Fractional frequency reused based interference mitigation in irregular geometry multicellular networks

Recent drastic growth in the mobile broadband services specifically with the proliferation of smart phones demands for higher spectrum capacity of wireless cellular systems. Due to the scarcity of the frequency spectrum, cellular systems are seeking aggressive frequency reuse, which improve the network capacity, however, at the expense of increased Inter Cell Interference (ICI). Fractional Frequency Reuse (FFR) scheme has been acknowledged as an effective ICI mitigation scheme, however, in literature FFR has been used mostly in perfect geometry network. In realistic deployment, the cellular geometry is irregular and each cell experiences varying ICI. The main objective of this thesis is to develop ICI mitigation scheme that improves spectrum efficiency and throughput for irregular geometry multicellular network. Irregular Geometry Sectored-Fractional Frequency Reuse (IGS-FFR) scheme is developed that comprises of cell partitioning and sectoring, and dynamic spectrum partitioning. The cell-partitioning and sectoring allows full frequency reuse within an irregular geometry cell. Nevertheless, the sub-regions in an irregular cell have varying coverage areas and thus demands diverse spectrum requirements. The IGSFFR scheme is designed to dynamically allocate the spectrum resources according to the traffic demands of each sub-region. An enhanced IGS-FFR has been developed to optimally allocate the spectrum resources to individual users of each sub-region. Enhanced IGS-FFR has been realized using two different approaches, Auction based Optimized IGS-FFR (AO-IGS-FFR) and Hungarian based Optimized IGS-FFR (HO-IGS-FFR). The results show that IGS-FFR has significantly improved the cell throughput by 89%, 45% and 18% and users’ satisfaction by 112%, 65.8% and 38% compared to Reuse-1, Strict-FFR and FFR-3 schemes, respectively. The findings show that the ICI mitigation in IGS-FFR is reinforced by users’ satisfaction. As the number of sectors in IGS-FFR increases from 3 to 4 and 6, the cell throughput increase by 21% and 33% because of spatial diversity exploitation along with orthogonal sub-band allocation. AO-IGS-FFR and HO-IGS-FFR have further improved the cell throughput of the basic FFR-3 by 65% and 72.2%, respectively. HO-IGS-FFR performs 7% better than the AO-IGS-FFR at the expense of 26.7% decrease in the users’ satisfaction and excessive complexity. Although, AO-IGS-FFR compromises sub-optimal bandwidth allocation, it is a low complexity scheme and can mitigate ICI with high users’ satisfaction. The enhanced IGS-FFR can be deployed in future heterogeneous irregular geometry multicellular OFDMA networks

Control of the sugarcane borers Chilo infuscatellus and Tryporyza nivella by Bactospeine, a microbial pesticide

Chilo infuscatellus and Tryporyza nivella are the important sugarcane borers of Pakistan and are being controlled mostly by chemicals. Microbial control has not been tried in Pakistan. Therefore, grqnules and wettable powder of Bactospeine were tested against sugarcane borers at Mardan. Its granular formulation gave higher control than wettable powder

Financial Synergy in Mergers and Acquisitions in Saudi Arabia

Businesses today consider mergers and acquisitions a new strategy for their company’s growth. Companies aim to grow through sales’ increase, assets purchase, profits’ accumulation and market share gains. The better way for achieving these targets is by getting into either a Merger or an Acquisition. As a matter of fact, growth through mergers and acquisitions has been a critical part of the success of many companies operating in the new economy. Mergers and Acquisitions are an important factor in building up market capitalization. Based on three detailed and in depth structured interviews with major Saudi Arabian banks it has been found that, Mergers motivated by economies of scale should be approached cautiously. Companies should also approach vertical mergers cautiously because it is often difficult to gain synergy through a vertical merger and firms should also seek out mergers which allow the firm to acquire specialized knowledge. It has also been found that the firms should look for mergers that increase market power and avoid unrelated or conglomerate mergers

IMPACT OF 17-BETA ESTRADIOL AND MODERATE-INTENSITY EXERCISE ON MESENTERIC ARTERIAL FUNCTION OF UC DAVIS TYPE-2 DIABETES MELLITUS RATS

