50 research outputs found

    A fuzzy logic scheme for real-time routing in wireless sensor networks

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    © 2015 IEEE. Real-time communications is still remain a major research challenge due to the limited energy supply, limited computing power, and limited bandwidth of the wireless links connecting sensor nodes in wireless sensor networks (WSNs). Due to these limitations, sensor nodes are not powerful enough to accommodate the complexity of the real-time WSNs protocol. In real-time WSNs, to increase reliability of data delivery the high hit rate and reduction of packet losses is required. To solve these problems, we proposed a new fuzzy controller based routing algorithm to optimize real-time communication in WSNs. The main objectives of the proposed fuzzy controller are 1) to reduce energy consumption among nodes in order to increase network lifetime, 2) to meet real-time packet deadline, reduce end-to-end delay and packet losses. Furthermore, the proposed scheme adjusting the transmission range of surplus nodes to shortened end-to-end delay. We show through extensive simulation results that our proposed fuzzy algorithm considerably reduces energy consumption and noticeable improved real-time performance in comparison with existing schemes

    Guaranteed lifetime protocol for IoT based wireless sensor networks with multiple constraints

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    © 2020 Elsevier B.V. Over the past two decades, the subject of extension of the lifetime of Wireless Sensor Networks (WSN) based on the Internet of Things (IoT) has been thoroughly investigated by researcher. As WSN, and its new form based on IoT, are increasingly being deployed in time-critical applications, users require certain network lifetime guarantees to satisfy application requirements. Few research efforts in the past have focused on guaranteeing the IoT-based network lifetime. Most such efforts pay little or no attention to other network performance indicators such as sensing coverage and network connectivity. To address this challenge, this work proposes a new centralized approach that analyzes a network\u27s energy consumption to optimize node duty cycles. In the proposed scheme, the sink node periodically assigns an active/sleep role to each node for the next network cycle by coupling the residual energy, total active time, and possible coverage area to guarantee their lifetimes. We show through extensive simulation that the proposed guaranteed lifetime protocol achieves less average end-to-end delay and better packet delivery ratio when compared to its best rival protocols formulated in past research, i.e., the CERACC, A-Mac, and Coverage Preserving protocols

    Expression of M. tuberculosis-induced suppressor of cytokine signaling (SOCS) 1, SOCS3, FoxP3 and secretion of IL-6 associates with differing clinical severity of tuberculosis

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    Background Appropriate immune activation of T cells and macrophages is central for the control of Mycobacterium tuberculosis infections. IFN-γ stimulated responses are lowered in tuberculosis (TB), while expression of Suppressor of Cytokine Signaling (SOCS) molecules – 1 and 3 and CD4+CD25+FoxP3+T regulatory cells is increased. Here we investigated the association of these molecules in regard to clinical severity of TB. Methods Peripheral blood mononuclear cells (PBMCs) were isolated from patients with pulmonary TB (PTB, n = 33), extra-pulmonary TB (ETB, n = 33) and healthy endemic controls (EC, n = 15). Cases were classified as moderately advanced or far advanced PTB, and less severe or severe disseminated ETB. M. tuberculosis -stimulated IFN-γ, SOCS1, SOCS3 and FoxP3 gene expression and secretion of Th1 and Th2 cytokines was measured. Statistical analysis was performed using Mann–Whitney U, Wilcoxon Rank and Kruskal Wallis non-parametric tests. Results In un-stimulated PBMCs, IL-6 (p = 0.018) and IL-10 (p = 0.013) secretion levels were increased in PTB while IL-10 was also increased in ETB (p = 0.003), all in comparison with EC. M. tuberculosis-stimulated IL-6 (p = 0.003) was lowered in ETB as compared with EC. SOCS1 mRNA expression in M. tuberculosis stimulated PBMCs levels in moderately advanced PTB (p = 0.022), far advanced (p = 0.014) PTB, and severe ETB (p = 0.009) were raised as compared with EC. On the other hand, SOCS1 mRNA titers were reduced in less severe ETB, in comparison with severe ETB (p = 0.027) and far advanced PTB (p = 0.016). SOCS3 mRNA accumulation was reduced in far advanced PTB (p = 0.007) and FoxP3 mRNA expression was increased in less severe ETB as compared with EC (p = 0.017). Conclusions The lowered SOCS1 mRNA levels in patients with less severe extra-pulmonary TB as compared to those with more severe ETB and PTB may lead to elevated IFN-γ pathway gene expression in the latter group. As localized ETB has shown to be associated with more effective Th1 immunity and adaptive responses, this suggests a role for SOCS1 in determining disease outcome in extra-pulmonary TB

