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

Domestic Violence and Leave Laws: How New York Can Improve Its Leave Policies Based on the Laws of Washington, D.C. and New Jersey

Although intimate partner violence often starts in the privacy of one’s home, its impact spills over in almost all aspects of the victim’s life. The effects of violence are tangible – physical and emotional harm to the person and their dependents, loss of educational or employment opportunities, financial problems, interactions with the criminal justice system, and ongoing legal issues. To address the loss of employment, federal and state governments have implemented leave laws to offer job protection for victims of intimate partner violence. Leave laws are an essential aspect of employment as the ability to take leave from work provides job security to employees who need to take time off to care for themselves and their families. However, differences in federal and state laws determine which type of employee is covered, for what length of time, and if they will be paid during their leave. While federal and some state laws provide job security for victims of intimate partner violence, there are many victims who are not protected under any law or the leave time afforded to them is inaccessible due to various factors. This Comment seeks to analyze the Family Medical Leave Act (“FMLA”) leave laws in New York and their impact on victims of intimate partner violence, and compare them to the leave laws of Washington, D.C. and New Jersey. Both Washington, D.C. and New Jersey offer more comprehensive and holistic protection for victims of intimate partner violence and should serve as a model for New York and the federal government

Incidence, prevalence, risk factors and health consequences of polypharmacy in adults in South Asia: a systematic review protocol

Objective: The objective of the systematic review is to summarize the incidence, prevalence, risk factors and health consequences of polypharmacy in adults in South Asia.Introduction: Several studies have been conducted in South Asia on the incidence, prevalence, risk factors and health consequences of polypharmacy in adults. Until now, no systematic review has been conducted on this topic.Inclusion criteria: Related epidemiological studies conducted on adults (aged 18 years and over) and residing in any country within South Asia (i.e. Afghanistan, Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan, and Sri Lanka) will be eligible for inclusion.Methods: MEDLINE, Embase, CINAHL, PsycINFO, BNI, Web of Science, Scopus and AMED databases will be searched to identify published studies. The search for unpublished studies will include EthOS, OpenGrey and ProQuest Dissertations and Theses. Databases will be searched from their inception dates and no language restrictions will be applied. The Joanna Briggs Institute systematic review methodology will be followed to conduct the review. Data synthesis will be conducted using narrative synthesis and meta-analyses, where appropriate

Delay models for static and adaptive persistent resource allocations in wireless systems

A variety of scheduling strategies can be employed in wireless systems to satisfy different system objectives and to cater for different traffic types. Static persistent resource allocations can be employed to transfer small M2M data packets efficiently compared to dynamic packet-by-packet scheduling, even when the M2M traffic model is non-deterministic. Recently, adaptive persistent allocations have been proposed in which the volume of allocated resources can change in sympathy with the instantaneous queue size at the M2M device and without expensive signaling on control channels. This increases the efficiency of resource usage at the expense of a (typically small) increased packet delay. In this paper, we derive a statistical model for the device queue size and packet delay in static and adaptive persistent allocations which can be used for any arrival process (i.e., Poisson or otherwise). The primary motivation is to assist with dimensioning of persistent allocations given a set of QoS requirements (such as a prescribed delay budget). We validate the statistical model via comparison with queue size and delay statistics obtained from a discrete event simulation of a persistent allocation system. The validation is performed for both exponential and gamma distributed packet inter-arrivals to demonstrate the model generality

A Short Review on the Development of Salt Tolerant Cultivars in Rice

Rice is staple food for half of the world. With a population of almost 9.6 billion by the year 2050, there is a dire need of developing techniques to improve the crop plants, not only in terms of better yield but also to withstand harsh environmental conditions and stresses like drought, temperature, flood and salinity. Salinity is second to drought stress and hence it is very important to develop crops tolerant to salinity stress. This review discusses the mechanisms of salt tolerance and the recent developments in understanding the complex tolerance phenomena. One way to address the salinity issue is to develop tolerant rice varieties using conventional and modern breeding techniques for which screening the rice germplasm for the varieties with desired traits is critical. Conventional methods to develop tolerant rice varieties are discussed along with modern biotechnology techniques are also discussed. Quantitative Trait Loci (QTL) and Marker Assisted Selection (MAS) are promising techniques. In addition to these modern techniques, some recent developments in the fields of transgenic plants, haploid breeding and Somaclonal variations have also been discussed. The limited knowledge about molecular and genetic mechanisms to tolerate abiotic stresses, however is a barrier to efficiently develop tolerant cultivars. A combination of conventional and modern biotechnology techniques could possibly open up the new ways

