Publications by authors named "José E Ortiz"

11 Publications

  • Page 1 of 1

Keys to discern the Phoenician, Punic and Roman mining in a typical coastal environment through the multivariate study of trace element distribution.

Sci Total Environ 2021 Oct 26;790:147986. Epub 2021 May 26.

University of Natural Resources and Applied Life Sciences, Peter Johan Str. 82, 1190 Viena, Austria. Electronic address:

Trace element concentrations in the Cartagena Bay coastal record reveal a contribution of natural processes. However, the influence of anthropogenic factors predominates in the last three millennia, particularly aerosol deposition linked to mining and industrial activities in the area. The coastal record of Cartagena can be considered a preserved environment, suitable to search for regional human activity fingerprinting, specifically that related to the deposition of heavy metals such as Pb and Cu. A multivariate statistical analysis was carried out to clarify the geochemical behaviour of trace and major elements. Our study design represents a novel approach to assign natural contributions, such as eolian and riverine input, to coastal deposits, and organic matter preservation under anoxic environments. Therefore, synergies obtained by the simultaneous study of multivariate statistics and enrichment factors allow robust conclusions about palaeoenvironmental evolution and human activities. Anthropogenic influence suggested that Pb mining and metallurgy began during the Chalcolithic period, with considerable inputs of Pb and Cu to atmospheric pollution during Phoenician, Punic and Roman times.
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http://dx.doi.org/10.1016/j.scitotenv.2021.147986DOI Listing
October 2021

Pasteur made simple - mechanochemical transformation of racemic amino acid crystals into racemic conglomerate crystals.

Chem Commun (Camb) 2020 Apr 23;56(33):4547-4550. Epub 2020 Mar 23.

Departamento de Cristalografia y Mineralogia, Facultad de Geologia, Universidad Complutense, 28040 Madrid, Spain.

Conglomerate crystallization is required for many deracemization or enantioenrichment protocols. Here, we report the metal-mediated mechanochemical transformation of racemic compounds of some proteinogenic amino acids - valine, leucine and isoleucine - into their corresponding conglomerates. Specifically, ZnO has the ability to promote and stabilize the conglomerate phase of these amino acids to an extent where the racemic compound is not observed.
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http://dx.doi.org/10.1039/c9cc10047dDOI Listing
April 2020

A multivariate examination of the timing and accumulation of potentially toxic elements at Las Conchas bog (NW Spain).

Environ Pollut 2019 Nov 12;254(Pt B):113048. Epub 2019 Aug 12.

Biomolecular Stratigraphy Laboratory, E.T.S.I. Minas y Energía, Universidad Politécnica de Madrid, Madrid, 28003, Spain.

The inorganic content of the well-preserved 3.2-m record of Las Conchas bog (NW Spain), covering 8000 cal yr BP., was analysed. To study natural vs. human contributions, we applied an innovative approach, namely the sequential study of multivariate statistics (factor analysis followed by clustering of the factor score matrix) and enrichment factors (EFs). The increasing weight of potentially toxic elements (PTEs) such as the geochemical association of Zn, Pb and Cd (EFs higher than 10, 20 and 40 in the last two centuries) was revealed, and corroborated by the contrast between the contents of anthropogenic Pb and total Rare Earth Elements (a suitable proxy for natural geogenic supplies). Furthermore, elements such as Hg, Tl and As also showed enrichment in the most recent samples of the study core. Some of them are commonly associated with global atmospheric transport; however, in this case, their increasing contents could also be explained by nearby industrial and mining activities. In summary, severe pollution was observed in the uppermost part of the record, thereby pointing to an important environmental concern. Given that local and regional sources of PTEs, such as mining and heavy industry, especially Zn smelting, were probably the main historical causes of this contamination and that some of these industries are still active, we consider that our findings deserve further attention.
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http://dx.doi.org/10.1016/j.envpol.2019.113048DOI Listing
November 2019

Ancient DNA reveals differences in behaviour and sociality between brown bears and extinct cave bears.

Mol Ecol 2016 10 6;25(19):4907-18. Epub 2016 Sep 6.

Institute for Biochemistry and Biology, University of Potsdam, 14476, Potsdam OT Golm, Germany.

