With the advancement of technology and the increase in user demands, gesture recognition played a pivotal role in the field of human-computer interaction. Among various sensing devices, Time-of-Flight (ToF) sensors we...With the advancement of technology and the increase in user demands, gesture recognition played a pivotal role in the field of human-computer interaction. Among various sensing devices, Time-of-Flight (ToF) sensors were widely applied due to their low cost. This paper explored the implementation of a human hand posture recognition system using ToF sensors and residual neural networks. Firstly, this paper reviewed the typical applications of human hand recognition. Secondly, this paper designed a hand gesture recognition system using a ToF sensor VL53L5. Subsequently, data preprocessing was conducted, followed by training the constructed residual neural network. Then, the recognition results were analyzed, indicating that gesture recognition based on the residual neural network achieved an accuracy of 98.5% in a 5-class classification scenario. Finally, the paper discussed existing issues and future research directions.展开更多
While lithium resources are scarce for high energy-dense lithium-ion batteries(LIBs),sodium-ion batteries(SIBs),serving as an alternative,inherently suffer from low capacity and the high-cost use of non-graphite anode...While lithium resources are scarce for high energy-dense lithium-ion batteries(LIBs),sodium-ion batteries(SIBs),serving as an alternative,inherently suffer from low capacity and the high-cost use of non-graphite anodes.Combining Li-and Na-ions within a single battery system is expected to mitigate the shortcomings of both systems while leveraging their respective advantages.In this study,we developed and assembled a nanodiamonds(NDs)-assisted co-Li/Na-ion battery(ND–LSIB).This innovative battery system comprised a commercial graphite anode,an ND-modified polypropylene(DPP)separator,a hybrid lithium/sodium-based electrolyte,and a cathode.It is theoretically and experimentally demonstrated that the ND/Li co-insertion can serve as an ion-drill opening graphite layers and reconstructing graphite anodes into few-layered graphene with expanding interlayer space,achieving highly efficient Li/Na storage and the theoretical maximum of LiC_(6)for Li storage in graphite.In addition,ND is helpful for creating a LiF-/NaF-rich hybrid solid electrolyte interface with improved ionic mobility,mechanical strength,and reversibility.Consequently,ND–LSIBs have higher specific capacities~1.4 times the theoretical value of LIBs and show long-term cycling stability.This study proposes and realizes the concept of Li/Na co-storage in one ion battery with compatible high-performance,cost-effectiveness,and industrial prospects.展开更多
AIM: To evaluate whether postoperative radiotherapy is an alternative to neck lymph node surgery and if it provides a survival benefit for those receiving two-field, chest and abdomen, lymphadenectomy.
In this study, the thermal expansion and heat capacity of San Carlos olivine under high temperature and high pressure are reported. Combining accurate sound velocity data under different P–T conditions with density a...In this study, the thermal expansion and heat capacity of San Carlos olivine under high temperature and high pressure are reported. Combining accurate sound velocity data under different P–T conditions with density and heat capacity data at ambient pressure, the density,adiabatic bulk modulus, shear modulus, and most importantly, thermal expansion and heat capacity, of San Carlos are extracted to 14 GPa by a numerical procedure using classic thermodynamic relationships. These data are in agreement with published findings. To estimate the temperature gradient in the upper mantle, we also report the fitting equations of thermal expansion and heat capacity of San Carlos olivine as a function of both temperature and pressure to the P–T condition of the 410 km discontinuity,which provide the thermodynamic properties with increasing depth in the Earth's interior.展开更多
We performed the pressure calibration to 12 GPa for 14/6 type(octahedron edge length/WC truncated edge length,in mm) cell assembly in DS 6 × 1400 multi-anvil apparatus by using the phase transitions in Bi(Ⅰ-Ⅱ2....We performed the pressure calibration to 12 GPa for 14/6 type(octahedron edge length/WC truncated edge length,in mm) cell assembly in DS 6 × 1400 multi-anvil apparatus by using the phase transitions in Bi(Ⅰ-Ⅱ2.55 GPa,Ⅲ-Ⅴ 7.67 GPa) and ZnTe(LPP-HPP Ⅰ 9.6 GPa,HPP Ⅰ-Ⅱ 12.0 GPa).As verification and application,sound velocity measurements on poly crystalline Al_(2)O_(3) to 12 GPa at room temperature were conducted and the ultrasonic result is in good agreement with previous reports.It demonstrates the feasibility of performing sound velocity measurements close to the mantle transition zone pressure condition in our laboratory.展开更多
