Effect of Student Loans on Income Inequality in the United States

Student loan is a pervasive problem in the United States. Historically, higher education has been a major driver of intergenerational mobility in the United States. The current student loan has increased substantially over the years, surpassing credit card and auto loans. Using panel data from all States, this paper attempts to empirically predict if income inequality is affected by student loans. Statistical analysis points towards student loan exacerbating income inequality. Other variables such as private college tuition and household poverty have a highly significant negative effect on income inequality. The overall results suggest that increased access to higher education at the expense of higher student loans may be countervailing to the income distribution dynamics of the United States

Nonlocal thermoelastic vibrations for variable thermal conductivity nanobeams due to harmonically varying heat

This article constructs a new model of nonlocal thermoelasticity beam theory with phase-lags considering the thermal conductivity to be variable. A nanobeam subjected to a harmonically varying heat is considered. The nonlocal theories of coupled thermoelasticity and generalized thermoelasticity with one relaxation time can be extracted as limited and special cases of the present model. The effects of the variable thermal conductivity parameter, the nonlocal parameter, the phase-lags and the angular frequency of thermal vibration on the lateral vibration, the temperature, the displacement, and the bending moment of the nanobeam are investigated

Pyrrolizine-5-carboxamides: Exploring the impact of various substituents on the anti-inflammatory and anticancer activities

Towards optimization of the pyrrolizine-5-carboxamide scaffold, a novel series of six derivatives (4a-c and 5a-c) was prepared and evaluated for their anti-inflammatory, analgesic and anticancer activities. The (EZ)-7-cyano-6-((4-hydroxybenzylidene)amino)-N-(p-tolyl)-2,3-dihydro-1H-pyrrolizine-5-carboxamide (4b) and (EZ)-6-((4-chlorobenzylidene)-amino)-7-cyano-N-(p-tolyl)-2,3-dihydro-1H-pyrrolizine-5-carboxamide (5b) bearing the electron donating methyl group showed the highest anti-inflammatory activity while (EZ)-6-((4-chlorobenzylidene)amino)-7-cyano-N-phenyl-2,3-dihydro-1H-pyrrolizine-5-carboxamide (5a) was the most active analgesic agent. Cytotoxicity of the new compounds was evaluated against the MCF-7, A2780 and HT29 cancer cell lines using the MTT assay. Compounds 4b and 5b displayed high anticancer activity with IC50 in the range of 0.30–0.92 µmol L–1 against the three cell lines, while compound (EZ)-N-(4-chlorophenyl)-7-cyano-6-((4-hydroxybenzylidene)-amino)-2,3-dihydro-1H-pyrrolizine-5-carboxamide (4c) was the most active against MCF-7 cells (IC50 = 0.08 µmol L–1). Both the anti-inflammatory and anticancer activities of the new compounds were dependent on the type of substituent on the phenyl rings. Substituents with opposite electronic effects on the two phenyl rings are preferable for high cytotoxicity against the MCF-7 and A2780 cells. COX inhibition was suggested as the molecular mechanism of the anti-inflammatory activity of the new compounds while no clear relationship could be observed between COX inhibition and anticancer activity. Compound 5b, the most active against the three cell lines, induced dose-dependent early apoptosis with 0.1–0.2 % necrosis in MCF-7 cells. New compounds showed promising drug-likeness scores while the docking study revealed high binding affinity to COX-2. Taken together, this study highlighted the significant impact of the substituents on the anti-inflammatory and anticancer activity of pyrrolizine-5-carboxamides, which could help in further optimization to discover good leads for the treatment of cancer and inflammation

NDM-524: CASE STUDY TO ASSESS THE SENSITIVITY OF PRESTRESSED CONCRETE POLES TO TORNADOES

Transmission line structures play a vital role in transmitting electricity from the source of production to the distribution system. The main components of a transmission line are the conductors, the insulator strings, the ground wires and the supporting towers. Among the different types of supporting towers, prestressed concrete transmission poles have the advantages of low installation and maintenance costs, appropriate delivery time, and corrosion resistivity. To the best of the authors’ knowledge, this paper represents the first investigation conducted to assess the response of cantilever prestressed concrete poles to tornadoes. The localized nature of the tornadoes and the extended length of the conductors introduce some challenges in predicting the critical response of power transmission towers to tornadoes. The current study is conducted numerically using an in-house numerical model that includes the following: (1) a three-dimensional tornado wind field developed using computational fluid dynamics simulations; (2) a non-linear simulation of the structural behaviour of a prestressed concrete transmission poles taking into account the non-linear behaviour of the concrete and of the prestressed strands, and (3) a simulation of the non-linear behaviour of the conductors including the effects of the pretension force, sagging, the insulator’s stiffness and the non-uniform distribution of wind loads. Details of this numerical model are briefly discussed in this paper. A case study is considered to assess the importance of including the effect of tornadoes in the design of prestressed concrete poles

Deadly heat wave in Karachi, July 2015: Negligence or mismanagement?

[No abstract available