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To explore the incidence and risk factors of readmission of elderly patients with hip fracture after hip hemiarthroplasty.A retrospective analysis of 237 elderly hip fracture patients who underwent hip hemiarthroplasty from February 2015 to October 2020 were performed. According to the readmission status of the patients at 3 months postoperatively, the patients were divided into readmission group (39 cases)and non-readmission group(198 cases). In readmission group, there were 7 males and 32 females with an average age of(84.59±4.34) years old, respectively, there were 34 males and 164 females with average age of (84.65±4.17) years old in non-readmission group. The general information, surgical status, hip Harris score and complications of patients in two groups were included in univariate analysis, and multivariate Logistic regression was used to analyze independent risk factors of patients' readmission.The proportion of complications(cerebral infarction and coronary heart disease) in readmission group was significantly higher than that of non-readmission group (The complications of the elderly patients who were readmission after hip hemiarthroplasty for hip fractures were significantly higher than those who were non-readmission. Cerebral infarction, infection, delirium, dislocation, anemia and venous thrombosis are risk factors that lead to patient readmission. Corresponding intervention measures can be taken clinically based on these risk factors to reduce the incidence of patient readmissions.

Atractylodes macrocephala rhizome (called Bái-zhú in China) has a long history as a functional food and herbal medicine in East Asia, especially China. Sesquiterpenoids are one of the main active compounds of Atractylodes macrocephala rhizome. This study aimed to explore the unknown sesquiterpenoids of A. macrocephala rhizome using a molecular networking strategy. Two new nitrogen-containing sesquiterpenoids, atractylenolactam A (1) and atractylenolactam B (2), and 2 new sesquiterpene lactones, 8-methoxy-atractylenolide V (6) and 15-acetoxyl atractylenolide III (7), along with 12 known analogs (3-5 and 8-16) were discovered and isolated. All the structures were assigned based on detailed spectroscopic analyses. The absolute configurations of 1, 2, 6, and 7 were established by time-dependent density functional theory ECD (TDDFT-ECD) calculations. All these compounds had different degrees of concentration-dependent activating effects on nuclear-factor-E2-related factor-2 (Nrf2).

The aim of this work has been to establish and validate a simple and efficient method to detect the concentration of inulin-type fructan CPA from the roots of Codonopsis pilosula (Franch.) Nannf. in biosamples, and then apply it to evaluate the pharmacokinetics behavior, distribution character in tissue and excretion in mice. In this work, fluorescein isothiocyanate (FITC) was used to label CPA. Then FCPA was intravenously and orally administered to mice at different doses. In both i.v and p.o administration, FCPA concentration slowly declined in the circulatory system with a much longer

For Codonopsis Radix polysaccharides (CRPs), oral administration is generally considered the most convenient route for patients. However, the details of its absorption and transport mechanisms remain unclear. In this study, we aimed to evaluate the oral absorption of CPA (an inulin-type fructan extracted from CRPs) in mice and Caco-2 cells. It was labeled with fluorescein isothiocyanate, and the fluorescence derivative (FCPA) was used to trace the behavior of CPA. The results showed that FCPA could be absorbed after oral administration and has a wide tissue distribution, including in the stomach, intestine, kidneys, and liver. FCPA was poorly absorbed, and its internalization was time- and energy-dependent, as well as dependent on cholesterol- and dynamin-mediated endocytosis. Confocal laser scanning microscopy showed successful cellular internalization of FCPA from the cytoplasm to the nucleus. In addition, we found that FCPA was trafficked to endosomes and lysosomes, and that tubulin was required for its intracellular transport. These findings add new details to our knowledge of the internalization and transport mechanisms of CPA, which may prove useful to the development and application of oral formulations of CRPs.

