This paper describes the design and performance of the tender energy spectroscopy beamline(BL16U1),a phase Ⅱ beamline,at the Shanghai Synchrotron Radiation Facility.The beamline,based on an in-vacuum undulator source...This paper describes the design and performance of the tender energy spectroscopy beamline(BL16U1),a phase Ⅱ beamline,at the Shanghai Synchrotron Radiation Facility.The beamline,based on an in-vacuum undulator source with 26 mm period,provides an operable energy range between 2.1 keV and 16 keV,covering the K-edges of P to Rb and L3-edges of Zr to Bi.The principal optical elements of the beamline are a toroidal mirror,a liquid nitrogen-cooled double-crystal monochromator,a high-harmonic-rejection mirror,and two pairs of Kirkpatrick–Baez(KB)mirrors.Three end-stations,including non-focusing,microprobe,and sub-microprobe types,are installed on the beamline.X-ray fluorescence(XRF)and X-ray absorption spectroscopy(XAS),including X-ray absorption near-edge structure(XANES)and extended X-ray absorption fine structure(EXAFS),are performed under vacuum or He atmosphere at the non-focusing end-station(with a beam spot size of∼670μm×710μm).Using two KB mirrors systems,micro-XRF(μXRF)mapping and micro-XANES(μXANES)studies can be performed with a spot size of approximately∼3.3μm×1.3μm at the microprobe end-station and with a smaller spot size of∼0.5μm×0.25μm at the sub-microprobe end-station.The non-focusing end-station was officially opened to users in January 2024.The microprobe and sub-microprobe end-stations will be opened to users in the near future.This paper presents the characteristics,short-term technical developments,and early experimental results of this new beamline.展开更多
A RadioFrequency Quadrupole(RFQ)cooler-buncher system was developed and implemented in a collinear laser spectroscopy setup.This system converts a continuous ion beam into short bunches while enhancing the beam qualit...A RadioFrequency Quadrupole(RFQ)cooler-buncher system was developed and implemented in a collinear laser spectroscopy setup.This system converts a continuous ion beam into short bunches while enhancing the beam quality and reducing the energy spread.The functionality of the RFQ cooler buncher was verified through offline tests with stable rubidium and indium beams delivered from a surface ion source and a laser ablation ion source,respectively.Bunched ion beams with a full width at half maximum of approximately 2μs in the time-of-flight spectrum were successfully achieved with a transmission efficiency exceeding 60%.The implementation of the RFQ cooler-buncher system also significantly improved the overall transmission efficiency of the collinear laser spectroscopy setup.展开更多
Background:Magnetic resonance spectroscopy(MRS)represents a significant advancement in the noninvasive assessment of brain metabolism.MRS can provide valuable metabolic information and facilitate more accurate diagnos...Background:Magnetic resonance spectroscopy(MRS)represents a significant advancement in the noninvasive assessment of brain metabolism.MRS can provide valuable metabolic information and facilitate more accurate diagnoses of intrauterine fetal brain development than was previously possible.To obtain information regarding normal intrauterine fetal brain metabolism and to establish gestational age-specific reference values for normal fetal brain metabolites for subsequent use in MRS,we conducted MRS scans of normal fetal brains during mid-to late-term pregnancies,along with related processing.Methods:In this prospective study,MRS scans were conducted on 109 fetuses,with a total of 54 normal fetal brains enrolled on the basis of specific inclusion and exclusion criteria.We analyzed metabolic ratios,including the sum of N-acetylaspartate(NAA)and total N-acetylaspartate(tNAA),total choline(tCho),inositol(Ins),and total creatine(tCr),in relation to gestational age.Results:Gestational age was significantly correlated with specific metabolic ratios(Ins/tCr:r=-0.75,p<0.0001;tCho/tCr:r=-0.50,p<0.0001),especially tNAA/tCho(tNAA/tCho:r=0.54,p<0.0001)and tNAA/Ins(r=0.56,p<0.0001),providing a baseline for fetal brain metabolic assessment.Linear regression analysis was used to calculate regression lines for fetal brain metabolite ratios.Slopes were tested at p of 0.05.Conclusions:The current findings confirmed a significant correlation between fetal brain metabolites and gestational age,supporting the feasibility of establishing standard values for these metabolites in fetal brain assessment.展开更多
In this paper,a novel four-prong quartz tuning fork(QTF)was designed with enlarged deformation area,large prong gap,and low resonant frequency to improve its performance in laser spectroscopy sensing.A theoretical sim...In this paper,a novel four-prong quartz tuning fork(QTF)was designed with enlarged deformation area,large prong gap,and low resonant frequency to improve its performance in laser spectroscopy sensing.A theoretical simulation model was established to optimize the design of the QTF structure.In the simulation of quartz-enhanced photoacoustic spectroscopy(QEPAS)technology,the maximum stress and the surface charge density of the four-prong QTF demonstrated increases of 11.1-fold and 15.9-fold,respectively,compared to that of the standard two-prong QTF.In the simulation of light-induced thermoelastic spectroscopy(LITES)technology,the surface temperature difference of the four-prong QTF was found to be 11.4 times greater than that of the standard QTF.Experimental results indicated that the C_(2)H_(2)-QEPAS system based on this innovative design improved the signal-to-noise-ratio(SNR)by 4.67 times compared with the standard QTF-based system,and the SNR could increase up to 147.72 times when the four-prong QTF was equipped with its optimal acoustic micro-resonator(AmR).When the average time of the system reached 370 s,the system achieved a MDL as low as 21 ppb.The four-prong QTF-based C_(2)H_(2)-LITES system exhibited a SNR improvement by a factor of 4.52,and a MDL of 96 ppb was obtained when the average time of the system reached 100 s.The theoretical and experimental results effectively demonstrated the superiority of the four-prong QTF in the field of laser spectroscopy sensing.展开更多
BACKGROUND Esophageal squamous cell carcinoma is a major histological subtype of esophageal cancer.Many molecular genetic changes are associated with its occurrence.Raman spectroscopy has become a new method for the e...BACKGROUND Esophageal squamous cell carcinoma is a major histological subtype of esophageal cancer.Many molecular genetic changes are associated with its occurrence.Raman spectroscopy has become a new method for the early diagnosis of tumors because it can reflect the structures of substances and their changes at the molecular level.AIM To detect alterations in Raman spectral information across different stages of esophageal neoplasia.METHODS Different grades of esophageal lesions were collected,and a total of 360 groups of Raman spectrum data were collected.A 1D-transformer network model was proposed to handle the task of classifying the spectral data of esophageal squamous cell carcinoma.In addition,a deep learning model was applied to visualize the Raman spectral data and interpret their molecular characteristics.RESULTS A comparison among Raman spectral data with different pathological grades and a visual analysis revealed that the Raman peaks with significant differences were concentrated mainly at 1095 cm^(-1)(DNA,symmetric PO,and stretching vibration),1132 cm^(-1)(cytochrome c),1171 cm^(-1)(acetoacetate),1216 cm^(-1)(amide III),and 1315 cm^(-1)(glycerol).A comparison among the training results of different models revealed that the 1Dtransformer network performed best.A 93.30%accuracy value,a 96.65%specificity value,a 93.30%sensitivity value,and a 93.17%F1 score were achieved.CONCLUSION Raman spectroscopy revealed significantly different waveforms for the different stages of esophageal neoplasia.The combination of Raman spectroscopy and deep learning methods could significantly improve the accuracy of classification.展开更多
