A field study of competition and interaction between Lemna minor and Lemna trisulca

1989 ◽  
Vol 67 (10) ◽  
pp. 2904-2911 ◽  
Author(s):  
Alexander L. McIlraith ◽  
Gordon G. C. Robinson ◽  
Jennifer M. Shay
Keyword(s):  
Life History ◽  
Field Study ◽  
Key Words ◽  
Field Experiments ◽  
Lemna Minor ◽  
Survey Methods ◽  
The Other ◽  
Transplant Experiment ◽  
Replacement Series ◽  
Vegetative Biomass

Field experiments and survey methods were used to assess competition and interaction between Lemna minor L. and Lemna trisulca L. at Delta Marsh, Manitoba. Sites were dominated by one or the other species or codominated by both. Replacement series experiments predicted codominance of L. minor and L. trisulca in an unshaded eutrophic site but predicted L. minor dominance when run for a longer time. Similar experiments conducted in a shaded eutrophic site predicted L. minor dominance. Addition series experiments showed that intraspecific and interspecific competition occurred in the unshaded site. In a eutrophic unshaded ditch, high densities of L. minor suppressed L. trisulca. In a eutrophic shaded site, high densities of L. minor and green algae inhibited L. trisulca, and in a sunny, less eutrophic site high density of each species inhibited the other. In a transplant experiment, L. minor biomass in shaded enclosures approached that found naturally in two shaded sites. Lemna trisulca persisted when shaded. Vegetative biomass trends in an unshaded eutrophic marsh ditch indicated spring and fall L. trisulca dominance and summer L. minor dominance. Shaded eutrophic sites were dominated by L. minor, whereas a less eutrophic site was dominated by L. trisulca. A model is developed to explain dominance patterns, and seasonal life-history responses are considered. Key words: Lemna, duckweed, competition, interaction, resources, light, nutrients.

A field study of rugose leaf curl virus infection in stoloniferous Trifolium species

1972 ◽  
Vol 12 (56) ◽  
pp. 293 ◽  
Author(s):  
NE Grylls ◽  
JC Galletly ◽  
RC Campbell
Keyword(s):  
Field Study ◽  
Field Experiments ◽  
The Other ◽  
Symptom Expression ◽  
Disease Symptoms ◽  
Disease Vector ◽  
Agricultural College ◽  
Low Incidence ◽  
Leaf Curl Virus ◽  
Leaf Curl

A field study was made of rugose leaf curl virus (RLCV) infection in four stoloniferous clovers ; New Zealand White and Irrigation White, cultivars of Trifolium repens, and two species from Africa, T. semipilosum and T. burchellianum. Half of the plants used were inoculated in the greenhouse, and, of these, 20 per cent showed symptoms of RLCV when they were planted in the field. The plants were grown in two field experiments on different sites at the Queensland Agricultural College, Lawes. The disease vector Austroagallia torrida was generally present over site 1 in larger numbers than over site 2. Pre-inoculated plants maintained a higher level of infection throughout the experiment. Over 40 per cent of plants not pre-inoculated developed the disease symptoms in the field, but the level of infection was consistently higher at site 1. T. semipilosum showed higher rates of infection than other species, but this species has greater drought resistance, and drought stress tended to mask symptom expression in the other species. Of 733 plants that showed infection during the experiment, 530 wholly or partially recovered from the disease, and, of these, only 38 became re-infected later in the experiment. The high percentage of recovery of infected plants, and the low percentage of re-infection of these recovered plants in the field supports earlier greenhouse studies, and suggests a possible reason for the low incidence of RLCV in old established stoloniferous clover pastures in southern Queensland.

PELAKSANAAN HUKUM KEWARISAN ISLAM DI PENGADILAN AGAMA BANTEN

ALQALAM ◽  
2013 ◽  
Vol 30 (1) ◽  
pp. 158
Author(s):  
Yusuf Somawinata
Keyword(s):  
Key Words ◽  
Islamic Law ◽  
Survey Methods ◽  
Adopted Children ◽  
Inheritance Law ◽  
Library Research ◽  
The Ideal

This article aims at describing the obseroance of wasiat wajibah (compulsory bequeathment) in the Islamic court of Banten, analyzing the provision of the substitute heir and adopted children in the Compilation of  Islamic Law (KHI). In addition, the ideal laws to manage the innheritance rules in Indonesia. This article is library research by using doctrinal approach and using case study and survey methods. The data was, then, analyzed by using analytical descriptive and analytical correlative methods. The result showed that the observance of wasiat wajibah in the Islamic court of  Banten employed by judges is by using the Mawali Hazairin’s Doctrine. The criteria of the adoption of substitute heir and adopted children in the KHI is the attempts of Ulama and many judgees junst in giving legal justice and certainty to the society.   Key Words: Islamic Inheritance Law, Compilation of Islamic Law, Islamic court of  Banten

