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The aim of this study was to compare the effects of jumping interval training (JIT) and running high-intensity interval training (HIIT) on the aerobic, anaerobic and jumping performances of youth female aerobic gymnasts. A randomized controlled study was conducted over an 8-week period, involving 73 youth female athletes (16.2 ± 1.3 years old) of aerobic gymnastics. The study comprised two experimental groups (JIT and HIIT) and a control group. Participants in the experimental groups engaged in two additional training sessions per week alongside their regular training regimen, while the control group followed their usual training routine. Before and after the intervention period, gymnasts were assessed for their performance in the countermovement jump test (CMJ), the specific aerobic gymnastics anaerobic test (SAGAT) and the 20-m multistage fitness test. Significant interactions time x group were found in SAGAT ( p < 0.001; ηp² = 0.495), CMJ (p < 0.001; ηp²= 0.338) and 20-m multistage fitness test (p < 0.001; ηp² = 0.500). The time x group analysis post-intervention revealed significantly lower scores in SAGAT for the control group compared to the JIT (p = 0.003) and HIIT (p = 0.034). Additionally, significantly higher scores were observed for the JIT group in the CMJ test compared to the HIIT (p = 0.020) and control (p = 0.028) groups following the intervention. Finally, the 20 m multistage fitness test post-intervention revealed significantly lower scores for the control group compared to JIT (p < 0.001) and HIIT (p < 0.001). Both JIT and HIIT are recommended training strategies to adopt in aerobic gymnastics for significantly improving the aerobic and anaerobic performances of athletes. However, JIT may be particularly relevant to use as it offers additional benefits in improving vertical jumping performances. [ABSTRACT FROM AUTHOR]

Organized flaking techniques to obtain predetermined stone tools have been traced back to the early Acheulean (also known as mode 2) in Africa and are seen as indicative of the emergence of advanced technical abilities and in-depth planning skills among early humans. Here, we report one of the earliest known examples of prepared core technology in the archaeological record, at the Cenjiawan (CJW) site in the Nihewan basin of China, dated 1.1 Mya. The operational schemes reconstructed from the CJW refit sets, together with shaping patterns observed in the retouched tools, suggest that Nihewan basin toolmakers had the technical abilities of mode 2 hominins, and developed different survival strategies to adapt to local raw materials and environments. This finding predates the previously earliest known prepared core technology from Eurasia by 0.3 My, and the earliest known mode 2 sites in East Asia by a similar amount of time, thus suggesting that hominins with advanced technologies may have migrated into high latitude East Asia as early as 1.1 Mya. [ABSTRACT FROM AUTHOR]

Based on wire arc additive manufacturing (WAAM) technology, AZ31 magnesium alloy in bulk was successfully fabricated, and its microstructure as well as mechanical properties in different planes were observed and analyzed. The AZ31 magnesium alloy has a similar microstructure in the building direction (Z) and travel direction (X), both of which are equiaxed grains. There are heat-affected zones (HAZs) with coarse grains below the fusion line. The second phase is primarily composed of the Mg17Al12 phase, which is evenly distributed in different directions. In addition, the residual stress varies in different directions. There is no significant difference in the hardness of the AZ31 alloy along the Z and X directions, with the average hardness being 68.4 HV and 67.9 HV, respectively. Even though the specimens’ ultimate tensile strength along the travel direction is higher in comparison to that along the building direction, their differences in elongation and yield strength are smaller, indicating that the anisotropy of the mechanical properties of the material is small. [ABSTRACT FROM AUTHOR]

A detailed and systematic investigation on the effect post heat treatment has on the microstructure evolution and the resultant mechanical properties of the wire arc additive manufacturing processed Mg-5.9Gd-2.8Y-0.7Zr alloy is conducted in this work. The microstructure of the as-built sample is composed mainly of fine equiaxed α-Mg grain and Mg24(Gd, Y)5 phase. The solution heat treatment (400°C × 1 h) has relatively little effect on grain size, but it can effectively reduce the content of the Mg24(Gd, Y)5 phase, which leads to a significantly improved elongation with slightly decreased strength. Further ageing heat treatment at 200°C induces prismatic β' precipitates formation and does not influence other phases and grain size. The samples directly following the peak ageing heat treatment process demonstrate the best tensile properties with yield strength of 227 ± 9 MPa, ultimate tensile strength of 350 ± 4 MPa and elongation of 5.5 ± 0.6%. [ABSTRACT FROM AUTHOR]

Eight steel reinforced high-strength concrete composite walls were manufactured and quasi-statically tested. The testing objective was to investigate the seismic behavior of composite walls, including the failure mode, hysteresis curve, deformation, energy dissipation, and stiffness degradation. The results showed that all specimens failed during the flexural mode. The lateral load-resisting capability and deformation capability significantly increased with increasing steel ratio and stirrup characteristic value. In addition, formulations were proposed to evaluate the lateral load-resisting capability of steel reinforced concrete (SRC) composite walls, and the evaluated results exhibited good agreement with the test results. [ABSTRACT FROM AUTHOR]

sdBV rs is a particular type of hot subdwarfs which have both p-mode and g-mode pulsations. It is unclear of the formation channel of such hot subdwarfs stars. The merger of a He core white dwarf (HeWD) with a main sequence (MS) star can produce a hot subdwarf. We propose that sdBV rs may form from this channel. We compute the models of the remnants of some of these mergers, and perform detailed stability analysis. By comparing to observations, the evolutionary tracks of the remnants of mergers can match with the sdBV rs in effective temperature-surface gravity diagram. These models also have both p-mode and g-mode pulsations been excited. Our result indicates that the merger of a HeWD with a MS star might be one of the formation channels of sdBV rs stars. [ABSTRACT FROM AUTHOR]

