Allelopathic and autotoxic interactions in selected populations of Loliumperenne grown in monoculture and mixed culture

2002 ◽  
Vol 29 (12) ◽  
pp. 1465 ◽  
Author(s):  
Edwin Kraus ◽  
Margje Voeten ◽  
Hans Lambers
Keyword(s):  
Mixed Culture ◽  
Biomass Allocation ◽  
Dark Respiration ◽  
Total Yield ◽  
The Other ◽  
Leaf Dark Respiration ◽  
Short And Long Term ◽  
Allelopathic Effects ◽  
Two Populations

Autotoxicity and allelopathy affect the respiration and yield of GL66 and GL72, two populations of perennial ryegrass (Lolium perenne L. cv. S23) that were originally selected for contrasting rates of mature-leaf dark respiration under conditions where allelopathic effects could not occur and autotoxic effects were minimal. The aim of this study was to further investigate growth and biomass allocation of these two populations in relation to their autotoxic and allelopathic properties. To this end, plants were subjected to two conditions (monoculture and mixed culture) and two treatments (growth in 'renewed' and 'replenished' nutrient solution, allowing for short- and long-term accumulation of allelochemicals, respectively). The fast-respiring population, GL66, showed a reduced total yield due to allelopathic effects only when long-term accumulation of allelochemicals was allowed (mixed culture, replenished). However, short-term accumulation (mixed culture, renewed) of allelochemicals was sufficient to affect allocation of biomass to leaf sheaths. The slow-respiring population, GL72, suffered from autotoxicity only when long-term accumulation was allowed (monoculture, replenished), and from allelopathy under both short- and long-term accumulation (mixed culture, either renewed or replenished). The predominant allelopathic and autotoxic effect was on dry matter percentage and dry weight of leaf sheaths. We conclude that the roots of both populations release one or more chemical compounds that primarily affect biomass allocation to leaf sheaths, both of the same and of the other population. Sensitivity to the putative inhibitor(s) released by the other population was greater than sensitivity to the inhibitor(s) released by a population's own roots.

scholarly journals The Pice Effects of Competition from Parallel Imports and Therapeutic Alternatives: Using Dynamic Models to Estimate the Causal Effect on the Extensive and Intensive Margins

2021 ◽  
Author(s):  
David Granlund
Keyword(s):  
Dynamic Models ◽  
Causal Effect ◽  
The Other ◽  
Causal Effects ◽  
Parallel Imports ◽  
Extensive And Intensive Margins ◽  
Price Effects ◽  
Short And Long Term ◽  
Therapeutic Alternatives

AbstractThis paper studies responses to competition with the use of dynamic models that distinguish between short- and long-term price effects. The dynamic models also allow lagged numbers of competitors to become valid and strong instruments for the current numbers, which enables studying the causal effects using flexible specifications. A first parallel trader is found to decrease prices of exchangeable products by 7% in the long term. On the other hand, prices do not respond to the first competitor that sells therapeutic alternatives; but competition from four or more competitors that sell on-patent therapeutic alternatives decreases prices by about 10% in the long term.

Polyacrilonytrile versus Cuprophan Membranes for Hemodialysis: Evaluation of Efficacy and Biocompatibility by Platelet Aggregation Studies

1981 ◽  
Vol 4 (5) ◽  
pp. 218-222 ◽  
Author(s):  
M. Berrettini ◽  
U. Buoncristiani ◽  
P. Parise ◽  
E. Ballatori ◽  
G.G. Nenci
Keyword(s):  
Platelet Count ◽  
Platelet Aggregation ◽  
Term Effect ◽  
The Other ◽  
Long Term Effect ◽  
Short And Long Term ◽  
Extracorporeal Dialysis ◽  
Uremic Patients

The short- and long-term effect of hemodialysis with two different membranes — cuprophan and polyacrilonytrile — on platelet aggregation has been investigated in 12 uremic patients undergoing extracorporeal dialysis, passing from one treatment to the other. Cuprophan membranes failed to correct the defective platelet aggregation of uremia, and their thrombogenicity was documented by a fall in platelet count and further impairment of platelet aggregation during dialysis. On the contrary, polyacrilonitryle membranes showed the capacity to correct completely but transiently the platelet aggregation, without changes in platelet count. The results indicate that polyacrilonytrile membranes show a better biocompatibility toward platelets than cuprophan membranes.

