Publications by authors named "Néstor Fernández"

30 Publications

  • Page 1 of 1

Priority list of biodiversity metrics to observe from space.

Nat Ecol Evol 2021 May 13. Epub 2021 May 13.

Institute of Geography and Geology, University of Wuerzburg, Würzburg, Germany.

Monitoring global biodiversity from space through remotely sensing geospatial patterns has high potential to add to our knowledge acquired by field observation. Although a framework of essential biodiversity variables (EBVs) is emerging for monitoring biodiversity, its poor alignment with remote sensing products hinders interpolation between field observations. This study compiles a comprehensive, prioritized list of remote sensing biodiversity products that can further improve the monitoring of geospatial biodiversity patterns, enhancing the EBV framework and its applicability. The ecosystem structure and ecosystem function EBV classes, which capture the biological effects of disturbance as well as habitat structure, are shown by an expert review process to be the most relevant, feasible, accurate and mature for direct monitoring of biodiversity from satellites. Biodiversity products that require satellite remote sensing of a finer resolution that is still under development are given lower priority (for example, for the EBV class species traits). Some EBVs are not directly measurable by remote sensing from space, specifically the EBV class genetic composition. Linking remote sensing products to EBVs will accelerate product generation, improving reporting on the state of biodiversity from local to global scales.
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http://dx.doi.org/10.1038/s41559-021-01451-xDOI Listing
May 2021

Revision of the family Carabodidae (Acari: Oribatida) XVII. Redescription of Diplobodes africanus Mahunka, 1987 from Kenia. Description of Diplobodes thailande sp. nov. from Thailand and Rwandabodes kayoveae gen. nov., sp. nov. from Rwanda.

Zootaxa 2019 Jun 20;4619(3):zootaxa.4619.3.1. Epub 2019 Jun 20.

National Council of Scientific and Technological Research, Argentina (CONICET). Subtropical Biological Institute (IBS). Evolutive Genetic Laboratory FCEQyN, Misiones National University. Felix de Azara 1552, 6º, (3300) Posadas Misiones Argentina. Research Unit for Environmental Sciences and Management, North-West University, Potchefstroom Campus, 2520, South Africa..

Diplobodes africanus Mahunka, 1987, is redescribed by using Scanning Electron Microscopy (SEM) in order to complement optical microscopy. Diplobodes thailande sp. nov. from Thailand is described. For both species we include inclined views, to permit detailed analysis of ventral regions and to aid understanding of the complex relationships between elevated and depressed zones. Diplobodes thailande sp. nov. presents previously undescribed structures on legs III, which are involved in the leg folding process. Rwandabodes kayoveae gen. nov., sp. nov. presents a series of particular characteristics, such as: elevated interlamellar process on prodorsum, composed of a triangular structure, externally delimited by a low lamellar furrow; in setae inserted on elevated interlamellar process; large free lamellar tip; notogaster lacking ridges; anterior genital furrow extends into an oblique lateral depression; depressed area anterior to anal zone; both zones clearly delimited. These characteristics permit easy differentiation from related genera.
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http://dx.doi.org/10.11646/zootaxa.4619.3.1DOI Listing
June 2019

Rewilding complex ecosystems.

Science 2019 04;364(6438)

Department of Biology, Anglia Ruskin University, Cambridge, UK.

The practice of rewilding has been both promoted and criticized in recent years. Benefits include flexibility to react to environmental change and the promotion of opportunities for society to reconnect with nature. Criticisms include the lack of a clear conceptualization of rewilding, insufficient knowledge about possible outcomes, and the perception that rewilding excludes people from landscapes. Here, we present a framework for rewilding that addresses these concerns. We suggest that rewilding efforts should target trophic complexity, natural disturbances, and dispersal as interacting processes that can improve ecosystem resilience and maintain biodiversity. We propose a structured approach to rewilding projects that includes assessment of the contributions of nature to people and the social-ecological constraints on restoration.
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http://dx.doi.org/10.1126/science.aav5570DOI Listing
April 2019

Revision of the family Carabodidae (Acari: Oribatida) XVI. Synkrotima tsalakpmenoi sp. nov. from Zimbabwe and Kenya, and Congocepheus thailandae sp. nov. from Thailand, including a complementary study of Cavaecarabodes hauseri (Mahunka 1989).

Zootaxa 2018 Oct 25;4504(3):371-389. Epub 2018 Oct 25.

National Council of Scientific and Technological Research, Argentina (CONICET ). Evolutive Genetic Laboratory FCEQyN , Misiones National University. Felix de Azara 1585, 6º (3300) Posadas Misiones Argentina. Research Unit for Environmental Sciences and Development, North-West University, Potchefstroom Campus, 2520, South Africa..

Synkrotima tsalakpmenoi sp. nov. is described from material collected in Zimbabwe and Kenya. This species presents the following characteristics: notogastral integument formed by longitudinally aligned cuticular cords; thick, lanceolate notogastral setae; and genital neotrichy. Synkrotima tsalakpmenoi sp. nov. is compared to S. zimbabwae. Congocepheus thailandae sp. nov. is the first species of this genus described from Thailand, with the following present: large finger-like notogastral projection; notogastral setae c1, c2, da, dm, dp, la, lm, lp, h1, h2 situated on promontories; setae c1, c2 located adjacent and parallel.        A complementary study of Cavaecarabodes hauseri, making use of Scanning Electron Microscopy (SEM), allows for clarification of particularities regarding complex setae as well as some aspects of the integument, and provides a more detailed diagnosis.
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http://dx.doi.org/10.11646/zootaxa.4504.3.4DOI Listing
October 2018

Measuring rewilding progress.

