146 research outputs found
Integrated Transcriptome and Metabolic Analyses Reveals Novel Insights into Free Amino Acid Metabolism in Huangjinya Tea Cultivar
Creación de personaje en la técnica clown de la puesta en escena "Los merolicos"
La creación de personaje en la técnica clown para la puesta en escena “Los merolicos
Contraction and expansion dynamics: deciphering genomic underpinnings of growth rate and pathogenicity in Mycobacterium
BackgroundMycobacterium bacteria, encompassing both slow growth (SGM) and rapid growth mycobacteria (RGM), along with true pathogenic (TP), opportunistic pathogenic (OP), and non-pathogenic (NP) types, exhibit diverse phenotypes. Yet, the genetic underpinnings of these variations remain elusive.MethodsHere, We conducted a comprehensive comparative genomics study involving 53 Mycobacterium species to unveil the genomic drivers behind growth rate and pathogenicity disparities.ResultsOur core/pan-genome analysis highlighted 1,307 shared gene families, revealing an open pan-genome structure. A phylogenetic tree highlighted clear boundaries between SGM and RGM, as well as TP and other species. Gene family contraction emerged as the primary alteration associated with growth and pathogenicity transitions. Specifically, ABC transporters for amino acids and inorganic ions, along with quorum sensing genes, exhibited significant contractions in SGM species, potentially influencing their distinct traits. Conversely, TP strains displayed contraction in lipid and secondary metabolite biosynthesis and metabolism-related genes. Across the 53 species, we identified 26 core and 64 accessory virulence factors. Remarkably, TP and OP strains stood out for their expanded mycobactin biosynthesis and type VII secretion system gene families, pivotal for their pathogenicity.ConclusionOur findings underscore the importance of gene family contraction in nucleic acids, ions, and substance metabolism for host adaptation, while emphasizing the significance of virulence gene family expansion, including type VII secretion systems and mycobactin biosynthesis, in driving mycobacterial pathogenicity
Absolute frequency measurements with a robust, transportable ^{40}Ca^{+} optical clock
We constructed a transportable 40Ca+ optical clock (with an estimated minimum
systematic shift uncertainty of 1.3*10^(-17) and a stability of
5*10^(-15)/sqrt{tau} ) that can operate outside the laboratory. We transported
it from the Innovation Academy for Precision Measurement Science and
Technology, Chinese Academy of Sciences, Wuhan to the National Institute of
Metrology, Beijing. The absolute frequency of the 729 nm clock transition was
measured for up to 35 days by tracing its frequency to the second of
International System of Units. Some improvements were implemented in the
measurement process, such as the increased effective up-time of 91.3 % of the
40Ca+ optical clock over a 35-day-period, the reduced statistical uncertainty
of the comparison between the optical clock and hydrogen maser, and the use of
longer measurement times to reduce the uncertainty of the frequency
traceability link. The absolute frequency measurement of the 40Ca+ optical
clock yielded a value of 411042129776400.26 (13) Hz with an uncertainty of
3.2*10^(-16), which is reduced by a factor of 1.7 compared with our previous
results. As a result of the increase in the operating rate of the optical
clock, the accuracy of 35 days of absolute frequency measurement can be
comparable to the best results of different institutions in the world based on
different optical frequency measurements.Comment: 15 pages, 5 figure
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A systematic review of factors influencing signage salience in indoor environments
Wayfinding signage is an intermediary public facility that coordinates the relationship between space and people, and it is crucial to help people find their way in complex indoor environments. In people’s cognitive behaviour towards wayfinding signs, the visual salience of the signs is the prerequisite and key to ensuring their effective operation. This paper aims to review published research articles on the effect of indoor environments on the saliency of wayfinding signs. The literature review was conducted by PICO methodology to formulate the research question and develop search strategies. Relevant research articles were identified by systematically searching electronic databases, including Web of Science, ScienceDirect, ProQuest, and EBSCO. This paper summarises two categories of factors influencing signage salience: (1) floor plan factors and (2) environmental factors. This study examined and condensed the attributes of wayfinding signage and their impact on how pedestrians perceive visuals while navigating. Exploring the elements that influence the visual prominence of indoor signs enhances our comprehension of how pedestrians engage with visually guided information indoors. Furthermore, this offers a theoretical foundation for the realm of indoor wayfinding