Metakaolin (MK), which has a fine particle size and higher activity in high alkaline environments, has been widely used in the fields of soil treatment engineering to stabilize soils. MK is used to replace part of ordinary Portland cement (OPC) with 0 : 15, 2 :13, 4 : 11 and 6 : 9 mass ratios of MK to OPC in this study. The mechanical property (e.g. stress-strain relationship, strength, and deformation performance) and microstructure characteristics of MK-based geopolymer cemented silty clay are investigated using unconfined compressive strength (UCS), nuclear magnetic resonance (NMR), and scanning electronic microscopy (SEM) tests. In addition, strength increase coefficient (ζs) and elasticity modulus increase coefficient (ζe) are defined to evaluate the effects of curing time on the mechanical property of MK-based geopolymer cemented silty clay. Moreover, the relationships among porosity, UCS, and E50 of MK-cemented silty clay are studied. By incorporating 2% MK, the UCS and E50 of MK-cemented silty clay at 28 d are 1.32 and 1.30 times compared with MK0 group, respectively. The increase rate of UCS and E50 from 1 d to 7 d is faster compared with that from 7 d to 28 d. Furthermore, the microstructure of the sample modified by 2% MK is most homogeneous and dense. Finally, the optimistic mass ratio between MK and cement is 2 : 13 for silty clay in this test condition. [ABSTRACT FROM AUTHOR]

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, left1/2R 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. [ABSTRACT FROM AUTHOR]

A total of 192 native rice germplasm lines from the cold region of Northeast China were analyzed for rice sheath blight resistance at the late tillering stage using the toothpick embedding method. Disease rating, absolute disease lesion height, relative lesion length and lesion length served as indicators of sheath blight resistance. Germplasm resources were then subjected to population structure analysis and linkage disequilibrium analysis in order to identify disease resistance markers for use in marker-assisted breeding for sheath blight resistance. The germplasm resources were segregated into three main groups. Notably, a total of nine markers were significantly associated with rice sheath blight resistance; eight of these markers(OSR23, RM270, RM339, RM470, RM536, RM569,RM1022, RM1163) were associated with disease rating. The additional marker RM283 was associated with both relative lesion length and lesion length and made a high contribution to the rate of phenotypic variation. Ultimately, the sheath blight resistance markers described in this study could be useful for rice marker-assisted selection of sheath blight resistant cultivars breeding. [ABSTRACT FROM AUTHOR]

To find novel butyrylcholinesterase inhibitors, three novel 2-phenylthiazole derivatives were synthesised. The synthesised compounds were characterised by NMR and single-crystal X-ray diffraction analysis. Hirshfeld surface analysis and two-dimensional fingerprint plots of the compounds were used as a theoretical approach to assess the driving force for crystal structure formation via the intermolecular interactions in the crystal lattices of the synthesised compounds. Among the three compounds, N-(1,5-dimethyl-3-oxo-2-phenyl-2,3- dihydro- 1H-pyrazol-4-yl)-2-(4-methoxyphenyl)thiazole-4-carboxamide showed the best butyrylcholinesterase-inhibition activity with an IC50 value of 75.12 µM. A docking study demonstrated that this compound interacts with the peripheral anionic site of butyrylcholinesterase. [ABSTRACT FROM AUTHOR]

We compared responses from postmenopausal women living a sedentary lifestyle (n = 15; Mean age= 59; SD = 4.2) to a single bout of water- or land-based exercise with respect to ratings of perceived exertion (RPE), lactate concentration, and muscle oxygen saturation. Each participant was randomly assigned to a single water- or land-based 50-minute bout of combined aerobic and resistance exercise. Blood samples were collected to detect pre- and post-exercise lactate concentration. Total hemoglobin, deoxidized hemoglobin, and the percentage change in the total oxygen saturation index (TSI%) of the rectus femoris were detected by means of near-infrared spectroscopy. We found similar RPE at various stages of land- and water-based exercise, and a similar change in lactate concentration in these environments (in water: 4.35 ± 1.49mol/L; on land: 3.62 ± 1.18mol/L). However, the reduction in HHb response was less pronounced after water-based exercise, and TSI% increased on land but decreased in water, with the magnitude of this change much higher on land. For similar RPE and lactate concentration, the oxygen saturation in the exercising muscles decreased in water, suggesting higher oxygen consumption in water than on land. [ABSTRACT FROM AUTHOR]

Epstein-Barr virus (EBV) infection is associated with B cell lymphomas in humans. The ability of EBV to convert human B cells into long-lived lymphoblastoid cell lines (LCLs) in vitro requires the collaborative effects of EBNA2 (which hijacks Notch signaling), latent membrane protein 1 (LMP1) (which mimics CD40 signaling), and EBV-encoded nuclear antigen 3A (EBNA3A) and EBNA3C (which inhibit oncogene-induced senescence and apoptosis). However, we recently showed that an LMP1-deleted EBV mutant induces B cell lymphomas in a newly developed cord blood-humanized mouse model that allows EBV-infected B cells to interact with CD4 T cells (the major source of CD40 ligand). Here we examined whether the EBV LMP2A protein, which mimics constitutively active B cell receptor signaling, is required for EBV-induced lymphomas in this model. We find that the deletion of LMP2A delays the onset of EBV-induced lymphomas but does not affect the tumor phenotype or the number of tumors. The simultaneous deletion of both LMP1 and LMP2A results in fewer tumors and a further delay in tumor onset. Nevertheless, the LMP1/LMP2A double mutant induces lymphomas in approximately half of the infected animals. These results indicate that neither LMP1 nor LMP2A is absolutely essential for the ability of EBV to induce B cell lymphomas in the cord blood-humanized mouse model, although the simultaneous loss of both LMP1 and LMP2A decreases the proportion of animals developing tumors and increases the time to tumor onset. Thus, the expression of either LMP1 or LMP2A may be sufficient to promote early-onset EBV-induced tumors in this model. [ABSTRACT FROM AUTHOR]