Philos Trans R Soc Lond B Biol Sci 2018 10 22;373(1761). Epub 2018 Oct 22.

German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig 04103, Germany.

Rewilding is emerging as a promising restoration strategy to enhance the conservation status of biodiversity and promote self-regulating ecosystems while re-engaging people with nature. Overcoming the challenges in monitoring and reporting rewilding projects would improve its practical implementation and maximize its conservation and restoration outcomes. Here, we present a novel approach for measuring and monitoring progress in rewilding that focuses on the ecological attributes of rewilding. We devised a bi-dimensional framework for assessing the recovery of processes and their natural dynamics through (i) decreasing human forcing on ecological processes and (ii) increasing ecological integrity of ecosystems. The rewilding assessment framework incorporates the reduction of material inputs and outputs associated with human management, as well as the restoration of natural stochasticity and disturbance regimes, landscape connectivity and trophic complexity. Furthermore, we provide a list of potential activities for increasing the ecological integrity after reviewing the evidence for the effectiveness of common restoration actions. For illustration purposes, we apply the framework to three flagship restoration projects in the Netherlands, Switzerland and Argentina. This approach has the potential to broaden the scope of rewilding projects, facilitate sound decision-making and connect the science and practice of rewilding.This article is part of the theme issue 'Trophic rewilding: consequences for ecosystems under global change'.
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http://dx.doi.org/10.1098/rstb.2017.0433DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6231071PMC
October 2018

Two new species of the family Nippobodidae (Acari, Oribatida), including a description of the leg-folding process.

Zookeys 2018 14(781):109-139. Epub 2018 Aug 14.

National Institute Agricultural Technology (INTA), Experimental Rural Agency, Aimogastam, Argentina National Institute Agricultural Technology, Experimental Rural Agency Aimogasta Argentina.

and are described by means of optical and Scanning Electron Microscopy (SEM) and compared to other congeners. The leg-folding process is described and illustrated. is characterised by interlocking, double hook-shaped, posterior prodorsal condyle and anterior zone humeral apophysis; posterior prodorsal depression present. Tutorium a large lamina defining a pocket-shaped structure; bothridial opening ovoid, situated at the bottom of a U-shaped structure; deep, rounded-ovoid anterior notogastral depression present; ten pairs of notogastral setae; setae looped, dentate, sharply tipped. Marginal setae , on large promontories, followed by deep V-shaped incision; notogaster completely surrounded by circumgastric depression; lateral genital zone with locking structure constituted by longitudinal cuticular elevation, with promontories and a parallel furrow involved in the leg-folding process; genital plate smaller than anal plate. is characterised by: the presence of posterior prodorsal depression and anterior notogastral depression; bridge-shaped anterior prodorsal condyles; heart-shaped frontal prodorsal orifice; ten pairs of notogastral setae; posterior prodorsal condyle and humeral condyle interlocked, forming double hook-like structure; circumgastric furrow surrounding entire notogaster; setae situated on shallow medial furrow; notogastral setae , , , medially aligned; marginally situated. Legs I-IV, tutorium, pedotectum I, and pedotectum II involved in leg folding which is inferred to be a protection mechanism.
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http://dx.doi.org/10.3897/zookeys.781.27389DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6160759PMC
August 2018

The family Lohmanniidae (Acari, Oribatida) II: two new Oribatid mites, sp. n. from Costa Rica and sp. n. from Kenya.

Zookeys 2018 14(743):43-66. Epub 2018 Mar 14.

Laboratory for Electron Microscopy, North-West University, Potchefstroom Campus, 2520, South Africa.

Two very particular new species of the family Lohmanniidae were studied and described using optical and Scanning Electron Microscopy (SEM). displays complex cuticular microsculpture with cross-shaped grooves and pusticulate porose areas; ten transversal bands, with reticulate-foveate microsculpture; , , , not crossing medial notogastral plane, amongst other characters. with: prodorsum - rostrum weakly bilobate with small central structure and CSO present. Six transversal depressions present, transversal bands absent; but six transversal depressions present, none of the depressions crossing medial notogastral plane.
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http://dx.doi.org/10.3897/zookeys.743.22815DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5904501PMC
March 2018

Depletion of the membrane-fusion regulator Munc18c attenuates caerulein hyperstimulation-induced pancreatitis.

J Biol Chem 2018 02 28;293(7):2510-2522. Epub 2017 Dec 28.

From the Departments of Medicine and

Epithelial pancreatic acinar cells perform crucial functions in food digestion, and acinar cell homeostasis required for secretion of digestive enzymes relies on SNARE-mediated exocytosis. The ubiquitously expressed Sec1/Munc18 protein mammalian uncoordinated-18c (Munc18c) regulates membrane fusion by activating syntaxin-4 (STX-4) to bind cognate SNARE proteins to form a SNARE complex that mediates exocytosis in many cell types. However, in the acinar cell, Munc18c's functions in exocytosis and homeostasis remain inconclusive. Here, we found that pancreatic acini from Munc18c-depleted mice (Munc18c) and human pancreas (lenti-Munc18c-shRNA-treated) exhibit normal apical exocytosis of zymogen granules (ZGs) in response to physiologic stimulation with the intestinal hormone cholecystokinin (CCK-8). However, when stimulated with supraphysiologic CCK-8 levels to mimic pancreatitis, Munc18c-depleted (Munc18c) mouse acini exhibited a reduction in pathological basolateral exocytosis of ZGs resulting from a decrease in fusogenic STX-4 SNARE complexes. This reduced basolateral exocytosis in part explained the less severe pancreatitis observed in Munc18c mice after hyperstimulation with the CCK-8 analog caerulein. Likely as a result of this secretory blockade, Munc18c-depleted acini unexpectedly activated a component of the endoplasmic reticulum (ER) stress response that contributed to autophagy induction, resulting in downstream accumulation of autophagic vacuoles and autolysosomes. We conclude that Munc18c's role in mediating ectopic basolateral membrane fusion of ZGs contributes to the initiation of CCK-induced pancreatic injury, and that blockade of this secretory process could increase autophagy induction.
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http://dx.doi.org/10.1074/jbc.RA117.000792DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5818203PMC
February 2018

Revision of the family Carabodidae (Acari, Oribatida) XII. sp. n. and sp. n.

