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Natural organic nanoparticle cellulose nanocrystals (CNCs) with good biocompatibility and unique physical and chemical properties have been proved to be promising materials for drug delivery system...

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.

The development of bioimaging technology in recent years has shown that second near-infrared (NIR-II) fluorescence imaging (FI) is gradually replacing the traditional visible light and first near-infrared (NIR-I) FI. In the NIR-II window, the light absorption, autofluorescence and scattering of biological tissues are significantly reduced, which strongly promotes the design, development and application of contrast agents with NIR-II emission capabilities. However, the NIR-II bioimaging technology is still incomplete, in the initial stage, and has high research value. In order to increase the quantum yield (QY) of D–A polymers, we used thiophene, 3-methoxythiophene, 3,4-ethylenedioxythiophene (EDOT), 3-hexylthiophene and 3-(2-ethylhexyl)thiophene as strong electron donors and designed and synthesized NIR-II organic polymers P1, P2, P3, P4 and P5, which are of great significance to the molecular design of D–A conjugated polymers. Finally, we explored the FI of the polymers in vivo and in vitro, and verified our idea of increasing the QY.

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.

Fluorescence imaging (FI) and photoacoustic imaging (PA) play important roles in the real-time assessment of cell-based therapies. However, the limitations of conventional organic fluorescence contrast agents and the narrow range of the emission wavelength in the first near-infrared (NIR-I) window (750-900 nm) hamper applications of fluorescence imaging in living subjects. Herein, we report the design and synthesis of a short-wave infrared FI contrast agent and PA contrast agent based on a conjugated polymer-poly{2,5-bis[(5-thiophen-2-yl)methylene]-3,6-bis(2-octyldodecyl)-2,5-dihydropyrazine}-and its use to construct multifunctional nanoparticles to simplify photothermal therapy.

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.

Global education industry informatization wave with the maturing of the cloud computing force, the introduction of cloud computing is to promote the school education informatization transformation. Through the analysis of computer resources update is difficult and high cost, inconvenience unified management and maintenance, and low resource utilization, and the traditional information system itself cannot be Shared, low security, defects such as high energy consumption. To solve the above problems, FusionSphere, Huawei’s commercial version cloud platform based on open source OpenStack technology, is used to build the private cloud of Mandarin Education. Improve the utilization of traditional IT facilities through virtualization technology. The backup solution, eBackup, is designed to ensure the security and reliability of school information data and IT system. ServiceCenter and Operation Center technologies are used to realize the unified management, operation and maintenance of the cloud platform, which is convenient for unified management and maintenance. Customize the desktop cloud client to use the unified Office, deploy the "One Teacher, One Excellent Class" network teaching platform of Mandarin University, etc. The significance of the construction of Mandarin Education Cloud lies in solving the practical application problems of Mandarin Education Informatization.

In the electric power spot market, input data quality is critical to an accurate and reliable clearing result. Missing and abnormal data will lead to the result that the clearing algorithm diverges or the results mismatch reality. This would seriously affect power system security and reduce the efficiency of the market. Therefore, to ensure a smooth convergence of the algorithm and reasonable results, this paper proposes a rule-based verification method for the input data in the power spot market. Data integrity and logical verification rules are established. During the verification process, information will be divided into different warning levels and displayed so that users can modify relevant data according to the actual situation.

Objective: This study aimed to evaluate the outcomes of endoscopic optic nerve decompression (EOND) for adults with traumatic optic neuropathy (TON) and seek factors that might affect surgery outcomes. Methods: From January 2016 to June 2019, 16 adults diagnosed with TON, who underwent endoscopic trans-ethmosphenoid optic canal decompression, were reviewed. All the patients were treated with steroids before the surgery. The main outcome measure was an improvement in visual acuity (VA) after treatment. Results: Eight (50.0%) patients had residual vision before the surgery, while eight (50.0%) had no light perception. After surgical decompression, partial recovery of VA was achieved in three (18.75%) patients who were operated within 10 days and had residual vision before the surgery. However, no improvement in VA was observed for the remaining patients (81.25%) who were operated more than 10 days after injuries. Conclusions: EOND is beneficial for TON not responding to steroid therapy and can prevent permanent disability if earlier intervention is done prior to irreversible damage to the nerve. Endoscopic optic nerve surgery can decompress the traumatic and edematous optic nerve with proper exposure of optic canal and orbital apex without any major complications. The operation timing and residual vision are important factors affecting outcomes.

