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21.
Using intumescent coatings on wood-based materials is an effective method for fire safety. Previous studies have demonstrated that the formulation of components strongly influences the performance of coatings. This study investigated the effect of intumescent formulation of vinyl acetate-acrylic coating on flame retardancy of plywood. The fire retardancy of materials was assessed by both heat release and CO and CO2 emissions. The CO and CO2 emissions have not been used frequently to rank materials; the highly toxic CO and CO2 may cause most fire fatalities. The fire retardancy of coatings on plywood was assessed by a cone calorimeter. Total heat release and time to peak heat release rate were the two primary parameters. The data show that low contents of binder resin (BR) and foam producing substance (FPS) decreased total heat release and lengthened time to peak heat release rate. Additionally, low BR and FPS content can form an ideal char layer. The ideal char layer significantly decreased the CO and CO2 emission. The mechanism to achieve better fire performance was verified by thermogravimetrical analysis exhibiting lower weight loss. Moreover, evaluated by 31P NMR, the low BR and FPS content can extend the survival duration of phosphor-carbonaceous chars. The results provide information for designing vinyl acetate-acrylic emulsion coating.  相似文献   
22.
Taiwania (Taiwania cryptomerioides Hay) is an important timber species in Taiwan. Growth in generally improved trees under intense silvicultural practice is so rapid that rotations or the practice of thinning trees may be as short as 20–30 years. Thus, the wood properties of young plantation trees need to be characterized to effectively use this resource. The effects of different thinning and pruning methods on the compressive strength parallel to grain of young Taiwania trees were explored. Average compressive strengths with various thinning treatments revealed the trend of no thinning > medium thinning > heavy thinning and in the pruning treatments showed the trend of medium pruning > no pruning > heavy pruning. However, most results showed no statistically significant differences among thinning and pruning treatments.  相似文献   
23.
Apoptosis, the main type of programmed cell death, plays an essential role in a variety of biological events. Whereas "classical" apoptosis is dependent on caspase activation, caspase-independent death is increasingly recognized as an alternative pathway. To develop new anticancer agents, oleifolioside A was isolated from Dendropanax morbifera Leveille and the biochemical mechanisms of oleifolioside A-induced apoptosis in HeLa cells were investigated. Exposure to oleifolioside A resulted in caspase activation and typical features of apoptosis, although cell death was not prevented by caspase inhibition. Oleifolioside A treatment induced up-regulation of Bad, loss of mitochondrial membrane potential, nuclear relocation of mitochondrial factors, apoptosis-inducing factor (AIF), endonuclease G (EndoG), and apoptosis induction. This is the first report of anticancer activity of oleifolioside A, and nuclear translocation of AIF and EndoG in oleifolioside A-treated HeLa cells might represent an alternative death signaling pathway in the absence of caspase activity.  相似文献   
24.
25.
Detailed cost-return of freshwater prawn farming in Hawaii is estimated for farms ranging in size from a minimum of 1 acre to a maximum of 100 acres. Major factors affecting cost and revenue are discussed. Freshwater prawn farming in Hawaii is profitable at the existing average annual production of 3 000 pounds/acre and at the existing average farm price of $3.00/pound for farms that are 10 acres or larger. Smaller farms are profitable only when operated as a family venture.  相似文献   
26.
Interleukin (IL)-8-encoding regions of five avian species were cloned, sequenced and characterized. Each IL-8-encoding region is 312 nucleotides long and encodes IL-8 which is 103 amino acids. Pairwise sequence analysis showed that sequence identities of IL-8-encoding regions ranged from 87% to 100%. The IL-8 protein identities varied from 84% to 100%. Phylogenetic analysis indicated that IL-8-encoding regions and encoded proteins of chicken, duck, goose and turkey clustered together and evolved into a distinct phylogenetic lineage from that of pigeon which evolved into a second lineage. The results from binding reactivities of antiserum against each recombinant IL-8 (rIL-8) protein to homologous or heterologous rIL-8 proteins, chemotactic activities of each rIL-8 protein or reduction levels of the chemotactic activity of rIL-8 protein which was pretreated with homologous or heterlogous antiserum have suggested that all five IL-8 proteins were functionally active, and shared structural and functional identity with each other.  相似文献   
27.
