Umbilic hypersurfaces of constant sigma-k curvature in the Heisenberg group

We study immersed, connected, umbilic hypersurfaces in the Heisenberg group $H_{n}$ with $n$ $\geq$ $2.$ We show that such a hypersurface, if closed, must be rotationally invariant up to a Heisenberg translation. Moreover, we prove that, among others, Pansu spheres are the only such spheres with positive constant sigma-k curvature up to Heisenberg translations.Comment: 28 pages, 6 figure

Umbilicity and characterization of Pansu spheres in the Heisenberg group

For $n\geq 2$ we define a notion of umbilicity for hypersurfaces in the Heisenberg group $H_{n}$. We classify umbilic hypersurfaces in some cases, and prove that Pansu spheres are the only umbilic spheres with positive constant $p$(or horizontal)-mean curvature in $H_{n}$ up to Heisenberg translations.Comment: 32 pages, 2 figures; in Crelle's journal, 201

Study of Effector CD8+ T Cell Interactions with Cortical Neurons in Response to Inflammation in Mouse Brain Slices and Neuronal Cultures

Cytotoxic CD8+ T cells contribute to neuronal damage in inflammatory and degenerative CNS disorders, such as multiple sclerosis (MS). The mechanism of cortical damage associated with CD8+ T cells is not well understood. We developed in vitro cell culture and ex vivo brain slice co-culture models of brain inflammation to study CD8+ T cell–neuron interactions. To induce inflammation, we applied T cell conditioned media, which contains a variety of cytokines, during CD8+ T cell polyclonal activation. Release of IFNγ and TNFα from co-cultures was verified by ELISA, confirming an inflammatory response. We also visualized the physical interactions between CD8+ T cells and cortical neurons using live-cell confocal imaging. The imaging revealed that T cells reduced their migration velocity and changed their migratory patterns under inflammatory conditions. CD8+ T cells increased their dwell time at neuronal soma and dendrites in response to added cytokines. These changes were seen in both the in vitro and ex vivo models. The results confirm that these in vitro and ex vivo models provide promising platforms for the study of the molecular details of neuron–immune cell interactions under inflammatory conditions, which allow high-resolution live microscopy and are readily amenable to experimental manipulation

THE INTELLECTUAL STRUCTURE OF ELECTRONIC RECORDS MANAGEMENT

A number of countries have launched projects with a particular emphasis on using information technologies (IT) to provide electronic information and services to citizens and businesses. Through various IT, tremendous amount of electronic records in government agencies are created. These records and archives are the basis of knowledge management. Electronic records management (ERM) is a fast growing field throughout the last decades. Theoretical foundations for ERM have remained obscure from the research community. To map the intellectual structure of ERM research, this study identifies the high-impact articles as well as the correlations among these scholar publications. In this study, co-citation, co-word, association rule and cluster analysis techniques are used to investigate the intellectual pillars of the ERM literature. This study exposes researchers to a new way of profiling knowledge networks and their relationships the area of ERM, thereby helping academia and practitioners better understand contemporary studies. The results of the mapping can help identify the research direction of ERM research, provide a valuable tool for researchers to access ERM literature, and acts as an exemplary model for future researches

Threshold-free Selection of Taxonomic Multilabels

In online search or content selection systems, significant computational resources are expended to classify or categorize electronic documents into topics, concepts, or entities. A classifier can process, parse or otherwise analyze the document to assign one or more labels to the document based on the taxonomy. The classifier can generate a score for each of the labels, and provide the labels and the scores to other components or modules for further downstream processing. To keep downstream processes efficient without causing excessive processing of labels, the classifier may filter out the labels to return a subset of labels based on comparing a label’s score with a threshold. However, using a threshold-based technique to filter out labels may not account for the tree structure of the taxonomy, and it may also fail to take into account the likelihood dependencies between all parent nodes and child nodes. The proposed technique solves this by (1) selecting a set of labels returned by the classifier that optimizes certain metrics, such as precision and recall metrics; and (2) using a greedy multi-label selection algorithm that optimizes the precision/recall in step (1). Using these techniques, the system can select a subset of labels to return or provide for further processing

Electrically tunable wettability of liquid crystal/polymer composite films

An electrically tunable wettability in a liquid crystal/polymer composite film is demonstrated, in which liquid crystal molecules are anchored among polymer grains. The tunable wettability of the composite films originates from the reorientation of the anchored liquid-crystal molecules, which is switched by an in-plane electric field with squared pulses of voltages. These liquid crystal/polymer composite films with electrically tunable wettability have potential applications in polarizer-free displays, ink-jet printing, microfluidic devices, and lab-on-a-chip