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Hemicelluloses, a major component of plant cell walls, are a non-cellulosic heteropolysaccharide composed of several distinct sugars that is second in abundance to cellulose, which are one of the most abundant and cheapest renewable resources on earth. Hemicelluloses structure is complex and its chemical structure varies greatly among the different plant species. In addition to its wide use in production of feed and other chemical materials, hemicelluloses are known for its remarkable biological activities that remain largely underutilised to date. Therefore, comprehensive investigations of hemicelluloses structural and biological properties would be helpful for achieving rational utilisation and high-value conversion of this underutilised substance into agents with enhanced health benefits for incorporation in drugs and health foods. In this review, details of diverse research initiatives that have enhanced our understanding of hemicelluloses properties are summarised, including hemicelluloses sources, extraction and purification methods, structural characteristics and biological activities. Furthermore, hemicelluloses structure-activity relationships and new directions for future hemicelluloses research studies are discussed.

Cylindrospermopsin (CYN) is a toxic secondary metabolite from cyanobacteria that can cause cardiovascular disease. However, the study of CYN-induced cardiovascular toxicity in vitro is very limited and the mechanism is remain to be clarified. Vascular smooth muscle cells (VMSCs) have an important function in maintaining the structural and functional integrity of the aortic wall, and are an important in vitro model for cardiovascular research. Thus, the effects of CYN exposure (2, 20, 200, and 2000 nM) on VMSCs were analyzed. In vitro study, results showed that CYN exposure decreased VMSCs viability, inhibited VMSCs migration, induced DNA damage, destroyed cytoskeleton, changed cell morphology, promoted VMSCs apoptosis, and increased intracellular reactive oxygen species (ROS) levels. In addition, CYN could induce the activities of SOD, CAT and GPX, and promote the expressions of SOD1, CAT, GPx1, p53 and Bax genes and inhibit the expression of Bcl-2 gene, leading to a higher ratio of Bax/Bcl-2. Taken together, CYN may induce ROS overproduction, leading to increased p53 expression and ultimately promoting VSMC apoptosis. Therefore, the present study demonstrates that CYN could impair VMSCs, leading to vascular developmental defects and angiocardiopathy.

Plants establish symbioses with mutualistic fungi, such as arbuscular mycorrhizal (AM) fungi, and bacteria, such as rhizobia, to exchange key nutrients and thrive. Plants and symbionts have coevolved and represent vital components of terrestrial ecosystems. Plants employ an ancestral AM signaling pathway to establish intracellular symbioses, including the legume–rhizobia symbiosis, in their roots. Nevertheless, the relationship between the AM and rhizobial symbioses in native soil is poorly understood. Here, we examined how these distinct symbioses affect root-associated bacterial communities in Medicago truncatula by performing quantitative microbiota profiling (QMP) of 16S rRNA genes. We found that M. truncatula mutants that cannot establish AM or rhizobia symbiosis have an altered microbial load (quantitative abundance) in the rhizosphere and roots, and in particular that AM symbiosis is required to assemble a normal quantitative root-associated microbiota in native soil. Moreover, quantitative microbial co-abundance network analyses revealed that AM symbiosis affects Rhizobiales hubs among plant microbiota and benefits the plant holobiont. Through QMP of rhizobial rpoB and AM fungal SSU rRNA genes, we revealed a new layer of interaction whereby AM symbiosis promotes rhizobia accumulation in the rhizosphere of M. truncatula. We further showed that AM symbiosis-conditioned microbial communities within the M. truncatula rhizosphere could promote nodulation in different legume plants in native soil. Given that the AM and rhizobial symbioses are critical for crop growth, our findings might inform strategies to improve agricultural management. Moreover, our work sheds light on the co-evolution of these intracellular symbioses during plant adaptation to native soil conditions.

Selenium is a trace element that has been shown to inhibit the growth of various cancer cell types. However, its role in cervical cancer and its underlying mechanisms remains largely unknown. Herein, we explored the anti-cervical cancer effect of selenium and its potential mechanisms through xenograft and in vitro experiments. HeLa cell xenografts in female nude mice showed tumor growth retardation, with no obvious liver and kidney toxicity, after being intraperitoneally injected with 3 mg/kg sodium selenite (SS) for 14 days. Compared to the control group, selenium levels in the tumor tissue increased significantly after SS treatment. In vitro experiments, SS inhibited the viability of HeLa and SiHa cells, blocked the cell cycle at the S phase, and enhanced apoptosis. RNA-sequencing, Kyoto encyclopedia of genes and genomes pathway analysis showed that forkhead box protein O (FOXO) was a key regulatory signaling pathway for SS to exhibit anticancer effects. Gene Ontology analysis filtered multiple terms associated with apoptosis, anti-proliferation, and cell cycle arrest. Further research revealed that SS increased intracellular reactive oxygen species (ROS) and impaired mitochondrial function, which activated adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) via phosphorylation at Thr172, resulting in activation of FOXO3a and its downstream growth arrest and DNA damage-inducible alpha (GADD45a). In summary, SS exhibited anti-cervical cancer effects, and their mechanisms may be that SS is involved in inducing cell cycle arrest and potentiating cell apoptosis caused by ROS-dependent activation of the AMPK/FOXO3a/GADD45a axis.

