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Basal cells (BCs) are the progenitor cells responsible for tracheal epithelium integrity. Here, we demonstrate that mitochondrial pyruvate carriers (MPCs) act as metabolic checkpoints that are essential for BC fate decision. Inhibition of MPCs enables long-term expansion of BCs from both mice and humans. Genetic inactivation of Mpc2 in mice leads to BC hyperplasia and reduced ciliated cells during homeostasis, as well as delayed epithelial regeneration and accumulation of intermediate cells following injury. Mechanistically, MPC2 links glycolysis to ATP citrate lyase (ACLY)-dependent cytosolic acetyl-coenzyme A (CoA) generation, which is required for the epigenetic control of differentiation-related gene transcription. Modulating this metabolic-epigenetic axis partially rescues Yes-associated protein (YAP)-dysfunction-induced changes in BCs. Importantly, exogenous citrate promotes the differentiation of BCs from chronic obstructive lung disease (COPD) patients. Thus, beyond demonstrating the role of pyruvate metabolism in BC fate decision, our study suggests that targeting pyruvate-citrate metabolism may serve as a potential strategy to rectify abnormal BC behavior in lung diseases.
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Escherichia coli MnmE and MnmG form a complex (EcMnmEG), generating transfer RNA (tRNA) 5-carboxymethylaminomethyluridine (cmnm5U) modification. Both cmnm5U and equivalent 5-taurinomethyluridine (τm5U, catalyzed by homologous GTPBP3 and MTO1) are found at U34 in several human mitochondrial tRNAs (hmtRNAs). Certain mitochondrial DNA (mtDNA) mutations, including m.3243A > G in tRNALeu(UUR) and m.8344A > G in tRNALys, cause genetic diseases, partially due to τm5U hypomodification. However, whether other mtDNA variants in different tRNAs cause a defect in τm5U biogenesis remains unknown. Here, we purified naturally assembled EcMnmEG from E. coli. Notably, EcMnmEG was able to incorporate both cmnm5U and τm5U into hmtRNATrp (encoded by MT-TW), providing a valuable basis for directly monitoring the effects of mtDNA mutations on U34 modification. In vitro, several clinical hmtRNATrp pathogenic mutations caused U34 hypomodification. A patient harboring an m.5541C > T mutation exhibited hmtRNATrp τm5U hypomodification. Moreover, using mtDNA base editing, we constructed two cell lines carrying m.5532G > A or m.5545C > T mutations, both of which exhibited hmtRNATrp τm5U hypomodification. Taurine supplementation improved mitochondrial translation in patient cells. Our findings describe the third hmtRNA species with mutation-related τm5U-hypomodification and provide new insights into the pathogenesis and intervention strategy for hmtRNATrp-related genetic diseases.
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The generation of cold molecules is an important topic in the field of cold atoms and molecules and has received relevant advanced research attention in ultracold chemistry, quantum computation, and quantum metrology. With a high atomic phase space density, optical dipole traps have been widely used to prepare, trap, and study cold molecules. In this work, Rb2 molecules were photoassociated in a magneto-optical trap to obtain a precise rovibrational spectrum, which provided accurate numerical references for the realization of multiple frequency photoassociation. By meeting the harsh requirements of photoassociation in optical dipole traps, the cold molecule photoassociation process was well explored, and different photoassociation resonances were simultaneously addressed in a single optical dipole trap. This method can be universally extended to simultaneously photoassociate cold molecules with different internal states or atomic species in a single optical dipole trap, thus advancing generous cold molecule studies such as cold molecule collision dynamics.
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Erythroderma, an inflammatory skin condition characterized by widespread erythema with variable degrees of exfoliation, pustulation, or vesiculobullous formation, is associated with high morbidity and mortality. Determining the underlying cause of erythroderma frequently presents a diagnostic challenge, which may contribute to the condition's relatively poor prognosis. This review covers the clinical presentation, pathophysiology, diagnosis, and treatment of erythroderma. It discusses similarities and differences among the many underlying etiologies of the condition and differences between erythrodermic and non-erythrodermic presentations of the same dermatosis. Finally, this article explores current research that may provide future tools in the diagnosis and management of erythroderma.
