scholarly journals STRAY NOTES ON MYRMELEONIDÆ, Part 4

1888 ◽  
Vol 20 (4) ◽  
pp. 72-74
Author(s):  
H. A. Hagen
Keyword(s):  
Posterior Half ◽  
Fine Line ◽  
Longitudinal Band ◽  
Anterior Half ◽  
Black Band

6. Brachynemurus nigrilabris Hagen. N. sp.Very similar to B. peregrinus. Face yellow, above with a large black band, which is rounded below and reaches nearly the clypeus; this band is going between and around the antennæ and connected above with the black part covering the whole anterior half of the vertex; posterior half yellow with a broad black longitudinal band, dilated angularly in middle; the angle sometimes protracted on each side in fine line, which does not reach the eyes; labrum shining black; palpi yellow, last joint of the maillary cylindrical black; labials a little longer, last joint shining black, fusiform, sharply pointed, less inflated than in B. peregrinus.

Retinoic acid induces a pattern of digits in anterior half wing buds that lack the zone of polarizing activity

Development ◽  
1989 ◽  
Vol 107 (4) ◽  
pp. 863-867 ◽  
Author(s):  
G. Eichele
Keyword(s):  
Retinoic Acid ◽  
Cell Fate ◽  
Anterior Margin ◽  
Limb Bud ◽  
Posterior Half ◽  
Anterior Half ◽  
Zone Of Polarizing Activity

Wing buds whose posterior half is excised, develop into wings lacking distal structures. However, such experimentally generated preaxial half wing buds can be rescued by implanting a retinoic-acid-releasing bead at their anterior margin. The polarity of the pattern that originates from preaxial half wing buds is reversed. For example, instead of a 234 digit pattern typical for normal wings, the order of digits is 432. This result implies that retinoic acid has the capacity to reprogram anterior limb bud tissue, and that the resulting change in cell fate does not depend on the presence of posterior tissue regions such as the zone of polarizing activity (ZPA).

The development of hepatogenic potency in the endoderm of quail embryos

Development ◽  
1979 ◽  
Vol 52 (1) ◽  
pp. 49-62
Author(s):  
Sumiko Fukuda
Keyword(s):  
Digestive Tract ◽  
The Other ◽  
Chick Embryos ◽  
Posterior Half ◽  
Coelomic Cavity ◽  
Somite Stage ◽  
Anterior Half ◽  
Other Hand ◽  
Cardiac Region ◽  
Cardiac Mesenchyme

Hepatogenic potency of the endoderm is detectable in the anterior half of the endoderm of quail embryos older than 2-somite stage when endodermal fragments are cultured with or without heterologous chick mesenchymes, in the coelomic cavity of 3-day chick embryos. On the other hand, the posterior half of the endoderm never has hepatogenic potency. The hepatogenic potency of the endoderm is gradually stabilised with increasing age. However, expression of hepatogenesis can be affected when the endoderm is associated with inductively active digestive tract mesenchymes. Mesenchyme taken from the presumptive cardiac region (‘cardiac’ mesenchyme) of chick embryos is necessary for the uncommitted anterior endoderm to acquire hepatogenic potency, and this effect is specific for the ‘cardiac’ mesenchyme. The ‘cardiac’ mesenchyme, however, fails to induce hepatic epithelium in the allantoic endoderm, which can differentiate heterotypically when cultured in combination with digestive tract mesenchymes. The evidence presented in this study suggests that the effect of ‘cardiac’ mesenchyme on the acquisition of hepatogenic potency in the endoderm is limited.

Gross anatomical features of the sternum of green-winged macaw (Ara Chloroptera)

2015 ◽  
Vol 49 (6) ◽  
Author(s):  
A. R. Sreeranjini ◽  
N. Ashok ◽  
V. R. Indu ◽  
K. M. Lucy ◽  
S. Maya ◽  
...  
Keyword(s):  
Anterior Extremity ◽  
Dorsal Surface ◽  
Ventral Surface ◽  
Morphological Features ◽  
Posterior Border ◽  
Posterior Half ◽  
Lateral Border ◽  
Convex Surfaces ◽  
Anatomical Features ◽  
Anterior Half

The present study was conducted on the sternum of an eight year old, male Green-winged Macaw. The sternum was quadrilateral with dorsal concave and ventral convex surfaces and four borders. The dorsal surface presented numerous pneumatic foramina. The ventral surface furnished a large, boat shaped keel. The anterior extremity showed two facets for coracoid. The anterior and posterior borders were convex. The lateral border on either side presented six costal facets. Two distinct oval foramina were seen near the posterior border. Craniolateral processes were short and stump-like. Caudolateral processes fused with the median trabecula on either side. The rostrum was distinct. The morphological features of the sternum of Green-winged Macaw conformed to that of flying group of birds. It was almost similar to that of goose in its anterior half and to that of pigeon in its posterior half.

