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When fracturing a shale gas reservoir with supercritical CO2, the interaction between CO2 and shale will change the pore structure, thus affecting the mechanical properties of shale. To confirm the influencing mechanism of pore structure changes on mechanical properties, nuclear magnetic resonance, uniaxial compressive strength, and acoustic emission were performed on shale specimens from the Sichuan Basin before and after CO2 saturation. Results indicated that after CO2 saturation, the proportion of micropores and mesopores decreased, while the proportion of macropores increased, and both the uniaxial compressive strength and Young's modulus decreased. The effect of supercritical CO2 was more significant than that of gaseous CO2. The changes in the proportions of main aperture (10–50 nm) and macropores (>250 nm) are the main factors controlling shale's mechanical properties. The probability of a large-energy acoustic emission event is increased when shale specimen fails after CO2 saturation, indicating larger macropores volume proportion is more likely to produce large-energy acoustic emission events. Additionally, 12.84% of the proppant embedment and 29.34% of the fracture closure were caused by mechanical properties deterioration. The fracturing process should be optimized to reduce the negative effects of the mechanical properties deterioration in the development of shale gas with supercritical CO2.

The basic helix-loop-helix (bHLH) transcriptional regulatory proteins are key players in a wide array of developmental processes and abiotic stress responses. The bHLH domain has been identified an...

In order to study the source of heavy metal pollution in Baiyangdian Lake, laser-induced breakdown spectroscopy technology was used to analyze Fe, Cu, Cd, Pb, Zn, Cr, Ni, and As elements in the wetland bottom mud and fish gills of the lake. The methods of correlation analysis, principal component analysis, and cluster analysis are combined to analyze the characteristic spectra of heavy metal elements in the wetland bottom mud and fish gills. Research results show that the pollution sources of Longwangdian, Maidian, Wangjiazhai, and fish gills can be classified into three types. The first pollution source of Longwangdian is Fe, Cd, Pb, and As. The second is Ni, Zn, and Cu. The third is Cr. The first pollution source of Maidian is Fe, Cd, Zn, and Cr. The second is Cu, Pb, and As. The third is Ni. The first pollution source of Wangjiazhai is Fe, Cd, As, Cr, and Cu. The second is Ni and Zn. The third is Pb. The first pollution source of fish gills is Fe, Cd, Zn, Cr, Ni, and As. The second is Pb. The third is Cu. The similarity of heavy metal sources between fish gills and Maidian is higher than that of the other two wetlands. It is determined that the heavy metals in fish gills come from the bottom mud of Maidian. The research results can provide a basis for ecological protection and heavy metal pollution prevention and control in Baiyangdian Lake.

Corn (Zea mays L.) is a very important cereal crop and serves as food, feed, and industrial material (Liu et al. 2016). The root-lesion nematode (RLN) is considered one of the most important plant-...

Cucurbit chlorotic yellows virus (CCYV) is a cucurbit-infecting crinivirus. RNA silencing can be initiated as a plant defense against viruses. Viruses encode various RNA silencing suppressors to counteract antiviral silencing. P22 protein encoded by RNA1 of CCYV is a silencing suppressor, but its mechanism of action remains unclear. In this study, the cucumber ribosomal-like protein CsRPS21 was found to interact with P22 protein in vitro and in vivo. A conserved CsRPS21 domain was indispensable for its nuclear localization and interaction with P22. Transient expression of CsRPS21 in Nicotiana benthamiana leaves interfered with P22 accumulation and inhibited P22 silencing suppressor activity. CsRPS21 expression in N. benthamiana protoplasts inhibited CCYV accumulation. Increasing numbers of ribosomal proteins are being found to be involved in viral infections of plants. We identified a P22-interacting ribosomal protein, CsRPS21, and uncovered its role in early viral replication and silencing suppressor activity. Our study increases knowledge of the function of ribosomal proteins during viral infection.

Apoptosis, a type of programmed cell death, plays crucial roles in various physiological processes, from development to adaptive responses. Key features of apoptosis have been verified in various fungal microbes but not yet in Fusarium species. Here, we identified 19 apoptosis-related genes in Fusarium pseudograminearum using a genome-wide survey. Expression profile analysis revealed that several apoptosis-related genes were significantly increased during conidiation and infection stages. Among these is FpBIR1, with two BIR (baculovirus inhibitor-of-apoptosis protein repeat) domains at the N-terminal end of the protein, a homolog of Saccharomyces cerevisiae BIR1, which is a unique apoptosis inhibitor. FpNUC1 is the ortholog of S. cerevisiae NUC1, which triggers AIF1- or YCA1-independent apoptosis. The functions of these two proteins were assessed by creating Δfpbir1 and Δfpnuc1 mutants via targeted gene deletion. The Δfpbir1 mutant had more cells with nuclear fragmentation and exhibited reduced conidiation, conidial formation, and infectivity. Correspondingly, the Δfpnuc1 mutant contained multiple nuclei, produced thicker and more branched hyphae, was reduced in conidiation, and exhibited faster conidial formation and higher infection rates. Taken together, our results indicate that the apoptosis-related genes FpBIR1 and FpNUC1 function in conidiation, conidial germination, and infection by F. pseudograminearum. IMPORTANCE The plant-pathogenic fungus F. pseudograminearum is the causal agent of Fusarium crown rot (FCR) in wheat and barley, resulting in substantial yield losses worldwide. Particularly, in the Huanghuai wheat-growing region of China, F. pseudograminearum was reported as the dominant Fusarium species in FCR infections. Apoptosis is an evolutionarily conserved mechanism in eukaryotes, playing crucial roles in development and cell responses to biotic and abiotic stresses. However, few reports on apoptosis in plant fungal pathogens have been published. In this study, we identified 19 conserved apoptosis-related genes in F. pseudograminearum, several of which were significantly increased during conidiation and infection stages. Potential apoptosis functions were assessed by deletion of the putative apoptosis inhibitor gene FpBIR1 and apoptosis trigger gene FpNUC1 in F. pseudograminearum. The FpBIR1 deletion mutant exhibited defects in conidial germination and pathogenicity, whereas the FpNUC1 deletion mutant experienced faster conidial formation and higher infection rates. Apoptosis appears to negatively regulate the conidial germination and pathogenicity of F. pseudograminearum. To our knowledge, this study is the first report of apoptosis contributing to infection-related morphogenesis and pathogenesis in F. pseudograminearum.

