Wave transformation from statistically rough surface

The generalized small perturbation method is applied to investigate the transformation of waves on statistically rough surface separating media in which several types of waves caused by a time and spatial dispersion propagate. The field boundary conditions have been formulated. The mean intensity of the transformed fields have been calculatedОбобщенный метод малых возмущений использован для исследования трансформации волн на статистически шероховатой поверхности, разделяющей среды, в которых изза наличия временной и пространственной дисперсий распространяются несколько типов волн. Сформулированы для поля граничные условия. Рассчитана средняя интенсивность трансформированных волн.Узагальнений метод малих збурень використано для дослідження трансформації хвиль на статистично шорсткій поверхні, що розділяє середовища, в яких із-за наявності часової та просторової дисперсій розповсюджуються декілька типів хвиль. Сформульовано для поля граничні умови. Розраховано середню інтенсивність трансформованих хвиль

ALLERGIC CONTACT DERMATITIS WITH AN UNUSUAL CONFIGURATION AFTER PREOPERATIVE POVIDONE-IODINE DISINFECTION. A CLINICAL CASE

Contact dermatitis is an inflammatory skin reaction resulting from skin contact with exogenous substances that act as allergens and/or irritants. Epicutaneous testing is the gold standard for diagnosing allergic contact dermatitis and differentiating it from irritant contact dermatitis. We present a clinical case of allergic contact dermatitis after preoperative povidone-iodine disinfection

Influence of atmospheric circulation on the spatial distribution of precipitation in the area of Sofia city

The study aims to reveal spatial distribution of precipitation in the area of Sofia city during the decade 2013 - 2022 and the influence of atmospheric circulation. Statistical methods and cartographic approach are the main tools in this research. The spatial distribution of precipitation is characterized by low amounts (560 mm) in the northern and northeastern parts of Sofia depression and high amounts (760 mm) in the southern part. The main factor for this spatial distribution of precipitation is atmospheric circulation. The relief has a significant modifying effect and affects precipitation through several mechanisms. The most important is the location of mountain slope relative to the main direction of transport of air masses. Leeward slopes receive less precipitation and windward slopes receive more. The second mechanism of influence is anthropogenic relief (high buildings), which is a positive relief form compared to the surrounding plane having respective windward and leeward slopes. This study revealed a third mechanism of relief influence on spatial distribution of precipitation. The large difference in the height of the mountains located south of Sofia creates a significant difference in the air temperature in Sofia depression during a transport of air masses from south and southwest. This is due to the stronger foehn effect of the higher mountain (Vitosha) compared to the foehn effect of the lower mountains (Lyulin, Lozenska Planina), which creates a tongue of higher air temperature northeast of Vitosha, which reaches the southern and southwestern slopes of Stara Planina. The higher temperatures in this tongue create stronger upward air movements, which in turn increase the amount of precipitation. Secondary, but still important factors that affect the spatial distribution of precipitation in Sofia region are the urban heat island and the increased content of aerosols in the air in and over the city

Dynamical Instabilities and Deterministic Chaos in Ballistic Electron Motion in Semiconductor Superlattices

We consider the motion of ballistic electrons within a superlattice miniband under the influence of an alternating electric field. We show that the interaction of electrons with the self-consistent electromagnetic field generated by the electron current may lead to the transition from regular to chaotic dynamics. We estimate the conditions for the experimental observation of this deterministic chaos and discuss the similarities of the superlattice system with the other condensed matter and quantum optical systems.Comment: 6 pages, RevTEX; 4 fig

Marinas may act as hubs for the spread of the pseudo-indigenous bryozoan <em>Amathia verticillata</em> (Delle Chiaje, 1822) and its associates

The spaghetti bryozoan Amathia verticillata, formerly known as Zoobotryon verticillatum, was first described in 1822 from Naples, Italy, although this species was already present in 1807 at Cadiz, Spain. This ctenostome has long been considered a native species in the Mediterranean Sea but it has recently been suggested to be of Caribbean origin. It is most likely to have been introduced by vessels as hull fouling. This pseudo-indigenous species, i.e. a non-indigenous species (NIS) having been perceived to be native, has been found in several marinas and harbours within the Mediterranean Sea. In November 2014, this bryozoan species was abundant in the La Grande Motte marina on the south coast of France. Several thousand colonies were estimated to be present within this marina attached to the floating pontoon units that supported a floating boardwalk. Of the berthed craft examined, 31% were fouled with this species, and it was occasionally a prominent fouling species. Several macroinvertebrate species were associated with A. verticillata colonies, including some NIS, Paracerceis sculpta, Paranthura japonica and Caprella scaura, that are recorded for the first time from the Mediterranean coast of France. A. verticillata might support their transfer elsewhere by providing a habitat and substrate when attached to vessel hulls

