Nanotechnology

The paper aims at giving suggestions for a deterministic approach to investigate possible earthquake prediction and warning. A fundamental contribution can come by observations and physical modeling of earthquake precursors aim at seeing in perspective the phenomenon earthquake within the framework of a unified theory able to explain the causes of its genesis, and the dynamics, rheology, and microphysics of its preparation, occurrence, post-seismic relaxation, and inter-seismic phases. Studies based on combined ground and space observations of earthquake precursors are essential to address the issue. Unfortunately, up to now what is lacking is the demonstration of a causal relationship (with explained physical processes and looking for a correlation) between data gathered simultaneously and continuously by space observations and ground-based measurements. In doing this, modern and/or new methods and technologies have to be adopted to try to solve the problem. Coordinated space and ground-based observations imply available test sites on the Earth surface to correlate ground data, collected by appropriate networks of instruments, with space ones detected on board of Low-Earth-Orbit (LEO) satellites. Moreover, a new strong theoretical scientific effort is necessary to try to understand the physics of the earthquake. Within this framework a few projects and experiments have been carried out on the subject by our team and accompanied by specific theoretical interpretations.

Increasing the safety of the road transportation leads to reducing the costs of road accidents, especially improving the safety of the pedestrians who are the most vulnerable road users. Regarding the new regulations on the pedestrian safety, automakers have recently paid certain attention to the front-end design of the vehicles. The collision of the pedestrian's head to the automotive hood is the main reason for fatal injuries in pedestrian to vehicle impacts. Head Impact Criteria (HIC) measures the possibility of inducing serious injury to the pedestrian's head in collision with the hood. In this paper, a new finite element model has been developed to simulate the collision between headform impactors and five different hoods according to the EEVC WG17 regulation requirements. This model was utilized to compare pedestrian friendliness of four hoods with four new different inner layers including hemispherical, conical, wavy, and the combination of wavy-conical structures to the original hood and the engine parts are modeled as rigid. It is shown that the pedestrian safety has rigorously improved in the new structures with respect to the original one. In the new designs, the entire structure is involved in energy absorption so it leads to the mitigation of head acceleration to a certain level. Finally, the masses of different structures are compared and it is illustrated that the new structures are not much heavier than the original structure. Moreover, the torsional and latch stiffness of the new structures are much better than the original one.

Increasing the safety of the road transportation leads to reducing the costs of road accidents, especially improving the safety of the pedestrians who are the most vulnerable road users. Regarding the new regulations on the pedestrian safety, automakers have recently paid certain attention to the front-end design of the vehicles. The collision of the pedestrian's head to the automotive hood is the main reason for fatal injuries in pedestrian to vehicle impacts. Head Impact Criteria (HIC) measures the possibility of inducing serious injury to the pedestrian's head in collision with the hood. In this paper, a new finite element model has been developed to simulate the collision between headform impactors and five different hoods according to the EEVC WG17 regulation requirements. This model was utilized to compare pedestrian friendliness of four hoods with four new different inner layers including hemispherical, conical, wavy, and the combination of wavy-conical structures to the original hood and the engine parts are modeled as rigid. It is shown that the pedestrian safety has rigorously improved in the new structures with respect to the original one. In the new designs, the entire structure is involved in energy absorption so it leads to the mitigation of head acceleration to a certain level. Finally, the masses of different structures are compared and it is illustrated that the new structures are not much heavier than the original structure. Moreover, the torsional and latch stiffness of the new structures are much better than the original one.

Our novel magnetic drug carrier, albumin nanoparticles conjugated magnetite nanoparticles is designed for drug delivery applications. Magnetic nanoparticles are very attractive in pharmaceutical applications due to their high efficiency. As the carrier magnetic part, magnetite nanoparticles were produced by coprecipitation of II and III iron ions in an alkaline solution [1]. Their surface was then modified by glycine which has a carboxyl functional group. BSA nanoparticles were simultaneously synthesized by desolvation method [2]. In order to form a covalent bond between amine groups of albumin nanoparticles and carboxyl groups on the surface of iron oxide nanoparticles, they were mixed in an aqueous solution for a predetermined time. The obtained nanoparticles were characterized by XRD, SEM, FTIR and VSM studies. Magnetic nanoparticles were spherical shaped with 55 nm average size (Fig. 1). The formation of C-N bond between the amino groups of the protein and the carboxyl groups on...

