Osmoregulative capacity in birdseed millet under conditions of water stress. I. Variation in Setaria italica and Panicum miliaceum

Experiments involving 14 accessions of Panicum miliaceum L. (Proso millet) and 11 accessions of Setaria italica L. (Foxtail millet) have demonstrated variability in the degree of osmoregulative capacity among these accessions. Birdseed millet is generally claimed to be sensitive to drought stress, apparently because of a shallow root system. Accessions with high osmoregulative capacity demonstrate at least some drought tolerance. Osmoregulative capacity was measured on flag leaves of headed millet plants in pots undergoing water stress in a controlled environment chamber. Osmoregulative capacity was determined from the relationship between osmotic potential and leaf water potential; and the logarithmic relationship between osmotic potential and relative water content. The group of accessions of S. italica showed an overall level of osmoregulative capacity which was greater than that observed for the group of P. miliaceum accessions. Four accessions of S. italica (108042, 108463, 108541 and 108564) and one accession of P. miliaceum (108104) demonstrated high osmoregulative capacity. Differences of 1.05 MPa or more between observed and estimated osmotic potential were found at relative water contents of 80 % among these accessions. The extent of osmoregulative capacity was associated with osmotic potential at full turgor and the rate of decline in osmotic potential as leaf water potentail declined.

Evaluation of various pre-treatments for the dehydration of banana and selection of suitable drying models

The thin-layer drying behaviour of bananas in a beat pump dehumidifier dryer was examined. Four pre-treatments (blanching, chilling, freezing and combined blanching and freezing) were applied to the bananas, which were dried at 50 degreesC with an air velocity of 3.1 m s(-1) and with the relative humidity of the inlet air of 10-35%. Three drying models, the simple model, the two-term exponential model and the Page model were examined. All models were evaluated using three statistical measures, correlation coefficient, root means square error, and mean absolute percent error. Moisture diffusivity was calculated based on the diffusion equation for an infinite cylindrical shape using the slope method. The rate of drying was higher for the pre-treatments involving freezing. The sample which was blanched only did not show any improvement in drying rate. In fact, a longer drying time resulted due to water absorption during blanching. There was no change in the rate for the chilled sample compared with the control. While all models closely fitted the drying data, the simple model showed greatest deviation from the experimental results. The two-term exponential model was found to be the best model for describing the drying curves of bananas because its parameters represent better the physical characteristics of the drying process. Moisture diffusivities of bananas were in the range 4.3-13.2 x 10(-10) m(2)s(-1). (C) 2002 Published by Elsevier Science Ltd.

Application of the maximum entropy method to the (2 + 1)D four-fermion model

We investigate spectral functions extracted using the maximum entropy method from correlators measured in lattice simulations of the (2+1)-dimensional four-fermion model. This model is particularly interesting because it has both a chirally broken phase with a rich spectrum of mesonic bound states and a symmetric phase where there are only resonances. In the broken phase we study the elementary fermion, pion, sigma, and massive pseudoscalar meson; our results confirm the Goldstone nature of the π and permit an estimate of the meson binding energy. We have, however, seen no signal of σ→ππ decay as the chiral limit is approached. In the symmetric phase we observe a resonance of nonzero width in qualitative agreement with analytic expectations; in addition the ultraviolet behavior of the spectral functions is consistent with the large nonperturbative anomalous dimension for fermion composite operators expected in this model.

Cholesterol-lowering therapy with pravastatin in patients with average cholesterol levels and established ischaemic heart disease: is it cost-effective?

Objective: To measure the cost-effectiveness of cholesterol-lowering therapy with pravastatin in patients with established ischaemic heart disease and average baseline cholesterol levels. Design: Prospective economic evaluation within a double-blind randomised trial (Long-Term Intervention with Pravastatin in Ischaemic Disease [LIPID]), in which patients with a history of unstable angina or previous myocardial infarction were randomised to receive 40 mg of pravastatin daily or matching placebo. Patients and setting: 9014 patients aged 35-75 years from 85 centres in Australia and New Zealand, recruited from June 1990 to December 1992. Main outcome measures: Cost per death averted, cost per life-year gained, and cost per quality-adjusted life-year gained, calculated from measures of hospitalisations, medication use, outpatient visits, and quality of life. Results: The LIPID trial showed a 22% relative reduction in all-cause mortality (P < 0.001). Over a mean follow-up of 6 years, hospital admissions for coronary heart disease and coronary revascularisation were reduced by about 20%. Over this period, pravastatin cost $A4913 per patient, but reduced total hospitalisation costs by $A1385 per patient and other long-term medication costs by $A360 per patient. In a subsample of patients, average quality of life was 0.98 (where 0 = dead and 1 = normal good health); the treatment groups were not significantly different. The absolute reduction in all-cause mortality was 3.0% (95% CI, 1.6%-4.4%), and the incremental cost was $3246 per patient, resulting in a cost per life saved of $107730 (95% Cl, $68626-$209881) within the study period. Extrapolating long-term survival from the placebo group, the undiscounted cost per life-year saved was $7695 (and $10 938 with costs and life-years discounted at an annual rate of 5%). Conclusions: Pravastatin therapy for patients with a history of myocardial infarction or unstable angina and average cholesterol levels reduces all-cause mortality and appears cost effective compared with accepted treatments in high-income countries.

