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Simple Summary Sheep are often transported in cold conditions. Some of the coldest exist in northern China and we tested the effects of transporting sheep in these conditions. In order to find out how to limit any of the cold temperatures’ adverse effects, we tested journeys of two durations, in covered and open trucks, and investigated the effects of feeding sheep before transport. We found that sheep had less evidence of cold stress in a covered vehicle. Longer journeys actually allowed the sheep to warm up, but sheep appeared more stressed after the long journeys. Feeding the sheep before transport also helped to ameliorate the adverse effects of cold stress. Abstract Low temperatures can provide a risk to the welfare of sheep during transport because of increased ventilation chilling the sheep, and we examined the importance of three factors—covering the vehicle, duration of transport, and feeding prior to transport—on the welfare of sixty transported 4-month-old Dorper × Mongolian female sheep in a cold climate. Sheep in a covered vehicle had greater increases in head and ear temperatures than those in an open vehicle. Sheep transported for 2 h increased their leg temperatures, whereas those transported for 1 h had reduced leg temperatures. Increases in non-esterified fatty acids (NEFA) and lactate dehydrogenase (LDH) in the blood samples during the long transport suggested that sheep had more muscular and metabolic activity, compromising their well-being. Feeding prior to transport did not affect body temperatures, but those not fed prior to transport had reduced alanine transferase, HSP and cortisol in their blood, whereas those that were fed had reduced NEFAs, LDH and creatine kinase. Prior feeding had no effect on the sheep temperature indices over a two-hour transport period. Thus, the sheep most at risk of the adverse effects of cold temperatures were those transported in open vehicles, those transported for a longer time, and those not fed before transport.

Simple Summary Antibiotics are commonly added to the diet of chickens grown for meat to reduce bacterial contamination of their gastrointestinal tract. The bacteria reduce the efficiency of feed utilization and, hence, growth. However, there are concerns about the inclusion of antibiotics in the feed of chickens grown for meat, because of the development of resistance in the bacteria. As a result, scientists are searching for alternative feed additives. Turnip extract is known to have antibacterial properties but has not been tested in the diet of broiler chickens. We tested several levels of turnip extract in the water for chickens and compared their growth and the level of bacterial contamination of their gut with that of chickens given a standard antibiotic. Although chickens with the highest level of turnip extract initially had slow growth, those given a medium level of turnip extract had faster growth overall, better feed conversion, fewer Gram-negative lactose bacteria in their cecum and fewer antibodies in their blood, compared with those fed the antibiotic. This suggests that inclusion of turnip extract in the diet of chickens could provide an alternative to conventional antibiotics. Abstract There are concerns about inclusion of antibiotics in the feed of broiler chickens, because of the development of antibiotic resistance, leading to a search for alternative feed additives. Turnip extract is known to have antibacterial properties but has not been tested in the diet of broiler chickens. We allocated 200 broiler chicks to receive one of four levels of turnip extract in their water, 0, 150, 300 or 450 ppm, or a standard antibiotic, Virginiamycin, over a 42-day growing period. Although initially there were detrimental effects of providing 450 ppm, overall the 150 ppm level of supplementation increased weight gain, compared with birds given Virginiamycin, and decreased gizzard weight. Birds given 150 ppm or Virginiamycin had increased low-density lipoproteins (LDLs) and reduced very low-density lipoproteins (VLDLs) in their blood serum and reduced antibody responses to sheep red blood cells, compared to birds in the 450 ppm treatment. Birds given turnip extract at 450 ppm had fewer Gram-negative lactose and coliform bacteria than those provided with no turnip extract, and those provided with 150–300 ppm had the same as those provided with Virginiamycin. Turnip extract could potentially replace antibiotics included in the feed of broiler chickens for growth promotion and the control of bacterial infection of the gastrointestinal tract.

Major macronutrient concentrations (K, Ca, Mg, Na, P, and S) and element ratios were determined in 140 Hungarian mono-floral honey samples (acacia, linden, sunflower, rape, chestnut, forest, silk grass, and facelia) by inductively coupled plasma-optical emission spectrometry (ICP-OES). One-way ANOVA (LSD and Dunnett T3 test) and linear discriminant analysis (LDA) were used to determine the botanical origin based on the element content and element ratio of different honey types. Analysing six element concentrations in the honeys of different botanical origin with LDA allowed the botanical origin of 96% of honeys to be predicted. Reducing the examined elements to K, Mg, and Na increased the accuracy of predictions, but it was still not possible to distinguish acacia and facelia honeys. However, examination of element ratios showed that K/Na and K/Mg ratios were able to separate every honey type from each other with 100% cross-validation. It is concluded that using macro-element ratios rather than macro-element concentrations, it is possible to precisely discriminate the floral origin of honey samples.

Mining noise has a wide variety of frequency spectra and is a potential source of stress for wildlife. We evaluated the effects of mining machinery noise on behaviour and associated physiological parameters at two isoenergetic frequency ranges: high (>2 kHz) and low (≤2 kHz), the latter being less audible to mice, our model species. Effects of these two frequency spectra on behaviour, organ morphology and faecal corticosterone of wild mice were compared with a control treatment with no extra auditory stimuli. The mice exposed to high frequency noise spent less time in their nest than those exposed to low frequency noise or those in the control treatment, and they spent more time circling, especially anticlockwise, which in conjunction with elevated faecal corticosterone levels may reflect a greater right brain hemisphere stress-related response, particularly in females. Low frequency mining noise reduced grooming and circling, suggesting decreased physiological arousal due to mild stress. Low frequencies were also associated with increased faecal corticosterone in males compared to controls, which may be related to gender-based differences of the ear canal that affect frequency sensitivity. In conclusion, high frequency and low frequency mining machinery noise produced stress-related responses that may be important for the animals’ welfare and survival.

Ammonia, high temperature and high humidity have adverse effects on animals during long distance livestock export from Australia to the Middle East, but none of these is effectively measured currently. On the basis of data maps obtained on two voyages of live sheep export, this study determined sampling strategies for ammonia, temperature and humidity measurement on the vessel. The difference between predicted high and low ammonia sites on the shipment could be detected with approximately 5 measurement sites of each. Margins of error were determined, which suggested that dry bulb temperature could be measured with 6–8 measurement sites, but even 20 measurement sites were not sufficient to measure relative humidity. For the vessel recorded, considerably more ammonia measurement sites are required on closed decks than on open decks, with less variation for temperature measurement. The number of pens measured contributed more to the variance of ammonia and temperature measurement than the number of sampling locations within each pen on open decks. This study highlights the importance of a suitable sampling strategy to measure ammonia, temperature and relative humidity on board ship during live export.

