Spectrally Efficient Cooperative Relay Networks using Signal Space Diversity

Cooperative relaying has received widespread attention in recent years from both academic and industrial communities. It offers significant benefits in enabling connectivity as well as in increasing coverage, power saving, spatial diversity and channel capacity. However, one of the main limitations of the conventional cooperative relaying system is the repetition of the received data by the relays, which reduces the spectral efficiency and the data rate. In this thesis, signal space diversity (SSD) based technique is proposed to incorporate into the conventional relaying system to enhance spectral efficiency, data rate and system performance. Firstly, SSD is introduced into a two-way cooperative relaying system with three-phase two-way decode-and-forward (DF) protocol. In this system, four symbols are exchanged in three time slots, thereby doubling the spectral efficiency and the data rate compared to the conventional three-phase two-way DF relaying system that uses six time slots to exchange the same four symbols. Next, SSD is employed in a dual-hop relaying system using DF protocol without a direct link between the source and the destination. In this system, two symbols are transmitted in three time slots as compared to four time slots to transmit the same two symbols in the conventional dual-hop DF relaying system. These proposed systems are designed to exploit the inherent diversity in the modulation signal-space by rotating and expanding the ordinary constellation. The improvement in spectral efficiency is achieved without adding extra complexity, bandwidth or transmit power. A comprehensive analysis of these proposed systems is carried out over Rayleigh fading channels, and closed-form expressions for various performance metrics, including error probability, outage probability and channel capacity, are derived and illustrated. An asymptotic approximation for the error probability is obtained and is used to illustrate the impact of system parameters and diversity gain on the system performance. The optimization of relay location and power allocation in these systems is also examined. Extensive Monte Carlo simulations are performed to ascertain the accuracy of the analytical results presented in the thesis. Indeed, it is observed that the use of SSD in cooperative relaying can play a major role in the system design and performance improvement

The influence of ischemic pre-conditioning and inhibition of the ubiquitin proteasome system on cardiac ischemic injury in a murine model

Myocardial infarction (MI) is a state when the flow of blood stops in a coronary artery or a succeeding vessel resulting in hypoxia leading to damage in the downstream cardiac tissue. Ischemia/reperfusion (I/R) injury leads to significant tissue damage and initiation of inflam-matory reactions. The roles of nuclear factor (NF)-κB and hypoxia inducible factor (HIF) in myocardium are still under discussion. It has been reported, that reduction of NF-κB activity by attenuation of the ubiquitin proteasome system (UPS) exerts bbeneficial effects on I/R injury in the myocardium. Furthermore, preceding short periods of ischemia before I/R injury like in Angina pectoris are known to protect the heart. Based on these findings, we hypothesized that repetitive short cycles of I/R will raise the cardiac HIF-levels and attenuate NF-κB levels, thus reduce inflammation. It was also hypothesized that pre- and post-conditioning with bortezomib (BZ), a blocker of UPS, will decrease ischemic injury, help to preserve cardiac function and facilitate remodeling after I/R. 9-12 weeks old female C57BL/6 mice underwent LAD constriction or sham surgery. Mice were divided into 5 different groups. Sham group; 60 min group treated with 15 min sham ischemia daily for 6 days prior to 1 x 60 min ischemia; repetitive group treated with 15 min ischemia daily for 6 days prior to 1 x 60 min ischemia, repetitive + BZ group received the same protocol complemented with 3 doses of BZ; 60 min ischemia + BZ group received the same treatment as the 60 min group complemented with 3 doses of BZ. 24 h post I/R injury changes were monitored in all groups. 21 d post ischemia success of remodeling was investigated in the sham, the 60 min, the 60 min + BZ and the repetitive groups. 24 h after I/R, 60 min group exhibited the biggest infarct size while all other groups developed significantly smaller infarct size. The 60 min group exhibited significantly reduced end-systolic pressure and ejection fraction as well as reduced dP/dtmax and dP/dtmin accompanied by an increased end-systolic as well as end-diastolic volume. All pre-conditioned groups exhibited less impaired cardiac function than the 60 min group. Interestingly, short periods of I/R, BZ treat-ment and combination of both in advance significantly reduced the malignant influence of I/R on the cardiac performance. Among the pre-conditioned groups the repetitive I/R treatment resulted in the best hemodynamic function 24 h after I/R. The investigation of inflammatory mediators 24 h after I/R revealed that all I/R groups exhibited increased levels of HIF-1α being highest in both BZ groups. IL-6 and IL-1β as well as ICAM-1 were expressed at the significantly highest levels in the 60 min + BZ group. Evaluation of the scar size after 21 d after I/R revealed that the scars of the animals in the 60 min and in the 60 min + BZ groups were significantly larger than in the sham and in the repetitive group, whereas the scar size did not differ significantly between later groups. Evaluation of the cardiac function revealed totally different results than after 24 h post I/R. Significantly reduced ejection fraction as well as decreased dP/dtmax and dP/dtmin was found in the 60 min group in comparison to the sham group. It is to be noted here that the end-systolic and end-diastolic pressures were compensated in 60 min group and in all other experimental groups. Surprisingly the 60 min + BZ group developed only slightly better cardiac function than the 60 min group. The repetitive group exhibited the most well preserved cardiac function in comparison to the I/R groups. Ejection fraction, end-systolic and end-diastolic pressure, and volume as well as dP/dtmax, dP/dtmin and cardiac output were found to be better preserved in the repetitive group than in any other experimental group. Taken together, the pre-conditioning with repetitive ischemia was successful in improving cardiac performance even in the long term. This study is the first one to report the upregulation of HIF-1α as result of BZ and repetitive I/R treatment. All experimental groups which were exposed to I/R exhibited increased HIF levels. In general, we did not gain the desired attenuation in inflammation by the BZ treatment. Also the BZ treatment was not found to be as successful as the repetitive treatment in long term. However, repetitive treatment cannot be applied in clinical setting. Thus, possibly another specific way to increase HIF level may help or a new protocol of BZ treatment has to be established in order to reduce I/R injury

