Modelo discreto para o ciclo eritrocitário da Malária

In this work, some aspects of the erythrocyte cycle of the malaria parasite was incorporated into a cellular automata model to simulated the major factors leading to disruption of the erythrocyte cycle and consequent appearance of gametocytes, which infected the mosquitoes. Furthermore, the time seies of parasitaemia of infected patients was analyzed and compared to simulated data. The results suggested that differences in the temporal patterns of the asexual parasitaemia are associated with different effectiveness of the immune system in controlling the infection

Cetaceans of Southeast Alaska: Distribution and Seasonal Occurrence

Aim To assess the distribution, group size, seasonal occurrence and annual trends of cetaceans. Location The study area included all major inland waters of Southeast Alaska. Methods Between 1991 and 2007, cetacean surveys were conducted by observers who kept a constant watch when the vessel was underway and recorded all cetaceans encountered. For each species, we examined distributional patterns, group size, seasonal occurrence and annual trends. Analysis of variance (anova F) was used to test for differences in group sizes between multiple means, and Student’s t-test was used to detect differences between pairwise means. Cetacean seasonal occurrence and annual trends were investigated using a generalized linear model framework. Results Humpback whales (Megaptera novaeangliae) were seen throughout the region, with numbers lowest in spring and highest in the fall. Fin whale (Balaenoptera physalus) and minke whale (Balaenoptera acutorostrata) distributions were more restricted than that reported for humpback whales, and the low number of sightings precluded evaluating seasonal trends. Three killer whale (Orcinus orca) eco-types were documented with distributions occurring throughout inland waters. Seasonal patterns were not detected or could not be evaluated for resident and offshore killer whales, respectively; however, the transient eco-type was more abundant in the summer. Dall’s porpoise (Phocoenoides dalli) were distributed throughout the region, with more sightings in spring and summer than in fall. Harbour porpoise (Phocoena phocoena) distribution was clumped, with concentrations occurring in the Icy Strait/Glacier Bay and Wrangell areas and with no evidence of seasonality. Pacific white-sided dolphins (Lagenorhynchus obliquidens) were observed only occasionally, with more sightings in the spring. For most species, group size varied on both an annual and seasonal basis. Main conclusions Seven cetacean species occupy the inland waters of Southeast Alaska, with distribution, group size, seasonal occurrence and annual trends varying by species. Future studies that compare spatial and temporal patterns with other features (e.g. oceanography, prey resources) may help in identifying the key factors that support the high density and biodiversity of cetaceans found in this region. An increased understanding of the region’s marine ecology is an essential step towards ensuring the long-term conservation of cetaceans in Southeast Alaska.

Killer Whales and Marine Mammal Trends in The North Pacific—A Re-Examination of Evidence for Sequential Megafauna Collapse and the Prey-Switching Hypothesis

Springer et al. (2003) contend that sequential declines occurred in North Pacific populations of harbor and fur seals, Steller sea lions, and sea otters. They hypothesize that these were due to increased predation by killer whales, when industrial whaling’s removal of large whales as a supposed primary food source precipitated a prey switch. Using a regional approach, we reexamined whale catch data, killer whale predation observations, and the current biomass and trends of potential prey, and found little support for the prey-switching hypothesis. Large whale biomass in the Bering Sea did not decline as much as suggested by Springer et al., and much of the reduction occurred 50–100 yr ago, well before the declines of pinnipeds and sea otters began; thus, the need to switch prey starting in the 1970s is doubtful. With the sole exception that the sea otter decline followed the decline of pinnipeds, the reported declines were not in fact sequential. Given this, it is unlikely that a sequential megafaunal collapse from whales to sea otters occurred. The spatial and temporal patterns of pinniped and sea otter population trends are more complex than Springer et al. suggest, and are often inconsistent with their hypothesis. Populations remained stable or increased in many areas, despite extensive historical whaling and high killer whale abundance. Furthermore, observed killer whale predation has largely involved pinnipeds and small cetaceans; there is little evidence that large whales were ever a major prey item in high latitudes. Small cetaceans (ignored by Springer et al.) were likely abundant throughout the period. Overall, we suggest that the Springer et al. hypothesis represents a misleading and simplistic view of events and trophic relationships within this complex marine ecosystem.

