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- 2019
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- infrared image
- target detection
- lucas–kanade method (LK)
- local contrast method (LCM)
- facet model
- target detection
- zero-crossing point
- Image processing
- Infrared camera
- Eye movement
- Optoelectronic Information Science and Engineering
- Chinese Academy of Sciences
- Gunma University
- University of Chinese Academy of Science
- Xi’an Institute of Optics and Precision Mechanics Chinese Academy of Science
- University of Science and Technology of China
- Space Star Technology Co. LTD
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Application of Biophotonics with Near Infrared Excitation for Theranostics; 近赤外励起バイオフォトニクスのセラノスティクスへの展開;
摘要： Near infrared wavelength region is known to have the most transparency of live body for electromagnetic wave with wavelength around the visible wavelength. Namely, the near infrared with a wavelength longer than 1000 nm (OTN-NIR) shows more transparency than that with shorter wavelength. The observation depth can be several centimeters with the OTN-NIR fluorescence, while that is limited to be only several millimeters with visible fluorescence. As OTN-NIR fluorescent agents, dyes, quantum dots, carbon nanotubes and rare-earth doped ceramic nanoparticles (RED-CNP) are known. A special feature of the RED-CNP is to show infrared-to-visible upconversion to emit visible light with a near infrared excitation, simultaneously with the OTN-NIR fluorescence. As a theranostic approach, nanomaterials for achieving photodynamic therapy with the near infrared excitation are introduced. Another special feature of the RED-CNP is the potential use for fluorescence nanothermometry. A scheme for ratiometric fluorescence nanothermometry with the OTN-NIR fluorescence is described. By using a RED-CNP with holomium and erbium co-doping, ratiometric fluorescence nanothermometry was successfully demonstrated. As shown with the case of photodynamic therapy with near infrared excitation, by applying an upconversion excitation scheme, visible light emission for photochemical reaction is possible with a near infrared excitation with high transparency in a live body. By constructing these multiple functions on the RED-CNP, various theranostic approach can be achieved. The size and bio distribution controls are important issues for applications of the RED-CNP for medical applications.
关键词： thermometry,near infrared,nanoparticle,rare-earth,PDT
更新于2025-09-09 09:28:46
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Fourier Transform Infrared Spectroscopy: Applications in Medicine
摘要： Fourier transform infrared spectroscopy (FTIR) is rapidly gaining ground in modern clinical research. This technique is useful for understanding a wide variety of applications ranging from characterization and quality control of various compounds to biomedicine. Importantly, biological materials like proteins, carbohydrates, lipids and nucleic acids have unique structures so it is possible to obtain spectral fingerprints corresponding to their functional groups. FTIR spectroscopic techniques generate an immediate appeal in the field of biology and medicine because of their fast and non-invasive nature. It allows easy visualization of cellular components based on their intrinsic properties and chemical composition. It provides a potential route to screen diagnostic markers for diseases like cancer. FTIR spectroscopy is also considered as a useful tool for analysis of the chemical composition of human calculi. Analysis of stone samples from recurrent stone formers by FTIR may provide a clue to effective prevention of stone recurrence [1]. Fourier transform infrared (FT-IR) spectroscopy has proven to be a fundamental and valuable technique in biology and medicine due to its high sensitivity to detecting changes in the functional groups belonging to tissue components such as lipids, proteins and nucleic acids [2]. Infrared spectra of human and animal tissues could provide information on the molecular structure of tissues. FT-IR has been extensively applied for the determination of a biochemical metabolite in biological fluids. Diagnosis of various types of malignancies such as lung, breast, skin, cervical and colon cancers is already reported in the literature. The spectra are analysed for changes in levels of molecules such as RNA, DNA, phosphates, and carbohydrates. Variation of the RNA/DNA ratio as measured at 1121/1020 cm-1 generally show higher ratio for malignant