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Using density-functional-theory calculations combined with hybrid functional, we investigate the band gaps and built-in electric fields of ZnSnN2/ZnO (001) short-period superlattices. The band gap of ZnSnN2/ZnO (001) superlattice can be tuned from 1.9 eV to 0 eV by varying the thickness of both the ZnSnN2 and ZnO regions. Compared to the III-nitride superlattices, stronger built-in electric fields, induced by the polarizations, form inside the ZnSnN2/ZnO superlattices. The lowest electron and uppermost hole states are mainly localized at the two opposite interfaces of the superlattice, but the tails of the lowest electron states extend over several atomic layers. Based on the electrostatic argument, we demonstrate that variations of the band gap are approximately described by a geometric factor. The influence of the in-plane strain is also discussed. The results will be valuable in the design of ZnSnN2/ZnO heterostructures for electronics and optoelectronics applications. [ABSTRACT FROM AUTHOR]

The band offsets of the ZnO/anatase TiO2 and GaN/ZnO heterojunctions are calculated using the density functional theory/generalized gradient approximation (DFT/GGA)-1/2 method, which takes into account the self-energy corrections and can give an approximate description to the quasiparticle characteristics of the electronic structure of semiconductors. We present the results of the ionization potential (IP)-based and interfacial offset-based band alignments. In the interfacial offset-based band alignment, to get the natural band offset, we use the surface calculations to estimate the change of reference level due to the interfacial strain. Based on the interface models and GGA-1/2 calculations, we find that the valence band maximum and conduction band minimum of ZnO, respectively, lie 0.64 eV and 0.57 eV above those of anatase TiO2, while lie 0.84 eV and 1.09 eV below those of GaN, which agree well with the experimental data. However, a large discrepancy exists between the IP-based band offset and the calculated natural band offset, the mechanism of which is discussed. Our results clarify band alignment of the ZnO/anatase TiO2 heterojunction and show good agreement with the GW calculations for the GaN/ZnO heterojunction. [ABSTRACT FROM AUTHOR]

We investigated the energetic, structural, and electronic properties of neutral O and Zn vacancies in ZnO nanowires with different sizes based on the first-principles calculations using density functional theory. We found that for ZnO nanowire with an O vacancy on the surface the formation energy is not sensitive to the size change. The presence of the surface O vacancy results in the formation of the metal-metal bonds. From the band structure analysis, we predicted that the optical property relating to the O vacancy can be strongly altered with decreasing the nanowire diameter. Moreover, there is a large structural deformation on the surface in the presence of Zn vacancy. The formation of a Zn vacancy in the ZnO nanowire with diameter of 16.4 Å is more favorable than in those with smaller diameters. Furthermore, the O vacancy is nonmagnetic, whereas the Zn vacancy is spin-polarized with a magnetic moment of 2.0 μB on the surface. Our results are helpful for understanding these defects in ZnO nanowires and thus useful for nanodevice design. [ABSTRACT FROM AUTHOR]

Hypertriglyceridemia is infrequently reported as a cause of suboptimal delivery of dialytic therapy in critically ill patients. We report the case of a critically ill liver transplant patient in the Intensive Care Unit who was found to have recurrent filter clotting during continuous renal replacement therapy (CRRT). The patient had increased serum triglycerides (TGs), which was identified approximately 2 weeks into hospitalization and initially believed to be due to prolonged propofol use. The patient's elevated TGs ultimately caused her blood to become lipemic, causing the dialytic circuit to become nonfunctional and placed the patient in imminent danger due to hyperkalemia and metabolic acidosis. Therapeutic plasma exchange was emergently used to lower TG levels, and renal replacement therapy was resumed without any other issues. The patient's persistent hypertriglyceridemia was attributed to a combination of adverse effect of medications and liver graft failure. The high TG level and abnormal liver functions improved after a repeat liver transplantation. [ABSTRACT FROM AUTHOR]

Objective: Bone marrow cell extract (BMCE) was previously reported to restore salivary gland hypofunction caused by irradiation injury. Proteins were shown to be the main active factors in BMCE. However, BMCE therapy requires multiple injections and protein denaturation is a concern during BMCE storage. This study aimed to preserve, by lyophilization (freeze‐drying), the bioactive factors in BMCE. Methods: We developed a method to freeze‐dry BMCE and then to analyze its ingredients and functions in vivo. Freeze‐dried (FD) BMCE, freshly prepared BMCE (positive control), or saline (vehicle control) was injected into the tail vein of mice that had received irradiation to damage their salivary glands. Results: Results demonstrated that the presence of angiogenesis‐related factors and cytokines in FD‐BMCE remained comparable to those found in fresh BMCE. Both fresh and FD‐BMCE restored comparably saliva secretion, increased cell proliferation, upregulated regenerative/repair genes, protected salivary acinar cells, parasympathetic nerves, and blood vessels from irradiation‐damaged salivary glands. Conclusion: Lyophilization of BMCE maintained its bioactivity and therapeutic effect on irradiation‐injured salivary glands. The advantages of freeze‐drying BMCE are its storage and transport at ambient temperature. [ABSTRACT FROM AUTHOR]