Antisense oligonucleotide (AO) therapy has been the specific treatment for Duchenne muscular dystrophy, with ongoing clinical trials. However, therapeutic applications of AOs remain limited, particularly because of the lack of efficient cellular delivery methods imperative for achieving efficacy. In this study, we investigated a few aminoglycosides (AGs) for their potential to improve the delivery of antisense phosphorodiamidate morpholino oligomer (PMO) both in vitro and in vivo. AGs had lower cytotoxicity compared with Endoporter, the currently most effective delivery reagent for PMO in vitro, and improved efficiency in PMO delivery 9- to 15-fold over PMO alone. Significant enhancement in systemic PMO-targeted dystrophin exon 23 skipping was observed in mdx mice, up to a 6-fold increase with AG3 (kanamycin) and AG7 (sisomicin) compared with PMO only. No muscle damage could be detected clearly with the test dosages. These results establish AGs as PMO delivery-enhancing agents for treating muscular dystrophy or other diseases., Graphical Abstract

Ulcerative colitis (UC) is an idiopathic, chronic inflammatory disorder of the colonic mucosa. Risk of colorectal cancer in ulcerative colitis is increased in patients with long-standing disease compared with the general population. Hericium erinaceus (HE) has been used in traditional folk medicine and medicinal cuisine in China, Korea and Japan with anti-gastritis and anti-ulcerative colitis activities. EP-1, a purified unique polysaccharide isolated from HE mycelium, has recently been identified as the active component responsible for anti- ulcerative colitis activity by using a cell model for identification. In this study, our data shows that EP-1 was effective in relieving the symptoms of acetic acid induced UC rats. Based on the Illumina MiSeq platform, 16S rRNA sequencing of the rat colonic contents indicated that the intestinal flora structure remarkably changed in the model rats and the tendency was alleviated to a certain degree by EP-1. The further results showed that in the acetic acid induced UC rats EP-1 modulated the gut microbiota community and increased short chain fatty acids (SCFAs). And immunoblot analyses showed that after treated by EP-1, GPR41 and GPR43 were significantly suppressed expression in colonic tissues of the UC rats. In the meanwhile, EP-1 also showed its antioxidant, anti-inflammatory and enhancing immune activities. Thus, the polysaccharide purified from HE showed potential for anti-UC activity and the complementary and alternative medicine (CAM) herb therapy.

Aims To evaluate the therapeutic benefits of Hesperidin (Hes) using an imiquimod (IMQ)-induced psoriasis-like mouse model and human immortalized keratinocytes (HaCaT) cells stimulated with lipopolysaccharide (LPS). Methods Mice were treated with IMQ and orally administered Hes (125–500 mg/kg/day), methotrexate (MTX) 1 mg/kg/day or distilled water. HaCaT cells were stimulated with LPS (1 μg/mL) and relevant indices were measured after administration with different concentrations of Hes (5–20 μg/mL) for 24 h. Inflammatory skin lesions in IMQ mice were evaluated using the psoriasis area severity index (PASI) and pathological staining. Proteins in the IRS-1/ERK1/2 pathway and inflammatory factors were assessed using western blotting or quantitative real-time PCR. In addition, factors related to IRS-1 secretion levels were assessed by enzyme-linked immunosorbent assays. Extracellular flux (XF) analysis was used to assess cellular metabolic levels. Key findings Hes significantly improved psoriasis-like skin lesions of IMQ-treated mice and inhibited LPS-induced HaCaT cell proliferation. In addition, Hes remarkably decreased PASI scores, reduced epidermal thickness, decreased proliferation and differentiation of epidermal cells, inhibited mRNA expression of inflammatory factors, reduced local skin lesions and serum insulin and glucose levels. Furthermore, Hes modulated the secretion levels of serum Leptin, Adiponectin and Resistin, and inhibited the activation of the IRS-1/ERK1/2 signaling pathway and regulated HaCaT cells metabolism. Significance This study demonstrated that Hes administration could have significant therapeutic value for the prevention and clinical treatment of psoriasis.