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Dermatitis Exfoliativa , Humanos , Dermatitis Exfoliativa/diagnóstico , Dermatitis Exfoliativa/etiología , Dermatitis Exfoliativa/terapia , Adulto , Diagnóstico Diferencial , Piel/patología , PronósticoRESUMEN
Two prevalent ecological mechanisms, niche dimensionality and light asymmetry, may well explain species loss with fertilization gradients in grassland communities. Although there is still controversy surrounding the two competitive mechanisms that maintain species coexistence, few studies have examined the patterns of change in dissimilarity in species composition (ß-diversity) and the relative explanatory contributions of plant functional traits to α- and ß-diversity when multiple resources are added. To clarify this knowledge gap, we conducted a 6-year experiment of resource addition in an alpine meadow on the Qinghai-Tibet Plateau to assess how species richness and spatial ß-diversity are affected by increasing numbers of added resources (NAR) and light limitation. Our results found that both NAR and light limitation led to decreased species richness, suggesting that niche dimensionality and light asymmetry may contribute equally to species loss, rather than either alone. Moreover, NAR is the primary factor responsible for the increase in ß-diversity, which exhibits a negative relationship with species richness. Furthermore, the increase in height is the most likely explanation for ß-diversity, while the increase in SLA is the most likely explanation for species richness, thereby indicating the changes in species richness and composition can be effectively explained by the response of certain morphological functional traits with the addition of multiple resources. Future research should focus on the complex interactions of different ecological mechanisms that contribute to the maintenance of biodiversity in grassland ecosystems all over the world.
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Tumor tissues exhibit a complex spatial architecture within the tumor microenvironment (TME). Spatially resolved transcriptomics (SRT) is promising for unveiling the spatial structures of the TME at both cellular and molecular levels, but identifying pathology-relevant spatial domains remains challenging. Here, we introduce SpaTopic, a statistical learning framework that harmonizes spot clustering and cell-type deconvolution by integrating single-cell transcriptomics and SRT data. Through topic modeling, SpaTopic stratifies the TME into spatial domains with coherent cellular organization, facilitating refined annotation of the spatial architecture with improved performance. We assess SpaTopic across various tumor types and show accurate prediction of tertiary lymphoid structures and tumor boundaries. Moreover, marker genes derived from SpaTopic are transferrable and can be applied to mark spatial domains in other datasets. In addition, SpaTopic enables quantitative comparison and functional characterization of spatial domains across SRT datasets. Overall, SpaTopic presents an innovative analytical framework for exploring, comparing, and interpreting tumor SRT data.
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Neoplasias , Transcriptoma , Microambiente Tumoral , Humanos , Microambiente Tumoral/genética , Neoplasias/genética , Neoplasias/patología , Perfilación de la Expresión Génica/métodos , Aprendizaje Automático , Regulación Neoplásica de la Expresión Génica , Análisis de la Célula Individual/métodosRESUMEN
Photoperiod can regulate the broodiness of geese and thus increase their egg-laying rate. The laying performance of geese is mainly determined by ovary and follicle development. To understand the effect of photoperiod on the ovary and small white follicles, sixteen 220-day-old healthy female Zhedong white geese were randomly divided into two groups for long photoperiods (15L:9D) and short photoperiods (9L:15D). The geese were euthanized after two months of feeding, and their ovaries and follicles were collected for transcriptome sequencing. RNA-seq analysis identified 187 and 448 differentially expressed genes in ovaries and small white follicles of different photoperiod groups, respectively. A long photoperiod promotes high expression of SPP1, C6, MZB1, GP1BA, and FCGBP genes in the ovaries, and increases the expression of SPP1, ANGPTL5, ALPL, ZP1, and CHRNA4 genes in small white follicles. Functional enrichment analysis showed that photoperiod could affect respiratory system development, smooth muscle cell proliferation in ovaries, and extracellular matrix-related function in small white follicles. WGCNA revealed 31 gene modules, of which 2 were significantly associated with ovarian weight and 17 with the number of small white follicles. Our results provide a better understanding of the molecular regulation in the photoperiod affecting goose reproduction.
