scholarly journals What do we mean by the directions “cranial” and “caudal” on a vertebra?

2019 ◽  
Author(s):  
Michael P Taylor ◽  
Matthew J Wedel
Keyword(s):  
Spinal Column ◽  
Lateral View ◽  
Horizontal Axis ◽  
Neural Arch ◽  
Objective Measurements ◽  
Articular Surfaces ◽  
Neural Canal ◽  
Arch Neural

In illustrating vertebrae, it is important to consistently depict their orientation, so we can objectively assess and compare the slope of the neural arch, neural canal, or articular surfaces. However, differing vertebral shapes across taxa and across regions of the spinal column make it difficult to maintain consistency, or even define what we mean by the directions “cranial” and “caudal”. Consequently, characters such as “Neural arch slopes cranially 30° relative to the vertical” are disputable rather than objective measurements. Cranial and caudal are defined as directed along the horizontal axis, but several different notions of “horizontal” are possible: 1. Long axis of centrum is horizontal. This is appealing for elongate vertebrae such as sauropod cervicals, but is not always well defined, and is difficult to determine for craniocaudally short vertebrae such as most caudals. 2. Articular surfaces of centrum are vertical. Difficult to determine when dealing with facets that are concave or (worse) convex; and ambiguous for “keystoned” vertebrae in which the facets are not parallel. 3. Neural canal is horizontal. Anatomically informative, but difficult to determine in vertebrae that have not been fully prepared or CT-scanned, and impossible to see in lateral view. Ambiguous for vertebrae where the dorsal and ventral margins of the canal are not straight or not parallel. 4. Similarity in articulation (“horizontal” is defined as a line joining the same point on two similarly oriented copies of the same vertebra when optimally articulated). This is less intuitive than definitions 1–3, but takes the entire vertebra into account. We advocate explicitly stating a definition and using it consistently. In most cases, definition 3 (“Neural canal is horizontal”) best reflects anatomical and developmental realities, and it is therefore preferred. Low-tech techniques can be used to determine neural canal orientation with adequate precision for most purposes.

scholarly journals What do we mean by the directions “cranial” and “caudal” on a vertebra?

2019 ◽  
Author(s):  
Michael P Taylor ◽  
Matthew J Wedel
Keyword(s):  
Spinal Column ◽  
Lateral View ◽  
Horizontal Axis ◽  
Neural Arch ◽  
Objective Measurements ◽  
Articular Surfaces ◽  
Neural Canal ◽  
Arch Neural

In illustrating vertebrae, it is important to consistently depict their orientation, so we can objectively assess and compare the slope of the neural arch, neural canal, or articular surfaces. However, differing vertebral shapes across taxa and across regions of the spinal column make it difficult to maintain consistency, or even define what we mean by the directions “cranial” and “caudal”. Consequently, characters such as “Neural arch slopes cranially 30° relative to the vertical” are disputable rather than objective measurements. Cranial and caudal are defined as directed along the horizontal axis, but several different notions of “horizontal” are possible: 1. Long axis of centrum is horizontal. This is appealing for elongate vertebrae such as sauropod cervicals, but is not always well defined, and is difficult to determine for craniocaudally short vertebrae such as most caudals. 2. Articular surfaces of centrum are vertical. Difficult to determine when dealing with facets that are concave or (worse) convex; and ambiguous for “keystoned” vertebrae in which the facets are not parallel. 3. Neural canal is horizontal. Anatomically informative, but difficult to determine in vertebrae that have not been fully prepared or CT-scanned, and impossible to see in lateral view. Ambiguous for vertebrae where the dorsal and ventral margins of the canal are not straight or not parallel. 4. Similarity in articulation (“horizontal” is defined as a line joining the same point on two similarly oriented copies of the same vertebra when optimally articulated). This is less intuitive than definitions 1–3, but takes the entire vertebra into account. We advocate explicitly stating a definition and using it consistently. In most cases, definition 3 (“Neural canal is horizontal”) best reflects anatomical and developmental realities, and it is therefore preferred. Low-tech techniques can be used to determine neural canal orientation with adequate precision for most purposes.

scholarly journals What do we mean by the directions “cranial” and “caudal” on a vertebra?

2018 ◽  
Author(s):  
Michael P Taylor ◽  
Matthew J Wedel
Keyword(s):  
Spinal Column ◽  
Lateral View ◽  
Neural Arch ◽  
Objective Measurements ◽  
Articular Surfaces ◽  
Neural Canal ◽  
Arch Neural

In illustrating vertebrae, it is important to consistently depict their orientation, so we can objectively assess and compare the slope of the neural arch, neural canal, or articular surfaces. However, differing vertebral shapes across taxa and across regions of the spinal column make it difficult to maintain consistency, or even define what we mean by the directions “cranial” and “caudal”. Consequently, characters such as “Neural arch slopes cranially 30° relative to the vertical” are disputable rather than objective measurements. Cranial and caudal are defined as directed along the horizontal, but several different notions of “horizontal” are possible: 1. Long axis of centrum is horizontal. This is appealing for elongate vertebrae such as sauropod cervicals, but is difficult to determine for craniocaudally short vertebrae such as most caudals. 2. Articular facets of centrum are vertical. Difficult to determine when dealing with facets that are concave or (worse) convex; and ambiguous for “keystoned” vertebrae in which the facets are not parallel. 3. Neural canal is horizontal. Anatomically informative, but difficult to determine in vertebrae that have not been fully prepared or CT-scanned, and impossible to see in lateral view. Ambiguous for vertebrae where the dorsal and ventral margins of the canal are not parallel. 4. When two instances of the vertebra are optimally articulated, the same points are at the same height on both. This is less intuitive than definitions 1–3, but more precise and can be determined for any vertebra. We advocate explicitly stating a definition and using it consistently.

