Background: Children with sickle cell disease (SCD) are frequently evaluated for spleen involvement using laboratory markers and subjective ultrasound interpretation. Quantitative ultrasound echotexture analysis could offer an objective way to assess spleen parenchymal alterations. Although its relationship with hematological markers of spleen function is not well established. Aim: The study assessed the relationship between selected hematological parameters and quantitative ultrasonography spleen parenchymal echotexture in children with sickle cell disease. Methods: In this cross-sectional study, children with SCD underwent standardized B-mode ultrasound scan of the spleen. Quantitative echotexture measures, including mean pixel intensity (MPI), were extracted from defined regions of interest using a validated MATLAB algorithm. Hematological parameters; white blood cell (WBC) count, red blood cell (RBC) count, and platelet count were obtained on the same day. Pearson correlation coefficients were used for analysis. Results: Mean Pixel Intensity showed a statistically significant moderate positive correlation with WBC count (r = 0.53, p = 0.002). Correlations between MPI and RBC count (r = 0.09, p = 0.58), platelet count (r = 0.18, p = 0.27) were weak and not statistically significant. Conclusion: Quantitative spleen echotexture, assessed via pixel intensity analysis, is meaningfully associated with WBC count in children with SCD. Mean pixel intensity may serve as a promising non-invasive imaging biomarker, complementing hematological assessment and enhancing the objectivity of spleen ultrasound evaluation.

The dielectric and mechanical properties of montmorillonite clay/polyester nanocomposite at various filler loadings were investigated. Five different samples of the nanocomposite were produced using melt interclation method while varying the percentage composition of montmorillonite clay from 5wt% to 25wt%. The tensile, compressive, and flexural strengths and impact energy on five replicate specimens for each test were analysed. Also the capacitance and dielectric strength of the samples were evaluated. Results obtained showed that whereas a drastic decrease in the impact energy of >100% was observed, the maximum tensile strength and Young’s modulus values of 50.27MPa and 8.76GPa respectively were obtained at 10% filler loading. Also the flexural and compressive strengths increased by 48% and 100% at 15wt% and 20wt% filler loading respectively. There was also an increase in capacitance (32%) and dielectric strength (>100%) of the samples with each filler addition up to 25% with 3 times increase in hardness at 25wt% as well.

Malaria is considered an important cause of morbidity and mortality among people living with sickle cell disease (SCD). This has partly been attributed to the loss of splenic function that occurs early in the disease process. We conducted a cross-sectional study and determined the frequency of malaria infection among SCD patients and explored the association with spleen's presence on ultrasonography and spleen function assessed using the frequency of Howell-Jolly bodies (HJBs). A total of 395 participants consisting of 119 acutely-ill SCD patients, 168 steady-state SCD controls, and 108 healthy non-SCD controls were studied. The prevalence of Plasmodium falciparum parasitemia was 51.3% in acutely-ill SCD patients, 31.7% in steady-state SCD controls, and 11.0% in the healthy non-SCD controls; however, the mean parasite density was significantly higher in the non-SCD controls compared to both SCD groups (p = 0.0001). Among the acutely-ill SCD patients, the prevalence of clinical malaria and severe malaria anemia were highest in children <5 years of age. The prevalence of parasitemia (p = 0.540) and parasite density (p = 0.975) showed no association with spleen presence or absence on ultrasonography. Similarly, the frequency of HJB red cells was not associated with the presence of parasitemia (p = 0.183). Our study highlights the frequency and role of malaria infection in acutely-ill SCD patients, especially in those younger than five years. Although we have found no evidence of an increased risk of malaria parasitemia or parasite density with markers of hyposplenism, the role played by an underlying immunity to malaria among SCD patients in malaria-endemic region is not clear and needs further studies.