In poor minority areas, poor living conditions, single industrial structure and weak public basic services often lead to a deep degree of poverty. This is the most difficult problem to solve in the fight against pover...In poor minority areas, poor living conditions, single industrial structure and weak public basic services often lead to a deep degree of poverty. This is the most difficult problem to solve in the fight against poverty. Yunlong Township, Luquan Yi and Miao Autonomous County, which is located in the alpine canyon area of Jinsha River in China, is a semi-closed agricultural township integrating "nationality, mountain area, poverty and backwardness". Located in the Xinshan Village Committee of this township, Naimu Danxia village group is a typical Lisu settlement. It is a key village group with a deep degree of poverty, and the incidence of poverty is 17.00%. In recent years, Naimu Danxia village group has adhered to the direction of unified promotion, internal and external blood creation and resource integration in the poverty alleviation work of the Lisu nationality in Luquan County. It has successfully taken a road of national unity, self-reliance and common poverty alleviation, and formed a unique poverty alleviation model of "promotion for the entire nationality". At the end of 2018, the incidence of poverty dropped to 0, successfully building a "demonstration village of national unity" at the municipal level in Kunming. Based on the field research and interviews, this paper analyzes and summarizes the specific methods, main achievements, practical experience and popularization and application measures regarding the poverty alleviation model of "promotion for the entire Lisu nationality" in the village group. It tries to provide necessary reference for accurate poverty alleviation and poverty eradication in similar minority areas in Yunnan Province and other provinces.展开更多
目的:对比25G玻璃体切割联合人工晶状体经睫状沟巩膜缝线固定术和无缝线巩膜隧道层间固定术治疗晶状体完全脱位的疗效。方法:回顾性病例对照研究。选取2015-05/2021-09在我院确诊为晶状体完全脱位于玻璃体腔的患者40例40眼,其中行25G玻...目的:对比25G玻璃体切割联合人工晶状体经睫状沟巩膜缝线固定术和无缝线巩膜隧道层间固定术治疗晶状体完全脱位的疗效。方法:回顾性病例对照研究。选取2015-05/2021-09在我院确诊为晶状体完全脱位于玻璃体腔的患者40例40眼,其中行25G玻璃体切割联合人工晶状体经睫状沟巩膜缝线固定术者21眼(缝线组),行25G玻璃体切割联合人工晶状体无缝线巩膜隧道层间固定术者19眼(无缝线组)。随访至术后3mo,观察两组患者手术时间、最佳矫正视力(BCVA)、角膜内皮细胞计数(CECC)、中央角膜厚度(CCT)及术后并发症情况。结果:无缝线组手术用时显著短于缝线组(31.79±6.01min vs 45.38±8.04min,P<0.001)。两组患者术后BCVA均较术前显著改善(均P<0.05),术后1wk无缝线组BCVA(LogMAR)显著优于缝线组(0.32±0.14 vs 0.57±0.25,P<0.001)。术后3mo,两组患者CECC均低于术前(均P<0.01)。缝线组术后1wk CCT大于术前和术后3mo(均P<0.01),无缝线组手术前后CCT无显著变化。随访期间,无缝线组并发症总发生率低于缝线组(26%vs 38%,P>0.05)。结论:25G玻璃体切割联合人工晶状体无缝线巩膜隧道层间固定术治疗晶状体完全脱位手术时间短,术后视力提升快,术后并发症少。展开更多
High-resolution images of human brain are critical for monitoring the neurological conditions in a portable and safe manner.Sound speed mapping of brain tissues provides unique information for such a purpose.In additi...High-resolution images of human brain are critical for monitoring the neurological conditions in a portable and safe manner.Sound speed mapping of brain tissues provides unique information for such a purpose.In addition,it is particularly important for building digital human acoustic models,which form a reference for future ultrasound research.Conventional ultrasound modalities can hardly image the human brain at high spatial resolution inside the skull due to the strong impedance contrast between hard tissue and soft tissue.We carry out numerical experiments to demonstrate that the time-domain waveform inversion technique,originating from the geophysics community,is promising to deliver quantitative images of human brains within the skull at a sub-millimeter level by using ultra-sound signals.The successful implementation of such an approach to brain imaging requires the following items:signals of sub-megahertz frequencies transmitting across the inside of skull,an accurate numerical wave equation solver simulating the wave propagation,and well-designed inversion schemes to reconstruct the physical parameters of targeted model based on the optimization theory.Here we propose an innovative modality of multiscale deconvolutional waveform inversion that improves ultrasound imaging resolution,by evaluating the similarity between synthetic data and observed data through using limited length Wiener filter.We implement the proposed approach to iteratively update the parametric models of the human brain.The quantitative imaging method paves the way for building the accurate acoustic brain model to diagnose associated diseases,in a potentially more portable,more dynamic and safer way than magnetic resonance imaging and x-ray computed tomography.展开更多
The cyclone dust collector is an important subsystem of straw crushers used in agriculture.In the present study,a new type of dust collector with involute morphology is proposed to obtain better dust removal efficienc...The cyclone dust collector is an important subsystem of straw crushers used in agriculture.In the present study,a new type of dust collector with involute morphology is proposed to obtain better dust removal efficiency with respect to that of classical tangential and spiral dust collectors.A discrete phase model(DPM)method is used in synergy with a turbulence model,and the SIMPLE algorithm to simulate the flow field inside the dust collector and the related particle dynamics.It is shown that the internal flow field features a primary swirl,a secondary swirl and blockage effects.Moreover,for the involute dust collector,the tangential velocity in the initial stage and the pressure in the high-pressure area are larger than those obtained for the classical types.The dust removal efficiency is 37.11%,25.3%,and 16.37%for the involute type dust collector,the tangential type and the spiral type,respectively.展开更多
