A proposed scheme showing the photoredox processes during degradation of gallic acid (GA) in presence of Cu2O–CuO–TiO2 photocatalysts, air and visible light (LEDs).
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•Cu(II) ions ...impregnated on TiO2 produced CuO and Cu2O, after calcination at 400°C.•Optical and electronic properties of TiO2 were improved in the presence of CuxO.•The highest photocatalytic activity was obtained with the 40wt. CuO–TiO2 composite.•A reaction path of gallic acid photocatalytic degradation was proposed.
Coupling TiO2 with narrow band gap semiconductors has been a strategy to obtain visible light active photocatalysts. In this work we present, the characterization and photocatalytic results of high-loaded CuO–TiO2 composites prepared by impregnation of TiO2 powder (Evonik, P25) with copper acetate followed by calcination. The resulting composite materials were characterized by X-ray diffraction, nitrogen adsorption/desorption, UV–vis diffuse reflectance, scanning electron microscopy, X-ray photoelectron spectroscopy and time-resolved microwave conductivity. The photocatalysts were used to degrade gallic acid by using low power ultraviolet and visible light emitting diodes (UV-LED and Vis-LED) as light sources. According to the results, the photocatalytic degradation of the pollutant was efficiently converted to several intermediate products and partially mineralized to CO2 by using visible light. These results were explained in terms of an enhancement of the optical and electronic properties of TiO2 by the presence of Cu2O and CuO phases.
The University of Texas Prestressed Concrete Shear Database (UTPCSDB) was developed and expanded to include 1696 tests reported in North America, Japan, and Europe from 1954 to 2010. The UTPCSDB was ...subsequently used to examine the accuracy and conservativeness of shear design procedures based on different rationales. The results of the examination revealed that design expressions based on the Modified Compression Field Theory (MCFT) yielded the most accurate shear strength estimations for prestressed concrete members that failed in typical shear failure modes. Most of the unconservative estimations that resulted from the use of the MCFT-based design expressions were observed in specimens that failed in shear but exhibited signs of horizontal shear damage or anchorage zone distress. Although the ACI 318-11 detailed method provided slightly less-conservative estimations than the MCFT-based design expressions, these estimations were more accurate than those obtained by using other empirical shear design equations. PUBLICATION ABSTRACT
Myocardial infarction (MI) produces acute changes in strain and stiffness within the infarct that can affect remote areas of the left ventricle (LV) and drive pathological remodeling. We hypothesized ...that intramyocardial delivery of a hydrogel within the MI region would lower wall stress and reduce adverse remodeling in Yorkshire pigs (n = 5). 99mTc-Tetrofosmin SPECT imaging defined the location and geometry of induced MI and border regions in pigs, and in vivo and ex vivo contrast cine computed tomography (cineCT) quantified deformations of the LV myocardium. Serial in vivo cineCT imaging provided data in hearts from control pigs (n = 3) and data from pigs (n = 5) under baseline conditions before MI induction, post-MI day 3, post-MI day 7, and one hour after intramyocardial delivery of a hyaluronic acid (HA)-based hydrogel with shear-thinning and self-healing properties to the central infarct area. Isolated, excised hearts underwent similar cineCT imaging using an ex vivo perfused heart preparation with cyclic LV pressurization. Deformations were evaluated using nonlinear image registration of cineCT volumes between end-diastole (ED) and end-systole (ES), and 3D Lagrangian strains were calculated from the displacement gradients. Post-MI day 3, radial, circumferential, maximum principal, and shear strains were reduced within the MI region (p < 0.04) but were unchanged in normal regions (p > 0.6), and LV end diastolic volume (LV EDV) increased (p = 0.004), while ejection fraction (EF) and stroke volume (SV) decreased (p < 0.02). Post-MI day 7, radial strains in MI border zones increased (p = 0.04) and dilation of LV EDV continued (p = 0.052). There was a significant negative linear correlation between regional radial and maximum principal/shear strains and percent infarcted tissue in all hearts (R2 > 0.47, p < 0.004), indicating that cineCT strain measures could predict MI location and degree of injury. Post-hydrogel day 7 post-MI, LV EDV was significantly reduced (p = 0.009), EF increased (p = 0.048), and radial (p = 0.021), maximum principal (p = 0.051), and shear strain (p = 0.047) increased within regions bordering the infarct. A smaller strain improvement within the infarct and normal regions was also noted on average along with an improvement in SV in 4 out of 5 hearts. CineCT provides a reliable method to assess regional changes in strains post-MI and the therapeutic effects of intramyocardial hydrogel delivery.
