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It is important to improve the comprehensive performance of the ductile iron bars (DIBs) for the cylinder block of the extra high pressure hydraulic plunger pump and accelerate the industrial application. In this work, the LZQT600-3 DIBs with the diameter of 145 mm were prepared by the horizontal continuous casting (HCC) process, that is, LZQT600-3 HCCDIBs. The microstructure and room temperature tensile properties of different sections [left-edge (surface layer), left-1/2R (left half of the radius), and the center of the HCCDIBs] were studied. The results show that the spheroidization of LZQT600-3 HCCDIBs matrix from the left-edge, left-1/2R to the center is at nodulizing grade II and above. As the cooling rate gradually decreases from surface to the center of the HCCIBs, the number of spheroidized graphite is gradually reduced, the size is gradually increased, the shape factor is decreased, and the pearlite content and lamellate spacing are increased. Along the horizontal direction of the section, the hardness of the material is distributed symmetrically around the center of the HCCDIBs. In the vertical direction, the hardness distribution in the center of the HCCDIBs is asymmetrical due to the gravity during the solidification process. Therefore, the microstructure in the lower part of the section solidifies relatively quickly. The left-edge has the best tensile mechanical properties, and the ultimate tensile strength, yield tensile strength and elongation are 597.3 MPa, 418.5 MPa and 9.6%, respectively. The tensile fracture belongs to the ductile-brittle hybrid fracture. The comprehensive performances of LZQT600-3 HCCDIBs meet the actual application requirements of ultra-high pressure hydraulic plunger pump cylinder.

Amuc_1100 is a membrane protein from Akkermansia muciniphila, which has been found to play a role in host immunological homeostasis in the gastrointestinal tract by activating TLR2 and TLR4. In this study we investigated the effects and underlying mechanisms of Amuc_1100 on acute pancreatitis (AP) induced in mice by intraperitoneal injection of caerulein and lipopolysaccharide (LPS). The mice were treated with the protein Amuc_1100 (3 μg, i.g.) for 20 days before caerulein injection. Cecal contents of the mice were collected for 16S rRNA sequencing. We found that pretreatment with Amuc_1100 significantly alleviated AP-associated pancreatic injury, reduced serum amylase and lipase. Amuc_1100 pretreatment significantly inhibited the expression of proinflammatory cytokines (TNF-α, IL-1β, IFN-γ and IL-6) in spleen and pancreas through inhibiting NF-κB signaling pathway. Moreover, Amuc_1100 pretreatment significantly decreased the inflammatory infiltration, accompanied by the reduction of Ly6C+macrophages and neutrophils in the spleen of AP mice. Gut microbiome analysis showed that the abundance of Bacteroidetes, Proteobacteria, Desulfobacterotaand Campilobacterotawas decreased, while the proportion of Firmicutesand Actinobacteriotawas increased in AP mice pretreated with Amuc_1100. We further demonstrated that Amuc_1100 pretreatment restored the enrichment of tryptophan metabolism, which was mediated by intestinal flora. These results provide new evidence that Amuc_1100 lessens the severity of AP through its anti-inflammatory properties with a reduction of macrophages and neutrophil infiltration, as well as its regulation of the composition of intestinal flora and tryptophan metabolism.

Electrocatalytic hydrogenation (ECH) approaches under ambient temperature and pressure offer significant potential advantages over thermal hydrogenation processes but require highly active and efficient hydrogenation electrocatalysts. The performance of such hydrogenation electrocatalysts strongly depends not only on the active phase but also on the architecture and surface chemistry of the support material. Herein, Pd nanoparticles supported on a nickel metal–organic framework (MOF), Ni-MOF-74, are prepared, and their activity toward the ECH of benzaldehyde (BZH) in a 3 M acetate (pH 5.2) aqueous electrolyte is explored. An outstanding ECH rate up to 283 μmol cm–2h–1with a Faradaic efficiency (FE) of 76% is reached. Besides, higher FEs of up to 96% are achieved using a step-function voltage. Materials Studio and density functional theory calculations show these outstanding performances to be associated with the Ni-MOF support that promotes H-bond formation, facilitates water desorption, and induces favorable tilted BZH adsorption on the surface of the Pd nanoparticles. In this configuration, BZH is bonded to the Pd surface by the carbonyl group rather than through the aromatic ring, thus reducing the energy barriers of the elemental reaction steps and increasing the overall reaction efficiency.

