Search

Given a Riemannian metric on a compact smooth manifold, we consider its Schouten tensor, which is a tensor field of type (0, 2) arising in the remainder of the Weyl part in the standard decomposition of the curvature tensor of the metric. We study extremal properties of the Schouten functional, defined to be the scaling-invariant L-norm of the Schouten tensor. It is proved, for instance, that space form metrics are characterized as critical points of the Schouten functional among conformally flat metrics. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we study locally strongly convex affine hypersurfaces of that have parallel cubic form with respect to the Levi-Civita connection of the affine Berwald–Blaschke metric; it is known that they are affine spheres. In dimension we give a complete classification of such hypersurfaces; in particular, we present new examples of affine spheres. [Copyright &y& Elsevier]

We show that a Riemannian metric on a 4-dimensional smooth manifold is of constant scalar curvature if and only if it is a critical metric of the restricted Schouten functional. [ABSTRACT FROM AUTHOR]

There exists a well known construction which allows to associate with two hyperbolic affine hyperspheres $$f_{i} : M^{n_{i}}_{i} \rightarrow {\mathbb{R}}^{n_{i}+1}$$ a new hyperbolic affine hypersphere immersion of $$I \times M_{1} \times M_{2}$$ into $${\mathbb{R}}^{n_{1}+n_{2}+2}$$ . In this paper we deal with the inverse problem: how to determine from properties of the difference tensor whether a given hyperbolic affine hypersphere immersion of a manifold $$M^{n} \rightarrow R^{n+1}$$ can be decomposed in such a way. [ABSTRACT FROM AUTHOR]

Let M n( n ≥ 2) be an immersed umbilic-free hypersurface in the ( n+1)-dimensional unit sphere S n+1. Then M n is associated with a so-called Möbius metric g, and a Möbius second fundamental form B which are invariants of M nunder the Möbius transformation group of S n+1. In this paper, we classify all umbilic-free hypersurfaces with parallel Möbius second fundamental form. [ABSTRACT FROM AUTHOR]

In this paper, we study hypersurfaces of the homogeneous NK (nearly Kähler) manifold S 3 × S 3. As the main results, we first show that the homogeneous NK S 3 × S 3 admits neither locally conformally flat hypersurfaces nor Einstein Hopf hypersurfaces. Then, we establish a Simons type integral inequality for compact minimal hypersurfaces of the homogeneous NK S 3 × S 3 and, as its direct consequence, we obtain new characterizations for hypersurfaces of the homogeneous NK S 3 × S 3 whose shape operator A and induced almost contact structure ϕ satisfy A ϕ = ϕ A. Hypersurfaces of the NK S 3 × S 3 satisfying this latter condition have been classified in our previous joint work (Hu et al. 2018 [18]). [ABSTRACT FROM AUTHOR]

Plant proteins, serving as an environmentally friendly and cost-effective alternative to animal proteins, have gained widespread usage in encapsulating various bioactive compounds like curcumin. However, understanding how plant protein-based microcapsules compare to those made with animal proteins in terms of disintegration, release, and absorption in the gastrointestinal tract (GIT) remains limited. This study aims to investigate the impact of soy protein isolate (SPI) and whey protein isolate (WPI) as wall materials on the release, stability, and absorption of curcumin. Spray-dried SPI-based microcapsules (SPI–C) exhibited significantly lower encapsulation efficiency (77.1%) and loading efficiency (3.6%) compared to WPI-based microcapsules (WPI–C) (97.6% and 9.6%, respectively). Structural analysis revealed pleated hollow spherical structures for SPI-C and a concave surface with a single-chamber structure for WPI-C. SPI-C demonstrated higher proteolysis (55.8% vs. 44.1%) during in vitro digestion, leading to greater curcumin release ratio (67.9% vs. 59.2%) and digestive stability (97.9% vs. 93.7%) compared to WPI-C. Notably, SPI-C exhibited higher apparent permeability (0.97 × 10−6 cm/s) to the ex vivo rat small intestine than WPI-C (0.44 × 10−6 cm/s). These findings suggest improved gastrointestinal stability and absorption of curcumin encapsulated by SPI, indicating the potential for enhanced utilization of plant-derived proteins in encapsulating bioactive compounds. • Spray-dried curcumin microcapsules prepared with SPI and WPI as wall materials. • SPI-C showed lower encapsulation efficiency and loading efficiency than WPI-C • Enhanced digestive stability of curcumin when encapsulated by SPI compared to WPI. • The curcumin release positively correlated with wall protein hydrolysis. • SPI-C displayed higher apparent permeability to the ex vivo rat small intestine than WPI-C [ABSTRACT FROM AUTHOR]