Effect of Rosiglitazone on Insulin Sensitivity and Body Composition in Type 2 Diabetic Patients

Objective: To investigate the effects of rosiglitazone (RSG) on insulin sensitivity and regional adiposity (including intrahepatic fat) in patients with type 2 diabetes. Research Methods and Procedures: We examined the effect of RSG (8 mg/day, 2 divided doses) compared with placebo on insulin sensitivity and body composition in 33 type 2 diabetic patients. Measurements of insulin sensitivity (euglycemic hyperinsulinemic clamp), body fat (abdominal magnetic resonance imaging and DXA), and liver fat (magnetic resonance spectroscopy) were taken at baseline and repeated after 16 weeks of treatment. Results: There was a significant improvement in glycemic control (glycosylated hemoglobin -0.7 +/- 0.7%, p less than or equal to 0.05) and an 86% increase in insulin sensitivity in the RSG group (glucose-disposal rate change from baseline: 17.5 +/- 14.5 mumol glucose/min/kg free fat mass, P < 0.05), but no significant change in the placebo group compared with baseline. Total body weight and fat mass increased (p &LE; 0.05) with RSG (2.1 +/- 2.0 kg and 1.4 +/- 1.6 kg, respectively) with 95% of the increase in adiposity occurring in nonabdominal regions. In the abdominal region, RSG increased subcutaneous fat area by 8% (25.0 +/- 28.7 cm(2), p = 0.02), did not alter intra-abdominal fat area, and reduced intrahepatic fat levels by 45% (-6.7 +/- 9.7%, concentration relative to water). Discussion: Our data indicate that RSG greatly improves insulin sensitivity in patients with type 2 diabetes and is associated with an increase in adiposity in subcutaneous but not visceral body regions.

The Relative Frequency of the Synthetic End Composite Futures in the Newspaper Quest-France and some Observations on Distribution

Figures on the relative frequency of synthetic and composite future forms in Ouest-France are presented and compared with those of earlier studies on the passé simple and passé composé. The synthetic future is found to be dominant. Possible formal explanations for distribution are found to be inconclusive. Distribution across different text-types is found to be more promising, since contrastive functions of the two forms can be identified in texts where they co-occur. The composite future typically reports new proposals or plans as current news, while the synthetic future outlines details that will be realised at the time of implementation. Both functions are important in dailies, but current news is more often expressed in the present tense at the expense of the composite future.

Routine ultrasound screening in diabetic pregnancies

Objectives To assess the detection rate of congenital fetal malformations and specific problems related to routine ultrasound screening in women with pre-existing diabetes. Methods A retrospective study was carried out to assess the performance of routine ultrasound screening in women with pre-existing diabetes (Types 1 and 2) within a tertiary institution. The incidence, type and risk factors for congenital fetal malformations were determined. The detection rate of fetal anomalies for diabetic women was compared with that for the low-risk population. Factors affecting these detection rates were evaluated. Results During the study period, 12 169 low-risk pregnant women and 130 women with pre-existing diabetes had routine ultrasound screening performed within the institution. A total of 10 major anomalies (7.7%) and three minor anomalies (2.3%) were present in the fetuses of the diabetic women. Central nervous system and cardiovascular system anomalies accounted for 60% of the major anomalies. Peri-conceptional hemoglobin A 1 c of more than 9% was associated with a high prevalence of major anomalies (14311000). Women who had fetuses with major anomalies bad a significantly higher incidence of obesity (78% vs. 37%; P < 0.05). Ultrasound examination of these diabetic pregnancies showed high incidences of suboptimal image quality (37%), incomplete examinations, and repeat examinations (17%). Compared to the 'low-risk' non-diabetic population from the same institution, the relative risk for a major congenital anomaly among the diabetic women was 5.9-fold higher (95% confidence interval, 2.9-11.9). The detection rate for major fetal anomalies was significantly lower for diabetic women (30% vs. 73%; P < 0.01), and the mean body mass index for the diabetic group was significantly higher (29 vs. 23 kg/m(2); P < 0.001). Conclusion The incidence of congenital anomalies is higher in diabetic pregnancies. Unfortunately, the detection rate for fetal anomalies by antenatal ultrasound scan was significantly, worse than that for the low-risk population. This is likely to be related to the maternal body habitus and unsatisfactory examinations. Methods to overcome these difficulties are discussed.

