Fixed points on band structures of non-Hermitian models and the resulting extended states in the bandgap and ideal superluminal tunneling

PT symmetry in non-Hermitian electronic models has drawn much attention over the past decade mainly because it guarantees that the band structures calculated under open boundary conditions be the same as those calculated under periodic boundary conditions. PT symmetry in electromagnetic (EM) models, which are usually borrowed from electronic models, has also been of immense interest mainly because it leads to 'exceptional' parameter values below which non-Hermitian operators have real eigenvalues, although PT symmetry is not the sole symmetry which allows such exceptional parameter values. In this article, we examine 1-dimensional PT-symmetric non-Hermitian EM models to introduce novel concepts and phenomena. We introduce the band-structure concept of 'fixed points', which leads to 'bidirectional' reflection zeros in the corresponding finite structures, contrary to a common belief about the EM structures with PT symmetry (and without P and T symmetries). Some of the fixed points manifest themselves as what we name 'extended states in the bandgap' on the band structure while some other fixed points are the 'turning points' of the band structure. The extended states in the band gap are in fact the dual of the well-known 'bound stated in the continuum' while the turning points allow us to observe 'ideal' superluminal tunneling in the corresponding finite structures. By 'ideal' superluminal tunneling we mean the case where not only the transmission coefficient has an almost uniform phase over a broad bandwidth but also the magnitudes of the transmission and reflection coefficients are almost equal to unity and zero, respectively, over the bandwidth

The feasibility and benefits of using high-strength concrete for construction purposes in earthquake prone areas

In recent years, concrete technology has benefited from great advances and evolutions that lead to emergence of new concrete with different properties. One of the most important of these concretes is high strength concrete (HSC). The emergence of HSC has made possible to high-rise buildings and towers with architectural art and delicacy and it is expected that in the next few years, there is the possibility of using HSC in wider areas. Examining the studies on this type of concrete, this paper has deal with the feasibility and benefits of using HSC for construction purposes in earthquake prone areas. The results of this study show that in case of respecting the bylaw constrains and conformity of new bylaws with this type of concrete, it is hoped to use it as a reliable option for safe construction in seismic areas.Keywords: Concrete, High-Strength, Construction, Seismic Area, Feasiblit

Incidence of Snake Bites in Kashan, Iran During an Eight Year Period (2004-2011)

Background: Snake bites are one of the significant health problems in the tropical and subtropical regions. Snake bite is a common medical emergency in Iran, and the epidemiological features and management of such cases vary from region to region. Objectives: This present research study was conducted to obtain new information about the epidemiology of snake bites in the region of Kashan, located in the central part of Iran. Patients and Methods: This research was a descriptive retrospective study. Data from 2004 to 2011 of snakebite cases were collected from case reports. Information included; age and sex of the victim, district, month of incident, mortality, and time of bite. Results: The results of this study showed that the majority of snake bite patients were male (96%). The age distribution of patients indicated that the greatest rate of snake bites occurred among the 15-24 year old group. Data collected in this study revealed that the highest incidence of snake bite cases took place in summer (60%) and the lowest number occurred in winter, with no snake bite cases being recorded. The peak number of snakebite cases was seen during June-September. Conclusions: It was concluded that snake bite cases in Kashan are similar to other areas in Iran from an epidemiological point of view, including; age distribution rates, gender and site of the bites. The existence of Macrov ipera lebetina, a dangerous venomous snake, can cause a range of clinical effects among residents in central parts of Iran, such as Kashan area

Chest Injury Evaluation and Management in Two Major Trauma Centers of Isfahan Province, IR Iran

Background:: Chest trauma is responsible for 50% of deaths due to trauma. This kind of death usually occurs immediately after the trauma has occurred. Objectives:: The aim of this study was to evaluate the various aspects of chest trauma in patients admitted to two main trauma centers located in the Isfahan Province, Iran. Patients and Methods:: During a six month period, a cross-sectional study of 100 patients who had sustained a chest injury was carried out. Data, including; age, sex, time of accident, trauma mechanism, organ injury, hospitalization length, complications, and patient outcomes were recorded and analyzed. Results:: The mean ages of the patients were 24.7 ± 3.1 years. Men were injured four times more often than the women. Blunt trauma was the most common type of injury. The incidence of hemothorax was 38% in blunt traumas, and 45% (P = 0.01) in penetrating ones. The incidence of pneumothorax was 43% in blunt traumas and 20% in penetrating ones (P = 0.03). The length of hospitalization was 7.2 ± 3.2 days for blunt and 10.1 ± 3.1 days for penetrating chest traumas. Five patients (5%) died during hospitalization, three of those deaths were due to arterial injuries and two cases were due to lung contusions. Conclusions:: Since hemothorax is the main complication of blunt chest trauma in young men, we recommend that special consideration needs to be made to any case of chest trauma, especially blunt chest injuries

Omental Torsion After Repeated Abdominal Blunt Trauma

Omental torsion is caused by the rotation of the greater omentum on its axis which may lead to tissue infarction and necrosis. It is a rare cause of acute abdomen. Signs, symptoms and paraclinical data are not specific. The patients usually undergo laparotomy for acute abdomen of poorly defined origin. High index of suspicious is required for the diagnosis of this entity. The diagnosis is usually confirmed after an explorative laparotomy. We present clinical characteristics and imaging findings of omental torsion in a young man following repeated blunt abdominal trauma

Institutional analysis of management accounting change in local government: Through three, institutional levels in Middle East case study,

This paper examines why and how Abu Dhabi Police, have seen a succession of changes in various aspects of their management control. These management changes relate to such aspects of their strategic plan, balanced scorecard (BSC), European Foundation for Quality Management (EFQM), Key Performance Indicators (KPIs), zero based budget and organizational structure. All these reforms regarded as to the introduction of New Public Management (NPM). The focus lies in new institutional sociology (NIS), particularly the institutional change framework of Dillard et al. (2004): the economic and political level, organizational field level and organizational level. The Dillard’s framework accommodated many features of institutionalization but needed extension to incorporate the role of critical factors that influence the successful introduction and implementation of management accounting change in public sector organizations. The results based on the qualitative methodology confirm the impact of the critical factors at each level and the effects of those factors on the performance, management and accounting change within Abu Dhabi Police organization. However, why Abu Dhabi Police, adopted NPM lay in a complex, interrelated chain of institutions, including Abu Dhabi City government, change agency (internal and external consultants) and the United Arab Emirates (UAE) vision, mission and objectives