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51.
Current study investigated the fermentative production of cell mass and crude protein using an axenic culture of the thermotolerant strain of Chlorella vulgaris grown mixotrophically in an illuminated 10-l glass bioreactor. The process was then upscaled to 1,000-l bioreactor. The organism supported maximum specific growth rate, crude protein volumetric productivity, and specific productivity of 1.2?day?1, 2.26?g?l?1?day?1, and 0.76?g?g?1?day?1, respectively, with urea as nitrogen source. Gibbs free energy, enthalpy, and entropy values for its formation were 74.3, 56. 2?kJ?mol?1, and ?59.1?J?mol?1?K?1, respectively, in both reactors and corresponded to those of thermotolerant organisms. Algal biomass grown in 10-l bioreactor contained 0.52?±?0.03, 12.6?±?2.0, 60.0?±?4.5, 0.4?±?0.02, 4.5?±?0.2, 12?±?0.5, and 3.81?±?0.5% carotenoids, carbohydrates, crude protein, DNA, RNA, lipids, and total chlorophyll, respectively. Dry biomass supported good growth of fish larvae comparable with that on commercial diet.  相似文献   
52.

In South Asia, an increasing population and frequent droughts have been significant factors deeply affecting water deficits in the region. In this study, recent drought conditions were evaluated by calculating the standardized precipitation index (SPI) for the period of 1991–2006, based on past data during the period from 1961 to 1990. In addition, the Thornthwaite equation was used to compute monthly potential evapotranspiration for the entire area of Indonesia. The APHRODITE data set was utilized for precipitation and temperature. Monthly rainfall data from April to September for 30 years (1961–1990) were used to obtain the gamma function for the computation of SPI values. Calculated probability of SPI for which values were < − 2 during the period from 1991 to 2006 was used to evaluate recent Indonesian drought conditions. Regarding potential soil water deficits, under the very simple assumption that the root zone is 30 cm, soil porosity is 0.4, and field capacity is 80% of soil porosity, the critical threshold of soil water deficit was set as − 96 mm. Frequency of potential water deficits < − 96 mm was counted during 1991–2006. The results of the SPI in Indonesia indicate that most parts of Indonesia have encountered severe and extreme drought for the period 1991–2006. Based on SPI interpretation, Borneo Island and West Papua are the islands that encountered the most extreme drought during the dry seasons. Borneo Island seems to have encountered extreme drought at the beginning and the middle of the dry seasons (April, May, and July). On the other hand, based on the Thornthwaite interpretation, Java and Bali Islands, and especially in Central Java and East Java, seem to have encountered the greatest soil water deficit at the middle and the end of the dry seasons (May, June, July, and September).

  相似文献   
53.
Free range indigenous chickens suffer from low productivity due to inadequate quantity and quality of feed, high predation and high mortality rates. The aim of the study was to establish the nutritional gaps in the free range chickens’ diets. A total of 40 farmers from two locations participated in the study. The study used 548 chickens aged 7–8 months purchased from farmers. The experimental chickens were slaughtered before weighing the carcass and crop content. The weight of the gastro-intestinal tract, heart and liver was also recorded. The crop contents were analysed after drying in the oven for 48 hours at 60 °C to determine what was consumed. The mean live weight of the experimental chickens was 1443 ± 296?g. The chickens mainly fed on maize, which accounted for over 80% of their diet. The estimated metabolizable energy (ME) of the crop contents for the study chickens was 2887.8 Kcal/kg. Although the chickens from Kionyweni had significantly (P<0.05) higher ME than those from Kilome, it was lower than the 3044 Kcal/kg recommended for scavenging chickens. The crude protein (CP) was 10.6 ± 2.8%, which was lower than the 16–18% CP requirement for layers. The essential amino acids available to the chickens in the two study areas included lysine, tryptophan and methionine-cysteine. Their availability was higher during the rainy season compared to the dry season.  相似文献   
54.
