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Airborne Ad-hoc Networks (AANETs) are becoming highly popular nowadays. Due to the fast movements of aircraft, there are frequent topology updates which result into a link break between two communicating aircraft. The routing overhead increases multiple times in search of a new route continuously. To deal with this issue of increased overhead, this paper presents a new routing scheme named as Airborne-OLSR (AOLSR). The proposed scheme provides more optimization of Multi-point Relay (MPR) selection criteria used in existing Optimized Link State Routing (OLSR) protocol. This decreases the amount of overhead by selecting the MPR either on the right side or the left side of the source node which depends on the location of the node to which data is to be sent. The decrease in overhead will also result into more bandwidth availability which decreases the possibility of link break. The proposed routing scheme has been compared with the existing OLSR protocol for UDP and TCP environment with varying node speed in 3-D Gauss Markov Mobility model using network simulator-3(ns-3). The simulation analysis shows that the proposed scheme is better in terms of packet delivery ratio, End-to-End delay, routing overhead and throughput as compared to OLSR. We have also compared the AOLSR with previously developed AANET specific protocols like automatic dependent surveillance-broadcast system aided geographic routing protocol(A-GR) and geographic routing protocol for aircraft ad hoc network (GRAA). [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]

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]

As the immunocompetent cells of the central nervous system, microglia accumulate at amyloid beta plaques in Alzheimer's disease (AD) and acquire a morphological phenotype of activated microglia. Recent functional studies, however, indicate that in mouse models of amyloidosis and AD, these cells are rather dysfunctional indicated by a reduced phagocytic activity. Here, we report that this reduction in phagocytic activity is associated with perturbed purinergic receptor signaling, since phagocytosis could be stimulated by P2Y 6 receptor activation in control, but not in 5xFAD transgenic animals, an animal model of amyloid deposition. Impaired phagocytosis is not innate, and develops only at later stages of amyloidosis. Furthermore, we show that membrane currents induced by uridine diphosphate, a ligand activating P2Y 6 receptors, are altered in response rate and amplitude in microglia in close vicinity to plaques, but not in plaque-free areas of 5xFAD animals. These changes were accompanied by changes in membrane properties and potassium channel activity of plaque-associated microglia in early and late stages of amyloidosis. As a conclusion, the physiological properties of plaque-associated microglia are altered with a strong impact on purinergic signaling. [ABSTRACT FROM AUTHOR]

A 1, 8-naphtylimide-based probe 1 was developed for fluorescence sensing of uridine diphosphate (UDP). Probe 1 selectively recognized UDP in solvant system (DMSO-H 2 O) over other structurally similar nucleotides. Among all the tested targets, only the addition of UDP resulted in fluorescence enhancement of about 13-fold. Probe 1 , the first receptor moiety without metal center, could recognize UDP only by multi H-bonds formed between the organic ligand and the base group in nucleotide. Moreover, probe 1 exhibited excellent cell permeability. The fluorescence imaging of UDP by probe 1 in Hela cells and Caenorhabditis elegans ( C. elegans ) demonstrated its potential as a fluorescent sensor for in vivo imaging of UDP. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Forth Generation (4G) network support for wide geographical locations proves its use as a more advanced wireless technology. The Long-Term Evolution (LTE) is a 4G mobile communications standard set by International Communication Union (ITU), specifically ITU Radio communication Sector (ITU-R). At the moment, video traffic and telecommunications grow under the expansion of LTE, which is considered as the actual motivating access technology of 4G network. Throughout the deployment of LTE, various transport protocols are advised and broadly experimented, for instance, TCP, SCTP, DCCP and UDP that may execute differently on 4G networks subject to the network scenarios and parameter settings. Even though the deployment of LTE is swiftly enhanced, there is a lack of performance evaluation of its protocols. Hence, a widespread scrutiny is required for the evaluation of the operation of numerous protocols for high-end applications such as multimedia. Adopting these applications with flexible quality of service constraints with improved usage of resources is a challenging task. In this paper, the output results of different transport protocols for multimedia streaming applications, e.g., video, through extensive simulations are analyzed. The performance of an MPEG-4 video streaming is evaluated using NS-3. The performance metrics used are delay, jitter, throughput, and packet loss. These metrics are evaluated at the base station via TCP, SCTP, DCCP and UDP protocols over the 4G-LTE technology. The obtained results show that the DCCP performs the best in throughput improvement with the minimization of delay and jitter as compared to UDP, TCP, and SCTP. [ABSTRACT FROM AUTHOR]

