Investigating the relevance of Environmental Kuznets curve hypothesis in Saudi Arabia: towards energy efficiency and minimal carbon dioxide emission

Clean Technologies and Environmental Policy - The Saudi economy is driven by the energy sector which mainly derived from petroleum-based resources. Besides export, the Kingdom’s consumption...     

Establishment of a standard reference material (SRM) herbal DNA barcode library of Vitex negundo L. (lagundi) for quality control measures

The majority of the population in the Philippines relies on herbal products as their primary source for their healthcare needs. After the recognition of Vitex negundo L. (lagundi) as an important and effective alternative medicine for cough, sore throat, asthma and fever by the Philippine Department of Health (DOH), there was an increase in the production of lagundi-based herbal products in the form of teas, capsules and syrups. The efficiency of these products is greatly reliant on the use of authentic plant material, and to this day no standard protocol has been established to authenticate plant materials. DNA barcoding offers a quick and reliable species authentication tool, but its application to plant material has been less successful due to (1) lack of a standard DNA barcoding loci in plants and (2) poor DNA yield from powderised plant products. This study reports the successful application of DNA barcoding in the authentication of five V. negundo herbal products sold in the Philippines. Also, the first standard reference material (SRM) herbal library for the recognition of authentic V. negundo samples was established using 42 gene accessions of ITS, psbA-trnH and matK barcoding loci. Authentication of the herbal products utilised the SRM following the BLASTn and maximum-likelihood (ML) tree construction criterion. Barcode sequences were retrieved for ITS and psbA-trnH of all products tested and the results of the study revealed that only one out of five herbal products satisfied both BLASTn and ML criterion and was considered to contain authentic V. negundo. The results prompt the urgent need to utilise DNA barcoding in authenticating herbal products available in the Philippine market. Authentication of these products will secure consumer health by preventing the negative effects of adulteration, substitution and contamination.     

A novel countermeasure technique for reactive jamming attack in internet of things

Multimedia Tools and Applications - In recent years, Internet of Things (IoT) has attracted significant attention because of its wide range of applications in various domains. However, security is...     

Synthesis of hierarchical nanoporous HY zeolites from activated kaolin,a central composite design optimization study

In this article, we investigated the optimum formulation towards synthesis of hierarchical nanoporous HY zeolites from acid activate kaolin. A central composite design (CCD) helped to examine the influence of aging (X₁), crystallization (X₂) and NaOH solution to kaolin ratio (X₃) on crystallinity (C%), specific surface area (SSA) and hierarchical factor (HF). From the analysis of variance (ANOVA), we deduced that all the process variables show statistical significance towards obtaining high C% and SSA while only X₃ is statistically significant for optimal HF. The effectiveness of models was further evaluated using margin of error and tolerance interval. The Optimum formulation for this hierarchical nanoporous HY zeolite was 43.60, 64.23 and 6.97 for X₁, X₂, and X₃, respectively. The developed models show that X₃ is the most statistically significant variable because it has the highest coefficient and the lowest p-value in the entire model. These results give instrumental insight into the synthesis of hierarchical nonporous HY zeolite.