1.Compact Fundus Imaging System Using Shack-Hartmann Wavefront Sensing for High-speed Auto-focus
Zhe-Kai LIN ; Long CHEN ; Geng-Yong ZHENG ; Jin-Tian HUANG ; Jia-Xin DONG ; Shang-Pan YANG ; Wen-Zheng DING ; Ding-An HAN ; Xue-Hua WANG ; Ya-Guang ZENG
Progress in Biochemistry and Biophysics 2026;53(4):1076-1086
ObjectiveThe widespread adoption of portable fundus cameras for primary care and community screening is hindered by limitations in current autofocus(AF) technologies. Image-based methods relying on sharpness evaluation require iterative searches, resulting in slow convergence, while projection-based techniques are susceptible to optical artifacts and calibration errors. To address these challenges, this study introduces a novel AF system based on direct wavefront sensing, designed to deliver simultaneous high speed, high precision, and operational robustness within the compact form factor essential for portable ophthalmic devices. MethodsOur approach fundamentally reimagines the AF process by directly measuring the ocular wavefront aberration. We developed a custom portable fundus camera integrating a miniaturized Shack-Hartmann wavefront sensor (SHWS) into the optical path. An 850 nm laser diode projects a point source onto the retina via oblique illumination to minimize corneal reflections. Light scattered from this spot carries the eye’s refractive error through the imaging optics and is directed to the SHWS, positioned at a plane optically conjugate to the primary color CMOS imaging sensor. A microlens array within the SHWS samples the incident wavefront, generating a pattern of focal spots on a CCD. Real-time centroid analysis of these spots provides a map of local wavefront slopes. These measurements are processed through a singular value decomposition (SVD) algorithm to fit a Zernike polynomial basis set, enabling real-time reconstruction of the wavefront phase. The defocus component (S) is extracted from the second-order Zernike coefficients, providing a direct, quantitative measure of the refractive error in diopters. This value serves as a precise error signal in a closed-loop control system, which commands a voice-coil actuated focusing lens to its null position in a single, deterministic step, eliminating the need for iterative search algorithms. ResultsComprehensive evaluation demonstrated the system’s high performance. Testing on a calibrated model eye (OEMI-7) established a highly linear relationship between the computed defocus S and the focusing lens position across a ±20 Diopter (D) compensation range, achievable within a 5 mm mechanical travel. The system achieved a focusing precision of 0.08 D, corresponding to an 18-fold improvement over a conventional projection spot-size method tested under identical conditions. The total focus acquisition time, encompassing wavefront measurement, computation, and lens actuation, averaged under 0.5 s. Clinical validation with 25 human volunteers (50 eyes, refractive range -15 D to +10 D) confirmed practical efficacy. The wavefront-sensing AF succeeded in 92% of attempts with a mean time of 0.5 s, substantially outperforming a projection-based benchmark which achieved only a 32% success rate with an average time of 4.25 s. The system provided instantaneous directional guidance and maintained stability during minor ocular movements. Objective assessment of image quality, via amplitude contrast of retinal vasculature, showed consistent and significant enhancement following AF correction across the entire tested diopter range. ConclusionThis work successfully implements and validates a direct wavefront-sensing autofocus paradigm for portable fundus cameras. By directly quantifying and compensating for the optical defocus aberration, this method bypasses the fundamental limitations of image-processing and projection-based techniques, enabling rapid, precise, and deterministic diopter compensation. The developed system delivers an exceptional combination of a wide operational range (±20 D), high accuracy (0.08 D), fast convergence (0.5 s), and a compact physical footprint. This technology provides a practical and high-performance focusing solution capable of enhancing the reliability, throughput, and diagnostic utility of portable retinal imaging in large-scale screening applications. Future efforts will be directed towards system cost optimization and performance adaptation for diverse ocular conditions.
