Enhanced multi-user DMT spectrum management using polynomial matrix decomposition techniques

This thesis researches the increasingly critical roles played by intelligent resource management and interference mitigation algorithms in present-day input multiple output (MIMO) communication systems. This thesis considers the application of polynomial matrix decomposition (PMD) algorithms, an emerging broadband factorisation technology for broadband MIMO access networks. Present DSL systems’ performance is constrained by the presence of interference (crosstalk) between multiple users sharing a common physical cable bundle. Compared to the traditional static spectrum management methods that define their survival to the worst-case scenarios, DSM methods provides some degree of flexibility to both direct channel and noise parameters to improve evolvability and robustness significantly. A novel crosstalk-aware DSM algorithm is proposed for the efficient management of multi-user DSL systems. Joint power allocation procedures are considered for the proposed single-channel equalisation method in DSL access networks. This thesis then shows that DSM can also benefit overdetermined precoding-equalisation systems, when the channel state information (CSI) parameters call for a specific decision feedback criterion to achieve a perfect reconstruction. A reasonable redundancy is introduced to reformulate the original multi-user MIMO problem into the simplest case of power management problem. DSM algorithms are primarily applied to solve the power allocation problem in DSM networks with the aim of maximising the system attribute rather than meeting specific requirements. Also, a powerful PMD algorithm known as sequential matrix diagonalisation (SMD) is used for analysing the eigenvalue decomposition problem by quantifying the available system resource including the effects of the crosstalk and its parameters. This analysis is carried out through joint precoding and equalisation structures. The thesis also investigates dynamic interference mitigation strategies for improving the performance of DSL networks. Two different mitigation strategies through a decision feedback equalisation (DFE) criterion are considered, including zero-forcing (ZF) and minimum mean square error (MMSE) equalisers. The difference between ZF and MMSE equalisations is analysed. Some experimental simulation results demonstrate the performance of both ZF and MMSE equalisation under the DFE equalisation constraint settings. Model reduction on the MMSE equalisation is thus applied to balance the crosstalk interference and enhance the data-rate throughput. Finally, the thesis studies a multi-user MIMO problem under the utility maximisation framework. Simulation results illustrate that the power allocation of multi-user DSL transmission can be jointly controlled and the interference can often be mitigated optimally on a single user basis. Driven by imperfect CSI information in current DSL networks, the research presents a novel DSM method that allows not only crosstalk mitigation, but also the exploitation of crosstalk environments through the fielding of versatile, flexible and evolvable systems. The proposed DSM tool is presented to achieve a robust mitigating system in any arbitrary overdetermined multi-user MIMO environment. Numerical optimisation results show that the mitigation of crosstalk impairment using the proposed DSM strategy. The design and implementation of the proposed DSM are carried out in the environment of MATLAB

Effectiveness of Monetary Policy and the Growth of Industrial Sector in China

China is viewed as the pillar of Emerging Market Economies (EMEs), deems to surpassed United State, and become the topmost industrialized country in the world with the prospects of major shift in the future world power. However, growth rate has slow down since the third quarter of 2014. Through this paper, we aim at investigating the impacts of monetary policy on industrial sector growth, and determine whether the long-run industrial sector growth in China can be foster by the effectiveness of monetary policy. It also examines the interrelationships among the variables employed and determines the steady-state relationships between industrial sector growth and monetary policy. Time-series econometric techniques such as unit roots, ARDL and ECM are employed to monthly data for the year 1994:1 to 2013:12.According to the empirical results derived, the effectiveness of monetary policy significantly affects industrial sector growth and the short-run impact of monetary policy on industrial output production is established

The likelihood of having serum level of PSA of ≥4.0 ng/mL and ≥10.0 ng/mL in non-obese and obese Nigerian men with LUTS

