Near‐Infrared Light‐Triggered Dual Drug Release Using Gold Nanorod‐Embedded Thermosensitive Nanogel‐Crosslinked Hydrogels

Gold nanorod (AuNR)‐embedded poly(N‐isopropylacrylamide) (PNIPAM) hydrogels offer the possibility of achieving near‐infrared (NIR) light‐triggered drug release. In addition, using nanoparticles as a crosslinker can enhance the mechanical properties of PNIPAM hydrogels, and nanoparticle‐crosslinked hydrogels provide an important approach for dual drug release. Here, NIR light‐triggered dual drug release using AuNR‐embedded thermosensitive nanogel‐crosslinked hydrogels is reported for the first time. Two kinds of drugs are encapsulated, one in the nanogel and the other in the hydrogel. The volume phase transition of the PNIPAM hydrogels is induced by NIR light by utilizing the photothermal effect of AuNRs. By changing the number of embedded AuNRs and the intensity of NIR light, the release rate and drug quantity can be adjusted for on‐demand release. Because of its NIR light‐triggering and nanoparticle‐crosslinking capabilities, AuNR‐embedded thermosensitive nanogel‐crosslinked hydrogels may expand the application scope of hydrogels and provide enhanced properties in their applications.     

Near‐Infrared Light Triggered Soft Actuators in Aqueous Media Prepared from Shape‐Memory Polymer Composites

Light triggered soft actuator in aqueous media has applications in operating underwater objects, creating liquid flow, and adjusting reaction velocity, etc. Here, composites prepared from commercial materials, poly[ethylene‐ran‐(vinyl acetate)] (EVA) and aniline black (AB), are reported as one cost efficient material for preparing such actuator, where EVA and AB work respectively as shape‐memory polymer matrix and near‐infrared light triggered photothermal filler. Upon irradiation, the temperature of the composites increases greatly with light power density and AB content. Light‐induced shape‐memory effect (SME) with recovery ratio >98%, temperature‐memory effect (TME), and reversible bidirectional shape‐memory effect (rbSME) of the prepared composites in air are realized. Higher light power density is required to trigger the shape recovery in aqueous media, while good SME, TME, and rbSME are also achieved. Releasing device and gripper are used to indicate the feasibility of the composites as light triggered soft underwater actuators.

     

Theranostic Polyaminocarboxylate–Cyanine–Transferrin Conjugate for Anticancer Therapy and Near‐Infrared Optical Imaging

Iron chelation therapy has been recognized as a promising antitumor therapeutic strategy. Herein we report a novel theranostic agent for targeted iron chelation therapy and near‐infrared (NIR) optical imaging of cancers. The theranostic agent was prepared by incorporation of a polyaminocarboxylate‐based cytotoxic chelating agent (N‐NE3TA; 7‐[2‐[(carboxymethyl)amino]ethyl]‐1,4,7‐triazacyclononane‐1,4‐diacetic acid) and a NIR fluorescent cyanine dye (Cy5.5) onto a tumor‐targeting transferrin (Tf). The N‐NE3TA–Tf conjugate (without Cy5.5) was characterized and evaluated for antiproliferative activity in HeLa, HT29, and PC3 cancer cells, which have elevated expression levels of the transferrin receptor (TfR). The N‐NE3TA–Tf conjugate displayed significant inhibitory activity against all three cancer cell lines. The NIR dye Cy5.5 was then incorporated into N‐NE3TA–Tf, and the resulting cytotoxic and fluorescent transferrin conjugate N‐NE3TA–Tf–Cy5.5 was shown by microscopy to enter TfR‐overexpressing cancer cells. This theranostic conjugate has potential application for dual use in targeted iron chelation cancer therapy and NIR fluorescence imaging.     

Near‐infrared spectra of polyamide 6, poly(vinyl chloride), and polychlorotrifluoroethylene

The near‐infrared spectra (NIR) of polyamide 6 (PA 6), poly(vinyl chloride) (PVC), and polychlorotrifluoroethylene (PCTFE) were measured. The tentative assignment of the overtone and combination frequencies was made with curve fitting calculations and local mode theory. Anharmonicity correction and mechanical frequency were determined from a Birge–Sponer plot. Tentative assignments of stretch overtone frequencies of CH₂, NH, and CO functional groups of PA 6 and CH₂, and CH functional groups of PVC were made. Anharmonicity corrections of 55, 61, and 20 cm^?1 were obtained for CH₂, NH, and CO stretch modes of PA 6, respectively, and of 60 and 66 cm^?1 for CH₂ and CH stretch modes of PVC, respectively. The local mode model seems to be adequate to interpret the origin of the bands observed in NIR spectra of PA 6 and PVC. Anharmonicity corrections of 33, 19, and 16 cm^?1 were obtained, respectively, for CF, asymmetrical CF₂, and symmetrical CF₂ stretch of PCTFE functional groups. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 199–208, 2002     