In Taiwan, lung cancers occur predominantly in never-smokers, of whom nearly 60% have stage IV disease at diagnosis. We aimed to assess the efficacy of low-dose CT (LDCT) screening among never-smokers, who had other risk factors for lung cancer.

We report a convergent and efficient total synthesis of the C-norD-homosteroidal alkaloid (+)-heilonine with a hexacyclic ring system, nine stereocenters, and a trans-hydrindane moiety. Our synthesis features four selective C–H functionalizations to form key C–C bonds and stereocenters, a Stille carbonylative cross-coupling to connect the AB ring system with the DEF ring system, and a Nazarov cyclization to construct the five-membered C ring. These enabling transformations significantly reduced functional group manipulations and delivered (+)-heilonine in 11 or 13 longest linear sequence (LLS) steps.

This article considers an unmanned aerial vehicle-based hybrid dual-hop free-space optical (FSO)/underwater optical wireless communication (UOWC) system with a decode-and-forward relay, where the FSO channel is influenced by atmospheric loss, turbulence, pointing error, and angle-of-arrival fluctuation, and the UOWC channel is affected by oceanic path loss, turbulence, and pointing error. Using direct detection and heterodyne detection, we obtain tractable analytical expressions of the outage probability (OP) and bit error rate (BER), respectively. We then derive asymptotic bounds of the OP and BER to reveal more insights into the effects of various parameters. As an extension, we also analyze the system performance over a more general channel model. After that, we consider a serial multirelay-based hybrid FSO/UOWC system, and jointly optimize the relay number and the relay distance vector to obtain a tradeoff between system cost and OP performance. Numerical results are provided to validate the accuracy of the derivations and the superiority of the proposed optimization scheme. We also discuss the influences of various parameters on system performance.

This letter investigates the physical-layer security (PLS) of an indoor visible light communication system having a transmitter, a jammer, an intelligent reflecting mirror array (IRMA), a legitimate user, and an eavesdropper. Two scenarios are investigated for the non-negative input: one is having an average optical intensity constraint only, and the other is with both average and peak optical intensity constraints. By the entropy-power inequality and variational method, we derive closed-form expressions of secrecy-capacity lower bounds for the two scenarios, respectively. Based on the derived lower bound, we formulate a constrained secrecy-capacity maximization problem to further improve the PLS performance, and then transform it into a tractable problem by objective function approximation. After that, an optimization algorithm is proposed to solve the problem. Numerical results show the necessity of considering both IRMA and jammer, and also verify the effectiveness of the proposed algorithm.

For simplicity, most works on visible light communications (VLC) neglect the non-line-of-sight (NLoS) channel gain and the inter-symbol interference (ISI). This letter investigates the optimal and robust secure beamforming problems for multiple-input single-output VLC systems, where both the NLoS channel gain and ISI are considered. Under perfect channel state information (CSI), we formulate an optimal beamforming problem to maximize the secrecy rate under amplitude constraints on beamformers. The problem is shown to be nonconvex. We transform it into multiple tractable quasiconvex subproblems, and propose an iterative algorithm to solve it. To be more practical, we then consider the imperfect CSI and design the robust secure beamformers. Numerical results verify the efficiency of the proposed beamforming schemes. Moreover, it is also shown that the NLoS channel gain can improve the secrecy rate and well-designed beamformers can reverse the effect of ISI.

Pneumonia and bronchopneumonia are the most common infectious diseases in children. This study aimed to analyze changes in causative pathogens and antibiotic use for bronchopneumonia or pneumonia after the introduction of the 13-valent pneumococcal conjugate vaccine (PCV13) in children.

