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Abstract Immediate oral implant placement is a widely accepted technique, known for its efficacy in reducing treatment duration, surgical visits, and overall healing time. One of the primary challenges associated with immediate implant placement is the attainment of initial stability. The inevitable loss of bone and soft tissue after extraction poses a risk to implant osseointegration in both vertical and horizontal dimensions. Guided tissue regeneration/guided bone regeneration (GTR/GBR) is a well‐established method for periodontal regeneration. However, current GTR/GBR membranes lack tissue inherent regeneration properties and necessitate combination with grafts to enhance tissue recovery. In this context, biomaterials have emerged as a promising option due to their good biocompatibility, biodegradability, and bioactive properties. They present a potential alternative to standard autologous/allograft procedures. The field of biomaterials for bone regeneration has rapidly evolved, developing new guiding materials and engineering techniques. These advances have become integral in addressing tissue defects at the immediate implant site. Various materials such as bioceramics, natural polymers, and synthetic polymers have been used for tissue repair. This article undertakes an etiological examination of tissue deficiency associated with immediate implant placement. Additionally, it reviews the advantages and disadvantages of a variety of biomaterials, aiming to provide references for clinical treatment and areas for further investigation.

Objective To investigate the situation of hepatitis E virus(HEV) infection among voluntary blood donors in Wuhan area and provide evidences for enhancing blood screening strategies. Methods HEV nucleic acid detection(NAT) was performed on blood samples from eligible blood donors in Wuhan from November to December 2020. The testing results were analyzed, and the blood donors with repeated reactive results were followed up to clarify the status of infection. Results Routine screening was performed on 17 409 blood samples from November to December 2020. A total of 17 322 blood samples of eligible blood donors were tested for HEV NAT, and one case of HEV RNA reactivity was detected. The results from the follow-ups showed that the blood donor should be in the window period of HEV seroconversion. The current HEV infection rate of voluntary blood donors in Wuhan arewas 0.058‰(1/17 322), which was lower than other domestic areas. Conclusion The current HEV infection rate of voluntary blood donors was at a relatively low prevalence level in Wuhan area. Selective blood screening strategies can be taken to further reduce potential risk of blood transfusion infection with hepatitis E virus.

Although tumor necrosis factor receptor 2 (TNFR2) may serve a protumor role in several types of tumors, the clinical significance of TNFR2, including the diagnostic and prognostic value in tumor (T) stage 2-3 esophageal squamous cell carcinoma (ESCC), remains unclear. Therefore, the present study aimed to explore the clinical significance of TNFR2 in stage T2-3 ESCC. The present study collected the mRNA expression data of TNFR2 from two databases and confirmed the high expression of TNFR2 in ESCC tissue. TNFR2 expression in stage T2-3 ESCC tissue (n=404) was detected using immunohistochemistry and a stratified analysis was performed. For all patients with stage T2-3 ESCC, TNFR2 expression was associated with clinical stage, invasion depth and metastatic lymph nodes. Stage T3 and low differentiation was associated with an increase in the risk of lymph node metastasis, but older age was associated with a decrease. TNFR2 expression was associated with poor overall survival (OS) of all patients with stage T2-3 ESCC and stratified patients with stage T3 ESCC. Moreover, TNFR2 expression and metastatic lymph nodes were independent prognostic factors for these patients. For stratified patients aged ≤60 years, TNFR2 expression was associated with clinical stage and metastatic lymph nodes. In addition, TNFR2 expression was associated with poor OS in stratified patients with stage T2 ESCC. The presence of metastatic lymph nodes was also an independent prognostic factor for these patients. For stratified patients aged >60 years, TNFR2 expression was associated with invasion depth. TNFR2 expression was also associated with poor OS in all patients with stage T2-3 ESCC and stratified patients with stage T3 ESCC. TNFR2 expression and meta-static lymph nodes were identified as independent prognostic factors for these patients. In conclusion, TNFR2 expression is associated with progression and poor prognosis in patients with stage T2-3 ESCC as an independent prognostic factor, except in the subgroup of patients with stage T2-3 ESCC aged ≤60 years. [ABSTRACT FROM AUTHOR]

