990 resultados para Head-first burrower


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Plasmodium falciparum (Pf) malaria causes 200 million cases worldwide, 8 million being severe and complicated leading to similar to 1 million deaths and similar to 100,000 abortions annually. Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) has been implicated in cytoadherence and infected erythrocyte rosette formation, associated with cerebral malaria; chondroitin sulphate-A attachment and infected erythrocyte sequestration related to pregnancy-associated malaria and other severe forms of disease. An endothelial cell high activity binding peptide is described in several of this similar to 300 kDa hypervariable protein's domains displaying a conserved motif (GACxPxRRxxLC); it established H-bonds with other binding peptides to mediate red blood cell group A and chondroitin sulphate attachment. This motif (when properly modified) induced PfEMP1-specific strain-transcending, fully-protective immunity for the first time in experimental challenge in Aotus monkeys, opening the way forward for a long sought-after vaccine against severe malaria.

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The first mycetome was discovered more than 340 yr ago in the human louse. Despite the remarkable biology and medical and social importance of human lice, its primary endosymbiont has eluded identification and characterization. Here, we report the host-symbiont interaction of the mycetomic bacterium of the head louse Pediculus humanus capitis and the body louse P. h. humanus. The endosymbiont represents a new bacterial lineage in the -Proteobacteria. Its closest sequenced relative is Arsenophonus nasoniae, from which it differs by more than 10%. A. nasoniae is a male-killing endosymbiont of jewel wasps. Using microdissection and multiphoton confocal microscopy, we show the remarkable interaction of this bacterium with its host. This endosymbiont is unique because it occupies sequentially four different mycetomes during the development of its host, undergoes three cycles of proliferation, changes in length from 2–4 µm to more than 100 µm, and has two extracellular migrations, during one of which the endosymbionts have to outrun its host’s immune cells. The host and its symbiont have evolved one of the most complex interactions: two provisional or transitory mycetomes, a main mycetome and a paired filial mycetome. Despite the close relatedness of body and head lice, differences are present in the mycetomic provisioning and the immunological response.—Perotti, M. A., Allen, J. M., Reed, D. L., Braig, H. R. Host-symbiont interactions of the primary endosymbiont of human head and body lice.

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Perfluorodecalin (C10F18) has a range of medical uses that have led to small releases. Recently, it has been proposed as a carrier of vaccines, which could lead to significantly larger emissions. Since its emissions are controlled under the Kyoto Protocol, it is important that values for the global warming potential (GWP) are available. For a 50:50 mixture of the two isomers of perfluorodecalin, laboratory measurements, supplemented by theoretical calculations, give an integrated absorption cross-section of 3.91 x 10(-16) cm(2) molecule(-1) cm(-1) over the spectral region 0-1500 cm(-1); calculations yield a radiative efficiency of 0.56 W m(-2) ppbv(-1) and a 100-year GWP, relative to carbon dioxide, of 7200 assuming a lifetime of 1000 years. We report the first atmospheric measurements of perfluorodecalin, at Bristol, UK and Mace Head, Ireland, where volume mixing ratios are about 1.5 x 10(-15). At these concentrations, it makes a trivial contribution to climate change, but on a per molecule basis it is a potent greenhouse gas, indicating the need for careful assessment of its possible future usage. (c) 2005 Elsevier Ltd. All rights reserved.

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The North Atlantic Marine Boundary Layer Experiment (NAMBLEX), involving over 50 scientists from 12 institutions, took place at Mace Head, Ireland (53.32° N, 9.90° W), between 23 July and 4 September 2002. A wide range of state-of-the-art instrumentation enabled detailed measurements of the boundary layer structure and atmospheric composition in the gas and aerosol phase to be made, providing one of the most comprehensive in situ studies of the marine boundary layer to date. This overview paper describes the aims of the NAMBLEX project in the context of previous field campaigns in the Marine Boundary Layer (MBL), the overall layout of the site, a summary of the instrumentation deployed, the temporal coverage of the measurement data, and the numerical models used to interpret the field data. Measurements of some trace species were made for the first time during the campaign, which was characterised by predominantly clean air of marine origin, but more polluted air with higher levels of NOx originating from continental regions was also experienced. This paper provides a summary of the meteorological measurements and Planetary Boundary Layer (PBL) structure measurements, presents time series of some of the longer-lived trace species (O3, CO, H2, DMS, CH4, NMHC, NOx, NOy, PAN) and summarises measurements of other species that are described in more detail in other papers within this special issue, namely oxygenated VOCs, HCHO, peroxides, organo-halogenated species, a range of shorter lived halogen species (I2, OIO, IO, BrO), NO3 radicals, photolysis frequencies, the free radicals OH, HO2 and (HO2+Σ RO2), as well as a summary of the aerosol measurements. NAMBLEX was supported by measurements made in the vicinity of Mace Head using the NERC Dornier-228 aircraft. Using ECMWF wind-fields, calculations were made of the air-mass trajectories arriving at Mace Head during NAMBLEX, and were analysed together with both meteorological and trace-gas measurements. In this paper a chemical climatology for the duration of the campaign is presented to interpret the distribution of air-mass origins and emission sources, and to provide a convenient framework of air-mass classification that is used by other papers in this issue for the interpretation of observed variability in levels of trace gases and aerosols.

