Intersection Graph of a Module

Let $V$ be a left $R$-module where $R$ is a (not necessarily commutative) ring with unit. The intersection graph \cG(V) of proper $R$-submodules of $V$ is an undirected graph without loops and multiple edges defined as follows: the vertex set is the set of all proper $R$-submodules of $V,$ and there is an edge between two distinct vertices $U$ and $W$ if and only if $U\cap W\neq 0.$ We study these graphs to relate the combinatorial properties of \cG(V) to the algebraic properties of the $R$-module $V.$ We study connectedness, domination, finiteness, coloring, and planarity for \cG (V). For instance, we find the domination number of \cG (V). We also find the chromatic number of \cG(V) in some cases. Furthermore, we study cycles in \cG(V), and complete subgraphs in \cG (V) determining the structure of $V$ for which \cG(V) is planar

On the critical level-curvature distribution

The parametric motion of energy levels for non-interacting electrons at the Anderson localization critical point is studied by computing the energy level-curvatures for a quasiperiodic ring with twisted boundary conditions. We find a critical distribution which has the universal random matrix theory form ${\bar P}(K)\sim |K|^{-3}$ for large level-curvatures $|K|$ corresponding to quantum diffusion, although overall it is close to approximate log-normal statistics corresponding to localization. The obtained hybrid distribution resembles the critical distribution of the disordered Anderson model and makes a connection to recent experimental data.Comment: 4 pages, 3 figure

An approach for the identification of targets specific to bone metastasis using cancer genes interactome and gene ontology analysis

Metastasis is one of the most enigmatic aspects of cancer pathogenesis and is a major cause of cancer-associated mortality. Secondary bone cancer (SBC) is a complex disease caused by metastasis of tumor cells from their primary site and is characterized by intricate interplay of molecular interactions. Identification of targets for multifactorial diseases such as SBC, the most frequent complication of breast and prostate cancers, is a challenge. Towards achieving our aim of identification of targets specific to SBC, we constructed a 'Cancer Genes Network', a representative protein interactome of cancer genes. Using graph theoretical methods, we obtained a set of key genes that are relevant for generic mechanisms of cancers and have a role in biological essentiality. We also compiled a curated dataset of 391 SBC genes from published literature which serves as a basis of ontological correlates of secondary bone cancer. Building on these results, we implement a strategy based on generic cancer genes, SBC genes and gene ontology enrichment method, to obtain a set of targets that are specific to bone metastasis. Through this study, we present an approach for probing one of the major complications in cancers, namely, metastasis. The results on genes that play generic roles in cancer phenotype, obtained by network analysis of 'Cancer Genes Network', have broader implications in understanding the role of molecular regulators in mechanisms of cancers. Specifically, our study provides a set of potential targets that are of ontological and regulatory relevance to secondary bone cancer.Comment: 54 pages (19 pages main text; 11 Figures; 26 pages of supplementary information). Revised after critical reviews. Accepted for Publication in PLoS ON

Growth and feed utilization in juvenile black sea turbot (Psetta maeotica) under different photoperiod regimes

The effects of 4 different experimental photoperiod regimes, LDN (natural photoperiod), LD24:0 (24 h light:0 h dark), LD12:12 (12 h light: 12 h dark) and LDO:24 (0 h light:24 h dark),. on feed intake and growth parameters of juvenile turbot (21 2.3 g) in the Black Sea were determined. Growth was highest in the group exposed to the continuous photoperiod (LD24:0), followed by the LD12:12, LDN and LDO:24 groups in descending order. The lowest growth rate was recorded in the LDO:24 group. According to the results obtained, LD24:0 and LD12:12 photoperiod exposures are best for better growth and food conversion in juvenile turbot

Changes in blood ion levels and mortality rates in different sized rainbow trout (Oncorhynchus mykiss) following direct transfer to sea water

Plasma ion values and mortality rates were compared for 450 rainbow trout (Oncorhynchus mykiss) of three sizes following direct transfer from fresh water to Black Sea water of about 18 ppt. In fish of 14.29+/-0.30 g, plasma Na+, Cl- and K+ levels significantly (p<0.05) rose above initial values five days after the transfer and peaked at 178.6+/-5.66, 153.9+/-0.14 and 1.14+/-0.04 mM/l, respectively. In 20.45+/-0.48 g fish, these values also rose significantly, reaching 172.4+/-4.24, 151.8+/-6.65 and 0.98+/-0.04 mM/l by day 5. In fish of 29.91+/-0.99 g, however, plasma Na+ and Cl- concentrations peaked 19 days after transfer, reaching only 165.5+/-6.43 and 142.9+/-8.34 mM/l, while plasma K+ reached its highest concentration of 1.02+/-0.06 mM/l on day 12, All three concentrations dropped to near initial values on day 26. In all groups, the plasma Ca2+ level rose significantly (p<0.05) above the initial value five days after transfer and then declined while the plasma P5+ concentration dropped on day 5, reaching a minimum on day 12 and recovering the initial level on day 26. The lowest mortality (8.0+/-1.89%) was recorded in the 30 g group, followed by 19.3+/-0.94% and 24.7+/-0.94% in the 20 g and 14 g groups. The failure of the smallest fish to adapt after direct transfer to sea water was likely due to excessively high plasma Na+ and Cl- concentrations and tissue dehydration, indicating that fish of 30 g best adapt to a seawater environment of 18 ppt

