293 research outputs found
Role of Genetically Engineered System of Male Sterility in Hybrid Production of Vegetables
           Availability of cost effective mechanism/ method to produce large scale hybrid seed utilizing selected parental line is one of the important factors which ultimately determine the commercial viability of hybrid varieties. Manual emasculation increased cost of production, so use of various genetic mechanisms viz; male sterility, self incompatible, gynoccious lines, use of sex regulators and chemical hybridizing agents bases on relative importance in hybrid development in vegetable crops. Among these, genetic emasculation tools male sterility is commonly used for hybrid production. Recombinant DNA techniques have made it possible to engineer entirely new systems of male sterility by disturbing any or a number of developmental steps specifically required for the production of functional pollen within the microspore or for the development of any somatic tissues supporting the microspores. Although engineered male sterility systems are not currently in commercial use, except for possibly the barnase-barstar system, these are likely to have significant importance in future hybrid-breeding programs. The specific mechanisms causing male sterility in vegetables vary from species to species and are subject to influence by environment, and nuclear and cytoplasmic genes. Male sterility may be heritable or transient. It can be induced by anther culture, somatic cell culture, and somatic hybridization. However, the most significant development is the possibility of engineering male sterility by inserting cloned gene sequences which can disrupt any or more than one step during microsporogenesis. The male sterility was, in each case, heritable, associated with normal female fertility, and apparently maternal in its inheritance. Segregation of the transgene did not reverse the male sterile phenotype, producing stable, non transgenic male sterility. The reproducible transgenic induction of mitochondrial rearrangements in plants is unprecedented, providing a means to develop novel cytoplasmic male sterile lines for release as non-GMO or transgenic materials
ISOLATION OF ASTRAGALIN FROM IRAQI CHENOPODIUM ALBUM
Objective: Chenopodium album L is the species of the genus chenopodium. The Greek name Chenopodium means goosefoot. The plant is native to Asia and Europe. The analysis of the constituents of the Iraqi plant was performed using gas chromatography and high-performance liquid chromatography techniques.Methods: Thin-layer chromatography (TLC) and high-performance TLC chromatographic techniques were used for the detection and isolation of the active constituent found in the plant. Spectral analysis such as nuclear magnetic resonance (NMR) and UV was used to confirm the chemical structure of the compound isolated.Results: Astragalin was isolated and identified by comparison with standard kaempferol 3-O-β-glucoside (astragalin) which was detected as the major glycoside in the polar fraction of the plant. Further, identification of the compound was performed by 1H-NMR spectroscopy.Conclusion: Astragalin is the major flavonoid glycoside found in the plant.Â
A new four-dimensional hyper-chaotic system for image encryption
Currently, images are very important with the rapid growth of communication networks. Therefore, image encryption is a process to provide security for private information and prevent unwanted access to sensitive data by unauthorized individuals. Chaos systems provide an important role for key generation, with high randomization properties and accurate performance. In this study, a new four-dimensional hyper-chaotic system has been suggested that is used in the keys generation, which are utilized in the image encryption process to achieve permutation and substitution operations. Firstly, color bands are permuted using the index of the chaotic sequences to remove the high correlation among neighboring pixels. Secondly, dynamic S-boxes achieve the principle of substitution, which are utilized to diffuse the pixel values of the color image. The efficiency of the proposed method is tested by the key space, histogram, and so on. Security analysis shows that the proposed method for encrypting images is secure and resistant to different attacks. It contains a big key space of (2627) and a high sensitivity to a slight change in the secret key, a fairly uniform histogram, and entropy values nearby to the best value of 8. Moreover, it consumes a very short time for encryption and decryption
The Effect of Telephone Support on the Severity of Nausea and Vomiting in the First Trimester of Pregnancy in the Primiparous Women
