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Pemphigus vulgaris (PV) is an autoimmune bullous dermatosis with uneven geographic distribution and higher incidence in certain populations. In previous studies, a relatively high incidence of PV was reported in Bulgaria (0.47/100,000/year) comparable to that in other countries. The genetic background was considered responsible for the disease susceptibility, and multiple reports have proven PV to be an HLA-associated condition. The aim of our study was to analyze the role of genetic factors in the development of PV in Bulgaria. HLA genotyping was performed in 56 PV patients, ethnic Bulgarians whose diagnosis was confirmed based on clinical, histological, and immunofluorescent findings. The control group consisted of 204 healthy individuals from the Bulgarian population without evidence for HLA-associated autoimmune diseases. HLA-A,-B,-DRB1,-DQB1 analysis was performed by PCR-SSP. Our results revealed predisposing associations with DRB1*14, DRB1*04:02, and B*38, B*55, while allele DRB1*03:01 and the corresponding haplotypes were significantly decreased in the PV patients. The predisposing role of these alleles has been observed in other populations. All reported predisposing DRB1 alleles have the same amino acids at key positions of the beta chain of the HLA molecules, 26 (Phe), 67 (Leu or Ileu), 70 and 71 (hydrophobic AA: Gln, Arg, Asp, or Glu), and 86 (Val), which is important for the selective presentation of desmoglein 3 peptides. Additionally, specific alleles HLA-A*01 and DRB1*11 were identified with decreased frequencies in the patients’ group, the last one being a common protective allele for autoimmune diseases in the Bulgarian population. The elucidation of the role of genetic factors for the development of pemphigus will help explain its higher incidence and clinical variability in certain populations.

A fine characterization of the HLA molecular profiles of populations from distinct origins and ethnical back-grounds is essential for both clinical issues in histocompatibility and transplantation and fundamental research in population and evolutionary genetics. Recent developments of high throughput sequencing technologies(including NGS) have allowed generating high resolution data at most HLA loci for thousands of individuals at rather accessible costs, leading many laboratories to type or retype large population samples with the aim to fill gaps in the landscape of HLA-typed populations, thereby significantly improving the quality of the molecular data available. Under the umbrella of the EFI Population Genetics Working Group and the Population Genetics, Anthropology and Evolution (PGAE) Component of the 18th International HLA & Immunogenetics Workshop, as many as 30 laboratories were involved in a collective effort to improve the HLA molecular map of a large geographic region encompassing Europe, North Africa, West Asia and South Asia and also including populations of European and mixed descent from North, Central and South America. In addition to 15populations represented by very large samples (in total more than 270, 000 individuals) typed at the 2nd-fieldlevel of resolution, the final dataset includes20 populations sequenced by NGS and reported at the4th-field level for up to 11 HLA loci. Statistical and graphical analyses of this newly generated dataset, combined with previously available worldwide data, reveal a much more precise topography of the HLA molecular landscape across populations and hence also improve the reference datasets used in histocompatibility and transplantation. The observed HLA molecular diversity is further contrasted to that of equivalent MHC-Patr loci analyzed in several chimpanzee cohorts (with implementation of new sequence data), enabling novel interpretations of the genetic history and evolution of the secrucial immune genes.

The 17(th) International HLA and Immunogenetics Workshop (IHIW) organizers conducted a Pilot Study (PS) in which 13 laboratories (15 groups) participated to assess the performance of the various sequencing library preparation protocols, NGS platforms and software in use prior to the workshop. The organizers sent 50 cell lines to each of the 15 groups, scored the 15 independently generated sets of NGS HLA genotyping data, and generated “consensus” HLA genotypes for each of the 50 cell lines. Proficiency Testing (PT) was subsequently organized using four sets of 24 cell lines, selected from 48 of 50 PS cell lines, to validate the quality of NGS HLA typing data from the 34 participating IHIW laboratories. Completion of the PT program with a minimum score of 95% concordance at the HLA-A, HLA-B, HLA-C, HLA-DRB1 and HLA-DQB1 loci satisfied the requirements to submit NGS HLA typing data for the 17(th) IHIW projects. Together, these PS and PT efforts constituted the 17(th) IHIW Quality Control project. Overall PT concordance rates for HLA-A, HLA-B, HLA-C, HLA-DPA1, HLA-DPB1, HLA-DQA1, HLA-DQB1, HLA-DRB1, HLA-DRB3, HLA-DRB4 and HLA-DRB5 were 98.1%, 97.0% and 98.1%, 99.0%, 98.6%, 98.8%, 97.6%, 96.0%, 99.1%, 90.0% and 91.7%, respectively. Across all loci, the majority of the discordance was due to allele dropout. The high cost of NGS HLA genotyping per experiment likely prevented the retyping of initially failed HLA loci. Despite the high HLA genotype concordance rates of the software, there remains room for improvement in the assembly of more accurate consensus DNA sequences by NGS HLA genotyping software.

