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Additional file 9: Table S3. Univariate and multivariate analyses of the association of predictors with advanced adenoma (I+II cohort).

Additional file 11: Table S5. Univariate and multivariate analyses of the association of predictors with advanced CRC (I+II cohort).

In recent years, with the completion of the new library of Qinghai University, the collection of books in the library has greatly increased. The library has a total collection of 880,000 volumes, covering a dozen disciplines such as science, engineering, agriculture, literature, history, economics, philosophy, law, education, management and medicine. It is difficult for users to find the books they are interested in among the numerous materials. Based on the actual situation of the library of Qinghai University, the differences of different professional users and their personal interests, this paper chooses the item-based collaborative filtering algorithm to realize personalized recommendation. First of all, in the calculation of book similarity, the traditional user score data is not chosen to calculate the similarity, but to calculate the similarity between books and books according to the feature vector of book name. Secondly, in order to avoid the problem of cold start, the system recommends the users who have no borrowing record, but the most borrowed books in their department. The combination of the two realized the personalized recommendation of books. By comparing with other traditional recommendation algorithms, it is found that the algorithm adopted in this paper has better recommendation effect.

Under the circumstance of high reliability demand in satellite onboard switches, an Iterative Round-Robin with SLIP (iSLIP) matching scheduling algorithm with load balancing suitable for Combined Input and Output Queuing (CIOQ) switch is presented in this paper. The implementation of load balancer improves the system reliability and the ability of recovery from failure. The iSLIP algorithm with the function of load balancing is used in a 16 \(\times \) 16 CIOQ switch, and the whole switch fabric is implemented in a Xilinx xc7vx690t FPGA. Typical simulated results are given and analysized.

Based on first-principle calculations, we have systematically explored the nature of the elastic stability and the delta-delta'-epsilon phase transitions in pure Pu at high temperature. It is found that, both the electronphonon coupling and the spin fluctuation effects tend to decrease the tetragonal elastic constant (C') of delta-Pu, accounting for its anomalous softening at high temperature. The lattice thermal expansion together with the electron-phonon coupling can stiffen C' of epsilon-Pu, promoting its mechanical stability at high temperature. The delta-epsilon transition is calculated to take place around 750-800 K, and is dominated by the phonon vibration. The delta' intermediate phase is realized around 750 K mainly because of the thermal spin fluctuation.

The effects of major alloy element contents of Zn, Mg, Cu in Al-Zn-Mg-Cu alloys on the formation and evolution of intermetallic phases during casting, homogenization and solution treatment have been investigated through using X-ray diffraction, scanning electron microscopy and differential scanning calorimetry. Experimental results showed that a relatively higher Zn content with lower Mg and Cu contents was beneficial to the formation of MgZn 2 phase instead of the Al 2 CuMg phase, which resulted in the unicity of the intermetallics in the Al matrix, and that the MgZn 2 phase was easier for diffusion and dissolution during homogenization and solution than the Al 2 CuMg phase. Additionally, the results of the first-principles calculations gave support for explaining the experimental phenomena. A larger absolute value of formation enthalpy and a smaller value of binding energy of the MgZn 2 phase, as compared with the Al 2 CuMg phase, give it priority to precipitate during casting and make it easier to re-dissolve during homogenization and solution treatment. What's more, higher elastic constants with severe anisotropy of Young's modulus make undissolved blocks of Al 2 CuMg phase act as crack initiation, which degrade the performance of the materials.

The 1-(2-naphthlmethyl) isatin-5-formamide compounds can inhibit SARS-3CL proteinase by binding to its substrate pocket, while the N-terminal octapeptide of SARS-3CL proteinase was found to act as a dimerization inhibitor. In this work, the dual functional inhibitors which can occupy both substrate pocket of SARS-3CL proteinase and its dimer interface were designed. Six title compounds were gotten by linking 1-(2-naphthlmethyl) isatin-5-formic acid and N-terminal octapeptides using a polyglycine linker through solid-phase peptide synthesis method. The in vitro inhibition activity against SARS-3CL proteinase was measured by continuous colorimetric assay using colorimetric substrate. Compound 3 showed the highest inhibition activity with an IC50 (half maximal inhibitory concentration of a substance) of 3.8 μmolL - 1 . The change of inhibition activity with the linker length was studied. Inhibitors with the even spacers were showed better activity than the odd ones, which could be explained by the angle restriction of peptide bonds. The modulating of the aggregation state and enzyme activity towards SARS-3CL proteinase were (Article)

