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Diode Array Near Infrared Spectrometer Calibrations for Composition Analysis of Single Plant Canola (Brassica napus) Seed
摘要： A canola breeder needs an accurate, rapid, non-destructive method for analyzing seeds from a single plant to select the most promising samples for further breeding trials. Near Infrared Spectroscopy (NIRS) is widely used for quantitative analysis of oilseeds in a non-destructive manner. This research was aimed at developing NIRS calibration models for single plant canola seed using a diode array NIRS (950-1650 nm wavelength range), multivariate prediction models, and a mirrored sample cup. Eighteen different NIRS calibration models were developed using 100 samples for each constituent with different pre-processing techniques (mean center, derivatives, variates) and models (PLS, PCR). The relative performance of different calibration models for each constituent was compared using R2, SEP, and ratio performance deviation (RPD) values obtained from the validation set of 30 samples. NIRS models developed using the PLS regression algorithm for moisture content (R2 = 0.97, SEP = 0.32, RPD = 6.13) and oil content (R2 = 0.84, SEP = 0.61, RPD = 4.16) were successful. However, acceptable NIRS models were not obtained for fatty acid and glucosinolates content likely due to limited variability and low levels of the constituent and a narrow wavelength range of the DA-NIR instrument.
关键词： Moisture content,Diode array,Fatty acid composition,Mirrored cup,DA-NIRS,Oil content,Oleic acid,Stearic acid,NIRS calibration model,Palmitic acid
更新于2025-09-23 15:23:52
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Detection of Knot Defects on Coniferous Wood Surface Using Near Infrared Spectroscopy and Chemometrics
摘要： Lumber pieces usually contain defects such as knots, which strongly affect the strength and stiffness. To develop a model for rapid, accurate grading of lumbers based on knots, Douglas fir, spruce-pine-fir (SPF), Chinese hemlock, and Dragon spruce were used. The experiments explored the effects of modelling methods and spectral preprocess methods for knot detection, and investigated the feasibility of using a model built within one species to discriminate the samples from other species, using a novel variable selection method-random frog to select effective wavelengths. The results showed that least squares-support vector machines coupled with first derivative preprocessed spectra achieved best performance for both single and mixed models. Models built within Dragon spruce could be used to classify knot samples from SPF and Chinese hemlock but not Douglas fir, and vice versa. Eight effective wavelengths (1314 nm, 1358 nm, 1409 nm, 1340 nm, 1260 nm, 1586 nm, 1288 nm, and 1402 nm) were selected by RF to build effective wavelengths based models. The sensitivity, specificity, and accuracy in the validation set were 98.49%, 93.42%, and 96.30%, respectively. Good results could be obtained when using data at just eight wavelengths, as an alternative to evaluating the whole spectrum.
关键词： Coniferous wood,Knot detection,Near infrared spectroscopy (NIRS),Random frog algorithm,Least squares-support vector machines (LS-SVM)
更新于2025-09-23 15:23:52
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BEAUTIFUL FACES ENHANCE VERBAL WORKING MEMORY PERFORMANCE: AN NIRS STUDY
摘要： In addition to material rewards (such as money, food, and liquid), various social signals, including facial attractiveness, are perceived as incentives. Although material and monetary rewards are known to enhance various aspects of cognitive performance, it is not clear whether and how social signals affect cognition. The present study focused on facial attractiveness and investigated its effects on working memory. In addition, we used near-infrared spectroscopy (NIRS) to characterize the activation in the dorsolateral prefrontal cortex (DLPFC), an area known to be involved in the processing of reward-related cues in working memory. Our results show that compared to the non-reward condition, the cue for attractive faces enhanced working memory performance, but DLPFC activation did not differ between these two conditions. These results provide new evidence that facial attractiveness enhances verbal working memory performance and function via neural mechanisms different from those characterized for other types of rewarding cues.