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.

Background Phoebe (Lauraceae) comprises of evergreen trees or shrubs with approximately 100 species, distributed in tropical and subtropical Asia and Neotropical America. A total of 34 species and three varieties occur in China. Despite of economic and ecological value, only limited genomic resources are available for this genus. Results We sequenced the two complete chloroplast (cp) genomes of Phoebe chekiangensis and P. bournei using Illumina sequencing technology via a combined strategy of de novo and reference-guided assembly. We also performed comparative analyses with the cp genomes of P. sheareri and P. sheareri var. oineiensis previously reported. The chloroplast genomes of P. chekiangensis and P. bournei identically contain 112 genes consisting of 78 protein coding genes, 30 tRNA genes, and 4 rRNA genes, with the size of 152,849 and 152,853 bp, respectively. From the two chloroplast genomes, 131 SSRs were identified and 12 different SSRs located in five protein coding genes. The analysis showed the extremely conserved structure of chloroplast genomes with surprisingly little variations at the LSC/IR and SSC/IR boundaries. Moreover, the mean nucleotide diversity was found to be 0.162% for 77 regions, suggesting an extraordinarily low level of sequence divergence. Four highest divergent regions (trnH-psbA, rps14-trnT, petA-psbJ, ccsA-ndhD) with the percentage of nucleotide diversity higher than 0.50% were identified, which had potential use for species identification and phylogenetic studies. Conclusion This study will facilitate our understanding of population genetics, phylogenetic relationship and plant evolution of Phoebe species. Electronic supplementary material The online version of this article (doi:10.1186/s40529-017-0192-8) contains supplementary material, which is available to authorized users.

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.

Owing to the fascinating properties of graphene, fulfilling the promising characteristics of graphene in applications has ignited enormous scientific and industrial interest. Chemical vapor deposition (CVD) growth of graphene on metal substrates provides tantalizing opportunities for the large-area synthesis of graphene in a controllable manner. However, the tedious transfer of graphene from metal substrates onto desired substrates remains inevitable, and cracks of graphene membrane, transfer-induced doping, wrinkles as well as surface contamination can be incurred during the transfer, which highly degrade the performance of graphene. Furthermore, new issues can arise when moving to large-scale transfer at an industrial scale, thus cost-efficient and environment-friendly transfer techniques also become imperative. The aim of this review is to provide a comprehensive understanding of transfer-related issues and the corresponding experimental solutions and to provide an outlook for future transfer techniques of CVD graphene films on an industrial scale.

Climate change has increased the need of information on amount of forest biomass. The biomass and carbon storage for larch (Larix spp.) in large geographic regions in China were failed to be accurately estimated from current biomass equations, because they were usually based on a few sample trees on local sites, generally incompatible to volume estimation, and not additive between components and total biomass. China needs reliable biomass estimation of the important species in the whole country. This study was based on the mensuration data of above- and belowground biomass from 600 and 198 destructive sample trees of larch from four regions in China, respectively. The main purpose was to develop compatible individual tree equations on both national and regional levels for above- and belowground biomass, biomass conversion factor and root-to-shoot ratio, using the nonlinear error-in-variable simultaneous equation approach. In addition, diameter at breast height (D) and tree height (H) growth models were also developed, and effects of key climate variables on biomass variation and growth process were analyzed. The results showed that mean prediction errors (MPEs) of regional aboveground biomass models were from 3.86 to 7.52%, and total relative errors (TREs) are within ±3%; and for regional belowground biomass equations, the MPEs are from 9.91 to 28.85%, and the TREs are within ±4%. The above- and belowground biomass and D- and H-growth were significantly related to mean annual temperature and mean annual precipitation. The biomass equations and growth models developed in this paper will provide good basis for estimating and predicting biomass of larch forests in China.

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.