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31.
A L Goldberg 《Journal of the Association of Official Analytical Chemists》1985,68(3):477-479
A sensitive, reproducible method that uses an Extrelut QE column and liquid chromatography (LC) in the reverse phase mode is described for the determination of 2-(2-quinolinyl)-1H-indene-1,3-[2H]-dione and other organic-soluble matter found in D&C Yellow No. 10. With this method the organic-soluble matter is extracted from D&C Yellow No. 10 on an Extrelut QE column, and the extract is concentrated and analyzed by LC. Recoveries averaged 104% for 2-(2-quinolinyl)-1H-indene-1,3-[2H]-dione added to purified D&C Yellow No. 10 at levels ranging from 0.50 to 5.96 ppm. 相似文献
32.
33.
Ronald Queck Anne Bienert Hans-Gerd Maas Stefan Harmansa Valeri Goldberg Christian Bernhofer 《European Journal of Forest Research》2012,131(1):165-176
Applications of flow models to tall plant canopies are limited, amongst other factors, by the lack of detailed information
on vegetation structure. A method is presented to record 3D vegetation structure and make this information applicable to the
derivation of turbulence parameters suitable for flow models. The relationship between wind speed, drag coefficient (C
D
) and plant area density (PAD) was experimentally investigated in a mixed conifer forest in the lower part of the Eastern
Ore Mountains. Essential information was gathered by collecting multi-level high-frequency wind velocity measurements and
a dense 3D representation of the forest was obtained from terrestrial laser scanner data. Wind speed dependence or streamlining
was observed for most of the wind directions. Edge effects, i.e. the influence of the here not regarded pressure gradient
and the advective terms of the momentum equation, are assumed to cause this heterogeneity. Contrary to the hypothetic shelter
effect, which would reduce the drag on sheltered plant parts, the calculated profiles of drag coefficients revealed an increasing
C
D
with PAD (i.e. a dependence on canopy and plant structure). 相似文献
34.
Early pottery at 20,000 years ago in Xianrendong Cave, China 总被引:1,自引:0,他引:1
Wu X Zhang C Goldberg P Cohen D Pan Y Arpin T Bar-Yosef O 《Science (New York, N.Y.)》2012,336(6089):1696-1700
The invention of pottery introduced fundamental shifts in human subsistence practices and sociosymbolic behaviors. Here, we describe the dating of the early pottery from Xianrendong Cave, Jiangxi Province, China, and the micromorphology of the stratigraphic contexts of the pottery sherds and radiocarbon samples. The radiocarbon ages of the archaeological contexts of the earliest sherds are 20,000 to 19,000 calendar years before the present, 2000 to 3000 years older than other pottery found in East Asia and elsewhere. The occupations in the cave demonstrate that pottery was produced by mobile foragers who hunted and gathered during the Late Glacial Maximum. These vessels may have served as cooking devices. The early date shows that pottery was first made and used 10 millennia or more before the emergence of agriculture. 相似文献
35.
Lowe JE Husmann R Firkins LD Zuckermann FA Goldberg TL 《Journal of the American Veterinary Medical Association》2005,226(10):1707-1711
OBJECTIVE: To determine whether cell-mediated immunity against porcine reproductive and respiratory syndrome (PRRS) virus is correlated with protection against reproductive failure in sows during clinical outbreaks of PRRS in commercial herds. DESIGN: Outbreak investigation in 4 swine breeding herds. ANIMALS: 97 sows. PROCEDURES: On each farm, blood samples were collected from sows with clinical signs (abortion or increased fetal death; case sows) and from clinically normal sows (control sows). The intensity of the cell-mediated immune (CMI) response was determined by use of an interferon-gamma enzyme-linked immunospot (ELISPOT) assay. Multiple logistic regression analyses and t tests were used to compare ELISPOT assay values between case and control sows. Multiple linear regression was used to investigate associations between cell-mediated immunity and the magnitude of clinical signs. RESULTS: In 2 farms, case sows had lower ELISPOT assay values than control sows. A negative association between the intensity of the CMI response and the number of pigs born dead per litter was detected on 1 farm. In 1 farm, no association was detected between the intensity of the CMI response and protection against reproductive failure. CONCLUSIONS AND CLINICAL RELEVANCE: Evidence that a strong CMI response was correlated with protection against clinical PRRS was detected in 3 of 4 farms. However, farms and sows within farms varied considerably in their immune responsiveness and in the degree to which they were protected clinically. Increasing cell-mediated immunity within infected herds has the potential to decrease clinical reproductive disease, but only if the sources of intra- and interfarm variation in the intensity of cell-mediated immunity to PRRS virus can be identified. 相似文献
36.
