Search

HfW2O8 thin films were grown on quartz substrates using a pulsed-laser deposition method at various temperatures from room temperature to 500°C and different oxygen pressures from 5Pa to 20Pa. The effects of substrate temperatures, oxygen pressures and post-annealing on the phase compositions and morphologies of the obtained HfW2O8 thin films were systematically investigated using X-ray diffraction (XRD) and a field emission scanning electron microscope (FESEM). The thermal expansion properties of the cubic HfW2O8 thin films were characterized using high temperature X-ray diffraction (HTXRD). Results indicate that the as-deposited HfW2O8 thin films show amorphous phases. Crystallized cubic HfW2O8 thin films can be prepared by heating at 1200°C for 7min. HfW2O8 thin film grown at 500°C with an oxygen pressure of 5Pa displayed the smoothest and uniform surface morphologies. The high temperature X-ray diffraction analyses demonstrate that the cubic HfW2O8 thin film exhibits strong negative thermal expansion and an α to β structure phase transition occurred between 100°C and 150°C. Its average linear thermal expansion coefficient was calculated to be -9.33×10-6 K-1 from 25°C to 600°C. [ABSTRACT FROM AUTHOR]

We study the uniaxial optical anisotropy of tetragonal BiFeO3 using first-principles density-functional theory and the Heyd-Scuseria-Ernzerhof hybrid functional in the near infrared to near ultraviolet range, and compare the results with related experiment and theory. It is found that the dielectric function is overall blue shifted compared with that of rhombohedral BiFeO3, and the charge transfer excitations are ~0.3 eV higher than those of the rhombohedral counterpart, which is caused by the symmetry breaking of FeO6 octahedral. Furthermore, it is a negative uniaxial crystal and shows significant birefringence. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) is toxic to plant cells. Under Cd exposure, the plant displayed leaf chlorosis, which is a typical symptom of iron (Fe) deficiency. Interactions of Cd with Fe have been reported. However, the molecular mechanisms of Cd-Fe interactions are not well understood. Here, we showed that FER-like Deficiency Induced Transcripition Factor (FIT), AtbHLH38, and AtbHLH39, three basic helix-loop-helix transcription factors involved in Fe homeostasis in plants, also play important roles in Cd tolerance. The gene expression analysis showed that the expression of FIT, AtbHLH38, and AtbHLH39 was up-regulated in the roots of plants treated with Cd. The plants overexpressing AtbHLH39 and double-overexpressing FIT/AtbHLH38 and FIT/ AtbHLH39 exhibited more tolerance to Cd exposure than wild type, whereas no Cd tolerance was observed in plants overexpressing either AtbHLH38 or FIT. Further analysis revealed that co-overexpression of FIT with AtbHLH38 or AtbHLH39 constitutively activated the expression of Heavy Metal Associated3 (HMA3), Metal Tolerance Protein3 (MTP3), Iron Regulated Transporter2 (IRT2), and Iron Regulated Gene2 (IREG2), which are involved in the heavy metal detoxification in Arabidopsis (AnTbidopis thaliana). Moreover, co-overexpression of FIT with AtbHLH38 or AtbHLH39 also enhanced the expression of NICOTIANAMINE SYNTHETASE1 (NAS1) and NAS2, resulting in the accumulation of nicotiananamine, a crucial chelator for Fe transportation and homeostasis. Finally, we showed that maintaining high Fe content in shoots under Cd exposure could alleviate the Cd toxicity. Our results provide new insight to understand the molecular mechanisms of Cd tolerance in plants. [ABSTRACT FROM AUTHOR]

