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Forest inventory data (FID) are important resources for understanding the dynamics of forest carbon cycling at regional and global scales. Developing carbon storage growth models and analyzing the difference and climate effect on carbon sequestration capacity have a great importance in practice, which can provide a decision-making basis for promoting high-quality development of forestry and implementing the carbon emission peak and carbon neutralization strategy. Based on the carbon storage dataset of 2680 sample plots from the ninth national forest inventory (NFI) of China, the carbon storage growth models and climate-sensitive variable-parameter carbon storage growth models for three major coniferous plantations (Larix spp., Pinus massoniana, and Pinus tabuliformis) were developed by using weighted nonlinear regression method. The effects of two climate factors (mean annual temperature (MAT) and mean annual precipitation (MAP)) on carbon storage growth and carbon sequestration capacity were analyzed and compared. The mean prediction error (MPE) of carbon storage growth models for three major coniferous plantations was less than 5%, and total relative error (TRE) was approximately less than 2% for self- and cross- validation. The maximum current annual increment of carbon storage for P. massoniana, Larix, and P. tabuliformis was 2.29, 1.89, and 1.19 t/(ha·a), respectively, and their corresponding age of inflection point was 9a, 14a, and 30a, respectively. The maximum average increment of carbon storage for P. massoniana, Larix, and P. tabuliformis was 1.85, 1.50, and 0.94 t/(ha·a), respectively, and their corresponding age of quantitative maturity was 16a, 24a, and 53a, respectively. The maximum average increment of carbon storage for the P. massoniana and Larix plantations was approximately 1.97 and 1.60 times, respectively, that of P. tabuliformis plantation. The average increment of carbon storage for the P. massoniana and Larix plantations reduced approximately by 4.5% and 3.8%, respectively, when the MAT decreases by 1 °C. The average increment of carbon storage for the Larix and P.tabuliformis plantations decreased by approximately 6.5% and 3.6%, respectively, when the MAP decreases by 100 mm. Our findings suggest that: the carbon sequestration capacity is from highest to lowest in the P. massoniana, Larix, and P. tabuliformis forests. MAT and MAP have different effects on the carbon growth process and carbon sequestration capacity of these plantations. The greatest impact on carbon sequestration capacity was detected in the Larix plantation, followed by the P. massoniana and P. tabuliformis plantations. It is essential to coordinate regional development and employ scientific management strategies to fully develop the maximum carbon sequestration capacity in terms of plantations in China. In the present study, we estimate the carbon storage in major coniferous plantations in China and describe a useful methodology for estimating forest carbon storage at regional and global levels.

Biofluorescence imaging enables real-time, visual detection of biomolecules, cells and tissues/organs on a three-dimensional scale. And it can track the various physiological processes of the organism and understand the relationship between biomolecules and their structure and function. Near-infrared imaging has a high temporal and spatial resolution, low damage to biological tissues and strong penetrating capability, good sensitivity and low background fluorescence interference, which are the advantages of imaging technology. However, at present, the deficiencies of fluorescent groups include relatively low fluorescence quantum yield and unfavorably short emission wavelength in the NIR region, especially in the second near-infrared window (1000–1700 nm, NIR-II). In the in vivo processes and applications of NIR fluorescence materials, biocompatibility, fluorescence quantum efficiency and adjustability of excitation and emission wavelengths in the NIR region should be considered. Therefore, organic polymeric materials are ideal for the construction of the NIR fluorescence probe. In this review, the synthesis and applications of NIR fluorescence polymers were summarized and the future trend has prospected as well.

Background Allergic rhinitis (AR) is a common immunoglobulin E-mediated immune response involved various cell types, while the role of nasal fibroblasts (NFs) in the pathogenesis of AR is less understood. Purpose The study aimed to uncover the gene expression profile of AR-derived NFs and the potential mechanism for the changed phenotype of AR-NFs. Research Design The primary NFs were isolated from 3 AR patients (AR-NFs) and 3 controls (Ctrl-NFs), and the proliferation, migration and interleukins production abilities of NFs were detected respectively. RNA-sequence was used to identify differentially expressed genes (DEGs) in AR-NFs. Transcription factor (TF) regulatory network and bioinformatic analyses were both conducted to clarify the biological roles of DEGs including the TFs. The DEG with the highest validated |fold change (FC)| value, detected by qPCR, was selected for further confirmation. Results AR-NFs showed a higher proliferation and migration abilities as well as released higher levels of IL-33 and IL-6, compared to Ctrl-NFs. A total of 729 DEGs were screened out in AR-NFs. TF regulatory network indicated that BARX homeobox 1 (BARX1) and forkhead box L1 were the major node TFs. Bioinformatic analyses showed that a large number of DEGs including several target genes of BARX1 were both enriched cytokine-related GO terms, and immune- or inflammation-related pathways. BARX1 had the highest |FC| value, and silencing BARX1 in AR-NFs resulted in the significant downregulation of proliferation and migration abilities, and the production of interleukins. Conclusions Our study for the first time provided the gene expression profile of AR-derived NFs, and BARX1 could be developed as a potent target to alleviate the pathogenesis of AR.

