Maintenance of sympatric floral tube-length variation in a Cape irid

2011 ◽  
Vol 104 (1) ◽  
pp. 129-137 ◽  
Author(s):  
PETRA ROS ◽  
ALLAN G. ELLIS ◽  
BRUCE ANDERSON
Keyword(s):  
Tube Length ◽  
Length Variation ◽  
Floral Tube

scholarly journals Intraspecific divergence and convergence of floral tube length in specialized pollination interactions

2014 ◽  
Vol 281 (1795) ◽  
pp. 20141420 ◽  
Author(s):  
B. Anderson ◽  
P. Ros ◽  
T. J. Wiese ◽  
A. G. Ellis
Keyword(s):  
Linear Relationship ◽  
Floral Morphology ◽  
Population Level ◽  
Tube Length ◽  
Length Variation ◽  
Positive Linear Relationship ◽  
Intraspecific Divergence ◽  
Floral Tube ◽  
Adaptive Specialization ◽  
Pollinator Fauna

Floral tubes are often thought to be a consequence of adaptive specialization towards pollinator morphology. We explore floral tube length evolution within Tritoniopsis revoluta (Iridaceae), a species with considerable geographical tube length variation. We ask whether tube lengths of T. revoluta populations are associated with pollinator proboscis lengths, whether floral divergence occurs in the presence of different pollinators and whether floral convergence occurs between distantly related populations pollinated by the same pollinator. Finally, we ask whether tube length evolution is directional. Shifts between morphologically different pollinators were always associated with shifts in floral morphology, even when populations were very closely related. Distantly related populations had similar tube lengths when they were pollinated by the same pollinator. Shifts in tube length tended to be from short to long, although reversals were not infrequent. After correcting for the population-level phylogeny, there was a strong positive, linear relationship between floral tube length and pollinator proboscis length, suggesting that plants are functionally specialized on different pollinators at different sites. However, because tube length evolution in this system can be a bidirectional process, specialization to the local pollinator fauna is unlikely to result in evolutionary or ecological dead-ends such as canalization or range limitation.

scholarly journals Diurnal hawk moth pollination of Melampyrum koreanum (Orobanchaceae) and the origin of this endemic Korean species

Phytotaxa ◽  
2014 ◽  
Vol 172 (1) ◽  
pp. 31 ◽  
Author(s):  
Sangjin Jo ◽  
Dong-Keun Yi ◽  
Ki-Joong Kim
Keyword(s):  
Host Plant ◽  
Pinus Thunbergii ◽  
Tube Length ◽  
Pollination Syndrome ◽  
Endemic Plant ◽  
Floral Tube ◽  
Hawk Moth ◽  
Moth Pollination ◽  
Conservation Plan ◽  
Strong Candidate

Melampyrum koreanum (Orobanchaceae) was described recently as an endemic species in Korea. This study examined the distribution range, relationship with the host plant, flower developmental pattern, pollinator, pollination mechanism, and seed development of M. koreanum (Orobanchaceae) on the island of Somaemul-do, Korea. M. koreanum is hemiparasitic and a strong candidate for its host plant is Pinus thunbergii, with which it is distributed sympatrically. The flower of M. koreanum represents a typical hawk moth pollination syndrome. Macroglossum pyrrhostictum Butler (Sphingidae, Lepidoptera), a diurnal hawk moth, is the only efficient pollinator. The proboscis length of M. pyrrhostictum and the floral tube length of M. koreanum are well coordinated, and the positions of the anther and stigma of M. koreanum are mechanically conformed to hawk moth pollination. The results suggest that adaptation to the pollinator is the main factor that has affected the evolution of the longer floral tube of M. koreanum compare to other species. Pollinator conservation in the native range of M. koreanum is an important issue for the conservation of endemic plant species, and it is necessary to establish a conservation plan for the host plant, Pinus thunbergii, as well as M. koreanum.

