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Objective: Examining the personality and well‐being correlates of positive event diversity. Background: Past research has highlighted that personality traits are linked to the frequency of daily positive events. This study is the first to examine positive event diversity, the extent to which positive events are spread across multiple types of positive life domains, as well as its personality and well‐being correlates. Method: We conducted parallel analyses of three daily diary datasets (Ns = 1919, 744, and 1392) that included evening assessment of daily positive events and affective well‐being. The Big Five personality traits were assessed in baseline surveys. Results: Positive Event Diversity was related to higher person‐mean daily positive affect but not negative affect. Higher Extraversion, Agreeableness, Openness, and lower Neuroticism were correlated with more positive event diversity. These associations became nonsignificant when controlling for positive event frequency. Positive event frequency moderated the link between positive event diversity and person‐mean affect, such that higher positive event diversity was associated with higher negative and lower positive affect for people who experienced more frequent positive events. Conclusions: No consistent evidence was found for personality as a moderator of the positive event diversity–well‐being link across the three studies. Further, the well‐being implications of positive event diversity may be better understood when interpreting them alongside indexes of positive event frequency. [ABSTRACT FROM AUTHOR]

Background: The dynamic collimation system (DCS) provides energy layer‐specific collimation for pencil beam scanning (PBS) proton therapy using two pairs of orthogonal nickel trimmer blades. While excellent measurement‐to‐calculation agreement has been demonstrated for simple cube‐shaped DCS‐trimmed dose distributions, no comparison of measurement and dose calculation has been made for patient‐specific treatment plans. Purpose: To validate a patient‐specific quality assurance (PSQA) process for DCS‐trimmed PBS treatment plans and evaluate the agreement between measured and calculated dose distributions. Methods: Three intracranial patient cases were considered. Standard uncollimated PBS and DCS‐collimated treatment plans were generated for each patient using the Astroid treatment planning system (TPS). Plans were recalculated in a water phantom and delivered at the Miami Cancer Institute (MCI) using an Ion Beam Applications (IBA) dedicated nozzle system and prototype DCS. Planar dose measurements were acquired at two depths within low‐gradient regions of the target volume using an IBA MatriXX ion chamber array. Results: Measured and calculated dose distributions were compared using 2D gamma analysis with 3%/3 mm criteria and low dose threshold of 10% of the maximum dose. Median gamma pass rates across all plans and measurement depths were 99.0% (PBS) and 98.3% (DCS), with a minimum gamma pass rate of 88.5% (PBS) and 91.2% (DCS). Conclusions: The PSQA process has been validated and experimentally verified for DCS‐collimated PBS. Dosimetric agreement between the measured and calculated doses was demonstrated to be similar for DCS‐collimated PBS to that achievable with noncollimated PBS. [ABSTRACT FROM AUTHOR]

The COVID‐19 pandemic brought new attention to the issues of food insecurity faced by individuals throughout the United States, a stressor exacerbated by disruptions to work status and supply chains. The burden of food insecurity likely carries consequences for whether individuals feel capable of pursuing their broad goals and life engagements; put differently, food insecurity may pose a threat to people perceiving a sense of purpose in life. The current study tested this claim across three samples taken during 2020 (n = 2009), 2021 (n = 1666), and 2022 (n = 1975). Participants completed inventories for perceived food insecurity, sense of purpose, depressive symptoms, and anxiety, among other measures. Results found consistent negative associations between food insecurity and sense of purpose across all three samples. In addition, food insecurity moderated associations between sense of purpose and depressive or anxiety symptoms. Sense of purpose was more strongly negatively associated with depressive and anxiety symptoms for those participants who reported no food insecurity. That said, sense of purpose remained negatively associated with psychological distress even among those reporting food insecurity. [ABSTRACT FROM AUTHOR]

Background: The Dynamic Collimation System (DCS) has been shown to produce superior treatment plans to uncollimated pencil beam scanning (PBS) proton therapy using an in‐house treatment planning system (TPS) designed for research. Clinical implementation of the DCS requires the development and benchmarking of a rigorous dose calculation algorithm that accounts for pencil beam trimming, performs monitor unit calculations to produce deliverable plans at all beam energies, and is ideally implemented with a commercially available TPS. Purpose: To present an analytical Pencil bEam TRimming Algorithm (PETRA) for the DCS, with and without its range shifter, implemented in the Astroid TPS (.decimal, Sanford, Florida, USA). Materials: PETRA was derived by generalizing an existing pencil beam dose calculation model to account for the DCS‐specific effects of lateral penumbra blurring due to the nickel trimmers in two different planes, integral depth dose variation due to the trimming process, and the presence and absence of the range shifter. Tuning parameters were introduced to enable agreement between PETRA and a measurement‐validated Dynamic Collimation Monte Carlo (DCMC) model of the Miami Cancer Institute's IBA Proteus Plus system equipped with the DCS. Trimmer position, spot position, beam energy, and the presence or absence of a range shifter were all used as variables for the characterization of the model. The model was calibrated for pencil beam monitor unit calculations using procedures specified by International Atomic Energy Agency Technical Report Series 398 (IAEA TRS‐398). Results: The integral depth dose curves (IDDs) for energies between 70 MeV and 160 MeV among all simulated trimmer combinations, with and without the ranger shifter, agreed between PETRA and DCMC at the 1%/1 mm 1‐D gamma criteria for 99.99% of points. For lateral dose profiles, the median 2‐D gamma pass rate for all profiles at 1.5%/1.5 mm was 99.99% at the water phantom surface, plateau, and Bragg peak depths without the range shifter and at the surface and Bragg peak depths with the range shifter. The minimum 1.5%/1.5 mm gamma pass rates for the 2‐D profiles at the water phantom surface without and with the range shifter were 98.02% and 97.91%, respectively, and, at the Bragg peak, the minimum pass rates were 97.80% and 97.5%, respectively. Conclusion: The PETRA model for DCS dose calculations was successfully defined and benchmarked for use in a commercially available TPS. [ABSTRACT FROM AUTHOR]

Purposefulness may facilitate self‐regulation; however, little is known about the self‐regulatory strategies that are implemented by purposeful individuals. Given the multiple regulatory challenges students face in their social and academic lives, a central aim of the current work was to consider how purposefulness and self‐regulation are linked during the first semester of university. This 13‐week‐long study was conducted with first‐semester college students (N = 256) in the United States of America to examine whether weekly fluctuations in purposefulness may be connected to the use of traditionally adaptive (problem‐solving) and maladaptive (rumination and experiential avoidance) self‐regulation strategies. Consistent with our hypothesis, at the within‐ and between‐person level, higher purposefulness was associated with greater use of problem‐solving, lower rumination, and lower experiential avoidance at the weekly level. The findings imply purposefulness is an important individual difference that may explain better or worse self‐regulatory abilities. [ABSTRACT FROM AUTHOR]

