The concept of the virtual synchronous generator (VSG) is emerging as an attractive solution for controlling the grid-connected inverter when the renewable energy has a high penetration level into ...the grid. This paper focuses on the small-signal modeling and parameters design of the power loop of the VSG, and points out that the bandwidth of the power loop should be far less than twice the line frequency for the purpose of avoiding the VSG output voltage to be severely distorted. Consequently, the line-frequency-averaged small-signal model of the VSG is derived for system analysis and parameters design. Based on the model, the decoupling conditions between the active power loops (APLs) and the reactive power loops (RPLs) of the VSG are given. Finally, a step-by-step parameters design method is proposed to facilitate the design of the control parameters of the VSG. A 10-kVA prototype is built and tested in the laboratory, and the experimental results are given to verify the effectiveness of the theoretical analysis and the proposed parameters design method.
Rationally optimizing the photoluminescence performance via accurate structural modulation is one of most important and challenging issues for hybrid halides. Herein, a viable crystal dimensional ...reduction strategy is proposed to reasonably enhance the photoluminescence quantum yield (PLQY) of hybrid antimony halide. Specifically, a synthetic technique is developed and new 1D DMPZSbCl5 ∙ H2O (DP‐SbCl5) is sliced to 0D DMPZ2SbCl6 ∙ Cl ∙ (H2O)2 (DP‐SbCl6) with crystal dimensional reduction from infinite SbCl52− chain to discrete SbCl63− octahedron. Comparing with nonluminescent 1D DP‐SbCl5, 0D DP‐SbCl6 displays highly efficient broadband yellow light emission with enhanced PLQY up to 75.94%. First‐principles calculation demonstrates that 0D DP‐SbCl6 features more flat and narrow band structure, which promotes the photoelectron localization and increases the quantum confinement, and finally boosts the luminescence efficiency. Together highly efficient and ultra‐stable luminescence performance enable DP‐SbCl6 as excellent down‐conversion broadband yellow phosphor to successfully fabricate white light emitting diodes with a high color rendering index of 92. This work provides a novel structural modulation strategy of crystal dimensional reduction to rationally optimize the PL performance of hybrid metal halides.
With controllable structural evolution from 1D to 0D hybrid antimony halides, the photoluminescence quantum yield (PLQY) realizes a notable enhancement from <1% to 75.94% in yellow spectral region benefitting from more localized photoelectrons and increased quantum confinement. This work provides a structural platform to verify the feasibility of crystal dimensionality reduction strategy to rationally improve the PLQY of metal halides.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The stem cell-based therapies for intervertebral disc degeneration have been widely studied. However, the mechanisms of mesenchymal stem cells interacting with intervertebral disc cells, such as ...nucleus pulposus cells (NPCs), remain unknown. Exosomes as a vital paracrine mechanism in cell-cell communication have been highly focused on. The purpose of this study was to detect the role of exosomes derived from bone marrow mesenchymal stem cells (BM-MSCs) and NPCs in their interaction with corresponding cells.
The exosomes secreted by BM-MSCs and NPCs were purified by differential centrifugation and identified by transmission electron microscope and immunoblot analysis of exosomal marker proteins. Fluorescence confocal microscopy was used to examine the uptake of exosomes by recipient cells. The effects of NPC exosomes on the migration and differentiation of BM-MSCs were determined by transwell migration assays and quantitative RT-PCR analysis of NPC phenotypic genes. Western blot analysis was performed to examine proteins such as aggrecan, sox-9, collagen II and hif-1α in the induced BM-MSCs. Proliferation and the gene expression profile of NPCs induced by BM-MSC exosomes were measured by Cell Counting Kit-8 and qRT-PCR analysis, respectively.
Both the NPCs and BM-MSCs secreted exosomes, and these exosomes underwent uptake by the corresponding cells. NPC-derived exosomes promoted BM-MSC migration and induced BM-MSC differentiation to a nucleus pulposus-like phenotype. BM-MSC-derived exosomes promoted NPC proliferation and healthier extracellular matrix production in the degenerate NPCs.
