HardwareX最新文献_第6页

Design, manufacture, and control of a low-cost positive airway pressure device 设计、制造和控制低成本气道正压装置

IF 2

HardwareX Pub Date : 2024-07-14 DOI: 10.1016/j.ohx.2024.e00559

Jordan F. Hill, Samuel Jackson, Mia Uluilelata, Samrath Sood, Jaimey A. Clifton, Ella F.S. Guy, J. Geoffrey Chase

{"title":"Design, manufacture, and control of a low-cost positive airway pressure device","authors":"Jordan F. Hill, Samuel Jackson, Mia Uluilelata, Samrath Sood, Jaimey A. Clifton, Ella F.S. Guy, J. Geoffrey Chase","doi":"10.1016/j.ohx.2024.e00559","DOIUrl":"10.1016/j.ohx.2024.e00559","url":null,"abstract":"<div><p>Current positive airway pressure devices cost NZ$800-$2500, posing a financial barrier for the estimated 1 billion individuals worldwide with sleep apnea and those researching respiratory diseases. Increasing diagnoses and research interest in the area necessitate a low-cost, easily accessible alternative. Thus, the mePAP, a high-quality, multipurpose, low-cost (∼NZ$250) positive airway pressure device, was designed and prototyped specifically for respiratory disease research, particularly for sleep apnea. The mePAP allows user customization and provides researchers with an affordable tool for testing positive airway pressure algorithms. Unlike typical commercial devices, the mePAP offers adaptability with open-source data collection and easily modifiable software for implementing and analysing different control and diagnostic algorithms. It features three control modes: constant; bilevel; and automatic; and provides pressures from 4 to 20 cmH2O, controlled via a phone app through Wi-Fi, with a mini-sensor added at the mask for increased accuracy. Validation tests showed the mePAP’s performance is comparable to a gold-standard Fisher & Paykel device, with extremely similar output pressures. The mePAP’s low cost enhances accessibility and equity, allowing researchers to test ventilation algorithms for sleep apnea and other respiratory conditions, with all data openly available for analysis. Its adaptability and multiple applications increase its usability and usefulness across various research and clinical settings.</p></div>","PeriodicalId":37503,"journal":{"name":"HardwareX","volume":"19 ","pages":"Article e00559"},"PeriodicalIF":2.0,"publicationDate":"2024-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468067224000531/pdfft?md5=130ec8f76cd631c721efcf941a583181&pid=1-s2.0-S2468067224000531-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141639287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A filling rig for liquid and gas working fluids for two-phase thermal management systems 用于两相热能管理系统的液体和气体工作液的灌装机

IF 2

HardwareX Pub Date : 2024-07-11 DOI: 10.1016/j.ohx.2024.e00558

Colin Butler , Emmanuel Caplanne , Jeff Punch

{"title":"A filling rig for liquid and gas working fluids for two-phase thermal management systems","authors":"Colin Butler , Emmanuel Caplanne , Jeff Punch","doi":"10.1016/j.ohx.2024.e00558","DOIUrl":"10.1016/j.ohx.2024.e00558","url":null,"abstract":"<div><p>Two-phase cooling devices are used to remove and dissipate heat from high power-density electronic systems to maintain them within their operating temperature limits. The manufacture of these devices, such as heat pipes, thermosyphons or vapour chambers, involves firstly removing any internal air or non-condensable gases before charging with the required volume of working fluid. This paper presents detailed designs and operating instructions for a single bench-top station for use in a laboratory environment for the vacuum evacuation, degassing and charging of these devices. Two configurations allow for the filling of fluids which are either liquids or gases at standard temperature and pressure conditions. For liquids, the dispensed volume can be measured directly on an integrated burette, while the method of vapour transfer is used for gases.</p><p>The hardware was demonstrated by filling multiple thermosyphon devices with a number of common working fluids used in two-phase systems, including water, acetone and ammonia. It was shown to deliver precise and repeatable filling volumes with average differences compared to target volumes of 1.7% and 10.5% for liquids and gases respectively. The design is intended to be highly customisable where its size can be modified to accommodate filling volume requirements for different applications.</p></div>","PeriodicalId":37503,"journal":{"name":"HardwareX","volume":"19 ","pages":"Article e00558"},"PeriodicalIF":2.0,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S246806722400052X/pdfft?md5=6666968a2cb2b81f7bd861dece997d67&pid=1-s2.0-S246806722400052X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141630306","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A three-zone hypoxia chamber capable of regulating unique oxygen and carbon dioxide partial pressures simultaneously 三区缺氧室能够同时调节独特的氧气和二氧化碳分压

