Modeling aviation baggage screening security systems: a case study

Aviation security protects vital national interests, as well as passengers and aircraft. Key components of an aviation security system include baggage and passenger screening devices and operations. Determining how and where to assign (deploy) such devices can be quite challenging. Moreover, even after such systems are in place, it can be difficult to measure their effectiveness. This paper describes how discrete optimization models can be used to address these questions, based on three performance measures that quantify the effectiveness of airport baggage screening security device systems. These models are used to solve for optimal airport baggage screening security device deployments considering the number of passengers on a set of flights who have not been cleared using a security risk assessment system in use by the Federal Aviation Administration (i.e., passengers whose baggage is subjected to screening), the number of flights in this set, and the size of the aircraft for such flights. Several examples are provided to illustrate these results, including an example that uses data available from the Official Airline Guide.     

Greater task difficulty amplifies the facilitatory effect of des-glycinamide arginine vasopressin on appetitively motivated learning.

39 3–6 mo old male Long-Evans rats were trained in a discrete-trial forward autoshaping paradigm to touch an extended lever to earn food pellets. Reinforcement was delivered either simultaneously with or 6 sec after lever retraction, which occurred either noncontingently after 15 sec or when the Ss touched the lever. Treatment with subcutaneous des-glycinamide arginine vasopressin (DGAVP [15 μg/kg]) 1 hr before sessions increased the rate of acquisition of the extended-lever-touch response and also facilitated development of intertrial (adjunctive) nose poking. The effects of the peptide were more robust in the more difficult delayed reinforcement task. Results are consistent with previous findings that DGAVP lacks the classical peripheral activity of vasopressin. In both experiments, peptide treatment was terminated before asymptotic levels of performance were attained; the continued facilitation of acquisition in treated groups suggests a specific enhancement of learning and/or enhanced memory retrieval. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Exclusion of BMP6 as a candidate gene for cleidocranial dysplasia

Cleidocranial dysplasia (CCD) is an autosomal dominant, generalized skeletal dysplasia in humans that has been mapped to the short arm of chromosome 6. We report linkage of a CCD mutation to 6p21 in a large family and exclude the bone morphogenetic protein 6 gene (BMP6) as a candidate for the disease by cytogenetic localization and genetic recombination. CCD was linked with a maximal two-point LOD score of 7.22 with marker D6S452 at theta = 0. One relative with a recombination between D6S451 and D6S459 and another individual with a recombination between D6S465 and CCD places the mutation within a 7 cM region between D6S451 and D6S465 at 6p21. A phage P1 genomic clone spanning most of the BMP6 gene hybridized to chromosome 6 in band region p23-p24 using FISH analysis, placing this gene cytogenetically more distal than the region of linkage for CCD. We derived a new polymorphic marker from this same P1 clone and found recombinations between the marker and CCD in this family. The results confirm the map position of CCD on 6p21, further refine the CCD genetic interval by identifying a recombination between D6S451 and D6S459, and exclude BMP6 as a candidate gene.     

Calculation of the concentrated flux density distribution in parabolic trough collectors by a semifinite formulation

A first integral of the concentrated radiant flux density for trough concentrators is derived by exploiting the symmetry of these cylindrical systems. The resulting semifinite formulation yields both conceptual advantages and computational efficiency. The formulation is illustrated by application to the parabolic trough concentrator. The elementary example of determining the concentrated flux density at the nominal focal plane is first considered. The more realistic case of a round absorber tube, which can shade the reflector, centered on the focal line is also studied. This more practical geometry, which corresponds to most commercial designs, has previously received little attention in the open literature. These applications illustrate that the semifinite formulation presented herein can be a simple and useful tool for the analysis and design of trough concentrators.     

The Benefits of a "Sidelong" Approach to Self-Esteem Need Satisfaction: Comment on Crocker and Park (2004).

J. Crocker and L. E. Park (2004) have achieved an admirable integration of the self-esteem literature with their claim that self-esteem is better conceived of as a dynamic human striving, rather than as a passive state or personality characteristic. However, the costs of self-esteem striving may be overstated--these costs may arise only in certain constrained cases. Also, although Crocker and Park suggested that self-esteem is not a true psychological need, there is evidence that humans in all cultures need to feel a positive sense of self-worth (K. M. Sheldon, in press). Problems may arise only when people strive too directly for this feeling, rather than deriving it as a natural concomitant of non-self-focused goals. A "sidelong" approach to self-esteem need satisfaction is advocated in this commentary. (PsycINFO Database Record (c) 2010 APA, all rights reserved)