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Plasmonic nanoparticles can be employed as a promising integrated platform for lumped optical nanoelements with unprecedentedly high integration capacity and efficient nanoscale ultrafast nonlinear functionality. Further minimizing the size of plasmonic nanoelements will lead to a rich variety of nonlocal optical effects due to the nonlocal nature of electrons in plasmonic materials. In this work, we theoretically investigate the nonlinear chaotic dynamics of the plasmonic core-shell nanoparticle dimer consisting of a nonlocal plasmonic core and a Kerr-type nonlinear shell at nanometer scale. This kind of optical nanoantennae could provide novel switching functionality: tristable, astable multivibrators, and chaos generator. We give a qualitative analysis on the influence of nonlocality and aspect ratio of core-shell nanoparticles on the chaos regime as well as on the nonlinear dynamical processing. It is demonstrated that considering nonlocality is very important in the design of such nonlinear functional photonic nanoelements with ultra-small size. Compared to solid nanoparticles, core-shell nanoparticles provide an additional freedom to adjust their plasmonic property hence tuning the chaotic dynamic regime in the geometric parameter space. This kind of nanoscale nonlinear system could be the candidate for a nonlinear nanophotonic device with a tunable nonlinear dynamical response.

Background: Callosal Angle (CA) and Evans Index (EI) are considered as imaging biomarkers to diagnose normal-pressure hydrocephalus using traditional MR measurement methods. Objective: The current study was aimed to evaluate the differential diagnostic value of CA and EI in the mild cognitive impairment (MCI) and Alzheimer’s disease (AD). Methods: Five-hundred and two subjects were selected from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database, which included 168 Normal Controls (NC), 233 MCI and 101 AD patients. The structural MR images were interactively applied with multiplanar reconstruction to measure the CA and EI. Results: CA presented no significant difference among NC, MCI and AD groups (H value = 3.848, P value = 0.146), and EI demonstrated higher value in MCI and AD groups than that in NC groups (P = 0.000 and 0.001, respectively). MCI group had significant larger EI (0.29±0.04) than (0.27±0.03) NC group in 70-75 years old sub-groups. ROC showed that the area under the curve was 0.704±0.045 for NC-MCI in 70-75 years old groups. The correlation analysis indicated that EI was significantly negatively related to MMSE scores of MCI patients (r = -0.131, P = 0.046). Conclusion: EI might serve as a screening imaging biomarker for MCI in 70-75 years old, and show limited differential value for the diagnosis of AD. CA could present no diagnostic value for MCI and AD in the current study.

In this paper, an inverse problem to identify parameters for the multi-term time fractional partial differential equation with Caputo fractional derivative is considered. The numerical solution of the direct problem is obtained by the modified fractional predictor–corrector method, while the inverse problem is conducted by the modified hybrid Nelder–Mead simplex search and particle swarm optimization (MH-NMSS–PSO) algorithm, which is expanded to estimate parameters for fractional differential equations. To verify the efficiency and accuracy of the proposed methods, three numerical examples with experimental data are conducted. Furthermore, in order to improve the practical significance of the research on inverse problems, the predictive value of parameter estimation is also testified. This paper provides effective numerical methods for parameter estimation in practical applications involving multi-term time fractional constitutive equations.

Most existing research on applying the finite element method to discretize space fractional operators is studied on regular domains using either uniform structured triangular meshes, or quadrilateral meshes. Since many practical problems involve irregular convex domains, such as the human brain or heart, which are difficult to partition well with a structured mesh, the existing finite element method using the structured mesh is less efficient. Research on the finite element method using a completely unstructured mesh on an irregular domain is of great significance. In this paper, a novel unstructured mesh finite element method is developed for solving the time-space fractional wave equation on a two-dimensional irregular convex domain. The novel unstructured mesh Galerkin finite element method is used to discretize in space and the Crank-Nicolson scheme is used to discretize the Caputo time fractional derivative. The implementation of the unstructured mesh Crank-Nicolson Galerkin method (CNGM) is detailed and the stability and convergence of the numerical scheme are analysed. Numerical examples are presented to verify the theoretical analysis. To highlight the ability of the proposed unstructured mesh Galerkin finite element method, a comparison of the unstructured mesh with the structured mesh in the implementation of the numerical scheme is conducted. The proposed numerical method using an unstructured mesh is shown to be more effective and feasible for practical applications involving irregular convex domains.

The magnetic resonance imaging findings of multicystic encephalomalacia are featured by bilateral frontal large cystic lesion with corpus callosum involvement,evident heterogeneous enhancement of the lesion margin,ring hyperintensity on diffusion weighted imaging,and high choline peak and low N-acetylaspartate peak of the enhanced lesion margin on magnetic resonance spectroscopy.This article reports a case of multicystic encephalomalacia.

