Low-temperature synthesis of zintl compounds with a single-source molecular precursor

Thermolysis of the heterobimetallic phosphinidene complex [Sb(PCy)3]2- Li6.6HNMe2 (Cy = C6H11) at 303 to 313 kelvin gives Zintl compounds containing (Sb7)3- anions. The complex thus constitutes a stable molecular single-source precursor to Zintl compounds and provides a potential low-temperature route to photoactive alkali metal antimonates. The new chemical reaction involved, which is driven thermodynamically by the formation of P-P bonds, has implications in the low-temperature synthesis of other technologically important materials (such as gallium arsenide).     

Dynamical Signature of the Mott-Hubbard Transition in Ni(S,Se)2

The transition metal chalcogenide Ni(S,Se)2 is one of the few highly correlated, Mott-Hubbard systems without a strong first-order structural distortion that normally cuts off the critical behavior at the metal-insulator transition. The zero-temperature (T) transition was tuned with pressure, and significant deviations were found near the quantum critical point from the usual T1/2 behavior of the conductivity characteristic of electron-electron interactions in the presence of disorder. The transport data for pressure and temperature below 1 kelvin could be collapsed onto a universal scaling curve.     

Strong, transparent, multifunctional, carbon nanotube sheets

Individual carbon nanotubes are like minute bits of string, and many trillions of these invisible strings must be assembled to make useful macroscopic articles. We demonstrated such assembly at rates above 7 meters per minute by cooperatively rotating carbon nanotubes in vertically oriented nanotube arrays (forests) and made 5-centimeter-wide, meter-long transparent sheets. These self-supporting nanotube sheets are initially formed as a highly anisotropic electronically conducting aerogel that can be densified into strong sheets that are as thin as 50 nanometers. The measured gravimetric strength of orthogonally oriented sheet arrays exceeds that of sheets of high-strength steel. These nanotube sheets have been used in laboratory demonstrations for the microwave bonding of plastics and for making transparent, highly elastomeric electrodes; planar sources of polarized broad-band radiation; conducting appliqués; and flexible organic light-emitting diodes.     

Studies on Sarcocystis species III: The macrocystic species of sheep

Three forms of macrocyst were studied in sheep. On the basis of their dimensions and cyst-wall ultrastructure, thin cysts were found to be a separate species from fat and oesophageal cysts, but were also transmitted by cats. Sporocysts derived from fat and thin cysts had similar dimensions. It is proposed that the thin species be named S. medusiformis n.sp.     

An exploratory study to investigate animal health and reproductive wastage among Australian meat goat producers

The Australian goat meat industry has grown significantly in the last decade, with the value of exports nearly tripling. However, because carcase weight has remained constant over this time, the drivers of industry growth are price and supply. Animal health and reproduction are key factors contributing to supply and productivity, yet limitations to production management are poorly understood, hampering advice for effective intervention. This exploratory study aims to provide insights into the animal health and reproductive management practices and perceptions among meat goat producers in Australia. To achieve this aim, 20 producers, located in New South Wales, Queensland, Western Australia and Victoria, operating under different production systems were interviewed. The results of this study suggest that animal health management could be improved and that producers perceive a lack of relevant and species-specific information available to help them make informed decisions. Reproductive management and records varied greatly across producers interviewed. Kid loss was identified as an issue, with a 28% estimated average (6%–47% range) of losses from kidding until weaning. Producers identified predation, doe nutrition and mismothering as the biggest contributors to kid loss, with the majority of losses occurring within a week of birth. All producers believed management could minimise kid loss. This study highlights the importance of improving reproductive rates among goat enterprises and provides new information on the current practices within the Australian meat goat industry. This may assist the development of appropriate strategies for improving health and reproductive management and delivery of advice to producers.     

