Understanding social media usage by females in Saudi Arabia: a descriptive finding

Recently, Social Media (SM) platforms are not only functioned for entertainment but also for the exchange of information, collaboration and overcoming of cultural boundaries. Social media can provide many opportunities to Saudi females who are faced with many cultural boundaries such as unemployment and segregation between genders. However, the use of SM by Saudi females is still lesser than that of Saudi male. Few studies have yet investigated the involvement of Saudi females in SM. This study was conducted to determine the effects of SM on Saudi females. A comprehensive online survey was conducted and 632 valid responses were collected from Saudi females. Saudi females use SM to spend their spare time or for entertainment, to stay up-to-date with news and current events and to connect with friends and family. The study reveals a low percentage of SM use among Saudi females for business purposes. The finding also show that SM is potential to play a significant role in empowering the life of Saudi females at early age hence more effort should be undertaken to encourage more uptake of SM for business and commerce regardless of gender.Keywords: Social media, Saudi Arabia, females, data screenin

Fear of the Unknown among Normal People, People with Psychological Disorders, and People with Organic Disorders in the Light of Some Demographic Variables

The present paper aimed to determine the fear of the unknown among normal people, people with psychological disorders, and people with organic disorders in the light of some demographic variables. The authors adopted the descriptive-comparative method and developed and applied a three-domain questionnaire to a randomly selected sample of (942) participants. The results showed that the people with psychological disorders suffer from fear of the unknown more than normal people and people with organic disorders at a significance level of (0.05). There were no statistically significant differences between the different categories of psychological disorders (including generalized anxiety disorder, depression, panic attacks, post-traumatic stress disorder, obsessive-compulsive disorder, and phobia) in contrast with the organic diseases, in which cardiac and respiratory diseases were at a greater risk of being afraid of the unknown more than those with diabetes, blood pressure, and thyroid. The paper recommends conducting further studies on the concept of fear of the unknown in the Arab countries and adopting fear of the unknown as a psychological intervention for people with psychological disorders and people with cardiac and respiratory diseases

Impact of free radicals on the electrostatic charging tendency of transformer oils

In this contribution, the influence of free radical concentration on the electrostatic charging tendency (ECT) of aged mineral oils is reported. A free radical reagent, 2,2 diphenyl-1-picrylhydrazyl, is used to assess the relative concentration of free radicals. Prior to the ECT measurement, the oil samples were subjected to various stresses (corona discharges, multiple arcs or local overheating). Different ASTM standards were considered to assess the physicochemical properties before and after stress applications. It is found that free radicals affect the ECT. The theoretical premises that, free radicals may contribute to the ECT, are experimentally confirmed under laboratory conditions. The reason why this information is important is that ECT can significantly affect partial discharge inception in in-service transformers

Formal Verification and Validation of UML 2.0 Sequence Diagrams using Source and Destination of Messages

AbstractA major challenge in software development process is to advance error detection to early phases of the software life cycle. For this purpose, the Verification and Validation (V&V) of UML diagrams play a very important role in detecting flaws at the design phase. It has a distinct importance for software security, where it is crucial to detect security flaws before they can be exploited. This paper presents a formal V&V technique for one of the most popular UML diagrams: sequence diagrams. The proposed approach creates a PROMELA-based model from UML interactions expressed in sequence diagrams, and uses SPIN model checker to simulate the execution and to verify properties written in Linear Temporal Logic (LTL). The whole technique is implemented as an Eclipse plugin, which hides the model-checking formalism from the user. The main contribution of this work is to provide an efficient mechanism to be able to track the execution state of an interaction, which allows designers to write relevant properties involving send/receive events and source/destination of messages using LTL. Another important contribution is the definition of the PROMELA structure that provides a precise semantics of most of the newly UML 2.0 introduced combined fragments, allowing the execution of complex interactions. Finally, we illustrate the benefits of our approach through a security-related case study in a real world scenario

Transionospheric attenuation of 100 kHz radio waves inferred from satellite and ground based observations