The massive CO2 emission has caused frequent occurrence of climate problems, and a typical response to climate change has reached international consensus. Digital finance and green finance, as a subversion of the traditional financial model, have become significant drivers of global carbon emissions reduction efforts. Based on the panel data, this paper profoundly compares the effects of carbon emissions reduction, mechanisms, and heterogeneous results of two forms of finance. Research finds that technology-centered digital finance focuses on suppressing carbon emissions through technological innovation, and the higher the level of regional economic is, the stronger the role of digital finance in suppressing carbon emissions through technological innovation. The concept-centered green finance focuses on carbon emissions reduction through industrial ecologization, and government-led environmental regulation plays a positive regulatory role. Although the paths of affecting carbon emissions are different, there is a natural fit between the two in terms of the essential goal of carbon emissions reduction. Based on the consideration of the differences in geographic location and financial development level, the carbon emission reduction effects of two forms of finance show apparent heterogeneity. Based on the spatial characteristics of digital finance and carbon emissions, this paper further finds that the digital finance’s carbon emission reduction effects have apparent spatial spillovers. These findings provide an essential direction to formulate a reasonable carbon emissions reduction plan and accelerate realizing the “double carbon” goal.

ABSTRACT Hyperuricemia has become the second most prevalent metabolic disease after diabetes, but the limitations of urate-lowering treatment (ULT) drugs and patient nonadherence make ULT far less successful. Thus, more ULT approaches urgently need to be explored. Uric acid-degrading bacteria have potential application value in ULT. In this study, we isolated 44XBT, a uric acid-degrading bacterium, from black-headed gull (Chroicocephalus ridibundus) feces. Using a polyphasic taxonomic approach, strain 44XBT was identified as a novel genus within the family Bacillaceae; subsequently, the name Aciduricibacillus chroicocephali was proposed. Strain 44XBT had a unique uric acid-dependent phenotype and utilized uric acid and allantoin as the sole carbon and nitrogen sources, but not common carbon sources or complex media. In the genome, multiple copies of genes involved in uric acid metabolic pathway (pucL, pucM, uraD, and allB) were found. Six copies of pucL (encoding urate oxidase) were detected. Of these, five pucL copies were in a tandem arrangement and shared 70.42%–99.70% amino acid identity. In vivo experiments revealed that 44XBT reduced serum uric acid levels and attenuated kidney damage in hyperuricemic mice through uric acid catalysis in the gut and gut microbiota remodeling. In conclusion, our findings discover a strain for studying bacterial uric acid metabolism and may provide valuable insights into ULT.IMPORTANCEThe increasing disease burden of hyperuricemia highlights the need for new therapeutic drugs and treatment strategies. Our study describes the developmental and application values of natural uric acid-degrading bacteria found in the gut of birds and broadened the source of bacteria with potential therapeutic value. Furthermore, the special physiology characteristics and genomic features of strain 44XBT are valuable for further study.

