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Background: To date, the magnitude of association and the quality of evidence for cognitive decline (mild cognitive impairment, Alzheimer's disease, and dementia) in couples and risk factors for outcomes have not been reviewed and analyzed systematically. Objective: The aim of this study was to investigate the concordance of cognitive impairment in unrelated spouses and to qualitatively describe potential risk factors. Methods: Eight databases were searched from inception to October 20, 2023. Eligible studies were independently screened and assessed for quality. Statistical analysis was conducted using Stata 15.1 software. The study was preregistered with PROSPERO (CRD42023488024). Results: Eleven studies involving couples were included, with moderate to high evidence quality. Compared to controls, spouses of individuals with cognitive impairment had lower cognitive scores (Cohen's d: 0.18-0.62) and higher risk of cognitive decline (OR = 1.42, 95% CI: 1.15–1.76). The consistency of cognitive impairment between spouses was attributed to three theories: 1) the impact of caregiving stress experienced by the spouse; 2) assortative mating, which suggests that individuals select partners with similar characteristics; and 3) the influence of shared living environments and lifestyles. Conclusions: The cognitive status of one spouse can affect the cognitive function of the other spouse. It is important to consider shared lifestyle, environmental, and psychobehavioral factors, as they may contribute to the risk of cognitive decline by couples. Identifying these factors can inform the development of targeted recommendations for interventions and preventive measures. [ABSTRACT FROM AUTHOR]

Agrocybe aegerita , one of the edible mushroom varieties, is popular among consumers for its umami taste. Umami peptides, including EV, EG, EY, ENG, ECG, DEL, DDL, PEG, PEEL, DGPL, and EDCS are the main umami compounds in A. aegerita. In this study, when the concentration of these 11 umami peptides was 5 mg/mL, the corresponding relative umami intensity (measured by MSG concentration) ranged from 4.457 to 5.240 mg/mL, with DDL being the highest. All umami peptides exhibited better umami taste under neutral and weakly acidic conditions (pH 6-7). EY and ENG, with a higher umami intensity at 70 °C, were more suitable for a wide application in thermally processed foods. Additionally, the relationship between the structure and strength of umami peptides was explored using a three-dimensional quantitative structure-activity relationship model with an R2 of 0.987. Overall, umami peptides in A. aegerita possess strong potential for application in food processing. • The stability and umami intensity of 11 umami peptides have been explored. • DDL and DEL have the highest relative umami intensity. • Umami peptides have higher umami intensity under neutral or weak acidic condition. • Low-concentration umami peptides exhibit prominent umami enhancement. • The 3D-QASR model has been used to explain the structure-activity of umami peptide. [ABSTRACT FROM AUTHOR]

Folates play an important role in plant metabolism. Here we report a T-DNA insertion mutant ( atdfb-3 ) of the plastidial folylpolyglutamate synthetase gene ( AtDFB ) was defective in folate metabolism and nitrogen metabolism under nitrate-limited conditions in darkness. Exogenous applied 5-formyl-tetrahydrofolate (5-F-THF) completely restored nitrogen content, soluble protein, total amino acids, individual amino acids including Glu, Gln, Asp, Asn, Pro, Arg and Met, nitrate, and endogenous 5-F-THF in atdfb-3 to the wild-type level. At the same time the application of 5-F-THF partially restored the content of Ser and nitrite in the mutant. Taken together, these results indicated that intact folate metabolism was necessary for nitrogen metabolism in Arabidopsis thaliana under nitrate-limited condition in darkness, providing novel insights into function of folate. [ABSTRACT FROM AUTHOR]