This paper presents the design and development of a control scheme, for a robot master–slave teleoperation system man–machine interface. The developed system consists of JUPITER XL SCARA robot as a slave manipulator with only the first two links activated, a wireless User Datagram Protocol (UDP) network, and PC as a master controller. The system model parameters identified using the Least-Squares method. A workspace-control system was developed to deals with the problem of position-tracking of bilateral teleoperated two degrees of freedom manipulator, and aid the human operator in driving and controlling the slave robot that performs critical and difficult tasks such as underwater works. A Proportional-Integral-Derivative (PID) and Fuzzy Logic Control (FLC) controllers with different input signals were applied to the system. It was proved experimentally and by simulation on Matlab that the FLC gave a better performance than the PID controller. The two parallel loop subroutine technique proved a great enhancement to the system performance as it decreased the total delay time in the system to almost 25 ms. [ABSTRACT FROM AUTHOR]

Oligodendrocytes are the myelin-forming cells in the CNS. They enwrap axons, thus permitting fast impulse transmission and exerting trophic actions on neurons. Demyelination accompanied by neurological deficit is a rather frequent condition that is not only associated with multiple sclerosis but has been also recognized in several other neurodegenerative diseases, including brain trauma and stroke, Alzheimer's disease and amyotrophic lateral sclerosis. Recently, alterations of myelin function have been also reported in neuropsychiatric diseases, like depression and autism. Highly relevant for therapeutic purposes, oligodendrocyte precursor cells (OPCs) still persist in the adult brain and spinal cord. These cells are normally rather quiescent, but under specific circumstances, they can be stimulated to undergo differentiation and generate mature myelinating oligodendrocytes. Thus, approaches aimed at restoring myelin integrity and at fostering a correct oligodendrocyte function are now viewed as novel therapeutic opportunities for both neurodegenerative and neuropsychiatric diseases. Both OPCs and mature oligodendrocytes express purinergic receptors. For some of these receptors, expression is restricted at specific differentiation stages, suggesting key roles in OPCs maturation and myelination. Some of these receptors are altered under demyelinating conditions, suggesting that their dysregulation may contribute to disease development and could represent adequate new targets for remyelinating therapies. Here, we shall describe the current literature available on all these receptors, with special emphasis on the P2Y-like GPR17 receptor, that represents one of the most studied receptor subtypes in these cells. This article is part of the Special Issue entitled ‘Purines in Neurodegeneration and Neuroregeneration’. [ABSTRACT FROM AUTHOR]

P2Y 6 receptor (P2Y 6 -R) is involved in various physiological and pathophysiological events. With a view to set rules for the design of UDP-based reversible P2Y 6 -R antagonists as potential drugs, we established structure–activity relationship of UDP analogues, bearing modifications at the uracil ring, ribose moiety, and the phosphate chain. For instance, C5-phenyl- or 3-NMe-uridine-5′-α,β-methylene-diphosphonate, 16 and 23 , or lack of 2′-OH, in 12 – 15 , resulted in loss of both agonist and antagonist activity toward hP2Y 6 -R. However, uridylyl phosphosulfate, 19 , selectively inhibited hP2Y 6 -R (IC 50 112 μM) versus P2Y 2 / 4 -Rs. In summary, we have established a comprehensive SAR for hP2Y 6 -R ligands towards the development of hP2Y 6 -R antagonists. [ABSTRACT FROM AUTHOR]

In pattern recognition, feature extraction techniques have been widely employed to reduce the high dimensionality of data. In this paper, we propose a novel algorithm called fuzzy local discriminant embedding (FLDE) based on the unsupervised discriminant projection criterion and fuzzy set theory for image feature extraction and recognition. In the proposed method, a membership degree matrix is firstly calculated using the fuzzy k -nearest neighbor (FKNN) algorithm, and then the membership degree and the label information are incorporated into the definition of the weighted matrices to get the fuzzy local scatter and fuzzy nonlocal scatter. After characterizing the fuzzy nonlocal scatter and the fuzzy local scatter, a concise feature extraction criterion is derived via maximizing the ratio between them. Experimental results on the ORL, FERET, and CMU PIE face databases show the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

