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The sol-gel process has been applied to cotton fabrics to cover the fibers with a silica-based film, which can improve their thermal oxidation and combustion behaviors. Silica sol, silane coupling agent 3-glycidoxypropyltrimethoxysilane (KH560) and flame retardant zinc borate (ZB) are used together to prepare SiO2-KH560-ZB hybrid sol, which is then finished on the surface of cotton fabric through impregnation and baking. Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), limiting oxygen index analysis (LOI) and microscale combustion calorimetry (MCC) are used to characterize functional groups, thermal stability and flammability properties of finished fabrics. Surface morphology of sol modified cotton fabrics are analyzed by scanning electron microscopy (SEM) and energy dispersive X-Ray spectroscopy (EDX). Results show the sols are successfully converted into gel coatings onto cotton fabrics, and continuous smoldering phenomenon of resulted fabrics disappears. ΔLOI/Δm of SiO2-KH560-ZB coated cotton fabric reaches the highest of 0.37%/g, char residue rate is as high as 28.43% and the peak heat release rate (PHRR) is reduced by 26.9% (83.7 W/g). KH560 has a significant coupling effect on combining components in the sol system and increases compatibility between sols and cotton fabrics. ZB (cooling, separation, dilution and suppression), silica sol (physical barrier) and KH560 show excellent synergistic effects in enhancing overall flame retardancy.

Recent studies suggested that the interactions between particles can induce aggregative nucleation and growth processes beyond those predicted by the traditional LaMer model of nanoparticle formation, but their nucleation and growth processes are still unclear. Here, we report a simple way to control the interaction between nanoparticles by manipulating the oleylamine (OAm) adsorbed on the surface of the nanoparticles. The size distributions of Ag nanoparticles produced at different reaction pressures were monitored as evidence for aggregative growth. From these kinetic data, the aggregative nucleation rate (Γ) of primary Ag nanoparticles under a 0.01 MPa was demonstrated to be faster than that under atmospheric pressure. This leads to a higher uniformity of Ag nanoparticles in a shorter time (10 min) than that achievable with previous methods. Furthermore, Ag nanoparticles supported on TiO2 exhibited a remarkable performance in the catalytic reduction of 4-nitrophenol (4-NP). After 4 min, 4-NP was completely reduced into 4-aminophenol (4-AP).

Summary Toward the preparation of industrial metal oxide catalysts, sacrificial organic templates, excessive solvents, complex impregnation, and drying steps are generally required. Here, we report a versatile rule for the simple synthesis of highly porous metal oxides with well-dispersed noble metal species. Porous metal oxides (Co3O4, FexOy, and Cr2O3) are obtained with some surface areas (e.g., Cr2O3: 224 m2·g−1) beyond the record value. Surprisingly, small noble metal nanoparticles (e.g., Pd: 3.1 and Pt: 3.2 nm) could be incorporated by this solid-state process simultaneously. Corresponding Rh-Co3O4, Pd-FexOy, and Pt-Cr2O3 exhibit excellent performance: CH4 combustion (T90 = ∼360°C and thermal stability: >100 h at 680°C), hydrogenation of nitrobenzene and derivatives (turnover number [TON] = 2.49 × 104, 300 mmol per run), and reversed water gas shift (RWGS) reaction (44% CO2 conversion with ∼98% CO selectivity and thermal stability: >100 h at 500°C), respectively. Therefore, current principle via a NaCl-based solid solution could provide a solid-state, fast, and efficient route for processing metal oxide catalysts.

Multi-walled carbon nanotube (MWCNT)/dextran/nano-gold composite was prepared by chemical solution reaction. The average diameter of gold nanoparticles was around 15 nm. MWCNT/dextran/nano-gold composites were uniformly dispersed in aqueous solution as electrode materials. MWCNT/dextran/nano-gold composites exhibited excellent electrochemical property in [Fe(CN)6]3– /4– solution. Experimental results showed that the MWCNT/dextran/nano-gold composites with 50% MWCNTs presented obvious redox peak and low impedance and had good electrochemical response to Cu2+. The redox peak currents were linear while the concentration of copper ions ranged from 1× 10–2 to 1 × 10–4 M. The relationship between oxidation peak currents I (A) and Cu2+ concentration C (M) was: ipk (A) = 2.6207 × 10–6 + 43.91572 × 10–4 × C (M), and the limit of determination (LOD) of Cu2+ was 0.63 × 10–6 M, and linear coefficient was 0.9923.

