Do attacks by jaguars Panthera onca and pumas Puma concolor (Carnivora: Felidae) on livestock correlate with species richness and relative abundance of wild prey? / ¿Se correlacionan los ataques de jaguares Panthera onca y pumas Puma concolor (Carnivora: Felidae) al ganado con la riqueza de especies y la abundancia relativa de presas silvestres?

Attacks by big cats on livestock are one of the major causes of human-felid conflicts and, therefore, an important factor in the conservation of these species. It has been argued that a reduction in natural prey abundance promotes attacks on domestic species, but few studies have tested this statement, and some have delivered contradictory results. We investigated whether the occurrence of attacks to livestock by jaguar and puma relates to the abundance and richness of their natural prey. In the rainy season 2009, we tracked potential prey species counting signs of presence along linear transects in 14 non-attacked cattle farms (control) and in 14 attacked cattle farms in NW Costa Rica. There was a negative relationship between the occurrence of attacks and both species richness (p=0.0014) and abundance (p=0.0012) of natural prey. Our results support the establishment of actions to promote support and recovery of natural prey, in order to diminish attacks on livestock, while maintaining jaguar and puma populations. Rev. Biol. Trop. 62 (4): 1459-1467. Epub 2014 December 01.

Los ataques de grandes felinos al ganado son una de las principales causas de conflicto entre humanos y felinos, siendo por ello un tema prioritario para la conservación de estas especies. Se ha argumentado que la reducción en abundancia de presas naturales incrementa la ocurrencia de ataques a las especies domésticas. Sin embargo son pocos los estudios que han evaluado esta afirmación, algunos con resultados contradictorios. Nosotros investigamos cómo la ocurrencia de ataques al ganado, por parte de puma o jaguar, se relaciona con la abundancia y la riqueza de sus presas naturales. Muestreamos las presas potenciales contando los rastros de presencia a lo largo de transectos lineales en 14 fincas sin ataques (control) y en 14 fincas con ataques en el Noroeste de Costa Rica durante la temporada lluviosa de 2009. Encontramos una relación negativa entre la ocurrencia de ataques al ganado y la riqueza (p=0.0014) y abundancia (p=0.0012) de presas naturales. Nuestros resultados respaldan la aplicación de medidas que promuevan el mantenimiento y recuperación de las presas naturales como medida para reducir los ataques al ganado y conservar las poblaciones de puma y jaguar.

Incidence variation of prostate and cervical cancer according to socioeconomic level in the Girona Health Region.

BACKGROUND: The main aim of this study, using a spatial-temporal model, is to analyse the link between a deprivation index and the incidence of prostate and cervical cancer in the Girona Health Region (GHR). METHODS: This is a population-based study which includes all the inhabitants in the GHR in the period 1993-2006. In order to assess prostate/cervical cancer risk, Besag, York and Mollie (BYM)'s spatial-temporal version of the model was used and four random effects were introduced: (non-spatial) unstructured variability, spatial dependency, temporal dependency and spatial-temporal interaction. As an explanatory variable, a deprivation index was introduced at the census tract level. Furthermore, the percentage of the population between 45-64 years of age and over-65 was also considered as explanatory variables. RESULTS: In the case of prostate cancer, all the variables which were introduced into the model showed a significant correlation with the relative risk, except for the second quintile of the deprivation index. Furthermore, as the index increased the correlation became negative and lower. Thus, the correlation between the relative risk and the two age bands proved to be lower, the higher the age was. In the case of cervical cancer, only the correlation between the over-65 age band and the relative risk was found to be statistically significant and positive. CONCLUSIONS: In the case of prostate cancer, the results obtained in the GHR are in line with similar analyses. However, in the case of cervical cancer, no significant relationship between incidences in this location or economic status was found.

Do pre- and post-copulatory sexually selected traits covary in large herbivores?

BACKGROUND: In most species, males compete to gain both matings (via pre-copulatory competition) and fertilizations (via post-copulatory competition) to maximize their reproductive success. However, the quantity of resources devoted to sexual traits is finite, and so males are predicted to balance their investment between pre- and post-copulatory expenditure depending on the expected pay-offs that should vary according to mating tactics. In Artiodactyla species, males can invest in weapons such as horns or antlers to increase their mating gains or in testes mass/sperm dimensions to increase their fertilization efficiency. Moreover, it has been suggested that in these species, males with territory defence mating tactic might preferentially increase their investment in post-copulatory traits to increase their fertilization efficiency whereas males with female defence mating tactic might increase their investment in pre-copulatory sexually selected traits to prevent other males from copulating with females. In this study, we thus test the prediction that male's weapon length (pre-copulatory trait) covaries negatively with relative testes size and/or sperm dimensions (post-copulatory traits) across Artiodactyla using a phylogenetically controlled framework. RESULTS: Surprisingly no association between weapon length and testes mass is found but a negative association between weapon length and sperm length is evidenced. In addition, neither pre- nor post-copulatory traits were found to be affected by male mating tactics. CONCLUSIONS: We propose several hypotheses that could explain why male ungulates may not balance their reproductive investment between pre- and post-copulatory traits.