The trophic role of the squid Loligo plei as a keystone species in the South Brazil Bight ecosystem

The issue of whether loliginid squid can influence the average structure of marine ecosystems in a keystone role, i.e. a strong effect with relatively low biomass, has not yet been examined. Here, the diet of Loligo plei in inner shelf waters of the South Brazil Bight was examined, as a first step, based on the stomach contents of 2200 squid hand-jigged in shallow water (, 30 m) and taken as bycatch of shrimp trawlers in deeper water (30-100 m). Diet varied by size, season, and fishing zone. Stomachs were not empty in similar to 12%, with more empty during winter. The range of mantle lengths of squid caught by jigging (101-356 mm) appeared to differ from the squid trawled (30-236 mm), and the diet also differed. Food categories recorded in deeper water did not include amphipods or polychaetes, but in both fishing areas, fish were the most common prey. The fish prey identified included Trachurus lathami, small pelagic species, trichiurids, and Merluccius hubbsi. Demersal species, such as Ctenosciaena gracilicirrhus, and flatfish were also present. An ecosystem network model is updated through which a mixed-trophic impact matrix and ""keystoneness"" indicators were calculated. Loligo plei represents an important link between pelagic and demersal energy pathways, with high indices of keystoneness.

Spatial regimes: dynamics of intentional homicides in the city of Sao Paulo between 2000 and 2008

Objective. To identify the existence of spatial and temporal patterns in the occurrence of intentional homicides in the municipality of Sao Paulo (MSP), Brazil, and to discuss the analytical value of taking such patterns into account when designing studies that address the dynamics and factors associated with the incidence of homicides. Methods. A longitudinal ecological study was conducted, having as units of analysis 13 205 census tracts and the 96 census districts that congregate these sectors in Sao Paulo. All intentional homicides reported in the city between 2000 and 2008 were analyzed. The gross homicide rates per 100 000 population was calculated as well as the global and local Bayesian estimates for each census tract during the study period. To verify the possibility of identifying different patterns of the spatial distribution of homicides, we used BoxMap and Moran's I index. Results. The homicide trends in the city of Sao Paulo in the last decade were not homogeneous and systematic. Instead, seven patterns of spatial distribution were identified; that is, seven spatial regimes for the occurrence of intentional homicides, considering the homicide rates within each census tract as well as the rates in adjacent tracts. These spatial distribution regimes were not contained within the limits of the census tracts and districts. Conclusions. The results show the importance of analyzing the spatial distribution of social phenomena without restriction of political and administrative boundaries.

Oscillatory electro-oxidation of glycerol on platinum

This paper describes the experimental study of the oscillatory electro-oxidation of glycerol on platinum under galvanostatic control. The system was investigated in both acidic and alkaline media and for different glycerol concentrations. In acidic supporting electrolyte, the oscillatory behavior is rather simple and the main features such as period, amplitude and waveform are barely affected by the glycerol concentration. A more complex picture including the presence of different temporal patterns and strong dependence with glycerol concentration emerges in alkaline medium. In both media, the composite oscillations visit two clearly discernible potential windows, and potential oscillations in alkaline media are observed only when the working electrode is kept stationary. The mechanistic implications of our findings are discussed in connection with available data obtained under close-to-equilibrium conditions. (C) 2012 Elsevier Ltd. All rights reserved.