Zookeys 2017 4(706):31-50. Epub 2017 Oct 4.

Laboratory for Electron Microscopy, North-West University, Potchefstroom Campus, 2520 South Africa.

, collected in Cameroon, is the first species of this genus reported from the Afrotropical region. Diagnostic characters include lamellae terminating in a bridge and not in lamellar tips; cup-shaped bothridia, bothridial ring present; rostral setae cochleariform, smooth; lamellar setae slightly lanceolate, barbate; fifteen pairs of notogastral setae; lanceolate, rounded end, with longitudinal shallow grooves; other notogastral setae curved lanceolate-cochleariform. is the third species of the genus to be described, and the first collected outside the African region. Prodorsum presents a Y-shaped structure; elevated interlamellar process, superior flat zone; lamellae lacking lamellar tips; fourteen pairs of notogastral setae; four notogastral furrows, and an unpaired elevated central area devoid of setae. Both species are described and illustrated based on adult specimens, studied by means of optical and SEM microscopy.
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http://dx.doi.org/10.3897/zookeys.706.14807DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5674084PMC
October 2017

Two new Oribatid mites from Costa Rica, sp. n. and sp. n. (Acari, Oribatida, Lohmanniidae).

Zookeys 2017 14(680):33-56. Epub 2017 Jun 14.

Laboratory for Electron Microscopy, North-West University, Potchefstroom Campus, 2520, South Africa.

In this paper we describe two new species belonging to the family Lohmanniidae: and from Costa Rica.
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http://dx.doi.org/10.3897/zookeys.680.13213DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5523379PMC
June 2017

Building essential biodiversity variables (EBVs) of species distribution and abundance at a global scale.

Biol Rev Camb Philos Soc 2018 02 2;93(1):600-625. Epub 2017 Aug 2.

Global Biodiversity Information Facility Secretariat, Universitetsparken 15, 2100, København Ø, Denmark.

Much biodiversity data is collected worldwide, but it remains challenging to assemble the scattered knowledge for assessing biodiversity status and trends. The concept of Essential Biodiversity Variables (EBVs) was introduced to structure biodiversity monitoring globally, and to harmonize and standardize biodiversity data from disparate sources to capture a minimum set of critical variables required to study, report and manage biodiversity change. Here, we assess the challenges of a 'Big Data' approach to building global EBV data products across taxa and spatiotemporal scales, focusing on species distribution and abundance. The majority of currently available data on species distributions derives from incidentally reported observations or from surveys where presence-only or presence-absence data are sampled repeatedly with standardized protocols. Most abundance data come from opportunistic population counts or from population time series using standardized protocols (e.g. repeated surveys of the same population from single or multiple sites). Enormous complexity exists in integrating these heterogeneous, multi-source data sets across space, time, taxa and different sampling methods. Integration of such data into global EBV data products requires correcting biases introduced by imperfect detection and varying sampling effort, dealing with different spatial resolution and extents, harmonizing measurement units from different data sources or sampling methods, applying statistical tools and models for spatial inter- or extrapolation, and quantifying sources of uncertainty and errors in data and models. To support the development of EBVs by the Group on Earth Observations Biodiversity Observation Network (GEO BON), we identify 11 key workflow steps that will operationalize the process of building EBV data products within and across research infrastructures worldwide. These workflow steps take multiple sequential activities into account, including identification and aggregation of various raw data sources, data quality control, taxonomic name matching and statistical modelling of integrated data. We illustrate these steps with concrete examples from existing citizen science and professional monitoring projects, including eBird, the Tropical Ecology Assessment and Monitoring network, the Living Planet Index and the Baltic Sea zooplankton monitoring. The identified workflow steps are applicable to both terrestrial and aquatic systems and a broad range of spatial, temporal and taxonomic scales. They depend on clear, findable and accessible metadata, and we provide an overview of current data and metadata standards. Several challenges remain to be solved for building global EBV data products: (i) developing tools and models for combining heterogeneous, multi-source data sets and filling data gaps in geographic, temporal and taxonomic coverage, (ii) integrating emerging methods and technologies for data collection such as citizen science, sensor networks, DNA-based techniques and satellite remote sensing, (iii) solving major technical issues related to data product structure, data storage, execution of workflows and the production process/cycle as well as approaching technical interoperability among research infrastructures, (iv) allowing semantic interoperability by developing and adopting standards and tools for capturing consistent data and metadata, and (v) ensuring legal interoperability by endorsing open data or data that are free from restrictions on use, modification and sharing. Addressing these challenges is critical for biodiversity research and for assessing progress towards conservation policy targets and sustainable development goals.
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http://dx.doi.org/10.1111/brv.12359DOI Listing
February 2018

Predicting herbivore faecal nitrogen using a multispecies near-infrared reflectance spectroscopy calibration.

PLoS One 2017 28;12(4):e0176635. Epub 2017 Apr 28.

