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1.
Citrus is the leading fruit crop of Pakistan and exported to different parts of the world. Due to suitable weather condition, this crop is affected by different biotic factors which seriously deteriorate its quality and quantity. During the months of November 2018 to January 2019, citrus brown rot symptoms were recurrently observed on sweet oranges in National Agricultural Research Centre (NARC), Islamabad. Causal agent of citrus brown rot was isolated, characterized, and identified as Fusarium oxysporum. For environment‐friendly control of this disease, leaf extract of Azadirachta indica was used for the green synthesis of iron oxide (Fe2O3) nanoparticles. These nanoparticles were characterized before their application for disease control. Fourier transform infrared spectroscopy (FTIR) of these synthesized nanoparticles described the presence of stabilizing and reducing compounds like alcohol, phenol, carboxylic acid, and alkaline and aromatic compounds. X‐Ray diffraction (XRD) analysis revealed the crystalline nature and size (24 nm) of these nanoparticles. Energy dispersive X‐Ray (EDX) analysis elaborated the presence of major elements in the samples. Scanning electron microscopy (SEM) confirmed the spinal shaped morphology of prepared nanoparticles. Successfully synthesized nanoparticles were evaluated for their antifungal potential. Different concentrations of Fe2O3 nanoparticles were used and maximum mycelial inhibition was observed at 1.0 mg/ml concentration. On the basis of these findings, it could be concluded that Fe2O3 nanoparticles, synthesized in the leaf extract of A. indica, can be successfully used for the control of brown rot of sweet oranges.  相似文献   
2.
Environmentally sustainable construction is now recognised as a significant element of the broader sustainable development agenda and planners are being called upon to play a role in delivering more sustainable patterns of construction and development. This puts particular demands on the knowledge resources of planners since knowledge is implicated in the power relations between planners and developers. This paper examines the interrelationship between knowledge of environmentally sustainable construction and practice in planning departments. Drawing on a survey of and interviews with planners in London, it discusses the construction of knowledge within the dynamics of planning organisations and the potential for learning to promote a more sustainable built environment. Wenger's concept of communities of practice frames the analysis, alongside consideration of the translation of knowledge into bureaucratic and usable forms and the role of knowledge brokers in this process.  相似文献   
3.
Pearl millet, an underutilized crop, is a relatively good source of nutrients and has varied uses over cereals. New applications must be explored to popularize the millet. In the present study, flour and isolated starch from pearl millet cultivars—Kalukombu and Maharashtra Rabi Bajra (MRB)—were investigated for physicochemical properties, nutritionally important starch fractions and x-ray diffraction. The yield of starch was significantly low (Kalukombu: 34.5 g/100 g and MRB: 39.4 g/100 g) with traces of non-starch components (protein, fat, and ash) indicating its purity. Starch could be classified as non-waxy type based on low amylose content (2.86–4.96 g/100 g). Low amylose lead to fragility of swollen starch granules which disintegrated easily at 65°C as observed in swelling power and solubility. Isolated starch was characterized with low water- and oil-holding capacity which could be attributed to the low protein content and absence of fiber in the starch. However, MRB starch showed higher oil uptake compared to flour, possibly due to its larger surface area that increased oil uptake. X-ray diffraction patterns showed sharp peaks at 2θ values 15 and 23º and a diffused peak at 2θ of 17 and 18º which is characteristic of A-type pattern. Low resistant starch (RS) and high readily digestible starch (RDS) content observed in the isolated starch could be attributed to the A-type pattern of starch which is more susceptible to enzyme hydrolysis and also due to elimination of structural obstruction to amylase hydrolysis during the process of starch isolation and gelatinization.  相似文献   
4.
Recently, photocatalysis has received huge attention in order to overcome energy crisis worldwide. Many semiconductors, potential schemes and hierarchies have come to light during past few decades to fabricate efficient catalysts however, among all these methods heterostructures have taken the world by surprise. With the advancement in post-graphene 2D materials, van der Waals heterostructures have come to light exploring enhancement in photocatalysis. During a very short period a number of ZnO-based van der Waal heterostructures have taken the limelight in the field of photocatalysis. First principles calculations and DFT approach towards the heterostructures of GeC, GaN, WSe2, WS2 and other layered 2D materials unleased a series of properties and facts for the provision of enhanced catalysis. Reduction in bandgap of ZnO has also been observed which widens the pathways towards visible light irradiation. However, energy applications of zinc oxide are also fascinating feature as it can serve as a photoanode to replace TiO2. Whereas the famous hydrogen production, batteries and solar cells have also been fabricated by the use of this semiconductor.  相似文献   
5.
This review aims to illustrate the applications of Lawesson's reagent (LR) [2,4-bis(p-methoxyphenyl)-1,3,2,4-dithiadiphosphetane-2,4-disulfide] in the synthesis of naturally occurring medicinally important alkaloids. LR is primarily used for thionation; it is a versatile reagent employed for diverse transformations (cyclizations, rearrangements, and synthesis of heterocyclic compounds). The medicinal importance of alkaloids has also been concisely highlighted. The main focus of the review is the use of LR in the synthesis of natural alkaloids and only the thionation steps involved have been highlighted.  相似文献   
6.
