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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]

Parkinson's disease (PD) is a progressive neurodegenerative disorder. Long non-coding RNA (lncRNA) XIST has been implicated in the development of PD. Herein, we sought to investigate the diagnostic value of serum XIST expression in PD. We recorded clinical baseline data, including age, sex, body mass index (BMI), years of education, and PD family history, for PD patients and healthy controls, in addition to the disease course in PD patients. The disease severity of PD patients was assessed using the Hoehn-Yahr grading scale. We evaluated serum XIST expression levels in PD patients and healthy controls using RT-qPCR and assessed the correlation between serum XIST expression and the Unified Parkinson's Disease Rating Scale (UPDRS) score. Additionally, we used receiver operating characteristic (ROC) curve to determine the diagnostic value of XIST expression for PD. Our results showed no significant differences in age, sex, BMI, and years of education between PD patients and healthy controls. However, more PD patients had a family history of PD. We found that serum XIST expression was significantly up-regulated in PD patients, and its levels were positively correlated with the UPDRS score. Higher PD stage was also associated with increased serum XIST expression. ROC analysis revealed that XIST expression had a diagnostic value for PD. In conclusion, our findings suggest that serum lncRNA XIST expression may serve as a potential diagnostic biomarker for PD. [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]

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]

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]

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]

Microsatellite markers are popular for assigning parentage, but single-nucleotide polymorphisms (SNPs) have only been applied in this area recently. To evaluate these two markers which have been previously studied in golden snub-nosed monkeys, we genotyped 12 individuals using 37 microsatellite loci and 37 SNP markers. The data showed that 32 of 37 microsatellite loci were polymorphic, and most microsatellite loci were high informative (mean PIC = 0.599). Meanwhile, 24 of 37 SNP markers were polymorphic and most were low informative (mean PIC = 0.244). For microsatellites, the combined exclusion probability with one-parent-unknown/known (CE-1P/CE-2P) nearly reached 1, while for the SNP markers, CE-2P only reached 0.9582. Under the condition of one parent known/unknown, the CE-2P and CE-1P could meet the international human parental standard (0.9973) by using five or nine microsatellite loci respectively. For SNP markers, we doubled the loci (n = 48) and simulated parentage testing, and the data showed that the CE-2P was 0.998 while the CE-1P was still low. This result indicated that the SNP loci which we used here had low polymorphism and that more loci need to be developed in the future. In addition, we corrected one case of failed identification by excluding siblings and reducing the range of candidate paternities. [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]

Laminated and sandwich joints composed of copper and 304 stainless steel with different stacking sequences were prepared by electron beam welding. The analysis of microstructures, element distribution and mechanical properties of the joints were carried out. Joints under all parameters were well formed without defects such as pores and cracks. The microstructures of the welds were mainly composed of (Cu, Fe) solid solution [(Cu, Fe)ss]. It was also found that the shear strength of the joint and the content of α-phase at the interface had a linear relationship. For laminated joints, the shear strength of steel/copper joint was increased by 12.7% compared with copper/steel joint, and the shear strength value reached 420 MPa. The scanning electron beam could refine microstructures and increase the weld width and improve the mechanical properties of the joints significantly. The tensile strength of the sandwich joint with steel as the intermediate layer was increased by 17.4% compared with the joint with copper as the intermediate layer. [ABSTRACT FROM AUTHOR]

