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It has been suggested that the evidence used to support a decision to move our eyes and the confidence we have in that decision are derived from a common source. Alternatively, confidence may be based on further post-decisional processes. In three experiments we examined this. In Experiment 1, participants chose between two targets on the basis of varying levels of evidence (i.e., the direction of motion coherence in a Random-Dot-Kinematogram). They indicated this choice by making a saccade to one of two targets and then indicated their confidence. Saccade trajectory deviation was taken as a measure of the inhibition of the non-selected target. We found that as evidence increased so did confidence and deviations of saccade trajectory away from the non-selected target. However, a correlational analysis suggested they were not related. In Experiment 2 an option to opt-out of the choice was offered on some trials if choice proved too difficult. In this way we isolated trials on which confidence in target selection was high (i.e., when the option to opt-out was available but not taken). Again saccade trajectory deviations were found not to differ in relation to confidence. In Experiment 3 we directly manipulated confidence, such that participants had high or low task confidence. They showed no differences in saccade trajectory deviations. These results support post-decisional accounts of confidence: evidence supporting the decision to move the eyes is reflected in saccade control, but the confidence that we have in that choice is subject to further post-decisional processes.

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It has long been known that the path (trajectory) taken by the eye to land on a target is rarely straight (Yarbus, 1967). Furthermore, the magnitude and direction of this natural tendency for curvature can be modulated by the presence of a competing distractor stimu­ lus presented along with the saccade target. The distractor­related modulation of saccade trajectories provides a subtle measure of the underlying competitive processes involved in saccade target selection. Here we review some of our own studies into the effects distract­ ors have on saccade trajectories, which can be regarded as a way of probing the competit­ ive balance between target and distractor salience.

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Radar refractivity retrievals can capture near-surface humidity changes, but noisy phase changes of the ground clutter returns limit the accuracy for both klystron- and magnetron-based systems. Observations with a C-band (5.6 cm) magnetron weather radar indicate that the correction for phase changes introduced by local oscillator frequency changes leads to refractivity errors no larger than 0.25 N units: equivalent to a relative humidity change of only 0.25% at 20°C. Requested stable local oscillator (STALO) frequency changes were accurate to 0.002 ppm based on laboratory measurements. More serious are the random phase change errors introduced when targets are not at the range-gate center and there are changes in the transmitter frequency (ΔfTx) or the refractivity (ΔN). Observations at C band with a 2-μs pulse show an additional 66° of phase change noise for a ΔfTx of 190 kHz (34 ppm); this allows the effect due to ΔN to be predicted. Even at S band with klystron transmitters, significant phase change noise should occur when a large ΔN develops relative to the reference period [e.g., ~55° when ΔN = 60 for the Next Generation Weather Radar (NEXRAD) radars]. At shorter wavelengths (e.g., C and X band) and with magnetron transmitters in particular, refractivity retrievals relative to an earlier reference period are even more difficult, and operational retrievals may be restricted to changes over shorter (e.g., hourly) periods of time. Target location errors can be reduced by using a shorter pulse or identified by a new technique making alternate measurements at two closely spaced frequencies, which could even be achieved with a dual–pulse repetition frequency (PRF) operation of a magnetron transmitter.

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Insect pollinated mass flowering crops are becoming more widespread and there is a need to understand which insects are primarily responsible for the pollination of these crops so conservation measures can be appropriately targeted in the face of pollinator declines. This study used field surveys in conjunction with cage manipulations to identify the relative contributions of different pollinator taxa to the pollination of two widespread flowering crops, field beans and oilseed rape. Flower visiting pollinator communities observed in the field were distinct for each crop; while field beans were visited primarily by a few bumblebee species, multiple pollinator taxa visited oilseed, and the composition of this pollinator community was highly variable spatially and temporally. Neither pollinator community, however, appears to be meeting the demands of crops in our study regions. Cage manipulations showed that multiple taxa can effectively pollinate both oilseed and field beans, but bumblebees are particularly effective bean pollinators. Combining field observations and cage manipulations demonstrated that the pollination demands of these two mass flowering crops are highly contrasting, one would benefit from management to increase the abundance of some key taxa, whilst for the other, boosting overall pollinator abundance and diversity would be more appropriate. Our findings highlight the need for crop specific mitigation strategies that are targeted at conserving specific pollinator taxa (or group of taxa) that are both active and capable of crop pollination in order to reduce pollination deficits and meet the demands of future crop production.

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In the present study, to shed light on a role of positional error correction mechanism and prediction mechanism in the proactive control discovered earlier, we carried out a visual tracking experiment, in which the region where target was shown, was regulated in a circular orbit. Main results found in this research were following. Recognition of a time step, obtained from the environmental stimuli, is required for the predictive function. The period of the rhythm in the brain obtained from environmental stimuli is shortened about 10%, when the visual information is cut-off. The shortening of the period of the rhythm in the brain accelerates the motion as soon as the visual information is cut-off, and lets the hand motion precedes the target motion. Although the precedence of the hand in the blind region is reset by the environmental information when the target enters the visible region, the hand precedes in average the target when the predictive mechanism dominates the error-corrective mechanism.

