Vertical clinging and leaping revisited: Vertical support use as the ancestral condition of strepsirrhine primates

2011 ◽  
Vol 146 (3) ◽  
pp. 323-335 ◽  
Author(s):  
Daniel L. Gebo
Keyword(s):  
Ancestral Condition ◽  
Vertical Support

The cytotaxonomy of three species in the jenningsi-group of the subgenus Simulium (Diptera: Simuliidae) in New York State

1984 ◽  
Vol 62 (3) ◽  
pp. 347-354 ◽  
Author(s):  
A. Elizabeth Gordon
Keyword(s):  
New York ◽  
Sex Determination ◽  
Sibling Species ◽  
New York State ◽  
York State ◽  
Ancestral Condition ◽  
Finger Lakes ◽  
Finger Lakes Region

The chromosomal constitutions of three species in the jenningsi-group in the Adirondacks and the Finger Lakes Region in New York State are detailed. No sibling species were found in Simulium jenningsi, S. fibrinflatum, or S. luggeri in these areas. The species were found to differ by 6 fixed inversions and by 19 floating inversions. 4 of which are related to sex determination in S. jenningsi. The major chromosomal differences between the venustutm-group and the jenningsi-group are detailed. The ancestral condition for each arm was determined using ex-group and L′ analyses. A phylogenetic sequence for these three species from the ancestral condition is proposed.

A Comparative Study of Trichomes in Angophora Cav. And Eucalyptus L'hérit. - A Question of Homology

1984 ◽  
Vol 32 (5) ◽  
pp. 561 ◽  
Author(s):  
PY Ladiges
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Comparative Study ◽  
Light Microscopy ◽  
Evolutionary Trends ◽  
Oil Glands ◽  
Ancestral Condition ◽  
Scanning Electron

The trichomes of Angophora and Eucalyptus are illustrated from scanning electron microscopy and light microscopy, and evolutionary trends are discussed. Bristle glands of Angophora and Eucalyptus subgen. Blakella and Corymbia are emergent oil glands of varying lengths. Emergent oil glands occur in all other Eucalyptus subgenera but they are most conspicuous in Blakella, Corymbia and Angophora, in which they are characterized by four cap cells each ornamented with micropapillae. Hairs in Angophora are unique, being multicellular; they are also uniseriate and scattered on the epidermis. In contrast, hairs in Eucalyptus are simple extensions, short or long, of the cells on the sides of or the cap cells of the emergent oil glands, and they are not homologous with those of Angophora. Eucalyptus setosa (subgen. Blakella) and E. brockwayi (subgen. Symphyomyrtus) are two exceptions, having unicellular hairs on the epidermis, not associated with oil glands. It is suggested that this is an ancestral condition (or secondary reversal to it).

The enigmatic diapsid Acerosodontosaurus piveteaui (Reptilia: Neodiapsida) from the Upper Permian of Madagascar and the paraphyly of “younginiform” reptiles

2009 ◽  
Vol 46 (9) ◽  
pp. 651-661 ◽  
Author(s):  
Constanze Bickelmann ◽  
Johannes Müller ◽  
Robert R. Reisz
Keyword(s):  
Phylogenetic Analysis ◽  
Data Matrix ◽  
Upper Permian ◽  
Phylogenetic Position ◽  
Ancestral Condition ◽  
Phylogenetic Data ◽  
First Time ◽  
Evolutionary Lineages

A restudy of the Upper Permian diapsid Acerosodontosaurus piveteaui from Madagascar indicates that the bone formerly identified as the quadratojugal is a fragment of a rib. This in turn implies that, in contrast to previous studies, the lower temporal arcade must be considered incomplete and derived relative to the ancestral condition. Since the phylogenetic position of Acerosodontosaurus is poorly understood, the taxon was entered into a modified phylogenetic data matrix of diapsid reptiles, and the purported monophyly of “Younginiformes” was tested for the first time by including all potential members of the clade as separate taxa, as well as other taxa from the same deposits. The results of the phylogenetic analysis do not support the monophyly of “younginiform” reptiles. Instead, most taxa cluster unresolved at the base of Neodiapsida, a finding that has important implications for the understanding of early diapsid evolution because it suggests that early neodiapsids represent several distinct evolutionary lineages. Acerosodontosaurus and Hovasaurus do form a clade, a finding consistent with the stratigraphic age and biogeography of these taxa.

