Ashish Yadav

Bio: Ashish Yadav is an academic researcher from Indian Institute of Technology Roorkee. The author has contributed to research in topics: Computer science & Network packet. The author has an hindex of 10, co-authored 37 publications receiving 319 citations. Previous affiliations of Ashish Yadav include Indian Council of Agricultural Research.

A Survey on Content Based Image Retrieval Systems

Abstract: Various content-based image retrieval techniques are available for retrieving the require and classify images, we are reviewing them. In our first section, we are tending towards some basics of a particular CBIR system with that we have shown some basic features of any image, these are like shape, texture, color and shown different techniques to calculate them. In the next section, we have shown different distance measuring techniques used for similarity measurement of any image and also discussed indexing techniques. Finally conclusion and future scope is discussed.

Antioxidant capacity and phenolics content of apricot (Prunus armeniaca L.) kernel as a function of genotype.

Abstract: Fourteen apricot genotypes grown under similar cultural practices in Trans-Himalayan Ladakh region were studied to find out the influence of genotype on antioxidant capacity and total phenolic content (TPC) of apricot kernel. The kernels were found to be rich in TPC ranging from 92.2 to 162.1 mg gallic acid equivalent/100 g. The free radical-scavenging activity in terms of inhibitory concentration (IC(50)) ranged from 43.8 to 123.4 mg/ml and ferric reducing antioxidant potential (FRAP) from 154.1 to 243.6 FeSO(4).7H(2)O μg/ml. A variation of 1-1.7 fold in total phenolic content, 1-2.8 fold in IC(50) by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and 1-1.6 fold in ferric reducing antioxidant potential among the examined kernels underlines the important role played by genetic background for determining the phenolic content and antioxidant potential of apricot kernel. A positive significant correlation between TPC and FRAP (r=0.671) was found. No significant correlation was found between TPC and IC(50); FRAP and IC(50); TPC and physical properties of kernel. Principal component analysis demonstrated that genotypic effect is more pronounced towards TPC and total antioxidant capacity (TAC) content in apricot kernel while the contribution of seed and kernel physical properties are not highly significant.

Attributes of Seabuckthorn (Hippophae rhamnoides L.) to Meet Nutritional Requirements in High Altitude

Abstract: The diet of humans living in different geographical and climatic regions of the earth varies greatly in both quantity and composition of foods. Evidence is accumulating that indicates that there is a high risk of malnutrition at high altitude because of the usual lack of fresh food and environmental factors. Lack of nutritious diet in the difficult terrain is a potential stressor that elicits oxidative stress. The excretion of minerals from the body is higher in high altitude condition. The altered nutritional requirement can be met to a large extend by regular consumption of locally grown fruits and vegetables. Results of analysis of Seabuckthorn growing in Leh valley of Trans-Himalaya showed the presence of high content of multivitamins including vitamin C (275 mg/100g), vitamin A (432.4 IU/100g), vitamin E (3.54 mg/100g), Riboflavin (1.45 mg/100g), Niacin (68.4 mg/100g), Pantothenic acid (0.85 mcg/100g), vitamin B-6 (1.12 mg/100g), and vitamin B-2 (5.4 mcg/100g). Similarly, mineral elements composition revealed high amount of minerals including potassium (647.2 mg/l), calcium (176.6 mg/l), iron (30.9 mg/l), magnesium (22.5 mg/l), phosphorous (84.2 mg/l), sodium (414.2 mg/l), zinc (1.4 mg/l), copper (0.7 mg/l), manganese (1.06 mg/l) and selenium (0.53 mg/l). Defence Science Journal, 2010, 60(2), pp.226-230 , DOI:http://dx.doi.org/10.14429/dsj.60.344

Antimicrobial activity of seed, pomace and leaf extracts of sea buckthorn ( Hippophae rhamnoides L.) against foodborne and food spoilage pathogens

Abstract: The present study was conducted to evaluate the total phenolic content (TPC) and antibacterial properties of crude extracts of sea buckthorn ( Hippophae rhamnoides L.) pomace, seeds and leaves against 17 foodborne pathogens. The methanolic extract of leaves exhibited high total phenolic content (278.80 mg GAE/g extract) and had low minimum inhibitory concentration (MIC) value of 125 μg/ml against Listeria monocytogenes . Salmonella typhimurium strain was found to be resistant against all tested extracts. The antilisterial activity of the methanolic extract of leaves was tested on carrots. Bacterial enumeration was significantly reduced by 0.15 to 0.31, 0.26 to 1.72 and 0.59 to 4.10 log cfu/g after 0 to 60 min exposure when treated with 125, 2500 and 5000 μg/ml extract, respectively. Thus, in addition to its use as a functional food ingredient, leaves extract from sea buckthorn (SBT) can possibly be used as a biosanitizer in food industries. Key words: Antimicrobial activity, Hippophae, Listeria monocytogenes , natural sanitizer, seabuckthorn.