The studies in this dissertation were designed to investigate the impacts of estrogen (17-β estradiol/E2) and moderate-intensity exercise (MIE) on the mesenteric arterial (MA) function of the University of California Davis type-2 diabetes mellitus (UCD-T2DM) Rat model. Our recent report suggests that diabetes impairs MA vasorelaxation in both sexes of the UCD-T2DM model. Particularly, we reported that MA from prediabetic male rats showed a greater impairment compared to that in prediabetic females. However, when females become diabetic, they exhibit a greater vascular dysfunction than males. Therefore, the aim of the first study was to investigate whether female sex hormone, specifically E2, preserves the MA vasorelaxation in female UCD-T2DM rats at the early prediabetic state. For this study, age-matched healthy Sprague Dawley (SD) and prediabetic female UCD-T2DM rats were ovariectomized and subcutaneously implanted with either a placebo or E2 pellet for 45 days. Regular aerobic exercise is a well-known therapeutic intervention for endothelial dysfunction, insulin resistance, and cardiovascular disease (CVD) risk in diabetes. However, there are still debates about the duration, intensity, and underlying mechanisms of benefits of exercise against deleterious metabolic consequences in diabetic patients. In the second study outlined in this dissertation, we examined the impact of exercise training on vascular function and wall structure of the UCD-T2DM male rats. Age-matched male diabetic and SD control rats were randomly divided into sedentary and exercise-trained groups. The exercise-trained groups ran on a treadmill for eight weeks (1hr/day, 5days per week). For both studies (Studies I & II), metabolic parameters and MA responses to vasodilator and vasocontractile agents were determined. Furthermore, the expression of molecules associated with vascular signaling were also analyzed. The specific aims of our studies were to investigate whether E2 and moderate-intensity exercise (MIE) alter the 1) endothelium-dependent vasorelaxation (EDV) and vasoconstriction 2) relative contribution of endothelium-derived relaxing factors (EDRF) to vasorelaxation, and 3) expression of proteins associated with vascular signaling, in MA of UCD-T2DM rats. In the first study, we demonstrated that acetylcholine (ACh)-induced vasorelaxation was impaired in MA of ovariectomized (OVX) prediabetic UCD-T2DM rats. Our data also showed that E2 replacement improved MA relaxation in OVX prediabetic group to a similar level to that in control groups. Inhibition of cyclooxygenase (COX) by indomethacin (Indo) did not significantly affect the vascular responses in any groups, suggesting a minor role of COX metabolites in MA relaxation in the experimental groups. Inhibition of nitric oxide (NO) synthase (NOS) by L-NAME reduced vasorelaxation to ACh in control groups, but it did not completely abolish the vasorelaxation. We also showed that in control (healthy) groups, both NO and endothelium-derived hyperpolarizing factor (EDHF)-type relaxation were dominant in the MA relaxation of placebo and E2 treated rats. However, in prediabetic groups, L-NAME completely abolished the vasorelaxation, regardless of E2 treatment, suggesting a relative shift from EDHF-type relaxation to only NO-mediated relaxation in these groups. Furthermore, the sensitivity of MA to NO was significantly impaired in OVX prediabetic group, but E2 treatment enhanced the MA sensitivity to NO. Overall, our data suggest that a greater vasorelaxation in the E2 treated OVX prediabetic group could be partly attributed to the elevated role of NO or improved sensitivity of MA to NO in this group. The second study demonstrated that ACh-induced vasorelaxation of MA was significantly impaired in sedentary diabetic (DS) male rats. MIE significantly enhanced MA vasorelaxation in the exercise-trained diabetic (DE) group compared to the DS. However, no significant differences were observed between the vasorelaxation of control sedentary (CS) and control exercise-trained groups (CE). Inhibition of COX enhanced maximal vasorelaxation response (Rmax) to ACh in DS arteries suggesting an elevated contractile COX contribution in MA of this group which could possibly be due to the observed increase in COX expression in the DS group. Unlike the DS group, inhibition of COX did not affect the vasorelaxation responses to ACh in the DE group. The addition of L-NAME resulted in a reduction in ACh-induced relaxation of MA from both DS and DE groups. However, the effect of L-NAME was more prominent in the DS group compared to the DE group, suggesting a major contribution of NO in DS arteries. On the other hand, a preserved role of NO with an enhanced EDHF-mediated relaxation was observed in the MA vasorelaxation of the DE group. Our data on the elevated small conductance calcium-activated potassium channel (SKCa) expression level in MA taken from the DE group compared to that in the DS group may suggest a role for SKCa in increased EDHF-type relaxation in the DE group. Furthermore, DS arteries exhibited a higher contractile response, myogenic tone, and wall thickness than those in MA of DE. Overall, our data suggest that MIE reduced myogenic tone (DE vs. DS) and improved EDV in mesenteric arteries of diabetic rats, possibly via a shift from contractile COX activity to both NO and EDHF-type relaxation. In conclusion, the data generated in study-I suggest that estrogen may protect prediabetic female MA from early vascular dysfunction, possibly by elevating the contribution of NO to vasorelaxation as a compensatory mechanism to the loss of EDHF-type relaxation in this group. Although the results of the current study are in agreement with our previous report demonstrating a possible protective effect of female sex hormones in the MA function at prediabetic state, additional studies are needed to establish the specific role of E2 in the progression of vascular dysfunction in the diabetic state. Lastly, an intriguing observation of study-II was that MIE improved vasorelaxation and prevented the loss of EDHF-type relaxation in diabetic arteries. This was in addition to the changes induced to the wall thickness and myogenic tone in arteries of UCD-T2DM males. Given that sex differences play an important role in cardiovascular physiology, additional studies are needed to establish the specific role of MIE on vascular dysfunction in UCD-T2DM female rats and its underlying mechanisms