Defective amyloid-β (Aβ) clearance from the brain is a major contributing factor to the pathophysiology of Alzheimer’s disease (AD). Aβ clearance is mediated by macrophages, enzymatic degradation, perivascular drainage along the vascular basement membrane (VBM) and transcytosis across the blood–brain barrier (BBB). AD pathology is typically associated with cerebral amyloid angiopathy due to perivascular accumulation of Aβ. Heparan sulfate (HS) is an important component of the VBM, thought to fulfill multiple roles in AD pathology. We previously showed that macrophage-mediated clearance of intracortically injected Aβ was impaired in the brains of transgenic mice overexpressing heparanase (Hpa-tg). This study revealed that perivascular drainage was impeded in the Hpa-tg brain, evidenced by perivascular accumulation of the injected Aβ in the thalamus of Hpa-tg mice. Furthermore, endogenous Aβ accumulated at the perivasculature of Hpa-tg thalamus, but not in control thalamus. This perivascular clearance defect was confirmed following intracortical injection of dextran that was largely retained in the perivasculature of Hpa-tg brains, compared to control brains. Hpa-tg brains presented with thicker VBMs and swollen perivascular astrocyte endfeet, as well as elevated expression of the BBB-associated water-pump protein aquaporin 4 (AQP4). Elevated levels of both heparanase and AQP4 were also detected in human AD brain. These findings indicate that elevated heparanase levels alter the organization and composition of the BBB, likely through increased fragmentation of BBB-associated HS, resulting in defective perivascular drainage. This defect contributes to perivascular accumulation of Aβ in the Hpa-tg brain, highlighting a potential role for heparanase in the pathogenesis of AD. Supplementary Information The online version contains supplementary material available at 10.1186/s40478-021-01182-x.

In this paper, a multi-band fusion model to improve the performances of the super-continuum laser absorption spectrometer (SCLAS) of CO2 was proposed and demonstrated. Various concentrations of CO2 were measured by the super-continuum laser in the wavelength of 1425–1445 nm, 1565–1585 nm, and 1595–1615 nm, respectively, at 295 K and 1 atm. The method for derivation of CO2 concentration using the integrated area of spectrum peaks is proposed. Linear models of the CO2 concentration and the integrated area of the absorption peaks in different bands were established, which achieves R2 of 0.9947, 0.9937, and 0.9824, respectively. The measurement accuracy with the models is evaluated with the parameter of relative analysis error (RPD), which results in a of more than 2, indicating reasonable prediction ability of the models. In order to improve the accuracy of the single model, the models of the three bands are weighted and fused based on R2 and RMSE, respectively. One of the fusion models reduces the prediction error and improves the accuracy of the single model effectively by decreasing the maximum relative error from 3.4 to 1.2% for a single model. The experimental results show that SCLAS can measure the CO2 concentration under different environments. The multi-band fusion model proposed here is feasible for CO2 measurement, which provides a new idea and new method for the detection of gases.

Ether lipids are overexpressed in malignant tumor and play an important role in tumor process. Glioma is the most common malignant central nervous system tumor, and the content of ether lipids is higher than that of normal tissues. Alkylglycerone phosphate synthase (AGPS) is a key enzyme in the synthesis of ether esters and plays a vital role in maintaining the morphology and pathogenic properties of tumor cells. The cell proliferation and the content of tumor-related lipid such as monoalkylglycerol ether (MAGe), lysophosphatidic acid ether (LPAe), lysophosphatidylcholine ether (LPCe), lysophosphatidylethanolamine ether (LPEe), phosphatidyl inositol (PI), phosphatidylcholine (PC), and phosphatidylserine (PS) were suppressed after AGPS silencing in U251, H4, and TJ905 cells; however, heterogeneous nuclear ribonucleoprotein K (HNRNPK) could reverse the above phenomenon such as cellar proliferation and ether lipid secretion. We found that HNRNPK was the target protein of AGPS by coimmunoprecipitation and mass spectrometry assay and verified by western blot assay in U251 cells. It confirmed that AGPS and HNRNPK are coexpressed in the cellular nucleus by a confocal laser microscope. The main protein-protein interaction mechanism between AGPS and HNRNPK is hydrogen bond, conjugation bond, hydrophobic bond, and electrostatic force by computer simulation prediction.

Additional file 1. Supplementary Table 1: Primary antibodies used in this study. Supplementary Table 2: The middle temporalis gyrus of Alzheimer’s disease and Non-demented control obtained from the Netherlands Brain Bank (NBB). Supplementary Table 3: The CSF and plasma samples of Alzheimer´s disease patients and non-demented controls from the Netherlands Brain Bank (NBB).

Freezing tolerance is a significant trait in plants that grow in cold environments and survive through the winter. Apple (Malus domestica Borkh.) is a cold-tolerant fruit tree, and the cold tolerance of its bark is important for its survival at low temperatures. However, little is known about the gene activity related to its freezing tolerance. To better understand the gene expression and regulation properties of freezing tolerance in dormant apple trees, we analyzed the transcriptomic divergences in the bark from 1-year-old branches of two apple cultivars, “Golden Delicious” (G) and “Jinhong” (H), which have different levels of cold resistance, under chilling and freezing treatments. “H” can safely overwinter below −30 °C in extremely low-temperature regions, whereas “G” experiences severe freezing damage and death in similar environments. Based on 28 bark transcriptomes (from the epidermis, phloem, and cambium) from 1-year-old branches under seven temperature treatments (from 4 to −29 °C), we identified 4173 and 7734 differentially expressed genes (DEGs) in “G” and “H”, respectively, between the chilling and freezing treatments. A gene coexpression network was constructed according to this expression information using weighted gene correlation network analysis (WGCNA), and seven biologically meaningful coexpression modules were identified from the network. The expression profiles of the genes from these modules suggested the gene regulatory pathways that are responsible for the chilling and freezing stress responses of “G” and/or “H.” Module 7 was probably related to freezing acclimation and freezing damage in “H” at the lower temperatures. This module contained more interconnected hub transcription factors (TFs) and cold-responsive genes (CORs). Modules 6 and 7 contained C-repeat binding factor (CBF) TFs, and many CBF-dependent homologs were identified as hub genes. We also found that some hub TFs had higher intramodular connectivity (KME) and gene significance (GS) than CBFs. Specifically, most hub TFs in modules 6 and 7 were activated at the beginning of the early freezing stress phase and maintained upregulated expression during the whole freezing stress period in “G” and “H”. The upregulation of DEGs related to methionine and carbohydrate biosynthetic processes in “H” under more severe freezing stress supported the maintenance of homeostasis in the cellular membrane. This study improves our understanding of the transcriptional regulation patterns underlying freezing tolerance in the bark of apple branches.

C2H2 zinc finger transcription factors such as FlbC and Msn2, have broad regulatory roles in fungal growth and conidiation. In the present study, we cloned and characterized a C2H2 zinc finger transcription factor gene, FpCzf14, in the wheat pathogen Fusarium pseudograminearum. FpCzf14 was localized to the nuclei. The expression of FpCzf14 was significantly upregulated in conidia, suggesting that FpCzf14 might contribute to conidiation. Further analysis of the fpczf14-deleted mutant (Δfpczf14) demonstrated that it exhibited defect in conidiation, and this defect was restored in the complemented strain Δfpczf14-C expressing FpCzf14, demonstrating that FpCzf14 was essential for conidiation. Moreover, FpCzf14 was required for mycelial growth and pathogenicity of F. pseudograminearum. Microscopic observation results showed that Δfpczf14 produced only very few penetration pegs and invasive hyphae inside host tissues compared with WT and Δfpczf14-C. Additionally, results of reverse transcription quantitative PCR (RT-qPCR) showed that FpCzf14 regulated expression of several conidiation-related genes in F. pseudograminearum. In conclusion, FpCzf14, as a core regulatory gene in conidiation, provides new insights into the mechanism of conidiation in F. pseudograminearum.

