Target localisation is one of the key technologies and a performance metric in underwater acoustic sensor networks. A number of range-free and range-based localisation algorithms are proposed. Among ...them a range-based localisation algorithm: weighted centroid localisation (WCL) is widely used due to the relatively simple implementation and better localisation. The accuracy of WCL, however, is reduced when the sensor nodes are farther from the centre or inappropriate nodes are selected to perform the localisation. This study proposes a novel and an efficient node optimisation algorithm based on received signal strength and weighted centroid. The proposed algorithm consists of three stages: (a) to estimate a rough region of the target node using bearing line and azimuth; (b) to calculate the optimal localisation region by the optimal localisation region function, and then (c) compare the overlap area of the rough region of the target node and the optimal localisation region to select the optimal localisation node. Simulation experiments show that the proposed optimal localisation region function can accurately represent the optimal localisation region of the geometrical figure, composed of different nodes. The study compares the performance of our proposed algorithm with the typical WCL algorithm, and clearly shows significant improvement in the localisation accuracy.
Localisation microscopy of individual molecules allows one to bypass the diffraction limit, revealing cellular organisation on a nanometric scale. This method, which relies on spatial analysis of the ...signal emitted by molecules, is often limited to the observation of biological objects at shallow depths, or with very few aberrations. The introduction of a temporal parameter into the localisation process through a time‐modulated excitation was recently proposed to address these limitations. This method, called ModLoc, is demonstrated here with an alternative flexible strategy. In this implementation, to encode the time‐modulated excitation a digital micromirror device (DMD) is used in combination with a fast demodulation approach, and provides a twofold enhancement in localisation precision.
Layout: Nowadays, we can use an optical microscope to observe how proteins are organised in 3D within a cell at the nanoscale. By carefully controlling the emission of molecules in both space and time, we can overcome the limitations set by the diffraction limit. This allows us to pinpoint the exact location of molecules more precisely. However, the usual spatial analysis method limits observations to shallow depths or causing low distortion of optical waves.
To overcome these restrictions, a recent approach introduces a temporal element to the localisation process. This involves changing the illumination over time to enhance the precision of localisation. This method, known as ModLoc, is showcased here using a flexible and alternative strategy. In this setup, a matrix of micrometric mirrors, working together with a fast demodulation optical module, is used to encode and decode the time‐modulated information. This combination results in a twofold improvement in localisation precision.
Pipelines are widely used for the transportation of hydrocarbon fluids over millions of miles all over the world. The structures of the pipelines are designed to withstand several environmental ...loading conditions to ensure safe and reliable distribution from point of production to the shore or distribution depot. However, leaks in pipeline networks are one of the major causes of innumerable losses in pipeline operators and nature. Incidents of pipeline failure can result in serious ecological disasters, human casualties and financial loss. In order to avoid such menace and maintain safe and reliable pipeline infrastructure, substantial research efforts have been devoted to implementing pipeline leak detection and localisation using different approaches. This paper discusses pipeline leakage detection technologies and summarises the state-of-the-art achievements. Different leakage detection and localisation in pipeline systems are reviewed and their strengths and weaknesses are highlighted. Comparative performance analysis is performed to provide a guide in determining which leak detection method is appropriate for particular operating settings. In addition, research gaps and open issues for development of reliable pipeline leakage detection systems are discussed.
One of the most vexing problems for governments is building controversial facilities that serve the needs of all citizens but have adverse consequences for host communities. Policymakers must decide ...not only where to locate often unwanted projects but also what methods to use when interacting with opposition groups. InSite Fights, Daniel P. Aldrich gathers quantitative evidence from close to five hundred municipalities across Japan to show that planners deliberately seek out acquiescent and unorganized communities for such facilities in order to minimize conflict.
When protests arise over nuclear power plants, dams, and airports, agencies regularly rely on the coercive powers of the modern state, such as land expropriation and police repression. Only under pressure from civil society do policymakers move toward financial incentives and public relations campaigns. Through fieldwork and interviews with bureaucrats and activists, Aldrich illustrates these dynamics with case studies from Japan, France, and the United States. The incidents highlighted inSite Fightsstress the importance of developing engaged civil society even in the absence of crisis, thereby making communities both less attractive to planners of controversial projects and more effective at resisting future threats.