2.Cuscutae Semen-Lycii Fructus Improves Spermatogenesis in Rat Model of Oligoasthenozoospermia by Inhibiting Oxidative Stress-induced Blood-testis Barrier Damage via Regulating SIRT1/Nrf2 Signaling Pathway
Wen DUAN ; Xiaojing ZHANG ; Wenjie DING ; Jianning JIN ; Guoqing CHU
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(17):29-38
ObjectiveTo investigate the effect of the herb pair Cuscutae Semen-Lycii Fructus on oxidative stress-induced blood-testis barrier dysfunction and spermatogenesis in the rat model of oligoasthenozoospermia (OAS) and decipher the mechanism based on the silent information regulator 1 (SIRT1)/nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway. MethodsThirty-five male SD rats were randomized into a blank group (n=7) and a modeling group (n=28). The OAS model was established by gavage of hydrocortisone aqueous solution combined with single factor electrical stimulation. The modeled rats were randomly assigned into the following groups: model, Cuscutae Semen-Lycii Fructus granules (3.2 g·kg-1), Cuscutae Semen-Lycii Fructus total flavonoids (0.34 g·kg-1), and L-carnitine (0.38 g·kg-1), and treated for 4 weeks. The sperm quality of rats was assessed by an automatic sperm analyzer. The levels of superoxide dismutase (SOD), malondialdehyde (MAD), and glutathione peroxidase (GSH-Px) in the testicular tissue were determined by enzyme-linked immunosorbent assay. Hematoxylin-eosin staining was employed to reveal the pathological changes in the testicular tissue and score the spermatogenic function. Transmission electron microscopy was employed to observe the ultrastructural changes of Sertoli cells. Western blot and Real-time PCR were employed to determine the protein and mRNA levels, respectively, of SIRT1, Nrf2, Occludin, zonula occludens-1 (ZO-1), connexin 43 (CX43), and β-catenin. ResultsCompared with the blank group, the model group showed decreased total sperm count and motility (P<0.05, P<0.01), obvious damage in the testicular tissue and blood-testis barrier structure, reduced score of spermatogenic function (P<0.01), declined levels of GSH-Px and SOD in the testicular tissue (P<0.05), elevated level of MDA, and down-regulated protein levels of SIRT1, Nrf2, ZO-1, CX43, β-catenin, and occludin (P<0.05, P<0.01) and mRNA levels of SIRT1, Nrf2, ZO-1, CX43, and β-catenin in the testicular tissue (P<0.05, P<0.01). After treatment, the testicular tissue, blood-testis barrier structure, and score of spermatogenic function (P<0.01) were improved in the Cuscutae Semen-Lycii Fructus granules group, Cuscutae Semen-Lycii Fructus total flavonoids group, and L-carnitine group. Compared with the model group, the treatment groups presented lowered levels of GSH-Px and SOD (P<0.05, P<0.01), and the Cuscutae Semen-Lycii Fructus granule group showed a decline in MDA level. The protein and mRNA levels of SIRT1, Nrf2, ZO-1, CX43, β-catenin, and occludin were up-regulated in the Cuscutae Semen-Lycii Fructus granules group and total flavonoids group (P<0.05, P<0.01). ConclusionThe herb pair Cuscutae Semen-Lycii Fructus can regulate the SIRT1/Nrf2 pathway to inhibit oxidative stress and alleviate the blood-testis barrier damage, thereby improving the spermatogenic function in the rat model of OAS. Total flavonoids may be the material basis for the therapeutic effect of Cuscutae Semen-Lycii Fructus.
