Ornithine decarboxylase activity, a clinical biomarker for evaluating cancer chemopreventive efficacy of phytomolecules

Biomarkers of cancer have made a strong traipse in predicting the disease pattern and contributed significantly to the understanding of tumour state, progression, characteristics and response to therapies. Polyamines such as putrescine, spermine and spermidine are cationic biomolecules essential for the cell cycle function and serve as excellent biomarkers of tumour progression. The polyamine biosynthesis is tightly regulated by ornithine decarboxylase, a highly inducible enzyme specific to pH, temperature, time and substrate concentration. The expression of this enzyme is very high during cell transformation and tumour progression leading to elevated level of polyamines. To measure the activity of ornithine decarboxylase an improved, easy, simple, reliable and cost-effective method has been developed utilizing small quantity of chemicals. The methodology is based on the cognizance that enzyme transforms L-ornithine hydrochloride substrate to a yellow coloured product putrescine soluble in pentanol, the absorbance of which was measured spectrophotometrically. The procedure is being utilized for evaluating cancer chemopreventive efficacy of phytomolecules. We have analyzed hundreds of molecules belonging to flavonoid, terpenes and alkaloid groups and very few were found to inhibit enzyme activity in a concentration dependent manner (0.4-50µg/mL). In addition, the molecules were also tested for their radical scavenging properties. Our results depict that molecules having phenolic groups and lactone rings in their structure are better inhibitors than their counterparts. The comparative analysis of the groups reassures flavonoids as better scavengers of radical formation and a positive correlation was observed among the nitric oxide and 2, 2-diphenyl-1-picrylhydrazyl inhibition (p<0.01). Further evaluation and augmentation may reveal novel ornthine decarboxylase inhibitors and cancer chemopreventive agents from plants

Choice of State Estimation Solution Process for Medium Voltage Distribution Systems

As distribution networks are turning into active systems, enhanced observability and continuous monitoring becomes essential for effective management and control. The state estimation (SE) tool is therefore now considered as the core component in future distribution management systems. The development of a novel distribution system SE tool is required to accommodate small to very large networks, operable with limited real time measurements and able to execute the computation of large volumes of data in a limited time frame. In this context, the paper investigates the computation time and voltage estimation qualities of three different SE optimization solution methods in order to evaluate their effectiveness as potential distribution SE candidate solutions

Demographic Transition and Youth Employment in Pakistan

There is convincing evidence that Pakistan has entered the demographic bonus phase; child dependency is declining and youth share in the total population is rising. This paper has examined youth employment in the context of demographic transition evidenced since the early 1990s. Changes in the level of educational attainment have also been analysed. The study has used the data from Pakistan Demographic Surveys and Labour Force Surveys carried out between 1990 and 2005. Findings of the study show that the benefits of demographic transition in terms of rising share of youth in the total population has partially been translated through development of their human capital and productive absorption in the local labour market. While the pace of human capital formation seems to be satisfactory in urban Pakistan, it is dismal in rural areas, particularly for females. High levels of both female inactivity across the education categories and unemployment for males as well as females urge a strong youth employment policy in Pakistan to reap the benefits of the ongoing demographic transition. Youth are a source of development, and a high priority may be placed on preparing them with the skills needed for their adjustment in the labour market.Demographic Transition, Youth, Employment, Pakistan

Evaluating Cartogram Effectiveness

Cartograms are maps in which areas of geographic regions (countries, states) appear in proportion to some variable of interest (population, income). Cartograms are popular visualizations for geo-referenced data that have been used for over a century and that make it possible to gain insight into patterns and trends in the world around us. Despite the popularity of cartograms and the large number of cartogram types, there are few studies evaluating the effectiveness of cartograms in conveying information. Based on a recent task taxonomy for cartograms, we evaluate four major different types of cartograms: contiguous, non-contiguous, rectangular, and Dorling cartograms. Specifically, we evaluate the effectiveness of these cartograms by quantitative performance analysis, as well as by subjective preferences. We analyze the results of our study in the context of some prevailing assumptions in the literature of cartography and cognitive science. Finally, we make recommendations for the use of different types of cartograms for different tasks and settings

