SOME ASPECTS OF THE ELONGATION OF FUSIFORM CAMBIAL CELLS IN THUJA OCCIDENTALS L.

1956 ◽  
Vol 34 (1) ◽  
pp. 175-196 ◽  
Author(s):  
M. W. Bannan
Keyword(s):  
Tip Growth ◽  
Local Environment ◽  
Growth Cycle ◽  
Minor Role ◽  
Mature Trees ◽  
Neighboring Cell ◽  
Fusiform Initials ◽  
Cambial Cells ◽  
A Minor ◽  
High Degree

An outstanding feature of the elongation of fusiform initials is the high degree of variability that exists from cell to cell. This individual inconstancy is to some extent related to recurrent alterations in the local environment. Thus loss of a neighboring cell often results in accelerated elongation. Although frequently masked by the deviations in individual cells, certain general trends of growth become apparent on analysts of the data from numerous cells. In the growth cycle between successive multiplicative divisions the progress of elongation is not uniform but rather follows a familiar growth pattern, early rapid extension giving way to a gradually decreasing rate of elongation as lengthening proceeds. Growth at opposite ends of the same cell is usually dissimilar, basipetal extension tending to predominate. This bipolar difference is evident in the stems of small trees, in the periphery of the stems of mature trees, in the distal parts of branches, and to a lesser degree, in the proximal parts of recurved branches. The reduced bipolar difference in the inverted proximal portions of recurved branches indicates that gravity is not the major factor in the establishment of polarity, but does perhaps play a minor role. Cell elongation is apparently achieved by tip growth.

SPIRAL GRAIN AND ANTICLINAL DIVISIONS IN THE CAMBIUM OF CONIFERS

1966 ◽  
Vol 44 (11) ◽  
pp. 1515-1538 ◽  
Author(s):  
M. W. Bannan
Keyword(s):  
High Ratio ◽  
Contributory Factor ◽  
Relative Duration ◽  
Mature Trees ◽  
Spiral Grain ◽  
Anticlinal Division ◽  
Fusiform Initials ◽  
The Mean ◽  
Cambial Cells ◽  
The Right

In the cambium of mature trees a general conformity was found in the orientation of the partition in the pseudotransverse division of fusiform initials through out sectors of varying size. The proportion of divisions deviating from the preferred orientation varied with the tree, the locality, and the species, but was usually less than 10%. As radial accretion followed, periodic reversals occurred in the orientation of anticlinal divisions, the spacing between reversals, in terms of xylem increment, being related to the frequency of anticlinal division. The mean interval shortened as the rate of division rose according to the equation xy = k. While this overall relationship obtained, there was generally some inequality in the relative duration of leftward and rightward orientations of division. In species with grain in the outer wood slanted to the right, a rightward tilt of division persisted for longer periods than a leftward tilt. Conversely, in species with grain slanted to the left, thickness of xylem showing leftward orientation of multiplicative divisions exceeded that with rightward orientation. Changes associated with growth from sapling to adult were studied in Picea, in which genus grain is usually to the left in the inner wood and to the right in the outer wood. Here multiplicative divisions were usually inclined to the left in the growth of the first few years, whereas in the later growth orientation to the right endured for longer periods than to the left. Both orientation of pseudo-transverse division and direction of cell elongation after division seem to be under a general polar control. This apparently is an important element in the induction of spiral grain. Above-average net gain of fusiform initials in the turmoil of cell addition and loss, which accompanies circumferential expansion, may be a contributory factor. Serving to restrain the development of an excessive spirality are periodic reversals in direction of tilt in anticlinal division, and a high ratio of loss of cambial cells relative to the frequency of anticlinal division.

scholarly journals Degree of realism (Fiction)

10.34778/3c ◽  
2021 ◽  
Author(s):  
Cordula Nitsch
Keyword(s):  
Real Life ◽  
Minor Role ◽  
The West ◽  
Lord Of The Rings ◽  
Low Degree ◽  
Depiction Of Politics ◽  
A Minor ◽  
High Degree ◽  
Political Actions