Six Newcastle disease virus (NDV) isolates were obtained from disease outbreaks on different poultry farms in the Sudan between 1988 and 1991. The pathogenic properties of these isolates were studied in comparison to those of strain Herts 33/56. All the isolates were similar in that they killed chicken embryos quickly, in mean death time (MDT) and embryo lethal dose 50 per cent (ELD50), had higher intracerebral pathogenicity indices (ICPI), and produced viscerotropic lesions in the infected chickens. The field isolates had the characteristics of the velogenic viscerotopic strains of NDV. The pathogenesis of infection caused by one of the isolates was studied. The virus was first detected in different organs and in oral and cloacal swabs on the third day after infection.  相似文献   
55.
Apoptosis seems to play an important role in the pathogenic profile of bovine herpesvirus 1 (BHV-1) infection. Nitric oxide (NO) is also important as a signal molecule. In this study, apoptosis was selectively induced in HEp-2 cells in the early stage [1-3 h postinfection (PI)] of BHV-1 multiplication, and this apoptotic process was realised through the caspase-8, and partially through the caspase-3, pathway. BHV-1 infection inhibited staurosporine- (SS-) induced apoptosis only if the SS was added at 6 h PI. The results of this study showed that the 'NO-apoptosis' relation was realised through the caspase-8 pathway ('outer membrane receptor' pathway) at a later stage of infection in apoptosis induced by BHV-1 + SS. Our previous report (Yazici et al., 2004) and this study together showed that BHV-1 might induce and inhibit cell-type-specific pathways of apoptosis.  相似文献   
56.
57.
This study investigated the effect of type‐I interferon (IFN) on the expression of matrix metalloproteinases (MMPs) of the bovine endometrial stromal cells (BES) and epithelial cells (BEE). The cells were separated and purified from the caruncles and cultured in DMEM/F‐12 containing 10% fetal bovine serum. Spheroids were generated by using ascorbate. Zymograms of the supernatant showed that BEE predominantly expressed MMP‐9, whereas MMP‐2 was expressed in BES and homo‐spheroids. While MMPs expression was not detected in hetero‐spheroids. Real‐time quantitative PCR revealed that type‐I IFN and P4 suppressed the gene expression of MMP‐2 and MMP‐9 in hetero‐spheroids, respectively. On the other hand, gelatin zymography analysis of the supernatant showed that type‐I IFN strongly promote the clearance of MMPs. While zymograms of the MMPs stocked in the hetero‐spheroids were significantly reduced by type‐I IFN. Phenylmethanesulfonyl fluoride and leupeptin (both are serine proteinase inhibitors) significantly repressed the clearance of MMP‐2 and MMP‐9 induced by type‐I IFN. Moreover, collagen fibers in hetero‐spheroids significantly decreased after the treatment with type‐I IFN. In conclusion, it was suggested that type‐I IFN participate in the tissue remodeling by regulation the clearance of MMPs.  相似文献   
58.
59.
In this study, Gonium sp. was investigated for possible usage in dye-containing wastewater treatment. Trials were performed in media including triacontanol hormone, Reactive Orange 14, Reactive Red 120, Reactive Black 5, Remazol Brilliant Blue R (RBBR), and also hormone against the controls. Algae could remove RBBR with the highest dye removal percentage (56%) among the tested dyes. The optimum pH was 9 in removing 50 mg L?1 RBBR at a dye removal percentage of 47.1%. The role of laccase activity of Gonium sp. was also investigated. This first attempt in the literature showed the involvement of the enzyme in the algal growth and bioremoval process. In the presence of the plant growth hormone in the culture, the activity showed a steady and significant increase up to nearly sixfold between 5th and 14th days of incubation.  相似文献   
60.
In the parasitic wasp, Nasonia vitripennis, males are haploid and usually develop from unfertilized eggs, whereas females are diploid and develop from fertilized eggs. Some individuals in this species carry a genetic element, termed psr (paternal sex ratio), which is transmitted through sperm and causes condensation and subsequent loss of paternal chromosomes in fertilized eggs, thus converting diploid females into haploid males. In this report the psr trait was shown to be caused by a supernumerary chromosome. This B chromosome contains at least three repetitive DNA sequences that do not cross-hybridize to each other or to the host genome. The psr chromosome apparently produces a trans-acting product responsible for condensation of the paternal chromosomes, but is itself insensitive to the effect. Because the psr chromosome enhances its transmission by eliminating the rest of the genome, it can be considered the most "selfish" genetic element yet described.  相似文献   
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