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Normalização textual e indexação semântica aplicadas da filtragem de SMS spam
(Universidade Federal de São Carlos, 2016-07-01) Silva, Tiago Pasqualini da; Almeida, Tiago Agostinho de; https://lattes.cnpq.br/5368680512020633; https://lattes.cnpq.br/4030198351353056
The rapid popularization of smartphones has contributed to the growth of SMS usage as an alternative way of communication. The increasing number of users, along with the trust they inherently have in their devices, makes SMS messages a propitious environment for spammers. In fact, reports clearly indicate that volume of mobile phone spam is dramatically increasing year by year. SMS spam represents a challenging problem for traditional filtering methods nowadays, since such messages are usually fairly short and normally rife with slangs, idioms, symbols and acronyms that make even tokenization a difficult task. In this scenario, this thesis proposes and then evaluates a method to normalize and expand original short and messy SMS text messages in order to acquire better attributes and enhance the classification performance. The proposed text processing approach is based on lexicography and semantic dictionaries along with the state-of-the-art techniques for semantic analysis and context detection. This technique is used to normalize terms and create new attributes in order to change and expand original text samples aiming to alleviate factors that can degrade the algorithms performance, such as redundancies and inconsistencies. The approach was validated with a public, real and non-encoded dataset along with several established machine learning methods. The experiments were diligently designed to ensure statistically sound results which indicate that the proposed text processing techniques can in fact enhance SMS spam filtering.
Estudos citogenéticos em espécies da família Paradontidae (Actinopterygii: Characiformes), com enfoque no papel dos DNAs repetitivos na evolução cariotípica do grupo
(Universidade Federal de São Carlos, 2016-07-01) Ziemniczak, Kaline; Vicari, Marcelo Ricardo; https://lattes.cnpq.br/9824170107078686; Moreira Filho, Orlando; https://lattes.cnpq.br/3927076022470557; https://lattes.cnpq.br/2382521661695022
Parodontidae is organized in three genera according to their morphological characteristics: Parodon, Saccodon and Apareiodon. The diploid number is conserved in this group with 2n=54 chromosomes, with species without heteromorphic sex chromosomes systems and other with sex chromosomes system, with female heterogamety, ZZ/ZW or ZZ/ZW1W2. Studies of chromosome localization using repetitive DNAs chromosomes of species show possible origin, differentiation and evolution of sex chromosomes in Parodontidae. However, further studies using repeats DNAs are fundamental for a better comprehension of its pathway genomic structural or functional. In this study were described the chromosome location of the (GATA)n and (TTAGGG)n sequences in eight species of Parodontidae, with aim to evaluate the probable mechanisms of chromosomal diversification, especially those related to molecular differentiation of W chromosome. Also were mapped 16 microsatellites sequences in five species of the family to check the accumulation of the repetitive DNAs in the chromosomes and verify its performance in the karyotype and sex chromosomes differentiation. Yet, partial sequences of the histone H1, H3 and H4 were determined and had chromosomal localization in six species of Parodontidae. The data show two H1 sequences in Parodontidae genomes, herein called H1 partial and H1+ ERV, in addition to partial sequences for the genes H3 and H4. The chromosomal localization of histone genes show H1, H3 and H4 in main cluster and the presence of the orphans genes for H1 + ERV. Hence, this study provide some advances in the understanding of the repetitive DNA mechanism in the karyotypic differentiation and evolution in the family Parodontidae.
