Biological and molecular studies on potatovirus interactions using Potato virus S and Potato virus Y as model systems

Potato (Solanum tuberosum L.) is a staple food in the world. Potato virus Y (PVY; Potyvirus: Potyviridae) is an important virus that affects yield and quality of potatoes. PVY exists as biologically distinct strains: PVY-N induces systemic veinal necrosis in tobacco, PVY-O causes hypersensitive response (HR) in potato cultivars carrying the Ny gene and PVY-NTN produces necrotic rings on the tubers of sensitive potato cultivars. The vsiRNA profiles of three distinct PVY strains, ordinary (PVY-O), tobacco-veinal necrotic (PVY-N) and tuber-necrotic (PVY-NTN) strains were determined in potato cv. Russet Burbank. The frequency and distribution of vsiRNAs varied among different strains. PVY-NTN infected plants accumulated the highest population of PVY-vsiRNAs in comparison to plants infected with PVY-O and PVY-N. In PVY-infected plants, the 21 nt class was predominant whereas in healthy potato plants 24 nt class had the maximum population. VsiRNAs were derived from every nucleotide position of the PVY genome and certain hotspots were identified which produced relatively more vsiRNAs. Additionally, six novel microRNAs were found in PVY-infected plants. Potato virus S (PVS; Carlavirus: Betaflexiviridae) is another important potato virus distributed worldwide. The outcome of mixed infection of PVS and PVY was studied under controlled conditions in three potato cultivars, Defender, Desiree and Russet Burbank. Results showed that PVS has an antagonistic effect on PVY replication in mixed infection. The antagonistic effect was associated with less severe symptoms in dual infections as well as reduced PVY multiplication. Symptoms of PVS were not visible in Desiree and Russet Burbank plants except Defender which showed bronzing spots on the leaves. PVY symptoms included mosaic, mottling and leaf drop. It was found that the antagonistic effect of PVS on the replication of PVY is independent of host genetic background as the same pattern was found in all three potato cultivars. Potato cultivars such as Desiree carrying the Ny gene show HR to infection with the ordinary strain of PVY. In comparison to Russet Burbank, PVY levels in Desiree decreased with increasing number of days post-inoculation. The HR was found to be specific to PVY-O and was not elicited by infection by PVY-N or PVY-NTN

Impact of Environmental Factors on Tomato Leaf Curl Virus and Its Management through Plant Extracts

In the present study the correlation between TLCV incidence on different lines/varieties and the environmental factors (temperature, relative humidity and rainfall) was conducted. Furthermore, the whitefly population was also correlated with the environmental factors. It was revealed that there exists a strong positive and significant interaction in case of maximum and minimum temperature (8ºC-32ºC) and TLCV incidence but negative and significant interaction was observed in case of relative humidity and rainfall. The whitefly population showed a positive significant interaction with maximum and minimum temperatures prevailing. While whitefly population decreases with an increase in relative humidity and rainfall. It was also studied that the plant extracts (Neem, Bitter melon and Itsit) play a vital role in the management of TLCV in tomato plants. Where it was observed that the Plant extracts of Azadirachta indica (Neem), Momordica charantia (Bitter melon) and Trianthema monogyna linn. (Itsit)  at 5% concentration was effective in reducing the disease incidence. However, Neem extract at 5% concentration showed better results as compared to control and other plant extract i.e., Bitter melon and Itsit, in controlling the whitefly population and disease incidence of TLCV. Keywords: Tomato leaf curl virus, environmental factors, whitefly, plant extract

Customer Engagement Plans for Peak Load Reduction in Residential Smart Grids

In this paper, we propose and study the effectiveness of customer engagement plans that clearly specify the amount of intervention in customer's load settings by the grid operator for peak load reduction. We suggest two different types of plans, including Constant Deviation Plans (CDPs) and Proportional Deviation Plans (PDPs). We define an adjustable reference temperature for both CDPs and PDPs to limit the output temperature of each thermostat load and to control the number of devices eligible to participate in Demand Response Program (DRP). We model thermostat loads as power throttling devices and design algorithms to evaluate the impact of power throttling states and plan parameters on peak load reduction. Based on the simulation results, we recommend PDPs to the customers of a residential community with variable thermostat set point preferences, while CDPs are suitable for customers with similar thermostat set point preferences. If thermostat loads have multiple power throttling states, customer engagement plans with less temperature deviations from thermostat set points are recommended. Contrary to classical ON/OFF control, higher temperature deviations are required to achieve similar amount of peak load reduction. Several other interesting tradeoffs and useful guidelines for designing mutually beneficial incentives for both the grid operator and customers can also be identified

Study and analysis of mobility, security, and caching issues in CCN

Existing architecture of Internet is IP-centric, having capability to cope with the needs of the Internet users. Due to the recent advancements and emerging technologies, a need to have ubiquitous connectivity has become the primary focus. Increasing demands for location-independent content raised the requirement of a new architecture and hence it became a research challenge. Content Centric Networking (CCN) paradigm emerges as an alternative to IP-centric model and is based on name-based forwarding and in-network data caching. It is likely to address certain challenges that have not been solved by IP-based protocols in wireless networks. Three important factors that require significant research related to CCN are mobility, security, and caching. While a number of studies have been conducted on CCN and its proposed technologies, none of the studies target all three significant research directions in a single article, to the best of our knowledge. This paper is an attempt to discuss the three factors together within context of each other. In this paper, we discuss and analyze basics of CCN principles with distributed properties of caching, mobility, and secure access control. Different comparisons are made to examine the strengths and weaknesses of each aforementioned aspect in detail. The final discussion aims to identify the open research challenges and some future trends for CCN deployment on a large scale

