Experiments on Global and Local Adaptation to Illumination Conditions based on Focal-Plane Average Compuutation

AbstractTwo experiments examined global and local behavioral adaptation effects within and across the Eriksen task, where conflict is based on stimulus letter identities, and the Simon task, where conflict is based on stimulus and response locations. Trials of the two tasks were randomly intermixed, and the list-wide proportion of congruent trials was varied in both tasks (Experiment 1) or in just one task (Experiment 2). The global adaptation effect of list-wide congruency proportion (LWPC effect) was at least as large in the Simon task as in the Eriksen task. Likewise, the local adaptation effect of previous-trial congruency (Gratton effect) was at least as large in the Simon task as in the Eriksen task. In contrast to prior studies investigating transfer across Stroop and Simon tasks, there was no dissociation between global and local adaptation effects regarding their transfer across the different conflict tasks. In fact, both local and global adaptation effects appeared largely task-specific, because there was no or only little transfer of either Gratton effects or LWPC effects from the Eriksen to the Simon task or vice versa. On the whole, the results suggest that behavioral adaptation observed in the present design does not carry over from one of these tasks to the other, suggesting no involvement of a higher-order, task-general mechanism of cognitive control.

Download Full-text

Linking global and local adaptation responses in cities to climate change: An assessment of current practice in Latin America

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1307/6/33/332005 ◽

2009 ◽

Vol 6 (33) ◽

pp. 332005

Author(s):

Dirk Heinrichs ◽

R Jordán Fuchs ◽

J Vogel

Keyword(s):

Climate Change ◽

Latin America ◽

Local Adaptation ◽

Current Practice ◽

Global And Local

Download Full-text

Worldwide population structure, long term demography, and local adaptation of Helicobacter pylori

10.1101/019430 ◽

2015 ◽

Author(s):

Valeria Montano ◽

Xavier Didelot ◽

Matthieu Foll ◽

Bodo Linz ◽

Richard Reinhardt ◽

...

Keyword(s):

Helicobacter Pylori ◽

Population Structure ◽

Local Adaptation ◽

Demographic History ◽

Gastric Diseases ◽

Whole Genome Analysis ◽

Necrosis Factor Alpha ◽

Worldwide Population ◽

H Pylori ◽

Global And Local

Helicobacter pylori is an important human pathogen associated with serious gastric diseases. Owing to its medical importance and close relationship with its human host, understanding genomic patterns of global and local adaptation in H. pylori may be of particular significance for both clinical and evolutionary studies. Here we present the first such whole-genome analysis of 60 globally distributed strains, from which we inferred worldwide population structure and demographic history and shed light on interesting global and local events of positive selection, with particular emphasis on the evolution of San-associated lineages. Our results indicate a more ancient origin for the association of humans and H. pylori than previously thought. We identify several important perspectives for future clinical research on candidate selected regions that include both previously characterized genes (e.g. transcription elongation factor NusA and tumor Necrosis Factor Alpha-Inducing Protein Tipα) and hitherto unknown functional genes.

Download Full-text

Sunspot Groups as Tracers of Sub-Surface Processes

International Astronomical Union Colloquium ◽

10.1017/s0252921100064393 ◽

2000 ◽

Vol 179 ◽

pp. 155-160

Author(s):

M. H. Gokhale

Keyword(s):

Magnetic Flux ◽

Indian Institute ◽

Surface Processes ◽

The Sun ◽

Global And Local ◽

Sunspot Groups

AbstractData on sunspot groups have been quite useful for obtaining clues to several processes on global and local scales within the sun which lead to emergence of toroidal magnetic flux above the sun’s surface. I present here a report on such studies carried out at Indian Institute of Astrophysics during the last decade or so.

Download Full-text

Tandem scanning reflected light microscopy: How it works and applications

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100142104 ◽

1986 ◽

Vol 44 ◽

pp. 84-87

Author(s):

Alan Boyde ◽

Milan Hadravský ◽

Mojmír Petran ◽

Timothy F. Watson ◽

Sheila J. Jones ◽

...

