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The AV3Sb5 prototype kagome materials have been demonstrated as a versatile platform for exploring exotic properties in condensed matter physics, including charge density waves, superconductivity, non-trivial electron topology, as well as topological superconductivity. Here we identify that ANb3Bi5 (A = K, Rb, Cs) exhibit non-trivial coexisting superconductivity and topological properties via first-principles calculations. The negative formation energy and the absence of imaginary phonon dispersion demonstrate both thermodynamics and dynamics stabilities of ANb3Bi5 (A = K, Rb, Cs) under ambient conditions. By analytically solving the Allen-Dynes-modified McMillan formula, the superconducting transition temperatures are predicted to be 2.11, 2.15 and 2.21 K for KNb3Bi5, RbNb3Bi5, and CsNb3Bi5, respectively. More importantly, the kagome materials proposed here can be classified into Z 2 topological metals due to the non-trivial topological index and the obvious surface states around the Fermi level. Such coexistence of superconductivity and non-trivial band characters in ANb3Bi5 (A = K, Rb, Cs) offer us more insights to study the relationship between superconductivity and topological properties, and to design innate topological superconductors. [ABSTRACT FROM AUTHOR]

Chlorite is present extensively in many types of deposits. The mechanism underlying the chemical variations in chlorite remains unclear. The Naruo porphyry deposit is a giant copper porphyry deposit in the Duolong ore district of Tibet. Chlorite, which is abundant in this deposit, has yet to be studied systematically; hence, we used principal component analysis (PCA) to assess the correlation between chlorite elements and various types of mineral deposits. We then conducted a preliminary investigation into its mineralogy and geochemistry to better understand its formation process and identify potential prospecting indicators. The PCA method proved effective in discerning two distinctive element signatures within the chlorite and categorising them into four deposit types: orogenic Au deposits, granite-type U deposits, and skarn-type Sn deposits that exhibit high FeOand low MgO distinguishing them from porphyry copper deposits. The chlorite in the Naruo deposit is classified as either early metasomatic (M-type), consisting mainly of clinochlore, or late hydrothermal (H-type), primarily consisting of clinochlore and chamosite. This classification suggests that H-type chlorite formed in a reductive environment conducive to Cu precipitation at medium temperatures (255°C-342°C). Al-Si and Fe-Mg substitutions were found to be the primary processes involved in its generation. Additionally, from the mineralisation centre outwards, there was an observed decrease in Si content as well as the Fe/(Fe+Mg) ratio in H-type chlorite, along with decreases in temperature, sulphur, and oxygen fugacity of allchlorites; conversely, increases were observed for Al content along with Mg and Mn elements in H-type chlorite. Chlorite is useful for exploring porphyry copper systems as an indicator mineral. [ABSTRACT FROM AUTHOR]

The classification system and the higher level phylogenetic relationships of Pentatomomorpha, the second largest infraorder of Heteroptera (Insecta: Hemiptera), have been debated and remain controversial over decades. In particular, the placement and phylogenetic relationship of Idiostoloidea are not well resolved, which hampers a better understanding of the evolutionary history of Pentatomomorpha. In this study, for the first time, we reported the complete mitochondrial genome for two narrowly distributed families of Idiostoloidea (including Idiostolidae and Henicocoridae), respectively. The length of the mitochondrial genome of Monteithocoris hirsutus and Henicocoris sp. is 16,632 and 16,013 bp, respectively. The content of AT is ranging from 75.15% to 80.48%. The mitogenomic structure of Idiostoloidea is highly conservative and there are no gene arrangements. By using the Bayesian inference, maximum likelihood, and Bayesian site‐heterogeneous mixture model, we inferred the phylogenetic relationships within Pentatomomorpha and estimated their divergence times based on concatenated mitogenomes and nuclear ribosomal genes. Our results support the classification system of six superfamilies within Pentatomomorpha and confirm the monophyletic groups of each superfamily, with the following phylogenetic relationships: (Aradoidea + (Pentatomoidea + (Idiostoloidea + (Coreoidea + (Pyrrhocoroidea + Lygaeoidea))))). Furthermore, estimated divergence times revealed that most pentatomomorphan superfamilies and families diverged during the Late Jurassic to Early Cretaceous, which coincides with the explosive radiation of angiosperms. [ABSTRACT FROM AUTHOR]

C15H16N5O5Cl, monoclinic, P21/n (no. 14), a = 7.37210(10) Å, b = 13.30639(19) Å, c = 17.1682(2) Å, β = 97.2301(12)°, Z = 4, V = 1670.74(4) Å3, Rgt(F) = 0.0357, wRref(F2) = 0.1023, T = 173(1) K.

