Water-soaked evidence: detectability of explosive traces after immersion in water

Various factors governing the detectability of explosive traces after being soaked in water were studied. The variables are: the type of the surface (surfaces liable to be found in aircraft were chosen), the type of explosive, the type of water (tap or seawater), and movement of the immersed surface in the water. The maximal immersion times (tmax) after which explosive detection was possible were evaluated. This datum was found to depend on the type of explosive (one of the important factors is solubility in water), the surface material and the environmental conditions (tap or seawater movement). Detection of PETN on high-density polyethylene, linoleum, glass and aluminum, by the chemical Explosive Testing Kit (ETK), was possible even after a month of soaking in seawater. In addition, it has been found that movement of bulk water around the samples with deposited explosives considerably decreases tmax values. It is, therefore, recommended to retrieve samples for explosive analysis as soon as possible and in areas where the currents of water is minimal.     

Distributive spending and presidential partisan politics

Public Choice - Do Republican and Democratic presidents vary in their geographic allocations of federal spending? Recent scholarship suggests that US presidents provide more federal outlays to...     

On the employment effect of noncompliance with the minimum wage law

A major result of the economic literature on minimum wage noncompliance is that a competitive employer who opts not to comply with the minimum wage law will employ less labor than he would have in the absence of a law. The reason for this is that noncompliance entails the risk of getting caught and punished, consequently raising the marginal cost of labor to the employer. An implicit assumption underlying this result is that noncompliance does not affect the free market wage rate facing the competitive employer. The present note shows that noncompliance will bring about a fall in the market wage rate and that if employers and workers are risk neutral, the market wage rate will fall in a way that leaves the marginal cost of labor intact. Consequently, the enactment of a minimum wage law, if not accompanied by sufficient enforcement to induce compliance, will have no effect on the level of employment.     

Identification of firearms holders by the [Fe(PDT)3](+2) complex. Quantitative determination of iron transfer to the hand and its dependence on palmar moisture levels

Quantitative data are reported for the first time on the amounts of iron, which are transferred to the hand upon holding a firearm. Iron levels between 21-315 ng/cm2 were found on volunteers' palms after a single holding of a handgun. Determination of the iron traces was accomplished spectrophotometrically using 3-(2-pyridyl)-5,6-diphenyl-1,2,4-triazine (PDT) as a complexing agent. The transfer of iron from firearms to the palm was found to be, by and large a chemical (dissolution) rather than mechanical dislodgement. The prime factor that determines the amount of iron transferred from the firearm to the hand is the moisture level on the palm. These findings are likely to be of importance in courts of law, as well as in the war against terrorism and serious crime.     

Autonomy for Contract,Refined

Law and Philosophy - In ‘The Choice Theory of Contracts’, we advance a claim about the centrality of autonomy to contract. Since publishing Choice Theory, we have engaged dozens of...     

Teachers’ Conditional Regard and Students’ Need Satisfaction and Agentic Engagement: A Multilevel Motivation Mediation Model

Teachers’ conditional positive regard and conditional negative regard are common motivational techniques in the classroom. This study investigated their respective effects on adolescent students’ agentic engagement, while considering students’ basic psychological needs for autonomy and relatedness as potential mediators. Data collected from 30 teachers and 651 7th to 10th graders (52% female) were used to test a multilevel mediation model. The results indicated that teachers’ conditional negative regard undermined students’ agentic engagement by frustrating both of their autonomy and relatedness needs. Teachers’ conditional positive regard thwarted students’ sense of autonomy, which consequently undermined their agentic engagement. The findings are discussed in terms of conditional positive and negative regard as undesirable classroom motivational practices and the mechanisms through which they operate. The discussion also notes the importance of investigating contextual factors at the classroom level.

     

Resource Priority,Fairness, and Equality-Efficiency Compromises

A central issue in theories of social justice is the potential conflict between equality and efficiency in the distribution of resources. We suggest here that resource priority is a key factor that moderates the perceived fairness of equality/efficiency compromises in resource allocation. Participants were presented with scenarios involving a policy change that pitted equality against economic efficiency in the allocation of a variety of resources that differed in their importance levels (basic versus non-basic). We found that participants gave more weight to efficiency considerations at the expense of equality in distributing non-basic (higher-level) resources than in distributing basic resources. We discuss the priority hypothesis in connection with norms of justice, human motives, the need hierarchy (deficiency versus growth needs), the consumption of basic versus non-basic resources, and the legitimacy of allocation policies. The paper is based on portions of doctoral research conducted by Eviathar Matania under the supervision of Ilan Yaniv.