Charge Propagation in a Classical Background.

Abstract This thesis advances the understanding of charge propagation in a classical background through the study of the canonical quantisation of a charged particle in an intense laser background and the associated twopoint function. We will clarify how the causal propagator can be extracted. In addition, in this thesis we will provide an interpretation of this propagator in terms of degenerate quantum processes. We show how to use the Feynman diagram technique to build up a perturbative description of the interaction with the laser background. This also includes how multi-pole structures emerge as a perturbative feature. For all orders in perturbation theory we calculate the associated multiple wave-function renormalisations. We use Bessel functions to describe the distortion of the plane wave solutions due to the interaction with the laser. This is done for both a circularly and a linearly polarised laser.The Government of the Kingdom of Saudi Arabia and Ministry of Higher Education from Taibah Universit

Advanced receivers and waveforms for UAV/Aircraft aeronautical communications

Nowadays, several studies are launched for the design of reliable and safe communications systems that introduce Unmanned Aerial Vehicle (UAV), this paves the way for UAV communication systems to play an important role in a lot of applications for non-segregated military and civil airspaces. Until today, rules for integrating commercial UAVs in airspace still need to be defined, the design of secure, highly reliable and cost effective communications systems still a challenging task. This thesis is part of this communication context. Motivated by the rapid growth of UAV quantities and by the new generations of UAVs controlled by satellite, the thesis aims to study the various possible UAV links which connect UAV/aircraft to other communication system components (satellite, terrestrial networks, etc.). Three main links are considered: the Forward link, the Return link and the Mission link. Due to spectrum scarcity and higher concentration in aircraft density, spectral efficiency becomes a crucial parameter for largescale deployment of UAVs. In order to set up a spectrally efficient UAV communication system, a good understanding of transmission channel for each link is indispensable, as well as a judicious choice of the waveform. This thesis begins to study propagation channels for each link: a mutipath channels through radio Line-of-Sight (LOS) links, in a context of using Meduim Altitude Long drones Endurance (MALE) UAVs. The objective of this thesis is to maximize the solutions and the algorithms used for signal reception such as channel estimation and channel equalization. These algorithms will be used to estimate and to equalize the existing muti-path propagation channels. Furthermore, the proposed methods depend on the choosen waveform. Because of the presence of satellite link, in this thesis, we consider two low-papr linear waveforms: classical Single-Carrier (SC) waveform and Extented Weighted Single-Carrier Orthogonal Frequency-Division Multiplexing (EW-SC-OFDM) waveform. channel estimation and channel equalization are performed in the time-domain (SC) or in the frequency-domain (EW-SC-OFDM). UAV architecture envisages the implantation of two antennas placed at wings. These two antennas can be used to increase diversity gain (channel matrix gain). In order to reduce channel equalization complexity, the EWSC- OFDM waveform is proposed and studied in a muti-antennas context, also for the purpose of enhancing UAV endurance and also increasing spectral efficiency, a new modulation technique is considered: Spatial Modulation (SM). In SM, transmit antennas are activated in an alternating manner. The use of EW-SC-OFDM waveform combined to SM technique allows us to propose new modified structures which exploit exces bandwidth to improve antenna bit protection and thus enhancing system performances

Comparing the effects of acupressure at LI4 and BL32 points on intramuscular injection pain

Introduction The effectiveness of some acupressure techniques in relieving the acute pain of intramuscular injection pain has been assessed in previous studies. However, the effects of acupressure at LI4 point have still remained unknown. The aim of this study was to compare the effects of acupressure at LI4 and BL32 points on intramuscular injection pain. Methods This after-only interventional study was made on 90 women were who referred to the injection unit of the Central Emergency Department, Kashan, Iran, in 2015 for receiving an intramuscular injection of penicillin. The women were randomly allocated to three 30-person groups, namely control, LI4 acupressure, and BL32 acupressure groups. After intramuscular injection of penicillin, the level of intramuscular injection pain of all women was assessed by using a 0–10 visual analog scale. Data were analyzed through doing the Kruskal–Wallis, the Chi-square, and the Fisher's exact tests, and Spearman correlation coefficient. Results The means of pain intensity in the control, LI4 acupressure, and BL32 acupressure groups were 2.76 ± 1.75, 2.33 ± 1.80, and 1.76 ± 2.45, respectively. In other words, the mean pain intensity in the control group was significantly higher than the LI4 and BL32 acupressure groups by 0.43 and 1.0 points, respectively (p = 0.011). Except for educational status, intramuscular injection pain was not significantly correlated with the participants’ other demographic characteristics as well as injection time. Conclusion Acupressure can significantly relieve intramuscular injection pain. This simple, cost-effective, and easily applicable therapy can be used in all healthcare settings for relieving intramuscular injection pain

