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In order to find an excellent drying method for Panax notoginseng leaves (PNL), PNL were dried by using hot air drying (HAD), heat pump drying (HPD) or vacuum drying (VD). The contents of total saponins, polysaccharides, total phenols, total flavonoids, and monomer saponins, in vitro antioxidant activity and α-glucosidase inhibitory capacity of fresh and dried PNL were determined. By using gas chromatography-ion mobility spectrometry (GC-IMS) and non-targeted metabolomics, the volatile components and metabolites in fresh and dried PNL were identified and analyzed, respectively. The results showed that all three drying methods could significantly increase the contents of total saponins and polysaccharides in PNL, reduce the contents of total phenols and total flavonoids, but decrease the functional activities of PNL to varying degrees. Among the four samples, the HPD dried sample had the highest contents of total saponins and polysaccharides, the strongest 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity and α-glucosidase inhibitory capacity, and moderately strong 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) cation radical scavenging capacity and ferric ion reducing antioxidant power (FRAP). High-performance liquid chromatography (HPLC) analysis showed that HPD treatment significantly reduced the contents of notoginsenosides Fc and Fe, while VD treatment showed the opposite effect. A total of 85 volatile components were detected, and the HPD dried sample showed the highest relative contents of alcohols and aldehydes, and the lowest relative content of ketones. In addition, there were significant differences between treatment groups. Furthermore, ultra-high performance liquid chromatography-quadrupole-orbitrap mass spectrometry (UPLC-Q-OT-MS) identified 659 metabolites in the fresh and HPD dried samples. In the positive and negative ion modes, 113 and 68 metabolites were significantly up-regulated, and 98 and 31 metabolites were significantly down-regulated, respectively. These differential metabolites predominately included lipids, lipid-like molecules, organic heterocyclic compounds, organic acids and their derivatives. Out of the 24 saponins in PNL, seven were significantly down-regulated and one was significantly up-regulated, which verified the HPLC results. Through the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of differential metabolites, it was found that the most likely metabolic pathways in HPD dried PNL included the biosynthesis of amino acids, 2-oxycarboxylic acid metabolism, and the biosynthesis of cofactors. In conclusion, HPD provided the best preservation of the chemical composition and functional activities of PNL, making it more suitable for drying PNL. Through multiple metabolite pathways, HPD could alter the composition of metabolites in PNL and affect its volatile components.

In this study, by using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and double-sandwich enzyme-linked immunosorbent assay (ELISA), Juglans sigillata kernels from seven different production areas in Yunnan province were screened for their Jug r 1 contents. The preparation of Jug r 1 through ammonium sulfate precipitation, gel filtration chromatography (GFC), and liquid chromatography-tandem mass spectrometry (LC-MS/MS) was optimized and the product was identified. Its structure was characterized by circular dichroism (CD) spectroscopy. Finally, Jug r 1 content in walnut protein was measured by ELISA. The results showed that walnuts from Baoshan, which had the highest contents of total protein and Jug r 1, were used for subsequent experiments. The optimal concentration of ammonium sulfate saturation was in the range from 40% to 80%, and the optimal conditions for GFC were sample concentration of 30 mg/mL, loading volume of 4 mL, and elution flow rate of 1 mL/min. Under these conditions, the recovery of Jug r 1 was 16.58%. Mass spectrometry analysis showed that this protein had the typical characterisitcs of Jug r 1. Circular dichroism spectroscopy indicated that the secondary structure of Jug r 1 was dominated by α-helix and consisted of multiple conformations. After separation and purification by a two-step process, Jug r 1 with purity more than 96% was obtained. This study can provide a scientific basis for further research on Jug r 1 and also provide a reference for the separation and purification of allergic proteins from other nuts.

The Lucaogou Formation, a typical fine-grained mixed formation in the Jimusaer Sag of the Junggar Basin, exhibits considerable potential for hydrocarbon exploration. Accurate brittle prediction is a crucial factor in determining hydraulic fracturing effectiveness. However, the area features complex lithological characteristics, including carbonate rocks, clastic rocks, volcanic rocks, and gypsum interbeds, along with thin layering and sporadic sweet spots. Traditional prediction methods offer limited resolution and there is an urgent need for a seismic brittle prediction method tailored to this complex geological environment. This paper presents a multi-mineral composition equivalent model for complex lithologies that enables the accurate calculation of Vp and Vs These ratios serve as the foundation for pre-stack elastic parameter predictions, which include Poisson’s ratio and Young’s modulus. By comparing the predicted parameters with well-logging measurements, the prediction accuracy is improved to 82%, with particularly high conformity in intervals characterized by high organic matter and clay content. Additionally, a three-dimensional brittle modeling approach reveals that the brittleness of the reservoir exceeds that of the surrounding rock, showing a gradual improvement in brittleness with increasing burial depth from southeast to northwest. The central area exhibits relatively good brittleness, with a stable, blocky distribution pattern.