Objective: To reveal the effect of foods with different natures on cold or hot syndrome and gastrointestinal bacterial community structure in mice. Methods: Forty-five 6-week-old male ICR Kunming mice of clean grade were divided into 5 groups, 9 per group, including the control (CK), hot nature herbs (HM), Hong Qu glutinous rice wine (RW), tea rice wine (TW), and cold nature herbs (CM) groups. Distilled water or corresponding herbs were administered to mice (0.01 mL/g body weight) in the 5 groups by gastric infusion respectively, once daily for 28 d. Appearance, behavior, and serum biochemical indicators, including 5-hydroxytryptamine (5-HT), thyroid stimulating hormone (TSH), noradrenaline (NE), cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP), the hot nature index, as well as the gastrointestinal bacterial community structure were analyzed in all groups after treatment. Results: After supplementation for 28 d, CM and TW mice showed different degrees of cold syndrome, and HM and RW mice showed different degrees of hot syndrome. Compared with the HM and RW mice, the TSH, NE, cAMP levels and hot nature indices in the CM and TW mice were significantly decreased and 5-HT and cGMP levels were significantly increased (P<0.05). There was no obvious change in appearance or behavior in CK mice. Results of clustering analysis showed that the gastrointestinal bacterial community structures were highly similar in TW and CM mice as well as in RW and HM mice, and that they were from the same branch, respectively, when the distance was 0.02. The key microbes associated with cold syndrome were Lachnospiraceae uncultured, Lactococcus, etc., and the key microbes associated with hot syndrome were S24-7 norank, Ruminococcaceae uncultured, etc. Conclusion: The interventions with different nature foods could change cold or hot syndrome in mice, leading to changes in gastrointestinal bacterial community structure. [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 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]

Double-layered graphene sheets (DLGSs) can be applied to the development of a new generation of nanomechanical sensors due to their unique physical properties. A rectangular DLGS with a nanoparticle randomly located in the upper sheet is modeled as two nonlocal Kirchhoff plates connected by van der Waals forces. The Galerkin strip transfer function method which is a semi-analytical method is developed to compute the natural frequencies of the massplate vibrating system. It can give exact closed-form solutions along the longitudinal direction of the strip. The results obtained from the semi-analytical method are compared with the previous ones, and the differences between the single-layered graphene sheet (SLGS) and the DLGS mass sensors are also investigated. The results demonstrate the similarity of the in-phase mode between the SLGS and DLGS mass sensors. The sensitivity of the DLGS mass sensor can be increased by decreasing the nonlocal parameter, moving the attached nanoparticle closer to the DLGS center and making the DLGS smaller. These conclusions are helpful for the design and application of graphene-sheet-based resonators as nano-mass sensors. [ABSTRACT FROM AUTHOR]

The effect of mold temperature on microstructure and mechanical properties of a rheo-squeeze casting (RSC) Mg--3Nd--0.2Zn--0.4Zr (NZ30K) alloy were investigated. The results indicated that the rise of mold temperature contributed to the increase of particle size and alloy density and the decrease of dislocation density. The rapid coarsening and then the normal growth of the particles during solution treatment were observed, and the long-rod-like Zn2Zr3 phase occurred. After age treatment, rod-like b9 precipitate was found in the conventional squeeze casting (CSC) alloy, while two types of precipitates including b9 phase and small plate-like b0 phase were observed in the RSC alloy. The amount of Zn2Zr3 phase was increased with rising mold temperature. Compared with the T6-treated CSC sample, the T6-treated RSC sample presented higher mechanical properties due to the larger precipitation strengthening contribution, and the yield strength, ultimate tensile strength, and elongation were up to 160 MPa, 296 MPa, and 7.7%. [ABSTRACT FROM AUTHOR]

Autophagy is a degradative pathway that delivers cellular components to the lysosome for degradation. The role of autophagy in cell differentiation is poorly understood. Here we show that CaMKII can directly phosphorylate Beclin 1 at Ser90 to promote K63-linked ubiquitination of Beclin 1 and activation of autophagy. Meanwhile, CaMKII can also promote K63-linked ubiquitination of inhibitor of differentiation 1/2 (Id-1/2) by catalyzing phosphorylation of Id proteins and recruiting TRAF-6. Ubiquitinated Id-1/Id-2 can then bind to p62 and be transported to autolysosomes for degradation. Id degradation promotes the differentiation of neuroblastoma cells and reduces the proportion of stem-like cells. Our study proposes a mechanism by which autophagic degradation of Id proteins can regulate cell differentiation. This suggests that targeting of CaMKII and the regulation of autophagic degradation of Id may be an effective therapeutic strategy to induce cell differentiation in neuroblastoma. [ABSTRACT FROM AUTHOR]

