Understanding ecosystem resilience requires long data series provided by palaeoecological studies, the best tool for reconstructing vegetation dynamics. Here, we analyzed a continuous and well-dated ...record of pollen, non-pollen palynomorphs, macrocharcoal remains, loss-on-ignition and magnetic susceptibility from one of the most singular peatlands in the Toledo Mountains (central Spain), in order to delineate the anthropogenic and/or climate impact on the peatland and the ecosystem’s response. La Ventilla mire is an isolated site of birch woodland dominated by Betula pubescens subsp. celtiberica (Rothm. & Vasc.) Rivas Mart. This mire, acting as a refugium for this species, is located in Cabañeros National Park and is recognized as ‘Special Area of Conservation’ according to Habitats Directive of the Natura 2000 network. We describe major patterns and trends in the development of this palaeorefugium since the mid-Holocene (∼6145 cal BP) and provide historical context for some natural and/or human-induced dynamics. Around 1500 cal BP, the lotic depositional environment with slow moving backwaters developed into a minerotrophic mire. Until the Middle Ages, macroclimate and autogenic succession appear to have been the main drivers of both local and regional development of vegetation. Between 1500 and 500 cal BP, an abrupt decline in birch cover started, coincident with the Visigothic period. The pronounced peaks in the coprophilous fungi record ca. 1000 and 150 cal BP reflect extensive pastoral activities in the area. This study shows how palaeoecological knowledge helps to explain present patterns in the composition of a valuable protected site, which may be used in prioritizing conservation.
•La Ventilla birch forest confirms the antiquity of birch in the Toledo Mountains.•Toledo Mountains mires have been important refugia for certain species.•Human groups lived and exploited the Toledo Mountains environment since Neolithic.•Palynological studies are useful tools for conservation and landscape management.
N-butylpyridinium chloride (bpyCl) is an ionic liquid (IL) extensively employed as an effective catalyst for many chemical reactions. Therefore, precise monitoring of its concentration can ensure the ...desired high yields in these catalyzed chemical processes. In this work, a fluorescence study has been carried out to determine the concentration of bpyCl in aqueous solution. A light emitting diode (LED), a continuous wave laser diode (CWLD), and a femtosecond pulsed laser (FPL) have been employed as light sources to electronically excite IL samples at a central wavelength of 400nm. The measured fluorescence spectra obtained at different concentrations have been used to design three mathematical models for each one of the light sources. These models rely on artificial neural networks (ANNs) to assess the concentration of IL aqueous solutions in a wide range of concentrations. ANNs have been selected thanks to their ability to discover and adequately interpret nonlinear relationships among datasets. ANNs have been successful due to the existence of a nonlinear dependence between the IL fluorescence signal and its concentration, most likely due to the inner filter effect. The three light sources employed were suitable to fulfill the goal (mean prediction errors were 4.9%, 2.5%, and 1.7% for the LED, CWLD, and FPL models, respectively). These results suggest the existence of a potential source of reliable sensors based on the combination of fluorescence and ANNs. Furthermore, the accurate concentration estimation of many fluorescent compounds in aqueous solution appears achievable and, therefore, applicable to multiple chemical processes.
This paper presents a palynological study of the archeological layers from the Neanderthal site Abrigo 3 del Complejo del Humo, in southern Spain (Málaga), with the aim of reconstructing the ...environmental conditions in the vicinity of this hominin site. The Upper Pleistocene vegetation and its variability are described, revealing a high diversity of thermophilous plant taxa throughout the cold dry phases, together with a long-term persistence of woody taxa, including Mediterranean, mesophytes, xerothermics and conifers. With the pollen records of Maytenus senegalensis as an outstanding finding, this study demonstrates the co-existence of temperate, Mediterranean and Ibero-Maghrebian angiosperms on the southern coastal plains of the Iberian Pleistocene where Neanderthals survived for a long time. It is therefore clear that Neanderthals and early Upper Paleolithic modern humans lived in a litoral refugium, which was a propitious environment for maintaining a high biodiversity, including potentially edible plant species. Besides, this coastal refugium offers broad possibilities for hunting, and interpopulational relationships through coastal platforms.
