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91.
Blueberry fruit growth commonly exhibits a double-sigmoid pattern. The goal of this work was to characterize and compare fruit growth of cultivars differing in ripening time using exponential non-linear mixed models. Mixed-effects five-parameter exponential (Gompertz I and II; logistic; monomolecular) models were fitted to fruit diameter data from 2 years and three cultivars grown in the field in a cool temperate environment. Gompertz II mixed model provided the best fit to fruit growth data and was used for further analysis. In later ripening cultivars ‘Cape Fear’ and ‘Herbert’, clear-cut double-sigmoid patterns were observed, absolute growth rate models exhibited two marked peaks, and relative growth rate showed an initial decreasing trend, and a subsequent peak. The earlier cv. ‘O’Neal’ did not exhibit a defined double-sigmoid pattern. The time between relative extremes of absolute growth acceleration is proposed as an objective criterion for fixing stage boundaries within growth curves. Exponential mixed models accurately fitted blueberry growth patterns. These equations highlighted differences in fruit growth patterns between early and late ripening highbush blueberry cultivars.  相似文献   
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The only known case of an avian digestive system with active foregut fermentation is reported for the hoatzin (Opisthocomus hoazin), one of the world's few obligate folivorous (leaf-eating) birds. Hoatzins are one of the smallest endotherms with this form of digestion. Foregut fermentation in a flying bird may be explained by increased digestive efficiency by selection of highly fermentable and extremely patchy resources, coupled with microbial nutritional products and secondary compound detoxification. This unexpected digestive system gives a new perspective to the understanding of size limitations of vertebrate herbivores and to the evolution of foregut fermentation.  相似文献   
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The effect of bacteria represented by indigenous soil microflora or a mixture of soil bacteria Pseudomonas aeruginosa and Rhodococcus erythropolis on fungal growth, extracellular enzyme production and polycyclic aromatic hydrocarbons (PAHs) biodegradation efficiency in soil of white-rot fungi Trametes versicolor and Irpex lacteus was investigated. Both fungi were able to colonize soil. The growth yields measured by ergosterol were about two-fold in I. lacteus after 10 weeks. Laccase was produced in T. versicolor cultures in the presence or absence of bacteria but live bacteria reduced the laccase levels in soil about 5 times. Manganese-dependent peroxidase (MnP) was not detected in T. versicolor cultures. The amounts of MnP and laccase in I. lacteus cultures were not affected by the presence of bacteria. T. versicolor was more efficient in PAH removal for all PAHs tested although its capacity to colonize soil was lower. The removal rates of PAHs by T. versicolor in sterile soil were 1.5-fold, 5.8-fold and 1.8-fold for 2-3-ring, 4-ring and 5-6-ring PAHs, compared to I. lacteus, respectively. I. lacteus showed a low efficiency of removal of pyrene, benzo[a]anthracene and benzo[k]fluoranthene, compared to T. versicolor, whereas chrysene and benzo[b]fluoranthene were degraded by neither fungus. The main effect of the presence of the indigenous microflora or R. erythropolis and P. aeruginosa was a significant decrease of degradation of total PAHs by both T. versicolor and I. lacteus. Weak fungal/bacterial synergistic effects were observed in the case of removal of acenapthylene, benzo[a]pyrene, dibenzo[a,h]anthracene and benzo[g,h,i]perylene by I. lacteus and acenapthylene by T. versicolor. However, the bacterial effects were different in the two fungi. PAH abiotic losses represented 15 and 21% of the total PAHs after 5 and 10 weeks, respectively; naphthalene and acenaphthene were removed from the soil due to volatilization.  相似文献   
97.
The effect of growth promotants (bacitracin, virginiamycin, and flavomycin) on the genetic population of Enterococcusfaecium isolated from a commercially integrated poultry farm was examined. A total of 551 E. faecium were isolated from chick boxliners (n=16), litter (n=334), feed (n=67), and carcass rinse (n=134) samples from four chicken houses. Two houses on the farm were control houses and did not use any antimicrobials while two other houses on the farm used flavomycin, virginiamycin, and bacitracin during six different chicken grow outs. BOX-PCR and pulsed-field gel electrophoresis (PFGE) results indicated that E. faecium strains had a high degree of genetic diversity as overall clustering was independent of source, house, or grow out. Similarity of > or =60% for the majority of BOX-PCR genogroups and > or =80% for the majority of PFGE genogroups was observed for a subset of carcass rinse samples (n=45) examined. Seventy-nine percent (19/24) of isolates in BOX-PCR genogroup 2 also clustered in PFGE genogroup 2, although no association between the isolates and house or grow out was observed. These results suggest that E. faecium from chicken are genetically diverse and that growth-promoting antimicrobials do not affect the genetic population of E. faecium.  相似文献   
98.
