Effects of parent-child affective quality during high school years on subsequent substance use

The literature indicates that the quality of affective relationships between youth and parents is associated with lower levels of a range of problem behaviors during childhood, early and late adolescence. While the protective effect of parental monitoring on substance use in the high school and post high school years has been demonstrated, there is a knowledge gap concerning effects of parent-child affective quality (PCAQ) during the same periods. We tested a conceptual theoretical model to examine the effects of PCAQ on substance use following high school. The sample was from a RCT that assessed adolescents in rural Iowa from the seventh grade through two years after high school (N=456). We specified direct effects of PCAQ in 12th grade on drunkenness, smoking and illicit drug use during the two years immediately following high school graduation. We also specified the effects of early substance use initiation (alcohol, tobacco and marijuana use reported at baseline) on later use. The direct effect of PCAQ in 12th grade on substance use was significant for all substances during at least one of the two years past graduation (ypg). Results were: drunkenness 1 ypg, β=-.126, p<.05; smoking 1 ypg, β=-.119, p<.05; 2 ypg, β=-.146, p<.05; illicit drug use 2 ypg, β=-.165, p<.05. Some significant indirect effects of PCAQ at baseline, via PCAQ at 12th grade, were found. Results also indicated significant direct effects of early initiation on two of the three substances, albeit with a different pattern of effects over time for each substance by years post high school. Importantly, while early initiation remains the strongest predictor of long-term tobacco and illicit drug use, results show how PCAQ might reduce its harmful effects.peer-reviewe

Trogocytosis by Entamoeba histolytica Mediates Acquisition and Display of Human Cell Membrane Proteins and Evasion of Lysis by Human Serum.

We previously showed that Entamoeba histolytica kills human cells through a mechanism that we termed trogocytosis ("trogo-" means "nibble"), due to its resemblance to trogocytosis in other organisms. In microbial eukaryotes like E. histolytica, trogocytosis is used to kill host cells. In multicellular eukaryotes, trogocytosis is used for cell killing and cell-cell communication in a variety of contexts. Thus, nibbling is an emerging theme in cell-cell interactions both within and between species. When trogocytosis occurs between mammalian immune cells, cell membrane proteins from the nibbled cell are acquired and displayed by the recipient cell. In this study, we tested the hypothesis that through trogocytosis, amoebae acquire and display human cell membrane proteins. We demonstrate that E. histolytica acquires and displays human cell membrane proteins through trogocytosis and that this leads to protection from lysis by human serum. Protection from human serum occurs only after amoebae have undergone trogocytosis of live cells but not phagocytosis of dead cells. Likewise, mutant amoebae defective in phagocytosis, but unaltered in their capacity to perform trogocytosis, are protected from human serum. Our studies are the first to reveal that amoebae can display human cell membrane proteins and suggest that the acquisition and display of membrane proteins is a general feature of trogocytosis. These studies have major implications for interactions between E. histolytica and the immune system and also reveal a novel strategy for immune evasion by a pathogen. Since other microbial eukaryotes use trogocytosis for cell killing, our findings may apply to the pathogenesis of other infections.IMPORTANCE Entamoeba histolytica causes amoebiasis, a potentially fatal diarrheal disease. Abscesses in organs such as the liver can occur when amoebae are able to breach the intestinal wall and travel through the bloodstream to other areas of the body. Therefore, understanding how E. histolytica evades immune detection is of great interest. Here, we demonstrate for the first time that E. histolytica acquires and displays human cell membrane proteins by taking "bites" of human cell material in a process named trogocytosis ("trogo-" means "nibble"), and that this allows amoebae to survive in human serum. Display of acquired proteins through trogocytosis has been previously characterized only in mammalian immune cells. Our study suggests that this is a more general feature of trogocytosis not restricted to immune cells and broadens our knowledge of eukaryotic biology. These findings also reveal a novel strategy for immune evasion by a pathogen and may apply to the pathogenesis of other infections

The GZK Bound and Strong Neutrino-Nucleon Interactions above 10^19eV: a Progress Report

Cosmic ray events above 10^19 eV have posed a fundamental problem for more than thirty years. Recent measurements indicate that these events do not show the features predicted by the GZK bound. The events may, in addition, display angular correlations with point sources. If these observations are confirmed for point sources further than 50 - 100 Mpc, then strong interactions for the neutrino are indicated. Recent work on extra spatial dimensions provides a context for massive spin-2 exchanges capable of generating cross sections in the 1 - 100 mb range, as indicated by data. Applications of extra-dimension physics are controversial, and we comment on several contentious issues.Comment: 4 pages, 1 figure; talk by JPR at 7th Conference on the Intersections of Particle and Nuclear Physics, Quebec City, May, 200

The Association Between the Need for Affiliation and Traveler Type with the Motivation for Travel

The purpose of the study was to develop a conceptual framework and measures to identify the association of the need for affiliation and traveler profiles in shifts of motivations for travel. The instrument contained four types of questions: the revised Mehrabian Affiliative Tendency Scales, Driver\u27s Recreation Experience Preference Scales, traveler and demographic profile questions. There was a significant difference between the factor mean scores for four of the five travel motivation factors among the three sub-groups as determined by their respective levels of affiliation. The results revealed that there was a significant difference between the factor mean scores for travel motivation among the three subgroups as determined by their respective preference for types of travel

