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A multimodal spectroscopic approach is proposed to correlate the mechanical and chemical properties of plastic materials in art and design objects, at both surface and subsurface levels, to obtain information about their conservation state and to monitor their degradation. The approach was used to investigate the photo-oxidation of acrylonitrile butadiene styrene (ABS), a plastic commonly found in many artistic and design applications, using ABS-based LEGO bricks as model samples. The modifications of the chemical and viscoelastic properties of ABS during photoaging were monitored by correlative Brillouin and Raman microspectroscopy (BRaMS), combined with portable and noninvasive broad-range external reflection infrared (IR) spectroscopy and nuclear magnetic resonance (NMR) relaxometry, directly applicable in museums. BRaMS enabled combined measurements of Brillouin light scattering and Raman spectroscopy in a microspectroscopic setup, providing for the coincident probe of the chemical and mechanical changes of ABS at the sample surface. NMR relaxometry allowed for noninvasive measurements of relaxation times and depth profiles which are directly related to the molecular mobility of the material. Complementary chemical information was acquired by external reflection IR spectroscopy. The simultaneous probe of the chemical and mechanical properties by this multimodal spectroscopic approach enabled us to define a decay model of ABS in terms of compositional changes and variation of stiffness and rigidity occurring with photodegradation. The knowledge acquired on LEGO samples has been used to rate the conservation state of ABS design objects noninvasively investigated by external reflection Fourier transform IR spectroscopy and NMR relaxometry offered by the MObile LABoratory (MOLAB) platform of the European Research Infrastructure of Heritage Science. [ABSTRACT FROM AUTHOR]

ABSTRACT: The aim of the study was to enquire to which extend 1H spin-lattice nuclear magnetic resonance (NMR) relaxometry data collected over a broad range of resonance frequencies (from 10 kHz to 10 MHz) have the potential to be used for assessing quality and authenticity of different categories of cheese. The following cheeses were selected mozzarella, processed cheese, pizza cheese, pizza cheese with modified fat phase), low-fat cheese, and long ripened cheese. The cheeses from 3 different production plants and various cheese production batches were used in the study. The samples from each group were subjected to instrumental composition analysis (FoodScan analyzer type 78810, FOSS, Hillerod, Denmark), water activity assessment (Aqualab 4TEV analyzer, type S40001855) and nuclear magnetic resonance relaxation dispersion study (SMARtracer FFC relaxometer, Stelar S.r.l, Italy). The state and dynamics of water present in products as free and bound water largely determines the properties of food products, including cheeses. Nuclear magnetic resonance relaxometry studies of cheese enable to reveal relaxation features characteristic of specific categories of cheese. Consequently, the studies can be treated as a step toward exploiting NMR relaxometry for accessing quality and authenticity of cheese. It was shown that at low resonance frequencies, the lower the moisture, the larger the relaxation rate. The durability and quality of cheeses depend on the presence and condition of water, so it is necessary to find a relationship between the presence, condition and mobility of water in cheeses, to increase and improve the quality and extend the shelf life.

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. The aim of the study was to enquire to which extend 1H spin-lattice nuclear magnetic resonance (NMR) relaxometry data collected over a broad range of resonance frequencies (from 10 kHz to 10 MHz) have the potential to be used for assessing quality and authenticity of different categories of cheese. The following cheeses were selected mozzarella, processed cheese, pizza cheese, pizza cheese with modified fat phase), low-fat cheese, and long ripened cheese. The cheeses from 3 different production plants and various cheese production batches were used in the study. The samples from each group were subjected to instrumental composition analysis (FoodScan analyzer type 78810, FOSS, Hillerod, Denmark), water activity assessment (Aqualab 4TEV analyzer, type S40001855) and nuclear magnetic resonance relaxation dispersion study (SMARtracer FFC relaxometer, Stelar S.r.l , Italy). The state and dynamics of water present in products as free and bound water largely determines the properties of food products, including cheeses. Nuclear magnetic resonance relaxometry studies of cheese enable to reveal relaxation features characteristic of specific categories of cheese. Consequently, the studies can be treated as a step toward exploiting NMR relaxometry for accessing quality and authenticity of cheese. It was shown that at low resonance frequencies, the lower the moisture, the larger the relaxation rate. The durability and quality of cheeses depend on the presence and condition of water, so it is necessary to find a relationship between the presence, condition and mobility of water in cheeses, to increase and improve the quality and extend the shelf life. [ABSTRACT FROM AUTHOR]