A reconfigurable transmission metasurfaces (RTMs) excited by a multiple‐input multiple‐output (MIMO)(RTMs‐MIMO) antenna is designed to implement multi‐domain metamaterial computational imaging (MCI). Based on the receiver‐transmitter metasurfaces structure, four PIN diodes are applied to control the operating state of the RTMs. It enables arbitrary switching among four polarization transmission waves. A reverse‐induced current can be generated by adjusting the PIN diodes in the symmetrical position, resulting in a perfect 1‐bit phase modulation with a 3dB‐loss bandwidth of 15.38~19.89 GHz. A microstrip antenna with mushroom‐shaped parasitic patches is employed to implement the MIMO feeds. The ‐10dB bandwidth of MIMO antenna is compatible with the RTMs, and the maximum envelope correlation coefficient of 0.16 demonstrates good isolation between the MIMO feeds. In the MCI system constructed by the RTMs‐MIMO antennas, a transmission matrix H can be achieved by MIMO space beams, metasurfaces phase, metasurfaces polarization, and frequency modes. The correlation coefficient µg = 0.018 is achieved by the multi‐domain integration, allowing H to be highly non‐correlated. Based on the detection results of H, an imaging result with a relative reconstruction error of 0.372 is achieved. The designed MCI system therefore has unparalleled application prospects in the broad field of medical and military detection. [ABSTRACT FROM AUTHOR]

[Purpose/significance] This research explores the relationship between the health information search behaviors of college students and the spatiotemporal situation of public health emergencies, in order to reveal the coupling characteristics of users' health information search behaviors and public health emergencies. [Method/process] Using mobile experience sampling method and key event method to collect 380 college students’ health information search diary data as research samples, the process of user information search (information sources selection, information search patterns) and results (information utilization methods, health awareness and emotional perception) in public health emergencies were the entry points, and spatiotemporal characteristics of health information search in the context of public health events of college students were statistically analyzed. [Result/conclusion] The spatiotemporal coupling characteristics of user health information search results of college students in public health emergencies are obvious. The combined using way of health information search and changes in health consciousness of college students both show significant differences in time and space distribution. In the outbreak period and high-risk areas, users prefer to sharing information offline while self-use, and the level of health awareness changes is relatively high. In the duration period and low and medium risk areas, users prefer to share online while self-use, and the level of health awareness changes is relatively low. Although the single using way of information and emotional perception do not show significant differences in time and space distribution, the single using way of information spatiotemporal coupling characteristics are still reflected in descriptive data. The search process of college students' health information shows normalized features such as users' habitual use of mobile devices as information sources and preference information encounters. This research reveals the spatiotemporal contextual characteristics of health information search behaviors in emergencies, which helps the information service department in-depth grasp the law of information behavior changes in different periods and regions of public health emergencies and improve accurate information services level.

The determination of the aflatoxin B1 (AFB1) content has received widespread attention in the context of food safety, which is a global public health issue. Accordingly, a label-free and turn-on fluorescent AFB1 determination method is developed herein with an ss-DNA aptamer as the recognition element, 4, 4-(1E,1E)-2, 2-(anthracene-9, 10-diyl) bis(ethene-2, 1-diyl) bis(N, N, N-trimethylbenzenaminium iodide) (DSAI) as the aggregation-induced emission (AIE) fluorescent probe, and single-walled carbon nanohorns (SWCNHs) as the selective part with a fluorescence quenching effect. In the presence of AFB1, the AFB1-specific aptamer undergoes a structural transformation and switches from being a random helix to a folded structure. DSAI's fluorescence is protected as a result of the resistance of the transformed aptamer adsorbed on the SWCNHs' surface. Because DSAI's fluorescence is not quenchable, the fluorescence intensity is calculated as a function of the AFB1 concentration. By simply mixing DSAI, aptamer, AFB1 samples, and SWCNHs, the method can be carried out in 2 h, with a limit of detection (LOD) of 1.83 ng/mL. It has a high selectivity in the presence of other mycotoxins, and its performance is confirmed in soybean sauce with a known concentration of AFB1. The LOD was 1.92 ng/mL in the soy sauce samples and the recovery ranged from 95 to 106%, implying that the presented aptasensor has great potential for food analysis. [ABSTRACT FROM AUTHOR]