The Single-Uniprior Index-Coding Problem: The Single-Sender Case and The Multi-Sender Extension

Index coding studies multiterminal source-coding problems where a set of receivers are required to decode multiple (possibly different) messages from a common broadcast, and they each know some messages a priori. In this paper, at the receiver end, we consider a special setting where each receiver knows only one message a priori, and each message is known to only one receiver. At the broadcasting end, we consider a generalized setting where there could be multiple senders, and each sender knows a subset of the messages. The senders collaborate to transmit an index code. This work looks at minimizing the number of total coded bits the senders are required to transmit. When there is only one sender, we propose a pruning algorithm to find a lower bound on the optimal (i.e., the shortest) index codelength, and show that it is achievable by linear index codes. When there are two or more senders, we propose an appending technique to be used in conjunction with the pruning technique to give a lower bound on the optimal index codelength; we also derive an upper bound based on cyclic codes. While the two bounds do not match in general, for the special case where no two distinct senders know any message in common, the bounds match, giving the optimal index codelength. The results are expressed in terms of strongly connected components in directed graphs that represent the index-coding problems.Comment: Author final manuscrip

The Multi-Sender Multicast Index Coding

We focus on the following instance of an index coding problem, where a set of receivers are required to decode multiple messages, whilst each knows one of the messages a priori. In particular, here we consider a generalized setting where they are multiple senders, each sender only knows a subset of messages, and all senders are required to collectively transmit the index code. For a single sender, Ong and Ho (ICC, 2012) have established the optimal index codelength, where the lower bound was obtained using a pruning algorithm. In this paper, the pruning algorithm is simplified, and used in conjunction with an appending technique to give a lower bound to the multi-sender case. An upper bound is derived based on network coding. While the two bounds do not match in general, for the special case where no two senders know any message bit in common, the bounds match, giving the optimal index codelength. The results are derived based on graph theory, and are expressed in terms of strongly connected components.Comment: This is an extended version of the same-titled paper accepted and to be presented at the IEEE International Symposium on Information Theory (ISIT), Istanbul, in July 201

ADVANCED OXIDATION PROCESS FOR TREATMENT OF AQUEOUS SOLUTION CONTAINING POLYCYCLIC AROMATIC HYDROCARBONS (PAHS)

Polycyclic Aromatic Hydrocarbons (PAHs) is a type of persistent organic pollutant that categorized by United States Environmental Protection Agency (USEPA) as toxic, carcinogenic and mutagenic. The presence of PAHs in aquatic environment poses harmful effect to the aquatic life as well as the human beings due to the bioaccumulation in the food chain that can lead to cancer and birth defect. The advanced oxidation process- UV/H2O2 system had been adopted and carried out for the treatment of PAHs in the aqueous solution by many researchers. However, the optimization of the process for treatment PAHs had not yet been reported. In this study, the performance of the process was assessed by carrying out preliminary experiments and optimized by response surface methodology (RSM). The synthetic water sample was prepared by diluting the 16 PAHs standard solution mix in deionized water. The preliminary experiments were carried out to determine the range of the operational variables- H2O2 concentration, pH and reaction time. The maximum COD removal achieved in preliminary experiment was 71.5% under the operating condition of 1mM H2O2 concentration, pH of 3.5 and 90 minutes reaction time. The Design Expert Software was utilized for the optimization of the UV/H2O2 system by RSM based on five-level central composite design (CCD). The ranges for RSM were 1-3 mM for H2O2 concentration, 2-5 for pH and 30-90 minutes for reaction time. The quadratic equation fitted the model well and was found to be significant and adequate by ANOVA analysis and diagnostics plots. The optimum operating condition which achieved COD removal efficiency of 79.78% were H2O2 concentration of 1mM, pH of 3.5 and reaction time of 90 minutes. The experimental data and model prediction agreed well with error less than 3%. The PAHs removal efficiency was 84.28%. The study revealed that the UV/H2O2 process is effective for treatment of PAHs in aqueous solution and the process can be optimized by RSM

The orientation of the nuclear obscurer of the AGNs

We examine the distribution of axis ratios of a large sample of disk galaxies hosting type 2 AGNs selected from the Sloan Digital Sky Survey and compare it with a well-defined control sample of non-active galaxies. We find them significantly different, where the type 2 AGNs show both an excess of edge-on objects and deficit of round objects. This systematical bias can not be explained by a nuclear obscurer oriented randomly with respect to the stellar disk. However, a nuclear obscurer coplanar with the stellar disk also does not fit the data very well. By assuming that the nuclear obscurer having an opening angle of ~60 degree, we find the observed axis ratio distribution can be nicely reproduced by a mean tilt angle of ~30 degree between the nuclear obscurer and the stellar disk.Comment: 5 pages, 3 figures, to appear in ApJ

Bioluminescence in vivo imaging of autoimmune encephalomyelitis predicts disease

<p>Abstract</p> <p>Background</p> <p>Experimental autoimmune encephalomyelitis is a widely used animal model to understand not only multiple sclerosis but also basic principles of immunity. The disease is scored typically by observing signs of paralysis, which do not always correspond with pathological changes.</p> <p>Methods</p> <p>Experimental autoimmune encephalomyelitis was induced in transgenic mice expressing an injury responsive luciferase reporter in astrocytes (GFAP-luc). Bioluminescence in the brain and spinal cord was measured non-invasively in living mice. Mice were sacrificed at different time points to evaluate clinical and pathological changes. The correlation between bioluminescence and clinical and pathological EAE was statistically analyzed by Pearson correlation analysis.</p> <p>Results</p> <p>Bioluminescence from the brain and spinal cord correlates strongly with severity of clinical disease and a number of pathological changes in the brain in EAE. Bioluminescence at early time points also predicts severity of disease.</p> <p>Conclusion</p> <p>These results highlight the potential use of bioluminescence imaging to monitor neuroinflammation for rapid drug screening and immunological studies in EAE and suggest that similar approaches could be applied to other animal models of autoimmune and inflammatory disorders.</p

