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The influence of the geographical location and clone type on the contents of flavonols and organic acids of Sauvignon blanc grapes over the ripening process was investigated. The assay was carried out on three commercial clones of cv. Sauvignon blanc (Clone 242, Clone 107, and Clone 1-Davis) grown in two zones (referred to as low and high zones) in Casablanca Valley, Chile. The low zone is closer to the Pacific Ocean (i.e., 20 km away) than the high zone (which is 37 km away). Clear differences in the contents of total phenols, flavonols and organic acids of the grapes were observed during ripening. All the clones grown in the low zone exhibited a higher titratable acidity than those grown in the high zone. An analysis of the flavonol contents of the grape skins showed differences among clones associated with the geographical zone of cultivation. There was no difference in the tartaric acid concentration among clone types; however, a higher tartaric acid concentration was found in clones grown in the low zone than those grown in the high zone for all clone types. Similar results were found for the malic acid concentration. A discriminant analysis showed that the chemical analysis for the contents of total phenols, flavonols and organic acids influenced the classification based on the clone type. The results showed that grapes of different qualities can be grown in two geographical subunits into the larger area of Casablanca Valley. [ABSTRACT FROM AUTHOR]

Avocados (Persea americana Mill.) are one of the crops with the highest water footprints in Chile and the production is at risk due to severe and frequent droughts. The current production is mostly based on sexually (seed) propagated rootstocks, while clonally propagated rootstocks are on the rise. In a recent study, we found differences in aerial, root growth and water use efficiency between trees grown on these two different rootstocks under controlled continuous fertigation and environmental conditions. In this study, we further describe possible mechanisms which drive the differences. Avocado cv. "Hass" grafted on "Dusa" (D, clonally propagated) and "Mexicola" (M, sexually propagated) rootstocks and different root segments (3, 5 and 8 cm from root tip) were investigated using a combination of hydraulic measurements and polar metabolite (GC-MS) techniques. The results show significant differences in root hydraulic properties, indicating that "Mexicola" fine roots have higher water uptake capacity. The polar metabolites analysis revealed 13 compounds significantly different between rootstocks while nine were found significantly different among root segments. Principal component analysis (PCA) revealed differences between rootstocks and root segments. The data presented here highlight the importance of considering key physiological knowledge in avocado rootstocks breeding programs to be better prepared for future challenging environmental conditions. [ABSTRACT FROM AUTHOR]

The purpose of this study is to explain the financial performance of companies in Latin America through the lens of capital structure and ownership structure. We perform a quantitative analysis of companies in Brazil, Chile, Mexico, and Peru using a panel data method. To avoid endogeneity problems, instrumental variables, generalised method of moments models, and panels with random effects are employed. The data cover the period 2000 to 2015. We find a positive relationship between financial performance, growth, and size of the company. However, there are mixed results for short- and long-term financial leverage, as well as for company liquidity. With respect to the ownership structure of Chilean companies, a positive effect is observed for the first major shareholder with financial performance. In general, our results are in line with those of previous studies. However, the existence of mixed results between companies and countries makes for an interesting and novel conclusion. [ABSTRACT FROM AUTHOR]

In Mediterranean climates, many deciduous fruit trees are unable to meet their seasonal chill requirements, a situation that may be exacerbated by global warming. Modeling approaches can be used to assess the impacts of climate change on tree crops for the past and forecast possible impacts for the future. We apply modeling approaches to assess climate change impacts on Chilean fruit production in nine major agricultural sites. Using a weather generator, we obtained 100 years of plausible weather data for scenarios produced by 15 climate models for two Representative Concentration Pathways (RCPs). Winter chill, safe winter chill (both quantified in Chill Portions - CP), and the percentage of years with spring frost were estimated for two reference years, 2050 and 2085. Projections show a considerable chill reduction in northern regions in all future scenarios. Relatively stable conditions are projected for southern regions, whereas most of the central sites are expected to lose between 10 and 15 CP by 2050. For 2085, expected chill reduction is much more severe. The percentage of years with spring frost is projected to decrease in all locations, varying according to RCP scenario and year. Results highlight that in northern sites, some species may fail to meet their chill requirements in the future. In other regions, strategies to mitigate the effects of chill shortfalls may become critical to ensure adequate yields. Results may be useful for geneticists, breeders, physiologists, dormancy researchers, and growers making production decisions, e.g., on selection of appropriate species and varieties. [ABSTRACT FROM AUTHOR]

