scholarly journals From the herringbone dome by Sangallo to the Serlio floor of Emy (and beyond)

2021 ◽  
Vol 8 (1) ◽  
pp. 259-270
Author(s):  
Giulio Mirabella Roberti ◽  
Giuseppe Ruscica ◽  
Vittorio Paris
Keyword(s):  
Thin Shells ◽  
Spiral Pattern ◽  
Structural Scheme ◽  
Wooden Floor ◽  
Construction Stage ◽  
Structural Role ◽  
Double Spiral ◽  
The Cross ◽  
Structural Solutions ◽  
Geometrical Relationship

Abstract The research starts from an analogy found between two apparently very different structural solutions: the double spiral pattern of the herringbone brick courses in the domes built by Antonio da Sangallo the Younger (1484-1546) during the Renaissance, and the particular pattern of a wooden floor ‘à la Serlio’, described by Amand Rose Emy in his Treatise at the beginning of 19th century, made by diagonal beams reciprocally sustained. The diagonal pattern of the floor has a geometrical relationship with the cross-herringbone pattern, so that the latter can be obtained by some geometrical transformations of the former. This pattern was also used in thin shells built by Nervi, from the destroyed airplane hangars in Tuscany to the Palazzetto dello sport in Rome, and even by Piacentini in 1936 and earlier in some neoclassical domes. Thus the construction tool, useful for building domes without expensive scaffolding, could have a structural role at the completed construction stage. Within the research different structures were investigated, in order to observe the relevance of this peculiar structural scheme particularly in the construction of modern domes.

Microtubule-organizing centres and assembly of the double-spiral microtubule pattern in certain heliozoan axonemes

1981 ◽  
Vol 50 (1) ◽  
pp. 259-280
Author(s):  
J.C. Jones ◽  
J.B. Tucker
Keyword(s):  
Nuclear Envelope ◽  
Surface Membrane ◽  
Cold Treatment ◽  
Dense Material ◽  
Microtubule Assembly ◽  
Central Nucleus ◽  
Spiral Pattern ◽  
Microtubule Organizing Centres ◽  
Double Spiral ◽  
Actinophrys Sol

The double-spiral microtubule pattern is established by a self-linkage procedure when axopodial axonemes reassemble after cold treatment in multinucleate Echinosphaerium nucleofilum and mononucleate Actinophrys sol. Nuclei are related spatially to axoneme morphogenesis in both organisms but in rather different ways. Microtubules grow out in all directions from discrete clumps of dense material situated close to nuclei in E. nucleofilum as axonemal assembly begins. Each clump acts as a microtubule-organizing centre (MTOC) in so far as it is associated spatially with the assembly of microtubules for a single axoneme. The dense material spreads along the sides of a developing axoneme for several micrometers, where it probably promotes further microtubule assembly as the double-spiral pattern is established. Pattern is generated as microtubules that are randomly oriented to begin with become more closely juxtaposed and aligned with each other. There are indications that juxtaposition is brought about by the contractile action of a filamentous meshwork that interconnects the microtubules. Final positioning and alignment appears to be accomplished by a ‘zippering’ together of adjacent portions of microtubules that proceeds in both directions along the lengths of developing axonemes as self-linkage is effected. Considerable numbers of more or less radially oriented microtubules remain and project from the surface membrane of the single central nucleus during cold treatment of A. sol. Additional tubules assemble and become associated similarly with the nuclear envelope immediately after cold treatment. Initially these microtubules are not arranged in a double-spiral pattern, which is subsequently generated by procedures similar to those outlined above for E. nucleofilum. It is suggested that the surface of the nuclear envelope may act as an MTOC.

scholarly journals RESEARCH OF THE FOUNDATION CONSOLIDATED BY DIFFERENT-SIZED HORIZONTAL ELEMENTS

Vestnik MGSU ◽  
2016 ◽  
pp. 39-51
Author(s):  
Elena Aleksandrovna Isakova ◽  
Tat’yana Mikhaylovna Bochkareva
Keyword(s):  
Soil Mass ◽  
Model Tests ◽  
Soil Base ◽  
Soil Pressure ◽  
Weak Soil ◽  
Structural Scheme ◽  
Severe Accidents ◽  
Soil Settlement ◽  
Structural Solutions ◽  
Structural Solution