Intraspecific divergence in floral‐tube length promotes asymmetric pollen movement and reproductive isolation

2019 ◽  
Vol 224 (3) ◽  
pp. 1160-1170 ◽  
Author(s):  
Corneile Minnaar ◽  
Marinus L. de Jager ◽  
Bruce Anderson
Keyword(s):  
Reproductive Isolation ◽  
Tube Length ◽  
Intraspecific Divergence ◽  
Floral Tube ◽  
Pollen Movement

scholarly journals Pollination, mating and reproductive fitness in a plant population with bimodal floral-tube length

2016 ◽  
Vol 29 (8) ◽  
pp. 1631-1642 ◽  
Author(s):  
B. Anderson ◽  
A. Pauw ◽  
W. W. Cole ◽  
S. C. H. Barrett
Keyword(s):  
Reproductive Fitness ◽  
Plant Population ◽  
Tube Length ◽  
Floral Tube

Modulus of Elasticity of Elastic Tubes Used in Neuromuscular Rehabilitation Programs

2021 ◽  
pp. 1-6
Author(s):  
Andrea Lucena Reis ◽  
Thaís Lucena Reis ◽  
Lucas Soares de Aguiar ◽  
José de Jesus Soares Reis ◽  
Thiago Lucena Reis ◽  
...  
Keyword(s):  
Elastic Constant ◽  
Correlation Coefficient ◽  
Intraclass Correlation Coefficient ◽  
Coefficient Of Variation ◽  
Intraclass Correlation ◽  
Elastic Tube ◽  
Tube Length ◽  
Length Variation ◽  
Rehabilitation Programs ◽  
Elastic Tubes

Context: The elastic tubes have been used for clinical rehabilitation programs in which exercises are performed with submaximal intensities due to the difficulty in the measure the applied force. The authors aimed to quantify the elastic constant of elastic tubes used in neuromuscular rehabilitation programs predicting the force related to elastic tube elongation. A force test was performed by stretching the elastic tubes to determine the relationship between force and elongation. Eight elastic tubes with progressive levels of resistance represented by colors (yellow, red, blue, gray, black, grape, purple, and gold—low to higher resistance) were used. Design: Experimental. Methods: The test and retest were compared using the paired t test. The agreement and reliability between the test versus retest of pooled means colors were analyzed by plotting the Bland–Altman graph and intraclass correlation coefficient and the coefficient of variation. Pearson correlation was used to verify the validity between measurements. Results: The force values generated from the elastic tube elongation increase according to the color and thickness of elastic tubes with a strong and significant association between them (P < .0001). The elastic constant measurements were similar and presented high intraclass correlation coefficient values, low coefficient of variation values, and were reproducible (P < .0001). Conclusions: The force could be quantified according to elastic tube length variation by the linear regression equation with reproducibility. It gives greater measurement precision and better training load control when using elastic tubes in strength training programs.

scholarly journals Residual Stresses on Various PVD Hard Coatings on Tube and Plate Substrates

Coatings ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1054
Author(s):  
Harri Lille ◽  
Alexander Ryabchikov ◽  
Priidu Peetsalu ◽  
Liina Lind ◽  
Fjodor Sergejev ◽  
...  
Keyword(s):  
Residual Stresses ◽  
Rear Surface ◽  
Front Surface ◽  
Length Change ◽  
Hard Coatings ◽  
Wear Testing ◽  
Tube Length ◽  
Length Variation ◽  
Cross Sectional ◽  
Compressive Residual Stresses

In this study, the average residual stresses were determined in hard PVD nACRo (nc-AlCrN/a-Si3N4), nACo (nc-AlTiN/a-Si3N4), AlCrN, TiAlN, and TiCN commercial coatings through the deflection of the plate substrates and the simultaneous measurement of length variation in thin-walled tubular substrates. The length measuring unit was used for the measurement of any length change in the tubular substrate. A change in tube length was reduced to the deflection of the middle cross-section of the elastic element for which deformation was measured using four strain gauges. The cross-sectional microstructure and thickness of the coatings were investigated by means of scanning electron microscopy (SEM), and a determination was made of the chemical composition of the coatings and substrate by means of energy dispersive X-ray spectroscopy (EDS). The values of average compressive residual stresses, as determined by both methods, were very high (with a variation of between 2.05 and 6.63 GPa), irrespective of coating thickness, but were dependent upon the shape of the substrate and on its position in relation to the axis of the rotating cathode. The thicknesses of the coatings that were deposited on the plates with two parallel fixings (such as the nACRo coatings on the front surface at 6.8 μm and on the rear surface at 2.9 μm) and on the tubular substrates (10.0 μm) were significantly different. The higher average compressive residual stresses in the coating correlate to the higher average relative wear resistance that was obtained during field wear testing.

