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The rotational spectra of two new silicon-bearing carbon chains, H 2 C 3 Si and HSiCCH have been detected by means of Fourier-transform microwave spectroscopy in a supersonic jet source equipped with an electrical discharge. On the basis of measurements between 10 and 42 GHz, precise spectroscopic constants have been determined for both molecules. Along with H29SiCCH and H30SiCCH, which were detected in natural abundance, several other rare isotopic species of HSiCCH were observed using samples enriched in carbon-13 and D. From this isotopic data, a precise semi-experimental equilibrium structure was derived and compared with a re-evaluated semi-experimental equilibrium structure of the parent silylene SiH 2 ; the deuterium isotopic measurements also provide important clues as to the formation pathway of HSiCCH in our discharge. Because other small Si-bearing chains have been detected in the circumstellar envelope of the evolved carbon star IRC+10216, both chains may be of astronomical interest. [Display omitted] • Laboratory detection of two new silicon-bearing carbon chains. • The HSiC angle of HSiCCH is close to that of SiH2. • Isotopic studies point to formation pathway of SiiCCH. [ABSTRACT FROM AUTHOR]

Circadian rhythm disturbances are frequently described in psychiatric disorders such as major depressive disorder, bipolar disorder, and schizophrenia. Growing evidence suggests a biological connection between mental health and circadian rhythmicity, including the circadian influence on brain function and mood and the requirement for circadian entrainment by external factors, which is often impaired in mental illness. Mental (as well as physical) health is also adversely affected by circadian misalignment. The marked interindividual differences in this combined susceptibility, in addition to the phenotypic spectrum in traits related both to circadian rhythms and mental health, suggested the possibility of a shared genetic background and that circadian clock genes may also be candidate genes for psychiatric disorders. This hypothesis was further strengthened by observations in animal models where clock genes had been knocked out or mutated. The introduction of genome-wide association studies (GWAS) enabled hypothesis-free testing. GWAS analysis of chronotype confirmed the prominent role of circadian genes in these phenotypes and their extensive polygenicity. However, in GWAS on psychiatric traits, only one clock gene, ARNTL (BMAL1) was identified as one of the few loci differentiating bipolar disorder from schizophrenia, and macaque monkeys where the ARNTL gene has been knocked out display symptoms similar to schizophrenia. Another lesson from genomic analyses is that chronotype has an important genetic correlation with several psychiatric disorders and that this effect is unidirectional. We conclude that the effect of circadian disturbances on psychiatric disorders probably relates to modulation of rhythm parameters and extend beyond the core clock genes themselves. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Molecular seeds of dust are formed near the central star of carbon-rich stars. • A plethora of unidentified lines are found in the dust formation zone of IRC+10216. • Diatomics and triatomics such as HCN, SiCSi, and SiC2 appear to be likely carriers. • Silicon-bearing molecules play a central role in dust formation. • Additional millimeter-wave laboratory spectroscopy urgently needed. Abstract This article provides an overview of recent astronomical studies and a closely coordinated laboratory program devoted to the study of the physics and chemistry of carbon-rich Asymptotic Giant Branch stars, as illustrated by the archtype star IRC+10216. The increased sensitivity and angular resolution of high altitude, ground-based millimeter-wave interferometers in the past few years has enabled molecular astronomers to determine the excitation and spatial distribution of molecules within a few stellar radii of the central star where the molecular seeds of dust are formed, and thus to critically assess the physicochemical mechanisms of dust formation and growth. However the astronomical studies are crucially dependent on precise laboratory measurements of the rotational spectra — both in the ground and vibrationally excited states of the normal and rare isotopic species as well — of the principal molecules in the inner region which appear to contain only two or three heavy atoms. Much remains to be done by laboratory spectroscopists as evidenced by the large number of unassigned millimeter-wave rotational lines that are observed in the inner envelope of IRC+10216. To assess whether vibrationally excited SiC 2 and HCN are the carriers of some of the unassigned features observed in this source, millimeter-wave laboratory spectra are compared with Cycle 0 observations from the Atacama Large Millimeter-wave Array (ALMA) under experimental conditions that produce both species. Also highlighted are ongoing laboratory studies of the silicon carbides SiC 2 and SiCSi in their ground and excited vibrational states, and c -SiC 3 in its ground vibrational state. Following the initial detection of c -SiC 3 and SiCSi in the outer molecular envelope of IRC+10216, the laboratory spectroscopy was extended to higher frequency in support of the recent interferometric measurements. Thirty-two new millimeter-wave rotational transitions of SiCSi with J ⩽ 48 , K a ⩽ 3 and upper level energies E u ⩽ 484 K in the range from 178 to 391 GHz, and 35 new transitions of c -SiC 3 with J ⩽ 38 , K a ⩽ 20 and E u ⩽ 875 K between 315 and 440 GHz were measured in the laboratory. In addition, five or six rotational transitions in one quanta of each of the three fundamental vibrational modes of SiCSi and the two lowest rotational transitions in the previously unexplored C–C stretching mode ( ν 1 ) of SiC 2 were measured in the normal and doubly substituted 13 C isotopic species. Areas of continued emphasis and the importance of complementary experimental methods and production techniques to detect and assign vibrational transitions are also highlighted. [ABSTRACT FROM AUTHOR]