Temporal Aggregation of Seasonally Near‐Integrated Processes

We investigate the implications that temporally aggregating, either by average sampling or systematic (skip) sampling, a seasonal process has on the integration properties of the resulting series at both the zero and seasonal frequencies. Our results extend the existing literature in three ways. First, they demonstrate the implications of temporal aggregation for a general seasonally integrated process with S seasons. Second, rather than only considering the aggregation of seasonal processes with exact unit roots at some or all of the zero and seasonal frequencies, we consider the case where these roots are local‐to‐unity such that the original series is near‐integrated at some or all of the zero and seasonal frequencies. These results show, among other things, that systematic sampling, although not average sampling, can impact on the non‐seasonal unit root properties of the data; for example, even where an exact zero frequency unit root holds in the original data it need not necessarily hold in the systematically sampled data. Moreover, the systematically sampled data could be near‐integrated at the zero frequency even where the original data is not. Third, the implications of aggregation on the deterministic kernel of the series are explored.‐142     

Extreme Spectra of Var Models and Orders of Near‐Cointegration

Abstract. In this paper, we study the spectral properties of a bivariate vector autoregressive VAR(p) model when a root z₀ = ρ₀e^iλ0 of the determinant of the model's characteristic matrix Φ(z) approaches the unit circle, the border of non‐stationarity. Let Φ_xx(z), Φ_xy(z), Φ_yx(z), Φ_yy(z) be the polynomial elements of Φ(z). We show that, depending on the relation of the order of z₀ as root of det(Φ(z)) with the orders of z₀ as root of Φ_ij(z), (i,j ∈ {x,y}), the two marginal spectra may tend to infinity at λ₀, while the coherence may tend to unity at λ₀. We investigate the conditions under which any of the above will occur, in detail. In the specific case where z₀→1, the marginal series will be near‐integrated of certain orders of near‐integration, while there will eventually exist a linear combination of them with a lower order of near‐integration. We study the possible combinations of their orders of near‐integration. Finally, we develop a strategy with the help of which one may define a VAR(p) model with pre‐specified extreme spectral features and give some examples. Beyond the benefits of this latter for VAR model simulation, the analysis has, moreover, implications concerning the adequacy of VAR model fitting.     

Spectroscopic Investigations of High‐Nitrogen Compounds for Near‐Infrared Illuminants

Alkaline metal salts are widely used in pyrotechnic formulations. For NIR pyrotechnics, potassium, and cesium nitrate are mainly used as oxidizers and infrared emitters. Herein, new NIR illuminant formulations were tested using several potassium and cesium salts of high‐nitrogen compounds such as tetrazole and triazole derivatives. The research of new formulations comprises the evaluation of sensitivity data and radiometric measurements of new formulations. It was further investigated whether the IR emission can be improved using different nitrogen releasing agents like aminotetrazole or diethylene triamine trinitrate (DETT) as hexamethylenetetramine replacements.     

Nondestructive Estimation of Fat Constituents of Sesame (Sesamum indicum L.) Seeds by Near‐Infrared Reflectance Spectroscopy

A rapid and efficient method for oil constituent estimation in intact sesame seeds was developed through near‐infrared reflectance spectroscopy (NIRS) and was used to evaluate a sesame germplasm collection conserved in China. A total of 342 samples were scanned by reflectance NIR in a range of 950–1650 nm, and the reference values for oil content and fatty acid (FA) profiles were measured by Soxhlet and gas chromatograph methods. Useful chemometric models were developed using partial least squares regression with full cross‐validation. The equations had low standard errors of cross‐validation, and high coefficient of determination of cross‐validation (R_c²) values (>0.8) except for stearic acid (0.794). In external validation, r² values of oil and FA composition equations ranged from 0.815 (arachidonic acid) to 0.877 (linoleic acid). The relative predictive determinant (RPD_v) values for all equations were more than 2.0. The whole‐seed NIR spectroscopy equations for oil content and FA profiles can be used for sesame seed quality rapid evaluation. The background information of the 4399 germplasm resources and accessions with high linoleic acid content identified in this study should be useful for developing new sesame cultivars with desirable FA compositions in future breeding programs.     