Обектът на изследването е музикалният живот в град Лом и развитието му в конкретния разглеждан период – втората половина на XX век, т.е. в неговият разцвет. Време с фундаментално значение, отличило се с появата на първите театрални представления още преди Освобождението и създаването на първото читалище.В глава първа разглеждам първите сериозни прояви на национално самосъзнание у българите в Лом свързани с дейността на оформилата се около Кръстъо Пишурка и Никола Първанов просветителска група от талантливи интелигенти. Глава втора е съсредоточена върху възникването на културният живот и факторите предопределящи неговото развитие. един от които е важното географско разположение, което заема града. В Трета глава проследявам опитите за създаване на професионален оперетен театър и развитието му през годините.В труда проследявам историята на оперетното изкуство в град Лом, и рзагклеждам отблизо неговите представители в лицето на артисти, диригенти, балетисти и оркестранти. Отделям специално внимание на Детската музикална школа в града чиито основател е проф. Йордан Гаврилов. Която вече повече от 60 години е продължител на музикалните традиции в град Лом.Разглеждам създаването и развитието на балетната школа при НЧ „Постоянство 1856г” с основоположници балетиста и педагог Иван Кирилов и Руска Ванова. В раздела озаглавен „Наследниците” разглеждам личностите допринесли за развитието на музикалният живот в града и наследници на делото на учителя Белчо Белчев, Петър Евстатиев The subject of the study is the musical life in the town of Lom and its development in the specific period under review - the second half of the 20th century, ie. in its bloom. A time of fundamental significance distinguished by the appearance of the first theatrical performances before the Liberation and the establishment of the first community center. In the first chapter I examine the first serious manifestations of national self-consciousness among the Bulgarians in Lom related to the activity of the enlightenment group Krasto Pishurka and Nikola Parvanov by talented intelligentsia. Chapter Two focuses on the emergence of cultural life and the factors determining its development. one of which is the important geographic location occupied by the city. In the third chapter I follow the attempts to create a professional operetta theater and its development over the years. In the work I follow the history of the operetta art in the city of Lom, and I closely look at its representatives in the face of artists, conductors, ballet dancers and orchestras. I pay special attention to the Children's Music School in the city, whose founder is Prof. Yordan Gavrilov. For more than 60 years I have been continuing the musical traditions in the town of Lom. I look at the creation and development of the ballet school with the "Standing 1856" NS with the founders of the ballet and pedagogue Ivan Kirilov and Ruska Vanova. In the section titled "The Heirs"

The paper presents results from unplanned factor analysis of experimental data for the electrical characteristics of soils with different humidity, determined at different frequencies. Equations for determining of the soil resistivity and dielectric permittivity depending on their value at 50Hz, different humidity and density of the soil for frequencies from 100kHz to 1MHz have been obtained as a result from a two-variable regression analysis. Verification of the results authenticity and a graphical comparison between the experimental and computing results have been performed.

Systems for generation of high-voltage discharge pulses (SGHVDP) in water, based on capacitive energy accumulation, are widely used in different technological applications, including on ships. Their usage demands control of the discharge pulses frequency in terms of capacity change of the work capacitor battery and the voltage to which it is charged, which is often performed by a thyristor switch. Disadvantages of this type of control are the high level of harmonics and low values of the power factor cos

In recent years, energy efficiency issues have become increasingly popular. This is due to the increase of both the electricity consumption and the price of the basic energy sources. An approach for satisfaction the increased requirements for the quality of electrical power is related to the regulation of the amplitude of the supply voltage, which is changing in time. An effective method for limiting the supply voltage range can be realized by using autotransformer discrete alternating voltage regulators. The paper is dedicated to the exploration of the loading of the autotransformer discrete alternating voltage regulators at different ranges of commutation (different supply voltages) and the change of the efficiency coefficient. An automated computer program has been developed, which allows the simulation of the processes in the discrete regulators in the MATLAB environment. An experimental check of a prototype was performed showing a good correspondence with the data from the simulated processes.

