Seasonal Effects of Habitat on Sources and Rates of Snowshoe Hare Predation in Alaskan Boreal Forests

PubMed Central

Feierabend, Dashiell; Kielland, Knut

2015-01-01

Survival and predation of snowshoe hares (Lepus americanus) has been widely studied, yet there has been little quantification of the changes in vulnerability of hares to specific predators that may result from seasonal changes in vegetation and cover. We investigated survival and causes of mortalities of snowshoe hares during the late increase, peak, and decline of a population in interior Alaska. From June 2008 to May 2012, we radio-tagged 288 adult and older juvenile hares in early successional and black spruce (Picea mariana) forests and, using known-fate methods in program MARK, evaluated 85 survival models that included variables for sex, age, and body condition of hares, as well as trapping site, month, season, year, snowfall, snow depth, and air temperature. We compared the models using Akaike’s information criterion with correction for small sample size. Model results indicated that month, capture site, and body condition were the most important variables in explaining survival rates. Survival was highest in July, and more generally during summer, when alternative prey was available to predators of hares. Low survival rates coincided with molting periods, breeding activity in the spring, and the introduction of juveniles to the sample population in the fall. We identified predation as the cause of mortality in 86% of hare deaths. When the source of predation could be determined, hares were killed more often by goshawks (Accipiter gentilis) than other predators in early successional forest (30%), and more often by lynx (Lynx canadensis) than other predators in black spruce forest (31%). Great horned owls (Bubo virginianus) and coyotes (Canis latrans) represented smaller proportions of hare predation, and non-predatory causes were a minor source (3%) of mortality. Because hares rely on vegetative cover for concealment from predators, we measured cover in predation sites and habitats that the hares occupied and concluded that habitat type had a greater influence on the sources of predation than the amount of cover in any given location within a habitat. Our observations illustrate the vulnerability of hares to predators in even the densest coniferous habitat available in the boreal forest, and indicate strong seasonal changes in the rates and sources of predation. PMID:26717577

Spillover Events of Infection of Brown Hares (Lepus europaeus) with Rabbit Haemorrhagic Disease Type 2 Virus (RHDV2) Caused Sporadic Cases of an European Brown Hare Syndrome-Like Disease in Italy and Spain.

PubMed

Velarde, R; Cavadini, P; Neimanis, A; Cabezón, O; Chiari, M; Gaffuri, A; Lavín, S; Grilli, G; Gavier-Widén, D; Lavazza, A; Capucci, L

2017-12-01

Rabbit haemorrhagic disease virus (RHDV) is a lagovirus that can cause fatal hepatitis (rabbit haemorrhagic disease, RHD) with mortality of 80-90% in farmed and wild rabbits. Since 1986, RHDV has caused outbreaks in rabbits (Oryctolagus cuniculus) in Europe, but never in European brown hares (Lepus europaeus, EBH). In 2010, a new RHDV-related virus, called RHDV2, emerged in Europe, causing extended epidemics because it largely overcame the immunity to RHDV present in most rabbit populations. RHDV2 also was identified in Cape hare (Lepus capensis subsp. mediterraneus) and in Italian hare (Lepus corsicanus). Here, we describe two distinct incidents of RHDV2 infection in EBH that occurred in Italy (2012) and Spain (2014). The two RHDV2 strains caused macroscopic and microscopic lesions similar to European brown hare syndrome (EBHS) in hares, and they were genetically related to other RHDV2 strains in Europe. EBHs are common in Europe, often sharing habitat with rabbits. They likely have been exposed to high levels of RHDV2 during outbreaks in rabbits in recent years, yet only two incidents of RHDV2 in EBHs have been found in Italy and Spain, suggesting that EBHs are not a primary host. Instead, they may act as spillover hosts in situations when infection pressure is high and barriers between rabbits and hares are limited, resulting in occasional infections causing EBHS-like lesions. The serological survey of stocked hare sera taken from Italian and Spanish hare populations provided an understanding of naturally occurring RHDV2 infection in the field confirming its sporadic occurrence in EBH. Our findings increase the knowledge on distribution, host range and epidemiology of RHDV2. © 2016 The Authors. Transboundary and Emerging Diseases Published by Blackwell Verlag GmbH.

Space-use, diet, demographics, and topographic associations of lynx in the southern Canadian Rocky Mountains: A study [Chapter 12

Treesearch

Clayton D. Apps

2000-01-01

Snowshoe hares are considered the primary prey of Canada lynx throughout their range. Relative to northern populations, hares occurring in mountainous regions at southern latitudes are thought to remain at low and stable densities through time. Hence, the ecology of associated southern lynx populations is expected to resemble that of northern populations during the low...

Variation of partial transferrin sequences and phylogenetic relationships among hares (Lepus capensis, Lagomorpha) from Tunisia.

PubMed

Awadi, Asma; Suchentrunk, Franz; Makni, Mohamed; Ben Slimen, Hichem

2016-10-01

North African hares are currently included in cape hares, Lepus capensis sensu lato, a taxon that may be considered a superspecies or a complex of closely related species. The existing molecular data, however, are not unequivocal, with mtDNA control region sequences suggesting a separate species status and nuclear loci (allozymes, microsatellites) revealing conspecificity of L. capensis and L. europaeus. Here, we study sequence variation in the intron 6 (468 bp) of the transferrin nuclear gene, of 105 hares with different coat colour from different regions in Tunisia with respect to genetic diversity and differentiation, as well as their phylogenetic status. Forty-six haplotypes (alleles) were revealed and compared phylogenetically to all available TF haplotypes of various Lepus species retrieved from GenBank. Maximum Likelihood, neighbor joining and median joining network analyses concordantly grouped all currently obtained haplotypes together with haplotypes belonging to six different Chinese hare species and the African scrub hare L. saxatilis. Moreover, two Tunisian haploypes were shared with L. capensis, L timidus, L. sinensis, L. yarkandensis, and L. hainanus from China. These results indicated the evolutionary complexity of the genus Lepus with the mixing of nuclear gene haplotypes resulting from introgressive hybridization or/and shared ancestral polymorphism. We report the presence of shared ancestral polymorphism between North African and Chinese hares. This has not been detected earlier in the mtDNA sequences of the same individuals. Genetic diversity of the TF sequences from the Tunisian populations was relatively high compared to other hare populations. However, genetic differentiation and gene flow analyses (AMOVA, F ST , Nm) indicated little divergence with the absence of geographically meaningful phylogroups and lack of clustering with coat colour types. These results confirm the presence of a single hare species in Tunisia, but a sound inference on its phylogenetic position would require additional nuclear markers and numerous geographically meaningful samples from Africa and Eurasia.

Mammals and habitat disturbance: the case of brown hare and wildfire.

PubMed

Sokos, Christos; Birtsas, Periklis; Papaspyropoulos, Konstantinos G; Tsachalidis, Efstathios; Giannakopoulos, Alexios; Milis, Chrysostomos; Spyrou, Vassiliki; Manolakou, Katerina; Valiakos, George; Iakovakis, Christos; Athanasiou, Labrini V; Sfougaris, Athanasios; Billinis, Charalambos

2016-10-01

Ecosystem disturbances, such as wildfires, are driving forces that determine ecology and conservation measures. Species respond differentially to wildfires, having diverse post-fire population evolution. This study reports, for first time, the responses of brown hare ( Lepus europaeus Pallas, 1778) to wildfires. Hare relative abundance, age ratio, diet quality, body condition, and diseases were studied. Fire influence on vegetation was calculated at a micro-scale level. Hare abundance was lower the first year after wildfires in burned relative to unburned areas. The reverse was found in the second year when hare abundance was higher in burned areas. Hare abundance in burned areas was also higher in the third and fourth years. In the fifth and sixth years after wildfire no significant difference was found in abundance. At a micro-scale level, higher numbers of hare feces were counted in places with greater wildfire influence on vegetation. Age ratio analysis revealed more juveniles in burned areas, but the same number of neonates in burned and unburned areas, indicating lower mortality of juveniles in burned areas. Reduced predation in burned areas provides the most plausible explanation for our findings.

Efficacies of prevention and control measures applied during an outbreak in Southwest Madrid, Spain

PubMed Central

Martcheva, Maia; Tuncer, Necibe; Fontana, Isabella; Carrillo, Eugenia; Moreno, Javier; Keesling, James

2017-01-01

Leishmaniasis is a vector-borne disease of worldwide distribution, currently present in 98 countries. Since late 2010, an unusual increase of human visceral and cutaneous leishmaniasis cases has been observed in the south-western Madrid region, totaling more than 600 cases until 2015. Some hosts, such as human, domestic dog and cat, rabbit (Oryctolagus cuniculus), and hare (Lepus granatensis), were found infected by the parasite of this disease in the area. Hares were described as the most important reservoir due to their higher prevalence, capacity to infect the vector, and presence of the same strains as in humans. Various measures were adopted to prevent and control the disease, and since 2013 there was a slight decline in the human sickness. We used a mathematical model to evaluate the efficacy of each measure in reducing the number of infected hosts. We identified in the present model that culling both hares and rabbits, without immediate reposition of the animals, was the best measure adopted, decreasing the proportion of all infected hosts. Particularly, culling hares was more efficacious than culling rabbits to reduce the proportion of infected individuals of all hosts. Likewise, lowering vector contact with hares highly influenced the reduction of the proportion of infected hosts. The reduction of the vector density per host in the park decreased the leishmaniasis incidence of hosts in the park and the urban areas. On the other hand, the reduction of the vector density per host of the urban area (humans, dogs and cats) decreased only their affected population, albeit at a higher proportion. The use of insecticide-impregnated collar and vaccination in dogs affected only the infected dogs’ population. The parameters related to the vector contact with dog, cat or human do not present a high impact on the other hosts infected by Leishmania. In conclusion, the efficacy of each control strategy was determined, in order to direct future actions in this and in other similar outbreaks. The present mathematical model was able to reproduce the leishmaniasis dynamics in the Madrid outbreak, providing theoretical support based on successful experiences, such as the reduction of human cases in Southwest Madrid, Spain. PMID:29028841

Efficacies of prevention and control measures applied during an outbreak in Southwest Madrid, Spain.

PubMed

Sevá, Anaiá da Paixão; Martcheva, Maia; Tuncer, Necibe; Fontana, Isabella; Carrillo, Eugenia; Moreno, Javier; Keesling, James

2017-01-01

Leishmaniasis is a vector-borne disease of worldwide distribution, currently present in 98 countries. Since late 2010, an unusual increase of human visceral and cutaneous leishmaniasis cases has been observed in the south-western Madrid region, totaling more than 600 cases until 2015. Some hosts, such as human, domestic dog and cat, rabbit (Oryctolagus cuniculus), and hare (Lepus granatensis), were found infected by the parasite of this disease in the area. Hares were described as the most important reservoir due to their higher prevalence, capacity to infect the vector, and presence of the same strains as in humans. Various measures were adopted to prevent and control the disease, and since 2013 there was a slight decline in the human sickness. We used a mathematical model to evaluate the efficacy of each measure in reducing the number of infected hosts. We identified in the present model that culling both hares and rabbits, without immediate reposition of the animals, was the best measure adopted, decreasing the proportion of all infected hosts. Particularly, culling hares was more efficacious than culling rabbits to reduce the proportion of infected individuals of all hosts. Likewise, lowering vector contact with hares highly influenced the reduction of the proportion of infected hosts. The reduction of the vector density per host in the park decreased the leishmaniasis incidence of hosts in the park and the urban areas. On the other hand, the reduction of the vector density per host of the urban area (humans, dogs and cats) decreased only their affected population, albeit at a higher proportion. The use of insecticide-impregnated collar and vaccination in dogs affected only the infected dogs' population. The parameters related to the vector contact with dog, cat or human do not present a high impact on the other hosts infected by Leishmania. In conclusion, the efficacy of each control strategy was determined, in order to direct future actions in this and in other similar outbreaks. The present mathematical model was able to reproduce the leishmaniasis dynamics in the Madrid outbreak, providing theoretical support based on successful experiences, such as the reduction of human cases in Southwest Madrid, Spain.

Mammals and habitat disturbance: the case of brown hare and wildfire

PubMed Central

Sokos, Christos; Birtsas, Periklis; Papaspyropoulos, Konstantinos G.; Tsachalidis, Efstathios; Giannakopoulos, Alexios; Milis, Chrysostomos; Spyrou, Vassiliki; Manolakou, Katerina; Valiakos, George; Iakovakis, Christos; Athanasiou, Labrini V.; Sfougaris, Athanasios; Billinis, Charalambos

2016-01-01

Abstract Ecosystem disturbances, such as wildfires, are driving forces that determine ecology and conservation measures. Species respond differentially to wildfires, having diverse post-fire population evolution. This study reports, for first time, the responses of brown hare (Lepus europaeus Pallas, 1778) to wildfires. Hare relative abundance, age ratio, diet quality, body condition, and diseases were studied. Fire influence on vegetation was calculated at a micro-scale level. Hare abundance was lower the first year after wildfires in burned relative to unburned areas. The reverse was found in the second year when hare abundance was higher in burned areas. Hare abundance in burned areas was also higher in the third and fourth years. In the fifth and sixth years after wildfire no significant difference was found in abundance. At a micro-scale level, higher numbers of hare feces were counted in places with greater wildfire influence on vegetation. Age ratio analysis revealed more juveniles in burned areas, but the same number of neonates in burned and unburned areas, indicating lower mortality of juveniles in burned areas. Reduced predation in burned areas provides the most plausible explanation for our findings. PMID:29491931

Snowshoe hare multi-level habitat use in a fire-adapted ecosystem

USGS Publications Warehouse

Gigliotti, Laura C.; Jones, Benjamin C.; Lovallo, Matthew J.; Diefenbach, Duane R.

2018-01-01

Prescribed burning has the potential to improve habitat for species that depend on pyric ecosystems or other early successional vegetation types. For species that occupy diverse plant communities over the extent of their range, response to disturbances such as fire might vary based on post-disturbance vegetation dynamics among plant communities. Although responses of snowshoe hares (Lepus americanus) to fire have been studied in conifer-dominated forests in northern parts of the species’ range, there is a lack of information on snowshoe hare habitat use in fire-dependent communities in southern parts of their range. We used global positioning system (GPS) and very high frequency (VHF) radio-collars to monitor the habitat use of 32 snowshoe hares in a scrub-oak (Quercus ilicifolia)-pitch pine (Pinus rigida) barrens complex in northeastern Pennsylvania where prescribed fire has been used for habitat restoration. The area contained stands that underwent prescribed burning 1–6 years prior to our study. Also, we investigated fine-scale determinants of habitat use within stands. We found that regardless of season, hares did not select for areas that had been burned within 6 years prior. Hares primarily used stands of older scrub oak, conifer, or hardwoods, which contained dense understory vegetation and canopy cover. Hare habitat use also was positively associated with stand edges. Our results suggest that hares do not respond to prescribed burning of scrub oak in the short-term. In addition, by focusing on structural determinants of habitat use, rather than broad-scale characteristics such as stand type, management strategies for snowshoe hares can be adapted over the extent of their range despite the multitude of different land cover types across which the species occurs. 

The ecology of snowshoe hares in northern boreal forests [Chapter 6

Treesearch

Karen E. Hodges

2000-01-01

Snowshoe hares exhibit eight to 11 year population fluctuations across boreal North America, typically with an amplitude of 10 to 25 fold. These fluctuations are synchronous across the continent, with the most recent peak densities occurring in 1990 and 1991. The numeric cycle is driven by changes in survival and reproduction, with annual survival of adults...

Activity of Selected Antioxidant Enzymes, Selenium Content and Fatty Acid Composition in the Liver of the Brown Hare (Lepus europaeus L.) in Relation to the Season of the Year.

PubMed

Drozd, Radosław; Pilarczyk, Renata; Pilarczyk, Bogumiła; Drozd, Arleta; Tomza-Marciniak, Agnieszka; Bombik, Teresa; Bąkowska, Małgorzata; Bombik, Elżbieta; Jankowiak, Dorota; Wasak, Agata

2015-12-01

The aim of the study was to evaluate the effect of low concentrations of selenium in the environment on the activity of selected antioxidant enzymes: Se-GSHPx, total GSHPx, SOD, CAT, and GST as well as fatty acid profile in the livers of brown hares during winter and spring. Liver tissues obtained from 20 brown hares collected in the north-eastern Poland in the winter and spring season were analyzed. In the tissue analyzed, a significantly lower level of selenium was noticeable in the spring compared to winter; however, values measured in both seasons indicated a deficiency of this element in the analyzed population of brown hares. There were no differences found that could indicate the influence of Se deficiency on the activity of antioxidant enzymes. The determined activity of antioxidant enzymes and fatty acid composition suggest a negligible impact of the low concentration of Se on the analyzed biochemical parameters of brown hare livers.

Project Roadkill: Linking European Hare vehicle collisions with landscape-structure using datasets from citizen scientists and professionals

NASA Astrophysics Data System (ADS)

Stretz, Carina; Heigl, Florian; Steiner, Wolfgang; Bauer, Thomas; Suppan, Franz; Zaller, Johann G.

2015-04-01

Road networks can implicate lots of negative effects for wildlife. One of the most important indication for strong landscape fragmentation are roadkills, i.e. collisions between motorised vehicles and wild animals. A species that is often involved in roadkills is the European hare (Lepus europaeus). European hare populations are in decline throughout Europe since the 1960s and classified as "potentially endangered" in the Red Data Book of Austria. Therefore, it is striking that in the hunting year 2013/14, 19,343 hares were killed on Austrian roads translating to 53 hare roadkills each day, or rather about two per hour. We hypothesized, that (I) hare-vehicle-collisions occur as an aggregation of events (hotspot), (II) the surrounding landscape influences the number of roadkilled hares and (III) roadkill data from citizen science projects and data from professionals (e.g. hunters, police) are convergent. Investigations on the surrounding landscape of the scenes of accidents will be carried out using land cover data derived from Landsat satellite images. Information on road kills are based on datasets from two different sources. One dataset stems from the citizen science project "Roadkill" (www.citizen-science.at/roadkill) where participants report roadkill findings via a web application. The second dataset is from a project where roadkill data were collected by the police and by hunters. Besides answering our research questions, findings of this project also allow the location of dangerous roadkill hotspots for animals and could be implemented in nature conservation actions.

Use of the Personality Assessment Inventory to assess psychopathy in offender populations.

PubMed

Edens, J F; Hart, S D; Johnson, D W; Johnson, J K; Olver, M E

2000-06-01

The authors investigated the validity of the Antisocial Features (ANT) scale of the Personality Assessment Inventory (PAI; L. C. Morey, 1991) with respect to assessments of psychopathy in 2 offender samples. Study 1 included 46 forensic psychiatric inpatients who were administered the Screening Version of the Hare Psychopathy Checklist (PCL:SV; S. D. Hart, D. N. Cox, & R. D. Hare, 1995). In Study 2, 55 sex offenders were administered the Hare Psychopathy Checklist--Revised (PCL-R; R. D. Hare, 1991). ANT scores correlated highly with the PCL:SV total score (r = .54) and moderately with the PCL-R total score (r = .40). ANT tapped primarily behavioral symptoms of psychopathy rather than interpersonal and affective symptoms. Also, ANT had low to moderate diagnostic efficiency regarding diagnoses of psychopathy, suggesting that it may be better used as a dimensional rather than categorical measure of this construct.

Using experimentation to understand the 10-year snowshoe hare cycle in the boreal forest of North America.

PubMed

Krebs, Charles J; Boonstra, Rudy; Boutin, Stan

2018-01-01

Population cycles have long fascinated ecologists from the time of Charles Elton in the 1920s. The discovery of large population fluctuations in undisturbed ecosystems challenged the idea that pristine nature was in a state of balance. The 10-year cycle of snowshoe hares (Lepus americanus Erxleben) across the boreal forests of Canada and Alaska is a classic cycle, recognized by fur traders for more than 300 years. Since the 1930s, ecologists have investigated the mechanisms that might cause these cycles. Proposed causal mechanisms have varied from sunspots to food supplies, parasites, diseases, predation and social behaviour. Both the birth rate and the death rate change dramatically over the cycle. Social behaviour was eliminated as a possible cause because snowshoe hares are not territorial and do not commit infanticide. Since the 1960s, large-scale manipulative experiments have been used to discover the major limiting factors. Food supply and predation quickly became recognized as potential key factors causing the cycle. Experiments adding food and restricting predator access to field populations have been decisive in pinpointing predation as the key mechanism causing these fluctuations. The immediate cause of death of most snowshoe hares is predation by a variety of predators, including the Canada lynx (Lynx canadensis Kerr). The collapse in the reproductive rate is not due to food shortage as was originally thought, but is a result of chronic stress from predator chases. Five major issues remain unresolved. First, what is the nature of the predator-induced memory that results in the prolonged low phase of the cycle? Second, why do hare cycles form a travelling wave, starting in the centre of the boreal forest in Saskatchewan and travelling across western Canada and Alaska? Third, why does the amplitude of the cycle vary greatly from one cycle to the next in the same area? Fourth, do the same mechanisms of population limitation apply to snowshoe hares in eastern North American or in similar ecosystems across Siberia? Finally, what effect will climatic warming have on all the above issues? The answers to these questions remain for future generations of biologists to determine. © 2017 The Authors. Journal of Animal Ecology © 2017 British Ecological Society.

The rise and fall of the mountain hare (Lepus timidus) during Pleistocene glaciations: expansion and retreat with hybridization in the Iberian Peninsula.

PubMed

Melo-Ferreira, J; Boursot, P; Randi, E; Kryukov, A; Suchentrunk, F; Ferrand, N; Alves, P C

2007-02-01

The climatic fluctuations during glaciations have affected differently arctic and temperate species. In the northern hemisphere, cooling periods induced the expansion of many arctic species to the south, while temperate species were forced to retract in southern refugia. Consequently, in some areas the alternation of these species set the conditions for competition and eventually hybridization. Hares in the Iberian Peninsula appear to illustrate this phenomenon. Populations of Iberian hare (Lepus granatensis), brown hare (Lepus europaeus) and broom hare (Lepus castroviejoi) in Northern Iberia harbour mitochondrial haplotypes from the mountain hare (Lepus timidus), a mainly boreal and arctic species presently absent from the peninsula. To understand the history of this past introgression we analysed sequence variation and geographical distribution of mitochondrial control region and cytochrome b haplotypes of L. timidus origin found in 378 specimens of these four species. Among 124 L. timidus from the Northern Palaearctic and the Alps we found substantial nucleotide diversity (2.3%) but little differentiation between populations. Based on the mismatch distribution of the L. timidus sequences, this could result from an expansion at a time of temperature decrease favourable to this arctic species. The nucleotide diversity of L. timidus mtDNA found in Iberian L. granatensis, L. europaeus and L. castroviejoi (183, 70 and 1 specimens, respectively) was of the same order as that in L. timidus over its range (1.9%), suggesting repeated introgression of multiple lineages. The structure of the coalescent of L. granatensis sequences indicates that hybridization with L. timidus was followed by expansion of the introgressed haplotypes, as expected during a replacement with competition, and occurred when temperatures started to rise, favouring the temperate species. Whether a similar scenario explains the introgression into Iberian L. europaeus remains unclear but it is possible that it hybridized with already introgressed L. granatensis.

Modeling individual movement decisions of brown hare (Lepus europaeus) as a key concept for realistic spatial behavior and exposure: A population model for landscape-level risk assessment.

PubMed

Kleinmann, Joachim U; Wang, Magnus

2017-09-01

Spatial behavior is of crucial importance for the risk assessment of pesticides and for the assessment of effects of agricultural practice or multiple stressors, because it determines field use, exposition, and recovery. Recently, population models have increasingly been used to understand the mechanisms driving risk and recovery or to conduct landscape-level risk assessments. To include spatial behavior appropriately in population models for use in risk assessments, a new method, "probabilistic walk," was developed, which simulates the detailed daily movement of individuals by taking into account food resources, vegetation cover, and the presence of conspecifics. At each movement step, animals decide where to move next based on probabilities being determined from this information. The model was parameterized to simulate populations of brown hares (Lepus europaeus). A detailed validation of the model demonstrated that it can realistically reproduce various natural patterns of brown hare ecology and behavior. Simulated proportions of time animals spent in fields (PT values) were also comparable to field observations. It is shown that these important parameters for the risk assessment may, however, vary in different landscapes. The results demonstrate the value of using population models to reduce uncertainties in risk assessment and to better understand which factors determine risk in a landscape context. Environ Toxicol Chem 2017;36:2299-2307. © 2017 SETAC. © 2017 SETAC.

Health screening of free-ranging European brown hares (Lepus europaeus) on the German North-Sea island Pellworm.

PubMed

Posautz, Annika; Loncaric, Igor; Lundin, Marie; Hoffmann, Daniel; Lavazza, Antonio; Kelemen, Zsofia; Beiglböck, Christoph; Walzer, Christian; Kübber-Heiss, Anna

2015-08-04

A sudden decline of the European brown hare (Lepus europaeus) population in one of the best hunting districts for small game species in northern Germany, the German North-Sea island Pellworm, in the years 2007/08 following marked habitat changes led to the implementation of a thorough health assessment program of the population. 110 animals were collected during the normal hunting season in the years 2010 and 2011. A post-mortem examination and histopathological investigation was performed on all animals. Additionally, routine bacteriology of the small intestine and parasitology were carried out. Sera of hares were tested for European Brown Hare Syndrome (EBHS) by enzyme linked immunosorbent assay, and for Treponema sp. by indirect immunofluorescent test. Additional testing was performed when deemed necessary. The most striking result was a shift in the intestinal bacterial flora towards Gram-negative Enterobacteriaceae with a predominance of either Escherichia coli, or Aeromonas sp., or a high-grade double-infection with these two pathogens with subsequent catarrhal enteritis. Additionally, a marked coccidiosis, and varying infestations with the nematode Trichostrongylus retortaeformis were found. The sero-prevalence for EBHS was 78.1%, and for Treponema 43.9%. The shift and decrease in diversity of the intestinal flora was the main and most consistent result found. In the authors' opinion the change of the habitat combined with other stressors increased the animals' sensitivity to ubiquitous bacterial species and parasites which usually would not have such fatal effects.

Genetic relatedness of Brucella suis biovar 2 isolates from hares, wild boars and domestic pigs.

PubMed

Kreizinger, Zsuzsa; Foster, Jeffrey T; Rónai, Zsuzsanna; Sulyok, Kinga M; Wehmann, Enikő; Jánosi, Szilárd; Gyuranecz, Miklós

2014-08-27

Porcine brucellosis generally manifests as disorders in reproductive organs potentially leading to serious losses in the swine industry. Brucella suis biovar 2 is endemic in European wild boar (Sus scrofa) and hare (Lepus europeus, Lepus capensis) populations, thus these species may play a significant role in disease spread and serve as potential sources of infection for domestic pigs. The aim of this study was an epidemiologic analysis of porcine brucellosis in Hungary and a comparative analysis of B. suis bv. 2 strains from Europe using multiple-locus variable-number tandem repeat analysis (MLVA). MLVA-16 and its MLVA-11 subset were used to determine the genotypes of 68 B. suis bv. 2 isolates from Hungary and results were then compared to European MLVA genotypes. The analyses indicated relatively high genetic diversity of B. suis bv. 2 in Hungary. Strains isolated from hares and wild boars from Hungary showed substantial genetic divergence, suggesting separate lineages in each host and no instances of cross species infections. The closest relatives of strains from Hungarian wild boars and domestic pigs were mainly in the isolates from German and Croatian boars and pigs. The assessment of the European MLVA genotypes of wild boar isolates generally showed clustering based on geographic origin. The hare strains were relatively closely related to one another and did not cluster based on geographic origin. The limited relationships between geographic origin and genotype in isolates from hares might be the result of cross-border live animal translocation. The results could also suggest that certain B. suis strains are more adapted to hares. Across Europe, isolates from domestic pigs were closely related to isolates originating from both hares and wild boars, supporting the idea that wild animals are a source of brucellosis in domestic pigs. Copyright © 2014 Elsevier B.V. All rights reserved.

Septicemic listeriosis in wild hares from Saskatchewan, Canada.

PubMed

Rothenburger, Jamie L; Bennett, Katarina R; Bryan, Lorraine; Bollinger, Trent K

2015-04-01

The bacterium Listeria monocytogenes causes disease in a wide variety of mammals including rabbits and hares. We describe naturally acquired metritis and septicemic listeriosis in wild female hares from Saskatchewan, Canada. Between April 2012 and July 2013, two white-tailed jackrabbits (Lepus townsendii) and a snowshoe hare (Lepus americanus) were presented to the Veterinary Medical Centre at the Western College of Veterinary Medicine, Saskatoon, Saskatchewan, Canada with nonspecific neurologic signs. The hares were euthanized and autopsied. Necrotizing fibrinosuppurative metritis was present in all. Additional findings in individual hares included fetal maceration, multifocal necrotizing myocarditis, multifocal hepatic necrosis, and nonsuppurative encephalitis. Listeria monocytogenes was cultured from multiple tissues in each hare. Although listeriosis in pregnant domestic rabbits has been studied, this is the first detailed description in wild North American hares. The epidemiology of listeriosis, including prevalence and the role of environmental sources and coprophagy in transmission among hares, requires further investigation.

The sensitive hare: sublethal effects of predator stress on reproduction in snowshoe hares.

PubMed

Sheriff, Michael J; Krebs, Charles J; Boonstra, Rudy

2009-11-01

1. Prey responses to high predation risk can be morphological or behavioural and ultimately come at the cost of survival, growth, body condition, or reproduction. These sub-lethal predator effects have been shown to be mediated by physiological stress. We tested the hypothesis that elevated glucocorticoid concentrations directly cause a decline in reproduction in individual free-ranging female snowshoe hares, Lepus americanus. We measured the cortisol concentration from each dam (using a faecal analysis enzyme immunoassay) and her reproductive output (litter size, offspring birth mass, offspring right hind foot (RHF) length) 30 h after birth. 2. In a natural monitoring study, we monitored hares during the first and second litter from the population peak (2006) to the second year of the decline (2008). We found that faecal cortisol metabolite (FCM) concentration in dams decreased 52% from the first to the second litter. From the first to the second litter, litter size increased 122%, offspring body mass increased 130%, and offspring RHF length increased 112%. Dam FCM concentrations were inversely related to litter size (r(2) = 0.19), to offspring birth mass (r(2) = 0.32), and to offspring RHF length (r(2) = 0.64). 3. In an experimental manipulation, we assigned wild-caught, pregnant hares to a control and a stressed group and held them in pens. Hares in the stressed group were exposed to a dog 1-2 min every other day before parturition to simulate high predation risk. At parturition, unsuccessful-stressed dams (those that failed to give birth to live young) and stressed dams had 837% and 214%, respectively, higher FCM concentrations than control dams. Of those females that gave birth, litter size was similar between control and stressed dams. However, offspring from stressed dams were 37% lighter and 16% smaller than offspring from control dams. Increasing FCM concentration in dams caused the decline of offspring body mass (r(2) = 0.57) and RHF (r(2) = 0.52). 4. This is the first study in a free-ranging population of mammals to show that elevated, predator-induced, glucocorticoid concentrations in individual dams caused a decline in their reproductive output measured both by number and quality of offspring. Thus, we provide evidence that any stressor, not just predation, which increases glucocorticoid concentrations will result in a decrease in reproductive output.

Use of non-invasive genetics to generate core-area population estimates of a threatened predator in the Superior National Forest, USA

USGS Publications Warehouse

Barber-Meyer, Shannon; Ryan, Daniel; Grosshuesch, David; Catton, Timothy; Malick-Wahls, Sarah

2018-01-01

core areas and averaged 52.3 (SD=8.3, range=43-59) during 2015-2017 in the larger core areas. We found no evidence for a decrease or increase in abundance during either period. Lynx density estimates were approximately 7-10 times lower than densities of lynx in northern populations at the low of the snowshoe hare (Lepus americanus) population cycle. To our knowledge, our results are the first attempt to estimate abundance, trend and density of lynx in Minnesota using non-invasive genetic capture-mark-recapture. Estimates such as ours provide useful benchmarks for future comparisons by providing a context with which to assess 1) potential changes in forest management that may affect lynx recovery and conservation, and 2) possible effects of climate change on the depth, density, and duration of annual snow cover and correspondingly, potential effects on snowshoe hares as well.

Fleas, lice and mites on scrub hares (Lepus saxatilis) in northern and eastern Transvaal and in KwaZulu-Natal, South Africa.

PubMed

Louw, J P; Horak, I G; Horak, M L; Braack, L E

1995-06-01

Fleas, lice and mites were collected from 24 and 120 scrub hares at Pafuri and Skukuza, Northern and Eastern Transvaal, respectively, in the Kruger National Park, and from 34 scrub hares in the Hluhluwe region, north-eastern KwaZulu-Natal. Ctenocephalides felis damarensis, the only flea recovered, reached peak burdens on the hares at each locality during late winter or spring. Juvenile hares harboured significantly fewer fleas than did adult animals. The lice Haemodipsus lyriocephalus and Haemodipsus setoni were collected from hares at each locality, with H. setoni generally being the most abundant. Listrophorus leporicolus was found on hares at Skukuza and Hluhluwe, and mites of the genus Cheyletiella were collected from hares at Skukuza.

DNA markers for identifying individual snowshoe hares using field-collected pellets

Treesearch

Michael K. Schwartz; Kristine L. Pilgrim; Kevin S. McKelvey; Pilar T. Rivera; Leonard F. Ruggiero

2007-01-01

Snowshoe hare (Lepus americanus) abundance has been of interest to wildlife biologists, as hares are essential prey items for many rare and endangered predators. Snowshoe hare abundance has most commonly been estimated through indices such as pellet counts. While pellet counts may be useful in the areas they are developed and when hares are dense,...

Spatio-temporal dynamics of tularemia in French wildlife: 2002-2013.

PubMed

Moinet, Marie; Decors, Anouk; Mendy, Christiane; Faure, Eva; Durand, Benoit; Madani, Nora

2016-08-01

Tularemia, caused by Francisella tularensis, is endemic in France. The surveillance of this disease in wildlife is operated by the SAGIR Network and by the National Reference Laboratory for Tularemia. Wild animals found dead or dying collected by the SAGIR network are necropsied and when tularemia is suspected culture and/or PCR are performed to confirm the diagnosis. The aim of this study was to present the results of tularemia surveillance in wildlife and to investigate the spatial and temporal pattern of tularemia observed between the 2002-2003 and 2012-2013 hunting seasons in French wildlife. Fourty-one to 121 cases were collected each hunting season for a total of 693 confirmed cases and 46 additional suspected cases. The main species affected was the European Brown Hare (Lepus europaeus) but 4 rabbits (Oryctolagus cuniculus), 2 roe deer (Capreolus capreolus) and one wild boar (Sus scrofa) were also found positive. The Standard Mortality Ratio was mapped and Kulldorff's retrospective space-time scan statistic was implemented and allowed the detection of several clusters: the nationwide outbreak of 2007-2008; 2 clusters in northern and central-western France in high hare-abundance areas and another in North-eastern France where the abundance of hares is low. Our results confirm the usefulness of brown hare as a sentinel of environmental risk. Copyright © 2016 Elsevier B.V. All rights reserved.

Is climate change affecting wolf populations in the high Arctic?

USGS Publications Warehouse

Mech, L.D.

2004-01-01

Global climate change may affect wolves in Canada's High Arctic (80DG N) acting through three trophic levels (vegetation, herbivores, and wolves). A wolf pack dependent on muskoxen and arctic hares in the Eureka area of Ellesmere Island denned and produced pups most years from at least 1986 through 1997. However when summer snow covered vegetation in 1997 and 2000 for the first time since records were kept, halving the herbivore nutrition-replenishment period, muskox and hare numbers dropped drastically, and the area stopped supporting denning wolves through 2003. The unusual weather triggering these events was consistent with global-climate-change phenomena.

Is climate change affecting wolf populations in the high Arctic?

USGS Publications Warehouse

Mech, L.D.

2004-01-01

Gobal climate change may affect wolves in Canada's High Arctic (80?? N) acting through three trophic levels (vegetation, herbivores, and wolves). A wolf pack dependent on muskoxen and arctic hares in the Eureka area of Ellesmere Island denned and produced pups most years from at least 1986 through 1997. However, when summer snow covered vegetation in 1997 and 2000 for the first time since records were kept, halving the herbivore nutrition-replenishment period, muskox and hare numbers dropped drastically, and the area stopped supporting denning wolves through 2003. The unusual weather triggering these events was consistent with global-climate-change phenomena. ?? 2004 Kluwer Academic Publishers.

Fatal toxoplasmosis in brown hares (Lepus europaeus): possible reasons of their high susceptibility to the infection.

PubMed

Sedlák, K; Literák, I; Faldyna, M; Toman, M; Benák, J

2000-11-01

Brown hares (Lepus europaeus) trapped in the countryside and domestic rabbits were experimentally infected with Toxoplasma gondii (K7 strain) oocysts. Hares (n=12) were divided into groups of 4 and infected with 10, 10(3) and 10(5) oocysts. Rabbits (n=12) were infected in the same way. The experimentally infected animals were monitored for 33 days after infection (p.i.). Most of the infected hares demonstrated behavioural changes, and all of them died between 8 and 19 days p.i. Three of the rabbits demonstrated only clinical changes related to the concurrent pasteurellosis. The typical pathological finding in the hares were haemorrhagic enteritis, enlargement and hyperaemia of mesenteric lymph nodes, splenomegaly and multiple miliary necrotic lesions in the parenchyma of the liver and other organs. Pathological changes in the rabbits were less pronounced than in the hares. In rabbit brains, tissue cysts of the T. gondii were found. The incidence of T. gondii antibodies both in the hares and the rabbits was first ascertained on day 7 p.i. On day 12 p.i., antibodies were already found in all the animals infected. Antibody titres in indirect fluorescence antibody test (IFAT) using the anti-rabbit conjugate were markedly higher in rabbits than in hares. In all hares, T. gondii was isolated post mortem from the liver, brain, spleen, kidney, lung, heart and skeletal muscles. Although T. gondii was also isolated in all rabbits, it was not always isolated in all their organs. In all hares, parasitemia was demonstrated on days 7 and 12 p.i. The percentage of rabbits with detected parasitemia was lower. In hares, a decrease in the numbers of leukocytes during the infection was observed. No such decrease was observed in the rabbits. The lymphocyte activity after the stimulation with non-specific mitogens showed significant differences between the hares and the rabbits even before the infection. After the infection, the hares infected with 10(3) and 10(5) doses and in rabbits infected with a 10(5) dose showed a decrease of lymphocyte activity. Rabbits infected with a 10(3) dose showed an increase of the lymphocyte activity. While in hares toxoplasmosis was an acute and fatal disease, the infection in rabbits had subclinical manifestations only and easily passed to a latent stage. The different courses of toxoplasmosis in the hare and the rabbit may be due to the differences in the natural sensitivity of the two species to the T. gondii infection or a negative impact of stress to the immune status of hares.

First evidence of Leishmania infection in European brown hare (Lepus europaeus) in Greece: GIS analysis and phylogenetic position within the Leishmania spp.

PubMed

Tsokana, C N; Sokos, C; Giannakopoulos, A; Mamuris, Z; Birtsas, P; Papaspyropoulos, K; Valiakos, G; Spyrou, V; Lefkaditis, M; Chatzopoulos, D C; Kantere, M; Manolakou, K; Touloudi, A; Burriel, A Rodi; Ferroglio, E; Hadjichristodoulou, C; Billinis, C

2016-01-01

Although the existence of a sylvatic transmission cycle of Leishmania spp., independent from the domestic cycle, has been proposed, data are scarce on Leishmania infection in wild mammals in Greece. In this study, we aimed to investigate the presence of Leishmania infection in the European brown hare in Greece, to infer the phylogenetic position of the Leishmania parasites detected in hares in Greece, and to identify any possible correlation between Leishmania infection in hares with environmental parameters, using the geographical information system (GIS). Spleen samples from 166 hares were tested by internal transcribed spacer-1 (ITS-1)-nested PCR for the detection of Leishmania DNA. Phylogenetic analysis was performed on Leishmania sequences from hares in Greece in conjunction with Leishmania sequences from dogs in Greece and 46 Leishmania sequences retrieved from GenBank. The Leishmania DNA prevalence in hares was found to be 23.49 % (95 % confidence interval (CI) 17.27-30.69). The phylogenetic analysis confirmed that the Leishmania sequences from hares in Greece belong in the Leishmania donovani complex. The widespread Leishmania infection in hares should be taken into consideration because under specific circumstances, this species can act as a reservoir host. This study suggests that the role of wild animals, including hares, in the epidemiology of Leishmania spp. in Greece deserves further elucidation.

Reproductive characteristics of migratory golden eagles in Denali National Park, Alaska

USGS Publications Warehouse

McIntyre, Carol L.; Adams, Layne G.

1999-01-01

We describe reproductive characteristics of Golden Eagles (Aquila chrysaetos) breeding in Denali National Park, Alaska during an entire snowshoe hare (Lepus americanus) cycle, 1988-1997. Data on nesting eagles were collected at 58 to 72 nesting areas annually using two aerial surveys. Surveys were conducted during the incubation period to determine occupancy and nesting activities and late in the nestling period to count nestlings and determine nesting success. Annual occupancy rates of nesting areas did not vary significantly, whereas laying rates, success rates, and mean brood size varied significantly over the study period. Fledgling production for the study population varied sevenfold during the ten-year period. Laying rates, mean brood size, and overall population productivity were significantly correlated with abundance of cyclic snowshoe hare and Willow Ptarmigan (Lugopus lagopus) populations. Reproductive rates of Golden Eagles in Denali were similar to those of Golden Eagles from other high latitude study areas in North America, but lower than for Golden Eagles from temperate zone study areas in North America.

High fitness costs of climate change-induced camouflage mismatch.

PubMed

Zimova, Marketa; Mills, L Scott; Nowak, J Joshua

2016-03-01

Anthropogenic climate change has created myriad stressors that threaten to cause local extinctions if wild populations fail to adapt to novel conditions. We studied individual and population-level fitness costs of a climate change-induced stressor: camouflage mismatch in seasonally colour molting species confronting decreasing snow cover duration. Based on field measurements of radiocollared snowshoe hares, we found strong selection on coat colour molt phenology, such that animals mismatched with the colour of their background experienced weekly survival decreases up to 7%. In the absence of adaptive response, we show that these mortality costs would result in strong population-level declines by the end of the century. However, natural selection acting on wide individual variation in molt phenology might enable evolutionary adaptation to camouflage mismatch. We conclude that evolutionary rescue will be critical for hares and other colour molting species to keep up with climate change. © 2016 The Authors. Ecology Letters published by CNRS and John Wiley & Sons Ltd.

Hares promote seed dispersal and seedling establishment after volcanic eruptions

NASA Astrophysics Data System (ADS)

Nomura, Nanae; Tsuyuzaki, Shiro

2015-02-01

Although seed dispersal through animal guts (endozoochory) is a process that determines plant establishment, the behaviour of carriers mean that the seeds are not always dispersed to suitable habitats for germination. The germinable seeds of Gaultheria miqueliana were stored in the pellets of a hare (Lepus timidus ainu) on Mount Koma in northern Japan. To clarify the roles of hares in seed dispersal and germination, field censuses and laboratory experiments were conducted. The field observations were conducted on pellets and seeds in four habitats (bare ground, G. miqueliana shrub patch, Salix reinii patch, and Larix kaempferi understory), and the laboratory experiments were conducted on seed germination with different light, water potential and cold stratification treatments. The laboratory experiments confirmed that seed germination began a few weeks after the sowing of seeds, independent of cold stratification, when light was sufficient and the water potential was low. The seeds did not germinate at high water potential. The pellets were gradually degraded in situ. More seeds germinated from crushed than from intact pellets. Therefore, over the long term, seeds germinated when exposed to light due to the degradation of pellets. The pellets were proportionally dispersed among the four studied habitats. More seeds sown in the field germinated more in shaded habitats, such as in the Gaultheria patch and the Larix understory, and seeds did not germinate on bare ground, where drought often occurred. Thus, the hares had two roles in the dispersal and germination of seeds: (1) the expansion of G. miqueliana populations through seed dispersal to various habitats and (2) the facilitation of delayed seed germination to avoid risks of hazards such as drought. The relationships between small mammals represented by the hare and the shrubs that produce berries are likely to be more mutually evolved than was previously thought.

Non-territorial floaters in Great Horned Owls (Bubo virginianus)

Treesearch

Christoph Rohner

1997-01-01

The ecology and behavior of non-territorial owls are basically unknown. I studied the integration of young Great Horned Owls (Bubo virginianus) into the territorial breeding population from 1988-1993 in the southwestern Yukon, Canada, during a peak and decline of the population cycle of snowshoe hares (Lepus americanus). Fifty-five...

Parasites of domestic and wild animals in South Africa. XXXII. Ixodid ticks on scrub hares in the Transvaal.

PubMed

Horak, I G; Spickett, A M; Braack, L E; Penzhorn, B L

1993-09-01

A total of 264 scrub hares (Lepus saxatilis) were examined for ixodid ticks at various localities in the Kruger National Park, eastern Transvaal Lowveld. Thirteen tick species were recovered from these hares. The seasonal abundances of the immature stages of Amblyomma hebraeum, Amblyomma marmoreum, Hyalomma truncatum, Rhipicephalus appendiculatus, Rhipicephalus evertsi evertsi, Rhipicephalus simus and Rhipicephalus zambeziensis and all stages of a Rhipicephalus sp. (near R. pravus) were determined. Three scrub hares, examined in the north-western Transvaal Bushveld, were infested with five ixodid tick species. Ten hares examined in the eastern Transvaal Highveld harboured three species. A total of 15 ixodid tick species were recovered from the scrub hares examined in the three regions of the Transvaal. No haematozoa were found in blood smears made from the hares examined in the southern region of the Kruger National Park.

The ligand-binding profile of HARE: hyaluronan and chondroitin sulfates A, C, and D bind to overlapping sites distinct from the sites for heparin, acetylated low-density lipoprotein, dermatan sulfate, and CS-E.

PubMed

Harris, Edward N; Weigel, Paul H

2008-08-01

The hyaluronic acid receptor for endocytosis (HARE)/ Stabilin-2 is the primary systemic scavenger receptor for hyaluronan (HA), the chondroitin sulfates (CS), dermatan sulfate (DS), and nonglycosaminoglycan (GAG) ligands such as acetylated low-density lipoprotein (AcLDL), pro-collagen propeptides, and advanced glycation end products. We recently discovered that HARE is also a systemic scavenger receptor for heparin (Hep) (Harris EN, Weigel JA, Weigel PH. 2008. The human hyaluronan receptor for endocytosis [HARE/Stabilin-2] is a systemic clearance receptor for heparin. J Biol Chem. 283:17341-17350). Our goal was to map the binding sites of eight different ligands within HARE. We used biotinylated GAGs and radio-iodinated streptavidin or AcLDL to assess the binding activities of ligands directly or indirectly (by competition with unlabeled ligands) in endocytosis assays using stable cell lines expressing the 315 or 190 kDa HA receptor for endocytosis (315- or 190-HARE) isoforms, and ELISA-like assays, with purified recombinant soluble 190-HARE ecto-domain. For example, Hep binding to HARE was competed by DS, CS-E, AcLDL, and dextran sulfate, but not by other CS types, HA, dextran, or heparosan. (125)I-AcLDL binding to HARE was partially competed by Hep and dextran sulfate, but not competed by HA. Two ligands, DS and CS-E, competed with both Hep and HA to some degree. Hep and HA binding or endocytosis is mutually inclusive; binding of these two GAGs occurs with functionally separate, noncompetitive, and apparently noninteracting domains. Thus, HARE binds to HA and Hep simultaneously. Although the domain(s) responsible for Hep binding remains unknown, the Link domain was required for HARE binding to HA, CS-A, CS-C, and CS-D. These results enable us to outline, for the first time, a binding activity map for multiple ligands of HARE.

The ligand-binding profile of HARE: hyaluronan and chondroitin sulfates A, C, and D bind to overlapping sites distinct from the sites for heparin, acetylated low-density lipoprotein, dermatan sulfate, and CS-E

PubMed Central

Harris, Edward N.; Weigel, Paul H.

2008-01-01

The hyaluronic acid receptor for endocytosis (HARE)/ Stabilin-2 is the primary systemic scavenger receptor for hyaluronan (HA), the chondroitin sulfates (CS), dermatan sulfate (DS), and nonglycosaminoglycan (GAG) ligands such as acetylated low-density lipoprotein (AcLDL), pro-collagen propeptides, and advanced glycation end products. We recently discovered that HARE is also a systemic scavenger receptor for heparin (Hep) (Harris EN, Weigel JA, Weigel PH. 2008. The human hyaluronan receptor for endocytosis [HARE/Stabilin-2] is a systemic clearance receptor for heparin. J Biol Chem. 283:17341–17350). Our goal was to map the binding sites of eight different ligands within HARE. We used biotinylated GAGs and radio-iodinated streptavidin or AcLDL to assess the binding activities of ligands directly or indirectly (by competition with unlabeled ligands) in endocytosis assays using stable cell lines expressing the 315 or 190 kDa HA receptor for endocytosis (315- or 190-HARE) isoforms, and ELISA-like assays, with purified recombinant soluble 190-HARE ecto-domain. For example, Hep binding to HARE was competed by DS, CS-E, AcLDL, and dextran sulfate, but not by other CS types, HA, dextran, or heparosan. 125I-AcLDL binding to HARE was partially competed by Hep and dextran sulfate, but not competed by HA. Two ligands, DS and CS-E, competed with both Hep and HA to some degree. Hep and HA binding or endocytosis is mutually inclusive; binding of these two GAGs occurs with functionally separate, noncompetitive, and apparently noninteracting domains. Thus, HARE binds to HA and Hep simultaneously. Although the domain(s) responsible for Hep binding remains unknown, the Link domain was required for HARE binding to HA, CS-A, CS-C, and CS-D. These results enable us to outline, for the first time, a binding activity map for multiple ligands of HARE. PMID:18499864

The European Hare (Lepus europaeus): A Picky Herbivore Searching for Plant Parts Rich in Fat

PubMed Central

Schai-Braun, Stéphanie C.; Reichlin, Thomas S.; Ruf, Thomas; Klansek, Erich; Tataruch, Frieda; Arnold, Walter; Hackländer, Klaus

2015-01-01

European hares of both sexes rely on fat reserves, particularly during the reproduc-tive season. Therefore, hares should select dietary plants rich in fat and energy. However, hares also require essential polyunsaturated fatty acids (PUFA) such as linoleic acid (LA) and alpha-linolenic acid (ALA) to reproduce and survive. Although hares are able to absorb PUFA selectively in their gastrointestinal tract, it is unknown whether this mechanism is sufficient to guarantee PUFA supply. Thus, diet selection may involve a trade-off between a preference for energy versus a preference for crucial nutrients, namely PUFA. We compared plant and nutrient availability and use by hares in an arable landscape in Austria over three years. We found that European hares selected their diet for high energy content (crude fat and crude protein), and avoided crude fibre. There was no evidence of a preference for plants rich in LA and ALA. We conclude that fat is the limiting resource for this herbivorous mammal, whereas levels of LA and ALA in forage are sufficiently high to meet daily requirements, especially since their uptake is enhanced by physiological mechanisms. Animals selected several plant taxa all year round, and preferences did not simply correlate with crude fat content. Hence, European hares might not only select for plant taxa rich in fat, but also for high-fat parts of preferred plant taxa. As hares preferred weeds/grasses and various crop types while avoiding cereals, we suggest that promoting heterogeneous habitats with high crop diversity and set-asides may help stop the decline of European hares throughout Europe. PMID:26230115

Swimming performance and unique wake topology of the sea hare (Aplysia)

NASA Astrophysics Data System (ADS)

Zhou, Zhuoyu; Mittal, Rajat

2018-03-01

The Aplysia, commonly referred to as the "sea hare," is a marine mollusc that swims using large-amplitude flapping of its wide, winglike parapodia. In this study, flow simulations with a relatively simple kinematical model are used to gain insights into the vortex dynamics, thrust generation, and energetics of locomotion for this animal. A unique vortex pattern characterized by three distinct trains of vortex ringlike structures is observed in the wake of this animal. These vortex rings are associated with a positive momentum flux in the wake that counteracts the drag generated by the body. Simulations indicate propulsive efficiencies of up to 24% and terminal swimming speeds of about 0.9 body length per cycle. Swimming speeds are found to increase with increasing parapodial flapping amplitude as well as wavelength of undulation.

Evidence for range contraction of snowshoe hare in Pennsylvania

USGS Publications Warehouse

Diefenbach, Duane R.; Rathbun, Stephen L.; Vreeland, J.K.; Grove, Deborah; Kanapaux, William J.

2016-01-01

In Pennsylvania, Lepus americanus (Snowshoe Hare) is near the southern limits of its range and at risk of range contraction because of loss of early-successional forest and impacts of climate change. We used hunter-harvest data to investigate changes in the distribution of Snowshoe Hare in Pennsylvania (1983–2011), forest inventory and land-use data to assess changes in amount and distribution of early-successional forest (1988–2011), and occupancy modeling (2004) to identify habitat and climate variables that explain the current distribution of Snowshoe Hare. We determined presence of Snowshoe Hare based on visual sightings, observations of tracks, and DNA analysis of fecal pellets, and used repeated visits to sampling sites and occupancy models to estimate occupancy rates (Ψ). Hunter-harvest data indicated the range of Snowshoe Hare in Pennsylvania contracted towards northwestern and northeastern portions of the state. Based on occupancy modeling, Snowshoe Hare were most likely to occupy early-successional and mixed deciduous-coniferous forest types and areas with colder winter temperatures, which coincided with the distribution of hunter harvests. Among the 4 forest types, we estimated Ψ = 0.52-0.79 and Ψ = 0.10-0.32 where winter temperatures were coldest and warmest, respectively. Total forest loss was <1% during 1988-2011, and the loss of early-successional forest in the current and former range of Snowshoe Hares was similar as were mean patch size and a fragmentation metric of early-successional habitat. Thus, changes in forest characteristics did not explain the range contraction we observed. We used climate-model predictions and our occupancy model to predict that average occupancy probability across northern Pennsylvania may decline from 0.27 in 2004 to 0.10–0.18 by 2050–2059, depending on the climate model. The range of Snowshoe Hare in Pennsylvania has contracted to regions of Pennsylvania with the coldest winter temperatures and most persistent snowpack, and based on projected climate change, our results suggest further range contraction of Snowshoe Hare in Pennsylvania.

Identification of hare meat by a species-specific marker of mitochondrial origin.

PubMed

Santos, Cristina G; Melo, Vitor S; Amaral, Joana S; Estevinho, Letícia; Oliveira, M Beatriz P P; Mafra, Isabel

2012-03-01

Meat species identification in food has gained increasing interest in recent years due to public health, economic and legal concerns. Following the consumer trend towards high quality products, game meat has earned much attention. The aim of the present work was to develop a DNA-based technique able to identify hare meat. Mitochondrial cytochrome b gene was used to design species-specific primers for hare detection. The new primers proved to be highly specific to Lepus species, allowing the detection of 0.01% of hare meat in pork meat by polymerase chain reaction (PCR). A real-time PCR assay with the new intercalating EvaGreen dye was further proposed as a specific and fast tool for hare identification with increased sensitivity (1pg) compared to end-point PCR (10pg). It can be concluded that the proposed new primers can be used by both species-specific end-point PCR or real-time PCR to accurately authenticate hare meat. Copyright © 2011 Elsevier Ltd. All rights reserved.

Improving the assessment of predator functional responses by considering alternate prey and predator interactions.

PubMed

Chan, K; Boutin, S; Hossie, T J; Krebs, C J; O'Donoghue, M; Murray, D L

2017-07-01

To improve understanding of the complex and variable patterns of predator foraging behavior in natural systems, it is critical to determine how density-dependent predation and predator hunting success are mediated by alternate prey or predator interference. Despite considerable theory and debate seeking to place predator-prey interactions in a more realistic context, few empirical studies have quantified the role of alternate prey or intraspecific interactions on predator-prey dynamics. We assessed functional responses of two similarly sized, sympatric carnivores, lynx (Lynx canadensis) and coyotes (Canis latrans), foraging on common primary (snowshoe hares; Lepus americanus) and alternate (red squirrels; Tamiasciurus hudsonicus) prey in a natural system. Lynx exhibited a hyperbolic prey-dependent response to changes in hare density, which is characteristic of predators relying primarily on a single prey species. In contrast, the lynx-squirrel response was found to be linear ratio dependent, or inversely dependent on hare density. The coyote-hare and coyote-squirrel interactions also were linear and influenced by predator density. We explain these novel results by apparent use of spatial and temporal refuges by prey, and the likelihood that predators commonly experience interference and lack of satiation when foraging. Our study provides empirical support from a natural predator-prey system that (1) predation rate may not be limited at high prey densities when prey are small or rarely captured; (2) interference competition may influence the predator functional response; and (3) predator interference has a variable role across different prey types. Ultimately, distinct functional responses of predators to different prey types illustrates the complexity associated with predator-prey interactions in natural systems and highlights the need to investigate predator behavior and predation rate in relation to the broader ecological community. © 2017 by the Ecological Society of America.

Vertebrate Herbivore Browsing on Neighboring Forage Species Increases the Growth and Dominance of Siberian Alder Across a Latitudinal Transect in Northern Alaska.

NASA Astrophysics Data System (ADS)

McNeill, E. M.; Ruess, R. W.

2017-12-01

Vertebrate herbivores strongly influence plant growth and architecture, biogeochemical cycling, and successional dynamics in boreal and arctic ecosystems. One of the most notable impacts of vertebrate herbivory is on the growth and spread of alder, a chemically-defended, N-fixing shrub whose distribution in the Alaskan arctic has expanded dramatically over the past 60 years. Although herbivore effects on thin-leaf alder are well described for interior Alaskan floodplains, no work has been conducted on the effects of herbivores on Siberian alder (Alnus viridis spp fruticosa), despite the increasing importance of this species to high latitude ecosystems. We characterized browsing by snowshoe hares, moose, and willow ptarmigan on dominant shrub species across topo-edaphic sequences within 5 ecoregions along a 600 km latitudinal transect extending from interior Alaska to the North Slope. Ptarmigan browsed wind-blown lowland and alpine sites devoid of trees in all regions; moose browsed predominantly willow species in hardwood and mixed forests and were absent north of the Brooks Range; snowshoe hares selected habitats and forage based on their local density and vulnerability to predators. Browsing intensity on Siberian alder was either undetectable or low, limited primarily to hare browsing on young ramets in the northern boreal forest where hare density relative to forage availability is highest. Overall, alder height growth was positively correlated with levels of herbivory on competing shrub species. Our data support the hypothesis that vertebrate herbivore browsing is indirectly augmenting the growth, dominance, and possible spread of Siberian alder throughout its northern Alaskan range. Given the potential high rates of N-fixation inputs by Siberian alder, we believe herbivores are also having strong indirect effects on biogeochemical cycling and possibly C storage in these landscapes.

Diets of black-tailed hares on the Hanford Reservation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Uresk, D.W.; Cline, J.F.; Rickard, W.H.

1975-04-01

A fecal pellet analyses showed that black-tailed hares (jackrabbits) were selective in plants chosen as food. The most abundant herbaceous plant, cheatgrass, was not found in the pellets. Sagebrush and bitterbrush, woody plants, were not an important part of the hares' diet. Forbs, rabbitbrush, and certain grass species were preferred foods. (auth)

Haring-Inspired Designs

ERIC Educational Resources Information Center

Corfield, Marie

2007-01-01

While exploring Keith Haring's Web site one day, the author discovered two untitled pieces from 1982 that became inspiration pieces for a lesson on symmetry and complementary colors for her second graders. Haring's simple shapes and colors and playful images are very similar to those found in the margins or on the cover of any typical child's…

Does Psychopathy Predict Institutional Misconduct among Adults?: A Meta-Analytic Investigation

ERIC Educational Resources Information Center

Guy, Laura S.; Edens, John F.; Anthony, Christine; Douglas, Kevin S.

2005-01-01

Narrative reviews have raised several questions regarding the predictive validity of the Hare Psychopathy Checklist-Revised (PCL-R; R. D. Hare, 2003) and related scales in institutional settings. In this meta-analysis, the authors coded 273 effect sizes to investigate the association between the Hare scales and a hierarchy of increasingly specific…

Robert Hare's Theory of Galvanism: A Study of Heat and Electricity in Early Nineteenth-Century American Chemistry.

