24,875 results match your criteria reflectance

Performance Improvement of Triplet-Triplet Annihilation-Based Upconversion Solid Films through Plasmon-Induced Backward Scattering of Periodic Arrays of Ag and Al.

Langmuir 2021 Sep 20. Epub 2021 Sep 20.

Department of Materials and Applied Chemistry, Nihon University, Chiyoda, Tokyo 101-8308, Japan.

The performance improvement of solid-state triplet-triplet annihilation-based photon upconversion (TTA-UC) systems is required for the application to various solar devices. The performance can be improved by making use of the local strong electric field generated through the excitation of localized surface plasmon (LSP) resonance of metal nanostructures. However, since the improvement is effective only within the limited nanospace around nanoparticles (, the near-field effect), a methodology for improving the performance over a wider spatial region is desirable. Read More

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September 2021

Visualizing veins from color images under varying illuminations for medical applications.

J Biomed Opt 2021 Sep;26(9)

Nanjing University of Aeronautics and Astronautics, College of Automation Engineering, Nanjing, Jian, China.

Significance: Effective vein visualization is critically important for several clinical procedures, such as venous blood sampling and intravenous injection. Existing technologies using infrared device or ultrasound rely on professional equipment and are not suitable for daily medical care. A regression-based vein visualization method is proposed. Read More

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September 2021

PLS-DA and data fusion of visible Reflectance, XRF and FTIR spectroscopy in the classification of mixed historical pigments.

Spectrochim Acta A Mol Biomol Spectrosc 2021 Sep 10;265:120384. Epub 2021 Sep 10.

Laboratório de Instrumentação e Simulação Computacional. LISCOMP/IFRJ-CPAR, 26600-000, Paracambi, Brazil. Electronic address:

In this work samples of historical pigments of green hue were brushed on a canvas and studied by Visible Reflectance, X-Ray Fluorescence and Fourier Transform Infrared Spectroscopy. One hundred samples were investigated, all with green hue, these prepared from pigments themselves green, such as chromium oxide (CrO) or from a mixture of pigments that result in green, for example, chrome yellow (PbCrO) and Prussian blue (Fe[Fe(CN)]). Because every sample investigated through the spectroscopic techniques were of green hue, the characterization of the pigments present in the mixtures through the visual inspection of spectra has become a complex task in some cases, also, due the large number of recorded spectra. Read More

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September 2021

Foliar optical traits capture physiological and phenological leaf plasticity in Tilia×euchlora in the urban environment.

Sci Total Environ 2021 Sep 11;805:150219. Epub 2021 Sep 11.

Department of Earth and Environmental Sciences, KU Leuven, 3001 Heverlee, Belgium. Electronic address:

Knowledge on the response of trees to the urban heat island (UHI) effect and soil sealing is currently limited, yet of vital importance in an era characterized by both climate change and urbanization. We investigated the physiological and phenological leaf plasticity of Tilia×euchlora trees to the UHI effect and soil sealing and explored the potential of leaf optical traits to quantify the magnitude of leaf plasticity. Temporal changes of leaf water content (LWC), specific leaf area (SLA), total chlorophyll (Chl) and carotenoids (Car) content, Car:Chl ratio and leaf reflectance for 46 Tilia×euchlora trees were measured along a soil sealing and urbanization gradient. Read More

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September 2021

Estimating the catechin concentrations of new shoots in green tea fields using ground-based hyperspectral imagery.

Food Chem 2021 Aug 31;370:130987. Epub 2021 Aug 31.

Research Organization of Science and Technology, Ritsumeikan University, 1-1-1 Noji-higashi, Kusatsu, Shiga 525-8577, Japan.

Hyperspectral imagery was applied to estimating non-galloyl (EC, EGC) and galloyl (ECG, EGCG) types of catechins in new shoots of green tea. Partial least squares regression models were developed to consider the effects of commercial fertilizer (CF) and organic fertilizer (OF). The models could explain each type of catechin with a precision of more than 0. Read More

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Photodynamic therapy combined with carbon dioxide laser for successful treatment of cutaneous squamous cell carcinoma within a long-stand and huge seborrheic keratosis.

Photodiagnosis Photodyn Ther 2021 Sep 15:102536. Epub 2021 Sep 15.

