The effect of incentive reforms upon productivity: Evidence from the Vietnamese rice industry

In this study we use region-level panel data on rice production in Vietnam to investigate total factor productivity (TFP) growth in the period since reunification in 1975. Two significant reforms were introduced during this period, one in 1981 allowing farmers to keep part of their produce, and another in 1987 providing improved land tenure. We measure TFP growth using two modified forms of the standard Malmquist data envelopment analysis (DEA) method, which we have named the Three-year-window (TYW) and the Full Cumulative (FC) methods. We have developed these methods to deal with degrees of freedom limitations. Our empirical results indicate strong average TFP growth of between 3.3 and 3.5 per cent per annum, with the fastest growth observed in the period following the first reform. Our results support the assertion that incentive related issues have played a large role in the decline and subsequent resurgence of Vietnamese agriculture.

A survey of dental and oral trauma in south-east Queensland during 1998

Background: This project investigated the aetiology of dental and oral trauma in a population in southeast Queensland. The literature shows there is a lack of dental trauma studies which are representative of the general Australian population. Method: Twelve suburbs in the south-east district of Queensland were randomly selected according to population density in these suburbs for each 25th percentile. All dental clinics in these suburbs were eligible to participate. Patients presenting with dental and oral trauma were eligible to participate. Results: A total of 197 patients presented with dental/oral trauma over a 12 month period. The age of patients ranged from 1-64 years whilst the most frequently presenting age group was 6-10 years. There was a total of 363 injured teeth with an average of 1.8 injured teeth per patient. Males significantly outnumbered females in the incidence of trauma. Conclusions: The highest frequency of trauma occurred in the 6-10 year age group. Most injuries in this group occurred while playing or riding bicycles. In the next most prevalent trauma group, 16-20 years, trauma occurred as a result of fighting and playing sport. Overall, males significantly outnumbered females by approximately 1.8:1.0. The majority of injuries in the deciduous dentition were to periodontal tissues. In the secondary dentition most injuries were to hard dental tissue and pulp.

Tree use, diet and home range of the koala (Phascolarctos cinereus) at Blair Athol, central Queensland

Free-ranging koalas (Phascolarctos cinereus) were monitored by means of radio-relocation in the area of Blair Athol Coal Mine and surrounding properties. Daytime tree use, home range and diet of these koalas was determined in spring and autumn, as was the leaf moisture composition of potential fodder species. Koalas used on average 93 (male koalas) and 56 (female koalas) trees during the period of observation, occupying home ranges of 135 and 101 ha respectively. Mean sightings per tree were 1.19 for both males and females and home-range sizes were not significantly different between sexes or seasons. Koalas were observed returning to previously used daytime roosting trees infrequently (

A simple formula for the average gate fidelity of a quantum dynamical operation

This Letter presents a simple formula for the average fidelity between a unitary quantum gate and a general quantum operation on a qudit, generalizing the formula for qubits found by Bowdrey et al. [Phys. Lett. A 294 (2002) 258]. This formula may be useful for experimental determination of average gate fidelity. We also give a simplified proof of a formula due to Horodecki et al. [Phys. Rev. A 60 (1999) 1888], connecting average gate fidelity to entanglement fidelity. (C) 2002 Elsevier Science B.V. All rights reserved.

Productivity growth in pre-1990 Mongolian agriculture: Spiralling disaster or emerging success?

The reasons for the spectacular collapse of so many centrally-planned economies are a source of ongoing debate. In this paper, we use detailed farm-level data to measure total factor productivity (TFP) changes in Mongolian grain and potato farming during the 14-year period immediately preceding the 1990 economic reforms. We measure TFP growth using stochastic frontier analysis (SFA) and data envelopment analysis (DEA) methods. Our results indicate quite poor overall performance, with an average annual TFP change of - 1.7% in grain and 0.8% in potatoes, over the 14-year period. However, the pattern of TFP growth changed substantially during this period, with TFP growth exceeding 7% per year in the latter half of this period. This suggests that the new policies of improved education, greater management autonomy, and improved incentives, which were introduced in final two planning periods in the 1980s, were beginning to have a significant influence upon the performance of Mongolian crop farming. Crown Copyright (C) 2002 Published by Elsevier Science B.V. All rights reserved.