PubMed

Fisher, Amy

2018-04-09

As a professor of chemistry at the University of Pennsylvania, Robert Hare actively shaped early American science. He participated in a large network of scholars, including Joseph Henry, François Arago, and Jacob Berzelius, and experimented with and wrote extensively about electricity and its associated chemical and thermal phenomena. In the early nineteenth century, prominent chemists such as Berzelius and Humphry Davy proclaimed that a revolution had occurred in chemistry through electrical research. Examining Robert Hare's contributions to this discourse, this paper analyzes how Hare's study of electricity and the caloric theory of heat led him to propose a new theory of galvanism. It also examines the reception of Hare's work in America and Great Britain, highlighting the contributions of early American chemists to the development of electrochemistry.

Influence of forest structure on the abundance of snowshoe hares in western Wyoming

Treesearch

Nathan D. Berg; Eric M. Gese; John R. Squires; Lise M. Aubry

2012-01-01

Snowshoe hares (Lepus americanus) are a primary prey species for Canada lynx (Lynx canadensis) in western North America. Lynx management plans require knowledge of potential prey distribution and abundance in the western United States. Whether even-aged regenerating forests or multi-storied forests contain more snowshoe hares is currently unknown. During 2006-...

Activity patterns of American martens, fishers, snowshoe hares, and red squirrels in westcentral Montana

Treesearch

Kerry R. Foresman; Dean Pearson

1999-01-01

We investigated winter activity patterns of American Martens, Martes americana, Snowshoe Hares, Lepus americanus, and Red Squirrels, Tamiasciurus hudsonicus, in westcentral Montana between November 1994 and March 1995 using dual-sensor remote cameras. One hundred percent of Snowshoe Hare (n = 25) observations occurred at night while Martens (n = 85) exhibited...

Top predators, mesopredators and their prey: interference ecosystems along bioclimatic productivity gradients.

PubMed

Elmhagen, B; Ludwig, G; Rushton, S P; Helle, P; Lindén, H

2010-07-01

1. The Mesopredator Release Hypothesis (MRH) suggests that top predator suppression of mesopredators is a key ecosystem function with cascading impacts on herbivore prey, but it remains to be shown that this top-down cascade impacts the large-scale structure of ecosystems. 2. The Exploitation Ecosystems Hypothesis (EEH) predicts that regional ecosystem structures are determined by top-down exploitation and bottom-up productivity. In contrast to MRH, EEH assumes that interference among predators has a negligible impact on the structure of ecosystems with three trophic levels. 3. We use the recolonization of a top predator in a three-level boreal ecosystem as a natural experiment to test if large-scale biomass distributions and population trends support MRH. Inspired by EEH, we also test if top-down interference and bottom-up productivity impact regional ecosystem structures. 4. We use data from the Finnish Wildlife Triangle Scheme which has monitored top predator (lynx, Lynx lynx), mesopredator (red fox, Vulpes vulpes) and prey (mountain hare, Lepus timidus) abundance for 17 years in a 200 000 km(2) study area which covers a distinct productivity gradient. 5. Fox biomass was lower than expected from productivity where lynx biomass was high, whilst hare biomass was lower than expected from productivity where fox biomass was high. Hence, where interference controlled fox abundance, lynx had an indirect positive impact on hare abundance as predicted by MRH. The rates of change indicated that lynx expansion gradually suppressed fox biomass. 6. Lynx status caused shifts between ecosystem structures. In the 'interference ecosystem', lynx and hare biomass increased with productivity whilst fox biomass did not. In the 'mesopredator release ecosystem', fox biomass increased with productivity but hare biomass did not. Thus, biomass controlled top-down did not respond to changes in productivity. This fulfils a critical prediction of EEH. 7. We conclude that the cascade involving top predators, mesopredators and their prey can determine large-scale biomass distribution patterns and regional ecosystem structures. Hence, interference within trophic levels has to be taken into account to understand how terrestrial ecosystem structures are shaped.

Standardization of the Hare Psychopathy Checklist-Revised in a Spanish prison sample.

PubMed

Moltó, J; Poy, R; Torrubia, R

2000-01-01

This investigation examined the reliability, validity, and factor structure of the Hare Psychopathy Checklist-Revised (PCL-R) in male adult Spanish prison populations (n = 117). The interrater reliability and internal consistency coefficients were high, and similar to those obtained in other countries. This data provides support for the homogeneity and unidimensionality of the psychopathy construct in Spanish male prison samples. The analysis of factor structure also replicated the two factor solution of previous studies. The two factors showed different patterns of intercorrelations with several self-report measures of personality, demographic, and criminal history variables, which confirmed the construct validity of PCL-R. The results confirm the psychometric properties of the PCL-R as a measure of psychopathy in Spanish male inmates, and suggest that psychopathy is a construct also observed in Southern European countries.

Movements, activity patterns, and habitat use of snowshoe hares (Lepus americanus) in interior Alaska

Treesearch

D. Feierabend; K. Kielland

2014-01-01

Snowshoe hares (Lepus americanus) are generally sedentary, but are likely to move among habitats frequently to gain access to spatially segregated food and cover. We investigated movement patterns of hares from 2 characteristic boreal habitats using very-high-frequency radio collars (n ¼ 300) monitored weekly and global positioning system (GPS) collars (n ¼ 18)...

Characteristics of a new automatic hail recorder

NASA Astrophysics Data System (ADS)

Löffler-Mang, Martin; Schön, Dominik; Landry, Markus

2011-06-01

An automatic hail sensor was developed, based on signal production with microphones, a quick signal analysis and recording possibility. For this hail recorder (HARE) small piezo-electric microphones inside a Makrolon body are used to detect hailstones. The prototype has an octagonal shape, two microphones on the top and bottom plates situated in the middle of the device, and an electronic board. A hailstone striking the surface produces waves on the sensor body and a voltage in the piezo-electric microphones. Each hail event is stored in the internal memory including the time and date. The memory can be read out via a USB port at any time after one or more hail events. HARE was tested and calibrated with the help of a newly constructed pneumatic hail gun. The voltage signal at the top plate microphone of HARE increases linearly proportional to hailstone momentum, whereas at the bottom plate it increases linearly proportional to hailstone kinetic energy. For large hailstones the accuracy of HARE is in the order of 10%. Calibration of HARE is still in progress and it has not been tested in real hailfalls as yet. An online device as well as an autonomous one is available for a large number of possible applications. Lately there has been interest to use HARE at solar power plants in Southern Europe to prevent the expensive modules from becoming damaged. Perhaps HARE could also participate in new and existing hail observing networks.

On the selection of ordinary differential equation models with application to predator-prey dynamical models.

PubMed

Zhang, Xinyu; Cao, Jiguo; Carroll, Raymond J

2015-03-01

We consider model selection and estimation in a context where there are competing ordinary differential equation (ODE) models, and all the models are special cases of a "full" model. We propose a computationally inexpensive approach that employs statistical estimation of the full model, followed by a combination of a least squares approximation (LSA) and the adaptive Lasso. We show the resulting method, here called the LSA method, to be an (asymptotically) oracle model selection method. The finite sample performance of the proposed LSA method is investigated with Monte Carlo simulations, in which we examine the percentage of selecting true ODE models, the efficiency of the parameter estimation compared to simply using the full and true models, and coverage probabilities of the estimated confidence intervals for ODE parameters, all of which have satisfactory performances. Our method is also demonstrated by selecting the best predator-prey ODE to model a lynx and hare population dynamical system among some well-known and biologically interpretable ODE models. © 2014, The International Biometric Society.

One Measure Does Not a Construct Make: Directions toward Reinvigorating Psychopathy Research--Reply to Hare and Neumann (2010)

ERIC Educational Resources Information Center

Skeem, Jennifer L.; Cooke, David J.

2010-01-01

In our article (J. L. Skeem & D. J. Cooke, 2010), we outlined the dangers inherent in conflating the Psychopathy Checklist-Revised (PCL-R; R. Hare, 1991) with psychopathy itself. In their response, R. Hare and C. Neumann (2010) seemed to agree with key points that the PCL-R should not be confused with psychopathy and that criminal behavior is not…

An Inmate Classification System Based on PCL: SV Factor Scores in a Sample of Prison Inmates

ERIC Educational Resources Information Center

Wogan, Michael; Mackenzie, Marci

2007-01-01

Psychopaths represent a significant management challenge in a prison population. A sample of ninety-five male inmates from three medium security prisons was tested using the Hare Psychopathy Checklist: Screening Version (PCL:SV). Using traditional criteria, 22% of the inmates were classified as psychopaths. Scores on the two factor dimensions of…

Predicting the effects of forest management on lynx populations

Treesearch

John R. Squires

2008-01-01

Lynx are quintessential snowshoe hare predators with morphological adaptations such as large paws. This species depends on boreal forests, so the listing of Canada Lynx as a Threatened species is a major conservation issue to forest managers. The U.S. Fish and Wildlife Service stated that human alteration of forest abundance, composition, and connectivity was the most...

Black-flies and Leucocytozoon spp. as causes of mortality in juvenile Great Horned Owls in the Yukon, Canada

Treesearch

D. Bruce Hunter; Christoph Rohner; Doug C. Currie

1997-01-01

Black fly feeding and infection with the blood parasite Leucocytozoon spp. caused mortality in juvenile Great Horned Owls (Bubo virginianus) in the Yukon, Canada during 1989-1990. The mortality occurred during a year of food shortage corresponding with the crash in snowshoe hare (Lepus americanus) populations. We...

Tularaemia in European Brown Hares (Lepus europaeus) and Mountain Hares (Lepus timidus) Characterized by Histopathology and Immunohistochemistry: Organ Lesions and Suggestions of Routes of Infection and Shedding.

PubMed

Hestvik, G; Uhlhorn, H; Södersten, F; Åkerström, S; Karlsson, E; Westergren, E; Gavier-Widén, D

Tularaemia is an emerging zoonotic infectious disease caused by the bacterium Francisella tularensis. In Sweden, hares are considered to be key species in the epidemiology of tularaemia. The aim of this study was to characterize the pathology of natural tularaemia infection in European brown hares (EBHs) (Lepus europaeus) and mountain hares (MHs) (Lepus timidus) in Sweden, in order to better understand the presentation of disease and the routes of infection, body dissemination and shedding of F. tularensis. During 2000-2013, 49 EBHs and 37 MHs were diagnosed with tularaemia. Enlargement of the spleen was seen in 80% of EBHs and 62% of MHs. Necrosis was often obvious in the bone marrow, liver, lung and spleen, but 30% of the hares had no lesions or minimal gross lesions. On microscopical examination of tissues from 27 EBHs and three MHs, necrosis was seen in the majority of samples of liver, spleen, bone marrow, lymph node and adrenal glands and was common in the lungs and brain meninges. Immunohistochemistry for Francisella spp. detected bacteria in association with necrosis and inflammation. In several cases, Francisella spp. were also found inside blood vessels, in the renal pelvis, in lactating mammary glands, in bronchioles and in the skin, associated with tick bites. Using quantitative polymerase chain reaction, two genotypes of F. tularensis subsp. holarctica were found; canSNP group B.6, all belonging to subgroup B.7, and canSNP group B.12. There were no differences in pathology between the genotypes. Our results indicate that the urinary tract and mammary glands are important routes for the shedding of F. tularensis. Hunters may not be aware of the risks of contracting tularaemia while handling hares, since infected hares do not always show noticeable gross lesions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Hepatitis E virus in wild rabbits and European brown hares in Germany.

PubMed

Hammerschmidt, F; Schwaiger, K; Dähnert, L; Vina-Rodriguez, A; Höper, D; Gareis, M; Groschup, M H; Eiden, M

2017-12-01

Recently, a change of hepatitis E from being a typical travel-associated disease to an autochthonous zoonosis in Germany was observed. An increasing number of autochthonous infections with the hepatitis E Virus (HEV) have been recognized in developed countries. Venison from wild boar is already known to be a potential source of infection, if not prepared properly by the consumer. In Germany, certain wild animals are known to be a reservoir for HEV. However, current information is missing about European brown hares (Lepus europaeus) and wild rabbits (Oryctolagus cuniculus). Thus, a total of 833 hunting-harvested animals (European brown hares n = 669; wild rabbits n = 164) were tested for the occurrence of HEV RNA and HEV antibodies. For this, liver and blood specimens were taken after hunts in six German federal states. HEV antibodies were found by ELISA in 2.2% (624/14) of European brown hares, but no HEV RNA was detectable by nested real-time RT-PCR. In contrast, a seroprevalence of 37.3% (126/47) was observed for wild rabbits, and 17.1% (164/28) of the samples were HEV RNA positive. Genomic analysis revealed that these partial sequences clustered within the rabbit clade of HEV-3 genotype. In addition, one rabbit sequence segregated into subtype 3g of HEV-3. Highest seroprevalences for hares and rabbits were detected in the federal states of Bavaria and of Schleswig-Holstein, respectively. Comparing urban, rural and insular areas, the highest seroprevalence was shown for wild rabbits in rural areas and for European brown hares on the northern island Fehmarn. This study provides evidence that European brown hares and wild rabbits from Germany can be infected with HEV. The different prevalences indicate that wild rabbits are a potential reservoir for HEV in Germany, whereas European brown hares seem to be only of minor importance for the epidemiology of HEV. © 2017 Blackwell Verlag GmbH.

Psychopathy in Bulgaria: The cross-cultural generalizability of the Hare Psychopathy Checklist

PubMed Central

Wilson, Michael J.; Abramowitz, Carolyn; Vasilev, Georgi; Bozgunov, Kiril; Vassileva, Jasmin

2014-01-01

The generalizability of the psychopathy construct to Eastern European cultures has not been well-studied, and no prior studies have evaluated psychopathy in non-offender samples from this population. The current validation study examines the factor structure, internal consistency, and external validity of the Bulgarian translation of the Hare Psychopathy Checklist: Screening Version. Two hundred sixty-two Bulgarian adults from the general community were assessed, of which 185 had a history of substance dependence. Confirmatory factor analysis indicated good fit for the two-, three-, and four-factor models of psychopathy. Zero-order and partial correlation analyses were conducted between the two factors of psychopathy and criterion measures of antisocial behavior, internalizing and externalizing psychopathology, personality traits, addictive disorders and demographic characteristics. Relationships to external variables provided evidence for the convergent and discriminant validity of the psychopathy construct in a Bulgarian community sample. PMID:25313268

Multi-scale habitat relationships of snowshoe hares (Lepus americanus) in the mixed conifer landscape of the Northern Rockies, USA: Cross-scale effects of horizontal cover with implications for forest management

Treesearch

Joseph D. Holbrook; John R. Squires; Lucretia E. Olson; Rick L. Lawrence; Shannon L. Savage

2016-01-01

Snowshoe hares (Lepus americanus) are an ecologically important herbivore because they modify vegetation through browsing and serve as a prey resource for multiple predators. We implemented a multiscale approach to characterize habitat relationships for snowshoe hares across the mixed conifer landscape of the northern Rocky Mountains, USA. Our objectives were to (1)...

Tick infestation on sheep, goat, horse and wild hare in Tamil Nadu.

PubMed

Soundararajan, C; Nagarajan, K; Muthukrishnan, S; Arul Prakash, M

2018-03-01

The prevalence of tick infestation and their predilection sites on sheep, goat, horse and wild hare were studied at various places of Tamil Nadu, India. The prevalence of tick infestation in Madras red sheep, Tellicherry goat and horse was 77.11, 78.21 and 13.33%, respectively. Sheep were heavily infested with Haemaphysalis bispinosa followed by Hyalomma isaaci , Rhipicephalus haemaphysaloides and H . anatolicum . The ticks from goats were identified as H . bispinosa , R . haemaphysaloides , H . isaaci and R . sanguineus . Horses were infested with Otobus megnini and R . sanguineus . The ticks on wild hare ( Lepus nigricollis ) were identified as R . haemaphysaloides and H . bispinosa . Wild hare acts as a source of infestation to the sheep and goats since these animals shared the same field.

Mitochondrial and nuclear DNA reveals reticulate evolution in hares (Lepus spp., Lagomorpha, Mammalia) from Ethiopia

PubMed Central

Bekele, Endashaw; Tesfaye, Kassahun; Ben Slimen, Hichem; Valqui, Juan; Getahun, Abebe; Hartl, Günther B.; Suchentrunk, Franz

2017-01-01

For hares (Lepus spp., Leporidae, Lagomorpha, Mammalia) from Ethiopia no conclusive molecular phylogenetic data are available. To provide a first molecular phylogenetic model for the Abyssinian Hare (Lepus habessinicus), the Ethiopian Hare (L. fagani), and the Ethiopian Highland Hare (L. starcki) and their evolutionary relationships to hares from Africa, Eurasia, and North America, we phylogenetically analysed mitochondrial ATPase subunit 6 (ATP6; n = 153 / 416bp) and nuclear transferrin (TF; n = 155 / 434bp) sequences of phenotypically determined individuals. For the hares from Ethiopia, genotype composition at twelve microsatellite loci (n = 107) was used to explore both interspecific gene pool separation and levels of current hybridization, as has been observed in some other Lepus species. For phylogenetic analyses ATP6 and TF sequences of Lepus species from South and North Africa (L. capensis, L. saxatilis), the Anatolian peninsula and Europe (L. europaeus, L. timidus) were also produced and additional TF sequences of 18 Lepus species retrieved from GenBank were included as well. Median joining networks, neighbour joining, maximum likelihood analyses, as well as Bayesian inference resulted in similar models of evolution of the three species from Ethiopia for the ATP6 and TF sequences, respectively. The Ethiopian species are, however, not monophyletic, with signatures of contemporary uni- and bidirectional mitochondrial introgression and/ or shared ancestral polymorphism. Lepus habessinicus carries mtDNA distinct from South African L. capensis and North African L. capensis sensu lato; that finding is not in line with earlier suggestions of its conspecificity with L. capensis. Lepus starcki has mtDNA distinct from L. capensis and L. europaeus, which is not in line with earlier suggestions to include it either in L. capensis or L. europaeus. Lepus fagani shares mitochondrial haplotypes with the other two species from Ethiopia, despite its distinct phenotypic and microsatellite differences; moreover, it is not represented by a species-specific mitochondrial haplogroup, suggesting considerable mitochondrial capture by the other species from Ethiopia or species from other parts of Africa. Both mitochondrial and nuclear sequences indicate close phylogenetic relationships among all three Lepus species from Ethiopia, with L. fagani being surprisingly tightly connected to L. habessinicus. TF sequences suggest close evolutionary relationships between the three Ethiopian species and Cape hares from South and North Africa; they further suggest that hares from Ethiopia hold a position ancestral to many Eurasian and North American species. PMID:28767659

The Unique Propulsive Wake Pattern of the Swimming Sea Slug Aplysia

NASA Astrophysics Data System (ADS)

Zhou, Zhuoyu; Mittal, Rajat

2017-11-01

The Aplysia, also sometimes referred to as the `Sea Hare,' is a sea slug that swims elegantly using large-amplitude flapping of its mantle. The Sea Hare has become a very valuable laboratory animal for investigation into nervous systems and brain behavior due to its simple neural system with large neurons and axons. Recently, attempts have also been made to develop biohybrid robots with both organic actuation and organic motor-pattern control inspired by the locomotion of Aplysia. While extensive works have been done to investigate this animal's neurobiology, relatively little is known about its propulsive mechanisms and swimming energetics. In this study, incompressible flow simulations with a simple kinematical model are used to gain insights into vortex dynamics, thrust generation and energetics of locomotion. The effect of mantle kinematics on the propulsive performance is examined, and simulations indicate a unique vortex wake pattern that is responsible for thrust generation. The research is supported by NSF Grant PLR-1246317 and NSF XSEDE Grant TG-CTS100002.

Phlebotomine sand fly survey in the focus of leishmaniasis in Madrid, Spain (2012-2014): seasonal dynamics, Leishmania infantum infection rates and blood meal preferences.

PubMed

González, Estela; Jiménez, Maribel; Hernández, Sonia; Martín-Martín, Inés; Molina, Ricardo

2017-08-01

An unusual increase of human leishmaniasis cases due to Leishmania infantum is occurring in an urban area of southwestern Madrid, Spain, since 2010. Entomological surveys have shown that Phlebotomus perniciosus is the only potential vector. Direct xenodiagnosis in hares (Lepus granatensis) and rabbits (Oryctolagus cuniculus) collected in the focus area proved that they can transmit parasites to colonized P. perniciosus. Isolates were characterized as L. infantum. The aim of the present work was to conduct a comprehensive study of sand flies in the outbreak area, with special emphasis on P. perniciosus. Entomological surveys were done from June to October 2012-2014 in 4 stations located close to the affected area. Twenty sticky traps (ST) and two CDC light traps (LT) were monthly placed during two consecutive days in every station. LT were replaced every morning. Sand fly infection rates were determined by dissecting females collected with LT. Molecular procedures applied to study blood meal preferences and to detect L. infantum were performed for a better understanding of the epidemiology of the outbreak. A total of 45,127 specimens belonging to 4 sand fly species were collected: P. perniciosus (75.34%), Sergentomyia minuta (24.65%), Phlebotomus sergenti (0.005%) and Phlebotomus papatasi (0.005%). No Phlebotomus ariasi were captured. From 3203 P. perniciosus female dissected, 117 were infected with flagellates (3.7%). Furthermore, 13.31% and 7.78% of blood-fed and unfed female sand flies, respectively, were found infected with L. infantum by PCR. The highest rates of infected P. perniciosus were detected at the end of the transmission periods. Regarding to blood meal preferences, hares and rabbits were preferred, although human, cat and dog blood were also found. This entomological study highlights the exceptional nature of the Leishmania outbreak occurring in southwestern Madrid, Spain. It is confirmed that P. perniciosus is the only vector in the affected area, with high densities and infection rates. Rabbits and hares were the main blood meal sources of this species. These results reinforce the need for an extensive and permanent surveillance in this region, and others of similar characteristics, in order to control the vector and regulate the populations of wild reservoirs.

Snowshoe hares display limited phenotypic plasticity to mismatch in seasonal camouflage

USGS Publications Warehouse

Zimova, Marketa; Mills, L. Scott; Lukacs, Paul M.; Mitchell, Michael S.

2014-01-01

As duration of snow cover decreases owing to climate change, species undergoing seasonal colour moults can become colour mismatched with their background. The immediate adaptive solution to this mismatch is phenotypic plasticity, either in phenology of seasonal colour moults or in behaviours that reduce mismatch or its consequences. We observed nearly 200 snowshoe hares across a wide range of snow conditions and two study sites in Montana, USA, and found minimal plasticity in response to mismatch between coat colour and background. We found that moult phenology varied between study sites, likely due to differences in photoperiod and climate, but was largely fixed within study sites with only minimal plasticity to snow conditions during the spring white-to-brown moult. We also found no evidence that hares modify their behaviour in response to colour mismatch. Hiding and fleeing behaviours and resting spot preference of hares were more affected by variables related to season, site and concealment by vegetation, than by colour mismatch. We conclude that plasticity in moult phenology and behaviours in snowshoe hares is insufficient for adaptation to camouflage mismatch, suggesting that any future adaptation to climate change will require natural selection on moult phenology or behaviour.

Acidity enhances the effectiveness of active chemical defensive secretions of sea hares, Aplysia californica, against spiny lobsters, Panulirus interruptus.

PubMed

Shabani, Shkelzen; Yaldiz, Seymanur; Vu, Luan; Derby, Charles D

2007-12-01

Sea hares such as Aplysia californica, gastropod molluscs lacking a protective shell, can release a purple cloud of chemicals when vigorously attacked by predators. This active chemical defense is composed of two glandular secretions, ink and opaline, both of which contain an array of compounds. This secretion defends sea hares against predators such as California spiny lobsters Panulirus interruptus via multiple mechanisms, one of which is phagomimicry, in which secretions containing feeding chemicals attract and distract predators toward the secretion and away from the sea hare. We show here that ink and opaline are highly acidic, both having a pH of approximately 5. We examined if the acidity of ink and opaline affects their phagomimetic properties. We tested behavioral and electrophysiological responses of chemoreceptor neurons in the olfactory and gustatory organs of P. interruptus, to ink and opaline of A. californica within their natural range of pH values, from approximately 5 to 8. Both behavioral and electrophysiological responses to ink and opaline were enhanced at low pH, and low pH alone accounted for most of this effect. Our data suggest that acidity enhances the phagomimetic chemical defense of sea hares.

Powassan virus infection in snowshoe hares (Lepus americanus).

PubMed

Zarnke, R L; Yuill, T M

1981-04-01

Sera from snowshoe hares (Lepus americanus) trapped near Rochester, Alberta, Canada were tested for Powassan virus antibody by the constant virus/serum dilution neutralization test. Of 1264 serum samples tested, 137 had an antibody titer of at least 1:4 for Powassan virus. Ten hares were inoculated with Powassan virus in the laboratory. Viremia lasted 4-5 days and ceased with the appearance of Powassan antibody in the serum. Neutralizing antibody reached a peak titer of 1:119 on day 15 post-inoculation and was still detectable 13 months post-inoculation.

Tularaemia in a brown hare (Lepus europaeus) in 2013: first case in the Netherlands in 60 years.

PubMed

Rijks, J M; Kik, M; Koene, M G; Engelsma, M Y; van Tulden, P; Montizaan, M G; Oomen, T; Spierenburg, M A; Ijzer, J; van der Giessen, J W; Gröne, A; Roest, H J

2013-12-05

Tularaemia has not been reported in Dutch wildlife since 1953. To enhance detection, as of July 2011, brown hares (Lepus europaeus) submitted for postmortem examination in the context of non-targeted wildlife disease surveillance, were routinely tested for tularaemia by polymerase chain reaction (PCR). Francisella tularensis subspecies holarctica infection was confirmed in a hare submitted in May 2013. The case occurred in Limburg, near the site of the 1953 case. Further surveillance should clarify the significance of this finding.

Software Description for the O’Hare Runway Configuration Management System. Volume I. Technical Description,

DTIC Science & Technology

1982-10-01

spent in preparing this document. 00. EXECUTIVE SUMMARY The O’Hare Runway Configuration Management System (CMS) is an interactive multi-user computer ...MITRE Washington’s Computer Center. Currently, CMS is housed in an IBM 4341 computer with VM/SP operating system. CMS employs the IBM’s Display...iV 0O, o 0 .r4L /~ wA 0U 00 00 0 w vi O’Hare, it will operate on a dedicated mini- computer which permits multi-tasking (that is, multiple users

Effect of TCAS Interrogations on the Chicago O'Hare ATCRBS System

DOT National Transportation Integrated Search

1992-11-01

This report documents the Federal Aviation Administration (FAA) data collection : and analysis effort to investigate Secondary Surveillance Radar (SSR) problems : encountered at the Chicago O'Hare Terminal Approach Control (TRACON) facility. : The FA...

Environmental surveillance during an outbreak of tularaemia in hares, the Netherlands, 2015

PubMed Central

Janse, Ingmar; Maas, Miriam; Rijks, Jolianne M; Koene, Miriam; van der Plaats, Rozemarijn QJ; Engelsma, Marc; van der Tas, Peter; Braks, Marieta; Stroo, Arjan; Notermans, Daan W; de Vries, Maaike C; Reubsaet, Frans; Fanoy, Ewout; Swaan, Corien; Kik, Marja JL; IJzer, Jooske; Jaarsma, Ryanne I; van Wieren, Sip; de Roda-Husman, Ana Maria; van Passel, Mark; Roest, Hendrik-Jan; van der Giessen, Joke

2017-01-01

Tularaemia, a disease caused by the bacterium Francisella tularensis, is a re-emerging zoonosis in the Netherlands. After sporadic human and hare cases occurred in the period 2011 to 2014, a cluster of F. tularensis-infected hares was recognised in a region in the north of the Netherlands from February to May 2015. No human cases were identified, including after active case finding. Presence of F. tularensis was investigated in potential reservoirs and transmission routes, including common voles, arthropod vectors and surface waters. F. tularensis was not detected in common voles, mosquito larvae or adults, tabanids or ticks. However, the bacterium was detected in water and sediment samples collected in a limited geographical area where infected hares had also been found. These results demonstrate that water monitoring could provide valuable information regarding F. tularensis spread and persistence, and should be used in addition to disease surveillance in wildlife. PMID:28877846

Emotional intelligence in incarcerated men with psychopathic traits

PubMed Central

Ermer, Elsa; Kahn, Rachel E.; Salovey, Peter; Kiehl, Kent A.

2012-01-01

The expression, recognition, and communication of emotional states are ubiquitous features of the human social world. Emotional intelligence (EI) is defined as the ability to perceive, manage, and reason about emotions, in oneself and others. Individuals with psychopathy have numerous difficulties in social interaction and show impairment on some emotional tasks. Here we investigate the relation between emotional intelligence and psychopathy in a sample of incarcerated men (n=374), using the Psychopathy Checklist—Revised (PCL-R; Hare, 2003) and the Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT; Mayer, Salovey, & Caruso, 2002). The MSCEIT is a well-validated ability-based emotional intelligence measure that does not rely on self-report judgments of emotional skills. The Hare PCL-R is the gold-standard for the assessment of psychopathy in clinical populations. Controlling for general intelligence, psychopathy was associated with lower emotional intelligence. These findings suggest individuals with psychopathy are impaired on a range of emotional intelligence abilities and that emotional intelligence is an important area for understanding deficits in psychopathy. PMID:22329657

XYY chromosome abnormality in sexual homicide perpetrators.

PubMed

Briken, Peer; Habermann, Niels; Berner, Wolfgang; Hill, Andreas

2006-03-05

In a retrospective investigation of the court reports about sexual homicide perpetrators chromosome analysis had been carried out in 13 of 166 (7.8%) men. Three men (1.8%) with XYY chromosome abnormality were found. This rate is much higher than that found in unselected samples of prisoners (0.7-0.9%) or in the general population (0.01%). The three men had shown prepubescent abnormalities, school problems, and had suffered from physical abuse. The chromosome analysis in all cases had been carried out in connection with the forensic psychiatric court report due to the sexual homicide. However, two men had earlier psychiatric referrals. All were diagnosed as sexual sadistic, showed a psychopathic syndrome or psychopathy according to the Psychopathy Checklist-Revised [Hare RD, 1991, The Hare Psychopathy Checklist-Revised, Toronto, Ontario, Canada: Multi-Health Systems]. Two were multiple murderers. Especially forensic psychiatrists should be vigilant of the possibility of XYY chromosome abnormalities in sexual offenders. (c) 2006 Wiley-Liss, Inc.

Anthropogenic noise playback impairs embryonic development and increases mortality in a marine invertebrate

NASA Astrophysics Data System (ADS)

Nedelec, Sophie L.; Radford, Andrew N.; Simpson, Stephen D.; Nedelec, Brendan; Lecchini, David; Mills, Suzanne C.

2014-07-01

Human activities can create noise pollution and there is increasing international concern about how this may impact wildlife. There is evidence that anthropogenic noise may have detrimental effects on behaviour and physiology in many species but there are few examples of experiments showing how fitness may be directly affected. Here we use a split-brood, counterbalanced, field experiment to investigate the effect of repeated boat-noise playback during early life on the development and survival of a marine invertebrate, the sea hare Stylocheilus striatus at Moorea Island (French Polynesia). We found that exposure to boat-noise playback, compared to ambient-noise playback, reduced successful development of embryos by 21% and additionally increased mortality of recently hatched larvae by 22%. Our work, on an understudied but ecologically and socio-economically important taxon, demonstrates that anthropogenic noise can affect individual fitness. Fitness costs early in life have a fundamental influence on population dynamics and resilience, with potential implications for community structure and function.

Chemical composition of inks of diverse marine molluscs suggests convergent chemical defenses.

PubMed

Derby, Charles D; Kicklighter, Cynthia E; Johnson, P M; Zhang, Xu

2007-05-01

Some marine molluscs, notably sea hares, cuttlefish, squid, and octopus, release ink when attacked by predators. The sea hare Aplysia californica releases secretions from the ink gland and opaline gland that protect individuals from injury or death from predatory spiny lobsters through a combination of mechanisms that include chemical deterrence, sensory disruption, and phagomimicry. The latter two mechanisms are facilitated by millimolar concentrations of free amino acids (FAA) in sea hare ink and opaline, which stimulate the chemosensory systems of predators, ultimately leading to escape by sea hares. We hypothesize that other inking molluscs use sensory disruption and/or phagomimicry as a chemical defense. To investigate this, we examined concentrations of 21 FAA and ammonium in the defensive secretions of nine species of inking molluscs: three sea hares (Aplysia californica, Aplysia dactylomela, Aplysia juliana) and six cephalopods (cuttlefish: Sepia officinalis; squid: Loligo pealei, Lolliguncula brevis, Dosidicus gigas; octopus: Octopus vulgaris, Octopus bimaculoides). We found millimolar levels of total FAA and ammonium in these secretions, and the FAA in highest concentration were taurine, aspartic acid, glutamic acid, alanine, and lysine. Crustaceans and fish, which are major predators of these molluscs, have specific receptor systems for these FAA. Our chemical analysis supports the hypothesis that inking molluscs have the potential to use sensory disruption and/or phagomimicry as a chemical defense.

Physiological responses in air traffic control personnel : O'Hare Tower.

DOT National Transportation Integrated Search

1971-01-01

Physiological and biochemical measurements were made on 22 air traffic controllers at O'Hare tower during five days of the heavy traffic evening shift (1600-2400) and five days of the light traffic morning shift (0000-0800). : Pulse rates were higher...

Survey of Visual Ground Aids at O'Hare International Airport.

DOT National Transportation Integrated Search

1975-01-01

During the period June - July 1974 a survey of Visual Ground Aids was conducted at O'Hare International Airport in Chicago, Illinois. The purpose of this survey was to identify equipment currently installed to aid in providing visual guidance to pilo...

Aircraft wake vortex takeoff tests at O'Hare International Airport

DOT National Transportation Integrated Search

1994-08-01

Three wake vortex measurement systems (anemometer, acoustic doppler, and laser : doppler) were used to collect wake vortex data from aircraft departing Runway 22L at : Chicago's O'Hare airport for nine months in 1980. The data were analyzed to determ...

Relationship between heavy metal accumulation and morphometric parameters in European hare (Lepus europaeus) inhabiting various types of landscapes in southern Poland.

PubMed

Wajdzik, Marek; Halecki, Wiktor; Kalarus, Konrad; Gąsiorek, Michał; Pająk, Marek

2017-11-01

To evaluate the influence of hazardous substances in the environment, studies of pollutant accumulation in wild living animals are needed. Studies dealing with heavy metal contamination in mammals usually focus on a single organ. We investigated accumulation of heavy metals as well as iron in European hare (Lepus europaeus) living in southern Poland, Małopolska Province. Hares were captured during the hunting season. We tested metal accumulation in 14 organs and tissues using 35 individuals with known body weight and sex inhabiting agricultural, industrial and other types of landscapes. To obtain deeper insight into contamination patterns, we used accumulation data from the liver since it is the most frequently investigated organ and prone to pollution accumulation. Based on the data obtained for the liver, we tested the impact of metal pollution on hare morphology, including body length and several skull cranimetric parameters. Metals content differed between organs. Moreover, individuals from industrial areas had higher Cd content in their body. We distinguished two groups of elements: the first group, Cd, Fe and Zn, revealed the highest toxic effect in the liver and kidneys; the second group, Cr, Ni, and Pb, accumulated primarily in the brain. Hares inhabiting industrial areas had higher concentration of Cd and Pb, and lower levels of Cr and Fe in their liver in comparison with those from agricultural and forest habitats. Heavy metals had an effect on body length that was negatively associated with Cr levels. Skull diastema length was associated positively with accumulation of Cd and Pb. We showed that hare organs and tissues could be used as bioindicators of environmental pollution by heavy metals. Copyright © 2017 Elsevier Inc. All rights reserved.

Influence of precommercial thinning on snowshoe hares.

Treesearch

Evelyn L. Bull; Thad W. Heater; Abe A. Clark; Jay F. Shepherd; Arlene K. Blumton

2005-01-01

Relative abundance, survival, home range, and habitat use of snowshoe hares (Lepus americanus) were evaluated in five precommercial thinning treatments in lodgepole pine (Pinus contorta Dougl. ex Loud.) stands in northeastern Oregon between June 2000 and July 2003. A combination of track surveys, trapping grids, and...

A cluster of tularaemia after contact with a dead hare in the Netherlands.

PubMed

van de Wetering, D; Oliveira dos Santos, C; Wagelaar, M; de Kleuver, M; Koene, M G J; Roest, H I J; Sinha, B; Tomaso, H; Bierman, W F W; Stienstra, Y

2015-12-01

Tularemia is thought to be rare in the Netherlands. Here we describe a cluster of two patients who contracted tularaemia after field dressing of a hare found dead. Additionally, infection from the same source is suggested in three animals.

Molecular evolution and antigenic variation of European brown hare syndrome virus (EBHSV).

PubMed

Lopes, Ana M; Capucci, Lorenzo; Gavier-Widén, Dolores; Le Gall-Reculé, Ghislaine; Brocchi, Emiliana; Barbieri, Ilaria; Quéméner, Agnès; Le Pendu, Jacques; Geoghegan, Jemma L; Holmes, Edward C; Esteves, Pedro J; Abrantes, Joana

2014-11-01

European brown hare syndrome virus (EBHSV) is the aetiological agent of European brown hare syndrome (EBHS), a disease affecting Lepus europaeus and Lepus timidus first diagnosed in Sweden in 1980. To characterize EBHSV evolution we studied hare samples collected in Sweden between 1982 and 2008. Our molecular clock dating is compatible with EBHSV emergence in the 1970s. Phylogenetic analysis revealed two lineages: Group A persisted until 1989 when it apparently suffered extinction; Group B emerged in the mid-1980s and contains the most recent strains. Antigenic differences exist between groups, with loss of reactivity of some MAbs over time, which are associated with amino acid substitutions in recognized epitopes. A role for immune selection is also supported by the presence of positively selected codons in exposed regions of the capsid. Hence, EBHSV evolution is characterized by replacement of Group A by Group B viruses, suggesting that the latter possess a selective advantage. Copyright © 2014 Elsevier Inc. All rights reserved.

Environmental surveillance during an outbreak of tularaemia in hares, the Netherlands, 2015.

PubMed

Janse, Ingmar; Maas, Miriam; Rijks, Jolianne M; Koene, Miriam; van der Plaats, Rozemarijn Qj; Engelsma, Marc; van der Tas, Peter; Braks, Marieta; Stroo, Arjan; Notermans, Daan W; de Vries, Maaike C; Reubsaet, Frans; Fanoy, Ewout; Swaan, Corien; Kik, Marja Jl; IJzer, Jooske; Jaarsma, Ryanne I; van Wieren, Sip; de Roda-Husman, Ana Maria; van Passel, Mark; Roest, Hendrik-Jan; van der Giessen, Joke

2017-08-31

Tularaemia, a disease caused by the bacterium Francisella tularensis, is a re-emerging zoonosis in the Netherlands. After sporadic human and hare cases occurred in the period 2011 to 2014, a cluster of F. tularensis-infected hares was recognised in a region in the north of the Netherlands from February to May 2015. No human cases were identified, including after active case finding. Presence of F. tularensis was investigated in potential reservoirs and transmission routes, including common voles, arthropod vectors and surface waters. F. tularensis was not detected in common voles, mosquito larvae or adults, tabanids or ticks. However, the bacterium was detected in water and sediment samples collected in a limited geographical area where infected hares had also been found. These results demonstrate that water monitoring could provide valuable information regarding F. tularensis spread and persistence, and should be used in addition to disease surveillance in wildlife. This article is copyright of The Authors, 2017.

The transcriptional landscape of seasonal coat colour moult in the snowshoe hare.

PubMed

Ferreira, Mafalda S; Alves, Paulo C; Callahan, Colin M; Marques, João P; Mills, L Scott; Good, Jeffrey M; Melo-Ferreira, José

2017-08-01

Seasonal coat colour change is an important adaptation to seasonally changing environments but the evolution of this and other circannual traits remains poorly understood. In this study, we use gene expression to understand seasonal coat colour moulting in wild snowshoe hares (Lepus americanus). We used hair colour to follow the progression of the moult, simultaneously sampling skin from three moulting stages in hares collected during the peak of the spring moult from white winter to brown summer pelage. Using RNA sequencing, we tested whether patterns of expression were consistent with predictions based on the established phases of the hair growth cycle. We found functionally consistent clustering across skin types, with 766 genes differentially expressed between moult stages. "White" pelage showed more differentially expressed genes that were upregulated relative to other skin types, involved in the transition between late telogen (quiescent stage) and the onset of anagen (proliferative stage). Skin samples from transitional "intermediate" and "brown" pelage were transcriptionally similar and resembled the regressive transition to catagen (regressive stage). We also detected differential expression of several key circadian clock and pigmentation genes, providing important means to dissect the bases of alternate seasonal colour morphs. Our results reveal that pelage colour is a useful biomarker for seasonal change but that there is a consistent lag between the main gene expression waves and change in visible coat colour. These experiments establish that developmental sampling from natural populations of nonmodel organisms can provide a crucial resource to dissect the genetic basis and evolution of complex seasonally changing traits. © 2017 John Wiley & Sons Ltd.

Airport Surface Traffic Control Concept Formulation Study : Volume 3. Operations Analysis of O'Hare Airport - Part 2.

DOT National Transportation Integrated Search

1975-07-01

The volume presents the results of the quantitative analyses of the O'Hare ASTC System operations. The operations environments for the periods selected for detailed analysis of the ASDE films and controller communications recording are described. Fol...

O'Hare ASDE-2 radome performance in rain : analysis and improvement.

DOT National Transportation Integrated Search

1973-03-01

The operational performance of the ASDE-2 radar at O'Hare Airport is severely limited during periods of moderate to heavy rainfall. Using the system performance specifications, an estimate has been made of the ASDE-2's tolerance to power loss and deg...

Airport Surface Traffic Control Concept Formulation Study : Volume II. Operations Analysis of O'Hare Airport - Part 1

DOT National Transportation Integrated Search

1975-07-01

The report describes the approach followed and the analysis techniques employed in the performance of the operations analysis of the current ASTC system for the baseline airport, O'Hare International Airport, Chicago, Illinois. It also describes the ...

Biochemical responses and oxidative stress in Francisella tularensis infection: a European brown hare model

PubMed Central

2011-01-01

Background The aim of the present study was to investigate biochemical and oxidative stress responses to experimental F. tularensis infection in European brown hares, an important source of human tularemia infections. Methods For these purposes we compared the development of an array of biochemical parameters measured in blood plasma using standard procedures of dry chemistry as well as electrochemical devices following a subcutaneous infection with a wild Francisella tularensis subsp. holarctica strain (a single dose of 2.6 × 109 CFU pro toto). Results Subcutaneous inoculation of a single dose with 2.6 × 109 colony forming units of a wild F. tularensis strain pro toto resulted in the death of two out of five hares. Plasma chemistry profiles were examined on days 2 to 35 post-infection. When compared to controls, the total protein, urea, lactate dehydrogenase, aspartate aminotransferase and alanine aminotransferase were increased, while albumin, glucose and amylase were decreased. Both uric and ascorbic acids and glutathione dropped on day 2 and then increased significantly on days 6 to 12 and 6 to 14 post-inoculation, respectively. There was a two-fold increase in lipid peroxidation on days 4 to 8 post-inoculation. Conclusions Contrary to all expectations, the present study demonstrates that the European brown hare shows relatively low susceptibility to tularemia. Therefore, the circumstances of tularemia in hares under natural conditions should be further studied. PMID:21232117

Analysis of Ground-Wind Vortex Sensing System Data from O'Hare International Airport

DOT National Transportation Integrated Search

1980-09-01

From July 1976 through September 1977, aircraft wake vortex data were collected on the approach to runways 14R, 27R, and 32L at O'Hare International Airport. The vortices from over 21,000 aircraft were tracked using the propeller anemometer Ground-Wi...

Socioreligious Semantic Space in Small Nonconformist Communities: A South African Study.

ERIC Educational Resources Information Center

Stones, Christopher R.

1988-01-01

Examined the structure of semantic space (Evaluative-Potency-Activity) among four socioreligious communities in South Africa: Jesus People, Hare Krishna Devotees; Maharaj Ji Premies; and Catholic Seminarians. Found significant differences among all groups, particularly in semantic structure between the Jesus People and the Hare Krishna groups; and…

Validity of Rorschach Inkblot scores for discriminating psychopaths from non-psychopaths in forensic populations: a meta-analysis.

PubMed

Wood, James M; Lilienfeld, Scott O; Nezworski, M Teresa; Garb, Howard N; Allen, Keli Holloway; Wildermuth, Jessica L

2010-06-01

Gacono and Meloy (2009) have concluded that the Rorschach Inkblot Test is a sensitive instrument with which to discriminate psychopaths from nonpsychopaths. We examined the association of psychopathy with 37 Rorschach variables in a meta-analytic review of 173 validity coefficients derived from 22 studies comprising 780 forensic participants. All studies included the Hare Psychopathy Checklist or one of its versions (Hare, 1980, 1991, 2003) and Exner's (2003) Comprehensive System for the Rorschach. Mean validity coefficients of Rorschach variables in the meta-analysis ranged from -.113 to .239, with a median validity of .070 and a mean validity of .062. Psychopathy displayed a significant and medium-sized association with the number of Aggressive Potential responses (weighted mean validity coefficient = .232) and small but significant associations with the Sum of Texture responses, Cooperative Movement = 0, the number of Personal responses, and the Egocentricity Index (weighted mean validity coefficients = .097 to .159). The remaining 32 Rorschach variables were not significantly related to psychopathy. The present findings contradict the view that the Rorschach is a clinically sensitive instrument for discriminating psychopaths from nonpsychopaths.

Fire drives transcontinental variation in tree birch defense against browsing by snowshoe hares

Treesearch

John P. Bryant; Thomas P. Clausen; Robert K. Swihart; Simon M. Landhäusser; Michael T. Stevens; Christopher D. B. Hawkins; Suzanne Carrière; Andrei P. Kirilenko; Alasdair M. Veitch; Richard A. Popko; David T. Cleland; Joseph H. Williams; Walter J. Jakubas; Michael R. Carlson; Karin Lehmkuhl Bodony; Merben Cebrian; Thomas F. Paragi; Peter M. Picone; Jeffery E. Moore; Edmond C. Packee; Thomas Malone

2009-01-01

Fire has been the dominant disturbance in boreal America since the Pleistocene, resulting in a spatial mosaic in which the most fire occurs in the continental northwest. Spatial variation in snowshoe hare (Lepus americanus) density reflects the fire mosaic. Because fire initiates secondary forest succession, a fire mosaic creates...

Inhibition of snowshoe hare succinate dehydrogenase activity as a mechanism of deterrence for papyriferic acid in birch

Treesearch

Jennifer Sorensen Forbey; Xinzhu Pu; Dong Xu; Knut Kielland; John Bryant

2011-01-01

The plant secondary metabolite papyriferic acid (PA) deters browsing by snowshoe hares (Lepus americanus) on the juvenile developmental stage of the Alaska paper birch (Betula neoalaskana). However, the physiological mechanism that reduces browsing remains unknown. We used pharmacological assays and molecular modeling to test the...

75 FR 20672 - Notice of Submission Deadline for Schedule Information for O'Hare International Airport, John F...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-20

...'s O'Hare International Airport (ORD), New York's John F. Kennedy International Airport (JFK), and.... SUPPLEMENTARY INFORMATION: The FAA has designated ORD as an IATA Level 2, Schedules Facilitated Airport, and JFK and EWR as Level 3, Coordinated Airports. The scheduled operations at JFK and EWR are currently...

The Content Validity of Juvenile Psychopathy: An Empirical Examination

ERIC Educational Resources Information Center

Lynam, Donald R.; Derefinko, Karen J.; Caspi, Avshalom; Loeber, Rolf; Stouthamer-Loeber, Magda

2007-01-01

This study examined the content validity of a juvenile psychopathy measure, the Childhood Psychopathy Scale (CPS; D. R. Lynam, 1997), based on a downward translation of an adult instrument, the Hare Psychopathy Checklist-Revised (PCL-R; R. D. Hare, 1991). The CPS was compared with two other indices of juvenile psychopathy: (a) an index derived…

Mycosporine-like amino acids are multifunctional molecules in sea hares and their marine community

PubMed Central

Kicklighter, Cynthia E.; Kamio, Michiya; Nguyen, Linh; Germann, Markus W.; Derby, Charles D.

2011-01-01

Molecules of keystone significance are relatively rare, yet mediate a variety of interactions between organisms. They influence the distribution and abundance of species, the transfer of energy across multiple trophic levels, and thus they play significant roles in structuring ecosystems. Despite their potential importance in facilitating our understanding of ecological systems, only three molecules thus far have been proposed as molecules of keystone significance: saxitoxin and dimethyl sulfide in marine communities and tetrodotoxin in riparian communities. In the course of studying the neuroecology of chemical defenses, we identified three mycosporine-like amino acids (MAAs)—N-ethanol palythine (= asterina-330), N-isopropanol palythine (= aplysiapalythine A), and N-ethyl palythine (= aplysiapalythine B)—as intraspecific alarm cues for sea hares (Aplysia californica). These alarm cues are released in the ink secretion of sea hares and cause avoidance behaviors in neighboring conspecifics. Further, we show that these three bioactive MAAs, two [aplysiapalythine A (APA) and -B (APB)] being previously unknown molecules, are present in the algal diet of sea hares and are concentrated in their defensive secretion as well as in their skin. MAAs are known to be produced by algae, fungi, and cyanobacteria and are acquired by many aquatic animals through trophic interactions. MAAs are widely used as sunscreens, among other uses, but sea hares modify their function to serve a previously undocumented role, as intraspecific chemical cues. Our findings highlight the multifunctionality of MAAs and their role in ecological connectivity, suggesting that they may function as molecules of keystone significance in marine ecosystems. PMID:21709250

Detection of rabbit and hare processed material in compound feeds by TaqMan real-time PCR.

PubMed

Pegels, N; López-Calleja, I; García, T; Martín, R; González, I

2013-01-01

Food and feed traceability has become a priority for governments due to consumer demand for comprehensive and integrated safety policies. In the present work, a TaqMan real-time PCR assay targeting the mitochondrial 12S rRNA gene was developed for specific detection of rabbit and hare material in animal feeds and pet foods. The technique is based on the use of three species-specific primer/probe detection systems targeting three 12S rRNA gene fragments: one from rabbit species, another one from hare species and a third fragment common to rabbit and hare (62, 102 and 75 bp length, respectively). A nuclear 18S rRNA PCR system, detecting a 77-bp amplicon, was used as positive amplification control. Assay performance and sensitivity were assessed through the analysis of a batch of laboratory-scale feeds treated at 133°C at 3 bar for 20 min to reproduce feed processing conditions dictated by European regulations. Successful detection of highly degraded rabbit and hare material was achieved at the lowest target concentration assayed (0.1%). Furthermore, the method was applied to 96 processed commercial pet food products to determine whether correct labelling had been used at the market level. The reported real-time PCR technique detected the presence of rabbit tissues in 80 of the 96 samples analysed (83.3%), indicating a possible labelling fraud in some pet foods. The real-time PCR method reported may be a useful tool for traceability purposes within the framework of feed control.

Alternative prey use affects helminth parasite infections in grey wolves.

PubMed

Friesen, Olwyn C; Roth, James D

2016-09-01

Predators affect prey populations not only through direct predation, but also by acting as definitive hosts for their parasites and completing parasite life cycles. Understanding the affects of parasitism on prey population dynamics requires knowing how their predators' parasite community is affected by diet and prey availability. Ungulates, such as moose (Alces americanus) and white-tailed deer (Odocoileus virginianus), are often important prey for wolves (Canis lupus), but wolves also consume a variety of alternative prey, including beaver (Castor canadensis) and snowshoe hare (Lepus americanus). The use of alternative prey, which may host different or fewer parasites than ungulates, could potentially reduce overall abundance of ungulate parasites within the ecosystem, benefiting both wolves and ungulate hosts. We examined parasites in wolf carcasses from eastern Manitoba and estimated wolf diet using stable isotope analysis. Taeniidae cestodes were present in most wolves (75%), reflecting a diet primarily comprised of ungulates, but nematodes were unexpectedly rare. Cestode abundance was negatively related to the wolf's δ(13) C value, indicating diet affects parasite abundance. Wolves that consumed a higher proportion of beaver and caribou (Rangifer tarandus), estimated using Bayesian mixing models, had lower cestode abundance, suggesting the use of these alternative prey can reduce parasite loads. Long-term consumption of beavers may lower the abundance of adult parasites in wolves, eventually lowering parasite density in the region and ultimately benefiting ungulates that serve as intermediate hosts. Thus, alternative prey can affect both predator-prey and host-parasite interactions and potentially affect food web dynamics. © 2016 The Authors. Journal of Animal Ecology © 2016 British Ecological Society.

Gemini 4 prime crew with Official medical nurse for Astronaut crew members

NASA Technical Reports Server (NTRS)

1965-01-01

Gemini 4 prime crew, Astronauts Edward H. White II, (left), and James A. McDivitt (right) are shown with Lt. Dolores (Dee) O'Hare, US Air Force, Center Medical Office, Flight Medicine Branch, Manned Spaceflight Center (MSC). Lieutenant O'Hare has served during several space flights as Official medical nurse for the astronaut crew members on the missions.

The Role of Antisociality in the Psychopathy Construct: Comment on Skeem and Cooke (2010)

ERIC Educational Resources Information Center

Hare, Robert D.; Neumann, Craig S.

2010-01-01

J. Skeem and D. J. Cooke (2010) asserted that Hare and Neumann consider criminality to be an essential component of the psychopathy construct. The assertion, presented in the guise of a debate on the nature of psychopathy, is neither accurate nor consistent with the clinical and empirical literature on psychopathy to which Hare and Neumann have…

Using Teacher Stories to Reveal Quality Educational Practice: An Eastern Cape Experience

ERIC Educational Resources Information Center

Paige, Kathryn; Chartres, Mike; Kenyon, Alan

2008-01-01

The University of Fort Hare Distance Education Project set out to improve qualifications of primary teachers in rural and township schools in the Eastern Cape of the Republic of South Africa. At the culmination of an 11-year AUSAid collaboration between the University of Fort Hare and University of South Australia a research project to reveal…

Waterborne outbreak of tularemia associated with crayfish fishing.

PubMed Central

Anda, P.; Segura del Pozo, J.; Díaz García, J. M.; Escudero, R.; García Peña, F. J.; López Velasco, M. C.; Sellek, R. E.; Jiménez Chillarón, M. R.; Sánchez Serrano, L. P.; Martínez Navarro, J. F.

2001-01-01

In 1997, an outbreak of human tularemia associated with hare-hunting in central Spain affected 585 patients. We describe the identification of Francisella tularensis biovar palaearctica in a second outbreak of ulceroglandular tularemia associated with crayfish (Procambarus clarkii) fishing in a contaminated freshwater stream distant from the hare-associated outbreak. The second outbreak occurred 1 year after the first. PMID:11485678

SHOWN WITH NURSE - ASTRONAUT EDWARD H. WHITE II - MISC. - CAPE

NASA Image and Video Library

1965-06-01

S65-29657 (June 1965) --- Gemini-4 prime crew, astronauts Edward H. White II (left), and James A. McDivitt are shown with Lt. Dolores (Dee) O'Hare, US Air Force, Center Medical Office, Flight Medicine Branch, Manned Spacecraft Center (MSC). Lieutenant O'Hare has served during several spaceflights as official medical nurse for the astronaut crew members on the missions.

14 CFR 93.25 - Initial assignment of Arrival Authorizations to U.S. and Canadian air carriers for domestic and U...

Code of Federal Regulations, 2010 CFR

2010-01-01

... Chicago O'Hare International Airport § 93.25 Initial assignment of Arrival Authorizations to U.S. and... August 18, 2004, “Order Limiting Scheduled Operations at O'Hare International Airport.” A carrier's total assignment under this paragraph shall be reduced accordingly by (i) any international Arrival Authorizations...

Effect of age and gender on carcass traits and meat quality of farmed brown hares.

PubMed

Trocino, A; Birolo, M; Dabbou, S; Gratta, F; Rigo, N; Xiccato, G

2018-04-01

A total of 48 sub-adult hares and adult reproducing farmed hares were used to characterize carcass and meat traits according to the age and gender of animals. With respect to carcass traits, when age increased, the carcass weight significantly increased (2022 to 3391 g; P<0.001), but dressing out percentages did not change. The dissectible fat (1.3% to 2.2%; P<0.05) and Longissimus lumborum (LL) proportions (13.5% to 14.5%; P<0.001) and muscle-to-bone ratio of hind legs (5.11 to 6.23; P<0.001) increased, whereas the hind leg proportions decreased (37.3% to 36.3%; P=0.01). As for the meat quality, the pH of hind leg (5.74 to 5.83; P<0.001) and LL (5.53 to 5.69; P<0.001) increased with age, while the L* index decreased in both cuts (42.9 to 34.4 in hind leg; 45.1 to 40.3 in LL; P<0.001). The redness index increased at the hind leg (4.07 to 5.76; P<0.001), while it decreased at LL (3.03 to 1.46; P<0.001). In the case of the hind leg, meat thawing losses decreased (1.58% to 1.02%), and shear force increased (2.97 to 4.02 kg/g). In the case of LL, thawing losses decreased (8.79% to 4.91%; P<0.001) in the adult hares compared with the sub-adult ones. Meat water and protein contents decreased in the hind leg and LL of the adult hares compared with the sub-adult ones, whereas ether extract increased in a restricted range in LL only (0.92% to 1.11%; P<0.001). In the case of the hind leg, the rate of the saturated fatty acids (SFA) decreased (41.0% to 26.7%), and the rate of the polyunsaturated fatty acids (PUFA) increased (34.0% to 45.3%) (P<0.001). In the case of LL, SFA (38.6% to 42.9%) and monounsaturated fatty acids (19.4% to 27.2%) increased, whereas PUFA decreased (42.0% to 30.1%) when the age increased (P<0.001). Gender affected only the slaughter results and carcass traits. In conclusion, farmed hares have favourable slaughter results (high dressing percentage), carcass traits (high hind legs and loins rates), and meat nutritional value (high-protein, low-fat meat). This fact would offer additional commercial opportunities, in addition to restocking, to hare farmers.

Dynamic multistate site occupancy models to evaluate hypotheses relevant to conservation of Golden Eagles in Denali National Park, Alaska

USGS Publications Warehouse

Martin, Julien; McIntyre, Carol L.; Hines, James E.; Nichols, James D.; Schmutz, Joel A.; MacCluskie, Margaret C.

2009-01-01

The recent development of multistate site occupancy models offers great opportunities to frame and solve decision problems for conservation that can be viewed in terms of site occupancy. These models have several characteristics (e.g., they account for detectability) that make them particularly well suited for addressing management and conservation problems. We applied multistate site occupancy models to evaluate hypotheses related to the conservation and management of Golden Eagles (Aquila chrysaetos) in Denali National Park, Alaska, and provided estimates of transition probabilities among three occupancy states for nesting areas (occupied with successful reproduction, occupied with unsuccessful reproduction, and unoccupied). Our estimation models included the effect of potential recreational activities (hikers) and environmental covariates such as a snowshoe hare (Lepus americanus) index on transition probabilities among the three occupancy states. Based on the most parsimonious model, support for the hypothesis of an effect of potential human disturbance on site occupancy dynamics was equivocal. There was some evidence that potential human disturbance negatively affected local colonization of territories, but there was no evidence of an effect on reproductive performance parameters. In addition, models that assume a positive relationship between the hare index and successful reproduction were well supported by the data. The statistical approach that we used is particularly useful to parameterize management models that can then be used to make optimal decisions related to the management of Golden Eagles in Denali. Although in our case we were particularly interested in managing recreational activities, we believe that such models should be useful to for a broad class of management and conservation problems.

76 FR 56868 - Notice of Submission Deadline for Schedule Information for O'Hare International Airport, John F...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-14

... Chicago's O'Hare International Airport (ORD), New York's John F. Kennedy International Airport (JFK), and... designated ORD as an IATA Level 2 airport, JFK as a Level 3 airport, and EWR as a Level 3 airport. Scheduled operations at JFK and EWR are currently limited by FAA Orders until a final Congestion Management Rule for...

Ecology of lynx in northern Canada and Alaska [Chapter 9

Treesearch

Garth Mowat; Kim G. Poole; Mark O' Donoghue

2000-01-01

We review the ecology of lynx in the northern part of its range, drawing heavily on the results of recent research from that region. Snowshoe hares form the bulk of prey items in essentially all studies and at all periods in the cycle, but use of alternative prey, often red squirrel, increases as hares become scarce. Caching of freshly killed prey is rare,...