Detection of soil element deficiencies is time consuming, requiring a major commitment for field work and analysis. Bees concentrate some elements in their honey which could allow soil element concentrations to be predicted without having to take large numbers of soil samples. We measured 14 element concentrations in soil, sunflower, acacia flower and honey samples from two different regions of Hungary. Across sites, the elements with significant correlation coefficients between honey and soil concentrations, in descending order of probability, were Cu > Ba >Sr = Ni > Zn > Mn = Pb >As. Bioconcentration from soil to honey was similar for areas with acacia and sunflower flowers. In the macroelements, it was the greatest for K, S and P and least for Mg and Na, and in the microelements, greatest for B, then Zn, then Cu, then As, Mo and Sr and least for Fe, Ba, Mn and Pb. It is concluded that in acacia and sunflower-growing regions, honey can give an accurate estimate of soil element concentrations for Cu and Ba and provides relevant information for Sr, Ni, Zn, Mn, Pb and As.

Simple Summary We designed a programme to control free-ranging kangaroos on a Queensland golf course, using contraceptive implants in females and vasectomisation or testicle removal in males. This reduced the numbers of pouch young to about one half of pre-intervention levels and controlled the population over a 2–4 year period. However, the necessary darting caused a mortality rate of 5–10% of captured animals, mainly due to complications before and after anaesthesia. It is concluded that population control is possible but careful management of kangaroos around the time of anaesthesia induction and recovery is important in such programmes to minimise losses. Abstract Traditionally, culling has been the expedient, most common, and in many cases, the only tool used to control free-ranging kangaroo populations. We applied a reproductive control program to a population of eastern grey kangaroos confined to a golf course in South East Queensland. The program aimed to reduce fecundity sufficiently for the population to decrease over time so that overgrazing of the fairways and the frequency of human–animal conflict situations were minimised. In 2003, 92% of the female kangaroos above 5 kg bodyweight were implanted with the GnRH agonist deslorelin after darting with a dissociative anaesthetic. In 2007, 86% of the females above 5 kg were implanted with deslorelin and also 87% of the males above 5 kg were sterilised by either orchidectomy or vasectomy. In 2005, 2008 and 2009, the population was censused to assess the effect of each treatment. The 2003 deslorelin program resulted in effective zero population growth for approximately 2.5 years. The combined deslorelin–surgery program in 2007 reduced the birth rate from 0.3 to 0.06%/year for 16 months, resulting in a 27% population reduction by November 2009. The results were consistent with implants conferring contraception to 100% of implanted females for at least 12 months. The iatrogenic mortality rates for each program were 10.5% and 4.9%, respectively, with 50% of all mortalities due to darting-related injuries, exertional myopathy/hyperthermia or recovery misadventure. The short term sexual and agonistic behaviour of the males was assessed for the 2007 program: no significant changes were seen in adult males given the vasectomy procedure, while sexual behaviours’ were decreased in adult males given the orchidectomy procedure. It is concluded that female reproduction was effectively controlled by implantation with deslorrelin and male reproductive behaviour was reduced by orchidectomy, which together achieved population control.

The microclimate can potentially impact the health and welfare of livestock exported by ship. Within-pen microclimatic conditions were recorded and the effects of ammonia on sheep behavior investigated on a voyage from Australia to the Middle East. Ammonia, carbon dioxide, and hydrogen sulfide as well as wet-bulb, dry-bulb, and dew-point temperature and air speed were mapped in 20 open-deck focal pens, with the focus on the behavior and location of a marked sheep in each pen. Air speed was highly variable in most pens, with pockets of high but transient concentrations of ammonia (30.7 to 44.2 mg/m) in 20% of pens that had no or minimal air flow. Carbon dioxide concentrations varied in some pens, but overall concentrations of carbon dioxide and hydrogen sulfide were low. Sheep in pens previously identified to have high ammonia concentrations, high wet-bulb temperatures, and low wind speed stood longer (P = 0.003) and spent less time feeding (P = 0.01) and ruminating (P = 0.004) than those in pens previously identified with low ammonia, low wet-bulb temperature, and high wind speed. Moreover, sheep exposed to increased ammonia concentrations held their head higher (P = 0.004) to avoid the greater ammonia concentrations at lower heights, and these sheep had more conjunctivitis (P < 0.001). Sheep movement around the pen was limited. Increased time spent lying down (P = 0.04) and more rhythmical behavior in the second half of the voyage indicated that the sheep adjusted to shipboard conditions over time. It is concluded that high, transient concentrations of ammonia existed in some pens, which adversely affected the behavior of sheep.

Monthly and seasonal variations among dietary, blood and milk parameters and their interrelationships were investigated during the lactation period in Holstein dairy cows in order to determine reliable dietary indices that could be useful in the studies related to milk yield improvement. Samples were prepared monthly, up to 11 months of lactation and were analyzed by the current laboratory methods using appropriate kits. Mean monthly and seasonal comparison of the dietary, blood and milk values were different among sampling times (p

The avoidance of ammonia by sheep was tested using operant conditioning techniques, training 12 sheep to operate a lever to open a door that would allow them to traverse a chamber with or without ammonia and obtain a food reward. One half of the sheep had been previously exposed to ammonia at 45 ppm in a simulated ship voyage, and the other half were kept in identical conditions but without ammonia. The maximum number of lever presses, or breakpoint, achieved when the chamber contained 45-ppm ammonia was compared with the number when the chamber contained no ammonia. There was a significantly lower mean breakpoint when the sheep traversed the chamber filled with ammonia (mean: 4.2 presses), compared with the chamber filled with fresh air (mean: 6.6 presses), demonstrating that sheep exhibited a moderate aversion to 45-ppm ammonia. Although the scale of the reduction in mean breakpoint was considerable, the aversion was only clearly demonstrated in 75% of the sheep, and there was no evidence that prior exposure influenced this aversion. It is therefore concluded that sheep show a moderate aversion to 45-ppm ammonia, with no evidence of sensitivity being affected by previous exposures.

Urea is a common ingredient of the diets of intensively fed lambs, but is increasingly required for industrial processes. Maize steep liquor (MSL) is a by-product of maize grain degradation to produce starch that may be a suitable replacement. Fifty growing lambs were fed on equinitrogenous diets in which between 0% and 80% of the urea was replaced by MSL; their growth and metabolism were recorded over 70 days. Increasing replacement of urea by MSL increased feed intake and nutrient digestibilities, leading to increased growth rates, more efficient feed conversion, and increased nitrogen retention. Concentrations of triiodothyroxin, thyroxin, glucose, and methionine were increased by replacement of urea by liquor, and plasma urea was reduced. This study suggests that MSL is a suitable replacement for up to 80% of urea in the diet of rapidly growing lambs.

