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Elucidating the structural variations of lignin during the pretreatment is very important for lignin valorization. Herein, poplar wood was pretreated with an integrated process, which was composed of AlCl

AIM: To compare the wavefront aberrations and corneal surface regularity between dry eye (DE) patients and normal subjects and assess its diagnostic performance for DE measured with OPD Scan-III. METHODS: Fifty right eyes of 50 DE patients and 31 right eyes of normal subjects were included. The examinations for ocular surface including logarithm of the minimum angle of resolution best-corrected distance visual acuity (logMAR BCVA) the ocular surface disease index (OSDI), tear film break-up time (TBUT) and corneal fluorescein staining (CFS). OPD Scan-III was used to measure anterior corneal aberrations including total corneal aberrations, high order aberration (HOA), coma, trefoil, spherical aberration (SA), standard deviation of corneal power (SDP), surface regularity index (SRI) and surface asymmetry index (SAI). Statistical analysis were assessed with nonparametric tests and Spearman's correlations. All parameters were also analyzed for sensitivity, specificity, and receiver operating characteristics (ROC) curves. RESULTS: Wavefront aberrations parameters including total corneal aberrations, HOA, coma, trefoil, and SA in DE group were significantly higher than those in normal group (P

This paper focuses on the spotlight synthetic aperture radar (SAR) imaging for point scattering targets based on tensor modeling. In a real-world scenario, scatterers usually distribute in the block sparse pattern. Such a distribution feature has been scarcely utilized by the previous studies of SAR imaging. Our work takes advantage of this structure property of the target scene, constructing a multi-linear sparse reconstruction algorithm for SAR imaging. The multi-linear block sparsity is introduced into higher-order singular value decomposition (SVD) with a dictionary constructing procedure by this research. The simulation experiments for ideal point targets show the robustness of the proposed algorithm to the noise and sidelobe disturbance which always influence the imaging quality of the conventional methods. The computational resources requirement is further investigated in this paper. As a consequence of the algorithm complexity analysis, the present method possesses the superiority on resource consumption compared with the classic matching pursuit method. The imaging implementations for practical measured data also demonstrate the effectiveness of the algorithm developed in this paper.

The positive magnetoresistance (MR) usually appears at cryogenic temperature in ZnO-based transport systems, the origin of which is reported to be related to the localized magnetic moment. Here we find a different origin of the positive MR in Zn1−x Mg x O/ZnO heterostructures prepared by magnetron sputtering. The large positive MR is observed in all samples at 2 K. On increasing temperature, the observed positive MR is gradually suppressed and transformed into the negative MR at higher temperature. Similarly, the suppression of the positive MR also occurs in the samples with the higher electron density. The experimental data can be well described by applying a two-band model combined with the weak localization (WL) theory. This indicates that the observed positive MR originates from the impurity-band-related two-band transport, while the observed negative MR arises from the WL.

Introduction: Spontaneous cerebrospinal fluid leakage is usually caused by developmental abnormalities and is rare, accounting for approximately 5% of the cases of cerebrospinal fluid (CSF) leakage.[1] To the best of our knowledge, clival dysplasia-caused CSF rhinorrhea has never been reported in the neurosurgical field. Conclusion: Spontaneous cerebrospinal fluid rhinorrhea is often treated by surgery, and a transsphenoidal approach repair is the main surgical method used, offering the advantages of less trauma, fewer complications, rapid postoperative recovery, and low recurrence rate.

This paper discusses the method of Two-Dimensional Angle-Of-Arrival (2-D AOA) estimation of an L-shaped array based on a tensor decomposition algorithm. The proposed method achieves a high-resolution performance with the assistance of the multiple invariance modeling and the uniqueness property of tensor decomposition. Not only for uncorrelated signals, the tensor-decomposition-based method is also capable to process coherent signals. The authors adopt a modified L-shaped array configuration in which the azimuth and elevation angles can be exploited independently. Moreover, by such configuration, the Cross Correlation Matrix (CCM) is employed to accomplish pair-matching between estimated parameters of both axes. Numerical simulations verified the effectiveness of the proposed method.