The essential oil from the leaves of Macleaya cordata R.Br. obtained by hydrodistillation was analysed by gas chromatography/mass spectrometry. Sixty-eight compounds consisting of up to 92.53% of the essential oil were identified. Antioxidant activities of the essential oil were evaluated by using DPPH radical scavenging and β-carotene–linoleic acid assays. The essential oil showed moderate antioxidant activity. In addition, the essential oil exhibited potential antimicrobial activity against all tested microorganisms, with diameters of inhibition zones ranging from 8.7 ± 0.5 to 17.2 ± 1.2 mm and minimum inhibitory concentration values from 125 to 500 μg/mL. We selected the most sensitive bacterium Staphylococcus aureus as model to observe of the action of essential oils of M. cordata on the membrane structure by scanning electron microscopy. The treated cell membranes were damaged severely. The results presented here indicate that the essential oil of M. cordata may be potential sources of antioxidant and antimicrobial agents in the future.

We report high-precision measurements of the Nusselt number $Nu$ as a function of the Rayleigh number $Ra$ in water-filled rectangular Rayleigh-B��nard convection cells. The horizontal length $L$ and width $W$ of the cells are 50.0 cm and 15.0 cm, respectively, and the heights $H=49.9$, 25.0, 12.5, 6.9, 3.5, and 2.4 cm, corresponding to the aspect ratios $(��_x\equiv L/H,��_y\equiv W/H)=(1,0.3)$, $(2,0.6)$, $(4,1.2)$, $(7.3,2.2)$, $(14.3,4.3)$, and $(20.8,6.3)$. The measurements were carried out over the Rayleigh number range $6\times10^5\lesssim Ra\lesssim10^{11}$ and the Prandtl number range $5.2\lesssim Pr\lesssim7$. Our results show that for rectangular geometry turbulent heat transport is independent of the cells' aspect ratios and hence is insensitive to the nature and structures of the large-scale mean flows of the system. This is slightly different from the observations in cylindrical cells where $Nu$ is found to be in general a decreasing function of $��$, at least for $��=1$ and larger. Such a difference is probably a manifestation of the finite plate conductivity effect. Corrections for the influence of the finite conductivity of the top and bottom plates are made to obtain the estimates of $Nu_{\infty}$ for plates with perfect conductivity. The local scaling exponents $��_l$ of $Nu_{\infty}\sim Ra^{��_l}$ are calculated and found to increase from 0.243 at $Ra\simeq9\times10^5$ to 0.327 at $Ra\simeq4\times10^{10}$., 15 pages, 7 figures, Accepted by Journal of Fluid Mechanics

Ni-Mn-Ga and In-Tl are two examples of shape memory alloys. Their shape memory effect is controlled by the martensitic transformation from the high temperature cubic phase to the low temperature tetragonal phase. Experimentally, it was found that the martensitic transformation, related to the elastic properties, is highly composition-dependent.In order to better understand the phase transition and facilitate the design of new materials with improved shape memory properties, the atomic scale description of the thermophysical properties of these alloys is needed. Therefore, in the presen tthesis, the elastic properties and phase stability of Ni-Mn-Ga and In-Tl shape memory alloys are investigated by the use of first-principles exact muffin-tin orbitals method in combination with the coherent-potential approximation. We present a theoretical description of the equilibrium properties of pure In and standard stoichiometric Ni2MnGa alloy with both cubic and tetragonal structures. In In-Tl alloys, all the calculated composition-dependent thermophysical properties: lattice parameter c/a, tetragonal shear modulus C" = (C11 - C12)/2, energy difference between the austenitic and martensitic phases, as well as electronic structures are shown to be in line with the experimentally observed lowering of the martensitic transition temperature TM with the addition of Tl. For most of the off-stoichiometric Ni2MnGa, the excess atoms of the rich component prefer to occupy the sublattice of the deficient one, except for the Ga-rich alloys, where the excess Ga atoms have strong tendency to take the Mn sublattice irrespective of the Mn occupation. In Ni-Mn-Ga-X (X=Fe, Co, and Cu) quarternary alloys, Fe atom prefers to occupy the Mn and Ni sublattices even in Ga-deficient alloys; Co has strong tendency to occupy the Ni-sublattice in all types of alloys; Cu atoms always occupy the sublattice of the host elements in deficiency. For most of the studied Ni-Mn-Ga and Ni-Mn-Ga-X alloys with stable site-occupations, the shear modulus C" can be considered as a predictor of the composition dependence of TM of the alloys: the alloy with larger C" than that of the perfect Ni2MnGa generally possesses lower TM except for Ni2Mn1+xGa1-x and Ni2Mn1-xGaFex. The failure of C" as a factor of TM in these two types of alloys may be ascribed that the compositiondependentmagnetic interactions and the temperature-dependent C0, which also playan important role on the martensitic transformation in these alloys. Furthermore, wedemonstrate that a proper account of the temperature and composition dependence ofC0 gives us reasonable theoretical TM(x) values in Ni2+xMn1-xGa alloys. Also in this type of Ni-rich and Mn-deficient alloys, by using the Heisenberg model in combination with the mean-field approximation, the abnormal trend of experimental magnetic transition temperature TC(x) with respect to the composition x is shown to be well captured by the theory. QC 20110830