tissues compared to their non-malignant counterpart. Changes in the spectra of malignant samples were also observed in the symmetric and asymmetric stretching bands of the phosphodiester backbones of nucleic acids, the CH stretching region, the C-O stretching bands of the C-OH groups of carbohydrates and cellular protein residuals, and the pressure dependence of the CH2 stretching mode [3]. The changes in the FTIR spectra correlate to modification of bases and sugars, and redistribution of the H-bond network. The loss/change in the covalent bonds due to damage in the primary, secondary and tertiary structure of nucleic acids can be observed in the spectra. These changes involved the phosphate and C-O stretching bands, the CH stretch region, and the pressure dependence of the CH2 bending and C=O stretching modes. FTIR micro spectroscopy has also been used as a fast diagnostic technique to identify drugs targeting specific molecular pathways causing chronic myeloid leukaemia. Chemometric data analysis was used to assess drug compounds in ex vivo cancer cells [4]. Substantial progress has been made in incorporating advances in computational methods into the system to increase the sensitivity of the entire setup, making it an objective and sensitive technique suitable for automation to suit the demands of the medical community. FTIR spectroscopy provides the possibility of obtaining information on molecular composition and structure at the level of single cell within a time-scale of few seconds-minutes and to perform qualitative and quantitative multi-component analyses. It helps in automated pattern recognition and objective classifications of samples with minimal and label-free sample treatment. The technical improvements will progressively increase the number of potential applications of micro FT-IR to cancer research and clinical diagnosis. It may be hoped that the future pre-clinical and clinical trials will include sample evaluation utilizing this technique in order to obtain data necessary to validate the use of micro FT-IR spectroscopy in a clinical context. In fact, this appears to be the most important way to reduce the high level of skepticism of many biologists and pathologists about an old technology that has been designed and improved mainly for applications in clinical diagnosis including cancer research.
关键词： cancer research,biomedicine,clinical diagnosis,Fourier transform infrared spectroscopy,FTIR,clinical research
更新于2025-09-09 09:28:46
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Chemometric Approaches for Developing Infrared Nanosensors to Image Anthracyclines
摘要： Generation, identification, and validation of optical probes to image molecular targets in a biological milieu remains a challenge. Synthetic molecular recognition approaches leveraging the intrinsic near-infrared fluorescence of single-walled carbon nanotubes is a promising approach for long-term biochemical imaging in tissues. However, generation of nanosensors for selective imaging of molecular targets requires a heuristic approach. Here, we present a chemometric platform for rapidly screening libraries of candidate single-walled carbon nanotube nanosensors against biochemical analytes to quantify fluorescence response to small molecules including vitamins, neurotransmitters, and chemotherapeutics. We further show this approach can be leveraged to identify biochemical analytes that selectively modulate the intrinsic near-infrared fluorescence of candidate nanosensors. Chemometric analysis thus enables identification of nanosensor-analyte ‘hits’ and also nanosensor fluorescence signaling modalities such as wavelength-shifts that are optimal for translation to biological imaging. Through this approach, we identify and characterize a nanosensor for the chemotherapeutic anthracycline doxorubicin, which provides an up to 17 nm fluorescence red-shift and exhibits an 8 μM limit of detection, compatible with peak circulatory concentrations of doxorubicin common in therapeutic administration. We demonstrate selectivity of this nanosensor over dacarbazine, a chemotherapeutic commonly co-injected with DOX. Lastly, we demonstrate nanosensor tissue compatibility for imaging of doxorubicin in muscle tissue by incorporating nanosensors into the mouse hindlimb and measuring nanosensor response to exogenous DOX administration. Our results motivate chemometric approaches to nanosensor discovery for chronic imaging of drug partitioning into tissues and towards real-time monitoring of drug accumulation.
