19,761 research outputs found
Osmotic regulation of alpha-amylase synthesis and polyribosome formation in aleurone cells of barley.
Water stress inhibits the gibberellic acid (GA(3))-induced synthesis of alpha-amylase in aleurone layers of barley (Hordeum vulgare L.). Electron microscope evidence indicates that the effect of water stress induced by 0.6 M solutions of polyethylene glycol (PEG) is to reduce the binding of ribosomes to the endoplasmic reticulum. This was confirmed by sucrose density gradient centrifugation of polyribosome preparations from stressed cells. The reduction in polyribosome formation does not result from reduced ribosome activity as measured by [(3)H]peptidylpuromycin formation. Thus, calculation of percent active ribosomes shows that osmoticum has little effect on the ability of ribosomes to incorporate puromycin into nascent protein. Water stress does not cause a marked decrease in the total RNA level of aleurone cells. Estimates of total RNA in postmitochondrial supernatant fractions from stressed cells show only a reduction of 8-9% relative to the control. Membrane synthesis measured by [(14)C]choline incorporation is depressed by 15% in cells stressed with 0.6 M PEG for 2.5 hours
Simulator comparison of thumball, thumb switch, and touch screen input concepts for interaction with a large screen cockpit display format
A piloted simulation study was conducted comparing three different input methods for interfacing to a large screen, multiwindow, whole flight deck display for management of transport aircraft systems. The thumball concept utilized a miniature trackball embedded in a conventional side arm controller. The multifunction control throttle and stick (MCTAS) concept employed a thumb switch located in the throttle handle. The touch screen concept provided data entry through a capacitive touch screen installed on the display surface. The objective and subjective results obtained indicate that, with present implementations, the thumball concept was the most appropriate for interfacing with aircraft systems/subsystems presented on a large screen display. Not unexpectedly, the completion time differences between the three concepts varied with the task being performed, although the thumball implementation consistently outperformed the other two concepts. However, pilot suggestions for improved implementations of the MCTAS and touch screen concepts could reduce some of these differences
340 years of atmospheric circulation characteristics reconstructed from an eastern Antarctic Peninsula ice core
Copyright @ 2006 American Geophysical Union (AGU)Precipitation delivery mechanisms for Dolleman Island (DI), located off the east coast of the Antarctic Peninsula, are investigated using reanalysis and back trajectory data. The Southern Annular Mode (SAM) and ENSO are both shown to influence precipitation delivery and event size. Precipitation delivery variability is compared against the interannual variation of chemical data from two DI ice cores. Nitrate concentration in the cores is strongly linked with the ratio of easterly to westerly back trajectories arriving at DI, as described by a Cross-Peninsula Index (CPI) defined in this paper. This CPI is used subsequently to reconstruct the atmospheric circulation characteristics for the 340-year ice core record. The analysis highlights a period of increased easterlies during 1720â1780 and an increase in westerlies for 1950â1980, the latter concomitant with a positive SAM trend and western Peninsula warming. The reconstruction also reveals periods when polynyas may have been present in the Weddell Sea
A Role for Contrast Gain Control in Skin Appearance
Apparent contrast can be suppressed or enhanced when presented within surrounding images. This contextual modulation is typically accounted for with models of contrast gain control. Similarly, the appearance of one part of a face is affected by the appearance of the other parts of the face. These influences are typically accounted for with models of face-specific holistic processing. Here we report evidence that facial skin appearance is modulated by adjacent surfaces. In four experiments we measured the appearance of skin evenness and wrinkles in images with increased or decreased contrast between facial skin and adjacent image regions. Increased contrast with adjacent regions made facial skin appear more even and less wrinkled. We found the effect whether faces were presented upright or inverted, and also when facial features were not present, ruling out face-specific holistic processing as an explanation yet fully consistent with contrast gain control. Because the mechanism is not face specific, contrast between skin and any adjacent surface should affect skin appearance. This suggests that adornments such as makeup, hair coloring, clothing, and jewelry could also affect skin appearance through contrast suppression or enhancement, linking these cultural practices to the structure and function of the visual system
Computer Error: Voices and Translations in Edwin Morganâs Science Fiction Poetry
My favourite scene in the movie Independence Day (1996) is when Captain Steven Hiller (Will Smith) knocks out an alien with a single clout, whips out a smart âwelcome to Earthâ-esque punch line and then lights up a cigar. Sheer. Smith. Action. But what if aliens arenât all doomsayers, what if all they want is a nice chat? This article will examine the variety of voices in Edwin Morganâs Science Fiction Poetry (hereby referred to as SFP) and consider their continuities and differences with Morganâs non-SFP. It will discuss the importance of Morgan as a translator and experimenter of language, highlighting the freedom which SFP allows Morgan as a poet.
Comparing Antonovsky's sense of coherence scale across three UK post-industrial cities
Objectives: High levels of âexcessâ mortality (ie, that seemingly not explained by deprivation) have been shown for Scotland compared to England and Wales and, especially, for its largest city, Glasgow, compared to the similarly deprived English cities of Liverpool and Manchester. It has been suggested that this excess may be related to differences in âSense of Coherenceâ (SoC) between the populations. The aim of this study was to ascertain whether levels of SoC differed between these cities and whether, therefore, this could be a plausible explanation for the âexcessâ.
Setting: Three post-industrial UK cities: Glasgow, Liverpool and Manchester.
Participants: A representative sample of more than 3700 adults (over 1200 in each city).
Primary and secondary outcome measures: SoC was measured using Antonovsky's 13-item scale (SOC-13). Multivariate linear regression was used to compare SoC between the cities while controlling for characteristics (age, gender, SES etc) of the samples. Additional modelling explored whether differences in SoC moderated city differences in levels of self-assessed health (SAH).
Results: SoC was higher, not lower, among the Glasgow sample. Fully adjusted mean SoC scores for residents of Liverpool and Manchester were, respectively, 5.1 (â5.1 (95% CI â6.0 to â4.1)) and 8.1 (â8.1 (â9.1 to â7.2)) lower than those in Glasgow. The additional modelling confirmed the relationship between SoC and SAH: a 1 unit increase in SoC predicted approximately 3% lower likelihood of reporting bad/very bad health (OR=0.97 (95% CI 0.96 to 0.98)): given the slightly worse SAH in Glasgow, this resulted in slightly lower odds of reporting bad/very bad health for the Liverpool and Manchester samples compared to Glasgow.
Conclusions: The reasons for the high levels of âexcessâ mortality seen in Scotland and particularly Glasgow remain unclear. However, on the basis of these analyses, it appears unlikely that a low SoC provides any explanation
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Felix Socrates?
I argue that Socrates, by his own lights, failed to achieve happiness. This result is important not so much for what it reveals about Socratesâ own well-being, but for what it reveals about the Socratic conception of happiness.Philosoph
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