    Mammographic density does not correlate with Ki-67 expression or cytomorphology in benign breast cells obtained by random periareolar fine needle aspiration from women at high risk for breast cancer

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    BACKGROUND:Ki-67 expression is a possible risk biomarker and is currently being used as a response biomarker in chemoprevention trials. Mammographic breast density is a risk biomarker and is also being used as a response biomarker. We previously showed that Ki-67 expression is higher in specimens of benign breast cells exhibiting cytologic atypia that are obtained by random periareolar fine needle aspiration (RPFNA). It is not known whether there is a correlation between mammographic density and Ki-67 expression in benign breast ductal cells obtained by RPFNA.METHODS:Included in the study were 344 women at high risk for developing breast cancer (based on personal or family history), seen at The University of Kansas Medical Center high-risk breast clinic, who underwent RPFNA with cytomorphology and Ki-67 assessment plus a mammogram. Mammographic breast density was assessed using the Cumulus program. Categorical variables were analyzed by ?2 test, and continuous variables were analyzed by nonparametric test and linear regression.RESULTS:Forty-seven per cent of women were premenopausal and 53% were postmenopausal. The median age was 48 years, median 5-year Gail Risk was 2.2%, and median Ki-67 was 1.9%. The median mammographic breast density was 37%. Ki-67 expression increased with cytologic abnormality (atypia versus no atypia; P = 0.001) and younger age (=50 years versus >50 years; P = 0.001). Mammographic density was higher in premenopausal women (P = 0.001), those with lower body mass index (P < 0.001), and those with lower 5-year Gail risk (P = 0.001). Mammographic density exhibited no correlation with Ki-67 expression or cytomorphology.CONCLUSION:Given the lack of correlation of mammographic breast density with either cytomorphology or Ki-67 expression in RPFNA specimens, mammographic density and Ki-67 expression should be considered as potentially complementary response biomarkers in breast cancer chemoprevention trials

    An operative case of hepatic pseudolymphoma difficult to differentiate from primary hepatic marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue

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    Hepatic pseudolymphoma (HPL) and primary hepatic marginal zone B cell lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) are rare diseases and the differential diagnosis between these two entities is sometimes difficult. We herein report a 56-year-old Japanese woman who was pointed out to have a space occupying lesion in the left lateral segment of the liver. Hepatitis viral-associated antigen/antibody was negative and liver function tests including lactic dehydrogenase, peripheral blood count, tumor markers and soluble interleukin-2 receptor were all within normal limit. Imaging study using computed tomography and magnetic resonance imaging were not typical for hepatocellular carcinoma, cholangiocarcinoma, or other metastatic cancer. Fluorodeoxyglucose-positron emission tomography examination integrated with computed tomography scanning showed high standardized uptake value in the solitary lesion in the liver. Under a diagnosis of primary liver neoplasm, laparoscopic-assisted lateral segmentectomy was performed. Liver tumor of maximal 1.0 cm in diameter was consisted of aggregation of lymphocytes of predominantly B-cell, containing multiple lymphocyte follicles positive for CD10 and bcl-2, consistent with a diagnosis of HPL rather than MALT lymphoma, although a definitive differentiation was pending. The background liver showed non-alcoholic fatty liver disease/early non-alcoholic steatohepatitis. The patient is currently doing well with no sign of relapse 13 months after the surgery. Since the accurate diagnosis is difficult, laparoscopic approach would provide a reasonable procedure of diagnostic and therapeutic advantage with minimal invasiveness for patients. Considering that the real nature of this entity remains unclear, vigilant follow-up of patient is essential

    Combination Strategies for Targeted Delivery of Nanoparticles for Cancer Therapy

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    Pharmaceuticals, and more recently biopharmaceuticals, have become the mainstay for antineoplastic treatments in combination with surgical interventions and radiation therapy. In recent years, advances have been made in the development of nano-technological interventions for the treatment of cancer alone or in combination with existing therapeutic modalities. Nanotechnology used for therapeutic drug delivery and sensitization of photodynamic, sonodynamic and radiotherapy are now being tested in preclinical and clinical trials for the treatment of cancer. This article will review the current state of the art for nanotechnology therapies with an emphasis on targeted drug delivery and the observed and likely benefits when used in combination with existing therapeutic approaches

    The COVID-19 pandemic: a letter to G20 leaders

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