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This article undertakes both theoretical and experimental investigation on the heat and mass transfer properties of wet air and solution (configured sodium hydroxide solution with the concentration of 2%) on the surface of corrugated packings under reduced ambient pressure conditions. Theoretical analysis reveals that a decreased atmospheric pressure environment is conducive to amplifying mass transfer potential difference. However, it concurrently mitigates the maximum possible mass of water vapor per unit volume of air. Subsequently, experiments were carried out under the following conditions: vacuum degree-0 ~ 40 kPa, inlet air velocity-0.8 ~ 1.6 m/s, inlet air temperature-12.0 ~ 22.0 °C, and inlet air relative humidity-50.0 ~ 95.0%. The experimental outcomes indicate that heat transfer coefficient is predominantly influenced by inlet air velocity and vacuum degree. An enhancement of inlet air velocity or a reduction of vacuum degree leads to a corresponding increase of heat transfer coefficient. Under consistent conditions for other parameters, as vacuum degree ascends, moisture absorption rate and efficiency exhibit a steady growth, albeit with a diminishing rate of increment. Under constant inlet air velocity and relative humidity conditions, mass transfer coefficient initially experiences an upsurge as vacuum degree rises, but eventually undergoes a decline. At a fixed inlet air temperature, mass transfer coefficient behaves differently depending on air temperature. It demonstrates a gradual decrease under cooler air temperatures as vacuum degree rises, whereas under warmer air temperatures, it initially increases and then decreases. The analysis reveals that elevating vacuum degree indeed augments mass transfer capability between wet air and solution. However, there exists an upper limit to this enhancement, dictated by the maximum amount of water vapor that wet air can bear upon reaching saturation. [ABSTRACT FROM AUTHOR]

For the first time, the fault tree mapping dynamic Bayesian network (DBN) method is applied to the reliability research study of centrifugal compressor units, and its usability and reliability are evaluated dynamically. First, the fault data using the K-means method eliminates abnormal data and builds a fault tree model. The structure is mapped to the DBN structure to complete the structure learning, and the logic gate is mapped to the conditional probability to achieve the parameter learning. Then the model is solved bidirectionally. The change rule of system node reliability with time is solved forward, and the posterior probability of the system node is solved reversely to complete fault diagnosis. Finally, Monte Carlo simulation analysis and the Markov process verify the dynamic reliability and steady-state availability. The results show that the Monte Carlo simulation method is almost consistent with the reliability prediction curve of the DBN model. Indicating that the accuracy of the DBN model is reliable and the computational efficiency is improved by about 81434 times. The steady-state availability calculated using the DBN model is approximately 0.99963, which is close to reality compared to the Markov process. This method can better describe centrifugal compressor units' dynamic reliability and maintainability and provide decision support for regular maintenance of essential parts and enterprise procurement. [ABSTRACT FROM AUTHOR]

Two sections of the Xintiangou Formation were examined in the Yunyang area, Northeastern Sichuan Basin, China. One of them was systematically sampled from bottom to top. Palynology and geochemistry analyses were performed on 20 samples, and Paleoclimatic indicators were extracted. The sporopollen assemblage indicates arid and hot paleoclimate as a whole, and the geochemical index shows hot and humid paleoclimate. Combined with the analysis of sedimentary characteristics, it shows that the sedimentary period of the Xintiangou Formation in the study area is characterized by arid and hot paleoclimate as a whole, and there were fluctuations of relative moist and arid. The humid climate recorded by geochemical indicators may be the illusion that the unconsolidated sediments transported to the shore shallow lake zone experienced strong weathering. When studying the palaeoclimate characteristics of continental basins, it is necessary to analyze all kinds of palaeoclimate proxy indexes in combination with sedimentary facies, and there may be a deviation in using a single palaeoclimate proxy index to invert the palaeoclimate of continental basins. [ABSTRACT FROM AUTHOR]

Additive manufacturing is expected to transform and upgrade the traditional foundry industry to realize the integrated manufacturing and rapid and low-cost development of high-performance components with complex shapes. The additive manufacturing technology commonly applied in casting mold preparation (fusible molds, sand molds/cores and ceramic cores) mainly includes selective laser sintering (SLS) and binder injection threedimensional printing (3DP). In this work, the research status of SLS/3DPcasting processes on material preparation, equipment development, process optimization, simulation and application cases in aerospace, automotive and other fields were elaborated. Finally, the developing trends of the additive manufacturing technology in the future of foundry field are introduced, including multi-material sand molds (metal core included), ceramic core-shell integration and die-casting dies with conformal cooling runners. [ABSTRACT FROM AUTHOR]

The experimental study of the frictional pressure drop characteristics of flow boiling heat transfer of CO2 in a horizontal minichannel with an inner diameter of Φ1.5 mm was carried out. Experimental conditions: heat flux (7.5 ~ 30 kW•m−2), mass flow rate (50 ~ 600 kg•m−2•s−1), saturation temperature (−40 ~ 0 °C), vapor quality (0 ~ 1). The comparison between the experimental results and theoretical flow pattern diagrams shows that the change of heat flux has little effect on the frictional pressure drop at high vapor quality area, but it has a decisive effect on the dryout and mist flow areas. The mass flow rate is the most important factor affecting the frictional pressure drop which has a decisive effect on the flow pattern experienced during the heat transfer process. The saturation temperature has an important influence on the flow pattern transition characteristics and the friction pressure drop decreases with the increase of saturation temperature. The influence of vapor quality on the frictional pressure drop is mainly caused by the flow pattern change in the minichannel. The flow visualization study shows that the theoretical flow pattern diagram can better reflect the flow pattern of CO2 in the phase-change heat transfer process and the transition trend of flow pattern under different working conditions. [ABSTRACT FROM AUTHOR]