The structural characteristics of the tensioning device in the wire saw manufacturing equipment is introduced. Based on the characteristic of the strainer, the principle of variable universe fuzzy control is adopted to deal with the controlling objects. The design of two stage fuzzy controller and its parameters are discussed. The system simulation shows that the control scheme can make the tension within the stable range.

In this paper, a compounding pressure sensing structure of Fiber Bragg Grating (FBG) based on circular plate diaphragm and equal strength cantilever is proposed. Based on mechanics of materials principle and mode coupling theory, a linear expression between uniform pressure and central wavelength shift of fiber grating fixed on the surface of the cantilever has been achieved. The pressure shift of fundamental modes resonance wavelength is investigated by means of simulation method. The results show that the resonance wavelengths are linearity increased with ambient pressure. The conclusion is of great aid to the application of the fiber Bragg grating.

Based on mode coupling theory, Tilted Fiber Bragg Grating temperature sensing principle and the characteristics of transmission spectra have been proposed. The temperature shift of fundamental modes resonance wavelengths and high-order modes resonance wavelengths were investigated by means of simulation method. The tilted angle on the effect of resonance wavelengths was discussed. The results show that the different resonance wavelengths are linearity increased with ambient temperatures. The fundamental modes are more sensitive than the high-modes ones. The conclusion has certain significance for TFBG fabrication.

The adsorption of H2S molecule on Si-doped and Ag supported Si-doped graphene is studied by first-principles calculations. We find that the H2S floats on the Si-doped graphene sheet, indicating a weak physisorption. The calculated net charge transfer, charge density difference and density of states give evidence that the adsorption of H2S on Ag supported Si-doped graphene is by chemisorption. Moreover, the desorption and dissociation of H2S adsorbed on Ag supported Si-doped graphene occur at the external electric field of 1.4 and -0.8 V/Å, respectively. Therefore, the Ag supported Si-doped graphene can be expected to be a novel sensor for the detection of H2S gas.

This paper introduces the structure of the resin bonded abrasive wire saw manufacture equipment. The equipment can complete the process of the wire saw production, including uncoiling wire, cleaning wire, binder coating, Pre-curving and coiling wire. Wire saw are manufactured successfully by this equipment in the manufacture experiment. The quality of the wire saw was examined by SEM. The average slicing ability of the wire saw is 205 mm2 per meter in the experiment of KDP crystal slicing.

A wire-saw cut KDP crystal geometrical model was founded and a mathematical model was established to calculate the grit average cut depth, based on indentation fracture mechanics theory(IFMT). The relationship between the grit cut depth and wire saw process parameter was analyzed theoretically. The research results indicate that there exists an approximate monotone increasing non-linear correlation between grit average cut depth and the ratio i value of crystal feed speed and wire speed. By increasing the wire speed and crystal feed speed accordantly, the value of i can be maintained invariable, however, this way can simultaneously bring higher machined surface quality and machining efficiency.

Carbon nanotubes (CNTs) is a well thermal transport nano materials, however, the thermal conductivity of CNTs has not been well established, only a few groups had reported experimental data and the existed simulation results ranged widely. Specially, the conclusions in low temperature section and dynamic structures were not very clearly. In this paper, the methods based on phonon scattering theory were applied to explore the thermal transport properties CNTs. The investigation was carried out under the conditions of temperature and axial strain. In the consideration of quantum effect, the thermal conductivity increased linearly with the growth of temperature in low-temperature section, and began to decrease gradually when the temperature exceeded a definite value. If an axial strain was concerned, there was an increasing trend of thermal conductivity as the stretch strain increases. However, after the strain exceeded a particular value the thermal conductivity decreased significantly. In addition, the high frequency phonon peak in PDOS was found to be an important parameter in describing thermal transport properties of dynamic structures.

A mathematical model to calculate the grit average cut depth in wire sawing single crystal silicon was founded. So the grit average cut depths were calculated theoretically by choosing different process parameters, and influences of process parameters on grit cut depths of slicing silicon crystal were analyzed. Analysis results indicate that the grit average cut depth relates to the silicon mechanical properties, grit shape and size, wire speed and ingot feed speed, etc. And there is a monotone increasing non-linear correlation between grit average cut depth and the ratio i value of ingot feed speed and wire speed, when the i value is lower, the average grit cut depth is lower.