Background: Emerging evidence suggests that gut microbiota plays a vital role in the occurrence of multiple endocrine disorders including polycystic ovary syndrome (PCOS). Shaoyao-Gancao Decoction (SGD), a classical Chinese prescription, has been widely used in the treatment of PCOS for decades. In previous studies, we found that SGD treatment could effectively reduce ovarian inflammation in PCOS rats. However, whether the anti-inflammation effect of SGD involves the regulation of the gut microbiota remains elusive.Methods: Letrozole-induced PCOS rat models were established, and the therapeutic effects of SGD were evaluated. Specifically, body weight, serum hormone concentrations, estrus phase and ovary histopathology were assessed. Then the structure of gut microbiota was determined by 16s rRNA sequencing. Additionally, the serum levels of pro-inflammatory cytokines and LPS were measured by ELISA kits. The key gene and protein expressions of TLR4/NF-κB signaling pathway were detected by quantitative real-time PCR and western blot.Results: SGD could effectively reduce body weight, regulate estrous cycles and ameliorate hyperandrogenism in PCOS rats. In addition, SGD treatment decreased releases of pro-inflammatory cytokines, enhanced the expressions of tight junction (occludin and claudin1), and then prevented a translocation of LPS into bloodstream. SGD could significantly reduce the ratio of Firmicutes to Bacteroidetes, decrease the abundance of LPS-producing pathogens Proteobateria and enrich the abundance of Butyricicoccus, Coprococcus, Akkermansia Blautia and Bacteroides in PCOS rats. Furthermore, SGD blunted the key gene and protein expressions of TLR4/NF-κB signaling pathway both in vivo and in LPS-induced RAW264.7 cells.Conclusion: SGD administration could ameliorate the inflammatory response in PCOS rats by remodeling gut microbiome structure, protecting gut barrier, and suppressing TLR4/NF-κB signaling pathway.

Two new sesquiterpenes, named selina-4(14),7,11-trien-9-ol (

To enhance maneuvering target tracking in modern battlefield, cognitive radar could adjust its waveforms and information processing manner. In this paper, a novel adaptive waveform design method based on multiple model interaction and measurement information fusion is developed. First, some latest measurements and virtual ones are collected to exploit more robust information. Second, the unknown target state is formulated via the multi-model idea, and the tracking framework is highlighted by the matrix-weighted multi-model fusion (MMF) in lieu of the probability-weighted way. Finally, the MMF output covariance matrix is selected as the ellipse metric, and ellipse parameters can be obtained by using the eigenvalue decomposition. Given these parameters, fractional Fourier transform is used to rotate the measurement error-ellipse to make them orthogonal, and further obtain the desirable rotating orientations for the cognitive transmitting waveform. Simulations show that compared with several algorithms, e.g., MIMM and IMM, our algorithm could further improve tracking performance and robustness.

The unimodular LFM-Syn waveform is formulated by a combination of random noise waveform and conventional LFM, where the phase-scaling factor makes it come true.To achieve low range sidelobes and high Doppler tolerance, a novel template-optimizing function is established with constraints on quadratic phase and random phase.Relaxed Alternating Projection Phase Control method, incorporating spectrum approximation and quadratic phase amendment, is proposed.The LFM-Syn waveform optimized by RAPPC has Doppler tolerance, LPI capability and low range sidelobes. This paper considers the unimodular Linear-FM Synthesized (LFM-Syn) waveform design for cognitive radar.Firstly, the synthesized waveform is formulated by a given phase-scaling factor which combines the random noise waveform and the conventional LFM waveform. Secondly, to achieve low range sidelobes and high Doppler tolerance of LFM-Syn waveforms, a novel template-optimizing objective function is established and then transformed into a two-variable non-convex optimization case with constraints on quadratic phase and random phase. Meanwhile, a Relaxed Alternating Projection Phase Control method (RAPPC) incorporating spectrum approximation relaxed alternating projection and quadratic phase amendment is proposed via an iterative way. RAPPC not only enhances local exploiting for desired waveforms but also keeps high Doppler tolerance and low range sidelobes. Lastly, simulations have provided evidences that the LFM-Syn waveform optimized by RAPPC 1) has high Doppler tolerance similar to conventional LFM, 2) has Low Probability of Intercept (LPI) similar to random noise waveform, and 3) has low range sidelobe levels for prescribed requirement. Additionally, simulations also highlight the superior performance of our proposed algorithms over several existing techniques.

This paper tries to design waveform with low probability of intercept and high doppler tolerance for cognitive radar. Firstly, the novel waveform is formulated by the chaotic-noise waveform and conventional LFM one, where a given phase scaling factor combines them. Then, the template-optimizing function is established with constraints on quadratic phase and chaotic phase, to achieve low range sidelobes. Finally, an approach incorporating spectrum approximation alternating projection and quadratic phase amendment, named Phase-based Alternating Projection Optimized Method (PAPOM), is proposed. Simulations have demonstrated its superior performance. Additionally, results from the matched filter output provide evidence that the novel waveform optimized by PAPOM 1) has range-Doppler resolution similar to conventional LFM one and 2) has Low Probability of Intercept (LPI) similar to random noise-one, as well as 3) has low range sidelobe in specified units.