Quality Assurance and Enhancement Mechanism in Tertiary Education of Pakistan: Recent Status, Issues and Expectations

Higher education commission of Pakistan is trying hard and strongly emphasizing to streamline the universities to adopt quality assurance and enhancement mechanism to improve the quality of Tertiary education and research. For this specific purpose, Higher Education Commission (HEC) has established Quality Enhancement cells (QEC) in public sector universities of Pakistan. The main purpose of these cells and centers are to enforce sound standards in higher education quality criteria in Pakistan. This paper would provide an insight about how to recognize the progress of Quality Enhancement Cells as per expectations and what measures are being taken to face the challenges for assuring and enhancing the quality of education in different institutions. This qualitative research study addresses and highlights the current status of quality enhancement in Tertiary Education of Pakistan with special reference to progress, issues and expectations in new era, together with this research paper also investigate the perspectives of Head of department and students regarding quality enhancement cells and quality of services, their working in universities for the sake of quality education. This paper mainly aimed to look into, Students teacher perspectives about quality enhancement in universities, Major success and issues for working and implementation of quality enhancement criteria in universities and Major expectations regarding quality enhancement in universities of Pakistan. The paper is based on the review of literature and interviews from 20 Head of Departments and 40 students from four public sector Federal universities to investigate the perceptions and expectations, progress and issues about quality enhancement mechanism and services in universities of Pakistan. The paper recommends that Quality Enhancement Framework should have following five foundations. Ownership of Quality and benchmarks, Enhancing the quality of student learning outcomes ,Involvement of all associated people ,awareness of International points of view, Independence, and association . 

A Corpus Stylistic Analysis of Speech and Thought Presentation in James Joyce’s Dubliners

The present article attempts to analyze the interaction between categories of speech and thought in James Joyce’s Dubliners quantitatively and qualitatively by applying Leech and Short Model (1981/2007). Excerpts of 2000-word length have been randomly selected and manually tagged to have the accurate annotation keeping in mind the contextual potential to recognize discourse categories in Joyce fiction and then corpus software AntConc (Laurence Anthony 2018) was used to get quantitative results. The present study is grounded within three separate but interrelated disciplines: Stylistics, Discourse Analysis, and Narratology. It is difficult to imagine an example of a narrative that does not contain a reference to or a quotation of someone’s speech or thoughts. To a large extent, the way we perceive a story depends upon the ways discourse is presented. This is something hard to demarcate the boundaries between them as the various modes have the potential to slip into one another. Special emphasis is given to variations between the three modes as well as to the instances of ambiguity created by their interplay. The article also compares findings with those described in Semino and Short (2004) for their corpus of 20th-century narrative fiction. Keywords:Corpus Stylistics, speech presentation, thought presentation, Leech and Short Model DOI: 10.7176/JLLL/81-05 Publication date:August 31st 202