The paper is devoted to the study of a new class of conic constrained optimization problems with objectives given as differences of a composite function and a convex function. We first introduce some new notions of constraint qualifications in terms of the epigraphs of the conjugates of these functions. Under the new constraint qualifications, we provide necessary and sufficient conditions for several versions of Farkas lemmas to hold. Similarly, we provide characterizations for conic constrained optimization problems to have the strong or stable strong dualities such as Lagrange, Fenchel–Lagrange or Toland–Fenchel–Lagrange duality. [ABSTRACT FROM AUTHOR]

The -delayed particle emission from the exotic nucleus Si has been studied using a detection system with silicon array and clover-type high-purity germanium (HPGe) detectors. The -delayed charged-particle spectrum and -ray spectrum were identified. The half-life of Si has been determined. A new -delayed proton branch with an energy of 3811keV was observed. The -delayed two-proton emission was confirmed. [ABSTRACT FROM AUTHOR]

Objective A challenge in studying human salivary glands is to maintain the cells ex vivo in their three-dimensional (3D) morphology with an intact native extracellular matrix ( ECM) environment. This paper established a human salivary 3D organotypic slice culture model that could maintain its physiological functions as well as allowing a direct visualization of the cells. Methods Human salivary biopsies from six patients were embedded in agarose and submerged in cold buffer for thin (50 μm) sectioning using a vibratome. 'Salivary slices' were mechanically supported by a porous membrane insert that allowed an air-liquid interface and cultured in serum-free culture media. Cell viability, proliferation, apoptosis, physiological functions, and gene expression were assessed during 14 days of culture. Results Human salivary slices maintained cell survival (70-40%) and proliferation (6-17%) for 14 days ex vivo. The protein secretory (amylase) function decreased, but fluid (intracellular calcium mobilization) function was maintained. Acinar, ductal, and myoepithelial cell populations survived and maintained their 3D organization within the slice culture model. Conclusion The human salivary slice culture model kept cells alive ex vivo for 14 days as well as maintaining their 3D morphology and physiological functions. [ABSTRACT FROM AUTHOR]

The nuclear matrix elements for two-neutrino double-β and zero-neutrino double-β decay of 76Ge are evaluated in terms of the configuration-interaction (Cl), quasiparticle random-phase approximation (QRPA), and interacting boson model methods. We point out deficiencies in all of these models and suggest ways that some of them can be corrected. The final results are obtained from the Cl method corrected for configuration admixtures involving orbitals outside of the Cl configuration space by using results from QRPA, many-body-perturbation theory, and the connections to related observables. The CI two-neutrino matrix element is reduced due to the inclusion of spin-orbit partners and to many-body correlations connected with Gamow-Teller β decay. The Cl zero-neutrino matrix element for the heavy neutrino is enhanced due to particle-particle correlations that are connected with the odd-even oscillations in the nuclear masses. The Cl zero-neutrino matrix element for the light neutrino contains both types of correlations that approximately cancel each other. The uncertainty from short-range correlations is also considered. [ABSTRACT FROM AUTHOR]

The fragment production in collisions of 48-50Ca+12C at 50 MeV/nucleon are simulated via the isospindependent quantum molecular dynamics (IQMD) model followed by the GEMINI code. By changing the diffuseness parameter of neutron density distribution to obtain different neutron skin sizes, the effects of neutron skin thickness (δnp) on projectile-like fragments (PLFs) are investigated. The sensitivity of isoscaling behavior to neutron skin size is studied, from which it is found that the isoscaling parameter a has a linear dependence on δnp. A linear dependence between δnp and the mean N/Z [N (Z) is neutron (proton) number] of the PLF is obtained as well. The results show that thicker neutron skin will lead to smaller isoscaling parameter α and N / Z. Therefore, it may be probable to extract information of neutron skin thickness from isoscaling parameter α and N / Z. [ABSTRACT FROM AUTHOR]

The thermodynamic properties of wurtzite ZnS are investigated by performing ab initio density functional theory and density functional perturbation theory calculations. Using both the local density approximation and generalized gradient approximation for the exchange-correlation potential, we calculate the phonon dispersion curves and the phonon density of states. The calculated phonon frequencies at the center zone for the Raman-active and infrared-active modes (including LO-TO splitting) are assigned. The thermodynamic functions are calculated by using the phonon density of states. The calculated values are in reasonable agreement with experimental data and other calculations. [ABSTRACT FROM AUTHOR]

