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BACKGROUND Wastewater containing heavy metals produced by mining, beneficiation, smelting, forging, processing, transportation, and other industries that has been improperly disposed of, leads to heavy metals entering and polluting the groundwater environment. Heavy metals can be enriched in the human body and participate in the biological cycle. Long-term accumulation of heavy metals in the human body will bring carcinogenic, teratogenic, and mutagenic risks. Adsorption has been of wide concern in the treatment of heavy metals pollution in water, due to the advantages of low operation cost, simple engineering operation and low secondary pollution. Chitosan as a natural organic polysaccharide organic matter, has the characteristics of being environmentally friendly. It contains many nitrogen-containing functional groups that can adsorb metal ions in water. However, the adaptability of chitosan adsorbents to acidic conditions is poor, so the pH value needs to be adjusted in the actual process, which increases the operating cost. Combining biochar with chitosan can not only improve the adsorption capacity of chitosan, but also improve the separation performance of biochar. However, most of the research on chitosan modified biochar concentrate on the single biochar. There are few studies on the modification of biochar from different sources by chitosan, and the interaction between chitosan and biochar is not clear. OBJECTIVES The aim of this study was to prepare peanut shell biochar-chitosan magnetic composite adsorbent (PSC) and corn cob biochar-chitosan magnetic composite adsorbent (CCC), and to investigate the Pb2+/Cu2+ adsorption properties and mechanisms on PSC and CCC. METHODS Scanning electron microscope was used to analyze the microstructure of the material, and the material samples were treated with gold spray before photographing. The specific surface area and pore volume of the material were determined using a specific surface area analyzer, and the material was adsorption-desorption tested with nitrogen at -196℃. X-ray diffraction was used to analyze the crystal structure of materials, and the Cu Kα source was used to scan in the range of 10°-80° (2θ). X-ray photoelectron spectrometer was used to analyze the changes of functional groups on the surface of the material, and the radiation (225W, 15mA, 15kV) was carried out by monochromatic Al-Kα. Metal ion content in solution was measured by inductively coupled plasma-optical emission spectrometry. The adsorption experiments were carried out in a 50mL conical flask and a constant temperature shaker. The oscillation frequency was 150r/min and the reaction time was 12h. After the reaction, the concentrations of Pb2+ and Cu2+ in the solution were determined. Two parallel samples were set up in each group. Different initial pH experiments were used to evaluate the adsorption performance of materials. Kinetic and isothermic models were used to evaluate the adsorption kinetic process of materials and predict the maximum adsorption capacity of materials. Recycling experiments and actual mine groundwater adsorption experiments were used to evaluate the practical application capacity of materials. RESULTS SEM images of PS and CC showed that there were many pores on the surface of both types of carbon. There were more pores and bulges observed on the surface of CC than PS, indicating that CC had a larger contact area with pollutants than PS. The specific surface area (12.045m2/g) and mean pore diameter (3.614nm) of CC were larger than those of PS (specific surface area was 3.294m2/g and mean pore diameter was 3.067nm), which was consistent with the SEM results. The specific surface area (4.598m2/g) and average pore diameter (3.417nm) was 2.812nm), indicating that the primary structural properties of biochar affected the pore structure of the composites. SEM of CCC and PSC showed that chitosan and biochar were well combined. Compared with previous literature, the biochar-chitosan composite material in this study preserves the original structure of biochar to the greatest extent, and makes the chitosan evenly coated on the surface of biochar. The results BET showed that the primary structural properties of the biochar affected the physical properties of the modified materials. The XRD results showed that Fe3O4 was successfully embedded into the composite material. Three pH values (4, 7 and 10) were selected to evaluate the swelling properties of the materials. The results showed that the swelling ratios of the two materials were similar under the three pH conditions, and neither of them was more than 100.0%, which was due to the biochar as a carrier having a good supporting effect. Compared with chitosan/kiwifruit branch biochar adsorbent, the two adsorbents in this study showed relatively stable adsorption properties in the pH range of 4-7, indicating that the adsorbents had a wider range of pH value application. The effect of the initial pH on the adsorption was tested. As the initial pH value increased from 3 to 7, the adsorption capacity and removal efficiency of the material increased. The positive charge of the adsorbent surface also decreased, which reduced the electrostatic repulsion of Pb2+ and Cu2+ between the material surface and the solution, and increased the electrostatic attraction between the material surface and Pb2+ and Cu2+. The increasing electrostatic attraction was beneficial to the adsorption of Pb2+ and Cu2+. When PSC and CCC adsorbed Pb2+, the pseudo-first-order kinetic model could better describe the adsorption process than the pseudo-second-order kinetic model, indicating that physical adsorption played a dominant role in the adsorption of Pb2+ by PSC and CCC. Pseudo-second-order kinetics can better fit the Cu2+ adsorption by PSC and CCC than pseudo-second-order kinetic model, indicating that chemisorption dominates the adsorption process of Cu2+ by PSC and CCC. The Langmuir isotherm adsorption model can better describe the adsorption process of Pb2+ and Cu2+ than Freundlich isotherm adsorption model, indicating that the adsorption process is monolayer adsorption. The EDTA-2Na was used as the desorption agent of chitosan composite, the removal efficiencies of Pb2+ and Cu2+ were still above 85% after five cycles, which indicated that the two adsorbents in this study had excellent stability. PSC and CCC were the low-cost and effective adsorption materials. Groundwater of an acid mine was taken from a mining area in Dongshan District, Dafan Mountain, Anhui Province. The groundwater samples contained large amounts of metal ions, such as As, Ca, Cd, Cu, Fe, Mn, Na and Ni, the corresponding concentrations were 18.200g/L, 40.541mg/L, 3.800g/L, 13.300mg/L, 215.00mg/L, 510.00g/L, 81.694mg/L and 87.000g/L, respectively. 0.45μm filter membrane was used to remove particulate impurities from the water before adsorption. CCC was used to treat the heavy metal polluted groundwater, and the results showed that CCC has a good removal ability on a variety of metal ions in groundwater such as Cu2+, Cd2+, and Fe3+. The Cu2+ concentration in the treated water can reach the Grade IV water standard of the “Groundwater Quality Standard”. The pH results showed that the removal mechanisms of Pb2+ and Cu2+ by PSC and CCC mainly included electrostatic attraction. The functional groups of adsorbents before and after adsorption were analyzed through X-ray photoelectron spectroscopy (XPS). The results of XPS showed that complexation was another removal mechanism. The nitrogen (—NH) of pyrroles, amino of chitosan (—NH2), and C=N were the main functional groups, which were responsible for the complexation with Pb2+ and Cu2+. CONCLUSIONS The preparation method of the materials in this study can effectively improve the adaptability of chitosan materials under different pH conditions. The adsorbents developed in this study can effectively remove heavy metals from groundwater and have a good application potential.

