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It is still a challenge to clarify the dependence of overall elastic properties of heterogeneous materials on the microstructures of non-elliposodal inhomogeneities (cracks, pores, foreign particles). From the theory of elasticity, the formulation of the perturbance elastic fields, coming from a non-ellipsoidal inhomogeneity embedded in an infinitely extended material with remote constant loading, inevitably involve one or more integral equations. Up to now, due to the mathematical difficulty, there is almost no explicit analytical solution obtained except for the ellipsoidal inhomogeneity. In this paper, we point out the impossibility to transform this inhomogeneity problem into a conventional Eshelby problem by the equivalent inclusion method even if the eigenstrain is chosen to be non-uniform. We also build up an equivalent model, called the second Eshelby problem, to investigate the perturbance stress. It is probably a better template to make use of the profound methods and results of conventional Eshelby problems of non-ellipsoidal inclusions.

A facile, mild, and relative environmentally friendly procedure for the regeneration of aldehydes and ketones from their oximes with potassium permanganate supported on kieselguhr reagent at room temperature under heterogeneous conditions in the yield between 82–96% is described.

An efficient oxidation of oximes to their corresponding ketones and aldehydes with Jones reagent supported on kieselguhr under heterogeneous conditions at room temperature in the yield between 84 and 93% is described. The present procedure is an extension of application of Jones reagent supported on kieselguhr.

This paper presents a novel method to unwrap phase ambiguity and an expert system to select the direct sound from several reflecting pulses in an USBL positioning system. Generally, in the crossed-shaped USBL array, unwrapping ambiguity in the long edge is based on the absence of ambiguity in the short edge, where the array spacing is less than half-wavelength. However, if the positioning system works at a high frequency, which results in the short-edge phase ambiguity, the classical method to unwrap long-edge ambiguity will fail. This paper proposes a sector searching method for this scenario. It utilizes all combinations of two edges to solve all possible target orientations, and takes the mode as the final result. Additionally, hydrophones receive multi-path reflections besides the direct sound in practical application. The expert system is particularly used for selecting the direct sound correctly, which seriously effects the positioning precision. It contains series of criteria to evaluate the quality of each pulse and considers the pulse with the best quality as the direct sound. Simulation and field experiment results prove that the proposed methods are feasible and can achieve good accuracy. Keywords: USBL; phase ambiguity; expert system; and direct sound.

The recently developed power electronic devices allow the flexibility of power and/or reactive power generation or consumption via electric vehicle charging. It is envisioned that a fleet of electric vehicles may provide auxiliary means for frequency and voltage regulation to improve the power quality and the stability of the power grid. This emerging technology is especially important for microgrid because of the volatility of power generation and consumption in a microgrid due to its diverse and sometimes unpredictable power sources and distributed load. In this work, the intelligent electric vehicle charging control for reduced cost and improved stability of microgrid is formulated as a constrained optimization problem. In order to capture the uncertainties in a microgrid, a discrete-time Markov Decision Process is adopted to model the dynamics of the system. Value iteration and policy iteration are used to solve the problem, and simulation results indicate that the resulted action policy made state transitions towards the stable states, thus scheduled electric vehicle to provide auxiliary regulation services to stabilize the system.

Through carrying out spectral test experiment, the influence factors of spectrum test were analyzed, the influence degree of various factors in spectral recognition was explicated and the method of spectra test was optimized for cotton leaf infected by verticillium wilt. The results indicated that under different severity levels, the shape and value of reflectance of disease symptoms part were Significantly higher than healthy part on cotton leaf, compared with the black board as baseboard, the spectral values of disease leaves were slightly higher in visible light wavebands and significantly higher in others wavebands than healthy leaves on white baseboard. Different position of leaf on cotton plant has different effect degree to the recognition of disease, the effect of stem leaf was more obvious than that of else leaf, the identical leaf position was less influenced by disease than band. Test time and cotton varieties had less influence on recognizing disease by spectra, and the effect of the same condition was acceptable. Test site had no effect on disease recognition by spectra. The effect of each factor was different for recognizing disease leaf by spectra, and this study will provide reference for the researchers of crop disease diagnosis by spectra.

A study of dielectric resonator antenna on silicon substrate with a conductivity of 10S/m is presented. In order to improve antenna efficiency, the high dielectric layer is analyzed to cover the feed line. By covering with dielectric layer, the energy loss is reduced and antenna efficiency increases obviously in the range from 57GHz to 65GHz.

This paper mainly focuses on the minimization of total energy cost and reduction of peak-to-average ratio of energy usage for multiple homes in a community. Taking into account different characteristics of energy usage of a future home, such as whether an electric vehicle (EV) is available, whether the EV is for daily commute, as well as the battery charging characteristics, a constrained optimization problem is formulated. Two pricing schemes are considered, the real-time energy price from The Electric Reliability Council of Texas (ERCOT), and a functional energy price which is not only based on the given ERCOT price pattern changing along with time, but also a function of the usage quantity of electricity during each time interval. It is demonstrated in this study that EV is going to play a major role in future home energy usage, as a result, intelligently charging EV would reduce the electricity cost dramatically and reduce the peak-to-average ratio of electricity usage.

