ANSYS 10.0, a finite element software, has been used to simulate simply supported RC beams consisting of circular openings with varying diameters in 3-D nonlinear finite element method. The RC beam model is created using SOLID65, SOLID45 and LINK8 elements representing both linear and non-linear behavior of concrete, steel plate and reinforcing bar respectively. The inherent assumption is that there is full displacement compatibility between the reinforcement and the concrete and no bond slippage occurs. The FE beam model is verified against experimental test data of RC solid beam without opening available in literature and then a number of verified models of simply supported RC beams with circular opening are loaded monotonically with two incremental concentrated loads. A model with equivalent square opening of 133 mm in width is also analyzed. An attempt is made to know the effects of circular opening size on the behavior of RC beams from load-deflection curve, crack pattern and stress distribution. RC rectangular beams with circular openings of diameter less than 44% of the depth of beam (D) has no effect on the ultimate load capacity but circular openings with diameter more than 44% of D reduces the ultimate load capacity at least 34.29%.

Alzheimer's disease (AD) is still an incurable neurodegenerative disease that causes dementia. AD changes the brain function that, over time, impairs memory and diminishes judgment and reasoning ability. Pathophysiology of AD is complex. Till now the cause of AD remains unknown, but risk factors include family history and genetic predisposition. The drugs previously approved for AD treatment do not modify the disease process and only provide symptomatic improvement. Over the past few decades, research has led to significant progress in the understanding of the disease, leading to several novel strategies that may modify the disease process. One of the major developments in this direction is the amyloid β (Aβ) aggregation. Small molecules could block the initial stages of Aβ aggregation, which could be the starting point for the design and development of new AD drugs in the near future. In this review we summarize the most promising small-molecule Aβ-aggregation inhibitors including natural compounds, novel small molecules, and also those are in clinical trials. Moreover, we briefly summarized some reported docking studies of small-molecule Aβ aggregation inhibitors. These will give us an idea about the chemical features required to design novel small molecules with anti-Aβ aggregation properties.

Many existing reinforced concrete buildings in developing countries located in seismic areas do not possess sufficient strength and ductility characteristics to resist the effects of severe earthquakes. Among other deficiencies, improper detailing of reinforcement and poor quality of materials are major causes of poor seismic performance. More specifically, inadequate lap splice lengths provided at floor levels on plain column longitudinal bars, particularly when concrete strength is low, is a widespread deficiency that has not been investigated in detail to date. Information on the behavior of such columns under earthquake actions is extremely important for reliable assessment of the seismic safety of many existing structures with detailing deficiencies and poor construction quality. In this study, the effect of lap splice length on the cyclic lateral load behavior of low-strength RC columns with plain longitudinal bars (14 mm diameter) was investigated experimentally. The specimens were designed to represent columns with low axial loads. The geometric ratio of the longitudinal reinforcement and the volumetric ratio of the lateral reinforcement of the columns are 1% and 0.8%, respectively. The test program included five RC columns with lap splice lengths of 25, 35, 44 and 55 times longitudinal bar diameter, as well as a reference specimen with continuous longitudinal bars. Test results clearly demonstrated that presence of 180-degree hooks at the ends of the lap splice reduces the negative influence of the inadequate lap splice length on RC member performance, even in the case of low-strength concrete. All specimens reached their flexural strengths and did not experience considerable strength degradation until large drift levels. Test observations were supported with findings of a fiber-based analytical model, which also demonstrated the influence of hooks on improving the bond slip behavior along inadequate lap splices.

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A simple, sensitive and precise reversed phase high performance liquid chromatographic (RP-HPLC) method has been developed for the estimation of naproxen in pharmaceutical dosage forms. The method was developed using the mobile phase comprising of dibasic sodium phosphate buffer (Na 2 HPO 4 ) at pH 7.80 (adjusted by sodium hydroxide) and acetonitrile in the ratio of 70:30 (v/v) over C-18 column (250 x 4.6 mm, 5µm, Phenomenex Inc.) at ambient temperature. The flow rate was at 0.7 ml/min and the column washing was monitored by UV detector at 225 nm. The retention time of naproxen was 4.8 ± 0.1 min. The recovery was found to be >97% which is demonstrative of accuracy of the protocol. Inter-day and intra-day precision of the newly developed method were less than the maximum allowable limit (RSD% ≤ 2.0) according to ICH, USP and FDA guidelines. The method showed linear response with correlation coefficient (r 2 ) value of 0.9991. Therefore, the method was found to be accurate, reproducible, sensitive and less time consuming and can be successfully applied for routine analysis of naproxen in pharmaceutical formulations.