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Currently, teas and herbal infusions represent an important part of the human diet. Most contain phenolic compounds with high antioxidant activity, usually associated with human health protective functions. This attribute defines teas and infusions as nutraceutical foods. In Argentina, several native species are traditionally used for medical purposes. Some of those species are Larrea cuneifolia, Larrea nitida, Grindelia chiloensis, Pteromonnina dictyocarpa, Mandevilla laxa, and Monttea aphylla. The objectives of this study were to analyze the antioxidant power and the scavenging capacity of infusions obtained from those six medicinal plants, to characterize the phenolic profile, and to study in vitro their safety or cytotoxicity. Additionally, the potential use of two infusions as antioxidant additives in a food model was evaluated. The results indicated that the analyzed plant species are rich in phenolic acids (e.g., caffeic, ferulic, and chlorogenic acid), and flavonoids (e.g., quercetin and kaempferol), with high antioxidant power. The infusion blend obtained with G. chiloensis and L. cuneifolia exhibited the highest value of antioxidant capacity measured with the FRAP technique (193.4 μg EAA/mg DW). On the other hand, L. cuneifolia infusion showed the greatest antioxidant capacity determined by FRAP (131.9 ± 5.2 μg EAA/mg DW) and DPPH assays (0.453 mL/mg s). Additionally, L. cuneifolia infusion showed the highest phenolic content (232.8 μg GAE/mg DW) and flavonoid content (153.3 μg QE/mg DW). None of the infusions showed toxicity in mammalian cells, except for G. chiloensis. Furthermore, the L. cuneifolia and L. nitida infusions showed a high inhibitory effect on lipid oxidation in ground beef (55% and 51% at 4 days of storage, respectively). The results suggest that the studied infusions are safe and a rich source of antioxidants, which supports their use in traditional medicine. However, further exhaustive studies of G. chiloensis infusion are needed to ensure its safety, as it has shown cytotoxicity. Besides, it is worthwhile to advance the study of L. cuneifolia and L. nitida as sources of dietary antioxidants, due to their high antioxidant power and ability to protect against lipid peroxidation. [ABSTRACT FROM AUTHOR]

Arsenic (As) is a toxic metalloid present in high levels in diverse regions of Argentina. The aim of this study was to determine acute As-mediated toxicity in two different populations of autochthonous Hyalella curvispina amphipods from a reference site (LB) and an agricultural one (FO) within North Patagonia Argentina. Previously, both populations exhibited significant differences in pesticide susceptibility. Lab assays were performed to determine acute lethal concentrations, as well as some biochemical parameters. Lethal concentration (LC50) values obtained after 48 and 96 hr As exposure were not significantly different between these populations, although FO amphipods appeared slightly less susceptible. LC50-48 hr values were 3.33 and 3.92 mg/L As, while LC50-96 hr values were 1.76 and 2.14 mg/L As for LB and FO amphipods. The no observed effect concentration (NOEC) values were 0.5 mg/L As. Cholinesterase (ChE) activity was significantly diminished by As acute exposure (0.5–1.5 mg/L As), indicative of a significant neurotoxic action for this metalloid in both amphipod populations. Activities of catalase (CAT) and glutathione S-transferase (GST) and levels of reduced glutathione (GSH) were differentially altered following As exposure. CAT activity was increased after 96 hr As exposure. GST activity and GSH levels were significantly elevated followed by either a decrease or a return to control values after 96 hr treatment. However, additional studies are necessary to understand the mechanisms underlying the As-mediated oxidative effects in H. curvispina. Our findings suggest that measurement of ChE activity in H. curvispina amphipods might serve as a useful biomarker of As exposure and effect. [ABSTRACT FROM AUTHOR]