Whitefly-transmitted begomoviruses are economically important plant pathogens that cause severe problems in many crop plants, such as tomato, papaya, cotton, and tobacco. Tomato yellow leaf curl virus (TYLCV) is a typical monopartite begomovirus that has been extensively studied, but methods that can efficiently control begomoviruses are still scarce. In this study, we combined artificial microRNA (amiRNA)-mediated silencing technology and clay nanosheet-mediated delivery by spraying and developed a method for efficiently preventing TYLCV infection in tomato plants. We designed three amiRNAs that target different regions of TYLCV to silence virus-produced transcripts. Three plant expression vectors expressing pre-amiRNAs were constructed, and recombinant plasmid DNAs (pDNAs) were loaded onto nontoxic and degradable layered double hydroxide (LDH) clay nanosheets. LDH nanosheets containing multiple pDNAs were sprayed onto plant leaves. We found that the designed amiRNAs were significantly accumulated in leaves 7 days after spraying, while the pDNAs were sustainably detected for 35 days after the spray, suggesting that the LDH nanosheets released pDNAs in a sustained manner, protected pDNAs from degradation and efficiently delivered pDNAs into plant cells. Importantly, when the LDH nanosheets coated with pDNAs were sprayed onto plants infected by TYLCV, both the disease severity and TYLCV viral concentration in sprayed plants were significantly decreased during the 35 days, while the levels of H2O2 were significantly increased in those plants. Taken together, these results indicate that LDH nanosheets loaded with pDNAs expressing amiRNAs can be a sustainable and promising tool for begomovirus control.

Soybean (Glycine max L.) is a very important commercial crop in China (Li et al. 2019). Pratylenchus coffeae (Zimmermann, 1898) Filipjev & Schuurmans Stekhoven, 1941, is one of the most important root-lesion nematodes that invade the roots of many crops. In August 2018, five root and soil samples were collected in a soybean field, near Xipan village in Linshu county of Linyi City, Shandong Province, China (Fig. S1), to investigate the occurrence of root-lesion nematodes. The collected plants (cv. Lindou No.10) were growing poorly and the roots showed distinct brown lesions (Fig. S2). Pratylenchus spp. were extracted using the modified Baermann funnel method for 2 days (Hooper et al. 2005). On average, 395 root-lesion nematodes per kg of soil and 36 root-lesion nematodes per gram of fresh roots were extracted. The extracted root-lesion nematodes were disinfected with 0.3% streptomycin sulfate and cultured on carrot disks for propagation at 25°C. The species identification was based on morphological and molecular criteria. Key morphological features were determined for females and males. Measurements of females (n = 16) included body length = 561.0 μm ± 37.6 (standard deviation) (520.5 to 654.0 μm), tail length = 30.0 μm ± 1.9 (27.0 to 33.5 μm), stylet = 16.0 μm ± 0.6 (15.0 to 17.5 μm), a = 28.2 ± 2.3 (23.7 to 31.5), b = 6.4 ± 0.5 (5.7 to 7.3), c = 18.7 ± 1.8 (15.7 to 23.8), and V = 80.8% ± 2.1 (76.5 to 83.8%). Measurements of males (n = 16): body length = 511.0 μm ± 28.1 (range= 475.5 to 566.0 μm), tail length = 26.0 μm ± 1.3 (23.5 to 28.5 μm), stylet = 15.0 μm ± 0.5 (14.5 to 16.0 μm), spicule length = 17.0 μm ± 0.9 (16.0 to 18.5 μm), a = 30.8 ± 1.5 (28.0 to 33.2), b = 6.1 ±0.4 (5.6 to 6.9), and c = 19.8 ± 1.3 (18.1 to 22.2) (Fig. S3). All the morphological features of this population matched the description of P. coffeae (Castillo and Vovlas, 2007). DNA was extracted from an individual female as described previously (Wang et al. 2011). The rDNA-internal transcribed spacer (ITS) region and the D2/D3 region of the 28S rRNA gene were amplified by primers 18S/26S (Vrain et al. 1992) and D2A/D3B (De Ley et al. 1999), respectively. The PCR products were purified and sequenced. The obtained sequences of the ITS region (1,253 bp) and the D2/D3 region of 28S rRNA (781 bp) were deposited in GenBank. The ITS sequences of the root-lesion nematode obtained in this study (GenBank Accession no. MT879294) exhibited 99% identity with several P. coffeae sequences available in the GenBank (e.g., KR106219, MT586756, KY424205, and MN749379), and the obtained D2/D3 region sequence (MT879295) exhibited 100% identity with several P. coffeae sequences (e.g., MT586754, MN750755, MK829009, and MH730447). Both morphological and molecular data confirmed the presence of P. coffeae. To confirm reproduction on soybean, the obtained root-lesion nematode population was used in a greenhouse (25°C) assay to fulfill modified Koch's postulates. About 20 days after sowing, eight pots, each with one soybean plant (Lindou No.10) were inoculated with 1000 P. coffeae. The inoculated plants were kept in 1.5 L pots containing 1.2 L sterilized soil. Eight pots of uninoculated soybeans were used as the control. Ten weeks later, the inoculated roots were washed and brown lesions were observed. The number of nematodes/pot was approximately 7360 in soil and 796 in roots, and the reproduction factor was 8.16. Root-lesion nematodes and symptoms were not observed in control groups. P. coffeae has only been reported on soybean in Zhejiang (Wei et al. 2013) and Henan Province (Li et al. 2019) of China. To our knowledge, this is the first report of P. coffeae infecting soybean in Shandong Province, China. Since the root-lesion nematode can cause considerable damage to soybean, care should be taken to prevent the spread of P. coffeae to other regions in China.

Immunoglobulin A nephropathy (IgAN), an autoimmune renal disease with complicated pathogenesis, is one of the principal reasons for end-stage renal disease in the clinic. Evidence has linked apparent alterations in the components of the microbiome and metabolome to renal disease in rats. However, thus far, there is insufficient evidence that supports the potential relationship between gut microbiome, circulating metabolites, and IgAN. This study was designed to probe the effects of IgAN on intestinal microecology and metabolic phenotypes and to understand the possible underlying mechanisms. Fecal and serum samples were collected from IgAN rats. Composition of the gut microbiota and biochemical changes in the metabolites was analyzed using 16S rDNA sequencing and untargeted metabolomics. The IgAN rats exhibited renal insufficiency and increased concentration of 24-h urine protein, in addition to deposition of IgA and IgG immune complexes in the kidney tissues. There was a disturbance in the balance of gut microbiota in IgAN rats, which was remarkably associated with renal damage. Marked changes in microbial structure and function were accompanied by apparent alterations in 1,403 serum metabolites, associated with the disorder of energy, carbohydrate, and nucleotide metabolisms. Administration of Zhen Wu Tang ameliorated microbial dysbiosis and attenuated the renal damage. Besides, treatment with Zhen Wu Tang modulated the metabolic phenotype perturbation in case of gut microbiota dysbiosis in IgAN rats. In conclusion, these findings provided a comprehensive understanding of the potential relationship between the intestinal microbiota and metabolic phenotypes in rats with IgAN. Elucidation of the intestinal microbiota composition and metabolic signature alterations could identify predictive biomarkers for disease diagnosis and progression, which might contribute to providing therapeutic strategies for IgAN.