Dissipative Chaos in Semiconductor Superlattices

We consider the motion of ballistic electrons in a miniband of a semiconductor superlattice (SSL) under the influence of an external, time-periodic electric field. We use the semi-classical balance-equation approach which incorporates elastic and inelastic scattering (as dissipation) and the self-consistent field generated by the electron motion. The coupling of electrons in the miniband to the self-consistent field produces a cooperative nonlinear oscillatory mode which, when interacting with the oscillatory external field and the intrinsic Bloch-type oscillatory mode, can lead to complicated dynamics, including dissipative chaos. For a range of values of the dissipation parameters we determine the regions in the amplitude-frequency plane of the external field in which chaos can occur. Our results suggest that for terahertz external fields of the amplitudes achieved by present-day free electron lasers, chaos may be observable in SSLs. We clarify the nature of this novel nonlinear dynamics in the superlattice-external field system by exploring analogies to the Dicke model of an ensemble of two-level atoms coupled with a resonant cavity field and to Josephson junctions.Comment: 33 pages, 8 figure

Coralline Algae in a Changing Mediterranean Sea: How Can We Predict Their Future, if We Do Not Know Their Present?

In this review we assess the state of knowledge for the coralline algae of the Mediterranean Sea, a group of calcareous seaweeds imperfectly known and considered highly vulnerable to long-term climate change. Corallines have occurred in the Mediterranean area for ∼140 My and are well-represented in the subsequent fossil record; for some species currently common the fossil documentation dates back to the Oligocene, with a major role in the sedimentary record of some areas. Some Mediterranean corallines are key ecosystem engineers that produce or consolidate biogenic habitats (e.g., coralligenous concretions, Lithophyllum byssoides rims, rims of articulated corallines, maerl/rhodolith beds). Although bioconstructions built by corallines exist virtually in every sea, in the Mediterranean they reach a particularly high spatial and bathymetric extent (coralligenous concretions alone are estimated to exceed 2,700 km2 in surface). Overall, composition, dynamics and responses to human disturbances of coralline-dominated communities have been well-studied; except for a few species, however, the biology of Mediterranean corallines is poorly known. In terms of diversity, 60 species of corallines are currently reported from the Mediterranean. This number, however, is based on morphological assessments and recent studies incorporating molecular data suggest that the correct estimate is probably much higher. The responses of Mediterranean corallines to climate change have been the subject of several recent studies that documented their tolerance/sensitivity to elevated temperatures and pCO2. These investigations have focused on a few species and should be extended to a wider taxonomic set

THE CATEGORIES OF GOOD AND BAD IN MODERN BULGARIAN BASED ON THE NOTIONS OF ORDER, ORDERLINESS AND DISORDER, HAHOS

The paper deals with the concepts of GOOD and BAD as reflected in the Bulgarian lexical system within the framework of the Cognitive Metaphor Theory, developed by Lakoff and Johnson. The study claims that the concepts of GOOD and BAD are undoubtedly grounded in human experience but are conceptualized by means of metaphors as such concepts do not exist objectively in the physical world but result from human understanding of it. The cognitive metaphors discussed in the paper are studied with reference to human understanding of order, orderliness and disorder, chaos in the world.Kategorie DOBRA i ZŁA w języku bułgarskim na podstawie wyobrażeń o ŁADZIE i PORZĄDKU oraz NIEPORZĄDKU i CHAOSIEW artykule poddano analizie koncepty DOBRA i ZŁA, odzwierciedlone w systemie leksykalnym języka bułgarskiego, z perspektywy kognitywnej teorii metafory G. Lakoffa i M. Johnsona. Badanie opiera się na założeniu, że koncepty DOBRO i ZŁO należą niewątpliwie do bezpośredniego doświadczenia ludzkiego, ale mimo to podlegają metaforyzacji dzięki faktowi, że nie istnieją obiektywnie, lecz są wynikiem ludzkiego rozumienia świata. Analiza zebranego materiału prowadzi do wniosku, że przedstawione w opracowaniu kognitywne metafory bazują na pojęciach ładu i porządku oraz nieporządku i chaosu w świecie.The paper deals with the concepts of good and bad as reflected in the Bulgarian lexical system within the framework of the Cognitive Metaphor Theory, developed by G. Lakoff and M. Johnson. The study claims that the concepts of good and bad are undoubtedly grounded in human experience but are conceptualized by means of metaphors as such concepts do not exist objectively in the physical world but result from human understanding of it. The cognitive metaphors, discussed in the paper, are studied with reference to human understanding of order, orderliness and disorder, chaos in the world

