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THE ROLE OF INNOVATION ACTIVITIES IN TOURISM AND REGIONAL GROWTH IN EUROPE
George M. Korres
Tourismos : an International Multidisciplinary Journal of Tourism , 2008,
Abstract: Tourism plays a crucial role for national economies throughout the world. In Europe, international tourism receipts were almost three times higher in the late 1990s than they were in the late 1980s. Tourism has great potential as regards contributing to the achievements of several major EU objectives, such as economic growth, employment, sustainable development and economic and social cohesion. The importance of innovation was long underestimated in service and tourism activities. Successful innovation, as for instance innovation that is also profitable to the tourism firm in a competitive market, must increase the value of the whole tourism product. The production and the dissemination of new technologies has been the subject of much research. This paper illustrates why technological innovation is considered as a major force in tourism industry. It also attempts to analyze the impact of technological innovation and the implications on regional growth of member states.
An Approach on Spatial Integration and Diffusion Process
George M. KORRES
Journal of Settlements and Spatial Planning , 2012,
Abstract: The importance of diffusion of technology for economic growth has been considerably emphasised in economic literature. This paper investigates the role and the impact of the diffusion of technology in economic contexts. It also attempts to analyze the diffusion models through epidemic and probit analysis models.
Optimal PMU Placement Using Nonlinear Programming
Nikolaos Theodorakatos,Nikolaos Manousakis,George Korres
Mathematics , 2015,
Abstract: Phasor Measurement Units (PMUs) are essential measuring devices for monitoring, control and protection of power systems. The objective of the optimal PMU placement (OPP) problem is to minimize the number of PMUs and select the bus locations to make a power system completely observable. In this paper, the OPP problem is formulated as a nonlinear programming (NLP) problem and a sequential quadratic programming (SQP) method is used for its solution. Simulations are carried out on IEEE standard test systems, using MATLAB. The numerical results are compared to those obtained by a binary integer programming (BIP) model, also implemented in MATLAB. The comparative study shows that the proposed formulation yields the same number of PMUs as the BIP model. The fundamental contribution of this paper lies in investigating the feasibility of using NLP for the solution of the OPP problem and the ability of the proposed methodology to provide multiple solutions in contrast to the binary integer programming model. The System Observability Redundancy Index is adopted to further rank the multiple solutions.
Excessive Paranasal Sinuses and Mastoid Aeration as a Possible Cause of Chronic Headache
Panagiotis Kousoulis,Jiannis Hajiioannou,Vassiliki Florou,Dimitrios Kretzas,George Korres
Case Reports in Otolaryngology , 2013, DOI: 10.1155/2013/836064
Abstract: The objective of this case report is to present a patient with chronic headache who was diagnosed with excessive aeration of all paranasal sinuses and mastoid air cells using computed tomography imaging. The volume and linear measurements of all of the cavities revealed values greater than the greatest values reported in the literature. To date, this is the second reported case of excessive enlargement of all paranasal sinuses and the first which includes the enlargement of the mastoid air cells. No surgical intervention was required for the patient, but in similar cases, with more severe symptoms, surgical treatment is a challenge for the surgeon and may mandate a multidisciplinary approach. 1. Introduction Excessive enlargement of the paranasal sinuses is a rare entity with an uncertain aetiology. In the medical literature, it has been described with many terms including hypersinus, pneumocele, pneumatocoele, sinus ectasia, hyperpneumatization, and pneumosinus dilatans. It usually affects the frontal sinus, although any sinus can be pathologically enlarged. We present a case of a patient with chronic headache, diagnosed with excessive aeration of all paranasal sinuses, together with atypical mastoid pneumatization. To the authors’ knowledge, this has not been previously reported in the literature. 