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This essay analyses the transmission of the texts of Shakespeare's final plays, Pericles, Coriolanus, Cymbeline, The Winter’s Tale, The Tempest, Henry VIII and The Two Noble Kinsmen, from author to censor to stage to print and argues that he had refined his writing, revision and collaborative practices.

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Evolved resistance to fungicides is a major problem limiting our ability to control agricultural, medical and veterinary pathogens and is frequently associated with substitutions in the amino acid sequence of the target protein. The convention for describing amino-acid substitutions is to cite the wild type amino acid, the codon number and the new amino acid, using the one letter amino acid code. It has frequently been observed that orthologous amino acid mutations have been selected in different species by fungicides from the same mode of action class, but the amino acids have different numbers. These differences in numbering arise from the different lengths of the proteins in each species. The purpose of the current paper is to propose a system for unifying the labelling of amino acids in fungicide target proteins. To do this we have produced alignments between fungicide target proteins of relevant species fitted to a well-studied “archetype” species. Orthologous amino acids in all species are then assigned numerical “labels” based on the position of the amino acid in the archetype protein.

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In an attempt to evaluate correlations between several properties of comets we report the results of a cometary research involving a criterious analysis of gas and dust mass production rates in Comets 67P/Churyumov-Gerasimenko (main target of Rosetta Mission), 1P/Halley, Hyakutake (C/1996 B2), and 46P/Wirtanen and make a comparison between them. (C) 2009 COSPAR. Published by Elsevier Ltd. All rights reserved.

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Despite the favorable treatment of cranial nerve neuropathology in adulthood, some cases are resistant to therapy leading to permanent functional impairments In many cases, suitable treatment is problematic as the therapeutic target remains unknown Basic fibroblast growth factor (bFGF, FGF 2) is involved in neuronal maintenance and wound repair following nervous system lesions It is one of few neurotrophic molecules acting in autocrine, paracrine and intracrine fashions depending upon specific circumstances Peripheral cranial somatic motor neurons, i e hypoglossal (XII) neurons, may offer a unique opportunity to study cellular FGF 2 mechanisms as the molecule is present in the cytoplasm of neurons and in the nuclei of astrocytes of the central nervous system FGF-2 may trigger differential actions during development, maintenance and lesion of XII neurons because axotomy of those cells leads to cell death during neonatal ages, but not in adult life Moreover, the modulatory effects of astroglial FGF 2 and the Ca+2 binding protein S100 beta have been postulated in paracrine mechanisms after neuronal lesions In our study, adult Wistar rats received a unilateral crush or transection (with amputation of stumps) of XII nerve, and were sacrificed after 72 h or 11 days Brains were processed for immunohistochemical localization of neurofilaments (NF), with or without counterstaining for Nissl substance, ghat fibrillary acidic protein (GFAP, as a marker of astrocytes), S100 beta and FGF-2 The number of Nissl positive neurons of axotomized XII nucleus did not differ from controls The NF immunoreactivity increased in the perikarya and decreased in the neuropil of axotomized XII neurons 11 days after nerve crush or transection An astrocytic reaction was seen in the ipsilateral XII nucleus of the crushed or transected animals 72 h and 11 days after the surgery The nerve lesions did not change the number of FGF-2 neurons in the ipsilateral XII nucleus, however, the nerve transection increased the number of FGF-2 ghat profiles by 72 h and 11 days Microdensitometric image analysis revealed a short lasting decrease in the intensity of FGF 2 immunoreactivity in axotomized XII neurons by 72 h after nerve crush or transection and also an elevation of FGF-2 in the ipsilateral of ghat nuclei by 72h and 11 days after the two lesions S100 beta decreased in astrocytes of 11-day transected XII nucleus The two-color immunoperoxidase for the simultaneous detection of the GFAP/FGF-2 indicated FGF-2 upregulation in the nuclei of reactive astrocytes of the lesioned XII nucleus Astroglial FGF-2 may exert paracrine trophic actions in mature axotomized XII neurons and might represent a therapeutic target for neuroprotection in peripheral nerve pathology (C) 2009 Elsevier GmbH All rights reserved

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A regimen of low-protein diet induces a reduction of pancreatic islet function that is associated with development of metabolic disorders including diabetes and obesity afterward. In the present study, the influence of leucine supplementation on metabolic parameters, insulin secretion to glucose and to amino acids, as well as the levels of proteins that participate in the phosphatidylinositol 3-phosphate kinase (PI3K) pathway was investigated in malnourished rats. Four groups were fed with different diets for 12 weeks: a normal protein diet (17%) without (NP) or with leucine supplementation (NPL) or a low (6%)-protein diet without (LP) or with leucine supplementation (LPL). Leucine was given in the drinking water during the last 4 weeks. As indicated by the intraperitoneal glucose tolerance test, LPL rats exhibited increased glucose tolerance as compared with NPL group. Both NPL and LPL rats had higher circulating insulin levels than controls. The LPL rats also showed increased insulin secretion by pancreatic islets in response to glucose or arginine compared with those observed in islets from LP animals. Glucose oxidation was significantly reduced in NPL, LP, and LPL isolated islets as compared with NP; but no alteration was observed for leucine and glutamate oxidation among the 4 groups. Western blotting analysis demonstrated increased PI3K and mammalian target protein of rapamycin protein contents in LPL compared with LP islets. A significant increase in insulin-induced insulin receptor substrate I associated PI3K activation was also observed in LPL compared with LP islets. These findings indicate that leucine supplementation can augment islet function in malnourished rats and that activation of the PI3K/maminalian target protein of rapamycin pathway may play a role in this process. (C) 2010 Elsevier Inc. All rights reserved.

