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Using prerecorded hemodynamic response functions in detecting prefrontal pain response: a functional near-infrared spectroscopy study
摘要： Currently, there is no method for providing a nonverbal objective assessment of pain. Recent work using functional near-infrared spectroscopy (fNIRS) has revealed its potential for objective measures. We conducted two fNIRS scans separated by 30 min and measured the hemodynamic response to the electrical noxious and innocuous stimuli over the anterior prefrontal cortex (aPFC) in 14 subjects. Based on the estimated hemodynamic response functions (HRFs), we first evaluated the test–retest reliability of using fNIRS in measuring the pain response over the aPFC. We then proposed a general linear model (GLM)-based detection model that employs the subject-specific HRFs from the first scan to detect the pain response in the second scan. Our results indicate that fNIRS has a reasonable reliability in detecting the hemodynamic changes associated with noxious events, especially in the medial portion of the aPFC. Compared with a standard HRF with a fixed shape, including the subject-specific HRFs in the GLM allows for a significant improvement in the detection sensitivity of aPFC pain response. This study supports the potential application of individualized analysis in using fNIRS and provides a robust model to perform objective determination of pain perception.
关键词： test–retest reliability,detection sensitivity,hemodynamic response function,anterior prefrontal cortex,pain,near-infrared spectroscopy
更新于2025-09-10 09:29:36
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Near-infrared spectroscopy monitoring during out-of-hospital cardiac arrest: can the initial cerebral tissue oxygenation index predict ROSC?
摘要： study objectives Near-infrared spectroscopy is a modality that can monitor tissue oxygenation index (TOI) and has potential to evaluate return of spontaneous circulation (ROSC) during cardiopulmonary resuscitation (CPR). This study’s objectives were to evaluate whether TOI could be associated with ROSC and used to help guide the decision to either terminate CPR or proceed to extracorporeal CPR (ECPR). Methods In this observational study, we assessed the patients with out-of-hospital cardiac arrest with non-traumatic cause receiving CPR on arrival at our ED between 2013 and 2016. TOI monitoring was discontinued either on CPR termination after ROSC was reached or on patient death. Patients were classified into two groups: ROSC and non-ROSC group. results Out of 141 patients, 24 were excluded and the remaining 117 were classified as follows: ROSC group (n=44) and non-ROSC group (n=73). ROSC group was significantly younger and more likely to have their event witnessed and bystander CPR. ROSC group showed a higher initial TOI than non-ROSC group (60.5%±17.0% vs 37.9%±13.7%: p<0.01). Area under the curve analysis was more accurate with the initial TOI than without it for predicting ROSC (0.88, 95% CI 0.82 to 0.95 vs 0.79, 95% CI 0.70 to 0.87: p<0.01). TOI cut-off value ≥59% appeared to favour survival to hospital discharge whereas TOI ≤24% was associated with non-ROSC. Conclusions This study demonstrated an association between higher initial TOI and ROSC. Initial TOI could increase the accuracy of ROSC prognosis and may be a clinical factor in the decision to terminate CPR and select patients who are to proceed to ECPR.
关键词： tissue oxygenation index,Near-infrared spectroscopy,extracorporeal CPR,cardiopulmonary resuscitation,return of spontaneous circulation
更新于2025-09-10 09:29:36
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Non-invasive dynamic assessment of conjunctival melanomas using photoacoustic imaging
摘要： This study describes non-invasive photoacoustic imaging to detect and monitor the growth of conjunctival melanomas in vivo. Conjunctival melanomas were induced by injection of melanotic B16F10 cells into the subconjunctival space in syngeneic albino C57BL/6 mice. Non-invasive in vivo photoacoustic tomography was performed before, and after tumor induction up to 2 weeks. Spectral unmixing was performed to determine the location and to assess the distribution of melanin. The melanin photoacoustic signal intensity was quantified from the tumor-bearing and control eyes at all timepoints. For postmortem validation, total tumor and melanotic tumor volumes were measured using H&E stained tumor sections and were compared to in vivo photoacoustic imaging measurements. Photoacoustic imaging non-invasively detected eyes bearing conjunctival tumors of varying sizes. The melanin signal was detected as early as immediately following injection of melanotic tumor cells. Changes in tumor size over time were assessed with changes in the volume and intensity of the melanin signal. Four growing tumors and one regressing tumor were observed. Three tumors without significant change in signal intensity over time were observed, showing variable growth. Photoacoustic melanin signal on the last day of in vivo imaging correlated with postmortem total tumor volume (R2 = 0.81) and melanotic tumor volume (R2 = 0.80). The results of our study show that the growth of conjunctival melanomas can be quantified in a non-invasive manner using in vivo photoacoustic tomography. The photoacoustic melanin signal intensity correlated with total and melanotic tumor volume. This novel in vivo imaging platform may aid in assessing new treatment modalities to treat ocular tumors.