Background: Quantitative susceptibility mapping (QSM) technique had been used to measure the magnetic susceptibility of brain tissue in clinical practice. However, QSM presented echo-time (TE) dependence, and an appropriate number of echo-times (nTEs) for QSM became more important to obtain the reliable susceptibility value. Objective: The aim of the study was to explore the optimal nTEs for quantitative susceptibility mapping (QSM) measurements of basal ganglia nuclei in the healthy brain. Methods: 3D multi-echo enhanced gradient recalled echo T2 star weighted angiography (ESWAN) sequence was acquired on a 3.0T MR scanner for QSM analysis. Regions of interests (ROIs) were drawn along the margin of the head of the caudate nucleus (HCN), putamen (Pu) and globus pallidus (GP). The mean susceptibility value and standard deviation of the ROIs were derived from the pixels within each region. Results: CV analysis demonstrated that TE6, TE8 and TE14 ESWAN sequences presented consistent lower CV value (< 1) for QSM measure of HCN, Pu and GP. ANOVA identified that susceptibility value showed no significant difference between TE6 and TE8 in HCN, Pu and GP (P < 0.05). ICC analysis demonstrated that the susceptibility value of TE6-TE8 had the highest ICC value as compared with TE6-TE14 and TE8-TE14 in HCN, Pu and GP. Combined with the timeefficiency of MRI scanning, TE6 sequence could not only provide the reliable QSM measurement but also short imaging time. Conclusions: The current study identified that the optimal nTEs of ESWAN were 6 TEs (2.9ms ~ 80.9ms) for QSM measurement of basal ganglia nuclei in the healthy brain.

Objective To investigate the difference in texture features on diffusion weighted imaging (DWI) images between breast benign and malignant tumors.Methods Patients including 56 with mass-like breast cancer, 16 with breast fibroadenoma, and 4 with intraductal papilloma of breast treated in the Hainan Hospital of Chinese PLA General Hospital were retrospectively enrolled in this study, and allocated to the benign group (20 patients) and the malignant group (56 patients) according to the post-surgically pathological results. Texture analysis was performed on axial DWI images, and five characteristic parameters including Angular Second Moment (ASM), Contrast, Correlation, Inverse Difference Moment (IDM), and Entropy were calculated. Independent sample t-test and Mann-Whitney U test were performed for intergroup comparison. Regression model was established by using Binary Logistic regression analysis, and receiver operating characteristic curve (ROC) analysis was carried out to evaluate the diagnostic efficiency.Results The texture features ASM, Contrast, Correlation and Entropy showed significant differences between the benign and malignant breast tumor groups (PASM=0.014, Pcontrast=0.019, Pcorrelation=0.010, Pentropy=0.007). The area under the ROC curve was 0.685, 0.681, 0.754, and 0.683 respectively for the positive texture variables mentioned above, and that for the combined variables (ASM, Contrast, and Entropy) was 0.802 in the model of Logistic regression. Binary Logistic regression analysis demonstrated that ASM, Contrast and Entropy were considered as the specific imaging variables for the differential diagnosis of breast benign and malignant tumors.Conclusions The texture analysis of DWI may be a simple and effective tool in the differential diagnosis between breast benign and malignant tumors.

Over the past 30 years, China’s urbanization has strongly supported the rapid growth and sustained transformation of economy; it has also led to a continuous increase in atmospheric environmental stress. A deep understanding of the coupling relationship between urbanization and air quality is essential for evaluating the quality of urbanization and long term sustainability. We first constructed a set of indexes to evaluate the extent of urbanization, and then used the global principal component analysis, harmony degree model, as well as the coupling coordination degree model and Geographic Information System (GIS) to explore the coupling relationship between urbanization and air quality in Shandong Province from 2014 to 2017. The results show that: (1) in 2014, cities with a high coupling coordination degree (D > 0.7) between urbanization and air quality index (AQI) as well as pollutants were mainly distributed in coastal regions of Shandong Province. The coupling relationships between urbanization and AQI and PM2.5 in part of central Shandong were basically uncoordinated (0.3