A modified quick, easy, cheap, effective, rugged (QuEChERS) method with multi-walled carbon nanotubes (MWCNTs) as reversed-dispersive solid phase extraction (r-DSPE) material was applied to the analysis of pirimiphos-methyl and deltamethrin residues in stored rice. Two dustable powder (DP) formulations (2% pirimiphos-methyl and deltamethrin DP; 5% pirimiphos-methyl DP) were applied in simulated storehouse trials in the lab. The residues and dissipation of the two pesticides in stored rice were investigated. Slow dissipation of both pesticides was observed in stored rice. The half-lives of pirimiphos-methyl were 23.9–28.9 days, and those of deltamethrin were 23.9–24.8 days. Residues of pirimiphos-methyl from application rates of 4.5–6.75 a.i. mg/kg (active ingredient milligram per kilogram) and 10–15 a.i. mg/kg were 1.6–3.8 mg/kg and 3.0–4.5 mg/kg at 60 days Pre-harvest Interval (PHI). Residues of deltamethrin from an application rate of 0.5–0.75 a.i. mg/kg were 0.13–0.14 mg/kg at 60 days PHI. Both pesticides residues were below the Maximum Residue Limits (MRLs) established by the Codex Alimentarius Commission (CAC). Therefore, at the recommended dosages they are safe for use on stored rice.

In this two-part paper, a thorough investigation is made on Fourier expansions with irreducible tensorial coefficients for orientation distribution functions (oDFs) and crystal orientation distribution functions (CODFs), which are scalar functions defined on the unit sphere and the rotation group, respectively. Recently it has been becoming clearer and clearer that concepts of ODF and CODF play a dominant role in various micromechanically-based approaches to mechanical and physical properties of heterogeneous materials. The theory of group representations shows that a square integrable ODF can be expanded as an absolutely convergent Fourier series of spherical harmonics and these spherical harmonics can further be expressed in terms of irreducible tensors. The fundamental importance of such irreducible tensorial coefficients is that they characterize the macroscopic or overall effect of the orientation distribution of the size, shape, phase, position of the material constitutions and defects. In Part (I), the investigation about the irreducible tensorial Fourier expansions of ODFs defined on the N-dimensional (N-D) unit sphere is carried out. Attention is particularly paid to constructing simple expressions for 2- and 3-D irreducible tensors of any orders in accordance with the convenience of arriving at their restricted forms imposed by various point-group (the synonym of subgroup of the full orthogonal group) symmetries. In the continued work — Part (II), the explicit expression for the irreducible tensorial expansions of CODFs is established. The restricted forms of irreducible tensors and irreducible tensorial Fourier expansions of ODFs and CODFs imposed by various point-group symmetries are derived.

To explore the feasibility of biological method to identify the biological attribute of samples at crime scene.Thirty samples of ten blood stains, ten saliva stains and ten semen stains were selected, and all the samples were processed by the routine method and biomolecular method, respectively. Both RNA and DNA were isolated using DNA-RNA co-extraction technology and the mRNA was converted into cDNA using reverse transcription PCR (RT-PCR). Three pairs of specific primers were designed for blood stain, saliva stain and semen stain based on the different target genes in three specific tissues and the primers were amplified using real-time fluorescent quantitative PCR. The differences in these biological samples were evaluated by melting temperature (Tm) values and the size of the amplification fragment.The Tm values of blood stain, saliva stain and semen stain were (84.5 +/- 0.2) degrees C, (76.9 +/- 0.3) degrees C and (88.5 +/- 0.2) degrees C, respectively. The length of PCR fragments of them was 177bp, 134bp and 294bp, respectively.Compared with the routine method, RT-PCR with real-time fluorescent quantitative PCR is highly specific, sensitive and reliable to identify the biological attribute of evidence, and can be potentially applied to determine evidence attribute in forensic practice.

We have grown epitaxial films, n = 1, 2 and , by pulsed laser deposition (PLD) and controlled their orientation by choosing appropriate substrates. The growth conditions yielding phase-pure films have been mapped out. Resistivity versus temperature measurements show that both a-axis and c-axis films of are metallic, but not superconducting. The latter is probably due to the presence of low-level impurities that are difficult to avoid given the target preparation process involved in growing these films by PLD.