The main objective of this study is to examine the Determinants of consumer switching behaviour in Nigerian telecommunication industry, the moderating role of value added services. Data were collected from the students of tertiary institutions in Borno state, North eastern Nigeria using a cross-sectional study design. The study adopted Kriejcie and Morgan (1970) rule of thumb and arrived at 382 respondents and questionnaires were distributed and collected through the personally-administered method. Partial Least Squares Structural Equation Modelling (PLS-SEM) was used to test the study hypothesis. This study finds that Value Added Services have significant influence on consumer switching behaviour, while Service Quality and Price have no significant influence on consumer switching behaviour, it also finds that value added services does not moderate the relationship between service quality, price and consumer switching behaviour. The results of this study provide important insights to managers, mobile operators and researchers to further understand the factors that influence consumers to switch from one service provider to another in the Nigerian telecommunication industry. Mobile operators should concentrate on factors like value added services so as to attract more customers to their network.

Due to heavy usage and rising populations, there is a growing need for local and naturally derived materials in the automotive and aerospace industries. Furthermore, due to their excellent mechanical qualities and high strength-to-weight ratio, composite materials are expected to perform better than traditional materials, particularly in automotive and aerospace applications. According to this perspective, this research aims to investigate the effects of optimal compositions of Al–Mg–Si alloy reinforced with palm kernel shell ash (PKSA) particles on dynamic mechanical characteristics of the composite produced via the powder metallurgy route. PKSA compositions of 0, 2, 4, 6, 8, 10 and 12 wt% as reinforcement on Al–Mg–Si powder were used to evaluate the static tensile strength of the produced composites. In this study, the damping factor, change in length, flexural, storage, and loss moduli were determined. In addition, the produced composites’ bulk density, hardness, creep, and dynamic mechanical thermal analysis were also investigated. According to the study’s morphology result, recrystallisation of the powdered composition during ball milling increased dislocation density and harder phases in the PKSA, contributing to the PKSA’s better characteristics. Furthermore, the optimum weight percentage of 6.0 wt% of PKSA (Sample C4) has significant properties compared to the unreinforced (control) sample and was also found to have improved storage modulus, loss modulus, and damping behaviour. These findings showed that the developed composite, particularly sample C4, may be used in various technical applications, including automotive and aerospace industries.

Polycaprolactone (PCL) is a common biopolymer used in tissue engineering for bone-implant due to several properties i.e. Biodegradability. However, PCL is associated with some disadvantages like poor mechanical strength, and low stiffness. In this study, hydroxyapatite (HAp) sourced from sheep bones was synthesized, and for the first time, locally sourced HAp and silica extracted from rice husk ash (RHA) were reinforced with PCL nanoparticles using the solvent casting route to improve the mechanical strength of the biopolymer composite. Then, the effect of the stirring time, RHA and HAp content on the physical and mechanical properties of the scaffold were studied via the Taguchi design of experiment. The porosity of the fabricated scaffolds falls within 19.4 ± 0.62 - 56.6 ± 0.06% as against 70% obtained for the pure PCL. From the mechanical measurement, the compressive strength of the reinforced composite ranges between 8.6 ± 0.01 and 15±0.1 MPa. The compressive strength data obtained in this study shows that the proposed scaffold had improved mechanical strength equivalent to the minimum required mechanical strength of trabecular bone (4–12 MPa). Also, the addition of the RHA and HAp on PCL increase the hardness and fracture toughness significantly. From the grey relational analysis, the optimal performance from the sixteen experiment (L16) runs was obtained with 20 wt.% of RHA content, 30 wt.% of HAp content and stirring time at 30 min. The sample with the optimum parameters is then recommended for further analysis (i.e. in vitro and in vivo)