The duration of exposure of sheep to dietary Pb may affect their ability to manage the toxic effects of the Pb, as well as influencing the metabolism of other heavy metals. Sheep were exposed to a supplement of 34 mg Pb/kg basal diet DM for 3, 6 or 9 weeks. Compared with 3-week exposure, rumen contents after 6 weeks had increased Pb content (P = 0.02), and after 9 weeks had reduced Cu (P = 0.01) and Cr (P = 0.04) concentrations. The longer exposure periods reduced digestion of long particles, and increased the alkali buffering potential in the rumen, but duration of exposure to Pb did not affect its proportional absorption (P = 0.26). Most additional Pb was excreted in faeces or accumulated in the bones and spleen, and urinary Pb output was increased (P < 0.01) after exposure for 6 or 9 weeks. Proportional absorption of Cd was increased after 6 and 9 weeks of Pb exposure, compared to 3 weeks (P < 0.01), and after 6 weeks renal Cd had increased from 4 to 9 mg/kg (P < 0.01), which is above the normally accepted legal maximum concentration of 4.8 mg/kg. After 9 weeks of Pb exposure Cd had declined in the kidney and increased in blood cells. It is concluded that duration of exposure to Pb did not affect its absorption, and there was no evidence of protective mechanisms, but extended exposure caused increased accumulation of Cd that rendered renal concentrations above legal limits.

Ammonia can accumulate in high-density cattle accommodation during live export shipments and potentially threaten the health and welfare of the animals. The effects of 4 NH(3) concentrations, control (6), 11, 23, and 34 mg/m(3), on the physiology and behavior of steers were recorded. The animals were held for 12 d under a microclimate and stocking density similar to shipboard conditions experienced on voyages from Australia to the Middle East during the northern hemispheric summer. In bronchoalveolar lavage samples, ammonia increased (P0.05) macrophage activity in proportion to NH(3) concentration and increased (P0.05) neutrophil percentage at 23 and 34 mg/m(3), indicating active pulmonary inflammation. Ammonia also increased (P0.05) lacrimation, nasal secretions, and coughing, particularly at 34 mg/m(3), indicating that the NH(3) was irritating the mucous membranes of the eyes, nasal cavity, and respiratory tract. Ammonia had no effect (P0.05) on hematological variables or BW. Twenty-eight days after exposure to NH(3), the pulmonary macrophage activity and neutrophil concentrations of the steers had returned to normal. It was concluded that ammonia concentrations of 23 and 34 mg/m(3) induced temporary inflammatory responses, which indicate an adverse effect on the welfare of steers.

Background: Cadmium accumulates in sheep tissues and often approaches the legal limit for human consumption in kidneys. Previous models have focused on transfer from plants to sheep but have restricted value due to seasonal and species variation in plant cadmium concentration. We created a model for the accumulation of cadmium in sheep using empirical relationships previously derived for accumulation in sheep kidney and liver from feeds, together with equations for accumulation in feeds derived from soil characteristics. The combined model relates soil cadmium to liver and kidney concentrations. Results: Sensitivity analysis demonstrated that the kidney accumulated cadmium faster than the liver and the greatest influence was the total cadmium concentration in the soil. The weight gain of the sheep and soil pH where the feed was grown had relatively minor influences on cadmium concentration in liver or kidney. Conclusion: A combined model of soil, plant and sheep kidney and liver characteristics enables concentrations of cadmium in sheep liver and kidney to be predicted from soil characteristics. This will enable the long-term risks of specific sites to be predicted with greater accuracy than if just plant cadmium concentrations were utilized.

This paper identifies different length scales λs for strain-reducing chemical bonding self-organizations (CBSO) in non-crystalline and nano-crystalline thin films. CBSOs are differentiated spectroscopically, and explained by semi-empirical bond-constraint theory (SE-BCT). Non-crystalline thin film CBSOs are characterized by molecular scale, strain-reducing chemical ordering with λs > 0.6 nm, and extending to at most 1 nm. The non-random bonding results in reduced defect densities that are enabling for device applications. Nano-crystalline transition metal oxide thin films display qualitatively different properties in two distinct nano-scale regimes in which the length scale metric is defined by π-bond coupling between atoms in strings of neighboring primitive unit cells (PUCs): (i) type I with nano-grain dimensions and λs ∼ 2 nm (or 3–4 nm (>6 PUCs). There are also diphasic nano-crystalline/non-crystalline technologically important thin films in which strain percolation is also minimized by CBSOs that combine molecular and PUC scales of order. Representative non-crystalline, nano-crystalline and diphasic nano-crystalline/non-crystalline thin film materials with qualitatively different behaviors and degrees of phase stability/metastability are addressed.

This paper presents a discussion of intermediate phases in thin film materials that have been incorporated into liquid crystal displays, LCDs, and optical memory thin film devices. The formation of intermediate phases in the a-Si3N4:H (a-Si:N:H) alloys used for gate dielectrics in thin film transistors, TFTs, of LCDs, and the a-Ge–Sb–Te (GST) alloys used for read-write optical writing and storage in optical memory discs are qualitatively different than those first addressed by the Boolchand group in Ge–Se bulk glass alloys. In the a-Si:N:H and a-GST thin films, the chemical self-organizations that suppress percolation of strain, involve chemically-ordered bonding arrangements that break bond bending constraints at the four-fold coordinated Si and Ge atoms in a-Si:N:H and a-GST, respectively. In the GST alloys, this results in over-coordinated and under-coordinated atomic constituents, or valence alternation pairs, VAPs, of charged defects. Finally, other technologically important systems in which broken constraints, and/or VAP defects are important in intermediate phase formation include group IVB (Ti, Zr and Hf) Si oxynitride alloys, and hydrogenated amorphous Si (a-Si:H).

The ability of free range chickens to detect and select feeds with varying heavy metal concentrations is important in relation to their ability to avoid toxic heavy metals in polluted regions and to self-supplement their diet with nutritive metals. An operant test was conducted to determine whether chickens could detect a range of heavy metals mixed with feed pellets, with seven birds rewarded for selecting feeds with added metals and seven birds rewarded for selecting feeds without added metals. The chickens demonstrated an ability to detect very high levels of iron, copper, and zinc in feed, but they could not detect concentrations typical of polluted regions, that is, 1,500-2,000 mg/kg feed. They also Could not detect the potentially toxic elements cadmium, lead, or selenium at concentrations Just below the level likely to induce toxicity. The chickens were successfully trained to discriminate between three different pairs of colored plates (red/green, black/yellow, and blue/white) and to associate the different pairs of colored plates with food contaminated and uncontaminated with copper, zinc, and iron, respectively, at the maximum concentration which they could detect. Their preference for the contaminated or uncontaminated food samples was then investigated ability and the second preferences. The second method could not have been used to determine discrimination ability, or at least it would have been unnecessary and potentially confusing to involve a colour association. The first method could not easily have been used to determine preferences, because the color association allowed the birds to choose one or other arm of the Y maze before they reached the point of no return. Hence, the method allowed a voluntary choice to be made in the easiest way. Colour association has been used to test chickens' nutritional preferences previously (e.g., Kutlu and Forbes, 1993).