3.Ion Unidirectional Ejection Simulation Study of An Extremely Miniature Hyperbolic Linear Ion Trap
Yun-Fan HE ; Zhuo-Qing YANG ; Yan WANG ; Jiu-Wen SUN ; Yun-Na SUN ; Lu-Yue ZHU ; Di ZHANG ; Feng-Dan WANG ; Min LIU ; Gui-Fu DING ; Jin-Yuan YAO
Chinese Journal of Analytical Chemistry 2025;53(6):885-893
With the increasing demand for dynamic,real-time and rapid qualitative analysis of chemical composition in areas such as emergency response and space exploration,chip-scale mass spectrometers have attracted significant attention.These devices are expected to drive the integration of mass spectrometry with micro/nano-fabrication and intelligent sensing technologies,fostering profound innovation and breakthroughs in analytical chemistry.As an excellent mass analyzer,the ion trap exhibits numerous advantages,and its miniaturization creates favorable conditions for the high-density integration of miniature mass spectrometers.However,the reduction in ion storage capacity may compromise its sensitivity and dynamic range,rendering the study of ion unidirectional ejection in highly miniaturized ion traps of significant practical importance.In this work,a research was conducted on achieving efficient ion unidirectional ejection while maintaining high mass resolution in the extremely miniature hyperbolic linear ion trap(M-HLIT)with a field radius of 1 mm,and an electric field compensation method was proposed,which combined asymmetric electrode stretching and unbalanced RF voltage to achieve high-precision optimization of the electric field composition.Simulations showed that in an ideal structure,this method achieved 100%unidirectional ejection efficiency with the mass resolution of 518,significantly outperforming traditional asymmetric structure method(365)and unbalanced voltage method(321).Following the introduction of ion ejection slots,further optimization through bidirectional stretching and electrical parameters improved the resolution to 790 while maintaining a unidirectional ejection efficiency of 93%.This method eliminated the requirement for additional excitation voltage,offering an ideal solution for the miniature mass analyzer with high detection performance of chip-level mass spectrometers.
4.Cuscutae Semen-Lycii Fructus Improves Spermatogenesis in Rat Model of Oligoasthenozoospermia by Inhibiting Oxidative Stress-induced Blood-testis Barrier Damage via Regulating SIRT1/Nrf2 Signaling Pathway
Wen DUAN ; Xiaojing ZHANG ; Wenjie DING ; Jianning JIN ; Guoqing CHU
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(17):29-38
ObjectiveTo investigate the effect of the herb pair Cuscutae Semen-Lycii Fructus on oxidative stress-induced blood-testis barrier dysfunction and spermatogenesis in the rat model of oligoasthenozoospermia (OAS) and decipher the mechanism based on the silent information regulator 1 (SIRT1)/nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway. MethodsThirty-five male SD rats were randomized into a blank group (n=7) and a modeling group (n=28). The OAS model was established by gavage of hydrocortisone aqueous solution combined with single factor electrical stimulation. The modeled rats were randomly assigned into the following groups: model, Cuscutae Semen-Lycii Fructus granules (3.2 g·kg-1), Cuscutae Semen-Lycii Fructus total flavonoids (0.34 g·kg-1), and L-carnitine (0.38 g·kg-1), and treated for 4 weeks. The sperm quality of rats was assessed by an automatic sperm analyzer. The levels of superoxide dismutase (SOD), malondialdehyde (MAD), and glutathione peroxidase (GSH-Px) in the testicular tissue were determined by enzyme-linked immunosorbent assay. Hematoxylin-eosin staining was employed to reveal the pathological changes in the testicular tissue and score the spermatogenic function. Transmission electron microscopy was employed to observe the ultrastructural changes of Sertoli cells. Western blot and Real-time PCR were employed to determine the protein and mRNA levels, respectively, of SIRT1, Nrf2, Occludin, zonula occludens-1 (ZO-1), connexin 43 (CX43), and β-catenin. ResultsCompared with the blank group, the model group showed decreased total sperm count and motility (P<0.05, P<0.01), obvious damage in the testicular tissue and blood-testis barrier structure, reduced score of spermatogenic function (P<0.01), declined levels of GSH-Px and SOD in the testicular tissue (P<0.05), elevated level of MDA, and down-regulated protein levels of SIRT1, Nrf2, ZO-1, CX43, β-catenin, and occludin (P<0.05, P<0.01) and mRNA levels of SIRT1, Nrf2, ZO-1, CX43, and β-catenin in the testicular tissue (P<0.05, P<0.01). After treatment, the testicular tissue, blood-testis barrier structure, and score of spermatogenic function (P<0.01) were improved in the Cuscutae Semen-Lycii Fructus granules group, Cuscutae Semen-Lycii Fructus total flavonoids group, and L-carnitine group. Compared with the model group, the treatment groups presented lowered levels of GSH-Px and SOD (P<0.05, P<0.01), and the Cuscutae Semen-Lycii Fructus granule group showed a decline in MDA level. The protein and mRNA levels of SIRT1, Nrf2, ZO-1, CX43, β-catenin, and occludin were up-regulated in the Cuscutae Semen-Lycii Fructus granules group and total flavonoids group (P<0.05, P<0.01). ConclusionThe herb pair Cuscutae Semen-Lycii Fructus can regulate the SIRT1/Nrf2 pathway to inhibit oxidative stress and alleviate the blood-testis barrier damage, thereby improving the spermatogenic function in the rat model of OAS. Total flavonoids may be the material basis for the therapeutic effect of Cuscutae Semen-Lycii Fructus.
