200 research outputs found
On Sensor-Based Ore Sorting
The high cost of mineral processing in mining industries keeps rising. Sensor-based ore sorting is key in helping the mining industries to sort out ore to help reduce the processing and production costs. With the implementation of sensor-based ore sorting at the primary stage, it assures of separating larger volumes of the barren gangue from the conveyor-transported ore before excessive handling and mixing occurs. Hence, this paper investigated and evaluated the deployment of the colour camera and the dual energy X-Ray sensors. The successful operation at 2.8 m/s and 3.2 m/s of conveyor speed, and relatively extreme positions of the air jet-based separation mechanism for the sorting proved robustness in separation of barren gangue from the ore feed
Improving Land Tenure Security through Customary Boundary Demarcation- A Case Study
In sub-Saharan Africa, one of the barriers to development and wealth creation in the peri urban and rural areas is land tenure insecurity. This is mainly due to a number of factors including the absence of clear unambiguous boundaries between allodial owners and the absence of credible documentation of land rights. This research sought to establish and document over 190 km of the boundary of Juaben paramouncy in a manner that ensured peace, harmony and tenure security. Disputes were resolved through less costly Alternative Dispute Resolution (ADR) mechanisms and Customary Land Secretariat (CLS) that catalogued and maintained up to date register on the land. This resulted in conflicts that have raged on for decades, sometimes leading to injury, property destruction and loss of lives come to an end. The benefits of this improved land tenure security are enhanced agricultural productivity, wealth creation for rural dwellers, peace and stability. Boundary demarcations and documentations established were important steps in the process of reformation and improving land tenure security in the rural communities. Information retrieval was simplified and transaction cost made cheaper. Keywords: Land Tenure Security, Customary Boundary Demarcation (CBD), Alternative Dispute Resolution (ADR
Effects of natural and synthetic soil conditioners on soil moisture retention and maize yield
The efficacy of a natural soil conditioner, Coco-Peat (C-P), and synthetic soil conditioners, Terawet (T-200) and Teraflow (T-F), in improving soil moisture content were examined on five Ghanaian soil series (Akroso, Akuse, Amo, Hake and Oyarifa). In general, the water retention of T-200 and C-P treated soils were similar but significantly higher (p < 0.001) than that of T-F and the control (C-T) treated soils, which were also similar on all the test soils. The dry matter yields of the test crop (maize) were 5.4, 5.2, 4.5 t ha-1 on T-200, C-P and T-F treated soils, respectively, on Akroso series. These yields were 36%, 31% and 5%, respectively, more than those of the control treatment. On Akuse series even though T-200 and T-F gave higher dry matter yields than the control, the differences were not significant, only C-P treatment gave significantly higher (p < 0.001) yield than the control. On Amo series, dry matter yields of 6.1, 5.8 and 4.9 t ha-1 on T-200, C-P and T-F treated soils, respectively, were 38%, 31% and 10% more than the control treatment. On Hake series, T-200, C-P and T-F treatments improved dry matter yields by 45%, 32% and 12%, respectively, over that of the control. The greatest effect of the polymeric absorbents was observed on the sandy/clay/loam Oyarifa series. The treatments T-200, C-P and T-F improved dry matter yields by 92%, 81% and 4%, respectively, over the control treatment. The results indicate that the differences in yields over the control were due to the improved water retention ability of the soils amended with the polymeric absorbent
The dose adherence computation model: a critical review of anti-retroviral drug level of adherence computation
Lipid and Lipoprotein Levels in Type 2 Diabetes Patients Attending the Central Regional Hospital in the Cape Coast Metropolis of Ghana
Purpose: To ascertain the prevalence of dyslipidaemia in diabetics in Cape Coast.Methods: This preliminary outpatient-based cross-sectional study was conducted in 79 diabetic patients (22 males and 57 females) receiving treatment at the Central Regional Hospital (CRH) in the Cape Coast Metropolis. Serum lipid profiles of the fasting diabetic patients were determined between September, 2008 and May, 2009. In addition, demographic information, height and weight were measured and BMI was computed.Results: BMI was significantly (P = 0.001) higher in females than in males, but the mean values of all the remaining measured parameters were comparable (P>0.05) between the sexes. No significant (P>0.05) correlation was observed between age or BMI and cholesterol levels. Percentage dyslipidaemia ranged from 7.60% to 55.70% in the studysample. A significantly (P<0.05) higher proportion of females than males in the entire sample were overweight/obese, had higher levels of total cholesterol (TCHOL) and TRG. No significant difference (P>0.05) was observed between proportions of individuals in both sexes who exhibited higher LDL-c but lower levels of HDL-c..Conclusion: Lipid profile should be a routine test for all diabetics receiving treatment at the CRH to identify those at increased cardiovascular risk for immediate attention.Keywords: Dyslipidaemia, Cardiovascular, Cholesterol, Body mass inde
Structure and decay of a proto-Y region in Tilapia, Oreochromis niloticus