Assault-related admissions to hospital in Central Australia

Objective: To determine the number of assault-related admissions to hospital in the Central Australia region of the Northern Territory over a six-year period. Design and setting: Retrospective analysis of all patients admitted to Alice Springs Hospital (ASH) and Tennant Creek Hospital (TCH) from July 1995 to June 2001, where the primary cause of injury was assault. Main outcome measures: Frequency of assault-related admission to hospital; demographic characteristics of the victims. Results: in the six years, there were 2449 assault-related admissions to ASH and 545 to TCH. Adults aged 25-34 years were most frequently hospitalised for assault, in a proportion greater than their proportion in the NT population, Females represented 59.7% of people admitted to ASH and 54.7% to TCH, greater than their proportion in the NT population. Aboriginals comprised 95.2% of ASH and 89.0% of TCH admissions, and were admitted in a significantly greater proportion than their proportion in the NT population (P < 0.001). The age-adjusted hospital admission rate resulting from assault has increased (P = 0.002) at an average rate of 1.6 (SE, 0.2) per 10 000 people per year. The proportion of assault-related admissions associated with alcohol has also increased significantly (P < 0.001). Conclusion: The frequency of assault-related admissions to hospital, especially among the Aboriginal population, suggests that this major public health issue is escalating.

Airborne pollen of Brisbane, Australia: a five-year record, 1994-1999

The seasonal incidence of pollen in the atmosphere of Brisbane has been established from a near continuous. volumetric trapping program over the five-year period, July 1994-June 1999. Grass pollen accounts for 71.6% of the average annual pollen load with highest densities (up to 150 grains/m(3)) recorded in summer and autumn. Significant contributions were also made by taxa of the Cupressaceae (8.7%) and Urticaceae (1.8%) during spring and of the Pinaceae (4.5%) during winter. Pollen seasons of the Casuarinaceae (6.5%) and Myrtaceae (3.2%) are more extended, the former peaking in late winter and the latter in late spring. The onset and duration of the Poaceae and Urticaceae seasons varied from year to year, being later when precipitation levels were low in the late spring-early summer months. Total pollen numbers and grass pollen densities are substantially less than those recorded from southern Australia. Nevertheless, respiratory disease in Brisbane affects up to 10% of the population, and airborne pollen of Poaceae, Urticaceae, Cupressaceae, Pinaceae, and Myrtaceae have been implicated in the release of allergens.

Acquisition and loss of Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans and Prevotella intermedia over a 5-year period: effect of a triclosan/copolymer dentifrice

Objectives: The present study describes the natural history of Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans and Prevotella intermedia over a 5-year period and the effect of a triclosan/copolymer dentifrice on these organisms in a normal adult population. Material and Methods: Subgingival plaque samples were collected from 504 adult volunteers. Probing pocket depths (PPD) and relative attachment levels were measured using an automated probe. Participants were matched for disease status (CPI), plaque index, age and gender, and allocated to receive either a triclosan/copolymer or placebo dentifrice. Re-examination and subgingival plaque sampling was repeated after 1, 2, 3, 4 and 5 years. P. gingivalis, A. actinomycetemcomitans and P. intermedia were detected and quantitated using an enzyme linked immunosorbent assay. Logistic regression and generalised linear modelling were used to analyse the data. Results: This 5-year longitudinal study showed considerable volatility in acquisition and loss (below the level of detection) of all three organisms in this population. Relatively few subjects had these organisms on multiple occasions. While P. gingivalis was related to loss of attachment and to PPD greater than or equal to3.5 mm, there was no relationship between A. actinomycetemcomitans or P. intermedia and disease progression over the 5 years of the study. Smokers with P. gingivalis had more PPD greater than or equal to3.5 mm than smokers without this organism. There was no significant effect of the triclosan dentifrice on P. gingivalis or A. actinomycetemcomitans . Subjects using triclosan were more likely to have P. intermedia than those not using the dentifrice; however this did not translate into these subjects having higher levels of P. intermedia and its presence was uniform showing no signs of increasing over the course of the study. Conclusion: The present 5-year longitudinal study has shown the transient nature of colonisation with P. gingivalis , A. actinomycetemcomitans and P. intermedia in a normal adult population. The use of a triclosan-containing dentifrice did not lead to an overgrowth of these organisms. The clinical effect of the dentifrice would appear to be independent of its antimicrobial properties.