Nuclear magnetic resonance (NMR) relaxometry is applied to provide direct measurement of water adsorption in anatomical fractions of corn stover. NMR transverse T2 relaxation time distribution measurements indicate multiple water populations, which vary with anatomical fraction and water adsorption. Measured T2 data are used to calculate thermodynamic properties of Brunauer-Emmet-Teller adsorption theory using a model to estimate mono and bilayer relaxation. T2 data are used directly to determine rotational diffusion correlation times indicating adsorption interaction strength. T1-T2 longitudinal-transverse relaxation time correlation measurements quantify differences in the molecular level structural order of the adsorbate surface water as a function of water activity, i.e. relative humidity or water vapor partial pressure. The T1/T2 ratio provides a measure of the surface energy related to the adsorption strength and surface diffusive mobility of the water adsorbate and differentiates the anatomical fractions. The results indicate that direct measurement of NMR relaxation times can be used to characterize corn stover biomass water adsorption, data relevant to processing and handling considerations. (Length scales from Chundawat et al. (2011)) [ABSTRACT FROM AUTHOR]

Designing of new cement-based materials, suitable for three-dimensional printing applications, requires accurate control of the porosity and strength development. This goal may be achieved by introducing the so-called accelerators in the cement mixture. One such accelerator, used in many commercial products, is calcium nitrate. In the present work, the effect of calcium nitrate on the kinetics of pore evolution and strength development was investigated using low-field nuclear magnetic resonance relaxometry and compressive tests. The presence of calcium nitrate in cement paste accelerates the hydration dynamics immediately after mixing but does not significantly affect the pore structure. Moreover, the presence of calcium nitrate increases the compressive strength at 7 days compared with the simple cement paste but the same compressive strength was reached following 28 days of hydration. [ABSTRACT FROM AUTHOR]

It is a longstanding question whether universality or specificity characterize the molecular dynamics underlying the glass transition of liquids. In particular, there is an ongoing debate to what degree the shape of dynamical susceptibilities is common to various molecular glass formers. Traditionally, results from dielectric spectroscopy and light scattering have dominated the discussion. Here, we show that nuclear magnetic resonance (NMR), primarily field-cycling relaxometry, has evolved into a valuable method, which provides access to both translational and rotational motions, depending on the probe nucleus. A comparison of 1H NMR results indicates that translation is more retarded with respect to rotation for liquids with fully established hydrogen-bond networks; however, the effect is not related to the slow Debye process of, for example, monohydroxy alcohols. As for the reorientation dynamics, the NMR susceptibilities of the structural (α) relaxation usually resemble those of light scattering, while the dielectric spectra of especially polar liquids have a different broadening, likely due to contributions from cross correlations between different molecules. Moreover, NMR relaxometry confirms that the excess wing on the high-frequency flank of the α-process is a generic relaxation feature of liquids approaching the glass transition. However, the relevance of this feature generally differs between various methods, possibly because of their different sensitivities to small-amplitude motions. As a major advantage, NMR is isotope specific; hence, it enables selective studies on a particular molecular entity or a particular component of a liquid mixture. Exploiting these possibilities, we show that the characteristic Cole–Davidson shape of the α-relaxation is retained in various ionic liquids and salt solutions, but the width parameter may differ for the components. In contrast, the low-frequency flank of the α-relaxation can be notably broadened for liquids in nanoscopic confinements. This effect also occurs in liquid mixtures with a prominent dynamical disparity in their components. [ABSTRACT FROM AUTHOR]