Changbai Mountain Ginseng (CMG, Panax ginseng C.A. Mey) is a traditional medicine commonly found in Northeast China and grows at elevations of 2000 m or higher in the Changbai Mountain Range. CMG, considered to be a "buried treasure medicine", is priced higher than other types of ginseng. However, few studies have demonstrated the effects of CMG supplementation on exercise performance, physical fatigue, and the biochemical profile. The major compound of CMG extract was characterized by electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS). Male ICR mice were divided into 3 groups, the vehicle, CMG-1X and CMG-5X groups (n = 8 per group), and respectively administered 0, 5, or 25 mg/kg/day of CMG extract orally for four weeks. HPLC-ESI-MS/MS results showed that the major compound in CMG extract is ginsenoside Ro. CMG extract significantly increased muscle weight and relative muscle weight (%). CMG extract supplementation dose-dependently increased grip strength (p < 0.0001) and endurance swimming time, decreased levels of serum lactate (p < 0.0001), ammonia (p < 0.0001), creatine kinase (CK, p = 0.0002), and blood urea nitrogen (p < 0.0001), and economized glucose levels (p < 0.0001) after acute exercise challenge. The glycogen in the gastrocnemius muscle was significantly increased with CMG extract treatment. Biochemical profile results showed that creatinine and triacylglycerol significantly decreased and total protein and glucose increased with CMG treatment. This is the first report that CMG extract supplementation increases muscle mass, improves exercise performance and energy utilization, and decreases fatigue-associated parameters in vivo. The major component of CMG extract is ginsenoside Ro, which could be a potential bioactive compound for use as an ergogenic aid ingredient by the food industry. [ABSTRACT FROM AUTHOR]

The gentamicin-loaded nano-sized liposomes are shown to penetrate into alginate-based Ralstonia insidiosa bacterial biofilms by acoustic streaming generated by moderate pulsed ultrasound (frequency=2.25 MHz, 10% duty cycle and spatially and temporally averaged intensity, ISATA ≈ 4.4 W/cm2). The liposomes are then burst by the scanned relatively high intensity ultrasound (frequency=1.1 MHz, 10% duty cycle, the spatially and temporally averaged intensity ISATA ≈ 90 W/cm2) in situ, and the gentamicin solution is released from the liposomes resulting in 72% of Ralstonia insidiosa killing. [ABSTRACT FROM AUTHOR]

Relative permeability as an important petrophysical parameter is often measured directly in the laboratory or obtained indirectly from the capillary pressure data. However, the literature on relationship between relative permeability and resistivity is lacking. To this end, a new model of inferring two-phase relative permeability from resistivity index data wav derived on the basis of Poiseuille's law and Darcy's law. The wetting phase tortuosity ratio was included in the proposed model. The relative permeabilities computed from the capillary pressure data, as well as the experimental data measured in gas-water and oil-water flow condition, were compared with the proposed model. Both results demonstrated that the two-phase permeability obtained by proposed model were generally in good agreement with the data computed from capillary pressure and measured in the laboratory. The comparison also showed that our model was much better than Li model at matching the relative permeability data. [ABSTRACT FROM AUTHOR]

Epstein-Barr virus (EBV) infection transforms B cells in vitro and is associated with human B cell lymphomas. The major EBV oncoprotein, latent membrane protein 1 (LMP1), mimics constitutively active CD40 and is essential for outgrowth of EBV-transformed B cells in vitro; however, EBV-positive diffuse large B cell lymphomas and Burkitt lymphomas often express little or no LMP1. Thus, EBV may contribute to the development and maintenance of human lymphomas even in the absence of LMP1. Here, we found that i.p. injection of human cord blood mononuclear cells infected with a LMP1-deficient EBV into immunodeficient mice induces B cell lymphomas. In this model, lymphoma development required the presence of CD4+ T cells in cord blood and was inhibited by CD40-blocking Abs. In contrast, LMP1-deficient EBV established persistent latency but did not induce lymphomas when directly injected into mice engrafted with human fetal CD34+ cells and human thymus. WT EBV induced lymphomas in both mouse models and did not require coinjected T cells in the cord blood model. Together, these results demonstrate that LMP1 is not essential for EBV-induced lymphomas in vivo and suggest that T cells supply signals that substitute for LMP1 in EBV-positive B cell lymphomagenesis. [ABSTRACT FROM AUTHOR]

Objective: To explore the relationship between methylation of interferon gamma (IFN-λ) gene and tumorigenesis in cervical cancer tissues, the biopsy specimens of cervical cancer and cervical intraepithelial neoplasia (CIN) (I-III) patients as well as normal controls were collected and analyzed. Methods: The methylation of the IFN-λ gene was verified by using methylation-specific PCR and DNA sequencing analysis, and the expression levels of IFN-λ mRNA were detected using quantitative real-time reverse transcriptase-polymerase chain reaction (qRT-PCR). Results: The methylation rates of the IFN-λ gene were significantly higher in cervical cancer tissues (15/43, 34.9%) than those in CIN (3/23, 13.0% of CIN I; 6/39, 15.4% of CIN II/III) and normal cervical tissues (2/43, 4.7%) (P<0.01). Furthermore, them RNA expression of IFN-λ in cervical tumors with methylation (0.71 ± 0.13, n=8) was lower than that in those without methylation (1.58 ± 0.32, n=27) (P<0.05). Likewise, the IFN-λ expression levels in CIN II/III tissues with methylation (0.87 ± 0.16, n=5) were significantly (P<0.01) lower compared to those without methylation (2.12 ± 0.27, n=32). Conclusion: The hypermethylation of IFN-λ gene may be related with tumorigenesis of cervical cancer. [ABSTRACT FROM AUTHOR]

Chimaphilin, 2,7-dimethyl-1,4-naphthoquinone, is extracted from pyrola [Passiflora incarnata Fisch.]. In this study, the anticancer activity and underlying mechanisms of chimaphilin toward human breast cancer MCF-7 cells are firstly investigated. Chimaphilin could inhibit the viability of MCF-7 cells in a concentration-dependent manner, and the IC50 value was 43.30 µM for 24 h. Chimaphilin markedly induced apoptosis through the investigation of characteristic apoptotic morphological changes, nuclear DNA fragmentation, annexin V-FITC/propidium iodide (PI) double staining. Flow cytometry assay revealed that chimaphilin triggered a significant generation of ROS and disruption of mitochondrial membrane potential. Additionally, western blotting assay showed that chimaphilin suppressed Bcl-2 level and enhanced Bad level, then activated caspase-9 and caspase-3, and further activated the poly ADP-ribose polymerase (PARP), finally induced cell apoptosis involving the mitochondrial pathway. Furthermore, free radical scavengers N-acetyl-L-cysteine (NAC) pretreatment test testified that chimaphilin could increase the generation of ROS, then induce cell apoptosis. In general, the present results demonstrated that chimaphilin induced apoptosis in human breast cancer MCF-7 cells via a ROS-mediated mitochondrial pathway. [ABSTRACT FROM AUTHOR]

