scholarly journals 156 Effects of the Inductive Period, Shoot Density, and Leaf Removal on the Flowering of Heliconia rostrata Ruiz & Pavon

HortScience ◽  
2000 ◽  
Vol 35 (3) ◽  
pp. 416E-417
Author(s):  
Norberto Maciel ◽  
Richard A. Criley

Heliconia rostrata is a herbaceous-musoid sympodial rhizomatous plant that grows as clump. After three leaves are produced, each shoot of the clump may bear an inflorescence if it is induced by short days (SD). However, the relationship between shoot density and flowering has not been quantified. To evaluate the effects of the inductive period, number of shoots, and leaf removal on flowering, rhizomes were planted in 120 pots (8 L). One-third of the pots were planted with two rhizomes, while the remainder was planted with one. One-half of the pots with one rhizome were allowed to develop all their shoots for three generations, while in the remaining pots only one shoot per generation was allowed to grow. In addition, one-half of the plants in all the treatments were subjected to selective leaf removal. The plants were grown under long days (LD) >13 h in a glasshouse until four leaves were produced. Inductive SD was supplied to all the plants from 5:00 pm to 8:00 am. After 8 weeks of SD, one-half of the plants were given LD, while the other half continued under SD (conSD) until flowering. The highest percentage of flowering shoots (39% to 35%) was observed in plants under conSD; plants under SD-LD were 10% to 9%. The second generation of shoots showed the highest flowering (74% conSD and 21% SD-LD), followed by the first (62% conSD and 18% SD-LD), and third (31% conSD and 0% SD-LD) generations. Non-flowering shoots of the first generation were aborted or dead. Shoots of the third were still vegetative, since they had few leaves to be induced. Fewer flowers occurred in clumps allowed to develop all their shoots. Intact plants from rhizomes with one shoot per generation flowered more than the partially defoliated ones under conSD.

1951 ◽  
Vol 42 (1) ◽  
pp. 185-194
Author(s):  
J. R. Busvine ◽  
N. F. Wilson

An experiment on a semi-practical scale was made to determine the effectiveness of DDT treatment to a new house, in quelling an infestation of bed-bugs introduced with untreated furniture. Two small huts were constructed, one being finally treated with DDT, the other acting as a control. Rabbits introduced nightly represented the hosts and infested rabbit-hutches the furniture.Forty adult bugs were introduced on the infested hutches in each hut. In the untreated chamber, the bug population soared up to over 400 in six months. In the treated hut the population remained at 10 to 20 up to the end of the experiment (28 weeks) ; these bugs remained in the untreated hutch. Translating these results to practical conditions, it appears that a bug colony might persist in an untreated bed in a room sprayed with DDT. However, the wandering bugs would be destroyed which would severely check population growth and prevent a heavy and widespread infestation.Observations in the untreated hut indicated the decline of the first generation adults, the rise and decline of the second generation and emergence of the third.A few preliminary tests with marked bugs proved that these insects do not usually return to the same site after going to the host to take a meal.


1979 ◽  
Vol 57 (3) ◽  
pp. 627-639 ◽  
Author(s):  
C. Back ◽  
P. P. Harper

A study of the distribution and the emergence of blackflies in 33 stations in streams at the Saint Hippolyte Biology Station gives the following dynamic picture: (1) The main emergence starts in May with the appearance of the univoltine species that have grown through the winter, followed by the first generation of spring-growing or summer-growing polyvoltine species. The predominance of the eurytopic univoltine species, mainly Prosimulium fuscum and Cnephia mutata, explains the presence of blackflies in nearly all the stations. (2) In July the second generation of the polyvoltine species appears, Simulium decorum, S. vittatum, S. aureum, S. verecundum, S. croxtoni, and S. vernum; these species lend to be more stenotopic, which restricts emergence mainly to stations near lake outlets; the other stations harbour only small populations of S. tuberosum. (3) The same distribution is evident in late August and early September when the third generation of the polyvoltine species matures, particularly S. tuberosum, S. aureum, and S. verecundum. A wet and cool summer tends to favour the development of large populations of blackflies.