Raman spectroscopy offers a great power to detect,analyze and identify molecules,and monitor their temporal dynamics and evolution when combined with single-molecule surface-enhanced Raman scattering(SM-SERS)substrate...Raman spectroscopy offers a great power to detect,analyze and identify molecules,and monitor their temporal dynamics and evolution when combined with single-molecule surface-enhanced Raman scattering(SM-SERS)substrates.Here we present a SM-SERS scheme that involves simultaneously giant chemical enhancement from WS22D materials,giant electromagnetic enhancement from plasmonic nanogap hot spot,and inhibition of molecular fluorescence influence under near-infrared laser illumination.Remarkably we find Coulomb attraction between analyte and gold nanoparticle can trigger spontaneous formation of molecule-hotspot pairing with high precision,stability and robustness.The scheme has enabled realization of universal,robust,fast,and large-scale uniform SM-SERS detection for three Raman molecules of rhodamine B,rhodamine 6G,and crystal violet with a very low detection limit of 10−16 M and at a very fast spectrum acquisition time of 50 ms.展开更多
All-solid-state lithium batteries(ASSLBs)are strongly considered as the next-generation energy storage devices for their high energy density and intrinsic safety.The solid-solid contact between lithium metal and solid...All-solid-state lithium batteries(ASSLBs)are strongly considered as the next-generation energy storage devices for their high energy density and intrinsic safety.The solid-solid contact between lithium metal and solid electrolyte plays a vital role in the performance of working ASSLBs,which is challenging to investigate quantitatively by experimental approach.This work proposed a quantitative model based on the finite element method for electrochemical impedance spectroscopy simulation of different solid-solid contact states in ASSLBs.With the assistance of an equivalent circuit model and distribution of relaxation times,it is discovered that as the number of voids and the sharpness of cracks increase,the contact resistance Rcgrows and ultimately dominates the battery impedance.Through accurate fitting,inverse proportional relations between contact resistance Rcand(1-porosity)as well as crack angle was disclosed.This contribution affords a fresh insight into clarifying solid-solid contact states in ASSLBs.展开更多
Atmospheric chemistry research and atmospheric measurement techniques have mutually promoted each other and developed rapidly in China in recent years.Cavity-based absorption spectroscopy,which uses a high-finesse cav...Atmospheric chemistry research and atmospheric measurement techniques have mutually promoted each other and developed rapidly in China in recent years.Cavity-based absorption spectroscopy,which uses a high-finesse cavity to achieve very long absorption path-length,thereby achieving ultra-high detection sensitivity,plays an extremely important role in atmospheric chemistry research.Based on the Beer–Lambert law,this technology has the unique advantages of being non-destructive,chemical-free,and highly selective.It does not require any sample preparation and can quantitatively analyze atmospheric trace gases in real time and in situ.In this paper,we review the following:(1)key technological advances in different cavity-based absorption spectroscopy techniques,including cavity ring-down spectroscopy,cavityenhanced absorption spectroscopy,cavity attenuated phase shift spectroscopy,and their extensions;and(2)applications of these techniques in the detection of atmospheric reactive species,such as total peroxy radical,formaldehyde,and reactive nitrogen(e.g.,NOx,HONO,peroxy nitrates,and alkyl nitrates).The review systematically introduces cavity-based absorption spectroscopy techniques and their applications in atmospheric chemistry,which will help promote further communication and cooperation in the fields of laser spectroscopy and atmospheric chemistry.展开更多
In this editorial,we comment on the recent article by Fei et al exploring the field of near-infrared spectroscopy(NIRS)research in schizophrenia from a bibliometrics perspective.In recent years,NIRS has shown unique a...In this editorial,we comment on the recent article by Fei et al exploring the field of near-infrared spectroscopy(NIRS)research in schizophrenia from a bibliometrics perspective.In recent years,NIRS has shown unique advantages in the auxiliary diagnosis of schizophrenia,and the introduction of bibliometrics has provided a macro perspective for research in this field.Despite the opportunities brought about by these technological developments,remaining challenges require multidi-sciplinary approach to devise a reliable and accurate diagnosis system for schizo-phrenia.Nonetheless,NIRS-assisted technology is expected to contribute to the division of methods for early intervention and treatment of schizophrenia.展开更多
Although there are numerous optical spectroscopy techniques and methods that have been used to extract the fundamental bandgap of a semiconductor,most of them belong to one of these three approaches:(1)the excitonic a...Although there are numerous optical spectroscopy techniques and methods that have been used to extract the fundamental bandgap of a semiconductor,most of them belong to one of these three approaches:(1)the excitonic absorption,(2)modulation spectroscopy,and(3)the most widely used Tauc-plot.The excitonic absorption is based on a many-particle theory,which is physically the most correct approach,but requires more stringent crystalline quality and appropriate sample preparation and experimental implementation.The Tauc-plot is based on a single-particle theo⁃ry that neglects the many-electron effects.Modulation spectroscopy analyzes the spectroscopy features in the derivative spectrum,typically,of the reflectance and transmission under an external perturbation.Empirically,the bandgap ener⁃gy derived from the three approaches follow the order of E_(ex)>E_(MS)>E_(TP),where three transition energies are from exci⁃tonic absorption,modulation spectroscopy,and Tauc-plot,respectively.In principle,defining E_(g) as the single-elec⁃tron bandgap,we expect E_(g)>E_(ex),thus,E_(g)>E_(TP).In the literature,E_(TP) is often interpreted as E_(g),which is conceptual⁃ly problematic.However,in many cases,because the excitonic peaks are not readily identifiable,the inconsistency be⁃tween E_(g) and E_(TP) becomes invisible.In this brief review,real world examples are used(1)to illustrate how excitonic absorption features depend sensitively on the sample and measurement conditions;(2)to demonstrate the differences between E_(ex),E_(MS),and E_(TP) when they can be extracted simultaneously for one sample;and(3)to show how the popular⁃ly adopted Tauc-plot could lead to misleading results.Finally,it is pointed out that if the excitonic absorption is not ob⁃servable,the modulation spectroscopy can often yield a more useful and reasonable bandgap than Tauc-plot.展开更多
