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New results on NIR emission in Li₃Ba₂La₃(WO${}_4{)}_8$:Nd${}^{3+}$ prepared by the SSR method are reported. Prepared sample is examined by XRD for crystal structure confirmation. This compound crystallizes into the monoclinic crystal system with space group C2/c (No.15) having lattice parameters $a=5.323\AA ,b=13.091\AA ,c=19.48$Å, $\beta =91.18^{\circ }$, and $Z=2$. The photoluminescence recorded with 588nm (⁴I${}_{9/2}{\to }^4$F${}_{5/2})$ excitation shows characteristic line emission in the NIR region, with the most intense emission at 1069nm (⁴F${}_{3/2}{\to }^4$I${}_{11/2}$). Concentration quenching was observed for Nd${}^{3+}$ contents exceeding 2 mol%. The calculated critical distance is 40.16 Å.

Identification of aerosol type and chemical composition may help to trace their origin and estimate their impact on land and people. Aerosols chemical composition, size distribution and particles shape, manifest themselves in their spectral scattering cross-section. In order to make a reliable identification, comprehensive spectral analysis of aerosol scattering should be carried out. Usually, spectral LIDAR measurements of aerosols are most efficiently performed using an Nd:YAG laser transmitter in the fundamental frequency and its 2^nd, 3^rd and 4^th harmonics. In this paper we describe automatic detection and identification of several aerosol types and size distributions, using a multi-spectral lidar system operating in the IR, NIR and UV spectral regions. The LIDAR transmitter is based on a single Nd:YAG laser. In addition to the 3^rd and 4^th harmonics in the UV, two optical parametric oscillator units produce the eye-safe 1.5 µm wavelength in the near IR and up to 40 separable spectral lines in the 8-11 µm IR. The combination of a wide spectral coverage required for backscattering analysis combined with fluorescence data, enable the generation of a large spectral data set for aerosols identification. Several natural and anthropogenic aerosol types were disseminated in controlled conditions, to test system capabilities. Reliable identification of transient and continuous phenomena demands fast and efficient control and detection algorithms. System performance, using the specially designed algorithms, is described below.

Results of a first investigations on luminescence in Nd${}^{3+}$ doped Sr₃Bi(PO₄)₃ are presented. Typical emission is in near infrared (NIR) region consisting of lines attributable to f–f transitions. The excitation also comes from f–f transitions involving higher energy levels, spanning a broad spectral range starting from near ultraviolet (nUV) running through NIR. As much as 5mol.% of Nd${}^{3+}$ could be doped before concentration quenching of luminescence set in. The quenching was attributed to energy transfer between Nd${}^{3+}$ ions taking place through a multipolar mechanism; the critical distance being 21.64Å. An easy synthesis method involving low-cost chemicals and favorable luminescence properties makes this phosphor a potential candidate for NIR applications.

Cr${}^{3+}$-doped zinc gallate (ZnGa₂O₄) near-infrared (NIR) phosphors were synthesized via a high temperature solid state method. The luminescence properties of the phosphors were studied systematically. A significant spectra overlap between the emission of ZnGa₂O₄ and the absorption of Cr${}^{3+}$ was observed and 300 nm excitation exhibited the most excellent long-lasting luminescence properties among the three main excitation bands. Luminescence intensity was changed with the ratio of Ga${}^{3+}$/Cr${}^{3+}$ and the blue host emission of ZnGa₂O₄ was suppressed when doping Cr${}^{3+}$ into ZnGa₂O₄. The fluorescence decay curves of blue emission of ZnGa₂O₄ with different Cr${}^{3+}$ doping concentrations indicated that the lifetime of ZnGa₂O₄ at 505 nm become shorter with the increase of the Cr${}^{3+}$ concentration. Herein, a possible mechanism of long-lasting luminescence in ZnGa₂O₄: Cr${}^{3+}$ was proposed that the NIR long-lasting luminescence in ZnGa₂O₄: Cr${}^{3+}$ comes from the persistent energy transfer from ZnGa₂O₄ to Cr${}^{3+}$.

It is hard to achieve low bit error rate (BER) and high-quality signals in free-space optical (FSO) communication systems due to atmospheric link interference. For the sake of seeking solutions, we proposed an experimental scheme of free-space laser communication based on middle-wave infrared (MWIR) and near infrared (NIR) for obtaining atmospheric transmission characteristic in 1 km turbulence path. Compared with NIR waveband, MWIR-based scheme is more suitable for atmospheric FSO communication since it owns higher anti-interference ability for atmospheric attenuation, turbulence and skylight background noise. The experimental results may offer a significant reference for FSO communication in atmosphere link.

