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The evaluation of an oil's oxidation status during industrial production is highly important for monitoring the oil's purity and nutritional value during production, transportation, storage, and cooking. The oil and food industry is seeking a real-time, non-destructive, rapid, robust, and low-cost sensor for nutritional oil's material characterization. Towards this goal, a 1H LF-NMR relaxation sensor application based on the chemical and structural profiling of non-oxidized and oxidized oils was developed. This study dealt with a relatively large-scale oil oxidation database, which included crude data of a 1H LF-NMR relaxation curve, and its reconstruction into T1 and T2 spectral fingerprints, self-diffusion coefficient D, and conventional standard chemical test results. This study used a convolutional neural network (CNN) that was trained to classify T2 relaxation curves into three ordinal classes representing three different oil oxidation levels (non-oxidized, partial oxidation, and high level of oxidation). Supervised learning was used on the T2 signals paired with the ground-truth labels of oxidation values as per conventional chemical lab oxidation tests. The test data results (not used for training) show a high classification accuracy (95%). The proposed AI method integrates a large training set, an LF-NMR sensor, and a machine learning program that meets the requirements of the oil and food industry and can be further developed for other applications. [ABSTRACT FROM AUTHOR]

The food quality of edible oils is dependent on basic chemical and structural changes that can occur by oxidation during preparation and storage. A rapid and efficient analytical method of the different steps of oil oxidation is described using a time-domain nuclear magnetic resonance (TD-NMR) sensor for measuring signals related to the chemical and physical properties of the oil. The degree of thermal oxidation of edible oils at 80 °C was measured by the conventional methodologies of peroxide and aldehyde analysis. Intact non-modified samples of the same oils were more rapidly analyzed for oxidation using a TD-NMR sensor for 2D T1-T2 and self-diffusion (D) measurements. A good linear correlation between the D values and the conventional chemical analysis was achieved, with the highest correlation of R2 = 0.8536 for the D vs. the aldehyde concentrations during the thermal oxidation of poly-unsaturated linseed oils, the oil most susceptible to oxidation. A good correlation between the D and aldehyde levels was also achieved for all the other oils. The possibility to simplify and minimize the time of oxidative analysis using the TD NMR sensors D values is discussed as an indicator of the oil's oxidation quality, as a rapid and accurate methodology for the oil industry. [ABSTRACT FROM AUTHOR]

Food safety monitoring is highly important due to the generation of unhealthy components within many food products during harvesting, processing, storage, transportation and cooking. Current technologies for food safety analysis often require sample extraction and the modification of the complex chemical and morphological structures of foods, and are either time consuming, have insufficient component resolution or require costly and complex instrumentation. In addition to the detection of unhealthy chemical toxins and microbes, food safety needs further developments in (a) monitoring the optimal nutritional compositions in many different food categories and (b) minimizing the potential chemical changes of food components into unhealthy products at different stages from food production until digestion. Here, we review an efficient methodology for overcoming the present analytical limitations of monitoring a food's composition, with an emphasis on oxidized food components, such as polyunsaturated fatty acids, in complex structures, including food emulsions, using compact instruments for simple real-time analysis. An intelligent low-field proton NMR as a time domain (TD) NMR relaxation sensor technology for the monitoring of T2 (spin-spin) and T1 (spin-lattice) energy relaxation times is reviewed to support decision-making by producers, retailers and consumers in regard to food safety and nutritional value during production, shipping, storage and consumption. [ABSTRACT FROM AUTHOR]