Ruminant Research Group, Departament de Ciència Animal i dels Aliments, Universitat Autònoma de Barcelona (UAB), Bellaterra, Barcelona, Spain.

Optimal management of free-ranging herbivores requires the accurate assessment of an animal's nutritional status. For this purpose 'near-infrared reflectance spectroscopy' (NIRS) is very useful, especially when nutritional assessment is done through faecal indicators such as faecal nitrogen (FN). In order to perform an NIRS calibration, the default protocol recommends starting by generating an initial equation based on at least 50-75 samples from the given species. Although this protocol optimises prediction accuracy, it limits the use of NIRS with rare or endangered species where sample sizes are often small. To overcome this limitation we tested a single NIRS equation (i.e., multispecies calibration) to predict FN in herbivores. Firstly, we used five herbivore species with highly contrasting digestive physiologies to build monospecies and multispecies calibrations, namely horse, sheep, Pyrenean chamois, red deer and European rabbit. Secondly, the equation accuracy was evaluated by two procedures using: (1) an external validation with samples from the same species, which were not used in the calibration process; and (2) samples from different ungulate species, specifically Alpine ibex, domestic goat, European mouflon, roe deer and cattle. The multispecies equation was highly accurate in terms of the coefficient of determination for calibration R2 = 0.98, standard error of validation SECV = 0.10, standard error of external validation SEP = 0.12, ratio of performance to deviation RPD = 5.3, and range error of prediction RER = 28.4. The accuracy of the multispecies equation to predict other herbivore species was also satisfactory (R2 > 0.86, SEP < 0.27, RPD > 2.6, and RER > 8.1). Lastly, the agreement between multi- and monospecies calibrations was also confirmed by the Bland-Altman method. In conclusion, our single multispecies equation can be used as a reliable, cost-effective, easy and powerful analytical method to assess FN in a wide range of herbivore species.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0176635PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5409079PMC
September 2017

Two new oribatid mites from the Republic of Rwanda. Plasmobates zarae sp. n. (Acari, Plasmobatidae) and Basilobelba spasmenosi sp. n. (Acari, Basilobelbidae).

Zookeys 2016 14(598):1-25. Epub 2016 Jun 14.

Research Unit for Environmental Sciences and Management, North-West University, Potchefstroom Campus, 2520 (South Africa).

Two new species of oribatid mites, Plasmobates zarae sp. n. and Basilobelba spasmenosi sp. n. are described from the Republic of Rwanda. They can easily be differentiated from other species by a number of characters. Plasmobates zarae sp. n. is differentiated the following characters. four types of particular cerotegumental layers. Integument slightly foveate to smooth on prodorsum; foveate on notogaster; ventral region rugose to smooth.Large rostral setae inserted on protuberance, whip-shaped, with longitudinal pucker; interlamellar setae rod-shaped with triangular scales; interlamellar setae small. Medial band on prodorsum extending to anterior of central part, but not reaching rostrum. Bothridium horn-shaped; opening basally incised with rectilinear wall, internal bothridial rings dentate. Sensillus whip-like, with minute triangular scales. Variably distributed circumgastric macropores. Opisthosomal gland apophysis flat, triangular in lateral view and cylindrical in posterolateral view. Six pairs of notogastral setae, all situated posterior to opisthosomal gland level. Aggenital setae not detected; three pairs of adanal setae; two pairs of anal setae present. Nymphal scalps simple without anterior tuft or filaments, with dentate peripheral ridge. Larval scalp shaped like Chinese hat. Basilobelba spasmenosi sp. n. is characterized by the combination of the following characters: Cerotegument: thick basal layer with amorphous coat and cavities of different sizes, as well as structures resembling small cauliflowers. Setation: simple: notogastral, epimeral, genital, anal; simple long, basally barbate: le, ro setae; simple, whip-shaped: ex setae; medium length, sharpened tip with thorns on surface: in setae, leg setae; Flabellate: setae situated in ventral neotrichous zone. Thorn-like barbs and more or less parallel longitudinal grooves present on body surface of le, ro, in and leg setae. Prodorsum: rostrum finger-shaped, relative sizes of setae: le > ro > in > ex. Prodorsal cuticular surface smooth with shallow transversal furrow and two oblique furrows determining two triangular structures. Large humpbacked CSO situated anterior to and in medial line with in setal insertion, dorsal bothridial opening. Notogaster swollen, hemispheric; nine pairs of minute setae, only h1 , h2 , h3 easily identifiable, cuticular wart and dimple clearly visible. Humeral apophysis with longitudinal furrow dorsally. Elongate chelicera with cha, chb setae, behind them a series of scales directed dorsoventrally. Epimeral setation 3-1-3-3, adanal-aggenital neotrichy with between 8-10 setae. Nymphal scalps with very particular bean-shaped structure on either side of the decoupage zone, surrounding horn-like structure. Scalps with cuticular polyhedral reticulate to ovoid structure, often forming a cavity, either completely perforated or with a thin cuticular layer resembling an interior membrane.
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http://dx.doi.org/10.3897/zookeys.598.8972DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4926670PMC
July 2016

Fine-Scale Habitat Segregation between Two Ecologically Similar Top Predators.

PLoS One 2016 17;11(5):e0155626. Epub 2016 May 17.

Department of Conservation Biology, Estación Biológica de Doñana, CSIC, Avda. Américo Vespucio s/n, 41092, Sevilla, Spain.