Various technological applications require formation of a high voltage discharge pulse in liquid medium. The process is accompanied with generation of UV radiation, production of chemically active species in the medium, intensive increase of the temperature of the discharge channel, generation of shock waves, etc. The last are caused by the release of large amount of energy especially at the beginning of the discharge process. The experimental system used for generation of a high voltage pulse discharge is based on capacitive energy accumulation. The formation of the pulse in the liquid considering the specifics of the process in such medium also affects on the processes in the electrical circuits in the device-loading of the elements, creating electromagnetic disturbances in the power supply system, generation of electromagnetic field around the device. The paper is dedicated to investigation of a system with capacitive energy storage for generation of a high voltage periodically attenuating pulse discharge The purpose is to be measured the electric and magnetic fields generated during the charging and discharging processes near the system for assessment of the device electrical safety for the personnel. © 2017 Nikola Vaptsarov Naval Academy. All rights reserved.

Big data collections in many Scientific domains have inherently rich spatial and geospatial features. Spatial location is among the core aspects of data in Earth observation sciences,astronomy,and seismology to name a few. The NLeSC project aims at developing software technology and tools for building of generic geo-spatial analysis systems with focus on three dimensional (3D) city models. The project has three major partners, VU Geographic Information Systems (GIS) group / Geodan represented by Prof. Henk Scholten, CWI Database group / MonetDB solutions represented by Prof. Martin Kersten and TUDelft Geo-information for Crisis Management group represented by Prof. Sisi Zlatanova. Digital 3D city models play a crucial role in research of urban phenomena; they form the basis for e.g. flow simulations (e.g. wind streams, water runoff and heat island effects), urban planning, analysis of underground formations, etc. Urban scenes consist of large collections of complex objects which have rich semantic properties, such as materials, colors, etc. Modeling and storing these properties indicating the relationships between them is best handled in a relational database. Database management systems (DBMSs) are a well-established solution when it comes to archiving, filtering, analysis, and correlation of large data collections. Ability to perform analysis near data is one of the key requirements identified by the 4th Paradigm to handle the data deluge. A single spatial DBMS offers functionality for geo-spatial modeling and management of semantic properties in one place, thus avoiding the need for multiple software tools associated with high volume data transfer and format transformations. The provision of spatial and geo-spatial features in database systems needs to be extended and brought to maturity to fulfill the requirements of real-world scientific applications. A class of DBMSs, called column-stores, have proven efficiency for analytic applications on extremely large data sets. Column stores have become the de-facto standard for managing large data warehouses. Although column stores have a proven track record in business analytics, their pros- and cons- for GIS applications are not yet well understood. Such core technology extensions for geo-spatial analytics are beneficial for public as well as private sector. Municipalities and spatial data providers can both extend and enhance their offerings of data products and services. Several municipalities have expressed an interest in using the technology in their urban projects for management and analysis of geo-spatial data collections, and the port of Rotterdam will be used as a driving application during the design and implementation. A Port of Rotterdam’s 3D GIS has been built to aid various multi-stakeholder construction projects where new structures are built in, on top of and around the existing port (underground)infrastructure. Extending and modifying the port is challenging as it is home to many different companies that often cover extensive areas and manage vast infrastructures such roads, pipes and cables. The port thus requires a 3D GIS that is able to store all harbor assets and analyze existing assets with future interventions and detect conflicts. The 3D GIS currently being built is aimed at collecting data from different sources and formats and converting it to a common format to enable 3D operations and analyses such as 3D intersections. The development relies as much as possible on existing open-source tools and libraries, and be distributed through an open-source product to maximize the take-up in education and science. It will be offered as an associated NLeSC technology.

Devices, using electrical discharges in water for environmental purposes, on board of ships are used in: liquid waste and ballast water treatment, water cleaning, dye removal, sterilization of drinking water. Such discharges may also be used for cleaning of surfaces from scale. At pulse electrical discharges in water are produced chemically active species in the medium. In the water, the electron impacts can lead to dissociation and production of atomic oxygen (O) and hydroxyl radicals (OH). Simultaneously, discharges create also UV radiation and shock waves. The chemical species O and OH are transient, but they have very strong oxidative properties compared to the classical neutral oxidant molecules. The occurrence of electrical discharge in water depends on many parameters, such as discharge voltage, conductivity of the medium, inductance of the electric circuit, distance between the electrodes, depth of the discharge (pressure), temperature and others. In the present article is discussed the influence of the water temperature in which the discharge occurs over the water resistance change.

