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The electronic and nonlinear optical (NLO) properties of Al13–X and 2Al13–X (where X represents dianhydrides BPDA, BTDA, ODPA, and 6FDA) were systematically investigated using (time-dependent) density functional theory methods. It was found that Al13 could effectively bind to dianhydride molecules via two strong Al–O bonds with high binding energies. Compared to pristine Al13 and dianhydrides, hybridized complexes Al13–X exhibit significant enhancements in both linear and nonlinear optical response properties, as evidenced by the calculated isotropic polarizability and static/dynamic first hyperpolarizabilities, respectively. The nature of the large first hyperpolarizabilities of Al13–X complexes can be understood by analyzing the low excitation energies of the key excited states and the first hyperpolarizability density. Furthermore, the dianhydride ligand is capable of bridging two aluminum clusters to form a novel D–A–D molecule, which further enhances the NLO properties of the molecules. It is hoped that the current research work will provide ideas for the rational design of such inorganic–organic hybrid complexes as novel functional electro-optical materials. [ABSTRACT FROM AUTHOR]

The Yolov4 detection algorithm does not sufficiently extract local semantic and location information. This study aims to solve this problem by proposing a Yolov4-based multiscale feature fusion detection system for high-speed train wheel tread defects. First, multiscale feature maps are obtained from a feature extraction backbone network. The proposed multiscale feature fusion network then fuses the underlying features of the original three scales. These fused features contain more defect semantic information and location details. Based on the fused features, a path aggregation network is used to fuse feature maps at different resolutions, with an improved loss function that speeds up the convergence of the network. Experimental results show that the proposed method is effective at detecting defects in the wheel treads of high-speed trains., Author(s): Changfan Zhang [1]; Xinliang Hu [2]; Jing He (corresponding author) [1]; Na Hou [1] 1. Introduction High-speed train fault diagnosis is crucial for the safe operation and maintenance of [...]

Purposes To explore the teaching effect and value of virtual reality technology combined with PBL teaching method applied to sports anatomy.Procedures 119 undergraduate students majoring in physical education of Xianyang Normal University were selected as research objects.Randomly divided into experimental group (N=59) and control group (N=60).Methods The experimental group used virtual reality technology combined with PBL teaching method, and the control group used traditional teaching method to teach. At the end of the course, the test scores of the two groups and the evaluation results of self-learning effect were statistically analyzed. Results the test scores of the students in the experimental group were significantly higher than those in the control group (P

This article discusses the synthesis of ynamides, a class of N-alkynyl compounds, through various catalytic reactions. The authors highlight the importance of ynamides in the synthesis of nitrogen-containing scaffolds and summarize existing methods for their synthesis. They also present their own research on the direct catalytic addition of terminal alkynes to azodicarboxylates to produce ynehydrazides, which can then be converted into ynamides. The authors propose potential future directions for further research in this field. [Extracted from the article]

Countries with different democratic levels tend to show various degrees of emphasis on military expenditure and a consensus can hardly be reached on the economic effect of democracy and military expenditure. By applying a panel vector autoregressive (PVAR) approach, this article examines the potential dynamic and endogenous relationships among democracy, military expenditure and economic growth of 126 countries from 1990 to 2020. Furthermore, the k-means clustering algorithm is employed to account for the heterogeneous interaction between democracy and military expenditure in different countries. The empirical results reveal that the strong positive impact of democracy and the negative effect of military spending on economic growth exists in the full sample and the cluster of countries with low democratic levels and a high military burden. For democratic countries with low military expenditure, there is a more significant and negative impact both of military expenditure on democracy and vice versa. [ABSTRACT FROM AUTHOR]