Changes in phytoplankton composition in response to tides, wind-induced mixing conditions, and freshwater outflows in an urbanised estuarine complex

Recent reports have shown an increase in potentially harmful phytoplankton in Santos bay (Southeastern Brazilian Coast), located in a highly urbanised estuarine complex. Prediction of blooms is, thus, essential but the phytoplankton community structure in very dynamic regions is difficult to determine. In the present work, we discriminate bloom forming microphytoplankton dominance and their relationship to physical and meteorological variables to look for patterns observed in different tides and seasons. Comparing 8 distinct situations, we found five scenarios of dominance that could be related to winds, tides and rainfall: i) Surfers, diatoms occurring during high surf zone energies; ii) Sinkers, represented by larger celled diatoms during spring tide, after periods of high precipitation rates; iii) Opportunistic mixers, composed of chain forming diatoms with small or elongate cells occurring during neap tides; iv) Local mixers, microplanktonic diatoms and dinoflagellates which occurred throughout the 298 sampling stations; and v) Mixotrophic dinoflagellates, after intense estuarine discharges. Results suggest alterations in the temporal patterns for some bloom-forming species, while others appeared in abundances above safe limits for public health. This approach can also illustrate possible impacts of changes in freshwater discharge in highly urbanised estuaries.

Disruption of endogenous tidal rhythms of larval release linked to food supply and heat stress in an intertidal barnacle

The timing of larval release may greatly affect the survivorship and distribution of pelagic stages and reveal important aspects of life history tactics in marine invertebrates. Endogenous rhythms of breeding individuals and populations are valuable indicators of selected strategies because they are free of the neutral effect of stochastic environmental variation. The high-shore intertidal barnacle Chthamalus bisinuatus exhibits endogenous tidal and tidal amplitude rhythms in a way that larval release would more likely occur during fortnightly neap periods at high tide. Such timing would minimize larval loss due to stranding and promote larval retention close to shore. This fully explains temporal patterns in populations facing the open sea and inhabiting eutrophic areas. However, rhythmic activity breaks down to an irregular pattern in a population within the São Sebastião Channel subjected to large variation of food supply around a mesotrophic average. Peaks of chl a concentration precede release events by 6 d, suggesting resource limitation for egg production within the channel. Also, extreme daily temperatures imposing mortality risk correlate to release rate just 1 d ahead, suggesting a terminal reproductive strategy. Oceanographic conditions apparently dictate whether barnacles follow a rhythmic trend of larval release supported by endogenous timing or, alternatively, respond to the stochastic variation of key environmental factors, resulting in an erratic temporal pattern.

Decadal changes in the structure of Cymodocea nodosa seagrass meadows: natural vs. human influences

[EN] Seagrass meadows are deteriorating worldwide. However, numerous declines are still unreported, which avoid accurate evaluations of seagrass global trends. This is particularly relevant for the western African coast and nearby oceanic archipelagos in the eastern Atlantic. The seagrass Cymodocea nodosa is an ecological engineer on shallow soft bottoms of the Canary Islands. A comparative decadal study was conducted in 21 C. nodosa seagrass meadows at Gran Canaria Island to compare the structure (shoot density, leaf length and cover) between 2003 and 2012. Overall, 11 meadows exhibited a severe regression, while 10 remained relatively stable. During this period, natural influences (sea surface temperature, Chlorophyll-a concentration and PAR light, as well as the number of storm episodes detaching seagrasses) had a low predictive power on temporal patterns in seagrass structure. In contrast, proximity from a range of human-mediated influences (e.g. the number of outfalls and ports) seem to be related to the loss of seagrass; the rate of seagrass erosion between 2003 and 2012 was significantly predicted by the number of human-mediated impacts around each meadow. This result highlights promoting management actions to conserve meadows of C. nodosa at the study region through efficient management of local impacts

