scholarly journals DARK ADAPTATION IN AGRIOLIMAX

1928 ◽  
Vol 12 (1) ◽  
pp. 83-109 ◽  
Author(s):  
W. J. Crozier ◽  
Ernst Wolf
Keyword(s):  
Dark Adaptation ◽  
Light Adaptation ◽  
The Body ◽  
Differential Sensitivity ◽  
Different Types ◽  
The Difference ◽  
Two Sides ◽  
Kinetics Of ◽  
Different Levels ◽  
Continuous Excitation

A method is described which measures the excitation of Agriolimax by light, during the progress of light adaptation, by assuming that the orientating effect of continuous excitation is expressed as a directly proportionate tension difference in the orienting muscles of the two sides of the body. The tendency toward establishment of such a tension difference is caused to work against a similar geotropic effect at right angles to the phototropic one. This enables one to study the kinetics of light adaptation, and of dark adaptation as well. The situation in the receptors is adequately described by the paradigm See PDF for Equation similar to that derived by Hecht for the differential sensitivity of various forms, but with the difference that the "dark" reaction is not only "bimolecular" but also autocatalysed by the reaction product S. The progress of dark adaptation is reflected (1) in the recovery of the amplitude of the orientation and (2) in the rates of light adaptation at different levels of the recovery; each independently supports these assumptions, for which the necessary equations have been provided. These equations also account for the relative variabilities of the angles of orientation, and, more significantly, for the two quite different kinds of curves of dark adaptation which are obtained in slightly different types of tests.

scholarly journals LOGICAL REASONING ANALYSIS BASED ON HIPPOCRATES PERSONALITY TYPES

Aksioma ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 57-73
Author(s):  
Nurdin Nurdin ◽  
Ita Sarmita Samad ◽  
Sardia Sardia
Keyword(s):  
Problem Solving ◽  
Mathematical Problem ◽  
Logical Reasoning ◽  
Personality Types ◽  
The Body ◽  
Mathematical Problem Solving ◽  
Different Types ◽  
Ways Of Thinking ◽  
The Difference ◽  
Descriptive Qualitative

Abstract: The theory distinguishes human based on four different personality types such as: sanguine, choleric, melancholic, and phlegmatic. Different types of personality caused by differences in the dominant fluid in the body. These differences will result in terms of behavior, ways of thinking and to get along. The type of this research that is descriptive qualitative which it is describing the logical reasoning based on Hippocrates personality types. The logical reasoning is analyzed through the four types of personality in relation to mathematical problem solving. The Analysis is done based on the logical reasoning indicator/ subindicator and the steps of problem solving stated by Polya. The result shows that there is a reasoning difference on each type of personalities. The difference can be terms of the strenght or the weakness. Sanguine is quicker in understanding problems and communicating results, choleric is more accelerated in work, melancholic is more perfect at work, and  phlegmatic is superior in terms of accuracy. Keywords: Logical reasoning, Hippocrates, sanguine, choleric, melancholic, phlegmatic

scholarly journals THE CULTIVATION OF TRICHOMONAS OF THE HUMAN MOUTH (TETRATRICHOMONAS HOMINIS)

1917 ◽  
Vol 25 (2) ◽  
pp. 341-347 ◽  
Author(s):  
Tokuzo Ohira ◽  
Hideyo Noguchi
Keyword(s):  
Cultural Studies ◽  
Cell Body ◽  
Trichomonas Vaginalis ◽  
The Body ◽  
The Other ◽  
Other Hand ◽  
Deep Groove ◽  
Different Types ◽  
The Difference

