[Application of near infrared spectroscopy technology (NIRS) in forage field].

PubMed

Yan, Xu; Bai, Shi-Qie; Yan, Jia-Jun; Gan, You-Min; Dao, Zhi-Xue

2012-07-01

The majority of nutrients in ruminants and other herbivores come from forages. Forage quality not only affects the growth and production efficiency of livestock, but also determines the final output and quality of livestock products. Forage quality mainly depends on nutrient concentrations and their digestibility, palatability and the level of presence of antiquality factors and mycotoxins in forage. Near infrared reflectance spectroscopy (NIRS) has been widely used in many research areas because it is a inexpensive, rapid, simple and nondestructive technique offering the potential for qualitative and quantitative analysis. The present paper briefly introduces the principle and characteristics of NIRS, detailedly expounds the application of NIRS in forage quality. In addition, other applications of near infrared spectroscopy technique in forage are also discussed, including forage breeding, identification of variety and classification by kind. This paper comprehensively reviews the status quo of application of NIRS in forage filed, in order to contribute to promoting development of NIRS in this field in China.

Classification of Fusarium-Infected Korean Hulled Barley Using Near-Infrared Reflectance Spectroscopy and Partial Least Squares Discriminant Analysis

PubMed Central

Lim, Jongguk; Kim, Giyoung; Mo, Changyeun; Oh, Kyoungmin; Yoo, Hyeonchae; Ham, Hyeonheui; Kim, Moon S.

2017-01-01

The purpose of this study is to use near-infrared reflectance (NIR) spectroscopy equipment to nondestructively and rapidly discriminate Fusarium-infected hulled barley. Both normal hulled barley and Fusarium-infected hulled barley were scanned by using a NIR spectrometer with a wavelength range of 1175 to 2170 nm. Multiple mathematical pretreatments were applied to the reflectance spectra obtained for Fusarium discrimination and the multivariate analysis method of partial least squares discriminant analysis (PLS-DA) was used for discriminant prediction. The PLS-DA prediction model developed by applying the second-order derivative pretreatment to the reflectance spectra obtained from the side of hulled barley without crease achieved 100% accuracy in discriminating the normal hulled barley and the Fusarium-infected hulled barley. These results demonstrated the feasibility of rapid discrimination of the Fusarium-infected hulled barley by combining multivariate analysis with the NIR spectroscopic technique, which is utilized as a nondestructive detection method. PMID:28974012

Sensing of moisture content in in-shell peanuts by NIR (Near Infra Red) reflectance spectroscopy

USDA-ARS?s Scientific Manuscript database

It was found earlier that moisture content (MC) of intact kernels of grain and nuts could be determined by Near Infra Red (NIR) reflectance spectrometry. However, if the MC values can be determined while the nuts are in their shells, it would save lot of labor and money spent in shelling and cleanin...

Application of near infrared spectroscopy (NIRS) to non-destructive internal quality inspection of tomatoes

NASA Astrophysics Data System (ADS)

Tao, Xuemei; He, Yong

2006-09-01

The internal quality of tomato such as acidity and sugar content is important to its taste thus influences the market. The objective of this paper was to demonstrate the feasibility of using a near-infrared spectroscopy (NIRS) to investigate the relationship between sugar content and acidity of tomato and absorption spectra. The N1RS reflectance of nondestructive tomatoes was measured with a Visible/NJR spectrophotometer in 325-1075 nm range. The sugar content and acidity of tomato were obtained with a handhold sugar content meter and a PH meter. The reflectance data set was recorded and analyzed with some mathematic methods. The PLS (Partial least squares) calibration method was developed for converting the NIRS reflectance of tomato into the data which determined the acidity value. BP (Back propagation) neural network was used to set up the relationship between the NIRS reflectance of tomato and sugar content. The acidity values were detected with an accuracy of 9O% and the sugar contents determined by the BP network were also very close to the measurements (coefficient of correlation r2=0.8764). NW spectra analysis would be very useful in the nondestructive internal quality inspecting of tomato.

Prediction of Caffeine Content in Java Preanger Coffee Beans by NIR Spectroscopy Using PLS and MLR Method

NASA Astrophysics Data System (ADS)

Budiastra, I. W.; Sutrisno; Widyotomo, S.; Ayu, P. C.

2018-05-01

Caffeine is one of important components in coffee that contributes to the coffee beverages flavor. Caffeine concentration in coffee bean is usually determined by chemical method which is time consuming and destructive method. A nondestructive method using NIR spectroscopy was successfully applied to determine the caffeine concentration of Arabica gayo coffee bean. In this study, NIR Spectroscopy was assessed to determine the caffeine concentration of java preanger coffee bean. A hundred samples, each consist of 96 g coffee beans were prepared for reflectance and chemical measurement. Reflectance of the sample was measured by FT-NIR spectrometer in the wavelength of 1000-2500 nm (10000-4000 cm-1) followed by determination of caffeine content using LCMS method. Calibration of NIR spectra and the caffeine content was carried out using PLS and MLR methods. Several spectra data processing was conducted to increase the accuracy of prediction. The result of the study showed that caffeine content could be determined by PLS model using 7 factors and spectra data processing of combination of the first derivative and MSC of spectra absorbance (r = 0.946; CV = 1.54 %; RPD = 2.28). A lower accuracy was obtained by MLR model consisted of three caffeine and other four absorption wavelengths (r = 0.683; CV = 3.31%; RPD = 1.18).

In-line and real-time process monitoring of a freeze drying process using Raman and NIR spectroscopy as complementary process analytical technology (PAT) tools.

PubMed

De Beer, T R M; Vercruysse, P; Burggraeve, A; Quinten, T; Ouyang, J; Zhang, X; Vervaet, C; Remon, J P; Baeyens, W R G

2009-09-01

The aim of the present study was to examine the complementary properties of Raman and near infrared (NIR) spectroscopy as PAT tools for the fast, noninvasive, nondestructive and in-line process monitoring of a freeze drying process. Therefore, Raman and NIR probes were built in the freeze dryer chamber, allowing simultaneous process monitoring. A 5% (w/v) mannitol solution was used as model for freeze drying. Raman and NIR spectra were continuously collected during freeze drying (one Raman and NIR spectrum/min) and the spectra were analyzed using principal component analysis (PCA) and multivariate curve resolution (MCR). Raman spectroscopy was able to supply information about (i) the mannitol solid state throughout the entire process, (ii) the endpoint of freezing (endpoint of mannitol crystallization), and (iii) several physical and chemical phenomena occurring during the process (onset of ice nucleation, onset of mannitol crystallization). NIR spectroscopy proved to be a more sensitive tool to monitor the critical aspects during drying: (i) endpoint of ice sublimation and (ii) monitoring the release of hydrate water during storage. Furthermore, via NIR spectroscopy some Raman observations were confirmed: start of ice nucleation, end of mannitol crystallization and solid state characteristics of the end product. When Raman and NIR monitoring were performed on the same vial, the Raman signal was saturated during the freezing step caused by reflected NIR light reaching the Raman detector. Therefore, NIR and Raman measurements were done on a different vial. Also the importance of the position of the probes (Raman probe above the vial and NIR probe at the bottom of the sidewall of the vial) in order to obtain all required critical information is outlined. Combining Raman and NIR spectroscopy for the simultaneous monitoring of freeze drying allows monitoring almost all critical freeze drying process aspects. Both techniques do not only complement each other, they also provided mutual confirmation of specific conclusions.

In-line multipoint near-infrared spectroscopy for moisture content quantification during freeze-drying.

PubMed

Kauppinen, Ari; Toiviainen, Maunu; Korhonen, Ossi; Aaltonen, Jaakko; Järvinen, Kristiina; Paaso, Janne; Juuti, Mikko; Ketolainen, Jarkko

2013-02-19

During the past decade, near-infrared (NIR) spectroscopy has been applied for in-line moisture content quantification during a freeze-drying process. However, NIR has been used as a single-vial technique and thus is not representative of the entire batch. This has been considered as one of the main barriers for NIR spectroscopy becoming widely used in process analytical technology (PAT) for freeze-drying. Clearly it would be essential to monitor samples that reliably represent the whole batch. The present study evaluated multipoint NIR spectroscopy for in-line moisture content quantification during a freeze-drying process. Aqueous sucrose solutions were used as model formulations. NIR data was calibrated to predict the moisture content using partial least-squares (PLS) regression with Karl Fischer titration being used as a reference method. PLS calibrations resulted in root-mean-square error of prediction (RMSEP) values lower than 0.13%. Three noncontact, diffuse reflectance NIR probe heads were positioned on the freeze-dryer shelf to measure the moisture content in a noninvasive manner, through the side of the glass vials. The results showed that the detection of unequal sublimation rates within a freeze-dryer shelf was possible with the multipoint NIR system in use. Furthermore, in-line moisture content quantification was reliable especially toward the end of the process. These findings indicate that the use of multipoint NIR spectroscopy can achieve representative quantification of moisture content and hence a drying end point determination to a desired residual moisture level.

Full scattering profile for detecting physiological tissue properties

NASA Astrophysics Data System (ADS)

Duadi, Hamootal; Fixler, Dror

2017-02-01

Light reflectance and transmission from soft tissue has been utilized in noninvasive clinical measurement devices such as the photoplethysmograph (PPG) and reflectance pulse oximeter. Most methods of near infrared (NIR) spectroscopy focus on the volume reflectance from a semi-infinite sample, while very few measure transmission. We have previously shown that examining the full scattering profile (FSP), which is the angular distribution of exiting photons, provides more comprehensive information when measuring from a cylindrical tissue, such as earlobe, fingertip and pinched tissue. Our hypothesis is that the change in blood vessel diameter is more significant than the change in optical properties. The findings of this work demonstrate a realistic model for optical tissue measurements such as NIR spectroscopy, PPG and pulse oximetery.

Analysis of Total Oil and Fatty Acids Composition by Near Infrared Reflectance Spectroscopy in Edible Nuts

USDA-ARS?s Scientific Manuscript database

Near Infrared (NIR) Reflectance spectroscopy has established itself as an important tool in quantifying water and oil present in various food materials. It is rapid and nondestructive, easier to use, and does not require processing the samples with corrosive chemicals that would render them non-edib...

[Applications of near infrared reflectance spectroscopy in detecting chitin, ergosterol and mycotoxins].

PubMed

Yi, Yong-Yan; Li, De-Rong; Zhang, Yun-Wei; Yang, Fu-Yu

2009-07-01

The invasion extent and harmfulness of fungi can be determined by chitin, ergosterol and mycotoxins. It is important to monitor chitin, ergosterol and mycotoxins changes to prevent contamination of forage and feed products, and effectively control the sustainable development of the mildew. Predication of these chemical materials was often completed by laboratory analysis, which was time-consuming and cumbersome and could not reflect the results in time in the past. Near infrared reflectance spectroscopy (NIRS) is a rapid, convenient, highly efficient, nondestructive and low-cost analytical technique, which has been widely used in various fields such as food field and feed field for quantitative and qualitative analysis. It has a great potentiality of application in quality analysis. In this paper, the principle and the characteristic of NIRS and its applications in food, forage, feed and other agriculture products quality analysis were introduced. Its applications in fungal biomass (chitin, ergosterol) and mycotoxins were mainly reviewed. NIRS was used to quantify chitin, ergosterol and mycotoxins. Calibration equations and validation equations for these materials were developed. It is also expected that NIRS will play a more and more important role in the field of fungi with the establishment of calibration equation and improvement of model database.

Near infrared diffuse reflection and laser-induced fluorescence spectroscopy for myocardial tissue characterisation

NASA Astrophysics Data System (ADS)

Nilsson, A. M. K.; Heinrich, D.; Olajos, J.; Andersson-Engels, S.

1997-10-01

In order to evaluate the potential of cardiovascular tissue characterisation using near-infrared (NIR) spectroscopy, spectra in a previously unexplored wavelength region 0.8-2.3 μm were recorded from various pig heart tissue samples in vitro: normal myocardium (with and without endo/epicardium), aorta, fatty and fibrous heart tissue. The spectra were analysed with principal component analysis (PCA), revealing several spectroscopically characteristic features enabling tissue classification. Several of the identified spectral features could be attributed to specific tissue constituents by comparing the tissue signals with spectra obtained from water, elastin, collagen and cholesterol as well as with published data. The results obtained with the NIR spectroscopy technique in terms of its potential to classify different tissue types were compared with those from laser-induced fluorescence (LIF) using 337 nm excitation. LIF and NIR spectroscopy can in combination with PCA be used to discriminate between all previously mentioned tissue groups, apart from fatty versus fibrous tissue (LIF) and aorta versus fibrous tissue (NIR), respectively. The NIR analysis was improved by focusing the PCA to the wavelength segment 2.0-2.3 μm, resulting in successful spectral characterisation of all cardiovascular tissue groups.

[Near-infrared reflectance spectroscopy predicts protein, moisture and ash in beans].

PubMed

Gao, Huiyu; Wang, Guodong; Men, Jianhua; Wang, Zhu

2017-05-01

To explore the potential of near-infrared reflectance( NIR)spectroscopy to determine macronutrient contents in beans. NIR spectra and analytical measurements of protein, moisture and ash were collected from 70 kinds of beans. Reference methods were used to analyze all the ground beans samples. NIR spectra on intact and ground beans samples were registered. Partial least-squares( PLS)regression models were developed with principal components analysis( PCA) to assign 49 bean accessions to a calibration data set and 21 accessions to an external validation set. For intact beans, the relative predictive determinant( RPD) values for protein and ash( 3. 67 and 3. 97, respectively) were good for screening. RPD value for moisture was only 1. 39, which was not recommended. For ground beans, the RPD values for protein, moisture and ash( 6. 63, 5. 25 and 3. 57, respectively) were good enough for screening. The protein, moisture and ash levels for intact and ground beans were all significantly correlated( P < 0. 001) between the NIR and reference method and there was no statistically significant difference in the mean with these three traits. This research demonstrates that NIR is a promising technique for simultaneous sorting ofmultiple traits in beans with no or easy sample preparation.

Fast determination of total ginsenosides content in ginseng powder by near infrared reflectance spectroscopy

NASA Astrophysics Data System (ADS)

Chen, Hua-cai; Chen, Xing-dan; Lu, Yong-jun; Cao, Zhi-qiang

2006-01-01

Near infrared (NIR) reflectance spectroscopy was used to develop a fast determination method for total ginsenosides in Ginseng (Panax Ginseng) powder. The spectra were analyzed with multiplicative signal correction (MSC) correlation method. The best correlative spectra region with the total ginsenosides content was 1660 nm~1880 nm and 2230nm~2380 nm. The NIR calibration models of ginsenosides were built with multiple linear regression (MLR), principle component regression (PCR) and partial least squares (PLS) regression respectively. The results showed that the calibration model built with PLS combined with MSC and the optimal spectrum region was the best one. The correlation coefficient and the root mean square error of correction validation (RMSEC) of the best calibration model were 0.98 and 0.15% respectively. The optimal spectrum region for calibration was 1204nm~2014nm. The result suggested that using NIR to rapidly determinate the total ginsenosides content in ginseng powder were feasible.

Quantification of betaglucans, lipid and protein contents in whole oat groats (Avena sativa L.) using near infrared reflectance spectroscopy

USDA-ARS?s Scientific Manuscript database

Whole oat has been described as an important healthy food for humans due to its beneficial nutritional components. Near infrared reflectance spectroscopy (NIRS) is a powerful, fast, accurate and non-destructive analytical tool that can be substituted for some traditional chemical analysis. A total o...

Utilization of functional near infrared spectroscopy for non-invasive evaluation

NASA Astrophysics Data System (ADS)

Halim, A. A. A.; Laili, M. H.; Aziz, N. A.; Laili, A. R.; Salikin, M. S.; Rusop, M.

2016-07-01

The goal of this brief review is to report the techniques of functional near infrared spectroscopy for non-invasive evaluation in human study. The development of functional near infrared spectroscopy (fNIRS) technologies has advanced quantification signal using multiple wavelength and detector to solve the propagation of light inside the tissues including the absorption, scattering coefficient and to define the light penetration into tissues multilayers. There are a lot of studies that demonstrate signal from fNIRS which can be used to evaluate the changes of oxygenation level and measure the limitation of muscle performance in human brain and muscle tissues. Comprehensive reviews of diffuse reflectance based on beer lambert law theory were presented in this paper. The principle and development of fNIRS instrumentation is reported in detail.

Dynamic changes in near-infrared spectroscopy (NIRS) findings in first-episode schizophrenia: a case report.

PubMed

Hatakeyama, Tsuyoshi; Kunii, Yasuto; Miura, Itaru; Itagaki, Shuntaro; Kono, Soichi; Shiga, Tetsuya; Oshima, Sachie; Nozaki, Keiko; Suzuki, Rieko; Yabe, Hirooki

2017-04-28

The clinical course of schizophrenia is characterized by recurrence and chronicity and has a large burden on society.　Nevertheless, diagnosis of schizophrenia is based only on distinctive symptoms and the disease course.　Near-infrared spectroscopy (NIRS) is a useful method for measuring changes in the hemoglobin concentration in the cortical surface area and reflects brain function.　We measured NIRS four times during the clinical course in a patient with first-episode schizophrenia.A 17-year-old woman admitted to our hospital because of hallucinations, delusions and appetite loss. After treatment with low-dose antipsychotics, NIRS findings showed a prompt increase in the cerebral blood volume in the frontal region.　On the basis of the clinical course of this patient, we introduce a new point of view, namely, that NIRS findings may be useful as a state marker that indicates the severity of schizophrenia in some cases.

Dynamic changes in near-infrared spectroscopy (NIRS) findings in first-episode schizophrenia: a case report

PubMed Central

Hatakeyama, Tsuyoshi; Kunii, Yasuto; Miura, Itaru; Itagaki, Shuntaro; Kono, Soichi; Shiga, Tetsuya; Oshima, Sachie; Nozaki, Keiko; Suzuki, Rieko; Yabe, Hirooki

2017-01-01

Abstract The clinical course of schizophrenia is characterized by recurrence and chronicity and has a large burden on society. Nevertheless, diagnosis of schizophrenia is based only on distinctive symptoms and the disease course. Near-infrared spectroscopy (NIRS) is a useful method for measuring changes in the hemoglobin concentration in the cortical surface area and reflects brain function. We measured NIRS four times during the clinical course in a patient with first-episode schizophrenia. A 17-year-old woman admitted to our hospital because of hallucinations, delusions and appetite loss. After treatment with low-dose antipsychotics, NIRS findings showed a prompt increase in the cerebral blood volume in the frontal region. On the basis of the clinical course of this patient, we introduce a new point of view, namely, that NIRS findings may be useful as a state marker that indicates the severity of schizophrenia in some cases. PMID:28420824

Mapping The Temporal and Spatial Variability of Soil Moisture Content Using Proximal Soil Sensing

NASA Astrophysics Data System (ADS)

Virgawati, S.; Mawardi, M.; Sutiarso, L.; Shibusawa, S.; Segah, H.; Kodaira, M.

2018-05-01

In studies related to soil optical properties, it has been proven that visual and NIR soil spectral response can predict soil moisture content (SMC) using proper data analysis techniques. SMC is one of the most important soil properties influencing most physical, chemical, and biological soil processes. The problem is how to provide reliable, fast and inexpensive information of SMC in the subsurface from numerous soil samples and repeated measurement. The use of spectroscopy technology has emerged as a rapid and low-cost tool for extensive investigation of soil properties. The objective of this research was to develop calibration models based on laboratory Vis-NIR spectroscopy to estimate the SMC at four different growth stages of the soybean crop in Yogyakarta Province. An ASD Field-spectrophotoradiometer was used to measure the reflectance of soil samples. The partial least square regression (PLSR) was performed to establish the relationship between the SMC with Vis-NIR soil reflectance spectra. The selected calibration model was used to predict the new samples of SMC. The temporal and spatial variability of SMC was performed in digital maps. The results revealed that the calibration model was excellent for SMC prediction. Vis-NIR spectroscopy was a reliable tool for the prediction of SMC.

Rapid and quantitative detection of the microbial spoilage in chicken meat by diffuse reflectance spectroscopy (600-1100 nm).

PubMed

Lin, M; Al-Holy, M; Mousavi-Hesary, M; Al-Qadiri, H; Cavinato, A G; Rasco, B A

2004-01-01

To evaluate the feasibility of visible and short-wavelength near-infrared (SW-NIR) diffuse reflectance spectroscopy (600-1100 nm) to quantify the microbial loads in chicken meat and to develop a rapid methodology for monitoring the onset of spoilage. Twenty-four prepackaged fresh chicken breast muscle samples were prepared and stored at 21 degrees C for 24 h. Visible and SW-NIR was used to detect and quantify the microbial loads in chicken breast muscle at time intervals of 0, 2, 4, 6, 8, 10, 12 and 24 h. Spectra were collected in the diffuse reflectance mode (600-1100 nm). Total aerobic plate count (APC) of each sample was determined by the spread plate method at 32 degrees C for 48 h. Principal component analysis (PCA) and partial least squares (PLS) based prediction models were developed. PCA analysis showed clear segregation of samples held 8 h or longer compared with 0-h control. An optimum PLS model required eight latent variables for chicken muscle (R = 0.91, SEP = 0.48 log CFU g(-1)). Visible and SW-NIR combined with PCA is capable of perceiving the change of the microbial loads in chicken muscle once the APC increases slightly above 1 log cycle. Accurate quantification of the bacterial loads in chicken muscle can be calculated from the PLS-based prediction method. Visible and SW-NIR spectroscopy is a technique with a considerable potential for monitoring food safety and food spoilage. Visible and SW-NIR can acquire a metabolic snapshot and quantify the microbial loads of food samples rapidly, accurately, and noninvasively. This method would allow for more expeditious applications of quality control in food industries.

A novel combined approach of diffuse reflectance UV-Vis-NIR spectroscopy and multivariate analysis for non-destructive examination of blue ballpoint pen inks in forensic application

NASA Astrophysics Data System (ADS)

Kumar, Raj; Sharma, Vishal

2017-03-01

The present research is focused on the analysis of writing inks using destructive UV-Vis spectroscopy (dissolution of ink by the solvent) and non-destructive diffuse reflectance UV-Vis-NIR spectroscopy along with Chemometrics. Fifty seven samples of blue ballpoint pen inks were analyzed under optimum conditions to determine the differences in spectral features of inks among same and different manufacturers. Normalization was performed on the spectroscopic data before chemometric analysis. Principal Component Analysis (PCA) and K-mean cluster analysis were used on the data to ascertain whether the blue ballpoint pen inks could be differentiated by their UV-Vis/UV-Vis NIR spectra. The discriminating power is calculated by qualitative analysis by the visual comparison of the spectra (absorbance peaks), produced by the destructive and non-destructive methods. In the latter two methods, the pairwise comparison is made by incorporating the clustering method. It is found that chemometric method provides better discriminating power (98.72% and 99.46%, in destructive and non-destructive, respectively) in comparison to the qualitative analysis (69.67%).

Detecting and Segregating Black Tip-Damaged Wheat Kernels Using Visible and Near Infrared Spectroscopy

USDA-ARS?s Scientific Manuscript database

Detection of individual wheat kernels with black tip symptom (BTS) and black tip damage (BTD) was demonstrated using near infrared reflectance spectroscopy (NIRS) and silicon light-emitting-diode (LED) based instruments. The two instruments tested, a single kernel near-infrared spectroscopy instrume...

Predicting glycogen concentration in the foot muscle of abalone using near infrared reflectance spectroscopy (NIRS).

PubMed

Fluckiger, Miriam; Brown, Malcolm R; Ward, Louise R; Moltschaniwskyj, Natalie A

2011-06-15

Near infrared reflectance spectroscopy (NIRS) was used to predict glycogen concentrations in the foot muscle of cultured abalone. NIR spectra of live, shucked and freeze-dried abalones were modelled against chemically measured glycogen data (range: 0.77-40.9% of dry weight (DW)) using partial least squares (PLS) regression. The calibration models were then used to predict glycogen concentrations of test abalone samples and model robustness was assessed from coefficient of determination of the validation (R2(val)) and standard error of prediction (SEP) values. The model for freeze-dried abalone gave the best prediction (R2(val) 0.97, SEP=1.71), making it suitable for quantifying glycogen. Models for live and shucked abalones had R2(val) of 0.86 and 0.90, and SEP of 3.46 and 3.07 respectively, making them suitable for producing estimations of glycogen concentration. As glycogen is a taste-active component associated with palatability in abalone, this study demonstrated the potential of NIRS as a rapid method to monitor the factors associated with abalone quality. Copyright © 2011 Elsevier Ltd. All rights reserved.

Near-infrared reflectance spectroscopy predicts protein, starch, and seed weight in intact seeds of common bean ( Phaseolus vulgaris L.).

PubMed

Hacisalihoglu, Gokhan; Larbi, Bismark; Settles, A Mark

2010-01-27

The objective of this study was to explore the potential of near-infrared reflectance (NIR) spectroscopy to determine individual seed composition in common bean ( Phaseolus vulgaris L.). NIR spectra and analytical measurements of seed weight, protein, and starch were collected from 267 individual bean seeds representing 91 diverse genotypes. Partial least-squares (PLS) regression models were developed with 61 bean accessions randomly assigned to a calibration data set and 30 accessions assigned to an external validation set. Protein gave the most accurate PLS regression, with the external validation set having a standard error of prediction (SEP) = 1.6%. PLS regressions for seed weight and starch had sufficient accuracy for seed sorting applications, with SEP = 41.2 mg and 4.9%, respectively. Seed color had a clear effect on the NIR spectra, with black beans having a distinct spectral type. Seed coat color did not impact the accuracy of PLS predictions. This research demonstrates that NIR is a promising technique for simultaneous sorting of multiple seed traits in single bean seeds with no sample preparation.

Fabrication and characterization of environmental-friendly Ni1-xRxTiO3 nanopigments with high NIR reflectance

NASA Astrophysics Data System (ADS)

Tong, Yu-Ping; Chen, Zheng; Wang, Hui-Xian; Zhang, Xu-Fang; Ma, Jun-Tao; Chen, Xi

2015-04-01

A series of novel high dispersed environmental-friendly nanopigments based on NiTiO3 doped with rare earth ion such as Y, La, Eu, Sm have been developed. The products were characterized by X-ray diffractometer (XRD), scanning electron microscopy (SEM), commission internationale de l'Eclairage (CIE) 1976 L*α*b* color scales and UV-Vis-near-infrared radiation (NIR) reflectance spectroscopy. The substitution of R3+ for Ni2+ in NiTiO3 can improve the yellowness of pigments, especially for Eu3+ substitution. The sample with the substitution of Eu3+ for Ni2+ processes the highest NIR reflectance and enhances the NIR reflectance to 89.0%. SEM results revealed that the obtained pigments were composed of well-dispersed spherical-like particles with the range of 40-60 nm. EDS results indicated that the distribution of Ni, Ti, R, O element was considerably uniform with no chemical segregation phenomenon.

Use of near infrared spectroscopy for the clinical monitoring of adult brain

NASA Astrophysics Data System (ADS)

Kirkpatrick, Peter J.; Smielewski, P.; Lam, J. M.; Al-Rawi, P.

1996-10-01

Adult near infrared spectroscopy (NIRS) is a potential method for noninvasively assessing changes in cerebral oxygenation. Unlike neonatal NIRS, access of light to the adult rain requires penetration through thick extracranial tissues, and hence detection of changed in cerebral chromophore concentration can only be achieved by using NIRS in the reflectance mode. This adds variables that are difficult to control. They include the effects of a different intraoptode distance, intersubject anatomical variation, and the influence of a pathological extra- to intracranial collateral blood supply. Although studies showing movements of oxyhemoglobin concentration following specific cerebral stimuli have been published, the separation of changes occurring in the extracranial and intracranial compartments remains a challenge. Experience with NIRS in the three adult clinical scenarios of carotid endarterectomy, head injury, and carbon dioxide stress testing is presented. The influence of extracranial contamination is demonstrated, as are the methods adopted to help control for extracranial blood flow changes. Provisional experience with spatially responded spectroscopy technology is also discussed.

Classification of specialty seed meals from NIR reflectance spectra

USDA-ARS?s Scientific Manuscript database

Near infrared reflectance spectroscopy was used to identify alternative seed meals proposed for food and feed formulations. Spectra were collected from cold pressed Camelina (Camelina sativa), Coriander (Coriandrum sativum), and Pennycress (Thlaspi arvense) meals. Additional spectra were collected ...

Near-infrared imaging spectroscopy for counterfeit drug detection

NASA Astrophysics Data System (ADS)

Arnold, Thomas; De Biasio, Martin; Leitner, Raimund

2011-06-01

Pharmaceutical counterfeiting is a significant issue in the healthcare community as well as for the pharmaceutical industry worldwide. The use of counterfeit medicines can result in treatment failure or even death. A rapid screening technique such as near infrared (NIR) spectroscopy could aid in the search for and identification of counterfeit drugs. This work presents a comparison of two laboratory NIR imaging systems and the chemometric analysis of the acquired spectroscopic image data. The first imaging system utilizes a NIR liquid crystal tuneable filter and is designed for the investigation of stationary objects. The second imaging system utilizes a NIR imaging spectrograph and is designed for the fast analysis of moving objects on a conveyor belt. Several drugs in form of tablets and capsules were analyzed. Spectral unmixing techniques were applied to the mixed reflectance spectra to identify constituent parts of the investigated drugs. The results show that NIR spectroscopic imaging can be used for contact-less detection and identification of a variety of counterfeit drugs.

Pattern recognition of visible and near-infrared spectroscopy from bayberry juice by use of partial least squares and a backpropagation neural network

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cen Haiyan; Bao Yidan; He Yong

2006-10-10

Visible and near-infrared reflectance (visible-NIR) spectroscopy is applied to discriminate different varieties of bayberry juices. The discrimination of visible-NIR spectra from samples is a matter of pattern recognition. By partial least squares (PLS), the spectrum is reduced to certain factors, which are then taken as the input of the backpropagation neural network (BPNN). Through training and prediction, three different varieties of bayberry juice are classified based on the output of the BPNN. In addition, a mathematical model is built and the algorithm is optimized. With proper parameters in the training set,100% accuracy is obtained by the BPNN. Thus it ismore » concluded that the PLS analysis combined with the BPNN is an alternative for pattern recognition based on visible and NIR spectroscopy.« less

A novel combined approach of diffuse reflectance UV-Vis-NIR spectroscopy and multivariate analysis for non-destructive examination of blue ballpoint pen inks in forensic application.

PubMed

Kumar, Raj; Sharma, Vishal

2017-03-15

The present research is focused on the analysis of writing inks using destructive UV-Vis spectroscopy (dissolution of ink by the solvent) and non-destructive diffuse reflectance UV-Vis-NIR spectroscopy along with Chemometrics. Fifty seven samples of blue ballpoint pen inks were analyzed under optimum conditions to determine the differences in spectral features of inks among same and different manufacturers. Normalization was performed on the spectroscopic data before chemometric analysis. Principal Component Analysis (PCA) and K-mean cluster analysis were used on the data to ascertain whether the blue ballpoint pen inks could be differentiated by their UV-Vis/UV-Vis NIR spectra. The discriminating power is calculated by qualitative analysis by the visual comparison of the spectra (absorbance peaks), produced by the destructive and non-destructive methods. In the latter two methods, the pairwise comparison is made by incorporating the clustering method. It is found that chemometric method provides better discriminating power (98.72% and 99.46%, in destructive and non-destructive, respectively) in comparison to the qualitative analysis (69.67%). Copyright © 2016 Elsevier B.V. All rights reserved.

Use of near-infrared spectroscopy (NIRS) in cerebral tissue oxygenation monitoring in neonates.

PubMed

Gumulak, Rene; Lucanova, Lucia Casnocha; Zibolen, Mirko

2017-06-01

Near-infrared spectroscopy (NIRS) is a technology capable of non-invasive, continuous measuring of regional tissue oxygen saturation (StO 2 ). StO 2 represents a state of hemodynamic stability, which is influenced by many factors. Extensive research has been done in the field of measuring StO 2 of various organs. The current clinical availability of several NIRS-based devices reflects an important development in prevention, detection and correction of discrepancy in oxygen delivery to the brain and vital organs. Managing cerebral ischemia remains a significant issue in the neonatal intensive care units (NICU). Cerebral tissue oxygenation (cStO 2 ) and cerebral fractional tissue extraction (cFTOE) are reported in a large number of clinical studies. This review provides a summary of the concept of function, current variability of NIRS-based devices used in neonatology, clinical applications in continuous cStO 2 monitoring, limitations, disadvantages, and the potential of current technology.

Development of a method for the determination of caffeine anhydrate in various designed intact tablets [correction of tables] by near-infrared spectroscopy: a comparison between reflectance and transmittance technique.

PubMed

Ito, Masatomo; Suzuki, Tatsuya; Yada, Shuichi; Kusai, Akira; Nakagami, Hiroaki; Yonemochi, Etsuo; Terada, Katsuhide

2008-08-05

Using near-infrared (NIR) spectroscopy, an assay method which is not affected by such elements of tablet design as thickness, shape, embossing and scored line was developed. Tablets containing caffeine anhydrate were prepared by direct compression at various compression force levels using different shaped punches. NIR spectra were obtained from these intact tablets using the reflectance and transmittance techniques. A reference assay was performed by high-performance liquid chromatography (HPLC). Calibration models were generated by the partial least-squares (PLS) regression. Changes in the tablet thickness, shape, embossing and scored line caused NIR spectral changes in different ways, depending on the technique used. As a result, noticeable errors in drug content prediction occurred using calibration models generated according to the conventional method. On the other hand, when the various tablet design elements which caused the NIR spectral changes were included in the model, the prediction of the drug content in the tablets was scarcely affected by those elements when using either of the techniques. A comparison of these techniques resulted in higher predictability under the tablet design variations using the transmittance technique with preferable linearity and accuracy. This is probably attributed to the transmittance spectra which sensitively reflect the differences in tablet thickness or shape as a result of obtaining information inside the tablets.

Diagnosis of colorectal cancer by near-infrared optical fiber spectroscopy and random forest

NASA Astrophysics Data System (ADS)

Chen, Hui; Lin, Zan; Wu, Hegang; Wang, Li; Wu, Tong; Tan, Chao

2015-01-01

Near-infrared (NIR) spectroscopy has such advantages as being noninvasive, fast, relatively inexpensive, and no risk of ionizing radiation. Differences in the NIR signals can reflect many physiological changes, which are in turn associated with such factors as vascularization, cellularity, oxygen consumption, or remodeling. NIR spectral differences between colorectal cancer and healthy tissues were investigated. A Fourier transform NIR spectroscopy instrument equipped with a fiber-optic probe was used to mimic in situ clinical measurements. A total of 186 spectra were collected and then underwent the preprocessing of standard normalize variate (SNV) for removing unwanted background variances. All the specimen and spots used for spectral collection were confirmed staining and examination by an experienced pathologist so as to ensure the representative of the pathology. Principal component analysis (PCA) was used to uncover the possible clustering. Several methods including random forest (RF), partial least squares-discriminant analysis (PLSDA), K-nearest neighbor and classification and regression tree (CART) were used to extract spectral features and to construct the diagnostic models. By comparison, it reveals that, even if no obvious difference of misclassified ratio (MCR) was observed between these models, RF is preferable since it is quicker, more convenient and insensitive to over-fitting. The results indicate that NIR spectroscopy coupled with RF model can serve as a potential tool for discriminating the colorectal cancer tissues from normal ones.

Non-destructive prediction of 'Hass' avocado dry matter via FT-NIR spectroscopy.

PubMed

Wedding, Brett B; White, Ronald D; Grauf, Steve; Wright, Carole; Tilse, Bonnie; Hofman, Peter; Gadek, Paul A

2011-01-30

The inability to consistently guarantee internal quality of horticulture produce is of major importance to the primary producer, marketers and ultimately the consumer. Currently, commercial avocado maturity estimation is based on the destructive assessment of percentage dry matter (%DM), and sometimes percentage oil, both of which are highly correlated with maturity. In this study the utility of Fourier transform (FT) near-infrared spectroscopy (NIRS) was investigated for the first time as a non-invasive technique for estimating %DM of whole intact 'Hass' avocado fruit. Partial least squares regression models were developed from the diffuse reflectance spectra to predict %DM, taking into account effects of intra-seasonal variation and orchard conditions. It was found that combining three harvests (early, mid and late) from a single farm in the major production district of central Queensland yielded a predictive model for %DM with a coefficient of determination for the validation set of 0.76 and a root mean square error of prediction of 1.53% for DM in the range 19.4-34.2%. The results of the study indicate the potential of FT-NIRS in diffuse reflectance mode to non-invasively predict %DM of whole 'Hass' avocado fruit. When the FT-NIRS system was assessed on whole avocados, the results compared favourably against data from other NIRS systems identified in the literature that have been used in research applications on avocados. 2010 Society of Chemical Industry.

Quality assessment of tomato landraces and virus-resistant breeding lines: quick estimation by near infrared reflectance spectroscopy.

PubMed

García-Martínez, Santiago; Gálvez-Sola, Luis N; Alonso, Arantxa; Agulló, Enrique; Rubio, Fernando; Ruiz, Juan J; Moral, Raúl

2012-04-01

Several tomato landraces are very popular in south-eastern Spain for their organoleptic fruit quality, but these cultivars are highly susceptible to several viruses. A breeding programme is being carried out for the introduction of virus resistances into these landraces. In the last steps of our breeding programme a high number of breeding lines must be evaluated for agronomic and organoleptic quality parameters. Near infrared reflectance spectroscopy (NIRS) technology shows considerable promise and is ideally suited to the requirements of breeders. Significant differences between a set of 35 tomato breeding lines, seven landraces and one commercial hybrid were observed for quality and mineral content parameters, suggesting that there are considerable levels of genetic diversity between the cultivar groups studied. Using NIRS on dry samples of tomato constitutes a feasible technique to estimate the content of several minerals (C, N, P, K, Ca, Na, Mn, Mg and Cu) according to the coefficient of determination for calibration (R(2) > 0.90). NIRS estimations of soluble solids content and titratable acidity obtained were considered useful only for general screening purposes. NIRS technology may be a useful tool in the selection of lines coming out of tomato breeding programs, allowing a quick estimation of mineral content. However, the estimation of soluble solids content and titratable acidity by NIRS must be improved. Copyright © 2011 Society of Chemical Industry.

Comparison of visible and near infrared reflectance spectroscopy on fat to authenticate dietary history of lambs.

PubMed

Huang, Y; Andueza, D; de Oliveira, L; Zawadzki, F; Prache, S

2015-11-01

Since consumers are showing increased interest in the origin and method of production of their food, it is important to be able to authenticate dietary history of animals by rapid and robust methods used in the ruminant products. Promising breakthroughs have been made in the use of spectroscopic methods on fat to discriminate pasture-fed and concentrate-fed lambs. However, questions remained on their discriminatory ability in more complex feeding conditions, such as concentrate-finishing after pasture-feeding. We compared the ability of visible reflectance spectroscopy (Vis RS, wavelength range: 400 to 700 nm) with that of visible-near-infrared reflectance spectroscopy (Vis-NIR RS, wavelength range: 400 to 2500 nm) to differentiate between carcasses of lambs reared with three feeding regimes, using partial least square discriminant analysis (PLS-DA) as a classification method. The sample set comprised perirenal fat of Romane male lambs fattened at pasture (P, n = 69), stall-fattened indoors on commercial concentrate and straw (S, n = 55) and finished indoors with concentrate and straw for 28 days after pasture-feeding (PS, n = 65). The overall correct classification rate was better for Vis-NIR RS than for Vis RS (99.0% v. 95.1%, P < 0.05). Vis-NIR RS allowed a correct classification rate of 98.6%, 100.0% and 98.5% for P, S and PS lambs, respectively, whereas Vis RS allowed a correct classification rate of 98.6%, 94.5% and 92.3% for P, S and PS lambs, respectively. This study suggests the likely implication of molecules absorbing light in the non-visible part of the Vis-NIR spectra (possibly fatty acids), together with carotenoid and haem pigments, in the discrimination of the three feeding regimes.

Analysis of ecstasy tablets: comparison of reflectance and transmittance near infrared spectroscopy.

PubMed

Schneider, Ralph Carsten; Kovar, Karl-Artur

2003-07-08

Calibration models for the quantitation of commonly used ecstasy substances have been developed using near infrared spectroscopy (NIR) in diffuse reflectance and in transmission mode by applying seized ecstasy tablets for model building and validation. The samples contained amphetamine, N-methyl-3,4-methylenedioxy-amphetamine (MDMA) and N-ethyl-3,4-methylenedioxy-amphetamine (MDE) in different concentrations. All tablets were analyzed using high performance liquid chromatography (HPLC) with diode array detection as reference method. We evaluated the performance of each NIR measurement method with regard to its ability to predict the content of each tablet with a low root mean square error of prediction (RMSEP). Best calibration models could be generated by using NIR measurement in transmittance mode with wavelength selection and 1/x-transformation of the raw data. The models build in reflectance mode showed higher RMSEPs using as data pretreatment, wavelength selection, 1/x-transformation and a second order Savitzky-Golay derivative with five point smoothing was applied to obtain the best models. To estimate the influence of inhomogeneities in the illegal tablets, a calibration of the destroyed, i.e. triturated samples was build and compared to the corresponding data of the whole tablets. The calibrations using these homogenized tablets showed lower RMSEPs. We can conclude that NIR analysis of ecstasy tablets in transmission mode is more suitable than measurement in diffuse reflectance to obtain quantification models for their active ingredients with regard to low errors of prediction. Inhomogeneities in the samples are equalized when measuring the tablets as powdered samples.

VIS/NIR reflectance and fluorescence spectrometric studies of minerals, water, organics and biomarkers in MoonMars analogue samples

NASA Astrophysics Data System (ADS)

Vos, Heleen; Foing, Bernard; Kołodziejczyk, Agata; Vago, Jorge; Harasymczuk, Matt

2017-04-01

This study focuses on the detection and characterisation of elements, minerals, volatiles and organics using reflectance spectrometry. The goal is to create a calibration method to enable the use of spectrometers on analogue Moon/Mars missions and on a lander. For this study we use measurements that are done in the VIS and NIR spectrum, as well as fluorescence using different spectrometers. The first part of the study consists of measurements that are performed in a laboratory to create a calibration method. Different rock samples and soils are analysed and the reflectance and absorption of minerals, water, organics and biomarkers are measured. Also the influence of the grain size, light source and surroundings is being determined. An experiment on the reflectance spectra of plant growth in different soils is also done to determine the possibilities of detecting the presence of chlorophyll and other biomarkers, and to diagnose the growth and health of a plant. This analysis can result in a monitoring method for a Moon greenhouse, but also for general surface analysis. Using VIS and NIR spectrometry has a couple of advantages, one being the fact that measurements require no sample preparation, and also the small size of the spectrometer makes it an easy tool for different analyses on board space missions. However, VIS and NIR spectroscopy have detection limits which makes only certain characteristics detectable. Besides laboratory measurements, the different spectroscopy methods are tested during a field campaign in the Eifel, Germany. During this campaign we can determine the functionality of the spectrometer in the field and on a lander and the problems that can rise when a spectrometer is controlled from a distant or by a person who is not trained in using spectroscopy. These laboratory and field measurements can help in the scientific preparation for instruments on ExoMars rover, future MoonMars lander missions and for the MoonVillage.

Near-infrared spectroscopy for burning plasma diagnostic applications.

PubMed

Soukhanovskii, V A

2008-10-01

Ultraviolet and visible (UV-VIS, 200-750 nm) atomic spectroscopy of neutral and ionized fuel species (H, D, T, and Li) and impurities (e.g., He, Be, C, and W) is a key element of plasma control and diagnosis on International Thermonuclear Experimental Reactor and future magnetically confined burning plasma experiments (BPXs). Spectroscopic diagnostic implementation and performance issues that arise in the BPX harsh nuclear environment in the UV-VIS range, e.g., degradation of first mirror reflectivity under charge-exchange atom bombardment (erosion) and impurity deposition, permanent and dynamic loss of window, and optical fiber transmission under intense neutron and gamma-ray fluxes, are either absent or not as severe in the near-infrared (NIR, 750-2000 nm) range. An initial survey of NIR diagnostic applications has been undertaken on the National Spherical Torus Experiment. It is demonstrated that NIR spectroscopy can be used for machine protection and plasma control applications, as well as contribute to plasma performance evaluation and physics studies. Emission intensity estimates demonstrate that NIR measurements are possible in the BPX plasma operating parameter range. Complications in the NIR range due to the parasitic background emissions are expected to occur at very high plasma densities, low impurity densities, and at high plasma-facing component temperatures.

[Applications of near infrared reflectance spectroscopy technique to determination of forage mycotoxins].

PubMed

Xu, Qing-Fang; Han, Jian-Guo; Yu, Zhu; Yue, Wen-Bin

2010-05-01

The near infrared reflectance spectroscopy technique (NIRS) has been explored at many fields such as agriculture, food, chemical, medicine, and so on, due to its rapid, effective, non-destructive, and on-line characteristics. Fungi invasion in forage materials during processing and storage would generate mycotoxins, which were harmful for people and animal through food chains. The determination of mycotoxins included the overelaborated pretreatments such as milling, extracting, chromatography and subsequent process such as enzyme linked immunosorbent assay, high performance liquid chromatography, and thin layer chromatography. The authors hope that high precision and low detection limit spectrum instrument, and software technology and calibration model of mycotoxins determination, will fast measure accurately the quality and quantity of mycotoxins, which will provide basis for reasonable process and utilization of forage and promote the application of NIRS in the safety livestock product.

Multivariate analysis of nystatin and metronidazole in a semi-solid matrix by means of diffuse reflectance NIR spectroscopy and PLS regression.

PubMed

Baratieri, Sabrina C; Barbosa, Juliana M; Freitas, Matheus P; Martins, José A

2006-01-23

A multivariate method of analysis of nystatin and metronidazole in a semi-solid matrix, based on diffuse reflectance NIR measurements and partial least squares regression, is reported. The product, a vaginal cream used in the antifungal and antibacterial treatment, is usually, quantitatively analyzed through microbiological tests (nystatin) and HPLC technique (metronidazole), according to pharmacopeial procedures. However, near infrared spectroscopy has demonstrated to be a valuable tool for content determination, given the rapidity and scope of the method. In the present study, it was successfully applied in the prediction of nystatin (even in low concentrations, ca. 0.3-0.4%, w/w, which is around 100,000 IU/5g) and metronidazole contents, as demonstrated by some figures of merit, namely linearity, precision (mean and repeatability) and accuracy.

Analysis of silage composition by near-infrared reflectance spectroscopy

NASA Astrophysics Data System (ADS)

Reeves, James B., III; Blosser, Timothy H.; Colenbrander, V. F.

1991-02-01

Two studies were performed to investigate the feasibility of using near infrared reflectance spectroscopy (NIRS) with undried silages. In the first study silages were analyzed for major components (e. g. dry matter crude protein and other forms of nitrogen fiber and in vitro digestible dry matter) and short chain fatty acids (SCFA). NIRS was found to operate satisfactorily except for some forms of nitrogen and SCFA. In study two various methods of grinding spectral regions and sample presentation were examined. Undried Wiley ground samples in a rectangular cell gave the best overall results for non-dry ice undried grinds with wavelengths between 1100 and 2498 nm. Silages scanned after drying however produced the best results. Intact samples did not perform as well as ground samples and wavelengths below 1100 nm were of little use. 2 .

Lack of irrefutable validation does not negate clinical utility of near-infrared spectroscopy monitoring: learning to trust new technology.

PubMed

Kane, Jason M; Steinhorn, David M

2009-09-01

Reliance on new monitoring device technology is based upon an understanding of how the device operates and its reliability in a specific clinical setting. The introduction of new monitoring devices will therefore elicit either distrust of the new technology and the data presented or adoption of new devices. The use of near-infrared spectroscopy (NIRS) technology to monitor vital organs in postoperative pediatric cardiac surgery patients has been extensively described yet controversy remains as to the use of this monitoring device. The following retrospective case series demonstrates how learning from trends in data elicited from 2-site NIRS monitoring provided important bedside insights. These insights led to changes in clinician behavior and reliance on NIRS monitoring for early recognition of clinically silent deteriorations. Disregard for the NIRS data may have led to a fatal outcome in an unstable patient who might have received more timely intervention if the NIRS data had been acknowledged earlier. This case series demonstrates that 2-site NIRS monitoring accurately reflects situations in which poor clinical outcomes may occur when declining trends in somatic tissue oxygen saturations are not corrected. Physician management of the postoperative pediatric cardiac surgery patient can change based upon the insights gained through the application of NIRS monitoring.

Examination of U valence states in the brannerite structure by near-infrared diffuse reflectance and X-ray photoelectron spectroscopies

NASA Astrophysics Data System (ADS)

Finnie, Kim S.; Zhang, Zhaoming; Vance, Eric R.; Carter, Melody L.

2003-04-01

The valence state of uranium doped into a f 0 thorium analog of brannerite (i.e., thorutite) has been examined using near-infrared (NIR) diffuse reflectance (DRS) and X-ray photoelectron (XPS) spectroscopies. NIR transitions of U 4+, which are not observed in spectra of brannerite, have been detected in the samples of U xTh 1- xTi 2O 6, and we propose that strong specular reflectance is responsible for the lack of U 4+ features in UTi 2O 6. Characteristic U 5+ bands have been identified in samples in which sufficient Ca 2+ has been added to nominally effect complete oxidation to U 5+. XPS results support the assignments of U 4+ and U 5+ by DRS. The presence of residual U 4+ bands in the spectra of the Ca-doped samples is consistent with segregation of Ca 2+ to the grain boundaries during high temperature sintering.

Near-infrared reflectance spectroscopy (NIRS) for rapid determination of ginsenoside Rg1 and Re in Chinese patent medicine Naosaitong pill

NASA Astrophysics Data System (ADS)

Zhang, Wei; Qu, Zhengyi; Wang, Yingping; Yao, Chunlin; Bai, Xueyuan; Bian, Shuai; Zhao, Bing

2015-03-01

Ginsenosides in plant samples have been extensively studied because protopanaxadiol saponins are ubiquitous in Chinese patent medicines, in which they can be used in promoting human health as the main active ingredients. A method for rapid determination of two ginsenosides (Rg1 and Re) in Naosaitong (NST) samples using near-infrared reflectance spectroscopy (NIRS) is studied to determine the contents of ginsenoside Rg1 and Re in this work. Partial least square (PLS) regression was used for building the calibration models, and the effects of spectral preprocessing and variable selection on the models are investigated for optimization of the models. A total of 93 samples were scanned by NIRS, and also by high performance liquid chromatography coupled to a diode array detector to determine the contents of ginsenoside Rg1 and Re. The calibration models for Rg1 and Re had high values of the coefficient of determination (R2) (0.9766 and 0.9764) and low root mean square error of cross validation (RMSECV) (0.0136 and 0.0104), and the values of the standard error of prediction set (SEP) are 0.00764 and 0.0103, which indicate a good correlation between reference values and NIRS predicted values. The overall results show that NIRS could be applied for the rapid determination of the contents of ginsenosides in Ginseng byproducts for pharmaceuticals that develop high-quality Chinese patent medicines.

Rapid identification of oil-contaminated soils using visible near-infrared diffuse reflectance spectroscopy.

PubMed

Chakraborty, Somsubhra; Weindorf, David C; Morgan, Cristine L S; Ge, Yufeng; Galbraith, John M; Li, Bin; Kahlon, Charanjit S

2010-01-01

In the United States, petroleum extraction, refinement, and transportation present countless opportunities for spillage mishaps. A method for rapid field appraisal and mapping of petroleum hydrocarbon-contaminated soils for environmental cleanup purposes would be useful. Visible near-infrared (VisNIR, 350-2500 nm) diffuse reflectance spectroscopy (DRS) is a rapid, nondestructive, proximal-sensing technique that has proven adept at quantifying soil properties in situ. The objective of this study was to determine the prediction accuracy of VisNIR DRS in quantifying petroleum hydrocarbons in contaminated soils. Forty-six soil samples (including both contaminated and reference samples) were collected from six different parishes in Louisiana. Each soil sample was scanned using VisNIR DRS at three combinations of moisture content and pretreatment: (i) field-moist intact aggregates, (ii) air-dried intact aggregates, (iii) and air-dried ground soil (sieved through a 2-mm sieve). The VisNIR spectra of soil samples were used to predict total petroleum hydrocarbon (TPH) content in the soil using partial least squares (PLS) regression and boosted regression tree (BRT) models. Each model was validated with 30% of the samples that were randomly selected and not used in the calibration model. The field-moist intact scan proved best for predicting TPH content with a validation r2 of 0.64 and relative percent difference (RPD) of 1.70. Because VisNIR DRS was promising for rapidly predicting soil petroleum hydrocarbon content, future research is warranted to evaluate the methodology for identifying petroleum contaminated soils.

Identification of cattle, llama and horse meat by near infrared reflectance or transflectance spectroscopy.

PubMed

Mamani-Linares, L W; Gallo, C; Alomar, D

2012-02-01

Visible and near infrared reflectance spectroscopy (VIS-NIRS) was used to discriminate meat and meat juices from three livestock species. In a first trial, samples of Longissimus lumborum muscle, corresponding to beef (31) llamas (21) and horses (27), were homogenised and their spectra collected in reflectance (NIRSystems 6500 scanning monochromator, in the range of 400-2500 nm). In the second trial, samples of meat juice (same muscle) from the same species (20 beef, 19 llama and 19 horse) were scanned in folded transmission (transflectance). Discriminating models (PLS regression) were developed against "dummy" variables, testing different mathematical treatments of the spectra. Best models indentified the species of almost all samples by their meat (reflectance) or meat juice (transflectance) spectra. A few (three of beef and one of llama, for meat samples; one of beef and one of horse, for juice samples) were classified as uncertain. It is concluded that NIRS is an effective tool to recognise meat and meat juice from beef, llama and horses. Copyright © 2011 Elsevier Ltd. All rights reserved.

Real-time soil sensing based on fiber optics and spectroscopy

NASA Astrophysics Data System (ADS)

Li, Minzan

2005-08-01

Using NIR spectroscopic techniques, correlation analysis and regression analysis for soil parameter estimation was conducted with raw soil samples collected in a cornfield and a forage field. Soil parameters analyzed were soil moisture, soil organic matter, nitrate nitrogen, soil electrical conductivity and pH. Results showed that all soil parameters could be evaluated by NIR spectral reflectance. For soil moisture, a linear regression model was available at low moisture contents below 30 % db, while an exponential model can be used in a wide range of moisture content up to 100 % db. Nitrate nitrogen estimation required a multi-spectral exponential model and electrical conductivity could be evaluated by a single spectral regression. According to the result above mentioned, a real time soil sensor system based on fiber optics and spectroscopy was developed. The sensor system was composed of a soil subsoiler with four optical fiber probes, a spectrometer, and a control unit. Two optical fiber probes were used for illumination and the other two optical fiber probes for collecting soil reflectance from visible to NIR wavebands at depths around 30 cm. The spectrometer was used to obtain the spectra of reflected lights. The control unit consisted of a data logging device, a personal computer, and a pulse generator. The experiment showed that clear photo-spectral reflectance was obtained from the underground soil. The soil reflectance was equal to that obtained by the desktop spectrophotometer in laboratory tests. Using the spectral reflectance, the soil parameters, such as soil moisture, pH, EC and SOM, were evaluated.

Quantitative analysis of bayberry juice acidity based on visible and near-infrared spectroscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shao Yongni; He Yong; Mao Jingyuan

Visible and near-infrared (Vis/NIR) reflectance spectroscopy has been investigated for its ability to nondestructively detect acidity in bayberry juice. What we believe to be a new, better mathematic model is put forward, which we have named principal component analysis-stepwise regression analysis-backpropagation neural network (PCA-SRA-BPNN), to build a correlation between the spectral reflectivity data and the acidity of bayberry juice. In this model, the optimum network parameters,such as the number of input nodes, hidden nodes, learning rate, and momentum, are chosen by the value of root-mean-square (rms) error. The results show that its prediction statistical parameters are correlation coefficient (r) ofmore » 0.9451 and root-mean-square error of prediction(RMSEP) of 0.1168. Partial least-squares (PLS) regression is also established to compare with this model. Before doing this, the influences of various spectral pretreatments (standard normal variate, multiplicative scatter correction, S. Golay first derivative, and wavelet package transform) are compared. The PLS approach with wavelet package transform preprocessing spectra is found to provide the best results, and its prediction statistical parameters are correlation coefficient (r) of 0.9061 and RMSEP of 0.1564. Hence, these two models are both desirable to analyze the data from Vis/NIR spectroscopy and to solve the problem of the acidity prediction of bayberry juice. This supplies basal research to ultimately realize the online measurements of the juice's internal quality through this Vis/NIR spectroscopy technique.« less

Measurement of sugar content of watermelon using near-infrared reflectance spectroscopy in comparison with dielectric property

NASA Astrophysics Data System (ADS)

Tao, Xuemei; Bao, Yidan

2006-09-01

The sugar content of watermelon is important to its taste thus influences the market. It's difficult to know whether the melon is sweet or not for consumers. We tried to develop a convenient meter to determine the sugar of watermelon. The first objective of this paper was to demonstrate the feasibility of using a near-infrared reflectance spectrometer (NIRS) to investigate the relationship between sugar content of watermelon and absorption spectra. The NIRS reflectance of nondestructive watermelon was measured with a Visible/NIR spectrophotometer in 325-1075nm range. The sugar content of watermelon was obtained with a handhold sugar content meter. The second objective was to measure the watermelon's dielectric property, such as dielectric resistance, capacitance, quality factor and dielectric loss. A digital electric bridge instrument was used to get the dielectric property. The experimental results show that they were related to watermelon's sugar content. A comparison between the two methods was made in the paper. The model derived from NIRS reflection is useful for class identification of Zaochun Hongyu watermelon though it's not quite accurate in sweetness prediction (the max. deviation is 0.7). Electric property bears little relation to sugar content of watermelon at this experiment and it couldn't be used as non-destructive inspection method.

Nondestructive estimation of wood chemical composition of sections of radial wood strips by diffuse reflectance near infrared spectroscopy

Treesearch

P. David Jones; Laurence R. Schimleck; Gary F. Peter; Richard F. Daniels; Alexander Clark

2006-01-01

The use of calibrated near infrared (NIR) spectroscopy for predicting the chemical composition of Pirus taeda L. (loblolly pine) wood samples is investigated. Seventeen P. taeda radial strips, representing seven different sites were selected and NlR spectra were obtained from the radial longitudinal face of each strip. The spectra...

Analysis of multiple soybean phytonutrients by near-infrared reflectance spectroscopy.

PubMed

Zhang, Gaoyang; Li, Penghui; Zhang, Wenfei; Zhao, Jian

2017-05-01

Improvement of the nutritional quality of soybean is usually facilitated by a vast range of soybean germplasm with enough information about their multiple phytonutrients. In order to acquire this essential information from a huge number of soybean samples, a rapid analytic method is urgently required. Here, a nondestructive near-infrared reflectance spectroscopy (NIRS) method was developed for rapid and accurate measurement of 25 nutritional components in soybean simultaneously, including fatty acids palmitic acid, stearic acid, oleic acid, linoleic acid, and linolenic acid, vitamin E (VE), α-VE, γ-VE, δ-VE, saponins, isoflavonoids, and flavonoids. Modified partial least squares regression and first, second, third, and fourth derivative transformation was applied for the model development. The 1 minus variance ratio (1-VR) value of the optimal model can reach between the highest 0.95 and lowest 0.64. The predicted values of phytonutrients in soybean using NIRS technology are comparable to those obtained from using the traditional spectrum or chemical methods. A robust NIRS can be adopted as a reliable method to evaluate complex plant constituents for screening large-scale samples of soybean germplasm resources or genetic populations for improvement of nutritional qualities. Graphical Abstract ᅟ.

Noncontact analysis of the fiber weight per unit area in prepreg by near-infrared spectroscopy.

PubMed

Jiang, B; Huang, Y D

2008-05-26

The fiber weight per unit area in prepreg is an important factor to ensure the quality of the composite products. Near-infrared spectroscopy (NIRS) technology together with a noncontact reflectance sources has been applied for quality analysis of the fiber weight per unit area. The range of the unit area fiber weight was 13.39-14.14mgcm(-2). The regression method was employed by partial least squares (PLS) and principal components regression (PCR). The calibration model was developed by 55 samples to determine the fiber weight per unit area in prepreg. The determination coefficient (R(2)), root mean square error of calibration (RMSEC) and root mean square error of prediction (RMSEP) were 0.82, 0.092, 0.099, respectively. The predicted values of the fiber weight per unit area in prepreg measured by NIRS technology were comparable to the values obtained by the reference method. For this technology, the noncontact reflectance sources focused directly on the sample with neither previous treatment nor manipulation. The results of the paired t-test revealed that there was no significant difference between the NIR method and the reference method. Besides, the prepreg could be analyzed one time within 20s without sample destruction.

Validation of brain-derived signals in near-infrared spectroscopy through multivoxel analysis of concurrent functional magnetic resonance imaging.

PubMed

Moriguchi, Yoshiya; Noda, Takamasa; Nakayashiki, Kosei; Takata, Yohei; Setoyama, Shiori; Kawasaki, Shingo; Kunisato, Yoshihiko; Mishima, Kazuo; Nakagome, Kazuyuki; Hanakawa, Takashi

2017-10-01

Near-infrared spectroscopy (NIRS) is a convenient and safe brain-mapping tool. However, its inevitable confounding with hemodynamic responses outside the brain, especially in the frontotemporal head, has questioned its validity. Some researchers attempted to validate NIRS signals through concurrent measurements with functional magnetic resonance imaging (fMRI), but, counterintuitively, NIRS signals rarely correlate with local fMRI signals in NIRS channels, although both mapping techniques should measure the same hemoglobin concentration. Here, we tested a novel hypothesis that different voxels within the scalp and the brain tissues might have substantially different hemoglobin absorption rates of near-infrared light, which might differentially contribute to NIRS signals across channels. Therefore, we newly applied a multivariate approach, a partial least squares regression, to explain NIRS signals with multivoxel information from fMRI within the brain and soft tissues in the head. We concurrently obtained fMRI and NIRS signals in 9 healthy human subjects engaging in an n-back task. The multivariate fMRI model was quite successfully able to predict the NIRS signals by cross-validation (interclass correlation coefficient = ∼0.85). This result confirmed that fMRI and NIRS surely measure the same hemoglobin concentration. Additional application of Monte-Carlo permutation tests confirmed that the model surely reflects temporal and spatial hemodynamic information, not random noise. After this thorough validation, we calculated the ratios of the contributions of the brain and soft-tissue hemodynamics to the NIRS signals, and found that the contribution ratios were quite different across different NIRS channels in reality, presumably because of the structural complexity of the frontotemporal regions. Hum Brain Mapp 38:5274-5291, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Predicting Soil Salinity with Vis–NIR Spectra after Removing the Effects of Soil Moisture Using External Parameter Orthogonalization

PubMed Central

Liu, Ya; Pan, Xianzhang; Wang, Changkun; Li, Yanli; Shi, Rongjie

2015-01-01

Robust models for predicting soil salinity that use visible and near-infrared (vis–NIR) reflectance spectroscopy are needed to better quantify soil salinity in agricultural fields. Currently available models are not sufficiently robust for variable soil moisture contents. Thus, we used external parameter orthogonalization (EPO), which effectively projects spectra onto the subspace orthogonal to unwanted variation, to remove the variations caused by an external factor, e.g., the influences of soil moisture on spectral reflectance. In this study, 570 spectra between 380 and 2400 nm were obtained from soils with various soil moisture contents and salt concentrations in the laboratory; 3 soil types × 10 salt concentrations × 19 soil moisture levels were used. To examine the effectiveness of EPO, we compared the partial least squares regression (PLSR) results established from spectra with and without EPO correction. The EPO method effectively removed the effects of moisture, and the accuracy and robustness of the soil salt contents (SSCs) prediction model, which was built using the EPO-corrected spectra under various soil moisture conditions, were significantly improved relative to the spectra without EPO correction. This study contributes to the removal of soil moisture effects from soil salinity estimations when using vis–NIR reflectance spectroscopy and can assist others in quantifying soil salinity in the future. PMID:26468645

Univariate and multivariate analysis of tannin-impregnated wood species using vibrational spectroscopy.

PubMed

Schnabel, Thomas; Musso, Maurizio; Tondi, Gianluca

2014-01-01

Vibrational spectroscopy is one of the most powerful tools in polymer science. Three main techniques--Fourier transform infrared spectroscopy (FT-IR), FT-Raman spectroscopy, and FT near-infrared (NIR) spectroscopy--can also be applied to wood science. Here, these three techniques were used to investigate the chemical modification occurring in wood after impregnation with tannin-hexamine preservatives. These spectroscopic techniques have the capacity to detect the externally added tannin. FT-IR has very strong sensitivity to the aromatic peak at around 1610 cm(-1) in the tannin-treated samples, whereas FT-Raman reflects the peak at around 1600 cm(-1) for the externally added tannin. This high efficacy in distinguishing chemical features was demonstrated in univariate analysis and confirmed via cluster analysis. Conversely, the results of the NIR measurements show noticeable sensitivity for small differences. For this technique, multivariate analysis is required and with this chemometric tool, it is also possible to predict the concentration of tannin on the surface.

Integrated Mueller-matrix near-infrared imaging and point-wise spectroscopy improves colonic cancer detection

PubMed Central

Wang, Jianfeng; Zheng, Wei; Lin, Kan; Huang, Zhiwei

2016-01-01

We report the development and implementation of a unique integrated Mueller-matrix (MM) near-infrared (NIR) imaging and Mueller-matrix point-wise diffuse reflectance (DR) spectroscopy technique for improving colonic cancer detection and diagnosis. Point-wise MM DR spectra can be acquired from any suspicious tissue areas indicated by MM imaging. A total of 30 paired colonic tissue specimens (normal vs. cancer) were measured using the integrated MM imaging and point-wise MM DR spectroscopy system. Polar decomposition algorithms are employed on the acquired images and spectra to derive three polarization metrics including depolarization, diattentuation and retardance for colonic tissue characterization. The decomposition results show that tissue depolarization and retardance are significantly decreased (p<0.001, paired 2-sided Student’s t-test, n = 30); while the tissue diattentuation is significantly increased (p<0.001, paired 2-sided Student’s t-test, n = 30) associated with colonic cancer. Further partial least squares discriminant analysis (PLS-DA) and leave-one tissue site-out, cross validation (LOSCV) show that the combination of the three polarization metrics provide the best diagnostic accuracy of 95.0% (sensitivity: 93.3%, and specificity: 96.7%) compared to either of the three polarization metrics (sensitivities of 93.3%, 83.3%, and 80.0%; and specificities of 90.0%, 96.7%, and 80.0%, respectively, for the depolarization, diattentuation and retardance metrics) for colonic cancer detection. This work suggests that the integrated MM NIR imaging and point-wise MM NIR diffuse reflectance spectroscopy has the potential to improve the early detection and diagnosis of malignant lesions in the colon. PMID:27446640

Detection of urinary estrogen conjugates and creatinine using near infrared spectroscopy in Bornean orangutans (Pongo Pygmaeus).

PubMed

Kinoshita, Kodzue; Kuze, Noko; Kobayashi, Toshio; Miyakawa, Etsuko; Narita, Hiromitsu; Inoue-Murayama, Miho; Idani, Gen'ichi; Tsenkova, Roumiana

2016-01-01

For promoting in situ conservation, it is important to estimate the density distribution of fertile individuals, and there is a need for developing an easy monitoring method to discriminate between physiological states. To date, physiological state has generally been determined by measuring hormone concentration using radioimmunoassay or enzyme immunoassay (EIA) methods. However, these methods have rarely been applied in situ because of the requirements for a large amount of reagent, instruments, and a radioactive isotope. In addition, the proper storage of the sample (including urine and feces) on site until analysis is difficult. On the other hand, near infrared (NIR) spectroscopy requires no reagent and enables rapid measurement. In the present study, we attempted urinary NIR spectroscopy to determine the estrogen levels of orangutans in Japanese zoos and in the Danum Valley Conservation Area, Sabah, Malaysia. Reflectance NIR spectra were obtained from urine stored using a filter paper. Filter paper is easy to use to store dried urine, even in the wild. Urinary estrogen and creatinine concentrations measured by EIA were used as the reference data of partial least square (PLS) regression of urinary NIR spectra. High accuracies (R(2) > 0.68) were obtained in both estrogen and creatinine regression models. In addition, the PLS regressions in both standards showed higher accuracies (R(2) > 0.70). Therefore, the present study demonstrates that urinary NIR spectra have the potential to estimate the estrogen and creatinine concentrations.

Near infrared spectroscopy and chemometrics analysis of complex traits in animal physiology

USDA-ARS?s Scientific Manuscript database

Near infrared reflectance (NIR) applications have been expanding from the traditional framework of small molecule chemical purity and composition (as defined by spectral libraries) to complex system analysis and holistic exploratory approaches to questions in biochemistry, biophysics and environment...

Diffuse Reflectance Spectroscopy of Hidden Objects, Part I: Interpretation of the Reflection-Absorption-Scattering Fractions in Near-Infrared (NIR) Spectra of Polyethylene Films.

PubMed

Pomerantsev, Alexey L; Rodionova, Oxana Ye; Skvortsov, Alexej N

2017-08-01

Investigation of a sample covered by an interfering layer is required in many fields, e.g., for process control, biochemical analysis, and many other applications. This study is based on the analysis of spectra collected by near-infrared (NIR) diffuse reflectance spectroscopy. Each spectrum is a composition of a useful, target spectrum and a spectrum of an interfering layer. To recover the target spectrum, we suggest using a new phenomenological approach, which employs the multivariate curve resolution (MCR) method. In general terms, the problem is very complex. We start with a specific problem of analyzing a system, which consists of several layers of polyethylene (PE) film and underlayer samples with known spectral properties. To separate information originating from PE layers and the target, we modify the system versus both the number of the PE layers as well as the reflectance properties of the target sample. We consider that the interfering spectrum of the layer can be modeled using three components, which can be tentatively called transmission, absorption, and scattering contributions. The novelty of our approach is that we do not remove the reflectance and scattering effects from the spectra, but study them in detail aiming to use this information to recover the target spectrum.

Near-infrared reflectance spectroscopy calibrations for assessment of oil, phenols, glucosinolates and fatty acid content in the intact seeds of oilseed Brassica species.

PubMed

Sen, Rahul; Sharma, Sanjula; Kaur, Gurpreet; Banga, Surinder S

2018-01-31

Very few near-infrared reflectance spectroscopy (NIRS) calibration models are available for non-destructive estimation of seed quality traits in Brassica juncea. Those that are available also fail to adequately discern variation for oleic acid (C 18:1 ) , linolenic (C 18:3 ) fatty acids, meal glucosinolates and phenols. We report the development of a new NIRS calibration equation that is expected to fill the gaps in the existing NIRS equations. Calibrations were based on the reference values of important quality traits estimated from a purposely selected germplasm set comprising 240 genotypes of B. juncea and 193 of B. napus. We were able to develop optimal NIRS-based calibration models for oil, phenols, glucosinolates, oleic acid, linoleic acid and erucic acid for B. juncea and B. napus. Correlation coefficients (RSQ) of the external validations appeared greater than 0.7 for the majority of traits, such as oil (0.766, 0.865), phenols (0.821, 0.915), glucosinolates (0.951, 0.986), oleic acid (0.814. 0.810), linoleic acid (0.974, 0.781) and erucic acid (0.963, 0.943) for B. juncea and B. napus, respectively. The results demonstrate the robust predictive power of the developed calibration models for rapid estimation of many quality traits in intact rapeseed-mustard seeds which will assist plant breeders in effective screening and selection of lines in quality improvement breeding programmes. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

Early pregnancy diagnosis in sheep using near-infrared spectroscopy on blood plasma.

PubMed

Andueza, Donato; Alabart, José L; Lahoz, Belén; Muñoz, Fernando; Folch, José

2014-02-01

The objective of this study was to evaluate the ability of near-infrared reflectance spectroscopy (NIRS) to discriminate between pregnant and nonpregnant ewes in early stages of pregnancy after artificial insemination (AI) from blood plasma. Samples were collected using jugular puncture at 18 and 25 days after AI from 188 Rasa Aragonesa and Ansotana ewes. Plasma samples were analyzed for pregnancy-associated glycoprotein (PAG) and progesterone (P4) using ELISA commercial kits. The spectra of plasma samples were recorded in the visible and near-infrared ranges. The performance of these tests were compared, using as criterion standard the pregnancy status determined using transabdominal ultrasonography at 45 days after AI. Pregnancy rate was 47.9% (90/188). At Day 18, sensitivity was similar in NIRS and P4 tests (98.9% vs. 100%; not significant) and greater than PAG (32.2%; both P < 0.001). Specificity was similar in NIRS and PAG tests (both 100%) and greater than that of P4 (84.7%; P < 0.001). At Day 25, sensitivity and specificity of NIRS and PAG were both 100%. It can be concluded that NIRS was an accurate method of diagnosis of pregnancy at Days 18 and 25 after AI in ewes. Copyright © 2014 Elsevier Inc. All rights reserved.

Discovery of the linear region of Near Infrared Diffuse Reflectance spectra using the Kubelka-Munk theory

NASA Astrophysics Data System (ADS)

Dai, Shengyun; Pan, Xiaoning; Ma, Lijuan; Huang, Xingguo; Du, Chenzhao; Qiao, Yanjiang; Wu, Zhisheng

2018-05-01

Particle size is of great importance for the quantitative model of the NIR diffuse reflectance. In this paper, the effect of sample particle size on the measurement of harpagoside in Radix Scrophulariae powder by near infrared diffuse (NIR) reflectance spectroscopy was explored. High-performance liquid chromatography (HPLC) was employed as a reference method to construct the quantitative particle size model. Several spectral preprocessing methods were compared, and particle size models obtained by different preprocessing methods for establishing the partial least-squares (PLS) models of harpagoside. Data showed that the particle size distribution of 125-150 μm for Radix Scrophulariae exhibited the best prediction ability with R2pre=0.9513, RMSEP=0.1029 mg·g-1, and RPD = 4.78. For the hybrid granularity calibration model, the particle size distribution of 90-180 μm exhibited the best prediction ability with R2pre=0.8919, RMSEP=0.1632 mg·g-1, and RPD = 3.09. Furthermore, the Kubelka-Munk theory was used to relate the absorption coefficient k (concentration-dependent) and scatter coefficient s (particle size-dependent). The scatter coefficient s was calculated based on the Kubelka-Munk theory to study the changes of s after being mathematically preprocessed. A linear relationship was observed between k/s and absorption A within a certain range and the value for k/s was greater than 4. According to this relationship, the model was more accurately constructed with the particle size distribution of 90-180 μm when s was kept constant or in a small linear region. This region provided a good reference for the linear modeling of diffuse reflectance spectroscopy. To establish a diffuse reflectance NIR model, further accurate assessment should be obtained in advance for a precise linear model.

Rapid biochemical methane potential prediction of urban organic waste with near-infrared reflectance spectroscopy.

PubMed

Fitamo, T; Triolo, J M; Boldrin, A; Scheutz, C

2017-08-01

The anaerobic digestibility of various biomass feedstocks in biogas plants is determined with biochemical methane potential (BMP) assays. However, experimental BMP analysis is time-consuming, costly and challenging to optimise stock management and feeding to achieve improved biogas production. The aim of the present study is to develop a fast and reliable model based on near-infrared reflectance spectroscopy (NIRS) for the BMP prediction of urban organic waste (UOW). The model comprised 87 UOW samples. Additionally, 88 plant biomass samples were included, to develop a combined model predicting BMP. The coefficient of determination (R 2 ) and root mean square error in prediction (RMSE P ) of the UOW model were 0.88 and 44 mL CH 4 /g VS, while the combined model was 0.89 and 50 mL CH 4 /g VS. Improved model performance was obtained for the two individual models compared to the combined version. The BMP prediction with NIRS was satisfactory and moderately successful. Copyright © 2017 Elsevier Ltd. All rights reserved.

A non-destructive spectroscopic study of the decoration of archaeological pottery: from matt-painted bichrome ceramic sherds (southern Italy, VIII-VII B.C.) to an intact Etruscan cinerary urn

NASA Astrophysics Data System (ADS)

Bruni, Silvia; Guglielmi, Vittoria; Della Foglia, Elena; Castoldi, Marina; Bagnasco Gianni, Giovanna

2018-02-01

A study is presented based on the use of entirely non-destructive spectroscopic techniques to analyze the chemical composition of the painted surface layer of archaeological pottery. This study aims to define both the raw materials and the working technology of ancient potters. Energy-dispersive X-ray analysis, micro-Raman spectroscopy, visible and near infrared (NIR) diffuse reflection spectroscopy and external reflection Fourier-transform infrared (FTIR) spectroscopy were applied to matt-painted bichrome pottery sherds (VIII-VII century B.C.) from the site of Incoronata near Metaponto in southern Italy. Two different raw materials, ochre and iron-rich clay, were recognized for the red decoration, while the dark areas resulted to have been obtained by the so-called manganese black technique. In any case, it was demonstrated that the decoration was applied before firing, in spite of its sometimes grainy aspect that could suggest a post-firing application. For the samples with a more sophisticated decorative pattern a red/black/white polychromy was recognized, as the lighter areas correspond to an ;intentional white; obtained by the firing of a calcium-rich clay. Reflection spectroscopy in the visible-NIR and mid-IR as well as micro-Raman spectroscopy were then employed to characterize the decoration of an intact ceramic urn from the Etruscan town of Chiusi, evidencing a post-firing painting based on the use of red ochre, carbon black and lime, possibly imitating the ;fresco; technique used in wall paintings.