Optimizing the scanning path of the fiber detection device helps to further reduce the detection time and improve the detection efficiency. Considering that each fiber must be detected and detected only once, which has the basic characteristics of the traveling salesman problem (TSP)，so an anchor box algorithm for fiber coordinate transformation of 4x objective lens coarse scanning and 40x fine scan was proposed. Aimed at the motor motion mode in the scan process, the distance evaluation formula of the TSP mathematical model was modified, the meta-heuristic, heuristic and other algorithms were used to solve the optimal path, three different scales of 800, 1 200, and 1 500 points were selected for scanning path distance and time test. The experiment results show that compared with the traditional Z-type global scan method, the proposed shortest time scan algorithm reduces the total scan path length by 53.0％~67.7% and the total scanning time by 21.0％~41.9%.

At present, there are problems such as the subjective influence of classification results, expensive detection equipment, and long detection time in the common fiber classification technology. In view of these issues, a modified ResNet-50 neural network was proposed, which is based on the pre-training of ImageNet dataset, to classify four animal hair fibers with similar fiber structures. Taking TensorFlow and Keras as the framework, the basic models of ResNet-50 and VGG-16 was used for verification, and then the ResNet-50 network structure and parameters was adjusted by adding Dropout layer and data enhancement strategy. Finally, the adjusted ResNet-50 network was tested with the test datasets, and the confusion matrix was introduced for evaluating each performance index of the network. Compared with original ResNet-50 and VGG-16 networks, the experiment result shows that the adjusted ResNet-50 model has better comprehensive classification performance with an average accuracy of 98.88% and an average F1 score of 98.88%.

In order to explore the effect of chemical modification on the inhibitory effect of intracellular polysaccharides of Phaeodactylum tricornutum (PTP) on the proliferation of cervical cancer Hela cells, in this study, the PTP was extracted by the ultrasound-assisted wall-breaking method combined with the hot water extraction method. Four types of chemical modification (sulfation modification, phosphorylation modification, acetylation modification and carboxymethylation modification ) were carried out on the PTP. The inhibitory effects of the initial PTP, sulfated polysaccharide (S-PTP), phosphorylated polysaccharide (P-PTP), acetylated polysaccharide (A-PTP) and carboxymethylated polysaccharide (C-PTP) on the proliferation of cervical cancer Hela cells were studied. The results showed that the degree of substitution of the S-PTP was 0.714, and the inhibitory effect of S-PTP on the proliferation rate of Hela cells could be up to 9.22% higher than that of PTP. The degree of substitution of P-PTP was 0.191, and the inhibitory effect of P-PTP on the proliferation rate of Hela cells could be up to 4.01% higher than that of PTP. The degree of substitution of acetylated polysaccharide A-PTP was 0.513, and the inhibitory effect of P-PTP on the proliferation rate of Hela cells could be up to 13.53% higher than that of PTP. The degree of substitution of C-PTP was 0.915, and the inhibitory effect of C-PTP on the proliferation rate of Hela cells could be up to 8.39% higher than that of PTP. The results showed that the inhibitory effects of four modified polysaccharides on the proliferation of Hela cells were all greater than that of PTP. Acetylation modification had the greatest inhibitory effect on the proliferation of Hela cells. Compared with PTP, the inhibitory effect of A-PTP against the proliferation rate of cervical cancer Hela cells was increased by 13.53%, reaching 46.05%. Through the experiments of chemical modification of PTP, it was proven that the introduction of a new chemical group into the molecular structure of PTP can lead to a great influence on the inhibition of cervical cancer cell proliferation. This result provides an important reference for further study on the biological activity of Phaeodactylum tricornutum and an experimental basis for subsequent drug research and development. [ABSTRACT FROM AUTHOR]