We give a natural Ky Fan minimax inequality version of set-valued maps, and we deal with a type of vector equilibrium problem for set-valued mappings on a special dense set not on the whole domain. We use these results as applications to study the solutions of a generalized set-valued vector variational inequality. [ABSTRACT FROM AUTHOR]

The counter-gravity casting methods have been developed to remove the casting defects of Mg based alloys. However, the effects of different counter-gravity casting methods on the microstructure and mechanical properties have not been studied in detail. ZM5 alloys were prepared by gravity casting, low-pressure casting and counter-pressure casting, respectively. The mechanical properties, microstructure and fracture morphologies were examined and compared by means of optical microscopy, scanning electron microscopy methods and tensile testing. Results show that casting defects such as gas pore, shrinkage porosity and cavity can be eliminated by counter-pressure casting. The grain size of α-Mg is decreased significantly by counterpressure casting. Moreover, the precipitated particles are more uniform and finer in the counter-pressure casting sample. As a result, the mechanical properties of the alloys are greatly improved. The tensile strength and elongation of the samples by counter-pressure casting are 285 MPa and 13.9%, respectively, which are much higher than those of the low pressure casting and gravity casting. [ABSTRACT FROM AUTHOR]

White grub flukes, Posthodiplostomum minimum centrarchi (Trematoda), and hookworms Pomphorhynchus bulbocolli (Acanthocephala) are common internal parasites for many North American freshwater fishes. P. minimum are found as cysts in internal organ tissues, while P. bulbocolli are found as sexually mature adults in gastrointestinal (GI) tracts. Stable isotopes of carbon and nitrogen (δ13C and δ15N) are commonly used to infer food web relationships in freshwater lakes. To see if δ13C and δ15N could be used to analyze parasite-host relationships, we analyzed the stable isotopes of the two species of parasites and various tissue types of their fish hosts (bluegill and pumpkinseed sunfish) from different host tissues. The samples δ13C and δ15N demonstrated that P. minimum and P. bulbocolli fed on the fish hosts livers and intestines, respectively. It is also corroborated by correlations in C/N ratios of those fish parasites and their fish host tissues. This study highlights the importance of identifying the specific host tissues parasites feed on in stable isotope analysis. [ABSTRACT FROM AUTHOR]

The multi-antenna synchronized receiver (using a common clock) is widely applied in GNSS-based attitude determination (AD) or terrain deformations monitoring, and many other applications, since the high-accuracy single-differenced carrier phase can be used to improve the positioning or AD accuracy. Thus, the line bias (LB) parameter (fractional bias isolating) should be calibrated in the single-differenced phase equations. In the past decades, all researchers estimated the LB as a constant parameter in advance and compensated it in real time. However, the constant LB assumption is inappropriate in practical applications because of the physical length and permittivity changes of the cables, caused by the environmental temperature variation and the instability of receiver-self inner circuit transmitting delay. Considering the LB drift (or colored LB) in practical circumstances, this paper initiates a real-time estimator using auto regressive moving average-based (ARMA) prediction/whitening filter model or Moving average-based (MA) constant calibration model. In the ARMA-based filter model, four cases namely AR(1), ARMA(1, 1), AR(2) and ARMA(2, 1) are applied for the LB prediction. The real-time relative positioning model using the ARMA-based predicting LB is derived and it is theoretically proved that the positioning accuracy is better than the traditional double difference carrier phase (DDCP) model. The drifting LB is defined with a phase temperature changing rate integral function, which is a random walk process if the phase temperature changing rate is white noise, and is validated by the analysis of the AR model coefficient. The auto covariance function shows that the LB is indeed varying in time and estimating it as a constant is not safe, which is also demonstrated by the analysis on LB variation of each visible satellite during a zero and short baseline BDS/GPS experiment. Compared to the DDCP approach, in the zero-baseline experiment, the LB constant calibration (LBCC) and MA approaches improved the positioning accuracy of the vertical component, while slightly degrading the accuracy of the horizontal components. The ARMA(1, 0) model, however, improved the positioning accuracy of all three components, with 40 and 50 % improvement of the vertical component for BDS and GPS, respectively. In the short baseline experiment, compared to the DDCP approach, the LBCC approach yielded bad positioning solutions and degraded the AD accuracy; both MA and ARMA-based filter approaches improved the AD accuracy. Moreover, the ARMA(1, 0) and ARMA(1, 1) models have relatively better performance, improving to 55 % and 48 % the elevation angle in ARMA(1, 1) and MA model for GPS, respectively. Furthermore, the drifting LB variation is found to be continuous and slowly cumulative; the variation magnitudes in the unit of length are almost identical on different frequency carrier phases, so the LB variation does not show obvious correlation between different frequencies. Consequently, the wide-lane LB in the unit of cycle is very stable, while the narrow-lane LB varies largely in time. This reasoning probably also explains the phenomenon that the wide-lane LB originating in the satellites is stable, while the narrow-lane LB varies. The results of ARMA-based filters are better than the MA model, which probably implies that the modeling for drifting LB can further improve the precise point positioning accuracy. [ABSTRACT FROM AUTHOR]

The mode-selective microwave reflector with periodic rectangular corrugations in the inner surface of a circular metallic waveguide is studied in this paper. The relations between the bandwidth and reflection coefficient for different numbers of corrugation sections were studied through a global optimization method. Two types of reflectors were investigated. One does not consider the phase response and the other does. Both types of broadband reflectors operating at W-band were machined and measured to verify the numerical simulations. [ABSTRACT FROM AUTHOR]

