Free Reducing Agent, One Pot, and Two Steps Synthesis of Ag@SiO[2] Core-shells using Microwave Irradiation

In this work a new method for the fabrication of Ag@SiO[2] nanoparticles have been proposed that is completely different from Stober method. Ag nanoparticles were synthesized using microwave irradiation. polyvinylpyrrolidone was used as stabilizer and capping agent, 3-Aminopropyltriethoxysilane as functionalizer of silver particles in fully ethanol solution. The Ag nanoparticles were used subsequently without any subtraction and treatment in the preparation of Ag@SiO[2] core-shell nanoparticles. UV-Vis spectroscopy shows a characteristic plasmon peak at 400 nm and 430 nm for Ag nanoparticles and Ag@SiO[2] coreshells. Transmission electron microscope images show that Ag nanoparticles have the average size of 10 nm. It is also depicted that SiO[2] shell structure was formed uniformly with the average size of 10 nm. The application of 3-Aminopropyltriethoxysilane in the preparation of core-shells yields single Ag core structure

Fast image reconstruction for near-field terahertz imaging with multistatic non-uniform sparse arrays

Conference paper presented at Radar Sensor Technology XXVII, Orlando, FL, USA, 30 April - 5 May, 2023.In this paper, first, the structure of a linear sparse periodic array for two-dimensional scanning is described. Then, based on its characteristics, an algorithm is presented for fast image reconstruction of the scene in a near-field (NF) multistatic terahertz imaging scenario. Although the basis of this algorithm is developed in the Fourier domain, it is compatible with the non-uniform structure of the array and also takes into account the phase deviations caused by multistatic imaging in NF. The performance of the proposed approach is evaluated with numerical data obtained from electromagnetic simulations in FEKO as well as experimental data. The results are discussed in terms of computational time on the central processing unit and graphics processing unit as well as the quality of the reconstructed image.Leverhulme Trust under Research Leadership Award RL-2019-019. The work of Shaoqing Hu is funded by Brunel University London under Research Development Fund LBG194 and 2022/2023 Brunel Research Initiative and Enterprise Fund 12455

Comparison of antimicrobial and wound-healing effects of silver nanoparticle and chlorhexidine mouthwashes: an in vivo study in rabbits

The objective is to formulate a silver nanoparticle mouthwash and then evaluate its antimicrobial and wound-healing effects in rabbit animal models. Microbial samples were collected from the oral cavity of 60 rabbits. Thereafter, standardized wounds were created in the lateral border of the tongue on the right side for all rabbits. After surgery, digital photographs were obtained from the wounds with standardized settings. To characterize the silver nanoparticles used in the synthetic mouthwash, transmission electron microscopy (TEM) and digital light scattering analysis were used. The animal models were then randomly divided into 4 groups: group 1 received 9.80 wt% silver nanoparticle mouthwash; group 2 received all the ingredients of the formulated mouthwash except for silver nanoparticles; group 3 received chlorhexidine 2.0% mouthwash; and the negative control group did not receive any postoperative mouthwash. Microbial samples were collected from oral cavity of the rabbits each day for four postoperative days. Colony-forming unit (CFU) counts were compared post-operatively with the pre-operative counts. In addition, standardized digital photographs were taken each day from the wounds and the area of the wounds was compared in postoperative and pre-operative images. Data were statistically analyzed using one-way ANOVA and repeated measures variance analysis (α = 0.05). TEM revealed spherical morphology of silver nanoparticles and digital light scattering showed an average size of 5 nm and optimal distribution of the nanoparticles. CFU count significantly decreased in groups 1 and 3 (P 0.05). Silver nanoparticle mouthwash possesses favorable antibacterial and wound-healing effects. The formulated 9.80 wt% silver nanoparticle mouthwash with a particle size of 5 nm can be a promising alternative for application after oral surgical procedures

220 GHz Sparse Imaging with Multi-static Aperiodic Array

Research Development Fund of Brunel University London under Grant LBG194

MIMO Coded Generalized Reduced Dimension Fourier Algorithm for 3-D Microwave Imaging

