9,832 research outputs found
Building a family ontology to meet consistency criteria
Semantic web is an extension of the current web in which the existing information on
the web are organized and encoded more meaningfully using ontology language, thus
enabling effective communication among machines and humans. Ontology is the
backbone of the semantic web that contributes to knowledge sharing among intended
parties over distributed systems around the world. In the past few years, semantic web
has been widely accepted by a variety of fields for better knowledge representation,
communication, sharing and reasoning on the web. Now, there are existing genealogical
ontologies proposed by different groups of researchers once semantic web has emerged
as third generation of the web. However, existing ontologies still lack certain important
concepts and properties to support the domain of family relations. This may lead to the
inability of the ontology to deliver full potential of exchanging family history
information among all interested parties. Moreover, existing ontologies do not employ
the full potential of SWRL rules to reason the individuals within the ontology. The main
aim of this research is to build a new Family Ontology which obeys the consistency
criteria. Consistency checking ensures there are no contradictory concepts found within
the resulting ontology. The consistency of Family Ontology will be evaluated using
FACT++, HermiT and Pellet reasoners. By augmenting the additional axioms and
testing the resulting ontology thoroughly using reasoner tools, the proposed Family
Ontology is expected to achieve a consistency of 100%.This research is meaningful and
significant to all humans since everyone has his or her own unique family history. The
proposed ontology also facilitates effective and efficient communication among all
intended parties since shared vocabularies and standards are employed by the proposed
ontology
On the Throughput of Channels that Wear Out
This work investigates the fundamental limits of communication over a noisy
discrete memoryless channel that wears out, in the sense of signal-dependent
catastrophic failure. In particular, we consider a channel that starts as a
memoryless binary-input channel and when the number of transmitted ones causes
a sufficient amount of damage, the channel ceases to convey signals. Constant
composition codes are adopted to obtain an achievability bound and the
left-concave right-convex inequality is then refined to obtain a converse bound
on the log-volume throughput for channels that wear out. Since infinite
blocklength codes will always wear out the channel for any finite threshold of
failure and therefore cannot convey information at positive rates, we analyze
the performance of finite blocklength codes to determine the maximum expected
transmission volume at a given level of average error probability. We show that
this maximization problem has a recursive form and can be solved by dynamic
programming. Numerical results demonstrate that a sequence of block codes is
preferred to a single block code for streaming sources.Comment: 23 pages, 1 table, 11 figures, submitted to IEEE Transactions on
Communication
Transient analysis of M/M/1 queuing theory: an overview
Queuing is a common phenomenon in our daily life. Mathematical study on waiting line or queues is called queuing theory. Generally, queuing theory has been used extensively by service industry in order to optimize the service effectiveness and improve the customer satisfaction since it helps an organization to understand how a system operates while reviewing the efficiency of the system. Most of queuing theory deals with system performance in steady-state condition. That is, most queuing models assume that the system has been operating with the same arrival rate, service rate and other characteristics for a sufficiently long time that the probabilistic behavior of performance measures such as queue length is independent of initial condition. However, in many situations, the parameters defining the queuing system may vary over time. Under such circumstances, it is most unlikely that such systems are in equilibrium. This paper reviews the transient behavior (no assumption of statistical equilibrium) of the queuing model. The aim is to provide sufficient information to analysts who are interested in studying queuing theory with this special characteristic
Dissecting the genetic components of a quantitative trait locus for blood pressure and renal pathology on rat chromosome 3
Background: We have previously confirmed the importance of rat chromosome 3 (RNO3) genetic loci on blood pressure elevation, pulse pressure (PP) variability and renal pathology during salt challenge in the stroke-prone spontaneously hypertensive (SHRSP) rat. The aims of this study were to generate a panel of RNO3 congenic sub-strains to genetically dissect the implicated loci and identify positional candidate genes by microarray expression profiling and analysis of next-generation sequencing data.
Method and results: A panel of congenic sub-strains were generated containing Wistar-Kyoto (WKY)-introgressed segments of varying size on the SHRSP genetic background, focused within the first 50 Mbp of RNO3. Haemodynamic profiling during salt challenge demonstrated significantly reduced systolic blood pressure, diastolic blood pressure and PP variability in SP.WKYGla3a, SP.WKYGla3c, SP.WKYGla3d and SP.WKYGla3e sub-strains. Only SBP and DBP were significantly reduced during salt challenge in SP.WKYGla3b and SP.WKYGla3f sub-strains, whereas SP.WKYGla3g rats did not differ in haemodynamic response to SHRSP. Those sub-strains demonstrating significantly reduced PP variability during salt challenge also demonstrated significantly reduced renal pathology and proteinuria. Microarray expression profiling prioritized two candidate genes for blood pressure regulation (Dnm1, Tor1b), localized within the common congenic interval shared by SP.WKYGla3d and SP.WKYGla3f strains, and one candidate gene for salt-induced PP variability and renal pathology (Rabgap1), located within the region unique to the SP.WKYGla3d strain. Comparison of next-generation sequencing data identified variants within additional positional genes that are likely to affect protein function.
Conclusion: This study has identified distinct intervals on RNO3-containing genes that may be important for blood pressure regulation and renal pathology during salt challenge
Reconstituted high-density lipoproteins promote wound repair and blood flow recovery in response to ischemia in aged mice
Background: The average population age is increasing and the incidence of age-related vascular complications is rising in parallel. Impaired wound healing and disordered ischemia-mediated angiogenesis are key contributors to age-impaired vascular complications that can lead to amputation. High-density lipoproteins (HDL) have vasculo-protective properties and augment ischemia-driven angiogenesis in young animals. We aimed to determine the effect of reconstituted HDL (rHDL) on aged mice in a murine wound healing model and the hindlimb ischemia (HLI) model. Methods: Murine wound healing model—24-month-old aged mice received topical application of rHDL (50 μg/wound/ day) or PBS (vehicle control) for 10 days following wounding. Murine HLI model—Femoral artery ligation was performed on 24-month-old mice. Mice received rHDL (40 mg/kg) or PBS, intravenously, on alternate days, 1 week pre-surgery and up to 21 days post ligation. For both models, blood flow perfusion was determined using laser Doppler perfusion imaging. Mice were sacrificed at 10 (wound healing) or 21 (HLI) days post-surgery and tissues were collected for histological and gene analyses. Results: Daily topical application of rHDL increased the rate of wound closure by Day 7 post-wounding (25 %, p < 0.05). Wound blood perfusion, a marker of angiogenesis, was elevated in rHDL treated wounds (Days 4–10 by 22–25 %, p < 0. 05). In addition, rHDL increased wound capillary density by 52.6 %. In the HLI model, rHDL infusions augmented blood flow recovery in ischemic limbs (Day 18 by 50 % and Day 21 by 88 %, p < 0.05) and prevented tissue necrosis and toe loss. Assessment of capillary density in ischemic hindlimb sections found a 90 % increase in rHDL infused animals. In vitro studies in fibroblasts isolated from aged mice found that incubation with rHDL was able to significantly increase the key pro-angiogenic mediator vascular endothelial growth factor (VEGF) protein (25 %, p < 0.05). Conclusion: rHDL can promote wound healing and wound angiogenesis, and blood flow recovery in response to ischemia in aged mice. Mechanistically, this is likely to be via an increase in VEGF. This highlights a potential role for HDL in the therapeutic modulation of age-impaired vascular complications
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