- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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ZnO Nanosheets Modified with Graphene Quantum Dots and SnO2 Quantum Nanoparticles for Room-Temperature H2S Sensing
摘要： Overcoming the low selectivity issue of semiconductor oxide (SMO)-based gas sensors at room temperature and realizing the accurate detection of trace disease biomarkers are highly desirable for widespread deployments of sensors in exhaled breath. Here, a self-assembly strategy is proposed to create a graphene quantum dot (GQD) functionalized porous and hierarchical SnO2 quantum nanoparticles (SnO2QNP)/ZnO nanostructure. SnO2QNP/ZnO nanosheets self-assembled directly on the digital integrated electrodes with a post-synthetic humidity treatment (psHT), the construction of GQD and SnO2QNP loaded ZnO nanosheet heterostructure is highly controllable and reproducible. The strong synergistic effect and p-n heterojunction between the p-type GQD and n-type SnO2 and ZnO effectively enlarged the resistance variation due to the change in oxygen adsorption. In comparison with pristine ZnO and SnO2/ZnO sensors, the GQD modified hierarchical SnO2QNP/ZnO nanostructure exhibited a remarkably high response (S=15.9 for 0.1 ppm H2S) and rapid response/recovery time (14/13s), and good selectivity towards H2S against other interfering gases. In particular, we applied principal component analysis (PCA) to analyze the sensing performance of GQD-SnO2QNP/ZnO sensor and found that the combined effects of GQD/SnO2QNP/ZnO heterointerfaces contributed to the improvement of selectivity of sensors. The results demonstrate that the GQD modified SMO with the hierarchical structure has a high potential in the non-invasive exhaled diagnosis.
关键词： graphene quantum dot,principal component analysis,exhaled diagnosis,gas sensor,zinc oxide nanosheet,tin dioxide quantum nanoparticle
更新于2025-09-23 15:21:01
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Photoacoustic imaging for monitoring periodontal health: A first human study
摘要： The gold-standard periodontal probe is an aging tool that can detect periodontitis and monitor gingival health but is highly error-prone, does not fully characterize the periodontal pocket, and causes pain. Photoacoustic imaging is a noninvasive technique that can address these limitations. Here, a range of ultrasound frequencies between 16-40 MHz were used to image the periodontium and a contrast medium based on cuttlefish ink was used to label the pockets. A 40 MHz ultrasound frequency could spatially resolve the periodontal anatomy, including tooth, gum, gingival margin, and gingival thickness of tooth numbers 7-10 and 22-27. The photoacoustic-ultrasound measurements were more precise (0.01 mm) than those taken with physical probes by a dental hygienist. Furthermore, the full geometry of the pockets could be visualized with relative standard deviations of 10% (n = 5). This study shows the potential for non-invasive monitoring of periodontal health with photoacoustic-ultrasound imaging in the dental clinic.
关键词： periodontal disease,gingival thickness,periodontal charting,Photoacoustic imaging,melanin nanoparticles,diagnosis,pocket depth
更新于2025-09-23 15:21:01
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A Photovoltaic Array Fault Diagnosis Method Considering the Photovoltaic Output Deviation Characteristics
摘要： There are a large number of photovoltaic (PV) arrays in large-scale PV power plants or regional distributed PV power plants, and the output of different arrays fluctuates with the external conditions. The deviation and evolution information of the array output are easily covered by the random fluctuations of the PV output, which makes the fault diagnosis of PV arrays difficult. In this paper, a fault diagnosis method based on the deviation characteristics of the PV array output is proposed. Based on the current of the PV array on the DC (direct current) side, the deviation characteristics of the PV array output under different arrays and time series are analyzed. Then, the deviation function is constructed to evaluate the output deviation of the PV array. Finally, the fault diagnosis of a PV array is realized by using the probabilistic neural network (PNN), and the effectiveness of the proposed method is verified. The main contributions of this paper are to propose the deviation function that can extract the fault characteristics of PV array and the fault diagnosis method just using the array current which can be easily applied in the PV plant.
关键词： photovoltaic array,deviation characteristics,fault diagnosis,probabilistic neural network
更新于2025-09-23 15:21:01
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[Methods in Molecular Biology] Microfluidic Electrophoresis Volume 1906 (Methods and Protocols) || Paper-Based Electrophoresis Microchip as a Powerful Tool for Bioanalytical Applications
摘要： This chapter describes the development of paper-based microchip electrophoresis (pME) devices for the separation of clinically relevant compounds. pME were fabricated by laser cut and thermal lamination process using polyester pouches. In addition, hand-drawn pencil electrodes were integrated to the device to perform capacitively coupled contactless conductivity detection (C4D). Finished device costs less than US$ 0.10 and did not require either sophisticated instrumentation or clean room facilities. Furthermore, pME is lightweight, easy to handle, ?exible, and robust. pME-C4D device revealed an excellent capacity to separate BSA and creatinine in less than 150 s with baseline resolution. The device proposed in this chapter has proven to be a good alternative as a platform for the diagnosis of diseases from renal disorders such as diabetes mellitus and heart disease.