With the advent of smart cities, the significance of the Internet of Things (IoT) is gaining greater prominence. At the same time, the safety early warning system in the IoT has a significant impact on real-time monitoring and the response to potential risks. Despite the advancements made in edge-assisted IoT deployments, several challenges and constraints persist. Given the potential threat to life posed by safety-related messages, ensuring the authenticity of messages in the edge-assisted IoT safety warning system is crucial. However, considering the identity privacy of devices participating in the edge-assisted Internet of Things system, directly verifying the identity of the sending device is undesirable. To address this issue, in this work, we design a linkable group signature scheme that allows devices to anonymously send safety-related messages to edge nodes, defending against Sybil attacks while ensuring the traceability of malicious device identities. Then, we present a high-efficiency conditional privacy-preserving authentication (CPPA) scheme based on the designed group signatures for the safety warning system in edge-assisted IoT. This scheme effectively protects device identity privacy while providing a reliable authentication mechanism to ensure the credibility and traceability of alert messages. The proposed scheme contributes to the field of safety warning systems in the context of edge-assisted IoT, providing a robust solution for privacy preservation and authentication. [ABSTRACT FROM AUTHOR]

The challenging issues in infrared and visible image fusion (IVIF) are extracting and fusing as much useful information as possible contained in the source images, namely, the rich textures in visible images and the significant contrast in infrared images. Existing fusion methods cannot address this problem well due to the handcrafted fusion operations and the extraction of features only from a single scale. In this work, we solve the problems of insufficient information extraction and fusion from another perspective to overcome the difficulties in lacking textures and unhighlighted targets in fused images. We propose a multi-scale feature extraction (MFE) and joint attention fusion (JAF) based end-to-end method using a generative adversarial network (MJ-GAN) framework for the aim of IVIF. The MFE modules are embedded in the two-stream structure-based generator in a densely connected manner to comprehensively extract multi-grained deep features from the source image pairs and reuse them during reconstruction. Moreover, an improved self-attention structure is introduced into the MFEs to enhance the pertinence among multi-grained features. The merging procedure for salient and important features is conducted via the JAF network in a feature recalibration manner, which also produces the fused image in a reasonable manner. Eventually, we can reconstruct a primary fused image with the major infrared radiometric information and a small amount of visible texture information via a single decoder network. The dual discriminator with strong discriminative power can add more texture and contrast information to the final fused image. Extensive experiments on four publicly available datasets show that the proposed method ultimately achieves phenomenal performance in both visual quality and quantitative assessment compared with nine leading algorithms. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) has been carried out to investigate the electronic characteristics, UV–VIS–NIR absorption spectra, and nonlinear optical (NLO) properties of two series of zinc porphyrin analogs (FPD‐Nx and TPD‐Nx, x = 0–4) with donor‐π‐donor frameworks. The design of these analogs is based on previously synthesized furan‐linked zinc porphyrins (FPDs) and thiophene‐linked zinc porphyrins (TPDs). It is noted that their electro‐optical features are sensitive to the numbers of N‐coordination atoms and the attached groups. A dramatic enhancement of static first and second hyperpolarizabilities (β0 and γ0) occurs when two furan/thiophene rings are attached to the zinc porphyrin. Among the two series, FPD‐N3 and TPD‐N3 have the largest β0 values of about 7600 a.u. The static γ0 values of these complexes range from 0.41 × 106 to 1.79 × 106 a.u. The FPD‐Nx has a larger γ0 value than the corresponding TPD‐Nx, but the γ0 value of FPD‐N2 is close to that of TPD‐N2. In the dynamic NLO process, the electro‐optical Pockels effect, second harmonic generation, and electro‐optic Kerr effect can be enhanced at the wavelength of 1907 nm. This study provides a new strategy for the experimental design of high‐performance NLO materials. [ABSTRACT FROM AUTHOR]

The electronic and second‐order nonlinear optical (NLO) properties of small Agn clusters (n = 1 to 3) doped graphyne (GY) and pyrazine‐modified graphyne (pyGY) have been investigated employing (time‐dependent) density functional theory calculations. A large triangular hole of GY provides an efficient site to accommodate the Agn cluster, and an Ag atom prefers to be located in the center of the pyGY, interacting with the two pyridine N atoms. The silver clusters have strong interactions with GY/pyGY, and the intramolecular charge transfer is significant for determining NLO properties. The first hyperpolarizability (β0) values can be modulated by the introduction of silver clusters. The results show that the second‐order NLO response of Ag2/Ag3 doped pyGY complex is stronger than that of corresponding Ag2/Ag3 doped GY complex, while the β0 for single Ag doped GY is significantly higher than that of Ag@pyGY. Hence, the NLO responses of these complexes depend on the size of the clusters and the type of nanosheets. All complexes exhibit excellent transparency in the deep ultraviolet region, especially Ag3@GY/pyGY. These results suggest that these Agn clusters doped GY/pyGY are excellent candidates for potential applications in optical devices. [ABSTRACT FROM AUTHOR]