Author(s):  
Daniel Martin Feige

Der Beitrag widmet sich der Frage historischer Folgeverhältnisse in der Kunst. Gegenüber dem Gedanken, dass es ein ursprüngliches Werk in der Reihe von Werken gibt, das späteren Werken seinen Sinn gibt, schlägt der Text vor, das Verhältnis umgekehrt zu denken: Im Lichte späterer Werke wird der Sinn früherer Werke neu ausgehandelt. Dazu geht der Text in drei Schritten vor. Im ersten Teil formuliert er unter der Überschrift ›Form‹ in kritischer Abgrenzung zu Danto und Eco mit Adorno den Gedanken, dass Kunstwerke eigensinnig konstituierte Gegenstände sind. Die im Gedanken der Neuverhandlung früherer Werke im Lichte späterer Werke vorausgesetzte Unbestimmtheit des Sinns von Kunstwerken wird im zweiten Teil unter dem Schlagwort ›Zeitlichkeit‹ anhand des Paradigmas der Improvisation erörtert. Der dritte und letzte Teil wendet diese improvisatorische Logik unter dem Label ›Neuaushandlung‹ dann dezidiert auf das Verhältnis von Vorbild und Nachbild an. The article proposes a new understanding of historical succession in the realm of art. In contrast to the idea that there is an original work in the series of works that gives meaning to the works that come later, the text proposes to think it exactly the other way round: in the light of later works, the meanings of earlier works are renegotiated. The text proceeds in three steps to develop this idea. Under the heading ›Form‹ it develops in the first part a critical reading of Danto’s and Eco’s notion of the constitution of the artworks and argues with Adorno that each powerful work develops its own language. In the second part, the vagueness of the meaning of works of art presupposed in the idea of renegotiating earlier works in the light of later works is discussed under the term ›Temporality‹ in terms of the logic of improvisation. The third and final part uses this improvisational logic under the label ›Renegotiation‹ to understand the relationship between model and afterimage in the realm of art.


1965 ◽  
Vol 97 (12) ◽  
pp. 1303-1318 ◽  
Author(s):  
H. J. Herbert

AbstractIn Nova Scotia one leaf cluster with an adjoining 1 inch of twig taken from the inside of each of 10 apple trees replicated four times is an adequate sample unit to measure the density of the brown mite.The brown mite has one generation with a partial second in some orchards and one with a partial second and partial third in others. The first generation adults in the bivoltine and trivoltine populations lay summer eggs on the leaves and twigs, and diapause eggs on tin twigs. The second generation adults in the bivoltine populations lay only diapause eggs; in the trivoltine populations they lay both summer and diapause eggs. The adults of the third generation lay only diapause eggs.The brown mite is found on both the leaves and woody parts of the tree. In orchards with bivoltine populations the proportion of mites on leaves reached a peak of 80% by mid-July, but thereafter gradually decreased to 10% by the end of August. However, in orchards with trivoltine populations the proportion of mites on leaves reached a peak of 80 to 90% by mid-July, remained constant until mid-August, and thereafter decreased to approximately 40% by the end of August.The number of diapause eggs laid by adults of each generation in both the bivoltine and trivoltine populations varies widely. The eggs are deposited on the trunk as well as on the branches, with the heaviest deposition in the central area of the tree. The diapause eggs laid by adults of the first generation are the last to hatch and those laid by the third generation are the first to hatch the following spring.The factors responsible for the differences in the number of generations and in the number of diapause eggs laid are unknown.


Author(s):  
Robert Jackson ◽  
Georg Sørensen

This chapter examines three important debates in International Political Economy (IPE). The first debate concerns power and the relationship between politics and economics, and more specifically whether politics is in charge of economics or whether it is the other way around. The second debate deals with development and underdevelopment in developing countries. The third debate is about the nature and extent of economic globalization, and currently takes places in a context of increasing inequality between and inside countries. This debate is also informed by the serious financial crisis of 2008 and has raised questions regarding the viability of the current model of capitalism in the United States and Western Europe.