Background Petrochemical products possess a high risk of flammability,explosivity,and toxicity,making petrochemical accidents exceedingly destructive.Therefore,disaster analysis,prediction,and real-time simulations ha...Background Petrochemical products possess a high risk of flammability,explosivity,and toxicity,making petrochemical accidents exceedingly destructive.Therefore,disaster analysis,prediction,and real-time simulations have become important means of controlling and reducing accident hazards.Methods This study proposes a complete real-time simulation solution of gas diffusion with coordinate and concentration data,which was mainly aimed at simulating the types of harmful gas leakage and diffusion accidents in the petrochemical industry.The rendering effect was more continuous and accurate through grid homogenization and trilinear interpolation.This study presents a data processing and rendering parallelization process to enhance simulation efficiency.Gas concentration and fragment transparency were combined to synthesize transparent pixels in a scene.To ensure the approximate accuracy of the rendering effect,improve the efficiency of real-time rendering,and meet the requirement of intuitive perception using concentration data,a weighted blended order-independent transparency(OIT)with enhanced alpha weight is presented,which can provide a more intuitive perception of the hierarchical information of concentration data while preserving depth information.This study compares and analyzes three OIT algorithms-depth peeling,weighted blended OIT,and weighted blended OIT with enhanced alpha weight-in terms of rendering image quality,rendering time,required memory,and hierarchical information.Results Using weighted blended OIT with an enhanced alpha weight technique,the rendering time was shortened by 53.2%compared with that of the depth peeling algorithm,and the texture memory required was significantly smaller than that of the depth peeling algorithm.The rendering results of weighted blended OIT with an enhanced alpha weight were approximately accurate compared with those of the depth peeling algorithm as the ground truth,and there was no popping when surfaces passed through one another.Simultaneously,compared with weighted blended OIT,weighted blended OIT with an enhanced alpha weight achieved an intuitive perception of the hierarchical information of concentration data.展开更多
目的:观察经全视网膜激光光凝(PRP)治疗的重度非增生型糖尿病视网膜病变(NPDR)患者视网膜神经纤维层(RNFL)厚度变化和视野缺失情况及相关性。方法:前瞻性临床研究。选取2017-01/2018-03经我院眼科确诊的重度NPDR患者35例52眼(光凝组,常...目的:观察经全视网膜激光光凝(PRP)治疗的重度非增生型糖尿病视网膜病变(NPDR)患者视网膜神经纤维层(RNFL)厚度变化和视野缺失情况及相关性。方法:前瞻性临床研究。选取2017-01/2018-03经我院眼科确诊的重度NPDR患者35例52眼(光凝组,常规药物治疗的同时行PRP治疗),另选取同期入院、年龄和性别等相匹配的重度NPDR患者35例52眼作为对照组(常规药物治疗)。随访1a,分析比较两组患者最佳矫正视力(BCVA)、RNFL厚度和视野变化情况。结果:治疗后1a,光凝组患者BCVA无明显改善(P>0.05),而对照组BCVA明显降低(P<0.05);光凝组患者颞侧RNFL厚度无明显变化(74.5±13.7μm vs 70.8±11.3μm,P>0.05),其余象限RNFL和平均RNFL厚度均较治疗前变薄(均P<0.05),且颞侧神经纤维对应视野MS值无明显变化(22.5±8.7dB vs 20.8±7.2dB,P>0.05),其余象限和平均MS值均较治疗前降低(均P<0.05)。光凝组患者治疗前后鼻侧、鼻上方、颞上方、颞侧、颞下方、鼻下方及平均RNFL厚度变化值与神经纤维所对应视野MS变化值呈正相关或无相关性。结论:PRP能有效控制重度NPDR进一步发展,维持患者视力,但PRP对RNFL和视野的损伤作用不容忽视。展开更多
目的:观察雷珠单抗辅助玻璃体切割+全视网膜光凝(PRP)+小梁切除术治疗新生血管性青光眼(NVG)的临床疗效。方法:回顾性分析2017-03/2018-10收治的NVG患者44例44眼,采用玻璃体腔内注射雷珠单抗+玻璃体切割+PRP+小梁切除手术治疗的患者22...目的:观察雷珠单抗辅助玻璃体切割+全视网膜光凝(PRP)+小梁切除术治疗新生血管性青光眼(NVG)的临床疗效。方法:回顾性分析2017-03/2018-10收治的NVG患者44例44眼,采用玻璃体腔内注射雷珠单抗+玻璃体切割+PRP+小梁切除手术治疗的患者22例22眼(A组),采用玻璃体腔内注射雷珠单抗+小梁切除+PRP治疗的患者22例22眼(B组)。术后随访6mo,观察患者视力、眼压、眼压控制率、新生血管及并发症等情况。结果:治疗前两组患者眼压无差异(46.2±9.41mmHg vs 49.1±10.15mmHg,P>0.05),治疗后1wk,1、6mo A组患者眼压均低于B组(P<0.05)。治疗后6mo,A组视力、眼压控制率(95%)、新生血管消退情况(91%)均优于B组(P<0.05),但随访期间两组患者并发症发生率无差异(P>0.05)。结论:雷珠单抗辅助玻璃体切割+PRP+小梁切除术治疗NVG安全有效,可稳定持久地控制眼压,改善部分患者视力。展开更多
Abducens nerve palsy（ANP） is commonly seen in patients with diabetes mellitus. The validity of acupuncture as a traditional Chinese medicine method in peripheral nerve repair is well established. However, its effica...Abducens nerve palsy（ANP） is commonly seen in patients with diabetes mellitus. The validity of acupuncture as a traditional Chinese medicine method in peripheral nerve repair is well established. However, its efficacy in randomized controlled trials remains unclear. Herein, we designed a protocol for a prospective, single-center, randomized controlled trial to investigate the effect of intraorbital electroacupuncture on diabetic ANP. We plan to recruit 60 patients with diabetic ANP, and randomly divide them into treatment and control groups. Patients in both groups will continue their glucose-lowering therapy. A neural nutrition drug will be given to both groups for six weeks. The treatment group will also receive intraorbital electroacupuncture therapy. We will assess efficacy of treatment, eyeball movement, diplopia deviation and the levels of fasting blood-glucose and glycosylated hemoglobin before treatment at 2, 4, and 6 weeks after treatment. The efficacy and recurrence will be investigated during follow-up（1 month after intervention）. This protocol was registered at Chinese Clinical Trial Registry on 16 January 2015（Chi CTR-IPR-15005836）. This study was approved by the Ethics Committee of First Affiliated Hospital of Harbin Medical University of China（approval number： 201452）. All protocols will be in accordance with Declaration of Helsinki, formulated by the World Medical Association. Written informed consent will be provided by participants. We envisage that the results of this clinical trial will provide evidence for promoting clinical use of this new therapy for management of ANP.展开更多
