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The ability to slow or reverse biological ageing would have major implications for mitigating disease risk and maintaining vitality1. Although an increasing number of interventions show promise for rejuvenation2, their effectiveness on disparate cell types across the body and the molecular pathways susceptible to rejuvenation remain largely unexplored. Here we performed single-cell RNA sequencing on 20 organs to reveal cell-type-specific responses to young and aged blood in heterochronic parabiosis. Adipose mesenchymal stromal cells, haematopoietic stem cells and hepatocytes are among those cell types that are especially responsive. On the pathway level, young blood invokes new gene sets in addition to reversing established ageing patterns, with the global rescue of genes encoding electron transport chain subunits pinpointing a prominent role of mitochondrial function in parabiosis-mediated rejuvenation. We observed an almost universal loss of gene expression with age that is largely mimicked by parabiosis: aged blood reduces global gene expression, and young blood restores it in select cell types. Together, these data lay the groundwork for a systemic understanding of the interplay between blood-borne factors and cellular integrity.

The use of Unmanned Aerial Vehicles (UAV) in every field is increasing rapidly. In order for UAVs to perform their duties correctly, they must be able to maintain continuous communication with ground stations. The use of WiFi wireless communication protocol has increased due to its high bandwidth. One of the most important threats that can threaten this type of communication is Denial of Service (DoS) attacks. In the event of such an attack, the UAV becomes inaccessible and may crash. Especially when the open port number is known, it becomes much easier to perform attacks that consume the resources of the drone. In this study, a mechanism is proposed to eliminate or at least mitigate the attack risk. This mechanism enables UAVs using wireless communication (WiFi) to communicate using TCP over UDP using middleware. In addition, by periodically changing the UDP open ports with a secret port number sequence known to both parties, it prevents the attacker from using the open port for a long time and renders the attack ineffective. In this study, the effects of the port hopping method on UAVs are evaluated. Test results on real systems shows that the proposed system makes the communication system of UAVs more resistant to DoS attacks by 91.2%., İnsansız Hava Araçlarının (İHA) her alanda kullanımı hızlı bir şekilde artmaktadır. İHA’ların doğru bir şekilde görevlerini yerine getirebilmeleri için yer istasyonları ile devamlı olarak haberleşmelerini sürdürebilmeleri gerekir. WiFi kablosuz haberleşme metodu yüksek bant genişliği nedeni ile kullanımı artmıştır. Bu haberleşme tipini tehdit edebilecek en önemli tehditlerden biri Hizmet Reddi (DoS) saldırılarıdır. Bu tip bir saldırı durumunda İHA ulaşılmaz olur ve düşebilir. Özellikle açık port numarasının bilinme surumun da dronun kaynaklarını tüketecek ataklar gerçekleştirmek çok daha kolay hale gelir. Bu tehlikeyi gidermek veya en azından hafifletmek amacıyla bu çalışmada bir mekanizma öneriyoruz. Bu mekanizma kablosuz haberleşme (WiFi) kullanan İHA'ların TCP kullanarak gerçekleştiği haberleşmeyi arabir yazılım (middleware) kullanılarak UDP üzerinden yapmasını sağlar. Ayrıca UDP açık portlarını iki tarafın bildiği gizli bir port numarası dizilimi ile periyodik olarak değiştirerek saldırganın açık portu bulması durumda uzun süre kullanımını engeller ve saldırıyı etkisiz kılar. Bu çalışmada port atlatma (port hopping) metodunun İHA’lar üzerine uygulamasını ve etkilerini incelenmesini gerçekleştireceğiz. Gerçek sistemler üzerinde yaptığımız testler önerdiğimiz sistemin İHA’ların haberleşme sistemini %90 kadar daha fazla DoS ataklarına dayanıklı kıldığını gösterdi.