External contamination particles or wear particles corroded by a valve body are mixed into the fluid. As a result, when the fluid enters the fitting clearance of the valve core, it can cause an increase in resistance and lead to sticking failure of the valve core. This paper analyzes solid-liquid flow characteristics in fitting clearances and valve-core sticking based on the Euler-Euler model, using a typical hydraulic valve as an example. The impact of particle concentration and diameter on flow characteristics and valve-core sticking force was analyzed. The highest volume fraction of particles was in the pressure-equalizing groove (PEG), with peak values increasing as the particle diameter increased. The sticking force increased with increasing particle concentration. When the particle diameter was 12 µm, the sticking force was the largest, making this the sensitive particle diameter. Particle distribution and valve-core sticking force were compared for oval, rectangular, and triangular PEGs. The fluid-deflection angles in oval and rectangular PEGs were larger, and their values were 32.83° and 39.15°, respectively. The fluid-deflection angle in the triangular PEG was relatively small, less than 50% that of the oval or rectangular PEGs. The particle-volume-fraction peaks in oval, rectangular, and triangular PEGs were 0.0317, 0.0316, and 0.0312, respectively. The sticking forces of oval, rectangular, and triangular PEGs were 4.796, 4.802, and 4.757 N, respectively when the particle diameter was 12 µm. This work provides a reference for design and research aimed at reducing valve-core sticking.

In physical-layer security, secrecy capacity is an important performance metric. This work aims to determine the secrecy capacity for an indoor visible light communication system consisting of a transmitter, a legitimate receiver and an eavesdropping receiver. In such a system, both signal-independent noise and signal-dependent noise are considered. Under nonnegativity and average optical intensity constraints, lower and upper bounds on secrecy capacity are derived by the variational method, the dual expression of the secrecy capacity, and the concept of “the optimal input distribution that escapes to infinity”. By an asymptotic analysis at large optical intensity, there is a small gap between the asymptotic upper and lower bounds. Then, by adding a peak optical intensity constraint, we further analyze the exact and asymptotic secrecy-capacity bounds. For practical considerations, the effects of imperfect channel state information, multi-photodiode eavesdropper, and artificial noise on secrecy performance are also discussed. Finally, the derived secrecy-capacity bounds are verified by numerical results.

This letter focuses on an unmanned aerial vehicle (UAV)-based covert visible light communication system. In the system, the UAV (Alice) sends information to a legitimate user (Bob) covertly while avoiding being detected by a warden (Willie). We analyze the mutual information of the communication channel and the covertness constraint of the detection channel. To improve system performance, we optimize the UAV’s height by maximizing the mutual information between Alice and Bob under the UAV’s height constraint. Without considering the covertness constraint, we first obtain the optimal height of the UAV, and prove the existence and uniqueness of such an optimal height. Moreover, considering the covertness constraint, we obtain the covert optimal heights under different conditions according to the relationship between the UAV’s height and the covertness constraint, and verify the existence of the solutions. Finally, we verify the theoretical analysis by numerical results.

In recent years, nuclear magnetic resonance (NMR) logging has become increasingly prevalent in the characterization of rock properties such as porosity, permeability, saturation, and pore size distribution. However, interpreting such properties accurately from NMR logging data is challenging for some reservoirs. In particular, the impact of salinity, viscosity, and saturation on NMR measurements is not always clear, which can lead to inaccuracies in the resulting data interpretation. Properly accounting for these factors is essential in order to obtain accurate and reliable measurements for effective characterization of subsurface formations. This study utilized a random walk technique to simulate the NMR response of homogeneous sandstones using 3D CT images and conducted a sensitivity analysis under various salinity, crude oil viscosity, and water saturation conditions. The results indicate that the T2relaxation time slightly shifts toward the short relaxation direction as the salinity of the formation water increases. In addition, longer echo intervals result in a more significant forward shift in the T2value than shorter intervals. Whereas, for crude oil, the T2relaxation time becomes shorter as its viscosity increases. Furthermore, the effect of echo interval on the forward T2shift is less pronounced for crude oil than it is for formation water. Under water wet conditions, the T2spectrum of crude oil exhibits a peak at the volume relaxation position. As the water saturation decreases, the left two peaks in the T2spectrum shift toward shorter relaxation times. Under oil wet conditions, the T2spectrum exhibits a complex three-peak structure. The method provides a physical basis for interpreting NMR macroscopic responses, and the simulated NMR responses can help identify fluids in reservoirs.