Energy‐Transfer Modulation for Enhanced Photocatalytic Activity of Near‐Infrared Upconversion Photocatalyst

One of the major challenges of near‐infrared upconversion photocatalyst concerns strengthening the cooperation between Rare‐earth (RE) ions and semiconductor materials for enhancing NIR photocatalytic activity. Herein, the basic energy‐transfer (ET) process between RE ions and semiconductor materials is discussed and the appropriate mode, nonradiative ET, is proposed for efficiently coupling them. As an example, a novel NIR‐based UC photocatalyst, CaIn₂O₄:Yb³⁺,Tb³⁺ was designed and successfully fabricated, which exhibited high photocatalytic activity under 980 nm irradiation. The present report highlights the potential of ET tuning between RE ions and semiconductors toward high performance of NIR photocatalysis.     

In‐Line Monitoring and Control of Conversion and Weight‐Average Molecular Weight of Polyurethanes in Solution Step‐Growth Polymerization Based on Near Infrared Spectroscopy and Torquemetry

Summary: It is well known that the weight‐average molecular weight ( ) is strictly dependent on conversion in step‐growth polymerizations performed in batch and that the is very sensitive to impurities and molar imbalance. This makes the work of controlling a non trivial job. In this paper a new methodology is introduced for in‐line monitoring and control of conversion and of polyurethanes produced in solution step‐growth polymerizations, based on near‐infrared spectroscopy (NIRS) and torquemetry. A calibration model based on the PLS method is obtained and validated for monomer conversion, while the weight‐average molecular weight is monitored indirectly with the relative shear signal provided by the agitator. Control procedures are then proposed and implemented experimentally to avoid gelation and allow for maximization of . The proposed monitoring and control procedures can also be applied to other step growth polymerizations.

Proposed control scheme.     

基于红外热成像技术的电气设备预知维护专家系统

介绍了一种以红外热成像技术为基础的电气设备预知维护专家系统的应用设计方案,对电气设备运行维护的现状、预知维护的概念和红外热成像技术进行了简要分析,详细说明了预知维护专家系统的构成、开发过程和实际应用作,重点阐述了如何利用红外热成像技术,建立状态分析专家系统,实现电气设备的预知维护.     

A Soft Chemistry‐Based Route to Near‐Infrared Luminescent Bismuth‐Activated Glass Films

Near‐infrared (NIR) luminescent materials activated by bismuth are of fundamental and technological importance because of a broad diversity of high‐value applications for optical telecommunications and biomedicine. The preparation of Bi‐activated films commonly relies on the physical vapor deposition technique including cosputtering and pulse laser deposition. Such conventional methods consist of the preparation of targets, exploring various preparation parameters using expensive experimental apparatuses, and in situ or postthermal treatment of the as‐prepared films. Here, we report on a soft chemistry‐based approach for the fabrication of NIR luminescent bismuth‐activated glass films. The resulting films demonstrate ultrabroad, long‐lived photoluminescence in the range 950–1500 nm. This approach is very flexible, permitting the selection of unusual combinations of active centers to tailor functionality. This strategy greatly enriches the techniques for the preparation of bismuth‐activated films, providing great promise for the realization of waveguide‐type optical amplifiers and lasers.     

Chemiluminescence of isotactic polypropylene induced by photo‐oxidative degradation and natural weathering

The analysis of the chemiluminescence (CL) kinetic parameters (induction time, oxidation rate, and activation energy) after the UV irradiation and outdoor exposure of isotactic polypropylene (i‐PP) films have been studied. The initial CL emission intensity increased with increasing photodegradation time of i‐PP films. On photodegradation, the activation energies were found to decrease linearly with time of UV‐irradiation and outdoor exposure. The slopes of these linear dependences were used to indicate the degree of photodegradation of the polymer and also for the characterization of the stabilizing effect of the additive. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4623–4629, 2006     