The History of Nursing Research Methodology in Iran: A Mixed Methods Study

Introduction: Nursing research has dramatic effects on nursing practice. Studying the history of nursing research can provide valuable information about past challenges and future prospects. This study aimed to explore the history of nursing research methodology in Iran.Methods: This was a mixed methods study. In the quantitative part, articles published by nurses in the last four decades were reviewed using a checklist. In the qualitative part, several Iranian nursing doyens and experts were recruited through purposeful and snowball sampling and interviewed through semi-structured interviews. The main focus of the interviews was on the history of nursing research methodology in Iran. Qualitative data were analyzed through conventional content analysis. Finally, the findings of the two parts were merged.Results: The number of nursing articles and journals increased from 39 and one in the 1980s to respectively 461 and thirty in the 2010s. Articles published in the 1980s and the 1990s were mainly related to descriptive researches (91.9% and 88.4%, respectively), while articles in the 2000s were mainly related to quasi-experimental researches (42.8%) and articles in the 2000s were mainly related to quasi-experimental and experimental researches. Qualitative researches become common in the 2010s. The results of the qualitative part were presented based on three era.Conclusions: Nursing research in Iran has had significant improvements in the last three era. Yet, nurses need to make more serious attempts to provide conclusive evidence for nursing practice, improve the Iranians’ health status, and promote the position of nursing in Iran and the position of Iranian nursing in the world

Etude de la nature de la radioactivité gamma dans les roches carbonatées de plate-forme : analyses et interprétations environnementales, diagénétiques et géodynamiques

Mémoire H.S. n°45 de Géologie AlpineIn well-Iogging, values of gamma-activity are measured by scintillometry. A conventional paradigm is to link high y-activity to Potassium (K) and Thorium (Th) isotopes present in clays and to Uranium isotopes present either in detrital sediments ( typically in zircon or monazite minerals) or to sediments rich in organic matter. In shallow-water carbonates platforms, high y-activities are interpreted in the same way. However, in a first y-scintillometer survey of the Gorges du Nan section (subalpine Vercors massif), we found inconsistencies between lithologies and their expected y-responses: the highest radioactive beds do not correspond to high argillaceous or detrital limestones and marls, but to some low content argillaceous or "pure" limestones beds. The aim of this study was to identify the radioactive isotopes associated to different types of carbonates, their localisation, their abundance and their respective contribution to the total gamma response in order to propose a new method for the interpretation of gamma-ray logs in shallow-water carbonates. This study was focused on two intervals: - The first one corresponds to the Ba3 depositional sequence (Upper Barremian) which is composed essentially of limestones. This sequence was studied in the Vercors and Chartreuse subalpine massifs near Grenoble and in the Swiss Jura near Neuchâtel; - The second one corresponds to the "Lower Oritolina marIs" interval. This interval was studied in the Vercors and Chartreuse subalpine massifs near Grenoble, in Spain (Organya basin) and in central Tunisia near Kairouan. We curried out detailed sedimentological, digenetic and isotopic studies of aIl these sections. Oxygen and carbon stable isotopes analyses allowed us to establish some large scale correlations between sections in the French Alps, in the Pyrenees and in central Tunisia. The good correlation between Oxygen and Carbon stable isotopes curves of the Lower Orbitolina marls in aIl the studied areas with the same curves of the Lower Beboulian stratotypic section in Cassis-La Bédoule, proves that the Lower Orbitolina marls are Lower Bedoulian in age. In addition, we curried out detailed y-scintillometry field surveys and performed analyses of selected samples from the Gorges du Nan (Vercors) and Gorges du Frou (Chartreuse) sections by low-Ievel y-spectrometry and ICP-MS. The results confirrn the common idea that K and Th contents are associated to clays and detrital sediments. On the contrary, they show that Uranium contents does not follow the same behavior and are not associated to a specific lithology. In aIl the studied sections we noticed a good correlation between gamma-ray peaks and some key surfaces in sequence stratigraphy (sequence boundaries Sb, mfs and some parasequence boundaries). We noticed also a good correlation between uranium content peaks and the abundance of echinid fragments. In every analyzed samples, isotopes of the uranium decay series are by far the main source of gamma-activity. The contributions of K and of the Th decay series are negligible. Thus the interpretation of gamma-ray logs in shallow water carbonate platform should be revised: rather than a lithological index, it should be used to identify key surfaces in sequence stratigraphy in addition to other diagraphic tools.Lors de l'interprétation des diagraphies de radioactivité des carbonates, les pics de gamma-ray sont très souvent assimilés à des pics d'argilosité. Les faibles radioactivités sont, quant à elles, attribuées à des niveaux calcaires très peu marneux et pauvres en matière organique. Toutefois, l'enregistrement de la radioactivité gamma totale à l'aide d'un scintillomètre portable dans les carbonates de la plate-forme urgonienne des environs de Grenoble a révélé l'existence d'anomalies de la radioactivité dans ces roches, notamment la présence de pics importants de la radioactivité dans des niveaux calcaires purs ou très pauvres en minéraux argileux et détritiques. Le but de ce travail a été d'arriver à identifier les éléments radioactifs associés aux différents types de carbonates, leurs localisations, leurs abondances et leurs contributions respectives au signal gamma total enregistré pour mieux comprendre l'origine de la radioactivité dans ces roches, d'une part, et proposer une méthode pour mieux utiliser l'outil gamma-ray pour des interprétations séquentielles et environnementales dans les séries de carbonates de plate-forme, d'autre part. Pour mener à bien ce travail nous avons choisi plusieurs sites d'études, mais nous nous sommes intéressés à deux intervalles bien particuliers : ~ le premier correspond à la séquence de dépôt BA3 (troisième séquence de dépôt du Barrémien supérieur) formée principalement de faciès calcaires. Nous avons étudié cette séquence dans les massifs subalpins septentrionaux des environs de Grenoble et dans le Jura suisse de la région de Neuchâtel, ~ le deuxième correspond à l'intervalle des couches inférieures à orbitolines. Nous avons étudié cet intervalle dans les massifs subalpins septentrionaux aux environs de Grenoble, en Espagne dans le bassin d'Organya et au Jebel Jediri dans la région de Kairouan en Tunisie. Nous avons réalisé une étude sédimentologique et séquentielle très détaillée de l'ensemble des coupes étudiées. L'analyse des isotopes stables du carbone et de l'oxygène nous a permis d'avoir une meilleure idée sur l'histoire et l'évolution diagénétique de ces carbonates, mais aussi de proposer une corrélation à grande échelle entre les différentes zones d'études. La corrélation des courbes isotopiques (& l3 C et &18 O) de l'intervalle des couches inférieures à orbitolines des massifs subalpins septentrionaux et de ses équivalents en Tunisie et en Espagne avec la coupe stratotypique du Bédoulien nous a permis d'apporter un argument de plus pour dater du Bédoulien inférieur cet intervalle des couches inférieures à orbitolines (CIO). Les analyses en spectrométrie gamma d'échantillons prélevés dans les différents faciès carbonatés étudiés, montrent clairement que c'est l'uranium qui est la principale source des émissions gamma dans ces roches et que les variations de la courbe gamma-ray totale est très étroitement liée aux variations des teneurs et de l'activité de cet élément. Des analyses complémentaires en lCP-MS nous ont permis de préciser qu'il existe au moins trois sources de l'uranium dans les carbonates de plate-forme: -l'uranium fixé dans les tests d'échinodermes qui abondent lors des phases d'approfondissement relatif des milieux de dépôt (aux environs des mfs et mfs relatives de paraséquences), -l'uranium qui provient de la circulation des fluides météoriques lors des phases d'émersion et qui se concentre dans les environs des limites de séquences de dépôt et de certaines paraséquences émersives. Nous avons réussi à montrer avec l'ensemble de ces analyses et observations que le gamma-ray ne peut pas être utilisé sans discussion critique comme outil de corrélation lithologique et que son utilisation indépendamment des autres outils diagraphiques peut conduire à corréler des ensembles sédimentaires très différents