The study identifies and examines the emerging gap between certificate, knowledge and skills acquisition in the Nigeria educational system especially at the tertiary level. The quality of every emerging nation to greatness is measured on the strength of its human capital development through the acquisition of formal education as Nigeria cannot be an exception. The main problem that triggered this study is to find out the emerging gap of having certificate without corresponding knowledge in Nigeria? The main objective of this study is to examine the effect of certificate without corresponding knowledge and skills in Nasarawa State, Nigeria. The study analyzes the objective of higher education, meaning and importance of examinations, causes and in-depth analysis of examination malpractices in Nigeria tertiary institutions. The study adopts Human Capital Theory as its theoretical framework. The study adopts both primary and secondary method of data collections as its methodology by using simple percentage formula. Using the sample size of 300 out of the entire population of (3030), comprises of staff of Nasarawa State Polytechnic, Lafia (545), College of Agriculture, Science and Technology Lafia (498) Nasarawa State University, Keffi (1015) and Federal Polytechnic, Nasarawa (972). The adoption of criterion means in answering the research questions through the adoption of five point likerts scale format. The finding reveals that the general effects of having certificate without knowledge and skills in Nasarawa State tertiary institutions include promotion of mediocrity, low productivity, lack of quality research, falling academic standard, poor value systems, self-deceit and incompetence in career development. It also showed that the major stakeholders in the education sector shared in the blame of examination malpractices. In view of this, it was however recommended that; the Nigeria education system must wage-war against promotion of mediocrity, low productivity or research, falling academic standard and value systems, self-deceit and incompetence in career development. Secondly the major stakeholders in the Nigeria education sector should not aid and abet examination malpractices. The study concluded that certificate without corresponding knowledge is responsible for the collapse in the educational and societal value system in Nigeria

The study was conducted in and around Gilbedi village and its environs in the Iullemmeden Basin, Sheet 4 SW, Gada local government area, Sokoto, North-West Nigeria. The research area is located in the Sokoto Basin, which is part of the Iullemmeden Basin. The study area is bounded by latitudes 13046'05"N to 13043'22"N and longitudes 5045'00"E to 5040'45"E covering 25 Km2. The mapping exercise was carried out using a topographic base map on a scale of 1:25,000. The observed Dukamaje Formation is derived from a marginal marine depositional setting and is primarily composed of shales, limestones, and mudstone with gypsum intercalation. Shales are consolidated mudstones with a fine-grained texture which is greyish. Limestone is medium to coarse-grained. It is a pale yellow to greyish in color. Petrographic observation showed the grains to be equigranular, and having interstitial quartz cement. The quartz occurs as colorless anhedral crystal with no alteration but with wavy extinction and without cleavage. Other minerals present include muscovite. Based on Folk’s classification for limestone, the limestone in the study area is called “extramicrite” because the allochems are extraclasts. The limestone also lime mud supported which is less than 10% of grains Based on Dunham’s classification schemes for limestone, the limestone of the studied Dukamaje Formation is a “mudstone”.

Aluminium is one of the lightweight materials that have a major contribution in numerous applications globally and it is also considered less expensive compared with other lightweight metals such as titanium and magnesium. As a result of some engineering applications’ requirements of better hardness and strength of material with lesser weight, researchers’ attention is drawn to the enhancement of the mechanical properties of accessible aluminium alloys. This study was conducted to study the microstructure and mechanical properties of a composite Al-Mg-Si matrix with varying weight percentages (0, 4, 6 and 8 wt. %) of palm kernel ash (PKSA) reinforcement, which were denoted correspondingly as C1–C4. The PKSA was obtained at a calcination temperature of 850 °C, XRD and XRF analyses were conducted to characterize it. The formulated samples were then ball-milled using two roll mills for about 60 hours to achieve a near homogeneity of the composites. The SEM image of the reinforced samples (C2 and C3) revealed that there were many networks of coalesced or necked particles while individual particles are hardly found, which is an indication of a high degree of densification ratio percentage of PKSA. The results also showed that there was an increase in hardness (44.4%), modulus of rupture (37.4%) and impact strength (252.03%) of Al-Mg-Si matrix composites (C3) in comparison with the unreinforced matrix material.