The oxygen permeation of dense U-shaped perovskite hollow-fiber membranes based on BaSrCoFeO prepared by a phase inversion spinning process is reported. The perovskite hollow fibers with totally dense wall were obtained with the outer diameter of 1.147 mm and the inner diameter of 0.691 mm. The dependences of the oxygen permeation on the air flow rate on the shell side, the helium flow rate on the core side, the oxygen partial pressures, and the operating temperatures were experimentally investigated. According to the Wagner theory, it follows that the oxygen transport through the U-shaped hollow-fiber membrane is controlled by both surface reaction and bulk diffusion at the temperature ranges of 750-950°C. High oxygen permeation flux of 3.0 ml/(min cm) was kept for about 250 h at 950°C under the conditions of the air feed flow rate of 150 ml/min and the helium flow rate of 50 ml/min. © 2010 American Institute of Chemical Engineers AIChE J, 2011 [ABSTRACT FROM AUTHOR]

cold-adapted α-amylase ( ParAmy) gene from Pseudoalteromonas arctica GS230 was cloned, sequenced, and expressed as an N-terminus His-tag fusion protein in E. coli. A recombinant protein was produced and purified with DEAE-sepherose ion exchange chromatography and Ni affinity chromatography. The molecular weight of ParAmy was estimated to be 55 KDa with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). With an optimum temperature for activity 30 °C, ParAmy showed 34.5% of maximum activity at 0 °C and its activity decreased sharply at above 40 °C. ParAmy was stable in the range of pH 7-8.5 at 30 °C for 1 h. ParAmy was activated by Mn, K and Na, and inhibited by Hg, Cu, and Fe. N-Bromosuccinimid showed a significant repressive effect on enzyme activity. The K and V values of the α-amylase for soluble starch were 7.28 mg/mL and 13.07 mg/mL min, respectively. This research suggests that Paramy has a good potential to be a cold-stable and alkalitolerant amylase in detergent industry. [ABSTRACT FROM AUTHOR]

In this work, a series of ZrO2/ZrW2O8 ceramic composites with different amounts of ZrW2O8 were successfully prepared by calcining the precursors synthesized using co-precipitation route at 1150°C for 3 h. The X-ray diffraction (XRD) data confirmed that the composites only consisted of α-ZrW2O8 phase and m-ZrO2 phase. The scanning electron microscopy (SEM) analysis of the synthesized ZrO2/ZrW2O8 composites showed that the specimens had good mixed-uniformities. In addition, the thermal expansion coefficients of the composites decreased with increased amounts of negative thermal expansion ZrW2O8, specimen with 26wt% ZrW2O8 shows almost zero thermal expansion and its average thermal expansion coefficient is -0.5897×10-6K-1 in the temperature range from 30°C to 600°C. [ABSTRACT FROM AUTHOR]

Proposes an approach for obtaining the orientational angle of interfacial chemical groups. Basic relationship between the orientation angle and sum frequency generation vibrational spectroscopy intensity; Null angle method; Orientational angle of the methyl group of methanol orients from the surface normal at the air/methanol interface.

Purpose: To prepare azithromycin (AZI) sustained-release suspension containing AZI-coated microcapsules (AZI-CM) impregnated with AZI-drug resin complex (AZI-DRC), in order to mask the bitter taste of AZI and improve the oral compliance of patients. Methods: The AZI-DRC was prepared using the bath method, with cation exchanger resin Amberlite®IRP64 as a drug carrier, and it was characterized using scanning electron microscopy (SEM), x-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. Pretreated AZI-DRC was coated using emulsification-solvent evaporation method to achieve sustained-release effect. The effect of coating on in vitro drug release of the microcapsules was investigated to obtain the optimal AZI-CM through single-factor investigation. The optimized AZI-CM formulation was further dispersed in the optimized suspension matrix to obtain AZI sustained-release suspension. Then, the pharmacokinetics of AZI sustained release from the suspension was studied in rats and compared with commercially available AZI dry suspension. Results: Taste evaluation by volunteers showed that AZI-DRC had a good taste-masking effect on AZI. Results from SEM, XRD and FTIR demonstrated that AZI was present in AZI-DRC solely in amorphous form. Three batches of AZI-CM prepared after optimization produced a significant sustained release effect (p < 0.05). The AZI sustained-release suspension did not change significantly after 10 days and 3 months, indicating good stability (F > 0.9; drug release: f2 > 50; drug leakage < 0.5 %). In vivo results showed that AZI sustained-release suspension had a lower Cmax a higher Tmax and a better bioequivalence than AZI dry suspension available in the market. Conclusion: These findings depict a newly developed AZI sustained-release suspension with improved bioavailability, sustained-release effect, masked bitterness, and good therapeutic effect. [ABSTRACT FROM AUTHOR]

