scholarly journals Compensatory hypertrophy of the untreated ovary after unilateral X-ray sterilisation

1929 ◽  
Vol 105 (734) ◽  
pp. 36-42
Keyword(s):  
Corpus Luteum ◽  
Compensatory Hypertrophy ◽  
Point Of View ◽  
The Other ◽  
X Rays ◽  
X Ray ◽  
Pregnancy And Lactation ◽  
The Right

The technique of sterilising one ovary and allowing the other ovary to remain untreated was originally evolved (Parkes, 8) in order to make possible the accurate study of the rôle of the corpus luteum during pregnancy and lactation. Early in the experiments, however, it was noticed that litters from such unilaterally sterilised mice approximated closely to the normal size. It was later found that, with one ovary sterilised by X-rays, the other ovary undergoes true compensatory hypertrophy, such as has been observed by many authors to follow unilateral or sub-total ovariotomy (1, 4, 5, 6). Since the facts appeared to be of interest from the point of view of the mechanism of compensatory hypertrophy, the experiments on the corpus luteum were so arranged as to permit of collecting the data required to demonstrate hypertrophy of the reamining ovary. II.— Methods and Material . Sterilisation Technique .—The method of carrying out these unilateral irradiations has been described elsewhere (Parkes, 8) and it need only be said here that irradiation took place at 4 weeks old, and that in every case the right ovary was exposed, while the left was protected.

The Discovery of X-Rays: a Probable Case of Second Order Observation

2018 ◽  
Vol 19 (4) ◽  
pp. 403
Author(s):  
Marco Aurélio Clemente Gonçalves ◽  
Mariele Regina Pinheiro Gonçalves ◽  
Pablo Eduardo Ortiz
Keyword(s):  
History Of Science ◽  
Second Order ◽  
Point Of View ◽  
X Rays ◽  
Historical Reconstruction ◽  
X Ray ◽  
Probable Case ◽  
The Status ◽  
History Of

The discovery of x-rays, one of the most beautiful experiments ever carried out, generates numerous controversies and these, in turn, can trigger a series of counterproductive information regarding not only the History of Science but also the teaching  activity. The aim of this article is to resolve these controversies concerning what ocurred and highlight the important role of the German physicist Wilhelm Conrad Röntgen, highlighting not only his genius but, especially in this case in particular, his condition of second-order observer. It is not uncommon to find information in various media refering to this discovery under the claim that it was the result of a fortuitous event, and this denotes a profound lack of knowledge about the facts or a disrespect for the renowned discoverer. Such allegations about the event depreciate the extraordinary discovery that impacts humanity, from the deed  to the present. Thus, through a brief historical reconstruction, it was tried to present here what had happened judiciously. With this respect, the brilliant scientist is given the status of a second-rate observer, from the philosophical point of view. This condition resonates with the diachronic aspect of the History of Science, according to the perspective presented here, and it is also supported by the time taken by the discoverer from the beginning of his research until the end of it. Keywords: X-Ray. Second-Order Observer. History of Science. ResumoO descobrimento dos raios-x, um dos mais belos experimentos já realizados, gera inúmeras controvérsias e essas, por sua vez, podem desencadear uma série de informações contraproducentes no tangente não só a História da Ciência como também à atividade de ensino. O presente artigo tem como objetivo dirimir tais polêmicas com respeito ao ocorrido e destacar o importante papel do físico alemão Wilhelm Conrad Röntgen, destacando não só sua genialidade, mas sobretudo, neste caso em particular, a sua condição de observador de segunda ordem. Não é raro encontrar em diversos meios de comunicação informações com respeito a referida descoberta sob a alegação de que a mesma fora fruto de um caso fortuito e isso denota profundo desconhecimento sobre os fatos, ou então, desrespeito com o renomado descobridor. Tais alegações sobre o sucedido depreciam a descoberta extraordinária que impacta a humanidade, desde o feito até a atualidade. Assim, através de breve reconstrução histórica, buscou-se aqui apresentar o ocorrido criteriosamente. Com este respeito passa-se a atribuir ao brilhante cientista a condição de observador de segunda ordem, do ponto de vista filosófico. Tal condição encontra ressonância no aspecto diacrônico da História da Ciência, segundo a perspectiva aqui apresentada e está amparada, também, pelo tempo empreendido pelo descobridor desde o início de sua pesquisa até a finalização da mesma. Palavras-chave: Raios-x. Observador de Segunda Ordem. História da Ciência.