A meta-analysis of existing scientific literature recently suggested that Cd is absorbed more efficiently by sheep if it is in the organic form in grass, than if it is added as an inorganic supplement to the diet. We tested this experimentally by feeding sheep grass from contaminated soil, compared with uncontaminated grass and with Cd added to the diet. To produce contaminated herbage, Cd nitrate was added to soil in 11 lysimeters sown with perennial ryegrass, with a further 11 lysimeters receiving no Cd to produce uncontaminated herbage. In the Cd-treated lysimeters, soil had increased exchangeable K, Mg, and Ca, leachate had increased K, Mg, Ca, Na, and P, grass had increased Cd and reduced Mg, Na, P, Mn, Fe, Cr, Al, and Ni, and there was some reduction in grass yield compared with untreated lysimeters. Grass from Cd-treated or untreated lysimeters was fed to groups of 12 ewes for 2 days, with Cd intake equated by adding Cd nitrate to the concentrate feed of ewes receiving the uncontaminated grass. The apparent absorption of Cd, Zn, Mo, Cr, and Al was increased for ewes receiving Cd-enriched grass, and apparent absorption of Cu was reduced, compared to those receiving supplementary inorganic Cd. Most of the unabsorbed Cd was excreted in feces within 4 days of feeding. The ewes consuming Cd in grass had increased B concentrations in their urine, possibly due to adverse effects of Cd on kidney function. Finally, the ewes were offered a choice of the two herbages and they ate significantly more of the uncontaminated grass. It is concluded that the apparent absorption of Cd and other heavy metals by sheep in a short-term experiment was greater when Cd was in the grass than when the Cd was added in in an inorganic form and that sheep partially avoided herbage with a high Cd concentration.

The complexity and functionality of proteins requires that they occupy an exponentially small fraction of configuration space (perhaps 10?300). How did evolution manage to create such unlikely objects? Thorpe has solved the static half of this problem (known in protein chemistry as Levinthal's paradox) by observing that for stress-free chain segments the complexity of optimally constrained elastic networks scales not with expN (where ?1000 is the number of amino acids in a protein), but only with N. Newman's results for diffusion in N-dimensional spaces provide suggestive insights into the dynamical half of the problem. He showed that the distribution of residence (or pausing) time between sign reversals changes qualitatively at . The overall sign of a protein can be defined in terms of a product of curvature and hydrophobic(philic) character over all amino acid residues. This construction agrees with the sizes of the smallest known proteins and prions, and it suggests a universal clock for protein molecular dynamics simulations.

The effects of feeding Cd to sheep at a level that is typical of polluted regions were investigated, as well as possible amelioration by adding Zn to the diet. Welsh Mountain ewes (n = 24) were fed herb-age and concentrate in metabolism crates, with four supplement treatments in a two-factor factorial design: no supplement, Cd supplement only, Zn supplement only, and a combination of both the Cd and Zn supplement. Cadmium (286 microg/kg of feed DMI) and Zn (8.6 mg/kg feed DMI) were added as sulfates. Food and water intakes and element balances were recorded over 20 d after 7 d dietary adaptation, and element concentrations were determined in wool samples. Neither metal affected DMI or digestibility (P > 0.15), but water intake (P = 0.001) and urine output (P = 0.03) were decreased when only the Zn supplement was added. Water retention was increased by the Cd supplement (P = 0.04). In wool, the Cd supplement greatly increased the K concentration if no Zn supplement was fed (P = 0.02), and the Zn supplement decreased Mn concentration (P = 0.02). Cadmium in feed increased the Cd balance and produced several mineral disturbances, in particular a decrease in Na balance that is typical of renal tubular disorders. Adding Zn as well as Cd to feed returned the Cd balance to a level similar to that of sheep receiving neither Cd nor Zn, which suggests that Zn status is critical in determining whether Cd in feed increases the Cd balance in sheep. Feeding Cd also increased urinary K, Fe, Mo, Cr, B, and Ca concentrations, even when supplementary Zn was fed. It is concluded that low levels of Cd in sheep feed can increase the Cd balance if adequate Zn is not provided, which can lead to subclinical mineral disturbances and changes in the mineral concentrations in wool.

Linear regression of published values for soil parameters and cadmium concentrations in plant tissues offers the opportunity to develop uptake coefficients that can be applied in a wide range of circumstances. A widespread literature search was performed which identified publications from the last 20 years containing information on cadmium uptake by maize and rye grass plants. After discarding experiments with inadequate data or parameters, 10 and eight papers were chosen for maize and rye grass respectively to develop linear models that related pH and cadmium concentration in the growth media (soil in pots or nutrient solution) to cadmium concentration in maize or rye grass plants (excluding roots). Cadmium concentrations in both maize and rye grass were positively correlated with soil cadmium concentration, and in the case of maize negatively correlated with soil pH. They were also negatively correlated with the product of soil cadmium concentration and soil pH, demonstrating that at high soil cadmium concentration a high soil pH reduced plant cadmium concentration. A further model of data generated from one experiment with soya beans demonstrated that other factors, such as soil temperature, can have a major influence on uptake. (C) 2004 Society of Chemical Industry.

Fourier transform scanning tunnelling microscopy (STM) on Bi2Sr2CaCu2O8+ δ (BSCCO) subgap resonances has deciphered an octet of ‘quasiparticle’ states that are consistent with the Fermi surface and energy gap observed by angle-resolved photoemission spectroscopy (ARPES), but the origin of the high-intensity k-space octets and the sharply defined r-space chequerboard is unexplained. The filamentary ferroelastic nanodomain model that predicted the r-space chequerboard also explains the k-space octets and the origin of the apparent anisotropic surface d-wave gap by using strong electron–phonon interactions outside the CuO2 planes. The topological model identifies the factors that stabilize high-intensity k-space octets in the presence of a very high level of irregular r-space chequerboard noise.

Limits for cadmium and lead concentrations in food animal products have been established independently, whereas these two toxic metals often co-exist in polluted regions. Weaned pigs (60) were allocated to ten treatments: control; low (0.5 mg kg(-1)), medium (1 mg kg(-1)) or high cadmium (2.5 mg kg(-1)) in feed; low (5 mg kg(-1)) medium (10 mg kg(-1)) or high (25 mg kg(-1)) lead in feed; and low, medium and high cadmium plus lead in feed. Growth rates and concentrations of cadmium and lead in body tissues (kidney, liver, spleen, lungs, heart, testicle, ribs, hair and teeth) were measured after 137 days. There was a similar reduction in weight gain for pigs in the cadmium and lead treatments, compared with the control, and a greater reduction for the pigs in the cadmium plus lead treatments. The reduction increased with the level of metal included. There was an increase in cadmium concentration of all tissues and blood with increasing feed cadmium concentration, which was usually less when lead was also included in the feed. There was also an increase in tissue lead concentration with increasing dietary lead, and this was in most cases increased when cadmium was also included in the feed. The most sensitive tissues for cadmium and lead exposure were the kidney, liver, hair and teeth, and regression equations were developed for the accumulation rates in these tissues. Tissue and blood cadmium concentrations increased gradually with increasing dietary lead, whereas tissue lead concentration was not sensitive to dietary cadmium, except in the ribs and heart. In a second experiment, 10 sows were allocated to a control diet or the same diet but with a supplement of cadmium and lead. The birth weight of piglets was decreased by the supplement and their mortality increased. Lead accumulated most in the ovary and oviduct of the sows, and there were increases in the lead and, to a lesser extent, cadmium concentrations of tissues of the piglets from these sows. (C) 2003 Society of Chemical Industry.