Non-bleachable (SO 2 -resistant) pigment formation in wine is related to the concentration of grape-derived anthocyanin and tannin, but their relative impact on the formation and composition of SO 2 -resistant pigments is poorly understood. Colour development during fermentation and ageing was analysed in two wines produced from grape batches with different anthocyanin and tannin concentrations. Higher anthocyanin and tannin concentrations extracted during fermentation were associated with increased wine colour density, total SO 2 -resistant pigments and SO 2 -resistant polymeric pigment. During ageing, wine colour density decreased, but differences between the respective wine treatments were retained. Wine tannin concentration was unchanged with age, anthocyanin decreased, and SO 2 -resistant pigments increased. Fractionation of wines indicated that SO 2 -resistant pigments in both polymeric and non-polymeric forms increased with ageing. Increases in tannin pigmentation over time were associated with decreased tannin molecular mass, reflecting the conversion of tannin to lower molecular mass pigmented polymers. The formation of polymeric pigment during ageing was related to the initial wine tannin concentration. However, non-polymeric forms of SO 2 -resistant pigments increased to a greater extent in wines with higher initial anthocyanin and tannin concentrations. The data suggests that both polymeric and low molecular mass anthocyanin derivatives are important for stable wine colour development. [ABSTRACT FROM AUTHOR]

Abstract: Pomegranate fruit was studied by two dimensional NMR correlation spectroscopy during 25 weeks of controlled atmosphere (CA) storage. The proton T 1–T 2 correlation spectrum provided rich information on the characteristics of the environment of water in subcellular compartments. Three relaxation components were identified in the pomegranate arils, which could be assigned to the vacuole, cytoplasm, and cell wall. The results showed that water transferred out of the vacuole to other compartments during storage. Shrinkage of the vacuole was expected as a result of the significant loss of water. The soluble solids content and titratable acidity of the pomegranate decreased during the controlled atmosphere storage, but they were not the major contributor to the change in the relaxation rate of water in the subcellular compartments of the aril tissue. The change in the aril was gradual and not uniform across the tissue in response to CA storage. The variation in the response of the arils to CA diminished at longer storage time. [Copyright &y& Elsevier]

Abstract: MRI and NMR relaxometry were used to monitor the water uptake at macroscopic and microscopic levels during cooking of navy beans. MRI images showed that water gradually penetrated into the center of the bean, and full hydration was achieved after 80 min. A biphasic model, which consists of an exponential phase and a linear phase, was applied to the water uptake data of the navy bean during cooking. The exponential stage finished after 80 min. The NMR relaxometry results indicated there are three water proton components in navy beans. The percentage of bound water decreased gradually as a function of cooking time. The population of the intracellular water reached its maximum at 80 min. A dramatic increase in the population of extracellular water was observed at 150 min. These results suggest that water was incorporated primarily with the intracellular content in navy beans during the initial exponential stage of water uptake. Further water uptake during the linear stage contributed to the increase in the water content in extracellular space. Optical microscopy of the navy bean provided more evidence for the changes in the water distribution at the microscopic level. [Copyright &y& Elsevier]

Examines the effectiveness of feedback in improving the performance of elementary school students. Performance on near-transfer tests after the feedback presentation; Analysis of the forms of task-specific feedback.