Ritualinis mandagumas (ta’ârof) šiuolaikinio Irano visuomenėje ir tarpkultūrinėje komunikacijoje: Teherano šiaurinės dalies atvejis

2019 ◽  
Vol 19 (28) 2019 ◽  
pp. 169-190
Author(s):  
Dalia Sabaliauskienė
Keyword(s):  
Field Study ◽  
Key Words ◽  
Intercultural Communication ◽  
Capital City ◽  
Cultural Environment ◽  
City Culture ◽  
Face Maintenance

This paper examines the concept and practices of the Iranian ritual courtesy ta’ârof in northern Tehran, based on field-study findings, and analyses its expression in intercultural communication. It examines how contemporary Iranians perceive ta’ârof, what practices of ritual courtesy are commonly found, and whether configurations of the Iranian code of courtesy remain stable in the changing cultural environment. The study employs the theory of face maintenance and data from Iranian face and diaspora research. It shows emic perceptions of ta’ârof, and reveals its practices in Tehran, alongside tendencies of expression among Iranians living in Lithuania. Key words: ta’ârof, ritual courtesy, capital-city culture, intercultural communication, contemporary Iran.

HISTOPATHOLOGY OF THE PIGMENTED TUMORAL-LIKE LESIONS OF THE SKIN AT HUE HOSPITAL OF MEDICINE AND PHARMACY UNIVERSITY

2018 ◽  
Vol 8 (4) ◽  
pp. 65-69
Author(s):  
Mao Nguyen Van ◽  
Dong Tran Nam
Keyword(s):  
Key Words ◽  
Definitive Diagnosis ◽  
The Other ◽  
Cell Tumour ◽  
Cross Sectional ◽  
Skin Tumour ◽  
Clinical Appearance ◽  
The Face ◽  
The Common ◽  
Difficult Cases

Background: Pigmented tumour of the skin is one of the common tumour in human including the benign pigmented tumours (more common) called Nevi tumours and the malignant one called melanoma which was less frequent but the most poor in prognosis. In addition, the others not belonging to these group had the same clinical appearance, so the application of histopathology and immunohistochemistry for the definitive diagnosis was indespensible. Objectives: 1. To describe the macroscopic features of the pigmented tumoral-like lesions; 2. To classify the histopathologic types of the pigmented cell tumours and the other pigmented tumours of the skin. Materials and Method: Cross-sectional research on 55 patients diagnosed as pigmented tumoral lesions by clinician, then all definitively diagnosed by histopathology combining the immunohistochemistry in difficult cases. Results: There was no difference in gender, the disease was discovered most common in adult, especially with the age over 51 years old (58.1%). the most region located was in the face accounting for 60%, following the trunk and limbs (14.6%, 12.8% respectively). All 3 malignant melanomas happened in foot. The most common color of the lesions was black (65.4%), the other ones were rose, grey and blue. Histopathology and immunohisthochemistry showed that the true pigmented cell tumours were 52.6% encompassing benign ones (Nevi tumour) (41.8%), melanoma (5.4%) and lentigo (5.4%). 47.4% was not the true pigmented cell tumour including pigmented basocellular carcinoma (36.4%) and the others less common as histiofibromas, acanthoma and papilloma. Conclusion: the pigmented tumoral-like lesions of the skin could be the true pigmented cell tumours and the others, so the application of the histopathology and the immunohistochemistry after the clinical discovery helps to determine and classify the disease definitely and for the best orientation of treatment as well. Key words: skin tumour, benign pigmented tumour (Nevi), malignant pigmented tumour (melanoma), pigmented basocellular carcinoma

scholarly journals Testing the Effect of Hedge Height on Perceived Safety—A Landscape Design Intervention

2021 ◽  
Vol 13 (9) ◽  
pp. 5063
Author(s):  
Katinka H. Evensen ◽  
Helena Nordh ◽  
Ramzi Hassan ◽  
Aslak Fyhri
Keyword(s):  
Field Study ◽  
Field Experiments ◽  
Landscape Design ◽  
Urban Environments ◽  
Space Management ◽  
Perceived Safety ◽  
Urban Green Spaces ◽  
Outdoor Spaces ◽  
Surrounding Areas ◽  
The Impact