To explore the application value of Expressmarker 22 STR loci direct PCR amplification kit.One thousand nine hundred and forty-eight samples (including samples spotted on FTA cards, filter papers and case samples) were tested using Expressmarker 22 STR loci direct PCR amplification kit. At the same time, all were tested using Sinofiler kit, Identifiler kit and PowerPlex 16 kit respectively for comparison. The genotypes were compared at the same STR loci among these four kits to test the sensitivity and accuracy of Expressmarker 22 STR loci direct PCR amplification kit.97.79% samples were successfully typed using Expressmarker 22 STR loci direct PCR amplification kit. The genotype profiles of the same samples using Expressmarker 22 STR loci direct PCR amplification kit were consistent with Sinofiler kit, Identifiler kit and PowerPlex 16 kit at the same STR loci.Expressmarker 22 STR loci direct PCR amplification kit can provide huge information and accurate results

Manganese dioxide supported on aluminum silicate selectively oxidizes both benzylic alcohols and cinnamyl alcohol to the corresponding aldehydes and ketones, respectively.

In order to ensure the navigation security of unmanned underwater vehicles (UUVs), an underwater acoustic remote control system is essential. An applied remote control method is proposed. The information to be transmitted is modulated both on frequency and pulse intervals. Reliability is guaranteed, and the communication rate is improved at the same time. To reduce the correlation between reverberation and response, opposite chirp rates are used for up-run and down-run instructions. The incoming signal strength, reference signal parameters and the relationship between the incoming signal and the reference signal are utilized to evaluate the hypothesis testing adaptive threshold. A constant false alarm rate (CFAR) detector is realized. Through estimating the channel impulse response, a deconvolution Doppler frequency correction method is proposed. After dividing the band of frame head, a sub-band pre-detector and a copy sequence notch filter are designed to suppress interference from other acoustic platforms. The feasibility and effectiveness of these methods are verified by lake trial results.

In this paper, the problem of energy cost minimization for residential home equipped with electric drive vehicles is considered. In future residential homes, electric drive vehicles, including Hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and all-electric vehicles (EVs), are expected to be common due to the growing energy cost and the need for improving efficiency and energy sustainability. In this context, a constrained optimization problem is formulated for home owners to take advantage of controlling when and how the EVs/PHEVs are charged or discharged in order to minimize their energy cost while keeping the vehicle ready for their daily commute. By taking into account the nonlinear characteristics of the battery charging and discharging, and realistic energy pricing from government agencies such as ERCOT (Electric Reliability Council of Texas), a nonlinear programming solution is derived using the sub-gradient search algorithm. Simulation results demonstrate the effectiveness of the proposed scheme.

This paper focuses on the transferring characteristic and the matching method for interlinked air suspension. Firstly, a structure analysis of parallel air suspension system is given. According to gas thermodynamics and vehicle dynamics, the half vehicle model of the parallel-interlinked air suspension is built. Secondly, the nonlinear dynamic model is linearised by using Taylor series expansion. A comparison analysis of different suspension characteristics between the interlinked and non-interlinked air suspension is carried out. Finally, an experimental study is conducted to validate the simulation results. We found that parallel interlinked air suspension has little effect on the acceleration of the vehicle body during the straight-line driving condition. Most meaningfully, interlinked air suspension could significantly decrease the amplitude of roll angle, which is an important characteristic of the attitude stability. Moreover, the proposed interlinked air springs can reduce the dynamic load of unsprung mass, and improve the road friendliness of vehicles.

Polycondensates containing sulfonate groups, referred to as concrete superplasticizers, are widely used in the construction industry. A sulfanilic acid–phenol–formaldehyde polycondensate (SPF) with Mw ≈ 100.000 g·mol–1 was synthesized from sulfanilic acid, phenol and formaldehyde by polycondensation reaction, and its intercalation into hydrocalumite type Layered Double Hydroxide (LDH) was investigated. Preparation was done by rehydration of tricalcium aluminate, a cement constituent, in the presence of the polymer. According to the XRD pattern, SPF was successfully intercalated. A d value of approx. 2.6 nm was found. Elemental composition of the new organo-mineral phase reveals charge balancing of the cationic LDH main layers by the polycondensate. Thermogravimetry indicates that thermal degradation of intercalated SPF occurs at higher temperature, compared to non-intercalated SPF. According to SEM imaging, the novel Ca-Al-LDH phase exhibits the morphology of intergrown platelets. Ultra-thin nanosheets (foils) with approx. 50 nm thickness were obtained. The layered structure and d value obtained from diffraction analysis were confirmed by TEM imaging. The new hydride can be used as cement and concrete additive.

A new algorithm involving flank array geometry calibration under strong multipath conditions is proposed to address the problem of installation errors and the shell deformation. The derived linear mapping relationship between geometric error of sensors and signal eigenvector reduces the calculating difficulty in near calibration mode. By regarding the reflection as coherent visual sources in known position, the compensation strategy of strong multipath matching is put forward. Cramer–Rao bound (CRB) analysis for the calibration mode is employed. Numerical simulations and lake trials verify the efficiency of the proposed algorithm and illustrate the performance improvement under strong multipath conditions.