Dew Point Measurement Error due to Tube Length in a Calibration Instrumentation and the Evaluation of Measurement Uncertainty

2015 ◽  
Vol 789-790 ◽  
pp. 519-525
Author(s):  
Yun Kyung Bae ◽  
Dong Hoon Hyun
Keyword(s):  
Measurement Uncertainty ◽  
Moisture Absorption ◽  
International Standards ◽  
Dew Point ◽  
Tube Length ◽  
Length Variation ◽  
Point Temperature ◽  
Dew Point Temperature ◽  
Point Measurement ◽  
Uncertainty Source

The purpose of this paper is to analyze the effect of tube length in calibration instrumentation on dew point measurement of dew point sensors (DPS) and evaluation of measurement uncertainty. When measuring dew point temperature, various tube lengths between dew point generator and dew point sensor (DPS) cause a significant error due to moisture absorption of inner tube. The measurement is carried out to analyze the variation on measured dew point temperature for four cases of tube lengths with 300 mm, 1200 mm, 2500 mm and 5000 mm. The dew point temperature measurements were performed in the range from-60 °C to 10 °C by using calibrated standard chilled mirror hygrometer as reference standard. In order to investigate contribution to the standard uncertainty for the tube length variation as an uncertainty source, expanded uncertainties were evaluated for the cases including the effect of tube length variation as an uncertainty source and excluding it at each measurement point. The measurement was conducted according to standard calibration procedure of Korea Testing Laboratory which assures suitability and traceable results. It is also based on international standards.

On the Crystal Chemistry of Inorganic Nitrides: Crystal-Chemical Parameters and Opportunities in the Exploration of Their Compositional Space

2020 ◽  
Author(s):  
Olivier Charles Gagné
Keyword(s):  
Functional Properties ◽  
A Priori ◽  
Lone Pair ◽  
Length Variation ◽  
Electronic Effects ◽  
Statistical Knowledge ◽  
Redox Active ◽  
Multiply Bonded ◽  
Jahn Teller ◽  
Compositional Space

The scarcity of nitrogen in Earth’s crust, combined with challenging synthesis, have made inorganic nitrides a relatively-unexplored class of compounds compared to their naturally-abundant oxide counterparts. To facilitate exploration of their compositional space via <i>a priori</i> modeling, and to help <i>a posteriori</i> structure verification not limited to inferring the oxidation state of redox-active cations, we derive a suite of bond-valence parameters and Lewis-acid strength values for 76 cations observed bonding to N<sup>3-</sup>, and further outline a baseline statistical knowledge of bond lengths for these compounds. We examine structural and electronic effects responsible for the functional properties and anomalous bonding behavior of inorganic nitrides, and identify promising venues for exploring uncharted compositional spaces beyond the reach of high-throughput computational methods. We find that many mechanisms of bond-length variation ubiquitous to oxide and oxysalt compounds (e.g., lone-pair stereoactivity, the Jahn-Teller and pseudo Jahn-Teller effects) are similarly pervasive in inorganic nitrides, and are occasionally observed to result in greater distortion magnitude than their oxide counterparts. We identify inorganic nitrides with multiply-bonded metal ions as a promising venue in heterogeneous catalysis, e.g. in the development of a post-Haber-Bosch process proceeding at milder reaction conditions, thus representing further opportunity in the thriving exploration of the functional properties of this emerging class of materials.<br>

Sign in / Sign up

Export Citation Format

Share Document