5.Spatial-temporal distribution characteristics of an animal plague epidemic in marmot foci in the Qilian-Altun Mountains of Gansu Province,2014-2023
Ding-sheng WANG ; Xiao-jie ZHOU ; Wen-jing AN ; Jin-xiao XI ; Da-qin XU ; Li-min GUO
Chinese Journal of Zoonoses 2025;41(6):668-674
This study was analyzed the spatial-temporal distribution and aggregation characteristics of Yersinia pestispositive host animals and vector pathogens in marmot natural foci in the Qilian-Altun mountains,Gansu Province,to provide a scientific basis for precise plague prevention and control.Y.pestissurveillance data for marmot natural foci in Qilian-Altun Mountains of Gansu Province from 2014 to 2023 were obtained from the Disease Control and Prevention Center of Gansu Province.Origin 2024 software was used for data visualization and presentation.Global and local spatial autocorrelation analyses and trend analyses were conducted in ArcGIS 10.8 software,with townships as the spatial scale.Cumulatively,440 strains of Y.pestis were isolated from the natural marmot foci in the Qilian-Altun mountainsof Gansu Province from 2014 to 2023.Most strains was isolated from marmots(345 strains,78.41%),and the remainder were isolated from vectors.Temporal distribution analysis indicated that the highest number of detected bacteria was reported in July and August(both 121 strains,27.50%).Regional distribution analysis revealed that Aksai County reported the highest number of detected bacteria(255 strains,57.95%).Global spatial autocorrelation analysis showed a spatially clustered distribution of the number of bacteria detected annually in the townships containing natural foci,except in2014,2016,and 2021-2023.The strongest spatial clustering was observed in 2020(Moran's I=0.521 2,Z=14.397 0,P<0.001).Local spatial autocorrelation analysis indicated a"high-high"aggregation area in the natural foci every year from 2014 to 2023,primarily in Hongliuwan Town of Aksai County and Dangchengwan Town of Subei County.The distribution of the"low-low"aggregation area was essentially consistent with the low activity area of the Yersinia pestisepidemic.The trend in annual total bacterial count gradually increased from east to west,and peaked in the western part of the epidemic focus.Clear spatial aggregation characteristics of the number of Y.pestis were detected in the marmot natural foci in the Qilian-Altun mountains at the townshiplevel as a whole in Gansu Province from 2014 to 2023.The aggregation area was mainly in the western section of Qilian Mountain to the Altun mountain section of the epidemic source area.Monitoring and prevention and control efforts should be focused in this key area,with prevention and control measures tailored to the local conditions,and classified guidance to decrease the risk of plague occurrence and spread.
6.Estimate the Age of Han Adult Based on the Pulp Chamber Volume and Pulp Dentinal Index of Right First Molars Using Oral and Maxillofacial CBCT
Yan-Jie DING ; Xiao ZHANG ; Wen-Li SHI ; Zi-Yi LI ; Wei WANG ; Shi-Lin ZHANG ; Gen-Jie YANG ; A-Ji GUO ; Bo JIN
Journal of Forensic Medicine 2025;41(1):59-65
Objective To explore the correlation between the actual age and the pulp chamber volume(PCV)and pulp dentinal index(PDI)of the right first molars based on cone beam computed tomog-raphy(CBCT)technology,and to construct an accurate and convenient model for age estimation.Methods CBCT image data of 1 857 Han adults(883 males and 974 females)from the Department of Stomatology,Affiliated Hospital of North Sichuan Medical College were collected.The data were di-vided into training and validation sets at a ratio of 8∶2.A total of 1 485 training samples were used to construct the age estimation model,and 372 samples were used to validate the accuracy of the model.The Mimics 21.0 software was used to measure the PCV and calculate the PDI of the right first molars.Their correlations with age and the differences between different sexes and tooth positions were analyzed.Results Both the PCV and the PDI of the first molars showed strong negative correla-tions with the actual age(r values ranged from 0.82 to 0.89).The differences in PCV and PDI be-tween different sexes and tooth positions were statistically significant(P<0.05).The age estimation model based on PDI was superior to that based on PCV.The model based on the PDI values of the two right first molars(y=73.72-44.15 x3-28.27 x4,where x3 and x4 are the PDI values of the right maxil-lary and mandibular first molars,respectively)was the best,with the R2 of 0.79 and the mean abso-lute error of 4.90 years.Conclusion Both PCV and PDI of the first molars are effective indicators for age estimation.The age estimation model based on the PDI is more convenient and accurate than that based on the PCV,providing a more effective method for age estimation in forensic practice.
