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991.
Lim TH Lee DH Lee YN Park JK Youn HN Kim MS Lee HJ Yang SY Cho YW Lee JB Park SY Choi IS Song CS 《Avian diseases》2011,55(3):435-438
A Salmonella Gallinarum (SG)-specific bacteriophage isolated from sewage effluent was used to prevent horizontal transmission of SG in commercial layer chickens. Six-week-old chickens, each challenged with 5 x 10(8) colony-forming units of SG, cohabited with contact chickens treated with 10(6) plaque-forming units/kg of bacteriophage, prepared in feed additives, for 7 days before, and 21 days after challenge with SG. Mortality was observed for 3 wk after challenge and SG was periodically reisolated from the liver, spleen, and cecum of chickens. SG re-isolation from organs was decreased and a significant (P < 0.05) reduction in mortality was observed in contact chickens treated with the bacteriophage, as compared to untreated contact chickens, indicating that bacteriophage administration in feed additives significantly prevented the horizontal transmission of SG. These results provide important insights into prevention and control strategies against SG infection and suggest that the use of bacteriophages may be a novel, safe, and effectively plausible alternative to antibiotics for the prevention of SG infection in poultry. 相似文献
992.
Microbial conversions of unsaturated fatty acids often generate polyhydroxy fatty acids, giving them new properties such as higher viscosity and reactivity. A bacterial strain Pseudomonas aeruginosa (PR3) has been intensively studied to produce mono-, di-, and trihydroxy fatty acids from different 9-cis-monoenoic fatty acids such as oleic acid, ricinoleic acid, and palmitoleic acid. However, from the results and the postulated similar metabolic pathways involved in these transformations, it was assumed that the enzyme system involved in transformation of the monoenoic fatty acid by strain PR3 could utilize fatty acids with different chain lengths and locations of the double bond. In this study was used as a substrate for bioconversion by strain PR3 eicosenoic acid (C20:1, ω-9) containing a singular cis double bond at different positions from the carboxyl end as oleic acid, and it was confirmed that PR3 could produce a novel 9,12-dihydroxy-10(E)-eicosenoic acid (DED) with 6.2% yield from eicosenoic acid. The structure of DED was confirmed using GC-MS, FTIR, and NMR analyses. DED production was maximized at 72 h after the substrate was added to the 24 h culture. Some other nutritional factors were also studied for optimal production of DED. 相似文献
993.
Doria F. C. Borges A. C. Kim J. K. Nathan A. Joo J. C. Campos L. C. 《Water, air, and soil pollution》2013,224(2):1-9
In this study, we have reported the synthesis of new amino-substituted p-tert-butylcalix[4]arene (3) and its application for the removal of two carcinogenic azo dyes, i.e., Chicago Sky Blue (CSB) and Tropaeolin 000 (TP) from aqueous environment. The newly synthesized calix–ligand 3 is characterized by FT-IR and 1H NMR spectroscopy as well as elemental analysis. The extraction efficiency of newly calix–ligand 3 for CSB and TP dyes from aqueous media was evaluated through liquid–liquid extraction experiments. The newly synthesized calix–ligand 3 showed outstanding extraction percentage and maximum percent extraction, i.e., 97 and 96 % of CSB and TP dyes was achieved at pH 9, respectively. During the extraction process, effect of various parameters was monitored and found that extraction is highly dependent on pH and salinity. Moreover, cyclic structure, cavity size, functional groups of the calixarene derivative, hydrophobicity, and the ionic property of guest molecules also affect the extraction efficiency. The comparative data prop up calix–ligand 3 as an effective extractant for both CSB and TP dyes. 相似文献
994.
The sprout inhibitor chlorpropham (CIPC) was applied in varying concentrations to individual eyes of potato tubers. Sensitivity of a given eye to CIPC depended upon the status of the remaining eyes on the same tuber. If the remaining eyes were inhibited, higher concentrations of CIPC were required for inhibition of the given eye. Apical eyes were more sensitive to CIPC than were lateral eyes. It was confirmed that CIPC is highly volatile and that contaminating levels of CIPC vapors can induce a rosette sprout growth. Seed potatoes treated with low concentrations of CIPC before planting sprouted more slowly than untreated potatoes, and the delay was related to CIPC concentration. At high CIPC levels, total emergence as well as rate of emergence was reduced. However, emergence was far greater than would have been anticipated from the sprouting of similar treated lots held in storage. 相似文献
995.
Conjoint analysis is a method for measuring and modeling consumer preferences for multiattribute alternatives. The purpose
of this research was to determine the preferred high-performance fabrics for a mountaineering jacket to identify those fabric
attributes best suited to the consumer’s needs. A conjoint analysis was conducted using 120 samples taken from mountaineering
club members including university students and amateur hikers, who ranked their preferences in the selection of a hypothetical
jacket based on the profiles derived from an orthogonal design. Our results show that the water/windproof attribute was the
most important in choosing a hypothetical jacket (27.6 %), followed by price (24.9 %), breathability (24.8 %), durability
(18.1 %), and weight (4.6 %). 相似文献
996.
