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1.
Nutrients ; 16(6)2024 Mar 19.
Article in English | MEDLINE | ID: mdl-38542797

ABSTRACT

This paper presents baseline results from the NutriEcoMuscle study, a multicenter observational study conducted in Spain which focused on changes in nutritional status, body composition, and functionality in post-intensive care unit (ICU) COVID-19 patients following a nutritional intervention. Assessments at hospital discharge included Subjective Global Assessment (SGA), Global Leadership Initiative on Malnutrition (GLIM) criteria, the Barthel index, handgrip strength (HGS) and the Timed Up-and-Go test, bioelectrical impedance analysis (BIA), and nutritional ultrasound (US). The study involved 96 patients (71.9% male, mean age 58.8 years, mean BMI 28.8 kg/m2, 36.5% obese). All patients were malnourished at discharge according to GLIM and SGA. Functional status declined from admission up to hospital discharge. A total of 33.3% of patients had a low fat-free mass index (FFMI) and 29.5% had a low phase angle (PhA). Myosteatosis was observed in 83.7% of the population. There was a positive correlation between rectus femoris cross-sectional area, PhA, FFMI, and HGS. In conclusion, post-critically ill COVID-19 patients commonly suffer from malnutrition and reduced muscle mass, causing a loss of independence at hospital discharge. BIA and US could be valuable tools for assessing body composition in these patients. The NutriEcoMuscle study highlights the need for a thorough nutritional and morphofunctional status assessment of post-ICU patients.


Subject(s)
COVID-19 , Malnutrition , Humans , Male , Middle Aged , Female , Nutrition Assessment , Patient Discharge , Hand Strength , COVID-19/complications , Nutritional Status , Malnutrition/epidemiology , Intensive Care Units , Hospitals
2.
Article in English | MEDLINE | ID: mdl-38509722

ABSTRACT

Carrion ecology, i.e. the decomposition and recycling of dead animals, has traditionally been neglected as a key process in ecosystem functioning. Similarly, despite the large threats that inland aquatic ecosystems (hereafter, aquatic ecosystems) face, the scientific literature is still largely biased towards terrestrial ecosystems. However, there has been an increasing number of studies on carrion ecology in aquatic ecosystems in the last two decades, highlighting their key role in nutrient recirculation and disease control. Thus, a global assessment of the ecological role of scavengers and carrion in aquatic ecosystems is timely. Here, we systematically reviewed scientific articles on carrion ecology in aquatic ecosystems to describe current knowledge, identify research gaps, and promote future studies that will deepen our understanding in this field. We found 206 relevant studies, which were highly biased towards North America, especially in lotic ecosystems, covering short time periods, and overlooking seasonality, a crucial factor in scavenging dynamics. Despite the low number of studies on scavenger assemblages, we recorded 55 orders of invertebrates from 179 families, with Diptera and Coleoptera being the most frequent orders. For vertebrates, we recorded 114 species from 40 families, with birds and mammals being the most common. Our results emphasise the significance of scavengers in stabilising food webs and facilitating nutrient cycling within aquatic ecosystems. Studies were strongly biased towards the assessment of the ecosystem effects of carrion, particularly of salmon carcasses in North America. The second most common research topic was the foraging ecology of vertebrates, which was mostly evaluated through sporadic observations of carrion in the diet. Articles assessing scavenger assemblages were scarce, and only a limited number of these studies evaluated carrion consumption patterns, which serve as a proxy for the role of scavengers in the ecosystem. The ecological functions performed by carrion and scavengers in aquatic ecosystems were diverse. The main ecological functions were carrion as food source and the role of scavengers in nutrient cycling, which appeared in 52.4% (N = 108) and 46.1% (N = 95) of publications, respectively. Ecosystem threats associated with carrion ecology were also identified, the most common being water eutrophication and carrion as source of pathogens (2.4%; N = 5 each). Regarding the effects of carrion on ecosystems, we found studies spanning all ecosystem components (N = 85), from soil or the water column to terrestrial vertebrates, with a particular focus on aquatic invertebrates and fish. Most of these articles found positive effects of carrion on ecosystems (e.g. higher species richness, abundance or fitness; 84.7%; N = 72), while a minority found negative effects, changes in community composition, or even no effects. Enhancing our understanding of scavengers and carrion in aquatic ecosystems is crucial to assessing their current and future roles amidst global change, mainly for water-land nutrient transport, due to changes in the amount and speed of nutrient movement, and for disease control and impact mitigation, due to the predicted increase in occurrence and magnitude of mortality events in aquatic ecosystems.