Background: Kidney renal clear cell carcinoma (KIRC) is a common and clinically significant subtype of kidney cancer. A potential therapeutic target in KIRC is disulfidptosis, a novel mode of cell death induced by disulfide stress. The aim of this study was to develop a prognostic model to explore the clinical significance of different disulfidptosis gene typings from KIRC.Methods: A comprehensive analysis of the chromosomal localization, expression patterns, mutational landscape, copy number variations, and prognostic significance of 10 disulfide death genes was conducted. Patients were categorized into distinct subtypes using the Non-negative Matrix Factorization (NMF) typing method based on disulfidptosis gene expression patterns. Weighted Gene Co-expression Network Analysis (WGCNA) was used on the KIRC dataset to identify differentially expressed genes between subtype clusters. A risk signature was created using LASSO-Cox regression and validated by survival analysis. An interaction between risk score and immune cell infiltration, tumor microenvironment characteristics and pathway enrichment analysis were investigated.Results: Initial findings highlight the differential expression of specific DRGs in KIRC, with genomic instability and somatic mutation analysis revealing key insights into their role in cancer progression. NMF clustering differentiates KIRC patients into subgroups with distinct survival outcomes and immune profiles, and hierarchical clustering identifies gene modules associated with key biological and clinical parameters, leading to the development of a risk stratification model (LRP8, RNASE2, CLIP4, HAS2, SLC22A11, and KCTD12) validated by survival analysis and predictive of immune infiltration and drug sensitivity. Pathway enrichment analysis further delineates the differential molecular pathways between high-risk and low-risk patients, offering potential targets for personalized treatment. Lastly, differential expression analysis of model genes between normal and KIRC cells provides insights into the molecular mechanisms underlying KIRC, highlighting potential biomarkers and therapeutic targets.Conclusion: This study contributes to the understanding of KIRC and provides a potential prognostic model using disulfidptosis gene for personalized management in KIRC patients. The risk signature shows clinical applicability and sheds light on the biological mechanisms associated with disulfide-induced cell death.

Primary and metastatic lung cancers are malignant lung tumors each with of which has a different pathogenesis, although both threaten patient lives. Tumor development and progression involve communication between tumor cells and the host microenvironment. Neutrophils are the most abundant immune cells in the tumor microenvironment (TME); they participate in the generation of an inflammatory milieu and influence patient survival through their anti- and pro-tumor abilities. Neutrophils can be classified into various categories according to different criteria; frequent categories include N1 antitumor neutrophils and N2 immunosuppressive neutrophils. The antitumor effects of neutrophils are reported to be mediated through a combination of reactive oxygen species, tumor necrosis factor-related apoptosis-inducing ligand, and receptor for advanced glycation end-products–cathepsin G association, as well as the regulation of the activities of other immune cells. There have also been reports that neutrophils can function as tumor promoters that contribute to lung cancer progression and metastasis by influencing processes including carcinogenesis, angiogenesis, cancer cell proliferation, and invasion ability, as well as having similar roles in the lung metastasis of other cancers. The rapid development of nanotechnology has provided new strategies for cancer treatment targeting neutrophils.

BackgroundHealthcare professionals have shown more psychological disorders such as anxiety and depression due to the nature of work, which can cause job burnout, decrease the quality of medical services, and even endanger medical safety. The aim of the study is to explore the serial multiple mediating role of effort- reward imbalance and resilience between perceived stress and psychological disorders among healthcare professionals.MethodsA cross-sectional study was conducted in China from February to April 2023. A total of 2098 healthcare professionals at a tertiary general hospital was investigated by the following self-reported questionnaires: Hospital Anxiety and Depression Scale (HADS), Perceived Stress Scale (PSS), The Effort-Reward Imbalance (ERI), Healthcare professionals Resilience Scale (MSRS).ResultsAnxiety and depression are interrelated (r = 0.362, p

ABSTRACTHuman cytomegalovirus (HCMV) infection is prevalent worldwide, and there is currently no licenced HCMV vaccine to control it. Therefore, developing an effective HCMV vaccine is a significant priority. Because of their excellent immunogenicity, the crucial components of HCMV, phosphoprotein 65 (pp65) and glycoproteins H (gH) are potential target proteins for HCMV vaccine design. In this study, we predicted and screened the dominant antigenic epitopes of B and T cells from pp65 and gH conjugated with the carrier protein cross-reacting material 197 (CRM197) to form three peptide-CRM197 vaccines (pp65-CRM197, gH-CRM197, and pp65-CRM197+gH-CRM197). Furthermore, the immunogenicity of the peptide-CRM197 vaccines and their effects on dendritic cells (DCs) were explored. The results showed that three peptide-CRM197 vaccines could induce maturation of DCs through the p38 MAPK signalling pathway and promote the release of proinflammatory factors, such as TNF-α and interleukin (IL) −6. Meanwhile, the peptide-CRM197 vaccines could effectively activate T cell and humoral immunity, which were far better than the inactivated HCMV vaccine. In conclusion, we constructed three peptide-CRM197 vaccines, which could induce multiple immune effects, providing a novel approach for HCMV vaccine design.