Purpose: The Hard X-ray Modulation Telescope is China’s first X-ray astronomy satellite launched on June 15, 2017, dubbed Insight-HXMT. Active and passive thermal control measures are employed to keep devices at suitable temperatures. In this paper, we analyzed the on-orbit thermal monitoring data of the first 5 years and investigated the effect of thermal deformation on the point spread function (PSF) of the telescopes. Methods: We examined the data of the on-orbit temperatures measured using 157 thermistors placed on the collimators, detectors and their support structures and compared the results with the thermal control requirements. The thermal deformation was evaluated by the relative orientation of the two star sensors installed on the main support structure. Its effect was estimated with evolution of the PSF obtained with calibration scanning observations of the Crab nebula. Conclusion: The on-orbit temperatures met the thermal control requirements thus far, and the effect of thermal deformation on the PSF was negligible after the on-orbit pointing calibration.

Since 3D printed structure is conducted by the style of dimension reduction, the defects typically occur between the printing layers due to the poor rheological properties, which affects the durability most. This study focuses on exploring the durability of 3D printed calcium sulphoaluminate cement-based materials (CSACMs) with slag powder based on the correlation between printed structures and rheological parameters. Experimental results show that both the static and dynamic yield stress of 3D printed CSACMs exhibits a gradual increase with the slag powder content increases, while the thixotropy improves continually until reaching a maximum content at 15%. In this case, an increase in slag powder content leads to a significant reduction for structure deformation. However, poor printability occurs when the content of slag powder exceeds 15%. Besides, the chloride migration coefficient and maximum electric flux decreases from 7.28 × 10−12to 3.27 × 10−12 m2/s and 1347 to 711 K, respectively, when the content of slag powder increases from 0 to 10%. Meanwhile, the freezing resistance and linear shrinkage are improved. Based on the radar map correlation, structure deformation is significantly influenced by thixotropy, which is a crucial factor that can impact the durability of 3D printed CSACMs. In conclusion, the controllable rheology of 3D printed CSACMs are advantageous for improving the printed structures and durability.

Background Selenium (Se) plays a key role in controlling several processes in plant development, such as root growth and regulation of enzyme activity. However, research on the effects of Se in Sophora tonkinensis, a medicinal plant, has not been reported. To elucidate the effect of Se on the accumulation of secondary metabolites in tissue-cultured seedlings of S. tonkinensis.Materials and Methods Tissue culture seedlings of S. tonkinensiswas treated with different concentrations of Se in the rooting medium. Agronomic traits of roots and concentrations of hormones and some secondary metabolites were measured from seedlings.Results The results show that (1) root growth of tissue culture seedlings were stimulated by Se; (2) a specific amount of Se enhanced the activities of peroxidase (POD) and superoxide dismutase (SOD), as well as the production and storage of soluble proteins and chlorophyll; and (3) Se treatment lowered brassinolide (BR) content, and 15 mg/L Se minimized abscisic acid (ABA) content, while 60 mg/L Se enhanced ABA content. The gibberellin (GA3) content in seedlings increased significantly compared with the control under the treatment of 60 mg/L Se.Conclusion Se concentration of 30 mg/L facilitated matrine and oxymatrine production and accumulation in stem/leaf tissues.

In this study, coal tar-based phenolic foam (CPF) was prepared using low-temperature coal tar as raw material to partially replace phenol. The chemical structure, apparent morphology, compressive strength, thermal stability, flame retardancy and thermal insulation properties of CPFs were characterized. The results show that CPFs have similar chemical structures to conventional phenolic foam. Comparing with conventional phenolic foam, the compressive strength of 30%CPF and 40%CPF increases by 18.3% and 55.9%, and the pulverization rate decreases by 22.9% and 50.8%, respectively. The results indicated that toughness was significantly strengthened due to the incorporation of aliphatic structures such as alkylphenols. In addition, the thermal stability of CPFs in the low temperature stage also improves. Although the limited oxygen index of CPFs decreases and thermal conductivity of CPFs increases, they still maintain good flame retardancy and thermal insulation properties. The obtained results prove that low-temperature coal tar can significantly replace phenol to prepare phenolic foam with good performance, which provides a new idea for the high-value utilization of low-temperature coal tar.