International audienceAround fifty LORAN (LOng RAnge Navigation) transmitters in the northern hemisphere currently launch continuously pulsed 100 kHz radio waves into the Earth's atmosphere for marine navigation. It is discovered that the 100 kHz radio waves from the LORAN transmissions can be detected by the DEMETER satellite at an altitude of $660 km above the transmitters. These novel electric field measurements in space enable the determination of the nocturnal transionospheric attenuation by comparison with ground based electric field measurements. The electric field measurements on the satellite indicate that the nocturnal transionospheric attenuation of 100 kHz radio waves from LORAN transmissions is equivalent to a nocturnal subionospheric attenuation of the 100 kHz radio waves at a distance of$7-9 Mm. The radio waves exhibit an average subionospheric attenuation of $5 dB/Mm and it is concluded that the nocturnal transionospheric attenuation of 100 kHz radio waves is$35-45 dB. This result enables future space missions to quantify the intensity of lightning discharges associated with transient luminous events and terrestrial gray flashes

Actions of bisnucleophiles on (E)-3-[3-(2-Hydroxyaryl)-3-oxoprop-1-en-1-yl]chromones: versatile transformations into oxygen-and nitrogen-containing heterocycles

The transformations of (E)-3-[3-(2-hydroxyaryl)-3-oxoprop- 1-en-1-yl]chromones in the presence of methylhydrazine and aromatic bisnucleophiles are described. The reactions generally lead to chromone ring transformation via pyrone ring-opening and heterocyclization to give novel diazoles and (Z)-3-aminomethylenechromanones, respectively. Piperazine catalyzes chromanone ring closure of the starting substrate to afford chromone–chromanone dyads

Synthesis and Ring Transformation of Oxygen and Nitrogen Spiro Bisheterocycles

A facile and rapid access to bridgehead oxygen-and nitrogen-containing spiro bisheterocycles is reported. It involves a one-pot spiro-to-spiro ring transformation of the key spiro[chromanone-hydantoin] compounds into new substituted spiro [hydantoin-diazole], spiro [hydantoin-isoxazole], spiro [hydantoin-diazepine], spiro [hydantoinoxazepine], and spiro [hydantoin-benzodiazepine] upon reaction with appropriate bisnucleophilic agents. The hydantoin cycle is preserved during these chemical reactions affording the spiro bisheterocycles in optimal yields (42-71%). This relevant spiro-to-spiro ring transformation was confirmed by NMR and single-crystal X-ray diffraction studies

A One-Pot Diastereoselective Synthesis of 2-[Aryl(hydroxy)methyl]-6-methyl-2H-furo[3,2-c]pyran-3,4-diones: Crystallographic Evidence for the Furanone Ring Closure

Novel furopyran-3,4-dione-fused heterocycles have been obtained by a one-pot reaction of -brominated dehydroacetic acid and benzaldehydes under organobase conditions. The prepared 2-[aryl(hydroxy)methyl]-6-methyl-2H-furo[3,2-c]pyran-3,4-diones were fully characterized by 2D NMR spectroscopy and supported by single-crystal X-ray analysis to unequivocally prove the furan-3-one five-membered ring-closure mechanism instead of the dihydroflavanon-3-ol six-membered cyclization which has recently been proposed in the literature

1,3-Dicyclo­hexyl­imidazolidine-2,4,5-trione

The title compound, C15H22N2O3, has been isolated as a by-product of an oxidative cleavage of the C—C bond linking two five-membered rings of 1,3-dicyclo­hexyl-5-(3-oxo-2,3-dihydro­benzofuran-2-yl)imidazolidine-2,4-dione. Individual mol­ecular units are engaged in weak C=O⋯C=O inter­actions [O⋯C = 2.814 (10) and 2.871 (11) Å], leading to the formation of supra­molecular chains which close pack, mediated by van der Waals contacts, in the bc plane

One-Pot Synthesis of Novel Highly Functionalized Furan-Based Polyphenolics

Novel, highly functionalized furan-based polyphenolics were prepared. The employed methodology involves a one-pot 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) catalyzed 1,4-conjugate addition of 1,3-dicarbonyl compounds on 3-bromochromones, furan heterocyclization, and chromanone ring opening