The problem of assessing the relative calibrations and relative accuracies of a set of p instrume... more The problem of assessing the relative calibrations and relative accuracies of a set of p instruments, each designed to measure the same characteristic on a common group of individuals is considered by using the EM algorithm. As shown, the EM algorithm provides a general solution for this problem. Its implementation is simple and in its most general form requires no extra iterative procedures within the M step. One important feature of the algorithm in this set up is that the error variance estimates are always positive. Thus, it can be seen as a kind of restricted maximization procedure. The expected information matrix for the maximum likelihood estimators is derived, upon which the large sample estimated covariance matrix for the maximum likelihood estimators can be computed. The problem of testing hypothesis about the calibration lines can be approached by using the Wald statistics. The approach is illustrated by re-analysing two data sets in the literature.
The complete internal transcribed spacer 1 (ITS1), 5.8S rDNA, and ITS2 region of the ribosomal DN... more The complete internal transcribed spacer 1 (ITS1), 5.8S rDNA, and ITS2 region of the ribosomal DNA and a 390-bp region of the 16S rDNA gene from five taxa belonging to Rhinonyssus (Rhinonyssus vanellus, Rhinonyssus tringae, Rhinonyssus neglectus, Rhinonyssus echinipes from Kentish plover, and Rhinonyssus echinipes from grey plover) were sequenced to examine the level of sequence variation and the taxonomic levels to show utility in phylogeny estimation. Our data show that these molecular markers can help to discriminate between species and populations included in the Rhinonyssus coniventris complex (R. tringae, R. neglectus, R. echinipes), which are morphologically very close and difficult to separate by classic methods. A comparative study with sequences from other rhinonyssid mites previously published was also carried out. The resulting phylogenetic tree inferred from ITS1–5.8S–ITS2 region sequences obtained in this paper, together with those from other 11 taxa of rhinonyssid, shows slight differences from the current taxonomy of the Rhinonyssidae. This study appeals for the revision of the taxonomic status of the R. coniventris complex, as well as for the species included within it.
Your article is protected by copyright and all rights are held exclusively by Springer-Verlag. Th... more Your article is protected by copyright and all rights are held exclusively by Springer-Verlag. This e-offprint is for personal use only and shall not be self-archived in electronic repositories. If you wish to self-archive your work, please use the accepted author's version for posting to your own website or your institution's repository. You may further deposit the accepted author's version on a funder's repository at a funder's request, provided it is not made publicly available until 12 months after publication.
Trichuris suis was isolated from the cecum of two different hosts (Sus scrofa domestica -- swine ... more Trichuris suis was isolated from the cecum of two different hosts (Sus scrofa domestica -- swine and Sus scrofa scrofa -- wild boar) and Trichuris vulpis from dogs in Sevilla, Spain. Genomic DNA was isolated and internal transcribed spacers (ITS)1-5.8S-ITS2 segment from the ribosomal DNA (rDNA) was amplified and sequenced using polymerase chain reaction techniques. The sequence of T. suis from both hosts was 1,396 bp in length while that of T. vulpis was 1,044 bp. ITS1 of both populations isolated of T. suis was 661 nucleotides in length, while the ITS2 was 534 nucleotides in length. Furthermore, the ITS1 of T. vulpis was 410 nucleotides in length, while the ITS2 was 433 nucleotides in length. One hundred fifty-four nucleotides were observed along the 5.8S gene of T. suis and T. vulpis. Intraindividual and intraspecific variations were detected in the rDNA of both species. The presence of microsatellites was observed in all the individuals assayed. Sequence analysis of the ITSs and the 5.8S gene has demonstrated no sequence differences between T. suis isolated from both hosts (S. scrofa domestica -- swine and S. scrofa scrofa -- wild boar). Nevertheless, clear differences were detected between the ITS1 and ITS2 of T. suis and T. vulpis. Furthermore, a comparative molecular analysis between both species and the previously published ITS1-5.8S-ITS2 sequence data of Trichuris ovis, Trichuris leporis, Trichuris muris, Trichuris arvicolae, and Trichuris skrjabini was carried out. A common homology zone was detected in the ITS1 sequence of all species of trichurids.
A morphobiometrical and molecular study of two populations of Demodex folliculorum from humans is... more A morphobiometrical and molecular study of two populations of Demodex folliculorum from humans isolated from different habitats, skin and eyelashes follicles, were carried out. Morphological and biometrical studies revealed two closely related populations with any distinctive characteristics. For molecular study, a 436-bp region of the 16S rDNA gene and a 453-bp region of the cytochrome oxidase I (COI) gene from individual mites of each population considered were sequenced. Intraindividual and interindividual sequence variation was studied in both populations. Our data show that 16S rDNA is not a useful marker to discriminate between populations; however, COI gene sequences can help to identify the two populations considered, which are morphologically very close and difficult to separate by classic methods. These results are in agreement with the morphological and biometrical differences detected between D. folliculorum from eyelashes and human skin. This study appeals for the revision of the taxonomic status of the D. folliculorum populations, as well as for the species included within genus Demodex.