Abstract: Real-time PCR is widely employed to quantify PCR products across a range of applications. However, accurate real-time PCR is not always technically feasible, and alternative methods for PCR product quantification can be expensive and time consuming to validate. We have developed an inexpensive, rapid, and immediately accessible protocol to quantify PCR products, by measuring ethidium bromide fluorescence of PCR products excised from agarose gels. This protocol has relevance to a broad range of methods in molecular biology where quantification of PCR products is necessary. [Copyright &y& Elsevier]

The carbon chain molecules vinylcyanoacetylene and cyanovinylacetylene have been investigated between 8 and 41 GHz by Fourier transform microwave spectroscopy of a supersonic molecular beam. Owing to the high spectral resolution of the present technique, significantly more accurate rotational and centrifugal distortion constants have been derived for both molecules. In addition, the dipole moments have been calculated at the B3LYP/cc-pVTZ level of theory. Because these carbon chains are similar in structure and composition to known astronomical molecules and because of their high polarity, both species are good candidates for radioastronomical detection. [Copyright &y& Elsevier]

In striated muscles, the large scaffolding protein obscurin and a small SR-integral membrane protein sAnk1.5 control the retention of longitudinal SR across the sarcomere. How a complex of these proteins facilitates localization of longitudinal SR has yet to be resolved, but we hypothesize that obscurin interacts with a complex of sAnk1.5 proteins. To begin to address this hypothesis, we demonstrate that sAnk1.5 interacts with itself and identify two domains mediating self-association. Specifically, we show by co-precipitation and FLIM-FRET analysis that sAnk1.5 and another small AnkR isoform (sAnk1.6) interact with themselves and each other. We demonstrate that obscurin interacts with a complex of sAnk1.5 proteins and that this complex formation is enhanced by obscurin-binding. Using FLIM-FRET analysis, we show that obscurin interacts with sAnk1.5 alone and with sAnk1.6 in the presence of sAnk1.5. We find that sAnk1.5 self-association is disrupted by mutagenesis of residues Arg64-Arg69, residues previously associated with obscurin-binding. Molecular modeling of two interacting sAnk1.5 monomers facilitated the identification of Gly31-Val36 as an additional site of interaction, which was subsequently corroborated by co-precipitation and FLIM-FRET analysis. In closing, these results support a model in which sAnk1.5 forms large oligomers that interact with obscurin to facilitate the retention of longitudinal SR throughout skeletal and cardiac myocytes. • Small Ank1 isoforms 1.5, 1.6, and 1.9 interact with themselves and each other. • Amino acids Gly31-Val36 and Arg64-Arg69 regulate small Ank1 self-association. • Obscurin interacts with a complex of sAnk1.5 proteins. • Obscurin-binding enhances sAnk1.5 protein complex formation. • sAnk1.5 mediates obscurin interaction with sAnk1.6 in cells. [ABSTRACT FROM AUTHOR]

• A novel high pressure NMR probe design that interfaces with unilateral magnets. • Commercial pressure reactor modified to create a NMR probe. • Inexpensive high pressure probe design and construction. • Pressure dependent relaxometry correlation. A low cost, portable, high volume, stainless steel pressure reactor is modified to easily perform magnetic resonance relaxometry at industrially relevant pressures. Unlike existing pressurization strategies common to nuclear magnetic resonance (NMR) spectroscopy, this approach is amenable to realistic samples that feature heterogeneity and have traditionally escaped NMR study at pressure. This pressure reactor/NMR probe combination is easily accommodated by most single-sided and other low magnetic field permanent magnet assemblies. The performance of the probe is demonstrated by accomplishing NMR relaxometry on polydimethylsiloxane at different pressures with two types of unilateral magnets. [ABSTRACT FROM AUTHOR]

The occurrence and rate of wildlife-vehicle collisions are related to both anthropocentric and environmental variables, however, few studies compare collision risks for multiple species within a model framework that is adaptable and transferable. Our research compares collision risk for multiple species across a large geographic area using a conceptually simple risk framework. We used six species of native terrestrial mammal often involved with wildlife-vehicle collisions in south-east Australia. We related collisions reported to a wildlife organisation to the co-occurrence of each species and a threatening process (presence and movement of road vehicles). For each species, we constructed statistical models from wildlife atlas data to predict occurrence across geographic space. Traffic volume and speed on road segments (also modelled) characterised the magnitude of threatening processes. The species occurrence models made plausible spatial predictions. Each model reduced the unexplained variation in patterns and distributions of species between 29.5% (black wallaby) and 34.3% (koala). The collision models reduced the unexplained variation in collision event data between 7.4% (koala) and 19.4% (common ringtail possum) with predictor variables correlating similarly with collision risk across species. Road authorities and environmental managers need simple and flexible tools to inform projects. Our model framework is useful for directing mitigation efforts (e.g. on road effects or species presence), predicting risk across differing spatial and temporal scales and target species, inferring patterns of threat, and identifying areas warranting additional data collection, analysis, and study. [ABSTRACT FROM AUTHOR]