Identification of a putative anti-rheumatoid arthritis molecule by virtual screening

Purpose: To propose an improved chemical skeleton whose scaffolds could be used for the design of future thymidylate synthase (TS)-inhibitors against rheumatoid arthritis. Methods: The drug discovery platform, ‘MCULE’, was employed for inhibitor-screening. The ‘methotrexate-interaction site’ in the crystal (PDB ID 5X66) was used as a target. One ‘RO5 violation’ was permitted. A maximum of ‘10 rotatable bonds’ and ‘100 diverse molecules’ were also allowed in the protocol. The ‘threshold similarity cut off’ was 0.7. The input values describing the remaining parameters were kept as ‘default’. The ‘Open Babel Linear Fingerprint’ was used for the analyses of molecular descriptors, followed by ADME-check. Results: 4-(4-Methyl-1-piperazinyl)-2-phenyl[1]benzofuro[3,2-d]pyrimidine corresponding to the MCULE ID-7590816301-0-93 exhibited the overall best binding with TS. The free energy of binding was -8.6 kcal/mol. A total of 17 amino acid residues were significant for the binding interactions. Importantly, 9 residues were common to methotrexate binding. It satisfied pertinent ADME conditions. Conclusion: 4-(4-Methyl-1-piperazinyl)-2-phenyl[1]benzofuro[3,2-d]pyrimidinemay emerge as a potent seed molecule for TS-inhibitor design in the context of rheumatoid arthritis. It has satisfied pertinent ADME features. However, there is need for further wet laboratory validation. Keywords: Anti-rheumatoid arthritis, Inhibitor design, Methotrexate, Seed molecule, Thymidylate synthase, Virtual screenin

