On Mobile Bluetooth Tags

This paper presents a new approach for hyper-local data sharing and delivery on the base of discoverable Bluetooth nodes. Our approach allows customers to associate user-defined data with network nodes and use a special mobile application (context-aware browser) for presenting this information to mobile users in proximity. Alternatively, mobile services can request and share local data in M2M applications rely on network proximity. Bluetooth nodes in cars are among the best candidates for the role of the bearing nodes.Comment: submitted to FRUCT-17 conference (http://fruct.org

Twitter as a Transport Layer Platform

Internet messengers and social networks have become an integral part of modern digital life. We have in mind not only the interaction between individual users but also a variety of applications that exist in these applications. Typically, applications for social networks use the universal login system and rely on data from social networks. Also, such applications are likely to get more traction when they are inside of the big social network like Facebook. At the same time, less attention is paid to communication capabilities of social networks. In this paper, we target Twitter as a messaging system at the first hand. We describe the way information systems can use Twitter as a transport layer for own services. Our work introduces a programmable service called 411 for Twitter, which supports user-defined and application-specific commands through tweets.Comment: submitted to Fruct conferenc

PhD

dissertationIn the General Introduction to this Thesis, it was pointed out that the work of previous investigators posed two major problems. The first of these is that of the two "missing" sulfur atoms, and the second, that of the chemical nature of the "active site" of papain. The results of the present investigation provide the answer to the first of these two problems. The investigation of the sulfhydryl content of native, unactivated papain by a number of methods reveals only a fraction of a mole of sulfhydryl per mole of protein. The disulfide interchange reaction clearly indicates the presence of eight groups of papain which, after exposure to 9.6N HC1 at 39°, behave in a manner analogous to the cysteine and cysteine residues in other proteins. In fact, it appears to be reasonable to assume that under the conditions of the interchange reaction, we are dealing with eight half-cystine residues. The determination of the disulfide content of papain by argentimetric amperometric titration with sulfite as the cleaving agent clearly shows the presence of three disulfide bonds in papain at near-neutral pH, whether in the native, urea-denatured, or detergent denatured protein. When papain is exposed to pH 1.7 for a short period of time and then titrated at near-neutral pH in 8M urea, four disulfide bonds may be titrated with silver ion in presence of sulfite. Finally, determination of cysteic acid in acid hydrolysates of papain oxidized with preformic acid clearly shows the presence of eight moles of cysteic acid per mole of papain. The above evidence indicates that after acid treatment or oxidation (which is also performed under acidic conditions), the sulfur content of papain can be accounted for completely on the basis of the half-cystine content of the protein. The answer to the first of the two problems posed above unfortunately has not automatically provided an answer to the second. The studies on the thiol content of active papain in clearly indicate that the activation of papain is associated with the appearance of on thiol group per mole of protein. The hypothesis that activation of papain involves the cleavage of a disulfide bond is subject to a number of serious criticisms. 1. A reductive cleavage of an intramolecular disulfide by column reduction should lead to the appearance of two thiol groups. Actually, Finkle and Smith have shown that only one such group appears as a result of this treatment. This point has been confirmed in the present study. 2. The assumption of an inter-molecular disulfide bond requires the concomitant assumption that inactive papain is a dimer. No evidence for the existence of such a dimer has been found. 3. The fact that acid treatment is required before the fourth disulfide bond can be titrated with silver ion in the presence of sulfite is plausibly explained on the basis of the simple assumption that the denaturation resulting from this treatment renders the bond accessible to sulfite, or changes its environment. The finding that 8M urea at 37° does not bring this about argues against this explanation. In 1958, Smith has suggested that inactive papain exists in an oxidized from, corresponding to the "sulfenic" state. Activation could then be considered as representing reduction to the thiol. This suggestion has received support from the results obtained with the streptococcal proteinase. This enzyme contains only one half-cystine residue per mole. In analogy with papain, the streptococcal proteinase requires activation by thiol compounds. No sulfhydryl can be detected in the inactive enzyme. This situation is clearly best explained by assuming that in the inactive enzyme the sulfhydryl has been oxidized to the -SOH form and that activation consists in the reduction to the sulfhydryl. If we assume that inactive papain does have a sulfenic acid group, the remaining problem is that of its partner - the eight sulfur atom. It is possible that the latter is present in acid-labile covalent linkage, R-S-X, between the half-cystine epsilon-amino group of lysine, an anhydride linkage with a gamma-COOH or a beta-COOH of a glutamic or aspartic acid residue, or an ester linkage between a sulfenic acid and a phenolic hydroxyl group of tyrosine or the -OH group of a serine or threonine residue. The appearance of the fourth disulfide bond after acid treatment could then be interpreted as follows: R-S-X + H+ ?RSH + X+ (1) | RSH + RSOH ? RSSR (2) where R-SOH is the oxidized form of the sulfhydryl involved in the active site of papain. The study of the region of sulfur absorption of proteins in the ultraviolet region, which may have led to the detection of unusual sulfur linkages, is unfortunately greatly complicated by a variety of effects due to other groupings under the conditions necessary for cleavage of acid-labile linkages. The studies on partial acid hydrolysates of oxidized papain have indicated that ac cyteic-cysteic sequence in probably present. Further, the studies on tryptic and chymotryptic hydrolysates of papain, S-carboxymethyl papain and oxidized papain indicate that there is a high concentration of half-cystine residues in some portion of the molecule. A large number of reactions, e.g., dismutations, or reactions such as reaction 2 shown above, which depend on steric factors, could be visualized as being favored by the proximity of the half-cystine residues resulting both from sequential arrangement and the folding of the peptide chain. The ultimate answer to the problem of chemical nature of the "active site" in papain will have to await the determination of the complete amino acid sequence of this protein, The development of specific methods for the demonstration of highly labile linkages in proteins may also be necessary

