407 research outputs found
Reasoning with Inconsistencies in Hybrid MKNF Knowledge Bases
This article is concerned with the handling of inconsistencies occurring in the combination of description logics and rules, especially in hybrid MKNF knowledge bases. More precisely, we present a paraconsistent semantics for hybrid MKNF knowledge bases (called para-MKNF knowledge bases) based on four-valued logic as proposed by Belnap. We also reduce this paraconsistent semantics to the stable model semantics via a linear transformation operator, which shows the relationship between the two semantics and indicates that the data complexity in our paradigm is not higher than that of classical reasoning. Moreover, we provide fixpoint operators to compute paraconsistent MKNF models, each suitable to different kinds of rules. At last we present the data complexity of instance checking in different para-MKNF knowledge bases
Almost Periodic Solutions for Wilson-Cowan Type Model with Time-Varying Delays
Wilson-Cowan model of neuronal population with time-varying delays is considered in this paper. Some sufficient conditions for the existence and delay-based exponential stability of a unique almost periodic solution are established. The approaches are based on constructing Lyapunov functionals and the well-known Banach contraction mapping principle. The results are new, easily checkable, and complement existing periodic ones
Predicting genome-wide redundancy using machine learning
<p>Abstract</p> <p>Background</p> <p>Gene duplication can lead to genetic redundancy, which masks the function of mutated genes in genetic analyses. Methods to increase sensitivity in identifying genetic redundancy can improve the efficiency of reverse genetics and lend insights into the evolutionary outcomes of gene duplication. Machine learning techniques are well suited to classifying gene family members into redundant and non-redundant gene pairs in model species where sufficient genetic and genomic data is available, such as <it>Arabidopsis thaliana</it>, the test case used here.</p> <p>Results</p> <p>Machine learning techniques that combine multiple attributes led to a dramatic improvement in predicting genetic redundancy over single trait classifiers alone, such as BLAST E-values or expression correlation. In withholding analysis, one of the methods used here, Support Vector Machines, was two-fold more precise than single attribute classifiers, reaching a level where the majority of redundant calls were correctly labeled. Using this higher confidence in identifying redundancy, machine learning predicts that about half of all genes in <it>Arabidopsis </it>showed the signature of predicted redundancy with at least one but typically less than three other family members. Interestingly, a large proportion of predicted redundant gene pairs were relatively old duplications (e.g., Ks > 1), suggesting that redundancy is stable over long evolutionary periods.</p> <p>Conclusions</p> <p>Machine learning predicts that most genes will have a functionally redundant paralog but will exhibit redundancy with relatively few genes within a family. The predictions and gene pair attributes for <it>Arabidopsis </it>provide a new resource for research in genetics and genome evolution. These techniques can now be applied to other organisms.</p
Resveratrol protects against sepsis induced acute kidney injury in mice by inducing Klotho mediated apoptosis inhibition
Purpose: To investigate the mechanism of resveratrol protection against sepsis-induced acute kidney injury in mice.
Methods: A sepsis-induced acute kidney injury model was established in mice by cecal ligation and puncture (CLP). Sixty healthy male ICR mice were randomly divided into the sham operation (sham) group, sepsis-induced acute kidney injury model (CLP) group, CLP + low-dose (20 mg/kg) resveratrol treatment (CLP + ResL) group, CLP + high-dose (40 mg/kg) resveratrol treatment (CLP + ResH) group and CLP + Klotho (0.01 mg/kg) treatment (CLP + Klotho) group. All mice were administered treatment on the day after surgery and once every 24 h for 3 days. Various serum biochemical parameters and protein expressions were evaluated.
Results: After CLP, the levels of serum creatinine (Scr) and blood urea nitrogen (BUN) increased and the pathology was exacerbated. The protein and mRNA expression levels of Klotho and Bcl-2 decreased, while those of Bax and Caspase-3 increased (p < 0.05). After resveratrol and Klotho protein intervention, Scr and BUN levels recovered, and pathological changes were alleviated. The protein and mRNA expression levels of Klotho and Bcl-2 increased, while those of Bax and Caspase-3 decreased. The conditions of the mice in CLP + ResH group and the CLP + Klotho group improved more significantly than those of the mice in the CLP + ResL group (p < 0.05).
