Near-infrared Spectral Measurements Research Articles

Near Infrared Spectroscopy Enables Differentiation of Mechanically and Enzymatically Induced Cartilage Injuries

This study evaluates the feasibility of near infrared (NIR) spectroscopy to distinguish between different cartilage injury types associated with post-traumatic osteoarthritis and idiopathic osteoarthritis (OA) induced by mechanical and enzymatic damages. Bovine osteochondral samples (n = 72) were subjected to mechanical (n = 24) and enzymatic (n = 36) damage; NIR spectral measurements were acquired from each sample before and after damage, and from a separate control group (n = 12). Biomechanical measurements were then conducted to determine the functional integrity of the samples. NIR spectral variations resulting from different damage types were investigated and the samples classified using partial least squares discriminant analysis (PLS-DA). Partial least squares regression (PLSR) was then employed to investigate the relationship between the NIR spectra and biomechanical properties of the samples. Results of the study demonstrate that substantial spectral changes occur in the region of 1700–2200 nm due to tissue damages, while differences between enzymatically and mechanically induced damages can be observed mainly in the region of 1780–1810 nm. We conclude that NIR spectroscopy, combined with multivariate analysis, is capable of discriminating between cartilage injuries that mimic idiopathic OA and traumatic injuries based on specific spectral features. This information could be useful in determining the optimal treatment strategy during cartilage repair in arthroscopy.

Developing and Implementing an R Shiny Application to Introduce Multivariate Calibration to Advanced Undergraduate Students

During a short chemometrics course in the seventh semester of the chemistry undergraduate program, students receive a brief theoretical introduction to multivariate calibration, focused on partial least-squares regression as the most commonly employed data processing tool. The theory is complemented with the use of MVC1_R, an easy-to-use software developed in-house as an R Shiny application. The present report describes student activities with the latter software in the development of mathematical models to predict quality parameters of corn seeds from near-infrared spectra. Subsequently, an experimental project is carried out involving near-infrared spectral measurements, which are widely used in several industrial fields for quality control. To process the obtained data, students apply the knowledge acquired during the theoretical/software sessions.

Effect of the Architecture of Fiber-Optic Probes Designed for Soluble Solid Content Prediction in Intact Sugar Beet Slices.

Sugar beet is the second biggest world contributor to sugar production and the only one grown in Europe. One of the main limitations for its competitiveness is the lack of effective tools for assessing sugar content in unprocessed sugar beet roots, especially in breeding programs. In this context, a dedicated near infrared (NIR) fiber-optic probe based approach is proposed. NIR technology is widely used for the estimation of sugar content in vegetable products, while optic fibers allow a wide choice of technical properties and configurations. The objective of this research was to study the best architecture through different technical choices for the estimation of sugar content in intact sugar beet roots. NIR spectral measurements were taken on unprocessed sugar beet samples using two types of geometries, single and multiple fiber-probes. Sugar content estimates were more accurate when using multiple fiber-probes (up to R2 = 0.93) due to a lesser disruption of light specular reflection. In turn, on this configuration, the best estimations were observed for the smallest distances between emitting and collecting fibers, reducing the proportion of multiply scattered light in the spectra. Error of prediction (RPD) values of 3.95, 3.27 and 3.09 were obtained for distances between emitting and collecting fibers of 0.6, 1.2 and 1.8 µm respectively. These high RPD values highlight the good predictions capacities of the multi-fiber probes. Finally, this study contributes to a better understanding of the effects of the technical properties of optical fiber-probes on the quality of spectral models. In addition, and beyond this specificity related to sugar beet, these findings could be extended to other turbid media for quantitative optical spectroscopy and eventually to validate considered fiber-optic probe design obtained in this experimental study.

