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Copyright of Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Questions: What is the role of native and domestic herbivores in native–alien vegetation changes in sub‐Antarctic forests? Does herbivory suppression increase native while reducing alien species diversity? Location: Central–eastern Tierra del Fuego Island, Argentina. Methods: In four sites, we set up three different treatments: excluded grazing by livestock (cattle), by livestock and native (guanaco) herbivores, and grazed control plots in Nothofagus antarctica forests. We then monitored the dynamics of understorey native and alien plants (species richness, abundance) of dicots, monocots, and ferns over 6 years. Generalized Linear Mixed Models were used to determine the effects of herbivore exclusion and time on species richness and abundance. In addition, we calculated the abundance rate of change to quantify temporal dynamics. Results: Overall species richness did not change in the exclusion plots, but native and alien abundances were affected by herbivory and time since exclusion. The abundance of native monocots changed after herbivore exclusion, increasing its dominance significantly inside exclusion plots. However, the cessation of herbivory did not reduce alien species in general. Only alien dicots significantly declined in the livestock exclusion treatment. Further, we found that the two dominant alien grass species (Holcus lanatus and Poa pratensis) respond differently to grazing exclusion, and their response was modulated by forest basal area. Conclusions: Our results indicate that cattle and guanaco grazing had variable effects on native and alien plants, and that herbivore exclusion has a substantially positive effect on native grasses. However, the magnitude of temporal changes was more significant for vegetation richness and abundance than the effect of exclusion treatments. Herbivore exclusions can initiate a rapid recovery of compositional attributes of native vegetation in N. antarctica forests grazed by livestock. [ABSTRACT FROM AUTHOR]

Copyright of Plurentes is the property of Universidad Nacional de La Plata and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Atrio: Revista de Historia del Arte is the property of Atrio. Revista de Historia del Arte - Universidad Pablo de Olavide and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The practice of enforced disappearances fundamentally alters memorialisation rituals as relatives do not have a body to localise mourning as is possible with processes of death. Families in the Southern Cone of South America (Chile/Argentina) have sought new ways to remember the dictatorship missing who remain in a liminal space between life and death. As a vehicle to represent public grief, photography became vital; families marched with photographs of their disappeared relatives on placards or pinned to their chests. Studies on the importance of photography and disappearance have come some way in elucidating the photographic medium's unique role of in representing the disappeared. However, little scholarship has looked at the role of photography and new media in these histories. Charting the use of photographs in Chile and Argentina to represent the disappeared and their families' grief, this article engages with their suspended mourning drawing on content and visual analysis alongside expert interview data. By analysing two websites that reproduce photographs of the disappeared: and , the article looks at the use of photography in the digital ecology. Both sites show photography's continued importance for rituals of remembrance and to demand accountability in the present and for the future. [ABSTRACT FROM AUTHOR]

Background: Autosomal recessive (AR) complete IRF8 deficiency is a rare severe inborn error of immunity underlying an absence of blood myeloid mononuclear cells, intracerebral calcifications, and multiple infections. Only three unrelated patients have been reported. Materials and Methods: We studied an Argentinian child with multiple infectious diseases and severe pulmonary alveolar proteinosis (PAP). We performed whole-exome sequencing (WES) and characterized his condition by genetic, immunological, and clinical means. Results: The patient was born and lived in Argentina. He had a history of viral pulmonary diseases, disseminated disease due to bacillus Calmette-Guérin (BCG), PAP, and cerebral calcifications. He died at the age of 10 months from refractory PAP. WES identified two compound heterozygous variants in IRF8: c.55del and p.R111*. In an overexpression system, the p.R111* cDNA was loss-of-expression, whereas the c.55del cDNA yielded a protein with a slightly lower molecular weight than the wild-type protein. The mutagenesis of methionine residues downstream from c.55del revealed a re-initiation of translation. However, both variants were loss-of-function in a luciferase assay, suggesting that the patient had AR complete IRF8 deficiency. The patient had no blood monocytes or dendritic cells, associated with neutrophilia, and normal counts of NK and other lymphoid cell subsets. Conclusion: We describe the fourth patient with AR complete IRF8 deficiency. This diagnosis should be considered in children with PAP, which is probably due to the defective development or function of alveolar macrophages. [ABSTRACT FROM AUTHOR]