IF 2

HardwareX Pub Date : 2024-07-11 DOI: 10.1016/j.ohx.2024.e00556

Zachary R. Sitte , Abel A. Miranda , Thomas J. DiProspero , Matthew R. Lockett

{"title":"A three-zone hypoxia chamber capable of regulating unique oxygen and carbon dioxide partial pressures simultaneously","authors":"Zachary R. Sitte , Abel A. Miranda , Thomas J. DiProspero , Matthew R. Lockett","doi":"10.1016/j.ohx.2024.e00556","DOIUrl":"10.1016/j.ohx.2024.e00556","url":null,"abstract":"<div><p>Oxygen is a vital but often overlooked variable in tissue culture experiments. Physiologically relevant oxygen tensions range from partial pressures of 100 mmHg at the alveolar-capillary interface in the lung to less than 7.6 mmHg in the hypoxic regions of solid tumors. These values are markedly lower than the partial oxygen pressure of ambient air, which is standard experimental practice. Physiologically relevant culture environments are needed to better predict cellular and tissue-level responses to drugs or potential toxins. Three commonly used methods to regulate in vitro oxygen tension involve placing cells in 1) a hypoxia chamber, 2) setups that rely on mass transport-limited microenvironments, and 3) microfabricated devices. Hypoxia chambers have the lowest barrier to entry, as they do not require laboratories to change their tissue culture setups. Here, we present a gas-regulation system for a three-zone hypoxia chamber. Each zone can maintain independent environments, with partial pressure compositions of 1–21 % O<sub>2</sub> and 1–10 % CO<sub>2</sub>. The design incorporates small-scale fabrication techniques (e.g., laser cutting and 3D printing) and off-the-shelf electronic components for simple assembly. The hypoxia chambers are significantly lower in cost than the commercial counterparts: $1,400 for the control system or $4,100 for a complete three-zone chamber system<em>.</em></p></div>","PeriodicalId":37503,"journal":{"name":"HardwareX","volume":"19 ","pages":"Article e00556"},"PeriodicalIF":2.0,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468067224000506/pdfft?md5=f5b09c1d42bae109e23b5c3be2c9421e&pid=1-s2.0-S2468067224000506-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141623969","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An open-source membrane stretcher for simultaneous mechanical and structural characterizations of soft materials and biological tissues 用于同时描述软材料和生物组织机械和结构特征的开源膜拉伸器