A polymeric prodrug, PEGylated indomethacin (MPEG-indo), was prepared and then used to interact with α-cyclodextrin (α-CD) in their aqueous mixed system. This process could lead to the formation of supramolecular hydrogel under mild conditions and simultaneous encapsulation of MPEG-indo in the hydrogel matrix. For the formed supramolecular hydrogel, its gelation kinetics, mechanical strength, shear-thinning behavior and thixotropic response were investigated with respect to the effects of MPEG-indo and α-CD amounts by dynamic and steady rheological tests. Meanwhile, the possibility of using this hydrogel matrix as injectable drug delivery system was also explored. By in vitro release and cell viability tests, it was found that the encapsulated MPEG-indo could exhibit a controlled and sustained release behavior as well as maintain its biological activity. [ABSTRACT FROM AUTHOR]

The dynamic dilational properties of branched alkyl benzene sulfonates at the air-water and decane-water interfaces were investigated by drop shape analysis, and their lamella stability was measured. The influences of time, dilational frequency, and bulk concentration on surface dilational elasticity and dilational viscosity were expounded. The results show that the molecular interaction controls the nature of adsorption film during lower concentration range and the film behaves elastic in nature. During higher concentration range, the diffusion-exchange process controls the dynamic dilational properties and the surface film shows remarkable viscoelasticity. An increase in hydrophobic chain length enhances the molecular interaction, which results in the increase of dilational parameters and lamella stability. The data correlation suggests that the ability to form a stable lamella is linked to the intrinsic surface dilational elasticity. [ABSTRACT FROM AUTHOR]

Heparin, a powerful anticoagulant used for the prophylaxis of both surgical and medical thrombosis, was covalently incorporated into a supramolecular hydrogel network. For this attempt, heparin was first conjugated with amino-terminated poly(ethylene glycol) methyl ether by carbodiimide chemistry and then used to interact with α-cyclodextrin in aqueous solution. The rheological measurements and X-ray diffraction analyses were used to characterize the hydrogel formation. It was found that the gelation kinetics and hydrogel properties could be modulated by changing the amount of conjugated heparin or α-cyclodextrin. By circular dichroism analyses and in vitro release experiments, resultant hydrogel material was found to have a great potential as an injectable matrix for the encapsulation and sustained release of model protein drug (bovine serum albumin). By in vitro release, blood clotting, and hemolysis experiments, such a supramolecular hydrogel was also confirmed to have a controlled release profile for conjugated heparin and shows good anticoagulant and blood-compatible properties. [ABSTRACT FROM AUTHOR]

Previous study has shown that the degradation and aggregation of recombinant human consensus interferon-α mutant (cIFN) were serious when cIFN was secreted to bioreactor by Pichia pastoris. In this study, we showed that this phenomenon was concomitant well with the formation of the doublets of cIFN monomers that could be seen clearly on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The doublets were a mixture of two isomers formed by cIFN with different disulfide bonds and identified that the upper cIFN in doublets contains only one disulfide bond while the lower cIFN contains intact disulfide bonds by a novel method termed protein laddering map on SDS-PAGE. In addition, the instability of cIFN with different disulfide bond forms is also analyzed through a novel in vitro conversion assay based on incubation with different concentrations of β-mercaptoethanol. The results showed that only a wound such as cleavage of only one disulfide bond could be fatal to cIFN stability. If the disulfide bonds in cIFN monomers were broken, three kinds of aggregates would be formed easily: covalent aggregates, non-covalent aggregates, and unknown dimers. Likewise, the unfolded species also displayed reduced stability to proteolysis. These results indicate that the incomplete formation of disulfide bond in cIFN secreted to fermentation broth triggers severe degradation and aggregation of cIFN, which result in sharp decrease of bioactivity of cIFN in bioreactor. [ABSTRACT FROM AUTHOR]

Hydrophilic hydrogels based on poly(ethylene glycol)–poly(propylene glycol)–poly(ethylene glycol) block copolymers have potential applications in drug delivery, tissue engineering and other biomedical devices due to their excellent biocompatibility and environmental sensitivity. However, they also exhibit some shortcomings in terms of swelling and mechanical properties as well as affinity for water-insoluble or hydrophobic drug molecules. To address these limitations, new polymeric hydrogels with β-cyclodextrin moieties were prepared by UV photo-polymerization of maleic anhydride-substituted β-CD (MAH-CD) and the block copolymer macromer from Pluronic F68 and poly(ɛ-caprolactone). Their swelling and dynamic rheological properties were investigated with respect to the effects of feed compositions. It was found that the swelling ratio, storage modulus and loss modulus of the resulting hydrogel increased with the increase of MAH-CD amount. Incorporation of MAH-CD resulted in strong viscoelastic system with dominating elastic behavior. [ABSTRACT FROM AUTHOR]

For the fabrication of magnetically supramolecular hydrogels, the aqueous colloidal dispersion of magnetic iron oxide nanoparticles was first stabilized by an amphiphilic poly(ε-caprolactone)−poly(ethylene glycol) (PEG−PCL) block copolymer and then mixed with an aqueous solution of a cyclic oligosaccharide. Due to the host–guest interaction between the used block copolymer and the cyclic oligosaccharide in the aqueous mixed system, such a fabrication process could result in the formation of a novel hydrogel nanocomposite with superparamagnetic property, as confirmed by the analyses from rheology and X-ray diffraction as well as magnetization curve measurements. For the resultant magnetically supramolecular hydrogel, its formation kinetics and mechanical strength could be modulated by the amount of the used PEG−PCL block copolymer, the cyclic oligosaccharide, or the incorporated iron oxide nanoparticles. [ABSTRACT FROM AUTHOR]