New multilayered albumin/silica/iron oxide nanobiohybrid particles was synthesized and characterized. • Silica shell preserves magnetic nanoparticles core while albumin shell improves the biocompatibility. • The superparamagnetic behavior of synthesized nanobiohybrid particles is promising for biomedical applications.

Design of new multifunctional nanosystems to integrate diagnostic and therapeutic functions is a major area of interest in the field of nanobiotechnology and nanomedicine. In this study, application of a new magnetic multilayered nanobiohybrid system composed of magnetite nanoparticles, silica, and albumin as a theranostic agent was investigated. Once the clusters of magnetite nanoparticles were coated with a silica shell, bovine serum albumin was conjugated to the surface of activated amine-MS particles (BMS). Afterwards, a curcuminloaded albumin shell was formed on BMS particles (CBBMS). The curcumin loading capacity and efficiency of the nanobiohybrid particles were 93 ± 6 (mg drug/g particles) and 24 ± 1.7 (wt%), respectively. A sustained release profile was observed for the curcumin in PBS which followed the first-order kinetic model. Cytotoxicity evaluation of CBBMS showed a striking reduced IC 50 value (9.9 μM) in comparison to that of the free curcumin (16.2 μM), tested on SH-SY5Y cells using MTT assay. Finally, the in vitro relaxivity experiments indicated a high transverse relaxivity (r 2) of 369.7 mM −1 s −1 for the superparamagnetic nanobiohybrid particles in magnetic resonance imaging (MRI) tests. The obtained results in drug delivery and MRI tests recommend the as-prepared multilayered nanobiohybrid particles as an efficient and suitable system for theranostic applications.

In this work, the importance of the size and concentration of binding sites in mesoporous nanostructures on their performance for protein delivery is reported. Various types of carboxyl-functionalized mesoporous silica (MS) nanoparticles, i.e., SA(x)-MS, PA1(x)-MS and PA2(x)-MS, where x = 5, 10, 15, 20 and 30 mg, were synthesized by using succinic anhydride (SA) and polyacrylic acid with two molecular weights (i.e., 1800 (PA1) and 100000 (PA2)), respectively. The particles were thoroughly characterized by TGA, FTIR, STEM and zeta potential measurement techniques and then, their biomedical performance was investigated by using a model therapeutic protein, lysozyme. The carboxyl functional molecules concentration (C COOH) on the particles was increased as a function of the functional molecules type and quantity in the synthesis reaction environment. The maximum C COOH values were recorded for SA(10)-MS, PA1(15)-MS and PA2(15)-MS, being 827, 1662 and 2137 µmol.g − 1 , respectively. However, SA(10)-MS, PA1(15)-MS and PA2(10)-MS particles led to the highest lysozyme loading yield values of 63.1, 90.0 and 71.5% as well as the loading capacities of 631, 900 and 715 mg.g − 1 , respectively. The controlled lysozyme release rate and some protein conformational changes favored the in vitro antibacterial activity of lysozyme molecules carried by the particles, which followed the order of PA1(15)-MS > PA2(10)-MS > SA(10)-MS.

In this work, the importance of the size and concentration of binding sites in mesoporous nanostructures on their performance for protein delivery is reported. Various types of carboxyl-functionalized mesoporous silica (MS) nanoparticles, i.e., SA(x)-MS, PA1(x)-MS and PA2(x)-MS, where x = 5, 10, 15, 20 and 30 mg, were synthesized by using succinic anhydride (SA) and polyacrylic acid with two molecular weights (i.e., 1800 (PA1) and 100000 (PA2)), respectively. The particles were thoroughly characterized by TGA, FTIR, STEM and zeta potential measurement techniques and then, their biomedical performance was investigated by using a model therapeutic protein, lysozyme. The carboxyl functional molecules concentration (C COOH) on the particles was increased as a function of the functional molecules type and quantity in the synthesis reaction environment. The maximum C COOH values were recorded for SA(10)-MS, PA1(15)-MS and PA2(15)-MS, being 827, 1662 and 2137 µmol.g − 1 , respectively. However, SA(10)-MS, PA1(15)-MS and PA2(10)-MS particles led to the highest lysozyme loading yield values of 63.1, 90.0 and 71.5% as well as the loading capacities of 631, 900 and 715 mg.g − 1 , respectively. The controlled lysozyme release rate and some protein conformational changes favored the in vitro antibacterial activity of lysozyme molecules carried by the particles, which followed the order of PA1(15)-MS > PA2(10)-MS > SA(10)-MS.