The grinding heat is utilized to induce martensitic phase transformation and strengthen the surface layer of AISI 5140 alloy steel by raising surface temperature higher than austenitic temperature and cooling quickly. The grinding temperature field is simulated by using finite element method (FEM). Then, the hardness penetration depth (HPD) is predicted from the temperature history and martensitic phase transformation conditions in surface grinding. The experiments of different grinding parameters are performed in surface grinding lathe. The hardness and hardness penetration depth of work piece surface layer are measured to validate the simulation and prediction. This method can be used to predict the HPD and optimize the grinding parameters forwardly.

Based on reciprocating electroplated diamond wire saw (REDWS) slicing experiments, a study on REDWS machining brittle-ductile transition of single crystal silicon was introduced. The machined surfaces and chips were observed by using Scanning Electron Microscope (SEM), and some experimental evidences of the change of material removal mode had been obtained. The experimental results indicate there is a close relationship between material removal mode and the ratio r value of ingot feed speed and wire speed, through controlling and adjusting the r value, the material removal mode can be complete brittle, partial ductile and near-ductile removal.

Based on reciprocating electroplated diamond wire saw slicing single crystal silicon experiments, a bonded interface sectioning technique was used to measure the silicon subsurface damage (SSD) depth, and the influences of wire saw speed and feed speed on silicon SSD were studied. Moreover, based on the indentation fracture mechanics (IFM) theory, a theoretical model of relationship between SSD and surface roughness (SR) was established for predicting the SSD depth by measuring the SR. The results indicate that SSD depth decreases with the wire saw speed increase and feed speed decrease, within the range of experimental technical parameters. There exists monotone increasing non-linear correlation between SSD depth and SR (Rz) in wire saw slicing single crystal silicon, that is, SSD－SR+χSR3/4. And the experimental measure values coincide with the theoretical prediction values comparatively, therefore, the theoretical model can be used for predicting SSD depth rapidly, expediently and accurately.

Development of high performance diamond impregnated wire is the key of application for fixed-abrasive wire sawing technology. In this paper, some experimental studies were done for development of electroplated diamond wire saw by employing the bright nickel bath. The wire saw electroplating process was developed, the effects of cathode current density and time at tack-on stage on diamond grits density and adhesion between saw matrix and plating coating were discussed. The wire saw cutting experiments were carried out for analysis the used wire wear using the scanning electron microscope (SEM). The experimental results show the optimum tack-on current density to obtain the wire saw with good abrasive distribution and adhesion is 1.5~2.0A/dm2, and the time of pre-plating, tack-on and buildup is 6, 8~10 and 18min in turn. Diamond wire saw wear includes coating wear and grain-abrasion, and the primary wear form is grits pulled-out.

The physical model of fixed-abrasive diamond wire-sawing monocrystalline silicon was founded to analyze the elastic deformation of the wire, supposing that every grit was connected to the surface of the wire by a spring. Ignoring lateral vibration of the wire, the geometrical model of wire-sawing was founded; the average cut depth of single grit was calculated theoretically. Based the indentation fracture mechanics and investigations on brittle-ductile transition of machining monocrystalline silicon, the removal mechanism and surface formation was studied theoretically. It shows that in the case of wire-sawing velocity of 10m/s or higher, infeed velocity of 0.20mm/s and diamond grain size of 64μm or smaller, the chip formation and material removal is in a brittle regime mainly, but the silicon wafer surface formation is sawed in a ductile regime. The size of the abrasives, the wire-saw velocity and infeed velocity can influence the sawing process obviously.

