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Multiple SARS-CoV-2 variants of concern (VOCs) have been emerging and some have been linked to an increase in case numbers globally. However, there is yet a lack of understanding of the molecular basis for the interactions between the human ACE2 (hACE2) receptor and these VOCs. Here we examined several VOCs including Alpha, Beta, and Gamma, and demonstrate that five variants receptor-binding domain (RBD) increased binding affinity for hACE2, and four variants pseudoviruses increased entry into susceptible cells. Crystal structures of hACE2-RBD complexes help identify the key residues facilitating changes in hACE2 binding affinity. Additionally, soluble hACE2 protein efficiently prevent most of the variants pseudoviruses. Our findings provide important molecular information and may help the development of novel therapeutic and prophylactic agents targeting these emerging mutants., The SARS-CoV-2 spike (S) protein mediates viral entry by binding of its receptor-binding domain (RBD) to the human angiotensin-converting enzyme 2 (ACE2) receptor and mutations of the S protein may have a great impact on virus transmissibility. Here, the authors characterize the interactions of six different SARS-CoV-2 RBD variants among them Alpha, Beta and Gamma and present crystal structures of these ACE2-RBD complexes.

Based on the deformation and damage characteristics of the surrounding rock in a large-section gob-side entry retaining and combined with field observations and an analysis of the dominant factors, an overall deformation control plan is formulated. The plan mainly includes a structure of high strength, high stiffness and high ductility for roadside support; the reinforcement of the roadway-in support; and the setup entry hydraulic fracturing pressure release mechanism and advanced long, horizontal borehole “fracturing-jet” pressure relief technology. Industrial field tests were completed taking Tangan coal mine as the engineering background. The research shows that the large-section gob-side entry retaining has the typical “asymmetric” overall deformation and damage characteristics, including top coal sinking along the inner side of the roadside support, the whole roadside support structure skewing, and even splitting damage; floor heaving; and the coal-side bolt support structure basically losing support ability and bulging out from the coal side. The dominant factors of deformation damage are disintegration of the floor mudstone by water and deflection deformation under horizontal stress, splitting damage in the concrete roadside support under asymmetric load, damage and expansion due to the insufficient strength of the coal side support, strong dynamic pressure on the roof, and the mutual influence of support and pressure relief. The industrial test shows that the deformation control scheme optimizes the stress environment of the gob-side entry retaining space, the deformation control effect is remarkable, and the roadside fully meets the reuse requirements.

Twitter is one of the most popular social networking platforms today with nearly 238 million active daily users. While the platform is used by a myriad of individuals for various purposes, businesses both large and small have begun to adopt Twitter into their business strategy to better connect with consumers. Considering the growing emphasis on social media engagement in the business sector, the present study examines some of the fastest-growing American small businesses from the perspective of media events theory. According to media events theory, certain large-scale events will attract excess viewership and attention from the public, both on traditional and digital platforms. We examine how small businesses leveraged media events of 2020, including COVID-19 and the 2020 US presidential election, so as to increase engagement and foster the growth of their businesses via Twitter. Using 35000 tweets based on media event-related hashtags collected throughout 2020, we investigated Twitter engagement among 100 of the fastest-growing small businesses in the USA. Through the use of network analysis metrics, we illustrate that businesses that tweeted about media events often received greater levels of user engagement and exerted greater influence over their respective networks.

Bat-origin RshSTT182 and RshSTT200 coronaviruses (CoV) from Rhinolophus shameli in Southeast Asia (Cambodia) share 92.6% whole-genome identity with SARS-CoV-2 and show identical receptor-binding domains (RBDs). In this study, we determined the structure of the RshSTT182/200 receptor binding domain (RBD) in complex with human angiotensin-converting enzyme 2 (hACE2) and identified the key residues that influence receptor binding. The binding of the RshSTT182/200 RBD to ACE2 orthologs from 39 animal species, including 18 bat species, was used to evaluate its host range. The RshSTT182/200 RBD broadly recognized 21 of 39 ACE2 orthologs, although its binding affinities for the orthologs were weaker than those of the RBD of SARS-CoV-2. Furthermore, RshSTT182 pseudovirus could utilize human, fox, and Rhinolophus affinis ACE2 receptors for cell entry. Moreover, we found that SARS-CoV-2 induces cross-neutralizing antibodies against RshSTT182 pseudovirus. Taken together, these findings indicate that RshSTT182/200 can potentially infect susceptible animals, but requires further evolution to obtain strong interspecies transmission abilities like SARS-CoV-2.

