Forgiveness Motives Among Evangelical Christians: Implications for Christian Marriage and Family Therapists

Therapists and researchers interested in forgiveness can learn from those who have experienced interpersonal wounds and have chosen to forgive. We interviewed 20 evangelical Christian forgivers, asking about motives for forgiveness. Transcripts were analyzed using qualitative methods. Five categories of motivation are presented: comfort, duty, relational, humility/empathy, and Christian beliefs. Respondents described multiple motives for forgiveness, often combining a desire for comfort or a sense of duty with their Christian beliefs. Four implications for Christian marriage and family therapists are discussed: Expect diversity, avoid moralistic views of motives, remember religious resources in the forgiveness process, and expect benefits, but not immediately

Characterization of Simulated Low Earth Orbit Space Environment Effects on Acid-spun Carbon Nanotube Yarns

The purpose of this study is to quantify the detrimental effects of atomic oxygen and ultraviolet (UV) C radiation on the mechanical properties, electrical conductivity, and piezoresistive effect of acid-spun carbon nanotube (CNT) yarns. Monotonic tensile tests with in-situ electrical resistance measurements were performed on pristine and exposed yarns to determine the effects of the atomic oxygen and UVC exposures on the yarn’s material properties. Both type of exposures were performed under vacuum to simulate space environment conditions. The CNT yarns’ mechanical properties did not change significantly after being exposed to UV radiation, but were significantly degraded by the atomic oxygen exposure. The electrical conductivity of the yarn was not significantly affected by either exposure. The piezoresistive effect did not significantly change due to atomic oxygen exposure, but was significantly enhanced as a result of the UV exposure. Scanning electron microscopy revealed significant erosion due to atomic oxygen exposure, but the UV exposure did not significantly change the appearance of the yarn’s external surface. Raman spectroscopy showed that both exposure types induced significant structural disorder in the surface level CNTs. Focused ion beam milling of a UVC exposed yarn revealed that the depth of the induced disorder was very shallow

Variable Hard X-ray Emission from the Candidate Accreting Black Hole in Dwarf Galaxy Henize 2-10

We present an analysis of the X-ray spectrum and long-term variability of the nearby dwarf starburst galaxy Henize 2-10. Recent observations suggest that this galaxy hosts an actively accreting black hole with mass ~10^6 M_sun. The presence of an AGN in a low-mass starburst galaxy marks a new environment for active galactic nuclei (AGNs), with implications for the processes by which "seed" black holes may form in the early Universe. In this paper, we analyze four epochs of X-ray observations of Henize 2-10, to characterize the long-term behavior of its hard nuclear emission. We analyze observations with Chandra from 2001 and XMM-Newton from 2004 and 2011, as well as an earlier, less sensitive observation with ASCA from 1997. Based on detailed analysis of the source and background, we find that the hard (2-10 keV) flux of the putative AGN has decreased by approximately an order of magnitude between the 2001 Chandra observation and exposures with XMM-Newton in 2004 and 2011. The observed variability confirms that the emission is due to a single source. It is unlikely that the variable flux is due to a supernova or ultraluminous X-ray source, based on the observed long-term behavior of the X-ray and radio emission, while the observed X-ray variability is consistent with the behavior of well-studied AGNs.Comment: 7 pages, 4 figures, 2 tables; accepted for publication in Ap

Quantifying the Effects of Hyperthermal Atomic Oxygen and Thermal Fatigue Environments on Carbon Nanotube Sheets for Space-Based Applications

The effects of atomic oxygen and thermal fatigue on two different types of carbon nanotube sheets were studied. One set was treated with nitric acid, while the other set was left untreated. Monotonic tensile tests were performed before and after exposure to determine the effects of either exposure type on the sheets’ mechanical properties. Electrical conductivity and electromagnetic interference measurements were recorded to determine the effects of AO-exposure and thermal cycling on the sheets’ electrical properties. Neither exposure type affected the sheets’ specific strengths. Both exposure types increased the sheets’ specific stiffnesses and decreased the sheets’ strains at failure. The electrical conductivity of both sheets decreased due to the different exposure types, while the EMI shielding effectiveness was unaffected. Scanning electron microscopy was used to observe any changes in the sheets’ surface morphologies, while energy-dispersive X-ray spectroscopy was used to determine the effects of AO on the sheets’ chemical makeup