Background: Multiple randomized controlled trials have shown that acupuncture (ACU) work well in the treating mammary gland hyperplasia, which has been widely used in hospitals of China. Although the choices of ACU treatments varies in practice, most are based on experience or preference. Therefore, we outline a plan to assess and rank the efficacy of the various ACU methods to formulate a prioritized regimen for mammary gland hyperplasia in ACU therapy. Methods: We will make a comprehensive retrieval in 7 databases as following: PubMed, Embase, Cochrane Library, China BioMedical Literature, China National Knowledge Infrastructure, Chinese Scientific Journals Database, and Wanfang database. The time is limited from the construction of the library to June 2020. We will evaluate the quality and the evidence of the included randomized controlled trials by the risk of bias tool and grading of recommendations assessment, development and evaluation, respectively. Bayesian network meta-analysis will be conducted using Stata16.0 and WinBUGS V.1.4.3. Results: The results of this study will be published in a peer-reviewed journal. Conclusions: Our study is expected to provide high-quality, evidence-based recommendations on further treatment of MGH for clinicians. Registration: PROSPERO (registration number CRD42020158743).

Background: Ankylosing spondylitis (AS) is a common progressive autoimmune inflammatory disease. Du moxibustion can effectively treat AS with few adverse reactions. The aim of this protocol is to systematically investigate the effectiveness and safety for management of AS with Du moxibustion. Methods: Seven relevant databases, namely, PubMed, Cochrane Library, Embase, Chinese Biomedical Literatures Database (CBM), China National Knowledge Infrastructure (CNKI), WangFang Database (WF), Chinese Scientific Journal Database (VIP) will be searched from their inception until May 1st, 2020. All clinical randomized controlled trials containing eligible interventions(s) and outcome(s) will be included, regardless of blinding or publication types. Two reviewers will independently retrieval databases, extract data, and then assess the quality of studies. Data synthesis will be conducted by RevMan 5.3 software. We regard the effective rate, Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Visual Analogue Scale (VAS) as the primary outcomes, and the secondary outcomes contain C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), finger-to-floor distance (FFD), occiput to wall distance (OWD), and side effects. The result about the curative effect and safety of Du moxibustion for AS will be presented as risk ratio for dichotomous data and mean differences with a 95% confidence interval for continuous data. Results: The finding will be presented in a journal or related conferences. Conclusions: This study expects to provide high-quality, evidence-based recommendations on further treatment for clinical guidance. PROSPERO registration number: CRD42020158727.

As the most important greenhouse gas, CO2 has caused a lot of climate change problems. Therefore, the measurement of CO2 is of great significance. Based on the tunable diode laser absorption spectroscopy (TDLAS), the effect of temperature on the absorption spectrum of CO2 was studied. A DFB laser with the center wavelength of 1430 nm was selected. The absorption line of CO2 near 1432 nm at different temperatures (293-373 K, interval 10K) was measured by wavelength modulation spectroscopy (WMS). By comparing S-G filtering method, FFT filtering method and P-F filtering method, the spectral data was preprocessed, and the optimal preprocessing method was determined. The measurement error caused by noise was reduced effectively, the second harmonic signal of CO2 at different temperatures was obtained, and the influence of temperature on the absorption spectrum of CO2 was analyzed. The goodness of fit of temperature and signal strength under different orders was evaluated. Finally, the second-order polynomial fitting was chosen as the optimal model of CO2. The experimental results complement and improve the existing database to ensure the accuracy of CO2 inversion, which has an important reference significance for the measurement of CO2 in practical applications.

In order to select more suitable characteristic lines as the analysis lines of the elements, laser-induced breakdown spectroscopy is used to detect the self-made soil sample doped with Cd and Fe elements. Using Savitzky-Golay convolution smoothing method to preprocessed spectral data. Select the common line Cd I: 288.122nm, 346.62 nm, Fe I: 357.001 nm, 363.146 nm to establish the calibration curve by external standard method, calculate the detection limit ， the influences of atomic configuration and angular momentum on the calibration curve and detection limit of the spectral transition level are studied. The study shows that the detection limit calculated by the analysis lines with high SNR are relatively low and more sensitive to the detection of elements; The SNR of the analysis lines with the same atomic configuration of the transition show the same trend with the change of element content. The analytical lines Cd I: 346.62 nm (2-1) and Fe I: 363.146 nm (4-3) with relatively large angular momentum are better excitation, and the correlation coefficient R2 of the obtained calibration curves are relatively higher, the limit of detection is smaller than the Cd I: 288.122 nm (1-1) and Fe I: 357.001 nm (1-1), the lines with large angular momentum are more suitable for element detection.

Geothermal extraction usually requires reservoir fracturing to realize economic exploitation and fluid flow in hot-dry rock fractures has become a research hotspot. In the present study, gas flow through shear and tensile granite fractures was investigated to comparatively study effect of fracture mesoscopic structure evolution on fracture hydro-mechanical characteristics under confining stress ranging from 1 to 40 MPa and inlet pressure ranging from 0.005 to 3.6 MPa. Four major findings are reported herein. First, the conductivity of shear fractures is much higher than that of tensile fractures and the ratio of the former to the latter can be up to around 265 under the stress of 40 MPa. The second finding was that the Z2 values of tensile fractures are higher than shear fractures, indicating that the fracture surface of tensile fractures is rougher and has more mesoscopic asperities. When the two surfaces get to contact, tip contact and stress concentration happen, resulting in higher deformation in tensile fractures. The cluster coefficient characterizes fracture contact cluster property. Higher cluster coefficient indicates lower fracture deformation and lower viscous loss. Shear fractures have higher cluster coefficient than that of tensile fractures so shear fractures are weakly deformable. However, high flow velocity and Reynolds number easily occur in shear fractures, so transitional and turbulent flow dominates in shear fractures while laminar and transitional flow in tensile fractures. Third, a mechanical model relates the average imbedded depth to loading stress and lacunarity, a hydraulic aperture model based on void space and lacunarity and a friction factor model based on Reynolds number and lacunarity were built, respectively, based on the experimental data. Then a nonlinear flow model was proposed. The fourth finding was that parametric analysis on the cluster coefficient shows that the higher the cluster coefficient, the lower of fracture deformation is and the higher of hydraulic aperture is. When the cluster coefficient is high, less viscous loss occurs; however, the fluid velocity may be high, so the friction factor will be high since more inertial loss happens.

Fungal pathogens cause serious crop diseases and decrease crop yields and quality. Polyacetylene alcohols are plant secondary metabolites and bioactive against various pathogenic fungi. They are, however, difficult to synthesize. In the present study, an efficient and highly enantioselective method (>98% ee) was established and employed to achieve the synthesis of the natural C18 polyacetylenes (S,E)-octadeca-1,9-dien-4,6-diyn-3-ol 1, (3R,10R,E)-octadeca-1,8-dien-4,6-diyne-3,10-diol 2, and their analogs. The title compounds were structurally characterized and biologically evaluated for fungicidal activities. The compounds exhibited high potencies against eight pathogenic fungal species tested, such as Colletotrichum gloeosporioiles, Bipolaris sorokiniana, Fusarium graminearum, and Fusarium pseudograminearum, with half-maximum effective concentrations ranging from 8 to 425 μg/mL, being similar to those of the fungicide thiophanate-methyl (3-408 μg/mL). These compounds are potential natural fungicides and fungicide lead candidates for further structural and property improvements.