Effect of pyruvate on oxidant injury to isolated and cellular DNA. Drawing upon the capacity of pyruvate to detoxify H 2 O 2 , we demonstrate that pyruvate (i) protects against H 2 O 2 -dependent, hydroxyl radical-mediated degradation of isolated DNA; (ii) reduces the amount of 8-hydroxy-2-deoxyguanosine detected following oxidative injury to isolated DNA and (iii) diminishes the amounts of detectable hydroxyl radical generated by a H 2 O 2 -dependent system. Compared to mannitol, pyruvate protects weakly against oxidative degradation of DNA induced by a H 2 O 2 -independent, hydroxyl radical-generating system. The protective effects of pyruvate against H 2 O 2 -instigated DNA damage were also evinced in cells in culture exposed to H 2 O 2 . In contrast to its protective effects against H 2 O 2 -dependent injury to DNA, pyruvate failed to offer convincing protection to another intracellular, H 2 O 2 -vulnerable target, glyceraldehyde-3-phosphate dehydrogenase. The protection conferred by pyruvate to intracellular H 2 O 2 -vulnerable targets is thus influenced by the nature of the target exposed to H 2 O 2 . Pyruvate was markedly protective in a model of cytotoxicity induced by the concomitant depletion of cellular glutathione and inhibition of catalase activity; pyruvate can thus function as an intracellular antioxidant and in this latter model, no evidence of DNA damage was observed. Pyruvate, in contrast to catalase, is a potent protector against cytotoxicity induced by organic peroxides, a finding that cannot be explained by the scavenging of organic peroxides, differences in glutathione content or attenuation in oxidative injury to DNA. We conclude that while DNA damage is a key pathogenetic event in oxidative stress induced by H 2 O 2 , such nuclear changes may not universally subserve a critical role in models of H 2 O 2 -dependent cell death. We also conclude that the antioxidant capabilities of pyruvate extend beyond scavenging of H 2 O 2 to include potent protection against cytotoxicity induced by organic peroxides.

SummaryCell fate decisions are fundamental for development, but we do not know how transcriptional networks reorganize during the transition from a pluripotent to a differentiated cell state. Here, we asked how mouse embryonic stem cells (ESCs) leave the pluripotent state and choose between germ layer fates. By analyzing the dynamics of the transcriptional circuit that maintains pluripotency, we found that Oct4 and Sox2, proteins that maintain ESC identity, also orchestrate germ layer fate selection. Oct4 suppresses neural ectodermal differentiation and promotes mesendodermal differentiation; Sox2 inhibits mesendodermal differentiation and promotes neural ectodermal differentiation. Differentiation signals continuously and asymmetrically modulate Oct4 and Sox2 protein levels, altering their binding pattern in the genome, and leading to cell fate choice. The same factors that maintain pluripotency thus also integrate external signals and control lineage selection. Our study provides a framework for understanding how complex transcription factor networks control cell fate decisions in progenitor cells.PaperClip

Average travel speed is one of the most important indexes for traffic status identification. This paper presents a model to estimate average travel speed based on the data from multi-types floating cars (i.e., taxis, buses, and logistic vehicles). The concept of dynamic road section integration has been proposed to contend with critical issues such as small sample size and large sampling interval. To evaluate the effectiveness of the proposed approach, this paper has also tested the model performance with simulated data from the microscopic simulator VISSIM. Intensive numerical experiments revealed that the average errors of the estimated average speed are less than 7%, which indicates the proposed approach could improve the estimation accuracy significantly.

Passive sonar arrays are often used to find submerged vessels by measuring their radiated signal. Acoustic vector-sensor (AVS) arrays, which are normally towed by the ship at the ends of long cables, have been proven to be very effective for target direction of arrival (DOA) estimation. The flow noise, arising from the flow of water over the vector-sensor or its housing when the array is towed, is often a major source of interference to the towed array as it is usually directly coupled to the array sensing elements. In this paper, we obtain a closed-form expression for the spatial correlations of all the components of an AVS array in a flow-noise field. We apply the noise correlation model to DOA estimation using a uniform linear AVS array beamforming. The flow-noise impact on the beamforming capabilities is evaluated via numerical simulations.

Automatic fare collection system (AFC) has been widely used for public transport all over the world. However, in China, the most important information, the Origin-Destination (OD) matrix of each bus route, cannot be directly obtained from AFC since alighting information is not recorded at each bus stop. This paper presents an OD estimation model, which applies trajectory search algorithms to track passengers' daily trip trajectory using pre-processed smart card data from all the passengers in one city of China. The results of a rigorous validation with on/off data from a real bus route reveal that the proposed model is quite effective and reliable in estimating the OD matrix for identification of the underlying demand pattern of a transit route. The algorithm is validated using oneday smart card data in Jinan city. The results have shown that the OD estimation from the proposed algorithm match more than 75% with the actual ODpairs. During the peak hours, the matching rate goes up to 85%. Hence, the proposed algorithm significantly improves the utilization of the smart card data. It is valuable to evaluate route network and optimize bus scheduling basing on estimated passenger trip OD matrix.