Nontuberculous mycobacteria (NTM) may be present in the respiratory tract of patients with lung cancer. We investigated the association of pulmonary NTM with the clinical features and outcomes of patients with lung cancer.

Hot-rolled Al-Si alloy sheets are used to be formed Al alloy welding additions and cladding materials that are widely used in the aviation, automotive, and air conditioning industries. However, if parameters of hot-rolling process are not properly selected, porosity defects during casting will lead to cracks or fractures in Al-Si alloy sheets. This study based on meso-damage theory and established a damage equation describing porosity defects in the hot rolling process. The parameters of GTN (Gurson-Tvergaard-Needleman) void defect evolution, including the volume fraction of voids in different periods, the plastic equivalent variation of void nucleation, the standard variance of equivalent variation of void nucleation, and the correction coefficient of the material, are determined in this study. A finite element model of the porosity defects is developed based on the determined parameters. The finite element method is used to analyze the effect of different process parameters on the porosity defects and cracks in Al-Si alloy sheets during hot rolling, then we performed the hot rolling test to validate the results. The results show that the void stress and diameter are reduced and the quality of porosity defects is improved by decreasing rolling reductions and increasing the temperature. The optimized process parameters were a 20% depression and a temperature of 550°C.

A novel method based on periodic change of two-phase velocity for the droplet coalescence in microchannels is proposed. The feasibility of the method is justified by investigating the droplet coalescence in several combinations of the velocity pairs. Once the droplet pairs have been generated, the frequency of the droplet coalescence can be divided into a liquid slug of continuous phase dominated region and a real velocity ratio dominated region. Since the liquid slug between the droplet pairs and the real velocity ratio of the droplet pairs are determined by the flow rate ratios, the critical value of the flow rate ratio is determined to distinguish whether the frequency of the droplet coalescence is liquid slug dominated or real velocity ratio dominated. Compared with the traditional passive method, the droplet pairs are alternatively generated by the periodic change of the two-phase velocity. The velocity gradient of the droplet pairs can be generated spontaneously which avoids the introduction of an expansion structure. The mixing performance inside the coalesced droplet is improved due to the reorganized inner circulation when the droplets is coalesced. The quantitative mixing of the reagents can be achieved to satisfy special application needs by a precise control of the volume of the droplet pairs.

Urinary tract infections (UTIs) are the most common bacterial infection in young children. This study aimed to formulate nomogram plots for clinicians to predict UTIs in children aged <3 years by evaluating the risk factors for UTIs in these children.

Purpose: We present the five-year in-orbit background evolution of Insight-HXMT since the launch, as well as the effects of the background model in data analysis. Methods: The backgrounds of the three main payloads, i.e., low-energy telescope, medium-energy telescope, and high-energy telescope, are described. The evolution of the background over time is obtained by simply comparing the background in every year during the in-orbit operation of Insight-HXMT. Results: The major observational characteristics of the Insight-HXMT in-orbit background are presented, including the light curve, spectrum, geographical distribution, and long-term evolution. The systematic error in background estimation is investigated for every year. Conclusion: The observational characteristics of the five-year in-orbit background are consistent with our knowledge of the satellite design and the space environment, and the background model is still valid for the latest observations of Insight-HXMT.

A vector bending sensor based on hole-assisted three-core fiber (HATCF) Mach-Zehnder interferometer (MZI) is demonstrated. The sensor is composed of multi-mode fiber (MMF) - HATCF - MMF structure embedded between two single-mode fibers (SMFs). The bending curvature and direction can be identified by interrogating the wavelength of the interference peak, and the maximum bending sensitivity of −28.726 nm/ $\text{m}^{-1}$ is obtained at the 220° direction. In addition, the sensor has a temperature sensitivity of 44 pm/°C and is insensitive to the external refractive index (RI).

