The Impact of Welfare Reform on Leaver Characteristics, Employment and Recidivism

Welfare reform has transformed the U.S. cash assistance program for single parents and their children. Although there remains substantial uncertainty about the importance of reform in producing the subsequent decline in the welfare caseload, even less is known about its impact on the experiences and well being of former welfare recipients. The analysis here focuses on the characteristics and employment of welfare recipients in the state of Missouri over the period 1990-1999. We find that there has been little change in the observable characteristics of those entering, on, or leaving welfare, but there has been a dramatic growth in the importance of employment for all these groups. We also examine the dynamics of employment and welfare recidivism comparing cohorts of leavers prior to and after welfare reform. We find that after welfare reform leavers are much more likely to be working, have higher total earnings, work for employers with similar characteristics, and are less likely to return to welfare. These results suggest that welfare reform has not materially harmed welfare recipients.

The Impact of Welfare Reform on Leaver Characteristics, Employment and Recidivism

Welfare reform has transformed the U.S. cash assistance program for single parents and their children. Although there remains substantial uncertainty about the importance of reform in producing the subsequent decline in the welfare caseload, even less is known about its impact on the experiences and well being of former welfare recipients. The analysis here focuses on the characteristics and employment of welfare recipients in the state of Missouri over the period 1990-1999. We find that there has been little change in the observable characteristics of those entering, on, or leaving welfare, but there has been a dramatic growth in the importance of employment for all these groups. We also examine the dynamics of employment and welfare recidivism comparing cohorts of leavers prior to and after welfare reform. We find that after welfare reform leavers are much more likely to be working, have higher total earnings, work for employers with similar characteristics, and are less likely to return to welfare. These results suggest that welfare reform has not materially harmed welfare recipients

The Impact of Welfare Reform on Leaver Characteristics, Employment and Recidivism

Welfare reform has transformed the U.S. cash assistance program for single parents and their children. Although there remains substantial uncertainty about the importance of reform in producing the subsequent decline in the welfare caseload, even less is known about its impact on the experiences and well being of former welfare recipients. The analysis here focuses on the characteristics and employment of welfare recipients in the state of Missouri over the period 1990-1999. We find that there has been little change in the observable characteristics of those entering, on, or leaving welfare, but there has been a dramatic growth in the importance of employment for all these groups. We also examine the dynamics of employment and welfare recidivism comparing cohorts of leavers prior to and after welfare reform. We find that after welfare reform leavers are much more likely to be working, have higher total earnings, work for employers with similar characteristics, and are less likely to return to welfare. These results suggest that welfare reform has not materially harmed welfare recipients

Selective inhibitors of trypanosomal uridylyl transferase RET1 establish druggability of RNA post-transcriptional modifications.

Non-coding RNAs are crucial regulators for a vast array of cellular processes and have been implicated in human disease. These biological processes represent a hitherto untapped resource in our fight against disease. In this work we identify small molecule inhibitors of a non-coding RNA uridylylation pathway. The TUTase family of enzymes is important for modulating non-coding RNA pathways in both human cancer and pathogen systems. We demonstrate that this new class of drug target can be accessed with traditional drug discovery techniques. Using the Trypanosoma brucei TUTase, RET1, we identify TUTase inhibitors and lay the groundwork for the use of this new target class as a therapeutic opportunity for the under-served disease area of African Trypanosomiasis. In a broader sense this work demonstrates the therapeutic potential for targeting RNA post-transcriptional modifications with small molecules in human disease.This work was supported by two grants from the European Research Council (RG58558, RG67639) and a grant from Cancer Research UK (RG51661) to E.A.MThis is the author accepted manuscript. The final version is available from [publisher] via http://dx.doi.org/10.1080/15476286.2015.113742

Mid-infrared InAs/InAsSb superlattice nBn photodetector monolithically integrated onto silicon

Mid-infrared (MIR) silicon photonics holds the potential for realizing next generation ultracompact spectroscopic systems for applications in gas sensing, defense, and medical diagnostics. The direct epitaxial growth of antimonide-based compound semiconductors on silicon provides a promising approach for extending the wavelength of silicon photonics to the longer infrared range. This paper reports on the fabrication of a high performance MIR photodetector directly grown onto silicon by molecular beam epitaxy. The device exhibited an extended cutoff wavelength at ∼5.5 μm and a dark current density of 1.4 × 10–2 A/cm2 under 100 mV reverse bias at 200 K. A responsivity of 0.88 A/W and a specific detectivity in the order of 1.5 × 1010 Jones was measured at 200 K under 100 mV reverse bias operation. These results were achieved through the development of an innovative structure which incorporates a type-II InAs/InAsSb superlattice-based barrier nBn photodetector grown on a GaSb-on-silicon buffer layer. The difficulties in growing GaSb directly on silicon were overcome using a novel growth procedure consisting of an efficient AlSb interfacial misfit array, a two-step growth temperature procedure and dislocation filters resulting in a low defect density, antiphase domain free GaSb epitaxial layer on silicon. This work demonstrates that complex superlattice-based MIR photodetectors can be directly integrated onto a Si platform, which provides a pathway toward the realization of new, high performance, large area focal plane arrays and mid-infrared integrated photonic circuits