Mg2Ni-Ni-5%RExOy(CeO2, Nd2O3, Tb4O7) composites were synthesized via ball milling method. The microstructure and hydrogen storage properties of the materials were analyzed systematically by XRD, SEM, EDS, the electrochemical and kinetic measurements. The results show that the crystallinities of the composites with rare earth oxides decrease, and the distribution of the rare earth oxide catalysts on the surface of alloys is uniform. The maximum discharge capacities of the composites with rare earth oxides rise evidently,the discharge capacity of the sample containing Tb4O7 reaches to 871mAh·g-1 at room temperature, and the composites can also keep higher cycling stability. The CeO2 and Tb4O7 catalysts can enhance the abilities of charge transfer on the surface of alloys, and improve the transmission rate of H atoms in the bulk of Mg2Ni alloy obviously. The rare earth oxides catalysts can also increase the gaseous hydrogen absorption capacity. The hydrogen storage capacity of the sample with Tb4O7 reaches to 2.02%(mass fraction) at 250℃, which is the maximum hydrogen absorption capacity among these samples, but the hydriding rate is relatively slow at lower temperature. The catalytic effect of the rare earth oxides is mainly related to the changeable valences of the rare earth ions, that is, the more likely of the valences change of the ions, the better the catalytic activities exhibit. The catalytic activities in descending order are Tb4O7, CeO2 and Nd2O3.

With the continuous development of quantum chemical theories and advances in computer hardware and software, the methods for quantum chemical calculation of nuclear magnetic resonance parameters (qcc-NMR) are improved significantly in the past decade. With these methods, accurate calculated results can often be obtained at a relatively low cost. Furthermore, the methods for result analysis have been advanced from simple statistical parameters to more sophisticated procedures based on more complicated statistical methods or artificial neuron networks, etc. These advances make qcc-NMR a significant complement to traditional spectrometric methods, and more and more useful in natural product research. In this paper, the application of qcc-NMR in natural product research is reviewed. Representative researches featuring the use of qcc-NMR are highlighted.

In order to enhance the automation level of metallographic image analysis and accurately obtain key information reflecting material properties such as grain size, a grain boundary segmentation method based on multi-task learning is proposed. This method designs a relationship prediction auxiliary task to improve the accuracy of grain boundary extraction by focusing on the internal information of grains. Simultaneously, contrastive learning is used to train feature extractors, making the model more targeted towards grain boundary topological structures. A metallographic microstructure recognition system based on relationship prediction task is implemented under the Pyside2 framework. Through experimental verification, this system not only assists laboratory technicians in intelligently detecting microscopic structural information such as grain size but also significantly improves the software's applicability, detection efficiency and accuracy. [ABSTRACT FROM AUTHOR]

In order to solve diverse quality and privacy leakage of perceived data in fog-cloud integrated internet of things (IoT), a streaming encryption-based privacy-preserving truth discovery mechanism for IoT was proposed. Firstly, by utilizing shuffling and streaming encryption algorithms, the ground truths and the weights were anonymously updated on the cloud server and fog server, respectively, so that the collusion attacks between malicious attackers and cloud or fog servers could be resisted to defend against privacy leakage of IoT devices. Secondly, by adopting the Softmax function, the device weights were calculated on fog server, which reduces the error rate for calculating the ground truths. Finally, the theoretical analysis proved that the mechanism could protect privacy of the devices. And, the experimental results demonstrate that the proposed mechanism is an effective privacy-preserving trust discovery mechanism for large-scale IoT devices, which can outperform existing ones in computing efficiency. [ABSTRACT FROM AUTHOR]

In order to mitigate the fine migration in coalbed methane wells after fracturing operation, both of the origin and damage of fines were analyzed. Taking the coalbed methane wells located in southern Shizhuang Block of Qinshui Basin as an example, based on proximate analysis and X-Ray results, the wettability of coal fines were concluded with DLVO theory. It was demonstrated that water wetting of coal fines could explain why the flow rate of water accelerated the migration of coal fines. During the flow back period and the dewatering period, the coal fines were much easier to release. The results also indicated that the blockage of coal fines in near wellbore area would do more harm to the productivity of gas wells, because the effective stress and water flow rate in the near wellbore area were higher than other areas. Measures to relieve the injuries of fines were also proposed, including indirect fracturing to avoid the soft coal, applying cationic surfactant instead of anionic surfactant in fracturing fluid, and slower dewatering rate. [ABSTRACT FROM AUTHOR]