Ti is regarded as one of the promising grain refiners in cast Al-Li-Cu alloys, but few research works have been done on its independent role. In this study, the effect of Ti on the microstructure evolution and mechanical properties of cast Al-2Li-2Cu-0.5Mg base alloy was investigated. The results revealed that the grains can be prominently refined with the increase of Ti addition. After adding Ti, high density TiB2-Al3Ti composite particles with a low lattice misfit form as heterogeneous nucleation sites for the α-Al matrix. δ'(Al3Li) and T1(Al2CuLi) precipitates that provide enhanced strength are dominated in the alloys after T6 aging treatment. The average size of both δ' and half-width of δ'-precipitation free zone (PFZ) decreases gradually with the increase of Ti content. This is because the higher binding energy between Ti atoms and vacancies limits the diffusion efficiency of Li atoms, and thus results in a higher ductility. Additionally, no nano-sized Al3Ti or core-shell structure of Al3(Li, Ti) particles are found. The tensile property test results indicate that the Al-2Li-2Cu-0.5Mg alloy achieves optimal properties after aging at 175 °C for 32 h when 0.15wt.% Ti is added. It exhibits a yield strength of 352±5 MPa, an ultimate tensile strength of 423±6 MPa, and an elongation of (3±0.4)%. These findings are expected to offer a reliable theoretical guidance for the industrial composition design of the Al-Li-Cu series cast alloys. [ABSTRACT FROM AUTHOR]

Low-latency high-rate ( $$>$$ 1 Hz) precise real-time kinematic (RTK) can be applied in high-speed scenarios such as aircraft automatic landing, precise agriculture and intelligent vehicle. The classic synchronous RTK (SRTK) precise differential GNSS (DGNSS) positioning technology, however, is not able to obtain a low-latency high-rate output for the rover receiver because of long data link transmission time delays (DLTTD) from the reference receiver. To overcome the long DLTTD, this paper proposes an asynchronous real-time kinematic (ARTK) method using asynchronous observations from two receivers. The asynchronous observation model (AOM) is developed based on undifferenced carrier phase observation equations of the two receivers at different epochs with short baseline. The ephemeris error and atmosphere delay are the possible main error sources on positioning accuracy in this model, and they are analyzed theoretically. In a short DLTTD and during a period of quiet ionosphere activity, the main error sources decreasing positioning accuracy are satellite orbital errors: the 'inverted ephemeris error' and the integration of satellite velocity error which increase linearly along with DLTTD. The cycle slip of asynchronous double-differencing carrier phase is detected by TurboEdit method and repaired by the additional ambiguity parameter method. The AOM can deal with synchronous observation model (SOM) and achieve precise positioning solution with synchronous observations as well, since the SOM is only a specific case of AOM. The proposed method not only can reduce the cost of data collection and transmission, but can also support the mobile phone network data link transfer mode for the data of the reference receiver. This method can avoid data synchronizing process besides ambiguity initialization step, which is very convenient for real-time navigation of vehicles. The static and kinematic experiment results show that this method achieves 20 Hz or even higher rate output in real time. The ARTK positioning accuracy is better and more robust than the combination of phase difference over time (PDOT) and SRTK method at a high rate. The ARTK positioning accuracy is equivalent to SRTK solution when the DLTTD is 0.5 s, and centimeter level accuracy can be achieved even when DLTTD is 15 s. [ABSTRACT FROM AUTHOR]

A bounded linear operator T on a Banach space X is called subspace-hypercyclic for a nonzero subspace M if orb (T, x) ∩ M is dense in M for a vector x ∊ X, where orb(T, x) = {Tnx : n = 0, 1, 2, ... }. Similarly, the bounded linear operator T on a Banach space X is called subspace-supercyclic for a nonzero subspace M if there exists a vector whose projective orbit intersects the subspace M in a relatively dense set. In this paper we provide a Subspace-Supercyclicity Criterion and offer two equivalent conditions of this criterion. At the same time, we also characterize other properties of subspacesupercyclic operators. [ABSTRACT FROM AUTHOR]

The linear function is possibly the simplest and the most used relation appearing in various areas of our world. A linear relation can be generally determined by the least square linear fitting (LSLF) method using several measured quantities depending on variables. This happens for such as detecting the gradient of a magnetic field. Here, we propose a quantum fitting scheme to estimate the magnetic field gradient with N-atom spins preparing in Wstate. Our scheme combines the quantum multi-parameter estimation and the least square linear fitting method to achieve the quantum Cramér-Rao bound (QCRB). We show that the estimated quantity achieves the Heisenberg-scaling accuracy. Our scheme of quantum metrology combined with data fitting provides a new method in fast high precision measurements. [ABSTRACT FROM AUTHOR]

In this paper, we obtain an inequality for the normalized Casorati curvature of slant submanifolds in quaternionic space forms by using T Oprea's optimization method. [ABSTRACT FROM AUTHOR]

Experiments on polycrystalline metallic samples have indicated that Grain boundary (GB) structure can affect many material properties related to fracture and plasticity. In this study, atomistic simulations are employed to investigate the structures and mechanical behavior of both symmetric and asymmetric Σ5[0 0 1] tilt GBs of copper bicrystal. First, the equilibrium GB structures are generated by molecular statics simulation at 0K. The results show that the Σ5 asymmetric GBs with different inclination angles (ϕ) are composed of only two structural units corresponding to the two Σ5 symmetric GBs. Molecular dynamics simulations are then conducted to investigate the mechanical response and the underlying deformation mechanisms of bicrystal models with different Σ5 GBs under tension. Tensile deformation is applied under both 'free' and 'constrained' boundary conditions. Simulation results revealed different mechanical properties of the symmetric and asymmetric GBs and indicated that stress state can play an important role in the deformation mechanisms of nanocrystalline materials. [ABSTRACT FROM AUTHOR]

