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BACKGROUND: Rice grain analogues with slow starch digestibility are commonly associated with an unsatisfactory texture, often leading to consumer dissatisfaction. Alginate encapsulation has been applied to reduce the digestibility of corn and potato starch. The fine molecular structures of rice starch can greatly determine its digestibility and texture. However, it remains unclear whether a combination of alginate encapsulation and varied starch molecular structures can be employed to create rice grain analogues that offer both slow starch digestibility and an appealing texture. RESULTS: For the first time, the present study constructed alginate‐encapsulated rice beads (as a rice grain analogue). A wide range of starch digestion rates were found among alginate‐encapsulated rice beads prepared with different rice varieties, and only certain rice varieties (e.g. Subei and Nanjing) were able to result in rice beads with slower starch digestibility than their parental rice kernels. More importantly, all rice beads showed a relatively softer texture compared to their parental rice kernels. Correlation analysis showed that starch digestion rate, hardness and stickiness were all positively correlated with the ratio of short‐range amorphous regions in rice bead samples, as obtained from Fourier transform‐infrared spectroscopy, but not with the relative crystallinity. CONCLUSION: Collectively, these results suggest that rice beads with slower starch digestion rate and softer texture could be obtained by choosing rice varieties that develop more short‐range ordered structure after cooking. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

An accurate characterization of the fine molecular structure of starch in terms of the chain length distribution (CLD) of amylopectin requires complete dispersion of the starch in a solvent, either buffer or water and the non-interference of this on the subsequent enzymatic debranching of starch with isoamylase (pretreatments before determining the CLD). In this study, the HYLON V and HYLON VII starches (commercial high-amylose corn starches) were selected, since high-amylose starches typically present difficulties in their dispersion and, therefore, the study of their fine structure can commonly present errors. The goal of this research was to study two water dispersion treatments (1. boiling water for 1 h and 2. autoclaving at 120 °C and 15 Psi for 15 min) to achieve a fast and reliable method of the fine structure of two high-amylose corn starches using high-performance size exclusion chromatography coupled with a refractive index detector (HPSEC-RID) and high-performance anion-exchange chromatography coupled a pulsed amperometric detector (HPAEC-PAD). The HPSEC-RID chromatograms of both starches showed better resolution using autoclaving than boiling water treatment. The two starches tested had higher amylose and degree of polymerization (DP) values utilizing the autoclaving than the boiling water treatment. However, no appreciable differences were observed in the CLD values employing HPAEC-PAD for either of the two water dispersion treatments. Lastly, the water dispersion treatment by autoclaving before enzymatic debranching is recommended to obtain a more accurate quantification of the amylose content of high-amylose starches. [ABSTRACT FROM AUTHOR]

[Display omitted] Liquid-liquid phase separation is a key phenomenon in the formation of membrane-less structures within the cell, appearing as liquid biomolecular condensates. Protein condensates are the most studied for their biological relevance, and their tendency to evolve, resulting in the formation of aggregates with a high level of order called amyloid. In this study, it is demonstrated that Human Insulin forms micrometric, round amyloid-like structures at room temperature within sub-microliter scale aqueous compartments. These distinctive particles feature a solid core enveloped by a fluid-like corona and form at the interface between the aqueous compartment and the glass coverslip upon which they are cast. Quantitative fluorescence microscopy is used to study in real-time the formation of amyloid-like superstructures. Their formation results driven by liquid–liquid phase separation process that arises from spatially heterogeneous distribution of nuclei at the glass-water interface. The proposed experimental setup allows modifying the surface-to-volume ratio of the aqueous compartments, which affects the aggregation rate and particle size, while also inducing fine alterations in the molecular structures of the final assemblies. These findings enhance the understanding of the factors governing amyloid structure formation, shedding light on the catalytic role of surfaces in this process. [ABSTRACT FROM AUTHOR]

Density Functional Theory (DFT) suffers from a strong dichotomy between accuracy and consistency. There exists a paucity of a generic linear route to the systematic improvement of computed results. Benchmark studies are often unidimensional and based on molecular/atomic properties that contour on a single Potential Energy Surface. Thus, the DFT functionals so developed and optimized to similar chemical accuracy lack a universal adherence to the unique density distribution for a fixed nuclear arrangement. We have identified this as a major source of inconsistency within the DFT framework and have explored through the cross-correlations between Structure, Energy, and Dipolar Strength. Since Range Separated Hybrid (RSH) functionals are well-known in literature to produce one of the finest molecular structures in both ground and excited states, in this communication, we have utilized CAM-B3LYP, LC- ω HPBE, and ω -B97XD to explore the above cross-correlations on well-studied test subjects comprising of Anthracene, Tetracene, Phenanthrene and Pyrene in all possible combination of these functionals. The combined responses from the functionals have revealed that major inconsistency operating between structure and energy dictates the variations in the dipolar strength and that lower RMSD and higher charge reorganization are the keys to higher dipolar strength. While LC- ω HPBE stands out, CAM-B3LYP and ω B97XD remain comparatively more like each other except in the Adiabatic Energy Difference (AED) trend. [ABSTRACT FROM AUTHOR]

Arylalkane-derived prodrugs of arylacetic acids are a small group of substances that have long been known for their anti-inflammatory action. Despite their ease of synthesis and good potential for the development of new potent and safe anti-inflammatory agents, this group of substances has not received much attention from researchers so far. Therefore, representative arylalkane derivatives were investigated through molecular docking techniques to verify the possible hepatic activation mode toward active metabolites by CYP1A2. In this regard, arylalkanoic acid prodrugs were docked with a crystallographic structure of human CYP1A2, in which the enzyme is co-crystallized with the selective competitive inhibitor α-naphthoflavone BHF. Of note, all the examined compounds proved capable of interacting with the enzyme active site in a manner similar to Nabumetone, thus confirming that a productive metabolic transformation is feasible. On the basis of these findings, it is possible to argue that subtle differences in the way CYP1A2 accommodates the ligands depend on the fine details of their molecular structures. Overall, these data suggest that compounds simply formed by an aromatic moiety bearing an appropriate alkane-derived chain could lead to innovative anti-inflammatory agents. [ABSTRACT FROM AUTHOR]

