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Iron antimonide (FeSb2) has been investigated for decades due to its puzzling electronic properties. It undergoes the temperature-controlled transition from an insulator to an ill-defined metal, with a cross-over from diamagnetism to paramagnetism. Extensive efforts have been made to uncover the underlying mechanism, but a consensus has yet to be reached. While macroscopic transport and magnetic measurements can be explained by different theoretical proposals, the essential spectroscopic evidence required to distinguish the physical origin is missing. In this paper, through the use of X-ray absorption spectroscopy and atomic multiplet simulations, we have observed the mixed spin states of 3d 6 configuration in FeSb2. Furthermore, we reveal that the enhancement of the conductivity, whether induced by temperature or doping, is characterized by populating the high-spin state from the low-spin state. Our work constitutes vital spectroscopic evidence that the electrical/magnetical transition in FeSb2 is directly associated with the spin-state excitation.
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DNA-dependent RNA polymerases (Pols) transfer the genetic information stored in genomic DNA to RNA in all organisms. In eukaryotes, the typical products of nuclear Pol I, Pol II, and Pol III are ribosomal RNAs, mRNAs, and transfer RNAs, respectively. Intriguingly, plants possess two additional Pols, Pol IV and Pol V, which produce small RNAs and long noncoding RNAs, respectively, mainly for silencing transposable elements. The five plant Pols share some subunits, but their distinct functions stem from unique subunits that interact with specific regulatory factors in their transcription cycles. Here, we summarize recent advances in our understanding of plant nucleus-localized Pols, including their evolution, function, structures, and transcription cycles.
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ARN Polimerasas Dirigidas por ADN , Plantas , ARN Polimerasas Dirigidas por ADN/genética , ARN Polimerasas Dirigidas por ADN/metabolismo , Plantas/genética , Plantas/metabolismo , ARN Polimerasa II/genética , ADN , Metilación de ADNRESUMEN
Animal and plant microRNAs (miRNAs) are essential for the spatio-temporal regulation of development. Together with this role, plant miRNAs have been proposed to target transposable elements (TEs) and stimulate the production of epigenetically active small interfering RNAs. This activity is evident in the plant male gamete containing structure, the male gametophyte or pollen grain. How the dual role of plant miRNAs, regulating both genes and TEs, is integrated during pollen development and which mRNAs are regulated by miRNAs in this cell type at a genome-wide scale are unknown. Here, we provide a detailed analysis of miRNA dynamics and activity during pollen development in Arabidopsis thaliana using small RNA and degradome parallel analysis of RNA end high-throughput sequencing. Furthermore, we uncover miRNAs loaded into the two main active Argonaute (AGO) proteins in the uninuclear and mature pollen grain, AGO1 and AGO5. Our results indicate that the developmental progression from microspore to mature pollen grain is characterized by a transition from miRNAs targeting developmental genes to miRNAs regulating TE activity.
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Arabidopsis/genética , Elementos Transponibles de ADN/genética , MicroARNs/genética , Polen/crecimiento & desarrollo , Polen/genética , Arabidopsis/crecimiento & desarrollo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo , Regulación de la Expresión Génica de las Plantas , Germinación/genética , MicroARNs/metabolismo , Plantas Modificadas Genéticamente , ARN de Planta/genética , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismoRESUMEN
Artemisia is a large genus encompassing about 400 diverse species, many of which have considerable medicinal and ecological value. However, complex morphological information and variation in ploidy level and nuclear DNA content have presented challenges for evolution studies of this genus. Consequently, taxonomic inconsistencies within the genus persist, hindering the utilization of such large plant resources. Researchers have utilized satellite DNAs to aid in chromosome identification, species classification, and evolutionary studies due to their significant sequence and copy number variation between species and close relatives. In the present study, the RepeatExplorer2 pipeline was utilized to identify 10 satellite DNAs from three species (Artemisia annua, Artemisia vulgaris, Artemisia viridisquama), and fluorescence in situ hybridization confirmed their distribution on chromosomes in 24 species, including 19 Artemisia species with 5 outgroup species from Ajania and Chrysanthemum. Signals of satellite DNAs exhibited substantial differences between species. We obtained one genus-specific satellite from the sequences. Additionally, molecular cytogenetic maps were constructed for Artemisia vulgaris, Artemisia leucophylla, and Artemisia viridisquama. One species (Artemisia verbenacea) showed a FISH distribution pattern suggestive of an allotriploid origin. Heteromorphic FISH signals between homologous chromosomes in Artemisia plants were observed at a high level. Additionally, the relative relationships between species were discussed by comparing ideograms. The results of the present study provide new insights into the accurate identification and taxonomy of the Artemisia genus using molecular cytological methods.