Based on ionospheric total electron content (TEC) data for Zhongshan station (ZHS) and Scott Base station (SBA) in Antarctica, acquired during 2010–2020, high-latitude ionospheric TEC diurnal variations of two near cusp latitude stations were studied. The magnetic latitude and longitude differences between the two stations were approximately 5° and 135°, respectively. It was found that during the 11-year solar activity cycle, the maximum diurnal variation of the ionospheric TEC at ZHS occurred mainly between local noon and magnetic noon. Statistically, the TEC peaks occurred closer to local (magnetic) noon under low (high) solar activity conditions. The maximum diurnal variation of ionospheric TEC at SBA occurred mainly around local noon under low solar activity conditions but before magnetic midnight under high solar activity conditions. The effects of solar radiation, particle precipitation, and polar ionospheric convection pattern on the diurnal variation of TEC were investigated. At both stations, photoionization caused by solar radiation was the main reason for the maximum diurnal variation of ionospheric TEC around local noon. During high solar activity with high concentration plasma in the dayside polar ionosphere, the convection pattern was the dominant influence on the maximum diurnal variation of TEC before magnetic midnight (noon) at SBA (ZHS). [ABSTRACT FROM AUTHOR]

Measurements of Very-Low-Frequency (VLF) transmitter signals have been widely used to investigate the effects of various space weather events on the D-region ionosphere, including nowcasting solar flares. Previous studies have established a method to nowcast solar flares using VLF measurements, but only using measurements from dayside propagation paths, and there remains limited focus on day–night mixed paths, which are important for method applicability. Between March and May of 2022, the Sun erupted a total of 56 M-class and 6 X-class solar flares, all of which were well captured by our VLF receiver in Antarctica. Using these VLF measurements, we reexamine the capability of the VLF technique to nowcast solar flares by including day–night mixed propagation paths and expanding the path coverage in longitude compared to that in previous studies. The amplitude and phase maximum changes are generally positively correlated with X-ray fluxes, whereas the time delay is negatively correlated. The curve-fitting parameters that we obtain for the X-ray fluxes and VLF signal maximum changes are consistent with those in previous studies for dayside paths, even though different instruments are used, supporting the flare-nowcasting method. Moreover, the present results show that, for day–night mixed paths, the amplitude and phase maximum changes also scale linearly with the logarithm of the flare X-ray fluxes, but the level of change is notably different from that for dayside paths. The coefficients used in the flare-nowcasting method need to be updated for mixed propagation paths. [ABSTRACT FROM AUTHOR]

• A novel bionic 'colon' soft-elastic reactor (CSER) including morphology and motion of the human colon. • The bottom-to-top transport mode is possible in the current bionic 'colon' reactor. • The segmental propulsion frequency largely influenced the emptying of agar gel particles in the CSER. • The agar gel particles with greater fracture force took longer to be emptied in the CSER. • CSER can simulate the bottom-to-top chyme transport as that occurring in the ascending colon. A novel colon soft-elastic reactor (CSER), inspired by the human ascending colon and cecum, has been developed and investigated using a model product system. This CSER replicates the behavior of the ascending colon in humans, achieving both peristalsis and segmental propulsion. The design of the bionic colon model is based on silicone and adopts a bag-like structure resembling colon anatomy. Peristalsis and segmental propulsion are simulated using a unique mechano-electric setup. Varying the depth of rolling motion resulted in different breakages of agar gel particles. Increasing the squeezing depth of the rollers against the silicone wall from 70 % to 100 % led to an increase in small-sized particles (< 3.5 mm) from 6.5 % to 66.7 % of the total particle mass. Moreover, increasing the frequency of segmental propulsion from 3.3 to 38.6 times/h reduced the half-life (t 1/2) of agar gel particles from 137.9 to 0.4 min. The t 1/2 was significantly higher for the 3.0 wt% agar gel (207.4 min) compared to the 1.0 wt% agar gel (113.5 min). During CSER squeezing, solid agar gel particles move upward while liquid flows downward along the wall due to gravity. These findings demonstrate the CSER effectively simulates bottom-to-top chyme transport in the ascending colon. [Display omitted] [ABSTRACT FROM AUTHOR]