The sintering of Supported Transition Metal Catalysts (STMCs) is a core issue during high temperature catalysis. Perovskite oxides as host matrix for STMCs are proven to be sintering-resistance, leading to a family of self-regenerative materials. However, none other design principles for self-regenerative catalysts were put forward since 2002, which cannot satisfy diverse catalytic processes. Herein, inspired by the principle of high entropy-stabilized structure, a concept whether entropy driving force could promote the self-regeneration process is proposed. To verify it, a high entropy cubic Zr0.5(NiFeCuMnCo)0.5Ox is constructed as a host model, and interestingly in situ reversible exsolution-dissolution of supported metallic species are observed in multi redox cycles. Notably, in situ exsolved transition metals from high entropy Zr0.5(NiFeCuMnCo)0.5Ox support, whose entropic contribution (TΔSconfig = T⋆12.7 J mol−1 K−1) is predominant in ∆G, affording ultrahigh thermal stability in long-term CO2 hydrogenation (400 °C, >500 h). Current theory may inspire more STWCs with excellent sintering-resistance performance., Sintering of supported transition metal catalysts is problematic for high-temperature catalysis. Here the authors report entropy-driven, self-regeneration of high entropy oxide nanoparticles, promoting better stability and in situ reversible exsolution-dissolution process in multi-redox cycles.

Clostridium tyrobutyricum (C. tyrobutyricum) is a fermentation strain used to produce butyric acid. A promising new biofuel, n-butanol, can be produced by catalysis of butyrate, which can be obtained through microbial fermentation. Butyric acid has various uses in food additives and flavor agents, antiseptic substances, drug formulations, and fragrances. Its use as a food flavoring has been approved by the European Union, and it has therefore been listed on the EU Lists of Flavorings. As butyric acid fermentation is a cost-efficient process, butyric acid is an attractive feedstock for various biofuels and food commercialization products. 12C6+ irradiation has advantages over conventional mutation methods for fermentation production due to its dosage conformity and excellent biological availability. Nevertheless, the effects of these heavy-ion irradiations on the specific productiveness of C. tyrobutyricum are still uncertain. We developed non-structured mathematical models to represent the heavy-ion irradiation of C. tyrobutyricum in biofermentation reactors. The kinetic models reflect various fermentation features of the mutants, including the mutant strain growth model, butyric acid formation model, and medium consumption model. The models were constructed based on the Markov chain Monte Carlo model and logistic regression. Models were verified using experimental data in response to different initial glucose concentrations (0–180 g/L). The parameters of fixed proposals are applied in the various fermentation stages. Predictions of these models were in accordance well with the results of fermentation assays. The maximum butyric acid production was 56.3 g/L. Our study provides reliable information for increasing butyric acid production and for evaluating the feasibility of using mutant strains of C. tyrobutyricum at the pre-development phase.

Mesoporous iron oxides have shown excellent performance in many research areas such as catalysts, biosensors, enzyme immobilization, heavy metal adsorption, and drug delivery. The state-of-the-art synthesis methods are mostly wet chemistry processes. This paper reports a solvent-free approach for the rapid synthesis of mesoporous Fe 3 O 4 (specific surface area up to 170 m 2 /g) and Au@Fe 3 O 4 (highly dispersed Au nanoparticles, average particle size: ∼4 nm). With different amounts of added template agent, cetyltrimethylammonium bromide (CTAB), the pore structure could easily be adjusted. More importantly, the mesoporous Fe 3 O 4 exhibited good catalytic activity in carbon monoxide (CO) oxidation, outperforming commercially purchased Fe 3 O 4 with 100% CO conversion at around 274 °C vs. 490 °C for the commercial product.

Lumbar disc herniation is a common cause of radicular pain, but the mechanism remains ambiguous and the treatment stays unsatisfied. Many studies revealed a traditional Chinese medicine puerarin may moderate chronic pain from diabetes and nerve injury. Thus far, the role and mechanism of puerarin in radicular pain is still unknown. In this study, by using a rat model of lumbar disc herniation, which was induced by autologous nucleus pulposus (NP) implantation, the analgesic effect of puerarin on radicular pain was tested. Puerarin was delivered intraperitoneally form 1 h before surgery, and once daily for 7 days. The results demonstrated that NP implantation induced long-lasting pain, characterized by decrease of paw withdrawal threshold (PWT) and paw withdrawal latency (PWL) in ipsilateral hindpaws, as long as day 20 after surgery. Spinal phosphorylated extracellular signal-regulated kinase (p-ERK) was up-regulated from day 5 to day 20 after surgery in ipsilateral but not contralateral side, and p-ERK was mainly co-localized with microglia. Puerarin decreased p-ERK expression from day 7 to day 20 after surgery. Puerarin or ERK inhibitor PD98059 alleviated pain behaviors, decreased expression of microglia marker ionized calcium-binding adaptor molecule 1 (Iba-1) in rats with NP implantation. The results suggested puerarin may alleviate radicular pain by inhibiting ERK-dependent or accompanied spinal microglia activation.

Releasing saponins to aqueous phase from Dioscorea zingiberensis C. H. Wright tubers is an effective way to decrease water pollution in diosgenin industry. Aqueous saponins (AS) are unstable during storage and could be hydrolyzed under certain conditions. To preserve the maximum AS content, different storage methods were evaluated, and it was found that storage at −20 °C and storage after 80 °C drying could well maintain AS content stability. AS model solution system was then constructed and utilized to simulate storage process. Adding sodium dodecyl sulphate and boiling can both effectively ensure the stability of AS content, while acid shock deferred the decrease of AS content. AS content decreased after sequential effects of endogenous enzymes and microbial community from tubers in different phase during storage. Myroides, Enterococcus, Alcaligenes and Stenotrophomonas were enriched as storage proceeded. It was also concluded that multiple glycosidase and surfactants secreted by selectively enriched microbial community decreased AS content stability at late stage of storage. This study also provides a guideline for preventing the loss of glycoside bioactive constituents in other industrial crops during storage.