Simple Summary: We connect the Planck scale to the subatomic world without assuming a priori that such a connection exists; we deduce the physical meaning of the famous dimensionless fine-structure constant 1/137 (known simply as 137); we relate the masses of quarks, leptons, and vector bosons to the Higgs mass, i.e., we derive scaling relations for the entire mass ladder of the subatomic world; we deduce from first principles the origin and physical significance of Koide's K = 2 / 3 enigmatic constant and analogous quark and vector boson constants; and we calculate the gauge coupling factors of quarks, leptons, bosons, and the weak interaction in terms of only the Higgs field and Koide's constant. Natural systems of units { U i } need to be overhauled to include the dimensionless coupling constants { α U i } of the natural forces. Otherwise, they cannot quantify all the forces of nature in a unified manner. Thus, each force must furnish a system of units with at least one dimensional and one dimensionless constant. We revisit three natural systems of units (atomic, cosmological, and Planck). The Planck system is easier to rectify, and we do so in this work. The atomic system discounts { G , α G } , thus it cannot account for gravitation. The cosmological system discounts { h , α h } , thus it cannot account for quantum physics. Here, the symbols have their usual meanings; in particular, α G is the gravitational coupling constant and α h is Dirac's fine-structure constant. The speed of light c and the impedance of free space Z 0 are resistive properties imposed by the vacuum itself; thus, they must be present in all systems of units. The upgraded Planck system with fundamental units UPS : = { c , Z 0 , G , α G , h , α h , ... } describes all physical scales in the universe—it is nature's system of units. As such, it reveals a number of properties, most of which have been encountered previously in seemingly disjoint parts of physics and some of which have been designated as mere coincidences. Based on the UPS results, which relate (sub)atomic scales to the Planck scale and the fine-structure constant to the Higgs field, we can state with confidence that no observed or measured physical properties are coincidental in this universe. Furthermore, we derive from first principles Koide's K = 2 / 3 enigmatic constant and additional analogous quark and vector boson constants. These are formal mathematical proofs that justify a posteriori the use of geometric means in deriving the quark/boson mass ladder. This ladder allows us to also calculate the Higgs couplings to the vector bosons and the Weinberg angle in terms of K only, and many of the "free" parameters of the Standard Model of particle physics were previously expected to be determined only from experiments. [ABSTRACT FROM AUTHOR]

Tritrichomonas muris is a common flagellated protist isolated from the cecum of wild rodents. This commensal protist has been shown previously to alter immune phenotypes in laboratory mice. Other trichomonads, referred to as Tritrichomonas musculis and Tritrichomonas rainier, also naturally colonize laboratory mice and cause immune alterations. This report formally describes two new trichomonads, Tritrichomonas musculus n. sp., and Tritrichomonas casperi n. sp., at the ultrastructural and molecular level. These two protists were isolated from laboratory mice and were differentiated by their size and the structure of their undulating membrane and posterior flagellum. Analysis at the 18S rRNA and trans‐ITS genetic loci supported their designation as distinct species, related to T. muris. To assess the true extent of parabasalid diversity infecting laboratory mice, 135 mice bred at the National Institutes of Health (NIH) were screened using pan‐parabasalid primers that amplify the trans‐ITS region. Forty‐four percent of mice were positive for parabasalids, encompassing a total of eight distinct sequence types. Tritrichomonas casperi and Trichomitus‐like protists were dominant. T. musculus and T. rainier were also detected, but T. muris was not. Our work establishes a previously underappreciated diversity of commensal trichomonad flagellates that naturally colonize the enteric cavity of laboratory mice. [ABSTRACT FROM AUTHOR]

Anomalous long‐distance propagation of Very High Frequency radio waves of aeronautical navigation systems was investigated by an airborne Instrument Landing System (ILS) localizer (ILS LOC) receiver installed on the ground at Kure, Japan (34.245°N, 132.528°E). Intense ILS LOC type signals were observed and the received power was strong enough for the aviation receiver to output course deviation. The radio source was identified by receiving the Morse Code for identification as the localizer‐type directional aid (LDA) serving the Runway‐21 of the Hualien Airport, Taiwan (24.0396°N, 121.6221°E) of which beam pointed close to the receiver. This result supports that the source of the signals often observed at the same frequency at the same location is most probably the LDA at the Hualien Airport. The maximum received power was −99 dBm for an omni‐directional antenna. It was strong enough to cause co‐channel interference. Considering stronger power (−70 dBm) found in previous observations at the same frequency at the same location, anomalous propagation of ILS LOC signals by the Es layer could be a cause of interference when a receiver was near the center of the ILS LOC beam. The course deviation output was consistent with the geometry between the beam of Runway‐21 LDA at the Hualien Airport and the receiver. However, the observed course deviation fluctuated remarkably even when the received power was strong enough. The fluctuation of the course deviation may indicate the structure of the Es layer, and observation of the course deviation could be used to diagnose the Es layer structure. Plain Language Summary: Intense signals of an instrument landing system localizer (ILS LOC) for aircraft navigation was detected over anomalously long distance (about 1,550 km). The ILS LOC equivalent signal from Hualien Airport, Taiwan was observed by an ILS LOC receiver for aviation on the ground at Kure, Japan. The signal was strong enough to provide deviation of the position from the center of the beam and was strong enough to cause co‐channel interference. Considering stronger power found in previous observations at the same frequency at the same location, anomalous propagation of ILS LOC signals by the sporadic E (Es) layer, which is an ionospheric layer with a high electron density and thin altitudinal thickness, could be a cause of interference when a receiver was near the center of the ILS LOC beam. The fluctuation of the course deviation may indicate the structure of the Es layer, and could be used to diagnose the Es layer structure. Key Points: Anomalous long‐distance propagation of Very High Frequency radio air navigation signals by the sporadic E layer was detected by an aviation receiverThe received signal was strong enough to cause interference to an aviation receiver at distances far outside the intended service areaVariation of course deviation information obtained from the ILS‐LOC signal could be used to study fine structures of the Es layer [ABSTRACT FROM AUTHOR]

The effective Hamiltonians of the fine structure of Fe2+ (5D) terms are derived using the methods of operator perturbation theory taking into account covalent bonds between iron and oxygen ions. The energy operators of coupling of magnetic and electric dipole moments with the electric field are obtained for states of multiplets Fe2+ (5E) and Fe2+ (5T2) with minimal sets of parameters. The energy spectra of low-lying states, the magnetic anisotropy parameters, and the distribution of quadrupole and induced electric dipole moments over all positions in the unit cell are calculated. The results of calculations are compared with available experimental data. [ABSTRACT FROM AUTHOR]

The effective Hamiltonians of the fine structure of Fe2+ (5D) terms are derived using the methods of operator perturbation theory taking into account covalent bonds between iron and oxygen ions. The energy operators of coupling of magnetic and electric dipole moments with the electric field are obtained for states of multiplets Fe2+ (5E) and Fe2+ (5T2) with minimal sets of parameters. The energy spectra of low-lying states, the magnetic anisotropy parameters, and the distribution of quadrupole and induced electric dipole moments over all positions in the unit cell are calculated. The results of calculations are compared with available experimental data. [ABSTRACT FROM AUTHOR]

