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91.
Elaborate one-dimensional photonic crystals are constructed from a variety of organic and biopolymers, which can be dissolved or melted, by templating the solution-cast or injection-molded materials in porous silicon or porous silicon dioxide multilayer (rugate dielectric mirror) structures. After the removal of the template by chemical dissolution, the polymer castings replicate the photonic features and the nanostructure of the master. We demonstrate that these castings can be used as vapor sensors, as deformable and tunable optical filters, and as self-reporting, bioresorbable materials.  相似文献   
92.
A field experiment was conducted during rainy seasons of 2009 and 2010 at New Delhi, India to study the influence of varieties and integrated nitrogen management (INM) on methane (CH4) emission and water productivity under flooded transplanted (FT) and aerobic rice (AR) cultivation. The treatments included two rice (‘PB 1’ and ‘PB 1121’) varieties and eight INM practices including N control, recommended dose of N through urea, different combinations of urea with farmyard manure (FYM), green manure (GM), biofertilizer (BF) and vermicompost (VC). The results showed 91.6–92.5 % lower cumulative CH4 emission in AR compared to FT rice. In aerobic conditions, highest cumulative CH4 emission (6.9–7.0 kg ha?1) was recorded with the application of 100 % N by organic sources (FYM+GM+BF+VC). Global warming potential (GWP) was significantly lower in aerobic rice (105.0–107.5 kg CO2 ha?1) compared to FT rice (1242.5–1447.5 kg CO2 ha?1). Significantly higher amount of water was used in FT rice than aerobic rice by both the rice varieties, and a water saving between 59.5 and 63 % were recorded. Under aerobic conditions, both rice varieties had a water productivity of 8.50–14.69 kg ha?1, whereas in FT rice, it was 3.81–6.00 kg ha?1. In FT rice, a quantity of 1529.2–1725.2 mm water and in aerobic rice 929.2–1225.2 mm water was used to produce one kg rice. Thus, there was a saving of 28.4–39.6 % total water in both the rice varieties under AR cultivation.  相似文献   
93.
The ability of abscisic acid (ABA) to inhibit synthesis of the phytoalexin, rishitin, in aging arachidonic acid-treated potato tuber discs was studied in a time-restricted manner. The extent of inhibition was decreased to near zero when the ABA was applied up to 24 h after cutting the discs, regardless of whether the arachidonic acid treatment was at 0 or 24 h after cutting. Application of ABA to potato discs more than 24 h after cutting the discs caused high levels of inhibition in discs treated with arachidonic acid at 24 h, but not in discs treated with arachidonic acid at 0 h. Apparently ABA interferes with at least two separate aging events that are required for phytoalexin synthesis. One event is initiated by cutting the potato tissue, and the other by the arachidonic acid treatment.  相似文献   
94.
Tuber resistance toPhytophthora infestans was studied in relation to physiological age in tubers of the cultivars Atzimba, Katahdin, Kennebec, and Sebago. Resistance to race1,2,3,4 was evaluated in freshly harvested tubers, and tubers stored at 5 C for up to 215 days. Atzimba tubers were highly resistant when freshly harvested but became increasingly susceptible as they aged physiologically. Tubers of the other three cultivars were susceptible when freshly harvested and also when aged. Further, 57 tuber selections from among 11 crosses initially gave resistant reactions. However, after storage for six months at 5 C, 26.3% of the selections remained resistant, 22.8% were moderately resistant, 31.6% moderately susceptible, and 19.3% fully susceptible.  相似文献   
95.
Two major lectins, MBL-I and MBL-II, were purified fromVigna radiata L. seeds using ion-exchange and gel filtration chromatography techniques. MBL-I was found to be a tetramer with native M.W. of 132 kDa and subunit M.W. of 33 kDa having α-galactosidase activity. MBL-II consisted of two monomeric lectins with M.W. of 94 kDa and 89 kDa which were associated mainly with β-galactosidase activity. Both MBL-I and MBL-II are D-galactose-specific lectins.  相似文献   
96.

Objective

To determine the anti-inflammatory efficacy of choline in vivo and in vitro and to investigate the anti-inflammatory mechanisms of choline.

Study design

Randomized, controlled studies.

Animals

In vivo trials used 16 Romney sheep. In vitro experiments utilized RAW 264.7 mouse macrophage cells.

