70 research outputs found

    Innovative Self-Organization Wireless Sensor Networks for Electrical Power Systems

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    Wireless Sensor Networks (WSNs) gather information for electrical power systems and help to manage demand Response and demand side strategies. Optimization of WSNs depends on their physical deployment, and it will bring to the fore a very focused number of parameters to be optimized. Selforganization of WSNs is an important issue to be considered, and it requires the nodes to form a network by collaboration with each other without using manual intervention. Moreover, the WSNs implemented in electrical power systems should be secured and energy efficient in order to provide highly reliable data for monitoring and control. In this paper, we will propose Self-Organization WSNs with Security and Energy-efficient Clustering algorithms (SOSEC) including cluster formation, data encryption keys establishment and management, and an energy efficient routing protocol. SOSEC can optimize the energy efficiency of the whole network and ensure a secured channel for data transmissions in WSNs for electrical power systems

    New energy efficient routing algorithm for Wireless Sensor Network

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    Energy efficiency is the most challenging topic in Wireless Sensor Networks (WSN). Because of the increasing demands of various applications, and the constraints of energy, memory and computational power of the WSN nodes, many studies have focused on these areas in recent years. Researchers have proposed a variety of protocols such as LEACH, PEGASIS, HEED, TEEN, etc. In this paper, we will discuss how energy efficiency is affected by scaling, i.e. different network sizes, and by different routing algorithms. With the increasing applications of large scale WSNs, such as smart grid and environmental monitoring. We will propose a new routing algorithm to optimize the energy efficiency by reducing the number and total transmissions distance in order to save energy. Simulations suggest that the proposed algorithm will be more energy efficient in medium to large scale wireless sensor networks

    Perspective Chapter: Functional Human Brain Connectome in Deep Brain Stimulation (DBS) for Parkinson’s Disease (PD)

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    Historically, the success of DBS depends on the accuracy of electrode localization in neuroanatomical structures. With time, diffusion-weighted magnetic resonance imaging (MRI) and functional MRI have been introduced to study the structural connectivity and functional connectivity in patients with neurodegenerative disorders such as PD. Unlike the traditional lesion-based stimulation theory, this new network stimulation theory suggested that stimulation of specific brain circuits can modulate the pathological network and restore it to its physiological state, hence causing normalization of human brain connectome in PD patients. In this review, we discuss the feasibility of network-based stimulation and the use of connectomic DBS in PD

    Hierarchical routing protocols for wireless sensor network: a compressive survey

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    Wireless Sensor Networks (WSNs) are one of the key enabling technologies for the Internet of Things (IoT). WSNs play a major role in data communications in applications such as home, health care, environmental monitoring, smart grids, and transportation. WSNs are used in IoT applications and should be secured and energy efficient in order to provide highly reliable data communications. Because of the constraints of energy, memory and computational power of the WSN nodes, clustering algorithms are considered as energy efficient approaches for resource-constrained WSNs. In this paper, we present a survey of the state-of-the-art routing techniques in WSNs. We first present the most relevant previous work in routing protocols surveys then highlight our contribution. Next, we outline the background, robustness criteria, and constraints of WSNs. This is followed by a survey of different WSN routing techniques. Routing techniques are generally classified as flat, hierarchical, and location-based routing. This survey focuses on the deep analysis of WSN hierarchical routing protocols. We further classify hierarchical protocols based on their routing techniques. We carefully choose the most relevant state-of-the-art protocols in order to compare and highlight the advantages, disadvantage and performance issues of each routing technique. Finally, we conclude this survey by presenting a comprehensive survey of the recent improvements of Low-Energy Adaptive Clustering Hierarchy (LEACH) routing protocols and a comparison of the different versions presented in the literature

    Long-term prognostic impact of cardiovascular comorbidities in patients with prostate cancer receiving androgen deprivation therapy: A population-based competing risk analysis.

