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The coverage, thickness, and crystallinity of ZnIn2S4 (ZIS) shells on SiO2 core nanoparticles (SiO2@ZIS) were systematically investigated using microwave-assisted solvothermal methods aided by the addition of acid in ethanolic medium. The surface modification of the SiO2 cores with (3-mercaptopropyl)trimethoxysilane was found to be critical to generate a homogeneous coverage of ZnIn2S4. The SiO2@ZIS core-shell nanoparticles exhibited the best coverage but poor crystallinity when synthesized in pure ethanol, whereas best crystallinity but poor coverage was observed when synthesized in an aqueous solution. The addition of selected amounts of acid (HCl) led to improved crystallinity in the ethanolic medium. The thickness of the ZIS shell could be controlled in an ethanolic solution by judiciously varying the amounts of acid and the concentration of the ZIS precursor. Increasing the concentration of the ZIS precursor to twice the standard concentration in ethanolic solution with the addition of 100 μL of HCl afforded better crystallinity, homogeneous coverage, and optimal photocatalytic hydrogen production.

Novel structures of type II, III, and IV linear-phase finite impulse response (FIR) systems are proposed. It is constituted of a linear combination of basic sub-filters, called cardinal filters , with weighting coefficients equal to the derivatives of the system amplitude response at a prescribed frequency. Since the cardinal filters can be synthesized via recursive closed-form expressions, regardless of the desired system amplitude response, the proposed structure provides a universal design for arbitrary derivative-constrained linear-phase FIR filters. Design examples of maximally flat filters show that further improvement by combining derivative constraints with the least squared error optimization technique can be obtained.

The coverage, thickness, and crystallinity of ZnIn

A challenge in designing an optimal parallel distributed detection system is its exponentially increasing number of possible combinations of local quantization rules with respect to n local sensors...

In this paper, a general structure of linear-phase finite impulse response filters, whose frequency responses satisfy given derivative constraints imposed upon an arbitrary frequency, is proposed. It is comprised of a linear combination of parallelly connected subfilters, called the cardinal filters , with weighted coefficients being the successive derivatives of the desired frequency response at the constrained frequency. An advantage of such a cardinal filters design is that only the weighted coefficients are relevant to the desired frequency response but not the cardinal filters; hence, a dynamic adjustment of the filter system becomes feasible. The key to derive the coefficients of cardinal filters is the determination of the power series expansion of certain trigonometric-related functions. By showing the elaborately chosen trigonometric-related functions satisfy specific differential equations, recursive formulas for the coefficients of cardinal filters are subsequently established, which make efficient their computations. At last, a simple enhancement of the cardinal filters design by incorporating the mean square error minimization is presented through examples.

It is known that in addition to spectrum sparsity, spatial sparsity can also be used to further enhance spectral utilization in cognitive radio systems. To achieve that, secondary users (SUs) must know the locations and signal strength distributions (SSDs) of primary users' base stations (PUBSs). Recently, a group sparse total least squares method was developed to cooperatively sense the PUBSs' signal strength and estimate their locations. It approximates PUBSs' power decay with a path loss model (PLM), assumes PUBSs' locations on some grid points, and then accomplishes the estimation tasks. However, the parameters of the PLM have to be known in advance, and the accuracy of the location estimation is bounded by the resolution of the grid points, which limit its practical applications. In this paper, we propose a sparse Bayesian learning method to solve the problems. We use a Laplacian function to model the power decay of a PUBS and then derive learning rules to estimate corresponding parameters. The distinct features of the proposed method are that most parameters are adaptively estimated, and little prior information is needed. To further enhance the performance, we incorporate source number detection methods in the proposed algorithm such that the number of the PUBSs can be precisely detected, facilitating the estimation of PUBSs' locations and SSDs. Moreover, the proposed algorithm is modified into a recursive mode to adapt to SUs' mobility and time-variant observations. Simulations show that the proposed algorithm has good performance, even when the spatial measurement rate is low.