Based on the meteorological data from 1952 to 2014, the changes of outdoor air design conditions in Beijing, Guangzhou, Haikou, Lhasa, and Shanghai were analyzed. The four parameters which are outdoor design temperature for heating, outdoor design temperature for ventilation in winter, outdoor design temperature for air conditioning in winter, and outdoor design average daily temperature for air conditioning in summer were calculated for each city with statistical 30 years and sliding one-year incremental method. Then, the trend of 60 years’ data of each city was analyzed respectively. The results show that over the past half century, the partial outdoor air design conditions for heating ventilation and air conditioning of civil buildings in China have been significantly increased, and the growth trend of conditions in each climate region has different characteristics.

Additional file 2: Table S1. Primers used in the study.

The heating and air conditioning energy consumption account for about 40–60% of the building energy consumption. The research on the relationship between building cooling and heating itemized load and meteorological parameters can further clarify the energy-saving potential of buildings and take concrete measures accordingly. In this paper, a full-year dynamic energy consumption simulation of office buildings was carried out using the typical meteorological year (TMY) generated independently, and the relationship between six meteorological parameters and gain-and-loss of windows and heat gain-and-loss of infiltration is analyzed. The purpose is to seek quantitative relationships between building cooling and heating itemized load and meteorological parameters using principle components analysis (PCA) method. The results show that the synthesis of several related meteorological parameters to represent the outdoor climate conditions has a significant correlation with the heat gain-and-loss of windows and heat gain-and-loss of infiltration, consistent with the analysis of the heat transfer mechanism of building physics. It has been well proven in office buildings, providing a new idea for predicting building energy consumption quickly and accurately.

Cereal cyst nematodes cause serious yield losses of wheat in Hunaghuai winter wheat growing region in China. Beauveria bassiana 08F04 isolated from the surface of cysts is a promising biological control agent for cereal cyst nematodes. As the colonization capacity is a crucial criteria to assess biocontrol effectiveness for a microbial agent candidate, we aimed to label B. bassiana 08F04 for efficient monitoring of colonization in the soil. The binary pCAM-gfp plasmid containing sgfp and hph was integrated into B. bassiana 08F04 using the Agrobacterium tumefaciens-mediated transformation. The transformation caused a significant change in mycelial and conidial yields, and in extracellular chitinase activity in some transformants. The cultural filtrates of some transformants also decreased acetylcholinesterase activity and the survival of Heterodera filipjevi second-stage juveniles relative to the wild-type strain. One transformant (G10) had a growth rate and biocontrol efficacy similar to the wild-type strain, so it was used for a pilot study of B. bassiana colonization conducted over 13 weeks. Real-time PCR results and CFU counts revealed that the population of G10 increased quickly over the first 3 weeks, then decreased slowly over the following 4 weeks before stabilizing. In addition, the application of wild-type B. bassiana 08F04 and transformant G10 significantly reduced the number of H. filipjevi females in roots by 64.4% and 60.2%, respectively. The results of this study have practical applications for ecological, biological and functional studies of B. bassiana 08F04 and for bionematicide registration.

Methyl thiol(CH3SH) is a colorless, flammable, smelly toxic gas. A large amount of methyl thiol gas comes from organic chemicals and agricultural production, and its olfactory threshold is very low (2ppb), which not only causes pollution to the environment, but also seriously affects people's quality of life and physical health. At the same time, methyl thiol also belongs to the human body of the endogenous trace volatile organic compounds (VOCs), and periodontitis disease is closely related. Therefore, the detection of methyl thiol is very important for the assessment of the environmental atmosphere and exhalation analysis. In this paper, the concentration of methyl thiol in the atmosphere was retrieved, simultaneously with methane and water vapor, by using artificial neural network (ANN) method based on wavelength modulation spectroscopy (WMS). A mid-infrared spectral band of 3392.4~3394.7 nm was selected to cover the absorption of the three gases, which can be available by tuning an interband cascade laser in our laboratory. In order to determine the concentrations of the three gases simultaneously from the measured WMS signal, the error back propagation (BP) ANN classification algorithm model was established by a series of simulation WMS signals. The second harmonic (2f) signal detection with WMS for different concentration ratios of the three gases under atmospheric conditions was simulated by means of the Hitran and PNNL databases. Of these, 450 groups were used as training samples and 60 sets of data as testing samples. Feature extraction of peak and valley and principal component analysis (PCA) methods were used to reduce the dimension of spectral signals. Then BPANN was trained, and best validation performance of network learning is 0.000241 at epoch 46. The average relative errors are 0.0047 and 0.000742, respectively when validating with testing samples by using the two dimensional reduction methods. The results prove the feasibility of these two methods and BPANN learning algorithm. Finally, the mixed spectral data of WMS-2f signal obtained from the actual experiment were fed into the established BPANN model. However, there are large deviations between the output results of the BPANN model and the actual concentration of the three gases. The relative deviation of methane, water vapor and methyl thiol are 88.92%, 1.69% and 59.94%, respectively. Because there is the background signal, including etalon signal, noise and residual amplitude modulation, superposed in the actual WMS-2f signal, which makes the poor consistency between the experimental data and the ideal simulation data. Overall, the measurement model can be used for qualitative analysis of the actual mixed gases detection. The accuracy of quantitative analysis will be improved by BPANN model trained by more realistic simulation signals in our future work, which can be used for gas recognition and concentration measurement in the actual detection of mixed gases.

Aliphatic polyacetylenes are nutraceuticals. Interactions of the polyacetylenes falcarinol, panaxydol and falcarindiol with human serum albumin (HSA) were studied via steady-state and time-resolved fluorescence, UV–Vis, circular dichroism and Fourier transform infrared (FT-IR) spectroscopies and molecular docking. The value of Stern-Volmer quenching constant (KSV) decreased with temperature increase in fluorescence quenching experiments, and the average fluorescence lifetime (τ) was calculated between 5.25 and 5.40 ns according to time-resolved fluorescence. The results indicated that the quenching mechanism of HSA by the three falcarinol-type polyacetylenes (FTPs) is a static process. FTPs most probably bind HSA at site II alone, located in domain IIIA, as evidenced by competitive ligand displacement and molecular docking studies. The FTPs could induce slight conformational and microenvironmental changes of HSA as determined by three-dimensional fluorescence, circular dichroism and FT-IR measurements, and energy transfer observed. The findings can offer important insights for the further design of potential biologically active FTPs.