In this paper, studying locally strongly convex flat elliptic centroaffine hypersurfaces in R n + 1 , we first give a centroaffine geometric characterization of the hypersurface x n + 1 = 1 2 x 1 ∑ i = 2 n x i 2 + x 1 ln ⁡ x 1. Then, restricted to n = 3 , we establish the classification of flat elliptic centroaffine Tchebychev hypersurfaces in R 4. The latter is an extension of the result of Lalléchère et al. (2021) [8] which classified flat hyperbolic centroaffine Tchebychev hypersurfaces in R 4. [ABSTRACT FROM AUTHOR]

In this paper, we study Hopf hypersurfaces of the two Kähler surfaces S 2 × S 2 and H 2 × H 2. First, we classify real hypersurfaces of S 2 × S 2 and H 2 × H 2 with their shape operator A and induced almost contact structure ϕ satisfying A ϕ + ϕ A = ρ ϕ for a constant ρ. Then, we classify real hypersurfaces of H 2 × H 2 with isometric Reeb flow. Finally, we classify Hopf hypersurfaces of S 2 × S 2 and H 2 × H 2 with constant Reeb function as well as with recurrent Ricci tensor. [ABSTRACT FROM AUTHOR]

Aurora spectral data, the particular hyperspectral data of auroral spectra, have an irreplaceable research value in bridging the gap between solar activity and terrestrial evolution. Their requirement for high-volume storage and real-time transmission had been a great challenge until we proposed a CPU-paralleled and online-biprediction-based method. As it is no longer applicable because of the recent spectrograph reassembling, this paper presents a replacement strategy combines the unidirectional predictor with the entropy coder of the other dimension, as well as with using smoothing and outlier recognition. The hybrid encoders of Spat-SPCC and Spec-SPCC are developed distinguished by their respective prediction direction. Spat-SPCC tuned on one-day trial data is used for its better capability for compression, in the further comparison with various classical algorithms, it achieves the top-ranking compression performance and has the average processing time of 1 s per file so that its availability for the practical applications is validated. [ABSTRACT FROM AUTHOR]

Auxin is an important phytohormone in plants, and auxin signaling pathways in rice play key roles in regulating its growth, development, and productivity. To investigate how rice grain yield traits are regulated by auxin signaling pathways and to facilitate their application in rice improvement, we validated the functional relationships among regulatory genes such as OsIAA10, OsSK41, and OsARF21 that are involved in one of the auxin (OsIAA10) signaling pathways. We assessed the phenotypic effects of these genes on several grain yield traits across two environments using knockout and/or overexpression transgenic lines. Based on the results, we constructed a model that showed how grain yield traits were regulated by OsIAA10 and OsTIR1, OsAFB2, and OsSK41 and OsmiR393 in the OsSK41‐OsIAA10‐OsARF module and by OsARF21 in the transcriptional regulation of downstream auxin response genes in the OsSK41‐OsIAA10‐OsARF module. The population genomic analyses revealed rich genetic diversity and the presence of major functional alleles at most of these loci in rice populations. The strong differentiation of many major alleles between Xian/indica and Geng/japonica subspecies and/or among modern varieties and landraces suggested that they contributed to improved productivity during evolution and breeding. We identified several important aspects associated with the genetic and molecular bases of rice grain and yield traits that were regulated by auxin signaling pathways. We also suggested rice auxin response factor (OsARF) activators as candidate target genes for improving specific target traits by overexpression and/or editing subspecies‐specific alleles and by searching and pyramiding the 'best' gene allelic combinations at multiple regulatory genes in auxin signaling pathways in rice breeding programs. [ABSTRACT FROM AUTHOR]

