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A nanoparticle of cobalt(II) coordination polymer (CP), [Co(L)(npht)] n ( 1 ) (H 2 npht = 4-nitrophthalic acid, L = 1,3-bis(5,6-dimethylbenzimidazol-1-ylmethyl)benzene) and its nanocomposite (Ag/CP 1 ) were obtained by the sonochemical approach and characterized by IR, elemental analysis, thermogravimetric analyses (TGA), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and X-ray powder diffraction (XRPD). CP 1 shows a 1D double chain containing two different helical chains, which is further extended into a two-dimensional supramolecular framework by C–H⋯O hydrogen bonding interactions. The photoluminescence properties and photocatalytic properties of the nanoparticles of CP 1 and Ag/CP 1 on the degradation of methylene blue (MB) were investigated, Ag/CP 1 exhibited excellent photocatalytic activity under UV and visible light, which can be attributed to the strong interactions between Ag nanorods and CP 1 , which lead to electron–hole pair separation between Ag nanorods and CP 1 . In addition, the photocatalytic mechanism is also carried out by introducing t -butyl alcohol (TBA) as a widely used ·OH scavenger. The influence of ultrasound irradiation time and power on the morphology and size of the nanostructure CP 1 were studied. The results indicated that a decrease in time and an increase in power led to a decrease of particle size. [ABSTRACT FROM AUTHOR]

A 2D cobalt(II) chiral coordination polymer (CP), namely [Co(bimb)(tbip)]n (1) (bimb = 4,4′-bis(imidazol-1-ylmethyl)biphenyl and Htbip = 5-tert-butylisophthalic acid) containing tri-flexural helix structures has been hydrothermally synthesized and structurally characterized. CP 1 features a 2D (4,4) layer, which is further extended into a 3D supramolecular framework through weak hydrogen bonding interactions. Intermolecular interactions in the crystal framework have been analyzed by Hirshfeld surface and fingerprint plots in detail. The thermogravimetric analyses (TGA), luminescence, and electrochemical properties of CP 1 have been investigated. Furthermore, CP 1 exhibits promising photocatalytic activities for the degradation of methylene blue (MB) under UV irradiation with the degradation efficiency is up to 96.7%. [ABSTRACT FROM AUTHOR]

Purpose: To study the effectiveness of various nonsteroidal anti-inflammatory drugs (NSAIDs) in patients with vertebral fractures. Methods: A total of 78 patients (17 males and 61 females) with a mean age of 69.5 years were included. The major inclusion criterion was an osteoporotic vertebral fracture between T7 and L3. The exclusion criteria included fractures above T7 and below L3; and other bone disorders such as disc herniation, spondylolisthesis, an infection, or a tumour. Pain intensity was assessed with the aid of a 10-point visual analogue scale (VAS). Bone mineral density (BMD) data, delay in reunion, and any other matter of significance, were discussed with the treating doctors and cross-checked with independent doctors. The NSAIDs given were non-selective cyclo-oxygenase (COX) inhibitors (naproxen, indomethacin and flurbiprofen) and selective COX 2 inhibitors (piroxicam, celecoxib, and rofecoxib). All data were compiled and appropriately analysed. Results: Some NSAIDs interfered with bone healing. No male required surgery, but two females taking naproxen, one taking flurbiprofen, and another taking celecoxib, required surgery. In terms of bone healing, non-union and delay in reunion were more evident in those taking naproxen, indomethacin or flurbiprofen than in those taking piroxicam, celecoxib, or rofecoxib. All T scores were lower than -2.5, indicating that all the patients were osteoporotic. Positive changes in T scores after 12 weeks were evident only in those taking rofecoxib, celecoxib, or piroxicam. VAS scores were also better in these patients. Conclusions: Celecoxib seems to be the best of the six NSAIDs in terms of both analgesia and bone health. The study recommends the use of celecoxib in patients with vertebral fractures. [ABSTRACT FROM AUTHOR]

The development of materials with highly selective recognition towards Hg2+ is of great significance in environmental monitoring. Herein, a novel thermo-responsive copolymer with Hg2+ recognition property is prepared via thermally-initiated copolymerization of 5′-O-Acryloyl 5-methyl-uridine (APU) and N -isopropylacrylamide (NIPAM). The chemical structure and stimuli-sensitive properties of poly(N -isopropylacrylamide- co -5-methyl-uridine) (P(NIPAM- co -APU)) linear polymers and hydrogel are thoroughly investigated. At the supramolecular level, P(NIPAM- co -APU) linear polymers could respond to both temperature and Hg2+ stimuli with highly selective recognition towards Hg2+ over other 18 metal ion species (at least 5 fold difference) and common anions. Upon capturing Hg2+ by APU units as host metal receptors, the lower critical solution temperature (LCST) of P(NIPAM- co -APU, PNU-7 and PNU-11) linear polymers are significantly shifted more than 10 °C due to the formation of stable APU -Hg2+- APU directed host-guest complexes. Accordingly, at the macroscopic level, P(NIPAM- co -APU) hydrogel display selective and robust recognition of Hg2+ under optimum conditions, and its maximum Hg2+ uptake capacity was 33.1 mg g−1. This work provides a new option for Hg2+ recognition with high selectivity, which could be facilely integrated with other smart systems to achieve satisfactory detection of environmental Hg2+. [Display omitted] • Thermo and ion-responsive polymers were synthesized by copolymerization of APU and NIPAM. • The linear copolymers have a highly selective recognition of mercury ions. • The different stabilities of divers metal-mediated base-pairs were rationalized by theoretical calculation. • The hydrogels can be recycled for highly selective recognition of mercury ions. [ABSTRACT FROM AUTHOR]

This work aims to analyze the electrospray ionization multistage mass spectrometry (ESI-MSn) fragmentation characteristics of hydroxycinnamic acids (HCAs) in negative ion mode. The geometric parameters, energies, natural bond orbitals and frontier orbitals of fragments were calculated by density functional theory (DFT) to investigate mass spectral fragmentationmechanisms. The results showed that proton transfer always occurred during fragmentation of HCAs; their quasi-molecular ions ([M - H]-) existed inmore than one form and weremainlywith the lowest energy. The fragmentation characteristics included the followings: (1) according to the different substitution position of phenolic hydroxyl group, the ring contraction reaction by CO elimination from benzene was in an increasingly difficult order: m-phenolic hydroxyl > p-phenolic hydroxyl > o-phenolic hydroxyl; and (2) ortho effect always occurred in o-dihydroxycinnamic acids (o-diHCAs), i.e. one phenolic hydroxyl group offered H+, which combined with the other one to lose H2O. In addition, there was a nucleophilic reaction during ring contraction in diHCAs that oxygen atom attacked the carbon atom binding with the other phenolic hydroxyl to lose CO2. The fragmentation characteristics andmechanismof HCAs could be used for analysis and identification of such compounds quickly and effectively, and as reference for structural analogues by ESI-MS. [ABSTRACT FROM AUTHOR]