IF 2

HardwareX Pub Date : 2024-07-09 DOI: 10.1016/j.ohx.2024.e00552

Shannon Li , Alyssa Gee , Nathan Cai , Alexandra Bermudez , Neil Y.C. Lin

{"title":"An open-source membrane stretcher for simultaneous mechanical and structural characterizations of soft materials and biological tissues","authors":"Shannon Li , Alyssa Gee , Nathan Cai , Alexandra Bermudez , Neil Y.C. Lin","doi":"10.1016/j.ohx.2024.e00552","DOIUrl":"10.1016/j.ohx.2024.e00552","url":null,"abstract":"<div><p>The ability to simultaneously measure material mechanics and structure is central for understanding their nonlinear relationship that underlies the mechanical properties of materials, such as hysteresis, strain-stiffening and -softening, and plasticity. This experimental capability is also critical in biomechanics and mechanobiology research, as it enables direct characterizations of the intricate interplay between cellular responses and tissue mechanics. Stretching devices developed over the past few decades, however, do not often allow simultaneous measurements of the structural and mechanical responses of the sample. In this work, we introduce an open-source stretching system that can apply uniaxial strain at a submicron resolution, report the tensile force response of the sample, and be mounted on an inverted microscope for real-time imaging. Our system consists of a pair of stepper-based linear motors that stretch the sample symmetrically, a force transducer that records the sample tensile force, and an optically clear sample holder that allows for high-magnification microscopy. Using polymer samples and cellular specimens, we characterized the motion control accuracy, force measurement robustness, and microscopy compatibility of our stretching system. We envision that this uniaxial stretching system will be a valuable tool for characterizing soft and living materials.</p></div>","PeriodicalId":37503,"journal":{"name":"HardwareX","volume":"19 ","pages":"Article e00552"},"PeriodicalIF":2.0,"publicationDate":"2024-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468067224000464/pdfft?md5=39e23899011f8943be69718e15983488&pid=1-s2.0-S2468067224000464-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141623970","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Low-cost clamp for the measurement of vegetation spectral signatures 测量植被光谱特征的低成本夹具

IF 2

HardwareX Pub Date : 2024-07-07 DOI: 10.1016/j.ohx.2024.e00557

Camilo Acevedo-Correa , Manuel Goez , Maria C. Torres-Madronero , Tatiana Rondon

{"title":"Low-cost clamp for the measurement of vegetation spectral signatures","authors":"Camilo Acevedo-Correa , Manuel Goez , Maria C. Torres-Madronero , Tatiana Rondon","doi":"10.1016/j.ohx.2024.e00557","DOIUrl":"https://doi.org/10.1016/j.ohx.2024.e00557","url":null,"abstract":"<div><p>Spectral signatures allow the characterization of a surface from the reflected or emitted energy along the electromagnetic spectrum. This type of measurement has several potential applications in precision agriculture. However, capturing the spectral signatures of plants requires specialized instruments, either in the field or the laboratory. The cost of these instruments is high, so their incorporation in crop monitoring tasks is not massive, given the low investment in agricultural technology. This paper presents a low-cost clamp to capture spectral leaf signatures in the laboratory and the field. The clamp can be 3D printed using PLA (polylactic acid); it allows the connection of 2 optical fibers: one for a spectrometer and one for a light source. It is designed for ease of use and holds a leave firmly without causing damage, allowing data to be collected with less disturbance. The article compares signatures captured directly using a fiber and the proposed clamp; noise reduction across the spectrum is achieved with the clamp.</p></div>","PeriodicalId":37503,"journal":{"name":"HardwareX","volume":"19 ","pages":"Article e00557"},"PeriodicalIF":2.0,"publicationDate":"2024-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468067224000518/pdfft?md5=bdde53191ce36567b57b60780d139a6b&pid=1-s2.0-S2468067224000518-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141606506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A low-cost and open-hardware portable 3-electrode sleep monitoring device 低成本、开放式硬件的便携式 3电极睡眠监测设备

IF 2

HardwareX Pub Date : 2024-07-06 DOI: 10.1016/j.ohx.2024.e00553

Matías Rodolfo Pretel , Vanessa Vidal , Dante Kienigiel , Cecilia Forcato , Rodrigo Ramele