Abstract  In this paper, a direct numerical simulation of a fully developed turbulent flow and heat transfer are studied in a square duct with an imposed temperature difference between the vertical walls and the perfectly insulated horizontal walls. The natural convection is considered on the cross section in the duct. The numerical scheme employs a time-splitting method to integrate the three dimensional incompressible Navier-Stokes equation. The unsteady flow field was simulated at a Reynolds number of 400 based on the Mean friction velocity and the hydraulic diameter (Re m = 6200), while the Prandtl number (Pr) is assumed 0.71. Four different Grashof numbers (Gr = 104, 105, 106 and 107) are considered. The results show that the secondary flow and turbulent characteristics are not affected obviously at lower Grashof number (Gr ≤  105) cases, while for the higher Grashof number cases, natural convection has an important effect, but the mean flow and mean temperature at the cross section are also affected strongly by Reynolds stresses. Compared with the laminar heat transfer at the same Grashof number, the intensity of the combined heat transfer is somewhat decreased. [ABSTRACT FROM AUTHOR]

Nucleation and growth of calcium oxalate (CaC2O4) crystals induced by films composed of phosphatidylcholine (PC), cholesterol (CS) and human serum albumin (HSA), and of PC, CS and dextran have been carried out. The products obtained were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy and ultraviolet-visible spectroscopy. The results indicate that hexagonal calcium oxalate monohydrate (COM) and club-shaped calcium oxalate trihydrate (COT) crystals are obtained on the PC/CH/HSA film, and the microstructure and properties of the PC/CH/HSA film depend on the weight ratio of PC to CS. With an increase in the PC-to-CS ratio, the number of COM crystals decreases gradually, and finally disappear, suggesting that PC inhibits the growth of COM crystals. On the PC/CS/dextran film, irregular COM and COT crystals are formed. The possible formation mechanisms of CaC2O4 on the two complex films are discussed. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

A multidomain topology optimization technique (MDTO) is developed, which extends the standard topology optimization method to the realm of more realistic engineering design problems. The new technique enables the effective design of a complex engineering structure by allowing the designer to control the material distribution among the subdomains during the optimal design process, to use multiple materials or composite materials in the various subdomains of the structure, and to follow a desired pattern or tendency for the material distribution. A new algorithm of Sequential Approximate Optimization (SAO) is proposed for the multidomain topology optimization, which is an enhancement and a generalization of previous SAO algorithms (including Optimality Criteria and Convex Linearization methods, etc.). An advanced substructuring method using quasi-static modes is also introduced to condense the nodal variables associated with the multidomain topology optimization problem, especially for the nondesign subdomains. The effectiveness of the new MDTO approach is demonstrated for various design problems, including one of "structure-fixture simultaneous design," one of "functionally graded material design," and one of "crush energy management." These case studies demonstrate the potential significance of the new capability developed for a wide range of engineering design problems. [ABSTRACT FROM AUTHOR]

Objective: To investigate the relationship between the DNA methylation state of NRG1 promoter and its expression changes, and to analyze the clinical significance of its regulatory mechanism of DNA methylation in cervical carcinoma. Methods: This was a retrospective study. One-hundred and twenty patients from the Department of Gynecology of Cangzhou People's Hospital from September 2017 to September 2019 were selected, including 40 cases of cervical SCC, 40 cases of high grade squamous intraepithelial lesions (HSIL) and 40 cases of control cervical tissues. RT-qPCR, immunohistochemistry and DNA methylation-specific PCR (MSP) were used to detect the mRNA and protein expression of NRG1 and DNA methylation status in different tissue types. Results: Immunohistochemical results showed that the positive protein expression rate of NRG1 gene in the SCC group was lower than that in both HSIL and Control groups. RT-qPCR results showed that the mRNA gene of NRG1 gradually decreased in expression with the increase of cervical tissue lesions, with a statistically significant difference. Similarly, it also found that the mRNA expression level of NRG1 in the SCC group was independent of patients' age (p>0.05), but significantly correlated with tumor pathological staging, surgical pathology staging and lymphatic metastasis (p<0.05). Furthermore, methylation-specific PCR results revealed a significantly higher DNA methylation rate of NRG1 gene in the SCC group than in both HSIL and Control groups, with a statistically significant difference. Moreover, the methylation degree of NRG1 gene in SCC tissues was negatively correlated with its mRNA expression (p<0.05). Conclusions: Abnormal DNA hypermethylation of NRG1 gene inhibits the expression of mRNA and protein in the progression of cervical tissue from normal to cancerous state, which is involved in the occurrence and development of cervical carcinoma. [ABSTRACT FROM AUTHOR]

Abstract: A one-pot route to 8-substituted xanthines has been developed from 5,6-diaminouracils and carboxaldehydes. The process, promoted by (bromodimethyl)sulfonium bromide, is mild and efficient and eliminates the need for external oxidants. Yields are good and the process is applicable to a range of substrates including a family of A2A adenosine receptor antagonists. Preparation of a new analog of the antagonist KW-6002 is presented, and in situ bromination of aryl substituted products demonstrated. [Copyright &y& Elsevier]

Subsonic-supersonic mixing flow is one of the important research fields in turbulence research. For example, in the combustion chamber of the rocket ramjet combination engine, the rocket jet flow and the air inflow is a typical shear mixing flow, which has the characteristics of high convection Mach number and large flow parameter gradient. It is of great significance to explore the development law and flow structure of subsonic-supersonic mixing layer to enhance the mixing and thus improve the performance of rocket ramjet engine. In this paper, in order to further study the evolution process and obtain the evolution mechanism and fine flow structure of subsonic-supersonic mixing layer, three groups of high-order format direct numerical simulations of typical working conditions are carried out. The convective Mach numbers are 0.69, 0.92 and 1.27, respectively. The direct numerical simulation results show that: (1) the large-scale structure in the subsonic-supersonic shear mixing flow formed the small-scale structure earlier, and the flow was dominated by the small-scale and broken eddy structure; (2) the development process of the subsonic-supersonic shear mixing flow was mainly divided into three stages: laminar flow zone, transition zone and development zone. The transition zone was a transition zone from two-dimensional to three-dimensional, which began to show three-dimensional flow characteristics. The vorticity shows a twisted-winding structure. The large-scale Coherent structure, the Λ eddy and hairpin eddy, can be observed, and the Λ eddy structure is gradually elongated with the increase of convective Mach number; (3) the shocklets structure mainly occurs in the stage when the mixing layer has not fully developed. The starting point of the shocklets structure is near the vortex core. With the increase of convective Mach number, the position of the shocklets generation moves to the front of the vortex core; (4) the dynamic mode decomposition results show that the eigenvalues of each mode are basically located in the unit circle, which indicates that the calculated modes are stable; in addition, it is found that there is a certain dominant frequency in the flow structure, which can provide a reference for the active mixing enhancement method. [ABSTRACT FROM AUTHOR]

