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1.
Britt T Weisse C Weber ES Matzkin Z Klide A 《Journal of the American Veterinary Medical Association》2002,221(5):690-3, 645
A Ryukin goldfish was evaluated because of a 6-month history of progressive abdominal distention and positive buoyancy. Overinflation of the swim bladder was diagnosed, and the fish was anesthetized with tricaine methanesulfonate. Archimedes' principle was used to determine the volume of swim bladder that was removed surgically. The caudal swim bladder was exteriorized through an abdominal incision and 2 surgical clips were placed across it to limit its size. After surgery, the fish remained in a state of negative buoyancy in sternal and lateral recumbency on the bottom of the tank. Sutures were removed 15 days after surgery, but the fish died 24 days after surgery. A full necropsy could not be performed because of autolysis of the tissues, but the surgical clips and the swim bladder appeared unremarkable. Pneumocystoplasty may be a viable treatment for this condition. 相似文献
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Molybdenum nanowires by electrodeposition 总被引：1，自引：0，他引：1
Metallic molybdenum (Mo(o)) wires with diameters ranging from 15 nanometers to 1.0 micrometers and lengths of up to 500 micrometers (0.5 millimeters) were prepared in a two-step procedure. Molybdenum oxide wires were electrodeposited selectively at step edges and then reduced in hydrogen gas at 500 degrees C to yield Mo(o). The hemicylindrical wires prepared by this technique were self-uniform, and the wires prepared in a particular electrodeposition (in batches of 10(5) to 10(7)) were narrowly distributed in diameter. Wires were obtained size selectively because the mean wire diameter was directly proportional to the square root of the electrolysis time. The metal nanowires could be embedded in a polystyrene film and lifted off the graphite electrode surface. The conductivity and mechanical resiliency of individual embedded wires were similar to those of bulk molybdenum. 相似文献
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L W Cook F W Zach J R Fleeker 《Journal of the Association of Official Analytical Chemists》1982,65(2):215-217
A procedure based on steam distillation is described for the determination of residues of the thiocarbamate herbicides diallate and triallate. The herbicides are steam-distilled directly from aqueous suspensions of milk and plant samples and trapped in hexane. After column cleanup on either activated Florisil or silica cartridges, samples are quantitated by gas-liquid chromatography. Recoveries of diallate and triallate from milk, lettuce, peas, corn, canarygrass seed and straw, and flax straw ranged from 77 to 96%. 相似文献
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Costello EK Stagaman K Dethlefsen L Bohannan BJ Relman DA 《Science (New York, N.Y.)》2012,336(6086):1255-1262
The human-microbial ecosystem plays a variety of important roles in human health and disease. Each person can be viewed as an island-like "patch" of habitat occupied by microbial assemblages formed by the fundamental processes of community ecology: dispersal, local diversification, environmental selection, and ecological drift. Community assembly theory, and metacommunity theory in particular, provides a framework for understanding the ecological dynamics of the human microbiome, such as compositional variability within and between hosts. We explore three core scenarios of human microbiome assembly: development in infants, representing assembly in previously unoccupied habitats; recovery from antibiotics, representing assembly after disturbance; and invasion by pathogens, representing assembly in the context of invasive species. Judicious application of ecological theory may lead to improved strategies for restoring and maintaining the microbiota and the crucial health-associated ecosystem services that it provides. 相似文献
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Sefczek TM Farris ZJ Wright PC 《Folia primatologica; international journal of primatology》2012,83(1):1-10
In this research, we focused on aye-aye populations in Ranomafana National Park, Madagascar. From August to December 2008, we tested how aye-aye feeding was influenced by presence/absence of both fruiting and non-fruiting Canarium trees. Deadwood feeding traces were used as a proxy for evidence of Canarium feeding. We enumerated deadwood feeding traces in 20 locations, 10 with Canarium, 10 without. Each location contained two transects (80 m L × 20 m W) for a total area of 5.6 ha. Feeding trace results for Canarium locations compared to non-Canarium locations were not significant (Z = -1.926, p = 0.083); however, feeding trace results were significant when comparing fruiting and non-fruiting Canarium locations (Z = -2.417, p = 0.016). These results highlight the importance of Canarium in the diet of aye-ayes and demonstrate how the distribution of this resource may influence the foraging behavior of aye-ayes. 相似文献
7.