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Artemisia , Artemisia/genética , Hibridación Fluorescente in Situ , Filogenia , ADN Satélite/genética , Variaciones en el Número de Copia de ADNRESUMEN
Dynamic vision perception and processing (DVPP) is in high demand by booming edge artificial intelligence. However, existing imaging systems suffer from low efficiency or low compatibility with advanced machine vision techniques. Here, we propose a reconfigurable bipolar image sensor (RBIS) for in-sensor DVPP based on a two-dimensional WSe2/GeSe heterostructure device. Owing to the gate-tunable and reversible built-in electric field, its photoresponse shows bipolarity as being positive or negative. High-efficiency DVPP incorporating front-end RBIS and back-end CNN is then demonstrated. It shows a high recognition accuracy of over 94.9% on the derived DVS128 data set and requires much fewer neural network parameters than that without RBIS. Moreover, we demonstrate an optimized device with a vertically stacked structure and a stable nonvolatile bipolarity, which enables more efficient DVPP hardware. Our work demonstrates the potential of fabricating DVPP devices with a simple structure, high efficiency, and outputs compatible with advanced algorithms.
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BACKGROUND: Benign prostatic hyperplasia (BPH) is a prevalent disease affecting elderly men, with chronic inflammation being a critical factor in its development. Omentin-1, also known as intelectin-1 (ITLN-1), is an anti-inflammatory protein primarily found in the epithelial cells of the small intestine. This study aimed to investigate the potential of ITLN-1 in mitigating BPH by modulating local inflammation in the prostate gland. METHODS: Our investigation involved two in vivo experimental models. Firstly, ITLN-1 knockout mice (Itln-1-/-) were used to study the absence of ITLN-1 in BPH development. Secondly, a testosterone propionate (TP)-induced BPH mouse model was treated with an ITLN-1 overexpressing adenovirus. We assessed BPH severity using prostate weight index and histological analysis, including H&E staining, immunohistochemistry, and enzyme-linked immunosorbent assay. In vitro, the impact of ITLN-1 on BPH-1 cell proliferation and inflammatory response was evaluated using cell proliferation assays and enzyme-linked immunosorbent assay. RESULTS: In vivo, Itln-1-/- mice exhibited elevated prostate weight index, enlarged lumen area, and higher TNF-α levels compared to wild-type littermates. In contrast, ITLN-1 overexpression in TP-induced BPH mice resulted in reduced prostate weight index, lumen area, and TNF-α levels. In vitro studies indicated that ITLN-1 suppressed the proliferation of prostate epithelial cells and reduced TNF-α production in macrophages, suggesting a mechanism involving the inhibition of macrophage-mediated inflammation. CONCLUSION: The study demonstrates that ITLN-1 plays a significant role in inhibiting the development of BPH by reducing local inflammation in the prostate gland. These findings highlight the potential of ITLN-1 as a therapeutic target in the management of BPH.