A pinned photodiode complementary metal–oxide–semiconductor transistor (CMOS) active pixel sensor is exposed to 60Co to evaluate the performance for space applications. The sample is irradiated with a dose rate of 50 rad (SiO2)/s and a total dose of 100 krad (SiO2), and the photodiode is kept unbiased. The degradation of dark current, full well capacity, and quantum efficiency induced by the total ionizing dose damage effect are investigated. It is found that the dark current increases mainly from the shallow trench isolation (STI) surrounding the pinned photodiode. Further results suggests that the decreasing of full well capacity due to the increase in the density, is induced by the total ionizing dose (TID) effect, of the trap interface, which also leads to the degradation of quantum efficiency at shorter wavelengths. [ABSTRACT FROM AUTHOR]

A new type of incident in the form of a methane explosion caused by spontaneous combustion of coal is receiving more and more attention due to the high ground temperature and high methane content in coal mines. To investigate the formation process of this type of incidents and advance the research on methane explosion risk caused by spontaneous coal combustion, a self-designed experimental platform was used to determine the influence of spontaneous coal combustion on methane migration in the goaf. Additionally, the effect of different ventilation velocities at the mining face on methane migration in the goaf was studied. The results reveal that air leakage plays a key role in methane migration in the goaf. The bigger the ventilation velocity, the larger the area affected by air leakage. In addition, the superposition of the air leakage and the horizontal and vertical movement of hot gases creates the entrainment effect in the spontaneous combustion area. Eventually, the methane concentration at the location of spontaneous combustion is the lowest and it gradually increases outside the spontaneous combustion area because of the superposition of air leakage, 'fire pressure' and the entrainment effect. [ABSTRACT FROM AUTHOR]

Poly(acrylic acid-co-2-acrylamide-2-methyl-1-propanesulfonic acid)/kaolin hydrogel composite was synthesised using acrylic acid (AA), 2-acrylamide-2-methyl-1-propanesulfonic acid (AMPS) and kaolin (KL) as main materials. The composite was characterised and used to remove methyl orange (MO) from aqueous solutions. Effect of adsorption conditions, including initial concentration of MO, contact time, pH values and ionic strength, on the adsorption capacities was studied. Maximal adsorption capacity was 506 mg/g as the initial concentration of MO was 1000 mg/L. It showed that the adsorption process was spontaneous, and the isotherms and kinetics were in good agreement with the Freundlich isotherm model and pseudo-second-order equation, respectively. [ABSTRACT FROM AUTHOR]

Three novel 2-phenylthiazole derivatives were synthesised and characterised by spectroscopic techniques. The structure of the synthesised compounds was unambiguously confirmed by a single-crystal X-ray diffraction analysis of ethyl 2-(4-{[5-(4-benzylpiperidin-1-yl)pentyl]oxy}phenyl)thiazole-4-carboxylate. All of the compounds presented good cholinesterase-inhibition activities and ethyl 2-(4-{[5-(4-benzylpiperidin-1-yl)pentyl]oxy}phenyl)thiazole-4-carboxylate showed the best acetylcholinesterase-inhibition and butyrylcholinesterase-inhibition abilities with IC50 values of 5.19 µM and 5.83 µM. The docking study demonstrated that it could interact with both the catalytic active site (CAS) and the peripheral anionic site (PAS) of acetylcholinesterase and could chelate with metal ions like Cu2+ and Zn2+. [ABSTRACT FROM AUTHOR]

Coal dust is an increasingly serious problem in underground coal mines. This research developed and tested a novel dust prevention technology of surfactant-magnetized water that utilizes the synergy between magnetization and surfactants to markedly improve the wettability of water, resulting in better dust suppression than water sprays alone. The technology was systematically studied in laboratory and field conditions. A compound surfactant was developed as part of the new technology and was effective at low dosage (0.03wt%, approximately one-sixth that of conventional alternatives). The new surfactant exhibited excellent synergetic effects with magnetization, with reduced surface tension (28.07mNm-1, 7.2% lower than that of the original solution). A new type of magnetic apparatus was designed and formed the core of the novel dust suppression technology. The magnetic device produces a powerful and consistent magnetic field (300-350mT) to achieve effective magnetization of water flow. In field tests, the new technology increased respirable dust and total dust suppression efficiencies by 44.94% and 31.79%, respectively, compared to that of water spray. And the new technology effectively improves the atmosphere in mechanized underground coal mines, contributing to a safer and healthier working environment. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the differential expression and clinical significance of histone methyltransferase G9a, histone H3K9me2 and histone H3K9me1 in human brain glioma and adjacent tissue samples. It also aimed to observe the effect and mechanism of BIX-01294, as an inhibitor of methyltransferase G9a, on the proliferation, apoptosis, methylation of H3K9 and H3K27, and the acetylation in U251 glioma cells in vitro. The differential expression of methyltransferase G9a, histone H3K9me2 and histone H3K9me1 in in human brain glioma and adjacent tissues were analyzed by immunohistochemistry, a growth curve of U251 cells following treatment with BIX-01294 was determined using the MTT assay. In addition, the apoptosis percentage of U251 cells was analyzed by TUNEL assay and the expression levels of apoptosis-associated proteins, including B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), caspase-9 and caspase-3, and the acetylation of histones, including H3K27me1, H3K27me2 and H3 in U251 were analyzed by western blot following BIX-01294 treatment. The positive rate of G9a in glioma tissues was 86% (43/50), which was significantly different from 42% (21/50) in adjacent tissues (P<0.01). The positive rate of H3K9me2 in glioma tissues was 82% (41/50), which was significantly different from 38% (19/50) in adjacent tissues (χ2=18.38; P<0.01). The expression of G9a and H3K9me2 were associated with the World Health Organization (WHO) glioma grade. The positive rate of H3K9me1 in glioma tissues was 54% (27/50) and 44% (22/50) in adjacent tissues, though this result was not significantly different (χ2=1.21, P>0.05). BIX-01294 inhibited the proliferation of U251, downregulated expression of Bcl-2, and upregulated expression of Bax, caspase-3 and caspase-9, and induced apoptosis of U251. BIX-01294 downregulated H3K9me1, H3K9me2, H3K27me1 and H3K27me2, however, it did not affect the acetylation of H3K9me3 and H3. High expression of G9a and H3K9me2 in glioma tissue samples was associated with the WHO grade, which indicated that G9a and H3K9me2 may promote generation and development of glioma. BIX-01294 inhibited proliferation and induced apoptosis of glioma cells, changes in methylation of H3K9 and H3K27 resulting in conformational changes of chromosome may be an underlying mechanism. BIX-01294 may be a potential novel therapeutic agent in the treatment of glioma. [ABSTRACT FROM AUTHOR]