Juglandaceae (walnut) is made up of several economically and ecologically valuable tree species. Chloroplasts, vitally important for plant growth, are also a rich source of genetic and evolutionary information. Both mutational pressure and natural selection are drivers of codon usage pattern variation among genes. Here, we studied the codon usage of Juglandaceae chloroplast genomes in order to further our understanding of the biology and evolution of this plant family. The codon usage patterns associated with the chloroplast genomes of 26 Juglandaceae samples were analyzed. Short CDS sequences (<100 amino acids) and sequencing containing internal stop codons were removed from comparative analyses. The contents of uracil (U) (31.5%–32.0%) and adenine (A) (30.0%–31.2%) of all 26 samples were higher than those of cytosine (C) (17.2%–17.7%) and guanine (G) 19.9%–20.7%. According to the neutrality and correspondence analyses, chloroplast codons tended to exhibit conserved GC content and were primarily altered by natural selection. The parity rule 2 plot analysis revealed that AU were more common than GC at the third-codon position. According to the effective number of codon (ENC) plot analysis, codon preference was driven by natural selection and protein translation, among other factors. This study represents the first examination of the codon usage characteristics of Juglandaceae plants, as revealed through the study of codon bias in 26 Juglandaceae samples. [ABSTRACT FROM AUTHOR]

The electronic and nonlinear optical (NLO) properties of Al13-TCNQ/F4-TCNQ were systematically investigated using density functional theory methods. The Al13-TCNQ/F4-TCNQ complex has a high ionization potential of 7.51/6.71 eV and a strong binding energy of 1.93/2.39 eV, indicating its high structural stability. The stability of the complexes is confirmed through atom-centered density matrix propagation simulation at different temperatures up to 2000 fs. TCNQ/F4-TCNQ (electron donor) interacts with Al13 to form a charge-transfer framework, and F4-TCNQ is a stronger electron acceptor. A113-TCNQ and A113-F4-TCNQ complexes exhibit excellent NLO responses [static first and second hyperpolarizability (β0 and γ0), hyper-Rayleigh scattering coefficient (βHRS), frequency-dependent first hyperpolarizability β(−2ω; ω, ω) and β(−ω; ω, 0)], which are crucial evaluation indexes for designing NLO materials. The static and dynamic hyperpolarizability increases with the enhancement of the electron-acceptor capacity, for example, the β0 value of Al13-F4-TCNQ (92 275 au) is larger than that of Al13-TCNQ (76 720 au). The absorption spectrum reveals that these molecules have deep ultraviolet (UV) and infrared (IR) transparent regions, and hence are new UV and IR NLO molecules. Therefore, linking an Al13 cluster with TCNQ/F4-TCNQ is an effective strategy to design stable potential candidates for high-performance NLO molecules. [ABSTRACT FROM AUTHOR]

Based on the donor‐acceptor framework of graphdiyne–triphenylamine (GDY–TPA), eight GDY–π–TPA molecules were designed by introducing a π‐conjugated bridge, including electron‐rich heterocycles, electron‐deficient heterocycles, and unsaturated hydrocarbons. The geometric structures, electronic characteristics, static nonlinear optical (NLO) properties, and frequency‐dependent HRS first hyperpolarizabilities were investigated employing the density functional theory (DFT) calculations. The charge population analysis reveals that electron‐rich heterocyclics and unsaturated hydrocarbons act as donors, whereas electron‐deficient heterocyclics can be regarded as acceptors, significantly increasing the first hyperpolarizabilities (β0) of GDY–π–TPA (except for B‐3). The C‐1 compound containing the vinyl unit is the best NLO model among all systems. The nature of the excellent NLO properties of the systems can be understood from the low excitation energy of the crucial excited state and the analysis of the first hyperpolarizability density. In addition, the varying order of static and dynamic βHRS values is consistent with those of β0 values. Understanding the relationship between structure and nonlinear optical response can provide guidance for the theoretical design of NLO molecules. [ABSTRACT FROM AUTHOR]