Base on an 8-year field experiment, the effects of tillage practices coupled with or without straw return on the soil organic carbon (SOC) and water use efficiency (WUE) were investigated in Guanzhong Plain during the growing seasons from 2008 to 2009. The results showed that con- servation tillage practices (sub-soiling, SS; rotary tillage, RT; no-till, NT) improved the SOC, WUE and crop yield compared with conventional tillage (CT), among which, SS coupled with straw return had the highest increment, with increase in SOC content of the 0-30 cm soil layer, WUE and crop yield by 19. 5%, 16. 9% and 20. 5%, respectively. The NT practice effectively increased the SOC content of the 0-10 cm soil layer. Conclusively, under the current soil and climatic conditions in Guanzhong Plain, sub-soiling coupled with straw return is the most efficient tillage practice for promoting SOC accumulation, increasing water-use efficiency and yield. [ABSTRACT FROM AUTHOR]

This paper proposed a novel architecture for WSN based on cloud computing. The whole WSN divided into several zones. A cloud acted as a virtual sink and had many sink points, each of which collected sensing data from sensors in a zone. The sensors of a zone constituted local wireless sensor networks (LWSNs). All LWSNs integrated together through the cloud. The cloud stored collected sensing data in distributed manner and processed them in parallel way. Simulation results show that the data transmission performance of sensors in the proposed architecture improved significantly. The proposed architecture is suitable for data centric wireless sensor network. [ABSTRACT FROM AUTHOR]

Computation method for effective path of SAR double bounce scattering from trees based on undulating terrain is presented. The large-scale elements of surface fitting are used to describe the variation of surface slope. Through conditional searching of scattering particles and double bounce scattering, the situation that there may be none or many effective paths of double bounce scattering from trees when the terrain is undulating with large-scale feature is fully considered. In order to improve the computation efficiency, the searching area is restricted and the forest stand is divided into three-dimension grids. The conditional searching for the seattering particles in a certain grid is based on the effective path searching results at the center of the grid. Example simulation of double bounce scattering effective path has been demonstrated based on fractal DEM and measured DEM. Results indicate that, compared with the result based on tilted ground with single slope, the proposed method could effectively characterize the double bounce scattering from trees based on undulating terrain. [ABSTRACT FROM AUTHOR]

There are many problems in coalbed methane cementing resulted from the characteristics of coalbed formation, such as low pressure, low permeability and weak cementation. Aimed to solve these problems, evaluation experiments of light weight additive, baseline formula of cement system, low temperature early strength stabilizer, fluid loss additive and dispersing agent were performed. On this basis, the ultra low density cement slurry was developed. Besides, bridging type preflush was researched. The ultra low density cement slurry and bridging type preflush formed the ultra low density cementing technology for coalbed methane. There is no capillary channel in the surface of preferred hollow glass microsphere, so it has good resistance to pressure and shear. The ultra low density cement slurry has many good performances, such as no free liquid, slurry stability, small API filtration loss (≤ 45 mL/30 min), adjustable thickening time and early strength at low temperature. Moreover, the bridging type preflush has good filtration control property (≤19 mL/30 min),effective shut off capacity to the fractures and pores in the No. 3 coalbed core, and good compatibility with ultra low density cement slurry. This ultra low density cementing technology has been applied in two wells for field trial successfully at Qinnan demonstration plot, and the service density is respectively 1.15 g/cm³ and 1.20 g/cm³. Acceptability of cement job quality is 100%,and high quality is above 96%. [ABSTRACT FROM AUTHOR]

In view of the collapsibility of borehole face and coal formation pollution resulted from drilling fluid, developed the light weight drilling fluid through optimization experiments of hollow glass microspheres light weight additive and evaluation experiments of its influence on drilling fluid performances. The density of the developed light weight drilling fluid was reduced by adding hollow glass microspheres. The evaluation experiments of drilling fluid performances show that the light weight drilling fluid has good rheological property and filtration property, and its mud cake is thin and tight, its API filtration loss is less than 5 mL, and is less than 15 mL at high temperature and pressure, and after aging 16 h at 120 °C, the drilling fluid performance is stable, which shows that it has good temperature tolerance. Moreover, this drilling fluid has a lot of good properties, such as antipollution, anti-sloughing, blocking, sedimentation stability and formation protection. This light weight drilling fluid, whose density is 0.95 g/cm³, was applied in one well for field trial successfully at Qinnan demonstration plot. Good performance on protecting coal formation from pollution, which is good for sequent development of coalbed methane, was observed. [ABSTRACT FROM AUTHOR]

PURPOSE: To evaluate the function of cbfα1 on BMP-2 signaling to extracellular matrix proteins in dental papilla cells in vitro. METHODS: RT-PCR and Western blot were performed to detect the expression of ALP, OC, ON, OPN, BSP, DMP-1 and DSPP in cultured dental papilla cells induced by 200ng/mL BMP-2 and/or down-regulated by cbfα1 antisense technology, the results were analysed with SPSS 11.0 software package. RESULTS: We found that the amount of ALP and OC and the expression of OPN, BSP and ON were upregulated significantly after the cells were treated with BMP-2. After transfected with antisense cbfα1, the cells downreguleted the expression of ALP, OC, OPN and BSP significantly(P<0.01). CONCLUSIONS: As a kind of transcription factor, cbfα1 could be an important tache in the BMP-2 signal networks controlling cells differentiation and mineralization. [ABSTRACT FROM AUTHOR]