Dissolution Rates of Allophane, Fe-Allophane, and Hisingerite and Implications for Aqueous Alteration on Mars and in Potential Returned Martian Samples

Recent measurements from Mars document X-ray amorphous/nano-crystalline materials in multiple locations across the planet. However, despite their prevalence, little is known about these materials or what their presence implies for the history of Mars. The amorphous component of the martian soil in Gale Crater has an X-ray diffraction pattern that can be partially fit with allophane (approximately Al2O3•(SiO2)1.3-2•(H2O)2.5-3), as well as low-temperature water release consistent with allophane. The chemical data from Gale Crater suggest that other silicate phases similar to allophane, such as Fe-substituted allophane (here, approximately (Fe2O3)0.01(Al2O3)0.99(SiO2)2•3H2O) and hisingerite (approximately Fe3+2Si2O5(OH)4•(H2O)), may also be present. In order to investigate the properties of these poorly crystalline components of the martian soil, we synthesized allophane, Fe-substituted allophane, and hisingerite; characterized the synthetic materials by infrared spectroscopy, electron microscopy, X-ray diffraction, and evolved gas analysis; and performed dissolution experiments at acidic, near-neutral, and alkaline conditions in order to determine dissolution kinetics and alteration phases for these poorly crystalline materials. Our analyses demonstrate that allophane, Fe-allophane, and hisingerite are appropriate analogs for silicate phases in the martian amorphous soil component. These poorly crystalline materials dissolve rapidly at all experimental pH conditions, indicating that similar materials on Mars must have had limited interaction with liquid water since their formation. For allophane, logrdiss = -11.05 – 0.088 × pH; for Fe-allophane, logrdiss = -11.09 – 0.091 × pH; and for hisingerite, logrdiss = -11.49 – 0.032 × pH. Additionally, incipient phyllosilicate phases form in hisingerite and allophane under high pH conditions, but are much more sparse at low pH, which, combined with the enrichment of Fe expected from weathering, may be a useful tool for examining returned samples of martian soils for evidence of past aqueous alteration

Utilizing the Goodrich Attributes to Profile Utah Travelers\u27 Motivations

Numerous attempts have been made to profile tourist motivations and link them to attraction choice. This study attempted to utilize the Goodrich attributes to determine traveler\u27s motivations and perceptions regarding attractions in Utah. The information derived from this study was helpful in directing future marketing efforts

Structure of organizational trust in military-type and civilian organizations: Validation of the Organizational Trust Questionnaire

Contemporary research on organizational trust views it as either rational or relational phenomenon that is a result of interpersonal bonds or cooperative relationships between the trusting parties. Resent studies agree that a certain degree of trust must be embedded in and enacted through organizational interactions and structures, taking trust from a purely interpersonal phenomenon to a more complex organizational phenomenon that has multiple antecedents;This study hypothesizes that that an organizational member\u27s intention to trust others in the organization is affected by six factors: (1) the individual\u27s propensity to trust, (2) co-workers\u27 character and behaviors, (3) bosses\u27 character and behavior, (4) organizational structures, (5) interactions outside of the organization, and (6) the individual\u27s propensity to distrust. The study also suggests that individual intention to trust others in organizations varies depending on the degree of organizational formalization and centralization;To confirm the existence of the proposed factors and explore the potential influence of structural dimensions on individual intention to trust, the Organizational Trust Questionnaire (the OTQ) was constructed and distributed to the employees of a law enforcement agency and a university. The data was analyzed using exploratory and confirmatory factor analyses and the Structural Equations Modeling technique;The findings validate the OTQ and establish its usability in both civilian and military-type organizations. The results demonstrate that faculty members and professional and scientific employees of the university have higher levels of intention to trust than sworn officers of a law enforcement agency and merit employees of the university. These differences are attributed to the differences in levels of centralization and formalization in the two organizations

Hadron Helicity Violation in Exclusive Processes: Quantitative Calculations in Leading Order QCD

We study a new mechanism for hadronic helicity flip in high energy hard exclusive reactions. The mechanism proceeds in the limit of perfect chiral symmetry, namely without any need to flip a quark helicity. The fundamental feature of the new mechanism is the breaking of rotational symmetry of the hard collision by a scattering plane in processes involving independent quark scattering. We show that in the impulse approximation there is no evidence for of the helicity violating process as the energy or momentum transfer $Q^2$ is increased over the region 1 GeV^2 < Q^2 < 100 GeV^2. In the asymptotic region Q^2> 1000 GeV^2, a saddle point approximation with doubly logarithmic accuracy yields suppression by a fraction of power of Q^2. ``Chirally--odd" exclusive wave functions which carry non--zero orbital angular momentum and yet are leading order in the high energy limit, play an important role.Comment: uuencoded LaTeX file (21 pages) and PostScript figure