Ancient DNA studies have revolutionized the study of extinct species and populations, providing insights on phylogeny, phylogeography, admixture and demographic history. However, inferences on behaviour and sociality have been far less frequent. Here, we investigate the complete mitochondrial genomes of extinct Late Pleistocene cave bears and middle Holocene brown bears that each inhabited multiple geographically proximate caves in northern Spain. In cave bears, we find that, although most caves were occupied simultaneously, each cave almost exclusively contains a unique lineage of closely related haplotypes. This remarkable pattern suggests extreme fidelity to their birth site in cave bears, best described as homing behaviour, and that cave bears formed stable maternal social groups at least for hibernation. In contrast, brown bears do not show any strong association of mitochondrial lineage and cave, suggesting that these two closely related species differed in aspects of their behaviour and sociality. This difference is likely to have contributed to cave bear extinction, which occurred at a time in which competition for caves between bears and humans was likely intense and the ability to rapidly colonize new hibernation sites would have been crucial for the survival of a species so dependent on caves for hibernation as cave bears. Our study demonstrates the potential of ancient DNA to uncover patterns of behaviour and sociality in ancient species and populations, even those that went extinct many tens of thousands of years ago.
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http://dx.doi.org/10.1111/mec.13800DOI Listing
October 2016

[Value of the optical coherence tomography in the treatment guided of the stent failure. Case report].

Arch Cardiol Mex 2014 Oct-Dec;84(4):305-9. Epub 2014 Aug 6.

Departamento de Cardiología Intervencionista, Hospital de Especialidades Dr. Belisario Domínguez, México D.F., México.

Since the advent of bare metal and drug-eluting stents, the surgical revascularization have declined considerably, however the thrombosis and in-stent restenosis are important complications of these devices. There are several factors that predispose to thrombosis and in-stent restenosis. Conventional angiography has serious limitations to determine the causes of stent failure. Optical coherence tomography is a very sensitive technique to determine the cause of thrombosis and in-stent restenosis.
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http://dx.doi.org/10.1016/j.acmx.2014.06.001DOI Listing
November 2015

Multivariate study of trace element distribution in the geological record of Roñanzas Peat Bog (Asturias, N. Spain). Paleoenvironmental evolution and human activities over the last 8000 calyr BP.

Sci Total Environ 2013 Jun 26;454-455:16-29. Epub 2013 Mar 26.

Environmental Biotechnology & Geochemistry Group, Campus de Mieres, Universidad de Oviedo, Spain.

Trace element concentrations in the Roñanzas peat bog record reveal a contribution of natural processes but the influence of anthropogenic factors predominates in the last two millenniums, particularly aerosol deposition linked to mining and industrial activities in northern Spain. We observed that the Roñanzas record can be considered a preserved environment, suitable to search for local (<50 km), regional (50-150 km) and/or long-distance human activity fingerprinting, specifically that related to the deposition of heavy metals such as Pb, Zn and Hg. We also carried out a multivariate statistical study in order to clarify the geochemical behavior of trace and major elements. Our study design represents a novel approach to assign natural vs. human contributions in peatlands. Therefore, synergies obtained by the simultaneous study of multivariate statistics and enrichment factors allow robust conclusions about paleoenvironmental evolution and human activities. Anthropogenic influence has also been reported in similar records in other parts of Europe, thereby suggesting large-scale sources for atmospheric pollution. However, here we revealed remarkable particularities, such as the association of Cd, Zn and Pb, mainly linked to regional and local factors (mining and more recently the metallurgical industry), whereas we propose that the occurrence of Hg is associated with a combination of regional factors and global atmospheric pollution.
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http://dx.doi.org/10.1016/j.scitotenv.2013.02.083DOI Listing
June 2013

Enantioenrichment in sublimed amino acid mixtures.

Chem Commun (Camb) 2012 Apr 2;48(30):3623-5. Epub 2012 Mar 2.

Departamento de Cristalografía y Mineralogía, Facultad de Geología, Universidad Complutense, 28040 Madrid, Spain.