Obtenção de derivados de compostos isolados de Zingiber officinale por biotransformação e semi-síntese e avaliação frente à cisteinil-proteases
(Universidade Federal de São Carlos, 2016-07-01) Ávila, Roberta Marques Dias de; Vieira, Paulo Cezar; https://lattes.cnpq.br/8923844563320377; https://lattes.cnpq.br/6845823650666405
Several aromatic polyketide derivatives from Ginger (Zingiber officinale), like zingerone, 6-gingerol and 6-shogaol were obtained by biocatalytic reactions and semi-synthesis and both their antifungal and cysteine-proteinase inhibitory properties were investigated. The derivatives obtained by semi-synthesis were evaluated in the form of a first screening for inhibition property of growth of phytopathogenic fungi Colletotrichum gloesporioides and Fusararium oxysparum. The biotransformation of four compounds: zingerone purchased from Sigma Aldrich, 6-gingerol isolated from ginger and its derivatives 4-methyl-6-gingerol and 6-shogaol was investigated using whole cells of C. gloesporioides and showed recognition of the fungal pool of enzymes capable of using such compounds as substrates. All experiments were conducted in sterile liquid medium BD (Potato and Dextrose) under agitation (120 rpm) and constant temperature (30° C ), obtaining the methanol extract of mycelial mass (MM), the aqueous extract (Aq) and the ethyl acetate extract (Ac) of culture fluid. The ethyl acetate extract was analyzed by GC-MS and ESI-MS/MS using LC-MS techniques. The fungus C. gloesporioides proved able to promote a reaction of aromatic oxidative coupling of zingerone, forming a dimer of this molecule. This product was isolated, identified by NMR spectroscopy and high resolution mass spectrometry. The biotransformation experiment was also made with isotopically labeled zingerone with deuterium. Analysis of the ethyl acetate extract (Ac) by (-) ESI-MS / MS using LC-IT-MS showed that dimer formation since the first day once the isotopically labeled fragments were detected. The aromatic oxidative coupling reaction also occurs in the biotransformation to phenolic compound 6-gingerol by C. gloesporioides. It is probable that side chain of 6-gingerol was used as carbon source forming an alcohol with molecular mass 168 Da. The dimer of the alcohol appears as biotransformation product. Among the proposed semi-synthesis reactions, the insertion of an oxime ether subunit from zingerone as starting material was obtained. Despite the molecular modeling indicates good complementarity with the catalytic site model cysteinyl preoteases, the product obtained does not show inhibitory activity against the enzymes L and V to 25 uM. The oximine derivative of 8-gingerol, presented halo of inhibition against the proliferation of fungus C.gloesporioides in disk diffusion test on PDA (Potato Dextrose Agar) in a Petri dish. The ethyl acetate extract (Ac) from the tenth day showed a good result of inhibition of cathepsin V (80%). There are studies that investigate the relationship between the antifungal activity of compounds of the property of inhibiting cysteine-preoteases as papain and cathepsin B and L.
Efeito da rochagem no crescimento e nutrição de plantas de batata
(Universidade Federal de São Carlos, 2016-07) Moreira, Diulie Talita; Soares, Marcio Roberto; https://lattes.cnpq.br/6337462438517339; https://lattes.cnpq.br/3308312287471252
Brazil is considered a country with extreme potential for agricultural production, but with great dependence on fertilizer imports. The Brazilian area with the potato crop is estimated at 130,000 ha. It is a high nutrient-demanding crop that consumes about 1.5 t of fertilizers per ha. An alternative to increase potato quality and productivity and make the production system more sustainable is the application of stonemeal. This study aimed to evaluate the growth and productivity parameters of the potato, Ágata variety, grown under different sources and increasing doses of rock powder. The experiment was carried out under greenhouse conditions, adopting a completely randomized design, with a 5x3 factorial scheme and five replications. The first factor consisted of three different sources of rock powder [mica-schist; blend I (kamafugite + mica-schist); blend II (kamafugite + mica; schist + microorganism source (Amino Peixe Raízes®)]. The second factor was made up of the following doses: 0, 3,000, 4,000, 5,000, 6000 kg ha-1. At the end of the cycle (95 days after planting), the following parameters were analyzed: height and number of stems, number and weight of tubers and productivity. Number of stems per plant did not respond to the application of crushed rocks.The treatment with blend II provided a significant increase in the weight and number of tubers in addition to increasing productivity by 36%. The biological component added in the blend II treatment was determinant in accelerating the availability of rock nutrients during the potato cycle.