Microcystin-leucine arginine (MC-LR) is a kind of toxin produced by cyanobacteria, which can do harm to human and livestock health. MC-LR can easily enter tissues and organs through the blood circulation and accumulate in certain target organs. Vessels are prone to contact with MC-LR during growth and development. Previous study had demonstrated that MC-LR had potential vascular toxicity. However, it is not clear whether MC-LR has adverse effects on vascular smooth muscle cells. In this study, we evaluated the cytotoxicity of MC-LR exposure (0.01, 0.05, 0.1, 0.5, and 1 μM) on human aortic vascular smooth muscle cells (HAVSMCs) in vitro. The data showed that MC-LR exposure inhibited the HAVSMC proliferation and migration, induced HAVSMC apoptosis, cytoskeleton destruction, S-phase arrest, mitochondrial transmembrane potential (MMP) loss, and reactive oxygen species (ROS) production. In addition, MC-LR exposure resulted in the imbalance between oxidants and antioxidants, increased the caspase-3 and caspase-9 activities, and down-regulated the gene expressions (integrin β1, Rho, ROCK, MLC). Taken together, MC-LR could induce the generation of ROS in HAVSMCs, leading to apoptosis by the mitochondrial signaling pathway. MC-LR could also induce cytoskeletal disruption by integrin-mediated FAK/ROCK signaling pathway, leading to cell cycle arrest and the inhibition of HAVSMCs proliferation and migration. The current findings facilitate an understanding of the mechanism of MC-LR toxicity involved in angiocardiopathy.

As a newly-invented and highly-efficiency strobilurin fungicide, pyraoxystrobin (SYP-3343) has been recognized as a highly poisonous toxin for a variety of aquatic organisms. Nevertheless, the developmental toxicity and potential mechanism of SYP-3343 have not been well-documented. The results showed that SYP-3343 was relatively stable and maintained within the range of 20 % in 24 h, and the LC

It has been demonstrated by human genetics that the voltage-gated sodium channel Nav1.7 is currently a promising target for the treatment of pain. In this research, we performed molecular simulation works on a series of classic aryl sulfonamide Nav1.7 inhibitors using three-dimensional quantitative structure-activity relationships (3D-QSAR), molecular docking and molecular dynamics (MD) simulations for the first time to explore the correlation between their structures and activities. The results of the relevant statistical parameters of comparative molecular field analyses (CoMFA) and comparative molecular similarity indices analyses (CoMSIA) had been verified to be reasonable, and the deep relationship between the structures and activities of these inhibitors was obtained by analyzing the contour maps. The generated 3D-QSAR model showed a good predictive ability and provided valuable clues for the rational modification of molecules. The interactions between compounds and proteins were modeled by molecular docking studies. Finally, accuracy of the docking results and stability of the complexes were verified by 100 ns MD simulations. Detailed information on the key residues at the binding site and the types of interactions they participate in involved was obtained. The van der Waals energy contributed the most in the molecular binding process according to the calculation of binding free energy. All research results provided a good basis for further research on novel and effective Nav1.7 inhibitors.

Objectives Indirubin (IR) is a bisindole compound extracted from the leaves of Chinese herb Indigo Naturalis. Indigo Naturalis has been widely used in traditional Chinese medicine to treat inflammatory and autoimmune diseases. Psoriasis is a chronic immune-mediated inflammatory skin disease in which γδ T cells play an important role. This study aims to determine the immunoregulatory effects and the underlying mechanisms of Indirubin in psoriasis-related inflammatory responses. Methods BALB/c mice with imiquimod (IMQ)-induced psoriasis-like dermatitis were treated with saline (Model), 1 mg/kg methotrexate (MTX) that serves as a positive control, or 12.5, 25 and 50 mg/kg Indirubin(IR) intragastrically. Keratinocytes proliferation, inflammatory cells infiltration, the expression of inflammatory cytokines and Jak/Stat pathway-related proteins in the skin lesion were examined. The abundance of γδ T cells in lymph nodes and spleen was determined by flow cytometry. The IL-17 expression and secretion, and the activation of Jak3/Stat3 pathways in in vitro cultured γδ T cell were tested. Results Indirubin ameliorated keratinocyte proliferation, reduced the infiltration of CD3+ T cells, IL-17 A-producing γδ T cells, and CD11b+ neutrophils, inhibited the mRNA expression of Il1, Il6, Il23, Il17a and Il22, and the protein expression of Jak/Stat pathway-related molecules in the skin lesion. Indirubin also reduced the abundance of γδ T cell and CCR6+ γδ T cells (the major IL-17 A producer) in spleen and lymph nodes. In cultured γδ T cells, Indirubin inhibited the mRNA expression of Il17a and Ifng, and the secretion of IL-17 A, while suppressed the activation of Jak3/Stat3 pathways. Conclusion Indirubin alleviates IMQ-induced psoriasis-like dermatitis mainly through reducing the inflammatory responses mediated by IL-17 A-producing γδ T cells involving Jak3/Stat3 activation. Our results highlighted the novel mechanisms by which Indirubin ameliorates psoriasis-related inflammatory responses, supporting its therapeutic potential.