Performance Comparison of Particle Filter in Small Satellite Attitude Estimation

The drive towards miniaturization, coupled with the latest advances in onboard processing, has given rise to small satellite missions’ ability to use more complex attitude estimation algorithms to fit their progressive mission requirements. Earth observation missions typically require higher satellite attitude pointing accuracies to precisely control the satellite orientation. Hence, to provide greater confidence in the attitude estimation accuracies, new advanced algorithms are continuously being developed. Satellite attitude estimation must be performed autonomously in real-time whilst optimizing computational resources such as time and memory. Small satellite missions with higher complexities tend to demand more sophisticated requirements, which push the limits of classical attitude estimation methods. The Particle Filter is an advanced Bayesian estimation technique that has shown significant improvements in satellite attitude estimation. This work describes the Particle Filter and its implementation to the attitude and angular rate estimation for a 3U CubeSat in Low Earth Orbit, whilst comparing attitude estimation performance in two different settings: with three-axis magnetometer measurements; and with combined measurements from a three-axis magnetometer and sun sensors. This work further reports that for attitude determination in small satellites, the Particle Filter is a more accurate attitude estimator than the widely used Extended Kalman Filter. The Particle Filter yields attitude estimation accuracy of ±0.01°, while the Extended Kalman Filter attitude estimation accuracy is ±1°. Moreover, the results indicate that the use of an additional sensor improves the attitude estimation accuracy of the Particle Filter by 17%. It is essential to consider different sensor combinations as it helps select the most suitable sensor suite and attitude estimator for an individual small satellite mission

Exploring the Factors Affecting Online Trust in B2C E-Commerce Transactions in India: an Empirical Study

Purpose: The COVID-19 pandemic has led to a surge in e-commerce as millions of people were forced to stay at home and adopt digital channels for their purchases to avoid crowded supermarkets. It made the whole world look towards e-commerce as a one-stop solution for keeping markets alive. However, it came as an opportunity for digital fraudsters as a huge number of digital frauds were reported during this pandemic. Such incidents raised questions about online trust-related issues. Fake websites, insecure payment mechanisms, data theft, privacy breach, product reliability, etc., are a few of the reasons why many people are still not confident about using e-commerce platforms. When customers cannot physically touch, feel, and see the products, it becomes even more suspicious and raises serious uncertainty about the quality of the promised product and transaction setup in the e-commerce framework.   Design/Methodology/Approch: In this study, primary data was collected through structured questionnaires from e-commerce website users belonging to Generation Z and analyzed using Structural Equation Modelling and Path Analysis in IBM SPSS AMOS version 24.   Findings: Online Security, Online Privacy, and Website appearance were studied and found to have a significant positive impact on online trust. Online trust was also found to be a predictor of purchase intention. Online trust was also found to act as a full mediator between online security and purchase intention, online privacy, and purchase intention, and as a partial mediator between website appearance and purchase intention.   Research, Practical & Social Implications: The cross-sectional nature of this study makes it difficult for making inferences about causal relationships so new studies can adopt and check the utility of a longitudinal approach in this area. Furthermore, the data collected using convenience sampling had all young generation respondents, mostly college/university students. This current study takes only three antecedents of online trust with reference to a young generation; an exploratory study is needed here to find out new possible antecedents of developing online trust. Moreover, the appearance of the website is altogether a vast area to investigate for further development; very limited dimensions of the appearance of e-commerce websites are covered in this study

Fuzzy decision making in Business intelligence in the context of Gilgit-Baltistan

The main purpose of this paper is to investigate and implement fuzzy decision based on unequal objectives and minimization of regret for the decision making in the business intelligence and to compare the weight of products while the minimization of regret that uses regression of products in Gilgit-Baltistan. Here we will convert the verbal expressions in to linguistic variables and use in fuzzy decision making model, which influences the main two factors, one is effect of the influence on the product and second its payoff for the most effectiveness on the products