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    Our study investigated how adverse cardiovascular outcomes are impacted by cardiovascular comorbidities in patients with prostate cancer treated by androgen deprivation therapy (ADT). Using prospective, population-based data, all Hong Kong patients with prostate cancer who received ADT during 1 January 1993 to 3 March 2021 were identified and followed up for the endpoint of cardiovascular hospitalization/mortality until 31 September 2021, whichever earlier. Multivariable competing risk regression was used to compare the endpoint's cumulative incidence between different combinations of major cardiovascular comorbidities (heart failure [HF], myocardial infarction [MI], stroke and/or arrhythmia), with noncardiovascular death as competing event. Altogether, 13 537 patients were included (median age 75.9 [interquartile range 70.0-81.5] years old; median follow-up 3.3 [1.5-6.7] years). Compared to those with none of prior HF/MI/stroke/arrhythmia, the incidence of the endpoint was not different in those with only stroke (subhazard ratio [SHR] 1.06 [95% confidence interval (CI): 0.92-1.23], P = .391), but was higher in those with only HF (SHR 1.67 [1.37-2.02], P < .001), arrhythmia (SHR 1.63 [1.35-1.98], P < .001) or MI (SHR 1.43 [1.14-1.79], P = .002). Those with ≥2 of HF/MI/stroke/arrhythmia had the highest incidence of the endpoint (SHR 1.94 [1.62-2.33], P < .001), among whom different major cardiovascular comorbidities had similar prognostic impacts, with the number of comorbidities present being significantly prognostic instead. In conclusion, in patients with prostate cancer receiving ADT, the sole presence of HF, MI or arrhythmia, but not stroke, may be associated with elevated cardiovascular risks. In those with ≥2 of HF/MI/stroke/arrhythmia, the number of major cardiovascular comorbidities may be prognostically more important than the type of comorbidities. [Abstract copyright: © 2023 The Authors. International Journal of Cancer published by John Wiley & Sons Ltd on behalf of UICC.

    Statin use and mortality risk in Asian patients with prostate cancer receiving androgen deprivation therapy: A population-based cohort study

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    Background This study aimed to examine the associations between the use of statins concurrent with androgen deprivation therapy (ADT) and the risks of mortality in Asian patients diagnosed with prostate cancer (PCa). Methods Adult patients (≥18 years old) diagnosed with PCa who were receiving any form of ADT and were being treated at public hospitals in Hong Kong from December 1999 to March 2021 were retrospectively identified, with follow-up conducted until September 2021. Patients who had received medical castration for <180 days without subsequent bilateral orchidectomy, those who had used statins concurrently with ADT for <180 days, and those with missing baseline total cholesterol levels were excluded. Statin users were defined as individuals who had used statins for ≥180 days concurrent with ADT, while non-users were those who had not used any statins. PCa-related mortality was the primary outcome, while all-cause mortality served as the secondary outcome. Inverse probability treatment weighting was employed to balance the covariates. Results A total of 4920 patients were included, consisting of 2578 statin users and 2342 non-users (mean age 76.1 ± 8.2 years). Over a mean follow-up period of 4.2 ± 3.3 years, it was observed that statin users had significantly lower risks of both PCa-related mortality (weighted hazard ratio [wHR] 0.56 [95% confidence interval (CI) 0.48, 0.65], p < 0.001) and all-cause mortality (wHR 0.57 [95% CI 0.51, 0.63], p < 0.001), regardless of the type of ADT used. Notably, these associations were more pronounced among patients with less advanced PCa, as indicated by the absence of androgen receptor antagonist or chemotherapy usage (p value for interaction <0.001 for both outcomes). Conclusion(s) The use of statins concurrent with ADT was associated with reduced mortality risks among Asian patients with PCa. These findings suggest the need for additional research to explore the potential role of statins in the treatment of PCa patients

    Metformin use and hospital attendance-related resources utilization among diabetic patients with prostate cancer on androgen deprivation therapy: A population-based cohort study

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    Background Androgen deprivation therapy (ADT), used increasingly in the treatment of prostate cancer (PCa), negatively influences glycemic control in diabetes and is associated with an increased risk of diabetes complications where hospitalization commonly ensues. Metformin could decrease the metabolic consequences of ADT and enhance its effect. This study examined the association of metformin use with healthcare resources utilization among diabetic, PCa patients receiving ADT. Methods Diabetic adults with PCa on ADT in Hong Kong between December 1999 and March 2021 were identified. Patients with <6 months of concurrent metformin and ADT use were excluded. All included patients were followed up until September 2021. The outcomes were hospital attendances and related costs. Results In total, 1,284 metformin users and 687 non-users were studied. Over 8,045 person-years, 9,049 accident and emergency (A&E), and 21,262 inpatient attendances, with 11,2781 days of hospitalization were observed. Metformin users had significantly fewer A&E attendances (incidence rate ratio (IRR): 0.61 [95% confidence interval 0.54–0.69], p < 0.001), inpatient attendances (IRR: 0.57 [0.48–0.67], p < 0.001), and days of hospitalization (IRR: 0.55 [0.42–0.72], p < 0.001). Annual attendance costs were lower for metformin users than non-users (cost ratio: 0.28 [0.10–0.80], p = 0.017). Conclusions Metformin use was associated with decreased hospital attendances, days of hospitalization, and associated costs, which could help reduce healthcare resource utilization following ADT in the treatment of PCa

    Prognostic significance of minichromosome maintenance proteins in breast cancer.