2020 ◽  
Vol 24 (4) ◽  
pp. 861-880 ◽  
Author(s):  
Ksenia Gnevsheva

Aims and Objectives/Purpose/Research Questions: The paper aimed to investigate style-shifting in the use of ethnolectal features in first- and second- generation bilingual migrants. Design/Methodology/Approach: Three groups of speakers (first- and second-generation Russian–English bilinguals as well as monolingual Anglo Australians) were audio-recorded in three different styles (conversation, interview, and reading). Data and Analysis: Their production of the goose and trap vowels across the styles was analyzed quantitatively. Findings/Conclusions: Overall differences were found between the groups such that first- and second-generation speakers produced more Russian-like vowels compared to the monolinguals; with the biggest differences between the first-generation speakers and the other two groups. In terms of style-shifting, no significant differences were found in the monolingual speakers, and both first- and second-generation speakers were found to produce most Australian English-like vowels in the conversation style. At the same time, certain differences between the two bilingual groups surfaced, such as no significant differences in the first-generation speakers’ production of the goose vowel and in the vowels’ linguistic conditioning. Originality: Previous studies have compared ethnolects in the first- and second-generations of migrants and mainstream varieties in order to theorize ethnolect formation. Several studies have also investigated intraspeaker style-shifting between more ‘mainstream’ and more ‘ethnic’ in ethnolect speakers, but such style-shifting is rarely compared across generations. Significance/Implications: The similarities and differences between the two bilingual groups suggest that ethnolectal features may be originally derived from the community language but may be reallocated to other sociolinguistic meanings in the second generation.


2009 ◽  
Vol 46 (2) ◽  
pp. 273-330 ◽  
Author(s):  
MARKUS BADER ◽  
JANA HÄUSSLER

This paper presents three experiments that investigate the relationship between gradient and binary judgments of grammaticality. In the first two experiments, two different groups of participants judged sentences by the method of magnitude estimation and by the method of speeded grammaticality judgments in a single session. The two experiments involved identical sentence materials but they differed in the order in which the two procedures were applied. The results show a high correlation between the magnitude estimation data and the speeded grammaticality judgments data, both within a session and across the two sessions. The third experiment was a questionnaire study in which participants judged the same sentences as either grammatical or ungrammatical without time pressure. This experiment yielded results quite similar to those of the other two experiments. Thus gradient and binary judgments both provide valuable and reliable sources for linguistic theory when assessed in an experimentally controlled way. We present a model based on Signal Detection Theory which specifies how gradient grammaticality scores are mapped to binary grammaticality judgments. Finally, we compare our experimental results to existing corpus data in order to inquire into the relationship between grammaticality and frequency of usage.


1979 ◽  
Vol 41 (2) ◽  
pp. 256-272
Author(s):  
Kenneth W. Thompson

I propose to examine the relationship of American democracy to the Third World along two planes of reality, one briefly sketched in outline and miniature, the other drawn with greater elaboration and substance. The brief sketch sums up all that follows; it draws on America's great leader, Abraham Lincoln, who prophetically defined the issues that faced both the young American republic and today's fledgling nations by asking the question:Must a government of necessity be too strong for the liberties of its people, or too weak to maintain its own existence?