Abstract Metabolic diseases are often associated with high fructose (HF) consumption. HF has also been found to alter the gut microbiota, which then favors the development of nonalcoholic fatty liver disease. However, the mechanisms underlying of the gut microbiota on this metabolic disturbance are yet to be determined. Thus, in this study, we further explored the effect the gut microbiota concerning the T cells balance in an HF diet mouse model. We fed mice 60% fructose-enriched diet for 12 weeks. At 4 weeks, HF diet did not affect the liver, but it caused injury to the intestine and adipose tissues. After 12 weeks, the lipid droplet aggregation was markedly increased in the liver of HF-fed mice. Further analysis of the gut microbial composition showed that HF decreased the Bacteroidetes/Firmicutes ratio and increased the levels of Blautia, Lachnoclostridium, and Oscillibacter. In addition, HF can increase the expression of pro-inflammatory cytokines (TNF-α, IL-6, and IL-1β) in the serum. T helper type 1 cells were significantly increased, and regulatory T(Treg) cells were markedly decreased in the mesenteric lymph nodes of the HF-fed mice. Furthermore, fecal microbiota transplantation alleviates systemic metabolic disorder by maintaining liver and intestinal immune homeostasis. Overall, our data indicated that intestinal structure injury and intestinal inflammation might be early, and liver inflammation and hepatic steatosis may be a subsequent effect following HF diets. Gut microbiota disorders impairing the intestinal barrier function and triggering immune homeostasis imbalance may be an importantly responsible for long-term HF diets induced hepatic steatosis.

Rice not only plays an important role in people's daily diet, but also makes a huge contribution to China's agricultural products trade. However, heavy metal contamination in rice has become one of the main hazards about rice production and human health in China. In this paper, the main sources, existing forms, detection and analysis methods of heavy metal contamination in rice are reviewed, furthermore, the current situation, prevention and control measures, risk assessment of heavy metal contamination in rice are summarized. This review would provide a theoretical reference for the effective prevention and control, and the accurate risk assessment of heavy metal contamination in rice.

Atherosclerosis is still the main cause of death in developed and developing countries. Vascular smooth muscle cells (VSMCs) death disorder is a key pathogens of atherosclerosis. During the early stage of human cytomegalovirus (HCMV) infection, immediate early protein 2 (IE2) is critical in regulating its host cell death to ensure HCMV replication. Abnormal cell death induced by HCMV infection contributes to the development of numerous diseases, including atherosclerosis. Hitherto, the underlying mechanism of HCMV involved in the progression of atherosclerosis is still unclear. In this study, the infection models in vitro and in vivo were constructed to explore the pathogenesis of HCMV-related atherosclerosis. Our results indicated that HCMV could contribute to the progression of atherosclerosis by enhancing the proliferation, invasion, and inhibiting the pyroptosis of VSMCs under inflammatory conditions. Meanwhile, IE2 played a key role in these events. Our present research revealed a novel pathogenesis of HCMV-related atherosclerosis, which might help develop new therapeutic strategies.

By distinguishing between two types of neutralizing antibodies that either exhibit or lack antibody-dependent enhancement (ADE) activity, FcγRIIB and bivalent binding are shown to be required for ADE in SARS-CoV-2 infection.

Summary: Larger vehicles, such as sports utility vehicles, consume more energy than cars. Their increasing popularity runs contrary to the goal of fuel economy regulations to reduce fossil fuel consumption and greenhouse gas emissions and can be explained by consumer preference and lower regulation stringency, which is due to footprint, truck classification, and the omission of heterogenous lifetime vehicle distance traveled among vehicle classes. This study shows that, for both the US and China, large vehicles travel more, last longer, and are owned by higher income consumers. This means large vehicles and their high-income owners use more fuel and emit more pollutants than represented by current policy and thus raises both policy effectiveness and energy equity concerns. We propose and estimate Sales Adjustment Factors that weigh fuel economy standards based on vehicle lifetime usage and demonstrate the resultant significant improvements in the effectiveness and equity of fuel economy regulations.

