Identifying Recent Behavioral Data Length in Mobile Phone Log

Mobile phone log data (e.g., phone call log) is not static as it is progressively added to day-by-day according to individ- ual's diverse behaviors with mobile phones. Since human behavior changes over time, the most recent pattern is more interesting and significant than older ones for predicting in- dividual's behavior. The goal of this poster paper is to iden- tify the recent behavioral data length dynamically from the entire phone log for recency-based behavior modeling. To the best of our knowledge, this is the first dynamic recent log-based study that takes into account individual's recent behavioral patterns for modeling their phone call behaviors.Comment: 14th EAI International Conference on Mobile and Ubiquitous Systems: Computing, Networking and Services (MobiQuitous 2017), Melbourne, Australi

Heterogeneous biomedical database integration using a hybrid strategy: a p53 cancer research database.

Complex problems in life science research give rise to multidisciplinary collaboration, and hence, to the need for heterogeneous database integration. The tumor suppressor p53 is mutated in close to 50% of human cancers, and a small drug-like molecule with the ability to restore native function to cancerous p53 mutants is a long-held medical goal of cancer treatment. The Cancer Research DataBase (CRDB) was designed in support of a project to find such small molecules. As a cancer informatics project, the CRDB involved small molecule data, computational docking results, functional assays, and protein structure data. As an example of the hybrid strategy for data integration, it combined the mediation and data warehousing approaches. This paper uses the CRDB to illustrate the hybrid strategy as a viable approach to heterogeneous data integration in biomedicine, and provides a design method for those considering similar systems. More efficient data sharing implies increased productivity, and, hopefully, improved chances of success in cancer research. (Code and database schemas are freely downloadable, http://www.igb.uci.edu/research/research.html.)

Reconstruction of atrial ectopic focal and Re-entrant excitations from body surface potentials. Insights from 3D virtual human atria and torso

Non-invasive electrocardiographic imaging has been seen as a painless and economic method to map the electrical functions of the heart. However, it is still a great challenge to obtain accurate reconstruction of cardiac electrical activity from body surface potentials (BSP) due to the ill-posed behaviour of the cardiac inverse-problem. Though some advances have been made in solving the inverse-problem, few studies have been conducted for the atria, which have dramatic differences to the ventricles in their anatomical structures and electrophysiological properties. It is unclear either how the spatial resolution of electrodes on the BSP and rapid excitation rates of atrial activation during atrial fibrillation affect the accuracy of the inverse-problem. In this study, we used a biophysically detailed model of the human atria and torso to investigate effects of multi-lead ECG on the accuracy of reconstructed atrial excitation pattern on the epicardiac surface during the time courses of atrial fibrillation induced by electrical remodelling. It was shown that the solution of the atrial inverse-problem was dependent on the spatial resolution of electrodes on the body surface. The solution was also influenced by the morphology of the AP, rate and types of atrial excitation as well as the implantation of variant orders of the Tikhonov regularization method

IrSr_2Sm_{1.15}Ce_{0.85}Cu_{2.175}O_{10}: A Novel Reentrant Spin-Glass Material

A new iridium containing layered cuprate material, IrSr_2Sm_{1.15}Ce_{0.85}Cu_{2.175}O_{10, has been synthesized by conventional ambient-pressure solid-state techniques. The material's structure has been fully characterized by Rietveld refinement of high resolution synchrotron X-ray diffraction data; tilts and rotations of the IrO_6 octahedra are observed as a result of a bond mismatch between in-plane Ir-O and Cu-O bond lengths. DC-susceptibility measurements evidence a complex set of magnetic transitions upon cooling that are characteristic of a reentrant spin-glass ground-state. The glassy character of the lowest temperature, Tg=10 K, transition is further confirmed by AC-susceptibility measurements, showing a characteristic frequency dependence that can be well fitted by the Vogel-Fulcher law and yields a value of \Delta_(T_f)/[T_f \Delta log({\omega})] =0.015(1), typical of dilute magnetic systems. Electronic transport measurements show the material to be semiconducting at all temperatures with no transition to a superconducting state. Negative magnetoresistance is observed when the material is cooled below 25 K, and the magnitude of this magnetoresistance is seen to increase upon cooling to a value of MR = -9 % at 8 K

The effect of bioenergetic impairment of cytosolic processes in spatio-temporal Ca²⁺ dynamics in a three-dimensional cardiomyocyte model

The heart consumes large amounts of energy with each beat. Mitochondria are the source of over 95% of this energy in the form of ATP and rely on increased Ca²⁺ uptake to stimulate production in times of increased work. Ca²⁺ uptake into the mitochondria primarily occurs within microdomains. Structural remodeling associated with heart failure may disrupt these microdomains leading to impaired mitochondrial Ca²⁺ uptake and energetic impairment. To investigate the effect of structural changes on single cell behavior, a model describing mitochondrial dynamics and energetics production is modified and incorporated into a recently developed three-dimensional model of spatio-temporal calcium handling, which preserves microdomain structure and incorporates stochastic processes in Ca²⁺ handling protein kinetics. Modifications to the mitochondria model included a reformulation of mitochondrial Ca²⁺ uniporter uptake, making it suitable for concentrations in microdomains. With this model we demonstrate the importance of an ordered structure within the cell for normal function. Changes in the arrangement of mitochondria can have a pronounced effect on intracellular Ca²⁺ dynamics through their energetic regulation of SERCA, leading to spatially heterogeneous sarcoplasmic reticulum uptake and loading

Structural and spin-glass properties of single crystal JeffJ_{eff} = 1/2 pyrochlore antiferromagnet NaCdCo2_2F7_7 : correlating TfT_f with magnetic-bond-disorder

Weak bond disorder disrupts the expected spin-liquid ground-state of the ideal $S$ = 1/2 Heisenberg pyrochlore antiferromagnet. Here we introduce a single crystal study of the structural and magnetic properties of the bond-disordered pyrochlore NaCdCo$_2$F$_7$. The magnetic susceptibility appears isotropic, with a large negative Curie-Weiss temperature ($\theta_{CW}$ = -108(1) K), however no magnetic order is observed on cooling until a spin-glass transition at $T_f$ = 4.0 K. AC-susceptibility measurements show a frequency-dependent shift of the associated cusp in $\chi$ at $T_f$, that can be fitted well by the empirical Vogel-Fulcher law. The magnetic moment of $\mu_{eff}$ = 5.4(1) $\mu_{B}$/Co$^{2+}$ indicates a significant orbital contribution and heat capacity measurements show that down to 1.8 K, well below $T_f$, only $S_{mag}$ ~2/3 Rln(2) of the magnetic entropy is recovered, suggestive of residual continued dynamics. Structural and magnetism comparisons are made with the other known members of the Na$A$Co$_2$F$_7$ family ($A$ = Ca$^{2+}$, Sr$^{2+}$), confirming the expected relationship between spin-glass freezing temperature, and extent of magnetic bond disorder brought about by the size mismatch between A-site ions