Objective: to evaluate the effect of telephone support on the severity of nausea and vomiting in the first trimester of pregnancy in the primiparous women. Study Design: Randomized Control Trail. Study Place and Duration: Department of Obstetrics and Gynecology Bahawal Victoria hospital and primary health care facilities Bahawalpur, from January 2018 to June 2018. Material and methods: A total number of 72 patients referred to gynecology department of Nishtar hospital were included in this study. Patients were divided into two equal groups. Case group received telephone support while control group received standard care for the complaints of nausea and vomiting in pregnancy. There are 36 patients in each group. PUQE (pregnancy unique quantification of emesis\nausea) criterion was used to assess the severity of nausea and vomiting during pregnancy. Three outcome variables were assessed in order to evaluate the efficacy of the telephone support in case group, PUQE score, PUQE score severity and quality of life score. For continuous data independent t-test was applied, for nominal data chi-square test and for quality of life score Mann Whitney U-test was used. P value less than or equal to 0.05 was taken as statistically significant. Results: PUQE questionnaire was given to each patient and score was calculated. Mean PUQE score was 7.42±3.25 in the cases and 9.94±3.40 in the controls, the difference being statistically significant (p=0.002). Mild NVP, moderate NVP and severe NVP were observed in 20 (55.5%), 10 (27.8%) and 6 (16.7%) of the cases; and 8 (22.2%), 18 (50%) and 10 (27.8%) of the controls, respectively. The difference in PUQE severity was statistically different between the two groups (p=0.015). The quality of life score was also statistically much better (p=0.028) in the cases (8 (6-9)) than in the controls (7 (4.25-8)). Conclusion: Telephone support was significantly associated with better PUQE score and better quality of life score as compared to the standard care. But severity of PUQE score was not statistically significant when case and control groups were compared. Keywords: Nausea, Vomiting, Telephone, Primiparous, Pregnanc
Study of temperature, air dew point temperature and reactant flow effects on PEMFC performances using electrochemical spectroscopy and voltammetry techniques
A single PEMFC has been operated by varying the assembly temperature, the air dew point temperature and the anode/cathode stoichiometry rates with the aim to identify the parameters and combinations of factors affecting the cell performance. Some of the experiments were conducted with low humidified reactants (relative humidity of 12%). The FC characterizations tests have been conducted using in-situ electrochemical methods based on load current and cell voltage signal analysis, namely: polarization curves, EIS measurements, cyclic and linear sweep voltammetries (CV and LSV). The impacts of the parameters on the global FC performances were observed using the polarization curves whereas EIS, CV and LSV test results were used to discriminate the different voltage loss sources. The test results suggest that some parameter sets allow maximal output voltages but can also induce material degradation. For instance, higher FC temperature and air flow values can induce significant electrical efficiency benefits, notably by increasing the reversible potential and the reaction kinetics. However, raising the cell temperature can also gradually dry the FC and increase the risk of membrane failure. LSV has also shown that elevated FC temperature and relative humidity can also accelerate the electrolyte degradation (i.e. slightly higher fuel crossover rate) and reduce the lifetime consequently. PEMFC; Characterization; Electrochemical Impedance Spectroscopy; Cyclic Voltammetry; Linear Sweep Voltammetr
Antioxidant, anti-cholinesterase, anti-α-glucosidase and prebiotic properties of beta-glucan extracted from Algerian barley
Beta-glucan, such as barley-derived beta-glucan (BBG), are homopolysaccharides that have attracted attention by their nutritional and therapeutic properties. The aim of this study was to evaluate the antioxidant power of BBG extracted from local Algerian variety of barley (SAIDA 183), and its acetylcholinesterase, alpha glucosidase inhibitory activity as well as its prebiotic potential by fermentation with lactic acid bacteria isolated from camel’s milk, namely lactococcuslactisssplactis (Lc.l.l) and leuconostocmesenteroidesspmesenteroides (Ln.m.m). The results revealed that BBG exhibited low activity against DPPH and ferric-reducing power (IC50 4018.61 ± 656.69 and A0.5 at 359.88 ±63.64 µg/mL respectively), in contrast to other antioxidant tests (ABTS, Beta-carotene and CUPRAC) where BBG