Water interactions in polycarbonate films have been studied using fluorescence and NIR Fourier transform spectroscopy. During
water sorption process, the fluorescence emission spectra showed sensitive changes with the peak at 332 nm red shifted by
18 nm with water sorption. This red-shifted peak could be due to phenyl-2-phenoxybezoate, which is one of two major thermal
degradation products in polycarbonate. In the spectra of phenyl-2-phenoxybenzoate in dimethyl formamide solution, a progressive
red shift was also observed with the water addition. By using the NIR spectra, hydrogen-bonding interactions of the sorbed
water with polycarbonate were investigated. It was found that water can be analyzed as free water S0 or single hydrogen bonded water, S1 while double hydrogen bonded water was negligible. During water immersion, most water species which are present as S0 species decrease slightly, with a small increase in S1 species. During desorption, S0 species decrease sharply, while S1 species is reduced gradually. Two examples of S1 structure in water-sorbed polycarbonate are proposed. 相似文献
997.
Assessment of the water quality of two rivers in Hanoi City and its suitability for irrigation water
Nguyen Thi Lan Huong Masami Ohtsubo Loretta Li Takahiro Higashi Motohei Kanayama 《Paddy and Water Environment》2008,6(3):257-262
The To Lich and Kim Nguu Rivers in Hanoi City are the main sources of irrigation water for suburban agricultural land and
fish farm. Wastewater from the industrial plants located along these rivers has been discharged, and has degraded the water
quality of the rivers. This study describes the chemical properties of water from the rivers, focusing on heavy metal pollution
and the suitability of water quality for irrigation water. Water from the rivers was heavily polluted with organic matter
and heavy metals such as Pb, Cu, Zn, Cr, Cd and Ni. Dissolved oxygen, chemical oxygen deman, and total suspended solids, and
the concentrations of all heavy metals exceeded the Vietnamese standard for surface water quality in all investigated sites.
The concentrations of some heavy metals such as Cu, Cd, Cr and Ni were above the internationally recommended WHO maximum level
for irrigation water. A wide variation in the heavy metal concentration of water due to metal types is the result of wastewater
discharged from different industrial sources. 相似文献
998.
Xiaochuan Li Young-Sung Kim Sung-Hoon Kim Kun Jun Young-A Son 《Fibers and Polymers》2009,10(6):739-742
In this contribution, three triphenylamine derivatives were synthesized and their spectral properties were investigated. Knoevenagel
condensation of mono-, di-, and tri-aldehydes of triphenylamine with 1,3-indanedione yields D-π-A type dyes with push-pull
chromophores. The absorption and luminescence properties of the dyes were discussed in terms of their electronic structures.
The results of molecular orbital computer simulations, based on Material Studio, were found to provide a reasonable explanation
for the observed spectral properties related to the push-pull features causing dramatic changes in UV-Vis absorption as well
as in photoluminescence. 相似文献
999.
Erwinia pyrifoliae, an Erwinia species different from Erwinia amylovora, causes a necrotic disease of Asian pear trees 总被引:3,自引:0,他引:3
Bacteria from necrotic branches of Asian pear trees ( Pyrus pyrifolia ) in Korea were consistently isolated as white colonies on nutrient agar and formed mucoid, slightly yellow colonies on a minimal medium with copper sulphate. Isolates with this colony morphology were studied in a series of microbiological, molecular and pathological tests. Most isolates allowed the verification of Koch's postulate on P. pyrifolia seedlings and on slices from immature pear ( Pyrus communis ) fruits and were also positive in hypersensitivity tests on tobacco leaves. They showed characteristics common to species in the genus Erwinia , but were different from Erwinia amylovora , the agent of fire blight. A relationship between the novel pathogen and E. amylovora was found in microbiological and serological tests. Both organisms had similar but not identical protein patterns in 2-D gel electrophoresis, and in growth morphology the new pathogen produced colonies on MM2 Cu medium that were mucoid and slightly yellow, compared with the clearly yellow colonies of E. amylovora . No similarity was found in the plasmid profiles, and consequently no PCR signal was obtained with primers from the E. amylovora plasmid pEA29. REP-PCR also produced bands differing for the two organisms. 相似文献
1000.
Lulu Cheng Inyoung Kim Herbert Pang 《Journal of Agricultural, Biological & Environmental Statistics》2016,21(4):641-662
In this paper, we propose a semiparametric regression approach for identifying pathways related to zero-inflated clinical outcomes, where a pathway is a gene set derived from prior biological knowledge. Our approach is developed by using a Bayesian hierarchical framework. We model the pathway effect nonparametrically into a zero-inflated Poisson hierarchical regression model with an unknown link function. Nonparametric pathway effect was estimated via a kernel machine, and the unknown link function was estimated by transforming a mixture of the beta cumulative density function. Our approach provides flexible nonparametric settings to describe the complicated association between gene expressions and zero-inflated clinical outcomes. The Metropolis-within-Gibbs sampling algorithm and Bayes factor were adopted to make statistical inferences. Our simulation results support that our semiparametric approach is more accurate and flexible than zero-inflated Poisson regression with the canonical link function, which is especially true when the number of genes is large. The usefulness of our approach is demonstrated through its applications to the Canine data set from Enerson et al. (Toxicol Pathol 34:27–32, 2006). Our approach can also be applied to other settings where a large number of highly correlated predictors are present.Supplementary materials accompanying this paper appear on-line. 相似文献