Neutral oxygen in the saturnian system shows variability, and the total number of oxygen atoms peaks at 4 x 10(34). Saturn's aurora brightens in response to solar-wind forcing, and the auroral spectrum resembles Jupiter's. Phoebe's surface shows variable water-ice content, and the data indicate it originated in the outer solar system. Saturn's rings also show variable water abundance, with the purest ice in the outermost A ring. This radial variation is consistent with initially pure water ice bombarded by meteors, but smaller radial structures may indicate collisional transport and recent renewal events in the past 10(7) to 10(8) years.  相似文献   
28.
Sixty Actinobacillus pleuropneumoniae (App) strains from pigs in Taiwan were examined. Serotyping revealed that these belonged to serovars 1 (n=53), 2 (n=3), and 5 (n=4). Agar disk diffusion susceptibility testing of the isolates showed 55 (92%) were resistant to three or more antimicrobial agents. Six resistance patterns were observed. Ampicillin-chloramphenicol-flumequine-nalidixic acid-streptomycin-sulfonamide/trimethoprim-tetracycline was the most common multi-resistance pattern. Minimal inhibitory concentration of 14 antimicrobial agents was determined. The isolates were highly susceptible to ceftiofur and trimethoprim in vitro. Isolates were resistant to streptomycin, ampicillin, and nalidixic acid. All isolates were examined for the presence of plasmids using the alkaline lysis method. Forty three (72%) isolates had four plasmid bands with an approximate sizes of 3.5, 4.3, 5.8 and 6.0 kb; 12 (20%) had three bands at 3.5, 4.3 and 5.2 kb, and 5 (8%) had no plasmid bands. Antimicrobial resistance plasmids were detected in resistant strains of App. Three antimicrobial resistance plasmids were transformed into E. coli DH5 alpha. pTMY1 (4.3 kb) encoded a streptomycin kinase and a dihydropteroate synthase; pTMY2 (6.0 kb) encoded ROB-1 beta-lactamase and aminoglycoside 3'-phosphotransferase; pTMY3 (5.2 kb) encoded only ROB-1 beta-lactamase. The 4.3 kb plasmid was sequenced and consisted of 4242 bp with 42.9% GC content. The 4.3 kb plasmid DNA sequence was 98% homologous to a plasmid previously isolated from Pasteurella haemolytica.  相似文献   
29.
Borrelia burgdorferi, the etiologic agent of Lyme disease is a tick born spirochetal infection. Clinical signs of Lyme borreliosis are uncommon in horses, but when present they are often vague and nonspecific. In horses, Lyme borreliosis has been implicated in musculoskeletal, neurological, reproductive, and ocular disorders, including uveitis, but definitive diagnosis can be challenging as the causative agent is rarely isolated and serologic tests can be unreliable and do not confirm active disease. Here, we report two cases of equine uveitis associated with B. burgdorferi based on the identification of spirochetes within ocular fluids and confirmed with PCR testing. The two cases illustrate some of the challenges encountered in the recognition and diagnosis of equine Lyme borreliosis. Although only one of many possible causes of equine uveitis, Lyme disease should be considered a differential diagnosis, especially in endemic areas. Given the possibility for false negative results of serum tests during uveitis associated with B. burgdorferi and the failure of such tests to confirm active infection, a combination of cytologic assessment, antibody, and/or PCR testing of ocular fluids may be worthwhile if the clinical suspicion for Lyme uveitis is high.  相似文献   
30.
The water deer (Hydropotes inermis) has conventionally been classified into two subspecies according to geographic distribution and pelage color pattern: H. i. inermis from China and H. i. argyropus from Korea. However, the results of a recent molecular study have called this into question. To further reappraise this classification, we examined morphological variation in craniodental measurements of these 2 subspecies. Results of univariate and multivariate analyses demonstrated that these 2 subspecies are not well-differentiated, suggesting that individuals of the 2 populations share common morphological traits. Despite the distribution of the subspecies at different latitudes, no clear morphocline was detected, suggesting that Bergmann’s rule does not apply in this case. Discriminant analysis indicated that the characteristics of individuals are shared by both populations, suggesting that not all individuals can be assigned to their original population. Results of principal component analysis showed that the two populations shared more than 75% of individuals, congruent with the “75% rule” of subspecies classification. In both the neighbor-joining and unweighted pair group methods with arithmetic mean cluster analyses, specimens of H. i. argyropus and H. i. inermis were highly mixed within the cladograms. These results suggest that the overall morphological variation in the 2 subspecies overlaps considerably and that there is no coherent craniofacial difference between the 2 groups. The present findings combined with prior observations from molecular biogeography point out that the taxonomic division of water deer into 2 subspecies should be revisited.  相似文献   
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