Eight new species of the genus Diplectrona occurring in China are described and diagnosed. Photos of cephalic setal warts, anterodorsal filament of sternum V, internal sacs within segment V and within VII and VIII are presented and the male genitalia are illustrated. Based on cephalic setal warts and male genitalia, two new species groups are established. The Diplectrona jiaolinga diagnostic species group is diagnosed to include D. jiaolinga n. sp., D. quadrivalvis n. sp., and D. delta n. sp. The Diplectrona coalescens diagnostic species group is diagnosed to include D. coalescens n. sp. and D. guangxiensis n. sp. Three new species, D. wangyipingi n. sp., D. tetraphylla n. sp. and D. tuberculiformis n. sp. cannot be presently placed in any species group ( incertae sedis). [ABSTRACT FROM AUTHOR]

Three supramolecular coordination polymers, namely [Ni(L1)(DCTP)(HO)] (1), [Cu(L2)(DCTP)] (2), [Co(L3)(DCTP)] (3) (L1 = 1,5-bis(5,6-dimethylbenzimidazole)pentane, L2 = 1,4-bis(5,6-dimethylbenzimidazole)butane, L3 = 1,4-bis(benzimidazole)-2-butylene) have been hydrothermally synthesized and characterized by single crystal X-ray structure determination, FT-IR, elemental analysis, X-ray powder diffraction (XPD), and thermogravimetric analysis (TGA). CP 1 exhibits 2D 6 honeycombed network structure, which is further extended into a 3D Moganite ( mog) supramolecular framework by classical O-H⋯O hydrogen-bonding interaction. CPs 2 -3 present 2D (4,4) layers, and 3D supramolecular frameworks that are formed by π- π stacking interactions. Furthermore, the catalytic activities of CPs 1-3 for the degradation of methyl orange in a Fenton-like process has been investigated, and CPs 1-3 show strong photoluminescence properties at room temperature in solid state. [ABSTRACT FROM AUTHOR]

Three zinc(II) coordination polymers (CPs), {[Zn(L) 0.5 (tbta)]·0.5 L·2.5H 2 O} n ( 1 ), {[Zn(L) 0.5 (mip)]·H 2 O} n ( 2 ) and {[Zn(L) 0.5 (npht)(H 2 O)]·0.5H 2 O} n ( 3 ) (L = 1,4-bis(thiabendazole)butane, H 2 tbta = tetrabromoterephthalic acid, H 2 mip = 5-methylisophthalic acid, H 2 npht = 3-nitrophthalic acid) have been hydrothermally synthesized and structurally characterized. Single-crystal X-ray diffraction analyses reveal that CP 1 shows a 2D honeycomb-like (6, 3) network. CP 2 displays a hybrid helical chain, and further assembled into a 2D supramolecular layer via weak C H⋯O hydrogen bonding interactions, whereas CP 3 is a right-handed helical chain and finally extended into a 3D supramolecular structure by classical O H⋯O hydrogen bonds and π – π stacking interactions. Further, the Hirshfeld surfaces, fingerprint plots, fluorescence properties and catalytic performances of three CPs for the degradation of methyl orange dye in a Fenton-like process have been investigated. [ABSTRACT FROM AUTHOR]

Background and purpose Astragalus membranaceus (AM) is the first-choice herb for fatigue treatment in traditional Chinese medicine and the main herb used for stroke treatment in China and Taiwan. The purpose of this study was to evaluate the effect of AM on poststroke fatigue (PSF). Materials and methods This study was designed as a double-blind, randomized, controlled preliminary study. Sixty-four patients with PSF were assigned to treatment group (TG; 31 patients), which received oral administration of AM (2.8 g three times per day) for 28 days, and a control group (CG; 33 patients), which received a placebo. The primary outcome measures were the changes in the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) and Brief Fatigue Index (BFI) scores Results A total of 61 patients (29 patients in the TG and 32 patients in the CG) completed the trial. The difference in BFI scores between Visit 2 and Visit 1 was –17.83±17.70 in the TG, which was greater than that in the CG (–8.03±9.95; p =0.01); additionally, the difference in BFI scores between Visit 3 and Visit 1 was –16.48±16.41 in the TG, which was also greater than that in the CG (–9.47±13.39; p =0.05). In the EORTC QLQ-C30, the difference in cognitive functioning scores between Visit 2 and Visit 1 was 14.37±13.89 in the TG, which was greater than that in the CG (3.65±19.74; p =0.02); additionally, the difference in these scores between Visit 3 and Visit 1 was 14.37±16.50 in the TG, which again was greater than that in the CG (6.25±19.74; p =0.04). The difference in social functioning scores between Visit 3 and Visit 1 was 9.77±15.12 in the TG, which was greater than that in the CG (–1.56±20.46; p =0.01). The difference in global quality of life (QOL) scores between Visit 2 and Visit 1 was 14.08±18.78 in the TG, which was also greater than that in the CG (1.56±18.14; p =0.003); moreover, the difference in these scores between Visit 3 and Visit 1 was 10.92±17.55 in the TG, and this was greater than that in the CG (1.82±15.8; p =0.05). Conclusion AM can improve BFI scores; cognitive functioning, social functioning, and global QOL scores in the EORTC QLQ-C30. Our results suggest that physicians should pay close attention to the unmet medical needs of patients with PSF. AM is helpful for treating patients with PSF; however, additional studies with a larger sample and a longer period of investigation are required. [ABSTRACT FROM AUTHOR]

To eliminate the negative impacts of pollutants in wastewater (such as suspended solids, excess N, P, heavy metals) on microalgae growth, an annular ion-exchange-membrane photobioreactor (IEM-PBR) was proposed in this study. The IEM-PBR could avoid direct mixing of algae cells with wastewater by separating them into two chambers. In the IEM-PBR, the nutrients (mainly N and P) in wastewater continuously permeated into microalgae cultures through the ion-exchange-membrane for microalgae growth, while the pollutants hardly permeated into microalgae cultures. Three types of representative wastewater were investigated to evaluate the performance of the IEM-PBR. When cultivated with wastewater containing excess nutrients, high turbidity and excess heavy metals, microalgae biomass concentrations were significantly improved from 2.34, 2.15 and 0 g L −1 in the traditional PBR to 4.24, 3.13 and 2.04 g L −1 in the IEM-PBR. Correspondingly, the removal efficiencies of N and P in wastewater were also greatly improved by using the IEM-PBR. [ABSTRACT FROM AUTHOR]