In the near-infrared(NIR)spectroscopic data of complex sample systems,such as tobacco leaves,nonlinearity is fairly significant between the absorbance and concentration.This nonlinearity severely degrades the quantita...In the near-infrared(NIR)spectroscopic data of complex sample systems,such as tobacco leaves,nonlinearity is fairly significant between the absorbance and concentration.This nonlinearity severely degrades the quantitative results of traditional methods,such as partial least squares regression(PLS),which can be used to construct linear models.The problem was addressed in this study by using deep learning(DL).We employed three different DL models:a one-dimensional convolutional neural network(1D CNN),a deep neural network(DNN),and a stacked autoencoder with feedforward neural networks(SAE-FNNs).By carefully selecting and tuning the architectures and parameters of these models,we were able to find the most suitable model for dealing with such nonlinear relationships.Our experimental findings reveal that both the DNN and the SAE-FNN models excel in addressing the nonlinear issues of pectin concentration in tobacco,surpassing the performance of the classic linear model(PLS).Specifically,the DNN model stands out for its low average root mean squared error of prediction(RMSEP)value and small standard deviation(SD)of RMSEPs,leading to a tighter and more centered distribution of residuals in the prediction set.These DL models not only proficiently identify complex patterns within NIR data but also boast high prediction accuracy and fast implementation,demonstrating their effectiveness in analytical applications.展开更多
To address the issues of peak overlap caused by complex matrices in agricultural product terahertz(THz)spectral signals and the dynamic,nonlinear interference induced by environmental and system noise,this study explo...To address the issues of peak overlap caused by complex matrices in agricultural product terahertz(THz)spectral signals and the dynamic,nonlinear interference induced by environmental and system noise,this study explores the feasibility of adaptive-signal-decomposition-based denoising methods to improve THz spectral quality.THz time-domain spectroscopy(THz-TDS)combined with an attenuated total reflection(ATR)accessory was used to collect THz absorbance spectra from 48 peanut samples.Taking the quantitative prediction model of peanut moisture content based on THz-ATR as an example,wavelet transform(WT),empirical mode decomposition(EMD),local mean decomposition(LMD),and its improved methods-segmented local mean decomposition(SLMD)and piecewise mirror extension local mean decomposition(PME-LMD)-were employed for spectral denoising.The applicability of different denoising methods was evaluated using a support vector regression(SVR)model.Experimental results show that the peanut moisture content prediction model constructed after PME-LMD denoising achieved the best performance,with a root mean square error(RMSE),coefficient of determination(R^(2)),and mean absolute percentage error(MAPE)of 0.010,0.912,and 0.040,respectively.Compared with traditional methods,PME-LMD significantly improved spectral quality and model prediction performance.The PME-LMD denoising strategy proposed in this study effectively suppresses non-uniform noise interference in THz spectral signals,providing an efficient and accurate preprocessing method for THz spectral analysis of agricultural products.This research provides theoretical support and technical guidance for the application of THz technology for detecting agricultural product quality.展开更多
Infrared(IR)spectroscopy,a technique within the realm of molecular vibrational spectroscopy,furnishes distinctive chemical signatures pivotal for both structural analysis and compound identification.A notable challeng...Infrared(IR)spectroscopy,a technique within the realm of molecular vibrational spectroscopy,furnishes distinctive chemical signatures pivotal for both structural analysis and compound identification.A notable challenge emerges from the misalignment between the mid-IR light wavelength range and molecular dimensions,culminating in a constrained absorption cross-section and diminished vibrational absorption coefficients(Supplementary data).展开更多
This communication looks at the photo-oxidation of polythene and polypropylene plastic bottle tops that are placed on soil in a hot arid environment. The degree of oxidation of the plastic is monitored by FT-IR spectr...This communication looks at the photo-oxidation of polythene and polypropylene plastic bottle tops that are placed on soil in a hot arid environment. The degree of oxidation of the plastic is monitored by FT-IR spectroscopy. It is noted that while different bottle top types photo-oxidize at different rates, all show an appreciable level of oxidation after half a year of exposure to the environment. The oxidation leads to brittleness of the plastic, which leads to fissure formation in bottle tops of little thickness. This leads to fragmentation of the material upon impact, making plastic bottle tops an appreciable source of microplastics.展开更多
Antifungal resistance is the leading cause of antifungal treatment failure in invasive candidiasis.Metabolic rewiring could become a new insight to account for antifungal resistance as to find innovative clinical ther...Antifungal resistance is the leading cause of antifungal treatment failure in invasive candidiasis.Metabolic rewiring could become a new insight to account for antifungal resistance as to find innovative clinical therapies.Here,we show that dynamic surface-enhanced Raman spectroscopy is a promising tool to identify the metabolic differences between fluconazole(Diflucan)-resistant and fluconazole(Diflucan)-sensitive Candida albicans through the signatures of biochemical components and complemented with machine learning algorithms and two-dimensional correlation spectroscopy,an underlying resistance mechanism,that is,the change of purine metabolites induced the resistance of Candida albicans has been clarified yet never reported anywhere.We hope the integrated methodology introduced in this work could be beneficial for the interpretation of cellular regulation,propelling the development of targeted antifungal therapies and diagnostic tools for more efficient management of severe antifungal resistance.展开更多
Revealing the factors that affect the vibrational frequency of Stark probe at interface is a pre-requirement for evaluating the absolute interfacial electric field.Here using surface-enhanced infrared absorption(SEIRA...Revealing the factors that affect the vibrational frequency of Stark probe at interface is a pre-requirement for evaluating the absolute interfacial electric field.Here using surface-enhanced infrared absorption(SEIRA)spectroscopy,attenuated total reflection(ATR)spectroscopy and molecular dynamics(MD),we reveal the assembled C≡N at gold nanofilm exhibits a reduced Stark tuning rate(STR)referring to the vibrational frequency shift in response to electric field comparing with the bulk which was regulated by the electron transfer between S and Au.These findings lead to a deeper understanding of the vibrational Stark effect at the interface and provide guidance for improving the interface electric field theory.展开更多
