Buenos Aires Province Research Articles

Detection of plasma anti-lipopolysaccharide (LPS) antibodies against enterohemorrhagic Escherichia coli (EHEC) in asymptomatic kindergarten teachers from Buenos Aires province

In Argentina, hemolytic uremic syndrome (HUS) caused by EHEC has the highest incidence in the world. EHEC infection has an endemo-epidemic behavior, causing 20–30% of acute bloody diarrhea syndrome in children under 5 years old. In the period 2016–2020, 272 new cases per year were notified to the National Health Surveillance System. Multiple factors are responsible for HUS incidence in Argentina including person-to-person transmission. In order to detect possible EHEC carriers, we carried out a preliminary study of the frequency of kindergarten teachers with anti-LPS antibodies against the most prevalent EHEC serotypes in Argentina. We analyzed 61 kindergarten teachers from 26 institutions from José C. Paz district, located in the suburban area of Buenos Aires province, Argentina. Fifty-one percent of the plasma samples had antibodies against O157, O145, O121 and O103 LPS: 6.4% of the positive samples had IgM isotype (n=2), 61.3% IgG isotype (n=19) and 32.3% IgM and IgG (n=10). Given that antibodies against LPS antigens are usually short-lived specific IgM detection may indicate a recent infection. In addition, the high percentage of positive samples may indicate a frequent exposure to EHEC strains in the cohort studied, as well as the existence of a large non-symptomatic population of adults carrying pathogenic strains that could contribute to the endemic behavior through person-to-person transmission. The improvement of continuous educational programs in kindergarten institutions could be a mandatory measure to reduce HUS cases not only in Argentina but also globally.

A new species of Anisophya (Orthoptera: Tettigoniidae: Phaneropterinae) from Argentina, its ultrasound male-female communication, life history and ecology.

Anisophya arreguii sp. nov. is added as third species of the genus in Buenos Aires Province. A population living in humid meadows near La Plata, regularly observed during the last five years, was found to be different from A. punctinervis. It appears in two distinct annual generations. The male produces a continuous ultrasound calling song, to which the female responds with short signals after particular syllables. The verification of all Anisophya observations from Argentina on iNaturalist helped clarifying the distinctiveness of the new species. Some ecological aspects are briefly discussed, such as a vulnerable population in the city of La Plata.

Feline sporotrichosis due to Sporothrix globosa in the Metropolitan region of Buenos Aires: A case study

We describe here the first case of feline sporotrichosis caused by Sporothrix globosa, occurring outside the epizootic area of Buenos Aires province, Argentina. Unlike cases reported with Sporothrix brasiliensis, on this occasion there was no clinical or serological evidence of zoonotic transmission through scratches or bites from the sick cat to the attending veterinarian or the person responsible for its care. This report aimed to improve the knowledge about the pathogenic profile of S. globosa.

Bovine autosomal recessive alpha‐mannosidosis in an Aberdeen Angus herd from Argentina

AbstractAn outbreak of α‐mannosidosis in a bovine herd from Buenos Aires province is reported. Postmortem examination, histology, lectin histochemistry and electron microscopy were performed on five calves born with nervous signs. Hair samples from dams and calves were genetically analysed. The α‐mannosidase gene including exon 7 was amplified and sequenced. At postmortem examination, no gross changes were evident. Histologically, cytoplasmic neuronal vacuolation in the brain and cerebellum of the five calves, staining moderately to intensively, with lectin histochemistry was evident. Ultrastructurally, vacuoles containing finely granulated material in the cytoplasm of neurons, myelin degeneration and axonal swelling were seen in the brain. Genetic analysis revealed a heterozygous carrier state for 961T→C transition in the exon 7 of α‐mannosidosis gene of four cows, and a recessive homozygous state for 961T→C transition in the same genes in the calves analysed. This highlights the importance of identifying and removing animals carrying the α‐mannosidosis mutated gene.