Interactions among metabolic pathways are important in plant biology. At present, not much is known about how folate metabolism affects other metabolic pathways in plants. Here we report a T-DNA insertion mutant (atdfb-3) of the plastidial folylpolyglutamate synthetase gene (AtDFB) was defective in seed reserves and skotomorphogenesis. Lower carbon (C) and higher nitrogen (N) content in the mutant seeds than that of the wild type were indicative of an altered C and N partitioning capacity. Higher levels of organic acids and sugars were detected in the mutant seeds compared with the wild type. Further analysis revealed that atdfb-3 seeds contained less total amino acids and individual Asn and Glu as well as NO3−. These results indicate significant changes in seed storage in the mutant. Defects in hypocotyl elongation were observed in atdfb-3 in darkness under sufficient NO3− conditions, and further enhanced under NO3− limited conditions. The strong expression of AtDFB in cotyledons and hypocotyl during early developmental stage was consistent with the mutant sensitivity to limited NO3− during a narrow developmental window. Exogenous 5-formyl-tetrahydrofolate completely restored the hypocotyl length in atdfb-3 seedlings with NO3− as the sole N source. Further study demonstrated that folate profiling and N metabolism were perturbed in atdfb-3 etiolated seedlings. The activity of enzymes involved in N reduction and assimilation was altered in atdfb-3. Taken together, these results indicate that AtDFB is required for seed reserves, hypocotyl elongation and N metabolism in darkness, providing novel insights into potential associations of folate metabolism with seed reserve accumulation, N metabolism and hypocotyl development in Arabidopsis. [ABSTRACT FROM AUTHOR]

Background: Unfavorable temperatures significantly constrain the quality formation of Dendrobium officinale, severely limiting its food demand. Salicylic acid (SA) enhances the resistance of D. officinale to stress and possesses various analogs. The impact and mechanism of the SA family on improving the quality of D. officinale under adverse temperature conditions remains unclear. Results: Combined with molecular docking analysis, chlorophyll fluorescence and metabolic analysis after treatments with SA analogues or extreme temperatures are performed in this study. The results demonstrate that both heat and cold treatments impede several main parameters of chlorophyll fluorescence of D. officinale, including the ΦPSII parameter, a sensitive growth indicator. However, this inhibition is mitigated by SA or its chemically similar compounds. Comprehensive branch imaging of ΦPSII values revealed position-dependent improvement of tolerance. Molecular docking analysis using a crystal structure model of NPR4 protein reveals that the therapeutic effects of SA analogs are determined by their binding energy and the contact of certain residues. Metabolome analysis identifies 17 compounds are considered participating in the temperature-related SA signaling pathway. Moreover, several natural SA analogs such as 2-hydroxycinnamic acid, benzamide, 2-(formylamino) benzoic acid and 3-o-methylgallic acid, are further found to have high binding ability to NPR4 protein and probably enhance the tolerance of D. officinale against unfavorable temperatures through flavone and guanosine monophosphate degradation pathways. Conclusions: These results reveal that the SA family with a high binding capability of NPR4 could improve the tolerance of D. officinale upon extreme temperature challenges. This study also highlights the collaborative role of SA-related natural compounds present in D. officinale in the mechanism of temperature resistance and offers a potential way to develop protective agents for the cultivation of D. officinale. [ABSTRACT FROM AUTHOR]

Background: Unfavorable temperatures significantly constrain the quality formation of Dendrobium officinale, severely limiting its food demand. Salicylic acid (SA) enhances the resistance of D. officinale to stress and possesses various analogs. The impact and mechanism of the SA family on improving the quality of D. officinale under adverse temperature conditions remains unclear. Results: Combined with molecular docking analysis, chlorophyll fluorescence and metabolic analysis after treatments with SA analogues or extreme temperatures are performed in this study. The results demonstrate that both heat and cold treatments impede several main parameters of chlorophyll fluorescence of D. officinale, including the ΦPSII parameter, a sensitive growth indicator. However, this inhibition is mitigated by SA or its chemically similar compounds. Comprehensive branch imaging of ΦPSII values revealed position-dependent improvement of tolerance. Molecular docking analysis using a crystal structure model of NPR4 protein reveals that the therapeutic effects of SA analogs are determined by their binding energy and the contact of certain residues. Metabolome analysis identifies 17 compounds are considered participating in the temperature-related SA signaling pathway. Moreover, several natural SA analogs such as 2-hydroxycinnamic acid, benzamide, 2-(formylamino) benzoic acid and 3-o-methylgallic acid, are further found to have high binding ability to NPR4 protein and probably enhance the tolerance of D. officinale against unfavorable temperatures through flavone and guanosine monophosphate degradation pathways. Conclusions: These results reveal that the SA family with a high binding capability of NPR4 could improve the tolerance of D. officinale upon extreme temperature challenges. This study also highlights the collaborative role of SA-related natural compounds present in D. officinale in the mechanism of temperature resistance and offers a potential way to develop protective agents for the cultivation of D. officinale. [ABSTRACT FROM AUTHOR]

