scholarly journals Complete Inversion of Epiglottis During Swallowing

2020 ◽  
Author(s):  
Keyword(s):  
Complete Inversion

Induced segmental reorganization in sabellid worms

Development ◽  
1978 ◽  
Vol 47 (1) ◽  
pp. 85-96
Author(s):  
N. J Berrill
Keyword(s):  
Unique Feature ◽  
Vertical Plane ◽  
Main Axis ◽  
The Other ◽  
Basal Portion ◽  
Thoracic Stomach ◽  
The Right ◽  
Number Of Segments ◽  
Head Regeneration ◽  
Complete Inversion

Processes of regeneration and reorganization are analyzed in two sabellid polychaetes. Abdominal pieces of Branchiomma nigromaculata, during head regeneration, ordinarily reorganize only a fraction of the number of segments typical of the thorax. In pieces transected in the vertical plane, but obliquely with regard to the main axis of the worm, the extent of reorganization is greatly enhanced. The same number of segments transform on the right and left sides, the surviving damaged segments transforming on one side and a corresponding number of more posterior, undamaged segments transforming on the other. Reorganization is shown, in abdominal pieces of Sabella melanostigma, to involve destruction and inversed dorso-ventral reconstitution of all parapodial structures in the segments affected, the conversion of intestine to thoracic stomach, and the invasion of previously abdominal segments by a pair of large nephridia which grow posteriorly after being formed in the basal portion of the head blastema. All three events exhibit a time-graded character, starting soonest at the anterior end and progressively later posteriorly, and apparently independently of one another. Abdominal type segments are formed only from the anterior region of the caudal, prepygidial zone of growth, successively, never by transformation. The dorso-ventrality of abdominal segments is the inverse of the thoracic, with the antero-posterior polarity unchanged, in all circumstances. Only during posterior regeneration from thoracic segments are thoracic segments produced from the posterior zone of growth, but only two or three are thus formed, the zone of growth then changing to the production of abdominal segments. It is concluded that the unique feature of sabellid-serpulid organization is the complete inversion of the dorso-ventrality of the posterior zone of growth as the result of emancipation from the generally dominating dorsal field emanating from the anterior end.

A Foldamer-Based Chiroptical Molecular Switch That Displays Complete Inversion of the Helical Sense upon Anion Binding

2011 ◽  
Vol 133 (35) ◽  
pp. 13938-13941 ◽  
Author(s):  
Jae-min Suk ◽  
Veluru Ramesh Naidu ◽  
Xinfang Liu ◽  
Myoung Soo Lah ◽  
Kyu-Sung Jeong
Keyword(s):  
Molecular Switch ◽  
Anion Binding ◽  
Complete Inversion

The effects of very deep ploughing and of subsoiling on crop yields

1956 ◽  
Vol 48 (2) ◽  
pp. 129-144 ◽  
Author(s):  
E. W. Russell
Keyword(s):  
Sugar Beet ◽  
Surface Soil ◽  
Crop Yields ◽  
Clay Soils ◽  
Deep Tillage ◽  
Perennial Weeds ◽  
The Difference ◽  
Annual Weeds ◽  
Dry Out ◽  
Complete Inversion

1. Deep tillage, namely, ploughing to a depth exceeding 12 in., or subsoiling to a depth of about 18 in., increased crop yields on about half the fields in which an experiment was made. Unfortunately, it was not possible to recognize what was the difference in soil properties between the 50% of fields that responded appreciably to deep tillage and the remainder whose yields were either unaffected or sometimes reduced by deep tillage, though, as one would expect, sands were normally less responsive to deep tillage than the heavier soils.2. On the clay soils, deep ploughing in autumn tended to give a surface soil that dried out up to several weeks earlier in the spring than land that was shallow ploughed. Subsoiling did not cause the surface soil to dry out in the same way. Only rarely did the subsoil brought up by deep ploughing give difficulty in working down to a seedbed, and probably in as high a proportion of fields the subsoil worked easier than the surface soil.3. On the clays and loams, the response of potatoes to deep tillage was more marked on fields that were heavily manured than on those lightly manured.4. Sugar beet normally gave a higher yield if its potash and phosphate was spread on the land before ploughing, even if this was in the autumn, than if it was applied in the seedbed. The exceptions to this result were for soils heavier than sandy loams if ploughing depths exceeding 12 in. were used, for the yield of beet was, on the average, depressed on these soils if the potash and phosphate was ploughed in compared with it being worked into the seedbed.5. Deep ploughing tended to give better control of many perennial weeds, and often of annual weeds than shallow ploughing. It is suggested that much of this benefit could be obtained when ploughing to 9–10 in. deep if ploughs were used that cut a furrow considerably wider than the conventional 10½–11 in. furrow, so allowing more complete inversion of the furrow slice.

Forerunners of the Romans

Antiquity ◽  
1928 ◽  
Vol 2 (5) ◽  
pp. 26-36 ◽  
Author(s):  
D. Randall-MacIver
Keyword(s):  
Second Century ◽  
Local Culture ◽  
Bare Life ◽  
The Real ◽  
Arts And Humanities ◽  
The Arts ◽  
The World ◽  
The Future ◽  
The Republic ◽  
Complete Inversion

The standard Roman histories, especially when written by authors who have an undisguised contempt for archaeology, give very little idea of the civilization and development of Italy before the later days of the Republic. They are histories of Rome but not of Italy. And so the reader is subconsciously led to suppose that the Romans were the most important and the most advanced people on the peninsula, who gradually extended the benefits of their superior civilization over a series of more or less barbarous neighbours. This is a complete inversion of the real facts. The Romans of the Republic were a rather backward people, and it was hardly before the second century B.C. that they could begin to rank as the equals of the Italian provincials in general refinement and culture. Incessantly occupied with the wars which were essential to their very existence, the Romans had no leisure, even if they possessed the inclination, to cultivate the arts and humanities. But, while the future head of the world was struggling for bare life, a rich Italian civilization had been born and developed in the independent territories which had not yet fallen under her sway. Before ever they came under the organizing and levelling domination of the central capital, Etruria, Venetia, Lombardy and Picenum had each evolved its own distinct and very valuable local culture; while the whole south from Naples to Brindisi had been civilized by Corinthian and Ionic influence. Rome when she conquered and annexed these territories in due sequence fell heir to a fully finished product. Italy had been created, but not by Rome; the task that fell to the Romans was much more suited to their peculiar abilities—they had to organize and administer the country.

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