Energy-Efficient Construction in Nigeria: The Adoption of Expanded Polystyrene Wall Panels in Abuja Metropolis

In recent times, Abuja, the Federal capital city of Nigeria has witnessed an extensive use of innovative building materials including Expanded Polystyrene (EPS) in housing delivery. This is in the quest to develop alternative local building materials to the conventional sandcrete blocks, which is of increasing high cost and import dependent. This paper therefore, reports a comparative study on the use of EPS materials over the sandcrete blocks in masonry works in FCT, Abuja. Data for the research were obtained through interview schedules and observations from five (5) selected case studies of housing projects built with EPS panels in Abuja and compared with other housing projects constructed with sandcrete blocks with the aim ascertaining the comparative advantages of EPS panels over the conventional walling materials. Over one hundred and twenty (120) building professionals (Architects, Engineers, Builders and Quantity Surveyors) involved in the construction of these projects were interviewed. Analyses of the findings indicate that EPS buildings demonstrate high thermal insulation capacity, light weight, faster time, higher strength, greater structural stability and cost effectiveness. The paper concludes that EPS panels are better alternatives to the conventional sandcrete blocks and should be used in place of the former in housing delivery in Nigeria. Keywords: Abuja, building materials, expanded polystyrene, urban housin

Periodicity, Stability, and Boundedness of Solutions to Certain Second Order Delay Differential Equations

The behaviour of solutions to certain second order nonlinear delay differential equations with variable deviating arguments is discussed. The main procedure lies in the properties of a complete Lyapunov functional which is used to obtain suitable criteria to guarantee existence of unique solutions that are periodic, uniformly asymptotically stable, and uniformly ultimately bounded. Obtained results are new and also complement related ones that have appeared in the literature. Moreover, examples are given to illustrate the feasibility and correctness of the main results

Sustainable Construction: Comparative Advantages of Expanded Polystyrene (EPS) Fascia in Housing Delivery in Nigeria

Various environmental challenges posed by the application of non-sustainable construction materials and techniques and higher cost of same in the recent time have made the search for better and cheaper alternatives a crucial task in the provision of housing in Nigeria. As a product of research and technological advancements, modern eco-friendly building materials are currently emerging to satisfy the requirements of sustainable developments and mitigate environmental challenges. One of such materials is the expanded polystyrene or EPS. This paper focuses on sustainable construction with emphasis on the comparative advantages of expanded polystyrene fascia over the conventional concrete fascia in the delivery of housing in Nigeria. The data for the research were obtained through primary sources of data gathering. This involves primary stage of purposeful selection from two cities namely Abuja and Akure, Nigeria, where the material (EPS) was extensively used in housing estates. Analysis of the findings from the two housing estates selected as case studies, reveal that EPS fascia demonstrates faster construction time, flexibility of design, lesser number of labor to be engaged, higher strength, cheaper cost and higher sustainability potentials over the conventional concrete fascia used for similar housing units in same locations. While it was discovered that there is little or no availability of the material in most Nigerian building markets due to lack of awareness among the various stakeholders and practitioners in the building industry, it x-rayed the need for a paradigm shift from the conventional system of building characterized by waste, cradle to grave (demolition) and global warming to a waste-free, recyclable, eco-friendly and cheaper alternative way of building construction. Keywords: Concrete fascia, Expanded Polystyrene (EPS) fascia, Green architecture, Housing, Sustainable construction

Primary osteogenic sarcoma of the breast

BACKGROUND: Primary extra-osseous osteogenic sarcomas have been reported in many tissues of the body but their occurrence in the breast is extremely rare. It can arise as a result of osseous metaplasia in a pre-existing benign or malignant neoplasm of the breast or as non-phylloides sarcoma from the soft tissue of a previously normal breast. CASE PRESENTATION: A 40 year-old Nigerian woman was clinically diagnosed to have carcinoma of the left breast. The histology report of core-needle biopsy of the mass showed a malignant neoplasm comprising islands of chondroblastic and osteoblastic stromal cells. This report changed the diagnosis from carcinoma to osteogenic sarcoma of the breast. She had a left modified radical mastectomy, however there was significant post surgery skin deficit. A latissimus dorsi musculocutaneous flap was used to cover the anterior chest wall defect. Sections from the mastectomy specimen confirmed the diagnosis of osteogenic sarcoma. She died six months after mastectomy. CONCLUSION: A diagnosis of osteogenic sarcoma of the breast was made based on histology report and after excluding an osteogenic sarcoma arising from underlying ribs and sternum. This is the second documented case of primary osteogenic sarcoma of the breast coming from Nigeri

ON STABILITY OF QUANTUM STOCHASTIC DIFFERENTIAL EQUATION

The long run behaviour of solutions of Lipschitzian quantum stochastic differential equation (QSDE) with non-instantaneous impulse is studied. This is achieved by imposing some conditions on the coefficients associated with the map P. Using the fixed point approach, we show that a solution exists under the given conditions and subsequently establish Ulam's type stability. We present some examples to further justify its application

Stability, Boundedness, and Existence of Periodic Solutions to Certain Third-Order Delay Differential Equations with Multiple Deviating Arguments

The behaviour of solutions for certain third-order nonlinear differential equations with multiple deviating arguments is considered. By employing Lyapunov’s second method, a complete Lyapunov functional is constructed and used to establish sufficient conditions that guarantee existence of unique solutions that are periodic, uniformly asymptotically stable, and uniformly ultimately bounded. Obtained results not only are new but also include many outstanding results in the literature. Finally, the correctness and effectiveness of the results are justified with examples

Cross-ancestry GWAS meta-analysis identifies six breast cancer loci in African and European ancestry women

Our study describes breast cancer risk loci using a cross-ancestry GWAS approach. We first identify variants that are associated with breast cancer at P \u3c 0.05 from African ancestry GWAS meta-analysis (9241 cases and 10193 controls), then meta-analyze with European ancestry GWAS data (122977 cases and 105974 controls) from the Breast Cancer Association Consortium. The approach identifies four loci for overall breast cancer risk [1p13.3, 5q31.1, 15q24 (two independent signals), and 15q26.3] and two loci for estrogen receptor-negative disease (1q41 and 7q11.23) at genome-wide significance. Four of the index single nucleotide polymorphisms (SNPs) lie within introns of genes (KCNK2, C5orf56, SCAMP2, and SIN3A) and the other index SNPs are located close to GSTM4, AMPD2, CASTOR2, and RP11-168G16.2. Here we present risk loci with consistent direction of associations in African and European descendants. The study suggests that replication across multiple ancestry populations can help improve the understanding of breast cancer genetics and identify causal variants

Parity and breastfeeding are protective against breast cancer in Nigerian women

As the relation between reproductive factors and breast cancer risk has not been systematically studied in indigenous women of sub-Saharan Africa, we examined this in a case–control study in Nigeria. In-person interviews were conducted using structured questionnaires to collect detailed reproductive history in 819 breast cancer cases and 569 community controls between 1998 and 2006. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CI). Compared with women with menarcheal age <17 years, the adjusted OR for women with menarcheal age ⩾17 years was 0.72 (95% CI: 0.54–0.95, P=0.02). Parity was negatively associated with risk (P-trend=0.02) but age at first live birth was not significant (P=0.16). Importantly, breast cancer risk decreased by 7% for every 12 months of breastfeeding (P-trend=0.005). It is worth noting that the distribution of reproductive risk factors changed significantly from early to late birth cohorts in the direction of increasing breast cancer incidence. Our findings also highlight the heterogeneity of breast cancer aetiology across populations, and indicate the need for further studies among indigenous sub-Saharan women