We report an experimental investigation of the longitudinal space-time cross-correlation function of the velocity field, $C(r,��)$, in a cylindrical turbulent Rayleigh-B��nard convection cell using the particle image velocimetry (PIV) technique. We show that while the Taylor's frozen-flow hypothesis does not hold in turbulent thermal convection, the recent elliptic model advanced for turbulent shear flows [He & Zhang, \emph{Phys. Rev. E} \textbf{73}, 055303(R) (2006)] is valid for the present velocity field for all over the cell, i.e., the isocorrelation contours of the measured $C(r,��)$ have a shape of elliptical curves and hence $C(r,��)$ can be related to $C(r_E,0)$ via $r_E^2=(r-����)^2+��^2��^2$ with $��$ and $��$ being two characteristic velocities. We further show that the fitted $��$ is proportional to the mean velocity of the flow, but the values of $��$ are larger than the theoretical predictions. Specifically, we focus on two representative regions in the cell: the region near the cell sidewall and the cell's central region. It is found that $��$ and $��$ are approximately the same near the sidewall, while $��\simeq0$ at cell center., 16 pages, 15 figures, submitted to J. Fluid Mech

The type III secretion system (T3SS) is an essential requirement for the virulence of many Gram-negative bacteria which infect plants, animals and men. Pathogens use the T3SS to deliver effector proteins from the bacterial cytoplasm to the eukaryotic host cells, where the effectors subvert host defenses. The best candidates for directing effector protein traffic are the bacterial type III-associated appendages, called needles or pili. In plant pathogenic bacteria, the best characterized example of a T3SS-associated appendage is the HrpA pilus of the plant pathogen Pseudomonas syringae pv. tomato DC3000. The components of the T3SS in plant pathogens are encoded by a cluster of hrp (hypersensitive reaction and pathogenicity) genes. Two major classes of T3SS-secreted proteins are: harpin proteins such as HrpZ which are exported into extracellular space, and avirulence (Avr) proteins such as AvrPto which are translocated directly to the plant cytoplasm. This study deals with the structural and functional characterization of the T3SS-associated HrpA pilus and the T3SS-secreted harpins. By insertional mutagenesis analysis of HrpA, we located the optimal epitope insertion site in the amino-terminus of HrpA, and revealed the potential application of the HrpA pilus as a carrier of antigenic determinants for vaccination. By pulse-expression of proteins combined with immuno-electron microscopy, we discovered the Hrp pilus assembly strategy as addition of HrpA subunits to the distal end of the growing pilus, and we showed for the first time that secretion of HrpZ occurs at the tip of the pilus. The pilus thus functions as a conduit delivering proteins to the extracellular milieu. By using phage-display and scanning-insertion mutagenesis methods we identified a conserved HrpZ-binding peptide and localized the peptide-binding site to the central domain of HrpZ. We also found that the HrpZ specifically interacts with a host bean protein. Taken together, the current results provide deeper insight into the molecular mechanism of T3SS-associated pilus assembly and effector protein translocation, which will be helpful for further studies on the pathogenic mechanisms of Gram-negative bacteria and for developing new strategies to prevent bacterial infection.

