Junior Must Pay: Pricing the Implicit Put in Privatizing Social Security

Proposals that portion of the Social Security Trust Fund assets be invested in equities entail the possibility that a severe decline in equity prices renders the Fund assets insufficient to provide the currently mandated level of benefits. In this event, existing taxpayers may be compelled to act as insurers of last resort. The cost to taxpayers of such an implicit commitment equals the value of a put option with payoff equal to the benefit's shortfall. We calibrate an OLG model that generates realistic equity premia and value the put. With 20 percent of the Fund assets invested in equities, the highest level currently under serious discussion, we value a put that guarantees the currently mandated level of benefits at one percent of GDP, or a temporary increase in Social Security taxation of at most 25 percent. We value a put that guarantees 90 percent of benefits at merely .03 percent of GDP. In contrast to earlier literature, our results account for the significant changes in the distribution of security returns resulting from Trust Fund purchases. We also explore the inter-generational welfare implications of the guarantee.

Junior is Rich: Bequests as Consumption

We explore the consequences for asset pricing of admitting a bequest motive into an otherwise standard overlapping generations model where agents trade equity and perpetual debt securities. Prices of securities are seen to be approximately 50% higher in an economy with bequests as compared to an otherwise identical one where bequests are absent. Robust estimates of the equity premium are obtained in several cases where the desire to leave bequests is modest relative to the desire for old age consumption.

Short SULF1/SULF2 splice variants predominate in mammary tumours with a potential to facilitate receptor tyrosine kinase-mediated cell signalling

The relative roles of SULF1 and SULF2 enzymes in tumour growth are controversial, but short SULF1/SULF2 splice variants predominate in human mammary tumours despite their non-detectable levels in normal mammary tissue. Compared with the normal, the level of receptor tyrosine kinase (RTK) activity was markedly increased in triple-positive mammary tumours during later stages of tumour progression showing increased p-EGFR, p-FGFR1 and p-cMet activity in triple-positive but not in triple-negative tumours. The abundance of catalytically inactive short SULF1/SULF2 variants permits high levels of HS sulphation and thus growth driving RTK cell signalling in primary mammary tumours. Also observed in this study, however, was increased N-sulphation detected by antibody 10E4 indicating that not only 6-O sulphation but also N-sulphation may contribute to increased RTK cell signalling in mammary tumours. The levels of such increases in not only SULF1/SULF2 but also in pEGFR, pFGFR1, p-cMet and Smad1/5/8 signalling were further enhanced following lymph node metastasis. The over-expression of Sulf1 and Sulf2 variants in mammary tumour-derived MDA-MB231 and MCF7 cell lines by transfection further confirms Sulf1-/Sulf2-mediated differential modulation of growth. The short variants of both Sulf1 and Sulf2 promoted FGF2-induced MDA-MB231 and MCF7 in vitro growth while full-length Sulf1 inhibited growth supporting in vivo mammary tumour cell signalling patterns of growth. Since a number of mammary tumours become drug resistant to hormonal therapy, Sulf1/Sulf2 inhibition could be an alternative therapeutic approach to target such tumours by down-regulating RTK-mediated cell signalling

A simple sandpile model of active-absorbing state transitions

We study a simple sandpile model of active-absorbing state transitions in which a particle can hop out of a site only if the number of particles at that site is above a certain threshold. We show that the active phase has product measure whereas nontrivial correlations are found numerically in the absorbing phase. It is argued that the system relaxes to the latter phase slower than exponentially. The critical behavior of this model is found to be different from that of the other known universality classes.Comment: Revised version. To appear in Phys. Rev.

Evanescent character of the repulsive thermal Casimir force

The physical origin of the negative thermal correction to the Casimir force between metals is clarified. For this purpose the asymptotic behavior of the thermal Casimir force is analyzed at large and small distances in the real frequency representation. Contributions from propagating and evanescent waves are considered separately. At large distances they cancel each other in substantial degree so that only the attractive Lifshitz limit survives. At smaller separations the repulsive evanescent contribution of s-polarization dominates in the case of two metals or a metal and a high-permittivity dielectric. Common origin and order of magnitude of the repulsion in these two cases demonstrate naturalness of the controversial large thermal correction between metals.Comment: to be published in Phys. Rev.