关键词： DLPFC,attractive face,working memory,reward,NIRS
更新于2025-09-23 15:22:29
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Performance comparison between a miniaturized and a conventional near infrared reflectance (NIR) spectrometer for characterizing soil carbon and nitrogen
摘要： Miniaturized near infrared spectrometers are now available, at more affordable prices than conventional spectrometers, but their performances have been poorly studied to date. This paper aimed at comparing the performances of the JDSU MicroNIR 2200 spectrophotometer (weight < 0.1 kg) with those of a conventional bench-top instrument for predicting carbon and nitrogen contents in laboratory conditions, on a range of representative Malagasy soils. Though its noticeably narrower and less resolved spectra (1151–2186 nm at 8.15 nm step vs. 1100–2498 nm at 2 nm step), the microspectrometer yielded predictions in independent validation that were almost as accurate as those of the conventional instrument (standard errors of prediction were 4.6 vs. 3.4 gC kg?1 after bias correction, and 0.36 vs. 0.35 gN kg?1, respectively). Due to noisy features, the MicroNIR spectra needed mathematical pretreatment (e.g. standard normal variate SNV), and bias correction for C, for providing accurate predictions, while the raw absorbance spectra from the conventional instrument did not. Furthermore, building multivariate models with MicroNIR spectra required less latent variables than with their conventional counterparts, and these models were less prone to performance degradation when applied to independent validation samples. Fitting the spectra of the conventional instrument to those of the MicroNIR (1150–2182 nm at 2 or 8 nm step) showed that (moderately) less accurate MicroNIR predictions could be firstly attributed to narrower spectral range rather than to poorer resolution. Considering their performances, such microspectrometers could thus represent a cost-effective alternative to conventional spectrometers. They have now to be tested in field conditions.
关键词： Near infrared reflectance spectroscopy (NIRS),Soil organic carbon,Madagascar,Soil total nitrogen,Microspectrometer
更新于2025-09-23 15:22:29
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Rapid assessment of monovarietal Portuguese Extra Virgin Olive Oil's (EVOO's) fatty acids by Fourier-transform Near-Infrared Spectroscopy (FT-NIRS)
摘要： A rapid method for the evaluation of fatty acids (FA) of monovarietal Portuguese extra virgin olive oils (EVOO) (n = 82) from Alentejo, south-central region of Portugal, was developed based on Fourier-transform near-infrared spectroscopy (FT-NIRS). The contents of FA-components (previously determined per conventional gas chromatography) were correlated with FT-NIRS data (independent variable), by means of full cross-validation partial least squares regression (CVPLSR). CVPLSR was run using standard normal variate (SNV) data pre-processing and nonlinear iterative partial least squares (NIPALS) algorithm. Obtained correlation models were characterized with good statistics: high correlation coefficients (R > 0.85) and low root mean square errors (RMSE < 2.04). Obtained values of the residual predictive deviation (RPD) of CVPLSR-model, higher than 5.0 (C18:1, C18:2, MUFA, PUFA) confirmed the FT-NIRS as a potential method for rapid quality control of EVOO’s FA.
关键词： Extra virgin olive oils,fatty acids,CVPLSR,chemometrics,FT-NIRS
更新于2025-09-23 15:22:29
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Preliminary Assessment of the Nutritional Quality of two Types of Lentils (Lens Culinaris) by Near Infrared Reflectance Spectroscopy Technology (Nirs)
摘要： The aim of this study was to evaluate and compare the nutritive value of two varieties of lentils (Lens culinaris), namely green and red varieties. For this purpose the chemical components: crude protein, starch, ash, sugars (monosaccharides and oligosaccharides), crude fat, total fibers and dry matter of two lentils varieties (green and red) were determined by near infrared reflectance spectroscopy technology (NIRS). Results show that green lentils had higher contents in ash (minerals), crude protein and total fibers, while the red lentils had higher contents in crude fat and total carbohydrates. The metabolizable energy (MJ/kg) of the red lentils was slightly higher than green lentils. In conclusion both type of lentils (green and red) revealed good nutritional quality with slight differences.
关键词： Nutritional value,Lentil (Lens culinaris),NIRS
更新于2025-09-23 15:22:29
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Development of Near-Infrared Reflectance Spectroscopy (NIRS) Calibrations for Traits Related to Ethanol Conversion from Genetically Variable Napier Grass (Pennisetum purpureum Schum.)
摘要： Napier grass (Pennisetum purpureum Schum.) is one of the highest-yielding feedstocks for bio-based products and biofuel in semi-tropical areas of the USA and the world. Thirty genetically diverse Napier grass accessions were selected from a germplasm nursery in Tifton, GA and analyzed for fiber, ash, nitrogen (N) concentration, and biochemical conversion to ethanol. A near-infrared reflectance spectroscopy (NIRS) calibration was developed from this material to predict ethanol production, xylans, N concentration, and ash by separating leaves and stems and correlating with wet chemistry analyses. The high diversity of material from dwarf material with high leaf and stem digestibility to taller and more productive Napier grass cultivars resulted in high correlations with predicted results for in vitro dry matter digestibility (2 = 0.93), neutral detergent fiber (r2 = 0.83), acid detergent fiber (r2 = 0.95), ethanol (r2 = 0.90), nitrogen (r2 = 0.99), and ash (r2 = 0.98). This information will allow faster evaluation of Napier grass biomass for use by industry or geneticists.