Per un'indagine comparata della relazione voce-movimento nel performer

The present study investigates the principles that effect the relationship between voice and movement in performance. The topic stresses a contemporary tendency, which emerges from the work of numerous artits and looks into a research field that has not yet been well explored. The research arises from what I observed and experienced during my performance practical work and what I deepened after theorical studies: expression through movement and voice reflects constant principles. The first two chapters of the former study analyze the compared lines of the inquiry, from a theoretical point of view (interior and exterior voice-movement spatial patterns, and temporal patterns) and a practical point of view referring to body, action and relation. The third one is a survey on 'vocal gesture' as devised by Francesca della Monica, a topic that finds here the first academic investigation, built after nine years sudies with the artist on the oral sources of her teaching. The research is based on practical and theorical sources (especially philosophical studies of Giovanni Piana, Carlo Serra, Merleau-Ponty; performing studies of Grotowski, Laban, Dalcroze, Tomatis; ancient greek philosophy and literature; bodywork tecqniques as Kineseology, Body-mind centering, Alexander, Feldenkrais). The purpose of the study is to theorize, sistematyze and expose clear lines of compared investigation awakening the performer's interest on a central issue of his work and drawing the researcher's attention to make further focusing on the matter. Abstract (Italian) La ricerca va incontro a una tendenza che la contemporaneità pone in risalto con l'opera di numerosi artisti, investigando un campo ancora poco visitato a livello critico. Essa teorizza, sistematizza ed espone le costanti riscontrate nella relazione tra voce e movimento. L'indagine deriva dal presupposto, a me suggerito dalla pratica e dallo scambio con maestri e performer, e qui approfondito e restituito a livello teorico, che nella danza e nel canto, nell'espressione attraverso il movimento o attraverso la voce, si riflettono gli stessi principi. La tesi è articolata in tre capitoli: i primi due sviluppano le linee di indagine comparata, prima da un punto di vista filosofico e poi da un punto di vista pratico, il terzo porta alla luce il concetto di gesto-vocale come inteso da Francesca della Monica, di cui questo studio rappresenta il primo contributo scientifico, aprendo una ricerca nuova agli studi di settore. Il primo capitolo, 'Risonanze', sviluppa le premesse filosofiche della questione, introduce il corpo come veicolo di voce e movimento, affronta il tema del movimento della voce nello spazio interno del corpo e nello spazio di relazione. Legge poi il movimento in termini temporali, secondo i concetti di istante, ritmo, forma e flusso. Il secondo capitolo, 'Costanti', espone le costanti concrete della relazione voce-movimento in riferimento allo spazio interno del corpo, all'azione, allo spazio esterno di relazione. Il terzo capitolo, 'Confini', analizza il gesto vocale, come inteso da Francesca della Monica, concetto sintesi dell'intera ricerca poiché integra, nella sua essenza, il movimento fisico e vocale, restituendo e approfondendo lo spettro di riflessioni emerse nei primi due capitoli. Il gesto vocale, nella sua accezione espressiva, così come il lavoro di Francesca della Monica, è ancora estraneo agli studi di settore e trova in questo studio un primo contributo accademico. Le fonti sono quelle dell'insegnamento orale di Francesca della Monica, che ho seguito per nove anni, fino a desumerne una mia personale sistematizzazione, integrata con altri punti di vista critici. Analizzo i diversi livelli di profondità del gesto vocale scandendo il tema secondo la categoria della relazione: relazioni motorie, relazioni materiche, relazioni spaziali, temporali, compositive e sinestesiche. Le fonti della ricerca sono scaturite da due sorgenti, quella sul campo, e quella della teoria, confluite qui in un unico flusso. Le fonti 'in presa diretta' sono state avvalorate e confrontate con le fonti relative agli studi di settore (in particolare per la filosofia Giovanni Piana, Carlo Serra, Merleau-Ponty, per il teatro, il canto e la danza Grotowski, Laban, Dalcroze, Tomatis) e le bodywork techniques (Kinesiologia, Body-mind centering, metodo Alexander, metodo Feldenkrais). Ampio spazio viene dato alla grecità antica, che propone sull'espressione di voce e movimento un pensiero integrato carico di speculazioni che racchiudono in nuce i principi sviluppati. Lo studio tenta di offrire un livello di lettura idoneo a suscitare l'interesse del performer, e a valere come momento di indagine per lo studioso, che possa da queste basi operare approfondimenti sulle connessioni proposte. L'obiettivo è restituire la conoscenza, intuita in virtù della pratica, elaborata ed arricchita grazie alla teoria, su un nodo fondamentale per gli studi teatrali e recente oggetto di attenzione da parte di critici e artisti.