A vertically orientated ultrasonic transducer contained within a closed cylindrical Pyrex tube was used to study the acoustic streaming flow within a cylindrical container. A particle-image velocimetry (PIV) system incorporating fluorescent 1.5 µm seeding particles suspended in a mixture of diethyl-phthalate and ethanol, whose optical index was matched to that of Pyrex, was used to allow for undistorted PIV imaging within the Pyrex tube. Temperature on the end-wall surface and acoustic pressure within the cylinder were measured for different end-wall materials. Variables considered included acoustic absorption and reflection coefficients, ultrasound intensity, container height, and thermal properties of the end-wall material. It was observed that a quasi-steady flow field driven by acoustic streaming is rapidly established within the container, which is typically dominated by a stationary vortex ring with downward flow along the ring axis. After sufficient time this quasi-stationary flow exhibits a thermal instability causing it to transform into a secondary flow state. Different types of secondary flow states were observed, including cases where the flow along the cylinder axis is oriented upward toward the ultrasound transducer and cases where the axial flow changes directions along the cylinder axis. [ABSTRACT FROM AUTHOR]

Methane gas explosions and spontaneous combustion of coal severely threaten mining production safety and efficiency. Methane drainage can reduce the risk of a methane explosion while it may intensify the self-ignition of coal. To understand the relationship between these two issues, a working face of the Xinji No.2 Coal Mine in China was studied. A model of high drill holes extraction (HDHE) is established and the methane concentration distribution and air leakage under four different drainage pressures (below atmospheric) were determined. The simulation results show that drainage pressures can control the methane concentration in the air, so as not to exceed a threshold value. However, these drainage pressures enlarged the size of the zone where spontaneous combustion could occur due to the increase in air leakage. The possibility of the coexistence of a methane explosion and spontaneous coal combustion was proposed. This is an important index for the selection of a reasonable methane drainage pressure. The monitoring data from the mine were used to validate the model. [ABSTRACT FROM AUTHOR]

Immunosuppressed patients are at risk for developing Epstein-Barr Virus (EBV)-positive lymphomas that express the major EBV oncoprotein, LMP1. Although increasing evidence suggests that a small number of lytically infected cells may promote EBV-positive lymphomas, the impact of enhanced lytic gene expression on the ability of EBV to induce lymphomas is unclear. Here we have used immune-deficient mice, engrafted with human fetal hematopoietic stem cells and thymus and liver tissue, to compare lymphoma formation following infection with wild-type (WT) EBV versus infection with a "superlytic" (SL) mutant with enhanced BZLF1 (Z) expression. The same proportions (2/6) of the WT and SL virus-infected animals developed B-cell lymphomas by day 60 postinfection; the remainder of the animals had persistent tumor-free viral latency. In contrast, all WT and SL virus-infected animals treated with the OKT3 anti-CD3 antibody (which inhibits T-cell function) developed lymphomas by day 29. Lymphomas in OKT3-treated animals (in contrast to lymphomas in the untreated animals) contained many LMP1-expressing cells. The SL virus-infected lymphomas in both OKT3-treated and untreated animals contained many more Z-expressing cells (up to 30%) than the WT virus-infected lymphomas, but did not express late viral proteins and thus had an abortive lytic form of EBV infection. LMP1 and BMRF1 (an early lytic viral protein) were never coexpressed in the same cell, suggesting that LMP1 expression is incompatible with lytic viral reactivation. These results show that the SL mutant induces an "abortive" lytic infection in humanized mice that is compatible with continued cell growth and at least partially resistant to T-cell killing. [ABSTRACT FROM AUTHOR]

The broadband response of second harmonic generation (SHG) is experimentally observed in a two-dimensional (2D) quasi-random quasi-phase-matching (QPM) structure. A nonlinear conversion efficiency of more than 50% is obtained. Due to the line-type distribution of the reciprocal vector, the second harmonic wave (SHW) covering a broad frequency band is efficiently radiated in the shape of one single spot or three spots instead of a stripe. This is believed to be favorable for its practical application and paves the way for the use of ultrahigh-bandwidth light sources and devices in modern optical technologies. [ABSTRACT FROM AUTHOR]

