Effect of Different grades of River sand Cement and Copper Slag Cement Matrices on Flexural Behaviourof Ferrocement Slabs

Ferrocement is a versatile construction material having light weight, closely spaced small diameter reinforcement covered with cement mortar. Lot of works have been carried out onferrocement by using  river sand as fine aggregate in India and other countries. Research also has been carried out on ferrocement with other than cement mortar. Matrices like polymer impregnated cement mortar, resin mortar, latex modified cement mortar and fibre reinforced mortar matrix and studied their structural responses at CSIR-Structural Engineering Research Centre, Chennai and Nihon University, Japan. Research works on ferrocement is under progress by using copper slag as fine aggregate in cement mortar at Easwari Engineering College, Ramapuram, Chennai. Totally six mortar mixtures, three with river sand and three with copper slag as fine aggregate and three different strength in each were used as matrix in preparation of ferrocement slabs. Reinforcement content was same in all specimens. Mechanical properties, Viz., compressive strength, split tensile strength and flexural strength were evaluated for all the mixtures.To evaluate the effect of different mortar proportions and different types of fine aggregates on flexural behaviour of ferrocement slabs having same size and reinforcement content. The types of fine aggregate used are normal river sand and the same gradation of copper slag. Different mortar mixtures used are 1:1, 1:2 and 1:3 (Cement: Fine Aggregate) and equal volume to river sand of copper slag was used in another three mixtures. Totally 6 mortar mixtures were used and studied their mechanical properties, viz., compressive strength, split tensile strength and flexural strength

Utilisation of flyash as cement replacement material to produce high performance concrete

Disposal of fly ash, a waste product from thermal power plants, is a major problem in India.Many R&D and academic institutions are actively involved in the effective utilisation of flyash in Civil Engineering applications. The Structural Engineering Research Centre (SERC),Chennai has carried out extensive research on utilisation of fly ash in concrete as partial cement replacement material (CRM) since 1975 . Recently, SERC has carried out extensive R&D work on development of High Performance Concrete (HPC) mixes using flyash(FA),ground granulated blast furnace slag(GGBS) and silica fume(SF) as mineral dmixtures,especially to improve the durability characteristics of cement concrete. This paper presents the mechanical and urability properties of different HPC mixes containing fly ash. HPCs using flyash as mineral admixture have been used to evelop precast concrete products such as, non-pressure pipes and heavy duty paver blocks and these developments are eported in this paper

STRESS STRAIN BEHAVIOUR OF ULTRA HIGH PERFORMANCE CONCRETE UNDER UNIAXIAL COMPRESSION

ABSTRACT Ultra High Performance Concrete (UHPC), which is a type of improved high strength concrete, is a recent development in concrete technology. The stress-strain behaviour of UHPC under compression is of considerable interest in the design of UHPC members because the material is intrinsically strong in compression, and accurate prediction of their structural behaviour. An attempt has been made in the present study to determine the complete stress-strain curves from uniaxial compression tests and to develop stress-strain models representing this behaviour. The effect of material composition on the stress-strain behaviour and the consequent variation in the model parameters and the compression toughness are presented in the paper. The highest cylinder compressive strength of 171.3 MPa and elastic modulus of 44.8 GPa were recorded for 2% 13 mm fibers. The optimum fiber content was found to be 3% of 6mm or 2% of 13mm. A new measure of compression toughness known as MTI (modified toughness index) is proposed and it is found to range from 2.64 to 4.65 for UHPC mixes. It appears to be a better measure of the reinforcing action of fibers and their crack bridging action than some of the earlier measures proposed by other investigators. For modelling of the complete stress-strain curve, several stress-strain behavioural models were examined and a modification of model adopted by earlier by Voo et al [2003] was found to provide the best fit for all the mixes and provided very good agreement with the experimental results

Hormetic UV-C seed treatments for the control of tomato diseases

© 2019 British Society for Plant Pathology Hormesis is a dose response phenomenon in which low, non-damaging doses of a stressor bring about a positive response in the organism undergoing treatment. Evidence is provided here that hormetic UV-C treatments of tomato seed can control disease caused by Botrytis cinerea, Fusarium oxysporum f. sp. lycopersici (FOL) and f. sp. radicis-lycopersici (FORL) on tomato (Solanum lycopersicum). Treating seeds with a 4kJm−2 dose of UV-C significantly reduced both the disease incidence and progression of B.cinerea, with approximately 10% reductions in both on cv. Shirley. Disease severity assays for FOL and FORL on cv. Moneymaker showed dose-dependent responses: UV-C treatments of 4 and 6kJm−2 significantly reduced the disease severity scores of FOL, whilst only the 6kJm−2 showed significant reductions for FORL. To determine the effects of treatment on germination and seedling growth, UV-C doses of 4, 8 and 12kJm−2 were performed on cv. Shirley. No negative impacts on germination or seedling growth were observed for any of the treatments. However, the 8kJm−2 treatment showed significant biostimulation, with increases in seedling, root and hypocotyl dry weight of 11.4%, 23.1% and 12.0%, respectively, when compared to the control. Furthermore, significant increases in the root-mass fraction (10.6%) and root:shoot ratio (13.1%) along with a decrease in shoot-mass fraction (2.0%) indicates that the 8kJm−2 treatment stimulated root growth to the greatest extent. There was no effect on hypocotyl and primary root length or the number of lateral roots, indicating no adverse effects to basic root architecture or seedling growth

Design, Synthesis, and Evaluation of Hydroxamic Acid-Based Molecular Probes for In Vivo Imaging of Histone Deacetylase (HDAC) in Brain