Component Analysis and Identification of Black Tahitian Cultured Pearls From the Oyster Pinctada margaritifera Using Spectroscopic Techniques

NASA Astrophysics Data System (ADS)

Shi, L.; Wang, Y.; Liu, X.; Mao, J.

2018-03-01

Raman spectroscopy, ultraviolet, visible, and near infrared (UV-Vis-NIR) reflectance spectroscopy, and X-ray fluorescence (XRF) spectroscopy were used to characterize black Tahitian cultured pearls and imitations of these saltwater cultured pearls produced by γ-irradiation, and by coloring of cultured pearls with silver nitrate or organic dyes. Raman spectra indicated that aragonite was the major constituent of these four types of pearl. Using Raman spectroscopy at an excitation wavelength of 514 nm, black Tahitian cultured pearls exhibited characteristic 1100-1700 cm-1 bands. These bands were attributed to various organic components, including conchiolin and other black biological pigments. The peaks shown by saltwater cultured pearls colored with organic dyes varied with the type of dye used. Tahitian cultured and organic-dye-treated saltwater cultured pearls were easily identified by Raman spectroscopy. UV-Vis-NIR reflectance spectra showed bands at 408, 497, and 700 nm derived from porphyrin pigment and other black pigments. The spectra of dye-treated black saltwater pearls showed absorption peaks at 216, 261, 300, and 578 nm. The 261-nm absorption band disappeared from the spectra of γ-irradiated saltwater cultured pearls. This suggests the degradation of conchiolin in the γ-irradiated saltwater cultured pearls. XRF analysis revealed the presence of Ag on the surface of silver nitrate-dyed saltwater cultured pearls.

Rapid estimation of nutritional elements on citrus leaves by near infrared reflectance spectroscopy.

PubMed

Galvez-Sola, Luis; García-Sánchez, Francisco; Pérez-Pérez, Juan G; Gimeno, Vicente; Navarro, Josefa M; Moral, Raul; Martínez-Nicolás, Juan J; Nieves, Manuel

2015-01-01

Sufficient nutrient application is one of the most important factors in producing quality citrus fruits. One of the main guides in planning citrus fertilizer programs is by directly monitoring the plant nutrient content. However, this requires analysis of a large number of leaf samples using expensive and time-consuming chemical techniques. Over the last 5 years, it has been demonstrated that it is possible to quantitatively estimate certain nutritional elements in citrus leaves by using the spectral reflectance values, obtained by using near infrared reflectance spectroscopy (NIRS). This technique is rapid, non-destructive, cost-effective and environmentally friendly. Therefore, the estimation of macro and micronutrients in citrus leaves by this method would be beneficial in identifying the mineral status of the trees. However, to be used effectively NIRS must be evaluated against the standard techniques across different cultivars. In this study, NIRS spectral analysis, and subsequent nutrient estimations for N, K, Ca, Mg, B, Fe, Cu, Mn, and Zn concentration, were performed using 217 leaf samples from different citrus trees species. Partial least square regression and different pre-processing signal treatments were used to generate the best estimation against the current best practice techniques. It was verified a high proficiency in the estimation of N (Rv = 0.99) and Ca (Rv = 0.98) as well as achieving acceptable estimation for K, Mg, Fe, and Zn. However, no successful calibrations were obtained for the estimation of B, Cu, and Mn.

Rapid estimation of nutritional elements on citrus leaves by near infrared reflectance spectroscopy

PubMed Central

Galvez-Sola, Luis; García-Sánchez, Francisco; Pérez-Pérez, Juan G.; Gimeno, Vicente; Navarro, Josefa M.; Moral, Raul; Martínez-Nicolás, Juan J.; Nieves, Manuel

2015-01-01

Sufficient nutrient application is one of the most important factors in producing quality citrus fruits. One of the main guides in planning citrus fertilizer programs is by directly monitoring the plant nutrient content. However, this requires analysis of a large number of leaf samples using expensive and time-consuming chemical techniques. Over the last 5 years, it has been demonstrated that it is possible to quantitatively estimate certain nutritional elements in citrus leaves by using the spectral reflectance values, obtained by using near infrared reflectance spectroscopy (NIRS). This technique is rapid, non-destructive, cost-effective and environmentally friendly. Therefore, the estimation of macro and micronutrients in citrus leaves by this method would be beneficial in identifying the mineral status of the trees. However, to be used effectively NIRS must be evaluated against the standard techniques across different cultivars. In this study, NIRS spectral analysis, and subsequent nutrient estimations for N, K, Ca, Mg, B, Fe, Cu, Mn, and Zn concentration, were performed using 217 leaf samples from different citrus trees species. Partial least square regression and different pre-processing signal treatments were used to generate the best estimation against the current best practice techniques. It was verified a high proficiency in the estimation of N (Rv = 0.99) and Ca (Rv = 0.98) as well as achieving acceptable estimation for K, Mg, Fe, and Zn. However, no successful calibrations were obtained for the estimation of B, Cu, and Mn. PMID:26257767

Near infrared reflectance spectroscopy studies of Chinese giant salamanders in aquaculture production

USDA-ARS?s Scientific Manuscript database

NIR spectra were collected at three surface locations for Chinese giant salamanders to ascertain whether spectral signatures could be separated by anatomical, presumably physiologically-based, locations. The first location was the smooth area immediately above the cloaca on the animal’s abdomen, whi...

Profile soil property estimation using a VIS-NIR-EC-force probe

USDA-ARS?s Scientific Manuscript database

Combining data collected in-field from multiple soil sensors has the potential to improve the efficiency and accuracy of soil property estimates. Optical diffuse reflectance spectroscopy (DRS) has been used to estimate many important soil properties, such as soil carbon, water content, and texture. ...

The Detection and Quantification of Adulteration in Ground Roasted Asian Palm Civet Coffee Using Near-Infrared Spectroscopy in Tandem with Chemometrics

NASA Astrophysics Data System (ADS)

Suhandy, D.; Yulia, M.; Ogawa, Y.; Kondo, N.

2018-05-01

In the present research, an evaluation of using near infrared (NIR) spectroscopy in tandem with full spectrum partial least squares (FS-PLS) regression for quantification of degree of adulteration in civet coffee was conducted. A number of 126 ground roasted coffee samples with degree of adulteration 0-51% were prepared. Spectral data were acquired using a NIR spectrometer equipped with an integrating sphere for diffuse reflectance measurement in the range of 1300-2500 nm. The samples were divided into two groups calibration sample set (84 samples) and prediction sample set (42 samples). The calibration model was developed on original spectra using FS-PLS regression with full-cross validation method. The calibration model exhibited the determination coefficient R2=0.96 for calibration and R2=0.92 for validation. The prediction resulted in low root mean square error of prediction (RMSEP) (4.67%) and high ratio prediction to deviation (RPD) (3.75). In conclusion, the degree of adulteration in civet coffee have been quantified successfully by using NIR spectroscopy and FS-PLS regression in a non-destructive, economical, precise, and highly sensitive method, which uses very simple sample preparation.

Cow-specific diet digestibility predictions based on near-infrared reflectance spectroscopy scans of faecal samples.

PubMed

Mehtiö, T; Rinne, M; Nyholm, L; Mäntysaari, P; Sairanen, A; Mäntysaari, E A; Pitkänen, T; Lidauer, M H

2016-04-01

This study was designed to obtain information on prediction of diet digestibility from near-infrared reflectance spectroscopy (NIRS) scans of faecal spot samples from dairy cows at different stages of lactation and to develop a faecal sampling protocol. NIRS was used to predict diet organic matter digestibility (OMD) and indigestible neutral detergent fibre content (iNDF) from faecal samples, and dry matter digestibility (DMD) using iNDF in feed and faecal samples as an internal marker. Acid-insoluble ash (AIA) as an internal digestibility marker was used as a reference method to evaluate the reliability of NIRS predictions. Feed and composite faecal samples were collected from 44 cows at approximately 50, 150 and 250 days in milk (DIM). The estimated standard deviation for cow-specific organic matter digestibility analysed by AIA was 12.3 g/kg, which is small considering that the average was 724 g/kg. The phenotypic correlation between direct faecal OMD prediction by NIRS and OMD by AIA over the lactation was 0.51. The low repeatability and small variability estimates for direct OMD predictions by NIRS were not accurate enough to quantify small differences in OMD between cows. In contrast to OMD, the repeatability estimates for DMD by iNDF and especially for direct faecal iNDF predictions were 0.32 and 0.46, respectively, indicating that developing of NIRS predictions for cow-specific digestibility is possible. A data subset of 20 cows with daily individual faecal samples was used to develop an on-farm sampling protocol. Based on the assessment of correlations between individual sample combinations and composite samples as well as repeatability estimates for individual sample combinations, we found that collecting up to three individual samples yields a representative composite sample. Collection of samples from all the cows of a herd every third month might be a good choice, because it would yield a better accuracy. © 2015 Blackwell Verlag GmbH.

A DAQ-Device-Based Continuous Wave Near-Infrared Spectroscopy System for Measuring Human Functional Brain Activity

PubMed Central

Li, Xiaoli; Liu, Xiaomin

2014-01-01

In the last two decades, functional near-infrared spectroscopy (fNIRS) is getting more and more popular as a neuroimaging technique. The fNIRS instrument can be used to measure local hemodynamic response, which indirectly reflects the functional neural activities in human brain. In this study, an easily implemented way to establish DAQ-device-based fNIRS system was proposed. Basic instrumentation components (light sources driving, signal conditioning, sensors, and optical fiber) of the fNIRS system were described. The digital in-phase and quadrature demodulation method was applied in LabVIEW software to distinguish light sources from different emitters. The effectiveness of the custom-made system was verified by simultaneous measurement with a commercial instrument ETG-4000 during Valsalva maneuver experiment. The light intensity data acquired from two systems were highly correlated for lower wavelength (Pearson's correlation coefficient r = 0.92, P < 0.01) and higher wavelength (r = 0.84, P < 0.01). Further, another mental arithmetic experiment was implemented to detect neural activation in the prefrontal cortex. For 9 participants, significant cerebral activation was detected in 6 subjects (P < 0.05) for oxyhemoglobin and in 8 subjects (P < 0.01) for deoxyhemoglobin. PMID:25180044

Mental fatigue detection based on the functional near infrared spectroscopy

NASA Astrophysics Data System (ADS)

Zhang, Zhen; Xu, Fenggang; Yang, Hanjun; Jiang, Jin; Cao, Yong; Jiao, Xuejun

2017-02-01

Mental fatigue can be induced by long time mental work, mental fatigue caused worse performance and accidents. As a non-invasive technique, functional near-infrared spectroscopy (fNIRS) can measure blood oxygen activity in the cerebral cortex which reflect the cognitive function of brain indirectly. Aiming at investigating whether fNIRS can measure the mental fatigue and study the spatial pattern of hemodynamic response for mental fatigue, we used three sessions of verbal 2-back working memory task for a total of 120 minutes to induce mental fatigue, 15 healthy subjects were recruited and 30 channels including prefrontal cortex (PFC) and motor cortex (MC) were measured by fNIRS. The mean oxyhemoglobin feature for 20s was extracted as well as subjective fatigue level and performance. The results showed significant increase of subjected fatigue level as well as significant decrease performance from session one to three task. With the increased level of fatigue, oxyhemoglobin in PFC increase significantly and the spatial pattern of hemodynamic response in the all 30 channels varied with task duration as well. These findings indicated the potential of fNIRS measured hemodynamic as a mental fatigue indicator.

7 CFR 801.7 - Reference methods and tolerances for near-infrared spectroscopy (NIRS) analyzers.

Code of Federal Regulations, 2013 CFR

2013-01-01

..._of_federal_regulations/ibr_locations.html. (b) Tolerances—(1) NIRS wheat protein analyzers. The... Method 992.23. (3) NIRS corn oil, protein, and starch analyzers. The maintenance tolerances for the NIRS... methods and tolerances for near-infrared spectroscopy (NIRS) analyzers. (a) Reference methods. (1) The...

7 CFR 801.7 - Reference methods and tolerances for near-infrared spectroscopy (NIRS) analyzers.

Code of Federal Regulations, 2011 CFR

2011-01-01

..._of_federal_regulations/ibr_locations.html. (b) Tolerances—(1) NIRS wheat protein analyzers. The... Method 992.23. (3) NIRS corn oil, protein, and starch analyzers. The maintenance tolerances for the NIRS... methods and tolerances for near-infrared spectroscopy (NIRS) analyzers. (a) Reference methods. (1) The...

7 CFR 801.7 - Reference methods and tolerances for near-infrared spectroscopy (NIRS) analyzers.

Code of Federal Regulations, 2014 CFR

2014-01-01

..._of_federal_regulations/ibr_locations.html. (b) Tolerances—(1) NIRS wheat protein analyzers. The... Method 992.23. (3) NIRS corn oil, protein, and starch analyzers. The maintenance tolerances for the NIRS... methods and tolerances for near-infrared spectroscopy (NIRS) analyzers. (a) Reference methods. (1) The...

7 CFR 801.7 - Reference methods and tolerances for near-infrared spectroscopy (NIRS) analyzers.

Code of Federal Regulations, 2012 CFR

2012-01-01

..._of_federal_regulations/ibr_locations.html. (b) Tolerances—(1) NIRS wheat protein analyzers. The... Method 992.23. (3) NIRS corn oil, protein, and starch analyzers. The maintenance tolerances for the NIRS... methods and tolerances for near-infrared spectroscopy (NIRS) analyzers. (a) Reference methods. (1) The...

Mechanical indentation improves cerebral blood oxygenation signal quality of functional near-infrared spectroscopy (fNIRS) during breath holding

NASA Astrophysics Data System (ADS)

Vogt, William C.; Romero, Edwin; LaConte, Stephen M.; Rylander, Christopher G.

2013-03-01

Functional near-infrared spectroscopy (fNIRS) is a well-known technique for non-invasively measuring cerebral blood oxygenation, and many studies have demonstrated that fNIRS signals can be related to cognitive function. However, the fNIRS signal is attenuated by the skin, while scalp blood content has been reported to influence cerebral oxygenation measurements. Mechanical indentation has been shown to increase light transmission through soft tissues by causing interstitial water and blood flow away from the compressed region. To study the effects of indentation on fNIRS, a commercial fNIRS system with 16 emitter/detector pairs was used to measure cerebral blood oxygenation at 2 Hz. This device used diffuse reflectance at 730 nm and 850 nm to calculate deoxy- and oxy-hemoglobin concentrations. A borosilicate glass hemisphere was epoxied over each sensor to function as both an indenter and a lens. After placing the indenter/sensor assembly on the forehead, a pair of plastic bands was placed on top of the fNIRS headband and strapped to the head to provide uniform pressure and tightened to approx. 15 N per strap. Cerebral blood oxygenation was recorded during a breath holding regime (15 second hold, 15 second rest, 6 cycles) in 4 human subjects both with and without the indenter array. Results showed that indentation increased raw signal intensity by 85 +/- 35%, and that indentation increased amplitude of hemoglobin changes during breath cycles by 313% +/- 105%. These results suggest that indentation improves sensing of cerebral blood oxygenation, and may potentially enable sensing of deeper brain tissues.

Matrix Effects in Quantitative Assessment of Pharmaceutical Tablets Using Transmission Raman and Near-Infrared (NIR) Spectroscopy.

PubMed

Sparén, Anders; Hartman, Madeleine; Fransson, Magnus; Johansson, Jonas; Svensson, Olof

2015-05-01

Raman spectroscopy can be an alternative to near-infrared spectroscopy (NIR) for nondestructive quantitative analysis of solid pharmaceutical formulations. Compared with NIR spectra, Raman spectra have much better selectivity, but subsampling was always an issue for quantitative assessment. Raman spectroscopy in transmission mode has reduced this issue, since a large volume of the sample is measured in transmission mode. The sample matrix, such as particle size of the drug substance in a tablet, may affect the Raman signal. In this work, matrix effects in transmission NIR and Raman spectroscopy were systematically investigated for a solid pharmaceutical formulation. Tablets were manufactured according to an experimental design, varying the factors particle size of the drug substance (DS), particle size of the filler, compression force, and content of drug substance. All factors were varied at two levels plus a center point, except the drug substance content, which was varied at five levels. Six tablets from each experimental point were measured with transmission NIR and Raman spectroscopy, and their concentration of DS was determined for a third of those tablets. Principal component analysis of NIR and Raman spectra showed that the drug substance content and particle size, the particle size of the filler, and the compression force affected both NIR and Raman spectra. For quantitative assessment, orthogonal partial least squares regression was applied. All factors varied in the experimental design influenced the prediction of the DS content to some extent, both for NIR and Raman spectroscopy, the particle size of the filler having the largest effect. When all matrix variations were included in the multivariate calibrations, however, good predictions of all types of tablets were obtained, both for NIR and Raman spectroscopy. The prediction error using transmission Raman spectroscopy was about 30% lower than that obtained with transmission NIR spectroscopy.

Prediction of soil organic carbon in a coal mining area by Vis-NIR spectroscopy.

PubMed

Sun, Wenjuan; Li, Xinju; Niu, Beibei

2018-01-01

Coal mining has led to increasingly serious land subsidence, and the reclamation of the subsided land has become a hot topic of concern for governments and scholars. Soil quality of reclaimed land is the key indicator to the evaluation of the reclamation effect; hence, rapid monitoring and evaluation of reclaimed land is of great significance. Visible-near infrared (Vis-NIR) spectroscopy has been shown to be a rapid, timely and efficient tool for the prediction of soil organic carbon (SOC). In this study, 104 soil samples were collected from the Baodian mining area of Shandong province. Vis-NIR reflectance spectra and soil organic carbon content were then measured under laboratory conditions. The spectral data were first denoised using the Savitzky-Golay (SG) convolution smoothing method or the multiple scattering correction (MSC) method, after which the spectral reflectance (R) was subjected to reciprocal, reciprocal logarithm and differential transformations to improve spectral sensitivity. Finally, regression models for estimating the SOC content by the spectral data were constructed using partial least squares regression (PLSR). The results showed that: (1) The SOC content in the mining area was generally low (at the below-average level) and exhibited great variability. (2) The spectral reflectance increased with the decrease of soil organic carbon content. In addition, the sensitivity of the spectrum to the change in SOC content, especially that in the near-infrared band of the original reflectance, decreased when the SOC content was low. (3) The modeling results performed best when the spectral reflectance was preprocessed by Savitzky-Golay (SG) smoothing coupled with multiple scattering correction (MSC) and first-order differential transformation (modeling R2 = 0.86, RMSE = 2.00 g/kg, verification R2 = 0.78, RMSE = 1.81 g/kg, and RPD = 2.69). In addition, the first-order differential of R combined with SG, MSC with R, SG together with MSC and R also produced better modeling results than other pretreatment combinations. Vis-NIR modeling with specific spectral preprocessing methods could predict SOC content effectively.

Starch waxiness in hexaploid wheat (Triticum aestivum L.) by NIR reflectance spectroscopy

USDA-ARS?s Scientific Manuscript database

Starch, the primary energy storage component of plants, consists of two large macromolecules, amylose and amylopectin. Each molecule is composed of long chains of alpha-D-glucopyranosyl units, with branching present in amylopectin and absent in amylose. The relative abundance of these two molecules ...

Estimation of soil profile physical and chemical properties using a VIS-NIR-EC-force probe

USDA-ARS?s Scientific Manuscript database

Combining data collected in-field from multiple soil sensors has the potential to improve the efficiency and accuracy of soil property estimates. Optical diffuse reflectance spectroscopy (DRS) has been used to estimate many important soil properties, such as soil carbon, water content, and texture. ...

Identification of informative bands in the short-wavelength NIR region for non-invasive blood glucose measurement.

PubMed

Uwadaira, Yasuhiro; Ikehata, Akifumi; Momose, Akiko; Miura, Masayo

2016-07-01

The "glucose-linked wavelength" in the short-wavelength near-infrared (NIR) region, in which the light intensity reflected from the hand palm exhibits a good correlation to the blood glucose value, was investigated. We performed 391 2-h carbohydrate tolerance tests (CTTs) using 34 participants and a glucose-linked wavelength was successfully observed in almost every CTT; however, this wavelength varied between CTTs even for the same person. The large resulting data set revealed the distribution of the informative wavelength. The blood glucose values were efficiently estimated by a simple linear regression with clinically acceptable accuracies. The result suggested the potential for constructing a personalized low-invasive blood glucose sensor using short-wavelength NIR spectroscopy.

Use of visible and near infrared reflectance spectra to predict lipid peroxidation of light lamb meat and discriminate dam's feeding systems.

PubMed

Ripoll, G; Lobón, S; Joy, M

2018-09-01

Measurement of thiobarbituric acid reactive substances (TBARS) is a well-established method for determine lipid oxidation in meat. This assay, however, is time-consuming and generates undesired chemical waste. Dam's milk is the principal source of vitamins and provitamins that delay lipid oxidation of light lamb meat; these compounds are stored in the lamb's muscle tissue. Hence, lamb meat could be used to determine the origin of the dam's diet. The aim of this study is to evaluate Near-infrared reflectance spectroscopy (NIRS) as a tool for determining the lipid peroxidation of light lamb meat and differentiate the meat of light lambs according the diet of their dams during lactation (grazing alfalfa, lucerne, or fed a total mixed ration). NIRS using select wavelengths was able to detect the lipid oxidation of meat (TBARS method). NIRS can detect analytes at concentrations of parts per million. Moreover, the feed diets were discriminated successfully. Copyright © 2018 Elsevier Ltd. All rights reserved.

Classification and quantification analysis of peach kernel from different origins with near-infrared diffuse reflection spectroscopy

PubMed Central

Liu, Wei; Wang, Zhen-Zhong; Qing, Jian-Ping; Li, Hong-Juan; Xiao, Wei

2014-01-01

Background: Peach kernels which contain kinds of fatty acids play an important role in the regulation of a variety of physiological and biological functions. Objective: To establish an innovative and rapid diffuse reflectance near-infrared spectroscopy (DR-NIR) analysis method along with chemometric techniques for the qualitative and quantitative determination of a peach kernel. Materials and Methods: Peach kernel samples from nine different origins were analyzed with high-performance liquid chromatography (HPLC) as a reference method. DR-NIR is in the spectral range 1100-2300 nm. Principal component analysis (PCA) and partial least squares regression (PLSR) algorithm were applied to obtain prediction models, The Savitzky-Golay derivative and first derivative were adopted for the spectral pre-processing, PCA was applied to classify the varieties of those samples. For the quantitative calibration, the models of linoleic and oleinic acids were established with the PLSR algorithm and the optimal principal component (PC) numbers were selected with leave-one-out (LOO) cross-validation. The established models were evaluated with the root mean square error of deviation (RMSED) and corresponding correlation coefficients (R2). Results: The PCA results of DR-NIR spectra yield clear classification of the two varieties of peach kernel. PLSR had a better predictive ability. The correlation coefficients of the two calibration models were above 0.99, and the RMSED of linoleic and oleinic acids were 1.266% and 1.412%, respectively. Conclusion: The DR-NIR combined with PCA and PLSR algorithm could be used efficiently to identify and quantify peach kernels and also help to solve variety problem. PMID:25422544

NIRS in Space?

NASA Technical Reports Server (NTRS)

Peterson, David L.; Condon, Estelle (Technical Monitor)

2000-01-01

Proponents of near infrared reflectance spectroscopy (NIRS) have been exceptionally successful in applying NIRS techniques to many instances of organic material analyses. While this research and development began in the 1950s, in recent years, stimulation of advancements in instrumentation is allowing NIRS to begin to find its way into the food processing systems, into food quality and safety, textiles and much more. And, imaging high spectral resolution spectrometers are now being evaluated for the rapid scanning of foodstuffs, such as the inspection of whole chicken carcasses for fecal contamination. The imaging methods are also finding their way into medical applications, such as the non-intrusive monitoring of blood oxygenation in newborns. Can these scientific insights also be taken into space and successfully used to measure the Earth's condition? Is there an analog between the organic analyses in the laboratory and clinical settings and the study of Earth's living biosphere? How are the methods comparable and how do they differ?

Comparison of Attenuated Total Reflectance Mid-Infrared, Near Infrared, and 1H-Nuclear Magnetic Resonance Spectroscopies for the Determination of Coffee's Geographical Origin.

PubMed

Medina, Jessica; Caro Rodríguez, Diana; Arana, Victoria A; Bernal, Andrés; Esseiva, Pierre; Wist, Julien

2017-01-01

The sensorial properties of Colombian coffee are renowned worldwide, which is reflected in its market value. This raises the threat of fraud by adulteration using coffee grains from other countries, thus creating a demand for robust and cost-effective methods for the determination of geographical origin of coffee samples. Spectroscopic techniques such as Nuclear Magnetic Resonance (NMR), near infrared (NIR), and mid-infrared (mIR) have arisen as strong candidates for the task. Although a body of work exists that reports on their individual performances, a faithful comparison has not been established yet. We evaluated the performance of 1 H-NMR, Attenuated Total Reflectance mIR (ATR-mIR), and NIR applied to fraud detection in Colombian coffee. For each technique, we built classification models for discrimination by species ( C. arabica versus C. canephora (or robusta )) and by origin (Colombia versus other C. arabica ) using a common set of coffee samples. All techniques successfully discriminated samples by species, as expected. Regarding origin determination, ATR-mIR and 1 H-NMR showed comparable capacity to discriminate Colombian coffee samples, while NIR fell short by comparison. In conclusion, ATR-mIR, a less common technique in the field of coffee adulteration and fraud detection, emerges as a strong candidate, faster and with lower cost compared to 1 H-NMR and more discriminating compared to NIR.

Modelling postharvest quality of blueberry affected by biological variability using image and spectral data.

PubMed

Hu, Meng-Han; Dong, Qing-Li; Liu, Bao-Lin

2016-08-01

Hyperspectral reflectance and transmittance sensing as well as near-infrared (NIR) spectroscopy were investigated as non-destructive tools for estimating blueberry firmness, elastic modulus and soluble solid content (SSC). Least squares-support vector machine models were established from these three spectra based on samples from three cultivars viz. Bluecrop, Duke and M2 and two harvest years viz. 2014 and 2015 for predicting blueberry postharvest quality. One-cultivar reflectance models (establishing model using one cultivar) derived better results than the corresponding transmittance and NIR models for predicting blueberry firmness with few cultivar effects. Two-cultivar NIR models (establishing model using two cultivars) proved to be suitable for estimating blueberry SSC with correlations over 0.83. Rp (RMSEp ) values of the three-cultivar reflectance models (establishing model using 75% of three cultivars) were 0.73 (0.094) and 0.73 (0.186), respectively , for predicting blueberry firmness and elastic modulus. For SSC prediction, the three-cultivar NIR model was found to achieve an Rp (RMSEp ) value of 0.85 (0.090). Adding Bluecrop samples harvested in 2014 could enhance the three-cultivar model robustness for firmness and elastic modulus. The above results indicated the potential for using spatial and spectral techniques to develop robust models for predicting blueberry postharvest quality containing biological variability. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Comparing near-infrared conventional diffuse reflectance spectroscopy and hyperspectral imaging for determination of the bulk properties of solid samples by multivariate regression: determination of Mooney viscosity and plasticity indices of natural rubber.

PubMed

Juliano da Silva, Carlos; Pasquini, Celio

2015-01-21

Conventional reflectance spectroscopy (NIRS) and hyperspectral imaging (HI) in the near-infrared region (1000-2500 nm) are evaluated and compared, using, as the case study, the determination of relevant properties related to the quality of natural rubber. Mooney viscosity (MV) and plasticity indices (PI) (PI0 - original plasticity, PI30 - plasticity after accelerated aging, and PRI - the plasticity retention index after accelerated aging) of rubber were determined using multivariate regression models. Two hundred and eighty six samples of rubber were measured using conventional and hyperspectral near-infrared imaging reflectance instruments in the range of 1000-2500 nm. The sample set was split into regression (n = 191) and external validation (n = 95) sub-sets. Three instruments were employed for data acquisition: a line scanning hyperspectral camera and two conventional FT-NIR spectrometers. Sample heterogeneity was evaluated using hyperspectral images obtained with a resolution of 150 × 150 μm and principal component analysis. The probed sample area (5 cm(2); 24,000 pixels) to achieve representativeness was found to be equivalent to the average of 6 spectra for a 1 cm diameter probing circular window of one FT-NIR instrument. The other spectrophotometer can probe the whole sample in only one measurement. The results show that the rubber properties can be determined with very similar accuracy and precision by Partial Least Square (PLS) regression models regardless of whether HI-NIR or conventional FT-NIR produce the spectral datasets. The best Root Mean Square Errors of Prediction (RMSEPs) of external validation for MV, PI0, PI30, and PRI were 4.3, 1.8, 3.4, and 5.3%, respectively. Though the quantitative results provided by the three instruments can be considered equivalent, the hyperspectral imaging instrument presents a number of advantages, being about 6 times faster than conventional bulk spectrometers, producing robust spectral data by ensuring sample representativeness, and minimizing the effect of the presence of contaminants.

Crop/weed discrimination using near-infrared reflectance spectroscopy (NIRS)

NASA Astrophysics Data System (ADS)

Zhang, Yun; He, Yong

2006-09-01

The traditional uniform herbicide application often results in an over chemical residues on soil, crop plants and agriculture produce, which have imperiled the environment and food security. Near-infrared reflectance spectroscopy (NIRS) offers a promising means for weed detection and site-specific herbicide application. In laboratory, a total of 90 samples (30 for each species) of the detached leaves of two weeds, i.e., threeseeded mercury (Acalypha australis L.) and fourleafed duckweed (Marsilea quadrfolia L.), and one crop soybean (Glycine max) was investigated for NIRS on 325- 1075 nm using a field spectroradiometer. 20 absorbance samples of each species after pretreatment were exported and the lacked Y variables were assigned independent values for partial least squares (PLS) analysis. During the combined principle component analysis (PCA) on 400-1000 nm, the PC1 and PC2 could together explain over 91% of the total variance and detect the three plant species with 98.3% accuracy. The full-cross validation results of PLS, i.e., standard error of prediction (SEP) 0.247, correlation coefficient (r) 0.954 and root mean square error of prediction (RMSEP) 0.245, indicated an optimum model for weed identification. By predicting the remaining 10 samples of each species in the PLS model, the results with deviation presented a 100% crop/weed detection rate. Thus, it could be concluded that PLS was an available alternative of for qualitative weed discrimination on NTRS.

Comparison of NIR chemical imaging with conventional NIR, Raman and ATR-IR spectroscopy for quantification of furosemide crystal polymorphs in ternary powder mixtures.

PubMed

Schönbichler, S A; Bittner, L K H; Weiss, A K H; Griesser, U J; Pallua, J D; Huck, C W

2013-08-01

The aim of this study was to evaluate the ability of near-infrared chemical imaging (NIR-CI), near-infrared (NIR), Raman and attenuated-total-reflectance infrared (ATR-IR) spectroscopy to quantify three polymorphic forms (I, II, III) of furosemide in ternary powder mixtures. For this purpose, partial least-squares (PLS) regression models were developed, and different data preprocessing algorithms such as normalization, standard normal variate (SNV), multiplicative scatter correction (MSC) and 1st to 3rd derivatives were applied to reduce the influence of systematic disturbances. The performance of the methods was evaluated by comparison of the standard error of cross-validation (SECV), R(2), and the ratio performance deviation (RPD). Limits of detection (LOD) and limits of quantification (LOQ) of all methods were determined. For NIR-CI, a SECVcorr-spec and a SECVsingle-pixel corrected were calculated to assess the loss of accuracy by taking advantage of the spatial information. NIR-CI showed a SECVcorr-spec (SECVsingle-pixel corrected) of 2.82% (3.71%), 3.49% (4.65%), and 4.10% (5.06%) for form I, II, III. NIR had a SECV of 2.98%, 3.62%, and 2.75%, and Raman reached 3.25%, 3.08%, and 3.18%. The SECV of the ATR-IR models were 7.46%, 7.18%, and 12.08%. This study proves that NIR-CI, NIR, and Raman are well suited to quantify forms I-III of furosemide in ternary mixtures. Because of the pressure-dependent conversion of form II to form I, ATR-IR was found to be less appropriate for an accurate quantification of the mixtures. In this study, the capability of NIR-CI for the quantification of polymorphic ternary mixtures was compared with conventional spectroscopic techniques for the first time. For this purpose, a new way of spectra selection was chosen, and two kinds of SECVs were calculated to achieve a better comparability of NIR-CI to NIR, Raman, and ATR-IR. Copyright © 2013 Elsevier B.V. All rights reserved.

Hyperspectral reflectance imaging technique for visualization of moisture distribution in cooked chicken breast

USDA-ARS?s Scientific Manuscript database

Spectroscopy has proven to be an efficient tool for measuring the properties of meat. In this article, the hyperspectral imaging (HSI) technique is investigated for the determination of moisture content in cooked chicken breast over the VIS/NIR (400–1000 nm) spectral ranges. Moisture measurements we...

Slow spontaneous hemodynamic oscillations during sleep measured with near-infrared spectroscopy

NASA Astrophysics Data System (ADS)

Virtanen, Jaakko; Näsi, Tiina; Noponen, Tommi; Toppila, Jussi; Salmi, Tapani; Ilmoniemi, Risto J.

2011-07-01

Spontaneous cerebral hemodynamic oscillations below 100 mHz reflect the level of cerebral activity, modulate hemodynamic responses to tasks and stimuli, and may aid in detecting various pathologies of the brain. Near-infrared spectroscopy (NIRS) is ideally suited for both measuring spontaneous hemodynamic oscillations and monitoring sleep, but little research has been performed to combine these two applications. We analyzed 30 all-night NIRS-electroencephalography (EEG) sleep recordings to investigate spontaneous hemodynamic activity relative to sleep stages determined by polysomnography. Signal power of hemodynamic oscillations in the low-frequency (LF, 40-150 mHz) and very-low-frequency (VLF, 3-40 mHz) bands decreased in slow-wave sleep (SWS) compared to light sleep (LS) and rapid-eye-movement (REM) sleep. No statistically significant (p < 0.05) differences in oscillation power between LS and REM were observed. However, the period of VLF oscillations around 8 mHz increased in REM sleep in line with earlier studies with other modalities. These results increase our knowledge of the physiology of sleep, complement EEG data, and demonstrate the applicability of NIRS to studying spontaneous hemodynamic fluctuations during sleep.

Mapping polycyclic aromatic hydrocarbon and total toxicity equivalent soil concentrations by visible and near-infrared spectroscopy.

PubMed

Okparanma, Reuben N; Coulon, Frederic; Mayr, Thomas; Mouazen, Abdul M

2014-09-01

In this study, we used data from spectroscopic models based on visible and near-infrared (vis-NIR; 350-2500 nm) diffuse reflectance spectroscopy to develop soil maps of polycyclic aromatic hydrocarbons (PAHs) and total toxicity equivalent concentrations (TTEC) of the PAH mixture. The TTEC maps were then used for hazard assessment of three petroleum release sites in the Niger Delta province of Nigeria (5.317°N, 6.467°E). As the paired t-test revealed, there were non-significant (p > 0.05) differences between soil maps of PAH and TTEC developed with chemically measured and vis-NIR-predicted data. Comparison maps of PAH showed a slight to moderate agreement between measured and predicted data (Kappa coefficient = 0.19-0.56). Using proposed generic assessment criteria, hazard assessment showed that the degree of action for site-specific risk assessment and/or remediation is similar for both measurement methods. This demonstrates that the vis-NIR method may be useful for monitoring hydrocarbon contamination in a petroleum release site. Copyright © 2014 Elsevier Ltd. All rights reserved.

Use of near infrared spectroscopy for estimating meat chemical composition, quality traits and fatty acid content from cattle fed sunflower or flaxseed.

PubMed

Prieto, N; López-Campos, O; Aalhus, J L; Dugan, M E R; Juárez, M; Uttaro, B

2014-10-01

This study tested the ability of near infrared reflectance spectroscopy (NIRS) to predict meat chemical composition, quality traits and fatty acid (FA) composition from 63 steers fed sunflower or flaxseed in combination with high forage diets. NIRS calibrations, tested by cross-validation, were successful for predicting crude protein, moisture and fat content with coefficients of determination (R(2)) (RMSECV, g·100g(-1) wet matter) of 0.85 (0.48), 0.90 (0.60) and 0.86 (1.08), respectively, but were not reliable for meat quality attributes. This technology accurately predicted saturated, monounsaturated and branched FA and conjugated linoleic acid content (R(2): 0.83-0.97; RMSECV: 0.04-1.15mg·g(-1) tissue) and might be suitable for screening purposes in meat based on the content of FAs beneficial to human health such as rumenic and vaccenic acids. Further research applying NIRS to estimate meat quality attributes will require the use on-line of a fibre-optic probe on intact samples. Copyright © 2014 Elsevier Ltd. All rights reserved.

A Review on the Role of Vibrational Spectroscopy as An Analytical Method to Measure Starch Biochemical and Biophysical Properties in Cereals and Starchy Foods

PubMed Central

Cozzolino, D.; Degner, S.; Eglinton, J.

2014-01-01

Starch is the major component of cereal grains and starchy foods, and changes in its biophysical and biochemical properties (e.g., amylose, amylopectin, pasting, gelatinization, viscosity) will have a direct effect on its end use properties (e.g., bread, malt, polymers). The use of rapid and non-destructive methods to study and monitor starch properties, such as gelatinization, retrogradation, water absorption in cereals and starchy foods, is of great interest in order to improve and assess their quality. In recent years, near infrared reflectance (NIR) and mid infrared (MIR) spectroscopy have been explored to predict several quality parameters, such as those generated by instrumental methods commonly used in routine analysis like the rapid visco analyser (RVA) or viscometers. In this review, applications of both NIR and MIR spectroscopy to measure and monitor starch biochemical (amylose, amylopectin, starch) and biophysical properties (e.g., pasting properties) will be presented and discussed. PMID:28234340

Fourier transform near-infrared spectroscopy application for sea salt quality evaluation.

PubMed

Galvis-Sánchez, Andrea C; Lopes, João Almeida; Delgadillo, Ivonne; Rangel, António O S S

2011-10-26

Near-infrared (NIR) spectroscopy in diffuse reflectance mode was explored with the objective of discriminating sea salts according to their quality type (traditional salt vs "flower of salt") and geographical origin (Atlantic vs Mediterranean). Sea salts were also analyzed in terms of Ca(2+), Mg(2+), K(+), alkalinity, and sulfate concentrations to support spectroscopic results. High concentrations of Mg(2+) and K(+) characterized Atlantic samples, while a high Ca(2+) content was observed in traditional sea salts. A partial least-squares discriminant analysis model considering the 8500-7500 cm(-1) region permitted the discrimination of salts by quality types. The regions 4650-4350 and 5900-5500 cm(-1) allowed salts classification according to their geographical origin. It was possible to classify correctly 85.3 and 94.8% of the analyzed samples according to the salt type and to the geographical origin, respectively. These results demonstrated that NIR spectroscopy is a suitable and very efficient tool for sea salt quality evaluation.

7 CFR 801.7 - Reference methods and tolerances for near-infrared spectroscopy (NIRS) analyzers.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 7 2010-01-01 2010-01-01 false Reference methods and tolerances for near-infrared spectroscopy (NIRS) analyzers. 801.7 Section 801.7 Agriculture Regulations of the Department of Agriculture... methods and tolerances for near-infrared spectroscopy (NIRS) analyzers. (a) Reference methods. (1) The...

Recent advances in the use of NIR spectroscopy for qualitative control and protection of extra virgin olive oil

USDA-ARS?s Scientific Manuscript database

Recent studies on the use of near infrared (NIR) spectroscopy for the qualitative characterization of extra virgin olive oil, are reported and discussed in this paper. Research results confirms that NIR spectroscopy, combined with chemometric data analysis, allows to simultaneously evaluate all qual...

Total anthocyanin content determination in intact açaí (Euterpe oleracea Mart.) and palmitero-juçara (Euterpe edulis Mart.) fruit using near infrared spectroscopy (NIR) and multivariate calibration.

PubMed

Inácio, Maria Raquel Cavalcanti; de Lima, Kássio Michell Gomes; Lopes, Valquiria Garcia; Pessoa, José Dalton Cruz; de Almeida Teixeira, Gustavo Henrique

2013-02-15

The aim of this study was to evaluate near-infrared reflectance spectroscopy (NIR), and multivariate calibration potential as a rapid method to determinate anthocyanin content in intact fruit (açaí and palmitero-juçara). Several multivariate calibration techniques, including partial least squares (PLS), interval partial least squares, genetic algorithm, successive projections algorithm, and net analyte signal were compared and validated by establishing figures of merit. Suitable results were obtained with the PLS model (four latent variables and 5-point smoothing) with a detection limit of 6.2 g kg(-1), limit of quantification of 20.7 g kg(-1), accuracy estimated as root mean square error of prediction of 4.8 g kg(-1), mean selectivity of 0.79 g kg(-1), sensitivity of 5.04×10(-3) g kg(-1), precision of 27.8 g kg(-1), and signal-to-noise ratio of 1.04×10(-3) g kg(-1). These results suggest NIR spectroscopy and multivariate calibration can be effectively used to determine anthocyanin content in intact açaí and palmitero-juçara fruit. Copyright © 2012 Elsevier Ltd. All rights reserved.

Rapid non-destructive assessment of pork edible quality by using VIS/NIR spectroscopic technique

NASA Astrophysics Data System (ADS)

Zhang, Leilei; Peng, Yankun; Dhakal, Sagar; Song, Yulin; Zhao, Juan; Zhao, Songwei

2013-05-01

The objectives of this research were to develop a rapid non-destructive method to evaluate the edible quality of chilled pork. A total of 42 samples were packed in seal plastic bags and stored at 4°C for 1 to 21 days. Reflectance spectra were collected from visible/near-infrared spectroscopy system in the range of 400nm to 1100nm. Microbiological, physicochemical and organoleptic characteristics such as the total viable counts (TVC), total volatile basic-nitrogen (TVB-N), pH value and color parameters L* were determined to appraise pork edible quality. Savitzky-Golay (SG) based on five and eleven smoothing points, Multiple Scattering Correlation (MSC) and first derivative pre-processing methods were employed to eliminate the spectra noise. The support vector machines (SVM) and partial least square regression (PLSR) were applied to establish prediction models using the de-noised spectra. A linear correlation was developed between the VIS/NIR spectroscopy and parameters such as TVC, TVB-N, pH and color parameter L* indexes, which could gain prediction results with Rv of 0.931, 0.844, 0.805 and 0.852, respectively. The results demonstrated that VIS/NIR spectroscopy technique combined with SVM possesses a powerful assessment capability. It can provide a potential tool for detecting pork edible quality rapidly and non-destructively.

Early optical detection of cerebral edema in vivo.

PubMed

Gill, Amandip S; Rajneesh, Kiran F; Owen, Christopher M; Yeh, James; Hsu, Mike; Binder, Devin K

2011-02-01

Cerebral edema is a significant cause of morbidity and mortality in diverse disease states. Currently, the means to detect progressive cerebral edema in vivo includes the use of intracranial pressure (ICP) monitors and/or serial radiological studies. However, ICP measurements exhibit a high degree of variability, and ICP monitors detect edema only after it becomes sufficient to significantly raise ICP. The authors report the development of 2 distinct minimally invasive fiberoptic near-infrared (NIR) techniques able to directly detect early cerebral edema. Cytotoxic brain edema was induced in adult CD1 mice via water intoxication by intraperitoneal water administration (30% body weight intraperitoneally). An implantable dual-fiberoptic probe was stereotactically placed into the cerebral cortex and connected to optical source and detector hardware. Optical sources consisted of either broadband halogen illumination or a single-wavelength NIR laser diode, and the detector was a sensitive NIR spectrometer or optical power meter. In one subset of animals, a left-sided craniectomy was performed to obtain cortical biopsies for water-content determination to verify cerebral edema. In another subset of animals, an ICP transducer was placed on the contralateral cortex, which was synchronized to a computer and time stamped. Using either broadband illumination with NIR spectroscopy or single-wavelength laser diode illumination with optical power meter detection, the authors detected a reduction in NIR optical reflectance during early cerebral edema. The time intervals between water injection (Time Point 0), optical trigger (defined as a 2-SD change in optical reflectance from baseline), and defined threshold ICP values of 10, 15 and 20 mm Hg were calculated. Reduction in NIR reflectance occurred significantly earlier than any of the ICP thresholds (p < 0.001). Saline-injected control mice exhibited a steady baseline optical signal. There was a significant correlation between reflectance change and tissue specific gravity of the cortical biopsies, further validating the dual-fiberoptic probe as a direct measure of cerebral edema. Compared with traditional ICP monitoring, the aforementioned minimally invasive NIR techniques allow for the significantly earlier detection of cerebral edema, which may be of clinical utility in the identification and thus early treatment of cerebral edema.

Development and Validation of a Near-Infrared Spectroscopy Method for the Prediction of Acrylamide Content in French-Fried Potato.

PubMed

Adedipe, Oluwatosin E; Johanningsmeier, Suzanne D; Truong, Van-Den; Yencho, G Craig

2016-03-02

This study investigated the ability of near-infrared spectroscopy (NIRS) to predict acrylamide content in French-fried potato. Potato flour spiked with acrylamide (50-8000 μg/kg) was used to determine if acrylamide could be accurately predicted in a potato matrix. French fries produced with various pretreatments and cook times (n = 84) and obtained from quick-service restaurants (n = 64) were used for model development and validation. Acrylamide was quantified using gas chromatography-mass spectrometry, and reflectance spectra (400-2500 nm) of each freeze-dried sample were captured on a Foss XDS Rapid Content Analyzer-NIR spectrometer. Partial least-squares (PLS) discriminant analysis and PLS regression modeling demonstrated that NIRS could accurately detect acrylamide content as low as 50 μg/kg in the model potato matrix. Prediction errors of 135 μg/kg (R(2) = 0.98) and 255 μg/kg (R(2) = 0.93) were achieved with the best PLS models for acrylamide prediction in Russet Norkotah French-fried potato and multiple samples of unknown varieties, respectively. The findings indicate that NIRS can be used as a screening tool in potato breeding and potato processing research to reduce acrylamide in the food supply.

Characterizing and authenticating Montilla-Moriles PDO vinegars using near infrared reflectance spectroscopy (NIRS) technology.

PubMed

De la Haba, María-José; Arias, Mar; Ramírez, Pilar; López, María-Isabel; Sánchez, María-Teresa

2014-02-20

This study assessed the potential of near infrared (NIR) spectroscopy as a non-destructive method for characterizing Protected Designation of Origin (PDO) "Vinagres de Montilla-Moriles" wine vinegars and for classifying them as a function of the manufacturing process used. Three spectrophotometers were evaluated for this purpose: two monochromator instruments (Foss NIRSystems 6500 SY-I and Foss NIRSystems 6500 SY-II; spectral range 400-2,500 nm in both cases) and a diode-array instrument (Corona 45 VIS/NIR; spectral range 380-1,700 nm). A total of 70 samples were used to predict major chemical quality parameters (total acidity, fixed acidity, volatile acidity, pH, dry extract, ash, acetoin, methanol, total polyphenols, color (tonality and intensity), and alcohol content), and to construct models for the classification of vinegars as a function of the manufacturing method used. The results obtained indicate that this non-invasive technology can be used successfully by the vinegar industry and by PDO regulators for the routine analysis of vinegars in order to authenticate them and to detect potential fraud. Slightly better results were achieved with the two monochromator instruments. The findings also highlight the potential of these NIR instruments for predicting the manufacturing process used, this being of particular value for the industrial authentication of traditional wine vinegars.

Critical Review of Noninvasive Optical Technologies for Wound Imaging

PubMed Central

Jayachandran, Maanasa; Rodriguez, Suset; Solis, Elizabeth; Lei, Jiali; Godavarty, Anuradha

2016-01-01

Significance: Noninvasive imaging approaches can provide greater information about a wound than visual inspection during the wound healing and treatment process. This review article focuses on various optical imaging techniques developed to image different wound types (more specifically ulcers). Recent Advances: The noninvasive optical imaging approaches in this review include hyperspectral imaging, multispectral imaging, near-infrared spectroscopy (NIRS), diffuse reflectance spectroscopy, optical coherence tomography, laser Doppler imaging, laser speckle imaging, spatial frequency domain imaging, and fluorescence imaging. The various wounds imaged using these techniques include open wounds, chronic wounds, diabetic foot ulcers, decubitus ulcers, venous leg ulcers, and burns. Preliminary work in the development and implementation of a near-infrared optical scanner for wound imaging as a noncontact hand-held device is briefly described. The technology is based on NIRS and has demonstrated its potential to differentiate a healing from nonhealing wound region. Critical Issues: While most of the optical imaging techniques can penetrate few hundred microns to a 1–2 mm from the wound surface, NIRS has the potential to penetrate deeper, demonstrating the potential to image internal wounds. Future Directions: All the technologies are currently at various stages of translational efforts to the clinic, with NIRS holding a greater promise for physiological assessment of the wounds internal, beyond the gold-standard visual assessment. PMID:27602254

Detection of aflatoxin and surface mould contaminated figs by using Fourier transform near-infrared reflectance spectroscopy.

PubMed

Durmuş, Efkan; Güneş, Ali; Kalkan, Habil

2017-01-01

Aflatoxins are toxic metabolites that are mainly produced by members of the Aspergillus section Flavi on many agricultural products. Certain agricultural products such as figs are known to be high risk products for aflatoxin contamination. Aflatoxin contaminated figs may show a bright greenish yellow fluorescence (BGYF) under ultraviolet (UV) light at a wavelength of 365 nm. Traditionally, BGYF positive figs are manually selected by workers. However, manual selection depends on the expertise level of the workers and it may cause them skin-related health problems due to UV radiation. In this study, we propose a non-invasive approach to detect aflatoxin and surface mould contaminated figs by using Fourier transform near-infrared (FT-NIR) reflectance spectroscopy. A classification accuracy of 100% is achieved for classifying the figs into aflatoxin contaminated/uncontaminated and surface mould contaminated/uncontaminated categories. In addition, a strong correlation has been found between aflatoxin and surface mould. Combined with pattern classification methods, the NIR spectroscopy can be used to detect aflatoxin contaminated figs non-invasively. Furthermore, a positive correlation between surface mould and aflatoxin contamination leads to a promising alternative indicator for the detection of aflatoxin-contaminated figs. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Near infrared spectroscopy for determination of various physical, chemical and biochemical properties in Mediterranean soils.

PubMed

Zornoza, R; Guerrero, C; Mataix-Solera, J; Scow, K M; Arcenegui, V; Mataix-Beneyto, J

2008-07-01

The potential of near infrared (NIR) reflectance spectroscopy to predict various physical, chemical and biochemical properties in Mediterranean soils from SE Spain was evaluated. Soil samples (n=393) were obtained by sampling thirteen locations during three years (2003-2005 period). These samples had a wide range of soil characteristics due to variations in land use, vegetation cover and specific climatic conditions. Biochemical properties also included microbial biomarkers based on phospholipid fatty acids (PLFA). Partial least squares (PLS) regression with cross validation was used to establish relationships between the NIR spectra and the reference data from physical, chemical and biochemical analyses. Based on the values of coefficient of determination (r(2)) and the ratio of standard deviation of validation set to root mean square error of cross validation (RPD), predicted results were evaluated as excellent (r(2)>0.90 and RPD>3) for soil organic carbon, Kjeldahl nitrogen, soil moisture, cation exchange capacity, microbial biomass carbon, basal soil respiration, acid phosphatase activity, β-glucosidase activity and PLFA biomarkers for total bacteria, Gram positive bacteria, actinomycetes, vesicular-arbuscular mycorrhizal fungi and total PLFA biomass. Good predictions (0.81

Influence of multiple scattering and absorption on the full scattering profile and the isobaric point in tissue

NASA Astrophysics Data System (ADS)

Duadi, Hamootal; Fixler, Dror

2015-05-01

Light reflectance and transmission from soft tissue has been utilized in noninvasive clinical measurement devices such as the photoplethysmograph (PPG) and reflectance pulse oximeter. Incident light on the skin travels into the underlying layers and is in part reflected back to the surface, in part transferred and in part absorbed. Most methods of near infrared (NIR) spectroscopy focus on the volume reflectance from a semi-infinite sample, while very few measure transmission. We have previously shown that examining the full scattering profile (angular distribution of exiting photons) provides more comprehensive information when measuring from a cylindrical tissue. Furthermore, an isobaric point was found which is not dependent on changes in the reduced scattering coefficient. The angle corresponding to this isobaric point depends on the tissue diameter. We investigated the role of multiple scattering and absorption on the full scattering profile of a cylindrical tissue. First, we define the range in which multiple scattering occurs for different tissue diameters. Next, we examine the role of the absorption coefficient in the attenuation of the full scattering profile. We demonstrate that the absorption linearly influences the intensity at each angle of the full scattering profile and, more importantly, the absorption does not change the position of the isobaric point. The findings of this work demonstrate a realistic model for optical tissue measurements such as NIR spectroscopy, PPG, and pulse oximetery.

The potential of near infrared reflectance spectroscopy (NIRS) for the estimation of agroindustrial compost quality.

PubMed

Galvez-Sola, L; Moral, R; Perez-Murcia, M D; Perez-Espinosa, A; Bustamante, M A; Martinez-Sabater, E; Paredes, C

2010-02-15

Composting is an environmentally friendly alternative for the recycling of organic wastes and its use is increasing in recent years. An exhaustive monitoring of the composting process and of the final compost characteristics is necessary to certify that the values of compost characteristics are within the limits established by the legislation in order to obtain a safe and marketable product. The analysis of these parameters on each composting batch in the commercial composting plant is time-consuming and expensive. So, their estimation in the composting facilities based on the use of near infrared reflectance spectroscopy (NIRS) could be an interesting approach in order to monitor compost quality. In this study, more than 300 samples from 20 different composting procedures were used to calibrate and validate the NIRS estimation of compost properties (pH, electrical conductivity (EC), total organic matter (TOM), total organic carbon (TOC), total nitrogen (TN) and C/N ratio, macronutrient contents (N, P, K) and potentially pollutant element concentrations (Fe, Cu, Mn and Zn)). The composts used were elaborated using different organic wastes from agroindustrial activities (GS: grape stalk; EGM: exhausted grape marc; GM: grape marc; V: vinasse; CJW: citrus juice waste; Alpeorujo: olive-oil waste; AS: almond skin; EP: exhausted peat; TSW: tomato soup waste; SMS: spent mushroom substrate) co-composted with manures (CM: cattle manure; PM: poultry manure) or urban wastes (SS: sewage sludge) The estimation results showed that the NIRS technique needs to be fitted to each element and property, using specific spectrum transformations, in order to achieve an acceptable accuracy in the prediction. However, excellent prediction results were obtained for TOM and TOC, successful calibrations for pH, EC, Fe and Mn, and moderately successful estimations for TN, C/N ratio, P, K, Cu and Zn.

Identification of anisodamine tablets by Raman and near-infrared spectroscopy with chemometrics.

PubMed

Li, Lian; Zang, Hengchang; Li, Jun; Chen, Dejun; Li, Tao; Wang, Fengshan

2014-06-05

Vibrational spectroscopy including Raman and near-infrared (NIR) spectroscopy has become an attractive tool for pharmaceutical analysis. In this study, effective calibration models for the identification of anisodamine tablet and its counterfeit and the distinguishment of manufacturing plants, based on Raman and NIR spectroscopy, were built, respectively. Anisodamine counterfeit tablets were identified by Raman spectroscopy with correlation coefficient method, and the results showed that the predictive accuracy was 100%. The genuine anisodamine tablets from 5 different manufacturing plants were distinguished by NIR spectroscopy using partial least squares discriminant analysis (PLS-DA) models based on interval principal component analysis (iPCA) method. And the results showed the recognition rate and rejection rate were 100% respectively. In conclusion, Raman spectroscopy and NIR spectroscopy combined with chemometrics are feasible and potential tools for rapid pharmaceutical tablet discrimination. Copyright © 2014 Elsevier B.V. All rights reserved.

Dissolution assessment of allopurinol immediate release tablets by near infrared spectroscopy.

PubMed

Smetiško, Jelena; Miljanić, Snežana

2017-10-25

The purpose of this study was to develop a NIR spectroscopic method for assessment of drug dissolution from allopurinol immediate release tablets. Thirty three different batches of allopurinol immediate release tablets containing constant amount of the active ingredient, but varying in excipients content and physical properties were introduced in a PLS calibration model. Correlating allopurinol dissolution reference values measured by the routinely used UV/Vis method, with the data extracted from the NIR spectra, values of correlation coefficient, bias, slope, residual prediction determination and root mean square error of prediction (0.9632, 0.328%, 1.001, 3.58, 3.75%) were evaluated. The obtained values implied that the NIR diffuse reflectance spectroscopy could serve as a faster and simpler alternative to the conventional dissolution procedure, even for the tablets with a very fast dissolution rate (>85% in 15minutes). Apart from the possibility of prediction of the allopurinol dissolution rate, the other multivariate technique, PCA, provided additional data on the non-chemical characteristics of the product, which could not be obtained from the reference dissolution values. Analysis on an independent set of samples confirmed that a difference between the UV/Vis reference method and the proposed NIR method was not significant. According to the presented results, the proposed NIR method may be suitable for practical application in routine analysis and for continuously monitoring the product's chemical and physical properties responsible for expected quality. Copyright © 2017 Elsevier B.V. All rights reserved.

[Rapid identification of potato cultivars using NIR-excited fluorescence and Raman spectroscopy].

PubMed

Dai, Fen; Bergholt, Mads Sylvest; Benjamin, Arnold Julian Vinoj; Hong, Tian-Sheng; Zhiwei, Huang

2014-03-01

Potato is one of the most important food in the world. Rapid and noninvasive identification of potato cultivars plays a important role in the better use of varieties. In this study, The identification ability of optical spectroscopy techniques, including near-infrared (NIR) Raman spectroscopy and NIR fluorescence spectroscopy, for invasive detection of potato cultivars was evaluated. A rapid NIR Raman spectroscopy system was applied to measure the composite Raman and NIR fluorescence spectroscopy of 3 different species of potatoes (98 samples in total) under 785 nm laser light excitation. Then pure Raman and NIR fluorescence spectroscopy were abstracted from the composite spectroscopy, respectively. At last, the partial least squares-discriminant analysis (PLS-DA) was utilized to analyze and classify Raman spectra of 3 different types of potatoes. All the samples were divided into two sets at random: the calibration set (74samples) and prediction set (24 samples), the model was validated using a leave-one-out, cross-validation method. The results showed that both the NIR-excited fluorescence spectra and pure Raman spectra could be used to identify three cultivars of potatoes. The fluorescence spectrum could distinguish the Favorita variety well (sensitivity: 1, specificity: 0.86 and accuracy: 0.92), but the result for Diamant (sensitivity: 0.75, specificity: 0.75 and accuracy: 0. 75) and Granola (sensitivity: 0.16, specificity: 0.89 and accuracy: 0.71) cultivars identification were a bit poorer. We demonstrated that Raman spectroscopy uncovered the main biochemical compositions contained in potato species, and provided a better classification sensitivity, specificity and accuracy (sensitivity: 1, specificity: 1 and accuracy: 1 for all 3 potato cultivars identification) among the three types of potatoes as compared to fluorescence spectroscopy.

UV / Visible / Near-Infrared Reflectance Models for the Rapid and Non-Destructive Prediction and Classification of Cotton Color and Physical Indices

USDA-ARS?s Scientific Manuscript database

High volume instrumentation (HVI), utilized in the cotton industry to determine the qualities and classifications of cotton fibers, is time consuming, and prone to day-to-day and location-to-location variations. UV / visible / NIR spectroscopy, a rapid and easy sampling technique, was investigated a...

Development of a hybrid proximal sensing method for rapid identification of petroleum contaminated soils.

PubMed

Chakraborty, Somsubhra; Weindorf, David C; Li, Bin; Ali Aldabaa, Abdalsamad Abdalsatar; Ghosh, Rakesh Kumar; Paul, Sathi; Nasim Ali, Md

2015-05-01

Using 108 petroleum contaminated soil samples, this pilot study proposed a new analytical approach of combining visible near-infrared diffuse reflectance spectroscopy (VisNIR DRS) and portable X-ray fluorescence spectrometry (PXRF) for rapid and improved quantification of soil petroleum contamination. Results indicated that an advanced fused model where VisNIR DRS spectra-based penalized spline regression (PSR) was used to predict total petroleum hydrocarbon followed by PXRF elemental data-based random forest regression was used to model the PSR residuals, it outperformed (R(2)=0.78, residual prediction deviation (RPD)=2.19) all other models tested, even producing better generalization than using VisNIR DRS alone (RPD's of 1.64, 1.86, and 1.96 for random forest, penalized spline regression, and partial least squares regression, respectively). Additionally, unsupervised principal component analysis using the PXRF+VisNIR DRS system qualitatively separated contaminated soils from control samples. Fusion of PXRF elemental data and VisNIR derivative spectra produced an optimized model for total petroleum hydrocarbon quantification in soils. Copyright © 2015 Elsevier B.V. All rights reserved.

[Effect of near infrared spectrum on the precision of PLS model for oil yield from oil shale].

PubMed

Wang, Zhi-Hong; Liu, Jie; Chen, Xiao-Chao; Sun, Yu-Yang; Yu, Yang; Lin, Jun

2012-10-01

It is impossible to use present measurement methods for the oil yield of oil shale to realize in-situ detection and these methods unable to meet the requirements of the oil shale resources exploration and exploitation. But in-situ oil yield analysis of oil shale can be achieved by the portable near infrared spectroscopy technique. There are different correlativities of NIR spectrum data formats and contents of sample components, and the different absorption specialities of sample components shows in different NIR spectral regions. So with the proportioning samples, the PLS modeling experiments were done by 3 formats (reflectance, absorbance and K-M function) and 4 regions of modeling spectrum, and the effect of NIR spectral format and region to the precision of PLS model for oil yield from oil shale was studied. The results show that the best data format is reflectance and the best modeling region is combination spectral range by PLS model method and proportioning samples. Therefore, the appropriate data format and the proper characteristic spectral region can increase the precision of PLS model for oil yield form oil shale.

Fire impact on forest soils evaluated using near-infrared spectroscopy and multivariate calibration.

PubMed

Vergnoux, A; Dupuy, N; Guiliano, M; Vennetier, M; Théraulaz, F; Doumenq, P

2009-11-15

The assessment of physico-chemical properties in forest soils affected by fires was evaluated using near infrared reflectance (NIR) spectroscopy coupled with chemometric methods. In order to describe the soil properties, measurements were taken of the total organic carbon on solid phase, the total nitrogen content, the organic carbon and the specific absorbences at 254 and 280 nm of humic substances, organic carbon in humic and fulvic acids, concentrations of NH(4)(+), Ca(2+), Mg(2+), K(+) and phosphorus in addition to NIR spectra. Then, a fire recurrence index was defined and calculated according to the different fires extents affecting soils. This calculation includes the occurrence of fires as well as the time elapsed since the last fire. This study shows that NIR spectroscopy could be considered as a tool for soil monitoring, particularly for the quantitative prediction of the total organic carbon, total nitrogen content, organic carbon in humic substances, concentrations of phosphorus, Mg(2+), Ca(2+) and NH(4)(+) and humic substances UVSA(254). Further validation in this field is necessary however, to try and make successful predictions of K(+), organic carbon in humic and fulvic acids and the humic substances UVSA(280). Moreover, NIR coupled with PLS can also be useful to predict the fire recurrence index in order to determine the spatial variability. Also this method can be used to map more or less burned areas and possibly to apply adequate rehabilitation techniques, like soil litter reconstitution with organic enrichments (industrial composts) or reforestation. Finally, the proposed recurrence index can be considered representative of the state of the soils.

Comparison of Attenuated Total Reflectance Mid-Infrared, Near Infrared, and 1H-Nuclear Magnetic Resonance Spectroscopies for the Determination of Coffee's Geographical Origin

PubMed Central

Caro Rodríguez, Diana; Arana, Victoria A.; Bernal, Andrés; Esseiva, Pierre

2017-01-01

The sensorial properties of Colombian coffee are renowned worldwide, which is reflected in its market value. This raises the threat of fraud by adulteration using coffee grains from other countries, thus creating a demand for robust and cost-effective methods for the determination of geographical origin of coffee samples. Spectroscopic techniques such as Nuclear Magnetic Resonance (NMR), near infrared (NIR), and mid-infrared (mIR) have arisen as strong candidates for the task. Although a body of work exists that reports on their individual performances, a faithful comparison has not been established yet. We evaluated the performance of 1H-NMR, Attenuated Total Reflectance mIR (ATR-mIR), and NIR applied to fraud detection in Colombian coffee. For each technique, we built classification models for discrimination by species (C. arabica versus C. canephora (or robusta)) and by origin (Colombia versus other C. arabica) using a common set of coffee samples. All techniques successfully discriminated samples by species, as expected. Regarding origin determination, ATR-mIR and 1H-NMR showed comparable capacity to discriminate Colombian coffee samples, while NIR fell short by comparison. In conclusion, ATR-mIR, a less common technique in the field of coffee adulteration and fraud detection, emerges as a strong candidate, faster and with lower cost compared to 1H-NMR and more discriminating compared to NIR. PMID:29201055

The use of near-infrared spectroscopy in understanding skeletal muscle physiology: recent developments.

PubMed

Ferrari, Marco; Muthalib, Makii; Quaresima, Valentina

2011-11-28

This article provides a snapshot of muscle near-infrared spectroscopy (NIRS) at the end of 2010 summarizing the recent literature, offering the present status and perspectives of the NIRS instrumentation and methods, describing the main NIRS studies on skeletal muscle physiology, posing open questions and outlining future directions. So far, different NIRS techniques (e.g. continuous-wave (CW) and spatially, time- and frequency-resolved spectroscopy) have been used for measuring muscle oxygenation during exercise. In the last four years, approximately 160 muscle NIRS articles have been published on different physiological aspects (primarily muscle oxygenation and haemodynamics) of several upper- and lower-limb muscle groups investigated by using mainly two-channel CW and spatially resolved spectroscopy commercial instruments. Unfortunately, in only 15 of these studies were the advantages of using multi-channel instruments exploited. There are still several open questions in the application of NIRS in muscle studies: (i) whether NIRS can be used in subjects with a large fat layer; (ii) the contribution of myoglobin desaturation to the NIRS signal during exercise; (iii) the effect of scattering changes during exercise; and (iv) the effect of changes in skin perfusion, particularly during prolonged exercise. Recommendations for instrumentation advancements and future muscle NIRS studies are provided.

Analysis of total oil and fatty acids composition by near infrared reflectance spectroscopy in edible nuts

NASA Astrophysics Data System (ADS)

Kandala, Chari V.; Sundaram, Jaya

2014-10-01

Near Infrared (NIR) Reflectance spectroscopy has established itself as an important tool in quantifying water and oil present in various food materials. It is rapid and nondestructive, easier to use, and does not require processing the samples with corrosive chemicals that would render them non-edible. Earlier, the samples had to be ground into powder form before making any measurements. With the development of new soft ware packages, NIR techniques could now be used in the analysis of intact grain and nuts. While most of the commercial instruments presently available work well with small grain size materials such as wheat and corn, the method present here is suitable for large kernel size products such as shelled or in-shell peanuts. Absorbance spectra were collected from 400 nm to 2500 nm using a NIR instrument. Average values of total oil contents (TOC) of peanut samples were determined by standard extraction methods, and fatty acids were determined using gas chromatography. Partial least square (PLS) analysis was performed on the calibration set of absorption spectra, and models were developed for prediction of total oil and fatty acids. The best model was selected based on the coefficient of determination (R2), Standard error of prediction (SEP) and residual percent deviation (RPD) values. Peanut samples analyzed showed RPD values greater than 5.0 for both absorbance and reflectance models and thus could be used for quality control and analysis. Ability to rapidly and nondestructively measure the TOC, and analyze the fatty acid composition, will be immensely useful in peanut varietal improvement as well as in the grading process of grain and nuts.

Use of photoacoustic mid-infrared spectroscopy to characterize soil properties and soil organic matter stability

NASA Astrophysics Data System (ADS)

Peltre, Clement; Bruun, Sander; Du, Changwen; Stoumann Jensen, Lars

2014-05-01

The persistence of soil organic matter (SOM) is recognized as a major ecosystem property due to its key role in earth carbon cycling, soil quality and ecosystem services. SOM stability is typically studied using biological methods such as measuring CO2-C evolution from microbial decomposition of SOM during laboratory incubation or by physical or chemical fractionation methods, allowing the separation of a labile fraction of SOM. However these methods are time consuming and there is still a need for developing reliable techniques to characterize SOM stability, providing both quantitative measurements and qualitative information, in order to improve our understanding of the mechanisms controlling SOM persistence. Several spectroscopic techniques have been used to characterize and predict SOM stability, such as near infrared reflectance spectroscopy (NIRS) and diffuse reflectance mid-infrared spectroscopy (DRIFT). The latter allows a proper identification of spectral regions corresponding to vibrations of specific molecular or functional groups associated with SOM lability. However, reflectance spectroscopy for soil analyses raises some difficulties related to the low reflectance of soils, and to the high influence of particle size. In the last three decades, the progresses in microphone sensitivity dramatically increased the performance of photoacoustic Fourier transform mid-infrared spectroscopy (FTIR-PAS). This technique offers benefits over reflectance spectroscopy techniques, because particle size and the level of sample reflectance have little effect of on the PAS signal, since FTIR-PAS is a direct absorption technique. Despite its high potential for soil analysis, only a limited number of studies have so far applied FTIR-PAS for soil characterization and its potential for determining SOM degradability still needs to be investigated. The objective of this study was to assess the potential of FTIR-PAS for the characterization of SOM decomposability during laboratory incubation and more classical soil parameters such as carbon and clay content for a range of 36 soils collected from various field experiments in Denmark. Partial least square (PLS) regression was used to correlate the collected FTIR-PAS spectra with the proportion of soil organic carbon mineralized after 34 weeks of incubation at 15° C and pF 2, taken as an indicator of the labile fraction of SOM. Results showed that it is possible to predict the labile fraction of SOM with FTIR PAS with similar accuracy as with NIRS (assessed in a previous study on the same soil set). FTIR-PAS offered the advantage over NIRS to allow identification of the chemical compounds positively or negatively correlated with the labile fraction of SOM. The band at 1612 cm-1 corresponding to polysaccharides, pectin and aromatic C=C was the band most positively correlated with labile SOM, which we attributed to the relative lability of fresh plant debris rich in polysaccharide and aromatic lignin. The band at 1560-1590 cm-1 assigned to N=H, C=N and aromatic C=C vibration was the band most negatively correlated with the labile fraction of SOM, confirming the abundance of nitrogenous and aromatic compounds in stabilized SOM. In conclusion, FTIR-PAS has proved to be a powerful tool to characterize the labile fraction of SOM, offering several benefits over reflectance spectroscopy techniques.

Effects of Subsetting by Parent Materials on Prediction of Soil Organic Matter Content in a Hilly Area Using Vis–NIR Spectroscopy

PubMed Central

Xu, Shengxiang; Shi, Xuezheng; Wang, Meiyan; Zhao, Yongcun

2016-01-01

Assessment and monitoring of soil organic matter (SOM) quality are important for understanding SOM dynamics and developing management practices that will enhance and maintain the productivity of agricultural soils. Visible and near-infrared (Vis–NIR) diffuse reflectance spectroscopy (350–2500 nm) has received increasing attention over the recent decades as a promising technique for SOM analysis. While heterogeneity of sample sets is one critical factor that complicates the prediction of soil properties from Vis–NIR spectra, a spectral library representing the local soil diversity needs to be constructed. The study area, covering a surface of 927 km2 and located in Yujiang County of Jiangsu Province, is characterized by a hilly area with different soil parent materials (e.g., red sandstone, shale, Quaternary red clay, and river alluvium). In total, 232 topsoil (0–20 cm) samples were collected for SOM analysis and scanned with a Vis–NIR spectrometer in the laboratory. Reflectance data were related to surface SOM content by means of a partial least square regression (PLSR) method and several data pre-processing techniques, such as first and second derivatives with a smoothing filter. The performance of the PLSR model was tested under different combinations of calibration/validation sets (global and local calibrations stratified according to parent materials). The results showed that the models based on the global calibrations can only make approximate predictions for SOM content (RMSE (root mean squared error) = 4.23–4.69 g kg−1; R2 (coefficient of determination) = 0.80–0.84; RPD (ratio of standard deviation to RMSE) = 2.19–2.44; RPIQ (ratio of performance to inter-quartile distance) = 2.88–3.08). Under the local calibrations, the individual PLSR models for each parent material improved SOM predictions (RMSE = 2.55–3.49 g kg−1; R2 = 0.87–0.93; RPD = 2.67–3.12; RPIQ = 3.15–4.02). Among the four different parent materials, the largest R2 and the smallest RMSE were observed for the shale soils, which had the lowest coefficient of variation (CV) values for clay (18.95%), free iron oxides (15.93%), and pH (1.04%). This demonstrates the importance of a practical subsetting strategy for the continued improvement of SOM prediction with Vis–NIR spectroscopy. PMID:26974821

Near infrared spectroscopy for body fat sensing in neonates: quantitative analysis by GAMOS simulations.

PubMed

Mustafa, Fatin Hamimi; Jones, Peter W; McEwan, Alistair L

2017-01-11

Under-nutrition in neonates is closely linked to low body fat percentage. Undernourished neonates are exposed to immediate mortality as well as unwanted health impacts in their later life including obesity and hypertension. One potential low cost approach for obtaining direct measurements of body fat is near-infrared (NIR) interactance. The aims of this study were to model the effect of varying volume fractions of melanin and water in skin over NIR spectra, and to define sensitivity of NIR reflection on changes of thickness of subcutaneous fat. GAMOS simulations were used to develop two single fat layer models and four complete skin models over a range of skin colour (only for four skin models) and hydration within a spectrum of 800-1100 nm. The thickness of the subcutaneous fat was set from 1 to 15 mm in 1 mm intervals in each model. Varying volume fractions of water in skin resulted minimal changes of NIR intensity at ranges of wavelengths from 890 to 940 nm and from 1010 to 1100 nm. Variation of the melanin volume in skin meanwhile was found to strongly influence the NIR intensity and sensitivity. The NIR sensitivities and NIR intensity over thickness of fat decreased from the Caucasian skin to African skin throughout the range of wavelengths. For the relationship between the NIR reflection and the thickness of subcutaneous fat, logarithmic relationship was obtained. The minimal changes of NIR intensity values at wavelengths within the ranges from 890 to 940 nm and from 1010 to 1100 nm to variation of volume fractions of water suggests that wavelengths within those two ranges are considered for use in measurement of body fat to solve the variation of hydration in neonates. The stronger influence of skin colour on NIR shows that the melanin effect needs to be corrected by an independent measurement or by a modeling approach. The logarithmic response obtained with higher sensitivity at the lower range of thickness of fat suggests that implementation of NIRS may be suited for detecting under-nutrition and monitoring nutritional interventions for malnutrition in neonates in resource-constrained communities.

Applications of single kernel conventional and hyperspectral imaging near infrared spectroscopy in cereals.

PubMed

Fox, Glen; Manley, Marena

2014-01-30

Single kernel (SK) near infrared (NIR) reflectance and transmittance technologies have been developed during the last two decades for a range of cereal grain physical quality and chemical traits as well as detecting and predicting levels of toxins produced by fungi. Challenges during the development of single kernel near infrared (SK-NIR) spectroscopy applications are modifications of existing NIR technology to present single kernels for scanning as well as modifying reference methods for the trait of interest. Numerous applications have been developed, and cover almost all cereals although most have been for key traits including moisture, protein, starch and oil in the globally important food grains, i.e. maize, wheat, rice and barley. An additional benefit in developing SK-NIR applications has been to demonstrate the value in sorting grain infected with a fungus or mycotoxins such as deoxynivalenol, fumonisins and aflatoxins. However, there is still a need to develop cost-effective technologies for high-speed sorting which can be used for small grain samples such as those from breeding programmes or commercial sorting; capable of sorting tonnes per hour. Development of SK-NIR technologies also includes standardisation of SK reference methods to analyse single kernels. For protein content, the use of the Dumas method would require minimal standardisation; for starch or oil content, considerable development would be required. SK-NIR, including the use of hyperspectral imaging, will improve our understanding of grain quality and the inherent variation in the range of a trait. In the area of food safety, this technology will benefit farmers, industry and consumers if it enables contaminated grain to be removed from the human food chain. © 2013 Society of Chemical Industry.

Optical monitoring of testicular torsion using a miniaturized near infrared spectroscopy sensor

NASA Astrophysics Data System (ADS)

Shadgan, Babak; Kajbafzadeh, Majid; Nigro, Mark; Kajbafzadeh, A. M.; Macnab, Andrew

2017-02-01

Background: Testicular torsion is an acute urological emergency occurring in children and adolescents. Accurate and fast diagnosis is important as the resulting ischemia can destroy the testis. Currently, Doppler ultrasound is the preferred diagnostic method. Ultrasound is not readily available in all centers which may delay surgical treatment. In this study, a rat model was used to examine the feasibility and sensitivity of using spatially-resolved near infrared spectroscopy (SR-NIRS) with a custom-made miniaturized optical sensor probe to detect and study changes in testicular hemodynamics and oxygenation during three degrees of induced testicular torsion, and after detorsion. Methods: Eight anesthetized rats (16 testes) were studied using SR-NIRS with the miniaturized optical probe applied directly onto the surface of the surgically exposed testis during 360, 720 and 1080 degrees of torsion followed by detorsion. Oxygenated, deoxygenated and total hemoglobin and TOI% were studied pre-and post-manipulations. Results: NIRS monitoring reflected acute testicular ischemia and hypoxia on induction of torsion, and tissue reperfusionreoxygenation after detorsion. Testicular torsion at 720 degrees induced the maximum observed degree of hypoxic changes. In all cases, rhythmic changes were observed in the NIRS signals before inducing torsion; these disappeared after applying 360 degrees of torsion and did not reappear after detorsion. Conclusion: This animal study indicates that SR-NIRS monitoring of the testes using a directly applied miniature sensor is a feasible and sensitive method to detect testicular ischemia and hypoxia immediately after torsion occurs, and testicular reperfusion upon detorsion. This study offers the potential for a SR-NIRS system with a miniaturized sensor to be explored further as a rapid, noninvasive, optical method for detecting testicular torsion in children.