Our study indicates that the exosomes act as an important vehicle in information exchange between BM-MSCs and NPCs. Given a variety of functions and multiple advantages, exosomes alone or loaded with specific genes and drugs would be an appropriate option in a cell-free therapy strategy for intervertebral disc degeneration.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Development of secondary hair follicles in early postnatal cashmere goats may be adversely affected by reactive oxygen species which cause oxidative stress. Because melatonin is a potent antioxidant ...and scavenger of free radicals, this study explored the effects of melatonin on secondary hair follicle development and subsequent cashmere production. It was found that the initiation of new secondary follicles in early postnatal Inner Mongolian cashmere goats of both melatonin‐treated and control goats occurred in the first 10 weeks of age. Melatonin promoted the initiation and maturation of secondary follicles and increased their population. Importantly, the beneficial effect of melatonin on secondary follicle population remained throughout life. As a result, melatonin increased cashmere production and improved its quality in terms of reduced fiber diameter. The mechanisms underlying the role of melatonin on secondary follicle development included the enhancement of activities of antioxidant enzymes, for example, superoxide dismutase and glutathione peroxidase (GSH‐Px), elevated total antioxidant capacity, and upregulated anti‐apoptotic Bcl‐2 expression and downregulated expression of the pro‐apoptotic proteins, Bax and caspase‐3. These results reveal that melatonin serves to promote secondary hair follicle development in early postnatal cashmere goats and expands our understanding of melatonin application in cashmere production. Melatonin treatment led to an increase in both the quantity and quality of cashmere fiber. This increased the textile value of the fibers and provided economic benefit.
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DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
Plants of Artemisia annua produce artemisinin, a sesquiterpene lactone widely used in malaria treatment. Amorpha-4,11-diene synthase （ADS）, a sesquiterpene synthase, and CYP71AV1, a P450 ...monooxygenase, are two key enzymes of the artemisinin biosynthesis pathway. Accumulation of artemisinin can be induced by the phytohormone jasmonate （JA）. Here, we report the characterization of two JA-responsive AP2 family transcription factors-AaERF1 and AaERF2-from A. annua L. Both genes were highly expressed in inflorescences and strongly induced by JA. Yeast one- hybrid and electrophoretic mobility shift assay （EMSA） showed that they were able to bind to the CRTDREHVCBF2 （CBF2） and RAVlAAT （RAA） motifs present in both ADS and CYP71AV1 promoters. Transient expression of either AaERF1 or AaERF2 in tobacco induced the promoter activities of ADS or CYP71AV1, and the transgenic A. annua plants overexpressing either transcription factor showed elevated transcript levels of both ADS and CYP71AV1, resulting in increased accumulation of artemisinin and artemisinic acid. By contrast, the contents of these two metabolites were reduced in the RNAi transgenic lines in which expression of AaERF1 or AaERF2 was suppressed. These results demonstrate that AaERF1 and AaERF2 are two positive regulators of artemisinin biosynthesis and are of great value in genetic engineering of arte- misinin production.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Plant secondary metabolites play critical roles in plant-environment interactions. They are synthesized in different organs or tissues at particular developmental stages, and in response to various ...environmental stimuli, both biotic and abiotic. Accordingly, corresponding genes are regulated at the transcriptional level by multiple transcription factors. Several families of transcription factors have been identified to participate in controlling the biosynthesis and accumulation of secondary metabolites. These regulators integrate internal （often developmental） and external signals, bind to corresponding cis-elements -- which are often in the promoter regions -- to activate or repress the expression of enzyme-coding genes, and some of them interact with other transcription factors to form a complex. In this review, we summarize recent research in these areas, with an emphasis on newly-identified transcription factors and their functions in metabolism regulation.
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BFBNIB, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
Abstract
We present the first polarimetric analysis of quasiperiodic oscillations (QPOs) in a black hole binary utilizing IXPE data. Our study focuses on Swift J1727.8–1613, which experienced a ...massive outburst that was observed by various telescopes across different wavelengths. The IXPE observation we studied was conducted during the hard-intermediate state. The polarization degree (PD) and polarization angle (PA) were measured at 4.28% ± 0.20% and 1.°9 ± 1.°4, respectively. Remarkably, significant QPO signals were detected during this observation, with a QPO frequency of approximately 1.34 Hz and a fractional rms amplitude of about 12.3%. Furthermore, we conducted a phase-resolved analysis of the QPO using the Hilbert–Huang transform technique. The photon index showed a strong modulation with respect to the QPO phase. In contrast, the PD and PA exhibit no modulations in relation to the QPO phase, which is inconsistent with the expectation of the Lense–Thirring precession of the inner flow. Further theoretical studies are needed to conform with the observational results.
