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The main exploitation process of heavy oil is cyclic steam huff and puff. Cyclic operation causes cumulative damage to thermal recovery casing and causes a large number of failures. Failure analysis shows that the main failure factor of thermal recovery casing is the low cycle fatigue process caused by thermal cycle, which results in the decrease of strength of casing material, thus causing casing fracture and failure. Based on the failure analysis results, the low cycle fatigue tests of 80SH thermal recovery casing steel under different temperature, strain, pre-strain and other conditions were carried out. The influencing factors, life prediction model and criterion of service safety of casing materials under thermal recovery service conditions were first proposed, which provides a strong theoretical basis for the service safety design theory of thermal recovery casing materials. The research shows that the strain limit and low cycle fatigue life are the two core issues of service life. Life predictions need to satisfy two criteria. The first is the strain criterion. The strain limit should be lower than the total strain during the long service life. And the second is the low cycle fatigue criterion, which satisfies the expectation of low cycle fatigue life under double conditions of strain amplitude and mean strain.

In recent years, China's investment in space technology and natural environment has been increasing. In recent years, China's investment in space technology and natural environment has been increasing. First of all, it must be the bionic robot with strong adaptability to explore the surfaces of the moon, Mars and other planets under an uncertain environment. Compared with wheeled or tracked robot, the standpoints of the legged robot are discrete points, which can select optimal supporting spots on the ground, so the legged robot is better, especially the legged robot with eight legs. And the walking robot based on connecting-rod has been widely used because of its simple structure and strong load capacity. Secondly, due to the wide use of computer in society as well as the fast development of integrated circuit, SCM is playing a greater role. It has a lot of functions, can work steadily, and can be used conveniently but with small volume and low price so many of them are applied in the control systems, but more applications in the automatic control system, data acquisition, military products as well as appliances and other fields. And according to the specific hardware structure and the object, using the software makes it more perfect. In this paper, we designed a walking robot adopted the structure of connecting-rot, and take the SCM LM298 as the core of controlling. The robot takes its operation by using the integrated chips of encoding and decoding. This walking robot has realized many functions such as walking, turning back, left and right.

By the Lagrangian multiplier and constraint variational derivative, a relationship between conserved quantities and multi-Hamiltonian structures is built. Making using the relation a method is founded to prove the infinite-dimensional Liouville integrability of evolution equations with continuous variables. As the application, the conservation laws of the Kundu equation are firstly obtained. Its conserved quantities are deduced for comparing by Fokas' method different from the method used in the existed literature. The integrability of the equation is proved through taking the conservation laws as a starting point.

Two hierarchies of isospectral and nonisospectral Gerdjikov–Ivanov equations are constructed. Conservation laws of the isospectral soliton hierarchy are explicitly derived from a specific Riccati equation that a ratio of two eigenfunctions satisfies. The corresponding K-symmetries and $$\tau $$-symmetries formulated from the isospectral and nonisospectral hierarchies constitute an infinite-dimensional $$\tau $$-symmetry algebra for the isospectral hierarchy.

Background Gastrin is an important gastrointestinal hormone produced primarily by G-cells in the antrum of the stomach. It normally regulates gastric acid secretion and is implicated in a number of human disease states, but how its function affects breast cancer (BC) development is not documented. The current study investigated the suppressive effects of gastrin on BC and its underlying mechanisms. Methods Serum levels of gastrin were measured by enzyme-linked immunosorbent assay (ELISA) and correlation between gastrin level and development of BC was analyzed by chi-square test. Inhibitory effects of gastrin on BC were investigated by CCK-8 assay and nude mice models. Expressions of CCKBR/ERK/P65 in BC patients were determined through immunohistochemistry (IHC) and Western blot. Survival analysis was performed using the log-rank test. Results The results indicated that the serum level of gastrin in BC patients was lower compared with normal control. Cellular and molecular experiments indicated that reduction of gastrin is associated with inactivation of cholecystokinin B receptor (CCKBR)/ERK/P65 signaling in BC cells which is corresponding to molecular type of estrogen receptor (ER) positive BC. Furthermore, we found that low expression of gastrin/CCKBR/ERK /P65 was correlated to worse prognosis in BC patients. Gastrin or ERK/P65 activators inhibited ER+ BC through CCKBR-mediated activation of ERK/P65. Moreover, combination treatment with gastrin and tamoxifen more efficiently inhibited ER+ BC than tamoxifen alone. Conclusions We concluded that low serum gastrin is related to increased risk of ER+ BC development. The results also established that CCKBR/ERK/P65 signaling function is generally tumor suppressive in ER+ BC, indicating therapies should focus on restoring, not inhibiting, CCKBR/ERK/P65 pathway activity. Electronic supplementary material The online version of this article (10.1186/s12885-018-4717-7) contains supplementary material, which is available to authorized users.