Seasonal beach profile variability and short to medium-term evolution of beaches in the municipality of General Alvarado, Buenos Aires province, Argentina

Coastal erosion is a significant environmental hazard in several localities of Buenos Aires province. The aim of this study was to determinate the seasonal beach variability and short to medium-term evolution of beaches in General Alvarado Municipality, and the relationship between this evolution and coastal storms. Sandy beaches with different geomorphological characteristics and human influence, were seasonally monitored by beach profiles and sediment sampling during two periods: from 1994 to 2004, and from 2013 to 2018. Wave conditions were also analyzed to identify coastal storms. The results highlight areas with different evolution trends. Beaches in the north are accreting, while in the south they are eroding. A stable condition is observed in the center area. Seasonally, the beaches are mostly erosive in autumn and winter, and accretional in spring and summer, concurring with the cycles related to seasonal wave conditions. Except for particular exceptions, periods with intense and successive coastal storms caused significant erosion processes, sediment loss and changes in beach profile configuration. The beaches showed different response and recovery time post storm events. The findings and methods derived from this kind of studies contribute to the design of mitigation and prevention policies, and for responsible coastal planning and management.

Novel B2 mitogenomes from Continental southern Patagonia's Late Holocene: New insights into the peopling of the Southern Cone.

The main aim of this study is to discuss the migratory processes and peopling dynamics that shaped the genetic variability of populations during the settlement of the Southern Cone, through the analysis of complete mitogenomes of individuals from southern Patagonia. Complete mitogenomes were sequenced through massively parallel sequencing from two late Holocene individuals (SAC 1-1-3 and SAC 1-1-4) buried in the same chenque at Salitroso Lake Basin (Santa Cruz province, Argentina). To evaluate matrilineal phylogenetic affinities with other haplotypes, maximum likelihood and Bayesian phylogenetic reconstructions were performed, as well as a haplotype median-joining network. The mitogenomes were assigned to haplogroups B2 and B2b, exhibiting an average depth of 54X and 89X (≥1X coverage of 98.6% and 100%), and a high number of nucleotide differences among them. The phylogenetic analyses showed a relatively close relationship between the haplotype found in SAC 1-1-4 and those retrieved from a Middle Holocene individual from Laguna Chica (Buenos Aires province), and from a group of individuals from the Peruvian coast. For the SAC 1-1-3, no clear affiliations to any other haplotype were established. The large divergence between the haplotypes presented in this study suggests either a highly variable founder gene pool, or a later enrichment by frequent biological contact with other populations. Our results underline the persistence of genetic signals related to the first waves of peopling in South America, suggesting that the regional settlement of the southern end of the continent has been much more complex than initially thought.

Diachronic approach to practices associated with the use of firewood in Parque Costero del Sur and its surroundings (Buenos Aires Province, Argentina)

Diachronic approach to practices associated with the use of firewood in Parque Costero del Sur and its surroundings (Buenos Aires Province, Argentina)

High-resolution sedimentological and stratigraphic framework for the Pehuen Co Paleoichnological site, late Pleistocene, Buenos Aires, Argentina

The Pehuen Co Paleoichnological site (Buenos Aires Province, Argentina) contains one of the more diverse and well-preserved mammal and bird fossil footprint assemblages from the Late Pleistocene. The purposes of this paper were a detailed paleoenvironmental assessment of the footprint-bearing unit (middle member of the Agua Blanca Sequence) and to date key stratigraphic surfaces to constraint the temporal development of the site. A total of twenty-two detailed sedimentological sections were measured and correlated and five sediment and fossil remain samples were dated by the Optically Stimulated Luminescence (OSL) and Electron Spin Resonance (ESR) methods, respectively. The lower part of the local sequence represents dense to dilute alluvial deposits that were pedogenized. The middle part contains an alternance of sandy sheet-flood and lacustrine mudflat deposits with sand patches of eolian origin. Most of the fossil footprints with better preservation quality were recorded in the mudflats of a shallow lake sourced by unconfined fluvial currents. The participation of eolian deposits increases up section. Locally, a sandy plain of fluvial origin is developed at the top of the section. The new OSL ages along with a previous radiocarbon date led us to propose that sedimentation of footprint-bearing levels would have extended approximately between 28.5 and 12.0 ka. Reworked marine shell remains from the lowermost levels of site with fossil footprints gave considerably older analytical ages in the range of 97.6–62.5 ka, which is probably the maximum age for the middle member of the Agua Blanca Sequence. The “marine levels of Pehuen Co”, which are exposed at very low tides and contains in situ specimens of Ophiomorpha nodosa, are dated 7.0 ± 0.4 ka (OSL method). They reflect a Middle Holocene sea level rise in the area.

