Design and synthesis of N-(2,4=difluorophenyl)-2-(3-trifluoromethylphenoxy)-3-pyridinecarboxamide (diflufenican), a novel pre- and early post-emergence herbicide for use in winter cereals     

Michael C. Cramp  James Gilmour  Leslie R. Hatton  Richard H. Hewett  Christopher J. Nolan  Edgar W. Parnell 《Pest management science》1987,18(1):15-28

The pre- and early post-emergence herbicidal activity of diflufenican, a novel herbicide, is reported and attention is drawn to its ability to control important weeds in winter cereals, including Galium aparine, Veronica hederifolia, Veronica persica and Viola arvensis, which are resistant to substituted-urea herbicides. The synthesis of a series of related compounds is described and the relationship between structure and activities against a range of plant species is examined in respect of changes in the phenyl, phenoxy and pyridine rings. The design and synthesis of a small number of compounds combining the best patterns of substitution in each of the rings is described. The resulting optimisation of herbicidal activity in the series is reported, together with field trial results comparing the herbicidal efficacy, crop selectivity and soil persistence of the most active structures.  相似文献   

Ultrasonography to investigate the effect of supplementing whole milk with complex carbohydrates and specific amino acids on curd retention in the abomasum of dairy calves     

K Singh  SR Leath  HV Henderson  TJ Watson  D Pacheco 《New Zealand veterinary journal》2016,64(5):288-292

AIM: To determine whether the retention time of curd in the abomasum of calves was influenced by supplementing milk with a plant-derived carbohydrate and amino acid supplement, evaluated non-invasively using ultrasonography.

METHODS: Female dairy calves aged between 2–6 days of age were sourced from a commercial farm in March 2013. All calves were fed whole milk until weaning (4?L per day); 21 calves were supplemented with a probiotic until 18 days of age, and thereafter with a plant-derived complex carbohydrate and amino acid supplement until weaning, and 22 calves were just fed whole milk. Treatment groups were balanced for age, weight and breed. At 9–14, 24–29 and 52–57 days of age, the abomasum of each calf was examined using ultrasonography immediately before and after feeding, 1 and 2 hours after feeding, and then at 30 minute intervals until curd was no longer visible in the abomasum. Abomasal volume and curd size were recorded to assess retention time of curd in the abomasum.

RESULTS: At 9–14 days of age, mean retention time of curd in the abomasum was similar (4.6 hours) in both groups. At 24–29 days of age, when the supplemented calves had been receiving the supplement for approximately 10 days, mean curd retention time was longer by 1.4 (SE 0.28) hours in supplemented compared with unsupplemented calves (p<0.001). At 52–57 days of age, mean retention time was longer by 0.7 (SE 0.34) hours compared to unsupplemented calves (p=0.05).

CONCLUSION: Using ultrasonography, changes in abomasal content could be followed non-invasively over time and it was demonstrated that the plant-derived complex carbohydrate supplement increased the curd retention time in the abomasum. We speculate that the increased retention time enables an increased availability of nutrients following a more complete digestion of milk, thereby improving animal performance.  相似文献   

Effects of GnRH,a progesterone‐releasing device,and energy balance on an oestrus synchronisation program in anoestrous dairy cows          下载免费PDF全文

SK Sahu  JF Cockrem  TJ Parkinson  RA Laven 《Australian veterinary journal》2017,95(8):281-288

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Strong enhancement of nonlinear optical properties through supramolecular chirality     

T Verbiest  SV Elshocht  M Kauranen  L Hellemans  J Snauwaert  C Nuckolls  TJ Katz  A Persoons 《Science (New York, N.Y.)》1998,282(5390):913-915

A new approach to second-order nonlinear optical (NLO) materials is reported, in which chirality and supramolecular organization play key roles. Langmuir-Blodgett films of a chiral helicene are composed of supramolecular arrays of the molecules. The chiral supramolecular organization makes the second-order NLO susceptibility about 30 times larger for the nonracemic material than for the racemic material with the same chemical structure. The susceptibility of the nonracemic films is a respectable 50 picometers per volt, even though the helicene structure lacks features commonly associated with high nonlinearity. Susceptibility components that are allowed only by chirality dominate the second-order NLO response.  相似文献   

Loss of intraspecific aggression in the success of a widespread invasive social insect     

DA Holway  AV Suarez  TJ Case 《Science (New York, N.Y.)》1998,282(5390):949-952

Despite the innumerable ecological problems and large economic costs associated with biological invasions, the proximate causes of invasion success are often poorly understood. Here, evidence is provided that reduced intraspecific aggression and the concomitant abandonment of territorial behavior unique to introduced populations of the Argentine ant contribute to the elevated population densities directly responsible for its widespread success as an invader. In the laboratory, nonaggressive pairs of colonies experienced lower mortality and greater foraging activity relative to aggressive pairs. These differences translated into higher rates of resource retrieval, greater brood production, and larger worker populations.  相似文献   