Do attacks by jaguars Panthera onca and pumas Puma concolor (Carnivora: Felidae) on livestock correlate with species richness and relative abundance of wild prey?

Abstract: Attacks by big cats on livestock are one of the major causes of human-felid conflicts and, therefore, an important factor in the conservation of these species. It has been argued that a reduction in natural prey abundance promotes attacks on domestic species, but few studies have tested this statement, and some have delivered contradictory results. We investigated whether the occurrence of attacks to livestock by jaguar and puma relates to the abundance and richness of their natural prey. In the rainy season 2009, we tracked potential prey species counting signs of presence along linear transects in 14 non-attacked cattle farms (control) and in 14 attacked cattle farms in NW Costa Rica. There was a negative relationship between the occurrence of attacks and both species richness (p = 0.0014) and abundance (p = 0.0012) of natural prey. Our results support the establishment of actions to promote support and recovery of natural prey, in order to diminish attacks on livestock, while maintaining jaguar and puma populations.

Novel communities from climate change.

Climate change is generating novel communities composed of new combinations of species. These result from different degrees of species adaptations to changing biotic and abiotic conditions, and from differential range shifts of species. To determine whether the responses of organisms are determined by particular species traits and how species interactions and community dynamics are likely to be disrupted is a challenge. Here, we focus on two key traits: body size and ecological specialization. We present theoretical expectations and empirical evidence on how climate change affects these traits within communities. We then explore how these traits predispose species to shift or expand their distribution ranges, and associated changes on community size structure, food web organization and dynamics. We identify three major broad changes: (i) Shift in the distribution of body sizes towards smaller sizes, (ii) dominance of generalized interactions and the loss of specialized interactions, and (iii) changes in the balance of strong and weak interaction strengths in the short term. We finally identify two major uncertainties: (i) whether large-bodied species tend to preferentially shift their ranges more than small-bodied ones, and (ii) how interaction strengths will change in the long term and in the case of newly interacting species.

Climate change impacts on body size and food web structure on mountain ecosystems.

The current distribution of climatic conditions will be rearranged on the globe. To survive, species will have to keep pace with climates as they move. Mountains are among the most affected regions owing to both climate and land-use change. Here, we explore the effects of climate change in the vertebrate food web of the Pyrenees. We investigate elevation range expansions between two time-periods illustrative of warming conditions, to assess: (i) the taxonomic composition of range expanders; (ii) changes in food web properties such as the distribution of links per species and community size-structure; and (iii) what are the specific traits of range expanders that set them apart from the other species in the community-in particular, body mass, diet generalism, vulnerability and trophic position within the food web. We found an upward expansion of species at all elevations, which was not even for all taxonomic groups and trophic positions. At low and intermediate elevations, predator : prey mass ratios were significantly reduced. Expanders were larger, had fewer predators and were, in general, more specialists. Our study shows that elevation range expansions as climate warms have important and predictable impacts on the structure and size distribution of food webs across space.

Stand- and tree-level determinants of the drought response of Scots pine radial growth.

Characterizing the responses of key tree species to extreme climatic events may provide important information for predicting future forest responses to increased climatic variability. Here we aimed at determining which tree- and stand-level attributes were more closely associated with the effect of a severe drought on the radial growth of Scots pine, both in terms of immediate impact and recovery after the drought event. Our dataset included tree-ring series from 393 plots located close to the dry limit of the species range. Time series analysis and mixed-effects models were used to study the growth of each tree and its detailed response to a severe drought event that occurred in 1986. Our results showed that the radial growth responses of Scots pine were determined primarily by tree-level characteristics, such as age and previous growth rate, and secondarily by stand basal area and species richness, whereas local climate had a relatively minor effect. Fast-growing trees were more severely affected by the drought and retained proportionally lower growth rates up to three years after the episode. In absolute terms, however, fast-growing trees performed better both during and after the event. Older trees were found to be less resilient to drought. The effect of stand basal area and species richness indicated that competition for resources worsened the effects of drought, and suggested that the effect of interspecific competition may be particularly detrimental during the drought year.

A study of the immunological response to tumor ablation with irreversible electroporation.