This paper focuses on the analysis of bus crew and vehicle scheduling under the management system commonly-seen in China. With considerations of management rules in practice and related regulations in China, this study proposes a bi-level multi-objective programming model for optimizing the crew and vehicle scheduling for the operation of public bus system. The developed model first estimates the lower bound of the global minimum number of drivers and buses needed in each week. The upper-level model minimizes the difference between the solution and the estimated lower bound and determine the number of vehicles needed; and then the lower-level model tries to minimize the number of drivers needed in each day. A branch and bound solution method has been developed to solve the proposed NP-Hard model, and has been programmed to achieve the computer aided crew and vehicle scheduling. A case study based on four different timetables demonstrated that the estimated lower bounds are with 13% of the global optimization that can ben achieved by the proposed approach. The implementation of the developed method can efficiently reduce the operation cost and support the automated intelligent scheduling for the Advanced Public Transportation System.

Sorting the integers 1 through $N$ into an ordered list is a simple task that can be done rapidly. However, using an algorithm based on the thermally-activated pairwise exchanges of neighboring list elements, we find sorting can display many features of a glass, even for lists as small as $N = 5$. This includes memory and rejuvenation effects during aging --- two hallmarks of glassy dynamics that have been difficult to reproduce in standard glass simulations., 4 pages, 4 figures

The theme of this master project in sociology is to study the relationship between privatisation and income inequality in Western China. The main research theme is whether a higher degree of privatisation is related to greater income inequality. China has experienced massive economic growth in the reform period over the last 30 years. In the planned economy, the private sector was nearly non-existent, and the growth of the private sector has been a central factor in the transformation towards a market economy. The aim of the project is to investigate how this development has affected the wage structures in Western China in respect to income inequality. In the reform period, millions of people have been lifted out of poverty and experienced improved living conditions. However, increased income inequality across many social dimensions has been following in the wake of the economic growth, and created new challenges and social problems. The Western region has been lagging behind in regards to development compared to the coastal provinces, and this regional dimension is important in relation to income inequality in China. I use cross-sectional data from the Medow survey, which was conducted in 2004-2005 in 11 provinces in Western China. The survey was designed and carried out by Fafo, in cooperation with Chinese partners. Medow is the largest living condition survey that has been conducted in Western China, and has data on both household and individual level on a wide range of topics. I use multilevel analysis to study both individual and structural aspects in relation to income inequality. The level of income inequality in a society is influenced by many factors. I chose to focus on five social structures - education, sector, occupation, urban-rural diversity, and migration, and how these social structures affect income inequality, in relation to the process of privatisation. I draw on a range of theoretical perspectives, to frame how privatisation can influence the five social structures, with further consequences for income inequality. I employ neoclassical economic theory with an emphasis on human capital and market mechanisms related to the labour market, market transition theory with a focus on transitional China and increased returns to education, segmented labour market theory which directs attention to the diversified occupational structure, social closure approach with an emphasis on social categories that establishes boundaries and inequality, and neo-Marxism/Structuralism which is related to uneven regional development and migration issues. In general, the main findings confirm that a higher level of privatisation co-exists with greater income inequality between different social groups in Western China. Prefectures with more privatisation tend to have increased income distance between individuals with different educational attainment, between individuals working in the agricultural sector and other sectors, between different occupational positions, between urban and rural citizens, and between migrants and residents. However, income differences between individuals in the state and private sector are found to decline in prefectures with a higher degree of privatisation. There has been much research on income inequality in China within sociology and economy, but less attention has been given to study this in the context of the Western region. There has also been less focus on the relationship between privatisation and income inequality. My study has both an empirical and theoretical purpose. Empirically, my findings challenge the simplistic view that market economic reforms promote equality through development and the “trickle-down” effect of economic growth to wide segments of the population. I show that privatisation in itself not necessarily contributes to increased equality, but can be seen to maintain and create income inequality. Theoretically, the study contributes with a critical discussion of boundaries and processes of social exclusion in the Chinese labour market, and how they are affected by privatisation in the developing market economy. I discuss how different social groups such as peasants, rural migrants, people with low education and low occupational positions have limited possibilities to improve their life chances. An important implication is that the social boundaries are often reinforced by the practice of and ideology behind privatisation.

To solve the conflict between TCP accelerating technology based on PEP middle node and IPSec protocol used in the Satellite Network, NASA and the Hughes Research Laboratory (HRL) each independently proposed a solution named Multilayer IPsec protocol which can integrate IPSec with TCP PEPs. The problem is: Traditional IKE protocol can't work with Multilayer IPSec protocol. In this study, the traditional IKE main mode and quick mode are enhanced for layered IPSec protocol, and an improved layered key distribution protocol: ML-IKE is proposed. This key distribution protocol is used for key exchange between peers and middle node, so that different nodes have different security associations (SA), and different security associations correspond to different IP packet fields, so different SA nodes have different authorization to different IP packet fields. ML-IKE protocol is suitable for layered IPSec, thus layered IPSec can be used for automatic key distribution and update.