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Plants NADP-malic enzymes (NADP-MEs) act as a class of oxidative decarboxylase to mediate malic acid metabolism in organisms. Despite NADP-MEs have been demonstrated to play pivotal roles in regulating diverse biological processes, the role of NADP-MEs involving in plant growth and development remains rarely known. Here, we characterized the function of rice cytosolic OsNADP-ME2 in regulating plant height. The results showed that RNAi silencing and knock-out of OsNADP-ME2 in rice results in a dwarf plant structure, associating with significant expression inhibition of genes involving in phytohormone Gibberellin (GA) biosynthesis and signaling transduction, but with up-regulation for the expression of GA signaling suppressor SLR1. The accumulation of major bioactive GA1, GA4 and GA7 are evidently altered in RNAi lines, and exogenous GA treatment compromises the dwarf phenotype of OsNADP-ME2 RNAi lines. RNAi silencing of OsNADP-ME2 also causes the reduction of NADP-ME activity associating with decreased production of pyruvate. Thus, our data revealed a novel function of plant NADP-MEs in modulation of rice plant height through regulating bioactive GAs accumulation and GA signaling, and provided a valuable gene resource for rice plant architecture improvement.
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Objective: Asparagine synthetase (ASNS) is an aminotransferase responsible for the biosynthesis of aspartate by using aspartic acid and glutamine. ASNS is highly expressed in fast-growing broilers, but few studies have reported the regulatory role of ASNS in muscle development. Methods: To explore the function of ASNS in chicken muscle development, the expression of ASNS in different chicken breeds and tissues were first performed by real-time quantitative reverse transcription polymerase chain reaction (RT-PCR). Then, using real-time quantitative RT-PCR, western blot, EdU assay, cell cycle assay and immunofluorescence, the effects of ASNS on the proliferation and differentiation of chicken skeletal muscle satellite cell (SMSC) were investigated. Finally, potential mechanisms by which ASNS influences chicken muscle fiber differentiation were identified through RNA-Seq. Results: The mRNA expression pattern of ASNS in muscles mirrors trends in muscle fiber cross-sectional area, average daily weight gain, and muscle weight across different breeds. ASNS knockdown inhibited SMSC proliferation, while overexpression showed the opposite. Moreover, ASNS attenuated SMSC differentiation by activating the Adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) pathway. Additionally, 5-aminoimidazole-4-carboxamide1-ß-D-ribofuranoside (AICAR) treatment suppressed the cell differentiation induced by siRNA-ASNS. RNA-Seq identified 1968 differentially expressed genes (DEGs) during chicken SMSC differentiation when overexpression ASNS. Gene Ontology (GO) enrichment analysis revealed that these DEGs primarily participated in 8 biological processes, 8 cellular components, and 4 molecular functions. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis identified several significantly enriched signaling pathways, such as the JAK-STAT signaling pathway, TNF signaling pathway, Toll-like receptor signaling pathway, and PI3K-Akt signaling pathway. Conclusion: ASNS promotes proliferation while inhibits the differentiation of chicken skeletal muscle satellite cells. This study provides a theoretical basis for studying the role of ASNS in muscle development.
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Silty soil was widely used as filling soil materials for the replacement of expansive soil in cold regions. This paper presents a straightforward approach for the effects of wetting-drying-freezing-thawing cycles on mechanical behaviors of silty soil and expansive soil by laboratory tests. The results showed that the silty soil and expansive soil after 7th wetting-drying-freezing-thawing cycles presented the decreases of elastic modulus, failure strength, cohesion and angel of internal friction by 8.9 %â¼12.0 %, 7.7 %â¼9.0 %, 7.9 %, 4.5 % and 17.6 %â¼37.0 %, 20.5 %â¼29.4 %, 43.2 %, 13.0 %, respectively, indicating that wetting-drying-freezing-thawing cycles had little impact on mechanical property of silty soil and a great influence on that of expansive soil. Among them, the mechanical property attenuation ratio in the first three wetting-drying-freezing-thawing cycles accounted for over 90 % of the total. In the meantime, the micro-structure damage, surface crack characteristics and grain size distribution variations of expansive soil were all more significantly than these of silty soil exposed to wetting-drying-freezing-thawing cycles, which brought insight into the causes of the differences in mechanical properties for silty soil and expansive soil. It is found that the silty soil properties were more stable than expansive soil properties, and the silty soil is very effective for replacing the expansive soil below canal structures in cold regions.