Institute of Photomedicine, Shanghai Skin Disease Hospital, School of Medicine, Tongji University, Shanghai 200092, China. Electronic address:

Seborrheic keratosis (SK) is a common benign lesion in which malignancies like cutaneous squamous cell carcinoma (cSCC) can arise rarely. We report a case of an 81-year-old man who presented a well-demarcated reddish-brown plaque with central raised coarse nodules on the top of his head. Dermoscopy and reflectance confocal microscopy (RCM) showed the possibility of malignant transformation. Read More

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September 2021

The study of Dominican amber-bearing sediments from Siete Cañadas and La Cumbre with a discussion on their origin.

Sci Rep 2021 Sep 17;11(1):18556. Epub 2021 Sep 17.

Residencial Rosmil, Los restauradores Calle 3 casa #7, Altos Distrito Nacional, Dominican Republic.

The paper presents comprehensive mineralogical and geochemical characteristics of Dominican amber-bearing sediments from Siete Cañadas, Hato Mayor Province of the Eastern Mining District (EMD) in the Cordillera Oriental. The characteristics of rocks collected from the borehole in Siete Cañadas area (EMD) were compared with petrography of coaly shales from La Cumbre in the Northern Mining District (NMD). The mineralogy of the rocks was determined using transmitted and reflected light microscopy, scanning electron microscopy, Powder X-ray diffraction and Fourier Transform Raman Spectroscopy. Read More

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September 2021

Impairments of cerebral blood flow microcirculation in rats brought on by cardiac cessation and respiratory arrest.

J Biophotonics 2021 Sep 17:e202100216. Epub 2021 Sep 17.

Histology, Cytology and Embryology Department, I.M. Sechenov First Moscow State Medical University, Moscow, Russia.

The impairments of cerebral blood flow microcirculation brought on by cardiac and respiratory arrest were assessed with multi-modal diagnostic facilities, utilising laser speckle contrast imaging, fluorescence spectroscopy and diffuse reflectance spectroscopy. The results of laser speckle contrast imaging show a notable reduction of cerebral blood flow in small and medium size vessels during a few minutes of respiratory arrest, while the same effect was observed in large sinuses and their branches during the circulatory cessation. Concurrently, the redox ratio assessed with fluorescence spectroscopy indicates progressing hypoxia, NADH accumulation and increase of FAD consumption. Read More

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September 2021

Diagnosis of cadmium contamination in urban and suburban soils using visible-to-near-infrared spectroscopy.

Environ Pollut 2021 Sep 9;291:118128. Epub 2021 Sep 9.

Department of Environment, Ghent University, Coupure Links 653, 9000, Gent, Belgium.

Previous studies have mostly focused on using visible-to-near-infrared spectral technique to quantitatively estimate soil cadmium (Cd) content, whereas little attention has been paid to identifying soil Cd contamination from a perspective of spectral classification. Here, we developed a framework to compare the potential of two spectral transformations (i.e. Read More

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September 2021

Severe COVID-19 and Retina: Are There Any Retinal Manifestations?

Klin Monbl Augenheilkd 2021 Sep 15. Epub 2021 Sep 15.

Infectious Diseases and Clinical Microbiology, Kayseri City Education and Research Hospital, Kayseri, Turkey.

Purpose: To investigate whether there are retinal lesions associated with severe COVID-19.

Methods: We studied 232 symptomatic subjects aged 18 - 65 years who had severe COVID-19 and had received treatment. The evaluations included ophthalmological examinations, optical coherence tomography (OCT), imaging modalities with near infrared reflectance (NIR), fundus autofluorescence (FAF), and fundus photography (FP). Read More

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September 2021

Altered albedo dominates the radiative forcing changes in a subtropical forest following an extreme snow event.

Glob Chang Biol 2021 Sep 15. Epub 2021 Sep 15.

Indian Institute of Tropical Meteorology, Ministry of Earth Sciences, Pune, 411008, India.

Subtropical forests are important ecosystems globally due to their extensive role in carbon sequestration. Extreme climate events are known to introduce disturbances in the ecosystem that cause long-term changes in carbon balance and radiation reflectance. However, how these ecosystem function changes contribute to global warming in terms of radiative forcing (RF), especially in the years following a disturbance, still needs to be investigated. Read More

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September 2021

Kinetics and energetic analysis of the slow dispersive electron transfer from nano-TiO to O by diffusion reflectance and Laplace transform.

Phys Chem Chem Phys 2021 Sep 15;23(35):19901-19910. Epub 2021 Sep 15.

State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan City, Hubei Province 430070, P. R. China.

Electron transfer to O is a universally existing process for the physiochemistry of many materials. Electron transfer to O is also an inevitable process for photocatalytic reactions over TiO and other materials. In the present research, a diffusion reflectance system was developed to measure optical diffusion reflectances caused by photoinduced electrons in nano-TiO under a steady light illumination; absorption decays can be obtained to study the electron transfer from their trapped states to O. Read More

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September 2021

Circularly polarized optical microscope using a low aberration liquid crystal lens.