Interferometric Near-Infrared Spectroscopy (iNIRS) for determination of optical and dynamical properties of turbid media

PubMed Central

Borycki, Dawid; Kholiqov, Oybek; Chong, Shau Poh; Srinivasan, Vivek J.

2016-01-01

We introduce and implement interferometric near-infrared spectroscopy (iNIRS), which simultaneously extracts optical and dynamical properties of turbid media through analysis of a spectral interference fringe pattern. The spectral interference fringe pattern is measured using a Mach-Zehnder interferometer with a frequency-swept narrow linewidth laser. Fourier analysis of the detected signal is used to determine time-of-flight (TOF)-resolved intensity, which is then analyzed over time to yield TOF-resolved intensity autocorrelations. This approach enables quantification of optical properties, which is not possible in conventional, continuous-wave near-infrared spectroscopy (NIRS). Furthermore, iNIRS quantifies scatterer motion based on TOF-resolved autocorrelations, which is a feature inaccessible by well-established diffuse correlation spectroscopy (DCS) techniques. We prove this by determining TOF-resolved intensity and temporal autocorrelations for light transmitted through diffusive fluid phantoms with optical thicknesses of up to 55 reduced mean free paths (approximately 120 scattering events). The TOF-resolved intensity is used to determine optical properties with time-resolved diffusion theory, while the TOF-resolved intensity autocorrelations are used to determine dynamics with diffusing wave spectroscopy. iNIRS advances the capabilities of diffuse optical methods and is suitable for in vivo tissue characterization. Moreover, iNIRS combines NIRS and DCS capabilities into a single modality. PMID:26832264

Phthalocyanine identification in paintings by reflectance spectroscopy. A laboratory and in situ study

NASA Astrophysics Data System (ADS)

Poldi, G.; Caglio, S.

2013-06-01

The importance of identifying pigments using non invasive (n.i.) analyses has gained increasing importance in the field of spectroscopy applied to art conservation and art studies. Among the large set of pigments synthesized and marketed during 20th century, surely phthalocyanine blue and green pigments occupy an important role in the field of painting (including restoration) and printing, thanks to their characteristics like brightness and fastness. This research focused on the most used phthalocyanine blue (PB15:1 and PB15:3) and green pigments (PG7), and on the possibility to identify these organic compounds using a methodology like reflectance spectroscopy in the UV, visible and near IR range (UV-vis-NIR RS), performed easily through portable instruments. Laboratory tests and three examples carried out on real paintings are discussed.

Surface plasmon resonance near-infrared spectroscopy.

PubMed

Ikehata, Akifumi; Itoh, Tamitake; Ozaki, Yukihiro

2004-11-01

Near-infrared (NIR) spectroscopy is ill-suited to microanalysis because of its low absorptivity. We have developed a highly sensitive detection method for NIR spectroscopy based on absorption-sensitive surface plasmon resonance (SPR). The newly named SPR-NIR spectroscopy, which may open the way for NIR spectroscopy in microanalysis and surface science, is realized by an attachment of the Kretschmann configuration equipped with a mechanism for fine angular adjustment of incident light. The angular sweep of incident light enables us to make a tuning of a SPR peak for an absorption band of sample medium. From the dependences of wavelength, incident angle, and thickness of a gold film on the intensity of the SPR peak, it has been found that the absorbance can be enhanced by approximately 100 times compared with the absorbance obtained without the gold film under optimum conditions. This article reports the details of the experimental setup and the characteristics of absorption-sensitive SPR in the NIR region, together with some experimental results obtained by using it.

Characterizing and Authenticating Montilla-Moriles PDO Vinegars Using Near Infrared Reflectance Spectroscopy (NIRS) Technology

PubMed Central

De la Haba, María-José; Arias, Mar; Ramírez, Pilar; López, María-Isabel; Sánchez, María-Teresa

2014-01-01

This study assessed the potential of near infrared (NIR) spectroscopy as a non-destructive method for characterizing Protected Designation of Origin (PDO) “Vinagres de Montilla-Moriles” wine vinegars and for classifying them as a function of the manufacturing process used. Three spectrophotometers were evaluated for this purpose: two monochromator instruments (Foss NIRSystems 6500 SY-I and Foss NIRSystems 6500 SY-II; spectral range 400–2,500 nm in both cases) and a diode-array instrument (Corona 45 VIS/NIR; spectral range 380–1,700 nm). A total of 70 samples were used to predict major chemical quality parameters (total acidity, fixed acidity, volatile acidity, pH, dry extract, ash, acetoin, methanol, total polyphenols, color (tonality and intensity), and alcohol content), and to construct models for the classification of vinegars as a function of the manufacturing method used. The results obtained indicate that this non-invasive technology can be used successfully by the vinegar industry and by PDO regulators for the routine analysis of vinegars in order to authenticate them and to detect potential fraud. Slightly better results were achieved with the two monochromator instruments. The findings also highlight the potential of these NIR instruments for predicting the manufacturing process used, this being of particular value for the industrial authentication of traditional wine vinegars. PMID:24561402

Monitoring brain temperature by time-resolved near-infrared spectroscopy: pilot study

NASA Astrophysics Data System (ADS)

Bakhsheshi, Mohammad Fazel; Diop, Mamadou; St. Lawrence, Keith; Lee, Ting-Yim

2014-05-01

Mild hypothermia (HT) is an effective neuroprotective strategy for a variety of acute brain injuries. However, the wide clinical adaptation of HT has been hampered by the lack of a reliable noninvasive method for measuring brain temperature, since core measurements have been shown to not always reflect brain temperature. The goal of this work was to develop a noninvasive optical technique for measuring brain temperature that exploits both the temperature dependency of water absorption and the high concentration of water in brain (80%-90%). Specifically, we demonstrate the potential of time-resolved near-infrared spectroscopy (TR-NIRS) to measure temperature in tissue-mimicking phantoms (in vitro) and deep brain tissue (in vivo) during heating and cooling, respectively. For deep brain tissue temperature monitoring, experiments were conducted on newborn piglets wherein hypothermia was induced by gradual whole body cooling. Brain temperature was concomitantly measured by TR-NIRS and a thermocouple probe implanted in the brain. Our proposed TR-NIRS method was able to measure the temperature of tissue-mimicking phantoms and brain tissues with a correlation of 0.82 and 0.66 to temperature measured with a thermometer, respectively. The mean difference between the TR-NIRS and thermometer measurements was 0.15°C±1.1°C for the in vitro experiments and 0.5°C±1.6°C for the in vivo measurements.

Real-time monitoring of a coffee roasting process with near infrared spectroscopy using multivariate statistical analysis: A feasibility study.

PubMed

Catelani, Tiago A; Santos, João Rodrigo; Páscoa, Ricardo N M J; Pezza, Leonardo; Pezza, Helena R; Lopes, João A

2018-03-01

This work proposes the use of near infrared (NIR) spectroscopy in diffuse reflectance mode and multivariate statistical process control (MSPC) based on principal component analysis (PCA) for real-time monitoring of the coffee roasting process. The main objective was the development of a MSPC methodology able to early detect disturbances to the roasting process resourcing to real-time acquisition of NIR spectra. A total of fifteen roasting batches were defined according to an experimental design to develop the MSPC models. This methodology was tested on a set of five batches where disturbances of different nature were imposed to simulate real faulty situations. Some of these batches were used to optimize the model while the remaining was used to test the methodology. A modelling strategy based on a time sliding window provided the best results in terms of distinguishing batches with and without disturbances, resourcing to typical MSPC charts: Hotelling's T 2 and squared predicted error statistics. A PCA model encompassing a time window of four minutes with three principal components was able to efficiently detect all disturbances assayed. NIR spectroscopy combined with the MSPC approach proved to be an adequate auxiliary tool for coffee roasters to detect faults in a conventional roasting process in real-time. Copyright © 2017 Elsevier B.V. All rights reserved.

In-line NIR spectroscopy for the understanding of polymer-drug interaction during pharmaceutical hot-melt extrusion.

PubMed

Saerens, Lien; Dierickx, Lien; Quinten, Thomas; Adriaensens, Peter; Carleer, Robert; Vervaet, Chris; Remon, Jean Paul; De Beer, Thomas

2012-05-01

The aim was to evaluate near-infrared spectroscopy for the in-line determination of the drug concentration, the polymer-drug solid-state behaviour and molecular interactions during hot-melt extrusion. Kollidon® SR was extruded with varying metoprolol tartrate (MPT) concentrations (20%, 30% and 40%) and monitored using NIR spectroscopy. A PLS model allowed drug concentration determination. The correlation between predicted and real MPT concentrations was good (R(2)=0.97). The predictive performance of the model was evaluated by the root mean square error of prediction, which was 1.54%. Kollidon® SR with 40% MPT was extruded at 105°C and 135°C to evaluate NIR spectroscopy for in-line polymer-drug solid-state characterisation. NIR spectra indicated the presence of amorphous MPT and hydrogen bonds between drug and polymer in the extrudates. More amorphous MPT and interactions could be found in the extrudates produced at 135°C than at 105°C. Raman spectroscopy, DSC and ATR FT-IR were used to confirm the NIR observations. Due to the instability of the formulation, only in-line Raman spectroscopy was an adequate confirmation tool. NIR spectroscopy is a potential PAT-tool for the in-line determination of API concentration and for the polymer-drug solid-state behaviour monitoring during pharmaceutical hot-melt extrusion. Copyright © 2012 Elsevier B.V. All rights reserved.

Near-infrared-excited confocal Raman spectroscopy advances in vivo diagnosis of cervical precancer.

PubMed

Duraipandian, Shiyamala; Zheng, Wei; Ng, Joseph; Low, Jeffrey J H; Ilancheran, Arunachalam; Huang, Zhiwei

2013-06-01

Raman spectroscopy is a unique optical technique that can probe the changes of vibrational modes of biomolecules associated with tissue premalignant transformation. This study evaluates the clinical utility of confocal Raman spectroscopy over near-infrared (NIR) autofluorescence (AF) spectroscopy and composite NIR AF/Raman spectroscopy for improving early diagnosis of cervical precancer in vivo at colposcopy. A rapid NIR Raman system coupled with a ball-lens fiber-optic confocal Raman probe was utilized for in vivo NIR AF/Raman spectral measurements of the cervix. A total of 1240 in vivo Raman spectra [normal (n=993), dysplasia (n=247)] were acquired from 84 cervical patients. Principal components analysis (PCA) and linear discriminant analysis (LDA) together with a leave-one-patient-out, cross-validation method were used to extract the diagnostic information associated with distinctive spectroscopic modalities. The diagnostic ability of confocal Raman spectroscopy was evaluated using the PCA-LDA model developed from the significant principal components (PCs) [i.e., PC4, 0.0023%; PC5, 0.00095%; PC8, 0.00022%, (p<0.05)], representing the primary tissue Raman features (e.g., 854, 937, 1095, 1253, 1311, 1445, and 1654 cm(-1)). Confocal Raman spectroscopy coupled with PCA-LDA modeling yielded the diagnostic accuracy of 84.1% (a sensitivity of 81.0% and a specificity of 87.1%) for in vivo discrimination of dysplastic cervix. The receiver operating characteristic curves further confirmed that the best classification was achieved using confocal Raman spectroscopy compared to the composite NIR AF/Raman spectroscopy or NIR AF spectroscopy alone. This study illustrates that confocal Raman spectroscopy has great potential to improve early diagnosis of cervical precancer in vivo during clinical colposcopy.

Chemometric compositional analysis of phenolic compounds in fermenting samples and wines using different infrared spectroscopy techniques.

PubMed

Aleixandre-Tudo, Jose Luis; Nieuwoudt, Helene; Aleixandre, Jose Luis; du Toit, Wessel

2018-01-01

The wine industry requires reliable methods for the quantification of phenolic compounds during the winemaking process. Infrared spectroscopy appears as a suitable technique for process control and monitoring. The ability of Fourier transform near infrared (FT-NIR), attenuated total reflectance mid infrared (ATR-MIR) and Fourier transform infrared (FT-IR) spectroscopies to predict compositional phenolic levels during red wine fermentation and aging was investigated. Prediction models containing a large number of samples collected over two vintages from several industrial fermenting tanks as well as wine samples covering a varying number of vintages were validated. FT-NIR appeared as the most accurate technique to predict the phenolic content. Although slightly less accurate models were observed, ATR-MIR and FT-IR can also be used for the prediction of the majority of phenolic measurements. Additionally, the slope and intercept test indicated a systematic error for the three spectroscopies which seems to be slightly more pronounced for HPLC generated phenolics data than for the spectrophotometric parameters. However, the results also showed that the predictions made with the three instruments are statistically comparable. The robustness of the prediction models was also investigated and discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

The application of Near-Infrared Reflectance Spectroscopy (NIRS) to detect melamine adulteration of soya bean meal.

PubMed

Haughey, Simon A; Graham, Stewart F; Cancouët, Emmanuelle; Elliott, Christopher T

2013-02-15

Soya bean products are used widely in the animal feed industry as a protein based feed ingredient and have been found to be adulterated with melamine. This was highlighted in the Chinese scandal of 2008. Dehulled soya (GM and non-GM), soya hulls and toasted soya were contaminated with melamine and spectra were generated using Near Infrared Reflectance Spectroscopy (NIRS). By applying chemometrics to the spectral data, excellent calibration models and prediction statistics were obtained. The coefficients of determination (R(2)) were found to be 0.89-0.99 depending on the mathematical algorithm used, the data pre-processing applied and the sample type used. The corresponding values for the root mean square error of calibration and prediction were found to be 0.081-0.276% and 0.134-0.368%, respectively, again depending on the chemometric treatment applied to the data and sample type. In addition, adopting a qualitative approach with the spectral data and applying PCA, it was possible to discriminate between the four samples types and also, by generation of Cooman's plots, possible to distinguish between adulterated and non-adulterated samples. Copyright © 2012 Elsevier Ltd. All rights reserved.

Combined data mining/NIR spectroscopy for purity assessment of lime juice

NASA Astrophysics Data System (ADS)

Shafiee, Sahameh; Minaei, Saeid

2018-06-01

This paper reports the data mining study on the NIR spectrum of lime juice samples to determine their purity (natural or synthetic). NIR spectra for 72 pure and synthetic lime juice samples were recorded in reflectance mode. Sample outliers were removed using PCA analysis. Different data mining techniques for feature selection (Genetic Algorithm (GA)) and classification (including the radial basis function (RBF) network, Support Vector Machine (SVM), and Random Forest (RF) tree) were employed. Based on the results, SVM proved to be the most accurate classifier as it achieved the highest accuracy (97%) using the raw spectrum information. The classifier accuracy dropped to 93% when selected feature vector by GA search method was applied as classifier input. It can be concluded that some relevant features which produce good performance with the SVM classifier are removed by feature selection. Also, reduced spectra using PCA do not show acceptable performance (total accuracy of 66% by RBFNN), which indicates that dimensional reduction methods such as PCA do not always lead to more accurate results. These findings demonstrate the potential of data mining combination with near-infrared spectroscopy for monitoring lime juice quality in terms of natural or synthetic nature.

Fruit Quality Evaluation Using Spectroscopy Technology: A Review

PubMed Central

Wang, Hailong; Peng, Jiyu; Xie, Chuanqi; Bao, Yidan; He, Yong

2015-01-01

An overview is presented with regard to applications of visible and near infrared (Vis/NIR) spectroscopy, multispectral imaging and hyperspectral imaging techniques for quality attributes measurement and variety discrimination of various fruit species, i.e., apple, orange, kiwifruit, peach, grape, strawberry, grape, jujube, banana, mango and others. Some commonly utilized chemometrics including pretreatment methods, variable selection methods, discriminant methods and calibration methods are briefly introduced. The comprehensive review of applications, which concentrates primarily on Vis/NIR spectroscopy, are arranged according to fruit species. Most of the applications are focused on variety discrimination or the measurement of soluble solids content (SSC), acidity and firmness, but also some measurements involving dry matter, vitamin C, polyphenols and pigments have been reported. The feasibility of different spectral modes, i.e., reflectance, interactance and transmittance, are discussed. Optimal variable selection methods and calibration methods for measuring different attributes of different fruit species are addressed. Special attention is paid to sample preparation and the influence of the environment. Areas where further investigation is needed and problems concerning model robustness and model transfer are identified. PMID:26007736

Utilization of visible to NIR light energy by Yb+3, Er+3 and Tm+3 doped BiVO4 for the photocatalytic degradation of methylene blue

NASA Astrophysics Data System (ADS)

Regmi, Chhabilal; Kshetri, Yuwaraj K.; Ray, Schindra Kumar; Pandey, Ramesh Prasad; Lee, Soo Wohn

2017-01-01

Lanthanide-doped BiVO4 semiconductors with efficient photocatalytic activities over a broad range of the solar light spectrum have been synthesized by the microwave hydrothermal method using ethylenediaminetetraacetic acid (EDTA). The structural, morphological, and optical properties of the as-synthesized samples were evaluated by Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), X-ray powder diffraction (XRD), Raman spectroscopy, FT-IR spectroscopy, UV-vis diffuse reflectance spectroscopy (DRS), and photoluminescence spectroscopy (PL). The chemical compositions were analyzed by X-ray photoelectron spectroscopy (XPS). The toxicity of the samples was measured using Mus musculus skin melanoma cells (B16-F10 (ATCC® CRL-6475™)) and were found to be nontoxic for human cells. The photocatalytic efficiency of the prepared samples was evaluated by methylene blue (MB) degradation. The best photocatalytic activity was shown by BiVO4 with 6:3:3 mol percentage of Yb+3:Er+3:Tm+3 in all solar light spectrum. The synthesized samples possess low band gap energy and a hollow structure suitable for the better photocatalytic activity. The observed NIR photoactivity supports that the upconversion mechanism is involved in the overall photocatalytic process. Therefore, this approach provides a better alternative upconversion material for integral solar light absorption.

Effects of slash-and-burn land management on soil spectral properties estimated with VIS-NIR-SWIR spectroscopy

NASA Astrophysics Data System (ADS)

Rosero-Vlasova, Olga Alexandra; Vlassova, Lidia; Rosero Tufiño, Pedro; Pérez-Cabello, Fernando; Montorio Llovería, Raquel

2017-04-01

Slash-and-burn land management is typical for low-income tropical countries, such as Ecuador. It involves conversion of forest into areas used for agriculture. At first trees are cut and the wood debris is burnt. After initial clearing, biomass burning is performed after each production cycle. Usually, cultivation cycles are followed by the fallow period. In the medium and long term, these practices have negative effect on soil fertility and there is the need for clearing more forest for agricultural use. This is one of the reasons for continuing deforestation with the consequent loss of biodiversity. Changes in physico-chemical properties due to periodic burning are accompanied by changes in soil spectral properties and can be determined using VIS-NIR-SWIR spectroscopy, which can be a cost-effective alternative for traditional methods of soil analysis. The purpose of the study is to assess the viability of VIS-NIR-SWIR spectroscopy for characterization of soils from land areas under slash-and-burn management system. Eighteen samples from soil surface layer were collected from two corn fields in the province of Los Rios, Ecuador, in September 2015. One of the areas has experienced six slash-and-burn cycles, while in the other the samples were collected at the end of the first corn cultivation cycle. Spectral measurements of sieved and air-dried samples were performed in the laboratory of the University of Zaragoza using ASD Fieldspec®4 spectroradiometer (350-2500nm spectral range) and ASD Illuminator Lamp as a light source. Statistically significant differences were observed between soil spectra of the samples from two soil groups. Reflectance of repeatedly burnt soils was 20% higher (mean value for the entire spectrum) for 65% of the samples, being especially important in VIS (>45%) and NIR ( 35%), probably due to the lower organic matter (OM) content. OM models built using Partial least Squares Regression demonstrated high predictive capacity (R2>0.8). Thus, the study confirms VIS-NIR-SWIR soil spectroscopy can be used as a tool for monitoring changes in soils in areas of slash-and-burn land management systems.

Non-invasive in situ identification and band assignments of diazepam, flunitrazepam and methadone hydrochloride with FT-near-infrared spectroscopy.

PubMed

Ali, Hassan Refat H

2011-03-20

Near-infrared spectroscopy (NIR) has evolved into an important rapid, direct and non-invasive technique in drugs analysis. In this study, the suitability of NIR spectroscopy to identify two benzodiazepine derivatives, diazepam and flunitrazepam, and a synthetic opiate, methadone hydrochloride, inside USP vials and probe the solid-state form of diazepam presents in tablets has been explored. The results show the potential of NIR spectroscopy for rapid, in situ and non-destructive identification of drugs. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Dissolution testing of isoniazid, rifampicin, pyrazinamide and ethambutol tablets using near-infrared spectroscopy (NIRS) and multivariate calibration.

PubMed

de Oliveira Neves, Ana Carolina; Soares, Gustavo Mesquita; de Morais, Stéphanie Cavalcante; da Costa, Fernanda Saadna Lopes; Porto, Dayanne Lopes; de Lima, Kássio Michell Gomes

2012-01-05

This work utilized the near-infrared spectroscopy (NIRS) and multivariate calibration to measure the percentage drug dissolution of four active pharmaceutical ingredients (APIs) (isoniazid, rifampicin, pyrazinamide and ethambutol) in finished pharmaceutical products produced in the Federal University of Rio Grande do Norte (Brazil). The conventional analytical method employed in quality control tests of the dissolution by the pharmaceutical industry is high-performance liquid chromatography (HPLC). The NIRS is a reliable method that offers important advantages for the large-scale production of tablets and for non-destructive analysis. NIR spectra of 38 samples (in triplicate) were measured using a Bomen FT-NIR 160 MB in the range 1100-2500nm. Each spectrum was the average of 50 scans obtained in the diffuse reflectance mode. The dissolution test, which was initially carried out in 900mL of 0.1N hydrochloric acid at 37±0.5°C, was used to determine the percentage a drug that dissolved from each tablet measured at the same time interval (45min) at pH 6.8. The measurement of the four API was performed by HPLC (Shimadzu, Japan) in the gradiente mode. The influence of various spectral pretreatments (Savitzky-Golay smoothing, Multiplicative Scatter Correction (MSC), and Savitzky-Golay derivatives) and multivariate analysis using the partial least squares (PLS) regression algorithm was calculated by the Unscrambler 9.8 (Camo) software. The correlation coefficient (R(2)) for the HPLC determination versus predicted values (NIRS) ranged from 0.88 to 0.98. The root-mean-square error of prediction (RMSEP) obtained from PLS models were 9.99%, 8.63%, 8.57% and 9.97% for isoniazid, rifampicin, ethambutol and pyrazinamide, respectively, indicating that the NIR method is an effective and non-destructive tool for measurement of drug dissolution from tablets. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.

Full scattering profile of tissues with elliptical cross sections

NASA Astrophysics Data System (ADS)

Duadi, H.; Feder, I.; Fixler, D.

2018-02-01

Light reflectance and transmission from soft tissue has been utilized in noninvasive clinical measurement devices such as the photoplethysmograph (PPG) and reflectance pulse oximeter. Most methods of near infrared (NIR) spectroscopy focus on the volume reflectance from a semi-infinite sample, while very few measure transmission. However, since PPG and pulse oximetry are usually measured on tissue such as earlobe, fingertip, lip and pinched tissue, we propose examining the full scattering profile (FSP), which is the angular distribution of exiting photons. The FSP provides more comprehensive information when measuring from a cylindrical tissue. In our work we discovered a unique point, that we named the iso-pathlength (IPL) point, which is not dependent on changes in the reduced scattering coefficient (µs'). This IPL point was observed both in Monte Carlo (MC) simulation and in experimental tissue mimicking phantoms. The angle corresponding to this IPL point depends only on the tissue geometry. In the case of cylindrical tissues this point linearly depends on the tissue diameter. Since the target tissues for clinically physiological measuring are not a perfect cylinder, in this work we will examine how the change in the tissue cross section geometry influences the FSP and the IPL point. We used a MC simulation to compare a circular to an elliptic tissue cross section. The IPL point can serve as a self-calibration point for optical tissue measurements such as NIR spectroscopy, PPG and pulse oximetery.

Measuring temperature induced phase change kinetics in subcutaneous fatty tissues using near infrared spectroscopy, magnetic resonance imaging and optical coherence tomography (Conference Presentation)

NASA Astrophysics Data System (ADS)

Sajjadi, Amir Y.; Carp, Stefan A.; Manstein, Dieter

2017-02-01

Monitoring phase transition in adipose tissue and formation of lipid crystals is important in Cryo-procedures such as cryosurgery or Selective Cryolipolysis (SC). In this work, we exploited a Near-Infrared Spectroscopy (NIRS) method to monitor the onset of fat freezing/melting. Concurrent measurements using frequency domain NIRS and MR Spectroscopy during cooling/heating were performed on an in vitro porcine skin sample with a thick subcutaneous fat layer in a human MR scanner. The NIRS probe was placed on the skin measuring the average optical scattering of the fatty layer. Two fiber optic temperature probes were inserted in the area of the MRS and NIRS measurements. To further investigate the microscopic features of the phase-transition, an identical cooling/heating procedure was replicated on the same fat tissue while being imaged by Optical Coherence Tomography. The temperature relationships of optical scattering, MRS peak characteristics and OCT reflection intensity were analyzed to find signatures related to the onset of phase transition. The optical scattering in the fatty tissues decreases during the heating and increases by cooling. However, there is an inflexion in the rate of change of the scattering while the phase transition happens in the fatty layer. The methylene fat peaks on the MR Spectrum are also shown to be broadened during the cooling. OCT intensity displays a sharp increase at the transition temperature. The results from multiple samples show two transition points around 5-10 ˚C (cooling) and 15-20 ˚C (heating) through all three methods, demonstrating that adipose tissue phase change can be monitored non-invasively.

Reflectance Photoplethysmography as Noninvasive Monitoring of Tissue Blood Perfusion.

PubMed

Abay, Tomas Ysehak; Kyriacou, Panayiotis A

2015-09-01

In the last decades, photoplethysmography (PPG) has been used as a noninvasive technique for monitoring arterial oxygen saturation by pulse oximetry (PO), whereas near-infrared spectroscopy (NIRS) has been employed for monitoring tissue blood perfusion. While NIRS offers more parameters to evaluate oxygen delivery and consumption in deep tissues, PO only assesses the state of oxygen delivery. For a broader assessment of blood perfusion, this paper explores the utilization of dual-wavelength PPG by using the pulsatile (ac) and continuous (dc) PPG for the estimation of arterial oxygen saturation (SpO2) by conventional PO. Additionally, the Beer-Lambert law is applied to the dc components only for the estimation of changes in deoxyhemoglobin (HHb), oxyhemoglobin (HbO2), and total hemoglobin (tHb) as in NIRS. The system was evaluated on the forearm of 21 healthy volunteers during induction of venous occlusion (VO) and total occlusion (TO). A reflectance PPG probe and NIRS sensor were applied above the brachioradialis, PO sensors were applied on the fingers, and all the signals were acquired simultaneously. While NIRS and forearm SpO2 indicated VO, SpO2 from the finger did not exhibit any significant drop from baseline. During TO, all the indexes indicated the change in blood perfusion. HHb, HbO2, and tHb changes estimated by PPG presented high correlation with the same parameters obtained by NIRS during VO (r(2) = 0.960, r(2) = 0.821, and r(2) = 0.974, respectively) and during TO (r(2) = 0.988, r(2) = 0.940, and r(2) = 0.938, respectively). The system demonstrated the ability to extract valuable information from PPG signals for a broader assessment of tissue blood perfusion.

Application of near infrared reflectance (NIR) spectroscopy to identify potential PSE meat.

PubMed

Li, Xiao; Feng, Fang; Gao, Runze; Wang, Lu; Qian, Ye; Li, Chunbao; Zhou, Guanghong

2016-07-01

Pale, soft and exudative (PSE) meat is a quality problem that causes a large economic loss to the pork industry. In the present work, near infrared (NIR) quantification and identification methods were used to investigate the feasibility of differentiating potential PSE meat from normal meat. NIR quantification models were developed to estimate meat pH and colour attributes (L*, a*, b*). Promising results were reported for prediction of muscle pH (R(2) CV  = 70.10%, RPDCV = 1.83) and L* (R(2) CV  = 77.18%, RPDCV = 1.91), but it is still hard to promote to practical application at this level. The Factorisation Method applied to NIR spectra could differentiate potential PSE meat from normal meat at 3 h post-mortem. Correlation analysis showed significant relationship between NIR data and LF-NMR T2 components that were indicative of water distribution and mobility in muscle. PSE meat had unconventionally faster energy metabolism than normal meat, which caused greater water mobility. NIR spectra coupled with the Factorisation Method could be a promising technology to identify potential PSE meat. The difference in the intensity of H2 O absorbance peaks between PSE and normal meat might be the basis of this identification method. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Diffuse reflectance spectroscopy of liver tissue

NASA Astrophysics Data System (ADS)

Reistad, Nina; Nilsson, Jan; Vilhelmsson Timmermand, Oskar; Sturesson, Christian; Andersson-Engels, Stefan

2015-06-01

Diffuse reflectance spectroscopy (DRS) with a fiber-optic contact probe is a cost-effective, rapid, and non-invasive optical method used to extract diagnosis information of tissue. By combining commercially available VIS- and NIR-spectrometers with various fiber-optic contact-probes, we have access to the full wavelength range from around 400 to 1600 nm. Using this flexible and portable spectroscopy system, we have acquired ex-vivo DRS-spectra from murine, porcine, and human liver tissue. For extracting the tissue optical properties from the measured spectra, we have employed and compared predictions from two models for light propagation in tissue, diffusion theory model (DT) and Monte Carlo simulations (MC). The focus in this work is on the capacity of this DRS-technique in discriminating metastatic tumor tissue from normal liver tissue as well as in assessing and characterizing damage to non-malignant liver tissue induced by preoperative chemotherapy for colorectal liver metastases.

Food Safety Evaluation Based on Near Infrared Spectroscopy and Imaging: A Review.

PubMed

Fu, Xiaping; Ying, Yibin

2016-08-17

In recent years, due to the increasing consciousness of food safety and human health, much progress has been made in developing rapid and nondestructive techniques for the evaluation of food hazards, food authentication, and traceability. Near infrared (NIR) spectroscopy and imaging techniques have gained wide acceptance in many fields because of their advantages over other analytical techniques. Following a brief introduction of NIR spectroscopy and imaging basics, this review mainly focuses on recent NIR spectroscopy and imaging applications for food safety evaluation, including (1) chemical hazards detection; (2) microbiological hazards detection; (3) physical hazards detection; (4) new technology-induced food safety concerns; and (5) food traceability. The review shows NIR spectroscopy and imaging to be effective tools that will play indispensable roles for food safety evaluation. In addition, on-line/real-time applications of these techniques promise to be a huge growth field in the near future.

Application of Near Infrared Reflectance Spectroscopy for Rapid and Non-Destructive Discrimination of Hulled Barley, Naked Barley, and Wheat Contaminated with Fusarium

PubMed Central

Lim, Jongguk; Kim, Giyoung; Mo, Changyeun; Oh, Kyoungmin; Kim, Geonseob; Ham, Hyeonheui; Kim, Seongmin; Kim, Moon S.

2018-01-01

Fusarium is a common fungal disease in grains that reduces the yield of barley and wheat. In this study, a near infrared reflectance spectroscopic technique was used with a statistical prediction model to rapidly and non-destructively discriminate grain samples contaminated with Fusarium. Reflectance spectra were acquired from hulled barley, naked barley, and wheat samples contaminated with Fusarium using near infrared reflectance (NIR) spectroscopy with a wavelength range of 1175–2170 nm. After measurement, the samples were cultured in a medium to discriminate contaminated samples. A partial least square discrimination analysis (PLS-DA) prediction model was developed using the acquired reflectance spectra and the culture results. The correct classification rate (CCR) of Fusarium for the hulled barley, naked barley, and wheat samples developed using raw spectra was 98% or higher. The accuracy of discrimination prediction improved when second and third-order derivative pretreatments were applied. The grains contaminated with Fusarium could be rapidly discriminated using spectroscopy technology and a PLS-DA discrimination model, and the potential of the non-destructive discrimination method could be verified. PMID:29301319

Parietal and temporal activity during a multimodal dance video game: an fNIRS study.

PubMed

Tachibana, Atsumichi; Noah, J Adam; Bronner, Shaw; Ono, Yumie; Onozuka, Minoru

2011-10-03

Using functional near infrared spectroscopy (fNIRS) we studied how playing a dance video game employs coordinated activation of sensory-motor integration centers of the superior parietal lobe (SPL) and superior temporal gyrus (STG). Subjects played a dance video game, in a block design with 30s of activity alternating with 30s of rest, while changes in oxy-hemoglobin (oxy-Hb) levels were continuously measured. The game was modified to compare difficult (4-arrow), simple (2-arrow), and stepping conditions. Oxy-Hb levels were greatest with increased task difficulty. The quick-onset, trapezoidal time-course increase in SPL oxy-Hb levels reflected the on-off neuronal response of spatial orienting and rhythmic motor timing that were required during the activity. Slow-onset, bell-shaped increases in oxy-Hb levels observed in STG suggested the gradually increasing load of directing multisensory information to downstream processing centers associated with motor behavior and control. Differences in temporal relationships of SPL and STG oxy-Hb concentration levels may reflect the functional roles of these brain structures during the task period. NIRS permits insights into temporal relationships of cortical hemodynamics during real motor tasks. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Nutritional evaluation of commercial dry dog foods by near infrared reflectance spectroscopy.

PubMed

Alomar, D; Hodgkinson, S; Abarzúa, D; Fuchslocher, R; Alvarado, C; Rosales, E

2006-06-01

Near infrared reflectance spectroscopy (NIRS) was used to predict the nutritional value of dog foods sold in Chile. Fifty-nine dry foods for adult and growing dogs were collected, ground and scanned across the visible/NIR range and subsequently analysed for dry matter (DM), crude protein (CP), crude fibre (CF), total fat, linoleic acid, gross energy (GE), estimated metabolizable energy (ME) and several amino acids and minerals. Calibration equations were developed by modified partial least squares regression, and tested by cross-validation. Standard error of cross validation (SE(CV)) and coefficient of determination of cross validation (SE(CV)) were used to select best equations. Equations with good predicting accuracy were obtained for DM, CF, CP, GE and fat. Corresponding values for and SE(CV) were 0.96 and 1.7 g/kg, 0.91 and 3.1 g/kg, 0.99 and 5.0 g/kg, 0.93 and 0.26 MJ/kg, 0.89 and 12.4 g/kg. Several amino acids were also well predicted, such as arginine, leucine, isoleucine, phenylalanine-tyrosine (combined), threonine and valine, with values for and SE(CV) (g/kg) of 0.89 and 0.9, 0.94 and 1.3, 0.91 and 0.5, 0.95 and 0.9, 0.91 and 0.5, 0.93 and 0.5. Intermediate values, appropriate for ranking purposes, were obtained for ME, histidine, lysine and methionine-cysteine. Tryptophan, minerals or linoleic acid were not acceptably predicted, irrespective of the mathematical treatment applied. It is concluded that NIR can be successfully used to predict important nutritional characteristics of commercial dog foods.

Reflectance spectroscopy: a tool for predicting the risk of iron chlorosis in soils

NASA Astrophysics Data System (ADS)

Cañasveras, J. C.; Barrón, V.; Del Campillo, M. C.; Viscarra Rossel, R. A.

2012-04-01

Chlorosis due to iron (Fe) deficiency is the most important nutritional problem a plant can have in calcareous soils. The most characteristic symptom of Fe chlorosis is internervial yellowing in the youngest leaves due to a lack of chlorophyll caused by a disorder in Fe nutrition. Fe chlorosis is related with calcium carbonate equivalent (CCE), clay content and Fe extracted with oxalate (Feo). The conventional technique for determining these properties and others, based on laboratory analysis, are time-consuming and costly. Reflectance spectroscopy (RS) is a rapid, non-destructive, less expensive alternative tool that can be used to enhance or replace conventional methods of soil analysis. The aim of this work was to assess the usefulness of RS for the determination of some properties of Mediterranean soils including clay content, CCE, Feo, cation exchange capacity (CEC), organic matter (OM) and pHw, with emphasis on those with a specially marked influence on the risk of Fe chlorosis. To this end, we used partial least-squares regression (PLS) to construct calibration models, leave-one-out cross-validation and an independent validation set. Our results testify to the usefulness of qualitative soil interpretations based on the variable importance for projection (VIP) as derived by PLS decomposition. The accuracy of predictions in each of the Vis-NIR, MIR and combined spectral regions differed considerably between properties. The R2adj and root mean square error (RMSE) for the external validation predictions were as follows: 0.83 and 37 mg kg-1 for clay content in the Vis-NIR-MIR range; 0.99 and 25 mg kg-1 for CCE, 0.80 and 0.1 mg kg-1 for Feo in the MIR range; 0.93 and 3 cmolc kg-1 for CEC in the Vis-NIR range; 0.87 and 2 mg kg-1 for OM in the Vis-NIR-MIR range, 0.61 and 0.2 for pHw in the MIR range. These results testify to the potential of RS in the Vis, NIR and MIR ranges for efficient soil analysis, the acquisition of soil information and the assessment of the risk of Fe chlorosis in soils.

A novel approach to comparing reproductive stage serum profiles in mares using near infrared spectroscopy (NIR) and aquaphotomics

USDA-ARS?s Scientific Manuscript database

The capability of near infrared spectroscopy (NIR) to detect biomolecules in aqueous solutions, a sub-field of NIR called Aquaphotomics, has yet to be fully explored. Aquaphotomics references water absorbance patterns and wavelength shifts in the 1st overtone of the water spectrum as they change pat...

NIRS-SPM: statistical parametric mapping for near infrared spectroscopy

NASA Astrophysics Data System (ADS)

Tak, Sungho; Jang, Kwang Eun; Jung, Jinwook; Jang, Jaeduck; Jeong, Yong; Ye, Jong Chul

2008-02-01

Even though there exists a powerful statistical parametric mapping (SPM) tool for fMRI, similar public domain tools are not available for near infrared spectroscopy (NIRS). In this paper, we describe a new public domain statistical toolbox called NIRS-SPM for quantitative analysis of NIRS signals. Specifically, NIRS-SPM statistically analyzes the NIRS data using GLM and makes inference as the excursion probability which comes from the random field that are interpolated from the sparse measurement. In order to obtain correct inference, NIRS-SPM offers the pre-coloring and pre-whitening method for temporal correlation estimation. For simultaneous recording NIRS signal with fMRI, the spatial mapping between fMRI image and real coordinate in 3-D digitizer is estimated using Horn's algorithm. These powerful tools allows us the super-resolution localization of the brain activation which is not possible using the conventional NIRS analysis tools.

Time- and Space-Resolved Spectroscopic Investigation on Pi-Conjugated Nanostructures - 2

DTIC Science & Technology

2016-01-12

15. SUBJECT TERMS Materials Characterization, Materials Chemistry, Nonlinear Optical Materials, Spectroscopy 16. SECURITY CLASSIFICATION...nanostructures will translate into new ground-breaking developments that not only allow the structure-property relationships to be probed in greater detail... spectroscopy . I. Experimental method 1. Steady-state Spectroscopy - UV-Vis-NIR Absorption & Emission Steady-state Spectroscopy - NIR

Advances in R&D in near-infrared spectroscopy in Japan

NASA Astrophysics Data System (ADS)

Kawano, Sumio; Iwamoto, Mutsuo

1991-02-01

More than 20 years ago when Mr. K. H. Norris firstly introduced the near infrared spectroscopy (NIRS) as a powerful technology in the field of composition analysis of cereals those who were interested in the area of classical spectroscopy would not like to recognize its potential. This tendency still remains at present however it leaves no room for doubt that from viewpoints of applied spectroscopy the NIRS has consolidated its position. From a viewpoint of NIRS application in the field of nondestructive or non invasive measuring techniques history of this technology is only the last decade in Japan. However since the technology was firstly introduced to composition analysis of agricultural commodities in the same manner as in other countries R and D have been growing more actively in diversified fields such as agriculture and industry as well as medical science. In addition the NIRS technology are becoming of general interest by combining other techniques to create various hyphenated instrumentations such as FTNIR MCFTNIR NIRCT and NIR-NMR. In this paper new trends of R D on NIR spectroscopy which are being conducted in Japan will be reviewed. 2. S1JMMARY OF PRESENT R D ON NIRS IN JAPAN NIRS applications reported in the last 3 years are summarized in Table 1. Table 1 Applications of NIRS in Japan Application for Agriculture Taste evaluation of rice and coffee Determination of chemical compositions rice for breeding Determination of chemical compositions in tea Determination of sugar contents in intact peaches Japanese pears Satsuma oranges and apples Determination of sugars and acids in intact tomatoes Determination of forage composition Application for Industry Analysis of state of water in foods Application of analyzing Maillard Reaction''s Process Pattern recognition of NIR spectra as related to process control of roasting coffee beans Quality control of tea processing Determination of moisture content of Surimi products 2 / SPIE Vol. 1379 Optics in Agriculture (1990)

[Application of near infrared reflectance spectroscopy to predict meat chemical compositions: a review].

PubMed

Tao, Lin-Li; Yang, Xiu-Juan; Deng, Jun-Ming; Zhang, Xi

2013-11-01

In contrast to conventional methods for the determination of meat chemical composition, near infrared reflectance spectroscopy enables rapid, simple, secure and simultaneous assessment of numerous meat properties. The present review focuses on the use of near infrared reflectance spectroscopy to predict meat chemical compositions. The potential of near infrared reflectance spectroscopy to predict crude protein, intramuscular fat, fatty acid, moisture, ash, myoglobin and collagen of beef, pork, chicken and lamb is reviewed. This paper discusses existing questions and reasons in the current research. According to the published results, although published results vary considerably, they suggest that near-infrared reflectance spectroscopy shows a great potential to replace the expensive and time-consuming chemical analysis of meat composition. In particular, under commercial conditions where simultaneous measurements of different chemical components are required, near infrared reflectance spectroscopy is expected to be the method of choice. The majority of studies selected feature-related wavelengths using principal components regression, developed the calibration model using partial least squares and modified partial least squares, and estimated the prediction accuracy by means of cross-validation using the same sample set previously used for the calibration. Meat fatty acid composition predicted by near-infrared spectroscopy and non-destructive prediction and visualization of chemical composition in meat using near-infrared hyperspectral imaging and multivariate regression are the hot studying field now. On the other hand, near infrared reflectance spectroscopy shows great difference for predicting different attributes of meat quality which are closely related to the selection of calibration sample set, preprocessing of near-infrared spectroscopy and modeling approach. Sample preparation also has an important effect on the reliability of NIR prediction; in particular, lack of homogeneity of the meat samples influenced the accuracy of estimation of chemical components. In general the predicting results of intramuscular fat, fatty acid and moisture are best, the predicting results of crude protein and myoglobin are better, while the predicting results of ash and collagen are less accurate.

Greater contribution of cerebral than extracerebral hemodynamics to near-infrared spectroscopy signals for functional activation and resting-state connectivity in infants.

PubMed

Funane, Tsukasa; Homae, Fumitaka; Watanabe, Hama; Kiguchi, Masashi; Taga, Gentaro

2014-10-01

While near-infrared spectroscopy (NIRS) has been increasingly applied to neuroimaging and functional connectivity studies in infants, it has not been quantitatively examined as to what extent the deep tissue (such as cerebral tissue) as opposed to shallow tissue (such as scalp), contributes to NIRS signals measured in infants. A method for separating the effects of deep- and shallow-tissue layers was applied to data of nine sleeping three-month-old infants who had been exposed to 3-s speech sounds or silence (i.e., resting state) and whose hemodynamic changes over their bilateral temporal cortices had been measured by using an NIRS system with multiple source-detector (S-D) distances. The deep-layer contribution was found to be large during resting [67% at S-D 20 mm, 78% at S-D 30 mm for oxygenated hemoglobin (oxy-Hb)] as well as during the speech condition (72% at S-D 20 mm, 82% at S-D 30 mm for oxy-Hb). A left-right connectivity analysis showed that correlation coefficients between left and right channels did not differ between original- and deep-layer signals under no-stimulus conditions and that of original- and deep-layer signals were larger than those of the shallow layer. These results suggest that NIRS signals obtained in infants with appropriate S-D distances largely reflected cerebral hemodynamic changes.

Greater contribution of cerebral than extracerebral hemodynamics to near-infrared spectroscopy signals for functional activation and resting-state connectivity in infants

PubMed Central

Funane, Tsukasa; Homae, Fumitaka; Watanabe, Hama; Kiguchi, Masashi; Taga, Gentaro

2014-01-01

Abstract. While near-infrared spectroscopy (NIRS) has been increasingly applied to neuroimaging and functional connectivity studies in infants, it has not been quantitatively examined as to what extent the deep tissue (such as cerebral tissue) as opposed to shallow tissue (such as scalp), contributes to NIRS signals measured in infants. A method for separating the effects of deep- and shallow-tissue layers was applied to data of nine sleeping three-month-old infants who had been exposed to 3-s speech sounds or silence (i.e., resting state) and whose hemodynamic changes over their bilateral temporal cortices had been measured by using an NIRS system with multiple source-detector (S-D) distances. The deep-layer contribution was found to be large during resting [67% at S-D 20 mm, 78% at S-D 30 mm for oxygenated hemoglobin (oxy-Hb)] as well as during the speech condition (72% at S-D 20 mm, 82% at S-D 30 mm for oxy-Hb). A left-right connectivity analysis showed that correlation coefficients between left and right channels did not differ between original- and deep-layer signals under no-stimulus conditions and that of original- and deep-layer signals were larger than those of the shallow layer. These results suggest that NIRS signals obtained in infants with appropriate S-D distances largely reflected cerebral hemodynamic changes. PMID:26157977

Predicting herbivore faecal nitrogen using a multispecies near-infrared reflectance spectroscopy calibration.

PubMed

Villamuelas, Miriam; Serrano, Emmanuel; Espunyes, Johan; Fernández, Néstor; López-Olvera, Jorge R; Garel, Mathieu; Santos, João; Parra-Aguado, María Ángeles; Ramanzin, Maurizio; Fernández-Aguilar, Xavier; Colom-Cadena, Andreu; Marco, Ignasi; Lavín, Santiago; Bartolomé, Jordi; Albanell, Elena

2017-01-01

Optimal management of free-ranging herbivores requires the accurate assessment of an animal's nutritional status. For this purpose 'near-infrared reflectance spectroscopy' (NIRS) is very useful, especially when nutritional assessment is done through faecal indicators such as faecal nitrogen (FN). In order to perform an NIRS calibration, the default protocol recommends starting by generating an initial equation based on at least 50-75 samples from the given species. Although this protocol optimises prediction accuracy, it limits the use of NIRS with rare or endangered species where sample sizes are often small. To overcome this limitation we tested a single NIRS equation (i.e., multispecies calibration) to predict FN in herbivores. Firstly, we used five herbivore species with highly contrasting digestive physiologies to build monospecies and multispecies calibrations, namely horse, sheep, Pyrenean chamois, red deer and European rabbit. Secondly, the equation accuracy was evaluated by two procedures using: (1) an external validation with samples from the same species, which were not used in the calibration process; and (2) samples from different ungulate species, specifically Alpine ibex, domestic goat, European mouflon, roe deer and cattle. The multispecies equation was highly accurate in terms of the coefficient of determination for calibration R2 = 0.98, standard error of validation SECV = 0.10, standard error of external validation SEP = 0.12, ratio of performance to deviation RPD = 5.3, and range error of prediction RER = 28.4. The accuracy of the multispecies equation to predict other herbivore species was also satisfactory (R2 > 0.86, SEP < 0.27, RPD > 2.6, and RER > 8.1). Lastly, the agreement between multi- and monospecies calibrations was also confirmed by the Bland-Altman method. In conclusion, our single multispecies equation can be used as a reliable, cost-effective, easy and powerful analytical method to assess FN in a wide range of herbivore species.

Identification of Medicinal Mugua Origin by Near Infrared Spectroscopy Combined with Partial Least-squares Discriminant Analysis.

PubMed

Han, Bangxing; Peng, Huasheng; Yan, Hui

2016-01-01

Mugua is a common Chinese herbal medicine. There are three main medicinal origin places in China, Xuancheng City Anhui Province, Qijiang District Chongqing City, Yichang City, Hubei Province, and suitable for food origin places Linyi City Shandong Province. To construct a qualitative analytical method to identify the origin of medicinal Mugua by near infrared spectroscopy (NIRS). Partial least squares discriminant analysis (PLSDA) model was established after the Mugua derived from five different origins were preprocessed by the original spectrum. Moreover, the hierarchical cluster analysis was performed. The result showed that PLSDA model was established. According to the relationship of the origins-related important score and wavenumber, and K-mean cluster analysis, the Muguas derived from different origins were effectively identified. NIRS technology can quickly and accurately identify the origin of Mugua, provide a new method and technology for the identification of Chinese medicinal materials. After preprocessed by D1+autoscale, more peaks were increased in the preprocessed Mugua in the near infrared spectrumFive latent variable scores could reflect the information related to the origin place of MuguaOrigins of Mugua were well-distinguished according to K. mean value clustering analysis. Abbreviations used: TCM: Traditional Chinese Medicine, NIRS: Near infrared spectroscopy, SG: Savitzky-Golay smoothness, D1: First derivative, D2: Second derivative, SNV: Standard normal variable transformation, MSC: Multiplicative scatter correction, PLSDA: Partial least squares discriminant analysis, LV: Latent variable, VIP scores: Important score.

In-vivo quantitative measurement of tissue oxygen saturation of human webbing using a transmission type continuous-wave near-infrared spectroscopy

NASA Astrophysics Data System (ADS)

Aizimu, Tuerxun; Adachi, Makoto; Nakano, Kazuya; Ohnishi, Takashi; Nakaguchi, Toshiya; Takahashi, Nozomi; Nakada, Taka-aki; Oda, Shigeto; Haneishi, Hideaki

2018-02-01

Near-infrared spectroscopy (NIRS) is a noninvasive method for monitoring tissue oxygen saturation (StO2). Many commercial NIRS devices are presently available. However, the precision of those devices is relatively poor because they are using the reflectance-model with which it is difficult to obtain the blood volume and other unchanged components of the tissue. Human webbing is a thin part of the hand and suitable to measure spectral transmittance. In this paper, we present a method for measuring StO2 of human webbing from a transmissive continuous-wave nearinfrared spectroscopy (CW-NIRS) data. The method is based on the modified Beer-Lambert law (MBL) and it consists of two steps. In the first step, we give a pressure to the upstream region of the measurement point to perturb the concentration of deoxy- and oxy-hemoglobin as remaining the other components and measure the spectral signals. From the measured data, spectral absorbance due to the components other than hemoglobin is calculated. In the second step, spectral measurement is performed at arbitrary time instance and the spectral absorbance obtained in the step 1 is subtracted from the measured absorbance. The tissue oxygen saturation (StO2) is estimated from the remained data. The method was evaluated on an arterial occlusion test (AOT) and a venous occlusion test (VOT). In the evaluation experiment, we confirmed that reasonable values of StO2 were obtained by the proposed method.

Thermal consequences of colour and near-infrared reflectance.

PubMed

Stuart-Fox, Devi; Newton, Elizabeth; Clusella-Trullas, Susana

2017-07-05

The importance of colour for temperature regulation in animals remains controversial. Colour can affect an animal's temperature because all else being equal, dark surfaces absorb more solar energy than do light surfaces, and that energy is converted into heat. However, in reality, the relationship between colour and thermoregulation is complex and varied because it depends on environmental conditions and the physical properties, behaviour and physiology of the animal. Furthermore, the thermal effects of colour depend as much on absorptance of near-infrared ((NIR), 700-2500 nm) as visible (300-700 nm) wavelengths of direct sunlight; yet the NIR is very rarely considered or measured. The few available data on NIR reflectance in animals indicate that the visible reflectance is often a poor predictor of NIR reflectance. Adaptive variation in animal coloration (visible reflectance) reflects a compromise between multiple competing functions such as camouflage, signalling and thermoregulation. By contrast, adaptive variation in NIR reflectance should primarily reflect thermoregulatory requirements because animal visual systems are generally insensitive to NIR wavelengths. Here, we assess evidence and identify key research questions regarding the thermoregulatory function of animal coloration, and specifically consider evidence for adaptive variation in NIR reflectance.This article is part of the themed issue 'Animal coloration: production, perception, function and application'. © 2017 The Author(s).

Clinical application of near-infrared spectroscopy in patients with traumatic brain injury: a review of the progress of the field.

PubMed

Sen, Anish N; Gopinath, Shankar P; Robertson, Claudia S

2016-07-01

Near-infrared spectroscopy (NIRS) is a technique by which the interaction between light in the near-infrared spectrum and matter can be quantitatively measured to provide information about the particular chromophore. Study into the clinical application of NIRS for traumatic brain injury (TBI) began in the 1990s with early reports of the ability to detect intracranial hematomas using NIRS. We highlight the advances in clinical applications of NIRS over the past two decades as they relate to TBI. We discuss recent studies evaluating NIRS techniques for intracranial hematoma detection, followed by the clinical application of NIRS in intracranial pressure and brain oxygenation measurement, and conclude with a summary of potential future uses of NIRS in TBI patient management.

A Brief Review on the Use of Functional Near-Infrared Spectroscopy (fNIRS) for Language Imaging Studies in Human Newborns and Adults

ERIC Educational Resources Information Center

Quaresima, Valentina; Bisconti, Silvia; Ferrari, Marco

2012-01-01

Upon stimulation, real time maps of cortical hemodynamic responses can be obtained by non-invasive functional near-infrared spectroscopy (fNIRS) which measures changes in oxygenated and deoxygenated hemoglobin after positioning multiple sources and detectors over the human scalp. The current commercially available transportable fNIRS systems have…

Study on fast measurement of sugar content of yogurt using Vis/NIR spectroscopy techniques

NASA Astrophysics Data System (ADS)

He, Yong; Feng, Shuijuan; Wu, Di; Li, Xiaoli

2006-09-01

In order to measuring the sugar content of yogurt rapidly, a fast measurement of sugar content of yogurt using Vis/NIR-spectroscopy techniques was established. 25 samples selected separately from five different brands of yogurt were measured by Vis/NIR-spectroscopy. The sugar content of yogurt on positions scanned by spectrum were measured by a sugar content meter. The mathematical model between sugar content and Vis/NIR spectral measurements was established and developed based on partial least squares (PLS). The correlation coefficient of sugar content based on PLS model is more than 0.894, and standard error of calibration (SEC) is 0.356, standard error of prediction (SEP) is 0.389. Through predicting the sugar content quantitatively of 35 samples of yogurt from 5 different brands, the correlation coefficient between predictive value and measured value of those samples is more than 0.934. The results show the good to excellent prediction performance. The Vis/NIR spectroscopy technique had significantly greater accuracy for determining the sugar content. It was concluded that the Vis/NIRS measurement technique seems reliable to assess the fast measurement of sugar content of yogurt, and a new method for the measurement of sugar content of yogurt was established.

Rapid detection of kernel rots and mycotoxins in maize by near-infrared reflectance spectroscopy.

PubMed

Berardo, Nicola; Pisacane, Vincenza; Battilani, Paola; Scandolara, Andrea; Pietri, Amedeo; Marocco, Adriano

2005-10-19

Near-infrared (NIR) spectroscopy is a practical spectroscopic procedure for the detection of organic compounds in matter. It is particularly useful because of its nondestructiveness, accuracy, rapid response, and easy operation. This work assesses the applicability of NIR for the rapid identification of micotoxigenic fungi and their toxic metabolites produced in naturally and artificially contaminated products. Two hundred and eighty maize samples were collected both from naturally contaminated maize crops grown in 16 areas in north-central Italy and from ears artificially inoculated with Fusarium verticillioides. All samples were analyzed for fungi infection, ergosterol, and fumonisin B1 content. The results obtained indicated that NIR could accurately predict the incidence of kernels infected by fungi, and by F. verticillioides in particular, as well as the quantity of ergosterol and fumonisin B1 in the meal. The statistics of the calibration and of the cross-validation for mold infection and for ergosterol and fumonisin B1 contents were significant. The best predictive ability for the percentage of global fungal infection and F. verticillioides was obtained using a calibration model utilizing maize kernels (r2 = 0.75 and SECV = 7.43) and maize meals (r2 = 0.79 and SECV = 10.95), respectively. This predictive performance was confirmed by the scatter plot of measured F. verticillioides infection versus NIR-predicted values in maize kernel samples (r2 = 0.80). The NIR methodology can be applied for monitoring mold contamination in postharvest maize, in particular F. verticilliodes and fumonisin presence, to distinguish contaminated lots from clean ones, and to avoid cross-contamination with other material during storage and may become a powerful tool for monitoring the safety of the food supply.

Beer fermentation: monitoring of process parameters by FT-NIR and multivariate data analysis.

PubMed

Grassi, Silvia; Amigo, José Manuel; Lyndgaard, Christian Bøge; Foschino, Roberto; Casiraghi, Ernestina

2014-07-15

This work investigates the capability of Fourier-Transform near infrared (FT-NIR) spectroscopy to monitor and assess process parameters in beer fermentation at different operative conditions. For this purpose, the fermentation of wort with two different yeast strains and at different temperatures was monitored for nine days by FT-NIR. To correlate the collected spectra with °Brix, pH and biomass, different multivariate data methodologies were applied. Principal component analysis (PCA), partial least squares (PLS) and locally weighted regression (LWR) were used to assess the relationship between FT-NIR spectra and the abovementioned process parameters that define the beer fermentation. The accuracy and robustness of the obtained results clearly show the suitability of FT-NIR spectroscopy, combined with multivariate data analysis, to be used as a quality control tool in the beer fermentation process. FT-NIR spectroscopy, when combined with LWR, demonstrates to be a perfectly suitable quantitative method to be implemented in the production of beer. Copyright © 2014 Elsevier Ltd. All rights reserved.

Visible and infrared reflectance imaging spectroscopy of paintings: pigment mapping and improved infrared reflectography

NASA Astrophysics Data System (ADS)

Delaney, John K.; Zeibel, Jason G.; Thoury, Mathieu; Littleton, Roy; Morales, Kathryn M.; Palmer, Michael; de la Rie, E. René

2009-07-01

Reflectance imaging spectroscopy, the collection of images in narrow spectral bands, has been developed for remote sensing of the Earth. In this paper we present findings on the use of imaging spectroscopy to identify and map artist pigments as well as to improve the visualization of preparatory sketches. Two novel hyperspectral cameras, one operating from the visible to near-infrared (VNIR) and the other in the shortwave infrared (SWIR), have been used to collect diffuse reflectance spectral image cubes on a variety of paintings. The resulting image cubes (VNIR 417 to 973 nm, 240 bands, and SWIR 970 to 1650 nm, 85 bands) were calibrated to reflectance and the resulting spectra compared with results from a fiber optics reflectance spectrometer (350 to 2500 nm). The results show good agreement between the spectra acquired with the hyperspectral cameras and those from the fiber reflectance spectrometer. For example, the primary blue pigments and their distribution in Picasso's Harlequin Musician (1924) are identified from the reflectance spectra and agree with results from X-ray fluorescence data and dispersed sample analysis. False color infrared reflectograms, obtained from the SWIR hyperspectral images, of extensively reworked paintings such as Picasso's The Tragedy (1903) are found to give improved visualization of changes made by the artist. These results show that including the NIR and SWIR spectral regions along with the visible provides for a more robust identification and mapping of artist pigments than using visible imaging spectroscopy alone.

Host sensitized near-infrared emission in Nd3+ doped different alkaline-sodium-phosphate phosphors

NASA Astrophysics Data System (ADS)

Balakrishna, A.; Swart, H. C.; Kroon, R. E.; Ntwaeaborwa, O. M.

2018-04-01

Near-infrared (NIR) emitting phosphors of different alkaline based sodium-phosphate (MNa[PO4], where M = Mg, Ca, Sr and Ba were prepared by a conventional solution combustion method with fixed doping concentration of Nd3+ (1.0 mol%). The phosphors were characterized by powder X-ray diffraction, field emission scanning electron microscope, Fourier transform infrared spectroscopy, UV-vis spectroscopy and fluorescent spectrophotometry. The optical properties including reflectance, excitation and emission were investigated. The excitation spectra of the phosphors were characterized by a broadband extending from 450 to 900 nm. Upon excitation with a wavelength of 580 nm, the phosphor emits intensely infrared region at 872 nm, 1060 nm and 1325 nm which correspond to the 4F3/2 → 4I9/2, 4F3/2 → 4I11/2 and 4F3/2 → 4I13/2 transitions of Nd3+ ions and were found to vary for the different hosts. The strongest emission wavelength reaches 1060 nm. The most intense emission of Nd3+ was observed from Ca2+ incorporated host. The down conversion emissions of the material fall in the NIR region suggesting that the prepared phosphors have potential application in the development of photonic devices emitting in the NIR.

Test-retest assessment of functional near-infrared spectroscopy to measure risk decision making in young adults

NASA Astrophysics Data System (ADS)

Li, Lin; Lin, Zijing; Cazzell, Mary; Liu, Hanli

2013-03-01

Investigation of the reliability and reproducibility of the hemodynamic response is important for interpretation and understanding of the results of functional near-infrared spectroscopy (fNIRS). It measures optical signals absorbed by the brain tissue and reflects the neuronal activities indirectly. Here we described an fNIRS study measured in the prefrontal region (Brodman area 9, 10, part of 46)to examine the risk decision-making behavior in nine young adults. The Balloon Analog Risk Task (BART) is widely used to test the level of risk taking ability in the field of psychology. BART was a protocol utilized in this study to evoke a risk-taking environment with a gambling-like balloon game in each subject. Specifically, we recorded the brain oxygenated-hemoglobin (HbO) and deoxygenated-hemoglobin (HHb) changes during the two repeated measurements within a time interval of 3 weeks. The results demonstrate that the changes in HbO2 amplitudes have high reliability at the group level, and that the spatial patterns of the tomographic images have high reproducibility in size and a moderate degree of overlap. Overall, this study confirms that the hemodynamic response to risk decision-making (i.e., BART) seen by fNIRS is highly reliable and reproducible.

Probing the Behaviors of Gold Nanorods in Metastatic Breast Cancer Cells Based on UV-vis-NIR Absorption Spectroscopy

PubMed Central

Zhang, Weiqi; Ji, Yinglu; Meng, Jie; Wu, Xiaochun; Xu, Haiyan

2012-01-01

In this work, behaviors of positively-charged AuNRs in a highly metastatic tumor cell line MDA-MB-231 are examined based on UV-vis-NIR absorption spectroscopy in combination with inductively coupled plasma mass spectrometry (ICP-MS), transmission electron microscopy (TEM) and dark-field microscopic observation. It is found that characteristic surface plasmon resonance (SPR) peaks of AuNRs can be detected using spectroscopic method within living cells that have taken up AuNRs. The peak area of transverse SPR band is shown to be proportionally related to the amount of AuNRs in the cells determined with ICP-MS, which suggests a facile and real time quantification method for AuNRs in living cells. The shape of longitudinal SPR band in UV-vis-NIR spectrum reflects the aggregation state of AuNRs in the cells during the incubation period, which is proved by TEM and microscopic observations. Experimental results reveal that AuNRs are internalized by the cells rapidly; the accumulation, distribution and aggregation of AuNRs in the cells compartments are time and dose dependent. The established spectroscopic analysis method can not only monitor the behaviors of AuNRs in living cells but may also be helpful in choosing the optimum laser stimulation wavelength for anti-tumor thermotherapy. PMID:22384113

Hemodynamic and electrophysiological signals of conflict processing in the Chinese-character Stroop task: a simultaneous near-infrared spectroscopy and event-related potential study

NASA Astrophysics Data System (ADS)

Zhai, Jiahuan; Li, Ting; Zhang, Zhongxing; Gong, Hui

2009-09-01

A dual-modality method combining continuous-wave near-infrared spectroscopy (NIRS) and event-related potentials (ERPs) was developed for the Chinese-character color-word Stroop task, which included congruent, incongruent, and neutral stimuli. Sixteen native Chinese speakers participated in this study. Hemodynamic and electrophysiological signals in the prefrontal cortex (PFC) were monitored simultaneously by NIRS and ERP. The hemodynamic signals were represented by relative changes in oxy-, deoxy-, and total hemoglobin concentration, whereas the electrophysiological signals were characterized by the parameters P450, N500, and P600. Both types of signals measured at four regions of the PFC were analyzed and compared spatially and temporally among the three different stimuli. We found that P600 signals correlated significantly with the hemodynamic parameters, suggesting that the PFC executes conflict-solving function. Additionally, we observed that the change in deoxy-Hb concentration showed higher sensitivity in response to the Stroop task than other hemodynamic signals. Correlation between NIRS and ERP signals revealed that the vascular response reflects the cumulative effect of neural activities. Taken together, our findings demonstrate that this new dual-modality method is a useful approach to obtaining more information during cognitive and physiological studies.

Regional Cerebral Abnormalities Measured by Frequency-Domain Near-Infrared Spectroscopy in Pediatric Patients During Extracorporeal Membrane Oxygenation.

PubMed

Tian, Fenghua; Jenks, Christopher; Potter, Donald; Miles, Darryl; Raman, Lakshmi

Extracorporeal membrane oxygenation (ECMO) is a form of advanced cardiorespiratory support provided to critically ill patients with severe respiratory or cardiovascular failure. While children undergoing ECMO therapy have significant risk for neurological morbidity, currently there is a lack of reliable bedside tool to detect the neurologic events for patients on ECMO. This study assessed the feasibility of frequency-domain near-infrared spectroscopy (NIRS) for detection of intracranial complications during ECMO therapy. The frequency-domain NIRS device measured the absorption coefficient (µa) and reduced scattering coefficient (µs') at six cranial positions from seven pediatric patients (0-16 years) during ECMO support and five healthy controls (2-14 years). Regional abnormalities in both absorption and scattering were identified among ECMO patients. A main finding in this study is that the abnormalities in scattering appear to be associated with lower-than-normal µs' values in regional areas of the brain. Because light scattering originates from the intracellular structures (such as nuclei and mitochondria), a reduction in scattering primarily reflects loss or decreased density of the brain matter. The results from this study indicate a potential to use the frequency-domain NIRS as a safe and complementary technology for detection of intracranial complications during ECMO therapy.

The Validity of Functional Near-Infrared Spectroscopy Recordings of Visuospatial Working Memory Processes in Humans.

PubMed

Witmer, Joëlle S; Aeschlimann, Eva A; Metz, Andreas J; Troche, Stefan J; Rammsayer, Thomas H

2018-04-05

Functional near infrared spectroscopy (fNIRS) is increasingly used for investigating cognitive processes. To provide converging evidence for the validity of fNIRS recordings in cognitive neuroscience, we investigated functional activation in the frontal cortex in 43 participants during the processing of a visuospatial working memory (WM) task and a sensory duration discrimination (DD) task functionally unrelated to WM. To distinguish WM-related processes from a general effect of increased task demand, we applied an adaptive approach, which ensured that subjective task demand was virtually identical for all individuals and across both tasks. Our specified region of interest covered Brodmann Area 8 of the left hemisphere, known for its important role in the execution of WM processes. Functional activation, as indicated by an increase of oxygenated and a decrease of deoxygenated hemoglobin, was shown for the WM task, but not in the DD task. The overall pattern of results indicated that hemodynamic responses recorded by fNIRS are sensitive to specific visuospatial WM capacity-related processes and do not reflect a general effect of increased task demand. In addition, the finding that no such functional activation could be shown for participants with far above-average mental ability suggested different cognitive processes adopted by this latter group.

The Validity of Functional Near-Infrared Spectroscopy Recordings of Visuospatial Working Memory Processes in Humans

PubMed Central

Witmer, Joëlle S.; Aeschlimann, Eva A.; Metz, Andreas J.; Rammsayer, Thomas H.

2018-01-01

Functional near infrared spectroscopy (fNIRS) is increasingly used for investigating cognitive processes. To provide converging evidence for the validity of fNIRS recordings in cognitive neuroscience, we investigated functional activation in the frontal cortex in 43 participants during the processing of a visuospatial working memory (WM) task and a sensory duration discrimination (DD) task functionally unrelated to WM. To distinguish WM-related processes from a general effect of increased task demand, we applied an adaptive approach, which ensured that subjective task demand was virtually identical for all individuals and across both tasks. Our specified region of interest covered Brodmann Area 8 of the left hemisphere, known for its important role in the execution of WM processes. Functional activation, as indicated by an increase of oxygenated and a decrease of deoxygenated hemoglobin, was shown for the WM task, but not in the DD task. The overall pattern of results indicated that hemodynamic responses recorded by fNIRS are sensitive to specific visuospatial WM capacity-related processes and do not reflect a general effect of increased task demand. In addition, the finding that no such functional activation could be shown for participants with far above-average mental ability suggested different cognitive processes adopted by this latter group. PMID:29621179

Hemodynamic and electrophysiological signals of conflict processing in the Chinese-character Stroop task: a simultaneous near-infrared spectroscopy and event-related potential study.

PubMed

Zhai, Jiahuan; Li, Ting; Zhang, Zhongxing; Gong, Hui

2009-01-01

A dual-modality method combining continuous-wave near-infrared spectroscopy (NIRS) and event-related potentials (ERPs) was developed for the Chinese-character color-word Stroop task, which included congruent, incongruent, and neutral stimuli. Sixteen native Chinese speakers participated in this study. Hemodynamic and electrophysiological signals in the prefrontal cortex (PFC) were monitored simultaneously by NIRS and ERP. The hemodynamic signals were represented by relative changes in oxy-, deoxy-, and total hemoglobin concentration, whereas the electrophysiological signals were characterized by the parameters P450, N500, and P600. Both types of signals measured at four regions of the PFC were analyzed and compared spatially and temporally among the three different stimuli. We found that P600 signals correlated significantly with the hemodynamic parameters, suggesting that the PFC executes conflict-solving function. Additionally, we observed that the change in deoxy-Hb concentration showed higher sensitivity in response to the Stroop task than other hemodynamic signals. Correlation between NIRS and ERP signals revealed that the vascular response reflects the cumulative effect of neural activities. Taken together, our findings demonstrate that this new dual-modality method is a useful approach to obtaining more information during cognitive and physiological studies.

Quantitative estimation of soil salinity by means of different modeling methods and visible-near infrared (VIS–NIR) spectroscopy, Ebinur Lake Wetland, Northwest China

PubMed Central

Wang, Jingzhe; Abulimiti, Aerzuna; Cai, Lianghong

2018-01-01

Soil salinization is one of the most common forms of land degradation. The detection and assessment of soil salinity is critical for the prevention of environmental deterioration especially in arid and semi-arid areas. This study introduced the fractional derivative in the pretreatment of visible and near infrared (VIS–NIR) spectroscopy. The soil samples (n = 400) collected from the Ebinur Lake Wetland, Xinjiang Uyghur Autonomous Region (XUAR), China, were used as the dataset. After measuring the spectral reflectance and salinity in the laboratory, the raw spectral reflectance was preprocessed by means of the absorbance and the fractional derivative order in the range of 0.0–2.0 order with an interval of 0.1. Two different modeling methods, namely, partial least squares regression (PLSR) and random forest (RF) with preprocessed reflectance were used for quantifying soil salinity. The results showed that more spectral characteristics were refined for the spectrum reflectance treated via fractional derivative. The validation accuracies showed that RF models performed better than those of PLSR. The most effective model was established based on RF with the 1.5 order derivative of absorbance with the optimal values of R2 (0.93), RMSE (4.57 dS m−1), and RPD (2.78 ≥ 2.50). The developed RF model was stable and accurate in the application of spectral reflectance for determining the soil salinity of the Ebinur Lake wetland. The pretreatment of fractional derivative could be useful for monitoring multiple soil parameters with higher accuracy, which could effectively help to analyze the soil salinity. PMID:29736341

Quantitative estimation of soil salinity by means of different modeling methods and visible-near infrared (VIS-NIR) spectroscopy, Ebinur Lake Wetland, Northwest China.

PubMed

Wang, Jingzhe; Ding, Jianli; Abulimiti, Aerzuna; Cai, Lianghong

2018-01-01

Soil salinization is one of the most common forms of land degradation. The detection and assessment of soil salinity is critical for the prevention of environmental deterioration especially in arid and semi-arid areas. This study introduced the fractional derivative in the pretreatment of visible and near infrared (VIS-NIR) spectroscopy. The soil samples ( n  = 400) collected from the Ebinur Lake Wetland, Xinjiang Uyghur Autonomous Region (XUAR), China, were used as the dataset. After measuring the spectral reflectance and salinity in the laboratory, the raw spectral reflectance was preprocessed by means of the absorbance and the fractional derivative order in the range of 0.0-2.0 order with an interval of 0.1. Two different modeling methods, namely, partial least squares regression (PLSR) and random forest (RF) with preprocessed reflectance were used for quantifying soil salinity. The results showed that more spectral characteristics were refined for the spectrum reflectance treated via fractional derivative. The validation accuracies showed that RF models performed better than those of PLSR. The most effective model was established based on RF with the 1.5 order derivative of absorbance with the optimal values of R 2 (0.93), RMSE (4.57 dS m -1 ), and RPD (2.78 ≥ 2.50). The developed RF model was stable and accurate in the application of spectral reflectance for determining the soil salinity of the Ebinur Lake wetland. The pretreatment of fractional derivative could be useful for monitoring multiple soil parameters with higher accuracy, which could effectively help to analyze the soil salinity.

Noninvasive detection of intracerebral hemorrhage using near-infrared spectroscopy (NIRS)

NASA Astrophysics Data System (ADS)

Hennes, Hans-Juergen; Lott, Carsten; Windirsch, Michael; Hanley, Daniel F.; Boor, Stephan; Brambrink, Ansgar; Dick, Wolfgang

1998-01-01

Intracerebral Hemorrhage (IH) is an important cause of secondary brain injury in neurosurgical patients. Early identification and treatment improve neurologic outcome. We have tested Near Infrared Spectroscopy (NIRS) as an alternative noninvasive diagnostic tool compared to CT-Scans to detect IH. We prospectively studied 212 patients with neurologic symptoms associated with intracranial pathology before performing a CT-scan. NIRS signals indicated pathologies in 181 cases (sensitivity 0.96; specificity 0.29). In a subgroup of subdural hematomas NIRS detected 45 of 46 hematomas (sensitivity 0.96; specificity 0.79). Identification of intracerebral hemorrhage using NIRS has the potential to allow early treatment, thus possibly avoiding further injury.

Noninvasive detection of intracerebral hemorrhage using near-infrared spectroscopy (NIRS)

NASA Astrophysics Data System (ADS)

Hennes, Hans J.; Lott, C.; Windirsch, Michael; Hanley, Daniel F.; Boor, Stephan; Brambrink, Ansgar; Dick, Wolfgang

1997-12-01

Intracerebral Hemorrhage (IH) is an important cause of secondary brain injury in neurosurgical patients. Early identification and treatment improve neurologic outcome. We have tested Near Infrared Spectroscopy (NIRS) as an alternative noninvasive diagnostic tool compared to CT-Scans to detect IH. We prospectively studied 212 patients with neurologic symptoms associated with intracranial pathology before performing a CT-scan. NIRS signals indicated pathologies in 181 cases (sensitivity 0.96; specificity 0.29). In a subgroup of subdural hematomas NIRS detected 45 of 46 hematomas (sensitivity 0.96; specificity 0.79). Identification of intracerebral hemorrhage using NIRS has the potential to allow early treatment, thus possibly avoiding further injury.

Near-Infrared (NIR) Spectroscopy of Synthetic Hydroxyapatites and Human Dental Tissues.

PubMed

Kolmas, Joanna; Marek, Dariusz; Kolodziejski, Waclaw

2015-08-01

Near-infrared spectroscopy (NIR) was used to analyze synthetic hydroxyapatite calcined at various temperatures, synthetic carbonated hydroxyapatite, and human hard dental tissues (enamel and dentin). The NIR bands of those materials in the combination, first-overtone, and second-overtone spectral regions were assigned and evaluated for structural characterization. They were attributed to adsorbed and structural water, structural hydroxyl (OH) groups and surface P-OH groups. The NIR spectral features were quantitatively discussed in view of proton solid-state magic-angle spinning nuclear magnetic resonance ((1)H MAS NMR) results. We conclude that the NIR spectra of apatites are useful in the structural characterization of synthetic and biogenic apatites.