BACKGROUND Many patients with coronavirus disease 2019(COVID-19)may experience emotional issues and cognitive impairment.However,it remains unclear whether the brain mediates the impact of COVID-19 on the emergence of...BACKGROUND Many patients with coronavirus disease 2019(COVID-19)may experience emotional issues and cognitive impairment.However,it remains unclear whether the brain mediates the impact of COVID-19 on the emergence of psychopathological symptoms.It remains unclear whether anxiety and depression are caused by stressors or viral infection.AIM To use functional near-infrared spectroscopy(fNIRS)to detect cortical hemodynamic changes in patients with COVID-19 and their relationship with mental symptoms(mainly depression and anxiety),to investigate whether COVID-19 causes these changes by affecting brain function.METHODS A total of 58 subjects,comprising 29 patients with first acute COVID-19 infection and 29 healthy controls without COVID-19 infection and without anxiety or depression were recruited.Then cortical activation during the performance of the verbal fluency test(VFT)and brain connectivity during the resting state(rs)were evaluated by 53-channel fNIRS.For the COVID-19-infected group,Patient Health Questionnaire-9(PHQ-9)and General Anxiety Disorder-7(GAD-7)were used to assess the emotional state before fNIRS measures.RESULTS For the rs,compared to the uninfected group,the infected group exhibited lower rs functional connectivity(FC)in the dorsolateral prefrontal cortex(DLPFC),which was correlated with both the PHQ score and GAD score.During the VFT,the infected group exhibited significantly lower cortical activation than the uninfected group in both Broca-left and Broca-right.Besides,the integral value in the DLPFC-L showed a significant negative correlation with the PHQ-9 score during the VFT in the infected group.CONCLUSION There were significant differences in the bilateral Broca area and DLPFC between the COVID-19-infected and uninfected groups,which may be the reason why COVID-19 infection impairs cognitive function and language function and leads to psychiatric symptoms.In addition,the rsFC in patients with COVID-19 was positively correlated with the severity of depression and anxiety,which may be related to the fact that the mental symptoms of patients with COVID-19 are characterized by depression and anxiety,rather than depression or anxiety alone.Our study provides evidence that the psychological and emotional issues caused by COVID-19 are not only due to external social factors but also involve more direct brain neural mechanisms and abnormal neural circuits,which also provide insights into the future treatment and prognosis of individuals with COVID-19.展开更多
Nano-scale chemical inhomogeneity in surface oxide films formed on a V-and N-containing martensite stainless steel and tempering heating induced changes are investigated by a combination of synchrotron-based hard X-ra...Nano-scale chemical inhomogeneity in surface oxide films formed on a V-and N-containing martensite stainless steel and tempering heating induced changes are investigated by a combination of synchrotron-based hard X-ray Photoelectron emission spectroscopy(HAXPES)and microscopy(HAXPEEM)as well as microscopic X-ray absorption spectroscopy(μ-XAS)techniques.The results reveal the inhomogeneity in the oxide films on the micron-sized Cr_(2)N-and VN-type particles,while the inhomogeneity on the martensite matrix phase exists due to localised formation of nano-sized tempering nitride particles at 600℃.The oxide film formed on Cr_(2)N-type particles is rich in Cr_(2)O_(3) compared with that on the martensite matrix and VN-type particles.With the increase of tempering temperature,Cr_(2)O_(3) formation is faster for the oxidation of Cr in the martensite matrix than the oxidation of Cr nitride-rich particles.展开更多
The infinite-layer nickelates,proposed as analogs to superconducting cuprates,provide a promising platform for exploring the mechanisms of unconventional superconductivity.However,the superconductivity has been exclus...The infinite-layer nickelates,proposed as analogs to superconducting cuprates,provide a promising platform for exploring the mechanisms of unconventional superconductivity.However,the superconductivity has been exclusively observed in thin films under atmospheric pressure,underscoring the critical role of the heterointerface.展开更多
Background:The brain,which constitutes merely 2%of total body weight,receives approximately 15%of cardiac output and consumes about 20%of the body's oxygen,rendering it highly susceptible to hypoxia.Short-term oxy...Background:The brain,which constitutes merely 2%of total body weight,receives approximately 15%of cardiac output and consumes about 20%of the body's oxygen,rendering it highly susceptible to hypoxia.Short-term oxygen deprivation can lead to irreversible damage.Near-infrared spectroscopy(NIRS),operating within the 650–1100 nm wavelength range,enables non-invasive,continuous monitoring of cerebral tissue oxygen saturation(rSO_(2)).It has been extensively utilised in intensive care units,neurosurgery,cardiovascular surgery,and perioperative anaesthesia management.Recent advancements in domestically produced devices have progressed rapidly;however,variations in wavelength,sensor design,and algorithms across different brands mean that measurement values are not interchangeable.The accuracy and sensitivity of these devices necessitate comprehensive validation.Objective:This study aimed to evaluate the measurement performance of the domestically produced cerebral tissue oxygen saturation monitor(MOC200),determine its consistency and clinical applicability compared to the imported device(INVOS5100C),and investigate physiological factors influencing baseline rSO_(2)values.Method:A total of 222 healthy subjects aged 15 to 90 years were enrolled from January to March 2025.rSO_(2)was measured using both the MOC200 and INVOS5100C devices.Device performance was assessed via correlation analysis,linear regression,Bland-Altman agreement analysis,and difference testing.Results:Measurement values from MOC200 and INVOS5100C demonstrated high consistency,with a correlation coefficient of 0.786.Bland-Altman analysis indicated greater agreement for left hemisphere measurements,while right hemisphere and mean values exhibited relatively lower consistency.Age,gender,and haemoglobin levels are the primary factors influencing baseline rSO_(2)values,with haemoglobin showing a positive correlation,whereas increasing age and female gender are associated with lower rSO_(2)levels.Conclusion:The domestically developed MOC200 cerebral tissue oxygen saturation monitor reliably reflects cerebral oxygenation in healthy individuals,exhibiting accuracy and stability comparable to the imported device and demonstrating good measurement consistency.Age,sex,and haemoglobin are key physiological factors influencing baseline rSO_(2)in this population.展开更多
基金supported by the National Key R&D Program of China(No.2021YFA1601003)the financial support of the SSRF PhaseⅡproject.
