BACKGROUND:Clear aligners,due to their special material properties,are more prone to the"roller coaster effect"during the process of extracting the maxillary first premolar and closing the gap by retracting the anterior teeth,tilting and moving the teeth,leading to deepening of the anterior overjet and opening of the posterior teeth.There are fewer related studies at present concerning whether the thickness or stiffness of the aligner can be changed to reduce the"roller coaster effect"and better control the orthodontic tooth movement,.OBJECTIVE:To analyze the differences in tooth movement control ability of clear aligners of different thicknesses and stiffness when internally retracting maxillary anterior teeth by means of the three-dimensional finite element method.METHODS:Cone beam CT data of patients with convex profile were imported into Mimics and other software to simulate clinical cases.Three-dimensional finite element models were constructed to remove the first premolars,including the maxilla,teeth,and periodontal ligaments,while the diaphragms of clear aligners with thicknesses of 0.50 mm and 0.75 mm were assembled.Four sets of working conditions were created by loading the material properties of two Young's modulus of 1 000 MPa and 2 000 MPa.According to the clinical design to close of the extraction gap,and analyze the distribution of periodontal ligament stress,the displacement trend and the initial displacement of the teeth after loading and calculating in Workbench 2023 R1 software.RESULTS AND CONCLUSION:(1)The Von-Mises stress distribution pattern of periodontal ligament was consistent among the four working conditions,with the maximum value mainly distributed at the cervical part of teeth.The thicker diaphragm of the aligner,the higher the Von-Mises stress;the higher Young's modulus of the aligner,the higher the Von-Mises stress.(2)Under the four working conditions,the overall displacement trend of the maxillary dentition was that the crowns of the anterior teeth moved towards the lingual side and the roots towards the labial side,while the crowns of the posterior teeth moved towards the proximal-medial side and the roots towards the distal-medial side,and it was observed that the crown-root displacements of the teeth were in the opposite direction in all the conditions,and that the displacement of the crowns was greater than the displacement of the roots.Except for canines,the thicker the aligner diaphragm,the lower the R/C value(root-crown displacement ratio);the higher the modulus of elasticity of the aligner diaphragm,the lower the R/C value.(3)The results showed that when the maxillary anterior teeth were internally retracted using invisible aligners,the teeth showed a tendency to tilt and move without incisor torque compensation being designed;the greater the thickness of the aligner and the elastic modulus,the greater the control of the teeth,and the tendency of the teeth to tilt and move decreased;and the cuspids had to be controlled by other auxiliary means.

The principe of electrical impedance tomography(EIT)was described,and the research progress of EIT technology in the field of gesture recognition was reviewed from the aspects of hardware system and gesture recognition algorithm.The challenges of EIT technology applied in the field of gesture recognition were analyzed,and the future development trends were envisioned.[Chinese Medical Equipment Journal,2025,46(4):93-99]

Objective:To investigate the preferences and influencing factors of Traditional Chinese Medicine(TCM)health management services among community healthcare workers,providing a reference for promoting and spreading TCM health management services in communities.Methods:Based on a discrete choice experiment,a questionnaire survey was conducted among 596 community healthcare workers across 9 administrative districts in Beijing.A mixed logit model was used to analyze their preferences.Results:Changes in post-tax monthly income,expected efficacy,single-service duration,technical difficulty,patient compliance,and insurance coverage significantly influenced community doctors'service preferences.Changes in post-tax monthly income had the highest relative importance(35.11%),followed by insurance coverage(34.87%).Preferences varied among healthcare workers with different professional titles,backgrounds,weekly working hours,and whether the service was included in performance evaluations.Conclusion:Both economic and non-economic factors influence community healthcare workers'service preferences to varying degrees.Optimizing the combination of TCM health management service attributes can enhance community healthcare workers'willingness to provide such services.It is recommended to use a combination of economic and non-economic incentive measures and develop differentiated strategies for healthcare workers with different characteristics to meet their service preferences and promote the development of TCM health management services in communities.