关键词： fluorescence response,single-walled carbon nanotubes,infrared nanosensors,biological imaging,doxorubicin,chemometric approaches,anthracyclines
更新于2025-09-09 09:28:46
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“Guide Star” Assisted Noninvasive Photoacoustic Measurement of Glucose
摘要： A novel “guide star” assisted photoacoustic (GSPA) method for noninvasive glucose measurement has been proposed. Instead of receiving PA signals that are directly generated by tissue, a virtual photodiode is employed to amplify the PA signal difference regarding amplitude and peak arrival time caused by glucose concentration variations in an indirect way. Being different from traditional PA spectroscopy, this method can improve sensitivity and accuracy by optimizing optical path lengths (or tissue thickness). On the other hand, being superior to near-infrared (NIR) spectroscopy, it utilizes both optical absorption and acoustic propagation velocity information offered by PA signals. Theoretical analysis and simulation have been done to illustrate how the concentration change affects the PA waveform. In vitro experiments on aqueous glucose solution were conducted with concentrations varying in human physiological range (50~350 mg/dL). Performance of quartz cuvettes with 1-mm and 2-mm optical path lengths were compared in terms of correlation quality (R2), degree of agreement (Bland-Altman plot) and clinical accuracy (Clarke’s Error Grid analysis) to demonstrate the scalability of sensitivity provided by the indirect method. Longer optical length shows better sensitivity and accuracy in this case. Moreover, detection was also done on human blood serum to further prove the potential of the proposed method for clinical application. Our proposed method provides solution to enhance sensitivity, facilitating development of portable and low-cost PA sensors with low power laser diodes for noninvasive glucose monitoring and other applications.
关键词： near-infrared,photoacoustics,virtual photodiode,noninvasive glucose monitoring,Diabetes Mellitus
更新于2025-09-09 09:28:46
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Structural, Infrared, Magnetic, and Electrical Properties of Ni0.6Cd0.2Cu0.2Fe2O4 Ferrites Synthesized Using Sol-Gel Method Under Different Sintering Temperatures
摘要： Ni0.6Cd0.2Cu0.2Fe2O4 ferrites were synthesized using sol-gel method under different sintering temperatures. XRD patterns with the Rietveld refinement indicate that samples crystallize in the cubic spinel structure. The increase of sintering temperature leads successively to the increase of lattice constant, average crystallite size, intensities of absorption bands, magnetization, and electrical conductivity of the prepared ferrites. Dielectric constants decrease with frequency and their behaviors have been investigated using the interfacial polarization theory predicted by Maxwell. The modulus analysis shows the presence of electrical relaxation phenomenon and non-Debye nature for the samples. An appropriate electrical equivalent circuit was used to analyze the Nyquist plots, and the results show that the conduction mechanism of the synthesized ferrites is mainly due to the grain boundary contribution.
关键词： Ferrites,conductivity,Rietveld refinement,Sol-gel method,Infrared properties,Dielectric properties
更新于2025-09-09 09:28:46
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Effective detection by fusing visible and infrared images of targets for Unmanned Surface Vehicles
摘要： The research progress for Unmanned Surface Vehicle (USV) is of great significance to human off-shore operations. Target detection is the foundation for USV applications. Ocean wave, frog, and illumination are the most important factors that affect exactness of target detection through visible and infrared images. This paper proposes an algorithm for weighted averaging fusion of visible/infrared images. Firstly, the visible light/infrared devices are required to collect the target surrounding information, perform feature analysis, and complete the anti-fog and de-noising preprocessing. These operations aim at improving the accuracy of image segmentation. Secondly, feature extractions of the visible and infrared target images are performed, respectively, and the recognition of the target image is further completed. Finally, image fusion is performed by weighted averaging of the targets detected by visible light and infrared images. The fusion uses a matching matrix to represent the similarity of the two images. When the two images are very similar, the image is fused by weighting pixels, which effectively improves the accuracy of the detection. Lots of simulations were conducted on MATLAB 2015a with a personal computer, and the results verified the success rate of target detection and recognition.