3.
Sci Rep ; 12(1): 17843, 2022 10 25.
Article in English | MEDLINE | ID: mdl-36284169

ABSTRACT

A reduction in adult survival in long-living species may compromise population growth rates. The spur-thighed tortoise (Testudo graeca) is a long-lived reptile that is threatened by habitat loss and fragmentation. Golden eagles (Aquila chrysaetos), whose breeding habitats overlap that of tortoises, may predate them by dropping them onto rocks and breaking their carapaces. In SE Spain, the number of golden eagles has increased in the last decades and the abundance of their main prey (i.e., rabbits Oryctolagus cuniculus) has decreased. Our aims were to 1) describe the role of tortoises in golden eagles' diet, and 2) estimate the predation impact of golden eagles on tortoises in eagles' territories and in the regional tortoise population. We collected regurgitated pellets and prey remains under eagle nests and roosts, and obtained information on tortoise abundance and population structure and rabbit abundance. We found that tortoises were an alternative prey to rabbits, so that eagles shifted to the former where the latter were scarce. The average predation rate on tortoises was very low at the two studied scales. However, eagles showed a marked selection for adult female tortoises, which led the tortoise sex ratio to be biased towards males in those eagle territories with higher tortoise predation. Whether this may compromise the spur-thighed tortoise long-term population viability locally deserves further attention.


Subject(s)
Eagles , Turtles , Animals , Male , Female , Predatory Behavior , Ecosystem
4.
Ecol Evol ; 12(8): e9133, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35923937

ABSTRACT

Invasive Alien Species (IAS) alter ecosystems, disrupting ecological processes and driving the loss of ecosystem services. The common carp Cyprinus carpio is a hazardous and widespread IAS, becoming the most abundant species in many aquatic ecosystems. This species transforms ecosystems by accumulating biomass to the detriment of other species, thus altering food webs. However, some terrestrial species, such as vertebrate scavengers, may benefit from dead carps, by incorporating part of the carp biomass into the terrestrial environment. This study describes the terrestrial vertebrate scavenger assemblage that benefits from carp carcasses in a Mediterranean wetland. We also evaluate the seasonal differences in the scavenger assemblage composition and carrion consumption patterns. Eighty carp carcasses (20 per season) were placed in El Hondo Natural Park, a seminatural mesohaline wetland in south-eastern Spain, and we monitored their consumption using camera traps. We recorded 14 scavenger species (10 birds and four mammals) consuming carp carcasses, including globally threatened species. Vertebrates consumed 73% of the carrion biomass and appeared consuming at 82% of the carcasses. Of these carcasses consumed, 75% were completely consumed and the mean consumption time of carcasses completely consumed by vertebrates was 44.4 h (SD = 42.1 h). We recorded differences in species richness, abundance, and assemblage composition among seasons, but we did not find seasonal differences in consumption patterns throughout the year. Our study recorded a rich and efficient terrestrial vertebrate scavenger assemblage benefitting from carp carcasses. We detected a seasonal replacement on the scavenger species, but a maintenance of the ecological function of carrion removal, as the most efficient carrion consumers were present throughout the year. The results highlight the importance of vertebrate scavengers in wetlands, removing possible infectious focus, and moving nutrients between aquatic and terrestrial environments.