“A New Era in Advanced Heart Failure Therapy” : Left ventricular assist devices

This thesis aims to assess the current body of evidence and experiences with continuous flow-LVADs in the new era of advanced heart failure therapy. Furthermore, we investigate clinical outcomes, complications, and the impact of LVAD on end-organ function. In addition, an effort was made to predict these end-points in order to improve the selection criteria for LVAD therapy and current clinical practice

Developing a model of franchise business relationships

The business to business (b2b) relationship literature shows that the features of business relationship such as control, support, cooperation and power act a little differently in franchise business. Information on, and identification of the actions in the franchise business relationship, that can increase or diminish trust and commitment between both partners, is also scarce. Furthermore, how can these actions contribute to, solidify relationship; attaining over all business development, adding value, achieving synergy, and competitive advantage? This paper will briefly review literature on the relationship of the franchisor and franchisee, investigating its elements, actions that deteriorate it and providing a background that how and why the conflicts occur. From this it will is hypothesised that certain actions of the parties in relationship and suggest a generic conceptual model that be adopted and applied by both partners in order to increase cooperation and work together for over all business growth. This will help to add value, achieve competitive advantage and growth. This model could be applied in any environment. This paper will act as catalyst for development of a model for franchise business introduction and growth in CIS

Pulmonary hyalinising granuloma: a rare pulmonary disorder

Pulmonary hyalinising granulomas are rare, noninfectious fibrosclerosing lesions of the lung which can mimic metastatic disease. It was first described in literature by Engleman et al in the year 1977. Its etiology is unknown but they may be caused by an exaggerated immune response. The patient typically presents with cough, chest pain. dyspnoea or haemoptysis in association with multiple bilateral parenchymal nodules. We report the case of a 20 years old male who presented with a 12-month history of worsening dry cough. His plain chest radiograph and subsequent CT scan revealed bilateral pulmonary nodules. A CT guided biopsy of the pulmonary lesions was consistent with Pulmonary Hyalinising Granuloma [PHG]

Developing a model of franchise business relationships

The business to business (b2b) relationship literature shows that the features of business relationship such as control, support, cooperation and power act a little differently in franchise business. Information on, and identification of the actions in the franchise business relationship, that can increase or diminish trust and commitment between both partners, is also scarce. Furthermore, how can these actions contribute to, solidify relationship; attaining over all business development, adding value, achieving synergy, and competitive advantage? This paper will briefly review literature on the relationship of the franchisor and franchisee, investigating its elements, actions that deteriorate it and providing a background that how and why the conflicts occur. From this it will is hypothesised that certain actions of the parties in relationship and suggest a generic conceptual model that be adopted and applied by both partners in order to increase cooperation and work together for over all business growth. This will help to add value, achieve competitive advantage and growth. This model could be applied in any environment. This paper will act as catalyst for development of a model for franchise business introduction and growth in CIS

Determinants of entrepreneurial business relationship success.

The business development literature illustrates the importance of relationships on achieving targets and ensuring the sustainability of enterprises. In this paper the sphere of franchising which is essentially an entrepreneurial business is used to link measures of business relationships in the domains of trust, credibility, commitment, integrity, confidence and trust to the success of the business. It is found that irrespective of size and age of the franchise and business sector of operation that these relationships are important determinants of success. Although they do not act directly to enhance the prospect of success it is via their interactions that success arises

Pulmonary talcosis 10 years after brief teenage exposure to cosmetic talcum powder.

Pulmonary talcosis is a rare but debilitating variant of pneumoconiosis often presenting with isolated non-specific symptoms of progressive exertional dyspnoea or cough. Occupational exposure to talc dust and intravenous drug abuse are well-recognised aetiological factors with only a few cases related to cosmetic talc exposure being reported to date. The authors report a case of a young woman in whom a mere 4 month ritual of inhaling cosmetic talcum powder led to full-blown pulmonary talcosis being diagnosed 10 years later. The importance of a taking a pertinent history relating to environmental exposures in all patients presenting with respiratory symptoms is re-established here