Mg–3.0Y–2.5Nd–1.0Gd–xZn–0.5Zr (x 5 0, 0.2, 0.5, and 1.0) (wt%) alloys were produced by metallic and sand mold casting to study the microstructure and mechanical properties of the alloys. The as-cast Zn-free alloys consist of a-Mg and eutectics, whereas the Zn-containing alloys contain additional long-period stacking ordered (LPSO) structures. With a higher solidification, the cooling rate brought by metallic mold casting, grains, and eutectics are refined, which enhances the elongation of the alloys, accompanied by a decrease of area fraction of the LPSO structure. Some residual eutectics in the Mg–3.0Y–2.5Nd–1.0Gd–1.0Zn–0.5Zr alloys act as obstacles to grain boundary migration during solution treatment, which make the average grain size 15–20 lm smaller than that of the other alloys and hence improve the elongation of the alloys. The Zn addition brings notable enhancements to mechanical properties of the alloys due to solid solution strengthening of Zn. Especially, the peak-aged Mg–3.0Y–2.5Nd–1.0Gd–0.5Zn–0.5Zr alloys perform with the highest overall tensile properties. [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]

To study the influence of the pantograph fixing position on aerodynamic characteristics of high-speed trains, the aerodynamic models of high-speed trains with eight cars were established based on the theory of computational fluid dynamics, and eight cases with pantographs fixed on different positions and in different operational orientations were considered. The pantographs were fixed on the front or the rear end of the first middle car or fixed on the front or the rear end of the last middle car. The external flow fields of the high-speed trains were numerically simulated using the software STAR-CCM+. The results show that the pantograph fixing position has little effect on the aerodynamic drag force of the head car and has a large effect on the aerodynamic drag force of the tail car. The influences of the pantograph fixing position on the aerodynamic lift forces of the head car, tail car and pantographs are obvious. Among the eight cases, considering the total aerodynamic drag force of the train and the aerodynamic lift force of the lifted pantograph, when the pantographs are fixed on the rear end of the last middle car and the lifted pantograph is in the knuckle-upstream orientation, the aerodynamic performance of the high-speed train is the best. [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]

The effect of solution treatment (ST) on the microstructure and mechanical properties of cast Al-3Li-1.5Cu-0.2Zr alloy was investigated. Results showed that the volume fraction of secondary phases (Al2Cu, Al3Li) decreased obviously after ST. It was found that the strengthening of Al-3Li-1.5Cu-0.2Zr alloy was a balance of the precipitation strengthening, residual phase strengthening and fine grain strengthening. The residual phase strengthening and fine grain strengthening decreased with increasing the solution temperature and time, while precipitation strengthening increased. After ST at 560 °C for 40 h, the elongation of Al-3Li-1.5Cu-0.2Zr alloy reaches the highest value of 22.1%. In addition, the tensile properties are up to the highest values, ultimate tensile strength of 359 MPa and elongation of 3.5% after optimal ST at 560 °C for 40 h followed by aging treatment. [ABSTRACT FROM AUTHOR]

In this paper, a method is proposed to improve the energy efficiency of the vertical axis turbine. First of all, a single disk multiple stream-tube model is used to calculate individual fitness. Genetic algorithm is adopted to optimize blade pitch motion of vertical axis turbine with the maximum energy efficiency being selected as the optimization objective. Then, a particular data processing method is proposed, fitting the result data into a cosine-like curve. After that, a general formula calculating the blade motion is developed. Finally, CFD simulation is used to validate the blade pitch motion formula. The results show that the turbine's energy efficiency becomes higher after the optimization of blade pitch motion; compared with the fixed pitch turbine, the efficiency of variable-pitch turbine is significantly improved by the active blade pitch control; the energy efficiency declines gradually with the growth of speed ratio; besides, compactness has lager effect on the blade motion while the number of blades has little effect on it. [ABSTRACT FROM AUTHOR]

Riparian buffer zones adjacent to reservoirs and lakes protect aquatic ecosystems from polluted surface runoff. Sediments, collected from the buffer zones of Danjiangkou Reservoir (SR) and Honghu Lake (SL) in an ecologically fragile region in central China, were evaluated to reveal their phosphorus-adsorbing/desorbing properties and storage capacities. A nonlinear regression method was used to fit the pseudo-second-order kinetic and the modified crossover-type Langmuir isotherm models to the experimental data. It is shown that the adsorption of phosphorus onto the studied sediments followed the pseudo-second-order kinetic expression. The modified crossover-type Langmuir isotherm model was found to be a suitable method for describing adsorption/desorption processes in the experimental sediments. The maximum adsorption capacities (Qm), partitioning coefficients (Kp), native adsorbed exchangeable phosphorus (NAP), and equilibrium phosphorus concentration (EPC0) were subsequently obtained for the experimental sediments. The effects of sediment concentration and pH were also investigated by batch experiments and Fourier transformation infrared and scanning electron microscopy analyses. The adsorption/desorption characteristics of different phosphate species on the sediments from reservoir and lake buffer zones were identified. [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]