2. Case Presentation A 38-year-old woman was referred for evaluation to the outpatient otorhinolaryngology clinic by the neurology department. The patient complained of intermittent episodes of moderate, nonthrobbing, and severe pressure-like headache since early adulthood. The headache was typically located at the anterior part of the cranium, mainly over the frontal, the anterior parietal, and temporal area. The symptoms usually lasted for hours and were sufficiently relieved by common analgesics such as paracetamol and nonsteroid anti-inflammatory drugs. The pain was not accompanied by facial swelling and was not related to head position (bending forward, lying down, or sitting up). Palpation of the face and anterior cranium did not reproduce the symptoms and no palpable or visually evident anatomic deformity was noted. Neurologic and ophthalmologic examinations were unremarkable. Routine laboratory parameters were within normal range. Nasal endoscopic examination did not reveal pathologic findings. The nasal septum was slightly deviated while the maxillary and sphenoid ostia appeared patent. Although the frontal sinus ostium could not be visualized endoscopically on either side, no mucosal abnormalities were apparent at the area of the frontal sinus
Diagnosis of Single- or Multiple-Canal Benign Paroxysmal Positional Vertigo according to the Type of Nystagmus
Dimitris G. Balatsouras,George Koukoutsis,Panayotis Ganelis,George S. Korres,Antonis Kaberos
International Journal of Otolaryngology , 2011, DOI: 10.1155/2011/483965
Abstract: Benign paroxysmal positional vertigo (BPPV) is a common peripheral vestibular disorder encountered in primary care and specialist otolaryngology and neurology clinics. It is associated with a characteristic paroxysmal positional nystagmus, which can be elicited with specific diagnostic positional maneuvers, such as the Dix-Hallpike test and the supine roll test. Current clinical research focused on diagnosing and treating various types of BPPV, according to the semicircular canal involved and according to the implicated pathogenetic mechanism. Cases of multiple-canal BPPV have been specifically investigated because until recently these were resistant to treatment with standard canalith repositioning procedures. Probably, the most significant factor in diagnosis of the type of BPPV is observation of the provoked nystagmus, during the diagnostic positional maneuvers. We describe in detail the various types of nystagmus, according to the canals involved, which are the keypoint to accurate diagnosis.
Study of Allergic Rhinitis in Childhood
Dimitrios G. Balatsouras,George Koukoutsis,Panayotis Ganelis,Alexandros Fassolis,George S. Korres,Antonis Kaberos
International Journal of Otolaryngology , 2011, DOI: 10.1155/2011/487532
Abstract: Allergic rhinitis is common among children and quite often represents a stage of the atopic march. Although sensitization to food and airborne allergens may appear in infancy and early childhood, symptoms of the disease are usually present after age 3. The aim of this study was to determine the most frequent food and indoor and outdoor respiratory allergens involved in allergic rhinitis in children in the region of Piraeus. The study was performed in the outpatient clinic of otolaryngologic allergy of a general hospital. Fifty children (ranged 6–14 ) with symptoms of allergic rhinitis and positive radioallergosorbent test (RAST) for IgE antibodies or skin prick tests were included in the study. Thirty six (72%) of the subjects of the study had intermittent allergic rhinitis. The most common aeroallergens determined were grass pollens and Parietaria, whereas egg and milk were the food allergens identified. The detection of indoor and outdoor allergens in the region of Piraeus, based on skin prick tests and RAST tests, showed high incidence of grasses and food allergens, which is similar to other Mediterranean countries.
Transiently Evoked Otoacoustic Emissions in Children with Otitis Media with Effusion
Dimitris G. Balatsouras,George Koukoutsis,Panayotis Ganelis,George S. Korres,Andreas Aspris,Antonis Kaberos
International Journal of Otolaryngology , 2012, DOI: 10.1155/2012/269203
Abstract: Introduction. Otitis media with effusion is a common pediatric disease whose diagnosis is based on pneumatic otoscopy, pure-tone audiometry, and tympanometry. The aim of this study was to evaluate transiently evoked otoacoustic emissions in the diagnosis of otitis media with effusion as compared to tympanometry. Patients and Methods. 38 children with bilateral otitis media with effusion were studied. 40 normal children of similar age and sex were used as controls. All subjects underwent pneumatic otoscopy, standard pure-tone audiometry, tympanometry, and transiently evoked otoacoustic emissions. Results. In the group of children with bilateral otitis media, transiently evoked otoacoustic emissions were absent in 51 ears (67%). In the remaining 25 ears (33%) the mean emission amplitude was reduced, as compared to the mean value of the control group. Conclusions. Transiently evoked otoacoustic emissions should be included in the diagnostic workup of otitis media with effusion because it is a fast, reliable, and objective test. Transiently evoked otoacoustic emissions should always be used in conjunction with tympanometry, because a more meaningful interpretation of transiently evoked otoacoustic emissions measures is possible.