A simple one-pot method was developed to prepare PtNi alloy nanoparticles, which can be self-decorated on multiwalled carbon nanotubes in [BMIm][BF] ionic liquid. The nanohybrids are targeting stable nanocatalysts for fuel cell applications. The sizes of the supported PtNi nanoparticles are uniform and as small as 1-2 nm. Pt-to-Ni ratio was controllable by simply selecting a PtNi alloy target. The alloy nanoparticles with Pt-to-Ni ratio of 1:1 show high catalytic activity and stability for methanol electro-oxidation. The performance is much higher compared with those of both Pt-only nanoparticles and commercial Pt/C catalyst. The electronic structure characterization on the PtNi nanoparticles demonstrates that the electrons are transferred from Ni to Pt, which can suppress the CO poisoning effect. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A novel self-adaptive microalgae photobioreactor using anion exchange membranes (AEM-PBR) for continuous supply of nutrients was proposed to improve microalgae biomass production. The introduction of anion exchange membranes to the PBR can realize continuous supply of nutrients at desired rates, which is beneficial to the growth of microalgae. The results showed that the maximum biomass concentration obtained in the AEM-PBR under continuous supply of nitrogen at an average rate of 19.0 mg N/L/d was 2.98 g/L, which was 129.2% higher than that (1.30 g/L) in a PBR with all the nitrogen supplied in batch at initial. In addition, the feeding rates of nitrogen and phosphorus were optimized in the AEM-PBR to maximize biomass production. The maximum biomass concentration of 4.38 g/L was obtained under synergistic regulation of nitrogen and phosphorus feeding rates at 19.0 mg N/L/d and 4.2 mg P/L/d. The AEM-PBR demonstrates a promising approach for high-density cultivation of microalgae. [ABSTRACT FROM AUTHOR]

A novel self-adaptive microalgae photobioreactor using anion exchange membranes (AEM-PBR) for continuous supply of nutrients was proposed to improve microalgae biomass production. The introduction of anion exchange membranes to the PBR can realize continuous supply of nutrients at desired rates, which is beneficial to the growth of microalgae. The results showed that the maximum biomass concentration obtained in the AEM-PBR under continuous supply of nitrogen at an average rate of 19.0 mg N/L/d was 2.98 g/L, which was 129.2% higher than that (1.30 g/L) in a PBR with all the nitrogen supplied in batch at initial. In addition, the feeding rates of nitrogen and phosphorus were optimized in the AEM-PBR to maximize biomass production. The maximum biomass concentration of 4.38 g/L was obtained under synergistic regulation of nitrogen and phosphorus feeding rates at 19.0 mg N/L/d and 4.2 mg P/L/d. The AEM-PBR demonstrates a promising approach for high-density cultivation of microalgae. [ABSTRACT FROM AUTHOR]

The poor bacteriostasis and osseointegration properties of bioinert polyetheretherketone (PEEK) hinder its clinical application. This work reports a simple and versatile strategy for fabricating dual-functional coating with programmed sequential drug release properties on porous PEEK surfaces. The dual-drug-loaded composite coating composed of drug-loaded poly(lactic- co -glycolic acid) (PLGA) nanoparticles and drug-loaded polyvinyl alcohol (PVA) gel can be immobilized on the surface of sulfonated PEEK by a cyclic freeze-thaw method. Based on the swelling of PVA and the slow degradation of PLGA, the composite coating can realize rapid release of antibacterial drugs and sustained release of osteogenic drugs. The in vitro antibacterial evaluations show that the porous PEEK modified with drug-loaded composite gel coating exhibits an early effective fight against Staphylococcus aureus (S.aureus). The results of in vitro cell experiments show that the PEEK materials modified by the composite gel coating can well support the normal growth, adhesion and proliferation of cells. In addition, the PEEK material coated with the drug-loaded composite gel is found to have positive effects on the osteogenic differentiation of cells in detections of alkaline phosphatase (ALP) activity of cells and the amount of calcium deposition on the surface of the material. The results demonstrate that the proposed porous PEEK modified with dual-drug-loaded composite gel coating simultaneously exhibits excellent osseointegration and exerts early effective antibacterial activity. This dual-functional PEEK material has great application potential in clinical bone tissue repair. [Display omitted] • A dual-drug-loaded composite gel coating is constructed on the PEEK surface. • The composite coating can realize programmed sequential drug release. • Antibacterial drug is rapidly released and osteogenic drug is sustainedly released. • The coating is composed of drug-loaded PLGA nanoparticles and drug-loaded PVA gel. • The modified PEEK exhibits excellent osseointegration and antibacterial activity. [ABSTRACT FROM AUTHOR]

Clonorchiasis is caused by the ingestion of raw freshwater fish and causes high burden in East Asia. The epidemiological profiles and determinants of C. sinensis infection, knowledge, practice and attitude related to clonorchiasis were demonstrated in Hengxian county, Guangxi, China. The overall prevalence of C. sinensis was 60.3%, which was higher in male than in female and in elder population compared to children. The percentage knowing local transmission, transmission route and harm of C. sinensis was 20.9%, 31.4% and 32.5%. A percentage of 60.4% reported ingestion of raw freshwater fish, while 70.1% persons would like to accept treatment if infected with C. sinensis. Of the individuals ingesting raw freshwater fish, 82.0% did at home and 81.3% drunk alcohol when ingesting raw freshwater fish. Sixty-two percent showed the persistence on ingestion of raw freshwater fish in future. The ingestion of raw freshwater fish varied by seasons, with a proportion of 57.8% in spring, 48.3% in summer, 60.2% in autumn and 92.2% in winter. In multivariable regression models, age groups, history with C. sinensis treatment, and frequency on ingesting raw freshwater fish were related to C. sinensis infection, while gender, educational level, history with C. sinensis infection, and knowing local transmission were related to the practice of ingesting raw freshwater fish. Gender, history with C. sinensis treatment, frequency on ingesting raw freshwater fish, duration of ingesting raw freshwater fish and drinking alcohol when ingesting raw freshwater fish were associated to the attitude to the ingestion of raw freshwater fish in future. Great efforts are needed to combat clonorchiasis, in which the heterogeneity of population in knowledge, practice, attitude and infection needs to be considered. Men are of crucial importance in term of the morbidity control through chemotherapy. Meanwhile, massive education is expected to implement, which needs to promote the change of ingesting raw freshwater fish for sustainable control of clonorchiasis. [ABSTRACT FROM AUTHOR]