The variable tries to capture the degree of realism of the fictional entertainment format. It was used in a systematization of TV series and movies that aimed to structure the field with regard to politics in fictional entertainment (Eilders & Nitsch, 2014, 2015; Nitsch & Eilders, 2014).   Field of application/theoretical foundation The perceived degree of realism is usually considered in effect studies (as a moderating variable). However, it can also be applied to the fictional content and helps differentiating the innumerable fictional productions. It might be assumed that fictional entertainment formats with many references to social reality elicit other effects than TV series and movies that do not include aspects that are familiar to the audience from real-life.   References/combination with other methods of data collection ---   Example study Eilders & Nitsch (2015)   Information on Eilders & Nitsch, 2015 Authors:                                Christiane Eilders & Cordula Nitsch Research interest:                depiction of politics (centrality of politics, topics, actors, political actions) in political dramas of two different countries (US and Germany) Object of analysis:                114 movies and 98 TV-series Timeframe of analysis:        1990-2013   Information about variable Variable name/definition:   degree of realism Degree of realism is indicated through four variables: 1) realism in terms of events, 2) in terms of characters, 3) in terms of time, and 4) in terms of places. Every indicator was coded on a scale ranging from 0 (no realism at all) to 3 (high degree of realism). Realism in terms of events regards the degree to which the plot refers to real-life events (e.g., historical references, bank holidays). Realism of characters captures whether real actors or institutions are addressed in the plot. It was coded whether real characters played no role (0), a marginal role (1), a minor role (2), or a major role (3) in the TV series or movie. Realism in terms of time measures the time between the year of production and the year in which the fictional plot takes place. 0 was coded for plots located in periods deviating by more than 50 years from the production year, plots located in periods not overtly deviating from the production year were coded 3. Realism of places captures whether places are clearly identifiable. The highest score refers to plots that take place at particular locations on Earth, plots that take place in completely fictitious locations (such as Middle Earth in The Lord of the Rings) received the lowest score. Level of analysis:      Film- bzw. Serienebene [level of movies/series] Scale level:                Nominal Reliability:                .87 (realism in terms of time: 1.0, realism in terms of places: 0.9, realism in terms of events: 0.86 and realism in terms of characters: 0.71)   V 1 Degree of Realism V1.3 Realitätsnähe der Zeit (RZ) (Bezugspunkt: Plot) [Realism in terms of time (RT) [Reference point: plot]] Unter RZ wird codiert, wie weit das Produktionsjahr des Films/der Serie von der Zeit abweicht, die im Film/der