scholarly journals The Self, the Other, and the International Student

2016 ◽  
Vol 6 (1) ◽  
pp. 314-318
Author(s):  
David Starr-Glass
Keyword(s):  
International Students ◽  
Social Exchange ◽  
International Student ◽  
The Self ◽  
The Other ◽  
Critical Element ◽  
Georg Simmel ◽  
Cultural Alienation ◽  
Short And Long Term

A sense of strangerhood, which is different from social isolation or cultural alienation, is common among many of the international students whom I encounter. In a world increasingly preoccupied with personal interaction and social exchange, many of these students perceive strangerhood as problematic and inherently negative. This brief reflection considers strangerhood from the perspective of Georg Simmel and argues that being a stranger has considerable positive value. Recognition of strangerhood is a critical element in developing a greater understanding of both the self and the Other. Legitimizing the experience of strangerhood, emphasizing its potential value, and empowering students to embrace it may provide significant short- and long-term benefits for international students in their personal and transformative journeys.

scholarly journals Pembelajaran Kosa Kata Bahasa Arab Secara Aturan Kluster Semantik dan Aturan Kluster Bebas

2014 ◽  
Vol 67 (1) ◽  
Author(s):  
Nik Mohd Rahimi ◽  
Zahriah Hussin ◽  
Wan Normeza
Keyword(s):  
Arabic Language ◽  
The Other ◽  
Short Term ◽  
Test Analysis ◽  
Semantic Clustering ◽  
Short Term Test ◽  
Post Test ◽  
Quasi Experimental ◽  
Short And Long Term

Many Arabic language books use semantic clustering in presenting their vocabularies. However, some language experts suggest the use of semantically unrelated clustering due to a higher contribution in memorizing vocabularies among students. This study aims to investigate on which clustering has a higher contribution in memorizing vocabularies among students. The specific objectives of this study are; (a) to identify the level of students’ achievement in memorizing vocabularies using both techniques in a long-term test and a short-term test; and (b) to identify students’ achievement differences using both techniques in both tests. This study is a quasi-experimental study which using a short term and a long term post-test. This group of students was exposed to vocabularies using semantic clustering and semantically unrelated clustering. The short term post test was administered after the students were exposed with both techniques, while the long term post-test was used after seven days of the exposure. This study found that students’ achievement using semantic clustering was moderate for both tests. Meanwhile, students’ achievement using semantically unrelated clustering was very good in the short term test and good in the long term test. On the other hand, the t-test analysis showed that there are significant differences between both techniques, which students’ achievement using semantically unrelated clustering is statistically and significantly higher than students’ achievement using semantic clustering for both short and long term post-tests. Therefore, this study suggests that the semantically unrelated clustering technique needs to be used in learning Arabic vocabularies among students. 

scholarly journals Short- and long-term memory and age in a traditional tribe (Dani of Papua) and a modern population (Poland)

2020 ◽  
Vol 23 (3) ◽  
pp. 135-142
Author(s):  
Agnieszka Sabiniewicz ◽  
Maciej Karwowski ◽  
Corinna E. Löckenhoff ◽  
Barbara Borkowska ◽  
Piotr Sorokowski
Keyword(s):  
Reading Ability ◽  
Short Term Memory ◽  
Memory Performance ◽  
Long Term Memory ◽  
Age Difference ◽  
Term Memory ◽  
Technical Developments ◽  
Short And Long Term ◽  
Two Populations

Abstract The different environmental conditions in which people live might challenge memory in different ways. Moreover, the frequency of usage can be a source of improvement of both short- and long-term memory. The aim of our study was to investigate the effects of environmental differences on short- and long-term memory in a traditional versus a contemporary population (Dani of Papua, n = 62; Polish, n = 134). We found that both short- and long-term memory varied in the two populations, living in totally distinct surroundings. However, there were no age differences between Polish and Dani participants in either short- or long-term memory tasks, indicating that culture was not a significant moderator of the memory differences between populations. The differences in short- and long-term memory between the two populations are consistent with the argument that short-term memory plays a more significant role in contemporary societies because of technical developments, the electronic revolution, and reading ability. The lack of an age difference appears to support the assumption that it is age, not culture, that plays a crucial role in the memory performance.

