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As one of the six major nutrients, lipids play important roles in various biological processes, including cell membrane construction, signal transduction, and energy metabolism. The diverse functions of lipids are intricately linked to the distinct structures. More than 48 000 molecular lipid structures have been curated in the database which can be further categorized into 8 categories and more than one hundred lipid classes and subclasses. The diverse structures of lipids pose challenges for their lipidomic analysis, especially the co-existence of isomers and isobar. Traditional tandem mass spectrometry (MS/MS) techniques based on collision-induced dissociation (CID) can provide the informations of molecular species and acyl chain composition of various types of lipids in a sensitive fashion. However, they typically fall short in providing detailed structural information, including C=C positions, sn-positions, functional group substitutions and their locations on the fatty acyl chains. In recent years, mass spectrometry methods capable of distinguishing lipid isomers at various structural levels have been developed, among which radical chemistry plays important role in both gas-phase ion activation and chemical derivatization. This article summarized the MS/MS techniques for lipid structural analysis at detailed structural levels via harnessing the power of both radical chemistry and tandem mass spectrometry in the past decade. Radical-induced dissociation (RID) refers to a group of gas-phase dissociation methods which can generate intrachain C-C cleavages in the fatty acyl chain and thus produce fragmentation patterns useful for identification of chain modification. Ultraviolet photodissociation (UVPD) and CID triggered radical-directed dissociation, and electron impact excitation of ions from organics (EIEIO) are the major RID methods. By coupling RID with separation methods, such as reversed-phase liquid chromatography (RPLC), identification and quantitation of lipid isomers consisting of methyl branching, hydroxy group, and cyclopropane modification and their locations have been achieved. The two major derivatization methods utilizing radical chemistry for C=C bond modification were discussed, including radical initiated epoxidation reactions and the Paternò-Büchi reaction. Furthermore, the future direction of combining radical chemistry and tandem mass spectrometry for deep lipidotyping was discussed, which included the coupling with advanced separation methods, integrated workflows for multi-level structure analysis, and development of automated annotation tools for data analysis.

Abstract Clarifying the underlying mechanisms that govern ordering transitions in condensed matter systems is crucial for comprehending emergent properties and phenomena. While transitions are often classified as electronically driven or lattice-driven, we present a departure from this conventional picture in the case of the double perovskite Ba2MgReO6. Leveraging resonant and non-resonant elastic x-ray scattering techniques, we unveil the simultaneous ordering of structural distortions and charge quadrupoles at a critical temperature of T q ~ 33 K. Using a variety of complementary first-principles-based computational techniques, we demonstrate that, while electronic interactions drive the ordering at T q, it is ultimately the lattice distortions that dictate the specific ground state that emerges. Our findings highlight the crucial interplay between electronic and lattice degrees of freedom, providing a unified framework to understand and predict unconventional emergent phenomena in quantum materials.

Background: Coxiella burnetii is a zoonotic pathogen that causes Q fever and is found worldwide. Ticks serve as the primary reservoir, playing an important role in maintaining the natural cycle of C. burnetii. C. burnetii is transmitted to animals when ticks feed on their blood. However, information on C. burnetii infection in ticks remains limited, despite the widespread prevalence of the infection in humans and animals across China. Methods: In this study, 192 engorged ticks were collected from Baiyin City of Gansu Province, China. The presence of Coxiella burnetii in ticks was specifically identified by detecting the IS1111 gene using nested polymerase chain reaction (nPCR). In addition, the 16S rRNA gene of C. burnetii was molecularly characterized using nPCR. A total of 10 spacer sequences (Cox 2, 5, 18, 20, 22, 37, 51, 56, 57, and 61) were amplified using PCR against positive specimens for MST analysis. Results: All collected ticks were identified as Hyalomma marginatum , and 90 of them tested positive for C. burnetii , with a positive rate of 46.9% (90/192). The 16S rRNA gene analysis showed that the novel C. burnetii variants detected in this study were closely related to other C. burnetii strains in the world. The allele codes found in the present study for loci Cox2-Cox5-Cox18-Cox20-Cox22-Cox37-Cox51-Cox56-Cox57-Cox61 were 8-4-9-5-7-5-2-3-11-6. This represents a novel combination of allele values, similar to MST28, currently designated as MST85 in the Multi Spacers Typing (MST) database. Conclusion: Our results revealed the circulation of a novel MST genotype of C. burnetii in Baiyin City, Gansu Province, China. The detection of C. burnetii in ticks suggests a potential public health risk to the local human population. [ABSTRACT FROM AUTHOR]