This paper examines the demand for military expenditure in eighteen selected Indo-Pacific countries for the years 1993–2018. As the dominant powers, the U.S. and China characterize the geopolitical structure of the Indo-Pacific region. Sino-U.S. relations are newly quantified by measuring the number of cooperative and conflict events between China and the United States based on the Global Database of Events, Language, and Tone (GDELT). After incorporating Sino-U.S. relation variables into neoclassical demand models, the panel data estimating results reveal that the increasing number of confrontations from the United States toward China has lead to increases in non-U.S. allies' military expenditure while the rise in China confronting the United States has not. U.S. allies in the Indo-Pacific region have tended to increase military expenditure when the United States increases its pressure on China. The empirical results provide evidence that Sino-U.S. relations affect the level of military expenditure in the Indo-Pacific Region. [ABSTRACT FROM AUTHOR]

The YABBY gene family is a plant transcription factor that exists in all seed plants. YABBY family members have been studied extensively in various plants and were to play significant roles in plant growth and development. Juglans, especially walnuts, are important economic tree species that are widely distributed worldwide. However, the identification and related research of YABBY in Juglans have not been reported to date. In this study, we identified 19 YABBY genes from two Juglans species, namely, J. regia and J. mandshurica. Ten JrYABBY genes and nine JmYABBY genes were divided into five subfamilies (YAB1/3, YAB2, INO, CRC, and YAB5). Sequence analysis revealed that all encoded YABBY protein sequences had a highly conserved YABBY and C2C2 zinc-finger domains. An analysis of the assumed cis-acting elements revealed that JrYABBY and JmYABBY genes were deeply involved in phytohormone and light responses. Further, gene expression pattern analysis suggested that most walnut YABBY genes were likely involved in peel and flower development and responses to biotic stress. This study not only suppled novel insights into the evolutionary basis of YABBY gene families in Juglans, but also provided clues for the further functional verification and investigation of YABBY genes in other tree species. [ABSTRACT FROM AUTHOR]

Hickory (Carya cathayensis) kernel is rich in powerful bioactive flavonoids, which can remove excess free radicals in the human body and play an important role in regulating the physiological metabolism of the plant. This study investigated the changes of flavonoids in hickory exocarp and embryo during development. In this study, 72 DEGs involved in the regulation of flavonoid biosynthesis in fruits were identified, and TT4 , CCoAOMT1 , UGT71D1 , C4H , F3H , TT8 , FLS1 , and LDOX were identified as the core genes of flavonoid biosynthesis. A total of 144 flavonoid-related metabolites were detected by metabolite analysis. Transcriptome and metabolome analysis combined to construct the flavonoid biosynthesis regulatory pathway in the development stage of hickory fruit. Our results provide a theoretical basis for the exploration and regulation of functional genes related to flavonoid biosynthesis and metabolism in hickory and other plants and the breeding of new walnut varieties. [ABSTRACT FROM AUTHOR]