Home-loving boreal hare mitochondria survived several invasions in Iberia: the relative roles of recurrent hybridisation and allele surfing

PubMed Central

Melo-Ferreira, J; Farelo, L; Freitas, H; Suchentrunk, F; Boursot, P; Alves, P C

2014-01-01

Genetic introgression from a resident species into an invading close relative can result from repeated hybridisation along the invasion front and/or allele surfing on the expansion wave. Cases where the phenomenon is massive and systematic, such as for hares (genus Lepus) in Iberia, would be best explained by recurrent hybridisation but this is difficult to prove because the donor populations are generally extinct. In the Pyrenean foothills, Lepus europaeus presumably replaced Lepus granatensis recently and the present species border is parallel to the direction of invasion, so that populations of L. granatensis in the contact zone represent proxies of existing variation before the invasion. Among three pairs of populations sampled across this border, we find less differentiation of mitochondrial DNA (mtDNA) across than along it, as predicted under recurrent hybridisation at the invasion front. Using autosomal microsatellite loci and X- and Y-linked diagnostic loci, we show that admixture across the border is quasi-absent, making it unlikely that lack of interspecific mtDNA differentiation results from ongoing gene flow. Furthermore, we find that the local species ranges are climatically contrasted, making it also unlikely that ongoing ecology-driven movement of the contact account for mtDNA introgression. The lack of mtDNA differentiation across the boundary is mostly due to sharing of mtDNA from a boreal species currently extinct in Iberia (Lepus timidus) whose mitochondria have thus remained in place since the last deglaciation despite successive invasions by two other species. Home-loving mitochondria thus witness past species distribution rather than ongoing exchanges across stabilised contact zones. PMID:24149657

Peak energy turnover in lactating European hares: the role of fat reserves

PubMed Central

Valencak, T. G.; Tataruch, F.; Ruf, T.

2010-01-01

SUMMARY European hares (Lepus europaeus) in central Europe have high energetic costs of reproduction, mainly due to precocial, rapidly growing young that rely largely on energy rich milk. Thus, hares in this climate build up large fat stores during winter which are then gradually depleted during the spring to autumn breeding season. We hypothesized that diminishing fat stores of females over the breeding season may affect resource allocation, peak energy assimilation during lactation, or the total investment in offspring. Therefore, we measured energy intake, milk quality and milk production throughout lactation in spring, summer and autumn, in females raising (size-manipulated) litters with three young each, under natural photoperiod but at buffered ambient temperatures inside our facility. Over the course of the breeding season the amount of milk production remained constant but fat content of the milk decreased. Hence, total energy transfer to young decreased significantly in autumn. By using undecanoic acid as a tracer of body fat mobilization we were able to show that milk fat partially originated from maternal fat stores particularly in spring. Peak sustained energy assimilation rates of lactating females were significantly higher in autumn, due to increased rates of food intake. We conclude that fat stores allow female hares to downregulate energy intake and expenditure early in the breeding season whereas late breeding forces them to reach peak energy intake levels. Accordingly, we suggest that in hares, peak energy turnover during lactation varies with the availability of fat reserves. Limits to sustained metabolic rate serve as variable constraints on reproductive investment. There may be a trade-off in energetic costs to mothers rearing early vs. late litters in the year. PMID:19112142

Alpine glacial relict species losing out to climate change: The case of the fragmented mountain hare population (Lepus timidus) in the Alps.

PubMed

Rehnus, Maik; Bollmann, Kurt; Schmatz, Dirk R; Hackländer, Klaus; Braunisch, Veronika

2018-03-13

Alpine and Arctic species are considered to be particularly vulnerable to climate change, which is expected to cause habitat loss, fragmentation and-ultimately-extinction of cold-adapted species. However, the impact of climate change on glacial relict populations is not well understood, and specific recommendations for adaptive conservation management are lacking. We focused on the mountain hare (Lepus timidus) as a model species and modelled species distribution in combination with patch and landscape-based connectivity metrics. They were derived from graph-theory models to quantify changes in species distribution and to estimate the current and future importance of habitat patches for overall population connectivity. Models were calibrated based on 1,046 locations of species presence distributed across three biogeographic regions in the Swiss Alps and extrapolated according to two IPCC scenarios of climate change (RCP 4.5 & 8.5), each represented by three downscaled global climate models. The models predicted an average habitat loss of 35% (22%-55%) by 2100, mainly due to an increase in temperature during the reproductive season. An increase in habitat fragmentation was reflected in a 43% decrease in patch size, a 17% increase in the number of habitat patches and a 34% increase in inter-patch distance. However, the predicted changes in habitat availability and connectivity varied considerably between biogeographic regions: Whereas the greatest habitat losses with an increase in inter-patch distance were predicted at the southern and northern edges of the species' Alpine distribution, the greatest increase in patch number and decrease in patch size is expected in the central Swiss Alps. Finally, both the number of isolated habitat patches and the number of patches crucial for maintaining the habitat network increased under the different variants of climate change. Focusing conservation action on the central Swiss Alps may help mitigate the predicted effects of climate change on population connectivity. © 2018 John Wiley & Sons Ltd.

The Entry Psychiatric Screen (EPS): A Psychiatric Screening Procedure for Applicants for Military Service

DTIC Science & Technology

2004-12-01

Structured Clinical Interview for DSM-IV-TR (First, et al., 2001) and the Hare Psychopathy Checklist (Hart, Cox, & Hare, 1995). In total, 96 induction...psychotic characteristics. EPS Antisocial Scale Here again, the lack of participants in our sample who manifested clinical levels of psychopathy ... Psychopathy Checklist revealed that no members of our sample met the criteria for clinical psychopathy . For each of the three remaining diagnostic

Landscape structure and management alter the outcome of a pesticide ERA: Evaluating impacts of endocrine disruption using the ALMaSS European Brown Hare model.

PubMed

Topping, Chris J; Dalby, Lars; Skov, Flemming

2016-01-15

There is a gradual change towards explicitly considering landscapes in regulatory risk assessment. To realise the objective of developing representative scenarios for risk assessment it is necessary to know how detailed a landscape representation is needed to generate a realistic risk assessment, and indeed how to generate such landscapes. This paper evaluates the contribution of landscape and farming components to a model based risk assessment of a fictitious endocrine disruptor on hares. In addition, we present methods and code examples for generation of landscape structures and farming simulation from data collected primarily for EU agricultural subsidy support and GIS map data. Ten different Danish landscapes were generated and the ERA carried out for each landscape using two different assumed toxicities. The results showed negative impacts in all cases, but the extent and form in terms of impacts on abundance or occupancy differed greatly between landscapes. A meta-model was created, predicting impact from landscape and farming characteristics. Scenarios based on all combinations of farming and landscape for five landscapes representing extreme and middle impacts were created. The meta-models developed from the 10 real landscapes failed to predict impacts for these 25 scenarios. Landscape, farming, and the emergent density of hares all influenced the results of the risk assessment considerably. The study indicates that prediction of a reasonable worst case scenario is difficult from structural, farming or population metrics; rather the emergent properties generated from interactions between landscape, management and ecology are needed. Meta-modelling may also fail to predict impacts, even when restricting inputs to combinations of those used to create the model. Future ERA may therefore need to make use of multiple scenarios representing a wide range of conditions to avoid locally unacceptable risks. This approach could now be feasible Europe wide given the landscape generation methods presented.

Brasilenyne and cis-dihydrorhodophytin: Antifeedant medium-ring haloethers from a sea hare (Aplysia brasiliana)

PubMed Central

Kinnel, R. B.; Dieter, R. K.; Meinwald, J.; Van Engen, D.; Clardy, J.; Eisner, T.; Stallard, M. O.; Fenical, W.

1979-01-01

Two straight-chain C15 fish antifeedants have been isolated from the sea hare Aplysia brasiliana. Chemical, spectral, and x-ray diffraction studies led to the characterization of these medium-ring ethers as brasilenyne (2) and cis-dihydrorhodophytin (3). The oxonin ring system of 2 is novel in nature. Biosynthetic considerations permit the postulation that a third compound, a noncrystalline congener of these compounds, is cis-isodihydrohodophytin (4). PMID:16592687

Tularemia, plague, yersiniosis, and Tyzzer’s disease in wild rodents and lagomorphs in Canada: A review

PubMed Central

Wobeser, Gary; Campbell, G. Douglas; Dallaire, André; McBurney, Scott

2009-01-01

Information related to infection of wild rodents or lagomorphs in Canada by Francisella tularensis, Yersinia pestis, other Yersinia spp., and Clostridium piliforme was searched for this study. Reports on tularemia in humans linked to these species came from diagnostic databases, literature, wildlife health specialists, and public health agencies. Tularemia has been diagnosed in 8 species of wild rodent and 2 species in the genus Lepus in Canada. Tularemia occurred in wild animals, or in humans associated with these species, in all jurisdictions except the Yukon and Nunavut. Tularemia was diagnosed most frequently in beaver, muskrats, and snowshoe hares, and although tularemia is closely linked to cottontail rabbits in the USA, it has not been reported in cottontails in Canada. Tularemia in humans was associated with muskrats and hares more commonly than with beaver. Plague was diagnosed in bushy-tailed woodrats in British Columbia in 1988. Based on surveys, Y. pestis may occur enzootically in southern Alberta, Saskatchewan, and British Columbia. Infection with Yersinia pseudotuberculosis and Y. enterocolitica has been diagnosed in beaver, muskrats, and snowshoe hares in many provinces. Tyzzer’s disease has been diagnosed in muskrats in British Columbia, Saskatchewan, Ontario, and Quebec and in snowshoe hares in Ontario. Infection with these bacteria is likely much more frequent than indicated by diagnostic records. PMID:20190973

Role of predation in short-term population fluctuations of some birds and mammals in Fennoscandia.

PubMed

Angelstam, P; Lindström, E; Widén, P

1984-05-01

We tested the hypothesis that synchronous fluctuations in small game species in boreal Fennoscandia are caused by varying predation pressure. The main prey of predators are the cyclically superabundant voles. Small game species (alternative prey) are rare compared to voles. The following 4 predictions were checked: (1) Predators should shift their diet from main prey to alternative prey as main prey decline. - This was confirmed using data on red fox (Vulpes vulpes L.) diet.; (2) The mortality rate of alternative prey should be inversely correlated to the abundance of main prey. - This was true for mountain hare (Lepus timidus L.) mortality rates and the rate of nest predation on black grouse (Tetrao tetrix L.).; (3) The total consumption of prey by all the predators should at least equal the critical losses in alternative prey during a decline year. - A tentative estimate of predator consumption amounted to 10 times the losses in grouse and hare.; and (4) The absence of synchrony between the species in the boreonemoral region should be associated with a more diverse diet of predators. - This was the case for red fox diets throughout Sweden. Although all 4 predictions were confirmed, we could not necessarily exclude other hypotheses involving changes in quality or quantity of plant food.

Molecular characterization of Babesia species in wild animals and their ticks in Turkey.

PubMed

Orkun, Ömer; Karaer, Zafer

2017-11-01

To date, no study has investigated Babesia ecology in wild boars, hares or foxes in Turkey. This study aimed to determine and characterize Babesia spp. in wild animals and their ticks. We identified a novel Babesia genotype and four known Babesia species in wild animals and their ticks. We detected Babesia spp. molecularly in hares for the first time. In addition, we identified B. vulpes in foxes for the first time in Turkey. The presence of B. rossi, B. crassa and B. occultans was also revealed in ticks collected from wild boars and hares. This is only the second report of B. rossi in ticks outside of Africa and suggests that B. rossi is circulating in ticks in Turkey. Therefore B. rossi poses a significant threat to domestic dogs. Here we demonstrate the role of wild animals in the life cycle of Babesia species in Turkey and contribute to Babesia ecological and taxonomic information. Copyright © 2017 Elsevier B.V. All rights reserved.

Wildlife Population Dynamics in Human-Dominated Landscapes under Community-Based Conservation: The Example of Nakuru Wildlife Conservancy, Kenya

PubMed Central

Ogutu, Joseph O.; Kuloba, Bernard; Piepho, Hans-Peter; Kanga, Erustus

2017-01-01

Wildlife conservation is facing numerous and mounting challenges on private and communal lands in Africa, including in Kenya. We analyze the population dynamics of 44 common wildlife species in relation to rainfall variation in the Nakuru Wildlife Conservancy (NWC), located in the Nakuru-Naivasha region of Kenya, based on ground total counts carried out twice each year from March 1996 to May 2015. Rainfall in the region was quasi-periodic with cycle periods dependent on the rainfall component and varying from 2.8 years for the dry season to 10.9 years for the wet season. These oscillations are associated with frequent severe droughts and food scarcity for herbivores. The trends for the 44 wildlife species showed five general patterns during 1996–2015. 1) Steinbuck, bushbuck, hartebeest and greater kudu numbers declined persistently and significantly throughout 1996–2015 and thus merit the greatest conservation attention. 2) Klipspringer, mongoose, oribi, porcupine, cheetah, leopard, ostrich and Sykes monkey numbers also decreased noticeably but not significantly between 1996 and 2015. 3) Dik dik, eland, African hare, Jackal, duiker, hippo and Thomson’s gazelle numbers first increased and then declined between 1996 and 2015 but only significantly for duiker and hippo. 4) Aardvark, serval cat, colobus monkey, bat-eared fox, reedbuck, hyena and baboon numbers first declined and then increased but only the increases in reedbuck and baboon numbers were significant. 5) Grant’s gazelle, Grevy’s zebra, lion, spring hare, Burchell’s zebra, bushpig, white rhino, rock hyrax, topi, oryx, vervet monkey, guinea fowl, giraffe, and wildebeest numbers increased consistently between 1996 and 2015. The increase was significant only for rock hyrax, topi, vervet monkey, guinea fowl, giraffe and wildebeest. 6) Impala, buffalo, warthog, and waterbuck, numbers increased significantly and then seemed to level off between 1996 and 2015. The aggregate biomass of primates and carnivores increased overall whereas that of herbivores first increased from 1996 to 2006 and then levelled off thereafter. Aggregate herbivore biomass increased linearly with increasing cumulative wet season rainfall. The densities of the 30 most abundant species were either strongly positively or negatively correlated with cumulative past rainfall, most commonly with the early wet season component. The collaborative wildlife conservation and management initiatives undertaken on the mosaic of private, communal and public lands were thus associated with increase or no decrease in numbers of 32 and decrease in numbers of 12 of the 44 species. Despite the decline by some species, effective community-based conservation is central to the future of wildlife in the NWC and other rangelands of Kenya and beyond and is crucially dependent on the good will, effective engagement and collective action of local communities, working in partnerships with various organizations, which, in NWC, operated under the umbrella of the Nakuru Wildlife Forum. PMID:28103269

Wildlife Population Dynamics in Human-Dominated Landscapes under Community-Based Conservation: The Example of Nakuru Wildlife Conservancy, Kenya.

PubMed

Ogutu, Joseph O; Kuloba, Bernard; Piepho, Hans-Peter; Kanga, Erustus

2017-01-01

Wildlife conservation is facing numerous and mounting challenges on private and communal lands in Africa, including in Kenya. We analyze the population dynamics of 44 common wildlife species in relation to rainfall variation in the Nakuru Wildlife Conservancy (NWC), located in the Nakuru-Naivasha region of Kenya, based on ground total counts carried out twice each year from March 1996 to May 2015. Rainfall in the region was quasi-periodic with cycle periods dependent on the rainfall component and varying from 2.8 years for the dry season to 10.9 years for the wet season. These oscillations are associated with frequent severe droughts and food scarcity for herbivores. The trends for the 44 wildlife species showed five general patterns during 1996-2015. 1) Steinbuck, bushbuck, hartebeest and greater kudu numbers declined persistently and significantly throughout 1996-2015 and thus merit the greatest conservation attention. 2) Klipspringer, mongoose, oribi, porcupine, cheetah, leopard, ostrich and Sykes monkey numbers also decreased noticeably but not significantly between 1996 and 2015. 3) Dik dik, eland, African hare, Jackal, duiker, hippo and Thomson's gazelle numbers first increased and then declined between 1996 and 2015 but only significantly for duiker and hippo. 4) Aardvark, serval cat, colobus monkey, bat-eared fox, reedbuck, hyena and baboon numbers first declined and then increased but only the increases in reedbuck and baboon numbers were significant. 5) Grant's gazelle, Grevy's zebra, lion, spring hare, Burchell's zebra, bushpig, white rhino, rock hyrax, topi, oryx, vervet monkey, guinea fowl, giraffe, and wildebeest numbers increased consistently between 1996 and 2015. The increase was significant only for rock hyrax, topi, vervet monkey, guinea fowl, giraffe and wildebeest. 6) Impala, buffalo, warthog, and waterbuck, numbers increased significantly and then seemed to level off between 1996 and 2015. The aggregate biomass of primates and carnivores increased overall whereas that of herbivores first increased from 1996 to 2006 and then levelled off thereafter. Aggregate herbivore biomass increased linearly with increasing cumulative wet season rainfall. The densities of the 30 most abundant species were either strongly positively or negatively correlated with cumulative past rainfall, most commonly with the early wet season component. The collaborative wildlife conservation and management initiatives undertaken on the mosaic of private, communal and public lands were thus associated with increase or no decrease in numbers of 32 and decrease in numbers of 12 of the 44 species. Despite the decline by some species, effective community-based conservation is central to the future of wildlife in the NWC and other rangelands of Kenya and beyond and is crucially dependent on the good will, effective engagement and collective action of local communities, working in partnerships with various organizations, which, in NWC, operated under the umbrella of the Nakuru Wildlife Forum.

Effects of protective fencing on birds, lizards, and black-tailed hares in the Western Mojave Desert

USGS Publications Warehouse

Brooks, M.

1999-01-01

Effects of protective fencing on birds, lizards, black-tailed hares (Lepus californicus), perennial plant cover, and structural diversity of perennial plants were evaluated from spring 1994 through winter 1995 at the Desert Tortoise Research Natural Area (DTNA), in the Mojave Desert, California. Abundance and species richness of birds were higher inside than outside the DTNA, and effects were larger during breeding than wintering seasons and during a high than a low rainfall year. Ash-throated flycatchers (Myiarchus cinerascens), cactus wrens (Campylorhynchus brunneicapillus), LeConte's thrashers (Toxostoma lecontei), loggerhead shrikes (Lanius ludovicianus), sage sparrows (Amphispiza belli), and verdins (Auriparus flaviceps) were more abundant inside than outside the DTNA. Nesting activity was also more frequent inside. Total abundance and species richness of lizards and individual abundances of western whiptail lizards (Cnemidophorous tigris) and desert spiny lizards (Sceloporus magister) were higher inside than outside. In contrast, abundance of black-tailed hares was lower inside. Structural diversity of the perennial plant community did not differ due to protection, but cover was 50% higher in protected areas. Black-tailed hares generally prefer areas of low perennial plant cover, which may explain why they were more abundant outside than inside the DTNA. Habitat structure may not affect bird and lizard communities as much as availability of food at this desert site, and the greater abundance and species richness of vertebrates inside than outside the DTNA may correlate with abundances of seeds and invertebrate prey.

[The incidence of tularemia in Slovakia in 1997-2008].

PubMed

Gurycová, D; Tináková, K; Výrosteková, V; Gacíková, E

2010-02-01

Analysis of epidemiological trends in tularemia in the Slovak Republic (SR) over the last 12 years and changes in the epidemiology of this infection. The sources of data for the epidemiological analysis are the SR annual tularemia surveillance report, records of epidemiological investigation of reported cases and knowledge from long-term surveillance of natural foci. The incidence of tularemia was analyzed based on the standard epidemiological indicators and in relation to infection sources and transmission routes. In 1997-2008, a total of 453 tularemia cases were reported from all administrative regions in Slovakia, the mean incidence was 0.71/10(5) population and 95.4% of cases were reported in the West, with the predominance of cases in the Nitra region where the mean incidence was 4/10(5) population. In the outbreak of 2002, the incidence of tularemia was as high as 18 cases/10(5) population. Tularemia cases were reported in all age groups and more than half of the patients were aged between 30 to 59 years. Tularemia cases were 1.9 times more frequent in males than in females. The seasonal trend peaked in summer, month of July. In a greater proportion of cases, 58.5%, the source of infection was other than brown hares, 16.3%, which correlates well with the decrease in the hare tularemia foci in the study period. The most frequent route of transmission was work exposure to contaminated animal feed and bedding and in an dusty environment with increased occurrence of small rodents. The proportion of tick-borne and biting insect-borne cases was 12.8% and 12.4% of cases were not elucidated epidemiologically. Clinical manifestations were ulceroglandular and glandular tularemia in 55.6%, pulmonary tularemia in 21.2 %, oroglandular tularaemia in 18.8% and other forms of tularaemia in 4.4%. The changes in the distribution of sources of infection and routes of transmission resulted in changed epidemiological characteristics and clinical forms of tularemia in Slovakia. The importance of tularemia surveillance is underlined.

Keith Haring, Felix Gonzalez-Torres, Wolfgang Tillmans, and the AIDS Epidemic: The Use of Visual Art in a Health Humanities Course.

PubMed

Smith, Jason A

2018-02-23

Contemporary art can be a powerful pedagogical tool in the health humanities. Students in an undergraduate course in the health humanities explore the subjective experience of illness and develop their empathy by studying three artists in the context of the AIDS epidemic: Keith Haring, Felix Gonzalez-Torres, and Wolfgang Tillmans. Using assignments based in narrative pedagogy, students expand their empathic response to pain and suffering. The role of visual art in health humanities pedagogy is discussed.

HARE: Final Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mckie, Jim

2012-01-09

This report documents the results of work done over a 6 year period under the FAST-OS programs. The first effort was called Right-Weight Kernels, (RWK) and was concerned with improving measurements of OS noise so it could be treated quantitatively; and evaluating the use of two operating systems, Linux and Plan 9, on HPC systems and determining how these operating systems needed to be extended or changed for HPC, while still retaining their general-purpose nature. The second program, HARE, explored the creation of alternative runtime models, building on RWK. All of the HARE work was done on Plan 9. Themore » HARE researchers were mindful of the very good Linux and LWK work being done at other labs and saw no need to recreate it. Even given this limited funding, the two efforts had outsized impact: _ Helped Cray decide to use Linux, instead of a custom kernel, and provided the tools needed to make Linux perform well _ Created a successor operating system to Plan 9, NIX, which has been taken in by Bell Labs for further development _ Created a standard system measurement tool, Fixed Time Quantum or FTQ, which is widely used for measuring operating systems impact on applications _ Spurred the use of the 9p protocol in several organizations, including IBM _ Built software in use at many companies, including IBM, Cray, and Google _ Spurred the creation of alternative runtimes for use on HPC systems _ Demonstrated that, with proper modifications, a general purpose operating systems can provide communications up to 3 times as effective as user-level libraries Open source was a key part of this work. The code developed for this project is in wide use and available at many places. The core Blue Gene code is available at https://bitbucket.org/ericvh/hare. We describe details of these impacts in the following sections. The rest of this report is organized as follows: First, we describe commercial impact; next, we describe the FTQ benchmark and its impact in more detail; operating systems and runtime research follows; we discuss infrastructure software; and close with a description of the new NIX operating system, future work, and conclusions.« less

Past, present and future distributions of an Iberian Endemic, Lepus granatensis: ecological and evolutionary clues from species distribution models.

PubMed

Acevedo, Pelayo; Melo-Ferreira, José; Real, Raimundo; Alves, Paulo Célio

2012-01-01

The application of species distribution models (SDMs) in ecology and conservation biology is increasing and assuming an important role, mainly because they can be used to hindcast past and predict current and future species distributions. However, the accuracy of SDMs depends on the quality of the data and on appropriate theoretical frameworks. In this study, comprehensive data on the current distribution of the Iberian hare (Lepus granatensis) were used to i) determine the species' ecogeographical constraints, ii) hindcast a climatic model for the last glacial maximum (LGM), relating it to inferences derived from molecular studies, and iii) calibrate a model to assess the species future distribution trends (up to 2080). Our results showed that the climatic factor (in its pure effect and when it is combined with the land-cover factor) is the most important descriptor of the current distribution of the Iberian hare. In addition, the model's output was a reliable index of the local probability of species occurrence, which is a valuable tool to guide species management decisions and conservation planning. Climatic potential obtained for the LGM was combined with molecular data and the results suggest that several glacial refugia may have existed for the species within the major Iberian refugium. Finally, a high probability of occurrence of the Iberian hare in the current species range and a northward expansion were predicted for future. Given its current environmental envelope and evolutionary history, we discuss the macroecology of the Iberian hare and its sensitivity to climate change.

Past, Present and Future Distributions of an Iberian Endemic, Lepus granatensis: Ecological and Evolutionary Clues from Species Distribution Models

PubMed Central

Acevedo, Pelayo; Melo-Ferreira, José; Real, Raimundo; Alves, Paulo Célio

2012-01-01

The application of species distribution models (SDMs) in ecology and conservation biology is increasing and assuming an important role, mainly because they can be used to hindcast past and predict current and future species distributions. However, the accuracy of SDMs depends on the quality of the data and on appropriate theoretical frameworks. In this study, comprehensive data on the current distribution of the Iberian hare (Lepus granatensis) were used to i) determine the species’ ecogeographical constraints, ii) hindcast a climatic model for the last glacial maximum (LGM), relating it to inferences derived from molecular studies, and iii) calibrate a model to assess the species future distribution trends (up to 2080). Our results showed that the climatic factor (in its pure effect and when it is combined with the land-cover factor) is the most important descriptor of the current distribution of the Iberian hare. In addition, the model’s output was a reliable index of the local probability of species occurrence, which is a valuable tool to guide species management decisions and conservation planning. Climatic potential obtained for the LGM was combined with molecular data and the results suggest that several glacial refugia may have existed for the species within the major Iberian refugium. Finally, a high probability of occurrence of the Iberian hare in the current species range and a northward expansion were predicted for future. Given its current environmental envelope and evolutionary history, we discuss the macroecology of the Iberian hare and its sensitivity to climate change. PMID:23272115

Comparative analysis of early ontogeny in Bursatella leachii and Aplysia californica

PubMed Central

Vue, Zer; Capo, Thomas R.; Bardales, Ana T.

2014-01-01

Opisthobranch molluscs exhibit fascinating body plans associated with the evolution of shell loss in multiple lineages. Sea hares in particular are interesting because Aplysia californica is a well-studied model organism that offers a large suite of genetic tools. Bursatella leachii is a related tropical sea hare that lacks a shell as an adult and therefore lends itself to comparative analysis with A. californica. We have established an enhanced culturing procedure for B. leachii in husbandry that enabled the study of shell formation and loss in this lineage with respect to A. californica life staging. PMID:25538871

Neuronal Cell Cultures from Aplysia for High-Resolution Imaging of Growth Cones

PubMed Central

Lee, Aih Cheun; Decourt, Boris; Suter, Daniel

2008-01-01

Neuronal growth cones are the highly motile structures at the tip of axons that can detect guidance cues in the environment and transduce this information into directional movement towards the appropriate target cell. To fully understand how guidance information is transmitted from the cell surface to the underlying dynamic cytoskeletal networks, one needs a model system suitable for live cell imaging of protein dynamics at high temporal and spatial resolution. Typical vertebrate growth cones are too small to quantitatively analyze F-actin and microtubule dynamics. Neurons from the sea hare Aplysia californica are 5-10 times larger than vertebrate neurons, can easily be kept at room temperature and are very robust cells for micromanipulation and biophysical measurements. Their growth cones have very defined cytoplasmic regions and a well-described cytoskeletal system. The neuronal cell bodies can be microinjected with a variety of probes for studying growth cone motility and guidance. In the present protocol we demonstrate a procedure for dissection of the abdominal ganglion, culture of bag cell neurons and setting up an imaging chamber for live cell imaging of growth cones. PMID:19066568

Gyrfalcon diet in central west Greenland during the nesting period

USGS Publications Warehouse

Booms, T.L.; Fuller, M.R.

2003-01-01

We studied food habits of Gyrfalcons (Falco rusticolus) nesting in central west Greenland in 2000 and 2001 using three sources of data: time-lapse video (3 nests), prey remains (22 nests), and regurgitated pellets (19 nests). These sources provided different information describing the diet during the nesting period. Gyrfalcons relied heavily on Rock Ptarmigan (Lagopus mutus) and arctic hares (Lepus arcticus). Combined, these species contributed 79-91% of the total diet, depending on the data used. Passerines were the third most important group. Prey less common in the diet included waterfowl, arctic fox pups (Alopex lagopus), shorebirds, gulls, alcids, and falcons. All Rock Ptarmigan were adults, and all but one arctic hare were young of the year. Most passerines were fledglings. We observed two diet shifts, first from a preponderance of ptarmigan to hares in mid-June, and second to passerines in late June. The video-monitored Gyrfalcons consumed 94-110 kg of food per nest during the nestling period, higher than previously estimated. Using a combination of video, prey remains, and pellets was important to accurately document Gyrfalcon diet, and we strongly recommend using time-lapse video in future diet studies to identify biases in prey remains and pellet data.

Gyrfalcon diet in central west Greenland during the nestling period

USGS Publications Warehouse

Booms, Travis; Fuller, Mark R.

2003-01-01

We studied food habits of Gyrfalcons (Falco rusticolus) nesting in central west Greenland in 2000 and 2001 using three sources of data: time-lapse video (3 nests), prey remains (22 nests), and regurgitated pellets (19 nests). These sources provided different information describing the diet during the nesting period. Gyrfalcons relied heavily on Rock Ptarmigan (Lagopus mutus) and arctic hares (Lepus arcticus). Combined, these species contributed 79-91% of the total diet, depending on the data used. Passerines were the third most important group. Prey less common in the diet included waterfowl, arctic fox pups (Alopex lagopus), shorebirds, gulls, alcids, and falcons. All Rock Ptarmigan were adults, and all but one arctic hare were young of the year. Most passerines were fledglings. We observed two diet shifts, first from a preponderance of ptarmigan to hares in mid-June, and second to passerines in late June. The video-monitored Gyrfalcons consumed 94-110 kg of food per nest during the nestling period, higher than previously estimated. Using a combination of video, prey remains, and pellets was important to accurately document Gyrfalcon diet, and we strongly recommend using time-lapse video in future diet studies to identify biases in prey remains and pellet data.

Wildlife-vehicle collisions in Croatia--a hazard for humans and animals.

PubMed

Sprem, Nikica; Duduković, Dejan; Keros, Tomislav; Konjević, Dean

2013-06-01

Wildlife-vehicle collisions (WVC) have increased and now there is a world-wide problem related to significant mortality of wildlife, habitat fragmentation, change in behavior and even disappearance of local endangered populations. Along with these deleterious effects on wildlife, WVC can also result in injuries and deaths of humans. During the three-year monitoring, a total of 7,495 wildlife-vehicle collisions were recorded, including mainly roe deer (73%), while other species were less frequently affected (wild boar--9%; brown hare--5%; and red deer and pheasant each with 4%). Incidence of wildlife-vehicle collisions were observed according to territorial distribution, seasonal and daily occurrence and type of road (total and per 1 km).

Mixture models for estimating the size of a closed population when capture rates vary among individuals

USGS Publications Warehouse

Dorazio, R.M.; Royle, J. Andrew

2003-01-01

We develop a parameterization of the beta-binomial mixture that provides sensible inferences about the size of a closed population when probabilities of capture or detection vary among individuals. Three classes of mixture models (beta-binomial, logistic-normal, and latent-class) are fitted to recaptures of snowshoe hares for estimating abundance and to counts of bird species for estimating species richness. In both sets of data, rates of detection appear to vary more among individuals (animals or species) than among sampling occasions or locations. The estimates of population size and species richness are sensitive to model-specific assumptions about the latent distribution of individual rates of detection. We demonstrate using simulation experiments that conventional diagnostics for assessing model adequacy, such as deviance, cannot be relied on for selecting classes of mixture models that produce valid inferences about population size. Prior knowledge about sources of individual heterogeneity in detection rates, if available, should be used to help select among classes of mixture models that are to be used for inference.

Why Do the Boreal Forest Ecosystems of Northwestern Europe Differ from Those of Western North America?

PubMed

Boonstra, Rudy; Andreassen, Harry P; Boutin, Stan; Hušek, Jan; Ims, Rolf A; Krebs, Charles J; Skarpe, Christina; Wabakken, Petter

2016-09-01

The boreal forest is one of the largest terrestrial biomes on Earth. Conifers normally dominate the tree layer across the biome, but other aspects of ecosystem structure and dynamics vary geographically. The cause of the conspicuous differences in the understory vegetation and the herbivore-predator cycles between northwestern Europe and western North America presents an enigma. Ericaceous dwarf shrubs and 3- to 4-year vole-mustelid cycles characterize the European boreal forests, whereas tall deciduous shrubs and 10-year snowshoe hare-lynx cycles characterize the North American ones. We discuss plausible explanations for this difference and conclude that it is bottom-up: Winter climate is the key determinant of the dominant understory vegetation that then determines the herbivore-predator food-web interactions. The crucial unknown for the twenty-first century is how climate change and increasing instability will affect these forests, both with respect to the dynamics of individual plant and animal species and to their community interactions.

Meta-ethnography 25 years on: challenges and insights for synthesising a large number of qualitative studies.

PubMed

Toye, Francine; Seers, Kate; Allcock, Nick; Briggs, Michelle; Carr, Eloise; Barker, Karen

2014-06-21

Studies that systematically search for and synthesise qualitative research are becoming more evident in health care, and they can make an important contribution to patient care. Our team was funded to complete a meta-ethnography of patients' experience of chronic musculoskeletal pain. It has been 25 years since Noblit and Hare published their core text on meta-ethnography, and the current health research environment brings additional challenges to researchers aiming to synthesise qualitative research. Noblit and Hare propose seven stages of meta-ethnography which take the researcher from formulating a research idea to expressing the findings. These stages are not discrete but form part of an iterative research process. We aimed to build on the methods of Noblit and Hare and explore the challenges of including a large number of qualitative studies into a qualitative systematic review. These challenges hinge upon epistemological and practical issues to be considered alongside expectations about what determines high quality research. This paper describes our method and explores these challenges. Central to our method was the process of collaborative interpretation of concepts and the decision to exclude original material where we could not decipher a concept. We use excerpts from our research team's reflexive statements to illustrate the development of our methods.

Meta-ethnography 25 years on: challenges and insights for synthesising a large number of qualitative studies

PubMed Central

2014-01-01

Studies that systematically search for and synthesise qualitative research are becoming more evident in health care, and they can make an important contribution to patient care. Our team was funded to complete a meta-ethnography of patients’ experience of chronic musculoskeletal pain. It has been 25 years since Noblit and Hare published their core text on meta-ethnography, and the current health research environment brings additional challenges to researchers aiming to synthesise qualitative research. Noblit and Hare propose seven stages of meta-ethnography which take the researcher from formulating a research idea to expressing the findings. These stages are not discrete but form part of an iterative research process. We aimed to build on the methods of Noblit and Hare and explore the challenges of including a large number of qualitative studies into a qualitative systematic review. These challenges hinge upon epistemological and practical issues to be considered alongside expectations about what determines high quality research. This paper describes our method and explores these challenges. Central to our method was the process of collaborative interpretation of concepts and the decision to exclude original material where we could not decipher a concept. We use excerpts from our research team’s reflexive statements to illustrate the development of our methods. PMID:24951054

Comparative water metabolism of Barrow Island macropodid marsupials: hormonal versus behavioural-dependent mechanisms of body water conservation.

PubMed

King, J M; Bradshaw, S D

2008-01-15

Seasonal variations in rates of water turnover were measured over a 7-year period in four species of macropodid marsupials (Lagorchestes conspicillatus, Bettongia lesueur, Petrogale lateralis and Macropus robustus isabellinus), on Barrow Island off the arid Pilbara coast of Western Australia. These ranged from over 100 mL kg(-0.82) d(-1) in wet seasons to as low as 28.2 mL kg(-0.82) d(-1) in dry seasons in the Spectacled hare wallaby, L. conspicillatus. Plasma osmolality increased significantly in both Barrow Island euros (M. robustus isabellinus) and Spectacled hare wallabies in November 1994, in the driest year yet recorded on the island. In contrast, there was no change in plasma osmolality of the other two species (Black-footed rock wallaby, P. lateralis and Lesueur's burrowing bettong, B. lesueur) that exploit cool and humid thermal refugia such as caves and underground warrens to avoid diurnal temperature extremes. Plasma levels of the marsupial antidiuretic hormone (ADH), lysine vasopressin (LVP), were for the most part below the detectable limit of the assay of 0.41 pg mL(-1) in rock wallabies and bettongs, but reached high levels of 16.7+/-4.6 pg mL(-1) and 20.25+/-5.1 pg mL(-1) in euros and hare wallabies, respectively, in dry seasons. LVP levels were positively correlated with plasma osmolality in both euros and hare wallabies, and negatively correlated with total body water content in euros, supporting its rôle as an antidiuretic hormone in these two species. The study highlights the importance of environmental features, such as caves and underground warrens, which are critical for the long-term survival of endangered species such as the Black-footed rock wallaby and the Lesueur's bettong. These species appear to lack ADH-controlled renal systems for the conservation of body water and are thus dependent on behavioural strategies for the maintenance of fluid homeostasis in arid environments.

Parasites of wild animals as a potential source of hazard to humans.

PubMed

Gałęcki, Remigiusz; Sokół, Rajmund; Koziatek, Sylwia

2015-01-01

The decline in wild animal habitats and the uncontrolled growth of their population make these animals come closer to human settlements. The aim of the study was to identify parasitic infections in wild animals in the selected area, and to specify the hazards they create for humans. In more than 66% of the analysed faecal samples from wild boar, hares, roe deer, deer and fallow deer various developmental forms of parasites were found. These included parasites dangerous for humans: Toxocara canis, Capillaria hepatica, Capillaria bovis, Trichuris suis, Trichuris ovis, Trichuris globulosus, Eimeria spp., and Trichostongylus spp. It is necessary to monitor parasitic diseases in wild animals as they can lead to the spread of parasites creating a hazard to humans, pets and livestock.

Revisiting the classics: considering nonconsumptive effects in textbook examples of predator-prey interactions.

PubMed

Peckarsky, Barbara L; Abrams, Peter A; Bolnick, Daniel I; Dill, Lawrence M; Grabowski, Jonathan H; Luttbeg, Barney; Orrock, John L; Peacor, Scott D; Preisser, Evan L; Schmitz, Oswald J; Trussell, Geoffrey C

2008-09-01

Predator effects on prey dynamics are conventionally studied by measuring changes in prey abundance attributed to consumption by predators. We revisit four classic examples of predator-prey systems often cited in textbooks and incorporate subsequent studies of nonconsumptive effects of predators (NCE), defined as changes in prey traits (e.g., behavior, growth, development) measured on an ecological time scale. Our review revealed that NCE were integral to explaining lynx-hare population dynamics in boreal forests, cascading effects of top predators in Wisconsin lakes, and cascading effects of killer whales and sea otters on kelp forests in nearshore marine habitats. The relative roles of consumption and NCE of wolves on moose and consequent indirect effects on plant communities of Isle Royale depended on climate oscillations. Nonconsumptive effects have not been explicitly tested to explain the link between planktonic alewives and the size structure of the zooplankton, nor have they been invoked to attribute keystone predator status in intertidal communities or elsewhere. We argue that both consumption and intimidation contribute to the total effects of keystone predators, and that characteristics of keystone consumers may differ from those of predators having predominantly NCE. Nonconsumptive effects are often considered as an afterthought to explain observations inconsistent with consumption-based theory. Consequently, NCE with the same sign as consumptive effects may be overlooked, even though they can affect the magnitude, rate, or scale of a prey response to predation and can have important management or conservation implications. Nonconsumptive effects may underlie other classic paradigms in ecology, such as delayed density dependence and predator-mediated prey coexistence. Revisiting classic studies enriches our understanding of predator-prey dynamics and provides compelling rationale for ramping up efforts to consider how NCE affect traditional predator-prey models based on consumption, and to compare the relative magnitude of consumptive and NCE of predators.

Using Dynamic Risk and Protective Factors to Predict Inpatient Aggression: Reliability and Validity of START Assessments

PubMed Central

Desmarais, Sarah L.; Nicholls, Tonia L.; Wilson, Catherine M.; Brink, Johann

2012-01-01

The Short-Term Assessment of Risk and Treatability (START) is a relatively new structured professional judgment guide for the assessment and management of short-term risks associated with mental, substance use, and personality disorders. The scheme may be distinguished from other violence risk instruments because of its inclusion of 20 dynamic factors that are rated in terms of both vulnerability and strength. This study examined the reliability and validity of START assessments in predicting inpatient aggression. Research assistants completed START assessments for 120 male forensic psychiatric patients through review of hospital files. They additionally completed Historical-Clinical-Risk Management – 20 (HCR-20) and the Hare Psychopathy Checklist: Screening Version (PCL:SV) assessments. Outcome data was coded from hospital files for a 12-month follow-up period using the Overt Aggression Scale (OAS). START assessments evidenced excellent interrater reliability and demonstrated both predictive and incremental validity over the HCR-20 Historical subscale scores and PCL:SV total scores. Overall, results support the reliability and validity of START assessments, and use of the structured professional judgment approach more broadly, as well as the value of using dynamic risk and protective factors to assess violence risk. PMID:22250595

Headaches associated with refractive errors: myth or reality?

PubMed

Gil-Gouveia, R; Martins, I P

2002-04-01

Headache and refractive errors are very common conditions in the general population, and those with headache often attribute their pain to a visual problem. The International Headache Society (IHS) criteria for the classification of headache includes an entity of headache associated with refractive errors (HARE), but indicates that its importance is widely overestimated. To compare overall headache frequency and HARE frequency in healthy subjects with uncorrected or miscorrected refractive errors and a control group. We interviewed 105 individuals with uncorrected refractive errors and a control group of 71 subjects (with properly corrected or without refractive errors) regarding their headache history. We compared the occurrence of headache and its diagnosis in both groups and assessed its relation to their habits of visual effort and type of refractive errors. Headache frequency was similar in both subjects and controls. Headache associated with refractive errors was the only headache type significantly more common in subjects with refractive errors than in controls (6.7% versus 0%). It was associated with hyperopia and was unrelated to visual effort or to the severity of visual error. With adequate correction, 72.5% of the subjects with headache and refractive error reported improvement in their headaches, and 38% had complete remission of headache. Regardless of the type of headache present, headache frequency was significantly reduced in these subjects (t = 2.34, P =.02). Headache associated with refractive errors was rarely identified in individuals with refractive errors. In those with chronic headache, proper correction of refractive errors significantly improved headache complaints and did so primarily by decreasing the frequency of headache episodes.

Psychometric properties of the Hare Psychopathy Checklist-Revised (PCL-R) in a representative sample of Canadian federal offenders.

PubMed

Storey, Jennifer E; Hart, Stephen D; Cooke, David J; Michie, Christine

2016-04-01

The Hare Psychopathy Checklist-Revised (PCL-R; Hare, 2003) is a commonly used psychological test for assessing traits of psychopathic personality disorder. Despite the abundance of research using the PCL-R, the vast majority of research used samples of convenience rather than systematic methods to minimize sampling bias and maximize the generalizability of findings. This potentially complicates the interpretation of test scores and research findings, including the "norms" for offenders from the United States and Canada included in the PCL-R manual. In the current study, we evaluated the psychometric properties of PCL-R scores for all male offenders admitted to a regional reception center of the Correctional Service of Canada during a 1-year period (n = 375). Because offenders were admitted for assessment prior to institutional classification, they comprise a sample that was heterogeneous with respect to correctional risks and needs yet representative of all offenders in that region of the service. We examined the distribution of PCL-R scores, classical test theory indices of its structural reliability, the factor structure of test items, and the external correlates of test scores. The findings were highly consistent with those typically reported in previous studies. We interpret these results as indicating it is unlikely any sampling limitations of past research using the PCL-R resulted in findings that were, overall, strongly biased or unrepresentative. (c) 2016 APA, all rights reserved).

The Tortoise and the Hare. Small-Game Use, the Broad-Spectrum Revolution, and Paleolithic Demography.

PubMed

Stiner; Munro; Surovell

2000-02-01

This study illustrates the potential of small-game data for identifying and dating Paleolithic demographic pulses such as those associated with modern human origins and the later evolution of food-producing economies. Archaeofaunal series from Israel and Italy serve as our examples. Three important implications of this study are that (1) early Middle Paleolithic populations were exceptionally small and highly dispersed, (2) the first major population growth pulse in the eastern Mediterranean probably occurred before the end of the Middle Paleolithic, and (3) subsequent demographic pulses in the Upper and Epi-Paleolithic greatly reshaped the conditions of selection that operated on human subsistence ecology, technology, and society. The findings of this study are consistent with the main premise of Flannery's broad-spectrum-revolution hypothesis. However, ranking small prey in terms of work of capture (in the absence of special harvesting tools) proved far more effective in this investigation of human diet breadth than have the taxonomic-diversity analyses published previously.

Updated model assessment of pollution at major U. S. Airports

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yamartino, R.J.; Rote, D.M.

1979-02-01

The air quality impact of aircraft at and around Los Angeles International Airport (LAX) is simulated for hours of peak aircraft operation and worst case pollutant dispersion conditions. An updated version of the Argonne Airport Vicinity Air Pollution (AVAP) model is used in the simulation; model refinements reflect new theoretical formulations and data from field programs at LAX, O'Hare, and John F. Kennedy International Airports. Maximum carbon monoxide concentrations at LAX are found to be low relative to the NAAQS. Relatively high, widespread hydrocarbon levels indicate that aircraft emissions may aggravate oxidant problems near the airport. Concentrations of oxides ofmore » nitrogen are high enough relative to proposed standards to warrant further study. Similar modeling is underway for the O'Hare and JFK airports.« less

They know the words, but not the music: affective and semantic priming in individuals with psychopathy.

PubMed

Blair, K S; Richell, R A; Mitchell, D G V; Leonard, A; Morton, J; Blair, R J R

2006-08-01

Previous work has indicated dysfunctional affect-language interactions in individuals with psychopathy through use of the lexical decision task. However, it has been uncertain as to whether these deficits actually reflect impaired affect-language interactions or a more fundamental deficit in general semantic processing. In this study, we examined affective priming and semantic priming (dependent measures were reaction times and error rates) in individuals with psychopathy and comparison individuals, classified according to the psychopathy checklist revised (PCL-R) [Hare, R.D., 1991. The Hare Psychopathy Checklist-Revised. Multi-Health Systems, Toronto, Ont] Individuals with psychopathy showed significantly less affective priming relative to comparison individuals. In contrast, the two groups showed comparable levels of semantic priming. The results are discussed with reference to current models of psychopathy.

Using a general model of personality to identify the basic elements of psychopathy.

PubMed

Lynam, Donald R; Widiger, Thomas A

2007-04-01

In the present paper, we outline why we believe that factor analyses of the Hare Psychopathy Checklist Revised (Hare, 2003) are unlikely to yield the basic elements of psychopathy. As an alternative approach, we suggest embedding psychopathy within a broad model of general personality functioning, namely the five factor model (McCrae & Costa, 1990). Drawing on our previous work in the area using expert ratings, correlational approaches, and a "translation" of the PCL-R, we provide a consensus description of the core elements of psychopathy: extremely high interpersonal antagonism, pan-impulsivity, the absence of negative self-directed affect, the presence of angry hostility, and interpersonal assertiveness. We end with a discussion of the implications of this analysis for understanding, researching, and measuring psychopathy.

Comprehensive Enzymatic Analysis of the Cellulolytic System in Digestive Fluid of the Sea Hare Aplysia kurodai. Efficient Glucose Release from Sea Lettuce by Synergistic Action of 45 kDa Endoglucanase and 210 kDa ß-Glucosidase

PubMed Central

Tsuji, Akihiko; Tominaga, Keiko; Nishiyama, Nami; Yuasa, Keizo

2013-01-01

Although many endo-ß-1,4-glucanases have been isolated in invertebrates, their cellulolytic systems are not fully understood. In particular, gastropod feeding on seaweed is considered an excellent model system for production of bioethanol and renewable bioenergy from third-generation feedstocks (microalgae and seaweeds). In this study, enzymes involved in the conversion of cellulose and other polysaccharides to glucose in digestive fluids of the sea hare (Aplysia kurodai) were screened and characterized to determine how the sea hare obtains glucose from sea lettuce (Ulva pertusa). Four endo-ß-1,4-glucanases (21K, 45K, 65K, and 95K cellulase) and 2 ß-glucosidases (110K and 210K) were purified to a homogeneous state, and the synergistic action of these enzymes during cellulose digestion was analyzed. All cellulases exhibited cellulase and lichenase activities and showed distinct cleavage specificities against cellooligosaccharides and filter paper. Filter paper was digested to cellobiose, cellotriose, and cellotetraose by 21K cellulase, whereas 45K and 65K enzymes hydrolyzed the filter paper to cellobiose and glucose. 210K ß-glucosidase showed unique substrate specificity against synthetic and natural substrates, and 4-methylumbelliferyl (4MU)-ß-glucoside, 4MU–ß-galactoside, cello-oligosaccharides, laminarin, and lichenan were suitable substrates. Furthermore, 210K ß-glucosidase possesses lactase activity. Although ß-glucosidase and cellulase are necessary for efficient hydrolysis of carboxymethylcellulose to glucose, laminarin is hydrolyzed to glucose only by 210K ß-glucosidase. Kinetic analysis of the inhibition of 210K ß-glucosidase by D-glucono-1,5-lactone suggested the presence of 2 active sites similar to those of mammalian lactase-phlorizin hydrolase. Saccharification of sea lettuce was considerably stimulated by the synergistic action of 45K cellulase and 210K ß-glucosidase. Our results indicate that 45K cellulase and 210K ß-glucosidase are the core components of the sea hare digestive system for efficient production of glucose from sea lettuce. These findings contribute important new insights into the development of biofuel processing biotechnologies from seaweed. PMID:23762366

Hubble Catches a Galaxy Duo by the "Hare"

NASA Image and Video Library

2017-12-08

This image from the NASA/ESA Hubble Space Telescope shows the unusual galaxy IRAS 06076-2139, found in the constellation Lepus (The Hare). Hubble’s Wide Field Camera 3 (WFC3) and Advanced Camera for Surveys (ACS) instruments observed the galaxy from a distance of 500 million light-years. This particular object stands out from the crowd by actually being composed of two separate galaxies rushing past each other at about 2 million kilometers (1,243,000 miles) per hour. This speed is most likely too fast for them to merge and form a single galaxy. However, because of their small separation of only about 20,000 light-years, the galaxies will distort one another through the force of gravity while passing each other, changing their structures on a grand scale. Such galactic interactions are a common sight for Hubble, and have long been a field of study for astronomers. The intriguing behaviors of interacting galaxies take many forms; galactic cannibalism, galaxy harassment and even galaxy collisions. The Milky Way itself will eventually fall victim to the latter, merging with the Andromeda Galaxy in about 4.5 billion years. The fate of our galaxy shouldn’t be alarming though: while galaxies are populated by billions of stars, the distances between individual stars are so large that hardly any stellar collisions will occur. Credit: ESA/Hubble & NASA NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Molecular Investigation on the Presence of Hepatitis E Virus (HEV) in Wild Game in North-Western Italy.

PubMed

Serracca, Laura; Battistini, Roberta; Rossini, Irene; Mignone, Walter; Peletto, Simone; Boin, Claudia; Pistone, Giancarlo; Ercolini, Riccardo; Ercolini, Carlo

2015-09-01

Meat products from HEV-infected reservoir animal species are capable of transmitting HEV to humans and represent a public health concern. Human HEV cases have been linked to the consumption of raw or undercooked pig liver sausages, pork, and game meats, such as wild boars and deer worldwide. Direct exposure to swine or wild game species might also represent a source of HEV transmission especially for veterinarians, hunters, or butchers. A limited amount of data is available on HEV prevalence in wild boars in Italy and no data are available for other wild game species intended for human consumption. In this study, the circulation of HEV in four different animal species hunted in north-western Italy was evaluated to gain insight into the infection levels and the genetic diversity of the virus in such animal populations. Liver samples of 372 wild boars, 30 roe deer, 47 European hares and 38 coypus were analyzed for HEV RNA by real-time RT-PCR; positive samples were then sequenced and submitted to phylogenetic analysis. HEV RNA was detected in the livers of 7/372 (1.9%) wild boars tested, while no sample was positive for roe deer, European hare, and coypu. Phylogenetic analysis showed that wild boar HEV sequences belonged to HEV subtypes 3e, 3c, and 3f. Our results indicate that HEV is circulating only in wild boar among the considered game species in north-western Italy and suggest a potential zoonotic risk related to handling and/or consumption of raw or undercooked meat and products made of the liver from this species.

Seasonally Varying Predation Behavior and Climate Shifts Are Predicted to Affect Predator-Prey Cycles.

PubMed

Tyson, Rebecca; Lutscher, Frithjof

2016-11-01

The functional response of some predator species changes from a pattern characteristic for a generalist to that for a specialist according to seasonally varying prey availability. Current theory does not address the dynamic consequences of this phenomenon. Since season length correlates strongly with altitude and latitude and is predicted to change under future climate scenarios, including this phenomenon in theoretical models seems essential for correct prediction of future ecosystem dynamics. We develop and analyze a two-season model for the great horned owl (Bubo virginialis) and snowshoe hare (Lepus americanus). These species form a predator-prey system in which the generalist to specialist shift in predation pattern has been documented empirically. We study the qualitative behavior of this predator-prey model community as summer season length changes. We find that relatively small changes in summer season length can have a profound impact on the system. In particular, when the predator has sufficient alternative resources available during the summer season, it can drive the prey to extinction, there can be coexisting stable states, and there can be stable large-amplitude limit cycles coexisting with a stable steady state. Our results illustrate that the impacts of global change on local ecosystems can be driven by internal system dynamics and can potentially have catastrophic consequences.

Motion of Aircraft Wake Vortices in Ground Effect.

DOT National Transportation Integrated Search

2000-04-01

This report addresses the wake-turbulence separation standards for close-spaced parallel runways. Ground-wind anemometer data collected at Kennedy (landing) and O'Hare (takeoff) airports are analyzed to assess the lateral transport probability for wa...

14 CFR 93.123 - High density traffic airports.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Airport Class of user LaGuardia 4, 5 Newark O'Hare 2, 3, 5 Ronald Reagan National 1 Air carriers 48 40 120... aircraft operations at Ronald Reagan Washington National Airport, the term “commuters” means aircraft...

14 CFR 93.123 - High density traffic airports.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Airport Class of user LaGuardia 4, 5 Newark O'Hare 2, 3, 5 Ronald Reagan National 1 Air carriers 48 40 120... aircraft operations at Ronald Reagan Washington National Airport, the term “commuters” means aircraft...

mtDNA ribosomal gene phylogeny of sea hares in the genus Aplysia (Gastropoda, Opisthobranchia, Anaspidea): Implications for comparative neurobiology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Medina, Monica; Collins, Timothy M.; Walsh, Patrick J.

2000-08-10

Sea hares within the genus Aplysia are important neurobiological model organisms, and as studies based on different Aplysia species appear in the literature, a phylogenetic framework has become essential. We present a phylogenetic hypothesis for this genus, based on portions of two mitochondrial genes (12S and 16S). In addition, we reconstruct the evolution of several behavioral characters of interest to neurobiologists in order to illustrate the potential benefits of a phylogeny for the genus Aplysia. These benefits include the determination of ancestral traits, the direction and timing of evolution of characters, prediction of the distribution of traits, and identification ofmore » cases of independent acquisition of traits within lineages. This last benefit may prove especially useful in understanding the linkage between behaviors and their underlying neurological basis.« less

[Health surveillance of workers with prior exposure to asbestos. Application in the metallurgy/metal mechanical field].

PubMed

Rivolta, G; Della Foglia, M; Donelli, S; Riboldi, L

2006-01-01

To improve the health surveillance program for workers with a known previous exposure to asbestos in a big metallurgic-mechanical industry from Lombardy, the sources of risk and the different exposure levels hare been reconstructed based on specific jobs. The eligibility criteria and a specific work program including information and organization supports hare been established by a work group composed by health physicians, workers and industrial hygienists. The major goals of the program were: to listen and support each worker who perceives worries about his health status; to prevent, if possible, diseases, especially cancer, resulting from exposure; to document the existing injuries for legal compensation. The resulting actions consist of counselling; indication to follow an adequate life and work style; indication, based on specific request of worker, of sanitary checks of first or eventually second level.

The Elusive Nature of Adaptive Mitochondrial DNA Evolution of an Arctic Lineage Prone to Frequent Introgression

PubMed Central

Melo-Ferreira, José; Vilela, Joana; Fonseca, Miguel M.; da Fonseca, Rute R.; Boursot, Pierre; Alves, Paulo C.

2014-01-01

Mitochondria play a fundamental role in cellular metabolism, being responsible for most of the energy production of the cell in the oxidative phosphorylation (OXPHOS) pathway. Mitochondrial DNA (mtDNA) encodes for key components of this process, but its direct role in adaptation remains far from understood. Hares (Lepus spp.) are privileged models to study the impact of natural selection on mitogenomic evolution because 1) species are adapted to contrasting environments, including arctic, with different metabolic pressures, and 2) mtDNA introgression from arctic into temperate species is widespread. Here, we analyzed the sequences of 11 complete mitogenomes (ten newly obtained) of hares of temperate and arctic origins (including two of arctic origin introgressed into temperate species). The analysis of patterns of codon substitutions along the reconstructed phylogeny showed evidence for positive selection in several codons in genes of the OXPHOS complexes, most notably affecting the arctic lineage. However, using theoretical models, no predictable effect of these differences was found on the structure and physicochemical properties of the encoded proteins, suggesting that the focus of selection may lie on complex interactions with nuclear encoded peptides. Also, a cloverleaf structure was detected in the control region only from the arctic mtDNA lineage, which may influence mtDNA replication and transcription. These results suggest that adaptation impacted the evolution of hare mtDNA and may have influenced the occurrence and consequences of the many reported cases of massive mtDNA introgression. However, the origin of adaptation remains elusive. PMID:24696399

A comprehensive examination of the psychometric properties of the Hare Psychopathy Checklist-Revised in a Canadian multisite sample of indigenous and non-indigenous offenders.

PubMed

Olver, Mark E; Neumann, Craig S; Sewall, Lindsay A; Lewis, Kathy; Hare, Robert D; Wong, Stephen C P

2018-06-01

The present study examined the psychometric properties of Hare Psychopathy Checklist-Revised (PCL-R; Hare, 2003) scores in a multisite sample of 1,163 federally incarcerated Canadian indigenous and non-indigenous offenders from the Prairie Region of the Correctional Service of Canada. The research occurred against the backdrop of the Ewert v. Canada (2015) matter, in which the PCL-R was originally impugned in Federal Court for use with indigenous persons (later overturned in Canada v. Ewert, 2016). Indigenous men scored higher than non-indigenous men on most components of the PCL-R and had higher rates of recidivism, irrespective of follow-up. Discrimination analyses, however, supported the predictive efficacy of PCL-R total, factor, and facet scores for violent and general recidivism across both ancestral groups, with most group differences in area under the curve (AUC) magnitudes being small and nonsignificant. Calibration analyses demonstrated that higher PCL-R scores were associated with higher rates of general and violent recidivism for both ancestral groups, although higher recidivism rates were observed and estimated for indigenous men at specific PCL-R score thresholds. Confirmatory factor analyses supported the 4-factor model of psychopathy and hence, structural invariance, of PCL-R scores across ancestral groups. Structural equation modeling affirmed the predictive efficacy of the 4-factor model for recidivism. We discuss these findings in terms of clinical applications of the PCL-R and the psychopathy construct in general, with male offenders of indigenous ancestry. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

On the crucial importance of a small bird: The ecosystem services of the little auk (Alle alle) population in Northwest Greenland in a long-term perspective.

PubMed

Mosbech, Anders; Johansen, Kasper Lambert; Davidson, Thomas A; Appelt, Martin; Grønnow, Bjarne; Cuyler, Christine; Lyngs, Peter; Flora, Janne

2018-04-01

The little auk is the most numerous seabird in the North Atlantic and its most important breeding area is the eastern shores of the North Water polynya. Here, a population of an estimated 33 million pairs breeds in huge colonies and significantly shapes the ecosystem. Archaeological remains in the colonies document that the little auk has been harvested over millennia. Anthropological research discloses how the little auk has a role both as social engineer and as a significant resource for the Inughuit today. The hunting can be practiced without costly equipment, and has no gender and age discrimination in contrast to the dominant hunt for marine mammals. Little auks are ecological engineers in the sense that they transport vast amounts of nutrients from sea to land, where the nutrients are deposited as guano. Here, the fertilized vegetation provides important foraging opportunities for hares, geese, fox, reindeer, and the introduced muskox. We estimate that the relative muskox density is ten times higher within 1 km of little auk fertilized vegetation hotspots.