{"title":"A low-cost and open-hardware portable 3-electrode sleep monitoring device","authors":"Matías Rodolfo Pretel , Vanessa Vidal , Dante Kienigiel , Cecilia Forcato , Rodrigo Ramele","doi":"10.1016/j.ohx.2024.e00553","DOIUrl":"10.1016/j.ohx.2024.e00553","url":null,"abstract":"<div><p>To continue sleep research activities during the lockdown resulting from the COVID-19 pandemic, experiments that were previously conducted in laboratories were shifted to the homes of volunteers. Furthermore, for extensive data collection, it is necessary to use a large number of portable devices. Hence, to achieve these objectives, we developed a low-cost and open-source portable monitor (PM) device capable of acquiring electroencephalographic (EEG) signals using the popular ESP32 microcontroller. The device operates based on instrumentation amplifiers. It also has a connectivity microcontroller with Wi-Fi and Bluetooth that can be used to stream EEG signals. This portable single-channel 3-electrode EEG device allowed us to record short naps and score different sleep stages, such as wakefulness, non rapid eye movement sleep (NREM), stage 1 (S1), stage 2 (S2), stage 3 (S3) and stage 4 (S4). We validated the device by comparing the obtained signals to those generated by a research-grade counterpart. The results showed a high level of accurate similarity between both devices, demonstrating the feasibility of using this approach for extensive and low-cost data collection of EEG sleep recordings.</p></div>","PeriodicalId":37503,"journal":{"name":"HardwareX","volume":"19 ","pages":"Article e00553"},"PeriodicalIF":2.0,"publicationDate":"2024-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468067224000476/pdfft?md5=46945c5c6eda62349cef32f9646d6741&pid=1-s2.0-S2468067224000476-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141639286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Open-source spring-driven syringe pump with 3D-printed components for microfluidic applications 用于微流体应用的带有 3D 打印组件的开源弹簧驱动注射泵

IF 2

HardwareX Pub Date : 2024-07-06 DOI: 10.1016/j.ohx.2024.e00550

Se Been Park , Joong Ho Shin

{"title":"Open-source spring-driven syringe pump with 3D-printed components for microfluidic applications","authors":"Se Been Park , Joong Ho Shin","doi":"10.1016/j.ohx.2024.e00550","DOIUrl":"https://doi.org/10.1016/j.ohx.2024.e00550","url":null,"abstract":"<div><p>The operation of microfluidic devices requires precise and constant fluid flow. Microfluidic systems in low-resource settings require a portable, inexpensive, and electricity-free pumping approach due to the rising demand for microfluidics in point-of-care testing (POCT). Open-source alternatives, employing 3D printing and motors, offer affordability. However, using motors require electrical power, which often relies on external sources, hindering the on-site use of open-source pumps. This study introduces a spring-driven, 3D-printed syringe pump, eliminating the need for an external power source. The syringe pump is operated by the flat spiral spring’s torque. By manually winding up the mainspring, the syringe pump can be operated without electricity. Various flow rates can be achieved by utilizing different syringe sizes and choosing the right gear combinations. All the parts of the syringe pump can be fabricated by 3D printing, requiring no additional components that require electricity. It operates by winding a mainspring and is user-friendly, allowing flow rate adjustments by assembling gears that modulate syringe plunger pushing velocity. The fabrication cost is $25–30 and can be assembled easily by following the instructions. We expect that the proposed syringe pump will enable the utilization of microfluidic technologies in resource-limited settings, promoting the adoption of microfluidics. Detailed information and results are available in the original research paper (https://doi.org/10.1016/j.snb.2024.135289).</p></div>","PeriodicalId":37503,"journal":{"name":"HardwareX","volume":"19 ","pages":"Article e00550"},"PeriodicalIF":2.0,"publicationDate":"2024-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468067224000440/pdfft?md5=c57444183a32adb696c8fceccfd461c6&pid=1-s2.0-S2468067224000440-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141606507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

High-performance wide-band open-source system for acoustic stimulation 用于声学刺激的高性能宽带开源系统

IF 2

HardwareX Pub Date : 2024-07-04 DOI: 10.1016/j.ohx.2024.e00555

Artur Silva , Filipe Carvalho , Bruno F. Cruz

引用次数: 0

A do-it-yourself benchtop device for highly scalable flow synthesis of protein-based nanoparticles 用于高度可扩展的蛋白质纳米粒子流动合成的自助台式设备