Background: The increase of excess weight around the world is progressive and sustained in children. This is the most prevalent form of malnutrition in this population and they represent the major public health problem in developed and developing countries. The aim of this study was to analyze the magnitude of change in thinness and excess weight prevalence in 4-7 years-old schoolchildren from Jujuy (Argentina), between 1996 and 2015 and to examine the association according to sex and school location.Methods: Cross-sectional study. Data was obtained from databases of School Health programs and it is representative of the city school population. For the analysis, 31,014 schoolchildren between 4 and 7 years old were evaluated, 20,224 from the first period (1996-2001) and 10,790 from the second (2010-2015). The city was partitioned in three different areas determined by the rivers that cross it. Nutritional status was determined by BMI for age with the criteria suggested by the International Obesity Task Force. The percentage of malnutrition change between periods was calculated and a binomial regression model was adjusted.Results: Between periods, a significant (p-value< 0.0001) increase in the prevalence of overweight from 15.1% (CI 14.6-15.6%) to 18.1% (CI 17.4-18.8%) and obesity from 5% (CI 4.7-5.3) to 10.7% (CI 10.1-11.3%), and a decrease of thinness prevalence from 6.3% (CI 6.0-6.7%) to 4.7% (CI 4.3-5.1%) were observed. The percentage of change in the prevalence of obesity was very high in all areas and in both sexes (103.5% girls; 125.6% in boys), being higher in the south for girls (122.4%) and in the north for boys (158.8%). Besides, being a boy was inversely associated with the presence of excess weight and, as the age increases, the presence of obesity does it too. By analyzing the effect of the school location, the south and north zones had an inverse association with the presence of obesity. The period has a direct association with the presence of excess weight.Conclusion: The study contributes with valuable information on the magnitude of the increase in obesity in schoolchildren and suggests a possible correlation with sex and spatial distribution in the capital city of Jujuy. [ABSTRACT FROM AUTHOR]

Copyright of Enfermería Neonatal is the property of Fundacion para la Salud Materno Infantil (FUNDASAMIN) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Streptococcus agalactiae is a pathogen-associated to bovine mastitis, a health disorder responsible for significant economic losses in the dairy industry. Antimicrobial therapy remains the main strategy for the control of this bacterium in dairy herds and human In order to get insight on molecular characteristics of S. agalactiae strains circulating among Argentinean cattle with mastitis, we received 1500 samples from 56 dairy farms between 2016 and 2019. We recovered 56 S. agalactiae isolates and characterized them in relation to serotypes, virulence genes, and antimicrobial susceptibility. Serotypes III and II were the most prevalent ones (46% and 41%, respectively), followed by Ia (7%). In relation to the 13 virulence genes screened in this study, the genes spb1, hylB, cylE , and PI-2b were present in all the isolates, meanwhile, bca , cpsA , and rib were detected in different frequencies, 36%, 96%, and 59%, respectively. On the other hand, bac, hvgA, lmb , PI-1, PI-2a, and scpB genes could not be detected in any of the isolates. Disk diffusion method against a panel of eight antimicrobial agents showed an important number of strains resistant simultaneously to five antibiotics. We also detected several resistance-encoding genes, tet(M), tet(O), ermB, aphA3 , and lnu(B) (9%, 50%, 32%, 32%, and 5%, respectively). The results here presented are the first molecular data on S. agalactiae isolates causing bovine mastitis in Argentina and provide a foundation for the development of diagnostic, prophylactic, and therapeutic methods, including the perspective of a vaccine. [ABSTRACT FROM AUTHOR]

BACKGROUND: The Berberis microphylla (calafate) is an evergreen shrub considered a non-timber product from the Patagonian forest, relevant for the diversification of agrifood production, particularly interesting since its black–blue fruits are extremely rich in phenolic compounds. OBJECTIVE: The main objectives were to: (1) quantify the variability of fruit traits, anthocyanin content, efficiency of the reproductive shoots and leaf nutrient content within the set of 34 B. microphylla wild accessions from Tierra del Fuego Island, Argentina, (2) calculate the coefficients of correlation between variables and (3) detect relationships between the genotypes. METHODS: Plants growing near Ushuaia city (n = 12), bordering Fagnano lake (n = 12) and central area of the Tierra del Fuego Island (n = 10) were selected. RESULTS: A significant variability in fruit traits, anthocyanin content and the efficiency of reproductive shoots among and within the three populations was assessed, a result with great relevance for breeding purposes. Phenotypic plasticity was related with the environmental conditions, i.e. air temperatures for each population during the three monitored growing seasons. CONCLUSIONS: Overall, results indicate that yearly environmental factors play a relevant role in phenotypic variation of both individual plants and populations, thus confirming the complexity of wild species evolution and domestication processes. [ABSTRACT FROM AUTHOR]

Copyright of Anuario del Instituto de Historia Argentina is the property of Universidad Nacional de La Plata and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We analyzed 391 samples from 12 Argentinian populations from the Center-West, East and North-West regions with the Illumina Human Exome Beadchip v1.0 (HumanExome-12v1-A). We did Principal Components analysis to infer patterns of populational divergence and migrations. We identified proportions and patterns of European, African and Native American ancestry and found a correlation between distance to Buenos Aires and proportion of Native American ancestry, where the highest proportion corresponds to the Northernmost populations, which is also the furthest from the Argentinian capital. Most of the European sources are from a South European origin, matching historical records, and we see two different Native American components, one that spreads all over Argentina and another specifically Andean. The highest percentages of African ancestry were in the Center West of Argentina, where the old trade routes took the slaves from Buenos Aires to Chile and Peru. Subcontinentaly, sources of this African component are represented by both West Africa and groups influenced by the Bantu expansion, the second slightly higher than the first, unlike North America and the Caribbean, where the main source is West Africa. This is reasonable, considering that a large proportion of the ships arriving at the Southern Hemisphere came from Mozambique, Loango and Angola. [ABSTRACT FROM AUTHOR]