As the most advanced rateless fountain codes, Systematic Raptor codes has been adopted by the 3GPP standard as a forward error correction scheme in Multimedia Broadcast/Multicast Services (MBMS). It has been shown to be an efficient channel coding technique which guarantees high symbol diversity in overlay networks. The 3GPP standard outlined a time-efficient maximum-likelihood (ML) decoding scheme that can be implemented using Gaussian elimination. But when the number of encoding symbols grows large, Gaussian elimination need to deal with a large matrix with O (K 3 ) binary arithmetic operations, so the larger K becomes, the worse ML decoding scheme performs. This paper presents a better time-efficient encoding and decoding scheme while maintaining the same symbol recoverable performance, this encoding and decoding scheme is named Rapid Raptor Code. It will be shown that the proposed Rapid Raptor code Scheme significantly improves traditional Raptor codes' efficiency while maintaining the same performance.

The slow compaction of a gently tapped granular packing is reminiscent of the low-temperature dynamics of structural and spin glasses. Here, I probe the dynamical spectrum of granular compaction by measuring a complex (frequency-dependent) volumetric susceptibility $\tilde{\chi}_v$. While the packing density $\rho$ displays glass-like slow relaxations (aging) and history-dependence (memory) at low tapping amplitudes, the susceptibility $\tilde{\chi}_v$ displays very weak aging effects, and its spectrum shows no sign of a rapidly growing timescale. These features place $\tilde{\chi}_v$ in sharp contrast to its dielectric and magnetic counterparts in structural and spin glasses; instead, $\tilde\chi_v$ bears close similarities to the complex specific heat of spin glasses. This, I suggest, indicates the glass-like dynamics in granular compaction are governed by statistically rare relaxation processes that become increasingly separated in timescale from the typical relaxations of the system. Finally, I examine the effect of finite system size on the spectrum of compaction dynamics. Starting from the ansatz that low frequency processes correspond to large scale particle rearrangements, I suggest the observed finite size effects are consistent with the suppression of large-scale collective rearrangements in small systems., Comment: 18 pages, 17 figures. Submitted to PRE

To investigate the in vivo gene expression of adenovirus-mediated human tissue factor pathway inhibitor (hTFPI) and its inhibition effects on intimal proliferation in rabbit carotid arteries after balloon injury.Rabbits underwent carotid artery balloon injuries were treated with Ad-TFPI (n = 25), Ad-LacZ (n = 25) or PBS (n = 10), respectively. Sham operated rabbits (n = 10) serve as normal controls. The expressions of human TFPI at mRNA and protein levels were detected by RT-PCR and ELISA respectively on the 3rd, 7th, 10th, 14th, 28th day after operation. Intimal proliferation was detected by angiograms and morphometric analysis.TFPI mRNA and protein expressions were detected at 3 days and peaked at the 10th and 14th day after TFPI gene transfer. The expressions were still detectable on the 28th day. There was no TFPI expression in Ad-LacZ group. The carotid angiogram results indicated that the minimal lumen diameter in TFPI group was significantly larger and the lumina stenosis percentage was significantly lower in TFPI group compared those in Ad-LacZ and PBS groups (all P0.05). The morphometric analysis showed that the intimal area, the ratio of the intimal/media area, the lumina stenosis percentage in TFPI group were all significantly reduced compared with those in Ad-LacZ and PBS groups (all P0.01).The TFPI gene could be effectively transferred by adenovirus vector to injured carotid arteries and transferred Ad-TFPI could significantly attenuate intimal proliferation in balloon injured carotid arteries in rabbits.

Rigid particles pack into structures, such as sand dunes on the beach, whose overall stability is determined by the average number of contacts between particles. However, when packing spatially extended objects with flexible shapes, additional concepts must be invoked to understand the stability of the resulting structure. Here we study the disordered packing of chains constructed out of flexibly-connected hard spheres. Using X-ray tomography, we find long chains pack into a low-density structure whose mechanical rigidity is mainly provided by the backbone. On compaction, randomly-oriented, semi-rigid loops form along the chain, and the packing of chains can be understood as the jamming of these elements. Finally we uncover close similarities between the packing of chains and the glass transition in polymers., Comment: 11 pages, 4 figures

To evaluate the clinical usefulness of spiral 3-D CT reconstruction for maxillary impacted teeth.Spiral CT was performed in 47 patients whose maxillary impacted teeth couldn't be judged clearly through the panoramic radiograph and occlusal film. 3-D reconstruction, including MIP (maximum intensity projection) and MPR (multiplanar reconstructions) was made to display the impacted teeth's shape, location and its relationship with adjacent teeth.There were 67 maxillary impacted teeth in 47 patients. Spiral 3-D CT could clearly demonstrate the dental image including crown, root, neck and root bifurcation, and 3-D imaging could clearly display the maxilla anatomy and the dental structure.Spiral CT 3-D reconstruction is a useful technique to display three-dimensional configuration of teeth.Three dimensional reconstruction is an accurate and effective method to localize impacted teeth before orthodontic treatment.