NirN Protein from Pseudomonas aeruginosa is a Novel Electron-bifurcating Dehydrogenase Catalyzing the Last Step of Heme d1 Biosynthesis*

PubMed Central

Adamczack, Julia; Hoffmann, Martin; Papke, Ulrich; Haufschildt, Kristin; Nicke, Tristan; Bröring, Martin; Sezer, Murat; Weimar, Rebecca; Kuhlmann, Uwe; Hildebrandt, Peter; Layer, Gunhild

2014-01-01

Heme d1 plays an important role in denitrification as the essential cofactor of the cytochrome cd1 nitrite reductase NirS. At present, the biosynthesis of heme d1 is only partially understood. The last step of heme d1 biosynthesis requires a so far unknown enzyme that catalyzes the introduction of a double bond into one of the propionate side chains of the tetrapyrrole yielding the corresponding acrylate side chain. In this study, we show that a Pseudomonas aeruginosa PAO1 strain lacking the NirN protein does not produce heme d1. Instead, the NirS purified from this strain contains the heme d1 precursor dihydro-heme d1 lacking the acrylic double bond, as indicated by UV-visible absorption spectroscopy and resonance Raman spectroscopy. Furthermore, the dihydro-heme d1 was extracted from purified NirS and characterized by UV-visible absorption spectroscopy and finally identified by high-resolution electrospray ionization mass spectrometry. Moreover, we show that purified NirN from P. aeruginosa binds the dihydro-heme d1 and catalyzes the introduction of the acrylic double bond in vitro. Strikingly, NirN uses an electron bifurcation mechanism for the two-electron oxidation reaction, during which one electron ends up on its heme c cofactor and the second electron reduces the substrate/product from the ferric to the ferrous state. On the basis of our results, we propose novel roles for the proteins NirN and NirF during the biosynthesis of heme d1. PMID:25204657

XRF and UV-Vis-NIR analyses of medieval wall paintings of al-Qarawiyyin Mosque (Morocco)

NASA Astrophysics Data System (ADS)

Fikri, I.; El Amraoui, M.; Haddad, M.; Ettahiri, A. S.; Bellot-Gurlet, L.; Falguères, C.; Lebon, M.; Nespoulet, R.; Ait Lyazidi, S.; Bejjit, L.

2018-05-01

Medieval wall painting fragments, taken at the medieval Mosque of al-Qarawiyyin in Fez, have been investigated by means of X-ray fluorescence and UV-Vis-NIR diffuse reflectance spectroscopies. The analyses permitted to determine the palette of pigments used by craftsmen of the time. Hematite or red ochre were used to obtain red brown colours, calcite for white, copper-based pigments for blue and blue-grey shades while a mixture of cinnabar, lead-based pigments and hematite was adopted to make red-orange colours. Furthermore, the analysis of mortars (external layer and plaster) on these wall painting samples revealed that they are composed mainly by calcite and sometimes by additional compounds such as quartz and gypsum.

High resolution scanning of radial strips cut from increment cores by near infrared spectroscopy

Treesearch

P. David Jones; Laurence R. Schimleck; Chi-Leung So; Alexander III Clark; Richard F. Daniels

2007-01-01

Near infrared (NIR) spectroscopy provides a rapid method for the determination of wood properties of radial strips. The spatial resolution of the NIR measurements has generally been limited to sections 10 mm wide and as a consequence the estimation of wood properties of individual rings or within rings has not been possible. Many different NIR instruments can be used...

Handling of uncertainty due to interference fringe in FT-NIR transmittance spectroscopy - Performance comparison of interference elimination techniques using glucose-water system

NASA Astrophysics Data System (ADS)

Beganović, Anel; Beć, Krzysztof B.; Henn, Raphael; Huck, Christian W.

2018-05-01

The applicability of two elimination techniques for interferences occurring in measurements with cells of short pathlength using Fourier transform near-infrared (FT-NIR) spectroscopy was evaluated. Due to the growing interest in the field of vibrational spectroscopy in aqueous biological fluids (e.g. glucose in blood), aqueous solutions of D-(+)-glucose were prepared and split into a calibration set and an independent validation set. All samples were measured with two FT-NIR spectrometers at various spectral resolutions. Moving average smoothing (MAS) and fast Fourier transform filter (FFT filter) were applied to the interference affected FT-NIR spectra in order to eliminate the interference pattern. After data pre-treatment, partial least squares regression (PLSR) models using different NIR regions were constructed using untreated (interference affected) spectra and spectra treated with MAS and FFT filter. The prediction of the independent validation set revealed information about the performance of the utilized interference elimination techniques, as well as the different NIR regions. The results showed that the combination band of water at approx. 5200 cm-1 is of great importance since its performance was superior to the one of the so-called first overtone of water at approx. 6800 cm-1. Furthermore, this work demonstrated that MAS and FFT filter are fast and easy-to-use techniques for the elimination of interference fringes in FT-NIR transmittance spectroscopy.

A fecal near-infrared reflectance spectroscopy-aided methodology to determine goat dietary composition in a Mediterranean shrubland.

PubMed

Glasser, T; Landau, S; Ungar, E D; Perevolotsky, A; Dvash, L; Muklada, H; Kababya, D; Walker, J W

2008-06-01

An ecologically sound approach to the problem of brush encroachment onto Israeli rangeland might be their utilization by goats, but better knowledge of the feeding selectivity and ability of goats to thrive in encroached areas is required to devise viable production systems. Direct observation of bites could provide precise and accurate estimates of diet selection, but construction of a sufficiently large database would require too much time. The present study describes the first attempt to construct fecal near-infrared reflectance spectroscopy (NIRS) calibrations of the botanical and nutritional composition of the diet, and of the total intake of free-ranging goats, based on reference values determined with bite-count procedures. Calibration of fecal NIRS was based on 43 observations encompassing 3 goat breeds and 4 periods (spring, summer, and fall of 2004, and spring of 2005). Each observation comprised 242 min of continuous recording of the species and bite-type category selected by a single animal, on each of 2 consecutive days. The mass and chemical quality of each species and bite-type category-a total of more than 200,000 bites-were determined by using the simulated bite technique. Associated feces were scanned in the 1,100- to 2,500-nm range with a reflectance monochromator. Fecal NIRS calibrations had reasonable precision for dietary percentages of the 3 main botanical components: herbaceous vegetation (as one category; R(2) = 0.85), Phillyrea latifolia (R(2) = 0.89), and tannin-rich Pistacia lentiscus (R(2) = 0.77), with SE of cross-validation (SECV) of 7.8, 6.3, and 5.6% of DM, respectively. The R(2) values for dietary percentages of CP, NDF, IVDMD, and polyethylene glycol-binding tannins were 0.93, 0.88, 0.91, and 0.74, respectively, with SECV values of 0.9, 2.1, 4.3, and 0.9% of DM, respectively. The R(2) values for intakes of herbaceous vegetation, P. latifolia, and P. lentiscus were 0.80, 0.75, and 0.65, with SECV values of 71, 64, and 46 g of DM/d, respectively. The R(2) values for the daily nutrient intakes were below 0.60. Fecal NIRS data can be used to expand the databases of botanical and nutritional dietary composition when observed and resident animals graze simultaneously, but intakes should be calculated from fecal NIRS-predicted dietary DM composition and an independent evaluation of DMI.

Cropland Field Monitoring: MMV Page 1 Montana Cropland Enrolled Farm Fields Carbon Sequestration Field Sampling, Measurement, Monitoring, and Verification: Application of Visible-Near Infrared Diffuse Reflectance Spectroscopy (VNIR) and Laser-induced Breakdown Spectroscopy (LIBS)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee Spangler; Ross Bricklemyer; David Brown

2012-03-15

There is growing need for rapid, accurate, and inexpensive methods to measure, and verify soil organic carbon (SOC) change for national greenhouse gas accounting and the development of a soil carbon trading market. Laboratory based soil characterization typically requires significant soil processing, which is time and resource intensive. This severely limits application for large-region soil characterization. Thus, development of rapid and accurate methods for characterizing soils are needed to map soil properties for precision agriculture applications, improve regional and global soil carbon (C) stock and flux estimates and efficiently map sub-surface metal contamination, among others. The greatest gains for efficientmore » soil characterization will come from collecting soil data in situ, thus minimizing soil sample transportation, processing, and lab-based measurement costs. Visible and near-infrared diffuse reflectance spectroscopy (VisNIR) and laser-induced breakdown spectroscopy (LIBS) are two complementary, yet fundamentally different spectroscopic techniques that have the potential to meet this need. These sensors have the potential to be mounted on a soil penetrometer and deployed for rapid soil profile characterization at field and landscape scales. Details of sensor interaction, efficient data management, and appropriate statistical analysis techniques for model calibrations are first needed. In situ or on-the-go VisNIR spectroscopy has been proposed as a rapid and inexpensive tool for intensively mapping soil texture and organic carbon (SOC). While lab-based VisNIR has been established as a viable technique for estimating various soil properties, few experiments have compared the predictive accuracy of on-the-go and lab-based VisNIR. Eight north central Montana wheat fields were intensively interrogated using on-the-go and lab-based VisNIR. Lab-based spectral data consistently provided more accurate predictions than on-the-go data. However, neither in situ nor lab-based spectroscopy yielded even semi-quantitative SOC predictions. There was little SOC variability to explain across the eight fields, and on-the-go VisNIR was not able to capture the subtle SOC variability in these Montana soils. With more variation in soil clay content compared to SOC, both lab and on-the-go VisNIR showed better explanatory power. There are several potential explanations for poor on-the-go predictive accuracy: soil heterogeneity, field moisture, consistent sample presentation, and a difference between the spatial support of on-the-go measurements and soil samples collected for laboratory analyses. Though the current configuration of a commercially available on-the-go VisNIR system allows for rapid field scanning, on-the-go soil processing (i.e. drying, crushing, and sieving) could improve soil carbon predictions. Laser-induced breakdown spectroscopy (LIBS) is an emerging elemental analysis technology with the potential to provide rapid, accurate and precise analysis of soil constituents, such as carbon, in situ across landscapes. The research team evaluated the accuracy of LIBS for measuring soil profile carbon in field-moist, intact soil cores simulating conditions that might be encountered by a probe-mounted LIBS instrument measuring soil profile carbon in situ. Over the course of three experiments, more than120 intact soil cores from eight north central Montana wheat fields and the Washington State University (WSU) Cook Agronomy Farm near Pullman, WA were interrogated with LIBS for rapid total carbon (TC), inorganic carbon (IC), and SOC determination. Partial least squares regression models were derived and independently validated at field- and regional scales. Researchers obtained the best LIBS validation predictions for IC followed by TC and SOC. Laser-induced breakdown spectroscopy is fundamentally an elemental analysis technique, yet LIBS PLS2 models appeared to discriminate IC from TC. Regression coefficients from initial models suggested a reliance upon stoichiometric relationships between carbon (247.8 nm) and other elements related to total and inorganic carbon in the soil matrix [Ca (210.2 nm, 211.3 nm, and 220.9 nm), Mg (279.55-280.4 nm, 285.26 nm), and Si (251.6 nm, 288.1 nm)]. Expanding the LIBS spectral range to capture emissions from a broader range of elements related to soil organic matter was explored using two spectrometer systems to improve SOC predictions. Results for increasing the spectral range of LIBS to the full 200-800 nm found modest gains in prediction accuracy for IC, but no gains for predicting TC or SOC. Poor SOC predictions are likely a function of (1) the lack of a consistent/definable molecular composition of SOC, (2) relatively little variation in SOC across field sites, and (3) inorganic carbon constituting the primary form of soil carbon, particularly for Montana soils.« less

Simultaneous determination of the impurity and radial tensile strength of reduced glutathione tablets by a high selective NIR-PLS method.

PubMed

Li, Juan; Jiang, Yue; Fan, Qi; Chen, Yang; Wu, Ruanqi

2014-05-05

This paper establishes a high-throughput and high selective method to determine the impurity named oxidized glutathione (GSSG) and radial tensile strength (RTS) of reduced glutathione (GSH) tablets based on near infrared (NIR) spectroscopy and partial least squares (PLS). In order to build and evaluate the calibration models, the NIR diffuse reflectance spectra (DRS) and transmittance spectra (TS) for 330 GSH tablets were accurately measured by using the optimized parameter values. For analyzing GSSG or RTS of GSH tablets, the NIR-DRS or NIR-TS were selected, subdivided reasonably into calibration and prediction sets, and processed appropriately with chemometric techniques. After selecting spectral sub-ranges and neglecting spectrum outliers, the PLS calibration models were built and the factor numbers were optimized. Then, the PLS models were evaluated by the root mean square errors of calibration (RMSEC), cross-validation (RMSECV) and prediction (RMSEP), and by the correlation coefficients of calibration (R(c)) and prediction (R(p)). The results indicate that the proposed models have good performances. It is thus clear that the NIR-PLS can simultaneously, selectively, nondestructively and rapidly analyze the GSSG and RTS of GSH tablets, although the contents of GSSG impurity were quite low while those of GSH active pharmaceutical ingredient (API) quite high. This strategy can be an important complement to the common NIR methods used in the on-line analysis of API in pharmaceutical preparations. And this work expands the NIR applications in the high-throughput and extraordinarily selective analysis. Copyright © 2014 Elsevier B.V. All rights reserved.

Quantitative analysis of multi-component gas mixture based on AOTF-NIR spectroscopy

NASA Astrophysics Data System (ADS)

Hao, Huimin; Zhang, Yong; Liu, Junhua

2007-12-01

Near Infrared (NIR) spectroscopy analysis technology has attracted many eyes and has wide application in many domains in recent years because of its remarkable advantages. But the NIR spectrometer can only be used for liquid and solid analysis by now. In this paper, a new quantitative analysis method of gas mixture by using new generation NIR spectrometer is explored. To collect the NIR spectra of gas mixtures, a vacuumable gas cell was designed and assembled to Luminar 5030-731 Acousto-Optic Tunable Filter (AOTF)-NIR spectrometer. Standard gas samples of methane (CH 4), ethane (C IIH 6) and propane (C 3H 8) are diluted with super pure nitrogen via precision volumetric gas flow controllers to obtain gas mixture samples of different concentrations dynamically. The gas mixtures were injected into the gas cell and the spectra of wavelength between 1100nm-2300nm were collected. The feature components extracted from gas mixture spectra by using Partial Least Squares (PLS) were used as the inputs of the Support Vector Regress Machine (SVR) to establish the quantitative analysis model. The effectiveness of the model is tested by the samples of predicting set. The prediction Root Mean Square Error (RMSE) of CH 4, C IIH 6 and C 3H 8 is respectively 1.27%, 0.89%, and 1.20% when the concentrations of component gas are over 0.5%. It shows that the AOTF-NIR spectrometer with gas cell can be used for gas mixture analysis. PLS combining with SVR has a good performance in NIR spectroscopy analysis. This paper provides the bases for extending the application of NIR spectroscopy analysis to gas detection.

[Rapid assessment of critical quality attributes of Chinese materia medica (II): strategy of NIR assignment].

PubMed

Pei, Yan-Ling; Wu, Zhi-Sheng; Shi, Xin-Yuan; Zhou, Lu-Wei; Qiao, Yan-Jiang

2014-09-01

The present paper firstly reviewed the research progress and main methods of NIR spectral assignment coupled with our research results. Principal component analysis was focused on characteristic signal extraction to reflect spectral differences. Partial least squares method was concerned with variable selection to discover characteristic absorption band. Two-dimensional correlation spectroscopy was mainly adopted for spectral assignment. Autocorrelation peaks were obtained from spectral changes, which were disturbed by external factors, such as concentration, temperature and pressure. Density functional theory was used to calculate energy from substance structure to establish the relationship between molecular energy and spectra change. Based on the above reviewed method, taking a NIR spectral assignment of chlorogenic acid as example, a reliable spectral assignment for critical quality attributes of Chinese materia medica (CMM) was established using deuterium technology and spectral variable selection. The result demonstrated the assignment consistency according to spectral features of different concentrations of chlorogenic acid and variable selection region of online NIR model in extract process. Although spectral assignment was initial using an active pharmaceutical ingredient, it is meaningful to look forward to the futurity of the complex components in CMM. Therefore, it provided methodology for NIR spectral assignment of critical quality attributes in CMM.

Feasibility of using diffuse reflectance spectroscopy for the quantification of brain edema

NASA Astrophysics Data System (ADS)

Rodriguez, Juan G.; Sisson, Cynthia; Hendricks, Chad; Pattillo, Chris; McWaters, Megan; Hardjasudarma, Mardjohan; Quarles, Chad; Yaroslavsky, Anna N.; Yaroslavsky, Ilya V.; Battarbee, Harold

2001-05-01

Many diseased states of the brain can result in the displacement of brain tissues and restrict cerebral blood flow, disrupting function in a life-threatening manner. Clinical examples where displacements are observed include venous thromboses, hematomas, strokes, tumors, abscesses, and, particularly, brain edema. For the latter, the brain tissue swells, displacing the cerebral spinal fluid (CSF) layer that surrounds it, eventually pressing itself against the skull. Under such conditions, catheters are often inserted into the brain's ventricles or the subarachnoid space to monitor increased pressure. These are invasive procedures that incur increased risk of infection and consequently are used reluctantly by clinicians. Recent studies in the field of biomedical optics have suggested that the presence or absence of the CSF layer can lead to dramatic changes in NIR signals obtained from diffuse reflectance measurements around the head. In this study, we consider how this sensitivity of NIR signals to CSF might be exploited to non-invasively monitor the onset and resolution of brain edema.

Recent advances in the use of non-destructive near infrared spectroscopy on intact olive fruits

USDA-ARS?s Scientific Manuscript database

The objective of this review is to illustrate the state of the art in the use of non-destructive near infrared (NIR) spectroscopy for quality evaluation of intact fruit in the olive industry. First, the most recent studies regarding the application of non-destructive NIR spectroscopy methods to asse...

Application of near-infrared image processing in agricultural engineering

NASA Astrophysics Data System (ADS)

Chen, Ming-hong; Zhang, Guo-ping; Xia, Hongxing

2009-07-01

Recently, with development of computer technology, the application field of near-infrared image processing becomes much wider. In this paper the technical characteristic and development of modern NIR imaging and NIR spectroscopy analysis were introduced. It is concluded application and studying of the NIR imaging processing technique in the agricultural engineering in recent years, base on the application principle and developing characteristic of near-infrared image. The NIR imaging would be very useful in the nondestructive external and internal quality inspecting of agricultural products. It is important to detect stored-grain insects by the application of near-infrared spectroscopy. Computer vision detection base on the NIR imaging would be help to manage food logistics. Application of NIR imaging promoted quality management of agricultural products. In the further application research fields of NIR image in the agricultural engineering, Some advices and prospect were put forward.

A near-infrared reflectance spectroscopic method for the direct analysis of several fodder-related chemical components in drumstick (Moringa oleifera Lam.) leaves.

PubMed

Zhang, Junjie; Li, Shuqi; Lin, Mengfei; Yang, Endian; Chen, Xiaoyang

2018-05-01

The drumstick tree has traditionally been used as foodstuff and fodder in several countries. Due to its high nutritional value and good biomass production, interest in this plant has increased in recent years. It has therefore become important to rapidly and accurately evaluate drumstick quality. In this study, we addressed the optimization of Near-infrared spectroscopy (NIRS) to analyze crude protein, crude fat, crude fiber, iron (Fe), and potassium (K) in a variety of drumstick accessions (N = 111) representing different populations, cultivation programs, and climates. Partial least-squares regression with internal cross-validation was used to evaluate the models and identify possible spectral outliers. The calibration statistics for these fodder-related chemical components suggest that NIRS can predict these parameters in a wide range of drumstick types with high accuracy. The NIRS calibration models developed in this study will be useful in predicting drumstick forage quality for these five quality parameters.

Fast and simultaneous prediction of animal feed nutritive values using near infrared reflectance spectroscopy

NASA Astrophysics Data System (ADS)

Samadi; Wajizah, S.; Munawar, A. A.

2018-02-01

Feed plays an important factor in animal production. The purpose of this study is to apply NIRS method in determining feed values. NIRS spectra data were acquired for feed samples in wavelength range of 1000 - 2500 nm with 32 scans and 0.2 nm wavelength. Spectral data were corrected by de-trending (DT) and standard normal variate (SNV) methods. Prediction of in vitro dry matter digestibility (IVDMD) and in vitro organic matter digestibility (IVOMD) were established as model by using principal component regression (PCR) and validated using leave one out cross validation (LOOCV). Prediction performance was quantified using coefficient correlation (r) and residual predictive deviation (RPD) index. The results showed that IVDMD and IVOMD can be predicted by using SNV spectra data with r and RPD index: 0.93 and 2.78 for IVDMD ; 0.90 and 2.35 for IVOMD respectively. In conclusion, NIRS technique appears feasible to predict animal feed nutritive values.

Comparison of Pinus taeda L. whole-tree wood property calibrations using diffuse reflectance near infrared spectra obtained using a variety of sampling options

Treesearch

P. David Jones; Laurence R. Schimleck; Richard F. Daniels; Alexander Clark; Robert C. Purnell

2008-01-01

A necessary objective for tree-breeding programs, with a focus on wood quality, is the measurement of wood properties on a whole-tree basis, however, the time and cost involved limits the numbers of trees sampled. Near infrared (NIR) spectroscopy provides an alternative and recently, it has been demonstrated that calibrations based on milled increment cores and whole-...

Optical mechanisms for detection of lipid-rich atherosclerotic plaques by near-infrared spectroscopy

NASA Astrophysics Data System (ADS)

Hull, Edward L.; Gardner, Craig M.; Muller, James E.; Muller, Vianna J.; Salvato, Christopher V.; Lisauskas, Jennifer B.; Caplan, Jay D.

2008-02-01

InfraReDx has developed a spectroscopic cardiac catheter system capable of acquiring near-infrared (NIR) reflectance spectra from coronary arteries in vivo for identification of lipid-rich plaques of interest (LRP). The spectral data are analyzed with a chemometric model, producing a hyperspectral image (a chemogram) used to identify LRP in the interrogated region. In this paper, we describe a FT-IR microscopy system for measurement of the NIR scattering and absorption properties of healthy and diseased regions of human coronary arteries in small volumes (~10 μl). Scattering and absorption coefficients are obtained from sequential 140 um x 140 um regions of interest across the face of 500-micron thick, saline-irrigated fresh coronary artery sections. A customized FTIR microscope, measurement protocol, and inversion algorithm are used for optical property determination, and the system is calibrated using measurements of tissue-simulating phantoms having well-characterized optical properties. Tissue optical properties are co-registered with brightfield transmission images as well as with stained histologic thin sections (H&E, Movat Pentachrome, and Oil Red O) acquired from an immediately-adjacent section. The ultimate goal of these experiments is to establish a mechanistic link between the multivariate model predictions displayed on the InfraReDx chemogram and the light-tissue interactions that govern the measured NIR reflectance spectra.

The estimation of recovery time of calf muscle oxygen saturation during exercise by using functional near infrared spectroscopy

NASA Astrophysics Data System (ADS)

Ansari, M. A.; Shojaeifar, M.; Mohajerani, E.

2014-08-01

Several methods of near infrared spectroscopy such as functional near infrared spectroscopy (fNIRS) and pulse oximetry have been applied for monitoring of tissue oxygenation or arterial oxygen saturation. Some vascular diseases can be diagnosed through measurements of tissue oxygenation. In this study, the temporal variation of oxygenation of calf muscle after exercise is studied by fNIRS. First, the accuracy of a low-cost fNIRS system is studied by measuring the oxygenation of a lipid phantom. Moreover, in-vivo study is performed to evaluate the precision of this system. Then, the variation of muscle oxygenation of four persons during exercise is measured and also the recovery time after walking/running is measured by this fNIRS system.

Cerebral near-infrared spectroscopy to evaluate anti-G straining maneuvers in centrifuge training.

PubMed

Kobayashi, Asao; Kikukawa, Azusa; Kimura, Mikihiko; Inui, Takuo; Miyamoto, Yoshinori

2012-08-01

Over the past decade, near-infrared spectroscopy (NIRS) has emerged as an easily manageable noninvasive method for the continuous monitoring of cerebral cortical oxygenation during +Gz exposure. NIRS is also used to evaluate pilot trainees' ability to adequately perform anti-G straining maneuvers in the course of centrifuge training. This study aimed to determine the general patterns and individual differences in NIRS recordings during +Gz exposure. There were 22 healthy male cadets who participated in the study. The centrifuge training profiles included a gradual onset run (GOR, onset rate of 0.1 Gz x s(-1)) and short-term repeated exposures, with Gz levels from 4 to 7 Gz at an onset rate of 1.0 Gz x s(-1) (rapid onset run, ROR). Cortical tissue hemoglobin saturation (tissue oxygenation index, TOI) and changes in the concentration of oxygenated hemoglobin (O2Hb) were recorded from the right forehead during the period of Gz exposure. Most of the subjects successfully performed an anti-G straining maneuver and maintained or increased the cerebral oxygenation level during Gz exposure. In four subjects, however, oxygenation decline was observed at levels over 4 Gz, even though their anti-G systems were functioning. In contrast to the O2Hb response, TOI, which reflects intracranial oxygenation changes, was decreased during the anti-G straining maneuver at Gz onset or during the countdown to a ROR exposure. Although NIRS is an effective tool for monitoring anti-G straining maneuver performance, it should be carefully evaluated in terms of intracranial oxygenation results.

Mapping cerebrovascular reactivity using concurrent fMRI and near infrared spectroscopy

NASA Astrophysics Data System (ADS)

Tong, Yunjie; Bergethon, Peter R.; Frederick, Blaise d.

2011-02-01

Cerebrovascular reactivity (CVR) reflects the compensatory dilatory capacity of cerebral vasculature to a dilatory stimulus and is an important indicator of brain vascular reserve. fMRI has been proven to be an effective imaging technique to obtain the CVR map when the subjects perform CO2 inhalation or the breath holding task (BH). However, the traditional data analysis inaccurately models the BOLD using a boxcar function with fixed time delay. We propose a novel way to process the fMRI data obtained during a blocked BH by using the simultaneously collected near infrared spectroscopy (NIRS) data as regressor1. In this concurrent NIRS and fMRI study, 6 healthy subjects performed a blocked BH (5 breath holds with 20s durations intermitted by 40s of regular breathing). A NIRS probe of two sources and two detectors separated by 3 cm was placed on the right side of prefrontal area of the subjects. The time course of changes in oxy-hemoglobin (Δ[HbO]) was calculated from NIRS data and shifted in time by various amounts, and resampled to the fMRI acquisition rate. Each shifted time course was used as regressor in FEAT (the analysis tool in FSL). The resulting z-statistic maps were concatenated in time and the maximal value was taken along the time for all the voxels to generate a 3-D CVR map. The new method produces more accurate and thorough CVR maps; moreover, it enables us to produce a comparable baseline cerebral vascular map if applied to resting state (RS) data.

In-line near-infrared (NIR) and Raman spectroscopy coupled with principal component analysis (PCA) for in situ evaluation of the transesterification reaction.

PubMed

Fontalvo-Gómez, Miriam; Colucci, José A; Velez, Natasha; Romañach, Rodolfo J

2013-10-01

Biodiesel was synthesized from different commercially available oils while in-line Raman and near-infrared (NIR) spectra were obtained simultaneously, and the spectral changes that occurred during the reaction were evaluated with principal component analysis (PCA). Raman and NIR spectra were acquired every 30 s with fiber optic probes inserted into the reaction vessel. The reaction was performed at 60-70 °C using magnetic stirring. The time of reaction was 90 min, and during this time, 180 Raman and NIR spectra were collected. NIR spectra were collected using a transflectance probe and an optical path length of 1 mm at 8 cm(-1) spectral resolution and averaging 32 scans; for Raman spectra a 3 s exposure time and three accumulations were adequate for the analysis. Raman spectroscopy showed the ester conversion as evidenced by the displacement of the C=O band from 1747 to 1744 cm(-1) and the decrease in the intensity of the 1000-1050 cm(-1) band and the 1405 cm(-1) band as methanol was consumed in the reaction. NIR spectra also showed the decrease in methanol concentration with the band in the 4750-5000 cm(-1) region; this signal is present in the spectra of the transesterification reaction but not in the neat oils. The variations in the intensity of the methanol band were a main factor in the in-line monitoring of the transesterification reaction using Raman and NIR spectroscopy. The score plot of the first principal component showed the progress of the reaction. The final product was analyzed using (1)H nuclear magnetic resonance ((1)H NMR) spectroscopy and using mid-infrared spectroscopy, confirming the conversion of the oils to biodiesel.

Near-infrared imaging of demineralization under sealants

NASA Astrophysics Data System (ADS)

Tom, Henry; Simon, Jacob C.; Chan, Kenneth H.; Darling, Cynthia L.; Fried, Daniel

2014-07-01

Previous studies have shown that near-infrared (NIR) reflectance and transillumination imaging can be used to acquire high contrast images of early caries lesions and composite restorative materials. The aim of the study was to determine the optimum NIR wavelengths for imaging demineralized areas under dental sealants. Fifteen natural human premolars and molars with occlusal lesions were used in this in vitro study. Images before and after application of sealants were acquired using NIR reflectance and NIR transillumination at wavelengths of 1300, 1460, and 1500 to 1700 nm. Images were also acquired using polarization sensitive optical coherence tomography (OCT) for comparison. The highest contrast for NIR reflectance was at 1460 nm and 1500 to 1700 nm. These NIR wavelengths are coincident with higher water absorption. The clear Delton sealant investigated was not visible in either copolarization or cross-polarization OCT images. The wavelength region between 1500 and 1700 nm yielded the highest contrast of lesions under sealants for NIR reflectance measurements.

Near-infrared imaging of demineralization under sealants.

PubMed

Tom, Henry; Simon, Jacob C; Chan, Kenneth H; Darling, Cynthia L; Fried, Daniel

2014-01-01

Previous studies have shown that near-infrared (NIR) reflectance and transillumination imaging can be used to acquire high contrast images of early caries lesions and composite restorative materials. The aim of the study was to determine the optimum NIR wavelengths for imaging demineralized areas under dental sealants. Fifteen natural human premolars and molars with occlusal lesions were used in this in vitro study. Images before and after application of sealants were acquired using NIR reflectance and NIR transillumination at wavelengths of 1300, 1460, and 1500 to 1700 nm. Images were also acquired using polarization sensitive optical coherence tomography (OCT) for comparison. The highest contrast for NIR reflectance was at 1460 nm and 1500 to 1700 nm. These NIR wavelengths are coincident with higher water absorption. The clear Delton sealant investigated was not visible in either copolarization or cross-polarization OCT images. The wavelength region between 1500 and 1700 nm yielded the highest contrast of lesions under sealants for NIR reflectance measurements.

Variability comparison of simultaneous brain near-infrared spectroscopy (NIRS) and functional MRI (fMRI) during visual stimulation

PubMed Central

Minati, Ludovico; Visani, Elisa; Dowell, Nick G; Medford, Nick; Critchley, Hugo D

2011-01-01

Brain near-infrared spectroscopy (NIRS) is emerging as a potential alternative to functional MRI (fMRI). To date, no study has explicitly compared the two techniques in terms of measurement variability, a key parameter dictating attainable statistical power. Here, NIRS and fMRI were simultaneously recorded during event-related visual stimulation. Inter-subject coefficients of variation (CVs) for peak response amplitude were considerably larger for NIRS than fMRI, but inter-subject CVs for response latency and intra-subject CVs for response amplitude were overall comparable. Our results may represent an optimistic estimate of the CVs of NIRS measurements, as optode positioning was guided by structural MRI, which is normally unavailable. We conclude that fMRI may be preferable to NIRS for group comparisons, but NIRS is equally powerful when comparing conditions within participants. The discrepancy between inter- and intra-subject CVs is likely related to variability in head anatomy and tissue properties which may be better accounted for by emerging NIRS technology. PMID:21780948

Physical and arsenic adsorption properties of maghemite and magnetite sub-microparticles

NASA Astrophysics Data System (ADS)

Mejia-Santillan, M. E.; Pariona, N.; Bravo-C., J.; Herrera-Trejo, M.; Montejo-Alvaro, F.; Zarate, A.; Perry, D. L.; Mtz-Enriquez, A. I.

2018-04-01

The topotactic transformation from magnetite to maghemite sub-microparticles was demonstrated by a variety of techniques that include X-ray diffraction, Raman spectroscopy, electron microscopy, Mössbauer spectroscopy, magnetic measurements, and vis-NIR diffuse reflectance. The physical, chemical, and morphological properties of the particles were correlated with their adsorptive properties in water with respect to arsenic (V). The adsorptive properties of the iron oxide are increased by changing the crystal phases involved, specifically, the transformation of magnetite to maghemite. Maghemite sub-microparticles are capable of efficiently decreasing the arsenic content in water from 100 ppb to below the World Health Organization (WHO) guideline of 10 ppb.

Thermally induced conformational changes in polyethylene studied by two-dimensional near-infrared infrared hetero-spectral correlation spectroscopy

NASA Astrophysics Data System (ADS)

Watanabe, Shin; Noda, Isao; Ozaki, Yukihiro

2008-07-01

The amount of nonplanar gauche bonds was monitored as a function of increasing temperature in three different polyethylene (PE) samples by means of mid-infrared (MIR) and near-infrared (NIR) spectroscopy. The hetero-spectral two-dimensional (2D) correlation analysis was carried out between the NIR spectral region of 4365-4235 cm -1 and the well-established MIR spectral region of 1375-1265 cm -1, where bands due to nonplanar conformer are detected. This approach allowed us to identify the NIR band at 4265 cm -1, which behaves in a way similar to MIR bands originating from conformational-defect sequences. By combining the result of our current study and that of our previous report obtained on different types of PE, it is suggested that the NIR band originates from conformational-defect sequences in PE. This finding opens up a unique and useful way to study the state of conformational disorder in PE crystal by NIR spectroscopy, monitoring the intensity of the NIR band at 4265 cm -1. The use of NIR spectroscopy allows researchers to directly probe the degree in the formation of conformational-defect sequences in thick, real-world PE samples that cannot be studied by conventional MIR spectroscopy. The 2D correlation spectroscopy analysis among the MIR CH 2 wagging conformational-defect-mode bands on linear low-density PE (LLDPE) and low-density PE (LDPE) revealed the formation of nonplanar conformer represented by the band at 1368 cm -1 proceeds prior to those by other band at 1308 cm -1. This result agrees well with our previous finding on high-density PE (HDPE). We therefore propose with strong confidence that the bands at 1368 and 1308 cm -1 arise from different conformational-defect sequences, even though both of the bands have been proposed to arise from the same conformer of gtg' ( kink) + gtg sequence.

Comprehensive study of solid pharmaceutical tablets in visible, near infrared (NIR), and longwave infrared (LWIR) spectral regions using a rapid simultaneous ultraviolet/visible/NIR (UVN) + LWIR laser-induced breakdown spectroscopy linear arrays detection system and a fast acousto-optic tunable filter NIR spectrometer.

PubMed

Yang, Clayton S C; Jin, Feng; Swaminathan, Siva R; Patel, Sita; Ramer, Evan D; Trivedi, Sudhir B; Brown, Ei E; Hommerich, Uwe; Samuels, Alan C

2017-10-30

This is the first report of a simultaneous ultraviolet/visible/NIR and longwave infrared laser-induced breakdown spectroscopy (UVN + LWIR LIBS) measurement. In our attempt to study the feasibility of combining the newly developed rapid LWIR LIBS linear array detection system to existing rapid analytical techniques for a wide range of chemical analysis applications, two different solid pharmaceutical tablets, Tylenol arthritis pain and Bufferin, were studied using both a recently designed simultaneous UVN + LWIR LIBS detection system and a fast AOTF NIR (1200 to 2200 nm) spectrometer. Every simultaneous UVN + LWIR LIBS emission spectrum in this work was initiated by one single laser pulse-induced micro-plasma in the ambient air atmosphere. Distinct atomic and molecular LIBS emission signatures of the target compounds measured simultaneously in UVN (200 to 1100 nm) and LWIR (5.6 to 10 µm) spectral regions are readily detected and identified without the need to employ complex data processing. In depth profiling studies of these two pharmaceutical tablets without any sample preparation, one can easily monitor the transition of the dominant LWIR emission signatures from coating ingredients gradually to the pharmaceutical ingredients underneath the coating. The observed LWIR LIBS emission signatures provide complementary molecular information to the UVN LIBS signatures, thus adding robustness to identification procedures. LIBS techniques are more surface specific while NIR spectroscopy has the capability to probe more bulk materials with its greater penetration depth. Both UVN + LWIR LIBS and NIR absorption spectroscopy have shown the capabilities of acquiring useful target analyte spectral signatures in comparable short time scales. The addition of a rapid LWIR spectroscopic probe to these widely used optical analytical methods, such as NIR spectroscopy and UVN LIBS, may greatly enhance the capability and accuracy of the combined system for a comprehensive analysis.

Fourier transform mid-infrared (MIR) and near-infrared (NIR) spectroscopy for rapid quality assessment of Chinese medicine preparation Honghua Oil.

PubMed

Wu, Yan-Wen; Sun, Su-Qin; Zhou, Qun; Leung, Hei-Wun

2008-02-13

Honghua Oil (HHO), a traditional Chinese medicine (TCM) oil preparation, is a mixture of several plant essential oils. In this text, the extended ranges of Fourier transform mid-infrared (FT-MIR) and near infrared (FT-NIR) were recorded for 48 commercially available HHOs of different batches from nine manufacturers. The qualitative and quantitative analysis of three marker components, alpha-pinene, methyl salicylate and eugenol, in different HHO products were performed rapidly by the two vibrational spectroscopic methods, i.e. MIR with horizontal attenuated total reflection (HATR) accessory and NIR with direct sampling technique, followed by partial least squares (PLS) regression treatment of the set of spectra obtained. The results indicated that it was successful to identify alpha-pinene, methyl salicylate and eugenol in all of the samples by simple inspection of the MIR-HATR spectra. Both PLS models established with MIR-HATR and NIR spectral data using gas chromatography (GC) peak areas as calibration reference showed a good linear correlation for each of all three target substances in HHO samples. The above spectroscopic techniques may be the promising methods for the rapid quality assessment/quality control (QA/QC) of TCM oil preparations.

Prediction of Ba, Co and Ni for tropical soils using diffuse reflectance spectroscopy and X-ray fluorescence spectroscopy

NASA Astrophysics Data System (ADS)

Arantes Camargo, Livia; Marques Júnior, José; Reynaldo Ferracciú Alleoni, Luís; Tadeu Pereira, Gener; De Bortoli Teixeira, Daniel; Santos Rabelo de Souza Bahia, Angélica

2017-04-01

Environmental impact assessments may be assisted by spatial characterization of potentially toxic elements (PTEs). Diffuse reflectance spectroscopy (DRS) and X-ray fluorescence spectroscopy (XRF) are rapid, non-destructive, low-cost, prediction tools for a simultaneous characterization of different soil attributes. Although low concentrations of PTEs might preclude the observation of spectral features, their contents can be predicted using spectroscopy by exploring the existing relationship between the PTEs and soil attributes with spectral features. This study aimed to evaluate, in three geomorphic surfaces of Oxisols, the capacity for predicting PTEs (Ba, Co, and Ni) and their spatial variability by means of diffuse reflectance spectroscopy (DRS) and X-ray fluorescence spectroscopy (XRF). For that, soil samples were collected from three geomorphic surfaces and analyzed for chemical, physical, and mineralogical properties, and then analyzed in DRS (visible + near infrared - VIS+NIR and medium infrared - MIR) and XRF equipment. PTE prediction models were calibrated using partial least squares regression (PLSR). PTE spatial distribution maps were built using the values calculated by the calibrated models that reached the best accuracy using geostatistics. PTE prediction models were satisfactorily calibrated using MIR DRS for Ba, and Co (residual prediction deviation - RPD > 3.0), Vis DRS for Ni (RPD > 2.0) and FRX for all the studied PTEs (RPD > 1.8). DRS- and XRF-predicted values allowed the characterization and the understanding of spatial variability of the studied PTEs.

The relationship between dorsolateral prefrontal activation and speech performance-based social anxiety using functional near infrared spectroscopy.

PubMed

Glassman, Lisa H; Kuster, Anootnara T; Shaw, Jena A; Forman, Evan M; Izzetoglu, Meltem; Matteucci, Alyssa; Herbert, James D

2017-06-01

Functional near-infrared (fNIR) spectroscopy is a promising new technology that has demonstrated utility in the study of normal human cognition. We utilized fNIR spectroscopy to examine the effect of social anxiety and performance on hemodynamic activity in the dorsolateral prefrontal cortex (DLPFC). Socially phobic participants and non-clinical participants with varying levels of social anxiety completed a public speaking task in front of a small virtual audience while the DLPFC was being monitored by the fNIR device. The relationship between anxiety and both blood volume (BV) and deoxygenated hemoglobin (Hb) varied significantly as a function of speech performance, such that individuals with low social anxiety who performed well showed an increase in DLPFC activation relative to those who did not perform well. This result suggests that effortful thinking and/or efficient top-down inhibitory control may have been required to complete an impromptu speech task with good performance. In contrast, good performers who were highly socially anxious showed lower DLPFC activation relative to good performers who were low in social anxiety, suggesting autopilot thinking or less-effortful thinking. In poor performers, slight increases in DLPFC activation were observed from low to highly anxious individuals, which may reflect a shift from effortless thinking to heightened self-focused attention. Heightened self-focused attention, poor inhibitory control resulting in excessive fear or anxiety, or low motivation may lower performance. These results suggest that there can be different underlying mechanisms in the brain that affect the level of speech performance in individuals with varying degrees of social anxiety. This study highlights the utility of the fNIR device in the assessment of changes in DLPFC in response to exposure to realistic phobic stimuli, and further supports the potential utility of this technology in the study of the neurophysiology of anxiety disorders.

Review of functional near-infrared spectroscopy in neurorehabilitation

PubMed Central

Mihara, Masahito; Miyai, Ichiro

2016-01-01

Abstract. We provide a brief overview of the research and clinical applications of near-infrared spectroscopy (NIRS) in the neurorehabilitation field. NIRS has several potential advantages and shortcomings as a neuroimaging tool and is suitable for research application in the rehabilitation field. As one of the main applications of NIRS, we discuss its application as a monitoring tool, including investigating the neural mechanism of functional recovery after brain damage and investigating the neural mechanisms for controlling bipedal locomotion and postural balance in humans. In addition to being a monitoring tool, advances in signal processing techniques allow us to use NIRS as a therapeutic tool in this field. With a brief summary of recent studies investigating the clinical application of NIRS using motor imagery task, we discuss the possible clinical usage of NIRS in brain–computer interface and neurofeedback. PMID:27429995

Application of NIR spectroscopy in the assessment of diabetic foot disorders

NASA Astrophysics Data System (ADS)

Schleicher, Eckhard; Hampel, Uwe; Freyer, Richard

2001-10-01

Diabetic foot syndrome (DFS) is a common sequel of long-term diabetes mellitus. There is a urgent need of noninvasive, objective and quantitative diagnostic tools to assess tissue viability and perfusion for a successful therapy. NIR spectroscopy seems to be qualified to measure local capillary hemoglobin saturation of the outer extremities in patients with progressive diabetic disorders. We investigate how NIR spectroscopy can be applied to the assessment of diabetic foot problems such as neuropathy and angiopathy. Thereby we use spatially resolved spectroscopy in conjunction with a specially developed continuous-wave laser spectrometer. Comparison of intra- and interindividual measurements is expected to yield quantitative measures of local tissue viability which is a prerequisite for a successful therapy.

An Advanced Undergraduate Chemistry Laboratory Experiment Exploring NIR Spectroscopy and Chemometrics

ERIC Educational Resources Information Center

Wanke, Randall; Stauffer, Jennifer

2007-01-01

An advanced undergraduate chemistry laboratory experiment to study the advantages and hazards of the coupling of NIR spectroscopy and chemometrics is described. The combination is commonly used for analysis and process control of various ingredients used in agriculture, petroleum and food products.

New PLS analysis approach to wine volatile compounds characterization by near infrared spectroscopy (NIR).

PubMed

Genisheva, Z; Quintelas, C; Mesquita, D P; Ferreira, E C; Oliveira, J M; Amaral, A L

2018-04-25

This work aims to explore the potential of near infrared (NIR) spectroscopy to quantify volatile compounds in Vinho Verde wines, commonly determined by gas chromatography. For this purpose, 105 Vinho Verde wine samples were analyzed using Fourier transform near infrared (FT-NIR) transmission spectroscopy in the range of 5435 cm -1 to 6357 cm -1 . Boxplot and principal components analysis (PCA) were performed for clusters identification and outliers removal. A partial least square (PLS) regression was then applied to develop the calibration models, by a new iterative approach. The predictive ability of the models was confirmed by an external validation procedure with an independent sample set. The obtained results could be considered as quite good with coefficients of determination (R 2 ) varying from 0.94 to 0.97. The current methodology, using NIR spectroscopy and chemometrics, can be seen as a promising rapid tool to determine volatile compounds in Vinho Verde wines. Copyright © 2017 Elsevier Ltd. All rights reserved.

Discrimination of various paper types using diffuse reflectance ultraviolet-visible near-infrared (UV-Vis-NIR) spectroscopy: forensic application to questioned documents.

PubMed

Kumar, Raj; Kumar, Vinay; Sharma, Vishal

2015-06-01

Diffuse reflectance ultraviolet-visible-near-infrared (UV-Vis-NIR) spectroscopy is applied as a means of differentiating various types of writing, office, and photocopy papers (collected from stationery shops in India) on the basis of reflectance and absorbance spectra that otherwise seem to be almost alike in different illumination conditions. In order to minimize bias, spectra from both sides of paper were obtained. In addition, three spectra from three different locations (from one side) were recorded covering the upper, middle, and bottom portions of the paper sample, and the mean average reflectivity of both the sides was calculated. A significant difference was observed in mean average reflectivity of Side A and Side B of the paper using Student's pair >t-test. Three different approaches were used for discrimination: (1) qualitative features of the whole set of samples, (2) principal component analysis, and (3) a combination of both approaches. On the basis of the first approach, i.e., qualitative features, 96.49% discriminating power (DP) was observed, which shows highly significant results with the UV-Vis-NIR technique. In the second approach the discriminating power is further enhanced by incorporating the principal component analysis (PCA) statistical method, where this method describes each UV-Vis spectrum in a group through numerical loading values connected to the first few principal components. All components described 100% variance of the samples, but only the first three PCs are good enough to explain the variance (PC1 = 51.64%, PC2 = 47.52%, and PC3 = 0.54%) of the samples; i.e., the first three PCs described 99.70% of the data, whereas in the third approach, the four samples, C, G, K, and N, out of a total 19 samples, which were not differentiated using qualitative features (approach no. 1), were therefore subjected to PCA. The first two PCs described 99.37% of the spectral features. The discrimination was achieved by using a loading plot between PC1 and PC2. It is therefore concluded that maximum discrimination of writing, office, and photocopy paper could be achieved on the basis of the second approach. Hence, the present inexpensive analytical method can be appropriate for application to routine questioned document examination work in forensic laboratories because it provides nondestructive, quantitative, reliable, and repeatable results.

Transmission near-infrared (NIR) and photon time-of-flight (PTOF) spectroscopy in a comparative analysis of pharmaceuticals.

PubMed

Kamran, Faisal; Abildgaard, Otto H A; Sparén, Anders; Svensson, Olof; Johansson, Jonas; Andersson-Engels, Stefan; Andersen, Peter E; Khoptyar, Dmitry

2015-03-01

We present a comprehensive study of the application of photon time-of-flight spectroscopy (PTOFS) in the wavelength range 1050-1350 nm as a spectroscopic technique for the evaluation of the chemical composition and structural properties of pharmaceutical tablets. PTOFS is compared to transmission near-infrared spectroscopy (NIRS). In contrast to transmission NIRS, PTOFS is capable of directly and independently determining the absorption and reduced scattering coefficients of the medium. Chemometric models were built on the evaluated absorption spectra for predicting tablet drug concentration. Results are compared to corresponding predictions built on transmission NIRS measurements. The predictive ability of PTOFS and transmission NIRS is comparable when models are based on uniformly distributed tablet sets. For non-uniform distribution of tablets based on particle sizes, the prediction ability of PTOFS is better than that of transmission NIRS. Analysis of reduced scattering spectra shows that PTOFS is able to characterize tablet microstructure and manufacturing process parameters. In contrast to the chemometric pseudo-variables provided by transmission NIRS, PTOFS provides physically meaningful quantities such as scattering strength and slope of particle size. The ability of PTOFS to quantify the reduced scattering spectra, together with its robustness in predicting drug content, makes it suitable for such evaluations in the pharmaceutical industry.

Non-destructive technique for determining the viability of soybean (Glycine max) seeds using FT-NIR spectroscopy.

PubMed

Kusumaningrum, Dewi; Lee, Hoonsoo; Lohumi, Santosh; Mo, Changyeun; Kim, Moon S; Cho, Byoung-Kwan

2018-03-01

The viability of seeds is important for determining their quality. A high-quality seed is one that has a high capability of germination that is necessary to ensure high productivity. Hence, developing technology for the detection of seed viability is a high priority in agriculture. Fourier transform near-infrared (FT-NIR) spectroscopy is one of the most popular devices among other vibrational spectroscopies. This study aims to use FT-NIR spectroscopy to determine the viability of soybean seeds. Viable and artificial ageing seeds as non-viable soybeans were used in this research. The FT-NIR spectra of soybean seeds were collected and analysed using a partial least-squares discriminant analysis (PLS-DA) to classify viable and non-viable soybean seeds. Moreover, the variable importance in projection (VIP) method for variable selection combined with the PLS-DA was employed. The most effective wavelengths were selected by the VIP method, which selected 146 optimal variables from the full set of 1557 variables. The results demonstrated that the FT-NIR spectral analysis with the PLS-DA method that uses all variables or the selected variables showed good performance based on the high value of prediction accuracy for soybean viability with an accuracy close to 100%. Hence, FT-NIR techniques with a chemometric analysis have the potential for rapidly measuring soybean seed viability. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Determination of the Mineral Composition and Toxic Element Contents of Propolis by Near Infrared Spectroscopy

PubMed Central

González-Martín, M. Inmaculada; Escuredo, Olga; Revilla, Isabel; Vivar-Quintana, Ana M.; Coello, M. Carmen; Palacios Riocerezo, Carlos; Wells Moncada, Guillermo

2015-01-01

The potential of near infrared spectroscopy (NIR) with remote reflectance fiber-optic probes for determining the mineral composition of propolis was evaluated. This technology allows direct measurements without prior sample treatment. Ninety one samples of propolis were collected in Chile (Bio-Bio region) and Spain (Castilla-León and Galicia regions). The minerals measured were aluminum, calcium, iron, potassium, magnesium, phosphorus, and some potentially toxic trace elements such as zinc, chromium, nickel, copper and lead. The modified partial least squares (MPLS) regression method was used to develop the NIR calibration model. The determination coefficient (R2) and root mean square error of prediction (RMSEP) obtained for aluminum (0.79, 53), calcium (0.83, 94), iron (0.69, 134) potassium (0.95, 117), magnesium (0.70, 99), phosphorus (0.94, 24) zinc (0.87, 10) chromium (0.48, 0.6) nickel (0.52, 0.7) copper (0.64, 0.9) and lead (0.70, 2) in ppm. The results demonstrated that the capacity for prediction can be considered good for wide ranges of potassium, phosphorus and zinc concentrations, and acceptable for aluminum, calcium, magnesium, iron and lead. This indicated that the NIR method is comparable to chemical methods. The method is of interest in the rapid prediction of potentially toxic elements in propolis before consumption. PMID:26540058

Monitoring cerebral oxygen saturation during cardiopulmonary bypass using near-infrared spectroscopy: the relationships with body temperature and perfusion rate.

PubMed

Teng, Yichao; Ding, Haishu; Gong, Qingcheng; Jia, Zaishen; Huang, Lan

2006-01-01

During cardiopulmonary bypass (CPB) because of weak arterial pulsation, near-IR spectroscopy (NIRS) is almost the only available method to monitor cerebral oxygenation noninvasively. Our group develops a NIRS oximeter to monitor regional cerebral oxygenation especially its oxygen saturation (rScO2). To achieve optimal coupling between the sensor and human brain, the distances between the light source and the detectors on it are properly chosen. The oximeter is calibrated by blood gas analysis, and the results indicate that its algorithm is little influenced by either background absorption or overlying tissue. We used it to measure the rScO2 of 15 patients during CPB. It is shown that rScO2 is negatively correlated with body temperature and positively with perfusion rate. There are two critical stages during CPB when rScO2 might be relatively low: one is the low-perfusion-rate stage, the other is the early rewarming stage. During cooling, the changes of total hemoglobin concentration (C(tHb)) compared with its original value is also monitored. It is shown that C(tHb) decreases to a small extent, which may mainly reflect cerebral vasoconstriction induced by cooling. All these results indicate that NIRS can be used to monitor cerebral oxygenation to protect cerebral tissue during CPB.

Combined multi-distance frequency domain and diffuse correlation spectroscopy system with simultaneous data acquisition and real-time analysis.

PubMed

Carp, Stefan A; Farzam, Parisa; Redes, Norin; Hueber, Dennis M; Franceschini, Maria Angela

2017-09-01

Frequency domain near infrared spectroscopy (FD-NIRS) and diffuse correlation spectroscopy (DCS) have emerged as synergistic techniques for the non-invasive assessment of tissue health. Combining FD-NIRS oximetry with DCS measures of blood flow, the tissue oxygen metabolic rate can be quantified, a parameter more closely linked to underlying physiology and pathology than either NIRS or DCS estimates alone. Here we describe the first commercially available integrated instrument, called the "MetaOx", designed to enable simultaneous FD-NIRS and DCS measurements at rates of 10 + Hz, and offering real-time data evaluation. We show simultaneously acquired characterization data demonstrating performance equivalent to individual devices and sample in vivo measurements of pulsation resolved blood flow, forearm occlusion hemodynamic changes and muscle oxygen metabolic rate monitoring during stationary bike exercise.

Combined multi-distance frequency domain and diffuse correlation spectroscopy system with simultaneous data acquisition and real-time analysis

PubMed Central

Carp, Stefan A.; Farzam, Parisa; Redes, Norin; Hueber, Dennis M.; Franceschini, Maria Angela

2017-01-01

Frequency domain near infrared spectroscopy (FD-NIRS) and diffuse correlation spectroscopy (DCS) have emerged as synergistic techniques for the non-invasive assessment of tissue health. Combining FD-NIRS oximetry with DCS measures of blood flow, the tissue oxygen metabolic rate can be quantified, a parameter more closely linked to underlying physiology and pathology than either NIRS or DCS estimates alone. Here we describe the first commercially available integrated instrument, called the “MetaOx”, designed to enable simultaneous FD-NIRS and DCS measurements at rates of 10 + Hz, and offering real-time data evaluation. We show simultaneously acquired characterization data demonstrating performance equivalent to individual devices and sample in vivo measurements of pulsation resolved blood flow, forearm occlusion hemodynamic changes and muscle oxygen metabolic rate monitoring during stationary bike exercise. PMID:29026684

[Application progress on near infrared spectroscopy in quality control and process monitoring of traditional Chinese medicine].

PubMed

Li, Wenlong; Qu, Haibin

2017-01-25

The industry of traditional Chinese medicine (TCM) encounters problems like quality fluctuation of raw materials and unstandardized production process. Near infrared (NIR) spectroscopy technology is widely used in quality control of TCM because of its abundant information, fast and nondestructive characters. The main applications include quantitative analysis of Chinese medicinal materials, intermediates and Chinese patent medicines; the authenticity of TCM, species, origins and manufacturers; monitoring and control of the extraction, alcohol precipitation, column chromatography and blending process. This article reviews the progress on the application of NIR spectroscopy technology in TCM field. In view of the problems existing in the application, the article proposes that the standardization of NIR analysis method should be developed according to specific characteristics of TCM, which will promote the application of NIR technology in the TCM industry.

Quantification of the cortical contribution to the NIRS signal over the motor cortex using concurrent NIRS-fMRI measurements

PubMed Central

Gagnon, Louis; Yücel, Meryem A.; Dehaes, Mathieu; Cooper, Robert J.; Perdue, Katherine L.; Selb, Juliette; Huppert, Theodore J.; Hoge, Richard D.; Boas, David A.

2011-01-01

Near-Infrared Spectroscopy (NIRS) measures the functional hemodynamic response occuring at the surface of the cortex. Large pial veins are located above the surface of the cerebral cortex. Following activation, these veins exhibit oxygenation changes but their volume likely stays constant. The back-reflection geometry of the NIRS measurement renders the signal very sensitive to these superficial pial veins. As such, the measured NIRS signal contains contributions from both the cortical region as well as the pial vasculature. In this work, the cortical contribution to the NIRS signal was investigated using (1) Monte Carlo simulations over a realistic geometry constructed from anatomical and vascular MRI and (2) multimodal NIRS-BOLD recordings during motor stimulation. A good agreement was found between the simulations and the modeling analysis of in vivo measurements. Our results suggest that the cortical contribution to the deoxyhemoglobin signal change (ΔHbR) is equal to 16–22% of the cortical contribution to the total hemoglobin signal change (ΔHbT). Similarly, the cortical contribution of the oxyhemoglobin signal change (ΔHbO) is equal to 73–79% of the cortical contribution to the ΔHbT signal. These results suggest that ΔHbT is far less sensitive to pial vein contamination and therefore, it is likely that the ΔHbT signal provides better spatial specificity and should be used instead of ΔHbO or ΔHbR to map cerebral activity with NIRS. While different stimuli will result in different pial vein contributions, our finger tapping results do reveal the importance of considering the pial contribution. PMID:22036999

Impact of extracranial contamination on regional cerebral oxygen saturation: a comparison of three cerebral oximetry technologies.

PubMed

Davie, Sophie N; Grocott, Hilary P

2012-04-01

Cerebral oximetry is a noninvasive technology using near-infrared spectroscopy (NIRS) to estimate regional cerebral oxygen saturation. Although NIRS cerebral oximetry is being increasingly used in many clinical settings, interdevice technologic differences suggest potential variation in the ability to accurately acquire brain oxygenation signals. The primary objective of this study was to determine if NIRS-derived regional cerebral oxygen saturation measurements accurately account for oxygen saturation contamination from extracranial tissue. Twelve healthy volunteers had each of three NIRS devices (FORE-SIGHT [CAS Medical Systems Inc; Brandford, CT], INVOS 5100C-PB [Covidien; Boulder, CO], and EQUANOX Classic 7600 [Nonin Medical Inc; Plymouth, MN]) randomly applied to the forehead. After this, a circumferential pneumatic head cuff was positioned such that when inflated, hypoxia-ischemia would be produced in the extracranial scalp tissue beneath the NIRS cerebral oximeters. Comparisons among the three devices were made of the NIRS measurements before and following hypoxia-ischemia produced in the scalp tissue with inflation of the head cuff. The induction of extracranial hypoxia-ischemia resulted in a significant reduction in regional cerebral oxygen saturation measurements in all three NIRS devices studied. At 5 min postinflation of the pneumatic head cuff, the INVOS demonstrated a 16.6 ± 9.6% (mean ± SD) decrease from its baseline (P = 0.0001), the FORE-SIGHT an 11.8 ± 5.3% decrease from its baseline (P < 0.0001), and the EQUANOX a 6.8 ± 6.0% reduction from baseline (P = 0.0025). Extracranial contamination appears to significantly affect NIRS measurements of cerebral oxygen saturation. Although the clinical implications of these apparent inaccuracies require further study, they suggest that the oxygen saturation measurements provided by cerebral oximetry do not solely reflect that of the brain alone.

Fatty acids and fat-soluble vitamins in ewe's milk predicted by near infrared reflectance spectroscopy. Determination of seasonality.

PubMed

Revilla, I; Escuredo, O; González-Martín, M I; Palacios, C

2017-01-01

The aim of the present work was to determine the fatty acid and fat-soluble vitamin composition and the season of ewe's milk production using NIR spectroscopy. 219 ewe's milk samples from different breeds and feeding regimes were taken each month over one year. Fatty acids were analyzed by gas chromatography, and retinol and α-, and γ-tocopherol by liquid chromatography. The results showed that the quantification was more accurate for the milk dried on paper, except for vitamins. Calibration statistical descriptors on milk dried on paper were good for capric, lauric, myristic, palmitoleic, stearic and oleic acids, and acceptable for caprilic, undecanoic, 9c, 11tCLA, ΣCLA, PUFA, ω3, ω6, retinol and α-tocopherol. The equations for the discrimination of seasonality was obtained using the partial least squares discriminant analysis (PLSDA) algorithm. 93% of winter samples and 89% of summer samples were correctly classified using the NIR spectra of milk dried on paper. Copyright © 2016 Elsevier Ltd. All rights reserved.

Species authentication and geographical origin discrimination of herbal medicines by near infrared spectroscopy: A review.

PubMed

Wang, Pei; Yu, Zhiguo

2015-10-01

Near infrared (NIR) spectroscopy as a rapid and nondestructive analytical technique, integrated with chemometrics, is a powerful process analytical tool for the pharmaceutical industry and is becoming an attractive complementary technique for herbal medicine analysis. This review mainly focuses on the recent applications of NIR spectroscopy in species authentication of herbal medicines and their geographical origin discrimination.

Predicting cotton stelometer fiber strength by fourier transform infrared spectroscopy

USDA-ARS?s Scientific Manuscript database

The strength of cotton fibers is one of several important end-use characteristics. In routine programs, it has been mostly assessed by automation-oriented high volume instrument (HVI) system. An alternative method for cotton strength is near infrared (NIR) spectroscopy. Although previous NIR models ...

Application of near infrared spectroscopy to the analysis and fast quality assessment of traditional Chinese medicinal products

PubMed Central

Zhang, Chao; Su, Jinghua

2014-01-01

Near infrared spectroscopy (NIRS) has been widely applied in both qualitative and quantitative analysis. There is growing interest in its application to traditional Chinese medicine (TCM) and a review of recent developments in the field is timely. To present an overview of recent applications of NIRS to the identification, classification and analysis of TCM products, studies describing the application of NIRS to TCM products are classified into those involving qualitative and quantitative analysis. In addition, the application of NIRS to the detection of illegal additives and the rapid assessment of quality of TCMs by fast inspection are also described. This review covers over 100 studies emphasizing the application of NIRS in different fields. Furthermore, basic analytical principles and specific examples are used to illustrate the feasibility and effectiveness of NIRS in pattern identification. NIRS provides an effective and powerful tool for the qualitative and quantitative analysis of TCM products. PMID:26579382

Near Infra-Red Spectroscopy to Reduce Prophylactic Fasciotomies for and Missed Cases of Acute Compartment Syndrome in Soldiers Injured in OEF/OIF

DTIC Science & Technology

2013-10-01

demonstrated that NIRS measurement of hemoglobin oxygen saturation in the tibial compartment provided reliable and sensitive correlation to increases...on 60 healthy participants. Our results indicated that NIRS was able to detect changes in oxygen saturation of muscle with exercise in all 60...Model 41 Introduction 42 Over the last two decades, tissue oxygenation saturation (StO2) measured by near infrared 43 spectroscopy (NIRS) has

Application of effective wavelengths and BP neural network for the discrimination of varieties of instant milk tea powders using visible and near infrared spectroscopy

NASA Astrophysics Data System (ADS)

Liu, Fei; He, Yong; Wang, Li

2007-11-01

In order to implement the fast discrimination of different milk tea powders with different internal qualities, visible and near infrared (Vis/NIR) spectroscopy combined with effective wavelengths (EWs) and BP neural network (BPNN) was investigated as a new approach. Five brands of milk teas were obtained and 225 samples were selected randomly for the calibration set, while 75 samples for the validation set. The EWs were selected according to x-loading weights and regression coefficients by PLS analysis after some preprocessing. A total of 18 EWs (400, 401, 452, 453, 502, 503, 534, 535, 594, 595, 635, 636, 688, 689, 987, 988, 995 and 996 nm) were selected as the inputs of BPNN model. The performance was validated by the calibration and validation sets. The threshold error of prediction was set as +/-0.1 and an excellent precision and recognition ratio of 100% for calibration set and 98.7% for validation set were achieved. The prediction results indicated that the EWs reflected the main characteristics of milk tea of different brands based on Vis/NIR spectroscopy and BPNN model, and the EWs would be useful for the development of portable instrument to discriminate the variety and detect the adulteration of instant milk tea powders.

Selection of the NIR region for a regression model of the ethanol concentration in fermentation process by an online NIR and mid-IR dual-region spectrometer and 2D heterospectral correlation spectroscopy.

PubMed

Nishii, Takashi; Genkawa, Takuma; Watari, Masahiro; Ozaki, Yukihiro

2012-01-01

A new selection procedure of an informative near-infrared (NIR) region for regression model building is proposed that uses an online NIR/mid-infrared (mid-IR) dual-region spectrometer in conjunction with two-dimensional (2D) NIR/mid-IR heterospectral correlation spectroscopy. In this procedure, both NIR and mid-IR spectra of a liquid sample are acquired sequentially during a reaction process using the NIR/mid-IR dual-region spectrometer; the 2D NIR/mid-IR heterospectral correlation spectrum is subsequently calculated from the obtained spectral data set. From the calculated 2D spectrum, a NIR region is selected that includes bands of high positive correlation intensity with mid-IR bands assigned to the analyte, and used for the construction of a regression model. To evaluate the performance of this procedure, a partial least-squares (PLS) regression model of the ethanol concentration in a fermentation process was constructed. During fermentation, NIR/mid-IR spectra in the 10000 - 1200 cm(-1) region were acquired every 3 min, and a 2D NIR/mid-IR heterospectral correlation spectrum was calculated to investigate the correlation intensity between the NIR and mid-IR bands. NIR regions that include bands at 4343, 4416, 5778, 5904, and 5955 cm(-1), which result from the combinations and overtones of the C-H group of ethanol, were selected for use in the PLS regression models, by taking the correlation intensity of a mid-IR band at 2985 cm(-1) arising from the CH(3) asymmetric stretching vibration mode of ethanol as a reference. The predicted results indicate that the ethanol concentrations calculated from the PLS regression models fit well to those obtained by high-performance liquid chromatography. Thus, it can be concluded that the selection procedure using the NIR/mid-IR dual-region spectrometer combined with 2D NIR/mid-IR heterospectral correlation spectroscopy is a powerful method for the construction of a reliable regression model.

Predicting water-holding capacity of intact chicken broiler breast fillets with Vis/NIR spectroscopy

USDA-ARS?s Scientific Manuscript database

The ability of using visible and near-infrared (Vis/NIR) spectroscopy to predict water-holding capacity (WHC) of intact chicken broiler breast fillets (pectoralis major) was assessed in this study. Boneless and skinless chicken fillets (214 in total) were procured from a commercial processing plant ...

Near-infrared muscle functional monitoring

NASA Astrophysics Data System (ADS)

Ferrari, Marco; De Blasi, Roberto A.; Ferrari, Adriano; Pizzi, Assunta; Quaresima, Valentina

1994-01-01

The oxygenation of human muscle tissue can be investigated using near IR spectroscopy (NIRS). Oxy and deoxy hemoglobin changes can be quantified combining attenuation measurements with pathlength data obtained by time resolved spectroscopy. This study reports the application of NIRS to non- invasive measurements of quadriceps oxygenation on muscular dystrophy patients during treadmill exercise.

Visible/near-infrared spectroscopy to predict water holding capacity in broiler breast meat

USDA-ARS?s Scientific Manuscript database

Visible/Near-infrared spectroscopy (Vis/NIRS) was examined as a tool for rapidly determining water holding capacity (WHC) in broiler breast meat. Both partial least squares (PLS) and principal component analysis (PCA) models were developed to relate Vis/NIRS spectra of 85 broiler breast meat sample...

Application of multispectral reflectance for early detection of tomato disease

NASA Astrophysics Data System (ADS)

Xu, Huirong; Zhu, Shengpan; Ying, Yibin; Jiang, Huanyu

2006-10-01

Automatic diagnosis of plant disease is important for plant management and environmental preservation in the future. The objective of this study is to use multispectral reflectance measurements to make an early discrimination between the healthy and infected plants by the strain of tobacco mosaic virus (TMV-U1) infection. There were reflectance changes in the visible (VIS) and near infrared spectroscopy (NIR) between the healthy and infected plants. Discriminant models were developed using discriminant partial least squares (DPLS) and Mahalanobis distance (MD). The DPLS models had a root mean square error of calibration (RMSEC) of 0.397 and correlation coefficient (r) of 0.59 and the MD model correctly classified 86.7% healthy plants and up to 91.7% infected plants.

Noninvasive detection of change in skeletal muscle oxygenation during incremental exercise with near-infrared spectroscopy

NASA Astrophysics Data System (ADS)

Liu, Fang; Luo, Qingming; Xu, Guodong; Li, Pengcheng

2003-12-01

Near infrared spectroscopy (NIRS) has been developed as a non-invasive method to assess O2 delivery, O2 consumption and blood flow, in diverse local muscle groups at rest and during exercise. The aim of this study was to investigate local O2 consumption in exercising muscle by use of near-infrared spectroscopy (NIRS). Ten elite athletes of different sport items were tested in rest and during step incremental load exercise. Local variations of quadriceps muscles were investigated with our wireless NIRS blood oxygen monitor system. The results show that the changes of blood oxygen relate on the sport items, type of muscle, kinetic capacity et al. These results indicate that NIRS is a potential useful tool to detect local muscle oxygenation and blood flow profiles; therefore it might be easily applied for evaluating the effect of athletes training.

Near-infrared imaging of secondary caries lesions around composite restorations at wavelengths from 1300-1700-nm.

PubMed

Simon, Jacob C; A Lucas, Seth; Lee, Robert C; Darling, Cynthia L; Staninec, Michal; Vaderhobli, Ram; Pelzner, Roger; Fried, Daniel

2016-04-01

Current clinical methods for diagnosing secondary caries are unreliable for identifying the early stages of decay around restorative materials. The objective of this study was to access the integrity of restoration margins in natural teeth using near-infrared (NIR) reflectance and transillumination images at wavelengths between 1300 and 1700-nm and to determine the optimal NIR wavelengths for discriminating composite materials from dental hard tissues. Twelve composite margins (n=12) consisting of class I, II and V restorations were chosen from ten extracted teeth. The samples were imaged in vitro using NIR transillumination and reflectance, polarization sensitive optical coherence tomography (PS-OCT) and a high-magnification digital microscope. Samples were serially sectioned into 200-μm slices for histological analysis using polarized light microscopy (PLM) and transverse microradiography (TMR). Two independent examiners evaluated the presence of demineralization at the sample margin using visible detection with 10× magnification and NIR images presented digitally. Composite restorations were placed in sixteen sound teeth (n=16) and imaged at multiple NIR wavelengths ranging from λ=1300 to 1700-nm using NIR transillumination. The image contrast was calculated between the composite and sound tooth structure. Intensity changes in NIR images at wavelengths ranging from 1300 to 1700-nm correlate with increased mineral loss measured using TMR. NIR reflectance and transillumination at wavelengths coincident with increased water absorption yielded significantly higher (P<0.001) contrast between sound enamel and adjacent demineralized enamel. In addition, NIR reflectance exhibited significantly higher (P<0.01) contrast between sound enamel and adjacent composite restorations than visible reflectance. This study shows that NIR imaging is well suited for the rapid screening of secondary caries lesions. Copyright © 2016 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Near-infrared Imaging of Secondary Caries Lesions around Composite Restorations at Wavelengths from 1300–1700-nm

PubMed Central

Simon, Jacob C.; Lucas, Seth; Lee, Robert; Darling, Cynthia L.; Staninec, Michal; Vanderhobli, Ram; Pelzner, Roger; Fried, Daniel

2016-01-01

Background and Objectives Current clinical methods for diagnosing secondary caries are unreliable for identifying the early stages of decay around restorative materials. The objective of this study was to access the integrity of restoration margins in natural teeth using near-infrared (NIR) reflectance and transillumination images at wavelengths between 1300–1700-nm and to determine the optimal NIR wavelengths for discriminating composite materials from dental hard tissues. Materials and Methods Twelve composite margins (n=12) consisting of class I, II & V restorations were chosen from ten extracted teeth. The samples were imaged in vitro using NIR transillumination and reflectance, polarization sensitive optical coherence tomography (PS-OCT) and a high-magnification digital microscope. Samples were serially sectioned into 200–μm slices for histological analysis using polarized light microscopy (PLM) and transverse microradiography (TMR). Two independent examiners evaluated the presence of demineralization at the sample margin using visible detection with 10× magnification and NIR images presented digitally. Composite restorations were placed in sixteen sound teeth (n=16) and imaged at multiple NIR wavelengths ranging from λ=1300–1700-nm using NIR transillumination. The image contrast was calculated between the composite and sound tooth structure. Results Intensity changes in NIR images at wavelengths ranging from 1300–1700-nm correlate with increased mineral loss measured using TMR. NIR reflectance and transillumination at wavelengths coincident with increased water absorption yielded significantly higher (P<0.001) contrast between sound enamel and adjacent demineralized enamel. In addition, NIR reflectance exhibited significantly higher (P<0.01) contrast between sound enamel and adjacent composite restorations than visible reflectance. Significance This study shows that NIR imaging is well suited for the rapid screening of secondary caries lesions. PMID:26876234

A new optical method coupling light polarization and Vis-NIR spectroscopy to improve the measured absorbance signal's quality of soil samples.

NASA Astrophysics Data System (ADS)

Gobrecht, Alexia; Bendoula, Ryad; Roger, Jean-Michel; Bellon-Maurel, Véronique

2014-05-01

Visible - Near-infrared spectroscopy (Vis-NIRS) is now commonly used to measure different physical and chemical parameters of soils, including carbon content. However, prediction model accuracy is insufficient for Vis-NIRS to replace routine laboratory analysis. One of the biggest issues this technique is facing up to is light scattering due to soil particles. It causes departure in the assumed linear relationship between the Absorbance spectrum and the concentration of the chemicals of interest as stated by Beer-Lambert's Law, which underpins the calibration models. Therefore it becomes essential to improve the metrological quality of the measured signal in order to optimize calibration as light/matter interactions are at the basis of the resulting linear modeling. Optics can help to mitigate scattering effect on the signal. We put forward a new optical setup coupling linearly polarized light with a Vis-NIR spectrometer to free the measured spectra from multi-scattering effect. The corrected measured spectrum was then used to compute an Absorbance spectrum of the sample, using Dahm's Equation in the frame of the Representative Layer Theory. This method has been previously tested and validated on liquid (milk+ dye) and powdered (sand + dye) samples showing scattering (and absorbing) properties. The obtained Absorbance was a very good approximation of the Beer-Lambert's law absorbance. Here, we tested the method on a set of 54 soil samples to predict Soil Organic Carbon content. In order to assess the signal quality improvement by this method, we built and compared calibration models using Partial Least Square (PLS) algorithm. The prediction model built from new Absorbance spectrum outperformed the model built with the classical Absorbance traditionally obtained with Vis-NIR diffuse reflectance. This study is a good illustration of the high influence of signal quality on prediction model's performances.

Near-Infrared Spectroscopy Using a Supercontinuum Laser: Application to Long Wavelength Transmission Spectra of Barley Endosperm and Oil.

PubMed

Ringsted, Tine; Dupont, Sune; Ramsay, Jacob; Jespersen, Birthe Møller; Sørensen, Klavs Martin; Keiding, Søren Rud; Engelsen, Søren Balling

2016-07-01

The supercontinuum laser is a new type of light source, which combines the collimation and intensity of a laser with the broad spectral region of a lamp. Using such a source therefore makes it possible to focus the light onto small sample areas without losing intensity and thus facilitate either rapid or high-intensity measurements. Single seed transmission analysis in the long wavelength (LW) near-infrared (NIR) region is one area that might benefit from a brighter light source such as the supercontinuum laser. This study is aimed at building an experimental spectrometer consisting of a supercontinuum laser source and a dispersive monochromator in order to investigate its capability to measure the barley endosperm using transmission experiments in the LW NIR region. So far, barley and wheat seeds have only been studied using NIR transmission in the short wavelength region up to 1100 nm. However, the region in the range of 2260-2380 nm has previously shown to be particularly useful in differentiating barley phenotypes using NIR spectroscopy in reflectance mode. In the present study, 350 seeds (consisting of 70 seeds from each of five barley genotypes) in 1 mm slices were measured by NIR transmission in the range of 2235-2381 nm and oils from the same five barley genotypes were measured in a cuvette with a 1 mm path length in the range of 2003-2497 nm. The spectra of the barley seeds could be classified according to genotypes by principal component analysis; and spectral covariances with reference analysis of moisture, β-glucan, starch, protein and lipid were established. The spectral variations of the barley oils were compared to the fatty acid compositions as measured using gas chromotography-mass spectrometry (GC-MS). © The Author(s) 2016.

Assessment of hyaline cartilage matrix composition using near infrared spectroscopy.

PubMed

Palukuru, Uday P; McGoverin, Cushla M; Pleshko, Nancy

2014-09-01

Changes in the composition of the extracellular matrix (ECM) are characteristic of injury or disease in cartilage tissue. Various imaging modalities and biochemical techniques have been used to assess the changes in cartilage tissue but lack adequate sensitivity, or in the case of biochemical techniques, result in destruction of the sample. Fourier transform near infrared (FT-NIR) spectroscopy has shown promise for the study of cartilage composition. In the current study NIR spectroscopy was used to identify the contributions of individual components of cartilage in the NIR spectra by assessment of the major cartilage components, collagen and chondroitin sulfate, in pure component mixtures. The NIR spectra were obtained using homogenous pellets made by dilution with potassium bromide. A partial least squares (PLS) model was calculated to predict composition in bovine cartilage samples. Characteristic absorbance peaks between 4000 and 5000 cm(-1) could be attributed to components of cartilage, i.e. collagen and chondroitin sulfate. Prediction of the amount of collagen and chondroitin sulfate in tissues was possible within 8% (w/dw) of values obtained by gold standard biochemical assessment. These results support the use of NIR spectroscopy for in vitro and in vivo applications to assess matrix composition of cartilage tissues, especially when tissue destruction should be avoided. Copyright © 2014. Published by Elsevier B.V.