Background Familial hypercholesterolemia (FH) is a genetic disorder characterized by elevated low-density lipoprotein cholesterol and early cardiovascular disease. As cardiovascular disease is a leading cause of mortality in Argentina, early identification of patients with FH is of great public health importance. Objective The aim of our study was to identify families with FH and to approximate to the characterization of the genetic spectrum mutations of FH in Argentina. Methods Thirty-three not related index cases were selected with clinical diagnosis of FH. Genetic analysis was performed by sequencing, multiplex ligation-dependent probe amplification, and bioinformatics tools. Results Twenty genetic variants were identified among 24 cases (73%), 95% on the low-density lipoprotein receptor gene. The only variant on APOB was the R3527Q. Four were novel variants: c.-135C>A, c.170A>C p.(Asp57Ala), c.684G>C p.(Glu228Asp), and c.1895A>T p.(Asn632Ile); the bioinformatics’ analysis revealed clear destabilizing effects for 2 of them. The exon 14 presented the highest number of variants (32%). Four variants were observed in more than 1 case and the c.2043C>A p.(Cys681*) was carried by 18% of index cases. Two true homozygotes, 3 compound heterozygotes, and 1 double heterozygote were identified. Conclusion This study characterizes for the first time in Argentina genetic variants associated with FH and suggest that the allelic heterogeneity of the FH in the country could have 1 relative common low-density lipoprotein receptor mutation. This knowledge is important for the genotype–phenotype correlation and for optimizing both cholesterol-lowering therapies and mutational analysis protocols. In addition, these data contribute to the understanding of the molecular basis of FH in Argentina. [ABSTRACT FROM AUTHOR]

• Wildfires are exclusively human caused in Tierra del Fuego, Argentina. • Tree regeneration is sparse post-fire. • Grassland species dominate understory species assemblages in burned forests. • Exotic plant cover and richness increase substantially post-fire and remain high. • Native plant cover does not recover to pre-fire levels 12 years after wildfire. Historically, wildfires have occurred infrequently in the Subantarctic forests on the island of Tierra del Fuego in southern Argentina: wildfires on the landscape are sporadic and exclusively human-caused. As a result of this, post-fire effects on native vegetation are largely unknown. In November of 2008, a wildfire started near a sawmill in the central part of the island. Six pre-established research plots located in Nothofagus antarctica (ñire) dominated forests burned, impacting a long-term study of understory vegetation dynamics. In 2008 (pre-fire), two 10 m long permanent transects were established per plot (n = 12), where we evaluated species richness and plant cover using a point intersection method at 20 cm intervals, resulting in 50 points per transect. After the fire, we continued sampling to evaluate post-fire understory response in burned and unburned plots. The first post-fire sampling occurred in January 2009, and was repeated semi-annually in burned and unburned plots (2010–2014, 2016, 2018, 2020, and 2021). Data were analyzed using GLMMs (Generalized Linear Mixed Models) and multivariate analyses (Nonmetric Multidimensional Scaling, Multi-Response Permutation Procedures). Total species richness and cover decreased the year following the fire, but recovered by 2010, eventually surpassing pre-fire levels. Increases in species diversity were due principally to an increase in exotic species richness (F = 4.73; p < 0.001) and cover (F = 51.59; p < 0.001). For native species, richness followed the same trend as total vegetation, but cover decreased drastically following the fire (F = 19.77; p < 0.001) and had not recovered to pre-fire levels by 2021. MRPP revealed that plant assemblage in burned plots differed from those in unburned plots the season following the fire (p < 0.001) and still differed 7–12 years post-fire (p < 0.001). Wildfire in Tierra del Fuego produces changes in understory dynamics that create non-forest plant assemblages dominated by exotic species; these changes last many years and pose a significant threat to the forests and native plant species of the island. Without active restoration, forests impacted by wildfire may be permanently lost along with the ecosystem services and habitat they provide. [ABSTRACT FROM AUTHOR]

Shiga toxin-producing Escherichia coli (STEC) is a foodborne pathogen responsible for severe disease in humans such as hemolytic uremic syndrome (HUS) and cattle, the principal reservoir. Identification of the clones/lineages is important as several characteristics, among them propensity to cause disease varies with STEC phylogenetic origin. At present, we do not know what STEC clones, especially of non-O157:H7, are circulating in Argentina. To fill this knowledge gap we assessed the genetic diversity of STEC strains isolated in Argentina from various sources, mostly cattle and food, using multilocus sequence typing (MLST). Our objectives were to determine the phylogenetic relationships among strains and to compare them with strains from different geographic origins, especially with those from clinical human cases, in order to evaluate their potential health risk. A total of 59 STEC isolates from 41 serotypes were characterized by MLST. Analysis using EcMLST database identified 38 sequence types (ST), 17 (45%) of which were new STs detected in 18 serotypes. Fifteen out of 38 STs identified were grouped into 11 clonal groups (CGs) and, 23 not grouped in any of the defined CGs. Different STs were found in the same serotype. Results highlighted a high degree of phylogenetic heterogeneity among Argentinean strains and they showed that several cattle and food isolates belonged to the same STs that are commonly associated with clinical human cases in several geographical areas. STEC is a significant public health concern. Argentina has the highest incidence of HUS in the world and this study provides the first data about which STEC clones are circulating. Data showed that most of them might pose a serious zoonotic risk and this information is important for developing public health initiatives. However, the actual potential risk will be defined by the virulence profiles, which may differ among isolates belonging to the same ST. [ABSTRACT FROM AUTHOR]