Histotaphonomy of a Pleistocene megamammal assemblage from Argentine Pampas

This work involves a multy-proxy approach of taphonomic features of the extinct giant ground sloth Lestodon armatus (Xenarthra, Mylodontidae). The study is based on paleohistological, mineralogical, and geochemical analyses from the Late Pleistocene Playa del Barco site (Buenos Aires Province, Argentina). Transverse thin sections of ribs and vertebrae were studied under light microscope, polarizing petrographic microscope, and scanning electron microscope (SEM), combined with chemical analysis using energy dispersive spectroscopy (EDS) and micro-X-ray diffraction (μXRD). The internal crystalline structure and mineral composition remains almost unaltered. The bone microstructure is well preserved in all the samples, although it was affected by different types of microfractures and infillings. Numerous radial microcracks were identified in the secondary osteons of all specimens evidencing wet depositional environment. The mineralogical and geochemical composition of the infillings and encrustations indicates that the enrichment with new elements was due to direct exchange with the sediments in which they were buried. Mineralogical evidence from the infillings allows to identify different diagenetic pathways; most of the skeletal elements were quickly buried in the vadose zone, while others were buried in the phreatic zone, directly or after some time immersed in a continental aquatic context. The fossildiagenetic information obtained from the Lestodon armatus fossils provides novel information to interpret and reconstruct the whole taphonomic history and the environmental and climatic conditions that favored the preservation of the Playa del Barco fossil assemblage during the end of the Last Glacial Maximum.

Superconducting Gravimeters: A Novel Tool for Validating Remote Sensing Evapotranspiration Products

The practical utility of remote sensing techniques depends on their validation with ground-truth data. Validation requires similar spatial-temporal scales for ground measurements and remote sensing resolution. Evapotranspiration (ET) estimates are commonly compared to weighing lysimeter data, which provide accurate but localized measurements. To address this limitation, we propose the use of superconducting gravimeters (SGs) to obtain ground-truth ET data at larger spatial scales. SGs measure gravity acceleration with high resolution (tenths of nm s−2) within a few hundred meters. Similar to lysimeters, gravimeters provide direct estimates of water mass changes to determine ET without disturbing the soil. To demonstrate the practical applicability of SG data, we conducted a case study in Buenos Aires Province, Argentina (Lat: −34.87, Lon: −58.14). We estimated cumulative ET values for 8-day and monthly intervals using gravity and precipitation data from the study site. Comparing these values with Moderate Resolution Imaging Spectroradiometer (MODIS)-based ET products (MOD16A2), we found a very good agreement at the monthly scale, with an RMSE of 32.6 mm month−1 (1.1 mm day−1). This study represents a step forward in the use of SGs for hydrogeological applications. The future development of lighter and smaller gravimeters is expected to further expand their use.

New light on the late Middle Miocene–Early Pliocene representatives of Lagostomus (Chinchillidae, Rodentia) from Cerro Azul Formation, Argentina