scholarly journals Changes in the ovary of the mouse following exposure to X-Rays. Part IV.— The corpus luteum in the sterilized ovary, and some concluding experiments

1928 ◽  
Vol 102 (719) ◽  
pp. 385-396 ◽  
Keyword(s):  
Corpus Luteum ◽  
Degenerative Changes ◽  
Corpora Lutea ◽  
X Rays ◽  
X Ray ◽  
General Manner ◽  
Pregnancy And Lactation

The previous papers of. this series dealt only in a brief and general manner with the effect of X-ray sterilization on the corpora lutea. The present paper, the last of the series, includes more extensive work aimed at removing this deficiency. The work was begun by irradiating pregnant animals, but owing to the technical difficulties the greater part of it was carried out on lactating animals. In this paper it will be shown that the degenerative changes in the corpora lutea of pregnancy and lactation take place very slowly after sterilization, although they begin at the normal time. The corpora lutea become, in fact, practically permanent structures. The oestrous cycles of both these series of animals are dealt with elsewhere (9) by one of us, where it is shown that these “permanent” corpora lutea do not retain their oestrous-inhibiting power for any appreciable period after what would be the functional life of the normal corpus luteum. Moreover, the possible duration of lactation is not affected by sterilization at the beginning of suckling. The histology of the ovaries discussed in this paper is essentially similar to that found in the animals previously described (1,2, and 3) and need not be dealt with at length.

scholarly journals On the distribution of intensity in the X-ray spectra of certain long-chain organic compounds

1925 ◽  
Vol 108 (748) ◽  
pp. 655-666 ◽  
Keyword(s):  
Single Molecule ◽  
Complete Solution ◽  
Point Of View ◽  
The Other ◽  
Active Group ◽  
X Rays ◽  
Simple Interpretation ◽  
X Ray ◽  
The One ◽  
Long Chain

Recently, many compounds, having as the basis of their structure a long chain of carbon atoms, have been investigated by means of X-rays. Although the complete solution of the crystal structure of these compounds presents great difficulties, certain measurements, which can readily be made, appear capable of a simple interpretation in terms of the molecular structure. It is found, for example, that there is one plane in the crystal which has a very much larger spacing than any of the others, and the magnitude of this spacing is very simply related to the number of carbon atoms in the molecule. In any series, as the molecular chain is increased by the continued addition of CH 2 groups, this spacing increases uniformly. This must mean that the molecules are oriented lengthwise between such planes, so that an increase in the length of the molecule results in a corresponding increase in the spacing. It does not follow that the molecules are so arranged that the direction of their length is perpendicular to these planes ; but, for any one series, the angle which this direction makes with the normal to the plane must remain very nearly constant; in certain series the molecules appear to be very nearly at right angles to the planes. A consideration of the results of many such measurements led to the conclusion that, from an X-ray point of view, the various series may be divided into two groups, ( a ) those in which the planes are separated by the length of a single molecule, ( b ) those in which the spacing corresponds to the length of two molecules. It is possible to predict with considerable certainty to which of these two classes a series will belong. If, at the end of the molecule, there is a group which is chemically active as in the cases of the fatty acids, alcohols, etc., series, it seems reasonable to conclude that, where the double length is found, the two molecules will be arranged end-to-end in opposite directions, the active group of the one molecule being oriented towards the active group of the other.