N6-methyldeoxyadenosine (6mA) is a recently discovered DNA modification involved in regulating plant adaptation to abiotic stresses. However, the mechanisms and changes of 6mA under cold stress in plants are not yet fully understood. Here, we conducted a genome-wide analysis of 6mA and observed that 6mA peaks were predominantly present within the gene body regions under both normal and cold conditions. In addition, the global level of 6mA increased both in Arabidopsis and rice after the cold treatment. The genes that exhibited an up-methylation showed enrichment in various biological processes, whereas there was no significant enrichment observed among the down-methylated genes. The association analysis revealed a positive correlation between the 6mA level and the gene expression level. Joint analysis of the 6mA methylome and transcriptome of Arabidopsis and rice unraveled that fluctuations in 6mA levels caused by cold exposure were not correlated to changes in transcript levels. Furthermore, we discovered that orthologous genes modified by 6mA showed high expression levels; however, only a minor amount of differentially 6mA-methylated orthologous genes were shared between Arabidopsis and rice under low-temperature conditions. In conclusion, our study provides information on the role of 6mA in response to cold stress and reveals its potential for regulating the expression of stress-related genes.

Since the outbreak of the coronavirus disease 2019 (COVID-19) pandemic, several variants of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have emerged and have consistently replaced the previous dominant variant. Therapeutics against variants of SARS-CoV-2 are urgently needed. Ideal SARS-CoV-2 therapeutic antibodies would have high potency in viral neutralization against several emerging variants. Neutralization antibodies targeting SARS-CoV-2 could provide immediate protection after SARS-CoV-2 infection, especially for the most vulnerable populations. In this work, we comprehensively characterize the breadth and efficacy of SARS-CoV-2 RBD-targeting fully human monoclonal antibody (mAb) MW3321. MW3321 retains full neutralization activity to all tested 12 variants that have arisen in the human population, which are assigned as VOC (Variants of Concern) and VOI (Variants of Interest) due to their impacts on public health. Escape mutation experiments using replicating SARS-CoV-2 pseudovirus show that escape mutants were not generated until passage 6 for MW3321, which is much more resistant to escape mutation compared with another clinical staged SARS-CoV-2 neutralizing mAb MW3311. MW3321 could effectively reduce viral burden in hACE2-transgenic mice challenged with either wild-type or Delta SARS-CoV-2 strains through viral neutralization and Fc-mediated effector functions. Moreover, MW3321 exhibits a typical hIgG1 pharmacokinetic and safety profile in cynomolgus monkeys. These data support the development of MW3321 as a monotherapy or cocktail against SARS-CoV-2-related diseases.

Human cytomegalovirus (HCMV) is a β-herpesvirus whose genome consists of double stranded linear DNA. HCMV genome can generate non-coding RNAs (ncRNAs) through transcription in its host cells. Besides that, HCMV infection also changes the ncRNAs expression profile of the host cells. ncRNAs play a key role in maintaining the normal physiological activity of cells, and the disorder of ncRNAs expression has numerous adverse effects on cells. However, until now, the relationship between ncRNAs and HCMV-induced adverse effects are not summarized in detail. This review aims to give a systematic summary of the role of HCMV infection in ncRNAs expression while providing insights into the molecular mechanism of unnormal cellular events caused by ncRNAs disorder. ncRNAs disorder induced by HCMV infection is highly associated with cell proliferation, apoptosis, tumorigenesis, and immune regulation, as well as the development of cardiovascular diseases, and the potential role of biomarker. We summarize the studies on HCMV associated ncRNAs disorder and suggest innovative strategies for eliminating the adverse effects caused by HCMV infection.

