Identification and Quantification of Phthalates in Polyethylene Terephthalate (PET) Water Bottles Produced In the UAE

This thesis highlights the criticality of phthalate esters (PEs), widely used in plastic molding and possessing carcinogenetic and toxicological effects. The thesis aims to assess the presence and abundance of these compounds in polyethylene terephthalate (PET) bottled water produced in the UAE. The thesis tests for 6 types of PEs (dimethyl phthalate (DMP), diethyl phthalate (DEP), diisobutyl phthalate (DiBP), dibutyl phthalate (DBP), butylbenzyl phthalate (BBP) and Di(2-ethylhexyl) phthalate (DEHP) in widely used bottled water brands produced in the UAE. 126 bottled water samples were extracted by liquid-liquid extraction using petroleum ether, followed by analysis of the target compounds using Gas Chromatography-Mass Spectrometry, with a limit of detection that ranges between 0.07 and 0.55 μg/L. The study examined the impact of several parameters on leaching of PEs to bottled water contents including bottle brand, elevated temperature, sunlight exposure, storage time and bottle reuse. It also underlined the harmfulness of the PEs concentration on human health, with details about the commonly enforced regulations on these compounds in bottled water, both worldwide and in the UAE. The only found PE was DiBP with an average concentration ranging between 0.6 and 2.6 μg/L. Moreover, none of the tested parameters showed a clear effect on leaching of PEs to water. Risk analysis was done based on the maximum detected DiBP (3.5 μg/L) and the limits of quantification for all other PEs. No substantial risk was observed. It is concluded that UAE bottled water is safe for drinking from PE leaching perspective. However, it is recommended that extra care should be given to PET bottle recycling; which was used for bottling products other than water as bottle source is suspected to be the reason behind any found PEs in PET bottled water all over the world, considering the fact that PEs are not used in the synthesis of PET plastic. It is also suggested to test water bottles during different steps of the bottling process, to identify the actual sources of PEs, which may not be the PET bottles. Finally, it is vital to do a comprehensive risk analysis to estimate the risk of cumulative exposure to PEs through different channels

Insights into the antioxidative potentials of plants and skin

This thesis has been started by the characterisation of specific plants formulation ‘’PlantsCrystals’’ regarding the antioxidant capacity and size analysis. After that, and using the same principle along with skin analysing techniques, the research is concluded by presenting a novel ex-vivo model to assess the skin's oxidative state using ORAC assay and tape striping method. The developed model has been validated,standardised and then utilised for multiple applications. The employed methodology included multiple antioxidant estimation assays, such as flavonoid and carotenoid content determination, Folin Ciocalteu, DPPH and ORAC assays. Furthermore, ORAC assay, tape stripping and the multi-probe adapter MPA 10 device were the main protocols that were used to develop and assess the porcine ex-vivo skin model.Validation was done by the employment of the preliminary skin samples, afterwards, it was tested on a larger sample size using fresh porcine skin in a controlled lab climate. The numerical values of the antioxidant skin barrier were determined and expressed as the intrinsic AOC. Later, several treatments were applied and significant findings were obtained, as our model was able to detect the changes accurately in a good agreement with the reported data. The most common antioxidative agentsin the cosmetics market were included as treatment agents: ascorbic acid, vitamin E, CoQ10 and ascorbyl palmitate, and their impact on the skin was investigated. In addition to the studies using the main pro-oxidative agent: UV radiation. Moreover, combined treatments were applied aiming to explore the potentials and the limits of this model, and interestingly, it proved its capability to reflect the net effect of multiple factors on the skin antioxidant barrier. Unlimited practice can be applied using the model suggested in this thesis, in order to predict the impact of any kind of single or combined treatment on the skin, without the need to analyse the individual oxidative markers or the use of sophisticated devices. Other relevant investigations have also been demonstrated in the current work, including the study on the novel PlantCrystals which was acting as the backbone of the later studies, mainly through the optimization and the validation of the AOC assays. In addition to the determination of the biophysical properties of intact and impaired porcine skin which was an important knowledge about the porcine ex-vivo model. Therefore, this thesis is presenting a rapid, sustained, non-invasive, versatile, time- and cost-effective model to investigate the skin’s oxidative state. Furthermore, it is revealing, for the first time, the mean values of the intrinsic AOC and the biophysical properties of the ex-vivoporcine skin. Enormous research ideas can be recommended to be done based on the studies of the current work, initially on the impaired skin, including the utilising of the impaired skin model, the investigation of its iAOC and the treatment impact by applying anti- and pro-oxidative agents. Moreover, the model at this point is ready to be applied to living animals and/or human volunteers, to be part of the safety and efficacy pre-marking studies of the cosmeceutical formulations. This step is highly applicable, as we implied a simple and non-invasive procedure that has been used extensively with good acceptability