Lagostominae (Rodentia, Caviomorpha, Chinchillidae) include a single living species, the plains vizcacha Lagostomus maximus, but representatives of this subfamily are registered since the Early Miocene. The oldest record of this genus was recently extended to the late Middle Miocene in one locality of center of La Pampa Province. Previously, from levels of the Late Miocene Cerro Azul Formation in Buenos Aires and La Pampa provinces, two species of Lagostomus were recognized based on specimens from two localities, L. telenkechanum from Arroyo Chasicó (Buenos Aires Province) and L. pretrichodactyla from Salinas Grandes de Hidalgo (La Pampa Province). In the present work, new materials from these two and other localities of the Cerro Azul Formation are analyzed. This study supports the presence of both species, which had coexisted in several of the analyzed assemblages. The studied sample includes several incomplete specimens and others interpreted as juvenile individuals, which can only be determined as Lagostomus sp. Also, a similar behavior to that of the extant L. maximus (i.e., gregarious populations with fossorial habits) is proposed to explain the different representation of Lagostomus in each assemblage. In Cerro Azul Formation the presence of representatives of Lagostomus is mainly linked with levels with paleosols and accumulations by predator activity. Finally, we conclude that this genus has less biostratigraphic value than previously thought, at least for central Argentina.

Morphological, molecular and toxinological analyses of Alexandrium affine (Dinophyceae) from marine coastal waters of Buenos Aires Province (Argentina)

ABSTRACT In the framework of a monitoring program of harmful microalgae from the marine coastal waters of Buenos Aires Province to mitigate the impacts of harmful algal blooms on the aquaculture and marine life and to protect human health, a strain of Alexandrium affine (LPCc012) was isolated. Alexandrium affine is a worldwide distributed species reported as harmful algal bloom-forming, with toxin- and non-toxin-producing strains. Field and cultured materials from Buenos Aires Province were examined using light and scanning electron microscopy, morphologically and genetically (LSU rDNA partial sequencing) characterized, and compared with material from different regions worldwide. Toxin analyses using ultra-performance liquid chromatography with fluorescence detection and liquid chromatography-mass spectrometry methods failed to detect any paralytic or lipophilic shellfish toxins. This is the first record of A. affine from Argentina.

Gully development on the foredune of Pehuén Co (SW Buenos Aires Province, Argentina) and its relationship with rainfall and human activities

Understanding gully development is necessary to protect beach foredunes efficiently against gully erosion. The evolution of gullies on the foredune of Pehuén Co, Argentina, was explained using a combination of satellite images analysis and UAV models. In 16 years, the area covered by gullies increased 2011.4 m2 (5.6 times in size). The runoff due to precipitation is the major natural erosive agent affecting the active gully field, and its expansion is related to annual rainfall and the recurrence of rainy days. However, man-originated elements changed the drainage network and modified gully development, mainly by the construction of an unpaved road. The influence of the installation of Big Bags at the foredune toe, artificial nourishment, and the use of gullies as descents to the beach are also evaluated. Intervention is needed at gully incisions, mainly at the head of the catchments and early stages, particularly where the mass movement and the generation of cliffs have already begun. There is also a need to evaluate the location of road drainage to both reduce gully expansion and the creation of newer ones.

Neogene communal rodent burrow systems from central Argentina

ABSTRACT Fossil tetrapod burrows from the Cerro Azul Formation (Late Miocene-Early Pliocene) of southwestern Buenos Aires Province, Argentina, are described and interpreted. The local sedimentary sequence is composed of massive siltstone, with two interbedded calcareous palaeosols, that were deposited in a loessic plain under a semiarid climate. The burrow systems are recognised as Maneraichnus pampeanum igen. and isp. nov., an ichnotaxon that is typified by long ramps that lead to a main chamber located at bifurcation, with chambers forming at least one-third of the total tunnel/ramp volume. A rodent producer is indicated by the presence of interconnected burrow systems with a subcircular cross-section (average RDI = 0.98) and by paired, blunt, incisor traces. The large ratio of chamber volume to tunnel/ramp volume (0.45) is indicative of a communal species and a body mass ranging from 0.9 to 4.6 kg is inferred for the producer. Considering the mentioned constrains and the fossorial mammals of the Cerro Azul Formation, it is proposed that the burrow systems belonged to Lagostomus (Late Miocene-Recent). The fossil burrows also match extant L. maximus (‘vizcacha’) burrow systems in overall architecture, passive fill, and similar size of claw traces. Miocene species of Paedotherium (Notoungulate) is discussed as an alternative potential digger.http://zoobank.org:act:C3588BE1-BAAF-46D7-92FA-0ADEF295AED3 http://zoobank.org:act:2A9F3301-9EC8-4FD1-B875-078CD9324049