Serie dargestellt wird. Es wird angenommen, dass Filme/Serien, die in der Vergangenheit oder Zukunft spielen, eine geringere Realitätsnähe haben. Filme/Serien, die in anderen Welten mit eigenen Zeitlinien spielen, sind ebenfalls nicht realitätsnah. Bei Filmen/Serien, die über längere Zeiträume hinweg spielen, wird das Jahr, in dem der größte Teil der Handlung spielt, herangezogen. Sollte dies nicht erkennbar sein, ist das früheste Jahr, das vorkommt, das Referenzjahr. [For RT it is coded how far the production year of the movie/series deviates from the time the movie/series is set in. It is assumed that movies/series which are set in the past or future are less close to (the viewers’) reality. Movies/series that play in other worlds with their own timelines are also considered to have a low degree of realism. For movies/series that cover longer periods of time, the year in which most of the plot takes place is used. Should this not be recognizable, the earliest year the plot is set in, is used as the reference year.]   0 = Keine Realitätsnähe Der Film/Serie spielt entweder in einem Jahr, das mehr als 50 Jahre (plus/minus) vom Produktionsjahr des Films/Serie abweicht oder in einer Welt mit anderer Zeitrechnung. Beispiel: „Braveheart“ als Film, der im Mittelalter spielt und somit mehr als 50 Jahre vom Produktionsjahr 1995 abweicht.   1 = Geringe Realitätsnähe Der Film/Serie spielt in einem Jahr, das zwischen 50 und 11 Jahren (plus/minus) vom Produktionsjahr des Films/Serie abweicht. Beispiel: „Das Leben der Anderen“ als Film, der 1984 spielt und somit 22 Jahre vom Produktionsjahr 2006 abweicht.   2 = Mittlere Realitätsnähe Der Film/Serie spielt in einem Jahr, das vom Produktionsjahr maximal 10 Jahre (plus/minus) abweicht. Beispiel: „Hotel Ruanda“ als Film, der 2004 gedreht wurde und im Jahr 1994 spielt.   3 = Hohe Realitätsnähe Der Film/Serie spielt in einem Jahr, das vom Produktionsjahr durch keine sichtbare Verweise auf eine andere Zeit abweicht. Beispiel: „Keinohrhasen“ als Film, in dem es keine erkennbare Abweichung von Produktionsjahr und der dargestellten Zeit gibt.    References Eilders, C., & Nitsch, C. (2014). Politikvermittlung zwischen „Traumschiff“ und „The West Wing“: Ein Vorschlag zur Systematisierung von Fernsehserien [Political depictions between „Traumschiff“ and „The West Wing“: A proposal for a systematization of TV series]. In M. Dohle & G. Vowe (Hrsg.), Politische Unterhaltung – Unterhaltende Politik. Forschung zu Medieninhalten, Medienrezeption und Medienwirkungen (S. 138–162). Köln: Herbert von Halem. Eilders, C., & Nitsch, C. (2015). Politics in Fictional Entertainment: An Empirical Classification of Movies and TV Series. International Journal of Communication, 9, 1563–1587. Nitsch, C. & Eilders, C. (2014). Die Repräsentation von Politik in fiktionaler Unterhaltung. Instrument, Anwendung und Befunde zur Systematisierung von Filmen und Fernsehserien [The representation of politics in fictional entertainment. Instrument, application and results for a systematization of films and TV series]. Studies in Communication | Media, 3(1), S. 120–143.