The uridine nucleotides uridine-5′-triphosphate (UTP) and uridine-5′-diphosphate (UDP) have previously been identified in media from cultured cells. However, no study to date has demonstrated their presence in brain extracellular fluid (ECF) obtained in vivo. Using a novel method, we now show that UTP and UDP, as well as uridine, are detectable in dialysates of striatal ECF obtained from freely-moving rats. Intraperitoneal (i.p.) administration of uridine or exposure of striatum to depolarizing concentrations of potassium chloride increases extracellular uridine, UTP and UDP, while tetrodotoxin (TTX) decreases their ECF levels. Uridine administration also enhances cholinergic neurotransmission which is accompanied by enhanced brain levels of diacylglycerol (DAG) and inositol trisphosphate (IP 3 ) and blocked by suramin, but not by PPADS (pyridoxalphosphate-6-azophenyl-2′,4′-disulfonic acid) or MRS2578 suggesting a possible mediation of P2Y2 receptors activated by UTP. These observations suggest that uridine, UTP and UDP may function as pyrimidinergic neurotransmitters, and that enhancement of such neurotransmission underlies pharmacologic effects of exogenous uridine on the brain. [ABSTRACT FROM AUTHOR]

Extracellular nucleotides act as inflammatory mediators through activation of multiple purinoceptors. Under inflammatory conditions, the purinergic signalling is affected by various inflammatory mediators. We previously showed that prostaglandin (PG) E 2 suppressed the elevation of intracellular Ca 2+ concentration ([Ca 2+ ]i) stimulated by P2X 4 , P2Y 2 , and P2Y 6 receptors in J774 murine macrophages. In this study, we examined the mechanism of PGE 2 inhibitory effects on P2Y 6 receptor-mediated function in J774 cells. The P2Y 6 receptor agonist UDP induced a sustained elevation of [Ca 2+ ]i by stimulating the phospholipase C (PLC) signalling pathway. PGE 2 inhibited [Ca 2+ ]i elevation and phosphatidylinositol (PI) hydrolysis in a concentration-dependent manner. J774 cells highly expressed the E-type prostanoid 2 (EP2) receptor subtype, a Gs-coupled receptor. PGE 2 and a selective EP2 receptor agonist caused cyclic AMP (cAMP) accumulation in J774 cells. The inhibitory effects of PGE 2 on P2Y 6 receptor-mediated responses were mimicked by the selective EP2 receptor agonist. Although EP2 receptor is linked to adenylyl cyclase activation, PGE 2 -induced inhibition of Ca 2+ response and PI hydrolysis could not be mimicked by a lipophilic cAMP derivative, dibutyryl cAMP, or an adenylyl cyclase activator, forskolin. The inhibition of UDP-induced PLC activation by PGE 2 was not affected by down-regulation of protein kinase C by phorbol-12-myristate-13-acetate treatment. PGE 2 inhibited PLC activation induced by aluminium fluoride, but not by the Ca 2+ -ionophore, ionomycin. Finally, the inhibition of UDP-induced PLC activation by PGE 2 was impaired by Gs knockdown using siRNA. These results suggest that EP2 receptor activation in macrophages negatively controls the G q/11 -PLC signalling through a Gs-mediated, but cAMP-independent signalling mechanism. [ABSTRACT FROM AUTHOR]

A perylene-based probe was developed for uridine diphosphate (UDP) sensing and cell imaging. The probe presented about 4-fold fluorescence enhancement in the presence or absence of 100 equiv UDP. The selectivity toward UDP over other phosphor-containing anions was observed. The selective UDP sensing was speculated to be related to the binding affinities of Zn 2+ ions in sensor with the uridine and phosphate moieties of UDP. Furthermore, this probe was also applied to image of UDP in living cells. [ABSTRACT FROM AUTHOR]

• UDP acts as a danger signal in alcoholic steatohepatitis by activating the P2Y 6 receptor. • The expression of P2Y 6 receptor was significantly increased in EtOH-fed mice and EtOH-induced RAW264.7 cells. • P2Y 6 receptor may promote inflammatory response by mediating Ca2+ influx and then activating p38 MAPK signaling pathway. • Inhibition of P2Y 6 receptor alleviates EtOH-induced inflammatory response and reduces AML-12 cell apoptosis in vitro. Inflammation plays an important role in the progression of alcohol-related liver disease (ALD). UDP-P2Y 6 signaling is involved in many human diseases. The purinergic P2Y 6 receptor, an important regulator of inflammation and phagocytosis, has attracted attention, but its role in alcoholic steatohepatitis remains unclear. Here, we found that P2Y 6 levels were significantly elevated in Kupffer cells in the livers of mice with alcoholic steatohepatitis and ethanol (EtOH)-induced RAW264.7 cells. In this study, mice with alcoholic steatohepatitis were intraperitoneally injected with MRS2578, a specific inhibitor of the P2Y 6 receptor, and P2Y 6 was silenced in EtOH-induced RAW264.7 cells. We found a marked improvement in steatosis and inflammation in the livers of mice with alcoholic steatohepatitis and EtOH-induced RAW264.7 cells. However, P2Y 6 activation in vivo and overexpression in vitro showed contrasting results. In addition, the expression of phospho-p38 mitogen-activated protein kinase (p-p38 MAPK), a phosphorylated protein in the p38 MAPK signaling pathway, was significantly altered after P2Y 6 silencing or overexpression in vitro. P2Y 6 can induce the activation of the p38 MAPK signaling pathway by mediating the calcium influx, whereas inhibition of the expression of P2Y 6 can block the inflammatory process to some extent and thus improve the inflammatory response. The results of this study suggested that targeting P2Y 6 signaling may be a potentially effective strategy for the treatment of alcoholic steatohepatitis. [ABSTRACT FROM AUTHOR]