Pregnancy complications and obstetric outcomes were compared in 80 Chilean (PPCOSCh) and 70 Argentinian (PPCOSAr) pregnant women. Reference groups of Chilean and Argentinian normal pregnant women from the same antenatal care units were also compared. PPCOSCh showed a higher prevalence of gestational diabetes mellitus (GDM) (OR, 2.28, 95% CI: 1.08-4.77, p = .030) and a lower prevalence of pregnancy-induced hypertension (PIH) (OR, 0.20, 95% CI: 0.07-0.54, p = .001) compared to PPCOSAr. In the normal pregnant groups, the prevalence of PIH was lower in Chilean women compared to Argentinian women (OR, 0.24, 95% CI: 0.10-0.62, p = .001). Similar to the pattern observed in the normal populations, newborns from PPCOSCh had higher birth weight and length compared with the newborns of PPCOSAr (p = .006 and .014, respectively). In conclusion, differences in pregnancy complications and obstetric outcomes between Chilean and Argentinian pregnant women with PCOS could be determined by ethnic diversity together with environmental factors of both populations. Impact Statement What is already known on this subject: The reproductive and metabolic phenotypes of women with polycystic ovary syndrome vary between different populations, which could significantly influence the obstetric and neonatal outcomes in this syndrome. What the results of this study add: Pregnant women with PCOS from two Latin American countries (Chile and Argentina) exhibit differences in the prevalence of gestational diabetes and pregnancy-induced hypertension, and in the birth weight of their newborns. What the implications are of these findings for clinical practice and/or further research: Ethnic diversity together with environmental factors are fundamental elements that must be considered in the management of pregnant women with PCOS. [ABSTRACT FROM AUTHOR]

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• Continuous fertigation and environmental conditions resulted in higher growth rates. • Aerial and root growth of plants grown on Mexicola (S) and Dusa® (C) rootstocks differed. • Higher canopy area, trunk diameter, height and root carbohydrates in S than C. • Positive impact on water and nutrient use efficiency of this alternative system. • A novel method for automated rhizotron photo analysis and root differentiation. Avocado production is nowadays questioned worldwide and at risk due to climate change and the high water footprint of this crop. Thus, there is need for the development or adoption of new strategies such as alternative production systems. In this study, Hass avocado plants grafted on two rootstocks (Mexicola -seed propagated and Dusa® - vegetative-propagated and referred as clonal) were grown in a greenhouse and substrate (coir growth container, 55 L of volume and 500 × 480 mm, H X W) culture system in Valparaiso Region, Chile. Plant growth and development during the vegetative and reproductive phases until end of flowering (63 weeks) were monitored. Plant aerial and root parameters from these two rootstock types (seed and clonal) were monitored by measuring canopy and trunk area, trunk height, root area, type of roots (rhizotron), non-structural carbohydrates dynamics, further primary metabolites, water use efficiency (WUE) and nitrate and phosphate use efficiency (NUE and PUE). Results of this study corroborated that continuous fertigation with nutrient solution provide better growing conditions resulting in prolonged and more continuous growth and flowering than open field conditions. In addition, differences in aerial and root growth between plants grown on these two different rootstocks under similar fertigation and environmental conditions were found. Plants grown on Mexicola rootstock were more efficient energetically as sustained by higher trunk area, tree height and higher root content of the main non-structural carbohydrates (mannoheptulose and perseitol) than plants grown on the clonal rootstock. Our findings suggest that this alternative growing system for Hass avocado, besides being more intensive could have a positive impact on environmental indicators (WUE, NUE and PUE) related to sustainability. [ABSTRACT FROM AUTHOR]

Available options for mitigating the impacts of extreme weather events on temperate fruit trees involve a number of risks and uncertainties, leaving growers hesitant about the benefits of implementing new technologies to protect their orchards. We used Decision Analysis approaches, which account for these risks and uncertainties, to assess investment decisions in sweet cherry production systems in central Chile. We evaluated the adoption of polyethylene covers for orchards in northern- and southern-central Chile. Gathering expert and key stakeholder knowledge, we identified relevant variables for the adoption decision and developed a causal impact pathway model. We parameterized this model by collecting estimates from experts in the form of probability distributions. We implemented the model as a Monte Carlo simulation and projected probability distributions for the Net Present Value and the annual cash flow. Results highlight that farmers in southern-central Chile could expect major benefits from covering their orchards, with a 90% confidence interval for the Net Present Value from −33,605 USD to 595,447 USD. In northern-central areas, implementing covers did not significantly improve the Net Present Value (90% confidence interval from −149,597 USD to 433,361 USD). Across zones, our model results were sensitive to market price, crop yield, and fruit quality problems (i.e. low firmness). Cover effectiveness against rain events was relevant only in the southern-central zone, whereas effectiveness against frost events was relevant in both sites. Expected Value of Perfect Information calculations revealed that additional information on yield and market price could substantially help to make a confident decision. Our simulations suggest that orchard protection in southern-central Chile may be necessary for secure and profitable cherry production in the future. In this case study, we demonstrated the applicability of Decision Analysis to support farmers in identifying appropriate and effective strategies in time to overcome future challenges resulting from climate change. Unlabelled Image • Sweet cherry farmers seek options such as covering orchards to meet challenges related to climate change. • Decision Analysis approaches allow assessing these options for complex scenarios. • We unpack sweet cherry system complexity and include current knowledge into decision forecasts. • Covers may offer major benefits in southern-central but not northern-central Chile. • Key variables for this decision are market price, yield and problems related to low fruit firmness. [ABSTRACT FROM AUTHOR]