Circular RNA LDLRAD3 behaved as an oncogene in several malignancies, but its effects in NSCLC and the involvement of downstream molecules and activation of signaling pathways had not been fully reported. We planned to explore how LDLRAD3 facilitated the malignancy of NSCLC. QRT-PCR was performed to evaluate the expression levels of LDLRAD3, miR-20a-5p, and SLC7A5 in NSCLC tissues and cells. si-LDLRAD3 was transfected to A549 and H1299 cells to knock down intrinsic LDLRAD3 to determine its oncogenic roles. CCK-8 assay and transwell assay were executed to assess cell proliferative, migrative, and invasive abilities. Dual-luciferase reporter (DLR) assay was manipulated to verify the ENCORI-predicted relationships between LDLRAD3 and miR-20a-5p and between miR-20a-5p and SLC7A5. Western blot, immunofluorescent assay, and immunohistochemistry were applied to explore the expression levels of SLC7A5, and the levels of mTORC1 pathway-related proteins were evaluated using western blot. Rescue experiments were conducted by transfecting si-LDLRAD3, miR-20a-5p inhibitor, and si-SLC7A5 to explore the influence of the LDLRAD3-miR-20a-5p-SLC7A5 axis on the malignant behaviors of NSCLC cells. The expression levels of LDLRAD3 and SLC7A5 were boosted, whereas miR-20a-5p was impeded in NSCLC tissues and cell lines. Knockdown of LDLRAD3 weakened the proliferation, migration, and invasion of A549 and H1299 cells. LDLRAD3 was verified to sponge miR-20a-5p and miR-20a-5p targeted SLC7A5. LDLRAD3 activated the mTORC1 singling pathway via the miR-20a-5p-SLC7A5 axis to strengthen the malignant properties of A549 and H1299 cells. We concluded that LDLRAD3 exerted oncogenic effects via the miR-20a-5p-SLC7A5 axis to activate the mTORC1 signaling pathway in NSCLC. Our findings enlightened that LDLRAD3 could become a potential therapeutic target in the treatment and management of NSCLC. [ABSTRACT FROM AUTHOR]

The article features the operation of medical solutions provider LinkDoc, which uses artificial intelligence (AI) in providing solutions to issues on online diagnoses and treatments confronted by doctors. Also cited are how LinkDoc was spun off by parent firm Xinshi Technology and the grade venture capital investment of 10 million renminbi from venture capitalist New Enterprise Associates, Inc. (NEA).

Using density functional theory calculations, we have analyzed second‐order nonlinear optical (NLO) properties of a series of −(CH=CH)m−NH2/NO2‐modified graphynes (GY[n]) (n=1−3; m=1−6, 9, 12). This type of modification can induce evident electron transfer between the graphyne and conjugated chain and decrease the transition energy, resulting in the system exhibiting a large static first hyperpolarizability (β0). The β0 values of the GY[n]−(CH=CH)m−NH2/NO2 show a monotonously increasing trend with lengthening the −(CH=CH)m−NH2/NO2 chain from m=1 to 12. Further, the NO2‐modified system has a higher β0 value than the corresponding NH2‐modified system with the same π‐conjugated length. Compared with the single‐modified GY[1], the −(CH=CH)m−NH2/NO2 co‐modified GY[1] systems exhibit better NLO responses. For GY[n]−(CH=CH)m−NO2, when m=1−4, the β0 value increases with increasing the size of graphyne, while for m=5, 6, 9, 12, the varying order is reversed. Solvent and frequency dispersion effects are also analyzed. The polarizable environment has a significant influence on hyper‐Rayleigh scattering first hyperpolarizability (βHRS). [ABSTRACT FROM AUTHOR]

Two novel complexes were constructed by adsorption of two typical organic molecules, including one electron-donating molecule (TTF = tetrathiafulvalene) and one electron-withdrawing molecule (TCNQ = tetracyanoquinodimethane), on the surface of black phosphorus quantum dots (BPQDs). There exist considerable charge transfer and strong non-covalent interaction between organic molecules and BPQDs. The results of density functional theory (DFT) calculations show that the static first and second hyperpolarizabilities can be significantly enhanced by introducing TTF/TCNQ groups on BPQDs. Apart from static nonlinearity, hyper-Rayleigh scattering (HRS) first hyperpolarizability shows a remarkable value at a dispersion frequency of 1907 nm. Besides, the frequency-dependent first hyperpolarizability increases significantly while going from the gas to solvent phase. BPQDs–TTF presents a strong dipolar character, whereas BPQDs–TCNQ presents a relatively larger octupolar behavior. Compared with BPQDs–TTF, BPQDs–TCNQ exhibits better stability and larger first hyperpolarizability. This work highlights the superiority of combining TCNQ and BPQDs to construct high-performance nonlinear optical (NLO) molecules. [ABSTRACT FROM AUTHOR]