A total of 73 Shiga toxin-producing Escherichia coli ( STEC) isolates, belonging to 25 serotypes and isolated from raw products in Argentina, were examined for the occurrence of genes responsible for bacterial adhesions to intestine, ehaA ( EHEC autotransporter), lpf AO113 (long polar fimbriae), sab ( STEC autotransporter [ AT] contributing to biofilm formation), ecpA ( E. coli common pilus), hcpA (haemorrhagic coli pilus), elfA ( E. coli laminin-binding fimbriae), sfpA (sorbitol-fermenting EHEC O157 fimbriae plasmid-encoded) and of the toxigenic gene cdt-V (cytolethal distending toxin). Our study showed different adhesin profiles that are not linked to one specific serotype and that all analysed isolates possess, besides stx genes, some adherence genes. Several of the isolates contained also multiple toxin genes. The results of the present work alert the presence of genes coding for additional adhesins and cdt-V toxin in LEE-negative STEC strains that occur in foods, and this traits could increase their pathogenic potential. Significance and Impact of the Study Meat products are one of the main vehicles of Shiga toxin-producing E. coli, and the presence of genes coding for additional adhesins and toxins could increase their pathogenic potential. There is a need for a more detailed characterization of the strains in regard to these extra virulence factors. [ABSTRACT FROM AUTHOR]

Shiga toxin-producing Escherichia coli (STEC) causes serious human illness such as hemolytic uremic syndrome (HUS). Argentina has the world's highest rate of this syndrome, which is the leading cause of acute renal failure among children. E. coli O157:H7 is the most common cause of HUS, but a substantial and growing proportion of this illness is caused by infection due to non-O157 strains. Multiple-locus variable-number tandem repeat analysis (MLVA) has become an established technique to subtype STEC. This review will address the use of routine STEC subtyping by MLVA in order to type this group of isolates and to get insight into the genetic diversity of native STEC. With regard to these objectives we modified and adapted two MLVA protocols, one exclusive for O157 and the other, a generic E. coli assay. A total of 202 STEC isolates, from different sources and corresponding to 20 serotypes, have been MLVA genotyped in our laboratory. In our experience, MLVA constitutes a very sensitive tool and enables us to perform an efficient STEC subtyping. The diversity found in many serotypes may be useful for future epidemiological studies of STEC clonality, applied to O157 as well as to non-O157 isolates. [ABSTRACT FROM AUTHOR]

Detailed descriptions of morphological features, morphometrics, neurocranium anatomy, clasper structure and egg case descriptions are provided for the thickbody skate Amblyraja frerichsi; a rare, deep-water species from Chile, Argentina and Falkland Islands. The species diagnosis is complemented from new observations and aspects such as colour, size and distribution are described. Geographic and bathymetric distributional ranges are discussed as relevant features of this taxons biology. Additionally, the conservation status is assessed including bycatch records from Chilean fisheries. [ABSTRACT FROM AUTHOR]

The Lesser Rhea (Rhea pennata pennata) has suffered a marked decline in numbers over recent decades, probably mainly as a result of livestock production and overhunting. Our aim was to investigate the factors that determine the distribution of Lesser Rheas in southern Patagonia and to generate a predictive regional distribution map. We surveyed 8000 km of roads and sighted 795 Lesser Rhea individuals or flocks. We also estimated environmental predictors from remotely sensed data and analysed the occurrence of Lesser Rheas in relation to these predictors. The predictors we examined were associated with four hypotheses explaining the distribution of Lesser Rheas: the persecution by ranchers, primary productivity, topography, and anthropogenic disturbance hypotheses. We built models for each hypothesis. Our results suggest that the distribution of Lesser Rheas is not negatively affected by persecution by ranchers, as the species is more abundant in areas with high stocking levels of sheep, but is positively influenced by primary productivity and negatively by the proximity of human habitation. The resulting distribution map can be used as a management tool for government agencies and highlights the conservation priorities for managing this declining and emblematic species. [ABSTRACT FROM AUTHOR]

A species distribution may be determined by its responses to patterns of human disturbance as well as by its habitat preferences. Here we investigate the distribution of the Upland Goose Chloephaga picta, which has been historically persecuted by farmers and ranchers in Patagonia because it feeds on crops and pastures and is assumed to compete with sheep for forage. We assess whether its current breeding distribution is shaped by persecution by ranchers or whether it can be better explained by differences in habitat primary productivity and preference for wetlands, or by other anthropogenic disturbances not associated with ranching. We built species distribution models to examine the relative effect of environmental and anthropogenic predictors on the regional distribution of Upland Goose. We performed vehicle surveys in the province of Santa Cruz, Argentina, in two years, surveying 8000 km of roads and recording 6492 Geese. Generalized additive models were used to model the presence/absence of Geese in 1-km cells. The models suggested that Upland Goose distribution is not currently affected by rancher control, as the species is more abundant in areas with high sheep stocking levels, but it is positively influenced by primary productivity and negatively influenced by urban areas. Anthropogenic disturbance caused by urban areas and oil extraction camps had a greater impact in limiting the species distribution than sheep ranching. [ABSTRACT FROM AUTHOR]