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It is very crucial to investigate key molecules that are involved in myelination to gain an understanding of brain development and injury. We have reported for the first time that pathogenic variants p.R477H and p.P505S in KARS, which encodes lysyl-tRNA synthetase (LysRS), cause leukoencephalopathy with progressive cognitive impairment in humans. The role and action mechanisms of KARS in brain myelination during development are unknown. Here, we first generated Kars knock-in mouse models through the CRISPR-Cas9 system. Kars knock-in mice displayed significant cognitive deficits. These mice also showed significantly reduced myelin density and content, as well as significantly decreased myelin thickness during development. In addition, Kars mutations significantly induced oligodendrocyte differentiation arrest and reduction in the brain white matter of mice. Mechanically, oligodendrocytes' significantly imbalanced expression of differentiation regulators and increased capase-3-mediated apoptosis were observed in the brain white matter of Kars knock-in mice. Furthermore, Kars mutations significantly reduced the aminoacylation and steady-state level of mitochondrial tRNALys and decreased the protein expression of subunits of oxidative phosphorylation complexes in the brain white matter. Kars knock-in mice showed decreased activity of complex IV and significantly reduced ATP production and increased reactive oxygen species in the brain white matter. Significantly increased percentages of abnormal mitochondria and mitochondrion area were observed in the oligodendrocytes of Kars knock-in mouse brain. Finally, melatonin (a mitochondrion protectant) significantly attenuated mitochondrion and oligodendrocyte deficiency in the brain white matter of KarsR504H/P532S mice. The mice treated with melatonin also showed significantly restored myelination and cognitive function. Our study first establishes Kars knock-in mammal models of leukoencephalopathy and cognitive impairment and indicates important roles of KARS in the regulation of mitochondria, oligodendrocyte differentiation and survival, and myelination during brain development and application prospects of melatonin in KARS (or even aaRS)-related diseases.
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Lisina-ARNt Ligasa , Melatonina , Vaina de Mielina , Oligodendroglía , Animales , Ratones , Aminoacil-ARNt Sintetasas/genética , Aminoacil-ARNt Sintetasas/metabolismo , Encéfalo/metabolismo , Encéfalo/patología , Técnicas de Sustitución del Gen , Leucoencefalopatías/genética , Leucoencefalopatías/metabolismo , Leucoencefalopatías/patología , Melatonina/metabolismo , Mutación , Vaina de Mielina/metabolismo , Oligodendroglía/metabolismo , Lisina-ARNt Ligasa/genéticaRESUMEN
Unsupervised semantic segmentation is important for understanding that each pixel belongs to known categories without annotation. Recent studies have demonstrated promising outcomes by employing a vision transformer backbone pre-trained on an image-level dataset in a self-supervised manner. However, those methods always depend on complex architectures or meticulously designed inputs. Naturally, we are attempting to explore the investment with a straightforward approach. To prevent over-complication, we introduce a simple Dense Embedding Contrast network (DECNet) for unsupervised semantic segmentation in this paper. Specifically, we propose a Nearest Neighbor Similarity strategy (NNS) to establish well-defined positive and negative pairs for dense contrastive learning. Meanwhile, we optimize a contrastive objective named Ortho-InfoNCE to alleviate the false negative problem inherent in contrastive learning for further enhancing dense representations. Finally, extensive experiments conducted on COCO-Stuff and Cityscapes datasets demonstrate that our approach outperforms state-of-the-art methods.
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Redes Neurales de la Computación , Semántica , Aprendizaje Automático no Supervisado , Algoritmos , Humanos , Procesamiento de Imagen Asistido por Computador/métodosRESUMEN
In today's energy landscape, the rise of energy crises spurred by rapid industrial expansion demands the development of advanced energy storage systems, especially those leveraging renewable sources independently. Pseudocapacitors, renowned for their high specific capacitance (C s), offer a promising solution. Among them, transition metal nitride-based oxides stand out because of their remarkable conductivity and storage capacity, making them ideal candidates for supercapacitor (SC) cathode materials. In a recent study, we employed a wet-chemical method to synthesize a TiN-ZnO composite, showing potential as an electrode material for supercapacitor systems. The resulting composite exhibited promising crystallinity, indicating its suitability for electrode applications. Impressively, the TiN-ZnO electrode demonstrated a specific capacitance (C s) of 469 F g-1 during electrochemical testing. Additionally, it showcased a high energy density (E d) of 19.83 W h kg-1 and a power density (P d) of 6298.2 W kg-1. Moreover, it displayed exceptional cycling stability, retaining 95% of its performance over 7500 cycles. With superior electrochemical properties compared to pure materials, the fabricated TiN-ZnO electrode holds significant promise for supercapacitors and other energy-related technologies. This advancement presents a compelling solution to the urgent need for efficient and sustainable energy storage in the modern era.