Megistobenthic faunal diversity of the Antalya Gulf: Crustacea

The spatio-temporal distribution of megistobenthic crustacean assemblages from the Antalya Gulf, located in the Levantine Sea is described. In order to provide a comprehensive overview of the spatio-temporal patterns of the crustacean community, 3 transect including depth of 10, 25, 75, 125 and 200 m, were studied between 2014 and 2015 to investigate their association with a set of environmental parameters in representative months of each season (spring, summer, autumn and winter). For its economic importance in Levantine waters, a focus analysis of deep-water rose shrimp Parapenaeus longirostris (Lucas, 1846) was done, to investigate the length frequency composition of the population of the Antalya Gulf. A total of 58 crustacean species were encountered in the study area, of these species identified, 18 species were recognized as alien species in the Mediterranean Sea. Throughout the year the most frequent species of the study were the hermit crab Pagurus prideaux (Leach, 1815) and Parapenaeus longirostris (Lucas, 1846) followed by the Indo-Pacific swimming crab Charybdis longicollis (Leene, 1938) and by the invasive shrimp Marsupenaeus japonicus (Spence Bate, 1888). Few species contributing to a high amount to the total biomass were found throughout the year. These species were Charybdis longicollis and Parapenaeus longirostris. Stations of the study area showed similar values of diversity indices of benthic crustacean community among the three transect. The highest values of faunistic indices were detected in autumn and winter (October and February), and also varied along the depth gradient, with the highest values found between 25 and 75 meters. The multivariate analyses conducted on the abundance data point out major differences between depths and between seasons. Therefore, according to cluster analysis and ordination over abundance and biomass, three main crustacean assemblages were detected: the first corresponding to shallow bottoms (10, 25 meters), the second corresponding to intermediate waters (75 meters) and the last to deeper waters (125, 200 meters). Depth was the main factor governing the distribution of megistobenthic crustacean in the area. Besides the depth, the structure of the sediment is the most important factor in determining the crustacean assemblage. Therefore, all factors governing the crustacean distribution were found to be related to the bottom depth. The population of Parapenaeus longirostris in the Antalya Gulf showed significant differences in depth. It was found that females dominated the population of the study area (65.11%), and were significantly larger than males for each cohort identified. The size-weight relationships revealed a slight negative allometry in growth, a bit more pronounced in females than in males.

Debris-flow activity in abandoned channels of the Manival torrent reconstructed with LiDAR and tree-ring data

Hydrogeomorphic processes are a major threat in many parts of the Alps, where they periodically damage infrastructure, disrupt transportation corridors or even cause loss of life. Nonetheless, past torrential activity and the analysis of areas affected during particular events remain often imprecise. It was therefore the purpose of this study to reconstruct spatio-temporal patterns of past debris-flow activity in abandoned channels on the forested cone of the Manival torrent (Massif de la Chartreuse, French Prealps). A Light Detecting and Ranging (LiDAR) generated Digital Elevation Model (DEM) was used to identify five abandoned channels and related depositional forms (lobes, lateral levees) in the proximal alluvial fan of the torrent. A total of 156 Scots pine trees (Pinus sylvestris L.) with clear signs of debris flow events was analyzed and growth disturbances (GD) assessed, such as callus tissue, the onset of compression wood or abrupt growth suppression. In total, 375 GD were identified in the tree-ring samples, pointing to 13 debris-flow events for the period 1931–2008. While debris flows appear to be very common at Manival, they have only rarely propagated outside the main channel over the past 80 years. Furthermore, analysis of the spatial distribution of disturbed trees contributed to the identification of four patterns of debris-flow routing and led to the determination of three preferential breakout locations. Finally, the results of this study demonstrate that the temporal distribution of debris flows did not exhibit significant variations since the beginning of the 20th century.

