SLACID - Sparse Linear Algebra in a Column-Oriented In-Memory Database System

Scientific computations and analytical business applications are often based on linear algebra operations on large, sparse matrices. With the hardware shift of the primary storage from disc into memory it is now feasible to execute linear algebra queries directly in the database engine. This paper presents and compares different approaches of storing sparse matrices in an in-memory column-oriented database system. We show that a system layout derived from the compressed sparse row representation integrates well with a columnar database design and that the resulting architecture is moreover amenable to a wide range of non-numerical use cases when dictionary encoding is used. Dynamic matrix manipulation operations, like online insertion or deletion of elements, are not covered by most linear algebra frameworks. Therefore, we present a hybrid architecture that consists of a read-optimized main and a write-optimized delta structure and evaluate the performance for dynamic sparse matrix workloads by applying workflows of nuclear science and network graphs

Topology-aware optimization of big sparse matrices and matrix multiplications on main-memory systems

Since data sizes of analytical applications are continuously growing, many data scientists are switching from customized micro-solutions to scalable alternatives, such as statistical and scientific databases. However, many algorithms in data mining and science are expressed in terms of linear algebra, which is barely supported by major database vendors and big data solutions. On the other side, conventional linear algebra algorithms and legacy matrix representations are often not suitable for very large matrices. We propose a strategy for large matrix processing on modern multicore systems that is based on a novel, adaptive tile matrix representation (AT MATRIX). Our solution utilizes multiple techniques inspired from database technology, such as multidimensional data partitioning, cardinality estimation, indexing, dynamic rewrites, and many more in order to optimize the execution time. Based thereon we present a matrix multiplication operator ATMULT, which outperforms alternative approaches. The aim of our solution is to overcome the burden for data scientists of selecting appropriate algorithms and matrix storage representations. We evaluated AT MATRIX together with ATMULT on several real-world and synthetic random matrices

Phosphorylation of Vasodilator-Stimulated Phosphoprotein (VASP) dampens hepatic ischemia-reperfusion injury

Recent work has demonstrated that the formation of platelet neutrophil complexes (PNCs) affects inflammatory tissue injury. Vasodilator-stimulated phosphoprotein (VASP) is crucially involved into the control of PNC formation and myocardial reperfusion injury. Given the clinical importance of hepatic IR injury we pursued the role of VASP during hepatic ischemia followed by reperfusion. We report here that VASP−/− animals demonstrate reduced hepatic IR injury compared to wildtype (WT) controls. This correlated with serum levels of lactate dehydrogenase (LDH), aspartate (AST) and alanine (ALT) aminotransferase and the presence of PNCs within ischemic hepatic tissue and could be confirmed using repression of VASP through siRNA. In studies employing bone marrow chimeric mice we identified hematopoietic VASP to be of crucial importance for the extent of hepatic injury. Phosphorylation of VASP on Ser153 through Prostaglandin E1 or on Ser235 through atrial natriuretic peptide resulted in a significant reduction of hepatic IR injury. This was associated with a reduced presence of PNCs in ischemic hepatic tissue. Taken together, these studies identified VASP and VASP phosphorylation as crucial target for future hepatoprotective strategies

Bringing Linear Algebra Objects to Life in a Column-Oriented In-Memory Database

Large numeric matrices and multidimensional data arrays appear in many science domains, as well as in applications of financial and business warehousing. Common applications include eigenvalue determination of large matrices, which decompose into a set of linear algebra operations. With the rise of in-memory databases it is now feasible to execute these complex analytical queries directly in a relational database system without the need of transfering data out of the system and being restricted by hard disc latencies for random accesses. In this paper, we present a way to integrate linear algebra operations and large matrices as first class citizens into an in-memory database following a two-layered architectural model. The architecture consists of a logical component receiving manipulation statements and linear algebra expressions, and of a physical layer, which autonomously administrates multiple matrix storage representations. A cost-based hybrid storage representation is presented and an experimental implementation is evaluated for matrix-vector multiplications

Chemical weathering and provenance evolution of Holocene–Recent sediments from the Western Indus Shelf, Northern Arabian Sea inferred from physical and mineralogical properties