Berberine, a natural isoquinoline alkaloid isolated from the berberis species, has a wide array of biological properties such as anti-inflammatory, antibacterial, antifungal, and antihelminthic effects. We evaluated the antiviral effect of berberine against influenza A/FM1/1/47 (H1N1) in vivo and in vitro. The results showed that berberine strongly suppressed viral replication in A549 cells and in mouse lungs. Meanwhile, berberine relieved pulmonary inflammation and reduced necrosis, inflammatory cell infiltration, and pulmonary edema induced by viral infection in mice when compared with vehicle-treated mice. Berberine suppressed the viral infection-induced up-regulation of TLR7 signaling pathway, such as TLR7, MyD88, and NF-κB (p65), at both the mRNA and protein levels. Furthermore, berberine significantly inhibited the viral infection-induced increase in Th1/Th2 and Th17/Treg ratios as well as the production of inflammatory cytokines. Our data provide new insight into the potential of berberine as a therapeutic agent for viral infection via its antiviral activity.

The aim of this study was to well understand the impacts of innovative drying techniques (radio frequency drying and microwave drying) and traditional drying techniques (vacuum drying, freezing drying, and hot air drying) on the structural characteristics and bioactivities of polysaccharides from dandelion leaves (DLPs). Five different DLPs were obtained from dandelion leaves dried by abovementioned drying techniques. Results showed that the structural characteristics and bioactivities of DLPs varied with different drying techniques. The molecular weights, apparent viscosities, molar ratios of constituent monosaccharide, contents of uronic acids, and contents of bonded polyphenolics in DLPs obtained by different drying techniques had noticeable variations, while the types of constituent monosaccharides and the major glycosidic linkages in DLPs were similar. In addition, results showed that DLPs, especially DLP-RF obtained by the radio frequency drying, exhibited remarkable antioxidant activities (ABTS, DPPH, and NO radical scavenging activities), excellent in vitro antiglycation activity, and obvious in vitro inhibitory activity on α-glucosidase. Results from this study suggest that the radio frequency drying can be used as a potential drying technique before extracting DLPs for applications in the functional food and medicine industries.

By thermogravimetric (TG) experiments under 5 oxygen concentrations of 21.0, 40.0, 50.0, 60.0, 80.0% and 5 heating rates of 20.0, 30.0, 40.0, 50.0, 60.0 ℃/min, the combustion characteristics of jet coal and influences of oxygen concentrations and heating rates on them were investigated. Results show that the pyrolysis processes of jet coals consist of 3 segments of water evaporation, structure oxidation and mass-gaining, self-ignition and induced combustion and carbonization that lie in temperature ranges of 65.0~150.0 ℃, 150.0~290.0 ℃ and 290.0~650.0 ℃, respectively. Huainan jet coal samples burn more easily as universal ignition index increases. At constant heating rate, self-ignition temperature tends to decrease by 10.1~19.4 % with increasing oxygen concentration from 21.0 % to 80.0 %. However, the variation trend of oxidation process includes a slight rise when variation trend begins to fall. At constant oxygen concentration, the self-ignition temperature transformes into high temperature direction and lead to thermal lag effect. Values of Coal-oxidation time at various oxygen concentration levels decreased by 63.1~65.8 % at heating rates from 20.0 to 60.0 ℃/min. Accordingly, the coal-oxidation process is accelerated. A new index (R S ) named coal-oxidation difficulty level index to evaluate the lag effect of coal-oxidation process was proposed. Fitting results of three dimensionless parameters confirmed that the risk of spontaneous combustion determined by the coal-oxidation process still remains growing up although self-ignition temperature produces thermal lags with increasing heating rates.

By using sol-gel process, hybrid sols can be prepared and three dimensional nanoscale or nano-micro networks can be designed and formed onto bulk materials of diverse substrates (such as fabric and wood). Series of pure, composite and hybrid sols like SiO2, SiO2-KH560, SiO2-KH560-MA (Melamine), SiO2-KH560-BB (Boric Acid and Borax) and SiO2-KH560-TPP (Triphenyl Phosphate) including both nano-sols and traditional flame retardant components were prepared and used to finish cotton, polyester and polyester-cotton fabrics, particle size distributions and pH values of as-prepared sols were inspected. Limiting Oxygen Index (LOI), Thermogravimetry Analysis (TGA) and Fourier Transform Infrared Spectroscopy (FTIR) experiments were conducted to determine flame retardancy, characterize pyrolysis properties and identify microstructural functional groups on the surfaces of sols-finished fabrics. Effectiveness, synergistic effects and function mechanisms of organically modified hybrid sols and flame retardants were explored. Results show that LOI values are all improved after modifications of cotton, polyester and polyester-cotton fabric, coverage of main pyrolysis stage have been extended to various degrees, and amounts of residual char increase exponentially. The flame retardant effects of cotton and polyester-cotton fabrics treated with SiO2-KH560-BB is most obvious. It shows that the flame retardant hybrid sols affect the pyrolysis courses and heat resistance capacities of fabrics have been improved. It is speculated the sols form coatings on surface of fabrics and inhibit further oxidation, decomposition, and melt dripping, prolong the main pyrolysis process, prevent the fabric further oxidation and decomposition, increase the char yield, improve the thermal stability of polyester fabric. For A3, a broad peak between 650~750cm-1 is seen, indicating that a large number of OH groups exist, and absorption peaks at 1295 cm-1 reveals the presence of Si-C-O groups. The OH groups, boric acid and borax can both strengthen dehydration and char formation capacities by developing thin films surrounding fibers. Superb synergistic effect happens.