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Proteínas Ligadas a GPI , Lectinas , Hiperplasia Prostática , Animales , Masculino , Ratones , Citocinas/genética , Citocinas/metabolismo , Proteínas Ligadas a GPI/genética , Proteínas Ligadas a GPI/metabolismo , Inflamación/patología , Lectinas/genética , Lectinas/metabolismo , Extractos Vegetales/farmacología , Próstata/metabolismo , Próstata/patología , Hiperplasia Prostática/genética , Hiperplasia Prostática/tratamiento farmacológico , Hiperplasia Prostática/metabolismo , Factor de Necrosis Tumoral alfaRESUMEN
BACKGROUND: Vascular calcification is a common vascular lesion associated with high morbidity and mortality from cardiovascular events. Antibiotics can disrupt the gut microbiota (GM) and have been shown to exacerbate or attenuate several human diseases. However, whether antibiotic-induced GM disruption affects vascular calcification remains unclear. METHODS: Antibiotic cocktail (ABX) treatment was utilized to test the potential effects of antibiotics on vascular calcification. The effects of antibiotics on GM and serum short-chain fatty acids (SCFAs) in vascular calcification mice were analyzed using 16 S rRNA gene sequencing and targeted metabolomics, respectively. Further, the effects of acetate, propionate and butyrate on vascular calcification were evaluated. Finally, the potential mechanism by which acetate inhibits osteogenic transformation of VSMCs was explored by proteomics. RESULTS: ABX and vancomycin exacerbated vascular calcification. 16 S rRNA gene sequencing and targeted metabolomics analyses showed that ABX and vancomycin treatments resulted in decreased abundance of Bacteroidetes in the fecal microbiota of the mice and decreased serum levels of SCFAs. In addition, supplementation with acetate was found to reduce calcium salt deposition in the aorta of mice and inhibit osteogenic transformation in VSMCs. Finally, using proteomics, we found that the inhibition of osteogenic transformation of VSMCs by acetate may be related to glutathione metabolism and ubiquitin-mediated proteolysis. After adding the glutathione inhibitor Buthionine sulfoximine (BSO) and the ubiquitination inhibitor MG132, we found that the inhibitory effect of acetate on VSMC osteogenic differentiation was weakened by the intervention of BSO, but MG132 had no effect. CONCLUSION: ABX exacerbates vascular calcification, possibly by depleting the abundance of Bacteroidetes and SCFAs in the intestine. Supplementation with acetate has the potential to alleviate vascular calcification, which may be an important target for future treatment of vascular calcification.
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Acetatos , Antibacterianos , Ácidos Grasos Volátiles , Microbioma Gastrointestinal , Calcificación Vascular , Animales , Microbioma Gastrointestinal/efectos de los fármacos , Calcificación Vascular/metabolismo , Calcificación Vascular/etiología , Calcificación Vascular/tratamiento farmacológico , Ratones , Ácidos Grasos Volátiles/metabolismo , Acetatos/farmacología , Antibacterianos/efectos adversos , Antibacterianos/farmacología , Masculino , Osteogénesis/efectos de los fármacos , ARN Ribosómico 16S/genética , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL , Vancomicina/efectos adversos , Vancomicina/farmacología , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/efectos de los fármacosRESUMEN
Visible-blind ultraviolet (UV) light detection has a wide application range in scenes like space environment monitoring and medical imaging. To realize miniaturized UV detectors with high performance and high integration ability, new device structures without bulky light filters need to be developed based on advanced mechanisms. Here the unipolar barrier van der Waals heterostructure (UB-vdWH) photodetector is reported that realizes filter-free visible-blind UV detection with good stability, robustness, selectivity, and high detection performance. The UB-vdWH shows a responsivity of 2452 A W-1, a photo on-off ratio of 2.94 × 105 and a detectivity of 1.26 × 1015 Jones as a UV detector, owing to the intentionally designed barrier height that suppresses dark current and photoresponse to visible light during the transport process. The good performance remains intact during 104 test cycles or even under high temperatures, which proves the stability, and robustness of the UB-vdWH, thus shows the huge potential for a wider application range.
