Deployment Optimization Method of Multistatic Radar for Constructing Circular Barrier Coverage.

To construct circular barrier coverage (CBC) with multistatic radars, a deployment optimization method based on equipartition strategy is proposed in this paper. In the method, the whole circular area is divided into several sub-circles with equal width, and each sub-circle is blanketed by a sub-CBC that is built based on the multistatic radar deployment patterns. To determine the optimal deployment patterns for each sub-CBC, the optimization conditions are firstly studied. Then, to optimize the deployment of the whole circular area, a model based on minimum deployment cost is proposed, and the proposed model is divided into two sub-models to solve the optimization issue. In the inner model, it is assumed that the width of a sub-circle is given. Based on the optimization conditions of the deployment pattern, integer linear programming (ILP) and exhaustive method (EM) are jointly adopted to determine the types and numbers of deployment patterns. Moreover, a modified formula is introduced to calculate the maximum valid number of receivers in a pattern, thus narrowing the search scope of the EM. In the outer model, the width of a sub-circle is assumed to be a variable, and the EM is adopted to determine the minimum total deployment cost and the optimal deployment patterns on each sub-circle. Moreover, the improved formula is exploited to determine the range of width for a sub-circle barrier and reduce the search scope of the EM. Finally, simulations are conducted in different conditions to verify the effectiveness of the proposed method. The simulation results indicate that the proposed method can spend less deployment cost and deploy fewer transmitters than the state-of-the-artwork.

Stability and sedimentation of silver nanoparticles in the presence of monovalent, divalent and trivalent electrolyte solutions.

The present study seeks to elucidate the effect of different electrolytes on the stability of citrate-coated silver nanoparticles synthesized by the reduction of the Ag(NH3)(2)(+) complex via Tollens' method. Time-resolved dynamic light scattering technique was used to measure the aggregation behavior of the nanoparticles over a range of electrolyte (NaCl, CaCl2, and AlCl3) concentrations. From the aggregation kinetic data, the critical coagulation concentration values were calculated as 0.11, 1.7 × 10⁻³, and 5.06 × 10⁻6 M for NaCl, CaCl2, and AlCl3, respectively. Supernatant of the nanoparticle suspension in presence of the three electrolytes was collected and measured using inductively coupled plasma mass spectrometry to quantify the sedimentation. It was found that the silver nanoparticle aggregates settled rapidly in the slow aggregation and fast aggregation regimes. Their sedimentation followed a nanoparticle size-dependent manner.

Effect of different water conditions on dissolution of nanosilver.

This study evaluates the time-dependent dissolution of nanosilver (nAg) in common electrolytes and natural waters. nAg was synthesized via Tollens' method using sodium citrate as stabilizer; its morphology, UV-Vis spectrum, and particle size were characterized. The dissolved silver was monitored over time using filtration, centrifugation, and inductively coupled plasma atomic emission spectroscopy (ICP-AES). Our results indicated that nanoparticle aggregation, Cl(-) presence, and natural organic compounds could affect the dissolution behavior of nAg. The dissolution of nAg was highly dependent on Cl(-) concentration. Excessive Cl(-) enhanced nanoparticle dissolution, whereas natural organic compound inhibited the dissolution. The dissolution data fitted well with the first-order kinetic model, and the dissolution rate coefficients were calculated using the first-order equation. This study showed the dissolution of nAg under various water conditions. The obtained results may be helpful in predicting nAg behavior in relevant environmental aquatic systems.

Measurement Properties of the Simplified Chinese Version of the Lumbar Spine Instability Questionnaire for Patients With Low Back Pain in Mainland China.

STUDY DESIGN: A prospective study. OBJECTIVE: To develop a simplified Chinese version of Lumbar Spine Instability Questionnaire (SC-LSIQ) and test its measurement properties. SUMMARY OF BACKGROUND DATA: The LSIQ has been translated into several languages. Different versions of LSIQ have proved good reliability and validity in evaluating patients with low back pain. However, there is no simplified Chinese version of LSIQ (SC-LSIQ). MATERIALS AND METHODS: The SC-LSIQ has been translated into a simplified Chinese version according to a standard procedure. A total of 155 patients with low back pain completed the SC-LSIQ along with Oswestry Disability Index, Roland-Morris disability questionnaire, Tampa Scale for Kinesiophobia, and visual analogue scale (VAS). The internal consistency, test-retest reliability, and validity of SC-LSIQ were then calculated to evaluate the measurement properties of SC-LSIQ. RESULTS: The results of SC-LSIQ demonstrated that there was no ceiling or floor effect detected. The Cronbach α coefficient of 0.911 determined a well internal consistency. The intraclass correlation coefficient (0.98) presented an excellent reliability of SC-LSIQ. The Pearson correlation coefficient (r) showed that the SC-LSIQ was excellent correlated to Oswestry Disability Index (r=0.809), Roland-Morris disability questionnaire (r=0.870), and Tampa Scale for Kinesiophobia (r=0.945,). Furthermore, it moderately correlated to visual analogue scale (r=0.586). CONCLUSION: The SC-LSIQ features good internal consistency, reliability, and validity for evaluating Chinese patients with LBP. Results suggest that the SC-LSIQ can be appropriately applied to patients with LBP in routine clinical practice.

Multifunctional necklace-like Cu@cross-linked poly(vinyl alcohol) microcables with fluorescent property and their manipulation by an external magnet.

Unique magnetite-nanoparticles-attached necklace-like Cu@cross-linked poly(vinyl alcohol) (PVA) microcables with multi-functionalities can be synthesized by in situ loading the magnetite nanoparticles in the network structure of a cross-linked PVA sheath using a modified polyol method; the superparamagnetic and green fluorescent properties of the cables enable this type of magnetic functionalized microcables to be manipulated and detected easily for device fabrication.