Background: The Pehuén or Monkey puzzle tree (Araucaria araucana) is an evergreen coniferous tree, which has been historically used for social, medicinal, and nutritional purposes. We have recently showed the value of A. araucana seeds as a rich source of micronutrients and antioxidants. This endemic species present in a reduced area in Argentina and Chile is endangered because of the low germination rate and the overexploitation of its edible seeds. Thus, the massive extraction of its seeds is ecologically non-viable resulting in limited availability of its active metabolites. However, biotechnological approaches are attractive strategies of production of valuable metabolites and healthy specimens of endangered plants. The aim of this work was to develop a protocol for in vitro production of antioxidants derived from A. araucana seeds and to obtain healthy plants by optimized seed germination. Results: Calli of Pehuén seeds were induced in Murashige and Skoog medium with different combinations of auxins and cytokinins, in light and dark conditions. Callus from embryonic axes developed in medium with 1 mg/l α-naphthaleneacetic acid and 1.5 mg/l 6-benzylaminopurine in light conditions had efficient biomass production, antioxidant activity, high phenolic, and flavonoid content and no cytotoxicity on mammalian cells. Additionally, 100 % germination was obtained in vitro and healthy plants were acclimatized to non-sterile conditions. Conclusion: In conclusion, in vitro culture of A. araucana could provide new and sustainable options for production of its valuable metabolites with possible therapeutic and nutritional uses. Also, optimized plant germination and acclimatization of endangered species can contribute to the preservation of pristine environments. [ABSTRACT FROM AUTHOR]

Background: The optimal management of recurrent anterior shoulder instability with significant glenoid bone loss in high-demand collision athletes remains a challenge. Purpose: To analyze the time to return to sport, clinical outcomes, and recurrences following a modified Latarjet procedure without capsulolabral repair in rugby players with recurrent anterior shoulder instability and significant glenoid bone loss. Study Design: Case series; Level of evidence, 4. Methods: Between June 2008 and June 2015, 50 competitive rugby players (practice >2 times per week and competition during weekends) with recurrent anterior shoulder instability underwent operation with the modified congruent arc Latarjet procedure without capsulolabral repair in our institution. Cases included 18 primary repairs and 32 revisions. Return to sports, range of motion (ROM), the Rowe score, a visual analog scale for pain in sport activity (VAS), and the Athletic Shoulder Outcome Scoring System (ASOSS) were used to assess functional outcomes. Recurrences were also evaluated. The postoperative bone block position and consolidation were assessed with computed tomography. The final analysis included 49 shoulders in 48 patients (31 revision cases). Results: The mean follow-up was 48 months (range, 24-108 months) and the mean age at the time of operation was 22.8 years (range, 17-35 years). Forty-five patients (93.7%) returned to playing rugby, all at their preinjury level of play. No significant difference in shoulder ROM was found between preoperative and postoperative results. The Rowe, VAS, and ASOSS scores showed statistically significant improvement after operation (P < .001). The Rowe score increased from a mean of 39.5 points preoperatively to 94 points postoperatively (P < .01). The VAS score decreased from 3.6 points preoperatively to 1.2 points postoperatively (P < .01). The ASOSS score improved significantly from a mean of 44 points preoperatively to 89.5 points postoperatively (P < .01). No recurrence of shoulder dislocation or subluxation was noted. The bone block healed in 43 shoulders (88%). Conclusion: In rugby players with recurrent anterior shoulder instability and significant glenoid bone loss, the modified Latarjet procedure without capsulolabral repair produced excellent functional outcomes, with most athletes returning to rugby at their preinjury level of play without recurrences. [ABSTRACT FROM AUTHOR]