In the present study, we employed electrostatic spray technology to fabricate mesoporous microspheres containing sodium hyaluronate (SHMM). This approach aimed to overcome a significant challenge in the formulation development process, specifically addressing the limited water-locking ability inherent to the double-helix structure of sodium hyaluronate (SH). Various parameters were systematically investigated, including the solvent employed, concentrations of SH and poly (ethylene oxide), electrospray flow rate, voltage settings, and needle diameter. Through systematic single-factor testing, we identified the optimal formulation process for generating SH microspheres characterized by favorable morphology and particle size. Additionally, a similar single-factor examination focused on the concentration of the pore-forming agent and the drying temperature, leading to the successful production of mesoporous microspheres with discernible pores. The porosity of the three distinct batches of mesoporous microspheres was consistently measured at 20.30% ± 1.51%. Moreover, all these microspheres displayed a negative surface potential when suspended in water, affirming their strong capacity to bind with positively charged protein drugs. These findings underscored the feasibility of drug loading through ion exchange in subsequent stages. Notably, the successful preparation of recombinant human interferon α-2b crosslinked mesoporous microspheres (rhIFN α-2b-SHCMM) was achieved, demonstrating both high entrapment efficiency and an enhanced drug loading capacity. [ABSTRACT FROM AUTHOR]

A new niobate Ba6Mg0.67Nb9.33O30 was synthesized in the BaO−MgO−Nb2O5 system by solid state reaction at 1350°C for 48 h. The structure and dielectric properties of Ba6Mg0.67Nb9.33O30 were determined by X-ray powder diffraction, scanning electron microscopy and dielectric measurements. The results show that Ba6Mg0.67Nb9.33O30 belongs to ferroelectric phase of filled tetragonal tungsten bronze structure at room temperature with unit cell parameters: a=1.26052(4) nm, c=0.40045(2) nm, space group P4bm, calculated density 5.707 g·cm−3. Ba6Mg0.67Nb9.33O30 belongs to relaxor ferroelectrics undergoing diffusive phase transition, and the transition temperature (Tc) is 30°C observed at 10 kHz. At room temperature, Ba6Mg0.67Nb9.33O30 ceramic has a high dielectric constant 850 at 1 MHz and a low dielectric loss of 0.0052. [ABSTRACT FROM AUTHOR]

This study aimed to develop a cation-exchange resin suitable for pharmaceutical excipients, with an appropriate particle size to create an in situ gel of timolol maleate, enhancing its safety and efficacy for ophthalmic use. A cation-exchange resin was prepared using dispersion seed swelling and sulfonation. This resin served as a carrier to form timolol maleate drug resin complexes by bath method. The star design effect surface method was employed to optimize the gel formulation, resulting in an in situ thermosensitive gel. Additionally, the intraocular hypertension model of New Zealand rabbits was investigated with the objective of reducing intraocular pressure. The study successfully produced cation-exchange resins with a particle size below 10 μm, suitable for ophthalmic application. The drug content of homemade gel drug content ranged from 97.69 % to 99.37 %, with a cumulative release of 93.07 % over 10 h. Compared to commercially available eye drops, the homemade gel demonstrated prolonged residence time and better sustained intraocular pressure reduction effect. [ABSTRACT FROM AUTHOR]

