Electrical conductivity of olivine, wadsleyite, and ringwoodite under upper-mantle conditions

Geophysical models show that electrical conductivity in Earth's mantle rises about two orders of magnitude through the transition zone in the depth range 410 to 660 kilometers. Impedance measurements obtained on Mg1.8Fe0.2SiO4 olivine, wadsleyite, and ringwoodite at up to 20 gigapascals and 1400 degreesC show that the electrical conductivities of wadsleyite and ringwoodite are similar and are almost two orders of magnitude higher than that of olivine. A conductivity-depth profile to 660 kilometers, based on these laboratory data, shows a conductivity increase of almost two orders of magnitude across the 410-kilometer discontinuity; such a profile favors a two-layer model for the upper mantle. Activation enthalpies of 1.2 to 1.7 electron volts permit appreciable lateral variations of conductivity with lateral temperature variations.     

A longitudinal study of veterinary students and recent graduates 4. Gender issues

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.     

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

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.     

A longitudinal study of veterinary students and recent graduates 2. Views of the veterinary profession

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.     

Effect of sucralfate on total carbon dioxide concentration in horses subjected to a simulated race test

The purpose of this study was to test the hypothesis that sucralfate, a gastric ulcer medication, would alter plasma concentrations of total carbon dioxide (tCO2), lactate (LA), sodium (Na+), potassium (K+), chloride (Cl-) and total protein (TP), as well as calculated plasma strong ion difference (SID) and packed cell volume (PCV) in horses subjected to a simulated race test (SRT). Six unfit Standardbred mares (approximately 520 kg, 9-18 years) were used in a randomized crossover design with the investigators blinded to the treatment given. The horses were assigned to either a control (40-50 mL apple sauce administered orally (PO)) or a sucralfate (20 mg/kg bodyweight dissolved in 40-50 mL apple sauce administered PO) group. Each horse completed a series of SRTs during which blood samples were taken via jugular venipuncture at five sampling intervals (prior to receiving treatment, prior to SRT, immediately following exercise, and at 60 and 90 min post-SRT). During the SRTs, each horse ran on a treadmill fixed on a 6% grade for 2 min at a warm-up speed (4 m/s) and then for 2 min at a velocity predetermined to produce VO2max. Each horse then walked at 4 m/s for 2 min to complete the SRT. Plasma tCO2, electrolytes, LA, and blood PCV and TP were analysed at all intervals. No differences (P>0.05) were detected between control and sucralfate for any of the measured variables. There were differences (P<0.05) in tCO2, SID, PCV, TP, LA and electrolyte concentrations relative to sampling time. However, these differences were attributable to the physiological pressures associated with acute exercise and were not an effect of the medication. It was concluded that sucralfate did not alter plasma tCO2 concentration in this study.     

Immune-mediated haemolytic anaemia in 110 dogs in Victoria, Australia

Objective   Evaluate the survival and prognostic indicators (i.e. breed predilection, season, blood transfusion, and the prevalence of autoagglutination) of dogs with immune-mediated haemolytic anaemia (IMHA) in Victoria, Australia.
Design   Retrospective study of 110 diagnosed with primary IMHA at the University of Melbourne Veterinary Clinic and Hospital.
Results   In total, 80 of the dogs (72.7%) were discharged from hospital and 48 of 65 (73.8%) dogs available for follow-up were known to be alive at 1 year, giving an overall 1-year survival of 48 (50.5%) of 95 dogs for which survival data were available. Regarding breed, 80 (18.2%) of the 110 dogs were Maltese-breed dogs compared with 81 (7.4%) of 1100 control dogs (P < 0.001). Springer Spaniels (P = 0.02), Hungarian Vizslas (P = 0.02) and Airedale Terriers (P < 0.001) were also over-represented compared with the control sample. There was no evidence of an association between the occurrence of IMHA in dogs and season in this study. Receiving one or more blood transfusions did not affect survival to the time of discharge from hospital. On initial blood smear examination, 57 (51.8%) of the 110 dogs had spontaneous autoagglutination and its presence was associated with decreased survival to discharge from hospital (P = 0.03). Packed cell volume, white cell count, platelet count and serum total bilirubin on admission had no effect on survival to the time of discharge from hospital or 1 year later.
Conclusion   Dogs with IMHA have a guarded prognosis as only half are still alive 1 year after the acute event.     

求真务实扎实工作坚持科学发展观积极推进全国兽药监察工作--在全国兽药监察所所长会议上的讲话

同志们: 正值"两会"和全党开展"保持共产党员先进性教育活动"期间,全国兽药监察所所长会议在石家庄市召开.这次会议的主要任务是:以保持共产党员先进性教育为契机,全面贯彻全国农业工作会议畜牧兽医专业会议精神和新颁布的<兽药管理条例>,认真总结2004年全国兽药质量监督工作,进一步分析兽药质量监督工作面临的新形势,研讨2005年的工作重点,坚持科学发展观,创新兽药监察工作思路,大力推进兽药监察工作.     

美国、加拿大生物安全三级动物实验室考察报告

美国、加拿大对ABSL-3的设计均为三层。下方的尸体、污物处理层和上方的设备层及中间的动物实验室层。设计比较科学，人性化，其高度均达6m以上。配备有索道和电葫芦，以供动物移动使用；电动解剖台可按电钮升降调节解剖台的高度，动物尸体处理由Renderer cooker尸体处理器经高压、粉碎、干燥成肉陷状颗粒，粪便及污水收集在三个5000L容量的高压灭菌处理器中高压灭菌处理，设施内的灭菌采用环保的过氧化氢消毒设备。     

Transcutaneous ultrasound over the right flank to diagnose mid- to late-pregnancy in the dairy cow

Objective   To investigate the practical application and image quality of transcutaneous ultrasonography across the right flank for the diagnosis of mid- to late-gestation in cattle.
Procedure   Dairy cows of known pregnancy status were used to establish criteria for the identification of mid- to late-stage pregnancy by transcutaneous ultrasonography. Factors involved in the practical application of transcutaneous ultrasound for routine use in pregnancy diagnosis in dairy cattle were also examined.
Results   Transcutaneous ultrasound, using a 3.5-MHz sector transducer applied over the caudodorsal right flank fold, allowed rapid and detailed visualisation of bovine pregnancy (i.e. fetus, fetal fluids, placentomes and/or fetal membranes) and could be used to establish criteria for the diagnosis of pregnancy. The commonly available cattle holding facilities of the herringbone dairy, rotary herringbone dairy, AI race or crush, and walk-through dairy all allow safe access to the right flank of a dairy or beef cow. However, transcutaneous scanning over the right flank is difficult in modern rotary turnstile dairies.
Conclusion   A 3.5-MHz sector transducer applied over the caudodorsal right flank fold allows detailed visualisation of the bovine fetus in most types of cattle-holding facilities. Further investigation of the sensitivity and specificity of this technique over the entire gestation period and its possible use in ageing of the bovine fetus is merited.