Ethical Leadership and Employee Creative Performance: Discussing the mediating role of Employer Feedback Environment in Software Houses of Pakistan

Purpose: The basic purpose of this study was to explore employee creative performance, the contextual issues in the form of the leader’s style, and the feedback environment established by the leader in the Pakistani context. This study has presented a mechanism model for an understanding predictor of employee creative performance with the help of various theories. Methodology: Data was collected and analyzed from software houses registered in PSEB from 320 leader-employee dyads. Our research design was correlational. To reduce the common method biases, data was collected from two sources: leaders and their subordinates by sending the online questionnaire. To measure the uni-dimensionality and validity of construct EFA was performed through SPSS. Further, to assess the common method biases Heterotrait-Monotrait Ratio (HTMT) was used. SEM was used to compute, analyze, and prove relationships of proposed hypotheses and model fitness. CFA was used to confirm the theoretical measurement model, on AMOS 24 by using the rotated factor analysis. Finding: To sustain in this era of the competitive global business environment, organizations can stimulate employee creative performance by focusing on contextual and subjective variables. As per the findings, contextual factors like feedback environment associated with the leader regarding his style should be ethical, have a vital position in an organization for improving creative performance among employees. Specifically, the current study owns its justification and contribution to the literature and practical implications in various ways. Conclusion: The study indicates that the ethical style of leadership has a strong positive (+) association with the creative performance of employees as well as with the employer feedback environment. Also the employer feedback environment has partial mediation among ethical leadership and employee creative performance

Using IoT Innovation and Efficiency in Agriculture Monitoring System

Agriculture is undoubtedly a leading field for livelihoods in China. As the population increases, it is necessary to increase agricultural productivity. By capturing the support and the increment in production on farms, the need for freshwater used for irrigation increases too. Presently, agriculture accounts for 80% of overall water uptake in China. Unexpected overflow of water carelessly leads to waste of water. Therefore we created a programmed plant irrigation system with Arduino that mechanically supplies water to the plants and keeps it updated by transferring the message to user. Plant irrigation system employs the soil moisture sensor which controls a degree of moisture in the soil. If the humidity degree is lower, Arduino activates a pump of water to supply water to the system. The pump of water stops by design when the organism detects sufficient moisture in the ground. Each time the system is switched off or on, an electronic messaging is conveyed to the end-user through the IoT unit, informing the position of the soil moisture and the pump of water. A spray motor and the pump of water are grounded on the crane concept. Widely, this system is applicable for in small fields, gardens farms, etc. This design is entirely programmed and needed no human involvement. Furthermore, transmission of the sensor readings send through a Thing speak frequency to produce graphic elements for better inquiry. This study gathers the ideas of IoT (Internet of Things) with some engineering tools like machinery, artificial intelligence and use of sensors in an efficient way to respond current needs and extraction of resources by availing scientific methods and procedures that work on inputs. Moreover, this study further defines the engineering works that have been part of this field, but it requires more efficiency and reduction of energy as well as costs by adding more contribution of IoT in the field of agriculture engineering

Early detection of doxorubicin-induced cardiotoxicity and its prevention by carvedilol

Background: The objective was to detect doxorubicin (Dox) - induced myocardial injury at early stage by quantitative estimation of cardio specific protein, cardiac troponin I (cTnI) and to explore the cardioprotective effects of carvedilol.Methods: The study design was lab-based randomized controlled in-vivo in rabbits conducted from January to August 2012. Cardiotoxicity was produced by single intravenous injection of 12 mg/kg body weight (BW) of Dox in a group of rabbits, control group was treated with normal saline only and the rabbits of third group were pre-treated with carvedilol 30 mg/kg of BW for 10 days before injecting Dox.Results: Dox induced cardiotoxicity was depicted by markedly raised serum levels of cTnI, creatine kinase-MB, lactate dehydrogenase, and Grade 3 necrosis of the heart tissue in rabbits. The pre-treatment with carvedilol resulted in improved serum levels of these biomarkers and the histological picture of heart tissue.Conclusions: Quantitative serum estimation of cTnI detects the presence of cardiotoxicity much before cardiac dysfunctions can be revealed by any other diagnostic technique. It can lead to significant economic impact in the management of cancer patients because the troponin-negative subjects can be excluded from long-term cardiac monitoring programs that involve high costs imaging techniques. The outcome of Dox chemotherapy can be made successful with the concurrent use of carvedilol