Introduction: This 33‐year study examined associations between self‐control development in adolescence and forgivingness, i.e., the dispositional tendency to forgive others, in middle adulthood. Methods: Participants were 1350 adults aged 45 years (50.6% female). Self‐control was measured yearly from age 12 to 16, while forgivingness was measured at age 45. Results: Results indicated significant individual differences in level and change of self‐control across the adolescent years and an average mean‐level increase. Individual differences in level and change in self‐control were independently associated with forgivingness in middle adulthood. Individuals who either entered adolescence with higher self‐control, and/or increased in self‐control during the adolescent years, reported higher scores in forgivingness at age 45 compared to peers. This pattern held even after controlling for gender, socioeconomic status (SES), and conduct problems in adolescence. Conclusion: The current findings demonstrate that developmental processes in adolescence are important for individual differences in the dispositional tendency to forgive others in adulthood. [ABSTRACT FROM AUTHOR]

The rapid recovery of meteorites mitigates the exposure of astromaterials to the terrestrial environment and subsequent contamination. Modern fireball observatories have enabled the more accurate triangulation of fireball trajectories, which has aided in the location of strewn fields, in the case of meteorite‐producing events. Despite this advancement, most meteorite searches still use manual searching to locate any meteorite falls, which is often labor‐intensive and has a slow coverage rate (km2 day−1). Recent work has begun exploring the application of drone technology to the recovery of meteorites; however, most of this work has focused on falls in arid environments. Our study examines the utilization of drones with thermal imaging technology to aid in the recovery of meteorites that have fallen on a snow‐covered field. We created a simulated strewn field that included meteorite specimens as well as Earth rocks with similar properties ("meteowrongs"). Thermal imagery was utilized to determine whether the thermal contrast between meteorites and snow could aid in the identification of meteorites. We found that the thermal contrast was significant enough that meteorites were readily identifiable within thermal images; however, it was not significant enough to distinguish between the meteorites and the meteowrongs. The utilization of thermal imagery in conjunction with visible imagery has the potential to aid in the rapid recovery of meteorites in snow‐covered landscapes. [ABSTRACT FROM AUTHOR]

Activism is responsible for many of the positive social changes we have seen across time, and is central to pushing for continued social change. However, these positive outcomes do not come without a cost, as activism can also be draining and can lead to physical and emotional harm for those involved. Social policies and intervention programs have addressed how to help people maintain their engagement with activism aims, though few have considered the motivational role of purpose in life. As purpose in life involves a sustained commitment to one's goals, having a purpose in life centered around activism may help an individual remain committed to activism and to the creation of change in the face of these obstacles. If activist purpose can help us understand and predict who is likely to remain engaged in activism, then it is valuable to consider what factors influence the development of activist purpose, in order to continue necessary social change. Thus, in this work we define activist purpose, and theorize as to what factors may be relevant to the development of an activist purpose by situating predictors of activism and collective action within the literature on pathways to purpose in life. This work may thus provide a greater understanding of how to encourage activism or reduce the harmful effects associated with activism. [ABSTRACT FROM AUTHOR]

Organic matter in astromaterials can provide important information for understanding the chemistry of our solar system and the prebiotic conditions of the early Earth. However, once astromaterials reach the Earth's surface, they can be readily contaminated through contact with the Earth's surface as well as during processing and curation. Here, we investigate how typical handling and curation materials interact with meteorite specimens by documenting hydrophobic organic compound contamination in the laboratory environment and on materials that might be used for their collection and storage. We use gas chromatography–mass spectrometry analysis of soluble organic compounds in dichloromethane extracts of these materials to gain insights into what materials and methods are best for the collection and curation of astromaterials. Our results have implications for how extraterrestrial samples—especially those containing significant intrinsic organic matter—are handled and curated to preserve them in their most pristine states. Following recommendations of other researchers in the area of returned sample curation, we advocate for a thorough investigation into the materials used in handling and curation of meteorites to create a contamination baseline to inform soluble organic analyses on astromaterials and enable the discrimination of terrestrial and extraterrestrial compounds. [ABSTRACT FROM AUTHOR]

Introduction: Cori Bush is a prominent modern activist in the U.S., becoming involved in activism following Michael Brown's death. Bush, like many activists before her, has set clear goals for social change, yet work is needed to understand why Bush (and like others) became an activist when others did not. One potential reason may be that these exemplars found purpose in life in activism. Thus, the current psychobiography explores the purpose in life of Cori Bush, a prominent activist and politician in the U.S., as well as what factors emerge for how Bush found her purpose in life. Method: The present research gathered public materials (e.g., speeches) from Bush and coded materials for the presence and depth of both themes of purpose and factors predicting purpose. Results: Activism was the most prominent theme of purpose for Bush, with some pro‐social purposes also occurring. Multiple personal factors emerged as influences on her activist purpose, including extraversion, psychological flexibility, and action‐oriented coping style. Additionally, the situational factors of discriminatory experiences and Michael Brown's death emerged as factors. Conclusion: These results suggest that Bush has an activist purpose in life and that she found this purpose through a combination of personal and situational factors. [ABSTRACT FROM AUTHOR]

Sense of purpose, or feeling that one has personally meaningful goals and directions guiding them through life, consistently predicts a variety of desirable well‐being, health, and social outcomes. However, work has been limited with respect to evaluating it as a predictor and promoter of romantic relationships or how purpose may develop in these contexts. For instance, healthy romantic relationships could also help individuals develop and maintain a higher sense of purpose. With cross‐sectional evidence finding positive associations between sense of purpose and romantic relationship commitment and satisfaction, the current study expanded on past work by using longitudinal data with three months between two measurement occasions (Time 1: N = 2243; Time 2: N = 1284) to evaluate whether sense of purpose predicted relationship status over time and how changes in relationship quality and sense of purpose were associated. Results showed that a greater sense of purpose predicted maintaining a romantic relationship but did not predict later romantic relationship quality, although higher romantic relationship quality predicted an increase in sense of purpose. Findings are discussed regarding why people with a higher sense of purpose may be more likely to stay in relationships as well as the role that positive romantic relationships may play in helping maintain a higher sense of purpose. [ABSTRACT FROM AUTHOR]

Background: Given the gendering of engineering roles and competencies, the evidence that the skills required for engineering management are widely referred to as social, and the fact that men engineers are stereotyped as more technical, and women as more social, it might be theorized that (a) those that occupy managerial (vs. technical) roles in engineering are more socially oriented, and (b) that this will especially be the case for women. However, no research has empirically tested the relationship between having socially oriented characteristics and being in managerial roles within the engineering profession, nor have gender differences been examined. Purpose: We test whether social interests and communal goal strivings are linked to engineers' positioning in managerial roles and explore gender as a moderator of these relationships. Additionally, because enterprising interests and agentic goal strivings have been linked to managerial roles in other occupations, we test these as additional predictors of engineers' positioning in managerial roles. Method: In a field survey of 274 industry engineers from multiple organizations and subfields, we tested the relationships described using hierarchical linear regression analysis. Results: Enterprising interests and agentic goals, but not social interests and communal goals, were associated with being in managerial roles, and there were no gender differences in these relationships. Conclusions: Our findings challenge perceptions that managerial roles in engineering, and particularly women's positioning in these roles, are associated with socially oriented tendencies. Findings have implications for research on gender stereotyping and intraoccupational gender segregation in engineering and hold educational implications for curriculum, instruction, and advising. [ABSTRACT FROM AUTHOR]