Ina Mishra,1,2 Clinton Jones,1,3 Vipulkumar Patel,1,2 Sneha Deodhar,1 David P Cistola1,2 1Nanoparticle Diagnostics Laboratory, Institute for Cardiovascular and Metabolic Diseases, Department of Physiology & Anatomy, University of North Texas Health Science Center, Fort Worth, TX, 76107, USA; 2Center of Emphasis in Diabetes & Metabolism, Department of Biomedical Sciences, Paul L. Foster School of Medicine, Texas Tech University Health Sciences Center El Paso, El Paso, TX, 79905, USA; 3Texas College of Osteopathic Medicine, University of North Texas Health Science Center, Fort Worth, TX, 76107, USA Background: The ability to use frozen biobanked samples from cohort studies and clinical trials is critically important for biomarker discovery and validation. Here we investigated whether plasma and serum water transverse relaxation times (T2) from frozen biobanked samples could be used as biomarkers for metabolic syndrome (MetS) and its underlying conditions, specifically insulin resistance, dyslipidemia, and subclinical inflammation. Methods: Plasma and serum aliquots from 44 asymptomatic, non-diabetic human subjects were biobanked at –80°C for 7–9 months. Water T2 measurements were recorded at 37°C on 50 µL of unmodified plasma or serum using benchtop nuclear magnetic resonance relaxometry. The T2 values for freshly drawn and once-frozen-thawed (“frozen”) samples were compared using Huber M-values (M), Lin concordance correlation coefficients (ρc), and Bland–Altman plots. Water T2 values from frozen plasma and serum samples were compared with >130 metabolic biomarkers and analyzed using multi-variable linear/logistic regression and ROC curves. Results: Frozen plasma water T2 values were highly correlated with fresh (M=0.94, 95% CI 0.89, 0.97) but showed a lower level of agreement (ρc=0.74, 95% CI 0.62, 0.82) because of an average offset of –5.6% (−7.1% for serum). Despite the offset, frozen plasma water T2 was strongly correlated with markers of hyperinsulinemia, dyslipidemia, and inflammation and detected these conditions with 89% sensitivity and 91% specificity (100%/63% for serum). Using optimized cut points, frozen plasma and serum water T2 detected hyperinsulinemia, dyslipidemia, and inflammation in 23 of 44 subjects, including nine with an early stage of metabolic dysregulation that did not meet the clinical thresholds for prediabetes or MetS. Conclusion: Plasma and serum water T2 values from once-frozen-thawed biobanked samples detect metabolic dysregulation with high sensitivity and specificity. However, the cut points for frozen biobanked samples must be calibrated independent of those for freshly drawn plasma and serum. Keywords: metabolic syndrome, insulin resistance, hyperinsulinemia, dyslipidemia, inflammation, nuclear magnetic resonance relaxometry, metabolic health screening, diabetes prevention

Abstract Background Metabolic syndrome is a cluster of abnormalities that increases the risk for type 2 diabetes and atherosclerosis. Plasma and serum water T2 from benchtop nuclear magnetic resonance relaxometry are early, global and practical biomarkers for metabolic syndrome and its underlying abnormalities. In a prior study, water T2 was analyzed against ~ 130 strategically selected proteins and metabolites to identify associations with insulin resistance, inflammation and dyslipidemia. In the current study, the analysis was broadened ten-fold using a modified aptamer (SOMAmer) library, enabling an unbiased search for new proteins correlated with water T2 and thus, metabolic health. Methods Water T2 measurements were recorded using fasting plasma and serum from non-diabetic human subjects. In parallel, plasma samples were analyzed using a SOMAscan assay that employed modified DNA aptamers to determine the relative concentrations of 1310 proteins. A multi-step statistical analysis was performed to identify the biomarkers most predictive of water T2. The steps included Spearman rank correlation, followed by principal components analysis with variable clustering, random forests for biomarker selection, and regression trees for biomarker ranking. Results The multi-step analysis unveiled five new proteins most predictive of water T2: hepatocyte growth factor, receptor tyrosine kinase FLT3, bone sialoprotein 2, glucokinase regulatory protein and endothelial cell-specific molecule 1. Three of the five strongest predictors of water T2 have been previously implicated in cardiometabolic diseases. Hepatocyte growth factor has been associated with incident type 2 diabetes, and endothelial cell specific molecule 1, with atherosclerosis in subjects with diabetes. Glucokinase regulatory protein plays a critical role in hepatic glucose uptake and metabolism and is a drug target for type 2 diabetes. By contrast, receptor tyrosine kinase FLT3 and bone sialoprotein 2 have not been previously associated with metabolic conditions. In addition to the five most predictive biomarkers, the analysis unveiled other strong correlates of water T2 that would not have been identified in a hypothesis-driven biomarker search. Conclusions The identification of new proteins associated with water T2 demonstrates the value of this approach to biomarker discovery. It provides new insights into the metabolic significance of water T2 and the pathophysiology of metabolic syndrome.