Under pressure: Short‐ and long‐term response to predation varies in two populations of a live‐bearing fish

Ethology ◽  
2019 ◽  
Vol 126 (4) ◽  
pp. 463-475
Author(s):  
Eve A. Humphrey ◽  
Erica Crespi ◽  
Joseph Travis
Keyword(s):  
Short And Long Term ◽  
Two Populations ◽  
Term Response

Long-term population dynamics of Aphelenchoides besseyi on Oryza sativa in a paddy field, and changes in the pathological and ecological traits of the two populations

Nematology ◽  
2021 ◽  
pp. 1-17
Author(s):  
Shigeru Hoshino ◽  
Katsumi Togashi
Keyword(s):  
Population Dynamics ◽  
Oryza Sativa ◽  
The Other ◽  
Ecological Traits ◽  
Reproduction Curve ◽  
Aphelenchoides Besseyi ◽  
The Mean ◽  
Two Peaks ◽  
Two Populations

Summary An Oryza sativa cultivar inoculated with the white tip nematode, Aphelenchoides besseyi, was cultivated over 18 years to investigate the population dynamics of the nematode and the change in the virulence of nematodes and tolerance/resistance of plants. The mean number of living nematodes per seed (S) showed two peaks, each of which was followed by a 3-year decrease in the S value, during the initial 10 years. The annual reproduction curve between in year and in year t had a peak in a range of of <1.1. The incidence of white tip disease increased with increasing mean number of living nematodes seed−1 in the previous year, whereas the proportion of seeds with living nematodes increased with increasing mean number of living nematodes seed−1 in the current year. Inoculation tests of the nematode cohorts on the seedling cohorts derived from seeds harvested in the same or different years indicated that the initial 6-year interaction between the rice and nematode populations caused the nematodes to increase the incidence of white tip disease and to decrease the degree of seed swelling and the proportion of heavy seeds. On the other hand, the interaction caused the rice plants to prevent the incidence of disease from increasing and the degree of seed swelling and the proportion of heavy seeds from decreasing.

Impact on Short and Long-Term Hematopoiesis of G-CSF Administered Posttransplant in Function of the Amounts of Peripheral Blood CD34+38− Cells Reinfused.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 5197-5197
Author(s):  
Philippe R.G. Henon ◽  
Hanna Sovalat ◽  
Mario Ojeda-Uribe ◽  
Yazid Arkam ◽  
Jean-Claude Eisenmann
Keyword(s):  
Group Iv ◽  
The Other ◽  
Group Iii ◽  
Peripheral Blood Cd34 ◽  
Group I ◽  
Cd34 Cells ◽  
Autologous Pbsct ◽  
Short And Long Term ◽  
A Prospective Study

Abstract We previously suggested that a reinfused threshold dose of CD34+38− cells = 5x104/kg b.w. better predict both short- and long-term engraftment after PBSCT than total CD34+ cells assessment, and should thus avoid unecessary postransplant (Tx) G-CSF administration. Therefore, we have further conducted a prospective study comparing postTx data from cancer patients undergoing autologous PBSCT and were administered or not G-CSF depending on the amount of CD34+38− cells reinfused. 48 patients (mean age 49y) were transplanted with, on average 2.5x104 CD34+38− cells/kg b.w. (range 1–49) and were consequently administered G-CSF 5 μg/kg daily from d5 to ANC = 109/1 (Group-I). 46 patients (mean age 50y) received an average of 20.5x104 CD34+38− cells/kg (range 5.5–162) without postTx G-CSF (Group-II). These 2 groups were compared and paired two by two with 2 groups of "historical" patients referred as controls : 11 patients (mean age 44y) had received, on average, 2.5x104 CD34+38− cells/kg b.w. (range 1.1–4.8) without G-CSF (Group-III); 29 patients (mean age 51y) received an average of 15.2x5x104 CD34+38− cells/kg b.w. (range 5.5–60) systematically associated with G-CSF for protocolar reasons (Group-IV). PostTx trilineage hematopoietic engraftment (up to 2 years), clinical and economical parameters were systematically recorded for each group of patients and statistically compared. PostTx ANC recovery occurred sooner, was faster and reached higher levels in the G-CSF groups (II and IV) compared to the others; platelets recovery kinetics was significantly faster in Group-III compared to the others; reticulocytic recovery was not statistically different whichever the group. When age, sex, disease, TBI did not significantly influence trilineage engraftment, a multiparametric study showed strong positive impacts of total CD34+ cells reinfused on ANC kinetics and of CD38− subset amounts on platelet kinetics, which was on the contrary slowered by G-CSF administration. Group-I patients received more transfusions, stayed longer hospitalized and costed more than those of the 3 other groups. Regarding long-term hematopoiesis, platelets and hemoglobin levels were globally higher in Group-III compared to the other groups, but still more dramatically compared to Group-IV from 1 to 9 months, which might be explained by differences in BM CD34+ and 38− subset differentiation. In conclusion, if postTx G-CSF certainly accelerates ANC recovery, it seems to be to the detriment of short- an d median-term platelets and hemoglobin recovery, even in case of reinjection of CD34+38− cell doses = 5x104/kg b.w., which appears thus to be significantly discriminant for G-CSF administration decision.