Aims Psoriasis vulgaris is mediated by T and dendritic cells. This study aimed to investigate the effects of acetyl-11-keto-β-boswellic acid (AKBA) on activated dendritic cells (DCs) using an imiquimod (IMQ)-induced psoriasis-like mouse model and murine bone marrow–derived dendritic cells (BMDCs) stimulated with resiquimod (R848) in vitro. Materials and methods The mice were treated with IMQ and intragastrically administered 25–100 mg/kg/day of AKBA, 1 mg/kg/day of methotrexate (MTX), or normal saline. The inflammation of skin lesions in IMQ mice were evaluated by psoriasis area and severity index (PASI) and pathological staining. The related proteins of Toll-like receptor (TLR)7/8 pathways were assessed using Western blotting, and the expression levels of interleukin (IL)-23 and IL-12p40 mRNA using reverse transcription–polymerase chain reaction. The numbers of DCs and marker-positive BMDCs were assessed using flow cytometry and the levels of inflammatory factors using the enzyme-linked immunosorbent assay. Key findings AKBA and MTX obviously improved the psoriasis-like skin lesions of IMQ-treated mice. AKBA also obviously decreased the PASI score, reduced the thickness of epidermis, ameliorated the infiltration of CD3+ and CD11c+ cells in skin lesions, decreased the activation of local DCs, inhibited the mRNA expression and secretion of inflammatory factors IL-12 and IL-23, inhibited the maturation and differentiation of DCs to promote T-cell differentiation, and inhibited the activation of TLR7/8 and IRF signaling pathways. Significance This study implied that AKBA might have an anti-inflammatory effect on psoriasis by inhibiting the maturation and activation of DCs via the TLR8 and IRF signaling pathways.

The microstructures and corrosion resistances of hypoeutectic Al-6.5Si-0.45 Mg casting alloys with addition of both Sc and Zr were investigated by using scanning electron microscope, X-ray diffraction, electrochemical measurement techniques and immersion corrosion tests. The results show that the addition of lower content of Sc has some modifying effect on the eutectic Si phases, but doesn't exhibit obvious refining action on the primary α (Al) phases of the alloy. The combined addition of both Sc and Zr can enhance the refining and modifying effects of Sc, and transform the primary α(Al) phases to equiaxed crystal, and the eutectic Si phases to the fine granular shapes. The corrosion resistance of the test alloys is firstly weakened, and then recovered, to some extent, with the increase of the exposure time in the 3.5 wt%NaCl solution. The test alloys with fine eutectic Si have poorer corrosion resistance than the test alloys with coarse eutectic Si. The formation of more galvanic couplings in the test alloys with fine eutectic Si is responsible for the poor corrosion resistance. The immersion corrosion rate of the test alloys with fine eutectic Si is higher than that of the test alloys with coarse eutectic Si. This is consistent with the results of the electrochemical corrosion studies. The corrosion of the alloys mainly occurs in the eutectic region, and the eutectic α(Al) phases are dissolved. It indicates that the Si phase is more noble than the α(Al) phase, and the galvanic couplings can be formed between the eutectic Si and α(Al) phases.

The establishment of the symbiotic interaction between rhizobia and legumes involves the Nod factor signaling pathway. Nod factor recognition occurs through two plant receptors, NFR1 and NFR5. However, the signal transduction mechanisms downstream of NFR1-NFR5-mediated Nod factor perception remain largely unknown. Here, we report that a small guanosine triphosphatase (GTPase), GmROP9, and a guanine nucleotide exchange factor, GmGEF2, are involved in the soybean-rhizobium symbiosis. We show that GmNFR1α phosphorylates GmGEF2a at its N-terminal S86, which stimulates guanosine diphosphate (GDP)-to-GTP exchange to activate GmROP9 and that the active form of GmROP9 can associate with both GmNFR1α and GmNFR5α. We further show that a scaffold protein, GmRACK1, interacts with active GmROP9 and contributes to root nodule symbiosis. Collectively, our results highlight the symbiotic role of GmROP9-GmRACK1 and support the hypothesis that rhizobial signals promote the formation of a protein complex comprising GmNFR1, GmNFR5, GmROP9, and GmRACK1 for symbiotic signal transduction in soybean.