文摘This paper describes the design and performance of the tender energy spectroscopy beamline(BL16U1),a phase Ⅱ beamline,at the Shanghai Synchrotron Radiation Facility.The beamline,based on an in-vacuum undulator source with 26 mm period,provides an operable energy range between 2.1 keV and 16 keV,covering the K-edges of P to Rb and L3-edges of Zr to Bi.The principal optical elements of the beamline are a toroidal mirror,a liquid nitrogen-cooled double-crystal monochromator,a high-harmonic-rejection mirror,and two pairs of Kirkpatrick–Baez(KB)mirrors.Three end-stations,including non-focusing,microprobe,and sub-microprobe types,are installed on the beamline.X-ray fluorescence(XRF)and X-ray absorption spectroscopy(XAS),including X-ray absorption near-edge structure(XANES)and extended X-ray absorption fine structure(EXAFS),are performed under vacuum or He atmosphere at the non-focusing end-station(with a beam spot size of∼670μm×710μm).Using two KB mirrors systems,micro-XRF(μXRF)mapping and micro-XANES(μXANES)studies can be performed with a spot size of approximately∼3.3μm×1.3μm at the microprobe end-station and with a smaller spot size of∼0.5μm×0.25μm at the sub-microprobe end-station.The non-focusing end-station was officially opened to users in January 2024.The microprobe and sub-microprobe end-stations will be opened to users in the near future.This paper presents the characteristics,short-term technical developments,and early experimental results of this new beamline.
基金supported by the National Natural Science Foundation of China(Nos.12027809,12350007)National Key R&D Program of China(Nos.2022YFA1605100,2023YFA1606403,and 2023YFE0101600)+1 种基金New Cornerstone Science Foundation through the XPLORER PRIZEfunding from the European Research Council(ERC)under the European Union’s Horizon 2020 research and innovation program under grant agreement No.679038.
文摘A RadioFrequency Quadrupole(RFQ)cooler-buncher system was developed and implemented in a collinear laser spectroscopy setup.This system converts a continuous ion beam into short bunches while enhancing the beam quality and reducing the energy spread.The functionality of the RFQ cooler buncher was verified through offline tests with stable rubidium and indium beams delivered from a surface ion source and a laser ablation ion source,respectively.Bunched ion beams with a full width at half maximum of approximately 2μs in the time-of-flight spectrum were successfully achieved with a transmission efficiency exceeding 60%.The implementation of the RFQ cooler-buncher system also significantly improved the overall transmission efficiency of the collinear laser spectroscopy setup.
基金supported by China Society for Maternal and Child Health Research(Gant/Award Number:2023CAMCHS003A17).
文摘Background:Magnetic resonance spectroscopy(MRS)represents a significant advancement in the noninvasive assessment of brain metabolism.MRS can provide valuable metabolic information and facilitate more accurate diagnoses of intrauterine fetal brain development than was previously possible.To obtain information regarding normal intrauterine fetal brain metabolism and to establish gestational age-specific reference values for normal fetal brain metabolites for subsequent use in MRS,we conducted MRS scans of normal fetal brains during mid-to late-term pregnancies,along with related processing.Methods:In this prospective study,MRS scans were conducted on 109 fetuses,with a total of 54 normal fetal brains enrolled on the basis of specific inclusion and exclusion criteria.We analyzed metabolic ratios,including the sum of N-acetylaspartate(NAA)and total N-acetylaspartate(tNAA),total choline(tCho),inositol(Ins),and total creatine(tCr),in relation to gestational age.Results:Gestational age was significantly correlated with specific metabolic ratios(Ins/tCr:r=-0.75,p<0.0001;tCho/tCr:r=-0.50,p<0.0001),especially tNAA/tCho(tNAA/tCho:r=0.54,p<0.0001)and tNAA/Ins(r=0.56,p<0.0001),providing a baseline for fetal brain metabolic assessment.Linear regression analysis was used to calculate regression lines for fetal brain metabolite ratios.Slopes were tested at p of 0.05.Conclusions:The current findings confirmed a significant correlation between fetal brain metabolites and gestational age,supporting the feasibility of establishing standard values for these metabolites in fetal brain assessment.
基金supports from the National Natural Science Foundation of China(Grant Nos.62335006,62022032,62275065,and 62405078)Key Laboratory of Opto-Electronic Information Acquisition and Manipulation(Anhui University),Ministry of Education(Grant No.OEIAM202202)+2 种基金Fundamental Research Funds for the Central Universities(Grant No.HIT.OCEF.2023011)China Postdoctoral Science Foundation(Grant No.2024M764172)Heilongjiang Postdoctoral Fund(Grant No.LBH-Z23144).
文摘In this paper,a novel four-prong quartz tuning fork(QTF)was designed with enlarged deformation area,large prong gap,and low resonant frequency to improve its performance in laser spectroscopy sensing.A theoretical simulation model was established to optimize the design of the QTF structure.In the simulation of quartz-enhanced photoacoustic spectroscopy(QEPAS)technology,the maximum stress and the surface charge density of the four-prong QTF demonstrated increases of 11.1-fold and 15.9-fold,respectively,compared to that of the standard two-prong QTF.In the simulation of light-induced thermoelastic spectroscopy(LITES)technology,the surface temperature difference of the four-prong QTF was found to be 11.4 times greater than that of the standard QTF.Experimental results indicated that the C_(2)H_(2)-QEPAS system based on this innovative design improved the signal-to-noise-ratio(SNR)by 4.67 times compared with the standard QTF-based system,and the SNR could increase up to 147.72 times when the four-prong QTF was equipped with its optimal acoustic micro-resonator(AmR).When the average time of the system reached 370 s,the system achieved a MDL as low as 21 ppb.The four-prong QTF-based C_(2)H_(2)-LITES system exhibited a SNR improvement by a factor of 4.52,and a MDL of 96 ppb was obtained when the average time of the system reached 100 s.The theoretical and experimental results effectively demonstrated the superiority of the four-prong QTF in the field of laser spectroscopy sensing.
基金Supported by Beijing Hospitals Authority Youth Programme,No.QML20200505.