Hand gesture recognition using radar has been widely applied to control electronic appliances, military appliances and so on. In this paper, we investigate the feasibility of recognizing hand gestures using fused multiple time-frequency signatures, which ensembles micro-Doppler signatures, range-time signatures and angle-time signatures on spectrograms, with an Enhanced Deep Convolutional Neural Network (EDCNN). Several typical gestures included Tick, Double pushing, Rotating clockwise, and Rotating counterclockwise, were measured using Mm-wave radar and their spectrograms investigated. Therein EDCNN was employed to classify the spectrograms, with 80% of the data utilized for training and the remaining 20% for validation. Simulation said that the classification accuracy of the proposed method was found to be 96.2%.

We propose an approach to design locally orthogonal waveform pairs (LOWP). The approach is based on alternating projection, in which an algorithm framework called alternating projections to synthesize LOWP (APLOWP) is derived. Two specialized versions of APLOWP, namely, APLOWP dynamic ideal autocorrelation construction (DIAC) and APLOWP inner product constraint (IPC), are developed. APLOWP-DIAC is used to synthesize waveform pairs for instantaneous polarization radar, because its designed waveforms have very low auto- and cross-correlation magnitudes in specified lag intervals. APLOWP-IPC is used for joint transmit-receive optimization. The IPC of APLOWP-IPC guarantees that the signal-to-noise ratio (SNR) loss is below the specified bound even though a mismatched filter leads to SNR loss. The effectiveness of the proposed algorithms is demonstrated by using numerical simulations.

Calcium phosphate cement (CPC) porous scaffold is widely used as a suitable bone substitute to repair bone defect, but the optimal pore size is unclear yet. The current study aimed to evaluate the effect of different pore sizes on the processing of bone formation in repairing segmental bone defect of rabbits using CPC porous scaffolds. Three kinds of CPC porous scaffolds with 5 mm diameters and 12 mm length were prepared with the same porosity but different pore sizes (Group A: 200-300 µm, Group B: 300-450 µm, Group C: 450-600 µm, respectively). Twelve millimeter segmental bone defects were created in the middle of the radius bone and filled with different kinds of CPC cylindrical scaffolds. After 4, 12, and 24 weeks, alkaline phosphatase (ALP), histological assessment, and mechanical properties evaluation were performed in all three groups. After 4 weeks, ALP activity increased in all groups but was highest in Group A with smallest pore size. The new bone formation within the scaffolds was not obvious in all groups. After 12 weeks, the new bone formation within the scaffolds was obvious in each group and highest in Group A. At 24 weeks, no significant difference in new bone formation was observed among different groups. Besides the osteoconductive effect, Group A with smallest pore size also had the best mechanical properties in vivo at 12 weeks. We demonstrate that pore size has a significant effect on the osteoconductivity and mechanical properties of calcium phosphate cement porous scaffold in vivo. Small pore size favors the bone formation in the early stage and may be more suitable for repairing segmental bone defect in vivo.

The aim of the current study was to prepare microsphere-based composite scaffolds made of nano-hydroxyapatite (nHA)/poly (DL-lactic-co-glycolic acid) (PLGA) at different ratios and evaluate the effects of nHA on the characteristics of scaffolds for tissue engineering application. First, microsphere-based composite scaffolds made of two ratios of nHA/PLGA (nHA/PLGA = 20/80 and nHA/PLGA = 50/50) were prepared. Then, the effects of nHA on the wettability, mechanical strength, and degradation of scaffolds were investigated. Second, the biocompatibility and osteoinductivity were evaluated and compared by co-culture of scaffolds with bone marrow stromal stem cells (BMSCs). The results showed that the adhesion, proliferation, and osteogenic differentiation of BMSCs with nHA/PLGA (50/50) were better than those with nHA/PLGA (20/80). Finally, we implanted the scaffolds into femur bone defects in a rabbit model, then the capacity of guiding bone regeneration as well as the in vivo degradation were observed by micro-CT and histological examinations. After 4 weeks' implantation, there was no significant difference on the repair of bone defects. However, after 8 and 12 weeks' implantation, the nHA/PLGA (20/80) exhibited better bone formation than nHA/PLGA (50/50). These results suggested that a proper concentration of nHA in the nHA/PLGA composite should be taken into account when the composite scaffolds were prepared, which plays an important role in the biocompatibility, degradation rate and osteoconductivity.