The thermal properties of dough are critical for eating and processing quality of wheat flour‐based products. Although the gelatinization properties of wheat starch or flour as affected by starch molecular structures have been investigated, it remains largely unexplored how starch structures determine the gelatinization properties of wheat dough. The gelatinization properties of 10 wheat flours and corresponding doughs with distinct starch fine molecular structures are thus investigated. A parabolic relationship is observed between amylose content and gelatinization temperatures of both wheat flour and dough. Amylopectin molecular size is positively correlated while amylose molecular size negatively correlates with gelatinization onset and peak temperatures of wheat flour. Amylose molecular size is negatively correlated with gelatinization temperatures of wheat dough. Possible mechanisms are further discussed. These results provided first associations between starch molecular structures and thermal properties of wheat dough, and their difference compared to those from wheat flour, which can help the food industry select suitable wheat varieties with improved dough quality. [ABSTRACT FROM AUTHOR]

A method for measuring cross sections at colliders for the case where the center-of-mass frame of colliding particles moves in the laboratory frame is proposed. Within this method, the energy dependence of the cross section is extracted from the angular distribution of interaction products. The method applied to the process is found to be sensitive. This method provides the possibility of studying the fine structure of the cross section near the threshold at scales much less than the energy spread of the beams used. Similar measurements may be implemented in experiments at the Super Charm-Tau Factory. [ABSTRACT FROM AUTHOR]

Zero-phonon components of the 3T1(3H) → 5E(5D) transition between inner shells of the Fe2+ ion have been detected in low-temperature photoluminescence spectra of Fe-doped ZnSe crystals. Six spectral components corresponding to dipole-allowed transitions between the components 3T1(3H) and 5E(5D) of the fine structure, which is caused by the spin–orbit coupling, have been reliably detected at temperatures of 5–10 K. The electronic spectrum of the Fe2+ ion in the ZnSe matrix has been refined using the data obtained. [ABSTRACT FROM AUTHOR]

We use spectro-polarimetric data recorded by Hinode to analyze the mag-netic field configuration of a part of a sunspot (AR 10923) where a bundle of penumbral filaments are intruding into its umbra. We want to explore the role of the sunspot magnetic configuration in the formation and kinematics of the fine-structures, such as umbral dots and light bridges, inside the sunspot umbra. Both direct inferences from polarization Stokes profiles and the inversion results using the SIR code indicate an aligned magnetic field configuration in the umbra where moving umbral dots are easily formed at the leading edges of the rapidly intruding penumbral filaments. We suggest that the magnetic field topology is rearranged leading to the observed aligned magnetic field lines via magnetic reconnection process by which a part of the magnetic energy is converted into thermal and kinetic energy. This new configuration causes the umbral fine-structures to form easily and more frequently. [ABSTRACT FROM AUTHOR]

As a demonstration of the analysis of the electronic structure and the nuclear dynamics from time-resolved near-edge X-ray absorption fine structure (TR-NEXAFS), we present the TR-NEXAFS spectra of pyrazine following the excitation to the 1B2u(ππ*) state. The spectra are calculated combining the frozen-core/core-valence separated equation-of-motion coupled cluster singles and doubles approach for the spectral signatures and the multiconfiguration time-dependent Hartree method for the wave packet propagation. The population decay from the 1B2u(ππ*) state to the 1B3u(nπ*) and 1Au(nπ*) states, followed by oscillatory flow of population between the 1B3u(nπ*) and 1Au(nπ*) states, is interpreted by means of visualization of the potential energy curves and the reduced nuclear densities. By examining the electronic structure of the three valence-excited states and the final core-excited states, we observe that the population dynamics is explicitly reflected in the TR-NEXAFS spectra, especially when the heteroatoms are selected as the X-ray absorption sites. This work illustrates the feasibility of extracting fine details of molecular photophysical processes from TR-NEXAFS spectra by using currently available theoretical methods. [ABSTRACT FROM AUTHOR]

We present an experimental, self-consistent determination of the optical constants (refractive index) of Pt using a combination of photoabsorption and reflectance data in the photon energy range 25–778 eV, which includes the N- and O-shell electronic absorption edges of Pt. We compare our new experimental values with Pt optical constant data sets from the literature. Our Pt optical constant values reveal highly resolved absorption-edge fine structure around the O2,3 and N6,7 edges in both the absorptive and dispersive portions of the refractive index, which were missing in the earlier literature. [ABSTRACT FROM AUTHOR]

Whole white rice is a major staple food for human consumption, with its starch digestion rate and location in the gastrointestinal tract having a critical role for human health. Starch has a multi-scale structure, which undergoes order-disorder transitions during rice cooking, and this structure is a major determinant of its digestibility. The length distributions of amylose and amylopectin chains are important determinants of rice starch gelatinization properties. Starch chain-length and molecular-size distributions are important determinants of nucleation and crystal growth rates, as well as of intra- and intermolecular interactions during retrogradation. A number of first-order kinetics models have been developed to fit starch digestograms, producing new information on the structural basis for starch digestive characteristics of cooked whole rice. Different starch digestible fractions with distinct digestion patterns have been found for the digestion of rice starch in fully gelatinized and retrograded states, the digestion kinetics of which are largely determined by starch fine molecular structures. Current insights and future directions to better understand digestibility of starch in whole cooked rice are summarized, pointing to ways of developing whole rice into a healthier food by way of having slower starch digestibility. [ABSTRACT FROM AUTHOR]

Morphogenesis of many protozoans depends on a polarized establishment of cortical cytoskeleton containing the subpellicular microtubules (SPMTs), which are apically nucleated and anchored by the apical polar ring (APR). In malaria parasite Plasmodium, APR emerges in the host-invading stages, including the ookinete for mosquito infection. So far, the fine structure and molecular components of APR as well as the underlying mechanism of APR-mediated apical positioning of SPMTs are largely unknown. Here, we resolve an unprecedented APR structure composed of a top ring plus approximate 60 radiating spines. We report an APR-localizing and SPMT-binding protein APR2. APR2 disruption impairs ookinete morphogenesis and gliding motility, leading to Plasmodium transmission failure in mosquitoes. The APR2-deficient ookinetes display defective apical anchorage of APR and SPMT due to the impaired integrity of APR. Using protein proximity labeling, we obtain a Plasmodium ookinete APR proteome and validate ten undescribed APR proteins. Among them, APRp2 and APRp4 directly interact with APR2 and also mediate the apical anchorage of SPMTs. This study sheds light on the molecular basis of APR in the organization of Plasmodium ookinete SPMTs. The structure of subpellicular microtubules (SPMTs) nucleated from the apical polar ring (APR) is essential for Plasmodium parasite morphogenesis, gliding motility, and invasion. Here, Qian et al. characterize the function of APR2 protein in P. yoelii ookinetes. Using co-localization analysis, proximity labeling, CoIP, expansion microscopy and FRAP, they show that APR2 binds to SMPTs and has a fixed position in APR. Deletion mutants fail to traverse the mosquito midgut as they fail to anchor SPMTs on APR, which affects invasive morphology and gliding motility. [ABSTRACT FROM AUTHOR]