Two Ni(II) coordination polymers, namely {[Ni(L1)(2,6-ndc)(HO)]·0.5(2,6-ndc)·2HO} ( 1) and [Ni(L2)(1,4-ndc)(HO)] ( 2) (L1 = 1,3-bis(5,6-dimethylbenzimidazol-1-yl)-2-propanol, L2 = 1,3-bis(5,6-dimethylbenzimidazol-1-ylmethyl)benzene, 2,6-Hndc = 2,6-naphthalenedicarboxylic acid and 1,4-Hndc = 1,4-naphthalenedicarboxylic acid) have been synthesized under hydrothermal conditions and structurally characterized by elemental analyses, thermogravimetric analysis, IR spectra, and single crystal X-ray diffraction. CP- 1 presents a 1D zigzag chain, and CP- 2 features a 1D tube-like chain. Both one-dimensional coordination polymers are further extended into 3D and 2D supramolecular framework via classical O-H···O hydrogen bondings, respectively. Moreover, the catalytic properties of the two complexes for the degradation of Methyl orange in a Fenton-like reaction are discussed. Graphical Abstract: [ABSTRACT FROM AUTHOR]

A black TiO2 nanotube (NT) heterostructure with an anatase-core and an amorphous-shell has been synthesized by NH3 annealing of amorphous NT grown by the anodization of a Ti substrate. Remarkable photoabsorption behavior of these black TiO2 NTs is observed: strong absorption throughout the entire optical wavelength region from ultraviolet to near-infrared. X-ray absorption near-edge structure (XANES), X-ray photoelectron spectroscopy (XPS) and resonant inelastic X-ray scattering (RIXS) have been used to elucidate the origin of this spectacular light capture phenomenon. Surface-sensitive XANES recorded in total electron yield and XPS show that the surface layer is amorphous with a chemical composition approaching that of Ti4O7. Bulk-sensitive XANES using X-ray partial fluorescence yield and Ti 2p RIXS confirm the presence of a rich amount of Ti3+ in the crystalline bulk (core of the NT with anatase structure) of black TiO2 NTs, which exhibits a dispersive d-d energy loss at ∼2 eV corresponding to the broad visible light absorption at ∼600 nm. Our results suggest that the extraordinary photoabsorption behavior of these black TiO2 NTs is due to the stabilization of Ti3+ in this special N-doped core-shell assembly having structure varying between TiO2 (bulk anatase) and Ti4O7 (surface, amorphous). [ABSTRACT FROM AUTHOR]

Understanding and optimizing the microalgae growth process is an essential prerequisite for effective CO 2 capture using microalgae in photobioreactors. In this study, the kinetic characteristics of microalgae Chlorella vulgaris growth in response to light intensity and dissolved inorganic carbon (DIC) concentration were investigated. The greatest values of maximum biomass concentration ( X max ) and maximum specific growth rate ( μ max ) were obtained as 2.303 g L −1 and 0.078 h −1 , respectively, at a light intensity of 120 μmol m −2 s −1 and DIC concentration of 17 mM. Based on the results, mathematical models describing the coupled effects of light intensity and DIC concentration on microalgae growth and CO 2 biofixation are proposed. The models are able to predict the temporal evolution of C. vulgaris growth and CO 2 biofixation rates from lag to stationary phases. Verification experiments confirmed that the model predictions agreed well with the experimental results. [ABSTRACT FROM AUTHOR]

Pd and PdAu nanoparticles stabilized on multi-walled carbon nanotubes are synthesized by simple metal sputtering onto nanotubes dispersed in ionic liquids. The nanoparticles are as small as about 2 nm and possess bare surface without capping agents. The surface density of the nanoparticles can be controlled by tuning the sputtering conditions, while the sizes of the nanoparticles remain very similar. The supported Pd/PdAu nanoparticles are highly catalytically active for reduction of 4-nitrophenol, and an activity factor up to 205 s −1 g −1 is achieved. The PdAu bimetallic nanoparticles show superior catalytic performance than the Pd monometallic counterparts, indicating the synergistic effects of Pd and Au. The present approach has the merit of making alloyed nanocatalysts as simple as making corresponding elementary ones. [ABSTRACT FROM AUTHOR]

The in situ hydrothermal reaction of CuI, NaN 3 and 4-(1H-imidazol-1-yl)benzonitrile leads to a new three-dimensional pillared-layer Cu(I)-MOF, [Cu 2 ( μ 3 -I)( μ 5 -IPT)] n ( 1 ) (HIPT = 5-[4-(imidazol-1-yl)phenyl]tetrazolate). Interestingly, the structure of 1 exhibits an unprecedented binodal (4, 8)-connected three-dimensional self-penetrating framework first constructed from [Cu 4 I 2 ] 2 + cationic clusters as 8-connected nodes and in situ generated IPT ligands as 4-connected nodes. Moreover, 1 is strongly luminescent with green emission ( λ em = 545 nm) in the solid-state. [ABSTRACT FROM AUTHOR]

This manuscript investigates the strength reduction factor of single degree of freedom system with constant ductility performance subjected to the mainshock-aftershock sequence-type ground motions. The recorded and artificial sequence-type ground motions are used. The aftershock ground motions in sequence are scaled to have different relative intensity levels. Four hysteretic models are used to simulate the different type of structures. The effects of period, ductility factor, site condition, aftershock, hysteretic behavior and damping are studied statistically. The results indicate that the strong aftershock ground motion has more obvious influences on strength reduction factors in short period region than on those in long period region. The degrading behavior would decrease the strength reduction factor of structure with short period at a magnitude of <20 %, while it would increase that of structure with medium-long period at a maximum level of 20 %. Finally, a predictive model, incorporating the effect of aftershock, is proposed to determine the strength reduction factor in the seismic design. [ABSTRACT FROM AUTHOR]

The effects of masonry infill walls on the behaviour of reinforced concrete frames are often ignored in seismic engineering. A three-dimensional non-linear finite-element model is introduced in this paper to simulate in-plane and out-of-plane behaviour of masonry infilled reinforced concrete frames. It employs a surface-based cohesive contact model to capture the crack and slide failure mode of the infill wall mortar joints. Comparison with experimental data shows that the proposed numerical model provides good estimates of the strength, deformation and failure modes in both directions. Several two-way numerical tests are conducted to investigate the interaction of in-plane and out-of-plane responses. The tests include sequential out-of-plane and in-plane loading (and vice versa) as well as simultaneous application of both loadings. The results indicate that out-of-plane performance and in-plane strength are significantly decreased by the interaction of loadings in two directions. The out-of-plane loading causes the out-of-plane failure mode, which is often seen in past earthquake events, and before which the in-plane strength is not fully developed. A mathematical expression is proposed for engineering analysis. [ABSTRACT FROM AUTHOR]