10.13039/501100000275-Leverhulme Trust under Research Leadership Award (Grant Number: RL-2019-019); 10.13039/501100007914-Brunel University London under Research Development Fund (Grant Number: LBG194); 10.13039/501100007914-2022/2023 Brunel Research Initiative and Enterprise Fund (Grant Number: 12455)

Higher Dimensional Dust Cosmological Implications of a Decay Law for Λ\Lambda Term : Expressions for Some Observable Quantities

In this paper we have considered the multidimensional cosmological implications of a decay law for $\Lambda$ term that is proportional to $\beta \frac{\ddot {a}}{a}$, where $\beta$ is a constant and $a$ is the scale factor of RW-space time. We discuss the cosmological consequences of a model for the vanishing pressure for the case $k=0$. It has been observed that such models are compatible with the result of recent observations and cosmological term $\Lambda$ gradually reduces as the universe expands. In this model $\Lambda$ varies as the inverse square of time, which matches its natural units. The proper distance, the luminosity distance-redshift, the angular diameter distance-redshift, and look back time-redshift for the model are presented in the frame work of higher dimensional space time. The model of the Freese {\it et al.} ({\it Nucl. Phys. B} {\bf 287}, 797 (1987)) for $n=2$ is retrieved for the particular choice of $A_{0}$ and also Einstein-de Sitter model is obtained for $A_{0} = {2/3}$. This work has thus generalized to higher dimensions the well-know result in four dimensional space time. It is found that there may be significant difference in principle at least, from the analogous situation in four dimensional space time.Comment: 10 pages, no figure, to be appear in IJMP

A multi-resolution analysis-based approach to accelerate data acquisition for near-field MIMO millimeter-wave imaging

Leverhulme Trust under Research Leadership Award RL-2019-019

Fourier-Based Near-Field Three-Dimensional Image Reconstruction in a Multistatic Imaging Structure Using Dynamic Metasurface Antennas

Brunel University London Research Development Fund (Grant Number: LBG194); 2022/2023 Brunel Research Initiative and Enterprise Fund (Grant Number: 12455); 10.13039/501100000275-Leverhulme Trust (Grant Number: RL-2019-019)

Analgesic and sedative effects of caudal epidural tramadol in dromedary camels

This study aimed to investigate the analgesic efficacy of caudal epidural administration of tramadol in dromedary camels (Camelus dromedarius). A total of 10 dromedary camels of both sexes were se-lected and randomly assigned to one of two groups to receive epidurally either 1 mg/kg or 2 mg/kg of tramadol hydrochloride. The injections were made into the epidural space at first intercoccygeal junc-tion. Using a pinprick method, analgesia was tested. Duration and onset of complete perineal analge-sia were determined. Ataxia and sedation were also assessed and recorded. Clinical parameters in-cluding heart rate, respiratory rate and rectal temperature were measured. The lower dose (1 mg/kg) of tramadol induced analgesia only in the tail but the higher dose produced complete antinociception in the tail, anus and perineum. Analgesia of the hind limbs was not achieved after either doses of tramadol. The mean times to onset and duration of complete analgesia in camels receiving epidural tramadol at a dose of 2 mg/kg were 22±2.55 min and 65±8.66 min, respectively. Various degrees of ataxia occurred in all camels. Mild to deep sedation was observed following both doses. Mean heart rate, respiratory rate, and rectal temperature tended to increase for the first 15 or 30 min after injec-tion. Based on the results of this study, analgesic effects of caudal epidural tramadol were dose de-pendent. Epidural tramadol at a dose of 2 mg/kg would provide suitable postoperative analgesia for various manipulations in the tail, anus and perineum in standing dromedary camels

Fast Processing Approach for Near-Field Terahertz Imaging with Linear Sparse Periodic Array

10.13039/501100000275-Leverhulme Trust (Grant Number: RL-2019-019)