182 research outputs found
Analysis of Scotch Whisky by 1H NMR and chemometrics yields insight into its complex chemistry
Measuring change
A change in the reporting of HbA1c is
being adopted globally,
including in Australia.
It's anticipated that this
change will, among other
things, make it easier for doctors
to educate their patients
about the importance of glycaemic
control. However, to
understand how this change
will help in practice, it's useful
to firstly understand what
HbA1c is and to know something
of the history of how
laboratories have measured
the HbA1c assay
Size and shape analysis of error-prone shape data
We consider the problem of comparing sizes and shapes of objects when landmark data are prone to measurement error. We show that naive implementation of ordinary Procrustes analysis that ignores measurement error can compromise inference. To account for measurement error, we propose the conditional score method for matching configurations, which guarantees consistent inference under mild model assumptions. The effects of measurement error on inference from naive Procrustes analysis and the performance of the proposed method are illustrated via simulation and application in three real data examples. Supplementary materials for this article are available online
Complementary Ionization Techniques for the Analysis of Scotch Whisky by High Resolution Mass Spectrometry
Fourier
transform mass spectrometry (FTMS) is widely used to characterize
the chemical complexity of mixtures, such as natural organic matter
(NOM), petroleum, and agri-food products (including Scotch whisky).
Although electrospray ionization (ESI) is by far the most widely used
ionization source in these studies, other ionization techniques are
available and may offer complementary information. In a recent study,
we found matrix free laser desorption/ionization (LDI) to be effective
for the analysis of Suwannee river fulvic acid (SRFA), and to provide
complementary chemical insights. In this study, LDI along with atmospheric
pressure photoionization (APPI) and atmospheric pressure chemical
ionization (APCI) were compared to ESI for the analysis of Scotch
whisky. High mass accuracy (54 ppb, mean) allowed for the assignment
of 86% of peaks, with 3993 unique molecular formulas identified from
four representative samples analyzed. All four ionization techniques,
performed in negative mode, identified thousands of formulas. Many
were unique to each ionization source, while 699 formulas were common
to all techniques. Ions were identified in both deprotonated and radical
anion forms. Our study highlights the importance of a multi-ionization
source approach; we recommend that analysis of complex mixtures, especially
novel ones, should not be limited solely to ESI
Through-container, extremely low concentration detection of multiple chemical markers of counterfeit alcohol using a handheld SORS device
Major food adulteration incidents occur with alarming frequency and are episodic, with the latest incident, involving the adulteration of meat from 21 producers in Brazil supplied to 60 other countries, reinforcing this view. Food fraud and counterfeiting involves all types of foods, feed, beverages, and packaging, with the potential for serious health, as well as significant economic and social impacts. In the spirit drinks sector, counterfeiters often ‘recycle’ used genuine packaging, or employ good quality simulants. To prove that suspect products are non-authentic ideally requires accurate, sensitive, analysis of the complex chemical composition while still in its packaging. This has yet to be achieved. Here, we have developed handheld spatially offset Raman spectroscopy (SORS) for the first time in a food or beverage product, and demonstrate the potential for rapid in situ through-container analysis; achieving unequivocal detection of multiple chemical markers known for their use in the adulteration and counterfeiting of Scotch whisky, and other spirit drinks. We demonstrate that it is possible to detect a total of 10 denaturants/additives in extremely low concentrations without any contact with the sample; discriminate between and within multiple well-known Scotch whisky brands, and detect methanol concentrations well below the maximum human tolerable level
Advanced solvent signal suppression for the acquisition of 1D and 2D NMR spectra of Scotch Whisky
Comparative analysis of the surface exposed proteome of two canine osteosarcoma cell lines and normal canine osteoblasts
BACKGROUND: Osteosarcoma (OSA) is the most common primary bone tumor of dogs and carries a poor prognosis despite aggressive treatment. An improved understanding of the biology of OSA is critically needed to allow for development of novel diagnostic, prognostic, and therapeutic tools. The surface-exposed proteome (SEP) of a cancerous cell includes a multifarious array of proteins critical to cellular processes such as proliferation, migration, adhesion, and inter-cellular communication. The specific aim of this study was to define a SEP profile of two validated canine OSA cell lines and a normal canine osteoblast cell line utilizing a biotinylation/streptavidin system to selectively label, purify, and identify surface-exposed proteins by mass spectrometry (MS) analysis. Additionally, we sought to validate a subset of our MS-based observations via quantitative real-time PCR, Western blot and semi-quantitative immunocytochemistry. Our hypothesis was that MS would detect differences in the SEP composition between the OSA and the normal osteoblast cells. RESULTS: Shotgun MS identified 133 putative surface proteins when output from all samples were combined, with good consistency between biological replicates. Eleven of the MS-detected proteins underwent analysis of gene expression by PCR, all of which were actively transcribed, but varied in expression level. Western blot of whole cell lysates from all three cell lines was effective for Thrombospondin-1, CYR61 and CD44, and indicated that all three proteins were present in each cell line. Semi-quantitative immunofluorescence indicated that CD44 was expressed at much higher levels on the surface of the OSA than the normal osteoblast cell lines. CONCLUSIONS: The results of the present study identified numerous differences, and similarities, in the SEP of canine OSA cell lines and normal canine osteoblasts. The PCR, Western blot, and immunocytochemistry results, for the subset of proteins evaluated, were generally supportive of the mass spectrometry data. These methods may be applied to other cell lines, or other biological materials, to highlight unique and previously unrecognized differences between samples. While this study yielded data that may prove useful for OSA researchers and clinicians, further refinements of the described techniques are expected to yield greater accuracy and produce a more thorough SEP analysis
Cost estimation for remanufacture with limited and uncertain information using case based reasoning
Assessing products prior to remanufacture is an important part of the remanufacturing
process, ensuring that unsuitable cores are removed at an early stage to avoid
unnecessary processing. In particular, understanding the economic cost of
remanufacturing a product can be an important aspect of the assessment, especially for
businesses operating in low volumes and on high value products, where the risk
associated with unexpected costs or failure to complete remanufacture are much
greater. Estimating these costs can however be difficult, as important information
required to make a prediction is often uncertain, such as the product design, its
condition and also the understanding of the resource requirements for remanufacture.
Within this research a method has been developed to estimate the economic cost and
risks of conducting a remanufacturing activity to a product when information is
uncertain. Summation of the individual activities can then be conducted to
determine the economic cost and risks of the entire remanufacturing process.
The method utilises a combination of case based reasoning and probability theory to
identify similarities between historical data records and the product under assessment,
to predict the cost and risks of remanufacture. In particular this method enables cost
estimation when important product information is missing including the manufacturer,
model or condition. Additionally estimates can be made when exact historical
information is not present, which can be useful to business remanufacturing
bespoke or rare products. The method is then implemented within a service
oriented architecture and functionally demonstrated using an example of an
independent wind turbine gearbox remanufacturer
An evaluation of section 1 of the Offensive Behaviour at Football and Threatening Communications (Scotland) Act 2012
A mixed methods evaluation of a legislation introduced by the Scottish Government to tackle sectarian and other offensive behaviours at regulated fotoball matche
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