Qualitative lens to assessing the ground level implementation of conditional cash transfer scheme in India

Background: Conditional cash transfer scheme, known as Janani Suraksha Yojna (JSY) is an innovative concept on the lines of behavioral economics. The study aimed to investigate factors associated with effective implementation of scheme at the community in Delhi, India.Methods: We did qualitative study to investigate the implementation factors related to JSY by conducting in depth interviews with 50 mothers in a span of three months. All the interviews were conducted in local language (Hindi) by the principle investigator. The data were collected through semi-structured interviews, which were later transcribed and recorded in Microsoft-Excel sheet. The themes were developed inductively, meaning that they were anticipated from the design of interview, during literature review and deductively meaning that they were not anticipated during design of the interview.Results: The mean (±SD) age of the women was 25(±3.5) years. More than three-forth of the mothers were not aware of the JSY scheme. Most of the women claimed limited support from accredited social health activist at the time of delivery. Provision of respectful maternity care was poor with women reporting episodes of verbal abuses, and arrogant attitude of the staff. Issues in utilization of the scheme encountered in study were untimely disbursement of money, problems in the process of BPL cards formation, lack of awareness on the scheme, banking illiteracy etc.Conclusions: Amidst the wider geographic reach and accessibility of the scheme by the poor, there exists some barriers to its effective implementation and practical challenges, which need immediate addressal by program managers

Menstrual hygiene practices among adolescent girls in a resettlement colony of Delhi: a cross-sectional study

Background: Menarche is an important milestone in the life of a girl which signifies the onset of fertility in a woman. To understand the health consequences and importance of menstrual hygiene practices among adolescent girls, it is important to study the current practices about the same so that future interventions can be planned accordingly.Methods: This study adopted a cross-sectional study design. A total of 85 adolescent girls (10-19 years old) were interviewed by the investigator over a period of 3 months (Jan-Mar 2015). Data were analyzed using the software SPSS version 17.Results: Out of 85 adolescent girls studied, the majority was between 15 to 19 years. In our study 71(83.5%) out of 85 adolescent girls had already started their menstruation. The mean (±SD) age of menarche in the study subjects was 11.4±5.3 years. Around 33 out of 71 (46.4%) girls practiced different restrictions during menstruation. Out of 71 (85.9%) girls used sanitary pads during menstruation. In cases of reused cloth, the place of its drying was observed, responses stated were; outside the house in sunlight in 1 (5.8%) girl, 14 (82.2%) dried them inside the house, and 2 (11.7%) girls dried them outside in a dark place.Conclusions: It is imperative to strengthen the menstrual hygiene management (MHM) programs of the country and have a greater outreach. Multiple strategies need to be used to address this such as education on reproductive health and menstruation provided in schools, media campaign’s and improving water and sanitation for improving school retention of adolescent girls and their overall health

TCAD Simulations and Small Signal Modeling of DMG AlGaN/GaN HFET

This article presents extraction of small signal model parameters and TCAD simulation of novel asymmetric field plated dual material gate AlGaN/GaN HFET first time. Small signal model is essential for design of LNA and microwave electronic circuit by using the proposed superior performance HFET structure. Superior performances of device are due to its dual material gate structure and field plate that can provide better electric field uniformity, suppression of short channel effects and improvement in carrier transport efficiency. In this article we used direct parameter extraction methodology in which S-parameters of device were measured using pinchoff cold FET biasing. The measured S-parameters are then transformed into Y-parameters to extract capacitive elements and then in to Z-parameters to extract series parasitic elements. Intrinsic parameters are extracted from Y-parameters after de-embedding all parasitic elements of devce. Microwave figure of merits and dc performance are also studied for proposed HFET. The important figure of merits of device reported in the paper include transconductance, drain conductance, current gain, transducer power gain, available power gain, maximum stable gain, maximum frequency of oscillation, cut-off frequency, stability factor and time delay. Reported results are validated with experimental and simulation results for consistency and accuracy