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Transfer RNAs (tRNAs) play central roles in protein biosynthesis. Post-transcriptional RNA modifications affect tRNA function and stability. Among these modifications, RNA editing is a widespread RNA modification in three domains of life. Proteins of the adenosine deaminase acting on tRNA (ADAT) family were discovered more than 20â years ago. They catalyze the deamination of adenosine to inosine (A-to-I) or cytidine to uridine (C-to-U) during tRNA maturation. The most studied example is the TadA- or ADAT2/3-mediated A-to-I conversion of the tRNA wobble position in the anticodon of prokaryotic or eukaryotic tRNAs, respectively. This review provides detailed information on A-to-I and C-to-U editing of tRNAs in different domains of life, presents recent new findings on ADATs for DNA editing, and finally comments on the association of mutations in the ADAT3 gene with intellectual disability.
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In this paper, the stability, mechanical properties and electronic structure of carbides in steel were calculated using the first-principles method based on the density functional theory (DFT). Firstly, the MC, M2C, M6C (M = Cr, Mo, V, Fe) carbides models were established. Then, different interphases' lattice constants, formation enthalpy, binding energy and elastic modulus were calculated. The stability, hardness, ductility and anisotropy of each phase were finally analyzed. The results show that these phases are stable, and the stability is closely related to the electron loss ability of its metal elements. The stronger the electron loss ability of its metal elements, the more stable the formed phase. As for MC carbides, MoC has the largest bulk modulus and hardness. As for M2C carbides, the Poisson's ratio of Cr2C is the smallest, and all phases except for Cr2C show toughness and ductility. The anisotropy of M6C carbides is relatively poor.
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Comparison of the 2007 EORTC/ISCL and the 2022 EORTC/ISCL/USCLC blood staging guidelines for cutaneous T-cell lymphoma at a single institution reveals the newer guidelines fail to detect a subset of patients with Sézary syndrome with low blood burden.
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Linfoma Cutáneo de Células T , Estadificación de Neoplasias , Síndrome de Sézary , Neoplasias Cutáneas , Humanos , Síndrome de Sézary/patología , Síndrome de Sézary/diagnóstico , Síndrome de Sézary/sangre , Linfoma Cutáneo de Células T/diagnóstico , Linfoma Cutáneo de Células T/patología , Linfoma Cutáneo de Células T/sangre , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/sangre , Neoplasias Cutáneas/diagnóstico , Masculino , Femenino , Persona de Mediana Edad , Anciano , Guías de Práctica Clínica como AsuntoRESUMEN
Rice, a critical staple on a global scale, faces escalating challenges in yield preservation due to the rising prevalence of abiotic and biotic stressors, exacerbated by frequent climatic fluctuations in recent years. Moreover, the scorching climate prevalent in the rice-growing regions of South China poses obstacles to the cultivation of good-quality, heavy-grain varieties. Addressing this dilemma requires the development of resilient varieties capable of withstanding multiple stress factors. To achieve this objective, our study employed the broad-spectrum blast-resistant line Digu, the brown planthopper (BPH)-resistant line ASD7, and the heavy-grain backbone restorer lines Fuhui838 (FH838) and Shuhui527 (SH527) as parental materials for hybridization and multiple crossings. The incorporation of molecular markers facilitated the rapid pyramiding of six target genes (Pi5, Pita, Pid2, Pid3, Bph2, and Wxb ). Through a comprehensive evaluation encompassing blast resistance, BPH resistance, cold tolerance, grain appearance, and quality, alongside agronomic trait selection, a promising restorer line, Guihui5501 (GH5501), was successfully developed. It demonstrated broad-spectrum resistance to blast, exhibiting a resistance frequency of 77.33% against 75 artificially inoculated isolates, moderate resistance to BPH (3.78 grade), strong cold tolerance during the seedling stage (1.80 grade), and characteristics of heavy grains (1,000-grain weight reaching 35.64 g) with good grain quality. The primary rice quality parameters for GH5501, with the exception of alkali spreading value, either met or exceeded the second-grade national standard for premium edible rice varieties, signifying a significant advancement in the production of good-quality heavy-grain varieties in the southern rice-growing regions. Utilizing GH5501, a hybrid combination named Nayou5501, characterized by high yield, good quality, and resistance to multiple stresses, was bred and received approval as a rice variety in Guangxi in 2021. Furthermore, genomic analysis with gene chips revealed that GH5501 possessed an additional 20 exceptional alleles, such as NRT1.1B for efficient nitrogen utilization, SKC1 for salt tolerance, and STV11 for resistance to rice stripe virus. Consequently, the restorer line GH5501 could serve as a valuable resource for the subsequent breeding of high-yielding, good-quality, and stress-tolerant hybrid rice varieties.
