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Seventy-three percent of aerial insectivore species of birds breeding in North America have declined in the past five years. This decline is even greater in migratory insectivorous species, which face stressors in both their breeding and non-breeding ranges. The Purple Martin (Progne subis) is an aerial insectivore swallow that overwinters in South America and migrates to North America to breed. Purple Martin populations have declined by an estimated 25% since 1966. The eastern subspecies (P. subis subis) has declined the most and overwinters in the Amazon Basin, a region rich in environmental mercury (Hg) contamination. Previous studies reported elevated levels of Hg in feathers of this subspecies, which correlated negatively with body mass and fat reserves. Given the propensity of Hg to disrupt the endocrine system, and the role of thyroid hormones in regulating fat metabolism, this study quantifies concentrations of Hg and the thyroid hormone triiodothyronine (T 3 ) in the feathers of P. subis subis. To our knowledge, this is the first study to extract and quantify T 3 in feathers; thus, we developed, tested, and optimized a method for extracting T 3 from feather tissue and validated an enzyme immunoassay (EIA) to quantify T 3 in Purple Martin feathers. The developed method yielded acceptable results for both parallelism and accuracy. The observed T 3 concentrations were statistically modeled along with total Hg (THg) concentrations, but these variables were not significantly correlated. This suggests that the observed variation in THg concentration may be insufficient to cause a discernible change in T 3 concentration. Furthermore, the observed effect of breeding location on feather T 3 concentration might have obscured any effect of Hg., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Sugarcane management practices include the application of pesticides, including the herbicide 2,4-D and the insecticide fipronil. In addition, a by-product from the ethanol industry, called vinasse, is commonly applied to fertilize sugarcane areas. The potential risks of these practices to the edge-of-field aquatic ecosystems were assessed in the present study. This was done by contaminating mesocosms with (single and mixtures of) both pesticides and vinasse and evaluating the effects on the midge Chironomus sancticaroli through in-situ and laboratory bioassays. To this end, outdoor mesocosms were treated with fipronil (F), 2,4-D (D), and vinasse (V) alone and with the mixture of fipronil and 2,4-D (M), as well as with both pesticides and vinasse (MV). C. sancticaroli was deployed in mesocosms before contamination in cages, which were taken out 4- and 8-days-post-contamination. Water and sediment samples were also taken for laboratory bioassays on the first day of contamination, as well as 7-, 14-, 21-, 30-, 45-, and 75-days post-contamination. The responses assessed in subchronic assays (8-day) were survival, growth, head capsule width, development, and mentum deformities. Low survival occurred in the in-situ experiments of all treatments due to the low oxygen levels. In the laboratory tests, effects on survival occurred for F, V, and M over time after exposure to both water and sediment. All organisms died post-exposure to water samples from the MV treatment, even 75-days-post-contamination. Impairments in body length and head capsule width occurred for F, V, and M for water and F, V, M, and MV for sediment samples over time. All treatments increased mentum deformities in exposed larvae for any of the sampling periods. The negative effects observed were more significant in the mixture mesocosms (M and MV), thus indicating increased risks from management practices applying these compounds together or with a short time interval in crops., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Thandy Junio da Silva Pinto reports financial support was provided by State of São Paulo Research Foundation. Juliane Silber schmidt Freitas reports financial support was provided by State of São Paulo Research Foundation. Michiel Adriaan Daam reports financial support was provided by Foundation for Science and Technology. Raquel Aparecida Moreira reports financial support was provided by State of São Paulo Research Foundation., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Amazonian lowland rainforests epitomize, as few other biomes, the terrestrial and freshwater biological diversity of our planet. We provide here a comprehensive description of the larval anurans of Central Amazonia, and their natural history. We base our analyses on fieldwork conducted in six terra-firme rainforest and two várzea floodplain sites during ~60 months between 1990 and 2013, complemented with an examination of museum specimens and a review of published literature. Ninety-nine species of anurans are known to occur in Central Amazonia. Of these, 84 species (85%) have a free-swimming exotrophic larva, six species (6%) have a terrestrial endotrophic larva, one species has a terrestrial exotrophic larva (1%) and another seven species (7%) have direct development of eggs into froglets. The life cycle of one species (1%) remains unknown. We formally describe and illustrate the larval stage of 68 species (i.e., 75% of the species with a known larval stage), five of them previously unkown and nineteen never described for Central Amazonia. We compile, review and update information on species natural history including reproductive modes, habitat use, phenology, and species interactions including diet, predators, competitors and parasites. Finally, we assessed the ecomorphological diversity in the region by the application of a system inspired in Altig & Johnston (1989), later updated by Altig & McDiarmid (1999), which recognizes tadpole guilds based on a combination of morphological and natural history data. Basic scientific information presented in this monograph provide the essential background for further studies on the ecological and evolutionary forces shaping anuran Amazonian assemblages, and their conservation.