We present a multi-proxy mineral record based on X-ray diffraction and diffuse reflectance spectrophotometry analysis for two cores from the western Indus Shelf in order to reconstruct changing weathering intensities, sediment transport, and provenance variations since 13 ka. Core Indus-10 is located northwest of the Indus Canyon and exhibits fluctuations in smectite/(illite + chlorite) ratios that correlate with monsoon intensity. Higher smectite/(illite + chlorite) and lower illite crystallinity, normally associated with stronger weathering, peaked during the Early–Mid Holocene, the period of maximum summer monsoon. Hematite/goethite and magnetic susceptibility do not show clear co-variation, although they both increase at Indus-10 after 10 ka, as the monsoon weakened. At Indus-23, located on a clinoform just west of the canyon, hematite/goethite increased during a period of monsoon strengthening from 10 to 8 ka, consistent with increased seasonality and/or reworking of sediment deposited prior to or during the glacial maximum. After 2 ka terrigenous sediment accumulation rates in both cores increased together with redness and hematite/goethite, which we attribute to widespread cultivation of the floodplain triggering reworking, especially after 200 years ago. Over Holocene timescales sediment composition and mineralogy in two localities on the high-energy shelf were controlled by varying degrees of reworking, as well as climatically modulated chemical weathering

The uncoordinated-5 homolog B receptor affects hepatic ischemia reperfusion injury

Recent evidence has demonstrated additional roles for the neuronal guidance protein receptor UNC5B outside the nervous system. Given the fact that ischemia reperfusion injury (IRI) of the liver is a common source of liver dysfunction and the role of UNC5B during an acute inflammatory response we investigated the role of UNC5B on acute hepatic IRI. We report here that UNC5B+/− mice display reduced hepatic IRI and neutrophil (PMN) infiltration compared to WT controls. This correlated with serum levels of lactate dehydrogenase (LDH), aspartate- (AST) and alanine- (ALT) aminotransferase, the presence of PMN within ischemic hepatic tissue, and serum levels of inflammatory cytokines. Moreover, injection of an anti-UNC5B antibody resulted in a significant reduction of hepatic IR injury. This was associated with reduced parameters of liver injury (LDH, ALT, AST) and accumulation of PMN within the injured hepatic tissue. In conclusion our studies demonstrate a significant role for UNC5B in the development of hepatic IRI and identified UNC5B as a potential drug target to prevent liver dysfunction in the future

Assessment of selected part of sewer network in urbanized area

Cílem diplomové práce je posouzení současného stavu odkanalizování zájmové lokality v Ostravě a návrh možné obnovy nebo rozšíření stokové sítě. Práce je rozdělena na průvodní zprávu, technickou zprávu, hydrotechnické výpočty a výkresovou dokumentaci. Posouzení se skládá ze stanovení stavebně-technického stavu vybraných stok, hydraulického posouzení stokové sítě s návrhem možných opatření a ekonomického zhodnocení těchto opatření. V části, zaměřené na hydrotechnické výpočty, je popsána tvorba hydraulického modelu v programu MIKE URBAN včetně procesu kalibrace a simulací jednotlivých navrhovaných variant obnovy nebo rozšíření stokové sítě zájmové lokality.The aim of the thesis is to assess the current state of sewerage of the site of interest in Ostrava and to suggest a possible renewal or extension of the sewer network. The work is divided into accompanying report, technical report, hydrotechnical calculations and drawing documentation. The assessment consists of determination of the technical state of selected sewers, hydraulic assessment of the sewer network with a proposal of possible measures and economic evaluation of these measures. In the part of hydrotechnical calculations creation of hydraulic model in program MIKE URBAN is described, including process of calibration and simulation of individual proposed variants of renewal or extension of sewer network of the locality of interest.

