262 research outputs found
Transition of hemoglobin between two tertiary conformations: Determination of equilibrium and thermodynamic parameters from the reaction of 5,5′-dithiobis(2-nitrobenzoate) with the CysF9[93]β sulfhydryl group
The equilibrium constant of the reaction of 5,5′-dithiobis(2-nitrobenzoate) with the CysF9[93]β sulfhydryl group of hemoglobin decreases by
2 to 3 orders of magnitude between pH 5.6 and 9. The reaction is coupled to the ionizations of two groups on the protein. At 25 °C one group has a pKa of 5.31±0.2 when hemoglobin is in its (tertiary) r conformation, typified by the thiolate anion form of CysF9[93]β; this changes to 7.73±0.4 in the (tertiary) t conformation, typified by the mixed disulfide form of the sulfhydryl. The second group ionizes with a pKa of 7.11±0.4 in the r conformation; this changes to 8.38±0.2 in the t conformation. Krt, the equilibrium constant for the r←→t isomerization process, is 0.22±0.06.
The standard enthalpy and entropy changes for the isomerization are ΔHo rt=24.2 kJ mol−1 and ΔSo
rt=68.8 JK−1mol−1, respectively
Groundwater Geogenic and Anthropogenic Assessment of Organic and Inorganic Contaminants within Three Major Metropolies in Enugu
This study assessed the impact of increased industrialization and population within three major metropolis in Enugu, namely Abakpa, Emena, and Independence Layout by analyzing 60 water samples and 10 shale samples. Inventory of Dumpsites were done and categorized into domestic, industrial, commercial and hazardous wastes. Pollution load indices analysis such as Heavy metal pollution index (HPI), Heavy metal evaluation index (HEI) and Degree of contamination (Cdeg) categorized the groundwater quality in the study area into low, intermediate and high contamination. The multivariate statistical analysis extracted three anthropogenic diagnostic factors controlling the chemistry based on the parameter associations. The XRD analysis shows that influence of geogenic factors in groundwater contamination within the study area is very minimal. None of the computed WQI fell within the excellent water quality within the stud. Generally 28.3% of the groundwater fell under the good water quality, 41.6% within the poor water quality, 20% within the very poor water quality and 10% within the unsuitable water condition. DOI: 10.7176/JEES/13-4-04 Publication date:June 30th 2023
Design and Implementation of a Mobile Express Delivery System
Express delivery services in the world today have advanced greatly in developed
countries with the use of information and communication technology (ICT) product and services.
Meanwhile, most courier companies particularly the indigenous ones in the developing countries
including Nigeria still have many problems in the delivery chain of courier services operations. The
existing express delivery system lack mobile facilities for customers to lodge complains and track
shipment on the move and courier agents are not able to access courier information while on the
field. This paper presents the design and implementation of a Mobile Express Delivery System
(EDS) on a WAP-enabled platform to enable courier customers perform various operations via
mobile device such as tracking of shipment, checking account statement and lodging complaints.