Impact of Bank Profitability on Default Risk: Empirical Evidence from Pakistan

This empirical study investigates the effect of the bank-specific determinants of bank profitability on the default risk of the banks listed on the Stock Exchange of Pakistan. For this purpose, the study considers balanced panel data covering the period 2009-2018 for the 20 selected commercial banks of Pakistan, and the probability of default is used to measure the default risk of these banks. The bank profitability is measured using bank-specific determinants such as the net interest margin, non-interest income to total assets, return on assets, return on equity, and spread ratios. The empirical findings of the fixed effects model reported that net interest margin, non-interest income, and spread ratio are the significant determinants of default risk. The findings highlight that the bank profitability determinants can act as early warning signs of a bank’s deteriorating stability level. The study recommended that the central bank of Pakistan should guide the commercial banks to disclose the probability of default values in their financial reports. The study also suggested that the risk management department of a bank should consider these bank-specific determinants of profitability to manage default risk

Socio-Economic Barriers to Women's Higher Education: A Study of Tribal Area Barthi

The aim of the present had to identify the various barriers females face in their higher education. The main issue women are facing in their higher education is a tradition of that culture. Education improves the socio-economic status of women and gives them awareness in life. Tehsil Taunsa Sharif was selected as the universe for research. All the female of tehsil Taunsa Sharif was the target population of this research. The sample size of this research was 100 families of Taunsa Sharif. The researcher had selected the respondents with the help of Simple Random Sampling. Pakistani society has complex dynamics due to the diversity in cultures and traditions in the whole of the country. Findings of research evidence indicate that in the effect of varieties of initiatives some positive changes and progress have been made in making education accessible to all

A Taxonomy on Misbehaving Nodes in Delay Tolerant Networks

Delay Tolerant Networks (DTNs) are type of Intermittently Connected Networks (ICNs) featured by long delay, intermittent connectivity, asymmetric data rates and high error rates. DTNs have been primarily developed for InterPlanetary Networks (IPNs), however, have shown promising potential in challenged networks i.e. DakNet, ZebraNet, KioskNet and WiderNet. Due to unique nature of intermittent connectivity and long delay, DTNs face challenges in routing, key management, privacy, fragmentation and misbehaving nodes. Here, misbehaving nodes i.e. malicious and selfish nodes launch various attacks including flood, packet drop and fake packets attack, inevitably overuse scarce resources (e.g., buffer and bandwidth) in DTNs. The focus of this survey is on a review of misbehaving node attacks, and detection algorithms. We firstly classify various of attacks depending on the type of misbehaving nodes. Then, detection algorithms for these misbehaving nodes are categorized depending on preventive and detective based features. The panoramic view on misbehaving nodes and detection algorithms are further analyzed, evaluated mathematically through a number of performance metrics. Future directions guiding this topic are also presented

The Influencing Factors of the Career Pathway for Health Professions’ Education

Objectives: In this study our objective was to identify and explore the factors that influenced the choice of those Medical and Dental Graduates who chose HPE as a sole career, as to our knowledge there is yet to be an attempt exploring the factors influencing the choice of HPE as a sole career. Significance of Study: Doctors and dentists have a wide variety of specialties. One such specialty is HPE that revolves around all three divisions, undergraduate, postgraduate and the continuing professional development, of a Medical and Dental Practitioner. In Pakistan, there is a varied perception of this specialty despite it encompassing the very essence in the journey of a medical and dental graduate, aiming to produce a population of ethical, knowledgeable, skilled and up-to-date professionals. (9-11)To address these, a formal process of training is required with enrollment in an HPE Program. This study has been designed to identify and explore the choice of those Graduates who have opted HPE as a sole career.   1.       Materials and methods Study Design: A qualitative exploratory design was employed to explore the factors influencing specialty preference by phenomenology(12) Study Setting and Duration: The study was conducted at Islamic International Medical College, Riphah International University, Islamabad. Data was collected over four months, February to May, and the total duration of the study was from February to June. Study Population: All medical and dental graduates who had completed a post-graduate HPE qualification and had at least five years’ experience. Population size: A total 18 doctors were identified after the inclusion and exclusion criteria. However, only 6 agreed to participate in the study. Inclusion Criteria: Medical and Dental graduates that had opted post-graduate HPE qualification

Conflict in Waziristan

In the wake of 9/11 attacks and the U.S., lead “War on Terrorism”, Pakistan launched a military operation in Waziristan. A ground for the nourishment of terrorist, today, the government has launched a full-scale operation in North Waziristan against the denial and elimination of terrorist ideology. Military operation conducted has positive and negative impacts and it alone is not the solution for conflict resolution. Learning lessons from other movements of insurgency and their post-conflict efforts‟, our success for ending the seven years of insurgency, will be judged through the effort‟s made by the government and our model of peacemaking for the state.&nbsp