2021 ◽  
Author(s):  
◽  
Rebecca Bloore

<p><b>The ways in which people regulate their emotions is central to achieving wellbeing in our everyday lives. Typically it is assumed that everyone tries to experience the positive and avoid the negative, however research conducted over the last decade has demonstrated that not everyone is motivated to experience valenced emotions in this normative ‘hedonic’ fashion all of the time. Sometimes people hold and seek to satisfy ‘contra-hedonic’ motives, i.e., trying to experience negative emotions. To investigate the implications of holding one or the other type of motive, this thesis is composed of three studies that investigate the implications of holding these types of motives for emotions: 1) the first paper determined whether the motive to avoid happiness predicts depressive symptoms through the mechanism of lessened hope, 2) the second paper featured the development of a new measure designed to assess a broad range of motives for emotions, and 3) the third paper described the associations between this new measure with a commonly used emotion regulation measure.</b></p> <p>The first research paper addresses the phenomenon that some individuals do not approach and seek to experience happiness in a normative fashion. Research on this so-called ‘fear of happiness’ or ‘happiness aversion’ tendency has identified about 10-15% of community samples as composed of individuals who report not wanting to experience happy mood states. Importantly these individuals repeatedly also report elevated levels of depressive symptoms. In this study, I sought to investigate the associations among happiness aversion, hope (a protective factor against negative mood states), and depressive symptoms. Evidence was found that hope functioned both as a mediator as well as a buffer between happiness aversion and resultant depressive symptoms in a concurrent sample of 588 undergraduate psychology students. Follow-up exploratory analysis with a small longitudinal sample suggested that the concurrent findings were replicated across time. Overall findings within Study 1 suggested that interventions which promote hope can be effective in disrupting the relationship between happiness aversion and depressive symptoms.</p> <p>Happiness aversion research, similar to Study 1 described above, has documented that some individuals are motivated to avoid experiencing happiness (this non-conventional approach is termed ‘contra-hedonic’). I then asked: what about other emotions? Would it be feasible and interesting to assess how individuals try to experience and try to avoid experiencing a range of positive AND negative emotions? The second paper of this thesis describes the development of a new self-report measure, termed the General Emotion Regulation Measure (GERM), that assesses how people are motivated to experience or avoid experiencing clusters of positive and negative emotions in their everyday lives. This paper describes the literature concerning positive and negative emotion regulation motivations (both hedonic and contra-hedonic types) and shows how the new measure provides new information about people’s emotion motives. Latent profile analysis (LPA) was implemented to explore individual differences in general emotion motives, and three different profiles of individuals were identified. In a sample of 833 undergraduate students, a LPA identified these distinct profiles: 1) a normative group in which people tried to experience positive emotions and tried to avoid experiencing negative emotions; 2) a non-normative group which exhibited an aversion to positive emotions and an attraction to negative emotions; and 3) another non-normative group which displayed an unwillingness or inability to regulate either positive or negative emotions. Comparisons of psychological wellbeing were computed among the three profiles using a MANOVA: it identified that the normative group reported higher levels of wellbeing (e.g., optimism) and lower levels of illbeing (e.g., depressive symptoms) compared to the other two groups. The new GERM measure highlights the general utility of these general emotion regulation motives, which, arguably, can be used to inform research on wellbeing across a wide range of psychological fields.</p> <p>The final and concluding paper within this thesis examined whether the GERM is effective in predicting facets of the commonly used emotion dysregulation scale, the Difficulties in Emotion Regulation Scale (DERS). Further, emotion dysregulation was predicted to mediate the relationship between emotion motives identified by the GERM measure and depressive symptoms. Based on previous research, it was expected that the two contra-hedonic motives’ relationships (trying to experience negative emotions and trying to avoid experiencing positive emotions) with depressive symptoms would be mediated by facets of emotion dysregulation. Findings demonstrated that two facets of emotion dysregulation, namely, lack of impulse control and lack of access to strategies, fully mediated the relationship between both contra-hedonic ER motives and depressive symptoms. The third paper demonstrated that contra-hedonic motives predict depressive outcomes through the use and instantiation of several different facets of emotion regulation difficulties. These results show that emotion motives are important in regards to setting the stage for maladaptive emotion regulation strategies and depressive symptoms.</p> <p>The three studies’ findings show that the ways in which we manage our emotions in our daily lives are guided and constrained by how individuals are motivated to experience positive and negative emotions. These studies highlight the importance that motivation has in directing individuals to choose particular ways to regulate their emotions, and these, in turn, have important effects for emotional wellbeing.</p>


Author(s):  
Arkebe Oqubay

Contemporary industrial hubs evolved in East Asia after the 1950s and have been associated with the industrial catch-up of the East Asian economies and their industrial policies. This chapter has three main objectives: to depict the path of hubs development in these pioneering economies and provide a synthesis of the East Asian experience; to extract relevant lessons for policymakers and practitioners; and to provide a perspective on how industrial hubs can synergize industrialization and technological catch-up. Although there are commonalities, experiences have been uneven across these economies with different stages of development. The experiences of the first-generation industrial hubs, namely, Taiwan (China), South Korea, and Singapore are reviewed, followed by China as the second generation. A synthesis, key observations, and conclusions are reviewed. The chapter will complement the other chapters under Part IV through synthesis and lessons, while it complements the analytical perspectives under Parts I and II of the Handbook, by building on arguments and conceptual perspectives.


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