A 3‐graph F ${\rm{ {\mathcal F} }}$ is U(s,2s+1) $U(s,2s+1)$ if for any s $s$ edges e1,...,es∈E(F) ${e}_{1},\ldots ,{e}_{s}\in E({\rm{ {\mathcal F} }})$, ∣e1∪⋯∪es∣≤2s+1 $| {e}_{1}\cup \cdots \cup {e}_{s}| \le 2s+1$. Frankl and Kupavskii proposed the following conjecture: For any 3‐graph F ${\rm{ {\mathcal F} }}$ with n $n$ vertices, if F ${\rm{ {\mathcal F} }}$ is U(s,2s+1) $U(s,2s+1)$, then e(F)≤maxn−12,(n−s−1)s+12+s+13,2s+13. $\begin{array}{c}e({\mathscr{F}})\le \max \left\{\left(\genfrac{}{}{0ex}{}{n-1}{2}\right),(n-s-1)\left(\genfrac{}{}{0ex}{}{s+1}{2}\right)\right.\\ \,\left.+\left(\genfrac{}{}{0ex}{}{s+1}{3}\right),\left(\genfrac{}{}{0ex}{}{2s+1}{3}\right)\right\}.\end{array}$ In this paper, we confirm Frankl and Kupavskii's conjecture. [ABSTRACT FROM AUTHOR]

Long noncoding RNAs (lncRNAs) and promoter- or enhancer-associated unstable transcripts locate preferentially to chromatin, where some regulate chromatin structure, transcription and RNA processing.sup.1-13. Although several RNA sequences responsible for nuclear localization have been identified--such as repeats in the lncRNA Xist and Alu-like elements in long RNAs.sup.14-16--how lncRNAs as a class are enriched at chromatin remains unknown. Here we describe a random, mutagenesis-coupled, high-throughput method that we name 'RNA elements for subcellular localization by sequencing' (mutREL-seq). Using this method, we discovered an RNA motif that recognizes the U1 small nuclear ribonucleoprotein (snRNP) and is essential for the localization of reporter RNAs to chromatin. Across the genome, chromatin-bound lncRNAs are enriched with 5' splice sites and depleted of 3' splice sites, and exhibit high levels of U1 snRNA binding compared with cytoplasm-localized messenger RNAs. Acute depletion of U1 snRNA or of the U1 snRNP protein component SNRNP70 markedly reduces the chromatin association of hundreds of lncRNAs and unstable transcripts, without altering the overall transcription rate in cells. In addition, rapid degradation of SNRNP70 reduces the localization of both nascent and polyadenylated lncRNA transcripts to chromatin, and disrupts the nuclear and genome-wide localization of the lncRNA Malat1. Moreover, U1 snRNP interacts with transcriptionally engaged RNA polymerase II. These results show that U1 snRNP acts widely to tether and mobilize lncRNAs to chromatin in a transcription-dependent manner. Our findings have uncovered a previously unknown role of U1 snRNP beyond the processing of precursor mRNA, and provide molecular insight into how lncRNAs are recruited to regulatory sites to carry out chromatin-associated functions. Long noncoding RNAs and certain unstable transcripts tend to localize to chromatin, in a process that is shown here to depend on an RNA motif that recognizes the small nuclear ribonuclear protein U1, and to rely on transcription., Author(s): Yafei Yin [sup.1] , J. Yuyang Lu [sup.1] , Xuechun Zhang [sup.1] , Wen Shao [sup.1] , Yanhui Xu [sup.1] , Pan Li [sup.1] [sup.2] , Yantao Hong [sup.1] [...]

To reduce the manufacturing cost of integrated circuits, the size of the silicon wafer has become larger, with the diameter increasing from 200 to 450 mm. The large diameter silicon wafer poses challenges to the manufacturing process, as its surface profile is more difficult to control and the planarization process is harder to optimize in mass production. Based on different types of contact, gap adjustment and convex pad dressing methods were proposed in this paper to control the pressure distribution on the wafer, which further influenced the wafer profile. Pressure distributions with different gap values and different pad profiles were explained with contact mechanics and verified by simulations. The simulation results show that a negative gap value and a convex pad profile contribute to the improvement of the pressure uniformity on the wafer. Both methods were then applied in the double-sided planarization (DSP) process of 300 mm silicon wafers. The results from the test run of the DSP process show that wafer flatness is improved with a negative gap value. This indicates that gap adjustment is an effective approach for wafer profile control. In the subsequent mass production of the DSP process, silicon wafers with a global flatness of 120 nm and a site flatness of 21.7 nm were obtained. [ABSTRACT FROM AUTHOR]