Santiago Herrera - Academia.edu (original) (raw)
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Papers by Santiago Herrera
Anthozoans (e.g., corals, anemones) are an ecologically important and diverse group of marine met... more Anthozoans (e.g., corals, anemones) are an ecologically important and diverse group of marine metazoans that occur from shallow to deep waters worldwide. However, our understanding of the evolutionary relationships among the ~7500 species within this class is hindered by the lack of phylogenetically informative markers that can be reliably sequenced across a diversity of taxa. We designed and tested 16,308 RNA baits to capture 720 Ultraconserved Element loci and 1,071 exon loci. Library preparation and target enrichment was performed on 33 taxa from all orders within the class Anthozoa. Following Illumina sequencing and Trinity assembly, we recovered 1,774 of 1,791 targeted loci. The mean number of loci recovered from each species was 638 ± 222, with more loci recovered from octocorals (783 ± 138 loci) than hexacorals (475 ± 187 loci). Phylogenetically informative sites ranged from 26-49% for alignments at differing hierarchical taxonomic levels (e.g., Anthozoa, Octocorallia, Hexaco...
Background Attention to the deep-sea environment has increased dramatically in the last decade du... more Background Attention to the deep-sea environment has increased dramatically in the last decade due to the rising interest in natural resource exploitation. Although Colombia holds a large submerged territory, knowledge of the seabed and its biodiversity beyond 1,000 m depth is very limited. During 2015-2017, Anadarko Colombia Company (ACC) carried out hydrocarbon exploratory activities in the Southwestern Colombian Caribbean, at depths between 375 m and 2,565 m.
This paper gauges efficiency in container ports. Using non-parametric methods, we estimate effici... more This paper gauges efficiency in container ports. Using non-parametric methods, we estimate efficiency frontiers based on information from 86 ports across the world. Three attractive features of the method are: 1) it is based on an aggregated measure of efficiency despite the existence of multiple inputs; 2) it does not assume particular input-output functional relationships; and 3) it does not rely on a-priori peer selection to construct the benchmark. Results show that the most ine_cient ports use inputs in excess of 20 to 40 percent. Since infrastructure costs represent about 40 percent of total maritime transport costs, these could be reduced by 12 percent by moving from the inefficient extreme of the distribution to the efficiency one.
These is the Chapther 4 of a Doctoral Thesis in Theology, that speak about the conception of Tho... more These is the Chapther 4 of a Doctoral Thesis in Theology, that speak about the conception of Thomas Aquinas about the Chrurc.
Anthozoans (e.g., corals, anemones) are an ecologically important and diverse group of marine met... more Anthozoans (e.g., corals, anemones) are an ecologically important and diverse group of marine metazoans that occur from shallow to deep waters worldwide. However, our understanding of the evolutionary relationships among the ~7500 species within this class is hindered by the lack of phylogenetically informative markers that can be reliably sequenced across a diversity of taxa. We designed and tested 16,308 RNA baits to capture 720 Ultraconserved Element loci and 1,071 exon loci. Library preparation and target enrichment was performed on 33 taxa from all orders within the class Anthozoa. Following Illumina sequencing and Trinity assembly, we recovered 1,774 of 1,791 targeted loci. The mean number of loci recovered from each species was 638 ± 222, with more loci recovered from octocorals (783 ± 138 loci) than hexacorals (475 ± 187 loci). Phylogenetically informative sites ranged from 26-49% for alignments at differing hierarchical taxonomic levels (e.g., Anthozoa, Octocorallia, Hexaco...
Background Attention to the deep-sea environment has increased dramatically in the last decade du... more Background Attention to the deep-sea environment has increased dramatically in the last decade due to the rising interest in natural resource exploitation. Although Colombia holds a large submerged territory, knowledge of the seabed and its biodiversity beyond 1,000 m depth is very limited. During 2015-2017, Anadarko Colombia Company (ACC) carried out hydrocarbon exploratory activities in the Southwestern Colombian Caribbean, at depths between 375 m and 2,565 m.
This paper gauges efficiency in container ports. Using non-parametric methods, we estimate effici... more This paper gauges efficiency in container ports. Using non-parametric methods, we estimate efficiency frontiers based on information from 86 ports across the world. Three attractive features of the method are: 1) it is based on an aggregated measure of efficiency despite the existence of multiple inputs; 2) it does not assume particular input-output functional relationships; and 3) it does not rely on a-priori peer selection to construct the benchmark. Results show that the most ine_cient ports use inputs in excess of 20 to 40 percent. Since infrastructure costs represent about 40 percent of total maritime transport costs, these could be reduced by 12 percent by moving from the inefficient extreme of the distribution to the efficiency one.
These is the Chapther 4 of a Doctoral Thesis in Theology, that speak about the conception of Tho... more These is the Chapther 4 of a Doctoral Thesis in Theology, that speak about the conception of Thomas Aquinas about the Chrurc.