A real amplification of an initial enantiomeric excess can be detected when two amino acids are sublimed at high temperature, even if one of the components is a racemic compound that does not convert into a conglomerate by sublimation.
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http://dx.doi.org/10.1039/c2cc18129kDOI Listing
April 2012

Asymmetric amplification in amino acid sublimation involving racemic compound to conglomerate conversion.

Chem Commun (Camb) 2011 Jan 26;47(2):671-3. Epub 2010 Nov 26.

Departamento de Cristalografía y Mineralogía, Facultad de Geología, Universidad Complutense, 28040 Madrid, Spain.

A straightforward unprecedented sublimation protocol that reveals both conversion of a racemic compound into a racemic conglomerate and subsequent enantioenrichment has been developed for the proteinogenic amino acid valine. The phenomenon has been observed in closed and open systems, providing insight into asymmetric amplification mechanisms under presumably prebiotic conditions.
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http://dx.doi.org/10.1039/c0cc04271dDOI Listing
January 2011

Solution-phase racemization in the presence of an enantiopure solid phase.

Chemistry 2010 Apr;16(16):4932-7

Departamento Cristalografia-Mineralogia, Facultad Geologia, Universidad Complutense, 28040 Madrid, Spain.

Solution-phase racemization drives the evolution of single chirality in the solid phase by the "chiral amnesia" process first described by Viedma. The current investigations lay the basis for a better understanding of the mechanism of the solid-phase deracemization by uncoupling the chemical rate processes associated with the interconversion of enantiomers in the solution phase from the physical processes associated with solution-solid phase transfer via dissolution and reaccretion of molecules onto crystals. In addition, the enantiomer concentration profiles presented in this work, together with an analytical treatment of the racemization process in the presence of excess enantiopure solid, unequivocally reconfirm the validity of the Meyerhoffer double solubility rule for systems under solution racemization conditions.
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http://dx.doi.org/10.1002/chem.200902983DOI Listing
April 2010

Evolution of solid phase homochirality for a proteinogenic amino acid.

J Am Chem Soc 2008 Nov 28;130(46):15274-5. Epub 2008 Oct 28.

Departamento Cristalografia-Mineralogia, Facultad Geologia, Universidad Complutense, 28040, Madrid, Spain.

The inexorable evolution of solid-phase single chirality is demonstrated for the first time for a proteinogenic amino acid. Enantioenrichment is observed both under attrition-enhanced conditions and without the aid of particle grinding. Differences in the form of the conversion profiles for the process under the two sets of conditions provide suggestions concerning the mechanism of the transformation.
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http://dx.doi.org/10.1021/ja8074506DOI Listing
November 2008

Hominid exploitation of the environment and cave bear populations. The case of Ursus spelaeus Rosenmüller-Heinroth in Amutxate cave (Aralar, Navarra-Spain).

J Hum Evol 2007 Jan 8;52(1):1-15. Epub 2006 Aug 8.

Biomolecular Stratigraphy Laboratory, E.T.S.I. Minas, Universidad Politécnica de Madrid, C/Ríos Rosas 21, E-28003 Madrid, Spain.

Cave bears (Ursus deningeri and U. spelaeus) and hominids (Homo heidelbergensis, H. neanderthalensis, and H. sapiens) were potential competitors for environmental resources (subterranean and open air). Here, we examined the age at death of cave bear (Ursus spelaeus Rosenmüller-Heinroth) specimens from Amutxate cave in order to shed light on the effect of resource sharing between cave bears and hominids. After studying dental wear of the deciduous and permanent dentitions, the ontogenetic development of mandibles, and incremental layers of cement (annuli), we defined five age groups differentiated by marked development and size gaps. Our findings indicate that after hibernating, bears abandoned the den, thereby leaving the subterranean environment (caves) free for temporary hominid occupation-this would explain the subtle traces of hominid presence in many dens. However, a simple calculation based on age at death of subadult and adult cave bear specimens in Amutxate cave, extrapolated to the whole cave area, showed that the area surrounding this cave hosted bears for at least 9,000 years. This length of habitation, quite similar to the time-span derived from amino acid racemization and electron spin resonance, indicates that bear populations in the Amutxate cave constituted a serious constraint for hominid exploitation of the environment.
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http://dx.doi.org/10.1016/j.jhevol.2006.07.013DOI Listing
January 2007
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