THE RATE OF ELONGATION OF FUSIFORM INITIALS IN THE CAMBIUM OF PINACEAE

1965 ◽  
Vol 43 (4) ◽  
pp. 429-435 ◽  
Author(s):  
M. W. Bannan
Keyword(s):  
Cell Elongation ◽  
Radial Growth ◽  
Ring Width ◽  
Total Width ◽  
Mature Trees ◽  
Cambial Cell ◽  
Anticlinal Division ◽  
Fusiform Initials ◽  
Wide Ring ◽  
Cambial Cells

This report deals with the rate and amount of elongation of fusiform initials in the cycle of cell elongation and multiplication by pseudotransverse division which accompanies circumferential expansion of the cambium. In the recent growth of mature trees the yearly amount of cambial cell elongation drops as ring width decreases, but not in proportion to the decline in ring width. The cumulative elongation through lineal series of cells, per centimeter of xylem increment, increases as ring width decreases. The amount of cell elongation during the production of several narrow rings greatly exceeds that through a single wide ring having the same total width. It seems clear that the time factor is important in the elongation of cambial cells, and to some extent the interrelated frequency of anticlinal division, particularly when radial growth declines.

The Effect of Path Length and Display Size on Memory for Spatial Information

2012 ◽  
Vol 59 (3) ◽  
pp. 147-152 ◽  
Author(s):  
Katherine Guérard ◽  
Sébastien Tremblay
Keyword(s):  
Path Length ◽  
Potential Role ◽  
Spatial Information ◽  
Recall Performance ◽  
Minor Role ◽  
Length Effect ◽  
Serial Memory ◽  
Fixed Reference ◽  
A Minor

In serial memory for spatial information, some studies showed that recall performance suffers when the distance between successive locations increases relatively to the size of the display in which they are presented (the path length effect; e.g., Parmentier et al., 2005) but not when distance is increased by enlarging the size of the display (e.g., Smyth & Scholey, 1994). In the present study, we examined the effect of varying the absolute and relative distance between to-be-remembered items on memory for spatial information. We manipulated path length using small (15″) and large (64″) screens within the same design. In two experiments, we showed that distance was disruptive mainly when it is varied relatively to a fixed reference frame, though increasing the size of the display also had a small deleterious effect on recall. The insertion of a retention interval did not influence these effects, suggesting that rehearsal plays a minor role in mediating the effects of distance on serial spatial memory. We discuss the potential role of perceptual organization in light of the pattern of results.

Use of Different Tissue Thromboplastins in the Control of Anticoagulant-Therapy

1958 ◽  
Vol 02 (05/06) ◽  
pp. 462-480 ◽  
Author(s):  
Marc Verstraete ◽  
Patricia A. Clark ◽  
Irving S. Wright
Keyword(s):  
Prothrombin Time ◽  
Anticoagulant Therapy ◽  
Factor Vii ◽  
Rabbit Brain ◽  
Minor Role ◽  
Rabbit Lung ◽  
Coagulation Mechanism ◽  
Time Test ◽  
The One ◽  
A Minor

SummaryAn analysis of the results of prothrombin time tests with different types of thromboplastins sheds some light on the problem why the administration of coumarin is difficult to standardize in different centers. Our present ideas on the subject, based on experimental data may be summarized as follows.Several factors of the clotting mechanism are influenced by coumarin derivatives. The action of some of these factors is by-passed in the 1-stage prothrombin time test. The decrease of the prothrombin and factor VII levels may be evaluated in the 1-stage prothrombin time determination (Quick-test). The prolongation of the prothrombin times are, however, predominantly due to the decrease of factor VII activity, the prothrombin content remaining around 50 per cent of normal during an adequate anticoagulant therapy. It is unlikely that this degree of depression of prothrombin is of major significance in interfering with the coagulation mechanism in the protection against thromboembolism. It may, however, play a minor role, which has yet to be evaluated quantitatively. An exact evaluation of factor VII is, therefore, important for the guidance of anticoagulant therapy and the method of choice is the one which is most sensitive to changes in factor VII concentration. The 1-stage prothrombin time test with a rabbit lung thromboplastin seems the most suitable method because rabbit brain preparations exhibit a factor VII-like activity that is not present in rabbit lung preparations.

Produktivkraft als Versprechen

2016 ◽  
Vol 46 (185) ◽  
pp. 621-638 ◽  
Author(s):  
Christian Siefkes
Keyword(s):  
Private Consumption ◽  
Minor Role ◽  
Progressive Reduction ◽  
Internal Forces ◽  
A Minor

The ‘Fragment on Machines’ from Marx’s Grundrisse is often cited as an argument that the internal forces of capitalism will lead to its doom. But the argument that the progressive reduction of labor must doom capitalism lacks a proper foundation, as a comparison with the ‘Schemes of Reproduction’ given in Capital II shows. The latter, however, aren’t fully convincing either. In reality, more depends on the private consumption of capitalists than either model recognizes. Ultimately, most can be made of the ‘Fragment on Machines’ by reading it not as an exposure of capitalism’s internal contractions, but as a discussion of a possible communist future where labor (or work) will play but a minor role.