By using the Hirota bilinear form of the (2+1)-dimensional BKP equation, ten classes of interaction solutions between lumps and kinks are constructed through Maple symbolic computations beginning with a linear combination ansatz. The resulting lump-kink solutions are reduced to lumps and kinks when the exponential function and the quadratic function disappears, respectively. Analyticity is naturally guaranteed for the presented lump-kink solution if the constant term is chosen to be positive.

Background Ginkgo biloba (Gb) extracts have been used as a traditional Chinese medicine. Gb contains flavonoids, which are considered to be its active ingredients and have been used in the treatment of a variety of diseases. However, few scientific research studies on the side effects of flavonoid in Gb have been reported. Purpose The present study aimed to investigate the effect of bilobetin on the kidney of Sprague-Dawley (SD) rats. Study design and result In this study, rats were injected with 50 mg/kg of bilobetin, a biflavone isolated from Gb, for 7 days and aristolochic acid was used as positive controls. The results showed that the body weight and urine output of the rats were dramatically decreased, and urinary protein increased after the intraperitoneal injection of bilobetin compared with the control group. Bilobetin treatment showed vacuolar degeneration in the renal tubular epithelium, glomerular atrophy by histostaining, and podocyte fusion by electron microscopy. This study further showed that bilobetin promoted the trafficking of aquaporin 2 (AQP-2) onto the plasma membrane to achieve the function of urine concentration by in vivo study in rats and in vitro study in IMCD-3 cells. The redistribution of AQP-2 is due to increased expression of cGMP in IMCD-3 cells, which in turn promoted the phosphorylation of AQP-2 at site Ser-256. The proteinuria caused by bilobetin may be attributed to podocyte cell cycle arrest at G2/M transition, which is may associated with AKT and MAPK signaling. Conclusions The current study showed that bilobetin has some side effects on kidneys at a dose of 50 mg/kg in SD rats and provides insight into the potential detrimental effects of monomeric ingredients in Gb.

The formation mechanism of linear macro-segregation in Al–Cu–Mn–Ti alloy cylindrical shell casting was studied by characterizing samples by X-ray detection, microscopic examinations, composition analysis, and simulation of the heat transfer of Al–Cu–Mn–Ti alloy cylindrical shell casting in the solidification process. Numerical and experimental results indicated that linear macro-segregation always occurred in the portion of casting connected with the slit gating system, because of the great hot tearing tendency, the hot cracks formed could be fed by the melt through the slit gating system with an excellent temperature gradient and feeding angle. According to significant effect of floatation of lower density α-Al grains, the solute gradient was formed along the vertical direction of the slit gating system. The hot cracks near the bottom of casting were fed by melt with high concentration of Cu and so, they were cicatrized by the eutectic structure/α-Al + Al2Cu at a temperature of 548℃.

The experiments and numerical simulation were conducted for ZL205A aluminum alloy cylindrical shell casting. The formation mechanism of the linear segregation produced by the low pressure die casting (LPDC) process was investigated. And the heat transfer of the casting during solidification process was analyzed by simulation technique, resulting from the information of linear segregation obtained by plenty of experiments. The new linear segregation criterion was proposed through the simulation and experimental results. It was found that the melting metal with high Cu contents was feeding the crack shrinkage formed by the tearing under the effect of feeding pressure during the later solidification, which led to the formation of linear segregation. The control methods for the linear segregation were suggested based on the proposed mechanism. Finally, the criterion of linear segregation was confirmed by the production of the actual castings.