Studying organic compounds in meteorites provides important insight into the chemical processes that occurred in the early solar system. Once meteorites reach the Earth's surface, they are subject to terrestrial organic contamination that may confound the conclusions that we draw from meteorite organic analyses. Within this study, specimens of the Tarda C2 ungrouped carbonaceous chondrite, collected within a few days of its fall on August 25, 2020, from a barren desert in Morocco, were analyzed for their organic compound contents. In addition, a sand sample from the strewn field was analyzed to confirm the sources of a handful of contaminating compounds detected in the Tarda stones. Using dichloromethane (DCM) rinses of the Tarda stone exteriors and DCM and hot water extractions of meteorite specimen powders and sand sample, and analysis of the soluble organics by gas chromatography‐mass spectrometry, we distinguish between extraterrestrial and contaminant sources for each organic compound. In this study, N‐tert‐butyldimethylsilyl‐N‐methyltrifluoroacetamide (MTBSTFA) was used to derivatize the hot water extractions to utilize its single‐step derivatization reaction ability. The compounds determined to be intrinsic to Tarda include propanoic acid, propanedioic acid, butanedioic acid, fumaric acid, methylmaleic acid, threonine, proline, glycine, urea, and cyclic octaatomic sulfur. We detected numerous terrestrial organic compounds, all of which were traced back to the meteorites' collection area, with several being confirmed in the sand sample. Our results have implications for best practices for the collection of freshly fallen meteorites, especially carbonaceous chondrites, as well as how specimens should be handled and curated after collection. [ABSTRACT FROM AUTHOR]

Soluble organic matter analyses of astromaterials can provide valuable information on the chemistry of our solar system and the processes that occur within it. The surface of the Earth, however, is a significant source of organic compounds due to the presence of life; this environment represents a major source of potential contamination for recently fallen meteorites. Here, we analyze select stones of the CM2 Aguas Zarcas carbonaceous chondrite, which fell on April 23, 2019, in Aguas Zarcas, San Carlos county, Alajuela province, Costa Rica, with the goal of determining the complement of intrinsic and contaminant soluble organic matter. The specimens were collected pre‐ and post‐rainfall, days to weeks after the stones fell on the Earth. Through gas chromatography‐mass spectrometry analysis of soluble organic matter in dichloromethane and hot water extracts of meteorite powders, we differentiate between extraterrestrial and contaminant sources for each organic compound detected. In this study, N‐tert‐butyldimethylsilyl‐ N‐methyltrifluoroacetamide (MTBSTFA) was used to derivatize the hot water extracts to test out its "one‐pot" extraction capabilities. The majority of the detectable organic compounds are contaminants and can be explained as being sourced from the terrestrial surface onto which the meteorite fell. Our results have implications for how environmental factors, such as land use and rainfall events in this case, can impact the intrinsic organics in carbonaceous chondrites. [ABSTRACT FROM AUTHOR]

Purpose: The radiobiological benefits afforded by spatially fractionated (GRID) radiation therapy pairs well with the dosimetric advantages of proton therapy. Inspired by the emergence of energy‐layer specific collimators in pencil beam scanning (PBS), this work investigates how the spot spacing and collimation can be optimized to maximize the therapeutic gains of a GRID treatment while demonstrating the integration of a dynamic collimation system (DCS) within a commercial beamline to deliver GRID treatments and experimentally benchmark Monte Carlo calculation methods. Methods: GRID profiles were experimentally benchmarked using a clinical DCS prototype that was mounted to the nozzle of the IBA‐dedicated nozzle system. Integral depth dose (IDD) curves and lateral profiles were measured for uncollimated and GRID‐collimated beamlets. A library of collimated GRID dose distributions were simulated by placing beamlets within a specified uniform grid and weighting the beamlets to achieve a volume‐averaged tumor cell survival equivalent to an open field delivery. The healthy tissue sparing afforded by the GRID distribution was then estimated across a range of spot spacings and collimation widths, which were later optimized based on the radiosensitivity of the tumor cell line and the nominal spot size of the PBS system. This was accomplished by using validated models of the IBA universal and dedicated nozzles. Results: Excellent agreement was observed between the measured and simulated profiles. The IDDs matched above 98.7% when analyzed using a 1%/1‐mm gamma criterion with some minor deviation observed near the Bragg peak for higher beamlet energies. Lateral profile distributions predicted using Monte Carlo methods agreed well with the measured profiles; a gamma passing rate of 95% or higher was observed for all in‐depth profiles examined using a 3%/2‐mm criteria. Additional collimation was shown to improve PBS GRID treatments by sharpening the lateral penumbra of the beamlets but creates a trade‐off between enhancing the valley‐to‐peak ratio of the GRID delivery and the dose‐volume effect. The optimal collimation width and spot spacing changed as a function of the tumor cell radiosensitivity, dose, and spot size. In general, a spot spacing below 2.0 cm with a collimation less than 1.0 cm provided a superior dose distribution among the specific cases studied. Conclusions: The ability to customize a GRID dose distribution using different collimation sizes and spot spacings is a useful advantage, especially to maximize the overall therapeutic benefit. In this regard, the capabilities of the DCS, and perhaps alternative dynamic collimators, can be used to enhance GRID treatments. Physical dose models calculated using Monte Carlo methods were experimentally benchmarked in water and were found to accurately predict the respective dose distributions of uncollimated and DCS‐collimated GRID profiles. [ABSTRACT FROM AUTHOR]

Objective: To examine the major sources of vitamin D [25‐hydroxyvitamin D (25(OH)D)] and evaluate their collective role on rates of vitamin D deficiency/insufficiency among older adults. Methods: Cross‐sectional analysis of the relationship between serum 25(OH)D levels and sources of vitamin D (self‐reported and objectively validated sun exposure, supplementation, food including fortified sources). Study subjects were part of the Hawaii Longitudinal Study of Personality and Health who completed a clinic visit between 55 and 65 years (M = 59.6) and food frequency questionnaire, and provided serum to assay 25(OH)D (n = 223). Results: Although mean serum 25(OH)D levels were overall sufficient (34.3 ng/ml, [SD = 10.9]), over one‐third of participants (38%) had vitamin D deficiency/insufficiency (<30 ng/ml). Asians were the most likely to be insufficient and Filipinos were the least likely (43% vs. 11%, respectively). Overall, supplement use and sun exposure were both associated with higher 25(OH)D levels and lower risk of vitamin D deficiency/insufficiency. Moreover, Vitamin D sources varied by race/ethnic groups. In multivariate models, higher body mass index, being Asian or Native Hawaiian/Pacific Islander, low supplement use, and low sun exposure were associated with higher risk for vitamin D deficiency/insufficiency (<30 ng/ml). Conclusions: Over 1/3 of the older adult sample was vitamin D deficient/insufficient, despite most of the participants living in a tropical climate with year‐round access to sun as a vitamin D source. Sun exposure and supplement use, but not food intake, explained differences in vitamin D deficiency/insufficiency in this population. [ABSTRACT FROM AUTHOR]