[Display omitted] • Starch fine molecular structure controls the eating and nutritional properties of cooked rice. • Shortcomings existed in current digestion and sensory experiments were discussed. • Starch fine molecular structures of amylose and amylopectin mutually associate. • Starch fine molecular structure-cooked rice functionality relations were concluded. White rice consumption has been regarded as a potential risk factor for non-communicable diseases including obesity and type 2 diabetes. Thus, increasing attention has been paid to develop slowly digested rices with acceptable palatability. As the most abundant component of rice kernels, the fine molecular structure of starch controls not only the texture & aroma, but also the digestion properties of cooked rice. A large number of studies have been conducted to see what molecular structural features control the digestibility and palatability of cooked rice, which further could be connected to starch biosynthesis to enable rices with targeted functionalities to be chosen in non-empirical ways. Nonetheless, little progress has been made because of improper experimental designs. For example, the effects of starch fine molecular structure on cooked rice digestibility and palatability has been rarely studied within one study, resulting to various digestion results. Even for the same sample, it is hard to obtain consistent conclusions and sometimes, the results/coclusions are even controversy. In this review paper, starch fine molecular structural effects on the texture, aroma and starch digestion properties of cooked white rice were summarized followed by a detailed discussion of the relations between the fine molecular structures of amylopectin and amylose to deduce a more general conclusion of starch molecular structure-cooked rice property relations. It is expected that this review paper could provide useful information in terms of how to develop slowly digested rices with acceptable palatability. [ABSTRACT FROM AUTHOR]

The structure of glycogen α particles in healthy mouse liver has two states: stability and fragility. In contrast, glycogen α particles in diabetic liver present consistent fragility, which may exacerbate hyperglycemia. Currently, the molecular mechanism behind glycogen structural alteration is still unclear. In this study, we characterized the fine molecular structure of liver glycogen α particles in healthy mice under time-restricted feeding (TRF) mode during a 24-h cycle. Then, differentially expressed genes (DEGs) in the liver during daytime and nighttime were revealed via transcriptomics, which identified that the key downregulated DEGs were mainly related to insulin secretion in daytime. Furthermore, GO annotation and KEGG pathway enrichment found that negative regulation of the glycogen catabolic process and insulin secretion process were significantly downregulated in the daytime. Therefore, transcriptomic analyses indicated that the structural stability of glycogen α particles might be correlated with the glycogen degradation process via insulin secretion downregulation. Further molecular experiments confirmed the significant upregulation of glycogen phosphorylase (PYGL), phosphorylated PYGL (p-PYGL), and glycogen debranching enzyme (AGL) at the protein level during the daytime. Overall, we concluded that the downregulation of insulin secretion in the daytime under TRF mode facilitated glycogenolysis, contributing to the structural stability of glycogen α-particles. [Display omitted] • The content and structure of liver glycogen changes diurnally in TRF mode. • DEGs of insulin secretion and glucose homeostasis were down-regulated in the daytime. • GO and KEGG analyses show down-regulation of insulin secretion in the daytime. • PYGL, p-PYGL, and AGL levels were upregulated in the daytime. • The glycogen degradation process co-occurs with glycogen α-particle stability. [ABSTRACT FROM AUTHOR]

Pump-probe near edge X-ray absorption fine structure (PP-NEXAFS) spectra of molecules offer insight into valence-excited states, even if optically dark. In PP-NEXAFS spectroscopy, the molecule is "pumped" by UV or visible light enforcing a valence excitation, followed by an X-ray "probe" exciting core electrons into (now) partially empty valence orbitals. Calculations of PP-NEXAFS have so far been done by costly, correlated wavefunction methods which are not easily applicable to medium-sized or large molecules. Here we propose an efficient, first principles method based on density functional theory in combination with the transition potential and ΔSCF methodology (TP-DFT/ΔSCF) to compute molecular ground state and PP-NEXAFS spectra. We apply the method to n → π* pump/O-K-edge NEXAFS probe spectroscopy of thymine (for which both experimental and other theoretical data exist) and to n → π* or π → π* pump/N-K-edge NEXAFS probe spectroscopies of trans- and cis-azobenzene. [ABSTRACT FROM AUTHOR]

The high-resolution photoelectron energy spectra of atomic titanium and its hydride anions were obtained on a slow-electron velocity-map imaging spectrometer equipped with a cold ion trap. The cold ion trap employed in the present measurement was found to be very helpful for reducing the interference from the titanium hydride anions. The electron affinity of Ti was determined to be 609.29(34) cm−1 or 75.54(4) meV. The accuracy was improved by a factor of 350 compared with the previous result. The fine structures of Ti− were clearly resolved: 70.0(12)(4F5/2), 165.2(15)(4F7/2), and 285.2(15) cm−1 (4F9/2) above its ground state 4F3/2. Moreover, the measured electron affinity and vibrational frequency of TiH can be reproduced well using the high level calculations. [ABSTRACT FROM AUTHOR]

A combination of high optical transparency and good electrical conductivity is realized in CuCrO2, a p-type transparent conducting oxide. With an aim to improve its physical properties, a CuCr1-xTixO2 (x=0, 0.05, 0.1) series was prepared and investigated for its structural, electrical transport, and optical properties. Along with the lattice parameter values, refinement of X-ray diffraction profiles confirm the solubility limit of Ti within the delafossite unit cell. Electrical resistivity and heat capacity measured by varying the temperature further characterize the Ti-substituted compositions. As determined from ultraviolet-visible spectroscopy, no significant changes take place in the optical gap of CuCrO2 with Ti addition. Apart from confirming the 4þvalence state of Ti, the X-ray absorption near edge structure highlights the subtle changes taking place in the Cu-O hybridization upon Ti-substitution. The analysis of temperature dependent extended X-ray absorption fine structure spectroscopy, recorded at the Cr and Cu K-edge, emphasizes the impact of redistribution of charges on the local crystal structure. Cu-Cu hybridization along the a-axis appears to be influenced mainly by the temperature and only slightly by Ti substitution. [ABSTRACT FROM AUTHOR]