Abstract: Exploring the effects of cations in whey protein-based gels (WPG) is of importance when these gels are used for controlled release applications in food systems. The objective of this study was to evaluate both water uptake and cation release from heat-set WPGs. Magnetic Resonance Imaging and NMR relaxometry were employed to study the uptake and release. A non-paramagnetic (Ca+2) and a paramagnetic cation (Mn+2) were incorporated into the WPG as model divalent cations. Cylindrical pieces of WPGs with manganese were immersed in water (pH 2.40, 7.00, 10.40) or in EDTA solution whereas WPGs with calcium were immersed in water at pH 2.40. Water uptake by the gels was influenced by both ionic environment and pH. The release of Mn+2 from WPG was enhanced by the presence of EDTA. Relaxation spectra of Mn+2-loaded gels were significantly influenced by pH of the suspending fluid and by the presence of EDTA. Results of relaxometry experiments, obtained with Ca+2-loaded gels immersed in water at pH 2.40, indicated a strong correlation (R 2 > 0.99) between relative areas of the proton pools and the amount of calcium released to the medium. Results support the use of MRI and NMR to monitor cation release and water uptake in WPG, non-destructively. [Copyright &y& Elsevier]

Recent advances in circumstellar metal chemistry and laser-coolable molecules have spurred interest in the spectroscopy and electronic properties of alkaline earth metal-bearing polyatomic molecules. We report the microwave rotational spectra of two members of this important chemical family, the linear magnesium-carbon chains MgC 4 H and MgC 3 N, detected with cavity Fourier transform microwave spectroscopy of a laser ablation-electric discharge expansion. The rotation, fine, and hyperfine parameters have been derived from the precise laboratory rest frequencies. These experimental results, combined with a theoretical quantum chemical analysis, confirm the recent identification of MgC 4 H and MgC 3 N in the circumstellar envelope of the evolved carbon-rich star IRC+10216. The spectroscopic data also provide insight into the structural and electronic properties that influence the metal-based optical cycling center in this unique class of laser-coolable polyatomics. [Display omitted] • MgC 4 H and MgC 3 N were detected in the laboratory with microwave spectroscopy. • Confirmation of the astronomical identification in carbon-rich circumstellar envelopes. • Fine and hyperfine structure reveals a highly metal-localized unpaired electron. [ABSTRACT FROM AUTHOR]

Abstract: Transitions between the spin–rotational levels of the 12CH radical in the v =1 level of the X 2Π state have been studied by the technique of laser magnetic resonance at far-infrared wavelengths. The data have been combined with a measurement of lambda-doubling transition frequencies at 7GHz to determine an improved set of molecular parameters for CH in the v =1 level. The parameters provide information on the effects of vibrational excitation on the structural properties of CH. Accurate predictions of the transition frequencies between the low-lying levels of the radical in the absence of a magnetic field have also been made. Small inconsistencies in the least-squares fit of the laser magnetic resonance data prompted re-measurement of three far-infrared laser frequencies, the 122.5μm line of CH2F2 pumped by 9R(22), the 122.5μm line of CH2F2 pumped by 9P(8) and the 554.4μm line of CH2CF2 pumped by 10P(14). The new measurements differ by as much as 3.8MHz from those made previously and are more accurate; they also remove the inconsistencies in the fit. The re-measured frequencies of the two 122.5μm lines are identical within experimental error which suggests that the far-infrared lasing transition is the same, namely the rR23(32) transition in the v 9=1 level of CH2F2. [Copyright &y& Elsevier]

[Display omitted] • New high-speed method for fitting and predicting rotational spectra. • Factors of hundreds faster than existing methods. • Flexible, lightweight, and parallelizable code. The advent of chirped-pulse Fourier transform microwave spectroscopy has dramatically increased the acquisition rate of high-resolution data. However, this data is only useful when it can be translated into molecule-specific information, and ultimately chemical knowledge. To adapt to this high data rate regime, new data analysis tools, which do not result in commensurate increases in time, are needed. Several methods, both computational and experimental, have been developed to simplify and automate the assignment of microwave spectra, and such tools can also make microwave spectroscopy far more approachable and usable for non-experts. Computationally efficient spectral assignment is a particularly promising avenue to enable rapid and nearly exhaustive spectral identification. Towards this end, we have recently developed an efficient, high-speed program for the prediction and fitting of rotational spectra. This program is built on a simple framework that is applicable to a wide variety of molecules. We present this program, discuss its performance, and demonstrate its use in fitting broadband spectra at centimeter wavelengths. [ABSTRACT FROM AUTHOR]