In today's dynamic market numerous dynamic influencing factors have seriously aggravates the difficulties of inventory planning of the complex distribution networks. This paper proposes a simulation-based hybrid approach for the optimization of the inventory policies in complex distribution networks. The initial multi-echelon inventory policies are handed over to a simulation model, which is capable of modelling complexity and uncertainties of the distribution network and simulating them under respective scenarios. Through comprehensively analysing the KPIs (logistic service level and logistic costs) of this set of multi-echelon inventory policies, their levels of robustness can be clearly ascertained. Based on the simulation results, a metaheuristic-based optimizer regenerates improved (more robust) multi-echelon inventory policies, which are once again comprehensively and precisely evaluated through simulation. This closed feedback loop forms a simulation optimization process that enables the autonomous evolution of multi-echelon inventory policies of complex distribution networks. Since the simulation results can truly reflect the performance of certain inventory policies in real market environment, the new Simulation-Based Hybrid Approach is quite useful for decision making process. [ABSTRACT FROM AUTHOR]

MnOx/TiO2 catalysts doped with sodium were prepared using the impregnation method. According to the results of the selective catalytic reduction (SCR) of NO with NH3, sodium had the strong poisoning effect on MnOx/TiO2 catalysts for NO decomposition. With the help of XRD, H2-TPR, NH3-TPD, TGA and FESEM, the structures and properties of the catalysts were characterised. Results indicated that the addition of sodium would weaken the role of active ingredients in the SCR process. Meanwhile, the reduction peaks of MnOx/TiO2 catalysts doped with sodium slightly shifted to higher temperatures with increasing content of sodium, attributing to the sintering of MnOx and sodium oxides. Based on the FESEM images, some larger particles were observed on the surface after sodium doping, which might be attributed to compounds of sodium manganese oxides. It could be concluded that the addition of sodium decreased the SCR activity of catalyst by slashing electron donation from the MnOx active site. [ABSTRACT FROM AUTHOR]

The shear viscosity of hot nuclear matter is investigated by using the mean free path method within the framework of the isospin-dependent quantum molecular dynamics model. Finite size nuclear sources at different density and temperature are initialized based on the Fermi-Dirac distribution. The results show that shear viscosity to entropy density ratio decreases with the increase of temperature and tends toward a constant value for p ~ p0, which is consistent with the previous studies on nuclear matter formed during heavy-ion collisions. At p ~ J p0, a minimum of n/s is seen at around 7=10 MeV and a maximum of the multiplicity of intermediate mass fragment (A/IMF) is also observed at the same temperature which is an indication of the liquid-gas phase transition. [ABSTRACT FROM AUTHOR]

Based on the framework of the isospin-dependent quantum molecular dynamics (IQMD) model in which the initial neutron and proton densities are sampled according to the droplet model, the correlation between triton-to-³He yield ratio [R(t/³He) = Yield(t)/Yield(³He)] and neutron skin thickness (δnp) in neutron-rich projectile induced reactions is investigated. By changing the diffuseness parameter of neutron density distribution in the droplet model for the projectile to obtain different δnp, the relationship between δnp and the corresponding R(t/³He) in semiperipheral collisions is obtained. The calculated results show that R(t/³He) has a strong linear correlation with δnp for neutron-rich 50Ca and 68Ni nuclei. It is suggested that R(t/³He) could be regarded as a good experimental observable to extract δnp for neutron-rich nuclei because the yields of charged particles triton and ³He can be measured quite precisely. [ABSTRACT FROM AUTHOR]

Background: The elastic–plastic fracture toughness (Jc) is an important mechanical parameter for studying the failure behavior of air plasma-sprayed (APS) thermal barrier coatings (TBC) at high temperatures. Objective: This study aims to: (1) develop an effective test method to characterize the Jc of TBC at high temperatures; (2) acquire accurate Jc data for TBC at high temperatures; (3) analyze the influence of plasticity of top-coat on the Jc characterization. Methods: The elastic–plastic Ramberg–Osgood equation of the ceramic top-coat and the deformation fields of single edge notched tension (SENT) specimens were measured by high-temperature in-situ tension with digital image correlation (DIC) system. The Jc of TBC was calculated by the numerical J-integral with DIC-measured (DIC-J) deformation fields by adopting Ramberg–Osgood equation of the top-coat. The finite element analysis (FEA) method was adopted to analyze the influence of plasticity of top-coat on the Jc characterization. Results: The curves of Jc varying with crack propagation length (Δa) of TBC were obtained and were expressed as JR = 24.47 × [ 1 + 1.0446 × ( Δ a ~ )0.7624] J/m2 and JR = 16.52 × [ 1 + 1.4806 × ( Δ a ~ )0.6742] J/m2 at 800 and 1000 ℃, respectively. Conclusions: A high-temperature in-situ tensile test of SENT specimens combined with the DIC-J method was developed to characterize Jc of TBC. The Jc of TBC displays a rising resistance curve behavior, and FEA results indicated that Jc would be underestimated without considering the plasticity of the top-coat at 800 and 1000 ℃. [ABSTRACT FROM AUTHOR]

