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The model considered in this article is the two-factor nested unbalanced variance component model: for p = 1, 2, …, P; q = 1, 2, …, Qp; and r = 1, 2, …, Rpq. The random variables Ypqr are observable. The constant μ is an unknown parameter, and Ap, Bpq and Cpqr are (unobservable) normal and independently distributed random variables with zero means and finite variances σ2A, σ2B, and σ2C, respectively. Approximate confidence intervals on ?A and ?B using unweighted means are derived, where The performance of these approximate confidence intervals are evaluated using computer simulation. The simulated results indicate that these proposed confidence intervals perform satisfactorily and can be used in applied problems.  相似文献   
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BioControl - In recent years, Fungal Biocontrol Agents (FBCAs) have played a significant role in the biological control of pests and plant pathogens of several economically important crops,...  相似文献   
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Stem cell niche research uses nanotechnologies to mimic the extra-cellular microenvironment to promote proliferation and differentiation. The aim of designing different scaffolds is to simulate the best structural and environmental pattern for extracellular matrix. This experiment was designed to study the proliferative behaviour of canine bone marrow deriver mesenchymal stem cells (MSCs) on different nanomaterial based thin film scaffolds of carbon nanotubes (CNT), chitosan and poly ε-caprolactone. Similar number of cells was seeded on the scaffolds and standard cell culture flask, taken as control. Cells were maintained on DMEM media and relative number of metabolically active cells was determined by MTT assay up to day six of culture. Cells proliferated on control and all the scaffolds as the days progressed. Although proliferation rate was slow but no decline of cell number was noticed on the scaffolds during the study period. Initially, the cell proliferation was lower on CNT but as time progressed no significant difference was observed compared to control. The result indicated that nanomaterial based scaffolds reduce the proliferation rate of canine MSCs. However, canine MSCs adapted and proliferated better on CNT substrate in vitro and may be used as a scaffold component in canine tissue engineering in future.  相似文献   
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The silkworm, Antheraea assamensis Helfer (Lepidoptera: Saturniidae), grows primarily on Persea bombycina and Litsea polyantha. To understand if the restricted diet breadth is due to the specific role of gustatory sensilla of the larvae of A. assamensis, the same fifth instar larvae retaining only labrum‐epipharynx or galeal sensilla were subjected to food choice tests. The foods used were leaves of two host‐plant and two non‐host‐plant species. Mean per cent consumption and per cent of choosing larvae were used as parameters for drawing conclusions. The finding indicated involvement of the labrum‐epipharynx for acceptance and galeal sensilla for rejection of a non‐host‐plant species. Scanning electron microscope studies revealed the presence of two sensilla on the galea, one lateral and one medial sensilla styloconicum and two gustatory sensilla in the epipharynx of A. assamensis. The study revealed the key role of galeal sensilla in the restrictive diet‐breadth of A. assamensis.  相似文献   
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In order to prove the hypothesis that humans and animals with adequate vitamin A status do not absorb and metabolize orally administered all-trans retinoyl β-glucuronide, unlabeled retinoyl glucuronide (0.1 mmol) was orally dosed to fasting well-nourished young men. Neither retinoyl glucuronide nor retinoic acid, a possible metabolite, appeared in the blood within 12 h after ingestion. Next, radiolabeled all-trans 15-[14C]-retinoyl β-glucuronide was chemically synthesized by a new procedure, and fed orally to rats of different vitamin A status. Analysis of blood and other tissues 5 or 24 h after the dose, showed the presence of radioactivity ( 0.5%) in the blood of vitamin A deficient rats, but not in sufficient rats. Livers of all rats contained small, but detectable amounts (0.3 to 1.1% of the dose) of radioactivity. The accumulation of radioactivity in the liver was highest in deficient rats. Analysis of the retinoids showed that the radioactivity in serum and liver was due to retinoic acid formed from retinoyl glucuronide. Within 24 h after the dose, 31 to 40% of the administered radioactivity was excreted in the feces, and 2 to 4.7% of the dose was excreted in the urine. Results of the present studies show that oral administration of retinoyl β-glucuronide did not give rise to detectable changes in blood retinoyl glucuronide and/or retinoic acid concentrations in humans or rats with adequate vitamin A status.  相似文献   
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Visual cues are known to be used by numerous animal taxa to gather information on quality and location of resources. The present work was carried out to understand if visual cues are involved in host localization by E. sorbillans and if so, does an associative learning influence host localization behaviour. The Uzi fly, Exorista sorbillans Widemann is an endoparasitoid of the silkworm, Antheraea assama Westwood and a serious threat to the silk production industry in general. Associative learning in the fly was studied by using green and orange coloured paper disk in presence or absence of a reward, sugar or silk worm larvae. Training for the rewards in the learning experiment was given for 2 days for 30 min at regular intervals. Flies positively associated colored paper disks with the presence of hosts which indicated that they might employ visual learning of microhabitats associated with host habitats, or the hosts themselves. Our results showed that in context of host foraging, training with colours as host associated cues was more reliable than training with colours in the absence of hosts. Thus associative learning may be considered to be an essential component for survival of Exorista sorbillans.  相似文献   
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Two species of Trentepohlia, i.e., Trentepohlia aurea and Trentepohlia cucullata were collected from walls and tree bark, respectively, at two different seasons in a year. The total carotenoid content in both the species is very high during winter but decreases significantly during summer. By spectroscopic analysis, it was found that. T. aurea and T. cucullata growing in natural habitats are rich sources of carotenoids. The individual carotenoids were separated, identified, and estimated by HPLC, and identified as β-carotene along with some other carotenoids, i.e., neoxanthin, lutein, β-cryptoxanthin, β,γ-carotene, β,ε-carotene (absent during summer).  相似文献   
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Recently, there has been a growing interest in the sparse representation of signals over learned and overcomplete dictionaries. Instead of using fixed transforms such as the wavelets and its variants, an alternative way is to train a redundant dictionary from the image itself. This paper presents a novel de-speckling scheme for medical ultrasound and speckle corrupted photographic images using the sparse representations over a learned overcomplete dictionary. It is shown that the proposed algorithm can be used effectively for the removal of speckle by combining an existing pre-processing stage before an adaptive dictionary could be learned for sparse representation. Extensive simulations are carried out to show the effectiveness of the proposed filter for the removal of speckle noise both visually and quantitatively.  相似文献   
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1. Mouse lines lacking prion protein (PrP(C)) have a puzzling phenotypic discrepancy. Some, but not all, developed late-onset ataxia due to Purkinje cell degeneration. 2. Here, we identified aberrant mRNA species in the brain of Ngsk Prnp0/0 ataxic, but not in nonataxic Zrch Prnp0/0 mouse line. These mRNAs were chimeric between the noncoding exons 1 and 2 of the PrP gene (Prnp) and the novel sequence encoding PrP-like protein (PrPLP), a putative membrane glycoprotein with 23% identity to PrP(C) in the primary amino acid structure. The chimeric mRNAs were generated from the disrupted Prnp locus of Ngsk Prnp0/0 mice lacking a part of the Prnp intron 2 and its splice acceptor signal. 3. In the brain of wild-type and Zrch Prnp0/0 mice, PrPLP mRNA was barely detectable. In contrast, in the brain of Ngsk Prnp0/0 mice, PrP/PrPLP chimeric mRNAs were expressed in neurons, at a particularly high level in hippocampus pyramidal cells and Purkinje cells under the control of the Prnp promoter. 4. In addition to the functional loss of PrP(C), ectopic PrPLP expression from the chimeric mRNAs could also be involved in the Purkinje cell degeneration in Ngsk Prnp0/0 mice.  相似文献   
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