scholarly journals Agustín de Betancourt’s Double-Acting Steam Engine: Geometric Modeling and Virtual Reconstruction

Symmetry ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 351 ◽  
Author(s):  
José Rojas-Sola ◽  
Belén Galán-Moral ◽  
Eduardo De la Morena-De la Fuente
Keyword(s):  
Computer Aided Design ◽  
Geometric Modeling ◽  
Degrees Of Freedom ◽  
Mechanical Energy ◽  
Steam Engine ◽  
3D Cad ◽  
Virtual Reconstruction ◽  
History Of ◽  
The Right ◽  
Almost All

In this paper, the geometric modeling and virtual reconstruction of the double-acting steam engine designed by Agustín de Betancourt in 1789 are shown. For this, the software Autodesk Inventor Professional is used, which has allowed us to obtain its geometric documentation. The material for the research is available on the website of the Betancourt Project of the Canary Orotava Foundation for the History of Science. Almost all parts of the steam engine are drawn on the sheets, but due to the absence of scale and space, it is insufficient to obtain an accurate and reliable 3D CAD (Computer-Aided Design) model. For this reason a graphic scale has been adopted so that the dimensions of the elements are coherent. Also, it has been necessary to make some dimensional and geometric hypotheses, as well as restrictions of movement (degrees of freedom). Geometric modeling has made it possible to know that the system is balanced with the geometric center of the rocker arm shaft, and presents an energetic symmetry whose axis is the support of the parallelogram where the shaft rests: calorific energy to the left and mechanical energy to the right, with the rocker arm acting as a transforming element from one to the other.

scholarly journals The Hay Inclined Plane in Coalbrookdale (Shropshire, England): Geometric Modeling and Virtual Reconstruction

Symmetry ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 589 ◽  
Author(s):  
José Ignacio Rojas-Sola ◽  
Eduardo De la Morena-De la Fuente
Keyword(s):  
Geometric Modeling ◽  
Degrees Of Freedom ◽  
Working Capacity ◽  
Inclined Plane ◽  
3D Cad ◽  
Energy Needs ◽  
Virtual Reconstruction ◽  
History Of ◽  
Single Sheet ◽  
Different Levels

This article shows the geometric modeling and virtual reconstruction of the inclined plane of Coalbrookdale (Shropshire, England) that was in operation from 1792 to 1894. This historical invention, work of the Englishman William Reynolds, allowed the transportation of boats through channels located at different levels. Autodesk Inventor Professional software has been used to obtain the 3D CAD model of this historical invention and its geometric documentation. The material for the research is available on the website of the Betancourt Project of the Canary Orotava Foundation for the History of Science. Also, because the single sheet does not have a scale, it has been necessary to adopt a graphic scale so that the dimensions of the different elements are coherent. Furthermore, it has been necessary to establish some dimensional, geometric, and movement restrictions (degrees of freedom) so that the set will work properly. One of the main conclusions is that William Reynolds designed a mechanism seeking a longitudinal symmetry so that, from a single continuous movement, the mechanism allows two vessels to ascend and descend simultaneously. This engineering solution facilitated a doubling of the working capacity of the device, as well as a reduction of the energy needs of the system.

scholarly journals Agustín de Betancourt’s Optical Telegraph: Geometric Modeling and Virtual Reconstruction

2020 ◽  
Vol 10 (5) ◽  
pp. 1857 ◽  
Author(s):  
José Ignacio Rojas-Sola ◽  
Eduardo De la Morena-De la Fuente
Keyword(s):  
3D Modeling ◽  
Geometric Modeling ◽  
3D Model ◽  
18Th Century ◽  
Three Dimensional ◽  
Assembly System ◽  
Three Dimensional Modeling ◽  
Dimensional Modeling ◽  
Virtual Reconstruction ◽  
History Of

This article shows the geometric modeling and virtual reconstruction of the optical telegraph by Agustín de Betancourt and Abraham Louis Breguet developed at the end of the 18th century. Autodesk Inventor Professional software has been used to obtain the three-dimensional (3D) model of this historical invention and its geometric documentation. The material for the research is available on the website of the Betancourt Project of the Canary Orotava Foundation for the History of Science. Thanks to the three-dimensional modeling performed, it has been possible to explain in detail both its operation and the assembly system of this invention in a coherent way. After carrying out its 3D modeling and functional analysis, it was discovered that the transmissions in the telegraph were not performed by hemp ropes but rather by metal chains with flat links, considerably reducing possible error. Similarly, it has also been found that the use of the gimbal joint facilitated the adaptability of the invention to geographical areas where there was a physical impediment to the alignment of telegraph stations. In addition, it was not now necessary for the telescope frames to be located parallel to the mast frame (frame of the indicator arrow) and therefore they could work in different planes.