Intraoperative Tumor Detection Using Pafolacianine

Cancer is a leading cause of death worldwide, with increasing numbers of new cases each year. For the vast majority of cancer patients, surgery is the most effective procedure for the complete removal of the malignant tissue. However, relapse due to the incomplete resection of the tumor occurs very often, as the surgeon must rely primarily on visual and tactile feedback. Intraoperative near-infrared imaging with pafolacianine is a newly developed technology designed for cancer detection during surgery, which has been proven to show excellent results in terms of safety and efficacy. Therefore, pafolacianine was approved by the U.S. Food and Drug Administration (FDA) on 29 November 2021, as an additional approach that can be used to identify malignant lesions and to ensure the total resection of the tumors in ovarian cancer patients. Currently, various studies have demonstrated the positive effects of pafolacianine’s use in a wide variety of other malignancies, with promising results expected in further research. This review focuses on the applications of the FDA-approved pafolacianine for the accurate intraoperative detection of malignant tissues. The cancer-targeting fluorescent ligands can shift the paradigm of surgical oncology by enabling the visualization of cancer lesions that are difficult to detect by inspection or palpation. The enhanced detection and removal of hard-to-detect cancer tissues during surgery will lead to remarkable outcomes for cancer patients and society, specifically by decreasing the cancer relapse rate, increasing the life expectancy and quality of life, and decreasing future rates of hospitalization, interventions, and costs.     

基于显微红外成像技术的碱处理丝瓜络纤维的研究

为了更好地研究碱处理浓度对丝瓜络成分的影响,采用显微红外成像技术对不同浓度碱处理后的丝瓜络进行表征。研究结果表明,碱处理可有效去除丝瓜络中的半纤维素,从而使纤维素含量增加。碱处理2 h条件下,5%的碱溶液即可去除丝瓜络中绝大部分的半纤维素,对于木质素去除也有一定效果;继续提高碱处理浓度并不会进一步降低半纤维素含量,且对木质素去除也没有明显效果,木质素相对含量反而有所上升。与传统的红外光谱法相比,采用显微红外成像技术可研究不同碱处理后丝瓜络中的半纤维素、木质素和纤维素在各扫描微区的组分分布情况,使丝瓜络纤维在碱处理前后形貌及其含量分析表达更加直观,具有图谱合一、可视性、高灵敏度等优点。     

显微红外成像和衰减全反射技术在不同种属黄精中的鉴别研究

探讨了显微成像和衰减全反射两种红外模式对不同种属黄精的鉴别.以6种不同种属的黄精样品为研究对象,一份样品经冰冻切片机进行取样,采用显微红外仪器进行扫描;另一份样品经烘干打粉,采用衰减全反射模式扫描.结果表明,以多糖含量高低作为鉴别依据,衰减全反射模式可以快速判别出是否含有多糖以及简单比较不同种属黄精间含量差异,而显微红...     

Near‐Infrared Broadband Photoluminescence of Bismuth‐Doped Zeolite‐Derived Silica Glass Prepared by SPS

Through the order–disorder transition process of zeolites, bismuth‐doped zeolite‐derived silica glasses with broadband near‐infrared (NIR) photoluminescence have been successfully prepared by spark plasma sintering (SPS). The samples were characterized by X‐ray diffraction, UV‐vis, photoluminescence, and fluorescence lifetime. The results showed that as‐prepared samples possessed favorable broadband NIR luminescence. The NIR emission (peaked at ~1140 nm) intensity decreased with increasing the bismuth doping concentration when excited by 500 and 700 nm. The tendency was different from the emissions (peaked at ~1240 nm) excited by 800 nm. In addition, the NIR fluorescence peaks of the fixed Bi concentration sample can be observed almost around 1140 or 1240 nm when excited by different wavelengths from 500 to 950 nm. These phenomena implied that the NIR emission peaked at different wavelengths may originate from different bismuth species. Three kinds of Bi active centers Bi⁺, Bi⁰, and (Bi₂)^2? were proposed to contribute to the NIR emission peaks at ~1140, 1240, and 1440 nm, respectively. Interestingly, a broadband NIR emission peaked at 1207 nm with a full‐width at half maximum of 273 nm was observed when excited by 600 nm, whose intensity was stronger than that excited by 800 nm. This property might be useful for broadband fiber amplifiers and tunable lasers.     

Near‐Infrared and Visible Absorption Spectroscopy of Nano‐Energetic Materials Containing Aluminum and Boron

Near‐infrared and visible absorption spectra are measured for nano‐energetic materials consisting of thirteen different types of Al or B nano‐particles in the 30 nm to 1 μm size range embedded in nitrocellulose or Teflon oxidizers, using an integrating sphere absorption spectrometer. The Al nano‐particle absorption is generally similar to the spectra of bulk Al, but the absorption strength is size‐dependent and up to twelve times more intense. Absorption coefficients are determined as a function of nano‐particle loading. For Al particles where the size is known, per particle cross sections are also determined. The ratio of cross section to volume decreases with increasing particle size. The implications of these measurements for nano‐sized energetic material analysis and for laser‐ignition experiments are briefly discussed.