Purple Martins (Progne subis) are migratory birds that breed in North America and overwinter and complete their molt in South America. Many of the breeding populations are declining. The eastern North American subspecies of Purple Martin (P. subis subis) comprises >90% of all Purple Martins. This subspecies overwinters and molts in the Amazon Basin, a region that is high in mercury (Hg) contamination, which raises the possibility that observed declines in Purple Martins could be linked to Hg exposure. Exposure to Hg results in numerous and systemic negative health outcomes, including endocrine disruption. Corticosterone (CORT) is a primary modulator of the stress and metabolic axes of vertebrates; thus, it is important in meeting metabolic and other challenges of migration. Because feathers accumulate Hg and hormones while growing, quantification of Hg and CORT in feathers provides an opportunity to retrospectively assess Hg exposure and adrenal activity of birds using minimally invasive methods. We evaluated interrelationships among concentrations of total Hg (THg) and CORT in feathers that grew in the Amazon Basin and body condition (mass, fat score) of these birds in North America. Concentrations of THg in Purple Martin feathers ranged from 1.103 to 8.740 μg/g dw, levels associated with negative physiological impacts in other avian species. Concentrations of CORT did not correlate with THg concentration at the time of feather growth. However, we found evidence that THg concentration may negatively impact the ability of Purple Martins to accumulate fat, which could impair migratory performance and survivorship due to the high energy requirements of migration. This finding suggests potential carryover effects of Hg contamination at the wintering grounds in the Amazon to the summer breeding grounds in North America., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Expansion of sugarcane crops may have contributed to the increased contamination of native habitats in Brazil. Several species of amphibians inhabit ponds formed in flooded farmlands, where pesticide concentrations are usually high. This study evaluated the ecotoxicological effects of the sugarcane pesticides fipronil and 2,4-D, as well as the fertilizer vinasse (isolated and mixed), on physiological responses of Leptodactylus fuscus and Lithobates catesbeianus tadpoles. In situ assays were conducted in mesocosms with concentrations based on the doses recommended by the manufacturer. Vinasse (1.3% dilution) caused 100% tadpoles' mortality immediately after its application. Fipronil and/or 2,4-D altered antioxidant and biotransformation responses, induced neurotoxicity and changed lipid contents in tadpoles. A multivariate approach indicated that the mixture of pesticides induced most of the sublethal effects in both tadpole species, in addition to the isolated fipronil in L. fuscus. Fipronil alone increased glucose-6-phosphate dehydrogenase (G6PDH) activity, decreased acetylcholinesterase (AChE) and total lipid contents, and altered some individual lipid classes (e.g., free fatty acids and acetone-mobile polar lipids) in L. fuscus. The interaction between fipronil and 2,4-D in this species were more evident for lipid contents, although enzymatic alterations in G6PDH, AChE and glutathione-S-transferase (GST) were also observed. In L. catesbeianus, the mixture of pesticides reduced triglycerides and total lipids, as well as increased GST and decreased AChE activities. The detoxifying enzyme carboxylesterase was reduced by 2,4-D (alone or in mixture) in both species. Isolated pesticides also modulated specific lipid classes, suggesting their disruptive action on energy metabolism of tadpoles. Our study showed that fipronil, 2,4-D, and vinasse, individually or mixed, can be harmful to amphibians during their larval phase, causing mortality or impairing their functional responses., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