Background: Early union and a rapid return to prior function are the priorities for young athletes with lateral clavicular fractures. Furthermore, it is essential to avoid nonunion in this subgroup of patients, as this is frequently associated with persistent pain, restriction of movement, and loss of strength and endurance of the shoulder. Purpose: To analyze the time to return to sport, functional outcomes, and complications in a group of athletes with displaced lateral clavicular fractures treated using closed reduction and minimally invasive double-button fixation. Study Design: Case series; Level of evidence, 4. Methods: A total of 21 athletes with displaced lateral clavicular fractures were treated with closed reduction and minimally invasive double-button fixation between March 2008 and October 2013. Patients completed a questionnaire focused on the time to return to sport and treatment course. Functional outcomes were assessed with the Constant score and the short version of the Disabilities of the Arm, Shoulder and Hand (QuickDASH) questionnaire. Pain was evaluated with the visual analog scale (VAS). Radiographs were reviewed to identify radiographic union, malunion, and nonunion. Results: Of the 21 study patients, 20 returned to sport after treatment; 100% returned to the same level. The mean time to return to play was 78 days (range, 41-120 days). Four patients (20%) returned to sport less than 6 weeks after surgery, 14 (70%) returned between 6 and 12 weeks after surgery, and 2 (10%) returned after 12 weeks. The mean Constant score was 89.1 ± 4.2 (range, 79-100), the mean QuickDASH score was 0.4 ± 2.6 (range, 0-7.1), and the mean VAS pain score was 0.4 ± 1.0 (range, 0-3) at final follow-up (mean, 41 months). The only complication was asymptomatic nonunion. Hardware removal was not necessary in any patient. Conclusion: Closed reduction and minimally invasive double-button fixation of displaced lateral clavicular fractures in athletes was successful in terms of returning to the previous level of athletic activity regardless of the type of sport, with excellent clinical results and a low rate of complications. [ABSTRACT FROM AUTHOR]

Background: Recent prospective randomized trials support primary plate fixation of displaced midshaft clavicle fractures. However, the safety and efficacy of this practice have not been well documented in athletes, nor has the time to return-to-sport. Purpose: To analyze the time to return-to-sport, functional outcomes, and complications in a group of athletes with displaced midshaft clavicle fractures treated using precontoured locking plates. Study Design: Case series; Level of evidence, 4. Methods: A total of 54 athletes with displaced midshaft clavicle fractures were treated with plate fixation between November 1, 2008, and December 31, 2012. The mean follow-up time was 22.4 months. Patients completed a questionnaire focused on the time to return-to-sport and treatment course. Functional outcomes were assessed with the Constant score and short version of the Disabilities of the Arm, Shoulder, and Hand (QuickDASH) questionnaire. Pain was evaluated with the visual analog scale (VAS). Radiographs were reviewed to identify radiographic union time, malunion, and nonunion. Results: Of the 54 patients, 53 returned to sports after open reduction and internal fixation of their fracture; 94% returned to the same level. The mean time to return-to-sport was 68 days (range, 5-180 days). Nine (16.6%) of the cases returned to sports before 6 weeks after surgery, 40 (74%) returned between 6 and 12 weeks, and 5 patients (9.2%) returned 12 weeks after surgery. The mean Constant score was 94.1 ± 5.2 (range, 78-100), and the mean QuickDASH score was 0.4 ± 4.7 (range, 0-7.1). The mean VAS pain score during follow-up was 0.29 ± 1.0 (range, 0-5). Three major complications occurred: 1 extrinsic compression of the subclavian vein, 1 nonunion, and 1 hardware loosening. Hardware removal was necessary in 5 patients (9.3%). Conclusion: Plate fixation of displaced clavicle fractures in athletes is a safe procedure resulting in excellent functional outcomes, with an early return to the same level of sports in the majority of patients. [ABSTRACT FROM AUTHOR]