Abstract: With the increasing trends of mobile interactions, voice authentication applications are in a higher demand, giving rise to new rounds of research activities. Authentication is an important security mechanism that requires the intended communication parties to present valid credentials to the communication network. In a stronger sense, all the involved parties are required to be authenticated to one another (mutual authentication). In the voice authentication technique described in this paper, the voice characteristics of an intended individual wishing to take part in a communication channel will be classified and processed. This involves a low overhead voice authentication scheme, which features equalization and scaling of the voice frequency harmonics. The performance of this system is discussed in a Labview 8.5 visual development environment, following a complete security analysis. [Copyright &y& Elsevier]

Abstract: The use of programmable logic controllers (PLC) for automation of electromechanical processes is an industrial control system technology. It is more and more in use within the fusion community. Traditionally PLC based systems are operated and maintained using proprietary SCADA systems (supervisory control and data acquisition). They are hardly ever integrated with the fusion control and data acquisition systems. An overview of the state of the art in fusion is given in the article. At JET an inhouse “black box protocol” approach has been developed to communicate with any external system via a dedicated http based protocol. However, a PLC usually cannot be modified to implement this special protocol. Hence, a software layer has been developed that interfaces a PLC by implementing the PLC specific communication part on one side and the black box protocol part on the other side. The software is completely data driven i.e. editing the data structure changes the logic accordingly. It can be tested using the web capability of the black box protocol. Multiple PLC types from different vendors are supported, thus multiple protocols to interface the PLC are in use. Depending on the PLC type and available tools it can be necessary to program the PLC accordingly. Wendelstein 7-X uses another approach. For every single PLC a dedicated communication from and to CoDaC is implemented. This communication is projected (programmed) in the PLC and configurable (data driven) on the CoDaC side. The protocol is UDP based and observed via timeout mechanisms. The use of PLCs for Wendelstein 7-X is standardized. Therefore a single implementation on the CoDaC side allows communication with any PLC. Measured data from the PLC is archived in the mass data store. Set points from CoDaC can be visualized from within the PLC visualization environment. A detailed description, discussion and comparison of the JET and W7-X approaches is given. [Copyright &y& Elsevier]

Abstract: P2Y6 nucleotide receptor (P2Y6-R) plays important physiological roles, such as insulin secretion and reduction of intraocular pressure. However, this receptor is still lacking potent and selective agonists to be used as potential drugs. Here, we synthesized uracil nucleotides and dinucleotides, substituted at the C5 and/or Pα position with methoxy and/or borano groups, 18–22. Compound 18A, Rp isomer of 5-OMe-UDP(α-B), is the most potent and P2Y6-R selective agonist currently known (EC50 0.008μM) being 19-fold more potent than UDP and showing no activity at uridine nucleotide receptors, P2Y2- and P2Y4-R. Analogue 18A was highly chemically stable under conditions mimicking gastric juice acidity (t 1/2 =16.9h). It was more stable to hydrolysis by nucleotide pyrophosphatases (NPP1,3) than UDP (15% and 28% hydrolysis by NPP1 and NPP3, respectively, vs 50% and 51% hydrolysis of UDP) and metabolically stable in blood serum (t 1/2 =17 vs 2.4, 11.9, and 21h for UDP, 5-OMe-UDP, and UDP(α-B), respectively). This newly discovered highly potent and physiologically stable P2Y6-R agonist may be of future therapeutic potential. [Copyright &y& Elsevier]