Effects of Myo-inositol Alone and in Combination with Seleno-Lmethionine on Cadmium-Induced Testicular Damage in Mice

2019 ◽  
Vol 12 (4) ◽  
pp. 311-323 ◽  
Author(s):  
Salvatore Benvenga ◽  
Antonio Micali ◽  
Giovanni Pallio ◽  
Roberto Vita ◽  
Consuelo Malta ◽  
...  
Keyword(s):  
Structural Changes ◽  
Natural Antioxidants ◽  
Minor Role ◽  
Positive Role ◽  
Testosterone Levels ◽  
Tnf Α ◽  
Testicular Lesions ◽  
A Minor ◽  
Immunohistochemical Analyses

Background: Cadmium (Cd) impairs gametogenesis and damages the blood-testis barrier. Objective: As the primary mechanism of Cd-induced damage is oxidative stress, the effects of two natural antioxidants, myo-inositol (MI) and seleno-L-methionine (Se), were evaluated in mice testes. Methods: Eighty-four male C57 BL/6J mice were divided into twelve groups: 0.9% NaCl (vehicle; 1 ml/kg/day i.p.); Se (0.2 mg/kg/day per os); Se (0.4 mg/kg/day per os); MI (360 mg/kg/day per os); MI plus Se (0.2 mg/kg/day); MI plus Se (0.4 mg/kg/day); CdCl2 (2 mg/kg/day i.p.) plus vehicle; CdCl2 plus MI; CdCl2 plus Se (0.2 mg/kg/day); CdCl2 plus Se (0.4 mg/kg/day); CdCl2 plus MI plus Se (0.2 mg/kg/day); and CdCl2 plus MI plus Se (0.4 mg/kg/day). After 14 days, testes were processed for biochemical, structural and immunohistochemical analyses. Results: CdCl2 increased iNOS and TNF-α expression and Malondialdehyde (MDA) levels, lowered glutathione (GSH) and testosterone, induced testicular lesions, and almost eliminated claudin-11 immunoreactivity. Se administration at 0.2 or 0.4 mg/kg significantly reduced iNOS and TNF-α expression, maintained GSH, MDA and testosterone levels, structural changes and low claudin-11 immunoreactivity. MI alone or associated with Se at 0.2 or 0.4 mg/kg significantly reduced iNOS and TNF-α expression and MDA levels, increased GSH and testosterone levels, ameliorated structural organization and increased claudin-11 patches number. Conclusion: We demonstrated a protective effect of MI, a minor role of Se and an evident positive role of the association between MI and Se on Cd-induced damages of the testis. MI alone or associated with Se might protect testes in subjects exposed to toxicants, at least to those with behavior similar to Cd.

Extraction of strontium and barium salts by the nitrobenzene solution of dicarbolide in the presence of glymes

1985 ◽  
Vol 50 (3) ◽  
pp. 581-599 ◽  
Author(s):  
Petr Vaňura ◽  
Emanuel Makrlík
Keyword(s):  
Stability Constants ◽  
Organic Phase ◽  
Equilibrium Constants ◽  
Minor Role ◽  
Nitrobenzene Solution ◽  
Ligand Structure ◽  
Stability Constants Of Complexes ◽  
Separation Factors ◽  
The Stability ◽  
A Minor

Extraction of microamounts of Sr2+ and Ba2+ (henceforth M2+) from the aqueous solutions of perchloric acid (0.0125-1.02 mol/l) by means of the nitrobenzene solutions of dicarbolide (0.004-0.05 mol/l of H+{Co(C2B9H11)2}-) was studied in the presence of monoglyme (only Ba2+), diglyme, triglyme, and tetraglyme (CH3O-(CH2-CH2O)nCH3, where n = 1, 2, 3, 4). The distribution of glyme betweeen the aqueous and organic phases, the extraction of the protonized glyme molecule HL+ together with the extraction of M2+ ion and of the glyme complex with the M2+ ion, i.e., ML2+ (where L is the molecule of glyme), were found to be the dominating reactions in the systems under study. In the systems with tri- and tetraglymes the extraction of H+ and M2+ ions solvated with two glyme molecules, i.e., the formation of HL2+ and ML22+ species, can probably play a minor role. The values of the respective equilibrium constants, of the stability constants of complexes formed in the organic phase, and the theoretical separation factors αBa/Sr were determined. The effect of the ligand structure on the values of extraction and stability constants in the organic phase is discussed.

scholarly journals The preendosomal compartment comprises distinct coated and noncoated endocytic vesicle populations.