The study discusses an overview of small rocket program, development and characterization of locally sourced material at low cost. The aim is to enable the construction of small sounding rocket components for experimental purposes in Nigeria. This paper proposes the utilization of palm kernel shell ash as filler materials in the development, characterization and production of composite material to construct prototype reusable chamber and accessories that will enable it possible for small scientific experiments. To achieve this, particle size and particle range distribution on the microstructure, texture, and mechanical properties of (Al–Mg–Si)/PKSA composites developed by powder metallurgy method were investigated. The access in the 6xxx series of aluminum-magnesium-silicon alloy was investigated for this reason. ImageJ software was used to do particle size analysis professionally and the software was used to calculate the area, mean, standard deviation (SD) and the pixel values. The particle size distribution of big constituent (densification or rather densified solids) particles and small dispersoids possess a finer and slightly elongated grain structure when compared with the unreinforced alloy. The results of the XRD and XRF of all the samples considered showed that Al2O3, SiO2, Mn2O3 and MgO phases were common to all. These hard phases are considered to be responsible for improved mechanical properties and resistance of the composite, while the SEM result showed that the reinforcement was uniformly distributed which further improves the mechanical property of the composite.Keywords: Microstructure, Composite, Rocket, Palm Kernel

Nowadays, the demand for naturally and locally sourced materials for usage in automobile and aerospace have been on the increase due to high usage and population increase. In this view, this research is focused on investigating aluminium metal matrix composite materials with the aim of studying the optimum composition effect of Al-Mg-Si alloy reinforced with Palm Kernel Shell Ash (PKSA) particle on static and dynamic properties. Powder methodology was used to manufacture the developed composites. The SEM result showed that the recrystallization during ball milling of the mixture powders characterized the accumulation of higher dislocation density and the presence of harder phases in the PKSA which contributed to their improved thermal properties. Furthermore, the modulus of rupture of the developed Al-Mg-Si-PKSA matrix composites was effectively increased, and it can be drawn that sample C4 (6:94 wt%) has optimized properties. In this study, the storage modulus ( E ’), loss modulus ( E '), damping factor (tan δ ) were determined based on the Dynamic Mechanical Thermal Analysis (DMTA) of the developed composites. It was established that the glass transition temperature ( Tg ) increased with frequency and amplitude. The result of this research also revealed the optimum percentage composition of 6 wt% PKSA on Al-Mg-Si powder is suitable for research aerospace applications.

Blast furnace slag functionalized with sulfamic acid (zwitterion) shows an extraordinary potential for the removal of biogenic amines from spiked water and real wastewater samples. The functionalized slag is characterized using scanning electron microscopy-energy dispersive spectroscopy (SEM/EDS), Fourier transform infrared spectroscopy (FTIR), and acid site density test. Its performance toward the removal of selected biogenic amines (putrescine, tyramine, and 2-phenylethylamine) is evaluated at different experimental conditions that include pH, contact time, adsorbent dosage, and initial concentration. The central composite experimental design is employed in investigating the effect of these individual factors and their interactions. The adsorption experiment results fit both the Langmuir isotherm model and pseudo-second-order kinetic model based on the computed high coefficient of determination (R-2) values. Maximum adsorption capacity values of 80.64 mg g(-1) for 2-phenylethylamine, 12.5 mg g(-1) for putrescine, and 64.52 mg g(-1) for tyramine are estimated from the Langmuir isotherm model. Hydrogen bonding interaction between the S = O groups of the functionalized slag and protonated amino groups of biogenic amines is speculated as the possible mechanism of adsorption. The prepared functionalized slag also exhibits good adsorptive removal of biogenic amines in a date palm fruit processing industrial wastewater sample.