Urooj A  Puttraj S 《Die Nahrung》1999,43(1):42-47
The rate of starch hydrolysis in ten cereal-based food preparations was studied using an in vitro dialysis system. The foods were incubated with human saliva and porcine pancreatin. The sugars released after 3 h digestion were expressed as digestibility index (DI), the percentage starch digested was determined and correlated with the degree of gelatinization (DG). Granule morphology was also investigated and related with starch availability for hydrolysis. Significant differences were observed in the in vitro starch digestibility of the 10 foods (P < 0.05). The DI ranged from 53 for chapathi to 78 for rice flakes. DI was inversely related to the protein (r = -0.79, P < 0.01), fat (r = -0.63, P < 0.05) and energy (r = -0.61, P < 0.01). Percent starch digested was inversely related to the insoluble (r = -0.49, P < 0.05) and total dietary fiber (r = -0.63, P < 0.01) content of the foods. The SEM results provided a better understanding of granular morphology on cooking and the effect of protein on limiting DG. The results suggest that carbohydrate foods of potential use in the therapeutic diets may be identified by their in vitro digestion characteristics.  相似文献   
7.
The effect of processing on the total dietary fibre (TDF) insoluble (IDF) and water-soluble (SDF) fractions as well as total (TS), available (AS) and resistant (RS) starch were studied in three legumes, viz. bengalgram (Cicer arietinum L.), Cowpea (Vigna unguiculata) and greengram (Vigna radiata). The processes studied were fermentation, germination, pressure-cooking and roasting. The dietary fibre (DF) content and its components were determined using the enzymatic-gravimetric method. The TS content was determined by the enzymatic method after solubilization with KOH. The DF content ranged from 23.2 to 25.6 g/100 g in the raw and 16.0 to 31.5 g/100 g in the processed legumes. All the processing treatments significantly decreased the SDF content and increased the IDF content of all the three legumes. The mean TS, AS and RS content of the raw legumes were similar, 46.9, 36.7 and 10.2 g/100 g respectively. AS content of all the legumes was reduced by the processing treatments, except pressure cooking. Correspondingly, higher amounts of RS were observed in the processed legumes, except pressure cooked, resulting in an increase in the TDF content.  相似文献   
8.
In view of the nutritionally important starch fractions it has become essential to generate data on starch digestibility of commonly used foods. The present investigation was aimed at evaluating the effect of processing on the nutritionally important starch fractions and the extent of in vitro starch digestibility in six roots and tubers commonly consumed in the Indian cuisine, using controlled enzymatic digestion with pancreatin and amyloglucosidase. The samples were subjected to open‐pan and pressure cooking. Rapidly available glucose (RAG) was also measured to derive a starch digestion index (SDI), a measure of the relative rate of starch digestion. The total starch and amylose content in the raw samples ranged from 41% (w/w) to 80% (w/w) (dry basis) and 0.91 to 26.80% (w/w) (dry basis), respectively. Pressure cooking of roots and tubers significantly (p<0.05) decreased the amylose content. The levels of the individual starch fractions varied depending on the cooking method and were characteristic for each sample. Processing significantly influenced the various starch fractions in yam and knollkohl. The SDI of samples subjected to the two cooking methods was only different for beet root and radish. Radish and carrot contained the highest dietary fiber content. The simple in vitro measurement of starch fractions could serve as a tool for characterizing dietary carbohydrates with respect to their digestion in the intestine.  相似文献   
9.
The antioxidant properties and total phenolic contents of methanol, acetone and water extracts of mulberry (Morus indica L.) leaves were examined. Various experimental models including iron (III) reducing capacity, total antioxidant capacity, DPPH radical scavenging activity and in vitro inhibition of ferrous sulphate-induced oxidation of lipid system were used for characterization of antioxidant activity of extracts. The three extracts showed varying degrees of efficacy in each assay in a dose-dependent manner. Methanolic extract with the highest amount of total phenolics, was the most potent antioxidant in all the assays used. In addition, the effect of temperature (50 °C and 100 °C), pH (3, 5, 7, 9 and 11) and storage (5 °C) on the antioxidant activity of methanolic extract was investigated. The antioxidant activity of the extract remained unchanged at 50 °C and was maximum at neutral pH. The extract stored at 5 °C in the dark was stable for 30 days after which the antioxidant activity decreased (p ? 0.05) gradually. On the basis of the results obtained, mulberry leaves were found to serve as a potential source of natural antioxidants due to their marked antioxidant activity.  相似文献   
10.
Suspicious mass traffic constantly evolves, making network behaviour tracing and structure more complex. Neural networks yield promising results by considering a sufficient number of processing elements with strong interconnections between them. They offer efficient computational Hopfield neural networks models and optimization constraints used by undergoing a good amount of parallelism to yield optimal results. Artificial neural network (ANN) offers optimal solutions in classifying and clustering the various reels of data, and the results obtained purely depend on identifying a problem. In this research work, the design of optimized applications is presented in an organized manner. In addition, this research work examines theoretical approaches to achieving optimized results using ANN. It mainly focuses on designing rules. The optimizing design approach of neural networks analyzes the internal process of the neural networks. Practices in developing the network are based on the interconnections among the hidden nodes and their learning parameters. The methodology is proven best for nonlinear resource allocation problems with a suitable design and complex issues. The ANN proposed here considers more or less 46k nodes hidden inside 49 million connections employed on full-fledged parallel processors. The proposed ANN offered optimal results in real-world application problems, and the results were obtained using MATLAB.  相似文献   
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