Zinc oxide is a key material in catalysis. Designing of ZnO crystal aggregates with the surface defect has received significant attention. Herein, we synthesized ZnO aggregates with tiny primary nanoparticles through a mechanochemistry-assisted salt-templating (potassium chloride) method. Interestingly, this KCl-templating strategy could lead to significant increase in specific surface area (SSA) of ZnO (up to 91 m2/g), whereas commercial ZnO-COM has a SSA of 5 m2/g. Meanwhile, this strategy via ZnCl2-KCl solid solution has also created a number of oxygen vacancies into ZnO aggregates. With these attractive features, as-made Pd-ZnO catalyst showed outstanding performance in methanol steam reforming, especially at low temperature (20 % Conversion and 95 % CO2 Selectivity at 150 °C). Current strategy provides a gateway for the rational design of ZnO-based catalytic materials.

Two new compounds based on Cd(II) ion as metal nodes, that is, [Cd (pam) (3-bpmh) (DMF)]n (1) and [Cd2(Hbci)2 (3-bpmh)2]n·nH2O (2) (3-bpmh is N,N-bis-pyridin-3-ylmethylene-hydrazine, H3bci ​= ​bis(2-carboxyethyl)isocyanurate, and H2pam ​= ​pamoic acid), were successfully prepared via a dual-ligand strategy under solvothermal conditions. Furthermore, the luminescent performances and thermal stabilities of the prepared compounds were explored. During myocardial infarction, there were characteristic changes of the patients' electrocardiograms. For the treatment of ischemic myocardial infarction, the adenosine 5′-monophosphate-activated protein kinase inflammatory signaling pathway was determined through applying real-time reverse transcription-polymerase chain reaction after conducting the indicated treatment. Next, the enzyme-linked immunosorbent assay was implemented, and the levels of inflammatory cytokines during ischemic myocardial infarction were determined.

The stabilization of surfactant-assisted synthesized colloidal noble metal nanoparticles (NPs, such as Au NPs) on solids is a promising strategy for preparing supported nanocatalysts for heterogeneous catalysis because of their uniform particle sizes, controllable shapes, and tunable compositions. However, surfactant removal to obtain clean surfaces for catalysis through traditional approaches (such as solvent extraction and thermal decomposition) can easily induce the sintering of NPs, greatly hampering their use in synthesis of novel catalysts. Such unwanted surfactants have now been utilized to stabilize NPs on solids by a simple yet efficient thermal annealing strategy. After being annealed in N2 flow, the surface-bound surfactants are carbonized in situ as sacrificial architectures that form a conformal coating on NPs and assist in creating an enhanced metal-support interaction between NPs and substrate, thus slowing down the Ostwald ripening process during post-oxidative calcination to remove surface covers.

The photoisomerization kinetics of IR125 and HDITCP in ionic liquids with different cation alkyl chain lengths were investigated by measuring their fluorescence lifetimes and quantum yields using steady-state absorption and fluorescence spectroscopies, and time-correlated single-photon counting experiments. It was found that the photoisomerization rate constants for IR125 and HDITCP in all the selected ionic liquids were almost identical and did not change with increasing ionic liquid viscosity. A comparison of the photoisomerization rate constants of IR125 and HDITCP in isoviscous aqueous glycerol solutions with those in ionic liquids showed that the photoisomerization energy barriers of IR125 and HDITCP in ionic liquids were about 2 kJ∙mol-1 higher than those in the isoviscous aqueous glycerol solutions, indicating that specific interactions between IR125 or HDITCP and the ionic liquid restrain their respective photoisomerization processes in highly viscous ionic liquids.

The effects of tea polysaccharides (TPS) and polyphenols (TPP) on the growth inhibition of hepatoma H22 cells in mice including the roles of them in immune stimulation were investigated. The results showed that TPS and TPP both significantly inhibited the growth of H22 transplantable tumor in mice without statistical difference, both remarkably decreased the spleen index and increased the thymus index compared with that of model group (p<0.05). In addition, TPS and TPP significantly improved the splenocyte proliferation induced by ConA or LPS, and notably enhanced the macrophage phagocytosis towards neutral red. The comparison showed the effect of TPS on immune stimulation was superior to that of TPP to some extent.