Although the starch digestibility of cooked white rice has been investigated with regard to its relation to starch structure, it is not yet clear how starch molecular structure and water content affect its digestion rate. To investigate this, the in vitro starch digestibility and molecular structure of 10 rice varieties with a range of rice-to-water cooking ratios were investigated. As expected, starch digestibility varied with different conditions. Typically, a higher amylose content resulted in a lower maximum digestion extent for a given water content. Having relatively more and longer amylopectin intermediate chains caused a slower starch digestion rate, but only with rice-to-water ratios between 1:1 and 1:1.2. These results could prove useful to find combinations of starch fine molecular structures and water contents to produce cooked rice with low glycemic index. • Starch digestibility varied with different rice-to-water ratios. • A higher amylose content resulted in a lower maximum starch digestion extent. • More and longer amylopectin intermediate chains caused slower starch digestibility. • The above relations only hold with rice-to-water ratios between 1:1 and 1:1.2. [ABSTRACT FROM AUTHOR]

We have measured the resistance R(T, I, Bext) of a superconducting transition edge sensor over the entire transition region on a fine scale, producing a four-dimensional map of the resistance surface. The dimensionless temperature and current sensitivities (a ≡ ∂ log R/∂ log T|I and b ≡ ∂ log R/∂ log I|T) of the TES resistance have been determined at each point. a and b are closely related to the sensor performance, but show a great deal of complex, large amplitude fine structure over large portions of the surface that is sensitive to the applied magnetic field. We discuss the relation of this structure to the presence of Josephson "weak link" fringes. [ABSTRACT FROM AUTHOR]

Random packings of disks on a mesh are studied numerically using random sequential adsorption algorithm. The mesh is built of straight horizontal and vertical one-dimensional lines of a given distance between them. The packing fraction and structure as well as the kinetics of packing growth dependence on mesh size are analyzed to provide information, whether surface inhomogeneity will affect the properties of random packings. It has been shown that the number of disks in a packing slightly decreases with growing distance between mesh lines while the kinetics may change significantly even for very dense meshes. As packings obtained in random sequential adsorption resemble monolayers produced by irreversible adsorption processes, results of this study show that by measuring properties of a random packing it may be possible to determine fine structure of an underlying surface. [ABSTRACT FROM AUTHOR]

An extensive spectroscopic investigation of Kr+ plasma has been carried out through a comprehensive collisional-radiative plasma model along with the calculations of electron impact excitation cross-sections. The fully relativistic distorted wave method has been employed to calculate the detailed electron impact cross-sections for the transitions from the ground state, four metastable states of 4 p 4 4 d and a quasi-metastable state of 4 p 4 5 s to the fine structure levels of 4 p 4 n 1 s 7 ≤ n 1 ≤ 9 , 4 p 4 n 1 p , 4 p 4 n 2 d 6 ≤ n 2 ≤ 9 and 4 p 4 n 3 f 4 ≤ n 3 ≤ 9 excited states. For this purpose, the relativistic multi-configuration Dirac-Fock method is applied to compute the Kr+ ionic structure, Kr+ ion bound-state wave functions, excitation energies, oscillator strengths and transition probabilities. These results are compared with the previously reported values. Further, the complete set of electron impact excitation cross-sections has been incorporated in the collisional-radiative model along with the other relevant kinetic processes, viz. electron impact ionization, de-excitation, three-body recombination, and radiative decay. To validate the reliability of the electron collision data and the present collision radiative model, the measurements of Mar et al [J. Phys. B: At. Mol. Opt. Phys. 39 3,709 (2006)] at 40 μs and 90 μ s instants of plasma lifetime have been utilized for the diagnosis of experimentally measured pulsed discharge Kr+ plasma at 3.3 × 10 3 Pa. The measured line emissions from Kr+ in the wavelength range of 457–485 nm are compared with the intensities obtained from the present theoretical collision radiative model to obtain the plasma parameters such as electron temperature (T e) and electron density (n e). The electron temperature results at 40 μs and 90 μ s reported by Mar et al obtained through the Boltzmann plots, have been compared with the values obtained from the present collision radiative model. [Display omitted] • Developed a collisional radiative (CR) model for the diagnostics of Kr+ Plasma. • Electron excitation cross-section of Kr+ has been calculated for several states. • Relativistic bound state wave functions of Kr+ have been obtained using MCDF approach. • The excitation energies and transition parameters are reported. • The plasma parameters are reported at different instants of plasma lifetime. [ABSTRACT FROM AUTHOR]

Glycogen is a highly branched glucose polymer that is an energy storage material in fungi and animals. Extraction of glycogen from its source in a way that minimizes its molecular degradation is essential to investigate its native structure. In this study, the following extraction methods were compared: sucrose gradient density ultracentrifugation, thermal alkali, hot alcohol and hot water extractions. Molecular-size and chain-length distributions of glycogen were measured by size-exclusion chromatography and fluorophore-assisted carbohydrate electrophoresis, respectively. These two fine-structure features are the most likely structural characteristics to be degraded during extraction. The results show that the thermal alkali, hot alcohol and hot water extractions degrade glycogen molecular size and/or chain-length distributions, and that sucrose gradient density ultracentrifugation with neither high temperature nor alkaline treatment is the most suitable method for fungal glycogen extraction. [ABSTRACT FROM AUTHOR]

Though the retrogradation property as affected by starch fine molecular structures has been widely investigated, it remains largely unexplored how concurrent starch structures and storage conditions e.g. temperature tailor the starch retrogradation property. The amylopectin long-term retrogradation for 8 different rice starches with a broad range of amylose content was thus investigated under different storage temperatures. Results showed that gelatinized starch stored at −20 °C generally had a narrower melting temperature range from differential scanning calorimetry, while larger cells and thicker cell walls in the gel matrix than that stored at 4 °C. Different linear correlations were found between starch fine molecular structures and amylopectin retrogradation parameters when starch was stored under different temperatures. For example, the melting enthalpy of retrograded starch double helices was negatively correlated with the amount of amylose intermediate chains at 4 °C, while positively correlated with the relative length of amylopectin short chains at −20 °C. Under both temperatures, rice starch R250 had the highest retrogradation enthalpy. These results could help the rice industry improve both the nutritional and textural attributes of cooked rice by selecting starch with desirable molecular structures and optimizing the storage conditions for rice after cooking. [ABSTRACT FROM AUTHOR]

Waxy hull-less barley kernels and their isolated starches were exposed to different microwave conditions (power 640, 720, and 800 W, time 60, 120 and 180 s) and changes in morphology, particle size, digestibility, rheological properties, and molecular structure were measured and analyzed. Microwave treatment caused roughness and deformation of granular surfaces, and an increase in granule size. After treatment, the in vitro digestibility of starch was increased, i.e., the RDS increased, but the RS decreased. Microwave treatment decreased the K values of the in-kernel MWI WHBS. Dynamic rheological results showed that the in-kernel MWI WHBS pastes had lower T G ′max , and higher G ′ max , G ′ 90 °C , G ′ 25 °C , G ′ 0.1Hz and G ′ 20Hz after treatment. The chain-length distribution did not significantly change after microwave treatment. However, the results for molecular size distributions showed that the peaks of amylopectin (R h = ~100 nm) shifted left and right, indicating that the molecular volume might become smaller or larger under different processing conditions. The primary effects of microwave treatment may be loosening the molecular structure and cutting main chains of amylopectin. • Microwave irradiation was applied on starches from waxy hull-less barley. • Changes in molecular sizes of starch might affect their functional properties. • Microwave irradiation acted on loosening molecular structure and cutting C chains. [ABSTRACT FROM AUTHOR]