Exploring sugar metabolism in bread wheat for improving drought tolerance

Remobilization of stem WSC is well known to contribute to grain yield in wheat. There is, however, extensive genetic variation in the contribution of stem WSC to grain yield under post-anthesis water-deficit. Fructan 1-exohydrolase (1-FEH) is one of the major enzymes contributing to WSC remobilisation and the maintenance of grain yield under water-deficit. 1-FEH has three isoforms (1-FEH w1, w2 and w3) that degrade β - (2-1) fructan linkages thus contributing to fructan remobilization to grain. This thesis investigated the functional role of the three isoforms of the 1-FEH gene in WSC remobilisation under post anthesis water-deficit. Individual performance of the three isoforms was investigated using the corresponding isoform mutation lines derived from the Australian wheat variety Chara. Results from glasshouse experiments showed that the mutation of isoform 1-FEH w3 slowed down WSC remobilisation under post anthesis water-deficit and reduced grain filling and yield. In contrast, mutations of 1-FEH w1 and w2 did not affect WSC remobilisation under water-deficit. This means that 1-FEH w3 plays the leading functional role in WSC remobilisation during grain filling under water-deficit. This differences in remobilisation of WSC components between the mutation lines correlated with the expressional differences of the three isoforms of the 1-FEH gene across the lines. In the 1-FEH w3 mutation line, the expression of the other two isoforms (1-FEH w2 and w1) had the same level as the non-mutated parental cultivar Chara. However, in the 1-FEH w2 and w1 mutation lines, 1-FEH w3 showed significantly higher expression compared to Chara. The results indicated that the functional loss of the isoforms 1-FEH w2 and w1 was made up by the higher expression of the isoform 1-FEH w3 but the functional loss of the 1-FEH w3 isoform was not compensated by the other isoforms. This explains the ability of 1-FEH w2 and w1 mutation lines to maintain the same pattern of WSC remobilisation as the non-mutated parental cultivar. It was also, revealed that the expressional differences of the isforms of the 1-FEH gene across different mutation lines significantly influenced the degradation of WSC and its components under post anthesis water-deficit. Fructan, a fructose-based polymer synthesized from sucrose by fructosyltransferases (FTs), is the main component of wheat stem WSC and is a major source of sugar supply under post anthesis water-deficit when photosynthesis is reduced. Quick degradation of fructan is essential to remobilise sugar to developing grain under water-deficit and this is facilitated by FEHs. The 1-FEH w3 mutation line showed slower degradation and remobilization of fructan compared to the 1-FEH w2 and w1 mutation lines and Chara. This slow degradation made the 1-FEH w3 mutation line partially susceptible to post anthesis water-deficit. Noticeably, differences in WSC component degradation and gene expression of 1-FEH isoforms only became evident under post anthesis water-deficit and not in well-watered plants. This thesis also characterised the 1-FEH gene mutation, by mapping and annotating the mutated region. The F1 seeds, developed by back crossing the 1-FEH w1, w2 and w3 mutation lines with Chara, were genotyped using the Infinium 90K SNP iSelect platform. Putative deletions were identified in the FEH mutation lines encompassing the FEH genomic regions. A total of 15, 20 and 15SNPs were identified within the mutation regions of 1-FEH w1 w2, and w3, respectively. Mapping analysis demonstrated that the mutation affected significantly longer regions than the target gene regions of 1-FEH w1, w3 and w2. From the annotation of the mutation regions, 8 and 6 non-target genes were discovered on chromosomes 6A and 6B, respectively. The annotation of the 1-FEH w2 mutated region was complicated by the presence of an extra three copies of the gene on chromosome 6D. Functional roles of the non-target genes was carried out following computational biology approaches and confirmed that none of the affected non-target genes were expected to have a direct influence on 1-FEH gene function. This study also ratified the association of the distinct role of the 1-FEH w3 gene in sugar remobilisation to the developing wheat grain. Accumulation of oligosaccharides at two seed developmental stages were examined in the 1-FEH w3 mutation line in comparison to Chara under well-watered and water-deficit conditions. This study successfully overcome the challenge of preparing 25 μm seed sections by adopting cryosectioning using egg white which provided compatibility with the mass spectrometric equipment and enabled the production of ions from the oligosaccharides by the laser. Hexose and its polymers were detected separately by the mass spectrometry imaging (MSI) without any enzymatic digestion thus providing information regarding the localisation of sugar accumulation within the tissues of developing seeds. The abundance and localisation pattern of the identified oligosaccharides was influenced by the post anthesis water-deficit treatment. Under water-deficit, the mutation of the 1-FEH w3 reduced the abundance of oligosaccharide accumulation in two stages of seed development (17 DAA and 22 DAA) indicating it pivotal role under post anthesis water-deficit. This is the first study to use MSI to explore sugar accumulation directly within the tissue of developing seeds of wheat. This thesis established the individual role of three isoforms of 1-FEH in remobilising WSC under post anthesis water-deficit and provides unequivocal evidence that 1-FEH w3 is taking the most vital role. This new insight into the distinct role of the 1-FEH gene isoforms under post anthesis water-deficit should assist in providing new gene targets for water-deficit tolerant wheat breeding in the future