Sensitivity of near-infrared spectroscopy and diffuse correlation spectroscopy to brain hemodynamics: simulations and experimental findings during hypercapnia

PubMed Central

Selb, Juliette; Boas, David A.; Chan, Suk-Tak; Evans, Karleyton C.; Buckley, Erin M.; Carp, Stefan A.

2014-01-01

Abstract. Near-infrared spectroscopy (NIRS) and diffuse correlation spectroscopy (DCS) are two diffuse optical technologies for brain imaging that are sensitive to changes in hemoglobin concentrations and blood flow, respectively. Measurements for both modalities are acquired on the scalp, and therefore hemodynamic processes in the extracerebral vasculature confound the interpretation of cortical hemodynamic signals. The sensitivity of NIRS to the brain versus the extracerebral tissue and the contrast-to-noise ratio (CNR) of NIRS to cerebral hemodynamic responses have been well characterized, but the same has not been evaluated for DCS. This is important to assess in order to understand their relative capabilities in measuring cerebral physiological changes. We present Monte Carlo simulations on a head model that demonstrate that the relative brain-to-scalp sensitivity is about three times higher for DCS (0.3 at 3 cm) than for NIRS (0.1 at 3 cm). However, because DCS has higher levels of noise due to photon-counting detection, the CNR is similar for both modalities in response to a physiologically realistic simulation of brain activation. Even so, we also observed higher CNR of the hemodynamic response during graded hypercapnia in adult subjects with DCS than with NIRS. PMID:25453036

Intraoperative near-infrared fluorescence imaging and spectroscopy identifies residual tumor cells in wounds

NASA Astrophysics Data System (ADS)

Holt, David; Parthasarathy, Ashwin B.; Okusanya, Olugbenga; Keating, Jane; Venegas, Ollin; Deshpande, Charuhas; Karakousis, Giorgos; Madajewski, Brian; Durham, Amy; Nie, Shuming; Yodh, Arjun G.; Singhal, Sunil

2015-07-01

Surgery is the most effective method to cure patients with solid tumors, and 50% of all cancer patients undergo resection. Local recurrences are due to tumor cells remaining in the wound, thus we explore near-infrared (NIR) fluorescence spectroscopy and imaging to identify residual cancer cells after surgery. Fifteen canines and two human patients with spontaneously occurring sarcomas underwent intraoperative imaging. During the operation, the wounds were interrogated with NIR fluorescence imaging and spectroscopy. NIR monitoring identified the presence or absence of residual tumor cells after surgery in 14/15 canines with a mean fluorescence signal-to-background ratio (SBR) of ˜16. Ten animals showed no residual tumor cells in the wound bed (mean SBR<2, P<0.001). None had a local recurrence at >1-year follow-up. In five animals, the mean SBR of the wound was >15, and histopathology confirmed tumor cells in the postsurgical wound in four/five canines. In the human pilot study, neither patient had residual tumor cells in the wound bed, and both remain disease free at >1.5-year follow up. Intraoperative NIR fluorescence imaging and spectroscopy identifies residual tumor cells in surgical wounds. These observations suggest that NIR imaging techniques may improve tumor resection during cancer operations.

Quality assessment of pharmaceutical tablet samples using Fourier transform near infrared spectroscopy and multivariate analysis

NASA Astrophysics Data System (ADS)

Kandpal, Lalit Mohan; Tewari, Jagdish; Gopinathan, Nishanth; Stolee, Jessica; Strong, Rick; Boulas, Pierre; Cho, Byoung-Kwan

2017-09-01

Determination of the content uniformity, assessed by the amount of an active pharmaceutical ingredient (API), and hardness of pharmaceutical materials is important for achieving a high-quality formulation and to ensure the intended therapeutic effects of the end-product. In this work, Fourier transform near infrared (FT-NIR) spectroscopy was used to determine the content uniformity and hardness of a pharmaceutical mini-tablet and standard tablet samples. Tablet samples were scanned using an FT-NIR instrument and tablet spectra were collected at wavelengths of 1000-2500 nm. Furthermore, multivariate analysis was applied to extract the relationship between the FT-NIR spectra and the measured parameters. The results of FT-NIR spectroscopy for API and hardness prediction were as precise as the reference high-performance liquid chromatography and mechanical hardness tests. For the prediction of mini-tablet API content, the highest coefficient of determination for the prediction (R2p) was found to be 0.99 with a standard error of prediction (SEP) of 0.72 mg. Moreover, the standard tablet hardness measurement had a R2p value of 0.91 with an SEP of 0.25 kg. These results suggest that FT-NIR spectroscopy is an alternative and accurate nondestructive measurement tool for the detection of the chemical and physical properties of pharmaceutical samples.

Intraoperative near-infrared fluorescence imaging and spectroscopy identifies residual tumor cells in wounds

PubMed Central

Holt, David; Parthasarathy, Ashwin B.; Okusanya, Olugbenga; Keating, Jane; Venegas, Ollin; Deshpande, Charuhas; Karakousis, Giorgos; Madajewski, Brian; Durham, Amy; Nie, Shuming; Yodh, Arjun G.; Singhal, Sunil

2015-01-01

Abstract. Surgery is the most effective method to cure patients with solid tumors, and 50% of all cancer patients undergo resection. Local recurrences are due to tumor cells remaining in the wound, thus we explore near-infrared (NIR) fluorescence spectroscopy and imaging to identify residual cancer cells after surgery. Fifteen canines and two human patients with spontaneously occurring sarcomas underwent intraoperative imaging. During the operation, the wounds were interrogated with NIR fluorescence imaging and spectroscopy. NIR monitoring identified the presence or absence of residual tumor cells after surgery in 14/15 canines with a mean fluorescence signal-to-background ratio (SBR) of ∼16. Ten animals showed no residual tumor cells in the wound bed (mean SBR<2, P<0.001). None had a local recurrence at >1-year follow-up. In five animals, the mean SBR of the wound was >15, and histopathology confirmed tumor cells in the postsurgical wound in four/five canines. In the human pilot study, neither patient had residual tumor cells in the wound bed, and both remain disease free at >1.5-year follow up. Intraoperative NIR fluorescence imaging and spectroscopy identifies residual tumor cells in surgical wounds. These observations suggest that NIR imaging techniques may improve tumor resection during cancer operations. PMID:26160347

Robust new NIRS coupled with multivariate methods for the detection and quantification of tallow adulteration in clarified butter samples.

PubMed

Mabood, Fazal; Abbas, Ghulam; Jabeen, Farah; Naureen, Zakira; Al-Harrasi, Ahmed; Hamaed, Ahmad M; Hussain, Javid; Al-Nabhani, Mahmood; Al Shukaili, Maryam S; Khan, Alamgir; Manzoor, Suryyia

2018-03-01

Cows' butterfat may be adulterated with animal fat materials like tallow which causes increased serum cholesterol and triglycerides levels upon consumption. There is no reliable technique to detect and quantify tallow adulteration in butter samples in a feasible way. In this study a highly sensitive near-infrared (NIR) spectroscopy combined with chemometric methods was developed to detect as well as quantify the level of tallow adulterant in clarified butter samples. For this investigation the pure clarified butter samples were intentionally adulterated with tallow at the following percentage levels: 1%, 3%, 5%, 7%, 9%, 11%, 13%, 15%, 17% and 20% (wt/wt). Altogether 99 clarified butter samples were used including nine pure samples (un-adulterated clarified butter) and 90 clarified butter samples adulterated with tallow. Each sample was analysed by using NIR spectroscopy in the reflection mode in the range 10,000-4000 cm -1 , at 2 cm -1 resolution and using the transflectance sample accessory which provided a total path length of 0.5 mm. Chemometric models including principal components analysis (PCA), partial least-squares discriminant analysis (PLSDA), and partial least-squares regressions (PLSR) were applied for statistical treatment of the obtained NIR spectral data. The PLSDA model was employed to differentiate pure butter samples from those adulterated with tallow. The employed model was then externally cross-validated by using a test set which included 30% of the total butter samples. The excellent performance of the model was proved by the low RMSEP value of 1.537% and the high correlation factor of 0.95. This newly developed method is robust, non-destructive, highly sensitive, and economical with very minor sample preparation and good ability to quantify less than 1.5% of tallow adulteration in clarified butter samples.

Modeling soil organic matter (SOM) from satellite data using VISNIR-SWIR spectroscopy and PLS regression with step-down variable selection algorithm: case study of Campos Amazonicos National Park savanna enclave, Brazil

NASA Astrophysics Data System (ADS)

Rosero-Vlasova, O.; Borini Alves, D.; Vlassova, L.; Perez-Cabello, F.; Montorio Lloveria, R.

2017-10-01

Deforestation in Amazon basin due, among other factors, to frequent wildfires demands continuous post-fire monitoring of soil and vegetation. Thus, the study posed two objectives: (1) evaluate the capacity of Visible - Near InfraRed - ShortWave InfraRed (VIS-NIR-SWIR) spectroscopy to estimate soil organic matter (SOM) in fire-affected soils, and (2) assess the feasibility of SOM mapping from satellite images. For this purpose, 30 soil samples (surface layer) were collected in 2016 in areas of grass and riparian vegetation of Campos Amazonicos National Park, Brazil, repeatedly affected by wildfires. Standard laboratory procedures were applied to determine SOM. Reflectance spectra of soils were obtained in controlled laboratory conditions using Fieldspec4 spectroradiometer (spectral range 350nm- 2500nm). Measured spectra were resampled to simulate reflectances for Landsat-8, Sentinel-2 and EnMap spectral bands, used as predictors in SOM models developed using Partial Least Squares regression and step-down variable selection algorithm (PLSR-SD). The best fit was achieved with models based on reflectances simulated for EnMap bands (R2=0.93; R2cv=0.82 and NMSE=0.07; NMSEcv=0.19). The model uses only 8 out of 244 predictors (bands) chosen by the step-down variable selection algorithm. The least reliable estimates (R2=0.55 and R2cv=0.40 and NMSE=0.43; NMSEcv=0.60) resulted from Landsat model, while Sentinel-2 model showed R2=0.68 and R2cv=0.63; NMSE=0.31 and NMSEcv=0.38. The results confirm high potential of VIS-NIR-SWIR spectroscopy for SOM estimation. Application of step-down produces sparser and better-fit models. Finally, SOM can be estimated with an acceptable accuracy (NMSE 0.35) from EnMap and Sentinel-2 data enabling mapping and analysis of impacts of repeated wildfires on soils in the study area.

Near infrared spectroscopy for high-throughput characterization of Shea tree (Vitellaria paradoxa) nut fat profiles.

PubMed

Davrieux, Fabrice; Allal, François; Piombo, Georges; Kelly, Bokary; Okulo, John B; Thiam, Massamba; Diallo, Ousmane B; Bouvet, Jean-Marc

2010-07-14

The Shea tree (Vitellaria paradoxa) is a major tree species in African agroforestry systems. Butter extracted from its nuts offers an opportunity for sustainable development in Sudanian countries and an attractive potential for the food and cosmetics industries. The purpose of this study was to develop near-infrared spectroscopy (NIRS) calibrations to characterize Shea nut fat profiles. Powders prepared from nuts collected from 624 trees in five African countries (Senegal, Mali, Burkina Faso, Ghana and Uganda) were analyzed for moisture content, fat content using solvent extraction, and fatty acid profiles using gas chromatography. Results confirmed the differences between East and West African Shea nut fat composition: eastern nuts had significantly higher fat and oleic acid contents. Near infrared reflectance spectra were recorded for each sample. Ten percent of the samples were randomly selected for validation and the remaining samples used for calibration. For each constituent, calibration equations were developed using modified partial least squares (MPLS) regression. The equation performances were evaluated using the ratio performance to deviation (RPD(p)) and R(p)(2) parameters, obtained by comparison of the validation set NIR predictions and corresponding laboratory values. Moisture (RPD(p) = 4.45; R(p)(2) = 0.95) and fat (RPD(p) = 5.6; R(p)(2) = 0.97) calibrations enabled accurate determination of these traits. NIR models for stearic (RPD(p) = 6.26; R(p)(2) = 0.98) and oleic (RPD(p) = 7.91; R(p)(2) = 0.99) acids were highly efficient and enabled sharp characterization of these two major Shea butter fatty acids. This study demonstrated the ability of near-infrared spectroscopy for high-throughput phenotyping of Shea nuts.

Comparability of Red/Near-Infrared Reflectance and NDVI Based on the Spectral Response Function between MODIS and 30 Other Satellite Sensors Using Rice Canopy Spectra

PubMed Central

Huang, Weijiao; Huang, Jingfeng; Wang, Xiuzhen; Wang, Fumin; Shi, Jingjing

2013-01-01

Long-term monitoring of regional and global environment changes often depends on the combined use of multi-source sensor data. The most widely used vegetation index is the normalized difference vegetation index (NDVI), which is a function of the red and near-infrared (NIR) spectral bands. The reflectance and NDVI data sets derived from different satellite sensor systems will not be directly comparable due to different spectral response functions (SRF), which has been recognized as one of the most important sources of uncertainty in the multi-sensor data analysis. This study quantified the influence of SRFs on the red and NIR reflectances and NDVI derived from 31 Earth observation satellite sensors. For this purpose, spectroradiometric measurements were performed for paddy rice grown under varied nitrogen levels and at different growth stages. The rice canopy reflectances were convoluted with the spectral response functions of various satellite instruments to simulate sensor-specific reflectances in the red and NIR channels. NDVI values were then calculated using the simulated red and NIR reflectances. The results showed that as compared to the Terra MODIS, the mean relative percentage difference (RPD) ranged from −12.67% to 36.30% for the red reflectance, −8.52% to −0.23% for the NIR reflectance, and −9.32% to 3.10% for the NDVI. The mean absolute percentage difference (APD) compared to the Terra MODIS ranged from 1.28% to 36.30% for the red reflectance, 0.84% to 8.71% for the NIR reflectance, and 0.59% to 9.32% for the NDVI. The lowest APD between MODIS and the other 30 satellite sensors was observed for Landsat5 TM for the red reflectance, CBERS02B CCD for the NIR reflectance and Landsat4 TM for the NDVI. In addition, the largest APD between MODIS and the other 30 satellite sensors was observed for IKONOS for the red reflectance, AVHRR1 onboard NOAA8 for the NIR reflectance and IKONOS for the NDVI. The results also indicated that AVHRRs onboard NOAA7-17 showed higher differences than did the other sensors with respect to MODIS. A series of optimum models were presented for remote sensing data assimilation between MODIS and other sensors. PMID:24287529

Comparability of red/near-infrared reflectance and NDVI based on the spectral response function between MODIS and 30 other satellite sensors using rice canopy spectra.

PubMed

Huang, Weijiao; Huang, Jingfeng; Wang, Xiuzhen; Wang, Fumin; Shi, Jingjing

2013-11-26

Long-term monitoring of regional and global environment changes often depends on the combined use of multi-source sensor data. The most widely used vegetation index is the normalized difference vegetation index (NDVI), which is a function of the red and near-infrared (NIR) spectral bands. The reflectance and NDVI data sets derived from different satellite sensor systems will not be directly comparable due to different spectral response functions (SRF), which has been recognized as one of the most important sources of uncertainty in the multi-sensor data analysis. This study quantified the influence of SRFs on the red and NIR reflectances and NDVI derived from 31 Earth observation satellite sensors. For this purpose, spectroradiometric measurements were performed for paddy rice grown under varied nitrogen levels and at different growth stages. The rice canopy reflectances were convoluted with the spectral response functions of various satellite instruments to simulate sensor-specific reflectances in the red and NIR channels. NDVI values were then calculated using the simulated red and NIR reflectances. The results showed that as compared to the Terra MODIS, the mean relative percentage difference (RPD) ranged from -12.67% to 36.30% for the red reflectance, -8.52% to -0.23% for the NIR reflectance, and -9.32% to 3.10% for the NDVI. The mean absolute percentage difference (APD) compared to the Terra MODIS ranged from 1.28% to 36.30% for the red reflectance, 0.84% to 8.71% for the NIR reflectance, and 0.59% to 9.32% for the NDVI. The lowest APD between MODIS and the other 30 satellite sensors was observed for Landsat5 TM for the red reflectance, CBERS02B CCD for the NIR reflectance and Landsat4 TM for the NDVI. In addition, the largest APD between MODIS and the other 30 satellite sensors was observed for IKONOS for the red reflectance, AVHRR1 onboard NOAA8 for the NIR reflectance and IKONOS for the NDVI. The results also indicated that AVHRRs onboard NOAA7-17 showed higher differences than did the other sensors with respect to MODIS. A series of optimum models were presented for remote sensing data assimilation between MODIS and other sensors.

Natural gas pipeline leak detector based on NIR diode laser absorption spectroscopy.

PubMed

Gao, Xiaoming; Fan, Hong; Huang, Teng; Wang, Xia; Bao, Jian; Li, Xiaoyun; Huang, Wei; Zhang, Weijun

2006-09-01

The paper reports on the development of an integrated natural gas pipeline leak detector based on diode laser absorption spectroscopy. The detector transmits a 1.653 microm DFB diode laser with 10 mW and detects a fraction of the backscatter reflected from the topographic targets. To eliminate the effect of topographic scatter targets, a ratio detection technique was used. Wavelength modulation and harmonic detection were used to improve the detection sensitivity. The experimental detection limit is 50 ppmm, remote detection for a distance up to 20 m away topographic scatter target is demonstrated. Using a known simulative leak pipe, minimum detectable pipe leak flux is less than 10 ml/min.

Sleep apnea termination decreases cerebral blood volume: a near-infrared spectroscopy case study

NASA Astrophysics Data System (ADS)

Virtanen, Jaakko; Noponen, Tommi; Salmi, Tapani; Toppila, Jussi; Meriläinen, Pekka

2009-07-01

Medical near-infrared spectroscopy (NIRS) can be used to estimate cerebral haemodynamic changes non-invasively. Sleep apnea is a common sleep disorder where repetitive pauses in breathing decrease the quality of sleep and exposes the individual to various health problems. We have measured oxygenated and deoxygenated haemoglobin concentration changes during apneic events in sleep from the forehead of one subject using NIRS and used principal component analysis to extract extracerebral and cortical haemodynamic changes from NIRS signals. Comparison of NIRS signals with EEG, bioimpedance, and pulse oximetry data suggests that termination of apnea leads to decreases in cerebral blood volume and flow that may be related to neurological arousal via neurovascular coupling.

2D Vis/NIR correlation spectroscopy of cooked chicken meats

NASA Astrophysics Data System (ADS)

Liu, Yongliang; Chen, Yud-Ren; Ozaki, Yukihiro

2000-03-01

Cooking of chicken meats was investigated by the generalized two-dimensional visible/near-infrared (2D Vis/NIR) correlation spectroscopy. Synchronous and asynchronous spectra in the 400-700 nm visible region suggested that the 445 and 560 nm bands be ascribed to deoxymyoglobin and oxymyoglobin, and at least one of the 475, 520, and 585 nm bands is assignable to the denatured species (metmyoglobin). The asynchronous 2D NIR correlation spectrum showed that CH bands change their spectral intensities before the OH/NH groups during the cooking process, indicating that CH fractions are easily oxidized and degraded. In addition, strong correlation peaks were observed correlating the bands in the visible and NIR spectral regions.

Rapid determination of acetic acid, furfural and 5-hydroxymethylfurfural in biomass hydrolysate using near-infrared spectroscopy

USDA-ARS?s Scientific Manuscript database

Near infrared spectroscopy (NIR) is a rapid detection technique that has been used to characterize biomass. The objective of this study was to develop suitable NIR models to predict the acetic acid, furfural, and 5-hydroxymethylfurfural (HMF) contents in biomass hydrolysates. Using a uniform distrib...

Optimisation of near-infrared reflectance model in measuring protein and amylose content of rice flour.

PubMed

Xie, L H; Tang, S Q; Chen, N; Luo, J; Jiao, G A; Shao, G N; Wei, X J; Hu, P S

2014-01-01

Near-infrared reflectance spectroscopy (NIRS) has been used to predict the cooking quality parameters of rice, such as the protein (PC) and amylose content (AC). Using brown and milled flours from 519 rice samples representing a wide range of grain qualities, this study was to compare the calibration models generated by different mathematical, preprocessing treatments, and combinations of different regression algorithm. A modified partial least squares model (MPLS) with the mathematic treatment "2, 8, 8, 2" (2nd order derivative computed based on 8 data points, and 8 and 2 data points in the 1st and 2nd smoothing, respectively) and inverse multiplicative scattering correction preprocessing treatment was identified as the best model for simultaneously measurement of PC and AC in brown flours. MPLS/"2, 8, 8, 2"/detrend preprocessing was identified as the best model for milled flours. The results indicated that NIRS could be useful in estimation of PC and AC of breeding lines in early generations of the breeding programs, and for the purposes of quality control in the food industry. Copyright © 2013 Elsevier Ltd. All rights reserved.

Rapid Measurement of Soil Carbon in Rice Paddy Field of Lombok Island Indonesia Using Near Infrared Technology

NASA Astrophysics Data System (ADS)

Kusumo, B. H.; Sukartono, S.; Bustan, B.

2018-02-01

Measuring soil organic carbon (C) using conventional analysis is tedious procedure, time consuming and expensive. It is needed simple procedure which is cheap and saves time. Near infrared technology offers rapid procedure as it works based on the soil spectral reflectance and without any chemicals. The aim of this research is to test whether this technology able to rapidly measure soil organic C in rice paddy field. Soil samples were collected from rice paddy field of Lombok Island Indonesia, and the coordinates of the samples were recorded. Parts of the samples were analysed using conventional analysis (Walkley and Black) and some other parts were scanned using near infrared spectroscopy (NIRS) for soil spectral collection. Partial Least Square Regression (PLSR) Models were developed using data of soil C analysed using conventional analysis and data from soil spectral reflectance. The models were moderately successful to measure soil C in rice paddy field of Lombok Island. This shows that the NIR technology can be further used to monitor the C change in rice paddy soil.

Laboratory and Field Spectroscopy of Moon analogue material

NASA Astrophysics Data System (ADS)

Offringa, Marloes; Foing, Bernard H.

2016-07-01

Samples derived from terrestrial analogue sites are studied to gain insight into lunar processes in their geological context (Foing, Stoker, Ehrenfreund, 2011). For this study samples from the volcanic region of the Eifel, Germany collected during our latest field campaigns in November 2015 and February 2016 (Foing et al., 2010), are analyzed with a variety of spectrometers. The aim is to obtain a database of analyzed samples that could be used as a reference for future in situ measurements. We also use a documented set of Moon-Mars relevant minerals curated at VU Amsterdam. We are using systematically for all samples UV-VIS and NIR reflectance spectrometers, and sporadically a Fourier Transform Infrared (FTIR) spectrometer, an X-Ray Fluorescence (XRF) spectrometer and a Raman laser spectrometer on control samples. Calibration of the UV-VIS and NIR reflectance spectrometers is the main focus of this research in order to obtain the clearest spectra. The calibration of the UV-VIS and NIR reflectance spectrometers requires the use of a good light source as well as suitable optical fibers to create a signal that covers the widest range in wavelengths available. To eliminate noise towards the edges of this range, multiple measurements are averaged and data is processed by dividing the signal by reference spectra. Obtained spectra can be tested for accuracy by comparing them with stationary laboratory spectrometers such as the FTIR spectrometer. The Raman, UV-VIS and NIR are also used in combination with the ExoGeoLab mock-up lander during field campaigns (Foing, Stoker, Ehrenfreund, 2011) also brought again to Eifel in February 2016, to prove the applicability of the equipment in the field. Acknowledgements: we thank Dominic Doyle for ESTEC optical lab support, Euan Monaghan (Leiden U) for FTIR measurement support, Wim van Westrenen for access to VU samples, Oscar Kamps (Utrecht U./ESTEC), Aidan Cowley (EAC) and Matthias Sperl (DLR) for support discussions

Polarized near-infrared autofluorescence imaging combined with near-infrared diffuse reflectance imaging for improving colonic cancer detection.

PubMed

Shao, Xiaozhuo; Zheng, Wei; Huang, Zhiwei

2010-11-08

We evaluate the diagnostic feasibility of the integrated polarized near-infrared (NIR) autofluorescence (AF) and NIR diffuse reflectance (DR) imaging technique developed for colonic cancer detection. A total of 48 paired colonic tissue specimens (normal vs. cancer) were measured using the integrated NIR DR (850-1100 nm) and NIR AF imaging at the 785 nm laser excitation. The results showed that NIR AF intensities of cancer tissues are significantly lower than those of normal tissues (p<0.001, paired 2-sided Student's t-test, n=48). NIR AF imaging under polarization conditions gives a higher diagnostic accuracy (of ~92-94%) compared to non-polarized NIR AF imaging or NIR DR imaging. Further, the ratio imaging of NIR DR to NIR AF with polarization provides the best diagnostic accuracy (of ~96%) among the NIR AF and NIR DR imaging techniques. This work suggests that the integrated NIR AF/DR imaging under polarization condition has the potential to improve the early diagnosis and detection of malignant lesions in the colon.

Measurements of coherent hemodynamics to enrich the physiological information provided by near-infrared spectroscopy (NIRS) and functional MRI

NASA Astrophysics Data System (ADS)

Sassaroli, Angelo; Tgavalekos, Kristen; Pham, Thao; Krishnamurthy, Nishanth; Fantini, Sergio

2018-02-01

Hemodynamic-based neuroimaging techniques such as functional magnetic resonance imaging (fMRI) and near-infrared spectroscopy (NIRS) sense hemoglobin concentration in cerebral tissue. The local concentration of hemoglobin, which is differentiated into oxy- and deoxy-hemoglobin by NIRS, features spontaneous oscillations over time scales of 10-100 s in response to a number of local and systemic physiological processes. If one of such processes becomes the dominant source of cerebral hemodynamics, there is a high coherence between this process and the associated hemodynamics. In this work, we report a method to identify such conditions of coherent hemodynamics, which may be exploited to study and quantify microvasculature and microcirculation properties. We discuss how a critical value of significant coherence may depend on the specific data collection scheme (for example, the total acquisition time) and the nature of the hemodynamic data (in particular, oxy- and deoxy-hemoglobin concentrations measured with NIRS show an intrinsic level of correlation that must be taken into account). A frequency-resolved study of coherent hemodynamics is the basis for the new technique of coherent hemodynamics spectroscopy (CHS), which aims to provide measures of cerebral blood flow and cerebral autoregulation. While these concepts apply in principle to both fMRI and NIRS data, in this article we focus on NIRS data.

Functional Near-Infrared Spectroscopy Signals Measure Neuronal Activity in the Cortex

NASA Technical Reports Server (NTRS)

Harrivel, Angela; Hearn, Tristan

2013-01-01

Functional near infrared spectroscopy (fNIRS) is an emerging optical neuroimaging technology that indirectly measures neuronal activity in the cortex via neurovascular coupling. It quantifies hemoglobin concentration ([Hb]) and thus measures the same hemodynamic response as functional magnetic resonance imaging (fMRI), but is portable, non-confining, relatively inexpensive, and is appropriate for long-duration monitoring and use at the bedside. Like fMRI, it is noninvasive and safe for repeated measurements. Patterns of [Hb] changes are used to classify cognitive state. Thus, fNIRS technology offers much potential for application in operational contexts. For instance, the use of fNIRS to detect the mental state of commercial aircraft operators in near real time could allow intelligent flight decks of the future to optimally support human performance in the interest of safety by responding to hazardous mental states of the operator. However, many opportunities remain for improving robustness and reliability. It is desirable to reduce the impact of motion and poor optical coupling of probes to the skin. Such artifacts degrade signal quality and thus cognitive state classification accuracy. Field application calls for further development of algorithms and filters for the automation of bad channel detection and dynamic artifact removal. This work introduces a novel adaptive filter method for automated real-time fNIRS signal quality detection and improvement. The output signal (after filtering) will have had contributions from motion and poor coupling reduced or removed, thus leaving a signal more indicative of changes due to hemodynamic brain activations of interest. Cognitive state classifications based on these signals reflect brain activity more reliably. The filter has been tested successfully with both synthetic and real human subject data, and requires no auxiliary measurement. This method could be implemented as a real-time filtering option or bad channel rejection feature of software used with frequency domain fNIRS instruments for signal acquisition and processing. Use of this method could improve the reliability of any operational or real-world application of fNIRS in which motion is an inherent part of the functional task of interest. Other optical diagnostic techniques (e.g., for NIR medical diagnosis) also may benefit from the reduction of probe motion artifact during any use in which motion avoidance would be impractical or limit usability.

A brief review on the history of human functional near-infrared spectroscopy (fNIRS) development and fields of application.

PubMed

Ferrari, Marco; Quaresima, Valentina

2012-11-01

This review is aimed at celebrating the upcoming 20th anniversary of the birth of human functional near-infrared spectroscopy (fNIRS). After the discovery in 1992 that the functional activation of the human cerebral cortex (due to oxygenation and hemodynamic changes) can be explored by NIRS, human functional brain mapping research has gained a new dimension. fNIRS or optical topography, or near-infrared imaging or diffuse optical imaging is used mainly to detect simultaneous changes in optical properties of the human cortex from multiple measurement sites and displays the results in the form of a map or image over a specific area. In order to place current fNIRS research in its proper context, this paper presents a brief historical overview of the events that have shaped the present status of fNIRS. In particular, technological progresses of fNIRS are highlighted (i.e., from single-site to multi-site functional cortical measurements (images)), introduction of the commercial multi-channel systems, recent commercial wireless instrumentation and more advanced prototypes. Copyright © 2012 Elsevier Inc. All rights reserved.

A brief review on the use of functional near-infrared spectroscopy (fNIRS) for language imaging studies in human newborns and adults.

PubMed

Quaresima, Valentina; Bisconti, Silvia; Ferrari, Marco

2012-05-01

Upon stimulation, real time maps of cortical hemodynamic responses can be obtained by non-invasive functional near-infrared spectroscopy (fNIRS) which measures changes in oxygenated and deoxygenated hemoglobin after positioning multiple sources and detectors over the human scalp. The current commercially available transportable fNIRS systems have a time resolution of 1-10 Hz, a depth sensitivity of about 1.5 cm, and a spatial resolution of about 1cm. The goal of this brief review is to report infants, children and adults fNIRS language studies. Since 1998, 60 studies have been published on cortical activation in the brain's classic language areas in children/adults as well as newborns using fNIRS instrumentations of different complexity. In addition, the basic principles of fNIRS including features, strengths, advantages, and limitations are summarized in terms that can be understood even by non specialists. Future prospects of fNIRS in the field of language processing imaging are highlighted. Copyright © 2011 Elsevier Inc. All rights reserved.

Development of motion resistant instrumentation for ambulatory near-infrared spectroscopy

PubMed Central

Zhang, Quan; Yan, Xiangguo; Strangman, Gary E.

2011-01-01

Ambulatory near-infrared spectroscopy (aNIRS) enables recording of systemic or tissue-specific hemodynamics and oxygenation during a person's normal activities. It has particular potential for the diagnosis and management of health problems with unpredictable and transient hemodynamic symptoms, or medical conditions requiring continuous, long-duration monitoring. aNIRS is also needed in conditions where regular monitoring or imaging cannot be applied, including remote environments such as during spaceflight or at high altitude. One key to the successful application of aNIRS is reducing the impact of motion artifacts in aNIRS recordings. In this paper, we describe the development of a novel prototype aNIRS monitor, called NINscan, and our efforts to reduce motion artifacts in aNIRS monitoring. Powered by 2 AA size batteries and weighting 350 g, NINscan records NIRS, ECG, respiration, and acceleration for up to 14 h at a 250 Hz sampling rate. The system's performance and resistance to motion is demonstrated by long term quantitative phantom tests, Valsalva maneuver tests, and multiparameter monitoring during parabolic flight and high altitude hiking. To the best of our knowledge, this is the first report of multiparameter aNIRS monitoring and its application in parabolic flight. PMID:21895335

What we can and cannot (yet) do with functional near infrared spectroscopy

PubMed Central

Strait, Megan; Scheutz, Matthias

2014-01-01

Functional near infrared spectroscopy (NIRS) is a relatively new technique complimentary to EEG for the development of brain-computer interfaces (BCIs). NIRS-based systems for detecting various cognitive and affective states such as mental and emotional stress have already been demonstrated in a range of adaptive human–computer interaction (HCI) applications. However, before NIRS-BCIs can be used reliably in realistic HCI settings, substantial challenges oncerning signal processing and modeling must be addressed. Although many of those challenges have been identified previously, the solutions to overcome them remain scant. In this paper, we first review what can be currently done with NIRS, specifically, NIRS-based approaches to measuring cognitive and affective user states as well as demonstrations of passive NIRS-BCIs. We then discuss some of the primary challenges these systems would face if deployed in more realistic settings, including detection latencies and motion artifacts. Lastly, we investigate the effects of some of these challenges on signal reliability via a quantitative comparison of three NIRS models. The hope is that this paper will actively engage researchers to acilitate the advancement of NIRS as a more robust and useful tool to the BCI community. PMID:24904261

Initial development of an NIR strain measurement technique in brittle geo-materials

NASA Astrophysics Data System (ADS)

Butcher, Emily; Gibson, Andrew; Benson, Philip

2016-04-01

Visible-Near Infrared Spectroscopy (VIS-NIR) is a technique developed for the non-contact measurement of compositional characteristics of surfaces. The technique is rapid, sensitive to change in surface topology and has found applications ranging from planetary geology, soil science, pharmacy to materials testing. The technique has also been used in a limited fashion to measure strain changes in rocks and minerals (Ord and Hobbs 1986). However, there have been few quantitative studies linking such changes in material strains (and other rock physics parameters) to the resulting VIS-NIT signature. This research seeks to determine whether improvements in VIS-NIR equipment means that such a technique is a viable method to measure strains in rock via this remote (non-contact) method. We report new experiments carried out using 40 mm Brazilian Tensile discs of Carrera Marble and Darley Dale Sandstone using an Instron 600LX in the University of Portsmouth Rock Mechanics Laboratory. The tensile test was selected for this experiment as the sample shape and sensor arrangements allow access to a 'flat' surface area throughout the test, allowing surface measurements to be continuously taken whilst the discs are strained to failure. An ASD Labspec 5000 with 25 mm foreoptic was used to collect reflectance spectra in the range 350-2500 nm during each tensile test. Results from Carrera Marble experiments show that reflectance at 2050 nm negatively correlates (by polynomial regression) with axial strain between 0.05-0.5%, with r2 of 0.99. Results from Darley Dale Sandstone data show that reflectance at 1970 nm positively correlates with axial deformation between 0.05-0.5%, with r2 of 0.98. Initial analyses suggests that the VIS-NIR possesses an output that scales in a quantifiable manner with rock strain, and shows promise as a technique for strain measurement. The method has particular application for allowing our laboratory measurements to "ground truth" data taken from drone and other remote sensing techniques that could employ this method. However, further work is underway to understand the exact nature of the correlations - for instance, whether reflectance is related to deformation to the mineral lattice, macro-surface or micro-surface.

Applications of Functional Near-Infrared Spectroscopy (fNIRS) in Studying Cognitive Development: The Case of Mathematics and Language.

PubMed

Soltanlou, Mojtaba; Sitnikova, Maria A; Nuerk, Hans-Christoph; Dresler, Thomas

2018-01-01

In this review, we aim to highlight the application of functional near-infrared spectroscopy (fNIRS) as a useful neuroimaging technique for the investigation of cognitive development. We focus on brain activation changes during the development of mathematics and language skills in schoolchildren. We discuss how technical limitations of common neuroimaging techniques such as functional magnetic resonance imaging (fMRI) have resulted in our limited understanding of neural changes during development, while fNIRS would be a suitable and child-friendly method to examine cognitive development. Moreover, this technique enables us to go to schools to collect large samples of data from children in ecologically valid settings. Furthermore, we report findings of fNIRS studies in the fields of mathematics and language, followed by a discussion of the outlook of fNIRS in these fields. We suggest fNIRS as an additional technique to track brain activation changes in the field of educational neuroscience.

Applications of Functional Near-Infrared Spectroscopy (fNIRS) in Studying Cognitive Development: The Case of Mathematics and Language

PubMed Central

Soltanlou, Mojtaba; Sitnikova, Maria A.; Nuerk, Hans-Christoph; Dresler, Thomas

2018-01-01

In this review, we aim to highlight the application of functional near-infrared spectroscopy (fNIRS) as a useful neuroimaging technique for the investigation of cognitive development. We focus on brain activation changes during the development of mathematics and language skills in schoolchildren. We discuss how technical limitations of common neuroimaging techniques such as functional magnetic resonance imaging (fMRI) have resulted in our limited understanding of neural changes during development, while fNIRS would be a suitable and child-friendly method to examine cognitive development. Moreover, this technique enables us to go to schools to collect large samples of data from children in ecologically valid settings. Furthermore, we report findings of fNIRS studies in the fields of mathematics and language, followed by a discussion of the outlook of fNIRS in these fields. We suggest fNIRS as an additional technique to track brain activation changes in the field of educational neuroscience. PMID:29666589

Development of near infrared spectrometer for gem materials study

NASA Astrophysics Data System (ADS)

Jindata, W.; Meesiri, W.; Wongkokua, W.

2015-07-01

Most of gem materials can be characterized by infrared absorption spectroscopy. Normally, mid infrared absorption technique has been applied for investigating fundamental vibrational modes. However, for some gem materials, such as tourmaline, NIR is a better choice due to differentiation. Most commercial NIR spectrometers employ complicated dispersive grating or Fourier transform techniques. In this work, we developed a filter type NIR spectrometer with the availability of high efficiency and low-cost narrow bandpass NIR interference filters to be taught in a physics laboratory. The instrument was designed for transmission-mode configuration. A 50W halogen lamp was used as NIR source. There were fourteen NIR filters mounted on a rotatory wheel for wavelength selection ranging from 1000-1650 nm with steps of 50 nm. A 1.0 mm diameter of InGaAs photodiode was used as the detector for the spectrometer. Hence, transparent gem materials can be used as samples for experiment. Student can learn vibrational absorption spectroscopy as well as Beer-Lambert law from the development of this instrument.

Application of reflectance colorimeter measurements and infrared spectroscopy methods to rapid and nondestructive evaluation of carotenoids content in apricot (Prunus armeniaca L.).

PubMed

Ruiz, David; Reich, Maryse; Bureau, Sylvie; Renard, Catherine M G C; Audergon, Jean-Marc

2008-07-09

The importance of carotenoid content in apricot (Prunus armeniaca L.) is recognized not only because of the color that they impart but also because of their protective activity against human diseases. Current methods to assess carotenoid content are time-consuming, expensive, and destructive. In this work, the application of rapid and nondestructive methods such as colorimeter measurements and infrared spectroscopy has been evaluated for carotenoid determination in apricot. Forty apricot genotypes covering a wide range of peel and flesh colors have been analyzed. Color measurements on the skin and flesh ( L*, a*, b*, hue, chroma, and a*/ b* ratio) as well as Fourier transform near-infrared spectroscopy (FT-NIR) on intact fruits and Fourier transform mid-infrared spectroscopy (FT-MIR) on ground flesh were correlated with the carotenoid content measured by high-performance liquid chromatography. A high variability in color values and carotenoid content was observed. Partial least squares regression analyses between beta-carotene content and provitamin A activity and color measurements showed a high fit in peel, flesh, and edible apricot portion (R(2) ranged from 0.81 to 0.91) and low prediction error. Regression equations were developed for predicting carotenoid content by using color values, which appeared as a simple, rapid, reliable, and nondestructive method. However, FT-NIR and FT-MIR models showed very low R(2) values and very high prediction errors for carotenoid content.

Correspondence of electroencephalography and near-infrared spectroscopy sensitivities to the cerebral cortex using a high-density layout

PubMed Central

Giacometti, Paolo; Diamond, Solomon G.

2014-01-01

Abstract. This study investigates the correspondence of the cortical sensitivity of electroencephalography (EEG) and near-infrared spectroscopy (NIRS). EEG forward model sensitivity to the cerebral cortex was calculated for 329 EEG electrodes following the 10-5 EEG positioning system using a segmented structural magnetic resonance imaging scan of a human subject. NIRS forward model sensitivity was calculated for the same subject using 156 NIRS source-detector pairs selected from 32 source and 32 detector optodes positioned on the scalp using a subset of the 10-5 EEG positioning system. Sensitivity correlations between colocalized NIRS source-detector pair groups and EEG channels yielded R=0.46±0.08. Groups of NIRS source-detector pairs with maximum correlations to EEG electrode sensitivities are tabulated. The mean correlation between the point spread functions for EEG and NIRS regions of interest (ROI) was R=0.43±0.07. Spherical ROIs with radii of 26 mm yielded the maximum correlation between EEG and NIRS averaged across all cortical mesh nodes. These sensitivity correlations between EEG and NIRS should be taken into account when designing multimodal studies of neurovascular coupling and when using NIRS as a statistical prior for EEG source localization. PMID:25558462

Using near-infrared spectroscopy to resolve the species, gender, age, and the presence of Wolbachia infection in laboratory-reared Drosophila

USDA-ARS?s Scientific Manuscript database

The aim of the study was to determine the accuracy of near-infrared spectroscopy (NIRS) in determining species, gender, age and the presence of the common endosymbiont Wolbachia in laboratory reared Drosophila. NIRS measures absorption of light by organic molecules. Initially, a calibration model wa...

Prediction of quality attributes of chicken breast fillets by using Vis/NIR spectroscopy combined with factor analysis method

USDA-ARS?s Scientific Manuscript database

Visible/near-infrared (Vis/NIR) spectroscopy with wavelength range between 400 and 2500 nm combined with factor analysis method was tested to predict quality attributes of chicken breast fillets. Quality attributes, including color (L*, a*, b*), pH, and drip loss were analyzed using factor analysis ...

The effects of water and lipids on NIR optical breast measurements

NASA Astrophysics Data System (ADS)

Cerussi, Albert E.; Bevilacqua, Frederic; Shah, Natasha; Jakubowski, Dorota B.; Berger, Andrew J.; Lanning, Ryan M.; Tromberg, Bruce J.

2001-06-01

Near infrared diffuse optical spectroscopy and imaging may enhance existing technologies for breast cancer screening, diagnosis, and treatment. NIR spectroscopy yields quantitative functional information that cannot be obtained with other non-invasive radiological techniques. In this study we focused upon the origins of this contrast in healthy breast, especially from water and lipids.

The application of near infrared (NIR) spectroscopy to inorganic preservative-treated wood

Treesearch

Chi-Leung So; Stan T. Lebow; Leslie H. Groom; Timothy G. Rials

2004-01-01

There is a growing need to find a rapid, inexpensive, and reliable method to distinguish between treated and untreated waste wood. This paper evaluates the ability of near infrared (NIR) spectroscopy with multivariate analysis (MVA) to distinguish preservative types and retentions. It is demonstrated that principal component analysis (PCA) can differentiate lumber...

Hemodynamic and Electrophysiological Connectivity in the Language System: Simultaneous Near-Infrared Spectroscopy and Electrocorticography Recordings during Cortical Stimulation

ERIC Educational Resources Information Center

Sato, Yosuke; Oishi, Makoto; Fukuda, Masafumi; Fujii, Yukihiko

2012-01-01

We applied near-infrared spectroscopy (NIRS) and electrocorticography (ECoG) recordings during cortical stimulation to a temporal lobe epilepsy patient who underwent subdural electrode implantation. Using NIRS, changes in blood concentrations of oxyhemoglobin (HbO[subscript 2]) and deoxyhemoglobin (HbR) during cortical stimulation of the left…

Functional Near-Infrared Spectroscopy for the Assessment of Speech Related Tasks

ERIC Educational Resources Information Center

Dieler, A. C.; Tupak, S. V.; Fallgatter, A. J.

2012-01-01

Over the past years functional near-infrared spectroscopy (fNIRS) has substantially contributed to the understanding of language and its neural correlates. In contrast to other imaging techniques, fNIRS is well suited to study language function in healthy and psychiatric populations due to its cheap and easy application in a quiet and natural…

Evaluating preservation methods for identifying Anopheles gambiae s.s. and Anopheles arabiensis complex mosquitoes species using near infra-red spectroscopy

USDA-ARS?s Scientific Manuscript database

Near infra-red spectroscopy (NIRS) has been successfully used on fresh and RNAlater® preserved Anopheles gambiae complex to identify sibling species and age. No preservation methods other than RNAlater® have been tested to preserve mosquitoes for species identification using NIRS. However, RNAlater®...

“Self-absorption” phenomenon in near-infrared Fourier transform Raman spectroscopy of cellulosic and lignocellulosic materials

Treesearch

Umesh P. Agarwal; Nancy Kawai

2005-01-01

While cellulosic and lignocellulosic materials have been studied using conventional Raman spectroscopy, availability of near-infrared (NIR) Fourier transform (FT) Raman instrumentation has made studying these materials much more convenient. This is especially true because the problem of laser-induced fluorescence can be avoided or minimized in FT- Raman (NIR Raman)...

Fiber micronaire, fineness and maturity predictions using NIR spectroscopy instruments on seed cotton and cotton fiber, in and outside of the laboratory

USDA-ARS?s Scientific Manuscript database

Micronaire is an important fiber quality parameter in the cotton industry. Micronaire is a function of maturity (the degree of the fiber secondary wall development) and fineness (linear density). Bench-top near infrared (NIR) spectroscopy has the ability to measure micronaire, maturity and fineness,...

A Brief Review of OPT101 Sensor Application in Near-Infrared Spectroscopy Instrumentation for Intensive Care Unit Clinics

PubMed Central

Li, Ting; Zhong, Fulin; Pan, Boan; Li, Zebin; Huang, Chong; Deng, Zishan

2017-01-01

The optoelectronic sensor OPT101 have merits in advanced optoelectronic response characteristics at wavelength range for medical near-infrared spectroscopy and small-size chip design with build-in trans-impedance amplifier. Our lab is devoted to developing a series of portable near-infrared spectroscopy (NIRS) devices embedded with OPT101 for applications in intensive care unit clinics, based on NIRS principle. Here we review the characteristics and advantages of OPT101 relative to clinical NIRS instrumentation, and the most recent achievements, including early-diagnosis and therapeutic effect evaluation of thrombus, noninvasive monitoring of patients' shock severity, and fatigue evaluation. The future prospect on OPT101 improvements in noninvasive clinical applications is also discussed. PMID:28757564

Variable selection based cotton bollworm odor spectroscopic detection

NASA Astrophysics Data System (ADS)

Lü, Chengxu; Gai, Shasha; Luo, Min; Zhao, Bo

2016-10-01

Aiming at rapid automatic pest detection based efficient and targeting pesticide application and shooting the trouble of reflectance spectral signal covered and attenuated by the solid plant, the possibility of near infrared spectroscopy (NIRS) detection on cotton bollworm odor is studied. Three cotton bollworm odor samples and 3 blank air gas samples were prepared. Different concentrations of cotton bollworm odor were prepared by mixing the above gas samples, resulting a calibration group of 62 samples and a validation group of 31 samples. Spectral collection system includes light source, optical fiber, sample chamber, spectrometer. Spectra were pretreated by baseline correction, modeled with partial least squares (PLS), and optimized by genetic algorithm (GA) and competitive adaptive reweighted sampling (CARS). Minor counts differences are found among spectra of different cotton bollworm odor concentrations. PLS model of all the variables was built presenting RMSEV of 14 and RV2 of 0.89, its theory basis is insect volatilizes specific odor, including pheromone and allelochemics, which are used for intra-specific and inter-specific communication and could be detected by NIR spectroscopy. 28 sensitive variables are selected by GA, presenting the model performance of RMSEV of 14 and RV2 of 0.90. Comparably, 8 sensitive variables are selected by CARS, presenting the model performance of RMSEV of 13 and RV2 of 0.92. CARS model employs only 1.5% variables presenting smaller error than that of all variable. Odor gas based NIR technique shows the potential for cotton bollworm detection.

Determination of polarimetric parameters of honey by near-infrared transflectance spectroscopy.

PubMed

García-Alvarez, M; Ceresuela, S; Huidobro, J F; Hermida, M; Rodríguez-Otero, J L

2002-01-30

NIR transflectance spectroscopy was used to determine polarimetric parameters (direct polarization, polarization after inversion, specific rotation in dry matter, and polarization due to nonmonosaccharides) and sucrose in honey. In total, 156 honey samples were collected during 1992 (45 samples), 1995 (56 samples), and 1996 (55 samples). Samples were analyzed by NIR spectroscopy and polarimetric methods. Calibration (118 samples) and validation (38 samples) sets were made up; honeys from the three years were included in both sets. Calibrations were performed by modified partial least-squares regression and scatter correction by standard normal variation and detrend methods. For direct polarization, polarization after inversion, specific rotation in dry matter, and polarization due to nonmonosaccharides, good statistics (bias, SEV, and R(2)) were obtained for the validation set, and no statistically (p = 0.05) significant differences were found between instrumental and polarimetric methods for these parameters. Statistical data for sucrose were not as good as those of the other parameters. Therefore, NIR spectroscopy is not an effective method for quantitative analysis of sucrose in these honey samples. However, NIR spectroscopy may be an acceptable method for semiquantitative evaluation of sucrose for honeys, such as those in our study, containing up to 3% of sucrose. Further work is necessary to validate the uncertainty at higher levels.

Optical monitoring of spinal cord subcellular damage after acute spinal cord injury

NASA Astrophysics Data System (ADS)

Shadgan, Babak; Manouchehri, Neda; So, Kitty; Shortt, Katelyn; Fong, Allan; Streijger, Femke; Macnab, Andrew; Kwon, Brian K.

2018-02-01

Introduction: Sudden physical trauma to the spinal cord results in acute spinal cord injury (SCI), leading to spinal cord (SC) tissue destruction, acute inflammation, increased SC intraparenchymal pressure, and tissue ischemia, hypoxia, and cellular necrosis. The ability to monitor SC tissue viability at subcellular level, using a real-time noninvasive method, would be extremely valuable to clinicians for estimating acute SCI damage, and adjusting and monitoring treatment in the intensive care setting. This study examined the feasibility and sensitivity of a custommade near infrared spectroscopy (NIRS) sensor to monitor the oxidation state of SC mitochondrial cytochrome aa3 (CCO), which reflects the subcellular damage of SC tissue in an animal model of SCI. Methods: Six anesthetized Yorkshire pigs were studied using a custom-made multi-wavelength NIRS system with a miniaturized optical sensor applied directly on the surgically exposed SC at T9. The oxidation states of SC tissue hemoglobin and CCO were monitored before, during and after acute SCI, and during mean arterial pressure alterations. Results: Non-invasive NIRS monitoring reflected changes in SC tissue CCO, simultaneous but independent of changes in hemoglobin saturation following acute SCI. A consistent decrease in SC tissue CCO chromophore concentration (-1.98 +/- 2.1 ab, p<0.05) was observed following SCI, indicating progressive SC cellular damage at the injury site. Elevation of mean arterial pressure can reduce SC tissue damage as suggested by different researchers and observed by significant increase in SC tissue CCO concentration (1.51 +/- 1.7 ab, p<0.05) in this study. Conclusions: This pilot study indicates that a novel miniaturized multi-wave NIRS sensor has the potential to monitor post-SCI changes of SC cytochrome aa3 oxygenation state in real time. Further development of this method may offer new options for improved SCI care.

VIS-NIR spectroscopy as a process analytical technology for compositional characterization of film biopolymers and correlation with their mechanical properties.

PubMed

Barbin, Douglas Fernandes; Valous, Nektarios A; Dias, Adriana Passos; Camisa, Jaqueline; Hirooka, Elisa Yoko; Yamashita, Fabio

2015-11-01

There is an increasing interest in the use of polysaccharides and proteins for the production of biodegradable films. Visible and near-infrared (VIS-NIR) spectroscopy is a reliable analytical tool for objective analyses of biological sample attributes. The objective is to investigate the potential of VIS-NIR spectroscopy as a process analytical technology for compositional characterization of biodegradable materials and correlation to their mechanical properties. Biofilms were produced by single-screw extrusion with different combinations of polybutylene adipate-co-terephthalate, whole oat flour, glycerol, magnesium stearate, and citric acid. Spectral data were recorded in the range of 400-2498nm at 2nm intervals. Partial least square regression was used to investigate the correlation between spectral information and mechanical properties. Results show that spectral information is influenced by the major constituent components, as they are clustered according to polybutylene adipate-co-terephthalate content. Results for regression models using the spectral information as predictor of tensile properties achieved satisfactory results, with coefficients of prediction (R(2)C) of 0.83, 0.88 and 0.92 (calibration models) for elongation, tensile strength, and Young's modulus, respectively. Results corroborate the correlation of NIR spectra with tensile properties, showing that NIR spectroscopy has potential as a rapid analytical technology for non-destructive assessment of the mechanical properties of the films. Copyright © 2015 Elsevier B.V. All rights reserved.

Study of Vis/NIR spectroscopy measurement on acidity of yogurt

NASA Astrophysics Data System (ADS)

He, Yong; Feng, Shuijuan; Wu, Di; Li, Xiaoli

2006-09-01

A fast measurement of pH of yogurt using Vis/NIR-spectroscopy techniques was established in order to measuring the acidity of yogurt rapidly. 27 samples selected separately from five different brands of yogurt were measured by Vis/NIR-spectroscopy. The pH of yogurt on positions scanned by spectrum was measured by a pH meter. The mathematical model between pH and Vis/NIR spectral measurements was established and developed based on partial least squares (PLS) by using Unscramble V9.2. Then 25 unknown samples from 5 different brands were predicted based on the mathematical model. The result shows that The correlation coefficient of pH based on PLS model is more than 0.890, and standard error of calibration (SEC) is 0.037, standard error of prediction (SEP) is 0.043. Through predicting the pH of 25 samples of yogurt from 5 different brands, the correlation coefficient between predictive value and measured value of those samples is more than 0918. The results show the good to excellent prediction performances. The Vis/NIR spectroscopy technique had a significant greater accuracy for determining the value of pH. It was concluded that the VisINIRS measurement technique can be used to measure pH of yogurt fast and accurately, and a new method for the measurement of pH of yogurt was established.

Near-infrared spectroscopy (NIRS) as a new tool for neuroeconomic research

PubMed Central

Kopton, Isabella M.; Kenning, Peter

2014-01-01

Over the last decade, the application of neuroscience to economic research has gained in importance and the number of neuroeconomic studies has grown extensively. The most common method for these investigations is fMRI. However, fMRI has limitations (particularly concerning situational factors) that should be countered with other methods. This review elaborates on the use of functional Near-Infrared Spectroscopy (fNIRS) as a new and promising tool for investigating economic decision making both in field experiments and outside the laboratory. We describe results of studies investigating the reliability of prototype NIRS studies, as well as detailing experiments using conventional and stationary fNIRS devices to analyze this potential. This review article shows that further research using mobile fNIRS for studies on economic decision making outside the laboratory could be a fruitful avenue helping to develop the potential of a new method for field experiments outside the laboratory. PMID:25147517

Application of the near-infrared spectroscopy in the pharmaceutical technology.

PubMed

Jamrógiewicz, Marzena

2012-07-01

Near-infrared (NIR) spectroscopy is currently the fastest-growing and the most versatile analytical method not only in the pharmaceutical sciences but also in the industry. This review focuses on recent NIR applications in the pharmaceutical technology. This article covers monitoring, by NIR, of many manufacturing processes, such as granulation, mixing or drying, in order to determine the end-point of these processes. In this paper, apart from basic theoretical information concerning the NIR spectra, there are included determinations of the quality and quantity of pharmaceutical compounds. Some examples of measurements and control of physicochemical parameters of the final medicinal products, such as hardness, porosity, thickness size, compression strength, disintegration time and potential counterfeit are included. Biotechnology and plant drug analysis using NIR is also described. Moreover, some disadvantages of this method are stressed and future perspectives are anticipated. Copyright © 2012 Elsevier B.V. All rights reserved.

A portable device for detecting fruit quality by diffuse reflectance Vis/NIR spectroscopy

NASA Astrophysics Data System (ADS)

Sun, Hongwei; Peng, Yankun; Li, Peng; Wang, Wenxiu

2017-05-01

Soluble solid content (SSC) is a major quality parameter to fruit, which has influence on its flavor or texture. Some researches on the on-line non-invasion detection of fruit quality were published. However, consumers desire portable devices currently. This study aimed to develop a portable device for accurate, real-time and nondestructive determination of quality factors of fruit based on diffuse reflectance Vis/NIR spectroscopy (520-950 nm). The hardware of the device consisted of four units: light source unit, spectral acquisition unit, central processing unit, display unit. Halogen lamp was chosen as light source. When working, its hand-held probe was in contact with the surface of fruit samples thus forming dark environment to shield the interferential light outside. Diffuse reflectance light was collected and measured by spectrometer (USB4000). ARM (Advanced RISC Machines), as central processing unit, controlled all parts in device and analyzed spectral data. Liquid Crystal Display (LCD) touch screen was used to interface with users. To validate its reliability and stability, 63 apples were tested in experiment, 47 of which were chosen as calibration set, while others as prediction set. Their SSC reference values were measured by refractometer. At the same time, samples' spectral data acquired by portable device were processed by standard normalized variables (SNV) and Savitzky-Golay filter (S-G) to eliminate the spectra noise. Then partial least squares regression (PLSR) was applied to build prediction models, and the best predictions results was achieved with correlation coefficient (r) of 0.855 and standard error of 0.6033° Brix. The results demonstrated that this device was feasible to quantitatively analyze soluble solid content of apple.

Antioxidant and photoprotective responses to elevated CO(2) and heat stress during holm oak regeneration by resprouting, evaluated with NIRS (near-infrared reflectance spectroscopy).

PubMed

Pintó-Marijuan, M; Joffre, R; Casals, I; De Agazio, M; Zacchini, M; García-Plazaola, J-I; Esteban, R; Aranda, X; Guàrdia, M; Fleck, I

2013-01-01

Photosynthetic, photoprotective and antioxidant responses during high temperature stress were determined in leaves of evergreen holm oak (Quercus ilex L.), the main species in Mediterranean forests, during resprouting under elevated CO(2) (750 μl·l(-1) ). Leaf chemicals, chloroplast pigments and non-enzymatic antioxidants were quantified in a single measurement using NIRS (near-infrared spectroscopy), a rapid and suitable method for ecophysiological purposes. Resprouts from plants grown under elevated CO(2) (RE) showed photosynthetic down-regulation, higher starch content and lower stomatal conductance, but similar stomatal density, than plants grown under current CO(2) concentrations (350 μl·l(-1) ) (RA). The photosynthetic sink reduction and need for more antioxidants and photoprotection in RE were reflected in an increased concentration of ascorbate (Asc) and phenolic compounds and in the contribution of the xanthophyll (Z/VAZ) and lutein epoxide cycles to excess energy dissipation as heat, and also reflected in chlorophyll fluorescence measurements. CO(2) assimilation parameters were stable from 25 to 35 °C in RE and RA, declining thereafter in RA in spite of a 2.3 °C lower leaf temperature. RE showed a more marked decline in photorespiration above 35 °C and less sensitive stomatal responses to high temperature stress than RA. During heat stress, RE had higher Asc, Z/VAZ and phenolics content, together with delayed enhancement of chloroplast lipophilic antioxidant compounds (carotenes and tocopherols). The high contribution of photoprotective systems and high temperature tolerance in resprouts developed under elevated CO(2) would mitigate the effect of photosynthesis acclimation during the regeneration of Q. ilex plants under climate change. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.

Near-Infrared Spatially Resolved Spectroscopy for Tablet Quality Determination.

PubMed

Igne, Benoît; Talwar, Sameer; Feng, Hanzhou; Drennen, James K; Anderson, Carl A

2015-12-01

Near-infrared (NIR) spectroscopy has become a well-established tool for the characterization of solid oral dosage forms manufacturing processes and finished products. In this work, the utility of a traditional single-point NIR measurement was compared with that of a spatially resolved spectroscopic (SRS) measurement for the determination of tablet assay. Experimental designs were used to create samples that allowed for calibration models to be developed and tested on both instruments. Samples possessing a poor distribution of ingredients (highly heterogeneous) were prepared by under-blending constituents prior to compaction to compare the analytical capabilities of the two NIR methods. The results indicate that SRS can provide spatial information that is usually obtainable only through imaging experiments for the determination of local heterogeneity and detection of abnormal tablets that would not be detected with single-point spectroscopy, thus complementing traditional NIR measurement systems for in-line, and in real-time tablet analysis. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

A "NIRS" death experience: a reduction in cortical oxygenation by time-resolved near-infrared spectroscopy preceding cardiac arrest.

PubMed

Lanks, C; Kim, C B; Rossiter, H B

2017-09-08

Near-infrared spectroscopy (NIRS) has been used effectively post-cardiac-arrest to gauge adequacy of resuscitation and predict the likelihood of achieving a return of spontaneous circulation. However, preempting hemodynamic collapse is preferable to achieving ROSC through advanced cardiac life support. Minimizing "time down" without end-organ perfusion has always been a central pillar of ACLS. In many critically ill patients there is a prolonged phase of end-organ hypoperfusion preceding loss of palpable pulses and initiation of ACLS. Due to the relative infrequency of in-hospital cardiac arrest, NIRS has not previously evaluated the period immediately prior to hemodynamic collapse. Here we report a young man who suffered a pulseless electrical activity (PEA) arrest while cortical oxygenation was monitored using time-resolved near-infrared spectroscopy. The onset of cortical deoxygenation preceded the loss of palpable pulses by 15 min, suggesting that TRS-NIRS monitoring might provide a means of preempting PEA arrest. Our experience with this patient represents a promising new direction for continuous NIRS monitoring and has the potential to not only predict clinical outcomes, but affect them to the patient's benefit as well.

NIR analysis of cellulose and lactose--application to ecstasy tablet analysis.

PubMed

Baer, Ines; Gurny, Robert; Margot, Pierre

2007-04-11

Cellulose and lactose are the most frequently used excipients in illicit ecstasy production. The aim of this project was to use near infrared reflectance spectroscopy (NIRS) for the determination of the different chemical forms of these two substances, as well as for the differentiation of their origin (producer). It was possible to distinguish between the different chemical forms of both compounds, as well as between their origins (producers), although within limits. Furthermore, the possibilities to apply NIR for the analysis of substances such as found in illicit tablets were studied. First, a few cellulose and lactose samples were chosen to make mixtures with amphetamine at three degrees of purity (5, 10 and 15%), in order to study the resulting changes in the spectra as well as to simultaneously quantify amphetamine and identify the excipient. A PLS2 model could be build to predict concentrations and excipient. Secondarily, the technique was to be applied to real ecstasy tablets. About 40 ecstasy seizures were analysed with the aim to determine the excipient and to check them against each other. Identification of the excipients was not always obvious, especially when more than one excipient were present. However, a comparison between tablets appeared to give groups of similar samples. NIR analysis results in spectra representing the tablet blend as a whole taking into account all absorbing compounds. Although NIRS seems to be an appropriate method for ecstasy profiling, little is known about intra- and intervariability of compression batches.

Comparison of NIR and FT-IR spectral models in the prediction of cotton fiber strength

USDA-ARS?s Scientific Manuscript database

Strength quality in cotton fibers is one of several important end-use characteristics. In routine programs, it has been mostly assessed by automation-oriented high volume instrument (HVI) system. An alternative method for cotton strength is near infrared (NIR) spectroscopy. Although previous NIR mod...

Cotton micronaire measurements by small portable near infrared (nir) analyzers

USDA-ARS?s Scientific Manuscript database

A key quality and processing parameter for cotton fiber is micronaire, which is a function of the fiber’s maturity and fineness. Near Infrared (NIR) spectroscopy has previously shown the ability to measure micronaire, primarily in the laboratory and using large, research-grade laboratory NIR instru...

Classification of change detection and change blindness from near-infrared spectroscopy signals

NASA Astrophysics Data System (ADS)

Tanaka, Hirokazu; Katura, Takusige

2011-08-01

Using a machine-learning classification algorithm applied to near-infrared spectroscopy (NIRS) signals, we classify a success (change detection) or a failure (change blindness) in detecting visual changes for a change-detection task. Five subjects perform a change-detection task, and their brain activities are continuously monitored. A support-vector-machine algorithm is applied to classify the change-detection and change-blindness trials, and correct classification probability of 70-90% is obtained for four subjects. Two types of temporal shapes in classification probabilities are found: one exhibiting a maximum value after the task is completed (postdictive type), and another exhibiting a maximum value during the task (predictive type). As for the postdictive type, the classification probability begins to increase immediately after the task completion and reaches its maximum in about the time scale of neuronal hemodynamic response, reflecting a subjective report of change detection. As for the predictive type, the classification probability shows an increase at the task initiation and is maximal while subjects are performing the task, predicting the task performance in detecting a change. We conclude that decoding change detection and change blindness from NIRS signal is possible and argue some future applications toward brain-machine interfaces.

Near-infrared spectroscopic assessment of oxygen delivery to free flaps on monkeys following vascular occlusions and inhalation of pure oxygen

NASA Astrophysics Data System (ADS)

Tian, Fenghua; Ding, Haishu; Cai, Zhigang; Wang, Guangzhi; Zhao, Fuyun

2002-04-01

In recent studies, near-infrared spectroscopy (NIRS) has been considered as a potentially ideal noninvasive technique for the postoperative monitoring of plastic surgery. In this study, free flaps were raised on rhesus monkeys' forearms and oxygen delivery to these flaps was monitored following vascular occlusions and inhalation of pure oxygen. Optical fibers were adopted in the probe of the oximeter so that the detection could be performed in reflectance mode. The distance between emitter and detector can be adjusted easily to achieve the best efficacy. Different and repeatable patterns of changes were measured following vascular occlusions (arterial occlusion, venous occlusion and total occlusion) on flaps. It is clear that the near-infrared spectroscopy is capable of postoperatively monitoring vascular problems in flaps. NIRS showed high sensitivity to detect the dynamic changes in flaps induced by inhalation of pure oxygen in this study. The experimental results indicated that it was potential to assess tissue viability utilizing the dynamic changes induced by a noninvasive stimulation. It may be a new assessing method that is rapid, little influenced by other factors and brings less discomfort to patients.

[Rapid determination of componential contents and calorific value of selected agricultural biomass feedstocks using spectroscopic technology].

PubMed

Sheng, Kui-Chuan; Shen, Ying-Ying; Yang, Hai-Qing; Wang, Wen-Jin; Luo, Wei-Qiang

2012-10-01

Rapid determination of biomass feedstock properties is of value for the production of biomass densification briquetting fuel with high quality. In the present study, visible and near-infrared (Vis-NIR) spectroscopy was employed to build prediction models of componential contents, i. e. moisture, ash, volatile matter and fixed-carbon, and calorific value of three selected species of agricultural biomass feedstock, i. e. pine wood, cedar wood, and cotton stalk. The partial least squares (PLS) cross validation results showed that compared with original reflection spectra, PLS regression models developed for first derivative spectra produced higher prediction accuracy with coefficients of determination (R2) of 0.97, 0.94 and 0.90, and residual prediction deviation (RPD) of 6.57, 4.00 and 3.01 for ash, volatile matter and moisture, respectively. Good prediction accuracy was achieved with R2 of 0.85 and RPD of 2.55 for fixed carbon, and R2 of 0.87 and RPD of 2.73 for calorific value. It is concluded that the Vis-NIR spectroscopy is promising as an alternative of traditional proximate analysis for rapid determination of componential contents and calorific value of agricultural biomass feedstock

Utilizing functional near-infrared spectroscopy for prediction of cognitive workload in noisy work environments.

PubMed

Gabbard, Ryan; Fendley, Mary; Dar, Irfaan A; Warren, Rik; Kashou, Nasser H

2017-10-01

Occupational noise frequently occurs in the work environment in military intelligence, surveillance, and reconnaissance operations. This impacts cognitive performance by acting as a stressor, potentially interfering with the analysts' decision-making process. We investigated the effects of different noise stimuli on analysts' performance and workload in anomaly detection by simulating a noisy work environment. We utilized functional near-infrared spectroscopy (fNIRS) to quantify oxy-hemoglobin (HbO) and deoxy-hemoglobin concentration changes in the prefrontal cortex (PFC), as well as behavioral measures, which include eye tracking, reaction time, and accuracy rate. We hypothesized that noisy environments would have a negative effect on the participant in terms of anomaly detection performance due to the increase in workload, which would be reflected by an increase in PFC activity. We found that HbO for some of the channels analyzed were significantly different across noise types ([Formula: see text]). Our results also indicated that HbO activation for short-intermittent noise stimuli was greater in the PFC compared to long-intermittent noises. These approaches using fNIRS in conjunction with an understanding of the impact on human analysts in anomaly detection could potentially lead to better performance by optimizing work environments.

Influence of earlobe thickness on near infrared spectroscopy

NASA Astrophysics Data System (ADS)

Jiang, Jingying; Wang, Tianpei; Li, Si; Li, Lin; Liu, Jiajia; Xu, Kexin

2017-03-01

Near-infrared spectroscopy has been recognized as a potential technology for noninvasive blood glucose sensing. However, the detected spectral signal is unstable mainly because of (1) the weak light absorption of glucose itself within NIR range, (2) the influence of temperature and individual differences of biotissue. Our previous results demonstrated that the synergistic effect of both transmittance and reflectance could enhance the strength of the detection signal. In this talk, we design a set of experiments to analyze the effect of earlobe thickness on Near Infrared spectroscopic measurement by using home-made optical fiber probe within the wavelength of 1000-1600nm. Firstly, we made a MC simulation of single-layer skin model and five-layer skin model to get the diffused transmittance spectra and diffused reflectance spectra under different optaical path lengths. And then we obtain the spectra of the earlobes from different volunteers by the same way. The experimental results showed that with the increase of the thickness,the light intensity of diffused transmittance decreases, and the light intensity of diffused reflectance remaines substantially unchanged.

Near infrared spectroscopic imaging assessment of cartilage composition: Validation with mid infrared imaging spectroscopy.

PubMed

Palukuru, Uday P; Hanifi, Arash; McGoverin, Cushla M; Devlin, Sean; Lelkes, Peter I; Pleshko, Nancy

2016-07-05

Disease or injury to articular cartilage results in loss of extracellular matrix components which can lead to the development of osteoarthritis (OA). To better understand the process of disease development, there is a need for evaluation of changes in cartilage composition without the requirement of extensive sample preparation. Near infrared (NIR) spectroscopy is a chemical investigative technique based on molecular vibrations that is increasingly used as an assessment tool for studying cartilage composition. However, the assignment of specific molecular vibrations to absorbance bands in the NIR spectrum of cartilage, which arise from overtones and combinations of primary absorbances in the mid infrared (MIR) spectral region, has been challenging. In contrast, MIR spectroscopic assessment of cartilage is well-established, with many studies validating the assignment of specific bands present in MIR spectra to specific molecular vibrations. In the current study, NIR imaging spectroscopic data were obtained for compositional analysis of tissues that served as an in vitro model of OA. MIR spectroscopic data obtained from the identical tissue regions were used as the gold-standard for collagen and proteoglycan (PG) content. MIR spectroscopy in transmittance mode typically requires a much shorter pathlength through the sample (≤10 microns thick) compared to NIR spectroscopy (millimeters). Thus, this study first addressed the linearity of small absorbance bands in the MIR region with increasing tissue thickness, suitable for obtaining a signal in both the MIR and NIR regions. It was found that the linearity of specific, small MIR absorbance bands attributable to the collagen and PG components of cartilage (at 1336 and 856 cm(-1), respectively) are maintained through a thickness of 60 μm, which was also suitable for NIR data collection. MIR and NIR spectral data were then collected from 60 μm thick samples of cartilage degraded with chondroitinase ABC as a model of OA. Partial least squares (PLS) regression using NIR spectra as input predicted the MIR-determined compositional parameters of PG/collagen within 6% of actual values. These results indicate that NIR spectral data can be used to assess molecular changes that occur with cartilage degradation, and further, the data provide a foundation for future clinical studies where NIR fiber optic probes can be used to assess the progression of cartilage degradation. Copyright © 2016 Elsevier B.V. All rights reserved.

Ability of near infrared spectroscopy to monitor air-dry density distribution and variation of wood

Treesearch

Brian K. Via; Chi-Leung So; Todd F. Shupe; Michael Stine; Leslie H. Groom

2005-01-01

Process control of wood density with near infrared spectroscopy (NIR) would be useful for pulp mills that need to maximize pulp yield without compromising paper strength properties. If models developed from the absorbance at wavelengths in the NIR region could provide density histograms, fiber supply personnel could monitor chip density variation as the chips enter the...

High-throughput quantitative biochemical characterization of algal biomass by NIR spectroscopy; multiple linear regression and multivariate linear regression analysis.

PubMed

Laurens, L M L; Wolfrum, E J

2013-12-18

One of the challenges associated with microalgal biomass characterization and the comparison of microalgal strains and conversion processes is the rapid determination of the composition of algae. We have developed and applied a high-throughput screening technology based on near-infrared (NIR) spectroscopy for the rapid and accurate determination of algal biomass composition. We show that NIR spectroscopy can accurately predict the full composition using multivariate linear regression analysis of varying lipid, protein, and carbohydrate content of algal biomass samples from three strains. We also demonstrate a high quality of predictions of an independent validation set. A high-throughput 96-well configuration for spectroscopy gives equally good prediction relative to a ring-cup configuration, and thus, spectra can be obtained from as little as 10-20 mg of material. We found that lipids exhibit a dominant, distinct, and unique fingerprint in the NIR spectrum that allows for the use of single and multiple linear regression of respective wavelengths for the prediction of the biomass lipid content. This is not the case for carbohydrate and protein content, and thus, the use of multivariate statistical modeling approaches remains necessary.

Applications of NIR spectroscopy to monitoring and analyzing the solid state during industrial crystallization processes.

PubMed

Févotte, G; Calas, J; Puel, F; Hoff, C

2004-04-01

Fiber-optic near infrared (NIR) spectroscopy was used to investigate several key features of the polymorphic transitions observed during the crystallization and the filtration of SaC, an Active Pharmaceutical Ingredient (API) produced by Sanofi-Synthelabo. Using few samples, the spectroscopic data were calibrated to provide measurements of the polymorphic composition of the solid product which is likely to appear in two crystalline forms or in the amorphous state. Both qualitative and quantitative methods were successfully evaluated to characterize the API. The NIR spectroscopy measurement was then applied to investigate the kinetic behavior of the phase transition phenomena against various operating conditions. From the viewpoint of industrial process development several applications are presented. The effects of temperature and seed crystal habits on the rate of transition of filtration cakes are briefly investigated; and a study of the effect of residual water in the solvent on the transition occurring during filtration is more deeply analyzed. The experimental results demonstrate that highly valuable information can be provided by the NIR spectroscopy measurements, when one aims at understanding more deeply and optimizing the consequences of various and complex phenomena involved during the solid processing chain.

Near infra red spectroscopy as a multivariate process analytical tool for predicting pharmaceutical co-crystal concentration.

PubMed

Wood, Clive; Alwati, Abdolati; Halsey, Sheelagh; Gough, Tim; Brown, Elaine; Kelly, Adrian; Paradkar, Anant

2016-09-10

The use of near infra red spectroscopy to predict the concentration of two pharmaceutical co-crystals; 1:1 ibuprofen-nicotinamide (IBU-NIC) and 1:1 carbamazepine-nicotinamide (CBZ-NIC) has been evaluated. A partial least squares (PLS) regression model was developed for both co-crystal pairs using sets of standard samples to create calibration and validation data sets with which to build and validate the models. Parameters such as the root mean square error of calibration (RMSEC), root mean square error of prediction (RMSEP) and correlation coefficient were used to assess the accuracy and linearity of the models. Accurate PLS regression models were created for both co-crystal pairs which can be used to predict the co-crystal concentration in a powder mixture of the co-crystal and the active pharmaceutical ingredient (API). The IBU-NIC model had smaller errors than the CBZ-NIC model, possibly due to the complex CBZ-NIC spectra which could reflect the different arrangement of hydrogen bonding associated with the co-crystal compared to the IBU-NIC co-crystal. These results suggest that NIR spectroscopy can be used as a PAT tool during a variety of pharmaceutical co-crystal manufacturing methods and the presented data will facilitate future offline and in-line NIR studies involving pharmaceutical co-crystals. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Flavonoid and Antioxidant Capacity of Propolis Prediction Using Near Infrared Spectroscopy.

PubMed

Betances-Salcedo, Eddy; Revilla, Isabel; Vivar-Quintana, Ana M; González-Martín, M Inmaculada

2017-07-18

The use of propolis as a dietary supplement or as an ingredient in different food products is increasing, due to its antioxidant and bactericidal properties. These nutritional properties directly depend on its phenolic composition. For this reason, this study analysed the total contents of flavones and flavonols, flavanones and dihydroflavonols, and the antioxidant capacity by using the methods of ABTS and linoleic acid/ β -carotene in 99 samples of propolis from Spain and Chile. A rapid method was developed for quantifying these parameters in raw propolis using near infrared (NIR) spectroscopy with a remote reflectance fibre-optic probe applied directly to the ground-up sample. The models developed allow for the determination of the total flavones and flavonols (0-183 mg quercetin/g propolis and 0-72 mg rutin/g propolis), of the total flavanones and dihydroflavonols (9-109 mg pinocembrin/g propolis extract), and of its antioxidant capacity by the ABTS method based on the reduction of the 2.2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation(0-3212.6 nmol Trolox/mg of propolis) and of linoleic acid/ β -carotene (22-86% inhibition). The NIR spectroscopy models were applied in external validation to different samples of the calibration group, which led to the conclusion that the methods developed provide significantly identical data to the initial chemical data of reference.