In this study, the effects of starch adjuncts with different fine molecular structures obtained by size-exclusion chromatography on the mashing and fermentation efficiencies of barley malts were investigated. Following fermentation, violate compounds of freshly-fermented beer samples were determined by headspace-solid-phase microextraction coupled with gas chromatography–mass spectrometry analysis (HS-SMPE-GC-MS). High performance liquid chromatography results showed that depending on their molecular structures, starch adjuncts addition significantly increased wort maltose and maltotriose content, whereas reducing the glucose content and thus both the ratios of glucose and maltotriose to that of the maltose. The whole fermentation by dry beer yeast was finished within the first 48 h and reached to equilibrium for the rest 72 h, represented by the stable soluble protein content. Results also showed that the addition of starch adjuncts resulted into increased alcohol content, which was mainly attributed to the altered glucose/maltose ratio. The HS-SPME-GC–MS results showed that whether or not with starch adjuncts addition, the composition of violate compounds were not significantly influenced, their content, on the contrary, were altered, represented by different peak heights. This study provides important information concerning the molecular effects of starch adjuncts on brewing performances of barley malts, and also provides a new pathway for choosing suitable types of adjuncts for making beer with better quality. • Starch adjuncts addition significantly increased maltose content after mashing. • Starch adjuncts addition significantly decreased glucose content after mashing. • Starch adjuncts addition increased the ethanol content after fermentation. • Starch adjuncts addition did not change the composition of beer violate compounds. [ABSTRACT FROM AUTHOR]

Resonance-enhanced multiphoton ionization (REMPI) is a widely used technique for studying molecular photoionization and producing molecular cations for spectroscopy and dynamics studies. Here, we present a model for describing hyperfine-structure effects in the REMPI process and for predicting hyperfine populations in molecular ions produced by this method. This model is a generalization of our model for fine- and hyperfine-structure effects in one-photon ionization of molecules presented in Paper I [M. Germann and S. Willitsch, J. Chem. Phys. 145, 044314 (2016)]. This generalization is achieved by covering two main aspects: (1) treatment of the neutral bound-bound transition including the hyperfine structure that makes up the first step of the REMPI process and (2) modification of our ionization model to account for anisotropic populations resulting from this first excitation step. Our findings may be used for analyzing results from experiments with molecular ions produced by REMPI and may serve as a theoretical background for hyperfine-selective ionization experiments. [ABSTRACT FROM AUTHOR]

We develop a model for predicting fine- and hyperfine intensities in the direct photoionization of molecules based on the separability of electron and nuclear spin states from vibrational-electronic states. Using spherical tensor algebra, we derive highly symmetrized forms of the squared photoionization dipole matrix elements from which we derive the salient selection and propensity rules for fineand hyperfine resolved photoionizing transitions. Our theoretical results are validated by the analysis of the fine-structure resolved photoelectron spectrum of O2 reported by Palm and Merkt [Phys. Rev. Lett. 81, 1385 (1998)] and are used for predicting hyperfine populations of molecular ions produced by photoionization. [ABSTRACT FROM AUTHOR]

Starch is the most abundant glycemic carbohydrate in the human diet. Consumption of starch‐rich food products that elicit high glycemic responses has been linked to the occurrence of noncommunicable diseases such as cardiovascular disease and diabetes mellitus type II. Understanding the structural features that govern starch digestibility is a prerequisite for developing strategies to mitigate any negative health implications it may have. Here, we review the aspects of the fine molecular structure that in native, gelatinized, and gelled/retrograded starch directly impact its digestibility and thus human health. We next provide an informed guidance for lowering its digestibility by using specific enzymes tailoring its molecular and three‐dimensional supramolecular structure. We finally discuss in vivo studies of the glycemic responses to enzymatically modified starches and relevant food applications. Overall, structure–digestibility relationships provide opportunities for targeted modification of starch during food production and improving the nutritional profile of starchy foods. [ABSTRACT FROM AUTHOR]

The rod and cone photoreceptor cells of the vertebrate retina have highly specialized structures that enable them to carry out their function of light detection over a broad range of illumination intensities with optimized spatial and temporal resolution. Most prominent are their unusually large sensory cilia, consisting of outer segments packed with photosensitive disc membranes, a connecting cilium with many features reminiscent of the primary cilium transition zone, and a pair of centrioles forming a basal body which serves as the platform upon which the ciliary axoneme is assembled. These structures form a highway through which an enormous flux of material moves on a daily basis to sustain the continual turnover of outer segment discs and the energetic demands of phototransduction. After decades of study, the details of the fine structure and distribution of molecular components of these structures are still incompletely understood, but recent advances in cellular imaging techniques and animal models of inherited ciliary defects are yielding important new insights. This knowledge informs our understanding both of the mechanisms of trafficking and assembly and of the pathophysiological mechanisms of human blinding ciliopathies. [ABSTRACT FROM AUTHOR]

The acetylenic CH stretch mode (v1) of propargyl (H2CCCH) radical has been studied at sub-Doppler resolution (~60 MHz) via infrared laser absorption spectroscopy in a supersonic slit-jet discharge expansion, where low rotational temperatures (Trot = 13.5(4) K) and lack of spectral congestion permit improved determination of band origin and rotational constants for the excited state. For the lowest J states primarily populated in the slit jet cooled expansion, fine structure due to the unpaired electron spin is resolved completely, which permits accurate analysis of electron spin-rotation interactions in the vibrationally excited states (εaa = -518.1(1.8), εbb = -13.0(3), εcc = -1.8(3) MHz). In addition, hyperfine broadening in substantial excess of the sub-Doppler experimental linewidths is observed due to nuclear spin-electron spin contributions at the methylenic (--CH2) and acetylenic (--CH) positions, which permits detailed modeling of the fine/hyperfine structure line contours. The results are consistent with a delocalized radical spin density extending over both methylenic and acetylenic C atoms, in excellent agreement with simple resonance structures as well as ab initio theoretical calculations. [ABSTRACT FROM AUTHOR]