Relating polymer matrix composite delamination behavior to constituent properties

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2004.Includes bibliographical references (p. 183-194).Developing predictive capabilities of composite material behavior from constituent properties is an important component of accelerating materials insertion. Many models exist that accomplish this objective for a range of material properties, but no such method is available for delamination properties. This thesis explores the issues associated with predicting polymer matrix composite Mode I delamination behavior from constituent properties by examining the topic from a variety of perspectives. Nanoindentation tests of matrix materials in composites and their associated neat polymers analyze the assumption that neat matrix properties are the same as unconstrained in situ properties and therefore may be used in models predicting composite behavior from constituent properties. Quasi-static and fatigue fracture experiments using a graphite/epoxy composite and its neat resin at a variety of temperatures and loading rates allow for an examination of the dominant mechanisms involved in the fracture process, an analysis of the shifts in quasi-static behavior with temperature and potential implications for fatigue predictions, and measurement of values that will act as inputs and verification of a delamination initiation model. A global-local finite element model of a double cantilever beam specimen is used to study the prediction of delamination initiation by examining inelastic matrix deformation at the crack tip. In addition, a fiber bridging fatigue model is created to analyze crack propagation data that effectively separates the bridging and resin crack tip contributions. The final component of the thesis is to tie the various experimental and analytical studies together to create methodologies that may be used in a design or research environment(cont.) to accelerate materials insertion. An important conclusion from the thesis is that quantitative predictions of composite fracture behavior using unmodified neat matrix properties is not feasible, but the constrained matrix properties may be used to predict composite delamination behavior. It is also shown that following a process of implementing mechanism-based models in conjunction with experimental observations is essential when implementing models that bridge lengthscales.by Jeremy Ryan Gregory.Ph.D

CASTER - a concept for a Black Hole Finder Probe based on the use of new scintillator technologies

The primary scientific mission of the Black Hole Finder Probe (BHFP), part of the NASA Beyond Einstein program, is to survey the local Universe for black holes over a wide range of mass and accretion rate. One approach to such a survey is a hard X-ray coded-aperture imaging mission operating in the 10--600 keV energy band, a spectral range that is considered to be especially useful in the detection of black hole sources. The development of new inorganic scintillator materials provides improved performance (for example, with regards to energy resolution and timing) that is well suited to the BHFP science requirements. Detection planes formed with these materials coupled with a new generation of readout devices represent a major advancement in the performance capabilities of scintillator-based gamma cameras. Here, we discuss the Coded Aperture Survey Telescope for Energetic Radiation (CASTER), a concept that represents a BHFP based on the use of the latest scintillator technology.Comment: 12 pages; conference paper presented at the SPIE conference "UV, X-Ray, and Gamma-Ray Space Instrumentation for Astronomy XIV." To be published in SPIE Conference Proceedings, vol. 589

Effects of Thermal Process Parameters on Mechanical Interlayer Strength for Additively Manufactured Ultem 9085

The effects of the envelope temperature on the microstructure and mechanical strength of Ultem 9085 fused deposition modeling (FDM) components were studied. A customized build chamber was developed for a commercial 3D printer in order to control the envelope temperature during printing. Test specimens were printed in the vertical direction because their mechanical strength exhibited the greatest dependence on inter-layer adhesion and neck development. A delay was introduced between two layers in each specimen in order to create a weak region where the neck was not expected to fully develop. However, none of the specimens failed in this region. Mechanical testing revealed that neck growth was highly dependent on the envelope temperature, and the strength was shown to vary significantly (20%) based on the envelope temperature. The variability of the mechanical strength also decreased as the envelope temperature increased. Thermal imaging revealed that the cooling rate of the specimens was consistent regardless of the envelope temperature. Fracture analysis confirmed that higher envelope temperatures improved the amount of neck growth and inter-layer adhesion in the specimens. This study showed that increasing the envelope temperature created parts with higher strengths and improved consistencies

Substance Use as a Longitudinal Predictor of the Perpetration of Teen Dating Violence