Molecular interaction of 4-amino-N’-(benzoyloxy)-N-(2,4- dimethylphenyl)-1,2,5-oxadiazole-3-carboximidamide with the methotrexate binding site of human DHFR, and its implication in rheumatoid arthritis

Purpose: To identify an improved lead molecule for the human dihydrofolate reductase (DHFR) inhibition that ‘sits’ in the same binding cavity as methotrexate by high throughput computationalscreening.Methods: The 3-D structure of the DHFR binding site was examined using ‘CASTp3.0’. Structure based in silico screening of about 5 million drug candidates housed in the MCULE database was performed. The obtained molecule-hits were ranked in accordance with their VINA scores, made to pass through drug-likeness filters, ΔG cut-off criterion, toxicity-checker and finally ‘zero RO5 criterion’.Results: The ‘top molecule’, namely, 4-amino-N'-(benzoyloxy)-N-(2,4-dimethylphenyl)-1,2,5-oxadiazole- 3-carboximidamide, displayed robust binding with human DHFR through 21 amino acid residues (ΔG = - 9.6 kcal/mol) while 10 of these residues were the same as those displayed by ‘methotrexate binding interactions’. It passed through relevant drug screening filters including the ‘Toxicity Checker’.Conclusion: This research work describes the molecular interaction of human DHFR with an improved lead molecule named, 4-amino- N’-(benzoyloxy)-N-(2,4-dimethylphenyl)-1,2,5-oxadiazole-3- carboximidamide, with a ΔG of -9.6 kcal/mol, thus satisfying adequate ADME features for further in vitro and in vivo validation in the context of rheumatoid arthritis. Keywords: Dihydrofolate reductase, In silico screening, Methotrexate, Rheumatoid arthritis, DHF

Sequence analysis of the VSX1 and SOD1 genes in families with Keratoconus and a review of the literature

AbstractObjectiveKeratoconus (KC) is a non-inflammatory disorder of the cornea in which the cornea becomes thin and conical, inducing myopia and irregular astigmatism and resulting in mild to marked impairment of vision. The present study was designed to screen two candidate KC genes to identify pathogenic sequence variants responsible for KC in Saudi families.MethodsPeripheral blood samples from members of five Saudi families with KC from the Northern region were collected. Genomic DNA was isolated, and bidirectional sequencing was performed of all coding exons of VSX1 and SOD1 genes using Sanger sequencing.ResultsAll five of the KC families showed a pattern of autosomal recessive inheritance. Phenotyping of these families was performed by a senior ophthalmologist. Sequence analysis of the VSX1 and SOD1 genes failed to reveal any pathogenic sequence variant that could account for KC in the affected individuals.ConclusionOur failure to detect sequence variants in two of the known KC associated genes triggers an interest in other known KC candidate genes, including miR-184, DOCK9, IL1RN and SLC4A11. Future genotyping with dense SNP arrays followed by exome sequencing in these families will be a useful approach to identify the gene(s) underlying KC in this Saudi cohort, which may be different from those reported elsewhere

The association between hypertension and other cardiovascular risk factors among non-diabetic Saudis adults-A cross sectional study

Population specific associations between cardiovascular disease with various risk factors including pre-hypertension and hypertension were reported. We aimed to investigate the association of higher than optimal blood pressure with measures of dysglycemia, dyslipidemia, and markers of inflammation in non-diabetic Saudi adults hoping to improve current Saudi guidelines to prevent cardiovascular disease. Volunteers were recruited randomly from public healthcare centers in Jeddah. Demographic information, blood pressure (BP), and anthropometric measurements were taken. Fasting blood samples were drawn, then again following 1-hour oral glucose tolerance test. Glycated hemoglobin, fasting plasma glucose (FPG), lipid profile, highly sensitive C- reactive protein, gamma glutamyl transferase, and 1-hour plasma glucose were measured. Complete data was found for 742 men and 592 women. Pre-hypertension was found in 47.2% of men, and 24.7% of women, while 15.1% of men, and 14.6% of women were hypertensive. Means of measured variables differed significantly between normotensive, pre-hypertensive, and hypertensive groups of men and women in gender specific manner. Association between measured variables and elevated BP, and hypertension were assessed using logistic regression models. After adjustment for age, body mass index and waist circumference, elevated blood pressure was associated with elevated triglycerides in men, while hypertension was significantly associated with elevated fasting plasma glucose, total cholesterol, triglycerides, low density lipoprotein- cholesterol, and low high density lipoprotein- cholesterol in men, and elevated triglycerides, and total cholesterol in women. Therefore, it is strongly recommended to measure lipid profile, specifically TG, for all diagnosed pre-hypertensive and hypertensive patients in addition to FPG for men.Peer reviewe