Background To review our long-term clinical experience, analyze the failure patterns, and give suggestions for target volume delineation of carcinoma showing thymus-like differentiation (CASTLE) treated with intensity-modulated radiotherapy (IMRT). Methods From April 2008 to May 2019, 30 patients with CASTLE treated by postoperative or radical IMRT in our center were retrospectively reviewed. A total dose of 56-60 Gy in 28–30 fractions was prescribed to patients without residual disease and 66 Gy in 33 fractions for patients with residual or unresectable disease. Survival rates were calculated using the Kaplan-Meier method. Treatment-related toxicities were graded by National Cancer Institute Common Toxicity Criteria (NCI-CTC) version 4.0. Results Among the 30 patients, 12 (40%) received partial resection or biopsy. Lateral lymph node metastasis was observed in 7 (23.3%) patients. During follow-up, regional lymph node recurrence occurred in 2 patients and distant metastasis in 5 patients. With a median follow-up time of 63.5 months, the 5-year local recurrence-free survival (LRFS), regional recurrence-free survival (RRFS), distant metastasis-free survival (DMFS), overall survival (OS) and progression-free survival (PFS) rates were 100, 88.9, 78.9, 93.1 and 78.9%, respectively. For patients with no lateral neck node metastasis, prophylactic radiotherapy for lateral neck nodal regions failed to improve RRFS (p = 0.381) and OS (p = 0.153). Conclusion Distant metastasis was the major failure pattern for CASTLE after surgery and IMRT. For patients with no lateral neck node metastasis, the omission of irradiation for lateral neck nodal regions seems to be safe and feasible.

Kava (Piper methysticum Forst) is a popular and favorable edible medicinal herb which was traditionally used to prepare a nonfermented beverage with relaxant beneficial for both social and recreational purposes. Numerous studies conducted on kava have confirmed the presence of kavalactones and flavokawains, two major groups of bioactive ingredients, in this miraculous natural plant. Expectedly, both kavalactone and flavokawain components exhibited potent antianxiety and anticancer activities, and their structure-activity relationships were also revealed. However, dozens of clinical data revealed the hepatotoxicity effect which is indirectly or directly associated with kava consumption, and most of the evidence currently seems to point the compounds of flavokawains in kava were responsible. Therefore, our aim is to conduct a systematic review of kavalactones and flavokawains in kava including their biological activities, structure-activity relationships, and toxicities, and as a result of our systematic investigations, suggestions on kava and its compounds are supplied for future research.

Crack is the early form of most pavement defects and has a great negative effect on road service life. Timely detection and maintenance of cracks may minimize the loss caused by it. In this paper, we propose a lightweight crack segmentation model based on a bilateral segmentation network, which achieves a good balance between inference speed and segmentation performance. The model contains two parts: context path and spatial path. The network used in context path is inspired by Xception, which is used to rapidly down-sample the feature map. Spatial path employs three convolutional layers to encode sufficient spatial information. The F1_score and IoU achieved by our model on the Crack500 dataset are 0.8270 and 0.7379, respectively. The proposed model gains superior performance in FPS compared to other four models. In addition, the model is able to process images at 1,024 × 512 pixels in real-time (31.3 FPS). Through the comparison of training time, our model can save 54.04% of the time.

Oceanic islands are unique geographic systems that promote local adaptations and allopatric speciation in many of their highly endemic taxa. This is a common case in the Philippine Archipelago, where numerous unrelated taxa on islands have been inferred to have diversified in isolation. However, few cases have been reported in invertebrates especially among parasitic organisms. Here, we tested for biogeographical structure in novel populations of the “generalist" kleptoparasitic spider, Argyrodes lanyuensis Yoshida, Tso & Severinghaus, 1998 in the Philippines. Results showed that, in addition to Orchid/Lanyu Island, this species has a wide geographic distribution in the Philippine Archipelago. The estimated divergence time of this lineage using the mitochondrial cytochrome oxidase 1 (mt‐CO1) suggests that this species diverged ca 3.12 MYA, during the Pliocene. Two reciprocal monophyletic clades were elucidated in A. lanyuensis, but with limited differentiation across Pleistocene Aggregate Island Complex (PAIC) boundaries and modern‐day islands. However, in our analyses of morphological variation, we identified two phenotypically differentiated units in males (Orchid Island, Taiwan + Luzon, Philippine PAIC populations vs. Palawan + West Visayan + Mindanao PAIC populations). We infer that this species diverged in the southern portion of the Philippine Archipelago and only recently colonized Orchid Island. Our study provides new information on the extensive distribution of A. lanyuensis outside Orchid Island, Taiwan, but we documented a very limited geographically associated genetic variation. Our study points to behavioral phenomena such as foraging behavior as essential contributor to the evolutionary process of species diversification, in contrast to the traditionally invoked geographic drivers of divergence.