Epstein-Barr virus (EBV) infects cells in latent or lytic forms, but the role of lytic infection in EBV-induced lymphomas is unclear. Here, we have used a new humanized mouse model, in which both human fetal CD34+ hematopoietic stem cells and thymus/liver tissue are transplanted, to compare EBV pathogenesis and lymphoma formation following infection with a lytic replication-defective BZLF1-deleted (Z-KO) virus or a lytically active BZLF1+ control. Both the control and Z-KO viruses established long-term viral latency in all infected animals. The infection appeared well controlled in some animals, but others eventually developed CD20+ diffuse large B cell lymphomas (DLBCL). Animals infected with the control virus developed tumors more frequently than Z-KO virus-infected animals. Specific immune responses against EBV-infected B cells were generated in mice infected with either the control virus or the Z-KO virus. In both cases, forms of viral latency (type I and type IIB) were observed that are less immunogenic than the highly transforming form (type III) commonly found in tumors of immunocompromised hosts, suggesting that immune pressure contributed to the outcome of the infection. These results point to an important role for lytic EBV infection in the development of B cell lymphomas in the context of an active host immune response. [ABSTRACT FROM AUTHOR]

With dexamethasone as the model drug and polycaprolactone (PCL) as the carrier material, a drug delivery coating for cochlear electrodes was prepared, to control cochlear fibrosis caused by cochlear implantation. A dexamethasone/poly (e-caprolactone)-based electrode coating was prepared using the impregnation coating method. Preparation parameters were optimized, yielding 1 impregnation instance, impregnation time of 10 s, and PCL concentration of 10%. The coating was characterized in vitro using scanning electron microscopy, a universal machine, high-performance liquid chromatography, and CCK-8. The surface was porous and uniformly thick (average thickness, 48.67 mm)--with good flexibility, long-term slow drug release, and optimal drug concentration--and was biologically safe. The experimental results show that PCL is an ideal controlled-release material for dexamethasone as a drug carrier coating for cochlear implants. [ABSTRACT FROM AUTHOR]

Chronic rhinosinusitis (CRS) is a rather prevalent condition with a chronic inflammatory process, which is hard to cure. Herein, a new antibacterial drug, nitric oxide (NO), was used for the attempt on CRS therapy. To achieve this, a star copolymer (b-CD-PAMAM) consisting of the b-cyclodextrin (b-CD) core and seven PAMAM-G3 arms, which was designed as a low-cytotoxicity and high NO loading carrier, were synthesized and characterizied. The obtained b-CD-PAMAM/NONOate showed the effect in inhibiting and dispersing the biofilm of S. aureus, as well as the effective antibacterial performance, implying the promising application in CRS treatment. The in vivo assay confirmed that b-CD-PAMAM/NONOate displayed excellent therapy effect on CRS and significantly improved the symptoms of the experimental rats, which was no significant different in therapy effect with the clinical Rhinocort. Incorporated with its little toxicity in vitro and in vivo, the b-CD-PAMAM/NONOate was suggested a promising application in CRS therapy. [ABSTRACT FROM AUTHOR]

An effective strategy was developed to fabricate the supramolecular hydrogels with high mechanical strength and adjustable thermosensitivity in aqueous systems, in which physical hydrogel precursors were first formed by the inclusion complexation of Pluronic F68/poly(-caprolactone) block copolymer end-capped with acryloyl groups with -cyclodextrin (-CD) and subsequently in situ UV photo-cross-linking was carried out. In this way, strong supramolecular hydrogels with elastic moduli greater than 100 000 Pa could be created, which is an order of magnitude higher than that previously achieved with related supramolecular hydrogels. Moreover, the stimuli-responsive property of these hydrogels could be tailored by changing the molar feed ratio of -CD to the macromer. By X-ray diffraction and thermogravimetric analyses, the polypseudorotaxane structure of the inclusion complexes in as-obtained hydrogels was confirmed. [ABSTRACT FROM AUTHOR]

On the basis of the synthesis of water-soluble poly(-caprolactone)−poly(ethylene glycol)−poly(-caprolactone) (PCL-PEG-PCL) block copolymers, the supramolecular hydrogels were fabricated rapidly in aqueous solutions by their inclusion complexation with -cyclodextrin. X-ray diffraction (XRD) analyses confirmed the supramolecular self-assemblies of -cyclodextrin threaded onto amphiphilic PCL−PEG−PCL block copolymers. The resulting hydrogels display a high degree of elasticity, with the storage modulus (G‘) greater than the loss modulus (G‘ ‘) over the entire range of frequency. Moreover, their viscosity greatly diminished as they were sheared. By controlling the molecular weight of the PEG component in the block copolymers and the content of the block copolymer, their rheological properties could be modulated. Such hydrogel materials have the potential to be used as tissue engineered scaffolds, biosensors in the human body, and carriers for controlled drug delivery. [ABSTRACT FROM AUTHOR]

Calculations of elastic constants and development of elastic anisotropy under uniaxial compression in originally isotropic polycrystalline LaCoO3 perovskite are reported. The lattice strains in individual (hkl) planes as well as average lattice strain were determined both for planes oriented perpendicular and parallel to the loading direction using in-situ neutron diffraction. Utilizing average lattice strains as well as lattice strains along the a and c crystallographic directions, an attempt was made to determine Poisson's ratio of LaCoO3, which was then compared with that measured using an impulse excitation technique. The elastic constants were calculated and Young's moduli of LaCoO3 single crystal in different crystallographic directions were estimated. [ABSTRACT FROM AUTHOR]

The dynamics of texture formation, changes in crystal structure, and stress accommodation mechanisms have been studied in perovskite-type R3c rhombohedral LaCoO3 during uniaxial compression using in-situ neutron diffraction. The in-situ neutron diffraction revealed the complex crystallographic changes causing the texture formation and significant straining along certain crystallographic directions during compression, which are responsible for the appearance of hysteresis and non-linear ferroelastic deformation in the LaCoO3 perovskite. The irreversible strain after the first loading was connected with the appearance of non-recoverable changes in the intensity ratio of certain crystallographic peaks, causing non-reversible texture formation. However, in the second loading/unloading cycle, the hysteresis loop was closed and no further irrecoverable strain appeared after deformation. The significant texture formation is responsible for an increase in the Young's modulus of LaCoO3 at high compressive stresses, ranging from 76 GPa at the very beginning of the loading to 194 GPa at 900 MPa at the beginning of the unloading curve. [ABSTRACT FROM AUTHOR]