Fast gas spectroscopy using pulsed quantum cascade lasers

NASA Astrophysics Data System (ADS)

Beyer, T.; Braun, M.; Lambrecht, A.

2003-03-01

Laser spectroscopy has found many industrial applications, e.g., control of automotive exhaust and process monitoring. The midinfrared region is of special interest because it has stronger absorption lines compared to the near infrared (NIR). However, in the NIR high quality reliable laser sources, detectors, and passive optical components are available. A quantum cascade laser could change this situation if fundamental advantages can be exploited with compact and reliable systems. It will be shown that, using pulsed lasers and available fast detectors, lower residual sensitivity levels than in corresponding NIR systems can be achieved. The stability is sufficient for industrial applications.

Spectral relationships for atmospheric correction. I. Validation of red and near infra-red marine reflectance relationships.

PubMed

Goyens, C; Jamet, C; Ruddick, K G

2013-09-09

The present study provides an extensive overview of red and near infra-red (NIR) spectral relationships found in the literature and used to constrain red or NIR-modeling schemes in current atmospheric correction (AC) algorithms with the aim to improve water-leaving reflectance retrievals, ρw(λ), in turbid waters. However, most of these spectral relationships have been developed with restricted datasets and, subsequently, may not be globally valid, explaining the need of an accurate validation exercise. Spectral relationships are validated here with turbid in situ data for ρw(λ). Functions estimating ρw(λ) in the red were only valid for moderately turbid waters (ρw(λNIR) < 3.10(-3)). In contrast, bounding equations used to limit ρw(667) retrievals according to the water signal at 555 nm, appeared to be valid for all turbidity ranges presented in the in situ dataset. In the NIR region of the spectrum, the constant NIR reflectance ratio suggested by Ruddick et al. (2006) (Limnol. Oceanogr. 51, 1167-1179), was valid for moderately to very turbid waters (ρw(λNIR) < 10(-2)) while the polynomial function, initially developed by Wang et al. (2012) (Opt. Express 20, 741-753) with remote sensing reflectances over the Western Pacific, was also valid for extremely turbid waters (ρw(λNIR) > 10(-2)). The results of this study suggest to use the red bounding equations and the polynomial NIR function to constrain red or NIR-modeling schemes in AC processes with the aim to improve ρw(λ) retrievals where current AC algorithms fail.

The changes of cerebral hemodynamics during ketamine induced anesthesia in a rat model.

PubMed

Bae, Jayyoung; Shin, Teo J; Kim, Seonghyun; Choi, Dong-Hyuk; Cho, Dongrae; Ham, Jinsil; Manca, Marco; Jeong, Seongwook; Lee, Boreom; Kim, Jae G

2018-05-25

Current electroencephalogram (EEG) based-consciousness monitoring technique is vulnerable to specific clinical conditions (eg, epilepsy and dementia). However, hemodynamics is the most fundamental and well-preserved parameter to evaluate, even under severe clinical situations. In this study, we applied near-infrared spectroscopy (NIRS) system to monitor hemodynamic change during ketamine-induced anesthesia to find its correlation with the level of consciousness. Oxy-hemoglobin (OHb) and deoxy-hemoglobin concentration levels were continuously acquired throughout the experiment, and the reflectance ratio between 730 and 850 nm was calculated to quantify the hemodynamic changes. The results showed double peaks of OHb concentration change during ketamine anesthesia, which seems to be closely related to the consciousness state of the rat. This finding suggests the possibility of NIRS based-hemodynamic monitoring as a supplementary parameter for consciousness monitoring, compensating drawbacks of EEG signal based monitoring. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Adaptable Near-Infrared Spectroscopy Fiber Array for Improved Coupling to Different Breast Sizes During Clinical MRI

PubMed Central

Mastanduno, Michael A.; El-Ghussein, Fadi; Jiang, Shudong; DiFlorio-Alexander, Roberta; Junqing, Xu; Hong, Yin; Pogue, Brian W.; Paulsen, Keith D.

2016-01-01

Rationale and Objectives Near-infrared spectroscopy (NIRS) of breast can provide functional information on the vascular and structural compartments of tissues in regions identified during simultaneous magnetic resonance imaging (MRI). NIRS can be acquired during dynamic contrast-enhanced MRI (DCE-MRI) to accomplish image-guided spectroscopy of the enhancing regions, potentially increasing the diagnostic specificity of the examination and reducing the number of biopsies performed as a result of inconclusive MRI breast imaging studies. Materials and Methods We combine synergistic attributes of concurrent DCE-MRI and NIRS with a new design of the clinical NIRS breast interface that couples to a standard MR breast coil and allows imaging of variable breast sizes. Spectral information from healthy volunteers and cancer patients is recovered, providing molecular information in regions defined by the segmented MR image volume. Results The new coupling system significantly improves examination utility by allowing improved coupling of the NIR fibers to breasts of all cup sizes and lesion locations. This improvement is demonstrated over a range of breast sizes (cup size A through D) and normal tissue heterogeneity using a group of eight healthy volunteers and two cancer patients. Lesions located in the axillary region and medial-posterior breast are now accessible to NIRS optodes. Reconstructed images were found to have biologically plausible hemoglobin content, oxygen saturation, and water and lipid fractions. Conclusions In summary, a new NIRS/MRI breast interface was developed to accommodate the variation in breast sizes and lesion locations that can be expected in clinical practice. DCE-MRI–guided NIRS quantifies total hemoglobin, oxygenation, and scattering in MR-enhancing regions, increasing the diagnostic information acquired from MR examinations. PMID:24439327

Dynamic topographical pattern classification of multichannel prefrontal NIRS signals: II. Online differentiation of mental arithmetic and rest

NASA Astrophysics Data System (ADS)

Schudlo, Larissa C.; Chau, Tom

2014-02-01

Objective. Near-infrared spectroscopy (NIRS) has recently gained attention as a modality for brain-computer interfaces (BCIs), which may serve as an alternative access pathway for individuals with severe motor impairments. For NIRS-BCIs to be used as a real communication pathway, reliable online operation must be achieved. Yet, only a limited number of studies have been conducted online to date. These few studies were carried out under a synchronous paradigm and did not accommodate an unconstrained resting state, precluding their practical clinical implication. Furthermore, the potentially discriminative power of spatiotemporal characteristics of activation has yet to be considered in an online NIRS system. Approach. In this study, we developed and evaluated an online system-paced NIRS-BCI which was driven by a mental arithmetic activation task and accommodated an unconstrained rest state. With a dual-wavelength, frequency domain near-infrared spectrometer, measurements were acquired over nine sites of the prefrontal cortex, while ten able-bodied participants selected letters from an on-screen scanning keyboard via intentionally controlled brain activity (using mental arithmetic). Participants were provided dynamic NIR topograms as continuous visual feedback of their brain activity as well as binary feedback of the BCI's decision (i.e. if the letter was selected or not). To classify the hemodynamic activity, temporal features extracted from the NIRS signals and spatiotemporal features extracted from the dynamic NIR topograms were used in a majority vote combination of multiple linear classifiers. Main results. An overall online classification accuracy of 77.4 ± 10.5% was achieved across all participants. The binary feedback was found to be very useful during BCI use, while not all participants found value in the continuous feedback provided. Significance. These results demonstrate that mental arithmetic is a potent mental task for driving an online system-paced NIRS-BCI. BCI feedback that reflects the classifier's decision has the potential to improve user performance. The proposed system can provide a framework for future online NIRS-BCI development and testing.

Multispectral near-infrared reflectance and transillumination imaging of occlusal carious lesions: variations in lesion contrast with lesion depth

NASA Astrophysics Data System (ADS)

Simon, Jacob C.; Curtis, Donald A.; Darling, Cynthia L.; Fried, Daniel

2018-02-01

In vivo and in vitro studies have demonstrated that near-infrared (NIR) light at λ=1300-1700-nm can be used to acquire high contrast images of enamel demineralization without interference of stains. The objective of this study was to determine if a relationship exists between the NIR image contrast of occlusal lesions and the depth of the lesion. Extracted teeth with varying amounts of natural occlusal decay were measured using a multispectral-multimodal NIR imaging system which captures λ=1300-nm occlusal transillumination, and λ=1500-1700-nm cross-polarized reflectance images. Image analysis software was used to calculate the lesion contrast detected in both images from matched positions of each imaging modality. Samples were serially sectioned across the lesion with a precision saw, and polarized light microscopy was used to measure the respective lesion depth relative to the dentinoenamel junction. Lesion contrast measured from NIR crosspolarized reflectance images positively correlated (p<0.05) with increasing lesion depth and a statistically significant difference between inner enamel and dentin lesions was observed. The lateral width of pit and fissures lesions measured in both NIR cross-polarized reflectance and NIR transillumination positively correlated with lesion depth.

[A review on studies and applications of near infrared spectroscopy technique(NIRS) in detecting quality of hay].

PubMed

Ding, Wu-Rong; Gan, You-Min; Guo, Xu-Sheng; Yang, Fu-Yu

2009-02-01

The quality of hay can directly affect the price of hay and also livestock productivity. Many kinds of methods have been developed for detecting the quality of hay and the method of near infrared spectroscopy (NIRS) has been widely used with consideration of its fast, effective and nondestructive characteristics during detecting process. In the present paper, the feasibility and effectiveness of application of NIRS to detecting hay quality were expounded. Meanwhile, the advance in the study of using NIRS to detect chemical compositions, extent of incursion by epiphyte, amount of toxicant excreted by endogenetic epiphyte and some minim components that can not be detected by using chemical methods were also introduced detailedly. Based on the review of the progresses in using NIRS to detect the quality of hay, it can be concluded that using NIRS to detect hay quality can avoid the disadvantages of time wasting, complication and high cost when using traditional chemical method. And for better utilization of NIRS in practice, some more studies still need to be implemented to further perfect and improve the utilization of NIRS for detecting forage quality, and more accurate modes and systematic analysis software need to be established in times to come.

Accelerometer-based method for correcting signal baseline changes caused by motion artifacts in medical near-infrared spectroscopy

NASA Astrophysics Data System (ADS)

Virtanen, Jaakko; Noponen, Tommi; Kotilahti, Kalle; Virtanen, Juha; Ilmoniemi, Risto J.

2011-08-01

In medical near-infrared spectroscopy (NIRS), movements of the subject often cause large step changes in the baselines of the measured light attenuation signals. This prevents comparison of hemoglobin concentration levels before and after movement. We present an accelerometer-based motion artifact removal (ABAMAR) algorithm for correcting such baseline motion artifacts (BMAs). ABAMAR can be easily adapted to various long-term monitoring applications of NIRS. We applied ABAMAR to NIRS data collected in 23 all-night sleep measurements and containing BMAs from involuntary movements during sleep. For reference, three NIRS researchers independently identified BMAs from the data. To determine whether the use of an accelerometer improves BMA detection accuracy, we compared ABAMAR to motion detection based on peaks in the moving standard deviation (SD) of NIRS data. The number of BMAs identified by ABAMAR was similar to the number detected by the humans, and 79% of the artifacts identified by ABAMAR were confirmed by at least two humans. While the moving SD of NIRS data could also be used for motion detection, on average 2 out of the 10 largest SD peaks in NIRS data each night occurred without the presence of movement. Thus, using an accelerometer improves BMA detection accuracy in NIRS.

Structural and Visible-Near Infrared Optical Properties of Cr-Doped TiO2 for Colored Cool Pigments

NASA Astrophysics Data System (ADS)

Yuan, Le; Weng, Xiaolong; Zhou, Ming; Zhang, Qingyong; Deng, Longjiang

2017-11-01

Chromium-doped TiO2 pigments were synthesized via a solid-state reaction method and studied with X-ray diffraction, SEM, XPS, and UV-VIS-NIR reflectance spectroscopy. The incorporation of Cr3+ accelerates the transition from the anatase phase to the rutile phase and compresses the crystal lattice. Moreover, the particle morphology, energy gap, and reflectance spectrum of Cr-doped TiO2 pigments is affected by the crystal structure and doping concentration. For the rutile samples, some of the Cr3+ ions are oxidized to Cr4+ after sintering at a high temperature, which leads to a strong near-infrared absorption band due to the 3A2 → 3 T1 electric dipole-allowed transitions of Cr4+. And the decrease of the band gap causes an obvious redshift of the optical absorption edges as the doping concentration increases. Thus, the VIS and near-infrared average reflectance of the rutile Ti1 - x Cr x O2 sample decrease by 60.2 and 58%, respectively, when the Cr content increases to x = 0.0375. Meanwhile, the color changes to black brown. However, for the anatase Ti1 - x Cr x O2 pigments, only the VIS reflection spectrum is inhibited by forming some characteristic visible light absorption peaks of Cr3+. The morphology, band gap, and NIR reflectance are not significantly affected. Finally, a Cr-doped anatase TiO2 pigment with a brownish-yellow color and 90% near-infrared reflectance can be obtained.

Separation of the global and local components in functional near-infrared spectroscopy signals using principal component spatial filtering

PubMed Central

Zhang, Xian; Noah, Jack Adam; Hirsch, Joy

2016-01-01

Abstract. Global systemic effects not specific to a task can be prominent in functional near-infrared spectroscopy (fNIRS) signals and the separation of task-specific fNIRS signals and global nonspecific effects is challenging due to waveform correlations. We describe a principal component spatial filter algorithm for separation of the global and local effects. The effectiveness of the approach is demonstrated using fNIRS signals acquired during a right finger-thumb tapping task where the response patterns are well established. Both the temporal waveforms and the spatial pattern consistencies between oxyhemoglobin and deoxyhemoglobin signals are significantly improved, consistent with the basic physiological basis of fNIRS signals and the expected pattern of activity associated with the task. PMID:26866047

Near-infrared Spectroscopy in the Brewing Industry.

PubMed

Sileoni, Valeria; Marconi, Ombretta; Perretti, Giuseppe

2015-01-01

This article offers an exhaustive description of the use of Near-Infrared (NIR) Spectroscopy in the brewing industry. This technique is widely used for quality control testing of raw materials, intermediates, and finished products, as well as process monitoring during malting and brewing. In particular, most of the reviewed works focus on the assessment of barley properties, aimed at quickly selecting the best barley varieties in order to produce a high-quality malt leading to high-quality beer. Various works concerning the use of NIR in the evaluation of raw materials, such as barley, malt, hop, and yeast, are also summarized here. The implementation of NIR sensors for the control of malting and brewing processes is also highlighted, as well as the use of NIR for quality assessment of the final product.

A fiber optic probe coupled low-cost CMOS-camera-based system for simultaneous measurement of oxy-, deoxyhemoglobin, and blood flow

NASA Astrophysics Data System (ADS)

Seong, Myeongsu; Phillips, Zephaniah; Mai, Phuong M.; Yeo, Chaebeom; Song, Cheol; Lee, Kijoon; Kim, Jae G.

2015-07-01

Appropriate oxygen supply and blood flow are important in coordination of body functions and maintaining a life. To measure both oxygen supply and blood flow simultaneously, we developed a system that combined near-infrared spectroscopy (NIRS) and diffuse speckle contrast analysis (DSCA). Our system is more cost effective and compact than such combined systems as diffuse correlation spectroscopy(DCS)-NIRS or DCS flow oximeter, and also offers the same quantitative information. In this article, we present the configuration of DSCA-NIRS and preliminary data from an arm cuff occlusion and a repeated gripping exercise. With further investigation, we believe that DSCA-NIRS can be a useful tool for the field of neuroscience, muscle physiology and metabolic diseases such as diabetes.

Genesis and properties of wetland soils by VIS-NIR-SWIR as a technique for environmental monitoring.

PubMed

Demattê, José Alexandre Melo; Horák-Terra, Ingrid; Beirigo, Raphael Moreira; Terra, Fabrício da Silva; Marques, Karina Patrícia Prazeres; Fongaro, Caio Troula; Silva, Alexandre Christófaro; Vidal-Torrado, Pablo

2017-07-15

Wetlands are important ecosystems characterized by redoximorphic environments producing typical soil forming processes and organic carbon accumulation. Assessments and management of these areas are dependent on knowledge about soil characteristics and variability. By reflectance spectroscopy, information about soils can be obtained since their spectral behaviors are directly related to their chemical, physical, and mineralogical properties reflecting the pedogenetic processes and environment conditions. Our aims were: (a) to characterize the main soil classes of wetlands regarding their spectral behaviors in VIS-NIR-SWIR (350-2500 nm) and relate them to pedogenesis and environmental conditions, (b) to determine spectral ranges (bands) with greater expression of the main soil properties, (c) to identify spectral variations and similarities between hydromorphic soils from wetlands and other soils under different moisture conditions, and (d) to propose spectral models to quantify some chemical and physical soil properties used as environmental quality indicators. Nine soil profiles from the Pantanal region (Mato Grosso State, Brazil) and one from the Serra do Espinhaço Meridional (Minas Gerais State, Brazil) were investigated. Spectral morphology interpretation allowed identifying horizon differences regarding shape, absorption features and reflectance intensity. Some pedogenetic processes of wetland soils related to organic carbon accumulation and oxide iron variation were identified by spectra. Principal Component Analysis allowed discriminating soils from wetland and outside this area (oxidic environment). Quantification of organic carbon was possible with R 2 of 0.90 and low error. Quantification of clay content was masked by soils with organic carbon content over 2% where it was not possible to quantify with high R 2 and low error both properties when dataset has soil samples with high organic carbon content. By reflectance spectroscopy, important characteristics of wetland soils can be identified and used to distinguish from soils of different environments at low costs, reduced time, and with environmental quality. Copyright © 2017 Elsevier Ltd. All rights reserved.

Near-infrared spectroscopy (NIRS) as a tool to monitor exhaust air from poultry operations.

PubMed

Druckenmüller, Katharina; Günther, Klaus; Elbers, Gereon

2018-07-15

Intensive poultry operation systems emit a considerable volume of inorganic and organic matter in the surrounding environment. Monitoring cleaning properties of exhaust air cleaning systems and to detect small but significant changes in emission characteristics during a fattening cycle is important for both emission and fattening process control. In the present study, we evaluated the potential of near-infrared spectroscopy (NIRS) combined with chemometric techniques as a monitoring tool of exhaust air from poultry operation systems. To generate a high-quality data set for evaluation, the exhaust air of two poultry houses was sampled by applying state-of-the-art filter sampling protocols. The two stables were identical except for one crucial difference, the presence or absence of an exhaust air cleaning system. In total, twenty-one exhaust air samples were collected at the two sites to monitor spectral differences caused by the cleaning device, and to follow changes in exhaust air characteristics during a fattening period. The total dust load was analyzed by gravimetric determination and included as a response variable in multivariate data analysis. The filter samples were directly measured with NIR spectroscopy. Principal component analysis (PCA), linear discriminant analysis (LDA), and factor analysis (FA) were effective in classifying the NIR exhaust air spectra according to fattening day and origin. The results indicate that the dust load and the composition of exhaust air (inorganic or organic matter) substantially influence the NIR spectral patterns. In conclusion, NIR spectroscopy as a tool is a promising and very rapid way to detect differences between exhaust air samples based on still not clearly defined circumstances triggered during a fattening period and the availability of an exhaust air cleaning system. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

Prediction of essential oil content of oregano by hand-held and Fourier transform NIR spectroscopy.

PubMed

Camps, Cédric; Gérard, Marianne; Quennoz, Mélanie; Brabant, Cécile; Oberson, Carine; Simonnet, Xavier

2014-05-01

In the framework of a breeding programme, the analysis of hundreds of oregano samples to determine their essential oil content (EOC) is time-consuming and expensive in terms of labour. Therefore developing a new method that is rapid, accurate and less expensive to use would be an asset to breeders. The aim of the present study was to develop a method based on near-inrared (NIR) spectroscopy to determine the EOC of oregano dried powder. Two spectroscopic approaches were compared, the first using a hand-held NIR device and the second a Fourier transform (FT) NIR spectrometer. Hand-held NIR (1000-1800 nm) measurements and partial least squares regression allowed the determination of EOC with R² and SEP values of 0.58 and 0.81 mL per 100 g dry matter (DM) respectively. Measurements with FT-NIR (1000-2500 nm) allowed the determination of EOC with R² and SEP values of 0.91 and 0.68 mL per 100 g DM respectively. RPD, RER and RPIQ values for the model implemented with FT-NIR data were satisfactory for screening application, while those obtained with hand-held NIR data were below the level required to consider the model as enough accurate for screening application. The FT-NIR approach allowed the development of an accurate model for EOC prediction. Although the hand-held NIR approach is promising, it needs additional development before it can be used in practice. © 2013 Society of Chemical Industry.

High contrast near-infrared polarized reflectance images of demineralization on tooth buccal and occlusal surfaces at lambda = 1310-nm.

PubMed

Wu, J; Fried, D

2009-03-01

Sound enamel manifests peak transparency in the near-IR (NIR) at 1310-nm, therefore the near-IR is ideally suited for high contrast imaging of dental caries. The purpose of this study was to acquire images of early demineralized enamel on the buccal and occlusal surfaces of extracted human teeth using NIR reflectance imaging and compare the contrast of those images with the contrast of images taken using other methods. Fifteen human molars were used in this in vitro study. Teeth were painted with a clear acid-resistant varnish, leaving two 2 mm x 2 mm windows on the buccal and occlusal surfaces of each tooth for demineralization. Artificial lesions were produced in the exposed windows after a 2-day exposure to a demineralizing solution at pH 4.5. Lesions were imaged using NIR transillumination, NIR and visible light reflectance, and fluorescence imaging methods. Crossed polarizers were used where appropriate to improve contrast. Polarization sensitive optical coherence tomography (PS-OCT) was also used to non-destructively assess the depth and severity of demineralization in each sample window. NIR reflectance imaging had the highest image contrast for both the buccal and occlusal groups and it was significantly higher contrast than visible light reflectance (P < 0.05). The results of the study suggest that NIR reflectance imaging is a promising new method for acquiring high contrast images of early demineralization on tooth surfaces. Copyright 2009 Wiley-Liss, Inc.

Comparison of near infrared spectra within broiler breast fillets deboned at different postmortem time

USDA-ARS?s Scientific Manuscript database

Near infrared (NIR) spectroscopy has been used to predict texture quality of broiler breast fillets. Sampling is an important issue in NIR measurements to obtain accurate results. There are no research papers about sampling of chicken breast fillet for NIR measurement. The objective of this study wa...

Near and mid infrared spectroscopy and multivariate data analysis in studies of oxidation of edible oils.

PubMed

Wójcicki, Krzysztof; Khmelinskii, Igor; Sikorski, Marek; Sikorska, Ewa

2015-11-15

Infrared spectroscopic techniques and chemometric methods were used to study oxidation of olive, sunflower and rapeseed oils. Accelerated oxidative degradation of oils at 60°C was monitored using peroxide values and FT-MIR ATR and FT-NIR transmittance spectroscopy. Principal component analysis (PCA) facilitated visualization and interpretation of spectral changes occurring during oxidation. Multivariate curve resolution (MCR) method found three spectral components in the NIR and MIR spectral matrix, corresponding to the oxidation products, and saturated and unsaturated structures. Good quantitative relation was found between peroxide value and contribution of oxidation products evaluated using MCR--based on NIR (R(2) = 0.890), MIR (R(2) = 0.707) and combined NIR and MIR (R(2) = 0.747) data. Calibration models for prediction peroxide value established using partial least squares (PLS) regression were characterized for MIR (R(2) = 0.701, RPD = 1.7), NIR (R(2) = 0.970, RPD = 5.3), and combined NIR and MIR data (R(2) = 0.954, RPD = 3.1). Copyright © 2015 Elsevier Ltd. All rights reserved.

Determination of Protein Content by NIR Spectroscopy in Protein Powder Mix Products.

PubMed

Ingle, Prashant D; Christian, Roney; Purohit, Piyush; Zarraga, Veronica; Handley, Erica; Freel, Keith; Abdo, Saleem

2016-01-01

Protein is a principal component in commonly used dietary supplements and health food products. The analysis of these products, within the consumer package form, is of critical importance for the purpose of ensuring quality and supporting label claims. A rapid test method was developed using near-infrared (NIR) spectroscopy as a compliment to current protein determination by the Dumas combustion method. The NIR method was found to be a rapid, low-cost, and green (no use of chemicals and reagents) complimentary technique. The protein powder samples analyzed in this study were in the range of 22-90% protein. The samples were prepared as mixtures of soy protein, whey protein, and silicon dioxide ingredients, which are common in commercially sold protein powder drink-mix products in the market. A NIR regression model was developed with 17 samples within the constituent range and was validated with 20 independent samples of known protein levels (85-88%). The results show that the NIR method is capable of predicting the protein content with a bias of ±2% and a maximum bias of 3% between NIR and the external Dumas method.

Anatomical guidance for functional near-infrared spectroscopy: AtlasViewer tutorial

PubMed Central

Aasted, Christopher M.; Yücel, Meryem A.; Cooper, Robert J.; Dubb, Jay; Tsuzuki, Daisuke; Becerra, Lino; Petkov, Mike P.; Borsook, David; Dan, Ippeita; Boas, David A.

2015-01-01

Abstract. Functional near-infrared spectroscopy (fNIRS) is an optical imaging method that is used to noninvasively measure cerebral hemoglobin concentration changes induced by brain activation. Using structural guidance in fNIRS research enhances interpretation of results and facilitates making comparisons between studies. AtlasViewer is an open-source software package we have developed that incorporates multiple spatial registration tools to enable structural guidance in the interpretation of fNIRS studies. We introduce the reader to the layout of the AtlasViewer graphical user interface, the folder structure, and user files required in the creation of fNIRS probes containing sources and detectors registered to desired locations on the head, evaluating probe fabrication error and intersubject probe placement variability, and different procedures for estimating measurement sensitivity to different brain regions as well as image reconstruction performance. Further, we detail how AtlasViewer provides a generic head atlas for guiding interpretation of fNIRS results, but also permits users to provide subject-specific head anatomies to interpret their results. We anticipate that AtlasViewer will be a valuable tool in improving the anatomical interpretation of fNIRS studies. PMID:26157991

Nondestructive estimation of tracheid length from sections of radial wood strips by near infrared spectroscopy

Treesearch

Laurence R. Schimleck; P. David Jones; Gary F. Peter; F. Daniels; Alexander Clarklll

2004-01-01

The use of calibrated near infrared (NIR) spectroscopy for predicting tracheid length of Pinus taeda L. (loblolly pine) wood samples is described. Ten-mm sections of 14 P. taeda radial strips were selected and NIR spectra obtained from the radial longitudinal face of each section. The fibers in these sections were characterized in terms of arithmetic and length-...

A preliminary study of preservative retention and penetration in ACQ-treated timbers using near infrared spectroscopy

Treesearch

Chi-Leung So; Thomas L. Eberhardt; Stan T. Lebow; Leslie H. Groom

2006-01-01

Near infrared (NIR) spectroscopy has been previously used in our laboratory to predict copper, chromium, and arsenic levels in samples of chromated copper arsenate (CCA)-treated wood. In the present study, we utilized our custom-made NIR scanning system, NIRVANA (near infrared visual and automated numerical analysis), to scan cross sections of ACQ (alkaline copper quat...

Near infrared spectroscopy for the nondestructive estimation of clear wood properties of Pinus taeda L. from the southern United States

Treesearch

Laurence R. Schimleck; P. David Jones; Alexander Clark; Richard F. Daniels; Gary F. Peter

2005-01-01

The estimation of specific gravity (SG), modulus of elasticity (MOE), and modulus of rupture (MOR) of loblolly pine (Pinus taeda L.) clear wood samples from a diverse range of sites across the southern United States was investigated using near infrared (NIR) spectroscopy. NIR spectra were obtained from the radial and cross sectional (original, rough...

Feasibility of using near-infrared (NIR) spectroscopy for quantitative detection of Kojic Acid in wheat flour

USDA-ARS?s Scientific Manuscript database

The possibility of using NIR spectroscopy technology to detect kojic acid (KA) added in wheat flour was studied. Three common types of white flour samples, i.e. high-gluten flour, plain flour and low-gluten flour were added with different contents of KA (0.0%, 0.5%, 1.0%, 3.0%, 5.0%, and 10.0%) resp...

Growth of near-infrared spectroscopy in pharmaceutical and medical sciences

NASA Astrophysics Data System (ADS)

Ciurczak, Emil W.

2002-06-01

Near-IR Spectroscopy (NIRS) is used extensively in the health services industries: medical research, pharmaceutical production, and bioprocessing. NIRS Is rugged, simple to operate, flexible, and relatively inexpensive. It may be used to monitor the progress biochemical reactions. It is used to control mixing, blending, drying, and coating in pharmaceutical production and is used for imaging and chemical determinations in living patients.

Monitoring ibuprofen-nicotinamide cocrystal formation during solvent free continuous cocrystallization (SFCC) using near infrared spectroscopy as a PAT tool.

PubMed

Kelly, A L; Gough, T; Dhumal, R S; Halsey, S A; Paradkar, A

2012-04-15

The purpose of this work was to explore NIR spectroscopy as a PAT tool to monitor the formation of ibuprofen and nicotinamide cocrystals during extrusion based solvent free continuous cocrystallization (SFCC). Drug and co-former were gravimetrically fed into a heated co-rotating twin screw extruder to form cocrystals. Real-time process monitoring was performed using a high temperature NIR probe in the extruder die to assess cocrystal content and subsequently compared to off-line powder X-ray diffraction measurements. The effect of processing variables, such as temperature and mixing intensity, on the extent of cocrystal formation was investigated. NIR spectroscopy was sensitive to cocrystal formation with the appearance of new peaks and peak shifts, particularly in the 4800-5200 cm(-1) wave-number region. PXRD confirmed an increased conversion of the mixture into cocrystal with increase in barrel temperature and screw mixing intensity. A decrease in screw rotation speed also provided improved cocrystal yield due to the material experiencing longer residence times within the process. A partial least squares analysis in this region of NIR spectrum correlated well with PXRD data, providing a best fit with cocrystal conversion when a limited range of process conditions were considered, for example a single set temperature. The study suggests that NIR spectroscopy could be used to monitor cocrystal purity on an industrial scale using this continuous, solvent-free process. Copyright © 2011 Elsevier B.V. All rights reserved.

Compensation of spectral artifacts in dual-modality intravascular optical coherence tomography and near-infrared spectroscopy (Conference Presentation)

NASA Astrophysics Data System (ADS)

Fard, Ali M.; Gardecki, Joseph A.; Ughi, Giovanni J.; Hyun, Chulho; Tearney, Guillermo J.

2016-02-01

Intravascular optical coherence tomography (OCT) is a high-resolution catheter-based imaging method that provides three-dimensional microscopic images of coronary artery in vivo, facilitating coronary artery disease treatment decisions based on detailed morphology. Near-infrared spectroscopy (NIRS) has proven to be a powerful tool for identification of lipid-rich plaques inside the coronary walls. We have recently demonstrated a dual-modality intravascular imaging technology that integrates OCT and NIRS into one imaging catheter using a two-fiber arrangement and a custom-made dual-channel fiber rotary junction. It therefore enables simultaneous acquisition of microstructural and composition information at 100 frames/second for improved diagnosis of coronary lesions. The dual-modality OCT-NIRS system employs a single wavelength-swept light source for both OCT and NIRS modalities. It subsequently uses a high-speed photoreceiver to detect the NIRS spectrum in the time domain. Although use of one light source greatly simplifies the system configuration, such light source exhibits pulse-to-pulse wavelength and intensity variation due to mechanical scanning of the wavelength. This can be in particular problematic for NIRS modality and sacrifices the reliability of the acquired spectra. In order to address this challenge, here we developed a robust data acquisition and processing method that compensates for the spectral variations of the wavelength-swept light source. The proposed method extracts the properties of the light source, i.e., variation period and amplitude from a reference spectrum and subsequently calibrates the NIRS datasets. We have applied this method on datasets obtained from cadaver human coronary arteries using a polygon-scanning (1230-1350nm) OCT system, operating at 100,000 sweeps per second. The results suggest that our algorithm accurately and robustly compensates the spectral variations and visualizes the dual-modality OCT-NIRS images. These findings are therefore crucial for the practical application and clinical translation of dual-modality intravascular OCT-NIRS imaging when the same swept sources are used for both OCT and spectroscopy.

Estimates of diet selection in cattle grazing cornstalk residues by measurement of chemical composition and near infrared reflectance spectroscopy of diet samples collected by ruminal evacuation.

PubMed

Petzel, Emily A; Smart, Alexander J; St-Pierre, Benoit; Selman, Susan L; Bailey, Eric A; Beck, Erin E; Walker, Julie A; Wright, Cody L; Held, Jeffrey E; Brake, Derek W

2018-05-04

Six ruminally cannulated cows (570 ± 73 kg) fed corn residues were placed in a 6 × 6 Latin square to evaluate predictions of diet composition from ruminally collected diet samples. After complete ruminal evacuation, cows were fed 1-kg meals (dry matter [DM]-basis) containing different combinations of cornstalk and leaf and husk (LH) residues in ratios of 0:100, 20:80, 40:60, 60:40, 80:20, and 100:0. Diet samples from each meal were collected by removal of ruminal contents after 1-h and were either unrinsed, hand-rinsed or machine-rinsed to evaluate effects of endogenous compounds on predictions of diet composition. Diet samples were analyzed for neutral (NDF) and acid (ADF) detergent fiber, acid detergent insoluble ash (ADIA), acid detergent lignin (ADL), crude protein (CP), and near infrared reflectance spectroscopy (NIRS) to calculate diet composition. Rinsing type increased NDF and ADF content and decreased ADIA and CP content of diet samples (P < 0.01). Rinsing tended to increase (P < 0.06) ADL content of diet samples. Differences in concentration between cornstalk and LH residues within each chemical component were standardized by calculating a coefficient of variation (CV). Accuracy and precision of estimates of diet composition were analyzed by regressing predicted diet composition and known diet composition. Predictions of diet composition were improved by increasing differences in concentration of chemical components between cornstalk and LH residues up to a CV of 22.6 ± 5.4%. Predictions of diet composition from unrinsed ADIA and machine-rinsed NIRS had the greatest accuracy (slope = 0.98 and 0.95, respectively) and large coefficients of determination (r2 = 0.86 and 0.74, respectively). Subsequently, a field study (Exp. 2) was performed to evaluate predictions of diet composition in cattle (646 ± 89 kg) grazing corn residue. Five cows were placed in 1 of 10 paddocks and allowed to graze continuously or to strip-graze corn residues. Predictions of diet composition from ADIA, ADL, and NIRS did not differ (P = 0.99), and estimates of cornstalk intake tended to be greater (P = 0.09) in strip-grazed compared to continuously grazed cows. These data indicate that diet composition can be predicted by chemical components or NIRS by ruminal collection of diet samples among cattle grazing corn residues.

Spectroscopic Detection of Caries Lesions

PubMed Central

Ruohonen, Mika; Palo, Katri; Alander, Jarmo

2013-01-01

Background. A caries lesion causes changes in the optical properties of the affected tissue. Currently a caries lesion can be detected only at a relatively late stage of development. Caries diagnosis also suffers from high interobserver variance. Methods. This is a pilot study to test the suitability of an optical diffuse reflectance spectroscopy for caries diagnosis. Reflectance visible/near-infrared spectroscopy (VIS/NIRS) was used to measure caries lesions and healthy enamel on extracted human teeth. The results were analysed with a computational algorithm in order to find a rule-based classification method to detect caries lesions. Results. The classification indicated that the measured points of enamel could be assigned to one of three classes: healthy enamel, a caries lesion, and stained healthy enamel. The features that enabled this were consistent with theory. Conclusions. It seems that spectroscopic measurements can help to reduce false positives at in vitro setting. However, further research is required to evaluate the strength of the evidence for the method's performance. PMID:27006907

Modulation of Frontoparietal Neurovascular Dynamics in Working Memory

PubMed Central

Ardestani, Allen; Shen, Wei; Darvas, Felix; Toga, Arthur W.; Fuster, Joaquin M.

2016-01-01

Our perception of the world is represented in widespread, overlapping, and interactive neuronal networks of the cerebral cortex. A majority of physiological studies on the subject have focused on oscillatory synchrony as the binding mechanism for representation and transmission of neural information. Little is known, however, about the stability of that synchrony during prolonged cognitive operations that span more than just a few seconds. The present research, in primates, investigated the dynamic patterns of oscillatory synchrony by two complementary recording methods, surface field potentials (SFPs) and near-infrared spectroscopy (NIRS). The signals were first recorded during the resting state to examine intrinsic functional connectivity. The temporal modulation of coactivation was then examined on both signals during performance of working memory ( WM) tasks with long delays (memory retention epochs). In both signals, the peristimulus period exhibited characteristic features in frontal and parietal regions. Examination of SFP signals over delays lasting tens of seconds, however, revealed alternations of synchronization and desynchronization. These alternations occurred within the same frequency bands observed in the peristimulus epoch, without a specific correspondence between any definite cognitive process (e.g., WM) and synchrony within a given frequency band. What emerged instead was a correlation between the degree of SFP signal fragmentation (in time, frequency, and brain space) and the complexity and efficiency of the task being performed. In other words, the incidence and extent of SFP transitions between synchronization and desynchronization—rather than the absolute degree of synchrony—augmented in correct task performance compared with incorrect performance or in a control task without WM demand. An opposite relationship was found in NIRS: increasing task complexity induced more uniform, rather than fragmented, NIRS coactivations. These findings indicate that the particular features of neural oscillations cannot be linearly mapped to cognitive functions. Rather, information and the cognitive operations performed on it are primarily reflected in their modulations over time. The increased complexity and fragmentation of electrical frequencies in WM may reflect the activation of hierarchically diverse cognits (cognitive networks) in that condition. Conversely, the homogeneity in coherence of NIRS responses may reflect the cumulative vascular reactions that accompany that neuroelectrical proliferation of frequencies and the longer time constant of the NIRS signal. These findings are directly relevant to the mechanisms mediating cognitive processes and to physiologically based interpretations of functional brain imaging. PMID:26679214

[Application of wavelet transform-radial basis function neural network in NIRS for determination of rifampicin and isoniazide tablets].

PubMed

Lu, Jia-hui; Zhang, Yi-bo; Zhang, Zhuo-yong; Meng, Qing-fan; Guo, Wei-liang; Teng, Li-rong

2008-06-01

A calibration model (WT-RBFNN) combination of wavelet transform (WT) and radial basis function neural network (RBFNN) was proposed for synchronous and rapid determination of rifampicin and isoniazide in Rifampicin and Isoniazide tablets by near infrared reflectance spectroscopy (NIRS). The approximation coefficients were used for input data in RBFNN. The network parameters including the number of hidden layer neurons and spread constant (SC) were investigated. WT-RBFNN model which compressed the original spectra data, removed the noise and the interference of background, and reduced the randomness, the capabilities of prediction were well optimized. The root mean square errors of prediction (RMSEP) for the determination of rifampicin and isoniazide obtained from the optimum WT-RBFNN model are 0.00639 and 0.00587, and the root mean square errors of cross-calibration (RMSECV) for them are 0.00604 and 0.00457, respectively which are superior to those obtained by the optimum RBFNN and PLS models. Regression coefficient (R) between NIRS predicted values and RP-HPLC values for rifampicin and isoniazide are 0.99522 and 0.99392, respectively and the relative error is lower than 2.300%. It was verified that WT-RBFNN model is a suitable approach to dealing with NIRS. The proposed WT-RBFNN model is convenient, and rapid and with no pollution for the determination of rifampicin and isoniazide tablets.

Canopy near-infrared reflectance and terrestrial photosynthesis.

PubMed

Badgley, Grayson; Field, Christopher B; Berry, Joseph A

2017-03-01

Global estimates of terrestrial gross primary production (GPP) remain highly uncertain, despite decades of satellite measurements and intensive in situ monitoring. We report a new approach for quantifying the near-infrared reflectance of terrestrial vegetation (NIR V ). NIR V provides a foundation for a new approach to estimate GPP that consistently untangles the confounding effects of background brightness, leaf area, and the distribution of photosynthetic capacity with depth in canopies using existing moderate spatial and spectral resolution satellite sensors. NIR V is strongly correlated with solar-induced chlorophyll fluorescence, a direct index of photons intercepted by chlorophyll, and with site-level and globally gridded estimates of GPP. NIR V makes it possible to use existing and future reflectance data as a starting point for accurately estimating GPP.

In-line monitoring of extraction process of scutellarein from Erigeron breviscapus (vant.) Hand-Mazz based on qualitative and quantitative uses of near-infrared spectroscopy.

PubMed

Wu, Yongjiang; Jin, Ye; Ding, Haiying; Luan, Lianjun; Chen, Yong; Liu, Xuesong

2011-09-01

The application of near-infrared (NIR) spectroscopy for in-line monitoring of extraction process of scutellarein from Erigeron breviscapus (vant.) Hand-Mazz was investigated. For NIR measurements, two fiber optic probes designed to transmit NIR radiation through a 2 mm pathlength flow cell were utilized to collect spectra in real-time. High performance liquid chromatography (HPLC) was used as a reference method to determine scutellarein in extract solution. Partial least squares regression (PLSR) calibration model of Savitzky-Golay smoothing NIR spectra in the 5450-10,000 cm(-1) region gave satisfactory predictive results for scutellarein. The results showed that the correlation coefficients of calibration and cross validation were 0.9967 and 0.9811, respectively, and the root mean square error of calibration and cross validation were 0.044 and 0.105, respectively. Furthermore, both the moving block standard deviation (MBSD) method and conformity test were used to identify the end point of extraction process, providing real-time data and instant feedback about the extraction course. The results obtained in this study indicated that the NIR spectroscopy technique provides an efficient and environmentally friendly approach for fast determination of scutellarein and end point control of extraction process. Copyright © 2011 Elsevier B.V. All rights reserved.

Authentication of the botanical origin of honey by near-infrared spectroscopy.

PubMed

Ruoff, Kaspar; Luginbühl, Werner; Bogdanov, Stefan; Bosset, Jacques Olivier; Estermann, Barbara; Ziolko, Thomas; Amado, Renato

2006-09-06

Fourier transform near-infrared spectroscopy (FT-NIR) was evaluated for the authentication of eight unifloral and polyfloral honey types (n = 364 samples) previously classified using traditional methods such as chemical, pollen, and sensory analysis. Chemometric evaluation of the spectra was carried out by applying principal component analysis and linear discriminant analysis. The corresponding error rates were calculated according to Bayes' theorem. NIR spectroscopy enabled a reliable discrimination of acacia, chestnut, and fir honeydew honey from the other unifloral and polyfloral honey types studied. The error rates ranged from <0.1 to 6.3% depending on the honey type. NIR proved also to be useful for the classification of blossom and honeydew honeys. The results demonstrate that near-infrared spectrometry is a valuable, rapid, and nondestructive tool for the authentication of the above-mentioned honeys, but not for all varieties studied.

Physiological denoising of BOLD fMRI data using Regressor Interpolation at Progressive Time Delays (RIPTiDe) processing of concurrent fMRI and near-infrared spectroscopy (NIRS).

PubMed

Frederick, Blaise deB; Nickerson, Lisa D; Tong, Yunjie

2012-04-15

Confounding noise in BOLD fMRI data arises primarily from fluctuations in blood flow and oxygenation due to cardiac and respiratory effects, spontaneous low frequency oscillations (LFO) in arterial pressure, and non-task related neural activity. Cardiac noise is particularly problematic, as the low sampling frequency of BOLD fMRI ensures that these effects are aliased in recorded data. Various methods have been proposed to estimate the noise signal through measurement and transformation of the cardiac and respiratory waveforms (e.g. RETROICOR and respiration volume per time (RVT)) and model-free estimation of noise variance through examination of spatial and temporal patterns. We have previously demonstrated that by applying a voxel-specific time delay to concurrently acquired near infrared spectroscopy (NIRS) data, we can generate regressors that reflect systemic blood flow and oxygenation fluctuations effects. Here, we apply this method to the task of removing physiological noise from BOLD data. We compare the efficacy of noise removal using various sets of noise regressors generated from NIRS data, and also compare the noise removal to RETROICOR+RVT. We compare the results of resting state analyses using the original and noise filtered data, and we evaluate the bias for the different noise filtration methods by computing null distributions from the resting data and comparing them with the expected theoretical distributions. Using the best set of processing choices, six NIRS-generated regressors with voxel-specific time delays explain a median of 10.5% of the variance throughout the brain, with the highest reductions being seen in gray matter. By comparison, the nine RETROICOR+RVT regressors together explain a median of 6.8% of the variance in the BOLD data. Detection of resting state networks was enhanced with NIRS denoising, and there were no appreciable differences in the bias of the different techniques. Physiological noise regressors generated using Regressor Interpolation at Progressive Time Delays (RIPTiDe) offer an effective method for efficiently removing hemodynamic noise from BOLD data. Copyright © 2012 Elsevier Inc. All rights reserved.

Industrial defect discrimination applying infrared imaging spectroscopy and artificial neural networks

NASA Astrophysics Data System (ADS)

Garcia-Allende, Pilar Beatriz; Conde, Olga M.; Madruga, Francisco J.; Cubillas, Ana M.; Lopez-Higuera, Jose M.

2008-03-01

A non-intrusive infrared sensor for the detection of spurious elements in an industrial raw material chain has been developed. The system is an extension to the whole near infrared range of the spectrum of a previously designed system based on the Vis-NIR range (400 - 1000 nm). It incorporates a hyperspectral imaging spectrograph able to register simultaneously the NIR reflected spectrum of the material under study along all the points of an image line. The working material has been different tobacco leaf blends mixed with typical spurious elements of this field such as plastics, cardboards, etc. Spurious elements are discriminated automatically by an artificial neural network able to perform the classification with a high degree of accuracy. Due to the high amount of information involved in the process, Principal Component Analysis is first applied to perform data redundancy removal. By means of the extension to the whole NIR range of the spectrum, from 1000 to 2400 nm, the characterization of the material under test is highly improved. The developed technique could be applied to the classification and discrimination of other materials, and, as a consequence of its non-contact operation it is particularly suitable for food quality control.

Monitoring of antisolvent crystallization of sodium scutellarein by combined FBRM-PVM-NIR.

PubMed

Liu, Xuesong; Sun, Di; Wang, Feng; Wu, Yongjiang; Chen, Yong; Wang, Longhu

2011-06-01

Antisolvent crystallization can be used as an alternative to cooling or evaporation for the separation and purification of solid product in the pharmaceutical industry. To improve the process understanding of antisolvent crystallization, the use of in-line tools is vital. In this study, the process analytical technology (PAT) tools including focused beam reflectance measurement (FBRM), particle video microscope (PVM), and near-infrared spectroscopy (NIRS) were utilized to monitor antisolvent crystallization of sodium scutellarein. FBRM was used to monitor chord count and chord length distribution of sodium scutellarein particles in the crystallizer, and PVM, as an in-line video camera, provided pictures imaging particle shape and dimension. In addition, a quantitative model of PLS was established by in-line NIRS to detect the concentration of sodium scutellarein in the solvent and good calibration statistics were obtained (r(2) = 0.976) with the residual predictive deviation value of 11.3. The discussion over sensitivities, strengths, and weaknesses of the PAT tools may be helpful in selection of suitable PAT techniques. These in-line techniques eliminate the need for sample preparation and offer a time-saving approach to understand and monitor antisolvent crystallization process. Copyright © 2011 Wiley-Liss, Inc.

Determination of Hemicellulose, Cellulose and Lignin in Moso Bamboo by Near Infrared Spectroscopy

PubMed Central

Li, Xiaoli; Sun, Chanjun; Zhou, Binxiong; He, Yong

2015-01-01

The contents of hemicellulose, cellulose and lignin are important for moso bamboo processing in biomass energy industry. The feasibility of using near infrared (NIR) spectroscopy for rapid determination of hemicellulose, cellulose and lignin was investigated in this study. Initially, the linear relationship between bamboo components and their NIR spectroscopy was established. Subsequently, successive projections algorithm (SPA) was used to detect characteristic wavelengths for establishing the convenient models. For hemicellulose, cellulose and lignin, 22, 22 and 20 characteristic wavelengths were obtained, respectively. Nonlinear determination models were subsequently built by an artificial neural network (ANN) and a least-squares support vector machine (LS-SVM) based on characteristic wavelengths. The LS-SVM models for predicting hemicellulose, cellulose and lignin all obtained excellent results with high determination coefficients of 0.921, 0.909 and 0.892 respectively. These results demonstrated that NIR spectroscopy combined with SPA-LS-SVM is a useful, nondestructive tool for the determinations of hemicellulose, cellulose and lignin in moso bamboo. PMID:26601657

Online monitoring of P(3HB) produced from used cooking oil with near-infrared spectroscopy.

PubMed

Cruz, Madalena V; Sarraguça, Mafalda Cruz; Freitas, Filomena; Lopes, João Almeida; Reis, Maria A M

2015-01-20

Online monitoring process for the production of polyhydroxyalkanoates (PHA), using cooking oil (UCO) as the sole carbon source and Cupriavidus necator, was developed. A batch reactor was operated and hydroxybutyrate homopolymer was obtained. The biomass reached a maximum concentration of 11.6±1.7gL(-1) with a polymer content of 63±10.7% (w/w). The yield of product on substrate was 0.77±0.04gg(-1). Near-infrared (NIR) spectroscopy was used for online monitoring of the fermentation, using a transflectance probe. Partial least squares regression was applied to relate NIR spectra with biomass, UCO and PHA concentrations in the broth. The NIR predictions were compared with values obtained by offline reference methods. Prediction errors to these parameters were 1.18, 2.37 and 1.58gL(-1) for biomass, UCO and PHA, respectively, which indicate the suitability of the NIR spectroscopy method for online monitoring and as a method to assist bioreactor control. Copyright © 2014 Elsevier B.V. All rights reserved.

Nondestructive determination of the modulus of elasticity of Fraxinus mandschurica using near-infrared spectroscopy

NASA Astrophysics Data System (ADS)

Yu, Huiling; Liang, Hao; Lin, Xue; Zhang, Yizhuo

2018-04-01

A nondestructive methodology is proposed to determine the modulus of elasticity (MOE) of Fraxinus mandschurica samples by using near-infrared (NIR) spectroscopy. The test data consisted of 150 NIR absorption spectra of the wood samples obtained using an NIR spectrometer, with the wavelength range of 900 to 1900 nm. To eliminate the high-frequency noise and the systematic variations on the baseline, Savitzky-Golay convolution combined with standard normal variate and detrending transformation was applied as data pretreated methods. The uninformative variable elimination (UVE), improved by the evolutionary Monte Carlo (EMC) algorithm and successive projections algorithm (SPA) selected three characteristic variables from full 117 variables. The predictive ability of the models was evaluated concerning the root-mean-square error of prediction (RMSEP) and coefficient of determination (Rp2) in the prediction set. In comparison with the predicted results of all the models established in the experiments, UVE-EMC-SPA-LS-SVM presented the best results with the smallest RMSEP of 0.652 and the highest Rp2 of 0.887. Thus, it is feasible to determine the MOE of F. mandschurica using NIR spectroscopy accurately.

Harvest-time prediction of apple physiological indices using fiber optic Fourier transform near-infrared spectrometer

NASA Astrophysics Data System (ADS)

Liu, Yande; Ying, Yibin; Lu, Huishan; Fu, Xiaping

2004-12-01

This work evaluates the feasibility of Fourier transform near infrared (FT-NIR) spectrometry for rapid determining the total soluble solids content and acidity of apple fruit. Intact apple fruit were measured by reflectance FT-NIR in 800-2500 nm range. FT-NIR models were developed based on partial least square (PLS) regression and principal component regress (PCR) 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 FT-NIR spectra to soluble solids content (SSC), titratable acidity (TA) and available acidity (pH). The best combination, based on the prediction results, was PLS models with respect to the logarithms of the reflectance reciprocal. Predictions with PLS models resulted standard errors of prediction (SEP) of 0.455, 0.044 and 0.068, and correlation coefficients of 0.968, 0.728 and 0.831 for SSC, TA and pH, respectively. It was concluded that by using the FT-NIR spectrometry measurement system, in the appropriate spectral range, it is possible to nondestructively assess the maturity factors of apple fruit.

Multimodal fiber-probe spectroscopy as a clinical tool for diagnosing and classifying biological tissues

NASA Astrophysics Data System (ADS)

Cicchi, Riccardo; Anand, Suresh; Fantechi, Riccardo; Giordano, Flavio; Gacci, Mauro; Conti, Valerio; Nesi, Gabriella; Buccoliero, Anna Maria; Carini, Marco; Guerrini, Renzo; Pavone, Francesco Saverio

2017-07-01

An optical fiber probe for multimodal spectroscopy was designed, developed and used for tissue diagnostics. The probe, based on a fiber bundle with optical fibers of various size and properties, allows performing spectroscopic measurements with different techniques, including fluorescence, Raman, and diffuse reflectance, using the same probe. Two visible laser diodes were used for fluorescence spectroscopy, a laser diode emitting in the NIR was used for Raman spectroscopy, and a fiber-coupled halogen lamp for diffuse reflectance. The developed probe was successfully employed for diagnostic purposes on various tissues, including brain and bladder. In particular, the device allowed discriminating healthy tissue from both tumor and dysplastic tissue as well as to perform tumor grading. The diagnostic capabilities of the method, determined using a cross-validation method with a leave-one-out approach, demonstrated high sensitivity and specificity for all the examined samples, as well as a good agreement with histopathological examination performed on the same samples. The obtained results demonstrated that the multimodal approach is crucial for improving diagnostic capabilities with respect to what can be obtained from individual techniques. The experimental setup presented here can improve diagnostic capabilities on a broad range of tissues and has the potential of being used clinically for guiding surgical resection in the near future.

NIR remission spectroscopy of turbid media

NASA Astrophysics Data System (ADS)

Krauter, P.; Foschum, F.; Kienle, A.

2013-06-01

We present a method for the determination of absorption spectra in VIS and NIR spectra of turbid media without the need for calibration. Measurements of the absorption spectra of a phantom and butter are presented.

Modeling of photon migration in the human lung using a finite volume solver

NASA Astrophysics Data System (ADS)

Sikorski, Zbigniew; Furmanczyk, Michal; Przekwas, Andrzej J.

2006-02-01

The application of the frequency domain and steady-state diffusive optical spectroscopy (DOS) and steady-state near infrared spectroscopy (NIRS) to diagnosis of the human lung injury challenges many elements of these techniques. These include the DOS/NIRS instrument performance and accurate models of light transport in heterogeneous thorax tissue. The thorax tissue not only consists of different media (e.g. chest wall with ribs, lungs) but its optical properties also vary with time due to respiration and changes in thorax geometry with contusion (e.g. pneumothorax or hemothorax). This paper presents a finite volume solver developed to model photon migration in the diffusion approximation in heterogeneous complex 3D tissues. The code applies boundary conditions that account for Fresnel reflections. We propose an effective diffusion coefficient for the void volumes (pneumothorax) based on the assumption of the Lambertian diffusion of photons entering the pleural cavity and accounting for the local pleural cavity thickness. The code has been validated using the MCML Monte Carlo code as a benchmark. The code environment enables a semi-automatic preparation of 3D computational geometry from medical images and its rapid automatic meshing. We present the application of the code to analysis/optimization of the hybrid DOS/NIRS/ultrasound technique in which ultrasound provides data on the localization of thorax tissue boundaries. The code effectiveness (3D complex case computation takes 1 second) enables its use to quantitatively relate detected light signal to absorption and reduced scattering coefficients that are indicators of the pulmonary physiologic state (hemoglobin concentration and oxygenation).

A construction of standardized near infrared hyper-spectral teeth database: a first step in the development of reliable diagnostic tool for quantification and early detection of caries

NASA Astrophysics Data System (ADS)

Bürmen, Miran; Usenik, Peter; Fidler, Aleš; Pernuš, Franjo; Likar, Boštjan

2011-03-01

Dental caries is a disease characterized by demineralization of enamel crystals leading to the penetration of bacteria into the dentin and pulp. If left untreated, the disease can lead to pain, infection and tooth loss. Early detection of enamel demineralization resulting in increased enamel porosity, commonly known as white spots, is a difficult diagnostic task. Several papers reported on near infrared (NIR) spectroscopy to be a potentially useful noninvasive spectroscopic technique for early detection of caries lesions. However, the conducted studies were mostly qualitative and did not include the critical assessment of the spectral variability of the sound and carious dental tissues and influence of the water content. Such assessment is essential for development and validation of reliable qualitative and especially quantitative diagnostic tools based on NIR spectroscopy. In order to characterize the described spectral variability, a standardized diffuse reflectance hyper-spectral database was constructed by imaging 12 extracted human teeth with natural lesions of various degrees in the spectral range from 900 to 1700 nm with spectral resolution of 10 nm. Additionally, all the teeth were imaged by digital color camera. The influence of water content on the acquired spectra was characterized by monitoring the teeth during the drying process. The images were assessed by an expert, thereby obtaining the gold standard. By analyzing the acquired spectra we were able to accurately model the spectral variability of the sound dental tissues and identify the advantages and limitations of NIR hyper-spectral imaging.

Potential of near infrared spectroscopy for the analysis of mycotoxins applied to naturally contaminated red paprika found in the Spanish market.

PubMed

Hernández-Hierro, J M; García-Villanova, R J; González-Martín, I

2008-08-01

The potential of the near infrared spectroscopy (NIRS) technique for the analysis of red paprika for aflatoxin B(1), ochratoxin A and total aflatoxins is explored. As a reference, the results from a chromatographic method with fluorescence detection (HPLC-FD) following an immunoaffinity cleanup (IAC) were employed. For the NIRS measurement, a remote reflectance fibre-optic probe was applied directly onto the samples of paprika. There was no need for pre-treatment or manipulation of the sample. The modified partial least squares (MPLS) algorithm was employed as a regression method. The multiple correlation coefficients (RSQ) and the prediction corrected standard errors (SEP(C)) were respectively 0.955 and 0.2 microg kg(-1), 0.853 and 2.3 microg kg(-1), 0.938 and 0.3 microg kg(-1) for aflatoxin B(1), ochratoxin A and total aflatoxins, respectively. The capacity for prediction of the developed model measured as ratio performance deviation (RPD) for aflatoxin B(1) (5.2), ochratoxin A (2.8) and total aflatoxins (4.4) indicate that NIRS technique using a fibre-optic probe offers an alternative for the determination of these three parameters in paprika, with an advantageously lower cost and higher speed as compared with the chemical method. Content of aflatoxin B(1) and total aflatoxins are the parameters currently employed by the food regulations to limit the levels of the four aflatoxins in many foodstuffs. In addition, aflatoxin B(1) itself is an excellent indicator for aflatoxins' contamination since it is always the most abundant and toxic.

Ex vivo optical characterization of in vivo grown tissues on dummy sensor implants using double integrating spheres measurement

NASA Astrophysics Data System (ADS)

Sharma, Sandeep; Goodarzi, Mohammad; Aernouts, Ben; Gellynck, Karolien; Vlaminck, Lieven; Bockstaele, Ronny; Cornelissen, Maria; Ramon, Herman; Saeys, Wouter

2014-05-01

Near infrared spectroscopy offers a promising technological platform for continuous glucose monitoring in the human body. NIR measurements can be performed in vivo with an implantable single-chip based optical NIR sensor. However, the application of NIR spectroscopy for accurate estimation of the analyte concentration in highly scattering biological systems still remains a challenge. For instance, a thin tissue layer may grow in the optical path of the sensor. As most biological tissues allow only a small fraction of the collimated light to pass, this might result in a large reduction of the light throughput. To quantify the effect of presence of a thin tissue layer in the optical path, the bulk optical properties of tissue samples grown on sensor dummies which had been implanted for several months in goats were characterized using Double Integrating Spheres and unscattered transmittance measurements. The measured values of diffuse reflectance, diffuse transmittance and collimated transmittance were used as input to Inverse Adding-Doubling algorithm to estimate the bulk optical properties of the samples. The estimates of absorption and scattering coefficients were then used to calculate the light attenuation through a thin tissue layer. Based on the lower reduction in unscattered transmittance and higher absorptivity of glucose molecules, the measurement in the combination band was found to be the better option for the implantable sensor. As the tissues were found to be highly forward scattering with very low unscattered transmittance, the diffuse transmittance measurement based sensor configuration was recommended for the implantable glucose sensor.

Functional Near Infrared Spectroscopy: Watching the Brain in Flight

NASA Technical Reports Server (NTRS)

Harrivel, Angela; Hearn, Tristan

2012-01-01

Functional Near Infrared Spectroscopy (fNIRS) is an emerging neurological sensing technique applicable to optimizing human performance in transportation operations, such as commercial aviation. Cognitive state can be determined via pattern classification of functional activations measured with fNIRS. Operational application calls for further development of algorithms and filters for dynamic artifact removal. The concept of using the frequency domain phase shift signal to tune a Kalman filter is introduced to improve the quality of fNIRS signals in realtime. Hemoglobin concentration and phase shift traces were simulated for four different types of motion artifact to demonstrate the filter. Unwanted signal was reduced by at least 43%, and the contrast of the filtered oxygenated hemoglobin signal was increased by more than 100% overall. This filtering method is a good candidate for qualifying fNIRS signals in real time without auxiliary sensors

Functional Near Infrared Spectroscopy: Watching the Brain in Flight

NASA Technical Reports Server (NTRS)

Harrivel, Angela; Hearn, Tristan A.

2012-01-01

Functional Near Infrared Spectroscopy (fNIRS) is an emerging neurological sensing technique applicable to optimizing human performance in transportation operations, such as commercial aviation. Cognitive state can be determined via pattern classification of functional activations measured with fNIRS. Operational application calls for further development of algorithms and filters for dynamic artifact removal. The concept of using the frequency domain phase shift signal to tune a Kalman filter is introduced to improve the quality of fNIRS signals in real-time. Hemoglobin concentration and phase shift traces were simulated for four different types of motion artifact to demonstrate the filter. Unwanted signal was reduced by at least 43%, and the contrast of the filtered oxygenated hemoglobin signal was increased by more than 100% overall. This filtering method is a good candidate for qualifying fNIRS signals in real time without auxiliary sensors.

Near Infrared Spectroscopy for On-line Monitoring of Alkali- Free Cloth/Phenolic Resin Prepreg During Manufacture

PubMed Central

Jiang, Bo; Huang, Yu Dong

2007-01-01

A NIR method was developed for the on-line monitoring of alkali-free cloth/phenolic resin prepreg during its manufacturing process. First, the sizing content of the alkali-free cloth was analyzed, and then the resin, soluble resin and volatiles content of the prepreg was analyzed simultaneously using the FT-NIR spectrometer. Partial least square (PLS) regression was used to develop the calibration models, which for the sizing content was preprocessed by 1stDER +MSC, for the volatile content by 1stDER +VN, for the soluble resin content by 1stDER +MSC and for the resin content by the VN spectral data preprocessing method. RMSEP of the prediction model for the sizing content was 0.732 %, for the resin content it was 0.605, for the soluble resin content it was 0.101 and for volatiles content it was 0.127. The results of the paired t-test revealed that there was no significant difference between the NIR method and the standard method. The NIR spectroscopy method could be used to predict the resin, soluble resin and the volatiles content of the prepreg simultaneously, as well as sizing content of alkali-free cloth. The processing parameters of the prepreg during manufacture could be adjusted quickly with the help of the NIR analysis results. The results indicated that the NIR spectroscopy method was sufficiently accurate and effective for the on-line monitoring of alkali-free cloth/phenolic resin prepreg.

An evaluation of the use of near infrared (NIR) spectroscopy to identify water and oil-borne preservatives

Treesearch

Chi-Leung So; Stan T. Lebow; Leslie H. Groom; Todd F. Shupe

2003-01-01

In this research we experimented with a new and rapid way of analyzing wood. Near Infrared (NIR)spectroscopy together with multivariate analysis is becoming a widely used technique in the field of forest products especially for property determination and is already firmly established in the pulp and paper industry. This method is ideal for the chemical analysis of wood...

Using an optimal CC-PLSR-RBFNN model and NIR spectroscopy for the starch content determination in corn

NASA Astrophysics Data System (ADS)

Jiang, Hao; Lu, Jiangang

2018-05-01

Corn starch is an important material which has been traditionally used in the fields of food and chemical industry. In order to enhance the rapidness and reliability of the determination for starch content in corn, a methodology is proposed in this work, using an optimal CC-PLSR-RBFNN calibration model and near-infrared (NIR) spectroscopy. The proposed model was developed based on the optimal selection of crucial parameters and the combination of correlation coefficient method (CC), partial least squares regression (PLSR) and radial basis function neural network (RBFNN). To test the performance of the model, a standard NIR spectroscopy data set was introduced, containing spectral information and chemical reference measurements of 80 corn samples. For comparison, several other models based on the identical data set were also briefly discussed. In this process, the root mean square error of prediction (RMSEP) and coefficient of determination (Rp2) in the prediction set were used to make evaluations. As a result, the proposed model presented the best predictive performance with the smallest RMSEP (0.0497%) and the highest Rp2 (0.9968). Therefore, the proposed method combining NIR spectroscopy with the optimal CC-PLSR-RBFNN model can be helpful to determine starch content in corn.

Correlation between near infrared spectroscopy and electrical techniques in measuring skin moisture content

NASA Astrophysics Data System (ADS)

Mohamad, M.; Sabbri, A. R. M.; Mat Jafri, M. Z.; Omar, A. F.

2014-11-01

Near infrared (NIR) spectroscopy technique serves as an important tool for the measurement of moisture content of skin owing to the advantages it has over the other techniques. The purpose of the study is to develop a correlation between NIR spectrometer with electrical conventional techniques for skin moisture measurement. A non-invasive measurement of moisture content of skin was performed on different part of human face and hand under control environment (temperature 21 ± 1 °C, relative humidity 45 ± 5 %). Ten healthy volunteers age between 21-25 (male and female) participated in this study. The moisture content of skin was measured using DermaLab® USB Moisture Module, Scalar Moisture Checker and NIR spectroscopy (NIRQuest). Higher correlation was observed between NIRQuest and Dermalab moisture probe with a coefficient of determination (R2) above 70 % for all the subjects. However, the value of R2 between NIRQuest and Moisture Checker was observed to be lower with the R2 values ranges from 51.6 to 94.4 %. The correlation of NIR spectroscopy technique successfully developed for measuring moisture content of the skin. The analysis of this correlation can help to establish novel instruments based on an optical system in clinical used especially in the dermatology field.

Measurement of process variables in solid-state fermentation of wheat straw using FT-NIR spectroscopy and synergy interval PLS algorithm

NASA Astrophysics Data System (ADS)

Jiang, Hui; Liu, Guohai; Mei, Congli; Yu, Shuang; Xiao, Xiahong; Ding, Yuhan

2012-11-01

The feasibility of rapid determination of the process variables (i.e. pH and moisture content) in solid-state fermentation (SSF) of wheat straw using Fourier transform near infrared (FT-NIR) spectroscopy was studied. Synergy interval partial least squares (siPLS) algorithm was implemented to calibrate regression model. The number of PLS factors and the number of subintervals were optimized simultaneously by cross-validation. The performance of the prediction model was evaluated according to the root mean square error of cross-validation (RMSECV), the root mean square error of prediction (RMSEP) and the correlation coefficient (R). The measurement results of the optimal model were obtained as follows: RMSECV = 0.0776, Rc = 0.9777, RMSEP = 0.0963, and Rp = 0.9686 for pH model; RMSECV = 1.3544% w/w, Rc = 0.8871, RMSEP = 1.4946% w/w, and Rp = 0.8684 for moisture content model. Finally, compared with classic PLS and iPLS models, the siPLS model revealed its superior performance. The overall results demonstrate that FT-NIR spectroscopy combined with siPLS algorithm can be used to measure process variables in solid-state fermentation of wheat straw, and NIR spectroscopy technique has a potential to be utilized in SSF industry.

Growth of indium gallium arsenide thin film on silicon substrate by MOCVD technique

NASA Astrophysics Data System (ADS)

Chowdhury, Sisir; Das, Anish; Banerji, Pallab

2018-05-01

Indium gallium arsenide (InGaAs) thin film with indium phosphide (InP) buffer has been grown on p-type silicon (100) by Metal Organic Chemical Vapor Deposition (MOCVD) technique. To get a lattice matched substrate an Indium Phosphide buffer thin film is deposited onto Si substrate prior to InGaAs growth. The grown films have been investigated by UV-Vis-NIR reflectance spectroscopy. The band gap energy of the grown InGaAs thin films determined to be 0.82 eV from reflectance spectrum and the films are found to have same thickness for growth between 600 °C and 650 °C. Crystalline quality of the grown films has been studied by grazing incidence X-ray diffractometry (GIXRD).

A New Platform for Investigating In-Situ NIR Reflectance in Snow

NASA Astrophysics Data System (ADS)

Johnson, M.; Taubenheim, J. R. L.; Stevenson, R.; Eldred, D.

2017-12-01

In-situ near infrared (NIR) reflectance measurements of the snowpack have been shown to have correlations to valuable snowpack properties. To-date many studies take these measurements by digging a pit and setting up a NIR camera to take images of the wall. This setup is cumbersome, making it challenging to investigate things like spatial variability. Over the course of 3 winters, a new device has been developed capable of mitigating some of the downfalls of NIR open pit photography. This new instrument is a NIR profiler capable of taking NIR reflectance measurements without digging a pit, with most measurements taking less than 30 seconds to retrieve data. The latest prototype is built into a ski pole and automatically transfers data wirelessly to the users smartphone. During 2016-2017 winter, the device was used by 37 different users resulting in over 4000 measurements in the Western United States, demonstrating a dramatic reduction in time to data when compared to other methods. Presented here are some initial findings from a full winter of using the ski pole version of this device.

Covering Materials Incorporating Radiation-Preventing Techniques to Meet Greenhouse Cooling Challenges in Arid Regions: A Review

PubMed Central

Abdel-Ghany, Ahmed M.; Al-Helal, Ibrahim M.; Alzahrani, Saeed M.; Alsadon, Abdullah A.; Ali, Ilias M.; Elleithy, Rabeh M.

2012-01-01

Cooling greenhouses is essential to provide a suitable environment for plant growth in arid regions characterized by brackish water resources. However, using conventional cooling methods are facing many challenges. Filtering out near infra-red radiation (NIR) at the greenhouse cover can significantly reduce the heating load and can solve the overheating problem of the greenhouse air. This paper is to review (i) the problems of using conventional cooling methods and (ii) the advantages of greenhouse covers that incorporate NIR reflectors. This survey focuses on how the cover type affects the transmittance of photosynthetically active radiation (PAR), the reflectance or absorptance of NIR and the greenhouse air temperature. NIR-reflecting plastic films seem to be the most suitable, low cost and simple cover for greenhouses under arid conditions. Therefore, this review discusses how various additives should be incorporated in plastic film to increase its mechanical properties, durability and ability to stand up to extremely harsh weather. Presently, NIR-reflecting covers are able to reduce greenhouse air temperature by no more than 5°C. This reduction is not enough in regions where the ambient temperature may exceed 45°C in summer. There is a need to develop improved NIR-reflecting plastic film covers. PMID:22629223

A system for simultaneous near-infrared reflectance and transillumination imaging of occlusal carious lesions

NASA Astrophysics Data System (ADS)

Simon, Jacob C.; Darling, Cynthia L.; Fried, Daniel

2016-02-01

Clinicians need technologies to improve the diagnosis of questionable occlusal carious lesions (QOC's) and determine if decay has penetrated to the underlying dentin. Assessing lesion depth from near-infrared (NIR) images holds great potential due to the high transparency of enamel and stain to NIR light at λ=1300-1700-nm, which allows direct visualization and quantified measurements of enamel demineralization. Unfortunately, NIR reflectance measurements alone are limited in utility for approximating occlusal lesion depth >200-μm due to light attenuation from the lesion body. Previous studies sought to combine NIR reflectance and transillumination measurements taken at λ=1300-nm in order to estimate QOC depth and severity. The objective of this study was to quantify the change in lesion contrast and size measured from multispectral NIR reflectance and transillumination images of natural occlusal carious lesions with increasing lesion depth and severity in order to determine the optimal multimodal wavelength combinations for estimating QOC depth. Extracted teeth with varying amounts of natural occlusal decay were measured using a multispectral-multimodal NIR imaging system at prominent wavelengths within the λ=1300-1700-nm spectral region. Image analysis software was used to calculate lesion contrast and area values between sound and carious enamel regions.

Prediction of canned black bean texture (Phaseolus vulgaris L.) from intact dry seeds using visible/near infrared spectroscopy and hyperspectral imaging data.

PubMed

Mendoza, Fernando A; Cichy, Karen A; Sprague, Christy; Goffnett, Amanda; Lu, Renfu; Kelly, James D

2018-01-01

Texture is a major quality parameter for the acceptability of canned whole beans. Prior knowledge of this quality trait before processing would be useful to guide variety development by bean breeders and optimize handling protocols by processors. The objective of this study was to evaluate and compare the predictive power of visible and near infrared reflectance spectroscopy (visible/NIRS, 400-2498 nm) and hyperspectral imaging (HYPERS, 400-1000 nm) techniques for predicting texture of canned black beans from intact dry seeds. Black beans were grown in Michigan (USA) over three field seasons. The samples exhibited phenotypic variability for canned bean texture due to genetic variability and processing practice. Spectral preprocessing methods (i.e. smoothing, first and second derivatives, continuous wavelet transform, and two-band ratios), coupled with a feature selection method, were tested for optimizing the prediction accuracy in both techniques based on partial least squares regression (PLSR) models. Visible/NIRS and HYPERS were effective in predicting texture of canned beans using intact dry seeds, as indicated by their correlation coefficients for prediction (R pred ) and standard errors of prediction (SEP). Visible/NIRS was superior (R pred = 0.546-0.923, SEP = 7.5-1.9 kg 100 g -1 ) to HYPERS (R pred = 0.401-0.883, SEP = 7.6-2.4 kg 100 g -1 ), which is likely due to the wider wavelength range collected in visible/NIRS. However, a significant improvement was reached in both techniques when the two-band ratios preprocessing method was applied to the data, reducing SEP by at least 10.4% and 16.2% for visible/NIRS and HYPERS, respectively. Moreover, results from using the combination of the three-season data sets based on the two-band ratios showed that visible/NIRS (R pred = 0.886, SEP = 4.0 kg 100 g -1 ) and HYPERS (R pred = 0.844, SEP = 4.6 kg 100 g -1 ) models were consistently successful in predicting texture over a wide range of measurements. Visible/NIRS and HYPERS have great potential for predicting the texture of canned beans; the robustness of the models is impacted by genotypic diversity, planting year and phenotypic variability for canned bean texture used for model building, and hence, robust models can be built based on data sets with high phenotypic diversity in textural properties, and periodically maintained and updated with new data. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Semi-quantitative prediction of a multiple API solid dosage form with a combination of vibrational spectroscopy methods.

PubMed

Hertrampf, A; Sousa, R M; Menezes, J C; Herdling, T

2016-05-30

Quality control (QC) in the pharmaceutical industry is a key activity in ensuring medicines have the required quality, safety and efficacy for their intended use. QC departments at pharmaceutical companies are responsible for all release testing of final products but also all incoming raw materials. Near-infrared spectroscopy (NIRS) and Raman spectroscopy are important techniques for fast and accurate identification and qualification of pharmaceutical samples. Tablets containing two different active pharmaceutical ingredients (API) [bisoprolol, hydrochlorothiazide] in different commercially available dosages were analysed using Raman- and NIR Spectroscopy. The goal was to define multivariate models based on each vibrational spectroscopy to discriminate between different dosages (identity) and predict their dosage (semi-quantitative). Furthermore the combination of spectroscopic techniques was investigated. Therefore, two different multiblock techniques based on PLS have been applied: multiblock PLS (MB-PLS) and sequential-orthogonalised PLS (SO-PLS). NIRS showed better results compared to Raman spectroscopy for both identification and quantitation. The multiblock techniques investigated showed that each spectroscopy contains information not present or captured with the other spectroscopic technique, thus demonstrating that there is a potential benefit in their combined use for both identification and quantitation purposes. Copyright © 2016 Elsevier B.V. All rights reserved.

Simultaneous signal reconstruction from both superficial and deep tissue for fNIRS using depth-selective filtering method

NASA Astrophysics Data System (ADS)

Fujii, M.

2017-07-01

Two variations of a depth-selective back-projection filter for functional near-infrared spectroscopy (fNIRS) systems are introduced. The filter comprises a depth-selective algorithm that uses inverse problems applied to an optically diffusive multilayer medium. In this study, simultaneous signal reconstruction of both superficial and deep tissue from fNIRS experiments of the human forehead using a prototype of a CW-NIRS system is demonstrated.

High-throughput NIR spectroscopic (NIRS) detection of microplastics in soil.

PubMed

Paul, Andrea; Wander, Lukas; Becker, Roland; Goedecke, Caroline; Braun, Ulrike

2018-05-12

The increasing pollution of terrestrial and aquatic ecosystems with plastic debris leads to the accumulation of microscopic plastic particles of still unknown amount. To monitor the degree of contamination, analytical methods are urgently needed, which help to quantify microplastics (MP). Currently, time-costly purified materials enriched on filters are investigated both by micro-infrared spectroscopy and/or micro-Raman. Although yielding precise results, these techniques are time consuming, and are restricted to the analysis of a small part of the sample in the order of few micrograms. To overcome these problems, we tested a macroscopic dimensioned near-infrared (NIR) process-spectroscopic method in combination with chemometrics. For calibration, artificial MP/ soil mixtures containing defined ratios of polyethylene, polyethylene terephthalate, polypropylene, and polystyrene with diameters < 125 μm were prepared and measured by a process FT-NIR spectrometer equipped with a fiber-optic reflection probe. The resulting spectra were processed by chemometric models including support vector machine regression (SVR), and partial least squares discriminant analysis (PLS-DA). Validation of models by MP mixtures, MP-free soils, and real-world samples, e.g., fermenter residue, suggests a reliable detection and a possible classification of MP at levels above 0.5 to 1.0 mass% depending on the polymer. The benefit of the combined NIRS chemometric approach lies in the rapid assessment whether soil contains MP, without any chemical pretreatment. The method can be used with larger sample volumes and even allows for an online prediction and thus meets the demand of a high-throughput method.