Immune cell recruitment during the treatment of sarcoma tumors in mice with irreversible electroporation was studied by immunohistochemistry. Irreversible electroporation is a non-thermal tissue ablation technique in which certain short duration electrical fields are used to permanently permeabilize the cell membrane, presumably through the formation of nanoscale defects in the membrane. Employing irreversible electroporation parameters known to completely ablate the tumors without thermal effects we did not find infiltration of immune cells probably because of the destruction of infiltration routes. We confirm here that immune response is not instrumental in irreversible electroporation efficacy, and we propose that irreversible electroporation may be, therefore, a treatment modality of interest to immunodepressed cancer patients.

[Pharmacological treatment of post-traumatic behavioural disorders]. / Traitement pharmacologique des troubles du comportement post-traumatiques.

OBJECTIVE: Literature review of the data concerning pharmacologic treatment of post-traumatic behavioural disorders. This review is limited to the treatment of agitation, excitation, mood lability, hostility and agressivity as defined by the NRS and excludes pharmacologic treatment of mental slowness, cognitive disorders and depression. METHODS: Medline interrogation using keywords Traumatic Brain Injury, Agitation, Agressivity, Behaviour, Pharmacology, Neuroleptics, Benzodiazepines, Carbamazepine, Valproate, Buspirone, SSRI, Propanolol, Methylphenidate and review of recent contents. The data finally includes 29 original studies. RESULTS: The overall level of evidence is quite low as the data mainly consist in open studies and case reports. These data and data from reviews or didactic articles suggest the efficiency of a variety of treatments. Mood-stabilizing antiepileptics, and specially carbamazepine constitute together with SSRI antidepressants the first choices. Some data suggest efficiency of buspirone, methylphenidate and atypic neuroleptics. Lithium requires close monitoring but is probably efficient. It is difficult to conclude concerning propanolol. CONCLUSION: The available data is in favour of the use of CBZ and SSRI antidepressants. Further studies are required. It is necessary to establish clear evidence of the efficiency of CBZ and assess the effects of methylphenidate, which is almost not prescribed in France.

Clinical evaluation of prior suicide attempts and suicide risk in psychiatric inpatients.

BACKGROUND: In practice psychiatrists rely on their own experience and intuition to evaluate the suicide potential of individual patients, but the algorithms for the decision-making process remain unclear. OBJECTIVES: (1) to establish models for the decision making process for evaluating suicide risk; (2) to simulate the impact of information concerning the number of previous suicide attempts on the clinician's ability to detect patients who performed medically serious suicide attempts (MSSAs). METHODS: Four decision models (linear, dichotomized, hyperbolic, and undifferentiated) depicting the influence of the number of previous suicide attempts on the clinician's recognition of MSSAs in 250 psychiatric inpatients were elicited and tested by a series of discriminant analyses. RESULTS: The dichotomized model ("all or none") was found to be the most efficient in detecting medically serious suicide attempts. CONCLUSION: The "all or none" paradigm seems to be the most appropriate way to evaluate the weight of previous suicide attempts in the decision-making process identifying medically serious suicide attempt patients.

[Heparin induced thrombocytopenia: case report with acute thrombotic complications and literature review]. / Thrombopénie induite par l'héparine : présentation d'une observation avec complications thrombotiques graves et revue de la littérature.

PURPOSE: Review of the frequency, clinical and biological features and treatment of type II heparin-induced thrombocyopenia. METHODS: Case report and literature review. RESULTS: A 65 years old woman received as antithrombotic prophylaxis low molecular weight heparin (LMWH) after prosthetic knee replacement. Day 8, asymptomatic deep vein thrombosis was discovered after systematic echodoppler examination. Curative anticoagulation was started with LMWH. A fall in the platelet count (17 G/L) was noted day 12. Danaparoid was immediately introduced and heparin discontinued. However, day 16 a massive pulmonary embolism occurred which required transfer to an intensive care unit. Danaparoid was changed for lepirudin the same day. It took longer than three weeks for platelet count to return to normal value after heparin discontinuation. The suspicion of heparin-induced thrombocyopenia was confirmed by specific tests. DISCUSSION: HIT type II are rare but life-threatening and thrombosis events are the most frequent complications. The diagnosis is a high probability proved by both clinical and biological patterns. The treatment consists in alternative thrombin inhibitors such as danaparoid and lepirudin. The platelet count usually requires less than ten days to recover normal values after heparin withdrawal. Cases in which the delay to a normal platelet count exceeds 3 weeks have been reported specially after LMWH therapy. CONCLUSION: Type II HIT are rare but life-threatening events can occur. The platelet count check-up during heparin therapy must be systematic.