Wild Pfister forms over Henselian fields, K-theory, and conic division algebras

The epicenter of this paper concerns Pfister quadratic forms over a field $F$ with a Henselian discrete valuation. All characteristics are considered but we focus on the most complicated case where the residue field has characteristic 2 but $F$ does not. We also prove results about round quadratic forms, composition algebras, generalizations of composition algebras we call conic algebras, and central simple associative symbol algebras. Finally we give relationships between these objects and Kato's filtration on the Milnor $K$-groups of $F$

The Gag Cleavage Product, p12, is a Functional Constituent of the Murine Leukemia Virus Pre-Integration Complex

The p12 protein is a cleavage product of the Gag precursor of the murine leukemia virus (MLV). Specific mutations in p12 have been described that affect early stages of infection, rendering the virus replication-defective. Such mutants showed normal generation of genomic DNA but no formation of circular forms, which are markers of nuclear entry by the viral DNA. This suggested that p12 may function in early stages of infection but the precise mechanism of p12 action is not known. To address the function and follow the intracellular localization of the wt p12 protein, we generated tagged p12 proteins in the context of a replication-competent virus, which allowed for the detection of p12 at early stages of infection by immunofluorescence. p12 was found to be distributed to discrete puncta, indicative of macromolecular complexes. These complexes were localized to the cytoplasm early after infection, and thereafter accumulated adjacent to mitotic chromosomes. This chromosomal accumulation was impaired for p12 proteins with a mutation that rendered the virus integration-defective. Immunofluorescence demonstrated that intracellular p12 complexes co-localized with capsid, a known constituent of the MLV pre-integration complex (PIC), and immunofluorescence combined with fluorescent in situ hybridization (FISH) revealed co-localization of the p12 proteins with the incoming reverse transcribed viral DNA. Interactions of p12 with the capsid and with the viral DNA were also demonstrated by co-immunoprecipitation. These results imply that p12 proteins are components of the MLV PIC. Furthermore, a large excess of wt PICs did not rescue the defect in integration of PICs derived from mutant p12 particles, demonstrating that p12 exerts its function as part of this complex. Altogether, these results imply that p12 proteins are constituent of the MLV PIC and function in directing the PIC from the cytoplasm towards integration

Disentangling Relevance from Reliability in Value Relevance Tests

The literature shows that during the COVID-19 pandemic, the value relevance of earnings decreased. Traditionally, the literature measures value relevance using the relationship between stock returns and earnings. However, these tests are, in fact, “joint tests of relevance and reliability”. This caveat can distort the measurement of relevance, especially during the COVID-19 pandemic where the exceptional level of uncertainty could have affected relevance and reliability to different extents. This study disentangles reliability and relevance by extending the value relevance test. We use this extended test to examine firm categories in two dimensions: profits versus losses and intensive versus scarce use of accounting estimates. The results show that reliability and relevance are complementary when both are sufficiently high, but reliability has no significant impact on the usefulness of earnings when relevance is weak

Disentangling Relevance from Reliability in Value Relevance Tests

The literature shows that during the COVID-19 pandemic, the value relevance of earnings decreased. Traditionally, the literature measures value relevance using the relationship between stock returns and earnings. However, these tests are, in fact, “joint tests of relevance and reliability”. This caveat can distort the measurement of relevance, especially during the COVID-19 pandemic where the exceptional level of uncertainty could have affected relevance and reliability to different extents. This study disentangles reliability and relevance by extending the value relevance test. We use this extended test to examine firm categories in two dimensions: profits versus losses and intensive versus scarce use of accounting estimates. The results show that reliability and relevance are complementary when both are sufficiently high, but reliability has no significant impact on the usefulness of earnings when relevance is weak

Data comparing the plasma levels of procollagen C-proteinase enhancer 1 (PCPE-1) in healthy individuals and liver fibrosis patients

This article provides a protocol for determination of human procollagen C-proteinase enhancer 1 (PCPE-1) concentrations by ELISA. The inter-assay and intra-assay coefficients of variability are given and so are the average plasma concentrations of PCPE-1 in healthy (control) individuals and liver fibrosis patients

Network Analysis of Rat Spatial Cognition: Behaviorally-Established Symmetry in a Physically Asymmetrical Environment

<div><h3>Background</h3><p>We set out to solve two inherent problems in the study of animal spatial cognition (i) What is a “place”?; and (ii) whether behaviors that are not revealed as differing by one methodology could be revealed as different when analyzed using a different approach.</p> <h3>Methodology</h3><p>We applied network analysis to scrutinize spatial behavior of rats tested in either a symmetrical or asymmetrical layout of 4, 8, or 12 objects placed along the perimeter of a round arena. We considered locations as the units of the network (nodes), and passes between locations as the links within the network.</p> <h3>Principal Findings</h3><p>While there were only minor activity differences between rats tested in the symmetrical or asymmetrical object layouts, network analysis revealed substantial differences. Viewing ‘location’ as a cluster of stopping coordinates, the key locations (large clusters of stopping coordinates) were at the objects in both layouts with 4 objects. However, in the asymmetrical layout with 4 objects, additional key locations were spaced by the rats between the objects, forming symmetry among the key locations. It was as if the rats had behaviorally imposed symmetry on the physically asymmetrical environment. Based on a previous finding that wayfinding is easier in symmetrical environments, we suggest that when the physical attributes of the environment were not symmetrical, the rats established a symmetric layout of key locations, thereby acquiring a more legible environment despite its complex physical structure.</p> <h3>Conclusions and Significance</h3><p>The present study adds a behavioral definition for “location”, a term that so far has been mostly discussed according to its physical attributes or neurobiological correlates (e.g. - place and grid neurons). Moreover, network analysis enabled the assessment of the importance of a location, even when that location did not display any distinctive physical properties.</p> </div

Building a network of places.

<p>The rationale for establishing the criterion of 12 cm diameter and the transformation of stopping coordinates into a network is illustrated for one rat. a. <i>Stopping coordinates: -</i> these are as the x-y coordinates of a single rat, as extracted from the tracking system (Ethovision). The large black circle represents the arena perimeter, each red dot represents a stopping coordinate at which the rat stopped for one second or longer, and the black squares represent the location of the objects. b. <i>Nodes under the application of a 12-cm circle around the additional stopping coordinate:-</i> As shown, with this diameter the nodes (circles) coincide with the objects and behavior. c. <i>Nodes under the application of a 9-cm circle around the additional stopping coordinate:-</i> As shown, with this diameter stopping coordinates around the same object split into several nodes, resulting in a mismatch between behavior and nodes. d. <i>Nodes under the application of a 14-cm circle around the additional stopping coordinate:-</i> As shown, with this diameter the bottom node encompasses the stopping coordinates of two objects (see the red dots of these objects in a.). e. <i>Topologic graph:-</i> The presentation of the network after the transformation of stopping coordinates into nodes (red circles). Arrows between nodes represent the links (passes) between nodes. Note that the location of a red circle does not represent the physical location of that node. Likewise, the circles that represent the nodes in b-d do not represent the real size of the node but the number of stopping coordinates included in that node.</p