The debate on the effective of the credit channel of monetary policy transmission has been a burning issue on monetary policy discourse for a while. Romer and Romer (1989), Ramsey (1993), Oliner and Rudebusch (1995), and Morris and Sellon (1995) raised some doubts about the existence and effectiveness of the credit channel. Alternatively, several other studies have found support for the credit/bank lending channel (see for instance, Bernanke and Blinder (1988), Bernanke and Blinder (1992), Gertler and Gilchrist (1994), Bernanke and Gertler (1995), Peek and Rosengren (1995), Kashyap, Stein and Wilcox (1993), Kashyap and Stein (1995, 2000), and Suzuki (2004). Therefore, the validity of bank lending/credit channels remains largely inconclusive and an empirical issue. Although the transmission mechanism of monetary policy in Nigeria has been examined in numerous studies, there is no consensus on the most effective channel; and there is scant evidence of the role of credit channel in the transmission of monetary policy. In this paper, we examine the validity and efficacy of the credit channel in the monetary policy transmission in Nigeria, using a vector autoregressive model to analyse monthly data spanning ten years (2008-2018). The empirical analysis relies on Uslu (2016) modified slightly to substitute Bank total asset and Bank deposits to represent the asset side and liability side of the bank's balance sheet, respectively. Purchasing Managers Index (PMI), consumer price index (CPI) and the real effective exchange rate (REER) are used as proxy for development in macroeconomic activity; while all share index (ASI) and market capitalization (MK) denote substitutable assets in the balance sheet of the banks. All series except the money market rates were transformed into natural logarithms. In addition, nominal series were transformed to real variables by normalization using the consumer price index. We find that a positive shock to monetary policy rate has no effect on bank lending to private sector. This could be due to a few factors. Primarily, the Nigerian financial industry is plagued by a low ratio of lending to private sector. Nigerian banks show a preference for government bonds and other securities, which stifles lending to the presumably risky private sector. It is also possible that monetary policy rates are already so high, driven by Nigeria's growing debt needs and exchange rate crises; that the lending to private sector has declined to such a level that it no longer responds to positive credit shocks.

In this study, hydroxyapatite (HAp) was extracted from catfish bones (CB) and non-separated animal bones (NB). The bioceramic samples were prepared by a facile synthesis route and the representative scaffolds were prepared by cold compaction and sintered at 900 degrees C, 1000 degrees C and 1100 degrees C. To evaluate the properties of the produced HAp, X-ray diffraction (XRD) and Fourier Transform Spectroscopy (FT-IR) analyses were carried out. The evaluation of the hardness of the representative bio-derived scaffolds was experimentally conducted while the fracture toughness and brittleness index were obtained by calculation using the hardness test parameters. The experimental data showed that as temperature increased up to 1000 degrees C for CB, there was a consequential increase in hardness, while for NB, hardness values reduced throughout the sintering regimes. These gradients in mechanical measurements are ascribed to phase changes during heat treatment. (C) 2020 The Authors. Published by Elsevier Ltd.

In this study, the electrochemical dechlorination of different polychloromethanes (CCl4, CHCl3, and CH2Cl2) on a Co-MoS2 graphite felt cathode was investigated. The Co-MoS2 electrocatalyst was prepared hydrothermally on a graphite felt support. The prepared catalyst’s characterization revealed the formation of hybridized CoSx and MoS2 nanosheets deposited on the pore structures of graphite. The influencing factor for the electro-dechlorination parameters such as applied current density, pH, and sample concentration on the dechlorination rate was optimized. A significant capacitive reduction current density peak of approximately 1 mA/cm2 was noted for CCl4 at a potential of −0.3 V (vs. AgCl). The dechlorination mechanism was attributed to the stepwise hydrogenolysis mechanism that involves the organochlorides bond cleavage by H* insertion. It was noted that the Co-MoS2 graphite felt electrode exhibited excellent catalytic activity toward the reduction of each of the chlorinated compounds with high selectivity toward the higher-order organochloride. Moreover, the dechlorination rates for each of the compounds were suited to the first-order kinetic model, and the estimated apparent rate constants showed the dechlorination in the following sequence CH2Cl2 (k3 = 9.1 × 10−5 s−1) < CHCl3 (k2 = 1.5 × 10−3 s−1) < CCl4 (k1 = 2.8 × 10−3 s−1).