Resists are important multicomponent system require in microelectronic industry for fabrication of integrated circuit (IC) devices. The current high end IC (integrated circuit) technology node in manufacturing is 20 nm and looking toward 16 and 10 nm nodes to fulfil market demand. A series of chemically amplified resists (CARs) based on co and terpolymers of 4-hydroxystyrene (HOST), 2-ethyl-2-adamantyl methacrylate (EAMA) and/or a monomer-bound anionic photoacid generator (PAG) were prepared and characterized. Specifically, Triphenylsulfonium salt 4-(methacryloxy)-2,3,5,6-tetrafluorobenzenesulfonate (F4 PAG) was incorporated into the main chain to get PAG bound polymer microstructure. The aim of the study was to investigate interplay of individual monomers in co and terpolymer systems. This was achieved by understanding the reactivity ratios and monomer sequence distribution in the polymer. Analysis was conducted by using a software PROCOP version2.3. The co/terpolymer compositions were determined by quantitative 1 H NMR spectra. The copolymer reactivity ratio of each monomer was determined with Fineman–Ross, Kelen–Tudos, and nonlinear least-squares curve- fitting methods. It was observed that EAMA is not polymerizable under given reaction conditions and copolymerization of EAMA-PAG was also not possible. HOST-EAMA system yielded reactivity ratios near zero indicating that they form quasi alternating structures. HOST-PAG system yielded copolymers rich in PAG. On the basis of the reactivity ratios determined from the binary copolymers, Alfrey–Goldfinger equations were used to estimate the compositions of the terpolymers. In terpolymer system, where two monomers were non homopolymerizable, both PAG and EAMA competed to add up to the HOST radical. All six reactivity values were less then unity indicating preferred cross propagation of radicals. PAG was the most reactive monomer. Monomer sequence distribution of copolymer and terpolymer was established to get an idea of detailed microstructure of the chain. Copolymers confirmed 84% of dyads formation of each monomer while terpolymer analysis revealed dominance of HOST centered triads. In addition to this, kinetics of terpolymerization reaction was performed to validate the theory. Findings from the study can be used to tailor make CAR synthesis for optimum EUV (extreme ultraviolet) lithography performance.

In this work, a novel strategy for high-quality AlN templates epitaxy on sapphire substrates with sputtered buffer layers combined with a low- and high-temperature alteration technique is proposed. The best full width at half maximum values for (0002) and (1 1 ¯ 02) reflections are 207 and 377 arcsec, respectively. Investigations indicate the joint effect of growth mode control and sputtered buffer layer results in the improvement of AlN crystalline quality. Firstly, threading dislocations density can be significantly decreased due to the alteration from three-dimensional to two-dimensional growth mode. Moreover, the graded composition of AlON layer in the sputtered buffer layer is believed to alleviate lattice mismatch between sapphire substrates and AlN, which also contributes to low dislocations density in AlN templates.

Double peaks at wavelength of 276 and 290 nm are observed for AlGaN/AlGaN multiple quantum wells (MQWs). Cathodoluminescence (CL) mappings identify that the emission at 290 nm originates from the macrostep edges. Potential minima induced by local variation of QW thickness and Ga incorporation are found along the step edges, where quantum wires (QWRs) are formed. The lateral advance rate of macrostep (∼310 nm/h) is obtained by investigating the distribution of QWRs. Temperature-dependent CL spectrum suggest that thermal quenching for 290 nm emission is dramatically suppressed compared with that for conventional QWs emission, which shows excitonic localization characteristics of QWRs.

The versatility of Hsp90 can be attributed to the variety of co-chaperone proteins that modulate the role of Hsp90 in many cellular processes. As a co-chaperone of Hsp90, Cpr7 is essential for accelerating the cell growth in an Hsp90-containing trimeric complex. Here, we report the crystal structure of Cpr7 at a resolution of 1.8Å. It consists of an N-terminal PPI domain and a C-terminal TPR domain, and exhibits a U-shape conformation. Our studies revealed the aggregation state of Cpr7 in solution and the interaction properties between Cpr7 and the MEEVD sequence from the C-terminus of Hsp90. In addition, the structure and sequence analysis between Cpr7 and homologues revealed the structure basis both for the function differences between Cpr6 and Cpr7 and the functional complements between Cns1 and Cpr7. Our studies facilitate the understanding of Cpr7 and provide decent insights into the molecular mechanisms of the Hsp90 co-chaperone pathway.

A water-soluble polysaccharide (EPA-1) from Pleurotus eryngii was obtained using DEAE-52 and Sephadex G-50 columns. The properties, structure and immunomodulatory activity of EPA-1 were studied. The results demonstrated that EPA-1 was a homogeneous polysaccharide with the molecular weight of 9.97×104Da. EPA-1 consisted of Man, Glc and Gal in a molar ratio of 2.2:1.0:3.2. The characterized fragment structures of EPA-1 were found to be consisting of seven sugar residues and two branches by GC-MS, FTIR and NMR analyses. Among them, the (1→6)-linkedGal residue was the main linkage mode of EpA-1 and composed of its backbone. Activity tests indicated that EPA-1 significantly induced macrophage to release the immune activity factor of NO, TNF-α, IL-1 and IL-6 through activation of signal protein of p38, ERK, JNK in MAPKs and translocation of nuclear NF-κΒ, indicating EPA-1 to possess good immunoregulatory activity.