Conclusion: Resveratrol upregulates the expression of endogenous Klotho to exert its antiapoptotic effects, which can protect the kidneys of mice against sepsis-induced acute kidney injury. Thus, the compound has potentials for development for protection against acute kidney injury
Prevalence of the GJB2 IVS1+1G >A mutation in Chinese hearing loss patients with monoallelic pathogenic mutation in the coding region of GJB2
<p>Abstract</p> <p>Background</p> <p>Mutations in the GJB2 gene are the most common cause of nonsyndromic recessive hearing loss in China. In about 6% of Chinese patients with severe to profound sensorineural hearing impairment, only monoallelic <it>GJB2 </it>mutations known to be either recessive or of unclear pathogenicity have been identified. This paper reports the prevalence of the <it>GJB2 </it>IVS1+1G>A mutation in a population of Chinese hearing loss patients with monoallelic pathogenic mutation in the coding region of <it>GJB2</it>.</p> <p>Methods</p> <p>Two hundred and twelve patients, screened from 7133 cases of nonsyndromic hearing loss in China, with monoallelic mutation (mainly frameshift and nonsense mutation) in the coding region of <it>GJB2 </it>were examined for the <it>GJB2 </it>IVS1+1G>A mutation and mutations in the promoter region of this gene. Two hundred and sixty-two nonsyndromic hearing loss patients without <it>GJB2 </it>mutation and 105 controls with normal hearing were also tested for the <it>GJB2 </it>IVS1+1G>A mutation by sequencing.</p> <p>Results</p> <p>Four patients with monoallelic mutation in the coding region of <it>GJB2 </it>were found carrying the <it>GJB2 </it>IVS1+1G>A mutation on the opposite allele. One patient with the <it>GJB2 </it>c.235delC mutation carried one variant, -3175 C>T, in exon 1 of <it>GJB2</it>. Neither <it>GJB2 </it>IVS1+1G>A mutation nor any variant in exon 1 of <it>GJB2 </it>was found in the 262 nonsyndromic hearing loss patients without <it>GJB2 </it>mutation or in the 105 normal hearing controls.</p> <p>Conclusion</p> <p>Testing for the <it>GJB2 </it>IVS 1+1 G to A mutation explained deafness in 1.89% of Chinese <it>GJB2 </it>monoallelic patients, and it should be included in routine testing of patients with <it>GJB2 </it>monoallelic pathogenic mutation.</p
An Ionosphere Specification Technique Based on Data Ingestion Algorithm and Empirical Orthogonal Function Analysis Method
A data ingestion method in reproducing ionospheric electron density and total electron content (TEC) was developed to incorporate TEC products from the Madrigal Database into the NeQuick 2 model. The method is based on retrieving an appropriate global distribution of effective ionization parameter (Az) to drive the NeQuick 2 model, which can be implemented through minimizing the difference between the measured and modeled TEC at each grid in the local timeâmodified dip latitude coordinates. The performance of this Madrigal TECâdrivenâNeQuick 2 result is validated through the comparison with various International Global Navigation Satellite Systems Services global ionospheric maps and ionosonde data. The validation results show that a general accuracy improvement of 30â50% can be achieved after data ingestion. In addition, the empirical orthogonal function (EOF) analysis technique is used to construct a parameterized timeâvarying global Az model. The quick convergence of EOF decomposition makes it possible to use the first six EOF series to represent over 90% of the total variances. The intrinsic diurnal variation and spatial distribution in the original data set can be well reflected by the constructed EOF base functions. The associated EOF coefficients can be expressed as a set of linear functions of F10.7 and Ap indices, combined with a series of trigonometric functions with annual/seasonal variation components. The NeQuick TEC driven by EOFâmodeled Az shows 10â15% improvement in accuracy over the standard ionosphere correction algorithm in the Galileo navigation system. These preliminary results demonstrate the effectiveness of the combined data ingestion and EOF modeling technique in improving the specifications of ionospheric density variations.Key PointsThe Madrigal TEC data are ingested into the NeQuick 2 model through deriving an effective ionization parameter (Az)The Empirical Orthogonal Function (EOF) analysis technique is used to construct a parameterized timeâvarying Az model to make a predictionThe TEC data ingestion and EOF modeling are effective in bringing certain systematic improvement of ionosphere nowâcast/forecastPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146373/1/swe20760_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146373/2/swe20760.pd
Trait Mindfulness Is Associated With the Self-Similarity of Heart Rate Variability