Linseed contains high levels of polyunsaturated fatty acids (PUFA), such as α‐linolenic acid (> 50% ALA‐18:3), that are naturally protected against thermal oxidation by their encapsulation within linseed oil bodies (OB) by multiple components including antioxidant proteins and mucilage emulsifying agents. Linseed OB emulsions (LSE) can be produced by grinding linseed seeds, adding water, adjusting pH, and sonication. This is a process that can encapsulate externally added PUFA to minimize their thermal oxidation, as it does for the intrinsic ALA PUFA. Fish oil (FO) encapsulation into this LSE platform to form linseed fish oil emulsions (LSFE) offers the possibility of a nutritive delivery system of the biologically essential FO PUFA eicosapentaenoic acid and docosahexaenoic acid. In this study, 1H low‐field nuclear magnetic resonance (LF‐NMR) is used to characterize LSE's and LSFE's chemical and structural properties as well as their stability and changes under thermal oxidation (55 °C for 96 hours). 1H LF‐NMR data processing was developed to generate one‐dimensional (1D) T1 (spin–lattice), 1D T2 (spin–spin), and 2D (T1 vs. T2) relaxation time spectra that can characterize OB emulsions and monitor their time domain fingerprints (spectrum peaks) of chemical and structural changes during the oxidation process. The 1H LF‐NMR analysis were further supported and correlated with conventional peroxide value test, self‐diffusion, droplet size distribution, zeta potential estimation of surface stability, and gas chromatography–mass spectrometry analysis of fatty acid profile changes under thermal oxidation conditions. The 1D and 2D LF‐NMR relaxation spectra showed that the LSE and LSFE did not suffer intense oxidation process, due to PUFA assembly in OB oxidative protection. These results were further confirmed by the supportive analytical methodologies. The results of this study demonstrate the efficacy of 1H LF‐NMR methodology to monitor PUFA's rich oil and emulsion thermal oxidation. [ABSTRACT FROM AUTHOR]

Omega‐3 polyunsaturated fatty acid (PUFA)‐rich linseed oil (LSO) is an important component in biological systems, foods, and many other industrial products. In recent years, LSO has attracted increased attention in the field of functional foods, which has highlighted its facile susceptibility to aging by autoxidation. Common colorimetric and a long list of spectral methodologies have been used to follow after and predict LSO shelf life's quality, especially in regards to aging by autoxidation. These standard methodologies are nevertheless limited, because of the complexity of the LSO's chemical and physical changes. The goal of the present study is to develop a sensorial 1H LF‐NMR energy relaxation time application based on monitoring primary chemical and structural changes occurring with time and temperature during oxidative thermal stress for better and rapid evaluation of LSO's aging process. Using 1H low‐field NMR, the different T2 times of energy relaxations due to spin–spin coupling, and proton motion/mobility of LSO molecular segments were monitored. As previously reported, we characterized the chemical and structural changes in all phases of the autoxidation aging process. Starting from the initiation phase (abstraction of hydrogen radical, fatty acid chain rearrangement, and oxygen uptake yielding hydroperoxides products), through to the propagation phase (chain reactions resulting in tail cleavage to form alkoxy radicals, and alpha, beta‐unsaturated aldehydes formation), and a termination phase (cross linking and production of polymerization end products). The 1H LF NMR transverse relaxation approach, monitors both the covalent bond's strong forces (100–400 kJ mol−1) in LSO oxidative aging decomposition, as well as secondary relatively weak interactive forces by hydrogen bonds (~70 kJ mol−1), and electrostatic bonds (0–50 kJ mol−1) contributing to secondary crosslinking interactions leading to a LSO viscous gel of polymerized products in the termination phase. In the present paper, we show that LSO tail segments mobility in terms of T2 multi‐exponential energy relaxation time decays, generated by data reconstruction of 1H transverse relaxation components are providing a clear, sharp, and informative understanding of LSO sample's autoxidation aging processes. To support T2 time domain data analysis, we used data from high‐field band‐selective 1H NMR pulse excitation for quantification of hydroperoxides and aldehydes of the same LSO samples treated under the same thermal conditions (25, 40, 60, 80, 100, 120 °C) with pumped air for 168 hours. Peroxide value, viscosity, and self‐diffusion analyses, as well as fatty acids profile and by‐products determined by GC–MS on the same samples were carried out, and correlated with the LSO tail T2 energy relaxation time results. From these results, it is postulated that selective determination of LSO tail T2 time domain can be used as a rapid evaluation marker for following omega‐3 PUFA‐rich oils oxidative aging process within industrial and commercial products. [ABSTRACT FROM AUTHOR]