Three-dimensional graphene/Ni 3 S 2 (3DG/Ni 3 S 2 ) composite electrodes were produced by a facile two-step synthesis route involving chemical vapor deposition (CVD) growth of graphene foam and in situ hydrothermal synthesis of Ni 3 S 2 . The porous structure of the prepared 3DG is ideal for use as a scaffold for fabricating monolithic composite electrodes. The relative content of Ni 3 S 2 initially increased and then decreased with increasing hydrothermal reaction time. The basal surface of the electrode was completely covered after 6 h of hydrothermal reaction. The size of the Ni 3 S 2 microspheres also increased with increasing hydrothermal reaction time. The composite electrodes exhibited good specific capacitance (11.529 F cm −2 at 2 mA cm −2 , i.e., 2611.9 F g −1 at 5 mV s −1 ) and cyclability (retention of 88.97% capacitance after 1000 charge/discharge cycles at 20 mA cm −2 ). These results are attributed to the fact that the uniform distribution of the Ni 3 S 2 microspheres increased the specific surface area of the electrode and facilitated electron transfer and ion diffusion. The 3D multiplexed and highly conductive pathways provided by the defect-free graphene foam also ensured rapid charge transfer and conduction to improve the rate capability of the supercapacitors.

This paper sheds considerable light on the potential of using cast steel technology for seismic-resistant H-beam to tubular column joints. The considered cast modular joint was an integral assembly of joint zone, beam linking zone, and column linking zone, and the joint geometry was carefully designed to overcome some fracture-related issues that conventional joints may have. The research commenced with a set of tensile and cyclic coupon tests for a comprehensive understanding of the material properties of the entire cast modular joint at different key locations, where the material generally showed sufficient ductility, pronounced strain hardening, consistent yield and ultimate strengths, and plump hysteretic response. The following sub-frame tests covered two types of cast modular joints (Type-A and Type-B) with two column load ratios for each joint type. Each specimen represented a typical sub-frame consisting of a cast modular joint and connecting beams and columns. All the specimens exhibited good ductility and energy dissipation ability. No facture was observed at the welding zone which was relocated away from the column face, and as a result, ductile fracture was delayed to occur within the cast modular joint at very large drifts. Moreover, the shear deformation of the panel zone was sufficiently mobilised, and the energy dissipation mechanism of the sub-frame was featured by a combined action of panel zone in shear and beam section in flexural yielding. The codified design expressions for the strength and stiffness of the specimens were also revisited, and design comments were finally made.

The occurrence of cyanobacterial toxins is being increasingly reported. Nodularins (NODs) are one of the cyanotoxins group mainly produced by Nodularia spumigena throughout the world. NODs may exert adverse effects on animal and human health, and NOD-R variant is the most widely investigated. However, research focused on them is still limited. In order to understand the realistic risk well, the aim of this review is to compile the available information in the scientific literature regarding NODs, including their sources, distribution, structural characteristics, physicochemical properties, biosynthesis and degradation, adverse effects in vitro and vivo, and toxicokinetics. More data is urgently needed to integrate the cumulative or synergistic effects of NODs on different species and various cells to better understand, anticipate and aggressively manage their potential toxicity after both short- and long-term exposure in ecosystem, and to minimize or prevent the adverse effects on human health, environment and the economy.

To characterize the features of particle apparent density and its correlation with chemical composition and meteorological conditions, continuous measurements of particle number size distributions and particle mass concentrations were conducted in the winter and summer periods in Beijing using a Scanning Mobility Particle Sizer and a Tapered Element Oscillating Microbalance with a Filter Dynamic Measurement System. The apparent density, as determined by the particle mass to volume ratios, showed strong seasonal and diurnal variations, with higher values were observed during the warm season (1.60 ± 0.43 g cm−3, July to September 2014) compared to the cold season (1.41 ± 0.40 g cm−3, November 2013 to January 2014). A minimum in the morning and afternoon rush hours was observed in both seasons, representing fresh primary aerosol emissions, which were related to soot particles with low density due to their agglomerate structure, especially observed in the late afternoon hours of the cold season (approximately 1.3 g cm−3) when traffic emissions combined with the coal combustion for heating supply. The highest values were found during midday (approximately 1.8 g cm−3) in the warm season, likely due to increased secondary particle production and the presence of more aged particles with a build-up of the convectively mixed boundary layer. The apparent particle density has the potential to serve as a crude tracer for chemical composition and atmospheric processing and might play an important role when considering the associations between health effects and ambient particles.

A polysaccharide named EP-1 was found by screening cultured mycelium of Hericium erinaceus, which was extracted and subjected to precipitation with ethanol, hollow-fiber ultrafiltration and ion-exchange chromatography. The polysaccharide has a molecular weight of approximately 3100Da and is composed of glucose, mannose and galactose, thus being a heteroglycan. EP-1 has a backbone of α-d-Glc(1→3) and β-d-Glc(1→3). The β-d-Glc(1→3) and α-d-Gal-(1→3) were regarded as branches attached to the C-4 position. The α-d-Man was regarded as a terminal residue. The anti-CAG activity was evaluated in experimental systems using a cell model for identification. The polysaccharide significantly inhibited the growth of MC cells obtained from human gastric mucosa epithelium (GES-1) cells transformed by MNNG, which were used as a chronic atrophic gastritis cell model. It also interfered with the MC cells by inducing cell cycle arrest. Thus, EP-1 shows potential for the development of new functional foods and drugs.