scholarly journals The earliest Fellows of the Royal Society

1950 ◽  
Vol 7 (2) ◽  
pp. 172-192 ◽  
Keyword(s):  
Royal Society ◽  
History Of ◽  
The Right ◽  
Almost All ◽  
First Time

The Royal Society was granted its first charter of incorporation on 15 July 1662, its second on 22 April 1663. Both charters name the President and the members of the Council of the Society; the second empowers the President and Council within the two months immediately succeeding the grant to admit into the Society as Fellows such persons as they (or a specified majority of them) shall think fit; after the two months have elapsed the right of admitting new Fellows is to belong to the President, Council, and existing Fellows. In accordance with this grant ninety-four Fellows were admitted on 20 May 1663 and four more on 22 June 1663 ; these ninety-eight are known as ‘Original Fellows‘. The Council consisted of twenty members apart from the President. The Society had originated in a group of scientists who first met about 1645. This group held informal meetings and apparently kept no records. On 28 November 1660 its members (or some of them) determined to hold their meetings more regularly and to form themselves into an association for doing so. The association, which for convenience may be called the Philosophical Society, drew up rules, provided for funds, and kept records. The last, so far as they are adequate, show who were admitted as members and when they were admitted. The President, the members of the first and second Councils, and the Original Fellows of the Royal Society, had almost all been members of the Philosophical Society; the dates when they became members of the Philosophical Society are therefore of greater interest, both for the history of the Society and for their individual biographies, than the dates of their appearance as Fellows of the Royal Society. The first of the following lists gives these dates, which are here brought together for the first time. In the course of compilation a few names were found of members or apparent members of the earlier society who did not become Fellows of the later one until after 22 June 1663 ; these names have been brought together in a second list. A third list contains the names of those members of the Philosophical Society who never became Fellows of the Royal Society as constituted under the Second Charter.

Surgical management of cervical radiculopathy caused by redundant vertebral artery loop

2012 ◽  
Vol 17 (4) ◽  
pp. 337-341 ◽  
Author(s):  
Ziad A. Hage ◽  
Sepideh Amin-Hanjani ◽  
Dennis Wen ◽  
Fady T. Charbel
Keyword(s):  
Vertebral Artery ◽  
Nerve Root ◽  
Cervical Radiculopathy ◽  
Surgical Approaches ◽  
Anterolateral Approach ◽  
Transverse Foramen ◽  
History Of ◽  
The Right ◽  
Almost All ◽  
Vascular Decompression

In this article, the authors describe the case of a 27-year-old female presenting with a 2-year history of neck pain and radiculopathy attributable to compression of the right C-7 nerve root by tortuosity of the vertebral artery at the level of the C6–7 cervical foramina. An anterolateral approach to the transverse foramen was used to perform a vascular decompression to decompress the nerve root. The procedure was uneventful, and the patient woke up with almost all of her symptoms resolved. The authors also include a literature review of techniques performed in this setting, showing that multiple surgical approaches can be used and should be tailored to the patient symptoms and lesion characteristics.

scholarly journals The Ophryotrocha labronica group (Annelida: Dorvilleidae)— with the description of seven new species

Zootaxa ◽  
2019 ◽  
Vol 2713 (1) ◽  
pp. 1 ◽  
Author(s):  
HANNELORE PAXTON ◽  
BERTIL ÅKESSON
Keyword(s):  
Upper Cretaceous ◽  
Reproductive Traits ◽  
Informal Group ◽  
Diploid Complement ◽  
History Of ◽  
Males And Females ◽  
Morphological Differences ◽  
The Right ◽  
Almost All ◽  
P Type