A two-stage design approach is proposed to address the sparse antenna array design for multiple-input multiple-output radar. In the first stage, the cyclic algorithm (CA) is used to establish a covariance matrix that satisfies the beam pattern approximation for a full array. In the second stage, a sparse antenna array with a beam pattern is designed to approximate the desired beam pattern. This paper focuses on the second stage. The optimization problem for the sparse antenna array design aimed at beam pattern synthesis is formulated, where the peak side lobe (PSL) is weakly constrained by the mean squared error. To solve this optimization problem, the differential evolution (DE) algorithm with multistrategy is introduced and PSL suppression is treated as an inequality constraint. However, in doing so, a new multiobjective optimization problem is created. To address this new problem, a multiobjective differential evolution algorithm based on Pareto technique is proposed. Numerical examples are provided to demonstrate the advantages of the proposed approach over state-of-the-art methods, including DE and genetic algorithm.

We propose a beamforming algorithm based on waveform diversity for hyperthermia treatment of breast cancer using an ultrasonic array. The introduced array has a structure with a network connecting the feeding nodes and the array elements, and the objective of the algorithm is to train the weight matrix of the network to minimize the difference between the generated beam pattern and the ideal one. The training procedure of the algorithm, which is inspired by the idea of machine learning, comprises three parts: forward calculation, comparison, and backward calculation. The forward calculation maps the weight matrix to the beam pattern, and in the comparison step, the generated beam pattern is modified based on the error, and finally, the backward calculation maps the modified beam pattern to a refined weight matrix which performs better than the original one. An optimal weight matrix is obtained by iterative training. The effectiveness of the algorithm is demonstrated by using numerical simulations.

This paper mainly considers the unimodular Linear-FM synthesized (LFM-Syn) waveform design for cognitive radar. To achieve its low range sidelobes and high Doppler tolerance together, a novel template-based objective function is formulated with constraint on both the quadratic phase and random phase of the waveform. In addition, a novel Alternating Projection Phase Control method (APPC) is proposed to optimize this function. Simulations show some performance of APPC over several existing techniques, and also our waveforms optimized by APPC 1) has Doppler tolerance similar to conventional LFM one and 2) has Low Probability of Intercept (LPI) similar to the random noise one, as well as 3) has low range sidelobes.

We propose an approach to design waveform sets with good auto- and cross-correlation properties. The designed waveform sets can be used for multiple-input multiple-output radars to minimize the cross-interference, and consequently improve the radar performance. Firstly, we transform the original correlation optimization problem into a spectral approximation problem. Secondly, we define the objective function based on the square error between the designed waveform matrix and the ideal one. Finally, the problem is solved by using an algorithm based on alternating projection and phase retrieval. We further improve the proposed method, and derive an extended version to design waveforms with sparse spectrum and good correlation property for combating electronic jamming. The algorithms are computationally efficient because their main steps are based on fast Fourier transform. The effectiveness of the proposed approach is demonstrated by numerical simulations.

We propose an approach for designing unimodular waveforms with low correlation sidelobes in one or more lag intervals. The approach includes an iterative spectral approximation algorithm (ISAA) and derivative-based non-linear optimization algorithms. ISAA is based on power spectral density fitting, phase retrieval, and alternating projection. Phase-only versions of the derivative-based optimization algorithms are also derived. These algorithms eliminate the unimodular constraint by expanding the objective function with respect to the phase vector and by replacing the normal line search with the phase-only line search. The effectiveness of the approach is demonstrated by numerical simulations.

The complex environments of the littoral zones prevent the radar from operating efficiently. We propose a waveform and filter design approach to help the radar improve the performance in littoral zones. The approach includes a phase-only nonlinear programming method for suppressing correlation sidelobes in specified Doppler and range intervals, and an alternating projection based algorithm for designing receive filters. Several numerical examples are provided to demonstrate the usage and effectiveness of the proposed methods.