Ageing is the single greatest cause of disease and death worldwide, and understanding the associated processes could vastly improve quality of life. Although major categories of ageing damage have been identified—such as altered intercellular communication, loss of proteostasis and eroded mitochondrial function1—these deleterious processes interact with extraordinary complexity within and between organs, and a comprehensive, whole-organism analysis of ageing dynamics has been lacking. Here we performed bulk RNA sequencing of 17 organs and plasma proteomics at 10 ages across the lifespan of Mus musculus, and integrated these findings with data from the accompanying Tabula Muris Senis2—or ‘Mouse Ageing Cell Atlas’—which follows on from the original Tabula Muris3. We reveal linear and nonlinear shifts in gene expression during ageing, with the associated genes clustered in consistent trajectory groups with coherent biological functions—including extracellular matrix regulation, unfolded protein binding, mitochondrial function, and inflammatory and immune response. Notably, these gene sets show similar expression across tissues, differing only in the amplitude and the age of onset of expression. Widespread activation of immune cells is especially pronounced, and is first detectable in white adipose depots during middle age. Single-cell RNA sequencing confirms the accumulation of T cells and B cells in adipose tissue—including plasma cells that express immunoglobulin J—which also accrue concurrently across diverse organs. Finally, we show how gene expression shifts in distinct tissues are highly correlated with corresponding protein levels in plasma, thus potentially contributing to the ageing of the systemic circulation. Together, these data demonstrate a similar yet asynchronous inter- and intra-organ progression of ageing, providing a foundation from which to track systemic sources of declining health at old age. Bulk RNA sequencing of organs and plasma proteomics at different ages across the mouse lifespan is integrated with data from the Tabula Muris Senis, a transcriptomic atlas of ageing mouse tissues, to describe organ-specific changes in gene expression during ageing.

In this study a system has been developed to detect the human density of indoor spaces such as libraries banks shopping malls. The RGB images used in this work was obtained from the real-life space. First and second order color moments were used as feature extractor. © 2018 IEEE.

The increasing penetration of distributed power generation into the power distribution domain necessitates reliable and QoS-aware communication in order to safely manage the grid. The management of this complex cyber-physical system, called the Smart Grid (SG), requires responsive, scalable and high-bandwidth communication, which is often beyond the capabilities of the classical closed communication networks of the power grid. Consequently, the use of scalable public IP-based networks is increasingly being advocated. However, a direct consequence of the use of public networks is the exposure of the SG to varied reliability/security risks. In particular, the current Internet infrastructure does not support end-to-end (E2E) QoS-guaranteed communication. Furthermore, public networks' more open structure versus proprietary networks potentially exposes the SG to cyberattacks such as Denial-of-Service (DoS) and Distributed DoS (DDoS) which can compromise the high availability and responsiveness of the SG applications. Thus, there is need for new lightweight mechanisms that can provide both E2E communication guarantees along with strong DoS/DDoS attack protection. To address this requirement, we first propose an overlay network based approach. This approach provides a QoS guarantee across the network with a dedicated QoS routing mechanism taking into account three parameters: reliability, latency and bandwidth for SG applications. To achieve the QoS guarantee, we also develop two additional mechanisms: (a) a multipath routing scheme that satisfies the critical applications' high reliability requirements by employing E2E physically-disjoint paths, and (b) an altruistic resource allocation scheme with the QoS routing mechanism targeting QoS-guaranteed communication for applications having strict QoS requirements. Second, we propose a novel DDoS defense mechanism which leverages: (1) a semi-trusted P2P-based publish-subscribe (pub-sub) system providing a proactive countermeasure for DoS/DDoS attacks and secure group communications by aid of a group key management system, (2) a data diffusion mechanism that spreads the data packets over all the servers versus a single server to provide a robust protection against volume-based DDoS attacks that would affect some of the servers, and (3) a multi-homing-based fast recovery mechanism for detecting and requesting the dropped packets, thus paving the way for meeting the stringent latency requirements of SG applications. Third, we develop a cloud-assisted DDoS attack resilient communication platform, built on the proposed defense mechanism discussed above. To prevent transport or application layer DDoS attacks, this platform implements a port hopping approach, switching the open port of a server over a function of both time and a secret (shared between authorized clients and server), thus efficiently dropping packets with invalid port number. By leveraging the rapid-elasticity characteristic of the cloud, we can instantiate replica servers to take over the attacked servers without blocking the all traffic due to the data diffusion mechanism. Moreover, we propose a shuffling-based containment mechanism in order to quarantine malicious clients, which can mount a DDoS attack, exploiting the shared secret in a remarkably short time. Accordingly, the effect of a DDoS attack based on the compromised secret of the malicious clients is minimized. Finally, to counter the transport and application layer DoS/DDoS attacks which are launched by compromised SG devices, we propose a proactive and robust extension of the Multipath-TCP (MPTCP) that mitigates such attacks by using a novel stream hopping MPTCP mechanism, termed MPTCP-H. Unlike the port hopping mechanism, MPTCP-H does not need a shared secret and time-sync between the clients. The proposed MPTCP-H hides the open port numbers of the connection from an attacker by renewing (over time) the subflows over new port numbers without perturbing the SG data traffic. Our results demonstrate that both in the attack and attack-free scenarios, the proposed mechanisms provide a significant availability degree. The results also indicate a reasonable overhead in terms of additional latency and message for the proposed approaches.