This paper reviews the group of gonochoristic Ophryotrocha species, known as the “O. labronica group”. This informal group is chararacterised by its unique maxillary P- and K-forceps and dorsomedian rosette glands. All members of the group are primarily gonochoristic and almost all have the diploid complement of chromosomes of 2n = 6. External morphological differences within the group are very slight. In males and females of all species the P-type maxillae change at maturity to the K-type with the right forceps being bifid. A jaw fossil from the Upper Cretaceous, attributable to the O. labronica group, attests to the long history of the group. As herein defined, the group includes: O. labronica labronica, O. labronica pacifica, O. costlowi sp. nov., O. dimorphica, O. japonica sp. nov., O. macrovifera sp. nov., O. notoglandulata, O. permanae sp. nov., O. robusta sp. nov., O. rubra sp. nov., O. schubravyi, O. vellae sp. nov., O. olympica, nom. nud., O. prolifica, nom. nud., and O. sativa, nom. nud.. Seven species are formally described and diagnoses are provided for all remaining taxa in the taxonomic section. This is followed by an illustrated discussion of the morphology, reproductive traits, and relationships of the members of the informal group.

Metastatic Adrenal Cortical Carcinoma: Biochemical Changes Accompanying Clinical Regression During Therapy with o,p'-DDD

1971 ◽  
Vol 17 (12) ◽  
pp. 1191-1193 ◽  
Author(s):  
Lawrence Helson ◽  
Norma Wollner ◽  
M Lois Murphy ◽  
Morton K Schwartz
Keyword(s):  
Lung Metastases ◽  
Abdominal Mass ◽  
Signs And Symptoms ◽  
Bone Age ◽  
Acth Stimulation ◽  
History Of ◽  
Bilateral Lung ◽  
The Right ◽  
Almost All ◽  
Dexamethasone Suppression

Abstract A 7-year-old girl with a six-month history of increasing virilism, growth, and acne excreted supranormal amounts of urinary 17-ketosteroids (87.6 mg/24 h). ACTH stimulation and dexamethasone suppression studies indicated adrenal tumor. A large left adrenal carcinoma was removed. Metastases were not observed. Postoperatively, 24-h urinary ketosteroids remained supranormal (16 mg). Sudden fever, cough, and hemoptysis precipitated hospitalization 42 months later. Bilateral lung metastases, a mass in the right upper quadrant, virilism, advanced bone age, and supranormal 24-h urinary ketosteroids (166 mg) and hydroxysteroids (16 mg) were found. The patient received 240 g of o,p'-dichlorodiphenyl-dichloroethane (o,p'-DDD), whereupon the abdominal mass and lung lesions regressed and 24-h urinary ketosteroids and hydroxysteroids decreased. Since this treatment (which ended April, 1968) the patient has been maintained at home on 7.5 g o,p'-DDD/day and replacement therapy with 9-α-fluorohydrocortisone and cortisone acetate. Almost all signs and symptoms have disappeared and urinary steroids are normal.

Suffrage Rights

2017 ◽  
Author(s):  
Humberto Llavador
Keyword(s):  
Women's Suffrage ◽  
Ruling Elite ◽  
Institutional Reforms ◽  
Compulsory Voting ◽  
History Of ◽  
Right To Vote ◽  
The Right ◽  
Almost All ◽  
Women’S Suffrage

The historical evolution of the right to vote offers three observations. First, almost all groups have seen their voting rights challenged at some point in time, and almost all political movements have sought to exclude some other group from voting. Second, reforms towards suffrage extension are varied—from the direct introduction of universal (male) suffrage to a trickle down process of enfranchising a small group at a time. Third, the history of franchise extension is a history of expansions and contractions. Much of the literature on the evolution of the right to vote builds on the following question: Why would a ruling elite decide to extend the suffrage to excluded groups who have different interests in the level of redistribution and the provision of public goods? Two competing theories dominate the debate: Bottom-up or demand theories emphasizing the role of revolutionary threats, and top-down or supply theories, explaining franchise extensions as the outcome of the strategic interactions of those in power and elites in the democratic opposition. A second question addresses the choice of a particular path of franchise extension, asking what explains different strategies and, in particular, the role of their accompanying institutional reforms. In contrast to the literature on the inclusion of the lower classes, women’s suffrage has been traditionally presented as the conquest of the suffragette movement. Current research, however, departs from this exceptionalism of female suffrage and shows certain consensus in explaining women’s suffrage as a political calculus, in which men willingly extend the franchise when they expect to benefit from it. Arguments differ though in the specific mechanisms that explain the political calculus. Finally, the literature on compulsory voting addresses the estimations of its impact on turnout; whether it translates into more efficient campaigning, improved legitimacy, and better representativity; and ultimately its effects on policies.

scholarly journals Blaise Pascal’s Mechanical Calculator: Geometric Modelling and Virtual Reconstruction