In the paper, Ablowitz—Ladik hierarchy with new self-consistent sources is investigated. First the source in the hierarchy is described as nn+1, where n is related to the Ablowitz—Ladik spectral problem, instead of the corresponding adjoint spectral problem. Then by means of the inverse scattering transform, the multi-soliton solutions for the hierarchy are obtained. Two reductions to the discrete mKdV and nonlinear Schrodinger hierarchies with self-consistent sources are considered by using the uniqueness of the Jost functions, as well as their N-soliton solutions.

The present study aimed to determine the mechanism by which low‑intensity intermittent negative pressure affects the differentiation and proliferation of human mesenchymal stem cells (MSCs). Alkaline phosphatase (ALP) activity, type I collagen and vascular endothelial growth factor (VEGF) were detected to analyze differentiation. MTT and flow cytometry were employed to measure proliferation and apoptosis. Western blot analysis was used to examine endoplasmic reticulum (ER) stress‑associated factors. This study was divided into two groups, including a normal group (without any treatment) and vacuum group (treated with a vacuum). There was a significant decrease in the proliferation of cells in the vacuum group. The number of cells in S phase was reduced significantly, while the rate of apoptosis and the activity of ALP were markedly increased under vacuum conditions. Expression of collagen type I and VEGF was significantly increased, and the ratio of osteoprotegrin to osteoprotegrin ligand was decreased significantly in the vacuum group. ER stress‑associated proteins, p‑PRKR‑like ER kinase, inositol‑requiring enzyme 1 and cleaved activating transcription factor 6, as well as the downstream factors, were activated when treated with negative pressure. In conclusion, treatment with low‑intensity and intermittent negative pressure may inhibit the proliferation of MSCs and trigger ER stress‑associated cellular apoptosis, further enhancing osteogenesis activity and inducing differentiation to osteoblasts.

Multisoliton solutions are derived for a general nonlinear Schrödinger equation with derivative by using Hirota’s approach. The dynamics of one-soliton solution and two-soliton interactions are also illustrated. The considered equation can reduce to nonlinear Schrödinger equation with derivative as well as the solutions.

Purpose To provide a summary of the relevant evidence on outcomes of transaxillary first rib excision (TAFRE), supraclavicular first rib excision with scalenectomy (SCFRE), and supraclavicular release leaving the first rib intact (SCR) for patients with neurogenic thoracic outlet syndrome (TOS), and interpret the treatment effects from a Bayesian perspective. Methods A systematic literature search and review were performed. Random-effects meta-analyses were conducted to estimate success rate and complete relief rate of each procedure. The probabilities of specified success rates and complete relief rates were calculated using a Bayesian method. Sensitivity analyses for TOS type, neck trauma, and cervical rib were performed. Complications of each procedure were also reviewed. Results Data were extracted from 17 studies of TAFRE, 9 of SCFRE, and 14 of SCR to conduct the meta-analyses. The pooled success rate and complete relief rate were 0.76 (95% confidence interval [95% CI)], 0.65–0.85) and 0.53 (95% CI, 0.38–0.68) for TAFRE, 0.77 (95% CI, 0.68–0.85) and 0.57 (95% CI, 0.41–0.72) for SCFRE, and 0.85 (95% CI, 0.76–0.92) and 0.61 (95% CI, 0.35–0.84) for SCR, respectively. The probabilities of success rate greater than 70% were 90%, 87%, and 99% for TAFRE, SCFRE, and SCR, respectively. If the success rate of 80% or greater was considered, the probabilities were 34%, 31%, and 91%, respectively. The probabilities of complete relief rate of 50% or greater were 67%, 71%, and 69% for TAFRE, SCFRE, and SCR, respectively. Sensitivity analyses showed similar results. The complication rates for TAFRE, SCFRE, and SCR were, respectively, 22.5%, 25.9%, and 12.6%. Conclusions The SCR has a high probability of success rate greater than 80%; both TAFRE and SCFRE have high probabilities of a success rate greater than 70% but only low probabilities of success rate greater than 80%. The TAFRE and SCFRE have more complications than SCR. Type of study/level of evidence Therapeutic IV.

