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Purpose: To examine the influence of monitor farm programmes on practice change using the Irish BETTER farm sheep programme as a case study. Methodology: A mixed methods approach combining 16 semi-structured and 69 structured interviews with benchmarking data analysis. Findings: Provision of intensive, tailored advice helped support practice change on the participating monitor farms. They increased productivity through changes in management practices, which positively impacted on financial performance. Monitor farmers also positively influenced members of their associated discussion groups to make practice changes. Practical Implications: Practical recommendations for similar programmes are discussed such as the need for different and additional extension approaches to influence and support the adoption of more complex practices and the potential for greater input from farmers into the design and implementation of extension programmes. Theoretical Implications: From a practice change perspective evaluating the influence of a more structured participatory extension programme (PEP) on a participating farmer is easier than the evaluation of the influence of the PEP on the wider farming community, particularly when the evaluation is not incorporated into the original programme design. Originality: Adding to the relatively small number of PEP evaluations in developed countries, the influence of monitor farm programmes on both the monitor farmer and their associated discussion group peers is examined for a wide range of practices using a mixed methods approach.

X-ray free electron laser (XFEL) sources coupled to high-power laser systems offer an avenue to study the structural dynamics of materials at extreme pressures and temperatures. The recent commissioning of the DiPOLE 100-X laser on the high energy density (HED) instrument at the European XFEL represents the state-of-the-art in combining x-ray diffraction with laser compression, allowing for compressed materials to be probed in unprecedented detail. Here, we report quantitative structural measurements of molten Sn compressed to 85(5) GPa and ∼ 3500 K. The capabilities of the HED instrument enable liquid density measurements with an uncertainty of ∼ 1 % at conditions which are extremely challenging to reach via static compression methods. We discuss best practices for conducting liquid diffraction dynamic compression experiments and the necessary intensity corrections which allow for accurate quantitative analysis. We also provide a polyimide ablation pressure vs input laser energy for the DiPOLE 100-X drive laser which will serve future users of the HED instrument. [ABSTRACT FROM AUTHOR]

BACKGROUND: Multiple sclerosis (MS) and allergies are both considered to be related to imbalanced Th1 and Th2 immune responses. Previous studies evaluating the relationship between MS and allergies provide conflicting results. OBJECTIVE: To assess allergies and asthma as risk factors for MS and as predictors of MS relapses in a pediatric cohort. METHODS: The environment and genetic risk factors for pediatric MS study is a national case-control project with 16 participating US sites. An environmental questionnaire is used that includes history of allergies in the first five years of life. Case-control data are entered in the pediatric MS Network database and cases at 12 of the 16 sites enter relapse data prospectively. Annualized relapse rate was calculated for patients with follow-up and adjusted for age at disease onset, gender, race, ethnicity, and use of disease-modifying therapy (DMT). RESULTS: We included 271 cases (mean age at disease onset of 15.7years and 62% female) and 418 controls. Relapse data were available for 193 cases. There was no difference in prevalence of allergies or asthma between cases and controls. Patients with food allergies had fewer relapses compared to patients without food allergies (0.14 vs 0.48, p=0.01). CONCLUSIONS: While allergies and asthma are not associated with pediatric MS, cases with food allergies have fewer relapses compared to those without food allergies.

Author(s): A. Lazicki [sup.1] , D. McGonegle [sup.2] , J. R. Rygg [sup.3] [sup.4] [sup.5] , D. G. Braun [sup.1] , D. C. Swift [sup.1] , M. G. Gorman [sup.1] [...], Carbon is the fourth-most prevalent element in the Universe and essential for all known life. In the elemental form it is found in multiple allotropes, including graphite, diamond and fullerenes, and it has long been predicted that even more structures can exist at pressures greater than those at Earth's core.sup.1-3. Several phases have been predicted to exist in the multi-terapascal regime, which is important for accurate modelling of the interiors of carbon-rich exoplanets.sup.4,5. By compressing solid carbon to 2 terapascals (20 million atmospheres; more than five times the pressure at Earth's core) using ramp-shaped laser pulses and simultaneously measuring nanosecond-duration time-resolved X-ray diffraction, we found that solid carbon retains the diamond structure far beyond its regime of predicted stability. The results confirm predictions that the strength of the tetrahedral molecular orbital bonds in diamond persists under enormous pressure, resulting in large energy barriers that hinder conversion to more-stable high-pressure allotropes.sup.1,2, just as graphite formation from metastable diamond is kinetically hindered at atmospheric pressure. This work nearly doubles the highest pressure at which X-ray diffraction has been recorded on any material. X-ray diffraction measurements of solid carbon compressed to pressures of about two terapascals (approximately twenty million atmospheres) find that carbon retains a diamond structure even under these extreme conditions.