Objective:To investigate the preferences and influencing factors of Traditional Chinese Medicine(TCM)health management services among community healthcare workers,providing a reference for promoting and spreading TCM health management services in communities.Methods:Based on a discrete choice experiment,a questionnaire survey was conducted among 596 community healthcare workers across 9 administrative districts in Beijing.A mixed logit model was used to analyze their preferences.Results:Changes in post-tax monthly income,expected efficacy,single-service duration,technical difficulty,patient compliance,and insurance coverage significantly influenced community doctors'service preferences.Changes in post-tax monthly income had the highest relative importance(35.11%),followed by insurance coverage(34.87%).Preferences varied among healthcare workers with different professional titles,backgrounds,weekly working hours,and whether the service was included in performance evaluations.Conclusion:Both economic and non-economic factors influence community healthcare workers'service preferences to varying degrees.Optimizing the combination of TCM health management service attributes can enhance community healthcare workers'willingness to provide such services.It is recommended to use a combination of economic and non-economic incentive measures and develop differentiated strategies for healthcare workers with different characteristics to meet their service preferences and promote the development of TCM health management services in communities.

BACKGROUND:Clear aligners,due to their special material properties,are more prone to the"roller coaster effect"during the process of extracting the maxillary first premolar and closing the gap by retracting the anterior teeth,tilting and moving the teeth,leading to deepening of the anterior overjet and opening of the posterior teeth.There are fewer related studies at present concerning whether the thickness or stiffness of the aligner can be changed to reduce the"roller coaster effect"and better control the orthodontic tooth movement,.OBJECTIVE:To analyze the differences in tooth movement control ability of clear aligners of different thicknesses and stiffness when internally retracting maxillary anterior teeth by means of the three-dimensional finite element method.METHODS:Cone beam CT data of patients with convex profile were imported into Mimics and other software to simulate clinical cases.Three-dimensional finite element models were constructed to remove the first premolars,including the maxilla,teeth,and periodontal ligaments,while the diaphragms of clear aligners with thicknesses of 0.50 mm and 0.75 mm were assembled.Four sets of working conditions were created by loading the material properties of two Young's modulus of 1 000 MPa and 2 000 MPa.According to the clinical design to close of the extraction gap,and analyze the distribution of periodontal ligament stress,the displacement trend and the initial displacement of the teeth after loading and calculating in Workbench 2023 R1 software.RESULTS AND CONCLUSION:(1)The Von-Mises stress distribution pattern of periodontal ligament was consistent among the four working conditions,with the maximum value mainly distributed at the cervical part of teeth.The thicker diaphragm of the aligner,the higher the Von-Mises stress;the higher Young's modulus of the aligner,the higher the Von-Mises stress.(2)Under the four working conditions,the overall displacement trend of the maxillary dentition was that the crowns of the anterior teeth moved towards the lingual side and the roots towards the labial side,while the crowns of the posterior teeth moved towards the proximal-medial side and the roots towards the distal-medial side,and it was observed that the crown-root displacements of the teeth were in the opposite direction in all the conditions,and that the displacement of the crowns was greater than the displacement of the roots.Except for canines,the thicker the aligner diaphragm,the lower the R/C value(root-crown displacement ratio);the higher the modulus of elasticity of the aligner diaphragm,the lower the R/C value.(3)The results showed that when the maxillary anterior teeth were internally retracted using invisible aligners,the teeth showed a tendency to tilt and move without incisor torque compensation being designed;the greater the thickness of the aligner and the elastic modulus,the greater the control of the teeth,and the tendency of the teeth to tilt and move decreased;and the cuspids had to be controlled by other auxiliary means.