Background: To define the location of the initial contralateral lymph node (LN) metastasis in patients with oropharynx cancer. Methods: The location of the LN centroids from patients with oropharynx cancer and a single radiographically positive contralateral LN was defined. A clinical target volume (CTV) inclusive of all LN centroids was created, and its impact on dose to organs at risk was assessed. Results: We identified 55 patients of which 49/55 had a single contralateral LN in level IIA, 4/55 in level III, 1/55 in level IIB, and 1/55 in the retropharynx. Mean radiation dose to the contralateral parotid gland was 15.1 and 21.0 Gy, (p <0.001) using the modeled high‐risk elective CTV and a consensus CTV, respectively. Conclusions: We present a systematic approach for identifying the contralateral nodal regions at highest risk of harboring subclinical disease in patients with oropharynx cancer that warrants prospective clinical study. [ABSTRACT FROM AUTHOR]

A core attribute of the positive youth development movement has been to nullify negative perceptions of youth's capacities. Toward this end, measurement and classification systems benefit from efforts to view youth's capacities as assets contextualized by developmental potentials and opportunities. In this article, we consider this point with respect to whether youth are purposeful. The prevailing sentiment of some researchers holds that few adolescents have a purpose in life, perhaps reifying negative beliefs about their capacity. We assert an alternative view that focuses on sense of purpose, which relies on abundant evidence that adolescents generally perceive themselves to be purposeful, thus offering a more inclusive and positive portrayal of young people. This different perspective also opens the door to new opportunities for studying the development of purpose among marginalized adolescents, as well as how interventions may motivate a sense of purpose among youth. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this work was to develop and experimentally validate a Dynamic Collimation Monte Carlo (DCMC) simulation package specifically designed for the simulation of collimators in pencil beam scanning proton therapy (PBS‐PT). The DCMC package was developed using the TOPAS Monte Carlo platform and consists of a generalized PBS source model and collimator component extensions. Methods: A divergent point‐source model of the IBA dedicated nozzle (DN) at the Miami Cancer Institute (MCI) was created and validated against on‐axis commissioning measurements taken at MCI. The beamline optics were mathematically incorporated into the source to model beamlet deflections in the X and Y directions at the respective magnet planes. Off‐axis measurements taken at multiple planes in air were used to validate both the off‐axis spot size and divergence of the source model. The DCS trimmers were modeled and incorporated as TOPAS geometry extensions that linearly translate and rotate about the bending magnets. To validate the collimator model, a series of integral depth dose (IDD) and lateral profile measurements were acquired at MCI and used to benchmark the DCMC performance for modeling both pristine and range shifted beamlets. The water equivalent thickness (WET) of the range shifter was determined by quantifying the shift in the depth of the 80% dose point distal to the Bragg peak between the range shifted and pristine uncollimated beams. Results: A source model of the IBA DN system was successfully commissioned against on‐ and off‐axis IDD and lateral profile measurements performed at MCI. The divergence of the source model was matched through an optimization of the source‐to‐axis distance and comparison against in‐air spot profiles. The DCS model was then benchmarked against collimated IDD and in‐air and in‐phantom lateral profile measurements. Gamma analysis was used to evaluate the agreement between measured and simulated lateral profiles and IDDs with 1%/1 mm criteria and a 1% dose threshold. For the pristine collimated beams, the average 1%/1 mm gamma pass rates across all collimator configurations investigated were 99.8% for IDDs and 97.6% and 95.2% for in‐air and in‐phantom lateral profiles. All range shifted collimated IDDs passed at 100% while in‐air and in‐phantom lateral profiles had average pass rates of 99.1% and 99.8%, respectively. The measured and simulated WET of the polyethylene range shifter was determined to be 40.9 and 41.0 mm, respectively. Conclusions: We have developed a TOPAS‐based Monte Carlo package for modeling collimators in PBS‐PT. This package was then commissioned to model the IBA DN system and DCS located at MCI using both uncollimated and collimated measurements. Validation results demonstrate that the DCMC package can be used to accurately model other aspects of a DCS implementation via simulation. [ABSTRACT FROM AUTHOR]

Objective: Employment appears to influence employees' sense of purpose, insofar as work roles can provide life direction and allow individuals to fulfill meaningful aims or have regular goal‐related activity engagement. However, research is needed on which specific characteristics of the work predict employees' sense of purpose. The current study sought to quantitate the degree to which specific work characteristics, including skill variety, autonomy, coworker support, and supervisor support, were associated with initial levels and changes in purpose. Additionally, we examine positive and negative work‐home spillover as moderators of these relationships. Methods: We examined hypothesized relationships in a subsample (N = 4,963) of a nationally representative panel study which included between two and three assessments of work characteristics, spillover, and sense of purpose, each roughly 10 years apart. Results: Using multilevel models to assess within‐person associations and lagged effects, we found that greater skill variety and coworker support but not autonomy or supervisor support, were associated with higher levels of purpose. Moreover, increases in purpose were associated with higher initial levels of skill variety. These relationships were not moderated by spillover. Conclusion: Individuals with skill variety and coworker support at work appear to experience the strongest levels of sense of purpose. [ABSTRACT FROM AUTHOR]

Background: With no known cure for Alzheimer's disease and related dementias, delaying the onset of cognitive decline represents a key target for future dementia research. Sense of purpose has been shown to be associated with high cognitive functioning, more supportive social ties, and greater intellectual activity, and may be valuable for mitigating cognitive impairment both before and following its onset. Method: Longitudinal data from the Health and Retirement Study (HRS, n = 10,542) and the Rush Memory and Aging Project (MAP, n = 10.48) were used to examine associations between sense of purpose and prospective transitions across normal cognition, mild cognitive impairment (MCI), dementia, and death over up to 12 and 19 years, respectively. Multistate survival modeling examined the impact of sense of purpose on risk for each transition, adjusting for age, sex, education, apolipoprotein‐E allele, and depressive symptoms. Multinomial regression was used to estimate life expectancy in each cognitive state. Result: More purposeful older adults were found to have lower prospective risk of developing MCI in the HRS (HR = 0.93, 95% CI: 0.90, 0.97) and MAP (HR = 0.82, 95% CI: 0.69, 0.98) and had increased likelihood of improvement in cognitive functioning following MCI classification. In both samples, those higher in sense of purpose were found to have significantly longer overall life expectancy and life expectancy free of cognitive impairment (without MCI or dementia). Conclusion: Older adults higher in sense of purpose appear to live longer lives, with these differences in life expectancy attributable to increases in years lived without cognitive impairment. Replication of findings across longitudinal studies with disparate samples and measurement procedures provides robust support that having a strong sense of purpose in life contributes to cognitive reserve and resilience. Interventions aiming to promote older adult sense of purpose could extend the cognitive healthspan—the period in which individuals live in a cognitively healthy state free of impairment. [ABSTRACT FROM AUTHOR]