Influence of a Bi surfactant on Sb incorporation in InAsSb alloys

The influence of using a Bi surfactant during the growth of InAsSb on the composition was examined, and it was found that increasing Bi flux on the surface during growth inhibits the incorporation of Sb. Analysis of the data via a kinetic model of anion incorporation shows that surface Bi acts as a catalyst for InAs formation, thus inhibiting Sb incorporation

Effect of a Single Amino Acid Change in MHC Class I Molecules on the Rate of Progression to AIDS

Background From studies of genetic polymorphisms and the rate of progression from human immunodeficiency virus type 1 (HIV-1) infection to the acquired immunodeficiency syndrome (AIDS), it appears that the strongest susceptibility is conferred by the major-histocompatibility-complex (MHC) class I type HLA-B*35,Cw*04 allele. However, cytotoxic T-lymphocyte responses have been observed against HIV-1 epitopes presented by HLA-B*3501, the most common HLA-B*35 subtype. We examined subtypes of HLA-B*35 in five cohorts and analyzed the relation of structural differences between HLA-B*35 subtypes to the risk of progression to AIDS. Methods Genotyping of HLA class I loci was performed for 850 patients who seroconverted and had known dates of HIV-1 infection. Survival analyses with respect to the rate of progression to AIDS were performed to identify the effects of closely related HLAB* 35 subtypes with different peptide-binding specificities. Results HLA-B*35 subtypes were divided into two groups according to peptide-binding specificity: the HLA-B*35-PY group, which consists primarily of HLAB* 3501 and binds epitopes with proline in position 2 and tyrosine in position 9; and the more broadly reactive HLA-B*35-Px group, which also binds epitopes with proline in position 2 but can bind several different amino acids (not including tyrosine) in position 9. The influence of HLA-B*35 in accelerating progression to AIDS was completely attributable to HLAB* 35-Px alleles, some of which differ from HLA-B*35- PY alleles by only one amino acid residue. Conclusions This analysis shows that, in patients with HIV-1 infection, a single amino acid change in HLA molecules has a substantial effect on the rate of progression to AIDS. The different consequences of HLA-B*35-PY and HLA-B*35-Px in terms of disease progression highlight the importance of the epitope specificities of closely related class I molecules in the immune defense against HIV-1

Structure of the trypanosome transferrin receptor reveals mechanisms of ligand recognition and immune evasion.

To maintain prolonged infection of mammals, African trypanosomes have evolved remarkable surface coats and a system of antigenic variation1. Within these coats are receptors for macromolecular nutrients such as transferrin2,3. These must be accessible to their ligands but must not confer susceptibility to immunoglobulin-mediated attack. Trypanosomes have a wide host range and their receptors must also bind ligands from diverse species. To understand how these requirements are achieved, in the context of transferrin uptake, we determined the structure of a Trypanosoma brucei transferrin receptor in complex with human transferrin, showing how this heterodimeric receptor presents a large asymmetric ligand-binding platform. The trypanosome genome contains a family of around 14 transferrin receptors4, which has been proposed to allow binding to transferrin from different mammalian hosts5,6. However, we find that a single receptor can bind transferrin from a broad range of mammals, indicating that receptor variation is unlikely to be necessary for promiscuity of host infection. In contrast, polymorphic sites and N-linked glycans are preferentially found in exposed positions on the receptor surface, not contacting transferrin, suggesting that transferrin receptor diversification is driven by a need for antigenic variation in the receptor to prolong survival in a host

Open-circuit voltage increase of GaSb/GaAs quantum ring solar cells under high hydrostatic pressure

Hydrostatic pressure can be used as a powerful diagnostic tool to enable the study of lattice dynamics, defects, impurities and recombination processes in a variety of semiconductor materials and devices. Here we report on intermediate band GaAs solar cells containing GaSb quantum rings which exhibit a 15% increase in open-circuit voltage under application of 8 kbar hydrostatic pressure at room temperature. The pressure coefficients of the respective optical transitions for the GaSb quantum rings, the wetting layer and the GaAs bulk, were each measured to be ~10.5±0.5 meV/kbar. A comparison of the pressure induced and temperature induced bandgap changes highlights the significance of the thermal energy of carriers in intermediate band solar cells

Private Computation of Polynomials over Networks

This study concentrates on preserving privacy in a network of agents where each agent seeks to evaluate a general polynomial function over the private values of her immediate neighbors. We provide an algorithm for the exact evaluation of such functions while preserving privacy of the involved agents. The solution is based on a reformulation of polynomials and adoption of two cryptographic primitives: Paillier as a Partially Homomorphic Encryption scheme and multiplicative-additive secret sharing. The provided algorithm is fully distributed, lightweight in communication, robust to dropout of agents, and can accommodate a wide class of functions. Moreover, system theoretic and secure multi-party conditions guaranteeing the privacy preservation of an agent's private values against a set of colluding agents are established. The theoretical developments are complemented by numerical investigations illustrating the accuracy of the algorithm and the resulting computational cost.Comment: 11 pages, 2 figure