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A first step in interpreting the wide variation in trace gas concentrations measured over time at a given site is to classify the data according to the prevailing weather conditions. In order to classify measurements made during two intensive field campaigns at Mace Head, on the west coast of Ireland, an objective method of assigning data to different weather types has been developed. Air-mass back trajectories calculated using winds from ECMWF analyses, arriving at the site in 1995–1997, were allocated to clusters based on a statistical analysis of the latitude, longitude and pressure of the trajectory at 12 h intervals over 5 days. The robustness of the analysis was assessed by using an ensemble of back trajectories calculated for four points around Mace Head. Separate analyses were made for each of the 3 years, and for four 3-month periods. The use of these clusters in classifying ground-based ozone measurements at Mace Head is described, including the need to exclude data which have been influenced by local perturbations to the regional flow pattern, for example, by sea breezes. Even with a limited data set, based on 2 months of intensive field measurements in 1996 and 1997, there are statistically significant differences in ozone concentrations in air from the different clusters. The limitations of this type of analysis for classification and interpretation of ground-based chemistry measurements are discussed.

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The authors demonstrate four real-time reactive responses to movement in everyday scenes using an active head/eye platform. They first describe the design and realization of a high-bandwidth four-degree-of-freedom head/eye platform and visual feedback loop for the exploration of motion processing within active vision. The vision system divides processing into two scales and two broad functions. At a coarse, quasi-peripheral scale, detection and segmentation of new motion occurs across the whole image, and at fine scale, tracking of already detected motion takes place within a foveal region. Several simple coarse scale motion sensors which run concurrently at 25 Hz with latencies around 100 ms are detailed. The use of these sensors are discussed to drive the following real-time responses: (1) head/eye saccades to moving regions of interest; (2) a panic response to looming motion; (3) an opto-kinetic response to continuous motion across the image and (4) smooth pursuit of a moving target using motion alone.

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The present study investigates the parsing of pre-nominal relative clauses (RCs) in children for the first time with a realtime methodology that reveals moment-to-moment processing patterns as the sentence unfolds. A self-paced listening experiment with Turkish-speaking children (aged 5–8) and adults showed that both groups display a sign of processing cost both in subject and object RCs at different points through the flow of the utterance when integrating the cues that are uninformative (i.e., ambiguous in function) and that are structurally and probabilistically unexpected. Both groups show a processing facilitation as soon as the morphosyntactic dependencies are completed and parse the unbounded dependencies rapidly using the morphosyntactic cues rather than waiting for the clause-final filler. These findings show that five-year-old children show similar patterns to adults in processing the morphosyntactic cues incrementally and in forming expectations about the rest of the utterance on the basis of the probabilistic model of their language.

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This paper seeks to describe and discuss the impact of inspections of schools in Sweden. It outlines the political context, based on New Public Management (NPM) theory, according to what role the Schools Inspectorate is supposed to play in order to govern and control. Attention is also devoted, referring an on-going case study, to how inspections influence head teachers and their leadership in their everyday work.   Reports from the Schools inspectorate are public. This forces both politicians and head teachers to take measures. In this case, the head teachers perceived that the inspection reports confirmed what they already knew, but it also gave them an alibi and a tool to push their teachers to take part in everyday school development work. During the first year after the inspection the head teachers mainly strived to adjust formal deficiencies in local steering documents. However, some of the deviations reported from the Schools inspectorate are regarding pedagogical problems that are complicated and difficult to handle. As interventions in many cases will show up much later the results are, for example as increased goal fulfilment, in this case, still an open question. Nevertheless, it seems obvious that the Schools Inspectorate must be seen as a result of the governing philosophy that denotes New Public Management NPM).

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This paper seeks to describe and discuss the impact of inspections of schools in Sweden. It outlines the political context, based on New Public Management (NPM) theory, according to what role the Schools Inspectorate is supposed to play in order to govern and control. Attention is also devoted, referring an on-going case study, to how inspections influence head teachers and their leadership in their everyday work.   Reports from the Schools inspectorate are public. This forces both politicians and head teachers to take measures. In this case, the head teachers perceived that the inspection reports confirmed what they already knew, but it also gave them an alibi and a tool to push their teachers to take part in everyday school development work. During the first year after the inspection the head teachers mainly strived to adjust formal deficiencies in local steering documents. However, some of the deviations reported from the Schools inspectorate are regarding pedagogical problems that are complicated and difficult to handle. As interventions in many cases will show up much later the results are, for example as increased goal fulfilment, in this case, still an open question. Nevertheless, it seems obvious that the Schools Inspectorate must be seen as a result of the governing philosophy that denotes New Public Management NPM).

