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Anthropogenic disturbance often results in the proliferation of native species of particular groups that leads to biotic homogenization. Leaf-cutting ants are an example of such winner organisms in tropical rain forests, but their response to disturbance in dry forests is poorly known. We investigated Atta colony density in areas of tropical dry forest in Brazil with different distance to roads and vegetation cover. Atta colonies were surveyed in 59 belt transects of 300 × 20 m, covering a total area of 35.4 ha. We found 224 Atta colonies, 131 of which were active and belonged to Atta opaciceps (87 colonies, 2.45 ha−1), A. sexdens (35 colonies, 0.98 ha−1) and A. laevigata (9 colonies, 0.25 ha−1). The density of active colonies sharply decreased from 15 ± 2.92 ha−1 in the 50-m zone along roads to only 2.55 ± 1.65 ha−1 at distances up to 300 m. The reverse pattern was observed for inactive colonies. Active Atta colonies preferentially occur in areas with low vegetation cover, while inactive colonies prefer areas with high vegetation cover. We demonstrate for the first time that anthropogenic disturbances promote the proliferation of leaf-cutting ants in dry forest in Brazil, which may affect plant regeneration via herbivory and ecosystem engineering as demonstrated for rain forests. [ABSTRACT FROM PUBLISHER]

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The relationship between hypophosphatemia (HP) and malnutrition in older hospitalized patients has received little attention. We sought to investigate this association among this population. The study participants were consecutively admitted to a geriatric acute care ward in six hospitals. Malnutrition screening was conducted by Mini Nutritional Assessment-Short Form. Patients were divided into two groups according to serum phosphate: HP (<0.68 mmol/l) and non-HP groups (>0.68 mmol/l). Of 335 participants, 7% of subjects had HP. Malnutrition or nutritional risk was present in 86 and 56% of participants with and without HP, respectively (P = 0.003). The analysis indicated 9.8, 86.4, 97.9 and 44.0% sensitivity, positive predictive value, specificity and negative predictive value of HP with regard to malnutrition, respectively. This study demonstrated that HP in older hospitalized patients is associated with malnutrition and may be used as an indicator of nutritional risk. Contrary, normal serum phosphate does not exclude being at nutritional risk. [ABSTRACT FROM AUTHOR]

• The woody flora of the Caatinga dry forest is able to resprout following consecutive coppicing. • Resprouts are produced in abundance regardless of the species and the resprout type coppiced. • Resprouting capacity is directly related to the diameter of the coppiced stem. • Chronic human disturbances and harsher abiotic conditions mediate responses to coppicing and the performance of new shoots. Resprouting is a widespread mechanism through which woody plants recover from biomass loss and/or abiotic stress, particularly in fire-prone ecosystems. Here, we assess the resprouting responses to coppicing exhibited by woody plant species in a human-modified landscape of Caatinga dry forest, in the northeast of Brazil. A total of 150 resprouts from 19 species (trees and shrubs) were experimentally coppiced. Shoot performance (number of new shoots, length, diameter and coppicing capacity) and mortality were monitored through a 15-mo period. Resprout diameter, chronic disturbance and environmental factors (rainfall, soil fertility and light availability) were assessed as explanatory variables. Of the144 coppiced resprouts, 72.2 % produced new shoots, with a total of 217 new shoots across the 19 focal species and emerged vigorously across all resprout types (root, root collar and stem). Shoot density reached 1.5 ± 1.2 shoots per resprout, with a length of 11.33 ± 10.1 cm and a diameter of 0.2 ± 0.1 cm. When pooling all new shoots across species, resprout diameter was found to have a positive effect on shoot number, length, diameter and coppicing capacity. At species level, resprout diameter was also the most important predictor. However, chronic disturbance had both negative and positive effects on some performance indicators of some species, as did rainfall, soil fertility and leaf area index. Finally, mortality rate was not affected by any of the explanatory variables assessed, neither at species nor community level. Our findings suggest that in human-modified landscapes of Caatinga dry forest, woody flora probably contain a large number of resprouting species (dominant species, in some cases), which are able to vigorously produce new shoots in response to biomass loss. Furthermore, we found shoot performance to be mediated by variables that affect plant growth. Although the Caatinga dry forest flora did not evolve in the presence of fire, resprouting is expected to play a key role in its regeneration and dynamics. [ABSTRACT FROM AUTHOR]