Orthorhombic In 0.5 Sc 1.5 Mo 3 O 12 thin films have been synthesized using the sol-gel spin coating. Influences of post-annealing temperatures on crystal structure, morphology, negative thermal expansion (NTE) and optical performances of the thin films were studied using XRD, SEM, XPS, high-temperature XRD and UV–Vis–NIR spectrophotometer. XRD and SEM results show that as-prepared thin film is in an amorphous state with a smooth and dense surface. Orthorhombic In 0.5 Sc 1.5 Mo 3 O 12 thin films were obtained after post-annealing in 550–750 °C. The higher the annealing temperature in 550–750 °C, the better the crystallinity of orthorhombic In 0.5 Sc 1.5 Mo 3 O 12 thin films. In addition, the grain size of the In 0.5 Sc 1.5 Mo 3 O 12 thin film also grows as the annealing temperature increases. The resulting orthorhombic In 0.5 Sc 1.5 Mo 3 O 12 thin films exhibit anisotropic NTE. Its volumetric coefficient of thermal expansion (CTE) is −3.44 × 10−6 °C−1, while the CTEs in a -, b - and c -axis directions are −4.70 × 10−6 °C−1, 5.37 × 10−6 °C−1, and -4.10 × 10−6 °C−1 in 25–700 °C, respectively. In addition, the transmittance of orthorhombic In 0.5 Sc 1.5 Mo 3 O 12 thin films post-annealed at 750 °C is around 87.75 %–95.03 %. [ABSTRACT FROM AUTHOR]

The potential application of recombinant human interleukin-2 (rhIL-2) in promoting immune cell proliferation and differentiation for the treatment of lung cancer is acknowledged. However, the inherent challenges associated with the short half-life and instability of rhIL-2 necessitate its encapsulation into microspheres for sustained release administration. In this study, the coaxial electrostatic spray technique was employed to fabricate rhIL-2-loaded core-shell microspheres. Quantum dots served as tracer materials, and the core-shell composite microspheres were fashioned with chitosan coating the rhIL-2 and quantum dots conjugates in the core layer and hyaluronic acid in the shell layer. A systematic exploration of factors such as carrier concentration, positive voltage, pinhole diameter, and spray flow rate was conducted using a single-factor method. The coaxial electrostatic spray process parameters for core-shell microsphere preparation were also meticulously optimized. The results indicated that the developed core-shell microspheres exhibited a favorable particle size ranging from 1.2 to 2.0 μm, accompanied by encapsulation efficiency and drug loading values of 78.39% ± 1.96% and 19.58 ± 2.76 μg/mg, respectively. In vitro release studies demonstrated a sustained release effect without any discernible burst release phenomenon. Biological activity assessments revealed that rhIL-2 within the core-shell microspheres mirrored the efficacy of the free protein drug. Additionally, in vivo imaging analysis attested to the active targeting properties of the microspheres. These findings robustly supported the successful development of sustained -release targeted rhIL-2-loaded microspheres, providing a theoretical foundation for protein-microsphere formulations. [ABSTRACT FROM AUTHOR]

17β-estradiol (E2) is a natural endocrine disruptor that is frequently detected in surface and groundwater sources, thereby threatening ecosystems and human health. The newly isolated E2-degrading strain Sphingomonas colocasiae C3-2 can degrade E2 through both the 4,5-seco pathway and the 9,10-seco pathway; the former is the primary pathway supporting the growth of this strain and the latter is a branching pathway. The novel gene cluster ean was found to be responsible for E2 degradation through the 4,5-seco pathway, where E2 is converted to estrone (E1) by EanA, which belongs to the short-chain dehydrogenases/reductases (SDR) superfamily. A three-component oxygenase system (including the P450 monooxygenase EanB1, the small iron-sulfur protein ferredoxin EanB2, and the ferredoxin reductase EanB3) was responsible for hydroxylating E1 to 4-hydroxyestrone (4-OH-E1). The enzymatic assay showed that the proportion of the three components is critical for its function. The dioxygenase EanC catalyzes ring A cleavage of 4-OH-E1, and the oxidoreductase EanD is responsible for the decarboxylation of the ring A-cleavage product of 4-OH-E1. EanR, a TetR family transcriptional regulator, acts as a transcriptional repressor of the ean cluster. The ean cluster was also found in other reported E2-degrading sphingomonads. In addition, the novel two-component monooxygenase EanE1E2 can open ring B of 4-OH-E1 via the 9,10-seco pathway, but its encoding genes are not located within the ean cluster. These results refine research on genes involved in E2 degradation and enrich the understanding of the cleavages of ring A and ring B of E2. [ABSTRACT FROM AUTHOR]

The article presents a study for knowing the result of using shallow needling method for the treatment of Peripheral facial paralysis in Chinese medicine,.