Based on the latest national carbon dioxide emissions data released from the International Energy Agency (IEA), the carbon dioxide emissions trends of BRICS were analyzed in three aspects: the total carbon dioxide emissions, the emission intensity calculated using purchasing power parties (PPP) and per capita carbon dioxide emissions. The results show that the total carbon dioxide emissions among BRICS presented an increasing trend in different extent. On the other hand, the emission intensity calculated using PPP of BRICS showed a decreasing trend. The per capita carbon dioxide emissions of BRICS also presented an increasing trend in different extent. The Russian Federation and South Africa’s per capita carbon dioxide emissions were higher than the World’s average level, whilst those of India, Brazil and China were lower than the World’s average level, which is far less than the level of the OECD countries.

Highly-ordered TiO2 nanotube arrays (TNTs) were prepared by anodisation in ethylene electrolytes containing 0.2–0.7 wt% NH4F. The dimension, chemical composition and optical characterisation of prepared TNTs were determined by the field-emission scanning electron microscopy, X-ray photoelectron spectroscopy and photoluminescence spectroscopy, respectively. Both the length and inner diameter of the prepared TNTs were increased with increasing NH4F concentration of electrolyte because of the faster electrochemical dissolution rate of TiO2. However, dimension of TNTs approached stable lengths and inner diameters as the NH4F concentration was higher than 0.3 wt%. The presence of Ti3+ state was observed for TNTs prepared with increasing NH4F concentration because of the charge compensation of the substitution of fluoride ions for oxygen ions. TNTs prepared in the electrolytes containing higher NH4F concentrations exhibited superior performance on the photocatalytic decomposition of Acid Red 4 possibly because more fluorides incorporated with TNTs to inhibit the recombination of electron–hole pairs.

The phase-pure LiFePO4/C cathode materials have been successfully fabricated by precursor containing Fe2O3 coated with polyaniline through carbothermal reduction method. The polyaniline coating at Fe2O3 could restrict the growth of crystal and subsequently become electric carbon at higher synthesis temperature. Compared with conventional carbothermal reduction method, the sample showed a better capacity and less than 3% capacity fading after 30 cycles at various charge and discharge rate.

Alpha-lipoic acid (ALA) is often used as a dietary supplement to prevent and treat chronic diseases associated with excessive oxidative stress. The aim of this study was to investigate the mechanisms of the antiplatelet activity of ALA. ALA significantly inhibited collagen-induced platelet aggregation, thromboxane B(2) (TXB(2)) formation, Ca(2+) mobilization, and protein kinase Calpha (PKCalpha) activation, but ALA itself increased cyclic AMP formation in rabbit washed platelets. However, the effects of ALA on the above platelet responses were markedly reversed by the addition of 2'5'-ddAdo, an adenylate cyclase inhibitor. Additionally, increased reactive oxygen species (ROS) formation and cyclooxygenase-1 activity stimulated by arachidonic acid were inhibited by ALA. In conclusion, we demonstrated that ALA possesses an antiplatelet activity, which may be associated with an elevation of cyclic AMP formation, involving subsequent inhibition of TXA(2), Ca(2+) mobilization, and PKCalpha-mediated pathways. Moreover, inhibition of ROS formation and increase of platelet membrane fluidity may also involve its actions.

Partial liquid ventilation with various types of perfluorocarbon (PFC) has been shown to be beneficial in treating acute lung injury, a clinical outcome that may involve the anti-inflammatory activity of PFC. FC-77 is a type of PFC with relatively higher vapor pressure and evaporative loss than other PFCs during partial liquid ventilation. Overproduction of nitric oxide (NO) by inducible nitric oxide synthase (iNOS) has been proposed to play a crucial role in the pathogenesis of inflammatory diseases. However, whether the iNOS/NO pathway is affected by FC-77 is unknown. Thus, the aim of this study was to investigate whether FC-77 inhibits iNOS expression and NO production in lipopolysaccharide (LPS)–treated RAW 264.7 macrophages. We found that treatment with FC-77 significantly attenuated LPS-induced iNOS expression/activity and production of NO and reactive oxygen species (ROS). FC-77 also attenuated LPS-induced pro-inflammatory cytokine formation, but enhanced interleukin-10 production. Furthermore, the LPS-induced degradation of cytosolic IκB-α and activation of nuclear transcription factor-κB (NF-κB) were also inhibited by FC-77. In conclusion, the present study is the first to demonstrate that FC-77 decreases LPS-induced NO production in macrophages, which may be associated with the suppression of pro-inflammatory cytokines, and ROS production, as well as NF-κB activation. These results also provide a novel explanation for its anti-inflammatory activity. Keywords:: perfluorocarbon, nitric oxide, lipopolysaccharide, cytokine, macrophage

Exchange coupling and magnetization reversal mechanism in two series of CoxNi1−x/CoO (30 nm) (x=0.2 and 0.4) bilayers are studied by vector magnetometer. Two components of magnetization are measured parallel and perpendicular to the applied field. At low temperatures, coercivity Hc ∝ (tFM)−nn = 1.5 and 1.38 for x = 0.2 and 0.4, respectively, in agreement with the random field model. At room temperature, the coercivity is nearly proportional to the inverse FM layer thickness. In addition to the exchange field and the coercivity, the characteristic of the magnetization reversal mechanism was found to change with temperature. At temperatures below 180 K, magnetization reversal process along the unidirectional axis is accompanied only by nucleation and pinning of domain wall while magnetization rotation is also involved at high temperatures.