Abstract Background Since 2008, a progressive pneumonia has become prevalent in broilers and laying hens. This disease occurrs the first day after hatching and lasts more than 30 days, resulting in approximately 70% morbidity and 30% mortality in broilers. The objective of this study was to isolate and identify the pathogens that are responsible for the progressive pneumonia and establish an animal model for drug screening. Results 193 serum samples were collected from 8 intensive farms from 5 provinces in China and analysed in the current research. Our clinical survey showed that 65.2% to 100% of breeding broilers, breeding layers, broilers and laying hens were seropositive for ORT antibodies. From 8 intensive farms, six ORT isolates were identified by PCR and biochemical assays, and two H9N2 viruses were isolated. Newcastle Disease Virus (NDV) and Infectious BronchitisVirus (IBV) were excluded. Typical pneumonia and airsacculitis were observed both in broilers inoculated intraperitoneally with an ORT isolate alone and in those co-infected with ORT and H9N2 virus isolates. Specifically, the survival rate was 30%, 20%, 70%, 50% and 90% in birds inoculated with ORT+H9N2 virus, ORT followed by H9N2 virus, H9N2 virus followed by ORT, and ORT or H9N2 virus alone, respectively. Conclusions The results of this study suggest that ORT infections of domestic poultry have been occurring frequently in China. ORT infection can induce higher economic losses and mortality if H9N2 AIV is also present. Although the isolation of ORT and H9N2 virus has been reported previously, there have been no reported co-infections of poultry with these two pathogens. This is the first report of co-infection of broilers with ORT and H9N2 virus, and this co-infection is probably associated with the outbreak of broiler airsacculitis in China, which has caused extensive economic losses.

Based on the combination of novel carbon material graphynes (GYs) and superalkalis (OM3), a class of GY superalkali complexes, OM3+@(GY/GDY/GTY)− (M = Li, Na, and K), has been designed and investigated using the density functional theory method. Computational results reveal that these complexes with high stability can be regarded as novel superalkali salts of GYs due to electron transfer from OM3 to GYs. For second‐order nonlinear optical response, these superalkali salts exhibit large first hyperpolarizabilities (β0). Two essential effects on β0 values are found, namely, the atomic number of alkali atom in superalkali and the pore size of GY. Integrating the two effects, the selected combination of OLi3 with large pore size graphtrigne (GTY) can lead to a considerable β0 value (6.5 × 105 au), which is a new record for superatom‐doped GYs. In the resulting complex, the OLi3 unit is located at the center of the pore of GTY, forming a planar structure with the highest stability among these salts. Besides large β0 values, these superalkali salts of GYs have a deep‐ultraviolet working region; hence, they can be considered a kind of high‐performance deep‐ultraviolet NLO molecule. [ABSTRACT FROM AUTHOR]

Background: Alzheimer's disease (AD) and Parkinson's disease (PD) are two major neurodegenerative diseases worldwide. Demographic aging is in rapid progress in China. Up-to-date estimates of AD and PD prevalence have not been provided. Methods: Studies that reported the prevalence of AD and PD in China were identified via a systematic database search from 1985 to 2018. Meta-analysis, local polynomial regression and autoregressive integrated moving average model were used for analyses. Results: A total of 99 studies were included in the study with populations of 385,312 and 227,228, respectively for AD and PD. The overall prevalence of AD and PD following age standardization was 3.20% [95% confidence interval (CI) = 3.17–3.23] and 1.06% (95% CI = 1.02–1.10), respectively in individuals over 60 years old. The rates increased drastically for every 10-years increment of age. The yearly prevalence of AD was predicted to increase from 3.81 to 6.17% in the next 5 years. Significant differences were observed between genders [male to female odds ratio (OR) for AD = 0.57, 95% CI = 0.51–0.64; OR for PD = 1.25, 95% CI = 1.06–1.46], and between education levels (Illiterate to non-illiterate OR for AD = 2.99, 95% CI = 2.38–3.75), but not between urban and rural settings. Conclusion: Our results provide an updated insight into the epidemiology of AD and PD in China and their associated rates and ratios. The findings may facilitate China policy makers and health professionals mitigate the related health issues. [ABSTRACT FROM AUTHOR]