Bacterial cellulose(BC) is a kind of extracellular polymer synthesized by bacteria and it has very wide applications in many fields. However, the application of BC in a large commercial scale can still not be fulfilled due to the low yield and demanding for BC membranes with very different properties. To this end, a new BC-producer Komagataeibacter rhaeticus TJPU03 was isolated from rotten orange peel, which produced 8.28 ± 0.27 g/L(dry weight) in standard HS medium at the 10th day. The membrane is easier to be purified by one-step alkaline treatment and the produced BC(K - BC) membranes possess homogeneous, looser and more porous three-dimensional network composed by thinner cellulose fibrils. However, the wet K-BC possesses stronger mechanical properties and exhibits lower toxicity and higher cytocompatibility to mammalian cell. Owing to the more porous and homogeneous network, K-BC possesses high loading capacity of cell and protein drugs. Also, it exhibits sustained-controlled release ability for proteinaceous drug. The high yield of this strain and the special characteristics of K - BC predict this strain to be a very promising BC-producer and broad applications of K-BC in the fields of wound healing, scaffolds of tissue engineering, tissue repair and regeneration. Image 1 • A novel BC producing strain is obtained. • BC produced by this strain possesses novel properties. • This BC has great potential for drug delivery carrier. [ABSTRACT FROM AUTHOR]

ObjectiveMethodsResultsConclusionsThis study aims to examine the effect of the Mediterranean diet (MeDi) on cognitive decline among the Chinese elderly with a 3-year follow-up.This study is divided into two waves: wave-1 January 2019 to June 2019 (n = 2313); wave-2 January 2022 to March 2022 (n = 1648). MeDi scores were calculated from the Mediterranean Diet Adherence Screener (MEDAS), with the scoring of low compliance (0–6 points) and high compliance (7–14 points). The Mini-Mental State Examination (MMSE) was used to assess cognitive function. An MMSE score dropping ≥ 2 points from baseline was defined as cognitive decline. The relationships between MeDi score and cognitive decline were analyzed by linear regression models or Binary logistic regression.During the 3-year follow-up, 23.8% of patients exhibited cognitive decline. The study revealed a significant difference in MMSE score changes between low and high MeDi adherence groups (p < 0.001). MeDi score was negatively correlated with cognitive deterioration (β = −0.020, p = 0.026). MeDi score was only negatively associated with cognitive decline in the female subgroup aged ≥65 years (β = −0.034, p = 0.033). The food beans (OR = 0.65, 95%CI:0.51, 0.84), fish (OR = 0.72, 95%CI:0.54, 0.97), and cooked vegetables (OR = 0.68, 95%CI:0.53, 0.84) were protective factors for cognitive decline.This study suggests that greater adherence to the MeDi is linked to a reduced risk of cognitive decline in elderly people. However, this is found only in women who are 65 years old or older. It also found long-term adherence to beans, fish, and vegetables are more effective in improving cognitive function. [ABSTRACT FROM AUTHOR]

