Supergravity and Large N Noncommutative Field Theories

We consider systems of Dp branes in the presence of a nonzero B field. We study the corresponding supergravity solutions in the limit where the branes worldvolume theories decouple from gravity. These provide dual descriptions of large N noncommutative field theories. We analyse the phase structure of the theories and the validity of the different description. We provide evidence that in the presence of a nonzero B field the worldvolume theory of D6 branes decouples from gravity. We analyse the systems of M5 branes and NS5 branes in the presence of a nonzero C field and nonzero RR fields, respectively. Finally, we study the Wilson loops (surfaces) using the dual descriptions.Comment: 27 pages, 10 figures, Latex; typos corrected, ref. adde

Dioxins and dioxin-like compounds in meat and meat products

Dioxin and dioxin-like compounds are persistent organic pollutants that received considerable attention in recent years due to their high potential toxicity, wide distribution and extreme stability. Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) mainly occur in the environment as a result of several human activities including combustion, incineration and many other industrial activities, whereas polychlorinated biphenyls (PCBs) congeners were intentionally manufactured and widely used in various fields. Since dioxin and dioxin-like compounds are found in various environmental compartments (air, water, soil, sludge, sediment, food, feed, blood, animal and human tissues), humans could be exposed to them via inhalation, dermal contact or food ingestion. However, 90% of human exposure to dioxin is through food ingestion particularly foods from animals and foods that are rich in fat. In contrast, only low levels have been found in food items of plant origin. Exposure to dioxin compounds is associated with various adverse health problems. However, their toxicity varies dramatically according to the type of dioxin, species of exposed organism, as well as exposure frequency and duration. Dioxins are mainly determined by instrumental chromatographic methods such as GC-HRMS and GC–MS/MS. Many efforts have been made to remove, reduce and prevent these hazardous substances from the environment. However, the best method for reducing human exposure to dioxins and dioxin-like compounds is controlling and minimizing their production. In this article, structures, sources, exposure, toxicity and analysis methods of dioxin and dioxin-like compounds in meat and other foods were reviewed.Dioxin and dioxin-like compounds are persistent organic pollutants that received considerable attention in recent years due to their high potential toxicity, wide distribution and extreme stability. Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) mainly occur in the environment as a result of several human activities including combustion, incineration and many other industrial activities, whereas polychlorinated biphenyls (PCBs) congeners were intentionally manufactured and widely used in various fields. Since dioxin and dioxin-like compounds are found in various environmental compartments (air, water, soil, sludge, sediment, food, feed, blood, animal and human tissues), humans could be exposed to them via inhalation, dermal contact or food ingestion. However, 90% of human exposure to dioxin is through food ingestion particularly foods from animals and foods that are rich in fat. In contrast, only low levels have been found in food items of plant origin. Exposure to dioxin compounds is associated with various adverse health problems. However, their toxicity varies dramatically according to the type of dioxin, species of exposed organism, as well as exposure frequency and duration. Dioxins are mainly determined by instrumental chromatographic methods such as GC-HRMS and GC–MS/MS. Many efforts have been made to remove, reduce and prevent these hazardous substances from the environment. However, the best method for reducing human exposure to dioxins and dioxin-like compounds is controlling and minimizing their production. In this article, structures, sources, exposure, toxicity and analysis methods of dioxin and dioxin-like compounds in meat and other foods were reviewed

On Superconnections and the Tachyon Effective Action

We propose a form of the effective action of the tachyon and gauge fields for brane-antibrane systems and non-BPS Dp-branes, written in terms of the supercurvature. Kink and vortex solutions with constant infinite gauge field strength reproduce the exact tensions of the lower-dimensional D-branes. We discuss the relation to BSFT and other models in the literature

Microarray Analysis of Late Response to Boron Toxicity in Barley (Hordeum vulgare L.) Leaves

DNA microarrays, being high-density and high-throughput, allow quantitative analyses of thousands of genes and their expression patterns in parallel. In this study, Barley1 GereChip was used to investigate transcriptome changes associated with boron (B) toxicity in a sensitive barley cultivar (Hordeum vulgare L. cv. Hamidye). Eight-day-old aseptically grown seedlings were subjected to 5 or 10 mM boric acid (B(OH)(3)) treatments for 5 days and expression profiles were determined with DNA microarrays using total RNA from leaf tissues. Among the 22,840 transcripts - each represented with a probe set on the GeneChip - 19,424 probe sets showed intensity values greater than 20(th) percentile in at least one of the hybridizations. Compared to control (10 mu M B(OH)(3)), 5 mM B(OH)(3) treatment resulted in differential expression of 168 genes at least by twofold. Moreover, 10 mM B(OH)(3) treatment resulted in at least twofold induction or reduction in expression of 312 transcripts. Among these genes, 37 and 61 exhibited significantly (P <0.05) altered levels of expression under 5 and 10 mM B(OH)(3) treatments, respectively. Differentially expressed genes were characterized using expression-based clustering and HarvEST:Barley. Investigations of expression profiles revealed that B toxicity results in global changes in the barley transcriptome and networks of signaling or molecular responses. A noticeable feature of response to 8 was that it is highly interconnected with responses to various environmental stresses. Additionally, induction of jasmonic acid related genes was found to be an important late response to B toxicity. Determination of responsive genes will shed light on successive studies aiming to elucidate molecular mechanism of B toxicity or tolerance. To the best of our knowledge, this is the first report on global expression analysis of barley seedlings under B toxicity

Multiple Instance Learning for Heterogeneous Images: Training a CNN for Histopathology

Multiple instance (MI) learning with a convolutional neural network enables end-to-end training in the presence of weak image-level labels. We propose a new method for aggregating predictions from smaller regions of the image into an image-level classification by using the quantile function. The quantile function provides a more complete description of the heterogeneity within each image, improving image-level classification. We also adapt image augmentation to the MI framework by randomly selecting cropped regions on which to apply MI aggregation during each epoch of training. This provides a mechanism to study the importance of MI learning. We validate our method on five different classification tasks for breast tumor histology and provide a visualization method for interpreting local image classifications that could lead to future insights into tumor heterogeneity

Hydrodynamics and the Detection of the QCD Axial Anomaly in Heavy Ion Collisions

We consider the experimental implications of the axial current triangle diagram anomaly in a hydrodynamic description of high density QCD. We propose a signal of an enhanced production of spin-excited hadrons in the direction of the rotation axis in off-central heavy ion collisions.Comment: 15 pages, 19 figures; v2: refs added, minor changes to the plots; v3, comments adde

Paradoxical effects of lipolysis on the lipid oxidation in meat and meat products

Lipolysis in meat and meat products is a phenomenon involving hydrolysis of lipids, notably via enzymatic catalysis that takes place even postmortem. During refrigerated and frozen storage of meat, in particular fish, endogenous lipolytic enzymes actively degrade triacylglycerols and phospholipids resulting in accumulation of free fatty acids and other hydrolytic products. A classical conjecture suggests that lipolysis enhances lipid oxidation which is involved in quality deterioration of fresh meat and, to some degrees, flavor development of certain meat products. Recent studies (&lt;5 years) have shown that under some circumstances, lipolysis of certain lipolytic enzymes can inhibit lipid oxidation in muscle models, which provides more insight in lipid oxidation mechanisms in muscle matrices as well as implies potential strategies for improving meat quality. This review will discuss such paradoxical effects and potential mechanisms of lipolysis on lipid oxidation in meat and meat products