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Trichomes, specialized hair-like structures in the epidermal cells of the aboveground parts of plants, protect plants from pests and pathogens and produce valuable metabolites. Chrysanthemum morifolium, used in tea products, has ornamental and medicinal value. However, it is susceptible to Alternaria alternata fungal infection, posing a threat to its production and use, resulting in substantial economic losses. Increasing the density of glandular trichomes enhances disease resistance and improves the production of medicinal metabolites in chrysanthemums. Jasmonate (JA), promotes the formation of glandular trichomes in various plants. However, it remains unclear whether glandular trichome in chrysanthemums are regulated by JA. Grafting, a technique to improve plant resistance to biotic stresses, has been insufficiently explored in its impact on glandular trichomes, terpenoids, and disease resistance. In this study, we demonstrated that grafting with Artemisia vulgaris rootstocks improves the resistance of chrysanthemum scions to A. alternata. Heterografted chrysanthemums exhibited higher trichome density and terpenoid content compared to self-grafted counterparts. Transcriptome analysis highlighted the significant role of CmJAZ1-like in disease resistance in heterografted chrysanthemums. Overexpressing CmJAZ1-like lines exhibited sensitivity to A. alternate, characterized by reduced glandular trichome density and limited terpenoids. Conversely, silencing lines exhibited resistance to A. alternata showcasing increased glandular trichome density and abundant terpenoids. Higher JA content was confirmed in heterografted chrysanthemum scions compared to self-grafted ones. Furthermore, we established that JA promotes the development of glandular trichomes and the synthesis of terpenoids while inducing the degradation of CmJAZ1-like proteins in chrysanthemums. These findings suggest that higher JA increases trichome density and terpenoid content, enhancing resistance to A. alternata by regulating CmJAZ1-like in heterografted chrysanthemums.
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Here, we combined magnetometry, multi-frequency electronic paramagnetic resonance, and wave function based ab initio calculations to investigate magnetic properties of two high spin Co(II) complexes Co(BDPRP) (BDPRP=2,6-bis((2-(S)-di(4-R)phenylhydroxylmethyl-1-pyrrolidi-nyl)methyl)pyridine, R=H for 8; R=tBu for 9). Complexesâ 8 and 9 featuring effective D3h symmetry were found to possess D=24.0 and 32.0â cm-1, respectively, in their S=3/2 ground states of 1 e ' ' d x z / y z 4 1 e ' d x y / x 2 - y 2 2 1 a 1 ' d z 2 1 ${{\left(1{{\rm e}}^{{\rm { {^\prime}}}{\rm { {^\prime}}}}\right({d}_{xz/yz}\left)\right)}^{4}{\left(1{{\rm e}}^{{\rm { {^\prime}}}}\right({d}_{{xy/{x}^{2}-y}^{2}}\left)\right)}^{2}{\left(1{{\rm a}}_{1}^{{\rm { {^\prime}}}}\right({d}_{{z}^{2}}\left)\right)}^{1}}$ . Ligand field analyses revealed that the low-lying d-d excited states make either positive or vanishing contributions to D. Hence, total positive D values were measured for 8 and 9, as well as related D3h high spin Co(II) complexes. In contrast, negative D values are usually observed for C3v congeners. In-depth analyses suggested that lowering symmetry from D3h to C3v induces orbital mixing between 1 e d x z / y z ${1{\rm e}\left({d}_{xz/yz}\right)}$ and 2 e d x y / x 2 - y 2 ${2{\rm e}\left({d}_{{xy/{x}^{2}-y}^{2}}\right)}$ and admixes excited state 4 A 2 1 e â 2 e ${{}^{4}{{\rm A}}_{2}\left(1e\to 2e\right)}$ into the ground state. Both factors turn the total D value progressively negative with the increasing distance (δ) of the Co(II) center out of the equatorial plane. Therefore, δ determines the sign and magnitude of final D values of five-coordinate trigonal bipyramidal S=3/2 Co(II) complexes as measured for a series of such species with varying δ.