With the growing use of agrochemicals in Brazil, there is also a growing need for more realistic toxicity assessments that aid in understanding the potential risks of environmental-realistic agrochemical (mixture) exposures in the natural ecosystems. The aim of the present study was therefore to evaluate the lethal and sublethal effects of environmental realistic (single and mixture) concentrations of the pesticides DMA® 806 BR (active ingredient - a.i. 2,4-D) and Regent® 800 WG (a.i. fipronil) and sugarcane vinasse to the Neotropical cladoceran Ceriodaphnia silvestrii. This evaluation was carried out through lethal (survival), sublethal (reproduction and intrinsic rates of population increase - r) and post-exposure (feeding rate and also reproduction) tests conducted in situ and with water from mesocosms contaminated with the recommended doses of these compounds. The results showed high acute toxicity for treatments containing fipronil and vinasse when acting in isolation, with survival rates only returning to control values on the last sampling day (75 days post application). Reproduction of surviving cladocerans was reduced in all treatments until the end of the experiment and were potentiated effect in the mixture of the three test compounds. The intrinsic rates of population increase were reduced in all treatments except the single 2,4-D treatment. Post-exposure feeding rate and reproduction, however, were not impaired under the conditions analyzed. The results show the high toxicity of recommended doses of fipronil and vinasse (and especially their mixture) and the importance of evaluating the risks of agrochemical mixtures at environmental-realistic concentrations., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Current conceptual metacommunity models predict that the consequences of local selective pressures on community structure increase with spatial isolation when species favored by local conditions also have higher dispersal rates. This appears to be the case of freshwater insects in the presence of fish. The introduction of predatory fish can produce trophic cascades in freshwater habitats because fish tend to prey upon intermediate predatory taxa, such as predatory insects, indirectly benefiting herbivores and detritivores. Similarly, spatial isolation can limit dispersal and colonization rates of predatory insects more strongly than of herbivores and detritivores, thus generating similar cascading effects. Here we tested the hypothesis that the effect of introduced predatory fish on insect community structure increases with spatial isolation by conducting a field experiment in artificial ponds that manipulated the presence/absence of fish (the redbreast tilapia) at three different distances from a source wetland. Our results showed that fish have direct negative effects on the abundance of predatory insects but probably have variable net effects on the abundance of herbivores and detritivores because the direct negative effects of predation by fish may offset indirect positive ones. Spatial isolation also resulted in indirect positive effects on the abundance of herbivores and detritivores but this effect was stronger in the absence rather than in the presence of fish so that insect communities diverged more strongly between fish and fishless ponds at higher spatial isolation. We argue that an important additional mechanism, ignored in our initial hypothesis, was that as spatial isolation increases fish predation pressure upon herbivores and detritivores increases due to the relative scarcity of predatory insects, thus dampening the positive effect that spatial isolation confers to lower trophic levels. Our results highlight the importance of considering interspecific variation in dispersal and multiple trophic levels to better understand the processes generating community and metacommunity patterns., (© 2021 by the Ecological Society of America.)

Sugarcane crops management in Brazil includes the use of pesticides, as well as alternative organic fertilizers such as vinasse obtained from waste of the ethanol industry. In order to assess the effects of the environmental contamination generated by such sugarcane practices, this study was aimed to investigate the effects of the pesticides 2,4-Dichlorophenoxyacetic acid (2,4-D) and fipronil, as well as vinasse, on the survival, behavior, and reproduction of the native epibenthic macroinvertebrate Hyalella meinerti through in situ and laboratory experiments. In situ assays were conducted in mesocosms with six treatments, i.e. untreated control, 2,4-D, fipronil, and vinasse, the mixture of the two pesticides, and both pesticides mixed with vinasse. Survival, swimming behavior, and reproduction were evaluated over time post contamination, from 0-96 h (T1) and 7-14 days (T2) through in situ experiments and 30-44 days (T3) and 75-89 days (T4) post contamination by laboratory bioassays with mesocosm water. In the T1 period, survival of H. meinerti was registered only in controls and mesocosms treated with 2,4-D. In the T2 period, treatments containing fipronil and vinasse (isolated or in both mixture treatments) still caused 100 % of mortality. Survival was recorded only in 2,4-D and control treatments, whereas reproduction only occurred in the control. In the T3 period, no survival occurred to fipronil and both mixture treatments. Vinasse and 2,4-D decreased total reproduction in comparison to control. In the T4 period, amphipods survival was detected when exposed to fipronil and its mixture with 2,4-D. However, these same treatments decreased the amplexus rates and total reproduction, with synergism denoted for the pesticide mixture. The swimming activity of males, females, and couples was decreased in surviving organisms exposed to 2,4-D, fipronil, vinasse, and the mixture of pesticides along all experimental periods. Our study showed that the application of fipronil, 2,4-D, and vinasse isolated or mixed at realistic concentrations of actual sugarcane management practices may negatively impact functional responses of indigenous amphipods in natural aquatic systems., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Despite the higher diversity of amphibians and the increasing use of agrochemicals in tropical countries, knowledge on the ecotoxicity of such compounds to tropical amphibians remains very limited. The aim of this study was, therefore, to assess the acute lethal toxicity of three nitrogen salts (ammonium sulphate, sodium nitrate and sodium nitrite) to tadpoles of five tropical frog species: Rhinella ornata, Boana faber, B. pardalis, Physalaemus cuvieri, and P. olfersii. The order of sensitivity to the nitrogen salts for all five species was sodium nitrite > ammonium sulphate > sodium nitrate. There was not a single most sensitive species to all three nitrogen salts. However, differences in generated 4-d LC50 values between the most and least sensitive test species were small (a factor 2 to 6). A comparison with published toxicity values does not suggest an intrinsic higher, or lower, sensitivity of the tropical species tested as compared to their temperate counterparts. Reported nitrogen concentrations in sugarcane fields do not indicate a lethal risk to the amphibian species tested. Chronic-exposure and field studies are recommended to evaluate amphibian sensitivity under environmental-realistic multiple-stressor conditions.