A theoretical study on binding orientations and quantitative structure-activity relationship (QSAR) of a novel series of alkene-3-quinolinecarbonitriles acting as Src inhibitors has been carried out by using the docking study and three-dimensional QSAR (3D-QSAR) analyses. The appropriate binding orientations and conformations of these compounds interacting with Src kinase were revealed by the docking studies, and the established 3D-QSAR models show significant statistical quality and satisfactory predictive ability, with high R2 values and q2 values: comparative molecular field analysis (CoMFA) model ( q2 = 0.748, R2 = 0.972), comparative molecular similarity indices analysis (CoMSIA) model ( q2 = 0.731, R2 = 0.987). The systemic external validation indicated that both CoMFA and CoMSIA models possessed high predictive powers with $ R{^2}_{\!\!\!\rm pred} $ values of 0.818 and 0.892, $ {r^2}_{\!\!\!\rm m} $ values of 0.879 and 0.886, $ {r^2}_{\!\!\!\rm m(LOO)} $ values of 0.874 and 0.874, $ r^2_{\rm m(overall)} $ values of 0.879 and 0.885, respectively. Several key structural features of the compounds responsible for inhibitory activity were discussed in detail. Based on these structural factors, eight new compounds with quite higher predicted Src-inhibitory activities have been designed and presented. We hope these theoretical results can offer some valuable references for the pharmaceutical molecular design as well as the action mechanism analysis. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Motivated by the prospects of increased measurement bandwidth, improved signal to noise ratio, and access to the full complex magnetic susceptibility we develop a technique to extract microwave voltages from our high resistance (∼10kΩ) (Ga,Mn)As microbars. We drive magnetization precession with microwave frequency current, using a mechanism that relies on the spin orbit interaction. A capacitively coupled λ/2 microstrip resonator is employed as an impedance matching network, enabling us to measure the microwave voltage generated during magnetisation precession. [ABSTRACT FROM AUTHOR]

We consider the problems of minimizing a DC function under a cone-convex constraint and a set constraint. By using the infimal convolution of the conjugate functions, we present a new constraint qualification which completely characterizes the Farkas-type lemma and the stable zero Lagrange duality gap property for DC conical programming problems in locally convex spaces. [ABSTRACT FROM AUTHOR]

The breakup reactions of 31Cl + 12C at 44A MeV are investigated experimentally. The longitudinal momentum distribution of 30S after one-proton removal from 31Cl has been obtained. By assuming core plus a valence proton structure, the momentum distribution is studied using the few-body Glauber model. The calculation shows that the width of momentum distribution for a valence proton with l = 2 is consistent with the experimental data, which indicates a dominant d-wave component for the valence proton in 31Cl. [ABSTRACT FROM AUTHOR]

The ratio of shear viscosity (η) to entropy density (s) for an equilibrated system is investigated in intermediate-energy heavy-ion collisions below 100A MeV within the framework of the Boltzmann-Uehling-Uhlenbeck model. After the collision system almost reaches a local equilibration, the temperature, pressure and energy density are obtained from the phase-space information and η/s is calculated using the Green-Kubo formulas. The results show that η/s decreases with incident energy and tends toward a smaller value around 0.5, which is not so drastically different from the BNL Relativistic Heavy Ion Collider results in the present model. [ABSTRACT FROM AUTHOR]

Tensile and impact tests were performed on Al-0.63 wt%Cu and Al-3.9 wt%Cu alloys subjected to equal channel angular pressing (ECAP) with different number of passes. Besides the tensile properties, data about the static toughness and the impact toughness were obtained. The strength and the toughness of the Al-Cu alloys were ameliorated and upgraded to a high level collectively. In addition, fracture surface observations show that the fracture behavior of the Al-Cu alloys changes from brittle mode to ductile mode after multi-pass ECAP. [ABSTRACT FROM AUTHOR]

We consider the DC (difference of two convex functions) optimization problem (P)) inf χ∈X {(ƒ1 (χ) - ƒ2(χ)) + (g1(Aχ) - g2(Aχ))}, where ƒ1, ƒ2, g1, and g2 are proper convex functions defined on locally convex Hausdorff topological vector spaces X and Y, and A is a linear continuous operator from X to Y. Adopting different tactics, two types of the Fenchel dual problems of (P) are given. By using the properties of the epigraph of the conjugate functions, some sufficient and necessary conditions for the weak duality of (P) are provided. Sufficient and/or necessary conditions for the strong Fenchel duality, the stable Fenchel duality, and the stable total duality are derived. [ABSTRACT FROM AUTHOR]