Funding for Open Access provided by the UMD Libraries Open Access Publishing Fund.Sex-determination genes drive the evolution of adjacent chromosomal regions. Sexually antagonistic selection favors the accumulation of inversions that reduce recombination in regions adjacent to the sex-determination gene. Once established, the clonal inheritance of sex-linked inversions leads to the accumulation of deleterious alleles, repetitive elements and a gradual decay of sex-linked genes. This in turn creates selective pressures for the evolution of mechanisms that compensate for the unequal dosage of gene expression. Here we use whole genome sequencing to characterize the structure of a young sex chromosome and quantify sex-specific gene expression in the developing gonad. We found an 8.8 Mb block of strong differentiation between males and females that corresponds to the location of a previously mapped sex-determiner on linkage group 1 of Oreochromis niloticus. Putatively disruptive mutations are found in many of the genes within this region. We also found a significant female-bias in the expression of genes within the block of differentiation compared to those outside the block of differentiation. Eight candidate sex-determination genes were identified within this region. This study demonstrates a block of differentiation on linkage group 1, suggestive of an 8.8 Mb inversion encompassing the sex-determining locus. The enrichment of female-biased gene expression inside the proposed inversion suggests incomplete dosage compensation. This study helps establish a model for studying the early-to-intermediate stages of sex chromosome evolution.https://doi.org/10.1186/1471-2164-15-97
Nano-Doped Monolithic Materials for Molecular Separation
Monoliths are continuous adsorbents that can easily be synthesised to possess tuneable meso-/macropores, convective fluid transport, and a plethora of chemistries for ligand immobilisation. They are grouped into three main classes: organic, inorganic, and hybrid, based on their chemical composition. These classes may also be differentiated by their unique morphological and physicochemical properties which are significantly relevant to their specific separation applications. The potential applications of monoliths for molecular separation have created the need to enhance their characteristic properties including mechanical strength, electrical conductivity, and chemical and thermal stability. An effective approach towards monolith enhancement has been the doping and/or hybridization with miniaturized molecular species of desirable functionalities and characteristics. Nanoparticles are usually preferred as dopants due to their high solid phase dispersion features which are associated with improved intermolecular adsorptive interactions. Examples of such nanomaterials include, but are not limited to, carbon-based, silica-based, gold-based, and alumina nanoparticles. The incorporation of these nanoparticles into monoliths via in situ polymerisation and/or post-modification enhances surface adsorption for activation and ligand immobilisation. Herein, insights into the performance enhancement of monoliths as chromatographic supports by nanoparticles doping are presented. In addition, the potential and characteristics of less common nanoparticle materials such as hydroxyapatite, ceria, hafnia, and germania are discussed. The advantages and challenges of nanoparticle doping of monoliths are also discussed
Transactions Processing Subsystems for Databases Based On ARIES Write-Ahead Logging for The Client-Server Architecture Approach
This paper proposes a formal framework specification that applies an advanced recovery mechanism, functional in a client-server architecture while addressing atomicity and consistency issues. Another palpable issue in using such dominant architectures is recovery. This paper also addresses this issue in context with the client-server architecture using extensions of the original ARIES algorithm and concepts of Software Transaction Memory. This novelty has been successfully implemented and tested for propriety and applicability
A Flexible Framework For Implementing Multi-Nested Software Transaction Memory
Programming with locks is very difficult in multi-threaded programmes. Concurrency control of access to shared data limits scalable locking strategies otherwise provided for in software transaction memory. This work addresses the subject of creating dependable software in the face of eminent failures. In the past, programmers who used lock-based synchronization to implement concurrent access to shared data had to grapple with problems with conventional locking techniques such as deadlocks, convoying, and priority inversion. This paper proposes another advanced feature for Dynamic Software Transactional Memory intended to extend the concepts of transaction processing to provide a nesting mechanism and efficient lock-free synchronization, recoverability and restorability. In addition, the code for implementation has also been researched, coded, tested, and implemented to achieve the desired objectives
Polyurea-Functionalized Multiwalled Carbon Nanotubes
An in situ polycondensation approach was applied to functionalize multiwalled carbon nanotubes (MWNTs), resulting in various linear or hyperbranched polycondensed polymers [e.g., polyureas, polyurethanes, and poly(urea-urethane)-bonded carbon nanotubes]. The quantity of the grafted polymer can be easily controlled by the feed ratio of monomers. As a typical example, the polyurea-functionalized MWNTs were measured and characterized in detail. The oxidized MWNTs (MWNT-COOH) were converted into acyl chloride-functionalized MWNTs (MWNT-COCl) by reaction with neat thionyl chloride (SOCl2). MWNT-COCl was reacted with excess 1,6-diaminohexane, affording amino-functionalized MWNTs (MWNT-NH2). In the presence of MWNT-NH2, the polyurea was covalently coated onto the surfaces of the nanotube by in situ polycondensation of diisocyanate [e.g., 4,4‘-methylenebis(phenylisocyanate)] and 1,6-diaminohexane, followed by the removal of free polymer via repeated filtering and solvent washing. The coated polyurea content can be controlled to some extent by adjusting the feed ratio of the isocyanato and amino groups. The structure and morphology of the resulting nanocomposites were characterized by FTIR, NMR, Raman, confocal Raman, TEM, EDS, and SEM measurements. The polyurea-coated MWNTs showed interesting self-assembled flat- or flowerlike morphologies in the solid state. The signals corresponding to that of the D and G bands of the carbon nanotubes were strongly attenuated after polyurea was chemically tethered to the MWNT surfaces. Comparative experiments showed that the grafted polymer species and structures have a strong effect on the Raman signals of polymer-functionalized MWNTs
- …