Cucumis melo L. var. agrestis Naud. (field muskmelon), a troublesome weed affecting corn, soybean and peanut fields, is difficult to control and drastically reduces crop yields. Farmers have reported that nicosulfuron, imazapic, fomesafen, and bentazon, which are common herbicides used in corn, soybean and peanut fields, do not control field muskmelon effectively. This lack of control might be due to the evolution of resistance to these herbicides in field muskmelon. Thus, this study was designed to determine the sensitivity of field muskmelon to nicosulfuron, imazapic, fomesafen and bentazon. Eleven putative resistant populations and 1 sensitive population were used to evaluate the sensitivity of field muskmelon to these herbicides. Further, we analyzed the cross resistance and multiple resistance in field muskmelon plants. Among the 11 putative resistant populations, 10 populations evolved resistance to nicosulfuron, 6 populations were resistant to imazapic, and 4 populations evolved resistance to fomesafen, whereas none of the populations were resistant to bentazon. Moreover, field muskmelon has evolved resistance to the ALS-inhibiting herbicides nicosulfuron and imazapic, and to the PPO-inhibiting herbicide fomesafen. Fortunately, most of the resistance levels were low. The findings indicate that effective measures are needed to control resistant field muskmelon and avoid the further development of resistance in this plant.

Existing research on shale fracture conductivity is rather sparse and has not taken the effect of loading history into consideration. A splitting device was used to split the shale specimens along bedding, and a 3D scanner was used to characterize the fracture surface. Using a constant 0.3 MPa gas pressure, three shale specimens split by single fractures of different roughness were tested for gas flow during four loading–unloading cycles of 0–10 MPa. Test results show that fracture conductivity exhibited hysteresis similar to that observed in rock mechanics experiments. In addition, it is clear that fracture conductivity is smaller for fractures with rougher surfaces. Building on the cubic law and soil mechanics consolidation theory, a hydraulic aperture model for cyclic loading was developed that helps explain the influence of plastic deformation during loading and unloading on fracture conductivity. This model exhibited trends get the agreement with the data for the range of confining stresses used in the experiments.

Wheat (Triticum spp.) is often coinfected by several soil-borne fungal pathogens, causing serious crop yield and economic losses. Rapid diagnosis of infected fungi is critical for the application of disease control mechanisms. Therefore, we established a multiplex PCR method using specific primers for the simultaneous detection of five common soil-borne fungal pathogens affecting wheat: Rhizoctonia cerealis, Bipolaris sorokiniana, Gaeumannomyces graminis var. tritici, Fusarium pseudograminearum and F. graminearum. The specific primers were designed based on the sequences of several unique genes: ITS (internal transcribed spacer) of R. cerealis, URP-1F (universal rice primer) of B. sorokiniana, β-tubulin of G. graminis var. tritici and TEF1-α (translation elongation factor) of F. pseudograminearum and F. graminearum. During optimization, sensitivity assays showed that the detection limit of multiplex PCR was as low as 0.39 ng of mycelium DNA from a known pool of fungal DNA. To detect pathogens in wheat field, the multiplex PCR method was applied to infected wheat samples collected from wheat fields in the Fengqiu and Taikang counties in Henan Province, China. The R. cerealis and F. graminearum pathogens were identified in samples from Fengqiu, while the R. cerealis, G. graminis var. tritici, B. sorokiniana and F. graminearum pathogens were identified in samples from Taikang. In conclusion, the results indicated that our multiplex PCR method was efficient and specific for the detection of soil-borne pathogens.

Fault damage zones potentially represent native permeable channels within otherwise ultra-tight igneous formations that may be used to promote fluid circulation for convective heat recovery. The United Downs Deep Geothermal Power (UDDGP) project aims to recover geothermal energy by directly injecting, circulating then recovering fluids from such a fault. The UDDGP project injects fluid into the fault at 2500 m where rock temperature is ~75 °C – 80 °C and recovers the injectate from 4500 m, where the bottom hole temperature is predicted to be 190 °C. We explore such down-dip circulation through numerical modeling to determine the anticipated temperature and longevity of the thermal recovery and the potential for induced seismicity (fault reactivation) by contrasting response for up-dip circulation. The results reveal that down-dip circulation not only maximizes water temperature and flow rate at the outlet but also simultaneously suppresses fault reactivation over the long term. In down-dip circulation, fault permeability in the critically stressed shallow fault damage zone is more greatly enhanced than that of the deep fault as a result of the strong injection-induced thermal stress. Fault sealing is breached as a result of reactivation in the shallow fault, prompting transverse fluid penetration and subsequent fluid circulation in the footwall. Switching the injection scheme from down-dip circulation to up-dip circulation, while maintaining an identical injection rate, leads to a drastic increase in the cumulative number of seismic events, with the average magnitude increasing from 1 to 2. This reversed well configuration (circulation bottom to top) also reduces power output from 6 to 7 MWthermal to 2 MWthermal, due to reduced enthalpy and flow rate in the production well. The outcomes from this study confirm the preferred design of the well pattern as circulating top to bottom, to both maximize heat recovery and limit induced seismicity. A lower production pressure is necessary to avoid pressure build-up inside the fault . Production pressure at 15–20 MPa could ensure both high cumulative power generation and a stable fault state.

Typical meteorological years (TMY) serve as basic parameters for building energy consumption simulation and play a key role in building energy-saving design. At present, the most widely used method for generating TMY is the Finkelstein–Schafer statistical method of Sandia Laboratory in the United States. However, when this method is used to generate TMY, all meteorological parameters use a uniform weighting factor which fails to reflect the different regional climate impact differences. It is unreasonable to adopt a unified weighting factor, because the meteorological resources of different climate zones are very different, and the leading role of building energy consumption is different. This paper proposes a new method, applying the entropy-based Technique for Order Preference by Similarity to Ideal Solution(TOPSIS) method for TMY generation. The entropy-based TOPSIS method is an objective method, in which the determination of weight and decision result does not involve any subjective preference but totally relies on the objective data set. This method can reflect the climate differences in different climate zones. The rationality of this method is verified by selecting five typical representative cities in China. The single meteorological parameter deviation analysis and building energy consumption simulation were used to evaluate the generated TMY. The results show that the TMY generated by the entropy-based TOPSIS method is closer to the long-term average. This method only considers monthly data, so the development of entropy-based TOPSIS is simpler and less time-consuming.

Accurate prediction of outdoor air temperature is of great significance to improve the energy efficiency of HVAC system and even the whole building. The aim of this paper is to present the development and evaluation of a new algorithm based on pattern approximate matching for the prediction of outdoor air temperature using acquired historical data of five cities in China (Beijing, Harbin, Shanghai, Guangzhou and Kunming) representing different climatic regions. The optimum parameters of the algorithm for each city has been identified by its historical data. The efficiency of the prediction is validated by comparing predicted and measured outdoor air temperature. Furthermore, statistical metrics such as absolute mean error (AME), root mean square error (RMSE), and accuracy were used to evaluate the performance of the algorithm. These metrics confirm the algorithm proposed in this paper is suitable for all the five Chinese cities. All the work has been contacted using Python programming environment.