Under the formation of high voltage discharges in a liquid medium many physical and chemical processes occur, which depend on many different factors (characteristic of the electric field, composition of the liquid medium, external parameters such as temperature, pressure, etc.). Considering the dynamics of these processes, the purpose of the present work is experimental study and analysis of the influence of the temperature and the energy characteristics on the liquid medium resistance change at the formation of a high-voltage discharge pulse. The obtained results and dependencies can be used for design of devices for formation of such discharges in liquids for different technological applications.

In case of direct lightning stroke, pulse currents flow through the earthing system, which defines a different approach in the modeling and study of the processes in it. The practical interest is aimed at determining the potentials in the area of the earthing system and the possible touch and foot voltages.The purpose of the paper is to present a model scheme of the earthing system for study of wave processes.

Big data collections in many scientific domains have inherently rich spatial and geo-spatial features. Spatial location is among the core aspects of data in Earth observation sciences, astronomy, and seismology to name a few. The goal of our project is to design an efficient data management layer for a generic geo-spatial analysis system with focus on three dimensional (3D) city models. Digital 3D city models play a crucial role in research of urban phenomena; they form the basis for flow simulations (e.g. wind streams, water runoff and heat island effects), urban planning, and analysis of underground formations. Urban scenes consist of large collections of semantically rich objects which have a large number of properties such as material and color. Modeling and storing these properties indicating the relationships between them is best handled in a relational database. The provision of spatial and geo-spatial features in database systems needs to be extended and brought to maturity to fulfill the requirements of real-world scientific applications. A class of DBMSs, called column-stores, have proven efficiency for analytic applications on extremely large data sets. Column stores have become the de-facto standard for managing large data warehouses. Although column stores have a proven track record in business analytics, their pros- and cons- for GIS applications are not yet well understood. Our goal is to have a spatial DBMS which iteratively loads data from different sources and converts it into a common format to enable 3D operations and analyses, such as 3D intersections, and semantic properties management.

Dealing with LIDAR data in the context of database management systems calls for a re-assessment of their functionality, performance, and storage/processing limitations. The territory for efficient and scalable processing of LIDAR repositories using GIS enabled database systems is still largely unexplored. Bringing together hard core database management experts and GIS application developers is a sine qua non to advance the state of the art. In particular to assess the relative merits of both traditional row-based database engines and the modern column-oriented database engines.

Dealing with LIDAR data in the context of database management systems calls for a re-assessment of their functionality, performance, and storage/processing limitations. The territory for efficient and scalable processing of LIDAR repositories using GIS enabled database systems is still largely unexplored. Bringing together hard core database management experts and GIS application developers is a sine qua non to advance the state of the art. In particular to assess the relative merits of both traditional row-based database engines and the modern column-oriented database engines.

We present a real-time wildfire monitoring service that exploits satellite images and linked geospatial data to detect hotspots and monitor the evolution of fire fronts. The service makes heavy use of scientific database technologies (array databases, SciQL, data vaults) and linked data technologies (ontologies, linked geospatial data, stSPARQL) and is implemented on top of MonetDB and Strabon. The service is now operational at the National Observatory of Athens and has been used during the previous summer by emergency managers monitoring wildfires in Greece.

Various technological applications require formation of high voltage discharge pulse in liquid medium. Due to the parasitic inductivities at capacitive energy storage, the character of the discharge pulse most often is periodically attenuating. Management of the moment when the discharge occurs assumes usage of high voltage controllable switches. The present work is dedicated to analysis of the electrical processes in a discharge circuit with two discharge gaps, comparison with respect to the used high voltage controllable switch - a trigatron (controllable air discharge) and a thyratron and modeling of the high voltage periodical discharge in the liquid medium.

The usage of high voltage discharge in liquid finds many technological applications. Control of the moment when the discharge occurs in systems with capacitive energy storage, suggests the usage of a high voltage controllable switch, most often trigatron or thyratron, i.e. gas discharge occurs. The present work is dedicated to modeling of the discharge processes, arising in liquid medium and control by a high-voltage controllable switch-thyratron.