Opt Lett 2021 Sep;46(18):4434-4437

We demonstrate a circularly polarized optical microscope (POM) by incorporating a hole-patterned electrode (HPE) liquid crystal (LC) lens fabricated by photoalignment. The focal plane is controlled by voltages on the HPE LC lens with a tuning range of 2.2 mm without any mechanical movement. Read More

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September 2021

Case Report: Multimodal Imaging of Acute Idiopathic Maculopathy in a Chinese Woman.

Optom Vis Sci 2021 Sep 14. Epub 2021 Sep 14.

Department of Pathology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, People's Republic of China Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, Hunan, People's Republic of China Department of Ophthalmology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, People's Republic of China Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin

Significance: Acute idiopathic maculopathy is a rare disease with the characteristics of sudden, severe, unilateral central vision loss after a flu-like illness. The prognosis is generally good, and poor vision usually results from complications such as choroidal neovascularization or subfoveal pigment degeneration. Multimodal imaging is helpful in the diagnosis and follow-up of this disease. Read More

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September 2021

Photonic Particles Made By The Confined Self-assembly of A Supramolecular Comb-like Block Copolymer.

Macromol Rapid Commun 2021 Sep 15:e2100522. Epub 2021 Sep 15.

Adolphe Merkle Institute, University of Fribourg, Fribourg, Switzerland.

Approaches that enable the preparation of robust polymeric photonic particles are of interest for the development of non-fading and highly reflective pigments for applications such as paints and display technologies. Here, we report the preparation of photonic particles that display structural color in both, aqueous suspension and the dry solid state. This was achieved by exploiting the confined self-assembly of a supramolecular comb-like block copolymer (BCP) that microphase separates into a well-ordered lamellar morphology with dimensions that promote a photonic band gap in the visible range. Read More

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September 2021

Structure and Optical Properties of Hybrid-Layered-Double Perovskites (CHN)AgMBr (M = In, Sb, and Bi).

Inorg Chem 2021 Sep 15. Epub 2021 Sep 15.

Department of Chemistry, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing 100083, China.

The Pb-free hybrid-layered-double perovskites (HLDPs) have been proposed as green and stable semiconducting materials for optoelectronic devices, but the synthesized members are still limited. Here, we report the synthesis of three new HLDPs, (CHN)AgMBr (M = In, Sb, and Bi), by a solution method using 1,4-bis(ammoniomethyl)cyclohexane (CHN) as the organic spacing cation. All three of these HLDPs show ⟨100⟩-oriented layered structures with Ag and In/Sb/Bi order arranged in corner-sharing octahedral layers. Read More

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September 2021

Detecting antimicrobial resistance in using benchtop attenuated total reflectance-Fourier transform infrared spectroscopy and machine learning.

Analyst 2021 Sep 15. Epub 2021 Sep 15.

Centre for Clinical Research, Faculty of Medicine, The University of Queensland, Herston, QLD, 4006, Australia.

The widespread dissemination of resistance to third-generation cephalosporins in the through the production of extended-spectrum β-lactamase (ESBL) is considered a critical global crisis requiring urgent attention of clinicians and scientists alike. Rapid diagnostic methods that can identify microbial resistance profiles closer to the point of care are crucial to minimize the overuse of antimicrobial agents and improve patient outcomes. Although Fourier transform infrared (FTIR) microscopy has shown promise in distinguishing between bacterial species, the high cost and technical requirements of the IR microscope may limit broad clinical use. Read More

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September 2021

Reflectance confocal findings in a large-cell acanthoma with histologic correlation.

JAAD Case Rep 2021 Oct 21;16:65-68. Epub 2021 Aug 21.

Department of Cutaneous Oncology, Scully Welsh Cancer Center, Cleveland Clinic Indian River Hospital, Vero Beach, Florida.

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October 2021

Macrophage targeted theranostic strategy for accurate detection and rapid stabilization of the inflamed high-risk plaque.

Theranostics 2021 18;11(18):8874-8893. Epub 2021 Aug 18.

Multimodal Imaging and Theranostic Lab., Cardiovascular Center, Korea University Guro Hospital, Seoul, South Korea.