Ferromagnetic resonance is the most widely used technique for characterizing ferromagnetic materials. However, its use is generally restricted to wafer-scale samples or specific micro-magnetic devices, such as spin valves, which have a spatially varying magnetization profile and where ferromagnetic resonance can be induced by an alternating current owing to angular momentum transfer. Here we introduce a form of ferromagnetic resonance in which an electric current oscillating at microwave frequencies is used to create an effective magnetic field in the magnetic material being probed, which makes it possible to characterize individual nanoscale samples with uniform magnetization profiles. The technique takes advantage of the microscopic non-collinearity of individual electron spins arising from spin-orbit coupling and bulk or structural inversion asymmetry in the band structure of the sample. We characterize lithographically patterned (Ga,Mn)As and (Ga,Mn)(As,P) nanoscale bars, including broadband measurements of resonant damping as a function of frequency, and measurements of anisotropy as a function of bar width and strain. In addition, vector magnetometry on the driving fields reveals contributions with the symmetry of both the Dresselhaus and Rashba spin-orbit interactions. [ABSTRACT FROM AUTHOR]

A new generation rescheduling model is proposed for transient stability enhancement of power systems, which can optimally reallocate power generations for eliminating potential transient stability threat. The idea of angle norm has been introduced to develop a sensitivity-based transient stability constraints of the rescheduling model. Trajectory sensitivity mapping technique is studied to evaluate the sensitivity factor of the angle norm at maximum swing angle to the power input of generators. The augmented Lagrangian method is employed to solve the rescheduling problem in an iteration manner. Case studies on the IEEE 50-generator test power system are reported to verify the effectiveness of the proposed generation rescheduling method. [ABSTRACT FROM AUTHOR]

Background: Clinical presentation and DYT1 status amongst Chinese patients with primary dystonia have not been well studied. Methods: One hundred and twenty patients with primary dystonia from South-West China were studied in a prospective survey for 3.5 years. Severity and the resulting disability were assessed using the Burke–Fahn–Marsden dystonia rating scale (BFMDRS). Health related quality of life (HRQL) was measured through the 36-item short-form (SF-36). The Hospital Anxiety and Depression Scale (HADS) was utilized to identify and quantify depression and anxiety. Mutations in the DYT1 exon 5 were screened by direct sequencing. Results: Cervical dystonia was found to be the most frequent form of focal dystonia and was discovered to occur at an early age. Pain and tremor were the common associated symptoms. Family history was positive in 19.5% of the cases, with a trend of earlier onset. Depression (14.5%) and anxiety (6.6%) were the main HRQL impairments. Multiple linear regression analysis suggested that gender, depression, anxiety and functional disability were amongst the principal determinants of lower HRQL. Only one instance of DYT1 GAG deletion (1.4%) was detected in 71 patients. Conclusion: Our data on a cohort of Chinese patients show some difference from descriptions in other ethnic groups. This includes an earlier age of onset, a lower incidence of depression and female serving as a predictor factor of a HRQL. Similar to other cohorts, DYT1 gene mutations are rare. [ABSTRACT FROM AUTHOR]

The torch speed is one of the most important operating parameters in thermal spraying. Generally, in order to keep a uniform coating thickness, the movement of the torch should be constant. Nevertheless, when the torch follows a large trajectory angle, the torch speed will decrease significantly, which leads to an irregular coating thickness. This phenomenon is caused by the weight of different devices fixed on the robot and the combination of the robot’s six axes. It is therefore necessary to optimize robot kinematics behaviors in this case. In this paper, the works concentrate mainly on the relationship between the robot kinematics property and the coating quality to find an adequate model for the torch speed optimization. An add-in program based on RobotStudio™ (ABB, Sweden) is developed to determine and optimize the spray trajectory. The optimal trajectory was verified by both the simulations and the experiments. [ABSTRACT FROM AUTHOR]

Experiments of 23Al and 22Mg radioactive beams bombarding a 12C target at an energy of 60 ~70 A MeV have been performed at the projectile fragment separator beamline (RIPS) in the RIKEN Ring Cyclotron Facility to study the two-proton emission from 23Al and 22Mg excited states, respectively. The trajectorie of the decay products, namely 21Na + p + p from 23Al and 20Ne + p + p from 22Mg, are clean identified. The relative momentum and opening angle between two protons in the rest frame of three body decay channels are obtained by relativistic-kinematics reconstruction. The results demonstrate that there are some di-proton emission components from 2He cluster for the excited 23Al and 22Mg. [ABSTRACT FROM AUTHOR]

A two-scale micromechanics scheme is used to analyze domain switching in ferroelectric ceramics during poling. The drastically different polarizability characteristics of Pb(ZrxTi1-x)O3 ceramics across morphotropic phase boundary has been captured, it is demonstrated that a complete poling that exhausts 180° and non-180° domain switching is realistic at MPB but highly unlikely in both tetragonal phase and rhombohedra phase, the effects of the transformation strains are also highlighted. [ABSTRACT FROM AUTHOR]