Set against the backdrop of an absence of agricultural extension in the curriculum of agriculture degree programs in Ireland between 1990 and 2010, this paper examines the knowledge exchange skills needed by the next generation of farm advisors and presents the case of a practicebased postgraduate program in Ireland that seeks to address the competency gap created. It reviews an Irish post graduate program that has been designed to equip graduates with the competencies to work effectively in advisory roles. It combines student, graduate, and manager survey results on their experience and assessment of professional development with this program. The evolving role of front-line farm advisors to facilitators of knowledge exchange and innovation is recognised while a range of essential competencies are highlighted. The value of this postgraduate education for early career farm advisors is evidenced through building competencies in a range of areas and gaining a deeper understanding through applied research of the complexities of innovation adoption and the barriers to change for farmers and their families. The paper concludes that greater attention is needed to developing core competencies of farm advisors to build strong relationships of trust and influence with farmer clients. [ABSTRACT FROM AUTHOR]

We present measurements of diamond formation in doubly shocked Stycast 1266 epoxy (comprising C, H, Cl, N, and O) using in situ x-ray diffraction. Epoxy samples were reshocked against a LiF window to pressures between 80 and 148 GPa in experiments at the Omega Laser Facility. The pressure and temperature conditions were diagnosed in situ using velocimetry and optical pyrometry, respectively. X-ray diffraction patterns of the compressed epoxy are consistent with cubic diamond (Fd 3 ¯ m), indicating that diamond can precipitate not only from twice-shocked CH polystyrene [Kraus et al. Nat. Astron. 1, 606 (2017)] at these conditions but also from twice-shocked CH polymers with the addition of oxygen, nitrogen, and chlorine. These results, in combination with previous works on CH, CH 2 , CH 4 , and methane hydrate, support that diamond often, but not always, forms from CH-based compounds at extreme pressures and temperatures, indicating that the chemical composition, thermodynamic compression path, and kinetics play an important role. [ABSTRACT FROM AUTHOR]

We present the development of an experimental platform that can collect four frames of x-ray diffraction data along a single line of sight during laser-driven, dynamic-compression experiments at the National Ignition Facility. The platform is comprised of a diagnostic imager built around ultrafast sensors with a 2-ns integration time, a custom target assembly that serves also to shield the imager, and a 10-ns duration, quasi-monochromatic x-ray source produced by laser-generated plasma. We demonstrate the performance with diffraction data for Pb ramp compressed to 150 GPa and illuminated by a Ge x-ray source that produces ∼7 × 1011, 10.25-keV photons/ns at the 400 μm diameter sample. [ABSTRACT FROM AUTHOR]

This study investigates methods to optimize quasi-monochromatic, ∼10 ns long x-ray sources (XRS) for time-resolved x-ray diffraction measurements of phase transitions during dynamic laser compression measurements at the National Ignition Facility (NIF). To support this, we produce continuous and pulsed XRS by irradiating a Ge foil with NIF lasers to achieve an intensity of 2 × 1015 W/cm2, optimizing the laser-to-x-ray conversion efficiency. Our x-ray source is dominated by Ge He-α line emission. We discuss methods to optimize the source to maintain a uniform XRS for ∼10 ns, mitigating cold plasma and higher energy x-ray emission lines. [ABSTRACT FROM AUTHOR]

X-ray diffraction is a powerful measurement technique for determining material properties, and it is now possible to perform these experiments at pressures exceeding 1 TPa [Rygg et al., Rev. Sci. Instrum. 91, 043902 (2020)] at the National Ignition Facility (NIF). The x-ray source for these experiments is the quasi-monochromatic Heα emission from metal foils heated to multi-keV temperatures. A critical aspect for understanding the sample's thermodynamic state is the amount of heating caused by absorption of the probe x-rays. In this work, we characterize the performance of the Ge foil x-ray source over more than 60 NIF x-ray diffraction experiments. We use this information to constrain the level of diffraction sample heating from the x-ray source and discuss the impact on the thermodynamic state. [ABSTRACT FROM AUTHOR]

In cases of sexual assaults involving children, biological evidence such as semen is often found on clothes rather than on intimate swabs. Two cases involving young girls were submitted to one of the AFSP BFF forensic science laboratories instigating further research into the background levels of semen on children's underwear after being laundered, without sexual acts occurring. This study considered the potential for background levels of semen in the washing machine and the levels of semen transferred with varying laundry storage and washing arrangements. The results concur with previous studies that low levels of spermatozoa can transfer during washing; however, this study demonstrated that background levels of semen can be present on children's clothing during domestic laundering activities which include male underwear when there are sexually active males within the household. Further, that semen can persist in the washing machine even after three washes. This study has produced data which will assist forensic scientists to evaluate cases of child abuse in a domestic setting. • Evaluating the significance of spermatozoa on children's underwear when a background of spermatozoa may be expected. • Sensitivities and limitations of specific methods of examination and detection. • Importance of ongoing data collection to reliably evaluate transfer mechanisms. [ABSTRACT FROM AUTHOR]