Prior to their fertilization, oocytes undergo asymmetric division, which is regulated by actin filaments. Recently, WASH complex were identified as actin nucleation promoting factors (NPF) that activated Arp2/3 complex. However, the roles of WASH complex remain uncertain, particularly for oocyte polarization and asymmetric division. Here, we examined the functions of two important subunits of a WASH complex, WASH1 and Strumpellin, during mouse oocyte meiosis. Depleting WASH1 or disrupting Strumpellin activity by WASH1 morpholino (MO) injection or Strumpellin antibody injection decreased polar body extrusion and caused oocyte symmetric division, and this may have been due to spindle formation and migration defects. Time lapse microscopy showed that actin filaments distribution and relative amount at the membrane and in the cytoplasm of oocytes was significantly decreased after disrupting WASH complex. In addition, Arp2/3 complex expression was reduced after WASH1 depletion. Thus, our data indicated that WASH complex regulated Arp2/3 complex and were required for cytokinesis and following polar body extrusion during mouse oocyte meiotic maturation. [ABSTRACT FROM AUTHOR]

Depression is a debilitating psychiatric disorder and a growing global public health issue. However, the relationships between microbial infections and depression remains uncertain. A computerized literature search of Medline, ISI Web of Knowledge, PsycINFO, and the Cochrane Library was conducted up to May 2013, and 6362 studies were initially identified for screening. Case-control studies detected biomarker of microorganism were included. Based on inclusion and exclusion criteria, 28 studies were finally included to compare the detection of 16 infectious agents in unipolar depressed patients and healthy controls with a positive incident being defined as a positive biochemical marker of microbial infection. A customized form was used for data extraction. Pooled analysis revealed that the majority of the 16 infectious agents were not significantly associated with depression. However, there were statistically significant associations between depression and infection with Borna disease virus, herpes simplex virus-1, varicella zoster virus, Epstein-Barr virus, and Chlamydophila trachomatis. [ABSTRACT FROM AUTHOR]

In this paper, by using the least action principle in critical point theory, we obtain some existence theorems of periodic solutions for p(t)-Laplacian system { d/dt(| u˙(t) |p(t)-2u˙(t)) = ∇F(t,u(t)) a.e. t ϵ [0,T] u(0) - u(T) = u˙(0) - u˙(T) = 0, which generalize some existence theorems. [ABSTRACT FROM AUTHOR]

In this study, we analyze results from 47-year (1954-2000) offline simulations using an Australian land-surface model CSIRO Atmosphere Biosphere Land Exchange. We focus on exploring its surface mean climatology, interannual and decadal variations in Australia and Amazonia basin in South America which are distinguished by dry and wet climates respectively. Its skill is assessed by using observational datasets and four model products from the Global Land-surface Data Assimilation System. Surface evaporation and runoff climatologies are satisfactorily simulated, including surface energy and water partitions in dry and wet climates. In the Australian continent dominated by dry climate, slowly varying soil moisture processes are simulated in the southeast during austral winter. The model is skilful in reproducing the nonlinear relationship between rainfall and runoff variations in the southwestern part of the Australia. It shows that the significant downward trend of river inflow in the region is associated with enhanced surface evaporation which is caused by increased surface radiation and wind speed. In its carbon-cycle modeling, the model simulates an upward trend of NPP by about 0.69%/year over the Amazonia forest region in the 47-year period. By comparing two sets of the model results with/without CO variations, it shows that 35% of such increases are caused by changes in climatic conditions, while 65% is due to the increase in atmospheric CO concentration. Given the close linkage between climate, water and vegetation (carbon cycle), this work promotes an integrated modeling and evaluation approach for better representation of land-surface processes in Earth system studies. [ABSTRACT FROM AUTHOR]

We have compared the induction of an endoglucanase (EG1) by α-lactose and/or cellobiose, with or without added l-sorbose, in submerged cultures of Volvariella volvacea, to better understand the mechanism whereby cellulase formation is triggered by these soluble disaccharides. EG1 levels induced by α-lactose and cellobiose were 28.6% and 6.7%, respectively of the highest levels recorded with crystalline cellulose. Sorbose did not induce EG1 and strongly repressed enzyme levels when added to α-lactose but not cellobiose-containing cultures. EG1 levels in cultures containing all three saccharides were similar to those recorded with sorbose and cellobiose although enzyme induction was delayed by 12 h. When V. volvacea was pre-grown for 24 h in medium containing sorbose as the sole carbon source, followed by addition of α-lactose or cellobiose or a mixture of the two, EG1 levels recorded in the α-lactose-supplemented cultures were again markedly lower compared with cultures containing only α-lactose. Maximal enzyme levels in cultures with added cellobiose or cellobiose and α-lactose were not affected although appearance of EG1 in culture supernatants was again delayed by 12 h. Semi-quantitative RT-PCR revealed that higher, more prolonged, levels of eg1 transcription occurred in V. volvacea cultures induced with α-lactose compared with cellobiose- or α-lactose + cellobiose-induced cultures. However, eg1 transcription levels in cultures induced with cellobiose or with cellobiose + lactose, and the corresponding cultures with added sorbose, were not markedly different. [ABSTRACT FROM AUTHOR]