7.Spatial-temporal distribution characteristics of an animal plague epidemic in marmot foci in the Qilian-Altun Mountains of Gansu Province,2014-2023
Ding-sheng WANG ; Xiao-jie ZHOU ; Wen-jing AN ; Jin-xiao XI ; Da-qin XU ; Li-min GUO
Chinese Journal of Zoonoses 2025;41(6):668-674
This study was analyzed the spatial-temporal distribution and aggregation characteristics of Yersinia pestispositive host animals and vector pathogens in marmot natural foci in the Qilian-Altun mountains,Gansu Province,to provide a scientific basis for precise plague prevention and control.Y.pestissurveillance data for marmot natural foci in Qilian-Altun Mountains of Gansu Province from 2014 to 2023 were obtained from the Disease Control and Prevention Center of Gansu Province.Origin 2024 software was used for data visualization and presentation.Global and local spatial autocorrelation analyses and trend analyses were conducted in ArcGIS 10.8 software,with townships as the spatial scale.Cumulatively,440 strains of Y.pestis were isolated from the natural marmot foci in the Qilian-Altun mountainsof Gansu Province from 2014 to 2023.Most strains was isolated from marmots(345 strains,78.41%),and the remainder were isolated from vectors.Temporal distribution analysis indicated that the highest number of detected bacteria was reported in July and August(both 121 strains,27.50%).Regional distribution analysis revealed that Aksai County reported the highest number of detected bacteria(255 strains,57.95%).Global spatial autocorrelation analysis showed a spatially clustered distribution of the number of bacteria detected annually in the townships containing natural foci,except in2014,2016,and 2021-2023.The strongest spatial clustering was observed in 2020(Moran's I=0.521 2,Z=14.397 0,P<0.001).Local spatial autocorrelation analysis indicated a"high-high"aggregation area in the natural foci every year from 2014 to 2023,primarily in Hongliuwan Town of Aksai County and Dangchengwan Town of Subei County.The distribution of the"low-low"aggregation area was essentially consistent with the low activity area of the Yersinia pestisepidemic.The trend in annual total bacterial count gradually increased from east to west,and peaked in the western part of the epidemic focus.Clear spatial aggregation characteristics of the number of Y.pestis were detected in the marmot natural foci in the Qilian-Altun mountains at the townshiplevel as a whole in Gansu Province from 2014 to 2023.The aggregation area was mainly in the western section of Qilian Mountain to the Altun mountain section of the epidemic source area.Monitoring and prevention and control efforts should be focused in this key area,with prevention and control measures tailored to the local conditions,and classified guidance to decrease the risk of plague occurrence and spread.