50 CFR 32.68 - West Virginia.

Code of Federal Regulations, 2010 CFR

2010-10-01

... ruffed grouse, squirrel, cottontail rabbit, snowshoe hare, red fox, gray fox, bobcat, woodchuck, coyote... overnight parking. D. Sport Fishing. [Reserved] Ohio River Islands National Wildlife Refuge A. Migratory... blinds. D. Sport Fishing. We allow sport fishing throughout the refuge in accordance with State...

Wind effects on the lateral motion of wake vortices

DOT National Transportation Integrated Search

1999-11-01

This report examines the influence of crosswind and other factors on the behavior of wake vortices between parallel runways. The measurements used in the analysis came from landing (1976-77) and takeoff (1980) operations at O'Hare International Airpo...

Report on FAA Deicing Program at La Guardia and O'Hare Airports

DOT National Transportation Integrated Search

1996-10-02

The Office of Inspector General, Department of Transportation; conducted a : followup inspection of the Federal Aviation Administration (FAA) Deicing : Program. We initiated this study to observe deicing operations as a followup to : our report on th...

40 CFR 180.582 - Pyraclostrobin; tolerances for residues.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 2.5 Gold of pleasure, seed 0.45 Grain, aspirated fractions 2.5 Grape 2.0 Grape, raisin 7.0 Grass, forage 10 Grass, hay 4.5 Grass, seed screenings 27 Grass, straw grown for seed 14 Hare's ear mustard...

Airport Surface Traffic Control Concept Formulation Study : Volume 1. Executive Summary.

DOT National Transportation Integrated Search

1975-07-01

The report describes the approach followed and the analysis techniques employed in the performance of the operations analysis of the current ASTC system for the baseline airport, O'Hare International Airport, Chicago, Illinois. It also describes the ...

Chicago monostatic acoustic vortex sensing system : Vol. IV. wake vortex decay

DOT National Transportation Integrated Search

1982-07-01

A Monostatic Acoustic Vortex Sensing System (MAVSS) was installed at Chicago's O'Hare International Airport to measure the strength and decay of aircraft wake vortices from landing aircraft. The MAVSS consists of an array of acoustic antennas which m...

Electronic intermodal supply chain manifest freight ITS operational test evaluation.

DOT National Transportation Integrated Search

2002-12-01

This report presents the results of a 2.5 year freight Intelligent Transportation System (ITS) evaluation of an air cargo security and logistics system which was deployed at O'Hare and JFK international airports. In September 1999, the Federal Highwa...

Associative Memory in Three Aplysiids: Correlation with Heterosynaptic Modulation

ERIC Educational Resources Information Center

Thompson, Laura; Wright, William G.; Hoover, Brian A.; Nguyen, Hoang

2006-01-01

Much recent research on mechanisms of learning and memory focuses on the role of heterosynaptic neuromodulatory signaling. Such neuromodulation appears to stabilize Hebbian synaptic changes underlying associative learning, thereby extending memory. Previous comparisons of three related sea-hares (Mollusca, Opisthobranchia) uncovered interspecific…

Seeing the Forest for the Trees: A Qualitative Synthesis Project.

ERIC Educational Resources Information Center

Beck, Cheryl Tatano

2003-01-01

Describes a project that required graduate nursing students to conduct qualitative meta-synthesis of ethnographic research, using Noblit and Hare's approach. Discusses the process of meta-synthesis, interpretation of outcomes, and students' reactions to the project. (Contains 16 references.) (SK)

Chicago Monostatic Acoustic Vortex Sensing System : Volume I. Data Collection and Reduction.

DOT National Transportation Integrated Search

1979-10-01

A Monostatic Acoustic Vortex Sensing System (MAVSS) was installed at Chicago's O'Hare International Airport to measure the strength and decay of aircraft wake vortices from landing aircraft. The MAVSS consists of an array of acoustic antennas which m...

The Child is Father to the Dog. Canines and Personality Processes in an Arctic Community

ERIC Educational Resources Information Center

Savishinsky, J. S.

1974-01-01

Suggests that persons concerned with personality formation might profit from an examination of the relationship between people and the domesticated animals they maintain. The Hare Indians in the Northwest Territories of Canada are discussed. (JMB)

"Is it still safe to eat traditional food?" Addressing traditional food safety concerns in aboriginal communities.

PubMed

Bordeleau, Serge; Asselin, Hugo; Mazerolle, Marc J; Imbeau, Louis

2016-09-15

Food insecurity is a growing concern for indigenous communities worldwide. While the risk of heavy metal contamination associated to wild food consumption has been extensively studied in the Arctic, data are scarce for the Boreal zone. This study addressed the concerns over possible heavy metal exposure through consumption of traditional food in four Anishnaabeg communities living in the Eastern North American boreal forest. Liver and meat samples were obtained from 196 snowshoe hares (Lepus americanus) trapped during winter 2012 across the traditional lands of the participating communities and within 56-156km of a copper smelter. Interviews were conducted with 78 household heads to assess traditional food habits, focusing on snowshoe hare consumption. Concentrations in most meat and liver samples were below the detection limit for As, Co, Cr, Ni and Pb. Very few meat samples had detectable Cd and Hg concentrations, but liver samples had mean dry weight concentrations of 3.79mg/kg and 0.15mg/kg respectively. Distance and orientation from the smelter did not explain the variability between samples, but percent deciduous and mixed forest cover had a marginal negative effect on liver Cd, Cu and Zn concentrations. The estimated exposition risk from snowshoe hare consumption was low, although heavy consumers could slightly exceed recommended Hg doses. In accordance with the holistic perspective commonly adopted by indigenous people, the nutritional and sociocultural importance of traditional food must be considered in risk assessment. Traditional food plays a significant role in reducing and preventing serious health issues disproportionately affecting First Nations, such as obesity, diabetes, and cardiovascular diseases. Copyright © 2016 Elsevier B.V. All rights reserved.

Computed tomography arthrography with traction in the human hip for three-dimensional reconstruction of cartilage and the acetabular labrum

PubMed Central

Henak, C.R.; Abraham, C.L.; Peters, C.L.; Sanders, R.K.; Weiss, J.A.; Anderson, A.E.

2014-01-01

AIM To develop and demonstrate the efficacy of a computed tomography arthrography (CTA) protocol for the hip that enables accurate three-dimensional reconstructions of cartilage and excellent visualization of the acetabular labrum. MATERIALS AND METHODS Ninety-three subjects were imaged (104 scans); 68 subjects with abnormal anatomy, 11 patients after periacetabular osteotomy surgery, and 25 subjects with normal anatomy. Fifteen to 25 ml of contrast agent diluted with lidocaine was injected using a lateral oblique approach. A Hare traction splint applied traction during CT. The association between traction force and intra-articular joint space was assessed qualitatively under fluoroscopy. Cartilage geometry was reconstructed from the CTA images for 30 subjects; the maximum joint space under traction was measured. RESULTS Using the Hare traction splint, the intra-articular space and boundaries of cartilage could be clearly delineated throughout the joint; the acetabular labrum was also visible. Dysplastic hips required less traction (~5 kg) than normal and retroverted hips required (>10 kg) to separate the cartilage. An increase in traction force produced a corresponding widening of the intra-articular joint space. Under traction, the maximum width of the intra-articular joint space during CT ranged from 0.98–6.7 mm (2.46 ± 1.16 mm). CONCLUSIONS When applied to subjects with normal and abnormal hip anatomy, the CTA protocol presented yields clear delineation of the cartilage and the acetabular labrum. Use of a Hare traction splint provides a simple, cost-effective method to widen the intra-articular joint space during CT, and provides flexibility to vary the traction as required. PMID:25070373

14 CFR 93.29 - International Arrival Authorizations.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false International Arrival Authorizations. 93.29... at Chicago O'Hare International Airport § 93.29 International Arrival Authorizations. (a) Except as... marketing arrangement unless the flight was predominately marketed, by contract, under the control of...

A multi-analytical approach for the characterization of wall painting materials on contemporary buildings

NASA Astrophysics Data System (ADS)

Magrini, Donata; Bracci, Susanna; Cantisani, Emma; Conti, Claudia; Rava, Antonio; Sansonetti, Antonio; Shank, Will; Colombini, MariaPerla

2017-02-01

Samples from Keith Haring's wall painting of the Necker Children Hospital in Paris were studied by a multi-analytical protocol. X-ray fluorescence (XRF), powder X-ray diffraction (XRDP), Electron microscope (SEM-EDS), Infrared and Raman spectroscopy (μ-FT-IR and μ-Raman) measurements were performed in order to characterize the materials and to identify the art technique used to produce this contemporary work. Materials from the mural suffered from severe detachments of materials and several fragments were found on the ground beneath. Some of these fragments, which were representative of the whole palette and stratigraphic sequence, were collected and studied. The fragments were sufficiently large to enable non-invasive measurements to be performed in order to characterize the materials. A comparison of the data of the techniques applied revealed that Haring's palette was composed of organic pigments such as Naphtol red, phthalocyanine blue and green and Hansa yellow, in accordance with those used previously by the artist in other painted murals.

Terminal Area Productivity Airport Wind Analysis and Chicago O'Hare Model Description

NASA Technical Reports Server (NTRS)

Hemm, Robert; Shapiro, Gerald

1998-01-01

This paper describes two results from a continuing effort to provide accurate cost-benefit analyses of the NASA Terminal Area Productivity (TAP) program technologies. Previous tasks have developed airport capacity and delay models and completed preliminary cost benefit estimates for TAP technologies at 10 U.S. airports. This task covers two improvements to the capacity and delay models. The first improvement is the completion of a detailed model set for the Chicago O'Hare (ORD) airport. Previous analyses used a more general model to estimate the benefits for ORD. This paper contains a description of the model details with results corresponding to current conditions. The second improvement is the development of specific wind speed and direction criteria for use in the delay models to predict when the Aircraft Vortex Spacing System (AVOSS) will allow use of reduced landing separations. This paper includes a description of the criteria and an estimate of AVOSS utility for 10 airports based on analysis of 35 years of weather data.

HARE: Supporting Efficient Uplink Multi-Hop Communications in Self-Organizing LPWANs.

PubMed

Adame Vázquez, Toni; Barrachina-Muñoz, Sergio; Bellalta, Boris; Bel, Albert

2018-01-03

The emergence of low-power wide area networks (LPWANs) as a new agent in the Internet of Things (IoT) will result in the incorporation into the digital world of low-automated processes from a wide variety of sectors. The single-hop conception of typical LPWAN deployments, though simple and robust, overlooks the self-organization capabilities of network devices, suffers from lack of scalability in crowded scenarios, and pays little attention to energy consumption. Aimed to take the most out of devices' capabilities, the HARE protocol stack is proposed in this paper as a new LPWAN technology flexible enough to adopt uplink multi-hop communications when proving energetically more efficient. In this way, results from a real testbed show energy savings of up to 15% when using a multi-hop approach while keeping the same network reliability. System's self-organizing capability and resilience have been also validated after performing numerous iterations of the association mechanism and deliberately switching off network devices.

HARE: Supporting Efficient Uplink Multi-Hop Communications in Self-Organizing LPWANs

PubMed Central

Barrachina-Muñoz, Sergio; Bellalta, Boris

2018-01-01

The emergence of low-power wide area networks (LPWANs) as a new agent in the Internet of Things (IoT) will result in the incorporation into the digital world of low-automated processes from a wide variety of sectors. The single-hop conception of typical LPWAN deployments, though simple and robust, overlooks the self-organization capabilities of network devices, suffers from lack of scalability in crowded scenarios, and pays little attention to energy consumption. Aimed to take the most out of devices’ capabilities, the HARE protocol stack is proposed in this paper as a new LPWAN technology flexible enough to adopt uplink multi-hop communications when proving energetically more efficient. In this way, results from a real testbed show energy savings of up to 15% when using a multi-hop approach while keeping the same network reliability. System’s self-organizing capability and resilience have been also validated after performing numerous iterations of the association mechanism and deliberately switching off network devices. PMID:29301351

Electronic intermodal supply chain manifest ITS field operational test evaluation plan

DOT National Transportation Integrated Search

2000-09-25

This document is an evaluation plan for a field operational test (FOT) that is based at O'Hare International Airport in Chicago and which will focus on the air cargo component of intermodal freight movements. The objectives of the FOT are to develop,...

50 CFR 32.68 - West Virginia.

Code of Federal Regulations, 2013 CFR

2013-10-01

... rabbit, snowshoe hare, red fox, gray fox, bobcat, woodchuck, coyote, opossum, striped skunk, and raccoon... season. The gun bear season begins the Monday following the antlerless deer season. D. Sport Fishing..., chest, and back while walking to and from tree stands or blinds. D. Sport Fishing. We allow sport...

50 CFR 32.68 - West Virginia.

Code of Federal Regulations, 2011 CFR

2011-10-01

..., cottontail rabbit, snowshoe hare, red fox, gray fox, bobcat, woodchuck, coyote, opossum, striped skunk, and.... Sport Fishing. [Reserved] Ohio River Islands National Wildlife Refuge A. Migratory Game Bird Hunting. We..., chest, and back while walking to and from tree stands or blinds. D. Sport Fishing. We allow sport...

50 CFR 32.68 - West Virginia.

Code of Federal Regulations, 2014 CFR

2014-10-01

... rabbit, snowshoe hare, red fox, gray fox, bobcat, woodchuck, coyote, opossum, striped skunk, and raccoon... season. The gun bear season begins the Monday following the antlerless deer season. D. Sport Fishing..., chest, and back while walking to and from tree stands or blinds. D. Sport Fishing. We allow sport...

50 CFR 32.68 - West Virginia.

Code of Federal Regulations, 2012 CFR

2012-10-01

... rabbit, snowshoe hare, red fox, gray fox, bobcat, woodchuck, coyote, opossum, striped skunk, and raccoon... season. The gun bear season begins the Monday following the antlerless deer season. D. Sport Fishing..., chest, and back while walking to and from tree stands or blinds. D. Sport Fishing. We allow sport...

U.S. EPA, Pesticide Product Label, , 05/08/1989

EPA Pesticide Factsheets

2011-04-21

... "'hare po •• 1bl •. ... ":" •• S 5?:-!:e":" n .. a=~. ;a:: .. r~~a .~~ ~. r, c~a:-g .. ra. ... Cont.et :rour !tate 'aatlelde or I:nel ron.ent.l Con:ro~ A9an:::T or Ha ...

Chicago Monostatic Acoustic Vortex Sensing System : Vol. II. Decay of B-707 and DC-8 Vortices.

DOT National Transportation Integrated Search

1981-09-01

A Monostatic Acoustic Vortex Sensing System (MAVSS) was installed at Chicago's O'Hare International Airport to measure the strength and decay of aircraft wake vortices from landing aircraft. The MAVSS consists of an array of acoustic antennas which m...

The tortoise and the hare: Reducing resource availability shifts competitive balance between plant species

Treesearch

Dean E. Pearson; Yvette K. Ortega; John L. Maron

2017-01-01

Determining how changes in abiotic conditions influence community interactions is a fundamental challenge in ecology. Meeting this challenge is increasingly imperative in the Anthropocene where climate change and exotic species introductions alter abiotic context and biotic composition to reshuffle natural systems.

Effect of fuels reduction on American martens and their prey.

Treesearch

Evelyn L. Bull; Arlene K. Blumton

1999-01-01

The effect of a fuels reduction treatment on small mammals was investigated in lodgepole pine (Pinus contorta) and mixed conifer stands by trapping and track surveys in northeastern Oregon. The number of red squirrel (Tamiasciurus hudsonicus) and snowshoe hare (Lepus americanus) tracks decreased in all...

The use of radio telemetry in Martes research: techniques and technologies

Treesearch

Craig M. Thompson; Rebecca A. Green; Joel Sauder; Kathryn L. Purcell; Richard Sweitzer; Jon Armeno

2012-01-01

Radiotelemetry was fi rst used on a Martes species in 1972, when 5 American martens ( Martes americana ) captured incidentally during a snowshoe hare ( Lepus americanus ) research project in Minnesota were radio-collared. Since then, at least 128 research projects have used radiotelemetry to investigate...

Measurement of the ATCRBS Surface Interrogation Environments at Chicago O'Hare and Los Angeles International Airports

DOT National Transportation Integrated Search

1976-07-01

The Transportation Systems Center is conducting a progrm to develop a surface surveillance sensor that uses replies from ATCRBS tansponders. The operation of this system can be affected by surface interrogations at major airports where such a system ...

Chicago Monostatic Acoustic Vortex Sensing System : Vol. III. Decay of B-707 and DC-8 Vortices. Executive Summary

DOT National Transportation Integrated Search

1982-01-01

A Monostatic Acoustic Vortex Sensing System (MAVSS) was installed at Chicago's O'Hare International Airport to measure the strength and decay of aircraft wake vortices from landing aircraft. The MAVSS consists of an array of acoustic antennas which m...

U.S. EPA, Pesticide Product Label, , 01/06/1983

EPA Pesticide Factsheets

2011-04-21

... nO ron! ... I. ' ... r .htr r .. ~t'oI-dn~ lilt" Ht:T~S.-\\~ ttt"'lfti ... O-\\:;:I&If' r .. M'....L~ to-_'nt"r Il':.n" mOfllh, al\\o;-r lit 1 \\---\\ i'I'." Ill.· n 'I'l.i~ r~ ... df'r .. d ..... j (hare-, .. ...

The Tortoise and the Hare: Less Jogging, More Sprints and Marathons.

ERIC Educational Resources Information Center

Ginsburg, Sigmund G.

1992-01-01

To cope with changing financial and demographic environments, colleges are encouraged to change management strategies. Suggestions are made for policy formation and improved use of human and material resources in the areas of fiscal management, student recruitment, staffing, campus management, academic programing, and links with business,…

Simple Numerical Analysis of Longboard Speedometer Data

ERIC Educational Resources Information Center

Hare, Jonathan

2013-01-01

Simple numerical data analysis is described, using a standard spreadsheet program, to determine distance, velocity (speed) and acceleration from voltage data generated by a skateboard/longboard speedometer (Hare 2012 "Phys. Educ." 47 409-17). This simple analysis is an introduction to data processing including scaling data as well as…

Animal damage to birch

Treesearch

James S. Jordan; Francis M. Rushmore

1969-01-01

A relatively few animal species are responsible for most of the reported damage to the birches. White-tailed deer, yellow-bellied sapsuckers, porcupines, moose, and hares are the major animals involved. We will review reports of damage, discuss the underlying causes, and describe possible methods of control. For example, heavy deer browsing that eliminates birch...

DIETARY NITROGEN AVAILABILITY IN MACROALGAE AFFECTS GROWTH OF THE SEA HARE APLYSIA CALIFORNICA (OPISTHOBRANCHIA:ANASPIDEA). (R830414)

EPA Science Inventory

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

Effects of Inundation on Six Varieties of Turfgrass.

DTIC Science & Technology

1982-05-01

biosyn- thesis of lignin and flavonoids . Annual Review of Plant Physiology, vol. 30, p. 105-130. Hare, R.C. (1964) Indoleacetic acid oxidase...southern great plains. Journal of the American Society of Agronomy, voi. 33, p. 125-129. L t23 Ponnamperuma, F.N. (1972) The chemistry of submerged

American Involvement in Fringe Religious Cults

ERIC Educational Resources Information Center

Intellect, 1977

1977-01-01

"Twenty million Americans are involved in fringe religious cults such as spiritualism, Hare Krishna, Scientology, and Black Gospel groups," according to anthropologist Irving Zaretsky of the University of Chicago. He recently completed a 10-year period as a participant-observer of fringe religious groups in the San Francisco Bay area and the…

Identifying Psychopathy Subtypes on the Basis of Personality Structure

ERIC Educational Resources Information Center

Hicks, Brian M.; Markon, Kristian E.; Patrick, Christopher J.; Krueger, Robert F.; Newman, Joseph P.

2004-01-01

The authors used model-based cluster analysis to identify subtypes of criminal psychopaths on the basis of differences in personality structure. Participants included 96 male prisoners diagnosed as psychopathic, using the Psychopathy Checklist Revised (PCL-R; R. D. Hare, 1991). Personality was assessed using the brief form of the Multidimensional…

Experimental and spontaneous clostridial enteropathies of laboratory and free living lagomorphs.

PubMed

Carman, R J; Evans, R H

1984-10-01

The enteric diseases of hares, European and cottontail rabbits, which are caused by members of the genus Clostridium are reviewed. Disease caused by C. perfringens Types A and E, C. spiroforme, C. difficile, C. sordellii, C. tympany cuniculi and clostridial enterotoxins are included. Tyzzer's disease also is discussed.

Reliable Internet Routing

DTIC Science & Technology

2011-09-01

global coordination. IEEE/ACM Trans. Netw., 9(6):681–692, 2001. [39] S. Goldberg, D. Xiao, E. Tromer, B. Barak , and J. Rexford. Path-quality monitoring...RFC 4271). [81] Y. Rekhter, T. Li, and S. Hares. A border gateway protocol 4 (BGP-4), 2006. IETF RFC 4271. [82] E. Rosen , A. Viswanathan, and R. Callon

77 FR 3585 - Airworthiness Directives; Cirrus Design Corporation Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-25

..., O'Hare Lake Office Center, 2300 East Devon Ave., Des Plaines, Illinois 60018; phone: (847) 294-7870... under warranty, thereby reducing the cost impact on affected individuals. We do not control warranty...: (1) Group 1 Airplanes: Cirrus Design Corporation Model SR22T airplanes, serial numbers 0001 through...

Regularized Semiparametric Estimation for Ordinary Differential Equations

PubMed Central

Li, Yun; Zhu, Ji; Wang, Naisyin

2015-01-01

Ordinary differential equations (ODEs) are widely used in modeling dynamic systems and have ample applications in the fields of physics, engineering, economics and biological sciences. The ODE parameters often possess physiological meanings and can help scientists gain better understanding of the system. One key interest is thus to well estimate these parameters. Ideally, constant parameters are preferred due to their easy interpretation. In reality, however, constant parameters can be too restrictive such that even after incorporating error terms, there could still be unknown sources of disturbance that lead to poor agreement between observed data and the estimated ODE system. In this paper, we address this issue and accommodate short-term interferences by allowing parameters to vary with time. We propose a new regularized estimation procedure on the time-varying parameters of an ODE system so that these parameters could change with time during transitions but remain constants within stable stages. We found, through simulation studies, that the proposed method performs well and tends to have less variation in comparison to the non-regularized approach. On the theoretical front, we derive finite-sample estimation error bounds for the proposed method. Applications of the proposed method to modeling the hare-lynx relationship and the measles incidence dynamic in Ontario, Canada lead to satisfactory and meaningful results. PMID:26392639

Impact of rewilding, species introductions and climate change on the structure and function of the Yukon boreal forest ecosystem.

PubMed

Boonstra, Rudy; Boutin, Stan; Jung, Thomas S; Krebs, Charles J; Taylor, Shawn

2018-03-01

Community and ecosystem changes are happening in the pristine boreal forest ecosystem of the Yukon for 2 reasons. First, climate change is affecting the abiotic environment (temperature, rainfall and growing season) and driving changes in plant productivity and predator-prey interactions. Second, simultaneously change is occurring because of mammal species reintroductions and rewilding. The key ecological question is the impact these faunal changes will have on trophic dynamics. Primary productivity in the boreal forest is increasing because of climatic warming, but plant species composition is unlikely to change significantly during the next 50-100 years. The 9-10-year population cycle of snowshoe hares will persist but could be reduced in amplitude if winter weather increases predator hunting efficiency. Small rodents have increased in abundance because of increased vegetation growth. Arctic ground squirrels have disappeared from the forest because of increased predator hunting efficiency associated with shrub growth. Reintroductions have occurred for 2 reasons: human reintroductions of large ungulates and natural recolonization of mammals and birds extending their geographic ranges. The deliberate rewilding of wood bison (Bison bison) and elk (Cervus canadensis) has changed the trophic structure of this boreal ecosystem very little. The natural range expansion of mountain lions (Puma concolor), mule deer (Odocoileus hemionus) and American marten (Martes americana) should have few ecosystem effects. Understanding potential changes will require long-term monitoring studies and experiments on a scale we rarely deem possible. Ecosystems affected by climate change, species reintroductions and human alteration of habitats cannot remain stable and changes will be critically dependent on food web interactions. © 2017 The Authors. Integrative Zoology published by International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

Reliability Generalization of the Psychopathy Checklist Applied in Youthful Samples

ERIC Educational Resources Information Center

Campbell, Justin S.; Pulos, Steven; Hogan, Mike; Murry, Francie

2005-01-01

This study examines the average reliability of Hare Psychopathy Checklists (PCLs) adapted for use in samples of youthful offenders (aged 12 to 21 years). Two forms of reliability are examined: 18 alpha estimates of internal consistency and 18 intraclass correlation (two or more raters) estimates of interrater reliability. The results, an average…

Biogeochemistry of aragonite mud and oolites.

NASA Technical Reports Server (NTRS)

Mitterer, R. M.

1972-01-01

Amino acids were determined on an analyzer similar to that described by Hare (1969) in carbonate mud samples from locations in the Bahamas, Bermuda, Persian Gulf, and Florida Bay, and in oolites from the Gulf of Suez, the Abu Dhabi coast, the Bahamas, and Baffin Bay, Texas. A histogram, tables, and chromatograms of the results are given.

The Hare and the Tortoise: Emphasizing Speed Can Change the Evidence Used to Make Decisions

ERIC Educational Resources Information Center

Rae, Babette; Heathcote, Andrew; Donkin, Chris; Averell, Lee; Brown, Scott

2014-01-01

Decision-makers effortlessly balance the need for urgency against the need for caution. Theoretical and neurophysiological accounts have explained this tradeoff solely in terms of the "quantity" of evidence required to trigger a decision (the "threshold"). This explanation has also been used as a benchmark test for evaluating…

Gene expression results

EPA Pesticide Factsheets

qPCR results for VitellogeninThis dataset is associated with the following publication:Armstrong, B., J. Lazorchak , K. Jensen , H. Haring , M.E. Smith, R. Flick , D. Bencic , and A. Biales. Reproductive effects in fathead minnows (Pimphales promelas) following a 21 d exposure to 17α-ethinylestradiol. CHEMOSPHERE. Elsevier Science Ltd, New York, NY, USA, 144(1): 366-373, (2015).

Open-Mindedness and Intellectual Humility

ERIC Educational Resources Information Center

Spiegel, James S.

2012-01-01

Among those who regard open-mindedness as a virtue, there is dispute over whether the trait is essentially an attitude toward particular beliefs or toward oneself as a believer. I defend William Hare's account of open-mindedness as a first-order attitude toward one's beliefs and critique Peter Gardner's view of open-mindedness as a non-commital…

14 CFR Special Federal Aviation... - Operating Limitations for Unscheduled Operations at Chicago's O'Hare International Airport

Code of Federal Regulations, 2010 CFR

2010-01-01

.... Hurley Air Traffic Control System Command Center. It is responsible for the administration of... 6). “Enhanced Computer Voice Reservation System (e-CVRS)” is the system used by the FAA to make... charter flights; hired aircraft service; ferry flights; and other non-passenger flights. Section 3...

Mad Tea Party Cyclic Partitions

ERIC Educational Resources Information Center

Bekes, Robert; Pedersen, Jean; Shao, Bin

2012-01-01

Martin Gardner's "The Annotated Alice," and Robin Wilson's "Lewis Carroll in Numberland" led the authors to put this article in a fantasy setting. Alice, the March Hare, the Hatter, and the Dormouse describe a straightforward, elementary algorithm for counting the number of ways to fit "n" identical objects into "k" cups arranged in a circle. The…

Bridging the Hemispheres through the Use of Technology: International Collaboration in Social Work Training

ERIC Educational Resources Information Center

Rautenbach, John Victor; Black-Hughes, Christine

2012-01-01

The social work programs of the University of Fort Hare, East London, South Africa, and Minnesota State University, Mankato, United States, began using various technologies in 2007 to facilitate interaction. This project included conducting practicum supervision and seminars via videoconferencing (using Breeze, Adobe Connect, and Skype) and…

[Report of Micipsella numidica (Seurat, 1917) in Italy].

PubMed

Cancrini, G; Poglayen, G; Vecchi, G

1988-01-01

The first record in Italy of Micipsella numidica (Seurat, 1917) is reported. The parasite was collected from the portal vein of two rabbits (Oryctolagus cuniculus). Morphological features of the worms (4 females, 3 males and microfilariae from uterus) are described and compared with those reported for African, European and Asiatic specimens found in hares.

A gray wolf (Canis lupus) delivers live prey to a pup

USGS Publications Warehouse

Mech, L. David

2014-01-01

A two-year-old sibling Gray Wolf (Canis lupus) carefully captured an Arctic Hare (Lepus arcticus) leveret alive on Ellesmere Island, Nunavut, Canada, and delivered it alive to a pup 28–33 days old. This appears to be the first observation of a Gray Wolf delivering live prey to a pup.

Psychopathy and Violence: The Importance of Factor Level Interactions

ERIC Educational Resources Information Center

Walsh, Zach; Kosson, David S.

2008-01-01

The power of scales based on the Psychopathy Checklist (PCL; R. D. Hare, 1980) for prediction of violent behavior is well established. Although evidence suggests that this relationship is chiefly due to the impulsive and antisocial lifestyle component (Factor 2), the predictive power of psychopathy for violence may also reflect the multiplicative…

75 FR 8193 - Jeri Hassman, M.D.; Denial of Application

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-23

..., Respondent maintained that there is nothing wrong with persons using a controlled substance that has not been... the patient as to whether he is using the medication appropriately.\\13\\ Id. The physician should... pain agreements and were not using them. Tr. 1012-13. Dr. Hare, however, testified that the agreements...

14 CFR 93.218 - Slots for transborder service to and from Canada.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Canada. 93.218 Section 93.218 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... service to and from Canada. (a) Except as otherwise provided in this subpart, international slots...'Hare in the Winter season. (c) Any modification to the slot base by the Government of Canada or the...

PCL-R Psychopathy Predicts Disruptive Behavior Among Male Offenders in a Dutch Forensic Psychiatric Hospital

ERIC Educational Resources Information Center

Hildebrand, Martin; De Ruiter, Corine; Nijman, Henk

2004-01-01

In this study, the relationship between psychopathy, according to the Dutch language version of Hare's Psychopathy Checklist-Revised (PCL-R), and various types of disruptive behavior during inpatient forensic psychiatric treatment is investigated. Ninety-two male participants were administered the PCL-R following admission to an inpatient forensic…

Field Validity of the Psychopathy Checklist--Revised in Sex Offender Risk Assessment

ERIC Educational Resources Information Center

Murrie, Daniel C.; Boccaccini, Marcus T.; Caperton, Jennifer; Rufino, Katrina

2012-01-01

Several studies have concluded that scores from Hare's (2003) Psychopathy Checklist--Revised (PCL-R) predict reoffense among sexual offenders, but most of those studies examined the predictive validity of scores from trained research staff, not clinicians in the field scoring the measure as part of actual forensic assessments. Therefore, we…

The Tortoise and the Hare Enigma in E-Transformation in Japanese and Korean Higher Education

ERIC Educational Resources Information Center

Latchem, Colin; Jung, Insung; Aoki, Kumiko; Ozkul, Ali Ekrem

2008-01-01

Japan and Korea have highly developed information and communications technology infrastructures and have recently reformed their higher education systems and encouraged e-transformation. However, Japanese universities have not embraced e-learning as wholeheartedly as their Korean counterparts. The paper concludes that this is due to governmental…

Benefits of Job Clubs for Executive Job Seekers: A Tale of Hares and Tortoises

ERIC Educational Resources Information Center

Kondo, Christopher T.

2009-01-01

This qualitative research study compares the experiences of 2 groups of executive job seekers--job club members and nonmembers--through thematic analysis of open-ended interviews. The findings indicated that job club members benefited from group learning, increased accountability, networking opportunities, emotional support, helping other members,…

Use of the sea hare (Aplysia fasciata) in marine pollution biomonitoring of harbors and bays.

PubMed

Dirrigl, Frank J; Badaoui, Zachariah; Tamez, Carlos; Vitek, Christopher J; Parsons, Jason G

2018-04-01

Our study evaluated heavy metal concentrations in soft tissues of sea hare, Aplysia fasciata, from the Lower Laguna Madre, Texas. Heavy metals in tissues followed Se>As>Pb>Cd. Concentrations ranged As (BDL-28.08), Cd (BDL-5.50), Pb (BDL-12.85) and Se (4.25-93.43ppm). Median As, Cd, Pb, and Se tissue levels exceeded exposure levels. Significant relationships occurred in metal-metal (AsCd, AsPb, CdPb, CdSe, and PbSe), metal-tissue (significant Se uptake by inhalant and exhalant siphons and As in the hepatopancreas), and metal-metal within tissue (AsPb in the hepatopancreas and CdPb in the digestive cecum) analyses (p<0.05). Bioaccumulation factors (BAF) suggested the inhalant siphon, hepatopancreas, and digestive cecum function as macroconcentrators of Cd, hepatopancreas and digestive cecum as macroconcentrators of Pb, and all tissues were deconcentrators for As and Se. As a bioaccumulator of heavy metals, Aplysia was evaluated as a bioindicator of marine pollution in harbors and bays. Copyright © 2017 Elsevier Ltd. All rights reserved.

Lesions of Copper Toxicosis in Captive Marine Invertebrates With Comparisons to Normal Histology.

PubMed

LaDouceur, E E B; Wynne, J; Garner, M M; Nyaoke, A; Keel, M K

2016-05-01

Despite increasing concern for coral reef ecosystem health within the last decade, there is scant literature concerning the histopathology of diseases affecting the major constituents of coral reef ecosystems, particularly marine invertebrates. This study describes histologic findings in 6 species of marine invertebrates (California sea hare [Aplysia californica], purple sea urchin [Strongylocentrotus purpuratus], sunburst anemone [Anthopleura sola], knobby star [Pisaster giganteus], bat star [Asterina miniata], and brittle star [Ophiopteris papillosa]) with spontaneous copper toxicosis, 4 purple sea urchins with experimentally induced copper toxicosis, and 1 unexposed control of each species listed. The primary lesions in the California sea hare with copper toxicosis were branchial and nephridial necrosis. Affected echinoderms shared several histologic lesions, including epidermal necrosis and ulceration and increased numbers of coelomocytes within the water-vascular system. The sunburst anemone with copper toxicosis had necrosis of both epidermis and gastrodermis, as well as expulsion of zooxanthellae from the gastrodermis. In addition to the lesions attributed to copper toxicosis, our results describe normal microscopic features of these animals that may be useful for histopathologic assessment of marine invertebrates. © The Author(s) 2015.

Molecular and phylogenetic analysis of the filarial nematode Micipsella numidica from the hare Lepus europaeus in Italy.

PubMed

Gabrielli, S; Galuppi, R; Fraulo, M; Savini, F; Morandi, B; Cancrini, G; Poglayen, G

2016-07-01

The genus Micipsella comprises three species of filariae to date identified in lagomorphs only, whereas the other genera belonging to the subfamily Splendidofilariinae are described as parasites of birds, reptiles and mammals. In the present study seven specimens of Micipsella numidica (Seurat, 1917), collected from the hare Lepus europaeus in Italy, were characterized genetically by molecular amplification of the mitochondrial genes (12S rDNA; cox1) and the 5S rDNA gene spacer region. Phylogenetic trees inferred using available sequences from filariae and those identified in this study evidenced a close relationship between M. numidica and Splendidofilariinae of other mammals and reptiles (Rumenfilaria andersoni and Madathamugadia hiepei). The present findings, apart from adding new data about the hosts in Italy, support the taxonomic position of M. numidica and highlight the substantial biological and molecular differences existing between Splendidofilariinae and other Onchocercidae. The study also contributes to our knowledge of the molecular/genetic diagnosis of filarial parasites of veterinary and medical concern in any vertebrate or invertebrate host.

[Is Sexual Identity Optional? A Study of The Genetics of Transsexuality].

PubMed

Fernández García, Rosa M; Pásaro Méndez, Eduardo

2017-01-01

Transsexualism in the ICD-10 (International Classification of Diseases, Tenth Revision), Gender Dysphoria in adolescents and adults in the DSM-5 (Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition), is characterized by a marked incongruence between one's experienced gender and biological sex. The etiology is complex, but some hypotheses suggest that Gender Dysphoria (GD) arises from discrepant cerebral and biological sexual differentiation. Increasing evidence supports the idea of genetic vulnerability. Henningsson et al, (2004) found significant differences when they examined estrogen receptor β (ERβ) in a male-to- female (MtF) population. They suggested that a long ERβ polymorphism is more common in MtFs. Hare et al, (2009) also examined an MtF population and found a significant association between the androgen receptor (AR) and GD. Our group analyzed the same polymorphisms and found an association between ERα, ERβ and AR in GD. Our results suggest a genetic basis of GD in MtF and FtM populations. Our data corroborate the implication of the two estrogen receptors, ERα and β, and the androgen receptor in the genetic basis of GD, and advise the importance of estrogens and androgens in cerebral masculinization. Our data also confirm that sexual identity is not optional, but is determined prenatally by the genes, although it has a very important hormonal component. Therefore, its substrate is cerebral, not ideological.

Comprehensive enzymatic analysis of the amylolytic system in the digestive fluid of the sea hare, Aplysia kurodai: Unique properties of two α-amylases and two α-glucosidases.

PubMed

Tsuji, Akihiko; Nishiyama, Nami; Ohshima, Miki; Maniwa, Saori; Kuwamura, Shuji; Shiraishi, Masataka; Yuasa, Keizo

2014-01-01

Sea lettuce (Ulva pertusa) is a nuisance species of green algae that is found all over the world. East-Asian species of the marine gastropod, the sea hare Aplysia kurodai, shows a clear feeding preference for sea lettuce. Compared with cellulose, sea lettuce contains a higher amount of starch as a storage polysaccharide. However, the entire amylolytic system in the digestive fluid of A. kurodai has not been studied in detail. We purified α-amylases and α-glucosidases from the digestive fluid of A. kurodai and investigated the synergistic action of these enzymes on sea lettuce. A. kurodai contain two α-amylases (59 and 80 kDa) and two α-glucosidases (74 and 86 kDa). The 59-kDa α-amylase, but not the 80-kDa α-amylase, was markedly activated by Ca(2+) or Cl(-). Both α-amylases degraded starch and maltoheptaose, producing maltotriose, maltose, and glucose. Glucose production from starch was higher with 80-kDa α-amylase than with 59-kDa α-amylase. Kinetic analysis indicated that 74-kDa α-glucosidase prefers short α-1,4-linked oligosaccharide, whereas 86-kDa α-glucosidase prefers large α-1,6 and α-1,4-linked polysaccharides such as glycogen. When sea lettuce was used as a substrate, a 2-fold greater amount of glucose was released by treatment with 59-kDa α-amylase and 74-kDa α-glucosidase than by treatment with 45-kDa cellulase and 210-kDa β-glucosidase of A. kurodai. Unlike mammals, sea hares efficiently digest sea lettuce to glucose by a combination of two α-amylases and two α-glucosidases in the digestive fluids without membrane-bound maltase-glucoamylase and sucrase-isomaltase complexes.

Comprehensive enzymatic analysis of the amylolytic system in the digestive fluid of the sea hare, Aplysia kurodai: Unique properties of two α-amylases and two α-glucosidases

PubMed Central

Tsuji, Akihiko; Nishiyama, Nami; Ohshima, Miki; Maniwa, Saori; Kuwamura, Shuji; Shiraishi, Masataka; Yuasa, Keizo

2014-01-01

Sea lettuce (Ulva pertusa) is a nuisance species of green algae that is found all over the world. East-Asian species of the marine gastropod, the sea hare Aplysia kurodai, shows a clear feeding preference for sea lettuce. Compared with cellulose, sea lettuce contains a higher amount of starch as a storage polysaccharide. However, the entire amylolytic system in the digestive fluid of A. kurodai has not been studied in detail. We purified α-amylases and α-glucosidases from the digestive fluid of A. kurodai and investigated the synergistic action of these enzymes on sea lettuce. A. kurodai contain two α-amylases (59 and 80 kDa) and two α-glucosidases (74 and 86 kDa). The 59-kDa α-amylase, but not the 80-kDa α-amylase, was markedly activated by Ca2+ or Cl−. Both α-amylases degraded starch and maltoheptaose, producing maltotriose, maltose, and glucose. Glucose production from starch was higher with 80-kDa α-amylase than with 59-kDa α-amylase. Kinetic analysis indicated that 74-kDa α-glucosidase prefers short α-1,4-linked oligosaccharide, whereas 86-kDa α-glucosidase prefers large α-1,6 and α-1,4-linked polysaccharides such as glycogen. When sea lettuce was used as a substrate, a 2-fold greater amount of glucose was released by treatment with 59-kDa α-amylase and 74-kDa α-glucosidase than by treatment with 45-kDa cellulase and 210-kDa β-glucosidase of A. kurodai. Unlike mammals, sea hares efficiently digest sea lettuce to glucose by a combination of two α-amylases and two α-glucosidases in the digestive fluids without membrane-bound maltase–glucoamylase and sucrase–isomaltase complexes. PMID:25161866

Sedimentology, CSFe relationships and stable isotopic compositions in Devonian black mudrocks, Mackenzie Mountains, Northwest Territories, Canada

NASA Astrophysics Data System (ADS)

Al-Aasm, I. S.; Morad, S.; Durocher, S.; Muir, I.

1996-11-01

An integrated approach combining CSFe relationships, stable isotopic compositions, and lithofacies characterization was utilized to constrain the palaeoenvironmental and early diagenetic conditions of Middle-Upper Devonian (Eifelian-Frasnian) mudrocks from the Mackenzie Mountains, Northwest Territories, Canada. These rocks include the Hare Indian Formation (informally subdivided into the lower Bluefish Member and the Hare Indian Upper Member), Carcajou Marker and Canol Formation. The Bluefish Member is dominated by black, laminated, organic-rich shales (TOC = 0.35-10.34 wt.%; av. 5.83 wt.) with moderate degrees of pyritization (DOP) of 0.34-0.67 (av. 0.55). These mudrocks were deposited in dysoxic marine bottom-waters that became progressively more oxygenated with time. Variations in TOC, DOP and organic matter δ 13C PDB values (-29.7% to -19.9%; av. -27.2%) are attributed to repeated clastic dilution and increased input of terrestrial organic matter in association with shallowing-upward ramp-clinothem cycles. Pyrite δ 34S CDT values (-32.7% to -18.8%; av. -24.9%) indicate an open system, bacteriogenic seawater-sulphate reduction. Conversely, the overlying Hare Indian Upper Member, characterized by clinothem facies, is composed of grey to green mudstone with minor argillaceous limestones and considerably less organic matter contents (TOC = 0.28-2.99 wt.%; δ 13C = -29.5% to -22.5%). Deposition occurred in oxic to slightly dysoxic waters (DOP = 0.20-0.54; δ 34S = -23.0% to -20.9%), depending on the palaeotopographic location along the depositional slope. A rapid rise in sea level drowned the carbonate 'ramp' member of the Ramparts Formation and produced the thin, organic-rich Carcajou Marker. Bottom-water stagnation that resulted from subdued ramp palaeotopography produced anoxic sea bottom. Black, laminated, organic-rich shales from the Canol Formation (TOC = 1.37-6.68 wt.%) are very similar to those of the Bluefish Member, and are likewise basinal sediments. However, TOC, DOP and organic-matter δ 13C PDB values (-29.1% to -20.8%; av. -26.2%) do not show pronounced variations and indicate that low-energy, quietwater conditions persisted over relatively long, uninterrupted periods of time. High DOP values (0.72-0.93) throughout the Canol Formation suggest that deposition occurred in anoxic bottom-waters, but as basin-fill conditions continued there was a shift to a dysoxic environment (DOP = 0.55-0.65), which grades into nearshore and offshore sequences of the overlying Imperial Formation. In contrast with the Hare Indian Formation, much heavier δ 34S CDT values of pyrite in Canol mudrocks (-11.1% to +5.3%; av. -3.1%) point to bacterial sulphate reduction in a closed to semi-closed system with respect to seawater sulphate.

SpaceInn hare-and-hounds exercise: Estimation of stellar properties using space-based asteroseismic data

NASA Astrophysics Data System (ADS)

Reese, D. R.; Chaplin, W. J.; Davies, G. R.; Miglio, A.; Antia, H. M.; Ball, W. H.; Basu, S.; Buldgen, G.; Christensen-Dalsgaard, J.; Coelho, H. R.; Hekker, S.; Houdek, G.; Lebreton, Y.; Mazumdar, A.; Metcalfe, T. S.; Silva Aguirre, V.; Stello, D.; Verma, K.

2016-07-01

Context. Detailed oscillation spectra comprising individual frequencies for numerous solar-type stars and red giants are either currently available, e.g. courtesy of the CoRoT, Kepler, and K2 missions, or will become available with the upcoming NASA TESS and ESA PLATO 2.0 missions. The data can lead to a precise characterisation of these stars thereby improving our understanding of stellar evolution, exoplanetary systems, and the history of our galaxy. Aims: Our goal is to test and compare different methods for obtaining stellar properties from oscillation frequencies and spectroscopic constraints. Specifically, we would like to evaluate the accuracy of the results and reliability of the associated error bars, and to see where there is room for improvement. Methods: In the context of the SpaceInn network, we carried out a hare-and-hounds exercise in which one group, the hares, simulated observations of oscillation spectra for a set of ten artificial solar-type stars, and a number of hounds applied various methods for characterising these stars based on the data produced by the hares. Most of the hounds fell into two main groups. The first group used forward modelling (I.e. applied various search/optimisation algorithms in a stellar parameter space) whereas the second group relied on acoustic glitch signatures. Results: Results based on the forward modelling approach were accurate to 1.5% (radius), 3.9% (mass), 23% (age), 1.5% (surface gravity), and 1.8% (mean density), as based on the root mean square difference. Individual hounds reached different degrees of accuracy, some of which were substantially better than the above average values. For the two 1M⊙ stellar targets, the accuracy on the age is better than 10% thereby satisfying the requirements for the PLATO 2.0 mission. High stellar masses and atomic diffusion (which in our models does not include the effects of radiative accelerations) proved to be sources of difficulty. The average accuracies for the acoustic radii of the base of the convection zone, the He II ionisation, and the Γ1 peak located between the two He ionisation zones were 17%, 2.4%, and 1.9%, respectively. The results from the forward modelling were on average more accurate than those from the glitch fitting analysis as the latter seemed to be affected by aliasing problems for some of the targets. Conclusions: Our study indicates that forward modelling is the most accurate way of interpreting the pulsation spectra of solar-type stars. However, given its model-dependent nature, this method needs to be complemented by model-independent results from, e.g. glitch analysis. Furthermore, our results indicate that global rather than local optimisation algorithms should be used in order to obtain robust error bars.

Bovine Tuberculosis (Mycobacterium bovis) in Wildlife in Spain

PubMed Central

Aranaz, Alicia; de Juan, Lucía; Montero, Natalia; Sánchez, Celia; Galka, Margarita; Delso, Consuelo; Álvarez, Julio; Romero, Beatriz; Bezos, Javier; Vela, Ana I.; Briones, Victor; Mateos, Ana; Domínguez, Lucas

2004-01-01

Mycobacterium bovis infection in wildlife and feral species is a potential source of infection for livestock and a threat to protected and endangered species. The aim of this study was to identify Spanish wild animal species infected with M. bovis through bacteriological culture and spacer oligonucleotide typing (spoligotyping) of isolates for epidemiological purposes. This study included samples from red deer (Cervus elaphus), fallow deer (Dama dama), wild boar (Sus scrofa), Iberian lynx (Lynx pardina), hare (Lepus europaeus), and cattle (Bos taurus). They were collected in several geographical areas that were selected for their unique ecological value and/or known relationships between wildlife and livestock. In the areas included in this survey, M. bovis strains with the same spoligotyping pattern were found infecting several wild species and livestock, which indicates an epidemiological link. A locally predominant spoligotype was found in these areas. Better understanding of the transmission and distribution of disease in these populations will permit more precise targeting of control measures. PMID:15184440

The Deaf-Blind/Severely-Profoundly Handicapped: Proceedings from the 1978 Nebraska Statewide Conference, Nebraska Diagnostic Resource Center, Cozad, Nebraska.

ERIC Educational Resources Information Center

Clark, Douglas H., Ed.

The report presents the proceedings of a 1978 Nebraska statewide conference intitled "The Education and Training of the Deaf-Blind/Severely-Profoundly Handicapped." Titles and authors of the 13 papers presented include "Considerations for Full Educational Service for the Severely and Profoundly Handicapped" (N. Haring);…

Deficient Behavioral Inhibition and Anomalous Selective Attention in a Community Sample of Adolescents with Psychopathic Traits and Low-Anxiety Traits

ERIC Educational Resources Information Center

Vitale, Jennifer E.; Newman, Joseph P.; Bates, John E.; Goodnight, Jackson; Dodge, Kenneth A.; Pettit, Gregory S.

2005-01-01

Socialization is the important process by which individuals learn and then effectively apply the rules of appropriate societal behavior. Response modulation is a psychobiological process theorized to aid in socialization by allowing individuals to utilize contextual information to modify ongoing behavior appropriately. Using Hare's (1991)…

76 FR 18622 - Notice of Submission Deadline for Schedule Information for O'Hare International Airport, John F...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-04

... (JFK), and Newark Liberty International Airport (EWR) in accordance with the International Air..., Schedules Facilitated Airport, and JFK and EWR as Level 3, Coordinated Airports. Scheduled operations at JFK...) and at EWR and JFK from 6 a.m. to 11 p.m. Eastern Time (1100-0400 UTC). Carriers should submit...

75 FR 58020 - Notice of Submission Deadline for Schedule Information for O'Hare International Airport, John F...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-23

... (JFK), and Newark Liberty International Airport (EWR) in accordance with the International Air... INFORMATION: The FAA has designated ORD as an IATA Level 2, Schedules Facilitated Airport, and JFK and EWR as Level 3, Coordinated Airports. Scheduled operations at JFK and EWR are currently limited by the FAA by...

Psychopathic Predators? Getting Specific about the Relation between Psychopathy and Violence

ERIC Educational Resources Information Center

Camp, Jacqueline P.; Skeem, Jennifer L.; Barchard, Kimberly; Lilienfeld, Scott O.; Poythress, Norman G.

2013-01-01

Objective: The Psychopathy Checklist-Revised (PCL-R; Hare, 1991, 2003) is often used to assess risk of violence, perhaps based on the assumption that it captures emotionally detached individuals who are driven to prey upon others. This study is designed to assess the relation between (a) core interpersonal and affective traits of psychopathy and…

Mentoring Programs: The Great Hope or Great Hype? Critical Essay. ASHE/Lumina Fellows Series. Issue 7

ERIC Educational Resources Information Center

Smith, Buffy

2009-01-01

Mentoring has oftentimes been touted as critical to the academic success of underrepresented students defined as first-generation college students and/or students of color. Several studies on traditional mentor programs have reported success increasing the retention and graduation rates among underrepresented students (Haring, 1997; Jacobi, 1991;…

Ecology and conservation of lynx in the United States

Treesearch

Leonard F. Ruggiero; Keith B. Aubry; Steven W. Buskirk; Gary M. Koehler; Charles J. Krebs; Kevin S. McKelvey; John R. Squires

1999-01-01

Once found throughout the Rocky Mountains and forests of the northern states, the lynx now hides in pockets of its former range while feeding mostly on small animals like snowshoe hares. A team of government and university scientists review the newest scientific knowledge of this unique cat's history, distribution, and ecology. The chapters on this web site...

The Hare and the Tortoise: A Comparative Review of the Drive towards Inclusive Education Policies in England and Cyprus

ERIC Educational Resources Information Center

Jones, Caroline; Symeonidou, Simoni

2017-01-01

This paper explores the process of policy formulation and implementation in relation to children commonly described as having "special educational needs" and disability (SEND), in Cyprus and in England. Drawing on qualitative research evidence from key primary documentary sources including legislation, statutory and non-statutory…

The Normativity of the Helping Child--Meta-Ethnographic Perspectives on Individualised Learning in Age-Mixed Classrooms

ERIC Educational Resources Information Center

Huf, Christina; Raggl, Andrea

2017-01-01

This paper discusses possibilities of synthesising ethnographic data. This discussion implies a critical appraisal of the methodology of "Meta-Ethnography." Taking Noblit's and Hare's concept of Meta-Ethnography as a starting point to develop their own practice of synthesising data, the paper suggests to reconsider the possibility to…

Travel, Boundaries, and the Movement of Culture(s): Explanations for the Folk/Fine Art Quandary.

ERIC Educational Resources Information Center

White, John Howell; Congdon, Kristin G.

1998-01-01

Illustrates the difficulty in trying to establish clearly defined categories between art forms. Addresses the problem through discussions of three artists: Malcah Zeldis, Mabel Burkholder, and Keith Haring. Suggests that a travel metaphor grants people a flexible and historically-oriented way to speak about artwork and art categories. (CMK)

The Hare and the Water: A Tanzanian Folktale. Water in Africa.

ERIC Educational Resources Information Center

Abernathy-Tabor, Michelle

The Water in Africa Project was realized over a 2-year period by a team of Peace Corps volunteers, World Wise Schools (WWS) classroom teachers, and WWS staff members. As part of an expanded, detailed design, resources were collected from over 90 volunteers serving in African countries, photos and stories were prepared, and standards-based learning…

Factor Structure of the Hare Psychopathy Checklist: Youth Version (PCL: YV) in Adolescent Females

ERIC Educational Resources Information Center

Kosson, David S.; Neumann, Craig S.; Forth, Adelle E.; Salekin, Randall T.; Hare, Robert D.; Krischer, Maya K.; Sevecke, Kathrin

2013-01-01

Despite substantial evidence for the fit of the 3- and 4-factor models of Psychopathy Checklist-based ratings of psychopathy in adult males and adolescents, evidence is less consistent in adolescent females. However, prior studies used samples much smaller than recommended for examining model fit. To address this issue, we conducted a confirmatory…

The SRP-II as a Rich Source of Data on the Psychopathic Personality

ERIC Educational Resources Information Center

Lester, Whitney S.; Salekin, Randall T.; Sellbom, Martin

2013-01-01

This study examined the factor structure, external correlates, and predictive utility of the Self-Report Psychopathy scale (SRP-II; Hare, Harpur, & Hemphill, 1989). Despite a revision of the SRP-II to address, among other criticisms, a lack of items reflecting antisocial behavior, we hypothesized that the SRP-II would have a conceptually coherent…

Using the PCL-R to Help Estimate the Validity of Two Self-Report Measures of Psychopathy with Offenders

ERIC Educational Resources Information Center

Poythress, Norman G.; Lilienfeld, Scott O.; Skeem, Jennifer L.; Douglas, Kevin S.; Edens, John F.; Epstein, Monica; Patrick, Christopher J.

2010-01-01

Two self-report measures of psychopathy, Levenson's Primary and Secondary Psychopathy scales (LPSP) and the Psychopathic Personality Inventory (PPI), were administered to a large sample of 1,603 offenders. The most widely researched measure of criminal psychopathy, the Hare Psychopathy Checklist-Revised (PCL-R), served as a provisional referent…

Marked by Fire: Anishinaabe Articulations of Nationhood in Treaty Making with the United States and Canada

ERIC Educational Resources Information Center

Stark, Heidi Kiiwetinepinesiik

2012-01-01

The story, known as "The Theft of Fire," illustrates numerous meanings and teachings crucial to understanding Anishinaabe nationhood. This story contains two discernible points. First, it reveals how the Anishinaabe obtained fire. The second discernible feature within this story is the marking of the hare by his theft of fire. Stories…

77 FR 19076 - High Density Traffic Airports; Notice of Determination Regarding Low Demand Periods at Ronald...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-30

... 10 p.m. to 10:59 p.m. no longer is a low demand period at Ronald Reagan Washington National Airport... Airport, LaGuardia Airport, O'Hare International Airport, Ronald Reagan Washington National Airport (DCA...-1024] High Density Traffic Airports; Notice of Determination Regarding Low Demand Periods at Ronald...

76 FR 58393 - High Density Traffic Airports; Notice of Determination Regarding Low Demand Periods at Ronald...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-21

... 6 a.m. to 6:59 a.m. no longer is a low demand period at Ronald Reagan Washington National Airport... Airport, LaGuardia Airport, O'Hare International Airport, Ronald Reagan Washington National Airport (DCA...-1024] High Density Traffic Airports; Notice of Determination Regarding Low Demand Periods at Ronald...

14 CFR 93.28 - One-for-one trade of Arrival Authorizations.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false One-for-one trade of Arrival Authorizations. 93.28 Section 93.28 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES SPECIAL AIR TRAFFIC RULES Congestion and Delay Reduction at Chicago O'Hare International...

The Healthy Hare Family Coloring and Activity Book: Grades Kindergarten-3.

ERIC Educational Resources Information Center

Ohio State Dept. of Health, Columbus.

This activity and coloring booklet has been designed to supplement health lessons for primary grades students. Some of the activities are quite simple and require very little instruction and direction, while others are more difficult and require careful explanation prior to completion. The level of difficulty of the activities is varied in order…

Effects of climate change on wildlife in the Northern Rockies [Chapter 8

Treesearch

Kevin S. McKelvey; Polly C. Buotte

2018-01-01

Few data exist on the direct effects of climatic variability and change on animal species. Therefore, projected climate change effects must be inferred from what is known about habitat characteristics and the autecology of each species. Habitat for mammals, including predators (Canada lynx, fisher, wolverine) and prey (snowshoe hare) that depend on high-elevation,...

Psychopathy and Suicidality in Female Offenders: Mediating Influences of Personality and Abuse

ERIC Educational Resources Information Center

Verona, Edelyn; Hicks, Brian M.; Patrick, Christopher J.

2005-01-01

The influence of personality and childhood abuse on suicidal behaviors and psychopathy was examined among female prisoners. Scores on the affective/interpersonal component (Factor 1; F1) and the antisocial deviance (Factor 2; F2) component of psychopathy were obtained from the Psychopathy Checklist-Revised (R. D. Hare, 1991). Suicide attempt and…

The Self-Awareness of Young Adepts of the Hare Krishna Cult

ERIC Educational Resources Information Center

Kurachev, D. G.

2012-01-01

The religious movement known as the International Society for Krishna Consciousness (ISKCON) was founded by the Indian religious teacher Abhay Charan De Bhaktivedanta (1896-1977), who went by the ritual name Bhaktivinanda Swami Shrila Prabhupada. The movement first showed up in Russia in 1971. At the present time the Association of ISKCON Communes…

Gender Differences in Structured Risk Assessment: Comparing the Accuracy of Five Instruments

ERIC Educational Resources Information Center

Coid, Jeremy; Yang, Min; Ullrich, Simone; Zhang, Tianqiang; Sizmur, Steve; Roberts, Colin; Farrington, David P.; Rogers, Robert D.

2009-01-01

Structured risk assessment should guide clinical risk management, but it is uncertain which instrument has the highest predictive accuracy among men and women. In the present study, the authors compared the Psychopathy Checklist-Revised (PCL-R; R. D. Hare, 1991, 2003); the Historical, Clinical, Risk Management-20 (HCR-20; C. D. Webster, K. S.…

Why We Got Serious about Interdisciplinary Teaching

ERIC Educational Resources Information Center

Haring, Dana; Kelner, Tom

2016-01-01

When Tom Kelner, a 7th grade social studies teacher, realized that under the Common Core standards he'd be responsible for strengthening students' reading, writing, and research skills in his social studies classes, first he panicked. Then he approached Dana Haring, an English language arts teacher on his 7th grade team, and asked if they could…

78 FR 57677 - Notice of Submission Deadline for Schedule Information for O'Hare International Airport, San...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-19

... significant at the typical demand levels, especially when available runways or adverse weather conditions... retime flights to less congested periods. Slots for new flights will be limited to off-peak times to... extent possible. Currently, the peak demand period at SFO is approximately 0900 to 1400 Pacific Time. In...

Cohesion Research: Conceptual and Methodological Issues

DTIC Science & Technology

1990-09-01

Hare, 1976; Ivancevich, Szilagyi , & Wallace , 1977; Lott & Lott, 1965), no quantitative research integration of the literature had been accomplished...maintaining group identity (p. 424). Ivancevich, Szilagyi , and Wallace (1977) defined cohesiveness as an 2 "atmosphere of closeness, or common attitudes...Ivancevich, i. M., Szilagyi , A. D. Jr., & Wallace , M. J. Jr. (1977). Organizational behavior and gerformance. Jackson, G. B. (1980). Methods for integrative

Disentangling the Underlying Dimensions of Psychopathy and Conduct Problems in Childhood: A Community Study

ERIC Educational Resources Information Center

Dadds, Mark R.; Fraser, Jenny; Frost, Aaron; Hawes, David J.

