Transition of hemoglobin between two tertiary conformations: The transition constant differs significantly for the major and minor hemoglobins of the Japanese quail (Cortunix cortunix japonica)

We demonstrate that 5,5′-dithiobis(2-nitrobenzoate) – DTNB – reacts with only CysF9[93]β and CysB5[23]β among the multiple sulfhydryl groups of the major and minor hemoglobins of the Japanese quail (Cortunix cortunix japonica). Kequ, the equilibrium constant for the reaction, does not differ very significantly between the two hemoglobins. It decreases 430-fold between pH≈5.6 and pH≈9: from a mean of 7±1 to a mean of 0.016±0.003. Quantitative analyses of the Kequ data based on published X-ray and temperature-jump evidence for a tertiary structure transition in liganded hemoglobin enable the calculation of Krt, the equilibrium constant for the r←→t tertiary structure transition. Krt differs significantly between the two hemoglobins: 0.744±0.04 for the major, 0.401±0.01 for the minor hemoglobin. The mean pKas of the two groups whose ionizations are coupled to the DTNB reaction are about the same as previously reported for mammalian hemoglobins

Effect of cold temperature storage on the quality attributes of pawpaw and guava leathers

The effect of cold temperature storage on the quality attributes of pawpaw and guava leathers was evaluated. Pawpaw leather was significantly higher than guava leather in calorific content, water activity, pH and total mould count throughout the duration of storage. However Guava leather was higher in texture. Sensory scores in relation to period of storage showed that Guava leather gave better result in overall acceptability at zero, one and two months of storage at 8 ± 10C. Guava leather also gave better sensory qualities in fruitiness, smell, chewiness, toughness, colour, and overall acceptability when varietal influence is considered. Guava leather is better accepted. (African Journal of Biotechnology: 2002 1(2): 61-63

Dynamic Performance Analysis of Cogeneration Potential in Photovoltaic Power System.

The solar cell junction is susceptible to performance degradation, due to internal temperature rise which is further perturbed by ambient temperature rise. The conversion efficiency of the solar module remarkably drops because of temperature rise. The diurnal module temperature hovers above 60 degrees C. It is possible to keep the conversion efficiency high by water-cooled or air blast equipment. This project is a preliminary study of the impact of temperature variation across seasons on the dynamic performance of photovoltaic power system. The photovoltaic (PV) module was mounted on a test rig at latitude 7 degree on top of physics building Obafemi Awolowo University campus. The output voltage of the PV module was applied to a resistive load and system efficiency performance measured over a period of time covering the dry and rainy seasons. Measurements of ambient temperature, PV junction operating temperature, wind speed, solar irradiance, and power delivered were carried out. A numerical algorithm was developed to analyse the data. The transport medium can store heat energy from the solar module, so that a large amount of hot water can be produced. The results show that this thermal transfer benefit, positions the PV system in good stead, for Microgrid: Cogeneration Energy Efficiency functionality. Keywords: Conversion efficiency, Photovoltaic power system, PV module, Water-cooled equipment, Cogeneration

Photovoltaic Generating System Parameter Sizing for Building

Small to medium sized battery storage required to address the intermittency challenge of the energy of solar radiation could be achieved by appropriate sizing of the photovoltaic system parameters like photovoltaic module (PVM) number and battery capacity. This paper presents the results of evaluation of the optimum parameter values in sizing of stand-alone photovoltaic (PV) system that satisfies building energy demand, with almost zero Loss of Power Supply Probability (LPSP). A time step simulation of system performance based on energy balance for various combinations of PV numbers and battery capacities was employed. (Three seasons of operation were considered; rainy, hot and hot/dry). The rainy season result indicating high storage capacity requirement of about (2500-Ah), is of highest cost compared to other seasons. Stand-alone photovoltaic system size that will assuage the intermittency challenge; mitigate peak demand costs and provide near zero LPSP was determined. Keywords: loss of power supply probability, photovoltaic, energy demand, parameter sizing, stand-alon

Ethno-religious voting in Nigeria: interrogating voting patterns in the 2019 presidential election

This article analyses voting patterns in Nigeria’s 2019 presidential election. Its main objective is to gauge continuity or change in ethnic, regional and religious voting in Nigeria’s elections. The paper takes a historical approach in examining voting patterns in the past elections as a background to the examination of the 2019 presidential election. It was discovered that ethnic, regional and religious sentiments were still major factors that shaped voting choice in the election

Incentive Package, Employee’s Productivity and Performance of Real Estate Firms in Nigeria