In this paper, a general structure of type-III FIR filters with derivative constraints is proposed. It consists of a linear combinations of basic sub-filters, called cardinal filters, with weighting coefficients equal to derivatives of the target frequency response at ω = 0. Closed-form expressions for these cardinal filters are derived and their filter coefficients are shown to have a simple recursive relation. Numerical experiments confirm that the proposed design is much more numerically stable than the solution obtained by solving the derivative constraints.

Background The present subanalysis of the Study of Once Daily Levemir (SOLVE) study was to evaluate the safety and efficacy of once-daily insulin detemir as add-on to oral antidiabetic drugs (OADs) in Chinese type 2 diabetes patients according to body mass index in a real-life setting. Methods In all, 3272 eligible patients who were treated with diet, exercise, and one or more OAD were prescribed once-daily insulin detemir by their physician according to routine clinical practice and were followed-up for 24 weeks. The incidence of serious adverse reactions (SADRs), including major hypoglycemia, was the primary endpoint. Subanalyses were performed on patients in the following BMI groups: normal weight (BMI

This paper presents the closed-form designs of an infinite-impulse-response (IIR) Hilbert transformer with an integer delay. The maximally flat criterion is applied at the midband frequency π/2. These designs are further categorized into eight types according to the filter orders and the delay values being even or odd. Their coefficients can be explicitly solved in closed form. A recursive relation also exists, facilitating the computation of these coefficients. Moreover, under the suggested relations and formula for the design parameters based on the Enestrom-Kakeya theorem, we can obtain a satisfactory stable IIR Hilbert transformer.

In this paper, we propose a fractional delay filter, an integer-order differintegrator, a fractional Hilbert transformer, and a fractional differintegrator. Through the time-domain analysis on the desired input and output signals of a linear time-invariant system, we derive a set of linear equations, which can be solved to obtain the coefficients of the desired filter. We also show that the difference between the desired output signal and the actual output of the system can be represented as the convolution of the derivative of the input signal and the Peano kernel.

Objective The aim of this study was to assess the levels of serum lipid and awareness, treatment, and control of dyslipidemia in type 2 diabetes mellitus (T2DM) patients from top-ranked endocrinology clinics in large cities of China. Materials and Methods A cross-sectional study in a representative sample of 4807 Chinese adults 40 to 75 years of age was conducted during 2010 to 2011 at 20 endocrinology clinics in top-ranked hospitals covering most of the major cities of China. Serum lipid levels were measured, and treatment of dyslipidemia was recorded and assessed. Results In the present study, the prevalence of dyslipidemia was 67.1% in T2DM subjects. Among those with dyslipidemia, the proportion of awareness and treatment was 68.7% and 55.9%. Among participants with lipid-lowering therapy, 686 subjects achieved the low-density lipoprotein cholesterol (LDL-C) control less than 2.60 mmol/L, with the rate being 39.4%. In those patients with previous cardiovascular disease, the percentage of participants who achieved LDL-C goal (1.80 mmol/L) was 15.3%. Conclusion The prevalence of dyslipidemia is high, and the awareness, treatment, and control of dyslipidemia are relatively low in Chinese T2DM patients. This calls for the awareness and intervention of dyslipidemia in these patients.

Eight types of maximally flat finite impulse response (FIR) fractional delay filters are proposed. They are designed by separately approximating the real part and the imaginary part of the frequency response. Among these eight types of filters, two of them are equivalent to the existing design results in the open literature. Therefore, a more general closed-form design of the maximally flat FIR fractional delay filters is described in this letter, and some design examples of FIR fractional delay filters will be illustrated

In this letter, we propose a novel all-pass (AP) fractional delay filter whose denominator polynomial is obtained by truncating the power series of a certain function. This function is derived from the frequency response of the denominator whose magnitude response is related to the desired phase response through the Hilbert transform since the denominator of a stable AP filter is of minimum phase. The target function and corresponding power series are calculated analytically and expressed in closed form. The closed-form expressions facilitate the analysis of stability. According to the properties for the coefficients of the denominator polynomial, we show that the proposed AP filter is stable for positive delay. Numerical examples indicate that the phase delays of the proposed filters are flat around DC.