2005-01-01

The psychometric and predictive validity of callous-unemotional (CU) traits as an early precursor of conduct disorder and antisocial behavior were assessed. A community sample of children (4-9 years of age) were tested 12 months apart with the Antisocial Process Screening Device (APSD; P. J. Frick & R. D. Hare, 2002), a measure of early signs of…

Experimental investigation of the role of thyrocalcitonin in the prophylaxis of disturbances in the water-salt and mineral metabolism during a 30-day hypokinesia

NASA Technical Reports Server (NTRS)

Shashkov, V. S.; Yegorov, B. B.; Dmitriyev, B. S.; Volozhin, A. N.; Krotov, B. P.

1979-01-01

The effect of thyrocalcitonin (TCT) injections on the metabolism of water and electrolytes in free-moving and immobilized chinchilla hares is described. Calcium excretion from immobilized animals was elevated, but normalized in those also receiving TCT injections. TCT also normalized water content and excretion rates.

Confirmatory Factor Analysis of the Psychopathy Checklist: Screening Version in Offenders With Axis I Disorders

ERIC Educational Resources Information Center

Hill, Christie D.; Neumann, Craig S.; Rogers, Richard

2004-01-01

One hundred forty-nine inpatients within a maximum security psychiatric facility were assessed with the Psychopathy Checklist: Screening Version (PCL:SV; S. D. Hart, D. N. Cox, & R. D. Hare, 1995). Within the total sample, 68% had a psychotic disorder and 30% met criteria for psychopathy. Using confirmatory factor analysis, the authors tested the…

78 FR 19356 - Notice of Schedule Information Submission Deadline for O'Hare International Airport, San...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-29

... Airport (SFO), New York's John F. Kennedy International Airport (JFK), and Newark Liberty International... Level 2 airport, SFO as a Level 2 airport, JFK as a Level 3 airport, and EWR as a Level 3 airport. Scheduled operations at JFK and EWR are currently limited by FAA Orders until a final Congestion Management...

77 FR 19410 - Notice of Schedule Information Submission Deadline for O'Hare International Airport, San...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-30

... Airport (SFO), New York's John F. Kennedy International Airport (JFK), and Newark Liberty International... Level 2 airport, SFO as a Level 2 airport, JFK as a Level 3 airport, and EWR as a Level 3 airport. Scheduled operations at JFK and EWR are currently limited by FAA Orders until a final Congestion Management...

Relations between Temperament and Theory of Mind Development in the United States and China: Biological and Behavioral Correlates of Preschoolers' False-Belief Understanding

ERIC Educational Resources Information Center

Lane, Jonathan D.; Wellman, Henry M.; Olson, Sheryl L.; Miller, Alison L.; Wang, Li; Tardif, Twila

2013-01-01

The emotional reactivity hypothesis holds that, over the course of phylogeny, the selection of animals with less reactive temperaments supported the development of sophisticated social-cognitive skills in several species, including humans (Hare, 2007). In the ontogenetic human case, an emotional reactivity hypothesis predicts that children with…

An OER Framework, Heuristic and Lens: Tools for Understanding Lecturers' Adoption of OER

ERIC Educational Resources Information Center

Cox, Glenda; Trotter, Henry

2017-01-01

This paper examines three new tools--a framework, an heuristic and a lens--for analysing lecturers' adoption of OER in higher educational settings. Emerging from research conducted at the universities of Cape Town (UCT), Fort Hare (UFH) and South Africa (UNISA) on why lecturers adopt--or do not adopt--OER, these tools enable greater analytical…

75 FR 69158 - Quarterly Publication of Individuals, Who Have Chosen To Expatriate, as Required by Section 6039G

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-10

... Claudia Burger Elizabeth Joyce Callaghan John Arthur Campeau Pamela Gail Cannon Ralph George Carlson Helma... Given Gail Kathleen Gorr Marc-Andrew George Grace John S. Graf Robert Henri Grau Joachim Gray Laurence... Ellen Mary Hampton Peter Henry Han Choi Sang Han Richard Jin Soo Hare David Edwin George Harmon Sangboon...

77 FR 75646 - Kenai National Wildlife Refuge, Soldotna, AK; Draft Environmental Impact Statement for the...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-21

..., and Cook Inlet Region, Inc. (CIRI), owns the subsurface estate of coal, oil, and gas in the project..., snowshoe hares, and numerous species of Neotropical birds, such as olive-sided flycatchers, myrtle warblers... received the subsurface oil, gas, and coal estate to nearly 200,000 acres within the Refuge as part of its...

78 FR 32270 - Kenai National Wildlife Refuge, Soldotna, AK; Environmental Impact Statement for the Shadura...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-29

.... (CIRI), owns the subsurface estate of coal, oil, and gas in the project area. The project would be in... and brown bears, lynx, snowshoe hares, and numerous species of Neotropical birds, such as olive-sided... within the Refuge, portions of the subsurface estate, consisting of the oil, gas, and coal are owned by...

A Meta-Ethnography of Two Studies on Interactions in Schools: Reflections on the Process of Translation

ERIC Educational Resources Information Center

Kakos, Michalis; Fritzsche, Bettina

2017-01-01

This paper reflects upon our experience gained from engagement in a meta-ethnography of two studies on interactions between teachers and students in schools situated in England and Germany. Starting with a short overview of Noblit and Hare's (1988) conceptualisation of the method, the paper outlines the meta-ethnography we undertook especially…

Balsam Fir Dominant Species Under Rethinned Northern White-Cedar

Treesearch

William F. Johnston

1972-01-01

A 20-year thinning study in a Wisconsin swamp stand of middle-aged northern white-cedar indicates that advance tree reproduction and shrubs grow little under after a second thinning to less than 150 square feet of basal area per acre. Balsam fir will probably dominate this undergrowth, particularly if the area is used heavily by snowshoe hare or white-tailed deer....

Afghan Tortoise, Korean Hare: Advising in Hard and Soft Cultures

DTIC Science & Technology

2010-01-01

turned generally positive with the success of Christian missionaries. In contrast, Afghanistan’s experience was as a pawn in the hegemonic struggle...Hofstede analyzed values through four quantifiable dimensions: power distance, collectivism versus individualism, masculinity versus femininity, and...the relationship between people and the group. Masculinity versus femininity measured the values associated with the roles of men and women

A Multimethod Assessment of Juvenile Psychopathy: Comparing the Predictive Utility of the PCL:YV, YPI, and NEO PRI

ERIC Educational Resources Information Center

Cauffman, Elizabeth; Kimonis, Eva R.; Dmitrieva, Julia; Monahan, Kathryn C.

2009-01-01

The current study compares 3 distinct approaches for measuring juvenile psychopathy and their utility for predicting short- and long-term recidivism among a sample of 1,170 serious male juvenile offenders. The assessment approaches compared a clinical interview method (the Psychopathy Checklist: Youth Version [PCL:YV]; Forth, Kosson, & Hare,…

Factor Structure of the Hare Psychopathy Checklist: Youth Version in German Female and Male Detainees and Community Adolescents

ERIC Educational Resources Information Center

Sevecke, Kathrin; Pukrop, Ralf; Kosson, David S.; Krischer, Maya K.

2009-01-01

Substantial evidence exists for 3- and 4-factor models of psychopathy underlying patterns of covariation among the items of the Psychopathy Checklist-Revised (PCL-R) in diverse adult samples. Although initial studies conducted with the Psychopathy Checklist: Youth Version (PCL:YV) indicated reasonable fit for these models in incarcerated male…

A Taxometric Analysis of the Psychopathy Checklist: Screening Version (PCL:SV): Further Evidence of Dimensionality

ERIC Educational Resources Information Center

Walters, Glenn D.; Gray, Nicola S.; Jackson, Rebecca L.; Sewell, Kenneth W.; Rogers, Richard; Taylor, John; Snowden, Robert J.

2007-01-01

A taxometric analysis of the Psychopathy Checklist: Screening Version (PCL:SV; S. D. Hart, D. N. Cox, & R. D. Hare, 1995) was performed on a group of 2,250 male and female forensic/psychiatric patients and jail/prison inmates. The 4 PCL:SV facet scores (Interpersonal, Affective, Impulsive Lifestyle, Antisocial Behavior) served as indicators in…

Is Criminal Behavior a Central Component of Psychopathy? Conceptual Directions for Resolving the Debate

ERIC Educational Resources Information Center

Skeem, Jennifer L.; Cooke, David J.

2010-01-01

The development of the Psychopathy Checklist-Revised (PCL-R; R. D. Hare, 2003) has fueled intense clinical interest in the construct of psychopathy. Unfortunately, a side effect of this interest has been conceptual confusion and, in particular, the conflating of measures with constructs. Indeed, the field is in danger of equating the PCL-R with…

Acceleration of vegetation turnover and element cycling by mammalian herbivory in riparian ecosystems

Treesearch

Lem G. Butler; Knut Kielland

2008-01-01

1. We examined the effects of browsing by moose and snowshoe hares on vegetation structure, species composition, plant demography and element cycling in 25 riparian (willow) vegetation stands along the Tanana River, interior Alaska, across a 250-km gradient that represented a fivefold range in moose densities (0.2 to 1.0 km-2). 2. Browsing...

The Problem of Dirty Hands: The Moral Dilemma of Public Life.

DTIC Science & Technology

1981-04-21

ridden? Once this question is asked, a " slippery slope " seems to take effect in which the absoluteness of a *1 R.M. Hare, "Rules of " and Moral...but what of less clear dis- tinctions? Euthanasia , for instance, most often becomes an issue in cases where the choices seem to be between allowing a

Personal Care and the Healthy Hare Family Coloring and Activity Book for Grades 2-3.

ERIC Educational Resources Information Center

Ohio State Dept. of Health, Columbus.

This activity and coloring booklet has been designed to supplement health lessons for students in grades 2-3. Some of the activities are quite simple and require very little instruction and direction, while others are more difficult and require careful explanation prior to completion. The level of difficulty of the activities is varied in order to…

"I Always Wanted to Be a Hero." Life without Parole

ERIC Educational Resources Information Center

Roth, Angela M.

2013-01-01

In this article, the author recalls her face-to-face meeting with a prison inmate. Paul Jensen is currently serving a life sentence without parole in South Dakota for a crime committed at age 14. In January 1996, Paul was involved in a robbery that went tragically wrong and resulted in the shooting death of taxi cab driver Michael Hare. Three…

Isolation of Mycobacterium avium subspecies paratuberculosis from non-ruminant wildlife living in the sheds and on the pastures of Greek sheep and goats.

PubMed

Florou, M; Leontides, L; Kostoulas, P; Billinis, C; Sofia, M; Kyriazakis, I; Lykotrafitis, F

2008-05-01

This study aimed to: (1) investigate whether non-ruminant wildlife interfacing with dairy sheep and goats of four Greek flocks endemically infected with Mycobacterium avium subspecies paratuberculosis (MAP) harboured MAP and (2) genetically compare the strains isolated from the wildlife to those isolated from the small ruminants of these flocks. We cultured and screened, by polymerase chain reaction (PCR), pooled-tissue samples from 327 wild animals of 11 species for the MAP-specific IS900 insertion sequence. We also cultured faecal samples from 100 sheep or goats from each of the four flocks. MAP was detected in samples from 11 sheep, 12 goats, two mice, two rats, a hare and a fox. Only one rat had histopathological findings. Genetic typing categorized 21 isolates as cattle-type strains and two, from a house mouse and a goat respectively, as sheep-type strains; this is the first report of a rodent harbouring a sheep-type strain. The MAP types that were most frequently isolated amongst the sheep and goats of each flock were also the ones isolated from sympatric rodents; those isolated from the fox and hare also belonged to the predominant ruminant strains.

Climate change surpasses land-use change in the contracting range boundary of a winter-adapted mammal

PubMed Central

Sultaire, Sean M.; Pauli, Jonathan N.; Martin, Karl J.; Meyer, Michael W.; Notaro, Michael; Zuckerberg, Benjamin

2016-01-01

The effects of climate change on biodiversity have emerged as a dominant theme in conservation biology, possibly eclipsing concern over habitat loss in recent years. The extent to which this shifting focus has tracked the most eminent threats to biodiversity is not well documented. We investigated the mechanisms driving shifts in the southern range boundary of a forest and snow cover specialist, the snowshoe hare, to explore how its range boundary has responded to shifting rates of climate and land cover change over time. We found that although both forest and snow cover contributed to the historical range boundary, the current duration of snow cover best explains the most recent northward shift, while forest cover has declined in relative importance. In this respect, the southern range boundary of snowshoe hares has mirrored the focus of conservation research; first habitat loss and fragmentation was the stronger environmental constraint, but climate change has now become the main threat. Projections of future range shifts show that climate change, and associated snow cover loss, will continue to be the major driver of this species' range loss into the future. PMID:27030410

Installation Restoration Program Phase 1 - Records Search, O’Hare Air Reserve Forces Facility, Illinois

DTIC Science & Technology

1983-12-01

clarifiers, activated sludge units, trickling filters, aerobic and anaerobic digesters, and various dowatering devices and recommendations for...for locations of water- bearing fractures. Additional responsibilities included drilling with mud and air rotary drilling rigs as well as bucket auger...interpretation. Also conducted earth resistivity surveys in Georgia and Alabama Piedmont Provinces for locations of water- bearing fractures. Additional

77 FR 58608 - Notice of Submission Deadline for Schedule Information for O'Hare International Airport, San...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-21

... (SFO), New York's John F. Kennedy International Airport (JFK), and Newark Liberty International Airport... designated ORD as an IATA Level 2 airport, SFO as a Level 2 airport, JFK as a Level 3 airport, and EWR as a Level 3 airport. Scheduled operations at JFK and EWR are currently limited by FAA Orders until a final...

Commercial contracts and the moral contract: a response to Nigel Cameron.

PubMed

Hare, J E

1994-03-01

John E. Hare responds to Cameron's article by challenging the adequacy of the Hippocratic Oath as a basis for ethical medicine. The Oath promoted a "guild mentality" that is evident, for example, in modern medicine's resistance to alternative forms of practice. Christians need to "winnow" bioethical views, both those traditionally honored and those that confront us because of new medical developments.

Software Description for the O’Hare Runway Configuration Management System. Volume II. Low-Level Pseudocode,

DTIC Science & Technology

1982-10-01

BACK_ GVRATON; (geserate log me"ses from wather and wind planning log screenJ PERFORN AIPORT.PLANNIG LOGISSA ORItATION; (eSamrate log message from...ISSAGN H31.TAL(COUNT) .26 -kAUX imesase is constructed with wather imforimetiom ad stated) IF(VILO.TAM(J).DIl A(S)’ ’)1 (VXLOG.TABL(J).VU.(S)’ THEN

Hares, Tortoises and the Social Construction of the Pupil: Differentiated Learning in French and English Primary Schools

ERIC Educational Resources Information Center

Raveaud, Maroussia

2005-01-01

This article examines differentiation by task as it is used and perceived in French and English primary schools. It highlights the influence of national context on teaching and learning. The study rests on classroom observations in 12 Key Stage 1 classes located in socially disadvantaged areas. The first section sets the mission of schooling in a…

Psychopathy and the Combination of Psychopathy and Sexual Deviance as Predictors of Sexual Recidivism: Meta-Analytic Findings Using the Psychopathy Checklist-Revised

ERIC Educational Resources Information Center

Hawes, Samuel W.; Boccaccini, Marcus T.; Murrie, Daniel C.

2013-01-01

Clinicians routinely administer Hare's (2003) Psychopathy Checklist-Revised (PCL-R) to sex offenders and report PCL-R scores as meaningful predictors of recidivism risk. Although a 2005 meta-analysis reported a small (d = 0.29) association between PCL-R scores and sexual recidivism (Hanson & Morton-Bourgon, 2005), no meta-analysis has examined…

Cauldrons: An Abstraction for Concurrent Problems Solving. Revision.

DTIC Science & Technology

1986-09-01

iaCtio1ns are the cauldron, a mechanism for organizing inference into distinct reasoning contexts: the flmse. a way of mnodularly describing the components...reasoning systems. 1 . Main Points This paper develops three mechanisms for organizing large distributed reasoning systems: Cauldrons -- A chunk of...introduction.s ’Thc goal-node/frame mechanism supports a useful abstraction over the hare cauldrons implementation, providing a protocol for organizing

The Protean Shape of the Writing Associate's Role: An Empirical Study and Conceptual Model

ERIC Educational Resources Information Center

Cairns, Rhoda; Anderson, Paul V.

2008-01-01

Writing fellow or writing associate (WA) programs trace their heritage to a single point of origin: the model developed at Brown University in the early 1980s by Tori Haring-Smith (Soven, 1993, 2001). Since then, the Brown model has spread to hundreds of schools. WA programs are so adaptable because they consist of many discrete elements, each of…

Predators as prey at a Golden Eagle Aquila chrysaetos eyrie in Mongolia

USGS Publications Warehouse

Ellis, D.H.; Tsengeg, Pu; Whitlock, P.; Ellis, Merlin H.

2000-01-01

Although golden eagles (Aquila chrysaetos) have for decades been known to occasionally take large or dangerous quarry, the capturing of such was generally believed to be rare and/or the act of starved birds. This report provides details of an exceptional diet at a golden eagle eyrie in eastern Mongolia with unquantified notes on the occurrence of foxes at other eyries in Mongolia. Most of the prey we recorded were unusual, including 1 raven (Corvus corax), 3 demoiselle cranes (Anthropoides virgo), 1 upland buzzard (Buteo hemilasius), 3 owls, 27 foxes, and 11 Mongolian gazelles. Some numerical comparisons are of interest. Our value for gazelle calves (10 minimum count, 1997) represents 13% of 78 prey items and at least one adult was also present. Our total of only 15 hares (Lepus tolai) and 4 marmots (Marmota sibirica) compared to 27 foxes suggests not so much a preference for foxes, but rather that populations of more normal prey were probably depressed at this site. Unusual prey represented 65% of the diet at this eyrie.

Stochastic events lead to accretion in Saturn’s rings

NASA Astrophysics Data System (ADS)

Esposito, L. W.

2009-12-01

UVIS occultations indicate accretion is triggered at the B ring edge, in strong density waves in ring A and in the F ring. Moons may trigger accretion by streamline crowding (Lewis & Stewart); which enhances collisions, leading to accretion; increasing random velocities; leading to more collisions and more accretion. Cassini occultations of these strongly perturbed locations show not only accretion but also disaggregation, with time scales of hours to weeks. The collisions may lead to temporary aggregations via stochastic events: they can compress unconsolidated objects, trigger adhesion or bring small pieces into contact with larger or higher-density seeds. Disaggregation then can follow from disruptive collisions or tidal shedding. In the accretion/disruption balance, increased random motions could eventually give the upper hand to disruption… just as ‘irrational exuberance’ can lead to financial panic in the economy; or the overpopulation of hares can lead to boom-and-bust in the population of foxes. This unstable equilibrium can similarly give rise to episodic cycles in accretion: explaining why the observable ring features that indicate embedded objects have been increasing since the beginning of Cassini’s observations of Saturn in 2004.

Stochastic events lead to accretion in Saturn's rings

NASA Astrophysics Data System (ADS)

Esposito, Larry W.

2010-05-01

UVIS occultations indicate accretion is triggered at the B ring edge, in strong density waves in ring A and in the F ring. Moons may trigger accretion by streamline crowding (Lewis & Stewart); which enhances collisions, leading to accretion; increasing random velocities; leading to more collisions and more accretion. Cassini occultations of these strongly perturbed locations show not only accretion but also disaggregation, with time scales of hours to weeks. The collisions may lead to temporary aggregations via stochastic events: collisions can compress unconsolidated objects, trigger adhesion or bring small pieces into contact with larger or higher-density seeds. Disaggregation then can follow from disruptive collisions or tidal shedding. In the accretion/disruption balance, increased random motions could eventually give the upper hand to disruption… just as ‘irrational exuberance' can lead to financial panic in the economy; or the overpopulation of hares can lead to boom-and-bust in the population of foxes. This unstable equilibrium can similarly give rise to episodic cycles in accretion: explaining why the observable ring features that indicate embedded objects have been increasing since the beginning of Cassini's observations of Saturn in 2004.

Emotional Intelligence and Callous-Unemotional Traits in Incarcerated Adolescents.

PubMed

Kahn, Rachel E; Ermer, Elsa; Salovey, Peter; Kiehl, Kent A

2016-12-01

Emotional intelligence (EI) is the ability to perceive, manage, and reason about emotions and to use this information to guide thinking and behavior adaptively. Youth with callous-unemotional (CU) traits demonstrate a variety of affective deficits, including impairment in recognition of emotion and reduced emotional responsiveness to distress or pain in others. We examined the association between ability EI and CU traits in a sample of incarcerated adolescents (n = 141) using an expert-rater device (Psychopathy Checklist Youth Version (PCL-YV; Manual for the Hare psychopathy checklist: Youth version. Multi-Health Systems, Toronto, 2003) and self-report assessments of CU traits. EI was assessed using the Mayer-Salovey-Caruso Emotional Intelligence Test-Youth Version, Research Version (MSCEIT-YV-R; MSCEIT YV: Mayer-Salovey-Caruso emotional intelligence test: Youth version, research version 1.0. Multi-Health Systems, Toronto, Ontario, 2005). Similar to findings in adult forensic populations, high levels of CU traits in incarcerated adolescents were associated with lower EI, particularly higher order EI skills. Identifying impairment on EI abilities may have important implications for emerging treatment and intervention developments for youth with high levels of CU traits.

ATYPICAL CHLAMYDIACEAE IN WILD POPULATIONS OF HAWKS ( BUTEO SPP.) IN CALIFORNIA.

PubMed

Luján-Vega, Charlene; Hawkins, Michelle G; Johnson, Christine K; Briggs, Christopher; Vennum, Chris; Bloom, Peter H; Hull, Joshua M; Cray, Carolyn; Pesti, Denise; Johnson, Lisa; Ciembor, Paula; Ritchie, Branson R

2018-03-01

Chlamydiaceae bacteria infect many vertebrate hosts, and previous reports based on polymerase chain reaction (PCR) assays and serologic assays that are prone to cross-reaction among chlamydial organisms have been used to describe the prevalence of either DNA fragments or antibodies to Chlamydia spp. in wild raptorial populations. This study reports the PCR-based prevalence of Chlamydiaceae DNA that does not 100% match any avian or mammalian Chlamydiaceae in wild populations of hawks in California Buteo species. In this study, multimucosal swab samples ( n = 291) for quantitative PCR (qPCR) and plasma ( n = 78) for serology were collected from wild hawks. All available plasma samples were negative for antibodies using a C. psittaci-specific elementary body agglutination test (EBA; n = 78). For IgY antibodies all 51 available samples were negative using the indirect immunofluorescent assay. The overall prevalence of Chlamydiaceae DNA detection in wild Buteo species sampled was 1.37% (4/291) via qPCR-based analysis. Two fledgling Swainson's hawks ( Buteo swainsoni) and two juvenile red-tailed hawks ( Buteo jamaicensis) were positive by qPCR-based assay for an atypical chlamydial sequence that did not 100% match any known C. psittaci genotype. Positive swab samples from these four birds were sequenced based on the ompA gene and compared by high-resolution melt analysis with all known avian and mammalian Chlamydiaceae. The amplicon sequence did not 100% match any known avian chlamydial sequence; however, it was most similar (98.6%) to C. psittaci M56, a genotype that is typically found in muskrats and hares. Culture and full genome sequence analysis of Chlamydia spp. isolated from diseased hawks will be necessary to classify this organism and to better understand its epizootiology and potential health impact on wild Buteo populations in California.

A Normative Model of Work Team Effectiveness

DTIC Science & Technology

1983-11-01

Hawthc-ne studies at Western Electric Corporation, Harold Leavitt (1975) observed: Far and away the most powerful and beloved tool of applied behavioral ...scientists is the small face-to-face group. Since the Western Electric researches, behavioral scientists have been learning to understand, exploit and...integration of literature on small group behavior , see McGrath and Altman (1966). Current reviews are provided by Hare (1976), MicGrath and Kravitz (1982

Annual Research Progress Report for Fiscal Year 1983,

DTIC Science & Technology

1983-10-01

Crossover Study. (0) C-60-83 tifedipine in Patients with Recurrent Episodes of Bronchospasm. 124 (0) C-66-83 Epidemiological , Clinical and Therapeutic...study in the utilization of a phased response disaster plan. Third World Congress in Emergency and Disaster Medicine, 25 May 83, Rome, Italy...nonallergic rhinitis with eosinophilia (HARES)? and b. Are patients with MARES - or any identifiable subset thereof - at particular risk of developing lower

Reliability and Construct Validity of the Dutch Psychopathy Checklist: Youth Version--Findings from a Sample of Male Adolescents in a Juvenile Justice Treatment Institution

ERIC Educational Resources Information Center

Das, Jacqueline; de Ruiter, Corine; Doreleijers, Theo; Hillege, Sanne

2009-01-01

The present study examines the reliability and construct validity of the Dutch version of the Psychopathy Check List: Youth Version (PCL:YV) in a sample of male adolescents admitted to a secure juvenile justice treatment institution (N = 98). Hare's four-factor model is used to examine reliability and validity of the separate dimensions of…

77 FR 26667 - Standard Instrument Approach Procedures, and Takeoff Minimums and Obstacle Departure Procedures...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-07

.... 97.20 of Title 14 of the Code of Federal Regulations. The large number of SIAPs, their complex nature...-12 MN Mankato Mankato Rgnl........ 2/1869 4/20/12 RNAV (GPS) RWY 22, Orig 31-May-12 TN Memphis... IL Chicago Chicago O'Hare Intl. 2/6031 4/11/12 ILS OR LOC RWY 4R, Amdt 6L 31-May-12 MN Cloquet...

Expansive Cements

DTIC Science & Technology

1970-10-01

plastic or semi- plastic concrete and place no stress on the restraint provided. If, on the other hand, the ettringite continues to form rapidly for too...yield, I and wp.ter-cement ratio. Such a change in cement content may cause a greater change in expansion caracteristics than the change in...the tendency toward plastic shrinkage is increased. During the w’nter znths most structural concrete installations hare had adequate heating and no

The Potential and Flux Landscape Theory of Ecology

PubMed Central

Zhang, Kun; Wang, Erkang; Wang, Jin

2014-01-01

The species in ecosystems are mutually interacting and self sustainable stable for a certain period. Stability and dynamics are crucial for understanding the structure and the function of ecosystems. We developed a potential and flux landscape theory of ecosystems to address these issues. We show that the driving force of the ecological dynamics can be decomposed to the gradient of the potential landscape and the curl probability flux measuring the degree of the breaking down of the detailed balance (due to in or out flow of the energy to the ecosystems). We found that the underlying intrinsic potential landscape is a global Lyapunov function monotonically going down in time and the topology of the landscape provides a quantitative measure for the global stability of the ecosystems. We also quantified the intrinsic energy, the entropy, the free energy and constructed the non-equilibrium thermodynamics for the ecosystems. We studied several typical and important ecological systems: the predation, competition, mutualism and a realistic lynx-snowshoe hare model. Single attractor, multiple attractors and limit cycle attractors emerge from these studies. We studied the stability and robustness of the ecosystems against the perturbations in parameters and the environmental fluctuations. We also found that the kinetic paths between the multiple attractors do not follow the gradient paths of the underlying landscape and are irreversible because of the non-zero flux. This theory provides a novel way for exploring the global stability, function and the robustness of ecosystems. PMID:24497975

Brain response to empathy-eliciting scenarios involving pain in incarcerated psychopaths

PubMed Central

Decety, Jean; Skelly, Laurie R.; Kiehl, Kent A.

2013-01-01

Context A marked lack of empathy is a hallmark characteristic of individuals with psychopathy. However, neural response associated to empathic processing has not yet been directly examined in psychopathy especially in response to the perception of other people in pain and distress. Objective To identify potential differences in patterns of neural activity in incarcerated psychopaths and incarcerated controls during the perception of empathy-eliciting stimuli depicting other people in pain. Design In a case-control study, brain activation patterns elicited by dynamic stimuli depicting individuals being harmed and facial expression of pain were compared between incarcerated psychopaths and incarcerated controls. Setting Participants were scanned in on the grounds of a correctional facility using the Mind Research Network's mobile 1.5 T MRI system. Participants Eighty incarcerated males were classified according to scores on the Hare Psychopathy Checklist-Revised (PCL-R) as high (n = 27; PCL-R =30), intermediate (n = 28; PCL-R between 21–29), or low (n = 25; PCL-R ≤20) on psychopathy. Main Outcome Measure Neuro-hemodynamic response to empathy-eliciting dynamic scenarios revealed by functional magnetic resonance imaging. Results Psychopaths exhibited significantly less activation in the ventromedial prefrontal cortex, lateral orbitofrontal cortex, and periaqueductal gray relative to controls, but showed greater activation in the insula. Conclusion In response to pain cues expressed by others, psychopaths exhibit deficits in vmPFC and OFC regardless of stimulus type, but display selective impairment in processing facial cues of distress in regions associated with cognitive mentalizing. PMID:23615636

Isolation of Mycobacterium avium subspecies paratuberculosis from non-ruminant wildlife living in the sheds and on the pastures of Greek sheep and goats

PubMed Central

FLOROU, M.; LEONTIDES, L.; KOSTOULAS, P.; BILLINIS, C.; SOFIA, M.; KYRIAZAKIS, I.; LYKOTRAFITIS, F.

2008-01-01

SUMMARY This study aimed to: (1) investigate whether non-ruminant wildlife interfacing with dairy sheep and goats of four Greek flocks endemically infected with Mycobacterium avium subspecies paratuberculosis (MAP) harboured MAP and (2) genetically compare the strains isolated from the wildlife to those isolated from the small ruminants of these flocks. We cultured and screened, by polymerase chain reaction (PCR), pooled-tissue samples from 327 wild animals of 11 species for the MAP-specific IS900 insertion sequence. We also cultured faecal samples from 100 sheep or goats from each of the four flocks. MAP was detected in samples from 11 sheep, 12 goats, two mice, two rats, a hare and a fox. Only one rat had histopathological findings. Genetic typing categorized 21 isolates as cattle-type strains and two, from a house mouse and a goat respectively, as sheep-type strains; this is the first report of a rodent harbouring a sheep-type strain. The MAP types that were most frequently isolated amongst the sheep and goats of each flock were also the ones isolated from sympatric rodents; those isolated from the fox and hare also belonged to the predominant ruminant strains. PMID:17578601

A case of typhoidal tularemia in a male Japanese farmer.

PubMed

Nakamura, Kiwamu; Fujita, Hiromi; Miura, Tomoya; Igata, Yu; Narita, Masashi; Monma, Naota; Hara, Yasuka; Saito, Kyoichi; Matsumoto, Akinori; Kanemitsu, Keiji

2018-06-01

In Japan, most tularemia cases occur after contact with hares (hunting, cooking) and involve the glandular or ulceroglandular form. Here, we present a case of typhoidal tularemia in a 72-year-old Japanese male farmer who presented with fever, fatigue, and right lower abdominal pain. Computed tomography revealed intestinal wall thickening at the ascending colon, pleural effusion, and ascites. Following an initial diagnosis of bacterial enteric infection, his symptoms deteriorated after a week-long cephalosporin treatment course. The patient lived in an area endemic for scrub typhus; the antibiotic was changed to a tetracycline on suspicion of scrub typhus infection. His symptoms rapidly improved after initiation of minocycline treatment. Later, blood tests revealed marked increases in serological tests against Francisella tularensis exclusively, and the patient was diagnosed with typhoidal tularemia. Typhoidal tularemia may be characterized by any combination of general symptoms, but does not exhibit the local manifestations associated with other forms of tularemia. The patient, in this case, had no direct contact with hares or other wild animals and did not present with local manifestations of tularemia. Physicians should consider this disease, especially when tick-borne disease is suspected in the absence of local wounds, eschar, ulcers, or lymphadenopathy. Copyright © 2018 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Serological surveillance of Leptospirosis in Italy: two‑year national data (2010‑2011).

PubMed

Tagliabue, Silvia; Figarolli, Bianca Maria; D'Incau, Mario; Foschi, Giovanni; Gennero, Maria Silvia; Giordani, Roberta; Giordani, Roberta; Natale, Alda; Papa, Paola; Ponti, Nicoletta; Scaltrito, Domenico; Spadari, Luisa; Vesco, Gesualdo; Ruocco, Luigi

2016-06-30

Nowadays, leptospirosis is a re‑emerging widespread infectious disease often underestimate worldwide. The National Reference Centre for Leptospirosis (NRCL), at the Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Brescia (Italy), with the cooperation of all the other Istituti Zooprofilattici Sperimentali (IIZZSS), evaluated the distribution of such important zoonosis in Italy. Serological data obtained between 2010‑2011 by each laboratory were collected by the NRCL and discussed. Serum samples collected from 43,935 animal specimens were analysed by the Microscopic Agglutination Test (MAT), using a panel of 8 serogroups as antigens (Australis, Ballum, Canicola, Grippotyphosa, Icterohaemorrhagiae, Pomona, Sejroe, Tarassovi). A MAT cut‑off of 1:100 was used to identify the serological positivities, 6,279 sera showed positive titers. Bovine (46.9%), swine (27.5%), ovine and goat (7.4%), dog (6.9%), and wild boar (4.5%) samples were delivered to the Laboratories more frequently than equine and other species sera. Data analysis showed that the most common serogroups in Italy are: Australis present in dogs, wild boars, horses, hares, swine, foxes, and rodents; Sejroe detected in cattle, sheep, goats, and buffaloes; Icterohaemorrhagiae present in dogs, goats, and foxes; Pomona detected in swine, cattle, and wild species; Grippotyphosa reported in hares.

Sarcoptic mange in Swedish wildlife.

PubMed

Mörner, T

1992-12-01

Mange caused by Sarcoptes scabiei var. vulpes appeared among red foxes (Vulpes vulpes) in Scandinavia (south-west Finland) for the first time in this century in 1967. The disease was most probably introduced by foxes crossing the Gulf of Finland from Estonia. The mange epizootic spread northwards through Finland and reached Sweden in late 1975, when mangy foxes appeared in the northern part of the country. In 1984, mange was observed in most parts of Sweden. The disease was observed to spread rapidly in boreal areas, whereas it spread more slowly in agricultural areas. Mortality due to mange was very high. The duration of the disease before death due to emaciation has been shown experimentally to be over 90 days. An outbreak of fox mange among Arctic foxes (Alopex lagopus) occurred in 1986. The local population of Arctic foxes was caught and successfully treated. The following year, treated foxes were caught again and no signs of disease were found. Sporadic cases of fox mange have also been diagnosed in lynx (Lynx lynx), pine marten (Martes martes) and domestic dogs. Single cases have been observed in other species: wolf (Canis lupus), mountain hare (Lepus timidus), domestic cat and horse. No cases of sarcoptic mange have been recorded in the badger (Meles meles). At present, although fox mange occurs as an epizootic in local populations, the number of foxes has increased again in many parts of Sweden.

An adaptive-management framework for optimal control of hiking near golden eagle nests in Denali National Park

USGS Publications Warehouse

Martin, Julien; Fackler, Paul L.; Nichols, James D.; Runge, Michael C.; McIntyre, Carol L.; Lubow, Bruce L.; McCluskie, Maggie C.; Schmutz, Joel A.

2011-01-01

Unintended effects of recreational activities in protected areas are of growing concern. We used an adaptive-management framework to develop guidelines for optimally managing hiking activities to maintain desired levels of territory occupancy and reproductive success of Golden Eagles (Aquila chrysaetos) in Denali National Park (Alaska, U.S.A.). The management decision was to restrict human access (hikers) to particular nesting territories to reduce disturbance. The management objective was to minimize restrictions on hikers while maintaining reproductive performance of eagles above some specified level. We based our decision analysis on predictive models of site occupancy of eagles developed using a combination of expert opinion and data collected from 93 eagle territories over 20 years. The best predictive model showed that restricting human access to eagle territories had little effect on occupancy dynamics. However, when considering important sources of uncertainty in the models, including environmental stochasticity, imperfect detection of hares on which eagles prey, and model uncertainty, restricting access of territories to hikers improved eagle reproduction substantially. An adaptive management framework such as ours may help reduce uncertainty of the effects of hiking activities on Golden Eagles

Mississippi River Headwaters Reservoirs. Minnesota Master Plan for Public Use Development and Resource Management.

DTIC Science & Technology

1977-12-06

Red Oak Woodchuck• ~~Paper BirchWodhc White Tailed Deer SHRUBS BIRDS Chokecherry Great Blue HeronAlwde Common Egret Dogwood Woodduck HERBS...SHRUBS BIRDS Hazelnut Eagle Chokecherry Hawks Juneberry Great Horned Owl Woodpeckers HERBS Chickadee Hepatica Wren Violet Warblers Solomons Seal Sparrows...Snowshoe Hare N. Red Oak Woodchuck Paper Birch White Tailed Deer SHRUBS BIRDS Chokecherry Great Blue Heron Alder Common Egret Dogwood Woodduck HERBS

77 FR 9170 - Standard Instrument Approach Procedures, and Takeoff Minimums and Obstacle Departure Procedures...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-16

...-NOTAM), and is incorporated by reference in the amendment under 5 U.S.C. 552(a), 1 CFR part 51, and Sec... citation for part 97 continues to read as follows: Authority: 49 U.S.C. 106(g), 40103, 40106, 40113, 40114... LOC RWY 9L, ILS RWY 9L (CAT II), ILS RWY 9L (CAT III), Orig-C 8-Mar-12 IL Chicago Chicago O'Hare Intl...

An Analysis of Security Incidents on the Internet 1989-1995

DTIC Science & Technology

1997-04-07

DeHart, Derek Simmel, and James Stevens. Thanks to the Engineering and Public Policy Department for their support, both intellectually and financially...stated in Chapter 4, the first of these categories, the judgment of CERT@/CC personnel, was given sa- ong weight in determining the scope of an...Coh95] [DSB96] [FIR961 [Fri78] References Derek Atkins, Paul Buis, Chris Hare, Robert Kelley, Carey Nachenberg Anthony B. Nelson, Paul Phillips, Tim

Environmental Assessment of Alternate Training Area Jack Pine Flats Idaho Department of Lands Near Coolin, Idaho

DTIC Science & Technology

2009-05-01

Affected Environment The ROI is within the Eastern Washington -Northern Idaho Interstate Air Quality Control Region. Of the six criteria pollutants...growth. Numerous openings (natural and man-made), wetlands, riparian areas, dry meadow, shrublands, and stands of deciduous trees distributed across... deciduous trees and shrubs or lodge pole pine) to provide food and cover for wintering snowshoe hare. • Denning Cover - generally mature and/or old

Field Evaluation of the Sidestream Sensors for Filter/Separators and Clay Filters.

DTIC Science & Technology

1987-02-01

originally, but only the Atlanta and New York ( JFK ) airports produced suitable test results. At O’Hare (Chicago) Airport, the operator advised the...the JFK Airport installation, every one of the eight test runs terminated prematurely because solids caused pressure drop buildup before any surfactant...about 20 points. In this test period, the high CSS rating also confirmed the activity of the clay. At JFK Airport , the CSS was tested on 27 occasions

Cooperative Analysis of National Bureau of Standards Standard Sample Number 30e (Or-V Steel)

DTIC Science & Technology

1956-04-10

üatioual ?ßureau of g)tanbarbÄ Certificate of ^nalp^ etf Standard Sample 30E Chromium-Vanadium Steel kf mMmJmSmm ««UM ikco^ KMaQ« •• I N<IS<UI H4 «• a... stock , and cannot be furnished. If convenient, we would like to hare reports by February 20. Please include with your report a brief outline of the

Investigation of Crimean-Congo Hemorrhagic Fever and Hemorrhagic Fever with Renal Syndrome in Greece

DTIC Science & Technology

1993-12-20

collect a 24-h urine sample, wich was sent to the laboratory for total protein excretion, electrolytes, uric acid , 3 and creatinine measurements. On...electrolytes, uric acid , total protein, and globulins was also obtained. Urinary comcentrating ability was studied using the protocol of Gyory et al., in...Electrolytes in sera and urine were determined by flame photometry, and creatinine by the method of Hare. Urice acid was determined by a uricase method

Purification and biochemical characterization of a D-galactose binding lectin from Japanese sea hare (Aplysia kurodai) eggs.

PubMed

Kawsar, S M A; Matsumoto, R; Fujii, Y; Yasumitsu, H; Dogasaki, C; Hosono, M; Nitta, K; Hamako, J; Matsui, T; Kojima, N; Ozeki, Y

2009-07-01

A lectin was purified from Japanese sea hare Aplysia kurodai by lactosyl-agarose affinity chromatography. The molecular mass of the lectin was determined to be 56 and 32 kDa by SDS-PAGE under non-reducing and reducing conditions, respectively. It was found to agglutinate trypsinized and glutaraldehyde-fixed rabbit and human erythrocytes in the absence of divalent cations. The lectin exhibited stable thermo-tolerance as it retained hemagglutinating activity for 1 h even at 80 degrees C and showed stability at pH 10. By contrast, it was very sensitive at pH less than 5 and in the presence of the sulfhydryl-group preserving reagent, beta-mercaptoethanol. The hemagglutinating activity by the lectin was specifically inhibited by D-galactose, galacturonic acid, methyl-alpha- and methyl-beta-D-galactopyranoside, lactose, melibiose, and asialofetuin. The association rate constant (k(ass)) and dissociation rate constant (k(diss)) were determined for the lectin to be 4.3 x 10(5) M(-1) x sec(-1) and 2.2 x 10(-3) sec(-1), respectively, using a surface plasmon resonance biosensor. The lectin moderately inhibited cell proliferation in the P388 cell line dose dependently. Interestingly, lectin-treated cells did not show a fragmented DNA ladder as is caused by apoptosis, suggesting that the cell proliferation inhibition was caused by another unknown mechanism.

Deficient behavioral inhibition and anomalous selective attention in a community sample of adolescents with psychopathic traits and low-anxiety traits.

PubMed

Vitale, Jennifer E; Newman, Joseph P; Bates, John E; Goodnight, Jackson; Dodge, Kenneth A; Pettit, Gregory S

2005-08-01

Socialization is the important process by which individuals learn and then effectively apply the rules of appropriate societal behavior. Response modulation is a psychobiological process theorized to aid in socialization by allowing individuals to utilize contextual information to modify ongoing behavior appropriately. Using Hare's (1991) Psychopathy Checklist and the Welsh (1956) anxiety scale, researchers have identified a relatively specific form of a response modulation deficit in low-anxious, Caucasian psychopaths. Preliminary evidence suggests that the Antisocial Process Screening Device (APSD; Frick & Hare, 2001) may be used to identify children with a similar vulnerability. Using a representative community sample of 308 16-year-olds from the Child Development Project (Dodge, Bates, & Pettit, 1990), we tested and corroborated the hypotheses that participants with relatively low anxiety and high APSD scores would display poorer passive avoidance learning and less interference on a spatially separated, picture-word Stroop task than controls. Consistent with hypotheses, the expected group differences in picture-word Stroop interference were found with male and female participants, whereas predicted differences in passive avoidance were specific to male participants. To the extent that response modulation deficits contributing to poor socialization among psychopathic adult offenders also characterize a subgroup of adolescents with mild conduct problems, clarification of the developmental processes that moderate the expression of this vulnerability could inform early interventions.

Determining the metallicity of the solar envelope using seismic inversion techniques

NASA Astrophysics Data System (ADS)

Buldgen, G.; Salmon, S. J. A. J.; Noels, A.; Scuflaire, R.; Dupret, M. A.; Reese, D. R.

2017-11-01

The solar metallicity issue is a long-lasting problem of astrophysics, impacting multiple fields and still subject to debate and uncertainties. While spectroscopy has mostly been used to determine the solar heavy elements abundance, helioseismologists attempted providing a seismic determination of the metallicity in the solar convective envelope. However, the puzzle remains since two independent groups provided two radically different values for this crucial astrophysical parameter. We aim at providing an independent seismic measurement of the solar metallicity in the convective envelope. Our main goal is to help provide new information to break the current stalemate amongst seismic determinations of the solar heavy element abundance. We start by presenting the kernels, the inversion technique and the target function of the inversion we have developed. We then test our approach in multiple hare-and-hounds exercises to assess its reliability and accuracy. We then apply our technique to solar data using calibrated solar models and determine an interval of seismic measurements for the solar metallicity. We show that our inversion can indeed be used to estimate the solar metallicity thanks to our hare-and-hounds exercises. However, we also show that further dependencies in the physical ingredients of solar models lead to a low accuracy. Nevertheless, using various physical ingredients for our solar models, we determine metallicity values between 0.008 and 0.014.

Stratigraphical evidence of late Amazonian periglaciation and glaciation in the Astapus Colles region of Mars

NASA Astrophysics Data System (ADS)

Soare, Richard J.; Osinski, Gordon R.

2009-07-01

Recent modeling of the meteorological conditions during and following times of high obliquity suggests that an icy mantle could have been emplaced in western Utopia Planitia by atmospheric deposition during the late Amazonian period [Costard, F.M., Forget, F., Madeleine, J.B., Soare, R.J., Kargel, J.S., 2008. Lunar Planet. Sci. 39. Abstract 1274; Madeleine, B., Forget, F., Head, J.W., Levrard, B., Montmessin, F., 2007. Lunar Planet. Sci. 38. Abstract 1778]. Astapus Colles (ABa) is a late Amazonian geological unit - located in this hypothesized area of accumulation - that comprises an icy mantle tens of meters thick [Tanaka, K.L., Skinner, J.A., Hare, T.M., 2005. US Geol. Surv. Sci. Invest., Map 2888]. For the most part, this unit drapes the early Amazonian Vastitas Borealis interior unit (ABvi); to a lesser degree it overlies the early Amazonian Vastitas Borealis marginal unit (ABvm) and the early to late Hesperian UP plains unit HBu2 [Tanaka, K.L., Skinner, J.A., Hare, T.M., 2005. US Geol. Surv. Sci. Invest., Map 2888]. Landscapes possibly modified by late-Amazonian periglacial processes [Costard, F.M., Kargel, J.S., 1995. Icarus 114, 93-112; McBride, S.A., Allen, C.C., Bell, M.S., 2005. Lunar Planet. Sci. 36. Abstract 1090; Morgenstern, A., Hauber, E., Reiss, D., van Gasselt, S., Grosse, G., Schirrmeister, L., 2007. J. Geophys. Res. 112, doi:10.1029/2006JE002869. E06010; Seibert, N.M., Kargel, J.S., 2001. Geophys. Res. Lett. 28, 899-902; Soare, R.J., Kargel, J.S., Osinski, G.R., Costard, F., 2007. Icarus 191, 95-112; Soare, R.J., Osinski, G.R., Roehm, C.L., 2008. Earth Planet. Sci. Lett. 272, 382-393] and glacial processes [Milliken, R.E., Mustard, J.F., Goldsby, D.L., 2003. J. Geophys. Res. 108 (E6), doi:10.1029/2002JE002005. 5057; Mustard, J.F., Cooper, C.D., Rifkin, M.K., 2001. Nature 412, 411-414; Tanaka, K.L., Skinner, J.A., Hare, T.M., 2005. US Geol. Surv. Sci. Invest., Map 2888] have been reported within the region. Researchers have assumed that the periglacial and glacial landscapes occur within the same geological unit, the ABa [i.e., Morgenstern, A., Hauber, E., Reiss, D., van Gasselt, S., Grosse, G., Schirrmeister, L., 2007. J. Geophys. Res. 112; doi:10.1029/2006JE002869. E06010; Tanaka, K.L., Skinner, J.A., Hare, T.M., 2005. US Geol. Surv. Sci. Invest., Map 2888]. In this study we use HiRISE (High Resolution Image Science Experiment, Mars Reconnaissance Orbiter) imagery to identify the stratigraphical separation of the two landscapes and show that periglacial landscape modification has occurred in the geological units that underlie the ABa, not in the ABa itself. Moreover, we suggest that the periglacial landscape extends well beyond the perimeter of the ABa and could be the product of "wet" cold-climate processes. These processes involve freeze-thaw cycles and intermittently stable liquid-water at or near the surface. By contrast, we propose that the ABa is a very recent late-Amazonian geological unit formed principally by "dry" cold-climate processes. These processes comprise accumulation (by atmospheric deposition) and ablation (by sublimation).

Chaplaincy at a Crossroads: Fundamentalist Chaplains in a Pluralistic Army

DTIC Science & Technology

2011-03-03

chaplain recalled witnessing “handwringing sessions when our most orthodox brethren [sic] have lamented the possibility of Buddhist, Baha ‟ i , Hare...their religious humanism, how shall they ever deal with chaplains who worship Buddha, Baha ‟u‟llah, or the Guru Maharaji?‟ he asked.”44 Chaplain...46 As a junior chaplain on active duty, I had an eye-opening experience when I deployed with 62nd Medical Group to Somalia in 1993. Early in the

The Impact of Long-Run CRAF Activation Risk on International Routes

DTIC Science & Technology

2011-06-01

CRAF Stage II activations. United Airlines’ Los Angeles ( LAX ) to Tokyo, Japan (NRT) route scored a low .236, while the country risk for United in...0.5969 3.0173 16.5955 CO EWR MUC 0.0038 0.0213 3.0173 16.5955 UA LAX NRT 0.0333 0.2363 4.7173 28.4942 Route Risk Score Ranges - Low: 0 - .5...International Airport LAX – Los Angles International Airport ORD – Chicago O’Hare International Airport SFO – San Francisco International Airport

Studies of Blade Shank Form and Pitch Distribution for Constant-Speed Propellers

DTIC Science & Technology

1945-01-01

Federal »OTernaent wh(> hare a lajH.iaa.te int*r»et therein, and to United *t»*«a clliiena. jit tai*wr. llfc_ altj.and UlecreHon .who if miiilu...the latter —_ effect is ascribed to the stalling characteristics of tha.. _ _ thin profiles. It was also found that objectionable discozi...ofr- propellers, special_attention is given to the effects of overloading, RESTRICTED - — ( NACA TN No. 947 INTRODUCTION The necessity of

Survey of Francisella tularensis in Wild Animals in Japan in Areas Where Tularemia is Endemic.

PubMed

Hotta, Akitoyo; Tanabayashi, Kiyoshi; Fujita, Osamu; Shindo, Junji; Park, Chu-Ho; Kudo, Noboru; Hatai, Hitoshi; Oyamada, Toshifumi; Yamamoto, Yoshie; Takano, Ai; Kawabata, Hiroki; Sharma, Neekun; Uda, Akihiko; Yamada, Akio; Morikawa, Shigeru

2016-09-21

Samples taken from 428 wild animals and 126 ticks, collected from a tularemia-endemic area in Japan between 2005 and 2013, were analyzed for the presence of Francisella tularensis. F. tularensis was isolated from a Japanese hare carcass whereas the samples from live animals and ticks were negative for F. tularensis by real-time PCR. Our results suggest that F. tularensis is still present in Japan although its prevalence is considerably low even in areas where tularemia is endemic.

First report of a parasitic mite, Leptotrombidium (Hypotrombidium) subquadratum (Lawerence) (Acari: Trombiculidae: Trombiculinae), from dogs and children in the Bloemfontein area, South Africa.

PubMed

Heyne, H; Ueckermann, E A; Coetzee, L

2001-06-01

Leptotrombidium subqunadratum larvae were collected for the first time in 1994 from dogs in Bloemfontein. The larvae have been collected annually, during the summer months, over a period of 6-7 years. Previously the only known hosts were scrub hare (Lepus saxatilis) (locality unknown) and short-snouted elephant shrew (Elephantulus brachyrhynchus) (Kruger National Park). These mites cause severe itching and dermatitis in humans and dogs.

Chicago’s O’Hare Runway Configuration Management System (RCMS). Volume 1. Description of the Operational Software,

DTIC Science & Technology

1987-07-01

9 ...Glossary D-i E- Distribution List E-I D. tSl ’S I hec 3 tttt ,"t!<_-Z. :,,’ e ’: :’ :.,", : - ’,,"/ . .>" ",;’ 9 ’ ’:/’,"" ’,,-’¢’..’:, : ,’-.’ ,.-;.;.;- 4...2 Sheets) 23 6 Foreground Program Flowchart (2 Sheets) 25 7 PF-1 Master Auto Panel 27 8 PF-2 Master Panel 28 9 PF-3 Eligible Current

[Depression in Precolumbian Mesoamerican medicine].

PubMed

Rodriguez-Landa, J F; Pulido-Criollo, F; Saavedra, M

To review the concept of depression and its treatment in the context of Precolumbian Mesoamerican medicine. The origins of Precolumbian Mesoamerican medicine (ticiotl) are imprecise, since the theoretical and disease-healing concepts of the times were doubtlessly influenced by magic and religious beliefs. However, the ticiotl was constructed on a 'theory' based on structured information integrated to the world philosophy, which included the social, religious and cultural behavior of the Aztec people. Health was considered a result of the balance between cold-hot polarity. Imbalance caused disease, which in turn produced a dynamic impairment of the body and its relation to the cosmos. Disease could be originated by multiple factors, e.g., by god-sent punishment, or caused by man's evil or by a destiny marked since birth. Depression, among other diseases, was identified in the ticiotl, and was attributed to alterations in the yollotl (heart). It was treated with plants such as quauhyayual, itzauhyatl and xoxocoatl, with animals such as hare, chicken and fish, and with some minerals. Also, recommendations were given to the individual on his life style in a magic-religious context. In Precolumbian Mesoamerican medicine, depression was identified, and therapeutic methods were developed which may be far from the modern medical concept, but at the time fulfilled the function of understanding and recovering the individual's health.

Single-Molecule Unbinding Forces between the Polysaccharide Hyaluronan and Its Binding Proteins.

PubMed

Bano, Fouzia; Tammi, Markku I; Kang, David W; Harris, Edward N; Richter, Ralf P

2018-06-19

The extracellular polysaccharide hyaluronan (HA) is ubiquitous in all vertebrate tissues, where its various functions are encoded in the supramolecular complexes and matrices that it forms with HA-binding proteins (hyaladherins). In tissues, these supramolecular architectures are frequently subjected to mechanical stress, yet how this affects the intermolecular bonding is largely unknown. Here, we used a recently developed single-molecule force spectroscopy platform to analyze and compare the mechanical strength of bonds between HA and a panel of hyaladherins from the Link module superfamily, namely the complex of the proteoglycan aggrecan and cartilage link protein, the proteoglycan versican, the inflammation-associated protein TSG-6, the HA receptor for endocytosis (stabilin-2/HARE), and the HA receptor CD44. We find that the resistance to tensile stress for these hyaladherins correlates with the size of the HA-binding domain. The lowest mean rupture forces are observed for members of the type A subgroup (i.e., with the shortest HA-binding domains; TSG-6 and HARE). In contrast, the mechanical stability of the bond formed by aggrecan in complex with cartilage link protein (two members of the type C subgroup, i.e., with the longest HA-binding domains) and HA is equal or even superior to the high affinity streptavidin⋅biotin bond. Implications for the molecular mechanism of unbinding of HA⋅hyaladherin bonds under force are discussed, which underpin the mechanical properties of HA⋅hyaladherin complexes and HA-rich extracellular matrices. Copyright © 2018 Biophysical Society. Published by Elsevier Inc. All rights reserved.

[Retraction of papers in bioethics: proposal for a paradigmatic case].

PubMed

Herranz Rodríguez, Gonzalo

2011-01-01

The phenomenon of ethically deficient publication in the field of bioethics is practically unknown. In contrast to the numerous articles and regulations on the ethics of biomedical publications, there is a practical absence of articles devoted to consider the nature, types and prevalence of ethically defective publications in the bioethical literature. No regulatory framework for misbehavior in this field has been proposed until now. Certainly, this is a difficult subject. On one side, it is not easy to draw the ethical limits of the freedoms of thought and expression in bioethics, a discipline that flourishes in the open debate of principles, norms, cases, and imaginary scenarios, where the boundaries between rhetoric and misrepresentation are frequently blurred. After showing some examples of minor violations taken from the literature, the author deals with the moral duty to retract fraudulent bioethical articles, especially when they include deliberate distortions of the data or conclusions from published biomedical research. A detailed analysis of a fraudulent article is made (Haring B. ″New Dimensions of Responsible Parenthood. ″ Theological Studies 37, (1976), 120-132), in which an almost systematic distortion of data and opinions of the cited literature has been made. The article, published in a time of intense and critical protest against the encyclical Humanae vitae, pretends to condemn the methods of natural family planning, the only acceptable means to the Pope, on the allegation that those methods were harmful for the embryo and fetus. According to the author, the retraction of Haring's article is necessary.

[Gypsy moth Lymantria dispar L. in the South Urals: Patterns in population dynamics and modelling].

PubMed

Soukhovolsky, V G; Ponomarev, V I; Sokolov, G I; Tarasova, O V; Krasnoperova, P A

2015-01-01

The analysis is conducted on population dynamics of gypsy moth from different habitats of the South Urals. The pattern of cyclic changes in population density is examined, the assessment of temporal conjugation in time series of gypsy moth population dynamics from separate habitats of the South Urals is carried out, the relationships between population density and weather conditions are studied. Based on the results obtained, a statistical model of gypsy moth population dynamics in the South Urals is designed, and estimations are given of regulatory and modifying factors effects on the population dynamics.

Identification of Novel Molecular Targets for Pleckstrin Homology (PH) Domains Found in Oncogenes Implicated in Breast Cancer

DTIC Science & Technology

2008-03-01

roles as a positive regulator of IL- 2 gene induction in T cells (Deckert et al, 1998), NK cell-mediated cytotoxicity (Jevremovic et al, 2001), and FcRI...Identification of a gene encoding a human oxysterol-binding protein-homologue: a potential general molecular marker for blood dissemination of solid...Biol. 6(5), 384-385. Scanlan, MJ, Gout , I, Gordon, CM, Williamson, B, Stockert, E, Gure, AO, Jager, D, Chen, YT, Mackay, A, O’Hare, MJ, and Old LJ

[Fibroadenoma in an accessory breast. A case of polythelia and fibroadenoma in the left breast region and a perivulvar accessory breast].

PubMed

Degrell, I

1979-08-02

The case of a 32-year-old female patient with multiple malformations (hare-lip, polythelia, fibroadenoma in an accessory mammary gland) and independent of these, another fibroadenoma in the breast is reported. The fibroadenoma developing in the accessory breast around the vulva, diagnosed by means of aspiration biopsy cytology, should be payed special attention. This case also confirms the applicability in preoperative diagnostics of aspiration biopsy cytology, a method which has proved to be effective for years.

Utilitarianism.

PubMed

Gillon, R

1985-05-11

In one of a series of British Medical Journal articles on the philosophical foundations of medical ethics, Gillon outlines the pros and cons of utilitarian theories of ethics, which determine the morality of actions by whether or not they increase happiness or decrease suffering. He counters utilitarian claims to have overcome the disadvantages of deontological theories by pointing out flaws in the coherence, justification, and results of utilitarian arguments, as these arguments are exemplified in the writings of Bentham, Mill, and Hare. He observes that many modern utilitarians have overcome problems with their basic theories by accommodating aspects of deontological thinking.

O’Hare International Airport, Chicago Revised Uniform Summary of Surface Weather Observations (RUSSWO). Parts A-F.

DTIC Science & Technology

1984-10-01

O’h6RE IAP IL p STATImN 6.4411 vAlls u WIT BULS TEMPERATURE DEPRESION (P) TOTAL TOTAL 0 1.2 3.4 5.4 7.8 It.0 )@ll.12113.1d 115-1617-11 -~.22 .42 .4 ?.lt...SCRMT jS 1ATCIIYHO RC SUMMARY ATk -F>AT,, S i~JlrMfAf 72 L1 iJCA’IJ-CltAiL IAP IL I. ) AL.E 1 "Tlf ________________ WIT BULB TEMPERATURE DEPRESION (P

Effects of constant immigration on the dynamics and persistence of stable and unstable Drosophila populations

PubMed Central

Dey, Snigdhadip; Joshi, Amitabh

2013-01-01

Constant immigration can stabilize population size fluctuations but its effects on extinction remain unexplored. We show that constant immigration significantly reduced extinction in fruitfly populations with relatively stable or unstable dynamics. In unstable populations with oscillations of amplitude around 1.5 times the mean population size, persistence and constancy were unrelated. Low immigration enhanced persistence without affecting constancy whereas high immigration increased constancy without enhancing persistence. In relatively stable populations with erratic fluctuations of amplitude close to the mean population size, both low and high immigration enhanced persistence. In these populations, the amplitude of fluctuations relative to mean population size went down due to immigration, and their dynamics were altered to low-period cycles. The effects of immigration on the population size distribution and intrinsic dynamics of stable versus unstable populations differed considerably, suggesting that the mechanisms by which immigration reduced extinction risk depended on underlying dynamics in complex ways. PMID:23470546

Presence of Old Individuals in a Population Accelerates and Optimizes the Process of Selection: in silico Experiments.