Access to safe, green urban environments is important for quality of life in cities. The objective of this study is to explore the impact of a safety-enhancing landscape design measure on visitors’ experiences in an urban park. Additionally, this paper combines the use of field and virtual reality (VR) experiments, contributing methodological insights into how to evaluate safety measures in green space management and research on perceived safety. In a field experiment (n = 266), we explored whether the height of a hedge along a pathway influenced perceived safety among users. The field study showed that cutting down the hedge improved the perceived prospect of the immediate surrounding areas for female users, which again made them feel safer in the park. We developed a VR experiment for an evening scenario in the same environment (n = 19) to supplement the field study and test the effect of the intervention further. The VR experiment also found a gender effect on perceived safety, with females reporting lower perceived safety, but no effect was shown for the height of the hedge. The results in this study show that environmental attributes such as perceived prospect and concealment should be considered in the design and management of urban green spaces. Additionally, this research demonstrates an approach to conducting field experiments to test the effects of actual design interventions and then further developing these experiments using VR technology. Further research on perceived safety in outdoor spaces is needed to make use of this combined method’s potential.

scholarly journals Effect of seed treatment and foliar spray with fungicides in controlling black point disease of wheat

1970 ◽  
Vol 34 (3) ◽  
pp. 425-434 ◽  
Author(s):  
PK Malaker ◽  
IH Mian
Keyword(s):  
Economic Analysis ◽  
Grain Yield ◽  
Key Words ◽  
Seed Weight ◽  
Seed Treatment ◽  
Foliar Spray ◽  
The Other ◽  
Gross Margin ◽  
Black Point ◽  
Wheat Seeds

The efficacy of seed treatment and foliar spray with fungicides in controlling black point incidence of wheat seeds was evaluated in the field. Two seed treating fungicides, namely Vitavax-200 and Homai-80WP were used @ 0.25% of dry seed weight and foliar spray with Tilt-250EC (0.05%) was applied in six different schedules. Untreated and unsprayed controls were also maintained. Seed treatment with either Vitavax-200 or Homai-80WP significantly increased plant population and grain yield, but none of them was found effective in reducing black point incidence. On the other hand, foliar sprays with Tilt-250EC under all the spray schedules except spraying at 70 and 90 DAS significantly minimized the disease severity over unsprayed control. Among the different spray schedules, spraying at 30, 40, 50, 60, 70, 80, and 90 DAS appeared to be most effective, which was similar to spraying at 30, 45, 60, 75, and 90 DAS in reducing black point incidence and increasing grain yield. Economic analysis on yield advantage showed that the highest additional gross margin of Tk. 6120/ha with BCR 2.57 was obtained from five sprays applied at 30, 45, 60, 75, and 90 DAS. Key Words: Seed treatment, foliar spray, black point, wheat. DOI: 10.3329/bjar.v34i3.3968 Bangladesh J. Agril. Res. 34(3) : 425-434, September 2009

Structural effects on chemo- and enantioselectivity of Candida antarctica lipase B - Resolution of β-amino esters

2002 ◽  
Vol 80 (6) ◽  
pp. 565-570 ◽  
Author(s):  
Szilvia Gedey ◽  
Arto Liljeblad ◽  
László Lázár ◽  
Ferenc Fülöp ◽  
Liisa T Kanerva
Keyword(s):  
Key Words ◽  
Candida Antarctica ◽  
Diisopropyl Ether ◽  
The Other ◽  
Candida Antarctica Lipase B ◽  
Candida Antarctica Lipase ◽  
Structural Effects ◽  
Lipase B ◽  
Amino Esters ◽  
Catalyzed Reactions

The Candida antarctica lipase B-catalyzed reactions of five β-amino esters with neat butyl butanoate and with 2,2,2-trifluoroethyl butanoate in diisopropyl ether were studied, as were the reactions of the same β-amino esters and their N-butanamides with neat butanol. The possibility for sequential resolution, where the amino and ester functions of the substrate both react with an achiral butanoate, became less likely with increasing size of the substrate from ethyl 3-aminobutanoate (1a) to pentanoate (1b) or larger. On the other hand, the alcoholyses of N-acylated β-amino esters successfully proceeded in butanol with E > 100. Gram-scale resolution of the N-butanoylated 1a was performed to demonstrate the usefulness of the method. Key words: lipase, interesterification, acylation, alcoholysis, resolution, β-amino esters.

An assessment of the factors controlling the productivity of maize in England

1951 ◽  
Vol 41 (3) ◽  
pp. 271-281 ◽  
Author(s):  
E. S. Bunting ◽  
G. E. Blackman
Keyword(s):  
Dry Matter ◽  
Field Experiments ◽  
Plant Density ◽  
Spatial Arrangement ◽  
The Other ◽  
Mass Selection ◽  
Grain Production ◽  
Forage Production ◽  
Field Scale ◽  
Other Hand

