What Do Information Frictions Do?

Researchers have incorporated labor or credit market frictions in isolation within simple neoclassical models to open up a role for institutions, inject realism into their models and examine the impact of these distortions on output and employment. We present an overlapping generations model with production in which a labor market friction (moral hazard) coexists with a credit market friction (costly state verification). The simultaneous presence and interaction of these two frictions is studied. Our main results are: (i) while credit market frictions affect real activity and employment both in the short and long run, labor market frictions typically have only short-run effects unless they also affect the volume of investment per worker, (ii) the two frictions amplify each other to produce higher long-run unemployment than would result from only labor market frictions, (iii) these distortions have the ability to prolong the effect of temporary shocks, and (iv) the dynamical properties of economies with both frictions are, somewhat surprisingly, qualitatively similar to their frictionless counterparts.moral hazard; costly state verification; contracts; dynamics; growth models

Spectral Consciousness in Post-9/11 American Poetry

After presenting an overview of scholarship on post-9/11 American poetry, my article focuses on a group of largely neglected post-9/11 poems, which deal with spectral consciousness and hallucinatory experiences. These poems not only challenge a number of traditional binaries like, ‘presence / absence’, ‘living /dead’, ‘synchronic / diachronic’ and so on, but also maintain in their most mature form a certain cognitive stability which lends a rich dimension to post-9/11 poetics. In examining spectral consciousness in such poems, my article also identifies interesting points of connection between postmodernism and them

Natural emergence of neutrino masses and dark matter from RR-symmetry

We propose a supersymmetric extension of the Standard Model (SM) with a continuous global $U(1)_R$ symmetry. The $R$-charges of the SM fields are identified with that of their lepton numbers. As a result, both bilinear and trilinear `$R$-parity violating' (RPV) terms could be present at the superpotential. However, $R$-symmetry is not an exact symmetry as it is broken by supergravity effects. Hence, sneutrinos acquire a small vacuum expectation value in this framework. However, a suitable choice of basis ensures that the bilinear RPV terms can be completely rotated away from the superpotential and the scalar potential. On the other hand, the trilinear terms play a very crucial role in generating neutrino masses and mixing at the tree level. This is noticeably different from the typical $R$-parity violating Minimal Supersymmetric Standard Model. Also, gravitino mass turns out to be the order parameter of $R$-breaking and is directly related to the neutrino mass. We show that such a gravitino, within the mass range $200~\text{keV}\lesssim m_{3/2}\lesssim 0.1~\text{GeV}$ can be an excellent dark matter candidate. Finally, we looked into the collider implications of our framework.Comment: 23 pages, one figure (added), title changed, discussion added on sneutrino vev basis, accepted for publication in JHE

What do information frictions do?

Researchers have incorporated labor or credit market frictions in isolation within simple neoclassical models to open up a role for institutions, inject realism into their models and examine the impact of these distortions on output and employment. We present an overlapping generations model with production in which a labor market friction (moral hazard) coexists with a credit market friction (costly state verification). The simultaneous presence and interaction of these two frictions is studied. Our main results are: (i) while credit market frictions affect real activity and employment both in the short and long run, labor market frictions typically have only short-run effects unless they also affect the volume of investment per worker, (ii) the two frictions amplify each other to produce higher long-run unemployment than would result from only labor market frictions, (iii) these distortions have the ability to prolong the effect of temporary shocks, and (iv) the dynamical properties of economies with both frictions are, somewhat surprisingly, qualitatively similar to their frictionless counterpartsfrictions, contracts, growth

A Comparative Study Between a Micromechanical Cantilever Resonator and MEMS-based Passives for Band-pass Filtering Application

Over the past few years, significant growth has been observed in using MEMS based passive components in the RF microelectronics domain, especially in transceiver components. This is due to some excellent properties of the MEMS devices like low loss, excellent isolation etc. in the microwave frequency domain where the on-chip passives normally tend to become leakier and degrades the transceiver performance. This paper presents a comparative analysis between MEMS-resonator based and MEMS-passives based band-pass filter configurations for RF applications, along with their design, simulation, fabrication and characterization. The filters were designed to have a center frequency of 455 kHz, meant for use as the intermediate frequency (IF) filter in superheterodyne receivers. The filter structures have been fabricated in PolyMUMPs process, a three-polysilicon layer surface micromachining process.Comment: 6 pages, 15 figure