Previous studies have linked trait mindfulness with better self-regulation and adaptation. Heart rate variability (HRV) is a good physiological indicator of the capacity for self-regulation and adaptation. The present study explored the relationship between trait mindfulness and HRV from the viewpoint of crosstalking between different HRV parameter pairs, which would reflect the dynamic interactions between each pair of HRV parameters in different processes. We measured the trait mindfulness of seventy-four undergraduate students and recorded nine HRV parameters during the following four consecutive experimental phases: (1) calming phase, (2) mental arithmetic task phase, (3) recovery phase, and (4) mindfulness practice phase. The relationship between trait mindfulness and HRV was explored at the following three levels: (1) the absolute level, i.e., HRV parameters in four different states, (2) the difference-change level, i.e., differences in HRV parameters between different states, and (3) the crosstalking level, i.e., self-similarity of crosstalking HRV parameter pairs. The results supported the following hypothesis: trait mindfulness, as measured by the Mindful Attention Awareness Scale (MAAS), was significantly and positively correlated with the self-similarity of crosstalking HRV parameter pairs but was not significantly correlated with the HRV parameters at the difference-change and absolute levels. These findings indicate that as trait mindfulness increases, the ability to maintain ANS function homeostasis improves.HIGHLIGHTS-Trait mindfulness is associated with better self-regulation and adaptation.-Heart rate variability (HRV) is a good physiological indicator of the capacity for self-regulation and adaptation.-Trait mindfulness is significantly correlated with self-similarity of crosstalking HRV parameter pairs but not with the HRV parameters at the difference-change or absolute levels
Extremely discrepant mutation spectrum of SLC26A4 between Chinese patients with isolated Mondini deformity and enlarged vestibular aqueduct
<p>Abstract</p> <p>Background</p> <p>Mutations in <it>SLC26A4 </it>cause Pendred syndrome (hearing loss with goiter) or DFNB4 (non-syndromic hearing loss with inner ear malformation, such as enlarged vestibular aqueduct or Mondini deformity). The relationship between mutations in <it>SLC26A4 </it>and Mondini deformity without enlarged vestibular aqueduct has not been studied in any Chinese deaf population. The purpose of this study was to assess whether mutations in the <it>SLC26A4 </it>gene cause Mondini deformity without an enlarged vestibular aqueduct (isolated Mondini deformity) in a Chinese population.</p> <p>Methods</p> <p>In total, 144 patients with sensorineural hearing loss were included and subjected to high-resolution temporal bone CT. Among them, 28 patients with isolated Mondini dysplasia (MD group), 50 patients with enlarged vestibular aqueduct with Mondini dysplasia (EVA with MD group), 50 patients with enlarged vestibular aqueduct without Mondini dysplasia (EVA group), and 16 patients with other types of inner ear malformations (IEM group) were identified. The coding exons of <it>SLC26A4 </it>were analyzed in all subjects.</p> <p>Results</p> <p>DNA sequence analysis of <it>SLC26A4 </it>was performed in all 144 patients. In the different groups, the detection rate of the <it>SLC26A4 </it>mutation differed. In the isolated MD group, only one single allelic mutation in <it>SLC26A4 </it>was found in one patient (1/28, 3.6%). In the EVA with MD group, biallelic and monoallelic <it>SLC26A4 </it>mutations were identified in 46 patients (46/50, 92.0%) and three patients (3/50, 6.0%), respectively. Also, in the EVA group, biallelic and monoallelic <it>SLC26A4 </it>mutations were identified in 46 patients (46/50, 92.0%) and three patients (3/50, 6.0%), respectively. These percentages were identical to those in the EVA plus MD group. Only two patients carried monoallelic mutations of the <it>SLC26A4 </it>gene in the IEM group (2/16, 12.5%). There were significant differences in the frequency of <it>SLC26A4 </it>mutation among the groups (P < 0.001). The detection rate of <it>SLC26A4 </it>mutation in the isolated MD group was significantly lower than in the EVA group (with or without MD; P < 0.001), and there was no significant difference in the detection rate of <it>SLC26A4 </it>between the MD group and IEM group (P > 0.5).</p> <p>Conclusion</p> <p>Although mutations in the <it>SLC26A4 </it>gene were frequently found in Chinese EVA patients with and without MD, there was no evidence to show a relationship between isolated MD and the <it>SLC26A4 </it>gene in the Chinese population examined. Hearing impairment in patients with isolated MD may be caused by factors other than mutations in the <it>SLC26A4 </it>gene.</p
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