OBJECTIVE Chronic obstructive pulmonary disease (COPD) is a respiratory disease with high morbidity and mortality worldwide, so far there is no ideal treatment method. Previous studies have shown that hydrogen (H2) is involved in the treatment of COPD as an antioxidant. In this study, the effect of H2 on M1/M2 polarization of alveolar macrophages in COPD rats was observed, and its anti-inflammatory mechanism was further elucidated. Methods: Twenty-four Sprague-Dawley rats were randomly divided into three groups including the control, COPD and H2 group. A rat model of COPD was established by cigarette exposure combined with lipopolysaccharide (LPS) induction. H2 therapy was administered 2 hours per day for 14 days. Lung function and pathology were assessed. The levels of interleukin (IL)-6, tumor necrosis factor (TNF)-α, transforming growth factor (TGF)-β1 and IL-10 in bronchoalveolar lavage fluid (BALF) and lung tissue were measured by enzyme-linked immunosorbent assay. The mRNA, protein expression and immunoreactivity of inducible nitric oxide synthase (iNOS) and arginase (Arg)-1 in lung were observed by quantitative real-time PCR, western blot and immunohistochemistry. Results: Compared with the control rats, there were a significant decline in lung function, a marked inflammatory infiltration and pulmonary parenchymal remodeling and the increases of IL-6, TNF-α and TGF-β1 levels in BALF and lung tissue, but a lower expression of IL-10 in COPD rats. The iNOS mRNA and protein expression, as well as its optical density (OD), were increased significantly in lung tissue, while those of Arg-1 decreased significantly. H2 treatment improved the lung function and the parenchymal inflammation, reversed the increased levels of IL-6, TNF-α and TGF-β1, and the lower IL-10. Meanwhile, H2 also down-regulated the expression of iNOS, but up-regulated expression of Arg-1 in lung tissue. Conclusion: H2 reduces inflammation in the lung of COPD, which may be related to its inhibition of M1 type polarization and activation of M2 type polarization of alveolar macrophage.

The scholarship on media and communication studies focusing on Greater China has burgeoned in recent years. Yet, little is known about how such scholarship would tackle other sub-fields and the core debates and developments in communication studies beyond the scope of Greater China. In this introduction, we delineate six articles in the Special Issue ‘Comparative Communication Studies Within and Beyond China’ in terms of three layers of comparision consisting of the macro-level unit of analysis, the dimension of comparison, and the design and analysis strategy of comparison. Together, the articles deliver updated investigations about Greater China’s media and communicative environment, provide a comprehensive outlook on the insights to be gained from comparing the Greater Chinese media system with its counterparts across the world, and reflect on both differences and similarities between Greater China and other countries across a spectrum of social, political, and cultural factors.

Driven by globalization, modernity and the development of media technology, transnational media consumption is increasingly prevalent. Together with domestic media consumption, transnational media consumption constitutes the fragmentation and diversification of individuals’ media consumption behaviors. Yet research concerning the hybrid media effects generated by domestic and transnational media consumption is still underdeveloped. Using a sample of 556 Chinese Internet users, this study proposes a concept of transnational media consumption dissonance to compare the effects of hybrid media consumption on sexism and gender-role norms in marriage (GRIM). The findings suggest that individuals’ perceptions of gender-role norms are not only affected by domestic media usage but also altered through transnational media usage. We illustrate how transnational media consumption dissonance can affect Chinese audiences’ perception of GRIM through the mediating roles of perceived sexism in American and Korean dramas and their general sexism values.