Water governance challenges at a local level: implementation of the OECD Water Governance Indicator Framework in the General Pueyrredon Municipality, Buenos Aires Province, Argentina

Abstract Considering that the current water crisis is largely a governance crisis, improving water governance will help to address current and future water challenges. Water governance is defined as the range of political, institutional and administrative rules, practices and processes through which decisions are taken and implemented, stakeholders can articulate their interests and have their concerns considered, and decision makers are held accountable for water management. The Water Governance Principles proposed by the Organisation for Economic Co-operation and Development (OECD) contribute to the creation of tangible public policies oriented toward effectiveness, efficiency, reliability and participation. The aim of this research is to apply the OECD Water Governance Indicator Framework at a local level and to identify gaps and challenges for water governance in the General Pueyrredon Municipality (GPM), Buenos Aires Province (BAP), Argentina. This framework was used as a diagnostic tool to assess water governance policy frameworks (what), institutions (who) and instruments (how). In general terms, there is a robust legal framework, there are enforcement institutions regarding water management and there is a good connection with them. However, the main challenges identified were in the ‘how’, since most of the instruments are partly or not implemented.

First record of Hyperphyscia coralloides (L.) Scutari growing on PET plastic within a fruit crops plot and its implications

Abstract In a fruit crop located in the Lujan district (Buenos Aires province, Argentina), we exposed plastic bottles to the environment for three years. We explored microplastics’ presence on thalli. Out of the potential five lichen species only one grew: Hyperphyscia coralloides. Microplastic particles were observed on the thalli. The present work represents the first record of H. coralloides growing on PET plastic. Considering the largest thalli size recorded, the results of the growth rate are similar in an average to those recorded for fruticose species. Finally, our results suggest that the contact of H. coralloides with microplastics may be a potential pathway for the incorporation of microplastics into ecosystems.

The last horned armadillos: phylogeny and decline of Peltephilidae (Xenarthra, Cingulata)

AbstractPeltephilidae (Xenarthra, Cingulata) is an ancient lineage of medium–large‐sized ‘armadillos’ from South America, characterized by chisel‐shaped molariforms, a U‐shaped dental arcade, and cephalic osteoderms modified into hornlike structures. Although the biochron of the group extends from the early Eocene to the Late Miocene, the most abundant and complete records come from the Early Miocene of Patagonia. Remains from the Late Miocene are very scarce, and the last records of the group are from the Chasicoan Stage (Tortonian). The only taxon known from this interval is Epipeltephilus kanti from the Arroyo Chasicó Formation (9.23 ± 0.09 Ma; Buenos Aires Province, Argentina), a species previously represented only by a few isolated osteoderms. Here we report new remains assigned to E. kanti from the Late Miocene of Loma de Las Tapias Formation (c. 9.0–7.8 Ma; San Juan Province, Argentina), including a hemimandible and several fixed and mobile osteoderms. These new specimens constitute the youngest record of Peltephilidae. The inclusion of E. kanti within Epipeltephilus and the monophyly of the genera Peltephilus and Epipeltephilus are corroborated for the first time through a cladistic analysis. The decline and eventual disappearance of this ‘armadillo’ group in the Late Miocene is chronologically coincident with the replacement of subtropical/tropical environments by more open and arid ones and with the proliferation of other large armadillos such as Vetelia, Macrochorobates, and Macroeuphractus.