Development and validation of in-line near-infrared spectroscopy based analytical method for commercial production of a botanical drug product

Near-infrared (NIR) spectroscopy is one of the most successful pharmaceutical process analytical tools. For botanical drug products (BDPs), many studies have applied NIR spectroscopy for rapid analysis of botanical raw materials, extracts and formulations. However, the real-time process analysis reported for BDPs was still mainly conducted on lab- or pilot- scale equipment, where some essential conditions of the materials and process parameters can be easily controlled for NIR spectral measurement. Due to the chemical and physical characteristics of the commercial production of BDPs, it is challenging to develop in-line NIR methods with enough robustness for industrial-scale application. This is the first reported case study of the development and validation of the in-line NIR method for the commercial production of BDPs, taking Compound Danshen Dripping Pill (CDDP) as an example. An in-line NIR method was developed for simultaneous measurement of the three critical quality attributes, i.e. the relative density, the moisture content and the content of 3,4-dihydroxyphenyl lactic acid (danshensu, a key active compound), during the extract concentration process. The NIR spectra and sample collection lasted for three years (67 production batches) to cover the variability of raw materials and process conditions. NIR calibration models were established respectively, with determination coefficients (r2) of 0.9905, root mean square errors of prediction (RMSEP) of 0.004 for the relative density in the range of 1.042–1.184; r2 of 0.9870, RMSEP of 1.1% for the moisture content in the range of 50.8–83.0%; r2 of 0.9870, RMSEP of 0.461 mg/g for danshensu in the range of 2.563–8.869 mg/g. Then, all the method validation parameters (accuracy, precision, range, specificity, linearity, robustness, detection and quantitation limits) were discussed according to the characteristics of the commercial production of BDPs. The NIR method development and validation strategy proposed may also be applied in the future for the commercial production of other BDPs.

Application of OPT101 sensor in ICU-specific near-infrared spectroscopy instrumentation

The OPT101 photoelectric sensor has the characteristics of good photoelectric response, built-in transimpedance amplifier and small size, which meet the needs of accurately near-infrared spectral measurement in medical near-infrared spectroscopy (NIRS) range. Our research team has developed a series of portable NIRS instruments for NIRS measuring in intensive care units (ICU). The characteristics and advantages of OPT101 in the development of clinical ICU-specific NIRS instruments were introduced. The research progress of our team on the development of ICU-NIRS instruments using OPT101 was reviewed. The prospect of OPT101 in clinical noninvasive detection was discussed. Key words: Optoelectronic sensor; Near-infrared spectroscopy; Thrombus diagnosis; Shock monitoring; Fatigue evaluation

Improving the spectral measurement accuracy based on temperature distribution and spectra-temperature relationship

Temperature is usually considered as a fluctuation in near-infrared spectral measurement. Chemometric methods were extensively studied to correct the effect of temperature variations. However, temperature can be considered as a constructive parameter that provides detailed chemical information when systematically changed during the measurement. Our group has researched the relationship between temperature-induced spectral variation (TSVC) and normalized squared temperature. In this study, we focused on the influence of temperature distribution in calibration set. Multi-temperature calibration set selection (MTCS) method was proposed to improve the prediction accuracy by considering the temperature distribution of calibration samples. Furthermore, double-temperature calibration set selection (DTCS) method was proposed based on MTCS method and the relationship between TSVC and normalized squared temperature. We compare the prediction performance of PLS models based on random sampling method and proposed methods. The results from experimental studies showed that the prediction performance was improved by using proposed methods. Therefore, MTCS method and DTCS method will be the alternative methods to improve prediction accuracy in near-infrared spectral measurement.

Near-infrared spectral measurements and multivariate analysis for predicting glass contamination of refuse-derived fuel

This paper investigates how glass contamination in refuse-derived fuel can be quantitatively detected using near-infrared spectroscopy. Near-infrared spectral data of glass in four different background materials were collected, each material chosen to represent a main component in municipal solid waste; actual refuse-derived fuel was not tested. The resulting spectra were pre-processed and used to develop multi-variate predictive models using partial least squares regression. It was shown that predictive models for coloured glass content are reasonably accurate, while models for mixed glass or clear glass content are not; the validated model for coloured glass content had a coefficient of determination of 0.83 between the predicted and reference data, and a root-mean-square error of validation of 0.64. The methods investigated in this paper show potential in predicting coloured glass content in different types of background material, but a different approach would be needed for predicting mixed type glass contamination in refuse-derived fuel.