Background: Despite earlier studies demonstrating in vitro propagation of solid tumour cancer stem cells (CSCs) as non-adherent tumour spheres, it remains controversial as to whether CSCs can be maintained in vitro. Additional validation of the CSC properties of tumour spheres would support their use as CSC models and provide an opportunity to discover additional CSC cell surface markers to aid in CSC detection and potential elimination.Methods: Primary tumour cells isolated from 13 surgically resected colon tumour specimens were propagated using serum-free CSC-selective conditions. The CSC properties of long-term cultured tumour spheres were established and mass spectrometry-based proteomics performed.Results: Freshly isolated CD133(+) colorectal cancer cells gave rise to long-term tumour sphere (or spheroids) cultures maintaining CD133 expression. These spheroid cells were able to self-renew and differentiate into adherent epithelial lineages and recapitulate the phenotype of the original tumour. Relative to their differentiated progeny, tumour spheroid cells were more resistant to the chemotherapeutic irinotecan. Finally, CD44, CD166, CD29, CEACAM5, cadherin 17, and biglycan were identified by mass spectrometry to be enriched in CD133(+) tumour spheroid cells.Conclusion: Our data suggest that ex vivo-expanded colon CSCs isolated from clinical specimens can be maintained in culture enabling the identification of CSC cell surface-associated proteins. [ABSTRACT FROM AUTHOR]

The mutual impedance formula between two arbitrary antenna elements is constructed based on the Fourier analysis in angle dependence and the appropriate choosing of the expansion functions in distance dependence. The unknown coefficients in the formula are obtained through solving simultaneous equations based on numerical sampling by using a full-wave solver or based on the measured data. This formula is applicable to arbitrary types of antenna elements. The two elements could be the same or different. The accuracy of this trained formula is observable by comparing the training set and the testing set. It is therefore controllable. This formula is not only useful in the analysis of the mutual impedance between two isolated elements but also will be useful in array problems where the mutual coupling effect should be taken into account in a finite array environment. The validity of the proposed formula is confirmed through comparisons between the results from this formula and those from the full-wave commercial software. [ABSTRACT FROM AUTHOR]

We have designed and tested a novel electronic tracking antenna array that is formed by 2 x 2 microstrip sub-arrays. Through time sequence phase weighting on each sub-array, the amplitude and phase on each sub-array can be recovered from the output of the resultant single channel. The amplitude and phase on each array can be used to produce the sum and difference radiation pattern by digital signal processing. In comparison with the monopulse system, the RF comparator is eliminated and the number of the receiver channels is reduced from 3 to 1. A proof-of-concept prototype was fabricated and tested. The measured results confirmed the validity and advantages of the proposed scheme. The procedure of channel correction is given. [ABSTRACT FROM AUTHOR]

For an inequality system defined by a possibly infinite family of proper functions (not necessarily lower semicontinuous), we introduce some new notions of constraint qualifications in terms of the epigraphs of the conjugates of these functions. Under the new constraint qualifications, we obtain characterizations of those reverse-convex inequalities which are a consequence of the constrained system, and we provide necessary and/or sufficient conditions for a stable Farkas lemma to hold. Similarly, we provide characterizations for constrained minimization problems to have the strong or strong stable Lagrangian dualities. Several known results in the conic programming problem are extended and improved. [ABSTRACT FROM AUTHOR]

The use of recyclable forms of sulfur will exclude the risk of sediment reacidification and reduce the cost of bioleaching process. Three different forms of sulfur (namely sulfur powder, prills and pieces) were used to examine the utilization and recycle of sulfur, used as energy substrate for sulfur-oxidizing bacteria (SOB) in the bioleaching of heavy metal-contaminated sediments. The results showed that despite their relatively smaller surface areas, the efficiency of metal bioleaching with sulfur prills and pieces were comparable to that with sulfur powder. After 13 days of bioleaching, 71-74% of Zn, 58-62% of Cu, and 22-31% of Cr could be leached from the sediments, respectively. During bioleaching, most of the oxidizable and reducible forms of metals were transformed to acid soluble, posing a favorable condition for final metals removal. Sulfur recycling experiments showed that the recovered sulfur prills and pieces were as the same effective in pH reduction as fresh sulfur, revealing the feasibility of eventual reuse of the recycled sulfur in the bioleaching process. Further studies are required to testify the performance of these recyclable forms of sulfur in future large-scale bioleaching reactor. [ABSTRACT FROM AUTHOR]

Definitions of angle radius and coordinates axis are presented to propose a new transient stability method that is simple and reliable for transient stability assessment. The concept of angle radius is further developed to introduce the novel concept of projection energy function (PEF), which in turn allow to the assessment of critical clearing time and generation limit of system in a new way. The advantage of the new method is that no concept of advanced generator group is required in the assessment contingency stability index. Case studies on the ten-generator New England test power system are reported to verify the validity of the PEF method. [ABSTRACT FROM AUTHOR]