Objective: We evaluated the role of natural disaster adversity on personality development in the wake of a hurricane, and the moderating role of previous hurricane exposure. Method: We used a two‐wave longitudinal design and a diverse sample of emerging adults (n = 691; mean age = 22 years; 72% females, 27% European American, 29% Latino, 23% Asian American, 15% African American, 6% Multiracial/Other) who were exposed to one of the most damaging hurricanes on record, though to differing degrees. Immediately after the hurricane, we assessed objective individual‐level hurricane exposure, previous exposure to hurricanes, demographics, socioeconomic status, and Big Five personality traits. One year later, we re‐assessed Big Five personality traits. Results: Using latent change models, we found significant individual differences both in participants' initial levels of personality traits at baseline, as well as in their developmental patterns of change in the year following the hurricane. However, there was no evidence of mean‐level change. Moreover, neither hurricane exposure level, nor its interaction with previous exposure showed statistically significant associations with the rates of change in any personality trait. Conclusions: The present findings support a stability account, whereby individuals largely maintain their personality dispositions following an adverse life event, in this case a hurricane. [ABSTRACT FROM AUTHOR]

Objective: As video chatting has emerged as a leading form of communication for work, education, and socialization during the COVID‐19 pandemic, it is important to investigate the association between video chatting and appearance satisfaction. Method: Participants included women from the United States (n = 438; age: M = 31.3, SD = 12.71) who completed measures examining their use of video chatting services, self‐objectification, video chatting appearance comparison, and appearance satisfaction. Results: The total time spent on video chatting services was not associated with appearance satisfaction; however, self‐objectification moderated the relationship between total hours of video chatting and appearance satisfaction. In addition, participants who engaged in more video chatting appearance comparisons reported lower face and body satisfaction. Furthermore, video chatting appearance comparison was associated with more frequent usage of certain Zoom features, such as the "touch up my appearance" feature, and more time spent looking at oneself on video calls. Finally, those who spent more time engaged with their families over video chatting services reported greater face and body satisfaction. Discussion The results of the current study demonstrate that time spent video chatting is not predictive of appearance satisfaction, but that self‐objectification can exacerbate these associations. [ABSTRACT FROM AUTHOR]

Objective: Future time perspective (FTP) refers to individuals' perceptions of the future as either open-ended or limited. Despite well-documented individual differences in FTP across the adult life span, little is known about short-term variations of FTP within individuals and the within-person associations between FTP and affective experiences.Method: Study 1 used data from a daily diary study over 10 days (N = 564) with a wide age range across the adult life span (M = 48.30). Study 2 used data from an ambulatory assessment study over 10 days (N = 136) obtained from healthy older adults (M = 70.45).Results: Findings suggest that 10% to 20% of the total variance in FTP was within-person and 29% to 62% of the total variance in affect was within-person. Multilevel modeling showed that occasions with a more open-ended FTP were occasions with more positive affect, energetic arousal, calmness, and positive valence, and less negative affect. Age moderated the within-person associations between FTP and positive and negative affect as well as energetic arousal, with weaker associations for older adults.Conclusions: This research demonstrates the importance of looking at both within-person and between-person differences with respect to the associations between FTP and affective experiences in daily life. [ABSTRACT FROM AUTHOR]

Intrafraction imaging‐based motion management systems for external beam radiotherapy can rely on internal surrogate structures when the target is not easily visualized. This work evaluated the validity of using liver vessels as internal surrogates for the estimation of liver tumor motion. Vessel and tumor motion were assessed using ten two‐dimensional sagittal MR cine datasets collected on the ViewRay MRIdian. For each case, a liver tumor and at least one vessel were tracked for 175 s. A tracking approach utilizing block matching and multiple simultaneous templates was applied. Accuracy of the tracked motion was calculated from the error between the tracked centroid position and manually defined ground truth annotations. The patient's abdomen surface and diaphragm were manually annotated in all frames. The Pearson correlation coefficient (CC) was used to compare the motion of the features and tumor in the anterior–posterior (AP) and superior–inferior (SI) directions. The distance between the centroids of the features and the tumors was calculated to assess if feature proximity affects relative correlation, and the tumor range of motion was determined. Intra‐ and interfraction motion amplitude variabilities were evaluated to further assess the relationship between tumor and feature motion. The mean CC between the motion of the vessel and the tumor were 0.85 ± 0.11 (AP) and 0.92 ± 0.04 (SI), 0.83 ± 0.11 (AP) and −0.89 ± 0.06 (SI) for the surface and tumor, and 0.80 ± 0.17 (AP) and 0.94 ± 0.03 (SI) for the diaphragm and tumor. For intrafraction analysis, the average amplitude variability was 2.47 ± 0.77 mm (AP) and 3.14 ± 1.49 mm (SI) for the vessels, 2.70 ± 1.08 mm (AP) and 3.43 ± 1.73 mm (SI) for the surface, and 2.76 ± 1.41 mm (AP) and 2.91 ± 1.38 mm (SI) for the diaphragm. No relationship between distance and motion correlation was observed. The motion of liver tumors and liver vessels was well correlated, making vessels a suitable surrogate for tumor motion in the liver. [ABSTRACT FROM AUTHOR]

Purpose: When designing a collimation system for pencil beam spot scanning proton therapy, a decision must be made whether or not to rotate, or focus, the collimator to match beamlet deflection as a function of off‐axis distance. If the collimator is not focused, the beamlet shape and fluence will vary as a function of off‐axis distance due to partial transmission through the collimator. In this work, we quantify the magnitude of these effects and propose a focused dynamic collimation system (DCS) for use in proton therapy spot scanning. Methods: This study was done in silico using a model of the Miami Cancer Institute's (MCI) IBA Proteus Plus system created in Geant4‐based TOPAS. The DCS utilizes rectangular nickel trimmers mounted on rotating sliders that move in synchrony with the pencil beam to provide focused collimation at the edge of the target. Using a simplified setup of the DCS, simulations were performed at various off‐axis locations corresponding to beam deflection angles ranging from 0° to 2.5°. At each off‐axis location, focused (trimmer rotated) and unfocused (trimmer not rotated) simulations were performed. In all simulations, a 4 cm water equivalent thickness range shifter was placed upstream of the collimator, and a voxelized water phantom that scored dose was placed downstream, each with 4 cm airgaps. Results: Increasing the beam deflection angle for an unfocused trimmer caused the collimated edge of the beamlet profile to shift 0.08–0.61 mm from the baseline 0° simulation. There was also an increase in low‐dose regions on the collimated edge ranging from 14.6% to 192.4%. Lastly, the maximum dose, Dmax, was 0–5% higher for the unfocused simulations. With a focused trimmer design, the profile shift and dose increases were all eliminated. Conclusions: We have shown that focusing a collimator in spot scanning proton therapy reduces dose at the collimated edge compared to conventional, unfocused collimation devices and presented a simple, mechanical design for achieving focusing for a range of source‐to‐collimator distances. [ABSTRACT FROM AUTHOR]