Effects of high fat,modified wet,corn distiller's grains plus solubles on beef steer performance and carcass characteristics

Corn distiller's grains plus solubles (DGS) have become a common replacement for shelled corn in diets of finishing steers. Numerous studies have evaluated DGS inclusion, both wet (WDGS) and dry (DDGS), into feedlot diets with conflicting reports on feedlot performance and subsequent meat quality. Many authors have failed to describe the nutrient composition of the DGS utilized in their studies making it difficult to determine why different studies have different results. The objective of this study was to evaluate the feedlot performance and subsequent meat quality characteristics of steers fed high fat (10.36±0.72%), modified wet corn distiller's grains plus solubles (HWDGS) at 0, 25, 40, and 70% of the diet dry matter (DM). Angus cross steers (n=240; 335±55 kg) were blocked by source and stratified within block (3 blocks) by body weight (BW) to 32 treatment pens containing either 6 or 10 steers/pen. Pens within block were randomly assigned to one of four diets containing 15% corn silage: (1) 76.9% shelled corn, 6.4% soybean meal 1.5% limestone, 0.2% premix (0 HWDGS); (2) 25.0% HWDGS, 58.20% shelled corn 1.6% limestone, 0.2% premix (25 HWDGS); (3) 40.0% HWDGS, 42.74% shelled corn 2.06% limestone, 0.2% premix (40 HWDGS); (4) 70.0% HWDGS, 12.30% shelled corn 2.5% limestone, 0.2% premix (70 HWDGS). Target BW at harvest was 591 kg±23 kg with 121 steers harvested on day (d) 161 and 117 steers on d 224. Hot carcass weight and liver abscess scores were recorded on d of harvest. Longissimus muscle area, rib fat thickness, marbling score, and kidney, pelvic and heart fat were measured after a 24 h chill. No significant differences were observed between treatments regarding average daily gain (ADG) or BW. Steers fed 0 HWDGS had significantly lower average daily feed intake (ADFI) than steers fed HWDGS and the response was quadratic at lower ADFI. Steers fed 70 HWDGS had lower (P<0.05) dry matter intake (DMI) compared to steers fed lower HWDGS concentrations. Steer gain to feed ratio (G:F) was significantly higher for steers fed 70 HWDGS compared to 0, 25, or 40 HWDGS with a quadratic response at higher % HWDGS diets. Mean United States Department of Agriculture (USDA) quality grade was average choice. Mean USDA yield grade was 3.0. Steers fed 70 HWDGS had significantly smaller rib eye areas and a linear trend (P=0.08) to have lower USDA quality grades compared to steers fed lower HWDGS inclusion rates. Increasing dietary HWDGS increased polyunsaturated fatty acid (PUFA) and PUFA/saturated fatty acid concentrations in intramuscular fat with both a linear and quadratic effect. High fat modified WDGS can be fed up to 70% of diet DM without compromising feedlot performance, carcass characteristics, or meat quality.     

Investigating design and provision of access facilities as a barrier to woodland use

A key policy objective of many European Governments and their forestry departments is socially inclusive use of woodlands as use is a pre-requisite to enjoying many of the benefits afforded by woodland. However, access to woodlands is unequally distributed across British society and research suggests disconnect between the facilities provided and their suitability-for-use, given the wide range of reasons for visiting woodland. This research sought to inform woodland management and complement research into barriers to accessing woodland by investigating whether the design and provision of core access facilities may preclude certain user-groups. The research was carried out on the public forest estate of England; although the results are applicable to any woodland where public access is encouraged. The generic findings are applicable also to other greenspace types. Preferences in design were strongly influenced by the instrumentality (functionality) and aesthetic of an item – whether it was in-keeping with the woodland setting. Facility provision and upkeep are also important to woodland users. The study suggests that small changes in facility provision, including greater emphasis on naturalistic and rustic designs, provision of a range of pathway surface types and reducing the urbanisation of woodland, could increase the appeal of woodland to a wider demographic. Woodlands can fulfil a wide range of social functions. Where this is desirable, the woodland (new or existing) should be appropriately designed to reflect these intended roles and functions. This will require a range of facilities sympathetically provided.     

The influence of systematic micro-environmental variation on individual plant yield within selection plots

Summary Moving average and polynomial response surfaces were used to estimate systematic micro-environmental variation within four different F₃ selection environments. At low density the response surfaces were efficient in estimating systematic variation. At high densities random variation due to intergenotypic competition predominates. It is concluded that the two major factors rendering single plant selection for yield inefficient are competition within selection plots and genotype-season interactions between the selection and test generations.