Feldspathic rocks on Mars: Compositional constraints from infrared spectroscopy and possible formation mechanisms

AbstractRare feldspar‐dominated surfaces on Mars were previously reported based on near‐infrared (NIR) spectral data and were interpreted to consist of anorthosite or felsic rocks. Using thermal infrared (TIR) data over the feldspar detections with the largest areal extent in Nili Patera and Noachis Terra, we rule out felsic interpretations. Basaltic or anorthositic compositions are consistent with TIR measurements, but the geologic contexts for these regions do not support a plutonic origin. Laboratory NIR spectral measurements demonstrate that large plagioclase crystals (>~840 µm) can be detected in mixtures with as much as 50 vol % mafics, which is higher than the previously stated requirement of no more than 15% mafics. Thus, anorthositic or felsic interpretations need not be invoked for all NIR‐based feldspar detections. Plagioclase‐enriched basaltic eruptive products can be formed from Martian basalts through partial crystallization at the base of a thick crust, followed by low‐pressure crystallization of the residual liquids.

Near-Infrared Spectroscopy of Hayabusa Sample Return Capsule Reentry

As part of the 2010 airborne observational campaign for the Hayabusa capsule reentry, a system of four colocated cameras was deployed to track and measure the spacecraft fragmentation and sample return capsule descents. These instruments included an intensified video camera for narrow-field tracking, an intensified video camera for visible and near-infrared spectral measurements from 400 to 900 nm, and a near-infrared spectrograph for high-resolution measurements from 980 to 1080 nm. The latter was configured to monitor the spectral evolution of capsule emissions during descent, seeking evidence of possible carbon signatures due to ablation of the heat shield. The data complement previous Stardust capsule observations in which distinct 1069 nm emission signatures were measured, likely associated with carbon ablation from the Phenolic Impregnated Carbon Ablator heat shield. The Hayabusa capsule spectra also exhibited 1069 nm line emissions, appearing intermittently at , persisting from approximately 13:52:10 to 13:52:20 as the capsule approached peak heating, and weakening to undetectable levels after . Continuum emission and nitrogen line emissions were detected simultaneously. The evolutions of these signatures over the course of reentry are investigated, in comparison with model predictions and complementary campaign data.

A spectral comparison of (379) Huenna and its satellite

We present near-infrared spectral measurements of Themis family Asteroid (379) Huenna ( D ∼ 98 km) and its 6 km satellite using SpeX on the NASA IRTF. The companion was farther than 1.5″ from the primary at the time of observations and was approximately 5 magnitudes dimmer. We describe a method for separating and extracting the signal of a companion asteroid when the signal is not entirely resolved from the primary. The spectrum of (379) Huenna has a broad, shallow feature near 1 μm and a low slope, characteristic of C-type asteroids. The secondary’s spectrum is consistent with the taxonomic classification of C-complex or X-complex. The quality of the data was not sufficient to identify any subtle feature in the secondary’s spectrum.

Development and Design of Spectral Measurement Software System

This article mainly describes the technology and difficulties of the spectroscopic measurement software, analyzes the basic structure of the software system, proposes solutions according to functional requirements and creates the corresponding software with such functions. In the spectrum display aspect, it makes a more detailed description for the customized coordinate system and on the data processing module. It solves practical problems more conveniently through constructing a customized data structure, computing function. The Facts have proved that it is very convenient to develop near-infrared Spectral measurement system by using Visual Basic, which fully presents the language features of the Visual Basic.

Construction of an Efficacious Model for a Nondestructive Identification of Traditional Chinese Medicines Liuwei Dihuang Pills from Different Manufacturers Using Near-infrared Spectroscopy and Moving Window Partial Least-squares Discriminant Analysis

This paper reports on the construction of an efficacious model for a non-invasive identification of traditional Chinese medicines, Liuwei Dihuang pills from different manufacturers, on the basis of near-infrared spectra (NIRS) coupled with moving window partial least-squares discriminant analysis (MWPLSDA). Considering the continuity of near-infrared spectral measurements, MWPLSDA is used to identify continuous and highly classification-related information intervals, a simple, yet effective classification model that can be developed for identifying accurate 150 Liuwei Dihuang pills from five different manufacturers. Meanwhile, the method is compared with some traditional pattern-recognition methods including principal component analysis (PCA), linear discriminant analysis (LDA) and partial least-squares discriminant analysis (PLSDA). The obtained results show that the method not only can reduce the operation time, but also significantly improves the classification accuracy. Hence, the nondestructive method can be expected to be promising for more practical applications on quality control and the discrimination of traditional Chinese medicine.

