Using random telephone sampling to recruit generalizable samples for family violence studies.

Convenience sampling methods predominate in recruiting for laboratory-based studies within clinical and family psychology. The authors used random digit dialing (RDD) to determine whether they could feasibly recruit generalizable samples for 2 studies (a parenting study and an intimate partner violence study). RDD screen response rate was 42-45%; demographics matched those in the 2000 U.S. Census, with small- to medium-sized differences on race, age, and income variables. RDD respondents who qualified for, but did not participate in, the laboratory study of parents showed small differences on income, couple conflicts, and corporal punishment. Time and cost are detailed, suggesting that RDD may be a feasible, effective method by which to recruit more generalizable samples for in-laboratory studies of family violence when those studies have sufficient resources. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Before children: Preparenthood cognitions of distressed and husband-to-wife aggressive couples.

Positive and negative cognitions about parenthood were assessed in a sample of recently married childless spouses who were in nondistressed, distressed, and husband-to-wife (H-to-W) aggressive marriages (328 husbands and 331 wives). As predicted, maritally distressed spouses held more negative cognitions about parenthood than did nondistressed spouses. Results indicated that spouses in H-to-W aggressive marriages expected parenthood to be a more unpredictable and difficult job than spouses in marriages not involving H-to-W aggression. Wives also reported more fears that having a child would result in a loss of freedom than did husbands. No distress, H-to-W aggression level, or gender differences were obtained for positive preparenthood cognitions. Finally, wives' but not husbands' positive and negative preparenthood cognitions at 6 months of marriage were able to predict parenthood status at 30 months of marriage. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A comparative study of wireless communication network configurations for medical applications

A comparative study of the performance characteristics of five multiple access configurations for a wireless communication network is presented and evaluated within the context of the medical field of application. A universal variable has been defined for comparison between the alternative configurations, embodying the data rate, number of channels, power consumption, and bandwidth requirements. Special medical specifications have been accommodated, while the broader applications of this approach have been addressed. CDMA is indicated as the preferred method, over ALOHA, slotted ALOHA, CSMA, and polling.     

Study of the radical mechanism of iodine-catalyzed isomerization of conjugated diene systems

The iodine-catalyzed Z/E-isomerization of internal conjugated dienes in the dark, to form a thermodynamic equilibrium mixture, was found to be a radical process with an activation energy of 12.4±1.2 kcal/ mol. The effects of antioxidants on the reaction, both in the dark and in sunlight, were studied. In both processes the radical isomerization was slowed down, probably through radical scavenging.     

The Effects of Random Message Sizes on the Performance of the CSMA/CD Protocol

We present a performance model of the carrier-sense multiple-access protocol with collision detection when each message consists of a geometrically distributed number of packets. We solve the model analytically and present numerical evidence that throughput degrades slightly when the mean number of packets per message is increased and the load is kept constant. The numerical examples indicate that the average response time of a message is approximately proportional to the average number of packets per message. We also derive a general relation between throughput and average response time that provides a theoretical explanation of these results.     

On the misperception of variability.

It has long been claimed that people perceive the world as less variable and more regular than it actually is. Such misperception, if shown to exist, could explain some perplexing behaviors. However, evidence supporting the claim is indirect, and there is no explanation of its cause. As a possible cause, the authors suggest that people use sample variability as an estimate of population variability. This is so because the sampling distribution of sample variance is downward attenuated, the attenuation being substantial for sample sizes that people consider. Results of 5 experiments show that people use sample variability, uncorrected for sample size, in tasks in which a correction is normatively called for, and indeed perceive variability as smaller than it is. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Delta-aminolevulinic acid-induced fluorescence in normal human lymphocytes

Endogenously generated protoporphyrin IX (PpIX) from exogenous delta-aminolevulinic acid (ALA) has the photodynamic capacity to inactive cancer cells of different origins. The aim of this study was to characterize the ability of normal lymphocytes to transform ALA into PpIX in order to appreciate through further studies changes in pathologic lymphocytes. We investigated in this study PpIX synthesis by normal human lymphocytes using a confocal laser microspectrofluorometer. Live lymphocytes were identified by monoclonal antibody fluorescent labeling. B and T lymphocytes synthesized PpIX (80-100 counts), with a maximum being reached after 4 h ALA incubation. When T subpopulations of lymphocytes were labeled, T4 and T8 changes in fluorescence kinetics were similar, reaching a maximum after 5 h ALA incubation. The influence of monoclonal antibody labeling on this delayed increase for maximum fluorescence is considered. Phytohemagglutinin (PHA, incubation for 72 h) lymphocyte stimulation induced a 100% increase in PpIX fluorescence for T lymphocytes, whereas pokeweed mitogen activation produced an increase of about 50% in the B- or T-lymphocyte signal. Finally, the scanning fluorescence image clearly indicated the inhomogeneity of cytoplasmic ALA-induced PpIX fluorescence, which was probably due to the distribution of mitochondria. The influence of this heterogeneity on PpIX photosensitivity effects is discussed.     

Towards a Middle East at peace: hidden issues in Arab–Israeli hydropolitics

When peace negotiations do one day resume between Israelis and Arabs, shared water resources will again take centre stage, acting both as an irritant between the parties, and as a tremendous inducement to reach agreement. The ‘hidden’ hydropolitical issues that will need to be resolved between Israel, Lebanon and Syria in the course of eventual boundary talks are considered. Two of these issues, the village of Ghajar and its relation to the Wazani Springs, and the possibility of groundwater flow from the Litani to the Jordan headwaters, change the fundamental understanding of the relationship between hydrologic and political claims, and could threaten the entire approach to water negotiations both between Israel and Syria and between Israel and Lebanon. Fortunately, other agreements within the basin can inform the path solutions here might take. The most critical step towards conflict resolution is separating the concepts of territorial sovereignty from water security. This can be done most effectively by offering joint management, monitoring and enforcement strategies, as well as encouraging greater transparency in water data across boundaries.     

Hypersequents,logical consequence and intermediate logics for concurrency

The existence of simple semantics and appropriate cut-free Gentzen-type formulations are fundamental intrinsic criteria for the usefulness of logics. In this paper we show that by using hypersequents (which are multisets of ordinary sequents) we can provide such Gentzen-type systems to many logics. In particular, by using a hypersequential generalization of intuitionistic sequents we can construct cut-free systems for some intermediate logics (including Dummett's LC) which have simple algebraic semantics that suffice, e.g., for decidability. We discuss the possible interpretations of these logics in terms of parallel computation and the role that the usual connectives play in them (which is sometimes different than in the sequential case).