Similar, coexisting species often segregate along the spatial ecological axis. Here, we examine if two top predators (jaguars and pumas) present different fine-scale habitat use in areas of coexistence, and discuss if the observed pattern can be explained by the risk of interference competition between them. Interference competition theory predicts that pumas should avoid habitats or areas used by jaguars (the dominant species), and as a consequence should present more variability of niche parameters across study areas. We used non-invasive genetic sampling of faeces in 12 different areas and sensor satellite fine-scale habitat indices to answer these questions. Meta-analysis confirmed differences in fine-scale habitat use between jaguars and pumas. Furthermore, average marginality of the realized niches of pumas was more variable than those of jaguars, and tolerance (a measure of niche breadth) was on average 2.2 times higher in pumas than in jaguars, as expected under the interference competition risk hypothesis. The use of sensor satellite fine-scale habitat indices allowed the detection of subtle differences in the environmental characteristics of the habitats used by these two similar top predators, which, as a rule, until now were recorded using the same general habitat types. The detection of fine spatial segregation between these two top predators was scale-dependent.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0155626PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4871328PMC
July 2017

Variability in primary productivity determines metapopulation dynamics.

Proc Biol Sci 2016 04;283(1828)

Department of Conservation Biology, Estación Biológica de Doñana, Spanish Council for Scientific Research EBD-CSIC, Seville 41092, Spain.

Temporal variability in primary productivity can change habitat quality for consumer species by affecting the energy levels available as food resources. However, it remains unclear how habitat-quality fluctuations may determine the dynamics of spatially structured populations, where the effects of habitat size, quality and isolation have been customarily assessed assuming static habitats. We present the first empirical evaluation on the effects of stochastic fluctuations in primary productivity--a major outcome of ecosystem functions--on the metapopulation dynamics of a primary consumer. A unique 13-year dataset from an herbivore rodent was used to test the hypothesis that inter-annual variations in primary productivity determine spatiotemporal habitat occupancy patterns and colonization and extinction processes. Inter-annual variability in productivity and in the growing season phenology significantly influenced habitat colonization patterns and occupancy dynamics. These effects lead to changes in connectivity to other potentially occupied habitat patches, which then feed back into occupancy dynamics. According to the results, the dynamics of primary productivity accounted for more than 50% of the variation in occupancy probability, depending on patch size and landscape configuration. Evidence connecting primary productivity dynamics and spatiotemporal population processes has broad implications for metapopulation persistence in fluctuating and changing environments.
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http://dx.doi.org/10.1098/rspb.2015.2998DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4843648PMC
April 2016

Revision of the family Carabodidae (Acari, Oribatida) V. Fourth part. Two new species of the genus Congocepheus from the Republic of Rwanda: Congocepheus rwandensis sp. n., and Congocepheus kayoveae sp. n.

Zookeys 2016 21(556):19-41. Epub 2016 Jan 21.

Fellowship, National Institute Agricultural Technology (INTA). Experimental Rural Agency, Aimogasta.

Two new species from Rwanda are described utilizing optical and scanning electron microscope observations: Congocepheus rwandensis sp. n. and Congocepheus kayoveae sp. n. are compared to Congocepheus taurus Balogh 1961.
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http://dx.doi.org/10.3897/zookeys.556.7011DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4740870PMC
February 2016

Fecal nitrogen concentration as a nutritional quality indicator for European rabbit ecological studies.

PLoS One 2015 20;10(4):e0125190. Epub 2015 Apr 20.

Department of Conservation Biology, Estación Biológica, Spanish Council for Scientific Research CSIC, Seville, Spain.

Measuring the quality of the nutritional resources available to wild herbivores is critical to understanding trophic regulation processes. However, the direct assessment of dietary nutritional characteristics is usually difficult, which hampers monitoring nutritional constraints in natural populations. The feeding ecology of ruminant herbivores has been often assessed by analyzing fecal nitrogen (FN) concentrations, although this method has been less evaluated in other taxa. This study analyzed the suitability of FN as an indicator of ingesta quality in the European rabbit (Oryctolagus cuniculus), which is a keystone lagomorph species in Mediterranean ecosystems and of great conservation interest. Firstly, domestic O. cuniculus were used to evaluate under experimental conditions the accuracy of total FN and the metabolic FN as diet quality indicators of forages with characteristics similar to those available under natural conditions. Secondly, the accuracy of Near-Infrared Spectroscopy (NIRS) to calculate FN was tested using partial least squares regression. Thirdly, a pilot field study was conducted to monitor FN dynamics from wild O. cuniculus in three different habitats during wet and drought periods. A strong association was found between diet type and total FN and metabolic FN (Pseudo-R(2) ≥ 0.89). It was also found that NIRS calibrations were accurate for depicting nitrogen concentrations (R(2) > 0.98 between NIRS and chemical results). Finally, the seasonal FN dynamics measured in the field were consistent with current knowledge on vegetation dynamics and forage limitations in the three habitats. The results support the use of NIRS methods and FN indices as a reliable and affordable approach to monitoring the nutritional quality of rabbit habitats. Potential applications include the assessment of the mechanistic relationships between resource limitations and population abundance, e.g., in relation to natural drought cycles and to habitat interventions aimed at reinforcing rabbit populations.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0125190PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4404320PMC
April 2016

The family Carabodidae (Acari, Oribatida) VIII. The genus Machadocepheus (first part) Machadocepheusleoneae sp. n. and Machadocepheusrachii sp. n. from Gabon.

Zookeys 2014 21(456):1-28. Epub 2014 Nov 21.

Fellowship, National Institute Agricultural Technology (INTA). Experimental Rural Agency, Aimogasta. 5310. La Rioja. Argentina.