Polyunsaturated fatty acids (PUFA) are components of many commercial products such as edible oils, foods, cosmetics, medication, and in biological systems such as phospholipids of cellular membranes. Although PUFA aggregates are important functional components, they are also related to system degradation, because PUFA are susceptible to oxidation via their multiple double bonds and allylic carbons. Current technologies are not effective in characterizing the morphological and chemical structural domains of saturated, monounsaturated fatty acids (MUFA) and PUFA materials, or how the morphological structures of fatty acids, at the mesomolecular, nanomolecular, and molecular levels, affect their oxidation mechanisms. In this article, the 1H low‐field (LF) NMR energy relaxation time technology is proposed as a tool to analyze PUFA oils undergoing thermal oxidation. This technology generates two‐dimensional (2D) chemical and morphological spectra using a primal‐dual interior method for the convex objectives (PDCO) optimization solver for computational processing of the energy relaxation time signals T1 (spin–lattice) and T2 (spin–spin). The 2D graphical maps of T1 vs. T2 generated for butter, rapeseed oil, soybean oil, and linseed oil show that the different degrees of unsaturation of fatty‐acid oils affect their chemical and morphological domains, which influences their oxidative propensity. The technology of the 1H LF‐NMR energy relaxation time proved to be an effective tool to characterize and monitor PUFA oxidation. [ABSTRACT FROM AUTHOR]

Two-dimensional low-field hydrogen nuclear magnetic resonance (2D 1H LF-NMR) analysis of chemical compounds measures T1 and T2 relaxation times observed as exponential decay curves. Once relaxation curves are measured and stored in the format of discrete digital signals, they must be transformed, mathematically, into spectra that can be read and interpreted. We used primal-dual interior method for convex objectives (PDCO) that provided more accurate reconstructions than the standard algorithms. It is the objective of this paper to estimate the most suitable PDCO parameterization that provide accurate and robust reconstructions of relaxation curves into 2D spectra for LF-NMR under different signal-to-noise ratios. Finding optimal regularization parameters is an active field of mathematical research. PDCO, however, by making use of two regularization parameters instead of a single one, presents a much harder task, where the consolidated search criteria of a single parameter cannot be extended to two parameters. We featured a method based on numerical experiments and simulations that identified optimal and unique model coefficients that maximize PDCO reconstruction accuracy under different signal-to-noise conditions. The coefficients, as determined for artificial signals, increase the confidence of accurate reconstruction for 2D LF-NMR analysis on real lab samples. [ABSTRACT FROM AUTHOR]

Background: To identify and develop the best renewable and low carbon footprint biodiesel substitutes for petroleum diesel, the properties of different biodiesel candidates should be studied and characterized with respect to molecular structures versus biodiesel liquid property relationships. In our previous paper, ¹H low-field nuclear magnetic resonance (LF-NMR) relaxometry was investigated as a tool for studying the liquid-phase molecular packing interactions and morphology of fatty acid methyl esters (FAMEs). The technological potential was demonstrated with oleic acid and methyl oleate standards having similar alkyl chains but different head groups. In the present work, molecular organization versus segmental and translational movements of FAMEs in their pure liquid phase, with different alkyl chain lengths (10-20 carbons) and degrees of unsaturation (0-3 double bonds), were studied with ¹H LF-NMR relaxometry and X-ray, ¹H LF-NMR diffusiometry, and 13C high-field NMR. Results: Based on density values and X-ray measurements, it was proposed that FAMEs possess a liquid crystal-like order above their melting point, consisting of random liquid crystal aggregates with void spaces between them, whose morphological properties depend on chain length and degree of unsaturation. FAMEs were also found to exhibit different degrees of rotational and translational motions, which were rationalized by chain organization within the clusters, and the degree and type of molecular interactions and temperature effects. At equivalent fixed temperature differences from melting point, saturated FAME molecules were found to have similar translational motion regardless of chain length, expressed by viscosity, self-diffusion coefficients, and spin-spin (T2) ¹H LF-NMR. T2 distributions suggest increased alkyl chain rigidity, and reduced temperature response of the peaks' relative contribution with increasing unsaturation is a direct result of the alkyl chain's morphological packing and molecular interactions. Conclusions: Both the peaks' assignments for T2 distributions of FAMEs and the model for their liquid crystal-like morphology in the liquid phase were confirmed. The study of morphological structures within liquids and their response to temperature changes by ¹H LF-NMR has a high value in the field of biodiesel and other research and applied disciplines in numerous physicochemical- and organizational-based properties, processes, and mechanisms of alkyl chains, molecular interactions, and morphologies. [ABSTRACT FROM AUTHOR]