The poor mechanical properties of self-healing hydrogels limited their applications in the fields of biomedicine and industry. Here, a series of self-healing polymeric ionic liquid (PIL) hydrogels with high mechanical strength and electrical conductivity were prepared through hydrophobic association. Hydrophilic monomer vinyl ionic liquids (VILs) based on choline and amino acids, acrylamide (AAm) and hydrophobic monomers stearyl methacrylate (C18) were copolymerized in a micellar solution of sodium dodecyl sulfate (SDS); meanwhile, bacterial cellulose was introduced to enhance the mechanical strength of hydrogels. The resultant hydrogels exhibited excellent mechanical strength (5.8 MPa), extensive elongation at break (4250%) and outstanding self-healing efficiency (85%) without any external intervention. Even after healing, the tensile strength of most hydrogels could reach 2.5–3.9 MPa. At the same time, the incorporation of ILs endowed hydrogels with good electrical conductivity (a maximum of 1.258 S/m). These excellent properties predicted the potential application of the obtained PIL hydrogels in the fields of biomedicine and industry. [ABSTRACT FROM AUTHOR]

Background: Patient-centered health care for patients with pulmonary hypertension (PH) is important and requires an understanding of patient experiences. However, there is a lack of approaches to examine what's the effects and how the disease impact patients' psychological well-beings. Methods: We conducted qualitative interviews with PH patient representatives to understand patient psychological experiences and inform patient-centered research and care. Participants were chosen from a tertiary hospital located in northwest China. 20 patients with PH who be treated at the hospital (13 participants were women, aged 18-74 years) were strategically selected and individually interviewed. We used qualitative analysis to identify themes relating to existential psychological distress that would clarify the nature of such concerns. Results: We found that patients experience tremendous psychological distress throughout the treatment process. Four categories that describe patients' psychological experiences emerged: burden of PH treatment, fear and uncertainty about the disease, frustration in social and family role, and lack of recognition of the condition. Conclusions: Existential concerns are salient in PH and involve the experience of loss and disruptions to the sense of self and relationships. Healthcare practitioners must work more in collaboration to detect patients' need for support and to develop the patient's own skills to manage daily life. The PH teams should tailor interventions to provide emotional, informational and instrumental support and guidance to patients. [ABSTRACT FROM AUTHOR]

Root rot of Paris polyphylla has received widespread attention due to its threat to yield and leads to serious economic losses. However, the relationship among the rhizosphere microbial community, metabolites and root rot disease remained largely unexplored. Herein, we used integrated 16S rRNA, ITS, RNA sequencing and UPLC-MS/MS to systematically investigate the differences between healthy and diseased P. polyphylla. We found that root rot reduced the microbial diversity in the diseased P. polyphylla compared with the healthy control. The relative abundance of the bacterial phylum Actinobacteria increased in the diseased rhizome of P. polyphylla. For the fungal community, root rot disease contributed to an increased relative abundance of Ascomycota and decreased Glomeromycota at the phylum level. The transcriptomic results showed that the differently expressed genes were significantly enriched in the "Biosynthesis of various alkaloids", "flavonoid biosynthesis" and "isoflavonoid biosynthesis" and "Phenylpropanoid biosynthesis" was dramatically enriched in healthy P. polyphylla compared with that in diseased P. polyphylla. Likewise, the metabolomic results showed that the biosynthesis of secondary metabolites and metabolic pathways was found to be significantly enriched by differential metabolites. Taken together, the study of combining metabolomics with microbiomes can help us enhance our understanding of the mechanisms of plant resistance to root rot disease, thereby discovering specific metabolites and microorganisms that can resist pathogen infection in P. polyphylla. [ABSTRACT FROM AUTHOR]

This paper presents the common methods and corresponding drawbacks concerning nonlinear analysis of fluxgate excitation circuits and emphasizes the importance of nonlinear analysis for these circuits. With regard to the nonlinearity of the excitation circuit, this paper proposes the use of the core-measured hysteresis curve for mathematical analysis and the use of a nonlinear model that considers the coupling effect of the core and winding and influence of the historical magnetic field on the core for simulation analysis. The feasibility of mathematical calculations and simulation for the nonlinear study of fluxgate excitation circuit is verified via experiments. The results demonstrate that, in this regard, the simulation is four times better than a mathematical calculation. The simulation and experimental results of the excitation current and voltage waveforms under different excitation circuit parameters and structures are essentially consistent, with a difference in current of no more than 1 mA, thereby verifying the effectiveness of the nonlinear excitation analysis method. [ABSTRACT FROM AUTHOR]

