1,175 research outputs found

    Implementing the Duty Trip Support Application

    Get PDF
    We are in the process of developing an agent and ontology-based Duty Trip Support application. The goal of this paper is to consider issues arising when implementing such a system. In addition to the description of our current implementation, which is also critically analyzed, other possible approaches are considered as well.software agents, agent systems, ontologies, transport objects, agent-non-agent integration.

    A Hybrid Technique for Medical Image Segmentation

    Get PDF
    Medical image segmentation is an essential and challenging aspect in computer-aided diagnosis and also in pattern recognition research. This paper proposes a hybrid method for magnetic resonance (MR) image segmentation. We first remove impulsive noise inherent in MR images by utilizing a vector median filter. Subsequently, Otsu thresholding is used as an initial coarse segmentation method that finds the homogeneous regions of the input image. Finally, an enhanced suppressed fuzzy c-means is used to partition brain MR images into multiple segments, which employs an optimal suppression factor for the perfect clustering in the given data set. To evaluate the robustness of the proposed approach in noisy environment, we add different types of noise and different amount of noise to T1-weighted brain MR images. Experimental results show that the proposed algorithm outperforms other FCM based algorithms in terms of segmentation accuracy for both noise-free and noise-inserted MR images

    Catalpol Modulates Lifespan via DAF-16/FOXO and SKN-1/Nrf2 Activation in

    Get PDF
    Catalpol is an effective component of rehmannia root and known to possess various pharmacological properties. The present study was aimed at investigating the potential effects of catalpol on the lifespan and stress tolerance using C. elegans model system. Herein, catalpol showed potent lifespan extension of wild-type nematode under normal culture condition. In addition, survival rate of catalpol-fed nematodes was significantly elevated compared to untreated control under heat and oxidative stress but not under hyperosmolality conditions. We also found that elevated antioxidant enzyme activities and expressions of stress resistance proteins were attributed to catalpol-mediated increased stress tolerance of nematode. We further investigated whether catalpol’s longevity effect is related to aging-related factors including reproduction, food intake, and growth. Interestingly, catalpol exposure could attenuate pharyngeal pumping rate, indicating that catalpol may induce dietary restriction of nematode. Moreover, locomotory ability of aged nematode was significantly improved by catalpol treatment, while lipofuscin levels were attenuated, suggesting that catalpol may affect age-associated changes of nematode. Our mechanistic studies revealed that mek-1, daf-2, age-1, daf-16, and skn-1 are involved in catalpol-mediated longevity. These results indicate that catalpol extends lifespan and increases stress tolerance of C. elegans via DAF-16/FOXO and SKN-1/Nrf activation dependent on insulin/IGF signaling and JNK signaling

    : A Model System for Anti-Cancer Drug Discovery and Therapeutic Target Identification

    Get PDF
    The nematode Caenorhabditis elegans (C. elegans) offers a unique opportunity for biological and basic medical researches due to its genetic tractability and well-defined developmental lineage. It also provides an exceptional model for genetic, molecular, and cellular analysis of human disease-related genes. Recently, C. elegans has been used as an ideal model for the identification and functional analysis of drugs (or small-molecules) in vivo. In this review, we describe conserved oncogenic signaling pathways (Wnt, Notch, and Ras) and their potential roles in the development of cancer stem cells. During C. elegans germline development, these signaling pathways regulate multiple cellular processes such as germline stem cell niche specification, germline stem cell maintenance, and germ cell fate specification. Therefore, the aberrant regulations of these signaling pathways can cause either loss of germline stem cells or overproliferation of a specific cell type, resulting in sterility. This sterility phenotype allows us to identify drugs that can modulate the oncogenic signaling pathways directly or indirectly through a high-throughput screening. Current in vivo or in vitro screening methods are largely focused on the specific core signaling components. However, this phenotype-based screening will identify drugs that possibly target upstream or downstream of core signaling pathways as well as exclude toxic effects. Although phenotype-based drug screening is ideal, the identification of drug targets is a major challenge. We here introduce a new technique, called Drug Affinity Responsive Target Stability (DARTS). This innovative method is able to identify the target of the identified drug. Importantly, signaling pathways and their regulators in C. elegans are highly conserved in most vertebrates, including humans. Therefore, C. elegans will provide a great opportunity to identify therapeutic drugs and their targets, as well as to understand mechanisms underlying the formation of cancer

    An Effective Approach to Improving Low-Cost GPS Positioning Accuracy in Real-Time Navigation

