Domestic Violence, Employment and Divorce

Using unique, representative data on domestic violence, we document several stylized facts on abuse: the average characteristics of abused wives and abusive husbands are markedly different than the characteristics of individuals in non-violent marriages, the vast majority of violent marriages end in divorce, and employment rates are lower for women who experience abuse. We then construct a sequential model of employment, marriage and abuse. The results indicate abuse is the primary factor in the decision to divorce and witnessing violence as a child is a strong predictor of becoming an abusive spouse. Policy experiments suggest men are more responsive to policies designed to increase the costs of abuse than women are to policies reducing the cost of leaving violent marriages and policies designed to reduce the inter-generational effects of domestic violence may be promising strategies for preventing abuse.Domestic Violence, Abuse, Employment, Marriage, Divorce

New computer system simplifies programming of mathematical equations

Automatic Mathematical Translator /AMSTRAN/ permits scientists or engineers to enter mathematical equations in their natural mathematical format and to obtain an immediate graphical display of the solution. This automatic-programming, on-line, multiterminal computer system allows experienced programmers to solve nonroutine problems

Labor Supply, Divorce and Remarriage

This paper considers the role of the entire marital history in labor market decisions. A distinction is made between married, remarried, single and divorced women in the estimation of standard participation and labor supply functions. In specifications controlling for unobserved individual heterogeneity, white remarried women are more likely to participate in the labor force and have higher labor supply than that of white married women. The results indicate that a substantial fraction of the total change in employment rates of all married women over time is due to the increase in the number of remarried women in the population. * Department of Economics, Social Science Center, University of Western Ontario, London, Ontario N6A 5C2, Canada. Correspond to [email protected]. I would like to thank Audra Bowlus, Chris Robinson, Jeff Smith and seminar participants at the University of Western Ontario for many helpful discussions and comments. Support from the Social Sciences and Humanitie..

The hyaluronan-binding serine protease from human plasma cleaves HMW and LMW kininogen and releases bradykinin

The influence of the hyaluronanbinding protease (PHBSP), a plasma enzyme with FVII- and pro-urokinase-activating potency, on components of the contact phase (kallikrein/kinin) system was investigated. No activation or cleavage of the proenzymes involved in the contact phase system was observed. The procofactor high molecular weight kininogen (HK), however, was cleaved in vitro by PHBSP in the absence of any charged surface, releasing the activated cofactor and the vasoactive nonapeptide bradykinin. Glycosoaminoglycans strongly enhanced the reaction. The cleavage was comparable to that of plasma kallikrein, but clearly different from that of coagulation factor FXIa. Upon extended incubation with PHBSP, the light chain was further processed, partially removing about 60 amino acid residues from the Nterminus of domain D5 of the light chain. These cleavage site(s) were distinct from plasma kallikrein or FXIa cleavage sites. PHBSP and, more interestingly, also plasma kallikrein could cleave low molecular weight kininogen in vitro, indicating that domains D5(H) and D6(H) are no prerequisite for kininogen cleavage. PHBSP was also able to release bradykinin from HK in plasma where the pro-cofactor circulates predominantly in complex with plasma kallikrein or FXI. In conclusion, PHBSP represents a novel kininogen-cleaving and bradykinin-releasing enzyme in plasma that shares significant catalytic similarities with plasma kallikrein. Since they are structurally unrelated in their heavy chains (propeptide), their similar in vivo catalytic activities might be directed at distinct sites where PHBSP could induce processes that are related to the kallikrein/kinin system

Accounting for Racial Differences in Marriage and Employment

The extent to which marriage market conditions explain differences in marriage and employment decisions across blacks and whites and across men and women is considered in a dynamic, two-sided model of marriage. The quantity and quality of men and women in the marriage market evolve endogenously over time in the model, and in turn influence the allocation of income within married households and the ease with which single agents attract prospective mates. The parameters of the model are estimated using a panel of young men and women from the U.S. The results highlight the responsiveness of intra-household transfers to changes in marriage market opportunities and the importance of women's options outside marriage in determining the black-white gap in marriage rates. Policy experiments suggest that improving the socio-economic characteristics of blacks and reducing the black-white gap in earnings further decreases the black marriage rate, highlighting the importance of equilibrium effects.Sex Ratio, Equilibrium Search, Intra-Household Allocation

Are predator−prey model predictions supported by empirical data? Evidence for a storm-driven shift toan alternative stable state in a crab−clam system