Semi-experimental equilibrium and high-level quantum-chemical structures are reported for three hydrocarbons containing the vinyl (H 2 C = CH–) group: vinyl acetylene, vinyl diacetylene and vinyl cyanide. Semi-experimental equilibrium structures have been obtained through a combination of new experimental results from Fourier transform microwave spectroscopy combined with force field calculations performed at the coupled-cluster singles and doubles model augmented by a perturbative correction for triple excitations, CCSD(T), level of theory. Comparison against equilibrium structures obtained by high-level CCSD(T) computations employing large correlation-consistent basis sets with up to 1090 basis functions yields excellent agreement. From this combined study, we find the carbon atom backbone in the vinyl group is largely unaffected when bound to different substituents, such as –H, –CCH, –C 4 H, –CN. [ABSTRACT FROM AUTHOR]

[Display omitted] • Rotational spectrum (130–360 GHz) measured for chlorobenzene. • Constants determined for ground vibrational states of [35Cl]-, [37Cl]-chlorobenzene. • Constants determined for 7 fundamental states, 8 overtone/combination states of [35Cl]-chlorobenzene. • Constants determined for 4 fundamental states of [37Cl]-chlorobenzene. • Data enable detailed comparisons of spectroscopic constants with structurally related compounds. The rotational spectra of [35Cl]- and [37Cl]-chlorobenzene (C 6 H 5 Cl) have been studied from 2 to 18 GHz and 130–360 GHz, resulting in the measurement, assignment, and least-squares fitting of almost 40,000 transitions of twenty-one vibrational states. Previously measured [35Cl]- and [37Cl]-chlorobenzene ground-state transitions were combined with newly measured transitions and fit to A-reduced, partial sextic Hamiltonian models with low-error (σ total fit <0.05 MHz). Analysis of the 2–18 GHz spectrum allowed for refinement of the nuclear hyperfine coupling constants for the ground-state spectra of both isotopologues, while measurement of the 130–360 GHz spectrum provided sufficient information to determine the sextic centrifugal distortion constants of the ground states for the first time. From these millimeter-wave data collected at room temperature, the spectroscopic constants for the lowest-energy fundamentals of [35Cl]-chlorobenzene (ν 20 , ν 30 , ν 11 , ν 14 , ν 19 , ν 29 and ν 18) and [37Cl]-chlorobenzene (ν 20 , ν 30 , ν 11) were determined. As with previous studies of chloroarenes, the computed (B3LYP/6–311+G(2d,p)) spectroscopic constants show quite close agreement with the experimentally determined values. [ABSTRACT FROM AUTHOR]

Increasing the colonization rate of metapopulations can improve persistence, but can also increase exposure to threats. To make good decisions, managers must understand whether increased colonization is beneficial or detrimental to metapopulation persistence. While a number of studies have examined interactions between metapopulations, colonization, and threats, they have assumed that threat dynamics respond linearly to changes in colonization. Here, we determined when to increase colonization while explicitly accounting for non-linear dependencies between a metapopulation and its threats. We developed patch occupancy metapopulation models for species susceptible to abiotic, generalist, and specialist threats and modeled the total derivative of the equilibrium proportion of patches occupied by each metapopulation with respect to the colonization rate. By using the total derivative, we developed a rule for determining when to increase metapopulation colonization. This rule was applied to a simulated metapopulation where the dynamics of each threat responded to increased colonization following a power function. Before modifying colonization, we show that managers must understand: (1) whether a metapopulation is susceptible to a threat; (2) the type of threat acting on a metapopulation; (3) which component of threat dynamics might depend on colonization, and; (4) the likely response of a threat-dependent variable to changes in colonization. The sensitivity of management decisions to these interactions increases uncertainty in conservation planning decisions. [ABSTRACT FROM AUTHOR]