Coal is a dual-porosity medium with an internal pore-fracture structure that serves as a channel for the migration of coalbed methane. Understanding the relationship between permeability and pore-fracture structure characteristics is therefore of great significance to accurately predict coalbed methane productivity. In this work, we analyze the pore-fracture structure characteristics of real coal samples and establish a new fractal permeability model of dual-porosity media embedded with natural tortuous fractures. Compared with the traditional dual-porosity medium model with embedded parallel plane fractures, this model not only considers the characteristics of pore tortuosity but also those of fracture tortuosity. The results show that the predicted permeability values obtained from the proposed model are 1–2 orders of magnitude lower than those of the traditional model, which implies that the latter overestimates coal seam permeability. The coal matrix permeability is approximately 13 orders of magnitude lower than the fracture permeability, and the latter mainly controls the overall coal seam permeability. Gas flow analysis of the coal seam is conducted in COMSOL Multiphysics, in which a fracture structure image is transformed to the computational domain. We use the results to discuss the relationships between coal permeability and fracture geometric characteristic parameters. The results show that the porosity ϕf and fractal dimension Dl of the fracture substantially affect coal seam permeability and follow a strong power-law relationship. The numerical simulation results are in good agreement with the theoretical predicted values (the average error is about 11.97%), which verifies the accuracy of the proposed model.

Supercritical carbon dioxide (Sc-CO2) has been used in shale gas exploitation for efficient fracturing and the added benefit of CO2 geo-storage. Many studies have suggested that the water wettability of shale significantly influences the success of shale gas recovery. The aim of this work was to investigate the effect of CO2 treatment on shale water wettability. X-ray diffraction (XRD) analysis, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) were used to analyze the raw and CO2-treated shale samples using peak fitting and grey relational (GR) analyses. The results showed that the CO2-treated shale surface showed weaker hydrophilicity than the raw shale sample. The GR analysis results indicated that Si–OH contributed most to shale water wettability because Si–OH formed hydroxyl bonds with the water molecules on the shale surface, significantly enhancing shale hydrophilicity. The proportion of Si–OH in the shale chemical groups decreased, and fewer hydroxyl bonds were formed after the CO2 treatment, weakening shale hydrophilicity. The content of hydrophilic –OH groups was lower in the CO2-treated shale samples than the raw samples, and increases and decrease were observed in the content of the C–O groups. A decrease in the contents of hydrophilic calcite, dolomite, and clay minerals also contributed to shale hydrophilicity weakening. These results imply that the injection of CO2 into shale reservoirs weakens shale hydrophilicity, improving shale gas recovery because the water blocking effect is minimized. The findings in this research can be used for shale wettability reversal by chemical reagents, which is of great significance for improving gas productivity and CO2 geological storage.

Expanded hexanucleotide GGGGCC repeat in a noncoding region of C9ORF72 is the most common cause of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). However, its molecular pathogenesis remains unclear. In our previous study, the expanded GGGGCC repeats have been shown to be sufficient to cause neurodegeneration. In order to investigate the further role of expanded GGGGCC repeats in the neuron, the normal r(GGGGCC)3 and mutant-type expanded r(GGGGCC)30 expression vectors were transfected into Neuro-2a cells. Cell proliferation, dendrite development, and the proteins’ levels of microtubule-associated protein-2 (MAP2) and cyclin-dependent kinase-5 (CDK5) were used to evaluate the cell toxicity of GGGGCC repeats on Neuro-2a cells. The results were shown that expression of expanded GGGGCC repeats caused neuronal cell toxicity in Neuro-2a cells, enhanced the expression of pMAP2 and pCDK5. Moreover, overexpression of Purα repaired expanded GGGGCC repeat-inducing neuronal toxicity in Neuro-2a cells and reduced the expression of pMAP2 and pCDK5. In all, our findings suggested that the expanded GGGGCC repeats might cause neurodegeneration through destroyed neuron cells. And the GGGGCC repeat-induced neuronal cell toxicity was inhibited by upregulation of Purα. We inferred that Purα inhibits expanded GGGGCC repeat-inducing neurodegeneration, which might reveal a novel mechanism of neurodegenerative diseases ALS and FTD.

The conventional mechanical and permeability models for proppant pack consider proppant as an elastic material, however, loading stresses cause proppant rearrangement and crush, leading irreversible material hardening, structure damage of proppant pack, strong reduction of pore space and damage of fracture conductivity. In this work, a confined compression and conductivity test on proppant pack was conducted. According to the experimental results, a new constitutive model for calculating the loading-path dependent proppant deformation and permeability was developed. In the proposed model, a simple yield equation and a non-associated potential equation were applied to derive the irreversible plastic deformation which is further used to calculate the material hardening parameter and the permeability damage. The model was validated by the experimental data and coupled into a reservoir simulator to investigate the impact of the stress shadow effects caused by the current stimulated fracture on the deformation and permeability of the placed proppant in the previous generated fracture. The modeled results revealed that the current fracturing operation damages the conductivity of the previous generated fracture, which must be taken into account for production prediction.

Interest in shale gas as an energy source is growing worldwide. Because the rock’s natural fracture system can contribute to gas production, it is important to understand the flow behavior of natural fractures in shale. Previous studies on the flow characteristics in shale fractures were limited and did not consider the effect of nonlinearity. To understand the basic mechanics of the gas flow behavior in shale fractures, laboratory investigations with consideration of the fluid pressure gradient, the confining stress, the loading history and the fracture geometry were conducted in this paper. Izbash’s equation was used to analyze the nonlinearity of the flow. The results show that the behavior of the friction factors is similar to that shown in flow tests in smooth and rough pipes. The increase of the confining stress and the irreversible damage to the shale decreased the hydraulic aperture and increased the relative roughness. Thus, turbulent flow could appear at a low Reynolds number, resulting in a significant pressure loss. The limits of the cubic law and the existing correction factor for transmissivity are discussed. It is found that the previous friction models overestimate the friction factor in the laminar regime and underestimate the friction factor in the turbulent regime. For this reason, a new friction model based on a linear combination of the Reynolds number and the relative roughness was developed.

Oxidative stress is considered as one of key factors related to Alzheimer's disease (AD), while kinetin (KT) has been reported to exert anti-oxidative activities as well as neuroprotective effects both in vivo and in vitro. Thus, in this study, the neuroprotective effects of KT against glutamate-induced oxidative toxicity in HT22 cells were investigated. To evaluate the anti-oxidative capabilities of KT itself, several anti-oxidative assays in vitro were conducted. To evaluate the neuroprotective effects of KT, the levels of intracellular reactive oxygen species (ROS) and calcium influx, mitochondrial membrane potential (MMP), and cell death were measured by flow cytometry. Nuclear translocation of apoptosis inducing factor (AIF) and content of intracellular ATP were also determined. In addition, the phosphorylation levels of apoptosis signal-regulating kinase 1 (ASK-1), c-Jun N-terminal kinase (JNK), and p38 mitogen-activated protein kinases (p38) were evaluated as well. Besides, nuclear translocation of nuclear factor-E2-related factor 2 (Nrf2) and the expression of heme oxygenase-1 (HO-1) were also examined to reveal underlying mechanisms. Results showed that KT rescued cell death, and suppressed the accumulation of intracellular ROS and the increase of intracellular calcium influx. In addition, KT maintained normal function of mitochondria and inhibited the phosphorylation of ASK-1, JNK, and p38. KT also promoted nuclear translocation of Nrf2 and enhanced the expression of HO-1 both at protein and mRNA level. Importantly, blockage of Nrf2 almost completely abolished the neuroprotective effects of KT, while blockage of HO-1 expression partly neutralized its neuroprotective effects. Our results indicated that KT can protect HT22 cells from glutamate-induced cell death by activating Nrf2 pathway and inducing expression of HO-1, suggesting KT might be a drug candidate for treatment of AD and other neurodegenerative disorders related to oxidative stress.