Objective and accurate assessment of the degree of ocular motor nerve palsy is helpful not only in the evaluation of prognosis, but also for the screening of treatment methods. However, there is currently no comprehen...Objective and accurate assessment of the degree of ocular motor nerve palsy is helpful not only in the evaluation of prognosis, but also for the screening of treatment methods. However, there is currently no comprehensive measure of its severity. In this study, we designed the Ocular Motor Nerve Palsy Scale and investigated its validity and reliability. Six experts were invited to grade and evaluate the scale. The study recruited 106 patients with a definite diagnosis of unilateral isolated ocular motor nerve palsy. Three physicians evaluated the patients using the scale. One of the three physicians evaluated the patients again after 24 hours. The content validity index（CVI） and factor analysis were used to analyze the scale＇s construct validity. The intraclass correlation coefficient and Cronbach＇s alpha were used to evaluate the inter-rater and test-retest reliability and the internal consistency. The CVI results（I-CVI = 1.0, S-CVI = 0.9, Pc = 0.016, K＊ = 1） indicated good content validity. Factor analysis extracted two common factors that accounted for 85.2% of the variance. Furthermore, the load value of each component was above 0.8, indicating good construct validity. The Ocular Motor Nerve Palsy Scale was found to be highly reliable, with an inter-rater reliability intraclass correlation coefficient of 0.965（P 0.01）, a test-retest reliability intraclass correlation coefficient of 0.976（P 0.01）, and Cronbach＇s alpha values of 0.63–0.70. In conclusion, the Ocular Motor Nerve Palsy Scale with good validity and reliability can be used to quantify the severity of ocular motor nerve palsy. This study was registered at Chinese Clinical Trial Registry（registration number： Chi CTR-OOC-17010702）.展开更多
AIM：To test the therapeutic effects of delayed treatment of mesenchymal stem cells（MSCs） in recurrent experimental autoimmune uveitis（r EAU）.METHODS： The efficacy of different regimens of MSC administration in r...AIM：To test the therapeutic effects of delayed treatment of mesenchymal stem cells（MSCs） in recurrent experimental autoimmune uveitis（r EAU）.METHODS： The efficacy of different regimens of MSC administration in r EAU were tested by evaluation of clinical and pathological intraocular inflammation,as well as retinal structural and functional integrity using optical coherence tomography（OCT） and electroretinogram（ERG）.The retinal sections were also immunostained with antibodies to glial fibrillary acidic protein（GFAP）and rhodopsin（RHO）. RESULTS： Delayed treatment of MSCs effectively alleviated the severity of intraocular inflammation with relative intact of outer retinal structure and function.Moreover,double therapies with longer interval led to an even better clinical evaluation,as well as a trend of decrease in relapse and amelioration of retinal function.MSC therapies also effectively reduced GFAP expression and increased RHO expression in the retina.CONCLUSION： MSC administration can effectively treat developed diseases of rEAU,and multiple therapies can provide additional therapeutic benefits.展开更多
Shell structures have increasingly widespread applications in biomedical ultrasound fields such as contrast agents and drug delivery,which requires the precise prediction of the acoustic radiation force under various ...Shell structures have increasingly widespread applications in biomedical ultrasound fields such as contrast agents and drug delivery,which requires the precise prediction of the acoustic radiation force under various circumstances to improve the system efficiency.The acoustic radiation force exerted by a zero-order quasi-Bessel-Gauss beam on an elastic spherical shell near an impedance boundary is theoretically and numerically studied in this study.By means of the finite series method and the image theory,a zero-order quasi-Bessel-Gauss beam is expanded in terms of spherical harmonic functions,and the exact solution of the acoustic radiation force is derived based on the acoustic scattering theory.The acoustic radiation force function,which represents the radiation force per unit energy density and per unit cross-sectional surface,is especially investigated.Some simulated results for a polymethyl methacrylate shell and an aluminum shell are provided to illustrate the behavior of acoustic radiation force in this case.The simulated results show the oscillatory property and the negative radiation force caused by the impedance boundary.An appropriate relative thickness of the shell can generate sharp peaks for a polymethyl methacrylate shell.Strong radiation force can be obtained at small half-cone angles and the beam waist only affects the results at high frequencies.Considering that the quasi-Bessel-Gauss beam possesses both the energy focusing property and the non-diffracting advantage,this study is expected to be useful in the development of acoustic tweezers,contrast agent micro-shells,and drug delivery applications.展开更多
文摘With the advancement of technology and the increase in user demands, gesture recognition played a pivotal role in the field of human-computer interaction. Among various sensing devices, Time-of-Flight (ToF) sensors were widely applied due to their low cost. This paper explored the implementation of a human hand posture recognition system using ToF sensors and residual neural networks. Firstly, this paper reviewed the typical applications of human hand recognition. Secondly, this paper designed a hand gesture recognition system using a ToF sensor VL53L5. Subsequently, data preprocessing was conducted, followed by training the constructed residual neural network. Then, the recognition results were analyzed, indicating that gesture recognition based on the residual neural network achieved an accuracy of 98.5% in a 5-class classification scenario. Finally, the paper discussed existing issues and future research directions.