In this study, to explore the relationship between environmental factors and fungal diversity in the Shenzhen River ecosystem, multiple methods including chemical analysis, culture isolation, qPCR analysis of fungal ITS region and ITS-based Illumina next-generation-sequencing were integrated. A total of 115 isolates were finally isolated and could be classified into 23 genera. Top three abundant genera isolated were Meyerozyma (18 strains), Aspergillus (17 strains) and Penicillium (14 strains). Based on the Illumina sequencing approach, 829 OTUs were affiliated to seven phyla, 17 known classes, and 162 genera, indicating the Shenzhen estuary sediments are rich in fungal diversity. The major fungal genera were Meyerozyma, Trichoderma and Talaromyces. Environmental factors showed a gradient change in Shenzhen estuary, and fungal abundance was only significantly correlated with NH4+. Shannon index was significantly correlated with pH and IC (P < 0.05). Principal coordinate analysis based on OTU level grouped into three clusters among sampling sites along with the IC and pH gradient. Functional guilds analysis suggests most of the fungi in this studying area were almost all saprotrophs, suggesting a large number of saprophytic fungi may play a significant role in the organic matter decomposition and nutrient cycling process. In summary, this study will deepen our understanding of fungi community in Shenzhen River ecosystem and their distribution and potential function shaped by environmental factors. [ABSTRACT FROM AUTHOR]

As an effective active remote sensing technology for the exploration of shallow underground targets, ground-penetrating radar (GPR) is a detection method that can be used to obtain information about the characteristics of underground targets by transmitting an electromagnetic wave from an antenna and analyzing the propagation of the electromagnetic wave underground. Due to the frequency (1 MHz–3 GHz) of GPRs, the depth of geological exploration is shallow (0.1–30 m). In order to penetrate the deeper Earth, it is necessary to increase the size of the antenna in accordance with the wavelength ratio and, thus, reduce the radiation frequency. For most bi-static antenna GPRs, a dipole antenna is used as the transmitting antenna and another antenna device is used as a receiving antenna, with both being horizontally linearly polarized (LP) antennas. In some cases, such a design can cause problems, such as the multi-path effect and polarization mismatching. When a GPR is used for deep exploration, increased numbers of errors and greater signal attenuation during data reception and processing often occur. In contrast, at the radiation source, with the use of large-aperture multiple-dipole antennas and multi-channel sequential rotational excitation, the electromagnetic wave can radiate in the form of circular polarization at a low frequency. In the receiving antenna, the issues caused by the multi-path effect and polarization mismatching can be addressed, even if LP antennas are used. A novel sequential rotationally excited (SRE) circularly polarized (CP) multiple-dipole array for a bi-static antenna GPR for deep exploration is proposed in this paper. A large-aperture CP multiple-dipole array is used instead of a small-size LP dipole antenna. The analysis and simulation results demonstrated that, comparing circular polarization and linear polarization with the premise of the same transmitting power, the SRE CP multiple-dipole antenna array radiation source achieved a significant enhancement (about 7 dB) in the signal-to-noise ratio (SNR) as the radiant energy was collected at the receiving antenna. More importantly, by reducing the exploration frequency to 10 KHz, the exploration depth could also be greatly increased by about tenfold. [ABSTRACT FROM AUTHOR]

