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ABSTRACT Importance Postzygotic mutations in the GNAQ/GNA11 genes, which encode the G‐protein nucleotide binding protein alpha subunits, have been identified in patients with phakomatosis pigmentovascularis (PPV). However, little is known about the Chinese population. Objective To identify pathogenic mutations in pediatric patients with PPV within the Chinese population. Methods We performed whole‐exome sequencing (WES) using skin lesion tissues from pediatric patients diagnosed with PPV. Additionally, ultradeep‐targeted sequencing was conducted to validate the somatic mutations. A genotype‐phenotype correlation was analyzed by integrating data from previous reports with the findings of the present study. Results Thirteen patients were enrolled, all diagnosed with the cesioflammea type of PPV, except for one patient with an unclassifiable type. We identified somatic GNA11 c.547C>T (p.R183C) variant in seven patients and GNAQ c.548G>A (p.R183Q) in four patients, with low allelic fractions ranging from 2.1% to 8.6% through ultradeep sequencing. Besides, a GNAQ c.548G>A (p.R183Q) variant was detected through targeted sequencing in one of two patients who did not exhibit detectable variants via WES. The genotype‐phenotype correlation analysis, involving 15 patients with a GNA11 variant and 10 with a GNAQ variant, revealed that facial capillary malformation (87% vs. 50%, P = 0.075) and ocular melanocytosis (80% vs. 40%, P = 0.087) appeared to be more frequent in patients with GNA11 mutation compared to those with GNAQ mutations. All four patients diagnosed with cesiomarmorata type or overlapping cesioflammea and cesiomarmorata type PPV carried the GNA11 variant. Interpretation Our study demonstrated that the majority of PPV patients in the Chinese population carried a postzygotic variant of GNAQ/GNA11, thus further confirming the pathogenic role of GNAQ/GNA11 mosaicism in the development of PPV cesioflammea type.

Abstract Chloroplast genomes, pivotal for understanding plant evolution, remain unexplored in Rutaceae, a family with key perennial crops like citrus. Leveraging next-generation sequencing data from 509 Rutaceae accessions across 15 species, we conducted a de novo assembly of 343 chloroplast genomes, unveiling a chloroplast variation map highlighting the heterogeneous evolution rates across genome regions. Notably, differences in chloroplast genome size primarily originate from large single-copy and small single-copy regions. Structural variants predominantly occurred in the single-copy region, with two insertions located at the single-copy and inverted repeat region boundary. Phylogenetic analysis, principal component analysis, and population genetic statistics confirmed the cohesive clustering of different Citrus species, reflecting evolutionary dynamics in Citrus diversification. Furthermore, a close chloroplast genetic affinity was revealed among Atalantia (previously regarded as primitive citrus), Clausena, and Murraya. Zanthoxylum formed a distinct group with heightened genetic diversity. Through expanding our analysis to include 34 published chloroplast genomes, we explored chloroplast gene selection, revealing divergent evolutionary trends in photosynthetic pathways. While Photosystem I and Photosystem II exhibited robust negative selection, indicating stability, the Nicotinamide adenine dinucleotide (NADH) dehydrogenase pathway demonstrated rapid evolution, which was indicative of environmental adaptation. Finally, we discussed the effects of gene length and GC content on chloroplast gene evolution. In conclusion, our study reveals the genetic characterization of chloroplast genomes during Rutaceae diversification, providing insights into the evolutionary history of this family.

The aim of this paper is to investigate the effect of micro grooves on the lubrication performance of gas-lubricated inclined slider bearing. This paper is based on numerical analysis. The detailed numerical investigation is carried out in matlab software. The grooving parameters are optimized to obtain the maximum average pressure for various inclination angles of gas-lubricated inclined slider bearing. The results show that the inclination angle of the micro-grooves, depth of the micro-grooves, width of the micro-grooves, and spacing of the micro-grooves have an important influence on the hydrodynamic pressure of gas-lubricated inclined slider bearing with micro-grooves. Besides, the influence of the sliding speed on average pressure increment for various inclination angles of gas-lubricated inclined slider bearing is investigated. It is observed that the sliding speed generating the maximum average pressure increment is dependent on the inclination angle of gas-lubricated inclined slider bearing.

Rapid and accurate identification and detection of illicit drugs are important for combating drug crimes. As a newly developed technology, shifted-excitation Raman difference spectroscopy (SERDS) can greatly reduce the interference caused by fluorescence and improve the potential of Raman for distinguishing drug compounds in seized samples with fluorescent additives. In this work, 43 random seized drugs were scanned and analyzed by both SERDS and ordinary portable Raman spectrometers for the first time. The detected results of two Raman technologies were confirmed with gas chromatographic mass spectrometry test results, and compared in detail in the aspects of detection rate and matching accuracy. SERDS had significant advantages in eliminating fluorescence interference with a very high detection rate of 93.0%, compared with 53.3% obtained by an ordinary Raman spectrometer, although the ordinary Raman spectrometer analyzed the composition of multi-component mixed samples with higher accuracy. To some extent, the two Raman spectrometers realized functional complementarity, and a rational use of the two types of Raman spectrometers may be of benefit in the rapid detection of seized drugs., Drugs as illicit substances, including methamphetamine, ketamine, methylene dioxymethamphetamine (MDMA), diamorphine and so on, can cause euphoria, hallucination, and addiction (1). Of drugs seized by authorities, the most common in [...]