Abstract Human skin moisture is closely related to health and personal care issues. Many creams were developed to claim capable of skin moisturizing. However, people can hardly check their skin moisture status and the moisturizing effect of various creams conveniently, since currently all the skin moisturizing detection rely on large equipment requiring power supply. Herein, we report a power‐supply independent supramolecular film that is able to directly report the moisturizing status of the skin. With the strategy of solid‐phase molecular self‐assembly (SPMSA), the aqueous precipitates formed by commercially available polyelectrolyte and oppositely charged surfactant would transform into a supramolecular film under a mild mechanical pressure, where the hydrophobic surfactant domains bridged by polyelectrolyte merge into hydrophobic mesophases to reduce interfacial energy. The hydrophobic mesophase will greatly retard water diffusion inside the film, so that a humidity gradient is generated as the film is exposed to a humid environment. The film will bend upward automatically in touch with moisture skin, and the bending degree is proportional to the skin moisture status. Therefore, the film can be used as portable smart power‐free skin moisture sensor.

Abstract Across a city, tree communities are spatially heterogenous and vary by land use type. However, it remains unclear how urban tree communities change over time and whether rates of change depend on land use type. To address this knowledge gap, we analyzed urban tree composition using long‐term plot data to examine tree diversity changes across six different urban land use types in 1999, 2004, 2009, and 2014. We found that spatial differences in tree species diversity and community composition among land uses were much greater than changes over time. Number of trees increased over time, being driven by gains of non‐native species. There was also a significant interaction between land use and time, with institutional and transportation land uses having greater community changes over time. Our study can inform site‐specific efforts to promote and preserve urban biodiversity across public and private land uses.

Abstract The tumor microenvironment (TME) is a biological system with sophisticated constituents. In addition to tumor cells, tumor‐associated macrophages (TAMs) and microbiota are also dominant components. The phenotypic and functional changes of TAMs are widely considered to be related to most tumor progressions. The chronic colonization of pathogenic microbes and opportunistic pathogens accounts for the generation and development of tumors. As messengers of cell‐to‐cell communication, tumor‐derived extracellular vesicles (TDEVs) can transfer various malignant factors, regulating physiological and pathological changes in the recipients and affecting TAMs and microbes in the TME. Despite the new insights into tumorigenesis and progress brought by the above factors, the crosstalk among tumor cells, macrophages, and microbiota remain elusive, and few studies have focused on how TDEVs act as an intermediary. We reviewed how tumor cells recruit and domesticate macrophages and microbes through extracellular vehicles and how hijacked macrophages and microbiota interact with tumor‐promoting feedback, achieving a reciprocal coexistence under the TME and working together to facilitate tumor progression. It is significant to seek evidence to clarify those specific interactions and reveal therapeutic targets to curb tumor progression and improve prognosis.

Tanshinone IIA (TanIIA) is the main active ingredient in the fat-soluble components isolated from Salvia miltiorrhiza Bunge. Our previous studies have convincingly proved that TanIIA is an effective drug against human colorectal carcinoma cells. In order to further demonstrate the effect of TanIIA on CRC, we carried out exploratory research about it in vivo and in vitro. The results demonstrated that TanIIA were observably more effective than control group in preventing tumor growth, and it has increased the survival time. Cancer cells viability and proliferation were accompanied by concentration and time dependent decline reached with TanIIA. We found that TanIIA altered the morphology of cytoskeleton and it could obviously induce apoptosis of colorectal cancer cells and block the cells in the G0/G1 phase. TanIIA also increased phosphorylation of p38MAPK, upregulated ATF-2 expression and downregulated Transgelin-2 expression, which could be reversed by SB203580, a p38MAPK-specific inhibitor. Our results suggested that TanIIA could induce apoptosis of colorectal cancer and block the cells in G0/G1 phase involved in downregulating the expression of Transgelin-2 through p38MAPK signal pathway.