Transiently Evoked Otoacoustic Emissions in Children with Otitis Media with Effusion
Dimitris G. Balatsouras,George Koukoutsis,Panayotis Ganelis,George S. Korres,Andreas Aspris,Antonis Kaberos
International Journal of Otolaryngology , 2012, DOI: 10.1155/2012/269203
Abstract: Introduction. Otitis media with effusion is a common pediatric disease whose diagnosis is based on pneumatic otoscopy, pure-tone audiometry, and tympanometry. The aim of this study was to evaluate transiently evoked otoacoustic emissions in the diagnosis of otitis media with effusion as compared to tympanometry. Patients and Methods. 38 children with bilateral otitis media with effusion were studied. 40 normal children of similar age and sex were used as controls. All subjects underwent pneumatic otoscopy, standard pure-tone audiometry, tympanometry, and transiently evoked otoacoustic emissions. Results. In the group of children with bilateral otitis media, transiently evoked otoacoustic emissions were absent in 51 ears (67%). In the remaining 25 ears (33%) the mean emission amplitude was reduced, as compared to the mean value of the control group. Conclusions. Transiently evoked otoacoustic emissions should be included in the diagnostic workup of otitis media with effusion because it is a fast, reliable, and objective test. Transiently evoked otoacoustic emissions should always be used in conjunction with tympanometry, because a more meaningful interpretation of transiently evoked otoacoustic emissions measures is possible. 1. Introduction Otitis media with effusion is a common pediatric disease and is considered the most common cause of hearing impairment among children [1]. Diagnosis is mainly based on pneumatic otoscopy, pure-tone audiometry, and tympanometry. Tympanometry is an objective technique that can detect abnormal middle-ear function consistent with the presence of fluid in the middle-ear cavity [2]. Transiently evoked otoacoustic emissions (TEOAEs) are a diagnostic method widely used during the past decade to study cochlear function, in a noninvasive and objective manner. Usually, TEOAEs are present in people who have normal cochlear function and a healthy middle ear [3]. Although extensive experience from the use of TEOAEs in widespread neonatal hearing screening has been gained [4], little data has been gathered from the population of preschool and school-aged children. Because otoacoustic emissions are transmitted from the cochlea to the external ear canal via the middle ear, the transmission properties of the middle ear directly influence their characteristics. In general, middle-ear effusion reduces measured emission amplitudes and sometimes eliminates the response entirely [5]. The aim of this study was to evaluate TEOAEs in the diagnosis of otitis media with effusion in comparison with tympanometry. 2. Material and Methods A group
Diagnosis of Single- or Multiple-Canal Benign Paroxysmal Positional Vertigo according to the Type of Nystagmus
Dimitris G. Balatsouras,George Koukoutsis,Panayotis Ganelis,George S. Korres,Antonis Kaberos
International Journal of Otolaryngology , 2011, DOI: 10.1155/2011/483965
Abstract: Benign paroxysmal positional vertigo (BPPV) is a common peripheral vestibular disorder encountered in primary care and specialist otolaryngology and neurology clinics. It is associated with a characteristic paroxysmal positional nystagmus, which can be elicited with specific diagnostic positional maneuvers, such as the Dix-Hallpike test and the supine roll test. Current clinical research focused on diagnosing and treating various types of BPPV, according to the semicircular canal involved and according to the implicated pathogenetic mechanism. Cases of multiple-canal BPPV have been specifically investigated because until recently these were resistant to treatment with standard canalith repositioning procedures. Probably, the most significant factor in diagnosis of the type of BPPV is observation of the provoked nystagmus, during the diagnostic positional maneuvers. We describe in detail the various types of nystagmus, according to the canals involved, which are the keypoint to accurate diagnosis. 