Keyword(s):

Light Microscopy ◽

Focal Plane ◽

Central Symmetry ◽

Single Line ◽

Scanning Microscope ◽

Reflected Light ◽

Illuminating Light ◽

Illuminating Beam

The principles of tandem scanning reflected light microscopy and the design of recent instruments are fully described elsewhere and here only briefly. The illuminating light is intercepted by a rotating aperture disc which lies in the intermediate focal plane of a standard LM objective. This device provides an array of separate scanning beams which light up corresponding patches in the plane of focus more intensely than out of focus layers. Reflected light from these patches is imaged on to a matching array of apertures on the opposite side of the same aperture disc and which are scanning in the focal plane of the eyepiece. An arrangement of mirrors converts the central symmetry of the disc into congruency, so that the array of apertures which chop the illuminating beam is identical with the array on the observation side. Thus both illumination and “detection” are scanned in tandem, giving rise to the name Tandem Scanning Microscope (TSM). The apertures are arranged on Archimedean spirals: each opposed pair scans a single line in the image.

Download Full-text

Imaging sub-micron objects with light microscopy: Visualization of the T-4 bacteriophage

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100156158 ◽

1989 ◽

Vol 47 ◽

pp. 834-835

Author(s):

Malcolm Brown ◽

Reynolds M. Delgado ◽

Michael J. Fink

Keyword(s):

Electron Microscopy ◽

Light Microscopy ◽

Focal Plane ◽

Phase Contrast ◽

Dark Field ◽

E Coli ◽

Polystyrene Beads ◽

Television Camera ◽

Transmission Electron ◽

Universal Microscope

While light microscopy has been used to image sub-micron objects, numerous problems with diffraction-limitations often preclude extraction of useful information. Using conventional dark-field and phase contrast light microscopy coupled with image processing, we have studied the following objects: (a) polystyrene beads (88nm, 264nm, and 557mn); (b) frustules of the diatom, Pleurosigma angulatum, and the T-4 bacteriophage attached to its host, E. coli or free in the medium. Equivalent images of the same areas of polystyrene beads and T-4 bacteriophages were produced using transmission electron microscopy.For light microscopy, we used a Zeiss universal microscope. For phase contrast observations a 100X Neofluar objective (N.A.=1.3) was applied. With dark-field, a 100X planachromat objective (N.A.=1.25) in combination with an ultra-condenser (N.A.=1.25) was employed. An intermediate magnifier (Optivar) was available to conveniently give magnification settings of 1.25, 1.6, and 2.0. The image was projected onto the back focal plane of a film or television camera with a Carl Zeiss Jena 18X Compens ocular.

Download Full-text

Microspectroscopy Using a Solid Immersion Lens

Microscopy and Microanalysis ◽

10.1017/s1431927600026817 ◽

2001 ◽

Vol 7 (S2) ◽

pp. 148-149

Author(s):

C.D. Poweleit ◽

J Menéndez

Keyword(s):

Spatial Resolution ◽

Focal Plane ◽

Numerical Aperture ◽

Normal Incidence ◽

Spot Size ◽

Index Of Refraction ◽

Objective Lens ◽

Improvement Factor ◽

Oil Immersion ◽

Long Time

Oil immersion lenses have been used in optical microscopy for a long time. The light’s wavelength is decreased by the oil’s index of refraction n and this reduces the minimum spot size. Additionally, the oil medium allows a larger collection angle, thereby increasing the numerical aperture. The SIL is based on the same principle, but offers more flexibility because the higher index material is solid. in particular, SILs can be deployed in cryogenic environments. Using a hemispherical glass the spatial resolution is improved by a factor n with respect to the resolution obtained with the microscope’s objective lens alone. The improvement factor is equal to n2 for truncated spheres.As shown in Fig. 1, the hemisphere SIL is in contact with the sample and does not affect the position of the focal plane. The focused rays from the objective strike the lens at normal incidence, so that no refraction takes place.

Download Full-text