PubMed

Chistyakov, V A; Denisenko, Y V; Bren, A B

2018-02-01

One of the important components of the concept of aging-phenoptosis (programmed aging) is the notion of aging as an accelerator of evolution having the rank of subconcept. For many reasons, the main being the problematic experimental testing of evolutionary hypotheses, verification of the above-mentioned subconcept can be based primarily on analysis of the internal inconsistency of heuristic models and their correspondence to undisputedly observed facts. To illustrate the acceleration mechanism, and most importantly to structure the evolutionary process in communities that include naturally weakened individuals, V. P. Skulachev offered in 2003 a conceptual model that he later called a "fable about hares". Despite its simplicity, this model has undoubted internal logic. The natural trend in the development of conceptual models is their translation into the language of mathematics. The purpose of the present work was to create a variation of the known multi-agent model "predator-prey" that would allow us to "see" how the presence in the prey population of naturally weakened (old) members stimulates the selection of individuals with traits whose adaptive potential is not devaluated with age. The model (http://homebear.ru/PD) was developed on the Java platform, version 6, NetBeans development environment 8.2. Statistical analysis and preparation of illustrative materials were carried out using environment R, version 3.4.1. The results of numerical experiments set using our model correspond in principle to the provisions of the heuristic model of Skulachev and, consequently, confirm the absence in it of logical contradictions.

Towards a Population Dynamics Theory for Evolutionary Computing: Learning from Biological Population Dynamics in Nature

NASA Astrophysics Data System (ADS)

Ma, Zhanshan (Sam)

In evolutionary computing (EC), population size is one of the critical parameters that a researcher has to deal with. Hence, it was no surprise that the pioneers of EC, such as De Jong (1975) and Holland (1975), had already studied the population sizing from the very beginning of EC. What is perhaps surprising is that more than three decades later, we still largely depend on the experience or ad-hoc trial-and-error approach to set the population size. For example, in a recent monograph, Eiben and Smith (2003) indicated: "In almost all EC applications, the population size is constant and does not change during the evolutionary search." Despite enormous research on this issue in recent years, we still lack a well accepted theory for population sizing. In this paper, I propose to develop a population dynamics theory forEC with the inspiration from the population dynamics theory of biological populations in nature. Essentially, the EC population is considered as a dynamic system over time (generations) and space (search space or fitness landscape), similar to the spatial and temporal dynamics of biological populations in nature. With this conceptual mapping, I propose to 'transplant' the biological population dynamics theory to EC via three steps: (i) experimentally test the feasibility—whether or not emulating natural population dynamics improves the EC performance; (ii) comparatively study the underlying mechanisms—why there are improvements, primarily via statistical modeling analysis; (iii) conduct theoretical analysis with theoretical models such as percolation theory and extended evolutionary game theory that are generally applicable to both EC and natural populations. This article is a summary of a series of studies we have performed to achieve the general goal [27][30]-[32]. In the following, I start with an extremely brief introduction on the theory and models of natural population dynamics (Sections 1 & 2). In Sections 4 to 6, I briefly discuss three categories of population dynamics models: deterministic modeling with Logistic chaos map as an example, stochastic modeling with spatial distribution patterns as an example, as well as survival analysis and extended evolutionary game theory (EEGT) modeling. Sample experiment results with Genetic algorithms (GA) are presented to demonstrate the applications of these models. The proposed EC population dynamics approach also makes survival selection largely unnecessary or much simplified since the individuals are naturally selected (controlled) by the mathematical models for EC population dynamics.

Fine-scale population dynamics in a marine fish species inferred from dynamic state-space models.

PubMed

Rogers, Lauren A; Storvik, Geir O; Knutsen, Halvor; Olsen, Esben M; Stenseth, Nils C

2017-07-01

Identifying the spatial scale of population structuring is critical for the conservation of natural populations and for drawing accurate ecological inferences. However, population studies often use spatially aggregated data to draw inferences about population trends and drivers, potentially masking ecologically relevant population sub-structure and dynamics. The goals of this study were to investigate how population dynamics models with and without spatial structure affect inferences on population trends and the identification of intrinsic drivers of population dynamics (e.g. density dependence). Specifically, we developed dynamic, age-structured, state-space models to test different hypotheses regarding the spatial structure of a population complex of coastal Atlantic cod (Gadus morhua). Data were from a 93-year survey of juvenile (age 0 and 1) cod sampled along >200 km of the Norwegian Skagerrak coast. We compared two models: one which assumes all sampled cod belong to one larger population, and a second which assumes that each fjord contains a unique population with locally determined dynamics. Using the best supported model, we then reconstructed the historical spatial and temporal dynamics of Skagerrak coastal cod. Cross-validation showed that the spatially structured model with local dynamics had better predictive ability. Furthermore, posterior predictive checks showed that a model which assumes one homogeneous population failed to capture the spatial correlation pattern present in the survey data. The spatially structured model indicated that population trends differed markedly among fjords, as did estimates of population parameters including density-dependent survival. Recent biomass was estimated to be at a near-record low all along the coast, but the finer scale model indicated that the decline occurred at different times in different regions. Warm temperatures were associated with poor recruitment, but local changes in habitat and fishing pressure may have played a role in driving local dynamics. More generally, we demonstrated how state-space models can be used to test evidence for population spatial structure based on survey time-series data. Our study shows the importance of considering spatially structured dynamics, as the inferences from such an approach can lead to a different ecological understanding of the drivers of population declines, and fundamentally different management actions to restore populations. © 2017 The Authors. Journal of Animal Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society.

The Laurencia Paradox: An Endless Source of Chemodiversity.

PubMed

Harizani, Maria; Ioannou, Efstathia; Roussis, Vassilios

Nature, the most prolific source of biological and chemical diversity, has provided mankind with treatments for health problems since ancient times and continues to be the most promising reservoir of bioactive chemicals for the development of modern drugs. In addition to the terrestrial organisms that still remain a promising source of new bioactive metabolites, the marine environment, covering approximately 70% of the Earth's surface and containing a largely unexplored biodiversity, offers an enormous resource for the discovery of novel compounds. According to the MarinLit database, more than 27,000 metabolites from marine macro- and microorganisms have been isolated to date providing material and key structures for the development of new products in the pharmaceutical, food, cosmeceutical, chemical, and agrochemical sectors. Algae, which thrive in the euphotic zone, were among the first marine organisms that were investigated as sources of food, nutritional supplements, soil fertilizers, and bioactive metabolites.Red algae of the genus Laurencia are accepted unanimously as one of the richest sources of new secondary metabolites. Their cosmopolitan distribution, along with the chemical variation influenced to a significant degree by environmental and genetic factors, have resulted in an endless parade of metabolites, often featuring multiple halogenation sites.The present contribution, covering the literature until August 2015, offers a comprehensive view of the chemical wealth and the taxonomic problems currently impeding chemical and biological investigations of the genus Laurencia. Since mollusks feeding on Laurencia are, in many cases, bioaccumulating, and utilize algal metabolites as chemical weaponry against natural enemies, metabolites of postulated dietary origin of sea hares that feed on Laurencia species are also included in the present review. Altogether, 1047 secondary metabolites, often featuring new carbocyclic skeletons, have been included.The chapter addresses: (1) the "Laurencia complex", the botanical description and the growth and population dynamics of the genus, as well as its chemical diversity and ecological relations; (2) the secondary metabolites, which are organized according to their chemical structures and are classified into sesquiterpenes, diterpenes, triterpenes, acetogenins, indoles, aromatic compounds, steroids, and miscellaneous compounds, as well as their sources of isolation which are depicted in tabulated form, and (3) the biological activity organized according to the biological target and the ecological functions of Laurencia metabolites.

Obesity, stigma, and responsibility in health care: A synthesis of qualitative studies

PubMed Central

Ulriksen, Kjersti

2011-01-01

Objective To synthesize research findings on experiences and attitudes about obesity and stigma in health care. Methods We compiled qualitative studies and applied Noblitt & Hare's meta ethnography to identify, translate, and summarize across studies. Thirteen qualitative studies on experiences and attitudes about obesity and stigma in health care settings were identified and included. Results The study reveals how stigmatizing attitudes are enacted by health care providers and perceived by patients with obesity. Second-order analysis demonstrated that apparently appropriate advice can be perceived as patronizing by patients with obesity. Furthermore, health care providers indicate that abnormal bodies cannot be incorporated in the medical systems—exclusion of patients with obesity consequently happens. Finally, customary standards for interpersonal respect are legitimately surpassed, and patients with obesity experience contempt as if deserved. Third-order analysis revealed conflicting views between providers and patients with obesity on responsibility, whereas internalized stigma made patients vulnerable for accepting a negative attribution. A theoretical elaboration relates the issues of stigma with those of responsibility. Conclusion Contradictory views on patients’ responsibility, efforts, knowledge, and motivation merge to internalization of stigma, thereby obstructing healthy coping and collaboration and creating negative contexts for empowerment, self-efficacy, and weight management. Professionals need to develop their awareness for potentially stigmatizing attitudes towards vulnerable patient populations. PMID:22121389

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

ADVANCE [Advanced Driver and Vehicle Advisory Navigation ConcEpt] was a public/private partnership conceived and developed by four founding parties. The founding parties include the Federal Highway Administration (FHWA), the Illinois Department of Transportation (IDOT), the University of Illinois at Chicago and Northwestern University operating together under the auspices of the Illinois Universities Transportation Research Consortium (IUTRC), and Motorola, Inc. The major responsibilities of each party are fully described in the Project agreement. Subsequently, these four were joined on the Steering Committee by the American Automobile Association (AAA). This unique blending of public sector, private sector and university interests, augmented bymore » more than two dozen other private sector participants, provided a strong set of resources for ADVANCE. The ADVANCE test area covered over 300 square miles including portions of the City of Chicago and 40 northwest suburban communities. The Project encompasses the high growth areas adjacent to O`Hare International Airport, the Schaumbura/Hoffman Estates office and retail complexes, and the Lake-Cook Road development corridor. It also includes major sports and entertainment complexes such as the Arlington International Racecourse and the Rosemont Horizon. The population in the area is more than 750,000. This volume provides a summary of the insights and achievements made as a result of this field test, and selected appendices containing more detailed information.« less

Olive Fruit Fly (Bactrocera oleae) Population Dynamics in the Eastern Mediterranean: Influence of Exogenous Uncertainty on a Monophagous Frugivorous Insect

PubMed Central

Ordano, Mariano; Engelhard, Izhar; Rempoulakis, Polychronis; Nemny-Lavy, Esther; Blum, Moshe; Yasin, Sami; Lensky, Itamar M.; Papadopoulos, Nikos T.; Nestel, David

2015-01-01

Despite of the economic importance of the olive fly (Bactrocera oleae) and the large amount of biological and ecological studies on the insect, the factors driving its population dynamics (i.e., population persistence and regulation) had not been analytically investigated until the present study. Specifically, our study investigated the autoregressive process of the olive fly populations, and the joint role of intrinsic and extrinsic factors molding the population dynamics of the insect. Accounting for endogenous dynamics and the influences of exogenous factors such as olive grove temperature, the North Atlantic Oscillation and the presence of potential host fruit, we modeled olive fly populations in five locations in the Eastern Mediterranean region. Our models indicate that the rate of population change is mainly shaped by first and higher order non-monotonic, endogenous dynamics (i.e., density-dependent population feedback). The olive grove temperature was the main exogenous driver, while the North Atlantic Oscillation and fruit availability acted as significant exogenous factors in one of the five populations. Seasonal influences were also relevant for three of the populations. In spite of exogenous effects, the rate of population change was fairly stable along time. We propose that a special reproductive mechanism, such as reproductive quiescence, allows populations of monophagous fruit flies such as the olive fly to remain stable. Further, we discuss how weather factors could impinge constraints on the population dynamics at the local level. Particularly, local temperature dynamics could provide forecasting cues for management guidelines. Jointly, our results advocate for establishing monitoring programs and for a major focus of research on the relationship between life history traits and populations dynamics. PMID:26010332

Endogenous attention modulates early selective attention in psychopathy: An ERP investigation.

PubMed

Krusemark, Elizabeth A; Kiehl, Kent A; Newman, Joseph P

2016-10-01

Psychopathic individuals are prone to act on urges without adequate consideration of future consequences or the rights of other individuals. One interpretation of this behavior is that it reflects abnormal selective attention (i.e., a failure to process information that is incongruent with their primary focus of attention; Hiatt, Schmitt, & Newman, Neuropsychology, 18, 50-59, 2004). Unfortunately, it is unclear whether this selective attention abnormality reflects top-down endogenous influences, such as the strength or specificity of attention focus (i.e., top-down set) apart from other, more exogenous (bottom-up), effects on attention. To explore this question, we used an early visual event-related potential (N2pc) in combination with a modified visual search task designed to assess the effect of early endogenous (i.e., top-down) attention on the processing of set-congruent information. The task was administered to a sample of 70 incarcerated adult males, who were assigned to high, intermediate, and low psychopathy groups using Hare's Psychopathy Checklist-Revised (Hare, 2003). Based on the assumption that their failure to process set-incongruent information reflects the exaggerated effects of endogenous attention, we predicted that participants with high psychopathy scores would show an exaggerated N2pc response to set-congruent information. The results supported the hypothesis and provide novel electrophysiological evidence that psychopathy is associated with exaggerated endogenous attention effects during early stages of processing. Further research is needed to examine the implications of this finding for the well-established failure of psychopathic individuals to process set-incongruent information and inhibit inappropriate responses.

Comparison of virulence of Francisella tularensis ssp. holarctica genotypes B.12 and B.FTNF002-00.

PubMed

Kreizinger, Zsuzsa; Erdélyi, Károly; Felde, Orsolya; Fabbi, Massimo; Sulyok, Kinga M; Magyar, Tibor; Gyuranecz, Miklós

2017-02-10

Two main genetic groups (B.12 and B.FTNF002-00) of Francisella tularensis ssp. holarctica are endemic in Europe. The B.FTNF002-00 group proved to be dominant in Western European countries, while strains of the B.12 group were isolated mainly in Northern, Central and Eastern Europe. The clinical course of tularemia in the European brown hare (Lepus europaeus) also shows distinct patterns according to the geographical area. Acute course of the disease is observed in hares in Western European countries, while signs of sub-acute or chronic infection are more frequently detected in the eastern part of the continent. The aim of the present study was to examine whether there is any difference in the virulence of the strains belonging to the B.FTNF002-00 and B.12 genetic clades. Experimental infection of Fischer 344 rats was performed by intra-peritoneal injection of three dilutions of a Hungarian (B.12 genotype) and an Italian (B.FTNF002-00 genotype) F. tularensis ssp. holarctica strain. Moderate difference was observed in the virulence of the two genotypes. Significant differences were observed in total weight loss values and scores of clinical signs between the two genotypes with more rats succumbing to tularemia in groups infected with the B.FTNF002-00 genotype. Results of the experimental infection are consistent with previous clinical observations and pathological studies suggesting that F. tularensis ssp. holarctica genotype B.FTNF002-00 has higher pathogenic potential than the B.12 genotype.

Defense through sensory inactivation: sea hare ink reduces sensory and motor responses of spiny lobsters to food odors.

PubMed

Love-Chezem, Tiffany; Aggio, Juan F; Derby, Charles D

2013-04-15

Antipredator defenses are ubiquitous and diverse. Ink secretion of sea hares (Aplysia) is an antipredator defense acting through the chemical senses of predators by different mechanisms. The most common mechanism is ink acting as an unpalatable repellent. Less common is ink secretion acting as a decoy (phagomimic) that misdirects predators' attacks. In this study, we tested another possible mechanism--sensory inactivation--in which ink inactivates the predator's reception of food odors associated with would-be prey. We tested this hypothesis using spiny lobsters, Panulirus argus, as model predators. Ink secretion is composed of two glandular products, one being opaline, a viscous substance containing concentrations of hundreds of millimolar of total free amino acids. Opaline sticks to antennules, mouthparts and other chemosensory appendages of lobsters, physically blocking access of food odors to the predator's chemosensors, or over-stimulating (short term) and adapting (long term) the chemosensors. We tested the sensory inactivation hypotheses by treating the antennules with opaline and mimics of its physical and/or chemical properties. We compared the effects of these treatments on responses to a food odor for chemoreceptor neurons in isolated antennules, as a measure of effect on chemosensory input, and for antennular motor responses of intact lobsters, as a measure of effect on chemically driven motor behavior. Our results indicate that opaline reduces the output of chemosensors by physically blocking reception of and response to food odors, and this has an impact on motor responses of lobsters. This is the first experimental demonstration of inactivation of peripheral sensors as an antipredatory defense.

The influence of sense-contingent argument structure frequencies on ambiguity resolution in aphasia.

PubMed

Huck, Anneline; Thompson, Robin L; Cruice, Madeline; Marshall, Jane

2017-06-01

Verbs with multiple senses can show varying argument structure frequencies, depending on the underlying sense. When acknowledge is used to mean 'recognise', it takes a direct object (DO), but when it is used to mean 'admit' it prefers a sentence complement (SC). The purpose of this study was to investigate whether people with aphasia (PWA) can exploit such meaning-structure probabilities during the reading of temporarily ambiguous sentences, as demonstrated for neurologically healthy individuals (NHI) in a self-paced reading study (Hare et al., 2003). Eleven people with mild or moderate aphasia and eleven neurologically healthy control participants read sentences while their eyes were tracked. Using adapted materials from the study by Hare et al. target sentences containing an SC structure (e.g. He acknowledged (that) his friends would probably help him a lot) were presented following a context prime that biased either a direct object (DO-bias) or sentence complement (SC-bias) reading of the verbs. Half of the stimuli sentences did not contain that so made the post verbal noun phrase (his friends) structurally ambiguous. Both groups of participants were influenced by structural ambiguity as well as by the context bias, indicating that PWA can, like NHI, use their knowledge of a verb's sense-based argument structure frequency during online sentence reading. However, the individuals with aphasia showed delayed reading patterns and some individual differences in their sensitivity to context and ambiguity cues. These differences compared to the NHI may contribute to difficulties in sentence comprehension in aphasia. Copyright © 2017 Elsevier Ltd. All rights reserved.

Examining the maintenance and generalization effects of repeated practice: A comparison of three interventions.

PubMed

Ardoin, Scott P; Binder, Katherine S; Zawoyski, Andrea M; Foster, Tori E

2018-06-01

Repeated reading (RR) procedures are consistent with the procedures recommended by Haring and Eaton's (1978) Instructional Hierarchy (IH) for promoting students' fluent responding to newly learned stimuli. It is therefore not surprising that an extensive body of literature exists, which supports RR as an effective practice for promoting students' reading fluency of practiced passages. Less clear, however, is the extent to which RR helps students read the words practiced in an intervention passage when those same words are presented in a new passage. The current study employed randomized control design procedures to examine the maintenance and generalization effects of three interventions that were designed based upon Haring and Eaton's (1978) IH. Across four days, students either practiced reading (a) the same passage seven times (RR+RR), (b) one passage four times and three passages each once (RR+Guided Wide Reading [GWR]), or (c) seven passages each once (GWR+GWR). Students participated in the study across 2weeks, with intervention being provided on a different passage set each week. All passages practiced within a week, regardless of condition, contained four target low frequency and four high frequency words. Across the 130 students for whom data were analyzed, results indicated that increased opportunities to practice words led to greater maintenance effects when passages were read seven days later but revealed minimal differences across conditions in students' reading of target words presented within a generalization passage. Copyright © 2018 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

A New Understanding of Psychopathy: The Contribution of Phenomenological Psychopathology.

PubMed

Englebert, Jérôme

2015-01-01

The objective of this study is to present a theoretical paper about a clinical issue. Our aim is to propose some clinical and semiological considerations for a psychopathological conception of psychopathy. We will discuss several major theoretical works dedicated to this nosographic entity (mainly those of Schneider [Psychopathic Personalities (1923). London, Cassell, 1950], Cleckley [The Mask of Sanity. St. Louis, Mosby, 1941] and Hare [The Hare Psychopathy Checklist - Revised Manual, ed 2. Toronto, Multi-Health Systems, 2003]). We will also examine a significant issue raised by Cooke et al. [Psychol Assess 2001;13:171-188; J Person Disord 2004;18:337-357; Br J Psychiatry Suppl 2007;49:s39-s50; Int J Forensic Ment Health 2012;11:242-252], namely whether psychopathic functioning is consistently related to antisocial behavior. This theoretical essay is informed by clinical situations (involving psychopaths who were interviewed in prison or in forensic centers). The method applied a phenomenological psychopathology analysis to the clinical material. We first compare Binswanger's conception of mania with psychopathic functioning. Patient behavior is similar, but there is a difference related to the dialectic between the ego and the alter ego. A patient with mania has a fundamental crisis of the ego, which a psychopath does not have. A second finding of our investigations concerns emotions and the adaptive dimension of the psychopathic disorder. An epistemological discussion of the concept of emotions reveals that psychopaths are competent in the management of emotional stimuli, which confers a psychological advantage upon them. © 2015 S. Karger AG, Basel.

Population Dynamics of Genetic Regulatory Networks

NASA Astrophysics Data System (ADS)

Braun, Erez

2005-03-01

Unlike common objects in physics, a biological cell processes information. The cell interprets its genome and transforms the genomic information content, through the action of genetic regulatory networks, into proteins which in turn dictate its metabolism, functionality and morphology. Understanding the dynamics of a population of biological cells presents a unique challenge. It requires to link the intracellular dynamics of gene regulation, through the mechanism of cell division, to the level of the population. We present experiments studying adaptive dynamics of populations of genetically homogeneous microorganisms (yeast), grown for long durations under steady conditions. We focus on population dynamics that do not involve random genetic mutations. Our experiments follow the long-term dynamics of the population distributions and allow to quantify the correlations among generations. We focus on three interconnected issues: adaptation of genetically homogeneous populations following environmental changes, selection processes on the population and population variability and expression distributions. We show that while the population exhibits specific short-term responses to environmental inputs, it eventually adapts to a robust steady-state, largely independent of external conditions. Cycles of medium-switch show that the adapted state is imprinted in the population and that this memory is maintained for many generations. To further study population adaptation, we utilize the process of gene recruitment whereby a gene naturally regulated by a specific promoter is placed under a different regulatory system. This naturally occurring process has been recognized as a major driving force in evolution. We have recruited an essential gene to a foreign regulatory network and followed the population long-term dynamics. Rewiring of the regulatory network allows us to expose their complex dynamics and phase space structure.

Fundamental Parameters of Main-Sequence Stars in an Instant with Machine Learning

NASA Astrophysics Data System (ADS)

Bellinger, Earl P.; Angelou, George C.; Hekker, Saskia; Basu, Sarbani; Ball, Warrick H.; Guggenberger, Elisabeth

2016-10-01

Owing to the remarkable photometric precision of space observatories like Kepler, stellar and planetary systems beyond our own are now being characterized en masse for the first time. These characterizations are pivotal for endeavors such as searching for Earth-like planets and solar twins, understanding the mechanisms that govern stellar evolution, and tracing the dynamics of our Galaxy. The volume of data that is becoming available, however, brings with it the need to process this information accurately and rapidly. While existing methods can constrain fundamental stellar parameters such as ages, masses, and radii from these observations, they require substantial computational effort to do so. We develop a method based on machine learning for rapidly estimating fundamental parameters of main-sequence solar-like stars from classical and asteroseismic observations. We first demonstrate this method on a hare-and-hound exercise and then apply it to the Sun, 16 Cyg A and B, and 34 planet-hosting candidates that have been observed by the Kepler spacecraft. We find that our estimates and their associated uncertainties are comparable to the results of other methods, but with the additional benefit of being able to explore many more stellar parameters while using much less computation time. We furthermore use this method to present evidence for an empirical diffusion-mass relation. Our method is open source and freely available for the community to use.6

The baker’s map with a convex hole

NASA Astrophysics Data System (ADS)

Clark, Lyndsey; Hare, Kevin G.; Sidorov, Nikita

2018-07-01

We consider the baker’s map B on the unit square X and an open convex set which we regard as a hole. The survivor set is defined as the set of all points in X whose B-trajectories are disjoint from H. The main purpose of this paper is to study holes H for which (dimension traps) as well as those for which any periodic trajectory of B intersects (cycle traps). We show that any H which lies in the interior of X is not a dimension trap. This means that, unlike the doubling map and other one-dimensional examples, we can have for H whose Lebesgue measure is arbitrarily close to one. Also, we describe holes which are dimension or cycle traps, critical in the sense that if we consider a strictly convex subset, then the corresponding property in question no longer holds. We also determine such that for all convex H whose Lebesgue measure is less than δ. This paper may be seen as a first extension of our work begun in Clark (2016 Discrete Continuous Dyn. Syst. A 6 1249–69 Clark 2016 PhD Dissertation The University of Manchester; Glendinning and Sidorov 2015 Ergod. Theor. Dynam. Syst. 35 1208–28 Hare and Sidorov 2014 Mon.hefte Math. 175 347–65 Sidorov 2014 Acta Math. Hung. 143 298–312) to higher dimensions.

An individual-based model of zebrafish population dynamics accounting for energy dynamics.

PubMed

Beaudouin, Rémy; Goussen, Benoit; Piccini, Benjamin; Augustine, Starrlight; Devillers, James; Brion, François; Péry, Alexandre R R

2015-01-01

Developing population dynamics models for zebrafish is crucial in order to extrapolate from toxicity data measured at the organism level to biological levels relevant to support and enhance ecological risk assessment. To achieve this, a dynamic energy budget for individual zebrafish (DEB model) was coupled to an individual based model of zebrafish population dynamics (IBM model). Next, we fitted the DEB model to new experimental data on zebrafish growth and reproduction thus improving existing models. We further analysed the DEB-model and DEB-IBM using a sensitivity analysis. Finally, the predictions of the DEB-IBM were compared to existing observations on natural zebrafish populations and the predicted population dynamics are realistic. While our zebrafish DEB-IBM model can still be improved by acquiring new experimental data on the most uncertain processes (e.g. survival or feeding), it can already serve to predict the impact of compounds at the population level.

An Individual-Based Model of Zebrafish Population Dynamics Accounting for Energy Dynamics

PubMed Central

Beaudouin, Rémy; Goussen, Benoit; Piccini, Benjamin; Augustine, Starrlight; Devillers, James; Brion, François; Péry, Alexandre R. R.

2015-01-01

Developing population dynamics models for zebrafish is crucial in order to extrapolate from toxicity data measured at the organism level to biological levels relevant to support and enhance ecological risk assessment. To achieve this, a dynamic energy budget for individual zebrafish (DEB model) was coupled to an individual based model of zebrafish population dynamics (IBM model). Next, we fitted the DEB model to new experimental data on zebrafish growth and reproduction thus improving existing models. We further analysed the DEB-model and DEB-IBM using a sensitivity analysis. Finally, the predictions of the DEB-IBM were compared to existing observations on natural zebrafish populations and the predicted population dynamics are realistic. While our zebrafish DEB-IBM model can still be improved by acquiring new experimental data on the most uncertain processes (e.g. survival or feeding), it can already serve to predict the impact of compounds at the population level. PMID:25938409

The impact of rapid evolution on population dynamics in the wild: experimental test of eco-evolutionary dynamics.

PubMed

Turcotte, Martin M; Reznick, David N; Hare, J Daniel

2011-11-01

Rapid evolution challenges the assumption that evolution is too slow to impact short-term ecological dynamics. This insight motivates the study of 'Eco-Evolutionary Dynamics' or how evolution and ecological processes reciprocally interact on short time scales. We tested how rapid evolution impacts concurrent population dynamics using an aphid (Myzus persicae) and an undomesticated host (Hirschfeldia incana) in replicated wild populations. We manipulated evolvability by creating non-evolving (single clone) and potentially evolving (two-clone) aphid populations that contained genetic variation in intrinsic growth rate. We observed significant evolution in two-clone populations whether or not they were exposed to predators and competitors. Evolving populations grew up to 42% faster and attained up to 67% higher density, compared with non-evolving control populations but only in treatments exposed to competitors and predators. Increased density also correlates with relative fitness of competing clones suggesting a full eco-evolutionary dynamic cycle defined as reciprocal interactions between evolution and density. © 2011 Blackwell Publishing Ltd/CNRS.

Experimental test of an eco-evolutionary dynamic feedback loop between evolution and population density in the green peach aphid.

PubMed

Turcotte, Martin M; Reznick, David N; Daniel Hare, J

2013-05-01

An eco-evolutionary feedback loop is defined as the reciprocal impacts of ecology on evolutionary dynamics and evolution on ecological dynamics on contemporary timescales. We experimentally tested for an eco-evolutionary feedback loop in the green peach aphid, Myzus persicae, by manipulating initial densities and evolution. We found strong evidence that initial aphid density alters the rate and direction of evolution, as measured by changes in genotype frequencies through time. We also found that evolution of aphids within only 16 days, or approximately three generations, alters the rate of population growth and predicts density compared to nonevolving controls. The impact of evolution on population dynamics also depended on density. In one evolution treatment, evolution accelerated population growth by up to 10.3% at high initial density or reduced it by up to 6.4% at low initial density. The impact of evolution on population growth was as strong as or stronger than that caused by a threefold change in intraspecific density. We found that, taken together, ecological condition, here intraspecific density, alters evolutionary dynamics, which in turn alter concurrent population growth rate (ecological dynamics) in an eco-evolutionary feedback loop. Our results suggest that ignoring evolution in studies predicting population dynamics might lead us to over- or underestimate population density and that we cannot predict the evolutionary outcome within aphid populations without considering population size.

Population dynamics of HIV-1 inferred from gene sequences.

PubMed Central

Grassly, N C; Harvey, P H; Holmes, E C

1999-01-01

A method for the estimation of population dynamic history from sequence data is described and used to investigate the past population dynamics of HIV-1 subtypes A and B. Using both gag and env gene alignments the effective population size of each subtype is estimated and found to be surprisingly small. This may be a result of the selective sweep of mutations through the population, or may indicate an important role of genetic drift in the fixation of mutations. The implications of these results for the spread of drug-resistant mutations and transmission dynamics, and also the roles of selection and recombination in shaping HIV-1 genetic diversity, are discussed. A larger estimated effective population size for subtype A may be the result of differences in time of origin, transmission dynamics, and/or population structure. To investigate the importance of population structure a model of population subdivision was fitted to each subtype, although the improvement in likelihood was found to be nonsignificant. PMID:9927440

Effects of spatial structure of population size on the population dynamics of barnacles across their elevational range.

PubMed

Fukaya, Keiichi; Okuda, Takehiro; Nakaoka, Masahiro; Noda, Takashi

2014-11-01

Explanations for why population dynamics vary across the range of a species reflect two contrasting hypotheses: (i) temporal variability of populations is larger in the centre of the range compared to the margins because overcompensatory density dependence destabilizes population dynamics and (ii) population variability is larger near the margins, where populations are more susceptible to environmental fluctuations. In both of these hypotheses, positions within the range are assumed to affect population variability. In contrast, the fact that population variability is often related to mean population size implies that the spatial structure of the population size within the range of a species may also be a useful predictor of the spatial variation in temporal variability of population size over the range of the species. To explore how population temporal variability varies spatially and the underlying processes responsible for the spatial variation, we focused on the intertidal barnacle Chthamalus dalli and examined differences in its population dynamics along the tidal levels it inhabits. Changes in coverage of barnacle populations were monitored for 10.5 years at 25 plots spanning the elevational range of this species. Data were analysed by fitting a population dynamics model to estimate the effects of density-dependent and density-independent processes on population growth. We also examined the temporal mean-variance relationship of population size with parameters estimated from the population dynamics model. We found that the relative variability of populations tended to increase from the centre of the elevational range towards the margins because of an increase in the magnitude of stochastic fluctuations of growth rates. Thus, our results supported hypothesis (2). We also found that spatial variations in temporal population variability were well characterized by Taylor's power law, the relative population variability being inversely related to the mean population size. Results suggest that understanding the population dynamics of a species over its range may be facilitated by taking the spatial structure of population size into account as well as by considering changes in population processes as a function of position within the range of the species. © 2014 The Authors. Journal of Animal Ecology © 2014 British Ecological Society.

Remote Sensing Data Analytics for Planetary Science with PlanetServer/EarthServer

NASA Astrophysics Data System (ADS)

Rossi, Angelo Pio; Figuera, Ramiro Marco; Flahaut, Jessica; Martinot, Melissa; Misev, Dimitar; Baumann, Peter; Pham Huu, Bang; Besse, Sebastien

2016-04-01

Planetary Science datasets, beyond the change in the last two decades from physical volumes to internet-accessible archives, still face the problem of large-scale processing and analytics (e.g. Rossi et al., 2014, Gaddis and Hare, 2015). PlanetServer, the Planetary Science Data Service of the EC-funded EarthServer-2 project (#654367) tackles the planetary Big Data analytics problem with an array database approach (Baumann et al., 2014). It is developed to serve a large amount of calibrated, map-projected planetary data online, mainly through Open Geospatial Consortium (OGC) Web Coverage Processing Service (WCPS) (e.g. Rossi et al., 2014; Oosthoek et al., 2013; Cantini et al., 2014). The focus of the H2020 evolution of PlanetServer is still on complex multidimensional data, particularly hyperspectral imaging and topographic cubes and imagery. In addition to hyperspectral and topographic from Mars (Rossi et al., 2014), the use of WCPS is applied to diverse datasets on the Moon, as well as Mercury. Other Solar System Bodies are going to be progressively available. Derived parameters such as summary products and indices can be produced through WCPS queries, as well as derived imagery colour combination products, dynamically generated and accessed also through OGC Web Coverage Service (WCS). Scientific questions translated into queries can be posed to a large number of individual coverages (data products), locally, regionally or globally. The new PlanetServer system uses the the Open Source Nasa WorldWind (e.g. Hogan, 2011) virtual globe as visualisation engine, and the array database Rasdaman Community Edition as core server component. Analytical tools and client components of relevance for multiple communities and disciplines are shared across service such as the Earth Observation and Marine Data Services of EarthServer. The Planetary Science Data Service of EarthServer is accessible on http://planetserver.eu. All its code base is going to be available on GitHub, on https://github.com/planetserver References: Baumann, P., et al. (2015) Big Data Analytics for Earth Sciences: the EarthServer approach, International Journal of Digital Earth, doi: 10.1080/17538947.2014.1003106. Cantini, F. et al. (2014) Geophys. Res. Abs., Vol. 16, #EGU2014-3784. Gaddis, L., and T. Hare (2015), Status of tools and data for planetary research, Eos, 96, dos: 10.1029/2015EO041125. Hogan, P., 2011. NASA World Wind: Infrastructure for Spatial Data. Technical report. Proceedings of the 2nd International Conference on Computing for Geospatial Research & Applications ACM. Oosthoek, J.H.P, et al. (2013) Advances in Space Research. doi: 10.1016/j.asr.2013.07.002. Rossi, A. P., et al. (2014) PlanetServer/EarthServer: Big Data analytics in Planetary Science. Geophysical Research Abstracts, Vol. 16, #EGU2014-5149.

Geographic variation in density-dependent dynamics impacts the synchronizing effect of dispersal and regional stochasticity

Treesearch

Andrew M. Liebhold; Derek M. Johnson; Ottar N. Bj& #248rnstad

2006-01-01

Explanations for the ubiquitous presence of spatially synchronous population dynamics have assumed that density-dependent processes governing the dynamics of local populations are identical among disjunct populations, and low levels of dispersal or small amounts of regionalized stochasticity ("Moran effect") can act to synchronize populations. In this study...

Cultivating nursing leadership for our envisioned future.

PubMed

Galuska, Lee A

2012-01-01

Nurses have been called upon to lead and partner in the transformation of health care. Leadership is a component of the scope of nursing practice; however, the optimal approach to development of leadership competency has not been established. A metasynthesis of qualitative studies on leadership development was conducted to enhance an understanding of conditions that nurses reported to support or hinder their development as leaders. Noblit and Hare's approach was used for the metasynthesis process. Three overarching themes emerged. Opportunity structure, the relationship factor, and organizational culture are essential factors contributing to the successful cultivation of leadership competencies in nurses.

Rapid Response R&D for the Propulsion Directorate. Delivery Order 0019: Advanced Alternative Energy Technologies, Subtask: Life Cycle Greenhouse Gas Analysis of Advanced Jet Propulsion Fuels: Fischer-Tropsch Based SPK-1 Case Study

DTIC Science & Technology

2011-09-01

carry finished jet fuel from the CBTL facility. The pipeline connects the CBTL facility to a petroleum refinery located in Wood River, Illinois...Under Option 1, all the blended jet fuel is transported via pipeline from the refinery in Wood River to Chicago’s O’Hare airport. Under Option 2...shipping F-T jet fuel to a refinery in Wood River, Illinois (near St. Louis, Missouri) for blending and final transport of the blended jet fuel to

Adaptive Liquid Crystal TV Based Joint Transform Correlator as Applied to Real-Time Pattern Recognition

DTIC Science & Technology

1991-05-23

rotational objects can b ec-tetd. E-Ac Ceedent 3exp-erimental demon ct r-ati ons for these tuo zethodsc hare L-en nerfor-med.A aner atohi naturve xs...dependent nature ---f the Joint rransifore f.Iter. Unlike theVa.dr %g~ii ssignal indepndent. a0. eir -las 3advata in real-tim ’-n14-a-entatio-n...a-tit reI ra-’ t --er is n -) 0 s-’ow Uha thsthoesc~-heo 8 spectral content of the target. A paper of this nature is published in the Optics and

Meta-Ethnography of Qualitative Research on the Experience of Being a Partner to an Individual with Schizophrenia Spectrum Disorder.

PubMed

Lewis, Laura Foran

2017-03-01

Several qualitative studies explore the experience of being a partner to an individual with schizophrenia spectrum disorder, but these studies remain isolated "islands of knowledge." This meta-ethnography aimed to synthesize current qualitative studies using Noblit and Hare's method. Thirteen studies were identified for inclusion. Three overarching themes were revealed: unmet expectations of relationship, renegotiating relationship roles, and separation versus togetherness. Themes interacted as a cycle with separation versus togetherness as temporal endpoints. Partners also renegotiated relationships with mental health professionals to accommodate unmet expectations. Leverage points for intervention were identified.

First evidence of established populations of the taiga tick Ixodes persulcatus (Acari: Ixodidae) in Sweden.

PubMed

Jaenson, Thomas G T; Värv, Kairi; Fröjdman, Isabella; Jääskeläinen, Anu; Rundgren, Kaj; Versteirt, Veerle; Estrada-Peña, Agustín; Medlock, Jolyon M; Golovljova, Irina

2016-07-01

The tick species Ixodes ricinus and I. persulcatus are of exceptional medical importance in the western and eastern parts, respectively, of the Palaearctic region. In Russia and Finland the range of I. persulcatus has recently increased. In Finland the first records of I. persulcatus are from 2004. The apparent expansion of its range in Finland prompted us to investigate if I. persulcatus also occurs in Sweden. Dog owners and hunters in the coastal areas of northern Sweden provided information about localities where ticks could be present. In May-August 2015 we used the cloth-dragging method in 36 localities potentially harbouring ticks in the Bothnian Bay area, province Norrbotten (NB) of northern Sweden. Further to the south in the provinces Västerbotten (VB) and Uppland (UP) eight localities were similarly investigated. Ixodes persulcatus was detected in 9 of 36 field localities in the Bothnian Bay area. Nymphs, adult males and adult females (n = 46 ticks) of I. persulcatus were present mainly in Alnus incana - Sorbus aucuparia - Picea abies - Pinus sylvestris vegetation communities on islands in the Bothnian Bay. Some of these I. persulcatus populations seem to be the most northerly populations so far recorded of this species. Dog owners asserted that their dogs became tick-infested on these islands for the first time 7-8 years ago. Moose (Alces alces), hares (Lepus timidus), domestic dogs (Canis lupus familiaris) and ground-feeding birds are the most likely carriers dispersing I. persulcatus in this area. All ticks (n = 124) from the more southern provinces of VB and UP were identified as I. ricinus. The geographical range of the taiga tick has recently expanded into northern Sweden. Increased information about prophylactic, anti-tick measures should be directed to people living in or visiting the coastal areas and islands of the Baltic Bay.

Canada lynx Lynx canadensis habitat and forest succession in northern Maine, USA

USGS Publications Warehouse

Hoving, C.L.; Harrison, D.J.; Krohn, W.B.; Jakubas, W.J.; McCollough, M.A.

2004-01-01

The contiguous United States population of Canada lynx Lynx canadensis was listed as threatened in 2000. The long-term viability of lynx populations at the southern edge of their geographic range has been hypothesized to be dependent on old growth forests; however, lynx are a specialist predator on snowshoe hare Lepus americanus, a species associated with early-successional forests. To quantify the effects of succession and forest management on landscape-scale (100 km2) patterns of habitat occupancy by lynx, we compared landscape attributes in northern Maine, USA, where lynx had been detected on snow track surveys to landscape attributes where surveys had been conducted, but lynx tracks had not been detected. Models were constructed a priori and compared using logistic regression and Akaike's Information Criterion (AIC), which quantitatively balances data fit and parsimony. In the models with the lowest (i.e. best) AIC, lynx were more likely to occur in landscapes with much regenerating forest, and less likely to occur in landscapes with much recent clearcut, partial harvest and forested wetland. Lynx were not associated positively or negatively with mature coniferous forest. A probabilistic map of the model indicated a patchy distribution of lynx habitat in northern Maine. According to an additional survey of the study area for lynx tracks during the winter of 2003, the model correctly classified 63.5% of the lynx occurrences and absences. Lynx were more closely associated with young forests than mature forests; however, old-growth forests were functionally absent from the landscape. Lynx habitat could be reduced in northern Maine, given recent trends in forest management practices. Harvest strategies have shifted from clearcutting to partial harvesting. If this trend continues, future landscapes will shift away from extensive regenerating forests and toward landscapes dominated by pole-sized and larger stands. Because Maine presently supports the only verified populations of this federally threatened species in the eastern United States, changes in forest management practices could affect recovery efforts throughout that region.

Evolutionary dynamics with fluctuating population sizes and strong mutualism.

PubMed

Chotibut, Thiparat; Nelson, David R

2015-08-01

Game theory ideas provide a useful framework for studying evolutionary dynamics in a well-mixed environment. This approach, however, typically enforces a strictly fixed overall population size, deemphasizing natural growth processes. We study a competitive Lotka-Volterra model, with number fluctuations, that accounts for natural population growth and encompasses interaction scenarios typical of evolutionary games. We show that, in an appropriate limit, the model describes standard evolutionary games with both genetic drift and overall population size fluctuations. However, there are also regimes where a varying population size can strongly influence the evolutionary dynamics. We focus on the strong mutualism scenario and demonstrate that standard evolutionary game theory fails to describe our simulation results. We then analytically and numerically determine fixation probabilities as well as mean fixation times using matched asymptotic expansions, taking into account the population size degree of freedom. These results elucidate the interplay between population dynamics and evolutionary dynamics in well-mixed systems.

Evolutionary dynamics with fluctuating population sizes and strong mutualism

NASA Astrophysics Data System (ADS)

Chotibut, Thiparat; Nelson, David R.

2015-08-01

Game theory ideas provide a useful framework for studying evolutionary dynamics in a well-mixed environment. This approach, however, typically enforces a strictly fixed overall population size, deemphasizing natural growth processes. We study a competitive Lotka-Volterra model, with number fluctuations, that accounts for natural population growth and encompasses interaction scenarios typical of evolutionary games. We show that, in an appropriate limit, the model describes standard evolutionary games with both genetic drift and overall population size fluctuations. However, there are also regimes where a varying population size can strongly influence the evolutionary dynamics. We focus on the strong mutualism scenario and demonstrate that standard evolutionary game theory fails to describe our simulation results. We then analytically and numerically determine fixation probabilities as well as mean fixation times using matched asymptotic expansions, taking into account the population size degree of freedom. These results elucidate the interplay between population dynamics and evolutionary dynamics in well-mixed systems.

Preface of the "Symposium on Mathematical Models and Methods to investigate Heterogeneity in Cell and Cell Population Biology"

NASA Astrophysics Data System (ADS)

Clairambault, Jean

2016-06-01

This session investigates hot topics related to mathematical representations of cell and cell population dynamics in biology and medicine, in particular, but not only, with applications to cancer. Methods in mathematical modelling and analysis, and in statistical inference using single-cell and cell population data, should contribute to focus this session on heterogeneity in cell populations. Among other methods are proposed: a) Intracellular protein dynamics and gene regulatory networks using ordinary/partial/delay differential equations (ODEs, PDEs, DDEs); b) Representation of cell population dynamics using agent-based models (ABMs) and/or PDEs; c) Hybrid models and multiscale models to integrate single-cell dynamics into cell population behaviour; d) Structured cell population dynamics and asymptotic evolution w.r.t. relevant traits; e) Heterogeneity in cancer cell populations: origin, evolution, phylogeny and methods of reconstruction; f) Drug resistance as an evolutionary phenotype: predicting and overcoming it in therapeutics; g) Theoretical therapeutic optimisation of combined drug treatments in cancer cell populations and in populations of other organisms, such as bacteria.

Predicting population dynamics from the properties of individuals: a cross-level test of dynamic energy budget theory.

PubMed

Martin, Benjamin T; Jager, Tjalling; Nisbet, Roger M; Preuss, Thomas G; Grimm, Volker

2013-04-01

Individual-based models (IBMs) are increasingly used to link the dynamics of individuals to higher levels of biological organization. Still, many IBMs are data hungry, species specific, and time-consuming to develop and analyze. Many of these issues would be resolved by using general theories of individual dynamics as the basis for IBMs. While such theories have frequently been examined at the individual level, few cross-level tests exist that also try to predict population dynamics. Here we performed a cross-level test of dynamic energy budget (DEB) theory by parameterizing an individual-based model using individual-level data of the water flea, Daphnia magna, and comparing the emerging population dynamics to independent data from population experiments. We found that DEB theory successfully predicted population growth rates and peak densities but failed to capture the decline phase. Further assumptions on food-dependent mortality of juveniles were needed to capture the population dynamics after the initial population peak. The resulting model then predicted, without further calibration, characteristic switches between small- and large-amplitude cycles, which have been observed for Daphnia. We conclude that cross-level tests help detect gaps in current individual-level theories and ultimately will lead to theory development and the establishment of a generic basis for individual-based models and ecology.

Population dynamics of Aphis gossypii Glover and in sole and intercropping systems of cotton and cowpea.

PubMed

Fernandes, Francisco S; Godoy, Wesley A C; Ramalho, Francisco S; Garcia, Adriano G; Santos, Bárbara D B; Malaquias, José B

2018-01-01

Population dynamics of aphids have been studied in sole and intercropping systems. These studies have required the use of more precise analytical tools in order to better understand patterns in quantitative data. Mathematical models are among the most important tools to explain the dynamics of insect populations. This study investigated the population dynamics of aphids Aphis gossypii and Aphis craccivora over time, using mathematical models composed of a set of differential equations as a helpful analytical tool to understand the population dynamics of aphids in arrangements of cotton and cowpea. The treatments were sole cotton, sole cowpea, and three arrangements of cotton intercropped with cowpea (t1, t2 and t3). The plants were infested with two aphid species and were evaluated at 7, 14, 28, 35, 42, and 49 days after the infestations. Mathematical models were used to fit the population dynamics of two aphid species. There were good fits for aphid dynamics by mathematical model over time. The highest population peak of both species A. gossypii and A. craccivora was found in the sole crops, and the lowest population peak was found in crop system t2. These results are important for integrated management programs of aphids in cotton and cowpea.

Comparing models of Red Knot population dynamics

USGS Publications Warehouse

McGowan, Conor P.

2015-01-01

Predictive population modeling contributes to our basic scientific understanding of population dynamics, but can also inform management decisions by evaluating alternative actions in virtual environments. Quantitative models mathematically reflect scientific hypotheses about how a system functions. In Delaware Bay, mid-Atlantic Coast, USA, to more effectively manage horseshoe crab (Limulus polyphemus) harvests and protect Red Knot (Calidris canutus rufa) populations, models are used to compare harvest actions and predict the impacts on crab and knot populations. Management has been chiefly driven by the core hypothesis that horseshoe crab egg abundance governs the survival and reproduction of migrating Red Knots that stopover in the Bay during spring migration. However, recently, hypotheses proposing that knot dynamics are governed by cyclical lemming dynamics garnered some support in data analyses. In this paper, I present alternative models of Red Knot population dynamics to reflect alternative hypotheses. Using 2 models with different lemming population cycle lengths and 2 models with different horseshoe crab effects, I project the knot population into the future under environmental stochasticity and parametric uncertainty with each model. I then compare each model's predictions to 10 yr of population monitoring from Delaware Bay. Using Bayes' theorem and model weight updating, models can accrue weight or support for one or another hypothesis of population dynamics. With 4 models of Red Knot population dynamics and only 10 yr of data, no hypothesis clearly predicted population count data better than another. The collapsed lemming cycle model performed best, accruing ~35% of the model weight, followed closely by the horseshoe crab egg abundance model, which accrued ~30% of the weight. The models that predicted no decline or stable populations (i.e. the 4-yr lemming cycle model and the weak horseshoe crab effect model) were the most weakly supported.

Considering transient population dynamics in the conservation of slow life-history species: An application to the sandhill crane

USGS Publications Warehouse

Gerber, Brian D.; Kendall, William L.

2016-01-01

The importance of transient dynamics of structured populations is increasingly recognized in ecology, yet these implications are not largely considered in conservation practices. We investigate transient and long-term population dynamics to demonstrate the process and utility of incorporating transient dynamics into conservation research and to better understand the population management of slow life-history species; these species can be theoretically highly sensitive to short- and long-term transient effects. We are specifically interested in the effects of anthropogenic removal of individuals from populations, such as caused by harvest, poaching, translocation, or incidental take. We use the sandhill crane (Grus canadensis) as an exemplar species; it is long-lived, has low reproduction, late maturity, and multiple populations are subject to sport harvest. We found sandhill cranes to have extremely high potential, but low likelihood for transient dynamics, even when the population is being harvested. The typically low population growth rate of slow life-history species appears to buffer against many perturbations causing large transient effects. Transient dynamics will dominate population trajectories of these species when stage structures are highly biased towards the younger and non-reproducing individuals, a situation that may be rare in established populations of long-lived animals. However, short-term transient population growth can be highly sensitive to vital rates that are relatively insensitive under equilibrium, suggesting that stage structure should be known if perturbation analysis is used to identify effective conservation strategies. For populations of slow life-history species that are not prone to large perturbations to their most productive individuals, population growth may be approximated by equilibrium dynamics.

How Ebola impacts social dynamics in gorillas: a multistate modelling approach.

PubMed

Genton, Céline; Pierre, Amandine; Cristescu, Romane; Lévréro, Florence; Gatti, Sylvain; Pierre, Jean-Sébastien; Ménard, Nelly; Le Gouar, Pascaline

2015-01-01

Emerging infectious diseases can induce rapid changes in population dynamics and threaten population persistence. In socially structured populations, the transfers of individuals between social units, for example, from breeding groups to non-breeding groups, shape population dynamics. We suggest that diseases may affect these crucial transfers. We aimed to determine how disturbance by an emerging disease affects demographic rates of gorillas, especially transfer rates within populations and immigration rates into populations. We compared social dynamics and key demographic parameters in a gorilla population affected by Ebola using a long-term observation data set including pre-, during and post-outbreak periods. We also studied a population of undetermined epidemiological status in order to assess whether this population was affected by the disease. We developed a multistate model that can handle transition between social units while optimizing the number of states. During the Ebola outbreak, social dynamics displayed increased transfers from a breeding to a non-breeding status for both males and females. Six years after the outbreak, demographic and most of social dynamics parameters had returned to their initial rates, suggesting a certain resilience in the response to disruption. The formation of breeding groups increased just after Ebola, indicating that environmental conditions were still attractive. However, population recovery was likely delayed because compensatory immigration was probably impeded by the potential impact of Ebola in the surrounding areas. The population of undetermined epidemiological status behaved similarly to the other population before Ebola. Our results highlight the need to integrate social dynamics in host-population demographic models to better understand the role of social structure in the sensitivity and the response to disease disturbances. © 2014 The Authors. Journal of Animal Ecology © 2014 British Ecological Society.

Cadmium, lead, and mercury exposure assessment among croatian consumers of free-living game.

PubMed

Lazarus, Maja; Prevendar Crnić, Andreja; Bilandžić, Nina; Kusak, Josip; Reljić, Slaven

2014-09-29

Free-living game can be an important source of dietary cadmium and lead; the question is whether exposure to these two elements is such that it might cause adverse health effects in the consumers. The aim of this study was to estimate dietary exposure to cadmium, lead, and mercury from free-living big game (fallow deer, roe deer, red deer, wild boar, and brown bear), and to mercury from small game (pheasant and hare), hunted in Croatia from 1990 to 2012. The exposure assessment was based on available literature data and our own measurements of metal levels in the tissues of the game, by taking into account different consumption frequencies (four times a year, once a month and once a week). Exposure was expressed as percentage of (provisional) tolerable weekly intake [(P)TWI] values set by the European Food Safety Authority (EFSA). Consumption of game meat (0.002-0.5 % PTWI) and liver (0.005-6 % PTWI) assumed for the general population (four times a year) does not pose a health risk to consumers from the general population, nor does monthly (0.02-6 % PTWI) and weekly (0.1-24 % PTWI) consumption of game meat. However, because of the high percentage of free-living game liver and kidney samples exceeding the legislative limits for cadmium (2-99 %) and lead (1-82 %), people should keep the consumption of certain game species' offal as low as possible. Children and pregnant and lactating women should avoid eating game offal altogether. Free-living game liver could be an important source of cadmium if consumed on a monthly basis (3-74 % TWI), and if consumed weekly (11-297 % TWI), it could even give rise to toxicological concern.

Wild game consumption habits among Italian shooters: relevance for intakes of cadmium, perfluorooctanesulphonic acid, and 137cesium as priority contaminants.

PubMed

Ferri, Mauro; Baldi, Loredana; Cavallo, Stefania; Pellicanò, Roberta; Brambilla, Gianfranco

2017-05-01

The consumption habits of 766 Italian shooters (96% males, 4% females), on average 52 years old, have been investigated, in Italy, through the distribution of questionnaires delivered during shooters' attendance to training and teaching courses, in compliance with 853/2004/EC Regulation provisions on food hygiene. The most consumed wild species recorded were pheasant > woodcock > choke among feathered animals, and wild boar > hare > roe deer among mammals, respectively. An average of 100-200 g game per serving (four servings per month) was consumed, with highest intakes of 3000 g per month; meat, liver, and heart were the preferred food items. Mammalian and feathered game was regularly consumed with friends and relatives in 83% and in 60% of cases, respectively. Accounting for an inventoried population of 751,876 shooters in Italy, it is estimated that there is regular consumption of wild game in around the 3% of the Italian population. More than 80% of responders were aware of health risks related to game handling and to food safety issues. Due to the occurrence in wild boar meat and liver of the heavy metal cadmium (Cd), the persistent organic pollutant perfluorooctan sulphonic acid (PFOS), and the radionuclide 137 cesium ( 137 Cs), it was possible to demonstrate the usefulness of such a food consumption database for intake assessment in this sensitive group of consumers. In high consumers of wild boar, threshold concentrations for intakes have been estimated in the ranges of 48-93 ng g -1 for Cd, 35-67 ng g -1 for PFOS and 0.20-0.34 Bq kg -1 for 137 Cs.

Stochastic gain in finite populations

NASA Astrophysics Data System (ADS)

Röhl, Torsten; Traulsen, Arne; Claussen, Jens Christian; Schuster, Heinz Georg

2008-08-01

Flexible learning rates can lead to increased payoffs under the influence of noise. In a previous paper [Traulsen , Phys. Rev. Lett. 93, 028701 (2004)], we have demonstrated this effect based on a replicator dynamics model which is subject to external noise. Here, we utilize recent advances on finite population dynamics and their connection to the replicator equation to extend our findings and demonstrate the stochastic gain effect in finite population systems. Finite population dynamics is inherently stochastic, depending on the population size and the intensity of selection, which measures the balance between the deterministic and the stochastic parts of the dynamics. This internal noise can be exploited by a population using an appropriate microscopic update process, even if learning rates are constant.

How Does a Divided Population Respond to Change?

PubMed

Qubbaj, Murad R; Muneepeerakul, Rachata; Aggarwal, Rimjhim M; Anderies, John M

2015-01-01

Most studies on the response of socioeconomic systems to a sudden shift focus on long-term equilibria or end points. Such narrow focus forgoes many valuable insights. Here we examine the transient dynamics of regime shift on a divided population, exemplified by societies divided ideologically, politically, economically, or technologically. Replicator dynamics is used to investigate the complex transient dynamics of the population response. Though simple, our modeling approach exhibits a surprisingly rich and diverse array of dynamics. Our results highlight the critical roles played by diversity in strategies and the magnitude of the shift. Importantly, it allows for a variety of strategies to arise organically as an integral part of the transient dynamics--as opposed to an independent process--of population response to a regime shift, providing a link between the population's past and future diversity patterns. Several combinations of different populations' strategy distributions and shifts were systematically investigated. Such rich dynamics highlight the challenges of anticipating the response of a divided population to a change. The findings in this paper can potentially improve our understanding of a wide range of socio-ecological and technological transitions.

Coordinated dynamic encoding in the retina using opposing forms of plasticity

PubMed Central

Kastner, David B.; Baccus, Stephen A.

2011-01-01

The range of natural inputs encoded by a neuron often exceeds its dynamic range. To overcome this limitation, neural populations divide their inputs among different cell classes, as with rod and cone photoreceptors, and adapt by shifting their dynamic range. We report that the dynamic behavior of retinal ganglion cells in salamanders, mice, and rabbits is divided into two opposing forms of short-term plasticity in different cell classes. One population of cells exhibited sensitization—a persistent elevated sensitivity following a strong stimulus. This novel dynamic behavior compensates for the information loss caused by the known process of adaptation occurring in a separate cell population. The two populations divide the dynamic range of inputs, with sensitizing cells encoding weak signals, and adapting cells encoding strong signals. In the two populations, the linear, threshold and adaptive properties are linked to preserve responsiveness when stimulus statistics change, with one population maintaining the ability to respond when the other fails. PMID:21909086

Population variation and individual maximum size in two leech populations: energy extraction from cannibalism or niche widening?

PubMed

Persson, Lennart; Elliott, J Malcolm

2013-05-01

The theory of cannibal dynamics predicts a link between population dynamics and individual life history. In particular, increased individual growth has, in both modeling and empirical studies, been shown to result from a destabilization of population dynamics. We used data from a long-term study of the dynamics of two leech (Erpobdella octoculata) populations to test the hypothesis that maximum size should be higher in a cycling population; one of the study populations exhibited a delayed feedback cycle while the other population showed no sign of cyclicity. A hump-shaped relationship between individual mass of 1-year-old leeches and offspring density the previous year was present in both populations. As predicted from the theory, the maximum mass of individuals was much larger in the fluctuating population. In contrast to predictions, the higher growth rate was not related to energy extraction from cannibalism. Instead, the higher individual mass is suggested to be due to increased availability of resources due to a niche widening with increased individual body mass. The larger individual mass in the fluctuating population was related to a stronger correlation between the densities of 1-year-old individuals and 2-year-old individuals the following year in this population. Although cannibalism was the major mechanism regulating population dynamics, its importance was negligible in terms of providing cannibalizing individuals with energy subsequently increasing their fecundity. Instead, the study identifies a need for theoretical and empirical studies on the largely unstudied interplay between ontogenetic niche shifts and cannibalistic population dynamics.

The finite state projection approach to analyze dynamics of heterogeneous populations

NASA Astrophysics Data System (ADS)

Johnson, Rob; Munsky, Brian

2017-06-01

Population modeling aims to capture and predict the dynamics of cell populations in constant or fluctuating environments. At the elementary level, population growth proceeds through sequential divisions of individual cells. Due to stochastic effects, populations of cells are inherently heterogeneous in phenotype, and some phenotypic variables have an effect on division or survival rates, as can be seen in partial drug resistance. Therefore, when modeling population dynamics where the control of growth and division is phenotype dependent, the corresponding model must take account of the underlying cellular heterogeneity. The finite state projection (FSP) approach has often been used to analyze the statistics of independent cells. Here, we extend the FSP analysis to explore the coupling of cell dynamics and biomolecule dynamics within a population. This extension allows a general framework with which to model the state occupations of a heterogeneous, isogenic population of dividing and expiring cells. The method is demonstrated with a simple model of cell-cycle progression, which we use to explore possible dynamics of drug resistance phenotypes in dividing cells. We use this method to show how stochastic single-cell behaviors affect population level efficacy of drug treatments, and we illustrate how slight modifications to treatment regimens may have dramatic effects on drug efficacy.