基金supported by the National Natural Science Foundation of China(NSFC)(No.52172044)Jilin Provincial Key Research and Development Plan Project(No.20230201151 GX)the Engineering and Physical Sciences Research Council(EPSRC,EP/V027433/3).
文摘While lithium resources are scarce for high energy-dense lithium-ion batteries(LIBs),sodium-ion batteries(SIBs),serving as an alternative,inherently suffer from low capacity and the high-cost use of non-graphite anodes.Combining Li-and Na-ions within a single battery system is expected to mitigate the shortcomings of both systems while leveraging their respective advantages.In this study,we developed and assembled a nanodiamonds(NDs)-assisted co-Li/Na-ion battery(ND–LSIB).This innovative battery system comprised a commercial graphite anode,an ND-modified polypropylene(DPP)separator,a hybrid lithium/sodium-based electrolyte,and a cathode.It is theoretically and experimentally demonstrated that the ND/Li co-insertion can serve as an ion-drill opening graphite layers and reconstructing graphite anodes into few-layered graphene with expanding interlayer space,achieving highly efficient Li/Na storage and the theoretical maximum of LiC_(6)for Li storage in graphite.In addition,ND is helpful for creating a LiF-/NaF-rich hybrid solid electrolyte interface with improved ionic mobility,mechanical strength,and reversibility.Consequently,ND–LSIBs have higher specific capacities~1.4 times the theoretical value of LIBs and show long-term cycling stability.This study proposes and realizes the concept of Li/Na co-storage in one ion battery with compatible high-performance,cost-effectiveness,and industrial prospects.
基金Supported by grant from Doctoral Startup Project of Liaoning Provincial Science and Technology Department,No.20121133
文摘AIM: To evaluate whether postoperative radiotherapy is an alternative to neck lymph node surgery and if it provides a survival benefit for those receiving two-field, chest and abdomen, lymphadenectomy.
基金supported by the Strategic Priority Research Program (B) of Chinese Academy of Sciences (XDB 18010401)Light of the West Foundation of Chinese Academy of Sciences (Y5CR025000)
文摘In this study, the thermal expansion and heat capacity of San Carlos olivine under high temperature and high pressure are reported. Combining accurate sound velocity data under different P–T conditions with density and heat capacity data at ambient pressure, the density,adiabatic bulk modulus, shear modulus, and most importantly, thermal expansion and heat capacity, of San Carlos are extracted to 14 GPa by a numerical procedure using classic thermodynamic relationships. These data are in agreement with published findings. To estimate the temperature gradient in the upper mantle, we also report the fitting equations of thermal expansion and heat capacity of San Carlos olivine as a function of both temperature and pressure to the P–T condition of the 410 km discontinuity,which provide the thermodynamic properties with increasing depth in the Earth's interior.
基金supported by the National Natural Science Foundation of China under Grant No.41873075the West Light Foundation of The Chinese Academy of Sciences。
文摘We performed the pressure calibration to 12 GPa for 14/6 type(octahedron edge length/WC truncated edge length,in mm) cell assembly in DS 6 × 1400 multi-anvil apparatus by using the phase transitions in Bi(Ⅰ-Ⅱ2.55 GPa,Ⅲ-Ⅴ 7.67 GPa) and ZnTe(LPP-HPP Ⅰ 9.6 GPa,HPP Ⅰ-Ⅱ 12.0 GPa).As verification and application,sound velocity measurements on poly crystalline Al_(2)O_(3) to 12 GPa at room temperature were conducted and the ultrasonic result is in good agreement with previous reports.It demonstrates the feasibility of performing sound velocity measurements close to the mantle transition zone pressure condition in our laboratory.
