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Level Profiles (level + profile)
Selected AbstractsEVALUATION OF A STREAM AQUIFER ANALYSIS TEST USING ANALYTICAL SOLUTIONS AND FIELD DATA,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 3 2004Garey A. Fox ABSTRACT: Considerable advancements have been made in the development of analytical solutions for predicting the effects of pumping wells on adjacent streams and rivers. However, these solutions have not been sufficiently evaluated against field data. The objective of this research is to evaluate the predictive performance of recently proposed analytical solutions for unsteady stream depletion using field data collected during a stream/aquifer analysis test at the Tamarack State Wildlife Area in eastern Colorado. Two primary stream/aquifer interactions exist at the Tamarack site: (1) between the South Platte River and the alluvial aquifer and (2) between a backwater stream and the alluvial aquifer. A pumping test is performed next to the backwater stream channel. Drawdown measured in observation wells is matched to predictions by recently proposed analytical solutions to derive estimates of aquifer and streambed parameters. These estimates are compared to documented aquifer properties and field measured streambed conductivity. The analytical solutions are capable of estimating reasonable values of both aquifer and streambed parameters with one solution capable of simultaneously estimating delayed aquifer yield and stream flow recharge. However, for long term water management, it is reasonable to use simplified analytical solutions not concerned with early-time delayed yield effects. For this site, changes in the water level in the stream during the test and a varying water level profile at the beginning of the pumping test influence the application of the analytical solutions. [source] Plasma cortisol and metabolite level profiles in two isogenic strains of common carp during confinementJOURNAL OF FISH BIOLOGY, Issue 1 2001N. M. Ruane A rapid increase in common carp Cyprinus carpio plasma cortisol levels was noted, in two experiments, after 30 mins of a 3 h net confinement, which was sustained while the fish were held in the nets. After release from the nets, cortisol levels returned to control values in 1 h. Plasma glucose and free fatty acid levels were elevated by the confinement. Glucose was increased after 30 min but returned to basal levels after 22 h of recovery while free fatty acids were not elevated until 3 h of confinement and remained high for the duration of the recovery period. After confinement for 3 h, plasma lactate levels were reduced and remained low for a further 1 h. No change in either plasma triglyceride or cholesterol levels were found during the study. Confinement had no effect on haematocrit levels but blood haemoglobin levels were reduced. In both experiments hypochloraemia occurred in response to confinement. However, values returned to pre-confinement levels 22 h after confinement. These results show that rearing isogenic carp strains, under identical conditions, results in a reproducable response to an acute stressor and that these carp respond in a similar manner to other teleost species. [source] Comparison of bovine in vivo bioavailability of two sulfamethazine oral boluses exhibiting different in vitro dissolution profilesJOURNAL OF VETERINARY PHARMACOLOGY & THERAPEUTICS, Issue 6 2006M. N. MARTINEZ The bolus (or oblet) is a dosage form that can be used for the oral administration of pharmaceutical compounds to ruminating species. Unlike traditional tablets, oral boluses may contain quantities of drug on the order of grams rather than milligrams. Due to its size, it is only recently that USP-like in vitro dissolution methods have been developed for this dosage form. However, whether or not these dissolution tests can predict product in vivo performance has yet to be determined. The importance of this issue is apparent when the U.S. Food and Drug Administration Center for Veterinary Medicine is faced with the decision of whether to require additional in vivo bioequivalence study data to support the approval of changes in product chemistry or manufacturing method. The current study was undertaken to determine whether an in vivo/in vitro correlation can be established for bovine sulfamethazine oral boluses and to acquire insight into the magnitude of changes in in vitro product performance that can occur before corresponding changes are seen in in vivo blood level profiles. Based upon the results of this investigation, it is concluded that marked changes in in vitro sulfamethazine bolus performance can be tolerated before resulting in altered in vivo blood level profiles. However, the data also suggest that rumenal absorption may occur for some compounds. Therefore the degree to which variation in product in vitro dissolution profiles can be tolerated may be compound specific. [source] Endocrine Profiles and Embryo Quality in Japanese Black Cattle Superovulated with Human Menopausal Gonadotrophin and Porcine Follicle Stimulating HormoneREPRODUCTION IN DOMESTIC ANIMALS, Issue 2 2001M Sugano Induction of superovulation using human menopausal gonadotriphin (hMG) in Japanese Black cattle can result in the recovery of a higher percentage of high quality embryos compared with that using porcine follicle stimulating hormone (FSH). In order to clarify the endocrinological mechanism involved in this discrepancy, 30 superovulation sessions of 17 Japanese Black cattle were studied. Fifteen cattle were super-stimulated with hMG (total 600 IU), and the remaining 15 cattle were given FSH (total 20 mg). The plasma profiles of LH, estradiol-17, (E2) and progesterone (P4) were correlated, and the embryo quality was investigated. The total number of ova recovered and the number of transferable embryos tended to be larger in the hMG-treated group than in the FSH-treated group. The percentage of excellent embryos tended to be higher in the hMG-treated group than in the FSH-treated group (54.3 and 28.7%, respectively, p < 0.10). The E2 level increased during the first 3 days after the initial administration of either hMG or FSH and was higher in the hMG-treated group than in the FSH-treated group (p < 0.05). During this period, the E2 level could be categorized into one of the following three types according to whether it increased or decreased and according to the degree of increase or decrease: (1) increase by a factor of 1.2 or more (quick increase type) (2) slight increase by a factor less than 1.2 (slow increase type), and (3) no increase (unstable increase type). In the group treated with hMG, 66.7% of the animals (10 of 15 cattle) showed a quick increase in the E2 level. However, in the FSH-treated group, 40% (six of 15) of the animals showed a slow increase in the E2 level. The plasma LH level increased dramatically 8 h prior to the peak level in both the hMG- and FSH-treated groups, and then it returned to the basal level 12 h later. After the administration of prostaglandin (PG)F2,, the LH peak level was attained within 44 h in 80% of the animals in the hMG-treated group, whereas in the FSH-treated group, the LH peak level tended to be reached later. The P4 level did not increase during the period of hMG or FSH treatment and decreased drastically following administration of PGF2,. After the onset of oestrus, the P4 level was higher in the hMG group than in the FSH group, and 5 to 7 days after oestrus, the level remained higher in the hMG group than in the FSH group (p < 0.05). After the first 3 days of hMG administration, the E2/P4 ratio was higher than that after FSH administration. Furthermore, on the day following PGF2, administration, the ratio was significantly higher in the hMG group than in the FSH group (p < 0.05). These results indicate that superovulation in cattle given hMG results in a significant increase in plasma E2 during the first 3 days and that the increase in the plasma P4 level is larger a few days after oestrus and thereafter compared with FSH-induced superovulation. Therefore, such plasma level profiles may be related to the increased recovery rate of high quality embryos. [source] | ||||||||||