To study the safety and survival outcome of surgical management for elderly gastric cancer patients.Patients proven of gastric cancer who aged 80 years during November 2002 to July 2011 were retrospectively analyzed. The detailed information of patients' characteristics and surgical management was retrieved. Follow-up of overall survival status was performed to analyze the surgical effectiveness.Totally, 92 (48 in surgery and 44 in non-surgery group) out of 187 eligible patients recorded adequate information and analyzed finally. Median ages were 81 years in surgery group and 83 year in non-surgery group. There were 34 patients undergone radical gastrectomy, 6 palliative gastrectomy, 1 gastrojejunostomy and 7 exploratory laparotomy. Median follow-up durations were 25 (9-111) and 28 (8-114) months in surgery and non-surgery groups, respectively (p = 0.797). Clinical-pathological T stage was 6 T1, 5 T2, 14 T3 and 23 T4 cases for surgery and 7 T1, 6 T2, 3 T3, 7 T4 and 21 TX cases for non-surgery. Clinical-pathological node status was 18 N0, 7 N1, 6 N2, 7 N3 and 10 NX cases for surgery and 10 N0, 3 N1, 3 N2, 3 N3 and 25 NX cases for non-surgery. Clinical-pathological distal metastasis status was 15 and 26 M1 cases for surgery and non-surgery, respectively (p = 0.006). Incidence of postoperative complications was 25.0% and postoperative hospital mortality was 2.1%. The 2-year survival rates were 30.8% and 8.0% for surgery and none-surgery, respectively (HR = 3.023, p = 0.001), and the 3-year survival rates were 17.6% and 0% for surgery and non-surgery, respectively (HR = 3.680, p = 0.001). In M0 subgroup, 2-year survival rate was 35.7% and 0.0% for surgery and non-surgery groups, respectively (HR = 3.98, p = 0.022).The safety of surgery for well-selected ≥ 80-year elderly gastric cancer patients was potentially acceptable and the patients of early or locally advanced diseases could obtain survival benefits by surgery.

This paper focuses on the pair-matching problem of Two-Dimensional Angle-Of-Arrival (2-D AOA) estimation for the L-shaped array. The authors adopt a modified array configuration in which the azimuth and elevation angles can be exploited independently. Moreover, by such configuration, the Cross Correlation Matrix (CCM) is employed to accomplish pairing-matching between estimated parameters which obtained by a subspace approach. Numerical simulations verify the effectiveness and performance of the proposed method.

This paper investigates a two-dimensional angle of arrival (2D AOA) estimation algorithm for the electromagnetic vector sensor (EMVS) array based on Type-2 block component decomposition (BCD) tensor modeling. Such a tensor decomposition method can take full advantage of the multidimensional structural information of electromagnetic signals to accomplish blind estimation for array parameters with higher resolution. However, existing tensor decomposition methods encounter many restrictions in applications of the EMVS array, such as the strict requirement for uniqueness conditions of decomposition, the inability to handle partially-polarized signals, etc. To solve these problems, this paper investigates tensor modeling for partially-polarized signals of an L-shaped EMVS array. The 2D AOA estimation algorithm based on rank- ( L 1 , L 2 , · ) BCD is developed, and the uniqueness condition of decomposition is analyzed. By means of the estimated steering matrix, the proposed algorithm can automatically achieve angle pair-matching. Numerical experiments demonstrate that the present algorithm has the advantages of both accuracy and robustness of parameter estimation. Even under the conditions of lower SNR, small angular separation and limited snapshots, the proposed algorithm still possesses better performance than subspace methods and the canonical polyadic decomposition (CPD) method.

This paper investigates a structured sparse SAR imaging algorithm for point scattering model based on tensor decomposition. Several SAR imaging schemes have been developed by researchers for improving the imaging quality. For a typical SAR target scenario, the scatterers distribution usually has the feature of structured sparsity. Without considering this feature thoroughly, the existing schemes have still certain drawbacks. The classic matching pursuit algorithms can obtain clearer imaging results, but the cost is resulting in an extreme complexity and a huge computation resource consumption. Therefore, this paper put forward a tensor-based SAR imaging algorithm by means of multiway structured sparsity which makes full use of the above geometrical feature of the scatterers distribution. The spotlight SAR observation signal is formulated as a Tucker model considering the Kronecker constraint, and then a sparse reconstruction algorithm is introduced by utilizing the structured sparsity of the scene. The proposed tensor-based SAR imaging model is able to take advantage of the Kronecker information in each mode, which ensures the robustness for the signal reconstruction. Both the algorithm complexity analysis and numerical simulations show that the proposed method requires less computation than the existing sparsity-driven SAR imaging algorithms. The imaging realizations based on the practical measured data also indicate that the proposed algorithm is superior to the reference methods even in the severe noisy environment, under the condition of multiway structured sparsity.

