Welfare effects of fixed and percentage-expressed child support awards

Over the last decade a large number of states have significantly altered their legal statutes concerning the disposition of divorce cases involving children. In particular, many states have increasingly employed percentage-expressed orders in which child support obligations in a given period are determined as a proportion of the contemporaneous income of the noncustodial parent. In contrast to more traditional systems in which obligations were set in fixed nominal terms at the time of the divorce settlement and were infrequently (or never) updated, the dynamic system has the advantages of allowing children (and the custodial parent) an opportunity to share in the general income gains experienced by the noncustodial parent over the life cycle and of possibly alleviating some noncompliance problems. In this paper we conduct a rather extensive theory-based empirical investigation of the effects of these systems on the income process for divorced fathers and the child support transfer decision. We estimate a flexible statistical model for the income- generation process for divorced fathers which encompasses the period both before and after the divorce. We interpret the estimates from this model to indicate small behavioral effects of the type of order on postdivorce income, but nonrandom assignment (in terms of the means and variances of predivorce income) into the percentage-expressed-order state. Our analysis of the effects of the order type on child support transfers is divided into two parts. In the first, a "reduced form" analysis, we investigate whether or not the divorced father's regime defined as the order type and withholding status can be considered exogenous vis-a-vis the transfer decision, and examine the relative effects of the various regimes on the transfer rate. We further attempt to investigate order-type effects on compliance in the context of a structural model of the compliance decision. The results of the two analyses are for the most part consistent. Percentage orders are generally associated with lower compliance rates, though withholding tends to alleviate the problem. The highest compliance rates are associated with fixed orders coupled with withholding.

Should Grain Elevator Managers Adopt Integrated Pest Management?

Insect infestation during storage and processing causes millions of dollars of wheat damage annually in the United States. Insect infestation reduces wheat storing processing profit as well as consumer confidence in wheat food products. Meanwhile, increased concerns about insecticide use have increase interest in Integrated Pest Management (IPM) strategies. This research compares the costs of IPM and chemical-based approaches to insect control to determine why most elevator managers have not adopted IPM practices.Agribusiness,

Detection, analysis, and interpretation of teleseismic signals: 1. Compressional Phases from the Salmon Event

The travel times and amplitude spectrums of first- and later-arrival P phases from the Salmon event are computed on the basis of polarization filter outputs. The interpretation of the P wave radiation field is made in terms of crust and mantle structure using the first- and later-arrival P phases and their amplitude spectrums. The observed seismic field corresponds with that expected from a symmetric, purely compressive source. The essential features of the observed travel times and amplitudes are explained in terms of regional mantle structures. These structures provide first-order fits to the observed data and are characterized by low-velocity zones which terminate with rapid and continuous increases in velocity near depths of 130 km. The velocity structures also show a strong velocity gradient near 330 km. The regional models differ most strongly in the relative extent and magnitude of the velocity decrease in the Iow-velocity zone

Fine structure of the upper mantle

The spectral amplitudes and travel times of seismic body waves are used to determine mantle velocity structures appropriate to distinct structural provinces within the western continental United States. In addition to basic amplitude and time data, travel-time delays and Pn velocity data from other studies are used as constraints in the systematic inversion of the data for mantle structure. The regional structures for the upper mantle determined in this manner show collectively rather sharp zones of transition (high velocity gradients) near 150, 400, 650 km and possibly near 1000 km. Comparatively, the regional structures indicate strong lateral variations in the upper mantle structure down to 150 km and possibly as deep as 200 km. The structures appropriate to the Rocky Mountain and Colorado plateau physiographic provinces show low-velocity zones capped by high-velocity lid zones, with variability in both the lid and the low-velocity zone properties from province to province and within these provinces to a much lesser degree. The mantle properties obtained for the Basin and Range contrast sharply with the plateau and mountain structures, with the lid zone being very thin or absent and abnormally low velocities extending from, or very near, the base of a thin crust to 150 km. The velocity determinations are coupled with estimates of the variation of the intrinsic dissipation function (Q) as a function of depth and frequency. These results show a pronounced low-Q zone corresponding to the average low-velocity zone depth range for the velocity models. The data suggest a frequency-dependent Q, with Q increasing with frequency. In total the results of the study strongly suggest phase transitions in the mantle, including a partially melted region corresponding to the low-velocity zone, the latter being highly variable in its properties over the region studied and strongly correlated with tectonic activity

Theoretical Effect of Yield and Burst Height of Atmospheric Explosions on Rayleigh Wave Amplitudes