The measured strains in the continuously reinforced concrete pavement (CRCP) cannot simply be used to calculate the concrete stresses by multiplying the elastic modulus of concrete, because the measured strains include both the stress dependent and independent strains. The setting temperature of concrete and the measured strain at this temperature should be used to calculate the temperature difference and the strain increment. The early-age strains in the concrete and steel of CRCP were measured in this paper. The measured concrete strains include the total strain, the stress independent strain and the initial strain at setting temperature. These measured values can be used not only to accurately calculate the stresses in concrete and steel but also to determine the accurate boundary conditions in the numerical modeling of CRCP subject to environmental loading. On the boundary conditions used in analysis of the early-age CRCP under environmental loading, epoxy coated steel is not completely bonded with concrete. Additionally, the perfectly free or restrained boundary condition across cracking is not true, and the longitudinal steel strains across cracking will help develop the proper boundary condition across cracking. The calculated stress was verified from the comparison between the calculated stress at the instant of cracking and the measured tensile strength. [ABSTRACT FROM AUTHOR]

A bump develops when there is differential settlement between a bridge abutment and an approach embankment. The determination of the allowable differential settlement is important for the design and maintenance of the bridge approach, so it is studied theoretically in this paper. Because the longitudinal roughness in the bridge approach is much more serious than that in general highway sections, the pitch movement of vehicles cannot be ignored. One adds rider and seat to a half-truck model to build a five- degree-of-freedom vehicle model. The dynamic response analysis to Man-Vehicle-Road system passing over the bridge approaches with and without approach-relative slopes are carried out by means of the Laplace transform. Comparative calculations show that much difference will be produced in the maximum transient vibration value of the acceleration and the vibration frequency when different vehicle models are used. So it is more reasonable to use the five-degree-of-freedom vehicle model than to use the three-degree-of-freedom vehicle model for the determination of the allowable differential settlement. After all the required parameters are determined, the allowable differential settlement can be obtained by trial calculations. [ABSTRACT FROM AUTHOR]

Telomeres are eukaryotic protein–DNA complexes found at the ends of linear chromosomes that are essential for maintaining genome integrity and are implicated in cellular aging and cancer. The guanine (G)-rich strand of telomeric DNA, usually elongated by the telomerase reverse transcriptase, can form a higher-order structure known as a G-quadruplex in vitro and in vivo. Several factors that promote or resolve G-quadruplexes have been identified, but the functional importance of these structures for telomere maintenance is not well understood. Here we show that the yeast telomerase subunit Est1p, known to be involved in telomerase recruitment to telomeres, can convert single-stranded telomeric G-rich DNA into a G-quadruplex structure in vitro in a Mg2+-dependent manner. Cells carrying Est1p mutants deficient in G-quadruplex formation in vitro showed gradual telomere shortening and cellular senescence, indicating a positive regulatory role for G-quadruplex in the maintenance of telomere length. [ABSTRACT FROM AUTHOR]

Maintenance of appropriate iron homeostasis in the brain is important, but the mechanisms involved in brain iron uptake are incompletely understood. Here, we have analyzed where messenger RNAs that encode iron transport proteins are expressed in the brain, using the Allen Brain atlas, and we conclude that several important iron transporters are highly expressed in the choroid plexus. Based on recent estimates of the surface area of the choroid plexus and on MRI imaging studies of manganese uptake in the brain, we propose that the choroid plexus may have a much greater role than has been previously appreciated in brain iron transport. [ABSTRACT FROM AUTHOR]

An animal model of transected spinal cord injury (SCI) was used to test the hypothesis that cografted human umbilical mesenchymal stem cells-derived neurospheres (HUMSC-NSs) and BDNF can promote morphologic and functional recoveries of injured spinal cord. In vitro, HUMSC-NSs terminally differentiated into higher percentages of cells expressing neuronal markers: β-tubulin III and MAP2ab by the supplement with BDNF. Following grafted into injured spinal cord, very few grafted cells survived in the HUMSC-NSs + BDNF-treated (<3%) and HUMSC-NSs-treated (<1%) groups. The survived cells were differentiated into various cells, which were confirmed by double staining of BrdU and neural or glia markers. In comparison, more grafted cells in the HUMSC-NSs + BDNF group transformed into mature neural-like cells, while more grafted cells in the HUMSC-NSs group transformed into oligodendrocyte-like cells. HUMSC-NSs + BDNF-treated group had more greatly improved BBB scores, compared with HUMSC-NSs-treated and medium-treated groups. Additionally, axonal regeneration showed significant improvement in rats receiving HUMSC-NSs + BDNF, compared with HUMSC-NSs-treated and medium-treated groups, as demonstrated by the NF-200-positive staining and Fluorogold (FG) retrograde tracing study. Lastly, a significant reduction in the percentage cavitation was seen in the two cell-treated groups compared with medium control group. These results means BDNF could promote the neural differentiation of HUMSC-NSs in vitro and in vivo. However, cellular replacement is unlikely to explain the improvement in functional outcome. The functional recovery might more rely on the axonal regeneration and neuroprotective action that active by the grafted cells. Cografted HUMSCs and BDNF is a potential therapy for SCI. [ABSTRACT FROM AUTHOR]

The auxiliary equation method is very useful for finding the exact solutions of the nonlinear evolution equations. In this paper, a new idea of finding the exact solutions of the nonlinear evolution equations is introduced. The idea is that the exact solutions of the auxiliary elliptic-like equation are derived using exp-function method, and then the exact solutions of the nonlinear evolution equations are derived with the aid of auxiliary elliptic-like equation. As examples, the RKL models, the high-order nonlinear Schrödinger equation, the Hamilton amplitude equation, the generalized Hirota-Satsuma coupled KdV system and the generalized ZK-BBM equation are investigated and the exact solutions are presented using this method. [ABSTRACT FROM AUTHOR]