The genus Machadocepheus, being one of the more complex genera of the Carabodidae family, is briefly outlined to demonstrate this complexity. Descriptions of two new species from Gabon, Machadocepheusleoneae sp. n. and Machadocepheusrachii sp. n. are given.
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http://dx.doi.org/10.3897/zookeys.456.8570DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4283057PMC
January 2015

Revision of the family Carabodidae (Acari, Oribatida) VII. Redefinition of the genus Malgasodes; redescription of M. curvisetus Mahunka, 2000; and complementary description of M. hungarorum Mahunka, 2010. Phylogenetic relationships between Malgasodes, Bovicarabodes, Afticarabodes, Congocepheus and Cavaecarabodes are discussed.

Zookeys 2014 15(435):25-48. Epub 2014 Aug 15.

National Council of Scientific and Technological Research, Argentina (CONICET). Subtropical Biological Institut (IBS). Evolutive Genetic Laboratory FCEQyN, Misiones National University. Felix de Azara 1552, 6°, (3300) Posadas Misiones Argentina.

The genus Malgasodes is redefined; the type species M. curvisetus Mahunka, 2000, is redescribed by means of studies using optic and Scanning Electron Microsopy (SEM), and a complementary description of M. hungarorum Mahunka, 2000 is included. Comparison of genera Malgasodes Mahunka, 2000, Bovicarabodes Fernandez, Theron, Rollard, 2013a, Cavaecarabodes Fernandez, Theron, Rollard, Rodriguez Castillo, 2014, Afticarabodes Fernandez, Theron, Rollard, 2013b, and Congocepheus Balogh, 1958 is made. Problems concerning chaetotaxy, regressive evolution and neotrichy are explained and phylogenetic relationships between Malgasodes, Bovicarabodes, Afticarabodes, Congocepheus and Cavaecarabodes are discussed.
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http://dx.doi.org/10.3897/zookeys.435.8071DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4141185PMC
August 2014

ATM regulates 3-methylpurine-DNA glycosylase and promotes therapeutic resistance to alkylating agents.

Cancer Discov 2014 Oct 6;4(10):1198-213. Epub 2014 Aug 6.

Arthur and Sonia Labatt Brain Tumour Research Centre, The Hospital for Sick Children, Toronto, Canada. Division of Pathology, The Hospital for Sick Children, University of Toronto, Toronto, Canada.

Unlabelled: Alkylating agents are a first-line therapy for the treatment of several aggressive cancers, including pediatric glioblastoma, a lethal tumor in children. Unfortunately, many tumors are resistant to this therapy. We sought to identify ways of sensitizing tumor cells to alkylating agents while leaving normal cells unharmed, increasing therapeutic response while minimizing toxicity. Using an siRNA screen targeting over 240 DNA damage response genes, we identified novel sensitizers to alkylating agents. In particular, the base excision repair (BER) pathway, including 3-methylpurine-DNA glycosylase (MPG), as well as ataxia telangiectasia mutated (ATM), were identified in our screen. Interestingly, we identified MPG as a direct novel substrate of ATM. ATM-mediated phosphorylation of MPG was required for enhanced MPG function. Importantly, combined inhibition or loss of MPG and ATM resulted in increased alkylating agent-induced cytotoxicity in vitro and prolonged survival in vivo. The discovery of the ATM-MPG axis will lead to improved treatment of alkylating agent-resistant tumors.

Significance: Inhibition of ATM and MPG-mediated BER cooperate to sensitize tumor cells to alkylating agents, impairing tumor growth in vitro and in vivo with no toxicity to normal cells, providing an ideal therapeutic window.
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http://dx.doi.org/10.1158/2159-8290.CD-14-0157DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4184920PMC
October 2014

Nannodromus reveilleti (Acari, Anystida, Saxidromidae) a new genus and species from South Africa.

Zookeys 2014 6(378):17-39. Epub 2014 Feb 6.

Laboratory for Electron Microscopy, North-West University, Potchefstroom Campus, Private Bag X6001, Potchefstroom, 2520 South Africa.

The description of a new genus Nannodromus and a new species Nannodromus reveilleti (Acari: Anystides: Saxidromidae) from South Africa, based on adult males and females.
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http://dx.doi.org/10.3897/zookeys.378.6753DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3935426PMC
February 2014

Agistemus aimogastaensis sp. n. (Acari, Actinedida, Stigmaeidae), a recently discovered predator of eriophyid mites Aceria oleae and Oxycenus maxwelli, in olive orchards in Argentina.

Zookeys 2013 26(312):65-78. Epub 2013 Jun 26.

Fellowship, National Institute Agricultural Technology (INTA). Experimental Rural Agency, Aimogasta. 5310. La Rioja. Argentina.

A new species, Agistemus aimogastaensis, is described with the aid of optical and Scanning Electron Microscopy. This mite is an important predator of two eriophyid mites (Aceria oleae and Oxycenus maxwelli) in olive orchards (Olea europaea, variety Arauco) in La Rioja Province. The problems related to eriophyids in olive orchards in Argentina are highlighted and photos of the damage on leaves and fruit are included.
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http://dx.doi.org/10.3897/zookeys.312.5520DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3698566PMC
July 2013

Individual and spatio-temporal variations in the home range behaviour of a long-lived, territorial species.

Oecologia 2013 Jun 20;172(2):371-85. Epub 2012 Oct 20.

Department of Conservation Biology, Estación Biológica de Doñana, C.S.I.C., c/Americo Vespucio s/n, 41092, Seville, Spain.