基金Supported by Commissioned by the Project of Office of Rural Work Leading Group of Kunming Municipal Committee of the Communist Party of China"Study on the Poverty Alleviation Model of Kunming City in the Context of World Poverty Reduction"Construction Project of Party Branch Secretary’s Studio of "Double Leader" Teachers in Colleges and Universities of the Ministry of Education of China
文摘In poor minority areas, poor living conditions, single industrial structure and weak public basic services often lead to a deep degree of poverty. This is the most difficult problem to solve in the fight against poverty. Yunlong Township, Luquan Yi and Miao Autonomous County, which is located in the alpine canyon area of Jinsha River in China, is a semi-closed agricultural township integrating "nationality, mountain area, poverty and backwardness". Located in the Xinshan Village Committee of this township, Naimu Danxia village group is a typical Lisu settlement. It is a key village group with a deep degree of poverty, and the incidence of poverty is 17.00%. In recent years, Naimu Danxia village group has adhered to the direction of unified promotion, internal and external blood creation and resource integration in the poverty alleviation work of the Lisu nationality in Luquan County. It has successfully taken a road of national unity, self-reliance and common poverty alleviation, and formed a unique poverty alleviation model of "promotion for the entire nationality". At the end of 2018, the incidence of poverty dropped to 0, successfully building a "demonstration village of national unity" at the municipal level in Kunming. Based on the field research and interviews, this paper analyzes and summarizes the specific methods, main achievements, practical experience and popularization and application measures regarding the poverty alleviation model of "promotion for the entire Lisu nationality" in the village group. It tries to provide necessary reference for accurate poverty alleviation and poverty eradication in similar minority areas in Yunnan Province and other provinces.
文摘目的:对比25G玻璃体切割联合人工晶状体经睫状沟巩膜缝线固定术和无缝线巩膜隧道层间固定术治疗晶状体完全脱位的疗效。方法:回顾性病例对照研究。选取2015-05/2021-09在我院确诊为晶状体完全脱位于玻璃体腔的患者40例40眼,其中行25G玻璃体切割联合人工晶状体经睫状沟巩膜缝线固定术者21眼(缝线组),行25G玻璃体切割联合人工晶状体无缝线巩膜隧道层间固定术者19眼(无缝线组)。随访至术后3mo,观察两组患者手术时间、最佳矫正视力(BCVA)、角膜内皮细胞计数(CECC)、中央角膜厚度(CCT)及术后并发症情况。结果:无缝线组手术用时显著短于缝线组(31.79±6.01min vs 45.38±8.04min,P<0.001)。两组患者术后BCVA均较术前显著改善(均P<0.05),术后1wk无缝线组BCVA(LogMAR)显著优于缝线组(0.32±0.14 vs 0.57±0.25,P<0.001)。术后3mo,两组患者CECC均低于术前(均P<0.01)。缝线组术后1wk CCT大于术前和术后3mo(均P<0.01),无缝线组手术前后CCT无显著变化。随访期间,无缝线组并发症总发生率低于缝线组(26%vs 38%,P>0.05)。结论:25G玻璃体切割联合人工晶状体无缝线巩膜隧道层间固定术治疗晶状体完全脱位手术时间短,术后视力提升快,术后并发症少。
基金Project supported by the Goal-Oriented Project Independently Deployed by Institute of Acoustics,Chinese Academy of Sciences (Grant No.MBDX202113)。
文摘High-resolution images of human brain are critical for monitoring the neurological conditions in a portable and safe manner.Sound speed mapping of brain tissues provides unique information for such a purpose.In addition,it is particularly important for building digital human acoustic models,which form a reference for future ultrasound research.Conventional ultrasound modalities can hardly image the human brain at high spatial resolution inside the skull due to the strong impedance contrast between hard tissue and soft tissue.We carry out numerical experiments to demonstrate that the time-domain waveform inversion technique,originating from the geophysics community,is promising to deliver quantitative images of human brains within the skull at a sub-millimeter level by using ultra-sound signals.The successful implementation of such an approach to brain imaging requires the following items:signals of sub-megahertz frequencies transmitting across the inside of skull,an accurate numerical wave equation solver simulating the wave propagation,and well-designed inversion schemes to reconstruct the physical parameters of targeted model based on the optimization theory.Here we propose an innovative modality of multiscale deconvolutional waveform inversion that improves ultrasound imaging resolution,by evaluating the similarity between synthetic data and observed data through using limited length Wiener filter.We implement the proposed approach to iteratively update the parametric models of the human brain.The quantitative imaging method paves the way for building the accurate acoustic brain model to diagnose associated diseases,in a potentially more portable,more dynamic and safer way than magnetic resonance imaging and x-ray computed tomography.
基金supported by the Independent Research Fund of the State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines(No.SKLMRDPC20ZZ06)and the Program in the Youth Elite Support Plan in Universities of Anhui Province(No.gxyq2020013).
文摘The cyclone dust collector is an important subsystem of straw crushers used in agriculture.In the present study,a new type of dust collector with involute morphology is proposed to obtain better dust removal efficiency with respect to that of classical tangential and spiral dust collectors.A discrete phase model(DPM)method is used in synergy with a turbulence model,and the SIMPLE algorithm to simulate the flow field inside the dust collector and the related particle dynamics.It is shown that the internal flow field features a primary swirl,a secondary swirl and blockage effects.Moreover,for the involute dust collector,the tangential velocity in the initial stage and the pressure in the high-pressure area are larger than those obtained for the classical types.The dust removal efficiency is 37.11%,25.3%,and 16.37%for the involute type dust collector,the tangential type and the spiral type,respectively.