The Mobile EDS provides the courier customers a means of tracing/tracking shipment, lodging of
complaints and making financial transactions on shipment. It also assists the courier staff to
effectively manage courier related data with a mobile phone. The system is therefore able to
enhance time, efficiency and documentation management for the customer and courier staff
Impact of Social Entrepreneurship on Youth Economic Empowerment in Kaduna Meropolis, Kaduna-Nigeria
There are certain kinds of people who garner enormous satisfaction from successfully taking on a “mission impossible” and, by so doing, actually manage to change the world, or wherever they live, sometimes in surprising ways. Such individuals are rare, and when we become aware of them and their astonishing achievements, we observe that they cannot easily be ignored. Such individuals are the products of rural as well as urban areas; of developing as well as developed countries; of large cities as well as remote areas; they may be Hausas/Fulanis from Northern Nigeria, or Yorubas from the South-Western Nigeria, or Igbos from the Souh-Eastern Nigeria, or other tribes like the Tivs, Gwaris and Nupes from north-entral Nigeria, Kanuris from the northeastern Nigeria. They may be well- known figures, such as Gen. Ibrahim Badamasi Babangida, Gen. TY Danjuma, Gen. Aliyu Mohammed Gusau, Alhaji Atiku Abubakar (Wazirin Adamawa), Alhaji Aminu Dantata, Alhaji Aliko Dangote, or anonymous, unrecognized individuals from cities and small villages in Nigeria and elsewhere. Social entrepreneurship has emerged as a contemporary issue in the social arena. It is a concept well suited for our age because it makes a call for entrepreneurial activities to spearhead the resolving of social issues in our communities; since many governmental and charitable efforts have failed to meet the existing social needs (Dees, 2001). Societies are dealing with social challenges such as youth unemployment, poverty, hunger, terrorism, floods, health care challenges, infrastructural inadequacies, and maternal mortality, among others. All these challenges are capable of affecting the social wellbeing of individuals. Life can only be interesting if there are tools and strategies readily available for dealing with these challenges. Social challenges at different levels (global, national or regional) require special strategies and tools for handling them. The complexities of social challenges experienced in most parts of Nigeria, especially Kaduna metropolis demands a more creative and innovative approach in balancing these pressures and constraints geared towards overcoming these challenges as well as initializing sustainable development in our communities
Characteristic trace fossils from Miocene brackish- water deposits in the Niger Delta, Nigeria
Miocene deposits in the eastern portion of the Greater Ughelli, Central Swamp and Coastal Swamp depobelts contain well-developed brackish-water trace fossil assemblages. Twelve ichnogenera have been identified, namely: Asterosoma, Bergaueria, Chondrites, Gyrolithes, Thalassinoides, Lockeia, Palaeophycus, ?Conichnus, Planolites, Siphonichnus, Skolithos and
Diplocraterion. In addition, common non-descript, passively filled burrows and fugichnia (escape structures) have also been observed. The above-mentioned ichnogenera and associated non-descript structures can be arranged into six distinct and recurring ichnoassociations within the Greater Ughelli, Central Swamp and Coastal Swamp depobelts. Each ichnoassociation is comprised of a group of trace fossils which collectively reflect specific environmental conditions during deposition of these Miocene strata. All trace fossil assemblages illustrate deposition in nearshore, restricted settings. Ichnological and sedimentological criteria which may be utilized to recognise brackish-water deposits are discussed and illustrated in pictures of the cores studied
MEASURING ORGANIZATIONAL CITIZENSHIP BEHAVIOR OF LECTURERS: THE ROLE OF PERSONALITY AND LOCUS OF CONTROL
This study examined the influence of personality and work-locus of control on lecturers’ organizational citizenship behaviour. A total of 204 participants (75 females and 129 males) selected through simple random sampling technique were drawn from Federal Polytechnics Oko Anambra State, Nigeria as participants of the study. Their ages ranged from 27 to 67 years with a mean age of 49.43 years and a standard deviation of 9.82. A cross sectional survey design was employed for the study while two-way Analysis of variance statistic was used for data analysis. The result revealed a significant main effect for personality at F (4,194) = 4.15, p < .05. Extraverted lecturers had more tendencies to practice OCB than open to new experience and agreeable lecturers, as well as conscientious lecturers. However, no significant influence for work locus of control (M=1,194) = 0.67>.05 with the internal locus of control participants (m =121.05, SD = 32.77), was observed on tendency to practice OCB than their external (M. 121. 64, SD = 25.41) counterparts. Also, the result showed no significant interaction effect between personality factors and work-locus of control on lecturers’ citizenship behaviour, F (4, 194) =1.08 AT p<.05. It recommended that Nigerian tertiary institutions use psychometric evaluation in lecturers’ selection process in order to take advantage of those more likely to exhibit citizenship behaviour. Article visualizations