This review details a large panel of experimental studies (Inelastic Neutron Scattering, Quasi-Elastic Neutron Scattering, Nuclear Magnetic Resonance relaxometry, Pulsed-Gradient Spin-Echo attenuation, Nuclear Magnetic Resonance Imaging, macroscopic diffusion experiments) used recently to probe, over a large distribution of characteristic times (from pico-second up to days), the dynamical properties of water molecules and neutralizing cations diffusing within clay/water interfacial media. The purpose of this review is not to describe these various experimental methods in detail but, rather, to investigate the specific dynamical information obtained by each of them concerning these clay/water interfacial media. In addition, this review also illustrates the various numerical methods (quantum Density Functional Theory, classical Molecular Dynamics, Brownian Dynamics, macroscopic differential equations) used to interpret these various experimental data by analyzing the corresponding multi-scale dynamical processes. The purpose of this multi-scale study is to perform a bottom-up analysis of the dynamical properties of confined ions and water molecules, by using complementary experimental and numerical studies covering a broad range of diffusion times (between pico-seconds up to days) and corresponding diffusion lengths (between Angstroms and centimeters). In the context of such a bottom-up approach, the numerical modeling of the dynamical properties of the diffusing probes is based on experimental or numerical investigations performed on a smaller scale, thus avoiding the use of empirical or fitted parameters.

Abstract This study investigated the effects of rye bran and collagen addition to a Frankfurter-like sausage as partial fat replacement. Sensory descriptive analysis revealed that sausages where 6 g/100 g rye bran was added alone was associated with an undesired stored flavour in both cooked (P < 0.05) and fried (P < 0.01) sausages. Combining rye bran addition (3–5 g/100 g) with collagen addition (1–3 g/100 g) had significant effects on the textural attributes firmness (P < 0.01) and hardness (P < 0.05) of both cooked and fried sausages. Texture profiling analysis corroborated these findings as collagen inclusion had significant effects on texture attributes measured instrumentally. Flavour attributes described as spiciness (P < 0.05) and fried sausage (P < 0.05) were also enhanced in the fried sausages manufactured with collagen. NMR T 2 relaxation measurements revealed that addition of collagen to the recipe resulted in an additional and distinct T 2 water population and thus different intrinsic water-protein interactions in the protein network when collagen protein was added, whereas the collagen addition did not impact the intrinsic microstructure of the sausages when examined by confocal laser scanning microscopy. Industrial relevance Collagen inclusion modified technological and sensory attributes and appears as a promising ingredient for development of fat replacement strategies in the manufacturing of processed meat. Highlights • Partial substitution of fat with rye bran and collagen was investigated in Frankfurter sausages. • Collagen inclusion impacted texture and sensory attributes. • Collagen can assist as a functional ingredient during fat replacement in processed meat. [ABSTRACT FROM AUTHOR]

Background: The ability to use frozen biobanked samples from cohort studies and clinical trials is critically important for biomarker discovery and validation. Here we investigated whether plasma and serum water transverse relaxation times (T2) from frozen biobanked samples could be used as biomarkers for metabolic syndrome (MetS) and its underlying conditions, specifically insulin resistance, dyslipidemia, and subclinical inflammation. Methods: Plasma and serum aliquots from 44 asymptomatic, non-diabetic human subjects were biobanked at –80°C for 7–9 months. Water T2 measurements were recorded at 37°C on 50 µL of unmodified plasma or serum using benchtop nuclear magnetic resonance relaxometry. The T2 values for freshly drawn and once-frozen-thawed ("frozen") samples were compared using Huber M-values (M), Lin concordance correlation coefficients (ρc), and Bland–Altman plots. Water T2 values from frozen plasma and serum samples were compared with >130 metabolic biomarkers and analyzed using multi-variable linear/logistic regression and ROC curves. Results: Frozen plasma water T2 values were highly correlated with fresh (M=0.94, 95% CI 0.89, 0.97) but showed a lower level of agreement (ρc=0.74, 95% CI 0.62, 0.82) because of an average offset of –5.6% (−7.1% for serum). Despite the offset, frozen plasma water T2 was strongly correlated with markers of hyperinsulinemia, dyslipidemia, and inflammation and detected these conditions with 89% sensitivity and 91% specificity (100%/63% for serum). Using optimized cut points, frozen plasma and serum water T2 detected hyperinsulinemia, dyslipidemia, and inflammation in 23 of 44 subjects, including nine with an early stage of metabolic dysregulation that did not meet the clinical thresholds for prediabetes or MetS. Conclusion: Plasma and serum water T2 values from once-frozen-thawed biobanked samples detect metabolic dysregulation with high sensitivity and specificity. However, the cut points for frozen biobanked samples must be calibrated independent of those for freshly drawn plasma and serum. [ABSTRACT FROM AUTHOR]