At present, the breakthrough of the key techniques of artificial intelligence (AI), including image recognition, deep learning, neural network, Robot technique, etc., greatly promote the development of discipline crossing and medicine. In the present paper, we make an in-depth discussion about the future application of inter-discipline techniques of acupuncture-moxibustion and AI. We think that some of the current instruments have been part of the new acupuncture-moxibustion devices and may have the potential to intersect with the AI discipline. Relying on these existing devices and those of meridian detection, we can obtain relatively objective data, and further conduct meridian-syndrome differentiation and big data collection to possibly realize remote medical treatment. In addition, we may also develop an AI system for studying the underlying mechanisms of acupuncture and moxibustion therapies. Nevertheless, there still exist a lot of problems and challenges in clinical, teaching and scientific researches. It is recommended that the discipline of acupuncture-moxibustion should be intersected with the AI subject and formulate appropriate development strategies, promoting a faster and better development of acupuncturology.

Objective: To observe the effectiveness of digital subtraction angiography (DSA) assisted musculoskeletal flap transplantation in the treatment of osteonecrosis of the femoral head (ONFH)., Methods: The clinical data of 15 patients with 15 hips of ONFH admitted between January 2016 and December 2019 were retrospectively analyzed. All patients were male, aged 20-45 years, with an average age of 31.6 years. There were hormone type in 9 cases and alcohol type in 6 cases. The disease duration ranged from 15 days to 3 years, with an average of 8 months. The Association Research Circulation Osseous (ARCO) staging: 4 hips in stage Ⅱ, 11 hips in stage Ⅲ. The preoperative visual analogue scale (VAS) score was 6.2±0.2, and the Harris score of the hip joint was 57.3±1.3. Preoperative DSA examination of the femoral head was performed to determine the location of vascular lesions of the femoral head. According to the results of the angiography, the surgical selection of the musculoskeletal flap was guided. For the patients with both superior and inferior retinaculum vessels developed, simple core decompression was performed. For the patients with superior retinaculum vessels developed but inferior retinaculum vessels not developed, anterolateral tensor fasciae flap was used. For the patients whose superior retinaculum did not develop and the inferior retinaculum developed, posterolateral quadratus femoris flap was used. The fibular flap with anastomotic vessels was used in the patients whose superior and inferior retinaculum vessels were not developed., Results: All 15 cases of 15 hips were followed up 6-24 months, with an average of 14 months. During the follow-up, the patient's ONFH did not worsen, the femoral head did not collapse, the joint space was normal, and the hip joint fextion and extension function was acceptable. At last follow-up, the VAS score was 1.9±0.2, and the hip Harris score was 92.1±0.8, both of which were significantly improved when compared with preoperative ones ( t =14.85, P =0.00; t =23.22, P =0.00)., Conclusion: For patients with ONFH who need musculoskeletal flap transplantation, preoperative DSA of femoral head can determine the location of vascular lesions of femoral head, so as to guide the selection of musculoskeletal flap transplantation, which is of great significance for hip-conserving surgery.

Objective: To observe clinical effect of acupuncture combined with conventional visual stimulation on cerebral visual impairment (CVI) in children aged 3-10 years and influence on the pattern visual evoked potential (P-VEP)., Methods: A total of 60 cases of children aged 3-10 years with CVI were randomly divided into an observation group and a control group, 30 cases in each group. The children in the control group received conventional visual stimulation therapy, 1 month as a course of treatment. On the basis of the control group, the children in the observation group was treated with acupuncture at Baihui (GV 20), Jingming (BL 1), Taiyang (EX-HN 5), Sibai (ST 2), etc. 3 times a week, and the treatment was given 4 weeks continuously as a course. Both groups received 3 courses of treatment. The visual acuity and P-VEP improvement were compared between the two groups before and after treatment., Results: After treatment, the incubation period (P100-L) of the two groups was shorter than before treatment, and the amplitude (P100-A) was higher than before treatment ( P <0.05); and the degree of above changes in the observation group was lager than the control group ( P <0.05). The percentage of best corrected visual acuity of 0.6-0.8 in the observation group after treatment and follow-up 1 year after treatment was higher than before treatment ( P <0.05), and was higher than the control group ( P <0.05)., Conclusion: Acupuncture combined with conventional visual stimulation can improve the incubation period (P100-L) and amplitude (P100-A) of P-VEP in children with CVI, and improve the best corrected visual acuity in children, the clinical effect is better than the conventional visual stimulation alone.