An increased sodium appetite has been demonstrated in cattle following supplementation with sodium in the neonatal period, but it is unclear whether the sodium appetite of calves can be influenced in utero by the dam’s sodium intake during pregnancy. Twenty-two non-lactating, pregnant dairy cows received either a diet of silage and concentrates or the same diet with 70 g NaCl per day added to it for the last 2 months of pregnancy. The sodium supplement increased the birth weight of their calves but after 6 weeks there was no difference between treatments in calf weight. In addition to milk, calves in both treatments were offered a choice of concentrates with normal or high sodium concentrations (5·8 and 10·8 g/kg dry matter, respectively). Calves from the cows that had received supplementary sodium during pregnancy ate more of the high sodium concentrate than calves from cows without the sodium supplement, demonstrating that sodium appetite could be entrained by the sodium intake of the dam during late pregnancy.

Lead from industry, and vehicles in some countries, can contaminate cattle pastures. We determined the concentrations of lead on herbage that cows can detect. Four cows were trained in a four-lane maze to detect an herbage sample that was superficially contaminated with 240 mg Pb/kg from three uncontaminated samples, and four were trained to detect an uncontaminated sample from three contaminated samples. Pb concentrations were reduced until the cows could not discriminate between samples, which occurred at 30 to 60 mg/kg. In a second experiment, 12 cows were allocated to two groups that grazed either pasture with added Pb (86 mg/kg) or pasture with no added Pb for 4 wk. Lead reduced grazing time and pasture biting rates, leading to an increase in herbage height. Immediately afterwards, these cows were grazed for 4 wk on a mosaic of 18 plots with no added lead, a low Pb level (67 mg/kg), or a high Pb level (102 mg/kg) (Experiment 3). Lead reduced grazing time and pasture biting rate, particularly at the high level. Plots without added Pb were grazed to the shortest height, and plots treated with Pb at 102 mg/kg were tallest. Prior exposure to Pb increased grazing time, especially on the high Pb level, and it increased the rate of biting pasture without Pb. To understand these phenomena, herbage samples from Experiments 2 and 3 were incubated in rumen liquor and artificial saliva, and gas production was measured over 48 h. In both experiments, the application of Pb reduced the rate of gas production or total gas production. It is concluded that cows can detect Pb on herbage, that it reduces their grazing time and pasture biting rate, and that they prefer to graze pasture without Pb. The aversion to Pb on pasture, which may be due to adverse effects on ruminal digestion, diminishes over time.

Ellipsometric synchrotron spectroscopy of YBCO provides persuasive evidence supporting the Phillips-Jung (PJ) filamentary nanodomain model of the electronic structure of high-temperature superconductors (HTSCs). The PJ model is part of a universal off-lattice topological platform that explains the origin of the intermediate phase that is responsible for high-temperature superconductivity, the stiffness transition and reversibility window in network glasses, and the folding transitions of proteins. In HTSCs it is both more specific and more general than descriptions based on conventional collective modes related to charge-density waves.

Filamentary high-temperature superconductor (HTSC) theory differs fundamentally from continuous HTSC theories because it emphasizes self-organized discrete dopant networks and does not make the effective-medium approximation. Analysis of neutron and infrared (especially with c-axis polarization) vibrational spectra, primarily for YBa2Cu3O6+x, within the filamentary framework, shows that the observed vibronic anomalies near 400 cm−1 (50meV) are associated with curvilinear filamentary paths. These paths pass through the cuprate chains and planes, as well as resonant tunnelling centres in the BaO layers. The analysis and the data confirm earlier filamentary structural models containing ferroelastic domains of diameter 3–4 nm in the CuO2 planes; it is these nanodomains that are responsible for the discrete glassy nature of both electronic and vibrational properties. Chemical trends in vibronic energies and oscillator strengths, for both neutron and photon scattering, that were anomalous in continuum ...

What is the microscopic interaction responsible for high temperature superconductivity? Here data on temporal relaxation of T c and the room temperature conductivity in YBa2Cu3O6+x after abrupt alteration by light pulses or pressure changes are analysed. The analysis proves, independently of microscopic details, that only electron-phonon interactions can cause high-temperature superconductivity in the cuprates; all other dynamic interactions are excluded by experiment.

The concentrations of nitrate and potentially toxic elements (PTEs) are reported in water leached from a perennial ryegrass pasture to which isonitrogenous quantities of sodium nitrate, ammonium nitrate or ammonium sulphate fertilisers had been applied in an experiment lasting 2 years. The experimental design allowed a comparison of the immediate effects of sodium nitrate in the grazing season in which the fertiliser was applied with the residual effects of applying it in the previous year. Leachate composition was monitored from December of the first year to August of the second year. Sodium fertiliser reduced the concentrations of cadmium in soil and leachate, but it increased lead concentration in soil and reduced it in leachate. Sulphur fertiliser had no effect on any PTE. Nitrate concentration in leachate increased towards the end of the winter to almost reach the EU legal limit in water and then declined during the spring and summer. Sodium fertiliser applied in either but not both years reduced nitrate concentration. Sulphur fertiliser had varied effects on nitrate concentration in leachate depending on the timing of sodium fertiliser application. When applied at the same time as sodium fertiliser, sulphur fertiliser decreased nitrate concentration, but when applied to areas that had received sodium fertiliser in the previous year, it increased nitrate concentration. It is suggested that sodium fertiliser residues may have long-term effects on leachate nitrate concentration that determine the impact of sulphur fertilisers. It is concluded that sodium fertilisers may reduce the concentrations of at least two PTEs, cadmium and lead, in ground water and that the effects of sulphur fertilisers are dependent on the sodium status of the soil. (C) 2002 Society of Chemical Industry.