The increasing demand for biofuels favored the expansion of sugarcane and, as a consequence, in the consumption of pesticides in Brazil. Amphibians are subject to pesticide exposure for occurring in or around sugarcane fields, and for breeding at the onset of the rainy season when pesticide consumption is common. We tested the hypothesis that herbicides used in sugarcane crops, although employed for weed control and manipulated at doses recommended by the manufacturers, can cause lethal and sublethal effects on amphibian larvae. Boana pardalis was exposed to glyphosate, ametryn, 2,4-D, metribuzin and acetochlor which account to up to 2/3 of the volume of herbicides employed in sugarcane production. High mortality was observed following prolonged exposure to ametryn (76%), acetochlor (68%) and glyphosate (15%); ametryn in addition significantly reduced activity rates and slowed developmental and growth rates. AChE activity was surprisingly stimulated by glyphosate, ametryn and 2,4-D, and GST activity by ametryn and acetochlor. Some of these sublethal effects, including the decrease in activity, growth and developmental rates, may have important consequences for individual performance for extending the larval period, and hence the risk of dessication, in the temporary and semi-permanent ponds where the species develops. Future studies should seek additional realism towards a risk analysis of the environmental contamination by herbicides through experiments manipulating not only active ingredients but also commercial formulations, as well as interactions among contaminants and other environmental stressors across the entire life cycle of native amphibian species.

Increased use of sugarcane pesticides and their destination to non-target environments in Brazil has generated concerns related to the conservation of more vulnerable groups, such as amphibians. Besides the high skin permeability, tadpoles are constantly restricted to small and ephemeral ponds, where exposure to high concentrations of pesticides in agricultural areas is inevitable. This study evaluated chronic effects caused by sub-lethal concentrations of 2,4-dichlorophenoxyacetic acid herbicide on energy storage, development, respiration rates, swimming performance and avoidance behavior of bullfrog tadpoles (Lithobates catesbeianus). Firstly, we conducted acute toxicity test (96 h) to estipulate sub-lethal concentrations of 2,4-D and evaluate the sensitivity of three tadpoles' species to this herbicide. Results showed that Leptodactylus fuscus presented the lowest LC 50 96 h, 28.81 mg/L, followed by Physalaemus nattereri (143.08 mg/L) and L. catesbeianus (574.52 mg/L). Chronic exposure to 2,4-D (125, 250 and 500 μg/L) delayed metamorphosis and inhibited the growth of tadpoles at concentrations of 125 μg/L. Effects on biochemical reserves showed that 2,4-D increased total hepatic lipids in tadpoles, although some individual lipid classes (e.g. free fatty acids and triglycerides) were reduced. Protein and carbohydrates contents were also impaired by 2,4-D, suggesting a disruption on energy metabolism of amphibians by the herbicide. In addition to biochemical changes, respiration rates and swimming speed were also decreased after chronic exposure to 2,4-D, and these responses appeared to be correlated with the changes detected in the basic energy content. Avoidance test indicated that tadpoles of L. catesbeinus avoided the presence of 2,4-D, however they were unable to detect increasing gradients of the contaminant. Our data showed that chronic exposure to 2,4-D impaired biochemical, physiological and behavioral aspects of tadpoles, which may compromise their health and make them more vulnerable to environmental stressors in natural systems., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Despite the high amphibian biodiversity and increasing pesticide use in tropical countries, knowledge on the sensitivity of tropical amphibians to pesticides remains limited. The aim of this study was to evaluate the acute toxicity of the active ingredients of four of the main herbicides used in Brazilian sugarcane production to tadpoles of two tropical frog species: Physalaemus cuvieri and Hypsiboas pardalis. The calculated 96 h-LC50 (median lethal concentration; in mg a.s./L) values for P. cuvieri and H. pardalis were 4.4 and 7.8 (acetochlor); 15 and <10 (ametryn); 115 and 106 (glyphosate); and 85 and 68 (metribuzin), respectively. These toxicity values demonstrated little interspecies variation and the toxicity of the herbicides appeared to be at least partly related with the respective octanol-water coefficient. Published acute toxicity data of fish and amphibians for herbicides were also compiled from the US-EPA ECOTOX database. These data indicated little difference in herbicide sensitivity between tropical amphibians and both non-tropical amphibians and fish. These findings indicate that temperate (fish and amphibian) herbicide toxicity data are also protective for tropical amphibians. Constraints in such extrapolations and indications for future research are discussed.

