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Background Methods Results Discussion Many youth experiencing first-episode psychosis face more academic and vocational challenges than their peers. Yet few studies have explored the perspectives of youth who are not in education, employment or training (NEET) following psychosis and contrasted these with those of their counterparts engaged in education and/or employment. To address this gap, this study explored personal journeys of (re-)engaging in education and employment after psychosis.Using a descriptive qualitative design, grounded in self-determination theory, in-depth interviews were conducted with individuals receiving services at an early intervention program for psychosis. Eight youth who were NEET and six who were working/in education participated.The analysis produced three themes that were salient to both youth with psychosis who were NEET and those in work/school: relatedness or the importance of belonging and being cared for; perceived competence; and a desire for a sense of autonomy. The themes, aligned with the self-determination theory, showed youths negotiating their decision to (re-)engage in education and employment.Engaging in education and employment seems part of a larger process that draws on significant past experiences and the envisioned future self. Efforts targeting vocational functioning are best situated in understandings of identity, recovery, and psychological needs. [ABSTRACT FROM AUTHOR]

Background -- In southern Australia up to 2 million hectares of land in the high rainfall and mixed farming zones is affected by dryland salinity. Despite our best efforts to counter this problem through the strategic management of recharge areas, over the next 20 years more land will become saline, leaving some individual farmers with up to 30% of their property affected. Much of this land may never be returned to its former condition. However, it has been suggested that approximately 50% of salt affected land is suitable for improvement by planting halophyte-based (salt tolerant) pastures. This has significant implications for animal production, as only the grazing industry has the existing infrastructure and markets to make productive use of such land on this scale. Accordingly, a key aim of the CRC is to understand the consequences, opportunities and risks associated with feeding ruminants high salt diets, as well as other secondary compounds known to accumulate in halophytic plants. Objectives -- To determine the physiological and functional implications of feeding high salt diets to grazing ruminants, so that risks and benefits can be identified, and production systems optimized, to make the best use of saline land. Design -- A program of research has been designed to investigate numerous aspects of salt tolerance in ruminants, from the level of the farm production system, through studies on the individual animal, down to the molecular level of cellular responses. Comparative studies using cattle, and various breeds of sheep selected for meat or wool production, will help to identify the existing species and breeds that are best suited to grazing salty pastures. Physiological responses of sheep to high salt diets are being measured, in terms of diet selection, feed intake, digestibility, growth rate, feed conversion efficiency, and water requirement. The effect of a salt load on fetal development has been investigated in pregnant sheep and their lambs. Endocrine markers of the response to NaCl are being sought, with a view to developing rapid screening, selection and toxicity tests. The way in which salt affects rumen microorganisms is being investigated at the molecular level, and physiological responses are being measured in both plants and sheep after grazing saltbush, to identify and characterize the effects of secondary compounds in a halophyte diet. Outcomes -- Dietary NaCl decreases feed intake and digestibility in ruminants in a concentration-dependant manner, and beyond a concentration of approximately 12% NaCl, growth in sheep is depressed significantly. Nevertheless, sheep will select a high energy/high protein feed that is also high in salt, in preference to a feed that is low in salt, protein and energy, and will combine high and low salt feeds to improve the overall quality of their diet. At low levels of NaCl (up to 8% dry matter) cattle appear to tolerate salty diets better than expected, and do not show the same depression in feed intake observed in sheep. Furthermore, at high salt concentrations (20% dry matter), feed efficiency is improved markedly in cattle (and to a lesser extent in sheep), such that body weight is maintained for up to 6 wk, despite a 50% reduction in organic matter intake. When a salt load of 15% NaCl was administered to ewes throughout pregnancy, no detrimental effects were observed on blood pressure, lambing rate, or lactation, with some evidence that the pattern of water consuption and urine output in their lambs is altered following an acute salt challenge. Both insulin and leptin concentrations are altered by feeding salty diets, but further work is needed to isolate the direct effects of NaCl from those mediated by associated changes in feed intake. Only a small proportion of the rumen microbial population is able to tolerate high concentrations of NaCl added to rumen fluid in vitro.… [ABSTRACT FROM AUTHOR]