Particle motion around charged black holes in generalized dilaton-axion gravity

The behaviour of massive and massless test particles around asymptotically flat and spherically symmetric, charged black holes in the context of generalized dilaton-axion gravity in four dimensions is studied. All the possible motions are investigated by calculating and plotting the corresponding effective potential for the massless and massive particles as well. Further, the motion of massive (charged or uncharged) test particles in the gravitational field of charged black holes in generalized dilaton-axion gravity for the cases of static and non-static equilibrium is investigated by applying the Hamilton-Jacobi approach.Comment: 11 pages, 5 figures, references added, figure 3 replaced, typos correcte

Engineering of escherichia coli 2-oxoglutarate dehydrogenase complex with mechanistic and synthetic goals

The Escherichia coli 2-oxoglutarate dehydrogenase complex (OGDHc) compromises multiple copies of three enzymes - 2-oxoglutarate dehydrogenase (E1o), dihydrolipoyl succinyltransferase (E2o), and dihydrolipoyl dehydrogenase (E3). OGDHc is found in the Krebs cycle and catalyzes the formation of the all-important succinyl-Coenzyme A (succinyl-CoA). OGDHc was engineered to understand the catalytic mechanism and optimized for chemical synthetic goals. Succinyl-CoA formation takes place within the catalytic domain of E2o via a transesterification reaction. The succinyl group from the thiol ester of S8-succinyldihydrolipoyl-E2o is transferred to the thiol group of CoA. Mechanistic studies were designed to investigate enzymatic transthioesterification. His375 and Asp374 was shown to be important in E2o. The magnitude of the rate acceleration provided by these residues suggests a role in stabilization of the symmetrical tetrahedral oxyanionic intermediate by formation of two hydrogen bonds, rather than in acid–base catalysis. Further evidence ruling out a role in acid–base catalysis is provided by saturation mutagenesis studies at His375 and substitutions to other potential hydrogen bond participants at Asp374. The rate constant for reductive succinylation of the E2o lipoyl domain (LDo) by E1o and 2-oxoglutarate (99 s-1) was approximately twofold larger than the rate constant for kcat (48 s-1) for the overall reaction (NADH production). It could be concluded that succinyl transfer to CoA and release of succinyl-CoA is the rate-limiting step. The results suggest a revised mechanism of catalysis for acyl transfer in the superfamily of 2-oxo acid dehydrogenase complexes, thus provide fundamental information regarding acyl-CoA formation, so important for several biological processes including post-translational succinylation of protein lysines. OGDHc was converted from a 2-oxoglutarate dehydrogenase to a 2-oxo aliphatic dehydrogenase complex by engineering consecutive components. OGDHc was reprogrammed to accept alternative substrates by evolving the E1o and E2o components. Wt-ODGHc does not accept aliphatic substrates. E1o was previously engineered to accept a non-natural aliphatic substrate, 2-oxovalerate (2-OV). E2o also required engineering to accept 2-OV in the overall reaction. Hence, saturation mutagenesis libraries of E2o were screened and several variants were identified for 2-OV activity. Variants also displayed activity for larger aliphatic substrates, which demonstrates the potential green synthetic utility

Contraception and the Demographic Transition

Inspired by the historical English experience, we modify the Beckerian paradigm of fertility by incorporating costly, societal influence on contraception. Heterogeneous, generationally-linked households choose between ‘traditional’ and ‘modern’ contraception. The modern has a higher fixed but lower variable cost of averting childbirths. Initially the rich adopt the modern, which unleashes society-wide diffusion. Eventually everyone switches, lowering fertility further and across households. Hastening the switch is falling child mortality. Quantitative experiments suggest contraception was a vital link between the historical mortality and fertility transitions, though not the latter’s proximate cause. Implications for more recent transitions are discussed