Generalized matrix exponential solutions to the coupled derivative nonlinear Schrödinger equation (DNLSE) are obtained by the inverse scattering transformation (IST). The resulting solutions involve six matrices, which satisfy the coupled Sylvester equations. Several kinds of explicit solutions including soliton, complexiton, and Matveev solutions are deduced from the generalized matrix exponential solutions by choosing different kinds of the six involved matrices through Mathematica symbolic computations.

In this paper, a modified Michelson interferometer is designed to measure Terahertz spectrum. Compared with normal Michelson interferometer, hollow retroreflectors are used instead of flat mirrors as reflective mirrors. The theory analysis and some measurement are given.

The need for understanding and assessing soil quality is getting increasingly important because of growing public interest in determining the effect of management practices on the sustainability of the soil resource base. Our objectives were to investigate the effect of consecutive cultivation and different rotation systems on potential soil quality indicators, to identify effective soil quality indicators and to establish a minimum data set that discriminate different rotation systems. This study was conducted in a typical coastal salt-affected farmland in north Jiangsu Province, China. A pool of 22 measured variables representing soil chemical and physical properties (0–10 cm) and groundwater features at 60 sampling sites and 10 representative soil profiles were used. A specific emphasis was given to the impact of crop rotation systems on measured soil and groundwater properties because of the importance of cultivation to the sustainability of soil quality. One-way analysis of variance (ANOVA) showed that measured variables of SOM, SOCD, TN, AP, CEC, AK, ECe, Na and Cl were positively impacted by cultivation. In contrast to cotton–barley rotation, rice–rape rotation had significantly positive influence on SOM and SOCD, but adverse impact on AK, pH, ρb, Ks, WTg and ECg. Factor analysis grouped all measured variables into seven principal components explaining 78.5% of total variance: salinity (PC1), organic matter (PC2), water permeability (PC3), soil texture (PC4), ion exchange (PC5), soil alkalinity (PC6) and available nutrients (PC7). Discriminant analysis indicated that PC1 (Cl, Na and ECg), PC2 (SOM and SOCD) and PC7 (WTg) were the most powerful factors (indicators) to distinguish the two rotation systems. SOCD (SOM) and Cl offered the greatest potential for monitoring soil quality under different management practices. SOM not only had the strongest positive influence on crop biomass, but also contributed the greatest to distinguishing the effect of rotation systems on soil quality. Our study suggested that SOM may be considered as an indispensable factor to determine the sustainability of soil productivity for the salt-affected farmlands in coastal reclamation area.

The non-isospectral Ablowitz–Ladik hierarchy is integrated by the inverse scattering transform. In contrast with the isospectral Ablowitz–Ladik hierarchy, the eigenvalues of the non-isospectral Ablowitz–Ladik equations in the scattering data are time-dependent. The multi-soliton solution for the hierarchy is presented. The reductions to the non-isospectral discrete NLS hierarchy and the non-isospectral discrete mKdV hierarchy and their solutions are considered.

To offer those who are engaged in oil development a multi-objective design method of borehole trajectory for a directional well, the author adopted optimization theory to build a multi-objective optimization mathematic model with the shortest trajectory, the lowest drill string torque and the minimum rig hook load as final objectives, and put forward an approach to seek effective solutions to these multi-objective programming problems with ideal point method. The approach proposed in the paper can help satisfy concurrently multiple objectives of drilling design for an oilfield to implement the multi-objective optimization design schemes of borehole trajectory for a directional well, and to reduce the oilfield development costs accordingly.

To find out the cause for fatigue failure of a drill string used in oil field drilling, and considering the actual working conditions, axial, radial and circumferential cyclic stresses borne by the drill string in borehole of oil and gas well, fatigue strength of drill string is analyzed based on multi-axial fatigue assessment method. Then the formula to calculate the mean stress of multi-axial load of the drill string is obtained, and the formula serves as a method to calculate multi-axial fatigue life of the drill string, which has been verified through field data. It is realized that multi-axial stress has significant influence on drill string fatigue. When on drill string fatigue, Soderberg equation shall be employed to calculate the stress amplitude of drill string fatigue.