Interleukin-6 is an efficacious marker of axonal transport disruption during experimental glaucoma and stimulates neuritogenesis in cultured retinal ganglion cells

It is increasingly recognised that chronically activated glia contribute to the pathology of various neurodegenerative diseases, including glaucoma. One means by which this can occur is through the release of neurotoxic, proinflammatory factors. In the current study, we therefore investigated the spatio-temporal patterns of expression of three such cytokines, IL-1β, TNFα and IL-6, in a validated rat model of experimental glaucoma. First, only weak evidence was found for increased expression of IL-1β and TNFα following induction of ocular hypertension. Second, and much more striking, was that robust evidence was uncovered showing IL-6 to be synthesised by injured retinal ganglion cells following elevation of intraocular pressure and transported in an orthograde fashion along the nerve, accumulating at sites of axonal disruption in the optic nerve head. Verification that IL-6 represents a novel marker of disrupted axonal transport in this model was obtained by performing double labelling immunofluorescence with recognised markers of fast axonal transport. The stimulus for IL-6 synthesis and axonal transport during experimental glaucoma arose from axonal injury rather than ocular hypertension, as the response was identical after optic nerve crush and bilateral occlusion of the carotid arteries, each of which is independent of elevated intraocular pressure. Moreover, the response of IL-6 was not a generalised feature of the gp130 family of cytokines, as it was not mimicked by another family member, ciliary neurotrophic factor. Finally, further study suggested that IL-6 may be an early part of the endogenous regenerative response as the cytokine colocalised with growth-associated membrane phosphoprotein-43 in some putative regenerating axons, and potently stimulated neuritogenesis in retinal ganglion cells in culture, an effect that was additive to that of ciliary neurotrophic factor. These data comprise clear evidence that IL-6 is actively involved in the attempt of injured retinal ganglion cells to regenerate their axons.

Change mechanisms of schema-centered group psychotherapy with personality disorder patients

Background This study addressed the temporal properties of personality disorders and their treatment by schema-centered group psychotherapy. It investigated the change mechanisms of psychotherapy using a novel method by which psychotherapy can be modeled explicitly in the temporal domain. Methodology and Findings 69 patients were assigned to a specific schema-centered behavioral group psychotherapy, 26 to social skills training as a control condition. The largest diagnostic subgroups were narcissistic and borderline personality disorder. Both treatments offered 30 group sessions of 100 min duration each, at a frequency of two sessions per week. Therapy process was described by components resulting from principal component analysis of patients' session-reports that were obtained after each session. These patient-assessed components were Clarification, Bond, Rejection, and Emotional Activation. The statistical approach focused on time-lagged associations of components using time-series panel analysis. This method provided a detailed quantitative representation of therapy process. It was found that Clarification played a core role in schema-centered psychotherapy, reducing rejection and regulating the emotion of patients. This was also a change mechanism linked to therapy outcome. Conclusions/Significance The introduced process-oriented methodology allowed to highlight the mechanisms by which psychotherapeutic treatment became effective. Additionally, process models depicted the actual patterns that differentiated specific diagnostic subgroups. Time-series analysis explores Granger causality, a non-experimental approximation of causality based on temporal sequences. This methodology, resting upon naturalistic data, can explicate mechanisms of action in psychotherapy research and illustrate the temporal patterns underlying personality disorders.

Effects of in situ freezing on soil net nitrogen mineralization and net nitrification in fertilized grassland of northern China

Effects of soil freezing on nitrogen (N) mineralization have been the subject of increased attention in the ecological literature, though fewer studies have examined N mineralization responses to successive mild freezing, severe freezing and cyclic freeze–thaw events. Even less is known about relationships of responses to soil N status. This study measured soil N mineralization and nitrification in the field along an experimental N gradient in a grassland of northern China during the dormant season (October 2005–April 2006), a period in which freezing naturally occurs. Net N mineralization exhibited great temporal variability, with nitrification being the predominant N transformation process. Soil microbial biomass C and N and extractable NH4 + pools declined by 40, 52, and 56%, respectively, in April 2006, compared with their initial concentrations in October 2005; soil NO3– pools increased by 84%. Temporal patterns of N mineralization were correlated with soil microbial biomass C and N. N mineralization and nitrification increased linearly with added N. Microbial biomass C in treated soils increased by 10% relative to controls, whereas microbial N declined by 9%. Results further suggest that freezing events greatly alter soil N dynamics in the dormant season at this site, with considerable available N accumulating during this period.