Background: ¹H low field nuclear magnetic resonance (LF-NMR) relaxometry has been suggested as a tool to distinguish between different molecular ensembles in complex systems with differential segmental or whole molecular motion and/or different morphologies. In biodiesel applications the molecular structure versus liquid-phase packing morphologies of fatty acid methyl esters (FAMEs) influences physico-chemical characteristics of the fuel, including flow properties, operability during cold weather, blending, and more. Still, their liquid morphological structures have scarcely been studied. It was therefore the objective of this work to explore the potential of this technology for characterizing the molecular organization of FAMEs in the liquid phase. This was accomplished by using a combination of supporting advanced technologies. Results: We show that pure oleic acid (OA) and methyl oleate (MO) standards exhibited both similarities and differences in the ¹H LF-NMR relaxation times (T2s) and peak areas, for a range of temperatures. Based on X-ray measurements, both molecules were found to possess a liquid crystal-like order, although a larger fluidity was found for MO, because as the temperature is increased, MO molecules separate both longitudinally and transversely from one another. In addition, both molecules exhibited a preferred direction of diffusion based on the apparent hydrodynamic radius. The close molecular packing arrangement and interactions were found to affect the translational and segmental motions of the molecules, as a result of dimerization of the head group in OA as opposed to weaker polar interactions in MO. Conclusions: A comprehensive model for the liquid crystal-like arrangement of FAMEs in the liquid phase is suggested. The differences in translational and segmental motions of the molecules were rationalized by the differences in the ¹H LF-NMR T2 distributions of OA and MO, which was further supported by 13C high field (HF)-NMR spectra and ¹H HF-NMR relaxation. The proposed assignment allows for material characterization based on parameters that contribute to properties in applications such as biodiesel fuels. [ABSTRACT FROM AUTHOR]

ABSTRACT The fouling behavior of polyamide thin-film composite (TFC) membranes modified with amino- and diethylamino-cyclodextrins (CDs) through an in situ interfacial polymerization process is reported. Modified polyamide TFC membranes exhibited improved hydrophilicity, water permeability, and fouling resistance as compared to the unmodified TFC membranes, while restricting the passage of NaCl salt (98.46 ± 0.5%). The increase in hydrophilicity was attributed to the secondary and tertiary hydroxyl groups of the CDs, which were not aminated. The membranes modified with amino-CDs had increased surface roughness while the membranes modified with diethylamino-CDs had smoother surfaces. However, despite the surface roughness of the membranes modified with amino-CDs, low fouling was observed due to the highly hydrophilic surfaces, which superseded the roughness. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40109. [ABSTRACT FROM AUTHOR]

This article describes the preparation and characterization of thin film composite (TFC) membranes for the treatment of water by desalination and removal of organic pollutants. The TFC membranes were prepared using trimesoyl chloride and m-phenyldiamine. Amine-functionalized β-cyclodextrins (CDs) were added to modify membrane flux and rejection. Contact angle measurements demonstrate that the incorporation of the functionalized CDs increased the hydrophilicity of the membrane. All the modified membranes showed improved fluxes with a maximum of 20 L m−2 h−1 compared to 5.59 L m−2 h−1 for the unmodified membranes at a pressure of 100 psi. Further, improved fluxes and salt rejections were achieved (maximum NaCl and Na2SO4 salt rejections were 86% and 94.7%, respectively). Thus, the incorporation of functionalized CDs into TFC membranes improves both the hydrophilicity for minimizing fouling and the rejection of salts without loss of flux. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

Effective targeted drug delivery by cationic liposomes is difficult to achieve because of their rapid clearance from the blood circulation. Bolaamphiphiles that form monolayer membrane may provide vesicles with improved stability, as shown for archaeosomes. We investigated a series of bolaamphiphiles with acetylcholine head groups and systematic structural changes in their hydrophobic domain for their ability to form stable nanovesicles. Bolaamphiphiles with two aliphatic chains separated by a short amide midsection produced spherical nanovesicles ranging in diameter from 80 to 120 nm. These vesicles lost their encapsulated material within 24 hours of incubation in phosphate-buffered saline (PBS). Similar bolaamphiphiles with a longer midsection produced a mixture of fibers and more stable nanovesicles. Bolaamphiphiles with ester amide midsection produced only spherical nanovesicles that were stable during incubation in PBS for several days. Vesicles made from bolaamphiphiles with acetylcholine head groups conjugated to the aliphatic chain via the amine were less stable than vesicles made from bolaamphiphiles with head groups conjugated to the aliphatic chain via the acetyl group. Vesicles that were stable in vitro showed good stability in the blood circulation after intravenous administration to mice. These results help in elucidating the bolaamphiphile structures needed to form stable cationic vesicles for targeted drug delivery. [ABSTRACT FROM AUTHOR]