Hydroxamic acid-based histone deacetylase inhibitors (HDACis) are a class of molecules with therapeutic potential currently reflected in the use of suberoylanilide hydroxamic acid (SAHA; Vorinostat) to treat cutaneous T-cell lymphomas (CTCL). HDACis may have utility beyond cancer therapy, as preclinical studies have ascribed HDAC inhibition as beneficial in areas such as heart disease, diabetes, depression, neurodegeneration, and other disorders of the central nervous system (CNS). However, little is known about the pharmacokinetics (PK) of hydroxamates, particularly with respect to CNS-penetration, distribution, and retention. To explore the rodent and non-human primate (NHP) brain permeability of hydroxamic acid-based HDAC inhibitors using positron emission tomography (PET), we modified the structures of belinostat (PXD101) and panobinostat (LBH-589) to incorporate carbon-11. We also labeled PCI 34051 through carbon isotope substitution. After characterizing the in vitro affinity and efficacy of these compounds across nine recombinant HDAC isoforms spanning Class I and Class II family members, we determined the brain uptake of each inhibitor. Each labeled compound has low uptake in brain tissue when administered intravenously to rodents and NHPs. In rodent studies, we observed that brain accumulation of the radiotracers were unaffected by the pre-administration of unlabeled inhibitors. Knowing that CNS-penetration may be desirable for both imaging applications and therapy, we explored whether a liquid chromatography, tandem mass spectrometry (LC-MS-MS) method to predict brain penetrance would be an appropriate method to pre-screen compounds (hydroxamic acid-based HDACi) prior to PET radiolabeling. LC-MS-MS data were indeed useful in identifying additional lead molecules to explore as PET imaging agents to visualize HDAC enzymes in vivo. However, HDACi brain penetrance predicted by LC-MS-MS did not strongly correlate with PET imaging results. This underscores the importance of in vivo PET imaging tools in characterizing putative CNS drug lead compounds and the continued need to discover effect PET tracers for neuroepigenetic imaging.Chemistry and Chemical Biolog

Original Article Design, synthesis, and evaluation of hydroxamic acid-based molecular probes for in vivo imaging of histone deacetylase (HDAC) in brain

Abstract: Hydroxamic acid-based histone deacetylase inhibitors (HDACis) are a class of molecules with therapeutic potential currently reflected in the use of suberoylanilide hydroxamic acid (SAHA; Vorinostat) to treat cutaneous T-cell lymphomas (CTCL). HDACis may have utility beyond cancer therapy, as preclinical studies have ascribed HDAC inhibition as beneficial in areas such as heart disease, diabetes, depression, neurodegeneration, and other disorders of the central nervous system (CNS). However, little is known about the pharmacokinetics (PK) of hydroxamates, particularly with respect to CNS-penetration, distribution, and retention. To explore the rodent and non-human primate (NHP) brain permeability of hydroxamic acid-based HDAC inhibitors using positron emission tomography (PET), we modified the structures of belinostat (PXD101) and panobinostat (LBH-589) to incorporate carbon-11. We also labeled PCI 34051 through carbon isotope substitution. After characterizing the in vitro affinity and efficacy of these compounds across nine recombinant HDAC isoforms spanning Class I and Class II family members, we determined the brain uptake of each inhibitor. Each labeled compound has low uptake in brain tissue when administered intravenously to rodents and NHPs. In rodent studies, we observed that brain accumulation of the radiotracers were unaffected by the pre-administration of unlabeled inhibitors. Knowing that CNS-penetration may be desirable for both imaging applications and therapy, we explored whether a liquid chromatography, tandem mass spectrometry (LC-MS-MS) method to predict brain penetrance would be an appropriate method to pre-screen compounds (hydroxamic acid-based HDACi) prior to PET radiolabeling. LC-MS-MS data were indeed useful in identifying additional lead molecules to explore as PET imaging agents to visualize HDAC enzymes in vivo. However, HDACi brain penetrance predicted by LC-MS-MS did not strongly correlate with PET imaging results. This underscores the importance of in vivo PET imaging tools in characterizing putative CNS drug lead compounds and the continued need to discover effect PET tracers for neuroepigenetic imaging

Highly Diastereo- and Enantioselective CuH-Catalyzed Synthesis of 2,3-Disubstituted Indolines

A diastereo- and enantioselective CuH-catalyzed method for the preparation of highly functionalized indolines is reported. The mild reaction conditions and high degree of functional group compatibility as demonstrated with substrates bearing heterocycles, olefins, and substituted aromatic groups, renders this technique highly valuable for the synthesis of a variety of cis-2,3-disubstituted indolines in high yield and enantioeselectivity.National Institutes of Health (U.S.) (Award GM46059)Danish Council for Independent Research (Postdoctoral Fellowship

Flexural Behaviour Of Strengthened RC Beams With Multi-Directional Basalt Fibre - Reinforced Polymer Composites

The paper describes an experimental behaviour of the basalt fibre reinforced polymer composite by external strengthening to the concrete beams. The BFRP composite is wrapped at the bottom face of R.C beam as one layer, two layers, three layers and four layers. The different characteristics - are studied in - first crack load, ultimate load, tensile and compressive strain, cracks propagation, crack spacing and number of cracks etc. To - investigate, total of five beams size 100mm× 160mm×1700mm were cast. One beam is taken as control and others are strengthened with BFRP composite with layers. From this investigation, the first crack load is increased depending on the increment in layers from 6.79% to 47.98%. Similarly, the ultimate load carrying - capacity is increased from 5.66% to 20%. The crack’s spacing is also reduced with an increase in the number of layer