Spikelet number per panicle (SNP) is one of the most important yield components in rice. Rice ENHANCING BIOMASS AND SPIKELET NUMBER (OsEBS), a gene involved in improved SNP and yield, has been cloned from an accession of Dongxiang wild rice. However, the mechanism of OsEBS increasing rice SNP is poorly understood. In this study, the RNA-Seq technology was used to analyze the transcriptome of wildtype Guichao 2 and OsEBS over-expression line B102 at the heading stage, and analysis of the evolution of OsEBS was also conducted. A total of 5369 differentially expressed genes (DEGs) were identified between Guichao2 and B102, most of which were down-regulated in B102. Analysis of the expression of endogenous hormone-related genes revealed that 63 auxin-related genes were significantly down-regulated in B102. Gene Ontogeny (GO) enrichment analysis showed that the 63 DEGs were mainly enriched in eight GO terms, including auxin-activated signaling pathway, auxin polar transport, auxin transport, basipetal auxin transport, and amino acid transmembrane transport, most of which were directly or indirectly related to polar auxin transport. Kyoto Encyclopedia of Genes and Genomes (KEGG) metabolic pathway analysis further verified that the down-regulated genes related to polar auxin transport had important effects on increased SNP. Analysis of the evolution of OsEBS found that OsEBS was involved in the differentiation of indica and japonica, and the differentiation of OsEBS supported the multi-origin model of rice domestication. Indica (XI) subspecies harbored higher nucleotide diversity than japonica (GJ) subspecies in the OsEBS region, and XI experienced strong balancing selection during evolution, while selection in GJ was neutral. The degree of genetic differentiation between GJ and Bas subspecies was the smallest, while it was the highest between GJ and Aus. Phylogenetic analysis of the Hsp70 family in O. sativa, Brachypodium distachyon, and Arabidopsis thaliana indicated that changes in the sequences of OsEBS were accelerated during evolution. Accelerated evolution and domain loss in OsEBS resulted in neofunctionalization. The results obtained from this study provide an important theoretical basis for high-yield rice breeding. [ABSTRACT FROM AUTHOR]

The theory of equatorward moving east-west elongated auroral arcs associated with field line resonance (FLR) has been proposed for decades. However, confirming this theory requires in-situ observations of FLR within the magnetosphere and simultaneous all-sky imager observations of equatorward moving auroral arcs near satellite footpoints. In this study, we present the first observations of multiple equatorward moving auroral arcs related to impulse-excited FLR, using datasets from the WIND, Geotail satellites, and an all-sky imager at China's Zhongshan Station (ZHS) in Antarctica. In the presented event, the ultra-low-frequency waves associated with solar wind dynamic pressure pulse was mainly toroidal mode, which is consistent with the theory that the toroidal mode waves usually related with external source. The all-sky imager located in Zhongshan station recorded several equatorward moving auroral arcs, followed by reverse propagating ones. The latitudinal width of the equatorward moving auroral arcs was on the order of 25 km and had an average equatorward propagation of ~0.37 km/s, which is very similar to the value from previous work. To better illustrate the observed evolution of auroral arcs related with the FLRs we proposed a simple model to evaluate the FACs induced by the FLRs in different latitudes. The latitudinal distribution evolution of FACs agrees well with the ground-based optical observations. [ABSTRACT FROM AUTHOR]

The black aurora is a distinct phenomenon characterized by spatially well-defined regions where the diffuse auroral luminosity decreases notably. Typically, black auroras present as arcs moving at lower velocities, patches with higher moving speeds, and arc segments. However, the mechanism behind black auroras remains unclear. In this paper, we present a novel observation of a poleward-moving black auroral arc associated with impulse-excited field-line resonances in the dawnside sector from the multi-spacecraft THEMIS (Time History of Events and Macroscale Interactions during Substorms) mission, equivalent ionospheric currents, and a conjugated all-sky imager. The field-line resonance velocities exhibit periodic vorticity, which correspond to periodic poleward-moving bands of enhanced FACs. Based on the relatively large reduction in luminosity, we conclude that the poleward-moving black auroral arc was most likely caused by downward FACs associated with field-line resonances. [ABSTRACT FROM AUTHOR]