Objectives: To estimate exposures to cadmium (Cd) received by the United Kingdom population as a result of the dispersion of zinc Cd sulfide (ZnCdS) by the Ministry of Defence between 1953 and 1964, as a simulator of biological warfare agents. Methods: A retrospective risk assessment study was carried out on the United Kingdom population during the period 1953-64. This determined land and air dispersion of ZnCdS over most of the United Kingdom, inhalation exposure of the United Kingdom population, soil contamination, and risks to personnel operating equipment that dispersed ZnCdS. Results: About 4600 kg ZnCdS were dispersed from aircraft and ships, at times when the prevailing winds would allow large areas of the country to be covered. Cadmium released from 44 long range trials for which data are available, and extrapolated to a total of 76 trials to allow for trials with incomplete information, is about 1.2% of the estimated total release of Cd into the atmosphere over the same period. ''Worst case'' estimates are 10 mug Cd inhaled over 8 years, equivalent to Cd inhaled in an urban environment in 12-100 days, or from smoking 100 cigarettes. A further 250 kg ZnCdS was dispersed from the land based sites, but significant soil contamination occurred only in limited areas, which were and have remained uninhabited. Of the four personnel involved in the dispersion procedures (who were probably exposed to much higher concentrations of Cd than people on the ground), none are suspected of having related illnesses. Conclusion: Exposure to Cd from dissemination of ZnCdS during the ''cold war'' war" should not have resulted in adverse health effects in the United Kingdom population.

The element composition of water leached from a perennial ryegrass pasture to which isonitrogenous quantities of sodium nitrate, ammonium nitrate or ammonium sulphate fertilisers had been applied in an experiment lasting 2 years is described. The experimental design also allowed a comparison of the immediate effects of sodium nitrate in the grazing season in which the fertiliser was applied with the residual effects of applying it in the previous year. Applying sodium fertiliser in either 1992 or 1993, but not both years, increased the concentrations of sodium, potassium, magnesium, calcium and cobalt and reduced those of phosphorus and molybdenum in leachate. The application of sulphur fertiliser reduced the concentrations of zinc, copper, iron and molybdenum in leachate. It also reduced the concentrations of sodium, potassium and magnesium, but only when sodium fertiliser was applied in 1992, and not when it was applied in 1993. It is concluded that sulphur fertiliser reduces the leaching of trace elements from the soil and that, in the long term, sodium fertiliser can amplify the effect of applying sulphur fertiliser. Sodium fertiliser in moderate quantities increased the leaching of the major divalent cations but reduced the phosphorus and molybdenum concentrations in leachate. (C) 2002 Society of Chemical Industry.

In many oxides of the perovskite and pseudoperovskite families there are phase transitions between insulating and normal metallic (Fermi-liquid) phases that are separated by an intermediate phase that is often called a non-Fermi liquid. The dc resistivity of the intermediate or non-Fermi-liquid phase often exhibits a T temperature dependence, in contrast with the T2 dependence expected from a bad normal metal. The same alloys exhibit a non-Drude w2a frequency dependence, with α ≈ 0.5, in contrast with the Drude dependence w2 characteristic of samples with the T2 behaviour. Various attempts have been made to modify the algebra of continuum Fermi-liquid theory to derive the non-Drude exponent α, but these have been based on artifices designed to explain only this one parameter. The discrete filamentary model has been used to calculate many properties of high-temperature superconductors, and to explain the asymmetric nature of the intermediate phase. Here it is used to derive N by the same rules pre...

In two similar experiments, Lablab purpureus was sown at different dates in July and August to evaluate the effects of sowing date on the yield and nutritive value of the plant and shed leaves. On each occasion, an interim harvest was performed on half of the plants sown at each date and the regrowth recorded. The interim harvest reduced the total yield, and in particular that of shed leaves. In one of the two experiments, late sowing resulted in a considerable reduction in yield, increased crude protein and reduced modified acid-detergent fibre concentrations. Ash concentrations were higher in plants sown later and their shed leaves. Sodium concentrations were inadequate for ruminants and, like phosphorus concentrations, tended to decrease with later sowing. However, both calcium and magnesium concentrations increased with later sowing and were sufficient for ruminant production. Potassium concentrations were high and were little affected by sowing date. It is concluded that both an interim harvest and late sowing are disadvantageous when lablab is grown for ruminant livestock, the former because of yield reduction and the latter because of yield reduction, increases in ash concentration and reductions in sodium and phosphorus concentrations.

Anomalous features (dispersive gaps and pseudogaps) have been observed by inelastic neutron scattering in the longitudinal optical bond-stretching vibrational spectra of superconductive (Ba0.6K0.4BiO3) and ferromagnetic (La1−xSrxMnO3) doped perovskites, as well as in layered superconductive pseudoperovskite cuprates La2−xSrxCuO4 (x = 0.15) and YBa2Cu3O6−x (x = 0.20, 0.35, 0.60 and 0.93). These anomalies are explained by a microscopic theoretical model which is compatible with the only known satisfactory fundamental model of superconductivity, namely the Bardeen–Cooper–Schrieffer theory. The model assumes that the dopants are self-organized into chains and planes with short-range orders of special symmetries.

A high herbage K:Na ratio increases the risk of ruminal tympany in cattle, which may relate to digestion rate. Experiment 1 examined whether in vitro digestibility of ryegrass was affected by NaCl fertilizer or by Na concentration in artificial saliva. Fertilizer Na increased grass digestibility, but Na in artificial saliva decreased it, probably due to the energy cost of sodium exclusion from bacteria. Increased herbage digestibility with fertilizer Na is therefore not due to additional Na, but may relate to increased water-soluble carbohydrates. Experiment 2 examined whether NaCl fertilizer applied at 35 or 70 kg Na ha(-1) to ryegrass and white clover affected in vitro gas production. Sodium fertilizer increased maximum gas output from grass and rate of production, confirming the increase in grass digestibility recorded previously but in clover it had the opposite effect, thereby potentially reducing ruminal tympany in cows fed a high legume diet. (C) 2001 Harcourt Publishers Ltd.

The nature of appropriate microscopic models that can successfully describe anomalous transport properties, such as high-temperature superconductivity and giant magnetoresistance, in carefully selected and optimally processed complex inorganic materials such as doped layered multinary pseudoperovskite oxides is still unclear. This may be caused by lack of recognition, especially by theorists, of the consequences of the fundamental dichotomy between continuous and discrete (or network) systems. The simplest way to determine the generically correct choice of models in such systems may be through scaling experiments associated with connectivity transitions. Here I show that the same approach is equally successful in explaining the origins of metabolic biometric (or allometric) scaling. From this one can conclude that the topological differences between conductivity networks in specially selected complex inorganic materials and circulatory systems of living animals and plants may be far smaller than ...

