The Experts below are selected from a list of 4563 Experts worldwide ranked by ideXlab platform
Jolanta Zakrzewskaczerwinska - One of the best experts on this subject based on the ideXlab platform.
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dynamics of chromosome replication and its relationship to predatory Attack lifestyles in bdellovibrio bacteriovorus
Applied and Environmental Microbiology, 2019Co-Authors: łukasz Makowski, Damian Trojanowski, Carey Lambert, Elizabeth R Sockett, Rob Till, Rebecca Lowry, Jolanta ZakrzewskaczerwinskaAbstract:Bdellovibrio bacteriovorus is a small Gram-negative, obligate predatory bacterium that is largely found in wet, aerobic environments (e.g., soil). This bacterium Attacks and invades other Gram-negative bacteria, including animal and plant pathogens. The intriguing life cycle of B. bacteriovorus consists of two phases: a free-living nonreplicative Attack phase, in which the predatory bacterium searches for its prey, and a reproductive phase, in which B. bacteriovorus degrades a host's macromolecules and reuses them for its own growth and chromosome replication. Although the cell biology of this predatory bacterium has gained considerable interest in recent years, we know almost nothing about the dynamics of its chromosome replication. Here, we performed a real-time investigation into the subcellular localization of the replisome(s) in single cells of B. bacteriovorus Our results show that in B. bacteriovorus, chromosome replication takes place only during the reproductive phase and exhibits a novel spatiotemporal arrangement of replisomes. The replication process starts at the Invasive pole of the predatory bacterium inside the prey cell and proceeds until several copies of the chromosome have been completely synthesized. Chromosome replication is not coincident with the predator cell division, and it terminates shortly before synchronous predator filament septation occurs. In addition, we demonstrate that if this B. bacteriovorus life cycle fails in some cells of Escherichia coli, they can instead use second prey cells to complete their life cycle.IMPORTANCE New strategies are needed to combat multidrug-resistant bacterial infections. Application of the predatory bacterium Bdellovibrio bacteriovorus, which kills other bacteria, including pathogens, is considered promising for combating bacterial infections. The B. bacteriovorus life cycle consists of two phases, a free-living, Invasive Attack phase and an intracellular reproductive phase, in which this predatory bacterium degrades the host's macromolecules and reuses them for its own growth. To understand the use of B. bacteriovorus as a "living antibiotic," it is first necessary to dissect its life cycle, including chromosome replication. Here, we present a real-time investigation into subcellular localization of chromosome replication in a single cell of B. bacteriovorus This process initiates at the invasion pole of B. bacteriovorus and proceeds until several copies of the chromosome have been completely synthesized. Interestingly, we demonstrate that some cells of B. bacteriovorus require two prey cells sequentially to complete their life cycle.
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dynamics of chromosome replication and its relationship to predatory Attack lifestyles in bdellovibrio bacteriovorus
bioRxiv, 2019Co-Authors: Lukasz Makowski, Damian Trojanowski, Carey Lambert, Elizabeth R Sockett, Rob Till, Rebecca Lowry, Jolanta ZakrzewskaczerwinskaAbstract:Abstract Bdellovibrio bacteriovorus is a small Gram-negative, an obligate predatory bacterium that is largely found in wet, aerobic environments (i.e. soil). This bacterium Attacks and invades other Gram-negative bacteria, including animal and plant pathogens. The intriguing life cycle of B. bacteriovorus consists of two phases: a free-living non-replicative Attack phase wherein the predatory bacterium searches for its prey, and a reproductive phase, in which B. bacteriovorus degrades a host’s macromolecules and reuses them for its own growth and chromosome replication. Although the cell biology of this predatory bacterium has gained considerable interest in recent years, we know almost nothing about the dynamics of chromosome replication in B. bacteriovorus. Here, we performed a real-time investigation into the subcellular localization of the replisome(s) in single cells of B. bacteriovorus. Our results confirm that in B. bacteriovorus chromosome replication fires only during the reproductive phase, and show for the first time that this predatory bacterium exhibits a novel spatiotemporal arrangement of chromosome replication. The replication process starts at the Invasive pole of the predatory bacterium inside the prey cell and proceeds until several copies of the chromosome have been completely synthesized. This chromosome replication is not coincident with the predator-cell division, and it terminates shortly before synchronous predator-filament septation occurs. In addition, we demonstrate that if this lifecycle fails in some cells of B. bacteriovorus, they can instead use two prey cells sequentially to complete their life cycle. Importance New strategies are needed to combat multidrug-resistant bacterial infections. Application of the predatory bacterium, Bdellovibrio bacteriovorus, which kills other bacteria including pathogens, is considered promising for bacterial infections. The B. bacteriovorus life cycle consists of two phases, a free-living, Invasive Attack phase and an intracellular reproductive phase, in which this predatory bacterium degrades the host’s macromolecules and reuses them for its own growth. To understand the use of B. bacteriovorus as a ‘living antibiotic’, it is first necessary to dissect its life cycle including chromosome replication. Here, we present for the first time a real-time investigation into subcellular localization of chromosome replication in a single cells of B. bacteriovorus. This process initiates at the invasion pole of B. bacteriovorus and proceeds until several copies of the chromosome have been completely synthesized. Interestingly, we demonstrate that some cells of B. bacteriovorus require two prey cells sequentially to complete their life cycle.