Despite the fact that investigations of home range behaviour have exponentially evolved on theoretical, analytical and technological grounds, the factors that shape animal home range behaviour still represent an unsolved question and a challenging field of research. However, home range studies have recently begun to be approached under a new integrated conceptual framework, considering home range behaviour as the result of the simultaneous influences of temporal, spatial and individual-level processes, with potential consequences at the population level. Following an integrated approach, we studied the influence of both external and internal factors on variations in the home range behaviour of 34 radiotagged eagle owl (Bubo bubo) breeders. Home range behaviour was characterised through complementary analysis of space use, movement patterns and rhythms of activity at multiple spatio-temporal scales. The effects of the different phases of the biological cycle became considerably evident at the level of movement patterns, with males travelling longer distances than females during incubation and nestling periods. Both external (i.e. habitat structure and composition) and internal (i.e. sex and health state) factors explained a substantial amount of the variation in home range behaviour. At the broader temporal scale, home range and core area size were negatively correlated with landscape heterogeneity. Males showed (1) smaller home range and core area sizes, (2) more complex home range internal structure and (3) higher rates of movement. The better the physiological condition of the individuals, the simpler the internal home range structure. Finally, inter- and intra-individual effects contributed to shaping space use and movement patterns during the biological cycle. Because of the plurality of behavioural and ecological processes simultaneously involved in home range behaviour, we claim that an integrative approach is required for adequate investigation of its temporal and spatial variation.
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http://dx.doi.org/10.1007/s00442-012-2493-7DOI Listing
June 2013

Mg/Ca partitioning between aqueous solution and aragonite mineral: a molecular dynamics study.

Chemistry 2012 Aug 28;18(32):9828-33. Epub 2012 Jun 28.

Department of Chemistry, University College London, 20 Gordon St. London WC1H 0AJ, United Kingdom.

We have calculated the concentrations of Mg in the bulk and surfaces of aragonite CaCO(3) in equilibrium with aqueous solution, based on molecular dynamics simulations and grand-canonical statistical mechanics. Mg is incorporated in the surfaces, in particular in the (001) terraces, rather than in the bulk of aragonite particles. However, the total Mg content in the bulk and surface of aragonite particles was found to be too small to account for the measured Mg/Ca ratios in corals. We therefore argue that most Mg in corals is either highly metastable in the aragonite lattice, or is located outside the aragonite phase of the coral skeleton, and we discuss the implications of this finding for Mg/Ca paleothermometry.
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http://dx.doi.org/10.1002/chem.201200966DOI Listing
August 2012

Effects of ethanol metabolites on exocytosis of pancreatic acinar cells in rats.

Gastroenterology 2012 Sep 15;143(3):832-843.e7. Epub 2012 Jun 15.

Department of Medicine, University of Toronto, Toronto, Ontario, Canada; Department of Physiology, University of Toronto, Toronto, Ontario, Canada. Electronic address:

Background & Aims: During development of alcoholic pancreatitis, oxidative (acetaldehyde) and nonoxidative metabolites (ethyl palmitate, ethyl oleate), rather than ethanol itself, mediate toxic injury. Exposure of pancreatic acini to ethanol blocks cholecystokinin (CCK)-8-stimulated apical exocytosis and redirects exocytosis to the basolateral plasma membrane, causing interstitial pancreatitis. We examined how each ethanol metabolite contributes to these changes in exocytosis.

Methods: Rat pancreatic acini were incubated with concentrations of ethanol associated with alcoholic pancreatitis (20-50 mmol/L) or ethanol metabolites (1-3 mmol/L) and then stimulated with CCK-8. We performed single zymogen granule (ZG) exocytosis assays, Ca(2+) imaging studies, ultrastructural analyses (with electron microscopy), and confocal microscopy to assess the actin cytoskeleton and track the movement of vesicle-associated membrane protein (VAMP)-8-containing ZGs. Coimmunoprecipitation assays were used to identify complexes that contain the distinct combinations of Munc18 and the soluble N-ethylmaleimide sensitive factor attachment protein receptor proteins, which mediate apical (ZG-apical plasma membrane) and basolateral exocytosis and fusion between ZGs (ZG-ZG).

Results: The ethanol metabolites acetaldehyde, ethyl palmitate, and ethyl oleate reduced CCK-8-stimulated apical exocytosis and formation of apical exocytotic complexes (between Munc18b and Syntaxin-2, synaptosomal-associated protein of 23 kilodaltons [SNAP23], and VAMP2) in rat pancreatic acini. Acetaldehyde and ethyl oleate redirected CCK-8-stimulated exocytosis to the basal and lateral plasma membranes and translocation of VAMP8-containing ZGs toward the basolateral plasma membrane. This process was mediated primarily via formation of basolateral exocytotic complexes (between Munc18c and Syntaxin-4, SNAP23, and VAMP8). Exposure of the acini to acetaldehyde and ethyl oleate followed by CCK-8 stimulation mildly perturbed the actin cytoskeleton and Ca(2+) signaling; exposure to ethyl palmitate severely affected Ca(2+) signaling. Acetaldehyde, like ethanol, promoted fusion between ZGs by the formation of ZG-ZG exocytotic complexes (between Munc18b and Syntaxin-3, SNAP23, and VAMP8), whereas ethyl palmitate and ethyl oleate reduced ZG-ZG fusion and formation of these complexes.

Conclusions: The ethanol metabolites acetaldehyde, ethyl palmitate, and ethyl oleate perturb exocytosis processes in cultured rat pancreatic acini (apical blockade, basolateral exocytosis, and fusion between ZGs). Acetaldehyde and, to a lesser degree, ethyl oleate produce many of the same pathologic effects of ethanol on CCK-8-stimulated exocytosis in pancreatic acini.
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http://dx.doi.org/10.1053/j.gastro.2012.06.011DOI Listing
September 2012

Live pancreatic acinar imaging of exocytosis using syncollin-pHluorin.

