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Microglial calcium signaling is rare in a baseline state but strongly engaged during early epilepsy development. The mechanism(s) governing microglial calcium signaling are not known. By developing an in vivo uridine diphosphate (UDP) fluorescent sensor, GRAB UDP1.0 , we discovered that UDP release is a conserved response to seizures and excitotoxicity across brain regions. UDP can signal through the microglial-enriched P2Y 6 receptor to increase calcium activity during epileptogenesis. P2Y 6 calcium activity is associated with lysosome biogenesis and enhanced production of NF-κB-related cytokines. In the hippocampus, knockout of the P2Y 6 receptor prevents microglia from fully engulfing neurons. Attenuating microglial calcium signaling through calcium extruder ("CalEx") expression recapitulates multiple features of P2Y 6 knockout, including reduced lysosome biogenesis and phagocytic interactions. Ultimately, P2Y 6 knockout mice retain more CA3 neurons and better cognitive task performance during epileptogenesis. Our results demonstrate that P2Y 6 signaling impacts multiple aspects of myeloid cell immune function during epileptogenesis. [Display omitted] • A UDP1.0 sensor reports enhanced UDP release following hyperexcitability • UDP-P2Y 6 signaling transduces microglial calcium activity in epileptogenesis • P2Y 6 signaling enhances lysosome biogenesis and inflammatory cytokine production • Preventing P2Y 6 signaling preserves neurons and cognition Umpierre, Li, et al. demonstrate that post-seizure UDP release can activate microglial calcium activity through the P2Y 6 receptor. UDP-P2Y 6 signaling engages multiple aspects of immune function during early epilepsy development, including engulfment of neuronal somata and pro-inflammatory cytokine production. P2Y 6 deficiency attenuates pyramidal cell loss and cognitive impairment. [ABSTRACT FROM AUTHOR]

Background: P2Y purinergic receptors (P2YR) are G protein-coupled receptors that are stimulated by extracellular nucleotides. They mediate cellular effects by regulating cAMP production, protein kinase C activation, inositol trisphosphate generation, and Ca2+ release from intracellular stores. The P2Y6 receptor of this family is selectively stimulated by UDP, and selectively inhibited by MRS2578. In the present study, we examined the effect of UDP/P2Y6 receptor signaling on IgE-dependent degranulation in human basophils. Methods: Basophils were purified from human peripheral blood. The mRNA expression of genes encoding P2YR and ecto-nucleoside triphosphate diphosphohydrolase (ENTPDase) was measured by RT-PCR. Intracellular Ca2+ influx via UDP/P2Y6 receptor signaling in basophils was detected using a calcium probe. The effect of UDP/P2Y6 receptor signaling on IgE-dependent degranulation in basophils was confirmed by measuring CD63 expression by flow cytometry. Autocrine secretion of nucleotides was detected by HPLC analysis. Results: We showed that purified basophils express P2Y6 mRNA and that UDP increased intracellular Ca2+, which was reduced by MRS2578 treatment. UDP promoted IgE-dependent degranulation. Furthermore, MRS2578 inhibited IgE-dependent degranulation in basophils. HPLC analysis indicated that basophils spontaneously secrete UTP. In addition, basophils expressed the extracellular nucleotide hydrolases ENTPDase2, ENTPDase3, and ENTPDase8. Conclusions: This study showed that UDP/P2Y6 receptor signaling is involved in the regulation of IgE-dependent degranulation in basophils, which might stimulate the P2Y6 receptor via the autocrine secretion of UTP. Thus, this receptor represents a potential target to regulate IgE-dependent degranulation in basophils during allergic diseases.

A comprehensive experimental study to analyze the security performance of a WLAN based on IEEE 802.11 b/g/n standards in various network scenarios is presented in this paper. By setting-up an experimental testbed we have measured results for a layered security model in terms of throughput, response time, encryption overheads, frame loss and jitter. Through numerical results obtained from the testbed, we have presented quantitative as well as realistic findings for both security mechanisms and network performance. It establishes the fact that there is always a tradeoff between the security strength and the associated network performance. It is observed that the non-roaming network always performs better than the roaming network under all network scenarios. To analyze the benefits offered by a particular security protocol a relative security strength index model is demonstrated. Further we have presented the statistical analysis of our experimental data. We found that different security protocols have different robustness against mobility. By choosing the robust security protocol, network performance can be improved. The presented analysis is significant and useful with reference to the assessment of the suitability of security protocols for given real time application.

