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Mining for specialized metabolism genes in Red Sea brine pool prokaryotic metagenomes for antibacterial and anticancer activities by Ziko, Laila
Published 2019“…A subset of specialized metabolites (SMs) produced by microbes confer activities of pharmaceutical importance, such as antibacterial and anticancer effects, and are coded by specialized metabolism gene clusters (SMGCs) in the organisms’ genomes. …”
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Page will reload when a filter is selected or excluded.- ASME 3 results 3
- FE Modeling 3 results 3
- "This research work investigated the modeling of Von Mises stress in LNG Spherical Carbon Steel Storage tank using assumed displacement Finite Element analysis based on shallow shell triangular elements. Using equations of elasticity, constant thickness carbon steel spherical storage tanks were subjected to different loading conditions. This paper stresses the need for proper definition of shallow element using sector angles to obtain the shallowness. The shallow spherical triangular element has five degrees of freedom at each of its corner node, which are the essential external degrees of freedom. The assumed displacement fields of these shallow triangular elements satisfied the exact requirement of rigid body modes of motion. The FORTRAN 90 programming language was used for the programme coding to solve finite element equations resulting from the model while Von Mises stresses distribution within the spherical storage tank shell subjected to different internal pressures were determined. The results showed that the use of non-shallow elements due to improper sector angles resulted in unreliable results while real shallow elements produced results that tallied with ASME Section VIII Div 1, Part UG values. " 2 results 2
- ASCE 2 results 2
- FEM 2 results 2
- LNG 2 results 2
- Spherical Storage Tank 2 results 2
- Von Mises Stress 2 results 2
- "This work investigated the distribution of Von Misses stress in LNG Spherical Carbon Steel Storage tanks. Using the Finite Element Method and equations of elasticity, constant thickness carbon steel spherical storage tanks of 40 in. dia. 70in. dia of 1 in. shell thickness were subjected to different loading conditions from 500 to 4000Psi in incremental of 500 Psi. Spherical triangular elements based on shallow shell formulation were used for the model. The element has five degrees of freedom at each corner node, which are the essential external degrees of freedom without the degree of freedom associated with the in-plane shell rotation. The displacement fields of the element satisfy the exact requirement of rigid body modes of motion. The FORTRAN 90 coding was developed to obtain maximum Von Misses stress distribution with the tank subjected to different internal pressure and wind loadings. The results were then compared with the yield stress of the material of the tank. Von Misses stress is used as yield criteria whether to change tank material or increase the shell material thickness if yield stress is higher than the Von-Misses Stress. Results showed Von Mises stresses for a 40 in dia. Spherical shell with 1 in shell thickness able to withstand internal pressure loading alone up to 3500 Psi after which the shell thickness will no longer be able to withstand the loading. The 70in. dia. Vessel could only withstand internal pressure loading up to 2000 Psi. Validation of Finite Element modeling was done using ASME Section VIII Div 1 standard. Modeled results were observed not to be significantly different from ASME values (P>0.05). External wind effects alone on small dia. vessels was seen to be constant for all sides of the pressure vessel. 1 results 1
- A series of experiments were conducted to measure the influence of the duration of exposure to inclement weather after cracking on the bulk density, solid or true density, porosity, and water absorption characteristics of palm kernel shells (PKS). The results showed that the bulk and true densities decreased respectively from 0.60g/cm3 and 1.37g/cm3 for freshly cracked shells to 0.53g/cm3 and 1.25g/cm3 for shells that have been exposed to inclement weather for over ten years after cracking. The porosity and ability to hold moisture increased with the duration of exposure. These experimental observations are attributable to the organic nature of the shells as a result of which there is a gradual biodeterioration especially of the adhering fibers. This reduces the dry matter content and increase the void. Density values obtained are comparable with other materials of construction such as earth and wood which is an indication that PKS has potentials for use as a material for construction. Further work on the mechanical properties of the material is recommended. 1 results 1
- A survey involving the use of structured questionnaires and personal communication was carried out in Western Nigeria to ascertain the type and extent of use of silos for the storage of grains. Steel and Aluminium were found to be the predominant materials used for the construction of the silos. They are mainly used to store shelled corn and in a few instances, rice, cowpea and soybean. The prohibitive cost of silo acquisition limits their ownership and use to the Ministries of Agriculture, Co-operative Societies, agro-based industries, Teaching and Research Institutes and a few large scale private farms. Silos are not used by the small to medium scale farms. The withdrawal of the Ministries of Agriculture from direct grain production and the collapse of co-operative grain storage programmes have resulted in the abandonment of many silos. The metal silos experience the problem of moisture condensation on the roofs and walls which leads to the deterioration of stored grains through moulding, caking and rapid multiplication of insects. Losses of as much as 10% of total storage through these sources have been recorded for some silos. Adequate funding of current research efforts to develop local materials for grain silo construction is recommended. 1 results 1