Methods

Hypoxaemia induced in 16 sheep by intravenous (IV) injection of 50 μg kg–1 xylazine, an α-2 agonist, was measured in sheep at 0, 1 and 4 minutes using arterial blood gas analysis with and without 50 mg kg–1 IV choline chloride premedication. Cell culture studies used enzyme-linked immunosorbent assay to measure the release of tumour necrosis factor (TNF-α) from lipopolysaccharide (LPS) stimulated macrophages with and without choline chloride premedication. TNF-α release was compared to thalidomide suppressed and untreated cells.

Results

Choline premedication in sheep mitigated a reduction in arterial partial pressure of oxygen (PaO2) but did not prevent development of clinically significant hypoxaemia. Decrease in mean PaO2 of choline treated sheep was 6.36 kPa (47.7 mmHg) compared to 9.81 kPa (73.6 mmHg) in control sheep. In vitro studies demonstrate that choline administered concurrent with LPS activation did not significantly suppress TNF-α expression but that treatment of cells with choline 10 minutes prior to LPS activation did significantly suppress TNF-α expression. Choline pretreated cells expressed 23.99 ± 4.52 ng mg–1 TNF-α while LPS only control cells expressed 33.83 ± 3.20 ng mg–1.

Conclusions

Choline is able to prevent macrophage activation in vitro when administered prior to LPS activation and may reduce hypoxaemia in sheep developing pulmonary oedema after xylazine administration. This effect requires premedication with choline.

Clinical relevance

Pharmacological manipulation of autonomic inflammatory responses holds promise for the treatment of inflammation. However, the complex cellular mechanisms involved in this reflex means that an adequate therapy should approach multiple pathways and mechanisms of the inflammatory response.  相似文献   
97.
The Brassicas are affected by several diseases, of which black rot, Xanthomonas campestris pv. campestris (Pam.) Dowson (Xcc), is one of the most widespread and devastating worldwide. The black rot bacteria causes systemic infection in the susceptible plants and penetrate the plants through the hydathodes or wounds. Typical disease symptoms are ‘V’ shaped necrotic lesions appearing from the leaf margins with blackened veins. Periodic outbreaks of the black rot pathogen have occurred worldwide, especially in the continental regions, where high temperatures and humidity favor the incidence of disease occurrence causing huge yield loss. The challenge to control the losses in vegetable brassicas production is made more difficult by the adverse climatic changes and evolution of new pathogenic races. The development of black rot resistant hybrids/varieties is the most reliable long term practical solution for effective disease control. Identification of new resistant genetic resources, tightly linked markers with resistance loci and QTL mapping would facilitate the breeding programme for black rot resistance. Information regarding genetics of resistance and mapping of resistance genes/QTLs will accelerate the marker assisted resistance breeding in brassica crops against Xcc. In future we need to identify the race specific candidate genes for and their validation through transgenics and gene expression. Moreover, it is imperative to identify functional markers for resistance genes through identification of R gene families and their relationship with resistance expression. This comprehensive review will help the researchers working in this area to understand the dynamics of black resistance breeding and to formulate future breeding strategies.  相似文献   
98.
The Brassica vegetable crops are rich source of important antioxidant compounds having anticancer and health promoting properties. Development of F1 hybrids with better nutritional traits is one of the main breeding objectives in different vegetable crops. Our study is the first report of determining heterotic combinations utilizing cytoplasmic male sterile (CMS) and doubled haploid (DH) inbred lines for antioxidant compounds in snowball cauliflower. Twenty genetically diverse Ogura CMS lines of cauliflower and six DH male fertile inbred lines were crossed to develop 120 F1 hybrids in line?×?tester mating design. The resulting 120 test cross progenies along with 26 parents and 4 standard checks were evaluated in 10?×?15 alpha lattice design with three replications during next cropping season. The CMS lines Ogu33-1A, Ogu122-5A and Ogu119-1A were good general combiner and CMS line Ogu118-6A was poor general combiner for majority of traits. Most of the heterotic hybrids were associated with high positive SCA effects. The proportions of σ2A/D and \(\upsigma^{2}_{\text{gca}} /\upsigma^{2}_{\text{sca}}\) ratios were less than unity in all the cases indicating preponderance of non-additive gene action in the genetic control of all the traits. Highest number of heterotic hybrids with SCA effects in desired positive direction was recorded for ascorbic acid content and phenolic content followed by total carotenoid content. The F1 hybrids with better combining ability and better per se performance could be useful in accumulation of favourable allele for higher concentration of important anti-oxidant compounds.  相似文献   
99.
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