Near-infrared light-induced phototherapy including photothermal therapy (PTT) and photodynamic therapy (PDT) has emerged as a new noninvasive method for cancer treatment owing to the nature of high efficiency and spatiotemporal selectivity. In this study, a new boron-dipyrromethene (BODIPY) molecule (BDP-BT) with donor (D)-receptor (A)-donor (D) structure was designed and successfully synthesized by conjugation of benzothiadiazole (BT) with BODIPY structure. The polyethylene glycol chain (PEG) was modified onto the meso site of BODIPY to improve the hydrophilicity and biocompatibility of the compound. The amphiphilic BDP-BT was then self-assembled into nanoparticles (BDP-BT NPs) with red-shifted absorption and enhanced hydrophilicity. BDP-BT NPs can produce effective reactive oxygen species and local hyperthermia triggered by a single laser. The in vitro experiments revealed that BDP-BT NPs had good biocompatibility and remarkable photocytoxicity. The half maximal inhibitory concentration (IC${}_{50})$ of BDP-BT NPs was valued at 22.17 $\mu$g/mL under 635 nm laser irradiation. Furthermore, BDP-BT NPs can efficiently generate reactive oxygen species (ROS) in the tumor cells under light irradiation. Thus, the as-prepared BDP-BT NPs could be used as promising agents for PDT and PTT synergistic cancer therapy.

This paper reviews the history of the optoelectric devices applied to biomedical sciences in 20th century. It describes history of Vacuum tubes and Spectroscopies with the author's personal experiences, especially doublebeam spectroscopy. Further, the present developments of Near Infra Red (NIR) devices are described in translational biomedical applications. It includes particulary micro optoelectronics developments and present status of NIR breast cancer detection. Lastly, intrinsic molecular biomarkers are discussed especially NIR measurements of angiogenensis, hypermetabolism and heat production for cancer detection.

We utilized Near-Infrared (NIR) spectroscopy to closely investigate the activation change in anterior prefrontal cortex (aPFC) during verbal anagram problem-solving and learning. We used a parametric design of anagram-solving with three difficulty levels and evaluated anagram skill with two sets of subjects and protocols. The first protocol was a one-time evaluation of untrained subjects (n = 10) and the second protocol evaluated subjects over 6 weeks of training (n = 6). The untrained subjects in the first protocol demonstrated blood oxygenation corresponding to neuronal activation in the aPFC in response to medium and hard difficulty levels of the stimuli, while the easy anagram task deoxygenated the aPFC bilaterally, corresponding to deactivation. Higher performers have more aPFC activation than lower performers in the medium difficulty level anagram-solving task. Six weeks of training in the second protocol showed that training reduced oxygenation in aPFC. In particular, subjects with lower baseline skill in anagram production showed a larger reduction in oxygenation where true performance gains occurred (medium difficulty) and smaller reduction where the performance gains were limited (hard anagrams).

Association of the aPFC activation with the difficulty of the complex task suggests that aPFC is a part of a circuit for execution of task performance. In addition, more use of aPFC by untrained high performers suggests that the role of the aPFC is to increase efficiency of a problem-solving task. Thus, the NIR spectroscopy showed that the aPFC is a key structure in the circuit implementing the development of anagram skill.

Moisture content is an important trait for rubber sheet trading system. Therefore, a calibration equation for predicting moisture content was created by near infrared (NIR) technique in order to develop a more fair trading system in Thailand. Spectra were recorded in two systems. One was measurement on each rubber sheet and the other was on a pile of sheets. Both were measured by a handheld NIR spectrometer in the short wavelength region (700–1100 nm) in the transflectance mode using Teflon as a diffuse reflector. The spectra showed the peak at about 900 nm which belongs to isoprene, the major component of rubber sheet. Pretreatment with second derivative was applied to remove baseline shift effect occurring due to thickness differences on each rubber sheet. From validation results, moisture contents predicted by single sheet system were more accurate than a pile of sheet system with standard error of prediction (SEP) = 0.39% and bias of -0.07%, and they were not significantly different from the actual values at 95% confidence. As a result, determining moisture content in each rubber sheet by a handheld NIR spectrometer provided accurate values, easy and rapid operation.