Background: Allergic rhinitis (AR) is a common immune disease of the nasal mucosa characterized with immunoglobulin E (IgE)-mediated allergic inflammation after exposure to allergens in susceptible population. Previous reports have demonstrated that the bone marrow mesenchymal stem cells (BMSCs) could reduce allergic inflammation. However, there is little knowledge about whether the culture supernatant of BMSCs (conditioned medium, CM) has similar anti- inflammatory potential in treating AR. Objective: The study aimed to evaluate the immunoregulatory effects of conditioned medium derived from BMSCs (BMSC-CM) on allergic inflammation in an AR mouse model. Material and Methods: The AR murine model was induced by repeated sensitization and challenges with ovalbumin (OVA). Subsequently the allergic symptoms of AR mice, cytokine levels, the histopathological features of the nasal mucosa and T helper 1 (Th1) : T helper 2 (Th2) cells ratio were evaluated. Results: Treatment with BMSC-CM was found as effective as BMSCs in reducing allergic symptoms and inhibiting eosinophilic infiltration in the nasal mucosa. After BMSC-CM or BMSCs administration, the OVA-specific IgE and interleukin 4 levels in serum decreased and interferon gamma level increased compared with AR mice treated with uncultured fresh medium. Flow cytometry analysis revealed a decrease in Th1:Th2 cells ratio after OVA-sensitization and the ratio was reversed by BMSC-CM and BMSCs treatments. Furthermore, the data revealed that BMSC-CM suppressed the production of signal transduction and activator of transcription 6 (STAT6) at messenger RNA and protein levels in the nasal mucosa. Conclusion: BMSC-CM could ameliorate allergic inflammation and regulate the balance of Th cells, and the underlying mechanism was closely related to STAT6 signaling pathway. The immunoregulatory effects of BMSCs could be achieved through paracrine function, and nasal dripping of BMSC-CM might be a novel approach for the treatment of AR.

Epithelial-myoepithelial carcinoma (EMC) is a rare malignant salivary gland tumor that occurs mostly in the parotid gland. We report a case of EMC of the submandibular gland in a young man. The patient was aware of a slow-growing mass in the right submandibular gland for 1 year. Clinical examination and ultrasound confirmed a right submandibular mass, 2.5 × 3 cm2 in size. Ultrasound-guided fine-needle aspiration indicated a diagnosis of pleomorphic adenoma, which was also suggested by magnetic resonance imaging. The submandibular gland tumor was excised. Immunohistochemical analysis showed carcinoma ex pleomorphic adenoma with a major epithelial-myoepithelial component. The patient was not treated with radiotherapy after surgery. No recurrence was observed during 24 months of follow-up. Because the morphology of EMC is similar to that of a benign tumor, it is frequently initially misdiagnosed. Surgery is always the most effective diagnostic and therapeutic measure for salivary gland tumors, especially those that grow slowly. Resection with negative margins is the treatment of choice for EMC; use of adjuvant radiotherapy is controversial.

Background: Bone marrow mesenchymal stem cells can promote the recovery of immune balance and regulate the balance of Th1/2 cells. Allergic rhinitis is a disease with Th1/2 imbalance mediated by IgE. It’s unclear whether BMSCs could regulate AR disease. In this study, the possible role of BMSCs was explored. Methods : AR mouse model was established by ovalbumin (OVA). 18 models were randomly divided into three groups: AR-sensitized, Stem-cell-returned, Medium-returned; six unsensitized mouses named normal-control. IgE, IL-4 and INF-γ levels were measured by Elisa. Observing migration of BMSCs by immunofluorescence. Flow cytometry used to detect changes of Th1/2. STAT 4/6 protein level was detected by Western-blot. Results : After OVA-sensitization, IgE, IL-4 and STAT6 levels were higher, INF-γ and STAT4 level was lower. Flow cytometry revealed a decrease in Th1 cell and an increase in Th2 cell in AR group. After BMSCs treatment, t IgE, IL-4 and STAT6 levels in SCRg and MRg were lower than that in AR group, and tINF-γ and STAT4 level were higher than hat inAR group. Flow cytometry showed that the content of Th1 cell increased while Th2 cell decreased. Conclusions: BMSCs return treatment could decrease the expression of IL-4, promote the expression of INF-γ and regulate the balance of Th cell, and the mechanism was closely related to STAT4/6 signaling pathway. However there was no statistical difference between SCRg and MRg, so the role of BMSCs maybe achieved through paracrine function rather than multi-directional differentiation potential.