The distribution of trace elements, toxic metals and water-soluble carbohydrates was examined in the leaves, stems and inflorescences of perennial ryegrass and white clover, with and without sodium fertiliser. Copper and manganese were observed in both species to concentrate in the leaves and stems and iron and molybdenum in the leaves. In clover, nickel concentrated in the inflorescence. Differences in mineral concentrations between fractions were related to the mobility of the metal and its function in the plant. Sodium fertiliser approximately doubled the cadmium content of the leaves, stems and inflorescences of both species, reflecting cadmium mobilisation from the soil. The sodium fertiliser also reduced the zinc, copper, manganese and iron contents of grass but not clover and increased the molybdenum content of clover but not grass. Water-soluble carbohydrates were increased by sodium in grass but decreased in clover. Differences between the two species appeared to relate to nitrogen fixation by clover but not grass. © 1999 Society of Chemical Industry

The effect of mild water stress on the response of herbage grown in sandy or loam soils to sodium nitrate fertilizer has been investigated. Sodium nitrate was applied at the equivalent of 32 kg Na ha−1 to perennial ryegrass and white clover grown in pots with sand, loam and mixed soils and irrigated daily. One half of the pots were subjected to water stress by withholding irrigation water for three days each week. Water stress reduced herbage yield but did not affect the response to sodium fertilizer, except that the ash concentration of grass was increased only when water stress was applied as well as sodium fertilizer. The sodium fertilizer increased herbage sodium concentrations and decreased calcium and magnesium concentrations. It also increased the potassium concentration in clover and in herbage grown in sandy but not loam or mixed soils. Clover and grass had similar sodium and magnesium concentration, but clover contained more nitrogen, potassium and calcium than grass. Therefore, under the conditions of this experiment, the increase in herbage sodium concentration with sodium fertilizer was consistent and not affected by water stress, soil type or herbage species. Changes in herbage potassium concentration, however, were inconsistent, which detracts from the value of sodium fertilizer for reducing hypomagnesaemia in ruminants. © 1999 Society of Chemical Industry

The influence of prior exposure to high salt diets on the salt appetite and the exhibition of stereotyped behaviour patterns was investigated with individually penned calves and tethered dairy cows. In the first experiment one half of a group of 12 calves received concentrates with the sodium content increased from 4 to 9 g/kg by the addition of NaCl up to weaning at 6 weeks, the other half had no supplementary NaCl added to the concentrates. Adding the NaCl increased the food intake of the calves, the time spent ruminating and live weight. Stereotyped behaviour patterns, such as self-grooming, licking the pen or buckets and ear sucking were reduced by adding NaCl. Calves were tested for their salt preference at 6 months of age by adding varying quantities of NaCl to silage. Exposing calves to supplementary NaCl in the concentrate pre-weaning increased the preferred sodium concentration of silage from 3 to 9 g/kg dry matter (DM). In the second experiment 36 tethered dairy cows received either a restricted concentrate and forage diet with a mean dietary sodium concentration of 2 g/kg DM, or the same diet but with the sodium content increased to either 7 or 12 g/kg DM by adding NaCl to the concentrates. There was no effect of NaCl on feeding or ruminating behaviour but the total amount of stereotyped behaviour, including mouthing or rubbing the tethering chain or bars, self-grooming and nosing or pawing the ground, decreased with increasing salt in the diet. It is concluded that increasing the sodium content of the diet of young calves from 4 to 9 g/kg increased their subsequent salt appetite and that increasing the salt content of the diet of calves or cows in restricted housing conditions can reduce the amount of stereotyped oral behaviour.

Powerful new/old experimental evidence supports the filamentary model, for the metal-insulator transition in randomly doped, uncompensated impurity-band semiconductors. The resulting phase diagram, which contains an intermediate ‘X’ phase, closely resembles the usual phase diagram for high-temperature superconductors, leading to the identification of the X phase (which is often called a ‘non-Fernii liquid’) as an anisotropic 3d filamentary metal. An important by-product of the new/old evidence is that it leads to a quantitative, parameter-free estimate of the strength of the dopant electron-ion interaction energies, which in the impurity band case are 25 times larger than those of bonding valence electrons, corresponding to a maximum T c ∼ 150 K. A phase diagram is predicted for an ‘ideal’ high-temperature superconductor which is characteristically different from that currently sketched in experimental papers; observation of such a phase diagram would constitute strong evidence in favour of the f...

Spermatogenesis in five rams that were fed 7.5 mg Cd daily, a quantity typical of levels in the vicinity of a pollution source, was compared with five rams that received no cadmium supplement. Cadmium was added to their concentrate supplement and the rams grazed a perennial ryegrass and cocksfoot pasture. Semen from each ram was collected weekly into an artificial vagina for 7 weeks from days 20–69, a period that was deliberately short to minimise the possibility that effects of cadmium on intake and other physiological processes might indirectly affect spermatogenesis. There were no treatment effects on the spermatozoa concentration in the semen or output per ejaculate, the proportion of live spermatozoa, their progressive linear or vertical motility, wave motion at the periphery of the semen sample or testis circumference. Of 13 different measurements taken of behaviour, cadmium affected only 3; cadmium-treated rams grazed longer, ruminated less and had fewer Flehman responses. Since there were only 5 rams/treatment for a 2-day period, these apparent effects of cadmium on behaviour need to be treated with caution. It is concluded that cadmium concentrations of feed that are typical of a polluted area pose no risk in the short term to spermatogenesis in rams, but there are effects on behaviour that warrant further investigation.

Enthalpies of vaporization for esters covering a molecular weight range of about 74–939 g/mol · [monocarboxylics; linear esters of sebacic series; branched esters of triglyceride series; and, oligomer esters of poly(hexamethylene sebacate)] and a temperature range of about 273.15–523.15 K have been empirically fitted to within about 5% to an equation of the following form: ΔHv(T,M) = S(T)f(M) + I0(T), where S(T) = C Ln(T) + K0, I0(T) = aT + b0, and f(M) = M/(1 + a0M), M is the molecular weight (molar mass); T is in degrees Kelvin; and, C, K0, a, b0, and a0 are constants. These results were used to determine the heat capacity difference, ΔCp = Cp(l) − Cp(g), and compared to calculated values from functional relationships of Cp(l) and Cp(g), l is liquid g is gas. The heat capacity difference results in conjunction with Cp(l) were used to empirically calculate the heat capacity of the gas, Cp(g), over the molecular weight and temperature ranges investigated and compared to a group contribution method. The functional forms for ΔHv(T,M), ΔCp(T,M), Cp(l), and Cp(g) were also found to be applicable for n-alkanes. © 1998 John Wiley & Sons, Inc. J. Appl. Polym. Sci. 70: 731–746, 1998

The effect of sulphur and sodium fertilizers on the response of a perennial ryegrass (Lolium perenne) sward was examined over 2 years. Sulphur fertilizer was applied as ammonium sulphate at 0 or 97·5 kg S ha−1 year−1 and sodium fertilizer as sodium nitrate at 0 (nil), 31 (low), 62 (medium) or 94 (high) kg Na ha−1 year−1, with nitrogen input balanced across all treatments. Both sulphur and sodium increased herbage yield. Sodium fertilizer increased herbage sulphur concentration and sulphur fertilizer slightly increased herbage sodium concentration, but there were no major interactions between the two fertilizers on herbage yield or composition in the season of application. Sodium fertilizer increased dry-matter digestibility, water-soluble carbohydrate concentration and the live proportion of the herbage. Herbage sodium and magnesium concentrations were increased and potassium concentration decreased by sodium fertilizer. Sulphur fertilizer increased herbage dry-matter digestibility and water-soluble carbohydrate concentration. Sulphur and potassium concentrations were also increased and non-protein nitrogen, magnesium and phosphorus concentrations decreased in response to sulphur fertilizer. It is concluded that, although there was evidence of facilitation of sodium uptake by sulphur fertilizer and vice versa, this was not sufficient to produce synergistic effects on herbage growth in the season of application.