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Naphtha, as the primary raw material in the production of light olefins, could well accommodate their increasing demand through the energy-efficient process of catalytic cracking with ZSM-5. In the current work, different amounts of lanthanum and phosphorous were loaded on ZSM-5 using the wet impregnation method to tune the acidic properties of ZSM-5 for selective catalytic cracking of n-hexane to produce light olefins. Various characterization techniques such as X-ray diffraction (XRD), Al nuclear magnetic resonance (NMR), temperature-programmed desorption of NH3 (NH3-TPD), Py-Fourier transform infra-red (Py-FTIR), inductively coupled plasma optical emission spectroscopy (ICP-OES), N2 adsorption-desorption, X-ray photoelectron spectra (XPS), and scanning electron microscopy were adopted to investigate the modified zeolites. It was found that adding La to ZSM-5 (0.25 wt% to 1 wt%) improved the catalytic life and increased the n-hexane conversion (to 99.7%), while the further addition had a negative impact, reducing the conversion rate and deviating the product selectivity towards a substantial, undesired benzene, toluene, and xylene (BTX) fraction (33%). On the other hand, a 64% selectivity for light olefins was achieved on phosphorous-doped ZSM-5 (at a loading amount of 1 wt%) while reducing the BTX fraction (2.3%) and converting 69% of the n-hexane. A dual metal-modified ZSM-5 with optimal loading amount, 1P0.25LaZ5 (phosphorus 1 wt% and La 0.25 wt%), helped boost the light olefin selectivity to 62% in the tuned Lewis acid sites at an n-hexane conversion of about 77% while decreasing the undesired BTX selectivity to 3% by reducing the number of Brønsted sites. Thus, the current study reveals that tuning the acidic sites of ZMS-5 by dual metal augmentation with P.La is an effective way of controlling the amount of undesirable BTX produced at a stable n-hexane conversion rate and substantial olefin selectivity.
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Optical traps, including those used in atomic physics, cold chemistry, and quantum science, are widely used in the research on cold atoms and molecules. Owing to their microscopic structure and excellent operational capability, optical traps have been proposed for cold atom experiments involving complex physical systems, which generally induce violent background scattering. In this study, using a background-free imaging scheme in cavity quantum electrodynamics systems, a cold atomic ensemble was accurately prepared below a fiber cavity and loaded into an optical trap for transfer into the cavity. By satisfying the demanding requirements for the background-free imaging scheme in optical traps, cold atoms in an optical trap were detected with a high signal-to-noise ratio while maintaining atomic loading. The cold atoms were then transferred into the fiber cavity using an optical trap, and the vacuum Rabi splitting was measured, facilitating relevant research on cavity quantum electrodynamics. This method can be extended to related experiments involving cold atoms and molecules in complex physical systems using optical traps.
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Translational fidelity relies critically on correct aminoacyl-tRNA supply. The trans-editing factor AlaX predominantly hydrolyzes Ser-tRNAAla, functioning as a third sieve of alanyl-tRNA synthetase (AlaRS). Despite extensive studies in bacteria and archaea, the mechanism of trans-editing in mammals remains largely unknown. Here, we show that human AlaX (hAlaX), which is exclusively distributed in the cytoplasm, is an active trans-editing factor with strict Ser-specificity. In vitro, both hAlaX and yeast AlaX (ScAlaX) were capable of hydrolyzing nearly all Ser-mischarged cytoplasmic and mitochondrial tRNAs; and robustly edited cognate Ser-charged cytoplasmic and mitochondrial tRNASers. In vivo or cell-based studies revealed that loss of ScAlaX or hAlaX readily induced Ala- and Thr-to-Ser misincorporation. Overexpression of hAlaX impeded the decoding efficiency of consecutive Ser codons, implying its regulatory role in Ser codon decoding. Remarkably, yeast cells with ScAlaX deletion responded differently to translation inhibitor treatment, with a gain in geneticin resistance, but sensitivity to cycloheximide, both of which were rescued by editing-capable ScAlaX, alanyl- or threonyl-tRNA synthetase. Altogether, our results demonstrated the previously undescribed editing peculiarities of eukaryotic AlaXs, which provide multiple checkpoints to maintain the speed and fidelity of genetic decoding.