Zhenglin Liu - One of the best experts on this subject based on the ideXlab platform.
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a trustworthy key generation prototype based on ddr3 puf for wireless sensor networks
Sensors, 2014Co-Authors: Wenchao Liu, Zhenhua Zhang, Zhenglin LiuAbstract:Secret key leakage in wireless sensor networks (WSNs) is a high security risk especially when sensor nodes are deployed in hostile environment and physically accessible to Attackers. With nowadays semi/fully-Invasive Attack techniques Attackers can directly derive the cryptographic key from non-volatile memory (NVM) storage. Physically Unclonable Function (PUF) is a promising technology to resist node capture Attacks, and it also provides a low cost and tamper-resistant key provisioning solution. In this paper, we designed a PUF based on double-data-rate SDRAM Type 3 (DDR3) memory by exploring its memory decay characteristics. We also described a prototype of 128-bit key generation based on DDR3 PUF with integrated fuzzy extractor. Due to the wide adoption of DDR3 memory in WSN, our proposed DDR3 PUF technology with high security levels and no required hardware changes is suitable for a wide range of WSN applications.
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a trustworthy key generation prototype based on ddr3 puf for wireless sensor networks
International Symposium on Computer Consumer and Control, 2014Co-Authors: Wenchao Liu, Zhenhua Zhang, Zhenglin LiuAbstract:In wireless sensor security systems, the security key of sensor node is usually stored in the non-volatile memory. By capturing the nodes, it is possible for Attackers to perform a physical Invasive Attack to extract the key illegally. Physical unclonable function (PUF) has its innate immunity to physical Invasive Attacks, which can effectively generate keys from manufacturing variability of a device. The feasibility of DRAM PUF based on DDR3 memory is studied in the paper though theory analysis and experiments. A prototype of key extraction based on DRAM PUF is proposed. As DRAM is widely used as memory device in WSN nodes, the generation of DRAM PUF keys need no extra hardware, which making it applicable for compact WSN circuits.
Suleyman Uludag - One of the best experts on this subject based on the ideXlab platform.
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timely detection and mitigation of iot based cyberAttacks in the smart grid
Journal of The Franklin Institute-engineering and Applied Mathematics, 2021Co-Authors: Yasin Yilmaz, Suleyman UludagAbstract:Abstract The ongoing changes, updates, and upgrades of the Smart Grid infrastructure open up new cybersecurity challenges whose successful and satisfactory handling is a vital necessity for a viable future of these initiatives. The characteristic of the Smart Grid that leads to physical damage and cascading power failures amplifies the severity of security breaches. A set of recent successful Distributed Denial-of-Service (DDoS) Attacks on the Internet, facilitated by the proliferation of the Internet-of-Things (IoT) powered botnets, shows that the Smart Grid may become the target and likely victim of such an Attack, potentially leaving catastrophic outage of power service to millions of people. In this paper, under a hierarchical data collection infrastructure we propose a general and scalable mitigation approach, called Minimally Invasive Attack Mitigation via Detection Isolation and Localization (MIAMI-DIL), based on an online and nonparametric anomaly detection algorithm which is scalable and capable of timely detection. We provide a proof-of-concept by means of simulations to show the efficacy and scalability of the proposed approach.
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mitigating iot based cyberAttacks on the smart grid
International Conference on Machine Learning and Applications, 2017Co-Authors: Yasin Yilmaz, Suleyman UludagAbstract:The impact of cybersecurity Attacks on the Smart Grid may cause cyber as well as physical damages, as clearly shown in the recent Attacks on the power grid in Ukraine where consumers were left without power. A set of recent successful Distributed Denial-of-Service (DDoS) Attacks on the Internet, facilitated by the proliferation of the Internet-of-Things powered botnets, shows that it is just a matter of time before the Smart Grid, as one of the most attractive critical infrastructure systems, becomes the target and likely victim of similar Attacks, potentially leaving catastrophic disruption of power service to millions of people. It is in this context that we propose a scalable mitigation approach, referred to as Minimally Invasive Attack Mitigation via Detection Isolation and Localization (MIAMI-DIL), under a hierarchical data collection infrastructure. We provide a proofof- concept by means of simulations which show the efficacy and scalability of the proposed approach.
