Despite the effectiveness of carbon fibre reinforced polymers (cFRPs) and steel braces equipped with hysteretic dissipative devices (HYDBs) to improve the seismic performance of r.c. framed structures, the only use of...
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Despite the effectiveness of carbon fibre reinforced polymers (cFRPs) and steel braces equipped with hysteretic dissipative devices (HYDBs) to improve the seismic performance of r.c. framed structures, the only use of cFRPs may be unsatisfactory for the retrofitting of buildings designed for gravity loads only while HDYBs may be unsuitable without a preliminary upgrading. The use of cFRP and HYDB as a combined technique for the seismic retrofitting of reinforced concrete (r.c.) buildings is investigated herein. To this end, two-, four- and eight-storey r.c. framed structures are designed with reference to the structural codes for r.c. buildings in force in Italy before and after 1971. A computer code for the nonlinear static and dynamic analysis of r.c. framed structures is modified to include cFRPs and HYDBs. Firstly, the nonlinear static analysis of the original test structures is carried with the aim of improving preliminarily strength and displacement capacities by applying cFRPs laminates, at the top and bottom sides of r.c. frame members, and cFRPs wraps, at the critical end zones of columns, respectively. Then, a displacement-based design procedure of HYDBs is adopted to complete the seismic retrofitting, starting from capacity curves of the upgraded test structures. To check the reliability of the combined cFRP-HYDB technique, nonlinear dynamic analysis of the original and retrofitted structures is performed considering two sets of seven near- and far-fault ground motions scaled to the seismic design level. Results highlight that the insertion of the HYDBs is effective in reducing the seismic demand of previously upgraded cFRP structures, with Post71 types generally performing better than Ante71 ones.
The Li4Ti5O12/ccomposites were synthesized by one-step solid-phase reaction using metatitanic acid, lithium carbonate and sucrose as raw materials. The effects of the molar ratio of lithium to titanium, calcining tem...
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The Li4Ti5O12/ccomposites were synthesized by one-step solid-phase reaction using metatitanic acid, lithium carbonate and sucrose as raw materials. The effects of the molar ratio of lithium to titanium, calcining temperature, calcination time, and sucrose content on the structure of Li4Ti5O12/ccomposites were studied. XRD, SEM, TEM and electrochemical performance tests were used to characterize the results. The results showed that n(Li):n(Ti) = 0.85, calcination temperature was 750 degrees c, calcination time was 6 h, and the sucrose addition amount was 30% of the total mass of raw materials. Under the conditions, the pure Li4Ti5O12/ccomposites can be synthesized. The particles are uniform, the particle size is 0.1-1 mu m, and the carbon envelopment is better. The specificcapacity is up to 163.94 mAh/g at 0.1 c rate, and the theoretical specificcapacity is 175 mAh/g very close.
The stability and cO tolerance of a self-made 20wt% Pt/Ti0.8Mo0.2O2-c mixed oxide-carbon composite supported electrocatalyst was compared to those of a commercial state-of-the-art PtRu/c electrocatalyst by means of cy...
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The stability and cO tolerance of a self-made 20wt% Pt/Ti0.8Mo0.2O2-c mixed oxide-carbon composite supported electrocatalyst was compared to those of a commercial state-of-the-art PtRu/c electrocatalyst by means of cyclic voltammetry and cOads stripping voltammetry measurements. On the Pt/Ti0.8Mo0.2O2-ccatalyst the oxidation of cO takes place at exceptionally low potential values (E-cO,E-onset=50mV);the onset potential is shifted to less positive potentials by 150mV compared to the PtRu/ccatalyst. A stability test involving 500 polarization cycles revealed that the PtRu/ccatalyst suffered more significant degradation than the composite supported Pt catalyst. XPS measurements indicated that the degradation is connected to ruthenium dissolution. At the same time, better electrocatalytic stability and increased cO tolerance of the Pt/Ti0.8Mo0.2O2-c electrocatalyst compared to the PtRu/ccatalyst was evidenced.
The aim of the present study was to evaluate the antifungal activity of seaweed champia parvula and identification of active compounds for this action. In this regard, c. parvula crude extracts were obtained from n-he...
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The aim of the present study was to evaluate the antifungal activity of seaweed champia parvula and identification of active compounds for this action. In this regard, c. parvula crude extracts were obtained from n-hexane, ethyl acetate, chloroform, methanol, and water used to study the antifungal action. Results showed that methanolic extract had potent action against c. albicans, c. tropicalis, T. mentagrophytes, and ***, with the highest inhibition of 16.7 mm found against c. tropicalis. Minimum inhibition concentration at 12.5 and minimum fungal concentration at 25 mu g/mL were found in the methanolic extract. Therefore, to identify the bioactive compound for this antifungal action in the methanolic extract, thin-layer chromatography (TLc) and reverse-phase high-performance liquid chromatography (RP-HPLc) were used. The RP-HPLc had three peaks with retention times at 3.30, 3.86, and 4.73 min, showing the presence of ester fatty acid compound. Further, these compounds were characterized by nuclear magnetic resonance (NMR), gas chromatography (Gc), and liquid chromatography-mass spectrometry (Lc-MS), which showed the presence of long-chain aliphatic fatty acid like eicosanoic acid with formation of oct-1-en-3-ol compounds attached.
To help fill the knowledge gap regarding the potential human health impacts of food pigment TiO2, a comparative toxicity study was performed on a food-grade TiO2 (f-TiO2), a bulk TiO2 (b-TiO2), and a nano-sized TiO2 (...
