Reaching Approximate Byzantine Consensus with Multi-hop Communication

We address the problem of reaching consensus in the presence of Byzantine faults. In particular, we are interested in investigating the impact of messages relay on the network connectivity for a correct iterative approximate Byzantine consensus algorithm to exist. The network is modeled by a simple directed graph. We assume a node can send messages to another node that is up to $l$ hops away via forwarding by the intermediate nodes on the routes, where $l\in \mathbb{N}$ is a natural number. We characterize the necessary and sufficient topological conditions on the network structure. The tight conditions we found are consistent with the tight conditions identified for $l=1$, where only local communication is allowed, and are strictly weaker for $l>1$. Let $l^*$ denote the length of a longest path in the given network. For $l\ge l^*$ and undirected graphs, our conditions hold if and only if $n\ge 3f+1$ and the node-connectivity of the given graph is at least $2f+1$ , where $n$ is the total number of nodes and $f$ is the maximal number of Byzantine nodes; and for $l\ge l^*$ and directed graphs, our conditions is equivalent to the tight condition found for exact Byzantine consensus. Our sufficiency is shown by constructing a correct algorithm, wherein the trim function is constructed based on investigating a newly introduced minimal messages cover property. The trim function proposed also works over multi-graphs.Comment: 24 pages, 1 figure. arXiv admin note: text overlap with arXiv:1203.188

UTUKKŪ LEMNŪTU (UDUG-HUL) IN A NEW TEXT FROM THE IRAQ MUSEUM

A small tablet fragment acquired by the Iraq Museum raises interesting questions, although at first it appeared to be a simple duplicate manuscript from the large bilingual incantation series Udug-hul. Publishing this fragment has drawn attention to an interesting feature of Mesopotamian incantations, in which the āšipu-exorcist protects himself first, before addressing the patient. Although this practice has been known from Tablet 3 of Udug-hul incantations, it turns out that Assur exorcists occasionally inserted their own names into otherwise anonymous incantations and prayers, in order to ensure their own protection, which is a practice not known from other sites

Evaluation of Potential Effect of Menthol Solution on Oral Hygiene Status of Dental Students in a University in Iraq

Purpose: To test the effect of menthol extract on the oral hygiene status of dental students of Faculty of Dentistry, Al- Mustansiriya University, Baghdad, Iraq.Methods: A solution (18 mg %) of menthol was prepared by dissolving menthol crystals in absolute ethanol. Chlorhexidine (CHX, 0.2 %) and deionized water were used as positive and negative controls, respectively. Menthol was examined for its toxic effect. Twenty male albino mice were injected intraperitoneally with a low (10 mg/ml) and high dose (50 mg/ml) of the menthol solution, and acute toxicity (LD50) calculated. A double-blind crossover was designed to test plaque re-growth over 5 days. Thirty male dental student volunteers were asked to cease tooth cleaning and then rinse with 10 ml of menthol solution three times daily for 1.5 min, twice daily with CHX and deionized water. Plaque, gingival and bleeding scores were recorded on days 0 and 5. A washout period of 2 weeks was allowed, and then a new test was initiated. The data obtained were analysed statistically.Results: Menthol mouthwash demonstrates a significant reduction in plaque, gingival and bleeding indices of 0.56, 0.45 and 0.03, respectively. CHX induced a greater reduction in these parameters than menthol with indices of 0.14, 0.26, and 0.04, respectively.Conclusion: Menthol mouth rinse (0.018 %) is an antiplaque and anti-gingivitis agent, though less effective than CHX.Keywords: Menthol mouth rinse, Chlorhexidine, Dental plaque, Gingivitis, Oral hygien

Genetic variants in ALDH1B1 and alcohol dependence risk in a British and Irish population: A bioinformatic and genetic study

Alcohol is metabolized in the liver via the enzymes alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH). Polymorphisms in the genes encoding these enzymes, which are common in East Asian populations, can alter enzyme kinetics and hence the risk of alcohol dependence and its sequelae. One of the most important genetic variants, in this regards, is the single nucleotide polymorphism (SNP) rs671 in ALDH2, the gene encoding the primary acetaldehyde metabolizing enzyme ALDH2. However, the protective allele of rs671 is absent in most Europeans although ALDH1B1, which shares significant sequence homology with ALDH2, contains several, potentially functional, missense SNPs that do occur in European populations. The aims of this study were: (i) to use bioinformatic techniques to characterize the possible effects of selected variants in ALDH1B1 on protein structure and function; and, (ii) to genotype three missense and one stop-gain, protein-altering, non-synonymous SNPs in 1478 alcohol dependent cases and 1254 controls of matched British and Irish ancestry. No significant allelic associations were observed between the three missense SNPs and alcohol dependence risk. The minor allele frequency of rs142427338 (Gln378Ter) was higher in alcohol dependent cases than in controls (allelic P = 0.19, OR = 2.98, [0.62-14.37]) but as this SNP is very rare the study was likely underpowered to detect an association with alcohol dependence risk. This potential association will needs to be further evaluated in other large, independent European populations

Exploring nicotinamide cofactor promiscuity in NAD(P)H-dependent flavin containing monooxygenases (FMOs) using natural variation within the phosphate binding loop. Structure and activity of FMOs from Cellvibrio sp. BR and Pseudomonas stutzeri NF13

