1,730 research outputs found

    Irradiation Enhances Strength and Deformability of Nano-Architected Metallic Glass

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    The quest for radiation-damage tolerant materials has found good candidates in nanoporous metals, whose abundance of free surfaces provides ample sinks for radiation-induced defects, as well as in metallic glasses, whose characteristic failure via shear banding can be alleviated by irradiation. This type of catastrophic failure in metallic glass can also be suppressed by reducing their dimensions to the nanoscale. To combine the beneficial effects of resilience against irradiation in materials containing many free surfaces and nano-sized metallic glasses, the authors fabricate Zr–Ni–Al metallic glass nano-architecture and irradiate them with 12 MeV Ni^(4+) ions. These 3D nanolattices are composed of hollow beams of sputtered metallic glass with beam wall thicknesses ≈10–100 nm, with a relative density of ≈5%, which renders them to be 20 times lighter than their bulk-level counterparts. The authors find that the thickest-walled nanolattices, those with a median wall thickness of ≈88 nm, are able to withstand irradiation without significant contraction; all other substantially shrunk; and collapsed upon irradiation. In situ nanomechanical experiments on the irradiated samples compressed inside a scanning electron microscope (SEM) reveal substantial improvement in mechanical response upon irradiation, with an average increase in yield strength of 35.7% and a significant enhancement in deformability. Enhanced deformability upon irradiation is apparent from the nanolattices' accommodation of larger strains before any kind of failure, as well as the presence of smaller strain bursts and stress drops throughout the stress–strain response. The irradiated nanolattices are largely intact after compression, with in situ SEM videos demonstrating a layer-by-layer like collapse in the irradiated nanolattices in contrast to the catastrophic failure with complete destruction of the failed layers observed in equivalent as-fabricated samples. This work points to nano-architected metallic glasses being a promising candidate for creating ultra-lightweight, radiation tolerant materials, and irradiation as a promising technique for improving the mechanical response of metallic glass nanolattices with stiffness on the order of 250 MPa

    Sustainability Survey report

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    Although the idea of sustainability means different things to different people, one of the most common definitions comes from the UN’s 1987 Brundtland Report, which states that sustainability is that which meets the needs of the present without compromising the ability of future generations to meet their own needs. In practice, sustainability means balancing environmental protection with economic vitality and social justice. Since the 1990s, sustainability has become a powerful framework for organizational transformation, particularly at institutions of higher education. Today over 1,350 colleges and universities offer degrees in sustainability and use sustainability as a guiding principle for administrative decisions across campus. On our own campus, the Environmental Studies and Sustainability major grew 144% in the past year while enrollment in other programs declined. For many people born in the early twenty-first century, sustainability is an exciting movement that seeks solutions to the daunting economic, environmental, and social problems that their generation will face. As training grounds for the future, universities like Northern have a responsibility to prepare today’s students for these global challenges

    College physical activity is related to mid-life activity levels in women

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    It has been suggested, but not clearly established, that physical activity (PA) during the college years is a determinant of long-term PA patterns. The purpose of this study was to examine the relationship between PA during the college years and current PA in college-educated women. Fifty-five college-educated women, aged 39.3 ± 6.5 y, were recruited for this study and were, on average, 14.9 ± 7.4 y post-college. Participant\u27s history of PA during college years and the present time was determined from the Lifetime Physical Activity Questionnaire. A brief demographic questionnaire that addressed current PA patterns was also administered. Results showed a significant correlation between leisure activity (LA) during college years and current LA (r = 0.424, p = 0.001). There was no difference between median college LA and current LA (22.4 and 27.9 MET hours per week, respectively, p = 0.129). However, total college PA reported was significantly lower than total current PA (34.7 and 70.7 MET hours per week, respectively, p = 0.001), with this difference due to an increase in household activities during mid-life. Marital status, the presence of children under the age of 18 in the home, and employment status had no significant impact on LA for this sample. These data suggest that leisure-time PA patterns practiced during college years may carry over to mid- life

    Pleasant emotions widen thought-action repertoires, develop long-term resources, and improve reaction time performance: A multi-study examination of the Broaden-and-Build theory among athletes

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    The authors investigated relationships between emotions, coping, and resilience across two studies. In Study 1a, 319 athletes completed dispositional questionnaires relating to the aforementioned constructs. In Study 1b, 126 athletes from Study 1a repeated the same questionnaires 6months later. In Study 2, 21 athletes were randomly allocated to an emotional (e.g., pleasant or unpleasant emotions) or control group and undertook a laboratory-based reaction-time task across three time points. Questionnaires and salivary cortisol samples were collected before and after each performance with imagery-based emotional manipulations engendered during the second testing session. Partial longitudinal evidence of the broaden-and-build effects of pleasant emotions was found. Pleasant emotions may undo lingering cognitive resource losses incurred from previous unpleasant emotional experiences. In Study 2, pleasant and unpleasant emotions had an immediate and sustained psychophysiological and performance impact. Taken together, this research supports the application of broaden-and-build theory in framing emotional interventions for athletes

    Stress appraisals influence athletic performance and psychophysiological response during 16.1 km cycling time trials