Digital x-ray mapping of nanometer-size supported bimetallic catalysts

1988 ◽  
Vol 46 ◽  
pp. 530-531
Author(s):  
L. T. Germinario
Keyword(s):  
Background Radiation ◽  
Metal Cluster ◽  
Single Element ◽  
Beam Diameter ◽  
X Rays ◽  
X Ray ◽  
Major Interest ◽  
Induced Changes

Understanding the role of metal cluster composition in determining catalytic selectivity and activity is of major interest in heterogeneous catalysis. The electron microscope is well established as a powerful tool for ultrastructural and compositional characterization of support and catalyst. Because the spatial resolution of x-ray microanalysis is defined by the smallest beam diameter into which the required number of electrons can be focused, the dedicated STEM with FEG is the instrument of choice. The main sources of errors in energy dispersive x-ray analysis (EDS) are: (1) beam-induced changes in specimen composition, (2) specimen drift, (3) instrumental factors which produce background radiation, and (4) basic statistical limitations which result in the detection of a finite number of x-ray photons. Digital beam techniques have been described for supported single-element metal clusters with spatial resolutions of about 10 nm. However, the detection of spurious characteristic x-rays away from catalyst particles produced images requiring several image processing steps.

Arthroscopy in Arthrosis: Is It Worth it? A case Presentation

2018 ◽  
Vol 69 (8) ◽  
pp. 2232-2235
Author(s):  
Marius Moga ◽  
Mark Edward Pogarasteanu ◽  
Antoine Edu
Keyword(s):  
Clinical Status ◽  
Loose Body ◽  
Point Of View ◽  
The Other ◽  
Joint Range Of Motion ◽  
Objective Evidence ◽  
Before And After ◽  
Total Knee ◽  
Joint Range

The role of arthroscopy in incipient and mild arthrosis, even combined with proximal tibial ostetomy, is well known and well documented. On the other hand, its role in the treatment of advanced arthrosis of the large joints, especially the knee, is a subject of controversy. The proponents of the use of arthroscopy in advanced arthrosis claim that meniscectomy, synovectomy, ostophytectomy, chondral lesion stabilization, arthroscopic release, plica and loose body removal greatly improve the quality of life for most patients, especially if followed by the use of viscoelastic injection, by diminishing pain and improving joint range of motion. The opponents claim that, even though the advantages are clear in the cases that refuse arthroplasty, in all the other cases the surgical indication should be total knee arthroplasty, as the clinical relief is temporary, but with all the risks of a surgical intervention. We have conducted an overview of the recent literature, in order to find objective evidence to sustain either point of view. We focused on articles published that included an objective measurement of before and after clinical status through clinical scores and objective measurements. We also focused on the follow-up period and on the evolution of the pathology after arthroscopy.

How Antisymmetric Is Syntax?

2003 ◽  
Vol 34 (3) ◽  
pp. 516-526 ◽  
Author(s):  
Yuji Takano
Keyword(s):  
Linear Order ◽  
Phrase Structure ◽  
Negative Polarity ◽  
Point Of View ◽  
The Other ◽  
Negative Polarity Items ◽  
Polarity Items ◽  
The Right

Since the emergence of Kayne's (1994) stimulating proposal for an antisymmetric theory of phrase structure and linear order, much work has been devoted to arguing for or against his theory as well as discussing its empirical predictions. As a result, for a number of phenomena involving rightward positioning, such as rightward adjuncts, heavy NP shift, extraposition, postverbal subjects, and postverbal constituents in OV languages, there now exist both an approach consistent with Kayne's theory (the antisymmetric approach) and another not consistent with it (the symmetric approach). In such a situation, it is often difficult to show on empirical grounds that one approach is superior to the other (see Rochemont and Culicover 1997). In what follows, I describe this situation with respect to two well-known phenomena in English: rightward positioning of adjuncts and heavy NP shift. For each of these phenomena, the symmetric and antisymmetric approaches have been proposed, and both approaches can correctly account for the data discussed in previous studies. Here, I examine the approaches from a novel point of view, showing that data involving the licensing of negative polarity items allow us to differentiate them and to decide which is the right one for each of the two empirical domains. Interestingly, the relevant facts lead to different conclusions for the two phenomena. The results have important implications for the antisymmetric view of syntax.