Inflammation plays a pivotal role in the pathogenesis of the acute coronary syndrome. Detecting plaques with high inflammatory activity and specifically treating those lesions can be crucial to prevent life-threatening cardiovascular events. Here, we developed a macrophage mannose receptor (MMR)-targeted theranostic nanodrug (mannose-polyethylene glycol-glycol chitosan-deoxycholic acid-cyanine 7-lobeglitazone; MMR-Lobe-Cy) designed to identify inflammatory activity as well as to deliver peroxisome proliferator-activated gamma (PPARγ) agonist, lobeglitazone, specifically to high-risk plaques based on the high mannose receptor specificity. Read More

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Spectral responses in rangelands and land cover change by livestock in regions of the Caatinga biome, Brazil.

Sci Rep 2021 Sep 14;11(1):18261. Epub 2021 Sep 14.

Federal University of Ceará, Fortaleza, 60440-900, Brazil.

This study aimed to analyze fragments of rangelands through spectral responses and land cover change by livestock in regions of the Caatinga biome through remote sensing. For spectral behavior, the surface reflectance bidirectional (SRB) and spectral indexes of vegetation were used to verify the ragelands seasonality. Land cover change detection of Ouricuri and Tauá through Landsat-8 images with a 16-day revisit interval, were processed in the Google Earth Engine platform (GEE) and software Quantum GIS version 2. Read More

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September 2021

Form quantitation in desmotropic mixtures of albendazole bulk drug by chemometrics-assisted analysis of vibrational spectra.

Spectrochim Acta A Mol Biomol Spectrosc 2021 Sep 4;265:120354. Epub 2021 Sep 4.

Área de Análisis de Medicamentos, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario e Instituto de Química Rosario (IQUIR, CONICET-UNR), Suipacha 531, Rosario S2002LRK, Argentina. Electronic address:

Albendazole is a benzimidazole-type active pharmaceutical ingredient, and one of the most effective broad-spectrum anthelminthic agents. The drug has two solid-state forms (ALB I and ALB II) which are desmotropes; both of them seem to be currently marketed. However, using the wrong crystalline solid form for formulation may have an undesired impact on the physicochemical and/or bioavailability properties of the drug product. Read More

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September 2021

In vivo MRI detection of intraplaque macrophages with biocompatible silica-coated iron oxide nanoparticles in murine atherosclerosis.

J Appl Biomater Funct Mater 2021 Jan-Dec;19:22808000211014751

Research Center for Bioconvergence Analysis, Korea Basic Science Institute, Cheongju, Republic of Korea.

Identification of a vulnerable atherosclerotic plaque before rupture is an unmet clinical need. Integrating nanomedicine with multimodal imaging has the potential to precisely detect biological processes in atherosclerosis. We synthesized silica-coated iron oxide nanoparticles (SIONs) coated with rhodamine B isothiocyanate and polyethylene glycol and investigated their feasibility in the detection of macrophages in inflamed atherosclerotic plaques of apolipoprotein E-deficient (ApoE) mice via magnetic resonance (MR) and fluorescence reflectance (FR) imaging. Read More

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September 2021

CdS Reinforced with CoSX/NiCo-LDH Core-shell Co-catalyst Demonstrate High Photocatalytic Hydrogen Evolution and Durability in Anhydrous Ethanol.

Chemistry 2021 Sep 14. Epub 2021 Sep 14.

North Minzu University, School of Chemistry and Chemical Engineering, No:204 Wenchang Road, 750021, Yinchuan, CHINA.

At present, inefficient charge separation of single photocatalyst impedes the development of photocatalytic hydrogen evolution. In this work, the CoS X /NiCo-LDH core-shell co-catalyst was cleverly designed, which exhibit high activity and high stability of hydrogen evolution in anhydrous ethanol system when coupled with CdS. Under visible light (λ ≥ 420 nm) irradiation, the 3%Co/NiCo/CdS composite photocatalyst exhibits a surprisingly high photocatalytic hydrogen evolution rate of 20. Read More

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September 2021

Self-supported 3D reduced graphene oxide for solid-phase extraction: An efficient and low-cost sorbent for environmental contaminants in aqueous solution.

Talanta 2021 Dec 31;235:122750. Epub 2021 Jul 31.

Instituto de Química, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves, 9500, Bairro Agronomia, Porto Alegre, RS, 91501-970, Brazil. Electronic address:

A 3D reduced graphene oxide (3D-rGO), a self-supported, efficient, and low-cost sorbent, was synthesised and employed in a solid-phase extraction (SPE) cartridge. As a proof of concept, it was applied to remove diclofenac from aqueous solution. After applying statistical methods to systematically investigate key parameters for optimizing the 3D-rGO cartridge performance, it reached removal and elution efficiencies of 100 % and 90 %, respectively. Read More

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December 2021

Mesoporous poorly crystalline α-FeO with abundant oxygen vacancies and acid sites for ozone decomposition.