Abstract: This article presents a distributed control mode at high-speed data communication by using UDP datagram based on a dual-port RAM, with the purpose of exploring an efficient, low CPU occupancy, high-speed, reliable and large amounts of data exchange mode. One port of the proposed dual-port RAM mode is connected to local CPU, which can be easily read and write data and the other port is connected to the reading and writing and communication control dedicated logic, which is responsible for organizing, sending, receiving and analyzing UDP datagram and also for completing the tasks of reading and writing dual-port RAM and sending interrupt request to the local processor. This model not only realizes efficient data exchange, but also provides real-time interrupt response mechanism. In this article, it discusses the functional modules required for these functions, describes the composition of the system and the advantages of technical performance. It also analyzes the feasibility of its development, and demonstrates that this model is an advanced, high performance distributed control communication program with great promising. [Copyright &y& Elsevier]

Abstract: The ASDEX Upgrade tokamak experiment is equipped with a versatile discharge monitoring and control system. It allows to develop and use advanced control algorithms to investigate plasma physics under well-defined conditions with the objective of optimising plasma performance. The achievable quality depends on the accuracy with which the plasma state can be reconstructed from measurements under real-time conditions. Today''s advanced algorithms need physics quantities – scalar entities as well as profiles. These are obtained processing huge numbers of raw measurements with complex diagnostic algorithms. Adequate network communication for the resulting signals is crucial to satisfy real-time requirements, especially when several diagnostic systems cooperate in a feedback control loop. Support for the technology of choice, however, is not easily available for all of the diverse, highly specialised diagnostic systems. We give an overview about the methods that have been explored at ASDEX Upgrade for real-time signal transfer. In particular, we investigated reflective shared memory and Ethernet technologies. Our solution strives to combine their strengths. For fast communication on dedicated computing nodes, reflective shared memory is used. For the majority of diagnostic systems producing large data blocks at moderate rates, Ethernet connections with UDP protocol are employed. Following ASDEX Upgrade''s framework concept, a software layer hides the networks used from both diagnostic and control applications. [Copyright &y& Elsevier]

Abstract: Buffers in emerging optical packet routers are expensive resources, and it is expected that they would be able to store at most a few tens of KiloBytes of data in the optical domain. When TCP and real-time (UDP) traffic multiplex at an optical router with such small buffers (less than 50 KB), we recently showed that UDP packet loss can increase with increasing buffer size. This anomalous loss behaviour can negatively impact the investment made in larger buffers and degrade quality of service. In this paper we explore if this anomalous behaviour can be alleviated by dedicating (i.e., pre-allocating) buffers to UDP traffic. Our contributions within this context are two fold. First, we show using extensive simulations that there would seem to be a critical buffer size above which UDP benefits with dedicated buffers that protect it from the aggressive nature of TCP. However, for smaller buffers that are below this critical value, UDP can benefit by time-sharing the buffers with TCP. Second, we develop a simple linear model that quantitatively captures the combined utility of TCP and real-time traffic for shared and dedicated buffers, and propose a method to optimise the buffer split ratio with the objective of maximising the overall network utility. Our study equips designers of optical packet switched networks with quantitative tools to tune their buffer allocation strategies subject to various system parameters such as the ratio of traffic mix and relative weights associated with TCP and UDP traffic. [Copyright &y& Elsevier]

Abstract: In this paper, an efficient feature extraction method named as constrained maximum variance mapping (CMVM) is developed. The proposed algorithm can be viewed as a linear approximation of multi-manifolds learning based approach, which takes the local geometry and manifold labels into account. The CMVM and the original manifold learning based approaches have a point in common that the locality is preserved. Moreover, the CMVM is globally maximizing the distances between different manifolds. After the local scatters have been characterized, the proposed method focuses on developing a linear transformation that can maximize the dissimilarities between all the manifolds under the constraint of locality preserving. Compared to most of the up-to-date manifold learning based methods, this trick makes contribution to pattern classification from two aspects. On the one hand, the local structure in each manifold is still kept; on the other hand, the discriminant information between manifolds can be explored. Finally, FERET face database, CMU PIE face database and USPS handwriting data are all taken to examine the effectiveness and efficiency of the proposed method. Experimental results validate that the proposed approach is superior to other feature extraction methods, such as linear discriminant analysis (LDA), locality preserving projection (LPP), unsupervised discriminant projection (UDP) and maximum variance projection (MVP). [Copyright &y& Elsevier]