1. Introduction Of all the inner ear disorders that can cause dizziness or vertigo, benign paroxysmal positional vertigo (BPPV) is by far the most common [1]. Additionally, it is a condition that in most instances may be easily diagnosed and treated, with a simple office-based procedure [2]. Since the initial description by Bárány in 1921 [3], there have been major advances in the understanding of this common condition. Recently, modern clinical research focused on diagnosing and treating various types of BPPV, according to the semicircular canal involved and according to the implicated pathogenetic mechanism. Multiple-canal BPPV has been specifically investigated, as the main source of various atypical forms of the disease, which until now were resistant to treatment with standard canalith repositioning procedures (CRPs) [4, 5]. The purpose of this paper is to present the data regarding the various types of nystagmus produced during the diagnostic maneuvers of BPPV, which in conjunction with the patient’s history and symptoms, will help in obtaining accurate diagnosis and appropriate treatment. In all subsequent discussions, the various types of nystagmus will be described according to their fast phase, relative to the patient’s perspective (e.g., as horizontal nystagmus with a fast phase beating towards the patient's right ear is termed rightward horizontal nystagmus and a rightward torsional nystagmus, which is beating towards the patient's right ear, is a counterclockwise nystagmus, as seen by the observer). 2. Unilateral Posterior Canal BPPV This is the
Study of Allergic Rhinitis in Childhood
Dimitrios G. Balatsouras,George Koukoutsis,Panayotis Ganelis,Alexandros Fassolis,George S. Korres,Antonis Kaberos
International Journal of Otolaryngology , 2011, DOI: 10.1155/2011/487532
Abstract: Allergic rhinitis is common among children and quite often represents a stage of the atopic march. Although sensitization to food and airborne allergens may appear in infancy and early childhood, symptoms of the disease are usually present after age 3. The aim of this study was to determine the most frequent food and indoor and outdoor respiratory allergens involved in allergic rhinitis in children in the region of Piraeus. The study was performed in the outpatient clinic of otolaryngologic allergy of a general hospital. Fifty children (ranged 6–14?) with symptoms of allergic rhinitis and positive radioallergosorbent test (RAST) for IgE antibodies or skin prick tests were included in the study. Thirty six (72%) of the subjects of the study had intermittent allergic rhinitis. The most common aeroallergens determined were grass pollens and Parietaria, whereas egg and milk were the food allergens identified. The detection of indoor and outdoor allergens in the region of Piraeus, based on skin prick tests and RAST tests, showed high incidence of grasses and food allergens, which is similar to other Mediterranean countries. 1. Introduction Allergic rhinitis is one of the most common disorders, which affects 5–40% of population, according to various reports [1, 2]. It may be classified as persistent and intermittent allergic rhinitis, depending on the frequency of symptoms. It presents a high morbidity because it affects social life, professional activities, and, especially in children, school performance [3]. Allergic rhinitis is common among children and quite often represents a stage of the atopic march [4]. Although sensitization to food and airborne allergens may appear in infancy and early childhood, symptoms of the disease are usually present after age 3. The aim of this study was to determine the most frequent respiratory and food allergens as a cause of allergic rhinitis in children in the region of Piraeus. 2. Materials and Methods We examined 50 children who presented with allergic rhinitis in the outpatient clinic of otolaryngologic allergy, belonging to the ENT department of our hospital. The age of the patients ranged from 6 to 14 years (mean 10.7 ± 2.1), and they were all living in the region of Piraeus. Diagnosis was on the basis of a history of allergic rhinitis, either seasonal or perennial, on the findings of clinical examination and on the presence of positive radioallergosorbent (RAST) test for IgE antibodies (RAST-CAP-FEIA, Pharmacia, Uppsala, Sweden). All children were tested in a series of allergens, including grasses, cereales,
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