The aim of the present study was to analyze the characteristics of angiogenic factors in patients with hypopharyngeal cancer, and to study the effects of these factors on induction chemotherapy, patient prognosis and survival. Data from 60 eligible patients with hypopharyngeal cancer that were treated between January 2012 and December 2016 were collected retrospectively. The differential expression of angiogenic factors in tumor and peritumoral tissues was analyzed retrospectively to assess the association between five differentially expressed genes, including interleukin (IL)-1β, transforming growth factor (TGF)-β, matrix metalloproteinase-9 (MMP-9), angiopoietin-2 and interferon-inducible T-cell α chemoattractant, and clinicopathological characteristics in different types of chemotherapy-associated blood vessels within samples of poorly differentiated hypopharyngeal cancer. The χ² test or t-test was used to compare the frequency data, the Kaplan-Meier method was used for survival analysis and the log-rank test was used to compare the Kaplan-Meier curves. P<0.05 was considered to indicate a statistically significant difference. The results of the present study demonstrated that there was a significant difference in the expression levels of vascular-associated factors between hypopharyngeal carcinoma and peritumoral tissues. Additionally, the results revealed a significant difference in the overall survival and prognosis of patients with a decreased vascular classification compared with patients with an unchanged vascular classification, which was assessed using narrowband imaging (NBI) following induction chemotherapy (P<0.05). The results of single factor analysis indicated that IL-1β, TGF-β and MMP-9 were associated with decreased blood vessel classification (P<0.05). In conclusion, IL-1β, TGF-β and MMP-9 may be used as predictors of the effect of induction chemotherapy on poorly differentiated hypopharyngeal cancer. Therefore, when patients with advanced hypopharyngeal cancer undergo chemotherapy, NBI vascular examination and screening for associated vascular factors should be performed before and after chemotherapy. Alterations in vascular classification, assessed using NBI, and abnormal expression of vascular factors may also be used as reference factors for prognosis. [ABSTRACT FROM AUTHOR]

Vertically aligned, highly ordered, large area arrays of nanostructures are important building blocks for multifunctional devices. Here, ZnO nanorod arrays are selectively synthesized on Si substrates by a solution method within patterns created by nanoimprint lithography. The growth modes of two dimensional nucleation-driven wedding cakes and screw dislocation-driven spirals are inferred to determine the top end morphologies of the nanorods. Sub-bandgap photoluminescence of the nanorods is greatly enhanced by the manipulation of the hydrogen donors via a post-growth thermal treatment. Lasing behavior is facilitated in the nanorods with faceted top ends formed from wedding cakes growth mode. This work demonstrates the control of morphologies of oxide nanostructures in a large scale and the optimization of the optical performance. [ABSTRACT FROM AUTHOR]

In the conventional fabrication process of the widely-adopted Ni/Ag/Ti/Au reflector for InGaN/GaN-based flip-chip light-emitting diodes (LEDs), the contact and the mirror are entangled together with contrary processing conditions which set constraints to the device performance severely. Here we first report the concept and its effectiveness of decoupling the contact formation and the mirror construction. The ohmic contact is first formed by depositing and annealing an extremely thin layer of Ni/Ag on top of p-GaN. The mirror construction is then carried out by depositing thick layer of Ag/Ti/Au without any annealing. Compared with the conventional fabrication method of the reflector, by which the whole stack of Ni/Ag/Ti/Au is deposited and annealed together, the optical output power is improved by more than 70% at 350 mA without compromising the electrical performance. The mechanism of decoupling the contact and the mirror is analyzed with the assistance of contactless sheet resistance measurement and secondary ion mass spectrometry (SIMS) depth profile analysis. [ABSTRACT FROM AUTHOR]

We have designed a decagonal photonic quasi-crystal (PQC) flat lens, which turns an incident terahertz (THz) plane wave into a hollow beam easily and flexibly. The features of the THz hollow beam can be controlled by varying the parameters of a point defect in the center of the lens, i.e., the PQC flat lens can be used as a flexible tool for THz optical captivity or optical tweezer. The results showing that an airy disk, whose mean beam width is similar to the incident wavelength and power-in-the-bucket (PIB) is more than 96%, can be generated in the far field. [ABSTRACT FROM AUTHOR]