Research on Allergic Dermatitis in the Varna Region // Проучване върху алергодерматозите във Варненски регион

In different age groups, there is a difference in contact hypersensitivity to individual allergens: in the age group 0-20 years - the most common allergen is methylisothialisinone - 36,36 %; in the age group 21-40 years - the most common allergen is nickel - 30 %; in the age group 41-60 years - the most common allergens are cobalt and textile dyes - 24 %; in the age group 61-80 years - the most common allergens are potassium dichromate, nickel, cobalt and Peruvian balm – 16,67 %. The most common location is on the upper limbs - 35%, followed by the face - 29%, palms - 28%, lower limbs - 25%, back - 23%, chest - 19%, neck - 13 %, scalp - 9%, feet - 6%. Rarely (1%) skin changes are localized in the nail area, axillary, in the area of the gluteus and on the genitals. We found a statistically significant relationship between patients' gender and facial area. A statistically significant association was found in upper limb involvement and hypersensitivity to potassium dichromate and rosin; when affecting the palms and hypersensitivity to nickel, lower limb involvement and hypersensitivity to methylisothiazolinone, as well as in the case of neck and contact hypersensitivity to perfume mix I. While comparing the results for contact sensitization in patients from the Varna region (2018 - 2020) with the study of Prof. Dr Zl. Penev (1963 - 1974) from the same region found that the same number of positive reactions from epicutaneous testing was observed. In both studies, there were more positive reactions in women. We found a significant increase in the positive reactions to nickel and cobalt in the last 45 years. The positive reactions to nickel are increased 10.3 times and increased 4.9 times to cobalt.Алергичният контактен дерматит (АКД) представлява имунологично-медиирана, възпалителна реакция от забавен (IV) тип при сенсибилизирани към даден алерген индивиди. След настъпване на сенсибилизация на организма, последващата експозиция на алергена, която е над индивидуалния праг на чувствителност води до клиничната изява на алергичен контактен дерматит. Данните на европейската Академия по алергология сочат за значително увеличаване на кожните алергични заболявания. Съобщава се, че от хронични алергични заболявания страдат повече от 150 милиона европейци, като прогнозите са, че през 2025г. се очаква поне половината от европейската популация да бъде засегната от алергични заболявания. Причините се крият във все по-широкия контакт на човешкия организъм с различни алергени, произхождащи от заобикалящата ни среда, промяната в начина на живот, глобалната индустриализация и промяната в микробиома. Целта на настоящия дисертационен труд е многостранно и задълбочено изучаване на разпространението на контактната алергия във Варненски регион, установяване на честотата и особеностите в клиничната картина, диагностиката и профилактиката на алергичния контактен дерматит с оглед очертаване на характерните особености за този регион. Задачите са: да се направи проучване на честотата на контактната алергия във Варненски регион, като се използват данните на епикутанно тестувани пациенти от областта за последните 3 години (2018-2020 година); да се анализират специфичните особености в етиопатогенезата на алергичния контактен дерматит (пол, възрастови групи, професия, атопичен терен); да се посочат основните характеристики в клиничната картина, локализацията, продължителността на оплакванията и особените клинични форми при пациентите от Варненски регион; да се изследва честотата на положителните реакции към отделните алергени и се посочи най - честия сенсибилизатор при тестуваните със стандартна и разширена Европейска серия на пациенти във Варненски регион; да се разгледат детайлно значимите алергени в различните възрастови подгрупи при пациентите от Варненски регион; да се сравнят резултатите за контактната сенсибилизация при пациенти от Варненски регион – ретроспективно и сравнително проучване с данни от проучването на проф. Зл. Пенев за същия регион от 1963-1974 година и сравнително проучване с данните от областите Плевен и Русе за периода 2009 – 2018 година