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We propose a novel attention gate (AG) model for medical image analysis that automatically learns to focus on target structures of varying shapes and sizes. Models trained with AGs ...implicitly learn to suppress irrelevant regions in an input image while highlighting salient features useful for a specific task. This enables us to eliminate the necessity of using explicit external tissue/organ localisation modules when using convolutional neural networks (CNNs). AGs can be easily integrated into standard CNN models such as VGG or U-Net architectures with minimal computational overhead while increasing the model sensitivity and prediction accuracy. The proposed AG models are evaluated on a variety of tasks, including medical image classification and segmentation. For classification, we demonstrate the use case of AGs in scan plane detection for fetal ultrasound screening. We show that the proposed attention mechanism can provide efficient object localisation while improving the overall prediction performance by reducing false positives. For segmentation, the proposed architecture is evaluated on two large 3D CT abdominal datasets with manual annotations for multiple organs. Experimental results show that AG models consistently improve the prediction performance of the base architectures across different datasets and training sizes while preserving computational efficiency. Moreover, AGs guide the model activations to be focused around salient regions, which provides better insights into how model predictions are made. The source code for the proposed AG models is publicly available.
Peroxisomes are ubiquitous membrane-bound organelles, and aberrant localisation of peroxisomal proteins contributes to the pathogenesis of several disorders. Many computational methods focus on ...assigning protein sequences to subcellular compartments, but there are no specific tools tailored for the sub-localisation (matrix vs. membrane) of peroxisome proteins. We present here In-Pero, a new method for predicting protein sub-peroxisomal cellular localisation. In-Pero combines standard machine learning approaches with recently proposed multi-dimensional deep-learning representations of the protein amino-acid sequence. It showed a classification accuracy above 0.9 in predicting peroxisomal matrix and membrane proteins. The method is trained and tested using a double cross-validation approach on a curated data set comprising 160 peroxisomal proteins with experimental evidence for sub-peroxisomal localisation. We further show that the proposed approach can be easily adapted (In-Mito) to the prediction of mitochondrial protein localisation obtaining performances for certain classes of proteins (matrix and inner-membrane) superior to existing tools.
Mitochondrial dysfunction is implicated in a wide range of human disorders including many neurodegenerative and cardiovascular diseases, metabolic diseases, cancers, and respiratory disorders. ...Studies have suggested the potential of l-ergothioneine (ET), a unique dietary thione, to prevent mitochondrial damage and improve disease outcome. Despite this, no studies have definitively demonstrated uptake of ET into mitochondria. Moreover, the expression of the known ET transporter, OCTN1, on the mitochondria remains controversial. In this study, we utilise mass spectrometry to demonstrate direct ET uptake in isolated mitochondria as well as its presence in mitochondria isolated from ET-treated cells and animals. Mitochondria isolated from OCTN1 knockout mice tissues, have impaired but still detectable ET uptake, raising the possibility of alternative transporter(s) which may facilitate ET uptake into the mitochondria. Our data confirm that ET can enter mitochondria, providing a basis for further work on ET in the prevention of mitochondrial dysfunction in human disease.
•Ergothioneine (ET) is taken up and accumulated by mitochondria in cells and animals.•Isolated mitochondria take up ET even in the absence of the ET transporter, OCTN1.•Other transporter(s) are probably involved in mitochondrial uptake of ergothioneine.
A Damage Indication Function (DIF) is developed in this work to localise the damage on a structure. The novelty is that this is the first work proposing a time response correlation-based damage ...localisation method. To identify the damage, dynamic time response is measured by several sensors placed on the structure using a user excitation. A set of damaged finite element models is developed. Each damage model has only one specified damage but at different locations. The collection of the damage models forms a complete damage grid. The same user excitation is applied to each damage model to generate an analytical response. The test response is then correlated with the model response of each damage model. The highest correlation between the test response and the model response of all damage models would indicate the damage location on the test structure. A plate-type structure is used to demonstrate the power and effectiveness of DIF experimentally.
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