Asymptotic line-of-descent distributions

1984 ◽  
Vol 21 (1) ◽  
pp. 67-75 ◽  
Author(s):  
R. C. Griffiths
Keyword(s):  
2018 ◽  
Vol 54 (No. 2) ◽  
pp. 74-82
Author(s):  
Minyaka Emile ◽  
Banen Collette Vanessa Madina ◽  
Kusznierewicz Barbara ◽  
Doungous Oumar ◽  
Haouni Soungouna ◽  
...  

A new strategy to reduce the severity of black pod disease (BPD) in T. cacao plants using MgSO<sub>4</sub> nutrition was investigated. The dynamics of the tolerance to BPD of 18 susceptible T. cacao plantlets coming from the cross (♀SNK64 × ♂UPA14) was monitored during weekly (8 weeks) supply of MgSO<sub>4</sub> into the soil. Prior to MgSO<sub>4</sub> application, disease scores of the 18 plantlets (in six sets of three plantlets per set) were varying between 3.5 (susceptible) and 5 (highly susceptible). After MgSO<sub>4 </sub>application, a substantial decrease in disease scores was observed compared to the control. The percentage of disease tolerance gain of plantlets versus MgSO<sub>4</sub> supplied (0–2.96 g) presented a quasi-hyperbolic curve with asymptotic line corresponding to 60% (day 28) and 70% (day 56). Cysteine content was not significantly different between the six triplets before MgSO<sub>4 </sub>nutrition. On days 28 and 56 of MgSO<sub>4</sub> supplementation, cysteine content presented a pattern similar to the tolerance gain of plantlet sets. The monitoring of glutathione content versus MgSO<sub>4</sub> supplementation (compared to day 0) showed sigmoid (day 28) and hyperbolic (day 56) curves which were associated with defined mathematical laws determined by MALAB software. Negative and highly significant correlations were observed between disease scores, cysteine and glutathione contents in leaves while positive and highly significant correlations were observed between cysteine and glutathione contents in leaves. These data might mean that MgSO<sub>4</sub> nutrition significantly improved the tolerance of T. cacao. The mechanism of tolerance improvement might be associated with the synthesis of sulphur-containing compounds (cysteine and glutathione) which might be directly or indirectly used by T. cacao against P. megakarya.


Author(s):  
A.G. CORBALAN ◽  
M. MAZON ◽  
T. RECIO

In this paper we study some unexpected geometric properties of the family of bisector lines for a convex distance d, showing that bisectors do not always have an asymptotic line (Section 2). Moreover, although bisectors are homeomorphic to lines, pairs of them can exist intersecting infinitely many times (Section 3). This leads to the conclusion that convex distances are not always nice in the sense of Klein and Wood.7 On the other hand, we prove that distances d, having d-balls whose boundary is given by finitely many algebraic conditions, produce nice distances (Section 3).


2013 ◽  
Vol 168 (1) ◽  
pp. 265-289 ◽  
Author(s):  
Emanuel Huhnen-Venedey ◽  
Thilo Rörig

KoG ◽  
2021 ◽  
pp. 78-86
Author(s):  
Ana Katalenić ◽  
Aleksandra Čižmešija ◽  
Željka Milin Šipuš

In this paper we present a review of the basic ideas and results concerning asymptotic lines of plane curves. We discuss their different definitions, namely that of a limiting position of tangent lines, of the tangent line at infinity, and finally the one that requires that the distance between points of a curve and asymptotic line tends to 0 as the point moves along an infinite branch of the curve. We also recall the method of determining asymptotes of algebraic curves from the leading coefficients in their equation and provide examples.


2019 ◽  
Vol 72 (12) ◽  
pp. 817-824 ◽  
Author(s):  
Masatoshi Wakui ◽  
Yuta Fujimori ◽  
Shoko Nakamura ◽  
Yoshino Kondo ◽  
Yuko Kuroda ◽  
...  

AimsBivalent direct thrombin inhibitors (DTIs), hirudin and bivalirudin, bind to the active site and exosite 1 of thrombin irreversibly and reversibly, respectively. The present study aims to assess in vitro effects of hirudin and bivalirudin through clot waveform analysis (CWA) and enzyme kinetics in coagulation assays.MethodsThe pooled normal plasma and its dilutions were spiked with hirudin or bivalirudin. The activated partial thromboplastin time (APTT) assay and the Clauss fibrinogen assay were performed using the CS-5100 (Sysmex). The APTT-CWA data were automatically gained by the CS-5100 programme.ResultsIn APTT-CWA, the maximum coagulation velocity, acceleration and deceleration were decreased dependently on the drug concentrations, demonstrating evidence for the blockade of thrombin-positive feedback by hirudin or bivalirudin. The Hill plot analysis was applied to the dose-dependent curves in bivalirudin. The Hill coefficients were greater than 1, showing positive anticoagulant cooperativity. Regarding the dose-dependent curves in hirudin, all the parameters dropped to almost zero without making an asymptotic line. In the Clauss fibrinogen assay, the Lineweaver-Burk plots demonstrated that both drugs exhibit mixed inhibition mimicking uncompetitive binding. The Dixon plots in bivalirudin were linear and supported the inhibition type described above. The Dixon plots in hirudin were non-linear and inappropriate to use for determination of the inhibition type. In addition, the inverse function of the clotting time appeared to drop to zero without making an asymptotic line, suggesting complete loss of thrombin activity by irreversible binding.ConclusionsThe results provide insights into anticoagulation with bivalent DTIs.


2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Nidal Echabbi ◽  
Amina Ouazzani Chahdi

In this work, we consider the Darboux frame T , V , U of a curve lying on an arbitrary regular surface and we construct ruled surfaces having a base curve which is a V -direction curve. Subsequently, a detailed study of these surfaces is made in the case where the directing vector of their generatrices is a vector of the Darboux frame, a Darboux vector field. Finally, we give some examples for special curves such as the asymptotic line, geodesic curve, and principal line, with illustrations of the different cases studied.


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