Infrared action spectra of the protonated forms of two fundamental organic nitriles, vinyl cyanide, C2H3CN , and ethyl cyanide, C2H5CN , have been observed using the FELion 22-pole ion trap apparatus and the Free Electron Laser for Infrared eXperiments (FELIX) at Radboud University, Nijmegen (The Netherlands). Vibrational bands of both ions were observed in the wavenumber regime between 300 and 2500 cm−1 and spectroscopically assigned based on results from anharmonic force field calculations performed here at the coupled cluster level of theory. As the action spectroscopy scheme used in the present study probes the Ne-tagged weakly bound complexes, C 2 H 3 CNH + − Ne and C 2 H 5 CNH + − Ne, corresponding quantum-chemical calculations of these systems were also performed. Significant blueshifts observed for the strong -CNH + bending modes indicate that the neon atom is attached to the proton bound to the nitrile group in both molecular ions. [Display omitted] • First infrared spectroscopic study of protonated vinyl- and ethyl cyanide. • Free Electron Laser for Infrared eXperiments, FELIX, used as radiation source. • Detection via infrared photodissociation of the Ne-ion clusters. • Experimental study complemented by high-level CCSD(T) calculations. [ABSTRACT FROM AUTHOR]

[Display omitted] • Rotational transitions from 8 to 38 and 130 to 360 GHz used to study anti- and gauche- 4-cyano-1-butyne (an isomer of pyridine). • Spectroscopic constants for the ground vibrational states determined for the first time. • Hyperfine resolved transitions included to determine quadrupole coupling constants (χ aa , χ bb , and χ cc). • Experimental energy difference determined between the conformers (Δ E anti – gauche). The analysis of the rotational spectrum of 4-cyano-1-butyne, an open-chain isomer of pyridine, is presented herein for the first time. Transitions for the ground vibrational states of both conformational isomers, anti and gauche , were observed in the 8–38 GHz and 130–360 GHz frequency ranges and fit to effective sextic distorted-rotor Hamiltonians with low uncertainty (σ fit < 50 kHz), allowing for their potential detection by radioastronomy or in harsh reaction environments. The microwave region includes hyperfine-split transitions for both conformers, allowing for the experimental determination of the χ aa , χ bb , and χ cc quadrupole coupling constants. In the millimeter-wave region, not every observable ground-state transition could be satisfactorily addressed by a single-state Hamiltonian due to Coriolis coupling with the low-energy vibrationally excited states. Thus, effective single-state fits of the ground states were obtained by including only K a -series transitions without obviously perturbed energy levels. Importantly, the effective fit does include the most intense transitions throughout the observed frequency ranges. The predicted values (MP2/cc-pVTZ) are in close agreement with the experimental spectroscopic constants. These data provide a sufficient foundation for the identification of anti- and gauche- 4-cyano-1-butyne in the interstellar medium by radioastronomy. The gauche conformer is estimated to lie 1.00 (5) kcal/mol higher in energy than the anti conformer, as determined using experimental transition intensities. [ABSTRACT FROM AUTHOR]

Abstract: Characterizing water and fat distributions in fried foods is of major importance in terms of taste and nutrition. The objective of this study was to introduce a new technique to quantify water and fat distributions of chicken nuggets coated with methylcellulose (MC) through the use of magnetic resonance imaging (MRI) and NMR relaxometry. Multi-slice-multi-echo (MSME-Spin Echo based) images were performed on a 1.03 T spectrometer for the whole chicken nuggets to obtain relaxation time distribution of different regions (core and crust) of the nugget. MSME images provided the relaxation spectra of the core and crust separately and showed that relaxation times and relative areas of the proton pools in crust and core regions are correlated (mostly, R 2 > 0.85) with moisture and fat content. Results demonstrated that MSME images in combination with T 2 relaxometry are appropriate tools to quantify spatial water and fat distribution in various food products. [Copyright &y& Elsevier]

Abstract: The objective of this study was to investigate the influence of boiling, roasting and frying on the digestion of peanuts in simulated gastric environment. Raw and processed peanuts were tested for disintegration in a model stomach system. The differences in disintegration rate were explained with respect to the changes in moisture absorption and texture. The absorption of moisture and the swelling of peanuts during gastric digestion were studied using Magnetic Resonance Imaging (MRI). The results show that processing improved the gastric disintegration of peanuts, and the disintegration rate was in an order of fried > roasted > boiled > raw peanuts. The changes in total weight, moisture and the dry solid loss in the samples were described by Linear–exponential equation, Peleg''s equation and the Weibull equation, respectively. Absorption of gastric juice played a critical role in softening the texture contributing to the breakdown of peanuts. Static soaking test indicated that the disintegration rate, as indicated by half time, has a good exponential relationship with the textural parameters of soaked samples. MRI shows potential as being used to analyze the mass transfer phenomenon in solid foods under digestion. [Copyright &y& Elsevier]