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Benign prostatic hyperplasia (BPH) is a multifactorial disease in which abnormal growth factor activation and embryonic reawakening are considered important factors. Here we demonstrated that the aberrant activation of transforming growth factor ß (TGF-ß)/Rho kinase 1 (ROCK1) increased the stemness of BPH tissue by recruiting mesenchymal stem cells (MSCs), indicating the important role of embryonic reawakening in BPH. When TGF-ß/ROCK1 is abnormally activated, MSCs are recruited and differentiate into fibroblasts/myofibroblasts, leading to prostate stromal hyperplasia. Further research showed that inhibition of ROCK1 activation suppressed MSC migration and their potential for stromal differentiation. Collectively, our findings suggest that abnormal activation of TGF-ß/ROCK1 regulates stem cell lineage specificity, and the small molecule inhibitor GSK269962A could target ROCK1 and may be a potential treatment for BPH.
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Células Madre Mesenquimatosas , Hiperplasia Prostática , Factor de Crecimiento Transformador beta , Quinasas Asociadas a rho , Quinasas Asociadas a rho/metabolismo , Masculino , Hiperplasia Prostática/patología , Hiperplasia Prostática/metabolismo , Humanos , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/patología , Factor de Crecimiento Transformador beta/metabolismo , Animales , Diferenciación Celular , Próstata/patología , Próstata/metabolismo , Movimiento Celular , Ratones , Células del Estroma/metabolismo , Células del Estroma/patologíaRESUMEN
Neurodegenerative diseases (NDDs) such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis epitomize a class of insidious and relentless neurological conditions that are difficult to cure. Conventional therapeutic regimens often fail due to the late onset of symptoms, which occurs well after irreversible neurodegeneration has begun. The integrity of the blood-brain barrier (BBB) further impedes efficacious drug delivery to the central nervous system, presenting a formidable challenge in the pharmacological treatment of NDDs. Recent scientific inquiries have shifted focus toward the peripheral biological systems, investigating their influence on central neuropathology through the lens of extracellular vesicles (EVs). These vesicles, distinguished by their ability to breach the BBB, are emerging as dual operatives in the context of NDDs, both as conveyors of pathogenic entities and as prospective vectors for therapeutic agents. This review critically summarizes the burgeoning evidence on the role of extracerebral EVs, particularly those originating from bone, adipose tissue, and gut microbiota, in modulating brain pathophysiology. It underscores the duplicity potential of peripheral EVs as modulators of disease progression and suggests their potential as novel vehicles for targeted therapeutic delivery, positing a transformative impact on the future landscape of NDD treatment strategies. Search strategy A comprehensive literature search was conducted using PubMed, Web of Science, and Scopus from January 2000 to December 2023. The search combined the following terms using Boolean operators: "neurodegenerative disease" OR "Alzheimer's disease" OR "Parkinson's disease" OR "Amyotrophic lateral sclerosis" AND "extracellular vesicles" OR "exosomes" OR "outer membrane vesicles" AND "drug delivery systems" AND "blood-brain barrier". MeSH terms were employed when searching PubMed to refine the results. Studies were included if they were published in English, involved human subjects, and focused on the peripheral origins of EVs, specifically from bone, adipose tissue, and gut microbiota, and their association with related diseases such as osteoporosis, metabolic syndrome, and gut dysbiosis. Articles were excluded if they did not address the role of EVs in the context of NDDs or did not discuss therapeutic applications. The titles and abstracts of retrieved articles were screened using a dual-review process to ensure relevance and accuracy. The reference lists of selected articles were also examined to identify additional relevant studies.