Sci Total Environ 2021 Sep 7;804:150161. Epub 2021 Sep 7.

State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China; Quanzhou Institute for Environmental Protection Industry, Nanjing University, Beifeng Road, Quanzhou 362000, China. Electronic address:

In this work, mesoporous poorly crystalline hematite (α-FeO) was prepared using mesoporous silica (KIT-6) functionalized with 3-[(2-aminoethyl)amino]propyltrimethoxysilane as a hard template (SMPC-α-FeO). The disordered atomic arrangement structure of SMPC-α-FeO promoted the formation of oxygen vacancies, which was confirmed using X-ray photoelectron spectroscopy (XPS), O-temperature-programmed desorption (TPD), H-temperature-programmed reduction (TPR), and in situ diffuse reflectance infrared Fourier transform (DRIFT) analyses. Density functional theory calculations (DFT) also proved that reducing the crystallinity of α-FeO decreased the formation energy of oxygen vacancies. Read More

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September 2021

Assessing Light and Energy-Based Therapy by Optical Coherence Tomography and Reflectance Confocal Microscopy: A Randomized Trial of Photoaged Skin.

Dermatology 2021 Aug 27:1-8. Epub 2021 Aug 27.

Department of Dermatology, Copenhagen University Hospital, Bispebjerg and Frederiksberg, Copenhagen, Denmark.

Background And Objectives: Image-guided quantitative and semi-quantitative assessment of skin can potentially evaluate treatment efficacy. Optical coherence tomography (OCT) and reflectance confocal microscopy (RCM) are ideal for this purpose. This study assessed clinically relevant statistical changes in RCM and OCT features in photoaged skin after light and energy-based therapy. Read More

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Mueller matrix polarimetry and polar decomposition of articular cartilage imaged in reflectance.

Biomed Opt Express 2021 Aug 22;12(8):5160-5178. Epub 2021 Jul 22.

Department of Biomedical Engineering, The Catholic University of America, 620 Michigan Avenue NE, Washington, DC 20064, USA.

Articular cartilage birefringence relates to zonal architecture primarily of type II collagen, which has been assessed extensively in transmission, through thin tissue sections, to evaluate cartilage repair and degeneration. Mueller matrix imaging of articular cartilage in reflection is of potential utility for non-destructive imaging in clinical and research applications. Therefore, such an imaging system was constructed to measure laser reflectance signals, calibrated, and tested with optical standards. Read More

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Handheld spatial frequency domain imager for noninvasive Sjögren's syndrome labial salivary gland biopsy.

Biomed Opt Express 2021 Aug 20;12(8):5057-5072. Epub 2021 Jul 20.

Institute of Lasers and Biomedical Photonics, Biomedical Engineering College, Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China.

A labial salivary gland biopsy (LSGB) plays an essential role in diagnosing Sjögren's syndrome (SS), but its clinical application is limited due to its invasiveness. Here, we present a handheld single snapshot multiple-frequency demodulation-spatial frequency domain imaging (SSMD-SFDI) device for a rapid optical biopsy of labial salivary glands noninvasively. The structural and physiological parameters of lower lip mucosa were obtained from the light reflectance of the layered oral mucosa. Read More

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Monitoring adaptation of skin tissue oxygenation during cycling ergometer exercise by frequency-domain diffuse optical spectroscopy.

Biomed Opt Express 2021 Aug 19;12(8):5023-5035. Epub 2021 Jul 19.

College of Photonics, National Yang Ming Chiao Tung University, Tainan, 71150, Taiwan.

In addition to supplying oxygen molecule O for metabolic functions during the adaptation to exercise, blood also plays a critical role in heat dissipation for core temperature stabilization. This study investigates the status of hemodynamic oxygenation in the forearm's skin tissue of three participants during a complete ergometer exercise from the resting to exercising, and to recovering conditions using a three-wavelength frequency-domain diffuse reflectance spectroscopy (FD DRS) alongside the monitoring of heartbeat rate and skin temperature. The FD DRS system was synchronized with radiofrequency (RF)-modulated input photon sources and the respective output to extract time-course absorption and scattering coefficients of the skin tissue, which, through the fitting of lambert's law of absorbance, can be used to determine the concentration of oxygenated/deoxygenated hemoglobin molecules, and consequentially, the oxygen saturation of skin tissue and total hemoglobin (THb) concentration. Read More

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