5.
Sci Total Environ ; 801: 149652, 2021 Dec 20.
Article in English | MEDLINE | ID: mdl-34438159

ABSTRACT

Nature's contributions to people (NCP) may be both beneficial and detrimental to humans' quality of life. Since our origins, humans have been closely related to wild ungulates, which have traditionally played an outstanding role as a source of food or raw materials. Currently, wild ungulates are declining in some regions, but recovering in others throughout passive rewilding processes. This is reshaping human-ungulate interactions. Thus, adequately understanding the benefits and detriments associated with wild ungulate populations is necessary to promote human-ungulate co-existence. Here, we reviewed 575 articles (2000-2019) on human-wild ungulate interactions to identify key knowledge gaps on NCP associated with wild ungulates. Wild ungulate research was mainly distributed into seven research clusters focussing on: (1) silvicultural damage in Eurasia; (2) herbivory and natural vegetation; (3) conflicts in urban areas of North America; (4) agricultural damage in Mediterranean agro-ecosystems; (5) social research in Africa and Asia; (6) agricultural damage in North America; (7) research in natural American Northwest areas. Research mostly focused on detrimental NCP. However, the number of publications mentioning beneficial contributions increased after the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services conceptual framework was implemented. Human-ungulate interactions' research was biased towards the Global North and Cervidae, Suidae and Bovidae families. Regarding detrimental NCP, most publications referred to production damage (e.g. crops), followed by biodiversity damage, and material damage (e.g. traffic collisions). Regarding beneficial NCP, publications mainly highlighted non-material contributions (e.g. recreational hunting), followed by material NCP and regulating contributions (e.g. habitat creation). The main actions taken to manage wild ungulate populations were lethal control and using deterrents and barriers (e.g. fencing), which effectiveness was rarely assessed. Increasing research and awareness about beneficial NCP and effective management tools may help to improve the conservation of wild ungulates and the ecosystems they inhabit to facilitate people-ungulate co-existence in the Anthropocene.


Subject(s)
Deer , Ecosystem , Animals , Biodiversity , Herbivory , Humans , Quality of Life , Ruminants , Swine
6.
Ecology ; 102(12): e03519, 2021 12.
Article in English | MEDLINE | ID: mdl-34449876

ABSTRACT

Species assemblages often have a non-random nested organization, which in vertebrate scavenger (carrion-consuming) assemblages is thought to be driven by facilitation in competitive environments. However, not all scavenger species play the same role in maintaining assemblage structure, as some species are obligate scavengers (i.e., vultures) and others are facultative, scavenging opportunistically. We used a database with 177 vertebrate scavenger species from 53 assemblages in 22 countries across five continents to identify which functional traits of scavenger species are key to maintaining the scavenging network structure. We used network analyses to relate ten traits hypothesized to affect assemblage structure with the "role" of each species in the scavenging assemblage in which it appeared. We characterized the role of a species in terms of both the proportion of monitored carcasses on which that species scavenged, or scavenging breadth (i.e., the species "normalized degree"), and the role of that species in the nested structure of the assemblage (i.e., the species "paired nested degree"), therefore identifying possible facilitative interactions among species. We found that species with high olfactory acuity, social foragers, and obligate scavengers had the widest scavenging breadth. We also found that social foragers had a large paired nested degree in scavenger assemblages, probably because their presence is easier to detect by other species to signal carcass occurrence. Our study highlights differences in the functional roles of scavenger species and can be used to identify key species for targeted conservation to maintain the ecological function of scavenger assemblages.


Subject(s)
Falconiformes , Food Chain , Animals , Fishes , Phenotype , Vertebrates
7.
Nutr. hosp ; 38(n.extr.1): 41-45, abr. 2021.
Article in English | IBECS | ID: ibc-201895

ABSTRACT

The debate from the course preceding the SENPE (Spanish Society of Clinical Nutrition and Metabolism) 2020 Conference gathered together well-known professionals who form part of nutritional support teams (NSTs), as well as other specialists from departments whose patients benefit from the services offered by these NSTs. In this article, relevant points from the round table, including strengths and weaknesses detected in the implementation of nutrition support teams, are summarized


El debate del curso previo al congreso de la Sociedad Española de Nutrición Clínica y Metabolismo (SENPE) 2020 reunió en una mesa redonda a profesionales de prestigio que forman parte de unidades de nutrición y dietética, y a otros especialistas de servicios cuyos pacientes se benefician de los servicios de estas unidades. En este artículo se muestran los puntos relevantes que se trataron en el mismo y se muestran algunas fortalezas y debilidades que se han detectado en la implementación de las unidades de nutrición


Subject(s)
Humans , Focus Groups , Pandemics , Coronavirus Infections/diet therapy , Nutritional Support , Societies, Medical/organization & administration , Health Personnel/organization & administration , Health Plan Implementation/organization & administration , Diet Therapy/methods
8.
Geroscience ; 43(3): 1465-1479, 2021 06.
Article in English | MEDLINE | ID: mdl-33449308