The paper investigates the mKdV equation with the potential under symmetry constraint through bilinear approach, i.e., Hirota method and Wronskian technique. We show that the potential can be a summation of squares of wave functions and these wave functions can precisely be described as Wronskians.

In this paper, threaded joint dedicated for the solid expandable tubular is taken as the basic structure and specific parameters for the threaded joint is set. 16Mn improved material is selected as the material, and MSC/Marc software is adopted to conduct finite element analog study on technical performance of the threaded joint and to analyze the distribution and strain condition of microstress and macrostress for the thread after make-up as well as the tensile strength and sealing property for the joint after make-up. Multiple important data concerning the designed expandable tubular threaded joint have been obtained through the study. It is convinced that the solid expandable tubular threaded joint shall adopt be a flush one with both internal and external walls parallel and level with the tubular body, and the type of thread shall take a shape of reversed hook. Besides, the expandable tubular threaded joint shall adopt the sealing structure with the rubber seal as the main sealing type and metallic seal auxiliary.

The effect of CO2 on seal capacity of cement mantle causes casing corrosion and reduces the life of oil well. The corrosion proof of cement system is studied to improve the integrity and seal properties of the cement stone under acidic medium. The CO2 corrosion test of 5 blocks cement under high temperature and high pressure was conducted. Compressive strength, permeability and corrosion depth were measured and morphology after corrosion was observed by scanning electron microscope. A density cement slurry formulations was selected by analyzing the experimental data. It not only has excellent corrosion resistance, but also has properties of anti-gas breakthrough, reduction of free water and stability. It can meet cementing requirement of different well depth conditions.

The performance of solid expandable tubular threaded joint is affected by complicated factors such as material property change, large deformation of geometric dimension and residual stress. Given material nonlinearity, geometrical nonlinearity and contact nonlinearity in the operational process of solid expandable tubular threaded joint, MSC/Marc software was adopted in this paper to conduct simulation study on the sealing property of the threaded joint during expansion and joint strength of the threaded joint after expansion. It was recognized that the solid expandable tubular threaded joint should adopt hook-shaped thread with a negative angle for the bearing surface, the sealing property of metal-to-metal cone seal would decline after expansion of the joint, and the solid expandable tubular threaded joint ought to adopt the rubber-seal-orientated sealing form. Furthermore, it was also found out that the internal thread and the root of the external thread were the vulnerable parts of the solid expandable tubular threaded joint, and the joint would first break down and cease to be effective on these parts under excessive tensile load.

The Von Mises equivalent stress criteria is used to equivalent convert and correct the uniaxial and biaxial fatigue reliability experimental study of the casing material. And the probabilistic fatigue P–S–N curve of the casing is gained. The fatigue limit and fatigue life in test is equivalent convert to actual casing by combined stress correction factor. A multiaxial fatigue life calculation formula is proposed by correcting the probabilistic fatigue P–S–N curve.

In this paper, hierarchies of multi-component AKNS–Kaup–Newell equations are derived, including positive nonisospectral AKNS–Kaup–Newell hierarchy and negative nonisospectral AKNS–Kaup–Newell hierarchy. Moreover, new integrable couplings of the resulting AKNS–Kaup–Newell soliton hierarchies are constructed by enlarging the associated matrix spectral problem.

We discuss a symmetry of the Korteweg–de Vries (KdV ) equation. This symmetry can be related to the squared eigenfunction symmetry by a limit procedure. As applications, we consider the similarity reduction of the KdV equation and a KdV equation with new self-consistent sources. We derive some solutions via a bilinear approach.