The use of analgesics in post‐operative adhesion (POA) research is problematic due to POA‐inhibiting effects of anti‐inflammatory agents and bowel motility‐inhibiting effects of opioids, which may increase adhesion formation. This study was conducted to assess a buprenorphine (BUP) protocol for analgesic efficacy and its effects on POA formation in a rat cecal abrasion model. The protocol was approved by the University of Florida's Institutional Animal Care and Use Committee (IACUC). Forty‐one female Sprague‐Dawley rats were randomized into two groups (n = 20 or 21 group). Body weight, food and water intake were recorded daily from 2 days before until 7 days after surgery. Treatment rats received 0.05 mg kg–1 BUP SQ at anesthesia induction and 0.3 mg kg–1 BUP orally in flavored gelatin 6 hours after surgery. Control rats received saline placebo injection and plain gelatin. All rats underwent laparotomy and controlled cecal abrasion. At 3, 6 and 24 hours post‐operatively rats were individually observed in 10‐minutes periods for pain related behavior incidence: ‘twitch’ (contraction of muscles along dorsum and/or head), ‘back arch’ (cat‐like position with front legs extended and pushing backward), ‘writhe’ (flank contraction), and ‘stagger/fall’ (momentary loss of balance while grooming or ambulating), using the method of Roughan and Flecknell (Pain 2001,90, 65–74). On post‐op day seven rats were euthanized by CO2 inhalation and POA evaluated (0 to 4 scale; ³Grade 2 = clinically significant.) BUP treated rats had lower mean pain scores than control rats at 3 hours (1.6 ± 1.7 versus 20.3 ± 13.5 (mean ± SD); p < 0.001) and 6 hours (2.1 ± 2.7 versus 23.7 ± 12.9; p < 0.001) but not 24 hours (1.5 ± 1.3 versus 4.9 ± 6.6; p = 0.35) post‐operatively. Predominant pain behavior was ‘writhe’ (flank contraction) in contrast to ‘twitch,’‘back arch,’ and ‘stagger/fall’ reported as most common pain indicators in other rat strains. BUP rats had greater mean adhesion incidence (2.4 ± 1.7 versus 1.4 ± 1.8; p < 0.03) and severity (90%³Gr.2 versus 65% of controls; p < 0.05). The BUP protocol appeared to provide effective analgesia for at least 24 hours post‐operatively. Strain of rat may affect pain related behavior. BUP should be used with caution after abdominal surgical procedures having high risk of POA formation. 相似文献
37.
D M Goldberg B Hoffman J Yang G J Soleas 《Journal of agricultural and food chemistry》1999,47(10):3978-3985
The concentrations of 11 phenols and 5 furans were measured in 12 categories of distilled spirits by HPLC methodology, together with the total antioxidant status (TAS) of the same beverages. Ellagic acid was the phenol present in highest concentration in all beverages. Moderate amounts of syringaldehyde, syringic acid, and gallic acid, as well as lesser amounts of vanillin and vanillic acid, were measurable in most samples of whiskey, brandy, and rum but were largely undetectable in gin, vodka, liqueurs, and miscellaneous spirits. 5-(Hydroxymethyl)furfural was the predominant furan in the former three beverages, notably cognac, with 2-furaldehyde the next highest, but these were undetectable in most of the latter beverages. Highest TAS values were given by armagnac, cognac, and bourbon whiskey, all three of which tended toward the highest concentrations of phenols. Negative TAS values were exhibited by rum, vodka, gin, and miscellaneous spirits in line with the low or undetectable phenol concentrations in these beverages. Wood aging is the most likely source of phenols and furans in distilled spirits. Those beverages exposed to this treatment contain significant antioxidant activity, which is between the ranges for white and red wines, with the potential to augment the antiatherosclerotic functions attributable to the ethanol that they contain. 相似文献
38.
39.
Noniodinated subunits of thyroglobulin can aggregate, but iodination of the aggregate is required for its stabilization (maturation). Rat-thyroid slices incorporate amino acids into subunits, but cannot form mature thyroglobulin from the newly synthesized subunits. This defect leads to an accumulation of 16S and 12S proteins, although the preexisting thyroglobulin is 19S. Accumulation of 16S and 12S proteins can be produced in rat thyroids by the administration to the animals of a thiocarbamide derivative, methimazole. Upon withdrawal of methimazole, iodination of the 16S and 12S proteins proceeds, and 19S protein appears. 相似文献
40.
Climate Change During the Last Deglaciation in Antarctica 总被引:1,自引:0,他引:1
PA Mayewski MS Twickler SI Whitlow LD Meeker Q Yang J Thomas K Kreutz PM Grootes DL Morse EJ Steig ED Waddington ES Saltzman P Whung KC Taylor 《Science (New York, N.Y.)》1996,272(5268):1636-1638
Greenland ice core records provide clear evidence of rapid changes in climate in a variety of climate indicators. In this work, rapid climate change events in the Northern and Southern hemispheres are compared on the basis of an examination of changes in atmospheric circulation developed from two ice cores. High-resolution glaciochemical series, covering the period 10,000 to 16,000 years ago, from a central Greenland ice core and a new site in east Antarctica display similar variability. These findings suggest that rapid climate change events occur more frequently in Antarctica than previously demonstrated. 相似文献