New Generation of Hybrid Materials Based on Gelatin and Bioactive Glass Particles for Bone Tissue Engineering

Hybrid scaffolds based on bioactive glass (BAG) particles (<38µm), covalently linked to the gelatin (G*), using 3-glycidoxypropyltrimethoxysilane (GPTMS), have been studied for bone bioengineering. In this study, two glass compositions (13-93 and 13-93B20 [where 20% of the SiO2 was replaced with B2O3]) were introduced in the gelatin matrix. The Cfactor (Gelatin/GPTMS molar ratio) was kept constant at 500. The hybrids obtained were found to be stable at 37°C, in solution; condition at which pure gelatin is liquid. All hybrids were characterized by in vitro dissolution in TRIS solution (for up to 4 weeks) and Simulated Body Fluid (SBF) (for up to 2 weeks). Samples processed with 13-93B20 exhibit a faster initial dissolution and significantly faster precipitation of a hydroxyapatite (HA) layer. The faster ion release and HA precipitation recorded from the G*/13-93B20 samples, is attributable to the higher reactivity of borosilicate compared to the silicate glass. MC3T3-E1 cells behavior, in direct contact with the hybrids, was investigated, showing that the cells were able to proliferate and spread on the developed biomaterials. Tailoring the glass composition allows to better control the material’s dissolution, biodegradability, and bioactivity. Bioactive (especially with 13-93B20 BAG), and biocompatible, the hybrids are promising for bone application.

Characterization of amyloid β fibril formation under microgravity conditions

Amyloid fibrils are self-assembled and ordered proteinaceous supramolecules structurally characterized by the cross-β spine. Amyloid formation is known to be related to various diseases typified by neurogenerative disorders and involved in a variety of functional roles. Whereas common mechanisms for amyloid formation have been postulated across diverse systems, the mesoscopic morphology of the fibrils is significantly affected by the type of solution condition in which it grows. Amyloid formation is also thought to share a phenomenological similarity with protein crystallization. While many studies have demonstrated the effect of gravity on protein crystallization, its effect on amyloid formation has not been reported. In this study, we conducted an experiment at the International Space Station (ISS) to characterize fibril formation of 40-residue amyloid β (Aβ(1-40)) under microgravity conditions. Our comparative analyses revealed that the Aβ(1-40) fibrilization progresses much more slowly on the ISS than on the ground, similarly to protein crystallization. Furthermore, microgravity promoted the formation of distinct morphologies of Aβ(1-40) fibrils. Our findings demonstrate that the ISS provides an ideal experimental environment for detailed investigations of amyloid formation mechanisms by eliminating the conventionally uncontrollable factors derived from gravity.

Substantiating the Logistics Chain Structure While Servicing the Flow of Requests for Road Transport Deliveries

The selection of the delivery scheme is one of the most complicated problems and the results of its solution condition the sustainable development of the whole market of transportation services. Freight forwarders should consider numerous random parameters characterizing demand and technological processes to choose the proper structure of the logistics chain. The paper aims to propose a method for choosing the logistics chain structure, based on the analysis of the total expenses as a function from the demand parameters characterizing stochastic variables of the consignment weight, the delivery distance, and the time interval between the requests in the flow of queries for cargo delivery. Four basic logistics chain structures, widely used on road transport, are described to demonstrate the selection process. The areas of the most efficient use of the logistics chain structures can be defined for the flow of requests for cargo deliveries. The paper shows such areas on the example of goods delivery by automobile transport. Determining the areas of the most efficient use of the specific logistics chain structures contributes to the effective choice of correct delivery variants by freight forwarders.

Recovery of a Compressed Sensing CT Image Using a Smooth Re-weighted Function- Regularized Least-Squares Algorithm

It is challenging to recover the required compressed CT (Computed Tomography, CT) image, which is got by transferred through the internet or is stored in a signal library after being compressed. We present a recovery method for compressed sensing CT images. At present, minimizing 0-norm, 1-norm and p-norm is used to recover compressed sensing signals. However, sometimes 0-norm is an NP problem, 1-norm has no solution in theory and p-norm is not a convex function. We introduce a recovery method of compressed sensing signal based on regularized smooth convex optimization. In order to avoid solving the non-convex optimization problems and no solution condition, a convex function is designed as the objective function of optimization to fit 0-norm of signal and a fast iterative shrinkage-thresholding algorithm is proposed to find solution with the convergence speed is quadratic convergence. Experimental results show that our method has a sound recovery effect and is well suitable for processing big data of compressed CT images.

A New Proof for Global Convergence of a Smoothing Homotopy Method for the Nonlinear Complementarity Problem

In this paper, we propose a new proof for smoothing homotopy method based on the Fischer–Burmeister function to solve the nonlinear complementarity problem under a nonmonotone solution condition. Under this assumption condition imposed on the defined mapping [Formula: see text], global convergence of a smooth curve determined by the referred homotopy equation is established for almost all initial points in [Formula: see text] and it is actually regarded as an interior point method. Besides, if the initial point is expanded to [Formula: see text], the global convergence of the homotopy method is ensured under a similar condition. The numerical results are reported and illustrate that the method is efficient for some nonlinear complementarity problems.

Foliar Application: A Thriving and Flourishing Domain in Agriculture

Foliar Application seems to be an upcoming and ongoing research area especially in the field of agriculture. This is been in practice in various parts of the world and proved its positive results in its field [1,2]. Foliar application can be explained as spraying the suitable fertilizer solution (condition is, that it should be water soluble) on the surface of the leaves of growing plants [3]. This practice not only saves quantity of fertilizer used but also improves the uptake of a particular micronutrient by the crops and boosts the yield too. Interaction between crop’s genetic potential and the environment in which it grows is detrimental for the yield of a crop [4]. Soil application of nitrogen is a conventional method to supply nitrogen to plants and for improvement in any field adhering to the old ways will not be a better option [4]. In some instances, the availability of urea becomes inadequate for the farmers at sowing time. In such situation the foliar application of plant nutrient is effective and economical for some crops [5]. It has been shown in some studies that uptake of micronutrients directly from plants is more rapid and quicker for better results in yields than soil application[1]. As mentioned above, that the fertilizer should be water soluble for foliar spray and moreover, it should also be noted that the particular crop plant also should be suitable for aerial spray. The best results of foliar application also depends on the soil condition as if soil conditions are unfavourable when micronutrients are needed, it may be desirable to make foliar applications of the plant nutrients