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Background Vitiligo is acquired depigmentary disorder characterized by destruction of the epidermal melanocytes leading to the loss of the skin color. Oxidative stress has a major role in the aetiopathogenesis and in melanocytic destruction due to its accumulation in the melanocytes and the hazardous effects to all compartments of the cell. Objective The aim of the work was to evaluate the level of E-cadherin and H2O2 level in vitiligo versus controls. Subjects This is a case control study which was carried out at Department of Dermatology, Venereology and Andrology,New Cairo Police Academy Hospital on 20 Subjects were divided into two groups, Group I included 10 patients having non segemental vitiligo. Group II included 10 non vitilignous controls were included in the study. Results We found that H2O2 level is increased in NSV patients when compared with healthy individuals. While E-cadherin level is significantly decreased in vitiligo skin compared to normal skin. Conclusion As compared to controls, increased H2O2 levels levels were suggestive of oxidative stress in patients of vitiligo in our study. From our results we can conclude that vitiligo is not a disease confined to melanocytes only, keratinocytes also showed certain pathological changes in vitiliginous lesions. As functional and structural units with melanocytes, keratinocytes in depigmented epidermis may constitute a different microenvironment compared to those in normally pigmented epidermis. These differences include obvious loss of cell to cell adhesion between keratinocytes and melanocytes and between keratinocytes and each other, which in turn may affect the pigmentary system of the skin.

The rapid growth of wireless industry opens the door to several use cases such as internet of things and device-to-device communications, which require boosting the reliability and the spectral efficiency of the wireless access network, while reducing the energy consumption at the terminals. The vast spectrum available in millimeter-wave (mmWave) frequency band is one of the most promising candidates to achieve high-speed communications. However, the propagation of the radio signals at high carrier frequencies suffers from severe path-loss which reduces the coverage area. Fortunately, the small wavelengths of the mmWave signals allow packing a large number of antennas not only at the base station (BS) but also at the user terminal (UT). These massive antenna arrays can be exploited to attain high beamforming and combining gains and overcome the path-loss associated with the mmWave propagation. In conventional (fully digital) multiple-input-multiple-output (MIMO) transceivers, each antenna is connected to a specific radio-frequency (RF) chain and high resolution analog-to-digital-converter. Unfortunately, these devices are expensive and power hungry especially at mmWave frequency band and when operating in large bandwidths. Having this in mind, several MIMO transceiver architectures have been proposed with the purpose of reducing the hardware cost and the energy consumption. Fully connected hybrid analog and digital precoding schemes were proposed in with the aim of replacing some of the conventional RF chains by energy efficient analog devices. These fully connected mapping requires many analog devices that leads to non-negligible energy consumption. Partially connected hybrid architectures have been proposed to improve the energy efficiency of the fully connected transceivers by reducing the number of analog devices. Simplifying the transceiver’s architecture to reduce the power consumption results in a degradation of the attained spectral efficiency. In this PhD dissertation, we propose novel modulation schemes and massive MIMO transceiver design to combat the challenges at the mmWave cellular systems. The structure of the doctoral manuscript can be expressed as In Chapter 1, we introduce the transceiver design challenges at mmWave cellular communications. Then, we illustrate several state of the art architectures and highlight their limitations. After that, we propose scheme that attains high-energy efficiency and spectrum efficiency. In chapter 2, first, we mathematically describe the state of the art of the SM and highlight the main challenges with these schemes when applied at mmWave frequency band. In order to combat these challenges (for example, high cost and high power consumption), we propose novel SM schemes specifically designed for mmWave massive MIMO systems. After that, we explain how these schemes can be exploited in attaining energy efficient UT architecture. Finally, we present the channel model, systems assumptions and the transceiver devices power consumption models. In chapter 3, we consider single user SM system. First, we propose downlink (DL) receive SM (RSM) scheme where the UT can be implemented with single or multiple radio-frequency chains and the BS can be fully digital or hybrid architecture. Moreover, we consider different precoders at the BS and propose low complexity and efficient antenna selection schemes for narrowband and wideband transmissions. After that, we propose joint uplink-downlink SM scheme where we consider RSM in the DL and transmit SM (TSM) in the UL based on energy efficient hybrid UT architecture. In chapter 4, we extend the SM system to the multi-user case. Specifically, we develop joint multi-user power allocation, user selection and antenna selection algorithms for the broadcast and the multiple access channels. Chapter 5 is presented for concluding the thesis and proposing future research directions. Considerando los altos requerimientos de los servicios de nueva generación, las infraestructuras de red actual se han visto obligadas a evolucionar en la forma de manejar los diferentes recursos de red y computación. Con este fin, nuevas tecnologías han surgido para soportar las funcionalidades necesarias para esta evolución, significando también un gran cambio de paradigma en el diseño de arquitecturas para la futura implementación de redes.En este sentido, este documento de tesis doctoral presenta un análisis sobre estas tecnologías, enfocado en el caso de redes inter/intra Data Centre. Por consiguiente, la introducción de tecnologías basadas en redes ópticas ha sido estudiada, con el fin de identificar problemas actuales que puedan llegar a ser solucionados mediante el diseño y aplicación de nuevas técnicas, asimismo como a través del desarrollo o la extensión de los componentes de arquitectura de red.Con este propósito, se han definido una serie de propuestas relacionadas con aspectos cruciales, así como el control de dispositivos ópticos por SDN para habilitar el manejo de redes híbridas, la necesidad de definir un mecanismo de descubrimiento de topologías ópticas capaz de exponer información precisa, y el analizar las brechas existentes para la definición de una arquitectura común en fin de soportar las comunicaciones 5G.Para validar estas propuestas, se han presentado una serie de validaciones experimentales por medio de escenarios de prueba específicos, demostrando los avances en control, orquestación, virtualización y manejo de recursos con el fin de optimizar su utilización. Los resultados expuestos, además de corroborar la correcta operación de los métodos y componentes propuestos, abre el camino hacia nuevas formas de adaptar los actuales despliegues de red respecto a los desafíos definidos en el inicio de una nueva era de las telecomunicaciones.