A large mainshock may trigger numerous aftershocks within a short period, and nuclear power plant (NPP) structures have the probability to be exposed to mainshock–aftershock seismic sequences. However, the researchers focused on seismic analyses of reinforced concrete containment (RCC) buildings under only mainshocks. The aim of this paper is to thoroughly investigate the dynamic responses of a RCC building under mainshock–aftershock seismic sequences. For that purpose, 10 as-recorded mainshock–aftershock seismic sequences with two horizontal components are considered in this study, and a typical three-dimensional RCC model subjected to the selected as-recorded seismic sequences is established. Peak ground accelerations (PGAs) of mainshocks equal to 0.3 g (safe shutdown earthquake load-SSE load) are considered in this paper. The results indicate that aftershocks have a significant effect on the responses of the RCC in terms of maximum top accelerations, maximum top displacements and accumulated damage. Furthermore, in order to preserve the RCC from large damage under repeated earthquakes, local damage and global damage indices are suggested as limitations under only mainshocks. [ABSTRACT FROM AUTHOR]

TiO-supported PdAu bimetallic nanoparticles (NPs) with small size and good dispersity were prepared by the room-temperature ionic liquid-assisted bimetal sputtering, which is simple, environmentally friendly, and free of additives and byproducts. Pd/Au atomic ratio can be tuned by controlling the sputtering conditions simply. High catalytic activity was found in PdAu-NPs-TiO hybrids for solvent-free selective oxidation of 1-phenylethanol using O as the oxidant at the low temperature of 50 °C and low pressure of 1 atm. It was found that Pd/Au ratio strongly affected the catalytical activity, and the highest conversion of about 35 % and turnover frequency of about 421 h were achieved at 1:1 of Pd/Au atomic ratio. The synergistic effect in PdAu NPs was also discussed based on the comprehensive characterization results. The present approach may offer an alternative platform for future development of green-chemistry compatible bimetallic nanocatalysts. [ABSTRACT FROM AUTHOR]

Borate and phosphate modified carbon nanotubes with different loading amounts are synthesized by a facile impregnation method and used as metal-free catalyst for oxidative dehydrogenation of isopentane. When the loading of borate was less than 5 wt% B 2 O 3 decrease in isopentane conversion and increase in alkene selectivity was observed, whereas with increase in borate loading exceeding 5 wt% B 2 O 3 the conversion and selectivity remain constant. This phenomenon is significantly different from the volcanic distribution of dehydrogenation selectivity of the phosphate modified carbon nanotubes. We propose that borate modification is more selective than phosphate modification toward the blockage of defects and the inhibition of combustion reaction on the CNTs supported by X-ray photoelectron spectroscopy, temperature-programmed desorption and oxidation. The synergetic effect of borate and phosphate has not been observed in the isopentane oxidative dehydrogenation. [ABSTRACT FROM AUTHOR]

Background: Enterobius vermicularis infection is a prevalent intestinal parasitic disease in children. In this study, we explored the epidemiological status and risk factors for E. vermicularis infection in children in southern China. Methods: A cross-sectional survey was carried out in Gaozhou city, Guangdong province, China, in December 2011. Children aged 2-12 years from five schools participated in the study. The adhesive cellophane-tape perianal swab method was applied to detect E. vermicularis infection, while a questionnaire was sent to each child's guardian(s) to collect demographic and socioeconomic data, as well as hygiene behaviors, pertaining to each child. Univariate and multivariate logistic regression analyses were performed to capture the potential risk factors. Results: Out of the 802 children surveyed, 440 were infected with E. vermicularis, with an average prevalence of 54.86%, and a range from 45.96 to 68.13%. The age variable was found to be statistically significant, whereas the sex variable was not. It was found that a mother's education level (low) and not washing hands before dinner were major risk factors in all children (802). After stratification by age, a father's education level (primary or below) and biting pencils (or toys) were significant risk factors in the younger children (508), while not washing hands before dinner and playing on the ground were important risk factors in the older children (294). Conclusion: This study demonstrates the prevalence of E. vermicularis infection in children in Gaozhou and reveals underlying risk factors. Most importantly, it reveals that risk factors differ among the different age groups, which indicates that different control measures targeted at particular age groups should be implemented. [ABSTRACT FROM AUTHOR]

Time-shifted TV has become one of the typical multimedia businesses. It has a variety of functions but the operations are more complex. Since the existing tests do not fully consider the interactions of parameters in the system, it is very difficult to find certain functional defects and failures. We apply the adaptive combinatorial testing methodology to Set-Top Box time-shifted T V business testing. Firstly we establish a combinatorial testing model, then we design and execute test cases and locate the faults exposed in the testing. The empirical study not only validates the existing combinatorial testing theories and methods, but also finds many real failures in the Set-Top Box time-shifted TV business. [ABSTRACT FROM AUTHOR]

A copper cyanide coordination polymer [Cu8(CN)8(bbtz)2] n ( 1) [bbtz = 1,4-bis(1,2,4-trizal-1-ylmethyl)benzene] was synthesized following a synchronous redox and self-assembly reaction under the solvothermal condition, and characterized by elemental analysis, infrared spectroscopy, and single-crystal X-ray diffraction. Interestingly, complex 1 exhibits a two-dimensional conjugated pillared double-layer architecture and an unprecedented (3,3,4)-connected network with the point symbol (6.7.10)2(6.72)2(62.73.10) topology. Moreover, the thermogravimetric analysis indicates complex 1 has highly thermal stability, and the solid-state emission spectrum for its crystalline material displays a strong green luminescence band ( λmax = 565 nm) at room temperature. The electrochemical behavior of complex 1 is determined by the scan rates in the range from -0.5 to +0.3 V at room temperature, and exhibits different redox processes. [ABSTRACT FROM AUTHOR]

The aim of the present study was to present the treatment observations of patients with adrenocorticotrophic hormone (ACTH)-independent macronodular adrenal hyperplasia (AIMAH) from a single medical center. A total of 23 patients with AIMAH were retrospectively reviewed according to the clinical features of the patient. Physical symptoms and biochemical evidence of Cushing's syndrome (CS) were present in all the cases. High and low dose dexamethasone failed to suppress cortisone secretion on the suppression tests and ACTH levels were low in all the cases. Bilateral enlarged adrenal glands were observed with computed tomography scans in the 23 cases, which were determined to be bilateral adrenal macronodular hyperplasia by pathological analysis. Normal blood pressure was observed in eight patients in the 2-8 years following the bilateral adrenalectomy. A total of 15 cases underwent single side adrenalectomy and their blood pressures markedly decreased three years following surgery; medical treatment was administered to 12 of the 15 patients, while three patients underwent a contralateral adrenalectomy. Nelson's syndrome was not diagnosed for any of the cases. AIMAH has unique endocrinological, radiological and pathological features, presenting as an independent etiological factor of CS. Diagnosis of AIMAH is usually derived from pathological examination and long term remission may be achieved by unilateral adrenalectomy. Contralateral adrenalectomy should be performed in cases of recurrence, when followed with periodical examination of the symptoms and the serum concentration of cortisol. [ABSTRACT FROM AUTHOR]