Water pollution by heavy metal is a major environmental problem. Adsorption is one of the most used and promising heavy metal removal techniques. The development and evaluation of new adsorbents is thus an important topic. Some heavy metal ions – like Cu 2+ , Mn 2+ , Cr 3+ … – are paramagnetic and known to affect the Nuclear Magnetic Resonance (NMR) relaxation times T 1 and T 2 of water protons in aqueous solutions. These relaxation times can be used to evaluate the paramagnetic ion concentration in solution. For the adsorption of Cu 2+ on activated alumina, we show, after a comparison with conventional methods, that NMR T 2 relaxometry can be used to perform kinetics study and obtain a Langmuir isotherm. The T 2 relaxometric experiment is performed at 0.47 T directly in an NMR tube with 350 µl of solution and 45 mg of adsorbent. For the kinetics study, a single tube is used since the measurement is nondestructive. The NMR experiments allow to determine a maximum Cu 2+ adsorption capacity q max  = 4.32 mg Cu /g Al2O3 and an equilibrium adsorption constant K  = 0.61 mM −1 . T 1 based relaxometry can also be used to evaluate the amount of Cu 2+ adsorbed on alumina, directly on the wet sorbent. Even if it is limited to paramagnetic heavy metal ion and necessitates rather high metal concentration, NMR relaxometry could become an interesting additional tool for the study of heavy metal adsorption. [ABSTRACT FROM AUTHOR]

The aim of this work is to evaluate the potentiality of a multi-technique nondestructive approach for characterizing the state of conservation of precious bookbindings. In particular, the bookbinding of an ancient book dating back nineteenth century was inspected by infrared thermography, near-infrared reflectography and transmittography, digital speckle photography, holographic interferometry, and proton magnetic resonance relaxometry. Data were processed by different and innovative methodologies, among which, a calibration procedure of the camera for correlation analyses based on specklegrams. The results were compared, showing a promising synergy for the diagnostic purposes, on the basis of the relationship between structure, properties, and uses of the analyzed materials. [ABSTRACT FROM AUTHOR]

The complexity of hydrocarbon reservoirs, comprising numerous moulds, vugs, fractures and channel porosity, requires a specific set of methods to be used in order to obtain plausible petrophysical information. Both computed microtomography (μCT) and nuclear magnetic resonance (NMR) are nowadays commonly utilized in pore space investigation. The principal aim of this paper is to propose an alternative, quick and easily executable approach, enabling a thorough understanding of the complicated interiors of the carbonate hydrocarbon reservoir rocks. Highly porous and fractured Zechstein bioclastic packstones from the Brońsko Reef, located in West Poland were studied. Having examined 20 thin sections coming from two different well bores, 10 corresponding core samples were subjected to both μCT and NMR experiments. After a preliminary μCT-based image analysis, 9.4 [T] high-field zero echo time (ZTE) imaging, using a very short repetition time (RT) of 2 [μs] was conducted. Taking into consideration the risk of internal gradients' generation, the reliability of ZTE was verified by 0.6 [T] Single Point Imaging (SPI), during which such a phenomenon is much less probable. Both narrow channels and fractures of different apertures appeared to be common within the studied rocks. Their detailed description was therefore undertaken based on an additional tool – the spatially-resolved 0.05 [T] T2 profiling. According to the obtained results, ZTE seems to be especially suitable for studying porous and fractured carbonate rocks, as little disturbance to the signal appears. This can be confirmed by the SPI, indicating the negligible impact of the internal gradients on the registered ZTE images. Both NMR imaging and μCT allowed for locating the most porous intervals including well-developed mouldic porosity, as well as the contrasting impermeable structures, such as the stylolites and anhydrite veins. The 3D low-field profiling, in turn, showed the fracture aperture variations and contributed to the recognition of pore geometry. Analogously, the authors believe that such a spatially-resolved profiling could also be successfully implemented to study unconventional reservoirs. Finally, it has been concluded that although it is possible to investigate the connectivity of a given pore space solely using μCT, a detailed labeling process might turn out to be too time consuming and require a sound experience in that field. Therefore it is proposed to follow a preliminary μCT modeling by the direct and non-invasive set of NMR experiments. [ABSTRACT FROM AUTHOR]