The usage of high voltage discharge in liquid has many technological applications. For realization of high voltage pulse discharge in liquid are used circuits with two discharge gaps, and one of them functions as a controllable high voltage switch. At capacitive energy storage and considering the parasitic inductances the discharge pulse most often has periodically attenuating character. The current work is dedicated to experimental study of high voltage discharge in a circuit with two discharge gaps with the usage of a controllable air discharger - trigatron. On the basis of the received results is performed analysis and is created a model of the resistance change at discharge in time, regarding the capacitance of the capacitor battery and the voltage, which it is charged to.

Distributed processing commonly requires data spread across machines using a priori static or hash-based data allocation. In this paper, we explore an alternative approach that starts from a master node in control of the complete database, and a variable number of worker nodes for delegated query processing. Data is shipped just-in-time to the worker nodes using a need to know policy, and is being reused, if possible, in subsequent queries. A bidding mechanism among the workers yields a scheduling with the most efficient reuse of previously shipped data, minimizing the data transfer costs. Just-in-time data shipment allows our system to benefit from locally available idle resources to boost overall performance. The system is maintenance-free and allocation is fully transparent to users. Our experiments show that the proposed adaptive distributed architecture is a viable and flexible alternative for small scale MapReduce-type of settings.

LEDs have specific testing requirements: stability and pulsations of the current, modulations of the crystal, etc. For some cases of power supply, LEDs are implemented in specialized integrated circuits with defined internal parameters. At the current research, for a definite integrated circuit and different connections of LEDs in the matrix, are studied some influences of main parameters and dependencies between quantities of the specialized integrated circuit internal structure for LED drivers with a step-down pulse converter topology (topology “visk”). The examined influences are over the parameters of externally connected to the driver elements as well as over some of its characteristics.

For different topologies of drivers for LEDs and connection configurations of the LED matrix is performed comparative evaluation of the scheme parameters, losses, energy indicators and their main characteristics depending on the supply voltage. On the basis of the conducted analysis are defined energy effective topologies of drivers and ways of LEDs connection in a matrix

Recently, the usage of high-frequency transverse discharge in technologies for treatment of liquid fluids presents practical interest because: the discharge is characterized by higher stability; reactive elements can be used as a passive load and efficiency coefficient increases; there is symmetric energy dissipation; electrodes with dielectric coating can be used, which solves the problems with their sputtering.The work is devoted to study of the possibilities for application of single circuit generators with automatic pre-voltage and inductive-capacitive matching converter for excitation of a transverse discharge and control of its parameters according to the technological application.

Most purposefully, the usage of electrical discharge is related to its development in a specific, artificially created medium – a discharge element.Due to the specifics of the discharge elements, they are connected as a load to the power supply grid by regulating apparatuses.The work is dedicated to a comparative study between single-circuit and double-circuit regulating apparatuses for control of a direct current discharge with respect to the stability of the discharge current and the power parameters of the regulating apparatuses.

There exist different applications based on high-voltage discharge in liquid medium. Often the high voltage discharge is formed in a discharge circuit which comprises an operating capacitor battery and attached to it high-voltage controllable switch and the discharge gap in the liquid medium. In the present work are studied experimentally the characteristics of the high-voltage discharge in water with the usage of a high-voltage controllable switch, realized as a controllable air discharger - trigatron.

Генераторите за формиране на високоволтов разряден импулс са базирани на зарядна верига за капацитивно натрупване на енергия и разрядна верига с ключов елемент, най-често управляем въздушен разрядник. Работата е посветена на изследване на комутационните възможности на триелектроден управляем въздушен разрядник с две различни в пространството газоразрядни междини, възникващи последователно във времето и относими към появата на разряд и последващо формиране на високоволтовия разряден импулс. Generators for formation of a high voltage discharge pulse are based on a charge circuit for capacitive energy accumulation and a discharge circuit with a switching element, most often – a controllable air discharger. In the paper are studied the commutation capabilities of a three-electrode controllable air discharger with two gas discharge gaps different in space, which occur consecutively in time and refer to the appearance of the discharge and subsequent formation of a high voltage discharge pulse.

Many technological processes refer to formation of high voltage pulses in liquid medium. The high electrical conductivity of this medium imposes usage of switches in the high voltage circuit – most often controlled dischargers. The paper is dedicated to modelling of the electrical processes in a high voltage circuit with two discharge gaps and defining of the formed discharge pulse parameters. The analytically obtained results are compared to experimental ones from a prototype.