Mineralogical and Geochemical Assessment of Clay Properties of Edda, Afikpo Sub Basin Nigeria for Possible Use in the Ceramics Industry
Clay samples from selected part of Edda were analyzed to identify the clay mineral types present, their chemical and physical properties with a view to appraising their industrial suitability as ceramic materials. The mineralogical and geochemical analyses were done using the principles of X-Ray diffraction and X-ray fluorescence respectively. A total of seven clay samples were used for the study, other tests such as plasticity, bulk density, shrinkage, loss on ignition (LOI) and water absorption capacity was carried out to determine the amount of water absorbed under specified conditions. The basic industrial properties assessment showed that more than 70% of the clays are fine-grained. The clays exhibited low to moderate plasticity, moderate shrinkage and bulk density, low to moderate values of both loss on ignition and water absorption capacity. The clays are buff to yellowish in colour. The results of x-ray fluorescence revealed that the mean concentration of major oxide in the clays is shown as follows: SiO2 (62.78%), Al2O3 (20.25%), total Fe (6.09%), CaO (0.56%), MgO (3.21%),Na2O (0.47%), K2O, (1.44%) and TiO2 (0.52%).The samples have high silica content, low alumina and low oxide content. The results of x-ray diffraction revealed that kaolinite is the dominant clay mineral with illite and montmorillonite occurring in subordinate amounts, while quartz and feldspar are the non-clay components present. The characteristics of the clays for each parameter were compared with industrial standards.These properties are appropriate for the Afikpo clays to be useful in the manufacturing of ceramics. However, since the silica content of the clays is high further beneficiation is recommended
THEORETICAL CORRELATION OF AGEING, MENTAL ACTIVITY AND MEMORY RECALL: IMPLICATION FOR SECURITY PERSONNEL
This study explored theoretical correlation of ageing, mental activity and memory recall and its implication for security personnel. Ebbinghaus’ experiment with the list of nonsense syllables in 1885 has created the awareness that a lot factors can influence brain behaviour; critically ageing and mental activity. Despite the abundance of empirical literature on varying experiments to expose the correlation of brain behaviour and other human behavioural outcomes, the need to establish theoretical basis for understanding these relationships becomes important. Using Two-Stage Process theory of memory recall by Watkins and Gardiner (1979) which emphasized search and retrieval process; and Encoding Specificity theory by Tulving and Donald (1973) which emphasized encoding conditions and conditions at the time of retrieval, memory recall process was reviewed as brain behaviour in the light of how ageing and mental activity (cognitive exercise) may influence it. Given the found theoretical linkage, it is recommended that positive valences which improve mental wellbeing and varying brain behavior be encouraged in the workplace to improve the quality of human output in the organization. Article visualizations
Under-5 mortality and its associated factors in Northern Nigeria : evidence from 22,455 singleton live births (2013-2018)
The northern geopolitical zones (NGZs) continue to report the highest under-5 mortality rates (U5MRs) among Nigeria’s six geopolitical zones. This study was designed to identify factors related to under-5 mortality (U5M) in the NGZs. The NGZ populations extracted from the 2018 Nigeria Demographic and Health Survey were explored to assess the factors associated with U5M using logistic regression, generalised linear latent, and mixed models. Between 2013 and 2018,
the northwest geopolitical zone reported the highest U5MR (179 deaths per 1000 live births; 95% confidence interval [CI]: 163–194). The adjusted model showed that geopolitical zone, poor household, paternal occupation, perceived children’s body size at birth, caesarean delivery, and mothers and fathers’ education were highly associated with increased odds of U5M. Other significant factors that influenced U5M included children of fourth or higher birth order with shorter interval ≤ 2 years (adjusted odds ratio [aOR] = 1.68; CI: 1.42–1.90) and mothers who did not use contraceptives (aOR = 1.41, CI: 1.13–1.70). Interventions are needed and should primarily spotlight children residing
in low-socioeconomic households. Educating mothers on the benefits of contraceptive use, child spacing, timely and safe caesarean delivery and adequate care for small-sized babies may also reduce U5M in Nigeria, particularly in the NGZs
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