The article is dedicated to the problem of geotechnics. The problems of the weak soil base are topical. Also there sometimes happen severe accidents of soil mass. A great number of such emergencies is of a progressive character, when a local crash leads to the crash of the whole construction. Tarring the soil with epoxy can ensure geotechnical safety of the basis. That’s why the improvement of this method is needed in order to reduce yielding of the base, create ground water cutoff or create building hoisting. In the article new structural solutions for reduction of settlement are presented. The authors suggest using the manufactured plane elements containing epoxy. Such elements have different sizes and lie underneath the foundation. Similar structural scheme can be used to reduce soil settlement. The authors carried out two series of plate-bearing model tests with manufactured plane epoxy elements. In the first series of tests the biggest element was closer to the foundation, the smallest element was closer to the biggest element. In the second series of tests the smallest element was closer to the foundation, the biggest element was closer to the smallest element. After the end of plate-bearing model tests the authors received values of the base settlement and the dependency diagrams “base settlement-soil pressure”. The new structural solution for reducing soil settlement proved to be effective. Settlement of base decreased sevenfold.

Density waves in disk galaxies

1967 ◽  
Vol 31 ◽  
pp. 313-317 ◽  
Author(s):  
C. C. Lin ◽  
F. H. Shu
Keyword(s):  
Mathematical Analysis ◽  
Spiral Structure ◽  
Stellar System ◽  
Collective Modes ◽  
Disk Galaxies ◽  
Spiral Pattern ◽  
Density Waves ◽  
The Galaxy ◽  
Detailed Mathematical Analysis

Density waves in the nature of those proposed by B. Lindblad are described by detailed mathematical analysis of collective modes in a disk-like stellar system. The treatment is centered around a hypothesis of quasi-stationary spiral structure. We examine (a) the mechanism for the maintenance of this spiral pattern, and (b) its consequences on the observable features of the galaxy.

A New Approach to the Demonstration of Oxidase-Localization Using Tannic Acid Or Catechin

1973 ◽  
Vol 31 ◽  
pp. 698-699
Author(s):  
V. Mizuhira ◽  
Y. Futaesaku
Keyword(s):  
Cross Section ◽  
Tannic Acid ◽  
Elastic Fiber ◽  
The Other ◽  
New Approach ◽  
Tissue Block ◽  
Active Reaction ◽  
The Cross

Previously we reported that tannic acid is a very effective fixative for proteins including polypeptides. Especially, in the cross section of microtubules, thirteen submits in A-tubule and eleven in B-tubule could be observed very clearly. An elastic fiber could be demonstrated very clearly, as an electron opaque, homogeneous fiber. However, tannic acid did not penetrate into the deep portion of the tissue-block. So we tried Catechin. This shows almost the same chemical natures as that of proteins, as tannic acid. Moreover, we thought that catechin should have two active-reaction sites, one is phenol,and the other is catechole. Catechole site should react with osmium, to make Os- black. Phenol-site should react with peroxidase existing perhydroxide.

Structures Resembling Striated Rootlets in Oocytes

1972 ◽  
Vol 30 ◽  
pp. 124-125
Author(s):  
Valerie V. Ernst
Keyword(s):  
Golgi Complex ◽  
Fibrous Structure ◽  
Oocyte Development ◽  
The Cross

During the earliest stage of oocyte development in the limpet, Acmea scutum, Golgi complexes are small, few and randomly dispersed in the cytoplasm. As growth proceeds, the Golgi complexes increase in size and number and migrate to the periphery of the cell. At this time, fibrous structures resembling striated rootlets occur associated with the Golgi complexes. Only one fibrous structure appears to be associated with a Golgi complex.The fibers are periodically cross banded with an average of 4 dense fibrils and 6 lighter fibrils per period (Fig. 1). The cross fibrils have a center to center spacing of about 7 run which appears to be the same as that of the striated rootlets of the gill cilia in this animal.

Energy Distribution in Electron Beams

1972 ◽  
Vol 30 ◽  
pp. 568-569
Author(s):  
Tamotsu Ohno
Keyword(s):  
Electron Beam ◽  
Energy Distribution ◽  
Cross Section ◽  
Integral Curve ◽  
Electron Beams ◽  
Electron Gun ◽  
Angular Divergence ◽  
Apparent Increase ◽  
Integral Width ◽  
The Cross

The energy distribution in an electron; beam from an electron gun provided with a biased Wehnelt cylinder was measured by a retarding potential analyser. All the measurements were carried out with a beam of small angular divergence (<3xl0-4 rad) to eliminate the apparent increase of energy width as pointed out by Ichinokawa.The cross section of the beam from a gun with a tungsten hairpin cathode varies as shown in Fig.1a with the bias voltage Vg. The central part of the beam was analysed. An example of the integral curve as well as the energy spectrum is shown in Fig.2. The integral width of the spectrum ΔEi varies with Vg as shown in Fig.1b The width ΔEi is smaller than the Maxwellian width near the cut-off. As |Vg| is decreased, ΔEi increases beyond the Maxwellian width, reaches a maximum and then decreases. Note that the cross section of the beam enlarges with decreasing |Vg|.