Women in STEM: Gender Biases and Employment

This main focus of this paper is to reduce the gap between women engagement in undergraduate and career level trends in STEM fields. The literature explored points to the major influence of sociocultural factors in the gender gap at the employment level. Therefore, this study examined possible success factors for solutions to this disparity specifically at the workplace. The findings showed that the implicit gender biases programs became more effective when they enforced experiential learning and occurred at appropriate durations. It was also found that the hiring phases could be more gender balanced using language and application screening tools along with objective assessment replacing interviews. Finally, recommendations regarding workplace policy reformations, bias training programs, and fairer hiring processes are proposed for the context of Egypt

Investigating Preservice Teachers’ Self-Efficacy and Motivation to Teach English Language Learners (ELLs)

This study investigated preservice teachers’ self-efficacy and attitude in working with ELLs in Arkansas. The investigator employed a within-subject design to examine the interrelationships among social cognitive variables (self-efficacy, motivation, and teachers’ preparation programs) and their role in predicting preservice teachers' confidence to teach ELLs in their future classrooms. The main finding of this study is that preservice teachers who are attending educational programs have high-levels of motivation and self-efficacy to work with ELLs in Arkansas. Furthermore, the results of this study revealed that preservice teachers show a strong and positive correlation between their level of confidence to engage ELLs in class activities, to create instructional strategies tailored for ELLs, and to manage ELLs classroom environment. Finally, the results of this study found that speaking a second-language and the level of intrinsic motivation are significant predictors of preservice teachers’ self-efficacy to work with ELLs in their future classrooms. In general, these results are consistent with previous findings produced in the context of preservice and in- service teachers

The association between personality, coping and depressive symptoms in adult patients with chronic pain

As a rising concern in the medical and mental health fields, this study aims to examine predictors of depressive symptoms in a sample of Egyptian chronic pain patients in terms of coping styles and personality traits. Patients with chronic pain are believed to experience different stressors which include, but are not limited to, pain, disability, reduced productivity and financial difficulties. Such factors, in addition to various psychosocial factors, constitute the disease burden of chronic pain. This study examines the degree to which coping styles and personality traits can influence the disease outcome in terms of comorbid depressive symptoms. A total of 98 (50 patients with fibromyalgia and 48 patients with rheumatoid arthritis) patients were interviewed and were assessed in terms of their coping styles, personality profile and severity of depressive symptoms. Results show a high prevalence of depressive symptoms and suggest passive coping, high neuroticism, low extraversion, unmarried status and more years of education. to be moderate predictors of the severity of chronic pain. Findings of this study shed light on the significance of the psychological aspects of chronic pain conditions and may help in designing liaison interventions for the management of secondary and comorbid depressive symptoms

Reading the Mind in the Eyes: Theory of Mind in Acute Psychosis and Schizophrenia

Background: The extant literature indicates that patients with acute psychosis or schizophrenia, as well as nonpsychotic first-degree relatives of patients with schizophrenia, all exhibit “Theory of Mind” (TOM) impairments. Objective: To assess TOM functioning and identify its correlates among a sample of patients with acute psychosis, schizophrenia and healthy controls. Methods: Case control study conducted on 20 patients with acute psychosis, 40 patients with schizophrenia and 60 healthy control volunteers. Patients admitted at Okasha Institute of Psychiatry, Ain Shams University Hospitals, diagnosed using the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I). Severity of symptoms assessed by the Scale for the Assessment of Positive Symptoms and the Scale for the Assessment of Negative Symptoms, while volunteers were assessed by General health questionnaire. All groups were assessed by Reading the mind in the eyes test (RMET). Results: There was significant difference between patients with schizophrenia who scored worse at the RMET than patients with acute psychosis while both have TOM deficit in comparison with the control group. No significant correlation between age or gender in all the three groups and their TOM functioning. There was significant negative correlation between duration of illness of patients with schizophrenia and their TOM functioning. In patients with acute psychosis group, negative symptoms were negatively correlated with the TOM functioning, while in patients with schizophrenia group positive and negative symptoms were negatively correlated with their TOM functioning