The final publication is available at Springer via http://dx.doi.org/10.1007/s10964-012-9877-1.The prevention of teen dating violence is a major public health priority. However, the dearth of longitudinal studies makes it difficult to develop programs that effectively target salient risk factors. Using a school-based sample of ethnically diverse adolescents, this longitudinal study examined whether substance use (alcohol, marijuana, and hard drugs) and exposure to parental violence predicted the perpetration of physical dating violence over time. 1,042 9th and 10th grade high schools students were recruited and assessed in the spring of 2010, and 93% of the original sample completed the 1-year follow-up in the spring of 2011. Participants who had begun dating at the initial assessment and who self-identified as African American (n = 263; 32%), Caucasian (n = 272; 33%), or Hispanic (n = 293; 35%) were included in the current analyses (n = 828; 55% female). Slightly more than half of the adolescents who perpetrated dating violence at baseline reported past year dating violence at follow-up, relative to only 11% of adolescents who did not report perpetrating dating violence at baseline. Structural equation modeling revealed that the use of alcohol and hard drugs at baseline predicted the future perpetration of physical dating violence, even after accounting for the effects of baseline dating violence and exposure to interparental violence. Despite differences in the prevalence of key variables between males and females, the longitudinal associations did not vary by gender. With respect to race, exposure to mother-to-father violence predicted the perpetration of dating violence among Caucasian adolescents. Findings from the current study indicate that targeting substance use, and potentially youth from violent households, may be viable approaches to preventing the perpetration of teen dating violence

Improved protocols for functional analysis in the pathogenic fungus Aspergillus flavus

<p>Abstract</p> <p>Background</p> <p>An available whole genome sequence for <it>Aspergillus flavus </it>provides the opportunity to characterize factors involved in pathogenicity and to elucidate the regulatory networks involved in aflatoxin biosynthesis. Functional analysis of genes within the genome is greatly facilitated by the ability to disrupt or mis-express target genes and then evaluate their result on the phenotype of the fungus. Large-scale functional analysis requires an efficient genetic transformation system and the ability to readily select transformants with altered expression, and usually requires generation of double (or multi) gene deletion strains or the use of prototrophic strains. However, dominant selectable markers, an efficient transformation system and an efficient screening system for transformants in <it>A. flavus </it>are absent.</p> <p>Results</p> <p>The efficiency of the genetic transformation system for <it>A. flavus </it>based on uracil auxotrophy was improved. In addition, <it>A. flavus </it>was shown to be sensitive to the antibiotic, phleomycin. Transformation of <it>A. flavus </it>with the <it>ble </it>gene for resistance to phleomycin resulted in stable transformants when selected on 100 μg/ml phleomycin. We also compared the phleomycin system with one based on complementation for uracil auxotrophy which was confirmed by uracil and 5-fluoroorotic acid selection and via transformation with the <it>pyr4 </it>gene from <it>Neurospora crassa </it>and <it>pyrG </it>gene from <it>A. nidulans </it>in <it>A. flavus </it>NRRL 3357. A transformation protocol using <it>pyr4 </it>as a selectable marker resulted in site specific disruption of a target gene. A rapid and convenient colony PCR method for screening genetically altered transformants was also developed in this study.</p> <p>Conclusion</p> <p>We employed phleomycin resistance as a new positive selectable marker for genetic transformation of <it>A. flavus</it>. The experiments outlined herein constitute the first report of the use of the antibiotic phleomycin for transformation of <it>A. flavus</it>. Further, we demonstrated that this transformation protocol could be used for directed gene disruption in <it>A. flavus</it>. The significance of this is twofold. First, it allows strains to be transformed without having to generate an auxotrophic mutation, which is time consuming and may result in undesirable mutations. Second, this protocol allows for double gene knockouts when used in conjunction with existing strains with auxotrophic mutations.</p> <p>To further facilitate functional analysis in this strain we developed a colony PCR-based method that is a rapid and convenient method for screening genetically altered transformants. This work will be of interest to those working on molecular biology of aflatoxin metabolism in <it>A. flavus</it>, especially for functional analysis using gene deletion and gene expression.</p