Caesalpinia sappan L., which has been used in oriental medicine as an analgesic and antiinflammatory agent, has shown immunosuppressive activity on acute rejection on rat heart allografts. The present study was designed to investigate the potency of protosappanin A, one major ingredient of C. sappan L., in rat heart transplantation.Protosappanin A isolated from an ethanol extract of C. sappan L. was identified by wave spectrum. All groups consisted of Wistar donors into Sprague-Dawley (SD) recipients, including large (25 mg/kg) or small (5 mg/kg) doses of protosappanin A plus cyclosporine (10 mg/kg). A control group was used. Animals were given the drugs on postoperative day 2. We observed graft survival and pathologic conditions of the hearts. Blood samples were obtained on postoperative day 7 to measure the CD4+/CD8+ T-cell ratio. Graft perforin and granzyme B mRNA expression levels were examined with reverse transcription-polymerase chain reaction (RT-PCR) methods.Protosappanin A or cyclosporine significantly prolonged heart allograft survival (P.01), alleviated myocardial pathologic damages (P.01), decreased the CD4+/CD8+ ratio (P.05), and inhibited perforin and granzyme B mRNA expressions in the graft (P.05).These findings demonstrated that protosappanin A prolonged heart allograft survival by significantly attenuating acute rejection.

To investigate the mechanism of "curettage and aspiration" and to conclude its applied technique.2213 complicated abdominal cases, which operation were performed with the PMOD and its "curettage and aspiration" technique from November 1997 to May 2006, were analyzed retrospectively. Meanwhile, the successful rate of operations, the duration of operation, the blood loss of operation and the postoperative complications were statistically analyzed.Each operation was successfully accomplished without damage of the big blood vessels and the biliary tracts. The mean blood loss of pancreatoduodenectomy and radical gastrectomy for cancer, were respectively 105 ml and 75 ml, the mean duration was respectively 3.6 hours and 2.3 hours. As to the acute cholecystitis, the resectable rafe of gallbladder was 100%. Furthermore, no case needs blood transfusion, no massive hemorrhage and concerned damage happened when performing the operation for retroperitoneal tumor.With reasonable operational principles and applied techniques, PMOD (Peng's multifunctional operativedissector) and "curettage and aspiration" technique have demonstrated its specific superiorities in the complicated abdominal operations.

This paper presents a vide-based method for evaluating and validating volume and speed data collected from traffic detectors. Assessing the detector data reliability is a critical task for all Intelligent Transportation Systems (ITS). Their performance will be significantly impacted by the data quality. Most existing studies mainly use volume as the only variable for evaluating the detector quality. A cost-efficient and rigorous method that can concurrently evaluate both volume and speed from the detectors is not yet available. The video-based method presented in this study is both cost-efficient and sufficiently reliable for evaluating detector data for ITS system operations. For example, the performance of a travel time prediction system is very sensitive to the quality of the detector data. This paper will mainly detail the key features of the proposed system and its application in a case study of RTMS detector data on I-70 corridor in Maryland.

Unlike scalar pressure sensors, acoustic vector sensors measure the amplitude and phase of acoustic particle motion in a dedicated direction. An underwater acoustic particle velocity sensor provides significant operational advantages over traditional hydrophones by providing the amplitude and the three dimensional directions of the acoustic signals it senses It can improve performance with a smaller array aperture as compared to the classic scalar hydrophone array. The vector sensor array can estimate the azimuth and elevation angles of the target without left/right ambiguity that occurs in towed array scenario. Within this paper we present an approach to develop a three-axis underwater acoustic vector sensor array and its associated DOA (direction of arrival) estimation algorithm. The physical model of acoustic vector sensor array is introduced and the model is further extended for the implementation rationale with scalar pressure sensing hydrophones. The array performance, especially the array gain of the vector hydrophone array under 3D isotropic ambient noise environment is analyzed as a guideline to develop the vector hydrophone array. A seven-element vector hydrophone array is designed following the theoretical model developed. The characteristics of the vector array proves to be consistent with the theoretical analysis We further introduce the high resolution bearing estimation algorithm of the vector hydrophone array.The vector form M VDR beamforming algorithm is introduced and the performance of the vector hydrophone array and the associated beamforming algorithm are evaluated by an on site trial. The results show that the vector hydrophone array performs well in the estimation of the DOA of both azimuth and elevation of the target.