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•Developed novel platform to assess left ventricle deformation in vivo and ex vivo.•Local cardiac strains decreased progressively over 7 days in infarcted regions.•Measured linear correlation between local degree of infarction and strain.•Hydrogel injection improved strain in regions bordering the infarct.•Hydrogel injection resulted in less ventricle dilation and larger ejection fraction.
Purpose
Seizures are often followed by a period of transient neurological dysfunction and postictal alterations in cerebral blood flow may underlie these symptoms. Recent animal studies have shown ...reduced local cerebral blood flow at the seizure onset zone (SOZ) lasting approximately 1 h following seizures. Using arterial spin labelling (ASL) MRI, we observed postictal hypoperfusion at the SOZ in 75% of patients. The clinical implementation of ASL as a tool to identify the SOZ is hampered by the limited availability of MRI on short notice. Computed tomography perfusion (CTP) also measures blood flow and may circumvent the logistical limitations of MRI. Thus, we aimed to measure the extent of postictal hypoperfusion using CTP.
Methods
Fourteen adult patients with refractory focal epilepsy admitted for presurgical evaluation were prospectively recruited and underwent CTP scanning within 80 min of a habitual seizure. Patients also underwent a baseline scan after they were seizure-free for > 24 h. The acquired scans were qualitatively assessed by two reviewers by visual inspection and quantitatively assessed through a subtraction pipeline to identify areas of significant postictal hypoperfusion.
Results
Postictal blood flow reductions of > 15 ml/100 g
−1
/min
−1
were seen in 12/13 patients using the quantitative method of analysis. In 10/12 patients, the location of the hypoperfusion was partially or fully concordant with the presumed SOZ. In all patients, additional areas of scattered hypoperfusion were seen in areas corresponding to seizure spread.
Conclusion
CTP can reliably measure postictal hypoperfusion which is maximal at the presumed SOZ.
The use of innovative lightweight materials for structural design in the automotive industry is no longer a novelty. When joining different parts made of these new materials it is clear that ...adhesives are one of the best solutions. However, the selection of a suitable adhesive for this application and the performance of the joint under real car conditions need to be intensively investigated. In this paper, an extremely ductile acrylic adhesive was selected to bond a commonly used unidirectional carbon fibre reinforced polymer with an environmentally friendly biopolymer in a single lap joint. The strength of the joint was characterised under quasi-static and impact loading at −30, +23 and +80°C. It was found that the effect of the strain rate on the maximum failure load increased with temperature. A numerical study was also conducted to predict failure at room temperature. While the quasi-static model predicted accurately the joint behaviour, the impact model overestimated the joint strength as a consequence of the bad adhesion found experimentally.
The appropriateness of the current design specifications for minimum shear reinforcement and maximum nominal shear strength for prestressed concrete members is evaluated through the use of the ...University of Texas' Prestressed Concrete Shear Database (UTPCSDB). Based on experimental evidence, new design provisions for minimum shear reinforcement and maximum nominal shear strength are proposed. PUBLICATION ABSTRACT
Three Gram-staining-negative non-endospore-forming strains were isolated from farmed fish in Chile: one (LM-09-FpT) from a rainbow trout (Oncorhynchus mykiss) and the others (LM-19-FpT and LM-20-Fp) ...from two Atlantic salmon (Salmo salar). Phylogenetic analyses based on 16S rRNA gene sequences indicated that all three isolates belonged to the genus Flavobacterium. In these analyses, strain LM-09-FpT appeared most closely related to the type strains of Flavobacterium chungangense (98.5 % sequence similarity), Flavobacterium glaciei (98.2 %), Flavobacterium aquidurense (97.6 %), Flavobacterium saccharophilum (97.6 %) and Flavobacterium hercynium (97.6 %). The 16S rRNA gene sequences of strains LM-19-FpT and LM-20-Fp were found to be identical and most similar to the corresponding sequences of the type strains of Flavobacterium aquidurense (98.6 %), Flavobacterium frigidimaris (98.5 %), Flavobacterium hercynium (97.9 %), Flavobacterium saccharophilum (97.7 %) and Flavobacterium pectinovorum (97.7 %). For each of the three novel strains, menaquinone (MK-6) was the predominant respiratory quinone and the major compounds in the polar lipid profile were phosphatidylethanolamine, an unidentified aminolipid, phosphatidylserine and two or three unknown lipids. The fatty acid profile of each strain, which comprised major amounts of iso-C15 : 0, C15 : 0 and summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH) as well as smaller amounts of various hydroxylated fatty acids (e.g. iso-C16 : 0 3-OH, iso-C17 : 0 3-OH, C16 : 0 3-OH and C15 : 0 3-OH), indicated that each belonged to the genus Flavobacterium. Based on their physiological and biochemical characteristics and the results of DNA–DNA hybridizations, which showed relatively low levels of relatedness between the novel strains and the most closely related Flavobacterium species, strain LM-09-FpT ( = LMG 26360T = CCM 7940T) represents a novel species within the genus Flavobacterium, for which the name Flavobacterium chilense sp. nov. is proposed, and strains LM-19-FpT ( = LMG 26359T = CCM 7939T) and LM-20-Fp ( = LMG 26331) represent a second novel species within the same genus, for which the name Flavobacterium araucananum sp. nov. is proposed.