Cloud computing, with its staggering and on-demand services had revamped the technology so far. Cloudconsumers are freely to use the applications and software on the premises of Pay-as-you go concept. This concept decreased the cost and make the services less expensive and more reliable. One of the most important characteristic of cloud structure is on demand self-service. Cloud computing applications can be accessed anywhere at any time with much less cost. As cloud provide its consumers with its tremendous on demand services, besides this it is surviving from the excruciating security issues that are discourteous towards the cloud. There are, as many different attacks that results in making the servers down. One of the most hazardous attack is DDoS. This paper hiloghted the DDoS attack and its prevention technique which results in making the server side less vulnerable. The scenario includes, a transmission of million and trillion of packets in the form of DDoS at cloud-based websites, thus making it differentiated though different hosts. Making use of operating systems such as ParrotSec to make the attack possible. Last step includes detection and prevention through the most effective algorithms namely, Naïve Bayes and Random forest. This paper also focused the categories of attacks on cloud computing.

Background: Genome plasticity of Streptococcus pneumoniae is responsible for the reduced efficacy of various antibiotics and capsular polysaccharide-based vaccines. Therefore, targets independent of capsular types are sought to control the pneumococcal pathogenicity. UDP-glucose pyrophosphorylase (UGPase) is one such desired candidate being responsible for the synthesis of UDP-glucose, a sugar precursor in capsular biosynthesis and metabolic Leloir pathway. Being crucial to pneumococcal pathobiology, the effect of UGPase inhibition on virulence was evaluated in vitro. Methods: A putative inhibitor, uridine diphosphate (UDP), was evaluated for effective inhibitory concentration in S. pneumoniae and A549 cells, its efficacy and toxicity. The effect of UDP on adherence and phagocytosis was measured in human respiratory epithelial (A549 and HEp-2) and macrophage (THP1 and J774.A.1) cell lines respectively. Results: A differential effective inhibitory concentration of UDP for UGPase inhibition was observed in S. pneumoniae and A549 cells, that is, 5 and 100 µM respectively. UDP treatments lowered percent cytotoxicity in pneumococcal-infected monolayers and didn't exert adverse effects on viabilities. S. pneumoniae adherence to host cells decreased significantly with UDP treatments. UDP induced the secretion of interleukin (IL)-1ß, tumor necrosis factor (TNF)-a, IL-6, and IL-8 and increased pneumococcal phagocytosis. Conclusion: Our study shows UDP-mediated decrease in the virulence of S. pneumoniae and demonstrates UDP as an effective inhibitor of pneumococcal UGPase. [ABSTRACT FROM AUTHOR]

Flood attacks on a network occur when attackers send a very high volume of traffic to a system. This leads to an exhaustion of resources of the targeted system. Such a system or infrastructure under attack won't be able to cope up with the services it needs to provide due to capacity overload. These types of attacks are also called as Denial of Service (DoS) attacks. As it is essential for companies and organizations to provide high speed and high-quality services the network in which it operates needs to be secured against DoS attacks. As it is said prevention is better than cure, it is always better to detect an attack in the preliminary stages itself and deny an attacker any opportunity to continue the assault on the system. There are various kinds of DoS attacks, in this study the focus is on three kinds of attacks and its detection ICMP flood attack, UDP flood attack and TCP SYN flood attack. The detection mechanism employed is based on packet symmetry which can be used in to monitor the data flow in a network and detect any malicious anomalies in the network traffic at any instant. The experimental results, show that the packet symmetry is a reliable metric to detect attacks on the network by checking the data flow in the ICMP, UDP and TCP layers. [ABSTRACT FROM AUTHOR]

Teleconferencing is the act of meeting and exchanging information through a telecommunication medium. In teleconferencing system, network engineers are faced with different challenges like best protocols requirements; impact of Quality of Service (QoS) to be used to meet up with the latest network protocols and appliances in the design of teleconference system. This paper presented a comparative analysis on two network protocols in a teleconference system, Transmission Control Protocol (TCP) versus a User Datagram Protocol (UDP) was evaluated and compared applying Optimized Network Engineering Tools (OPNET) simulator. The experimental result showed differences in number of videoconference sessions, with few Packet Per Seconds (PPS) recorded in both the UDP and TCP, thereby reflecting the correctness of this comparative evaluation task. [ABSTRACT FROM AUTHOR]

