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- 摘要
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- 实验方案
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Dynamic spectrum nonlinear modeling of VIS & NIR band based on RBF neural network for noninvasive blood component analysis to consider the effects of scattering
摘要： Dynamic spectrum (DS) is expected to achieve non-invasive analysis of blood components by extracting the absorbance of arterial blood at multiple wavelengths. However, the nonlinearity caused by scattering of blood components is still a factor that limits the detection accuracy. According to the idea of “overlay modeling” in the “M + N” theory, theoretically, the consideration of nonlinear factor in modeling analysis can further improve the prediction accuracy of calibration model. But there is currently no recognized formula to describe this nonlinear relationship. In this paper, the ability of RBF neural network to approximate arbitrary nonlinear functions with arbitrary precision is used to approximate the nonlinear relationship between the spectrum and the component concentration from the perspective of ?tting. The calibration sets and prediction sets were randomly selected from the VIS & NIR band DS data of 231 volunteers, and 10 groups of modeling experiments were carried out. The results showed that compared with the conventional partial least squares (PLS) modeling method, the modeling indicators (correlation coe?cient (R) and root mean square error(RMSE)) of prediction set using radial basis function (RBF) neural network modeling have been signi?cantly improved. The modeling experiments suggest that the nonlinearity caused by scattering should not be ignored in DS non-invasive blood component analysis. By ?tting the nonlinear relationship, RBF neural network can better re?ect the actual mapping relationship between the spectrum and the component concentration, because it can not only consider the general part (Linear factor) in DS, but also the details (Nonlinear factor), which can e?ectively improve the accuracy of the non-invasive blood component analysis based on DS.
关键词： Scattering,Nonlinearity,RBF neural network,Dynamic spectrum (DS),Non-invasive detection
更新于2025-09-23 15:23:52
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New Assay Method Based on Raman Spectroscopy for Enzymes Reacting with Gaseous Substrates
摘要： Enzyme activity is typically assayed by quantitatively measuring the initial and final concentrations of the substrates and/or products over a defined time period. For enzymatic reactions involving gaseous substrates, the substrate concentrations can be estimated either directly by gas chromatography or mass spectrometry, or indirectly by absorption spectroscopy, if the catalytic reactions involve electron transfer with electron mediators that exhibit redox-dependent spectral changes. We have developed a new assay system for measuring the time course of enzymatic reactions involving gaseous substrates based on Raman spectroscopy. This system permits continuous monitoring of the gas composition in the reaction cuvette in a non-invasive manner over a prolonged time period. We have applied this system to the kinetic study of the [NiFe] hydrogenase from Desulfovibrio vulgaris Miyazaki F. This enzyme physiologically catalyzes the reversible oxidation of H2 and also possesses the non-physiological functions of H/D exchange and nuclear spin isomer conversion reactions. The proposed system has the additional advantage of enabling us to measure all of the hydrogenase-mediated reactions simultaneously. Using the proposed system, we confirmed that H2 (the fully exchanged product) is concomitantly produced alongside HD by the H/D exchange reaction in the D2/H2O system. Based on a kinetic model, the ratio of the rate constants of the H/D exchange reaction (k) at the active site and product release rate (kout) was estimated to be 1.9±0.2. The proposed assay method based on Raman spectroscopy can be applied to the investigation of other enzymes involving gaseous substrates.
关键词： kinetic experiment,H/D exchange reaction,quantitative analysis of gaseous substrates,Raman spectroscopy,non-invasive measurement,[NiFe] hydrogenase
更新于2025-09-23 15:23:52
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A Novel Whole Spectrum-based Non-invasive Screening Device for Neonatal Hyperbilirubinemia
摘要： Objective: Careful screening of bilirubin level in newborns is mandatory as per American Academy of Pediatrics (2004), to reduce incidents of kernicterus and acute bilirubin encephalopathy. Although invasive capillary collection of blood and subsequent biochemical test is considered a gold standard for jaundice detection in neonates, transcutaneous bilirubin (TcB) measurement using various non-invasive instruments is also used sporadically across the globe. The major aim of this study was to develop a non-invasive spectrometry-based technique for measurement of neonatal bilirubin level as an alternative of total serum bilirubin (TSB) test without limitations of other available bilirubinometers. Methods: The instrument comprised of a light source and a spectroscopic detector. A light beam from source incident on the neonatal nail plate through optical fibers. The retro reflected light is acquired using the detector. An indigenously developed software used to acquire and analyze the optical signal and to calculate the bilirubin value. The instrument was calibrated and validated in reference to TSB on 1033 subjects. Major results: The result (r=0.95 and P<0.001), indicates a strong correlation between the bilirubin value obtained from our method and TSB. Time variant analysis of the subjects undergoing phototherapy provided a good correlation (r = 0.98). The repeatability test, result shows the mean coefficient of variation less than 5.0%. Conclusions: The indigenously developed non-invasive technique, successfully detects the bilirubin under various physiological conditions with high accuracy and precision.