The level of motivation received by an employee as reflected in the satisfaction with the base pay package and other incentives goes a long way to influencing the employees’ attitude to work, loyalty, performance and job satisfaction. Employee’s motivation and organization performance has been investigated across different fields and economic sectors. This study takes it further by examining incentive package, employees and organization productivity in real estate firms in Nigeria. Panel survey approach was adopted and three questionnaires administered in each of the one hundred and seventeen (117) estate firms in Ikeja, Victoria Island and Lekki Area of Lagos State. Respondents were two employees and one other in employers’/management capacity. Descriptive tools such as frequency and percentage were used to identify and determine the proportion of firms that make use of incentive package/option while a 5-point Likert scale and ranking were used to determine and rank the options in order of importance among these firms. Panel data regression model was used to determine the strength of relationship between firms’ performance/productivity and incentives whilst holding other factors constant. Findings showed amongst others that there is strong positive correlation between incentive and employee productivity, employees are largely dissatisfied with the incentives offered by majority of estate firms and that incentive package is not the most important determinants of performance in real estate firms. The study therefore concludes that employers in real estate firms pay attention to other factors identified and review remuneration and incentive package to boost the morale of their employees for better performance

Aluminum Silicon Carbide Particulate Metal Matrix Composite Development Via Stir Casting Processing

In this paper, conventional simple methods of producing MMC with attained properties through the dispersion of silicon carbide in the matrix are investigated. To achieve these objectives a two-step mixing method of stir casting technique was employed. Aluminum (99.66 %C.P) and SiC (320 and 1200 grits) were chosen as matrix and reinforcement materials respectively. Experiments were conducted by varying the weight fraction of SiC for 2.5 %, 5.0 %. 7.5 % and 10 %. The result indicated that the st ir casting method was quite successful to obtain uniform dispersion of reinforcement in the matrix. This was evident by the improvement of properties of composites over the base metal. Reinforced Aluminum Silicon Carbide (ASC) showed an increase in Young's modulus (E) and hardness above the unreinforced case and marginal reduction of electrical conductivity was recorded for the composites. The silicon carbide of 1200gnts (3 J.lm) showed increased Young's modulus (E) and hardness of 15 17.6 Mpa and 26.1Hv values at 7.5% volume fraction silicon carbide; when compared with the silicon carbide 320 grit (29 J.lm). Also; the electrical conductivity properties of the two grit sizes of the silicon carbides were less than the base metal for all the volume fractions of silicon carbide

Crystalline Maculopathy: A Report of Two Patients in Ibadan, Southwestern Nigeria

We present two patients with crystalline maculopathy seen at the Eye Clinic of the University College Hospital, Ibadan, Nigeria. Both patients had diabetes, with the first patient having systemic hypertension controlled on medications. There was no history of kola nut ingestion in the two patients. Medical examination by the internist revealed no other systemic disease. The central vision was good in both patients. Optical coherence tomography localized the crystals to the inner retina, and there was no associated macular edema. Some pathogenetic mechanisms are proffered based on available literature

Aluminum Silicon Carbide Particulate Metal Matrix Composite Development Via Stir Casting Processing

In this paper, conventional simple methods of Q1 producing MMC with attained properties through the dis persion of silicon carbide in the matrix were investi11 gated. To achieve these objectives two step-mixing method of stir casting technique has been employed. Aluminum (99.66 %C.P) and SiC (320 and 1200 grits) were chosen as matrix and reinforcement materials respectively. Exper iments were conducted by varying weight fraction of SiC for 2.5 %, 5.0 %, 7.5 % and 10 %. The result indicated that the stir casting method was quite successful to obtain uniform dispersion of reinforcement in the matrix. This was evident by the improvement properties of composites over the base metal. Reinforced Aluminium Silicon Car bide (ASC) showed increase in Young’s Modulus (E) and hardness above the unreinforced case and marginal reduc tion of electrical conductivity was recorded for the com posites. The silicon carbide of 1200 grits (3 μm) showed increased Young’sModulus (E) and hardness of 1517.6Mpa and 26.1 Hv values at 7.5% volume fraction silicon carbidewhen compared with the silicon carbide 320 grit (29 μm)Also; the electrical conductivity properties of the two grit sizes of the Silicon Carbides were less than the base metal for all the volume fraction of Silicon Carbid

Incessant Building Collapse in Nigeria: A Framework for Post-Development Management Control

This study investigates post-development management approach of properties and how it could be improved to stem the tide of building collapse in Nigeria. Extant literatures were reviewed and primary data collected with the use of structured questionnaires administered on occupants of one hundred and fifty residential and seventy-five commercial properties across Lagos State, Nigeria. Data was analysed with basic descriptive tools such as frequency, percentage, Likert scale and weighted mean score. Findings reveal abuse of property management functions by property owners and non-professionals alike in the management of various properties. Findings also show a high level of dissatisfaction with the services provided mostly by the non-professionals and that integrity assessment is rarely carried out by the professionals and non-professionals alike. The study therefore recommends that post development property management services become an exclusive preserve of professional property managers. The study further recommends that properties must be subjected to mandatory integrity assessment and subsequently, recommended for similar exercise based on the report of routine management inspection. The proposed framework for carrying out the structural integrity assessment and appropriate recommendations for the outcome of routine inspection or integrity assessment is a key contribution of this study to existing literatures on building collapse in the country. Keywords: Building collapse, Post-Development, Property Management, Framework, Structural Integrit