Lung cancer is the global leading cause of cancer death. Taiwan initiated several health policies including smoking cessation, precision therapy, and low-dose computed tomography (LDCT) screening in 1997. We aimed to investigate the effect of public policies on lung cancer survival.

In this study, the original basalt fiber (BF), and the sizing-removed BF through the heat treatment were pneumatically dispersed by using an air compressor and then were added into normal strength concrete to produce BF reinforced concrete (BFRC). The compressive test, splitting tensile test, and flexural test of BFRC specimens with two types of BF, three types of BF weight ratios, and three different BF lengths were performed. The test results show that the strength of sizing-removed BFRC specimens with 10‰ weight ratio was the highest compared to the other BFRC specimens. The sizing-removed BFRC specimens with 6 mm BF exhibit the maximum compressive strength, and sizing-removed BFRC specimens with 24 mm BF have the maximum splitting tensile strength and flexural strength. The sizing-removed BF with 10‰ weight ratio and three different types of fiber lengths were used in the impact test; the BFRC specimens with mixed 12 and 24 mm lengths have the best impact resistance performance compared to the BFRC specimens with fixed BF length. From SEM observation of the BFRC specimens after the impact test, the 24 mm BF in the BFRC specimen tends to breakage failure due to its higher bonding force.

In this study, droplet characteristics including droplet length and formation time, and mixing efficiency in droplets were investigated via the volume of fluid (VOF) method coupled with a user defined scalar (UDS) model. A cross-shaped junction with a square cross-section was designed and used for droplet formation. An initial arrangement which differed from that of a conventional operation was adopted. Results show that when the droplet superficial velocity is constant, the exchange between the dispersed phase velocity and the continuous phase velocity has a marginal effect on the droplet formation time. However, the exchange has a great effect on droplet length. These findings provide a valuable guide for future operation of droplet formation. In addition, the results show that the mixing efficiency in the droplet forming stage can be classified into time-dominated and length-dominated regimes according to the droplet superficial velocity. When a droplet flows in a microchannel, a higher droplet superficial velocity increases mixing efficiency due to the faster inner circulation and shorter droplet length.

This study aimed to evaluate whether vitamin D supplementation can reduce the incidence of influenza and enterovirus infection in Taiwanese children.

An ultrafast framing camera with a pulse-dilation device, a microchannel plate (MCP) imager, and an electronic imaging system were reported. The camera achieved a temporal resolution of 10 ps by using a pulse-dilation device and gated MCP imager, and a spatial resolution of 100 μm by using an electronic imaging system comprising combined magnetic lenses. The spatial resolution characteristics of the camera were studied both theoretically and experimentally. The results showed that the camera with combined magnetic lenses reduced the field curvature and acquired a larger working area. A working area with a diameter of 53 mm was created by applying four magnetic lenses to the camera. Furthermore, the camera was used to detect the X-rays produced by the laser-targeting device. The diagnostic results indicated that the width of the X-ray pulse was approximately 18 ps.

Active metal ions often show a strong cutting effect on the chemical bonds during high-temperature thermal processes. Herein, a one-pot metal ion cutting-assisted method was adopted to design defect-rich MoS2–xnanosheet (NS)/ZnS nanoparticle (NP) heterojunction composites on carbon nanofiber skeletons (CNF@MoS2–x/ZnS) via a simple Ar-ambience annealing. Results show that Zn2+ions capture S2–ions from MoS2and form into ZnS NPs, and the MoS2NSs lose S2–ions and become MoS2–xones. As sulfur hosts for lithium–sulfur batteries (LSBs), the CNF@MoS2–x/ZnS–S cathodes deliver a high reversible capacity of 1233 mA h g–1at 0.1 C and keep 944 mA h g–1at 3 C. Moreover, the cathodes also show an extremely low decay rate of 0.012% for 900 cycles at 2 C. Series of analysis indicate that the MoS2–xNSs significantly improve the chemisorption and catalyze the kinetic process of redox reactions of lithium polysulfides, and the heterojunctions between MoS2–xNSs and ZnS NPs further accelerate the transport of electrons and the diffusion of Li+ions. Besides, the CNF@MoS2–x/ZnS–S LSBs also show an ultralow self-discharge rate of 1.1% in voltage. This research would give some new insights for the design of defect-rich electrode materials for high-performance energy storage devices.