A new model for coordinated optimal design of power system stabilizers (PSSs) is proposed for damping low frequency power oscillation of interconnected power systems and enhancing overall performance of both transient and small-signal stability. In this model, a novel objective function is constructed using rotor speeds of generators in a post disturbed period. Trajectory sensitivity mapping technique is proposed to evaluate the approximate gradients of the objective function relative to the PSS parameters. With the gradients, conjugate gradient method is employed to assess the PSS parameters for minimizing the objective function. Two schemes of gradient formulation and optimization procedure are suggested and compared. The model and effectiveness of the method are verified by eigenvalue assessments and time domain nonlinear simulations on the IEEE four-generator and the ten-generator New England test systems. [ABSTRACT FROM AUTHOR]

According to the equivalent continuum method and coordinates transformation, the anisotropic properties of the stiffness and the strength of planer lattice grid composites were researched. Anisotropic properties of various lattice grid composites with three to five stacks of struts were discussed and compared. The criteria of stiffness isotropy and orthotropy were concluded. Ordinarily, the grid stiffness is anisotropic. But with two or four symmetries the lattice is orthotropic and quasi-isotropic with at least six symmetries. The initial yield or brittle failure strength of typical lattice grid composites was studied and compared. The strength of the lattice grid composite is always anisotropic, even if their stiffness is quasi-isotropic. The degree of anisotropy of the strength is normally stronger than the stiffness anisotropy. With more symmetries, more bar rows and more uniform equivalent rigidities of struts, the variation of the strength gets smaller [ABSTRACT FROM AUTHOR]

A new model describing the uncertainty of fault clearing time for probabilistic transient stability assessment of power systems is proposed. In this, a corrected transient energy function-based strategy is developed to evaluate the probabilistic instability index of systems. The advantage of this approach is that evaluations of critical clearing time in the system stability probability assessment are only conducted for very severe contingencies, an extremely small fraction of all considered contingencies. Hence, the computation efficiency has been remarkably enhanced. Case studies on a representation of the North China power system are reported to show that the proposed assessment strategy is effective and practical. [ABSTRACT FROM AUTHOR]

Recent studies on the relationship between the present rapid expansion of the Chinese economy and the number and type of construction accidents are described. The paper outlines current health and safety legislation and studies on the causes of construction accidents through literature review, statistical analysis and recently undertaken field studies. The results show that the Chinese construction industry, because of rapid expansion, has entered a period in which there is likely to be a proportionally larger number of accidents because of the present lack of knowledge, skills and expertise in both application of health and safety legislation and general accident prevention measures. It is believed that the construction industry and the government can and should work together to reduce the peak value of present accident data. The paper concludes with a discussion of possible countermeasures that might be deployed to control accident rates. [ABSTRACT FROM AUTHOR]

The aim of the present study was to examine Cr removal from tannery sludge by bioleaching method using indigenous sulfur-oxidizing bacteria with special emphasis on the influence of bioleaching process on sludge settleability. Chemical leaching with sulfuric acid was designed as the control. The results showed that the inoculation of sulfur-oxidizing bacteria and the addition of elemental sulfur were effective in removing Cr from tannery sludge. After 144 hours of bioleaching, 98% of Cr could be leached. Although it took only 8 hours to reduce the sludge pH from 7.8 to about 2.0 by chemical leaching as compared to 144 hours for bioleaching treatment, chemical leaching removed only 91% of the total Cr. Regardless of bioleaching and chemical leaching treatments, sludge settleability improved considerably with a decrease in sludge pH. Bioleaching treatment performed better than chemical leaching in terms of the percentage of settled sludge and the effluent suspended solids (ESS) content in sludge supernatant. Nevertheless, further work should be carried out to investigate the precise mechanisms leading to such enhanced sludge settleability during sludge bioleaching process. [ABSTRACT FROM AUTHOR]

ABSTRACT BACKGROUND: Despite a growing body of literature reporting eating disorders (EDs) in non-Western countries in recent years, most of these studies are limited to questionnaire-based surveys or case-series studies. This study aimed to investigate the prevalence and correlates of EDs in Taiwanese high-school students. METHODS: The study subjects consisted of all the female high-school students enrolled in the gifted dance class in 2003 in Taiwan (n=655) and non-dance female students randomly chosen from the same school (n=1251). All the participants were asked to complete self-report questionnaires, including the 26-item Eating Attitudes Test (EAT-26) and the Bulimic Investigatory Test Edinburgh (BITE). All the screen positives and an approximate 10% random sample of the screen negatives were then interviewed using the Structured Clinical Interview for DSM-IV-TR Axis I Disorders Patient Version (SCID-I/P). RESULTS: The prevalence of individual EDs was much higher in the dance [0.7% for anorexia nervosa (AN), 2.5% for bulimia nervosa (BN) and 4.8% for EDs, not otherwise specified (EDNOS)] than in the non-dance (0.1, 1.0 and 0.7% respectively) students. Multivariate logistic regression analyses revealed that being in the dance class, higher concern about body shape and lower family support were correlates of EDs for all students, whereas lower parental education level was associated with EDs only for non-dance students.ConclusionEDs were more prevalent in the weight-concerned subpopulation. Although AN is still rare, BN has emerged as a comparable prevalent disorder in Taiwan, as in Western countries. [ABSTRACT FROM AUTHOR]