Magnetorheological (MR) dampers, as an intelligent vibration damping device, can quickly change the damping size of the material in milliseconds. The traditional semiactive control strategy cannot give full play to the ability of the MR dampers to consume energy and reduce vibration under different currents, and it is difficult to control the MR dampers accurately. In this paper, a semiactive control strategy based on reinforcement learning (RL) is proposed, which is based on “exploring” to learn the optimal value of the MR dampers at each step of the operation, the applied current value. During damping control, the learned optimal action value for each step is input into the MR dampers so that they provide the optimal damping force to the structure. Applying this strategy to a two-layer frame structure was found to provide more accurate control of the MR dampers, significantly improving the damping effect of the MR dampers.

To observe the effect of electroacupuncture (EA) at "Zusanli"(ST36) pretreatment on lung functions, inflammatory response, and levels of angiotensin-converting enzyme 2 (ACE2) and angiotensin (1-7) ［Ang (1-7)］ in rats with sepsis-induced acute lung injury (ALI), so as to explore its mechanisms underlying improvement of ALI.Thirty male SD rats were randomly divided into normal, model and EA groups (Following modeling, the levels of FVC, FEV0.1, FEV0.3, ratio of FEV0.1/FVC and FEV0.3/FVC, content of Ang (1-7) in the BALF, and the expression levels of ACE2 and MasR mRNAs and proteins in the lung tissue were significantly decreased (EA preconditioning at ST36 can improve pulmonary function in sepsis-related ALI rats, which may be related to its effects in inhibiting inflammatory response and up-regulating ACE2 and MasR expression and Ang (1-7) content in the lung tissue.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is transmitted between humans and minks, and some mutations in the spike (S) protein, especially in the receptor-binding domain (RBD), have been identified in mink-derived viruses. Here, we examined binding of the mink angiotensin-converting enzyme 2 (ACE2) receptor to mink-derived and important human-originating variants, and we demonstrated that most of the RBD variants increased the binding affinities to mink ACE2 (mkACE2). Cryo-electron microscopy structures of the mkACE2-RBD Y453F (with a Y-to-F change at position 453) and mkACE2-RBD F486L complexes helped identify the key residues that facilitate changes in mkACE2 binding affinity. Additionally, the data indicated that the Y453F and F486L mutations reduced the binding affinities to some human monoclonal antibodies, and human vaccinated sera efficiently prevented infection of human cells by pseudoviruses expressing Y453F, F486L, or N501T RBD. Our findings provide an important molecular mechanism for the rapid adaptation of SARS-CoV-2 in minks and highlight the potential influence of the main mink-originating variants for humans.

PRDM5 is considered a tumor suppressor in several types of solid tumors and is involved in multiple cellular processes. However, target genes regulated by PRDM5 in lung cancer and its potential mechanism are poorly defined.Survival analysis was conducted using Kaplan-Meier estimates based on the online databases. RNA-sequencing and bioinformatics analysis were performed to identify the differentially expressed genes in PRDM5-overexpressed A549 cells.We observed deregulated PRDM5 in several lung adenocarcinoma cell lines and its association with a poor prognosis. PRDM5 overexpression inhibited the proliferation of lung adenocarcinoma cells in vitro and suppressed tumor growth in a xenograft model. PRDM5 upregulated the promoter activity of SOCS1, which then inhibited the phosphorylation of JAK2 and STAT3.Our study suggests that the low expression of PRDM5 promotes the proliferation of lung adenocarcinoma cells by downregulating SOCS1 and then upregulating the JAK2/STAT3 signaling pathway.

The root nodule symbiosis with its global impact on nitrogen fertilization of soils is characterized by an intracellular colonization of legume roots by rhizo-bacteria. While the symbionts are initially taken up by morphologically adapted root hairs, rhizobia persistently progress within a membrane-confined infection thread through several root cortical and later nodular cell layers. Throughout this transcellular passaging, rhizobia have to repeatedly pass host plasma membranes and cell walls. Here, we genetically dissected this essential process and describe the concerted action of the symbiosis-specific pectin methyl esterase SyPME and the pectate lyase NPL at the infection thread and transcellular passage sites. Their coordinated function mediates spatially confined pectin alterations in the cell-cell interface that result in the establishment of an apoplastic compartment where bacteria are temporarily released into and taken up from the subjacent cell. This process allows successful intracellular progression of infection threads through the entire root cortical tissue.