An impurity was detected in the roflumilast product which was supposed to be N-(3,5-dichloropyridin-4-yl)-4-difluoromethoxy-3-methoxybenzamide. To further verify the impurity structure, this compound was synthesized from 4-difluoromethoxy-3-hydroxybenzaldehyde through O-alkylation, oxidation, chlorination, and amidation reaction and characterized by H NMR, C NMR, and HPLC-MS. Comparison of the HPLC-MS spectrum of the impurity and the synthesized compound confirmed that they were the same compound. The generation of the impurity was found to be attributed to acetone and iodine in the O-alkylation system. [ABSTRACT FROM AUTHOR]

High-performance organic field-effect transistor nonvolatile memories have been achieved using sputtered C nanoparticles as the nano-floating-gate. The sputtered C nano-floating-gate is prepared with low-cost material and simple process, forming uniform and discrete charge trapping sites covered by a smooth and complete polystyrene layer. The devices show large memory window, excellent retention capability, and programming/reading/erasing/reading endurance. The sputtered C nano-floating-gate can effectively trap both holes and electrons, and it is demonstrated to be suitable for not only p-type but also n-type organic field-effect transistor nonvolatile memories. [ABSTRACT FROM AUTHOR]

A pentacene-based organic field-effect transistor nonvolatile memory, in which polystyrene covered Au nanoparticles act as the nano-floating-gate, is probed under different illumination conditions. The memory window can be greatly enlarged upon illumination depending on incident photon energy and intensity, and two light effects are proposed and discussed. The minority multiplication effect enhances the minority carrier tunneling into the nano-floating-gate, resulting in the remarkable positive V T shift. The excitation-induced injection effect is strongly photon energy dependent, and it is responsible for the significant negative V T shift. Appropriate illumination is favorable for reducing the programming/erasing voltage of organic nano-floating-gate nonvolatile memories. [ABSTRACT FROM AUTHOR]

Objectives: The objective of this study is to investigate, from a longitudinal perspective, how WHO communicated COVID-19 related information to the public through its press conferences during the first two years of the pandemic. Methods: The transcripts of 195 WHO COVID-19 press conferences held between January 22, 2020 and February 23, 2022 were collected. All transcripts were syntactically parsed to extract highly frequent noun chunks that were potential topics of the press conferences. First-order autoregression models were fit to identify "hot" and "cold" topics. In addition, sentiments and emotions expressed in the transcripts were analyzed using lexicon-based sentiment/emotion analyses. Mann-Kendall tests were performed to capture the possible trends of sentiments and emotions over time. Results: First, eleven "hot" topics were identified. These topics were pertinent to anti-pandemic measures, disease surveillance and development, and vaccine-related issues. Second, no significant trend was captured in sentiments. Last, significant downward trends were found in anticipation, surprise, anger, disgust, and fear. However, no significant trends were found in joy, trust, and sadness. Conclusions: This retrospective study provided new empirical evidence on how WHO communicated issues pertaining to COVID-19 to the general public through its press conferences. With the help of the study, members of the general public, health organizations, and other stake-holders will be able to better understand the way in which WHO has responded to various critical events during the first two years of the pandemic. [ABSTRACT FROM AUTHOR]

In this study, we used high-pressureinfrared spectroscopy to probe the local structures formed betweenthe ionic liquid [BMI][PF6] and the triblock PEO–PPO–PEOcopolymer P123. The signals for the imidazolium C–H units of[BMI][PF6] underwent anomalous frequency shifts upon dilution,induced by order-to-order transitions. Appreciable changes in therelative band intensities of the signals for the imidazolium moietiesoccurred upon compression. Upon increasing the pressure, the etherC–O–C stretching band underwent dramatic changes, witha shoulder peak appearing near 1097 cm–1with relativelyincreasing intensity. It appears that high pressures somehow stabilizethe hydrogen bonds formed between [BMI] and P123, possibly forcingthe P123 molecules to dissociate the clusters of ionic liquid throughenhanced hydrogen bonding with the imidazolium C–H units. Analogousto temperature-dependent behavior, we suggest the possibility of pressure-inducedassociation of P123 molecules through elevation of pressure. [ABSTRACT FROM AUTHOR]

Abstract: Structures located in seismically active regions may be subjected to mainshock–aftershock sequence-type ground motions, which are characterized by the presence of strong aftershock ground motions after the mainshock and separated by short intervals of time. This manuscript investigates the damage of inelastic SDOF structure with four hysteretic models and three response demand parameters. The relative intensity of the aftershock ground motion to the mainshock ground motion is defined, denoted by PGA as/PGA ms. The aftershock ground motions are scaled to have different levels of PGA as/PGA ms. The results indicate that the effect of aftershock on ductility demand is slight for PGA as/PGA ms≤0.5 and can be ignored in engineering practice. The aftershock ground motion has more significant influence on the normalized hysteretic energy and damage index than on ductility demand. The effect of aftershock ground motion with larger PGA as/PGA ms on the response demand is generally more obvious for non-degrading system than for degrading system. [Copyright &y& Elsevier]

Intrinsic Ge nanowires (NWs) with a Ge core covered by a thick Ge oxide shell are utilized to achieve nanoscale field-effect transistor nonvolatile memories, which show a large memory window and a high ON/OFF ratio with good retention. The retainable surface charge trapping is considered to be responsible for the memory effect, and the Ge oxide shell plays a key role as the insulating tunneling dielectric which must be thick enough to prevent stored surface charges from leaking out. Annealing the device in air is demonstrated to be a simple and effective way to attain thick Ge oxide on the Ge NW surface, and the Ge-NW-based memory corresponding to thick Ge oxide exhibits a much better retention capability compared with the case of thin Ge oxide. [ABSTRACT FROM AUTHOR]

Highlights: [•] The near-fault effect on constant damage inelastic displacement ratios CDI is studied. [•] Near-fault ground motion can significantly increase the CDI in medium period region. [•] The period normalization can clearly reduce the dispersion of CDI . [•] A predictive model is proposed based on the statistical results. [Copyright &y& Elsevier]

