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  • Author: López-García J x
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G. Durán-Meza, J. López-García and J.L. del Río-Correa

Abstract

In this work is presented a pedagogical point of view of multifractal analysis deoxyribonucleic acid (DNA) sequences is presented. The DNA sequences are formed by 4 nucleotides (adenine, cytosine, guanine, and tymine). Following Jeffrey’s paper we associated a simple contractive function to each nucleotide, and constructed the Hutchinson’s operator W, which was used to build covers of different sizes of the unitary square Q, thus Wk(Q) is a cover of Q, conformed by 4k squares Qk of size 2−k, as each Qk corresponds to a unique subsequence of nucleotides with length k : b 1 b 2 ...bk. Besides, it is obtained the optimal cover Ck to the fractal F generated for each DNA sequence was obtained. We made a multifractal decomposition of Ck in terms of the sets Jα conformed by the Qk’s with the same value of the Holder exponent α, and determined f (α), the Hausdorff dimension of Jα, using the curdling theorem.

Open access

Del Río-Correa J.L., López-García J. and Durán-Meza G.

Abstract

We extend the Boltzmann’s ideas that describe the evolution to the equilibrium of many body systems to the multifractal decomposition of the unitary interval 𝕀, in terms of sets Jα conformed by points with the same pointwise dimension, and obtain the D(α) singularity spectrum.

Open access

J. Arece-García, Y. López-Leyva, A. Olmedo-Juárez, G. Ramírez-Vargas, D. Reyes-Guerrero, Ma. E. López Arellano, P. Mendoza De Gives, M. Várady, R. Rojo-Rubio and R. González-Garduño

Summary

This study determined the efficacies of four classes of anthelmintics (AH) in a goat flock where anthelmintic resistance (AR) to ivermectin was suspected. We selected and randomly distributed 105 animals with >500 eggs per gram of feces into seven groups of 15 animals: an untreated control group and groups treated with ivermectin, eprinomectin, albendazole sulfoxide, albendazole, levamisole, and closantel. The goats were individually weighed and treated with the recommended dose. Fecal samples were collected 14 days post-treatment to determine the fecal egg counts and for a fecal egg count reduction test (FECRT). Coprocultures were also performed for identifying any resistant genera. A molecular assay (polymerase chain reaction, PCR) was used to confirm benzimidazole resistance. The FECRTs for the ivermectin, eprinomectin, albendazole sulfoxide, and albendazole treatments were <90 %, indicating multiple anthelmintic resistance, all in Haemonchus spp. Levamisole had a FECRT confidence interval <90 %, indicating a moderate level of AR. The PCR detected the ß-tubulin alleles responsible for benzimidazole resistance, confirming AR. This study is the first monospecific report of AR in goats in Cuba, with a total failure of macrocyclic lactones anthelmintic class.

Open access

Roberto González-Garduño, María E. López Arellano, Pedro Mendoza de Gives, Javier Arece García, Carine Marie-Magdeleine, Glafiro Torres Hernández, Jorge Oliva Hernández and J. Alfonso Hinojosa-Cuéllar

Abstract

This study determined the immunoglobulin (A and G) activity against gastrointestinal nematodes (GIN) and also the hematological parameters in four beef-calf breeds naturally infected in a tropical region of Mexico. Thirty-six infected calves were used to determine the fecal nematode egg counts (FEC), the IgA and IgG activity in serum and saliva, the packed cell volume (PCV), the plasmatic protein (PP) and the differential leukocyte counts. These parameters were measured for a five-month period. ELISA assay was performed using adult worm crude antigen (AWCA) from Haemonchus contortus, Trichostrongylus colubriformis, Mecistocirrus digitatus and Cooperia punctata. The variables were analyzed using a fixed model according to the breed group. The FEC records (means ± standard deviation) for the different breeds were: Brangus (122±115), Charolais (391±507), Guzerat (294±326) and Brown Swiss (413±395). No statistical differences (P>0.05) were found among breeds. Cooperia and Haemonchus were the main identified genera in the coprocultures. Differences in hematological parameters were observed among breeds (P<0.01); Guzerat showed the highest PCV (42.6±4.7%). The lowest leukocyte counts were observed in the Charolais breed (9.2±2.4 × 109 cells L-1). Differences between Guzerat and Charolais were only detected in eosinophils, neutrophils and lymphocytes. Increased activity of IgA was observed against M. digitatus (21% OD) compared with the response against C. punctata in serum samples (13% OD). The lowest IgA activity in serum and saliva was found in Guzerat calves. Charolais and Brown Swiss showed the highest IgA activity in serum and the highest value in saliva was found in Brangus.