Water leakage is a critical factor reflecting the structural safety of shield tunnels. Computer vision provides new opportunities to overcome the shortcomings of manual visual inspection and realize automatic detection of water leakage regions. In this study, we propose a leakage segmentation model with an encoder–decoder structure. The encoder adopts multi-branch convolutional attention for feature fusion, and the decoder adopts a lightweight design that only contains multi-layer perceptron. Standard convolution in multi-branch is decomposed to two depth-wise strip convolutions to realize lightweight design and extract strip-like features. Extensive ablation and comparative studies were conducted to test model performance. Test results show that our model achieves robust detection of water leakage under strong noise background, reaching an intersection over union of 90.75% with performance-computation trade-off. Consequently, the proposed method can be an effective alternative to the current visual inspection technologies, and provide a nearly automated inspection platform for shield tunnels.

High-temperature solid-state electrolyte is a key component of several important electrochemical devices, such as oxygen sensors for automobile exhaust control, solid oxide fuel cells (SOFCs) for power generation, and solid oxide electrolysis cells for H2 production from water electrolysis or CO2 electrochemical reduction to value-added chemicals. In particular, internal diffusion of protons or oxygen ions is a fundamental and crucial issue in the research of SOFCs, hypothetically based on either oxygen-ion-conducting electrolytes or proton-conducting electrolytes. Up to now, some electrolyte materials based on fluorite or perovskite structure were found to show certain degree of dual-ion transportation capability, while in available electrolyte database, particularly in the field of SOFCs, such dual-ion conductivity was seriously overlooked. Actually, few concerns arising to the simultaneous proton and oxygen-ion conductivities in electrolyte of SOFCs inevitably induce various inadequate and confusing results in literature. Understanding dual-ion transportation behavior in electrolyte is indisputably of great importance to explain some unusual fuel cell performance as reported in literature and enrich the knowledge of solid state ionics. On the other hand, exploration of novel dual-ion conducting electrolytes will benefit the development of SOFCs. In this review, we provide a comprehensive summary of the understanding of dual-ion transportation in solid electrolyte and recent advances of dual-ion conducting SOFCs. The oxygen ion and proton conduction mechanisms at elevated temperature inside oxide-based electrolyte materials are first introduced, and then (mixed) oxygen ion and proton conduction behaviors of fluorite and perovskite-type oxides are discussed. Following on, recent advances in the development of dual-ion conducting SOFCs based on fluorite and perovskite-type single-phase or composite electrolytes, are reviewed. Finally, the challenges in the development of dual-ion conducting SOFCs are discussed and future prospects are proposed.

Skin pigmentation depends not only on melanosomes produced by melanocytes but also on the migration of melanosomes to adjacent keratinocytes and their distribution on the skin surface. The inhibitory effects of cardanol diene (CADI), a major phenolic compound extracted from cashew nut shell liquid (CNSL), on melanin transfer in B16F10-HaCAT co-culture cells and a crude extracted compound of cashew nut shell oil (CNCE) on melanin production in zebrafish were investigated. β-arbutin was used as a positive control. CADI inhibited the expression levels of the melanin phagocytosis-associated protein PAR-2 and filopodia-associated protein NMDAR1, and the effect was better than that of β-arbutin at the same concentration. To further study the inhibitory mechanism of CADI in melanin transfer, fluorescence microspheres were used to simulate melanin and co-culture with keratinocytes. The results indicated that CADI inhibited melanin transfer through suppressing keratinocyte phagocytosis, dendrite formation and filopodia three channels. We also found that CNCE inhibited melanin production in zebrafish and showed significant inhibitory effects on TYR, DCT and α-MSH. Thus, the natural components extracted from CNSL effectively inhibited skin pigmentation, providing insight into the application of new anti-melanin drugs in cosmetics and medicine.