•A palynological study of the archeological layers from the Neanderthal site of Abrigo 3 del Complejo del Humo.•A high diversity of thermophilous plant taxa throughout the cold dry phases.•The co-existence of temperate, Mediterranean and Ibero-Maghrebian angiosperms in the southern of the Iberian Pleistocene.•Neanderthals and early Upper Paleolithic people lived in a litoral refugium.
A set of 30 modern pollen samples collected in pine communities of the Gúdar Range (southeastern Iberian System) has been investigated to determine the relationships between pollen percentages and ...vegetation composition along a ~1000 m elevation transect. Pollen representation was estimated by comparing the presence of plant taxa from a recent vegetation survey with pollen spectra. Classification and ordination of modern pollen samples indicated the existence of eight vegetation units, which can be assigned to the six studied pine forest communities. Lowland forests are clearly discriminated from high-altitude ones. These analyses also allow separating Pinus nigra and P. pinaster communities according to their tree cover, and even those of P. sylvestris according to the bioclimatic belt they inhabit. We show that it is possible to obtain distinct pollen markers for Mediterranean pine forest communities. These results will also improve the reconstruction of pine forests from fossil pollen diagrams, as far as modern pollen rain studies are carried out in specific regions, an approach which can be extrapolated to other plant formations regardless the involved territory.
•Pollen–vegetation relationships have been established in SE Iberian mountains.•These mountains constitute a key enclave because six Iberian pine species coexist.•Multivariate analyses indicated eight vegetation units assigned to pine communities.•It is possible to obtain pollen markers for Mediterranean pine forests.•Results will improve the reconstruction of pine forests from fossil pollen diagrams.
Summary
A computerised approach to vastly reduce the experimental information required (number of independent variables) to classify similar extra virgin olive oils (EVOOs) is presented. It is based ...on the application of a multilayer perceptron (MLP) and further analysis of the obtained results using differential calculations. To validate this new model, it has been applied for the classification of 147 EVOO samples into four similar families. The oil samples employed came from two types of protected denomination of origin (PDO) oils and two non‐PDO from the same Spanish province (Granada). This approach results in a new method that reduces the necessary size of the databases used, without an appreciable loss of information, by over 82%. The percentage of misclassifications using less data points is similar to the results achieved using the whole database (less than 0.90%).
A nonlinear model based on neural networks has been proposed to estimate the refractive index, density, and viscosity of two ionic liquid (IL) binary mixtures with a common component ...(N-butylpyridinium tetrafluoroborate (bpyBF4) and 4-methyl-N-butylpyridinium bis(trifluoromethylsulfonyl)imide (4mbpyTf2N), and bpyBF4 and N-butylpyridinium bis(trifluoromethylsulfonyl)imide (bpyTf2N)) using their composition (molar fractions) and temperature, which ranged from 273.15 to 353.15 K. The results of the mathematical model were studied through mean prediction errors (MPEs). For the estimation of refractive index, density, and viscosity, the MPEs were 0.02%, 0.11%, and 3.24%, respectively, with a correlation coefficient greater than 0.99 in all cases. In light of these results, the model designed is very accurate and more than capable to assist in the estimation of physicochemical properties of binary mixtures formed by ILs.
Background
The objective of this study was to determine the presence of anti‐Dsg1 and Dsg3 antibodies in healthy subjects of the high Peruvian Amazon (Tuemal, Rodriguez de Mendoza province, ...department of Amazonas) to establish the theoretical presence of environmental factors or triggers in the area.
Materials and methods
Cross‐sectional study. The study population included persons of any age or gender, clinically healthy, who were evaluated by a dermatologist to confirm the absence of blistering diseases. Blood samples were analyzed by indirect immunofluorescence (IIF), immunoprecipitation (IP), anti‐Dsg1 IgM antibody (Ab) enzyme‐linked immunosorbent assay (ELISA), as well as anti‐Dsg1 and anti‐Dsg3 IgG Ab ELISA.