- ANOVA 1 results 1
- Area Coordinates 1 results 1
- Ash 1 results 1
- BS 1 results 1
- Cashew nut shell 1 results 1
- Condensation, 1 results 1
- Conjugated polymers 1 results 1
- Conjugated polymers which interact with biological systems have attracted interest due to their high conductivity, stability and electronic properties. Substituted polymers of 3-methyl pyrrole-4-carboxylic acid (MPCa) have been synthesised and used as components of biosensor, while unsubstituted polypyrroles are not effective for such application. However the mechanism of interaction, nature, the relative importance of dynamic and static electron correlation of the polymers are not completely understood. This research was designed using computational approach to study the molecular properties of substituted and unsubstittued pyrrole polymers with a view to understanding what make polymers of substituted pyrroles suitable components of biosensor. Structures of unsubstituted Pyrrole (Py); substituted pyrroles which include 3-methyl- pyrrole-4-carboxylic acid (MPCa), 3-methyl-pyrrole-4-carboxamide (MPCam), 3- methyl-pyrrole-4-sulfonic acid (MPSO3H), 3-methyl-pyrrole-1-carboxylic acid, (MPCb), 3-methyl-pyrrole-4-carbothioic acid (MPCOSH), 3-methyl-pyrrole-4- carbaldehyde (MPCHO) and their polymers were studied using quantum mechanical approach. The molecular properties investigated were Energy gap (Eg), Koopman’s reactivity descriptors, Fukui function, Lowest Unoccupied Molecular Orbital (LUMO), Highest Occupied Molecular Orbital (HOMO) and thermodynamic properties. These were calculated using restricted hybrid density functional theory with Becke three, Lee Yang and Parr at 6-31G(d) basis set. The calculated Eg were extrapolated to polymer through second order-degree polynomial equation. Spin-flip time density functional theory and coupled cluster single and double method with 6-311++G(d,p) basis set were used to calculate Coupled Cluster operator (T1) diagnostic and Vertical Singlet- Triplet (VST) gap to accurately determine polymers suitability as components of biosensor. All calculations were carried out using quantum mechanical software. The calculated Eg of the polymers decreased with increasing chain length and the nature of substituent. The order of Eg was MPCHO > Py > MPCb > MPCa > MPCam > MPSO3H > MPCOSH, with MPCOSH having the lowest value of 1.7 eV. Substituted polypyrroles except MPCHO have stronger electron-electron interactions since electron-electron interaction is more when the Eg is low (between 1.0 and 3.0 eV). Koopman’s reactivity descriptors were within the range of -3.9 to 2.4 eV (chemical i potential), 1.5 to 2.1 eV (chemical hardness) and 1.4 to 4.4 eV (electrophilicity index). Fukui function revealed a high electron density around the substituted functional groups and the LUMO and HOMO were extended over the C-C and C=C bonds. Thermodynamic parameters were enthalpy change (-4361.1 to -1045.7 kJmol-), entropy change (540.3 to 952.2 Jmol-1K-1) and free energy change (∆G0f) (-4361.2 to - 1045.8 kJmol-1) indicating spontaneous formation of the polymers. The T1 diagnostic of unsubstituted polypyrroles ranged from 0.0015 to 0.0013, while substituted polypyrroles ranged from 0.030 to 0.065. The T1 <0.02 indicated that unsubstituted polypyrrole had dynamic correlation with single reference (closed shell), while T1 >0.02 showed that substituted polypyrroles possessed static electron correlation with multireference (open shell) nature. The VST gap of unsubstituted polypyrroles ranged from 3.0 to 4.8 eV, while substituted polypyrroles ranged from 3.1 to 5.3 eV. The VST gap >0 revealed that all studied systems have a singlet ground state. The presence of substituents on polypyrrole decreased the energy gaps which led to the enhancement of their molecular properties making them suitable components of biosensor. 1 results 1
- Convex cut battles 1 results 1
- Cryogenic 1 results 1
- Drilling Fluid 1 results 1
- EIA 1 results 1
- Eflciency 1 results 1
- Energy gap 1 results 1
- Evaluation 1 results 1
- Experiments were carried out to determine the dimensions of palm kernel, the shell thickness, kernel and nut densities as useful parameters in its handling and processing. The major, intermediate and minor diameters of the kernel were found to vary from 26.5 to 44, 21.5 to 34.5 and 16.5 to 28mm respectively. Sphericity was calculated to be between 76 and 80 and was independent of the size of the kernel. Nut densities varied from 0.8 to 2g/cm3 while kernel densities varied from 0.93 to 1.33g/cm3. The nut densities were generally higher than the kernel densities and the variation is attributed to the large volume but lightweight of the shell. The shell thickness varied from 2 to 6.5mm. These parameters are useful in the design of handling and processing equipment for palm kernel 1 results 1
- FORTRAN 90 1 results 1
- Field Fabricated Pressure Vessels 1 results 1
- Fluctuation, 1 results 1
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