The Guanaco ( Lama guanicoe) has suffered a progressive decline in numbers because of unregulated hunting and poaching by an assumed competition with sheep. Inadequate livestock management, including keeping sheep numbers above carrying capacity, has led to a degradation of the Patagonian steppe. Recently, interest has grown towards a reduction in sheep density and diversification of extractive activities. Guanaco populations could be potentially amenable to a number of sustainable uses. Our aim was to investigate the factors that determine guanaco distribution in southern Argentine Patagonia and to generate a predictive cartography at the regional scale. We hypothesized that guanaco distribution could be determined by primary productivity, terrain ruggedness, human disturbance and poaching, and competition with livestock. Guanaco surveys were performed from vehicles using a road survey method. To analyze the relationship between guanaco occurrence and potential predictors we built Generalized Additive Models (GAMs) using a binomial error and a logistic link. We found that guanaco occurrence increased in the less productive and remote areas, far from cities and oil camps, and decreased in regions with high sheep density. These results suggest that guanacos tend to occur where human pressure is lower. One way to promote guanaco conservation would be to highlight the economic value of guanacos under the regulations imposed by a sustainable exploitation of their populations. The predictive models developed here could be a useful tool for the implementation of conservation and management programs at the regional scale. [ABSTRACT FROM AUTHOR]

Abstract: Although serotype O157:H7 has been implicated in most cases of haemolytic-uraemic syndrome (HUS), there is growing concern about non-O157 serotypes of verocytotoxigenic Escherichia coli (VTEC). Multiple-locus variable-number tandem repeat analysis (MLVA) has been focused on the specific typing of O157:H7 isolates, but recently, a generic MLVA assay for E. coli and Shigella has been developed. We performed a study of the polymorphism in 7 generic VNTR loci both in VTEC O157:H7 and non-O157 isolates from Argentina, in order to asses the ability of the method to type this group of isolates and to get insight into their genetic diversity. Sixty-four isolates from cattle, patients with diarrhoea, and contaminated food belonging to 8 different serotypes were studied. All of them could be typed by this method and revealed 41 different MLVA genotypes. The MLVA dendrogram showed 2 main clusters which corresponded to O157:H7 and non-O157, respectively. Our results confirm the suitability of this MLVA method for analyzing VTEC isolates belonging to several serotypes, both O157:H7 as well as non-O157, highlight the genetic variability of the O157:H7 serotype and the need of additonal research in order to find more VNTR loci that could allow a higher discrimination among non-O157 VTEC. [Copyright &y& Elsevier]

Copyright of Canadian Journal of Zoology is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This work comes up from a revision of several studies on weeds in the Alto Valle of Río Negro and Neuquén, the common aim was to know -from sociological and ecological point of view- about the vegetation growing along roadsides, and in cultivated areas of the region dedicated to fruit and vegetable farming. Thus the sintaxons included here are those which have been registered up to the present like a form to order and guide to those who make similar work. They are ordered in a sintaxonomical schema with phytosociological, ecological and chorological references. [ABSTRACT FROM AUTHOR]

During recent years, predictive modelling techniques have been increasingly used to identify regional patterns of species spatial occurrence, to explore species–habitat relationships and to aid in biodiversity conservation. In the case of birds, predictive modelling has been mainly applied to the study of species with little variable interannual patterns of spatial occurrence (e.g. year-round resident species or migratory species in their breeding grounds showing territorial behaviour). We used predictive models to analyse the factors that determine broad-scale patterns of occurrence and abundance of wintering Swainson's hawks ( Buteo swainsoni). This species has been the focus of field monitoring in its wintering ground in Argentina due to massive pesticide poisoning of thousands of individuals during the 1990s, but its unpredictable pattern of spatial distribution and the uncertainty about the current wintering area occupied by hawks led to discontinuing such field monitoring. Data on the presence and abundance of hawks were recorded in 30 × 30 km squares ( n = 115) surveyed during three austral summers (2001–03). Sixteen land-use/land-cover, topography, and Normalized Difference Vegetation Index (NDVI) variables were used as predictors to build generalized additive models (GAMs). Both occurrence and abundance models showed a good predictive ability. Land use, altitude, and NDVI during spring previous to the arrival of hawks to wintering areas were good predictors of the distribution of Swainson's hawks in the Argentine pampas, but only land use and NDVI were entered into the model of abundance of the species in the region. The predictive cartography developed from the models allowed us to identify the current wintering area of Swainson's hawks in the Argentine pampas. The highest occurrence probability and relative abundances for the species were predicted for a broad area of south-eastern pampas that has been overlooked so far and where neither field research nor conservation efforts aiming to prevent massive mortalities has been established. [ABSTRACT FROM AUTHOR]