Declining body size has been suggested to be a universal response of organisms to rising temperatures, manifesting at all levels of organization and in a broad range of taxa. However, no study to date evaluated whether deforestation-driven warming could trigger a similar response. We studied changes in fish body size, from individuals to assemblages, in streams in Southeastern Amazonia. We first conducted sampling surveys to validate the assumption that deforestation promoted stream warming, and to test the hypothesis that warmer deforested streams had reduced fish body sizes relative to cooler forest streams. As predicted, deforested streams were up to 6 °C warmer and had fish 36% smaller than forest streams on average. This body size reduction could be largely explained by the responses of the four most common species, which were 43-55% smaller in deforested streams. We then conducted a laboratory experiment to test the hypothesis that stream warming as measured in the field was sufficient to cause a growth reduction in the dominant fish species in the region. Fish reared at forest stream temperatures gained mass, whereas those reared at deforested stream temperatures lost mass. Our results suggest that deforestation-driven stream warming is likely to be a relevant factor promoting observed body size reductions, although other changes in stream conditions, like reductions in organic matter inputs, can also be important. A broad scale reduction in fish body size due to warming may be occurring in streams throughout the Amazonian Arc of Deforestation, with potential implications for the conservation of Amazonian fish biodiversity and food supply for people around the Basin.

Diapause is an actively induced dormancy that has evolved in Metazoa to resist environmental stresses. In temperate regions, many diapausing insects overwinter at low temperatures by blocking embryonic, larval or adult development. Despite its Afro-tropical origin, Drosophila melanogaster migrated to temperate regions of Asia and Europe where females overwinter as adults by arresting gonadal development (reproductive diapause) at temperatures <13°C. Recent work in D. melanogaster has implicated the developmental hormones dILPs-2 and/or dILP3, and dILP5, homologues of vertebrate insulin/insulin-like growth factors (IGFs), in reproductive arrest. However, polymorphisms in timeless (tim) and couch potato (cpo) dramatically affect diapause inducibility and these dILP experiments could not exclude this common genetic variation contributing to the diapause phenotype. Here, we apply an extensive genetic dissection of the insulin signaling pathway which allows us to see both enhancements and reductions in egg development that are independent of tim and cpo variations. We show that a number of manipulations dramatically enhance diapause to ~100%. These include ablating, or reducing the excitability of the insulin-producing cells (IPCs) that express dILPs-2,3,5 employing the dilp2,3,5-/- triple mutant, desensitizing insulin signaling using a chico mutation, or inhibiting dILP2 and 5 in the hemolymph by over-expressing Imaginal Morphogenesis Protein-Late 2 (Imp-L2). In addition, triple mutant dilp2,3,5-/- females maintain high levels of diapause even when temperatures are raised in adulthood to 19°C. However at 22°C, these females all show egg development revealing that the effects are conditional on temperature and not a general female sterility. In contrast, over-expression of dilps-2/5 or enhancing IPC excitability, led to levels of ovarian arrest that approached zero, underscoring dILPs-2 and 5 as key antagonists of diapause., Competing Interests: The authors have declared that no competing interests exist.

Agricultural frontiers are dynamic environments characterized by the conversion of native habitats to agriculture. Because they are currently concentrated in diverse tropical habitats, agricultural frontiers are areas where the largest number of species is exposed to hazardous land management practices, including pesticide use. Focusing on the Amazonian frontier, we show that producers have varying access to resources, knowledge, control and reward mechanisms to improve land management practices. With poor education and no technical support, pesticide use by smallholders sharply deviated from agronomical recommendations, tending to overutilization of hazardous compounds. By contrast, with higher levels of technical expertise and resources, and aiming at more restrictive markets, large-scale producers adhered more closely to technical recommendations and even voluntarily replaced more hazardous compounds. However, the ecological footprint increased significantly over time because of increased dosage or because formulations that are less toxic to humans may be more toxic to other biodiversity. Frontier regions appear to be unique in terms of the conflicts between production and conservation, and the necessary pesticide risk management and risk reduction can only be achieved through responsibility-sharing by diverse stakeholders, including governmental and intergovernmental organizations, NGOs, financial institutions, pesticide and agricultural industries, producers, academia and consumers.

