution of the optical isomers of aryloxypropionic acid herbicide intermediate α-chloro-N-phenyl propanamide was studied by reversed phase high performance liquid chromatography on chiral column. The experimental results showed that the optical isomers of α-chloro-N-phenyl propanamide could be resolved much better on the tribenzoylcellulose (CTB) chiral column with ethanol as mobile phase. The separation factor and separation degree were 1.52 and 0.60 respectively