Aiming to study different poplar clones behaviour in the Andean Valley of Barreal, in the province of San Juan, Argentina, in 1995 a trial was set with the following clones: 7 Populus x canadensis: Cima, Fogolino, Giorgione, Schiavone, Conti 12, I-214, Veronese, and 7 Populus x deltoides: Harvard, Fierolo, I-72, 67/67, 71/67, Catfish 2 and Catfish 5. The site is placed at 31°36′55″ S and 69°27′30″ W and a height of 1.628 m above sea level. Soil is of alluvium sediment; medium texture with middle size rolling stones, beginning at 70 cm below the surface. Plantation order was settled at 5 x 2.5 m and irrigation by surface furrows. Periodically dasometric data was taken of breast height diameter (BDH) of all individuals and total height of trees of the average diameter for each clone. Also observed was the health development of each plant mainly to establish the presence or absence of pests and diseases like Poplar Borer and Septoria Canker. Results up to date show that higher wood production expressed in m³/ha are: Schiavone, I-214, Veronese, Conti 12 and Giorgione [ABSTRACT FROM AUTHOR]

The Province of Mendoza is located in the Mid-Western part of Argentina with an extension of 150.830 km². There all agrarian and forestry activities are concentrated in a 3% of its territory which is able to be irrigated. On the West side part of the province by the border with Republic of Chile appears the mountain ridge (Cordillera de Los Andes) which is a part of the fitogeographical region called Andean Desert. It extents for over 500 km with an average width of 100 km. This work is aimed to evaluate survival and behaviors of different species of conifers in the mountainous country side of Mendoza. To do so experimental plots were installed in Yaucha dam, placed in San Carlos department at 34°00′ S and 69°07′ W, at an altitude of 1213 mosl. Species on test were Pinus pinea L., Pinus halepensis Mill., and Cupressus arizonica Greene. For the experience plants of approximately 0.70 m height were installed at a definite plantation distance of 3 x 3 m with surface irrigation stream water by furrows. Periodically dasometric data is taken about diameter, chest height of every plant, total average height of trees of each specie, registering failures and sanitary situation. Results obtained at the age of 17 years are: Pinus pinea: average diameter 17 cm, height 6.60 m, failure 22.5%; Pinus halepensis: average diameter 16 cm, height 8.60 m, failure 12.2%; Cupressus arizonica: average diameter 20 cm, height 7.75 m, failure 18.1%. It is to be noted that Pinus pinea presents 6% of low height forked branches. All species are in good sanitary shape not registering any pests or diseases affecting the experiment up to date. [ABSTRACT FROM AUTHOR]

The Forestry Institute from Faculty of Agronomy Sciences of the Universidad Nacional de Cuyo (República Argentina) has introduced poplar clones from different origens to evaluate their behaviour against biotic and abiotic agents, to widen the known genetic base as well as to improve the volumetric average produced by the commercial plantations in the area. Following this line of research, in 1996 a trial was installed in an agro-forestry development in the Departament of San Carlos, Province of Mendoza at 33°46′ S, 69°02′ W, and at 940 m above sea level. Ten Poplar Clones were evaluated: 4 P. x deltoides (Stoneville 124, EEA Delta 107/68, INTA 69/69, Fierolo) and 6 P. x canadensis (El Campeador, Neva, Luisa Avanzo, B. L. Constanzo, I-42, I-455) which were placed in plots of 9 plants each, at random with 4 replicates. Distance of plantation was 4 x 6 m. Yearly measurements were made of diameter at breast height (DBH), and total height of trees, also there were periodic registers of sanitary situation particularly referred to the presence of cancrosis attacks. The higher volume in wood production per hectare was given by Stoneville 124; 322 m³/ha, EEA Delta 107/68: 293 m³/ha, INTA 69/69: 285 m³/ha and Fierolo: 239 m³/ha. The Luisa Avanzo clone showed a great susceptibility to cancrosis, which provoked a high percentage of loss of trees during the first three year, fact which was repeated by the rest of the euramerican clones on a lower scale. Conclusion: the best behaviour under trial conditions was given by: Stoneville 124, EEA Delta 107/68 and INTA 69/69. [ABSTRACT FROM AUTHOR]

In this paper we show how new technologies can be incorporated from the gathering of field data on wildlife distribution to the final stage of producing distribution maps. We describe an integrated framework for conducting wildlife censuses to obtain data to build predictive models of species distribution that when integrated in a GIS will produce a distribution map. Field data can be obtained with greater accuracy and at lower costs using a combination of Global Positioning System, Personal Digital Assistant, and specific wildlife recording software. Sampling design benefits from previous knowledge of environmental variability that can be obtained from free remote sensing data. Environmental predictors derived from this remote sensing information alone, combined with automatic procedures for predictor selection and model fitting, can render cost-effective predictive distribution models for wildlife. We show an example with guanaco distribution in the Patagonian steppes of Santa Cruz province, Argentina. [ABSTRACT FROM AUTHOR]