文摘BACKGROUND Esophageal squamous cell carcinoma is a major histological subtype of esophageal cancer.Many molecular genetic changes are associated with its occurrence.Raman spectroscopy has become a new method for the early diagnosis of tumors because it can reflect the structures of substances and their changes at the molecular level.AIM To detect alterations in Raman spectral information across different stages of esophageal neoplasia.METHODS Different grades of esophageal lesions were collected,and a total of 360 groups of Raman spectrum data were collected.A 1D-transformer network model was proposed to handle the task of classifying the spectral data of esophageal squamous cell carcinoma.In addition,a deep learning model was applied to visualize the Raman spectral data and interpret their molecular characteristics.RESULTS A comparison among Raman spectral data with different pathological grades and a visual analysis revealed that the Raman peaks with significant differences were concentrated mainly at 1095 cm^(-1)(DNA,symmetric PO,and stretching vibration),1132 cm^(-1)(cytochrome c),1171 cm^(-1)(acetoacetate),1216 cm^(-1)(amide III),and 1315 cm^(-1)(glycerol).A comparison among the training results of different models revealed that the 1Dtransformer network performed best.A 93.30%accuracy value,a 96.65%specificity value,a 93.30%sensitivity value,and a 93.17%F1 score were achieved.CONCLUSION Raman spectroscopy revealed significantly different waveforms for the different stages of esophageal neoplasia.The combination of Raman spectroscopy and deep learning methods could significantly improve the accuracy of classification.
基金financial support from Science and Technology Project of Guangdong(2020B010190001)National Natural Science Foundation(12434016).
文摘Raman spectroscopy offers a great power to detect,analyze and identify molecules,and monitor their temporal dynamics and evolution when combined with single-molecule surface-enhanced Raman scattering(SM-SERS)substrates.Here we present a SM-SERS scheme that involves simultaneously giant chemical enhancement from WS22D materials,giant electromagnetic enhancement from plasmonic nanogap hot spot,and inhibition of molecular fluorescence influence under near-infrared laser illumination.Remarkably we find Coulomb attraction between analyte and gold nanoparticle can trigger spontaneous formation of molecule-hotspot pairing with high precision,stability and robustness.The scheme has enabled realization of universal,robust,fast,and large-scale uniform SM-SERS detection for three Raman molecules of rhodamine B,rhodamine 6G,and crystal violet with a very low detection limit of 10−16 M and at a very fast spectrum acquisition time of 50 ms.
基金supported by the Beijing Natural Science Foundation(Z200011,L233004)the National Key Research and Development Program(2021YFB2500300)+3 种基金the National Natural Science Foundation of China(52394170,52394171,22109011,22393900,and 22108151)the Tsinghua-Jiangyin Innovation Special Fund(TJISF)(2022JYTH0101)the S&T Program of Hebei(22344402D)the Tsinghua University Initiative Scientific Research Program.
文摘All-solid-state lithium batteries(ASSLBs)are strongly considered as the next-generation energy storage devices for their high energy density and intrinsic safety.The solid-solid contact between lithium metal and solid electrolyte plays a vital role in the performance of working ASSLBs,which is challenging to investigate quantitatively by experimental approach.This work proposed a quantitative model based on the finite element method for electrochemical impedance spectroscopy simulation of different solid-solid contact states in ASSLBs.With the assistance of an equivalent circuit model and distribution of relaxation times,it is discovered that as the number of voids and the sharpness of cracks increase,the contact resistance Rcgrows and ultimately dominates the battery impedance.Through accurate fitting,inverse proportional relations between contact resistance Rcand(1-porosity)as well as crack angle was disclosed.This contribution affords a fresh insight into clarifying solid-solid contact states in ASSLBs.
基金supported by the National Natural Science Foundation of China(Grant Nos.U21A2028,42022051,62275250,42030609,41627810,91644107,and 91544228).
文摘Atmospheric chemistry research and atmospheric measurement techniques have mutually promoted each other and developed rapidly in China in recent years.Cavity-based absorption spectroscopy,which uses a high-finesse cavity to achieve very long absorption path-length,thereby achieving ultra-high detection sensitivity,plays an extremely important role in atmospheric chemistry research.Based on the Beer–Lambert law,this technology has the unique advantages of being non-destructive,chemical-free,and highly selective.It does not require any sample preparation and can quantitatively analyze atmospheric trace gases in real time and in situ.In this paper,we review the following:(1)key technological advances in different cavity-based absorption spectroscopy techniques,including cavity ring-down spectroscopy,cavityenhanced absorption spectroscopy,cavity attenuated phase shift spectroscopy,and their extensions;and(2)applications of these techniques in the detection of atmospheric reactive species,such as total peroxy radical,formaldehyde,and reactive nitrogen(e.g.,NOx,HONO,peroxy nitrates,and alkyl nitrates).The review systematically introduces cavity-based absorption spectroscopy techniques and their applications in atmospheric chemistry,which will help promote further communication and cooperation in the fields of laser spectroscopy and atmospheric chemistry.
文摘In this editorial,we comment on the recent article by Fei et al exploring the field of near-infrared spectroscopy(NIRS)research in schizophrenia from a bibliometrics perspective.In recent years,NIRS has shown unique advantages in the auxiliary diagnosis of schizophrenia,and the introduction of bibliometrics has provided a macro perspective for research in this field.Despite the opportunities brought about by these technological developments,remaining challenges require multidi-sciplinary approach to devise a reliable and accurate diagnosis system for schizo-phrenia.Nonetheless,NIRS-assisted technology is expected to contribute to the division of methods for early intervention and treatment of schizophrenia.
基金Supported by Bissell Distinguished Professor Endowment Fund at UNC-Charlotte。
文摘Although there are numerous optical spectroscopy techniques and methods that have been used to extract the fundamental bandgap of a semiconductor,most of them belong to one of these three approaches:(1)the excitonic absorption,(2)modulation spectroscopy,and(3)the most widely used Tauc-plot.The excitonic absorption is based on a many-particle theory,which is physically the most correct approach,but requires more stringent crystalline quality and appropriate sample preparation and experimental implementation.The Tauc-plot is based on a single-particle theo⁃ry that neglects the many-electron effects.Modulation spectroscopy analyzes the spectroscopy features in the derivative spectrum,typically,of the reflectance and transmission under an external perturbation.Empirically,the bandgap ener⁃gy derived from the three approaches follow the order of E_(ex)>E_(MS)>E_(TP),where three transition energies are from exci⁃tonic absorption,modulation spectroscopy,and Tauc-plot,respectively.In principle,defining E_(g) as the single-elec⁃tron bandgap,we expect E_(g)>E_(ex),thus,E_(g)>E_(TP).In the literature,E_(TP) is often interpreted as E_(g),which is conceptual⁃ly problematic.However,in many cases,because the excitonic peaks are not readily identifiable,the inconsistency be⁃tween E_(g) and E_(TP) becomes invisible.In this brief review,real world examples are used(1)to illustrate how excitonic absorption features depend sensitively on the sample and measurement conditions;(2)to demonstrate the differences between E_(ex),E_(MS),and E_(TP) when they can be extracted simultaneously for one sample;and(3)to show how the popular⁃ly adopted Tauc-plot could lead to misleading results.Finally,it is pointed out that if the excitonic absorption is not ob⁃servable,the modulation spectroscopy can often yield a more useful and reasonable bandgap than Tauc-plot.