Objective: Gratitude plays an important role in individual and social well-being. However, less is known about the link between gratitude and experiences of interpersonal stressors. The current research examined the associations between gratitude and interpersonal transgressions.Method: One cross-sectional study with a broad age range and two daily diary studies (total N = 2,348; total age range: 18-91) were used to test the associations on the between- and within-person level.Results: A consistent result across all studies was that dispositionally grateful individuals tended to report fewer interpersonal transgressions than less grateful people. In turn, people who generally reported more interpersonal transgressions were less grateful in daily life. Moreover, higher gratitude on one specific day was associated with fewer reported transgressions on the same day. However, the results from the daily diary studies indicated differences between the samples. Whereas gratitude was consistently associated with interpersonal transgressions in one daily diary sample, the findings in the second daily diary sample were less consistent.Conclusion: The present findings suggest that grateful people tend to perceive their social exchanges differently and/or actually experience fewer interpersonal transgressions. Future work is needed to test the underlying mechanisms of this negative association. [ABSTRACT FROM AUTHOR]

By analyzing impact glass, the evolution of the impact melt at the Mistastin Lake impact structure was investigated. Impact glass clasts are present in a range of impactites, including polymict breccias and clast‐rich impact melt rock, and from a variety of settings within the crater. From the glass clasts analyzed, three petrographic subtypes of impact glass were identified based on their clast content, prevalence of schlieren, color, texture, and habit. Several alteration phases were also observed replacing glass and infilling vesicles; however, textural observations and quantified compositional data allowed for the identification of pristine impact glass. Although the various types of glasses show significant overlap in their major oxide composition, several subtle variations in the major oxide chemistry of the glass were observed. To investigate this variation, a least‐squares mixing model was implemented utilizing the composition of the glass and the known target rock chemistry to model the initial melt composition. Additionally, image analysis of the glass clasts was used to investigate whether the compositional variations correlated to textural difference in the lithologies. We propose that the textural and compositional dichotomy observed is a product of the evolution, assimilation, and emplacement of the glass. The dichotomy is reflective of the melt either being ballistically emplaced (group 2 glasses: occurring in melt‐poor polymict breccias at lowermost stratigraphic position outside the transient crater) or the result of late‐stage melt flows (group 1 glasses, occurring in melt‐bearing polymict breccias and impact melt rocks at higher stratigraphic positions outside the transient crater). [ABSTRACT FROM AUTHOR]

We present a procedure for the determination of the isotopic ratios of silicon and oxygen from the same aliquot of anhydrous silicate material. The sample is placed in a bromine pentafluoride atmosphere as it is heated with a CO2 laser system releasing silicon tetrafluoride and oxygen gasses. The oxygen gas is then purified to remove other reaction by‐products through several liquid nitrogen traps before being captured onto a molecular sieve and transferred to an isotope ratio mass spectrometer. The silicon tetrafluoride gas is then purified using a supplementary line by repeatedly freezing to −196°C with liquid nitrogen and then thawing with an ethanol slurry at −110°C through a series of metal and Pyrex traps. The purified gas is then condensed into a Pyrex sample tube before it is transferred to an isotope ratio mass spectrometer for silicon isotope ratio measurements. This system has silicon yields of greater than 90% for pure quartz, olivine, and garnet standards and has a reproducibility of ±0.1‰ (2σ) for pure quartz for both oxygen and silicon isotope measurements. Meteoritic samples were also successfully analyzed to demonstrate this system's ability to measure the isotopic ratio composition of bulk powders with precision. This unique technique allows for the fluorination of planetary material without the need for wet chemistry. Though designed to analyze small aliquots of meteoritic material (1.5 to 3 mg), this approach can also be used to investigate refractory terrestrial samples where traditional fluorination is not suitable. [ABSTRACT FROM AUTHOR]

Dispositional characteristics are associated with important life outcomes across the lifespan, often predicting those outcomes decades in advance. Evidence demonstrates that personality characteristics measured during childhood and adolescence uniquely affect later life outcomes above and beyond adult personality. Currently, it is unclear why personality produces unique effects at different life stages, given the modest consistency of personality across the lifespan. In this article, we offer possible explanations for why these unique predictive effects may occur, charting pathways that link childhood personality to later outcomes that differ from how adult personality influences the same products. We conclude by suggesting directions for longitudinal investigations into when, why, and how assessments of childhood personality can help advance our understanding of lifespan development. [ABSTRACT FROM AUTHOR]

The Dhofar 1673, Dhofar 1983, and Dhofar 1984 meteorites are three lunar regolith breccias classified based on their petrography, mineralogy, oxygen isotopes, and bulk chemistry. All three meteorites are dominated by feldspathic lithic clasts; however, impact melt rock clasts and spherules are also found in each meteorite. The bulk chemistry of these samples is similar to other feldspathic highland meteorites with the Al2O3 content only slightly lower than average. Within the lithic clasts, the Mg # of mafic phases versus the anorthite content of feldspars is similar to other highland meteorites and is found to plot intermediate of the ferroan‐anorthositic suite and magnesian suite. The samples lack any KREEPy signature and have only minor indications of a mare basalt component, suggesting that the source region of all three meteorites would have been distal from the Procellarum KREEP Terrane and could have possibly been the Feldspathic Highland Terrane. All three meteorites were found within 500 m of each other in the Dhofar region of Oman. This, together with their similar petrography, stable isotope chemistry, and geochemistry indicates the possibility of a pairing. [ABSTRACT FROM AUTHOR]