Andrographolide is a major bioactive labdane diterpenoid isolated from Andrographis paniculata and has protective effects against cigarette smoke (CS)-induced lung injury. This study was done to determine whether such protective effects were mediated through modulation of microRNA (miR)-218 expression. Therefore, we exposed human alveolar epithelial A549 cells to cigarette smoke extract (CSE) with or without andrographolide pretreatment and measured the level of glutathione, nuclear factor-kappaB (NF-κB) activation, proinflammatory cytokine production, and miR-218 expression. We found that andrographolide pretreatment significantly restored the glutathione level in CSE-exposed A549 cells, coupled with reduced inhibitor κB (IκB)-α phosphorylation and p65 nuclear translocation and interleukin (IL)-8 and IL-6 secretion. The miR-218 expression was significantly upregulated by andrographolide pretreatment. To determine the biological role of miR-218, we overexpressed and downregulated its expression using miR-218 mimic and anti-miR-218 inhibitor, respectively. We observed that miR-218 overexpression led to a marked reduction in IκB-α phosphorylation, p65 nuclear accumulation, and NF-κB-dependent transcriptional activity in CSE-treated A549 cells. In contrast, miR-218 silencing enhanced IκB-α phosphorylation and p65 nuclear accumulation in cells with andrographolide pretreatment and reversed andrographolide-mediated reduction of IL-6 and IL-8 production. In addition, depletion of miR-218 significantly reversed the upregulation of glutathione levels in A549 cells by andrographolide. Taken together, our results demonstrate that andrographolide mitigates CSE-induced inflammatory response in A549 cells, largely through inhibition of NF-κB activation via upregulation of miR-218, and thus has preventive benefits in CS-induced inflammatory lung diseases. [ABSTRACT FROM AUTHOR]

Highlights: [•] Pd-nanoparticle–graphene hybrid is simply prepared by room-temperature ionic liquid assisted sputtering method. [•] The supported Pd nanoparticles have high loading density and uniformly small sizes of 1–2nm. [•] The hybrid is in situ characterized by the surface-sensitive ambient pressure X-ray photoelectron spectroscopy. [•] The Pd-nanoparticle–graphene hybrid shows high catalytic activity for CO oxidation. [Copyright &y& Elsevier]

Abstract: This paper summarizes the comprehensive statistical results of constant damage inelastic displacement ratios which allow the evaluation of maximum inelastic displacement demand for structures with constant damage performance. The inelastic displacement ratios are calculated with modified Park-Ang damage index and inelastic single-degree-of-freedom systems subjected to 573 ground motions. The influences of period of vibration, levels of damage, site conditions, earthquake magnitude, rupture distance, post-yield stiffness, stiffness degradation, strength deterioration, parameter β and ultimate ductility factor μ u in damage index model are evaluated and discussed statistically. It is found that the effect of site conditions is not very significant. Specifically, coefficients of variation are approximately period-independent and site-independent. The degrading systems with short period of vibration would experience larger inelastic displacement than non-degrading systems. The effects of parameter β and ultimate ductility factor μ u are moderate in short period region. A simplified expression is proposed for the application of constant damage inelastic displacement ratios. [Copyright &y& Elsevier]

Pentacene-based organic field-effect transistor nonvolatile memories employing nano-floating-gate show high performance in vacuum, typically with field-effect mobility of 0.6 cm2/Vs, memory window of 45 V, reading ON/OFF ratio over 106, and excellent retention ability and programming/erasing endurance. The memory performance is unstable in air, which is demonstrated to result mainly from the device operation instability in O2. The O2-induced acceptor-like trap states reduce the electron supply in pentacene during programming, limiting the electron trapping into the nano-floating-gate and thus suppressing the positive threshold voltage shift. The corresponding hole trapping during erasing is not effectively influenced by the ambient gas effects. [ABSTRACT FROM AUTHOR]

Abstract: Strong aftershocks have the potential to increase the damage state of the structures due to the damage accumulation. This paper investigates the damage spectra for the mainshock–aftershock sequence-type ground motions with Park–Ang damage index. A method of simulating the mainshock–aftershock sequence-type ground motions is proposed based on the modified form of Bath''s law and NGA ground motion prediction equation. The damage spectra are computed using the recorded and simulated sequence-type ground motions, and the effects of period of vibration, strength reduction factor, site condition, seismic sequence, damping ratio and post-yield stiffness on damage spectra are studied statistically. The results indicate that the effect of aftershock on structural damage is significant and recorded sequence-type ground motions may underestimate the damage of long-period structures due to the incompleteness of dataset. A simplified equation is proposed to facilitate the application of damage spectra in the seismic practice for mainshock–aftershock sequence-type ground motions. [Copyright &y& Elsevier]

Low-velocity ballistic experiments were carried out to study the perforation-resistant mechanisms of warship topside composite armor system, which was simulated by composite laminates at the front and homogeneous steel plates at the back. Failure modes and energy absorbing mechanisms were investigated and the influence of the area density of front composite armors on total perforation resistance of combined targets was analyzed. Based on the experiments, an equation was obtained to predict the residual velocities in the case of low-velocity perforation of combined targets by hemispherical-nosed projectiles according to the failure modes of the targets. The results show that under low velocity perforation, combined targets mainly exhibit local damage. A few amounts of fiber at the impact side of front composite armor are sheared by the projectile. Failure modes of front composite armors are mainly fiber tensile rupture while for steel backing plates, failure modes are primarily petaloid damage. The whole energy-absorbing capability of combined targets increases with increasing the area density of front composite armors. It is shown that theoretical predictions coincide with the experimental results in terms of residual velocities. [ABSTRACT FROM AUTHOR]

Abstract: Flower initiation and development of Kalanchoe spp. were investigated in this study. The sequence of events in the differentiation process was divided into 8 stages: vegetative growth, flower initiation, bract primordium, sepal primordium, petal primordium, stamen primordium, pistil primordium, and visible floret stages. Under the short-day condition, Kalanchoe spathulata, Kalanchoe blossfeldiana ‘Tenorio’, and Kalanchoe garambiensis meristems initiated differentiation after 5, 10, and 15 days, respectively. K. spathulata, K. garambiensis, and K. blossfeldiana ‘Tenorio’ differentiated from the vegetative stage into the visible flower bud stage in 45, 50, and 55 days, respectively. The development from flower initiation to the visible flower bud stage was most rapid in K. spathulata, followed by K. garambiensis and K. blossfeldiana ‘Tenorio’. Kalanchoe gracilis differentiated from the vegetative growth stage into the visible flower bud stage in 105 days. Therefore, K. spathulata and K. garambiensis exhibited flower characteristics relatively early. The main differences in flowering between species/cultivars were initiation timing and the time for subsequent development. The sepal primordial stage was the most sensitive stage to the short-day condition during flower development in Kalanchoe spp. The minimum number of short-days needed for flowering of K. spathulata, K. garambiensis, K. blossfeldiana ‘Tenorio’, and K. gracilis were 15, 15, 25, and 56 days, respectively. Therefore, K. spathulata or K. garambiensis can be used to produce hybrids in relatively fewer short-days. [Copyright &y& Elsevier]