Information processing effects of accounting consistency: Evidence from Egypt

Using path analysis, this study investigates the direct and indirect effect of accounting consistency and accounting-based earnings quality proxy on market synchronicity of the Egyptian listed firms. We firstly examine how time-series accounting consistency achieves earnings quality. We find a significant association between time series accounting consistency and lower variation of accruals residuals. We also examine the direct impact of accruals quality on stock returns synchronicity. We find a significant association between lower variation of accruals residuals and higher stock returns synchronicity.  Finally we examine the direct and indirect impact of accounting consistency on market synchronicity. We find that the consistent use of accounting policies can achieve market synchronicity only after achieving earnings quality. Our findings indicate that earnings quality increases the effect of time series accounting consistency on achieving stock returns synchronicity.  &nbsp

FPGA Implementation of Sphere Detector for Spatial Multiplexing MIMO System

Multiple Input Multiple Output (MIMO (techniquesuse multiple antennas at both transmitter and receiver forincreasing the channel reliability and enhancing the spectralefficiency of wireless communication system.MIMO Spatial Multiplexing (SM) is a technology that can increase the channelcapacity without additional spectral resources. The implementation of MIMO detection techniques become a difficult missionas the computational complexity increases with the number oftransmitting antenna and constellation size. So designing detection techniques that can recover transmitted signals from SpatialMultiplexing (SM) MIMO with reduced complexity and highperformance is challenging. In this survey, the general model ofMIMO communication system is presented in addition to multipleMIMO Spatial Multiplexing (SM) detection techniques. These detection techniques are divided into different categories, such as linear detection, Non-linear detection and tree-search detection.Detailed discussions on the advantages and disadvantages of each detection algorithm are introduced. Hardware implementation of Sphere Decoder (SD) algorithm using VHDL/FPGA is alsopresente

Preparation, structural characterization, antimicrobial and anticancer activities, DFT and molecular docking studies of a nano ferrocenyl Schiff base and its metal complexes

1319-1337An organometallic Schiff base (2-(1-((4-aminopyridin-3-yl)imino)ethyl)cyclopenta-2,4-dien-1-yl) (cyclopenta-2,4-dien-1-yl)iron (L) and eight transition metal complexes have been prepared by reacting 3,4-diaminopyridine with 2-acetylferrocene in 1:1 molar ratio for ligand formation and by reacting Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) chlorides with ligand in 1:1 molar ratio for complexes formation. All prepared compounds have been characterized by using elemental analysis (C, H, N, M), molar conductance, IR, UV-Vis, 1H-NMR, SEM and mass spectral analysis. Also, their TG and DTG behaviors have been studied. All complexes have an octahedral structure. The ligand coordinated to the metal ions through the nitrogen atoms of azomethine and amino groups. In addition, computational studies of the synthesized Schiff base ligand have been carried out by the DFT/B3LYP method. The antimicrobial activities of the ligand and its metal complexes have been studied by using different bacterial species [Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Salmonella typhimurium] and fungal species included [Aspergillus fumigatus and Candida albicans]. Moreover, the prepared compounds have been evaluated for anticancer activities against breast cancer (MCF-7) and normal melanocytes (HFB-4) cell lines. Docking studies have been used to determine the probable binding mode between the ligand and its Cd(II) complex with the active site of 3HB5, 2HQ6 and 1GS4 receptors

FACTORS AFFECTING MALAYSIAN INTERNATIONAL HIGH SCHOOL STUDENTS’ PERFORMANCE: THE MODERATING EFFECT OF TRANSFORMATIONAL LEADERSHIP

Purpose of the study: This study intends to scrutinize the factors affecting Malaysian international high school students’ academic performance. Methodology: 117 responses were collected randomly using a questionnaire. The data were analyzed using Partial Least Square (PLS) Main Findings: The findings revealed that future goals as the most crucial factor besides peers’ support, teachers’ support and self-efficacy. Furthermore, it was also disclosed that TL moderated only the self-efficacy on Academic Performance Applications of this study: The study can be used in the context of international high school field or any educational institution as academic performance is a very broad issue discussed in the educational setting Novelty/Originality of this study: Students’ academic performance (AP) is a crucial issue for parents, schools, researchers, and governments. A number of past studies have highlighted the local university students’ AP with less attention given to the performance of international high school students. Thus, this study provides insights pertaining to international high school student