As a consequence of carbonate pore system ambiguity, only two basic carbonate textures, i.e. mudstone and completely contrasting grainstone have thus far been found to be separable using Nuclear Magnetic Resonance (NMR) relaxometry. Therefore, a new methodology of NMR-derived carbonate facies and diagenetic alteration recognition was prepared and experimentally launched. As many ancient carbonates have often experienced a meteoric exposure stage, this approach focuses on such conditions. Especially the paleoreef carbonate reservoirs are of the main interest of the authors. The Wielichowo Reef (western Poland), developed on an uplifted pre-Zechstein horst structure - the Wolsztyn Ridge - was chosen for the study object. The reef is representative for its region because it is characterized by both high textural and diagenetic variability, often repeatable in case of other objects present on the Wolsztyn Ridge. Consequently, twenty one Zechstein Limestone (Ca1) carbonate core samples from the chosen object were qualitatively studied using a low-field, 50 [mT] NMR spectrometer. Corresponding thin section samples were carefully investigated using both polarizing and electron microscopy, cathodoluminescence and sample staining to obtain a full overview of their petrography and enable further comparisons between NMR and the remaining data. As shown by the obtained results, various carbonate facies can be distinguished on the basis of few criteria. These include: (1) the changeability of the signal's amplitude, (2) the values of clay-bound (MCBW), capillary (BVI) and freely moving (FFI) water, and (3) – the width of the main T2 peak , defined as the first peak occurring directly after the BVI, whose average amplitude exceeds or equals at least 75% of the maximal average amplitude encountered within MCBW or BVI systems. Similarly, it seems possible to separate dissolution vugs from other pore systems. The wider the main peak , the higher the probability of finding irregularly-shaped vugs, as diameter size variances account for elevating signal's amplitude, corresponding to various relaxation times. Furthermore, fractures and increased cementation have a significant impact on final T2 distribition's appearance, as well - hence making the low-field NMR an invaluable tool in the evaluation of carbonate reservoirs influenced by the meteoric exposure. [ABSTRACT FROM AUTHOR]

Fricke infused gel matrices offer several features making them suitable for dosimetric applications; among these there are tissue equivalence, low cost and ease of preparation. Their nuclear magnetic resonance (NMR) relaxation properties can be used as a radiation detector for the dosimetry of beams used in cancer therapy. In recent years neutron capture therapy has been resumed for the treatment of various types of cancer and it requires three-dimensional mapping of the neutron fields. In this work, we investigated this particular application through NMR relaxometry and MR imaging of Fricke gels exposed to neutrons. We analyzed both the R 1 and R 2 relaxation rates, which relate to the longitudinal T 1 and transversal T 2 relaxation times. In particular, we found that the relaxation rate R 2 does not depend on the neutron fluence, whereas the relaxation rate R 1 increases linearly with the fluence. The magnetic resonance imaging acquisitions showed that T 1 -weighted images allow the characterization of samples exposed to different neutron fluences. [ABSTRACT FROM AUTHOR]

This work describes the characterization of various Fricke-Agarose-Xylenol gels (FXG) dosimeters using NMR relaxometry and MRI analysis. Using X-rays from a clinical linear accelerator (LINAC), the gels were irradiated in the dose range from 0 Gy to 20 Gy. The photon sensitivity of the FXGs was measured in terms of NMR relaxation rates; its dependence on radiation dose was determined as a function of ferrous ammonium sulfate contents (from 0.5 mM to 5 mM). Furthermore, the stability of the NMR signal was monitored over several days after irradiation. These measurements were aided by Magnetic Resonance Imaging (MRI) scans which allowed three-dimensional (3D) dose mapping. In order to maximize the MRI response, a systematic study was performed to optimize acquisition sequences and parameters. In particular, we analyzed the dependence of MRI signal on the repetition time (TR) and on the inversion time (TI) using inversion recovery sequences. The results are reported and discussed from the point of view of the dosimeter use in clinical radiotherapy. This work highlights that the optimization of additive content inside gel matrix is fundamental for optimizing photon sensitivity of these detectors. [ABSTRACT FROM AUTHOR]