Surface functionalization of blast furnace slag with sulfamic acid (a zwitterion) was performed for the removal of Cr3+ and methylene blue dye (MB) from water samples. The slag functionalization process was optimized using Response Surface Methodology Design. Statistical analysis of the parameters that include the sulfamic acid amount (A), reaction time (B), and temperature (C) revealed that (A) increase had a negative effect on the adsorption of both pollutants by the zwitterion slag, whereas (B) and (C) increase presented a positive impact. At the optimum condition of 2 g sulfamic acid amount, 50 min reaction time and 37 degrees C temperature, the prepared slag showed a removal efficiency of more than 90% for both Cr3+ and MB. Surface characterization by SEM/EDS, FTIR, XPS and surface area analyser, showed an improvement in surface properties and the incorporation of zwitterionic NH2+ and S=O groups of sulfamic acid. Adsorption isotherm and kinetic studies conducted with the zwitterion slag showed the adsorption process was suited to Freundlich isotherm model and pseudo-second-order kinetic model. The thermodynamic study conducted revealed the spontaneity of the process based on the calculated negative Delta G (Gibb's free energy) values. The prepared zwitterion slag offered easy regeneration with dilute HCl solution and showed a considerable removal (Cr3+: 65% and MB: 80%) for both pollutants even after 3 cycles of usage. (C) 2020 The Chemical Industry and Engineering Society of China, and Chemical Industry Press Co., Ltd. All rights reserved.

The present work describes the synthesis, optimization, and evaluation of synthesized hydroxyapatite (HAp) from catfish bones (CB). This is with a view to achieving optimum processing conditions and sustainable pedagogical approaches for the preparation of hydroxyapatite scaffolds for tissue engineering. The catfish bones derived hydroxyapatite were prepared through conventional sintering, and low-cold compaction pressure (1 MPa), while the Box-Behnken statistical design tool was used in determining the optimum preparation conditions. Analytical studies were performed on the synthesized HAp to elucidate the physico-chemical and mechanical characteristics of the designed formulation. Three parameters; heating temperatures, holding times, and, sieve sizes were adopted to establish a significant correlation on the physico-mechanical characteristics of the fabricated HAp scaffolds. From the design of experiment (DOE), heating temperature proved to have the most significant effect on the material's mechanical and physical properties when compared to holding times and sieve sizes, with compressive strength (13 MPa), density 1.856 g/cm3 and fracture toughness (2.407 MPa m1/2) observed to be the most improved properties in that order. The physico-mechanical properties of the hydroxyapatite scaffolds reached an optimum at 900 degrees C, 2 h 22 min holding time, and at a particle size of 100 mu m. X-ray diffraction and Fourier transform infra-red studies showed that at every experimental run, optimum run (R6) inclusive, hydroxyapatite with remarkable purity was formed. This study, therefore, illustrates the optimum process for the synthesis of catfish bones derived hydroxyapatite revealing the most significant interactions responsible for achieving clinically useful hydroxyapatite scaffolds with a computational pedagogical approach Table 1 that is useful for innovations in Preset bioengineerng conditions for education. optimization study.

The solution combustion route was used to fabricate strontium (Sr) doped hydroxyapatite (HAp). A low compaction pressure method was adopted for pelletizing the powders (Sr-HAp) prior to physical and mechanical properties measurement. Physiological stability of the pellets was conducted by immersing in Phosphate Buffer Saline (PBS) solution for 24 h. The Sr-HAp produced a comparatively higher hardness and fracture toughness of 0.38 GPa and 0.82 MPa.m(1/2) compared with 0.20 GPa and 0.67 MPa.m(1/2) for undoped HAp. The SEM images suggested that strontium co-existed with the calcium ion in hydroxyapatite due to the presence of irregular bead-like structures on a micro-scale. The Sr-HAp pellets were stable in Phosphate Buffer Saline solution.