Background -- Tryptophan (Trp) is an essential amino acid that is a precursor of serotonin, a neurotransmitter implicated in sedation, inhibition of aggression, fear and stress in various animal species and humans. Preparations containing Trp are marketed worldwide as calmative agents to treat excitable horses, but there is no evidence of their efficacy. Coupled with this, it has been shown that high oral doses can be toxic. No work has been done to establish that commercial pastes actually increase Trp concentrations in the blood of horses, or how long this elevation lasts. Objectives -- To determine if a commercial Trp oral paste increases plasma Trp concentrations and to establish whether the pharmacokinetics of Trp are altered by different feeding regimens. Design -- Eleven mature geldings (BW 507 ± 12.9 kg) were fed a meal of 2.7 kg lucerne hay at 0900 h each day, supplemented in the afternoon with sufficient hay to meet maintenance energy requirements. At 0900 h the horses were also given either 3 doses of a commercial Trp oral paste (total 6.3 g L-Trp) or an equivalent volume of water in a crossover design. Blood samples were collected every 30 min for 6 h and analysed for total Trp using gas chromatography. The study was repeated after 3 weeks using the same horses fed a morning meal of 1.5 kg oats. Outcomes -- Baseline Trp concentrations measured 2 h after feeding were 71.8 ± 3.7µM and 36.7 ± 3.4 µM for horses fed lucerne hay or oats, respectively (P < 0.001). Peak Trp concentration in response to Trp paste was also higher in horses fed hay (167.6 ± 8.0 µM at 1130 h) versus oats (149.4 ± 13.7 µM at 1030 h; P <0.001), as was the area under a plot of Typ concentration versus time (227.8 ± 8.7 µM.h versus 179.1 ± 14.9 µM.h; P<0.01). Tryptophan concentrations returned to baseline after 6 hours regardless of the ration fed. Conclusion -- No adverse signs were seen in this study although the effect of such doses fed over a more prolonged period is unknown. Tryptophan paste fed at this level does increase plasma Trp concentrations in horses. The amount and duration of this elevation is dependent on the type of diet fed. Further work is needed to determine if the Trp paste fed at lower doses has an effect and whether in fact an increase in Trp concentrations has any effect on equine behaviour. [ABSTRACT FROM AUTHOR]

The objective of this study was to characterize porcine ß1- and ß2-adrenergic receptors (ß1-AR and ß2-AR) in heart, skeletal muscle, and adipose tissue by measuring the binding of a radioligand to cell membrane fragments. In skeletal muscle (LM), [3H]CGP12 177 labeled a homogeneous population of ß2- AR as evidenced by the rank order of affinity of catecholamines [(-)isoproterenol> (-)epinephrine > (-)norepinephrine], a high affinity of the binding site for the ß2- AR-agonist clenbuterol (equilibrium dissociation constant, Kd = 16 nM), and a low affinity of the binding site for the ß1-AR-antagonist CGP2O712A (Kd =21 μM). The affinity of ICI118551, a ligand selective for ß2-AR in other species, was uncharacteristically low in porcine LM (Kd3 = 441 nM), but was consistent with a value reported for the cloned porcine ß2-AR. In heart ventricle, ligand binding revealed a predominant population of ß-AR, judged by the rank order of affinity of catecholamines [(-)isoproterenol > (-)epinephrine > (-)norepinephrine] and high-affinity binding to CGP2O712A (K d = 40 nM). The K dd for 1C1118551 (731 nM) was close to that observed at ß2-AR in LM, confirming that 1C1118551 is not subtype-selective in the pig. Displacement studies using (-)propranolol, clenbuterol, and (-)isoproterenol revealed a second high-affinity binding site in the heart that was not a ,ß2-AR and could not be eliminated by guanosine 5'-triphosphate or guanylyli- midodiphosphate. In adipose tissue, an equal number of ß1- and ß2-AR was identified through the binding of clenbuterol and CGP2O712A, whereas 1C1118551 could not discriminate between these sites. In further experiments, we used 10 μM CGP20712A to eliminate ß1-AR binding and allow accurate Kd values to be determined at ß2-AR for nonselective ligands. Under these conditions, another binding site was observed that had a high affinity for (-)propranolol (Kd = 20 pM), which is inconsistent withß3 or ß4-AR binding reported else- where. Our results indicate that porcine adipose tissue contains ß1-AR, ß2-AR, and an atypical binding site in the proportions 50, 34, and 16%, respectively, of the total binding sites labeled by [3H]CGP12177. [ABSTRACT FROM AUTHOR]

The effects of sewage sludge contaminated with heavy metals on the symbiotic effectiveness of R. trifolii, white clover N2 fixation and N mineralisation were investigated in surface (0--10 cm) soil from a 10 year-old field experiment at Glenfield, NSW. The soil had been amended with nil, low (40 dry t ha-1) or high (120 dry t ha-1) rates of sludge, applied annually for 5 consecutive years to an unlimed (pH 4.6) and limed (pH 5.2) red podsolic soil. The total heavy metal content of the soil collected from the site5 years after the last sludge application ranged (mg kg- 1 soil) 114--122 (nil sludge), 286--295 (low sludge) and 532-- 583 (high sludge). Air-dried soil was sieved (< 2 mm), then placed in pots which were sown to white clover and ryegrass, or to ryegrass only. The amount and proportion of clover N derived from air after 7 weeks growth in a glasshouse were determined using 15N isotope dilution; and the intrinsic symbiotic effectiveness (ISE) of R. trifoliiisolated from the clover nodules was estimated from the N yield of clover seedlings grown on N-free seedling agar inoculated with the isolates. Treatment effects on N mineralisation were determined from theconcentrations of inorganic N released on soil incubation with or without incorporated lucerne. Amending soil with sludge did not reduce the ISE of R. trifolii in either unlimed or limed soil, the between-isolate variance in ISE, nor the proportion of clover N derived from air, as compared to unamended soil. The amount of N fixed by clover was increased in the sludged soils. The concentrations of inorganic N in the N mineralisaion study were greater in the sludge amended soils and with incorporation of lucerne; and the differences in inorganic Nbetween plus and minus lucerne incorporation were similar in both the sludged and unamended soils. The sludge rates and associated heavy metal loads historically imposed on this soil have not proven detrimental [ABSTRACT FROM AUTHOR]