3,648 research outputs found

    Synthetic Hagfish Slime Mimetics: Mechanical Characterization

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    Hagfish are ancient animals that eject a slime when attacked by predators. The slime that the hagfish emit is almost entirely composed of water but protein strands within the slime cause the slime to have incredible strength. However, these protein strands will be formed synthetically for the purposes of our experiment. To defend against foes, the Navy launches plastic ropes into the propellers of enemy warships in order to decrease the thrust of the motors. In a push to find a more biodegradable solution, the utilization of hagfish slime has shown great promise in stopping propellers.While we know that the slime can stop propellers from functioning properly we hope to understand how. What specific mechanical properties allow for this phenomena? Initial data indicates slime in saltwater is stronger and has greater stretching capability, likely due to ionic crosslinking. We hope to maximize the strength of this incredible biomaterial.https://digitalcommons.usu.edu/fsrs2021/1065/thumbnail.jp

    Synthetic Hagfish Slime: Mechanical Characterization

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    Hagfish are ancient animals that eject a strong slime when attacked by predators. The slime that the hagfish emit is composed of protein strands that cause it to have incredible strength. To defend against foes, the Navy launches plastic ropes into the propellers of enemy warships in order to decrease the thrust of the motors. In a push to find a more biodegradable solution, the utilization of hagfish slime has shown greatpromise in stopping propellers.We hope to understand how this remarkable biomaterial withstands the impact of a sharp and quickly rotating propeller, while simultaneously reducing the thrust of the propeller. What specific mechanical properties allow for this phenomena? From this research we can maximize the capabilities of this incredible biomaterial by testing it in various conditions.The core application of this project is the eventual implementation of the synthetic hagfish slime into the Navy’s arsenal. Beyond this, however, the protein threads may also be useful in medical applications

    The effectiveness, safety and cost-effectiveness of cytisine versus varenicline for smoking cessation in an Australian population: a study protocol for a randomized controlled non-inferiority trial

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    Smoking cessation medications are effective but often underutilised because of costs and side effects. Cytisine is a plant-based smoking cessation medication with over 50 years of use in Central and Eastern Europe. While cytisine has been found to be well-tolerated and more effective than nicotine replacement therapy, direct comparison with varenicline have not been conducted. This study evaluates the effectiveness, safety and cost-effectiveness of cytisine compared with varenicline.Two arm, parallel group, randomised, non-inferiority trial, with allocation concealment and blinded outcome assessment.Australian population-based study.Adult daily smokers (N=1266) interested in quitting will be recruited through advertisements and Quitline telephone-based cessation support services.Eligible participants will be randomised (1:1 ratio) to receive either cytisine capsules (25-day supply) or varenicline tablets (12-week supply), prescribed in accordance with the manufacturer's recommended dosing regimen. The medication will be mailed to each participant's nominated residential address. All participants will also be offered standard Quitline behavioural support (up to six 10-12 minute sessions).Assessments will be undertaken by telephone at baseline, 4- and 7-months post-randomisation. Participants will also be contacted twice (two and four weeks post-randomisation) to ascertain adverse events, treatment adherence and smoking status. The primary outcome will be self-reported 6-month continuous abstinence from smoking, verified by carbon monoxide at 7-month follow-up. We will also evaluate the relative safety and cost-effectiveness of cytisine compared with varenicline. Secondary outcomes will include self-reported continuous and 7-day point prevalence abstinence and cigarette consumption at each follow-up interview.If cytisine is as effective as varenicline, its lower cost and natural plant-based composition may make it an acceptable and affordable smoking cessation medication that could save millions of lives worldwide

    Surface superconductivity and order parameter suppression in UPt3_3

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    We show that a recent measurement of surface superconductivity in UPt3_3 (Keller {\it et. al.}, Phys. Rev. Lett. {\bf 73}, 2364 (1994)) can be understood if the superconducting pair wavefunction is suppressed anisotropically at a vacuum to superconductor interface. Further measurements of surface superconductivity can distinguish between the various phenomenological models of superconducting UPt3_3.Comment: 4 pages, latex, 2 Figures available upon request ([email protected]

    Co-Administration of Injected and Oral Vaccine Candidates Elicits Improved Immune Responses over Either Route Alone