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    A role for the minichromosome maintenance (MCM) proteins in cancer initiation and progression is slowly emerging. Functioning as a complex to ensure a single chromosomal replication per cell cycle, the six family members have been implicated in several neoplastic disease states, including breast cancer. Our study aim to investigate the prognostic significance of these proteins in breast cancer. We studied the expression of MCMs in various datasets and the associations of the expression with clinicopathological parameters. When considered alone, high level MCM4 overexpression was only weakly associated with shorter survival in the combined breast cancer patient cohort (n = 1441, Hazard Ratio = 1.31; 95% Confidence Interval = 1.11-1.55; p = 0.001). On the other hand, when we studied all six components of the MCM complex, we found that overexpression of all MCMs was strongly associated with shorter survival in the same cohort (n = 1441, Hazard Ratio = 1.75; 95% Confidence Interval = 1.31-2.34; p < 0.001), suggesting these MCM proteins may cooperate to promote breast cancer progression. Indeed, their expressions were significantly correlated with each other in these cohorts. In addition, we found that increasing number of overexpressed MCMs was associated with negative ER status as well as treatment response. Together, our findings are reproducible in seven independent breast cancer cohorts, with 1441 patients, and suggest that MCM profiling could potentially be used to predict response to treatment and prognosis in breast cancer patients.published_or_final_versio

    Temporal trends in cardiovascular burden among patients with prostate cancer receiving androgen deprivation therapy: a population-based cohort study

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    Background Although androgen deprivation therapy (ADT) is associated with cardiovascular risks, the extent and temporal trends of cardiovascular burden amongst patients with prostate cancer receiving ADT are unclear. Methods This retrospective cohort study analyzed adults with PCa receiving ADT between 1993–2021 in Hong Kong, with follow-up until 31/9/2021 for the primary outcome of major adverse cardiovascular events (MACE; composite of cardiovascular mortality, myocardial infarction, stroke, and heart failure), and the secondary outcome of mortality. Patients were stratified into four groups by the year of ADT initiation for comparisons. Results Altogether, 13,537 patients were included (mean age 75.5 ± 8.5 years old; mean follow-up 4.7 ± 4.3 years). More recent recipients of ADT had more cardiovascular risk factors and used more cardiovascular or antidiabetic medications. More recent recipients of ADT had higher risk of MACE (most recent (2015–2021) vs least recent (1993–2000) group: hazard ratio 1.33 [1.11, 1.59], P = 0.002; Ptrend < 0.001), but lower risk of mortality (hazard ratio 0.76 [0.70, 0.83], P < 0.001; Ptrend < 0.001). The 5-year risk of MACE and mortality for the most recent group were 22.5% [20.9%, 24.2%] and 52.9% [51.3%, 54.6%], respectively. Conclusions Cardiovascular risk factors were increasingly prevalent amongst patients with prostate cancer receiving ADT, with increasing risk of MACE despite decreasing mortality

    HbA1c variability and cardiovascular events in patients with prostate cancer receiving androgen deprivation therapy

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    Androgen deprivation therapy (ADT) worsens glycaemic control and cardiovascular outcomes. The prognostic value of visit-to-visit HbA1c variability (VVHV) has been unexplored in prostate cancer (PCa) patients receiving ADT. To explore the effect of ADT on VVHV and the cardiovascular prognostic value of VVHV. PCa patients receiving ADT in Hong Kong between January 1, 1993 and March 31, 2021 were included in this retrospective cohort study. Those with fewer than three HbA1c results available within 3 yr after ADT initiation, <6 mo of ADT, missing baseline HbA1c, prior diagnosis of any component of major adverse cardiovascular events (MACEs), and MACEs occurring within 3 yr were excluded. Patients were followed up until September 31, 2021. The outcome was MACEs (composite of heart failure, myocardial infarction, stroke, and cardiovascular mortality). VVHV was calculated from HbA1c levels within 3 yr after and, separately where available, before ADT initiation using coefficient of variation (CV; standard deviation [SD] divided by mean) and average real variability (ARV; average difference between consecutive measurements). Altogether, 1065 patients were analysed (median age 74.4 yr old [interquartile range 68.3-79.5 yr]). In 709 patients with VVHV available before and after ADT initiation, VVHV increased after ADT initiation (  < 0.001), with 473 (66.2%) and 474 (66.9%) having increased CV and ARV, respectively. Over a median follow-up of 4.3 yr (2.8-6.7 yr), higher VVHV was associated with a higher risk of MACEs (adjusted hazard ratio [per SD] for CV 1.21 [95% confidence interval: 1.02, 1.43],  = 0.029; ARV 1.25 [1.06, 1.48],  = 0.008). Limitations included residual confounding and selection bias. In PCa patients receiving ADT, VVHV increased after ADT initiation. Higher VVHV was associated with an increased risk of MACEs. In prostate cancer patients receiving androgen deprivation therapy (ADT), glycaemic control is less stable after initiating ADT, which was associated with an increased cardiovascular risk. [Abstract copyright: © 2022 The Authors. Published by Elsevier B.V. on behalf of European Association of Urology.
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