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Enfermedad de Alzheimer , Exosomas , Vesículas Extracelulares , Enfermedad de Parkinson , Humanos , Estudios ProspectivosRESUMEN
BACKGROUND: Bone marrow mesenchymal stem cells (BMSCs) can undergo inadequate osteogenesis or excessive adipogenesis as they age due to changes in the bone microenvironment, ultimately resulting in decreased bone density and elevated risk of fractures in senile osteoporosis. This study aims to investigate the effects of osteocyte senescence on the bone microenvironment and its influence on BMSCs during aging. RESULTS: Primary osteocytes were isolated from 2-month-old and 16-month-old mice to obtain young osteocyte-derived extracellular vesicles (YO-EVs) and senescent osteocyte-derived EVs (SO-EVs), respectively. YO-EVs were found to significantly increase alkaline phosphatase activity, mineralization deposition, and the expression of osteogenesis-related genes in BMSCs, while SO-EVs promoted BMSC adipogenesis. Neither YO-EVs nor SO-EVs exerted an effect on the osteoclastogenesis of primary macrophages/monocytes. Our constructed transgenic mice, designed to trace osteocyte-derived EV distribution, revealed abundant osteocyte-derived EVs embedded in the bone matrix. Moreover, mature osteoclasts were found to release osteocyte-derived EVs from bone slices, playing a pivotal role in regulating the functions of the surrounding culture medium. Following intravenous injection into young and elderly mouse models, YO-EVs demonstrated a significant enhancement of bone mass and biomechanical strength compared to SO-EVs. Immunostaining of bone sections revealed that YO-EV treatment augmented the number of osteoblasts on the bone surface, while SO-EV treatment promoted adipocyte formation in the bone marrow. Proteomics analysis of YO-EVs and SO-EVs showed that tropomyosin-1 (TPM1) was enriched in YO-EVs, which increased the matrix stiffness of BMSCs, consequently promoting osteogenesis. Specifically, the siRNA-mediated depletion of Tpm1 eliminated pro-osteogenic activity of YO-EVs both in vitro and in vivo. CONCLUSIONS: Our findings suggested that YO-EVs played a crucial role in maintaining the balance between bone resorption and formation, and their pro-osteogenic activity declining with aging. Therefore, YO-EVs and the delivered TPM1 hold potential as therapeutic targets for senile osteoporosis.
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Vesículas Extracelulares , Células Madre Mesenquimatosas , Osteocitos , Osteogénesis , Tropomiosina , Animales , Masculino , Ratones , Adipogénesis , Diferenciación Celular , Células Cultivadas , Vesículas Extracelulares/metabolismo , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/citología , Ratones Endogámicos C57BL , Ratones Transgénicos , Osteoclastos/metabolismo , Osteocitos/metabolismo , Osteoporosis/metabolismo , Tropomiosina/metabolismo , Tropomiosina/genéticaRESUMEN
The attention hypothesis, which assumes that font emphasis captures readers' attention, is usually used to explain the mechanism by which such emphasis operates. This study further delineates the attention hypothesis by investigating the ways in which font emphasis captures attention and its effects on the integration of emphasized information into the previous context. We computed event-related potentials and frequency band-specific electroencephalographic power changes occurring while participants read sentences containing critical words that were either emphasized (i.e., displayed in a color different from the other words in the sentence) or not (i.e., shown in the same color as the rest of the sentence) and semantically congruent with prior words or not. The results showed that the emphasized words (as compared to control words) elicited a reduced N1 and increased P2, indicating that font emphasis reduced familiarity-based visuo-orthographic processing and instead increased controlled attentional processing. We also observed greater P300 and power decreases in the alpha and beta frequency range in response to critical words in the emphasized condition, suggesting that font emphasis enhances focal attention to promote a fuller integration of information into the sentence context. Furthermore, relative to the control condition, the emphasized condition induced delta and theta power increases for the incongruent words. These results suggest that font emphasis increases the efficiency of glyph processing, which facilitates lexical access.