The consecutive hurricane attacks to US coastline have drawn significant attentions to evacuation operations related issues. To better prepare the state of Maryland for potential hurricanes, this study presents an emergency evacuation system that integrates both optimization and microscopic simulation methods. The optimization module applies a two-level process to generate the preliminary optimal control plans, which is based on a revised cell transmission formulation for large-scale network applications. Using the optimized results as the initial input, the simulation module takes into account various operational constraints and driver responses that are difficult to be captured realistically with mathematical formulations. The proposed system also features its flexibility for potential users to adjust the optimized plans in both the planning phase and real-time operations based on the results of simulation evaluation. The case study with the data from Ocean City, Maryland during hurricane attacks has demonstrated the potential of the proposed system for evacuation of traffic flows in large-scale networks within a given time window.

Myelin figures are long thin cylindrical structures that typically grow as a dense tangle when water is added to the concentrated lamellar phase of certain surfactants. We show that, starting from a well-ordered initial state, single myelin figures can be produced in isolation thus allowing a detailed study of their growth and stability. These structures grow with their base at the exposed edges of bilayer stacks from which material is transported into the myelin. Myelins only form and grow in the presence of a driving stress; when the stress is removed, the myelins retract.

By evaporating a drop of lipid dispersion we generate the myelin morphology often seen in dissolving surfactant powders. We explain these puzzling nonequilibrium structures using a geometric argument: the bilayer repeat spacing increases and thus the repulsion between bilayers decreases when a multilamellar disk is converted into a myelin without gain or loss of material and with number of bilayers unchanged. Sufficient reduction in bilayer repulsion can compensate for the cost in curvature energy, leading to a net stability of the myelin structure. A numerical estimate predicts the degree of dehydration required to favor myelin structures over flat lamellae.

The need to implement an effective incident management systems (IMS) has received increasing attention by general public, media and policy makers, that in turn has required transportation agencies to perform a rigorous evaluation over any implemented plan. Since 1996, the Maryland State Highway Administration (MSHA) has conducted a comprehensive evaluation of its incident response and management program, named CHART. The evaluation study consisted of two phases. Whereas the focus of Phase 1 was on the reliable assess of system performance including incident detection, response, clearance and duration, the core of Phase 2 was to develop the methodology and to estimate resulting system benefits from data available in the CHART incident operations record.

Wakes induced by motion of vessels may extend for tens of kilometers and exist for hours under certain conditions in open sea. This forms a useful feature for long-range ship detection. We present a method for passively detecting a ship wake using measurements obtained by an airborne SQUID magnetic transducer that measures the first-order gradients of the magnetic signature induced by the wake. Analytical formulas of wake magnetic gradients are derived to provide guidelines for designing the airborne detector. We also derive probability bounds of wake detection for cross-correlation and square-law detectors, which can be used to predict the expected performance.

We have grown epitaxial films of Sr 2 RuO 4 , Ba 2 RuO 4 , and Sr 2 TiO 4 and studied their structural and transport properties. These phases are all layered perovskites with the K 2 NiF 4 structure. Sr 2 RuO 4 is the only known superconducting layered perovskite that is free of copper (T c equals 1.35 K in bulk single crystals). In light of the observation that hydrostatic pressure reduces the T c of Sr 2 RuO 4 , we have investigated the effect of replacing Sr 2+ with the larger Ba 2+ ion. In bulk samples, Ba 2 RuO 4 is not isostructural with Sr 2 RuO 4 when synthesized at atmospheric pressure. However, using pressures of 65,000 atm., the synthesis of a tetragonal form of Ba 2 RuO 4 (with the K 2 NiF 4 structure) has been reported. We have grown epitaxial films of the tetragonal form of Ba 2 RuO 4 through the use of epitaxial stabilization. In addition to studying these ruthenates that are isostructural to the high-T c superconductor (La,Sr) 2 CuO 4 , we have also investigated La-doped Sr 2 TiO 4 . Doped SrTiO 3 is a well-known superconductor, but the effect of reducing the dimensionality of SrTiO 3 from 3-D to 2-D (i.e., Sr 2 TiO 4 ) has never been reported. The Sr 2 RuO 4 and Ba 2 RuO 4 films have been grown by pulsed laser deposition (PLD); Sr 2 TiO 4 films have been grown by reactive molecular beam epitaxy (MBE). The growth conditions yielding phase-pure films have been mapped out. The orientation of the epitaxial films has been controlled by choosing appropriate substrates. Resistivity versus temperature measurements show that all three materials exhibit metallic conductivity. A resistivity, (rho) varies direct as T 2 has been observed in many samples at low temperatures, T. However, superconductivity has not been observed in any samples. In addition to growing Sr 2 TiO 4 , the n equals 1 member of the Sr n+1 Ti n O 3n+1 Ruddlesden-Popper homologous series, we also used the atomic layering capability of MBE to grow phase-pure, epitaxial, thin films of the n equals 2 - 5 members of this homologous series (i.e., Sr 3 Ti 2 O 7 , Sr 4 Ti 3 O 10 , Sr 5 Ti 4 O 13 , and Sr 6 Ti 5 O 16 ).