Immediate, short- and long-term opposite effects of oestradiol-17β on glucose metabolism in rat adipocytes: relationship with the biphasic changes in body weight and food intake

1984 ◽  
Vol 101 (1) ◽  
pp. 13-19 ◽  
Author(s):  
A. Faure ◽  
M.-Th. Vergnaud ◽  
M.-Th. Sutter-Dub ◽  
B. Ch. J. Sutter
Keyword(s):  
Body Weight ◽  
Food Intake ◽  
Glucose Oxidation ◽  
The Other ◽  
Ovariectomized Rats ◽  
Insulin Effect ◽  
Short And Long Term ◽  
Dramatic Fall

ABSTRACT The changes in the effects of oestradiol-17β on body weight, food intake and [1-14C]glucose oxidation in adipocytes were followed in sham-operated, ovariectomized and adrenalectomized–ovariectomized rats to eliminate effects of endogenous progesterone and corticosterone. During the first 5 days oestradiol induced a dramatic fall in food intake and body weight concomitant with a decrease in glucose oxidation by adipocytes, when tested 12 h and 3 days after the beginning of treatment. In-vitro incubations with oestradiol showed that this was a direct effect of this hormone. On the other hand, from days 5 to 14 of treatment, body weight and food intake increased, though they were still lower than in sham-operated controls. On day 14, as values of treated rats tended to reach those of controls, glucose oxidation in adipocytes was stimulated by oestradiol treatment. An insulin effect was still observable and none of these effects was dependent on the adrenal gland. These biphasic changes in the parameters studied could be closely related; moreover, a relationship with other oestradiol actions on metabolism that are known to be corticosterone-dependent could be eliminated. J. Endocr. (1984) 101, 13–19

scholarly journals Revealing asymmetric spillover effects in hazelnut, gasoline, and exchange rate markets in Turkey: The VECM-BEKK-MGARCH approach

2020 ◽  
pp. 5-5
Author(s):  
Emine Askan ◽  
Faruk Urak ◽  
Abdulbaki Bilgic
Keyword(s):  
Exchange Rates ◽  
Granger Causality ◽  
Spillover Effects ◽  
Statistical Testing ◽  
The Other ◽  
Causality Tests ◽  
Short And Long Term ◽  
Exchange Rate Markets ◽  
Two Sectors

The study used the VECM-BEKK-MGARCH method to model the volatility transmission between the markets of gasoline, exchange rates, and the hazelnut market for the period of 21.07.2005-20.3.2018. The suitability of the VECM-BEKK-MGARCH method was confirmed by statistical testing. The changes in hazelnut prices were not affected by the changes in the prices or final values in the other two sectors (Granger causality). Moreover, the Granger causality tests revealed that, while the change in the gasoline market was not affected by the other two markets, the change in the exchange rates market was affected by the other two markets. Furthermore, especially the volatilities (long-term uncertainties) of the markets were affected by both their own short- and long-term volatilities and other sectors? short- and long-term volatilities. It was shown that the long-term swings in these three markets were affected by the cross-interaction in the markets. Additionally, as opposed to the case in the positive news, it was observed that pieces of negative news about the markets affected the markets.

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