Objective To investigate the correlation between serum total 25-hydroxyvitamin D[T-25(OH)D]level and fecal microbiota in patients with inflammatory bowel disease(IBD). Methods Twenty-three patients with IBD completed the tests for serum T-25(OH)D,and the fecal microbiota was studied using V4 hypervariable region of 16S ribosomal RNA(rRNA)gene sequencing.According to serum T-25(OH)D level,the patients were divided into three groups including vitamin D normal group( n =5),vitamin D insufficiency group( n =5),and vitamin D deficiency group( n =13). Results There was no significant difference between these three groups in Alpha diversity or Beta diversity.Ternary pot at phylum level revealed that the abundance of Proteobacteria was the highest in the vitamin D deficiency group and Actinomycete was the highest in the vitamin D sufficiency group.Spearman correlation analysis showed that at the phylum level serum T-25(OH)D level was negatively correlated with the abundance of Proteobacteria ( r =-0.445, P =0.033)and positively correlated with the abundance of Actinomycetes ( r =0.447, P =0.033);at family level it was positively correlated with the abundance of Lachnospiraceae ( r =0.414, P =0.049), Bifidobacteriaceae ( r =0.468, P =0.024), Erysipelotrichacea ( r =0.584, P =0.003),and Eggerthellaceae ( r =0.507, P =0.014)and negatively correlated with the abundance of Aerococcaceae ( r =-0.514, P =0.012);and at genus level it was positively correlated with the abundance of Blautia ( r =0.459, P =0.028), Bifidobacterium ( r =0.468, P =0.024),unidentified Erysipelotrichacea ( r =0.485, P =0.019), Faecalitalea ( r =0.544, P =0.007), Anaerostipes ( r =0.475, P =0.022), Romboutsia ( r =0.510, P =0.013), Flavonifractor ( r =0.455, P =0.029),and Erysipelatoclostridium ( r =0.617, P =0.002). Conclusions The fecal microbiota composition varies in IBD patients with different serum T-25(OH)D levels.The abundance of Proteobacteria increases and the abundance of Actinomyces decreases in IBD patients with vitamin D deficiency compared with IBD patients with normal vitamin D level.Serum T-25(OH)D level is negatively correlated with the abundance of some harmful bacteria(e.g. Proteobacteria )but is positively correlated with the abundance of some probiotics such as Lachnospiraceae , Bifidobacteriaceae ,and Anaerostipes .

Objective: To study the effects of Ligustrazine on the Ca 2+ sensitivity in carotid artery smooth muscle of simulated weightless-ness rats., Methods: Twenty-one female SD rats were divided into control group (CON), simulated weightlessness group (TS), simulated weightlessness plus Ligustrazine administration group (LTZ) ( n =7). After 4 weeks, the contractile property and the Ca 2+ sensitivity in carotid artery were measured. Furthermore, the effects of ML-7(a myosin light chain kinase specific inhibitor) on above mentioned parameters were recorded., Results: Compared with CON group, the contractile force induced by phenylephrine (PHE) in TS group was increased by 25.14% ( P <0.01). The force in LTZ group decreased by 13.46% ( P <0.01) and increased by 8.30% compared with TS and CON group, respec-tively. After the artery rings were incubated with ML-7, the force in CON, TS and LTZ group were reduced by 8.84%, 16.24% ( P <0.01) and 3.40%, respectively. Compared with CON group, the contractile force induced by KCl in TS group was increased by 40.46% ( P <0.01). The force in LTZ group decreased by 18.80% and increased by 14.05% compared with TS and CON group, respectively. The force in CON, TS and LTZ group were reduced by 21.97% ( P <0.05), 21.88% ( P <0.01) and 10.84% by ML-7, respectively. Compared with CON group, the pD2[Ca 2+ ] in TS group was increased by 10.03% ( P <0.01). The pD2[Ca 2+ ] in LTZ group was decreased by 7.01% ( P <0.01) and increased by 2.32% compared with TS and CON group, respectively. The pD2[Ca 2+ ] in CON, TS and LTZ group was reduced by 2.42%, 7.43% ( P <0.01) and 2.51% by ML-7, respectively., Conclusions: The contraction of carotid artery is strength-ened in simulated weightlessness rats, it maybe results from the Ca 2+ sensitivity of contractile proteins in smooth muscle increasing. Ligus-trazine can improve the contraction of carotid artery, reducing the Ca 2+ sensitivity and inhibiting myosin light chain kinase may be involved in its mechanisms.

Applications of network pharmacology are increasingly widespread and methods abound in the field of drug development and pharmacological research. In this study, we choose rosiglitazone compound as the object to predict the targets and to discuss the mechanism based on three kinds of prediction methods of network pharmacology. Comparison of the prediction result has identified that the three kinds of prediction methods had their own characteristics: targets and pathways predicted were not in accordance with each other. However, the calcium signaling pathway could be predicted in the three kinds of methods, which associated with diabetes and cognitive impairment caused by diabetes by bioinformatics analysis. The above conclusion indicates that the calcium signaling pathway is important in signal pathway regulation of rosiglitazone compound, which provides a clue to further explain the mechanism of the compound and also provides a reference for the selection and application of methods of network pharmacology in the actual research.