1991 ◽  
Vol 113 (4) ◽  
pp. 731-741 ◽  
Author(s):  
S H Hansen ◽  
K Sandvig ◽  
B van Deurs
Keyword(s):  
Cell Surface ◽  
Coated Vesicles ◽  
Minor Role ◽  
Specific Marker ◽  
Con A ◽  
Early Endosomes ◽  
Gold Conjugate ◽  
Entire Cell ◽  
A Minor ◽  
Endocytic Vesicles

The transfer of molecules from the cell surface to the early endosomes is mediated by preendosomal vesicles. These vesicles, which have pinched off completely from the plasma membrane but not yet fused with endosomes, form the earliest compartment along the endocytic route. Using a new assay to distinguish between free and cell surface connected vesicle profiles, we have characterized the preedosomal compartment ultrastructurally. Our basic experimental setup was labeling of the entire cell surface at 4 degrees C with Con A-gold, warming of the cells to 37 degrees C to allow endocytosis, followed by replacing incubation medium with fixative, all within either 30 or 60 s. Then the fixed cells were incubated with anti-Con A-HRP to distinguish truly free (gold labeled) endocytic vesicles from surface-connected structures. Finally, analysis of thin (20-30 nm) serial sections and quantification of vesicle diameters were carried out. Based on this approach it is shown that the preendosomal compartment comprises both clathrin-coated and non-coated endocytic vesicles with approximately the same frequency but with distinct diameter distributions, the average noncoated vesicle being smaller (95 nm) than the average coated one (110 nm). In parallel experiments, using an anti-transferrin receptor gold-conjugate as a specific marker for clathrin-dependent endocytosis it is also shown that uncoating of coated vesicles plays only a minor role for the total frequency of noncoated vesicles. Furthermore, after perturbation of clathrin-dependent endocytosis by potassium depletion where uptake of transferrin is blocked, noncoated endocytic vesicles with Con A-gold, but not coated vesicles, exist already after 30 and 60 s. Finally, it is shown that the existence of small, free vesicles in the short-time experiments cannot be ascribed to recycling from the early endosomes.

scholarly journals Sun Protection and Sunburn in Children Aged 1–10 Years in Germany: Prevalence and Determinants

Children ◽  
2021 ◽  
Vol 8 (8) ◽  
pp. 668
Author(s):  
Tatiana Görig ◽  
Corinna Södel ◽  
Annette B. Pfahlberg ◽  
Olaf Gefeller ◽  
Eckhard W. Breitbart ◽  
...  
Keyword(s):  
Role Models ◽  
Skin Color ◽  
Role Model ◽  
Sun Protection ◽  
Minor Role ◽  
Positive Role ◽  
Protection Measures ◽  
Telephone Interviews ◽  
The Past ◽  
A Minor

Seeking shade, the use of textile sun protection and sunscreen, and protecting one’s eyes by wearing sunglasses are recommended sun protection measures in children. We aimed to quantify the use of these measures as well as the prevalence of sunburn in children aged 1 to 10 years in Germany and to identify their determinants. Data collected via telephone interviews in a nationwide sample of 554 parents or caregivers in family were analyzed. Use of sunscreen was the most common measure applied (77.8%), while sunglasses were least frequently used (12.5%). The prevalence of sunburn during the past year was 21.8%, and it was positively associated with children’s age. The use of sun protection measures was significantly associated with the age and skin color of the child, while characteristics and tanning behaviors of the caregivers only played a minor role. The use of sun protection measures was higher when caregivers perceived themselves as a role model (Odds Ratio (OR) = 4.33, p < 0.001). Our nationwide data show that there remains a need for the improved use of sun protection measures, especially in children aged 7 to 10 years. In educational material, parents should be encouraged to become positive role models for their children regarding sun protection.

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