Hashim M Hussein, Ahmed S Raafat, Zainab S Amory, Mohammed Jasim AL-JubooriDepartment of Dentistry, Al-Rafidain University-College, Baghdad, IraqBackground: During endodontic treatment, endodontists must be aware of the various factors that may decrease or increase blood pressure. This study aimed to assess the mean percentages of systolic, diastolic, and arterial blood pressure (MSBP, MDAP, MABP) reduction in patients with vital irreversible pulpitis in teeth and who were treated at three visits to endodontists in three age groups (20–34years, 35–50years, 51–65years).Materials and methods: A total of 100 teeth with vital irreversible pulpitis from 100 patients were included. All patients underwent 3 visits for endodontic treatment. The 1st visit included removal of vital pulp tissue and a determination of working length, the 2nd visit included canal preparation and widening, and at the 3rd visit the canal was obturated and sealed by gutta percha and sealer. Blood pressure for all patients was checked and documented once before starting treatment and three times during treatment at different intervals during all visits.Results: There were significantly higher percentage reductions in MSBP, MDBP, and MABP at the 1st visit for endodontic treatment in comparison to other visits (2nd and 3rd) for all patients. Additionally, there were significantly higher percentage reductions in MSBP, MDBP, and MABP at the 1st visit for endodontic treatment in comparison to other visits in males and females, for all age groups, both anesthesia injection-type groups (infiltration and block), and all treated tooth types except mandibular anterior teeth, and there were nonsignificant differences among groups. However, there were nonsignificant differences in MSBP, MDBP, and MABP between males and females, between infiltration and block injection groups and in relation to teeth types at all visits.Conclusions: The reduction of blood pressure in patients undergoing endodontic treatment of vital teeth with irreversible pulpits is common, especially at the 1st visit for pulp extirpation.Keywords: irreversible pulpitis, endodontic treatment, vital teeth, anesthesia, age, gender

Heterotopic ossification (HO) is the presence of bone in nonossifying tissue. Mesenteric HO usually results from previous abdominal trauma or surgery. This is a case report of 87-year-old lady who presented with subacute intestinal obstruction, she had neither previous history of abdominal trauma nor surgery. On exploration, there was spiral ossified tissue trapping small bowel that was removed and the condition resolved completely. As long as to our knowledge, this is the first reported case of intra-abdominal Heterotopic ossification without previous cause in English articles. HO should keep in mind in any ossified peritoneal lesion even without previous surgery or trauma.

Introduction: Colostomy closure is an operation frequently performed in surgical practice, despite its benefits, it can produce significant morbidity and mortality. We have focused on the complications related to this surgery in regard to the closure technique and the optimal time for stoma closure and on the proper wound management in the postoperative period. Patients and Methods: Ninety-six patients were male between 17 and 53 years (median 35), they have been subjected to colostomy closure surgery in single-layer (52 cases) and double-layer (44 cases) closure techniques according to the surgeon preference. The interval time for colostomy closure was more than 3 months in 56 cases, while the interval time was Results: The total number of complications was 26 (27.08%), as fecal fistula 10 cases and wound infection 16 cases. Colostomy closure more than 3 months interval had 12.5% postoperative complications versus 47.5% if Discussion: The incidence of complications was more in double-layer (continuous) technique of closure colostomy versus single layer. While if the interval time for stoma closure is 3 months and more, it would give good results. Regarding wound management, delayed primary wound closure resulted in a better wound healing than the conventional skin closure technique. Conclusion: Based on this experience, we believe that colostomy closure can be performed with minimal morbidity and would result in a successful surgical outcome. Providing a meticulous technique used by a single layer (continuous seromuscular sutures plus stay sutures) anastomosis, more than three months interval time and a delayed wound closure the outcome will be much better.

Background: It is still a point of controversy if performing delayed primary closure (DPC) of abdominal incisions in cases of abdominal septic operations could be able to reduce incidence of surgical-site infection and its bad long term sequels in comparison with immediate primary closure (PC). The Aim: To compare between delayed primary closure and immediate primary closure of abdominal incisions, in patients with peritonitis that results from septic operations regarding superficial surgical site infection. Patients & Methods: we have carried out such study on 60 patients with septic peritonitis that were collected and operated surgically during 2 years in in Department of General Surgery, Zagazig University Hospital. We have divided our cases into 2 groups; Group (1): cases that are managed by immediate PC of the skin and subcutaneous tissue using polypropylene sutures and insertion of subcutaneous drain. Group (2): included cases that are managed by DPC of the skin and subcutaneous tissue, using polypropylene sutures and without insertion of drain. We have followed all patients for 2 weeks for; infection or dehiscence of the wound and for occurrence of burst abdomen, seroma or sub cutaneous collection. Results: we have detected that DPC is better than immediate PC as regard decreasing incidence of wound infection & dehiscence (p=0,009), less liability for occurrence of burst abdomen (p=0.042), sub cutaneous collection (p=0.003) and seroma (p