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Comprensión , Lectura , Humanos , Comprensión/fisiología , Semántica , Potenciales Evocados/fisiología , Electroencefalografía/métodosRESUMEN
Despite multiple investigations assessing the impact of phytosterol supplementation on serum lipid levels, there is still a great deal of debate regarding the benefits of this intervention in the management of dyslipidemia. Therefore, we aimed at clarifying this dilemma by conducting the present umbrella review of interventional meta-analyses. Scopus, PubMed, Web of Science, and EMBASE were used to search for pertinent publications on the effect of phytosterol supplementation on the lipid profile in humans up to June 2023. To compute the overall effect size (ES) and confidence intervals (CI), the random-effects model was used. The I2 statistic and Cochrane's Q-test were applied to estimate the heterogeneity among the studies. Seventeen meta-analyses with 23 study arms were included in the umbrella meta-analysis. Data pooled from the 23 eligible arms revealed that phytosterol supplementation reduces low-density lipoprotein cholesterol (LDL-C) (ES = -11.47 mg/dL; 95% CI: -12.76, -10.17, p < 0.001), total cholesterol (TC) (ES = -13.02 mg/dL; 95% CI: -15.68, -10.37, p < 0.001), and triglyceride (TG) (ES = -3.77 mg/dL; 95% CI: -6.04, -1.51, p = 0.001). Subgroup analyses showed that phytosterol administration with dosage ≥2 g/day and duration over 8 weeks and in hypercholesterolemic subjects was more likely to decrease LDL-C, TC, and TG. Phytosterol administration did not significantly modify HDL-C (ES = 0.18 mg/dL; 95% CI: -0.13, -0.51, p = 258) levels when compared to controls. The present umbrella meta-analysis confirms that phytosterol administration significantly reduces LDL-C, TC, and TG, with a greater effect with doses of ≥2 g/day and treatment duration >8 weeks, suggesting its possible application as a complementary therapy for cardiovascular risk reduction. Further studies are needed to determine the efficacy of phytosterols in patients with specific health conditions, as well as to ascertain the adverse effects, the maximum tolerable dose, and the maximum recommended duration of phytosterol administration.
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Fitosteroles , Humanos , Fitosteroles/farmacología , LDL-Colesterol , HDL-Colesterol , Triglicéridos , Suplementos DietéticosRESUMEN
In-sensor computing hardware based on emerging reconfigurable photosensors can effectively reduce redundant data and decrease power consumption, which can greatly promote the evolution of machine vision. However, because of the complex device structures and low integration abilities, the common architectures mainly lie in two dimensions, resulting in low time and area efficiencies. Here we propose a three-dimensional (3D) neuromorphic photosensor array for parallel in-sensor image processing. It is constructed on a vertical Graphite/CuInP2S6/Graphite photosensor unit, where the directional Cu+ ion migrations after voltage pulse programming enable a reconfigurable photovoltaic effect and an in-sensor computing capability. With a memristor-like device structure, van der Waals interfaces, and a high uniformity with a low crosstalk problem, a 10 × 10 array is fabricated for intelligent image recognition. Furthermore, using a vertically stacked 3D 3 × 3 × 3 array, we demonstrate an in-sensor convolution strategy with high time and area efficiencies.
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Heterogeneous electrocatalysis closely relies on the electronic structure of the catalytic materials. The ferroelectric-to-paraelectric phase transition of the materials also involves a change in the state of electrons that could impact the electrocatalytic activity, but such correlation remains unexplored. Here, we demonstrate experimentally and theoretically that the intrinsic electrocatalytic activity could be regulated as exampled by hydrogen evolution reaction catalysis over two-dimensional ferroelectric CuInP2S6. The obvious discontinuity in the overpotential and apparent activation energy values for CuInP2S6 electrode are illustrated during the ferroelectric-to-paraelectric phase transition caused by copper displacement around Tc point (318â K), revealing the ferroelectro-catalytic effect on thermodynamics and kinetics of electrocatalysis. When loading Pt single atom on the CuInP2S6, the paraelectric phase one showed an improved hydrogen evolution activity with smaller apparent activation energy over the ferroelectric phase counterpart. This is attributed to the copper hopping between two sulfur planes, which alternate between strong and weak H adsorption at the Pt sites to simultaneously promote H+ reactant adsorption and H2 product desorption.