Abstract: We present the development of an Overhauser dynamic nuclear polarization (DNP) instrument at 0.04T using 1.1GHz (L-band) electron spin resonance frequencies (ESR) and 1.7MHz 1H nuclear magnetic resonance frequencies. Using this home-built DNP system, the electron–nucleus coupling factor of 4-oxo-TEMPO dissolved in water was determined as 0.39±0.06 at 0.04T. The higher coupling factor obtained at this field compared to higher magnetic fields, such as 0.35T, directly translates to higher enhancement of the NMR signal and opens up a wider time scale window for observing water dynamics interacting with macromolecular systems, including proteins, polymers or lipid vesicles. The higher enhancements obtained will facilitate the observation of water dynamics at correlation times up to 10ns, that corresponds to more than one order of magnitude slower dynamics than accessible at 0.35T using X-band ESR frequencies. [Copyright &y& Elsevier]

[Display omitted] • Phenylpropiolonitrile (C 6 H 5 C 3 N) has been characterized in the gas phase. • Its medium resolution far- and mid-infrared spectrum has been measured for the first time. • Rotational transitions have been recorded in the centimeter- and millimeter-wave range. • Quantum chemistry was used to guide spectroscopic assignments and parameter determina-tion. • We conclude phenylpropiolonitrile is a strong candidate for interstellar detection. The evidence for benzonitrile (C 6 H 5 CN) in the starless cloud core TMC–1 makes high-resolution studies of other aromatic nitriles and their ring-chain derivatives especially timely. One such species is phenylpropiolonitrile (3-phenyl-2-propynenitrile, C 6 H 5 C 3 N), whose spectroscopic characterization is reported here for the first time. The low resolution (0.5 cm−1) vibrational spectrum of C 6 H 5 C 3 N has been recorded at far- and mid-infrared wavelengths (50–3500 cm−1) using a Fourier Transform interferometer, allowing for the assignment of band centers of 14 fundamental vibrational bands. The pure rotational spectrum of the species has been investigated using a chirped-pulse Fourier transform microwave (FTMW) spectrometer (6– 18 GHz), a cavity enhanced FTMW instrument (6–20 GHz), and a millimeter-wave one (75–100 GHz, 141–214 GHz). Through the assignment of more than 6200 lines, accurate ground state spectroscopic constants (rotational, centrifugal distortion up to octics, and nuclear quadrupole hyperfine constants) have been derived from our measurements, with a plausible prediction of the weaker lines through calculations. Interstellar searches for this highly polar species can now be undertaken with confidence since the astronomically most interesting radio lines have either been measured or can be calculated to very high accuracy below 300 GHz. [ABSTRACT FROM AUTHOR]

• First high-resolution infrared study of ethyl cyanid. • Four energetically lowest vibrational fundamentals studied. • Global fits of infrared and pure rotational spectra performed. • Strong vibrational satellites towards high mass star forming region assigned. The high resolution vibrational spectrum of ethyl cyanide (C 2 H 5 CN) has been investigated in the far-IR using synchrotron-based Fourier transform spectroscopy. The assignment was performed using the Automated Spectral Assignment Procedure (ASAP) allowing accurate rotational energy levels of the four lowest fundamental vibrations of the species, namely the v 13 = 1 @ 205.934099(8) cm−1, v 21 = 1 @ 212.141101(8) cm−1, v 20 = 1 @ 372.635293(15) cm−1, and v 12 = 1 @ 532.699617(16) cm−1 states, to be determined. The analysis not only confirms the applicability of the ASAP in the treatment of (dense) high-resolution infrared spectra but also reveals some of its limitations. Complementary to the infrared study, the pure rotational spectrum of C 2 H 5 CN was also studied in selected frequency ranges from 75 to 255 GHz. New observations of a prototypical high-mass star-forming region, G327.3–0.6, performed with the Atacama Large Millimeter Array show that vibrational satellites of C 2 H 5 CN can be very intense, of order several tens of Kelvin in units of brightness temperature. [ABSTRACT FROM AUTHOR]