This study introduces an algorithm for video denoising based on improved dual-domain filtering and 3D block matching. The wavelet thresholding based on 3D block matching is introduced to make full use of the correlation of video sequence in order to apply dual-domain filtering to the video. A layered approach is used that attempts denoising in both a base layer and a detail layer. The result of wavelet thresholding based on 3D block matching is used as a guide image to make the base layer smoother. Shrinkage of short-time Fourier transform coefficients further decreases the noise in the detail layer. Experimental results show that the authors' algorithm generates a better base layer and detail layer than the traditional dual-domain filtering algorithms. The subjective and objective comparisons of different algorithms also prove that the proposed algorithm performs better for video denoising.

Based on the pilot ecosystem analysis of Qianjiangyuan National Park, the ecosystem services function value index system was determined, multiple methods such as market value method and shadow engineering method were used to evaluate the four major categories in the years 2005, 2010, 2015, and 2018 of the ecological services of Qianjiangyuan national park which are provision, regulation, culture, and support. Results show that the total value of the pilot ecosystem services in Qianjiangyuan national park had increased to 7430.11 × 106 yuan, 9128.41 × 106 yuan, 12,718.38 × 106 yuan, and 15,539.99 × 106 yuan for each category respectively. The regulation category has always been the core ecosystem services function in the national park, accounting for more than 40% of the value of the total services. The increase in the value of ecosystem services in the park was due to the implementation of ecological measures such as logging bans and people paying more attention to environmental protection.

The aim of this study was to examine the effect of shear mixing speed and time on the mechanical properties of graphene nanoplatelet (GNP) composites. Shear mixing is cited in the literature as one method of making a good dispersion of nanofillers in a polymer that breaks down agglomerates into smaller particles and in the case of GNP can exfoliate layers of graphene. In this paper 0.1 to 5 wt% GNP was mixed with epoxy at different speeds and for different lengths of time. The composites were then cured and the tensile strength and Young’s modulus was measured. Optical microscopy was performed to examine the dispersion of the GNP in the epoxy. The results show that the shear mixing speed and time affect the size of agglomerates, which has an impact on the mechanical properties of the composite. At 3000 rpm and 2 h of mixing the average size of agglomerate was 26.3 μm (30 % reduction compared to that of 1000 rpm and 1 h duration), the tensile strength of epoxy was not affected by the addition of GNP, while a 12 % increase was recorded for the Young’s modulus. It is also found that functionalisation of the surface of the GNP improves the bond formed between the GNP and the resin that enhances its mechanical properties with no effect on the size of the agglomerates. Acetone was used to improve the GNP dispersion and found that shear mixing 5 wt% of GNP with acetone increases the Young’s modulus up to 3.02 from 2.6 GPa for the neat epoxy, an almost 14 % rise.

Understanding the ecological processes that regulate microbial community assembly in different habitats is critical to predict microbial responses to anthropogenic disturbances and environmental changes. Rubber (Hevea brasiliensis) and Eucalypt (Eucalyptus urophylla) plantations (thereafter RP and EP) are rapidly established at the expense of forests in tropical China, greatly affecting tropical soils and their processes. However, the assembly processes of soil microbial communities after forest conversions remain unclear. We investigated soil microbial communities&rsquo, attributes and quantified the portion of deterministic assembly variation in two RP (a 3- and a 5-year-old) and two EP (a 2- and a 4-year-old) in Southern China. Shannon and Faith&rsquo, s Phylogenetic &alpha, diversity of both bacterial and fungal communities were higher in RP than in EP, regardless of plantation age or soil depth (0&ndash, 50 cm). Bacterial and fungal community structure was significantly different among the four plantations. The dominant microbial taxa in RP closely tracked the availability of nitrogen, phosphorus and potassium (K) while those in EP were closely related to the high total K content. Microbial co-occurrence networks in RP were more modular than those in EP, as governed by more keystone taxa that were strongly dependent on soil available nutrients. Environmental filtering imposed by soil nutrients heterogeneity contributed a considerable portion (33&ndash, 47%) of bacterial assembly variation in RP, but much less (8&ndash, 14%) in EP. The relative contribution of environmental selection on fungal assembly was also greater in RP than in EP. Our findings suggest that in RP clear microbial community patterns exist with respect to soil nutrients, whereas in EP microbial community assembly patterns are more stochastic and variable. The large variation in soil microbial community assembly patterns in EP could lead to fragile and unstable microbial-soil relationships, which may be one factor driving soil degradation in EP.

Additional file 3: Table S3. Nucleotide diversity (Pi) values and total number of mutation (Eta) in Phoebe.