An effective eigenfilter approach is presented to design special classes of infinite-impulse response (IIR) filters with time- and frequency-domain constraints is presented. By minimizing a quadratic measure of the error in the passband and stopband, an eigenvector of an appropriate real symmetric and positive-definite matrix is computed to get the filter coefficients. Several IIR filters such as notch filters, Nyquist filters and partial response filters can be easily designed by this approach. Some numerical design examples are illustrated to show the effectiveness of this approach.

We propose a method of designing equiripple linear-phase FIR filters with linear constraint by using the Remez exchange algorithm. A novel technique is derived to convert a linearly constrained problem into an equivalent unconstrained one. We proposed a technique to modify the original desired frequency response so that the original linear constraint can be reduced to a simpler one (the null constraint) for the new target frequency response. The filter with null constraint can be designed without constraint by transformation of the original basis functions. The transformation is represented by a basis for the null space of the constraint. In this paper, we show that the transformed basis set also forms a Tchebycheff set. This fact indicates the proposed design is optimal in the Tchebycheff sense. The optimal filter is deigned by the Remez method according to the new target frequency response in transformed basis. Design examples suggest that the proposed algorithm converges fast and stably.

In this paper, novel closed-form designs of the FIR Hilbert transformers, maximally flat digital differentiators and fractional delayers are proposed. The transfer functions of these filters are analytically obtained by expanding some suitable functions into power series. Efficient implementations can be derived from the resultant transfer functions. The weighting coefficients and the building blocks of these filters are explicitly expressed in closed form. The proposed filter structures are more robust to the coefficient quantization than the direct form.

Recently, the classical Hilbert transformer is generalized into the fractional Hilbert transformer which could be implemented optically. This modification of the Hilbert transform adds an additional degree of freedom on the Hilbert transformer and improves the performance of the transform. In this paper, the design of FIR filters fractional Hilbert transformer is proposed. The FIR filters are designed in the maximally flat sense. The impulse responses of the filters are uniquely solved and expressed in simple analytic forms. The impulse responses can be exactly expressed as fixed point binary values. The resulting frequency responses approximate the ideal one very well in the middle-frequency band. Efficient hardware realization structures are obtained based on the symmetric properties of the impulse responses. Several design examples with various transform parameters and various filter orders are presented. Some examples of 1-D/2-D edge detection are given. The examples show that the proposed FIR filter can enhance the selected edges very efficiently.

In this paper, we propose a design of two-dimensional (2-D) linear-phase, diamond-shaped (DS) finite impulse response (FIR) filters by using Bernstein polynomials. Although the one-dimensional (1-D) FIR filter designed by the Bernstein polynomials has been well investigated, this approach has not been broadly applied to 2-D filter design yet. We present a novel method of designing the 2-D FIR DS filter. In order to be approximated by a 2-D Bernstein polynomial, the 2-D symmetrical frequency response is transformed into a new domain. The key observation is that the region of support of the transformed frequency response is not diamond-shaped. The boundary of the new region of support represents an ellipse, a circle, or a line, and is analytically derived. The resultant magnitude responses are flat in the passband and stopband.

In this paper, a new design of fractional sample delay filter is presented. This method is based on the Stancu polynomial, which possesses an extra parameter /spl alpha/. Under special choice of this parameter, the results obtained are identical to previous ones based on Lagrange interpolation formula. Much more flatness of group-delay response can be achieved at the sacrifice of the filter magnitude response. Thus, this method provides designers with more flexibility for trading between these two performance criteria.

In this paper, we propose a novel structure of linear-phase type-I FIR filters. The structure consists of a linear combination of some basic filters, called the cardinal filters. The weighting coefficients are exactly the derivatives of the amplitude response at ω = 0. We solve a closed-form recurrence relationship between the filter coefficients. Implementation of the cardinal filters is discussed.