Seasonal changes can induce organisms to modify their developmental growth. Many holometabolous insects, especially Lepidoptera, trigger diapause, an "actively induced" dormancy, for overwintering. Diapause is an alternative developmental pathway that reversibly blocks developmental growth during specific transitions and enhances the hibernating potential of the organism. Changes in environmental cues, such as light and temperature, trigger modifications in the levels, or in the timing, of developmental hormones. These in turn switch the developmental trajectory (diapause or direct development), strongly altering larval/pupal growth and inducing the appearance of diapause-bound seasonal morphs (polyphenism). We also discuss an example of vertebrate diapause using the killifish embryo as an example where diapause is an environmentally determined developmental switch analogous to that observed in lepidopteran dormancy. Based on the examples discussed here, we propose that the complex physiological responses leading to diapause might evolve quickly by relatively limited genetic changes in the regulation of hormonal signals that program normal developmental transitions., (© 2013 Elsevier Inc. All rights reserved.)

Non-consumptive effects (NCEs) of predators owing to induced changes in prey traits are predicted to influence the structure of ecological communities. However, evidence of the importance of NCEs is limited primarily to simple systems (e.g. two to four species) over relatively short periods (e.g. less than one generation). We examined the NCEs of a fish predator, arising from phenotypic plasticity in zooplankton prey traits, over multiple generations of a diverse zooplankton community. The presence of fish, caged to remove consumptive effects, strongly influenced zooplankton community structure, through both direct and indirect NCE pathways, altering the abundance of many taxa by magnitudes as large as 3 to 10-fold. Presence of fish affected different species of cladocerans and copepods both positively and negatively. A particularly striking result was the reversal of dominance in copepod taxa: presence of fish reduced the ratio of calanoids to cyclopoids from 6.3 to 0.43. Further, the NCE of fish had a strong negative trophic cascade to zooplankton resources (phytoplankton). To our knowledge, this is the first experiment to show that NCEs can influence the abundance of multiple prey species over time spans of multiple prey generations. Our findings demonstrate that adaptive phenotypic plasticity of individuals can scale-up to affect the structure of ecological communities.

Background: Whether the provision of evidence-based information improves satisfaction with decision-making is unclear., Objective: To examine whether information about risks and benefits of cancer screening leads to a higher satisfaction with the decision that was made., Methods: Randomized mail survey in the general population, among 2333 adults aged 30-60 years. The survey included a hypothetical cancer screening scenario that included varying amounts of information about benefits and risks of screening (factorial randomized design). The decision process was evaluated by a 6 item scale, with scores between 0 (lowest score) and 100 (highest score)., Results: Substantial proportions of respondents "completely agreed" that the decision reflected what was most important to them (61.2%), were satisfied with their decision (56.0%), were certain of their decision (54.1%), thought that the best choice for them was obvious (53.5%) and that the decision was easy to make (44.1%). The Cronbach alpha coefficient of the scale was 0.88, the mean score was 82.5, and the standard deviation 17.5. Providing information about benefits increased the decision evaluation score only modestly (+1.1, p=0.11); in contrast, providing information about risks sharply reduced the score (-5.1, p<0.001). Those who refused the screening test had lower scores than those who accepted the screening test (69.2 versus 85.6, p<0.001)., Conclusions: Contrary to expectations, informing potential participants about the risks of cancer screening lowered their assessment of the decision process., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Daylength perception in temperate zones is a critical feature of insect life histories, and leads to developmental changes for resisting unfavourable seasons. The role of the neuroendocrine axis in the photoperiodic response of insects is discussed in relation to the key organs and molecules that are involved. We also discuss the controversial issue of the possible involvement of the circadian clock in photoperiodicity. Drosophila melanogaster has a shallow photoperiodic response that leads to reproductive arrest in adults, yet the unrivalled molecular genetic toolkit available for this model insect should allow the systematic molecular and neurobiological dissection of this complex phenotype., (Copyright © 2011 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.)

Background: A common weakness of patient satisfaction surveys is a suboptimal participation rate. Some patients may be unable to participate, because of language barriers, physical limitations, or mental problems. As the role of these barriers is poorly understood, we aimed to identify patient characteristics that are associated with non-participation in a patient satisfaction survey., Methodology: At the University Hospitals of Geneva, Switzerland, a patient satisfaction survey is regularly conducted among all adult patients hospitalized for >24 hours on a one-month period in the departments of internal medicine, geriatrics, surgery, neurosciences, psychiatry, and gynaecology-obstetrics. In order to assess the factors associated with non-participation to the patient satisfaction survey, a case-control study was conducted among patients selected for the 2005 survey. Cases (non respondents, n = 195) and controls (respondents, n = 205) were randomly selected from the satisfaction survey, and information about potential barriers to participation was abstracted in a blinded fashion from the patients' medical and nursing charts., Principal Findings: Non-participation in the satisfaction survey was independently associated with the presence of a language barrier (odds ratio [OR] 4.53, 95% confidence interval [CI95%]: 2.14-9.59), substance abuse (OR 3.75, CI95%: 1.97-7.14), cognitive limitations (OR 3.72, CI95%: 1.64-8.42), a psychiatric diagnosis (OR 1.99, CI95%: 1.23-3.23) and a sight deficiency (OR 2.07, CI95%: 0.98-4.36). The odds ratio for non-participation increased gradually with the number of predictors., Conclusions: Five barriers to non-participation in a mail survey were identified. Gathering patient feedback through mailed surveys may lead to an under-representation of some patient subgroups.