Trichomonades from the mouth were studied by Steinberg who proposed to group them into three distinct types; namely, Trichomonas elongata, Trichomonas caudata, and Trichomonas flagellata. Doflein (3) regards them as probably identical with Trichomonas hominis. Opinions differ as to whether or not Trichomonas vaginalis Donné and Trichomonas hominis Grassi are the same species. Lynch, for instance, believes that they are the same species, while von Prowazek (4), Bensen (5), and others (6, 7) insist that they are different types. Bensen's view seems to be well supported by the difference alleged to be found between the mode of encystment in the two trichomonades, were it not for the fact that our knowledge about the so called cyst of trichomonades is still obscure. According to Alexeieff (8) many of the so called cysts were evidently blastomyces contained in the cell body of the trichomonas. An autogamy alleged to take place in cysts as described by Bohne and von Prowazek (9) has not been confirmed by Dobell (10). And Wenyon (11) contends that it has never been found possible to produce any development of these cysts outside the body on the warm stage as can be done with the cysts of Entamœba coli. Therefore, it is still premature to take the process of encystment into consideration as far as the classification of trichomonas is concerned. On the other hand, Rodenwaldt (12) seems to think that there are many species of trichomonas in the human intestines, and Wenyon has described a new trichomonas from the human intestines (Macrostoma mesnili Wenyon). Further cultural studies in the morphology and biology of these organisms must be carried out in order to solve these problems. In the light of modern investigations there are five subgenera to be included under the genus Trichomonas Donné. They are as follows: (1) Protrichomonas Alexeieff, with three anterior flagella, without an undulating membrane. (2) Trichomastix Biitschli) with three anterior flagella and a trailing flagellum (Schleppgeissel) without an undulating membrane. (3) Trichomonas Donné, with three anterior flagella and an undulating membrane. (4) Macrostoma Alexeieff, Amend, Wenyon (11), with three anterior flagella and an undulating membrane wedged in a deep groove (peristome). (5) Tetratrichomonas Parisi (13), with four anterior flagella and an undulating membrane. As far as our culture trichomonas from the human mouth is concerned, it has been shown that it is not strictly a trichomonas and that it should be classed under the subgenus Tetratrichomonas.

scholarly journals DARK ADAPTATION AND THE LIGHT-GROWTH RESPONSE OF PHYCOMYCES

1929 ◽  
Vol 12 (3) ◽  
pp. 391-400 ◽  
Author(s):  
E. S. Castle
Keyword(s):  
Latent Period ◽  
Dark Adaptation ◽  
Growth Response ◽  
Light Adaptation ◽  
Exposure Period ◽  
Bimolecular Reaction ◽  
Dark Reaction ◽  
Action Time ◽  
Kinetics Of ◽  
Photochemical Action

1. A single-celled, elongating sporangiophore of Phycomyces responds to a sufficient increase in intensity of illumination by a brief increase in growth rate. This is the "light-growth response" of Blaauw. 2. The reaction time is compound, consisting of an exposure period and a latent period (this comprising both the true latent period resulting from photochemical action and any "action time" necessary for the response). During the latter period the plant may be in darkness, responding nevertheless at the end of the latent period. 3. Both light adaptation and dark adaptation occur in the sporangiophore. The kinetics of dark adaptation can be accounted for on the basis of a bimolecular reaction, perhaps modified by autocatalysis. Attention is called to the bimolecular nature of the "dark" reaction in all other photosensory systems that have been studied, in spite of the diversity of the photosensitive substances themselves and of the different forms of the responses to light.

Adaptation in the Compound Eye and Interaction with Screening Pigment

1972 ◽  
Vol 56 (1) ◽  
pp. 119-128
Author(s):  
U. YINON
Keyword(s):  
Dark Adaptation ◽  
Light Adaptation ◽  
Compound Eye ◽  
Electrical Response ◽  
Negative Potential ◽  
Neural Pathways ◽  
Photochemical Process ◽  
Screening Pigment ◽  
The Difference ◽  
Adaptation Processes

The electroretinogram pattern in the compound eye of T. molitor and the appearance of irregular small potentials and spikes superimposed on the ERG are influenced during dark and light adaptation procedures. The amplitude of the principal negative potential reflects bleaching and recovery of the photochemical process. This is not true for the latency values. The delay of the electrical response increases in the dark and decreases in the light adapted eye. These changes were influenced by the intensity of the adapting light. Mutant eyes only lack screening pigment and have normal visual neural pathways. The absence of this pigment lowered the threshold sensitivity of the unscreened eye in dark adaptation. The difference between the adaptation processes in mutants and normal animals has been suggested as a criterion for measuring the net effect of the screening pigment in the compound eye.

Residual Stress in Ferrite and Austenite after Rolling and Recovery Processes

2013 ◽  
Vol 772 ◽  
pp. 79-83
Author(s):  
Krzysztof Wierzbanowski ◽  
Andrzej Baczmanski ◽  
Roman Wawszczak ◽  
Marcin Wronski ◽  
Mirosław Wróbel ◽  
...  
Keyword(s):  
Residual Stresses ◽  
Orientation Distribution ◽  
Reflection Method ◽  
Stress Variation ◽  
X Ray ◽  
Recovery Processes ◽  
Different Types ◽  
Kinetics Of ◽  
Different Levels ◽  
Diffraction Peak Width

The relation between residual stresses occurring in plastically deformed material and after subsequent annealing is of practical and theoretical importance. In the present work the X-ray multi-reflection method was applied to determine residual stresses and their orientation distribution in rolled and annealed ferrite and austenite steel samples. An important decrease of the first- and the second-order residual stresses was observed during recovery and recrystallization processes. Diffraction peak width was also studied and correlated with stress variation during annealing. Different kinetics of stress relaxation in ferrite and austenite were explained by different levels of stacking fault energy and different types of intergranular interactions occurring in these materials.