Southwestern (SW) China is an area of active tectonism and erosion, yielding a dynamic, deeply eroded landscape that influences the genetic structure of the resident populations of plants and animals. Iron walnut (Juglans regia subsp. sigillata) is a deciduous tree species endemic to this region of China and cultivated there for its edible nuts. We sampled 36 iron walnut populations from locations throughout the species' range in SW China and genotyped a total of 765 individuals at five chloroplast DNA regions and 22 nuclear microsatellite loci. Species distribution models were produced to predict the evolution and historical biogeography of iron walnut and to estimate the impacts of climate oscillations and orographic environments on the species' demography. Our results indicated that J. regia subsp. sigillata had relatively low genetic diversity, high interpopulation genetic differentiation, and asymmetric interpopulation gene flow. Based on DIYABC analysis, we identified two lineages of J. sigillata in southwestern China. The lineages (subpopulations) diverge during the last glacial period (~1.34 Ma). Southwestern China was a glacial refuge during the last glacial period, but increasingly colder and arid climates might have fostered the fragmentation of J. regia subsp. sigillata within this refugium. Finally, we found that recent habitat fragmentation has led to a reduction in population connectivity and increased genetic differentiation by genetic drift in isolated populations. Our results support a conclusion that geological and climatic factors since the Miocene triggered the differentiation, evolutionary origin, and range shifts of J. sigillata in the studied region. [ABSTRACT FROM AUTHOR]

Cancer is a main reason for human morbidity and mortality globally. Screening and identifying new anticancer chemical substances is considered as a valid treatment for carcinoma. In our study on synthesis and search towards the development of potential anticancer agents, a series of thieno[2,3‐d]pyrimidine derivatives were prepared from the functionalized iminophosphorane via aza‐Wittig reaction. Their structures were confirmed by 1H NMR, 13C NMR, MS and elemental analysis. The in vitro antitumor activities of compounds were analyzed with CCK8 standard method. It revealed these thieno[2,3‐d]pyrimidine derivatives were exhibited cytotoxicity against HepG2, HEp‐2, and MCF‐7 cell lines. The most potent compounds, 5 h and 5 j, were efficacious against HEp‐2 cells with IC50 1.8μmol/L and 0.8μmol/L, respectively. Meanwhile, 5 a, 5 d and 5 h showed broad spectrum of cytotoxicity for HepG2, Hep2 and MCF‐7 three different cell lines with IC50 range of 1.8‐87.5μmol/L. Furthermore, we demonstrated that cytotoxicity of 5 j was due to the activation of caspase‐9 involved apoptotic pathway, which is death receptor independent. [ABSTRACT FROM AUTHOR]

Abstract Based on the density functional theory calculations, the BP-(B 3 N 3) n and Li@BP-(B 3 N 3) n (BP = biphenylene, n = 1–4) systems, were designed for the first time and explored the effects of Li doping and B 3 N 3 substitution on their nonlinear optical (NLO) properties. We find that, when the carbon rings are replaced by B 3 N 3 units in the biphenylene, systems of enhanced static hyperpolarizabilities (β 0) are delivered. And the position and the number of B 3 N 3 unit have an important effect on the β 0 value. Moreover, when one Li atom is adsorbed on the surface of B 3 N 3 -substituted BP, the β 0 values of these systems are further dramatically enhanced to 2.24 × 104–1.42 × 106 au. The further investigations show that small transition energy is the decisive factor for their large β 0 values. Specially, these Li-doped compounds exhibits high stability and excellent infrared (IR) transparency. These findings might provide valuable insights into the design of novel high-performance NLO materials based on BP flake. Highlights • The position and the number of B 3 N 3 unit have large influence on β 0 of BP-(B 3 N 3) n. • Li atom can further enhance the NLO response of the B 3 N 3 -substituted biphenylene. • The β 0 values of Li@BP-(B 3 N 3) n are much larger than those of Li@BP systems. • Absorption spectra shows that Li-doped molecules can be used as IR NLO materials. [ABSTRACT FROM AUTHOR]