This study aimed to investigate the mechanisms involved in Microcystis aeruginosa (M. aeruginosa) compensatory growth after moderate high-temperature stress. In the experiment, M. aeruginosa were cultured for 3, 6, and 12 d at 35°C before being transferred to normal conditions (25°C), and then cultured for 30 days for recovery. The algae that were cultured constantly at 25°C were set as control. The results showed that the growth of M. aeruginosa was inhibited significantly by the moderate high-temperature stress. During the recovery phase, the M. aeruginosa cultured at 35°C for 3, 6, and 12 days exhibited under-compensation, over-compensation, and equal-compensation, respectively. To cope with moderate high-temperature stress, M. aeruginosa implement various mechanisms, including increasing antioxidant enzyme activities and chlorophyll a content; adjusting compatible solutes (soluble protein and sugar). The M. aeruginosa cultured at 35°C for 6 days has higher antioxidant enzyme activities, relatively low malondialdehyde content, and higher soluble sugar content during the recovery phase; therefore, M. aeruginosa cultured at 35°C for 6 days exhibited over-compensation growth. Grey correlation analysis revealed that the increase of chlorophyll a, soluble sugar, and superoxide dismutase activity play key roles in the compensatory growth of M. aeruginosa.

C-phycocyanin (cpc), a biliprotein isolated fromSpirulina platensis, has been reported to exert many therapeutic and nutritional values. In the present study, we examined whether cpc has an antiplatelet activityin vitroand further investigated the possible anti-aggregatory mechanisms involved. Our results showed that preincubation of cpc (1–50μg/ml) with rabbit washed platelets dose-dependently inhibited the platelet aggregation induced by collagen (10μg/ml) or arachidonic acid (100μm), with an ic50of about 10μg/ml. Furthermore, the thromboxane B2formation caused by collagen or arachidonic acid was significantly inhibited by cpc due to suppression of cyclooxygenase and thromboxane synthase activity. Similarly, the rise of platelet intracellular calcium level stimulated by arachidonic acid and collagen-induced platelet membrane surface glycoprotein IIb/IIIa expression were also attenuated by cpc. In addition, cpc itself significantly increased the platelet membrane fluidity and the cyclic AMP level through inhibiting cyclic AMP phosphodiesterase activity. These findings strongly demonstrate that cpc is an inhibitor of platelet aggregation, which may be associated with mechanisms including inhibition of thromboxane A2formation, intracellular calcium mobilization and platelet surface glycoprotein IIb/IIIa expression accompanied by increasing cyclic AMP formation and platelet membrane fluidity.

This study tested whether FC-77, a perfluorochemical, inhibits inflammatory responses in lipopolysaccharide (LPS) stimulated RAW 264.7 macrophages. The possible anti-inflammatory mechanisms involved were also investigated.RAW 264.7 macrophages were simultaneously incubated with pure FC-77 at final volume of 10% or 30% (v/v) and LPS (1 microg/ml) for 12 or 24 h on a mechanical shaker. In some tests FC-77 was added after cells stimulated by LPS for 12 h. Then the levels of prostaglandin E2(PGE2), tumor necrosis factor alpha (TNF-alpha), and interleukins (IL)-1beta, -6), and -10 were measured in medium. Alterations in cyclooxygenase (COX) 2 expression and nuclear transcription factor (NF) kappaB activation in cells were also evaluated.Pre- or posttreatment with FC-77 dose-dependently reduced the LPS-induced TNF-alpha, IL-1beta, and IL-6 formation and enhanced IL-10 production compared to LPS-stimulated alone cells. FC-77 also attenuated the LPS-induced PGE2 formation accompanied by suppressing COX-2 expression, the degradation of cytosolic inhibitor of kappaB-alpha and NF-kappaB activation.FC-77 inhibits inflammatory responses in LPS-stimulated macrophages by a mechanism that involves the attenuation of NF-kappaB dependent induction of COX-2/PGE2 pathway and the pro- /anti-inflammatory cytokine ratio.

In this paper, a novel output-power controllable erbium-doped fibre laser, based on a strain-applied high-birefringence fibre loop mirror (HBFLM), was proposed and demonstrated. The reflectivity of HBFLM could be changed from about 0.8% to 100% because the fibre length and birefringence of the high-birefringence fibre (HBF) were altered via bonding a part of HBF to the centric surface of an uniform-strength cantilever beam and applying different stress at end of the beam. As a result, the laser output power could be adjusted and controlled in a dynamic range of more than 33 dB. The laser is not only a controllable and adjustable output-power laser with simple configuration and low cost, but also can be used for optimizing the output characteristics of a linear cavity laser via easily finding out the optimized reflectivity of the reflectors.

