Visualisation of sampling error effects in near infrared analysis—comparison between Petri dish, roll bottle and spiral sampler

TOS forum ◽  
2014 ◽  
Vol 2013 (1) ◽  
pp. 22
Author(s):  
Marie Sørensen ◽  
Anders Larsen ◽  
Kim Esbensen
Keyword(s):  
Near Infrared ◽  
Sampling Error ◽  
Petri Dish ◽  
Infrared Analysis

Single-Kernel near Infrared Analysis of Bulk Wheat Heterogeneity—A Theory of Sampling Reference Study

NIR news ◽  
2008 ◽  
Vol 19 (1) ◽  
pp. 4-7 ◽  
Author(s):  
Erik Tønning ◽  
Lars Nørgaard ◽  
Søren B. Engelsen ◽  
Lene Pedersen ◽  
Kim H. Esbensen
Keyword(s):  
Near Infrared ◽  
Infrared Analysis ◽  
Theory Of Sampling

scholarly journals Proxy Measures and Novel Strategies for Estimating Nitrogen Utilisation Efficiency in Dairy Cattle

Animals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 343
Author(s):  
Anna Lavery ◽  
Conrad Ferris
Keyword(s):  
Near Infrared ◽  
Isotope Analysis ◽  
Strong Relationship ◽  
Nitrogen Isotope ◽  
Invasive Technique ◽  
Infrared Analysis ◽  
Resonance Spectroscopy ◽  
Dietary Nitrogen ◽  
Nitrogen Utilisation ◽  
Utilisation Efficiency

The efficiency with which dairy cows convert dietary nitrogen (N) to milk N is generally low (typically 25%). As a result, much of the N consumed is excreted in manure, from which N can be lost to the environment. Therefore there is increasing pressure to reduce N excretion and improve N use efficiency (NUE) on dairy farms. However, assessing N excretion and NUE on farms is difficult, thus the need to develop proximate measures that can provide accurate estimates of nitrogen utilisation. This review examines a number of these proximate measures. While a strong relationship exists between blood urea N and urinary N excretion, blood sampling is an invasive technique unsuitable for regular herd monitoring. Milk urea N (MUN) can be measured non-invasively, and while strong relationships exist between dietary crude protein and MUN, and MUN and urinary N excretion, the technique has limitations. Direct prediction of NUE using mid-infrared analysis of milk has real potential, while techniques such as near-infrared spectroscopy analysis of faeces and manure have received little attention. Similarly, techniques such as nitrogen isotope analysis, nuclear magnetic resonance spectroscopy of urine, and breath ammonia analysis may all offer potential in the future, but much research is still required.

scholarly journals A method to correct sampling ghosts in historic near-infrared Fourier Transform Spectrometer (FTS) measurements

2013 ◽  
Vol 6 (2) ◽  
pp. 3545-3579 ◽  
Author(s):  
S. Dohe ◽  
V. Sherlock ◽  
F. Hase ◽  
M. Gisi ◽  
J. Robinson ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Near Infrared ◽  
Sampling Error ◽  
Total Carbon ◽  
Sampling Errors ◽  
Step Procedure ◽  
Residual Difference ◽  
Correction Scheme ◽  
Parent Ratio ◽  
Good Agreement

Abstract. The Total Carbon Column Observing Network (TCCON) has been established to provide ground-based remote sensing measurements of the column-average dry air mole fractions of key greenhouse gases. To ensure the network wide consistency, biases between Fourier Transform spectrometers at different sites have to be well controlled. In this study we investigate a fundamental correction scheme for errors in the sampling of the interferogram. This is a two-step procedure in which the laser sampling error (LSE) is quantified using a subset of suitable interferograms and then used to resample all the interferograms in the timeseries. Timeseries of measurements acquired at the TCCON sites Izaña and Lauder are used to demonstrate the method. At both sites the sampling error histories show changes in LSE due to instrument interventions. Estimated LSE are in good agreement with sampling errors inferred from lamp measurements of the ghost to parent ratio (Lauder). The LSE introduce retrieval biases which are minimised when the interferograms are resampled. The original timeseries of Xair and XCO2 at both sites show discrepancies of 0.2–0.5% due to changes in the LSE associated with instrument interventions or changes in the measurement sample rate. After resampling discrepancies are reduced to 0.1% at Lauder and 0.2% at Izaña. In the latter case, coincident changes in interferometer alignment may also contribute to the residual difference.

Fundamental baseline variations in aqueous near-infrared analysis

1999 ◽  
Vol 394 (2-3) ◽  
pp. 135-147 ◽  
Author(s):  
Alexey Heiman ◽  
Stuart Licht
Keyword(s):  
Near Infrared ◽  
Infrared Analysis

scholarly journals Detection of early neoplasia in Barrett’s esophagus using lectin-based near-infrared imaging: an ex vivo study on human tissue

Endoscopy ◽  
2018 ◽  
Vol 50 (06) ◽  
pp. 618-625 ◽  
Author(s):  
André Neves ◽  
Massimiliano Di Pietro ◽  
Maria O’Donovan ◽  
Dale Waterhouse ◽  
Sarah Bohndiek ◽  
...  
Keyword(s):  
Barrett’S Esophagus ◽  
Barrett's Esophagus ◽  
Near Infrared ◽  
Infrared Imaging ◽  
Ex Vivo ◽  
Sampling Error ◽  
Nir Light ◽  
Nir Imaging ◽  
Nir Fluorescence ◽  
Nir Dye

Abstract Background and study aims Endoscopic surveillance for Barrett’s esophagus (BE) is limited by long procedure times and sampling error. Near-infrared (NIR) fluorescence imaging minimizes tissue autofluorescence and optical scattering. We assessed the feasibility of a topically applied NIR dye-labeled lectin for the detection of early neoplasia in BE in an ex vivo setting. Methods Consecutive patients undergoing endoscopic mucosal resection (EMR) for BE-related early neoplasia were recruited. Freshly collected EMR specimens were sprayed at the bedside with fluorescent lectin and then imaged. Punch biopsies were collected from each EMR under NIR light guidance. We compared the fluorescence intensity from dysplastic and nondysplastic areas within EMRs and from punch biopsies with different histological grades. Results 29 EMR specimens were included from 17 patients. A significantly lower fluorescence was found for dysplastic regions across whole EMR specimens (P < 0.001). We found a 41 % reduction in the fluorescence of dysplastic compared to nondysplastic punch biopsies (P < 0.001), with a sensitivity and specificity for dysplasia detection of 80 % and 82.9 %, respectively. Conclusion Lectin-based NIR imaging can differentiate dysplastic from nondysplastic Barrett’s mucosa ex vivo.

Sign in / Sign up

Export Citation Format

Share Document