Theoretical seismograms for fundamental mode Rayleigh waves were calculated for atmospheric point sources over oceanic and over continental Earth models, as recorded at an epicentral distance of 10000 km. Yields were uniformly distributed over the range 1 kT-10 MT, for source altitudes in the range 0.3-92.0 km. The Earth structures used were those of Gutenberg and of Anderson and Toksöz. The source models were point mass-injection and energy-injection sources at altitude, as well as a distributed pressure pulse at the surface of the Earth. It was found that: (1) as far as Rayleigh wave excitation is concerned, the mass-injection and energy-injection sources are equivalent; (2) for low altitudes the Rayleigh wave excitation is independent of source type, but at intermediate altitudes the surface overpressure source predicts greater amplitudes than the other two source models; (3) for most altitudes, the energy coupling from the atmosphere into Rayleigh waves is more efficient for the continental Earth structure than for the oceanic structure; (4) Rayleigh wave amplitude is more sensitive to yield than to burst height (5) dependence of Rayleigh wave amplitude is less than the cube root relation for low-yield explosions at intermediate altitudes but greater for high-yield explosions at near-surface altitudes; (6) spectral splitting ratios do not show a systematic variation with yield and burst height

A Comparative Study of the Elastic Wave Radiation from Earthquakes and Underground Explosions

A detailed analysis of the surface wave radiation from two underground explosions (BILBY and SHOAL) and an earthquake near Fallon, Nevada, whose epicentre is only 60 km from SHOAL, indicates that: (1) at long periods the surface wave radiation from the earthquake can be explained by a pure quadrupole (double couple) source, but at higher frequencies the radiation pattern contains asymmetries which suggest effects due to rupture propagation; these would require higher-order multipole terms in the source equivalent representation; (2) the surface waves from the explosions can be explained by superimposed monopole and quadrupole sources, with no indication of higher-order multipole terms, at least in the period range comparable to that in which the earthquake signal was recorded; (3) the principal conclusion of this study is that the anomalous radiation from the explosions is probably due to stress relaxation around the shock-generated shatter zone and not due to earthquake triggering. Comparative analysis of SHOAL and FALLON shows that: (1) the ratio of the Love wave amplitude generated by the earthquake to the Love wave amplitude from the explosion increases with period, which implies a larger source dimension for FALLON; (2) the normalized spectral ratio of Love wave amplitude to Rayleigh wave amplitude, considered as a function of period, is nearly constant and close to unity for the explosions, but larger for the earthquake by a factor of two or three, and increasing with period. These differences might be useful in distinguishing earthquakes from explosions (at least in the magnitude range of the events used in this study, m_b 4.4 and above), as well as for estimating source parameters, such as stress, which are of fundamental geophysical interest

Day-to-day variation of salivary cortisol and dehydroepiandrosterone (DHEA) in children from a rural Dominican community

This study examines day-to-day patterns of salivary cortisol and dehydroepiandrosterone (DHEA) under baseline conditions and in response to mild stress among 59 children residing in a rural Caribbean village. Cortisol secretion showed the typical circadian variation with high levels in the morning. Children showed significant increases of cortisol before and during a videotaped interview when compared to routine days. DHEA levels were positively associated with cortisol levels; however, within-day secretion of salivary DHEA was more stable than cortisol and DHEA levels did not change significantly during the day. Average DHEA concentrations were positively associated with age but did not show the sharp increase that is usually observed at the onset of adrenarche. These results highlight both similarities and differences in the secretion of cortisol and DHEA during childhood among rural and industrialized human populations

Assessing a Novel Adaptation to CCI Devices to Model Human Mild Traumatic Brain Injury

Background: Traumatic Brain Injuries (TBIs) are a health crisis with over a million people suffering injuries each year in the United States. The majority of TBIs are mild injuries which often produce no period of unconsciousness and no gross damage to the brain or skull. A range of TBI animal models exist but many produce injuries too severe to characterize as mild. One TBI induction method commonly used is Controlled Cortical Impact (CCI) devices. New Method: The purpose of this study is to assess a novel adaptation to CCI devices that allows for the induction of mild injuries that mimic human mild TBI (mTBI). In this apparatus, the mouse is placed on an elevated platform which utilizes a sensor to collapse the platform as the impactor hits the head. Results: On the first day of injury, the repetitive dropping platform group had a significantly lower Time to Righting (TTR) than both control and single hit stationary platform groups. Additionally, on the first day of injury the single-hit stationary group had a significantly increased Time to Ambulation (TTA) compared to all other groups. Furthermore, this adaptation produces significantly less GFAP than CCI injuries performed without the falling platform. Comparison with existing models: This model incorporates the high control of the CCI device that may be lost in weight-drop models of mild injury while also producing translational mild injuries. Conclusion: This adaptation can be used in any CCI research lab to translationally study mild injuries. This will facilitate murine research into mTBI

Rationalizing Child Support Decisions

society ; family