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    Infectious diseases continue to be a significant cause of morbidity and mortality, and although efficacious vaccines are available for many diseases, some parenteral vaccines elicit little or no mucosal antibodies which can be a significant problem since mucosal tissue is the point of entry for 90% of pathogens. In order to provide protection for both serum and mucosal areas, we have tested a combinatorial approach of both parenteral and oral administration of antigens for diseases caused by a viral pathogen, Hepatitis B, and a fungal pathogen, Coccidioides. We demonstrate that co-administration by the parenteral and oral routes is a useful tool to increase the overall immune response. This can include achieving an immune response in tissues that are not elicited when using only one route of administration, providing a higher level of response that can lead to fewer required doses or possibly providing a better response for individuals that are considered poor or non-responders

    The context, influences and challenges for undergraduate nurse clinical education: Continuing the dialogue

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    Introduction – Approaches to clinical education are highly diverse and becoming increasingly complex to sustain in complex milieu Objective – To identify the influences and challenges of providing nurse clinical education in the undergraduate setting and to illustrate emerging solutions. Method: A discursive exploration into the broad and varied body of evidence including peer reviewed and grey literature. Discussion - Internationally, enabling undergraduate clinical learning opportunities faces a range of challenges. These can be illustrated under two broad themes: (1) Legacies from the past and the inherent features of nurse education and (2) Challenges of the present, including, population changes, workforce changes, and the disconnection between the health and education sectors. Responses to these challenges are triggering the emergence of novel approaches, such as collaborative models. Conclusion(s) – Ongoing challenges in providing accessible, effective and quality clinical learning experiences are apparent

    Experience and expectations of transition to higher education : a qualitative exploration

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    Transition to higher education is challenging, and more so for some groups. The transition from Level 3 foundation year into Level 4 is an opportunity to explore student perspectives on transition. Qualitative survey and focus group data were collected from current and previous Level 3 students, to ascertain student perceptions about induction, level of belonging, confidence about Level 4 and to identify useful support sources. Over a third of eligible Level 3 students (n = 102) participated, but participation amongst eligible Level 4, 5 and 6 students was limited. Despite the heterogeneous nature of Level 3 students the majority recognised the value of the foundation year. Most Level 3 students did not identify with the university. Those who did highlighted the importance of social outlets such as clubs and societies. A major cause of dissatisfaction was perceived lack of clarity about the foundation year, including the programme, subjects and physical location of the course. This was apparent across all ethnicities, age groups and genders. Among previous Level 3 students, personal sources of support were uniformly valued although the precise source varied by year of study. Support from academic staff, via office hours and as personal tutors, was rated as most important. Enabling academic staff to offer support to students throughout their studies, and clear consistent information available throughout an ongoing transition, may help to minimise these issues

    The UV/optical spectra of the Type Ia supernova SN 2010jn: a bright supernova with outer layers rich in iron-group elements

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    Radiative transfer studies of Type Ia supernovae (SNe Ia) hold the promise of constraining both the time-dependent density profile of the SN ejecta and its stratification by element abundance which, in turn, may discriminate between different explosion mechanisms and progenitor classes. Here we present a detailed analysis of Hubble Space Telescope ultraviolet (UV) and ground-based optical spectra and light curves of the SN Ia SN 2010jn (PTF10ygu). SN 2010jn was discovered by the Palomar Transient Factory (PTF) 15 days before maximum light, allowing us to secure a time-series of four UV spectra at epochs from -11 to +5 days relative to B-band maximum. The photospheric UV spectra are excellent diagnostics of the iron-group abundances in the outer layers of the ejecta, particularly those at very early times. Using the method of 'Abundance Tomography' we have derived iron-group abundances in SN 2010jn with a precision better than in any previously studied SN Ia. Optimum fits to the data can be obtained if burned material is present even at high velocities, including significant mass fractions of iron-group elements. This is consistent with the slow decline rate (or high 'stretch') of the light curve of SN 2010jn, and consistent with the results of delayed-detonation models. Early-phase UV spectra and detailed time-dependent series of further SNe Ia offer a promising probe of the nature of the SN Ia mechanism.Comment: 17 pages, 9 figures (v3: several small updates to content including models; v2: metadata fixed), MNRAS, in pres
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