关键词： non-invasive optical method,LabVIEW,diffuse reflection,Neonatal jaundice,whole spectrum-based diagnosis
更新于2025-09-23 15:22:29
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[IEEE 2018 IEEE Biomedical Circuits and Systems Conference (BioCAS) - Cleveland, OH, USA (2018.10.17-2018.10.19)] 2018 IEEE Biomedical Circuits and Systems Conference (BioCAS) - Battery-Free. Sticker-Like, Device for Health Monitoring, Operated by Optical Power Transfer
摘要： This work presents the concept of a battery-free, sticker-like, device for a non-invasive health-monitoring sensor. The device consists of two functional blocks: an optical power-transfer block and an amperometric measurement block. The former accumulates power from a series-connected photovoltaic cell in a capacitor and intermittently supplies the power to the amperometric measurement circuit. This circuit is driven by powering pulses and displays the amperometric current as the durations of the light pulses from a light-emitting diode. The function of the circuit was successfully demonstrated through simulations, in which the equivalent circuit of an electrochemical glucose sensor was used as an example. The simulation results showed that the proposed device would work as expected for a variety of glucose concentrations at an oxidation voltage of 0.8 V.
关键词： optical power transfer,personalized medicine,battery-free,non-invasive,glucose monitoring,electrochemical
更新于2025-09-23 15:22:29
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Overcoming Individual Discrepancies, a Learning Model for Non-Invasive Blood Glucose Measurement
摘要： Non-invasive Glucose Measurement (NGM) technology makes great sense for the blood glucose management of patients with hyperglycemia or hypoglycemia. Individual Discrepancies (IDs), e.g., skin thickness and color, not only block the development of NGM, but also become the reason why NGM cannot be widely used. To solve this problem, our solution is designing an individual customized NGM model that can measure these discrepancies through multi-wavelength and tune parameters for glucose estimating. In this paper, an NGM prototype is designed, and a learning model for glucose estimating with automatically parameters tuning based on Independent Component Analysis (ICA) and Random Forest (RF) is presented. The clinic trial proves that the correlation coefficient between estimation and reference Blood Glucose Concentration (BGC) can reach 0.5 after merely 10 times of learning, and rise to 0.8 after about 60 times of learning.
关键词： Independent Component Analysis (ICA),random forest,non-invasive,blood glucose,diabetes
更新于2025-09-23 15:22:29
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1D ballistic transport channel probed by invasive and non-invasive contacts
摘要： Epitaxially grown sidewall graphene nanoribbons show a robust quantum conductance of e2/h. By means of in-situ transport measurements with a nanoprobe system, we realized invasive and non-invasive 4-point-probe configurations. The invasiveness correlates with the contact resistance of the voltage probes. In particular, we achieved now non-invasive voltage probes revealing an almost zero resistance in a collinear 4 point-probe measurement. This proofs the ballistic nature of our epitaxially grown sidewall nanoribbons on SiC(0001) mesa structures.