The dosimetric stability of six TomoTherapy units was analyzed to investigate changes in performance over time and with system upgrades. Energy and output were tracked using monitor chamber signal, onboard megavoltage computed tomography (MVCT) detector profile, and external ion chamber measurements. The systems (and monitoring periods) include three Hi-Art (67, 61, and 65 mos.), two TomoHDA (31 and 26 mos.), and one Radixact unit (11 mos.), representing approximately 10 years of clinical use. The four newest systems use the Dose Control Stability (DCS) system and Fixed Target Linear Accelerator (linac) (FTL). The output stability is reported as deviation from reference monitor chamber signal for all systems and/or from an external chamber signal. The energy stability was monitored using relative (center versus off-axis) MVCT detector signal (beam profile) and/or the ratio of chamber measurements at 2 depths. The clinical TomoHDA data were used to benchmark the Radixact stability, which has the same FTL but runs at a higher dose rate. The output based on monitor chamber data of all systems is very stable. The standard deviation of daily output on the non-DCS systems was 0.94-1.52%. As expected, the DCS systems had improved standard deviation: 0.004-0.06%. The beam energy was also very stable for all units. The standard deviation in profile flatness was 0.23-0.62% for rotating target systems and 0.04-0.09% for FTL. Ion chamber output and PDD ratios supported these results. The output stability on the Radixact system during extended treatment delivery (20, 30, and 40 min) was comparable to a clinical TomoHDA system. For each system, results are consistent between different measurement tools and techniques, proving not only the dosimetric stability, but also these quality parameters can be confirmed with various metrics. The replacement history over extended time periods of the major dosimetric components of the different delivery systems (target, linac, and magnetron) is also reported. [ABSTRACT FROM AUTHOR]

Though it is frequently assumed that the college experience can influence our life goals, this claim has been relatively understudied. The current study examined the role of goals in college major selection, as well as whether major selection influences later goal change. In addition, we examined whether a person's perceptions of his or her peers' goals influence goal setting. Using a sample of German students (Mage  = 19 years; n = 3,023 at Wave 1), we assessed life goal levels and changes from high school into college across three assessment occasions. Participants reported their current aspirations, along with the perceived goals of their peers during the college assessments. Using latent growth curve models, findings suggest that life goals upon entering college significantly predict the majors students select. However, this major selection had limited influence on later changes in life goals. Stronger effects were found with respect to perceptions of peers' goals, with students tending to change their goals to better align with their peers. The current study provides evidence that life goals are relatively stable and yet can change during the emerging adult years, in ways that demonstrate the potential influence of the college experience. [ABSTRACT FROM AUTHOR]

Are there age differences in gratitude from early adulthood to old age? The current studies tested several ways by which an association between age and dispositional gratitude may present, by considering multiple measures on both fronts. We used data from three cross-sectional studies (total N = 1,736; total age range: 19-94). The results indicated that (a) age effects in gratitude are more likely to occur for subjective age in terms of future time perspective (i.e., people's perceptions of their remaining opportunities and time) than chronological age; (b) chronological age effects are more domain specific than general in nature; and (c) they are more likely to occur for the instrumental domain as compared to the interpersonal domain. Finally, the results indicated that (d) perceived future time, particularly with respect to remaining opportunities, mediates the relation between chronological age and general gratitude. Overall, the findings suggest that gratitude is subject to a variety of developmental influences across adulthood. [ABSTRACT FROM AUTHOR]

B acillus subtilis and its closest relatives have multiple rap-phr quorum sensing gene pairs that coordinate a variety of physiological processes with population density. Extra-chromosomal rap-phr genes are also present on mobile genetic elements, yet relatively little is known about their function. In this work, we demonstrate that Rap60- Phr60 from plasmid pTA1060 coordinates a variety of biological processes with population density including sporulation, cannibalism, biofilm formation and genetic competence. Similar to other Rap proteins that control sporulation, Rap60 modulates phosphorylation of the transcription factor Spo0 A by acting as a phosphatase of Spo0 F∼ P, an intermediate of the sporulation phosphorelay system. Additionally, Rap60 plays a noncanonical role in regulating the autophosphorylation of the sporulation-specific kinase KinA, a novel activity for Rap proteins. In contrast, Rap proteins that modulate genetic competence interfere with DNA binding by the transcription factor ComA. Rap60 regulates the activity of ComA in a unique manner by forming a Rap60- ComA- DNA ternary complex that inhibits transcription of target genes. Taken together, this work provides new insight into two novel mechanisms of regulating Spo0 A and ComA by Rap60 and expands our general understanding of how plasmid-encoded quorum sensing pairs regulate important biological processes. [ABSTRACT FROM AUTHOR]

This study tested whether divorce helps explain individual differences in personality development in the years that follow a divorce. The sample consisted of 526 middle-aged adults aged 42-46 years at the beginning. Personality traits were measured using the NEO-Five-Factor Inventory at three measurement occasions over 12 years. First, personality development was characterized by individual differences in change. Second, those individuals who experienced a divorce showed a decrease in extraversion and positive affect over time although nondivorced individuals did not change on these traits. Third, divorce was associated with a decrease in dependability. Fourth, divorce was associated with a decrease in orderliness for individuals who were remarried. The results of this study indicated that divorce had little influence on personality development. [ABSTRACT FROM AUTHOR]

Purpose: To introduce a method to model the 3D dose distribution of laterally asymmetric proton beamlets resulting from collimation. The model enables rapid beamlet calculation for spot scanning (SS) delivery using a novel penumbra-reducing dynamic collimation system (DCS) with two pairs of trimmers oriented perpendicular to each other. Methods: Trimmed beamlet dose distributions in water were simulated with MCNPX and the collimating effects noted in the simulations were validated by experimental measurement. The simulated beamlets were modeled analytically using integral depth dose curves along with an asymmetric Gaussian function to represent fluence in the beam's eye view (BEV). The BEV parameters consisted of Gaussian standard deviations (sigmas) along each primary axis (<σx1 σx2σy1σy2) together with the spatial location of the maximum dose (μx, μy). Percent depth dose variation with trimmer position was accounted for with a depth-dependent correction function. Beamlet growth with depth was accounted for by combining the in-air divergence with Hong's fit of the Highland approximation along each axis in the BEV. Results: The beamlet model showed excellent agreement with the Monte Carlo simulation data used as a benchmark. The overall passing rate for a 3D gamma test with 3%/3 mm passing criteria was 96.1% between the analytical model and Monte Carlo data in an example treatment plan. Conclusions: The analytical model is capable of accurately representing individual asymmetric beamlets resulting from use of the DCS. This method enables integration of the DCS into a treatment planning system to perform dose computation in patient datasets. The method could be generalized for use with any SS collimation system in which blades, leaves, or trimmers are used to laterally sharpen beamlets. [ABSTRACT FROM AUTHOR]

The benefits of living a conscientious life have been demonstrated across multiple domains, and yet, few studies have sought to explain how the positive effects in one area may help explain those in another. The current article considers the possibility that conscientious individuals live healthier lives by virtue of having greater success in their relationships. Using both past research and new findings to support our model, we set forth a framework by which to consider how Conscientiousness affects relationship functioning, which in turn leads to better physical, emotional, and psychological health. In so doing, we also provide a new outlook on the health benefits associated with Conscientiousness, and how these may be conferred by relationship success. [ABSTRACT FROM AUTHOR]

