Advanced Strain-Isolation-Pad Material with Bonded Fibrous Construction

The feasibility of utilizing air lay and liquid lay felt deposition techniques to fabricate strain isolation pad (SIP) materials for the Space Shuttle Orbiter was demonstrated. These materials were developed as candidate replacements for the present needled felt SIP used between the ceramic tiles and the aluminum skin on the undersurface of the Orbiter. The SIP materials that were developed consisted of high temperature aramid fibers deposited by controlled fluid (air or liquid) carriers to form low density unbonded felts. The deposited felts were then bonded at the fiber intersections with a small amount of high temperature polyimide resin. This type of bonded felt construction can potentially eliminate two of the problems associated with the present SIP, viz., transmittal of localized stresses into the tiles and load history dependent mechanical response. However, further work is needed to achieve adequate through thickness tensile strength in the bonded felts

Experimental high-dimensional two-photon entanglement and violations of generalised Bell inequalities

Quantum entanglement plays a vital role in many quantum information and communication tasks. Entangled states of higher dimensional systems are of great interest due to the extended possibilities they provide. For example, they allow the realisation of new types of quantum information schemes that can offer higher information-density coding and greater resilience to errors than can be achieved with entangled two-dimensional systems. Closing the detection loophole in Bell test experiments is also more experimentally feasible when higher dimensional entangled systems are used. We have measured previously untested correlations between two photons to experimentally demonstrate high-dimensional entangled states. We obtain violations of Bell-type inequalities generalised to d-dimensional systems with up to d = 12. Furthermore, the violations are strong enough to indicate genuine 11-dimensional entanglement. Our experiments use photons entangled in orbital angular momentum (OAM), generated through spontaneous parametric down-conversion (SPDC), and manipulated using computer controlled holograms

Season of the year influences infection rates following total hip arthroplasty

To research the influence of season of the year on periprosthetic joint infections. METHODS We conducted a retrospective review of the entire Medicare files from 2005 to 2014. Seasons were classified as spring, summer, fall or winter. Regional variations were accounted for by dividing patients into four geographic regions as per the United States Census Bureau (Northeast, Midwest, West and South). Acute postoperative infection and deep periprosthetic infections within 90 d after surgery were tracked. RESULTS In all regions, winter had the highest incidence of periprosthetic infections (mean 0.98%, SD 0.1%) and was significantly higher than other seasons in the Midwest, South and West (P \u3c 0.05 for all) but not the Northeast (P = 0.358). Acute postoperative infection rates were more frequent in the summer and were significantly affected by season of the year in the West. CONCLUSION Season of the year is a risk factor for periprosthetic joint infection following total hip arthroplasty (THA). Understanding the influence of season on outcomes following THA is essential when risk-stratifying patients to optimize outcomes and reduce episode of care costs. © The Author(s) 2017

Eating Biodiversity: Investigating the Links Between Grassland Biodiversity and Quality Food Production

Modern food production systems are generally detrimental to biodiversity, and the widespread loss of species-diverse grassland as a consequence of intensive farming methods is well documented. Since the 1980s, a range of policy measures and financial incentives for farmers have been introduced in Europe to halt (and in some cases, reverse) this trend, primarily to meet environmental objectives of species and habitat conservation and landscape protection. Biodiversity, where associated with agricultural production, has largely been regarded as a positive \u27externality\u27 to the process of food production; a ‘product’ which benefits wider society without necessarily conferring an agricultural benefit to the producer. However, with increasing emphasis on food quality, and the marketing of food products by geographical origin, method of production, gastronomic value and nutritional and health properties, there is potential to improve financial returns for farmers and the wider rural economy. Production in which grassland biodiversity is an ‘input’ to the livestock production food chain are embedded in some speciality systems, notably in mountain areas of Europe (Peeters and Frame, 2002). In the context of conserving grassland biodiversity there is a need to improve our understanding of the links between food products and animal diets, including pasture composition. This paper outlines a 3-year project funded by the UK RELU programme (RELU, 2005) which commenced in 2005. Results are not yet available so this summary focuses on the strategy being followed and the wider implications of linking enhanced food-product value to biodiversity

The chemistry and mode of action of naturally-occurring growth regulators from avena