Flower and fruit formation of Hexachlamys edulis in Buenos Aires, Argentina

Hexachlamys edulis (O. Berg) Kausel & D. Legrand, “ubajay” is a Myrtaceae species autochthonous of South America. It is a prominent species, with potentially nutraceutical fruits, leaves and other organs with important uses with great benefits for human health and new alternatives for production systems. Levels of polyphenols and pigments together with the antioxidant activity allow us to consider H. edulis fruit as a functional food. Nevertheless, there are not yet enough scientific studies on its physiology and productive capacity. The objectives of this work were i) describe the development of flower bud to mature fruit of H. edulis in the agro ecological conditions of the locality of Moreno (Buenos Aires provinc ); ii) study of pollination methods; iii), evaluate the floral phenology evolution and iv) compare the climatic conditions of Moreno (Buenos Aires province) with Federación (Entre Ríos province), which is the original place of the plants. Nine floral phenological stages (B, C, D, E, F1; F2, F3, G, H) have been recognized during the blooming period. Results of pollination treatments were very diverse. SP and CPS did not produce fruits while OP and CPA produced 5.6% and 20.0% respectively. Climatic condition of Moreno was very appropriate during the year 2018, when the levels of flower anthesis and fruit set were the highest. Fruits ripened during the last three weeks of December, without significant differences between 2019 and 2020. Despite the climatic differences between the site of origin and the experimental plot, it can be confirmed that the biological cycle of Hexachlamys edulis was perfectly fulfilled without anthropic intervention in the Moreno site, confirming that this species presents a high plasticity and that fruit production could be incremented with appropriate cultural practices.

The Spanish Enlightenment and Happiness Economics. The case of Seville’s Economic Society of Friends of the Country and its project to trade meat salting with Buenos Aires Province (1778)

The Enlightened Movement in Spain is widely known for its modernizing effort and its economic and social reform projects in Spain in the 18th and 19th centuries. In line with the European Enlightenment, the ideals of classical liberalism and utilitarianism began to spread hand in hand with the enlightened intellectuals as a paradigm towards the well-being of the people. The anthropocentric turn of the Enlightenment brought with it not only the struggle for the rights of man and the consequent evolution of European absolute monarchies towards enlightened despotism, but also the evolution of the very perception of wealth, well-being and happiness of the society. Thanks to the works of Adam Smith, Thomas Malthus or Jeremy Bentham, the roots of the Happiness Economics can be traced back to the 18th century through the association they made between the economic development of society and the level of happiness. This paper analyzes the project of the Royal Sevillian Economic Society of Friends of the Country for the salted meat trade with the province of Buenos Aires as a case study of the connection between economic development, well-being and happiness in the Spanish Enlightenment through the study of the transcripts of sessions collected in the Libro de Actas No. 1 (1775-1780) and the copies of letters collected in the Book of Correspondence of the Society, as well such as the loose papers available in the Municipal Archive of Seville.

Presence of SARS-CoV-2 in urban effluents in south-east Buenos Aires, Argentina, May 2020 to March 2022.

To implement and evaluate the use of wastewater sampling for detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in two coastal districts of Buenos Aires Province, Argentina. In General Pueyrredon district, 400 mL of wastewater samples were taken with an automatic sampler for 24 hours, while in Pinamar district, 20 L in total (2.2 L at 20-minute intervals) were taken. Samples were collected once a week. The samples were concentrated based on flocculation using polyaluminum chloride. RNA purification and target gene amplification and detection were performed using reverse transcription polymerase chain reaction for clinical diagnosis of human nasopharyngeal swabs. In both districts, the presence of SARS-CoV-2 was detected in wastewater. In General Pueyrredon, SARS-CoV-2 was detected in epidemiological week 28, 2020, which was 20 days before the start of an increase in coronavirus virus disease 2019 (COVID-19) cases in the first wave (epidemiological week 31) and 9 weeks before the maximum number of laboratory-confirmed COVID-19 cases was recorded. In Pinamar district, the virus genome was detected in epidemiological week 51, 2020 but it was not possible to carry out the sampling again until epidemiological week 4, 2022, when viral circulation was again detected. It was possible to detect SARS-CoV-2 virus genome in wastewater, demonstrating the usefulness of the application of wastewater epidemiology for long-term SARS-CoV-2 detection and monitoring.