X-ray absorption and rapid variability of the dwarf Seyfert nucleus of NGC4395

We report the detection of an absorbed central X-ray source and its strong, rapid variability in NGC4395, the least luminous Seyfert nucleus known. The X-ray source exhibits a number of flares with factors of 3-4 flux changes during a half day ASCA observation. Such X-ray variability is in constrast to the behaviour of other low luminosity active galaxies. It provides further support for an accreting black hole model rather than an extreme stellar process in accounting for the nuclear activity of NGC4395. The soft X-ray emission below 3 keV is strongly attenuated by absorption. The energy spectrum in this absorption band shows a dramatic change in response to the variation in continuum luminosity. A variable warm absorber appears to be an explanation for the spectral change. The absorption-corrected 2-10 keV luminosity is 4e39 erg/s for a source distance of 2.6 Mpc, and at 1 keV is one order of magnitude above previous ROSAT estimates. Our X-ray results infer the nuclear source of NGC4395 to be a scaled-down version of higher luminosity Seyfert nuclei, with an intermediate mass (10^4-10^5 Msun) black hole, unlike the nearby low luminosity active galaxies in which underfed massive black holes are suspected to reside.Comment: 12 pages, accepted for publication in MNRA

Qualitative study of loneliness in a senior housing community: the importance of wisdom and other coping strategies.

ObjectiveOlder adults are at a high risk for loneliness, which impacts their health, well-being, and longevity. While related to social isolation, loneliness is a distinct, internally experienced, distressing feeling. The present qualitative study sought to identify characteristics of loneliness in older adults living independently within a senior housing community, which is typically designed to reduce social isolation.MethodSemi-structured qualitative interviews regarding the experience of loneliness, risk factors, and ways to combat it were conducted with 30 older adults, ages 65-92 years. The interviews were audiotaped, transcribed, and coded using a grounded theory analytic approach based on coding, consensus, co-occurrence, and comparison.ResultsThree main themes with multiple subthemes are described: (A) Risk and Protective factors for loneliness: age-associated losses, lack of social skills or abilities, and protective personality traits; (B) Experience of loneliness: Sadness and lack of meaning as well as Lack of motivation; and (C) Coping strategies to prevent or overcome loneliness: acceptance of aging, compassion, seeking companionship, and environment enables socialization.DiscussionDespite living within a communal setting designed to reduce social isolation, many older adults described feeling lonely in stark negative terms, attributing it to aging-associated losses or lack of social skills and abilities. However, interviewees also reported positive personal qualities and actions to prevent or cope with loneliness, several of which mirrored specific components of wisdom. The results support the reported inverse relationship between loneliness and wisdom and suggest a potential role for wisdom-enhancing interventions to reduce and prevent loneliness in older populations

Induction of Paralysis and Visual System Injury in Mice by T Cells Specific for Neuromyelitis Optica Autoantigen Aquaporin-4.

While it is recognized that aquaporin-4 (AQP4)-specific T cells and antibodies participate in the pathogenesis of neuromyelitis optica (NMO), a human central nervous system (CNS) autoimmune demyelinating disease, creation of an AQP4-targeted model with both clinical and histologic manifestations of CNS autoimmunity has proven challenging. Immunization of wild-type (WT) mice with AQP4 peptides elicited T cell proliferation, although those T cells could not transfer disease to naïve recipient mice. Recently, two novel AQP4 T cell epitopes, peptide (p) 135-153 and p201-220, were identified when studying immune responses to AQP4 in AQP4-deficient (AQP4-/-) mice, suggesting T cell reactivity to these epitopes is normally controlled by thymic negative selection. AQP4-/- Th17 polarized T cells primed to either p135-153 or p201-220 induced paralysis in recipient WT mice, that was associated with predominantly leptomeningeal inflammation of the spinal cord and optic nerves. Inflammation surrounding optic nerves and involvement of the inner retinal layers (IRL) were manifested by changes in serial optical coherence tomography (OCT). Here, we illustrate the approaches used to create this new in vivo model of AQP4-targeted CNS autoimmunity (ATCA), which can now be employed to study mechanisms that permit development of pathogenic AQP4-specific T cells and how they may cooperate with B cells in NMO pathogenesis

Effect of audible and visual reminders on adherence in glaucoma patients using a commercially available dosing aid

We studied the effects of audible and visual alarms on adherence with a recommended dosing regimen in the management of glaucoma. Forty-two patients were begun on therapy with the Travatan® Dosing Aid (TDA) and randomly divided into two observation groups – one with visual and audible alarm functions turned on and the other with alarms off. Dosing information was analyzed for mean rates of adherence, missed days, and dosing at the wrong time. Twenty patients were randomized to the TDA alarm on group and 22 to the alarm off group. The rates of adherence were 87.9% and 79.7% (p = 0.02), rates of missed dosing were 7.6% and 14.4% (p = 0.03), and rates of dosing at the incorrect times were 7.1% and 9.8% (p = 0.19), respectively for alarm on versus alarm off groups. In the alarm on group, the adherence rate was significantly higher and proportion of missed dosing was significantly lower. It is still yet to be determined whether there is a relationship between adherence and progression of glaucoma