8.Survey of foot care knowledge and behavioral status among type 2 diabetes patients in a community in Beijing and its influencing factors
Gaoqiang LI ; Qian LU ; Bing WEN ; Xin QI ; Hui GUAN ; Huijuan LI ; Jin LIU ; Yanming DING
Journal of Clinical Medicine in Practice 2024;28(7):133-137
Objective To investigate the knowledge and behavioral status of foot care among patients with type 2 diabetes in Xinjiekou Community in Beijing and analyze its influencing factors. Methods A convenient sampling method was used to select 278 diabetes patients from Xinjiekou Community in Beijing for questionnaire surveys, which included general information, foot care knowledge, and behaviors of the patients. Results The average score of foot care knowledge among the 278 patients was (71.65±14.59), indicating a moderate level overall. The average score of foot care behavior was (48.83±8.83), indicating a poor level overall. Multivariate stepwise regression analysis showed that gender, duration of diabetes, and whether the patients had received foot care education or not were independent influencing factors for both the foot care knowledge score and the foot care behavior score among community diabetes patients (
9.Development and prospects of predicting drug polymorphs technology
Mei GUO ; Wen-xing DING ; Bo PENG ; Jin-feng LIU ; Yi-fei SU ; Bin ZHU ; Guo-bin REN
Acta Pharmaceutica Sinica 2024;59(1):76-83
Most chemical medicines have polymorphs. The difference of medicine polymorphs in physicochemical properties directly affects the stability, efficacy, and safety of solid medicine products. Polymorphs is incomparably important to pharmaceutical chemistry, manufacturing, and control. Meantime polymorphs is a key factor for the quality of high-end drug and formulations. Polymorph prediction technology can effectively guide screening of trial experiments, and reduce the risk of missing stable crystal form in the traditional experiment. Polymorph prediction technology was firstly based on theoretical calculations such as quantum mechanics and computational chemistry, and then was developed by the key technology of machine learning using the artificial intelligence. Nowadays, the popular trend is to combine the advantages of theoretical calculation and machine learning to jointly predict crystal structure. Recently, predicting medicine polymorphs has still been a challenging problem. It is expected to learn from and integrate existing technologies to predict medicine polymorphs more accurately and efficiently.
10.Laser Ablation Inductively Coupled Plasma Mass Spectrometry Analysis of Multilayer Thin Film Thickness of PbS Quantum Dot Photovoltaic Devices
Ding-Wen ZHANG ; Hui-Lai LI ; Fan LI ; Wei GUO ; Lan-Lan JIN ; Sheng-Hong HU
Chinese Journal of Analytical Chemistry 2024;52(10):1609-1618
Accurate determination of the thickness of multi-layered nanofilm materials is of great importance to advance the development of thin film deposition technology and ensure the quality assurance of photovoltaic materials.Laser ablation inductively coupled plasma mass spectrometry(LA-ICP-MS)has been successfully employed for depth profiling of thin film materials,such as metal coatings.However,the accuracy of interface discrimination and thin layer thickness measurement is limited by the mixing effects of elemental signals.In this work,a high-depth resolution method for measuring the thin film thickness of lead sulfide(PbS)colloidal quantum dot(CQD)photovoltaic devices by LA-ICP-MS was introduced.The influence of different laser parameters on the mixing effects of element signals during the ablation process was compared,and the results showed that the laser ablation behavior of multi-layered nanofilm materials were improved and the mixing of element signals were reduced by optimizing parameters such as laser energy density and spot diameter.Meanwhile,a self-developed aerosol rapid wash-out small volume tubular ablation cell was used to effectively improve the aerosol transport efficiency,and the wash-out time of aerosol was(1.60±0.6)s.Compared with commercial cylindrical ablation cells,the depth profile of multi-layer thin film samples was clearer.The depth profile of the interlayer interface showed a significant melting phenomenon during the ablation of the PbS CQD layer,leading to severe mixing of elemental signals at the PbS/ZnO layer interface.Under the conditions such as 2.5 J/cm2 laser energy,32 μm spot diameter,and 1 Hz repetition rate,the average ablation rates of Au,PbS and ZnO layers in PbS CQD photovoltaic devices were(60±2)nm/pulse,(69±5)nm/pulse,and(22±2)nm/pulse,with depth resolution of(26±2)nm,(213±11)nm,and(68±6)nm,respectively.The thickness of PbS CQD photovoltaic device films from the same batch was determined,and the test results exhibited good consistency with scanning electron microscope(SEM)measurement values,with a relative deviation of less than 6%.This method could accurately determine the thickness of nanoscale multilayer thin film samples,which was crucial for improving the performance of photovoltaic devices and controlling product quality.


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