A quantitative comparison of simultaneous BOLD fMRI and NIRS recordings during functional brain activation

NASA Technical Reports Server (NTRS)

Strangman, Gary; Culver, Joseph P.; Thompson, John H.; Boas, David A.; Sutton, J. P. (Principal Investigator)

2002-01-01

Near-infrared spectroscopy (NIRS) has been used to noninvasively monitor adult human brain function in a wide variety of tasks. While rough spatial correspondences with maps generated from functional magnetic resonance imaging (fMRI) have been found in such experiments, the amplitude correspondences between the two recording modalities have not been fully characterized. To do so, we simultaneously acquired NIRS and blood-oxygenation level-dependent (BOLD) fMRI data and compared Delta(1/BOLD) (approximately R(2)(*)) to changes in oxyhemoglobin, deoxyhemoglobin, and total hemoglobin concentrations derived from the NIRS data from subjects performing a simple motor task. We expected the correlation with deoxyhemoglobin to be strongest, due to the causal relation between changes in deoxyhemoglobin concentrations and BOLD signal. Instead we found highly variable correlations, suggesting the need to account for individual subject differences in our NIRS calculations. We argue that the variability resulted from systematic errors associated with each of the signals, including: (1) partial volume errors due to focal concentration changes, (2) wavelength dependence of this partial volume effect, (3) tissue model errors, and (4) possible spatial incongruence between oxy- and deoxyhemoglobin concentration changes. After such effects were accounted for, strong correlations were found between fMRI changes and all optical measures, with oxyhemoglobin providing the strongest correlation. Importantly, this finding held even when including scalp, skull, and inactive brain tissue in the average BOLD signal. This may reflect, at least in part, the superior contrast-to-noise ratio for oxyhemoglobin relative to deoxyhemoglobin (from optical measurements), rather than physiology related to BOLD signal interpretation.

[Alfalfa quality evaluation in the field by near-infrared reflectance spectroscopy].

PubMed

Xu, Rui-Xuan; Li, Dong-Ning; Yang, Dong-Hai; Lin, Jian-Hai; Xiang, Min; Zhang, Ying-Jun

2013-11-01

To explore the feasibility of using near-infrared reflectance spectroscopy (NIRS) to evaluate alfalfa quality rapidly in the field and try to find the appropriate machine and sample preparation method, the representative population of 170 fresh alfalfa samples collected from different regions with different stages and different cuts were scanned by a portable NIRS spectrometer (1 100 - 1 800 nm). This is the first time to build models of fresh alfalfa to rapidly estimate quality in the field for harvesting in time. The calibrations of dry matter (DM), crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) were developed through the partial least squares regression (PLS). The determination coefficients of cross-validation (R2((CV)) were 0.831 4, 0.597 9, 0.803 6, 0.786 1 for DM, CP, NDF, ADF, respectively; the root mean standard error of cross-validation (RMSECV) were 1.241 1, 0.261 4, 0.990 3, 0.830 6; The determination coefficients of validation (R2(V)) were 0.815 0, 0.401 1, 0.784 9, 0.752 1 and the root mean standard errors of validation(RMSEP)were 1.06, 0.31, 0.95, 0.80 for DM, CP, NDF, ADF, respectively. For fresh alfalfa ,the calibration of DM, NDF, ADF can do rough quantitative analysis but the CP's calibration is failed. however, as CP in alfalfa hay is enough for animal and the DM, NDF and ADF is the crucial indicator for evaluating havest time, the model of DM, NDF and ADF can be used for evaluating the alfalfa quality rapidly in the field.

A case study of real-time monitoring of solid-state phase transformations in acoustically levitated particles using near infrared and Raman spectroscopy.

PubMed

Rehder, Sönke; Wu, Jian X; Laackmann, Julian; Moritz, Hans-Ulrich; Rantanen, Jukka; Rades, Thomas; Leopold, Claudia S

2013-01-23

The objective of this study was to monitor the amorphous-to-crystalline solid-state phase transformation kinetics of the model drug ibuprofen with spectroscopic methods during acoustic levitation. Chemical and physical information was obtained by real-time near infrared (NIRS) and Raman spectroscopy measurements. The recrystallisation kinetic parameters (overall recrystallisation rate constant β and the time needed to reach 50% of the equilibrated level t(50)), were determined using a multivariate curve resolution approach. The acoustic levitation device coupled with non-invasive spectroscopy enabled monitoring of the recrystallisation process of the difficult-to-handle (adhesive) amorphous sample. The application of multivariate curve resolution enabled isolation of the underlying pure spectra, which corresponded well with the reference spectra of amorphous and crystalline ibuprofen. The recrystallisation kinetic parameters were estimated from the recrystallisation profiles. While the empirical recrystallisation rate constant determined by NIR and Raman spectroscopy were comparable, the lag time for recrystallisation was significantly lower with Raman spectroscopy as compared to NIRS. This observation was explained by the high energy density of the Raman laser beam, which might have led to local heating effects of the sample and thus reduced the recrystallisation onset time. It was concluded that acoustic levitation with NIR and Raman spectroscopy combined with multivariate curve resolution allowed direct determination of the recrystallisation kinetics of amorphous drugs and thus is a promising technique for monitoring solid-state phase transformations of adhesive small-sized samples during the early phase of drug development. Copyright © 2012 Elsevier B.V. All rights reserved.

Autofluorescence Imaging With Near-Infrared Excitation:Normalization by Reflectance to Reduce Signal From Choroidal Fluorophores

PubMed Central

Cideciyan, Artur V.; Swider, Malgorzata; Jacobson, Samuel G.

2015-01-01

Purpose. We previously developed reduced-illuminance autofluorescence imaging (RAFI) methods involving near-infrared (NIR) excitation to image melanin-based fluorophores and short-wavelength (SW) excitation to image lipofuscin-based flurophores. Here, we propose to normalize NIR-RAFI in order to increase the relative contribution of retinal pigment epithelium (RPE) fluorophores. Methods. Retinal imaging was performed with a standard protocol holding system parameters invariant in healthy subjects and in patients. Normalized NIR-RAFI was derived by dividing NIR-RAFI signal by NIR reflectance point-by-point after image registration. Results. Regions of RPE atrophy in Stargardt disease, AMD, retinitis pigmentosa, choroideremia, and Leber congenital amaurosis as defined by low signal on SW-RAFI could correspond to a wide range of signal on NIR-RAFI depending on the contribution from the choroidal component. Retinal pigment epithelium atrophy tended to always correspond to high signal on NIR reflectance. Normalizing NIR-RAFI reduced the choroidal component of the signal in regions of atrophy. Quantitative evaluation of RPE atrophy area showed no significant differences between SW-RAFI and normalized NIR-RAFI. Conclusions. Imaging of RPE atrophy using lipofuscin-based AF imaging has become the gold standard. However, this technique involves bright SW lights that are uncomfortable and may accelerate the rate of disease progression in vulnerable retinas. The NIR-RAFI method developed here is a melanin-based alternative that is not absorbed by opsins and bisretinoid moieties, and is comfortable to view. Further development of this method may result in a nonmydriatic and comfortable imaging method to quantify RPE atrophy extent and its expansion rate. PMID:26024124

Combining near-infrared spectroscopy with electroencephalography and repetitive transcranial magnetic stimulation

NASA Astrophysics Data System (ADS)

Näsi, Tiina; Kotilahti, Kalle; Mäki, Hanna; Nissilä, Ilkka; Meriläinen, Pekka

2009-07-01

The objective of the study was to assess the usability of a near-infrared spectroscopy (NIRS) device in multimodal measurements. We combined NIRS with electroencephalography (EEG) to record hemodynamic responses and evoked potentials simultaneously, and with transcranial magnetic stimulation (TMS) to investigate hemodynamic responses to repetitive TMS (rTMS). Hemodynamic responses and visual evoked potentials (VEPs) to 3, 6, and 12 s stimuli consisting of pattern-reversing checkerboards were successfully recorded in the NIRS/EEG measurement, and ipsi- and contralateral hemodynamic responses to 0.5, 1, and 2 Hz rTMS in the NIRS/TMS measurement. In the NIRS/EEG measurements, the amplitudes of the hemodynamic responses increased from 3- to 6-s stimulus, but not from 6- to 12-s stimulus, and the VEPs showed peaks N75, P100, and N135. In the NIRS/TMS measurements, the 2-Hz stimulus produced the strongest hemodynamic responses compared to the 0.5- and 1-Hz stimuli. In two subjects oxyhemoglobin concentration decreased and in one increased as a consequence of the 2-Hz rTMS. To locate the origin of the measured NIRS responses, methods have to be developed to investigate TMS-induced scalp muscle contractions. In the future, multimodal measurements may prove useful in monitoring or treating diseases such as stroke or Alzheimer's disease.

Motion tracking and electromyography-assisted identification of mirror hand contributions to functional near-infrared spectroscopy images acquired during a finger-tapping task performed by children with cerebral palsy.

PubMed

Hervey, Nathan; Khan, Bilal; Shagman, Laura; Tian, Fenghua; Delgado, Mauricio R; Tulchin-Francis, Kirsten; Shierk, Angela; Roberts, Heather; Smith, Linsley; Reid, Dahlia; Clegg, Nancy J; Liu, Hanli; MacFarlane, Duncan; Alexandrakis, George

2014-10-01

Recent studies have demonstrated functional near-infrared spectroscopy (fNIRS) to be a viable and sensitive method for imaging sensorimotor cortex activity in children with cerebral palsy (CP). However, during unilateral finger tapping, children with CP often exhibit unintended motions in the nontapping hand, known as mirror motions, which confuse the interpretation of resulting fNIRS images. This work presents a method for separating some of the mirror motion contributions to fNIRS images and demonstrates its application to fNIRS data from four children with CP performing a finger-tapping task with mirror motions. Finger motion and arm muscle activity were measured simultaneously with fNIRS signals using motion tracking and electromyography (EMG), respectively. Subsequently, subject-specific regressors were created from the motion capture or EMG data and independent component analysis was combined with a general linear model to create an fNIRS image representing activation due to the tapping hand and one image representing activation due to the mirror hand. The proposed method can provide information on how mirror motions contribute to fNIRS images, and in some cases, it helps remove mirror motion contamination from the tapping hand activation images.

Motion tracking and electromyography-assisted identification of mirror hand contributions to functional near-infrared spectroscopy images acquired during a finger-tapping task performed by children with cerebral palsy

PubMed Central

Hervey, Nathan; Khan, Bilal; Shagman, Laura; Tian, Fenghua; Delgado, Mauricio R.; Tulchin-Francis, Kirsten; Shierk, Angela; Roberts, Heather; Smith, Linsley; Reid, Dahlia; Clegg, Nancy J.; Liu, Hanli; MacFarlane, Duncan; Alexandrakis, George

2014-01-01

Abstract. Recent studies have demonstrated functional near-infrared spectroscopy (fNIRS) to be a viable and sensitive method for imaging sensorimotor cortex activity in children with cerebral palsy (CP). However, during unilateral finger tapping, children with CP often exhibit unintended motions in the nontapping hand, known as mirror motions, which confuse the interpretation of resulting fNIRS images. This work presents a method for separating some of the mirror motion contributions to fNIRS images and demonstrates its application to fNIRS data from four children with CP performing a finger-tapping task with mirror motions. Finger motion and arm muscle activity were measured simultaneously with fNIRS signals using motion tracking and electromyography (EMG), respectively. Subsequently, subject-specific regressors were created from the motion capture or EMG data and independent component analysis was combined with a general linear model to create an fNIRS image representing activation due to the tapping hand and one image representing activation due to the mirror hand. The proposed method can provide information on how mirror motions contribute to fNIRS images, and in some cases, it helps remove mirror motion contamination from the tapping hand activation images. PMID:26157980

Commentary on the statistical properties of noise and its implication on general linear models in functional near-infrared spectroscopy.

PubMed

Huppert, Theodore J

2016-01-01

Functional near-infrared spectroscopy (fNIRS) is a noninvasive neuroimaging technique that uses low levels of light to measure changes in cerebral blood oxygenation levels. In the majority of NIRS functional brain studies, analysis of this data is based on a statistical comparison of hemodynamic levels between a baseline and task or between multiple task conditions by means of a linear regression model: the so-called general linear model. Although these methods are similar to their implementation in other fields, particularly for functional magnetic resonance imaging, the specific application of these methods in fNIRS research differs in several key ways related to the sources of noise and artifacts unique to fNIRS. In this brief communication, we discuss the application of linear regression models in fNIRS and the modifications needed to generalize these models in order to deal with structured (colored) noise due to systemic physiology and noise heteroscedasticity due to motion artifacts. The objective of this work is to present an overview of these noise properties in the context of the linear model as it applies to fNIRS data. This work is aimed at explaining these mathematical issues to the general fNIRS experimental researcher but is not intended to be a complete mathematical treatment of these concepts.

Rapid Detection of Volatile Oil in Mentha haplocalyx by Near-Infrared Spectroscopy and Chemometrics.

PubMed

Yan, Hui; Guo, Cheng; Shao, Yang; Ouyang, Zhen

2017-01-01

Near-infrared spectroscopy combined with partial least squares regression (PLSR) and support vector machine (SVM) was applied for the rapid determination of chemical component of volatile oil content in Mentha haplocalyx . The effects of data pre-processing methods on the accuracy of the PLSR calibration models were investigated. The performance of the final model was evaluated according to the correlation coefficient ( R ) and root mean square error of prediction (RMSEP). For PLSR model, the best preprocessing method combination was first-order derivative, standard normal variate transformation (SNV), and mean centering, which had of 0.8805, of 0.8719, RMSEC of 0.091, and RMSEP of 0.097, respectively. The wave number variables linking to volatile oil are from 5500 to 4000 cm-1 by analyzing the loading weights and variable importance in projection (VIP) scores. For SVM model, six LVs (less than seven LVs in PLSR model) were adopted in model, and the result was better than PLSR model. The and were 0.9232 and 0.9202, respectively, with RMSEC and RMSEP of 0.084 and 0.082, respectively, which indicated that the predicted values were accurate and reliable. This work demonstrated that near infrared reflectance spectroscopy with chemometrics could be used to rapidly detect the main content volatile oil in M. haplocalyx . The quality of medicine directly links to clinical efficacy, thus, it is important to control the quality of Mentha haplocalyx . Near-infrared spectroscopy combined with partial least squares regression (PLSR) and support vector machine (SVM) was applied for the rapid determination of chemical component of volatile oil content in Mentha haplocalyx . For SVM model, 6 LVs (less than 7 LVs in PLSR model) were adopted in model, and the result was better than PLSR model. It demonstrated that near infrared reflectance spectroscopy with chemometrics could be used to rapidly detect the main content volatile oil in Mentha haplocalyx . Abbreviations used: 1 st der: First-order derivative; 2 nd der: Second-order derivative; LOO: Leave-one-out; LVs: Latent variables; MC: Mean centering, NIR: Near-infrared; NIRS: Near infrared spectroscopy; PCR: Principal component regression, PLSR: Partial least squares regression; RBF: Radial basis function; RMSEC: Root mean square error of cross validation, RMSEC: Root mean square error of calibration; RMSEP: Root mean square error of prediction; SNV: Standard normal variate transformation; SVM: Support vector machine; VIP: Variable Importance in projection.

Rapid assessment of bioactive phenolics and methylxanthines in spent coffee grounds by FT-NIR spectroscopy.

PubMed

Magalhães, Luís M; Machado, Sandia; Segundo, Marcela A; Lopes, João A; Páscoa, Ricardo N M J

2016-01-15

Spent coffee grounds (SCGs) are a great source of bioactive compounds with interest to pharmaceutical and cosmetic industries. Phenolics and methylxanthines are the main health related compounds present in SCG samples. Content estimation of these compounds in SCGs is of upmost importance in what concerns their profitable use by waste recovery industries. In the present work, near-infrared spectroscopy (NIRS) was proposed as a rapid and non-destructive technique to assess the content of three main phenolics (caffeic acid, (+)-catechin and chlorogenic acid) and three methylxanthines (caffeine, theobromine and theophylline) in SCG samples obtained from different coffee brands and diverse coffee machines. The content of these compounds was determined for 61 SCG samples by HPLC coupled with diode-array detection. Partial least squares (PLS) regression based models were calibrated to correlate diffuse reflectance NIR spectra against the reference data for the six parameters obtained by HPLC. Spectral wavelength selection and number of latent variables were optimized by minimizing the cross-validation error. PLS models showed good linearity with a coefficient of determination for the prediction set (Rp(2)) of 0.95, 0.92, 0.88, 071 and 0.84 for caffeine, caffeic acid, (+)-catechin, chlorogenic acid and theophylline, respectively. The range error ratio (RER) was higher for caffeine (17.8) when compared to other compounds (12.0, 10.1, 7.6 and 9.2, respectively for caffeic acid, (+)-catechin, chlorogenic acid and theophylline). Moreover, the content of caffeine could be used to predict the antioxidant properties of SCG samples (R=0.808, n=61), despite not presenting this property itself. The results obtained confirmed that NIRS is a suitable technique to screen SCG samples unveiling those with high content of bioactive compounds, which are interesting for subsequent extraction procedures. Copyright © 2015 Elsevier B.V. All rights reserved.

GNOSIS: The First Fiber Bragg Grating-based OH Suppression Unit

NASA Astrophysics Data System (ADS)

Trinh, Christopher; Ellis, S. C.; Bland-Hawthorn, J.; Lawrence, J. S.; Horton, A. J.; Leon-Saval, S. G.; Shortridge, K.; Bryant, J.; Case, S.; Colless, M.; Couch, W.; Freeman, K. C.; Löhmannsröben, H.; Gers, L.; Glazebrook, K.; Haynes, R.; Lee, S.; O'Byrne, J.; Miziarski, S.; Roth, M. M.; Schmidt, B.; Tinney, C. G.; Zheng, J.

2013-01-01

The sky background is over 1000 times brighter in the near-infrared (NIR) than in the visible placing severe limitations on our ability to study the redshifted light from the distant objects formed in the early Universe from the ground. It is well-known that 98% of the NIR background comes from the forest of bright and highly variable emission lines of atmospheric hydroxyl (OH) molecules. Unfortunately, astronomers have been unable to effectively remove this background from their data. We present the first OH suppression unit, GNOSIS, to utilize fiber Bragg gratings (FBGs). Simple FBGs are optical fibers with a periodic refractive index modulation imprinted within the fiber core, which induces a strong reflection in a narrow 0.2 nm) stopband. GNOSIS utilizes “OH suppression fibers” with a complex aperiodic refractive index modulation capable of removing the 103 brightest OH doublets between 1470 and 1700 nm by up 30 dB before dispersion and in a manner purely dependent on wavelength. The OH suppression fibers have high throughput 60%) and over 90% of the H band is available for spectroscopy. OH suppression units like GNOSIS may be utilized with any NIR telescope and spectrograph combination, but we commissioned GNOSIS at the 3.9-meter Anglo-Australian Telescope with the IRIS2 spectrograph for our first demonstration. Commissioning reveals excellent suppression performance. Approximately 78% of the OH lines were suppressed at the target level or greater. GNOSIS reduces the integrated background between 1500 and 1700 nm by a factor of ~ 9 but the signal-to-noise ratio is about the same as standard long-slit IRIS2 observations due to retrofitting to an un-optimized spectrograph. Nevertheless, if paired with a fiber-optimized spectrograph FBG OH suppression technology shows great promise for high sensitivity NIR spectroscopy at moderate to low resolutions from the ground.

Hemodynamic signals in fNIRS.

PubMed

Hoshi, Y

Near-infrared spectroscopy (NIRS) was originally designed for clinical monitoring of tissue oxygenation, and it has also been developed into a useful tool in neuroimaging studies, with the so-called functional NIRS (fNIRS). With NIRS, cerebral activation is detected by measuring the cerebral hemoglobin (Hb), where however, the precise correlation between NIRS signal and neural activity remains to be fully understood. This can in part be attributed to the situation that NIRS signals are inherently subject to contamination by signals arising from extracerebral tissue. In recent years, several approaches have been investigated to distinguish between NIRS signals originating in cerebral tissue and signals originating in extracerebral tissue. Selective measurements of cerebral Hb will enable a further evolution of fNIRS. This chapter is divided into six sections: first a summary of the basic theory of NIRS, NIRS signals arising in the activated areas, correlations between NIRS signals and fMRI signals, correlations between NIRS signals and neural activities, and the influence of a variety of extracerebral tissue on NIRS signals and approaches to this issue are reviewed. Finally, future prospects of fNIRS are described. © 2016 Elsevier B.V. All rights reserved.

[Research on NIR equivalent spectral measurement].

PubMed

Wang, Zhi-Hong; Liu, Jie; Sun, Yu-Yang; Teng, Fei; Lin, Jun

2013-04-01

When the spectra of the diffuse reflectance of low reflectivity samples or the transmittance of low transmisivity samples are measured by a portable near infrared (NIR) spectrometer, because there is the noise of the spectrometer, the smaller the reflectance or transmittance of the sample, the lower its SNR. Even if treated by denoise methods, the spectra can not meet the requirement of NIR analysis. So the equivalent spectrum measure method was researched. Based on the intensity of the reflected or transmitted signal by the sample under the traditional measure conditions, the light current of the spectrometer was enlarged, and then the signal of the measured sample increased; the reflected or transmitted light of the measure reference was reduced to avoid the signal of the measure reference over range. Moreover the equivalent spectrum of the sample was calculated in order to make it identical with the spectrum measured by traditional method. Thus the NIR spectral SNR was improved. The results of theory analysis and experiments show that if the light signal of the spectrometer was properly increased according to the reflected or transmitted signal of the low reflectivity or transmisivity sample, the equivalent spectrum was the same as the spectrum measured by traditional method and its SNR was improved.

MULTIMODAL IMAGING OF DISEASE-ASSOCIATED PIGMENTARY CHANGES IN RETINITIS PIGMENTOSA.

PubMed

Schuerch, Kaspar; Marsiglia, Marcela; Lee, Winston; Tsang, Stephen H; Sparrow, Janet R

2016-12-01

Using multiple imaging modalities, we evaluated the changes in photoreceptor cells and retinal pigment epithelium (RPE) that are associated with bone spicule-shaped melanin pigmentation in retinitis pigmentosa. In a cohort of 60 patients with retinitis pigmentosa, short-wavelength autofluorescence, near-infrared autofluorescence (NIR-AF), NIR reflectance, spectral domain optical coherence tomography, and color fundus images were studied. Central AF rings were visible in both short-wavelength autofluorescence and NIR-AF images. Bone spicule pigmentation was nonreflective in NIR reflectance, hypoautofluorescent with short-wavelength autofluorescence and NIR-AF imaging, and presented as intraretinal hyperreflective foci in spectral domain optical coherence tomography images. In areas beyond the AF ring outer border, the photoreceptor ellipsoid zone band was absent in spectral domain optical coherence tomography and the visibility of choroidal vessels in short-wavelength autofluorescence, NIR-AF, and NIR reflectance images was indicative of reduced RPE pigmentation. Choroidal visibility was most pronounced in the zone approaching peripheral areas of bone spicule pigmentation; here RPE/Bruch membrane thinning became apparent in spectral domain optical coherence tomography. These findings are consistent with a process by which RPE cells vacate their monolayer and migrate into inner retina in response to photoreceptor cell degeneration. The remaining RPE spread undergo thinning and consequently become less pigmented. An explanation for the absence of NIR-AF melanin signal in relation to bone spicule pigmentation is not forthcoming.

NIR spectroscopic measurement of moisture content in Scots pine seeds.

PubMed

Lestander, Torbjörn A; Geladi, Paul

2003-04-01

When tree seeds are used for seedling production it is important that they are of high quality in order to be viable. One of the factors influencing viability is moisture content and an ideal quality control system should be able to measure this factor quickly for each seed. Seed moisture content within the range 3-34% was determined by near-infrared (NIR) spectroscopy on Scots pine (Pinus sylvestris L.) single seeds and on bulk seed samples consisting of 40-50 seeds. The models for predicting water content from the spectra were made by partial least squares (PLS) and ordinary least squares (OLS) regression. Different conditions were simulated involving both using less wavelengths and going from samples to single seeds. Reflectance and transmission measurements were used. Different spectral pretreatment methods were tested on the spectra. Including bias, the lowest prediction errors for PLS models based on reflectance within 780-2280 nm from bulk samples and single seeds were 0.8% and 1.9%, respectively. Reduction of the single seed reflectance spectrum to 850-1048 nm gave higher biases and prediction errors in the test set. In transmission (850-1048 nm) the prediction error was 2.7% for single seeds. OLS models based on simulated 4-sensor single seed system consisting of optical filters with Gaussian transmission indicated more than 3.4% error in prediction. A practical F-test based on test sets to differentiate models is introduced.

Mid-infrared and near-infrared spectroscopy for rapid detection of Gardeniae Fructus by a liquid-liquid extraction process.

PubMed

Tao, Lingyan; Lin, Zhonglin; Chen, Jiashan; Wu, Yongjiang; Liu, Xuesong

2017-10-25

Gardeniae Fructus is widely used in the pharmaceutical industry, and many studies have confirmed its medical and economic value. In this study, samples collected from different liquid-liquid extraction batches of Gardeniae Fructus were detected by mid-infrared (MIR) and near-infrared (NIR) spectroscopy. Seven analytes, neochlorogenic acid (5-CQA), cryptochlorogenic acid (4-CQA), chlorogenic acid (3-CQA), geniposidic acid (GEA), deacetyl-asperulosidic acid methyl ester (DAAME), genipin-gentiobioside (GGB), and gardenoside (GA), were chosen as quality property indexes of Gardeniae Fructus. The two kinds of spectra were each used to build models by single partial least squares (PLS). Additionally, both spectral data were combined and modeled by multiblock PLS. For single spectroscopy modeling results, NIR had a better prediction for high-concentration analytes (3-CQA, DAAME, GGB, and GA) whereas MIR performed better for low-concentration analytes (5-CQA, 4-CQA, and GEA). The multiblock methodology was found to be better compared to single spectroscopy models for all seven analytes. Specifically, the coefficients of determination (R 2 ) of the NIR, MIR, and multiblock PLS calibration models of all seven components were higher than 0.95. Relative standard errors of prediction (RSEP) were all less than 7%, except for models of GGB, which were 10.36%, 13.24%, and 8.15% for the NIR-PLS, MIR-PLS, and multiblock models, respectively. These results indicate that MIR and NIR spectrographic techniques could provide a new choice for quality control in industrial production of Gardeniae Fructus. Copyright © 2017 Elsevier B.V. All rights reserved.

Remote sensing and the optical properties of the narrow cylindrical leaves of Juncus roemerianus

USGS Publications Warehouse

Ramsey, Elijah W.; Rangoonwala, A.

2004-01-01

To develop a more complete foundation for remote sensing of the marsh grass Juncus roemerianus, we measured the optical properties of its cylindrical leaves at sites of different canopy height, biomass composition and amount, and connectivity to ocean flushing. To measure the leaf optical properties, we adapted a technique used for conifer needles. After establishing the reliability and limits of the adapted technique to the wider J.roemerianus leaves, mean transmittance and reflectance spectra were compared to associated leaf diameters from two dates in 1999 and 2002 and at each site. Transmittance was inversely related to leaf diameter. Mean transmittance and reflectance generated from reoccupation of many field sites in 2002 indicated little or no difference in transmittance between years, a slight reflectance difference in the visible (<2%) and a slightly higher reflectance difference in the near infrared (NIR) (<4%). Site comparison indicated limited ability to separate leaf transmittance but not reflectance by marsh type (e.g., low, medium, high) or biomass. Excluding one outlier, we found leaf transmittances could be adequately represented as 1% ?? 0.2% in the visible and 9% ?? 1% in the NIR and leaf reflectances represented from 14% to 16% in the visible and 71% to 75% in the NIR (the reflectance ranges represent 1999 and 2002 means). Reflectance and transmittance spectra associated with the dead J. roemerianus leaves displayed a spectrally flat increase from the visible to the NIR wavelengths. In total, we documented the atypical optical properties of the cylindrical J. roemerianus leaves and showed that to a first approximation, single means could represent leaf transmittance and visible leaf reflectance across all marsh zones and, after accounting for sample standardization, possibly the NIR reflectance as well.

Within-subject reproducibility of near-infrared spectroscopy signals in sensorimotor activation after 6 months

NASA Astrophysics Data System (ADS)

Sato, Hiroki; Kiguchi, Masashi; Maki, Atsushi; Fuchino, Yutaka; Obata, Akiko; Yoro, Takeshi; Koizumi, Hideaki

2006-01-01

Near-infrared spectroscopy (NIRS) can measure the product of the optical path length and the concentration change in oxygenated hemoglobin (ΔC‧oxy), deoxygenated hemoglobin (ΔC‧deoxy), and their sum (ΔC‧total) in the human cerebral cortex, and it has been used for noninvasive investigation of human brain functions. We evaluate the within-subject reproducibility of the NIRS signals by repeated measurement of the sensorimotor cortex in healthy adults taken over a period of about 6 months using near-infrared (NIR) topography. The maximum signal amplitudes and the location of activation centers are compared between two sessions for each subject. The signal amplitudes vary between sessions and no consistent tendency in the changes is found among subjects. However, the distance between the activation centers identified in two sessions is relatively small, within 20 mm on average across subjects, which is comparable to the smallest distance between measurement positions in the NIR topography (21 mm). Moreover, within-subject comparisons of signal time courses show high correlation coefficients (>0.8) between the two sessions. This result, demonstrating a high within-subject reproducibility of the temporal information in NIRS signals, particularly contributes to the development of a new application of NIRS.

Estimation of Sensory Analysis Cupping Test Arabica Coffee Using NIR Spectroscopy

NASA Astrophysics Data System (ADS)

Safrizal; Sutrisno; Lilik, P. E. N.; Ahmad, U.; Samsudin

2018-05-01

Flavors have become the most important coffee quality parameters now day, many coffee consuming countries require certain taste scores for the coffee to be ordered, the currently used cupping method of appraisal is the method designed by The Specialty Coffee Association Of America (SCAA), from several previous studies was found that Near-Infrared Spectroscopy (NIRS) can be used to detect chemical composition of certain materials including those associated with flavor so it is possible also to be applied to coffee powder. The aim of this research is to get correlation between NIRS spectrum with cupping scoring by tester, then look at the possibility of testing coffee taste sensors using NIRS spectrum. The coffee samples were taken from various places, altitudes and postharvest handling methods, then the samples were prepared following the SCAA protocol, for sensory analysis was done in two ways, with the expert tester and with the NIRS test. The calibration between both found that Without pretreatment using PLS get RMSE cross validation 6.14, using Multiplicative Scatter Correction spectra obtained RMSE cross validation 5.43, the best RMSE cross-validation was 1.73 achieved by de-trending correction, NIRS can be used to predict the score of cupping.

Continuous monitoring of brain dynamics with functional near infrared spectroscopy as a tool for neuroergonomic research: empirical examples and a technological development

PubMed Central

Ayaz, Hasan; Onaral, Banu; Izzetoglu, Kurtulus; Shewokis, Patricia A.; McKendrick, Ryan; Parasuraman, Raja

2013-01-01

Functional near infrared spectroscopy (fNIRS) is a non-invasive, safe, and portable optical neuroimaging method that can be used to assess brain dynamics during skill acquisition and performance of complex work and everyday tasks. In this paper we describe neuroergonomic studies that illustrate the use of fNIRS in the examination of training-related brain dynamics and human performance assessment. We describe results of studies investigating cognitive workload in air traffic controllers, acquisition of dual verbal-spatial working memory skill, and development of expertise in piloting unmanned vehicles. These studies used conventional fNIRS devices in which the participants were tethered to the device while seated at a workstation. Consistent with the aims of mobile brain imaging (MoBI), we also describe a compact and battery-operated wireless fNIRS system that performs with similar accuracy as other established fNIRS devices. Our results indicate that both wired and wireless fNIRS systems allow for the examination of brain function in naturalistic settings, and thus are suitable for reliable human performance monitoring and training assessment. PMID:24385959

Comparative Variable Temperature Studies of Polyamide II with a Benchtop Fourier Transform and a Miniature Handheld Near-Infrared Spectrometer Using 2D-COS and PCMW-2D Analysis.

PubMed

Unger, Miriam; Pfeifer, Frank; Siesler, Heinz W

2016-07-01

The main objective of this communication is to compare the performance of a miniaturized handheld near-infrared (NIR) spectrometer with a benchtop Fourier transform near-infrared (FT-NIR) spectrometer. Generally, NIR spectroscopy is an extremely powerful analytical tool to study hydrogen-bonding changes of amide functionalities in solid and liquid materials and therefore variable temperature NIR measurements of polyamide II (PAII) have been selected as a case study. The information content of the measurement data has been further enhanced by exploiting the potential of two-dimensional correlation spectroscopy (2D-COS) and the perturbation correlation moving window two-dimensional (PCMW2D) evaluation technique. The data provide valuable insights not only into the changes of the hydrogen-bonding structure and the recrystallization of the hydrocarbon segments of the investigated PAII but also in their sequential order. Furthermore, it has been demonstrated that the 2D-COS and PCMW2D results derived from the spectra measured with the miniaturized NIR instrument are equivalent to the information extracted from the data obtained with the high-performance FT-NIR instrument. © The Author(s) 2016.

[Research progress and application prospect of near infrared spectroscopy in soil nutrition analysis].

PubMed

Ding, Hai-quan; Lu, Qi-peng

2012-01-01

"Digital agriculture" or "precision agriculture" is an important direction of modern agriculture technique. It is the combination of the modern information technique and traditional agriculture and becomes a hotspot field in international agriculture research in recent years. As a nondestructive, real-time, effective and exact analysis technique, near infrared spectroscopy, by which precision agriculture could be carried out, has vast prospect in agrology and gradually gained the recognition. The present paper intends to review the basic theory of near infrared spectroscopy and its applications in the field of agrology, pointing out that the direction of NIR in agrology should based on portable NIR spectrograph in order to acquire qualitative or quantitative information from real-time measuring in field. In addition, NIRS could be combined with space remote sensing to macroscopically control the way crop is growing and the nutrition crops need, to change the current state of our country's agriculture radically.

Exploring the Impact of Different Input Data Types on Soil Variable Estimation Using the ICRAF-ISRIC Global Soil Spectral Database.

PubMed

Aitkenhead, Matt J; Black, Helaina I J

2018-02-01

Using the International Centre for Research in Agroforestry-International Soil Reference and Information Centre (ICRAF-ISRIC) global soil spectroscopy database, models were developed to estimate a number of soil variables using different input data types. These input types included: (1) site data only; (2) visible-near-infrared (Vis-NIR) diffuse reflectance spectroscopy only; (3) combined site and Vis-NIR data; (4) red-green-blue (RGB) color data only; and (5) combined site and RGB color data. The models produced variable estimation accuracy, with RGB only being generally worst and spectroscopy plus site being best. However, we showed that for certain variables, estimation accuracy levels achieved with the "site plus RGB input data" were sufficiently good to provide useful estimates (r 2  > 0.7). These included major elements (Ca, Si, Al, Fe), organic carbon, and cation exchange capacity. Estimates for bulk density, contrast-to-noise (C/N), and P were moderately good, but K was not well estimated using this model type. For the "spectra plus site" model, many more variables were well estimated, including many that are important indicators for agricultural productivity and soil health. Sum of cation, electrical conductivity, Si, Ca, and Al oxides, and C/N ratio were estimated using this approach with r 2 values > 0.9. This work provides a mechanism for identifying the cost-effectiveness of using different model input data, with associated costs, for estimating soil variables to required levels of accuracy.

NIR light propagation in a digital head model for traumatic brain injury (TBI)

PubMed Central

Francis, Robert; Khan, Bilal; Alexandrakis, George; Florence, James; MacFarlane, Duncan

2015-01-01

Near infrared spectroscopy (NIRS) is capable of detecting and monitoring acute changes in cerebral blood volume and oxygenation associated with traumatic brain injury (TBI). Wavelength selection, source-detector separation, optode density, and detector sensitivity are key design parameters that determine the imaging depth, chromophore separability, and, ultimately, clinical usefulness of a NIRS instrument. We present simulation results of NIR light propagation in a digital head model as it relates to the ability to detect intracranial hematomas and monitor the peri-hematomal tissue viability. These results inform NIRS instrument design specific to TBI diagnosis and monitoring. PMID:26417498

Optical measurement of cerebral hemodynamics and oxygen metabolism in neonates with congenital heart defects

NASA Astrophysics Data System (ADS)

Durduran, Turgut; Zhou, Chao; Buckley, Erin M.; Kim, Meeri N.; Yu, Guoqiang; Choe, Regine; Gaynor, J. William; Spray, Thomas L.; Durning, Suzanne M.; Mason, Stefanie E.; Montenegro, Lisa M.; Nicolson, Susan C.; Zimmerman, Robert A.; Putt, Mary E.; Wang, Jiongjiong; Greenberg, Joel H.; Detre, John A.; Yodh, Arjun G.; Licht, Daniel J.

2010-05-01

We employ a hybrid diffuse correlation spectroscopy (DCS) and near-infrared spectroscopy (NIRS) monitor for neonates with congenital heart disease (n=33). The NIRS-DCS device measured changes during hypercapnia of oxyhemoglobin, deoxyhemoglobin, and total hemoglobin concentrations; cerebral blood flow (rCBFDCS); and oxygen metabolism (rCMRO2). Concurrent measurements with arterial spin-labeled magnetic resonance imaging (rCBFASL-MRI, n=12) cross-validate rCBFDCS against rCBFASL-MRI, showing good agreement (R=0.7, p=0.01). The study demonstrates use of NIRS-DCS on a critically ill neonatal population, and the results indicate that the optical technology is a promising clinical method for monitoring this population.

[Application of near-infrared spectroscopy to agriculture and food analysis].

PubMed

Wang, Duo-jia; Zhou, Xiang-yang; Jin, Tong-ming; Hu, Xiang-na; Zhong, Jiao-e; Wu, Qi-tang

2004-04-01

Near-Infrared Spectroscopy (NIRS) is the most rapidly developing and the most noticeable spectrographic technique in the 90's (the last century). Its principle and characteristics were explained in this paper, and the development of NIRS instrumentation, the methodology of spectrum pre-processing, as well as the chemical metrology were also introduced. The anthors mainly summarized the applications to agriculture and food, especially in-line analysis methods, which have been used in production procedure by fiber optics. The authors analyzed the NIRS application status in China, and made the first proposal to establish information sharing mode between central database and end-user by using network technology and concentrating valuable resources.

Use telecommunications for real-time process control

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zilberman, I.; Bigman, J.; Sela, I.

1996-05-01

Process operators design real-time accurate information to monitor and control product streams and to optimize unit operations. The challenge is how to cost-effectively install sophisticated analytical equipment in harsh environments such as process areas and maintain system reliability. Incorporating telecommunications technology with near infrared (NIR) spectroscopy may be the bridge to help operations achieve their online control goals. Coupling communications fiber optics with NIR analyzers enables the probe and sampling system to remain in the field and crucial analytical equipment to be remotely located in a general purpose area without specialized protection provisions. The case histories show how two refineriesmore » used NIR spectroscopy online to track octane levels for reformate streams.« less

Reversible near-infrared light directed reflection in a self-organized helical superstructure loaded with upconversion nanoparticles.

PubMed

Wang, Ling; Dong, Hao; Li, Yannian; Xue, Chenming; Sun, Ling-Dong; Yan, Chun-Hua; Li, Quan

2014-03-26

Adding external, dynamic control to self-organized superstructures with desired functionalities is an important leap necessary in leveraging the fascinating molecular systems for applications. Here, the new light-driven chiral molecular switch and upconversion nanoparticles, doped in a liquid crystal media, were able to self-organize into an optically tunable helical superstructure. The resulting nanoparticle impregnated helical superstructure was found to exhibit unprecedented reversible near-infrared (NIR) light-guided tunable behavior only by modulating the excitation power density of a continuous-wave NIR laser (980 nm). Upon irradiation by the NIR laser at the high power density, the reflection wavelength of the photonic superstructure red-shifted, whereas its reverse process occurred upon irradiation by the same laser but with the lower power density. Furthermore, reversible dynamic NIR-light-driven red, green, and blue reflections in a single thin film, achieved only by varying the power density of the NIR light, were for the first time demonstrated.

Application of Functional Near-Infrared Spectroscopy to the Study of Brain Function in Humans and Animal Models

PubMed Central

Kim, Hak Yeong; Seo, Kain; Jeon, Hong Jin; Lee, Unjoo; Lee, Hyosang

2017-01-01

Functional near-infrared spectroscopy (fNIRS) is a noninvasive optical imaging technique that indirectly assesses neuronal activity by measuring changes in oxygenated and deoxygenated hemoglobin in tissues using near-infrared light. fNIRS has been used not only to investigate cortical activity in healthy human subjects and animals but also to reveal abnormalities in brain function in patients suffering from neurological and psychiatric disorders and in animals that exhibit disease conditions. Because of its safety, quietness, resistance to motion artifacts, and portability, fNIRS has become a tool to complement conventional imaging techniques in measuring hemodynamic responses while a subject performs diverse cognitive and behavioral tasks in test settings that are more ecologically relevant and involve social interaction. In this review, we introduce the basic principles of fNIRS and discuss the application of this technique in human and animal studies. PMID:28835022

Quality analysis, classification, and authentication of liquid foods by near-infrared spectroscopy: A review of recent research developments.

PubMed

Wang, Lu; Sun, Da-Wen; Pu, Hongbin; Cheng, Jun-Hu

2017-05-03

Nowadays, near-infrared spectroscopy (NIR) has become one of the most efficient and advanced techniques for analysis of food products. Many relevant researches have been conducted in this regard. However, no reviews about the applications of NIR for liquid food analysis are reported. Therefore, this review summarizes the recent research developments of NIR technology in the field of liquid foods, focusing on the detection of quality attributes of various liquid foods, including alcoholic beverages (red wines, rice wines, and beer), nonalcoholic beverages (juice, fruit vinegars, coffee beverages, and cola beverages), dairy products (milk and yogurt), and oils (vegetable, camellia, peanut, and virgin olive oils and frying oil). In addition, the classification and authentication detection of adulteration are also covered. It is hoped that the current paper can serve as a reference source for the future liquid food analysis by NIR techniques.

Rapid, noninvasive detection of Zika virus in Aedes aegypti mosquitoes by near-infrared spectroscopy.

PubMed

Fernandes, Jill N; Dos Santos, Lílha M B; Chouin-Carneiro, Thaís; Pavan, Márcio G; Garcia, Gabriela A; David, Mariana R; Beier, John C; Dowell, Floyd E; Maciel-de-Freitas, Rafael; Sikulu-Lord, Maggy T

2018-05-01

The accelerating global spread of arboviruses, such as Zika virus (ZIKV), highlights the need for more proactive mosquito surveillance. However, a major challenge during arbovirus outbreaks has been the lack of rapid and affordable tests for pathogen detection in mosquitoes. We show for the first time that near-infrared spectroscopy (NIRS) is a rapid, reagent-free, and cost-effective tool that can be used to noninvasively detect ZIKV in heads and thoraces of intact Aedes aegypti mosquitoes with prediction accuracies of 94.2 to 99.3% relative to quantitative reverse transcription polymerase chain reaction (RT-qPCR). NIRS involves simply shining a beam of light on a mosquito to collect a diagnostic spectrum. We estimated in this study that NIRS is 18 times faster and 110 times cheaper than RT-qPCR. We anticipate that NIRS will be expanded upon for identifying potential arbovirus hotspots to guide the spatial prioritization of vector control.

Hemodynamic signal changes during saliva and water swallowing: a near-infrared spectroscopy study

NASA Astrophysics Data System (ADS)

Kober, Silvia Erika; Wood, Guilherme

2018-01-01

Here, we compared the hemodynamic response observed during swallowing of water or saliva using near-infrared spectroscopy (NIRS). Sixteen healthy adults swallowed water or saliva in a randomized order. Relative concentration changes in oxygenated and deoxygenated hemoglobin during swallowing were assessed. Both swallowing tasks led to the strongest NIRS signal change over the bilateral inferior frontal gyrus. Water swallowing led to a stronger activation over the right hemisphere while the activation focus for saliva swallowing was stronger left lateralized. The NIRS time course also differed between both swallowing tasks especially at the beginning of the tasks, which might be a sign of differences in task effort. Our results show that NIRS is a sensitive measure to reveal differences in the topographical distribution and time course of the hemodynamic response between distinct swallowing tasks and might be therefore an adequate diagnostic and therapy tool for swallowing difficulties.

ASTM clustering for improving coal analysis by near-infrared spectroscopy.

PubMed

Andrés, J M; Bona, M T

2006-11-15

Multivariate analysis techniques have been applied to near-infrared (NIR) spectra coals to investigate the relationship between nine coal properties (moisture (%), ash (%), volatile matter (%), fixed carbon (%), heating value (kcal/kg), carbon (%), hydrogen (%), nitrogen (%) and sulphur (%)) and the corresponding predictor variables. In this work, a whole set of coal samples was grouped into six more homogeneous clusters following the ASTM reference method for classification prior to the application of calibration methods to each coal set. The results obtained showed a considerable improvement of the error determination compared with the calibration for the whole sample set. For some groups, the established calibrations approached the quality required by the ASTM/ISO norms for laboratory analysis. To predict property values for a new coal sample it is necessary the assignation of that sample to its respective group. Thus, the discrimination and classification ability of coal samples by Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) in the NIR range was also studied by applying Soft Independent Modelling of Class Analogy (SIMCA) and Linear Discriminant Analysis (LDA) techniques. Modelling of the groups by SIMCA led to overlapping models that cannot discriminate for unique classification. On the other hand, the application of Linear Discriminant Analysis improved the classification of the samples but not enough to be satisfactory for every group considered.

Monitoring muscle metabolic indexes by time-domain near-infrared spectroscopy during knee flex-extension induced by functional electrical stimulation.

PubMed

Ferrante, Simona; Contini, Davide; Spinelli, Lorenzo; Pedrocchi, Alessandra; Torricelli, Alessandro; Molteni, Franco; Ferrigno, Giancarlo; Cubeddu, Rinaldo

2009-01-01

A noninvasive methodology, combining functional electrical stimulation and time-domain near-infrared spectroscopy (TD-NIRS), is developed to verify whether stroke-altered muscular metabolism on postacute patients. Seven healthy subjects and nine postacute stroke patients undergo a protocol of knee flex-extension induced by quadricep electrical stimulation. During the protocol, TD-NIRS measurements are performed on both rectus femoris to investigate whether significant differences arise between able-bodied and stroke subjects and between patients' paretic and healthy legs. During baseline, metabolic parameters do not show any significant differences among subjects. During stimulation, paretic limbs produce a knee angle significantly lower than healthy legs. During recovery, patients' healthy limbs show a metabolic behavior correlated to able-bodied subjects. Instead, the correlation between the metabolic behavior of the paretic and able-bodied legs allows the definition of two patients' subgroups: one highly correlated (R>0.87) and the other uncorrelated (R<0.08). This grouping reflects the patient functional condition. The results obtained on the most impaired patients suggest that stroke does not produce any systemic consequences at the muscle, but the metabolic dysfunction seems to be local and unilateral. It is crucial to enlarge the sample size of the two subgroups before making these preliminary results a general finding.

Monitoring muscle metabolic indexes by time-domain near-infrared spectroscopy during knee flex-extension induced by functional electrical stimulation

NASA Astrophysics Data System (ADS)

Ferrante, Simona; Contini, Davide; Spinelli, Lorenzo; Pedrocchi, Alessandra; Torricelli, Alessandro; Molteni, Franco; Ferrigno, Giancarlo; Cubeddu, Rinaldo

2009-07-01

A noninvasive methodology, combining functional electrical stimulation and time-domain near-infrared spectroscopy (TD-NIRS), is developed to verify whether stroke-altered muscular metabolism on postacute patients. Seven healthy subjects and nine postacute stroke patients undergo a protocol of knee flex-extension induced by quadricep electrical stimulation. During the protocol, TD-NIRS measurements are performed on both rectus femoris to investigate whether significant differences arise between able-bodied and stroke subjects and between patients' paretic and healthy legs. During baseline, metabolic parameters do not show any significant differences among subjects. During stimulation, paretic limbs produce a knee angle significantly lower than healthy legs. During recovery, patients' healthy limbs show a metabolic behavior correlated to able-bodied subjects. Instead, the correlation between the metabolic behavior of the paretic and able-bodied legs allows the definition of two patients' subgroups: one highly correlated (R>0.87) and the other uncorrelated (R<0.08). This grouping reflects the patient functional condition. The results obtained on the most impaired patients suggest that stroke does not produce any systemic consequences at the muscle, but the metabolic dysfunction seems to be local and unilateral. It is crucial to enlarge the sample size of the two subgroups before making these preliminary results a general finding.

A safe, low-cost, and portable instrumentation for bedside time-resolved picosecond near infrared spectroscopy

NASA Astrophysics Data System (ADS)

Amouroux, Marine; Uhring, Wilfried; Pebayle, Thierry; Poulet, Patrick; Marlier, Luc

2009-07-01

Continuous wave Near InfraRed Spectroscopy (NIRS) has been used successfully in clinical environments for several years to detect cerebral activation thanks to oxymetry (i.e. absorption of photons by oxy- and deoxy- hemoglobin) measurement. The goal of our group is to build a clinically-adapted time-resolved NIRS setup i.e. a setup that is compact and robust enough to allow bedside measurements and that matches safety requirements with human patients applications. Indeed our group has already shown that time resolution allows spatial resolution and improves sensitivity of cerebral activation detection. The setup is built with four laser diodes (excitation wavelengths: 685, 780, 830 and 870 nm) whose emitted light is injected into four optical fibers; detection of reflected photons is made through an avalanche photodiode and a high resolution timing module used to record Temporal Point Spread Functions (TPSF). Validation of the device was made using cylindrically-chaped phantoms with absorbing and/or scattering inclusions. Results show that recorded TPSF are typical both of scattering and absorbing materials thus demonstrating that our apparatus would detect variation of optical properties (absorption and scattering) deep within a diffusive media just like a cerebral activation represents a rise of absorption in the cortex underneath head surface.

Baseline Correction of Diffuse Reflection Near-Infrared Spectra Using Searching Region Standard Normal Variate (SRSNV).

PubMed

Genkawa, Takuma; Shinzawa, Hideyuki; Kato, Hideaki; Ishikawa, Daitaro; Murayama, Kodai; Komiyama, Makoto; Ozaki, Yukihiro

2015-12-01

An alternative baseline correction method for diffuse reflection near-infrared (NIR) spectra, searching region standard normal variate (SRSNV), was proposed. Standard normal variate (SNV) is an effective pretreatment method for baseline correction of diffuse reflection NIR spectra of powder and granular samples; however, its baseline correction performance depends on the NIR region used for SNV calculation. To search for an optimal NIR region for baseline correction using SNV, SRSNV employs moving window partial least squares regression (MWPLSR), and an optimal NIR region is identified based on the root mean square error (RMSE) of cross-validation of the partial least squares regression (PLSR) models with the first latent variable (LV). The performance of SRSNV was evaluated using diffuse reflection NIR spectra of mixture samples consisting of wheat flour and granular glucose (0-100% glucose at 5% intervals). From the obtained NIR spectra of the mixture in the 10 000-4000 cm(-1) region at 4 cm intervals (1501 spectral channels), a series of spectral windows consisting of 80 spectral channels was constructed, and then SNV spectra were calculated for each spectral window. Using these SNV spectra, a series of PLSR models with the first LV for glucose concentration was built. A plot of RMSE versus the spectral window position obtained using the PLSR models revealed that the 8680–8364 cm(-1) region was optimal for baseline correction using SNV. In the SNV spectra calculated using the 8680–8364 cm(-1) region (SRSNV spectra), a remarkable relative intensity change between a band due to wheat flour at 8500 cm(-1) and that due to glucose at 8364 cm(-1) was observed owing to successful baseline correction using SNV. A PLSR model with the first LV based on the SRSNV spectra yielded a determination coefficient (R2) of 0.999 and an RMSE of 0.70%, while a PLSR model with three LVs based on SNV spectra calculated in the full spectral region gave an R2 of 0.995 and an RMSE of 2.29%. Additional evaluation of SRSNV was carried out using diffuse reflection NIR spectra of marzipan and corn samples, and PLSR models based on SRSNV spectra showed good prediction results. These evaluation results indicate that SRSNV is effective in baseline correction of diffuse reflection NIR spectra and provides regression models with good prediction accuracy.

Underwater near-infrared spectroscopy can measure training adaptations in adolescent swimmers

PubMed Central

Parry, Dave; Cooper, Chris E.

2018-01-01

The development of an underwater near-infrared spectroscopy (uNIRS) device has enabled previously unattainable measurements of peripheral muscle hemodynamics and oxygenation to be taken within the natural aquatic environment. The purposes of this study were (i) to trial the use of uNIRS, in a real world training study, and (ii) to monitor the effects of a swim training program upon muscle oxygenation status in short distance swimming. A total of 14 junior club level swimmers completed a repeated swim sprint test before and after an eight week endurance training program. A waterproof, portable Near-Infrared Spectroscopy device was attached to the vastus lateralis. uNIRS successfully measured changes in muscle oxygenation and blood volume in all individuals; rapid sub-second time resolution of the device was able to demonstrate muscle oxygenation changes during the characteristic swim movements. Post training heart rate recovery and swim performance time were significantly improved. uNIRS data also showed significant changes. A larger rise in deoxyhemoglobin during individual sprints suggested training induced an increase in muscle oxygen extraction; a faster recovery time for muscle oxygenation suggested positive training induced changes and significant changes in muscle blood flow also occur. As a strong correlation was seen between an increased reoxygenation rate and an improved swim performance time, these findings support the use of uNIRS as a new performance analysis tool in swimming. PMID:29692951

Underwater near-infrared spectroscopy can measure training adaptations in adolescent swimmers.

PubMed

Jones, Ben; Parry, Dave; Cooper, Chris E

2018-01-01

The development of an underwater near-infrared spectroscopy (uNIRS) device has enabled previously unattainable measurements of peripheral muscle hemodynamics and oxygenation to be taken within the natural aquatic environment. The purposes of this study were (i) to trial the use of uNIRS, in a real world training study, and (ii) to monitor the effects of a swim training program upon muscle oxygenation status in short distance swimming. A total of 14 junior club level swimmers completed a repeated swim sprint test before and after an eight week endurance training program. A waterproof, portable Near-Infrared Spectroscopy device was attached to the vastus lateralis . uNIRS successfully measured changes in muscle oxygenation and blood volume in all individuals; rapid sub-second time resolution of the device was able to demonstrate muscle oxygenation changes during the characteristic swim movements. Post training heart rate recovery and swim performance time were significantly improved. uNIRS data also showed significant changes. A larger rise in deoxyhemoglobin during individual sprints suggested training induced an increase in muscle oxygen extraction; a faster recovery time for muscle oxygenation suggested positive training induced changes and significant changes in muscle blood flow also occur. As a strong correlation was seen between an increased reoxygenation rate and an improved swim performance time, these findings support the use of uNIRS as a new performance analysis tool in swimming.

Determination of alcohol and extract concentration in beer samples using a combined method of near-infrared (NIR) spectroscopy and refractometry.

PubMed

Castritius, Stefan; Kron, Alexander; Schäfer, Thomas; Rädle, Matthias; Harms, Diedrich

2010-12-22

A new approach of combination of near-infrared (NIR) spectroscopy and refractometry was developed in this work to determine the concentration of alcohol and real extract in various beer samples. A partial least-squares (PLS) regression, as multivariate calibration method, was used to evaluate the correlation between the data of spectroscopy/refractometry and alcohol/extract concentration. This multivariate combination of spectroscopy and refractometry enhanced the precision in the determination of alcohol, compared to single spectroscopy measurements, due to the effect of high extract concentration on the spectral data, especially of nonalcoholic beer samples. For NIR calibration, two mathematical pretreatments (first-order derivation and linear baseline correction) were applied to eliminate light scattering effects. A sample grouping of the refractometry data was also applied to increase the accuracy of the determined concentration. The root mean squared errors of validation (RMSEV) of the validation process concerning alcohol and extract concentration were 0.23 Mas% (method A), 0.12 Mas% (method B), and 0.19 Mas% (method C) and 0.11 Mas% (method A), 0.11 Mas% (method B), and 0.11 Mas% (method C), respectively.

NIR spectroscopic sensing for point-of-need freshness assessment of meat, fish, vegetables and fruits

NASA Astrophysics Data System (ADS)

Lee, Seoho; Noh, Tae Gyoon; Choi, Jun Hoe; Han, Jeongsu; Ha, Joo Young; Lee, Ji Young; Park, Yongjong

2017-05-01

Foodborne illness represents a significant health burden worldwide. While monitoring the freshness of food before consumption could significantly improve the current predicament, there is a lack of a simple system that one can use to accurately assess the freshness of their food. Currently, the most common practice for food quality determination is by visual or odor inspection which lacks objectivity, accuracy and precision. Near infrared (NIR) spectroscopic techniques can help address this problem by providing rapid and non-destructive means to estimate the freshness state of various foods based on the changes to their characteristic spectra in the NIR region. Recent advancements in the development of portable NIR spectrometers are also enabling the realization of this technique at the point-of-need. In this study, we have evaluated the feasibility of using NIR spectroscopy at the point-of-need to estimate the freshness of various foods including: beef sirloin, beef eyeround, pork sirloin, bass, salmon, corvina, tomato and watermelon. Using a commercial portable NIR spectrometer, we periodically scanned and collected NIR spectra from the food items that were stored at 4°C inside a refrigerator for up to 30 days. For these food items, we show that the NIR spectra can be classified by the foods' aging day as well as by the levels of chemical/microbial indicators (i.e., thiobarbituric acid, volatile basic nitrogen and bacteria levels) with high accuracy, which represents high prospects of NIR spectroscopy for point-of-need freshness assessment of meat, fish, vegetables and fruits.

Continuous monitoring of kidney transplant perfusion with near-infrared spectroscopy.

PubMed

Malakasioti, Georgia; Marks, Stephen D; Watson, Tom; Williams, Fariba; Taylor-Allkins, Mariesa; Mamode, Nizam; Morgan, Justin; Hayes, Wesley N

2018-05-11

Current reliance on clinical, laboratory and Doppler ultrasound (DUS) parameters for monitoring kidney transplant perfusion in the immediate post-operative period in children risks late recognition of allograft hypoperfusion and vascular complications. Near-infrared spectroscopy (NIRS) is a real-time, non-invasive technique for monitoring tissue oxygenation percutaneously. NIRS monitoring of kidney transplant perfusion has not previously been validated to the gold standard of DUS. We examined whether NIRS tissue oxygenation indices can reliably assess blood flow in established paediatric kidney transplants. Paediatric kidney transplant recipients ages 1-18 years with stable allograft function were eligible. Participants underwent routine DUS assessment of kidney transplant perfusion, including resistive index (RI) and peak systolic velocity at the upper and lower poles. NIRS data [tissue oxygenation index (TOI%)] were recorded for a minimum of 2 min with NIRS sensors placed on the skin over upper and lower allograft poles. Twenty-nine subjects with a median age of 13.3 (range 4.8-17.8) years and a median transplant vintage of 26.5 months participated. Thirteen (45%) were female and 20 (69%) were living donor kidney recipients. NIRS monitoring was well tolerated by all, with 96-100% valid measurements. Significant negative correlations were observed between NIRS TOI% and DUS RI at both the upper and lower poles (r = -0.4 and -0.6, P = 0.04 and 0.001, respectively). Systolic blood pressure but not estimated glomerular filtration rate also correlated with NIRS TOI% (P = 0.01). NIRS indices correlate well with DUS perfusion and haemodynamic parameters in established paediatric kidney transplant recipients. Further studies are warranted to extend NIRS use for continuous real-time monitoring of early post-transplant perfusion status.

In vivo real time non invasive monitoring of brain penetration of chemicals with near-infrared spectroscopy: Concomitant PK/PD analysis.

PubMed

Crespi, Francesco; Cattini, Stefano; Donini, Maurizio; Bandera, Andrea; Rovati, Luigi

2016-01-30

Near-infrared spectroscopy (NIRS) is a non-invasive technique that monitors changes in oxygenation of haemoglobin. The absorption spectra of near-infrared light differ for the oxygenation-deoxygenation states of haemoglobin (oxygenate (HbO2) and deoxygenate (Hb), respectively) so that these two states can be directly monitored. Different methodologies report different basal values of HbO2 and Hb absolute concentrations in brain. Here, we attempt to calculate basal HbO2 levels in rat CNS via evaluation of the influence of exogenous oxygen or exogenous carbon dioxide on the NIRS parameters measured in vivo. Furthermore the possibility that changes of haemoglobin oxygenation in rat brain as measured by NIRS might be a useful index of brain penetration of chemical entities has been investigated. Different compounds from different chemical classes were selected on the basis of parallel ex vivo and in vivo pharmacokinetic (PK/PD) studies of brain penetration and overall pharmacokinetic profile. It appeared that NIRS might contribute to assess brain penetration of chemical entities, i.e. significant changes in NIRS signals could be related to brain exposure, conversely the lack of significant changes in relevant NIRS parameters could be indicative of low brain exposure. This work is proposing a further innovation on NIRS preclinical applications i.e. a "chemical" NIRS [chNIRS] approach for determining penetration of drugs in animal brain. Therefore, chNIRS could became a non invasive methodology for studies on neurobiological processes and psychiatric diseases in preclinical but also a translational strategy from preclinical to clinical investigations. Copyright © 2015 Elsevier B.V. All rights reserved.

Measuring speaker–listener neural coupling with functional near infrared spectroscopy

PubMed Central

Liu, Yichuan; Piazza, Elise A.; Simony, Erez; Shewokis, Patricia A.; Onaral, Banu; Hasson, Uri; Ayaz, Hasan

2017-01-01

The present study investigates brain-to-brain coupling, defined as inter-subject correlations in the hemodynamic response, during natural verbal communication. We used functional near-infrared spectroscopy (fNIRS) to record brain activity of 3 speakers telling stories and 15 listeners comprehending audio recordings of these stories. Listeners’ brain activity was significantly correlated with speakers’ with a delay. This between-brain correlation disappeared when verbal communication failed. We further compared the fNIRS and functional Magnetic Resonance Imaging (fMRI) recordings of listeners comprehending the same story and found a significant relationship between the fNIRS oxygenated-hemoglobin concentration changes and the fMRI BOLD in brain areas associated with speech comprehension. This correlation between fNIRS and fMRI was only present when data from the same story were compared between the two modalities and vanished when data from different stories were compared; this cross-modality consistency further highlights the reliability of the spatiotemporal brain activation pattern as a measure of story comprehension. Our findings suggest that fNIRS can be used for investigating brain-to-brain coupling during verbal communication in natural settings. PMID:28240295

Rapid quantification of multi-components in alcohol precipitation liquid of Codonopsis Radix using near infrared spectroscopy (NIRS).

PubMed

Luo, Yu; Li, Wen-Long; Huang, Wen-Hua; Liu, Xue-Hua; Song, Yan-Gang; Qu, Hai-Bin

2017-05-01

A near infrared spectroscopy (NIRS) approach was established for quality control of the alcohol precipitation liquid in the manufacture of Codonopsis Radix. By applying NIRS with multivariate analysis, it was possible to build variation into the calibration sample set, and the Plackett-Burman design, Box-Behnken design, and a concentrating-diluting method were used to obtain the sample set covered with sufficient fluctuation of process parameters and extended concentration information. NIR data were calibrated to predict the four quality indicators using partial least squares regression (PLSR). In the four calibration models, the root mean squares errors of prediction (RMSEPs) were 1.22 μg/ml, 10.5 μg/ml, 1.43 μg/ml, and 0.433% for lobetyolin, total flavonoids, pigments, and total solid contents, respectively. The results indicated that multi-components quantification of the alcohol precipitation liquid of Codonopsis Radix could be achieved with an NIRS-based method, which offers a useful tool for real-time release testing (RTRT) of intermediates in the manufacture of Codonopsis Radix.

Quantitative Determination of Fluorine Content in Blends of Polylactide (PLA)–Talc Using Near Infrared Spectroscopy

PubMed Central

Tamburini, Elena; Tagliati, Chiara; Bonato, Tiziano; Costa, Stefania; Scapoli, Chiara; Pedrini, Paola

2016-01-01

Near-infrared spectroscopy (NIRS) has been widely used for quantitative and/or qualitative determination of a wide range of matrices. The objective of this study was to develop a NIRS method for the quantitative determination of fluorine content in polylactide (PLA)-talc blends. A blending profile was obtained by mixing different amounts of PLA granules and talc powder. The calibration model was built correlating wet chemical data (alkali digestion method) and NIR spectra. Using FT (Fourier Transform)-NIR technique, a Partial Least Squares (PLS) regression model was set-up, in a concentration interval of 0 ppm of pure PLA to 800 ppm of pure talc. Fluorine content prediction (R2cal = 0.9498; standard error of calibration, SEC = 34.77; standard error of cross-validation, SECV = 46.94) was then externally validated by means of a further 15 independent samples (R2EX.V = 0.8955; root mean standard error of prediction, RMSEP = 61.08). A positive relationship between an inorganic component as fluorine and NIR signal has been evidenced, and used to obtain quantitative analytical information from the spectra. PMID:27490548

Wearable functional near infrared spectroscopy (fNIRS) and transcranial direct current stimulation (tDCS): expanding vistas for neurocognitive augmentation

PubMed Central

McKendrick, Ryan; Parasuraman, Raja; Ayaz, Hasan

2015-01-01

Contemporary studies with transcranial direct current stimulation (tDCS) provide a growing base of evidence for enhancing cognition through the non-invasive delivery of weak electric currents to the brain. The main effect of tDCS is to modulate cortical excitability depending on the polarity of the applied current. However, the underlying mechanism of neuromodulation is not well understood. A new generation of functional near infrared spectroscopy (fNIRS) systems is described that are miniaturized, portable, and include wearable sensors. These developments provide an opportunity to couple fNIRS with tDCS, consistent with a neuroergonomics approach for joint neuroimaging and neurostimulation investigations of cognition in complex tasks and in naturalistic conditions. The effects of tDCS on complex task performance and the use of fNIRS for monitoring cognitive workload during task performance are described. Also explained is how fNIRS + tDCS can be used simultaneously for assessing spatial working memory. Mobile optical brain imaging is a promising neuroimaging tool that has the potential to complement tDCS for realistic applications in natural settings. PMID:25805976

Cortical Signal Analysis and Advances in Functional Near-Infrared Spectroscopy Signal: A Review.

PubMed

Kamran, Muhammad A; Mannan, Malik M Naeem; Jeong, Myung Yung

2016-01-01

Functional near-infrared spectroscopy (fNIRS) is a non-invasive neuroimaging modality that measures the concentration changes of oxy-hemoglobin (HbO) and de-oxy hemoglobin (HbR) at the same time. It is an emerging cortical imaging modality with a good temporal resolution that is acceptable for brain-computer interface applications. Researchers have developed several methods in last two decades to extract the neuronal activation related waveform from the observed fNIRS time series. But still there is no standard method for analysis of fNIRS data. This article presents a brief review of existing methodologies to model and analyze the activation signal. The purpose of this review article is to give a general overview of variety of existing methodologies to extract useful information from measured fNIRS data including pre-processing steps, effects of differential path length factor (DPF), variations and attributes of hemodynamic response function (HRF), extraction of evoked response, removal of physiological noises, instrumentation, and environmental noises and resting/activation state functional connectivity. Finally, the challenges in the analysis of fNIRS signal are summarized.

Cortical Signal Analysis and Advances in Functional Near-Infrared Spectroscopy Signal: A Review

PubMed Central

Kamran, Muhammad A.; Mannan, Malik M. Naeem; Jeong, Myung Yung

2016-01-01

Functional near-infrared spectroscopy (fNIRS) is a non-invasive neuroimaging modality that measures the concentration changes of oxy-hemoglobin (HbO) and de-oxy hemoglobin (HbR) at the same time. It is an emerging cortical imaging modality with a good temporal resolution that is acceptable for brain-computer interface applications. Researchers have developed several methods in last two decades to extract the neuronal activation related waveform from the observed fNIRS time series. But still there is no standard method for analysis of fNIRS data. This article presents a brief review of existing methodologies to model and analyze the activation signal. The purpose of this review article is to give a general overview of variety of existing methodologies to extract useful information from measured fNIRS data including pre-processing steps, effects of differential path length factor (DPF), variations and attributes of hemodynamic response function (HRF), extraction of evoked response, removal of physiological noises, instrumentation, and environmental noises and resting/activation state functional connectivity. Finally, the challenges in the analysis of fNIRS signal are summarized. PMID:27375458

Quality evaluation of frozen guava and yellow passion fruit pulps by NIR spectroscopy and chemometrics.

PubMed

Alamar, Priscila D; Caramês, Elem T S; Poppi, Ronei J; Pallone, Juliana A L

2016-07-01

The present study investigated the application of near infrared spectroscopy as a green, quick, and efficient alternative to analytical methods currently used to evaluate the quality (moisture, total sugars, acidity, soluble solids, pH and ascorbic acid) of frozen guava and passion fruit pulps. Fifty samples were analyzed by near infrared spectroscopy (NIR) and reference methods. Partial least square regression (PLSR) was used to develop calibration models to relate the NIR spectra and the reference values. Reference methods indicated adulteration by water addition in 58% of guava pulp samples and 44% of yellow passion fruit pulp samples. The PLS models produced lower values of root mean squares error of calibration (RMSEC), root mean squares error of prediction (RMSEP), and coefficient of determination above 0.7. Moisture and total sugars presented the best calibration models (RMSEP of 0.240 and 0.269, respectively, for guava pulp; RMSEP of 0.401 and 0.413, respectively, for passion fruit pulp) which enables the application of these models to determine adulteration in guava and yellow passion fruit pulp by water or sugar addition. The models constructed for calibration of quality parameters of frozen fruit pulps in this study indicate that NIR spectroscopy coupled with the multivariate calibration technique could be applied to determine the quality of guava and yellow passion fruit pulp. Copyright © 2016 Elsevier Ltd. All rights reserved.

Investigation of the composition of anabolic tablets using near infrared spectroscopy and Raman chemical imaging.

PubMed

Rebiere, Hervé; Ghyselinck, Céline; Lempereur, Laurent; Brenier, Charlotte

2016-01-01

The use of performance enhancing drugs is a widespread phenomenon in professional and leisure sports. A spectroscopic study was carried out on anabolic tablets labelled as 5 mg methandienone tablets provided by police departments. The analytical approach was based on a two-step methodology: a fast analysis of tablets using near infrared (NIR) spectroscopy to assess sample homogeneity based on their global composition, followed by Raman chemical imaging of one sample per NIR profile to obtain information on sample formulation. NIR spectroscopy assisted by a principal components analysis (PCA) enabled fast discrimination of different profiles based on the excipient formulation. Raman hyperspectral imaging and multivariate curve resolution - alternating least square (MCR-ALS) provided chemical images of the distribution of the active substance and excipients within tablets and facilitated identification of the active compounds. The combination of NIR spectroscopy and Raman chemical imaging highlighted dose-to-dose variations and succeeded in the discrimination of four different formulations out of eight similar samples of anabolic tablets. Some samples contained either methandienone or methyltestosterone whereas one sample did not contain an active substance. Other ingredients were sucrose, lactose, starch or talc. Both techniques were fast and non-destructive and therefore can be carried out as exploratory methods prior to destructive screening methods. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Quantifying the cerebral metabolic rate of oxygen by combining diffuse correlation spectroscopy and time-resolved near-infrared spectroscopy.

PubMed

Verdecchia, Kyle; Diop, Mamadou; Lee, Ting-Yim; St Lawrence, Keith

2013-02-01

Preterm infants are highly susceptible to ischemic brain injury; consequently, continuous bedside monitoring to detect ischemia before irreversible damage occurs would improve patient outcome. In addition to monitoring cerebral blood flow (CBF), assessing the cerebral metabolic rate of oxygen (CMRO2) would be beneficial considering that metabolic thresholds can be used to evaluate tissue viability. The purpose of this study was to demonstrate that changes in absolute CMRO2 could be measured by combining diffuse correlation spectroscopy (DCS) with time-resolved near-infrared spectroscopy (TR-NIRS). Absolute CBF was determined using bolus-tracking TR-NIRS to calibrate the DCS measurements. Cerebral venous blood oxygenation (SvO2) was determined by multiwavelength TR-NIRS measurements, the accuracy of which was assessed by directly measuring the oxygenation of sagittal sinus blood. In eight newborn piglets, CMRO2 was manipulated by varying the anesthetics and by injecting sodium cyanide. No significant differences were found between the two sets of SvO2 measurements obtained by TR-NIRS or sagittal sinus blood samples and the corresponding CMRO2 measurements. Bland-Altman analysis showed a mean CMRO2 difference of 0.0268 ± 0.8340 mLO2/100 g/min between the two techniques over a range from 0.3 to 4 mL O2/100 g/min.

Measurement of process variables in solid-state fermentation of wheat straw using FT-NIR spectroscopy and synergy interval PLS algorithm.

PubMed

Jiang, Hui; Liu, Guohai; Mei, Congli; Yu, Shuang; Xiao, Xiahong; Ding, Yuhan

2012-11-01

The feasibility of rapid determination of the process variables (i.e. pH and moisture content) in solid-state fermentation (SSF) of wheat straw using Fourier transform near infrared (FT-NIR) spectroscopy was studied. Synergy interval partial least squares (siPLS) algorithm was implemented to calibrate regression model. The number of PLS factors and the number of subintervals were optimized simultaneously by cross-validation. The performance of the prediction model was evaluated according to the root mean square error of cross-validation (RMSECV), the root mean square error of prediction (RMSEP) and the correlation coefficient (R). The measurement results of the optimal model were obtained as follows: RMSECV=0.0776, R(c)=0.9777, RMSEP=0.0963, and R(p)=0.9686 for pH model; RMSECV=1.3544% w/w, R(c)=0.8871, RMSEP=1.4946% w/w, and R(p)=0.8684 for moisture content model. Finally, compared with classic PLS and iPLS models, the siPLS model revealed its superior performance. The overall results demonstrate that FT-NIR spectroscopy combined with siPLS algorithm can be used to measure process variables in solid-state fermentation of wheat straw, and NIR spectroscopy technique has a potential to be utilized in SSF industry. Copyright © 2012 Elsevier B.V. All rights reserved.

Quantifying the cerebral metabolic rate of oxygen by combining diffuse correlation spectroscopy and time-resolved near-infrared spectroscopy

NASA Astrophysics Data System (ADS)

Verdecchia, Kyle; Diop, Mamadou; Lee, Ting-Yim; St. Lawrence, Keith

2013-02-01

Preterm infants are highly susceptible to ischemic brain injury; consequently, continuous bedside monitoring to detect ischemia before irreversible damage occurs would improve patient outcome. In addition to monitoring cerebral blood flow (CBF), assessing the cerebral metabolic rate of oxygen (CMRO2) would be beneficial considering that metabolic thresholds can be used to evaluate tissue viability. The purpose of this study was to demonstrate that changes in absolute CMRO2 could be measured by combining diffuse correlation spectroscopy (DCS) with time-resolved near-infrared spectroscopy (TR-NIRS). Absolute CBF was determined using bolus-tracking TR-NIRS to calibrate the DCS measurements. Cerebral venous blood oxygenation (SvO2) was determined by multiwavelength TR-NIRS measurements, the accuracy of which was assessed by directly measuring the oxygenation of sagittal sinus blood. In eight newborn piglets, CMRO2 was manipulated by varying the anesthetics and by injecting sodium cyanide. No significant differences were found between the two sets of SvO2 measurements obtained by TR-NIRS or sagittal sinus blood samples and the corresponding CMRO2 measurements. Bland-Altman analysis showed a mean CMRO2 difference of 0.0268±0.8340 mL O2/100 g/min between the two techniques over a range from 0.3 to 4 mL O2/100 g/min.

Effect of Co and Pr doping on the properties of solar-reflective ZnFe2O4 dark pigment

NASA Astrophysics Data System (ADS)

Suwan, M.; Sangwong, N.; Supothina, S.

2017-03-01

High NIR-reflective Co-doped ZnFe2O4 black pigments were synthesized by a simple solid-state reaction of ZnO and Fe2O3 in the presence of 3 to 30 wt.% Co3O4 at 1000 and 1100 °C. A series of black pigments with low L* values in a range of 25.5-26.5 and NIR reflectance of 39.5-48.7% were obtained at 1000 °C while the pigments with comparable L* values and slightly lower NIR reflectance were obtained at 1100 °C. A change of the pigment property could be attributed to substitution of Co2+ for Zn2+ as revealed by XRD analysis as well as reflectance spectra. Calcination of ZnO and Fe2O3 in the presence of 3 to 30 wt.% Pr6O11 at 1100 °C resulted in dark brown composite pigments consisting of ZnFe2O4, PrFe2O3 and unreacted Fe2O3 with L* value around 40 ±1 and NIR reflectance in a range of 48-50%.