In semi-arid regions, soil water and nitrogen (N) are generally limiting factors for corn ( Zea mays L.) production; hence, implementation of appropriate N fertilization strategies is needed. The use of precision agriculture practices based on specific site and crop properties may contribute to a better allocation of fertilizer among management zones (MZ). The aim of this study was to develop a model for diagnosis of N availability and recommendation of N fertilizer rates adjusted to MZ for dryland corn crops growing in Haplustolls. The model considered variability between MZ by including site-specific variables [soil available water content at sowing (SAW) and Available Nitrogen (soil available N-NO at planting + applied N, Nd)] using spatial statistical analysis. The study was conducted in Córdoba, Argentina in Haplustolls and consisted in four field trials of N fertilizer (range 0-161 kg N ha) in each MZ. The MZ were selected based on elevation maps analysis. Grain yields varied between MZ and increased with larger SAW and Nd at sowing. Grain responses to Nd and SAW in any MZ were not different between sites, allowing to fit a regional model whose parameters (Nd, Nd, SAW, SAW) contributed significantly ( p < 0.001) to yield prediction. Agronomical and economically optimum N rates varied among MZs. However, the spatial variability of optimum N rates among MZs within sites was not enough to recommend variable N fertilizer rates instead of a uniform rate. Variable N fertilizer rates should be recommended only if variability in SAW and soil N among MZ is greater than that found in this work. [ABSTRACT FROM AUTHOR]

Abstract: Mud walls are frequent in many archaeological sites, including sites located in semi-desert regions. In cases with buried walls, the geophysical methods can be useful tools for their investigation, since they provide maps of the subsoil in a non-invasive way and in relatively short times. This article deals with the characterization of mud walls in very dry soils through the resistivity method, discussing a methodology to satisfactorily apply the method in this kind of adverse environment and how to interpret the results. The case of the Palo Blanco archaeological site, a pre-Incaic village located in the NW region of Argentina, is analyzed. In very dry soils, it is frequent that the electrical current cannot be injected due to the high values of electrical resistivity at the shallowest portions of soil, which makes the resistivity method useless. Here we show how this problem can be systematically overcome by wetting a shallow thread between each pair of injection electrodes, and the manner in which the resulting profiles can be analyzed. We perform numerical simulations of the resistivity profiles considering 3D models of mud walls and wetted threads that reproduce experimental situations, and compare them to 2D field data. The resistivity profiles are analyzed for different orientations and distances between the wall and profile, and fluctuations of the soil parameters. The experimental profiles are interpreted from these simulations and compared to ground penetrating radar (GPR) profiles. The resistivity methodology shows effective for characterizing the size and depth of the mud walls, even in cases with collapsed or much eroded walls, for which GPR often fails. [Copyright &y& Elsevier]

Abstract: We present results from a geophysical prospection at a historical Jesuit Mission, located in San Ignacio (Misiones-Argentina), declared World Monument some years ago. We studied different sectors looking for buried structures; the total area under study covered 36 ha. In this work we will show the results obtained in a sector that at the time of the prospection was at imminent risk of being damaged by a wrong management of the historical resource. To optimize the data acquisition and the preliminary in-situ analysis of the results, we performed an electromagnetic survey using a multifrequency electromagnetic induction device (GEM-2) to have a first insight of the near surface electrical distribution. From 2D and 3D visualization of data, different targets were identified as possible historical structures. Around these anomalous zones, we performed different dipole–dipole profiles, forming high resolution grids for later 3D inversions. Further inversions of the electric and electromagnetic data completed the characterization of the anomalies. One of the main results of this work is that the 3D electric image obtained from 1D inversion of electromagnetic data coincides with the 3D images obtained from resistivity inversion, but at a much less time consuming cost. [Copyright &y& Elsevier]

