Sana'a University Journal of Applied Sciences and Technology 

Exposure of valuable assets of Yemen banking sector to various attacks and threats may violate the privacy, confidentiality, integrity and accessibility (availability) of their data, information or computer systems resulting in financial and valuable loss. Such a violation may adversely affect the continuity of the business and the competitive advantages they seek to achieve. The objective of this paper is to evaluate the current security performance of banking systems in Yemen and to introduce a framework for improving information security management based on the ISO 27002-2013 benchmark and standards. The proposed framework includes important security factors which are people, technology and process. IBM SPSS AMOS is applied for testing framework hypothesis on complex variable relationships and gain new insight. Such framework shows that the process variable has obtained the most direct positive effect on improving information security management system with value (0.990), while the technology variable has obtained the second direct positive effect on improving the information security management system with value (0.930). Finally, the people variable has obtained the least direct positive effect on improving the information security management system with value (0.740). The research methodology includes: data collection, data analysis, reliability testing and computing results. The model validated and compared with other similar models available in the literature and the results were in valid range. Also, the research hypotheses were significant and deferent results of the proposed model were very promising.

Jatropha curcas and Euphorbia Cactus Ehrenb plants which belonging to Euphorbiaceae family is employed to cure different infections in traditional folklore medicine. Antioxidant activity and total phenol contents (TPCs) for latex of this two plants were analyzed and examined its antimicrobial effect. Both plants showed high antioxidant activity and highly phenolic contents. Positive correlation between antioxidant activity and total phenol has been noted. Jatropha curcas latex demonstrated significant inhibition against the test microorganisms.

A new, easy, fast, and cost-effective simultaneous spectrophotometric method for determining the combined concentration of spiramycin and metronidazole in tablet pharmaceutical formulations was developed and proposed. The suggested method was validated using two chemometric techniques, namely partial least square regression (PLS) and principal component regression (PCR). The significance of the proposed method is that pretreatment or separation steps are not required. Various drug concentrations and instrumental spectra of 25 mixed solutions of spiramycin and metronidazole were used for model design and validation. The UV analysis of the prepared mixtures was recorded with respect to a selected solvent blank in the wavelength range of 200–375 nm. The digitized absorbance was sampled at 0.2 nm intervals. The R² values of 1 and 0.9998 assigned for the PLS of spiramycin and metronidazole, and those of 0.9991 and 0.9998 for the PCR of spiramycin and metronidazole, respectively, exhibited greater prediction efficiencies. The results were statistically compared to those of the HPLC reference method. The statistical comparison between the recommended (PLS and PCR) and reference HPLC method did not find any appreciable variations in accuracy or precision. The suggested approach is simple, effective, and trustworthy enough to be employed as an alternative analytical method for quality control of drug analysis in the pharmaceutical industry.

TiO₂ NPs powder (titanium oxide nanoparticles powder) is synthesized via anodization in 0.7 M HClO₄ is annealed in N₂ at 450°C for 3 hrs to obtain the TiO₂ NPs -N₂ powder as catalyst support to which Au is loaded via photodeposition technique using tetrachloroauric acid (HAuCl₄) and isopropanol as a sacrificial donor. The physicochemical characterizations of TiO₂ NPs arrays powder were performed by transmission electron microscopy (TEM). The TEM image suggested that Au nanoparticles were circular and there was a tendency of agglomerations. The electro-catalytic activity of Au NPs/TiO₂-NTs-N₂ catalysts in ferrocyanide system , KOH ,and H₂SO₄ electro-oxidation was examined by cyclic voltammetry (CV) and contrasted with a financially accessible polycrystalline gold electrode. Au-TiO₂ NPs-N₂ powder electrode catalyst displays a strikingly high electrocatalytic activity in KOH and H₂SO₄ solutions. The results indicate Au NPs/TiO₂-NTs-N₂ catalysts as a promising support material improve the excellent electro-catalytic activity for acidic and basic oxidation.

Biosynthesis of zinc sulfide (ZnS) nanoparticles (NPs) using plant extracts is an alternative method to traditional chemical route. In this study, ZnS-NPs was synthesized via two different routes: (i) bio-based method  using leaf extract of Plectranthus barbatus as a capping agent and (ii) using the chemical co-precipitation route as a capping–free method. The effect of synthesis routes on the structural, morphological, and optical properties of the prepared NPs was analyzed. The obtained ZnS-NPs was characterized using UV-Visible, FTIR, XRD, and SEM. According to XRD analysis, the average crystallite size were found to be 2.259 and 3.080 nm for chemically and bio-synthesized ZnS, respectively; while SEM revealed aggregated NPs to be counted. Additionally, the optical energy bandgap were 3.82 and 3.73 eV of the samples synthesized via chemical and green methods, respectively. The obtained results indicates that ZnS-NPs prepared via the capping–free chemical route is is more favored, in term of its morphological and optical properties, compared to the sample prepared by green method.