IF 2

HardwareX Pub Date : 2024-07-01 DOI: 10.1016/j.ohx.2024.e00554

Egor S. Korenkov , Vladimir R. Cherkasov , Maxim P. Nikitin

{"title":"A do-it-yourself benchtop device for highly scalable flow synthesis of protein-based nanoparticles","authors":"Egor S. Korenkov , Vladimir R. Cherkasov , Maxim P. Nikitin","doi":"10.1016/j.ohx.2024.e00554","DOIUrl":"https://doi.org/10.1016/j.ohx.2024.e00554","url":null,"abstract":"<div><p>Synthesis of nanoparticles is typically carried out in batch procedures, which offer limited control of parameters, and a narrow range of possible batch volumes. In contrast, flow synthesis systems, usually having a microfluidic chip as a crucial part, are devoid of these drawbacks. However, large scale devices – millifluidic systems – may offer several advantages over microfluidic systems, such as easier and cheaper production, enhanced throughput, and reduced channel clogging. Here we report a millifluidic system for the generation of protein nanoparticles, using the flow format of the original swift thermal formation technology (STF), which can process batch volume ranging from 100 µl to any practically significant amount. Capabilities of the system are demonstrated with model synthesis of Epirubicin-encapsulated BSA nanoparticles. A better degree of scalability of the synthesis over batch procedure is shown: with a 10-fold working volume increase, hydrodynamic diameter and loading capacity changed by only 10 % and 1 % respectively, compared to 60 % and 30 % for the batch synthesis. Additionally, we provide all engineering drawings, electrical circuits, programming code and nuances of assembly and operation, so that our findings can be easily reproduced. The ease of construction of the device and the superior characteristics of the resulting nanoparticles compared to the batch method indicate application potential in both the biomedical research and industrial spheres.</p></div>","PeriodicalId":37503,"journal":{"name":"HardwareX","volume":"19 ","pages":"Article e00554"},"PeriodicalIF":2.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468067224000488/pdfft?md5=30d6cd180a9940a8d5dff82c42e16daa&pid=1-s2.0-S2468067224000488-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141595290","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Open SprayBot: A high-throughput paper spray mass spectrometry platform for disease screening 开放喷雾机器人：用于疾病筛查的高通量纸喷雾质谱平台

IF 2

HardwareX Pub Date : 2024-06-30 DOI: 10.1016/j.ohx.2024.e00551

Nancy Shyrley García-Rojas , Héctor Guillén-Alonso , Scott MacKay , Claudia Torres-Calzada , Leonardo Daniel Soto-Rodriguez , Robert Winkler , David S. Wishart

{"title":"The Open SprayBot: A high-throughput paper spray mass spectrometry platform for disease screening","authors":"Nancy Shyrley García-Rojas , Héctor Guillén-Alonso , Scott MacKay , Claudia Torres-Calzada , Leonardo Daniel Soto-Rodriguez , Robert Winkler , David S. Wishart","doi":"10.1016/j.ohx.2024.e00551","DOIUrl":"https://doi.org/10.1016/j.ohx.2024.e00551","url":null,"abstract":"<div><p>Newborn disease screening increases survival, improves quality of life and reduces treatment costs for healthcare systems. Mass spectrometry (MS) is an effective method for metabolic screening. However, conventional analytical methods require biofluid handling and cooling conditions during transport, making the logistics difficult and expensive, especially for remote regions. ’Paper-spray’ (PS) ionization generates a charged solvent spray from samples deposited on paper strips. Therefore, samples can be applied on a suitable matrix and shipped as dried spots to diagnostic laboratories with standard postal or messenger services. We built a robotic platform, the ’Open SprayBot’, to automatically analyze paper-deposited samples via PS-MS and increase the sample throughput. The system is operated via RUMBA32 and Arduino Mega boards. A commercial syringe pump and power supply provide solvent application and electrical current required for PS-MS. The usability of the Open SprayBot was demonstrated by quantifying palmitoyl-l-carnitine, a common biomarker in newborn screening.</p></div>","PeriodicalId":37503,"journal":{"name":"HardwareX","volume":"19 ","pages":"Article e00551"},"PeriodicalIF":2.0,"publicationDate":"2024-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468067224000452/pdfft?md5=a074d019adac06613ad70d177839978c&pid=1-s2.0-S2468067224000452-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141541607","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0