Flavin-containing monooxygenases (FMOs) catalyse asymmetric oxidation reactions that have potential for preparative organic synthesis, but most use the more expensive, phosphorylated nicotinamide cofactor NADPH to reduce FAD to FADH2 prior to formation of the (hydro)peroxy intermediate required for substrate oxygenation. A comparison of the structures of NADPH-dependent FMO from Methylophaga aminisulfidivorans (mFMO) and SMFMO from Stenotrophomonas maltophilia, which is able to use both NADPH and NADH, suggested that the promiscuity of the latter enzyme may be due in part to the substitution of an Arg-Thr couple in the NADPH phosphate recognition site in mFMO, for a Gln-His couple in SMFMO (Jensen et al., 2012, Chembiochem, 13, 872-878). Natural variation within the phosphate binding region, and its influence on nicotinamide cofactor promiscuity, was explored through the cloning, expression, characterisation and structural studies of FMOs from Cellvibrio sp. BR (CFMO) and Pseudomonas stutzeri NF13 (PSFMO), which possess Thr-Ser and Gln-Glu in the putative phosphate recognition positions, respectively. CFMO and PSFMO displayed 5- and 1.5-fold greater activity, respectively, than SMFMO for the reduction of FAD with NADH, and were also cofactor promiscuous, displaying a ratio of activity with NADH:NADPH of 1.7:1 and 1:1.3, respectively. The structures of CFMO and PSFMO revealed the context of the phosphate binding loop in each case, and also clarified the structure of the mobile helix-loop-helix motif that appears to shield the FAD-binding pocket from bulk solvent in this class of FMOs, a feature that was absent from the structure of SMFMO

The photoionization dynamics of the three structural isomers of dichloroethene

Using tunable vacuum-UV radiation from a synchrotron, the threshold photoelectron spectrum, threshold photoelectron photoion coincidence spectrum and ion breakdown diagram of the 1,1, cis-1,2 and trans-1,2 isomers of C$_2$H$_2$Cl$_2$ have been recorded in the range 9-23 eV. The energies of the peaks in the threshold photoelectron spectrum are in good agreement with outer-valence Greens function caculations. The major difference between the isomers, both predicted and observed experimentally is that the F and G states of C$_2$H$_2$Cl$_2^+$ are approximately degenerate for 1,1 and trans-1,2, but well separated for the cis-1,2 isomer. The ground and low-lying valence states of C$_2$H$_2$Cl$_2^+$ are bound, with higher-lying states dissociating to C$_2$H$_2$Cl$^+$ or C$_2$H$_2^+$. The translational kinetic energy release into C$_2$H$_2$Cl$^+$ + Cl is determined as a function of energy. Isolated-state behaviour for the low-lying electronic states of C$_2$H$_2$Cl$_2^+$ becomes more statistical as the energy increases

Breeding performance of sustainable fish Ctenopharyngodon idella through single intramuscular injection of Ovaprim-C at Bahawalpur, Pakistan

Effect of intramuscular injection of Ovaprim–C on the number of eggs/kg,  fertilization rate and hatching percentage were studied at a private Fish Hatchery at Bahawalpur, Pakistan, during April to June 2008, on Ctenopharyngodon idella (Grass carp). Studied fish specimens were spawned successfully following a single dose of injection of Ovaprim-C (LH-RH analogue) with 0.6 ml kg-1 for female and 0.2 ml kg-1 for male brooders. Ova and milt were stripped simultaneously and mixture was stirred for 15 to 30 s during which fertilization occurred. Hatching occurred within 18 to 30 h after fertilization. The experiment was conducted in circular spawning tank with 2 m diameter. It was observed that body weight has positive influence on absolute fecundity (r = 0.967), while relative fecundity remained constant with increasing body weight. If it is impossible to determine the absolute and relative fecundity then these parameters can be determined from the body weight.Key words: Induced spawning, Ovaprim-C, fecundity, Ctenopharyngodon idella

Evaluation of Acellular Dermis for Closure of Abdominal Wall Defects in a Rat Model

Background: Abdominal wall repair can be performed with synthetic or biological materials. Biological materials may reduce the risk of infections and fibrosis. The aim of this study was to evaluate two acellular human dermis products. Materials and Methods: A rat model was used to compare the two materials. One was prepared using low concentrations of NaOH; the other material was SureDerm (TM), which is commercially available. Full thickness defects were prepared in the abdominal wall and closed with the materials. Rats were sacrificed at 1 or 4 months after operation and the numbers of adhesions to the bowels were scored. Samples were taken for histological analysis and to measure the breaking strength. Results: In both groups a good functional integration of the implants with the abdominal wall was observed. There was no adhesion formation with the bowels in the group with the NaOH prototype. In the SureDerm group, 4 out of 7 rats showed only small adhesions at 4 months after operation. Breaking strength of the healed tissue was significantly higher in the NaOH prototype group at 4 months after operation (p < 0.0026). Conclusions: The results indicate that both human acellular dermis products may be used in clinical trials for closure of abdominal wall defects

Forward-backward Asymmetry and Branching Ratio of B \rar K_1 \ell^+ \ell^- Transition in Supersymmetric Models

The mass eigen states $K_1(1270)$ and $K_1(1400)$ are mixture of the strange members of two axial-vector SU(3) octet, $^3P_1(K_1^A)$ and $^1P_1(K_1^B)$. Taking into account this mixture, the forward-backward asymmetry and branching ratio of B \rar K_1(1270,1400) \ell^+ \ell^- transitions are studied in the framework of different supersymmetric models. It is found that the results have considerable deviation from the standard model predictions. Any measurement of these physical observables and their comparison with the results obtained in this paper can give useful information about the nature of interactions beyond the standard model.Comment: 14 pages, 4 figure