The Effects of Dexmedetomidine Continuous Rate Infusion (CRI) on Isoflurane Anaesthesia in Healthy Horses

The concept of the modern anaesthesiological technique partial intravenous anaesthesia (PIVA) is by means of infusion of different pharmacological agents as a supplement to inhalation anaesthetics to reduce the concentration of volatile agents maintaining surgical anaesthesia and to decrease their noxious side effects mainly on cardiovascular and respiratory systems. Alpha-2 agonists are agents with frequent use in equine practice either as sedatives or in general anaesthesia PIVA protocols. The most selective amongst them, dexmedetomidine, is characterized by fewer side effects, lower doses, and fast elimination which make it appropriate for application as a continuous rate infusion (CRI). The purpose of this study was to trace out the effects of dexmedetomidine continuous rate infusion (CRI) as part of PIVA using isoflurane on volatile agent requirements, cardiovascular function, respiration and coagulation parameters, and recovery in healthy horses. Six healthy horses with average age 9.0 ± 5.1 year and mean body weight 247.7 ± 71.4 kg were subjected to either 3-hour lasting isoflurane or isoflurane-dexmedetomidine anaesthesia two weeks apart. The main clinical and anaesthesiological parameters were monitored in 10 minutes intervals. Electrolytes, acid-base, blood gases, and coagulation parameters were measured at the beginning and at the end of each anaesthesia. Recovery times and qualities were also recorded. The results showed that, the addition of dexmedetomidine by CRI at 1.75 μg·kg-1·hour-1 to isoflurane anaesthesia slightly reduced isoflurane requirement for maintenance of surgical anaesthesia but had negligible effects on the recovery time and quality. PIVA using dexmedetomidine and isoflurane produced respiratory acidosis similar to isoflurane anaesthesia alone but with significantly more pronounced hypoxaemia and hyperlactaemia. Both investigated anaesthesia protocols did not influence significantly haemocoagulation parameters.

Application of rock mass classification systems to rock slope stability assessment:A case study

The stability of rock slopes is considered crucial to public safety in highways passing through rock cuts, as well as to personnel and equipment safety in open pit mines. Slope instability and failures occur due to many factors such as adverse slope geometries, geological discontinuities, weak or weathered slope materials as well as severe weather conditions. External loads like heavy precipitation and seismicity could play a significant role in slope failure. In this paper, several rock mass classification systems developed for rock slope stability assessment are evaluated against known rock slope conditions in a region of Saudi Arabia, where slopes located in rugged terrains with complex geometry serve as highway road cuts. Selected empirical methods have been applied to 22 rock cuts that are selected based on their failure mechanisms and slope materials. The stability conditions are identified, and the results of each rock slope classification system are compared. The paper also highlights the limitations of the empirical classification methods used in the study and proposes future research directions.

The Multi-Center Comparative Clinical Trial of the Second Generation of Indomethacin VCu and TCu380A

Objective To study the effectiveness and side effects of the modified new indomethacin VCu IUD Material & methods It is a randomized multi-center clinical trial. Indomethacin VCu and TCu380A were inserted in 2 000 healthy women in 6 clinical units including urban and rural area from May 1997 to Feb 1998, with 1 000 cases in each group. Follow up time were 6, 12, and 24 month after insertion. Results The clinical characteristics of subjects in two groups were similar. Follow up was completed in 98.25% of cases. The net cumulative continuous rate at 6 month was 95.5% in TCu380A group and 97.5% in Indomethacin VCu group (P<0.05); at 12 month it was 93.79% and 94.78% respectively; at 24 month it was 88.23% and 89.77% respectively. The expulsion rate was higher in T group than in V group during 24 months. Termination due to pregnancy and bleeding or pain was similar in two groups. The occurrence of menorrahgia, prolonged bleeding and abdominal pain was also higher in T group than that in V group during 24 months after insertion. Spotting was more often in T group in 12 month. On the other hand, more subjects complained hypomenorrhea in V group. The total B/S period, average B/S period and the longest B/S period were all longer in T group during 4～6 month after IUD insertion (P< 0.01). The amount of hemoglobin was similar in two groups before IUD insertion. At the end of study, the amount of hemoglobin in T group decreased compared with baseline (P<0.001), and was lower than V group at the same time (P<0.001), while no change was observed in V group. Conclusion Compared with TCu380A, the second generation of indomethacin VCu possess the same contraceptive effect and cumulative continuous rate and lower side effects such as bleeding and abdominal pain. VCu is more beneficial to reproductive health of women, therefore, is worth of clinical application.

Repetition rate continuously tunable 10-GHz picosecond mode-locked fiber ring laser

A couple of simple-structure phase modulators were used in active mode-locked fiber laser to implement repetition rate continuous tuning. The laser produces pulse as short as 5.7 ps whose repetition rate tuning can cover the spacing of the adjoining order mode-locking frequencies.

Post-marketing Surveillance for Combined Oral Contraceptive Containing Desogestrel(Marvelon~) in Chinese Rural Areas

To assess the side effects and the continuation rate of combined oral contraceptive （COC） containing desogestrel （Marvelon） during 12 months. Methods This was a post-marketing surveillance study on Marvelon COC among 870 healthy rural women in 5 different counties of Jiangsu Province during 12 months. Results About 24.02% of the women who used Marvelon COC experienced side effects during 12 months. Gastrointestinal disorder, bleeding/spotting and chloasma were ranked the first three in the side effects. The rate of side effects of Marvelon COC users during the first 3 months in southern area of Jiangsu was significantly higher than that of users in northern area of Jiangsu. Most of the users did not experience obvious weight changes i.e., loss or increase in weight of more than 5 kg during 12 months. Blood pressure and biochemical indicators of almost 99% among users were within the normal range. The gross cumulative continuation rate for 12 months was 83.14%; the most common medical reason for discontinuation was gastrointestinal disorder. There was an increased risk of discontinuation use among women with lower educational level. Conclusion Marvelon COC brought fewer side effects and was well accepted when applied in Chinese rural women.

Lubricant flow in thin-film elastohydrodynamic contact under extreme conditions

To further extend knowledge about fluid film friction in elastohydrodynamic contact,it is important to examine how lubricant flows.In this paper,several film thickness results obtained by interferometry technique for different kinds of experiments were analyzed and discussed based on lubricant flow continuity.Results of two steady-state and two transient experiments are presented.Possible speed profiles that can explain observed film thickness distributions were suggested.It is shown that major part of present experiments can be explained by a single speed profile known as a plug flow.This finding is in contradiction to usual linear speed profile predicted by Reynolds equation.