To explore the immunoregulating effects of cefodizime on neutrophils and its mechanisms, we detected the expression of some cytokines secreted by neutrophils after heat-killed Klebsiella pneumoniae induced inflammation. We analyzed the changes of signal transduction in this process by detecting the mRNA expression of toll like receptor 4 (TLR4) and the inhibitor factor of kappaBalpha (I-kappaBalpha) expressed by neutrophils. The activity of nuclear factor kappaB (NF-kappaB) in neutrophils was also assayed by electrophoretic mobility shift assay (EMSA). We found cefodizime increased neutrophil production of TNF-alpha, IL-1beta in the early stage of inflammation, which was in agreement with the enhanced mRNA expression of TLR4 and DNA-binding activity of NF-kappaB. Taken together, the immunomodulating effects of cefodizime on cytokine production of K. pneumoniae stimulated neutrophils is possibly due to its regulation of TLR4 mRNA expression and DNA binding activities of NF-kappaB through the LPS-TLR4-NF-kappaB pathway.

The isolation, culture and the active determination of poplar ice nucleation active (INA) bacteria and the inoculation tests in laboratory and field were conducted, and the varieties, distribution and number of poplar INA bacteria and its pathogenicity and freezing injury property were determined. The study results showed that the INA bacteria widely spread on poplar in Northeast China and caused the frozen injury for poplar under the frost condition in Spring or Autumn, which was the key factor to induce INA bacterial canker. Through evaluation and investigation of different poplar varieties and inoculation tests, fine disease-resistant varieties and strains of poplar suitable for Northeast China were selected. Further tests for strong seedling showed that burying cuttings in sand and covering with plastic film could effectively avoid the frostbite, frozen and drought damage, reduce INA bacteria infection, and promote poplar growth. INA bacterial canker was detected early by highly specialized antiserums of INA bacteria and the agglutinated test of ring-shaped boundary surface. The inducers such as streptomycin, phenylmercuric acetae, salicylic acid and heat-killed bacteria to immerse cuttings, have obvious induced disease-resistant effect. Before poplar sprouted in early spring, through spraying the solution of frostbite agent, the control effect also was obvious.

Alpha-lipoic acid (ALA), occurring naturally in human food, is known to possess antioxidative and anti-inflammatory activities. Induction of heme oxygenase-1 (HO-1) has been reported to exhibit a therapeutic effect in several inflammatory diseases. The aim of study was to test the hypothesis that the protection of ALA against lipopolysaccharide-(LPS-) induced acute lung injury (ALI) is mediated by HO-1. Pre- or posttreatment with ALA significantly inhibited LPS-induced histological alterations of ALI, lung tissue edema, and production of proinflammatory cytokine, cytokine inducible neutrophil chemoattractant-3, and nitrite/nitrate in bronchoalveolar lavage fluid. In addition, the inflammatory responses including elevation of superoxide formation, myeloperoxidase activity, polymorphonuclear neutrophils infiltration, nitrotyrosine, inducible nitric oxide synthase expression and nuclear factor-kappa B (NF-κB) activation in lung tissues of LPS-instilled rats were also markedly reduced by ALA. Interestingly, treatment with ALA significantly increased nuclear factor-erythroid 2-related factor 2 (Nrf2) activation and HO-1 expression in lungs of ALI. However, blocking HO-1 activity by tin protoporphyrin IX (SnPP), an HO-1 inhibitor, markedly abolished these beneficial effects of ALA in LPS-induced ALI. These results suggest that the protection mechanism of ALA may be through HO-1 induction and in turn suppressing NF-κB-mediated inflammatory responses.

All-fibre high power erbium–ytterbium co-doped double clad fibre lasers are proposed and demonstrated. By using different back-cavity mirrors, the different double clad fibre lasers are constructed. It is experimentally found that the output behaviour of laser can be controlled by a back-cavity mirror. The lower the reflectivity of the back-cavity mirror, the higher the output power and the high the slop efficiency. The maximum output power is about 1.6 W and the slop efficiency is 27.6%.

A polarization controlled switchable multiwavelength erbium-doped fibre laser with overlapping cavities is proposed. The wavelengths are specified by two Bragg gratings in polarization-maintaining PANDA fibre. The proposed laser can be designed to be operated in stable four-wavelength or wavelength switching modes only by simple adjustment of two polarization controllers. For wavelength switching, four single-wavelength, six dual-wavelength, and four three-wavelength operations have been obtained. The minimum wavelength spacing is only about 0.4 nm.

We study the pulsed laser ablation of wurtzite gallium nitride (GaN) films grown on sapphire, using the femtosecond laser beam at a central wavelength of 800 nm as the source for the high-speed ablation of GaN films. By measuring the backscattered Raman spectrum of ablated samples, the dependence of the ablation depth on laser fluence with one pulse was obtained. The threshold laser fluence for the ablation of GaN films was determined to be about 0.25 J/cm2. Laser ablation depth increases with the increasing laser fluence until the amount of removed material is not further increased. The ablated surface was investigated by an optical surface interference profile meter.