• Using a depth camera for unilateral point cloud collection and preprocessing. • A new point cloud repairment for beef cattle based on moving least squares. • A novel approach for measuring body sizes using unilateral information. Body measurements of beef cattle at various growth stages are crucial for assessing breeding quality. To decrease the stress responses of live cattle during measurement, noncontact body size measurement using a deep sensor is conducted. After directly obtaining the point cloud data (PCD) of a unilateral surface, novel point cloud repair and body measurement are proposed. The PCD of beef cattle are first preprocessed using Euclidean clustering, conditional filtering, and Random Sample Consensus. To merge the unilateral PCD into the entire contour, a Euclidean transformation matrix and moving least squares are applied. To address holes caused by stitching due to camera angle restrictions, various upsampling techniques based on least squares deformation are investigated to repair holes in different surfaces with varying growth stages. Finally, polynomial fitting is chosen to be in accordance with the feature point distribution of the body height (BH), chest girth (CG), back height (AH), waist height (WH), ischial tuberosity, and shoulder end of beef cattle. Using the formulas of Euclidean distance and cubic B–spline curve fitting, the values of BH, AH, WH, CG, and body length are obtained and then compared with manual measurement data. The predicted values of the five body sizes of 100 beef cattle had a mean absolute error and mean absolute percentage error of 7.77 cm and 5.42 %, respectively. The largest absolute error was 12.05 cm, and the smallest absolute error was 4.12 cm. A series of PCD processing and repair methods provides a new method for the noncontact automated measurement of beef cattle. This approach promotes more effective practices in livestock welfare and trait assessment compared with traditional management. [ABSTRACT FROM AUTHOR]

We propose a versatile tunable terahertz (THz) absorber based on vanadium dioxide (VO 2) and graphene, and studied the absorption properties of absorber using the finite difference time domain (FDTD) method. It was found that by adjusting the conductivity of VO 2 via temperature, the absorber can exhibit narrowband or wideband absorption. When the VO 2 is kept in room temperature it has low conductivity and is in insulating state, the absorber operates in a narrowband absorption mode. When the temperature of VO 2 is higher than 68 °C it is in the metallic state, the absorber shows a wideband absorption. In addition, the amplitude of absorption can be adjusted easily by changing the Fermi energy level (E F) of graphene. When the VO 2 is in insulating state，and the E F of graphene is set at 1.2 eV, the terahertz absorber shows a strongest narrowband absorption with a peak at 5.25 THz. When the VO 2 is in metallic state，the terahertz absorber can achieve wideband absorption exceeding 90 % in 1.48–3.62 THz range. Furthermore, we analyzed the absorption mechanism of the absorber using impedance matching theory and transmission line theory, and investigated the influence of incident angle on absorption spectra. Finally, we validated the capability of metasurfaces as a biosensor by detecting avian influenza viruses. [Display omitted] • The absorption rate of the absorber can be independently tuned over a wider range. • The absorber enables dual tuning of absorption rate and bandwidth. • The proposed absorber can be used as a biosensor. [ABSTRACT FROM AUTHOR]

Salicylic acid is a commonly used anti-spoilage agent to prevent browning and quality degradation during potato processing, yet its precise mechanism remains unclear. This study elucidates the role of StuPPO2, a functional protein in Favorita potato shreds, in relation to the anti-browning and starch degradation effects of 52 SA analogues. By employing molecular docking and Gaussian computing, SA localizes within the hydrophobic cavity of StuPPO2, facilitated by hydroxyl and carboxyl groups. The inhibitory effect depends on the distribution pattern of the maximal electrostatic surface potential, requiring hydroxyl ion potentials of >56 kcal/mol and carboxyl ion potentials of >42 kcal/mol, respectively. Multiomics analysis, corroborated by validation tests, indicates that SA synthetically suppresses activities linked to defense response, root regeneration, starch degradation, glycoalkaloids metabolism, and potato shred discoloration, thereby preserving quality. Furthermore, SA enhances antimicrobial and insect-repellent aromas, thereby countering biotic threats in potato shreds. These collective mechanisms underscore SA's anti-spoilage properties, offering theoretical foundations and potential new anti-browning agents for agricultural preservatives. [Display omitted] • The anti-browning of salicylic acid analogues correlate with starch degradation. • Salicylic acid localizes to hydrophobic cavity of polyphenol oxidase 2. • The electrostatic potential of hydroxyl and carboxyl is crucial for salicylic acid. • Salicylic acid regulates multiomic profiles to preserve shredded potato. • Salicylic acid regulates potato odors to challenge biotic threats. [ABSTRACT FROM AUTHOR]