Stocks for the Stone Fruits     

Ronald G. Hatton 《The Journal of Horticultural Science and Biotechnology》2013,88(4):209-245

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A longitudinal study of veterinary students and recent graduates 4. Gender issues   总被引：2，自引：1，他引：1  

TJ HEATH  A. LANYON 《Australian veterinary journal》1996,74(4):305-308

Objective To study differences in experiences, attitudes and opinions between female and male veterinary students and recent graduates.
Design Longitudinal study.
Population Students – 77 males and 77 females – who began studying veterinary science at The University of Queensland in 1985 and 1986.
Procedure Questionnaires were completed in the first and fifth year of the course, and in the second year after graduation. The data were analysed using the SAS System for Windows.
Results Females decided to study veterinary science at a younger age than males and were more influenced by 'a love of animals', the image of veterinarians as portrayed on television, an interest in living things and in the scientific study of disease. Males were more influenced than females in aspects of the workplace: bosses and money. There were no gender differences in their background in relation to farms, or to animals, or in their career plans. However females when in first year expected a lower initial income than males; an expectation that was realised in the first year after graduation. As first year students and also as veterinarians, females had stronger views than males on animal welfare issues, and also felt that the veterinary profession had a lower status relative to other professions.
Conclusions Significant differences in attitudes and experiences exist between males and females entering the veterinary profession. The situation of females in relation to income and status is consistent with that in other professions, where females have been disadvantaged compared with males.  相似文献   

Monitoring and surveillance in abattoirs of residues of antibacterial substances – a description of programs in Australia and the USA     

JL CUPIT  NL BLACKMAN†  TJ NICHOLLS†  IB STEPHENS†  RJ WILD 《Australian veterinary journal》1994,71(12):400-403

SUMMARY Australia and the USA are major international meat exporting countries. Both countries conduct programs to monitor and survey for antibacterial residues. Australian programs use a urine screening test, whereas the US programs use tissue fluids as the test medium. The development of surveillance programs to provide rapid feedback to producers is a feature of the Australian programs. The programs in each country compare favourably with regard to numbers of animals tested, results and action taken to prevent residues. The results of the Australian programs justify the promotion of a ‘clean food’ image for Australian meat products with respect to antibacterial drugs.  相似文献   

A longitudinal study of veterinary students and recent graduates 2. Views of the veterinary profession   总被引：1，自引：1，他引：0  

TJ HEATH  M. LYNCH-BLOSSE  A. LANYON 《Australian veterinary journal》1996,74(4):297-300

Objective To examine the development of attitudes and opinions relating to the veterinary profession.
Design Longitudinal study.
Population Students, 154 in all, who began studying veterinary science at The University of Queensland in 1985 and 1986.
Procedure Questionnaires were completed in the first and fifth year of the course and in the second year after graduation. The data were analysed using the SAS System for Windows.
Results Few changes in opinion over time were found on the role of the profession, or on the status and prestige of veterinarians. Changes did occur in views on the characteristics of a successful veterinarian, with increases in the perceived importance of interpersonal skills, and of the capacity to work hard, and decreases in the perceived importance of honesty and integrity, dedication and the prevention of cruelty. Attitudes hardened over time in relation to costs of treatment, non-payment of fees and availability out of hours. Individuals changed their opinion on whether to counsel or report an incompetent colleague, but the changes in one direction were approximately equal to those in the opposite direction.
Conclusions The attitudes and opinions of veterinary graduates result from experiences before and during their veterinary course. In general the perceived importance of interpersonal skills increases during the course, and the level of altruism decreases.  相似文献   

Integration of sapflow velocity to estimate plant water use     

Hatton TJ  Catchpole EA  Vertessy RA 《Tree physiology》1990,6(2):201-209

The heat pulse technique provides an estimate of sapflow velocity at one position within the xylem of an individual plant. Previous experience has shown that the velocity profile across the conducting area cannot be assumed to be constant, necessitating several such point estimates for a reasonable characterization of the velocity profile with depth. These point estimates must be integrated over the sapwood conducting area to derive flux. The most common method is to fit a one degree of freedom least-squares polynomial to the point estimates, and then to integrate this equation across the sapwood profile and around the bole. An alternative method is presented based on a weighted average approach. The latter is shown to be a more robust estimator of flux when velocity profiles exhibit large curvatures.  相似文献