Cortical lacunae caused by drought, especially observed in hybrids originating from Vitis rupestris, disrupt the connection between roots and soil. Yet, the physiological processes behind lacuna formation during drought and its consistency across Vitis species remain unclear. Here, we used a root pressure probe to investigate fine root hydraulic and mechanical properties, in the arid-adapted R-65 and drought-susceptible 101-14Mgt cultivars. We then performed P-V curves, root sap osmolality, and electrolyte leakage (EL) and used fluorescent light microscopy techniques. Only 101-14Mgt showed lacunae formation during drought due to its stiffer cortical tissue, unlike R-65. Lacunae resulted in a notable decline in root hydraulic conductivity during severe drought, with increased EL and root sap osmolality, indicating potential cellular damage. R-65 displayed different and xerophyte-like characteristics featuring a higher turgor loss point and decreased root capacitance, essential for maintaining root structural integrity in arid conditions. Our findings highlight lacuna formation is impacted by root tissue elasticity possibly linked to specific Vitis species favoring deeper rooting. In arid-adapted grapevines, hydraulic regulators such as reduced turgor loss point, and root capacitance could contribute to enhanced drought tolerance., (© 2024 John Wiley & Sons Ltd.)

Clonal rootstocks are one alternative used by the walnut industry to control damage caused by Phytophthora species, traditionally using plants grafted on susceptible Juglans regia rootstock. Vlach, VX211, and RX1 are clonal rootstocks with a degree of resistance to Phytophthora species. The resistance to pathogens in these rootstocks depends on the resistance mechanisms activated by the presence of the pathogen and subsequent development of responses in the host. In this work, we analyzed how plants of J. regia , Vlach, VX211, and RX1 responded to inoculation with Phytophthora cinnamomi or Phytophthora citrophthora isolates obtained from diseased English walnut plants from Chilean orchards. After inoculation, plants of Vlach, VX211, and RX1 showed canopy and root damage indexes that did not differ from noninoculated control plants. In contrast, plants of J. regia , which is susceptible to P. cinnamomi and P. citrophthora , died after inoculation. Vlach, VX211, and RX1 plants inoculated with P. cinnamomi or P. citrophthora showed greater root weight and volume and greater root growth rates than their respective controls. These results suggest that short-term carbohydrate dynamics may be related to the defense mechanisms of plants; they are immediately activated after inoculation through the production of phenolic compounds, which support the further growth and development of roots in walnut clonal rootstocks. To our knowledge, this is the first study that comprehensively characterizes vegetative and radicular growth and the dynamics of sugars and phenols in response to infection with P. cinnamomi or P. citrophthora in walnut rootstocks.

Background: Sleeve gastrectomy (SG) is an established bariatric procedure which produces substantial and rapid weight loss and hence can lead to an increase in gallstones development., Objectives: To demonstrate the early and late appearance of gallstones after SG., Materials and Methods: A prospective protocol was established in consecutive patients submitted to SG. Clinical and ultrasound evaluations were performed early (1 to 2 y) and late after surgery (over 6 y)., Results: From 109 patients included, 13 (13.1%) had a previous and 10 (10.1%) had simultaneous cholecystectomy at the time of SG. Therefore, 86 patients were submitted to surveillance. Seven patients were unreachable, leaving 79 patients for late follow-up. Forty-five patients (57%) had alithiasic gallbladder late after surgery, whereas 34 patients (43%) showed appearance of gallstone. From them, 53% developed gallstones late after surgery (mean, 7.5 y). Among the group with early development of stones, 69% were symptomatic and in the latter group only 17%., Conclusions: Study with 92% of follow-up late after SG demonstrated a 43% development of gallstones: half earlier and half late after surgery. We emphasize the need for late control to detect the real appearance of gallstones after SG.

Background: Studies performed in Anglo-Saxon countries show that 5% of patients are resistant to the antiplatelet effects of aspirin., Aim: To assess the prevalence of aspirin resistance in a sample of Chilean cardiovascular patients and its association with clinical and laboratory characteristics., Patients and Methods: Ninety nine patients (30 women, 63+/-10 years) treated for stable cardiovascular diseases with aspirin 100-325 mg/day were studied. Clinical and basic coagulation variables were assessed. Platelet aggregation was studied with platelet rich plasma using three different agonists in an optical aggregometer. Aspirin resistance was defined as an aggregation 20% with arachidonic acid and an aggregation 70% with ADP or collagen., Results: Eleven patients (11.11%, 95% CI= 4.95-17.27%) complied with both criteria and were classified as aspirin resistant. Current smoking was more common in aspirin resistant patients (63.6 vs 29.6%, p=0.039)., Conclusions: Aspirin resistance was found in a significant proportion of cardiovascular patients and was more common among current smokers.