Watercore and sugar content are internal qualities which are impossible for exterior determination. Therefore the aims of this study were to develop models for nondestructive detection of watercore and predicting sugar content in pear using Near Infrared Spectroscopy (NIR) technique. A total of 93 samples of Asian pear variety "SH-078" were used. For sugar content, spectrum of each fruit was measured in the short wavelength region (700–1100 nm) in the reflection mode and the first derivative of spectra were then correlated with the sugar content in juice determined by digital refractometer. Prediction equation was performed by multiple linear regression. The result showed Standard Error of Prediction (SEP) = 0.58°Bx, and Bias=0.11. The result from t-test showed that sugar content predicted by NIR was not significantly different from the value analyzed by refractometer at 95% confidence. For watercore disorder, NIR measurement was performed over the short wavelength range (700–850 nm) in the transmission mode. The first derivative spectra were correlated with internal qualities. Then principle component analysis (PCA) and partial least squares discriminant analysis (PLSDA) were used to perform discrimination models. The accuracy of the PCA model was greater than the PLSDA one. The scores from PC1 were separated into two boundaries, one predicted rejected pears with 100% classification accuracy, and the other was accepted pears with 92% accuracy. The high accuracy of sugar content determining and watercore detecting by NIR reveal the high efficiency of NIR technique for detecting other internal qualities of fruit in the future.

Insect infestation in rice stock is a significant issue in rice exporting business, resulting in the loss of product quality, nutrient as well as the economic losses. However, detecting the insect contamination with the traditional sorting techniques were destructive, inaccurate, time consuming and unable to detect the internal insect infestation. This study used near infrared (NIR) spectroscopy for obtaining the absorbent spectra from the insect contamination in two kinds of rice samples, Milled Hommali rice (MHR) and Brown Hommali rice (BHR). The mathematical methods of partial least squares (PLSs) regression and singular value decomposition (SVD) were employed to construct the predicting model. The statistical analysis results, R², RMSEP, RPD and bias, concluded that the predictive models from PLS for MHR and BHR were 0.95 and 0.90, 0.014 and 0.019, 4.79 and 3.11, as well as $-$0.007 and −0.008, respectively; while the statistical analysis results from SVD for MHR and BHR were 0.97 and 0.96, 0.012 and 0.013, 5.71 and 5.39, as well as $-$0.003 and 0.002, respectively. It showed that SVD technique performed better than PLS technique which shows that using the advantage of SVD technique required less amounts of wave numbers for predicting and was possible to construct the low cost handheld equipment for detecting the insects in rice samples.

Diabetes mellitus is a metabolic disorder that affects the production or usage of insulin by the body. Diabetes prevails in the body as a long-term condition which causes several other disorders if left unnoticed. Proper control of Diabetes needs continuous monitoring. The current measurement technique is invasive in nature and requires the withdrawal of blood from the body. Periodic quantification of blood glucose leads to pain and discomfort for the subject. This paper presents a non-invasive glucose measuring system using near-infrared diffuse reflectance spectroscopy (DRS). This work attempts to determine the blood glucose value from the diffuse reflected spectra in the NIR region. The study is executed with the spectral signatures of 33 diabetic subjects collected non-invasively using diffuse reflectance spectrometer from a diabetic centre. Blood glucose level of the same subjects are also recorded using the clinical method. The spectral information is subjected to standard normal variate (SNV) preprocessing method to remove baseline drift and then dimension reduction using singular value decomposition (SVD) is applied to the preprocessed data. The extracted singular values when compared with the clinically measured blood glucose is found to have a proportional relationship. The proposed study using singular value decomposition paves us the way for estimating the blood glucose value non-invasively with the obtained set of clinical blood glucose and the corresponding singular value table as a standard reference set.

Identification of aerosol type and chemical composition may help to trace their origin and estimate their impact on land and people. Aerosols chemical composition, size distribution and particles shape, manifest themselves in their spectral scattering cross-section. In order to make a reliable identification, comprehensive spectral analysis of aerosol scattering should be carried out. Usually, spectral LIDAR measurements of aerosols are most efficiently performed using an Nd:YAG laser transmitter in the fundamental frequency and its 2^nd, 3^rd and 4^th harmonics. In this paper we describe automatic detection and identification of several aerosol types and size distributions, using a multispectral lidar system operating in the IR, NIR and UV spectral regions. The LIDAR transmitter is based on a single Nd:YAG laser. In addition to the 3^rd and 4^th harmonics in the UV, two optical parametric oscillator units produce the eye-safe 1.5 μm wavelength in the near IR and up to 40 separable spectral lines in the 8-11 μm IR. The combination of a wide spectral coverage required for backscattering analysis combined with fluorescence data, enable the generation of a large spectral data set for aerosols identification. Several natural and anthropogenic aerosol types were disseminated in controlled conditions, to test system capabilities. Reliable identification of transient and continuous phenomena demands fast and efficient control and detection algorithms. System performance, using the specially designed algorithms, is described below.

Micro-opto-electro-mechanical systems (MOEMS) have been used to miniaturize traditional spectrometers successfully in the last decades. This paper present the optical system and realization strategy of a spectrometer based on torsional MOEMS scanning grating. The introduction of achromatic doublet in a modified Czerny-Turner optical layout enables the design of micro spectrometers capable of acquiring better effect of collimation and couple from light source. The research laid the foundation of optical design and serves for the further development.