Increasing evidence indicates that aluminum exposure and oxidative stress play crucial roles in the initiation and development of Alzheimer's disease (AD). Aluminum chloride (AlCl3) and d-galactose (d-gal) combined treatment of mice is considered as an easy and cheap way to obtain an animal model of AD. Kinetin is a plant cytokinin, which is also reported to exert neuro-protective effects in vivo and in vitro. Thus, in this study, neuro-protective effects of kinetin were investigated in an AD model of mice induced by AlCl3 and d-gal. The Morris water maze (MWM) test was performed to directly evaluate neuro-protective effects of kinetin on the memory and spatial learning abilities, while the histopathological changes were examined by hematoxylin and eosin (H & E) staining method. To further investigate mechanisms involved, Al content in cortex and hippocampus was determined. In addition, related detection kits were used to determine acetylcholine (ACh) content and activity of acetylcholinesterase (AChE). Activities of anti-oxidative enzymes including superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px), and the content of heme oxygenase-1 (HO-1) were also measured. Besides, the content of oxidative damage bio-markers including 8-iso-prostaglandin F (8-iso-PGF), advanced glycation end products (AGEs) and 8-hydroxy-2-deoxyguanosine (8-OHdG) were determined by ELISA kits. Finally, the distribution of beta-amyloid protein 1-42 (Aβ1-42) was detected by immunohistochemistry (IHC), while the expression levels of amyloidogenic proteins including β-amyloid precursor protein (APP), β-secretase, γ-secretase and Aβ1-42 were detected by western blotting (WB) method. Results showed that kinetin improved performance in MWM test, attenuated histopathological changes, reduced Al level in cortex and hippocampus, increased ACh content and decreased AChE activity. In addition, kinetin elevated activities of anti-oxidative enzymes and reduced the levels of oxidative damage biomarkers in AD model of mice. Furthermore, kinetin also increased the content of HO-1, and inhibited the distribution of Aβ1-42 and the expressions of amyloidogenic proteins (APP, β-secretase, γ-secretase and Aβ1-42) in brain tissue of AD mice. Our results indicate that kinetin has neuro-protective effects on the AD model of mice induced by AlCl3 and d-gal, suggesting that kinetin may be a candidate drug for treatment of AD.

Shale gas is the second largest source of unconventional fuel in the world. Supercritical carbon dioxide (SC-CO2) fracturing not only allows effectively breaking paper to the shale gas recovery but also could the replace of methane with carbon dioxide. In this method CO2 adsorption in the shale affects the physical and chemical structure of the shale formations. Therefore, the change of reservoir physical properties will affect the efficiency of fracturing. The main objective of this study is to investigate supercritical CO2 (SC-CO2) effects on the physical structure (porosity, deformation, and mechanical properties) and chemical structure (mineral components) of the shale. Four types of experiments were conducted: (1) pore characteristics by low-pressure nitrogen adsorption. (2) the mineral composition of the shale test. (3) The CO2-induced (adsorption-induced and pressure-induced) deformation of the shale teste. (4) The triaxial compressive strength and tensile strength of samples test. The results show that shale pore properties could be change by the SC-CO2. The specific surface of the shale decreased and the porosity and average pore size increased. The mineral content of the shale minerals (except quartz) decreased after SC-CO2 treatment. The samples exhibited swelling strains caused by SC-CO2. At low pressures, shale deformation was mainly caused by adsorption, while deformation at higher pressures was mainly caused by pressure. After the SC-CO2 treatment, the tensile strength, triaxial compressive strength, and elastic modulus of the shale decreased. The strength decreased as the treatment time increased. The changes in the strength of shale could be explained by two mechanisms: the dissolution effect of SC-CO2 and the adsorption/pressure-induced strain. It indicate that supercritical carbon dioxide can change the characteristics of shale reservoir, and it could reduce the fracturing pressure of supercritical carbon dioxide fracturing and enhance the efficiency of fracturing.

Volatile compounds have a tremendous impact on fruit quality. We evaluated the volatile compound profiles of ripening wild apple fruit (10 Malus baccata accessions and three Malus prunifolia accessions) in the National Field Genebank for Hardy Fruits at Gongzhuling, China. Alcohols, esters, aldehydes, terpenes, hydrocarbons, ethers, heterocycles, carboxylic acids, and ketones were detected in the M. baccata and M. prunifolia fruit, with the first four being the main volatile compounds present. Of the 92 volatiles detected, esters were the most diverse (49 compounds). This wide range of abundant volatile compounds suggests that M. prunifolia is a good resource for breeding apple cultivars with novel and interesting flavors. The M. baccata accession ‘Zhaai Shandingzi’ and the M. prunifolia accession ‘Bai Haitang’ had the widest range of volatile compounds and the highest volatile compound contents of the accessions examined, and will therefore be good breeding materials for developing commercial lines with enhanced flavor and for widening the genetic diversity. The number of different ester compounds present was significantly positively correlated (r = 0.877) with the cube root of the weight of an individual ripe fruit. Principal component analysis (PCA) showed that the contents of ester compounds could be used to distinguish between M. baccata and M. prunifolia species. Therefore, ester compounds could be used as a reference of parental choice in apple breeding.

Astragaloside IV(AS-IV), a saponin purified from Astragalus membranaceus (Fisch.) Bge.var.mongholicus (Bge.) Hsiao, has been widely used in traditional Chinese medicine. However, the underlying mechanisms in treating chronic glomerular nephritis (CGN) have not been fully understood. The aim of the present study was to evaluate the potential mechanism of AS-IV on CGN. CGN rats were administrated with AS-IV at 10 mg·kg-1 ·d-1 (ASL) and 20 mg·kg-1 ·d-1 (ASH). Twenty four hour proteinuria, blood urea nitrogen (BUN), and serum creatinine (SCr) were detected. Hematoxylin-eosin (HE) and periodic acid-Schiff (PAS) staining were performed to evaluate the kidney lesion. Transmission electron microscope and GFP-RFP-LC3 transfection assay were used to monitor the effect of AS-IV on autophagy. IL-6 and IL-1β were detected. The expression of CyclinD1, PI3K/AKT/AS160 pathway and autophagy related proteins were detected by Western Blot. The results demonstrated that AS-IV improved kidney function, ameliorated kidney lesion, and diminished inflammatory in CGN rats. Further, both in vivo and vitro study demonstrated that AS-IV inhibited the proliferation of mesangial cells. AS-IV further displayed a remarkable effect on inhibiting the activation of PI3K/AKT/AS160 pathway and improved the activation of autophagy in vivo and vitro. These results suggested that AS-IV is a potential therapeutic agent for CGN and merits further investigation.