Trichuris suis was isolated from the cecum of two different hosts (Sus scrofa domestica—swine and... more Trichuris suis was isolated from the cecum of two different hosts (Sus scrofa domestica—swine and Sus scrofa scrofa—wild boar) and Trichuris vulpis from dogs in Sevilla, Spain. Genomic DNA was isolated and internal transcribed spacers (ITS)1-5.8S-ITS2 segment from the ribosomal DNA (rDNA) was amplified and sequenced using polymerase chain reaction techniques. The sequence of T. suis from both hosts was 1,396 bp in length while that of T. vulpis was 1,044 bp. ITS1 of both populations isolated of T. suis was 661 nucleotides in length, while the ITS2 was 534 nucleotides in length. Furthermore, the ITS1 of T. vulpis was 410 nucleotides in length, while the ITS2 was 433 nucleotides in length. One hundred fifty-four nucleotides were observed along the 5.8S gene of T. suis and T. vulpis. Intraindividual and intraspecific variations were detected in the rDNA of both species. The presence of microsatellites was observed in all the individuals assayed. Sequence analysis of the ITSs and the 5.8S gene has demonstrated no sequence differences between T. suis isolated from both hosts (S. scrofa domestica—swine and S. scrofa scrofa—wild boar). Nevertheless, clear differences were detected between the ITS1 and ITS2 of T. suis and T. vulpis. Furthermore, a comparative molecular analysis between both species and the previously published ITS1-5.8S-ITS2 sequence data of Trichuris ovis, Trichuris leporis, Trichuris muris, Trichuris arvicolae, and Trichuris skrjabini was carried out. A common homology zone was detected in the ITS1 sequence of all species of trichurids.
Diario de una ninfómana es el conmovedor relato de una mujer francesa, de buena familia, licencia... more Diario de una ninfómana es el conmovedor relato de una mujer francesa, de buena familia, licenciada en dirección de empresas, que narra su evolución vital a través de las relaciones sexuales que va teniendo: con los sepultureros de un cementerio, con un árabe «muy aficionado» a la Coca-Cola, con un policía sin escrúpulos, con desconocidos en lugares imprevistos... Multitud de vivencias que asume con la máxima libertad que tiene cualquier persona: la que uno se concede a sí mismo y no la que se ve obligado a tener.
The problem of assessing the relative calibrations and relative accuracies of a set of p instrume... more The problem of assessing the relative calibrations and relative accuracies of a set of p instruments, each designed to measure the same characteristic on a common group of individuals is considered by using the EM algorithm. As shown, the EM algorithm provides a general solution for this problem. Its implementation is simple and in its most general form requires no extra iterative procedures within the M step. One important feature of the algorithm in this set up is that the error variance estimates are always positive. Thus, it can be seen as a kind of restricted maximization procedure. The expected information matrix for the maximum likelihood estimators is derived, upon which the large sample estimated covariance matrix for the maximum likelihood estimators can be computed. The problem of testing hypothesis about the calibration lines can be approached by using the Wald statistics. The approach is illustrated by re-analysing two data sets in the literature.
The complete internal transcribed spacer 1 (ITS1), 5.8S rDNA, and ITS2 region of the ribosomal DN... more The complete internal transcribed spacer 1 (ITS1), 5.8S rDNA, and ITS2 region of the ribosomal DNA and a 390-bp region of the 16S rDNA gene from five taxa belonging to Rhinonyssus (Rhinonyssus vanellus, Rhinonyssus tringae, Rhinonyssus neglectus, Rhinonyssus echinipes from Kentish plover, and Rhinonyssus echinipes from grey plover) were sequenced to examine the level of sequence variation and the taxonomic levels to show utility in phylogeny estimation. Our data show that these molecular markers can help to discriminate between species and populations included in the Rhinonyssus coniventris complex (R. tringae, R. neglectus, R. echinipes), which are morphologically very close and difficult to separate by classic methods. A comparative study with sequences from other rhinonyssid mites previously published was also carried out. The resulting phylogenetic tree inferred from ITS1–5.8S–ITS2 region sequences obtained in this paper, together with those from other 11 taxa of rhinonyssid, shows slight differences from the current taxonomy of the Rhinonyssidae. This study appeals for the revision of the taxonomic status of the R. coniventris complex, as well as for the species included within it.
Your article is protected by copyright and all rights are held exclusively by Springer-Verlag. Th... more Your article is protected by copyright and all rights are held exclusively by Springer-Verlag. This e-offprint is for personal use only and shall not be self-archived in electronic repositories. If you wish to self-archive your work, please use the accepted author's version for posting to your own website or your institution's repository. You may further deposit the accepted author's version on a funder's repository at a funder's request, provided it is not made publicly available until 12 months after publication.