Abstract: Wheat fields in the semiarid region of Argentina are spatially variable in soil nitrogen (N) fertility and crop productivity. By accounting for spatial variation in soil N levels, variable-rate fertilizer application may improve crop yield, protein content, and N use efficiency within fields. Therefore, there is interest in applying variable rates of N fertilizer across the landscape. The general objectives of this research are to determine relationships among yield, protein and N rates, using spatial regression analysis of yield monitor data; and to optimize variable-rate application (VRA) of nitrogen fertilizer for wheat. The data were drawn from an on-farm N trial of 10.2ha within a 44ha field conducted in Manfredi, Córdoba, Argentina, in 2003. The experimental design was a complete block strip trial that included two different types of soils in terms of landscape (Hilltop and Lowland) and two different antecessor crops (Corn and Soybeans). The fertilized strips were wider than the combine platform width, with zero N application as the control, and five other rates of elemental N (12, 37, 62, 88 and 112kgha−1). Yield data were obtained with a combine grain monitor, and grain samples for quality analysis were manually collected from the grain flow of a combine harvester, analyzed for quality in the laboratory and converted into a geographical information system (GIS) layer, together with the yield monitor data. Yield and grain quality variability was observed across the field, and among treatments. The combination of yield maps, soil moisture and protein content can help to determine management zones in order to maximize economic benefit. This approach offers opportunities to optimize grain protein on a site-specific basis by accounting for spatial variability of N fertility within individual fields. [Copyright &y& Elsevier]

Abstract: Argentina is a country with both rich floral biodiversity and cultural diversity. Traditional herbal medicines are important in the health care of most people, and rely heavily on the use of indigenous plants. An ethnobotanical survey of the “Sierra de Comechingones” made over a 26-year period (1979–2005), indicated that 65 families and 149 different genuses were used in traditional medicines. The use of these medicines was observed to be widespread and prevalent over orthodox medicine. Medicinal native plants from this mountain range make up 31% of the total Argentina medicinal native flora. In addition, there are 15 endemic species that grow only in the region. The botanical name, popular uses, parts utilized, as well as the distribution of these medicinal plants from the “Sierra de Comechingones”, Argentina, were summarized. Previous reports on phytochemical and biological activities in relation to cancer, antimicrobials and pesticides were also included. [Copyright &y& Elsevier]

Appropriate strategies for nitrogen fertilization in corn production is specially important in semi-arid regions, where soil water and nutrients are limiting factors. Precision agriculture has the potential to adjust fertilizer rates according to soil types and/or other defined conditions within management zones. The objectives were: i) to determine the site-specific response of corn to nitrogen and available water at planting, and ii) to determine the economic and agronomic optimal levels of nitrogen and water. Three management zones with different production potential were identified: rainfed high and low potential and high potential with irrigation. The data are from on-farm trials for the 2004-2005 crop season, in Manfredi (Córdoba) with a uniform N rate along strips (0, 32, 64, 96, 129 and 161 kg N ha-1 in the dry land and 0, 64, 137, 212, 279 and 351 kg N ha-1 in the irrigated area) and a randomized complete block design to estimate site-specific crop response functions. Spatial autocorrelation is taken into account in regression estimation of N response functions by landscape position, in the form a spatial autoregressive error structure. Results suggest that N response differs significantly by landscape position and by soil water availability. Yields ranged from 4,914 to 11,346 kg ha-1 in the zone of low productivity, between 4,956 and 12.204 kg ha-1 in the one of high productivity and between 7,830 and 14,387 kg ha-1 in irrigated plots. The agronomical (DOA) and economically (DOE) optimal N rates also differed among management zones, being DOA = 285. 184 and 162 kg ha-1 for the zones from greater to smaller productivity, meanwhile DOE values were 171, 111 and 90 kg ha-1, respectively. Initial soil nitrogen and available water inclusion allowed us to build a single N response model for the rainfed management zones. Besides, irrigated experiment maize performance was well predicted by the same model type but excluding available water (non-limiting factor), as input. The model performed well using either available N at 60 or 200 cm soil depth, and available water al 200 cm depth. This model allowed us to recommend fertilization rates using variable rate application, maximizing net return to N, and minimizing environment contamination risks, by over dose input (i.e. N fertilization) application. Our conclusions are preliminary because they come from a single year experiment, which did not include the whole range of expectated initial conditions. More scenarios are needed in order to validate the proposed model. [ABSTRACT FROM AUTHOR]