The K2TiF6,K2ZrF6powder and aluminum were selected as the raw materials to in situ synthesize the particulates reinforced aluminum matrix composites. During the fabrication process the electromagnetic field was imposed. The atomic ratio of Al/Ti/Zr in the particulates is determined as 3/0.4/0.6. The Al3Ti0.4Zr0.6is a new kind of intermetallic compound, some properties of which fall in between those of Al3Ti and Al3Zr. Electromagnetic field plays an important part in fining particles and promoting their uniform distribution. When the electromagnetic induced intensity is 0.05T the particles have 0.5-2μm average size and uniform distribution in matrix. The crystal grains of matrix resemble equiaxed ones. The average size of grains are nearly 100μm, 50μm and 25μm when the electromagnetic induced intensities are 0, 0.025T and 0.05T seperately.

(Al2O3+Al3Zr)P/Al composites were in situ synthesized from Al-Zr(CO3)2system. In the process of in situ reaction, electromagnetic stirring (EMS) is employed to improve the conditions of reaction between reactants powder and melt. The results indicate that the Lorenz force improves the kinetic condition and accelerates the nucleation of endogenetic particulates. The optimized electromagnetic density is 0.025T. Scanning electronic microscope (SEM) observation demonstrates that the sizes of reinforced particulates are controlled at 1~2μm. Moreover, the particulates are well distributed in Al matrix.

To avoid slag sticking onto the snorkel during CAS-OB ladle refining process, B2O3-CaO(mass ratio equals 1:1) and CaF2-CaO(mass ratio equals 1:1) were respectively employed as modifiers added to decrease the viscosity of ladle slag. The rotary cylinder method was adopted in the viscosity measurements. The results showed that the modifiers could decrease the viscosity of ladle refining slag remarkably. At 1500°C, the viscosity of ladle slag without any modifiers is about 6.0 Pa·s. But by adding more than 10mass% CaO-B2O3 or CaO-CaF2, the slag viscosity at 1500°C could be decreased lower than 1.0 Pa·s. The mechanism of modifiers decreasing the slag viscosity was analyzed.

A transient analysis mathematic model was established via ANSYS. The variation laws of magnetic induction density, induced eddy current and electromagnetic force in molten steel changing with the high frequency sine exciting current were investigated. The results indicate that the magnetic induction density and induced eddy current in molten steel vary at the same frequency as exciting current. Moreover, the variations of magnetic induction density and induced eddy current are not in step with exciting current. This proves that the high frequency electromagnetic field in mold and steel is not a time-harmonic wave. The electromagnetic force varies at the double frequency of the exciting current. When the exciting current reaches the amplitude value, the electromagnetic force is close to the max value, whereas when the exciting current returns to zero, the electromagnetic force is not zero. At the same time, there is partial electromagnetic force reversing its direction. If the reversed electromagnetic force is expanded seriously, the fluctuation of liquid level is induced, so it must be controlled.

Synthetic aperture radar seeker (SARS) is the extension in the field of the synthetic aperture technology, and now has become a hot spot in the research and development of radar seeker. In this paper we summarized the research of the SARS related system and imaging guidance related technology. We analyzed the way of long range ballistic missile using matched guidance at the front stage of ballistic trajectory and using target search guidance at the end of ballistic trajectory. Finally we prospect the direction of SARS development.

This paper introduces the advantage and disadvantage of traditional motion compensation way in the stepped-frequency Pulses radar, and analyzes the motion influence on the one-dimension range profile. On the premise of understanding the current speed compensation algorithm, this paper offers an improved method, which is the new two-step approach. This method reduces the operation and enhances the Real-time performance of system. The characteristic of this method is that proposes the concept of the minimum pulse group self adaptive speed researching range. Even though, we don’t have the premise of speed prior knowledge, it also has a well applying prospect and universality. Comparing to the algorithm previously advanced, it has more extensive applications and practicability.