Celecoxib is a specific cyclooxygenase-2 inhibitor with poor solubility and low bioavailability. A solid selfmicroemulsifying drug delivery system of celecoxib was therefore developed to improve in vitro drug solubility and in vivo absorption. Solubility testing, compatibility testing and pseudo-ternary phase diagrams were employed in the design. Morphological observation, droplet size and in vitro release were used to characterize the formulation. The optimized celecoxib-liquid self-microemulsifying drug delivery system was determined as 10 % of celecoxib, 25 % of medium chain triglycerides, 56.25 % of emulsifier and 18.75 % of Transcutol HP. 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide assay was used to investigate the cytoxicity of active pharmaceutical ingredients, blank self-microemulsion and celecoxib liquid self-microemulsifying drug delivery system on Caco-2 cells. Celecoxib solid self-microemulsifying drug delivery system was prepared with Neusilin-US2 as a solid adsorbent and characterized using scanning electron microscopy, X-ray, Fourier-transform infrared spectroscopy, differential scanning calorimetry and in vitro release. Celecoxib liquid self-microemulsifying drug delivery system had a clear and transparent light-yellow appearance with average particle size of about 22.68 nm, zeta potential of -31.92 mv, and polydisperse coefficient of 0.141. 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide results showed that the formulations virtually had no cytotoxic effect on the cells. The results also showed that celecoxib existed in an amorphous state in celecoxib-solid self-microemulsifying drug delivery system, and the celecoxib-liquid self-microemulsifying drug delivery system and celecoxib-solid-self-microemulsifying drug delivery system had a dissolution degree of more than 90 % in different media with good stability. The pharmacokinetic studies showed that the area under curve of the liquid self-microemulsifying drug delivery system and self-microemulsifying drug delivery system increased by 6.59 and 6.37 folds, respectively, compared with celecoxib suspension. The findings showed that the developed solid self-microemulsion formulations improved the bioavailability of the drug with no cytotoxicity, hence the formulation can serve as a promising carrier for the oral delivery of celecoxib. [ABSTRACT FROM AUTHOR]

We report on the effects of substrate, starting material, and temperature on the growth of MoS2 atomic layers by thermal vapor sulfurization in a tube-furnace system. With Mo as the starting material, atomic layers of MoS2 flakes are obtained on sapphire substrates while a bell-shaped MoS2 layer, sandwiched by amorphous SiO2, is obtained on native-SiO2/Si substrates under the same sulfurization conditions. An anomalous thickness-dependent Raman shift (A1g) of the MoS2 atomic layers is observed in Mo-sulfurizations on sapphire substrates, which can be attributed to the competition between the effects of thickness and the surface/interface. Both effects vary with the sulfurizing temperatures for a certain initial Mo thickness. The anomalous frequency trend of A1g is missing when using MoO3 instead of Mo as the starting material. In this case, the lateral growth of MoS2 on sapphire is also largely improved. Furthermore, the area density of the resultant MoS2 atomic layers is significantly increased by increasing the deposition temperature of the starting MoO3 to 700 °C; the adjacent ultrathin MoS2 grains coalesce in one or other direction, forming connected chains in wafer scale. The thickness of the so-obtained MoS2 is generally controlled by the thickness of the starting material; however, the structural and morphological properties of MoS2 grains, towards large area and continuous atomic layers, are strongly dependent on the temperature of the initial material deposition, and on the temperature of sulfurization, because of the competition between surface mobility and atom evaporation. [ABSTRACT FROM AUTHOR]