A Compact Source of Terahertz Radiation Based on an Open Corrugated Waveguide

We show that it is possible to produce terahertz wave generation in an open waveguide, which includes a multilayer dielectric plate. The plate consists of two dielectric layers with a corrugated interface. Near the interface, there is a thin semiconductor layer (quantum well), which is an electron-conducting channel. The generation and amplification of terahertz waves occur due to the efficient energy exchange between electrons, drifting in the quantum well, and the electromagnetic wave of the waveguide. We calculate the inhomogeneous electric fields induced near the corrugated dielectric interface by electric field of fundamental mode in the open waveguide. We formulate hydrodynamic equations and obtain analytical solutions for density waves of electrons interacting with the inhomogeneous electric field of the corrugation. According to numerical estimates, for a structure with a plate of quartz and sapphire layers and silicon-conducting channel, it is possible to generate electromagnetic waves with an output power of 25 mW at a frequency of 1 THz

On Web-based Domain-Specific Language for Internet of Things

This paper discusses the challenges of the Internet of Things programming. Sensing and data gathering from the various sources are often the key elements of applications for Smart Cities. So, the effective programming models for them are very important. In this article, we discuss system software models and solutions, rather than network related aspects. In our paper, we present the web-based domain-specific language for Internet of Things applications. Our goal is to present the modern models for data processing in Internet of Things and Smart Cities applications. In our view, the use of this kind of tools should seriously reduce the time to develop new applications.Comment: submitted to ICUMT 201

Local Messages for Smartphones

This paper describes a new model for local messaging based on the network proximity. We present a novelty mobile mashup which combines Wi-Fi proximity measurements with Cloud Messaging. Our mobile mashup combines passive monitoring for smart phones and cloud based messaging for mobile operational systems. Passive monitoring can determine the location of mobile subscribers (mobile phones, actually) without the active participation of mobile users. This paper describes how to combine the passive monitoring and notifications.Comment: 6 pages. Submitted to CFIC Coimbra 2013 The Conference on Future Internet Communication