ABSTRACT

Overweight and obesity are well-known independent risk factors for stroke in the general population although uncertain in the case of the elderly, according to the obesity paradox. Little is known about underlying mechanisms. Our study aims to assess whether there is a relationship between excess body weight (measured as waist circumference) and poor cerebral hemodynamics (measured by transcranial Doppler parameters: basal, mean flow velocity (MFV), and dynamic, cerebrovascular reserve (CvR) in the right middle cerebral artery (RMCA)). A possible underlying molecular mechanism was analyzed via plasma leptin, adiponectin, TNF-α, IL-6, VCAM, and CRP levels. One hundred sixty-five subjects were included. Bivariate and multivariate regression showed a linear correlation between waist circumference and hemodynamics in RMCA, with clear gender effects: MFV (global NS, men ß - 0.26 p < 0.01; women NS), CvR (global: ß - 0.15 p < 0.01; men: ß - 0.29 p < 0.01, women: ß - 0.19 p < 0.09). For subjects above 65 years, there is no significant relationship between AbP and cerebral hemodynamics. In multivariate regression models, only leptin correlated independently with MFV in RMCA (ß 7.24, p < 0.01) and CvR (ß - 0.30, p < 0.01). In both cases, waist circumference remains significantly related to both parameters. There is an inverse linear correlation between excess body weight and cerebral hemodynamics, independent of other vascular risk factors and clearly influenced by gender. This relation disappears in the elderly population. Leptin might play a role in this relationship. Nevertheless, there must be another associated mechanism, not identified in this study.


Subject(s)
Adipokines , Ultrasonography, Doppler, Transcranial , Aged , Female , Hemodynamics , Humans , Male , Obesity/complications , Waist Circumference
9.
Ecol Evol ; 10(4): 1938-1948, 2020 Feb.
Article in English | MEDLINE | ID: mdl-32128127

ABSTRACT

Mate searching is a key component of sexual reproduction that can have important implications for population viability, especially for the mate-finding Allee effect. Interannual sperm storage by females may be an adaptation that potentially attenuates mate limitation, but the demographic consequences of this functional trait have not been studied. Our goal is to assess the effect of female sperm storage durability on the strength of the mate-finding Allee effect and the viability of populations subject to low population density and habitat alteration. We used an individual-based simulation model that incorporates realistic representations of the demographic and spatial processes of our model species, the spur-thighed tortoise (Testudo graeca). This allowed for a detailed assessment of reproductive rates, population growth rates, and extinction probabilities. We also studied the relationship between the number of reproductive males and the reproductive rates for scenarios combining different levels of sperm storage durability, initial population density, and landscape alteration. Our results showed that simulated populations parameterized with the field-observed demographic rates collapsed for short sperm storage durability, but were viable for a durability of one year or longer. In contrast, the simulated populations with a low initial density were only viable in human-altered landscapes for sperm storage durability of 4 years. We find that sperm storage is an effective mechanism that can reduce the strength of the mate-finding Allee effect and contribute to the persistence of low-density populations. Our study highlights the key role of sperm storage in the dynamics of species with limited movement ability to facilitate reproduction in patchy landscapes or during population expansion. This study represents the first quantification of the effect of sperm storage durability on population dynamics in different landscapes and population scenarios.

10.
Endocrinol. diabetes nutr. (Ed. impr.) ; 66(10): 654-662, dic. 2019.
Article in Spanish | IBECS | ID: ibc-184793

ABSTRACT

Las enfermedades endocrinas están experimentando un importante incremento de su prevalencia, debido a causas de diversa índole, entre ellas la epidemia de obesidad y de desnutrición, el envejecimiento de la población, pero también el efecto de los disruptores endocrinos, entre otros. Por otra parte, las nuevas tecnologías, tanto a nivel de analítica molecular y genética, de imagen y de nuevos dispositivos terapéuticos, obligan a que la comunidad profesional endocrina en España tenga que estar en constante formación. La conexión con los pacientes a través de sus asociaciones, cada vez más activas, y con la sociedad civil en general, el compromiso profesional y la demanda de diversos colectivos sociales de una atención moderna y equitativa, y a llevar a cabo investigación que facilite la consecución de avances para los pacientes, obligan al especialista en Endocrinología y Nutrición, y a la Sociedad Española de Endocrinología y Nutrición (SEEN), a posicionarse y dar respuesta a todos estos retos. En el presente documento, la SEEN expone sus propuestas y su estrategia hasta el 2022