关键词： fusion,Multi-scale fractal,target detection,visible image,infrared image
更新于2025-09-09 09:28:46
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aIR-Jumper: Covert Air-Gap Exfiltration/Infiltration via Security Cameras & Infrared (IR)
摘要： Breaching highly secure networks with advanced persistent threats (APTs) has been proven feasible in the last decade, however communication between the attacker outside the organization and the APT inside the organization is not possible if the compromised network is disconnected from the Internet. In this paper, we show how attackers can exploit surveillance cameras to establish covert communication between the air-gapped networks of organizations and remote attackers. We present bidirectional communication allowing inbound and outbound data transfer. Infiltration. An attacker standing in a public area (e.g., in the street) uses near infrared light (NIR) to transmit hidden signals to the surveillance camera(s). Such NIR signals at a wavelength of 800-900nm are invisible to humans, but cameras are optically sensitive to this type of light. Binary data is encoded and modulated on top of the IR signals. The signals hidden in the video stream are then intercepted and decoded by the malware residing in the internal network. Exfiltration. Surveillance and security cameras are equipped with controllable IR LEDs which are used for night vision. We show that the malware can control the strength of the IR illumination. Sensitive data such as PIN codes, passwords, and encryption keys are then modulated, encoded, and transmitted over the IR signals. An attacker in a public area (e.g., in the street) with a line of sight to the surveillance camera records the IR signals and decodes the leaked information. We discuss related work on air-gap covert channels and provide scientific background about our optical channel. Our evaluation shows that an attacker can establish bidirectional communication with the internal networks from distances of tens of meters to kilometers away via surveillance cameras and IR light.
关键词： surveillance cameras,infrared,Air-gap,data exfiltration,data infiltration,covert channel
更新于2025-09-09 09:28:46
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Sr2MgWO6:Cr3+ phosphors with effective near-infrared fluorescence and long-lasting phosphorescence
摘要： Cr3+-doped near-infrared (NIR) long-lasting phosphorescence (LLP) phosphors have drawn great attention for the promising application in unique bio-labels. Most of the studies are focused on gallate materials. Here we report a novel non-gallates NIR LLP phosphor Sr2MgWO6:Cr3+ that exhibit broadband emission at 700–1000 nm. X-ray powder diffraction, photoluminescence spectra, photoluminescence excitation spectra, LLP decay curves and thermoluminescence glow curves were determined to study the NIR LLP property and mechanism of Sr2MgWO6:Cr3+. Although Sr2MgWO6:0.4%Cr3+ gives the strongest NIR emission, the optimum content of Cr3+ in Sr2MgWO6 phosphor for LLP was 0.1%. Trap type and depth in Sr2MgWO6:Cr3+ were also discussed according to the thermoluminescence glow curves. Sr2MgWO6:Cr3+ phosphor is promising in optical information storage, night-vision surveillence, and in vivo bio-imaging.
关键词： long-lasting phosphorescence,Cr3+,Sr2MgWO6,near-infrared
更新于2025-09-09 09:28:46
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A novel near-infrared “turn-on” fluorescent probe for selective detection of Fe3+ and its application in vitro imaging
摘要： A novel near-infrared fluorescent probe RHCC was devised and synthesized. It exhibits high specificity to Fe3+ compared to other metals in aqueous solutions. The detection limit of RHCC was 1.2 × 10-7 M and the complexation stability constant was 5.807 × 104 M-1. The binding ratio of RHCC and Fe3+ was 1:1 which was measured through MS, FTIR and Job’s plot. The energy gap between HOMO and LUMO of RHCC was 3.22 eV, while RHCC-Fe3+ complex was 0.95 eV. This result means the binding of probe RHCC and Fe3+ lowers the RHCC-Fe3+ complex’s energy gap and makes it more stable. What’s more, in living cells and zebrafishes studies, probe RHCC was no significant cytotoxic effect, indicating it could monitor Fe3+ in biological system.
关键词： near-infrared probe,vitro imaging,“turn-on”,high specificity
更新于2025-09-09 09:28:46
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Ultrathin tungsten bronze nanowires with efficient photo-to-thermal conversion behavior
摘要： In this work, we describe a simple one-step solvothermal method to synthesize ultrathin quaternary tungsten bronze nanowires (QTBNWs). In addition, a series of alkali metal-doped QTBNWs can be prepared by simply changing the type of starting alkali carbonate and tungstate. The as-synthesized QTBNWs exhibits strong near-infrared (NIR) rays absorption, high visible light transmission and excellent photo-to-thermal conversion behavior, which are superior to those of tungsten bronze nanorods and ternary TBNWs. And its excellent photothermal performance should be attributed to great localized surface plasmon resonances (SPR).
关键词： solvothermal method,photo-to-thermal conversion,near-infrared absorption,ultrathin tungsten bronze nanowires,surface plasmon resonances
更新于2025-09-09 09:28:46