Genome-wide association studies (GWASs) have identified several risk loci for coronary artery calcification. Four single-nucleotide polymorphisms (SNPs, rs1537370, rs1333049, rs2026458 and rs9349379) were associated with coronary artery calcification with P values less than 5 × 10 −8 in GWASs. It is unclear if these associations exist in other vascular beds. Thus, we evaluated the impacts of these four SNPs on carotid artery and aortic arch calcification in this study. Computed tomography was applied to quantify the calcification of carotid artery and aortic arch. 860 patients with stroke completed calcification quantification and genotype testing were included in data analysis. Each SNP was evaluated for the association with carotid artery calcification, and with aortic arch calcification using generalized linear model. Among the four tested SNPs, rs2026458 was associated with calcification in both carotid artery (β = 0.31, 95% confidence interval [CI] 0.10–0.52, P = 0.003) and aortic arch (β = 0.32, 95% CI 0.10–0.54, P = 0.004), while rs1333049 was only associated with carotid artery calcification (β = 0.28, 95% CI 0.06–0.50, P = 0.011). In gender-stratified analyses, rs2026458 had significant impacts on carotid artery ( P = 0.003) and aortic arch calcification ( P = 0.008) in male, but not in female patients; while rs1537370 was significantly associated with carotid artery calcification in female ( P = 0.013), but not in male patients. In conclusion, SNPs associated with coronary artery calcification may also increase the risk of calcification in other arteries such as carotid artery and aortic arch.

In the present study, an inverse problem to estimate parameters in the Zener model of viscoelasticity based on the generalized fractional element (GFE) network is studied. The Bayesian method is proposed to obtain the optimal estimation of the viscoelastic parameters. Three examples are performed to certify the validity of the method. All numerical results lead to an excellent fitting between the calculative results and experimental data. It is shown that the Bayesian method is feasible in the inverse problem of parameter estimation for the fractional constitutive equation, and the GFE network Zener model is efficient in the modeling of the viscoelastic behavior.

Hybrid App is mainly realized by calling each other by JavaScript (JS) and Native, so it implements the mechanism of ‘one development, multi operation’, so it can be called the real cross-platform development. The most striking difference of Hypertext Markup Language 5 (HTML5) and JavaScript from WebApp is that they call the bottom function encapsulated by NativeApp. Hybrid App is characterized by cross-platform as it uses the browser as engine; it has the similar development costs while the far more development efficiency compared with NativeApp. This paper used HybridApp development mode to develop by taking Android platform as the example; with the help of online map service and query interface of MAP WORLD, the foreground show and map interaction were implemented by Openlayers map frame; users' information data was managed by Sqlite embedded database; the mobile devices information were acquired by calling each other by PhonedGap frame and mobile devices; functions like friends-positioning, enquiry POI and north arrow, etc., were realized in this App. This paper also elaborated the prospects and application value of Hybrid App in future mobile development.

Objective To investigate the difference of texture on conventional T2-weighted image (T2WI) between hepatic cyst and hepatic hemangioma. Methods All the subjects included 156 patients with hepatic cyst [A group:100 cases with equi or low signal on diffusion weighted imaging (DWI);B group:56 cases with high signal on DWI] and 100 patients with hemangioma (C group). Conventional magnetic resonance imaging T2WI,DWI and dynamic contrast enhancement were performed on all the patients,and the texture analysis was applied with the images of T2WI,and the texture parameters included angular second moment,contrast,correlation,inverse difference moment,and entropy. Independent sample t-test and Aspin-Welch test were performed for the comparisons among groups. Results All the texture parameters showed significant difference among groups [(A+B) group vs. C group:ρ

Background and purpose S100B and its scavenger, soluble receptor for advanced glycation end products (sRAGE), participate in various acute and chronic brain disorders. However, their impact on hemorrhage-prone small vessel disease represented by cerebral microbleeds (CMBs) is unclear. The purpose of this study was to investigate the relationship of CMBs with plasma S100B and sRAGE. Methods A cohort of 147 consecutive patients with first-ever acute lacunar stroke was prospectively enrolled. We collected demographic, clinical, and laboratory data, including plasma levels of S100B and sRAGE, and presence and number of CMBs using susceptibility-weighted imaging (SWI). Associations between plasma S100B, sRAGE levels and the presence, number, and location of CMBs were determined. Results CMBs were present in 58 patients (39.5%). Each 1SD-increase in S100B and sRAGE levels was significantly associated with presence of CMBs (adjusted odds ratio [OR], 3.06; 95% confidence interval [CI], 1.81–5.17 and adjusted OR, 0.29; 95% CI, 0.16–0.53; respectively) and number of CMBs (adjusted relative risk [RR], 4.07; 95% CI, 3.60–5.65 for S100B and RR 0.34; 95% CI, 0.25–0.46 for sRAGE). When stratified by location, plasma S100B and sRAGE levels were similarly associated with presence of deep CMBs (adjusted OR, 3.65; 95% CI, 1.99–6.69 and adjusted OR, 0.23; 95% CI, 0.12–0.46; respectively), but not with strictly lobar CMBs. Conclusions Higher levels of S100B and lower levels of sRAGE are independently associated with presence and number of CMBs in patients with first-ever acute lacunar stroke, particularly in those with deep CMBs.