A microsphere composite made of poly(DL-lactic-co-glycolic acid) (PLGA), mesoporous silica nanoparticle (MSN), and nanohydroxyapatite (nHA) (PLGA-MSN/nHA) was prepared and evaluated as bone tissue engineering materials. The objective of this study was to investigate the synergistic effect of MSN/nHA on biocompatibility as well as its potential ability for bone formation. First, we found that this PLGA-MSN/nHA composite performed good characteristics on microstructure, mechanical strength, and wettability. By cell culture experiments, the adhesion and proliferation rate of the cells seeded on PLGA-MSN/nHA composite was higher than those of the controls and high levels of osteogenetic factors such as ALP and Runx-2 were detected by reverse transcriptase polymerase chain reaction. Finally, this PLGA-MSN/nHA composite was implanted into the femur bone defect in a rabbit model, and its ability to induce bone regeneration was observed by histological examinations. Twelve weeks after implantation, the bone defects had significantly more formation of mature bone and less residual materials than in the controls. These results demonstrate that this PLGA-MSN/nHA composite, introducing both MSN and nHA into PLGA microspheres, can improve the biocompatibility and osteoinductivity of compositein vitroandin vivoand had potential application in bone regeneration.

Calcium phosphate cement (CPC) porous scaffold is widely used as a suitable bone substitute to repair bone defect, but the optimal pore size is unclear yet. The current study aimed to evaluate the effect of different pore sizes on the processing of bone formation in repairing segmental bone defect of rabbits using CPC porous scaffolds. Three kinds of CPC porous scaffolds with 5 mm diameters and 12 mm length were prepared with the same porosity but different pore sizes (Group A: 200-300 µm, Group B: 300-450 µm, Group C: 450-600 µm, respectively). Twelve millimeter segmental bone defects were created in the middle of the radius bone and filled with different kinds of CPC cylindrical scaffolds. After 4, 12, and 24 weeks, alkaline phosphatase (ALP), histological assessment, and mechanical properties evaluation were performed in all three groups. After 4 weeks, ALP activity increased in all groups but was highest in Group A with smallest pore size. The new bone formation within the scaffolds was not obvious in all groups. After 12 weeks, the new bone formation within the scaffolds was obvious in each group and highest in Group A. At 24 weeks, no significant difference in new bone formation was observed among different groups. Besides the osteoconductive effect, Group A with smallest pore size also had the best mechanical properties in vivo at 12 weeks. We demonstrate that pore size has a significant effect on the osteoconductivity and mechanical properties of calcium phosphate cement porous scaffold in vivo. Small pore size favors the bone formation in the early stage and may be more suitable for repairing segmental bone defect in vivo.

To obtain efficient non-viral vectors, a series of Gemini cationic lipids with carbamate linkers between headgroups and hydrophobic tails were synthesized. They have the hydrocarbon chains of 12, 14, 16 and 18 carbon atoms as tails, designated as G12, G14, G16 and G18, respectively. These Gemini cationic lipids were prepared into cationic liposomes for the study of the physicochemical properties and gene delivery. The DNA-bonding ability of these Gemini cationic liposomes was much better than their mono-head counterparts (designated as M12, M14, M16 and M18, respectively). In the same series of liposomes, the bonding ability declined with an increase in the tail length. They were tested for their gene-transferring capabilities in Hep-2 and A549 cells. They showed a higher transfection efficiency than their mono-head counterparts and were comparable or superior in transfection efficiency and cytotoxicity to the commercial liposomes, DOTAP and Lipofectamine 2000. Our results convincingly demonstrate that the gene-transferring capabilities of these cationic lipids depended on the hydrocarbon chain length. Gene transfection efficiency was maximal at a chain length of 14, as G14 can silence about 80% of luciferase in A549 cells. Cell uptake results indicate that Gemini lipid delivery systems could be internalised by cells very efficiently. Thus, the Gemini cationic lipids could be used as synthetic non-viral gene delivery carriers for further studies.

Gamma-ray bursts (GRBs) usually occurs in a dense star-forming region with massive circum-burst medium. The small-angle scattering of intense prompt X-ray emission off the surrounding dust grains will have observable consequences, and sometimes can dominate the X-ray afterglow. In most of the previous studies, only Rayleigh-Gans (RG) approximation is employed for describing the scattering process, which works accurately for the typical size of grains (with radius $a\leq 0.1\,{\rm \mu m}$) in the diffuse interstellar medium. When the size of the grains may significantly increase as in a more dense region where GRBs would occur, the RG approximation may not be valid enough for modeling detailed observational data. In order to study the temporal and spectral properties of the scattered X-ray emission more accurately with potentially larger dust grains, we provide a practical approach using the series expansions of anomalous diffraction (AD) approximation based on the complicated Mie theory. We apply our calculations to understanding the puzzling X-ray afterglow of recently observed GRB~130925A which showed a significant spectral softening. We find that the X-ray scattering scenarios with either AD or RG approximation adopted could both well reproduce the temporal and spectral profile simultaneously. Given the plateau present in early X-ray light curve, a typical distribution of smaller grains as in the interstellar medium would be suggested for GRB 130925A., Comment: Accepted for publication in ApJ; 27 pages, 9 figures