A reevaluation of Sigilmassasaurus brevicollis (Dinosauria) from the Cretaceous of Morocco

2013 ◽  
Vol 50 (6) ◽  
pp. 636-649 ◽  
Author(s):  
Bradley McFeeters ◽  
Michael J. Ryan ◽  
Sanja Hinic-Frlog ◽  
Claudia Schröder-Adams
Keyword(s):  
Phylogenetic Analysis ◽  
Diagnostic Character ◽  
Neural Spine ◽  
Dorsal Margin ◽  
Neural Arch ◽  
Anterior Dorsal ◽  
Neural Canal ◽  
Valid Taxon

The original hypodigm of the controversial mid-Cretaceous Moroccan dinosaur Sigilmassasaurus brevicollis is redescribed, and the diagnosis of the taxon is revised. Unambiguously referred material is restricted to cervical and anterior dorsal vertebrae sharing apomorphies with the holotype. A newly recognized diagnostic character of Sigilmassasaurus is the absence of anterior and posterior interzygapophyseal laminae of the neural arch, so that the neural spine directly meets the dorsal margin of the neural canal. A phylogenetic analysis supports the inclusion of Sigilmassasaurus in Tetanurae but not in Carcharodontosauridae. Sigilmassasaurus is distinct from all other theropods known from comparable material and is thus retained as a valid taxon.

Do Writing Directions Influence How People Map Space onto Time?

2018 ◽  
Vol 77 (4) ◽  
pp. 173-184
Author(s):  
Wenxing Yang ◽  
Ying Sun
Keyword(s):  
Mental Representations ◽  
Space Time ◽  
Horizontal Axis ◽  
Causal Role ◽  
Writing Systems ◽  
Temporal Cognition ◽  
Japanese Speakers ◽  
Psychological Experiments ◽  
Vertical Up

Abstract. The causal role of a unidirectional orthography in shaping speakers’ mental representations of time seems to be well established by many psychological experiments. However, the question of whether bidirectional writing systems in some languages can also produce such an impact on temporal cognition remains unresolved. To address this issue, the present study focused on Japanese and Taiwanese, both of which have a similar mix of texts written horizontally from left to right (HLR) and vertically from top to bottom (VTB). Two experiments were performed which recruited Japanese and Taiwanese speakers as participants. Experiment 1 used an explicit temporal arrangement design, and Experiment 2 measured implicit space-time associations in participants along the horizontal (left/right) and the vertical (up/down) axis. Converging evidence gathered from the two experiments demonstrate that neither Japanese speakers nor Taiwanese speakers aligned their vertical representations of time with the VTB writing orientation. Along the horizontal axis, only Japanese speakers encoded elapsing time into a left-to-right linear layout, which was commensurate with the HLR writing direction. Therefore, two distinct writing orientations of a language could not bring about two coexisting mental time lines. Possible theoretical implications underlying the findings are discussed.

Dependence of the joint configuration on the dynamic immobility fulcrum

2019 ◽  
pp. 108-114
Author(s):  
A. D. Kozlov ◽  
Yu. P. Potekhina
Keyword(s):  
Kinetic Energy ◽  
Convex Surface ◽  
The Other ◽  
Concave Surface ◽  
Joint Configuration ◽  
Articular Surfaces

Although joints with synovial cavities and articular surfaces are very variable, they all have one common peculiarity. In most cases, one of the articular surfaces is concave, whereas the other one is convex. During the formation of a joint, the epiphysis, which has less kinetic energy during the movements in the joint, forms a convex surface, whereas large kinetic energy forms the epiphysis with a concave surface. Basing on this concept, the analysis of the structure of the joints, allows to determine forces involved into their formation, and to identify the general patterns of the formation of the skeleton.

The description of a new Bruchophagus species (Hymenoptera, Chalcidoidea, Eurytomidae) developing in seeds of Melilotus officinalis (L.) Descr. (Fabaceae) in Iran

2019 ◽  
Vol 16 (1) ◽  
pp. 12-15
Author(s):  
M.D. Zerova ◽  
A. Al-Sendi ◽  
V.N. Fursov ◽  
H. Adeli-Manesh ◽  
S.E. Sadeghi ◽  
...  
Keyword(s):  
New Species ◽  
Host Plant ◽  
Lotus Corniculatus ◽  
Lateral View ◽  
National Academy Of Sciences ◽  
Melilotus Officinalis ◽  
Biological Features ◽  
Academy Of Sciences

The new species, Bruchophagus ayadi sp.n., is reared from seed pods of Melilotus officinalis (L.) Desr. (Fabaceae) in Iran (Lorestan). The new species is close to B. platypterus (Walk.), but differs by roundish abdomen and very gibbous, almost globular (in lateral view) mesosoma. These species can be also differentiated by some biological features. The host plant of B. platypterus is Lotus corniculatus L., whereas the new species is reared from Melilotus officinalis (L.) Desr. Holotype of Bruchophagus ayadi sp.n. is deposited in the collection of I.I. Schmalhausen Institute of Zoology of National Academy of Sciences of Ukraine (Kyiv).

Withdrawal: Computations of Aerodynamic Behaviour of Small Horizontal Axis Wind Turbine with NACA4418 airfoil

2019 ◽  
Author(s):  
Essam E. Khalil ◽  
Gamal E. ElHarriri ◽  
Eslam E. AbdelGhany ◽  
Moemen E. Farghaly
Keyword(s):  
Wind Turbine ◽  
Horizontal Axis ◽  
Horizontal Axis Wind Turbine
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