Abstract: Here, we developed a quantitative risk assessment for thermophilic Campylobacter spp. related to the consumption of salad prepared alongside broiler meat. The assessment considered initial contamination levels, cross-contamination and decontamination events during the broiler slaughter process and distribution, and storage and consumption patterns in Argentina and other Latin American countries. The model predicted an infection risk of 3.32×10−4 per serving. This estimation was variable according to the dose–response model used. Considering the number of chickens slaughtered annually in Argentina, the estimated number of people who could suffer campylobacteriosis related to poultry meat consumption was, on average, 484,304. The risk of human campylobacteriosis was most sensitive to the probability of infection from a Campylobacter (r =0.72), the number of Campylobacter spp. per serving (r =0.40), the frequency of washing the cutting board (r =−0.31), the preparation of raw poultry before salad using the same cutting board (r =0.14), and the frequency of hand washing (r =−0.14). The most sensitive stages of the process identified through the risk assessment can be used as a basis for measures of risk management. Public campaigns on hygiene habits during food preparation at home should focus on the importance of washing the cutting board before preparing raw and ready-to-eat foods and of washing the hands during food preparation. [Copyright &y& Elsevier]

The interpretation of the meanings of constructed space plays an important role in understanding how a certain society might have been structured in the past. This paper presents the colony of Floridablanca (Patagonia, 18th century) and examines how the different discourse levels are articulated in the construction of the colony's spaces according to the ideal model of a social order based on the principles of the Spanish Enlightenment. The focus is on the convergence and divergence between the material world and the narratives referring to such spaces created during the existence of the colony. This approach, developed by an interdisciplinary team, involved the inclusion and interpretation of historical, archaeological, and geophysical data. Studied along three lines of evidence, the narrative analyses and material construction show how the discourse on the social organization of Floridablanca articulates convergence and divergence from these planes in different ways for different sectors of the colony. [ABSTRACT FROM AUTHOR]

• The Pehuén (Araucaria araucana) is a prehistoric tree adapted to hostile environments. • 97% of antioxidant power in piñón were in its coat, which is discarded as waste. • Piñón coat extract increases antioxidant defenses of cyclophosphamide treated rats. • Piñón extract inhibits more than 60% of the acid corrosion of steel. • The valorization of piñón waste expands possible applications in industrial fields. In the last decade, green chemistry has been attracting great interest in many contexts, including, among others, natural antioxidants. However, only a few works deal with natural residue extracts and biowaste, which could be an efficient, economical and environmentally friendly source for the production of useful compounds. In this study, we look for antioxidant activity in Araucaria araucana seeds, an iconic pine species of the Argentine and Chilean Patagonia commonly known as "pehuén". Piñones are the edible pehuén seeds, and it is estimated that approximately 40 tons of piñones are harvested annually in Argentina and Chile. The chemical composition, antioxidants, metal corrosion-inhibiting properties and biological activity of edible and discarded piñón tissues were determined. Acute toxicity was discarded by in vitro testing and double fluorescent staining. Biological activity was evaluated in vivo by determining redox markers in salivary glands from rats treated with Cyclophosphamide (an oncological drug). All piñón tissues had antioxidants and antioxidant activity, with the coats showing the highest levels (up to 404 µg ascorbic acid equivalent per mg). The coats, in particular, had high gallic acid, catechin, quercetin and tannin contents, and more antioxidant activity, polyphenols and flavonoids than berries from the region. Results by X-ray fluorescence spectrometry showed that Na, Mg, P, S, Cl, K, and Ca were majority elements in the coat, embryo and endosperm. Furthermore, coat extract also showed significant anti-corrosion activity and in vivo protection against oxidative damage. The results indicate that piñón biowaste is a low-cost attractive source of natural antioxidants with potential nutraceutical, medical and metal corrosion protection applications. [ABSTRACT FROM AUTHOR]