Clarifying the underlying mechanisms that govern ordering transitions in condensed matter systems is crucial for comprehending emergent properties and phenomena. While transitions are often classified as electronically driven or lattice-driven, we present a departure from this conventional picture in the case of the double perovskite Ba2MgReO6. Leveraging resonant and non-resonant elastic x-ray scattering techniques, we unveil the simultaneous ordering of structural distortions and charge quadrupoles at a critical temperature of Tq ~ 33 K. Using a variety of complementary first-principles-based computational techniques, we demonstrate that, while electronic interactions drive the ordering at Tq, it is ultimately the lattice distortions that dictate the specific ground state that emerges. Our findings highlight the crucial interplay between electronic and lattice degrees of freedom, providing a unified framework to understand and predict unconventional emergent phenomena in quantum materials. Charge quadrupole order was predicted in several 5d1 and 5d2 double perovskite systems, but experimental verification has been challenging. Here the authors provide experimental and theoretical evidence of simultaneous charge quadrupole order and local structural distortions in Ba2MgReO6. [ABSTRACT FROM AUTHOR]

This study examined the effects of hot air drying (HAD), infrared radiation drying (IRD), microwave vacuum drying (MVD), freeze drying (FD), and freeze drying combined with microwave vacuum drying (FD-MVD) on the drying kinetics, color, rehydration ratio, titratable acidity, and vitamin C content of small white apricots (Prunus armeniaca L.). Results showed drying times of 12.5 h (IRD), 14.1 h (FD), 16 h (HAD), 0.53 h (MVD), and 6.15 h (FD-MVD). FD-MVD significantly outperformed MVD, HAD, and IRD in color, vitamin C, titratable acidity, and rehydration, though was slightly inferior to FD. Microstructural analysis revealed that FD-MVD preserved the most uniform pore structure, better maintaining apricots' original appearance. In contrast, IRD and HAD caused severe surface shriveling, compromising quality. In conclusion, FD-MVD emerges as a promising drying method to enhance apricot quality and market competitiveness in food processing. [ABSTRACT FROM AUTHOR]

To enhance the fire protection level of critical infrastructure through scientific risk assessment, a dynamic risk assessment framework is proposed in this study. This framework, which was developed based on the principles and techniques of system safety engineering, caters to the unique features of critical infrastructure. The framework facilitates dynamic risk assessment of critical infrastructure and serves as a key driver for its advancement. Fault Tree Analysis is applied for the main failure analysis, which functioned to understand the causes of system failure and find the best way to control the risks. Event Tree Analysis is used to accident consequence analysis and simulated the accident process. Analytic Hierarchy Process is utilized for risk assessment indicators and weight calculation, with a novel approach to expert weight allocation and a dynamic indicator system. Based on the aforementioned methods, a systematic assessment of fire risk is conducted for the ultra‐high voltage (UHV) converter transformer by identifying potential hazards, main failures, and accident consequences. A dynamic indicator system is then established for the assessment of fire risk associated with the UHV converter transformer. [ABSTRACT FROM AUTHOR]

Abstract Exotic quantum phases, arising from a complex interplay of charge, spin, lattice and orbital degrees of freedom, are of immense interest to a wide research community. A well-known example of such an entangled behavior is the Jahn-Teller effect, where the lifting of orbital degeneracy proceeds through lattice distortions. Here we demonstrate that a highly-symmetrical 5d1 double perovskite Ba2MgReO6, comprising a 3D array of isolated ReO6 octahedra, represents a rare example of a dynamic Jahn-Teller system in the strong spin-orbit coupling regime. Thermodynamic and resonant inelastic x-ray scattering experiments, supported by quantum chemistry calculations, undoubtedly show that the Jahn-Teller instability leads to a ground-state doublet, resolving a long-standing puzzle in this family of compounds. The dynamic state of ReO6 octahedra persists down to the lowest temperatures, where a multipolar order sets in, allowing for investigations of the interplay between a dynamic JT effect and strongly correlated electron behavior.