Spectroscopic diagnosis of laryngeal carcinoma using near-infrared Raman spectroscopy and random recursive partitioning ensemble techniques.

PubMed

Teh, Seng Khoon; Zheng, Wei; Lau, David P; Huang, Zhiwei

2009-06-01

In this work, we evaluated the diagnostic ability of near-infrared (NIR) Raman spectroscopy associated with the ensemble recursive partitioning algorithm based on random forests for identifying cancer from normal tissue in the larynx. A rapid-acquisition NIR Raman system was utilized for tissue Raman measurements at 785 nm excitation, and 50 human laryngeal tissue specimens (20 normal; 30 malignant tumors) were used for NIR Raman studies. The random forests method was introduced to develop effective diagnostic algorithms for classification of Raman spectra of different laryngeal tissues. High-quality Raman spectra in the range of 800-1800 cm(-1) can be acquired from laryngeal tissue within 5 seconds. Raman spectra differed significantly between normal and malignant laryngeal tissues. Classification results obtained from the random forests algorithm on tissue Raman spectra yielded a diagnostic sensitivity of 88.0% and specificity of 91.4% for laryngeal malignancy identification. The random forests technique also provided variables importance that facilitates correlation of significant Raman spectral features with cancer transformation. This study shows that NIR Raman spectroscopy in conjunction with random forests algorithm has a great potential for the rapid diagnosis and detection of malignant tumors in the larynx.

Prediction of ethanol in bottled Chinese rice wine by NIR spectroscopy

NASA Astrophysics Data System (ADS)

Ying, Yibin; Yu, Haiyan; Pan, Xingxiang; Lin, Tao

2006-10-01

To evaluate the applicability of non-invasive visible and near infrared (VIS-NIR) spectroscopy for determining ethanol concentration of Chinese rice wine in square brown glass bottle, transmission spectra of 100 bottled Chinese rice wine samples were collected in the spectral range of 350-1200 nm. Statistical equations were established between the reference data and VIS-NIR spectra by partial least squares (PLS) regression method. Performance of three kinds of mathematical treatment of spectra (original spectra, first derivative spectra and second derivative spectra) were also discussed. The PLS models of original spectra turned out better results, with higher correlation coefficient in calibration (R cal) of 0.89, lower root mean standard error of calibration (RMSEC) of 0.165, and lower root mean standard error of cross validation (RMSECV) of 0.179. Using original spectra, PLS models for ethanol concentration prediction were developed. The R cal and the correlation coefficient in validation (R val) were 0.928 and 0.875, respectively; and the RMSEC and the root mean standard error of validation (RMSEP) were 0.135 (%, v v -1) and 0.177 (%, v v -1), respectively. The results demonstrated that VIS-NIR spectroscopy could be used to predict ethanol concentration in bottled Chinese rice wine.

Development and Testing of an LED-Based Near-Infrared Sensor for Human Kidney Tumor Diagnostics

PubMed Central

Zabarylo, Urszula; Kirsanov, Dmitry; Belikova, Valeria; Ageev, Vladimir; Usenov, Iskander; Galyanin, Vladislav; Minet, Olaf; Sakharova, Tatiana; Danielyan, Georgy; Feliksberger, Elena; Artyushenko, Viacheslav

2017-01-01

Optical spectroscopy is increasingly used for cancer diagnostics. Tumor detection feasibility in human kidney samples using mid- and near-infrared (NIR) spectroscopy, fluorescence spectroscopy, and Raman spectroscopy has been reported (Artyushenko et al., Spectral fiber sensors for cancer diagnostics in vitro. In Proceedings of the European Conference on Biomedical Optics, Munich, Germany, 21–25 June 2015). In the present work, a simplification of the NIR spectroscopic analysis for cancer diagnostics was studied. The conventional high-resolution NIR spectroscopic method of kidney tumor diagnostics was replaced by a compact optical sensing device constructively represented by a set of four light-emitting diodes (LEDs) at selected wavelengths and one detecting photodiode. Two sensor prototypes were tested using 14 in vitro clinical samples of 7 different patients. Statistical data evaluation using principal component analysis (PCA) and partial least-squares discriminant analysis (PLS-DA) confirmed the general applicability of the LED-based sensing approach to kidney tumor detection. An additional validation of the results was performed by means of sample permutation. PMID:28825612

Variety identification of brown sugar using short-wave near infrared spectroscopy and multivariate calibration

NASA Astrophysics Data System (ADS)

Yang, Haiqing; Wu, Di; He, Yong

2007-11-01

Near-infrared spectroscopy (NIRS) with the characteristics of high speed, non-destructiveness, high precision and reliable detection data, etc. is a pollution-free, rapid, quantitative and qualitative analysis method. A new approach for variety discrimination of brown sugars using short-wave NIR spectroscopy (800-1050nm) was developed in this work. The relationship between the absorbance spectra and brown sugar varieties was established. The spectral data were compressed by the principal component analysis (PCA). The resulting features can be visualized in principal component (PC) space, which can lead to discovery of structures correlative with the different class of spectral samples. It appears to provide a reasonable variety clustering of brown sugars. The 2-D PCs plot obtained using the first two PCs can be used for the pattern recognition. Least-squares support vector machines (LS-SVM) was applied to solve the multivariate calibration problems in a relatively fast way. The work has shown that short-wave NIR spectroscopy technique is available for the brand identification of brown sugar, and LS-SVM has the better identification ability than PLS when the calibration set is small.

Multi-parameters monitoring during traditional Chinese medicine concentration process with near infrared spectroscopy and chemometrics

NASA Astrophysics Data System (ADS)

Liu, Ronghua; Sun, Qiaofeng; Hu, Tian; Li, Lian; Nie, Lei; Wang, Jiayue; Zhou, Wanhui; Zang, Hengchang

2018-03-01

As a powerful process analytical technology (PAT) tool, near infrared (NIR) spectroscopy has been widely used in real-time monitoring. In this study, NIR spectroscopy was applied to monitor multi-parameters of traditional Chinese medicine (TCM) Shenzhiling oral liquid during the concentration process to guarantee the quality of products. Five lab scale batches were employed to construct quantitative models to determine five chemical ingredients and physical change (samples density) during concentration process. The paeoniflorin, albiflorin, liquiritin and samples density were modeled by partial least square regression (PLSR), while the content of the glycyrrhizic acid and cinnamic acid were modeled by support vector machine regression (SVMR). Standard normal variate (SNV) and/or Savitzkye-Golay (SG) smoothing with derivative methods were adopted for spectra pretreatment. Variable selection methods including correlation coefficient (CC), competitive adaptive reweighted sampling (CARS) and interval partial least squares regression (iPLS) were performed for optimizing the models. The results indicated that NIR spectroscopy was an effective tool to successfully monitoring the concentration process of Shenzhiling oral liquid.

Breast tumor characterization using near-infrared spectroscopy

NASA Astrophysics Data System (ADS)

Kang, Kyung A.; Chance, Britton; Zhao, Shiyin; Srinivasan, Sudhakar; Patterson, E.; Troupin, R.

1993-09-01

NIR time resolved spectroscopy (TRS) is one of the most feasible methods which can be used for the characterization of biological systems, due to its non-invasive nature and safety features in measurement. Breast cancer is the leading cause of death in women ages 40 - 44 and accounts for 32% of all cancer diagnosis in women. The occurrence rate is as high as one out of nine women in the USA. Breast cancer is the most common form of cancer and the second leading cause of cancer death in North America. Therefore, it is natural for researchers in the field of NIR spectroscopy to have strong interest in optical properties of normal and abnormal breast tissue. One of the main interests of NIR spectroscopy in breast cancer is the localization of the tumor. Another important feature is to characterize an anomaly non- invasively since more than 75% of mammographical anomalies are found to be benign. This could reduce the anxiety that the patients would have, as well as lower the clinical expense for the biopsy and operation (approximately $4,000 per a case).

An Improved Weighted Partial Least Squares Method Coupled with Near Infrared Spectroscopy for Rapid Determination of Multiple Components and Anti-Oxidant Activity of Pu-Erh Tea.

PubMed

Liu, Ze; Xie, Hua-Lin; Chen, Lin; Huang, Jian-Hua

2018-05-02

Background: Pu-erh tea is a unique microbially fermented tea, which distinctive chemical constituents and activities are worthy of systematic study. Near infrared spectroscopy (NIR) coupled with suitable chemometrics approaches can rapidly and accurately quantitatively analyze multiple compounds in samples. Methods: In this study, an improved weighted partial least squares (PLS) algorithm combined with near infrared spectroscopy (NIR) was used to construct a fast calibration model for determining four main components, i.e., tea polyphenols, tea polysaccharide, total flavonoids, theanine content, and further determine the total antioxidant capacity of pu-erh tea. Results: The final correlation coefficients R square for tea polyphenols, tea polysaccharide, total flavonoids content, theanine content, and total antioxidant capacity were 0.8288, 0.8403, 0.8415, 0.8537 and 0.8682, respectively. Conclusions : The current study provided a comprehensive study of four main ingredients and activity of pu-erh tea, and demonstrated that NIR spectroscopy technology coupled with multivariate calibration analysis could be successfully applied to pu-erh tea quality assessment.

Early detection of emerging street drugs by near infrared spectroscopy and chemometrics.

PubMed

Risoluti, R; Materazzi, S; Gregori, A; Ripani, L

2016-06-01

Near-infrared spectroscopy (NIRs) is spreading as the tool of choice for fast and non-destructive analysis and detection of different compounds in complex matrices. This paper investigated the feasibility of using near infrared (NIR) spectroscopy coupled to chemometrics calibration to detect new psychoactive substances in street samples. The capabilities of this approach in forensic chemistry were assessed in the determination of new molecules appeared in the illicit market and often claimed to contain "non-illegal" compounds, although exhibiting important psychoactive effects. The study focused on synthetic molecules belonging to the classes of synthetic cannabinoids and phenethylamines. The approach was validated comparing results with officials methods and has been successfully applied for "in site" determination of illicit drugs in confiscated real samples, in cooperation with the Scientific Investigation Department (Carabinieri-RIS) of Rome. The achieved results allow to consider NIR spectroscopy analysis followed by chemometrics as a fast, cost-effective and useful tool for the preliminary determination of new psychoactive substances in forensic science. Copyright © 2016 Elsevier B.V. All rights reserved.

Maturation of the cytochrome cd1 nitrite reductase NirS from Pseudomonas aeruginosa requires transient interactions between the three proteins NirS, NirN and NirF

PubMed Central

Nicke, Tristan; Schnitzer, Tobias; Münch, Karin; Adamczack, Julia; Haufschildt, Kristin; Buchmeier, Sabine; Kucklick, Martin; Felgenträger, Undine; Jänsch, Lothar; Riedel, Katharina; Layer, Gunhild

2013-01-01

The periplasmic cytochrome cd1 nitrite reductase NirS occurring in denitrifying bacteria such as the human pathogen Pseudomonas aeruginosa contains the essential tetrapyrrole cofactors haem c and haem d1. Whereas the haem c is incorporated into NirS by the cytochrome c maturation system I, nothing is known about the insertion of the haem d1 into NirS. Here, we show by co-immunoprecipitation that NirS interacts with the potential haem d1 insertion protein NirN in vivo. This NirS–NirN interaction is dependent on the presence of the putative haem d1 biosynthesis enzyme NirF. Further, we show by affinity co-purification that NirS also directly interacts with NirF. Additionally, NirF is shown to be a membrane anchored lipoprotein in P. aeruginosa. Finally, the analysis by UV–visible absorption spectroscopy of the periplasmic protein fractions prepared from the P. aeruginosa WT (wild-type) and a P. aeruginosa ΔnirN mutant shows that the cofactor content of NirS is altered in the absence of NirN. Based on our results, we propose a potential model for the maturation of NirS in which the three proteins NirS, NirN and NirF form a transient, membrane-associated complex in order to achieve the last step of haem d1 biosynthesis and insertion of the cofactor into NirS. PMID:23683062

Estimating Leaf Water Status from Vis-Nir Reflectance and Transmittance

NASA Technical Reports Server (NTRS)

Vanderbilt, Vern; Daughtry, Craig; Dahlgren, Robert

2017-01-01

Remotely sensing the water status of plant canopies remains a long term goal of remote sensing research. Established approaches involve measurements in the thermal infrared and the 900-2000nm reflective infrared. Less popular UV-visible-NIR techniques presumably deserve research attention, because photochemical changes linked to plant water status manifest spectral light scattering and absorption changes. Here we monitored the visible and NIR light reflected from the leaf interior as well as the leaf transmittance as the relative water content of corn (Zeamays L.) leaves decreased. Our results highlight the importance of both scattering effects and effects due to absorption by leaf pigments.

Variation in caffeine concentration in single coffee beans.

PubMed

Fox, Glen P; Wu, Alex; Yiran, Liang; Force, Lesleigh

2013-11-13

Twenty-eight coffee samples from around the world were tested for caffeine levels to develop near-infrared reflectance spectroscopy (NIRS) calibrations for whole and ground coffee. Twenty-five individual beans from five of those coffees were used to develop a NIRS calibration for caffeine concentration in single beans. An international standard high-performance liquid chromatography method was used to analyze for caffeine content. Coffee is a legal stimulant and possesses a number of heath properties. However, there is variation in the level of caffeine in brewed coffee and other caffeinated beverages. Being able to sort beans on the basis of caffeine concentration will improve quality control in the level of caffeine in those beverages. The range in caffeine concentration was from 0.01 mg/g (decaffeinated coffee) to 19.9 mg/g (Italian coffee). The majority of coffees were around 10.0-12.0 mg/g. The NIRS results showed r(2) values for bulk unground and ground coffees were >0.90 with standard errors <2 mg/g. For the single-bean calibration the r(2) values were between 0.85 and 0.93 with standard errors of cross validation of 0.8-1.6 mg/g depending upon calibration. The results showed it was possible to develop NIRS calibrations to estimate the caffeine concentration of individual coffee beans. One application of this calibration could be sorting beans on caffeine concentration to provide greater quality control for high-end markets. Furthermore, bean sorting may open new markets for novel coffee products.

Cerebral oximetry monitoring in the management of severe hypoxaemia associated with transposition of the great arteries with balloon atrial septostomy.

PubMed

Pérez Moreno, J C; Nájera Losada, D C; Sanabria Carretero, P; Paredes Lacave, Á; Benito Bartolomé, F

2018-05-01

Transposition of the great arteries (D-TGA) is one of the most common congenital heart diseases requiring neonatal surgical intervention. In the desperately ill neonate with TGA and the resultant hypoxaemia, acidemia, and congestive heart failure, improvement is often obtained with balloon atrial septostomy (BAS). Current methods employed to evaluate oxygen delivery and tissue consumption are frequently nonspecific. Near infrared spectroscopy (NIRS) allows a continuous non-invasive measurement of tissue oxygenation which reflects perfusion status in real time. Because little is known about the direct effect of BAS on the neonatal brain and on cerebral oxygenation, we measured the effectiveness of BAS in two patients with D-TGA using NIRS before and after BAS. We concluded BAS improves cerebral oxygen saturation in neonates with D-TGA. Copyright © 2017 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.

Parametric models of reflectance spectra for dyed fabrics

NASA Astrophysics Data System (ADS)

Aiken, Daniel C.; Ramsey, Scott; Mayo, Troy; Lambrakos, Samuel G.; Peak, Joseph

2016-05-01

This study examines parametric modeling of NIR reflectivity spectra for dyed fabrics, which provides for both their inverse and direct modeling. The dye considered for prototype analysis is triarylamine dye. The fabrics considered are camouflage textiles characterized by color variations. The results of this study provide validation of the constructed parametric models, within reasonable error tolerances for practical applications, including NIR spectral characteristics in camouflage textiles, for purposes of simulating NIR spectra corresponding to various dye concentrations in host fabrics, and potentially to mixtures of dyes.

Near infrared and Raman spectroscopy as Process Analytical Technology tools for the manufacturing of silicone-based drug reservoirs.

PubMed

Mantanus, J; Rozet, E; Van Butsele, K; De Bleye, C; Ceccato, A; Evrard, B; Hubert, Ph; Ziémons, E

2011-08-05

Using near infrared (NIR) and Raman spectroscopy as PAT tools, 3 critical quality attributes of a silicone-based drug reservoir were studied. First, the Active Pharmaceutical Ingredient (API) homogeneity in the reservoir was evaluated using Raman spectroscopy (mapping): the API distribution within the industrial drug reservoirs was found to be homogeneous while API aggregates were detected in laboratory scale samples manufactured with a non optimal mixing process. Second, the crosslinking process of the reservoirs was monitored at different temperatures with NIR spectroscopy. Conformity tests and Principal Component Analysis (PCA) were performed on the collected data to find out the relation between the temperature and the time necessary to reach the crosslinking endpoints. An agreement was found between the conformity test results and the PCA results. Compared to the conformity test method, PCA had the advantage to discriminate the heating effect from the crosslinking effect occurring together during the monitored process. Therefore the 2 approaches were found to be complementary. Third, based on the HPLC reference method, a NIR model able to quantify the API in the drug reservoir was developed and thoroughly validated. Partial Least Squares (PLS) regression on the calibration set was performed to build prediction models of which the ability to quantify accurately was tested with the external validation set. The 1.2% Root Mean Squared Error of Prediction (RMSEP) of the NIR model indicated the global accuracy of the model. The accuracy profile based on tolerance intervals was used to generate a complete validation report. The 95% tolerance interval calculated on the validation results indicated that each future result will have a relative error below ±5% with a probability of at least 95%. In conclusion, 3 critical quality attributes of silicone-based drug reservoirs were quickly and efficiently evaluated by NIR and Raman spectroscopy. Copyright © 2011 Elsevier B.V. All rights reserved.

Application of near-infrared spectroscopy for estimation of non-structural carbohydrates in foliar samples of Eucalyptus globulus Labilladière.

PubMed

Quentin, A G; Rodemann, T; Doutreleau, M-F; Moreau, M; Davies, N W; Millard, Peter

2017-01-31

Near-infrared reflectance spectroscopy (NIRS) is frequently used for the assessment of key nutrients of forage or crops but remains underused in ecological and physiological studies, especially to quantify non-structural carbohydrates. The aim of this study was to develop calibration models to assess the content in soluble sugars (fructose, glucose, sucrose) and starch in foliar material of Eucalyptus globulus. A partial least squares (PLS) regression was used on the sample spectral data and was compared to the contents measured using standard wet chemistry methods. The calibration models were validated using a completely independent set of samples. We used key indicators such as the ratio of prediction to deviation (RPD) and the range error ratio to give an assessment of the performance of the calibration models. Accurate calibration models were obtained for fructose and sucrose content (R2 > 0.85, root mean square error of prediction (RMSEP) of 0.95%–1.26% in the validation models), followed by sucrose and total soluble sugar content (R2 ~ 0.70 and RMSEP > 2.3%). In comparison to the others, calibration of the starch model performed very poorly with RPD = 1.70. This study establishes the ability of the NIRS calibration model to infer soluble sugar content in foliar samples of E. globulus in a rapid and cost-effective way. We suggest a complete redevelopment of the starch analysis using more specific quantification such as an HPLC-based technique to reach higher performance in the starch model. Overall, NIRS could serve as a high-throughput phenotyping tool to study plant response to stress factors.

Determination of NIR informative wavebands for transmission non-invasive blood glucose measurement using a Fourier transform spectrometer

NASA Astrophysics Data System (ADS)

Yang, Wenming; Liao, Ningfang; Cheng, Haobo; Li, Yasheng; Bai, Xueqiong; Deng, Chengyang

2018-03-01

Non-invasive blood glucose measurement using near infrared (NIR) spectroscopy relies on wavebands that provide reliable information about spectral absorption. In this study, we investigated wavebands which are informative for blood glucose in the NIR shortwave band (900˜1450 nm) and the first overtone band (1450˜1700 nm) through a specially designed NIR Fourier transform spectrometer (FTS), which featured a test fixture (where a sample or subject's finger could be placed) and all-reflective optics, except for a Michelson structure. Different concentrations of glucose solution and seven volunteers who had undergone oral glucose tolerance tests (OGTT) were studied to acquire transmission spectra in the shortwave band and the first overtone band. Characteristic peaks of glucose absorption were identified from the spectra of glucose aqueous solution by second-order derivative processing. The wavebands linked to blood glucose were successfully estimated through spectra of the middle fingertip of OGTT participants by a simple linear regression and correlation coefficient. The light intensity difference showed that glucose absorption in the first overtone band was much more prominent than it was in the shortwave band. The results of the SLR model established from seven OGTTs in total on seven participants enabled a positive estimation of the glucose-linked wavelength. It is suggested that wavebands with prominent characteristic peaks, a high correlation coefficient between blood glucose and light intensity difference and a relatively low standard deviation of predicted values will be the most informative wavebands for transmission non-invasive blood glucose measurement methods. This work provides a guidance for waveband selection for the development of non-invasive NIR blood glucose measurement.

Variable-temperature Fourier transform near-infrared imaging spectroscopy of the deuterium/hydrogen exchange in liquid D₂O.

PubMed

Unger, Miriam; Ozaki, Yukihiro; Siesler, Heinz W

2014-01-01

In the present publication, the deuterium/hydrogen (D/H) exchange of liquid D2O exposed to water vapor of the surrounding atmosphere has been studied by variable-temperature Fourier transform near-infrared (FT-NIR) imaging spectroscopy. Apart from the visualization of the exchange process in the time-resolved FT-NIR images, kinetic parameters and the activation energy for this D/H exchange reaction have been derived from the Arrhenius plot of the variable-temperature spectroscopic data.

Noninvasive in situ identification and band assignments of some pharmaceutical excipients inside USP vials with FT-near-infrared spectroscopy

NASA Astrophysics Data System (ADS)

Ali, Hassan Refat H.; Edwards, Howell G. M.; Scowen, Ian J.

2009-05-01

For the manufacture of dosage forms all ingredients must be reliably identified. In this paper, the suitability of FT-NIR spectroscopy to identify potassium sorbate, sodium starch glycollate, calcium ascorbate, calcium carbonate, candelilla wax, maltosextrin, monohydrated and anhydrous lactose inside USP vials was investigated. Differentiation between the anhydrous and monohydrated forms of lactose was found to be possible by studying the regions of the near-infrared spectrum corresponding to the combination and first overtone stretching frequencies of water. The results show unequivocally the potential of FT-NIR spectroscopy for rapid, in situ and non-destructive identification of pharmaceutical excipients.

Toward Adaptation of fNIRS Instrumentation to Airborne Environments

NASA Technical Reports Server (NTRS)

Adamovsky, Grigory; Mackey, Jeffrey R.

2013-01-01

The paper reviews potential applications of functional Near-Infrared Spectroscopy (fNIRS), a well-known medical diagnostic technique, to monitoring the cognitive state of pilots with a focus on identifying ways to adopt this technique to airborne environments. We also discuss various fNIRS techniques and the direction of technology maturation of associated hardware in view of their potential for miniaturization, maximization of data collection capabilities, and user friendliness.

Toward Adaptation of fNIRS Instrumentation to Airborne Environments

NASA Technical Reports Server (NTRS)

Adamovsky, Grigory; Mackey, Jeffrey; Harrivel, Angela; Hearn, Tristan; Floyd, Bertram

2014-01-01

The paper reviews potential applications of functional Near-Infrared Spectroscopy (fNIRS), a well-known medical diagnostic technique, to monitoring the cognitive state of pilots with a focus on identifying ways to adopt this technique to airborne environments. We also discuss various fNIRS techniques and the direction of technology maturation of associated hardware in view of their potential for miniaturization, maximization of data collection capabilities, and user friendliness.

Test-retest reliability of the prefrontal response to affective pictures based on functional near-infrared spectroscopy

NASA Astrophysics Data System (ADS)

Huang, Yuxia; Mao, Mengchai; Zhang, Zong; Zhou, Hui; Zhao, Yang; Duan, Lian; Kreplin, Ute; Xiao, Xiang; Zhu, Chaozhe

2017-01-01

Functional near-infrared spectroscopy (fNIRS) is being increasingly applied to affective and social neuroscience research; however, the reliability of this method is still unclear. This study aimed to evaluate the test-retest reliability of the fNIRS-based prefrontal response to emotional stimuli. Twenty-six participants viewed unpleasant and neutral pictures, and were simultaneously scanned by fNIRS in two sessions three weeks apart. The reproducibility of the prefrontal activation map was evaluated at three spatial scales (mapwise, clusterwise, and channelwise) at both the group and individual levels. The influence of the time interval was also explored and comparisons were made between longer (intersession) and shorter (intrasession) time intervals. The reliabilities of the activation map at the group level for the mapwise (up to 0.88, the highest value appeared in the intersession assessment) and clusterwise scales (up to 0.91, the highest appeared in the intrasession assessment) were acceptable, indicating that fNIRS may be a reliable tool for emotion studies, especially for a group analysis and under larger spatial scales. However, it should be noted that the individual-level and the channelwise fNIRS prefrontal responses were not sufficiently stable. Future studies should investigate which factors influence reliability, as well as the validity of fNIRS used in emotion studies.

[Applications and prospects of on-line near infrared spectroscopy technology in manufacturing of Chinese materia medica].

PubMed

Li, Yang; Wu, Zhi-Sheng; Pan, Xiao-Ning; Shi, Xin-Yuan; Guo, Ming-Ye; Xu, Bing; Qiao, Yan-Jiang

2014-10-01

The quality of Chinese materia medica (CMM) is affected by every process in CMM manufacturing. According to multi-unit complex features in the production of CMM, on-line near infrared spectroscopy (NIR) is used as an evaluating technology with its rapid, non-destructive and non-pollution etc. advantages. With the research in institutions, the on-line NIR applied in process analysis and control of CMM was described systematically, and the on-line NIR platform building was used as an example to clarify the feasibility of on-line NIR technology in CMM manufacturing process. Then, from the point of application by pharmaceutical companies, the current on-line NIR research on CMM and its production in pharmaceutical companies was relatively comprehensively summarized. Meanwhile, the types of CMM productions were classified in accordance with two formulations (liquid and solid dosage formulations). The different production processes (extraction, concentration and alcohol precipitation, etc. ) were used as liquid formulation diacritical points; the different types (tablets, capsules and plasters, etc.) were used as solid dosage formulation diacritical points, and the reliability of on-line NIR used in the whole process in CMM production was proved in according to the summary of literatures in recent 10 years, which could support the modernization of CMM production.

Do radio frequencies of medical instruments common in the operating room interfere with near-infrared spectroscopy signals?

NASA Astrophysics Data System (ADS)

Shadgan, Babak; Molavi, Behnam; Reid, W. D.; Dumont, Guy; Macnab, Andrew J.

2010-02-01

Background: Medical and diagnostic applications of near infrared spectroscopy (NIRS) are increasing, especially in operating rooms (OR). Since NIRS is an optical technique, radio frequency (RF) interference from other instruments is unlikely to affect the raw optical data, however, NIRS data processing and signal output could be affected. Methods: We investigated the potential for three common OR instruments: an electrical cautery, an orthopaedic drill and an imaging system, to generate electromagnetic interference (EMI) that could potentially influence NIRS signals. The time of onset and duration of every operation of each device was recorded during surgery. To remove the effects of slow changing physiological variables, we first used a lowpass filter and then selected 2 windows with variable lengths around the moment of device onset. For each instant, variances (energy) and means of the signals in the 2 windows were compared. Results: Twenty patients were studied during ankle surgery. Analysis shows no statistically significant difference in the means and variance of the NIRS signals (p < 0.01) during operation of any of the three devices for all surgeries. Conclusion: This method confirms the instruments evaluated caused no significant interference. NIRS can potentially be used without EMI in clinical environments such as the OR.

Diagnostic potential of Raman spectroscopy in Barrett's esophagus

NASA Astrophysics Data System (ADS)

Wong Kee Song, Louis-Michel; Molckovsky, Andrea; Wang, Kenneth K.; Burgart, Lawrence J.; Dolenko, Brion; Somorjai, Rajmund L.; Wilson, Brian C.

2005-04-01

Patients with Barrett's esophagus (BE) undergo periodic endoscopic surveillance with random biopsies in an effort to detect dysplastic or early cancerous lesions. Surveillance may be enhanced by near-infrared Raman spectroscopy (NIRS), which has the potential to identify endoscopically-occult dysplastic lesions within the Barrett's segment and allow for targeted biopsies. The aim of this study was to assess the diagnostic performance of NIRS for identifying dysplastic lesions in BE in vivo. Raman spectra (Pexc=70 mW; t=5 s) were collected from Barrett's mucosa at endoscopy using a custom-built NIRS system (λexc=785 nm) equipped with a filtered fiber-optic probe. Each probed site was biopsied for matching histological diagnosis as assessed by an expert pathologist. Diagnostic algorithms were developed using genetic algorithm-based feature selection and linear discriminant analysis, and classification was performed on all spectra with a bootstrap-based cross-validation scheme. The analysis comprised 192 samples (112 non-dysplastic, 54 low-grade dysplasia and 26 high-grade dysplasia/early adenocarcinoma) from 65 patients. Compared with histology, NIRS differentiated dysplastic from non-dysplastic Barrett's samples with 86% sensitivity, 88% specificity and 87% accuracy. NIRS identified 'high-risk' lesions (high-grade dysplasia/early adenocarcinoma) with 88% sensitivity, 89% specificity and 89% accuracy. In the present study, NIRS classified Barrett's epithelia with high and clinically-useful diagnostic accuracy.

Automated cart with VIS/NIR hyperspectral reflectance and fluorescence imaging capabilities

USDA-ARS?s Scientific Manuscript database

A system to take high-resolution VIS/NIR hyperspectral reflectance and fluorescence images in outdoor fields using ambient lighting or a pulsed laser (355 nm), respectively, for illumination was designed, built, and tested. Components of the system include a semi-autonomous cart, a gated-intensified...

[Achievement of the noninvasive measurement for human blood glucose with NIR diffusion reflectance spectrum method].

PubMed

Zhang, Hong-yan; Ding, Dong; Song, Li-qiang; Gu, Lin-na; Yang, Peng; Tang, Yu-guo

2005-06-01

The noninvasive measurement of human blood glucose was achieved with NIR diffusion reflectance spectrum method. The thumb fingertip NIR diffusion reflectance spectra of six different age healthy volunteers were collected using Nexus-870 and its NIR fiber port smart accessory. The test was implemented with changing the blood glucose concentration for the limosis and satiation of every volunteer. The calibration model was set up using PLS method with the smoothing, baseline correction and first derivatives pretreatment spectrum in the 7500-8500 cm(-1) region for single volunteer, the same age combination and that of different age. When the spectrum was obtained, the actual blood glucose value of every spectrun sample was demarcated using ultraviolet spectrophotometer. The correlation between the calibration value and true value for single volunteer is better than that for the combination of volunteers, the correlative coefficients are all over 0.90471, RMSECs are all less than 0.171.

Assessment of simulated lesions on primary teeth with near-infrared imaging

NASA Astrophysics Data System (ADS)

Tam, Wilson; Lee, Robert C.; Lin, Brent; Simon, Jacob C.; Fried, Daniel

2016-02-01

Previous studies have demonstrated that the structural changes on enamel due to demineralization and remineralization can be exploited through optical imaging methods such as QLF, thermal and NIR imaging. The purpose of this study is to investigate whether PS-OCT and NIR reflectance imaging can be utilized to assess lesion structure in artificial enamel lesions on the smooth surfaces of primary teeth exposed to fluoride. The smooth coronal surfaces of primary teeth (n=25) were divided into 4 windows: sound, demineralization, demineralization with remineralization and APF with demineralization. Windows were treated with either acidulated phosphate fluoride (APF) for 1 minute, a demineralization solution for 4 days, and/or an acidic remineralization solution for 12 days. The samples were imaged using PS-OCT, QLF and NIR reflectance at 1400-1700 nm wavelengths. This study demonstrated that both PS-OCT and NIR reflectance imaging were suitable for assessing lesion structure in the smooth surfaces of primary dentition.

Assessment of simulated lesions on primary teeth with near-infrared imaging.

PubMed

Tam, Wilson; Lee, Robert C; Lin, Brent; Simon, Jacob C; Fried, Daniel

2016-02-13

Previous studies have demonstrated that the structural changes on enamel due to demineralization and remineralization can be exploited through optical imaging methods such as QLF, thermal and NIR imaging. The purpose of this study is to investigate whether PS-OCT and NIR reflectance imaging can be utilized to assess lesion structure in artificial enamel lesions on the smooth surfaces of primary teeth exposed to fluoride. The smooth coronal surfaces of primary teeth (n=25) were divided into 4 windows: sound, demineralization, demineralization with remineralization and APF with demineralization. Windows were treated with either acidulated phosphate fluoride (APF) for 1 minute, a demineralization solution for 4 days, and/or an acidic remineralization solution for 12 days. The samples were imaged using PS-OCT, QLF and NIR reflectance at 1400-1700 nm wavelengths. This study demonstrated that both PS-OCT and NIR reflectance imaging were suitable for assessing lesion structure in the smooth surfaces of primary dentition.

Application of miniaturized near-infrared spectroscopy for quality control of extemporaneous orodispersible films.

PubMed

Foo, Wen Chin; Widjaja, Effendi; Khong, Yuet Mei; Gokhale, Rajeev; Chan, Sui Yung

2018-02-20

Extemporaneous oral preparations are routinely compounded in the pharmacy due to a lack of suitable formulations for special populations. Such small-scale pharmacy preparations also present an avenue for individualized pharmacotherapy. Orodispersible films (ODF) have increasingly been evaluated as a suitable dosage form for extemporaneous oral preparations. Nevertheless, as with all other extemporaneous preparations, safety and quality remain a concern. Although the United States Pharmacopeia (USP) recommends analytical testing of compounded preparations for quality assurance, pharmaceutical assays are typically not routinely performed for such non-sterile pharmacy preparations, due to the complexity and high cost of conventional assay methods such as high performance liquid chromatography (HPLC). Spectroscopic methods including Raman, infrared and near-infrared spectroscopy have been successfully applied as quality control tools in the industry. The state-of-art benchtop spectrometers used in those studies have the advantage of superior resolution and performance, but are not suitable for use in a small-scale pharmacy setting. In this study, we investigated the application of a miniaturized near infrared (NIR) spectrometer as a quality control tool for identification and quantification of drug content in extemporaneous ODFs. Miniaturized near infrared (NIR) spectroscopy is suitable for small-scale pharmacy applications in view of its small size, portability, simple user interface, rapid measurement and real-time prediction results. Nevertheless, the challenge with miniaturized NIR spectroscopy is its lower resolution compared to state-of-art benchtop equipment. We have successfully developed NIR spectroscopy calibration models for identification of ODFs containing five different drugs, and quantification of drug content in ODFs containing 2-10mg ondansetron (OND). The qualitative model for drug identification produced 100% prediction accuracy. The quantitative model to predict OND drug content in ODFs was divided into two calibrations for improved accuracy: Calibration I and II covered the 2-4mg and 4-10mg ranges respectively. Validation was performed for method accuracy, linearity and precision. In conclusion, this study demonstrates the feasibility of miniaturized NIR spectroscopy as a quality control tool for small-scale, pharmacy preparations. Due to its non-destructive nature, every dosage unit can be tested thus affording positive impact on patient safety. Copyright © 2017 Elsevier B.V. All rights reserved.

Taking NIRS to the field

USDA-ARS?s Scientific Manuscript database

Forage nutritive value (i.e., forage quality) impacts livestock health and performance, but determining the quality of forages for grazing animals is difficult. In the 1970s, development and application of bench-top near-infrared spectroscopy (NIRS) techniques to assess forage quality proved to be ...

[Nondestructive discrimination of strawberry varieties by NIR and BP-ANN].

PubMed

Niu, Xiao-ying; Shao, Li-min; Zhao, Zhi-lei; Zhang, Xiao-yu

2012-08-01

Strawberry variety is a main factor that can influence strawberry fruit quality. The use of near-infrared reflectance spectroscopy was explored discriminate among samples of strawberry of different varieties. And the significance of difference among different varieties was analyzed by comparison of the chemical composition of the different varieties samples. The performance of models established using back propagation-artificial neural networks (BP-ANN), least squares-support vector machine and discriminant analysis were evaluated on spectra range of 4545-9090 cm(-1). The optimal model was obtained by BP-ANN with a topology of 12-18-3, which correctly classified 96.68% of calibration set and 97.14% of prediction set. And the 94.95%, 97% and 98.29% classifications were given respectively for "Tianbao" (n=99), "Fengxiang" (n=100) and "Mingxing" (n=117). One-way analysis of variance was made for comparison of the mean values for soluble solids content (SSC), titratable acid (TA), pH value and SSC-TA ratio, and the statistically significant differences were found. Principal component analysis was performed on the four chemical compositions, and obvious clustering tendencies for different varieties were found. These results showed that NIR combined with BP-ANN can discriminate strawberry of different varieties effectively, and the difference in chemical compositions of different varieties strawberry might be a chemical validation for NIR results.

A systematic review of near-infrared spectroscopy in flap monitoring: Current basic and clinical evidence and prospects.

PubMed

Kagaya, Yu; Miyamoto, Shimpei

2018-02-01

Near-infrared spectroscopy (NIRS) has been reported to be a reliable non-invasive modality for free flap monitoring; however, the history of its application in flap monitoring is short, and there is no definite consensus regarding its use at present. The aim of this review is to clarify the evidence related to post-operative flap monitoring using NIRS and examine its appropriateness and usability. The PubMed and Web of Science databases were searched using the strings "flap monitoring AND near-infrared spectroscopy" and "flap monitoring AND tissue oxygen saturation," with a study period from inception to December 31, 2016. Two authors independently extracted articles and assessed the quality of the studies. Articles related to NIRS for flap perfusion monitoring were classified and selected regardless of study type. A total of 15 clinical studies and 8 animal studies were identified and reviewed. The evidence and information on various aspects of NIRS flap monitoring were summarized. The overall flap success rate was 99.5%, and the flap salvage rate was 91.1%, when measuring StO 2 at intervals of every 2 h or sooner. Single StO 2 monitoring was able to detect vascular compromise with 99.1% sensitivity and 99.9% specificity, and earlier than other monitoring methods, but additional Hb concentration monitoring was useful for avoiding false negatives and differentiating arterial and venous occlusion. NIRS can be used for flap monitoring and displays high accuracy in various situations; however, further studies are needed to take full advantage of the potential of NIRS. Copyright © 2017 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Near-Infrared Spectroscopy: More Accurate Than Heart Rate for Monitoring Intensity in Running in Hilly Terrain.

PubMed

Born, Dennis-Peter; Stöggl, Thomas; Swarén, Mikael; Björklund, Glenn

2017-04-01

To investigate the cardiorespiratory and metabolic response of trail running and evaluate whether heart rate (HR) adequately reflects the exercise intensity or if the tissue-saturation index (TSI) could provide a more accurate measure during running in hilly terrain. Seventeen competitive runners (4 women, V̇O 2 max, 55 ± 6 mL · kg -1 · min -1 ; 13 men, V̇O 2 max, 68 ± 6 mL · kg -1 · min -1 ) performed a time trial on an off-road trail course. The course was made up of 2 laps covering a total distance of 7 km and included 6 steep uphill and downhill sections with an elevation gain of 486 m. All runners were equipped with a portable breath-by-breath gas analyzer, HR belt, global positioning system receiver, and near-infrared spectroscopy (NIRS) device to measure the TSI. During the trail run, the exercise intensity in the uphill and downhill sections was 94% ± 2% and 91% ± 3% of maximal heart rate, respectively, and 84% ± 8% and 68% ± 7% of V̇O 2 max, respectively. The oxygen uptake (V̇O 2 ) increased in the uphill sections and decreased in the downhill sections (P < .01). Although HR was unaffected by the altering slope conditions, the TSI was inversely correlated to the changes in V̇O 2 (r = -.70, P < .05). HR was unaffected by the continuously changing exercise intensity; however, TSI reflected the alternations in V̇O 2 . Recently used exclusively for scientific purposes, this NIRS-based variable may offer a more accurate alternative than HR to monitor running intensity in the future, especially for training and competition in hilly terrain.

Rapid determination of sugar level in snack products using infrared spectroscopy.

PubMed

Wang, Ting; Rodriguez-Saona, Luis E

2012-08-01

Real-time spectroscopic methods can provide a valuable window into food manufacturing to permit optimization of production rate, quality and safety. There is a need for cutting edge sensor technology directed at improving efficiency, throughput and reliability of critical processes. The aim of the research was to evaluate the feasibility of infrared systems combined with chemometric analysis to develop rapid methods for determination of sugars in cereal products. Samples were ground and spectra were collected using a mid-infrared (MIR) spectrometer equipped with a triple-bounce ZnSe MIRacle attenuated total reflectance accessory or Fourier transform near infrared (NIR) system equipped with a diffuse reflection-integrating sphere. Sugar contents were determined using a reference HPLC method. Partial least squares regression (PLSR) was used to create cross-validated calibration models. The predictability of the models was evaluated on an independent set of samples and compared with reference techniques. MIR and NIR spectra showed characteristic absorption bands for sugars, and generated excellent PLSR models (sucrose: SEP < 1.7% and r > 0.96). Multivariate models accurately and precisely predicted sugar level in snacks allowing for rapid analysis. This simple technique allows for reliable prediction of quality parameters, and automation enabling food manufacturers for early corrective actions that will ultimately save time and money while establishing a uniform quality. The U.S. snack food industry generates billions of dollars in revenue each year and vibrational spectroscopic methods combined with pattern recognition analysis could permit optimization of production rate, quality, and safety of many food products. This research showed that infrared spectroscopy is a powerful technique for near real-time (approximately 1 min) assessment of sugar content in various cereal products. © 2012 Institute of Food Technologists®

Application of visible/near-infrared reflectance spectroscopy for predicting internal and external quality in pepper.

PubMed

Toledo-Martín, Eva María; García-García, María Carmen; Font, Rafael; Moreno-Rojas, José Manuel; Gómez, Pedro; Salinas-Navarro, María; Del Río-Celestino, Mercedes

2016-07-01

The characterization of internal (°Brix, pH, malic acid, total phenolic compounds, ascorbic acid and total carotenoid content) and external (color, firmness and pericarp wall thickness) pepper quality is necessary to better understand its possible applications and increase consumer awareness of its benefits. The main aim of this work was to examine the feasibility of using visible/near-infrared reflectance spectroscopy (VIS-NIRS) to predict quality parameters in different pepper types. Commercially available spectrophotometers were evaluated for this purpose: a Polychromix Phazir spectrometer for intact raw pepper, and a scanning monochromator for freeze-dried pepper. The RPD values (ratio of the standard deviation of the reference data to the standard error of prediction) obtained from the external validation exceeded a value of 3 for chlorophyll a and total carotenoid content; values ranging between 2.5 < RPD < 3 for total phenolic compounds; between 1.5 < RPD <2.5 for °Brix, pH, color parameters a* and h* and chlorophyll b; and RPD values below 1.5 for fruit firmness, pericarp wall thickness, color parameters C*, b* and L*, vitamin C and malic acid content. The present work has led to the development of multi-type calibrations for pepper quality parameters in intact and freeze-dried peppers. The majority of NIRS equations obtained were suitable for screening purposes in pepper breeding programs. Components such as pigments (xanthophyll, carotenes and chlorophyll), glucides, lipids, cellulose and water were used by modified partial least-squares regression for modeling the predicting equations. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Identifying and quantifying main components of physiological noise in functional near infrared spectroscopy on the prefrontal cortex.

PubMed

Kirilina, Evgeniya; Yu, Na; Jelzow, Alexander; Wabnitz, Heidrun; Jacobs, Arthur M; Tachtsidis, Ilias

2013-01-01

Functional Near-Infrared Spectroscopy (fNIRS) is a promising method to study functional organization of the prefrontal cortex. However, in order to realize the high potential of fNIRS, effective discrimination between physiological noise originating from forehead skin haemodynamic and cerebral signals is required. Main sources of physiological noise are global and local blood flow regulation processes on multiple time scales. The goal of the present study was to identify the main physiological noise contributions in fNIRS forehead signals and to develop a method for physiological de-noising of fNIRS data. To achieve this goal we combined concurrent time-domain fNIRS and peripheral physiology recordings with wavelet coherence analysis (WCA). Depth selectivity was achieved by analyzing moments of photon time-of-flight distributions provided by time-domain fNIRS. Simultaneously, mean arterial blood pressure (MAP), heart rate (HR), and skin blood flow (SBF) on the forehead were recorded. WCA was employed to quantify the impact of physiological processes on fNIRS signals separately for different time scales. We identified three main processes contributing to physiological noise in fNIRS signals on the forehead. The first process with the period of about 3 s is induced by respiration. The second process is highly correlated with time lagged MAP and HR fluctuations with a period of about 10 s often referred as Mayer waves. The third process is local regulation of the facial SBF time locked to the task-evoked fNIRS signals. All processes affect oxygenated haemoglobin concentration more strongly than that of deoxygenated haemoglobin. Based on these results we developed a set of physiological regressors, which were used for physiological de-noising of fNIRS signals. Our results demonstrate that proposed de-noising method can significantly improve the sensitivity of fNIRS to cerebral signals.

The physiological origin of task-evoked systemic artefacts in functional near infrared spectroscopy.

PubMed

Kirilina, Evgeniya; Jelzow, Alexander; Heine, Angela; Niessing, Michael; Wabnitz, Heidrun; Brühl, Rüdiger; Ittermann, Bernd; Jacobs, Arthur M; Tachtsidis, Ilias

2012-05-15

A major methodological challenge of functional near-infrared spectroscopy (fNIRS) is its high sensitivity to haemodynamic fluctuations in the scalp. Superficial fluctuations contribute on the one hand to the physiological noise of fNIRS, impairing the signal-to-noise ratio, and may on the other hand be erroneously attributed to cerebral changes, leading to false positives in fNIRS experiments. Here we explore the localisation, time course and physiological origin of task-evoked superficial signals in fNIRS and present a method to separate them from cortical signals. We used complementary fNIRS, fMRI, MR-angiography and peripheral physiological measurements (blood pressure, heart rate, skin conductance and skin blood flow) to study activation in the frontal lobe during a continuous performance task. The General Linear Model (GLM) was applied to analyse the fNIRS data, which included an additional predictor to account for systemic changes in the skin. We found that skin blood volume strongly depends on the cognitive state and that sources of task-evoked systemic signals in fNIRS are co-localized with veins draining the scalp. Task-evoked superficial artefacts were mainly observed in concentration changes of oxygenated haemoglobin and could be effectively separated from cerebral signals by GLM analysis. Based on temporal correlation of fNIRS and fMRI signals with peripheral physiological measurements we conclude that the physiological origin of the systemic artefact is a task-evoked sympathetic arterial vasoconstriction followed by a decrease in venous volume. Since changes in sympathetic outflow accompany almost any cognitive and emotional process, we expect scalp vessel artefacts to be present in a wide range of fNIRS settings used in neurocognitive research. Therefore a careful separation of fNIRS signals originating from activated brain and from scalp is a necessary precondition for unbiased fNIRS brain activation maps. Copyright © 2012 Elsevier Inc. All rights reserved.

Exploring the use of optical flow for the study of functional NIRS signals

NASA Astrophysics Data System (ADS)

Fernandez Rojas, Raul; Huang, Xu; Ou, Keng-Liang; Hernandez-Juarez, Jesus

2017-03-01

Near infrared spectroscopy (NIRS) is an optical imaging technique that allows real-time measurements of Oxy and Deoxy-hemoglobin concentrations in human body tissue. In functional NIRS (fNIRS), this technique is used to study cortical activation in response to changes in neural activity. However, analysis of activation regions using NIRS is a challenging task in the field of medical image analysis and despite existing solutions, no homogeneous analysis method has yet been determined. For that reason, the aim of our present study is to report the use of an optical flow method for the analysis of cortical activation using near-infrared spectroscopy signals. We used real fNIRS data recorded from a noxious stimulation experiment as base of our implementation. To compute the optical flow algorithm, we first arrange NIRS signals (Oxy-hemoglobin) following our 24 channels (12 channels per hemisphere) head-probe configuration to create image-like samples. We then used two consecutive fNIRS samples per hemisphere as input frames for the optical flow algorithm, making one computation per hemisphere. The output from these two computations is the velocity field representing cortical activation from each hemisphere. The experimental results showed that the radial structure of flow vectors exhibited the origin of cortical activity, the development of stimulation as expansion or contraction of such flow vectors, and the flow of activation patterns may suggest prediction in cortical activity. The present study demonstrates that optical flow provides a power tool for the analysis of NIRS signals. Finally, we suggested a novel idea to identify pain status in nonverbal patients by using optical flow motion vectors; however, this idea will be study further in our future research.

Cerebral blood volume in humans by NIRS and PET

NASA Astrophysics Data System (ADS)

Pott, Frank; Knudsen, Gitte M.; Rostrup, Egill; Ide, Kojiro; Secher, Niels H.; Paulson, Olaf B.

1997-12-01

Near infrared spectroscopy (NIRS) determined changes in the cerebral blood volume (CBV) were compared to those obtained by positron emission tomography (PET) in five healthy volunteers (2 females). Two NIRS optodes were placed on the left forehead and NIRS-CBV was derived from the sum of oxyhemoglobin and deoxyhemoglobin. CBV changes were induced by hyperventilation and inhalation of 6% CO2. After 2 min inhalation of labeled carbon monoxide, data were sampled during 8 min for both PET- and NIRS-CBV as well as for the arterial carbon dioxide tension (PaCO2). The region of interest for PET-CBV was `banana-shaped' with boundaries corresponding to the position of the NIRS optodes on the transmission scan and to a depth of approximately 2 cm. During hyperventilation, PaCO2 decreased from 5.2 (4.6 - 5.8) to 4.6 (4.2 - 4.9) kPa and equally PET-CBV (from 3.9 (2.5 - 5.2) to 3.6 (3.0 - 4.8) ml (DOT) 100 g-1) and NIRS-CBV were reduced (by -0.14 [-0.38 - 0.50] ml (DOT) 100 g-1). During hypercapnia PaCO2 increased to 6.0 (5.9 - 7.0) kPa accompanied by parallel changes in PET- (to 4.5 (3.9 - 4.9) ml (DOT) 100 g-1) and NIRS-CBV (by 0.04 [-0.02 - 0.30] ml (DOT) 100 g-1) and the two variables were correlated (r equals 0.78, p < 0.05). In conclusion, with a moderate change in the arterial carbon dioxide tension, the cerebral blood volumes determined by near infrared spectroscopy and by positron emission tomography change in parallel but the change in NIRS-CBV is small compared to that obtained by PET.

Cerebral blood volume in humans by NIRS and PET

NASA Astrophysics Data System (ADS)

Pott, Frank; Knudsen, Gitte M.; Rostrup, Egill; Ide, Kojiro; Secher, Niels H.; Paulson, Olaf B.

1998-01-01

Near infrared spectroscopy (NIRS) determined changes in the cerebral blood volume (CBV) were compared to those obtained by positron emission tomography (PET) in five healthy volunteers (2 females). Two NIRS optodes were placed on the left forehead and NIRS-CBV was derived from the sum of oxyhemoglobin and deoxyhemoglobin. CBV changes were induced by hyperventilation and inhalation of 6% CO2. After 2 min inhalation of labeled carbon monoxide, data were sampled during 8 min for both PET- and NIRS-CBV as well as for the arterial carbon dioxide tension (PaCO2). The region of interest for PET-CBV was `banana-shaped' with boundaries corresponding to the position of the NIRS optodes on the transmission scan and to a depth of approximately 2 cm. During hyperventilation, PaCO2 decreased from 5.2 (4.6 - 5.8) to 4.6 (4.2 - 4.9) kPa and equally PET-CBV (from 3.9 (2.5 - 5.2) to 3.6 (3.0 - 4.8) ml (DOT) 100 g-1) and NIRS-CBV were reduced (by -0.14 [-0.38 - 0.50] ml (DOT) 100 g-1). During hypercapnia PaCO2 increased to 6.0 (5.9 - 7.0) kPa accompanied by parallel changes in PET- (to 4.5 (3.9 - 4.9) ml (DOT) 100 g-1) and NIRS-CBV (by 0.04 [-0.02 - 0.30] ml (DOT) 100 g-1) and the two variables were correlated (r equals 0.78, p < 0.05). In conclusion, with a moderate change in the arterial carbon dioxide tension, the cerebral blood volumes determined by near infrared spectroscopy and by positron emission tomography change in parallel but the change in NIRS-CBV is small compared to that obtained by PET.

Label-free NIR reflectance imaging as a complimentary tool for two-photon fluorescence microscopy: multimodal investigation of stroke (Conference Presentation)

NASA Astrophysics Data System (ADS)

Allegra Mascaro, Anna Letizia; Costantini, Irene; Margoni, Emilia; Iannello, Giulio; Bria, Alessandro; Sacconi, Leonardo; Pavone, Francesco S.

2016-03-01

Two-photon imaging combined with targeted fluorescent indicators is extensively used for visualizing critical features of brain functionality and structural plasticity. Back-scattered photons from the NIR laser provide complimentary information without introducing any exogenous labelling. Here, we describe a versatile approach that, by collecting the reflected NIR light, provides structural details on the myelinated axons and blood vessels in the brain, both in fixed samples and in live animals. Indeed, by combining NIR reflectance and two-photon imaging of a slice of hippocampus from Thy1-GFPm mice, we show the presence of randomly oriented axons intermingled with sparsely fluorescent neuronal processes. The back-scattered photons guide the contextualization of the fluorescence structure within brain atlas thanks to the recognition of characteristic hippocampal structures. Label-free detection of axonal elongations over the layer 2/3 of mouse cortex under a cranial window was also possible in live brain. Finally, blood flow could be measured in vivo, thus validating label free NIR reflectance as a tool for monitoring hemodynamic fluctuations. The prospective versatility of this label-free technique complimentary to two-photon fluorescence microscopy is demonstrated in a mouse model of photothrombotic stroke in which the axonal degeneration and blood flow remodeling can be investigated simultaneously.

On-line monitoring the extract process of Fu-fang Shuanghua oral solution using near infrared spectroscopy and different PLS algorithms

NASA Astrophysics Data System (ADS)

Kang, Qian; Ru, Qingguo; Liu, Yan; Xu, Lingyan; Liu, Jia; Wang, Yifei; Zhang, Yewen; Li, Hui; Zhang, Qing; Wu, Qing

2016-01-01

An on-line near infrared (NIR) spectroscopy monitoring method with an appropriate multivariate calibration method was developed for the extraction process of Fu-fang Shuanghua oral solution (FSOS). On-line NIR spectra were collected through two fiber optic probes, which were designed to transmit NIR radiation by a 2 mm flange. Partial least squares (PLS), interval PLS (iPLS) and synergy interval PLS (siPLS) algorithms were used comparatively for building the calibration regression models. During the extraction process, the feasibility of NIR spectroscopy was employed to determine the concentrations of chlorogenic acid (CA) content, total phenolic acids contents (TPC), total flavonoids contents (TFC) and soluble solid contents (SSC). High performance liquid chromatography (HPLC), ultraviolet spectrophotometric method (UV) and loss on drying methods were employed as reference methods. Experiment results showed that the performance of siPLS model is the best compared with PLS and iPLS. The calibration models for AC, TPC, TFC and SSC had high values of determination coefficients of (R2) (0.9948, 0.9992, 0.9950 and 0.9832) and low root mean square error of cross validation (RMSECV) (0.0113, 0.0341, 0.1787 and 1.2158), which indicate a good correlation between reference values and NIR predicted values. The overall results show that the on line detection method could be feasible in real application and would be of great value for monitoring the mixed decoction process of FSOS and other Chinese patent medicines.

Cortical activation patterns to spatially presented pure tone stimuli with different intensities measured by functional near-infrared spectroscopy.

PubMed

Bauernfeind, Günther; Wriessnegger, Selina C; Haumann, Sabine; Lenarz, Thomas

2018-03-08

Functional near-infrared spectroscopy (fNIRS) is an emerging technique for the assessment of functional activity of the cerebral cortex. Recently fNIRS was also envisaged as a novel neuroimaging approach for measuring the auditory cortex activity in the field of in auditory diagnostics. This study aimed to investigate differences in brain activity related to spatially presented sounds with different intensities in 10 subjects by means of functional near-infrared spectroscopy (fNIRS). We found pronounced cortical activation patterns in the temporal and frontal regions of both hemispheres. In contrast to these activation patterns, we found deactivation patterns in central and parietal regions of both hemispheres. Furthermore our results showed an influence of spatial presentation and intensity of the presented sounds on brain activity in related regions of interest. These findings are in line with previous fMRI studies which also reported systematic changes of activation in temporal and frontal areas with increasing sound intensity. Although clear evidence for contralaterality effects and hemispheric asymmetries were absent in the group data, these effects were partially visible on the single subject level. Concluding, fNIRS is sensitive enough to capture differences in brain responses during the spatial presentation of sounds with different intensities in several cortical regions. Our results may serve as a valuable contribution for further basic research and the future use of fNIRS in the area of central auditory diagnostics. © 2018 Wiley Periodicals, Inc.

Assessment of beer quality based on foamability and chemical composition using computer vision algorithms, near infrared spectroscopy and machine learning algorithms.

PubMed

Gonzalez Viejo, Claudia; Fuentes, Sigfredo; Torrico, Damir; Howell, Kate; Dunshea, Frank R

2018-01-01

Beer quality is mainly defined by its colour, foamability and foam stability, which are influenced by the chemical composition of the product such as proteins, carbohydrates, pH and alcohol. Traditional methods to assess specific chemical compounds are usually time-consuming and costly. This study used rapid methods to evaluate 15 foam and colour-related parameters using a robotic pourer (RoboBEER) and chemical fingerprinting using near infrared spectroscopy (NIR) from six replicates of 21 beers from three types of fermentation. Results from NIR were used to create partial least squares regression (PLS) and artificial neural networks (ANN) models to predict four chemometrics such as pH, alcohol, Brix and maximum volume of foam. The ANN method was able to create more accurate models (R 2  = 0.95) compared to PLS. Principal components analysis using RoboBEER parameters and NIR overtones related to protein explained 67% of total data variability. Additionally, a sub-space discriminant model using the absorbance values from NIR wavelengths resulted in the successful classification of 85% of beers according to fermentation type. The method proposed showed to be a rapid system based on NIR spectroscopy and RoboBEER outputs of foamability that can be used to infer the quality, production method and chemical parameters of beer with minimal laboratory equipment. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

A NIR spectroscopy-based efficient approach to detect fraudulent additions within mixtures of dried porcini mushrooms.

PubMed

Casale, Monica; Bagnasco, Lucia; Zotti, Mirca; Di Piazza, Simone; Sitta, Nicola; Oliveri, Paolo

2016-11-01

Boletus edulis and allied species (BEAS), known as "porcini mushrooms", represent almost the totality of wild mushrooms placed on the Italian market, both fresh and dehydrated. Furthermore, considerable amounts of these dried fungi are imported from China. The presence of Tylopilus spp. and other extraneous species (i.e., species edible but not belonging to BEAS) within dried porcini mushrooms - mainly from those imported from China and sold in Italy - may represent an evaluable problem from a commercial point of view. The purpose of the present study is to evaluate near-infrared spectroscopy (NIRS) as a rapid and effective alternative to classical methods for identifying extraneous species within dried porcini batches and detecting related commercial frauds. To this goal, 80 dried fungi including BEAS, Tylopilus spp., and Boletus violaceofuscus were analysed by NIRS. For each sample, 3 different parts of the pileus (pileipellis, flesh and hymenium) were analysed and a low-level strategy for data fusion, consisting of combining the signals obtained by the different parts before data processing, was applied. Then, NIR spectra were used to develop reliable and efficient class-models using a novel method, partial least squares density modelling (PLS-DM), and the two most commonly used class-modelling techniques, UNEQ and SIMCA. The results showed that NIR spectroscopy coupled with chemometric class-modelling technique can be suggested as an effective analytical strategy to check the authenticity of dried BEAS mushrooms. Copyright © 2016 Elsevier B.V. All rights reserved.

[Studies on the brand traceability of milk powder based on NIR spectroscopy technology].

PubMed

Guan, Xiao; Gu, Fang-Qing; Liu, Jing; Yang, Yong-Jian

2013-10-01

Brand traceability of several different kinds of milk powder was studied by combining near infrared spectroscopy diffuse reflectance mode with soft independent modeling of class analogy (SIMCA) in the present paper. The near infrared spectrum of 138 samples, including 54 Guangming milk powder samples, 43 Netherlands samples, and 33 Nestle samples and 8 Yili samples, were collected. After pretreatment of full spectrum data variables in training set, principal component analysis was performed, and the contribution rate of the cumulative variance of the first three principal components was about 99.07%. Milk powder principal component regression model based on SIMCA was established, and used to classify the milk powder samples in prediction sets. The results showed that the recognition rate of Guangming milk powder, Netherlands milk powder and Nestle milk powder was 78%, 75% and 100%, the rejection rate was 100%, 87%, and 88%, respectively. Therefore, the near infrared spectroscopy combined with SIMCA model can classify milk powder with high accuracy, and is a promising identification method of milk powder variety.

Application of infrared reflection and Raman spectroscopy for quantitative determination of fat in potato chips

NASA Astrophysics Data System (ADS)

Mazurek, Sylwester; Szostak, Roman; Kita, Agnieszka

2016-12-01

Potato chips are important products in the snack industry. The most significant parameter monitored during their quality control process is fat content. The Soxhlet method, which is applied for this purpose, is time consuming and expensive. We demonstrate that both infrared and Raman spectroscopy can effectively replace the extraction method. Raman, mid-infrared (MIR) and near-infrared (NIR) spectra of the homogenised laboratory-prepared chips were recorded. On the basis of obtained spectra, partial least squares (PLS) calibration models were constructed. They were characterised by the values of relative standard errors of prediction (RSEP) in the 1.0-1.9% range for both calibration and validation data sets. Using the developed models, six commercial products were successfully quantified with recovery in the 98.5-102.3% range against the AOAC extraction method. The proposed method for fat quantification in potato chips based on Raman spectroscopy can be easily adopted for on-line product analysis.

Cobalt Oxide Nanoclusters on Rutile Titania as Bifunctional Units for Water Oxidation Catalysis and Visible Light Absorption: Understanding the Structure-Activity Relationship.

PubMed

Maeda, Kazuhiko; Ishimaki, Koki; Okazaki, Megumi; Kanazawa, Tomoki; Lu, Daling; Nozawa, Shunsuke; Kato, Hideki; Kakihana, Masato

2017-02-22

The structure of cobalt oxide (CoO x ) nanoparticles dispersed on rutile TiO 2 (R-TiO 2 ) was characterized by X-ray diffraction, UV-vis-NIR diffuse reflectance spectroscopy, high-resolution transmission electron microscopy, X-ray absorption fine-structure spectroscopy, and X-ray photoelectron spectroscopy. The CoO x nanoparticles were loaded onto R-TiO 2 by an impregnation method from an aqueous solution containing Co(NO 3 ) 2 ·6H 2 O followed by heating in air. Modification of the R-TiO 2 with 2.0 wt % Co followed by heating at 423 K for 1 h resulted in the highest photocatalytic activity with good reproducibility. Structural analyses revealed that the activity of this photocatalyst depended strongly on the generation of Co 3 O 4 nanoclusters with an optimal distribution. These nanoclusters are thought to interact with the R-TiO 2 surface, resulting in visible light absorption and active sites for water oxidation.

Characterising protein, salt and water interactions with combined vibrational spectroscopic techniques.

PubMed

Perisic, Nebojsa; Afseth, Nils Kristian; Ofstad, Ragni; Hassani, Sahar; Kohler, Achim

2013-05-01

In this paper a combination of NIR spectroscopy and FTIR and Raman microspectroscopy was used to elucidate the effects of different salts (NaCl, KCl and MgSO(4)) on structural proteins and their hydration in muscle tissue. Multivariate multi-block technique Consensus Principal Component Analysis enabled integration of different vibrational spectroscopic techniques: macroscopic information obtained by NIR spectroscopy is directly related to microscopic information obtained by FTIR and Raman microspectroscopy. Changes in protein secondary structure observed at different concentrations of salts were linked to changes in protein hydration affinity. The evidence for this was given by connecting the underlying FTIR bands of the amide I region (1700-1600 cm(-1)) and the water region (3500-3000 cm(-1)) with water vibrations obtained by NIR spectroscopy. In addition, Raman microspectroscopy demonstrated that different cations affected structures of aromatic amino acid residues differently, which indicates that cation-π interactions play an important role in determination of the final structure of protein molecules. Copyright © 2012 Elsevier Ltd. All rights reserved.

Rapid characterization of transgenic and non-transgenic soybean oils by chemometric methods using NIR spectroscopy

NASA Astrophysics Data System (ADS)

Luna, Aderval S.; da Silva, Arnaldo P.; Pinho, Jéssica S. A.; Ferré, Joan; Boqué, Ricard

Near infrared (NIR) spectroscopy and multivariate classification were applied to discriminate soybean oil samples into non-transgenic and transgenic. Principal Component Analysis (PCA) was applied to extract relevant features from the spectral data and to remove the anomalous samples. The best results were obtained when with Support Vectors Machine-Discriminant Analysis (SVM-DA) and Partial Least Squares-Discriminant Analysis (PLS-DA) after mean centering plus multiplicative scatter correction. For SVM-DA the percentage of successful classification was 100% for the training group and 100% and 90% in validation group for non transgenic and transgenic soybean oil samples respectively. For PLS-DA the percentage of successful classification was 95% and 100% in training group for non transgenic and transgenic soybean oil samples respectively and 100% and 80% in validation group for non transgenic and transgenic respectively. The results demonstrate that NIR spectroscopy can provide a rapid, nondestructive and reliable method to distinguish non-transgenic and transgenic soybean oils.

Determination of polyphenolic compounds of red wines by UV-VIS-NIR spectroscopy and chemometrics tools.

PubMed

Martelo-Vidal, M J; Vázquez, M

2014-09-01

Spectral analysis is a quick and non-destructive method to analyse wine. In this work, trans-resveratrol, oenin, malvin, catechin, epicatechin, quercetin and syringic acid were determined in commercial red wines from DO Rías Baixas and DO Ribeira Sacra (Spain) by UV-VIS-NIR spectroscopy. Calibration models were developed using principal component regression (PCR) or partial least squares (PLS) regression. HPLC was used as reference method. The results showed that reliable PLS models were obtained to quantify all polyphenols for Rías Baixas wines. For Ribeira Sacra, feasible models were obtained to determine quercetin, epicatechin, oenin and syringic acid. PCR calibration models showed worst reliable of prediction than PLS models. For red wines from mencía grapes, feasible models were obtained for catechin and oenin, regardless the geographical origin. The results obtained demonstrate that UV-VIS-NIR spectroscopy can be used to determine individual polyphenolic compounds in red wines. Copyright © 2014 Elsevier Ltd. All rights reserved.

Rapid monitoring of the fermentation process for Korean traditional rice wine 'Makgeolli' using FT-NIR spectroscopy

NASA Astrophysics Data System (ADS)

Kim, Dae-Yong; Cho, Byoung-Kwan

2015-11-01

The quality parameters of the Korean traditional rice wine "Makgeolli" were monitored using Fourier transform near-infrared (FT-NIR) spectroscopy with multivariate statistical analysis (MSA) during fermentation. Alcohol, reducing sugar, and titratable acid were the parameters assessed to determine the quality index of fermentation substrates and products. The acquired spectra were analyzed with partial least squares regression (PLSR). The best prediction model for alcohol was obtained with maximum normalization, showing a coefficient of determination (Rp2) of 0.973 and a standard error of prediction (SEP) of 0.760%. In addition, the best prediction model for reducing sugar was obtained with no data preprocessing, with a Rp2 value of 0.945 and a SEP of 1.233%. The prediction of titratable acidity was best with mean normalization, showing a Rp2 value of 0.882 and a SEP of 0.045%. These results demonstrate that FT-NIR spectroscopy can be used for rapid measurements of quality parameters during Makgeolli fermentation.

Estimation of Anthocyanin Content of Berries by NIR Method

NASA Astrophysics Data System (ADS)

Zsivanovits, G.; Ludneva, D.; Iliev, A.

2010-01-01

Anthocyanin contents of fruits were estimated by VIS spectrophotometer and compared with spectra measured by NIR spectrophotometer (600-1100 nm step 10 nm). The aim was to find a relationship between NIR method and traditional spectrophotometric method. The testing protocol, using NIR, is easier, faster and non-destructive. NIR spectra were prepared in pairs, reflectance and transmittance. A modular spectrocomputer, realized on the basis of a monochromator and peripherals Bentham Instruments Ltd (GB) and a photometric camera created at Canning Research Institute, were used. An important feature of this camera is the possibility offered for a simultaneous measurement of both transmittance and reflectance with geometry patterns T0/180 and R0/45. The collected spectra were analyzed by CAMO Unscrambler 9.1 software, with PCA, PLS, PCR methods. Based on the analyzed spectra quality and quantity sensitive calibrations were prepared. The results showed that the NIR method allows measuring of the total anthocyanin content in fresh berry fruits or processed products without destroying them.

Estimation of Anthocyanin Content of Berries by NIR Method

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zsivanovits, G.; Ludneva, D.; Iliev, A.

2010-01-21

Anthocyanin contents of fruits were estimated by VIS spectrophotometer and compared with spectra measured by NIR spectrophotometer (600-1100 nm step 10 nm). The aim was to find a relationship between NIR method and traditional spectrophotometric method. The testing protocol, using NIR, is easier, faster and non-destructive. NIR spectra were prepared in pairs, reflectance and transmittance. A modular spectrocomputer, realized on the basis of a monochromator and peripherals Bentham Instruments Ltd (GB) and a photometric camera created at Canning Research Institute, were used. An important feature of this camera is the possibility offered for a simultaneous measurement of both transmittance andmore » reflectance with geometry patterns T0/180 and R0/45. The collected spectra were analyzed by CAMO Unscrambler 9.1 software, with PCA, PLS, PCR methods. Based on the analyzed spectra quality and quantity sensitive calibrations were prepared. The results showed that the NIR method allows measuring of the total anthocyanin content in fresh berry fruits or processed products without destroying them.« less

Predicting Key Agronomic Soil Properties with UV-Vis Fluorescence Measurements Combined with Vis-NIR-SWIR Reflectance Spectroscopy: A Farm-Scale Study in a Mediterranean Viticultural Agroecosystem.

PubMed

Vaudour, Emmanuelle; Cerovic, Zoran G; Ebengo, Dav M; Latouche, Gwendal

2018-04-10

For adequate crop and soil management, rapid and accurate techniques for monitoring soil properties are particularly important when a farmer starts up his activities and needs a diagnosis of his cultivated fields. This study aimed to evaluate the potential of fluorescence measured directly on 146 whole soil solid samples, for predicting key soil properties at the scale of a 6 ha Mediterranean wine estate with contrasting soils. UV-Vis fluorescence measurements were carried out in conjunction with reflectance measurements in the Vis-NIR-SWIR range. Combining PLSR predictions from Vis-NIR-SWIR reflectance spectra and from a set of fluorescence signals enabled us to improve the power of prediction of a number of key agronomic soil properties including SOC, N tot , CaCO₃, iron, fine particle-sizes (clay, fine silt, fine sand), CEC, pH and exchangeable Ca 2+ with cross-validation RPD ≥ 2 and R² ≥ 0.75, while exchangeable K⁺, Na⁺, Mg 2+ , coarse silt and coarse sand contents were fairly predicted (1.42 ≤ RPD < 2 and 0.54 ≤ R² < 0.75). Predictions of SOC, N tot , CaCO₃, iron contents, and pH were still good (RPD ≥ 1.8, R² ≥ 0.68) when using a single fluorescence signal or index such as SFR_R or FERARI, highlighting the unexpected importance of red excitations and indices derived from plant studies. The predictive ability of single fluorescence indices or original signals was very significant for topsoil: this is very important for a farmer who wishes to update information on soil nutrient for the purpose of fertility diagnosis and particularly nitrogen fertilization. These results open encouraging perspectives for using miniaturized fluorescence devices enabling red excitation coupled with red or far-red fluorescence emissions directly in the field.

Predicting Key Agronomic Soil Properties with UV-Vis Fluorescence Measurements Combined with Vis-NIR-SWIR Reflectance Spectroscopy: A Farm-Scale Study in a Mediterranean Viticultural Agroecosystem

PubMed Central

Vaudour, Emmanuelle; Cerovic, Zoran G.; Ebengo, Dav M.; Latouche, Gwendal

2018-01-01

For adequate crop and soil management, rapid and accurate techniques for monitoring soil properties are particularly important when a farmer starts up his activities and needs a diagnosis of his cultivated fields. This study aimed to evaluate the potential of fluorescence measured directly on 146 whole soil solid samples, for predicting key soil properties at the scale of a 6 ha Mediterranean wine estate with contrasting soils. UV-Vis fluorescence measurements were carried out in conjunction with reflectance measurements in the Vis-NIR-SWIR range. Combining PLSR predictions from Vis-NIR-SWIR reflectance spectra and from a set of fluorescence signals enabled us to improve the power of prediction of a number of key agronomic soil properties including SOC, Ntot, CaCO3, iron, fine particle-sizes (clay, fine silt, fine sand), CEC, pH and exchangeable Ca2+ with cross-validation RPD ≥ 2 and R² ≥ 0.75, while exchangeable K+, Na+, Mg2+, coarse silt and coarse sand contents were fairly predicted (1.42 ≤ RPD < 2 and 0.54 ≤ R² < 0.75). Predictions of SOC, Ntot, CaCO3, iron contents, and pH were still good (RPD ≥ 1.8, R² ≥ 0.68) when using a single fluorescence signal or index such as SFR_R or FERARI, highlighting the unexpected importance of red excitations and indices derived from plant studies. The predictive ability of single fluorescence indices or original signals was very significant for topsoil: this is very important for a farmer who wishes to update information on soil nutrient for the purpose of fertility diagnosis and particularly nitrogen fertilization. These results open encouraging perspectives for using miniaturized fluorescence devices enabling red excitation coupled with red or far-red fluorescence emissions directly in the field. PMID:29642640

Online Removal of Baseline Shift with a Polynomial Function for Hemodynamic Monitoring Using Near-Infrared Spectroscopy.

PubMed

Zhao, Ke; Ji, Yaoyao; Li, Yan; Li, Ting

2018-01-21

Near-infrared spectroscopy (NIRS) has become widely accepted as a valuable tool for noninvasively monitoring hemodynamics for clinical and diagnostic purposes. Baseline shift has attracted great attention in the field, but there has been little quantitative study on baseline removal. Here, we aimed to study the baseline characteristics of an in-house-built portable medical NIRS device over a long time (>3.5 h). We found that the measured baselines all formed perfect polynomial functions on phantom tests mimicking human bodies, which were identified by recent NIRS studies. More importantly, our study shows that the fourth-order polynomial function acted to distinguish performance with stable and low-computation-burden fitting calibration (R-square >0.99 for all probes) among second- to sixth-order polynomials, evaluated by the parameters R-square, sum of squares due to error, and residual. This study provides a straightforward, efficient, and quantitatively evaluated solution for online baseline removal for hemodynamic monitoring using NIRS devices.

Cross-Correlation of Motor Activity Signals from dc-Magnetoencephalography, Near-Infrared Spectroscopy, and Electromyography

PubMed Central

Sander, Tilmann H.; Leistner, Stefanie; Wabnitz, Heidrun; Mackert, Bruno-Marcel; Macdonald, Rainer; Trahms, Lutz

2010-01-01

Neuronal and vascular responses due to finger movements were synchronously measured using dc-magnetoencephalography (dcMEG) and time-resolved near-infrared spectroscopy (trNIRS). The finger movements were monitored with electromyography (EMG). Cortical responses related to the finger movement sequence were extracted by independent component analysis from both the dcMEG and the trNIRS data. The temporal relations between EMG rate, dcMEG, and trNIRS responses were assessed pairwise using the cross-correlation function (CCF), which does not require epoch averaging. A positive lag on a scale of seconds was found for the maximum of the CCF between dcMEG and trNIRS. A zero lag is observed for the CCF between dcMEG and EMG. Additionally this CCF exhibits oscillations at the frequency of individual finger movements. These findings show that the dcMEG with a bandwidth up to 8 Hz records both slow and faster neuronal responses, whereas the vascular response is confirmed to change on a scale of seconds. PMID:20145717

Effects of acetazolamide on the micro- and macro-vascular cerebral hemodynamics: a diffuse optical and transcranial doppler ultrasound study

PubMed Central

Zirak, Peyman; Delgado-Mederos, Raquel; Martí-Fàbregas, Joan; Durduran, Turgut

2010-01-01

Acetazolamide (ACZ) was used to stimulate the cerebral vasculature on ten healthy volunteers to assess the cerebral vasomotor reactivity (CVR). We have combined near infrared spectroscopy (NIRS), diffuse correlation spectroscopy (DCS) and transcranial Doppler (TCD) technologies to non-invasively assess CVR in real-time by measuring oxy- and deoxy-hemoglobin concentrations, using NIRS, local cerebral blood flow (CBF), using DCS, and blood flow velocity (CBFV) in the middle cerebral artery, using TCD. Robust and persistent increases in oxy-hemoglobin concentration, CBF and CBFV were observed. A significant agreement was found between macro-vascular (TCD) and micro-vascular (DCS) hemodynamics, between the NIRS and TCD data, and also within NIRS and DCS results. The relative cerebral metabolic rate of oxygen, rCMRO2, was also determined, and no significant change was observed. Our results showed that the combined diffuse optics-ultrasound technique is viable to follow (CVR) and rCMRO2 changes in adults, continuously, at the bed-side and in real time. PMID:21258561