Cloud computing, with its staggering and on-demand services had revamped the technology so far. Cloud consumers are freely to use the applications and software on the premises of Pay-as-you go concept. This concept decreased the cost and make the services less expensive and more reliable. One of the most important characteristic of cloud structure is on demand self-service. Cloud computing applications can be accessed anywhere at any time with much less cost. As cloud provide its consumers with its tremendous on demand services, besides this it is surviving from the excruciating security issues that are discourteous towards the cloud. There are, as many different attacks that results in making the servers down. One of the most hazardous attack is DDoS. This paper hiloghted the DDoS attack and its prevention technique which results in making the server side less vulnerable. The scenario includes, a transmission of million and trillion of packets in the form of DDoS at cloud-based websites, thus making it differentiated though different hosts. Making use of operating systems such as ParrotSec to make the attack possible. Last step includes detection and prevention through the most effective algorithms namely, Naive Bayes and Random forest. This paper also focused the categories of attacks on cloud computing. [ABSTRACT FROM AUTHOR]

Sensors, actuators, and controllers communicate with each other in our Water Management Cyber Physical System (WM-CPS). This WM-CPS is also Internet of Things (IoTs) enable because controllers used in WM-CPS always get a unique IP address during connection with internet. In our work, various communication standards like Ethernet/IP, Modbus/TCP, Modbus/RTU, Wi-Fi 802.11n/IP, Wi-Fi 802.11n/UDP, and Wi-Fi 802.11n/TCP are taken under consideration. Raspberry Pi-3 (RPi-3) board is a controller. Relay and Pump are actuators. Our system works on two layers. Sensors and actuators communicate with controllers on Layer 0 (L0). Controller communicate with data base management system (DBMS), web Interface and virtual private server (VPS) at Layer 1 (L1). We have design and develop web interface of our system available with http://cps4wm.info domain name. This WM-CPS is scalable and able to integrate many more sensors and actuators. We have surveyed 22 communication standards for our future WM-CPS. [ABSTRACT FROM AUTHOR]

The article discusses methods for constructing the transmission of multimodal data in conditions of limited communication channels. The method of transmitting multimodal data using caching repeaters is considered in detail. [ABSTRACT FROM AUTHOR]

The growth in users streaming videos on the Internet has led to increased demand for improved video quality and reception. In next generation networks (NGNs), such as 3G and 4G LTE, quality of service (QoS) implementation is one of the ways in which good video quality and good video reception can be achieved. QoS mainly involves following an industry-wide set of standard metrics and mechanisms to achieve high-quality network performance in respect of video streaming. Adopting routing and communication protocols is one way QoS is implemented in NGNs. This article describes QoS of bit rate video streaming, and QoS performance analysis of video streaming, in relation to the main network transport protocols, namely transmission control protocol (TCP) and user datagram protocol (UDP). A simulation test bed was set up using OPNET modeller 14.5. In this setup, a network topology was created and duplicated three times, in order to configure two simulation scenarios (each using the distinct protocols), and a third simulation scenario using both protocols in hybrid form. The findings in the simulations indicated that, when a network is configured with both TCP and UDP protocols in video streaming, there is a positive change in the degree of performance in terms of the QoS of videostreaming applications, unlike when the protocols are used independently.

Internet is the largest network that transfers a huge amount of information through the web and that requires data transfer between many network bottlenecks, devices and different hardware technologies. This data movement requires data transfer between many application, software’s and operating systems. Many theses and researches were published in the topic of solving the issue of extreme data transfer rate; this issue causes time consuming problems. There are many technologies of transferring data across the internet; two of the major data transfer technologies are the User Datagram Protocol (UDP) and Transmission Control Protocol (TCP). Those different data transfer technologies through the internet cause most of the servers much of their time translating the data from one technology to another because most of the servers deal with one data transfer technology and therefore it has to translate all other technologies to the technology that it deals with. This research establishes a Server named TCP-UDP Server (TUS), to receive data from both UDP and TCP nodes through the same path without the need of changing the network entities or protocols connected to the server and to avoid the need for transferring the data from the (UDP) form to the (TCP) form and vise versa. All the operations performed by the server are accomplished without any hardware intrusion to avoid time consuming. The TUS server as many servers support the multithreading technology to serve a large amount of nodes at the same time. Each node has its own thread to deal with. This thread has its own life time determined by many facts, and that in turn decides to terminate the thread or not.