Salt cedar (Tamarix spp.) readily invades and dominates riparian areas and lake basins throughout the western United States. Traditional control efforts (chemical and mechanical control) are expensive and provide limited long-term control. The salt cedar leaf beetle (Diorhabda elongata) provides a method of biological control through reduction in cover. However, population establishment of leaf beetles in some locations is often difficult because of environmental conditions. In previous research, goats readily consumed salt cedar, offering an alternative method of reducing salt cedar cover. For this study, we determined if sheep would consume salt cedar and consume a similar amount as goats. Twelve Rambouillet and 12 Suffolks lambs were fed salt cedar once daily (Trial 1) and three times daily (Trial 2). Intake of salt cedar by sheep was compared between breeds and with intake of salt cedar by goats (n = 10). Salt cedar was fed once a day in Trial 1 for 30 min over 15 d. Intake was recorded daily for individual animals. In Trial 2, salt cedar was offered three times daily for 13 d with intake recorded. There were no differences (P > 0.05) between breeds of sheep. In addition, sheep consumed more salt cedar than goats except on the last day of the study. When salt cedar was offered three times daily, both breeds of sheep increased intake and gained weight over the 13 d of feeding in Trial 2. By the end of the study, intake appeared to still be increasing. Collectively, these results illustrate that both Rambouillet and Suffolk sheep will consume a similar amount of salt cedar as goats and will provide another species of livestock that can be potentially used to reduce salt cedar cover. 相似文献
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Gene Stevens Matthew Rhine Zach Straatmann David Dunn 《Communications in Soil Science and Plant Analysis》2016,47(18):2148-2155
Most laboratories make potassium (K) fertilizer recommendations based on field research calibrated with soil K from atomic absorption spectroscopy, flame emission spectroscopy, or inductively coupled plasma mass spectrometry. Information is needed to interpret readings from K+ meters on cotton. The objective was to compare soil and cotton plant sap potassium content from a Laqua Twin? K+ meter to results from standard tests. Aluminum sulfate solution was used with the meter to extract K from 10 soil samples from the North America Proficiency Testing program. A linear relationship (R2 = 0.86) was found between K measured with a K+ meter and K measured with 138 labs using ammonium acetate or Mehlich-3. Using a factor of 1.4754 to adjust readings, fertilizer recommendations with the K+ meter were similar to results from atomic absorption spectroscopy. A linear relationship was found between petiole K measured in the lab and petiole sap measured with the K+ meter. 相似文献
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We studied the leaf litter-dwelling fauna of managed deciduous forests and primeval reference sites in Western and Central Europe and addressed the questions if the higher overall species richness close to downed coarse woody debris (CWD) is related to intra-specific or inter-specific aggregation, if the aggregation pattern changes with the amount of CWD on the forest floor, and how much CWD is needed for different taxa. The analysis is based on shelled Gastropoda, Diplopoda/Isopoda, Chilopoda and Coleoptera. Among-sample heterogeneity was lower close to CWD than distant from CWD. This was most pronounced in Diplopoda/Isopoda and Gastropoda. Diplopoda/Isopoda are comparatively mobile and assemblages were already quite homogenous close to CWD at levels above 5 m3 downed deadwood ha−1. Gastropoda have a low mobility, and more than 20 m3 downed deadwood ha−1 is needed for assemblage homogeneity. We further focused on the Gastropoda as sensitive indicators. Enhanced densities and species richness close to CWD were not a simple function of leaf litter weight, thus effects of densities on heterogeneity are not solely driven by leaf litter accumulation close to CWD. In contrast to euryecious litter-dwellers such as the Punctidae, stenecious slow active dispersers such as the Clausiliidae clearly require more than 20 m3 CWD ha−1 for an even distribution. Specialists depending on CWD even seem to have gone extinct in some managed forests. For conserving the litter-dwelling fauna, we propose a target of at least 20 m3 downed CWD ha−1 in already managed forests and rigorous restrictions for deadwood removal from still (almost) pristine systems. 相似文献
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Hayden R Kerkaert Henrique S Cemin Jason C Woodworth Joel M DeRouchey Steve S Dritz Mike D Tokach Robert D Goodband Keith D Haydon Chad W Hastad Zach B Post 《Journal of animal science》2021,99(1)
Based on results of a recent meta-analysis, we hypothesized that increased dietary Val, Ile, or Trp could correct possible amino acid interactions because of excess Leu in diets containing high levels of corn protein, namely dried distiller’s grains with solubles (DDGS). A total of 1,200 pigs (PIC TR4 × (Fast LW × PIC L02); initially 33.6 ± 0.6 kg) were used in a 103-d study. The 6 dietary treatments were corn–soybean meal (SBM)-DDGS-based as follows: (1) high SBM and low level of l-Lys HCl (HSBM), (2) high l-Lys HCl and moderate Ile, Val, Trp (AA above NRC 2012 estimates; NC), (3) moderate l-Lys HCl and high Ile, Val, and Trp (PC), and PC with either increased (4) L-Val (PC+Val), (5) L-Ile (PC+Ile), or (6) L-Trp (PC+Trp). Pigs fed the NC diet were predicted to have the poorest average daily gain (ADG), the PC diet to be intermediate, and pigs fed the HSBM, PC+Val, PC+Ile, and PC+Trp have the same and highest predicted ADG. In the grower period (34 to 90 kg), ADG was greater (Ρ < 0.05) for the pigs fed HSBM and PC+Val diets than the NC with pigs fed other diets intermediate. Pigs fed HSBM were more (Ρ < 0.05) efficient (G:F) than the NC and PC with pigs fed other diets intermediate. In the finisher period (90 to 136 kg), ADG was greater (Ρ < 0.05) for pigs fed PC+Ile than that of the NC with pigs fed other diets intermediate. Pigs fed PC+Val had greater (Ρ < 0.05) average daily feed intake (ADFI) than the NC with pigs fed other diets intermediate. However, PC+Ile pigs were more (Ρ < 0.05) efficient than PC+Val with pigs fed other diets intermediate. Overall, ADG was greater (Ρ < 0.05) for pigs fed HSBM, PC+Val, and PC+Ile diets than the NC with pigs fed other diets intermediate. Pigs fed the PC+Val diet had greater (Ρ < 0.05) ADFI than the NC with pigs fed other diets intermediate. No differences were detected between treatments for overall G:F or other carcass characteristics. In conclusion, increasing Val or Ile in high l-Lys-HCl-DDGS-based diets improved growth performance compared with pigs fed diets containing high levels of l-Lys HCl without added Val and Ile. These results present evidence that the recently developed meta-analysis can predict the relative differences in overall ADG for pigs fed the NC, PC, PC+Val, and PC+Ile diets; however, the predicted G:F was less accurate. The data demonstrate that the negative effects of high Leu concentrations in corn-DDGS-based diets can be reversed by increasing the ratios of Val and Ile relative to Lys. 相似文献