Home visitation and office reporting are basic to the probation supervision process. They date to the earliest years of statutory probation and are employed both in the preparation of the presentence investigation and in the supervision of offenders. This paper presents a historical overview of the use of home visitation in the beginning years of probation. The purposes and problems of early visitation are contrasted with practices of today. Similarities and contrasts in visitation practices are explored. The changing nature of today's probation, including felony probation, probationer classification systems, and the impact of a drug epidemic, has given rise to a new set of concerns relating to home visitation in urban areas. Unless resolved, these issues may signal an end to routine home visits by probation officers. [ABSTRACT FROM AUTHOR]

The major purpose of the preparticipation physical examination of athletes is to screen for conditions that could predispose the athlete to injury or death. How ever, the examinations offered to many of the athletes in this country fail to adequately accomplish this. This study analyzed the preparticipation health exams of prospective sports participants from all public schools in Richmond County, Georgia for two consecutive years. We sought to identify the components of a preparticipation exam which most accurately identi fied athletes who were at risk of sustaining injury.The most frequently reported problems on the health history were previous injuries, previous hospitaliza tions, and joint problems. These were consistent over the two years. The problems recorded most frequently on the physical exam involved the lower extremities, mouth, teeth, heart, eyes, and genitalia. However, the prevalence of abnormalities found during the first year of the study was significantly lower than that identified in the second year. Analysis of the findings resulted in a more standardized approach to the examination and in an improved examination form. [ABSTRACT FROM PUBLISHER]

Objectives: The purpose of this study was to examine social and psychological factors associated with the use and nonuse of violence among Black adolescents living in a community with a high level of violent crime. Methods. Adolescents (n = 225, 44% male) 11 to 19 years of age living in or around nine housing projects in an urban area were administered an anonymous questionnaire. Results: Self-reported use of violence was associated with exposure to violence and personal victimization, hopelessness, depression, family conflict, previous corporal punishment, purpose in life, self-assessment of the probability of being alive at age 25, and age and was higher among males. Conclusions: These data support the hypothesis that exposure to violence is associated with adolescents' self-reported use of violence. However, adolescents with a higher sense of purpose in life and less depression were better able to withstand the influence of exposure to violence in the home and in the community. [ABSTRACT FROM AUTHOR]

The nutritional characteristics of fatty acid (FA) containing foods are strongly dependent on the FA's chemical/morphological arrangements. Paradoxically the nutritional, health enhancing FA polyunsaturated fatty acids (PUFAs) are highly susceptible to oxidation into harmful toxic side products during food preparation and storage. Current analytical technologies are not effective in the facile characterization of both the morphological and chemical structures of PUFA domains within materials for monitoring the parameters affecting their oxidation and antioxidant efficacy. The present paper is a review of our work on the development and application of a proton low field NMR relaxation sensor (1H LF NMR) and signal to time domain (TD) spectra reconstruction for chemical and morphological characterization of PUFA-rich oils and their oil in water emulsions, for assessing their degree and susceptibility to oxidation and the efficacy of antioxidants. The NMR signals are energy relaxation signals generated by spin–lattice interactions (T1) and spin–spin interactions (T2). These signals are reconstructed into 1D (T1 or T2) and 2D graphics (T1 vs. T2) by an optimal primal-dual interior method using a convex objectives (PDCO) solver. This is a direct measurement on non-modified samples where the individual graph peaks correlate to structural domains within the bulk oil or its emulsions. The emulsions of this review include relatively complex PUFA-rich oleosome-oil bodies based on the aqueous extraction from linseed seeds with and without encapsulation of externally added oils such as fish oil. Potential applications are shown in identifying optimal health enhancing PUFA-rich food formulations with maximal stability against oxidation and the potential for on-line quality control during preparation and storage. [ABSTRACT FROM AUTHOR]