In our previous study, the phenazine-1-carboxylic acid (PCA) 1,2-dioxygenase gene cluster (pcaA1A2A3A4 cluster) in Sphingomonas histidinilytica DS-9 was identified to be responsible for the conversion of PCA to 1,2-dihydroxyphenazine (Ren Y, Zhang M, Gao S, Zhu Q, et al. 2022. Appl Environ Microbiol 88:e00543-22). However, the regulatory mechanism of the pcaA1A2A3A4 cluster has not been elucidated yet. In this study, the pcaA1A2A3A4 cluster was found to be transcribed as two divergent operons: pcaA3-ORF5205 (named A3-5205 operon) and pcaA1A2-ORF5208-pcaA4-ORF5210 (named A1-5210 operon). The promoter regions of the two operons were overlapped. PcaR acts as a transcriptional repressor of the pcaA1A2A3A4 cluster, and it belongs to GntR/FadR family transcriptional regulator. Gene disruption of pcaR can shorten the lag phase of PCA degradation. The results of electrophoretic mobility shift assay and DNase I footprinting showed that PcaR binds to a 25-bp motif in the ORF5205-pcaA1 intergenic promoter region to regulate the expression of two operons. The 25-bp motif covers the 210 region of the promoter of A3-5205 operon and the 235 region and 210 region of the promoter of A1-5210 operon. The TNGT/ANCNA box within the motif was essential for PcaR binding to the two promoters. PCA acted as an effector of PcaR, preventing it from binding to the promoter region and repressing the transcription of the pcaA1A2A3A4 cluster. In addition, PcaR represses its own transcription, and this repression can be relieved by PCA. This study reveals the regulatory mechanism of PCA degradation in strain DS-9, and the identification of PcaR increases the variety of regulatory model of the GntR/FadR-type regulator. IMPORTANCE Sphingomonas histidinilytica DS-9 is a phenazine-1-carboxylic acid (PCA)- degrading strain. The 1,2-dioxygenase gene cluster (pcaA1A2A3A4 cluster, encoding dioxygenase PcaA1A2, reductase PcaA3, and ferredoxin PcaA4) is responsible for the initial degradation step of PCA and widely distributed in Sphingomonads, but its regulatory mechanism has not been investigated yet. In this study, a GntR/FadR-type transcriptional regulator PcaR repressing the transcription of pcaA1A2A3A4 cluster and pcaR gene was identified and characterized. The binding site of PcaR in ORF5205-pcaA1 intergenic promoter region contains a TNGT/ANCNA box, which is important for the binding. These findings enhance our understanding of the molecular mechanism of PCA degradation. [ABSTRACT FROM AUTHOR]

Purpose: To prepare ranitidine hydrochloride (RH) sustained-release suspension aimed at improving its safety, effectiveness and convenience of administration. Methods: The RH resinate suspension was prepared using bath method, with a cation- exchange resin as carrier. To obtain an ideal sustained release effect, RH resinates were coated with Eudragit®RS100 using the surface coating method, followed by optimization through a single-factor experiment and response surface analysis. The optimized RH suspension was characterized using accelerated stability test. Moreover, it was pharmacokinetically evaluated in vivo. Results: The optimized RH resin microcapsules showed relative mean deviation between the predicted and measured release values that was < 10 %, (p < 0.05) and demonstrated good reproducibility. Accelerated stability test results showed that the optimized RH suspension exhibited good stability over a period of 6 months (F > 0.9; drug content: 97 – 100 %, drug release: f2 > 50; drug leakage < 0.5 %), with good redispersibility. Results from pharmacokinetics showed that values of Tmax for RH sustainedrelease suspension and RH common tablet were 4.00 and 2.5 h, respectively (p < 0.05), while the corresponding Cmax values were 2545.78 and 3245.97 ng/mL, respectively (p < 0.05). Results of analysis of AUC0-24 showed that they were equivalent in terms of AUC0-24 (p < 0.05) and bioavailability of 101.05%. Conclusion: The optimized ranitidine hydrochloride (RH) sustained-release suspension has been successfully prepared using ion-exchange resin as a carrier and Eudragit® RS100 as a coating material. [ABSTRACT FROM AUTHOR]