Role of sinoatrial ring bundle in internodal conduction

1976 ◽  
Vol 231 (2) ◽  
pp. 319-325 ◽  
Author(s):  
M Hiraoka ◽  
T Sano
Keyword(s):  
Sinus Node ◽  
The Other ◽  
Wave Fronts ◽  
Av Node ◽  
Crista Terminalis ◽  
Main Route ◽  
Endocardial Surface ◽  
The Right ◽  
Activation Sequence

The role of the sinoatrial ring bundle (SARB) in internodal conduction was examined by the microelectrode technique in excised rabbit hearts. The spread of the sinus impluse to the surrounding tissues was shown to proceed anteriorly toward the right branch of the crista terminalis significantly faster than toward the other direction. Thus the right SARB and the right branch of the crista terminalis close to the sinus node were the earliest areas excited by the sinus impulse in the areas surrounding the sinus node. It was further shown that the activation sequence does not initiate from the right SARB to the right branch of the crista terminalis via the junction of these two structures. Cutting the SARB did not produce any delay in conduction from the sinus node to the atrioventricular (AV) node. The conduction velocity measured at the endocardial surface by two microelectrodes has proved that conduction in the crista terminalis was significantly faster than in the SARB. The upstroke of the action potential from the crista terminalis was also steeper than that from the SARB. These results suggest that the SARB is not the main route for impulse propagation from the sinus node to the AV node; the fastest internodal conduction therefore takes place with wide wave fronts, along the crista terminalis.

scholarly journals Investigating the Magnetospheres of Rapidly Rotating B-type Stars

2016 ◽  
Vol 12 (S329) ◽  
pp. 369-372
Author(s):  
C. L. Fletcher ◽  
V. Petit ◽  
Y. Nazé ◽  
G. A. Wade ◽  
R. H. Townsend ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Centrifugal Force ◽  
Point Of View ◽  
Closed Field ◽  
Theoretical Point ◽  
X Rays ◽  
Rapid Rotation ◽  
X Ray ◽  
Surface Magnetic Field

AbstractRecent spectropolarimetric surveys of bright, hot stars have found that ~10% of OB-type stars contain strong (mostly dipolar) surface magnetic fields (~kG). The prominent paradigm describing the interaction between the stellar winds and the surface magnetic field is the magnetically confined wind shock (MCWS) model. In this model, the stellar wind plasma is forced to move along the closed field loops of the magnetic field, colliding at the magnetic equator, and creating a shock. As the shocked material cools radiatively it will emit X-rays. Therefore, X-ray spectroscopy is a key tool in detecting and characterizing the hot wind material confined by the magnetic fields of these stars. Some B-type stars are found to have very short rotational periods. The effects of the rapid rotation on the X-ray production within the magnetosphere have yet to be explored in detail. The added centrifugal force due to rapid rotation is predicted to cause faster wind outflows along the field lines, leading to higher shock temperatures and harder X-rays. However, this is not observed in all rapidly rotating magnetic B-type stars. In order to address this from a theoretical point of view, we use the X-ray Analytical Dynamical Magnetosphere (XADM) model, originally developed for slow rotators, with an implementation of new rapid rotational physics. Using X-ray spectroscopy from ESA’s XMM-Newton space telescope, we observed 5 rapidly rotating B-types stars to add to the previous list of observations. Comparing the observed X-ray luminosity and hardness ratio to that predicted by the XADM allows us to determine the role the added centrifugal force plays in the magnetospheric X-ray emission of these stars.