基金supported by a joint project with SINOPEC(Dalian)Research Institute of Petroleum and Petrochemicals Co.,Ltd.(Contract No.323061).
文摘In the near-infrared(NIR)spectroscopic data of complex sample systems,such as tobacco leaves,nonlinearity is fairly significant between the absorbance and concentration.This nonlinearity severely degrades the quantitative results of traditional methods,such as partial least squares regression(PLS),which can be used to construct linear models.The problem was addressed in this study by using deep learning(DL).We employed three different DL models:a one-dimensional convolutional neural network(1D CNN),a deep neural network(DNN),and a stacked autoencoder with feedforward neural networks(SAE-FNNs).By carefully selecting and tuning the architectures and parameters of these models,we were able to find the most suitable model for dealing with such nonlinear relationships.Our experimental findings reveal that both the DNN and the SAE-FNN models excel in addressing the nonlinear issues of pectin concentration in tobacco,surpassing the performance of the classic linear model(PLS).Specifically,the DNN model stands out for its low average root mean squared error of prediction(RMSEP)value and small standard deviation(SD)of RMSEPs,leading to a tighter and more centered distribution of residuals in the prediction set.These DL models not only proficiently identify complex patterns within NIR data but also boast high prediction accuracy and fast implementation,demonstrating their effectiveness in analytical applications.
基金Supported by the National Key R&D Program of China(2023YFD2101001)National Natural Science Foundation of China(32202144,61807001)。
文摘To address the issues of peak overlap caused by complex matrices in agricultural product terahertz(THz)spectral signals and the dynamic,nonlinear interference induced by environmental and system noise,this study explores the feasibility of adaptive-signal-decomposition-based denoising methods to improve THz spectral quality.THz time-domain spectroscopy(THz-TDS)combined with an attenuated total reflection(ATR)accessory was used to collect THz absorbance spectra from 48 peanut samples.Taking the quantitative prediction model of peanut moisture content based on THz-ATR as an example,wavelet transform(WT),empirical mode decomposition(EMD),local mean decomposition(LMD),and its improved methods-segmented local mean decomposition(SLMD)and piecewise mirror extension local mean decomposition(PME-LMD)-were employed for spectral denoising.The applicability of different denoising methods was evaluated using a support vector regression(SVR)model.Experimental results show that the peanut moisture content prediction model constructed after PME-LMD denoising achieved the best performance,with a root mean square error(RMSE),coefficient of determination(R^(2)),and mean absolute percentage error(MAPE)of 0.010,0.912,and 0.040,respectively.Compared with traditional methods,PME-LMD significantly improved spectral quality and model prediction performance.The PME-LMD denoising strategy proposed in this study effectively suppresses non-uniform noise interference in THz spectral signals,providing an efficient and accurate preprocessing method for THz spectral analysis of agricultural products.This research provides theoretical support and technical guidance for the application of THz technology for detecting agricultural product quality.
基金supported by National Natural Science Foundation of China(Grant No.:32301161)the Natural Scientific Foundation of Hunan Province,China(Grant No.:2023JJ60052)+3 种基金the Scientific Research Project of Hunan Provincial Health Commission,China(Grant No.:202112062218,20190161)the Scientific Research Project of Hunan Provincial Department of Education,China(Grant No.:22B0455)the Clinical“4310”Project of the University of South China,China(Grant No.:20224310NHYCG02)the Doctoral Scientific Research Foundation of University of South China,China(Grant No.:200XQD042).
文摘Infrared(IR)spectroscopy,a technique within the realm of molecular vibrational spectroscopy,furnishes distinctive chemical signatures pivotal for both structural analysis and compound identification.A notable challenge emerges from the misalignment between the mid-IR light wavelength range and molecular dimensions,culminating in a constrained absorption cross-section and diminished vibrational absorption coefficients(Supplementary data).
文摘This communication looks at the photo-oxidation of polythene and polypropylene plastic bottle tops that are placed on soil in a hot arid environment. The degree of oxidation of the plastic is monitored by FT-IR spectroscopy. It is noted that while different bottle top types photo-oxidize at different rates, all show an appreciable level of oxidation after half a year of exposure to the environment. The oxidation leads to brittleness of the plastic, which leads to fissure formation in bottle tops of little thickness. This leads to fragmentation of the material upon impact, making plastic bottle tops an appreciable source of microplastics.
基金supported by grants from the National Natural Science Foundation of China(Nos.22074015 and 82074428)Youth Talent Cultivation Initiation Fund of Zhongda Hospital,Southeast University(No.CZXM-GSP-RC110)to Hao Li+1 种基金Evidence-Based Capacity Building for TCM Specialty Therapies for Skin Diseases of National Administration of TCMInnovative Team Projects of Shanghai Municipal Commission of Health(No.2022CX011)to Fulun Li.
文摘Antifungal resistance is the leading cause of antifungal treatment failure in invasive candidiasis.Metabolic rewiring could become a new insight to account for antifungal resistance as to find innovative clinical therapies.Here,we show that dynamic surface-enhanced Raman spectroscopy is a promising tool to identify the metabolic differences between fluconazole(Diflucan)-resistant and fluconazole(Diflucan)-sensitive Candida albicans through the signatures of biochemical components and complemented with machine learning algorithms and two-dimensional correlation spectroscopy,an underlying resistance mechanism,that is,the change of purine metabolites induced the resistance of Candida albicans has been clarified yet never reported anywhere.We hope the integrated methodology introduced in this work could be beneficial for the interpretation of cellular regulation,propelling the development of targeted antifungal therapies and diagnostic tools for more efficient management of severe antifungal resistance.
基金The National Key R&D Program of China(No.2022YFE0113000)the National Science Fund for Distinguished Young Scholars(No.22025406)+1 种基金the National Natural Science Foundation of China(Nos.22074138,12174457)the Youth Innovation Promotion Association of CAS(No.2020233)for financial support。
文摘Revealing the factors that affect the vibrational frequency of Stark probe at interface is a pre-requirement for evaluating the absolute interfacial electric field.Here using surface-enhanced infrared absorption(SEIRA)spectroscopy,attenuated total reflection(ATR)spectroscopy and molecular dynamics(MD),we reveal the assembled C≡N at gold nanofilm exhibits a reduced Stark tuning rate(STR)referring to the vibrational frequency shift in response to electric field comparing with the bulk which was regulated by the electron transfer between S and Au.These findings lead to a deeper understanding of the vibrational Stark effect at the interface and provide guidance for improving the interface electric field theory.