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Polyethylene oxide (PEO) based polymer electrolytes show promise in expanding the practical applications of lithium (Li) batteries. However, their applications in Li batteries are usually restricted owing to the lack of mechanical strength, poor oxidative stability, and relatively large thickness. Herein, a nanofibrous polyimide (PI) framework enhanced plasticized-PEO solid electrolyte is prepared to realize good mechanical and electrochemical performances. Following the configuration with the PI matrix, this "polymer in polymer" composite electrolyte with a thickness of 17.5 µm exhibits enhanced mechanical strength (13.9 MPa) and outstanding thermal stability. Additionally, it preserves the high ionic conductivity (2.25 × 10-4 S cm-1 , 25 °C). The Li||Li symmetrical battery with the modified electrolyte could achieve a steady Li plating/stripping of more than 500 h, and the critical current density reaches up to 0.6 mA cm-2 at ambient temperature. The LiFePO4 batteries delivery favorable capacity of 132.2 mAh g-1 with capacity retentions of 96.4% and 85.9% after 500 and 1000 cycles at 1 C, respectively. Acceptable cycling performance also could be achieved in LiNi0.5 Co0. 2 Mn0. 3 O2 solid batteries via an inorganic-rich artificial cathode electrolyte interphase.
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Metallic-phase iron sulfide (e.g., Fe7 S8 ) is a promising candidate for high power density sodium storage anode due to the inherent metal electronic conductivity and unhindered sodium-ion diffusion kinetics. Nevertheless, long-cycle stability can not be achieved simultaneously while designing a fast-charging Fe7 S8 -based anode. Herein, Fe7 S8 encapsulated in carbon-sulfur bonds doped hollow carbon fibers (NHCFs-S-Fe7 S8 ) is designed and synthesized for sodium-ion storage. The NHCFs-S-Fe7 S8 including metallic-phase Fe7 S8 embrace higher electron specific conductivity, electrochemical reversibility, and fast sodium-ion diffusion. Moreover, the carbonaceous fibers with polar CSFe bonds of NHCFs-S-Fe7 S8 exhibit a fixed confinement effect for electrochemical conversion intermediates contributing to long cycle life. In conclusion, combined with theoretical study and experimental analysis, the multinomial optimized NHCFs-S-Fe7 S8 is demonstrated to integrate a suitable structure for higher capacity, fast charging, and longer cycle life. The full cell shows a power density of 1639.6 W kg-1 and an energy density of 204.5 Wh kg-1 , respectively, over 120 long cycles of stability at 1.1 A g-1 . The underlying mechanism of metal sulfide structure engineering is revealed by in-depth analysis, which provides constructive guidance for designing the next generation of durable high-power density sodium storage anodes.
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Iron oxyhydroxide has been considered an auspicious electrocatalyst for the oxygen evolution reaction (OER) in alkaline water electrolysis due to its suitable electronic structure and abundant reserves. However, Fe-based materials seriously suffer from the tradeoff between activity and stability at a high current density above 100 mA cm-2 . In this work, the Ce atom is introduced into the amorphous iron oxyhydroxide (i.e., CeFeOx Hy ) nanosheet to simultaneously improve the intrinsic electrocatalytic activity and stability for OER through regulating the redox property of iron oxyhydroxide. In particular, the Ce substitution leads to the distorted octahedral crystal structure of CeFeOx Hy , along with a regulated coordination site. The CeFeOx Hy electrode exhibits a low overpotential of 250 mV at 100 mA cm-2 with a small Tafel slope of 35.1 mVdec-1 . Moreover, the CeFeOx Hy electrode can continuously work for 300 h at 100 mA cm-2 . When applying the CeFeOx Hy nanosheet electrode as the anode and coupling it with the platinum mesh cathode, the cell voltage for overall water splitting can be lowered to 1.47 V at 10 mA cm-2 . This work offers a design strategy for highly active, low-cost, and durable material through interfacing high valent metals with earth-abundant oxides/hydroxides.