Between 1942 and 1950, some thirty field experiments have been carried out in the southern half of England to assess the potential value, either for grain or forage production, of seventeen openpollinated flint or dent maizes together with twentynine single or double hybrids of American or Canadian origin.Early-maturing flint varieties will consistently ripen grain, but before mechanical threshing or storage, the cobs require drying. Sibthorp, a mass selection made from an unknown German variety, is the earliest and most productive flint maize so far tested, and in the experiments has yielded as much as 39 cwt. of grain per acre with an average of 24 cwt. The earliest American hybrids, i.e. those with a U.S.A. rating of 80 days from sowing to maturity, give very high yields of grain in favourable seasons. Within the group Wisconsin 240–275, a yield level equal to or exceeding 50 cwt./acre has on occasion been recorded. On the other hand, in the most unfavourable years, such hybrids just failed to produce ripe cobs.Attempts to maintain sixty-five parent inlines of the earliest hybrids have largely failed. However, many of the parent single crosses have matured, and the production on a field scale of the double-cross seed of both Wisconsin 240 and 255 has been carried out.Spacing experiments indicate that for optimum grain production a density of 6 plants/sq.yd. is required for both flint varieties and the earliest hybrids. A spatial arrangement of individual plants is to be preferred to that of groups or hills.American hybrids, in the class of ‘90 days’ to maturity, will in all but the most unfavourable seasons reach the ‘early-dent’ stage of the grain before the incidence of autumn frosts. Yields of dry matter of plants harvested in this phase have ranged from 30 to 85 cwt. of dry matter per acre. In these trials, the plant density was standardized at 4 plants/sq.yd. and higher densities may be demanded for optimal yields.The ratio of the ‘ear’ (that is, the cob, immature grain and enclosing leaf sheaths) to the total shoot weight at harvest varies greatly with the variety or hybrid. With White Horsetooth, the usual variety grown for fodder in England, no cobs are formed before the plants are killed by frost, while with the early hybrids, the ear may be half the weight of the whole shoot.The earliest variety Sibthorp from an early May sowing takes approximately 70–80 days to reach full anthesis, while ‘80-day’ American hybrids are a week later. From sowing to full maturity the period in England is from 140 to 160 days, thus compared to conditions in Minnesota the period is nearly twice as long. Because of the much slower rate of development and because of the humidity of English autumns, it is concluded that until the date of maturity can be advanced some 14 days, grain production on a field scale is not yet feasible. On the other hand, many of the American hybrids are well fitted to the production of silage. The greatest drawback to the introduction of such hybrids is the liability of the seed and seedlings to be attacked by rooks.

A field study of reproductive interactions in Bosca's newt, Triturus boscai

1995 ◽  
Vol 16 (4) ◽  
pp. 357-374 ◽  
Author(s):  
Manuel Mouta Faria
Keyword(s):  
Field Study ◽  
Natural Population ◽  
Wild Population ◽  
Short Circuit ◽  
The Other ◽  
Courtship Behaviour ◽  
Laboratory Studies ◽  
Free Living ◽  
Spermatophore Transfer ◽  
Sexual Interference

AbstractObservations of a free-living population of Bosca's newt, Triturus boscai, show that courtship behaviour in nature is similar to the behaviour observed in earlier laboratory studies. Complementary evidence was obtained on the behaviour called flick, which is sometimes inserted at the end of the static display phase, and may be viewed as an equivalent behaviour to the retreat display of the other small-bodied newt species. Sexual interference in the natural population was mainly caused by males. Two characteristic male behaviour patterns were recognised, the waiting position and the push-tail. Females tend to withdraw from situations of interference. Courtship sequences solely consisting of orientation and spermatophore transfer phases, so-called short-circuit sequences, may be interpreted as a male strategy to avoid the very severe male-to-male interference that exists in a wild population.

THE SOCIAL COSTS OF OBESITY: A NON-REACTIVE FIELD STUDY

1980 ◽  
Vol 8 (1) ◽  
pp. 91-96 ◽  
Author(s):  
Peter L. Benson ◽  
Drew Severs ◽  
John Tatgenhorst ◽  
Nancy Loddengaard
Keyword(s):  
Public Health ◽  
Field Study ◽  
Graduate School ◽  
Social Costs ◽  
The Other ◽  
Cover Letter ◽  
The Social ◽  
Reactive Field ◽  
Health Administrators ◽  
Field Setting

The major purposes of this study were to investigate whether devaluation of obese persons, a phenomenon demonstrated exclusively in laboratory settings using reactive measures, generalizes to a nonreactive field setting. Seventy public health administrators were asked, via the mail, to help a college junior assess her chances of getting into graduate school and finding employment in this field. Subjects received a cover letter, a standard résumé∼, and a questionnaire. A picture of the student was affixed to some of the résumés. Subjects were randomly assigned to one of three picture conditions: obese, normal, or no picture. Forty-six percent of the questionnaires were returned. Significantly fewer forms were returned in the obese condition than in the normal and no picture conditions. On both the graduate school and employment questionnaire items, forecasts were considerably more pessimistic than in the other two picture conditions. Implications of these findings are discussed.

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