Systemic Analysis of the DNA Replication Regulator MCM Complex in Ovarian Cancer and Its Prognostic Value
Microliposome maintenance (MCM) 2, MCM3, MCM4, MCM5, MCM6, and MCM7 are DNA replication regulators and are involved in the progression of multiple cancer types, but their role in ovarian cancer is still unclear. The purpose of this study is to clarify the biological function and prognostic value of the MCM complex in ovarian cancer (OS) progression. We analyzed DNA alterations, mRNA and protein levels, protein structure, PPI network, functional enrichment, and prognostic value in OC based on the Oncomine, cBioPortal, TCGA, CPTAC, PDB, GeneMANIA, DAVID, KEGG, and GSCALite databases. The results indicated that the protein levels of these DNA replication regulators were increased significantly. Moreover, survival analysis showed a prognostic signature based on the MCM complex, which performed moderately well in terms of OS prognostic prediction. Additionally, protein structure, functional enrichment, and PPI network analyses indicated that the MCM complex synergistically promoted OC progression by accelerating DNA replication and the cell cycle. In conclusion, our study suggested that the MCM complex might be a potential target and prognostic marker for OC patients
Cassava genome from a wild ancestor to cultivated varieties
Cassava is a major tropical food crop in the Euphorbiaceae family that has high carbohydrate production potential and adaptability to diverse environments. Here we present the draft genome sequences of a wild ancestor and a domesticated variety of cassava and comparative analyses with a partial inbred line. We identify 1,584 and 1,678 gene models specific to the wild and domesticated varieties, respectively, and discover high heterozygosity and millions of single-nucleotide variations. Our analyses reveal that genes involved in photosynthesis, starch accumulation and abiotic stresses have been positively selected, whereas those involved in cell wall biosynthesis and secondary metabolism, including cyanogenic glucoside formation, have been negatively selected in the cultivated varieties, reflecting the result of natural selection and domestication. Differences in microRNA genes and retrotransposon regulation could partly explain an increased carbon flux towards starch accumulation and reduced cyanogenic glucoside accumulation in domesticated cassava. These results may contribute to genetic improvement of cassava through better understanding of its biology
Identification of a stable major-effect QTL (Parth 2.1) controlling parthenocarpy in cucumber and associated candidate gene analysis via whole genome re-sequencing
Temperature dependent photoexcited carrier dynamics in multiferroic BiFeO3 film: a hidden phase transition
The ultrafast carrier dynamics of the multiferroic BiFeO3 film in a broad temperature range is investigated using optical pump-probe spectroscopy. The photoexcited electrons release their energy with optical phonons emission through electron-phonon coupling in about 1 ps. The following intermediate process is identified as dynamical spin-lattice coupling in several picoseconds. Furthermore, the peak values of the optical reflectivity and the time constants of carrier relaxation channels show significant changes while the temperature varies from 137.5 K to around 195 K, this aligns with the previously reported hidden phase transition. Our study demonstrates that ultrafast spectroscopy is a sensitive method to look into the dynamical interactions among the on-site high-energy electrons accumulated in the p conduction band of Bi, coherent optical phonon, as well as the spin degree of freedom. These features play crucial roles in the characterization of phase transitions
Insights on the Formation Mechanism of Ultra-Low Friction of Phenolic Resin Graphite at High Temperature
In the present paper, the influences of high temperature on the tribological properties of phenolic resin graphite (PRG) sliding against tungsten carbide-nickel (WC-Ni) alloy in ambient air were investigated systematically. Results demonstrated that the antifriction behaviors of PRG was sensitive to high temperature and PRG exhibits ultra-low coefficient of friction (CoF) of about 0.01–0.015. The low CoF is attributed to the formation of graphite tribofilms, which shows different formation processes on the contact interface at different temperatures (room temperature, 200, 300 and 400 °C). These findings provide insight into the formation mechanism of graphite tribofilms, and provide an important basis for improving the tribological properties of graphite-based friction materials and manufacturing new graphite for seal applications
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