Genotype data from 14 microsatellite markers were used to assess the genetic diversity and differentiation of four guanaco populations from Argentine Patagonia. These animals were recently captured in the wild and maintained in semi-captivity for fibre production. Considerable genetic diversity in these populations was suggested by the finding of a total of 162 alleles, an average mean number of alleles per locus ranging from 6.50 to 8.19, and He values ranging from 0.66 to 0.74. Assessment of population differentiation showed moderate but significant values of FST = 0.071 ( P = 0.000) and RST = 0.083 ( P = 0.000). An amova test showed that the genetic variation among populations was 5.6% while within populations it was 94.4%. A number of 6.6 migrants per generation may support these results. Unambiguous individual assignment to original populations was obtained for the Pilcaniyeu, Las Heras and La Esperanza populations. The erroneous assignment of 18.75% Rio Mayo individuals to the Las Heras population can be explained by the low genetic differentiation found between these two populations. Thirty-nine of 56 loci per population combinations were in Hardy–Weinberg disequilibrium because of guanaco heterozygote deficiency, which may be explained by population subdivision. The high level of genetic diversity of the guanacos analysed here indicates that the Patagonian guanaco constitutes an important genetic resource for conservation or economic utilization programmes. [ABSTRACT FROM AUTHOR]

This assay was made in order to determine material and planting season more adequate for the definitive installation of poplar forest under environmental conditions of Mendoza, using the following clones: Populus euromaericana Conti 12 and Populus deltoides Harvard. Planting was made in two different seasons: autumn an spring, using as planting material: a. plant with roots and bud of 1 year old (R1T1); b. plants with roots of 1 year old and bud cut at 30 cm of soil level (R1T0); c. cuttings: 1.5-2.5 cm of diameter and 30-40 cm of length. Results were expressed in percentage of prendidas plants and wood percentage by hectare at seven years. The best result was for Conti 12 planted in autumn, using 1 year old plants, or planted in spring using R1T1 plants, R1T0 plants or cuttings. The best result for Harvard clone was planting in spring using R1T0 plants or cuttings. [ABSTRACT FROM AUTHOR]

Cardiac β-adrenergic receptors’ function was studied in the acute phase of Chagas’ disease in mice reinfected with Trypanosoma cruzi Tulahuen strain (Tul) and with parasites isolated from an infected patient (SGO-Z12). Genetic characterization of SGO-Z12 isolates demonstrated that it belongs to the zimodeme Z12, one of the prevalent ones in humans in Argentina. Electrocardiography, heart histopathology, parasitemias, and survival in infected and reinfected mice were also analyzed. Reinfected mice reached higher parasitemias, 14% of the infected with SGO-Z12 and 76% of the reinfected groups showed electrocardiographic abnormalities. Similar results were found in mice that were infected and reinfected with Tul. SGO-Z12-Reinfected and Tul-Infected groups exhibited cardiac β-adrenergic receptors’ affinity significantly diminished (p<0.001) and its density significantly increased (p<0.001) than in infected and non-infected groups. Histopathologic alterations in hearts from Tul and SGO-Z12-Reinfected mice were detected. Reinfections with T. cruzi, Tulahuen strain or SGO-Z12 isolate provoked cardiac dysfunctions of different degrees, from the acute phase on.Index Descriptors and Abbreviations: Reinfection; acute Chagas’ disease; Trypanosoma cruzi; cardiac damage, strain, isolate [Copyright &y& Elsevier]

This paper investigates the genetic diversity of one llama (Lama glama) and two guanaco (L. guanicoe) populations in Argentina by the analysis of six dinucleotide microsatellite loci markers derived from llama. Population parameters of the used markers such as allele size and distribution, mean heterozygosity, Hardy–Weinberg equilibrium, and population genetic distances were calculated, as well as polymorphic information content (PIC) and exclusion probability (EP). The camelid populations showed high mean heterozygosities and gene diversity values, with little differences between them, in concordance with the observed non-deviation from Hardy–Weinberg equilibrium. Among the total alleles, the analysis showed 25 (45%) private alleles in guanaco and 16 (36%) in llama. The results indicated that the investigated populations have high genetic variability and would be suitable as genetic stocks for conservation and sustainable utilisation programmes. [Copyright &y& Elsevier]