Purpose: To observe the expression of MMP-2 in the periodontal tissues of molars in Beagle dogs after different times of intrusion by mini-screw with cyclic intrusive force., Methods: Three mature Beagle dogs were used for the experiment. On the buccal and palatal sites of the left maxillary second and third premolars, a minis-crew was placed at the inter-radicular septa separately, intruding the tooth with 150 g initial force, which would be reinforced every 4 weeks. The teeth of left side as the experimental group were divided into 3 subgroups, as being intruded 12, 24 and 36 weeks, and the right side as blank control. Then the dogs were sacrificed, and the second and the third premolars with the surrounding periodontal tissue were cut down, fixed, decalcified, wrapped and cut into slices. Immunohistochemical staining with MMP-2 was performed. The average optical density (OD) of MMP-2 was calculated with IPP software, which represented the expression of MMP-2. SPSS 17.0 software package was used for statistical analysis., Results: Immunohistochemical staining revealed that the expression of MMP-2 in control group was low. After tooth intrusion, MMP-2 expression significantly increased in the periodontal tissues of molars, and reached the maximum in the group of 24 weeks. Then MMP-2 expression decreased in the 36-week group but still significantly higher than the control group. There was no significant difference among the 3 subgroups for different intrusion times(P>0.05)., Conclusions: MMP-2 participates in remodeling of the periodontal tissue during tooth intrusion. The expression of MMP-2 is not significantly increased with the extension of the intrusion time with cyclic intrusive force, which suggests that with the use of mini-screw to intrude the molars with cyclic intrusive force, the periodontal tissues of the intruded tooth maintain dynamic balance of bone remodeling.

Base on an 8-year field experiment, the effects of tillage practices coupled with or without straw return on the soil organic carbon (SOC) and water use efficiency (WUE) were investigated in Guanzhong Plain during the growing seasons from 2008 to 2009. The results showed that conservation tillage practices (sub-soiling, SS; rotary tillage, RT; no-till, NT) improved the SOC, WUE and crop yield compared with conventional tillage (CT), among which, SS coupled with straw return had the highest increment, with increase in SOC content of the 0-30 cm soil layer, WUE and crop yield by 19.5%, 16.9% and 20.5%, respectively. The NT practice effectively increased the SOC content of the 0-10 cm soil layer. Conclusively, under the current soil and climatic conditions in Guanzhong Plain, sub-soiling coupled with straw return is the most efficient tillage practice for promoting SOC accumulation, increasing water-use efficiency and yield.

Objective: To evaluate the performance of computer-assisted imaging system in the detection of cervical squamous intraepithelial lesion and quality-assurance., Methods: Manual PAP screening (n = 140 580) and image-assisted screening (n = 32 885) were compared for the detection rates of squamous cell abnormalities, the atypical squamous cells (ASC) to squamous intraepithelial lesion (SIL) ratio, the positive rates of high risk human papillomavirus (HR-HPV) test in the case of atypical squamous cells of undetermined significance (ASC-US), and the correlation between cytopathology and histopathology., Results: Compared with manual screening, computer-assisted imaging system showed increased overall positive detection by 0.32%, decreased detection of ASC by 0.21%, increased detection of low-grade squamous intraepithelial lesion (LSIL) by 0.22%, increased detection of high-grade squamous intraepithelial lesion or worse (HSIL) by 0.31%, and decreased ASC to SIL ratio from 2.59 to 1.60. Computer-assisted imaging system did not change the HR-HPV positive rate of the patients who were ASC-US, or the coincidence rate between cytopathology and histopathology. Moreover, the productivity of the laboratory operation increased 58.33%., Conclusion: Computer-assisted imaging system significantly increases the overall positive detection rate of cervical SIL, improves accuracy and work efficiency of screening, decreases the ASC/SIL rate, and strengths the quality-assurance of laboratory testing.

Myelodysplastic syndromes (MDS) are heterogeneous clonal hematopoietic stem cell disorders with different mechanisms and diverse prognosis. The excess of ring sideroblasts (RS) is an important presentation MDS, but the mechanisms of RS appearance are obscure and the treatment of MDS-RS is intractable. Splicing factors play a very important role in the maturation process of eucaryon mRNA, recent studies indicate that there is a significant causal relationship between splicing factor 3B subunit 1 (SF3B1) mutation and the presence of ring sideroblasts. Lucubrating the downstream molecular of the mutated SF3B1 can facilitate exploring the mechanisms and new therapeutic strategies of MDS-RS.

Today, the understanding of the sequence and structure of biologically relevant targets is growing rapidly and researchers from many disciplines, physics and computational science in particular, are making significant contributions to modern biology and drug discovery. However, it remains challenging to rationally design small molecular ligands with desired biological characteristics based on the structural information of the drug targets, which demands more accurate calculation of ligand binding free-energy. With the rapid advances in computer power and extensive efforts in algorithm development, physics-based computational chemistry approaches have played more important roles in structure-based drug design. Here we reviewed the newly developed computational chemistry methods in structure-based drug design as well as the elegant applications, including binding-site druggability assessment, large scale virtual screening of chemical database, and lead compound optimization. Importantly, here we address the current bottlenecks and propose practical solutions.