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To help fill the knowledge gap regarding the potential human health impacts of food pigment TiO2, a comparative toxicity study was performed on a food-grade TiO2 (f-TiO2), a bulk TiO2 (b-TiO2), and a nano-sized TiO2 (Degussa P25), and in the nematode caenorhabditis elegans. Acute phototoxicity and chronic toxicity effects including reproduction, lifespan, and vulval integrity were evaluated. The f-TiO2, b-TiO2, and P25 had a primary particle size (size range) of 149 (53-308) nm, 129 (64-259) nm, and 26 (11-52) nm, respectively. P25 showed the greatest phototoxicity with a 24-h Lc50 of 6.0mg/L (95% cI 5.95, 6.3), followed by the f-TiO2 (Lc50=6.55mg/L (95% cI 6.35, 6.75)), and b-TiO2 was the least toxic. All three TiO2 (1-10mg/L) induced concentration-dependent effects on the worm's reproduction, with a reduction in brood size by 8.5 to 34%. They all caused a reduction of worm lifespan, accompanied by an increased frequency of age-associated vulval integrity defects (Avid). The impact on lifespan and Avid phenotype was more notable for P25 than the f-TiO2 or b-TiO2. Ingestion and accumulation of TiO2 particles in the worm intestine was observed for all three materials by light microscopy. These findings demonstrate that the food pigment TiO2 induces toxicity effects in the worm and further studies are needed to elucidate the human health implication of such toxicities.
Public key cryptosystems based on multivariate polynomials have been studied since the eighties. One of them, called c, was introduced in 1988 by Imai and Matsumoto, and broken in 1993 by Dobbertin in classified work ...
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Public key cryptosystems based on multivariate polynomials have been studied since the eighties. One of them, called c, was introduced in 1988 by Imai and Matsumoto, and broken in 1993 by Dobbertin in classified work he did for the German Federal Office for Information Security and later by Patarin (see Dobbertin et al. 2005, Patarin 1995). Since then, the construction of multivariate systems sharing a great deal of the c properties have become of particular interest. Dobbertin introduced in a series of classified papers and later in a challenge of the MysteryTwister-competition hosted by the Horst-Gortz-Institute in 2005, (see Dobbertin et al. 2005) together with the author, a system where the central mapping is a power mapping of degree 4 and shares almost all the properties of c. It was therefore called biquadraticc. The challenge remained unbroken and the security of these systems an open problem. As its key size is rather large, the interest in such systems became low during the last years. Due to the initiative of the European Telecommunications Standards Institute and the National Institute for Standards and Technology in creating standards for post-quantum cryptography, systems with bigger key sizes have become of interest for practical applications. In this paper we will consider biquadraticc and more general systems based on hidden monomials of degree k called k-ary c. We will prove a lower bound for the running time of attacks based on Grobner basis algorithms like F-4 or F-5. We will compute the first fall degree for k-ary c and give a counterexample to the first fall degree assumption. We will derive an estimate for the complexity of breaking the above mentioned cryptochallenge and give parameter sizes for secure systems by taking into account all known types of attacks. It will turn out that the security requirements yield systems with impractical key sizes even for applications in post-quantum cryptography. Although k-ary c is not of practical inter
Adopting orthogonal experiments, relevant machinability in wire cut electrical discharge machining (WEDM) of 2D c/Siccomposite was studied. The effects of electrical machining parameters (namely pulse width, pulse in...
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Adopting orthogonal experiments, relevant machinability in wire cut electrical discharge machining (WEDM) of 2D c/Siccomposite was studied. The effects of electrical machining parameters (namely pulse width, pulse interval, and the number of tubes) on machining speed and surface roughness were analyzed. In addition, the effect of fiber orientations on the machinability was also studied. The main effect and interaction of the selected electrical machining parameters were also discussed. The key results show that the fiber orientation effect on machining speed plays a weaker role in WEDM of this composite. For machining speed, the number of tubes and the pulse interval have no interaction in both of machining directions A and B. For surface roughness, the number of tubes and the pulse interval have obvious interaction in both of machining directions A and B. The fiber orientation has a larger effect on the surface roughness than that on machining speed in WEDM of this composite. After analyzing the material removal mechanism, some new significant results show that the carbon fibers are removed in the form of transverse and longitudinal fracture. Interfacial debonding between fiber carbon and Sic matrix, pit, and recast layer form on the machined surface. Micro cracks are observed in the carbon fiber, and a part of the micro cracks are cross.
cellular microRNAs(miRNAs) have been shown to modulate HcV infection via directly acting on the viral genome or indirectly through targeting the virus-associated host factors. Recently we generated a comprehensive map...
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cellular microRNAs(miRNAs) have been shown to modulate HcV infection via directly acting on the viral genome or indirectly through targeting the virus-associated host factors. Recently we generated a comprehensive map of HcV–miRNA interactions through genome-wide miRNA functional screens and transcriptomics analyses. Many previously unappreciated cellular miRNAs were identified to be involved in HcV infection, including miR-135a, a human cancerrelated miRNA. In the present study, we investigated the role of miR-135a in regulating HcV life cycle and showed that it preferentially enhances viral genome replication. Bioinformatics-based integrative analyses and subsequent functional assays revealed three antiviral host factors, including receptor interacting serine/threonine kinase 2(RIPK2), myeloid differentiation primary response 88(MYD88), and c-X-c motif chemokine ligand 12(cXcL12), as bona fide targets of miR-135a. These genes have been shown to inhibit HcV infection at the RNA replication stage. Our data demonstrated that repression of key host restriction factors mediated the proviral effect of miR-135a on HcV propagation. In addition,miR-135a hepatic abundance is upregulated by HcV infection in both cultured hepatocytes and human liver, likely mediating a more favorable environment for viral replication and possibly contributing to HcV-induced liver *** results provide novel insights into HcV–host interactions and unveil molecular pathways linking miRNA biology to HcV pathogenesis.
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