Abstract Shiga toxin-producing Escherichia coli (STEC) are important foodborne pathogens that can cause severe disease. The ability to adhere to epithelial cells is an important virulence trait and pathogenicity islands (PAIs) play an important role. Recently, researchers identified a member of the Heat-resistant agglutinin family and characterized this antigen named Hemagglutinin from Shiga toxin-producing E. coli (Hes). More importantly, they showed that hes and other genes such as iha , pagC and agn43 were integrated in each of the four modules present in the new PAI named Locus of Adhesion and Autoaggregation (LAA) whose presence is associated with severe disease linked to with LEE-negatives STEC. The distribution of LAA among STEC strains isolates from different origins between 2000 and 2015 from cattle, the farm environment, and food and harboring diverse virulence was investigated. The STEC strains were characterized by PCR to detect three modules of LAA and agn 43 (as marker of module IV), and phylogenetic groups were determined. LAA was found in 46% of LEE-negative STEC corresponding to serogroups O91, O174, O113, O171, O178, O130 and others. The presence of this PAI is associated with strains harboring stx2 (56%) and belonging to phylogroup B1 (91%). LAA is a novel pathogenicity island associated with strains isolated from Hemolytic Uremic Syndrome cases. Therefore, the results of this study contribute to a better understanding regarding the pathogenicity of this emergent subset of STEC strains harboring LAA as a predictor of virulence of LEE-negative STEC strains. Highlights • We investigated the distribution of a new Island named Locusof Adhesion and Autoaggregation among LEE-negative STEC strains. • A total of 354 LEE-negative STEC strains were selected fromcattle, the farm environment and food. • LAA was found in 46% of LEE-negative STEC corresponding toO91, O174, O113, O171, O178, O130, and others. • The presence of this PAI is associated with strains harboring stx2 (56%) and belonging tophylogroup B1 (91%). • Results contribute to understanding the pathogenicity of thissubset of STEC carrying LAA as a predictor of virulence of LEE-negative STEC. [ABSTRACT FROM AUTHOR]

Verotoxin-producing E. coli (VTEC) O157:H7 is the dominant serotype isolated from patients with HUS and, Argentina has the highest rate of HUS in the world. Molecular typing had allowed to identify subpopulations related to the origin and virulence of O157:H7 strains. Our aim was to perform a genetic characterization of 43 O157:H7 strains isolated in Argentine mostly from cattle and humans in order to establish the potential public health risk. For it, we used a combination of molecular subtyping methods in order to identify clade 8_ rhsA ( C3468G ), LSPA-6 and virulence profiles and, a cytotoxicity assay on Vero cell. All isolates carried the clade 8 SNP variant and 98% of them belonged to lineage I/II (2% lineage II). Isolates were grouped into eleven nle profiles, 46% were positive for all nle genes, while the remaining isolates, except two, showed incomplete OI-71, particularly lacked nleF . All isolates showed the plasmid profile ehxA-espP-katP-stcE and harbored ehaA , elfA , iha and l pfA variants lpfA1-3 and lpfA2-2 and, ECSP_0242. The frequencies of the remaining ECSP genes were 95% ECSP_2687, 88% ECSP_3286, 86% ECSP_3620, 53% ECSP_2870/2872 and 44% ECSP_1733. All O157:H7 strains, except the isolate identified as lineage II, were cytotoxic on Vero cells. Among Argentinean strains, most genetic markers occur at equal relative frequencies among clinical and bovine isolates, showing diversity mostly in nle genes profiles. The belonging of the isolates to hypervirulent clade 8 and lineage I/II, the high prevalence of nle and putative virulence factors genes, would allow assigning most O157:H7 strains of this region a high risk to public health. [ABSTRACT FROM AUTHOR]

We aimed to compare the genetic diversity existing in VTEC O157:H7 strains isolated from cases of human disease from Argentina and Chile. For it, 76 strains were studied in relation to the distribution of genes encoding virulence factors and subtyped by lineage-specific polymorphisms (LSPA-6), and phylogroups assignment. Our results show the almost exclusive circulation of VTEC O157:H7 isolates belonging to lineage I/II, associated with hypervirulent strains, and to the phylogroup E and, on the other hand, genetic diversity present among Argentinean and Chilean strains analyzed, mainly in relation to putative virulence determinants and nle profiles. [ABSTRACT FROM AUTHOR]

Verotoxin-producing Escherichia coli O157:H7 is the dominant serotype isolated from patients with hemolytic-uremic syndrome (HUS) and, Argentina has the highest rate of HUS in the world. However, not all O157:H7 isolates have the same ability to infect and cause disease in humans. It has been postulated that O157:H7 strains integrate subpopulations related to the origin and virulence. In order to study the population structure and genetic diversity of VTEC O157:H7 from Argentina, a combination of molecular subtyping methods such as multiple loci VNTR analysis (MLVA), single nucleotide polymorphisms (SNP) and phylogroups assignment were used. According to MLVA, high genetic diversity was found among strains isolated from cattle, humans and food. On the other hand, 92% of the isolates presented the allele tir 255 T > A T and 95% were assigned to phylogroup E. We did not find a significant association between the isolates origin and the allele T presence (P > 0,05) postulated as significantly overrepresented in human isolates. Our results show that human and cattle VTEC O157:H7 isolates from Argentina are a homogeneous group and, although it presents high genetic diversity in relation to their MLVA and virulence profiles, it is not possible to distinguish divergent populations. The presence in all the strains of a high number of T3SS effectors genes and the no association of genetic subtypes with strain source, is an alert about the potential risk in public health that VTEC O157:H7 cattle strains possess and, at less, a partial explication about the high incidence of HUS in Argentina. • A high genetic diversity using MLVA was observed among VTEC O157:H7 Argentinean strains. • Molecular subtyping studies did not allow to distinguish divergent populations. • Bovine strains appear to have the same genetic characteristics than human strains involved in serious diseases. [ABSTRACT FROM AUTHOR]