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    Objectives: We examined how stress appraisals were associated with emotions, coping behaviours, as well as subjective and objective measures of performance.Design: Prospective field- and laboratory-based studies.Methods: In Study 1, 192 athletes completed process-oriented psychometrics pertaining to the aforementioned constructs throughout a sporting competition. Study 2 utilised an experimental design to assess the causal influence of stress appraisals on performance, cortisol, and psychological variables. Thirty gender-matched athletes were randomly assigned to either a stress appraisal (e.g., challenge, threat, benefit, or harm/loss) or the control group. Participants completed three 16.1km cycling time trials (TT) on a cycle ergometer, with their appropriate stress appraisal engendered via falsified performance feedback throughout the final TT. Salivary cortisol samples and psychometrics (e.g., appraisals, emotions, and coping) were collected before and after each TT.Results: The results of Study 1 revealed a sequential link between challenge stress appraisals and perceived goal attainment via pleasant emotions and task-oriented coping behaviours. Threat stress appraisals inversely related to goal attainment via unpleasant emotions and both distraction- and disengagement-oriented coping. In Study 2, no significant psychophysiological or performance differences were found across genders. The temporal orientation of stress appraisals influenced objective cycling TT performance. Benefit and harm/loss stress appraisals significantly facilitated or inhibited performance, respectively. Cortisol spikes were observed in the stress appraisal group’s threat, challenge, and benefit, with a decline detected within the harm/loss group. Whilst the process of winning is physiologically stressful, the fear of defeat may be more stressful than losing itself. Conclusion: Stress appraisals influence subjective and objective performance, as well as neuroendocrine and psychological responses to stress. Stress Appraisals Influence Athletic Performance and Psych

    Development of a Self‐Management Theory‐Guided Discharge Intervention for Parents of Hospitalized Children

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    Background Parents of hospitalized children, especially parents of children with complex and chronic health conditions, report not being adequately prepared for self‐management of their child\u27s care at home after discharge. Problem No theory‐based discharge intervention exists to guide pediatric nurses\u27 preparation of parents for discharge. Purpose To develop a theory‐based conversation guide to optimize nurses\u27 preparation of parents for discharge and self‐management of their child at home following hospitalization. Methods Two frameworks and one method influenced the development of the intervention: the Individual and Family Self‐Management Theory, Tanner\u27s Model of Clinical Judgment, and the Teach‐Back method. A team of nurse scientists, nursing leaders, nurse administrators, and clinical nurses developed and field tested the electronic version of a nine‐domain conversation guide for use in acute care pediatric hospitals. Conclusions The theory‐based intervention operationalized self‐management concepts, added components of nursing clinical judgment, and integrated the Teach‐Back method. Clinical Relevance Development of a theory‐based intervention, the translation of theoretical knowledge to clinical innovation, is an important step toward testing the effectiveness of the theory in guiding clinical practice. Clinical nurses will establish the practice relevance through future use and refinement of the intervention

    Irradiation Enhances Strength and Deformability of Nano-Architected Metallic Glass

    Get PDF
    The quest for radiation-damage tolerant materials has found good candidates in nanoporous metals, whose abundance of free surfaces provides ample sinks for radiation-induced defects, as well as in metallic glasses, whose characteristic failure via shear banding can be alleviated by irradiation. This type of catastrophic failure in metallic glass can also be suppressed by reducing their dimensions to the nanoscale. To combine the beneficial effects of resilience against irradiation in materials containing many free surfaces and nano-sized metallic glasses, the authors fabricate Zr–Ni–Al metallic glass nano-architecture and irradiate them with 12 MeV Ni^(4+) ions. These 3D nanolattices are composed of hollow beams of sputtered metallic glass with beam wall thicknesses ≈10–100 nm, with a relative density of ≈5%, which renders them to be 20 times lighter than their bulk-level counterparts. The authors find that the thickest-walled nanolattices, those with a median wall thickness of ≈88 nm, are able to withstand irradiation without significant contraction; all other substantially shrunk; and collapsed upon irradiation. In situ nanomechanical experiments on the irradiated samples compressed inside a scanning electron microscope (SEM) reveal substantial improvement in mechanical response upon irradiation, with an average increase in yield strength of 35.7% and a significant enhancement in deformability. Enhanced deformability upon irradiation is apparent from the nanolattices' accommodation of larger strains before any kind of failure, as well as the presence of smaller strain bursts and stress drops throughout the stress–strain response. The irradiated nanolattices are largely intact after compression, with in situ SEM videos demonstrating a layer-by-layer like collapse in the irradiated nanolattices in contrast to the catastrophic failure with complete destruction of the failed layers observed in equivalent as-fabricated samples. This work points to nano-architected metallic glasses being a promising candidate for creating ultra-lightweight, radiation tolerant materials, and irradiation as a promising technique for improving the mechanical response of metallic glass nanolattices with stiffness on the order of 250 MPa

    The Role of Personality Traits in Young Adult Fruit and Vegetable Consumption

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    This project investigated how individual differences in the big-five personality traits (neuroticism, extraversion, openness to experience, conscientiousness, and agreeableness) predicted plant-food consumption in young adults. A total of 1073 participants from two samples of young adults aged 17–25 reported their daily servings of fruits, vegetables, and two unhealthy foods for comparison purposes using an Internet daily diary for 21 or 13 days (micro-longitudinal, correlational design). Participants also completed the Neuroticism, Extraversion, Openness Five Factor Inventory (NEO-FFI) measure of personality, and demographic covariates including gender, age, ethnicity, and body mass index (BMI). Analyses used hierarchical regression to predict average daily fruit and vegetable consumption as separate dependent variables from the demographic covariates (step 1) and the five personality traits (step 2). Results showed that young adults higher in openness and extraversion, and to some extent conscientiousness, ate more fruits and vegetables than their less open, less extraverted, and less conscientious peers. Neuroticism and agreeableness were unrelated to fruit and vegetable consumption. These associations were unique to eating fruit and vegetables and mostly did not extend to unhealthy foods tested. Young adult women also ate more fruit and vegetables than young adult men. Results suggest that traits associated with greater intellect, curiosity, and social engagement (openness and extraversion), and to a lesser extent, discipline (conscientiousness) are associated with greater plant-food consumption in this population. Findings reinforce the importance of personality in establishing healthy dietary habits in young adulthood that could translate into better health outcomes later in life
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