关键词： quantum conductance,graphene nanoribbons,ballistic transport,non-invasive contacts,invasive contacts
更新于2025-09-23 15:21:21
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Perspective: Prospects of non-invasive sensing of the human brain with diffuse optical imaging
摘要： Since the initial demonstration of near-infrared spectroscopy (NIRS) for noninvasive measurements of brain perfusion and metabolism in the 1970s, and its application to functional brain studies (fNIRS) in the 1990s, the field of noninvasive optical studies of the brain has been continuously growing. Technological developments, data analysis advances, and novel areas of application keep advancing the field. In this article, we provide a view of the state of the field of cerebral NIRS, starting with a brief historical introduction and a description of the information content of the NIRS signal. We argue that NIRS and fNIRS studies should always report data of both oxy- and deoxyhemoglobin concentrations in brain tissue, as they complement each other to provide more complete functional and physiological information, and may help identify different types of confounds. One significant challenge is the assessment of absolute tissue properties, be them optical or physiological, so that relative measurements account for the vast majority of NIRS and fNIRS applications. However, even relative measurements of hemodynamics or metabolic changes face the major problem of a potential contamination from extracerebral tissue layers. Accounting for extracerebral contributions to fNIRS signals is one of the most critical barriers in the field. We present some of the approaches that were proposed to tackle this challenge in the study of cerebral hemodynamics and functional connectivity. Finally, we critically compare fNIRS and functional magnetic resonance imaging by relating their measurements in terms of signal and noise, and by commenting on their complementarity.
关键词： hemodynamics,functional connectivity,functional magnetic resonance imaging,human brain,near-infrared spectroscopy,diffuse optical imaging,non-invasive sensing,functional near-infrared spectroscopy
更新于2025-09-23 15:21:21
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Highly Sensitive Room-Temperature Sensor Based on Nanostructured K2W7O22 for Application in the Non-Invasive Diagnosis of Diabetes
摘要： Diabetes is one of the most rapidly-growing chronic diseases in the world. Acetone, a volatile organic compound in exhaled breath, shows a positive correlation with blood glucose and has proven to be a biomarker for type-1 diabetes. Measuring the level of acetone in exhaled breath can provide a non-invasive, low risk of infection, low cost, and convenient way to monitor the health condition of diabetics. There has been continuous demand for the improvement of this non-invasive, sensitive sensor system to provide a fast and real-time electronic readout of blood glucose levels. A novel nanostructured K2W7O22 has been recently used to test acetone with concentration from 0 parts-per-million (ppm) to 50 ppm at room temperature. The results revealed that a K2W7O22 sensor shows a sensitive response to acetone, but the detection limit is not ideal due to the limitations of the detection system of the device. In this paper, we report a K2W7O22 sensor with an improved sensitivity and detection limit by using an optimized circuit to minimize the electronic noise and increase the signal to noise ratio for the purpose of weak signal detection while the concentration of acetone is very low.
关键词： non-invasive,biomarker,ferroelectric property,blood glucose,volatile organic compound,acetone,nanostructured K2W7O22,diabetes
更新于2025-09-23 15:21:21
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Advances in Mid-Infrared Spectroscopy-Based Sensing Techniques for Exhaled Breath Diagnostics
摘要： Human exhaled breath consists of more than 3000 volatile organic compounds, many of which are relevant biomarkers for various diseases. Although gas chromatography has been the gold standard for volatile organic compound (VOC) detection in exhaled breath, recent developments in mid-infrared (MIR) laser spectroscopy have led to the promise of compact point-of-care (POC) optical instruments enabling even single breath diagnostics. In this review, we discuss the evolution of MIR sensing technologies with a special focus on photoacoustic spectroscopy, and its application in exhaled breath biomarker detection. While mid-infrared point-of-care instrumentation promises high sensitivity and inherent molecular selectivity, the lack of standardization of the various techniques has to be overcome for translating these techniques into more widespread real-time clinical use.
关键词： point-of-care (POC),infrared lasers,MIR,photoacoustic spectroscopy,biomarkers,exhaled breath analysis,non-invasive diagnostics,QCL,quantum cascade lasers,mid-infrared
更新于2025-09-23 15:21:01
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LLLT FOR FEMALE INFERTILITY: NO LONGER JUST A DREAM
摘要： The editorial discusses the application of Low Level Laser Therapy (LLLT) for female infertility, highlighting its potential as a non-invasive treatment method. It recounts the history of LLLT's incidental discovery in treating infertility during pain management sessions and its subsequent development through the Japan Society for Laser Reproduction (JaSLaR). The editorial also mentions the 10th Memorial Congress of JaSLaR and the 21st ISLSM meeting in Indore, India, emphasizing the growing recognition of LLLT in medical treatments.
关键词： female infertility,ISLSM,JaSLaR,LLLT,non-invasive treatment
更新于2025-09-23 15:21:01