Wenchao Liu - One of the best experts on this subject based on the ideXlab platform.
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a trustworthy key generation prototype based on ddr3 puf for wireless sensor networks
Sensors, 2014Co-Authors: Wenchao Liu, Zhenhua Zhang, Zhenglin LiuAbstract:Secret key leakage in wireless sensor networks (WSNs) is a high security risk especially when sensor nodes are deployed in hostile environment and physically accessible to Attackers. With nowadays semi/fully-Invasive Attack techniques Attackers can directly derive the cryptographic key from non-volatile memory (NVM) storage. Physically Unclonable Function (PUF) is a promising technology to resist node capture Attacks, and it also provides a low cost and tamper-resistant key provisioning solution. In this paper, we designed a PUF based on double-data-rate SDRAM Type 3 (DDR3) memory by exploring its memory decay characteristics. We also described a prototype of 128-bit key generation based on DDR3 PUF with integrated fuzzy extractor. Due to the wide adoption of DDR3 memory in WSN, our proposed DDR3 PUF technology with high security levels and no required hardware changes is suitable for a wide range of WSN applications.
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a trustworthy key generation prototype based on ddr3 puf for wireless sensor networks
International Symposium on Computer Consumer and Control, 2014Co-Authors: Wenchao Liu, Zhenhua Zhang, Zhenglin LiuAbstract:In wireless sensor security systems, the security key of sensor node is usually stored in the non-volatile memory. By capturing the nodes, it is possible for Attackers to perform a physical Invasive Attack to extract the key illegally. Physical unclonable function (PUF) has its innate immunity to physical Invasive Attacks, which can effectively generate keys from manufacturing variability of a device. The feasibility of DRAM PUF based on DDR3 memory is studied in the paper though theory analysis and experiments. A prototype of key extraction based on DRAM PUF is proposed. As DRAM is widely used as memory device in WSN nodes, the generation of DRAM PUF keys need no extra hardware, which making it applicable for compact WSN circuits.
łukasz Makowski - One of the best experts on this subject based on the ideXlab platform.
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dynamics of chromosome replication and its relationship to predatory Attack lifestyles in bdellovibrio bacteriovorus
Applied and Environmental Microbiology, 2019Co-Authors: łukasz Makowski, Damian Trojanowski, Carey Lambert, Elizabeth R Sockett, Rob Till, Rebecca Lowry, Jolanta ZakrzewskaczerwinskaAbstract:Bdellovibrio bacteriovorus is a small Gram-negative, obligate predatory bacterium that is largely found in wet, aerobic environments (e.g., soil). This bacterium Attacks and invades other Gram-negative bacteria, including animal and plant pathogens. The intriguing life cycle of B. bacteriovorus consists of two phases: a free-living nonreplicative Attack phase, in which the predatory bacterium searches for its prey, and a reproductive phase, in which B. bacteriovorus degrades a host's macromolecules and reuses them for its own growth and chromosome replication. Although the cell biology of this predatory bacterium has gained considerable interest in recent years, we know almost nothing about the dynamics of its chromosome replication. Here, we performed a real-time investigation into the subcellular localization of the replisome(s) in single cells of B. bacteriovorus Our results show that in B. bacteriovorus, chromosome replication takes place only during the reproductive phase and exhibits a novel spatiotemporal arrangement of replisomes. The replication process starts at the Invasive pole of the predatory bacterium inside the prey cell and proceeds until several copies of the chromosome have been completely synthesized. Chromosome replication is not coincident with the predator cell division, and it terminates shortly before synchronous predator filament septation occurs. In addition, we demonstrate that if this B. bacteriovorus life cycle fails in some cells of Escherichia coli, they can instead use second prey cells to complete their life cycle.IMPORTANCE New strategies are needed to combat multidrug-resistant bacterial infections. Application of the predatory bacterium Bdellovibrio bacteriovorus, which kills other bacteria, including pathogens, is considered promising for combating bacterial infections. The B. bacteriovorus life cycle consists of two phases, a free-living, Invasive Attack phase and an intracellular reproductive phase, in which this predatory bacterium degrades the host's macromolecules and reuses them for its own growth. To understand the use of B. bacteriovorus as a "living antibiotic," it is first necessary to dissect its life cycle, including chromosome replication. Here, we present a real-time investigation into subcellular localization of chromosome replication in a single cell of B. bacteriovorus This process initiates at the invasion pole of B. bacteriovorus and proceeds until several copies of the chromosome have been completely synthesized. Interestingly, we demonstrate that some cells of B. bacteriovorus require two prey cells sequentially to complete their life cycle.