Photosynthetic light and temperature responses of Eucalyptus cloeziana and Eucalyptus argophloia

Acclimation of gas exchange to temperature and light was determined in 18-month-old plants of humid coastal (Gympie) and dry inland ( Hungry Hills) provenances of Eucalyptus cloeziana F. Muell., and in those of a dry inland provenance of Eucalyptus argophloia Blakely. Plants were acclimated at day/night temperatures of 18/13, 23/18, 28/23 and 33/ 28 degreesC in controlled-temperature glasshouses for 4 months. Light and temperature response curves were measured at the beginning and end of the acclimation period. There were no significant differences in the shape and quantum-yield parameters among provenances at 23, 28 and 33 degreesC day temperatures. Quantum yield [mumol CO2 mumol(- 1) photosynthetic photon flux density (PPFD)] ranged from 0.04 to 0.06 and the light response shape parameter ranged from 0.53 to 0.78. Similarly, no consistent trends in the rate of dark respiration for plants of each provenance were identified at the four growth temperatures. Average values of dark respiration for the plants of the three provenances ranged from 0.61 to 1.86 mumol m(-2) s(-1). The optimum temperatures for net photosynthesis increased from 23 to 32 degreesC for the humid- and from 25 to 33 degreesC for the dry-provenance E. cloeziana and from 21 to 33 degreesC for E. argophloia as daytime temperature of the growth environment increased from 18 to 33 degreesC. These results have implications in predicting survival and productivity of E. cloeziana and E. argophloia in areas outside their natural distribution.

Epizootic activity of Murray Valley encephalitis and Kunjin viruses in an aboriginal community in the Southeast Kimberley region of Western Australia: Results of mosquito fauna and virus isolation studies

We undertook annual surveys of flavivirus virus activity in the community of Billiluna of Western Australia in the southeast Kimberley region between 1989 and 2001. Culex annulirostris was the dominant mosquito species, particularly in years of above average rains and flooding. Murray Valley encephalitis (MVE) virus was isolated in 8 of the 13 years of the study from seven mosquito species, but more than 90% of the isolates were from Cx. annulirostris. The results suggest that MVE virus is epizootic in the region, with activity only apparent in years with average or above average rainfall and increased numbers of Cx. annulirostris. High levels of MVE virus activity and associated human cases were detected only once (in 1993) during the survey period. Activity of MVE virus could only be partially correlated with wet season rainfall and flooding, suggesting that a number of other factors must also be considered to accurately predict MVE virus activity at such communities.

Environmental conditions and variation in levels of sun exposure among children in child care

Sun exposure in childhood is I of the risk factors for developing skin cancer, yet little is known about levels of exposure at this age. This is particularly important in countries with high levels of ultraviolet radiation. (UVR) such as Australia. Among 49 children 3 to 5 years of age attending child care centers, UVR exposure was studied under 4 conditions in a repeated measures design; sunny days, cloudy days, teacher's instruction to stay in the shade, and a health professionals instruction to apply sunscreen. Three different data collection methods were employed: (a) completion of questionnaire or diary by parents and researcher, (b) polysulphone dosimeter readings, and (c) observational audits (video recording). Results of this study indicated that more than half the children had been sunburnt (pink or red) and more than a third had experienced painful sunburn (sore or tender) in the last summer. Most wore short sleeve shirts, short skirts or shorts and cap, that do not provide optimal levels of skin protection. However, sunscreen was applied to all exposed parts before the children went out to the playground. Over the period of I hr (9-10 a.m.) the average amount of time children spent in full sun was 22 min. On sunny days there was more variation across children in the amount of sun exposure received. While the potential amount of UVR exposure for young children during the hour they were outside on a sunny day was 1.45 MED (Minimum Erythemal Dose), they received on average 0.35 MED, which is an insufficient amount to result in an erythemal response on fair skin even without the use of sunscreen.