Through an Australia-China climate change bilateral project, we analyzed results of 51-year global offline simulations over China using the Australian community atmosphere biosphere land exchange (CABLE) model, focusing on integrated studies of its surface energy, water and carbon cycle at seasonal, interannual and longer time-scales. In addition to the similar features in surface climatology between the CABLE simulation and those derived from the global land-surface data assimilation system, comparison of surface fluxes at a CEOP reference site in northeast China also suggested that the seasonal cycles of surface evaporation and CO2 flux are reasonably simulated by the model. We further assessed temporal variations of model soil moisture with the observed variations at a number of locations in China. Observations show a soil moisture recharge–discharge mechanism on a seasonal time scale in central-east China, with soil moisture being recharged during its summer wet season, retained in its winter due to low evaporation demand, and depleted during early spring when the land warms up. Such a seasonal cycle is shown at both 50- and 100-cm soil depths in observations while the model only shows a similar feature in its lower soil layers with its upper layer soil moisture varying tightly with rainfall seasonal cycle. In the analysis of the model carbon cycle, the net primary productivity (NPP) has similar spatial patterns as the ones derived from an ecosystem model with remote sensing. The simulated interannual variations of NPP by CABLE are consistent with the results derived from remote sensing-based and process-based studies over the period of 1981–2000. Nevertheless an upward trend from observations is not presented in the model results. The model shows a downward trend primarily due to the constant CO2 concentration used in the experiment and a large increase of autotrophic respiration caused by an upward trend in surface temperature forcing data. Furthermore, we have compared river discharge data from the model experiments with observations in the Yangtze and Yellow River basins in China. In the Yangtze River basin, while the observed interannual variability is reasonably captured, the model significantly underestimates its river discharge, which is consist with its overestimation of evaporation in the region. In the Yellow River basin, the magnitudes of the river discharge is similar between modeled and observed but its variations are less skillfully captured as seen in the Yangtze River region. [ABSTRACT FROM AUTHOR]

The auxiliary equation method is very useful for finding the exact solutions of the nonlinear evolution equations. In this paper, a new idea of finding the exact solutions of the nonlinear evolution equations is introduced. The idea is that the exact solutions of the auxiliary elliptic-like equation are derived using exp-function method, and then the exact solutions of the nonlinear evolution equations are derived with the aid of auxiliary elliptic-like equation. As examples, the RKL models, the high-order nonlinear Schrödinger equation, the Hamilton amplitude equation, the generalized Hirota-Satsuma coupled KdV system and the generalized ZK-BBM equation are investigated and the exact solutions are presented using this method. [ABSTRACT FROM AUTHOR]

This study extends the analysis of the economic return of college education up to 10 years after college education and further examines the impact of college education on graduates’ hours of work. The results suggest that variation in hours of work explains a portion of earnings differentials among college graduates. Graduates from high-quality private institutions tend to work longer hours than their peers from other types of institutions. Female graduates spend fewer hours working than their male counterparts. As far as family background is concerned, graduates from high-income families tend to work longer hours and first-generation college graduates tend to work fewer hours. Finally, business majors seem to work longer hours while health and public affair majors less hours. [ABSTRACT FROM AUTHOR]

The rapid and accurate detection and identification of food-borne pathogenic bacteria is critical for food safety. In this paper, we describe a rapid (<4 h) high-throughput detection and identification system that uses universal polymerase chain reaction (PCR) primers to amplify a variable region of bacterial the 16S rRNA gene, followed by reverse hybridization of the products to species-specific oligonucleotide probes on a chip. This procedure was successful in discriminating 204 strains of bacteria from pure culture belonging to 13 genera of bacteria. When this method was applied directly to 115 strains of bacteria isolated from foods, 112/115 (97.4%) were correctly identified; two strains were indistinguishable due to weak signal, while one failed to produce a PCR product. The array was used to detect and successfully identify two strains of bacteria from food poisoning outbreak samples, giving results through hybridization that were identical to those obtained by traditional methods. The sensitivity of the microarray assay was 102 CFU of bacteria. Thus, the oligonucleotide microarray is a powerful tool for the detection and identification of pathogens from foods. [ABSTRACT FROM AUTHOR]

The forced vibration in the turning point frequency range of a truncated revolution shell subject to a membrane drive or a bending drive at its small end or large end is studied by applying the uniformly valid solutions obtained in a previous paper. The vibration shows a strong coupling between the membrane and bending solutions: either the membrane drive or the bending drive causes motions of both the membrane type and bending type. Three interesting effects characteristic of the forced vibration emerge from the coupling nature: the non-bending effect, the inner-quiescent effect and the inner-membrane-motion-and-outer-bending-motion effect. These effects may have potential applications in engineering. [ABSTRACT FROM AUTHOR]

A class of nonlinear Schrödinger-type equations, including the Rangwala-Rao equation, the Gerdjikov-Ivanov equation, the Chen-Lee-Lin equation and the Ablowitz-Ramani-Segur equation are investigated, and the exact solutions are derived with the aid of the homogeneous balance principle, and a set of subsidiary higher order ordinary differential equations (sub-ODEs for short). [ABSTRACT FROM AUTHOR]

Genetic algorithms (GAs) have gained wide research and applications in production scheduling fields, but the efficiency and effectiveness of a GA significantly depend on its parameters and operators. In contrast to the rich research on determination of optimal and adaptive parameters, little research has been done on determining optimal combination of genetic operators. Different from the traditional way by trial and error, this paper presents a novel and systematical approach based on ordinal optimisation (OO) and optimal computing budget allocation (OCBA) technique to determine optimal combination of genetic operators for flow shop scheduling problems. Simulation results show that the proposed methodology is able to determine optimal combination of genetic operators and simultaneously to provide a good solution with reasonable performance evaluation for scheduling problem. [ABSTRACT FROM AUTHOR]