scholarly journals TOLERANSI ANTAR PENGANUT NAHDHATUL ULAMA, MUHAMMADIYAH, DAN KRISTEN JAWA DI BATANG

2013 ◽  
Vol 5 (1) ◽  
Author(s):  
Adistya Iqbal Irfani, ◽  
Moh. Yasir Alimi ◽  
Rini Iswari
Keyword(s):  
Research Method ◽  
Qualitative Method ◽  
Point Of View ◽  
The Other ◽  
Mixed Marriage ◽  
Mutual Support ◽  
Administrative Leaders ◽  
Religious Aspects ◽  
The Village

Tujuan penelitian ini adalah untuk mengeksplorasi bentuk toleransi dan faktor pendorong dan faktor penghambat toleransi masyarakat Jawa dengan studi kasus di Dukuh Medono Kabupaten Batang. Di dukuh tersebut, penganut organisasi agama seperti NU, Muhammadiyah dan Kristen Jawa di Dukuh Medono saling hidup rukun. Metode penelitian menggunakan metode penelitian kualitatif dengan pendekatan fenomenologi. Hasil penelitian menunjukan bahwa toleransi antar penganut NU, Muhammadiyah, Kristen Jawa tampak berbagai bentuk. Antara NU dan Kristen Jawa dalam bentuk partisipasi dalam ritual tahlilan, sedangkan antar ketiganya tampak dalam bentuk kerja bakti, saling membantu dalam acara hajatan, perkawinan campur dan saling berkunjung bila ada yang sakit. Faktor pendorong toleransi antara lain budaya toleransi yang sudah lama, pernikahan antar penganut yang berbeda, sosialisasi toleransi dalam keluarga, dan kepemimpinan desa yang menekankan pentingnya toleransi. Sedangkan faktor penghambat toleransi yaitu perbedaan pandangan antar penganut NU dan Muhammadiyah dalam pelaksanaan ibadah, pernikahan beda keyakinan, dan sikap menyinggung keyakinan diantara penganut yang ada. The objective of this study is to explore forms of tolerance and the driving factor of religious tolerance in Dukuh Medono, Batang. In that village, the followers of NU, Muhammadiyah, and Kristen Jawa live peacefully and united in tolerance. The research method used here is a qualitative method with phenomenology approach. The result of the research shows that the tolerance between NU followers and Javanese Christians take the form of participation in tahlilan ritual. The tolerance between NU, Muhammadiyah followers, and Kristen Jawa followers are expressed through kerja bakti, mutual support in hajatan rituals, mixed marriage, visits to the sick, and social activities together. The factors which help to create tolerance include the culture of tolerance which exist in the village, marriages between religious followers, the socialization of tolerance within family, the socialization of tolerance within the society and the role of village administrative leaders. On the other hand, the factors which distract tolerance are different point of view between NU dan Muhammadiyah followers in some religious aspects, marriage between different religious followers, and the attitude of insulting others beliefs.

scholarly journals Support of Road Freight Transport Especially in North-East Part of Schengen Borders

2015 ◽  
Vol 2 (3) ◽  
pp. 101-104
Author(s):  
Romana Hricová
Keyword(s):  
Freight Transport ◽  
Point Of View ◽  
Border Crossing ◽  
The Other ◽  
Just In Time ◽  
North East ◽  
Other Hand ◽  
Road Freight ◽  
Points Of View ◽  
The Right

Green logistics is very attractive and request the point of view. Many companies try to be “green”, but on the other hand they also must be quick, be in right time in the right place and everything with as low costs as possible. So because of it, they use more road freight transport. Nowadays road freight transport is much expanded as transport companies prefer the possibility to operate just-in-time.  There are several advantages that give road freight transport the first place. Firstly, the truck can be prepared whenever, no matter what time is chosen.  Secondly, the flexibility and no more borders with customs control inside the Schengen Area make freight transport quicker. On the other hand, innovative approaches ask for environmental protection, which becomes one of the most important points of view.  If countries support this environmental friendly transport, this would be reflected in the transport prices which should make rail transport more interesting. Using the methodology in the manuscript was divided to three steps. The first step is to identify relevant questions related to border crossing. Next step is to elaborate a list of border problems, and the last step is an analysis of available data.  

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