Purpose: In the absence of a collimation system the lateral penumbra of spot scanning (SS) dose distributions delivered by low energy proton beams is highly dependent on the spot size. For current commercial equipment, spot size increases with decreasing proton energy thereby reducing the benefit of the SS technique. This paper presents a dynamic collimation system (DCS) for sharpening the lateral penumbra of proton therapy dose distributions delivered by SS. Methods: The collimation system presented here exploits the property that a proton pencil beam used for SS requires collimation only when it is near the target edge, enabling the use of trimmers that are in motion at times when the pencil beam is away from the target edge. The device consists of two pairs of parallel nickel trimmer blades of 2 cm thickness and dimensions of 2 cm x 18 cm in the beam's eye view. The two pairs of trimmer blades are rotated 90° relative to each other to form a rectangular shape. Each trimmer blade is capable of rapid motion in the direction perpendicular to the central beam axis by means of a linear motor, with maximum velocity and acceleration of 2.5 m/s and 19.6 m/s2, respectively. The blades travel on curved tracks to match the divergence of the proton source. An algorithm for selecting blade positions is developed to minimize the dose delivered outside of the target, and treatment plans are created both with and without the DCS Results: The snout of the DCS has outer dimensions of 22.6 × 22.6 cm² and is capable of delivering a minimum treatment field size of 15 × 15 cm². Using currently available components, the constructed system would weigh less than 20 kg. For irregularly shaped fields, the use of the DCS reduces the mean dose outside of a 2D target of 46.6 cm² by approximately 40% as compared to an identical plan without collimation. The use of the DCS increased treatment time by 1-3 s per energy layer. Conclusions: The spread of the lateral penumbra of low-energy SS proton treatments may be greatly reduced with the use of this system at the cost of only a small penalty in delivery time. [ABSTRACT FROM AUTHOR]

In this review, we discuss three questions about the importance of studying purpose as a construct relevant to adolescence. We consider how finding a purpose can help youth answer questions such as 'Who am I?' and 'Where am I going?' and summarize the benefits of finding a purpose during adolescence. Purposeful youth are more agentic and driven in their lives, as well as happier and less susceptible to risks common in adolescence. We conclude by identifying areas that merit study, including the need to understand which contexts best scaffold the development of purpose among youth and the need for experimental research to strengthen causal claims. [ABSTRACT FROM AUTHOR]

Purpose: This paper presents a concept for a proton therapy system capable of delivering intensity modulated proton therapy using a fan beam of protons. This system would allow present and future gantry-based facilities to deliver state-of-the-art proton therapy with the greater normal tissue sparing made possible by intensity modulation techniques. Methods: A method for producing a divergent fan beam of protons using a pair of electromagnetic quadrupoles is described and particle transport through the quadrupole doublet is simulated using a commercially available software package. To manipulate the fan beam of protons, a modulation device is developed. This modulator inserts or retracts acrylic leaves of varying thickness from subsections of the fan beam. Each subsection, or beam channel, creates what effectively becomes a beam spot within the fan area. Each channel is able to provide 0-255 mm of range shift for its associated beam spot, or stop the beam and act as an intensity modulator. Results of particle transport simulations through the quadrupole system are incorporated into the MCNPX Monte Carlo transport code along with a model of the range and intensity modulation device. Several design parameters were investigated and optimized, culminating in the ability to create topotherapy treatment plans using distal-edge tracking on both phantom and patient datasets. Results: Beam transport calculations show that a pair of electromagnetic quadrupoles can be used to create a divergent fan beam of 200 MeV protons over a distance of 2.1 m. The quadrupole lengths were 30 and 48 cm, respectively, with transverse field gradients less than 20 T/m, which is within the range of water-cooled magnets for the quadrupole radii used. MCNPX simulations of topotherapy treatment plans suggest that, when using the distal edge tracking delivery method, many delivery angles are more important than insisting on narrow beam channel widths in order to obtain conformal target coverage. Overall, the sharp distal falloff of a proton depth-dose distribution was found to provide sufficient control over the dose distribution to meet objectives, even with coarse lateral resolution and channel widths as large as 2 cm. Treatment plans on both phantom and patient data show that dose conformity suffers when treatments are delivered from less than approximately ten angles. Treatment time for a sample prostate delivery is estimated to be on the order of 10 min, and neutron production is estimated to be comparable to that found for existing collimated systems. Conclusions: Fan beam proton therapy is a method of delivering intensity modulated proton therapy which may be employed as an alternative to magnetic scanning systems. A fan beam of protons can be created by a set of quadrupole magnets and modified by a dual-purpose range and intensity modulator. This can be used to deliver inversely planned treatments, with spot intensities optimized to meet user defined dose objectives. Additionally, the ability of a fan beam delivery system to effectively treat multiple beam spots simultaneously may provide advantages as compared to spot scanning deliveries. [ABSTRACT FROM AUTHOR]

Abstract: The current study focused on three aspects of identity development relevant to the adolescent years: being an authentic person, perceiving control over and consistency in one''s environment, and having consistent expectations from close others. In a two-wave study of adolescents (n = 750), we examined how these aspects change over the course of a year, as well as whether these aspects correspond to the Big Five personality traits. Results indicated three important findings. First, all three aspects evidenced the capacity for change over a year, and appeared more malleable than personality traits. Second, youth higher on all aspects reported a more adaptive personality profile. Third, changes on these aspects coincide with those on personality traits over the year. Findings are discussed with respect to future directions for studying the interplay of identity and personality development. [Copyright &y& Elsevier]

This chapter examines some possible biases evident in college students' self-reported gains, particularly social desirability and general tendencies to report gains, which appear to strongly influence the gains reported by first-year students. [ABSTRACT FROM AUTHOR]

Colleges and universities are placing a renewed emphasis on the importance of service and community engagement. Although the short-term effects of these college experiences are fairly well understood, little is known about the longterm impact of college volunteering and participating in engaged forms of learning (e.g. service-learning). This longitudinal study examines 416 participants during their freshman year of college, their senior year, and 13 years after graduation. Results show that both college volunteering and service-learning have positive, indirect effects on several forms of well-being during adulthood, including personal growth, purpose in life, environmental mastery, and life satisfaction. Specifically, these college experiences are associated with subsequent behaviors (adult volunteering) and attitudes and values (prosocial orientation), which in turn are positively associated with well being. Implications for research and practice are discussed. [ABSTRACT FROM AUTHOR]

The field of positive psychology has sparked significant interest for researchers, in part given the apparent potential for individuals higher on "positive" dispositions to experience better health and well‐being. However, as the field has grown, so too have the number of conceptually similar dispositions identified by researchers as important to study. As such, there is an increasing need for researchers to understand whether and how conceptually similar "positive" dispositions are actually unique, an issue that may not be unique to positive psychology but has worsened with the field's prominence. The current manuscript provides a roadmap for one approach to differentiating conceptually close constructs in psychology, with examples couched within positive psychology. We will discuss the importance of combining quantitative and qualitative inquiries, as well as the adoption of techniques from multiple psychology disciplines, in order to better distinguish characteristics frequently studied in positive psychology. [ABSTRACT FROM AUTHOR]