关键词： Biomolecules,Paper electrophoresis,Kidney failure,Pencil electrodes,Bovine serum albumin,Creatinine,Clinical diagnosis,Contactless conductivity detection
更新于2025-09-23 15:21:01
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Rapid and Low-Cost Detection of Thyroid Dysfunction Using Raman Spectroscopy and an Improved Support Vector Machine
摘要： This study presents a rapid and low-cost method to detect thyroid dysfunction using serum Raman spectroscopy combined with support vector machine (SVM). The serum samples taken from 34 thyroid dysfunction patients and 40 healthy volunteers were measured in this study. Tentative assignments of the Raman bands in the measured serum spectra suggested specific biomolecular changes between the groups. Principal component analysis (PCA) was used for feature extraction and reduced the dimension of high-dimension spectral data; then, SVM was employed to establish an effective discriminant model. To improve the efficiency and accuracy of the SVM discriminant model, we proposed artificial fish coupled with uniform design (AFUD) algorithm to optimize the SVM parameters. The average accuracy of 30 discriminant results reached 82.74%, and the average optimization time was 0.45 s. The results demonstrate that the serum Raman spectroscopy technique combined with the AFUD-SVM discriminant model has great potential for the detection of thyroid dysfunction. This technique could be used to develop a portable, rapid, and low-cost device for detecting thyroid function to meet the needs of individuals and communities.
关键词： Raman spectroscopy,support vector machine (SVM),optical diagnosis,thyroid dysfunction,parameter optimization
更新于2025-09-23 15:21:01
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[IEEE 2018 2nd International Conference on Biomedical Engineering (IBIOMED) - Bali, Indonesia (2018.7.24-2018.7.26)] 2018 2nd International Conference on Biomedical Engineering (IBIOMED) - Early Detection of Tuberculosis using Chest X-Ray (CXR) with Computer-Aided Diagnosis
摘要： In this paper, a Computer-aided Diagnosis (CADx) system based on image processing is proposed to assist doctors and radiologists in interpreting Chest X-rays (CXR) for early detection of lung Tuberculosis (TB). CXR can indicate lung abnormalities including TB. However, the interpretations of CXR might vary from one individual to another. It is important to accurately and quickly detect TB because early treatment will prevent more infections and fatal effects from happening. The steps that were performed by the proposed system consisted of preprocessing, segmentation, feature extraction, and classification. In the preprocessing stage homomorphic filter, histogram equalization, median filter, and Contrast-Limited Adaptive Histogram Equalization (CLAHE) were applied to increase image quality. Segmentation was done by using Active Contour Model. Feature extraction was performed by analyzing the image’s first order statistical features. The last stage, classification, was based on the mean values. The results indicated that the system can increase specificity while maintaining sensitivity and accuracy of TB diagnosis. In conclusion, there is a high chance that CADx can assist doctors and radiologists for a more accurate and quick interpretation of CXR in early detection of TB.
关键词： Chest X-ray (CXR),Computer-aided Diagnosis (CADx),Early detection of tuberculosis
更新于2025-09-23 15:21:01
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DaBlaCa-11: Photodynamic diagnosis in flexible cystoscopy - initial findings in a randomized controlled trial
摘要： Patients with non-muscle invasive bladder cancer (NMIBC) face the risk of having several transurethral resections of the bladder (TURBT) performed because of the high recurrence rate of the disease. Photodynamic diagnosis (PDD) is recommended in primary TURBTs because of a higher detection rate than white light (WL) cystoscopy. In the surveillance program, however, WL flexible cystoscopy is still the standard approach. The aim of this randomized controlled trial is to examine the potential benefits from a PDD guided flexible cystoscopy in the outpatient clinic in patients with previous NMIBC. From February 2016 to September 2017, 605 patients were enrolled from three urological department in Denmark. All patients were scheduled for a routine surveillance cystoscopy following a TURBT because of Ta bladder cancer (low or high grade) 4 months earlier. Patients were randomized 1:1 to either an intervention group where Hexaminolevulinate (Hexvix?Photocure, NO) was instilled in the bladder one hour before the cystoscopy with PDD video cystoscope (PDD 11272 VPI, D-Light C-Light Source; Karl Storz), or a control group where cystoscopy was performed with WL flexible cystoscope. In both patient groups, detection of multiple and large recurrences estimated > 1 cm were scheduled for a TURBT in general anesthesia whereas solitary or small multiple recurrences, as well as suspect mucosa, were biopsied or fulgurated directly in the flexible procedure. A total of 304 patients were allocated to the intervention group (flexible PDD) and 301 to the control group (flexible WL). Approximately half of all patients in both groups were recurrence free (control group, n= 150 and intervention group, n=157). The number of patients undergoing biopsy or fulguration because of suspect mucosa were higher in the intervention group compared to the control group (n=66 vs. n=36, p<0.05). Significantly more patients in the intervention group were treated in the outpatient clinic (n=95) compared to the control group (n=76) (n=95 vs n=76, p <0.05), whereas fewer patients were scheduled for a TURBT in the intervention group (n=52) than in the control group (n=75) (n=52 vs n=75, p<0.05). These initial results indicate that PDD guided flexible cystoscopy can reduce the need of TURBT when biopsy and fulguration of small tumors is possible in the outpatient clinic. Further follow-up data on recurrences in patients in the study will be needed to estimate the clinical impact on this regarding reduction of recurrence risk and repeated procedures.