MALDI-TOF: A Rapid Identification of Dairy Pathogens

Abstract The proposed research study is a field validation study to benchmark against proven methods, a new methodology for the detection of microorganisms (Matrix-Assisted Laser Desorption Ionization Time of Flight Mass Spectrometry or MALDI-ToF) isolated from dairy farm and critical for safety and quality. The MALDI-TOF is a relatively new molecular technique extremely advantageous in terms of cost effectiveness, sample preparation easiness, turn-around time and result analysis accessibility. Although already successfully deployed in clinical diagnostic, it has not been evaluated for agricultural applications yet. In the dairy industry, Mastitis causes the most financial loss and a rapid diagnostic method as MALDI-TOF, will assist in the control and prevention program of mastitis, in addition to the sanitation and safety level of the dairy farms and processing facility. In the present study, we prospectively compared MALDI-TOF MS to the conventional 16S rRNA sequencing method for the identification of environmental mastitis isolates (481) and thermoduric isolates of pasteurized milk (248). Among the 481 environmental isolates, 454 (94.4%) were putatively identified to the genus level by MALDI-TOF MS and 426 (88.6%) were identified to the species level, but no reliable identification was obtained for 17 (3.5%), and 27 (5.6%) discordant results were identified. Future studies can help to overcome the limitation of MALDI database and additional sample preparation steps might help to reduce the number of discordance in identification. In conclusion, our results show that MALDI-TOF MS is a fast and reliable technique which has the potential to replace conventional identification methods for most dairy pathogens, routinely isolated from the milk and dairy products. Thus it’s adoption will strengthen the capacity, quality, and possibly the scope of diagnostic services to support the dairy industry

Evaluating Growth Slowdowns: Does Middle-Income Trap Exist?

Growth theories suggest that the factors affecting growth at low-income and high-income countries can be different. If countries struggle to graduate to high-income growth strategies, they may find themselves stuck at some middle-income level. This phenomenon can be termed as middle-income trap . Using a panel of 145 countries over a period of 55 years, this study attempts to identify the existence of middle-income trap and its determinants. The aim of this study is to inspect whether the countries really get stuck at middle-income levels and if so, then pinpoint the factors associated with growth slowdowns. By employing panel probit estimations, this study has found evidence of the existence of middle-income trap. Most of the middle-income countries are sticky to their income levels and failed to make the additional leap necessary to achieve a high-income status. The study has identified the crucial factors associated with growth slowdowns and compared whether these factors in middle-income countries are any different than the low and high income countries. The results were validated using Bayesian Models and the findings suggest that the determinants of growth at middle and high income levels differ and middle income countries do need to change growth strategies to move smoothly to the high-income status. The recent anxiety over the issue of middle-income trap is not unfounded and this study affirms that the existing policies that have enabled few low-income counties to grow to middle income countries are not sufficient for transitioning to a high-income level. Middle-income countries need growth policies that are aimed at strong and sustained growth to help them to graduate to high-income status eventually