基金Supported by National Key R&D Program of China (2020YFB1710400)。
文摘Background Petrochemical products possess a high risk of flammability,explosivity,and toxicity,making petrochemical accidents exceedingly destructive.Therefore,disaster analysis,prediction,and real-time simulations have become important means of controlling and reducing accident hazards.Methods This study proposes a complete real-time simulation solution of gas diffusion with coordinate and concentration data,which was mainly aimed at simulating the types of harmful gas leakage and diffusion accidents in the petrochemical industry.The rendering effect was more continuous and accurate through grid homogenization and trilinear interpolation.This study presents a data processing and rendering parallelization process to enhance simulation efficiency.Gas concentration and fragment transparency were combined to synthesize transparent pixels in a scene.To ensure the approximate accuracy of the rendering effect,improve the efficiency of real-time rendering,and meet the requirement of intuitive perception using concentration data,a weighted blended order-independent transparency(OIT)with enhanced alpha weight is presented,which can provide a more intuitive perception of the hierarchical information of concentration data while preserving depth information.This study compares and analyzes three OIT algorithms-depth peeling,weighted blended OIT,and weighted blended OIT with enhanced alpha weight-in terms of rendering image quality,rendering time,required memory,and hierarchical information.Results Using weighted blended OIT with an enhanced alpha weight technique,the rendering time was shortened by 53.2%compared with that of the depth peeling algorithm,and the texture memory required was significantly smaller than that of the depth peeling algorithm.The rendering results of weighted blended OIT with an enhanced alpha weight were approximately accurate compared with those of the depth peeling algorithm as the ground truth,and there was no popping when surfaces passed through one another.Simultaneously,compared with weighted blended OIT,weighted blended OIT with an enhanced alpha weight achieved an intuitive perception of the hierarchical information of concentration data.
文摘目的:观察经全视网膜激光光凝(PRP)治疗的重度非增生型糖尿病视网膜病变(NPDR)患者视网膜神经纤维层(RNFL)厚度变化和视野缺失情况及相关性。方法:前瞻性临床研究。选取2017-01/2018-03经我院眼科确诊的重度NPDR患者35例52眼(光凝组,常规药物治疗的同时行PRP治疗),另选取同期入院、年龄和性别等相匹配的重度NPDR患者35例52眼作为对照组(常规药物治疗)。随访1a,分析比较两组患者最佳矫正视力(BCVA)、RNFL厚度和视野变化情况。结果:治疗后1a,光凝组患者BCVA无明显改善(P>0.05),而对照组BCVA明显降低(P<0.05);光凝组患者颞侧RNFL厚度无明显变化(74.5±13.7μm vs 70.8±11.3μm,P>0.05),其余象限RNFL和平均RNFL厚度均较治疗前变薄(均P<0.05),且颞侧神经纤维对应视野MS值无明显变化(22.5±8.7dB vs 20.8±7.2dB,P>0.05),其余象限和平均MS值均较治疗前降低(均P<0.05)。光凝组患者治疗前后鼻侧、鼻上方、颞上方、颞侧、颞下方、鼻下方及平均RNFL厚度变化值与神经纤维所对应视野MS变化值呈正相关或无相关性。结论:PRP能有效控制重度NPDR进一步发展,维持患者视力,但PRP对RNFL和视野的损伤作用不容忽视。
文摘目的:观察雷珠单抗辅助玻璃体切割+全视网膜光凝(PRP)+小梁切除术治疗新生血管性青光眼(NVG)的临床疗效。方法:回顾性分析2017-03/2018-10收治的NVG患者44例44眼,采用玻璃体腔内注射雷珠单抗+玻璃体切割+PRP+小梁切除手术治疗的患者22例22眼(A组),采用玻璃体腔内注射雷珠单抗+小梁切除+PRP治疗的患者22例22眼(B组)。术后随访6mo,观察患者视力、眼压、眼压控制率、新生血管及并发症等情况。结果:治疗前两组患者眼压无差异(46.2±9.41mmHg vs 49.1±10.15mmHg,P>0.05),治疗后1wk,1、6mo A组患者眼压均低于B组(P<0.05)。治疗后6mo,A组视力、眼压控制率(95%)、新生血管消退情况(91%)均优于B组(P<0.05),但随访期间两组患者并发症发生率无差异(P>0.05)。结论:雷珠单抗辅助玻璃体切割+PRP+小梁切除术治疗NVG安全有效,可稳定持久地控制眼压,改善部分患者视力。
基金supported by the National Natural Science Foundation of China,No.81674052the Key Project of Natural Science Foundation of Heilongjiang Province of China,No.ZD201211a grant from the Project of Innovational Scientific Research of Harbin Medical University of China,No.2016LCZX49
文摘Abducens nerve palsy（ANP） is commonly seen in patients with diabetes mellitus. The validity of acupuncture as a traditional Chinese medicine method in peripheral nerve repair is well established. However, its efficacy in randomized controlled trials remains unclear. Herein, we designed a protocol for a prospective, single-center, randomized controlled trial to investigate the effect of intraorbital electroacupuncture on diabetic ANP. We plan to recruit 60 patients with diabetic ANP, and randomly divide them into treatment and control groups. Patients in both groups will continue their glucose-lowering therapy. A neural nutrition drug will be given to both groups for six weeks. The treatment group will also receive intraorbital electroacupuncture therapy. We will assess efficacy of treatment, eyeball movement, diplopia deviation and the levels of fasting blood-glucose and glycosylated hemoglobin before treatment at 2, 4, and 6 weeks after treatment. The efficacy and recurrence will be investigated during follow-up（1 month after intervention）. This protocol was registered at Chinese Clinical Trial Registry on 16 January 2015（Chi CTR-IPR-15005836）. This study was approved by the Ethics Committee of First Affiliated Hospital of Harbin Medical University of China（approval number： 201452）. All protocols will be in accordance with Declaration of Helsinki, formulated by the World Medical Association. Written informed consent will be provided by participants. We envisage that the results of this clinical trial will provide evidence for promoting clinical use of this new therapy for management of ANP.