A rapid method was developed for discrimination of the geographical origins of rice with pattern recognition technique by near infrared spectrocopy (NIRS). A total of 119 geography signs product Xiangshui rice samples and 90 rice (Non-Xiangshui rice) samples produced from other places were analyzed by NIRS. After first derivative and smooth processing, principal component analysis (PCA) was used to reduce the dimensionality of the spectral data. Through the loading graph of the first three principal components, characteristic wave band (7 700-6 700, 5 700-4 300 cm(-1)) with max-relativity was determined. In whole wave, using agglomerative hierarchical cluster analysis and Fisher's linear discriminant, the discrimination of Xiangshui rice and Non-Xiangshui rice was all 100%. The correct rate of specific geographical origins of Non-Xiangshui rice was 91.9% by cluster analysis and 96.7% by discriminant analysis. For analysis in the characteristic wave bands, the correct rate of discriminant by cluster analysis was higher than the analysis result through the range of the whole band. Therefore, characteristic wave band has strong representativeness. The results indicate that it is feasible to discriminate the geographical origins of rice with pattern recognition technique by NIRS, and selecting characteristic wave band is one of the validated methods to improve the precision of the discrimination mode.

The exponentially modified Gaussian (EMG) model-based genetic algorithm was used as a fitness function for fitting fluorescence spectrogram. The method was effective for solving the interference of fluorescent substance in the course of the multi-component quantitative analysis. As an example, the interference of endogenous fluorophores in different urines with the fluorescence of gatifloxacin (GFLX) was examined. A good eradicating efficacy was achieved by using the fitting fluorescence spectrogram. Under the optimized experimental conditions, the good linear relationship between the fluorescence intensity and GFLX concentration was obtained in the range of 0.06-3.5 microg x mL(-1) with a correlation coefficient of 0.9994. The detection limit and recovery were 0.02 microg x mL(-1) and 99.2%-109.4%, respectively, with the relative standard deviation from 1.3% to 2.7%. The proposed fitting fluorescence spectrometric method was rapid, simple and highly sensitive for the determination of GFLX in different human urine without preseparation. The recovery, selectivity, linearity, precision and accuracy of the method are convenient for routine assays and pharmacokinetic studies.

Objective: To investigate the effect of Gli1 gene silencing by RNA interference (RNAi) on proliferation of K562 cells and its mechanisms., Methods: The small interference RNA (siRNA) was synthesized in vitro. K562 cells were transfected with Gli1 siRNA by the way of lipofection (lipofectamine 2000). Non-specific siRNA transfected cells were used as control. Transfection efficiencies of different siRNA concentrations were detected by flow cytometry and the best siRNA concentration was selected. The silencing effect of siRNA was demonstrated by real time PCR and Westem blot analysis. Cell proliferation was measured by MTT method, cell cycle by PI assay, c-myc and p21 mRNA level was detected by real time PCR analysis., Results: Transfection efficiency of siRNA was increased in a dose-dependent manner when siRNA concentration was below 200 pmol, and the highest transfection efficiency reached (80.11 ± 5.63)%. Both the mRNA and protein level of Gli1 was down-regulated in Gli1 specific siRNA group, the mRNA level was (52.60 ± 3.57)% of that of control group after 24 h (t = 20.33, P < 0.01) and the protein level was (79.31 ± 5.58)% of that of control group after 48 h (t = 6.54, P < 0.01). The cell proliferation rate in Gli1 siRNA group was (94.41 ± 3.58)% (t = 2.40, P = 0.05) and (90.22 ± 3.34)% (t = 4.37, P < 0.01) of that of control group after 24 h and 48 h, respectively. G(2)/M cell cycle arrest was observed, the mRNA level of c-myc was down-regulated while p21 was up-regulated in Gli1 siRNA group after 24 h and 48 h (P < 0.05)., Conclusions: Targeted silencing of Gli1 gene by RNAi inhibits the proliferation of K562 cells, which acts through the down-regulation of c-myc and up-regulation of p21 expression.

The aim of this study was to investigate the biological effect of longikaurin A on multiple myeloma H929 cells. Effects of oridonin and longikaurin A on proliferation of H929 cells were evaluated by CCK-8 assay. Cell morphological features of H929 cells were examined under inverted phase contrast microscope. Apoptosis was determined by Annexin V/PI staining. Expression of caspase-3, caspase-9, and PARP were detected by Western blot. Reactive oxygen species (ROS) level was determined by DCFDA assay. The results showed that longikaurin A (IC(50) 0.85 µmol/L) was more effective than oridonin ((IC(50) 10.66 µmol/L) to inhibit the proliferation of H929 cells. Treatment with longikaurin 2 µmol/L significantly increased the percentage of Annexin V positive cells. Caspase-3 and caspase-9 were activated and PARP, one substrate of caspase-3, was cleaved into 85 kDa fragments. The ROS scavenger N-acetyl-cysteine significantly blocked apoptosis induced by longikaurin A. However, longikaurin A did not increase the ROS level in H929 cells. It is concluded that longikaurin A is more effective than oridonin to induce apoptosis in multiple myeloma H929 cells without increasing the ROS level.