The control of stress, growth mode, and morphology in n-Al0.5Ga0.5N grown by metal-organic chemical vapor deposition (MOCVD) were systematically investigated. A 2-μm-thick completely relaxed n-Al0.5Ga0.5N was obtained by adjusting the structure of AlN/Al0.5Ga0.5N superlattices. N-Al0.5Ga0.5N showed an excellent 2D growth at a growth rate of 0.55 µm/h. An almost pit-free surface was realized by lowering the V/III ratio. Finally, the electron concentration and mobility of the optimized n-Al0.5Ga0.5N reached up to 4.2×1018 cm−3 and 48.2 cm2/(V s), respectively. The MQWs grown on the optimized n-Al0.5Ga0.5N demonstrated an outstanding internal quantum efficiency of 47% at 283 nm.

The positive and negative displacement field experiments have achieved good yield increase. The existing researches mainly focus on the microscopic mechanism site and reservoir non-homogeneity. At present, there is no relevant research on the change of crude oil state, quantitative statistical analysis and stimulation mechanism caused by positive and negative displacement in core scale. In this research, the core is subjected to positive and negative displacement and then imaged by quasi-real-time CT scan. The pore network model software is used to quantitatively analyze the oil-water distribution information at different moments in the core. Furthermore, the characteristics of reservoir pores, oil and water occurrence characteristics, positive and negative displacement increased mechanisms and seepage characteristics are clarified. From the study, it is observed that during the whole water flooding process, the volume fraction of the cluster flow gradually decreases. The cluster flow is continuously displaced or broken into other discontinuous phase flow states; multi-porous, columnar, droplet, membranous as a discontinuous phase. The volume percentage increases with the progress of the displacement process, and the increase of multi-porous flow is most obvious during the reverse drive process. The significant reduction of cluster flow during the anti-drive process is the main mechanism for anti-drive production.

A kind of joining method for magnesium alloys, rotation friction pressing riveting (RFPR), is proposed in this paper. In RFPR operation, a rivet with a plug rotating at high speed is brought to contact with the riveted sheets, generating frictional heat between the rivet and riveted sheets, which softens the sheet materials and enables the rivet to be drilled into the sheets under reduced force. When fully inserted, the rivet is stopped rotating, and the plug is immediately pressed into the shank of the rivet by a punch. The expansive deformation of the rivet shank occurs under the action of the plug, thereby forming a mechanical interlock between the rivet and the sheets to fasten the sheets together. The studies show that RFPR of AZ31 magnesium alloy sheet can be carried out at ambient temperature, and provides the joints with superior shear strength and fatigue property when compared with self-piercing riveting (SPR). The effects of the operating parameters of RFPR process on the quality of the joints were investigated in the study. The results shows that while the rivet rotation speed little affects the shear strength of RFPR joints, the punch pressure has a significant influence on the mechanical properties of the RFPR joints. A numerical analysis was also performed to understand the effect of the punch pressure on the interlock between the rivet and the sheets, and the stress and strain distribution inside the sheet materials around the rivet. The results show that the interlock increased with the punch pressure and there is residual compressive stress inside the sheet materials, which seems to explain the good fatigue property of RFPR joints observed.

In this study, the effect of hot humid environmental exposure prior to and after adhesive curing on the fatigue crack growth (FCG) behavior of adhesive-bonded aluminum A356 joints was investigated by using single-edge notch bend (SENB) specimen. The results showed that while the exposure after adhesive curing had a significant effect on the FCG resistance of the joints, the exposure of the assembled joints prior to adhesive curing had a relatively small influence. In addition, the effect of load ratio R on the FCG behavior of the exposed joints was studied. The results showed that the FCG of the exposed joints is more sensitive to load ratio R than that of the unexposed joints.

Coupling with bionic principles, an attempt to improve the wear resistance of ball bearing steel (GCr15) with biomimetic units on the surface was made using a pulsed Nd: YAG laser. Air and water film was employed as processing medium, respectively. The microstructures of biomimeitc units were examined by scanning electron microscope and X-ray diffraction was used to describe the microstructure and identify the phases as functions of different mediums as well as water film with different thicknesses. The results indicated that the microstructure zones in the biomimetic specimens processed with water film were more refined and had better wear resistance increased by 55.8% in comparison with that processed in air; a significant improvement in microhardness was achieved by laser surface melting. The application of water film provided considerable microstructural changes and much more regular grain shape in biomimetic units, which played a key role in improving the wear resistance of ball bearing steel. (c) 2010 Elsevier B.V. All rights reserved.