Abstract Quantum spin liquids (QSLs) have become a key area of research in magnetism due to their remarkable properties, such as long-range entanglement, fractional excitations, and topologically protected phenomena. Recently, the search for QSLs has expanded into the three-dimensional world, despite the suppression of quantum fluctuations due to high dimensionality. A new candidate material, K2Ni2(SO4)3, belongs to the langbeinite family and consists of two interconnected trillium lattices. Although magnetically ordered, it exhibits a highly dynamical and correlated state. In this work, we combine inelastic neutron scattering measurements with density functional theory (DFT), pseudo-fermion functional renormalization group (PFFRG), and classical Monte Carlo (cMC) calculations to study the magnetic properties of K2Ni2(SO4)3, revealing a high level of agreement between experiment and theory. We further reveal the origin of the dynamical state in K2Ni2(SO4)3 to be centred around a magnetic network composed of tetrahedra on a trillium lattice.

Abstract In the rapidly expanding field of topological materials there is growing interest in systems whose topological electronic band features can be induced or controlled by magnetism. Magnetic Weyl semimetals, which contain linear band crossings near the Fermi level, are of particular interest owing to their exotic charge and spin transport properties. Up to now, the majority of magnetic Weyl semimetals have been realized in ferro- or ferrimagnetically ordered compounds, but a disadvantage of these materials for practical use is their stray magnetic field which limits the minimum size of devices. Here we show that Weyl nodes can be induced by a helical spin configuration, in which the magnetization is fully compensated. Using a combination of neutron diffraction and resonant elastic x-ray scattering, we find that below T N = 14.5 K the Eu spins in EuCuAs develop a planar helical structure which induces two quadratic Weyl nodes with Chern numbers C = ±2 at the A point in the Brillouin zone.

Abstract In quantum magnetic materials, ordered phases induced by an applied magnetic field can be described as the Bose-Einstein condensation (BEC) of magnon excitations. In the strongly frustrated system SrCu2(BO3)2, no clear magnon BEC could be observed, pointing to an alternative mechanism, but the high fields required to probe this physics have remained a barrier to detailed investigation. Here we exploit the first purpose-built high-field neutron scattering facility to measure the spin excitations of SrCu2(BO3)2 up to 25.9 T and use cylinder matrix-product-states (MPS) calculations to reproduce the experimental spectra with high accuracy. Multiple unconventional features point to a condensation of S = 2 bound states into a spin-nematic phase, including the gradients of the one-magnon branches and the persistence of a one-magnon spin gap. This gap reflects a direct analogy with superconductivity, suggesting that the spin-nematic phase in SrCu2(BO3)2 is best understood as a condensate of bosonic Cooper pairs.

This study examined the effects of hot air drying (HAD), infrared radiation drying (IRD), microwave vacuum drying (MVD), freeze drying (FD), and freeze drying combined with microwave vacuum drying (FD-MVD) on the drying kinetics, color, rehydration ratio, titratable acidity, and vitamin C content of small white apricots (Prunus armeniaca L.). Results showed drying times of 12.5 h (IRD), 14.1 h (FD), 16 h (HAD), 0.53 h (MVD), and 6.15 h (FD-MVD). FD-MVD significantly outperformed MVD, HAD, and IRD in color, vitamin C, titratable acidity, and rehydration, though was slightly inferior to FD. Microstructural analysis revealed that FD-MVD preserved the most uniform pore structure, better maintaining apricots’ original appearance. In contrast, IRD and HAD caused severe surface shriveling, compromising quality. In conclusion, FD-MVD emerges as a promising drying method to enhance apricot quality and market competitiveness in food processing.