Machines ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 136
Author(s):  
José Ignacio Rojas-Sola ◽  
Gloria del Río-Cidoncha ◽  
Arturo Fernández-de la Puente Sarriá ◽  
Verónica Galiano-Delgado
Keyword(s):  
Computer Aided Design ◽  
Technological Development ◽  
Three Dimensional ◽  
3D Modelling ◽  
Blaise Pascal ◽  
Qualitative Information ◽  
3D Cad ◽  
Final Assembly ◽  
Virtual Reconstruction ◽  
Aided Design

This article shows the three-dimensional (3D) modelling and virtual reconstruction of the first mechanical calculating machine used for accounting purposes designed by Blaise Pascal in 1642. To obtain the 3D CAD (computer-aided design) model and the geometric documentation of said invention, CATIA V5 R20 software has been used. The starting materials for this research, mainly the plans of this arithmetic machine, are collected in the volumes Oeuvres de Blaise Pascal published in 1779. Sketches of said machine are found therein that lack scale, are not dimensioned and certain details are absent; that is, they were not drawn with precision in terms of their measurements and proportions, but they do provide qualitative information on the shape and mechanism of the machine. Thanks to the three-dimensional modelling carried out; it has been possible to explain in detail both its operation and the final assembly of the invention, made from the assemblies of its different subsets. In this way, the reader of the manuscript is brought closer to the perfect understanding of the workings of a machine that constituted a major milestone in the technological development of the time.

Z-line degradation and phagocytosis of sarcomeric fragments in myonecrosis

1983 ◽  
Vol 41 ◽  
pp. 790-791
Author(s):  
Melinda L. Estes ◽  
Samuel M. Chou
Keyword(s):  
Vastus Lateralis ◽  
Inflammatory Myopathy ◽  
Muscle Disease ◽  
White Female ◽  
Inflammatory Cell Infiltrate ◽  
Limb Weakness ◽  
Muscle Diseases ◽  
History Of ◽  
The Right ◽  
Mononuclear Inflammatory Cell

Many muscle diseases show common pathological features although their etiology is different. In primary muscle diseases a characteristic finding is myofiber necrosis. The mechanism of myonecrosis is unknown. Polymyositis is a primary muscle disease characterized by acute and subacute degeneration as well as regeneration of muscle fibers coupled with an inflammatory infiltrate. We present a case of polymyositis with unusual ultrastructural features indicative of the basic pathogenetic process involved in myonecrosis.The patient is a 63-year-old white female with a one history of proximal limb weakness, weight loss and fatigue. Examination revealed mild proximal weakness and diminished deep tendon reflexes. Her creatine kinase was 1800 mU/ml (normal < 140 mU/ml) and electromyography was consistent with an inflammatory myopathy which was verified by light microscopy on biopsy muscle. Ultrastructural study of necrotizing myofiber, from the right vastus lateralis, showed: (1) degradation of the Z-lines with preservation of the adjacent Abands including M-lines and H-bands, (Fig. 1), (2) fracture of the sarcomeres at the I-bands with disappearance of the Z-lines, (Fig. 2), (3) fragmented sarcomeres without I-bands, engulfed by invading phagocytes, (Fig. 3, a & b ), and (4) mononuclear inflammatory cell infiltrate in the endomysium.

Popliteal artery thrombosis secondary to a tibial osteochondroma

VASA ◽  
2011 ◽  
Vol 40 (3) ◽  
pp. 251-255 ◽  
Author(s):  
Gruber-Szydlo ◽  
Poreba ◽  
Belowska-Bien ◽  
Derkacz ◽  
Badowski ◽  
...  
Keyword(s):  
Case Report ◽  
Magnetic Resonance Angiography ◽  
Popliteal Artery ◽  
Doppler Ultrasonography ◽  
Histopathological Examination ◽  
Previous History ◽  
Plain Radiography ◽  
Artery Thrombosis ◽  
History Of ◽  
The Right

Popliteal artery thrombosis may present as a complication of an osteochondroma located in the vicinity of the knee joint. This is a case report of a 26-year-old man with symptoms of the right lower extremity ischaemia without a previous history of vascular disease or trauma. Plain radiography, magnetic resonance angiography and Doppler ultrasonography documented the presence of an osteochondrous structure of the proximal tibial metaphysis, which displaced and compressed the popliteal artery, causing its occlusion due to intraluminal thrombosis..The patient was operated and histopathological examination confirmed the diagnosis of osteochondroma.

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