'Methylamine irisolidone' (=5,7-dihydroxy-6-methoxy-3-(4-methoxyphenyl)-8-[(methylamino)methyl]-4H-[1]benzopyran-4-one), a new compound, is a structurally modified kakkalide with good water solubility. In this study, we investigated its effect on hypoxia/reoxygenation (H/R) injury in cultured rat cardiac myocytes. The results showed that methylamine irisolidone could significantly inhibit lactate dehydrogenase (LDH) release, enhance the mitochondrial membrane potential, decrease intracellular calcium (Ca(2+)) associated with the attenuation of reactive oxygen species (ROS) generation, reduce contents of malondialdehyde (MDA), and increase the activity of superoxide dismutase (SOD) after H/R in a dose-dependent manner. The present study demonstrated that methylamine irisolidone can directly protect cardiomyocytes against H/R injury, primarily as a result of reduction of the intracellular Ca(2+) overload coincident with an attenuation of ROS generation and ROS-mediated lipid peroxidation, which may contribute to the preservation of mitochondrion function and antioxidant against H/R injury.

Background : Sialic acid, as a terminal saccharide residue on cell surface glycoconjugates, plays an important role in a variety of biological processes. However, the precise nature of the molecules in gastric cancers has not been unveiled nor documented to be of clinical relevance. Herein, we measured the expression of α 2, 3-linked sialic acid residues by using a specific lectin as well as the potential of invasion and metastasis of gastric cancer was analyzed. Methods : The expression of α 2, 3-linked sialic acid residues in 100 cases of gastric cancer samples was evaluated using Maackia amurensis leukoagglutinin (MAL) histochemical staining analysis. The assays of cytochemical staining and flow cytometry were employed to determine the MAL positive cells in the gastric cancer cell lines. The activities of invasion and migration were evaluated using the assays of cell adhesion and transwell chamber. Results : The staining of MAL in gastric cancer tissues showed that high levels of α 2, 3-linked sialic acid residues were closely associated with the invasive depth ( P =0.0003) and lymph node metastasis ( P =0.0441). In gastric adenocarcinoma cell lines, SGC-7901, the highly metastatic cell line, displayed the most positive reaction with MAL among the selected cell lines. The potential of invasion and migration was confirmed using the assays of adhesion and transwell chamber that SGC-7901 exhibited the high activity of adhesion to extracellular matrix (ECM) and penetration to Matrigel. Conclusion : These results suggested that high level of α 2, 3-linked sialic acid residues was associated with metastatic potential of gastric cancer cells.

Salvia plebeia R. Br is a traditional Chinese herb which has been considered as an inflammatory mediator used for treatment of many infectious diseases including hepatitis. Previously, the compound homoplantaginin was isolated in our group. Hence, we evaluated the protective effects of homoplantaginin on hepatocyte injury. Homoplantaginin displayed an antioxidant property in a cell-free system and showed IC(50) of reduction level of DPPH radical at 0.35 microg/ml. In human hepatocyte HL-7702 cells exposed to H(2)O(2), the addition of 0.1-100 microg/ml of homoplantaginin, which did not have a toxic effect on cell viability, significantly reduced lactate dehydrogenase (LDH) leakage, and increased glutathione (GSH), glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) in supernatant. In vivo assay, we employed the model of Bacillus Calmette-Guerin (BCG)/lipopolysaccharide (LPS)-induced hepatic injury mice to evaluate efficacy of homoplantaginin. Homoplantaginin (25-100mg/kg) significantly reduced the increase in serum alanine aminotranseferase (ALT) and aspartate aminotransferase (AST), decreased the levels of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 (IL-1). The same treatment also reduced the content of thiobarbituric acid-reactive substances (TBARS), elevated the levels of GSH, GSH-Px and SOD in hepatic homogenate. The histopathological analysis showed that the grade of liver injury was ameliorated with reduction of inflammatory cells and necrosis of liver cells in homoplantaginin treatment mice. These results suggest that homoplantaginin has a protective and therapeutic effect on hepatocyte injury, which might be associated with its antioxidant properties.

Cation exchange behavior of actinium-228 in mixed solvent system consisting of methanol-thiocyanate-water was studied with Dowex 50 resin. Solvent systems containing 50 to 90% methanol and concentration of thiocyanate from 1F to 5F were used. The distribution ratios of actinium between resin and the solutions were estimated by batch equilibrium and elution peak methods. By plotting these distribution ratios for each solvent system against the concentration of thiocyanate, different correlations were found. The difference may be attributed to the fact that the different species were absorbed by the resin. Feasibitity of using the mixed solvent system to the separation of actinium from thorium, was also examined.

The title isoxazoline N-oxide underwent 1,3-dipolar cycloaddition with a number of electron deficient olefins regiospecifically to give isoxazolizidines. All four possible geometric approaches of addenda leading to successful cycloadditions occurred to give mixtures of products. A pressure at 1-2 KBar did accelerate the rate of the 1,3-dipolar cycloadditions significantly without improving the selectivity of geometrical orientations of approaches: the poor selectivity was ascribed to the lack of ground state molecular association in solution