基金Supported by Hunan Provincial Scientific Research Plan Project of Traditional Chinese MedicineNational Natural Science Foundation of China,No.82371521Special Tasks for the Construction of Hunan Innovative Province,No.2023SK4002.
文摘BACKGROUND Many patients with coronavirus disease 2019(COVID-19)may experience emotional issues and cognitive impairment.However,it remains unclear whether the brain mediates the impact of COVID-19 on the emergence of psychopathological symptoms.It remains unclear whether anxiety and depression are caused by stressors or viral infection.AIM To use functional near-infrared spectroscopy(fNIRS)to detect cortical hemodynamic changes in patients with COVID-19 and their relationship with mental symptoms(mainly depression and anxiety),to investigate whether COVID-19 causes these changes by affecting brain function.METHODS A total of 58 subjects,comprising 29 patients with first acute COVID-19 infection and 29 healthy controls without COVID-19 infection and without anxiety or depression were recruited.Then cortical activation during the performance of the verbal fluency test(VFT)and brain connectivity during the resting state(rs)were evaluated by 53-channel fNIRS.For the COVID-19-infected group,Patient Health Questionnaire-9(PHQ-9)and General Anxiety Disorder-7(GAD-7)were used to assess the emotional state before fNIRS measures.RESULTS For the rs,compared to the uninfected group,the infected group exhibited lower rs functional connectivity(FC)in the dorsolateral prefrontal cortex(DLPFC),which was correlated with both the PHQ score and GAD score.During the VFT,the infected group exhibited significantly lower cortical activation than the uninfected group in both Broca-left and Broca-right.Besides,the integral value in the DLPFC-L showed a significant negative correlation with the PHQ-9 score during the VFT in the infected group.CONCLUSION There were significant differences in the bilateral Broca area and DLPFC between the COVID-19-infected and uninfected groups,which may be the reason why COVID-19 infection impairs cognitive function and language function and leads to psychiatric symptoms.In addition,the rsFC in patients with COVID-19 was positively correlated with the severity of depression and anxiety,which may be related to the fact that the mental symptoms of patients with COVID-19 are characterized by depression and anxiety,rather than depression or anxiety alone.Our study provides evidence that the psychological and emotional issues caused by COVID-19 are not only due to external social factors but also involve more direct brain neural mechanisms and abnormal neural circuits,which also provide insights into the future treatment and prognosis of individuals with COVID-19.
基金supported by the Vinnova(project number 2020-03778)supported by the Swedish Research Council(Vetenskapsradet,project number 2021-04157).
文摘Nano-scale chemical inhomogeneity in surface oxide films formed on a V-and N-containing martensite stainless steel and tempering heating induced changes are investigated by a combination of synchrotron-based hard X-ray Photoelectron emission spectroscopy(HAXPES)and microscopy(HAXPEEM)as well as microscopic X-ray absorption spectroscopy(μ-XAS)techniques.The results reveal the inhomogeneity in the oxide films on the micron-sized Cr_(2)N-and VN-type particles,while the inhomogeneity on the martensite matrix phase exists due to localised formation of nano-sized tempering nitride particles at 600℃.The oxide film formed on Cr_(2)N-type particles is rich in Cr_(2)O_(3) compared with that on the martensite matrix and VN-type particles.With the increase of tempering temperature,Cr_(2)O_(3) formation is faster for the oxidation of Cr in the martensite matrix than the oxidation of Cr nitride-rich particles.
基金supported by the National Natural Science Foundation of China[52125307(to P.G.),12404192(to R.C.S),12274061(to L.Q.)]Key Research and Development Program from the Ministry of Science and Technology(2023YFA1406301)the support from the New Cornerstone Science Foundation through the XPLORER PRIZE。
文摘The infinite-layer nickelates,proposed as analogs to superconducting cuprates,provide a promising platform for exploring the mechanisms of unconventional superconductivity.However,the superconductivity has been exclusively observed in thin films under atmospheric pressure,underscoring the critical role of the heterointerface.
基金Jingzhou Science and Technology Plan Project,Hubei Province(2024HD71)。
文摘Background:The brain,which constitutes merely 2%of total body weight,receives approximately 15%of cardiac output and consumes about 20%of the body's oxygen,rendering it highly susceptible to hypoxia.Short-term oxygen deprivation can lead to irreversible damage.Near-infrared spectroscopy(NIRS),operating within the 650–1100 nm wavelength range,enables non-invasive,continuous monitoring of cerebral tissue oxygen saturation(rSO_(2)).It has been extensively utilised in intensive care units,neurosurgery,cardiovascular surgery,and perioperative anaesthesia management.Recent advancements in domestically produced devices have progressed rapidly;however,variations in wavelength,sensor design,and algorithms across different brands mean that measurement values are not interchangeable.The accuracy and sensitivity of these devices necessitate comprehensive validation.Objective:This study aimed to evaluate the measurement performance of the domestically produced cerebral tissue oxygen saturation monitor(MOC200),determine its consistency and clinical applicability compared to the imported device(INVOS5100C),and investigate physiological factors influencing baseline rSO_(2)values.Method:A total of 222 healthy subjects aged 15 to 90 years were enrolled from January to March 2025.rSO_(2)was measured using both the MOC200 and INVOS5100C devices.Device performance was assessed via correlation analysis,linear regression,Bland-Altman agreement analysis,and difference testing.Results:Measurement values from MOC200 and INVOS5100C demonstrated high consistency,with a correlation coefficient of 0.786.Bland-Altman analysis indicated greater agreement for left hemisphere measurements,while right hemisphere and mean values exhibited relatively lower consistency.Age,gender,and haemoglobin levels are the primary factors influencing baseline rSO_(2)values,with haemoglobin showing a positive correlation,whereas increasing age and female gender are associated with lower rSO_(2)levels.Conclusion:The domestically developed MOC200 cerebral tissue oxygen saturation monitor reliably reflects cerebral oxygenation in healthy individuals,exhibiting accuracy and stability comparable to the imported device and demonstrating good measurement consistency.Age,sex,and haemoglobin are key physiological factors influencing baseline rSO_(2)in this population.
