Un precinto bilingüe de plomo de la conquista omeya de la península ibérica

This paper presents a hitherto unknown early Arabic-Latin bilingual lead seal depicting a peace pact (muṣālaḥa). The similarities of the Latin signs on one of its faces with those found on a Visigothic monetary issue attributed to the city of Seville, lead us to suggest that this seal could be from the earliest phase of the Umayyad conquest of the Iberian Peninsula, and that it probably alludes to the first peace pact established by Mūsā b. Nuṣayr with that city.Se presenta un sello de plomo bilingüe árabe-latino, hasta ahora desconocido, que representa un pacto de paz (muṣālaḥa). Las similitudes de los signos latinos de una de sus caras con los encontrados en una emisión monetaria visigoda atribuida a la ciudad de Sevilla nos llevan a sugerir que este sello podría ser de la fase más temprana de la conquista omeya de la península ibérica, y que probablemente alude al primer pacto de paz establecido por Mūsā b. Nuṣayr con dicha ciudad

Notas sobre precintos y ponderales. I. Varios precintos de ṣulḥ a nombre de ‘Abd Allāh ibn Mālik: correcciones y una posible atribución. II Adiciones a «Ponderales andalusíes»

In this paper a number of items so far unregistered are added to both the catalogue of lead seals produced during the first period of Islamic Spain, and the catalogue of coin weights related to numismatic issues of different historical periods.En el presente escrito se añaden varias piezas hasta ahora inéditas tanto al corpus de precintos producidos durante el período inicial de al-Andalus, como al de los ponderales relacionados con las emisiones monetarias de épocas diversas en la historia andalusí

The Legal Classification for Transfer of Securities Ownership in the Stock Exchange

The process of securities trading is, in fact, a process of sale and purchase of these securities. These papers, regarded as identical movables, can replace each other if they are of the same type, version, and currency. This is quite common in securities. Regardless of the consideration of the security from identical or valuable movables, the majority of comparative regulations governing the trading of securities on exchanges, including the Iraqi law, have required that the securities be designated and deposited with the market. It is also required from each of the converter and the transferee to hold an investor number in the market before making any transfer of ownership of such securities. This means that the majority of comparative law regulations had made it necessary for the full contract traded securities, the arrangement of the legal effect related to transferring the ownership of securities from the seller to the buyer, and the need to follow certain formalities. Therefore, we conclude that there is no lack of disruption of the impact of the carrier\u27s ownership of securities from the seller to the buyer despite the implementation of orders for buying or selling stocks, but it is the application of general rules in the Iraqi civil law that requires a commitment for ownership transfer. This automatically transmits this right if this was the subject of commitment to something more specific in particular, without prejudice to the rules relating to registration. Therefore, the ownership of securities does not transfer without having met the prescribed formalities according to the law, which is represented by the completion of procedures for clearing, settlement and registration, so there is no way to say disable it

The Potential Anti-Tumor Extract Of Ocimum Basilicum Lamiaceae Towards Colorectal Cancer Via The Angiogenesis Mechanistic Pathway

Angiogenesis is a process of new blood vessel development which can be triggered by inflammation. Both processes play crucial role in colorectal cancer. Natural products that have high level of antioxidants are known to have anti-inflammatory and anti-angiogenic activity and hence could be useful to treat colon cancer. In this work present here, methanolic extracts of 19 plant species of lamiaceae family found in Saudi Arabia were screened for their anti-angiogenic activity to ascertain their potency towards colon cancer. Only six extracts inhibited neovascularization formation by 50% or more, namely Thymbra capitate (Arial part) (97.93±2.63%), Premna resinosa (Stem) (85.03±16.84%), Phlomis viscosa Poir (Arial part) (81.47±22.95%), Salvia samuelssonii (Arial part) (55.69±12.72%), Ocimum basilicum (Leaves) (54.55 ± 4.27%) and Ocimum basilicum (Arial part) (53.99 ± 8.75%). However, methanolic extract of Ocimum basilicum (OB) leaves shown the highest inhibition towards endothelial cells proliferation and migration among other extracts. (OB) leaves were extracted with 70% ethanol (OBL70) at 55 ⁰C, causing a 43% increase in the anti-angiogenic properties compared to methanolic extract. OBL70 was studied in vitro against endothelial cells proliferation, cytotoxicity, migration, invasion and capillary-like structures using MTT, colony formation, scratch, invasion and tube formation assays, respectively

Optimal rotor design of synchronous reluctance machines considering the effect of current angle

The torque density and efficiency of synchronous reluctance machines (SynRMs) are greatly affected by the geometry of the rotor. Hence, an optimal design of the SynRM rotor geometry is highly recommended to achieve optimal performance (i.e., torque density, efficiency, and power factor). This paper studies the impact of considering the current angle as a variable during the optimization process on the resulting optimal geometry of the SynRM rotor. Various cases are analyzed and compared for different ranges of current angles during the optimization process. The analysis is carried out using finite element magnetic simulation. The obtained optimal geometry is prototyped for validation purposes. It is observed that when considering the effect of the current angle during the optimization process, the output power of the optimal geometry is about 3.32% higher than that of a fixed current angle case. In addition, during the optimization process, the case which considers the current angle as a variable has reached the optimal rotor geometry faster than that of a fixed current angle case. Moreover, it is observed that for a fixed current angle case, the torque ripple is affected by the selected value of the current angle. The torque ripple is greatly decreased by about 34.20% with a current angle of 45 degrees compared to a current angle of 56.50 degrees, which was introduced in previous literature

Synchronous reluctance machines : performance evaluation with and without ferrite magnets