On the cross-sectional shape of the cellulose crystallites in the tunicate Halocynthia papillosa

1990 ◽  
Vol 48 (3) ◽  
pp. 566-567
Author(s):  
J.-F. Revol ◽  
Y. Van Daele ◽  
F. Gaill
Keyword(s):  
Contrast Imaging ◽  
Animal Kingdom ◽  
Bright Field ◽  
Field Mode ◽  
Cross Sectional ◽  
Ultrathin Sections ◽  
The Cross ◽  
Sectional Shape ◽  
Valonia Ventricosa ◽  
C Nmr

The only form of cellulose which could unequivocally be ascribed to the animal kingdom is the tunicin that occurs in the tests of the tunicates. Recently, high-resolution solid-state l3C NMR revealed that tunicin belongs to the Iβ form of cellulose as opposed to the Iα form found in Valonia and bacterial celluloses. The high perfection of the tunicin crystallites led us to study its crosssectional shape and to compare it with the shape of those in Valonia ventricosa (V.v.), the goal being to relate the cross-section of cellulose crystallites with the two allomorphs Iα and Iβ.In the present work the source of tunicin was the test of the ascidian Halocvnthia papillosa (H.p.). Diffraction contrast imaging in the bright field mode was applied on ultrathin sections of the V.v. cell wall and H.p. test with cellulose crystallites perpendicular to the plane of the sections. The electron microscope, a Philips 400T, was operated at 120 kV in a low intensity beam condition.

A Longitudinal Study of Mental Health in Emerging Adults

2014 ◽  
Vol 73 (3) ◽  
pp. 135-141 ◽  
Author(s):  
Monica S. Bachmann ◽  
Hansjörg Znoj ◽  
Katja Haemmerli
Keyword(s):  
Mental Health ◽  
Longitudinal Study ◽  
Emerging Adults ◽  
Poor Mental Health ◽  
Need Satisfaction ◽  
Computer Assisted ◽  
Consistency Model ◽  
Negative Effect ◽  
The Cross ◽  
Health Model

Emerging adulthood is a time of instability. This longitudinal study investigated the relationship between mental health and need satisfaction among emerging adults over a period of five years and focused on gender-specific differences. Two possible causal models were examined: (1) the mental health model, which predicts that incongruence is due to the presence of impaired mental health at an earlier point in time; (2) the consistency model, which predicts that impaired mental health is due to a higher level of incongruence reported at an earlier point in time. Emerging adults (N = 1,017) aged 18–24 completed computer-assisted telephone interviews in 2003 (T1), 2005 (T2), and 2008 (T3). The results indicate that better mental health at T1 predicts a lower level of incongruence two years later (T2), when prior level of incongruence is controlled for. The same cross-lagged effect is shown for T3. However, the cross-lagged paths from incongruence to mental health are marginally associated when prior mental health is controlled for. No gender differences were found in the cross-lagged model. The results support the mental health model and show that incongruence does not have a long-lasting negative effect on mental health. The results highlight the importance of identifying emerging adults with poor mental health early to provide support regarding need satisfaction.

The Cross-Cultural Equivalence of Parental Rearing Measure: EMBU-C

2006 ◽  
Vol 22 (2) ◽  
pp. 85-91 ◽  
Author(s):  
Maja Deković ◽  
Margreet ten Have ◽  
Wilma A.M. Vollebergh ◽  
Trees Pels ◽  
Annerieke Oosterwegel ◽  
...  
Keyword(s):  
Factor Analysis ◽  
Cultural Differences ◽  
Cross Cultural ◽  
Child Rearing ◽  
Latent Factors ◽  
Immigrant Adolescents ◽  
Confirmatory Factor ◽  
Parental Rearing ◽  
The Cross ◽  
Multigroup Confirmatory Factor Analysis

We examined the cross-cultural equivalence of a widely used instrument that assesses perceived parental rearing, the EMBU-C, among native Dutch and immigrant adolescents living in The Netherlands. The results of a multigroup confirmatory factor analysis indicated that the factor structure of the EMBU-C, consisting of three latent factors (Warmth, Rejection, and Overprotection), and reliabilities of these scales are similar in both samples. These findings lend further support for the factorial and construct validity of this instrument. The comparison of perceived child rearing between native Dutch and immigrant adolescents showed cultural differences in only one of the assessed dimensions: Immigrant adolescents perceive their parents as more overprotective than do Dutch adolescents.

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