Rotation of a single molecule within a supramolecular bearing

Experimental visualization and verification of a single-molecule rotor operating within a supramolecular bearing is reported. Using a scanning tunneling microscope, single molecules were observed to exist in one of two spatially defined states laterally separated by 0.26 nanometers. One was identified as a rotating state and the other as an immobilized state. Calculations of the energy barrier for rotation of these two states show that it is below the thermal energy at room temperature for the rotating state and above it for the immobilized state.     

对越南卧室家具征收反倾销税的可能性

8月中旬,越南政府官员与家具制造商讨论了美国会不会像对中国的卧室家具那样,对来自越南的卧室家具征收反倾销税。虽然这已是推测已久的议题,答案还不能肯定。     

Serum Levels of Cardiac Markers NT‐proANP and NT‐proBNP in Brachycephalic bitches at Different Gestational Stages

The aim of this study was to determine serum levels of natriuretic peptide precursors (NT‐proANP and NT‐proBNP) during pregnancy in brachycephalic bitches. Fifteen healthy multiparous bitches were selected for this prospective study. Serum levels of NT‐proANP and NT‐proBNP were measured during anoestrous and at 14, 35, 42, 49 and 56 days (2nd, 5th, 6th, 7th and 8th weeks) of pregnancy. Fourteen animals had normal gestations, and one bitch developed single foetus syndrome. The natriuretic peptide levels of this animal were not included in this study; however, it is important to report that its NT‐proANP levels were four times greater than those of normal patients. There was no significant difference (p = 0.072) in NT‐proBNP levels between anoestrous (0.20 ± 0.10 ng/ml) and the different pregnancy weeks (0.27 ± 0.12 ng/ml). There was a positive correlation (p < 0.0001) between NT‐proANP and gestational age, and the levels of this marker increased significantly (p < 0.0001) during the 6th (0.26 ± 0.06 ng/ml), 7th (0.28 ± 0.04 ng/ml) and 8th weeks (0.29 ± 0.05 ng/ml) when compared to anoestrous (0.18 ± 0.02 ng/ml). NT‐proANP serum levels are correlated with gestational development and may be indicative of cardiovascular adaptation in canine brachycephalic pregnancy.     

Australian veterinarians who work with horses: an analysis

OBJECTIVE: To define and describe the population of Australian veterinarians who work with horses. METHOD: Questionnaires were mailed to 866 veterinarians who had been identified as working with horses, and 87% were completed and returned. Data were entered onto an Excel spreadsheet, and analysed using the SAS System for Windows. RESULTS: About 12% of Australia's veterinarians were doing all the veterinary work with horses, and about 3% worked exclusively (> 90%) with horses, but did more than half (58%) of the horse work. Veterinarians working with horses included more males (80%) than the veterinary population as a whole (approximately 60%). Males had an average age of 47 years, females 35. Almost all (94%) worked in private practice, with 31% being employees, 28% partners and 41% sole owners. Females were more likely to be employees than males. Males reported working 55 hours/week; females 49. More females (44%) than males (16%) had worked less than full-time for more than a year. Males expected to work for another 12 years in full-time equivalents, and females for 16. One quarter (24%) saw only horses, but treated 58% of total horse cases. One-half had < 25% horses, and 29% had < 10% of horses in their caseloads. More of the older (54% of those aged > 60) than younger respondents (27% of those < 40) had grown up on farms with animals. One-quarter (24%) decided to become a veterinarian while in primary school, and females decided at a younger age than males. Overall, younger respondents decided at a younger age than did their older counterparts. A veterinarian contributed to the decision for 21% of these veterinarians. CONCLUSION: In this survey, Australian veterinarians who work with horses were found to be typically male, and advanced in their careers. As these older veterinarians retire, there may not be enough veterinarians who are committed to and competent with horses to take their places.     

Longitudinal study of veterinarians from entry to the veterinary course to 10 years after graduation: attitudes to work,career and profession

OBJECTIVE: To describe the attitudes of veterinarians to their work, career and profession during the 10 years after graduation. DESIGN: Longitudinal study of students who started their course at The University of Queensland in 1985 and 1986, and who completed questionnaires in their first and fifth year as students, and after one, five and 10 years as veterinarians. METHODS: Data from 129 (96%) questionnaires completed after 10 years as a veterinarian were coded numerically then analysed, together with data from previous questionnaires, with SAS System 7 for Windows 95. RESULTS: After 10 years, almost all respondents were either very glad they had done the veterinary course (57%) or generally glad, though with some misgivings (37%). Despite this, only 55% would definitely become a veterinarian if they 'had to do it over again'. The responses for about one-third were different from those given five years earlier. The views of many were related to the level of support and encouragement received in their first job after graduation. There were 42% who were working less than half-time as veterinarians, and their main reasons were, in order, raising children, long hours of work, attitudes of bosses and clients, and poor pay. A majority was concerned about the ethics and competence of some colleagues, and almost all believed that consideration of costs must influence the type of treatment animals receive. CONCLUSIONS: Most veterinarians were glad to have done the veterinary course, but for about one-quarter their career had not lived up to expectations and almost half would not do it again in another incarnation. Stress, hours of work, difficulties in balancing personal life with career and low income were important concerns for many. Low income may contribute to the low number of males entering the veterinary profession.