The Earth's magnetospheric cusp, a region with an off-equatorial magnetic field minimum, is an important place which directly transports plasma and energy from the solar wind into the magnetosphere and ionosphere. Its magnetic topology and charged particles therein are known to respond to the solar wind and the interplanetary magnetic field. However, its dynamics in response to the interplanetary (IP) shock are still unknown, due to lack of direct spacecraft observations. This study first reports the observations of the cusp's motion under the drive of an IP shock and both strong electric fields and outflowing energetic ions in the moving cusp. After an IP shock arrival on 7 September 2017, triple cusps were observed by Cluster C4 when it was crossing the high-altitude northern polar region to the sub-solar magnetosphere. The multiple cusps had a one-to-one correspondence with the dayside magnetosphere compression and relaxation detected by THEMIS E, indicating that one cusp moved back and forth three times due to the IP shock's impact. In the moving cusp, there were strong impulsive electric fields with a peak of up to ∼40 mV/m and an ionospheric source population of upward propagating ions (O + , He + and H + ) with energies extending to MeV. However, the outflowing ions outside the cusp had energies of no more than 1 keV. An enhancement of energetic O + appeared inside the cusp with the flux ratio of O + /H + increasing from 10 keV to ∼ MeV, which implies the efficient acceleration of O + . These observations are shown to be consistent with the prompt acceleration by the impulsive electric fields, which is mass-dependent. This finding suggests a new acceleration mechanism for cusp energetic ions, especially for O + . [ABSTRACT FROM AUTHOR]

Solar flares have a severe impact on the near-earth space environment, during which the VLF signals observed by the ground-based instrument exhibit abnormal changes. However, the similarity and differences of VLF signal responses to solar flares over daytime and nighttime propagation paths are still unclear. Previous magnetograph measurements suggest that solar flares can also influence the dark hemisphere by the induction currents caused by the change in the ionospheric electrical conductivity of the sunlit hemisphere. To examine these effects, we have analyzed the solar flare effects on VLF propagation along two paths that are suited along the north–south direction, but with a time difference of 12 h. From late March to late May in the year of 2022, a total of 32 flare events with clear VLF responses are selected in order to analyze the similarity and differences between daytime and nighttime propagation paths. Different from the previous magnetograph measurements, it is found that the solar flare effects can only be observed from daytime VLF propagation paths. Moreover, present results show that the amplitude and phase variation of the VLF signal increases almost linearly with the magnitude of solar flares, and the stronger the solar flare, the more obvious the influence on VLF signals. However, the two paths exhibit notably different sensitivity in terms of amplitude and phase variation to solar flare class. Future studies that aim at nowcasting solar flare events using ground-based VLF receivers need to take these effects into account. The goal is to better understand the effects of solar flares on the lower ionosphere, with a view toward improving the nowcasting capability of the VLF technique for solar flares. [ABSTRACT FROM AUTHOR]

Abstract: We present an automatic method to recognize the poleward moving auroras (PMAs) from all-sky image sequences. A simplified block matching algorithm combined with an orientation coding scheme and histogram statistics strategy was utilized to estimate the auroral motion between interlaced images. An all-sky image sequence was first modeled by hidden Markov models (HMMs) and then represented by HMM similarities. The imbalanced classification problem, i.e., non-PMA events far outnumbering PMA events, was addressed by the metric-driven biased support vector machine (SVM). The proposed method was evaluated using auroral observations in 2003 at the Chinese Yellow River Station. Five days observations were manually labeled as PMA or non-PMA events considering both the keogram and all-sky image information. The supervised classification experiments were carried out and achieved satisfactory results. We further detected PMAs from auroral observations in the remaining days and the resultant double-peak occurrence distribution was compared with that of the well-known poleward moving auroral forms (PMAFs). [Copyright &y& Elsevier]