Microsporum canis has been frequently isolated from human cases of tinea capitis and tinea corporis. The infection may be acquired from infected animals with cutaneous lesions but also from asymptomatic carriers or from the environment. As asymptomatic M. canis carriers are considered to be a critical factor in the epidemiology of dermatophytosis in humans, this study investigated the relationship between the presence of dermatophytes on the hair coats of dogs and cats without cutaneous lesions and the occurrence of the disease in their respective owners. A total of 136 dogs and 248 cats were sampled from January 1999 to January 2005. Seventy-eight animals (22 dogs and 56 cats) belonged to individuals affected by tinea corporis caused by M. canis and 306 (114 dogs and 192 cats) to individuals without dermatophytosis. Age, sex, breed, habitat and season were recorded for each animal and examined as potential risk factors. Dermatophytes were isolated from 20.5% of the dogs and 28.2% of the cats. Microsporum canis was isolated from 36.4% of dogs cohabiting with owners diagnosed with tinea corporis but it was never isolated from dogs whose owners had no lesions. By contrast, M. canis was isolated from 53.6% of cats cohabiting with owners diagnosed with tinea corporis and from 14.6% of cats whose owners had no signs of the disease. These results clearly indicate that both cats and dogs should be considered as a major source of pathogenic dermatophytes for humans even when they do not present clinical signs of dermatophytosis.  相似文献   
99.
Cystic echinococcosis is the most prevalent zoonosis in Tierra del Fuego province, Argentina, with important economic, productive and public health consequences. The present work was performed to determine the ovine prevalence in Tierra del Fuego, Argentina, as well as to evaluate the quality of diagnostic systems in slaughterhouses. Moreover, genetic analyses to characterize the strain of Echinococcus granulosus involved in the region were done. The first actions to perform a diagnosis of the epidemiological situation of hydatidosis in Tierra del Fuego were done between 1976 and 1977. A canine prevalence of 80% and an ovine prevalence of 55% results were obtained. Since 1979 the control program of Hydatidosis of Tierra del Fuego was implemented. It was based on semiannual canine anthelmintic treatment with praziquantel at dose of 5mg/kg, and complemented with sanitary education and canine and ovine epidemiological surveillance. During May 1997-January 1999: 5,916 sheep coming from 20 farms of the programmatic area were evaluated. In the lamb category, hydatid cysts were not found. In the adults category, 62 infected animals were found (3.2%). The ovine prevalence was 1.1% and there was 100% of coincidence between diagnosis in the slaughterhouse, re-inspection in the laboratory and histopathological study. The marked decrease in the prevalence observed for sheep infection evidenced a destabilization of the biological cycle of the parasite. This could be explained by the application of a control program with uninterrupted systematic actions. Polymerase chain reaction-ribosomal ITS-1 DNA (rDNA) restriction fragment length polymorphism (PCR-RFLP) analysis and partial sequencing of the mitochondrial cytochrome c oxidase subunit 1 (CO1) gene were used to characterize E. granulosus isolates collected from different regions of Tierra del Fuego to determine which genotypes occurred in this region. The results revealed the presence of the G1 genotype (sheep-dog strain). This is the first time that a molecular analysis was performed for the E. granulosus isolates from Tierra del Fuego.  相似文献   
100.
The vacuum distillation of bergamot peels furnishes a high-quality essential oil that is totally bergapten-free. This oil was compared with that produced by distillation of cold-pressed oils and those commercially available. The oil obtained by vacuum distillation of the bergamot vegetable matrix shows a composition quite similar to that of the cold-pressed oil. It also displays qualitative characteristics that are superior with respect to those normally observed for essential oils isolated by distillation of cold-pressed oils. Oils isolated by the method presented here can constitute ideal candidates in producing foods, for example, Earl Grey tea, and cosmetic preparations.  相似文献   
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