Imaging protocols for suspected scaphoid fractures among investigators and hospitals are markedly inconsistent. We performed a systematic review and meta-analysis to assess and compare the diagnostic performance of bone scintigraphy, MRI, and CT for diagnosing suspected scaphoid fractures. Twenty-six studies were included. Sensitivity, specificity, and diagnostic odds ratio were pooled separately and summary receiver operating characteristic curves were fitted for each modality. Meta-regression analyses were performed to compare these modalities. We obtained likelihood ratios derived from the pooled sensitivity and specificity and, using Bayes’ theorem, calculated the posttest probability by application of the tests. The pooled sensitivity, specificity, natural logarithm of the diagnostic odds ratio, and the positive and negative likelihood ratios were, respectively, 97%, 89%, 4.78, 8.82, and 0.03 for bone scintigraphy; 96%, 99%, 6.60, 96, and 0.04 for MRI; and 93%, 99%, 6.11, 93, and 0.07 for CT. Bone scintigraphy and MRI have equally high sensitivity and high diagnostic value for excluding scaphoid fracture; however, MRI is more specific and better for confirming scaphoid fracture. We believe additional studies are needed to assess diagnostic performance of CT, especially paired design studies or randomized controlled trials to compare CT with MRI or bone scintigraphy. Level of Evidence: Level III, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.

Ultrafine grain WC hardmetals were manufactured successfully from mixed powders of nominal composition of WC-6Co-1.5Al(wt%). To manufacture bulk ultrafine grain WC alloys, nanocrystalline WC powders as precursor were prepared for sintering from the mixed commercially available powders by high energy milling of 15 h. Then the electrical current sintering process of the milled powders was further studied. Experimental results showed that the density, hardness and transverse rupture strength of the sintered alloys reached 14.224 g/cm3, HRA 94 and 1660 MPa, respectively, by a appropriate coupling of pulse- and subsequent constant-current sintering and with the total sintering time of 6 min. It seemed difficult to obtain desirable sintered hardmetal by a single type of electric current sintering. However, the application of intensive pulse electric current was favorable to sintering, although it was difficult to achieve good WC alloys only by the pulse electric current sintering. A higher density WC alloy could be prepared by enlarging the electric current when only constant electric current was applied to sinter the milled powders. Unfortunately, the WC grains substantially coarsened concurrently so that the mechanical properties of the as sintered alloy decreased obviously.

A simple laboratory technique for the routine preparation of antimony-doped tin oxide (ATO) on float glass substrates (25×76×1mm3) was described. The process employed sol-gel dip-coating approach in the absolute ethanol solution of metal salts of tin (II) chloride dehydrate and antimony trichloride. Microstructural and morphological analyses of as-prepared films were performed at different conditions. With increase of annealing temperature from 400 to 550°C, the evolution of grain size and the morphologies of ATO films were analyzed by means of atom force microscopy (AFM). The studies on the morphological development suggested that higher annealing temperature led to a decrease in the surface roughness of the deposited films. The XRD patterns revealed that as-prepared ATO films were in the crystallization of a tetragonal rutile structure of SnO2 with highly (110) preferred orientation.

Antimony-doped tin oxide (ATO) transparent conducting thin films were prepared by sol-gel dip-coating technique in the alcohol solution of metal salts of tin (II) chloride dehydrate and antimony tri-chloride. Usual glass slides (25×76×1mm3) were used as the substrates. As-prepared thin films were dried at temperature of 343K and annealed at temperatures of 673~823K. Their optical properties were analyzed by Hitachi U-3310 spectrophotometer. The good optical transmission of the ATO thin films has been obtained as high as 80%-90% in visible region by the optimization of deposition conditions, but decreased substantially in IR region. From the X-ray diffraction (XRD) measurements, it showed that ATO films had the similar structures with the pure tin oxide films, i.e. tetragonal rutile structure, despite of some rhombic SnO crystals. We analyzed the transmittance in the visible region depending on the vary Sb doped level, temperature, and dip-coating times. The sheet resistance of the investigated thin films was determined by four-probe method, showing that it was about 85-1009/□, which decreased with the increase of antimony doped concentration.