Heading date is an important agronomic trait in rice (Oryza sativa L.). We previously fine‐mapped two complementary genes, Late Heading Date 1 and Late Heading Date 2 (LH2), that control the late heading trait in rice. Here, we cloned and analyzed the function of LH2. LH2 was fine‐mapped to a 53‐kb genomic region. Sequencing analysis revealed that there were differences in the coding sequence of LOC_Os08g07740 between the varieties 'Bo B' and 'Yuefeng B'. Therefore, LOC_Os08g07740 was identified as a candidate gene for LH2 and subsequently determined that LH2 is a Type 3 allele of Days To Heading 8. Transgenic plants of Yuefeng B carrying LH2 from Bo B significantly delayed the heading date under short‐day and long‐day conditions. A yeast two‐hybrid analysis revealed that LH2 physically interacted with Heme Activator Protein (HAP) 5A, ‐H, ‐I, ‐L, ‐K, and HAP5‐LIKE. The HAP5 domain of HAP5 family members has various functions. Further analysis revealed that LH2 represses photoperiodic flowering by controlling the expression of Early Heading Date 1, Heading date 3a, and Rice Flowering Locus T1 in rice. Core Ideas: LH2 delayed heading by 17.6 d in short‐day conditions and >32.7 d in long‐day conditions.LH2 physically interacted with HAP5A, ‐H, ‐I, ‐L, ‐K, and HAP5‐LIKE.The HAP5 domain of the HAP5 family exhibited functional differentiation.LH2 is a Type 3 allele of DTH8. [ABSTRACT FROM AUTHOR]

Abstract: Addressing the transmission and storage problems of aurora images that Arctic Yellow River Station of China faces, the present paper proposes a two-stage lossless compression algorithm based on weighted motion compensation and context-based modeling. As no specialized compression algorithms for aurora images are available, proposing a new algorithm that offers a satisfactory lossless compression performance for aurora images is necessary. The proposed algorithm utilizes the weighted motion compensation to obtain the motion vector based on the unusual movement characteristics of aurora images. Subsequently, the context-based model is combined with the motion vector. Experimental results indicated that the proposed algorithm outperformed the state-of-the-art lossless compression methods. [Copyright &y& Elsevier]

Studying the well-known phenomenon "aurora" plays a pivotal role in investigating the solar–terrestrial coupling mechanism. A special auroral spectrograph in Antarctic Zhongshan Station constitutes a auroral observation joint system with satellite-borne sensors of the Defense Meteorological Satellite Program. Multipoint observation by this system provides more essential information for relevant studies than single observation by each instrument, but also results in a multifold increased volume of data that are difficult to be either stored or transmitted. To address this difficulty, we develop a clustering-based, generic lossless data compression framework that combines the usage of various ultimate compressors with a hierarchical clustering algorithm to exert the strength of all the compressors in data reduction. This framework achieves an always-best compression performance for different-sized datasets with a reasonable time consumption, which promises the design of pipelines using it for real-time data transmission. [ABSTRACT FROM AUTHOR]