Comparing Yin-Yang, the Chinese Symbol of Creation, with Ouroboros of Greek Alchemy

1989 ◽  
Vol 17 (03n04) ◽  
pp. 95-98 ◽  
Author(s):  
S. Mahdihassan
Keyword(s):  
Posterior Half ◽  
Anterior Portion ◽  
Male And Female ◽  
Anterior Half ◽  
Yin Yang ◽  
The Universe ◽  
The Ideal

The universe was early divided into Earth below and Heaven above. These, two as one, gave the idea of opposites but forming a unity. Each opposite was assumed to be powerful and so was their final unity. For creation of the universe they projected reproduction to conceive creation. Now reproduction results in the union of two opposites as male and female. Correspondingly, the Chinese believed Light and Darkness, as the ideal opposites, when united, yielded creative energy. The two opposites were further conceived as matter and energy which became dual-natured but as one. The two opposites were yin-yang and their unity was called Chhi, Yin-Yang was treated separately in Chinese cosmology which consisted of five cosmic elements. Since Chinese alchemy did reach Alexandria probably the symbol Yin-Yang, as dual-natured, responsible for creation, was transformed into a symbol called Ouroboros, It is a snake and as such a symbol of soul. Its head and anterior portion is red, being the colour of blood as soul; its tail and posterior half is dark, representing body. Ouroboros here is depicted white and black, as soul and body, the two as "one which is all". It is cosmic soul, the source of all creation. Ouroboros is normally depicted with its anterior half as black but it should be the reverse as shown here. With the name Chemeia taken to Kim-Iya, the last word would take Ouroboros to Yin-Yang.

scholarly journals On the ‘blaze-currents’ of the crystalline lens

1903 ◽  
Vol 71 (467-476) ◽  
pp. 194-211
Keyword(s):  
Crystalline Lens ◽  
Electrical Excitation ◽  
Posterior Half ◽  
Anterior Half ◽  
Effective Part

In the course of investigation of the effects of light and of electrical excitation on the frog’s eyeball, I came to the conclusion that tissues other than retinal are coeffective in the response to strong induction hocks, and proceeded therefore to look for blaze-currents in other iving tissues. The particular point that aroused my attention in the case of the eyeball was the fact that the anterior half of the eyeball was some-times found to give a larger response than the posterior half, and the present observations proceed from an attempt to determine the principally effective part in such reaction. And I may state at once, as my chief conclusion, that it is the crystalline lens.

An Endoscopic Method of Tympanic Membrane Fluorescein Angiography

1986 ◽  
Vol 95 (5) ◽  
pp. 439-443 ◽  
Author(s):  
Edward L. Applebaum ◽  
Elise C. Deutsch
Keyword(s):  
Fluorescein Angiography ◽  
Tympanic Membrane ◽  
Arterial Phase ◽  
Posterior Half ◽  
Temporalis Fascia ◽  
Fundus Camera ◽  
Anterior Half ◽  
Endoscopic Method ◽  
Xenon Light Source ◽  
Xenon Light

Fluorescein angiography is a recently developed method of studying the tympanic membrane's dynamic vasculature. Our preliminary studies using an ophthalmic fundus camera and aural speculum did not always permit visualization of the entire tympanic membrane, and the electronic flash unit used in our initial studies did not cycle fast enough to visualize effectively the rapid arterial phase of blood flow. In this report, we describe an endoscopic method of tympanic membrane fluorescein angiography that uses a continuous xenon light source. A representative angiogram from a normal subject is described. The mallear artery apparently is the major blood supply to the posterior half of the tympanic membrane, which is consistently better perfused than the anterior half. Branches from the annular ring of blood vessels supply the anterior half of the tympanic membrane. Preliminary studies of two temporalis fascia tympanoplasty patients indicate that the graft becomes revascularized 2 to 4 weeks after surgery and that posterior grafts may revascularize earlier than anterior grafts.