It is important to systematically identify tumor suppressor genes (TSGs) to improve our understanding of tumorigenesis and develop strategies for early diagnosis and mitigating disease progression. In the present study, we used an in vivo genome-wide clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein 9 (Cas9) screen and identified FPS/FES-related (FER) as a TSG. Single-cell RNA sequencing (scRNA-seq) revealed that normal cells with low FER expression exhibited elevated malignant transformation potential and stemness properties. FER knockout promoted the tumorigenic transformation, characterized by high colony-forming efficiency and suspension growth ability, acquired tumorigenicity in vivo, increased metabolic activity, dedifferentiation properties, and immune evasion. Moreover, analysis revealed that low FER expression tumors share molecular phenotypes with FER knockout cells, suggesting the consistent role of FER in tumor initiation and progression. Taken together, our findings not only provide insights into the essential role of FER as a tumor suppressor in tumor initiation and progression but also highlight its potential as a target for future clinical diagnosis. © 2024 The Pathological Society of Great Britain and Ireland., (© 2024 The Pathological Society of Great Britain and Ireland.)

The aim of the present study was to provide a theoretical basis for the selection of standard sampling methods in the study of the esophageal microbiota in patients with esophageal squamous cell carcinoma (ESCC) by comparing the differences in bacterial communities between surgical and endoscopic esophageal mucosal tissues. A total of 72 patients with ESCC who were diagnosed at Taihe Hospital (Shiyan, China) between July 2018 and July 2019 were selected to participate in the present study. The sequence V 4 hypervariable region was amplified, and Illumina HiSeq sequencing was performed to analyze the differences between the two groups. The Shannon and Chao1 indices of the postoperative esophageal cancer tissue group samples (Group A) were higher than those of the esophageal mucosa tissue samples (Group B), and the difference was statistically significant (P<0.05). The Simpson index of Group A was higher than that of Group B, but the difference was not significant (P>0.05). The β diversity analysis demonstrated that the overall composition of the flora of the two groups was not significantly different. Linear discriminant analysis effect size analysis showed that the abundance of Megasphaera, Actinobacteria, Enterobacteriaceae and Enterobacteriales in Group A was significantly higher than that in Group B, but the abundance of Mogibacteriaceae in Group B was significantly higher than that in Group A. The top 60 species were selected using the random forest method to establish a model. The error rate of the prediction model constructed using the random forest method was 22.59%. The receiver operating characteristic (ROC) curve analysis confirmed that the present model was reliable and could effectively distinguish between the two groups of samples (area under the curve, 0.86). The source of the sample should be considered in studies investigating the esophageal flora. Considering the increased richness and improved uniformity of postoperative tissue microbiota compared with the mucosal group, it was predicted that postoperative tissue may be more conducive to the study of esophageal cancer microbiota., Competing Interests: The authors declare that they have no competing interests., (Copyright: © 2024 Liu et al.)

A new species of nematode, Molinostrongylus longmenensis n.sp., parasite of the genus Molinostrongylus , is described based on specimens recovered from the small intestine of Scotophilus kuhlii Leach, 1822 (Chiroptera: Vespertilionidae) in Longmen County, Guangdong Province, China. To date, 135 species of bat-parasitic nematodes have been reported worldwide. Overall, 13 species belonging to seven genera in three families have been described in China. The new species is characterized by the presence of three ventral and three dorsal longitudinal cuticular ridges perpendicular to the body surface, which appear posterior to the cephalic vesicle and extend to the caudal bursa in males and the posterior end in females. The female tail has two medium-sized subventral conical processes of equal length, as well as one large dorsal conical process, and one thin spine, lateral alae that extend to the position of the vulva, with a fin-like ending. In addition, the new species was also characterized using molecular approaches, such as sequencing and analyzing the internal transcribed spacer 1 (ITS-1) of the ribosomal DNA., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Ju, Jian, Wang, Qin, Gao, Xu and Zhang.)