Abstract: The phosphate, uracil, and ribose moieties of uracil nucleotides were varied structurally for evaluation of agonist activity at the human P2Y2, P2Y4, and P2Y6 receptors. The 2-thio modification, found previously to enhance P2Y2 receptor potency, could be combined with other favorable modifications to produce novel molecules that exhibit high potencies and receptor selectivities. Phosphonomethylene bridges introduced for stability in analogues of UDP, UTP, and uracil dinucleotides markedly reduced potency. Truncation of dinucleotide agonists of the P2Y2 receptor, in the form of Up4-sugars, indicated that a terminal uracil ring is not essential for moderate potency at this receptor and that specific SAR patterns are observed at this distal end of the molecule. Key compounds reported in this study include 9, α,β-methylene-UDP, a P2Y6 receptor agonist; 30, Up4-phenyl ester and 34, Up4-[1]glucose, selective P2Y2 receptor agonists; dihalomethylene phosphonate analogues 16 and 41, selective P2Y2 receptor agonists; 43, the 2-thio analogue of INS37217 (P1-(uridine-5′)-P4-(2′-deoxycytidine-5′)tetraphosphate), a potent and selective P2Y2 receptor agonist. [Copyright &y& Elsevier]

Abstract: Nucleotides can modify intraocular pressure (IOP). We have tested the ability of uridine-5′-diphosphate, UDP, for modulating IOP in New Zealand white rabbits. Uridine 5′ diphosphate, UDP, reduced IOP by 82.9±2.6% compared to control. Dose-response analysis demonstrated a concentration dependent pattern which presented a pD2 value of 7.57±1.45, equivalent to an EC50 of 26.91 nM. Of all the tested P2 receptor antagonists, suramin, pyridoxalphosphate-6-azophenyl-2, 4-disulfonic acid (PPADS) and Reactive Blue 2 (RB-2), only the last two were able to reverse the action triggered by UDP. Altogether, UDP acting probably on P2Y6 receptors present on the ciliary processes, can reduce intraocular pressure, indicating that this substance may be used for the treatment of ocular hypertension and glaucoma. [Copyright &y& Elsevier]

Abstract: Data acquisition in shot-based fusion experiments is characterized by a large amount of data collected within a short time. The stellarator experiment Wendelstein 7-X (W7-X) will produce a considerable higher amount of data in a continuous and steady-state operation within half an hour. Therefore, it is not sufficient to wait until all data has been acquired and stored in the database before being able to view and analyze data. Continuous and robust data transport is needed for (1) a distributed data monitoring system to visualize trends, (2) continuous data acquisition of data available at the network and (3) message signaling. The paper introduces a network channel concept covering a system-wide available data description, half sync/half async communication pattern, data serialization, identification and matching of data. It is focusing on the IP Multicast/UDP implementation for the data monitoring system and presents results of performance measurements. Suitability and limitations are discussed and an appropriate answer to the question “When is IP Multicast/UDP reliable?” is given. [Copyright &y& Elsevier]

Abstract: Montelukast and pranlukast are orally active leukotriene receptor antagonists selective for the CysLT1 receptor. Conversely, the hP2Y1,2,4,6,11,12,13,14 receptors represent a large family of GPCRs responding to either adenine or uracil nucleotides, or to sugar-nucleotides. Montelukast and pranlukast were found to inhibit nucleotide-induced calcium mobilization in a human monocyte-macrophage like cell line, DMSO-differentiated U937 (dU937). Montelukast and pranlukast inhibited the effects of UTP with IC50 values of 7.7 and 4.3μM, respectively, and inhibited the effects of UDP with IC50 values of 4.5 and 1.6μM, respectively, in an insurmountable manner. Furthermore, ligand binding studies using [3H]LTD4 excluded the possibility of orthosteric nucleotide binding to the CysLT1 receptor. dU937 cells were shown to express P2Y2, P2Y4, P2Y6, P2Y11, P2Y13 and P2Y14 receptors. Therefore, these antagonists were studied functionally in a heterologous expression system for the human P2Y receptors. In 1321N1 astrocytoma cells stably expressing human P2Y1,2,4,6 receptors, CysLT1 antagonists inhibited both the P2Y agonist-induced activation of phospholipase C and intracellular Ca2+ mobilization. IC50 values at P2Y1 and P2Y6 receptors were <1μM. In control astrocytoma cells expressing an endogenous M3 muscarinic receptor, 10μM montelukast had no effect on the carbachol-induced rise in intracellular Ca2+. These data demonstrated that CysLT1 receptor antagonists interact functionally with signaling pathways of P2Y receptors, and this should foster the study of possible implications for the clinical use of these compounds in asthma or in other inflammatory conditions. [Copyright &y& Elsevier]