Simulation-Guided Stimulation for Paretic Ankle Muscles During Stroke Gait

2007 ◽  
Author(s):  
J. Higginson ◽  
T. Kesar ◽  
R. Perumal ◽  
S. Binder-Macleod
Keyword(s):  
Neuronal Damage ◽  
Center Of Mass ◽  
Knee Extensors ◽  
Muscle Coordination ◽  
Hemiparetic Gait ◽  
Ankle Muscles ◽  
Vertical Support ◽  
The Brain ◽  
The U.S

Stroke is the leading cause of long-term adult disability in the U.S. Neuronal damage in the brain results in impaired muscle coordination which induces asymmetric and abnormal walking patterns. Muscle-actuated forward dynamic simulation of walking patterns of healthy young adults has elucidated unique and synergistic roles of the uniarticular and biarticular plantarflexors. Neptune and colleagues (2001) reported that soleus delivers energy to the trunk, gastrocnemius accelerates the leg forward, and both contribute significantly to vertical support of the center of mass [1]. In a simulation of post-stroke hemiparetic gait, Higginson et al. (2006) observed that non-paretic muscles mimicked the function of healthy muscles, while paretic ankle plantarflexor function was limited and required supplemental effort by hip and knee extensors [2].

A phylogenetic perspective on absence and presence of a sex-limited polymorphism

2008 ◽  
Vol 58 (2) ◽  
pp. 257-273 ◽  
Author(s):  
Michelle. Mattern ◽  
Hans Van Gossum
Keyword(s):  
Mating System ◽  
North American ◽  
Phylogenetic Trees ◽  
Evolutionary Perspective ◽  
Ancestral Condition ◽  
End Point ◽  
Subsequent Loss ◽  
Phylogenetic Perspective

AbstractSex-limited polymorphism is widely distributed among animal taxa, but has only rarely been studied from a macro-evolutionary perspective. We investigate the evolution of female-limited polymorphism by mapping presence or absence of multiple discrete morphs on published phylogenetic trees for North American representatives of two damselfly genera. The results indicate that female polymorphy represents the ancestral condition based on the species included with subsequent loss and monomorphy representing the evolutionary end-point in most cases. According to one phylogeny, character optimization suggests that expression of the polymorphism may be lost (to a state of monomorphy) and gained again (back to polymorphy). Earlier work indicated that changes from polymorphy to monomorphy might be coupled with evolution of the mating system from polyandry to monandry. The results presented here, however, do not convincingly support such view.

Effect of vertical support on highway bridge superstructures

1991 ◽  
Vol 40 (4) ◽  
pp. 947-955
Author(s):  
J.S. Davidson ◽  
C.H. Yoo
Keyword(s):  
Highway Bridge ◽  
Bridge Superstructures ◽  
Vertical Support

Analysis of Global Stability, Anchor Spacing, and Support Cable Loads in Wire Mesh and Cable Net Slope Protection Systems

2005 ◽  
Vol 1913 (1) ◽  
pp. 205-213 ◽  
Author(s):  
Navaratnarajah Sasiharan ◽  
Balasingam Muhunthan ◽  
Shanzhi Shu ◽  
Thomas C. Badger
Keyword(s):  
Numerical Models ◽  
Wire Mesh ◽  
System Failures ◽  
Design Elements ◽  
The Past ◽  
Protection Systems ◽  
Vertical Support ◽  
Stability Of Slope ◽  
The Stability ◽  
Horizontal Support

Wire mesh and cable net slope protection have been in use for more than 50 years along North American highways to control rockfall on actively eroding slopes. The basic design of these systems is comparatively similar throughout North America. It consists of a top horizontal cable suspended by regularly spaced anchors, typically a perimeter or widely spaced grid of horizontal and vertical support cables, and double-twisted, hexagonal wire mesh laced to the support ropes. To date, the design of the slope protection systems has been based primarily on empirical methods, engineering judgment, and experience. Although these systems generally perform well, there is some consensus among geotechnical specialists that some elements in the system may be overdesigned or even unnecessary. In addition, system failures under a variety of loading conditions within the past few decades indicate that certain design elements may in fact be underdesigned for their desired application. Analytical and numerical models to evaluate the stability of slope protection systems are presented. The inclusion of interior horizontal support ropes in addition to the top horizontal rope does not reduce the stress within the mesh and accordingly provides no mechanical benefit. Results also show that the stresses on the vertical support rope are much smaller than the top horizontal support rope. Therefore, the vertical ropes do not need to be as strong as the top horizontal rope. Further, some useful design charts for the design of slope protection system are presented.

scholarly journals The CESuRa System: Allowing Changes in a Rail Track Profile While Maintaining Full Vertical Support

2018 ◽  
Vol 4 (4) ◽  
pp. 198-210
Author(s):  
Andy Foan ◽  
Travis Thonstad ◽  
John F. Stanton
Keyword(s):  
Rail Track ◽  
Vertical Support
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