This paper proposes a framework of quantitative analysis of urban form based on GIS and reports an empirical study of Shanghai city to investigate the evolutional characteristics of urban form. By using ERDAS IMAGINE and GIS, the spatial form characteristics of Shanghai has been extracted based on a series of Landsat TM and ETM imagery over the period from 1982 to 2008; by combining fractal dimension theory, compactness ratio theory, space syntax theory etc with the spatial analysis technology of GIS, the urban form characteristics of Shanghai has been analyzed quantitatively in terms of urban external shape, urban internal structure, urban population size and urban transportation. Practice has proved that the combination of GIS with the theories of fractal dimension and space syntax etc can not only help to learn the principals of urban nature but also can explore the intrinsic interactive mechanism of geographic entities by deeply mining the spatial data.

This paper analyzes the basic principle of the air-jet loom electronic weft-feeder and designs a high speed electronic weft-feeder control system based on BLDC Motor and introduces the implementation of the hardware and software in detail. Laboratory platform and air-jet loom debugging show that the designed system realizes three functions, the weft yarn storage, fixed length and yarn tension balance, the highest weft insertion rate of the system reaches 2000m / min, which meet the design requirements.

Stroke is one of the leading causes of death and long-term disability worldwide. Mitochondrial DNA (mtDNA) is a potential contributor for the sex differences of ischemic stroke heritability. Although mtDNA haplogroups were associated with stroke onset, their impacts on stroke outcomes remain unclear. This study aimed to evaluate the impacts of mtDNA haplogroups on short-term outcomes of neurological functions in patients with ischemic stroke. A total of 303 patients were included and their clinical data and mtDNA sequences were analyzed. Based on the changes between baseline and 14-day follow-up stroke severity, our results showed that haplogroup N9 was an independent protective factor against neurological worsening in acute ischemic stroke patients. These findings supported that mtDNA variants play a role in post-stroke neurological recovery, thus providing evidences for future pharmacological intervention in mitochondrial function.

Rapid urbanisation has resulted in the change of urban forms as well as increased consumption of various urban resources. This paper reports an empirical study of China’s Shanghai municipality to investigate the relationship between urban form and the efficiency usage of urban resources. Based on a series of Landsat imagery over the period from 1982 to 2008, the changing characteristics of the urban spatial forms in Shanghai were measured in GIS. Urban resources efficiency was measured through Data Envelopment Analysis (DEA) approach. By correlating the urban form and resource efficiency indicators through a regression analysis, the results show that the changes of urban resource efficiency are closely related to changes of urban forms. In general, the instability and complexity of the external form of the city reduces the urban resources efficiency. Moreover, high population density conduces to lower urban resources efficiency. In addition, the road network density and the spatial accessibility through the road network impact significantly the improvement of urban resources efficiency; besides, the compactness of urban external form does not have much influence on urban resources efficiency according to this study.

Background and Purpose— The relationship between chronic kidney disease and cerebral small vessel disease (cSVD), especially enlarged perivascular spaces (EPVS), has not been fully understood. This study aimed to investigate the association of chronic kidney disease and EPVS, as well as the total burden of cSVD on magnetic resonance imaging, expressed by the simultaneous presence of multiple markers of cSVD, among patients with first-ever lacunar stroke. Methods— Four hundred and thirteen consecutive patients were prospectively enrolled. Centrum semiovale and basal ganglia EPVS on T2-weighted magnetic resonance imaging, as well as other imaging markers of cSVD, including lacune, white matter lesions, and cerebral microbleeds, were rated using validated scales. Chronic kidney disease was defined as either reduced estimated glomerular filtration rate or the presence of proteinuria. Results— After adjustments for potential confounders by logistic regression, proteinuria and impaired estimated glomerular filtration rate were correlated with the severity of EPVS in both centrum semiovale (odds ratio [OR] 2.59; 95% confidence interval [CI] 1.19–5.64 and OR 2.37; 95% CI 1.19–4.73) and basal ganglia (OR 5.12; 95% CI 2.70–12.10 and OR 4.17; 95% CI 2.08–8.37). A similar association was also found between proteinuria and low estimated glomerular filtration rate levels and the comprehensive cSVD burden (OR 2.13; 95% CI 1.10–4.14 and OR 5.59; 95% CI 2.58–12.08). Conclusions— Proteinuria and impaired estimated glomerular filtration rate are associated with increasing EPVS severity and, furthermore, accumulated magnetic resonance imaging burden of cSVD in patients with first-ever acute lacunar stroke.

In this paper, the fractional Schrodinger equation is studied. The Bayesian method is put forward to estimate some relevant parameters of the equation. Results show that the estimated values can fit well with the exact solution. The varying initial values and maximum iterations have little effect on the estimated results. It indicates that the Bayesian method is efficient for the multi-parameter estimation for the fractional Schrodinger equation. This method can also be used to estimate parameters for the fractional Schrodinger equation in other potential field.