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]

Purpose: The development of the human embryonic spinal cord is very complicated, and many cell types are involved in the process. However, the morphological characteristics of neuronal and glial cells during the development of the human fetal spinal cord have not been described. We investigated the systemic distributions and expression pattern of the cell type-specific markers Neuron-specific nuclear protein (NeuN) and glial fibrillary acidic protein (GFAP) during the development of the human fetal spinal cord, in order to clarify the detailed developmental changes of neuronal and glial cells in chronological and spatial aspects. Methods: A total of 35 fetuses, aged 3 weeks to 8 months of gestation (E3W-E8M), were studied. The markers used for immunohistochemical study were NeuN and GFAP. Results: The intracellular makers NeuN and GFAP were widely detected expression in different structures and cells during the development of the human fetal spinal cord, including the following: central canal, neuroepithelial layer, internal limiting membrane, mantle layer, marginal layer, basal plate, alar plate, ependymal layer, gray matter, white matter, neuron, astrocytes, and nerve fibers. However, there was an absence of GFAP in astrocytes during early fetal spinal cord development until E9W, and the appearance of GFAP-positive reactivity was later than that of neurons. Conclusions: We consider that NeuN and GFAP can be used to identify neuronal and glial cells during the development of the human fetal spinal cord, and their distribution differs both chronologically and spatially. These characteristic expression patterns would give us a clue to better understand the developmental characteristics of the human spinal cord. [ABSTRACT FROM AUTHOR]

A reactive brain-computer interface using electroencephalography (EEG) relies on the classification of evoked ERP responses. As the trial-to-trial variation is evitable in EEG signals, it is a challenge to capture the consistent classification features distribution. Clustering EEG trials with similar features and utilizing a specific classifier adjusted to each cluster can improve EEG classification. In this paper, instead of measuring the similarity of ERP features, the brain states during image stimuli presentation that evoked N1 responses were used to group EEG trials. The correlation between momentary phases of pre-stimulus EEG oscillations and N1 amplitudes was analyzed. The results demonstrated that the phases of time-frequency points about 5.3 Hz and 0.3 s before the stimulus onset have significant effect on the ERP classification accuracy. Our findings revealed that N1 components in ERP fluctuated with momentary phases of EEG. We also further studied the influence of pre-stimulus momentary phases on classification of N1 features. Results showed that linear classifiers demonstrated outstanding classification performance when training and testing trials have close momentary phases. Therefore, this gave us a new direction to improve EEG classification by grouping EEG trials with similar pre-stimulus phases and using each to train unit classifiers respectively. [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]

High-quality protein crystals of suitable size are an important prerequisite for applying X-ray crystallography to determine the 3-dimensional structure of proteins. However, it is often difficult to obtain protein crystals of appropriate size and quality because nucleation and growth processes can be unsuccessful. Here, we show that by adsorbing proteins onto porous polystyrene-divinylbenzene microspheres (SDB) floating on the surface of the crystallisation solution, a localised high supersaturation region at the surface of the microspheres and a low supersaturation region below the microspheres can coexist in a single solution. The crystals will easily nucleate in the region of high supersaturation, but when they grow to a certain size, they will sediment to the region of low supersaturation and continue to grow. In this way, the probability of crystallisation and crystal quality can be simultaneously increased in a single solution without changing other crystallisation parameters. [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]