Nowadays, a great interest in the efficiency and the cost of electrical machines has been noticed. Therefore, Synchronous Reluctance Motors (SynRMs) have become more attractive alternative for induction and permanent magnet (PM) synchronous machines in several industrial applications. This is because they do not use rare-earth magnets, windings and cages in their rotor. Consequently, the cost and efficiency are improved. Nevertheless, a major problem of the SynRMs is the low power factor. To improve the power factor as well as the torque density and efficiency, the cheap ferrite PM can be inserted in the rotor, resulting in the so called 'PM assisted SynRM'. The rotor design of SynRMs with and without permanent magnets (PMs) has a huge effect on the motor efficiency, torque density and power factor. This paper introduces an evaluation for the performance of SynRMs with and without PMs in terms of efficiency, torque and power factor maps as a consequence of different rotor designs. Three different rotor designs for the same machine stator have been compared. For one machine, the experimental measurements are obtained and the validation of the simulation results are confirmed. A preprint of this work is available under: https://biblio.ugent.be/publication/8515429

Performance improvement of existing three phase synchronous reluctance machine : stator upgrading to 5-phase with combined star-pentagon winding

This paper investigates the performance of 3-phase synchronous reluctance machines (SynRMs) when upgrading their stator to 5-phase, keeping the same rotor. The design of the 5-phase stator has been optimized to select the optimal dimensions of the slots and teeth. Moreover, a combined star-pentagon winding is employed to further improve the machine performance. Different winding configurations have been studied and compared using 2D Ansys Maxwell transient simulations. It is observed that at optimal current angle and rated current, the average torque is increased by 17.41% when changing the 3-phase stator with the proposed 5-phase one. In addition, the efficiency of the 5-phase SynRM is increased by about 0.8% compared to 3-phase SynRM. At 3 times the rated speed, the torque and efficiency are significantly increased by around 33% and 3.5% respectively. Moreover, the 5-phase SynRM shows a superior performance in the faulty case with one phase opened. It works at 98.84% of the rated torque of the healthy 3-phase machine, whereas the 3-phase machine works at only 43.35% with huge torque ripple (228%). Finally, an experimental validation using the reference 3-phase machine has been done

Refurbishing three‑phase synchronous reluctance machines to multiphase machines

Refurbishing electrical machines to have a higher performance and/or reliability is a clear trend in the circular economy. This paper investigates the gain in efficiency, torque density and reliability with replacing the windings and the iron of the stator of existing three-phase synchronous reluctance machines (SynRMs), resulting in a multiphase machine. The stator housing, shaft, bearings and the rotor are not changed, to keep the cost of refurbishing low. As the housing and rotor are kept, logical constraints are to have the same inner and/or outer stator diameters, air gap length and axial length. In the new windings, an identical copper volume is considered as a constraint. An optimization technique is coupled to 2D finite element method to select the optimal slot dimensions. Case studies showed that it is possible to replace the stator of existing three-phase SynRMs with a better performance multiphase one. It is found that the average torque, efficiency and power factor of the five-phase SynRM are increased by 11.78%, 0.72% and 5.54%, respectively, compared to a three-phase SynRM at rated conditions. At higher speeds (three times rated value), the efficiency and average torque are greatly improved by about 3.64% and 33.67%, respectively, compared to the three-phase SynRM. Moreover, a faulty case of one phase opened is also investigated. The five-phase SynRM works at 75.45% of the healthy rated torque of the three-phase SynRM, whereas the three-phase SynRM works at only 43%. Measurements on an existing 5.5-kW, three-phase SynRM confirm the observed results

Mathematical modelling, analysis and control of a three to five-phase matrix converter for minimal switching losses

The interest in motor drive systems with a number of phases greater than three has increased, mainly in high-power industrial fields due to their advantages compared with three-phase drive systems. In this paper, comprehensive mathematical modeling of a five-phase matrix converter (MC) is introduced. Besides that, the direct and indirect space vector modulation (SVM) control methods are compared and analyzed. Furthermore, a mathematical model for the MC with the transformation between the indirect and direct topology is constructed. The indirect technique is used to control the five-phase MC with minimum switching losses. In this technique, SVM deals with a five-phase MC as a virtual two-stage converter with a virtual DC link (i.e., rectifier and inverter stages). The voltage gain is limited to a value of 0.79. Moreover, to analyze the effectiveness of the control technique and the advantages of the MC, a static R-L load is employed. However, the load can also be an industrial load, such as hospital pumping or vehicular applications. The presented analysis proves that the MC gives a wide range of output frequencies, and it has the ability to control the input displacement factor and the output voltage magnitude. In addition, the absence of the massive DC link capacitors is an essential feature for the MC, resulting in increased reliability and a reduced size converter. Eventually, an experimental validation is conducted on a static load to validate the presented model and the control method. It is observed that good matching between the simulation and the experimental results is achieved

An Unusual Presentation of Jejunal Stenosis: A Case Report

Late presentation of jejunal atresia or stenosis is very rare. All patients present within the 1st to 5th day of life. They present with symptoms and signs of intestinal obstruction. Bilious vomiting is one of the most important and diagnostic feature. Other symptoms and signs of intestinal obstruction are very rare. In patients with duodenal stenosis the presentation is usually late and their main presenting symptom is failure to thrive with or without symptoms of intestinal obstruction. Here we present a thirty one month female who was seen with symptoms and signs of chronic intestinal obstruction. Her main symptoms were bilious vomiting, abdominal distension and constipation. The condition started since birth. Pregnancy was uneventful and she was an outcome of spontaneous vaginal delivery with birth weight of 3kg