Background: Providing comprehensive information about the risks and benefits of cancer screening is ethically necessary, but information about risks may decrease participation. This study explored the impact of information on intended participation using a randomised factorial design., Methods: We conducted a mail survey of 2333 adults living in Geneva, Switzerland. Each participant was given one randomly chosen version of a scenario that described a hypothetical cancer screening test, and was asked whether he or she would accept to undergo screening. The versions varied in terms of the amount of information about risks and benefits., Results: Respondents who received information about risks associated with screening were more likely to refuse participation (odds ratio 2.6 (95% confidence interval (CI) 2.0-3.5)) than those who received minimal information. In contrast, information about benefits had no impact on intended participation (odds ratio 1.0 (95% CI 0.8-1.2)). The impact of information about risks was significantly stronger in women than in men, in respondents who were in poorer health, who have had a doctor visit in the past 6months, those who have had a cancer screening test in the past 3years, and those who reported a high desire for autonomy in medical decisions., Conclusions: Informing potential participants about the risks of screening may reduce participation rates. Enhanced information about the benefits of screening does not counterbalance this effect., (Copyright 2010 Elsevier Ltd. All rights reserved.)

Patients with diabetes and chronic neurological disorders are most commonly "at-risk" with foot problems. The identification of that population is therefore mandatory to prevent severe foot lesions. However, not all health care providers (HCPs) are involved in the screening process in institutions. The authors' aim was to develop and evaluate an educational program for HCP in the field of at-risk foot. All HCPs of the Loëx Hospital (Department of Rehabilitation and Geriatrics, University Hospitals of Geneva) participated in a longitudinal prospective study. Different professions of HCP (doctors, nurses, nursing aides, physiotherapists, occupational therapists, speech-language therapists, and psychologists) attended a structured educational program during a 1-year period based on a specific consultation that the authors developed. During the sessions, risk factors and therapeutic and preventive interventions are discussed with both the patient and care givers. A questionnaire was developed and used to evaluate (1) initial knowledge of HCP in the field of at-risk foot and (2) the impact of the program on the knowledge of HCP 12 months after starting the program. Twelve months after initiating the program, a significant knowledge improvement was noted in all groups of HCP except medical doctors. Nurses presented the most significant rise in knowledge score (P < .001). In conclusion, the consultation is an acceptable and effective form of long-term educational program for HCP in a hospital setting with a huge majority of patients suffering from chronic vascular and neurological conditions and loss of protective pain sensation at the lower limb.

Understanding the factors responsible for generating size variation in cohorts of organisms is important for predicting their population and evolutionary dynamics. We group these factors into two broad classes: those due to scaling relationships between growth and size (size-dependent factors), and those due to individual trait differences other than size (size-independent factors; e.g., morphology, behavior, etc.). We develop a framework predicting that the nonlethal presence of predators can have a strong effect on size variation, the magnitude and sign of which depend on the relative influence of both factors. We present experimental results showing that size-independent factors can strongly contribute to size variation in anuran larvae, and that the presence of a larval dragonfly predator reduced expression of these size-independent factors. Further, a review of a number of experiments shows that the effect of this predator on relative size variation of a cohort ranged from negative at low growth rates to positive at high growth rates. At high growth rates, effects of size-dependent factors predominate, and predator presence causes an increase in the scaling of growth rate with size (larger individuals respond less strongly to predator presence than small individuals). Thus predator presence led to an increase in size variation. In contrast, at low growth rates, size-independent factors were relatively more important, and predator presence reduced expression of these size-independent factors. Consequently, predator presence led to a decrease in size variation. Our results therefore indicate a further mechanism whereby nonlethal predator effects can be manifest on prey species performance. These results have strong implications for both ecological and evolutionary processes. Theoretical studies indicate that changes in cohort size variation can have profound effects on population dynamics and stability, and therefore the mere presence of a predator could have important ecological consequences. Further, changes in cohort size variation can have important evolutionary implications through changes in trait heritability.