Fertilisation of herbage with Na can increase acceptability to cows, but the influence of fertiliser rate and fertilisation by K is unknown. In experiment 1, ten cows were grazed on pasture plots that had just been fertilised with 0-132 kg-Na ha -1 (current Na) and had received 0-64 kg-Na ha -1 in the previous grazing season (residual Na). Herbage Na concentration increased in proportion to current Na from 2.7 to 4.9 g-Na kg -1 dry matter (DM) and also increased with increasing residual Na from 2.2 to 4.5 g-Na kg -1 DM. Herbage K concentrations were low (10 g kg -1 DM at 0 kg-Na ha -1 ) and were only slightly reduced by Na fertiliser. Herbage Mg and Ca concentrations and DM digestibility were maximum at 66-99 kg-current-Na ha -1 . Cows grazed current-Na-fertilised plots to a lower height and spent more time grazing them. In experiment 2, pasture plots received no fertiliser, low and high isomolar and independent applications of Na and K or a combination of the two. The herbage was more mature than in experiment 1 and Na concentration of the herbage without Na fertilizer was high (5 g kg -1 DM). Na fertiliser, therefore, only slightly increased Na concentration, more in clover than in grass, and had little effect on K concentration. K fertiliser increased K concentration from 16 to 20 g kg -1 DM and reduced Na concentration to 3.5 g kg -1 DM. Sodium fertiliser, therefore, only increased the acceptability of herbage to cattle when herbage Na concentrations were initially low (less than 5 g kg -1 DM) and were increased substantially by the application of the fertiliser.

Influenza virus contains two highly variable envelope glycoproteins, hemagglutinin (HA) and neuraminidase (NA). The structure and properties of HA, which is responsible for binding the virus to the cell that is being infected, change significantly when the virus is transmitted from avian or swine species to humans. Here we focus first on the simpler problem of the much smaller human individual evolutionary amino acid mutational changes in NA, which cleaves sialic acid groups and is required for influenza virus replication. Our thermodynamic panorama shows that very small amino acid changes can be monitored very accurately across many historic (1945–2011) Uniprot and NCBI strains using hydropathicity scales to quantify the roughness of water film packages. Quantitative sequential analysis is most effective with the fractal differential hydropathicity scale based on protein self-organized criticality (SOC). Our analysis shows that large-scale vaccination programs have been responsible for a very large convergent reduction in common influenza severity in the last century. Hydropathic analysis is capable of interpreting and even predicting trends of functional changes in mutation prolific viruses directly from amino acid sequences alone. An engineered strain of NA1 is described which could well be significantly less virulent than current circulating strains.

Recent experimental data on the conductivity σ + ( T ), T → 0, on the metallic side of the metal–insulator transition in ideally random (neutron transmutation-doped) 70 Ge:Ga have shown that σ + (0) ∝ ( N − N c ) μ with μ = ½, confirming earlier ultra-low-temperature results for Si:P. This value is inconsistent with theoretical predictions based on diffusive classical scaling models, but it can be understood by a quantum-directed percolative filamentary amplitude model in which electronic basis states exist which have a well-defined momentum parallel but not normal to the applied electric field. The model, which is based on a new kind of broken symmetry, also explains the anomalous sign reversal of the derivative of the temperature dependence in the critical regime.

A new theory of glassy relaxation has recently identified two intrinsic stretched exponential relaxation channels associated with charge and density fluctuations characterized by two magic stretching fractions, and . The theory is revised here to describe structural relaxation in the presence of defects such as kinks in polymers. The revised theory explains recent NMR multiple-spin-echo experiments which exhibit two corresponding relaxation modes (`slow' and `fast'). A remarkable byproduct of the theory is an explanation of the origin of the Vogel - Fulcher `singularity' in the viscosity of fragile glass formers near the glass transition as the result of two-stage structural arrest.

A field experiment was conducted to examine the effects of applying sodium fertiliser on the chemical composition of perennial ryegrass and white clover leaves of different physiological ages. When no sodium fertiliser was applied the cation concentrations increased up to the point of senescence in grass leaves and then declined in the dead leaves. Sodium fertiliser increased the contents of sodium from 6 to 9 g kg -1 DM and magnesium from 2.2 to 3.4 g -1 kg DM in young grass leaves, but both declined to a low level in dead leaves. It decreased the content of potassium in young grass leaves and calcium in older leaves. Clover leaves were less responsive to sodium fertiliser than grass, but older clover leaves had an increased sodium content and reduced calcium content when sodium was applied. All clover leaves responded to sodium by increasing chloride and reducing magnesium contents. The nutritional value of grass, but not clover, was reduced by sodium fertiliser, with an increase in fibre content and a decrease in crude protein content and DM digestibility. This probably occurred because of the high content of sodium in the herbage without sodium fertiliser. It is concluded that young grass leaves tend to be more responsive to sodium fertiliser than old leaves, and that clover is less responsive than grass.

Poly(vinylidene fluoride) films in ethyl acetate vapor were studied at 30°C for vapor pressures of p = 0, 12, 30, 40, 66, 85 torr and elongations e = 4.5%, 7%, 9.5%, 19%, 29%, and 44%. A cyclic experiment was also performed at e = 7% and p = 40 torr for three sorption/desorption cycles. Assuming, as a first approximation, that the stress relaxation of the “dry” and “wet” polymers is proportional to the elastic strain, eel, empirical calculations were performed and compared to experimental results. In general, the presence of a vapor or gas in a polymer matrix enhances the stress relaxation by softening or plasticizing the polymer and transforming a portion of the elastic strain, eel, into the plastic strain, epl. As the transformation continues, the sorption and stress of the wetted elongated sample change simultaneously with time until an optical “overshoot” and a mechanical or stress “undershoot” is observed. This result seems to be the consequence of the differential change of the stress of the “dry” and “wetted” samples with sorption time, τ = t − to(t = time; to = initial sorption time), which depends on the differential time dependencies of the transformations of the elastic and plastic strains.