Am J Physiol Cell Physiol 2011 Jun 9;300(6):C1513-23. Epub 2011 Feb 9.

Dept. of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada.

In this report, a novel live acinar exocytosis imaging technique is described. An adenovirus was engineered, encoding for an endogenous zymogen granule (ZG) protein (syncollin) fused to pHluorin, a pH-dependent green fluorescent protein (GFP). Short-term culture of mouse acini infected with this virus permits exogenous adenoviral protein expression while retaining acinar secretory competence and cell polarity. The syncollin-pHluorin fusion protein was shown to be correctly localized to ZGs, and the pH-dependent fluorescence of pHluorin was retained. Coupled with the use of a spinning disk confocal microscope, the syncollin-pHluorin fusion protein exploits the ZG luminal pH changes that occur during exocytosis to visualize exocytic events of live acinar cells in real-time with high spatial resolution in three dimensions. Apical and basolateral exocytic events were observed on stimulation of acinar cells with maximal and supramaximal cholecystokinin concentrations, respectively. Sequential exocytic events were also observed. Coupled with the use of transgenic mice and/or adenovirus-mediated protein expression, this syncollin-pHluorin imaging method offers a superior approach to studying pancreatic acinar exocytosis. This assay can also be applied to acinar disease models to elucidate the mechanisms implicated in pancreatitis.
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http://dx.doi.org/10.1152/ajpcell.00433.2010DOI Listing
June 2011

The relative effects of habitat loss and fragmentation on population genetic variation in the red-cockaded woodpecker (Picoides borealis).

Mol Ecol 2010 Sep 7;19(17):3679-91. Epub 2010 Jul 7.

Department of Fisheries and Wildlife, Michigan State University, East Lansing, MI 48824, USA.

The relative influence of habitat loss, fragmentation and matrix heterogeneity on the viability of populations is a critical area of conservation research that remains unresolved. Using simulation modelling, we provide an analysis of the influence both patch size and patch isolation have on abundance, effective population size (N(e)) and F(ST). An individual-based, spatially explicit population model based on 15 years of field work on the red-cockaded woodpecker (Picoides borealis) was applied to different landscape configurations. The variation in landscape patterns was summarized using spatial statistics based on O-ring statistics. By regressing demographic and genetics attributes that emerged across the landscape treatments against proportion of total habitat and O-ring statistics, we show that O-ring statistics provide an explicit link between population processes, habitat area, and critical thresholds of fragmentation that affect those processes. Spatial distances among land cover classes that affect biological processes translated into critical scales at which the measures of landscape structure correlated best with genetic indices. Therefore our study infers pattern from process, which contrasts with past studies of landscape genetics. We found that population genetic structure was more strongly affected by fragmentation than population size, which suggests that examining only population size may limit recognition of fragmentation effects that erode genetic variation. If effective population size is used to set recovery goals for endangered species, then habitat fragmentation effects may be sufficiently strong to prevent evaluation of recovery based on the ratio of census:effective population size alone.
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http://dx.doi.org/10.1111/j.1365-294X.2010.04659.xDOI Listing
September 2010

Landscape evaluation in conservation: molecular sampling and habitat modeling for the Iberian lynx.

Ecol Appl 2006 Jun;16(3):1037-49

Department of Applied Biology, Doñana Biological Station, Spanish Council for Scientific Research-CSIC, Avda. María Luisa s/n 41013 Seville, Spain.

Conservation of endangered species requires comprehensive understanding of their distribution and habitat requirements, in order to implement better management strategies. Unfortunately, this understanding is often difficult to gather at the short term required by rapidly declining populations of many rare vertebrates. We present a spatial habitat modeling approach that integrates a molecular technique for species detection with landscape information to assess habitat requirements of a critically endangered mammalian carnivore, the Iberian lynx (Lynx pardinus), in a poorly known population in Spain. We formulated a set of model hypotheses for habitat selection at the spatial scale of home ranges, based on previous information on lynx requirements of space, vegetation, and prey. To obtain the required data for model selection, we designed a sampling protocol based on surveys of feces and their molecular analysis for species identification. After comparing candidate models, we selected a parsimonious one that allowed (1) reliable assessment of lynx habitat requirements at the scale of home ranges, (2) prediction of lynx distribution and potential population size, and (3) identification of landscape management priorities for habitat conservation. This model predicted that the species was more likely to occur in landscapes with a higher percentage of rocky areas and higher cover of bushes typical of mature mediterranean shrubland mosaics. Its accuracy for discriminating lynx presence was approximately 85%, indicating high predictive performance. Mapping model predictions showed that only 16% of the studied areas constitute potential habitat for lynx, even though the region is dominated by large extents of well-preserved native vegetation with low human interference. Habitat was mostly clumped in two nearby patches connected by vegetation adequate for lynx dispersal and had a capacity for 28-62 potential breeding territories. The lynx population in Sierra Morena is probably the largest persisting today, but it is still critically small for optimism about its long-term persistence. Model results suggest habitat conservation and restoration actions needed for preserving the species, including reconciliation of hunting management with preservation of mature shrubland over large areas (particularly in rocky landscapes). The approach presented here can be applied to many other species for which the ecological information needed to develop sound habitat conservation strategies is lacking.
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http://dx.doi.org/10.1890/1051-0761(2006)016[1037:leicms]2.0.co;2DOI Listing
June 2006