Endocrine diseases are experiencing an important increase in their prevalence, due to causes of various kinds, including the epidemic of obesity and malnutrition, the aging of the population, but also the effect of endocrine disruptors, among others. On the other hand, new technologies, both in terms of molecular and genetic analysis, image and new therapeutic devices, require that the endocrine professional community in Spain must be in constant training. The connection with patients through their associations, increasingly active, and with the civil society in general, the professional commitment and demand of various social groups for a modern and equitable care, and to carry out research that facilitates the achievement of advances for patients, forces the specialist in endocrinology and nutrition and the Spanish Society of Endocrinology and Nutrition (SEEN) to position themselves and respond to all these challenges. In this document, the SEEN presents its proposals and its strategy until 2022


Subject(s)
Endocrinology/organization & administration , Societies, Medical/organization & administration , Societies, Medical/trends , Health Strategies , Endocrinology/trends , National Health Systems , Medicine/organization & administration , Health Promotion , Spain
11.
Endocrinol Diabetes Nutr (Engl Ed) ; 66(10): 654-662, 2019 Dec.
Article in English, Spanish | MEDLINE | ID: mdl-31272927

ABSTRACT

Endocrine diseases are experiencing an important increase in their prevalence, due to causes of various kinds, including the epidemic of obesity and malnutrition, the aging of the population, but also the effect of endocrine disruptors, among others. On the other hand, new technologies, both in terms of molecular and genetic analysis, image and new therapeutic devices, require that the endocrine professional community in Spain must be in constant training. The connection with patients through their associations, increasingly active, and with the civil society in general, the professional commitment and demand of various social groups for a modern and equitable care, and to carry out research that facilitates the achievement of advances for patients, forces the specialist in endocrinology and nutrition and the Spanish Society of Endocrinology and Nutrition (SEEN) to position themselves and respond to all these challenges. In this document, the SEEN presents its proposals and its strategy until 2022.


Subject(s)
Endocrinology/trends , Nutritional Sciences/trends , Societies, Medical , Forecasting , Spain , Time Factors
12.
Environ Res ; 176: 108543, 2019 09.
Article in English | MEDLINE | ID: mdl-31260915

ABSTRACT

BACKGROUND: Intensification of agricultural practices has caused several negative effects to the environment. The use of fertilizers and pesticides may alter geochemical cycles or cause direct wildlife intoxication. Detrimental effects of organochlorine pesticides (OCPs) have forced the authorities to ban or restrict its use. This study evaluates the variation in levels of OCPs in a sentinel species in relation to changes in government regulations and the spatial configuration of agricultural practices around the nests. METHODS: Between 2003 and 2007, we analysed OCP levels in 256 blood samples of Eurasian Eagle-owl (Bubo bubo) chicks nesting in area of intensive commercial agriculture with historical frequent use of pesticides, in South-eastern Spain. We studied year-to-year variations in OCP concentrations and their relation with land use configuration around raptor nests by Generalized Linear Mixed Models (GLMM). RESULTS: OCPs were detected in 100% samples surveyed in 2003 and 2004, while dropped to 27% in 2005, 6.8% in 2006 and 6.3% in 2007, coinciding with the ban of OCPs. The presence of the main OCPs was related to agricultural practices. In particular, endosulfan and lindane were related to irrigated crops and urban areas, while DDT-related compounds and dieldrin were associated with dry land farming. CONCLUSIONS: OCP concentrations in blood samples of Eurasian Eagle-owls may respond quickly to the implementations of new regulations about the use of agricultural products. This raptor was confirmed as a good sentinel species allowing rapid detection of changes in pesticides use.