Mathematical modelling of schistosomiasis japonica: comparison of control strategies in the People's Republic of China

We present the first mathematical model on the transmission dynamics of Schistosoma japonicum. The work extends Barbour's classic model of schistosome transmission. It allows for the mammalian host heterogeneity characteristic of the S. japonicum life cycle, and solves the problem of under-specification of Barbour's model by the use of Chinese data we are collecting on human-bovine transmission in the Poyang Lake area of Jiangxi Province in China. The model predicts that in the lake/marshland areas of the Yangtze River basin: (1) once-early mass chemotherapy of humans is little better than twice-yearly mass chemotherapy in reducing human prevalence. Depending on the heterogeneity of prevalence within the population, targeted treatment of high prevalence groups, with lower overall coverage, can be more effective than mass treatment with higher overall coverage. Treatment confers a short term benefit only, with prevalence rising to endemic levels once chemotherapy programs are stopped (2) depending on the relative contributions of bovines and humans, bovine treatment can benefit humans almost as much as human treatment. Like human treatment, bovine treatment confers a short-term benefit. A combination of human and bovine treatment will dramatically reduce human prevalence and maintains the reduction for a longer period of time than treatment of a single host, although human prevalence rises once treatment ceases; (3) assuming 75% coverage of bovines, a bovine vaccine which acts on worm fecundity must have about 75% efficacy to reduce the reproduction rate below one and ensure mid-term reduction and long-term elimination of the parasite. Such a vaccination program should be accompanied by an initial period of human treatment to instigate a short-term reduction in prevalence, following which the reduction is enhanced by vaccine effects; (4) if the bovine vaccine is only 45% efficacious (the level of current prototype vaccines) it will lower the endemic prevalence, but will not result in elimination. If it is accompanied by an initial period of human treatment and by a 45% improvement in human sanitation or a 30% reduction in contaminated water contact by humans, elimination is then possible. (C) 2002 Elsevier Science B.V. All rights reserved.

Risk factors for non-haemorrhagic stroke in patients with coronary heart disease and the effect of lipid-modifying therapy with pravastatin

Objective To determine the relative importance of recognised risk factors for non-haemorrhagic stroke, including serum cholesterol and the effect of cholesterol-lowering therapy, on the occurrence of non-haemorrhagic stroke in patients enrolled in the LIPID (Long-term Intervention with Pravastatin in Ischaemic Disease) study. Design The LIPID study was a placebo-controlled, double-blind trial of the efficacy on coronary heart disease mortality of pravastatin therapy over 6 years in 9014 patients with previous acute coronary syndromes and baseline total cholesterol of 4-7 mmol/l. Following identification of patients who had suffered non-haemorrhagic stroke, a pre-specified secondary end point, multivariate Cox regression was used to determine risk in the total population. Time-to-event analysis was used to determine the effect of pravastatin therapy on the rate of non-haemorrhagic stroke. Results There were 388 non-haemorrhagic strokes in 350 patients. Factors conferring risk of future non-haemorrhagic stroke were age, atrial fibrillation, prior stroke, diabetes, hypertension, systolic blood pressure, cigarette smoking, body mass index, male sex and creatinine clearance. Baseline lipids did not predict non-haemorrhagic stroke. Treatment with pravastatin reduced non-haemorrhagic stroke by 23% (P= 0.016) when considered alone, and 21% (P= 0.024) after adjustment for other risk factors. Conclusions The study confirmed the variety of risk factors for non-haemorrhagic stroke. From the risk predictors, a simple prognostic index was created for nonhaemorrhagic stroke to identify a group of patients at high risk. Treatment with pravastatin resulted in significant additional benefit after allowance for risk factors. (C) 2002 Lippincott Williams Wilkins.

Simulation of the influence of rate- and state-dependent friction on the macroscopic behavior of complex fault zones with the lattice solid model

In order to understand the earthquake nucleation process, we need to understand the effective frictional behavior of faults with complex geometry and fault gouge zones. One important aspect of this is the interaction between the friction law governing the behavior of the fault on the microscopic level and the resulting macroscopic behavior of the fault zone. Numerical simulations offer a possibility to investigate the behavior of faults on many different scales and thus provide a means to gain insight into fault zone dynamics on scales which are not accessible to laboratory experiments. Numerical experiments have been performed to investigate the influence of the geometric configuration of faults with a rate- and state-dependent friction at the particle contacts on the effective frictional behavior of these faults. The numerical experiments are designed to be similar to laboratory experiments by DIETERICH and KILGORE (1994) in which a slide-hold-slide cycle was performed between two blocks of material and the resulting peak friction was plotted vs. holding time. Simulations with a flat fault without a fault gouge have been performed to verify the implementation. These have shown close agreement with comparable laboratory experiments. The simulations performed with a fault containing fault gouge have demonstrated a strong dependence of the critical slip distance D-c on the roughness of the fault surfaces and are in qualitative agreement with laboratory experiments.