Objective To design an 8-channel gene analyzer to take the place of the widely used gene analyzer with problems in inconvenient consumable replacement and short storage time of electrophoresis polymer.Methods The 8-channel gene analyzer had its mechanical components composed of an automatic sample loading table,a polymer injection module,a high-voltage temperature control module,an optical module and an integrated U box,its electrical control system made up of a host computer(an embedded computer)and three slave computers(a sampling control board,a polymer injection control board and a high-voltage temperature control board).The automatic sample loading table involved in four motors and transmission systems for x,y,z directions and optical alignment,the transmission systems adopted mainly belt drive mode and the optical alignment motor had its threads with an anti-backlash structure;the polymer injuection module was manipulated by the polymer injection control board,and the polymer block was made of highly transparent acrylic material;the high-voltage temperature control module realized the regulation of electrophoresis voltage and the detection of electrophoresis current by the low-ripple precision high-voltage power supply,and controlled the temperature of the heating furnace by the proportional-integral-differential(PID)algorithm;the optical module consisted of an excitation module and a light-receiving module,which had the base of the reflector made of low expansion coefficient alloy material;the integrated U box had the electrophoresis polymer,capillary array,polymer block and anode buffer in a plastic housing;the host computer had the data acquisition software programmed with C# and C++,and the slave computers were controlled by STM32 SCM.Results The 8-channel gene analyzer had no significant differences with the widely used ABI3500 gene analyzer in resolution,precision accuracy and clinical results.Conclusion The 8-channel gene analyzer gains advantages in consumable replacement and storage time of electrophoresis polymer,and can meet the requirements for gene sequencing.[Chinese Medical Equipment Journal,2025,46(2):24-30]

The principe of electrical impedance tomography(EIT)was described,and the research progress of EIT technology in the field of gesture recognition was reviewed from the aspects of hardware system and gesture recognition algorithm.The challenges of EIT technology applied in the field of gesture recognition were analyzed,and the future development trends were envisioned.[Chinese Medical Equipment Journal,2025,46(4):93-99]

Objective:To analyze the associated factors and cumulative effects of cardiometabolic multimorbidity (CMM) among residents in southern Xinjiang.Methods:A stratified random cluster sampling method was used to conduct questionnaire surveys, physical examinations and laboratory tests among the personnel of the 51st Brigade, 3rd Division, Xinjiang, in 2016. The multivariate logistic regression, multivariate linear regression, restricted cubic spline, and network analysis methods were used to study the association of lifestyle (smoking, alcohol consumption and physical activity), socioeconomic (occupation, education and marital status) and clinical factors (waist circumference, body mass index and family history) with CMM.Results:A total of 12 773 study subjects were included. The prevalence of cardiovascular metabolic diseases among residents in southern Xinjiang was 52.49%. Specifically, the prevalence rates of dyslipidemia, hypertension, coronary heart disease, diabetes, and stroke were 31.14%, 29.95%, 6.78%, 6.26%, and 2.47%, respectively, and the prevalence of CMM was 19.06%. Multivariate logistic regression analysis revealed that the associations between clinical and socioeconomic factors and CMM significantly increased with higher scores. Specifically, the OR rose from 1.75 (clinical factors) and 1.07 (socioeconomic factors) on a score of 1 to 4.41 and 1.93 on a score of 3, respectively. The association between lifestyle factors and CMM was only observed at higher scores ( OR=1.26, 95% CI:1.07~1.62). The trend test using the scores of each group as continuous variables in the model showed that the risk of disease increased with the accumulation of clinical, socioeconomic and lifestyle factors (all P<0.05). Restricted cubic spline analysis demonstrated a non-linear relationship between the total number of associated factors and CMM ( Poverall<0.05 and Pnon-linear<0.05). Network analysis identified hypertension (strength=0.42) as the “core node” among the five diseases. When analyzing the three types of influencing factors, hypertension (strength=0.68), dyslipidemia (strength=0.47), coronary heart disease (strength=0.37), and clinical factors (strength=0.53) emerged as “core nodes”. In the network of nine associated factors, abnormal waist circumference and BMI (strength=0.90 and 0.84) were identified as “key factors”, while hypertension (strength=0.68) and dyslipidemia (strength=0.52) were identified as “key diseases”. Conclusion:The prevalence of CMM among residents in southern Xinjiang is high, and there is a cumulative effect of multiple factors. Hypertension and dyslipidemia are key diseases in the multimorbidity network, while abnormal BMI and waist circumference are key associated factors.