This paper gives a sufficient and necessary condition for a bialgebra to be a Long bialgebra, and proves a braided product to be a Long bialgebra under some conditions. It also gives a direct sum decomposition of quantum Yang–Baxter modules over Long bialgebras. [ABSTRACT FROM AUTHOR]

Genetic algorithms (GAs) are a class of effective parallel searching algorithms inspired by the idea of “survival of the fittest”, which has been successfully applied to a variety of problems, especially in the fields of manufacturing and scheduling. However, it is reported that traditional GAs often suffer from the weaknesses of premature convergence as well as parameter and operator dependence. So far, many improved methods with adaptive parameters or hybrid structures have been proposed, but there is little literature considering the adaptive control of genetic operators. In this paper, an adaptive GA (AGA) with multiple operators is proposed for flowshop scheduling, which is a typical NP-hard optimisation problem with many industrial applications and has been widely studied in both academic and engineering fields. In AGA, multiple different genetic operators are employed in an adaptive hybrid way to enhance the exploration and exploitation abilities so as to prevent premature convergence and achieve superior performance. It especially important to stress that the utilising ratio of each operator for hybridisation is adaptively and dynamically controlled during the evolutionary searching process. Simulation results based on benchmarks demonstrate the effectiveness of AGA by contrast with traditional GAs. And the effect of the adaptive control of the operator and the effects of some parameters on the optimisation performance are discussed as well. [ABSTRACT FROM AUTHOR]

In this paper a new predictor-corrector noninterior method for LCP is presented, in which the predictor step is generated by the Levenberg-Marquadt method, which is new in the predictor-corrector type methods, and the corrector step is generated as in [3]. The method has the following merits: (i) any cluster point of the iteration sequence is a solution of the P0 LCP; (ii) if the generalized Jacobian is nonsingular at a solution point, then the whole sequence converges to the (unique) solution of the P0 LCP superlinearly; (iii) for the P0 LCP, if an accumulation point of the iteration sequence satisfies the strict complementary condition, then the whole sequence converges to this accumulation point superlinearly. Preliminary numerical experiments are reported to show the efficiency of the algorithm. [ABSTRACT FROM AUTHOR]

This paper examines the impact of college quality and academic major on the earnings of a nationally representative sample of baccalaureate recipients. We extend previous work in this area by analyzing the magnitude of change in the influence of these factors at two points in the early career of these graduates. Our results demonstrate that, despite significant variation, graduates from higher quality colleges enjoy a greater rate of growth in earnings during their early career. We also show that growth in earnings varies significantly by the graduates’ major field of study. Wage growth for women and racial minorities is also examined. [ABSTRACT FROM AUTHOR]

A transparent organic-inorganic epoxy/silica hybrid material was prepared by epoxy resin, functionalized-epoxy resin, which was partially functionalized by 3-aminopropyl triethoxylsilane(APTES), and highly reactive polysilcic acid (PSA), which was prepared through hydrolysis and condensation of metasilicate salt. The properties of hybrid materials such as impact strength, tensile strength, glass transition temperature (Tg), thermogravimetric temperature (TGA), and thermal effect of the hybrid materials were studied. The size of PSA particles in THF measured by dynamic light scattering technique, ranged from 10-28 nm. The results of experiment indicated that modified epoxy resin possed better roughness than that of the pure epoxy resin. The structure of the hybrid materials was characterized by FT-IR spectroscopy and 29SiNMR spectroscopy. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article on the use of the spinal magnetic resonance imaging (MRI) in children with Guillain-Barre syndrome (GBS).

A letter to the editor is presented in response to the article "The Prevalence of Headache May be Related With the Latitude: A Possible Role of Vitamin D Insufficiency?," by Sanjay Prakash et al. which appeared in a 2010 issue.

A letter to the editor in response to an article by P. Coto-Segura and colleagues regarding apolipoprotein allele and psoriasis published in a previous issue of the journal is presented.

We report a new type of memory device based on insulating LaAlO3/SrTiO3 (LAO/STO) hetero-interface. The microstructures of the LAO/STO interface are characterized by Cs-corrected scanning transmission electron microscopy, which reveals the element intermixing at the interface. The inhomogeneous element distribution may result in carrier localization, which is responsible for the insulating state. The insulating state of such interface can be converted to metallic state by light illumination and the metallic state maintains after light off due to giant persistent photoconductivity (PPC) effect. The on/off ratio between the PPC and the initial dark conductance is as large as 105. The metallic state also can be converted back to insulating state by applying gate voltage. Reversible and reproducible resistive switching makes LAO/STO interface promising as a nonvolatile memory. Our results deepen the understanding of PPC phenomenon in LAO/STO, and pave the way for the development of all-oxide electronics integrating information storage devices [ABSTRACT FROM AUTHOR]

Target prediction for animal microRNAs (miRNAs) has been hindered by the small number of verified targets available to evaluate the accuracy of predicted miRNA-target interactions. Recently, a dataset of 3,404 miRNA-associated mRNA transcripts was identified by immunoprecipitation of the RNA-induced silencing complex components AIN-1 and AIN-2. Our analysis of this AIN-IP dataset revealed enrichment for defining characteristics of functional miRNA-target interactions, including structural accessibility of target sequences, total free energy of miRNA-target hybridization and topology of base-pairing to the 5′ seed region of the miRNA. We used these enriched characteristics as the basis for a quantitative miRNA target prediction method, miRNA targets by weighting immunoprecipitation-enriched parameters (mirWIP), which optimizes sensitivity to verified miRNA-target interactions and specificity to the AIN-IP dataset. MirWIP can be used to capture all known conserved miRNA-mRNA target relationships in Caenorhabditis elegans at a lower false-positive rate than can the current standard methods. [ABSTRACT FROM AUTHOR]