Distributional profiles of homologous open reading frames among bacterial phyla: implications for vertical and lateral transmission

If open reading frames (ORFs) have been transmitted primarily by vertical descent, the distributional profile of orthologues of each ORF should be congruent with the organismal tree or a subtree thereof. Distributional patterns not reconciled parsimoniously with tree-like descent and loss are prima facie evidence of lateral gene transfer. Herein, a rigorous criterion for recognizing ORF distributions is described and implemented; it does not require the inference of phylogenetic trees, nor does it assume any specific tree. Because lineage-specific differences in rates of sequence change can also generate unexpected distributional patterns, rate artefacts, were controlled for by requiring pairwise matches between ORFs to exceed a rigorous inclusion threshold, but absence of a match was assessed against a more-permissive exclusion threshold. Applying this dual-threshold criterion to cross-domain and cross-phylum distributional patterns for ORFs in 23 bacterial genomes, a relative abundance of ORFs was observed that find a match in exactly seven other bacterial phyla; 94-99% of these ORFs also find matches among the Archaea and/or Eukarya. In the larger (and some smaller) bacterial genomes, ORFs that find matches in exactly one other bacterial phylum are also relatively abundant, but fewer of these have non-bacterial homologues; most of their matches within the Bacteria are to the Proteobacteria and/or Firmicutes, which cannot be sister lineages to all bacteria. ORFs that are neither distributed universally among the Bacteria, nor necessarily shared with topologically adjacent lineages, are preferentially enriched in large bacterial genomes.

Stressful animal housing conditions and their potential effect on sympathetic neurotransmission in mice

Although the sympathetic nervous system (SNS) plays a major role in mediating the peripheral stress response, due consideration is not usually given to the effects of prolonged stress on the SNS. The present study examined changes in neurotransmission in the SNS after exposure of mice (BALB/c) to stressful housing conditions. Focal extracellular recording of excitatory junction currents (EJCs) was used as a relative measure of neurotransmitter release from different regions of large surface areas of the mouse vas deferens. Mice were either group housed (control), isolation housed (social deprivation), group housed in a room containing rats (rat odor stress), or isolation housed in a room containing rats (concurrent stress). Social deprivation and concurrent stressors induced an increase of 30 and 335% in EJC amplitude, respectively. The success rate of recording EJCs from sets of varicosities in the concurrent stressor group was greater compared with all other groups. The present study has shown that some common animal housing conditions act as stressors and induce significant changes in sympathetic neurotransmission.

Physiological profiles of restricted endemic plants and their widespread congenors in the North Queensland wet tropics, Australia

Little is known about causes of endemic rarity in plants. This study pioneered an approach that determined environmental variables in the rainforest habitat and generated physiological profiles for light, water, and nutrient relations for three endemically restricted versus widespread congeneric species' pairs. We found no overall consistent differences in the physiological variables between the group of restricted species and the group of widespread species, and congeneric species pairs were therefore examined individually. Availability of soil nutrients did not differ between restricted-widespread species sites suggesting that species grow under comparable nutrient conditions. Under ambient and manipulated higher light conditions, widespread Gardenia ovularis had a greater photosynthetic activity than restricted Gardenia actinocarpa suggesting that the two species differ in their photosynthetic abilities. Differences between Xanthostemon species included lower photosynthetic activity, higher transpiration rate, and a higher foliar manganese concentration in restricted Xanthostemon formosus compared to widespread Xanthostemon chrysanthus. It is suggested that X. formosus is restricted by its high water use to its current rainforest creek edge habitat, while X. chrysanthus grows in a range of environments, although naturally found in riparian rainforest. Restricted Archidendron kanisii had higher electron transport rates, greater dissipative capacity for removal of excess light, and more efficient investment of nitrogen into photosynthetic components, than its widespread relative Archidendron whitei. These observations and previous research suggest that restricted Archidendron kanisii is in the process of expanding its range. Physiological profiles suggest a different cause of rarity for each species. This has implications for the conservation strategies required for each species. (C) 2002 Elsevier Science Ltd. All rights reserved.

Exchange rate sensitivity of Australian international equity funds

This paper analyses the exchange rate exposure displayed by a sample of Australian international equity trusts (IET). Exchange rate exposure is also examined in the context of differing economic climates with particular emphasis on the Asian crisis in mid-1997. It is found that there is evidence of exchange rate exposure particularly in the context of a multiple exchange rate model. Exposure varies substantially between three alternative time periods with different exposure apparent subsequent to the Asian crisis than prior to this event.