A detailed quantum mechanical characterization of the photodissociation dynamics of H2O at 121.6 nm is presented. The calculations were performed using a full-dimensional wave packet method on coupled potential energy surfaces of all relevant electronic states. Our state-to-state model permits a detailed analysis of the OH(X /Ã) product fine-structure populations as a probe of the non-adiabatic dissociation dynamics. The calculated rotational state distributions of the two ?-doublet levels of OH(X, v = 0) exhibit very different characteristics. The A' states, produced mostly via the B ? X conical intersection pathway, have significantly higher populations than the A'' counterparts, which are primarily from the B ? Ã Renner-Teller pathway. The former features a highly inverted and oscillatory rotational state distribution, while the latter has a smooth distribution with much less rotational excitation. In good agreement with experiment, the calculated total OH(X) rotational state distribution and anisotropy parameters show clear even-odd oscillations, which can be attributed to a quantum mechanical interference between waves emanating from the HOH and HHO conical intersections in the B ? X non-adiabatic pathway. On the other hand, the experiment-theory agreement for the OH(A) fragment is also satisfactory, although some small quantitative differences suggest remaining imperfections of the ab initio based potential energy surfaces. [ABSTRACT FROM AUTHOR]

We present an extended X-ray absorption fine structure investigation of the local environment of Sn atoms in strained and relaxed Ge1-xSnx layers with different compositions. We show that the preferred configuration for the incorporation of Sn atoms in these Ge1-xSnx layers is that of a a-Sn defect, with each Sn atom covalently bonded to four Ge atoms in a classic tetrahedral configuration. Sn interstitials, Sn-split vacancy complexes, or Sn dimers, if present at all, are not expected to involve more than 2.5% of the total Sn atoms. This finding, along with a relative increase of Sn atoms in the second atomic shell around a central Sn atom in Ge1-xSnx layers with increasing Sn concentrations, suggests that the investigated materials are homogeneous random substitutional alloys. Within the accuracy of the measurements, the degree of strain relaxation of the Ge1-xSnx layers does not have a significant impact on the local atomic surrounding of the Sn atoms. Finally, the calculated topological rigidity parameter a**=0.69±0.29 indicates that the strain due to alloying in Ge1-xSnx is accommodated via bond stretching and bond bending, with a slight predominance of the latter, in agreement with ab initio calculations reported in literature. [ABSTRACT FROM AUTHOR]

Electronic spectra of organic molecules doped into superfluid helium nanodroplets show characteristic features induced by the helium environment. Besides a solvent induced shift of the electronic transition frequency, in many cases, a spectral fine structure can be resolved for electronic and vibronic transitions which goes beyond the expected feature of a zero phonon line accompanied by a phonon wing as known from matrix isolation spectroscopy. The spectral shape of the zero phonon line and the helium induced phonon wing depends strongly on the dopant species. Phonon wings, for example, are reported ranging from single or multiple sharp transitions to broad (△v > 100 cm-1) diffuse signals. Despite the large number of example spectra in the literature, a quantitative understanding of the helium induced fine structure of the zero phonon line and the phonon wing is missing. Our approach is a systematic investigation of related molecular compounds, which may help to shed light on this key feature of microsolvation in superfluid helium droplets. This paper is part of a comparative study of the helium induced fine structure observed in electronic spectra of anthracene derivatives with particular emphasis on a spectrally sharp multiplet splitting at the electronic origin. In addition to previously discussed species, 9-cyanoanthracene and 9-chloroanthracene will be presented in this study for the first time. [ABSTRACT FROM AUTHOR]

The current paper reports successful syntheses of Ni-TiN composite coatings by pulse electrodeposition. The effect of pulse frequency on the microstructures, nanomechanical, and wear properties of the coatings was investigated using transmission electron microscopy, X-ray diffraction, nanoindenter, scanning electron microscopy, and wear test instrument. The results showed that the Ni-TiN composite coating prepared at the pulse frequency of 100 Hz showed the presence of a less number of TiN particles and some degrees of aggregation in micro-regions. By contrast, in the Ni-TiN coating deposited at the pulse frequency of 500 Hz, the TiN particles were large in number and dispersed homogeneously, thereby, offering the coating a uniform and fine structure. The average grain diameters of Ni and TiN in the coating prepared at 100 Hz were 154.7 and 44.8 nm, respectively, whereas those for the coating prepared at 500 Hz were 67.3 and 25.9 nm, respectively. The maximum TiN content in the Ni-TiN coating deposited at 800 Hz was approximately 10.5 wt. %. The maximum microhardness and the Young's modulus values for the Ni-TiN composite coatings deposited at 800 Hz were 35.7 GPa and 167.4 GPa, respectively. Furthermore, the Ni-TiN composite coating prepared at 100 Hz had more severe damages, whereas the morphologies of worn surface of the coatings deposited at 500 Hz and 800 Hz were smooth and only a few small pits appeared on the surface. [ABSTRACT FROM AUTHOR]

Highland barley (HB) is mainly composed of starch, which may account for up to 65% of the dry weight to the kernel. HB possesses unique physical and chemical properties and has good industrial application potential. It has also been identified as a minor grain crop with excellent nutritional and health functions. Highland barley starch (HBS) features a number of structural and functional properties that render it a useful material for numerous food and non-food applications. This review summarizes the current status of research on the extraction processes, chemical composition, molecular fine structures, granular morphology, physicochemical properties, digestibility, chemical and physical modifications, and potential uses of HBS. The findings provide a comprehensive reference for further research on HBS and its applications in various food and non-food industries. [ABSTRACT FROM AUTHOR]

Sorghum steaming properties are important for both flavor and brewing efficiency of baijiu (Chinese alcohol liquor). However, it is currently unclear with respects to structural factors that affect sorghum steaming properties during baijiu production. In this study, starch fine molecular structures were characterized by size-exclusion chromatography and fluorophore-assisted carbohydrate electrophoresis for 8 sorghum varieties used in baijiu production. Starch crystalline structures and ordering of double helices were characterized by the X-ray diffraction and differential scanning calorimetry. Results showed that only small differences were observed for starch molecular size distributions and chain-length distributions in the raw sorghum flour. Of significance, the leached starch content and molecular size during steaming was very different among these sorghum varieties. Furthermore, Spearman correlation analysis showed that there was no significant correlation between starch fine structural parameters with the leached starch content. On the other hand, the correlation analysis showed that leached starch molecular size was negatively correlated with starch crystallinity, while positively correlated with the onset and peak gelatinization temperatures. It is concluded that the sorghum steaming property is controlled by the starch crystalline structures instead of starch fine molecular structures. These results could help the baijiu industry to produce baijiu with more desirable properties. • Sorghum steaming properties were investigated. • Small differences were observed for starch fine molecular structures of 8 sorghums. • Starch crystalline structure was significantly different. • The leached starch content was significantly different. • The leached starch molecular size was significantly different. [ABSTRACT FROM AUTHOR]