Microvascular anatomy of the interpeduncular fossa

1986 ◽  
Vol 64 (3) ◽  
pp. 484-493 ◽  
Author(s):  
Alfredo Pedroza ◽  
Manuel Dujovny ◽  
James I. Ausman ◽  
Fernando G. Diaz ◽  
Jose Cabezudo Artero ◽  
...  
Keyword(s):  
Basilar Artery ◽  
Polyester Resin ◽  
Posterior Cerebral Artery ◽  
Posterior Half ◽  
Small Space ◽  
Content Type ◽  
Brain Hemispheres ◽  
Naturally Occurring ◽  
Anterior Half ◽  
Fine Print

✓ An understanding of the microvascular anatomy of the midbrain and posterior diencephalon is essential in the surgical management of lesions in that region. A description of the arterial pattern of blood supply to these areas is the purpose of this study. Perforating branches originating from the last 5 mm of the basilar artery, from the initial 7 mm of both superior cerebellar arteries (SCA's), and from the initial segment (P1 segment) of the posterior cerebral artery were studied in 56 unfixed human cadaver brain hemispheres. The brains were injected with polyester resin. The perforating branches penetrated through a small space in the upper part of the interpeduncular fossa. The anterior two-thirds of this space was occupied by the posterior perforated substance (PPS), and the posterior one-third was the site of penetration of the branches that supply the inferior mesencephalon. The PPS was divided into anterior and posterior halves. The anterior half was perforated by the paramedian thalamic arteries (diameter 0.57 ± 0.11 mm) while the superior paramedian mesencephalic arteries (diameter 0.20 ± 0.06 mm) perforated the posterior half. The perforating arteries originated from a trunk exclusive to the anterior half in 30%, from a trunk supplying both halves in 57%, and from a trunk exclusive to the posterior half in 13% of specimens. There were 26 naturally occurring anastomoses between the perforating branches. The paramedian inferior mesencephalic arteries penetrating the posterior one-third of the upper part of the interpeduncular fossa arose from the P1 segment in 32% of the brains studied, from the proximal 7 mm of the SCA in 45%, and from the last 5 mm of the basilar artery in 23%.

Regeneration from half lower arms in the axolotl

Development ◽  
1986 ◽  
Vol 95 (1) ◽  
pp. 247-260
Author(s):  
Peter Wigmore
Keyword(s):  
Posterior Half ◽  
Upper Arm ◽  
Digit Number ◽  
Single Digit ◽  
Skeletal Structures ◽  
Anterior Dorsal ◽  
Anterior Half ◽  
Ventral Muscle ◽  
Posterior Anterior

A technique involving grafting of pieces of skin from the head onto the limb in order to isolate halves of the limb is described. This technique was used to isolate posterior, anterior, dorsal and ventral halves of the lower arm. All halves produced regenerates but no part of the limb was able to produce a high proportion of regenerates with a complete pattern of skeletal structures. Posterior half stumps regenerated limbs with a mean digit number of 2.7 and had a normal dorsoventral muscle pattern. Anterior half stumps produced a high proportion of single-digit regenerates and had a mean digit number of 1.3. Dorsal and ventral half stumps regenerated limbs with a mean digit number of 2.8 and 2.3 respectively. Hypomorphic regenerates from dorsal and ventral half stumps often had only dorsal or ventral muscle. These results are in contrast to those from the upper arm (Wigmore & Holder, 1985) where a complete skeletal and muscular pattern regenerated from posterior and dorsal halves and hypomorphic regenerates were obtained from anterior and ventral half limbs.

The Lesion in Stereotactic Subcaudate Tractotomy

1975 ◽  
Vol 126 (5) ◽  
pp. 478-481 ◽  
Author(s):  
R. L. G. Newcombe
Keyword(s):  
White Matter ◽  
Posterior Half ◽  
Anatomical Distribution ◽  
Central Segment ◽  
Anterior Half ◽  
Frontal White Matter

SummaryThe anatomical distribution of 25 stereotactic tractotomy lesions is described. The posterior half of these lesions lie in a subcaudate position and the anterior half, for the most part, lies beneath the central segment of frontal white matter.

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