In this study, we successfully synthesized CsPbBr3 QDs and Mn-doped CsPbCl3 QDs, which exhibited dual-wavelength emission and achieved a high photoluminescence quantum yield (PLQY) of up to 83.4 %. ...To enhance the environmental stability of the QDs, we synthesized QDs/Polycaprolactone (PCL) composites. Using the Electrohydrodynamic (EHD) printing technique, we printed composite patterns using CsPbBr3/PCL and Mn-doped CsPbCl3/PCL. These patterns displayed dual-color fluorescence when excited at 365 nm and single-color fluorescence when excited at 410 nm. This excitation-sensitive property is due to the significant difference in emission and absorption wavelengths between CsPbBr3 QDs and Mn-doped CsPbCl3 QDs. Furthermore, we transferred the pattern onto a flexible anti-counterfeiting label using a transfer printing technology with polydimethylsiloxane (PDMS). This research represents a significant advancement in the development of CsPbX3 QDs for flexible fluorescent anti-counterfeiting applications.
CsPbBr3 and Mn-doped CsPbCl3 QDs are used to print composite patterns by EHD printing technique. The composite pattern exhibits both orange and green colors under ultraviolet light exposure, while only the green pattern is visible under blue light illumination. By encapsulating the pattern with PDMS, a flexible transparent anti-counterfeiting label is obtained. Display omitted
•Mn-doped CsPbCl3 QDs in collaboration with CsPbBr3 QDs are applied in anti-counterfeiting technology.•A fluorescence anti-counterfeiting lable is created by using EHD technology.•The label exhibits varying color information by manipulating wavelength of exciting light.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•Daily dietary intake is closely related to the occurrence of GDM.•Reportedly, prenatal exposure to air pollution could also increase the risk of GDM.•We explored interactions between diet and ...pre-pregnancy air pollution exposure.•The study was based on a prospective birth cohort in Northeast China.•The intake of animal foods could aggravate the effect of exposure to air pollution.
The prevalence of gestational diabetes mellitus (GDM) has been increasing worldwide. Dietary patterns and air pollution are closely related to the occurrence of GDM. No previous study has explored the interaction effect of air pollution exposure and dietary patterns on GDM. We explored the interaction effect between main dietary patterns and pre-pregnancy exposure to air pollution on the development of GDM based on a prospective birth cohort in Northeast China. A total of 2244 participants were included in this study. Factor analysis was used to identify dietary patterns. We found that long-term exposure to nitrogen dioxide (NO2) and carbon monoxide (CO) before pregnancy was significantly associated with an increased risk of GDM; the animal foods pattern significantly modified these associations. The sub-group analysis showed that compared with a lower intake in the animal foods pattern (NO2, odds ratio OR = 1.07, 95% confidence interval CI: 0.84, 1.35; CO, OR = 1.05, 95% CI: 0.81, 1.34), higher intake in the animal foods pattern (NO2, OR = 1.41, 95% CI: 1.09, 1.83; CO, OR = 1.36, 95% CI: 1.05, 1.76) before pregnancy increased the hazardous effects of NO2 and CO on GDM development. The intake of animal blood, animal organs, preserved eggs, and processed meat products in animal food pattern could all aggravate the effect of exposure to air pollution due to NO2 and CO on GDM. Our study demonstrated that there was a significant interaction effect between animal foods pattern and exposure to air pollution on GDM. These results provide further scientific evidence of the associations among air pollution, dietary intake, and GDM, and may help as well as the prevention of GDM.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
infection is mostly a family-based infectious disease. To facilitate its prevention and management, a national consensus meeting was held to review current evidence and propose strategies for ...population-wide and family-based
infection control and management to reduce the related disease burden.
Fifty-seven experts from 41 major universities and institutions in 20 provinces/regions of mainland China were invited to review evidence and modify statements using Delphi process and grading of recommendations assessment, development and evaluation system. The consensus level was defined as ≥80% for agreement on the proposed statements.
Experts discussed and modified the original 23 statements on family-based
infection transmission, control and management, and reached consensus on 16 statements. The final report consists of three parts: (1)
infection and transmission among family members, (2) prevention and management of
infection in children and elderly people within households, and (3) strategies for prevention and management of
infection for family members. In addition to the 'test-and-treat' and 'screen-and-treat' strategies, this consensus also introduced a novel third 'family-based
infection control and management' strategy to prevent its intrafamilial transmission and development of related diseases.
is transmissible from person to person, and among family members. A family-based
prevention and eradication strategy would be a suitable approach to prevent its intra-familial transmission and related diseases. The notion and practice would be beneficial not only for Chinese residents but also valuable as a reference for other highly infected areas.
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