Subject(s)
Environmental Monitoring , Hydrocarbons, Chlorinated , Pesticides , Agriculture , Government Regulation , Spain
13.
Glob Chang Biol ; 25(9): 3005-3017, 2019 09.
Article in English | MEDLINE | ID: mdl-31127672

ABSTRACT

Understanding the distribution of biodiversity across the Earth is one of the most challenging questions in biology. Much research has been directed at explaining the species latitudinal pattern showing that communities are richer in tropical areas; however, despite decades of research, a general consensus has not yet emerged. In addition, global biodiversity patterns are being rapidly altered by human activities. Here, we aim to describe large-scale patterns of species richness and diversity in terrestrial vertebrate scavenger (carrion-consuming) assemblages, which provide key ecosystem functions and services. We used a worldwide dataset comprising 43 sites, where vertebrate scavenger assemblages were identified using 2,485 carcasses monitored between 1991 and 2018. First, we evaluated how scavenger richness (number of species) and diversity (Shannon diversity index) varied among seasons (cold vs. warm, wet vs. dry). Then, we studied the potential effects of human impact and a set of macroecological variables related to climatic conditions on the scavenger assemblages. Vertebrate scavenger richness ranged from species-poor to species rich assemblages (4-30 species). Both scavenger richness and diversity also showed some seasonal variation. However, in general, climatic variables did not drive latitudinal patterns, as scavenger richness and diversity were not affected by temperature or rainfall. Rainfall seasonality slightly increased the number of species in the community, but its effect was weak. Instead, the human impact index included in our study was the main predictor of scavenger richness. Scavenger assemblages in highly human-impacted areas sustained the smallest number of scavenger species, suggesting human activity may be overriding other macroecological processes in shaping scavenger communities. Our results highlight the effect of human impact at a global scale. As species-rich assemblages tend to be more functional, we warn about possible reductions in ecosystem functions and the services provided by scavengers in human-dominated landscapes in the Anthropocene.


Subject(s)
Biodiversity , Ecosystem , Animals , Climate , Fishes , Humans , Vertebrates
14.
Sensors (Basel) ; 17(7)2017 Jul 22.
Article in English | MEDLINE | ID: mdl-28737693

ABSTRACT

The main causes of building defects are errors in the design and the construction phases. These causes related to construction are mainly due to the general lack of control of construction work and represent approximately 75% of the anomalies. In particular, one of the main causes of such anomalies, which end in building defects, is the lack of control over the physical variables of the work environment during the execution of tasks. Therefore, the high percentage of defects detected in buildings that have the root cause in the construction phase could be avoidable with a more accurate and efficient control of the process. The present work proposes a novel integration model based on information and communications technologies for the automation of both construction work and its management at the execution phase, specifically focused on the flat roof construction process. Roofs represent the second area where more defects are claimed. The proposed model is based on a Web system, supported by a service oriented architecture, for the integral management of tasks through the Last Planner System methodology, but incorporating the management of task restrictions from the physical environment variables by designing specific sensing systems. Likewise, all workers are integrated into the management process by Internet-of-Things solutions that guide them throughout the execution process in a non-intrusive and transparent way.

15.
Sci Rep ; 7(1): 4019, 2017 06 22.
Article in English | MEDLINE | ID: mdl-28642457

ABSTRACT

Human-mediated secondary contact of recently diverged taxa offers valuable opportunities for studying the evolutionary mechanisms involved in the establishment and maintenance of genetic boundaries between taxa. We used mitochondrial and microsatellite markers to examine a recently introduced population of the spur-thighed tortoise (Testudo graeca) of mixed origin in the Doñana National Park (SW Spain). The earliest records of tortoises in Doñana trace back to the 18th century, but several population reinforcements in the 20th century with animals from Morocco are well-documented. Consequently, different genetic lineages, which represent distinct subspecies, are thought to co-exist there. Our results confirmed the presence of distinct lineages by revealing that tortoises of the subspecies T. g. marokkensis were introduced into a local allochthonous T. g. graeca population. Unexpectedly, T. g. marokkensis haplotypes exclusively appeared in males, and admixture levels were statistically sex-biased toward males. The sex ratio of the population deviated from parity, with males being 2.36-fold more abundant than females. Our results indicated that population reinforcements had a strong effect on the genetic composition of this population and aggravated its sex ratio deviation. We predict that this sex-biased pattern of introgression is ephemeral and advocated to the near loss of T. g. marokkensis haplotypes.