Abstract O-linked N -acetylglucosamine transferase (OGT) is an essential enzyme that catalyzes the covalent bonding of N -acetylglucosamine (GlcNAc) to the hydroxyl group of a serine or threonine in the target protein. It plays an important role in many important cellular physiological catalytic reactions. Here, we determine the binding mode and the binding free energy of the OGT product (uridine diphosphate, UDP) as well as the hydrogen-bond-dependent release mechanism using extensive molecular dynamic simulations. The Lys634, Asn838, Gln839, Lys842, His901, and Asp925 residues were identified to play a major role in the UDP stabilization in the active site of OGT, where hydrogen bonding and π-π interactions mainly occur. The calculations on the mutant forms support our results. Sixteen possible release channels were identified while the two most favorable channels were determined using random acceleration molecular dynamics (RAMD) simulations combined with the constant velocity pulling (PCV) method. The thermodynamic and dynamic properties as along with the corresponding mechanism were determined and discussed according to the umbrella sampling technique. For the most optimal channel, the main free energy barrier is 13 kcal/mol, which probably originates from the hydrogen bonds between UDP and the Ala896 and Asp925 residues. Moreover, the unstable hydrogen bonds and the rollback of the ligand likely cause the other two small obstacles. This work clarifies the ligand transport mechanism in the OGT enzymatic process and is a great resource for designing inhibitors based on UDP or UDP-GlcNAc. Graphical abstract Unlabelled Image Highlights • Sixteen plausible channels for UDP transportation in OGT are detected. • The key residues that influence the UDP binding and release are identified. • The thermodynamic and dynamic properties for the most two favorable channels of UDP release are obtained. • Hydrogen-bond-dependent product release mechanism in OGT is first revealed. [ABSTRACT FROM AUTHOR]

Viruses are everywhere around us. Not only in our environment but also in virtual environment we are now using on daily basis. To be able to predict their growth it is necessary to understand them or even to develop them. The main problem was how to get rid of any harm in computer or even infrastructure and still be possible to simulate infiltration. Of course it is not an infiltration from real deep point of view. This paper describes how this problem was handled, which type of malware was used, briefly introduces its implementation and also virtual environment this threat was tested. As preferred virtualization tool docker was chosen. Images created in docker and after then run as a containers fit to this work. Alpine was chosen as mini virtual docker image for our purposes. For implementation part C++and a Qt5 framework was utilized to reduce the time with implementation which are already done. Frameworks or OS-es do not provide all important tools and this happened also in this case. Because of that some additional tools has been installed. Most of them are network based tools which are important for this work because this worm implementation communicates over the LAN and communication is on udp based packets. Result of this investigation is fully virtual platform which can be used for testing and improved also for other types of features related to viral usage. [ABSTRACT FROM AUTHOR]

Pervasive computing is an environment which is used and integrated into every object and activities to meet human needs and its existence isn’t perceived as something specific. The concept of Smart Home is to assist human needs in an everyday object that performs controls or being controlled. Based on previous research the used communication protocol is UDP (User Datagram Protocol) and the programming language is LabVIEW. UDP is used because it does not require handshaking in the broadcast process, as well as on the use of memory more efficient than other protocols. Devices which perform controls called Host and which is controlled called Client. Both of them (Things) have an ability to send data to the Internet without any human interaction. So this research wants to conduct pervasive protocol between Host and Client which each device is integrated with the Internet of Things (IoT). Data are posted at dweet.io that is a cloud server website that contains a simple online data submission which has free services. This research is conducted to measure the communication performance between host to client, host to cloud server and client to cloud server that represents household equipment. [ABSTRACT FROM AUTHOR]

Survivability is an issue of great concern in high speed networks. Optical Packet Switching (OPS) is an established technique in the area of survivable high speed future networks. In this paper, network performance is evaluated in response to ingress packet size variation. The performance is evaluated for both protocols: Transmission Control Protocol (TCP) and User Datagram Protocol (UDP). Analysis is performed on mesh networks for different ingress packet size. Response of both transport layer protocols has been observed under single link failure. Network throughput with TCP is higher as compared to throughput with UDP. Network throughput is highest at 500 byte packet size, which is less than the configured Maximum Segment Size (MSS) of transport layer protocols. [ABSTRACT FROM AUTHOR]

Mobile Ad hoc Network (MANET) is a combination of wireless nodes that share resources and information. One of the major issues in MANET is to minimize the energy consumption of wireless nodes. Higher energy consumption nodes minimize the network life while lower energy consumption nodes increase the network life. Various routing protocols have been proposed for energy saving. Ad hoc On-demand Distance Vector (AODV) is an energy efficient routing protocol. In this paper, the energy based performance of AODV routing protocol is evaluated under Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) by using different simulation scenarios. NS2 has been used for simulation purposes. An energy model is defined in which power for receiving and transmitting one packet, initial energy, sleep power, idle power, transition power and transition time values are kept constant for different simulation scenarios. The simulation results show that AODV routing protocol consumes less energy in TCP environment as compared to UDP environment. [ABSTRACT FROM AUTHOR]