Stomach cancer is among the most commonly occurring malignancies worldwide. It would be beneficial to develop a urine-based assay whereby patients with undiagnosed stomach cancer could be screened and their cancer detected in the earliest stages.A urinary metabonomics method based on ultra-performance liquid chromatography combined with quadruple time-of-flight mass spectrometry was used to analyze urine samples from patients with stomach cancer and healthy controls.Statistical analysis revealed a clear separation of patients and healthy controls using the aforementioned methodology. Some significantly changed metabolites were identified.Use of the metabonomics method in patients with stomach cancer could effectively detect distinct changes in urinary metabolites and had the capacity to detect cancer; therefore, it may be a valuable tool in earlier diagnosis. Furthermore, the detection and identification of altered metabolites in the current study may help elucidate possible mechanisms involved in stomach cancer.

The purpose of this study was to analyze β-catenin and matrix metalloproteinase-2 (MMP-2) expression in non-small cell lung cancer (NSCLC) and to investigate the association between their expression and clinicopathologic characteristics of NSCLC patients. Immunohistochemistry was performed to examine β-catenin and MMP-2 protein expression in 39 resected NSCLC samples and 8 adjacent normal lung tissues. Statistical analysis with SPSS13.0 software was performed to investigate the association between β-catenin and MMP-2 expression and clinicopathologic features of the patients. Expression of cytosolic β-catenin in NSCLC tissue was significantly higher than that in normal tissues (P < 0.001). In addition, cytosolic protein expression of β-catenin in lung squamous cell carcinoma was significantly elevated compared to that in lung adenocarcinoma (P = 0.02). However, cell membrane protein expression of β-catenin in squamous cell carcinoma was lower than that in adenocarcinoma (P = 0.041). Cytosolic MMP-2 protein expression in NSCLC samples was significantly higher than that in normal tissues (P = 0.002). MMP-2 expression in N (1-2) NSCLC patients was significantly increased relative to N (0) patients (P = 0.019). However, statistical analysis showed no correlation between β-catenin and MMP-2 expression in NSCLC samples. Collectively, our results show that cytosolic protein expression of β-catenin in NSCLC samples is increased relative to normal lung tissues. Also, expression of β-catenin is significantly elevated in squamous cell carcinoma compared to that in lung adenocarcinoma subtypes. Additionally, MMP-2 expression in N (1-2) NSCLC tissues is higher than that in N (0) lung tissue. There is no correlation between β-catenin and MMP-2 expression in NSCLC, and our study suggests that evaluation of β-catenin and MMP-2 expression may have potential in diagnosis and progression in patients with NSCLC.

Statins have recently come under evaluation for the treatment of pulmonary arterial hypertension (PAH). The aim of this study was to examine the effects of atorvastatin on the clinical manifestations and expression of p38, p27 and Jab1 using a rat PAH model. Ninety-six male Wistar rats were divided into control (receiving no surgical treatment), vehicle and treatment groups, among which the last two groups underwent left pneumonectomy and were then treated with monocrotaline (MCT, 60 mg/kg). Both control and vehicle groups subsequently received saline, and the treatment group received atorvastatin (20 mg/kg) by stomach catheter. Rats were sacrificed, and mean pulmonary arterial pressure (mPAP) and right ventricle hypertrophy index (RVHI) were measured. The expression of p38, p27, and Jab1 was evaluated by immunohistochemistry and Western blotting. At 28 days, mPAP and RVHI and expression levels of Jab1 and p38 in the vehicle group were significantly higher than those in the treatment and control groups. However, the expression of p27 was lowest in the vehicle group among the three groups. Atorvastatin reduced PAP and RVHI in the rat PAH model, decreased expression of p38 and Jab1 but increased expression of p27.