Extreme D'Hondt and round-off effects in voting computations

NASA Astrophysics Data System (ADS)

Konstantinov, M. M.; Pelova, G. B.

2015-11-01

D'Hondt (or Jefferson) method and Hare-Niemeyer (or Hamilton) method are widely used worldwide for seat allocation in proportional systems. Everything seems to be well known in this area. However, this is not the case. For example the D'Hondt method can violate the quota rule from above but this effect is not analyzed as a function of the number of parties and/or the threshold used. Also, allocation methods are often implemented automatically as computer codes in machine arithmetic believing that following the IEEE standards for double precision binary arithmetics would guarantee correct results. Unfortunately this may not happen not only for double precision arithmetic (usually producing 15-16 true decimal digits) but also for any relative precision of the underlying binary machine arithmetics. This paper deals with the following new issues.Find conditions (threshold in particular) such that D'Hondt seat allocation violates maximally the quota rule. Analyze possible influence of rounding errors in the automatic implementation of Hare-Niemeyer method in machine arithmetic.Concerning the first issue, it is known that the maximal deviation of D'Hondt allocation from upper quota for the Bulgarian proportional system (240 MP and 4% barrier) is 5. This fact had been established in 1991. A classical treatment of voting issues is the monograph [1], while electoral problems specific for Bulgaria have been treated in [2, 4]. The effect of threshold on extreme seat allocations is also analyzed in [3]. Finally we would like to stress that Voting Theory may sometimes be mathematically trivial but always has great political impact. This is a strong motivation for further investigations in this area.

Do terrestrial animals avoid areas close to turbines in functioning wind farms in agricultural landscapes?

PubMed

Łopucki, Rafał; Klich, Daniel; Gielarek, Sylwia

2017-07-01

Most studies on the effects of wind energy on animals have focused on avian and bat activity, habitat use, and mortality, whereas very few have been published on terrestrial, non-volant wildlife. In this paper, we studied the utilization of functioning wind farm areas by four terrestrial animals common to agricultural landscapes: European roe deer, European hare, red fox, and the common pheasant. Firstly, we expected that the studied animals do not avoid areas close to turbines and utilize the whole area of functioning wind farms with a frequency similar to the control areas. Secondly, we expected that there is no relation between the turbine proximity and the number of tracks of these animals. The study was conducted over two winter seasons using the snow-tracking method along 100 m linear transects. In total, 583 transects were recorded. Wind farm operations may affect terrestrial animals both in wind farm interiors and in a 700-m buffer zone around the edge of turbines. The reactions of animals were species specific. Herbivorous mammals (roe deer and European hare) avoided wind farm interiors and proximity to turbines. The common pheasant showed a positive reaction to wind turbine proximity. The red fox had the most neutral response to wind turbines. Although this species visited wind farm interiors less often than the control area, there was no relation between fox track density and turbine proximity. Greater weight should be given to the effects of wind farms on non-flying wildlife than at present. Investors and regulatory authorities should always consider the likely impacts of wind farms during environmental impact assessments and try to reduce these negative effects.

Abortion: a reader's guide.

PubMed

Hisel, L M

1996-01-01

This review traces the discussion of abortion in the US through 10 of the best books published on the subject in the past 25 years. The first book considered is Daniel Callahan's "Abortion: Law, Choice and Morality," which was published in 1970. Next is book of essays also published in 1970: "The Morality of Abortion: Legal and Historical Perspectives," which was edited by John T. Noonan, Jr., who became a prominent opponent to the Roe decision. It is noted that Roman Catholics would find the essay by Bernard Haring especially interesting since Haring supported the Church's position on abortion but called for acceptance of contraception. Third on the list is historian James C. Mohr's review of "Abortion in America: The Origins and Evolution of National Policy," which was printed five years after the Roe decision. Selection four is "Enemies of Choice: The Right-to-Life Movement and Its Threat to Abortion" by Andrew Merton. This 1981 publication singled out a concern about sexuality as the overriding motivator for anti-abortion groups. Two years later, Beverly Wildung Harrison published a ground-breaking, feminist, moral analysis of abortion entitled "Our Right to Choose: Toward a New Ethic of Abortion. This was followed by a more empirical and sociopolitical feminist analysis in Kristin Luker's 1984 "Abortion and the Politics of Motherhood." The seventh book is by another feminist, Rosalind Pollack Petchesky, whose work "Abortion and Women's Choice: The State, Sexuality, and Reproductive Freedom" was first published in 1984 and reprinted in 1990. The eighth important book was "Abortion and Catholicism: The American Debate," edited by Thomas A. Shannon and Patricia Beattie Jung. Rounding out the list are the 1992 work "Life Itself: Abortion in the American Mind" by Roger Rosenblatt and Ronald Dworkin's 1993 "Life's Dominion: An Argument About Abortion, Euthanasia, and Individual Freedom."

Use of Mobile Device Data To Better Estimate Dynamic Population Size for Wastewater-Based Epidemiology.

PubMed

Thomas, Kevin V; Amador, Arturo; Baz-Lomba, Jose Antonio; Reid, Malcolm

2017-10-03

Wastewater-based epidemiology is an established approach for quantifying community drug use and has recently been applied to estimate population exposure to contaminants such as pesticides and phthalate plasticizers. A major source of uncertainty in the population weighted biomarker loads generated is related to estimating the number of people present in a sewer catchment at the time of sample collection. Here, the population quantified from mobile device-based population activity patterns was used to provide dynamic population normalized loads of illicit drugs and pharmaceuticals during a known period of high net fluctuation in the catchment population. Mobile device-based population activity patterns have for the first time quantified the high degree of intraday, week, and month variability within a specific sewer catchment. Dynamic population normalization showed that per capita pharmaceutical use remained unchanged during the period when static normalization would have indicated an average reduction of up to 31%. Per capita illicit drug use increased significantly during the monitoring period, an observation that was only possible to measure using dynamic population normalization. The study quantitatively confirms previous assessments that population estimates can account for uncertainties of up to 55% in static normalized data. Mobile device-based population activity patterns allow for dynamic normalization that yields much improved temporal and spatial trend analysis.

Eco-evolutionary dynamics in a coevolving host-virus system.

PubMed

Frickel, Jens; Sieber, Michael; Becks, Lutz

2016-04-01

Eco-evolutionary dynamics have been shown to be important for understanding population and community stability and their adaptive potential. However, coevolution in the framework of eco-evolutionary theory has not been addressed directly. Combining experiments with an algal host and its viral parasite, and mathematical model analyses we show eco-evolutionary dynamics in antagonistic coevolving populations. The interaction between antagonists initially resulted in arms race dynamics (ARD) with selective sweeps, causing oscillating host-virus population dynamics. However, ARD ended and populations stabilised after the evolution of a general resistant host, whereas a trade-off between host resistance and growth then maintained host diversity over time (trade-off driven dynamics). Most importantly, our study shows that the interaction between ecology and evolution had important consequences for the predictability of the mode and tempo of adaptive change and for the stability and adaptive potential of populations. © 2016 John Wiley & Sons Ltd/CNRS.

Evolution of specialization under non-equilibrium population dynamics.

PubMed

Nurmi, Tuomas; Parvinen, Kalle

2013-03-21

We analyze the evolution of specialization in resource utilization in a mechanistically underpinned discrete-time model using the adaptive dynamics approach. We assume two nutritionally equivalent resources that in the absence of consumers grow sigmoidally towards a resource-specific carrying capacity. The consumers use resources according to the law of mass-action with rates involving trade-off. The resulting discrete-time model for the consumer population has over-compensatory dynamics. We illuminate the way non-equilibrium population dynamics affect the evolutionary dynamics of the resource consumption rates, and show that evolution to the trimorphic coexistence of a generalist and two specialists is possible due to asynchronous non-equilibrium population dynamics of the specialists. In addition, various forms of cyclic evolutionary dynamics are possible. Furthermore, evolutionary suicide may occur even without Allee effects and demographic stochasticity. Copyright © 2013 Elsevier Ltd. All rights reserved.

A framework for studying transient dynamics of population projection matrix models.

PubMed

Stott, Iain; Townley, Stuart; Hodgson, David James

2011-09-01

Empirical models are central to effective conservation and population management, and should be predictive of real-world dynamics. Available modelling methods are diverse, but analysis usually focuses on long-term dynamics that are unable to describe the complicated short-term time series that can arise even from simple models following ecological disturbances or perturbations. Recent interest in such transient dynamics has led to diverse methodologies for their quantification in density-independent, time-invariant population projection matrix (PPM) models, but the fragmented nature of this literature has stifled the widespread analysis of transients. We review the literature on transient analyses of linear PPM models and synthesise a coherent framework. We promote the use of standardised indices, and categorise indices according to their focus on either convergence times or transient population density, and on either transient bounds or case-specific transient dynamics. We use a large database of empirical PPM models to explore relationships between indices of transient dynamics. This analysis promotes the use of population inertia as a simple, versatile and informative predictor of transient population density, but criticises the utility of established indices of convergence times. Our findings should guide further development of analyses of transient population dynamics using PPMs or other empirical modelling techniques. © 2011 Blackwell Publishing Ltd/CNRS.

Dispersal, density dependence, and population dynamics of a fungal microbe on leaf surfaces.

PubMed

Woody, Scott T; Ives, Anthony R; Nordheim, Erik V; Andrews, John H

2007-06-01

Despite the ubiquity and importance of microbes in nature, little is known about their natural population dynamics, especially for those that occupy terrestrial habitats. Here we investigate the dynamics of the yeast-like fungus Aureobasidium pullulans (Ap) on apple leaves in an orchard. We asked three questions. (1) Is variation in fungal population density among leaves caused by variation in leaf carrying capacities and strong density-dependent population growth that maintains densities near carrying capacity? (2) Do resident populations have competitive advantages over immigrant cells? (3) Do Ap dynamics differ at different times during the growing season? To address these questions, we performed two experiments at different times in the growing season. Both experiments used a 2 x 2 factorial design: treatment 1 removed fungal cells from leaves to reveal density-dependent population growth, and treatment 2 inoculated leaves with an Ap strain engineered to express green fluorescent protein (GFP), which made it possible to track the fate of immigrant cells. The experiments showed that natural populations of Ap vary greatly in density due to sustained differences in carrying capacities among leaves. The maintenance of populations close to carrying capacities indicates strong density-dependent processes. Furthermore, resident populations are strongly competitive against immigrants, while immigrants have little impact on residents. Finally, statistical models showed high population growth rates of resident cells in one experiment but not in the other, suggesting that Ap experiences relatively "good" and "bad" periods for population growth. This picture of Ap dynamics conforms to commonly held, but rarely demonstrated, expectations of microbe dynamics in nature. It also highlights the importance of local processes, as opposed to immigration, in determining the abundance and dynamics of microbes on surfaces in terrestrial systems.

Rapid evolution leads to differential population dynamics and top-down control in resurrected Daphnia populations.

PubMed

Goitom, Eyerusalem; Kilsdonk, Laurens J; Brans, Kristien; Jansen, Mieke; Lemmens, Pieter; De Meester, Luc

2018-01-01

There is growing evidence of rapid genetic adaptation of natural populations to environmental change, opening the perspective that evolutionary trait change may subsequently impact ecological processes such as population dynamics, community composition, and ecosystem functioning. To study such eco-evolutionary feedbacks in natural populations, however, requires samples across time. Here, we capitalize on a resurrection ecology study that documented rapid and adaptive evolution in a natural population of the water flea Daphnia magna in response to strong changes in predation pressure by fish, and carry out a follow-up mesocosm experiment to test whether the observed genetic changes influence population dynamics and top-down control of phytoplankton. We inoculated populations of the water flea D. magna derived from three time periods of the same natural population known to have genetically adapted to changes in predation pressure in replicate mesocosms and monitored both Daphnia population densities and phytoplankton biomass in the presence and absence of fish. Our results revealed differences in population dynamics and top-down control of algae between mesocosms harboring populations from the time period before, during, and after a peak in fish predation pressure caused by human fish stocking. The differences, however, deviated from our a priori expectations. An S-map approach on time series revealed that the interactions between adults and juveniles strongly impacted the dynamics of populations and their top-down control on algae in the mesocosms, and that the strength of these interactions was modulated by rapid evolution as it occurred in nature. Our study provides an example of an evolutionary response that fundamentally alters the processes structuring population dynamics and impacts ecosystem features.

Feedback between Population and Evolutionary Dynamics Determines the Fate of Social Microbial Populations

PubMed Central

Sanchez, Alvaro; Gore, Jeff

2013-01-01

The evolutionary spread of cheater strategies can destabilize populations engaging in social cooperative behaviors, thus demonstrating that evolutionary changes can have profound implications for population dynamics. At the same time, the relative fitness of cooperative traits often depends upon population density, thus leading to the potential for bi-directional coupling between population density and the evolution of a cooperative trait. Despite the potential importance of these eco-evolutionary feedback loops in social species, they have not yet been demonstrated experimentally and their ecological implications are poorly understood. Here, we demonstrate the presence of a strong feedback loop between population dynamics and the evolutionary dynamics of a social microbial gene, SUC2, in laboratory yeast populations whose cooperative growth is mediated by the SUC2 gene. We directly visualize eco-evolutionary trajectories of hundreds of populations over 50–100 generations, allowing us to characterize the phase space describing the interplay of evolution and ecology in this system. Small populations collapse despite continual evolution towards increased cooperative allele frequencies; large populations with a sufficient number of cooperators “spiral” to a stable state of coexistence between cooperator and cheater strategies. The presence of cheaters does not significantly affect the equilibrium population density, but it does reduce the resilience of the population as well as its ability to adapt to a rapidly deteriorating environment. Our results demonstrate the potential ecological importance of coupling between evolutionary dynamics and the population dynamics of cooperatively growing organisms, particularly in microbes. Our study suggests that this interaction may need to be considered in order to explain intraspecific variability in cooperative behaviors, and also that this feedback between evolution and ecology can critically affect the demographic fate of those species that rely on cooperation for their survival. PMID:23637571

Modelling the dynamics of traits involved in fighting-predators-prey system.

PubMed

Kooi, B W

2015-12-01

We study the dynamics of a predator-prey system where predators fight for captured prey besides searching for and handling (and digestion) of the prey. Fighting for prey is modelled by a continuous time hawk-dove game dynamics where the gain depends on the amount of disputed prey while the costs for fighting is constant per fighting event. The strategy of the predator-population is quantified by a trait being the proportion of the number of predator-individuals playing hawk tactics. The dynamics of the trait is described by two models of adaptation: the replicator dynamics (RD) and the adaptive dynamics (AD). In the RD-approach a variant individual with an adapted trait value changes the population's strategy, and consequently its trait value, only when its payoff is larger than the population average. In the AD-approach successful replacement of the resident population after invasion of a rare variant population with an adapted trait value is a step in a sequence changing the population's strategy, and hence its trait value. The main aim is to compare the consequences of the two adaptation models. In an equilibrium predator-prey system this will lead to convergence to a neutral singular strategy, while in the oscillatory system to a continuous singular strategy where in this endpoint the resident population is not invasible by any variant population. In equilibrium (low prey carrying capacity) RD and AD-approach give the same results, however not always in a periodically oscillating system (high prey carrying-capacity) where the trait is density-dependent. For low costs the predator population is monomorphic (only hawks) while for high costs dimorphic (hawks and doves). These results illustrate that intra-specific trait dynamics matters in predator-prey dynamics.

Effects of an invasive plant on population dynamics in toads.

PubMed

Greenberg, Daniel A; Green, David M

2013-10-01

When populations decline in response to unfavorable environmental change, the dynamics of their population growth shift. In populations that normally exhibit high levels of variation in recruitment and abundance, as do many amphibians, declines may be difficult to identify from natural fluctuations in abundance. However, the onset of declines may be evident from changes in population growth rate in sufficiently long time series of population data. With data from 23 years of study of a population of Fowler's toad (Anaxyrus [ = Bufo] fowleri) at Long Point, Ontario (1989-2011), we sought to identify such a shift in dynamics. We tested for trends in abundance to detect a change point in population dynamics and then tested among competing population models to identify associated intrinsic and extrinsic factors. The most informative models of population growth included terms for toad abundance and the extent of an invasive marsh plant, the common reed (Phragmites australis), throughout the toads' marshland breeding areas. Our results showed density-dependent growth in the toad population from 1989 through 2002. After 2002, however, we found progressive population decline in the toads associated with the spread of common reeds and consequent loss of toad breeding habitat. This resulted in reduced recruitment and population growth despite the lack of significant loss of adult habitat. Our results underscore the value of using long-term time series to identify shifts in population dynamics coincident with the advent of population decline. © 2013 Society for Conservation Biology.

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

ADVANCE [Advanced Driver and Vehicle Advisory Navigation ConcEpt] was a public/private partnership conceived and developed by four founding parties. The founding parties include the Federal Highway Administration (FHWA), the Illinois Department of Transportation (IDOT), the University of Illinois at Chicago and Northwestern University operating together under the auspices of the Illinois Universities Transportation Research Consortium (IUTRC), and Motorola, Inc. The major responsibilities of each party are fully described in the Project agreement. Subsequently, these four were joined on the Steering Committee by the American Automobile Association (AAA). This unique blending of public sector, private sector and university interests, augmented bymore » more than two dozen other private sector participants, provided a strong set of resources for ADVANCE. The ADVANCE test area covered over 300 square miles including portions of the City of Chicago and 40 northwest suburban communities. The Project encompasses the high growth areas adjacent to O`Hare International Airport, the Schaumburg/Hoffman Estates office and retail complexes, and the Lake-Cook Road development corridor. It also includes major sports and entertainment complexes such as the Arlington International Racecourse and the Rosemont Horizon. The population in the area is more than 750,000. The Insights and Perspectives Compendium is intended to provide useful information to project managers, system developers, and system integrators of future similar ITS implementations. It is intended for those that are technically interested in the ADVANCE Project and have a basic understanding of the project.« less

Temperature-driven regime shifts in the dynamics of size-structured populations.

PubMed

Ohlberger, Jan; Edeline, Eric; Vøllestad, Leif Asbjørn; Stenseth, Nils C; Claessen, David

2011-02-01

Global warming impacts virtually all biota and ecosystems. Many of these impacts are mediated through direct effects of temperature on individual vital rates. Yet how this translates from the individual to the population level is still poorly understood, hampering the assessment of global warming impacts on population structure and dynamics. Here, we study the effects of temperature on intraspecific competition and cannibalism and the population dynamical consequences in a size-structured fish population. We use a physiologically structured consumer-resource model in which we explicitly model the temperature dependencies of the consumer vital rates and the resource population growth rate. Our model predicts that increased temperature decreases resource density despite higher resource growth rates, reflecting stronger intraspecific competition among consumers. At a critical temperature, the consumer population dynamics destabilize and shift from a stable equilibrium to competition-driven generation cycles that are dominated by recruits. As a consequence, maximum age decreases and the proportion of younger and smaller-sized fish increases. These model predictions support the hypothesis of decreasing mean body sizes due to increased temperatures. We conclude that in size-structured fish populations, global warming may increase competition, favor smaller size classes, and induce regime shifts that destabilize population and community dynamics.

Transient synchrony among populations of five foliage-feeding Lepidoptera

Treesearch

Maartje J. Klapwijk; Jonathan A. Walter; Anikó Hirka; György Csóka; Christer Björkman; Andrew M. Liebhold

2018-01-01

Studies of transient population dynamics have largely focused on temporal changes in dynamical behaviour, such as the transition between periods of stability and instability. This study explores a related dynamic pattern, namely transient synchrony during a 49-year period among populations of five sympatric species of forest insects that share host tree resources. The...

Simple deterministic models and applications. Comment on "Coupled disease-behavior dynamics on complex networks: A review" by Z. Wang et al.

NASA Astrophysics Data System (ADS)

Yang, Hyun Mo

2015-12-01

Currently, discrete modellings are largely accepted due to the access to computers with huge storage capacity and high performance processors and easy implementation of algorithms, allowing to develop and simulate increasingly sophisticated models. Wang et al. [7] present a review of dynamics in complex networks, focusing on the interaction between disease dynamics and human behavioral and social dynamics. By doing an extensive review regarding to the human behavior responding to disease dynamics, the authors briefly describe the complex dynamics found in the literature: well-mixed populations networks, where spatial structure can be neglected, and other networks considering heterogeneity on spatially distributed populations. As controlling mechanisms are implemented, such as social distancing due 'social contagion', quarantine, non-pharmaceutical interventions and vaccination, adaptive behavior can occur in human population, which can be easily taken into account in the dynamics formulated by networked populations.

Measurements on Noise from Reflex Oscillators

DTIC Science & Technology

1945-12-21

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Integral projection models for finite populations in a stochastic environment.

PubMed

Vindenes, Yngvild; Engen, Steinar; Saether, Bernt-Erik

2011-05-01

Continuous types of population structure occur when continuous variables such as body size or habitat quality affect the vital parameters of individuals. These structures can give rise to complex population dynamics and interact with environmental conditions. Here we present a model for continuously structured populations with finite size, including both demographic and environmental stochasticity in the dynamics. Using recent methods developed for discrete age-structured models we derive the demographic and environmental variance of the population growth as functions of a continuous state variable. These two parameters, together with the expected population growth rate, are used to define a one-dimensional diffusion approximation of the population dynamics. Thus, a substantial reduction in complexity is achieved as the dynamics of the complex structured model can be described by only three population parameters. We provide methods for numerical calculation of the model parameters and demonstrate the accuracy of the diffusion approximation by computer simulation of specific examples. The general modeling framework makes it possible to analyze and predict future dynamics and extinction risk of populations with various types of structure, and to explore consequences of changes in demography caused by, e.g., climate change or different management decisions. Our results are especially relevant for small populations that are often of conservation concern.

How Does a Divided Population Respond to Change?

PubMed Central

Qubbaj, Murad R.; Muneepeerakul, Rachata; Aggarwal, Rimjhim M.; Anderies, John M.

2015-01-01

Most studies on the response of socioeconomic systems to a sudden shift focus on long-term equilibria or end points. Such narrow focus forgoes many valuable insights. Here we examine the transient dynamics of regime shift on a divided population, exemplified by societies divided ideologically, politically, economically, or technologically. Replicator dynamics is used to investigate the complex transient dynamics of the population response. Though simple, our modeling approach exhibits a surprisingly rich and diverse array of dynamics. Our results highlight the critical roles played by diversity in strategies and the magnitude of the shift. Importantly, it allows for a variety of strategies to arise organically as an integral part of the transient dynamics—as opposed to an independent process—of population response to a regime shift, providing a link between the population's past and future diversity patterns. Several combinations of different populations' strategy distributions and shifts were systematically investigated. Such rich dynamics highlight the challenges of anticipating the response of a divided population to a change. The findings in this paper can potentially improve our understanding of a wide range of socio-ecological and technological transitions. PMID:26161859

High population variability and source-sink dynamics in a solitary bee species.

PubMed

Franzén, Markus; Nilsson, Sven G

2013-06-01

Although solitary bees are considered to play key roles in ecosystem functions, surprisingly few studies have explored their population dynamics. We investigated the population dynamics of a rare, declining, solitary bee (Andrena humilis) in a landscape of 80 km2 in southern Sweden from 2003 to 2011. Only one population was persistent throughout all years studied; most likely this population supplied the surrounding landscape with 11 smaller, temporary local populations. Despite stable pollen availability, the size of the persistent population fluctuated dramatically in a two-year cycle over the nine years, with 490-1230 nests in odd-numbered years and 21-48 nests in even-numbered years. These fluctuations were not significantly related to climatic variables or pollen availability. Nineteen colonization and 14 extinction events were recorded. Occupancy decreased with distance from the persistent population and increased with increasing resource (pollen) availability. There were significant positive correlations between the size of the persistent population and patch occupancy and colonization. Colonizations were generally more common in patches closer to the persistent population, whereas extinctions were independent of distance from the persistent population. Our results highlight the complex population dynamics that exist for this solitary bee species, which could be due to source-sink dynamics, a prolonged diapause, or can represent a bet-hedging strategy to avoid natural enemies and survive in small habitat patches. If large fluctuations in solitary bee populations prove to be widespread, it will have important implications for interpreting ecological relationships, bee conservation, and pollination.

Density dependence in group dynamics of a highly social mongoose, Suricata suricatta.

PubMed

Bateman, Andrew W; Ozgul, Arpat; Coulson, Tim; Clutton-Brock, Tim H

2012-05-01

1. For social species, the link between individual behaviour and population dynamics is mediated by group-level demography. 2. Populations of obligate cooperative breeders are structured into social groups, which may be subject to inverse density dependence (Allee effects) that result from a dependence on conspecific helpers, but evidence for population-wide Allee effects is rare. 3. We use field data from a long-term study of cooperative meerkats (Suricata suricatta; Schreber, 1776) - a species for which local Allee effects are not reflected in population-level dynamics - to empirically model interannual group dynamics. 4. Using phenomenological population models, modified to incorporate environmental conditions and potential Allee effects, we first investigate overall patterns of group dynamics and find support only for conventional density dependence that increases after years of low rainfall. 5. To explain the observed patterns, we examine specific demographic rates and assess their contributions to overall group dynamics. Although per-capita meerkat mortality is subject to a component Allee effect, it contributes relatively little to observed variation in group dynamics, and other (conventionally density dependent) demographic rates - especially emigration - govern group dynamics. 6. Our findings highlight the need to consider demographic processes and density dependence in subpopulations before drawing conclusions about how behaviour affects population processes in socially complex systems. © 2011 The Authors. Journal of Animal Ecology © 2011 British Ecological Society.

Comparative phylogeny and historical perspectives on population genetics of the Pacific hawksbill (Eretmochelys imbricata) and green turtles (Chelonia mydas), inferred from feeding populations in the Yaeyama Islands, Japan.

PubMed

Nishizawa, Hideaki; Okuyama, Junichi; Kobayashi, Masato; Abe, Osamu; Arai, Nobuaki

2010-01-01

Mitochondrial DNA sequence polymorphisms and patterns of genetic diversity represent the genealogy and relative impacts of historical, geographic, and demographic events on populations. In this study, historical patterns of population dynamics and differentiation in hawksbill (Eretmochelys imbricata) and green turtles (Chelonia mydas) in the Pacific were estimated from feeding populations in the Yaeyama Islands, Japan. Phylogenetic relationships of the haplotypes indicated that hawksbill and green turtles in the Pacific probably underwent very similar patterns and processes of population dynamics over the last million years, with population subdivision during the early Pleistocene and population expansion after the last glacial maximum. These significant contemporary historical events were suggested to have been caused by climatic and sea-level fluctuations. On the other hand, comparing our results to long-term population dynamics in the Atlantic, population subdivisions during the early Pleistocene were specific to Pacific hawksbill and green turtles. Therefore, regional differences in historical population dynamics are suggested. Despite limited sampling locations, these results are the first step in estimating the historical trends in Pacific sea turtles by using phylogenetics and population genetics.

Individual movement behavior, matrix heterogeneity, and the dynamics of spatially structured populations.

PubMed

Revilla, Eloy; Wiegand, Thorsten

2008-12-09

The dynamics of spatially structured populations is characterized by within- and between-patch processes. The available theory describes the latter with simple distance-dependent functions that depend on landscape properties such as interpatch distance or patch size. Despite its potential role, we lack a good mechanistic understanding of how the movement of individuals between patches affects the dynamics of these populations. We used the theoretical framework provided by movement ecology to make a direct representation of the processes determining how individuals connect local populations in a spatially structured population of Iberian lynx. Interpatch processes depended on the heterogeneity of the matrix where patches are embedded and the parameters defining individual movement behavior. They were also very sensitive to the dynamic demographic variables limiting the time moving, the within-patch dynamics of available settlement sites (both spatiotemporally heterogeneous) and the response of individuals to the perceived risk while moving. These context-dependent dynamic factors are an inherent part of the movement process, producing connectivities and dispersal kernels whose variability is affected by other demographic processes. Mechanistic representations of interpatch movements, such as the one provided by the movement-ecology framework, permit the dynamic interaction of birth-death processes and individual movement behavior, thus improving our understanding of stochastic spatially structured populations.

Landscape Pattern Determines Neighborhood Size and Structure within a Lizard Population

PubMed Central

Ryberg, Wade A.; Hill, Michael T.; Painter, Charles W.; Fitzgerald, Lee A.

2013-01-01

Although defining population structure according to discrete habitat patches is convenient for metapopulation theories, taking this approach may overlook structure within populations continuously distributed across landscapes. For example, landscape features within habitat patches direct the movement of organisms and define the density distribution of individuals, which can generate spatial structure and localized dynamics within populations as well as among them. Here, we use the neighborhood concept, which describes population structure relative to the scale of individual movements, to illustrate how localized dynamics within a population of lizards (Sceloporus arenicolus) arise in response to variation in landscape pattern within a continuous habitat patch. Our results emphasize links between individual movements at small scales and the emergence of spatial structure within populations which resembles metapopulation dynamics at larger scales. We conclude that population dynamics viewed in a landscape context must consider the explicit distribution and movement of individuals within continuous habitat as well as among habitat patches. PMID:23441217

Population and Environment

PubMed Central

de Sherbinin, Alex; Carr, David; Cassels, Susan; Jiang, Leiwen

2009-01-01

The interactions between human population dynamics and the environment have often been viewed mechanistically. This review elucidates the complexities and contextual specificities of population-environment relationships in a number of domains. It explores the ways in which demographers and other social scientists have sought to understand the relationships among a full range of population dynamics (e.g., population size, growth, density, age and sex composition, migration, urbanization, vital rates) and environmental changes. The chapter briefly reviews a number of the theories for understanding population and the environment and then proceeds to provide a state-of-the-art review of studies that have examined population dynamics and their relationship to five environmental issue areas. The review concludes by relating population-environment research to emerging work on human-environment systems. PMID:20011237

Antagonisms, mutualisms and commensalisms affect outbreak dynamics of the southern pine beetle

Treesearch

Richard W. Hofstetter; James T. Cronin; Kier D. Klepzig; John C. Moser; Matthew P. Ayres

2005-01-01

Feedback from community interactions involving mutualisms are a rarely explored mechanism for generating complex population dynamics. We examined the effects of two linked mutualisms on the population dynamics of a beetle that exhibits outbreak dynamics. One mutualism involves an obligate association between the bark beetle, Dendroctonus frontalis...

Interactions between demography and environmental effects are important determinants of population dynamics

PubMed Central

Gamelon, Marlène; Grøtan, Vidar; Nilsson, Anna L. K.; Engen, Steinar; Hurrell, James W.; Jerstad, Kurt; Phillips, Adam S.; Røstad, Ole W.; Slagsvold, Tore; Walseng, Bjørn; Stenseth, Nils C.; Sæther, Bernt-Erik

2017-01-01

Climate change will affect the population dynamics of many species, yet the consequences for the long-term persistence of populations are poorly understood. A major reason for this is that density-dependent feedback effects caused by fluctuations in population size are considered independent of stochastic variation in the environment. We show that an interplay between winter temperature and population density can influence the persistence of a small passerine population under global warming. Although warmer winters favor an increased mean population size, density-dependent feedback can cause the local population to be less buffered against occasional poor environmental conditions (cold winters). This shows that it is essential to go beyond the population size and explore climate effects on the full dynamics to elaborate targeted management actions. PMID:28164157

Spatially-Explicit Simulation Modeling of Ecological Response to Climate Change: Methodological Considerations in Predicting Shifting Population Dynamics of Infectious Disease Vectors.

PubMed

Dhingra, Radhika; Jimenez, Violeta; Chang, Howard H; Gambhir, Manoj; Fu, Joshua S; Liu, Yang; Remais, Justin V

2013-09-01

Poikilothermic disease vectors can respond to altered climates through spatial changes in both population size and phenology. Quantitative descriptors to characterize, analyze and visualize these dynamic responses are lacking, particularly across large spatial domains. In order to demonstrate the value of a spatially explicit, dynamic modeling approach, we assessed spatial changes in the population dynamics of Ixodes scapularis , the Lyme disease vector, using a temperature-forced population model simulated across a grid of 4 × 4 km cells covering the eastern United States, using both modeled (Weather Research and Forecasting (WRF) 3.2.1) baseline/current (2001-2004) and projected (Representative Concentration Pathway (RCP) 4.5 and RCP 8.5; 2057-2059) climate data. Ten dynamic population features (DPFs) were derived from simulated populations and analyzed spatially to characterize the regional population response to current and future climate across the domain. Each DPF under the current climate was assessed for its ability to discriminate observed Lyme disease risk and known vector presence/absence, using data from the US Centers for Disease Control and Prevention. Peak vector population and month of peak vector population were the DPFs that performed best as predictors of current Lyme disease risk. When examined under baseline and projected climate scenarios, the spatial and temporal distributions of DPFs shift and the seasonal cycle of key questing life stages is compressed under some scenarios. Our results demonstrate the utility of spatial characterization, analysis and visualization of dynamic population responses-including altered phenology-of disease vectors to altered climate.

Spatially-Explicit Simulation Modeling of Ecological Response to Climate Change: Methodological Considerations in Predicting Shifting Population Dynamics of Infectious Disease Vectors

PubMed Central

Dhingra, Radhika; Jimenez, Violeta; Chang, Howard H.; Gambhir, Manoj; Fu, Joshua S.; Liu, Yang; Remais, Justin V.

2014-01-01

Poikilothermic disease vectors can respond to altered climates through spatial changes in both population size and phenology. Quantitative descriptors to characterize, analyze and visualize these dynamic responses are lacking, particularly across large spatial domains. In order to demonstrate the value of a spatially explicit, dynamic modeling approach, we assessed spatial changes in the population dynamics of Ixodes scapularis, the Lyme disease vector, using a temperature-forced population model simulated across a grid of 4 × 4 km cells covering the eastern United States, using both modeled (Weather Research and Forecasting (WRF) 3.2.1) baseline/current (2001–2004) and projected (Representative Concentration Pathway (RCP) 4.5 and RCP 8.5; 2057–2059) climate data. Ten dynamic population features (DPFs) were derived from simulated populations and analyzed spatially to characterize the regional population response to current and future climate across the domain. Each DPF under the current climate was assessed for its ability to discriminate observed Lyme disease risk and known vector presence/absence, using data from the US Centers for Disease Control and Prevention. Peak vector population and month of peak vector population were the DPFs that performed best as predictors of current Lyme disease risk. When examined under baseline and projected climate scenarios, the spatial and temporal distributions of DPFs shift and the seasonal cycle of key questing life stages is compressed under some scenarios. Our results demonstrate the utility of spatial characterization, analysis and visualization of dynamic population responses—including altered phenology—of disease vectors to altered climate. PMID:24772388

Soybean Yield and Heterodera glycines Population Dynamics as Affected by Cultural Practices in Major Production Areas of the United States and Canada

USDA-ARS?s Scientific Manuscript database

Little information is available on the interactive effects of tillage and row spacing on yield of soybean and population dynamics of H. glycines. This study investigated the effects of rotation of soybean and corn, tillage, row spacing, and cultivar on yield of soybean and population dynamics of H. ...

Stand development and population dynamics of curlleaf mountain mahogany (Cercocarpus ledifolius Nutt.) woodlands in Utah's Bear River Mountains

Treesearch

Seth A. Ex; Robert DeRose; James N. Long

2011-01-01

Curlleaf mountain mahogany (Cercocarpus ledifolius Nutt.) is a little-studied woodland tree that occurs in pure stands throughout the Intermountain West. Stand development and population dynamics of this species are poorly understood, despite their relevance to management. We describe here the development of stand age structures and population dynamics of mahogany...

Strong optical field ionisation of solids

NASA Astrophysics Data System (ADS)

McDonald, C. R.; Ben Taher, A.; Brabec, T.

2017-11-01

Population transfer from the valence to conduction band in the presence of an intense laser field is explored theoretically in semiconductors and dielectrics. Experiments performed on dielectrics exposed to an intense laser field have divulged a population dynamics between valence and conduction band that differs from that observed in semiconductors. Our paper explores two aspects of ionisation in solids. (i) Contemporary ionisation theories do not take account of the coupling between the valence and conduction bands resulting in the absence the dynamic Stark shift. Our single-particle analysis identifies the absence of the dynamic Stark shift as a possible cause for the contrasting ionisation behaviours observed in dielectric and semiconductor materials. The dynamic Stark shift results in an increased bandgap as the laser intensity is increased. This suppresses ionisation to an extent where the main population dynamics results from virtual oscillations in the conduction band population. The dynamic Stark shift mainly affects larger bandgap materials which can be exposed to decidedly higher laser intensities. (ii) In the presence of laser dressed virtual population of the conduction band, elastic collisions potentially transmute virtual into real population resulting in ionisation. This process is explored in the context of the relaxation time approximation.

A Theoretical Approach to Understanding Population Dynamics with Seasonal Developmental Durations

NASA Astrophysics Data System (ADS)

Lou, Yijun; Zhao, Xiao-Qiang

2017-04-01

There is a growing body of biological investigations to understand impacts of seasonally changing environmental conditions on population dynamics in various research fields such as single population growth and disease transmission. On the other side, understanding the population dynamics subject to seasonally changing weather conditions plays a fundamental role in predicting the trends of population patterns and disease transmission risks under the scenarios of climate change. With the host-macroparasite interaction as a motivating example, we propose a synthesized approach for investigating the population dynamics subject to seasonal environmental variations from theoretical point of view, where the model development, basic reproduction ratio formulation and computation, and rigorous mathematical analysis are involved. The resultant model with periodic delay presents a novel term related to the rate of change of the developmental duration, bringing new challenges to dynamics analysis. By investigating a periodic semiflow on a suitably chosen phase space, the global dynamics of a threshold type is established: all solutions either go to zero when basic reproduction ratio is less than one, or stabilize at a positive periodic state when the reproduction ratio is greater than one. The synthesized approach developed here is applicable to broader contexts of investigating biological systems with seasonal developmental durations.

Dancing to the rhythms of the Pleistocene? Early Middle Paleolithic population dynamics in NW Iberia (Duero Basin and Cantabrian Region)

NASA Astrophysics Data System (ADS)

Sánchez Yustos, Policarpo; Diez Martín, Fernando

2015-08-01

The Northwest of Iberia has yielded one of the most complete European Middle Paleolithic records. Despite this wealth of information, very little is known about population dynamics during this period. For that reason, the main concern of this paper is to provide socio-environmental models that may help explain Early Middle Paleolithic (EMP) population dynamics in NW Iberia, assessing to what extent they were shaped by climate forces. The archaeological record is analyzed on the basis of the heuristics of ecological models, already employed in the European Pleistocene record but never at a regional scale, in order to detect long-term changes in the composition of EMP populations, and the environmental, biological and sociocultural process influencing those changes. According to the models proposed, we have detected a long-term population dynamic between MIS 11 and MIS 6, characterized by low environmental stress, high biological productivity, interaction among populations and sociocultural complexity. Eventually, this population dynamic was broken due to an extreme climate phase in late MIS 6 that had a profound impact on populations and sociocultural structures. As a result, the Upper Pleistocene population of NW Iberia was concentrated in the Cantabrian region. This area became an isolated Neanderthal glacial refugium that hosted a population with different origins and fragile long-term demographic stability.

A new ODE tumor growth modeling based on tumor population dynamics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oroji, Amin; Omar, Mohd bin; Yarahmadian, Shantia

2015-10-22

In this paper a new mathematical model for the population of tumor growth treated by radiation is proposed. The cells dynamics population in each state and the dynamics of whole tumor population are studied. Furthermore, a new definition of tumor lifespan is presented. Finally, the effects of two main parameters, treatment parameter (q), and repair mechanism parameter (r) on tumor lifespan are probed, and it is showed that the change in treatment parameter (q) highly affects the tumor lifespan.

Linking extinction-colonization dynamics to genetic structure in a salamander metapopulation.

PubMed

Cosentino, Bradley J; Phillips, Christopher A; Schooley, Robert L; Lowe, Winsor H; Douglas, Marlis R

2012-04-22

Theory predicts that founder effects have a primary role in determining metapopulation genetic structure. However, ecological factors that affect extinction-colonization dynamics may also create spatial variation in the strength of genetic drift and migration. We tested the hypothesis that ecological factors underlying extinction-colonization dynamics influenced the genetic structure of a tiger salamander (Ambystoma tigrinum) metapopulation. We used empirical data on metapopulation dynamics to make a priori predictions about the effects of population age and ecological factors on genetic diversity and divergence among 41 populations. Metapopulation dynamics of A. tigrinum depended on wetland area, connectivity and presence of predatory fish. We found that newly colonized populations were more genetically differentiated than established populations, suggesting that founder effects influenced genetic structure. However, ecological drivers of metapopulation dynamics were more important than age in predicting genetic structure. Consistent with demographic predictions from metapopulation theory, genetic diversity and divergence depended on wetland area and connectivity. Divergence was greatest in small, isolated wetlands where genetic diversity was low. Our results show that ecological factors underlying metapopulation dynamics can be key determinants of spatial genetic structure, and that habitat area and isolation may mediate the contributions of drift and migration to divergence and evolution in local populations.

[Approximation to the dynamics of meningococcal meningitis through dynamic systems and time series].

PubMed

Canals, M

1996-02-01

Meningococcal meningitis is subjected to epidemiological surveillance due to its severity and the occasional presentation of epidemic outbreaks. This work analyses previous disease models, generate new ones and analyses monthly cases using ARIMA time series models. The results show that disease dynamics for closed populations is epidemic and the epidemic size is related to the proportion of carriers and the transmissiveness of the agent. In open populations, disease dynamics depends on the admission rate of susceptible and the relative admission of infected individuals. Our model considers a logistic populational growth and carrier admission proportional to populational size, generating an endemic dynamics. Considering a non-instantaneous system response, a greater realism is obtained establishing that the endemic situation may present a dynamics highly sensitive to initial conditions, depending on the transmissiveness and proportion of susceptible individuals in the population. Time series model showed an adequate predictive capacity in terms no longer than 10 months. The lack of long term predictability was attributed to local changes in the proportion of carriers or on transmissiveness that lead to chaotic dynamics over a seasonal pattern. Predictions for 1995 and 1996 were obtained.

Causes and consequences of complex population dynamics in an annual plant, Cardamine pensylvanica

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crone, E.E.

1995-11-08

The relative importance of density-dependent and density-independent factors in determining the population dynamics of plants has been widely debated with little resolution. In this thesis, the author explores the effects of density-dependent population regulation on population dynamics in Cardamine pensylvanica, an annual plant. In the first chapter, she shows that experimental populations of C. pensylvanica cycled from high to low density in controlled constant-environment conditions. These cycles could not be explained by external environmental changes or simple models of direct density dependence (N{sub t+1} = f[N{sub t}]), but they could be explained by delayed density dependence (N{sub t+1} = f[N{submore » t}, N{sub t+1}]). In the second chapter, she shows that the difference in the stability properties of population growth models with and without delayed density dependence is due to the presence of Hopf as well as slip bifurcations from stable to chaotic population dynamics. She also measures delayed density dependence due to effects of parental density on offspring quality in C. pensylvanica and shows that this is large enough to be the cause of the population dynamics observed in C. pensylvanica. In the third chapter, the author extends her analyses of density-dependent population growth models to include interactions between competing species. In the final chapter, she compares the effects of fixed spatial environmental variation and variation in population size on the evolutionary response of C. pensylvanica populations.« less

Population dynamics on heterogeneous bacterial substrates

NASA Astrophysics Data System (ADS)

Mobius, Wolfram; Murray, Andrew W.; Nelson, David R.

2012-02-01

How species invade new territories and how these range expansions influence the population's genotypes are important questions in the field of population genetics. The majority of work addressing these questions focuses on homogeneous environments. Much less is known about the population dynamics and population genetics when the environmental conditions are heterogeneous in space. To better understand range expansions in two-dimensional heterogeneous environments, we employ a system of bacteria and bacteriophage, the viruses of bacteria. Thereby, the bacteria constitute the environment in which a population of bacteriophages expands. The spread of phage constitutes itself in lysis of bacteria and thus formation of clear regions on bacterial lawns, called plaques. We study the population dynamics and genetics of the expanding page for various patterns of environments.

Plankton Production Biology

DTIC Science & Technology

2013-09-30

kind. It will permit the study of stage-specific population dynamics (growth rate, production, mortality) of copepod larvae in mixed populations...will be picked up. 4. The translation and distribution of Sazhina’s keys will permit the study of stage-specific population dynamics (growth rate...of the 1987 Russian original, edited by K. Banse) Petipa, T.S. (ed.) (1986) Ecological Systems in Dynamically Active Zones of the Indian Ocean

Combined effects of climate, predation, and density dependence on Greater and Lesser Scaup population dynamics

USGS Publications Warehouse

Ross, Beth E.; Hooten, Mevin B.; DeVink, Jean-Michel; Koons, David N.

2015-01-01

An understanding of species relationships is critical in the management and conservation of populations facing climate change, yet few studies address how climate alters species interactions and other population drivers. We use a long-term, broad-scale data set of relative abundance to examine the influence of climate, predators, and density dependence on the population dynamics of declining scaup (Aythya) species within the core of their breeding range. The state-space modeling approach we use applies to a wide range of wildlife species, especially populations monitored over broad spatiotemporal extents. Using this approach, we found that immediate snow cover extent in the preceding winter and spring had the strongest effects, with increases in mean snow cover extent having a positive effect on the local surveyed abundance of scaup. The direct effects of mesopredator abundance on scaup population dynamics were weaker, but the results still indicated a potential interactive process between climate and food web dynamics (mesopredators, alternative prey, and scaup). By considering climate variables and other potential effects on population dynamics, and using a rigorous estimation framework, we provide insight into complex ecological processes for guiding conservation and policy actions aimed at mitigating and reversing the decline of scaup.

Simultaneous effects of food limitation and inducible resistance on herbivore population dynamics.

PubMed

Abbott, Karen C; Morris, William F; Gross, Kevin

2008-02-01

Many herbivore populations fluctuate temporally, but the causes of those fluctuations remain unclear. Plant inducible resistance can theoretically cause herbivore population fluctuations, because herbivory may induce plant changes that reduce the survival or reproduction of later-feeding herbivores. Herbivory can also simply reduce the quantity of food available for later feeders and this, too, can cause population fluctuations. Inducible resistance and food limitation often occur simultaneously, yet whether they jointly facilitate or suppress herbivore fluctuations remains largely unexplored. We present models that suggest that food limitation and inducible resistance may have synergistic effects on herbivore population dynamics. The population-level response of the food plant to herbivory and the details of how inducible resistance affects herbivore performance both influence the resulting herbivore dynamics. Our results identify some biological properties of plant-herbivore systems that might determine whether or not cycles occur, and suggest that future empirical and theoretical population dynamics studies should account for the effects of both food limitation and inducible resistance.

The importance of temperature fluctuations in understanding mosquito population dynamics and malaria risk.

PubMed

Beck-Johnson, Lindsay M; Nelson, William A; Paaijmans, Krijn P; Read, Andrew F; Thomas, Matthew B; Bjørnstad, Ottar N

2017-03-01

Temperature is a key environmental driver of Anopheles mosquito population dynamics; understanding its central role is important for these malaria vectors. Mosquito population responses to temperature fluctuations, though important across the life history, are poorly understood at a population level. We used stage-structured, temperature-dependent delay-differential equations to conduct a detailed exploration of the impacts of diurnal and annual temperature fluctuations on mosquito population dynamics. The model allows exploration of temperature-driven temporal changes in adult age structure, giving insights into the population's capacity to vector malaria parasites. Because of temperature-dependent shifts in age structure, the abundance of potentially infectious mosquitoes varies temporally, and does not necessarily mirror the dynamics of the total adult population. In addition to conducting the first comprehensive theoretical exploration of fluctuating temperatures on mosquito population dynamics, we analysed observed temperatures at four locations in Africa covering a range of environmental conditions. We found both temperature and precipitation are needed to explain the observed malaria season in these locations, enhancing our understanding of the drivers of malaria seasonality and how temporal disease risk may shift in response to temperature changes. This approach, tracking both mosquito abundance and age structure, may be a powerful tool for understanding current and future malaria risk.

Public goods games in populations with fluctuating size.

PubMed

McAvoy, Alex; Fraiman, Nicolas; Hauert, Christoph; Wakeley, John; Nowak, Martin A

2018-05-01

Many mathematical frameworks of evolutionary game dynamics assume that the total population size is constant and that selection affects only the relative frequency of strategies. Here, we consider evolutionary game dynamics in an extended Wright-Fisher process with variable population size. In such a scenario, it is possible that the entire population becomes extinct. Survival of the population may depend on which strategy prevails in the game dynamics. Studying cooperative dilemmas, it is a natural feature of such a model that cooperators enable survival, while defectors drive extinction. Although defectors are favored for any mixed population, random drift could lead to their elimination and the resulting pure-cooperator population could survive. On the other hand, if the defectors remain, then the population will quickly go extinct because the frequency of cooperators steadily declines and defectors alone cannot survive. In a mutation-selection model, we find that (i) a steady supply of cooperators can enable long-term population survival, provided selection is sufficiently strong, and (ii) selection can increase the abundance of cooperators but reduce their relative frequency. Thus, evolutionary game dynamics in populations with variable size generate a multifaceted notion of what constitutes a trait's long-term success. Copyright © 2018 Elsevier Inc. All rights reserved.

The effect of seasonal harvesting on stage-structured population models.

PubMed

Tang, Sanyi; Chen, Lansun

2004-04-01

In most models of population dynamics, increases in population due to birth are assumed to be time-independent, but many species reproduce only during a single period of the year. We propose an exploited single-species model with stage structure for the dynamics in a fish population for which births occur in a single pulse once per time period. Since birth pulse populations are often characterized with a discrete time dynamical system determined by its Poincaré map, we explore the consequences of harvest timing to equilibrium population sizes under seasonal dependence and obtain threshold conditions for their stability, and show that the timing of harvesting has a strong impact on the persistence of the fish population, on the volume of mature fish stock and on the maximum annual-sustainable yield. Moreover, our results imply that the population can sustain much higher harvest rates if the mature fish is removed as early in the season (after the birth pulse) as possible. Further, the effects of harvesting effort and harvest timing on the dynamical complexity are also investigated. Bifurcation diagrams are constructed with the birth rate (or harvesting effort or harvest timing) as the bifurcation parameter, and these are observed to display rich structure, including chaotic bands with periodic windows, pitch-fork and tangent bifurcations, non-unique dynamics (meaning that several attractors coexist) and attractor crisis. This suggests that birth pulse, in effect, provides a natural period or cyclicity that makes the dynamical behavior more complex.

Soil-related variations in the population dynamics of six dipterocarp tree species with strong habitat preferences.

PubMed

Yamada, Toshihiro; Yamada, Yuko; Okuda, Toshinori; Fletcher, Christine

2013-07-01

Differences in the density of conspecific tree individuals in response to environmental gradients are well documented for many tree species, but how such density differences are generated and maintained is poorly understood. We examined the segregation of six dipterocarp species among three soil types in the Pasoh tropical forest, Malaysia. We examined how individual performance and population dynamics changed across the soil types using 10-year demographic data to compare tree performance across soil types, and constructed population matrix models to analyze the population dynamics. Species showed only minor changes in mortality and juvenile growth across soil types, although recruitment differed greatly. Clear, interspecific demographic trade-offs between growth and mortality were found in all soil types. The relative trade-offs by a species did not differ substantially among the soil types. Population sizes were projected to remain stable in all soil types for all species with one exception. Our life-table response experiment demonstrated that the population dynamics of a species differed only subtly among soil types. Therefore, species with strong density differences across soil types do not necessarily differ greatly in their population dynamics across the soil types. In contrast, interspecific differences in population dynamics were large. The trade-off between mortality and growth led to a negative correlation between the contributions of mortality and growth to variations in the population growth rate (λ) and thus reduced their net contributions. Recruitment had little impact on the variation in λ. The combination of these factors resulted in little variation in λ among species.

Capital, population and urban patterns.

PubMed

Zhang, W

1994-04-01

The author develops an approach to urban dynamics with endogenous capital and population growth, synthesizing the Alonso location model, the two-sector neoclassical growth model, and endogenous population theory. A dynamic model for an isolated island economy with endogenous capital, population, and residential structure is developed on the basis of Alonso's residential model and the two-sector neoclassical growth model. The model describes the interdependence between residential structure, economic growth, population growth, and economic structure over time and space. It has a unique long-run equilibrium, which may be either stable or unstable, depending upon the population dynamics. Applying the Hopf theorem, the author also shows that when the system is unstable, the economic geography exhibits permanent endogenous oscillations.

Stochastic population dynamics in populations of western terrestrial garter snakes with divergent life histories

USGS Publications Warehouse

Miller, David A.; Clark, W.R.; Arnold, S.J.; Bronikowski, A.M.

2011-01-01

Comparative evaluations of population dynamics in species with temporal and spatial variation in life-history traits are rare because they require long-term demographic time series from multiple populations. We present such an analysis using demographic data collected during the interval 1978-1996 for six populations of western terrestrial garter snakes (Thamnophis elegans) from two evolutionarily divergent ecotypes. Three replicate populations from a slow-living ecotype, found in mountain meadows of northeastern California, were characterized by individuals that develop slowly, mature late, reproduce infrequently with small reproductive effort, and live longer than individuals of three populations of a fast-living ecotype found at lakeshore locales. We constructed matrix population models for each of the populations based on 8-13 years of data per population and analyzed both deterministic dynamics based on mean annual vital rates and stochastic dynamics incorporating annual variation in vital rates. (1) Contributions of highly variable vital rates to fitness (??s) were buffered against the negative effects of stochastic variation, and this relationship was consistent with differences between the meadow (M-slow) and lakeshore (L-fast) ecotypes. (2) Annual variation in the proportion of gravid females had the greatest negative effect among all vital rates on ?? s. The magnitude of variation in the proportion of gravid females and its effect on ??s was greater in M-slow than L-fast populations. (3) Variation in the proportion of gravid females, in turn, depended on annual variation in prey availability, and its effect on ??s was 4- 23 times greater in M-slow than L-fast populations. In addition to differences in stochastic dynamics between ecotypes, we also found higher mean mortality rates across all age classes in the L-fast populations. Our results suggest that both deterministic and stochastic selective forces have affected the evolution of divergent life-history traits in the two ecotypes, which, in turn, affect population dynamics. M-slow populations have evolved life-history traits that buffer fitness against direct effects of variation in reproduction and that spread lifetime reproduction across a greater number of reproductive bouts. These results highlight the importance of long-term demographic and environmental monitoring and of incorporating temporal dynamics into empirical studies of life-history evolution. ?? 2011 by the Ecological Society of America.

Stochastic population dynamics in populations of western terrestrial garter snakes with divergent life histories.

PubMed

Miller, David A; Clark, William R; Arnold, Stevan J; Bronikowski, Anne M

2011-08-01

Comparative evaluations of population dynamics in species with temporal and spatial variation in life-history traits are rare because they require long-term demographic time series from multiple populations. We present such an analysis using demographic data collected during the interval 1978-1996 for six populations of western terrestrial garter snakes (Thamnophis elegans) from two evolutionarily divergent ecotypes. Three replicate populations from a slow-living ecotype, found in mountain meadows of northeastern California, were characterized by individuals that develop slowly, mature late, reproduce infrequently with small reproductive effort, and live longer than individuals of three populations of a fast-living ecotype found at lakeshore locales. We constructed matrix population models for each of the populations based on 8-13 years of data per population and analyzed both deterministic dynamics based on mean annual vital rates and stochastic dynamics incorporating annual variation in vital rates. (1) Contributions of highly variable vital rates to fitness (lambda(s)) were buffered against the negative effects of stochastic variation, and this relationship was consistent with differences between the meadow (M-slow) and lakeshore (L-fast) ecotypes. (2) Annual variation in the proportion of gravid females had the greatest negative effect among all vital rates on lambda(s). The magnitude of variation in the proportion of gravid females and its effect on lambda(s) was greater in M-slow than L-fast populations. (3) Variation in the proportion of gravid females, in turn, depended on annual variation in prey availability, and its effect on lambda(s) was 4 23 times greater in M-slow than L-fast populations. In addition to differences in stochastic dynamics between ecotypes, we also found higher mean mortality rates across all age classes in the L-fast populations. Our results suggest that both deterministic and stochastic selective forces have affected the evolution of divergent life-history traits in the two ecotypes, which, in turn, affect population dynamics. M-slow populations have evolved life-history traits that buffer fitness against direct effects of variation in reproduction and that spread lifetime reproduction across a greater number of reproductive bouts. These results highlight the importance of long-term demographic and environmental monitoring and of incorporating temporal dynamics into empirical studies of life-history evolution.

Evolutionary dynamics of fearfulness and boldness.

PubMed

Ji, Ting; Zhang, Boyu; Sun, Yuehua; Tao, Yi

2009-02-21

A negative relationship between reproductive effort and survival is consistent with life-history. Evolutionary dynamics and evolutionarily stable strategy (ESS) for the trade-off between survival and reproduction are investigated using a simple model with two phenotypes, fearfulness and boldness. The dynamical stability of the pure strategy model and analysis of ESS conditions reveal that: (i) the simple coexistence of fearfulness and boldness is impossible; (ii) a small population size is favorable to fearfulness, but a large population size is favorable to boldness, i.e., neither fearfulness, nor boldness is always favored by natural selection; and (iii) the dynamics of population density is crucial for a proper understanding of the strategy dynamics.

Recent range expansion of a terrestrial orchid corresponds with climate-driven variation in its population dynamics.

PubMed

van der Meer, Sascha; Jacquemyn, Hans; Carey, Peter D; Jongejans, Eelke

2016-06-01

The population dynamics and distribution limits of plant species are predicted to change as the climate changes. However, it remains unclear to what extent climate variables affect population dynamics, which vital rates are most sensitive to climate change, and whether the same vital rates drive population dynamics in different populations. In this study, we used long-term demographic data from two populations of the terrestrial orchid Himantoglossum hircinum growing at the northern edge of their geographic range to quantify the influence of climate change on demographic vital rates. Integral projection models were constructed to study how climate conditions between 1991 and 2006 affected population dynamics and to assess how projected future climate change will affect the long-term viability of this species. Based on the parameterised vital rate functions and the observed climatic conditions, one of the studied populations had an average population growth rate above 1 (λ = 1.04), while the other was declining at ca. 3 % year(-1) (λ = 0.97). Variation in temperature and precipitation mainly affected population growth through their effect on survival and fecundity. Based on UK Climate Projection 2009 estimates of future climate conditions for three greenhouse gas emission scenarios, population growth rates are expected to increase in one of the studied populations. Overall, our results indicate that the observed changes in climatic conditions appeared to be beneficial to the long-term survival of the species in the UK and suggest that they may have been the driving force behind the current range expansion of H. hircinum in England.

Using dynamic population simulations to extend resource selection analyses and prioritize habitats for conservation

USGS Publications Warehouse

Heinrichs, Julie; Aldridge, Cameron L.; O'Donnell, Michael; Schumaker, Nathan

2017-01-01

Prioritizing habitats for conservation is a challenging task, particularly for species with fluctuating populations and seasonally dynamic habitat needs. Although the use of resource selection models to identify and prioritize habitat for conservation is increasingly common, their ability to characterize important long-term habitats for dynamic populations are variable. To examine how habitats might be prioritized differently if resource selection was directly and dynamically linked with population fluctuations and movement limitations among seasonal habitats, we constructed a spatially explicit individual-based model for a dramatically fluctuating population requiring temporally varying resources. Using greater sage-grouse (Centrocercus urophasianus) in Wyoming as a case study, we used resource selection function maps to guide seasonal movement and habitat selection, but emergent population dynamics and simulated movement limitations modified long-term habitat occupancy. We compared priority habitats in RSF maps to long-term simulated habitat use. We examined the circumstances under which the explicit consideration of movement limitations, in combination with population fluctuations and trends, are likely to alter predictions of important habitats. In doing so, we assessed the future occupancy of protected areas under alternative population and habitat conditions. Habitat prioritizations based on resource selection models alone predicted high use in isolated parcels of habitat and in areas with low connectivity among seasonal habitats. In contrast, results based on more biologically-informed simulations emphasized central and connected areas near high-density populations, sometimes predicted to be low selection value. Dynamic models of habitat use can provide additional biological realism that can extend, and in some cases, contradict habitat use predictions generated from short-term or static resource selection analyses. The explicit inclusion of population dynamics and movement propensities via spatial simulation modeling frameworks may provide an informative means of predicting long-term habitat use, particularly for fluctuating populations with complex seasonal habitat needs. Importantly, our results indicate the possible need to consider habitat selection models as a starting point rather than the common end point for refining and prioritizing habitats for protection for cyclic and highly variable populations.