demonstrated a moderate activity (IC50 529.91 ±26.37, IC50 161.013±13.322, A0.5 529.79 ± 48.65 µg/mL). The scavenging ability of hydroxyl radical and superoxide radical by BBG with an IC50 at 2268.38±101.57 µg/mL and IC50 345.26± 62.32 µg/mL, respectively, while enzymatic inhibition by  BBG exhibited for AChE at IC50 859.164 ±64.46 μg/mL , BChE at IC50 at 725.470 ±30.95 , α-Amylase inhibitory activity at IC50 2986.785 ± 37.046 . The bacterial growth of the two strains used in this study is favorably affected by the use of BBG as the only carbon source, in comparison with glucose as a control. In light of these findings, it can be concluded that BBG have shown moderate antioxidant and enzyme inhibitory activities and can be used as a prebiotic by acting synergistically with probiotics in functional food matrices
Implementation of performance based contracting in Malaysia
Performance based contracting (PBC) has been used for several years in other countries.This procurement approach however can be considered new in Malaysia.In the past, this type of procurement was popular in lines such as production, maintenance, military, supply and service businesses.This paper studies about the challenges, benefits, tools, strategies and aspects of PBC that can be adopted from other countries and relates it for the purpose of improving Malaysian construction industry.Using outcomes from a series of open-ended interviews as well as from theoretical literature review, this paper also explores both success and failure factors of PBC and suggests a way in which it can be used in Malaysian construction industry. Finding from interviews indicates that Malaysian status of PBC implementation is not as expected. People are aware of PBC but the implementation is not well enough and it relates to the challenges from external and internal causes.However, tools like financial management and services improvement from PBC as well as encouragement and spread of awareness can be used to improve Malaysian construction industry
Complex network analysis of resting-state fMRI of the brain
Due to the fact that the brain activity hardly ever diminishes in healthy individuals, analysis of resting state functionality of the brain seems pertinent. Various resting state networks are active inside the idle brain at any time. Based on various neuro-imaging studies, it is understood that various structurally distant regions of the brain could be functionally connected. Regions of the brain, that are functionally connected, during rest constitutes to the resting state network. In the present study, we employed the complex network measures to estimate the presence of community structures within a network. Such estimate is named as modularity. Instead of using a traditional correlation matrix, we used a coherence matrix taken from the causality measure between different nodes. Our results show that in prolonged resting state the modularity starts to decrease. This decrease was observed in all the resting state networks and on both sides of the brain. Our study highlights the usage of coherence matrix instead of correlation matrix for complex network analysis
Characterization and prognostic value of mutations in exons 5 and 6 of the p53 gene in patients with colorectal cancers in central Iran
Background/Aims: We aimed to investigate the relation-ships among various mutations of the p53 gene and their protein products, histological characteristics, and disease prognosis of primary colorectal cancer in Isfahan, central Iran.
Methods: Sixty-one patients with colorectal adenocarcinoma were enrolled in the study. Mutations of the p53 gene were detected by single-stranded conformation polymorphism and DNA sequencing. The protein stability was evaluated by immunohistochemistry. Patients were followed up to 48 months.
Results: Twenty-one point mutations in exons 5 and 6 were detected in the tumor specimens of 14 patients (23%). Of those, 81% and 9.5% were missense and nonsense mutations, respectively. There were also two novel mutations in the intronic region between exons 5 and 6. In 11 mutated specimens, protein stability and protein accumulation were identified. There was a relationship between the type of mutation and protein accumulation in exons 5 and 6 of the p53 gene. The presence of the mutation was associated with an advanced stage of cancer (trend, p<0.009). Patients with mutated p53 genes had significantly lower survival rates than those with wild type p53 genes (p<0.01).
Conclusions: Mutations in exons 5 and 6 of the p53 gene are common genetic alterations in colorectal adenocarcinoma in central Iran and are associated with a poor prognosis of the disease
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