Summary Background Weight loss and low body-mass-index (BMI) are well-known risk factors for mortality among older persons. Both items represent a reduced nutritional state but their nature is different. It is, however, unclear which of these factors is more important for prognosis and if there is interference or interaction between them. Objective To measure the prevalence of low BMI and weight loss in nursing home residents and to analyze their impact on mortality. Methods The nutritionDay in nursing homes is an international annual one-day cross sectional survey evaluating malnutrition and 6-months mortality. The data collected from 2007 to 2012 were analyzed. The mortality risk due to a BMI <20 kg/m 2 and weight loss >5 kg was calculated by logistic regression analysis with adjustment for confounding factors. Results In total, 10,298 residents with a mean age of 85 years (78% female) from 191 nursing homes in 13 countries were included in the analysis. Eighteen percent (17.7%) had a low BMI < 20 kg/m 2 , and 11.3% lost > 5 kg of body weight in the previous year. Low BMI <20 kg/m 2 and weight loss >5 kg were both independent and significant risk factors for 6-months mortality (OR 1.7 and 1.5; p < 0.001 in the adjusted model). In comparison to the effect size of low BMI and weight loss alone, the interaction of both factors was substantial (OR = 1.4; p = 0.056). The average 6-months mortality was 13.8%. Subjects with BMI ≥20 kg/m 2 without weight loss >5 kg presented the lowest mortality of 11.2%. In subjects with one of the two features, weight loss >5 kg or low BMI <20 kg/m 2 , mortality was significantly increased to 17.4% and 19.8%, respectively. However, if both features were present simultaneously the mortality increased disproportionally to 35.7% (OR 3.5; p < 0.001). In addition, this study presents an overlap and a strong dose-effect relationship of both items with regard to the 6-month mortality. Conclusion A BMI <20 kg/m 2 and weight loss >5 kg in one year are both independent and equally relevant risk factors for the 6-months mortality of nursing home residents aged 65 years or older. For this reason weight loss should be avoided and residents with a low BMI and weight loss should receive particular attention and nutritional care. [ABSTRACT FROM AUTHOR]

[Display omitted] • Caatinga soil seed banks have low species richness, density, and persistence. • The proportion of viable seeds is similar in goat-exclosure and free-access plots. • Taxonomic and functional seed composition remains unchanged after goat exclosure. • Goat exclosure increases seedling survival in seedling transplantation experiments. • Free-ranging goats have the potential to impair forest regeneration and resilience. Livestock browsing and trampling can deplete plant regeneration and thus drive natural ecosystems towards degradation. This phenomenon may be particularly true in tropical dry forests, which support extensive livestock herds feeding on native vegetation, but has rarely been experimentally addressed. Here we examine how browsing and trampling by exotic goats impacts seed bank and seedling survivorship of woody plant species in a Caatinga dry forest by performing a 4-year exclosure experiment. Soil seed bank and transplanted seedlings from four woody plants species were monitored through a year across 14 and 10 paired plots (free goat-access vs exclosure plots), respectively. Regardless of treatment, the soil seed bank was low in density 14 seeds/m2 (±13, standard deviation) and taxonomically impoverished (24 species). Small to intermediate-sized seeds from dry fruits (75%) and abiotically dispersed species (65%) prevailed. The most common attractive structure was an elaiosome (33%), but pulp (14%) and aril (9.5%) were also recorded. 60% of the species presented some type of dormancy and 32% presented a pleurogram. 57% of the seeds were classified as forming a transient seed bank, while seasonally transient seeds accounted for 43% of the total seed bank. Seed bank attributes were not affected by goats, including proportion of viable seeds (25.85 ± 41.3 in exclosure plots vs 31.45 ± 42.49 in free-access plots) and diversity. However, seedling survival one year after transplantation was higher for the plant species in the exclosure plots (68.4%) as compared to the free-access plots (39%). Although there were no significant differences in seed bank, our results suggest that free-ranging goats in densities typical of the Caatinga region can impose elevated seedling mortality to the dominant woody dry forest species even considering a short period of time. [ABSTRACT FROM AUTHOR]

Copyright of Zeitschrift für Gerontologie und Geriatrie is the property of Springer Nature 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.)