Tenure Insecurity, Transaction Costs in the Land Lease Market and their Implications for Gendered Productivity Differentials

This study sets out to assess the link between land leasing behavior and productivity differentials between male and female-headed households. A double-moral hazard model allows us to show that landlord's tenure insecurity leads to sub-optimal level of effort on tenant's part, via its impact on the likelihood of contract renewal. The landlord's enforcement ability is also shown to increase the optimal level of effort. The empirical findings support the hypothesis that female heads of households have higher tenant turnover and lower enforcement ability. The results, however, show that contract renewal is not strongly linked to productivity.productivity, female headed households, contract length, enforcement ability, Land Economics/Use, D2, Q12, Q15, C21, C7,

Parametric and Non-Parametric Estimation of Soil Conservation Impact on Productivity in the Northwestern Ethiopian Highlands

The impact of fanya juu bunds on productivity in a high rainfall area in the Ethiopian highlands is analyzed based on data from a cross section household survey with multiple plot observations per household. The results from parametric and non-parametric analysis indicated that productivity from conserved plots was lower than from non-conserved plots. The Oaxaca-Blinder productivity decomposition results showed that there was little difference in plot characteristics between conserved and non-conserved plots, however the returns to those characteristics were higher for non-conserved plots. The sensitivity analysis, increasing fodder grass production on bunds, suggests that there are possibilities to make conserved plots as productive as non-conserved ones. The findings imply that fanya juu bunds may be inappropriate to the local conditions under the existing condition. Farmers in the study area reported that these bunds h ave problem of water-logging, reduce land available for production, and create difficulties in turning the ox-drawn plough due to narrow bund sp acing. Apart from these, there is no attempt made to integrate these bunds with soil fertility management techniques. Overall, these results yield important lessons for future design of conservation technologies that have both physical and economic benefits as well as that are best suited to the local conditions.Yield decomposition, soil conservation, switching regression, stochastic dominance analysis, matching methods, Land Economics/Use, Productivity Analysis, C21, C23, Q12, Q15, Q16,

NLO Corrections to Deeply-Virtual Compton Scattering

We have calculated the NLO corrections to the twist-2 part of the deeply-virtual Compton scattering amplitude. Our results for the transverse and antisymmetric parts agree with recent calculations by Ji and Osborne and by Belitsky and M\"uller. In addition we present NLO results for the longitudinal part of the amplitude.Comment: 8 pages, Latex. Error in polarised gluonic coefficient in Eq.(8) correcte

Adjointness Relations as a Criterion for Choosing an Inner Product

This is a contribution to the forthcoming book "Canonical Gravity: {}From Classical to Quantum" edited by J. Ehlers and H. Friedrich. Ashtekar's criterion for choosing an inner product in the quantisation of constrained systems is discussed. An erroneous claim in a previous paper is corrected and a cautionary example is presented.Comment: 6 pages, MPA-AR-94-

Structural design of an in-line bolted joint for the space shuttle solid rocket motor case segments

Results of a structural design study of an in-line bolted joint concept which can be used to assemble Space Shuttle Solid Rocket Motor (SRM) case segments are presented. Numerous parametric studies are performed to characterize the in-line bolted joint behavior as major design variables are altered, with the primary objective always being to keep the inside of the joint (where the O-rings are located) closed during the SRM firing. The resulting design has 180 1-inch studs, an eccentricity of -0.5 inch, a flange thickness of 3/4 inch, a bearing plate thickness of 1/4 inch, and the studs are subjected to a preload which is 70% of ultimate. The mass penalty per case segment joint for the in-line design is 346 lbm more than the weight penalty for the proposed capture tang fix

Spectral components at visual and infrared wavelengths in active galactic nuclei

Aperture-dependent infrared photometry of active galactic nuclei are presented which illustrate the importance of eliminating starlight of the galaxy in order to obtain the intrinsic spectral distribution of the active nuclei. Separate components of emission are required to explain the infrared emission with a spectral index of alpha approx = 2 and the typical visual-ultraviolet continuum with alpha approx = 0.3 (where F(nu) varies as nu(sup-alpha). Present evidence does not allow unique determination of the appropriate mechanisms, but the characteristics of each are discussed

Measurement of band offsets in Si/Si1–xGex and Si/Si1–x–yGexCy heterojunctions

Realization of group IV heterostructure devices requires the accurate measurement of the energy band offsets in Si/Si1–xGex and Si/Si1–x–yGexCy heterojunctions. Using admittance spectroscopy, we have measured valence-band offsets in Si/Si1–xGex heterostructures and conduction-band and valence-band offsets in Si/Si1–x–yGexCy heterostructures grown by solid-source molecular-beam epitaxy. Measured Si/Si1–xGex valence-band offsets were in excellent agreement with previously reported values. For Si/Si1–x–yGexCy our measurements yielded a conduction-band offset of 100 ± 11 meV for a n-type Si/Si0.82Ge0.169C0.011 heterojunction and valence-band offsets of 118 ± 12 meV for a p-type Si/Si0.79Ge0.206C0.004 heterojunction and 223 ± 20 meV for a p-type Si/Si0.595Ge0.394C0.011 heterojunction. Comparison of our measured band offsets with previously reported measurements of energy band gaps in Si1–x–yGexCy and Si1–yCy alloy layers indicates that the band alignment is type I for the compositions we have studied and that our measured band offsets are in quantitative agreement with these previously reported results

Enhancing Social Connectedness in Anxiety and Depression Through Amplification of Positivity: Preliminary Treatment Outcomes and Process of Change.

BackgroundAnxiety and depressive disorders are often characterized by perceived social disconnection, yet evidence-based treatments produce only modest improvements in this domain. The well-established link between positive affect (PA) and social connectedness suggests that directly targeting PA in treatment may be valuable.MethodA secondary analysis of a waitlist-controlled trial (N=29) was conducted to evaluate treatment response and process of change in social connectedness within a 10-session positive activity intervention protocol-Amplification of Positivity (AMP)-designed to increase PA in individuals seeking treatment for anxiety or depression (ClinicalTrials.gov Identifier: NCT02330627). Perceived social connectedness and PA/negative affect (NA) were assessed throughout treatment. Time-lagged multilevel mediation models examined the process of change in affect and connectedness throughout treatment.ResultsThe AMP group displayed significantly larger improvements in social connectedness from pre- to post-treatment compared to waitlist; improvements were maintained through 6-month follow-up. Within the AMP group, increases in PA and decreases in NA both uniquely predicted subsequent increases in connectedness throughout treatment. However, experiencing heightened NA throughout treatment attenuated the effect of changes in PA on connectedness. Improvements in connectedness predicted subsequent increases in PA, but not changes in NA.ConclusionsThese preliminary findings suggest that positive activity interventions may be valuable for enhancing social connectedness in individuals with clinically impairing anxiety or depression, possibly through both increasing positive emotions and decreasing negative emotions