To characterize the baseline status of Chinese diabetic patients based on data derived from Chinese cohort from SOLVE(TM) study.Patients with type 2 diabetes initiating basal insulin detemir at the decision of the physician were eligible for the study. Data on demographics, medical history, glycemic profile and treatment regimen at baseline were collected by physicians.A total of 3272 patients [female 42%, male 58%, mean age (56.2 ± 10.8) years] were included in the study. Their BMI was (25.3 ± 3.3) kg/m(2). The duration of diabetes was 4.0 (0.1 - 27.0) years, and the duration of treatment with oral antidiabetic drugs (OADs) was 3.0 (0.0 - 20.2) years. The proportions of subjects with diabetic macro- and micro-vascular complications were 15.8% (515 cases) and 27.1% (866 cases), respectively. The hemoglobin A1c (HbA1c) at baseline was (8.33 ± 1.70)%, and the fasting blood glucose (FPG) was (9.5 ± 2.6) mmol/L.A large proportion of patients with type 2 diabetes remain in poor glycemic control, and the prevalence of diabetic complications is high, which requires optimal therapeutic strategy for the patients with suboptimal glycemic control.

How to manufacture a low-cost digital still camera (DSC) that can meanwhile provide a good image quality is always an engineering challenge. For this purpose, the color filter array (CFA) is perhaps the most commonly used structure for modern DSCs. However, since most of the color information is filtered out, a good interpolation process is required to retrieve the original image. Many interpolation methods have thus been proposed. In this work, we propose to perform the edge-preserving signal correlation based (EP-SCB) interpolation [1] as a second pass to those images restored from some other existing interpolation methods such as local polynomial approximation intersection of confidence intervals (LPA-ICI) rule [2]. Experiments show that most of the images' PSNRs can be improved by the second pass. The simplicity of the EP-SCB hence makes it a suitable candidate as an enhancement option for DSCs techniques.

To examine the distribution patterns of pathogens isolated from the patients with diabetic foot ulcers and explore the risk factors for infections of methicillin-resistant S. aureus (MRSA) or methicillin-resistant S. epidermidis (MRSE).A total of 388 diabetic-foot patients hospitalized at Tianjin Metabolic Diseases Hospital between January 2008 and June 2010 were recruited. The distribution profiles of pathogens isolated from diabetic foot ulcers were summarized. The patients with S. aureus infections were divided into MRSA and MSSA groups while those with S. epidermidis infections into MRSE and MSSE groups. The clinical features of these patients were compared between all groups. Logistic regression was employed to identify the risk factors for the MRSA/MRSE infections.A total of 362 pathogens were isolated from them. And the Gram-positive bacteria were the most predominant (57.2%, 207/362), followed by Gram-negative bacilli (39.2%, 142/362) and true fungi (3.6%, 13/362). The three most frequently isolated pathogens were S. aureus (27.1%), S. epidermidis (18.8%) and Pseudomonas aeruginosa (15.5%). Statistically significant differences existed in antibiotic usage in 6 months prior to hospitalization, course of ulcer, ulcer size, deep ulcer, osteomyelitis, hypertension, anemia, hypoproteinemia and erythrocyte sedimentation rate between the patients infected with MRSA and MSSA (P0.05). The MRSE infection was correlated with recurrent ulcer, osteomyelitis, hypoproteinemia, HbA1c and lower total serum protein (P0.05). Multiple Logistic regression analysis revealed that antibiotic usage in 6 months prior to hospitalization, long course of ulcer, osteomyelitis, hypertension and hypoproteinemia were risk factors for the MRSA infection. And HbA1c was a risk factor for the MRSE infection.In the present study, the Gram-positive cocci are the main pathogens isolated from diabetic foot ulcers. And S. aureus and S. epidermidis are the most frequently isolated pathogens. Antibiotic usage in 6 months prior to hospitalization, long course of ulcer, osteomyelitis, hypertension and hypoproteinemia are risk factors for the MRSA infection. And HbA1c is a risk factor for the MRSE infection.

In this paper, a classified-based post-compensation algorithm for Color Filter Array (CFA) demosaicing is proposed. This technique can be used for improving the image quality of the interpolated results obtained by other CFA images. First, each pixel is classified according to its neighborhood texture variance and angle. Then, different Least-Mean-Square (LMS) filters are trained to adopt for dealing pixels of various characteristics. As documented in the experimental results, the proposed scheme can substantially boost the image quality; in addition, a better visual perceptual can be obtained. Notably, the proposed method can be considered as effective post-compensation by applying for any former schemes to yield an even better image quality.