Kava, the rhizomes and roots of Piper methysticum Forst, is a popular edible medicinal herb traditionally used to prepare beverages for anxiety reduction. Since the German kava ban has been lifted by the court, the quality evaluation is particularly important for its application, especially the flavokawains which were believed to be responsible for hepatotoxicity. Now, by employing two different standard references and four different methods to calculate the relative correction factors, eight different quantitative analyses of multicomponents by single-marker methods have been developed for the simultaneous determination of eight major kavalactones and flavokawains in kava. The low standard method difference on quantitative measurement of the compounds among the external standard method and ours confirmed the reliability of the mentioned methods. A radar plot clearly illustrated that the contents of dihydrokavain and kavain were higher, whereas flavokawains A and B were lower in different kava samples. Only one of eight samples did not detect flavokawains that may be related to hepatotoxicity. In summary, by using different agents as an internal standard reference, the developed methods were believed as a powerful analytical tool not only for the qualitative and quantitative of kava constituents but also for the other multicomponents when authentic standard substances were unavailable.

This study investigates the relationships between social connectedness and communication patterns from seven countries across the globe. In contrast to most existing studies, which focus on either single medium use or ICT-mediated multimodal connectedness, the study considers how people select and combine a set of communication modes for social connectedness. With survey data from the United States, the United Kingdom, Denmark, Germany, Italy, Hungary, and the Chinese mainland, the study examines the complexity of multimodal connectedness, that is, the diversity and the frequency of multiple communication modes and media through which people maintain their connections with different social relations. A latent class analysis identifies six clusters in the diversity and the frequency to illustrate the similarities and differences of communication patterns. Sociodemographic and country variables play distinct roles in predicting the clusters in the diversity and frequency dimensions, respectively. The theoretical and practical implications of this comparative study are discussed.

Over time, the uneven settlements of the structure and foundation are prominent in constructing ship lock heads on soft soil. These deformations endanger the safety of ship lock heads during construction. This research aimed to establish the ship lock head’s structural optimization procedure on soft soil, considering the time-varying effects of the structure and foundation. By comprehensively considering the linear viscoelastic creep of concrete and the elastoplastic consolidation characteristic of soft soil, a perfect time-dependent analysis method for the lock head on soft soil was proposed. Furthermore, a hybrid particle swarm optimization, enhanced whale optimization, and differential evolution (PSO-EWOA-DE) algorithm was proposed to optimize thirty-four design variables of a lock head. With the minimal volume of the lock head as the optimization objective, the finite element model was established. In the optimization process, three types of constraints were evaluated. The result showed that the optimized design could reduce 10.45% of structure volume. Through comparing and analysing the maximum principle stresses and vertical displacements of the lock head before and after optimization, some conclusions were drawn. The optimization procedure proposed in this paper provides a new perspective for the structural optimization of hydraulic structures on soft soil.

Doxorubicin (DOX) is an anthraquinone drug used for the efficient treatment of a variety of tumors in human beings. Unfortunately, its poor biodegradability causes incomplete metabolism in the body. Therefore, it is of great significance to synthesize a sensitive and selective material for DOX detection. In this paper, we report a water-soluble Tb

In this study, taking the Beijing-Tianjin-Hebei region as an example, CMAQ and BETR models were constructed to carry out numerical simulation for the pyrene (Pyr) and benzo[a] pyrene (BaP) in 2014. The model results were compared and evaluated for the atmospheric transportation and transformation of PAHs. Additionally, the XGBoost model was used to identify the key atmospheric physicochemical processes and parameters that affect the environmental behavior of PAHs in the CMAQ. The results showed that the ratio of the simulated value of BETR and annual average value of CMAQ to the measured annual average value was between 1/2 and 2, and the seasonal trend of the simulated concentrations of Pyr and BaP from the CMAQ model were basically consistent with the measured values, which verified the reliability of the two types of models. At the same time, the simulated concentration of the CMAQ model averaged from 9 km grid to 27 km grid and was comparable to the BETR concentration. The results showed that the average concentrations of Pyr and BaP in the BETR model were approximately 1.59 and 1.38 times those of the CMAQ simulation concentrations, respectively, indicating that the two models had good comparability in terms of average annual concentration level and spatial distribution. The SHAP-based variable importance on the XGBoost model showed that boundary layer height was the most significant meteorological factor affecting the transportation and transformation of Pyr and BaP, accounting for 22%-35% of all factors, and sometimes even exceeded the emissions for certain cities and pollutants. The boundary layer height was significantly negatively correlated with the concentration of PAHs. Wind speed was a secondary factor affecting the concentration of PAHs and was negatively correlated with the PAHs, whereas the influence of wind direction on the concentration of PAHs varied.