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Pyroglutamyl proline-rich oligopeptides, present in the venom of the pit viper Bothrops jararaca (Bj-PROs), are the first described naturally occurring inhibitors of the angiotensin I-converting enzyme (ACE). The inhibition of ACE by the decapeptide Bj-PRO-10c (

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Candida albicans is the most common opportunistic fungal pathogen and causes local and systemic disease in immunocompromised patients. Alveolar macrophages (AMs) are pivotal for the clearance of C. albicans from the lung. Activated AMs secrete 5-lipoxygenase-derived leukotrienes (LTs), which in turn enhance phagocytosis and microbicidal activity against a diverse array of pathogens. Our aim was to investigate the role of LTB(4) and LTD(4) in AM antimicrobial functions against C. albicans and the signaling pathways involved. Pharmacologic and genetic inhibition of LT biosynthesis as well as receptor antagonism reduced phagocytosis of C. albicans when compared with untreated or WT controls. Conversely, exogenous LTs of both classes augmented base-line C. albicans phagocytosis by AMs. Although LTB(4) enhanced mainly mannose receptor-dependent fungal ingestion, LTD(4) enhanced mainly dectin-1 receptor-mediated phagocytosis. LT enhancement of yeast ingestion was dependent on protein kinase C-delta (PKC delta) and PI3K but not PKC alpha and MAPK activation. Both LTs reduced activation of cofilin-1, whereas they enhanced total cellular F-actin; however, LTB(4) accomplished this through the activation of LIM kinases (LIMKs) 1 and 2, whereas LTD(4) did so exclusively via LIMK-2. Finally, both exogenous LTB(4) and LTD(4) enhanced AM fungicidal activity in an NADPH oxidase-dependent manner. Our data identify LTB(4) and LTD(4) as key mediators of innate immunity against C. albicans, which act by both distinct and conserved signaling mechanisms to enhance multiple antimicrobial functions of AMs.

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Formaldehyde (FA) exposure induces upper airways irritation and respiratory abnormalities, but its mechanisms are not understood. Since mast cells are widely distributed in the airways, we hypothesized that FA might modify the airways reactivity by mechanism involving their activation. Tracheal rings of rats were incubated with Dulbecco`s modified medium culture containing FA (0.1 ppm) in 96-well plastic microplates in a humid atmosphere. After 30 min, 6 h, and 24-72 h, the rings were suspended in an organ bath and dose-response curve to methacholine (MCh) were determined. incubation with FA caused a transient tracheal hyperresponsiveness to MCh that was independent from tracheal epithelium integrity. Connective tissue mast cell depletion caused by compound 48/80 or mast cell activation by the allergic reaction, before exposure of tracheal rings to FA prevented the increased responsiveness to MCh. LTB(4) concentrations were increased in the culture medium of tracheas incubated with FA for 48 h, whereas the LTB(4)-receptor antagonist MK886 (1 mu M) added before FA exposure rendered the tracheal rings normoreactive to MCh. In addition, FA exposure did not cause hyperresponsiveness in tracheal segments incubated with L-arginine (1 mu M). We suggest that airway connective tissue mast cells constitute the target and may provide the increased LTB(4) generation as well as an elevated consumption of NO leading to tracheal hyperresponsiveness to MCh. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

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Nanostrucured europium oxide and hydroxide films were obtained by pulsed Nd:YAG (532 nm) laser ablation of a europium metallic target, in the presence of a 1 mbar helium buffer atmosphere. Both the produced film and the ambient plasma were characterized. The plasma was monitored by an electrostatic probe, for plume expansion in vacuum or in the presence of the buffer atmosphere. The time evolution of the ion saturation current was obtained for several probe to substrate distances. The results show the splitting of the plume into two velocity groups, being the lower velocity profile associated with metal cluster formation within the plume. The films were obtained in the presence of helium atmosphere, for several target-to-substrate distances. They were analyzed by Rutherford backscattering spectrometry, x-ray diffraction, and atomic force microscopy, for as-deposited and 600 degrees C treated-in-air samples. The results show that the as-deposited samples are amorphous and have chemical composition compatible with europium hydroxide. The thermally treated samples show x-ray diffraction peaks of Eu(2)O(3), with chemical composition showing excess oxygen. Film nanostructuring was shown to be strongly correlated with cluster formation, as shown by velocity splitting in probe current versus time plots. (C) 2010 American Vacuum Society. [DOI: 10.1116/1.3457784]