This thesis is concerned with the nature and function of endogenous chemicals in the maintenance of oat seed dormancy. The prime germination inhibitors within dormant Avena spp. Are characterised and their development pattern during seed maturation and after-ripening established. Their in vitro biological activities as inhibitors of germination and reserve starch degradation are also shown. Abscisic acid (ABA) and a group of saturated, medium-chain length carboxylic acids (MCFA) have been detected in dormant Avena seed. Levels of endogenous fatty acid and ABA were monitored in developing grain of dormant and non-dormant oat species. It is shown that the highest amounts of MCFA are present within dormant seed, these levels decreasing during, or prior to, that period of increasing seed germinability. Reduced amounts of MCFA are associated with non-dormant grain. It is shown that oat seed germination correlates well with V the endogenous level of MCFA, particularly nonanoic acid. It is speculated that volatile fatty acids are lost from dormant wild oat grain during dry storage by a natural physical process involving gradual volatilisation. ABA did not appear to be directly involved with oat seed dormancy. Large variations in ABA content only occurred in hydrated grain of both species, the level increasing markedly during grain filling. As desiccation on the parent plant proceeded the ABA content of seeds rapidly decreased. At harvest the levels of free ABA in common and wild oat were found to be similar, although their germinations were 65% and 0%, respectively. It is shown that ABA is not efficacious as an inhibitor of germination in the common oat. MCFA are detected in the 3 inhibitor mixtures isolated from a wide variety of plant material. It is proposed that they contribute to the inhibitory properties of this complex. Fatty acids in the series pentanoic to undecanoic are tested for their physiological activity in seed germination. MCFA are found to inhibit seed germination and suppress gibberellin-induced amylolysis in barley at concentrations below 10-3M. In general, nonanoic acid is the most effective treatment. At a concentration of about 2 x 10-3M nonanoic acid reduces the germination of non-dormant oat seed by 50%. MCFA-induced inhibition of lettuce seed germination is shown to be similar to natural thermodormancy, being reversed by treatment with red light or applications of cytokinin or gibberellin. It is speculated that MCFA impose their inhibitory action by modifying membrane function and/or enzyme activity within the plant cell

Land use change: implications for Australian Capital Territory Water use

Managing water resources to ensure environmental values are maintained, whilst allowing for continued economic development is a major challenge facing many areas including the Australian Capital Territory (ACT). This paper reports on a GIS based investigation of the implications of land use change on ACT water use. The paper describes a suite of tools that are collectively termed PLUCA (Platform for Land use Change Assessment). Areas with the potential for land use change were identified through land capability assessment and by investigation of the suitability of land for development of alternate industries. Spatial data including slope, aspect, a wetness index, climatic surfaces, geology and consideration of the minimum viable scale of industry were analysed in the study. A coarse land use class – water use relationship estimated for the ACT was used to determine the maximum potential water use resulting from land use change. Three scenarios, based on different levels of land use change were constructed to simulate high, medium and low levels of potential landuse change in the ACT. The estimated reduction in streamflow for the maximum development scenario, was around 6.8% of the average annual runoff from the ACT. This scenario represented modification of only 3.9% of the total land area. This study demonstrates the potential for the use of GIS in the optimisation of landuse from biophysical characteristics. The implications of such changes should they occur were calculated through investigation of the annual average reduction in streamflow. The study demonstrates the use of GIS techniques in quantifying interactions at appropriate scales for decision making. The development of improved decision support tools is also outlined. <br

Picosecond laser ranging at wavelengths up to 2.4 μm using an InAs avalanche photodiode

Time-of-flight measurements using pulsed laser illumination in the wavelength region between 1.3 to 2.37 μm have been demonstrated with an InAs avalanche photodiode (APD). InAs is photo-sensitive at wavelengths up to 3.5 μm and with predominantly electron multipli- cation reducing detector noise, InAs APDs have clear potential for sen- sitive optical measurements of picosecond transients in the mid-wave infrared. Laboratory-based demonstrations of time-of-flight ranging using InAs APDs operated at room temperature is described

Scaling-up beginning farmers for wholesale production

With nearly 15 million people that live within 250 miles of Kansas City, the demand for local food is increasing. Local beginning farmers in the region want to reach an emerging wholesale market. However, selling directly to consumers demands different skills than the wholesale market requires. There are many educational programs offered in the region that are focused on direct to consumer sales. Unfortunately, there is a gap in educational programs that are offered to support beginning farmers that wish to expand into wholesale markets. In 2018, the Beginning Farmer Wholesale Project was started within the Growing Growers Kansas City program in congruence with the overall mission to improve the skills and livelihoods of the region’s growers. The project offers support and training to beginning farmers as they begin to navigate new market opportunities. It provides on-farm technical assistance, mentorship, opportunities to connect to wholesale buyers, a workshop series, a manual and an extensive foodshed GIS map. The ongoing project has seen several contributions to improving farmer access to wholesale markets. As of 2020, six workshops have been conducted that have covered a variety of farm production and marketing skills. Six farmer mentees have enrolled in the mentor program which enlists nine farmer mentors from across the region. Over twenty farmers have utilized the technical assistance service on their Kansas and Missouri farm operations and the farmer buyer matching program has resulted in thirteen beginning farmers gaining access to new markets. The project highlights the value of collaboration among organizations and the importance of offering multiple farmer services in order to improve wholesale access

Tryptophan synthase uses an atypical mechanism to achieve substrate specificity

Tryptophan synthase (TrpS) catalyzes the final steps in the biosynthesis of L-tryptophan from L-serine (Ser) and indole-3-glycerol phosphate (IGP). We report that native TrpS can also catalyze a productive reaction with L-threonine (Thr), leading to (2S,3S)-β-methyltryptophan. Surprisingly, β-substitution occurs in vitro with a 3.4-fold higher catalytic efficiency for Ser over Thr using saturating indole, despite >82,000-fold preference for Ser in direct competition using IGP. Structural data identify a novel product binding site and kinetic experiments clarify the atypical mechanism of specificity: Thr binds efficiently but decreases the affinity for indole and disrupts the allosteric signaling that regulates the catalytic cycle