采用第一性原理计算研究了超硬材料z-BC 2 N的弹性各向异性性质、应力-应变关系、硬度及最小热导率性质。计算得到的晶体力学行为判据B/G为0.87, 泊松比为0.084, 普适弹性各向异性指数为0.09992。[100]晶向上最大拉伸强度达到180 GPa, 应变方向上最大剪切强度达到160 GPa, 维氏硬度值为77.07 GPa。基于Cahill模型得到的最小热导率为6.811 W/(m·K)。结果表明: z-BC 2 N是脆性材料且力学稳定性良好, 有非常高的拉伸强度、剪切强度, 体弹模量为各向同性, 杨氏模量各向异性程度不大。z-BC 2 N的最小热导率低于金刚石的最小热导率。

The elastic and optical properties of face-centered cubic IVB group transition metal nitrides such as TiN, ZrN, and HfN are calculated using the plane wave pseudopotential method based on first-principle density function theory. Electronic property is a combination of covalent, ionic, and metallic property. And band structures of these compounds show metallicities in the ground state. The obvious numerical differences between E[100] and E[111] indicate elastic anisotropy. The phenomena result in lattice distortions and microcracks in these metal nitride films. With red shift of pseudogap, the metallic properties of TiN, ZrN, and HfN are improved in turn. And the elastic and optical properties change with metallic properties improving:brittleness reduces, the degree of anisotropy increases, the critical energy between intraband and interband transitions increases, and the solar-optical selectivity decreases. So reducing the number of conduction electrons to strengthen covalency is an effective method to improve elastic isotropy and optical selectivity.

Objectives Strain imaging provides objective quantification of myocardium deformation, thus is a useful tool to detecting regional wall motion abnormalities caused by myocardial ischaemia. With the technologic advancement in real-time three-dimensional echocardiography, the three-dimensional speckle tracking echocardiography (3DSTE) based on high quality volume image has been developed very recently. We aim to investigate the value of the novel 3DSTE in detecting myocardial ischaemia. Methods Forty-six patients with acute coronary syndrome were included and received coronary angiography (CAG). Patients were divided into myocardial ischaemia group (with >70% coronary stenosis in at least one main branch) and control group (without >70% coronary stenosis) according to the results of (CAG). The conventional and 3D echocardiography was performed using a Vivid E9 ultrasound diagnosis platform (GE Vingmed Ultrasound, Chicago, US). Echo parameters were compared between groups. Ischaemic myocardium segments were defined as territory of coronary arteries with >70% luminal stenosis. ROC curve analysis was performed to evaluate the accuracy of wall motion score (WMS) and strain parameters for detecting ischaemic segments. Results CAG results showed 26 out of 46 patients had >70% coronary artery stenosis. Speckle tracking were achieved in 94.8% (741/782) segments, with a total of 102 segments classified as ischaemic. The myocardial ischaemia group had significantly lower LVEF (66.1%±6.6% vs 49.8%±12.0%, p Conclusions The novel AS derived by 3DSTE is a very accurate and reproducible index for detecting regional wall motion abnormalities caused by myocardial ischaemia.

Objectives Aortic valvular disease is a very common cause of heart failure and cardiac death. Non-invasive assessment of early stage cardiac dysfunction caused by aortic valvular diseases is of great diagnostic and prognostic importance. In this study, we aim to investigate the value of the state-of-the-art three-dimensional speckle tracking echocardiography (3DSTE) in detecting left ventricle (LV) remodelling and early stage cardiac dysfunction. Methods Sixty-nine patients with aortic valvular diseases and NYHA heart function class I or II as well as 48 age matched healthy controls were recruited. All patients received conventional echocardiography. Furthermore, real-time three-dimensional echocardiography (RT3DE) images were recorded and 3DSTE were performed using a commercial available ultrasound diagnostic system (Vivid E9, GE Vingmed Ultrasound, Chicago, US). The 3DSTE allows rapid semi-automatic measurement of longitudinal strain (LS), circumferential strain (CS), radial strain (RS), and a novel area strain (AS) which represent the recline of surface area of LV during contraction. Besides, LVEF and LV mass can also be measured during 3D strain analysis. Results Patients with aortic valvular diseases have significantly lower LVEF (54.5% vs 62.4%, p 2 vs 82.2 g/m 2 , p 0.05). As for the strain derived parameters, global LS (−15.5% vs −19.3%, p To investigate if the pressure and volume overload have differential impact on LV deformation, patients with aortic valvular diseases were further divided into aortic stenosis and aortic regurgitation sub-groups (n=39 and 30 respectively). One-way ANOVA showed all four strain parameters were different among the three groups (LS, p Reproducibility of 3D strain parameters were tested in 20 random selected patients. The inter-observer variability for global LS, CS, RS and AS is 6.2%, 7.4%. 7.9% and 4.3% respectively. Conclusions 3DSTE are useful to detect early stage heart dysfunction caused by aortic valvular diseases. LS is most vulnerable to pressure overload caused by aortic stenosis while CS is more sensitive to volume overload due to aortic regurgitation.