Symptomatic infection with Neisseria gonorrhea (NC) has become a major health problem in the adolescent population. While sexually active adults, who carry Neisseria gonorrhea may serve as a reservoir of infection even when asymptomatic, there are few data documenting the frequency of the asymptomatic carrier state in adolescent males. The purpose of this study was to determine the frequency of NC isolates in a sample of asymptomatic adolescent males (ages 13-18 years). Urethral cultures and gram stains were performed on 249 males (95% black) from a lower socio economic background presenting to an adolescent clinic for routine health care. Of the 249 males cultured, 177 were without symptoms or signs of urethritis. NC were isolated from four (2.26%) patients (Z = 2.03, p ≤ 0.043). They were also isolated from 65 (90.3%) of the remaining 72 who had either symptoms or signs of urethritis. Although 26% of the patients had documented gonococcal disease, only 8% offered a genitourinary complaint at the time of initial evaluation. Our data indicate a low but statistically significant incidence of NC colonization comparable to that found in adult males in this population of asymptomatic adolescent males. [ABSTRACT FROM AUTHOR]

Focuses on the serious complication of burns in children. Changes in skeleton in all major joints following burn injury; Details on the development of subsequent joint ossification; Accounts on the process of heterotopic ossification in burned individuals.

A major stability issue of food and other products containing lipids is their susceptibility to oxidation and the efficacy of endogenous or exogenous antioxidants that are sensitive to internal morphological and chemical structures which are difficult to characterize with current analytical methods. This work develops signal reconstruction of 1H LF‐NMR spin‐lattice (T1) and spin‐spin (T2) energy relaxation times into 2D T2 versus T1 peak graphs of the internal chemical and morphological arrangements within lipid materials, with the potential for efficient structural studies of lipid oxidation and antioxidant efficacy in complex foods. This novel NMR inverse Laplace transformation (ILT) signal processing reconstruction is now applied in a PUFA‐rich linseed oil's thermal autoxidation and antioxidant efficacy study. To characterize antioxidant efficacy, it is important to understand the mechanism of oxidation and the chemical and morphological structural aspects. The initial steps of oxidation show a clear peak shift to shorter T2 versus T1 peak values, for the different poly‐unsaturated fatty acids (PUFA), which for mono‐unsaturated and saturated FAs remain unchanged. These peak shifts are within an oxidation time period needed for hydroperoxides formation. For longer oxidation times a new set of T2 versus T1 peaks are generated with shorter T2 and stable and/or increased T1 values, suggesting formation of aldehydes and polymerized oxidation end products. The chemical changes of the fatty acids of linseed oil are confirmed by their gas chromatography analysis during the studied time interval. Similarly peroxides and aldehydes formation trends are confirmed by PV and p‐ansidine tests, respectively for the same time points. Based on the oxidation study the control of T1 and T2 relaxation times by α tocopherol antioxidant is characterized. In effect α tocopherol antioxidant maintains peak stability during linseed oil's thermal autoxidation, in a 2D T2 versus T1 relaxation time graph of peaks assigned to chemical morphological structures, demonstrating α tocopherol's ability to minimize linseed oil's oxidation. Practical Application: Monitoring of food products oxidation and quality control. 1H LF‐NMR T1 and T2 energy relaxation times reconstructed with PDCO into 2D spectra of material analysis has proven to be an advantageous tool to monitor complex chemical and morphological structural changes during the autoxidation of PUFA‐rich linseed oil. It is suggested that an initial oxidation phase generates a shift, of the original linseed peaks along the T1 = T2 diagonal due to hydroperoxide formation. At longer oxidation times there is an accumulation of peaks below the diagonal line assigned to oligomeric/polymeric termination products, generating a significant "bending effect." α tocopherol addition at effective concentrations is able to change this pattern of PUFA‐rich linseed oil oxidation by blocking early peaks shift and late bending effect. [ABSTRACT FROM AUTHOR]

In the original publication, the acknowledgment section was not published and it is given below now. [ABSTRACT FROM AUTHOR]