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Although there is a generally accepted framework for the Permian marine biogeography of Australia, significant uncertainties remain concerning the temporal biogeographical changes closely related to the timing of Permian glacial-interglacial events. Several recent studies along these research lines demonstrate the importance of a reliable high-resolution biostratigraphical timescale for paleobiogeographical and paleoclimatic reconstructions. This paper provides, for the first time, a full taxonomic and biostratigraphical study of the brachiopod fauna from the Wasp Head Formation, southern Sydney Basin, southeastern Australia. The fauna is associated with deposits of the first Permian glacial interval suggested for eastern Australia. Three brachiopod assemblages are recognized. The lower and middle assemblages contain scarce brachiopods although associated bivalves are comparatively more common. Despite very low diversity and low abundance, these two brachiopod assemblages contain characteristic species of the Strophalosia concentrica and Strophalosia subcircularis brachiopod zones, both considered of late Asselian age. The third assemblage, occurring in the uppermost part of the formation, contains more brachiopods than bivalves and is referred to early Sakmarian in age. The species diversity and stratigraphic occurrences of the brachiopod assemblages in relation to sedimentary facies suggest that the lower two assemblages may represent an intra-glacial interval while the younger third assemblage, characterized by abundant occurrences of Trigonotreta and Tomiopsis species, accompanied by the bivalve Eurydesma, is more indicative of a post-glacial benthic marine fauna comparable to coeval brachiopod faunas found elsewhere in Gondwana. © 2014, The Paleontological Society.

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Aripiprazole and risperidone are the only FDA approved medications for treating irritability in autistic disorder, however there are no head-to-head data comparing these agents. This is the first prospective randomized clinical trial comparing the safety and efficacy of these two medications in patients with autism spectrum disorders. Fifty nine children and adolescents with autism spectrum disorders were randomized to receive either aripiprazole or risperidone for 2 months. The primary outcome measure was change in Aberrant Behavior Checklist (ABC) scores. Adverse events were assessed. Aripiprazole as well as risperidone lowered ABC scores during 2 months. The rates of adverse effects were not significantly different between the two groups. The safety and efficacy of aripiprazole (mean dose 5.5 mg/day) and risperidone (mean dose 1.12 mg/day) were comparable. The choice between these two medications should be on the basis of clinical equipoise considering the patient's preference and clinical profile.

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Worldwide, there has been a rapid increase in both the use of mobile technologies as a conduit for student learning and the use of wearable cameras to record sporting and recreational activities. The Expert in My Pocket project (EiMP) has combined these two technologies to produce a repository of freely available short videos and supporting materials to enhance student development of psychomotor clinical skills. The videos are presented from a first person point of view (1PPOV) with expert health professionals ‘thinking aloud’ as they demonstrate selected skills. Research indicates that students and educators overwhelmingly support the concept of EiMP videos and more importantly value the 1PPOV as an authentic view. This paper demonstrates the techniques and equipment employed to produce these videos, which consisted of a chest or head mounted GoPro camera operated via an iPad. Additionally, the paper explains another innovative feature, Quick Response (QR) Codes, that when linked to the videos placed on equipment assists with “just in time” mobile learning.

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This paper presents the outcomes of an 18-month developmental action research study to enhance the governance capability of a national sport organization. Bowls Australia, the national governing body for lawn bowls
in Australia, includes nine independent state and territory member-associations. An intervention was designed and implemented with the Bowls Australia Board. The purpose of the intervention was to enact collaborative governance to overcome a perceived cultural malaise in the governance of the sport. This study is one of the first to examine collaborative governance in a federal sport structure. Results demonstrate the utility of collaborative governance to overcome adversarial national, member-state relations for the purpose of establishing a common and unifying vision for bowls, while also enhancing governance capability. This study identified the importance of collective board leadership in governance decision-making throughout the sport. It also highlights future research directions in relation to collective board leadership in federal governance structures.

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Though many of those who decided to report wrongdoings in their organizations were able to tell their stories (e.g. Bamford, 2014, Armenakis 2004), it is fair to say that there is still much left to uncover. The paper aims to contribute to the literature in three ways. First, it provides preliminary evidence that the wrongdoing linked with individual financial loss leads to higher whistleblowing rate. Secondly, it shows how the experience of anger is related to the higher likelihood to report the wrongdoer but only if the wrongful act is perceived as a cause of one’s financial loss. Finally, the paper establishes first steps for the future development of an experimental procedure that would enable to predict, and measure whistleblowing behavior in the lab environment.

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Adequate environmental temperature during the brooding period is very important to future broiler performance. Thus, the objective of this study was to investigate the extent to which environmental temperature affects the body weight and cloacal and surface (back, head, wing, and shank) temperatures. The study also investigated the sensible heat loss by radiation of broiler chicks reared at three environmental temperatures (35, 25, and 20 degrees C) up to 7 days of life. The results showed that chicks raised at low environmental temperature (20 degrees C) had lower body weight at 7 days of age. Birds kept at 20 degrees C also had significantly lower cloacal and surface temperatures than did other birds. The most marked difference was seen in the shanks. These findings revealed that body weight declined in chicks reared at 20 degrees C, and radiant heat loss (W) was nine times higher than for the birds kept at 35 degrees C at 7 days of age.