A dynamic systems approach can predict steady states in predator−prey interactions,but there are very few examples of predictions from predator−prey models conforming to empirical data. Here, we examined the evidence for the low-density steady state predicted by a Lotka-Volterra model of a crab−clam predator−prey system using data from long-term monitoring, and data from a previously published field survey and field predation experiment. Changepoint analysis of time series data indicate that a shift to low density occurred for the soft-shell clam Mya arenaria in 1972, the year of Tropical Storm Agnes. A possible mechanism for the shift is that Agnes altered predator−prey dynamics between M. arenaria and the blue crab Callinectes sapidus, shifting from a system controlled from the bottom up by prey resources, to a system controlled from the top down by predation pressure on bivalves, which is supported by a correlation analysis of time series data. Predator−prey ordinary differential equation models with these 2 species were analyzed for steady states, and low-density steady states were similar to previously published clam densities and mortality rates, consistent with the idea that C. sapidusis a major driver of M. arenaria population dynamics. Relatively simple models can predict shifts to alternative stable states,as shown by agreement between model predictions (this study) and published field data in this system. The preponderance of multispecies interactions exhibiting nonlinear dynamics indicatesthat this may be a general phenomenon

The Role of Domestic Abuse in Labor and Marriage Markets: Observing the Unobservables

In this paper we study the effects of abusive behavior on the labor force and marital status decisions of women. Using a unique Canadian data set on domestic violence, we estimate the effects of abuse on the marital history as well as current employment using a sequential, multi-state model. In our model, spousal abuse affects labor supply through decreases in utility from leisure as well as through reductions in productivity at work and hence the market wage. In addition, abuse is treated as an initially unobserved spousal characteristic that plays a role in the divorce decision, which in turn influences labor supply. Our analysis reveals three main findings. First, the effects of domestic abuse on employment differ across marital histories. Employment is decreasing in the presence of abuse in current and past marriages for married and divorced women, respectively, consistent with a health effect on the wage. In contrast, remarried women are more likely to work if abused in the current, but not the past, marriage. Second, domestic abuse is a dominant factor in the divorce decision, which in turn is a major determinant of employment. Finally, standard economic information such as age and education plays a minor role in the divorce decision relative to the abuse-related information

Role of habitat and predators in maintaining functional diversity of estuarine bivalves

Habitat loss is occurring rapidly in coastal systems worldwide. In Chesapeake Bay, USA, most historical oyster reefs have been decimated, and seagrass loss is expected to worsen due to climate warming and nutrient pollution. This loss of habitat may result in declining diversity, but whether diversity loss will equate to loss in ecosystem function is unknown. A bivalve survey was conducted in a variety of habitat types (seagrass, oyster shell, shell hash, coarse sand, detrital mud) in 3 lower Chesapeake Bay sub-estuaries from spring 2012 through summer 2013 to examine the correlation between bivalve densities, habitat type, habitat volume (of material retained on 3 mm mesh), and predator density. Bivalves were analyzed as functional groups based on feeding mode, living position, and predator defense strategy. On average, seagrass supported one additional functional group, and diversity was increased 68-94%, in seagrass compared to the other habitats examined. Species richness and functional group richness were positively correlated with habitat volume. The greatest densities of deposit-feeding bivalves were in detrital mud habitats, the greatest densities of thin-shelled and surface-dwelling bivalves were in seagrass habitats, and the greatest densities of armored bivalves were in oyster shell habitats. Small, thin-shelled bivalves were negatively correlated with densities of predators, including blue crabs Callinectes sapidus and cownose rays Rhinoptera bonasus. Overall, bivalve diversity was as - sociated with habitat type, habitat volume, and predator densities. These results suggest that all habitats, and particularly seagrass, play a role in maximizing bivalve functional diversity in Chesapeake Bay

Effects Of Estuarine Acidification On An Oyster-Associated Community In New South Wales, Australia

Many of the features that make estuaries among the most productive natural systems on earth also make them prone to acidification. Understanding the effects of estuarine acidification on different components of an ecological community is an important step in identifying indicators of ecosystem degradation. This study examined the impact of estuarine acidification, as a result of acid sulfate soil runoff, on wild Sydney rock oysters Saccostrea glomerata and their associated epifaunal communities in estuaries experiencing acid sulfate soil runoff in New South Wales, Australia. The responses of oysters and their invertebrate epifaunal communities to chronic acidification (greater than 6 mo; represented by oyster source site conditions) were assessed by examining the differences in oyster communities associated with moderate acidification (3.5 km from the source of acidification) or low acidification (8.2 km from the source). Oysters from moderate-or low-acidification sites were transplanted to a site with high exposure to acidification (less than 3 km from the source) or back to their original source sites (control) to mimic episodic acidification (2 wk). Epifaunal mussels Xenostrobus securis and limpets Patelloida mimula showed a negative association with oyster mortality, suggesting that these communities are closely tied to oyster survival. Oyster-associated epifaunal communities exposed to both chronic and episodic acidification were significantly different from communities with low exposure. Epifaunal communities exposed to episodic acidification were significantly less diverse than the control. Spionid and syllid worms were significantly less abundant and the mussel X. securis was significantly more abundant on oysters with moderate exposure or chronic exposure to acidification, as compared with communities from areas with low exposure to acidification. The mussel X. securis and the snail Bembicium auratum were significantly less abundant in oyster communities that were exposed to episodic acidification, as compared with the control. In systems where community composition depends on a single habitat-forming species, maintaining resistance may rely on the ability of that species to persist in the face of environmental stress