A Comparison of the Biology of Echinus esculentus in Different Habitats

1934 ◽  
Vol 19 (2) ◽  
pp. 869-885 ◽  
Author(s):  
Hilary B. Moore
Keyword(s):  
Environmental Conditions ◽  
Maximum Size ◽  
The Body ◽  
Maximum Volume ◽  
Food Material ◽  
Characteristic Type ◽  
Different Types ◽  
The Difference ◽  
The One ◽  
Reserve Food

There are two types of ground at Port Erin, differing widely in the general environmental conditions, and each with a characteristic type of urchin on it. The difference is sufficiently well marked for the local fishermen, who collect the urchins for sale to summer visitors, to distinguish them as different types. The littoral urchins from the Breakwater are larger and thicker shelled than those from the Breast. Their gonads reach a greater maximum size, and, in fact, never fall as low even as the maximum volume for the Breast urchin gonads. This difference is probably correlated with the much greater food supply on the Breakwater, since the gonad is the one organ of the body in which the animal can store reserve food material. Spawning commences in March or April and lasts for about two months, but is slightly earlier on the Breakwater than on the Breast. Ripening also takes place considerably earlier in both sexes on the littoral ground. Spawning seems to set in at a temperature of about 7° C., and the colder winter of 1931, compared with 1932, was associated with a later ripening and spawning, i n the former year. Similarly it is suggested that the slightly later spawning on the Breast than on the Breakwater is correlated with the slightly later rise in the temperature of the water on the deeper water ground in the spring.

scholarly journals Dark-adapted rod suppression of cone flicker detection: Evaluation of receptoral and postreceptoral interactions

2006 ◽  
Vol 23 (3-4) ◽  
pp. 531-537 ◽  
Author(s):  
DINGCAI CAO ◽  
ANDREW J. ZELE ◽  
JOEL POKORNY
Keyword(s):  
Dark Adaptation ◽  
Light Adaptation ◽  
Central Field ◽  
Magnocellular Pathway ◽  
Stimulus Field ◽  
Independent Control ◽  
Detection Evaluation ◽  
Different Levels

Dark-adapted rods in the area surrounding a luminance-modulated field can suppress flicker detection. However, the characteristics of the interaction between rods and each of the cone types are unclear. To address this issue, the effect that dark-adapted rods have on specific classes of receptoral and postreceptoral signals was determined by measuring the critical fusion frequencies (CFF) for receptoral L-, M-, and S-cone and postreceptoral luminance ([L+M+S] and [L+M+S+Rod]) and chromatic ([L/(L+M)]) signals in the presence of different levels of surrounding rod activity. Stimuli were generated with a two-channel photostimulator that has four primaries for a central field and four primaries for the surround, allowing independent control of rod and cone excitation. Measurements were made either with adaptation to the stimulus field after dark adaptation or during a brief period following light adaptation. The results show that dark-adapted rods maximally suppressed the CFF by ∼6 Hz for L-cone, M-cone, and luminance modulation. Dark-adapted rods, however, did not significantly alter the S-cone CFF. The [L/(L+M)] postreceptoral CFF was slightly suppressed at higher surround illuminances, that is, higher than surround luminances resulting in suppression for L-cone, M-cone, or luminance modulation. We conclude that rod-cone interactions in flicker detection occurred strongly in the magnocellular pathway.

scholarly journals Steps of Designing a Personal Questions Bank in a Pedagogical Way

2020 ◽  
Vol 10 (6) ◽  
pp. 638
Author(s):  
Mona M. Hamad ◽  
Ehab S. Alnuzaili
Keyword(s):  
Learning Outcomes ◽  
Bloom's Taxonomy ◽  
Cognitive Domain ◽  
Whole Process ◽  
Bloom’S Taxonomy ◽  
Complicated Process ◽  
Different Types ◽  
The Difference ◽  
Intended Learning Outcomes ◽  
Different Levels

Teaching is one of the most important professions that affect different aspects of life. Despite the difference between teaching and testing process, they have a huge interdependent and integrated relation. Teasing information out of them is a complicated process when they are separated. The educational objectives can’t be achieved without the integration between teaching and testing .This paper addresses steps of designing a questions bank that may help teachers come out with perfect tests that evaluate different levels of Bloom’s Taxonomy cognitive domain, backwash the whole process of the course learning, and reflect intended learning outcomes (ILOs). This paper helps teachers design their questions bank while they are teaching and illustrates steps of feeding it with different types of questions using the cognitive domain of Bloom’s Taxonomy, table of specification (TOS) and level of difficulties in a pedagogical way.