Host-controlled intracellular accommodation of nitrogen-fixing bacteria is essential for the establishment of a functional Root Nodule Symbiosis (RNS). In many host plants, this occurs via transcellular tubular structures (infection threads - ITs) that extend across cell layers via polar tip-growth. Comparative phylogenomic studies have identified RPG (RHIZOBIUM-DIRECTED POLAR GROWTH) among the critical genetic determinants for bacterial infection. In Medicago truncatula, RPG is required for effective IT progression within root hairs but the cellular and molecular function of the encoded protein remains elusive. Here, we show that RPG resides in the protein complex formed by the core endosymbiotic components VAPYRIN (VPY) and LUMPY INFECTION (LIN) required for IT polar growth, co-localizes with both VPY and LIN in IT tip- and perinuclear-associated puncta of M. truncatula root hairs undergoing infection and is necessary for VPY recruitment into these structures. Fluorescence Lifetime Imaging Microscopy (FLIM) of phosphoinositide species during bacterial infection revealed that functional RPG is required to sustain strong membrane polarization at the advancing tip of the IT. In addition, loss of RPG functionality alters the cytoskeleton-mediated connectivity between the IT tip and the nucleus and affects the polar secretion of the cell wall modifying enzyme NODULE PECTATE LYASE (NPL). Our results integrate RPG into a core host machinery required to support symbiont accommodation, suggesting that its occurrence in plant host genomes is essential to co-opt a multimeric protein module committed to endosymbiosis to sustain IT-mediated bacterial infection.

Evolutionary transitions from solitary to group-living are ubiquitous in animal systems. While the fitness consequences of group size changes are often investigated, the long-standing debate on whether kinship is a prerequisite of sociality is still ongoing. In the current study, we used kleptoparasitic spiders Argyrodes miniaceus (subfamily Argyrodinae, Theridiidae) as a model system to assess the role of group size on the foraging payoffs of kin and non-kin groups. We set up laboratory-manipulated kin and non-kin foraging groups and used feeding occurrence and duration as proxies for foraging benefits and feeding latency and the number of host attacks as estimates of foraging costs. Compared to solitary individuals, feeding durations of successfully fed individuals in groups was not significantly different from that of solitary foragers in both kin and non-kin groups. The occurrences of feeding decreased significantly in group sizes two and above, in non-kin groups, and in group sizes three and above, in kin groups. In kin groups, groups size two had significantly shorter feeding latencies compared to other group sizes, even though feeding duration did not change systematically with group size. Similarly, the number of attacks from the hosts were highest in non-kin groups with more than two individuals and in kin groups with more than three individuals. The juxtaposition of kin and non-kin group showed that A. miniaceus enjoyed the highest foraging payoffs when being solitary or in small groups (group size two). However, host attacks appeared to hamper feeding occurrences in kin groups, which was not observed in non-kin groups. Our results contrast sharply with the feeding benefits of kinship recorded in kin-based groups of sub-social species present in related subfamilies in the Theridiidae.

El Niño Southern Oscillation (ENSO)-linked climate patterns have been known to be associated with several rodent species, but the effects of ENSO on rodent populations at both the spatial and temporal scales in wild natural plague foci of southern China, have not been thoroughly studied. In this study, we investigated the possible natural environmental factors relating ENSO, precipitation, relative humidity and surface temperatures to the populations of 2 allopatric rodent species (Apodemus chevrieri and Rattus tanezumi) in Jianchuan county the most important core area of the natural foci of wild plague in southern China from 1978 to 2019. Our results indicated that ENSO-driven climate factors, such as the Southern Oscillation Index (SOI), rainfall, surface temperature, and other biological factors, all affected the rodent population densities. We found that sympatric rodent species with different life histories respond differently to precipitation and surface temperature, while SOI had a similar effect on the population densities of these two species, and the effect of SOI on rodent population densities was time-dependent. Additionally, nonlinear negative relationships were established between the population density of rodents and SOI, and El Niño events were found to be beneficial for increasing the rodent density, whereas La Niña events were favorable for decreasing the rodent density. The cross-wavelet analysis results revealed that the rodent population density oscillated in an anti-phase pattern with SOI over a period of approximately 2-3 years before 1995 but has oscillated in-phase with SOI over the same periods since 1995. These results indicate that ENSO-driven climate variations may significantly impact rodent population dynamics in Jianchuan county, and SOI, a large-scale climate factor, has the same effect on sympatric rodent species with different life histories.