The aim of this study was to assess the cost effectiveness of multiple competing diagnostic strategies for suspected scaphoid fractures.With published data, the authors created a decision-tree model simulating the diagnosis of suspected scaphoid fractures. Clinical outcomes, costs, and cost effectiveness of immediate computed tomography (CT), day 3 magnetic resonance imaging (MRI), day 3 bone scan, week 2 radiographs alone, week 2 radiographs-CT, week 2 radiographs-MRI, week 2 radiographs-bone scan, and immediate MRI were evaluated. The primary clinical outcome was the detection of scaphoid fractures. The authors adopted societal perspective, including both the costs of healthcare and the cost of lost productivity. The incremental cost-effectiveness ratio (ICER), which expresses the incremental cost per incremental scaphoid fracture detected using a strategy, was calculated to compare these diagnostic strategies. Base case analysis, 1-way sensitivity analyses, and "worst case scenario" and "best case scenario" sensitivity analyses were performed.In the base case, the average cost per scaphoid fracture detected with immediate CT was $2553. The ICER of immediate MRI and day 3 MRI compared with immediate CT was $7483 and $32,000 per scaphoid fracture detected, respectively. The ICER of week 2 radiographs-MRI was around $170,000. Day 3 bone scan, week 2 radiographs alone, week 2 radiographs-CT, and week 2 radiographs-bone scan strategy were dominated or extendedly dominated by MRI strategies. The results were generally robust in multiple sensitivity analyses.Immediate CT and MRI were the most cost-effective strategies for diagnosing suspected scaphoid fractures.Economic and Decision Analyses Level II. See Instructions for Authors for a complete description of levels of evidence.

In many learning tasks with structural properties, structural sparsity methods help induce sparse models, usually leading to better interpretability and higher generalization performance. One popular approach is to use group sparsity regularization that enforces sparsity on the clustered groups of features, while another popular approach is to adopt graph sparsity regularization that considers sparsity on the link structure of graph embedded features. Both the group and graph structural properties co-exist in many applications. However, group sparsity and graph sparsity have not been considered simultaneously yet. In this paper, we propose a g2-regularization that takes group and graph sparsity into joint consideration, and present an effective approach for its optimization. Experiments on both synthetic and real data show that, enforcing group-graph sparsity lead to better performance than using group sparsity or graph sparsity only.

‘Chemically pure’ Ag colloids were prepared by laser ablation of Ag plate in pure water. The Ag colloids have good stability and the Ag nanoparticles in the colloids have homogeneous size distribution. Compared with the Ag colloids produced by chemical reduction methods, there was no any extraneous component ions in the colloids produced by laser ablation. Synchronously, we obtained much higher quality SERS spectra of PHBA molecules in the Ag colloids produced by laser ablation, the study of the adsorption behavior of p-hydroxybenzoic acid (PHBA) in the Ag colloids by surface-enhanced Raman scattering (SERS) indicated that the Ag colloids system was highly efficient substrate for SERS investigation.

Bilinear forms of the coupled Gerdjikov–Ivanov equation are derived. The N-soliton solutions to the equation are obtained by Hirota's method. It is interesting that the two-soliton solutions can generate the rogue-wave-like phenomena by selecting special parameters. The equation can be reduced to the Gerdjikov–Ivanov equation as well as its bilinear forms and its solutions.