基金supported by the National Natural Science Foundation of China,No.81674052
文摘Objective and accurate assessment of the degree of ocular motor nerve palsy is helpful not only in the evaluation of prognosis, but also for the screening of treatment methods. However, there is currently no comprehensive measure of its severity. In this study, we designed the Ocular Motor Nerve Palsy Scale and investigated its validity and reliability. Six experts were invited to grade and evaluate the scale. The study recruited 106 patients with a definite diagnosis of unilateral isolated ocular motor nerve palsy. Three physicians evaluated the patients using the scale. One of the three physicians evaluated the patients again after 24 hours. The content validity index（CVI） and factor analysis were used to analyze the scale＇s construct validity. The intraclass correlation coefficient and Cronbach＇s alpha were used to evaluate the inter-rater and test-retest reliability and the internal consistency. The CVI results（I-CVI = 1.0, S-CVI = 0.9, Pc = 0.016, K＊ = 1） indicated good content validity. Factor analysis extracted two common factors that accounted for 85.2% of the variance. Furthermore, the load value of each component was above 0.8, indicating good construct validity. The Ocular Motor Nerve Palsy Scale was found to be highly reliable, with an inter-rater reliability intraclass correlation coefficient of 0.965（P 0.01）, a test-retest reliability intraclass correlation coefficient of 0.976（P 0.01）, and Cronbach＇s alpha values of 0.63–0.70. In conclusion, the Ocular Motor Nerve Palsy Scale with good validity and reliability can be used to quantify the severity of ocular motor nerve palsy. This study was registered at Chinese Clinical Trial Registry（registration number： Chi CTR-OOC-17010702）.
基金Supported by the National Natural Science Foundation of China(No.81371005No.81428012)Tianjin Municipal Science and Technology Commission(No.15JCZDJC35600)
文摘AIM：To test the therapeutic effects of delayed treatment of mesenchymal stem cells（MSCs） in recurrent experimental autoimmune uveitis（r EAU）.METHODS： The efficacy of different regimens of MSC administration in r EAU were tested by evaluation of clinical and pathological intraocular inflammation,as well as retinal structural and functional integrity using optical coherence tomography（OCT） and electroretinogram（ERG）.The retinal sections were also immunostained with antibodies to glial fibrillary acidic protein（GFAP）and rhodopsin（RHO）. RESULTS： Delayed treatment of MSCs effectively alleviated the severity of intraocular inflammation with relative intact of outer retinal structure and function.Moreover,double therapies with longer interval led to an even better clinical evaluation,as well as a trend of decrease in relapse and amelioration of retinal function.MSC therapies also effectively reduced GFAP expression and increased RHO expression in the retina.CONCLUSION： MSC administration can effectively treat developed diseases of rEAU,and multiple therapies can provide additional therapeutic benefits.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.81527901,11604361,and 91630309)。
文摘Shell structures have increasingly widespread applications in biomedical ultrasound fields such as contrast agents and drug delivery,which requires the precise prediction of the acoustic radiation force under various circumstances to improve the system efficiency.The acoustic radiation force exerted by a zero-order quasi-Bessel-Gauss beam on an elastic spherical shell near an impedance boundary is theoretically and numerically studied in this study.By means of the finite series method and the image theory,a zero-order quasi-Bessel-Gauss beam is expanded in terms of spherical harmonic functions,and the exact solution of the acoustic radiation force is derived based on the acoustic scattering theory.The acoustic radiation force function,which represents the radiation force per unit energy density and per unit cross-sectional surface,is especially investigated.Some simulated results for a polymethyl methacrylate shell and an aluminum shell are provided to illustrate the behavior of acoustic radiation force in this case.The simulated results show the oscillatory property and the negative radiation force caused by the impedance boundary.An appropriate relative thickness of the shell can generate sharp peaks for a polymethyl methacrylate shell.Strong radiation force can be obtained at small half-cone angles and the beam waist only affects the results at high frequencies.Considering that the quasi-Bessel-Gauss beam possesses both the energy focusing property and the non-diffracting advantage,this study is expected to be useful in the development of acoustic tweezers,contrast agent micro-shells,and drug delivery applications.