Параметрите на газоразрядната плазма и електрическите режими на апаратите за управление на разряда са взаимно зависими и влияещи се. Разнообразието и спецификата на газоразрядните елементи, съобразно приложението им изисква познаване на честотните им свойства за реализация на структурно-параметричния синтез на устройствата за управлението им. В работата е проведено моделиране и аналитично и експериментално изследване за конкретен газоразряден елемент.

The realization of pulse discharge in liquid medium requires the usage of devices which can adopt the parameters of the supply network to the specifics of the load. For the development of such devices it should be possible to assess the controlled parameters and to define requirements for the elements in the respective circuits. In the present work for an unified schematic solution are suggested models and analyses of the electrical processes is conducted. A comparison between the analytical and experimental results is done for a developed prototype.

Modern scientific instruments such as satellites, on-ground antennas, and simulators collect large volumes of data. For example, instruments monitoring the environment emit streams of environmental sensor readings, particle colliders produce streams of particle collision data, and software telescopes such as LOFAR33 produce very voluminous digitized radio signals. The measurement data is normally produced as streams rather than formats stored in conventional database tables. A stream has the property that data is ordered in time, and the data volume is potentially unlimited. Scientists perform a wide range of on-line analyses over the data streams. A conventional approach to data management using a relational database management system (DBMS) has the disadvantage that streaming data has to be loaded into a database before it can be queried and analyzed. If the data rate of a stream is too high, it will be impossible for the DBMS to load the streaming data fast enough. This creates backlogs of unanalyzed data, and the high data volume produced by scientific instruments can even be too large to store and process.2 Furthermore, offline data processing prevents timely analysis of interesting natural events as they occur.

Automatically recycling (intermediate) results is a grand challenge for state-of-the-art databases to improve both query response time and throughput. Tuples are loaded and streamed through a tuple-at-a-time processing pipeline avoiding materialization of intermediates as much as possible. This limits the opportunities for reuse of overlapping computations to DBA-defined materialized views and function/result cache tuning. In contrast, the operator-at-a-time execution paradigm produces fully materialized results in each step of the query plan. To avoid resource contention, these intermediates are evicted as soon as possible. In this paper we study an architecture that harvests the by-products of the operator-at-a-time paradigm in a column store system using a lightweight mechanism, the recycler. The key challenge then becomes selection of the policies to admit intermediates to the resource pool, their retention period, and the eviction strategy when facing resource limitations. The proposed recycling architecture has been implemented in an open-source system. An experimental analysis against the TPC-H ad-hoc decision support benchmark and a complex, real-world application (SkyServer) demonstrates its effectiveness in terms of self-organizing behavior and its significant performance gains. The results indicate the potentials of recycling intermediates and charters a route for further development of database kernels.

Докладът представя прилагане на електронна форма на обучение в допълнение към класическите форми на редовно и задочно обучение в Електротехнически факултет на Технически университет - Варна.

Формирането на импулсен разряд в течна среда с различни технологични приложения изисква възможности за изменение на параметрите на разрядния импулс в широк диапазон. Това може да се постигне ако в зарядния преобразувател има две вериги за управление – променливотоков регулатор на входа и паралелен стабилизатор на изхода. За високоволтови вериги активният регулиращ елемент на паралелния стабилизатор може да бъде само хибриден лампово-транзисторен. В работата са изследвани коефициентът на стабилизация и мощността разсейвана от хибридния регулиращ елемент.

Many technological processes are related to the form of periodic discharge pulses and assume the presence of systems (converters) for capacitive energy accumulation. The dependency of the discharge pulses parameters from the structure of the converter and the supply network parameters necessitates the modeling such circuits and analysis of the electrical processes in them, which present the object of this article. The results from the analysis give a possibility for designing such converters with compliance to certain application demands.

This paper presents our experiences in porting the Sloan Digital Sky Survey(SDSS)/ SkyServer to the state-of-the-art open source database system MonetDB/SQL. SDSS acts as a well-documented benchmark for scientific database management. We have achieved a fully functional prototype for the personal SkyServer, to be downloaded from our site. The lessons learned are 1) the column store approach of MonetDB demonstrates a great potential in the world of scientific databases. However, the application also challenged the functionality of our implementation and revealed that a fully operational SQL environment is needed, e.g. including persistent stored modules; 2) the initial performance is competitive to the reference platform, MS SQL Server 2005, and 3) the analysis of SDSS query traces hints at several techniques to boost performance by utilizing repetitive behavior and zoom-in/zoom-out access patterns, that are currently not captured by the system.

The comparison of different methods for chimerism analysis after allogeneic stem cell transplantation.