Membrane-type 1 matrix metalloproteinase (MT1-MMP) is the most ubiquitous and widely studied of the membrane-type metalloproteinases (MT-MMPs). It was thus surprising to find no published data on chicken MT1-MMP. We report here the characterization of the chicken gene. Its low sequence identity with the MT1-MMP genes of other species, high GC content, and divergent catalytic domain explains the absence of data and our difficulties in characterizing the gene. The absence of structural features in the chicken gene that have been suggested to be critical for the activation of MMP-2 by MT1-MMP; for the effect of MT1-MMP on cell migration and for the recycling of MT1-MMP suggest these features are either not essential or that MT1-MMP does not perform these functions in chickens. Comparison of the expression of chicken MT1-MMP with MT3-MMP and with MMP-2 and MMP-13 has confirmed the previously recognized co-expression of MT1-MMP with MMP-2 and MMP-13 in fibrous and vascular tissues, particularly those surrounding the developing long bones in other species. By contrast, MT3-MMP expression differs markedly from that of MT1-MMP and of both MMP-2 and MMP-13. MT3-MMP is expressed by chondrocytes of the developing articular surface. Similar expression patterns of this group of MT-MMPs and MMPs have been observed in mouse embryos and suggest distinct and specific functions for MT1-MMP and MT3-MMP in skeletal development. [ABSTRACT FROM AUTHOR]

Cellulase genes have been reported not only from fungi, bacteria and plant, but also from some invertebrate animals. Here, two cellulase (endo-β-1,4-glucanase, EC 3.2.1.4) genes, eg27I and eg27II, were cloned from the freshwater snail Ampullaria crossean cDNA using degenerate primers. The nucleotide sequences of the two genes shared 94.5% identity. The open reading frames of both genes consisted of 588 bp, encoding 195 amino acids. Both EG27I and EG27II belong to the glycoside hydrolase family 45, and each lacks a carbohydrate-binding module. The presence of introns demonstrated a eukaryotic origin of the EG27 gene, and, in addition, successful cloning of EG27 cDNA supported endogenous production of EG27 cellulase by Ampullaria crossean. Investigation of the EG27 cDNA from A. crossean will provide further information on GHF45 cellulases. [ABSTRACT FROM AUTHOR]

Seismic deconvolution plays an important role in the seismic characterization of thin-layer structures and seismic resolution enhancement. However, the trace-by-trace processing strategy is applied and ignores the spatial connection along seismic traces, which gives the deconvolved result strong ambiguity and poor spatial continuity. To alleviate this issue, we developed a structurally constrained deconvolution algorithm. The proposed method extracts the reflection structure characterization from the raw seismic data and introduces it to the multichannel deconvolution algorithm as a spatial reflection regularization. Benefiting from the introduction of the reflection regularization, the proposed method enhances the stability and spatial continuity of conventional deconvolution methods. Synthetic and field data examples confirm the correctness and feasibility of the proposed method. [ABSTRACT FROM AUTHOR]

The reliability and accuracy of finite element models of metal machining are heavily reliant on the underlying material flow stress models. The aim of this study is to characterize the relation between the flow stress models and the chip morphology to provide a deeper insight into the process of serrated chip formation. Firstly, in the context of a flow stress model, the critical conditions for generation of the serrated chips are theoretically analyzed. Then, simulations are performed using two different constitutive models with five parameters sets, and the results are discussed in relation to how they verify the theoretical results. In order to better understand the process of serrated chip formation, attention is concentrated on the critical steps characterizing the formation of a single chip segment. The cutting process parameters (stress, strain, and temperature) are discussed. In addition, the mechanism by which the chip morphology transforms from continuous to serrated with increasing cutting speed is investigated in terms of the variation of flow stress curves. The results show that the slope of decrease and the strain value at the peak point of flow stress curves both greatly affect chip morphology. That is, the slope of decrease of the flow stress curve largely controls the formation of serrated chips, while the strain point at the peak determines the frequency and degree of serration of chips. It is found that simulations by manipulating well the flow stress models can produce results for chip morphology, cutting forces, etc. that are closer to those obtained experimentally. [ABSTRACT FROM AUTHOR]

In this work, the effects of reclaimed sand additions on the microstructure characteristics, mechanical properties and fracture behavior of furan no-bake resin sand have been investigated systematically within the temperature range from 25 to 600 °C. The addition of 20%-100% reclaimed sand showed dramatic strength deterioration effect at the same temperature, which is associated with the formation of bonding bridges. Both the ultimate tensile strength (UTS) and compressive strength (CS) of the moulding sand initially increase with the increase of temperature, and then sharply decrease with the further increase of temperature, which is attributed to the thermal decomposition of furan resin. The addition amount of reclaimed sand has a remarkable effect on the room temperature fracture mode, i.e., with the addition of 0-20% reclaimed sand, the fracture mode was mainly cohesive fracture; the fracture mode converts to be mixture fracture mode as the addition of reclaimed sand increases to 35%-70%; further increasing the addition to 100% results in the fracture mode of typical adhesive fracture. The fracture surface of the bonding bridge changes from a semblance of cotton or holes to smooth with the increase of test temperature. [ABSTRACT FROM AUTHOR]