Thanks to its preparatory ease, close affinity, and low cost, the aptasensor can serve as a promising substitute for antibody-dependent biosensors. However, the available aptasensors are mostly subject to a single-mode readout and the interference of unbound aptamers in solution and non-target-induced transition events. Herein, we proposed a multimodal aptasensor for multimode detection of ochratoxin A (OTA) with cross-validation using the 3′-6-carboxyfluorescein (FAM)-enhanced exonuclease I (Exo I) tool and magnetic microbead carrier. Specifically, the 3′-FAM-labeled aptamer/biotinylated-cDNA hybrids were immobilized onto streptavidin-magnetic microbeads via streptavidin–biotin interaction. With the presence of OTA, an antiparallel G-quadruplex conformation was formed, protecting the 3′-FAM labels from Exo I digestion, and then anti-FAM-horseradish peroxidase (HRP) was bound via specific antigen-antibody affinity; for the aptamers without the protection of OTA, the distal ssDNA was hydrolyzed from 3′ → 5′, releasing 3′-FAM labels to the solution. Therefore, the OTA was detected by analyzing the “signal-off” fluorescence of the supernatant and two “signal-on” signals in electrochemistry and colorimetry through the detection of the coating magnetic microbeads in HRP’s substrate. The results showed that the 3′-FAM labels increased the activity of Exo I, producing a low background due to a more thorough digestion of unbound aptamers. The proposed multimodal aptasensor successfully detected the OTA in actual samples. This work first provides a novel strategy for the development of aptasensors with Exo I and 3′-FAM labels, broadening the application of aptamer in the multimode detection of small molecules.

The purpose of this study was to examine the in vivoactivity of rosmarinic acid (RA) – a phytochemical with antioxidant, anti-inflammatory, and antiviral properties – against influenza virus (IAV). An antibody-based kinase array and different in vitrofunctional assays were also applied to identify the mechanistic underpinnings by which RA may exert its anti-IAV activity.

The two-stage sleeve control valve has been widely implemented in the high-pressure difference hydraulic system, whose function is to reduce hydrodynamic noise. The sleeve with orifices plays a significant role in reducing the hydrodynamic noise. The ratio of orifices diameter between the outer sleeve and inner sleeve, Ri, is investigated in this paper. The coupling effect of Rion the flow field and hydrodynamic noise is analyzed deeply by URANS and FW-H model. Furthermore, the pressure, velocity, turbulent kinetic energy, and sound pressure level of the flow field are monitored. The results indicate that higher Riwill restrict the flow velocity in the orifices, and the distributed pressure drop of two sleeves will be even. The velocity of flow in the outer sleeve reduces from 130 m/s to 90 m/s with the increase of Ri. In addition, larger Rican reduce the hydrodynamic noise and obtain higher flow capacity. When the Riis 1.2, the sound power level distributes evenly in the gap, and the radiation intensity of the sound source is the smallest. The study can provide a reference for the design of sleeves in high-pressure control valves.

The charge valve is an important element in the charging port of a high-pressure hydrogen storage cylinder (HP-HSC). It is normally closed after the HP-HSC is filled with hydrogen. If the seal of the charge valve is damaged, it will seriously affect the stable operation of the hydrogen supply system and may even cause safety problems. Therefore, the seal performance of the charge valve is important. In this paper, finite element analysis (FEA) is carried out to analyze the seal contact performance of hydrogenated nitrile rubber (HNBR) gaskets in the seal pair of a charge valve. The effects of different pre-compressions, seal widths, and hydrogen pressures on the seal contact performance of the charge valve are analyzed. The contact pressure on the seal surface increases with the increase of pre-compression. With a pre-compression of 2.5 mm, the maximum contact pressure without and with hydrogen pressure are 68.51 and 107.38 MPa, respectively. A contact gap appears in the inner ring of the seal surface with pre-compression below 0.15 mm. The contact gap occurs between the entire seal surface with a seal width of 1 mm. The contact pressure on the seal surface and the width of the separation area between the seal surfaces increase with the increase of the seal width. The contact gap between the seal surfaces is zero with a width of 2.5 mm. The width of the separation area between the seal surfaces decreases with the decrease of the hydrogen pressure. The width of the separation area is reduced from 0.5 mm at 35 MPa to 0.17 mm at 15 MPa. This work can be useful for improvement of the seal performance and of the design of the charge valve used in the HP-HSC.