Mosquitoes are the most important medical insect, that transmits diseases, such as dengue fever and malaria. The biological effects of new Organophosphorus Schiff base compounds (2-Furalidenediphenylphosphate-1-phenylsemicarbazide OPSL₁) and 2-methoxybenzalidenediphenylphosphate-1-phenylsemicarbazide OPSL₂) against the mosquito larvae of Aedes aegypti was evaluated at different concentrations using WHO standard susceptibility test with some modifications. A laboratory bioassay was conducted to assess the larvicidal activity under controlled laboratory conditions, late 3rd or early 4th instar larvae were exposed to various concentrations – ranging from 150 ppm to 1200 ppm of the tested compounds. Mortalities were observed to increase with the increase in concentrations. The results showed that OPSL₂ revealed significantly high activity against   Ae. aegypti  with (LC50 = 600.6 ppm) compared to the  OPSL₁, with LC50 = 642.9 ppm respectively. Further investigations would be required to evaluate the new active Organophosphorus compounds responsible for larvicidal efficacy in the future.

Modulated ion acoustic wavepackets have been investigated in a multi-component, dense plasma containing degenerate electrons/positrons, and positive/negative ions. The electrons and positrons assumed to be followed Thomas-Fermi distribution, while the ions considered to be classic. Employing a multi-scale perturbation technique, the nonlinear Schrödinger equation is derived. The criteria for the occurrence of modulational instability of the modulated ion acoustic waves are analyzed. The influences of plasma parameters on the modulational instability and its growth rate have been discussed. The envelope solitons have been discussed as well. The results showed that both modulationally unstable domain and stable domain can be found, depending on the plasma parameters. It is also found that the width of the envelop solitons are significantly modified by related plasma parameters. The present results will be useful in understanding the conditions for modulational instability of ion acoustic waves which are relevant to both space and laboratory dense plasmas.

The nonlinear cylindrical dust ion acoustic waves are studied in a collisional unmagnetized dense dusty plasma medium containing inertialess degenerated electrons and positrons, fluid ions, negatively charged dust fluid and neutrals in the background, including exchange-correlation effects of both electrons and positrons. Employing the reductive perturbation method, the damped Kadomstev–Petviashvili equation is derived in the framework of two-dimensional cylindrical geometry. An approximate analytical solution of this equation is also discussed. The quantum and geometrical effects on the dust ion acoustic waves have been investigated. It is found that the dust ion acoustic wave is modified by quantum diffraction, Fermi statistics and exchange-correlation potential. Moreover, it has been found that the nebulon structures of quantum dust ions acoustic wave are formed due to the Cartesian geometry and the transverse perturbation. It is also observed that the nebulon structure is significantly modified by the exchange-correlation effects.

 The Ligand was synthesized  by  condensation of Indol 3-hydroxy aldehyde, Glycine and Hydrazine hydrate. The reaction of the ligand  with  ions (Co^II, Ni^II and Cu^II ions) yielded complexes, these compounds were characterized by physical and spectroscopic techniques. The conductivity showed a non-electrolytic nature for these compounds. The  elemental  analysis  indicated  the  ligand  to metal  ratio  as  1:1  with  general molecular  formula M(L)(H₂O)_nCl₂ (L=ligand; M=metal ions. IR data showed the ligand coordinated to the metal ion via azomethine nitrogen and amine of hydrazide in addition to the amine of indol ring with Cu^ΙΙ. The spectral and magnetic studies of the complexes showed that octahedral geometry for Co^ΙΙ and Ni^ΙΙ while for Cu^ΙΙ distorted octahedral geometry. The particle size and strain of these compounds have been discussed using X-ray diffraction. The antioxidant study for ligand proved to be a good antioxidant. The compounds have been evaluated for their antimicrobial activity against various organisms.

In the current study, w-type BNF-NPs synthesis via ceramic method.the effects of zinc ions doping on the physical properties of BNF-NPs were analyzed. The formation of BNF-NPs  emphasized by XRD, FTIR, UV-Visible spectroscopy and electrical conductivity measurement. The phases structure , crysttallite size and lattice  parameters wrere evaluated using XRD results.  Hexagonal structure with a single phase apeares, the average grain size was found to be  in Nano scale from 32 to 34 nm, while the lattice parameters increased slolly as  the doping concentration of zinc ions increases. The spectra of  FTIR  showed main absorption  bands which confirmed formation of hexagonal ferrite phase. UV-VIS analysis was also performed and found that the band gaps were in the semiconducting region and increased with increasing zinc concentration. The AC conductivity of the samples decreased with increasing zinc content and showed a dependence on  the frequency and temperature. Additionally, as frequency increase the σac conductivity showed dispersion that decreased as temperature increased.dispersion decreases as the temperature increases.