This paper deals with the problem of detecting a weak target in compound-Gaussian clutter with inverse gamma texture. An adaptive detector based on two-step generalized likelihood ratio test (GLRT) criterion is presented against this heavy-tailed clutter. The simulation results confirm the effectiveness of the proposed detector. (4 pages)

In order to study the important factors involved in cationic liposome-mediated gene transfer, Lipofectamine 2000 or DOTAP was evaluated using three types of cells (Hep-2, MCF-7 and SW-480) in vitro transfection efficiencies. Different properties of the two reagents were analyzed and compared by DNA arrearage assay and MTT assay. Both Lipofectamine 2000 and DOTAP had strong capability to combine with DNA; Lipofectamine 2000 can get higher transfection efficiency of the three cells by using GFP as report gene, meanwhile, DOTAP can also get higher transfection efficiency against Hep-2 cell. However, DOTAP showed lower transfection efficiency against MCF-7 and SW-480 cell. On the other hand, the cytotoxicity assay showed that over 85% cell viability of MCF-7 cell could be achieved both by Lipofectamine 2000 and DOTAP under the optimal transfection condition. Relatively speaking, Lipofectamine 2000 has very high transfection efficiency in a broad range of cell lines, but because of the special selectivity of cell type on liposome, DOTAP also has a broad application prospect.

This paper proposes a phase-comparison monopulse receiver using pulse-to-pulse frequency agility for a rapid RCS fluctuation of targets and a corresponding angular estimator using multiple observations. Performance is numerically investigated through Monte Carlo simulation and compared with the common MLE of angular deviation. Performance of the estimator is also compared with that of the Swerling I targets model, when frequency agility is not used. (3 pages)

Desertification and degradation of pastures has occurred over the last 50 years on the western grasslands of China due to human factors including overgrazing, unsuccessful reclamation of land, loss of soil through inappropriate cultivation, mining, population growth, and natural factors including drought. This has led to a decrease in herbage mass and a reduction in carrying capacity, leading to a reduction in the sustainability of livestock systems. One of the effects of desertification and degradation has been an increase in the area of poisonous plants over this period and these plants now cover 20.5 m ha and are now a contributing factor and symptom of the degeneration of the grasslands. The main poisonous plants that threaten livestock production are locoweeds (Oxytropis and Astragalus species), Stellera chamaejasme, Achnaterum inebrian, Cynanchum komarovii and Aconitum carmichaeli. Based on an analysis of previous and current data, this review describes the distribution of these poisonous plants and their impact on livestock production and assesses the state of poisonous plants in the western grasslands are having on the sustainability of livestock production, and addresses the issues of integrated control measures and the development of appropriate livestock management systems that could be implemented.

This paper presents a novel in-plane photonic crystal channel drop filter. The device is composed of a resonant cavity sandwiched by two parallel waveguides. The cavity has two resonant modes with opposite symmetries. Tuning these two modes into degeneracy causes destructive interference in bus waveguide, which results in high forward drop efficiency at the resonant wavelength. From the result of numerical analysis by using two-dimensional finite-difference time-domain method, the channel drop filter has a drop efficiency of 96% and a Q value of over 3000, which can be used in dense wavelength division multiplexing systems.

The distributed optical voltage transformer measures voltage through the numerical integration, the choice of the integration points and weights rely on the distribution function of the electrical field. This paper presents a mathematical model of electrical field distribution in distributed optical voltage transformer through calculating electric potential. The simulation results show that the mathematical model reflects the main features of the axial electric field on the central axis of the distributed optical voltage transformer, which indicates that the method to solve the model is feasible. For a optical voltage transformer with a determined structure, the electric field distribution function can be directly obtained by the mathematical model, which could improve the accuracy of measuring the voltage through the numerical integration.