AbstractObjectiveThis study was undertaken to determine the likelihood of having serum total prostate specific antigen (PSA) levels ≥4.0 ng/mL and ≥10.0 ng/mL among a cohort of non-obese and obese Nigerian men with lower urinary tract symptoms (LUTS).MethodsThis was a prospective cross-sectional survey among men who presented with benign prostatic hypertrophy to the urology clinic of the Ekiti State University Teaching Hospital, Ado -Ekiti with LUTS between January 1 and December 31, 2014. One hundred and forty men who presented in the urologic clinic with LUTS were recruited. PSA was analyzed using standard method while other clinical variables were collected using a clinical case form. Multivariate logistic regression was used to estimate the odds of an abnormal PSA of ≥4.0 ng/mL or ≥10.0 ng/mL in these men.ResultsThe mean ages of obese and non-obese men were 64.8 and 64.0 years respectively. The mean total serum PSA were 14.8 and 13.2 ng/mL for obese and non-obese men respectively. Univariate analysis showed no difference (p > 0.05) in the proportion of obese and non-obese men with LUTS who had a PSA threshold of at least 4.0 ng/mL. Multivariate logistic regression showed that, at a PSA threshold of 10.0 ng/mL, obese men had a statistically significant proportion (p < 0.05). Although not significant, non-obese patients were less likely to have PSA level of ≥4.0 ng/mL (OR 0.701; 95% CI 0.301–1.630) compared to obese men. In the same vein, non-obese men were less likely to have a PSA level of 10.0 ng/mL (OR, 0.686; 95% CI, 0.318–1.478) in a simultaneous context of age.ConclusionOur study demonstrated that, in a sample population of predominantly native African men, there was a non-significantly higher likelihood of overweight/obese patients having a higher serum PSA level than the non-obese. A community based study is needed to further confirm this finding

Policy Responses to Addressing the Issues of Environmental Health Impacts of Charcoal Factory in Nigeria: Necessity Today; Essentiality Tomorrow

Worldwide trebled of wood charcoal production over the last 50 years from 17.3 million tons in 1964 to 53.1 million tons in 2014 with sixty-one percent of current global production occurring in Africa, primarily to satisfy the demand for cooking fuel from urban and rural households with 2.7 billion people relying on wood fuels in the global south, while, the rural populace in Nigeria use about 80 million cubic meters of wood fuel annually for household energy. The furnaces of the world are now burning about 2, 000, 000, 000 tons of charcoal a year. When this is burned, uniting with oxygen, it adds about 7, 000, 000, 000 tons of carbon dioxide to the atmosphere yearly. This tends to make the air a more effective blanket for the earth and to raise its temperature. The effect may be considerable in a few countries. With Nigeria’s population projected to hit 410.6 million by 2050 and 550million by 2070 and consequently, becoming the third most populous country on our planet, and with an increased population growth rate in this part of the global village is alarming and worrisome, couple with rural-urban migration in key producing states, including Kwara, Ogun, Osun, Ondo, Ekiti, Kogi, etc. Whilst demand for charcoal is projected to increase in Nigeria, the availability of woody biomass is declining due to widespread net deforestation and biomass being the only energy source of choice due to large scale poverty and unaffordable prices of other alternatives like gas and electricity. While the human population naturally increases geometrically, the power of the improvements in resources goes up arithmetically leading to disequilibrium. This disequilibrium promotes a lot of crises bordering on economy, security, health, and politics among others. It is a fact that human populations tend to increase much more rapidly than the means of subsistence. Given the increasing demand for charcoal, and decreasing availability of biomass, policies are urgently needed that ensure secure energy supplies for urban and rural households and reduce deforestation. There is potential for charcoal to be produced sustainably in natural woodlands, but this requires supportive policies, economic diversification, and investment in improved eco-stoves. New advocacy and public health movement are needed urgently to bring together governments, international agencies, development partners, communities, and academics from all disciplines to address the effects of charcoal factories on health

Exposure to known COVID-19 infection risk factors among healthcare workers responding to COVID-19 outbreak in Lagos State, Nigeria-2020

Introduction: Globally, over 790,000 deaths of COVID-19 cases were reported by August 20, 2020, these numbers included healthcare workers (HCW). The high infection rate among HCW to COVID-19 is worrisome requiring countries to protect them. We examined the risk of exposure among HCW. Methods: We conducted a cross-sectional study among 151 healthcare workers responding to the COVID-19 outbreak in Lagos State using an electronic-based self-administered questionnaire. Categorical variables were summarized as proportions, and bivariate analysis of the independent and dependent variables was subjected to the Chi-square test. A P-value of &lt; 0.05 was considered statistically significant. Results: Sixty-nine (45.9%) of responders have had over 10-year experience in the health sector. Ninety-eight (64.9%) of the responders had previous experience in responding to outbreaks. Ninety-nine (65.6%) of responders had been involved in the COVID-19 response beyond two months. Sixty-three (41.7%) participants were exposed to aerosol-generating procedures (AGP), with the majority (85%) occurring during the collection of sputum for COVID-19 testing. Forty-three percent were involved directly with facilities where confirmed cases were treated. Among responders, 101 (66.9%) admitted to the regular use of work-appropriate personal protective equipment (PPE) during their activities. One hundred and thirty-seven HCW (90.7%) had no exposure to biological or respiratory fluids. On bivariate analysis, no variable was associated with the risk of contracting the infection by healthcare workers. Conclusion: The exposure to known COVID-19 risk factors among healthcare responders in Lagos is high. This exposure is not associated with years of experience of service in the health sector, age or gender of responders, direct contact with confirmed cases, or direct care of confirmed COVID-19 cases