Locally Decodable Codes for Edit Distance

Abstract. Locally decodable codes (LDC) [1,5] are error correcting codes that allow decoding (any) individual symbol of the message, by reading only few symbols of the codeword. Consider an application such as storage solutions for large data, where errors may occur in the disks (or some disks may just crush). In such an application, it is often de-sirable to recover only small portions of the data (have random access). Thus, in such applications, using LDC provides enormous efficiency gains over standard error correcting codes (ECCs), that need to read the en-tire encoded message to learn even a single bit of information. Typically, LDC’s, as well as standard ECC’s decode the encoded messaged if upto some bounded fraction of the symbols had been modified. This corre-sponds to decoding strings of bounded Hamming distance from a valid codeword. An often more realistic metric is the edit distance, measur-ing the shortest sequence of insertions and deletions (indel.) of symbols leading from one word to another. For example, (few) indel. modifica

Using ammonia nitrogen excretion rates as an index for evaluating protein quality of prawns in turbot (Psetta maeotica) nutrition

Total ammonia nitrogen excretion rates were measured in Black Sea turbot (averaging 88.8 g) to compare the protein quality of prawns, the natural food of turbot, with that of the protein source commonly used in the feed industry, i.e. anchovy meal. Two different prawn species (Baltic prawn, Palaemon adspersus, and rockpool prawn, Palaemon elegans) were offered to fish as wet feed at 17.5 +/- 0.5 degrees C and a salinity of 17 ppt. Furthermore, for determination of the effects of wet feed and dry feed on the peak times of ammonia nitrogen excretion rates, another experimental group of fish was offered a commercial dry diet with anchovy meal as a single protein source. The ammonia nitrogen excretion rate in both groups fed prawns peaked 3 h after feeding, while the peak of the excretion rate of fish fed the dry diet was delayed up to 6 h after feeding. Cumulative ammonia nitrogen excretion rates as well as the excretion as a proportion of ingested nitrogen were significantly lower (P < 0.05) in fish fed prawns than those in fish fed the dry diet. Significantly lower excretion levels in the prawn groups might be a reflection of the protein quality of these species, which may be higher than that of the anchovy meal for turbot nutrition

Paying for parking : improving stated-preference surveys

This article describes an experiment which introduced random ranges into the variables used for the design of a stated preference survey and its effects on willingness to pay for parking. User behaviour at the time of parking was modelled to determine their willingness to pay in order to get to their final destination more quickly. Calculating willingness to pay is fundamental during the social and economic assessment of projects. It is important to correctly model how car parks and their users interact in order to get values which represent reality as closely as possible. Willingness to pay is calculated using a stated preference survey and by calibrating multinomial logit models, taking variable tastes into account. It is shown that a value with a low variability can be obtained for willingness to pay by correctly establishing the context of the choice and randomly changing the variables around an average value

Pneumoconiosis and respiratory problems in dental laboratory technicians: Analysis of 893 dental technicians

Objectives: To explore the rate of pneumoconiosis in dental technicians (DTP) and to evaluate the risk factors. Material and Methods: Data of 893 dental technicians, who were admitted to our hospital in the period January 2007–May 2012, from 170 dental laboratories were retrospectively examined. Demographic data, respiratory symptoms, smoking status, work duration, working fields, exposure to sandblasting, physical examination findings, chest radiographs, pulmonary function tests and high-resolution computed tomography results were evaluated. Results: Dental technicians’ pneumoconiosis rate was 10.1% among 893 cases. The disease was more common among males and in those exposed to sandblasting who had 77-fold higher risk of DTP. The highest profusion subcategory was 3/+ (according to the International Labour Organization (ILO) 2011 standards) and the large opacity rate was 13.3%. Conclusions: To the best of our knowledge, it was the largest DTP case series (N = 893/90) in the literature in English. Health screenings should be performed regularly for the early diagnosis of pneumoconiosis, which is an important occupational disease for dental technicians