关键词： near-infrared,mouse,melanin detection,photoacoustic imaging,oncology,in vivo,ocular melanoma
更新于2025-09-10 09:29:36
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Quantifying several adulterants of notoginseng powder by near-infrared spectroscopy and multivariate calibration
摘要： The authentication of traditional Chinese medicine (TCM) is critically important for public-health and economic terms. Notoginseng, a classical TCM of high economic and medical value, could be easily adulterated with sophora flavescens powder (SFP), corn flour (CF) or other analogues of low-grade (ALG) because of their similar tastes, appearances and much lower cost. The main objective of this study was to evaluate the feasibility of applying of near-infrared (NIR) spectroscopy and multivariate calibration for identifying and quantifying several common adulterants in notoginseng powder. Two datasets were prepared for experiment. The competitive adaptive reweighted sampling (CARS) was used to select informative variables. Two different schemes were used for sample set partition. Model population analysis (MPA) was made. The results showed that, the constructed partial least squares (PLS) model using a reduced set of variables from CARS can provide superior performance to the full-spectrum PLS model. Also, the sample set partition is very of great importance. It seems that the combination of NIR spectroscopy, CARS and PLS is feasible to quantify common adulterants in notoginseng powder.
关键词： calibration,Notoginseng,adulteration,near-infrared
更新于2025-09-10 09:29:36
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Synthesis and bioluminescence of electronically modified and rotationally restricted colour-shifting infraluciferin analogues
摘要： Synthetic nIR emitting luciferins can enable clearer bioluminescent imaging in blood and tissue. A limiting factor for all synthetic luciferins is their reduced light output with respect to D-luciferin. In this work we explore a design feature of whether rigidification of an exceptionally red synthetic luciferin, infraluciferin, can increase light output through a reduction in the degrees of freedom of the molecule. A rigid analogue pyridobenzimidazole infraluciferin was prepared and its bioluminescence properties compared with its non-rigid counterpart benzimidazole infraluciferin, luciferin, infraluciferin and benzimidazole luciferin. The results support the concept that synthetic rigidification of p -extended luciferins can increase bioluminescence activity while maintaining nIR bioluminescence.
关键词： bioluminescence,near infrared,infraluciferin,synthesis,colour shifting
更新于2025-09-10 09:29:36
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In vivo theranostics with near-infrared-emitting carbon dots—highly efficient photothermal therapy based on passive targeting after intravenous administration
摘要： Carbon dots that exhibit near-infrared fluorescence (NIR CDs) are considered emerging nanomaterials for advanced biomedical applications with low toxicity and superior photostability and targeting compared to currently used photoluminescence agents. Despite progress in the synthesis of NIR CDs, there remains a key obstacle to using them as an in vivo theranostic agent. This work demonstrates that the newly developed sulfur and nitrogen codoped NIR CDs are highly efficient in photothermal therapy (PTT) in mouse models (conversion efficiency of 59%) and can be readily visualized by photoluminescence and photoacoustic imaging. The real theranostic potential of NIR CDs is enhanced by their unique biodistribution and targeting. Contrary to all other nanomaterials that have been tested in biomedicine, they are excreted through the body’s renal filtration system. Moreover, after intravenous injection, NIR CDs are accumulated in tumor tissue via passive targeting, without any active species such as antibodies. Due to their accumulation in tumor tissue without the need for intratumor injection, high photothermal conversion, excellent optical and photoacoustic imaging performance, and renal excretion, the developed CDs are suitable for transfer to clinical biomedical practice.