    Get PDF
    Positioning accuracy is a challenging issue for location-based applications using a low-cost global positioning system (GPS). This paper presents an effective approach to improving the positioning accuracy of a low-cost GPS receiver for real-time navigation. The proposed method precisely estimates position by combining vehicle movement direction, velocity averaging, and distance between waypoints using coordinate data (latitude, longitude, time, and velocity) of the GPS receiver. The previously estimated precious reference point, coordinate translation, and invalid data check also improve accuracy. In order to evaluate the performance of the proposed method, we conducted an experiment using a GARMIN GPS 19xHVS receiver attached to a car and used Google Maps to plot the processed data. The proposed method achieved improvement of 4–10 meters in several experiments. In addition, we compared the proposed approach with two other state-of-the-art methods: recursive averaging and ARMA interpolation. The experimental results show that the proposed approach outperforms other state-of-the-art methods in terms of positioning accuracy

    The French Aging Males' Symptoms (AMS) scale: Methodological review

    Get PDF
    BACKGROUND: The AMS is an internationally used health-related quality of life (HRQoL) scale. The aim of this paper is to provide evidence that the French AMS scale measures HRQoL are as valid as other language versions. We also intend to show whether the application of AMS is really limited to aging males only or not. More generally, we like to demonstrate that the AMS scale is a relevant, validated, sensitive instrument to measure HRQoL and change of symptoms in France. METHODS: We performed a representative survey in France to get data AMS scale data. The French data were compared with existing data from other European countries. Only community-based data were used for this comparison. RESULTS AND DISCUSSION: Reliability (here consistency, Cronbach' s alpha) was found to be good and almost identical with other countries. Validity: the internal structure of the AMS (factorial analysis) was sufficiently comparable with the comparison group of other countries in Europe to conclude that the scale really measures the same phenomenon. The sub-scores and total score correlations (Pearson) were high (r = 0.8–0.9) but only somewhat lower among the sub-scales (r = 0.5–0.7). This suggests that the domains are correlated. The comparison of the French AMS with the generic quality-of-life scale SF-12 showed a good correlation (Pearson r = 0.48 – 0.51) as reported from other countries. We observed also a good correlation between the AMS scale and the depression scale HAD (Pearson r = 0.62). The analysis of the AMS structure across age groups showed sufficient similarity to suggest that the AMS is also useful for younger age groups. CONCLUSION: The French AMS scale is a standardized HRQoL scale with good psychometric characteristics (reliability, validity) as shown for other international versions. We suggest that the AMS scale could be also used in age groups under 40 years to measure and compare HRQoL in males. Since the application of the AMS in younger age was not investigated before, confirmation in future studies is needed

    A hybrid feature pool-based emotional stress state detection algorithm using EEG signals.

    Get PDF
    Human stress analysis using electroencephalogram (EEG) signals requires a detailed and domain‐specific information pool to develop an effective machine learning model. In this study, a multi‐domain hybrid feature pool is designed to identify most of the important information from the signal. The hybrid feature pool contains features from two types of analysis: (a) statistical parametric analysis from the time domain, and (b) wavelet‐based bandwidth specific feature analysis from the time‐frequency domain. Then, a wrapper‐based feature selector, Boruta, is applied for ranking all the relevant features from that feature pool instead of considering only the nonredundant features. Finally, the k‐nearest neighbor (k‐NN) algorithm is used for final classification. The proposed model yields an overall accuracy of 73.38% for the total considered dataset. To validate the performance of the proposed model and highlight the necessity of designing a hybrid feature pool, the model was compared to non‐linear dimensionality reduction techniques, as well as those without feature ranking

    Triclosan: An Update on Biochemical and Molecular Mechanisms

    Get PDF
    Triclosan (TCS) is a synthetic, chlorinated phenolic antimicrobial agent commonly used in commercial and healthcare products. Items made with TCS include soaps, deodorants, shampoos, cosmetics, textiles, plastics, surgical sutures, and prosthetics. A wealth of information obtained from in vitro and in vivo studies has demonstrated the therapeutic effects of TCS, particularly against inflammatory skin conditions. Nevertheless, extensive investigations on the molecular aspects of TCS action have identified numerous adversaries associated with the disinfectant including oxidative injury and influence of physiological lifespan and longevity. This review presents a summary of the biochemical alterations pertaining to TCS exposure, with special emphasis on the diverse molecular pathways responsive to TCS that have been elucidated during the present decade
    corecore