This study compared the differences in intestinal absorption characteristics of eleven active components in Rubus multibracteatus(RM) extract(protocatechuic acid, tiliroside, scutellarin, luteoloside, astragalin, epicatechin, catechin, xanthotoxin, p-coumaric acid, caffeic acid, and apigenin-7-O-glucuronide) between normal rats and inflammatory pain model rats using the in-vitro everted intestinal sac model. The RM extract was administered at absorption concentrations of 25.0, 50.0, and 100.0 mg·mL~(-1). The contents of the eleven components in intestinal absorption solution samples were quantified by ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS), and their cumulative absorption(Q) and absorption rate constant(K_a) were calculated to evaluate the absorption characteristics of these components in normal rats and inflammatory pain model rats. The results show that except for catechin, epicatechin, and caffeic acid, the cumulative absorption-time curves of the other eight components(protocatechuic acid, tiliroside, scutellarin, luteoloside, astragalin, xanthotoxin, p-coumaric acid, and apigenin-7-O-glucuronide) exhibit an upward trend without saturation, with correlation coefficients(R~2) all > 0.9, indicating linear absorption. However, the overall absorption of all components is not dose-dependent with increasing concentration, suggesting that their absorption mechanisms are not solely passive diffusion. In both normal and model rats, the jejunum shows the highest absorption for all components except xanthotoxin. The overall absorption of seven components(excluding protocatechuic acid, caffeic acid, apigenin-7-O-glucuronide, and luteoloside) in normal rats is better than that in model rats across all intestinal segments. These findings indicate that the pathological state of inflammatory pain alters the intestinal absorption of RM extract, and its mechanism needs further investigation.
Animals ; Rats ; Intestinal Absorption/drug effects* ; Male ; Rats, Sprague-Dawley ; Drugs, Chinese Herbal/metabolism* ; Disease Models, Animal ; Pain/metabolism* ; Intestines/drug effects* ; Intestinal Mucosa/metabolism*

Objective To design an 8-channel gene analyzer to take the place of the widely used gene analyzer with problems in inconvenient consumable replacement and short storage time of electrophoresis polymer.Methods The 8-channel gene analyzer had its mechanical components composed of an automatic sample loading table,a polymer injection module,a high-voltage temperature control module,an optical module and an integrated U box,its electrical control system made up of a host computer(an embedded computer)and three slave computers(a sampling control board,a polymer injection control board and a high-voltage temperature control board).The automatic sample loading table involved in four motors and transmission systems for x,y,z directions and optical alignment,the transmission systems adopted mainly belt drive mode and the optical alignment motor had its threads with an anti-backlash structure;the polymer injuection module was manipulated by the polymer injection control board,and the polymer block was made of highly transparent acrylic material;the high-voltage temperature control module realized the regulation of electrophoresis voltage and the detection of electrophoresis current by the low-ripple precision high-voltage power supply,and controlled the temperature of the heating furnace by the proportional-integral-differential(PID)algorithm;the optical module consisted of an excitation module and a light-receiving module,which had the base of the reflector made of low expansion coefficient alloy material;the integrated U box had the electrophoresis polymer,capillary array,polymer block and anode buffer in a plastic housing;the host computer had the data acquisition software programmed with C# and C++,and the slave computers were controlled by STM32 SCM.Results The 8-channel gene analyzer had no significant differences with the widely used ABI3500 gene analyzer in resolution,precision accuracy and clinical results.Conclusion The 8-channel gene analyzer gains advantages in consumable replacement and storage time of electrophoresis polymer,and can meet the requirements for gene sequencing.[Chinese Medical Equipment Journal,2025,46(2):24-30]