Single-trial dynamics of motor cortex and their applications to brain-machine interfaces

PubMed Central

Kao, Jonathan C.; Nuyujukian, Paul; Ryu, Stephen I.; Churchland, Mark M.; Cunningham, John P.; Shenoy, Krishna V.

2015-01-01

Increasing evidence suggests that neural population responses have their own internal drive, or dynamics, that describe how the neural population evolves through time. An important prediction of neural dynamical models is that previously observed neural activity is informative of noisy yet-to-be-observed activity on single-trials, and may thus have a denoising effect. To investigate this prediction, we built and characterized dynamical models of single-trial motor cortical activity. We find these models capture salient dynamical features of the neural population and are informative of future neural activity on single trials. To assess how neural dynamics may beneficially denoise single-trial neural activity, we incorporate neural dynamics into a brain–machine interface (BMI). In online experiments, we find that a neural dynamical BMI achieves substantially higher performance than its non-dynamical counterpart. These results provide evidence that neural dynamics beneficially inform the temporal evolution of neural activity on single trials and may directly impact the performance of BMIs. PMID:26220660

Population ecology of insect invasions and their management

Treesearch

Andrew M. Liebhold; Patrick C. Tobin

2008-01-01

During the establishment phase of a biological invasion, population dynamics are strongly influenced by Allee effects and stochastic dynamics, both of which may lead to extinction of low-density populations. Allee effects refer to a decline in population growth rate with a decline in abundance and can arise from various mechanisms. Strategies to eradicate newly...

Leading edge gypsy moth population dynamics

Treesearch

M. R. Carter; F. W. Ravlin; M. L. McManus

1991-01-01

Leading edge gypsy moth populations have been the focus of several intervention programs (MDIPM, AIPM). Knowledge of gypsy moth population dynamics in leading edge area is crucial for effective management. Populations in these areas tend to reach outbreak levels (noticeable defoliation) within three to four years after egg masses are first detected. Pheromone traps...

Environmental variability and population dynamics: Do European and North American ducks play by the same rules?

USGS Publications Warehouse

Pöysä, Hannu; Rintala, Jukka; Johnson, Douglas H.; Kauppinen, Jukka; Lammi, Esa; Nudds, Thomas D.; Väänänen, Veli-Matti

2016-01-01

Density dependence, population regulation, and variability in population size are fundamental population processes, the manifestation and interrelationships of which are affected by environmental variability. However, there are surprisingly few empirical studies that distinguish the effect of environmental variability from the effects of population processes. We took advantage of a unique system, in which populations of the same duck species or close ecological counterparts live in highly variable (north American prairies) and in stable (north European lakes) environments, to distinguish the relative contributions of environmental variability (measured as between-year fluctuations in wetland numbers) and intraspecific interactions (density dependence) in driving population dynamics. We tested whether populations living in stable environments (in northern Europe) were more strongly governed by density dependence than populations living in variable environments (in North America). We also addressed whether relative population dynamical responses to environmental variability versus density corresponded to differences in life history strategies between dabbling (relatively “fast species” and governed by environmental variability) and diving (relatively “slow species” and governed by density) ducks. As expected, the variance component of population fluctuations caused by changes in breeding environments was greater in North America than in Europe. Contrary to expectations, however, populations in more stable environments were not less variable nor clearly more strongly density dependent than populations in highly variable environments. Also, contrary to expectations, populations of diving ducks were neither more stable nor stronger density dependent than populations of dabbling ducks, and the effect of environmental variability on population dynamics was greater in diving than in dabbling ducks. In general, irrespective of continent and species life history, environmental variability contributed more to variation in species abundances than did density. Our findings underscore the need for more studies on populations of the same species in different environments to verify the generality of current explanations about population dynamics and its association with species life history.

Environmental variability and population dynamics: do European and North American ducks play by the same rules?

PubMed

Pöysä, Hannu; Rintala, Jukka; Johnson, Douglas H; Kauppinen, Jukka; Lammi, Esa; Nudds, Thomas D; Väänänen, Veli-Matti

2016-10-01

Density dependence, population regulation, and variability in population size are fundamental population processes, the manifestation and interrelationships of which are affected by environmental variability. However, there are surprisingly few empirical studies that distinguish the effect of environmental variability from the effects of population processes. We took advantage of a unique system, in which populations of the same duck species or close ecological counterparts live in highly variable (north American prairies) and in stable (north European lakes) environments, to distinguish the relative contributions of environmental variability (measured as between-year fluctuations in wetland numbers) and intraspecific interactions (density dependence) in driving population dynamics. We tested whether populations living in stable environments (in northern Europe) were more strongly governed by density dependence than populations living in variable environments (in North America). We also addressed whether relative population dynamical responses to environmental variability versus density corresponded to differences in life history strategies between dabbling (relatively "fast species" and governed by environmental variability) and diving (relatively "slow species" and governed by density) ducks. As expected, the variance component of population fluctuations caused by changes in breeding environments was greater in North America than in Europe. Contrary to expectations, however, populations in more stable environments were not less variable nor clearly more strongly density dependent than populations in highly variable environments. Also, contrary to expectations, populations of diving ducks were neither more stable nor stronger density dependent than populations of dabbling ducks, and the effect of environmental variability on population dynamics was greater in diving than in dabbling ducks. In general, irrespective of continent and species life history, environmental variability contributed more to variation in species abundances than did density. Our findings underscore the need for more studies on populations of the same species in different environments to verify the generality of current explanations about population dynamics and its association with species life history.

SPATIAL SCALE OF AUTOCORRELATION IN WISCONSIN FROG AND TOAD SURVEY DATA

EPA Science Inventory

The degree to which local population dynamics are correlated with nearby sites has important implications for metapopulation dynamics and landscape management. Spatially extensive monitoring data can be used to evaluate large-scale population dynamic processes. Our goals in this ...

AN INDIVIDUAL-BASED MODEL OF COTTUS POPULATION DYNAMICS

EPA Science Inventory

We explored population dynamics of a southern Appalachian population of Cottus bairdi using a spatially-explicit, individual-based model. The model follows daily growth, mortality, and spawning of individuals as a function of flow and temperature. We modeled movement of juveniles...

Evolutionary dynamics of cooperation in neutral populations

NASA Astrophysics Data System (ADS)

Szolnoki, Attila; Perc, Matjaž

2018-01-01

Cooperation is a difficult proposition in the face of Darwinian selection. Those that defect have an evolutionary advantage over cooperators who should therefore die out. However, spatial structure enables cooperators to survive through the formation of homogeneous clusters, which is the hallmark of network reciprocity. Here we go beyond this traditional setup and study the spatiotemporal dynamics of cooperation in a population of populations. We use the prisoner's dilemma game as the mathematical model and show that considering several populations simultaneously gives rise to fascinating spatiotemporal dynamics and pattern formation. Even the simplest assumption that strategies between different populations are payoff-neutral with one another results in the spontaneous emergence of cyclic dominance, where defectors of one population become prey of cooperators in the other population, and vice versa. Moreover, if social interactions within different populations are characterized by significantly different temptations to defect, we observe that defectors in the population with the largest temptation counterintuitively vanish the fastest, while cooperators that hang on eventually take over the whole available space. Our results reveal that considering the simultaneous presence of different populations significantly expands the complexity of evolutionary dynamics in structured populations, and it allows us to understand the stability of cooperation under adverse conditions that could never be bridged by network reciprocity alone.

Long-term dynamics of natural populations of Schistosoma mansoni among Rattus rattus in patchy environment.

PubMed

Théron, A; Pointier, J P; Morand, S; Imbert-Establet, D; Borel, G

1992-04-01

Dynamics of natural populations of Schistosoma mansoni were studied during 8 consecutive years among Rattus rattus populations from 8 transmission sites of the marshy forest focus of Guadeloupe (French West Indies). The schistosome population is over-dispersed (k = 0.119) within the murine hosts and ecological factors linked to the patchy environment may be responsible for such aggregated distribution. Analysis of the spatio-temporal variations in prevalences, intensities and abundances showed limited variations of the infection during the 8 years at the level of the whole parasite population but great spatial heterogeneity at the level of local schistosome populations. Inter-populational genetic variability linked to the degree of adaptation of this human parasite to the murine host may explain differences in transmission dynamics between the local populations of S. mansoni.

Evolutionary Game Theory in Growing Populations

NASA Astrophysics Data System (ADS)

Melbinger, Anna; Cremer, Jonas; Frey, Erwin

2010-10-01

Existing theoretical models of evolution focus on the relative fitness advantages of different mutants in a population while the dynamic behavior of the population size is mostly left unconsidered. We present here a generic stochastic model which combines the growth dynamics of the population and its internal evolution. Our model thereby accounts for the fact that both evolutionary and growth dynamics are based on individual reproduction events and hence are highly coupled and stochastic in nature. We exemplify our approach by studying the dilemma of cooperation in growing populations and show that genuinely stochastic events can ease the dilemma by leading to a transient but robust increase in cooperation.

Multi-Point Hermes Acoustic Modem for High-Speed, High-Frequency Acoustic Communications with Low-Frequency Acoustic Control Loop for Real-Time Transmission of AUV-Carried High-Resolution Images and Navigation Data in Support of Ship Hulls Inspection

DTIC Science & Technology

2013-08-31

13.3 µs) used in the data frame. The preamble uses direct-sequence spread spectrum (DSSS) to reduce the negative impact of fading. Three bits... ifr t covers one of the allocated hops of index  h i . The received reference symbol transmitted in hop   1,2,..., Hh i N is    ( )h...are recovered based on the phase difference between the constellation points demodulated from the sub-band m of the information symbol  ( ) ifr t

Identification of volatile components of bobcat (Lynx rufus) urine.

PubMed

Mattina, M J; Pignatello, J J; Swihart, R K

1991-02-01

Bobcat (Lynx rufus) urine reduces scent-marking activity of woodchucks (Marmota monax) and feeding activity of snowshoe hares (Lepus americanus) and deer (Odocoileus virginianus, O. hemionus). In order to identify the semiochemicals responsible for these behavior modifications, a dichloromethane extract of the bobcat urine was analyzed by GC-MS. Among the known compounds identified in the extract are phenol, indole, dimethyl sulfone, and 3-mercapto-3-methylbutanol. Compounds for which spectroscopic data are presented for the first time include one sulfide, two disulfides, and two trisulfides. The sulfur compounds are derived from an amino acid,S-(l,1-dimethyl-3-hydroxypropyl)cysteine ("felinine"), which was identified several years ago in the urine of the domestic cat (Felis domesticus).

[The dynamics of heath indicators of population of industrial town].

PubMed

Kalinkin, D E; Karpov, A B; Takhauov, R M; Samoĭlova, Iu A

2013-01-01

The article presents the results of analysis of dynamics of health indicators of population of industrial town (medical demographic indicators, disability, morbidity of social hygienically important diseases) during 1970-2010. The classified administrative territorial municipality of Seversk constructed near the Siberian chemical industrial center, the internationally first-rate complex of nuclear industry enterprises was used as a research base. It is demonstrated that dynamics of health indicators of studied population had such negative tendencies as rapid population ageing, population loss due to decrease of natality and increase of mortality (population of able-bodied age included), prevalence of cardio-vascular diseases, malignant neoplasms and external causes, chronization of diseases. The established tendencies are to be considered in management decision making targeted to support and promote population health in industrial towns.

Population-reaction model and microbial experimental ecosystems for understanding hierarchical dynamics of ecosystems.

PubMed

Hosoda, Kazufumi; Tsuda, Soichiro; Kadowaki, Kohmei; Nakamura, Yutaka; Nakano, Tadashi; Ishii, Kojiro

2016-02-01

Understanding ecosystem dynamics is crucial as contemporary human societies face ecosystem degradation. One of the challenges that needs to be recognized is the complex hierarchical dynamics. Conventional dynamic models in ecology often represent only the population level and have yet to include the dynamics of the sub-organism level, which makes an ecosystem a complex adaptive system that shows characteristic behaviors such as resilience and regime shifts. The neglect of the sub-organism level in the conventional dynamic models would be because integrating multiple hierarchical levels makes the models unnecessarily complex unless supporting experimental data are present. Now that large amounts of molecular and ecological data are increasingly accessible in microbial experimental ecosystems, it is worthwhile to tackle the questions of their complex hierarchical dynamics. Here, we propose an approach that combines microbial experimental ecosystems and a hierarchical dynamic model named population-reaction model. We present a simple microbial experimental ecosystem as an example and show how the system can be analyzed by a population-reaction model. We also show that population-reaction models can be applied to various ecological concepts, such as predator-prey interactions, climate change, evolution, and stability of diversity. Our approach will reveal a path to the general understanding of various ecosystems and organisms. Copyright © 2015 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Exploring Population Admixture Dynamics via Empirical and Simulated Genome-wide Distribution of Ancestral Chromosomal Segments

PubMed Central

Jin, Wenfei; Wang, Sijia; Wang, Haifeng; Jin, Li; Xu, Shuhua

2012-01-01

The processes of genetic admixture determine the haplotype structure and linkage disequilibrium patterns of the admixed population, which is important for medical and evolutionary studies. However, most previous studies do not consider the inherent complexity of admixture processes. Here we proposed two approaches to explore population admixture dynamics, and we demonstrated, by analyzing genome-wide empirical and simulated data, that the approach based on the distribution of chromosomal segments of distinct ancestry (CSDAs) was more powerful than that based on the distribution of individual ancestry proportions. Analysis of 1,890 African Americans showed that a continuous gene flow model, in which the African American population continuously received gene flow from European populations over about 14 generations, best explained the admixture dynamics of African Americans among several putative models. Interestingly, we observed that some African Americans had much more European ancestry than the simulated samples, indicating substructures of local ancestries in African Americans that could have been caused by individuals from some particular lineages having repeatedly admixed with people of European ancestry. In contrast, the admixture dynamics of Mexicans could be explained by a gradual admixture model in which the Mexican population continuously received gene flow from both European and Amerindian populations over about 24 generations. Our results also indicated that recent gene flows from Sub-Saharan Africans have contributed to the gene pool of Middle Eastern populations such as Mozabite, Bedouin, and Palestinian. In summary, this study not only provides approaches to explore population admixture dynamics, but also advances our understanding on population history of African Americans, Mexicans, and Middle Eastern populations. PMID:23103229

POPULATION DYNAMICS OF HISPID COTTON RATS (SIGMODON HISPIDUS) ACROSS A NITROGEN AMENDED LANDSCAPE

EPA Science Inventory

Population dynamics of some small-mammal species appear to be regulated by plant-community structure, vegetative cover, plant diversity, and food quality. Thus, plant community changes associated with nitrogen additions would likely impact dynamics and structure of small-mammal ...

Regional Population Dynamics

Treesearch

Andrew Birt

2011-01-01

The population dynamics of the southern pine beetle (SPB) exhibit characteristic fluctuations between relatively long endemic and shorter outbreak periods. Populations exhibit complex and hierarchical spatial structure with beetles and larvae aggregating within individual trees, infestations with multiple infested trees, and regional outbreaks that comprise a large...

Structural stability of nonlinear population dynamics.

PubMed

Cenci, Simone; Saavedra, Serguei

2018-01-01

In population dynamics, the concept of structural stability has been used to quantify the tolerance of a system to environmental perturbations. Yet, measuring the structural stability of nonlinear dynamical systems remains a challenging task. Focusing on the classic Lotka-Volterra dynamics, because of the linearity of the functional response, it has been possible to measure the conditions compatible with a structurally stable system. However, the functional response of biological communities is not always well approximated by deterministic linear functions. Thus, it is unclear the extent to which this linear approach can be generalized to other population dynamics models. Here, we show that the same approach used to investigate the classic Lotka-Volterra dynamics, which is called the structural approach, can be applied to a much larger class of nonlinear models. This class covers a large number of nonlinear functional responses that have been intensively investigated both theoretically and experimentally. We also investigate the applicability of the structural approach to stochastic dynamical systems and we provide a measure of structural stability for finite populations. Overall, we show that the structural approach can provide reliable and tractable information about the qualitative behavior of many nonlinear dynamical systems.

Structural stability of nonlinear population dynamics

NASA Astrophysics Data System (ADS)

Cenci, Simone; Saavedra, Serguei

2018-01-01

In population dynamics, the concept of structural stability has been used to quantify the tolerance of a system to environmental perturbations. Yet, measuring the structural stability of nonlinear dynamical systems remains a challenging task. Focusing on the classic Lotka-Volterra dynamics, because of the linearity of the functional response, it has been possible to measure the conditions compatible with a structurally stable system. However, the functional response of biological communities is not always well approximated by deterministic linear functions. Thus, it is unclear the extent to which this linear approach can be generalized to other population dynamics models. Here, we show that the same approach used to investigate the classic Lotka-Volterra dynamics, which is called the structural approach, can be applied to a much larger class of nonlinear models. This class covers a large number of nonlinear functional responses that have been intensively investigated both theoretically and experimentally. We also investigate the applicability of the structural approach to stochastic dynamical systems and we provide a measure of structural stability for finite populations. Overall, we show that the structural approach can provide reliable and tractable information about the qualitative behavior of many nonlinear dynamical systems.

Metapopulation dynamics and the evolution of dispersal

NASA Astrophysics Data System (ADS)

Parvinen, Kalle

A metapopulation consists of local populations living in habitat patches. In this chapter metapopulation dynamics and the evolution of dispersal is studied in two metapopulation models defined in discrete time. In the first model there are finitely many patches, and in the other one there are infinitely many patches, which allows to incorporate catastrophes into the model. In the first model, cyclic local population dynamics can be either synchronized or not, and increasing dispersal both synchronizes and stabilizes metapopulation dynamics. On the other hand, the type of dynamics has a strong effect on the evolution of dispersal. In case of non-synchronized metapopulation dynamics, dispersal is much more beneficial than in the case of synchronized metapopulation dynamics. Local dynamics has a substantial effect also on the possibility of evolutionary branching in both models. Furthermore, with an Allee effect in the local dynamics of the second model, even evolutionary suicide can occur. It is an evolutionary process in which a viable population adapts in such a way that it can no longer persist.

Impact of transient climate change upon Grouse population dynamics in the Italian Alps

NASA Astrophysics Data System (ADS)

Pirovano, Andrea; Bocchiola, Daniele

2010-05-01

Understanding the effect of short to medium term weather condition, and of transient global warming upon wildlife species life history is essential to predict the demographic consequences therein, and possibly develop adaptation strategies, especially in game species, where hunting mortality may play an important role in population dynamics. We carried out a preliminary investigation of observed impact of weather variables upon population dynamics indexes of three alpine Grouse species (i.e. Rock Ptarmigan, Lagopus Mutus, Black Grouse, Tetrao Tetrix, Rock Partridge, Alectoris Graeca), nested within central Italian Alps, based upon 15 years (1995-2009) of available censuses data, provided by the Sondrio Province authority. We used a set of climate variables already highlighted within recent literature for carrying considerable bearing on Grouse population dynamics, including e.g. temperature at hatching time and during winter, snow cover at nesting, and precipitation during nursing period. We then developed models of Grouses' population dynamics by explicitly driving population change according to their dependence upon the significant weather variables and population density and we evaluated objective indexes to assess the so obtained predictive power. Eventually, we develop projection of future local climate, based upon locally derived trends, and upon projections from GCMs (A2 IPCC storyline) already validated for the area, to project forward in time (until 2100 or so) the significant climatic variables, which we then use to force population dynamics models of the target species. The projected patterns obtained through this exercise are discussed and compared against those expected under stationary climate conditions at present, and preliminary conclusions are drawn.

The Analysis of Cell Population Dynamics in Mammary Gland Development and Tumorigenesis

DTIC Science & Technology

2005-08-01

AD Award Number: DAMD17-03-1-0498 TITLE: The Analysis of Cell Population Dynamics in Mammary Gland Development and Tumorigenesis PRINCIPAL...Summary 1 Aug 2004 - 31 Jul 2005 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER The Analysis of Cell Population Dynamics in Mammary Gland Development and...STATEMENT Approved for Public Release; Distribution Unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT The mammary gland is made up of several epithelial cell

Stochastic hybrid delay population dynamics: well-posed models and extinction.

PubMed

Yuan, Chenggui; Mao, Xuerong; Lygeros, John

2009-01-01

Nonlinear differential equations have been used for decades for studying fluctuations in the populations of species, interactions of species with the environment, and competition and symbiosis between species. Over the years, the original non-linear models have been embellished with delay terms, stochastic terms and more recently discrete dynamics. In this paper, we investigate stochastic hybrid delay population dynamics (SHDPD), a very general class of population dynamics that comprises all of these phenomena. For this class of systems, we provide sufficient conditions to ensure that SHDPD have global positive, ultimately bounded solutions, a minimum requirement for a realistic, well-posed model. We then study the question of extinction and establish conditions under which an ecosystem modelled by SHDPD is doomed.

Slow and fast dynamics model of a Malaria with Sickle-Cell genetic disease with multi-stage infections of the mosquitoes population

NASA Astrophysics Data System (ADS)

Dewi Siawanta, Shanti; Adi-Kusumo, Fajar; Irwan Endrayanto, Aluicius

2018-03-01

Malaria, which is caused by Plasmodium, is a common disease in tropical areas. There are three types of Plasmodium i.e. Plasmodium Vivax, Plasmodium Malariae, and Plasmodium Falciparum. The most dangerous cases of the Malaria are mainly caused by the Plasmodium Falciparum. One of the important characteristics for the Plasmodium infection is due to the immunity of erythrocyte that contains HbS (Haemoglobin Sickle-cell) genes. The individuals who has the HbS gene has better immunity against the disease. In this paper, we consider a model that shows the spread of malaria involving the interaction between the mosquitos population, the human who has HbS genes population and the human with normal gene population. We do some analytical and numerical simulation to study the basic reproduction ratio and the slow-fast dynamics of the phase-portrait. The slow dynamics in our model represents the response of the human population with HbS gene to the Malaria disease while the fast dynamics show the response of the human population with the normal gene to the disease. The slow and fast dynamics phenomena are due to the fact that the population of the individuals who have HbS gene is much smaller than the individuals who has normal genes.

Elevated nonlinearity as an indicator of shifts in the dynamics of populations under stress.

PubMed

Dakos, Vasilis; Glaser, Sarah M; Hsieh, Chih-Hao; Sugihara, George

2017-03-01

Populations occasionally experience abrupt changes, such as local extinctions, strong declines in abundance or transitions from stable dynamics to strongly irregular fluctuations. Although most of these changes have important ecological and at times economic implications, they remain notoriously difficult to detect in advance. Here, we study changes in the stability of populations under stress across a variety of transitions. Using a Ricker-type model, we simulate shifts from stable point equilibrium dynamics to cyclic and irregular boom-bust oscillations as well as abrupt shifts between alternative attractors. Our aim is to infer the loss of population stability before such shifts based on changes in nonlinearity of population dynamics. We measure nonlinearity by comparing forecast performance between linear and nonlinear models fitted on reconstructed attractors directly from observed time series. We compare nonlinearity to other suggested leading indicators of instability (variance and autocorrelation). We find that nonlinearity and variance increase in a similar way prior to the shifts. By contrast, autocorrelation is strongly affected by oscillations. Finally, we test these theoretical patterns in datasets of fisheries populations. Our results suggest that elevated nonlinearity could be used as an additional indicator to infer changes in the dynamics of populations under stress. © 2017 The Author(s).

Climate effects and feedback structure determining weed population dynamics in a long-term experiment.

PubMed

Lima, Mauricio; Navarrete, Luis; González-Andujar, José Luis

2012-01-01

Pest control is one of the areas in which population dynamic theory has been successfully applied to solve practical problems. However, the links between population dynamic theory and model construction have been less emphasized in the management and control of weed populations. Most management models of weed population dynamics have emphasized the role of the endogenous process, but the role of exogenous variables such as climate have been ignored in the study of weed populations and their management. Here, we use long-term data (22 years) on two annual weed species from a locality in Central Spain to determine the importance of endogenous and exogenous processes (local and large-scale climate factors). Our modeling study determined two different feedback structures and climate effects in the two weed species analyzed. While Descurainia sophia exhibited a second-order feedback and low climate influence, Veronica hederifolia was characterized by a first-order feedback structure and important effects from temperature and rainfall. Our results strongly suggest the importance of theoretical population dynamics in understanding plant population systems. Moreover, the use of this approach, discerning between the effect of exogenous and endogenous factors, can be fundamental to applying weed management practices in agricultural systems and to controlling invasive weedy species. This is a radical change from most approaches currently used to guide weed and invasive weedy species managements.

Dynamic Properties of the Alkaline Vesicle Population at Hippocampal Synapses

PubMed Central

Röther, Mareike; Brauner, Jan M.; Ebert, Katrin; Welzel, Oliver; Jung, Jasmin; Bauereiss, Anna; Kornhuber, Johannes; Groemer, Teja W.

2014-01-01

In compensatory endocytosis, scission of vesicles from the plasma membrane to the cytoplasm is a prerequisite for intravesicular reacidification and accumulation of neurotransmitter molecules. Here, we provide time-resolved measurements of the dynamics of the alkaline vesicle population which appears upon endocytic retrieval. Using fast perfusion pH-cycling in live-cell microscopy, synapto-pHluorin expressing rat hippocampal neurons were electrically stimulated. We found that the relative size of the alkaline vesicle population depended significantly on the electrical stimulus size: With increasing number of action potentials the relative size of the alkaline vesicle population expanded. In contrast to that, increasing the stimulus frequency reduced the relative size of the population of alkaline vesicles. Measurement of the time constant for reacification and calculation of the time constant for endocytosis revealed that both time constants were variable with regard to the stimulus condition. Furthermore, we show that the dynamics of the alkaline vesicle population can be predicted by a simple mathematical model. In conclusion, here a novel methodical approach to analyze dynamic properties of alkaline vesicles is presented and validated as a convenient method for the detection of intracellular events. Using this method we show that the population of alkaline vesicles is highly dynamic and depends both on stimulus strength and frequency. Our results implicate that determination of the alkaline vesicle population size may provide new insights into the kinetics of endocytic retrieval. PMID:25079223

Climate Effects and Feedback Structure Determining Weed Population Dynamics in a Long-Term Experiment

PubMed Central

Lima, Mauricio; Navarrete, Luis; González-Andujar, José Luis

2012-01-01

Pest control is one of the areas in which population dynamic theory has been successfully applied to solve practical problems. However, the links between population dynamic theory and model construction have been less emphasized in the management and control of weed populations. Most management models of weed population dynamics have emphasized the role of the endogenous process, but the role of exogenous variables such as climate have been ignored in the study of weed populations and their management. Here, we use long-term data (22 years) on two annual weed species from a locality in Central Spain to determine the importance of endogenous and exogenous processes (local and large-scale climate factors). Our modeling study determined two different feedback structures and climate effects in the two weed species analyzed. While Descurainia sophia exhibited a second-order feedback and low climate influence, Veronica hederifolia was characterized by a first-order feedback structure and important effects from temperature and rainfall. Our results strongly suggest the importance of theoretical population dynamics in understanding plant population systems. Moreover, the use of this approach, discerning between the effect of exogenous and endogenous factors, can be fundamental to applying weed management practices in agricultural systems and to controlling invasive weedy species. This is a radical change from most approaches currently used to guide weed and invasive weedy species managements. PMID:22272362

How Resource Phenology Affects Consumer Population Dynamics.

PubMed

Bewick, Sharon; Cantrell, R Stephen; Cosner, Chris; Fagan, William F

2016-02-01

Climate change drives uneven phenology shifts across taxa, and this can result in changes to the phenological match between interacting species. Shifts in the relative phenology of partner species are well documented, but few studies have addressed the effects of such changes on population dynamics. To explore this, we develop a phenologically explicit model describing consumer-resource interactions. Focusing on scenarios for univoltine insects, we show how changes in resource phenology can be reinterpreted as transformations in the year-to-year recursion relationships defining consumer population dynamics. This perspective provides a straightforward path for interpreting the long-term population consequences of phenology change. Specifically, by relating the outcome of phenological shifts to species traits governing recursion relationships (e.g., consumer fecundity or competitive scenario), we demonstrate how changes in relative phenology can force systems into different dynamical regimes, with major implications for resource management, conservation, and other areas of applied dynamics.

Genetic diversity affects the strength of population regulation in a marine fish.

PubMed

Johnson, D W; Freiwald, J; Bernardi, G

2016-03-01

Variation is an essential feature of biological populations, yet much of ecological theory treats individuals as though they are identical. This simplifying assumption is often justified by the perception that variation among individuals does not have significant effects on the dynamics of whole populations. However, this perception may be skewed by a historic focus on studying single populations. A true evaluation of the extent to which among-individual variation affects the dynamics of populations requires the study of multiple populations. In this study, we examined variation in the dynamics of populations of a live-bearing, marine fish (black surfperch; Embiotoca jacksoni). In collaboration with an organization of citizen scientists (Reef Check California), we were able to examine the dynamics of eight populations that were distributed throughout approximately 700 km of coastline, a distance that encompasses much of this species' range. We hypothesized that genetic variation within a local population would be related to the intensity of competition and to the strength of population regulation. To test this hypothesis, we examined whether genetic diversity (measured by the diversity of mitochondrial DNA haplotypes) was related to the strength of population regulation. Low-diversity populations experienced strong density dependence in population growth rates and population sizes were regulated much more tightly than they were in high-diversity populations. Mechanisms that contributed to this pattern include links between genetic diversity, habitat use, and spatial crowding. On average, low-diversity populations used less of the available habitat and exhibited greater spatial clustering (and more intense competition) for a given level of density (measured at the scale of the reef). Although the populations we studied also varied with respect to exogenous characteristics (habitat complexity, densities of predators, and interspecific competitors), none of these characteristics was significantly related to the strength of population regulation. In contrast, an endogenous characteristic of the population (genetic diversity) explained 77% of the variation in the strength of population regulation (95% CI: 27-94%). Our results suggest that the genetic and phenotypic composition of populations can play a major role in their dynamics.

The Influence of Individual Variability on Zooplankton Population Dynamics under Different Environmental Conditions

NASA Astrophysics Data System (ADS)

Bi, R.; Liu, H.

2016-02-01

Understanding how biological components respond to environmental changes could be insightful to predict ecosystem trajectories under different climate scenarios. Zooplankton are key components of marine ecosystems and changes in their dynamics could have major impact on ecosystem structure. We developed an individual-based model of a common coastal calanoid copepod Acartia tonsa to examine how environmental factors affect zooplankton population dynamics and explore the role of individual variability in sustaining population under various environmental conditions consisting of temperature, food concentration and salinity. Total abundance, egg production and proportion of survival were used to measure population success. Results suggested population benefits from high level of individual variability under extreme environmental conditions including unfavorable temperature, salinity, as well as low food concentration, and selection on fast-growers becomes stronger with increasing individual variability and increasing environmental stress. Multiple regression analysis showed that temperature, food concentration, salinity and individual variability have significant effects on survival of A. tonsa population. These results suggest that environmental factors have great influence on zooplankton population, and individual variability has important implications for population survivability under unfavorable conditions. Given that marine ecosystems are at risk from drastic environmental changes, understanding how individual variability sustains populations could increase our capability to predict population dynamics in a changing environment.

POPULATION DYNAMICS OF AMBIENT AND ALTERED EARTHWORM COMMUNITIES IN ROW-CROP AGROECOSYSTEMS IN OHIO, USA

EPA Science Inventory

Although earthworms are known to influence agroecosystem processes, there are relatively few long-term studies addressing population dynamics under cropping systems in which earthworm populations were intentionally altered. We assessed earthworm communities from fall 1994 to spr...

Fundamental population-productivity relationships can be modified through density-dependent feedbacks of life-history evolution.

PubMed

Kuparinen, Anna; Stenseth, Nils Christian; Hutchings, Jeffrey A

2014-12-01

The evolution of life histories over contemporary time scales will almost certainly affect population demography. One important pathway for such eco-evolutionary interactions is the density-dependent regulation of population dynamics. Here, we investigate how fisheries-induced evolution (FIE) might alter density-dependent population-productivity relationships. To this end, we simulate the eco-evolutionary dynamics of an Atlantic cod (Gadus morhua) population under fishing, followed by a period of recovery in the absence of fishing. FIE is associated with increases in juvenile production, the ratio of juveniles to mature population biomass, and the ratio of the mature population biomass relative to the total population biomass. In contrast, net reproductive rate (R 0 ) and per capita population growth rate (r) decline concomitantly with evolution. Our findings suggest that FIE can substantially modify the fundamental population-productivity relationships that underlie density-dependent population regulation and that form the primary population-dynamical basis for fisheries stock-assessment projections. From a conservation and fisheries-rebuilding perspective, we find that FIE reduces R 0 and r, the two fundamental correlates of population recovery ability and inversely extinction probability.

Animal population dynamics: Identification of critical components

USGS Publications Warehouse

Emlen, J.M.; Pikitch, E.K.

1989-01-01

There is a growing interest in the use of population dynamics models in environmental risk assessment and the promulgation of environmental regulatory policies. Unfortunately, because of species and areal differences in the physical and biotic influences on population dynamics, such models must almost inevitably be both complex and species- or site-specific. Given the emormous variety of species and sites of potential concern, this fact presents a problem; it simply is not possible to construct models for all species and circumstances. Therefore, it is useful, before building predictive population models, to discover what input parameters are of critical importance to the desired output. This information should enable the construction of simpler and more generalizable models. As a first step, it is useful to consider population models as composed to two, partly separable classes, one comprising the purely mechanical descriptors of dynamics from given demographic parameter values, and the other describing the modulation of the demographic parameters by environmental factors (changes in physical environment, species interactions, pathogens, xenobiotic chemicals). This division permits sensitivity analyses to be run on the first of these classes, providing guidance for subsequent model simplification. We here apply such a sensitivity analysis to network models of mammalian and avian population dynamics.

Climatic and density influences on recruitment in an irruptive population of Roosevelt elk

USGS Publications Warehouse

Starns, Heath D.; Ricca, Mark A.; Duarte, Adam; Weckerly, Floyd W.

2014-01-01

Current paradigms of ungulate population ecology recognize that density-dependent and independent mechanisms are not always mutually exclusive. Long-term data sets are necessary to assess the relative strength of each mechanism, especially when populations display irruptive dynamics. Using an 18-year time series of population abundances of Roosevelt elk (Cervus elaphus roosevelti) inhabiting Redwood National Park in northwestern California we assessed the influence of population size and climatic variation on elk recruitment and whether irruptive dynamics occurred. An information-theoretic model selection analysis indicated that abundance lagged 2 years and neither climatic factors nor a mix of abundance and climatic factors influenced elk recruitment. However, density-dependent recruitment differed between when the population was declining and when the population increased and then stabilized at an abundance lower than at the start of the decline. The population displayed irruptive dynamics.

Unusual dynamics of extinction in a simple ecological model.

PubMed Central

Sinha, S; Parthasarathy, S

1996-01-01

Studies on natural populations and harvesting biological resources have led to the view, commonly held, that (i) populations exhibiting chaotic oscillations run a high risk of extinction; and (ii) a decrease in emigration/exploitation may reduce the risk of extinction. Here we describe a simple ecological model with emigration/depletion that shows behavior in contrast to this. This model displays unusual dynamics of extinction and survival, where populations growing beyond a critical rate can persist within a band of high depletion rates, whereas extinction occurs for lower depletion rates. Though prior to extinction at lower depletion rates the population exhibits chaotic dynamics with large amplitudes of variation and very low minima, at higher depletion rates the population persists at chaos but with reduced variation and increased minima. For still higher values, within the band of persistence, the dynamics show period reversal leading to stability. These results illustrate that chaos does not necessarily lead to population extinction. In addition, the persistence of populations at high depletion rates has important implications in the considerations of strategies for the management of biological resources. PMID:8643661

Chronic radiation exposure modifies temporal dynamics of cytogenetic but not reproductive indicators in Scots pine populations.

PubMed

Geras'kin, Stanislav; Oudalova, Alla; Kuzmenkov, Alexey; Vasiliyev, Denis

2018-04-18

Over a period of 13 years (2003-2015), reproductive and cytogenetic effects are investigated in Scots pine populations growing in the Bryansk region of Russia radioactively contaminated as a result of the Chernobyl accident. In reference populations, the frequencies of cytogenetic abnormalities are shown to change with time in a cyclic manner. In chronically exposed populations, the cyclic patterns in temporal dynamics of cytogenetic abnormalities appear to be disturbed. In addition, a tendency to decrease in the frequencies of cytogenetic abnormalities with time as well as an increase in their variability with dose rate is revealed. In contrast, no significant impact of chronic radiation exposure on the time dynamics of reproductive indexes is detected. Finally, long-term observations on chronically exposed Scots pine populations revealed qualitative differences in the temporal dynamics of reproductive and cytogenetic indicators. Copyright © 2018 Elsevier Ltd. All rights reserved.

Coupling population dynamics with earth system models: the POPEM model.

PubMed

Navarro, Andrés; Moreno, Raúl; Jiménez-Alcázar, Alfonso; Tapiador, Francisco J

2017-09-16

Precise modeling of CO 2 emissions is important for environmental research. This paper presents a new model of human population dynamics that can be embedded into ESMs (Earth System Models) to improve climate modeling. Through a system dynamics approach, we develop a cohort-component model that successfully simulates historical population dynamics with fine spatial resolution (about 1°×1°). The population projections are used to improve the estimates of CO 2 emissions, thus transcending the bulk approach of existing models and allowing more realistic non-linear effects to feature in the simulations. The module, dubbed POPEM (from Population Parameterization for Earth Models), is compared with current emission inventories and validated against UN aggregated data. Finally, it is shown that the module can be used to advance toward fully coupling the social and natural components of the Earth system, an emerging research path for environmental science and pollution research.

A juvenile-adult population model: climate change, cannibalism, reproductive synchrony, and strong Allee effects.

PubMed

Veprauskas, Amy; Cushing, J M

2017-03-01

We study a discrete time, structured population dynamic model that is motivated by recent field observations concerning certain life history strategies of colonial-nesting gulls, specifically the glaucous-winged gull (Larus glaucescens). The model focuses on mechanisms hypothesized to play key roles in a population's response to degraded environment resources, namely, increased cannibalism and adjustments in reproductive timing. We explore the dynamic consequences of these mechanics using a juvenile-adult structure model. Mathematically, the model is unusual in that it involves a high co-dimension bifurcation at [Formula: see text] which, in turn, leads to a dynamic dichotomy between equilibrium states and synchronized oscillatory states. We give diagnostic criteria that determine which dynamic is stable. We also explore strong Allee effects caused by positive feedback mechanisms in the model and the possible consequence that a cannibalistic population can survive when a non-cannibalistic population cannot.

Connecting micro dynamics and population distributions in system dynamics models

PubMed Central

Rahmandad, Hazhir; Chen, Hsin-Jen; Xue, Hong; Wang, Youfa

2014-01-01

Researchers use system dynamics models to capture the mean behavior of groups of indistinguishable population elements (e.g., people) aggregated in stock variables. Yet, many modeling problems require capturing the heterogeneity across elements with respect to some attribute(s) (e.g., body weight). This paper presents a new method to connect the micro-level dynamics associated with elements in a population with the macro-level population distribution along an attribute of interest without the need to explicitly model every element. We apply the proposed method to model the distribution of Body Mass Index and its changes over time in a sample population of American women obtained from the U.S. National Health and Nutrition Examination Survey. Comparing the results with those obtained from an individual-based model that captures the same phenomena shows that our proposed method delivers accurate results with less computation than the individual-based model. PMID:25620842

Coping with changing northern environments: the role of the stress axis in birds and mammals.

PubMed

Boonstra, Rudy

2004-04-01

Northern environments present ecological and physiological problems for homeotherms that require adaptations to cope with severe and less predictable physical factors while at the same time continuing to have to cope with the biological ones, such as competition and predation. The stress axis plays a central role in these adaptations and I discuss the range of solutions that birds and mammals have evolved. The stress response in these animals is not static when a challenge occurs, but may be modulated depending on the biological function during the annual cycle (breeding versus nonbreeding), either under-responding to permit reproduction (some song birds) or responding vigorously, yet not having this compromise reproduction (Arctic ground squirrels). Both may trade off survival for reproduction. In contrast, the snowshoe hare shows the expected stress response to chronic high predation risk over 2-3 years: body resources are geared to survival and reproduction is inhibited. Two long term, persistent, and pervasive changes will confront northern birds and mammals in the 21(st) century: global change and persistent organochlorine pollutants (POPs). These may result in either adaptations or shifts in distribution and abundance. For the former, latitudinal variation in the stress axis may help song birds respond rapidly; population variation in the stress axis response is unknown in northern mammals and relatively sedentary mammals may be unable to shift their distribution rapidly to adjust major climate shifts. For the latter, the few POPs studies that have examined the stress axis indicate marked negative effects.

Dynamics of climate-based malaria transmission model with age-structured human population

NASA Astrophysics Data System (ADS)

Addawe, Joel; Pajimola, Aprimelle Kris

2016-10-01

In this paper, we proposed to study the dynamics of malaria transmission with periodic birth rate of the vector and an age-structure for the human population. The human population is divided into two compartments: pre-school (0-5 years) and the rest of the human population. We showed the existence of a disease-free equilibrium point. Using published epidemiological parameters, we use numerical simulations to show potential effect of climate change in the dynamics of age-structured malaria transmission. Numerical simulations suggest that there exists an asymptotically attractive solution that is positive and periodic.

Evolution of the stellar mass function in multiple-population globular clusters

NASA Astrophysics Data System (ADS)

Vesperini, Enrico; Hong, Jongsuk; Webb, Jeremy J.; D'Antona, Franca; D'Ercole, Annibale

2018-05-01

We present the results of a survey of N-body simulations aimed at studying the effects of the long-term dynamical evolution on the stellar mass function (MF) of multiple stellar populations in globular clusters. Our simulations show that if first-(1G) and second-generation (2G) stars have the same initial MF (IMF), the global MFs of the two populations are affected similarly by dynamical evolution and no significant differences between the 1G and 2G MFs arise during the cluster's evolution. If the two populations have different IMFs, dynamical effects do not completely erase memory of the initial differences. Should observations find differences between the global 1G and 2G MFs, these would reveal the fingerprints of differences in their IMFs. Irrespective of whether the 1G and 2G populations have the same global IMF or not, dynamical effects can produce differences between the local (measured at various distances from the cluster centre) 1G and 2G MFs; these differences are a manifestation of the process of mass segregation in populations with different initial structural properties. In dynamically old and spatially mixed clusters, however, differences between the local 1G and 2G MFs can reveal differences between the 1G and 2G global MFs. In general, for clusters with any dynamical age, large differences between the local 1G and 2G MFs are more likely to be associated with differences in the global MF. Our study also reveals a dependence of the spatial mixing rate on the stellar mass, another dynamical consequence of the multiscale nature of multiple-population clusters.

Integrating host, natural enemy, and other processes in population models of the pine sawfly

Treesearch

A. A. Sharov

1991-01-01

Explanation of population dynamics is one of the main problems in population ecology. There are two main approaches to the explanation: the factor approach and the dynamic approach. According to the first, an explanation is obtained when the effect of various environmental factors on population density is revealed. Such analysis is performed using well developed...

Effects of temporal variation in temperature and density dependence on insect population dynamics

USDA-ARS?s Scientific Manuscript database

Understanding effects of environmental variation on insect populations is important in light of predictions about increasing future climatic variability. In order to understand the effects of changing environmental variation on population dynamics and life history evolution in insects one would need...

Evaluating Effects of Localized Habitat Manipulations on Landscape-level Dynamics of White-footed Mouse Populations

EPA Science Inventory

Due to complex population dynamics and migration behaviors, the well-being of animal populations that host human diseases sometimes varies across landscapes in ways that cannot be deduced from geographic abundance patterns alone. In such cases, efficient management of ecological...

Evolution of Fitness in Experimental Populations of Vesicular Stomatitis Virus

PubMed Central

Elena, S. F.; Gonzalez-Candelas, F.; Novella, I. S.; Duarte, E. A.; Clarke, D. K.; Domingo, E.; Holland, J. J.; Moya, A.

1996-01-01

The evolution of fitness in experimental clonal populations of vesicular stomatitis virus (VSV) has been compared under different genetic (fitness of initial clone) and demographic (population dynamics) regimes. In spite of the high genetic heterogeneity among replicates within experiments, there is a clear effect of population dynamics on the evolution of fitness. Those populations that went through strong periodic bottlenecks showed a decreased fitness in competition experiments with wild type. Conversely, mutant populations that were transferred under the dynamics of continuous population expansions increased their fitness when compared with the same wild type. The magnitude of the observed effect depended on the fitness of the original viral clone. Thus, high fitness clones showed a larger reduction in fitness than low fitness clones under dynamics with included periodic bottleneck. In contrast, the gain in fitness was larger the lower the initial fitness of the viral clone. The quantitative genetic analysis of the trait ``fitness'' in the resulting populations shows that genetic variation for the trait is positively correlated with the magnitude of the change in the same trait. The results are interpreted in terms of the operation of MULLER's ratchet and genetic drift as opposed to the appearance of beneficial mutations. PMID:8849878

Generating a Dynamic Synthetic Population – Using an Age-Structured Two-Sex Model for Household Dynamics

PubMed Central

Namazi-Rad, Mohammad-Reza; Mokhtarian, Payam; Perez, Pascal

2014-01-01

Generating a reliable computer-simulated synthetic population is necessary for knowledge processing and decision-making analysis in agent-based systems in order to measure, interpret and describe each target area and the human activity patterns within it. In this paper, both synthetic reconstruction (SR) and combinatorial optimisation (CO) techniques are discussed for generating a reliable synthetic population for a certain geographic region (in Australia) using aggregated- and disaggregated-level information available for such an area. A CO algorithm using the quadratic function of population estimators is presented in this paper in order to generate a synthetic population while considering a two-fold nested structure for the individuals and households within the target areas. The baseline population in this study is generated from the confidentialised unit record files (CURFs) and 2006 Australian census tables. The dynamics of the created population is then projected over five years using a dynamic micro-simulation model for individual- and household-level demographic transitions. This projection is then compared with the 2011 Australian census. A prediction interval is provided for the population estimates obtained by the bootstrapping method, by which the variability structure of a predictor can be replicated in a bootstrap distribution. PMID:24733522

FITPOP, a heuristic simulation model of population dynamics and genetics with special reference to fisheries

USGS Publications Warehouse

McKenna, James E.

2000-01-01

Although, perceiving genetic differences and their effects on fish population dynamics is difficult, simulation models offer a means to explore and illustrate these effects. I partitioned the intrinsic rate of increase parameter of a simple logistic-competition model into three components, allowing specification of effects of relative differences in fitness and mortality, as well as finite rate of increase. This model was placed into an interactive, stochastic environment to allow easy manipulation of model parameters (FITPOP). Simulation results illustrated the effects of subtle differences in genetic and population parameters on total population size, overall fitness, and sensitivity of the system to variability. Several consequences of mixing genetically distinct populations were illustrated. For example, behaviors such as depression of population size after initial introgression and extirpation of native stocks due to continuous stocking of genetically inferior fish were reproduced. It also was shown that carrying capacity relative to the amount of stocking had an important influence on population dynamics. Uncertainty associated with parameter estimates reduced confidence in model projections. The FITPOP model provided a simple tool to explore population dynamics, which may assist in formulating management strategies and identifying research needs.

Populational Growth Models Proportional to Beta Densities with Allee Effect

NASA Astrophysics Data System (ADS)

Aleixo, Sandra M.; Rocha, J. Leonel; Pestana, Dinis D.

2009-05-01

We consider populations growth models with Allee effect, proportional to beta densities with shape parameters p and 2, where the dynamical complexity is related with the Malthusian parameter r. For p>2, these models exhibit a population dynamics with natural Allee effect. However, in the case of 1

Human population dynamics in Europe over the Last Glacial Maximum.

PubMed

Tallavaara, Miikka; Luoto, Miska; Korhonen, Natalia; Järvinen, Heikki; Seppä, Heikki

2015-07-07

The severe cooling and the expansion of the ice sheets during the Last Glacial Maximum (LGM), 27,000-19,000 y ago (27-19 ky ago) had a major impact on plant and animal populations, including humans. Changes in human population size and range have affected our genetic evolution, and recent modeling efforts have reaffirmed the importance of population dynamics in cultural and linguistic evolution, as well. However, in the absence of historical records, estimating past population levels has remained difficult. Here we show that it is possible to model spatially explicit human population dynamics from the pre-LGM at 30 ky ago through the LGM to the Late Glacial in Europe by using climate envelope modeling tools and modern ethnographic datasets to construct a population calibration model. The simulated range and size of the human population correspond significantly with spatiotemporal patterns in the archaeological data, suggesting that climate was a major driver of population dynamics 30-13 ky ago. The simulated population size declined from about 330,000 people at 30 ky ago to a minimum of 130,000 people at 23 ky ago. The Late Glacial population growth was fastest during Greenland interstadial 1, and by 13 ky ago, there were almost 410,000 people in Europe. Even during the coldest part of the LGM, the climatically suitable area for human habitation remained unfragmented and covered 36% of Europe.

Human population dynamics in Europe over the Last Glacial Maximum

PubMed Central

Tallavaara, Miikka; Luoto, Miska; Korhonen, Natalia; Järvinen, Heikki; Seppä, Heikki

2015-01-01

The severe cooling and the expansion of the ice sheets during the Last Glacial Maximum (LGM), 27,000–19,000 y ago (27–19 ky ago) had a major impact on plant and animal populations, including humans. Changes in human population size and range have affected our genetic evolution, and recent modeling efforts have reaffirmed the importance of population dynamics in cultural and linguistic evolution, as well. However, in the absence of historical records, estimating past population levels has remained difficult. Here we show that it is possible to model spatially explicit human population dynamics from the pre-LGM at 30 ky ago through the LGM to the Late Glacial in Europe by using climate envelope modeling tools and modern ethnographic datasets to construct a population calibration model. The simulated range and size of the human population correspond significantly with spatiotemporal patterns in the archaeological data, suggesting that climate was a major driver of population dynamics 30–13 ky ago. The simulated population size declined from about 330,000 people at 30 ky ago to a minimum of 130,000 people at 23 ky ago. The Late Glacial population growth was fastest during Greenland interstadial 1, and by 13 ky ago, there were almost 410,000 people in Europe. Even during the coldest part of the LGM, the climatically suitable area for human habitation remained unfragmented and covered 36% of Europe. PMID:26100880

Integral control for population management.

PubMed

Guiver, Chris; Logemann, Hartmut; Rebarber, Richard; Bill, Adam; Tenhumberg, Brigitte; Hodgson, Dave; Townley, Stuart

2015-04-01

We present a novel management methodology for restocking a declining population. The strategy uses integral control, a concept ubiquitous in control theory which has not been applied to population dynamics. Integral control is based on dynamic feedback-using measurements of the population to inform management strategies and is robust to model uncertainty, an important consideration for ecological models. We demonstrate from first principles why such an approach to population management is suitable via theory and examples.

Enhanced/synthetic vision and head-worn display technologies for terminal maneuvering area NextGen operations

NASA Astrophysics Data System (ADS)

Arthur, Jarvis J., III; Prinzel, Lawrence J., III; Williams, Steven P.; Bailey, Randall E.; Shelton, Kevin J.; Norman, R. Mike

2011-06-01

NASA is researching innovative technologies for the Next Generation Air Transportation System (NextGen) to provide a "Better-Than-Visual" (BTV) capability as adjunct to "Equivalent Visual Operations" (EVO); that is, airport throughputs equivalent to that normally achieved during Visual Flight Rules (VFR) operations rates with equivalent and better safety in all weather and visibility conditions including Instrument Meteorological Conditions (IMC). These new technologies build on proven flight deck systems and leverage synthetic and enhanced vision systems. Two piloted simulation studies were conducted to access the use of a Head-Worn Display (HWD) with head tracking for synthetic and enhanced vision systems concepts. The first experiment evaluated the use a HWD for equivalent visual operations to San Francisco International Airport (airport identifier: KSFO) compared to a visual concept and a head-down display concept. A second experiment evaluated symbology variations under different visibility conditions using a HWD during taxi operations at Chicago O'Hare airport (airport identifier: KORD). Two experiments were conducted, one in a simulated San Francisco airport (KSFO) approach operation and the other, in simulated Chicago O'Hare surface operations, evaluating enhanced/synthetic vision and head-worn display technologies for NextGen operations. While flying a closely-spaced parallel approach to KSFO, pilots rated the HWD, under low-visibility conditions, equivalent to the out-the-window condition, under unlimited visibility, in terms of situational awareness (SA) and mental workload compared to a head-down enhanced vision system. There were no differences between the 3 display concepts in terms of traffic spacing and distance and the pilot decision-making to land or go-around. For the KORD experiment, the visibility condition was not a factor in pilot's rating of clutter effects from symbology. Several concepts for enhanced implementations of an unlimited field-of-regard BTV concept for low-visibility surface operations were determined to be equivalent in pilot ratings of efficacy and usability.

Sea Hare Aplysia punctata (Mollusca: Gastropoda) Can Maintain Shell Calcification under Extreme Ocean Acidification.

PubMed

Carey, Nicholas; Dupont, Sam; Sigwart, Julia D

2016-10-01

Ocean acidification is expected to cause energetic constraints upon marine calcifying organisms such as molluscs and echinoderms, because of the increased costs of building or maintaining shell material in lower pH. We examined metabolic rate, shell morphometry, and calcification in the sea hare Aplysia punctata under short-term exposure (19 days) to an extreme ocean acidification scenario (pH 7.3, ∼2800 μatm pCO 2 ), along with a group held in control conditions (pH 8.1, ∼344 μatm pCO 2 ). This gastropod and its congeners are broadly distributed and locally abundant grazers, and have an internal shell that protects the internal organs. Specimens were examined for metabolic rate via closed-chamber respirometry, followed by removal and examination of the shell under confocal microscopy. Staining using calcein determined the amount of new calcification that occurred over 6 days at the end of the acclimation period. The width of new, pre-calcified shell on the distal shell margin was also quantified as a proxy for overall shell growth. Aplysia punctata showed a 30% reduction in metabolic rate under low pH, but calcification was not affected. This species is apparently able to maintain calcification rate even under extreme low pH, and even when under the energetic constraints of lower metabolism. This finding adds to the evidence that calcification is a largely autonomous process of crystallization that occurs as long as suitable haeomocoel conditions are preserved. There was, however, evidence that the accretion of new, noncalcified shell material may have been reduced, which would lead to overall reduced shell growth under longer-term exposures to low pH independent of calcification. Our findings highlight that the chief impact of ocean acidification upon the ability of marine invertebrates to maintain their shell under low pH may be energetic constraints that hinder growth of supporting structure, rather than maintenance of calcification.

Assessment of doses to game animals in Finland.

PubMed

Vetikko, Virve; Kostiainen, Eila

2013-11-01

A study was carried out to assess the dose rates to game animals in Finland affected by the radioactive caesium deposition that occurred after the accident at the Chernobyl nuclear power plant in Ukraine in 1986. The aim of this assessment was to obtain new information on the dose rates to mammals and birds under Finnish conditions. Dose rates were calculated using the ERICA Assessment Tool developed within the EC 6th Framework Programme. The input data consisted of measured activity concentrations of (137)Cs and (134)Cs in soil and lake water samples and in flesh samples of selected animal species obtained for environmental monitoring. The study sites were located in the municipality of Lammi, Southern Finland, where the average (137)Cs deposition was 46.5 kBq m(-2) (1 October 1987). The study sites represented the areas receiving the highest deposition in Finland after the Chernobyl accident. The selected species included moose (Alces alces), arctic hare (Lepus timidus) and several bird species: black grouse (Tetrao tetrix), hazel hen (Bonasia bonasia), mallard (Anas platurhynchos), goldeneye (Bucephala clangula) and teal (Anas crecca). For moose, dose rates were calculated for the years 1986-1990 and for the 2000s. For all other species, maximal measured activity concentrations were used. The results showed that the dose rates to these species did not exceed the default screening level of 10 μGy h(-1) used as a protection criterion. The highest total dose rate (internal and external summed), 3.7 μGy h(-1), was observed for the arctic hare in 1986. Although the dose rate of 3.7 μGy h(-1) cannot be considered negligible given the uncertainties involved in predicting the dose rates, the possible harmful effects related to this dose rate are too small to be assessed based on current knowledge on the biological effects of low doses in mammals. Copyright © 2013 Elsevier Ltd. All rights reserved.

Enhanced/Synthetic Vision and Head-Worn Display Technologies for Terminal Maneuvering Area NextGen Operations

NASA Technical Reports Server (NTRS)

Arthur, Jarvis J., III; Prinzell, Lawrence J.; Williams, Steven P.; Bailey, Randall E.; Shelton, Kevin J.; Norman, R. Mike

2011-01-01

NASA is researching innovative technologies for the Next Generation Air Transportation System (NextGen) to provide a "Better-Than-Visual" (BTV) capability as adjunct to "Equivalent Visual Operations" (EVO); that is, airport throughputs equivalent to that normally achieved during Visual Flight Rules (VFR) operations rates with equivalent and better safety in all weather and visibility conditions including Instrument Meteorological Conditions (IMC). These new technologies build on proven flight deck systems and leverage synthetic and enhanced vision systems. Two piloted simulation studies were conducted to access the use of a Head-Worn Display (HWD) with head tracking for synthetic and enhanced vision systems concepts. The first experiment evaluated the use a HWD for equivalent visual operations to San Francisco International Airport (airport identifier: KSFO) compared to a visual concept and a head-down display concept. A second experiment evaluated symbology variations under different visibility conditions using a HWD during taxi operations at Chicago O'Hare airport (airport identifier: KORD). Two experiments were conducted, one in a simulated San Francisco airport (KSFO) approach operation and the other, in simulated Chicago O'Hare surface operations, evaluating enhanced/synthetic vision and head-worn display technologies for NextGen operations. While flying a closely-spaced parallel approach to KSFO, pilots rated the HWD, under low-visibility conditions, equivalent to the out-the-window condition, under unlimited visibility, in terms of situational awareness (SA) and mental workload compared to a head-down enhanced vision system. There were no differences between the 3 display concepts in terms of traffic spacing and distance and the pilot decision-making to land or go-around. For the KORD experiment, the visibility condition was not a factor in pilot's rating of clutter effects from symbology. Several concepts for enhanced implementations of an unlimited field-of-regard BTV concept for low-visibility surface operations were determined to be equivalent in pilot ratings of efficacy and usability.

Radius Determination of Solar-type Stars Using Asteroseismology: What to Expect from the Kepler Mission

NASA Astrophysics Data System (ADS)

Stello, Dennis; Chaplin, William J.; Bruntt, Hans; Creevey, Orlagh L.; García-Hernández, Antonio; Monteiro, Mario J. P. F. G.; Moya, Andrés; Quirion, Pierre-Olivier; Sousa, Sergio G.; Suárez, Juan-Carlos; Appourchaux, Thierry; Arentoft, Torben; Ballot, Jerome; Bedding, Timothy R.; Christensen-Dalsgaard, Jørgen; Elsworth, Yvonne; Fletcher, Stephen T.; García, Rafael A.; Houdek, Günter; Jiménez-Reyes, Sebastian J.; Kjeldsen, Hans; New, Roger; Régulo, Clara; Salabert, David; Toutain, Thierry

2009-08-01

For distant stars, as observed by the NASA Kepler satellite, parallax information is currently of fairly low quality and is not complete. This limits the precision with which the absolute sizes of the stars and their potential transiting planets can be determined by traditional methods. Asteroseismology will be used to aid the radius determination of stars observed during NASA's Kepler mission. We report on the recent asteroFLAG hare-and-hounds Exercise#2, where a group of "hares" simulated data of F-K main-sequence stars that a group of "hounds" sought to analyze, aimed at determining the stellar radii. We investigated stars in the range 9 < V < 15, both with and without parallaxes. We further test different uncertainties in T eff, and compare results with and without using asteroseismic constraints. Based on the asteroseismic large frequency spacing, obtained from simulations of 4 yr time series data from the Kepler mission, we demonstrate that the stellar radii can be correctly and precisely determined, when combined with traditional stellar parameters from the Kepler Input Catalogue. The radii found by the various methods used by each independent hound generally agree with the true values of the artificial stars to within 3%, when the large frequency spacing is used. This is 5-10 times better than the results where seismology is not applied. These results give strong confidence that radius estimation can be performed to better than 3% for solar-like stars using automatic pipeline reduction. Even when the stellar distance and luminosity are unknown we can obtain the same level of agreement. Given the uncertainties used for this exercise we find that the input log g and parallax do not help to constrain the radius, and that T eff and metallicity are the only parameters we need in addition to the large frequency spacing. It is the uncertainty in the metallicity that dominates the uncertainty in the radius.