Trichuris suis was isolated from the cecum of two different hosts (Sus scrofa domestica -- swine ... more Trichuris suis was isolated from the cecum of two different hosts (Sus scrofa domestica -- swine and Sus scrofa scrofa -- wild boar) and Trichuris vulpis from dogs in Sevilla, Spain. Genomic DNA was isolated and internal transcribed spacers (ITS)1-5.8S-ITS2 segment from the ribosomal DNA (rDNA) was amplified and sequenced using polymerase chain reaction techniques. The sequence of T. suis from both hosts was 1,396 bp in length while that of T. vulpis was 1,044 bp. ITS1 of both populations isolated of T. suis was 661 nucleotides in length, while the ITS2 was 534 nucleotides in length. Furthermore, the ITS1 of T. vulpis was 410 nucleotides in length, while the ITS2 was 433 nucleotides in length. One hundred fifty-four nucleotides were observed along the 5.8S gene of T. suis and T. vulpis. Intraindividual and intraspecific variations were detected in the rDNA of both species. The presence of microsatellites was observed in all the individuals assayed. Sequence analysis of the ITSs and the 5.8S gene has demonstrated no sequence differences between T. suis isolated from both hosts (S. scrofa domestica -- swine and S. scrofa scrofa -- wild boar). Nevertheless, clear differences were detected between the ITS1 and ITS2 of T. suis and T. vulpis. Furthermore, a comparative molecular analysis between both species and the previously published ITS1-5.8S-ITS2 sequence data of Trichuris ovis, Trichuris leporis, Trichuris muris, Trichuris arvicolae, and Trichuris skrjabini was carried out. A common homology zone was detected in the ITS1 sequence of all species of trichurids.
A morphobiometrical and molecular study of two populations of Demodex folliculorum from humans is... more A morphobiometrical and molecular study of two populations of Demodex folliculorum from humans isolated from different habitats, skin and eyelashes follicles, were carried out. Morphological and biometrical studies revealed two closely related populations with any distinctive characteristics. For molecular study, a 436-bp region of the 16S rDNA gene and a 453-bp region of the cytochrome oxidase I (COI) gene from individual mites of each population considered were sequenced. Intraindividual and interindividual sequence variation was studied in both populations. Our data show that 16S rDNA is not a useful marker to discriminate between populations; however, COI gene sequences can help to identify the two populations considered, which are morphologically very close and difficult to separate by classic methods. These results are in agreement with the morphological and biometrical differences detected between D. folliculorum from eyelashes and human skin. This study appeals for the revision of the taxonomic status of the D. folliculorum populations, as well as for the species included within genus Demodex.
Trichuris suis was isolated from the cecum of two different hosts (Sus scrofa domestica—swine and... more Trichuris suis was isolated from the cecum of two different hosts (Sus scrofa domestica—swine and Sus scrofa scrofa—wild boar) and Trichuris vulpis from dogs in Sevilla, Spain. Genomic DNA was isolated and internal transcribed spacers (ITS)1-5.8S-ITS2 segment from the ribosomal DNA (rDNA) was amplified and sequenced using polymerase chain reaction techniques. The sequence of T. suis from both hosts was 1,396 bp in length while that of T. vulpis was 1,044 bp. ITS1 of both populations isolated of T. suis was 661 nucleotides in length, while the ITS2 was 534 nucleotides in length. Furthermore, the ITS1 of T. vulpis was 410 nucleotides in length, while the ITS2 was 433 nucleotides in length. One hundred fifty-four nucleotides were observed along the 5.8S gene of T. suis and T. vulpis. Intraindividual and intraspecific variations were detected in the rDNA of both species. The presence of microsatellites was observed in all the individuals assayed. Sequence analysis of the ITSs and the 5.8S gene has demonstrated no sequence differences between T. suis isolated from both hosts (S. scrofa domestica—swine and S. scrofa scrofa—wild boar). Nevertheless, clear differences were detected between the ITS1 and ITS2 of T. suis and T. vulpis. Furthermore, a comparative molecular analysis between both species and the previously published ITS1-5.8S-ITS2 sequence data of Trichuris ovis, Trichuris leporis, Trichuris muris, Trichuris arvicolae, and Trichuris skrjabini was carried out. A common homology zone was detected in the ITS1 sequence of all species of trichurids.
Diario de una ninfómana es el conmovedor relato de una mujer francesa, de buena familia, licencia... more Diario de una ninfómana es el conmovedor relato de una mujer francesa, de buena familia, licenciada en dirección de empresas, que narra su evolución vital a través de las relaciones sexuales que va teniendo: con los sepultureros de un cementerio, con un árabe «muy aficionado» a la Coca-Cola, con un policía sin escrúpulos, con desconocidos en lugares imprevistos... Multitud de vivencias que asume con la máxima libertad que tiene cualquier persona: la que uno se concede a sí mismo y no la que se ve obligado a tener.
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