The yellow dwarf disease associated with phytoplasmas is one of the most devastating diseases of mulberry and the pathogenesis involved in the disease is poorly understood. To analyze the molecular mechanisms mediating gene expression in mulberry-phytoplasma interaction, the comprehensive sRNA changes of mulberry leaf in response to phytoplasma-infection were examined. A total of 164 conserved miRNAs and 23 novel miRNAs were identified, and 62 conserved miRNAs and 13 novel miRNAs were found to be involved in the response to phytoplasma-infection. Meanwhile, target genes of the responsive miRNAs were identified by sequencing of the degradome library. In addition, the endogenous siRNAs were sequenced, and their expression profiles were characterized. Interestingly, we found that phytoplasma infection induced the accumulation of mul-miR393-5p which was resulted from the increased transcription ofMulMIR393A, and mul-miR393-5p most likely initiate the biogenesis of siRNAs from TIR1 transcript. Based on the results, we can conclude that phytoplasma-responsive sRNAs modulate multiple hormone pathways and play crucial roles in the regulation of development and metabolism. These responsive sRNAs may work cooperatively in the response to phytoplasma-infection and be responsible for some symptoms in the infected plants. [ABSTRACT FROM AUTHOR]

The development of atherosclerosis (AS) is a multifactorial process, in which elevated plasma resistin (a key factor leading to insulin resistance) levels play an important role. Emerging evidence indicate that microRNAs (miRNAs) are involved in AS; However, the regulation and function of miRNAs in response to AS remain poorly understood. Our study analyzed the effects of miR-492 on insulin resistance, endothelial activation, and resistin expression in apoE knock-out mice and human umbilical vein endothelial cells after high-glucose treatment and miR-492 mimics transfection. We also investigated the underlying molecular mechanisms. Our results showed that high glucose stress induced a significant decrease in miR-492 expression, with a remarkable upregulation of resistin expression. We then identified resistin as a novel direct target of miR-492 using 3′-UTR luciferase reporter assay. Histopathologic examination demonstrated that upregulation of miR-492 attenuated endothelial cells migration and lipid accumulation induced by high glucose stress. Further investigation demonstrated that the upregulation of p-STAT3, SOCS, and P-selectin activation induced by high glucose stress was attenuated by upregulation of miR-492. Together, our findings indicate that miR-492 contributes to insulin resistance and endothelial dysfunction induced by high glucose, via directly downregulating resistin expression, and involving STAT3 phosphorylation, SOCS, and P-selectin activation. [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]

The proximal malignant obstructive jaundice remains one of the most challenging problems for hepato-biliary surgeons. Particularly when the findings preclude surgical resection at exploration, the next decision seems hard to make. A novel palliative treatment called 'hepato-biliary-enteric stent drainage' was designed for these proximal malignant obstructive jaundice patients. Hepato-biliary-enteric stent drainage was performed with silicone tube whose diameter was determined according to the degree of dilated biliary ducts, and the proximal end of the tube was placed to intrahepatic ducts as far as possible, the distal end was placed across the duodenal papilla. Between February 2011 and August 2012, 23 patients with the proximal malignant obstructive jaundice of unresectable tumors at exploration received hepato-biliary-enteric stent drainage. Patient's liver function results, symptoms, complications, and survival time were documented. The bilirubin levels of all 23 patients had a considerable and persistent decrease after operation and remained low or normal before death except for four cases of recurrent jaundice (two resulted from migration of tube and other two resulted from hepatocellular carcinoma extensively involving liver parenchyma). After effective drainage, clinical symptoms of cholangitis such as fever or pain were markedly relieved. No procedure-related bleeding, bile leakage, pancreatitis were observed. The median survival time was 212 days, half-year and 1-year survival rate were 56.5 and 21.7 %, respectively. Hepato-biliary-enteric stent drainage with less expense, less complications, and easy operation may be an ideal option for patients with unresectable malignancy in the hilar region at exploration. [ABSTRACT FROM AUTHOR]

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]

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]

We present a complete framework for synthesizing style-preserving 2D cartoons by learning from traditional Chinese cartoons. In contrast to reusing-based approaches which rely on rearranging or retrieving existing cartoon sequences, we aim to generate stylized cartoons with the idea of style factorization. Specifically, starting with 2D skeleton features of cartoon characters extracted by an improved rotoscoping system, we present a non-negative style factorization (NNSF) algorithm to obtain style basis and weights and simultaneously preserve class separability. Thus, factorized style basis can be combined with heterogeneous weights to re-synthesize style-preserving features, and then these features are used as the driving source in the character reshaping process via our proposed subkey-driving strategy. Extensive experiments and examples demonstrate the effectiveness of the proposed framework. [ABSTRACT FROM AUTHOR]