Extraction of apricot kernel oil in cold desert Ladakh, India

Abstract: Apricot ( Prunus armeniaca L., Rosaceae) is the most important fruit crop of cold desert of Ladakh. Oil extracted from the sweet kernel is used for edible purpose while that of bitter kernel has religious, cosmetic and medicinal values. The oil is popular as body oil or massage oil, is known to relieve backache and joints ache. With the advancement of technology the cumbersome traditional method of oil extraction is slowly declining. However, the oil extracted by the traditional method is still being preferred due to its distinct smell. This paper describes the ancient traditional method of apricot kernel oil extraction still being practiced in some parts of Ladakh. Apricot ( Prunus armeniaca L., Rosaceae) is the most important fruit crop of cold desert of Ladakh. It covers 54% (707 ha) of total area under fruit crop in Leh district with the approximate annual yield of 2,956 MT/yr fresh fruit. Due to highly perishable nature, nearly 85% of the fruit is dried to extend its availability throughout the year 1 . The fruit crop is a major source of livelihood and is deeply associated with the tradition and culture of the region 2 . Apricot, locally known as Chuli , is broadly classified in Ladakh region into two categories based on taste of the kernel. Fruits with bitter kernel are called Khante meaning bitter, while those with sweet kernel are called Nyarmo meaning sweet. Sweet kernel is mainly consumed without processing as an important source of dietary protein, oil and fibre. Analysis of bitter apricot kernel of Ladakh region showed that the kernel is a rich source of oil (up to 54.21%), protein (17.75-22.56%), carbohydrate (21.16-35.26%), crude fibre (0.84-4.71%) and dietary fibre (6.03-22.24%) 3 . Apricot kernel oil is a rich source (94.4%) of unsaturated fatty acids rich in oleic acid (66.2%) and linoleic acid (28.2%) 4 . Oil extracted from the sweet kernel is used for edible purpose either in pure form or mixed with walnut oil. A spoonful of oil is mixed with finely ground roasted barley flour, salted tea and sugar to prepare a local dish called Phemar , which is served to guests and during festive occasion like marriage ceremony. The bitter kernel is used for extraction of oil which has religious, cosmetic and medicinal values. Even today, the oil is used as hair oil and is known to relieve backache and joints ache. The oil is popular as body oil and massage oil and is known for its ability to penetrate the skin without leaving an oily feel. Applying warm apricot oil mixed with a pinch of common salt on chest is known to give relief to patients with acidity.

基于Naive Bayes Classifiers的航空影像纹理分类

Abstract: 在Naive Bayes Classifiers模型中，要求父节点下的子节点（特征变量）之间相对独立，然而在现实世界中，特征与特征之间是非独立的、相关的。提出一种预处理方法，实验结果表明，该方法明显地提高了分类精度。

Biological Control Agents Against Fusarium Wilt of Banana

Abstract: In the last century, the banana crop and industry experienced dramatic losses due to an epidemic of Fusarium wilt of banana (FWB), caused by Fusarium oxysporum f.sp. cubense (Foc) race 1. An even more dramatic menace is now feared due to the spread of Foc tropical race 4. Plant genetic resistance is generally considered as the most plausible strategy for controlling effectively such a devastating disease, as occurred for the first round of FWB epidemic. Nevertheless, with at least 182 articles published since 1970, biological control represents a large body of knowledge on FWB. Remarkably, many studies deal with biological control agents (BCAs) that reached the field-testing stage and even refer to high effectiveness. Some selected BCAs have been repeatedly assayed in independent trials, suggesting their promising value. Overall under field conditions, FWB has been controlled up to 79% by using Pseudomonas spp. strains, and up to 70% by several endophytes and Trichoderma spp. strains. Lower biocontrol efficacy (42-55%) has been obtained with arbuscular mycorrhizal fungi, Bacillus spp., and non-pathogenic Fusarium strains. Studies on Streptomyces spp. have been mostly limited to in vitro conditions so far, with very few pot-experiments, and none conducted in the field. The BCAs have been applied with diverse procedures (e.g., spore suspension, organic amendments, bioformulations, etc.) and at different stages of plant development (i.e., in vitro, nursery, at transplanting, post-transplanting), but there has been no evidence for a protocol better than another. Nonetheless, new bioformulation technologies (e.g., nanotechnology, formulation of microbial consortia and/or their metabolites, etc.) and tailor-made consortia of microbial strains should be encouraged. In conclusion, the literature offers many examples of promising BCAs, suggesting that biocontrol can greatly contribute to limit the damage caused by FWB. More efforts should be done to further validate the currently available outcomes, to deepen the knowledge on the most valuable BCAs, and to improve their efficacy by setting up effective formulations, application protocols, and integrated strategies.

Biotechnological advances in guava ( Psidium guajava L.): recent developments and prospects for further research

Abstract: Guava (Psidium guajava L.), an important fruit crop of several tropical and sub-tropical countries, is facing several agronomic and horticultural problems such as susceptibility to many pathogens, particularly guava wilting caused by Fusarium oxysporium psidii, low fruit growth, short shelf life of fruits, high seed content, and stress sensitivity. Conventional breeding techniques have limited scope in improvement of guava owing to long juvenile period, self incompatibility, and heterozygous nature. Conventional propagation methods, i.e., cutting, grafting or stool layering, for improvement of guava already exist, but the long juvenile period has made them time consuming and cumbersome. Several biotechnological approaches such as genetic transformation may be effective practical solutions for such problems and improvement of guava. The improvement of fruit trees through genetic transformation requires an efficient regeneration system. During the past 2–3 decades, different approaches have been made for in vitro propagation of guava. An overview on the in vitro regeneration of guava via organogenesis, somatic embryogenesis, and synthetic seeds is presented. Organogenesis in several different genotypes through various explant selection from mature tree and seedling plants has been achieved. Factors affecting somatic embryogenesis in guava have been reviewed. Production of synthetic seeds using embryogenic propagules, i.e., somatic embryos and non-embryogenic vegetative propagules, i.e., shoot tips and nodal segments have also been achieved. Development of synthetic seed in guava may be applicable for propagation, short-term storage, and germplasm exchange, and distribution. An initial attempt for genetic transformation has also been reported. The purpose of this review is to focus upon the current information on in vitro propagation and biotechnological advances made in guava.