The influence of laser and non-coherent irradiation on the state of oil components has been studied at wavelengths of 630 and 1825 nm, respectively. New results reflecting changes in structural–dynamic parameters of the molecular motion as a function of exposure time have been obtained. The variations of NMR parameters during NIR irradiation of an oil sample prepared with the addition of paraffin (docosane) seem to be connected with "washing out" of these nanodimensional structures and can be explained theoretically in terms of the phenomenological description of the energy-level population behavior. The method of NMR relaxometry used in parallel with laser and non-coherent radiation in the NIR spectral region has been shown to enable one to readily determine oil components that are difficult to estimate by conventional techniques. [ABSTRACT FROM AUTHOR]

Water mobility within the porous network of dense clay sediments was investigated over a broad dynamical range by using 2H nuclear magnetic resonance spectroscopy. Multi-quanta 2H NMR spectroscopy and relaxation measurements were first performed to identify the contributions of the various relaxation mechanisms monitoring the time evolution of the nuclear magnetisation of the confined heavy water. Secondly, multi-quanta spin-locking NMR relaxation measurements were then performed over a broad frequency domain, probing the mobility of the confined water molecules on a time-scale varying between microseconds and milliseconds. Thirdly, 1H NMR pulsed-gradient spin-echo attenuation experiments were performed to quantify water mobility on a time-scale limited by the NMR transverse relaxation time of the confined NMR probe, typically a few milliseconds. Fourthly, the long living quantum state of the magnetisation of quadrupolar nuclei was exploited to probe a two-time correlation function at a time-scale reaching one second. Finally, magnetic resonance imaging measurements allow probing the same dynamical process on time-scales varying between seconds and several hours. In that context, multi-scale modelling is required to interpret these NMR measurements and extract information on the influences of the structural properties of the porous network on the apparent mobility of the diffusing water molecules. That dual experimental and numerical approach appears generalizable to a large variety of porous networks, including zeolites, micelles and synthetic or biological membranes. [ABSTRACT FROM AUTHOR]

Background: The ability to use frozen biobanked samples from cohort studies and clinical trials is critically important for biomarker discovery and validation. Here we investigated whether plasma and serum water transverse relaxation times (T 2 ) from frozen biobanked samples could be used as biomarkers for metabolic syndrome (MetS) and its underlying conditions, specifically insulin resistance, dyslipidemia, and subclinical inflammation., Methods: Plasma and serum aliquots from 44 asymptomatic, non-diabetic human subjects were biobanked at -80°C for 7-9 months. Water T 2 measurements were recorded at 37°C on 50 µL of unmodified plasma or serum using benchtop nuclear magnetic resonance relaxometry. The T 2 values for freshly drawn and once-frozen-thawed ("frozen") samples were compared using Huber M-values (M), Lin concordance correlation coefficients (ρ c ), and Bland-Altman plots. Water T 2 values from frozen plasma and serum samples were compared with >130 metabolic biomarkers and analyzed using multi-variable linear/logistic regression and ROC curves., Results: Frozen plasma water T 2 values were highly correlated with fresh (M=0.94, 95% CI 0.89, 0.97) but showed a lower level of agreement (ρ c =0.74, 95% CI 0.62, 0.82) because of an average offset of -5.6% (-7.1% for serum). Despite the offset, frozen plasma water T 2 was strongly correlated with markers of hyperinsulinemia, dyslipidemia, and inflammation and detected these conditions with 89% sensitivity and 91% specificity (100%/63% for serum). Using optimized cut points, frozen plasma and serum water T 2 detected hyperinsulinemia, dyslipidemia, and inflammation in 23 of 44 subjects, including nine with an early stage of metabolic dysregulation that did not meet the clinical thresholds for prediabetes or MetS., Conclusion: Plasma and serum water T 2 values from once-frozen-thawed biobanked samples detect metabolic dysregulation with high sensitivity and specificity. However, the cut points for frozen biobanked samples must be calibrated independent of those for freshly drawn plasma and serum., Competing Interests: Disclosure The University of North Texas Health Science Center, Fort Worth has applied for a patent related to the methods described in this study, with David P Cistola and Michelle D Robinson as co-inventors. The authors report no other conflicts of interest in this work.