This study aimed to reveal the underlying mechanisms of the differences in viscoelasticity and digestibility between mung bean starch (MBS) and proso millet starch (PMS) from the viewpoint of starch fine molecular structure. The contents of amylopectin B2 chains (14.94–15.09 %), amylopectin B3 chains (14.48–15.07 %) and amylose long chains (183.55–198.84) in MBS were significantly higher than PMS (10.45–10.76 %, 12.48–14.07 % and 70.59–88.03, respectively). MBS with higher amylose content (AC, 28.45–31.80 %) not only exhibited a lower weight-average molar mass (91,750.65–128,120.44 kDa) and R 1047/1022 (1.1520–1.1904), but also was significantly lower than PMS in relative crystallinity (15.22–23.18 %, p < 0.05). MBS displayed a higher storage modulus (G′) and loss modulus (G′′) than PMS. Although only MBS-1 showed two distinct and discontinuous phases, MBS exhibited a higher resistant starch (RS) content than PMS (31.63–39.23 %), with MBS-3 having the highest RS content (56.15 %). Correlation analysis suggested that the amylopectin chain length distributions and AC played an important role in affecting the crystal structure, viscoelastic properties and in vitro starch digestibility of MBS and PMS. These results will provide a theoretical and scientific basis for the development of starch science and industrial production of low glycemic index starchy food. [Display omitted] • The crystal structure of mung bean starch (MBS) was weaker than proso millet starch (PMS). • High amounts of amylopectin short-chains weakened the viscoelastic properties of PMS. • MBS-1 with the lowest amylose content (AC) and h Am,ii reflected two digestion phases. • MBS reflected lower maximum starch digestibility and higher resistant starch content than PMS. • The amylopectin chain-length distributions and AC are the root cause of these differences. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fine structure of potato starch mediated with irradiation type was compared. • The digestograms of irradiated starch was fitted by a CPS kinetic model. • Irradiation preferentially destroyed the internal structure of large granules. • Increased double helix structure and semi-crystalline thickness increased RS content. • X-ray at higher doses was more able to damage structure and reduce digestibility. The change of digestibility of starch irradiated with different types from the perspective of fine structure is not well understood. In this work, the change of internal structure, molecular weight and chain-length distribution, helical structure, lamellar structure, fractal structure and digestibility of native and treated potato starch with electron beam and X-ray was analyzed. Two irradiations caused the destruction of internal structure, the disappearance of growth rings and increase of pores. Irradiation degraded starch to produce short chains and to decrease molecular weight. Irradiation increased double helical content and the thickness and peak area of lamellar structure, resulting in the reorganization of amylopectin and increase of structure order degree. The protected glycosidic linkages increased starch resistance to hydrolase attack, thereby enhancing the anti-digestibility of irradiated starch. Pearson correlation matrix also verified the above-mentioned results. Moreover, X-ray more increased the anti-digestibility of starch by enhancing ability to change fine structure. [ABSTRACT FROM AUTHOR]

The relationship between the fine structure of starch and its gelatinization properties is not well studied, particularly in relation to the influence of sugar or sugar alcohol. In this study, seven starches with distinct molecular structures were investigated to determine how different sugars and sugar alcohols affect their gelatinization properties. The inclusion of sugars and sugar alcohols resulted in a significant elevation of starch gelatinization temperatures (∼ 8 °C), especially with sucrose, isomaltose and isomalt. Nevertheless, the influence of these sugars/ sugar alcohols on the gelatinization temperature range and enthalpy change varied depending on the particular starch varieties. According to the correlation analysis, sugars and sugar alcohols mainly exert their impact on the starch gelatinization temperature range and enthalpy change by possibly interacting with amylose chains possessing a degree of polymerization ranging from 100 to 1000 (p < 0.05) and inhibiting the amylose leaching during gelatinization. These findings help a better understanding of the complex relationship between starch fine structure and gelatinization properties under the influence of sugars and sugar alcohols. Possible mechanism how sugars and sugar alcohols affect starch gelatinization property. [Display omitted] [ABSTRACT FROM AUTHOR]

• Spine structural plasticity is mediated by the reorganization of molecular structure. • Optical technologies advance our understanding of spine structure and plasticity. • CRISPR tools hold new promise for precisely imaging underlying molecular processes. The structural plasticity of dendritic spines is considered to be essential for various forms of synaptic plasticity and, ultimately, learning and memory. The process is mediated by signaling pathways that promote the reorganization of the actin cytoskeleton and subsynaptic structures, which in turn cause structural and functional changes in dendritic spines. Recent advances in optical technologies have started to reveal the fine molecular structures and dynamic signaling occurring inside spines, providing significant insights into the molecular regulation of spines. Here, we highlight recent studies to resolve the molecular mechanisms underlying the spine actin cytoskeleton and plasticity with high spatiotemporal resolution. Moreover, we discuss new genome editing-based approaches in imaging the molecular structure and plasticity of dendritic spines. [ABSTRACT FROM AUTHOR]

Pea starches, in both native (NPS) and retrograded-autoclaved forms (RAPS), were subjected to simulated gastrointestinal (GI) digestion in vitro , their multi-scale structural characteristics, morphological features, molecular distribution and thermal properties were characterized. A gradual increase in the short−/long-range crystallinity, melting enthalpy of gelatinization on increasing digestion time was observed for both the native and retrograded-autoclaved pea starch samples based on the X-ray diffraction, Fourier-transform infrared spectra, solid-state 13CNMR and differential scanning calorimetry measurements. It was especially noticed that the growth rate of crystallinity and double helices, as well as the decrease in M w values were evidently greater for RAPS than for NPS. To investigate how different molecular fine structure of pea starch substrate affects the gut microbiota shifts and dynamic short-chain fatty acid profile, their resistant starch residues obtained from both native and retrograded-autoclaved pea starch after 8 h of simulated GI tract digestion was used as the fermentation substrate. The levels of acetate, propionate and butyrate gradually increased with the increasing fermentation time for NPS and RAPS. In comparison to the blank control (i.e. , the group without the addition of carbohydrate), the fermented NPS and RAPS obviously resulted in an increased abundance of Firmicutes and Bacteroidetes , accompanied by a decrease in Proteobacteria , Actinobacteria and Verrucomicrobia. Both NPS and RAPS promoted different shifts in the microbial community at the genus level, with an increase in the abundance of Bacteroides , Megamonas and Bifidobacterium , as well as a reduction in the abundance of Fusobacterium , Faecalibacterium and Lachnoclostridium in comparison to the blank control samples. • A gradual increase in crystallinity of pea starch residue on increasing digestion time was observed. • The increase of crystallinity was greater for autoclaved pea starch than its native form. • SCFA were overall higher for fermentable autoclaved pea starch than its native counterpart. • Taxonomy-based microbial abundance showed divergent shifts with different treatments. [ABSTRACT FROM AUTHOR]