Results
Participants included 21 healthy subjects comprised of 61.9% males and 38.1% females; 47.6% had a positive anti‐Dsg1 Ab ELISA for total IgG (or any subclasses). IIF detected antibodies against intercellular spaces in one subject. Anti‐Dsg1 Ab IP was mildly positive in 33.3% of the subjects. Anti‐Dsg1 IgG subclasses found positive were: IgG1 (19.0%), IgG2 (33.3%), and IgG3 (28.6%); none of the samples were positive for anti‐Dsg1 Ab IgM ELISA, and 23.8% of the subjects were positive for anti‐Dsg3 Ab ELISA. The age distribution was similar for subjects positive for anti‐Dsg1 and anti‐Dsg3 Ab ELISA, with higher frequencies found among the 20–29 and 40–49 year‐old age groups.
Conclusion
A fraction of healthy subjects of the high Peruvian Amazon developed anti‐Dsg1 and anti‐Dsg3 antibodies, demonstrating the possible presence of environmental factors for endemic pemphigus (EP) at a higher altitude than previously described.
This article describes the patterns and processes of vegetation change and fire history in the Late Holocene (c. 2400 calendar year BP) palaeoecological sequence of Lanzahíta, Sierra de Gredos in ...central Spain, and provides the first Iberian pollen sequence undertaken within a monospecific Pinus pinaster woodland. These new data reassess not only the autochthonous nature of this pine species in the region and the Iberian Peninsula, but also the naturalness of well-developed cluster pine forests. Conflicts of palaeoecological evidence with phytosociological models of vegetation dynamics in the study region, and the relationships of P. pinaster with fire occurrence in Mediterranean-type ecosystems, are discussed.
Societal impact statement
There are many understudied fruits of great economic and productive importance for regional agricultural hubs. Guava is an American fruit species with attractive nutritional ...and adaptability characteristics. However, in many countries like Mexico, its cultivation is still limited to small‐to‐medium size plantings and home gardens and depends on poorly controlled germplasm that diminishes productivity and expansion. Our study provides valuable insight to better understand guava diversity and generate high‐yielding, high‐quality, and better adapted materials. Supporting the study and development of understudied crops will provide us with more resources for facing climate change adversities and for diversifying cropping systems.
Summary
Guava (Psidium guajava L.) is a fruit crop species native to tropical and subtropical regions of America with great productive and economic potential due to its extensive environmental adaptability, nutritional value, and medicinal properties. However, the lack of molecular resources for accelerated breeding, limited knowledge about its evolutionary and domestication history, and unfavorable policies have limited its genetic improvement and broader adoption as a commercial fruit crop.
Here, we present the first diversity study in guava employing genome‐wide single nucleotide polymorphisms (SNPs). Forty‐eight accessions collected from Mexico and other continents were examined with more than 6000 high‐quality SNP markers, which represents a marker density increase of ~30x compared with previous studies. Relationships between genetic groupings and geographic origins were not apparent in this diverse guava collection using principal component and structure analyses.
Extensive germplasm exchange among guava‐producing regions and limited varietal control at commercial plantations might have contributed to ambiguities when defining the true origin and identities of existing germplasm materials. However, an analysis of domestication syndrome traits (fruit size and sugar) by wild or improved germplasm revealed several putative genomic regions under selection.
Knowledge about germplasm origins and genetic relatedness, in conjunction with reliable molecular resources and better agronomic practices, is necessary to support breeding efforts and facilitate broader adoption of orphan crops such as guava, which have increasingly important roles in light of climate change adversities and in diversifying diets and food systems.
There are many understudied fruits of great economic and productive importance for regional agricultural hubs. Guava is an American fruit species with attractive nutritional and adaptability characteristics. However, in many countries like Mexico, its cultivation is still limited to small‐to‐medium size plantings and home gardens and depends on poorly controlled germplasm that diminishes productivity and expansion. Our study provides valuable insight to better understand guava diversity and generate high‐yielding, high‐quality, and better adapted materials. Supporting the study and development of understudied crops will provide us with more resources for facing climate change adversities and for diversifying cropping systems.