Characterization of fuel segregation in a fluidized bed by magnetic particle tracking

A Magnetic Particle Tracking (MPT) system is used to experimentally characterize the vertical distribution of fuel particles in a fluidized bed. The measurements are carried out in a fluid-dynamically down-scaled cold unit resembling a 1×1 m2 boiler operating at 850 °C. The MPT system yields spatial and temporal information of the tracer particle with accuracies in the order of 10-3 m and 10-3 s, respectively. The MPT system is used to study how fuel segregation is influenced by physical properties of the fuel (sizes and densities representing different fuel types) and operational conditions, such as fluidization velocity, bed height and pressure drop across the gas distributor. For the range of fluidization velocities investigated, the results show two fuel segregation regimes: 1) a low-velocity mixing-regime, for which the presence of fuel particles at the dense bed surface and splash zone decreases strongly with increased fluidization velocity, and 2) a high-velocity mixing-regime where the presence of fuel at the bed surface and the splash zone increases with fluidization velocity, but with a weaker dependence than in the low-velocity regime. The fluidization velocity separating the two regimes depends on bed height and fuel properties

Study of rehabilitation of the selected part of the sewerage network in Ostrava

Cílem bakalářské práce je zhodnocení současného stavu poznání v oblasti sanace stokových sítí. Práce je rozdělena na teoretickou část a praktickou část. V teoretické části práce je cílem podrobné popsání procesu sanace a uvedení v současnosti nejpoužívanějších sanačních technologií. V praktické části práce je provedena praktická ukázka návrhu sanace na vybraném úseku stokové sítě v Ostravě. Tato část práce je rozčleněna na průvodní a technickou zprávu. V rámci praktické části je provedeno stanovení stavebně-technického stavu vybrané části stokové sítě a dále je proveden návrh sanačních řešení a ekonomické zhodnocení.The aim of the bachelor thesis is to evaluate the current state of knowledge in the area of rehabilitation of sewerage networks. The thesis is divided into theoretical part and practical part. In the theoretical part of the thesis the aim is to describe in detail the process of remediation and presenting the most frequently used rehabilitation technologies. In the practical part of the thesis a practical demonstration of the design of the rehabilitation is carried out on the selected section of the sewerage network in Ostrava. This part of the thesis is broken down into a main text and technical report. Within the practical part, the construction and technical condition of the selected part of the sewer network is assessed, and the design of rehabilitation works, and economic evaluation is carried out.

Interpersonal Change During Inpatient CBASP Treatment: Focus on Group Therapy

Background: The Cognitive Behavioral Analysis System of Psychotherapy (CBASP) has been tailored specifically to the demands of patients with persistent depressive disorder (PDD). According to the CBASP model, PDD patients are supposed to live perceptually disconnected from their social environment, which consequently maintains depression. While initially developed as an individual treatment modality, the adaptation for group therapy yields an important interpersonal space. However, little is known about the specific factors that contribute to patients' benefit from the CBASP group modality. Methods: The analyzed sample comprised N = 87 PDD patients who completed a 12 week multimodal inpatient treatment including 2 weekly CBASP-specific individual and group sessions, respectively, as well as CBASP-unspecific medical contacts, pharmacotherapy and complementary therapies. Group sessions included trainings in situational analysis and interpersonal skills. Interpersonal change over therapy was examined based on the patients' self-perceived interpersonal problems (IIP) and the impact messages as perceived by their individual therapists (IMI). Pre and post-treatment data were compared using within-sample t-tests. Additionally, patients evaluated CBASP group therapy on a feedback form. They were invited to reflect on individual benefits and its helpful and unhelpful aspects. Qualitative content analysis with inductive category development was used to analyze feedback. Inter-rater reliability was computed to confirm categories before summarizing the frequencies of reported factors. Results: Self-perceived interpersonal distress significantly decreased over therapy. Patients reported reduced interpersonal problems and therapists reported more friendly and dominant impact messages. Interestingly, patients who showed a significant depressive symptom reduction described higher change scores. Regarding qualitative data, patients reported five main benefits from group therapy: Gain in social competence, self-confidence, self-reflection, interpersonal dynamics, and optimism/universality. Patients responding to CBASP identified significantly more factors than non-responders. Conclusions: Compared to studies with individual CBASP only, the present findings suggest that CBASP group therapy may contribute to the improvement of interpersonal behavior. Group therapy is discussed as a potential boosting effect for individual CBASP. However, as the present data were collected in a multimodal inpatient setting without competitor, randomized controlled trials are warranted that investigate the specific benefits of the group modality or the combined individual and group therapy over individual CBASP only