The collapse of amphibian populations within pristine reserves worldwide suggests that diffuse, globally distributed factors such as pollution may be a cause of these declines. Nevertheless, cause-effect relationships between pollution and declines have proven difficult to establish at all scales, from local to global. We therefore aimed to quantitatively evaluate the weight of evidence for the role of pollution in global amphibian declines by first quantifying the published research on the effects of pollutants for all amphibian species in the world and then cross-referencing this information with species' biogeographic distribution, range area, and conservation status and with threats to species as summarized in the Global Amphibian Assessment. We found strong biogeographic and related taxonomic research biases, with a few, common, widely distributed generalist species from the northern hemisphere accounting for the majority of studies. Tropical regions, where more species and declines occur, were severely underrepresented in ecotoxicological research; therefore, current knowledge does not permit assessment of the significance of pollution in amphibian declines at a global scale or in regions where most declines occur. Moreover, if broader distributional ranges and occurrence at higher latitudes are correlated with broader environmental tolerances, current knowledge may considerably underestimate the sensitivity of the majority of amphibian species to pollutants. Finally, because species studied represent only a narrow subset of traits that mediate exposure and susceptibility to pollution, the current potential for extrapolation among species, guilds, ontogenetic phases, levels of complexity, habitat types, sites, and regions is weak. Ultimately, to mitigate these research biases and thus improve the basis for risk management, research policy must balance the spatial scale of the problem (global) and the distribution of knowledge (regional) so that biodiversity representation can be increased and regional bioindicators of environmental health can be developed.

A tradeoff affecting the ability to grow under high versus low resource levels has been commonly hypothesized to influence species distributions across resource gradients in a wide variety of taxa. This influence is dependent on individual growth being proportional to traits that affect demographic processes such as mortality. However, data on how individual growth scales with demographic performance are rare. We conducted a mesocosm experiment, and re-analyzed data from a similarly designed field experiment, to examine the relationship between growth and mortality in two tadpole species that segregate across a resource gradient. Overall, environmental conditions leading to faster growth also lead to lower mortality rates. However, species differed in this relationship. Leopard frogs achieved faster growth than wood frogs, but their absolute mortality was greater and increased steeply as growth decreased. Conversely, absolute mortality of wood frogs was lower and less strongly dependent on growth. These interspecific differences suggest a second tradeoff, that between maximizing growth rates or minimizing mortality, with potentially important demographic consequences. Leopard frogs grow faster than wood frogs in productive ponds, but are excluded from unproductive ponds dominated by wood frogs due to accelerating mortality rates with declining realized growth. A review of the literature suggests that in diverse taxa, including plants, microcrustaceans and drosophilids, patterns in mortality are consistent with this tradeoff indicating that the mechanism we demonstrate could be a link between individual performance and demographic rates influencing species distributions in other systems.

The Authors describe the usefulness of the additional radiologic investigations (stratigraphy and computed tomography) in the study of the back acetabular fractures. The larger information supplied by such investigation about the anatomopathological picture of said fractures allows surgeon to plot the intervention in all details, exactly controlling the remote results.

The authors after remembered shortly, mechanical and biological factors which can determine beginning of carpus scaphoid pseudoarthrosis, described the surgical techniques more frequently used confirmed the important idea of the stable osteosynthesis for a recovery fast and completely.

The rational and selective use of the perioperative antibiotic prophylaxis plays a decisive role in prevention of post-operative infections in orthopedic surgery and traumatology. The conceptual bases for the application of the Short-Term chemioprophylaxis are presented in accord to the most recent data reported in the literature.

Authors describe after a review of literature a case of Osteopoecilia, a rare localized Osteosclerosis Syndrome.

Authors describes a new simplified approach of dorsal sectioning of the distal phalanx, with the suture of the nail. That is a simple method of treatment and its give a good results.

Authors report a preliminary results of omo and ethero-neuro grafts in rats and rabbit.

After recalling some anatomical aspects (with particular reference to the diaphysary vascularization), the authors determine the limits of the conservative treatment of leg fractures, and then describe the surgical techniques they used in the different types of leg fracture. The authors point out the treatment of such fractures does not follow rigid patterns, but it should be chosen case by case after a careful evaluation of general and local factors.

After some short anatomo-physiologic notes, the Authors study the methods of treatment of talus fractures, and determine the different indications thereof. The Authors conclude both the conservative and surgical treatment supply concrete chances of recovery, provided, depending on type and place of fracture, they ensure the articular firmness and vascularization of bone.

After presentation of statistical data on the incidence of osteoid osteoma, a case of femoral neck localization is presented with details of medical history, clinical data, and X-Ray aspects. The operation itself is also described with anatomo-pathological and histological results. These data and the problems of differential diagnosis from other bone tumours is discussed.

Authors report a case of so called Proximal Femoral Focal Deficiency. After remembered different classifications, histological, clinic and radiological findings of this anomaly and analyzed some aspect of the treatment.