scholarly journals Impact of a freeway on the dispersal of ticks and Ixodes ricinus-borne pathogens: forested resting areas may become Lyme disease hotspots

2017 ◽  
Vol 65 (2) ◽  
pp. 242-252 ◽  
Author(s):  
Sándor Hornok ◽  
Maria Mulvihill ◽  
Krisztina Szőke ◽  
Enikő Gönczi ◽  
Kinga M. Sulyok ◽  
...  
Keyword(s):  
Lyme Disease ◽  
Ixodes Ricinus ◽  
Tick Species ◽  
Dermacentor Reticulatus ◽  
Ixodid Ticks ◽  
Significant Difference ◽  
Different Types ◽  
Pathogen Prevalence ◽  
The Difference ◽  
Two Sides

Man-made barriers are well known for their effects on ecosystems. Habitat fragmentation, for instance, is a recognised consequence of modern-day infrastructure. The aim of the present study was to investigate the diversity and abundance of tick species, as well as the risks of acquiring tick-borne infections in habitats adjacent to a freeway. Therefore, ixodid ticks were collected from the vegetation at two-week intervals (in the main tick season, from March to June) in eight habitats of different types (forest, grove, grassland) along both sides of a freeway. Ixodes ricinus females were molecularly screened for three species of tick-borne bacteria. In the study period, 887 ixodid ticks were collected. These included 704 I. ricinus (79.4%), 51 Dermacentor reticulatus (5.7%), 78 D. marginatus (8.8%), 35 Haemaphysalis inermis (3.9%) and 19 H. concinna (2.1%). There was no significant difference in the abundance of tick species between similar habitats separated by the freeway, except for the absence of Dermacentor spp. on one side. In I. ricinus females, the overall prevalence of Anaplasma phagocytophilum was low, and (in part due to this low rate) did not show significant difference between the two sides of the freeway. Rickettsia helvetica had significantly different overall prevalence between two distant habitats along the same side of the freeway (12.3% vs. 31.4%), but not between habitats on the opposite sides. Borrelia burgdorferi s.l. showed significantly different overall prevalence between habitats both on the same and on the opposite sides of the freeway (8.6–35.9%), and the difference was higher if relevant habitats were also separated by the freeway. Importantly, the prevalence rate of the Lyme disease agent was highest in a forested resting area of the freeway, and was significantly inversely proportional to the prevalence of A. phagocytophilum (taking into account all evaluated habitats), apparently related to deer population density. Prevalence rates of these bacteria also differed significantly on single sampling occasions between: (1) closely situated habitats of different types; (2) distant and either similar or different habitat types; and (3) habitats on the opposite sides of the freeway. In conclusion, the findings of the present study show that a fenced freeway may contribute to differences in tick species diversity and tick-borne pathogen prevalence along its two sides, and this effect is most likely a consequence of its barrier role preventing deer movements.

scholarly journals The Duplex Nature of the Retina of the Nocturnal Gecko as Reflected in the Electroretinogram

1961 ◽  
Vol 44 (6) ◽  
pp. 1143-1158 ◽  
Author(s):  
Eberhard Dodt ◽  
Karl Heinz Jessen
Keyword(s):  
Electrical Activity ◽  
Dark Adaptation ◽  
Light Adaptation ◽  
Slow Phase ◽  
Strong Light ◽  
Increment Threshold ◽  
Hemidactylus Turcicus ◽  
Low Levels ◽  
Different Levels ◽  
Effect Of Light

The effect of light and dark adaptation on the electrical activity in two species of nocturnal gecko, Hemidactylus turcicus and Tarentola mauritanica was studied. The electroretinogram of both species changes from the scotopic type in the dark-adapted state to the photopic type after strong light adaptation. For the scotopic response fusion frequencies up to 18 flashes per sec. are obtained in both species. For the photopic response fusion frequencies up to 50 flashes per sec. are seen in Tarentola, and up to 25 flashes per sec. in Hemidactylus. Proceeding from dark to light adaptation the increment threshold (dI) is measured at different levels of adaptive illumination (I). At low levels of illumination the dI/I ratio is found to be small and at high levels of illumination to be large. No difference in the dI/I ratio is obtained for test lights of 462 and 605 mµ. During dark adaptation the change of threshold after exposure to moderate and weak lights (up to 103 times dark threshold) is rather fast. After light adaptation to strong light (106 times dark threshold) duplex dark adaptation curves are seen with a break separating a fast and a slow phase of dark adaptation. The significance of these results from a retina which possesses sense cells of only one type is discussed.

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