We proposed a chiral metasurface which can realize absorption, circular dichroism (CD) and line-to-circular polarization conversion (LTC-PC). Additionally, by varying the Fermi energy level (E f) of graphene, the amplitude of the absorption can be changed for specific application. CD can also be dynamically tuned by adjusting the conductivity of photosensitive silicon (PS). Furthermore, by rotating the meta-atom of the chiral metasurface, Panchalatnam-Berry (PB) phase can be obtained. By designing different reflection phase distributions, dynamically tunable anomalous reflections, vortex beams, and focusing can be realized. This design offers new methodologies for optical modulators, communications, image processing, and other related fields. • The absorption can be dynamically tuned. • The circular dichroism can be dynamically adjusted. • Line to circularly polarized wave conversion is realized. • The metasurface can realize anomalous reflections, vortex beams and focusing. [ABSTRACT FROM AUTHOR]

Chloroplast formation is associated with embryo development and seedling growth. However, the relationship between chloroplast differentiation and embryo development remains unclear. Five FtsHi genes that encode proteins with high similarity to FtsH proteins, but lack Zn2+-binding motifs, are present in the Arabidopsis genome. In this study, we showed that T-DNA insertion mutations in the Arabidopsis FtsHi4 gene resulted in embryo arrest at the globular-to-heart–shaped transition stage. Transmission electron microscopic analyses revealed abnormal plastid differentiation with a severe defect in thylakoid formation in the mutant embryos. Immunocytological studies demonstrated that FtsHi4 localized in chloroplasts as a thylakoid membrane-associated protein, supporting its essential role in thylakoid membrane formation. We further showed that FtsHi4 forms protein complexes, and that there was a significant reduction in the accumulation of D2 and PsbO (two photosystem II proteins) in mutant ovules. The role of FtsHi4 in chloroplast development was confirmed using an RNA-interfering approach. Additionally, mutations in other FtsHi genes including FtsHi1, FtsHi2, and FtsHi5 caused phenotypic abnormalities similar to ftshi4 with respect to plastid differentiation during embryogenesis. Taken together, our data suggest that FtsHi4, together with FtsHi1, FtsHi2, and FtsHi5 are essential for chloroplast development in Arabidopsis. [ABSTRACT FROM AUTHOR]

The endosperm is an essential part of the seed which sustains embryo development and contains storage reserves. Endosperm development involves a series of nuclear divisions in the absence of cytokinesis. In this study, it is shown that a mutant Arabidopsis plant carrying the disrupted At4g24900 gene exhibits severe defects during seed development. At4g24900 encodes a nuclear-localized C2H2-containing protein and the transcripts of this gene are alternatively spliced, consequently producing at least nine differentially spliced isoforms. The heterozygous T-DNA insertion mutation in this gene resulted in abortion of 25% of seeds, and the homozygous mutant allele displayed embryo lethality. Differential interfernce contrast (DIC) analyses revealed that the mutant has endosperm nuclei with more than one nucleolus and an embryo arrested at the globular to heart stage transition. Because this mutant exhibits a titan-like phenotype, it was designated ttl. The TTL gene is preferentially expressed in tissues with quickly dividing cells as revealed in PTTL::GUS (β-glucuronidase) transgenic plants. It is proposed that TTL is likely to function as a key regulator of endosperm nuclear division. [ABSTRACT FROM PUBLISHER]

As a semifermented tea, oolong is exceedingly popular worldwide for its elegant, flowery aroma and mellow, rich taste. However, recent marketing trends for old oolong teas and their chemical quality largely remain unexplored. In this study, we applied widely targeted metabolomics using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) combined with multivariate analysis to investigate the chemical change of oolong teas in the aging process. With the increasing of store time, most nongalloylated catechins; tannins, including TFs and proanthocyanidins; flavonols and glycosylated flavonols; amino acids and their derivatives; nucleotides and their derivatives; and lots of alkaloids and phospholipids declined, while most fatty acids and organic acids increased, and galloylated catechins, GA, and caffeine were almost stable. The result also suggested that approximately seven years (but not an infinite extension) was a special period for oolong tea storage, which brings about excellent taste. [ABSTRACT FROM AUTHOR]