Persicariajucunda var. rotunda (Polygonaceae, Persicarieae), a distinct distylous taxa raised to specific rank.

Persicariajucunda(Meisn.)Migovar.rotunda (Z.Z.Zhou & Q.Y.Sun) Bo Li was originally published in the genus Polygonum L. and treated as a variety of P.rotundum Meisn. [≡Persicariajucunda (Meisn.) Migo]. After carefully comparing the macro- and micro-morphological characteristics of the achenes, leaf epidermis and tepals and the habitat between the variety and its typical variety, we confirmed that P.jucundavar.rotunda is clearly different from P.jucunda and should not be treated as a variety, but be raised to a specific rank as P.rotunda (Z.Z.Zhou & Q.Y.Sun) Bo Li. The species is distylous and could be easily distinguished from all other Persicaria taxa by a combination of morphological characters, such as completely decumbent leafless basal branches, almost sessile leaves, linear-lanceolate with rounded leaf bases, spicate, short and dense inflorescences, slender pedicels longer than bracts and dimorphic flowers and achenes. P.rotunda is endemic to several large wetlands of eastern China and usually occurs as one of the dominant species in some plant communities.

Antioxidant Mechanism of Xiaojin Pill () for Treatment of Peyronie's Disease in Rats Based on Matrix Metalloproteinases.

OBJECTIVE: To evaluate the effects of Xiaojin Pill () in the treatment of Peyronie's disease (PD) in a rat model. METHODS: Twenty-four male Sprague-Dawley rats were randomly divided into four groups with 6 in each: sham operation, PD model, vehicle control and Xiaojin Pill groups. The rats in the sham operation group received penile tunica albsginea (TA) injection with 50 µL vehicle, while the rats in the other 3 groups received 50 µL penile TA injection of 50 µg transforming growth factor (TGF)-ß1. Forty-two days after the injection, rats in the vehicle control and Xiaojin Pill groups received 0.5 mL water and Xiaojin Pill solution (107 mg/kg of body weight), respectively by gavage for 28 days, while those in the sham operation and PD model groups did not receive any intervention. After intervention, the expressions of matrix metalloproteinase 2/9 (MMP2/9), nitric oxidesynthase (NOS), superoxide dismutase (SOD) and malondialdehyde (MDA) were measured. RESULTS: Rats in the PD model and vehicle control groups presented obvious fibrosis in corpus cavernosum (CC) and demonstrated a significantly increased expressions of MMP2 and MMP9 in the CC compared with the sham operation group (all P<0.01). In contrast, the expressions of MMP2 and MMP9 in the Xiaojin Pill group were significantly down-regulated (both P<0.01). In addition, the levels of NOS and MDA in CC were significantly increased while the activity of SOD was decreased in the PD model and vehicle control groups compared with the sham operation group (all P<0.01). After Xiaojin Pill treatment, the levels of MDA, NOS and SOD appeared to be corrected (all P<0.01). CONCLUSIONS: Xiaojin Pill could reduce fibrosis in the CC by decreasing the expressions of MMPs, NOS and MDA, and by increasing the activity of SOD. Therefore, Xiaojin Pill might be a therapeutic option for PD.

Hexamethylenetetramine directed synthesis and properties of a new family of alpha-nickel hydroxide organic-inorganic hybrid materials with high chemical stability.

A new family of organic-inorganic hybrid material of alpha-nickel hydroxide formulated as Ni(OH)2-x(An-)x/n-(C6H12N4)y.zH2O (A=Cl-, CH3COO-, SO4(2-), NO3-; x=0.05-0.18, y=0.09-0.11, z=0.36-0.43) with high stability and adjustable interlayer spacing ranging from 7.21 to 15.12 A has been successfully prepared by a simple hydrothermal method. The effects of various anions and hexamethylenetetramine (HMT) on the d values of alpha-nickel hydroxide have been systematically investigated. This family of hybrid materials is of such high stability that they can stand more than 40 days in 6 M KOH. The product with a formula Ni(OH)1.95(C6H12N4)0.11(Cl-)0.05(H2O)0.36 has a high surface area of about 299.26 m2/g and an average pore diameter of about 45.1 A. The coercivity (Hc) value is ca. 2000 Oe for the sample with a d spacing of 13.14 A. Moreover, the prepared alpha-Ni(OH)2 in our experiment is of high stability in strong alkali solution. Such high stability could be derived from strong chelating interactions between the Ni ions and HMT molecules with the interlayers. This high chemical stability could make this material more suitable for the applications.

Ethanol assisted synthesis of pure and stable amorphous calcium carbonate nanoparticles.

Stable monodispersed amorphous calcium carbonate (ACC) nanoparticles can be synthesized in ethanol media by a facile method, and crystallization of ACC is kinetically controlled, resulting in the formation of three polymorphs in a mixed solvent of ethanol-water at different pH values.

Polymer-controlled crystallization of unique mineral superstructures.

The origin of complex superstructures of biomaterials in biological systems and the amazing self-assembly mechanisms of their emergence have attracted a great deal of attention recently. Mimicking nature, diverse kinds of hydrophilic polymers with different functionalities and organic insoluble matrices have been designed for the morphogenesis of inorganic crystals. In this Research News, emerging new strategies for morphogenesis and controlled crystal growth of minerals, that is, selective adsorption and mesoscale transformation for highly ordered superstructures, the combination of a synthetic hydrophilic polymer with an insoluble matrix, a substrate, or the air/solution interface, and controlled crystallization in a mixed solvent are highlighted. It is shown that these new strategies can be even further extended to morphogenesis and controlled crystallization of diverse inorganic or inorganic-organic hybrid materials with structural complexity, structural specialties, and improved functionalities.