关键词： Theranostics,Photoacoustic imaging,Carbon dots,Near-infrared fluorescence,Photothermal therapy
更新于2025-09-10 09:29:36
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Stable Thiele’s Hydrocarbon Derivatives Exhibiting Near-Infrared Absorption/Emission and Two-Step Electrochromism
摘要： We report synthesis and characterization of near-infrared (NIR)-absorbing/emitting Thiele’s hydrocarbon derivatives, in which four aryl groups are bridged to a quinodimethane skeleton. The quinoid structure of the bridged-tetra-aryl-p-quinodimethanes (BTAQs) was confirmed by spectroscopic, X-ray crystallographic, and computational methods. Although quinodimethane derivatives with a small HOMO–LUMO energy gap often exhibit biradical character, BTAQs showed no biradical character. Instead, they exhibited two-step near-infrared electrochromism. The donor/acceptor properties of the aryl groups were found to play a key role in the unique properties of BTAQs.
关键词： Thiele’s hydrocarbon,emission,absorption,electrochromism,near-infrared
更新于2025-09-10 09:29:36
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Straight for the sun
摘要： Certain types of star evolve into supernovae (pictured), whose light we can observe with telescopes. Supernovae are classified according to the presence or absence of elements in their optical spectra. But the supernova SN 2017ens shows a spectrum in the ultraviolet and near-infrared range, which fits none of the known categories — so astrophysicists are curious to understand the formation and evolution of this particular supernova. Now, Ting-Wan Chen and colleagues have reported the observation of SN 2017ens over more than 260 days. The supernova was initially a hot blue object without features. Shortly after the spectral peak was observed, narrow emission lines started to appear in the spectrum, and over time, broader features developed. After 160 days, the spectrum evolved dramatically: although it remained within the blue, the spectrum was dominated by wide emission lines. Accompanying measurements show that SN 2017ens could have been a pulsational pair instability supernova, in which a fraction of the star’s mass is disrupted followed by a core collapse or hypernova.
关键词： supernovae,ultraviolet,SN 2017ens,near-infrared,pulsational pair instability supernova
更新于2025-09-10 09:29:36
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[IEEE 2018 37th Chinese Control Conference (CCC) - Wuhan (2018.7.25-2018.7.27)] 2018 37th Chinese Control Conference (CCC) - Near-Infrared Spectrum of Coal Origin Identification Based on SVM Algorithm
摘要： Near infrared spectroscopy is introduced to analyze 243 coal samples of different origins of Australia, Canada, China, Indonesia and Russia, combined with the supportive vector machines (SVM) analysis method. With the pre-processed data from the Principal component analysis (PCA), six supportive vector machines with different kernel functions are employed to discriminate origins of coal samples, namely Linear SVM, Quadratic SVM, Cubic SVM, Fine Gaussian SVM, Medium Gaussian SVM and Coarse Gaussian SVM. Through comparison, Linear SVM has the best performance in prediction accuracy rate while better results are obtained using Medium Gaussian SVM taking accuracy rate and training time into account. It turns out that NIR spectroscopy combined with Medium Gaussian SVM can be used as a good non-destructive method to predict origins of coal, with an accuracy rate of 98.8%, which strengthens the supervision of coal quality.
关键词： Principal component analysis,K- fold cross validation,Supportive vector machines,Near infrared spectroscopy
更新于2025-09-10 09:29:36
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Implementing a method based on near infrared spectroscopy for the “in-situ” determination of ammonia/water composition in an absorber test bench
摘要： This study presents the first results of composition measurement in an ammonia/water mixture determined at real time using near-infrared (NIR) spectroscopy in an absorber test bench. Two cells were designed and constructed; a static cell for calibrating and a dynamic cell for measuring in the absorber test bench. The ammonia absorption band was not significantly affected by the solution flow rate and neither by small variations in the temperature and pressure. A linear regression model between the absorbance value at 1033 nm and the ammonia concentration was established. This model was used to estimate the concentration in an ammonia/water absorber test bench. The methodology was validated by density measurements of the samples. The value of the mean deviation was 0.0024.
关键词： ammonia/water composition,near-infrared spectroscopy,absorber test bench,real-time measurement
更新于2025-09-10 09:29:36