Docosahexaenoic acid (DHA), an essential omega-3 fatty acid, offers significant health benefits but faces challenges such as distinct odor, oxidation susceptibility, and limited intestinal permeability, hindering its broad application. Microencapsulation, widely employed, enhances DHA performance by facilitating controlled release, digestion, and absorption in the gastrointestinal tract. Despite extensive studies on DHA microcapsules and related delivery systems, understanding the mechanisms governing encapsulated DHA release, digestion, and absorption, particularly regarding the influence of wall materials and DHA sources, remains limited. This review starts with an overview of current techniques commonly applied for DHA microencapsulation. It then proceeds to outline up-to-date advances in the release, digestion and absorption of DHA microcapsules, highlighting the roles of wall materials and DHA sources. Importantly, it proposes strategies for overcoming challenges and exploiting opportunities to enhance the bioavailability of DHA microcapsules. Notably, spray drying dominates DHA microencapsulation (over 90 % usage), while complex coacervation shows promise for future applications. The combination of proteins and carbohydrates or phospholipids as wall material exhibits potential in controlling release and digestion of DHA microcapsules. The source of DHA, particularly algal oil, demonstrates higher lipid digestibility and absorptivity of free fatty acids (FFAs) than fish oil. Future advancements in DHA microcapsule development include formulation redesign (e.g., using plant proteins as wall material and algal oil as DHA source), technique optimization (such as co-microencapsulation and pre-digestion), and creation of advanced in vitro systems for assessing DHA digestion and absorption kinetics., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Food and formulation characteristics are crucial factors affecting the gastrointestinal release and absorption kinetics of oral solid preparations. In the present study, the dynamic continuous release and bioaccessibility of metformin hydrochloride immediate-release (IR) and sustained-release (SR) tablets were investigated in the dynamic human stomach-intestine (DHSI-IV) system simulating fasted and fed states in healthy adults. Both tablet formulations (particularly IR tablet) exhibited a postponed release in the fed state compared to the fasted state. Correspondingly, the bioaccessible fraction of metformin from IR tablets in the presence of high-fat meal was significantly reduced to 76.2 % of the fasted state. However, the in vitro bioaccessibility was less impaired by food for SR tablets with a fed/fasted ratio of 95.5 %. A convolution-based approach was used to convert in vitro bioaccessibility results to plasma concentration data. The predicted plasma concentration curve showed good agreement with human data in terms of pharmacokinetic (PK) parameters. In the fasted state, the predicted C max , T max and AUC 0-24h of IR tablets were 943.9 ± 25.7 ng/mL, 2.0 ± 0.4 h and 7090.7 ± 112.0 ng.h/mL, respectively, mirroring values observed in healthy subjects. Overall, the DHSI-IV system has demonstrated potential to assess and predict the impact of meal intake on the in vivo release and absorption behaviors of oral solid preparations., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Amylose content (AC) is the main factor determining the palatability, viscosity, transparency, and digestibility of rice (Oryza sativa) grains. AC in rice grains is mainly controlled by different alleles of the Waxy (Wx) gene. The AP2/EREBP transcription factor OsEBP89 interacts with the MYC-like protein OsBP5 to synergistically regulate the expression of Wx. Here, we determined that the GLYCOGEN SYNTHASE KINASE 5 (OsGSK5, also named SHAGGY-like kinase 41 [OsSK41]) inhibits the transcriptional activation activity of OsEBP89 in rice grains during amylose biosynthesis. The loss of OsSK41 function enhanced Wx expression and increased AC in rice grains. By contrast, the loss of function of OsEBP89 reduced Wx expression and decreased AC in rice grains. OsSK41 interacts with OsEBP89 and phosphorylates four of its sites (Thr-28, Thr-30, Ser-238, and Thr-257), which makes OsEBP89 unstable and attenuates its interaction with OsBP5. Wx promoter activity was relatively weak when regulated by the phosphomimic variant OsEBP89 E -OsBP5 but relatively strong when regulated by the nonphosphorylatable variant OsEBP89 A -OsBP5. Therefore, OsSK41-mediated phosphorylation of OsEBP89 represents an additional layer of complexity in the regulation of amylose biosynthesis during rice grain development. In addition, our findings provide four possible sites for regulating rice grain AC via precise gene editing., (© 2023 The Authors. Journal of Integrative Plant Biology published by John Wiley & Sons Australia, Ltd on behalf of Institute of Botany, Chinese Academy of Sciences.)

Intestinal permeability is a key factor affecting the bioavailability and physiological efficacy of docosahexaenoic acid (DHA) encapsulated in microcapsules. However, how the DHA microcapsules are transformed and the components absorbed across the small intestinal membrane has seldom been examined previously. In this study, an ex vivo absorption model based on the permeability of the rat small intestine was established to evaluate the intestinal absorption of DHA microcapsules with five formulations after gastrointestinal digestion in vitro . For pure glucose solutions, the apparent permeability coefficient ( P app ) increased from 5.70 ± 0.60 × 10 -6 cm s -1 at 5 mg mL -1 to 20.25 ± 0.88 × 10 -6 cm s -1 at 30 mg mL -1 and decreased to 15.73 ± 0.91 × 10 -6 cm s -1 at 100 mg mL -1 . The P app values obtained using the ex vivo model are comparable to those reported in the human jejunum. For algal oil DHA microcapsules with whey protein as the wall material (A-WP-DHA) after in vitro digestion, the P app of glucose released was 3.81 × 10 -6 cm s -1 with an absorption ratio of 59.55% in the ex vivo model, significantly lower than that from the in vitro porcine casing model. The P app and absorption ratio varied little among the in vitro dialysis models with different molecular weight cut-off values. A similar trend was observed for the absorption of amino acids. However, the absorption ratio (26.6%) was the highest in the ex vivo model for free fatty acids (FFAs) released from the microcapsules due to the rapid accumulation of compounds on the inner wall of the intestinal sac. In addition, the DHA microcapsules with algal oil as the DHA source (36.40%) exhibited a higher absorption ratio of FFAs than that from tuna oil (14.26%) in the ex vivo model. The wall material compositions seemed to have little effect on FFA absorption. The present study is practically meaningful for the future formulation of DHA microcapsules with enhanced absorption.