The effect of Sb on the microstructure and mechanical properties of Mg2Si/Al-Si composites was investigated. The results show that Sb can improve the microstructure and mechanical properties of Mg2Si/AI-Si composites. When the content of Sb is 0.4%, the morphology of primary Mg2Si changes from dendrites to fine particles, the average size of Mg2Si particles is refined from 52 to 25μm, and the ultimate tensile strength and elongation of the composites increase from 102.1 MPa and 0.26% to 138.6 MPa and 0.36%, respectively. The strengthening mechanism can be attributed to the fine-grain strengthening. However, excessive Sb is disadvantageous to the modification of the composites.

This paper focuses on improving the thermal fatigue resistance on the surface of vermicular cast iron coupling with inserted H13 steel blocks that had different cross sections, by cast-in processing. The microstructure of bionic units was examined by scanning electron microscope. Micro-hardness and thermal fatigue resistance of bionic samples with varied cross sections and spacings were investigated, respectively. Results show that a marked metallurgical bonding zone was produced at interface between the inserted H13 steel block and the parent material - a unique feature of the bionic structure in the vermicular cast iron samples. The micro-hardness of the bionic samples has been significantly improved. Thermal resistance of the samples with the circular cross section was the highest and the bionics sample with spacing of 2 mm spacing had a much longer thermal fatigue life, thus resulting in the improvement for the thermal fatigue life of the bionic samples, due to the efficient preclusion for the generation and propagation of crack at the interface of H13 block and the matrix. Crown Copyright (c) 2010 Published by Elsevier Ltd. All rights reserved.

The effects of superheating temperature on the grain refining efficiency of Ti existing in electrolytic low-titanium aluminum (ELTA) without and with the Al-4B addition and the Al-5Ti-1B master alloy in pure Al were comparatively investigated. The results show that the Ti existing in ELTA without Al-4B addition exhibits a certain grain refining efficiency when the melt superheating temperature is lower, but the efficiency decreases rapidly when the superheating temperature is higher. The grain refining efficiency of the Al-5Ti-1B master alloy is better than that of the Ti existing in ELTA without Al-4B addition at any superheating temperature, but it also decreases obviously with the increase of the superheating temperature. One important reason is that the TiB 2 particles coming from the Al-5Ti-1B master alloy can settle down at the bottom of the Al melt easily when the superheating temperature is increased, thus decrease the number of the potent heterogeneous nuclei retained in the Al melt. If the Al-4B master alloy is added to the ELTA melt, the grain refining efficiency of the Ti existing in ELTA can be improved significantly, and does not decrease with the increase of the superheating temperature. This perhaps provides us a possible method to suppress the effect of the superheated melt on the microstructures of aluminum..

Exon skipping has demonstrated great potential for treating Duchenne muscular dystrophy (DMD) and other diseases. We have developed a drug-screening system using C2C12 myoblasts expressing a reporter green fluorescent phosphate (GFP), with its reading frame disrupted by the insertion of a targeted dystrophin exon. A library of 2,000 compounds (Spectrum collection; Microsource Discovery System) was screened to identify drugs capable of skipping targeted dystrophin exons or enhancing the exon-skipping effect by specific antisense oligomers. The 6-thioguanine (6TG) was effective for inducing skipping of both human dystrophin exon 50 (hDysE50) and mouse dystrophin exon 23 (mDysE23) in the cell culture systems and increased exon skipping efficiency (more than threefolds) when used in combination with phosphorodiamidate morpholino oligomers (PMO) in both myoblasts and myotubes. Guanine and its analogues were unable to induce detectable skipping of exon 23 when used alone but enhanced PMO-induced exon skipping significantly (approximately two times) in the muscles of dystrophic mdx mouse in vivo. Our results demonstrate that small-molecule compounds could enhance specific exon skipping synergistically with antisense oligomers for experimental therapy to human diseases.

CuCrFeNiMn alloy system with different elemental contents is synthesized by using the arc melting and casting method. Effect of elemental interaction on microstructure of these alloys is investigated by means of Ni equivalent and Cr equivalent. The alloys exhibit quite simple solid solution phases with FCC or FCC + BCC mixed structures. Bimodal distribution and peak shift in XRD patterns resulted from the lattice constants difference of FCC phase are observed in most alloys. The formation of simple solid solution phase is associated with the slight difference in atomic size and properly mixing enthalpy. The Cu, Mn, Cr and Fe are mostly segregated in dendrite or interdendrite regions, while the Ni is homogeneously distributed in the alloys. In addition, alloys with higher Ni equivalent principally consist of single FCC phase; while those with higher Cr equivalent are mainly composed of FCC + BCC mixed structures.