To observe the effect of electroacupuncture (EA) at "Zusanli" (ST36) and "Feishu" (BL13) on the activation and secretion of calcitonin gene-related peptide (CGRP) and 5-hydroxytryptamine (5-HT) of pulmonary neuroendocrine cells (PNECs) and inflammatory response in rats with chronic obstructive pulmonary disease (COPD), so as to explore its underlying mechanisms in treating COPD.Male SD rats were randomly divided into normal control, COPD model and EA groups, with 7 rats in each group. The COPD model was established by forced inhale of cigarette smoke for 1 h in a self-made box (1 m×1 m×1 m in volume), twice daily for 12 weeks. EA (4 Hz/20 Hz, 1-3 mA) was applied at bilateral ST36 and BL13 acupoints for 30 min, once a day for 14 consecutive days. The pulmonary function including the forced vital capacity (FVC), forced expiratory volume at 0.1 second (FEV0.1), FEV0.3, FEV0.1/FVC and FEV0.3/FVC was detected using a lung function analyzer for small animals. The lung tissue was sampled for observing histopathological changes by using H.E. staining, for observing expression and distribution of PNECs by Grimelius silver staining, and for detecting the immunoactivity (integrated optical density) of CGRP and 5-HT by using immunohistochemistry. The contents of CGRP, 5-HT, tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and transforming growth factor-β1 (TGF-β1) in the bronchoalveolar lavage fluid (BALF) and lung tissue were detected by ELISA, and the correlations between TNF-α and CGRP, IL-1β and CGRP, TNF-α and 5-HT, and IL-1β and 5-HT levels were analyzed. The mRNA and protein expression levels of nerve fiber markers of CGRP and purinergic receptor P2X ligand gated ion channel 3 (P2X3) which dominate PNECs in the lung tissue were detected by real-time fluorescence quantitative PCR and Western blot, respectively.Compared with the normal control group, the levels of FVC, FEV0.1, FEV0.3, and the ratios of FEV0.1/FVC and FEV0.3/FVC were significantly decreased (EA at ST36 and BL13 can improve lung function and reduce inflammatory response in COPD rats, which may be related to its function in inhibiting the activation of PNECs and release of neuroactive substances.

The role of surgery in nasopharyngeal carcinoma liver metastases (NCLM) remains elusive, and the current application is limited. We aim to investigate whether hepatic resection (HR) of NCLM improves survival compared with non-hepatic resection (NHR) treatment.One hundred and thirty-three patients with NCLM from 2007 to 2017 were divided into two groups. Propensity score matching (PSM) analysis was used to compare the clinical outcomes.After PSM the median overall survival (OS) and the 1, 3 and 5-year OS rates in HR group were 32.60 months, 86.2%, 37.3% and 37.3%, respectively; while for NHR group these values were 19.57 months, 61.5%, 12.9% and 2.9%, respectively (P = 0.008). Multivariate analysis indicated hepatitis B virus infection (P = 0.029) and hepatic resection (P = 0.018) were independent prognostic factors.Our study revealed that hepatectomy yields a survival benefit safely compared with systemic treatments, especially for patients with the size of largest metastasis5 cm, unilobar distribution of liver tumor and received unanatomical hepatectomy.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has an extremely broad host range that includes hippopotami, which are phylogenetically closely related to whales. The cellular ACE2 receptor is one of the key determinants of the host range. Here, we found that ACE2s from several marine mammals and hippopotami could efficiently bind to the receptor-binding domain (RBD) of both SARS-CoV and SARS-CoV-2 and facilitate the transduction of SARS-CoV and SARS-CoV-2 pseudoviruses into ACE2-expressing cells. We further resolved the cryo-electron microscopy complex structures of the minke whale ACE2 and sea lion ACE2, respectively, bound to the RBDs, revealing that they have similar binding modes to human ACE2 when it comes to the SARS-CoV-2 RBD and SARS-CoV RBD. Our results indicate that marine mammals could potentially be new victims or virus carriers of SARS-CoV-2, which deserves further careful investigation and study. It will provide an early warning for the prospective monitoring of marine mammals.