关键词： randomized controlled trial,flexible cystoscopy,Photodynamic diagnosis,non-muscle invasive bladder cancer
更新于2025-09-23 15:19:57
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Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry to Detect Diagnostic Glycopeptide Markers of Congenital Disorders of Glycosylation
摘要： Congenital disorders of glycosylation (CDG), an increasingly recognized group of diseases affecting glycosylation, comprise the largest known subgroup involving approximately 100 responsible genes related to N-glycosylation. This subgroup presents as various molecular abnormalities, of either the CDG-I or the CDG-II type, attributable to lack of glycans or abnormal glycoform profiles, respectively. The most effective approach to identifying N-glycosylation disorders is mass spectrometry (MS) using either released glycans, intact glycoproteins or proteolytic peptides as the analyte. Among these, MS of tryptic peptides of transferrin reliably identifies the signature peptides characteristic of CDG-I and II. In the present study, matrix-assisted laser desorption/ionization (MALDI) MS was applied to various N-glycosylation disorders including ALG1-CDG, B4GALT1-CDG, SLC35A2-CDG, ATP6V0A2-CDG, TRAPPC11-CDG and MAN1B1-CDG. This method does not require prior enrichment of glycopeptides or chromatographic separation, and thus serves as a practical alternative to liquid chromatography-electrospray ionization MS. The signature peptides are biomarkers of CDG.
关键词： diagnosis,congenital disorder of glycosylation,glycopeptide,screening
更新于2025-09-23 15:19:57
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Minimum material quality threshold for intermediate band solar cells using a multi-band device simulator with fully coupled optics
摘要： One of the common ways to perform data-driven fault diagnosis is to employ statistical models, which can classify the data into nominal (healthy) and a fault class or distinguish among different fault classes. The former is termed fault (anomaly) detection, and the latter is termed fault isolation (classi?cation, diagnosis). Traditionally, statistical classi?ers are trained using data from faulty and nominal behaviors in a batch mode. However, it is dif?cult to anticipate, a priori, all the possible ways in which failures can occur, especially when a new vehicle model is introduced. Therefore, it is imperative that diagnostic algorithms adapt to new cases on an ongoing basis. In this paper, a uni?ed methodology to incrementally learn new information from evolving databases is presented. The performance of adaptive (or incremental learning) classi?cation techniques is discussed when: 1) the new data has the same fault classes and same features and 2) the new data has new fault classes, but with the same set of observed features. The proposed methodology is demonstrated on data sets derived from an automotive electronic throttle control subsystem.
关键词： fault diagnosis,automotive systems,incremental classi?ers,Adaptive learning,ensemble systems
更新于2025-09-23 15:19:57
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Analyzing the Dynamics of the Laser Beam Cutting Process
摘要： Instabilities of the melt flow dynamics at the laser cutting front lead to quality losses, due to the formation of striations at the resulting cut flank. The application of high-speed video diagnosis has turned out to be very instructive for a well-founded process analysis. In this way, it was found out for the first time that the melt film dynamics at the cutting front reveal characteristic frequencies that are nearly independent of process parameters. Interestingly, their local appearance correlates with the area of lowest roughness on the resulting cut flanks. This observation suggests the amplification of the characteristic frequencies in order to obtain a reduced roughness over the complete cut depth. Comprehensible rules for optimized laser beam and gas flow parameters can be determined based on the physical understanding of the origin of the characteristic frequencies.
关键词： high-speed video diagnosis,characteristic frequencies,melt film dynamics,Laser cutting,surface roughness
更新于2025-09-23 15:19:57