Search

G-quadruplex (G4) DNAzymes with peroxidase activities hold potential for applications in biosensing. While these nanozymes are easy to assemble, they are not as efficient as natural peroxidase enzymes. Several approaches are being used to better understand the structural basis of their reaction mechanisms, with a view to designing constructs with improved catalytic activities. Spermine alters the structures and enhances the activities of some G4 DNAzymes. The reported effect of spermine in shifting the conformation of some G4 DNAzymes from antiparallel to parallel has not been tested on multimeric G4 DNAzymes. In this study, we examined the effects of spermine on the catalytic activities of multivalent constructs of Bcl2, c-MYC, PS2.M, and PS5.M. Our findings show that spermine significantly improved the peroxidase activity of PS2.M, an antiparallel G4 DNAzyme, while there was no significant effect on c-MYC, which already exists in a parallel conformation. The addition of spermine led to a substantial increase in the initial velocity of PS2.M and its multimeric form, enhancing it by approximately twofold. Therefore, spermine enhancement offers promise in expanding the range of DNAzymes available for use as biosensing tools. [ABSTRACT FROM AUTHOR]

The energy absorption characteristics of composites are developed for applications likely to be subjected to sudden or prolonged impacts. In lightweight applications, the possibilities of Al 6061 composites are being explored with various known materials with similar properties. Three materials of low densities but high strength was combined: hexagonal honeycomb Al 6061 core was sandwiched with polyurethane foam and embedded within two glass fiber-reinforced polymer plates. L-9 orthogonal array Taguchi DOE was adopted for the design of the experiment varying the polyurethane mixture, core height, and face sheet thickness using the three-factor method. From the output of the Taguchi DOE, twenty-seven samples were fabricated. In order to determine the force-displacement relationship for each of the test samples, a three-point bending test was performed on a universal testing machine. Energy absorption (EA) and crushing force (CF) were determined from the force and displacement values. These values were then optimized to minimize the PCF while maximizing EA. Numerical analysis performed correlated with the results from experimental samples after testing. Since energy absorption is a measure of applied force and the resulting displacement on a material, the energy absorption characteristics were discussed. [ABSTRACT FROM AUTHOR]

A coupled Mori-Tanaka/finite element strategy was implemented to capture deformation profiles of aluminum AA 6063 cylindrical and hexagonal tubes reinforced with 60% variable coir-fiber thickness (5 mm, 10 mm) coir-fiber under variable oblique crushing. By a representative volume element (RVE) defined elastic moduli of the reinforcement phase hybrid tubes were simulated for the effect of reinforcement layer thickness under the Johnson-Cook's and Hashin's intralaminar damage with cohesive zone modeling. As, transformations in deformation underscored variabilities in shape, multicellularity and reinforcement thickness, a correlation is found between loading angles and peak crushing forces in evolving a lightweight absorber consistent with extreme oblique impacts. [ABSTRACT FROM AUTHOR]

SS 316L, a low-carbon 316 Stainless Steel, has been used to manufacture swivel mechanisms for paraplegic patients, but its weight is relatively high compared to a few materials in its range of properties. Aluminum alloy 6061 and Titanium alloy (Ti6Al4V) offer lightweight and incredible strength-to-weight ratio, hence their use for medical, aerospace, and automotive applications. This study, therefore, seeks a replacement for SS 316L. A 3D model of a swivel mechanism was developed to compare the performance of the swivel mechanism made with SS 316L, AA 6061, and Ti6Al4V. The kinematic analysis of the mechanism based on a range of weights: 1kN, 1.1 kN, 1.2 kN, 1.3 kN, 1.4 kN, and 1.5 kN was carried out to generate the inputs for the simulation. The 3D model was made with SolidWorks, and the results of the kinematic analysis were used to define the simulation parameters for the mechanism. Two scenarios generated depicted the full collapse of the mechanism and the full extension. The results showed that AA 6061 and Ti6Al4V outperformed SS 316L with higher yield strength and factor of safety. Therefore, swivel plates made with AA 6061 and Ti6Al4V have higher yield strength than those made with SS 316L, adding to the advantage that they have a higher strength-to-weight ratio. From this analysis and known knowledge of the cost of these materials, the optimal replacement considering cost with yield strength is AA 6061. However, Ti6Al4V is a better alternative for the strength-to-weight ratio for SS 316L. [ABSTRACT FROM AUTHOR]

This article is a book review of "Contemporary issues in Christian marriage: In commemoration of the retirement of Rev. Dr. Samuel Oluwafemi Oladimeji from active ministry of the Nigerian Baptist Convention." The book is a collection of essays on various topics related to marriage, written by different contributors. Each chapter addresses a different aspect of marriage, such as discerning God's will in selecting a partner, making the best of the dating period, and communication in the Christian home. The book also includes a short biography of Rev. Dr. Samuel Oluwafemi Oladimeji. While the book covers many important topics, the reviewer notes that some contemporary issues, such as divorce and artificial intelligence's role in marriage, are not addressed in the book. [Extracted from the article]

Sweet potatoes are extremely adaptable to adverse environmental conditions and can increase food security in times of drought and famine. However, in recent times sweet potato production has been on the decline due to pest and disease infestation. The objectives of the study were to describe the socio-economic characteristics of the sweet potato farmers; identify the common field/storage pest and disease of sweet potato; investigate the indigenous measures of controlling field/storage pests and diseases among others. One hundred and twenty-two sweet potato farmers were randomly selected from two local government areas. The study shows that majority of the sweet potato farmers were male (89.3%) and married (80.4%). The major field and storage pests were armyworm (100%), grasshopper (100%), and rat (100%). Black rot (x=2.39), and bacterial wilt (x=2.35) were the major field and storage diseases of sweet potato. The major challenges faced by sweet potato farmers with use of indigenous methods were proximity to natural herbs (100%). The study concluded that the use of indigenous measures to control sweet potato pest and diseases are very effective and beneficial. Therefore, the study recommended that Extension agent should work with the farmers on how the natural herbs can be preserved within their environment. [ABSTRACT FROM AUTHOR]