Abstract: We report high-performance organic field-effect transistor nonvolatile memory based on nano-floating-gate, which shows a large memory window of about 70V, high ON/OFF ratio of reading current over 105 after 1week storage, high field-effect mobility of 0.6cm2/Vs, and good programming/erasing/reading endurance. The devices incorporate Au nanoparticles and polystyrene layer on top to form the nano-floating-gate, and we demonstrate that the morphology control of the tunneling dielectric is critically significant to improve the memory performance. The optimized tunneling dielectric morphology is favorable to the efficient charge tunneling, reliable charge storage and high-quality organic film growth. [Copyright &y& Elsevier]

Abstract: We report a generic strategy to make hybrids incorporating metal nanoparticles and carbon nanosupports with large surface area, which is a one-step, universal approach totally free of additives and by-products. Utilizing this approach, we show that small Au, Ag and Pd nanoparticles of uniform size can be self-assembled on diverse carbon nanostructures such as graphene oxide, reduced graphene oxide, and multiwalled carbon nanotubes by simply sputtering metal onto room-temperature ionic liquids. The size of metal nanoparticles can be controlled by the composition of room-temperature ionic liquids, and the surface density of metal nanoparticles can be controlled by the sputtering conditions. The self-assembly is demonstrated to be driven by the interlinking interactions among the metal nanoparticles, ionic liquid cations and carbon nanostructures. [Copyright &y& Elsevier]

Abstract: Previous research has demonstrated that diabetes induces learning and memory deficits. However, the mechanism of memory impairment induced by diabetes is poorly understood. Dietary fatty acids, especially polyunsaturated fatty acids, have been shown to enhance learning and memory and prevent memory deficits in various experimental conditions. The present study investigated the effects of fish oil supplementation on the neuron apoptosis in the hippocampus of streptozotocin (STZ)-induced diabetes rats. The effects of diabetes and fish oil treatment on the spatial learning and memory were also evaluated using the Morris Water Maze. Diabetes impaired spatial learning and memory of rats. Diabetes increased the expression of Bax and caspase-3, which led the apoptosis of the CA1 pyramidal neurons, and further contributed to the deficits in learning and memory processing. Fish oil dietary supplementation in diabetic rats conducts neuron-protective function through an anti-apoptotic pathway and significantly improves the ability of learning and memory. These results partially explain the mechanism of the effect of diabetes and fish oil treatment on learning and memory, supporting a potential role for fish oil as an adjuvant therapy for the prevention and treatment of diabetic complications. [Copyright &y& Elsevier]

This paper evaluates accuracies and applicabilities of frame elements constructed by displacement-based (DB), force-based (FB) and plastic hinge (PH) methods for structural non-linear static analysis. The theoretical bases of the three frame elements are compared and the global response (nodal level) and local response (sectional level) of the three frame elements are evaluated. The results lead to the conclusions that more DB elements than FB elements need to be employed to obtain accurate post-yielding global responses in the cases of sections undergoing hardening or zero post stiffness. Both DB and FB elements fail to provide consistent and rational evaluation of the post-yielding global responses in the case of sections undergoing softening. The post-yielding global responses presented by the PH element are strongly influenced by the preset hinge length. The three frame elements present consistent local response results but different maximum responses in most cases. The preferred numbers of integration points to be used in DB and FB elements are also advised from the points of view of both consistency and stability. [ABSTRACT FROM AUTHOR]

Low-frequency and high-power ultrasound (40 kHz, 1,500 W) was tested for its effects on the characteristics of intramuscular heat-insoluble collagen and meat quality and textural properties of beef semitendinosus muscle. Meat steaks (2.5 × 5.0 × 5.0 cm, 100 ± 5 g) were sonicated for 10, 20, 30, 40, 50, and 60 min, respectively. Characteristics changes of collagen and meat quality and texture were estimated. The results indicated that ultrasound treatment had no significant ( P > 0.05) effects on L* (lightness) and a* (redness) values but decreased b* (yellowness) value significantly when sonicated for 30 min (minimum 6.98). Ultrasound treatment significantly ( P < 0.01) reduced the muscle fiber diameter and filtering residues but had no significant effects on the content of heat-insoluble collagen. Significant differences ( P < 0.05) in β-galactosidase and β-glucuronidase activity were found between ultrasound treated for 10 min (reached the minimum were 5.2 × 10 and 1.6 × 10 umol∙ml∙min, respectively) and control samples. Thermal characteristics analysis of collagen suggested that ultrasound treatment weaken the average stability of collagen. After ultrasound treatment, collagenous fibers were disordered and staggered significantly; fiber arrangement became loose; and the denaturing, granulation, and aggregation of collagen fiber appeared in the extracellular space. Those changes on collagen characteristics had significant effects on meat textural properties. The results suggested that low-frequency and high-power sonication had a significant effect on collagen characters and meat textural properties. [ABSTRACT FROM AUTHOR]

Abstract: Hepatic oval cells (HOC) are considered to be the stem cells of the liver and have been linked to the development of hepatic malignancies. Studies have demonstrated that chronic hepatitis B virus (HBV) infection and dietary aflatoxin B1 (AFB1) exposure are among the most important risk factors for the development of hepatocellular carcinoma (HCC). However, little research has been done to evaluate the role of oval cells in these two environmental factors on hepatocarcinogenesis. In this study, partial transformation of rat HOC (LE/6) were accomplished by transfected HBV x gene (HBx), and then transfected cells were implanted both intra-hepatically and subcutaneously into nude mice treated with AFB1 in vivo. We found the oval cells produced tumors (4/24 of the animals) in liver following transfection with HBx gene and treatment with AFB1. These intrahepatic tumors included HCC cells (immunopositive for HepParl, ALB, CK8 and AFP) and mesenchymal cells (immunopositive for Vimentin and SMA). Whereas mesenchymal tumors were observed at the subcutaneous tissue with a similar rate in all controls treated with cell lines (10/24 in HBx-oval cells/AFB1 group, 8/20 in HBx-oval cells/non-AFB1 group, 10/20 in non-HBx/AFB1 group; 9/20 in non-HBx/non-AFB1 group). Conversely, none of the controls developed intrahepatic tumors. These results provide an evidence that oval cells have the capacity to generate HCC through the combined effects of the HBx and AFB1 in the liver microenvironment. [Copyright &y& Elsevier]