Penggunaan Near Infrared Spectroscopy pada Penentuan Kandungan Padatan Terlarut Buah Mangga Indramayu Secara Tidak Merusak

Near infrared (NIR) spectroscopy appears as a prominent method for nondestructive fruit quality assessment. In this work, the relationship between the nondestructive NIR spectral measurements and the soluble solids content (SSC) of mango fruit was investigated. A number of 92 mango fruits (Mangifera indica var. Indramayu) were used as samples. The samples were divided into two groups, 46 samples for developing calibration model and 46 samples for performing validation. Using a portable spectrometer, spectra for each sample were acquired in absorbance mode at six different positions. The SSC of mango was measured using the digital refraktometer. The Partial Least Squares (PLS) regression was used to develop a calibration model. The NIR spectroscopy method successfully determined the sse of mango fruits with correlation coefficient between predicted and actual values (r) of 0.91, standard error of prediction (SEP) of 0. 74, and bias of 0.02. Keywords: NIR spectroscopy, soluble solids content, absorbance mode, nondestructive method,mangoDiterima: 18 Maret 2008; Disetujui: 17 Juli 2008

Spectral observations for near-Earth objects including potential target 4660 Nereus : Results from Meudon remote observations at the NASA Infrared Telescope Facility (IRTF)

We present visible and near-infrared spectral measurements for the highly accessible spacecraft target 4660 Nereus and three additional near-Earth objects displaying diverse color characteristics. All near-infrared measurements were carried out during the first remote observing operations between the Observatoire de Paris at Meudon and Mauna Kea, Hawaii. From Meudon, we had fine pointing and guiding control of the NASA Infrared Telescope Facility 3.0-m telescope and the near-infrared spectrograph “SpeX” to measure asteroid spectra in the range 0.8– 2.4 μm . The efficiency of the observation was virtually the same as if the observers had been on location. We combine our near-infrared results with complementary 0.4– 0.9 μm spectral measurements. Nereus is found to be a rare Xe-type asteroid with a composition that may be analogous to very high albedo enstatite achondrite (aubrite) meteorites, leading to a diameter estimate of less than 0.5 km . 1685 Toro displays a classic S-type spectrum while a steeper visible wavelength slope and a less pronounced 1 μm absorption feature for 1943 Anteros places it in the L-class. Also unusual is the apparent olivine-rich spectrum for 4142 Dersu-Uzala, which is classified as an A-type.

Determination of mango physiological indices by near-infrared spectrometry

The objectives of the study were to evaluate the use of near-infrared (NIR) spectrometry in measuring the physiological properties of mango fruit, cv. ‘Tommy Atkins’ and to establish relationships between the nondestructive NIR spectral measurements and the major physiological properties and quality indices of mango fruit. These include softening of the flesh, total soluble solids content and acidity. Intact mango fruit were measured by reflectance NIR in 1200–2400 nm range. NIR models were developed based on multi-linear regression (MLR), principal component analysis (PCA) and partial least square (PLS) regression with respect to the reflectance and its first derivative, the logarithms of the reflectance reciprocal and its second derivative. The above regression models, related the NIR spectra to storage period, firmness, sugar content and acidity. The best combination, based on the prediction results, was MLR models with respect to the second derivative logarithms of the reflectance reciprocal. Predictions with MLR models resulted standard errors of prediction (SEP) of 1.223, 0.161, 17.14 and 37.03, and coefficients of determination of 0.9276, 0.6085, 0.8226 and 0.9380 for TSS, acidity, firmness and storage period, respectively. It was concluded that by using the NIR spectrometry measurement system, in the appropriate spectral range, it is possible to nondestructively assess the maturity factors of mango fruit.

On the further observations ofB E /shell star V 923 Aql

V 923 Aql is one of the candidateB E stars to be a binary star. In this research, optical and near-infrared spectral measurements of V 923 Aql is presented. V 923 Aql presents variable H Balmer line profiles with shell components. Hα profiles present R/V, E/C and radial velocity variation. Shell parameters of the envelope are calculated.