Microencapsulation is a promising technique to improve the bioavailability and mask the unpleasant smell of DHA oils. Yet, how the encapsulated DHA oils are 'released' and 'digested' within the gastrointestinal tract (GIT) and the effect of the wall material and source of DHA have been largely unknown. Here, two commercial DHA microcapsules from algae oil (A-DHA) and tuna oil (T-DHA) with 100% whey protein (WP) and 80% casein and 20% WP (C-WP) as wall materials were evaluated in vitro respectively. The release ratio was nearly linearly increased to 77.7% and 41.7% after the simulated gastric phase for T-DHA and A-DHA microcapsules, respectively. In contrast to A-DHA microcapsules for which the release of DHA approached equilibrium in the later intestinal phase, a decline in the release ratio was shown for T-DHA microcapsules perhaps due to the interaction of T-DHA with bile salts resulting in the formation of micelles. The more stable release behaviors might suggest a better performance of A-DHA coated by WP, which enables sustainable release during GIT digestion. This is supported by the better ability to resist gastric proteolysis for A-DHA microcapsules. Additionally, T-DHA (27.5%) showed a lower lipid digestibility than A-DHA (68.5%) in the end due to their structure difference. Significantly positive correlations were found for both microcapsules between DHA release ratio and protein hydrolysis. This study has provided quantitative information on the in vitro release and digestion of DHA microcapsules as influenced by the wall protein and DHA source. The findings are practically meaningful for future formulation of DHA microcapsules with controlled release rates at target sites of the GIT.

Rice embryos are rich in high-quality protein, lipid, vitamins and minerals, representing the most important nutritional part of brown rice. However, the molecular mechanism of rice embryo development is poorly understood. In this study, two rice cultivars with contrasting embryo size (the giant embryo cultivar Dapeimi and the normal embryo cultivar 187R) were used to explore excellent genes controlling embryo size, and the developed near-isogenic lines (NILs) (NIL-D, which has the giant embryo phenotype, and its matching line, NIL-X) were used to explore transcript and metabolic properties in the earlier maturation stage of giant embryo development under natural conditions. The map-based cloning results demonstrated that Dapeimi is a novel allelic mutant of the rice GIANT EMBRYO ( GE ) gene, and the functional mutation site is a single cytosine deletion in the exon1. A total of 285 differentially accumulated metabolites (DAMs) and 677 differentially expressed genes (DEGs) were identified between NIL-D and NIL-X. The analysis of DAMs indicated that plants lacking GE mainly promoted energy metabolism, amino acid metabolism, and lipid metabolism pathways in the rice embryo. Pearson correlation coefficient showed that 300 pairs of gene-metabolites were highly correlated. Among them, OsZS&#95;02G0528500 and OsZS&#95;12G0013700 were considered to be key genes regulating L-Aspartic acid and L-Tryptophan content during rice giant embryo development, which are promising to be good candidate genes to improve rice nutrition. By analyzing rice embryo development through a combination of strategies, this research contributes to a greater understanding of the molecular mechanism of rice embryo development, and provides a theoretical foundation for breeding high-nutrition varieties., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Hu, Xiong, Wang, Zhang, Yan, Cao, Niu, Zhu, Hu and Wu.)

Plant architecture is an important agronomic trait that affects crop yield. Here, we report that a gene involved in programmed cell death, OsPDCD5 , negatively regulates plant architecture and grain yield in rice. We used the CRISPR/Cas9 system to introduce loss-of-function mutations into OsPDCD5 in 11 rice cultivars. Targeted mutagenesis of OsPDCD5 enhanced grain yield and improved plant architecture by increasing plant height and optimizing panicle type and grain shape. Transcriptome analysis showed that OsPDCD5 knockout affected auxin biosynthesis, as well as the gibberellin and cytokinin biosynthesis and signaling pathways. OsPDCD5 interacted directly with OsAGAP, and OsAGAP positively regulated plant architecture and grain yield in rice. Collectively, these findings demonstrate that OsPDCD5 is a promising candidate gene for breeding super rice cultivars with increased yield potential and superior quality., Competing Interests: The authors declare no competing interest.