Local hypothermia induced by intravascular infusion of cold saline solution effectively reduces brain damage in stroke. We further determined the optimal temperature of local hypothermia in our study.Seventy-eight adult male Sprague Dawley rats (260 - 300 g) were randomly divided into 3 groups: group A, ischemia/reperfusion without cold saline infusion (n = 26) (control group); group B, infusion with 20 degrees C saline before reperfusion (n = 26); group C: infusion with 10 degrees C saline before reperfusion (n = 26). In each group, we chose 15 rats for monitoring physical indexes and the temperature of the brain (cortex and striatum) and body (anus), measurement of brain infarction volume, assessment of neurological deficits and the survival rate of reperfusion at 48 hours. Another 8 rats from each group was chosen for examining brain edema, another 3 from each group for histological observation by electron microscopy (EM) and light microscopy (LM) at 48 hours after reperfusion.There was no significant difference among the 3 groups for physical indexes during the examination (F((2, 45)) = 0.577, P = 0.568; F((2, 45)) = 0.42, P = 0.78 for blood pressure and blood gas analysis, respectively). The brain temperature was significantly reduced in the group C compared to the other groups (F((2, 45)) = 37.074, P = 0.000; F((2, 45)) = 32.983, P = 0.000, for cortex and striatum temperature respectively), while the difference in rectal temperature between group A and B or C after reperfusion was not significant (F((2, 45)) = 0.17115, P = 0.637). And the brain infarct volume was significantly reduced in group C (from 40% +/- 10% in group A, 26% +/- 8% in group B, to 12% +/- 6% in group C, F((2, 45)) = 43.465, P = 0.000) with the neurological deficits improving in group C (chi(2) = 27.626, P = 0.000). The survival rate at 48 hours after 10 degrees C and 20 degrees C saline reperfusion was increased by 132.5% and 150%, respectively, as compared to the control group (chi(2) = 10.489, P = 0.005). The extent of the brain edema showed no significant difference (F((2, 21)) = 0.547, P = 0.587) after cold saline infusion compared to the control group. No obvious vascular injury was found by electron or light microscopy in either infusion group.Regional hypothermia with 10 degrees C cold saline infusion can significantly decrease the infarction volume, improve the neurological deficits, and 10 degrees C seems to be the optimal temperature in inducing a cerebral protection effect during stroke. This procedure could be adopted as a further treatment for acute stroke patients.

To investigate the expressions of Urotensin II (UII) protein and mRNA and its receptor (UT) mRNA of medium and small pulmonary arteries of rats with chronic thromboembolic pulmonary hypertension.The Wistar rats were injected thrombi through the jugular vein 2 times in 2 weeks and tranexamic acid was injected peritoneally once daily during the experiment to prevent thrombolysis. The mean pulmonary artery pressure (mPAP) was measured using right cardiac atheterzation. The expressions of UII protein in pulmonary arteries were studied by immunohischemistry with a polycolonal antibody. The expressions of UII mRNA and UT mRNA were detected by in situ hybridization using UII and UT oligonuclear probes. The changes of structures in pulmonary vessle were observed, including relative medial thickness of pulmonary artery (PAMT) and vessle wall area/total vessle area (WA/TA).The mPAP of the 4 weeks to the 12 weeks groups were (19.9 +/- 6.2) mm Hg (1 mm Hg = 0.133 kPa), (23.8 +/- 4.1) mm Hg and (27.4 +/- 5.4) mm Hg, higher than that of the control group (F = 13.75, P0.01, respectively). The PAMT of the 4 weeks to the 12 weeks groups were (42.6 +/- 11.16)%, (47.82 +/- 10.02)% and (53.79 +/- 10.41)%, and WA/TA of the 4 weeks to the 12 weeks groups were (22.75 +/- 6.79)%, (25.32 +/- 4.90)% and (27.05 +/- 7.71)%, both changed significantly as compared to the control group (F = 5.52 and 6.61, P0.01, respectively; P0.05 in 4 weeks group; P0.01 in 8 weeks and 12 weeks groups, respectively). The expressions of UIIprotein, UII mRNA and UT mRNA in the 4 weeks to the 12 weeks groups were obviously higher than the control group (F = 30.39, 30.78 and 14.49, P0.01, respectively), and their expressions were more marked in the small pulmonary arteries than in medium pulmonary arteries. The expressions of UIIprotein, UII mRNA and UT mRNA were positively correlated with mPAP and PAMT. The pulmonary vascular remodeling was time-dependently aggravated after embolism (r: 0.822, 0.866 and 0.846; 0.675, 0.712 and 0.756, P0.01, respectively).The expressions of UII protein, UII mRNA and UT mRNA of pulmonary arteries in the animal models were higher than those in the control group. These dynamic changes of UII mRNA, UIIprotein and UT mRNA may contribute to the development of pulmonary hypertension and vascular remodeling after pulmonary thromboembolism.