to investigate if the cartilaginous surface and corresponding osseous contour of the patellofemoral joint match in the axial plane for providing theoretical basis with evaluating alignment of patellofemoral joint and designing the part of patellofemoral joint in knee prosthesis.from January 2009 to March 2010, 9 human cadaver knees were prepared, which chandra of patellofemoral joint didn't degenerate. Each specimen was sectioned in the axial plane at 20° to 30° knee flax. The cross-sections revealed characteristics in the bony anatomy and corresponding articular surface geometry of the patellofemoral joint in the axial plane. Evaluating parameters included osseous patella congruence angle (OPCA), chondral patella congruence angle (CPCA), patella chondral convex point parameter (PCCPP), patella subchondral osseous convex point parameter (PSOCPP), the parameters of the deepest (chondral or osseous) point of the intercondylar sulcus. After that, the osseous and cartilaginous contours and subchondral osseous contours of the patella in the axial plane were analyzed through MRI data of 11 patients who didn't degenerate in patellofemoral joint cartilage. Parameters as same as cadaver knees were compared.data from specimens of OPCA was (-4.5 ± 1.1)°, CPCA was (0.5 ± 0.8)°, PCCPP was 1.13 ± 0.11, PSOCPP was 1.67 ± 0.14, PCDPIS was 1.35 ± 0.28, PODPIS was 1.38 ± 0.33. Date from MRI of OPCA was (-3.8 ± 1.4)°, CPCA was (0.7 ± 1.0)°, PCCPP was 1.05 ± 0.21, PSOCPP was 1.73 ± 0.18, PCDPIS was 1.41 ± 0.21, PODPIS was 1.37 ± 0.27. The patella exhibited significant differences in the bony vs. chondral anatomy (P0.05), but the intercondylar sulcus nearly match in the bony vs. chondral anatomy.the cartilaginous surface and corresponding osseous contour of the patella don't match in the patellofemoral joint axial plane, but that of the trochlea nearly matches. This is very important for accurately evaluating alignment of patellofemoral joint because the normal osseous alignment of patellofemoral joint don't represent the normal alignment and helpful for designing the part of patellofemoral joint in knee prosthesis.

The relationship of stomach cancer susceptibility and the presence of E-cadherin (CDH1) promoter -160 C/A polymorphism had been reported with conflicting results. To further explore the association of this polymorphism with stomach cancer susceptibility, we performed an extensive search of relevant studies and carried out a meta-analysis to obtain a more precise estimate. A total of 16 studies including 2,611 cases and 3,788 controls were involved in this meta-analysis. When all studies involved, the meta-analysis results suggest no statistically significant association between CDH1 -160 C/A polymorphism and stomach cancer risk (CA vs. CC: OR = 1.01, 95% CI: 0.85-1.19; AA vs. CC: OR = 1.05, 95% CI: 0.75-1.46; dominant model: OR = 1.02, 95% CI: 0.86-1.20; recessive model: OR = 1.04, 95% CI: 0.76-1.41). When subgroup analyses were performed by ethnicity, the A-allele carriers conferred a decreased stomach cancer risk in Asians (AA vs. CC: OR = 0.67, 95% CI: 0.47-0.96; dominant model: OR = 0.85, 95% CI: 0.72-0.99), but no statistically significant association was found in Caucasians. In conclusion, this meta-analysis suggests that CDH1 -160 A-allele may play a protective role of stomach cancer development in Asians but not in Caucasians.

To evaluate the safe zones of screw fixations of Jumbo cup and reinforcement rings in acetabular revision surgery.From December 2006 to January 2008, 11 fresh frozen human cadaver pelvises were prepared by removing all soft tissues except the medial neurovascular structures, each specimen was held in supine position with clamps. The anteroposterior radiographs were taken after the Jumbo cups or reinforcement rings were fixed in places. Left sides of acetabulum were used to create the models to evaluate the safe zones of the high hip center and Jumbo cups. Right sides were used to evaluate the safe zones of 3 different designs of acetabular reinforcement rings (Müller, Ganz, Burch-Schneider cage).Jumbo cups: screws in the superoanterior and anteroinferior quadrants could cause neurovascular injuries. High hip center: neurovascular injuries could be expected in all quadrants except the inferoposterior and posterior half of superoposterior quadrant. Müller ring: screws placed in the intra-acetabular and extra-acetabular areas of the superoanterior quadrant could cause neurovascular injuries. Ganz ring:the screws placed in superoanterior quadrant and apex area were dangerous. The insults were confirmed in all of the specimens. Burch-Schneider cage: the medial nervous and vasculature structures were injured in all of the specimens if the screws placed in the superoanterior (intra-acetabular and extra-acetabular) quadrant. Screws for ischial fixation could cause sciatic nerve injury.In revision acetabular surgery, the superoanterior quadrant, the anterior half of the superoposterior quadrant and the implant's central area are unsafe for screw fixation, especially when the exposed thread is longer than 15 mm.