Recently the ATP-binding cassette (ABC) efflux pumps have been proved to be a major component of drug resistance in Mycobacterium tuberculosis. The objective of this study was to investigate the expression profiles of Rv1456c-Rv1457c-Rv1458c efflux system in clinical isolates of M. tuberculosis and its involvement in drug-resistance mechanisms. Significantly increased mRNA expression of Rv1456c, Rv1457c, and Rv1458c appeared among the clinical isolates ( P < 0.05), which are resistant to at least one of the four first-line drugs including rifampin, isoniazid, streptomycin, and ethambutol. In addition, overexpression of this efflux system was more frequently found in multidrug-resistant and extensively drug-resistant M. tuberculosis strains. Therefore, Rv1456c-Rv1457c-Rv1458c efflux pumps may play an important role in drug resistance of treatment of M. tuberculosis. Further investigation of this gene may lead to the development of countermeasures against M. tuberculosis drug resistance. [ABSTRACT FROM AUTHOR]

Effects of trace amount of rare earth element Pr on properties and microstructure of Sn-0.7Cu-0.05Ni solder were investigated in this paper. The solderability of Sn-Cu-Ni-xPr alloy and shear strengh of Sn-Cu-Ni-xPr soldered micro-joints were determined by means of the wetting balance method and shear test, respectively. Moreover, microstructure of solder alloys bearing Pr, as well as intermetallic compound (IMC) layer formed at solder/Cu interface after soldering were observed. It was concluded that the major benefits of rare earth element Pr on Sn-Cu-Ni lead-free solder are: improving solderability, refining microstructure, and depressing IMC (IMC) growth, which exhibited improved mechanical properties. It also revealed that (Cu,Ni)Sn is the majority IMC phase at the interface of Sn-Cu-Ni-xPr/Cu solder joints. Ni added into the solder effectively suppressed the growth of CuSn and consequently also the total IMC layer thickness. Above all, the thickness and morphology of the interfacial (Cu,Ni)Sn IMC were optimized due to alloying Pr. It can be inferred that Pr and Ni would play an important role in improving the reliability of Sn-Cu-Ni lead-free solder joints. [ABSTRACT FROM AUTHOR]

To increase ethanol yield and decrease glycerol production in Saccharomyces cerevisiae, the strategies of direct cofactor-regulation were explored. During anaerobic batch fermentations, the yeast expressing Bacillus cereus gapN gene, encoding non-phosphorylating NADP-dependent glyceraldehyde-3-phosphate dehydrognease, produced 73.8 g ethanol l, corresponding to 96% of theoretical maximum yield compared to 92% for the wild type. The yeast expressing Escherichia coli frdA gene encoding the NAD-dependent fumarate reductase, exhibited a 22% (relative to the amount of substrate consumed) increase in glycerol yield in medium containing 2 g fumarate l. The yeast expressing mhpF gene, encoding acetylating NAD-dependent acetaldehyde dehydrogenase, produced 74.5 g ethanol l, corresponding to 97.4% of theoretical maximum yield while glycerol decreased by 40% when acetic acid was added before inoculation. This strain represents a promising alternative for ethanol production with lignocellulosic hydrolysates where acetate is available at significant amounts. [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]

Nowadays, a major concern of Sn-Cu based solder alloy today is focused on continuously improving the comprehensive properties of the solder joints formed between the solders and substrates. The key issues and improvements about Sn-Cu-X (X = Ni, rare earths, Zn, Co, Ga, In, Bi, secondary particles etc.) solder are outlined and evaluated in this paper which compared to Sn-Cu solder. It can be summarized that by adding appropriate amounts of certain alloying elements X to Sn-Cu solder, and it is possible to tailor the properties of the solder, such as the melting and solidification behaviors, wettability, microstructure, interfacial reactions and mechanical properties of the solder. The reliability issues related to the implementation of Sn-Cu-X solder in advanced electronics system are also introduced, which indicates that further development on the Sn-Cu-X solders are to be underway. [ABSTRACT FROM AUTHOR]