High entropy alloys (HEAs), consisting of five or more elements with nearly equal atomic composition with one another (5–35%), are new-generation alloys that have attracted signifi)cant interest since their advent in 2004 because of their unique structural and mechanical properties and thermodynamic and chemical stability. Some characteristics, including high mechanical strength at elevated temperatures, high ductility and fracture toughness at cryo)genic temperatures and high corrosion, erosion and wear resistance, have been demonstrated for HEAs that outperform traditional alloys and superalloys. Laser-cladding (LC) is an additive manufacturing technique that has good feasibility in designing and processing HEAs for advanced structural components and protective coatings. This overview provides a glimpse of recent advances in LC of HEAs in terms of design fundamentals, metallurgical phase and microstructure, specific properties for advanced coating applications and the effect of ceramic particles reinforcement in LC deposition of HEA coatings. [ABSTRACT FROM AUTHOR]

The parameters of elliptical tank can greatly affect the roll stability of the elliptical tank with different filled levels, the exact equations for the mass centre of the tank were developed. The solutions of the transient mass centre of sloshing liquid in a tank with modified elliptical cross sections were obtained by a new vehicle rollover model. To achieve Euler transform 6-degree of freedom (DOF) motion equation of tank, Liquid Sloshing model of partially-filled tank was built by Nonlinear External Excitation. In addition, MATLAB ODE was used to investigate the numerical simulation. According to the different filled level of the tank by simulating, force and moment about X, Y and Z-axis of the coordinates of the mass centre were obtained. It is shown that the nonlinear mathematical models of liquid sloshing and vehicle motion equation can accurately describe the tank truck dynamic response in turing. The finding of this study may provide a theoretical basis to improve the roll stability of the tank. [ABSTRACT FROM AUTHOR]

To study the factors affecting the driving stability of tank trucks under dangerous working conditions, a full vehicle dynamics model and an equivalent test bench for liquid sloshing were designed. On the test bench, two dangerous working conditions were simulated to study liquid sloshing, i.e. braking and turning. The results show that the liquid sloshing force have a major impact on driving stability and the forces depended on the tank geometry, the fill level and the natural sloshing frequency of the liquid. The results of this study still provide a theoretical and experimental basis for studying further the factors that affect the driving stability of tank trucks. [ABSTRACT FROM AUTHOR]

Pt-based alloy catalysts may promise considerable mass activity (MA) for oxygen reduction but are generally unsustainable over long-term cycles, particularly in practical proton exchange membrane fuel cells (PEMFCs). Herein, we report a series of Pt-based intermetallic compounds (Pt3Co, PtCo, and Pt3Ti) enclosed by ultrathin Pt skin with an average particle size down to about 2.3 nm, which deliver outstanding cyclic MA and durability for oxygen reduction. By breaking size limitation during ordered atomic transformation in Pt alloy systems, the MA and durability of subsize Pt-based intermetallic compounds can be simultaneously optimized. The subsize scale was also found to enhance the stability of the membrane electrode through preventing the poisoning of catalysts by ionomers in humid fuel-cell conditions. We anticipate that subsize Pt-based intermetallic compounds set a good example for the rational design of high-performance oxygen reduction electrocatalysts for PEMFCs. Furthermore, the prevention of ionomer poisoning was identified as the critical parameter for assembling robust commercial membrane electrodes in PEMFCs. [ABSTRACT FROM AUTHOR]

Background. Neuroblastoma (NB) is the most common extracranial solid tumor in infants and children. Its variable location and complex pathogenesismake NB hard for early diagnosis and risk classification. Methodology. We analyzed the methylation data of 236 samples from patients with NB in Therapeutically Applicable Research to Generate Effective Treatments (TARGET) database. Kaplan--Meier survival analysis was used for comparing overall survival of NB patients in different groups. Epigenome-wide association study (EWAS) was conducted to screen CpGs significantly associated with NB patients' Children's Oncology Group (COG). Logistic regression method was used for constructing a model to predict NB patients' COG. Results. NB patients in low COG showed significantly superior prognosis than those in high COG. A total of seven CpG sites were found closely related to COG. Logistic regression model based on those CpGs showed superior performance in separating NB patients in different COGs. Conclusions. The present study highlights the important role of DNA methylation in NB development, which might provide evidence for treatment decisions for children NB. [ABSTRACT FROM AUTHOR]