The technique of using a coarse model obtained from layout-level synthesis of radio frequency components in neural inverse space mapping (NISM) optimisation technique is proposed. Layout-level synthesis is based on a combination of segmented lump-circuit modelling, nonlinear mapping using neural network (NN) and circuit-level optimisation. The circuit model based on the electromagnetic (EM) simulation describes the important parameters and parasitic parameters and serves as a high-quality coarse model in applying NISM. In implementation of NISM optimisation, trained NN is introduced as a buffer space between the original coarse model space and the fine model space, where the subset of the coarse model space is completely different from that of the fine model space. Stoer–Bulirsch adaptive frequency sampling (S–B AFS) technique is used in frequency sweep of the fine model to further reduce the computing time. An application design of low-temperature ceramic cofired filter is used to demonstrate the proposed technique. Synthesis and optimisation results of the filter meet the design specifications. [ABSTRACT FROM AUTHOR]

A nonlinear programming model for simultaneously coordinated parameters design of power system stabiliser (PSS) and thyristor-based static synchronous compensator (STATCOM) stabiliser is presented. A modified simplex-simulated annealing (MSSA) algorithm is developed for solving the programming model. The MSSA can shift all eigenvalues of the system into specified regions on the s-plane for the preconfigured multiple operational points. The MSSA algorithm combines the merits of conventional simplex and simulated annealing methods together, such as global optimal solution, robustness to initial parameter settings and acceptable convergence speed and so on and also improves the ability of solving constrained optimisation problems. Numerical results including eigenvalue analysis and the nonlinear simulation on the 10-generator New England test power system are presented to indicate the effectiveness and potential engineering applications of the MSSA algorithm. [ABSTRACT FROM AUTHOR]

Context: Although concerns have persisted for decades about the production of new physician clinical scientists and their success in receiving and sustaining research supported by the National Institutes of Health (NIH), no comprehensive analysis documents the experiences of first-time investigators with an MD over a long period.Objective: To ascertain the perseverance and comparative success of physician-scientists competing for NIH research (R01) grants awarded over 40 years.Design, Setting, and Participants: A longitudinal, comparative study of all first-time applicants and recipients of NIH R01 grants between 1964 and 2004 stratified by the principal investigators' major degrees (MD, PhD, or MD and PhD) and their proposed involvement in research of humans or human tissues.Main Outcome Measures: Number of first- and second-time NIH R01 grant applicants and recipients by academic degree and by research type (clinical vs nonclinical).Results: The annual number of first-time investigators with an MD only as NIH R01 grant applicants remained remarkably stable over 4 decades (41-year mean of 707 [range, 537-983] applicants). Among first-time applicants, those with an MD consistently had less success in obtaining funding (mean annual percentage [MAP], 28%) than either investigators with a PhD (MAP, 31%; P = .03 vs MD only) or both an MD and a PhD (MAP, 34%; P<.001 vs MD only and P = .002 vs PhD only). Among investigators who obtained a first R01 grant, those with an MD were consistently less likely (MAP, 70%) than those with a PhD (MAP, 73%; P = .04 vs MD only) or those with an MD and a PhD (MAP, 78%; P<.001 vs MD only and P = .007 vs PhD only) to obtain a subsequent R01 grant. First-time applicants with an MD were much more likely to propose clinical research (MAP, 67%) than applicants with an MD and a PhD (MAP, 43%) and applicants with a PhD only (39%). First-time applicants with an MD only who proposed clinical research were funded at lower rates than their MD-only counterparts proposing nonclinical research (23% vs 29%, respectively; P<.001).Conclusions: From 1964-2004, the number of physician-investigators applying for first R01 grants showed little net change. Physician-investigators consistently experienced higher rates of attrition and failure, even after receiving a first R01 grant, and those proposing clinical research were less successful in obtaining funding than physicians proposing nonclinical research. [ABSTRACT FROM AUTHOR]

This paper presents a new generation rescheduling approach for preventive control of power systems, which can optimally reallocate power generations for multiple unstable contingencies. The transient stability constraints used in the optimal rescheduling model are described by a heuristic stability performance index. A backward integration technique is proposed to evaluate gradient of the performance index. Using the gradient, the functional inequality constraints imposed by unstable contingencies are expressed by linear inequalities, and the rescheduling problem is solved iteratively. Effectiveness of the approach is demonstrated by numerical tests on a representation of North-China power system. [ABSTRACT FROM AUTHOR]