Subject(s)
Genetics, Population , Turtles/classification , Turtles/genetics , Africa, Northern , Animals , Europe , Evolution, Molecular , Genetic Variation , Haplotypes , Humans , Microsatellite Repeats
16.
Eur Phys J C Part Fields ; 77(12): 865, 2017.
Article in English | MEDLINE | ID: mdl-31997938

ABSTRACT

In the presence of quantum-gravity fluctuations (space-time foam), the CPT operator may be ill-defined. Its perturbative treatment leads to a modification of the Einstein-Podolsky-Rosen correlation of the neutral meson system by adding an entanglement-weakening term of the wrong exchange symmetry, the ω -effect. In the current paper we identify how to probe the complex ω in the entangled B d -system using the flavour (f)-CP(g) eigenstate decay channels: the connection between the intensities for the two time-ordered decays (f, g) and (g, f) is lost. Appropriate observables are constructed allowing independent experimental determinations of Re( ω ) and Im( ω ), disentangled from CPT violation in the evolution Hamiltonian Re( θ ) and Im( θ ). 2 σ tensions for both Re( θ ) and Im( ω ) are shown to be uncorrelated.

17.
Ecology ; 97(1): 95-105, 2016 Jan.
Article in English | MEDLINE | ID: mdl-27008779

ABSTRACT

Disentangling the processes that shape the organization of ecological assemblages and its implications for species coexistence is one of the foremost challenges of ecology. Although insightful advances have recently related community composition and structure with species coexistence in mutualistic and antagonistic networks, little is known regarding other species assemblages, such as those of scavengers exploiting carrion. Here we studied seven assemblages of scavengers feeding on ungulate carcasses in mainland Spain. We used dynamical models to investigate if community composition, species richness and structure (nestedness) affect species coexistence at carcasses. Scavenging networks showed a nested pattern in sites where highly efficient, obligate scavengers (i.e., vultures) were present and a non-nested pattern everywhere else. Griffon Vulture (Gyps fulvus) and certain meso-facultative mammalian scavengers (i.e., red fox, Vulpes vulpes, and stone marten, Martes foina) were the main species contributing to nestedness. Assemblages with vultures were also the richest ones in species. Nested species-rich assemblages with vulture presence were associated with high carcass consumption rates, indicating higher interspecific competition at the local scale. However, the proportion of species stopping the consumption of carrion (as derived from the competitive dynamic model) stabilized at high richness and nestedness levels. This suggests that high species richness and nestedness may characterize scavenging networks that are robust to high levels of interspecific competition for carrion. Some facilitative interactions driven by vultures and major facultative scavengers could be behind these observations. Our findings are relevant for understanding species' coexistence in highly competitive systems.


Subject(s)
Biodiversity , Carnivora/physiology , Competitive Behavior , Falconiformes/physiology , Feeding Behavior , Animals , Food Chain , Models, Biological , Population Dynamics , Spain
20.
PLoS One ; 10(7): e0133954, 2015.
Article in English | MEDLINE | ID: mdl-26230922

ABSTRACT

The study of the demographic history of species can help to understand the negative impact of recent population declines in organisms of conservation concern. Here, we use neutral molecular markers to explore the genetic consequences of the recent population decline and posterior recovery of the Eurasian eagle owl (Bubo bubo) in the Iberian Peninsula. During the last century, the species was the object of extermination programs, suffering direct persecution by hunters until the 70's. Moreover, during the last decades the eagle owl was severely impacted by increased mortality due to electrocution and the decline of its main prey species, the European rabbit (Oryctolagus cuniculus). In recent times, the decrease of direct persecution and the implementation of some conservation schemes have allowed the species' demographic recovery. Yet, it remains unknown to which extent the past population decline and the later expansion have influenced the current species' pattern of genetic diversity. We used eight microsatellite markers to genotype 235 eagle owls from ten Spanish subpopulations and analyse the presence of genetic signatures attributable to the recent population fluctuations experienced by the species. We found moderate levels of differentiation among the studied subpopulations and Bayesian analyses revealed the existence of three genetic clusters that grouped subpopulations from central, south-western and south-eastern Spain. The observed genetic structure could have resulted from recent human-induced population fragmentation, a patchy distribution of prey populations and/or the philopatric behaviour and habitat selection of the species. We detected an old population bottleneck, which occurred approximately 10,000 years ago, and significant signatures of recent demographic expansions. However, we did not find genetic signatures for a recent bottleneck, which may indicate that population declines were not severe enough to leave detectable signals on the species genetic makeup or that such signals have been eroded by the rapid demographic recovery experienced by the species in recent years.


Subject(s)
Predatory Behavior , Strigiformes/physiology , Animals , Conservation of Natural Resources , Genetic Variation , Spain , Strigiformes/genetics
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