Residues of neonicotinoid pesticides have potential risks to food, environmental and biological safety. In this study, the hapten toward imidacloprid was adopted to gain antibodies. After molecular modeling, the electrostatic potentials of eight commonly-used neonicotinoid pesticides were individually calculated to analyze the structural similarity. Two representative compounds (imidacloprid and acetamiprid) with moderate similarity were rationally selected for hybridoma screening. Using this strategy, four clones of broad-specific monoclonal antibodies (mAbs) against multiple neonicotinoids were obtained, and the clone 6F11 exhibited the broadest spectrum to six neonicotinoid pesticides and two metabolites, with half-maximal inhibitory concentrations (IC50) ranging from 0.20 to 5.92 ng/mL. Then, the novel antibody gene was sequenced and successfully expressed in full-length IgG form using mammalian cells. Based on the sensitive recombinant antibody, a gold lateral-flow immunosensing strip assay was developed and it was qualified for rapid detection of imidacloprid, clothianidin or imidaclothiz residues in food samples.

Known as “living fossils”, large old trees play an important role in ecology, landscape, and culture and are an important part of ecosystems and human settlements. The aim of this paper is to provide suggestions for the protection of urban large old tree resources and the selection of large old tree backup resources. First, we conducted a statistical analysis on the composition, distribution, and important values of large old tree species in Beijing and used Downtrend correspondence analysis (DCA) to analyze the composition of different types of habitat tree species. Second, we created a 3 km × 3 km grid within the administrative scope of Beijing, extracted the number of large old trees and tree species richness in the grid, and used geographic detectors to determine the driving factors of the spatial distribution of large old trees, as well as tree species richness differences and their interactions. A total of 40,590 large old trees in Beijing were found, belonging to 72 species, 52 genera, and 29 families. Platycladus orientalis (L.) Franco was the dominant tree species, with an importance value of 0.51. Among the different habitats, the large old trees were found in parks and temples, and the greatest tree species number of old trees were found in communities and the countryside; meanwhile, microgreen spaces had the lowest number of trees and tree species. The distribution of large old trees and tree species was mainly concentrated in the center of the city and the northwest. The distribution pattern of large old tree resources in Beijing is affected by the interaction of various factors. Social factors were the dominant in the distribution of large old tree resources in Beijing. The spatial distribution of large old trees was mainly affected by the scenic resort and historic site (SRHS), and the SRHS and gross domestic product (GDP) level were the most important factors influencing the richness of large old tree species. In addition, the functional value and characteristics of tree species determined the distribution of large old tree habitats. Therefore, the protection of large old tree resources requires developing scientific management and planning by managers, increasing investment in management and protection, and strengthening ecological culture publicity.

The toxicity of clothianidin to non-target organisms has gradually attracted world-wide attention. It is essential to develop reliable methods for the on-site detection of clothianidin residue. In this study, analogue-based heterologous ic-ELISAs were designed to rapidly screen desirable hybridomas, which could be used for the construction of recombinant antibodies (RAbs) against clothianidin. Based on the antibody variable region genes, two full-length IgG RAbs (1F7-RAb and 5C3-RAb) were produced by the mammalian cell expression system. The performance of the two RAbs was characterized and compared by heterologous ic-ELISAs and non-competitive surface plasmon resonance (SPR) assays. Using heterologous ic-ELISAs, the 1F7-RAb exhibited highly specific and sensitive recognition to clothianidin with an IC50 of 4.62 μg/L, whereas the 5C3-RAb could bind to both clothianidin and dinotefuran. The results of the non-competitive SPR assay further verified that the 1F7-RAb had a higher specificity and affinity to clothianidin than the 5C3-RAb. Finally, a gold immunochromatographic assay based on the novel antibody, 1F7-RAb, was developed for rapid detection of clothianidin with high sensitivity (visual detection limit of 2.5 μg/L), specificity, and good reproducibility, which can be used as an effective supervision tool for clothianidin residue in agricultural and environmental samples.