关键词： Biomass,Near-infrared reflectance spectroscopy (NIRS),Forage,Biofuels
更新于2025-09-23 15:21:21
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The Supplementary Motor Area Responsible for Word Retrieval Decline After Acute Thalamic Stroke Revealed by Coupled SPECT and Near-Infrared Spectroscopy
摘要： Damage to the thalamus may affect cognition and language, but the underlying mechanism remains unknown. In particular, it remains a riddle why thalamic aphasia occasionally occurs and then mostly recovers to some degree. To explore the mechanism of the affected cognition and language, we used two neuroimaging techniques—single-photon emission computed tomography (SPECT), suitable for viewing the affected brain distribution after acute thalamic stroke, and functional near-infrared spectroscopy (f-NIRS), focusing on hemodynamic responses of the supplementary motor area (SMA) responsible for speech production in conjunction with the frontal aslant tract (FAT) pathway. SPECT yielded common perfusion abnormalities not only in the fronto–parieto–cerebellar loop, but also in the SMA, IFG and surrounding language-relevant regions. In NIRS sessions during a phonemic verbal fluency task, we found significant word retrieval decline in acute thalamic patients relative to age-matched healthy volunteers. Further, NIRS showed strong correlation between word retrieval and posterior SMA responses. In addition, follow-up NIRS exhibited increased bilateral SMA responses linked to improving word retrieval ability. The findings suggest that cognitive dysfunction may be related to the fronto–parieto–cerebellar loop, while language dysfunction is attributed to the SMA, IFG and language-related brain areas. SMA may contribute to the recovery of word retrieval difficulty and aphasia after thalamic stroke.
关键词： SPECT,hemodynamic response,perfusion,verbal fluency test,thalamic aphasia,FAT: frontal aslant tract,cerebro-cerebellar diaschisis,functional near-infrared spectroscopy (f-NIRS)
更新于2025-09-23 15:19:57
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[Institution of Engineering and Technology 8th Renewable Power Generation Conference (RPG 2019) - Shanghai, China (24-25 Oct. 2019)] 8th Renewable Power Generation Conference (RPG 2019) - Arc Fault Detection and Localization in Photovoltaic Systems Based on Arc Signatures in Low Impedance Paths and Its Path Topology
摘要： Near-infrared spectroscopy (NIRS) has been proposed as a suitable technique for the analysis of cerebral autoregulation as it provides a simpler acquisition methodology and more artifact-free signal. A number of sophisticated wavelet transform methods have recently emerged to quantify the cerebral autoregulation mechanism using NIRS and blood pressure signals. These provide an enhanced partitioning of signal information via the time–frequency plane, which facilitates improved extraction of the components of interest. This area is reviewed, and enhancements to this form of analysis are suggested.
关键词： wavelet transform,Cerebral autoregulation,NIRS
更新于2025-09-23 15:19:57
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Analysing carbon fractions of growing media by near- infrared spectroscopy
摘要： Colonisation of peat based growing media by saprophytic fungi is an increasing problem. One important risk factor for excessive fungal growth is biodegradability of organic matter. Especially hydrolysable carbon seems to be a readily accessible carbon and energy source for these fungi. But established chemical methods to analyse hydrolysable carbon are expensive and time consuming. Near-infrared spectroscopy (NIRS) might be a cheap and fast alternative. The dataset consists of various growing media constituents (peat, green waste compost, composted bark, coco pith, wood fibre) and mixtures of peat with one of the listed peat substitutes. NIR spectra were taken of dried and ground samples using a FT-NIR spectrometer. Various pre-processing methods were applied and PCA and PLS models were calculated. As reference values a) hydrolysable carbon was digested with 0.005 M and 1 M HCl, respectively, and measured by ICP-OES and b) total organic carbon (TOC) and total carbon (TC) were analysed with an elemental analyser. Ergosterol as indicator for fungal biomass was determined after inoculation with Peziza ostracoderma and subsequent incubation for 12 days. Coir pith and wood fibre show a different spectral pattern and were removed as outliers. For the remaining samples good calibration models were obtained for both hydrolysable carbon fractions (R2≥0.9, RPD≥2.8, RER≥10) but neither for TOC nor TC (R2<0.8, RPD<2.5, RER<10). Both fractions of hydrolysable carbon predicted by NIRS are highly correlated to ergosterol content after incubation (r≥0.74). Thus, NIRS is a valuable tool to identify growing media carrying a high risk of excessive fungal colonisation.
关键词： saprophytic fungi,ergosterol,Peziza ostracoderma,NIRS,hydrolysable carbon
更新于2025-09-19 17:15:36