This is the first study to isolate, identify and characterize Streptococcus iniae as the causative disease agent in two tilapia (Oreochromis aureus) populations. The populations were geographically ...isolated, of distinct origins, and did not share water sources. Affected fish showed various external (e.g., exophthalmia and cachexia, among others) and internal (e.g., granulomatous septicaemia and interstitial nephritis, among others) signs. All internal organ samples produced pure cultures, two of which (one from each farm, termed S‐1 and S‐2) were subjected to biochemical, PCR and 16S rRNA sequencing (99.5% similarity) analyses, confirming S. iniae identification. The two isolates presented genetic homogeneity regardless of technique (i.e., RAPD, REP‐PCR and ERIC‐PCR analyses). Pathogenic potentials were assessed through intraperitoneal injection challenges in rainbow trout (Oncorhynchus mykiss) and zebrafish (Danio rerio). Rainbow trout mortalities were respectively 40% and 70% at 104 and 106 CFU per fish with the S‐1 isolate, while 100% mortality rates were recorded in zebrafish at 102 and 104 CFU per fish with the S‐2 isolate. The obtained data clearly indicate a relationship between intensified aquaculture activities in Mexico and new disease appearances. Future studies should establish clinical significances for the tilapia industry.
An experimental strategy was developed to obtain mesoporous SiO
2–ZrO
2 and SiO
2–TiO
2 mixed oxides by a sol–gel method, treating the gels hydrothermally. The solids were characterized by nitrogen ...physisorption, pyridine thermodesorption,
29Si nuclear magnetic resonance, SEM and X-ray diffraction. The effects of ZrO
2 content, the generated pressure in the synthesis vessel and further modification of this type of procedure on the solids properties were studied. It was found that SiO
2–ZrO
2 and SiO
2–TiO
2 mixed oxides dried at atmospheric pressure developed type I isotherms. On the other hand, for the SiO
2–ZrO
2 and SiO
2–TiO
2 mixed oxides that were treated under pressure in the autoclave (at high SiO
2 content) the porosity was improved and mesoporous materials exhibiting type IV adsorption isotherms. Specific surface area and pore size distribution were a function of ZrO
2 and TiO
2 content. The materials exhibited narrow pore size distributions with pore diameters in the region of mesopores at about 4
nm and high surface areas, the highest being 481
m
2/g for the 10
wt% ZrO
2 Si–Zr material. Differences in acidity as determined by pyridine thermodesorption were observed to depend on the synthesis parameters and ZrO
2 and TiO
2 concentration.
In this study, we isolated, identified and characterized isolates of Tenacibaculum dicentrarchi in Atlantic salmon (Salmo salar) farmed in Chile for the first time. In 2010 and 2014, mortalities were ...observed in Atlantic salmon (average weight 25–30 and 480–520 g, respectively) at an aquaculture centre in Puerto Montt, Chile. Severe tail rots, frayed fins and, in some cases, damaged gills were detected. Wet smear analyses of these lesions revealed a high occurrence of Gram‐negative, filamentous bacteria. Microbiological analysis of infected gill and tail tissues yielded six bacterial isolates. All were identified as T. dicentrarchi through polyphasic taxonomy, which included phenotypic characterization, 16S rRNA sequencing and multilocus sequence typing. The latter method revealed a close relationship of the Chilean genotype with the T. dicentrarchi type strain and two Norwegian Atlantic cod (Gadus morhua) isolates. The pathogenic potential of the TdChD05 isolate was assessed by challenging Atlantic salmon and rainbow trout (Oncorhynchus mykiss) for one hour, which resulted in mean cumulative mortality rates of 65% and 93%, respectively, as well as clinical signs 14 days post‐challenge. However, challenged Coho salmon (Oncorhynchus kisutch) presented no mortalities or clinical signs of infection. These findings indicate that the geographical and host distribution of T. dicentrarchi is wider than previously established and that this bacterium may have negative impacts on salmonid cultures.
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