To facilitate the large-scale application of direct methanol fuel cells (DMFCs), the issue of low Pt/C durability due to Pt degradation and carbon corrosion in harsh DMFC operating conditions must be addressed. A promising strategy is to hybridize metal oxides with carbon materials, resulting in a durable and conductive support that exhibits a strong metal-support interaction (SMSI) effect on platinum nanoparticles (Pt NPs). In this study, we introduced a TiO2 coating on carbon black, creating a TiO2 nanolayer between Pt and carbon black. The nanolayer not only protects the carbon black but also activates the SMSI effect on Pt. The resulting Pt/C@TiO2 electrocatalyst exhibits superior durability than commercial Pt/C. After the accelerated durability test, the mass activity loss of the methanol oxidation reaction (MOR) of Pt/C@TiO2 (32%) is significantly lower than that of Pt/C (46.8%). Moreover, the MOR activity of Pt/C@TiO2 is higher than Pt/C as well. It suggests that Pt/C@TiO2 shows great potential as a highly durable and active electrocatalyst for DMFCs.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jtcvs.2005.06.012 Byline: Chen-Tu Wu (a), Yih-Leong Chang (a), Jin-Yuan Shih (b), Yung-Chie Lee (c) Abstract: Estrogen receptor expression in lung cancer has been understudied, particularly in light of its potential biologic importance in the epidemic of lung cancer in women. The expression of estrogen receptors was investigated to better understand the possible role of sex hormones in lung cancer. Author Affiliation: (a) Department of Pathology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan (b) Department of Internal Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan (c) Department of Surgery and Traumatology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan Article History: Received 15 February 2005; Revised 3 May 2005; Accepted 16 June 2005 Article Note: (footnote) Supported by National Science Council, ROC (NSC 92-2314-B-002-255 and NSC 93-2314-B-002-044).

Background: Tumor invasion and metastasis cause most deaths in cancer patients. Connective tissue growth factor (CTGF), a secreted protein that binds to integrins, modulates the invasive behavior of certain human cancer cells, but few mechanistic details are known. We investigated the roles of CTGF and collapsin response mediator protein 1 (CRMP-1) in metastasis and invasion of human lung adenocarcinoma. Methods: We compared vector control-transfected cells with corresponding CTGF gene-transfected cells. Invasive activity was measured with a modified Boyden chamber assay, and metastatic activity was measured in an animal model. We used CTGF deletion mutants, CTGF and CRMP-1 antisense oligonucleotides, and anti-integrin and anti-CRMP-1 antibodies to investigate the functional relationship between CTGF and CRMP-1. Expression of CTGF protein in 78 lung adenocarcinoma specimens was investigated immunohistochemically. All statistical tests were two-sided. Results: Invasive (both P

Feed-water valves (FWVs) are used to regulate the flow rate of water entering steam generators, which are very important devices in nuclear power plants. Due to the working environment of relatively high pressure and temperature, there is strength failure problem of valve body in some cases. Based on the thermo-fluid-solid coupling model, the valve body stress of the feed-water valve in the opening process is investigated. The flow field characteristics inside the valve and temperature change of the valve body with time are studied. The stress analysis of the valve body is carried out considering mechanical stress and thermal stress comprehensively. The results show that the area with relatively high-velocity area moves gradually from the bottom of the cross section to the top of the cross section with the increase of the opening degree. The whole valve body reaches the same temperature of 250 °C at the time of 1894 s. The maximum stress of the valve body meets the design requirements by stress assessment. This work can be referred for the design of FWVs and other similar valves.