Tumours and tumour-like lesions of the lower face at Korle Bu Teaching Hospital, Ghana – an eight year study

<p>Abstract</p> <p>Background</p> <p>The oro-facial region including the jawbones, the maxilla and mandible and related tissues can be the site of a multitude of neoplastic conditions. These tumours have a predilection for the entire facial region; however, odontogenic tumours tend to affect the mandible more than the maxilla, especially, in West African children. We report results from a retrospective study spanning eight years on the frequency, clinical presentation, sites and character of lower face tumours seen in the main referral hospital in Ghana.</p> <p>Patients and methods</p> <p>Records of consecutive patients of all age and sex seen by the first author's team at the Department of Oral and Maxillofacial Surgery, Korle-Bu Teaching Hospital with tumours affecting the lower part of the face from January 1996 to December 2003 were retrieved, coded and entered into a database. The data were then analyzed by age, sex, presenting signs and symptoms, site of lesion, and their histology.</p> <p>Results</p> <p>A total of 394 patients with oro-facial swellings were retrieved from the registry out of which 210 had lower face tumour and tumour-like lesions. The complete data set was obtained for 171 patients, comprising 99 (58%) males and 72 (42%) females. The most common clinical presenting features were mandibular facial swelling (63%), intra-oral swelling (55%), pain (41%) and ulceration (29%). The tumours were predominantly found in the right (43%), anterior (19%) and left (18%) aspects of the lower face. The remainder making up 20% were found in the floor of the mouth, tongue and lips. Seventy eight (45.6%) of the patients presented with lesions that were classified as malignant of which 54 (62%) were diagnosed as squamous cell carcinoma (SCC). Sixty-two (36.3%) had benign odontogenic tumours and thirty-one (18.1%) had non-odontogenic tumour-like lesions. Fifty-four (62%) of malignant tumours were squamous cell carcinoma; 58 (93.6%) of the benign odontogenic tumours were classified as ameloblastoma. The mean age at presentation of all lesions was 40.4 years with over 50% of benign lesions in patients aged between 11 and 30 years. Malignant tumours were more commonly detected in patients between 41 and 70 years (63%).</p> <p>Conclusion</p> <p>Tumours and tumour-like lesions of the lower face comprising the mandible, tongue and adjacent structures are a diverse group of neoplasm and are seen commonly in practice of Maxillofacial surgery. Both malignant and benign tumours are seen in the Ghanaian population. In the present study, SCC and ameloblastoma were the commonest malignant and benign odontogenic tumours seen respectively; the two representing more than 65% of all tumours.</p

UCP-LF and other assay methods for schistosome circulating anodic antigen between 1978 and 2022

Detection of circulating anodic antigen (CAA) is known for its high sensitivity in diagnosing schistosomiasis infection, even in low-prevalence settings. The Up-Converting Phosphor-Lateral Flow (UCP-LF) assay developed in 2008 presented greater sensitivity than other assay methods in use for CAA detection. Our study aims to comprehensively review all studies conducted in this area and thus generate informed conclusions on the potential for adopting the UCP-LF assay for diagnosing this important yet neglected tropical disease. Using the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines, we generated search criteria to capture all studies in English journals available in the Scopus and PubMed databases on 20 December 2022. A total of 219 articles were identified, and 84 that met the inclusion criteria were retrieved and eventually included in the study. Twelve different assay methods were identified with a noteworthy transition from enzyme-linked immunosorbent assay (ELISA) to the UCP-LF assay, a laboratory-based assay that may be applicable as a point-of-care (POC) diagnostic test for schistosomiasis. Reducing the time, cost, and dependence on specialized laboratory skills and equipment, especially relating to the trichloroacetic acid extraction step and centrifugation in the UCP-LF CAA assay may go a long way to aid its potential as a POC tool. We also propose the development of a CAA-specific aptamer (short protein/antigen-binding oligonucleotide) as a possible alternative to monoclonal antibodies in the assay. UCP-LF has great potential for POC application