On the Curriculum of Mathematics

1910 ◽  
Vol 3 (1) ◽  
pp. 1-8
Author(s):  
Eugene R. Smith ◽  
Jonathan T. Rorer ◽  
Isaac J. Schwatt

The student must thoroughly understand the meaning and the philosophy, so to speak, of each mathematical concept presented to him. It takes a long time before he familiarizes himself so thoroughly with the conceptions of any mathematical subject so that he gets their significance, meaning and spirit, and the ability and facility to apply them readily. Few students have a clear understanding of the quantitative meaning and significance of the theorems of proportion, such as: “A line drawn parallel to a side of a triangle divides the other sides proportionally,” or, “Similar triangles are to each other as the squares of the homologous sides.” In all my experience I have not received from a pupil a satisfactory explanation of the truth that one divided by infinity is equal to zero, a conception used in secondary mathematics. The same is true of college mathematics. Few students who have studied Analytical Geometry are able to give the true meaning, for instance, of the equation of the straight line, y = sx + m, i. e., that the ordinate of any point of the straight line is m greater than s times the abscissa of the point. These instances may be multiplied to quite an extent.

Author(s):  
A.J. Verkleij

Freeze-fracturing splits membranes into two helves, thus allowing an examination of the membrane interior. The 5-10 rm particles visible on both monolayers are widely assumed to be proteinaceous in nature. Most membranes do not reveal impressions complementary to particles on the opposite fracture face, if the membranes are fractured under conditions without etching. Even if it is considered that shadowing, contamination or fracturing itself might obscure complementary pits', there is no satisfactory explanation why under similar physical circimstances matching halves of other membranes can be visualized. A prominent example of uncomplementarity is found in the erythrocyte manbrane. It is wall established that band 3 protein and possibly glycophorin represents these nonccmplanentary particles. On the other hand a number of membrane types show pits opposite the particles. Scme well known examples are the ";gap junction',"; tight junction, the luminal membrane of the bladder epithelial cells and the outer membrane of Escherichia coli.


2010 ◽  
Vol 19 (1-2) ◽  
pp. 127-147 ◽  
Author(s):  
Krister Hertting

Leading with Pedagogical Tact- a Challenge in Children's Sports in Sweden The purpose of this article is to elucidate and problemize meetings between children and leaders in children's sport. The competitive sport is high valuated in the Swedish society and sport for children is central in the Swedish youth politics. The foundation in Swedish sport, as well as in the other Nordic countries, has for a long time relied on voluntary commitment. Approximately 650 000 people are voluntary engaged as leaders in sport in Sweden and 70% of children between 7 and 14 years compete in sports clubs. There is, however, a tension in the Swedish sport system. The sports for children has double missions - ‘association nurturing’ and ‘competition nurturing’, missions which are not always in harmony. In the daily activity it is the voluntary leaders who have to deal with these missions, which creates a field of tension. In this article I argue for a bridge between these missions by a leadership based on pedagogical tact. The empirical outlook is a narrative based on statements from leaders, children and parents in a study dealing with voluntary leadership within children's football. In the end I argue that focusing on this bridge is a win-win situation, both for children and sports.


Author(s):  
Anna Varnayeva

Coordinative constructions are traditionally opposed to subordinative constructions. However, this opposition comes down to denial of dependence in coordinative constructions. Thereby the parity of these two constructions does not come to light: subordinative construction can be described without coordinative one. This situation is not improved by detection of a coordinative triangle in all coordinative constructions. The article shows a new approach in the study of coordinative constructions: a coordinative construction is a system; there are not only specific relations – a coordinative triangle, – but also specific elements. Novelty of the study consists in the address to extralinguistic facts, viz. a mathematical concept of a set and its elements. There are a lot of similarities between them. A set in mathematics includes generalizing elements and the composed row in coordinative constructions; in the first case the set is not partitioned, in the second case it is partitioned. In mathematics equivalent components in coordinative constructions correspond to the set elements. A characteristic property in mathematics is homogeneity in coordinative constructions and etc. It is firstly demonstrated, that coordinative and subordinative constructions are correlative and the study of one construction is impossible without the study of the other one. Their parity is shown in coordinative constructions with elements of one set, in subordinative ones with elements of different sets. Cf.: roses and tulips –red roses. In the coordinatiму construction elements of one set are called: «flowers »; in the subordinative construction there are elements of different sets: «flowers » and «colors». It should be noted that the mathematical concept of a set relates to so called logical aspect in linguistics or thinking about reality.


2014 ◽  
pp. 691-697
Author(s):  
Suleiman José Hassuani

The sugarcane industry for a long time has focused only on the cane juice, its extraction and conversion to sugar. Bagasse was considered a residue and burnt inefficiently to generate steam and power. In the last decades, bagasse gradually started to be converted into energy in a more efficient way, supplying all the sugar industry energy needs (power, and steam) and, in some cases, significant excess electricity has been exported to the grid, becoming another important source of revenue. This motivated several studies of more advanced energy generation systems to boost energy exports. In more recent years, technologies called 2nd and 3rd generation have taken over the scene with many options, promising to convert biomass into more valuable products such as biofuels, chemicals, fertilisers, pellets, etc. Unfilled expectations and opportunities are rising. On the other hand, these technologies are competing for the same biomass, and this has to be considered. The industry has started to question ‘which way to go’, strategy and investment wise. The present study provides a broad scenario for the biomass availability, and its employment, with a close view to the main processes and products that might have an important role in the future of the biomass in the sugarcane industry.


Symmetry ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1134
Author(s):  
Kenta Higuchi ◽  
Takashi Komatsu ◽  
Norio Konno ◽  
Hisashi Morioka ◽  
Etsuo Segawa

We consider the discrete-time quantum walk whose local dynamics is denoted by a common unitary matrix C at the perturbed region {0,1,⋯,M−1} and free at the other positions. We obtain the stationary state with a bounded initial state. The initial state is set so that the perturbed region receives the inflow ωn at time n(|ω|=1). From this expression, we compute the scattering on the surface of −1 and M and also compute the quantity how quantum walker accumulates in the perturbed region; namely, the energy of the quantum walk, in the long time limit. The frequency of the initial state of the influence to the energy is symmetric on the unit circle in the complex plain. We find a discontinuity of the energy with respect to the frequency of the inflow.


2019 ◽  
Vol 10 (9) ◽  
pp. 555-561
Author(s):  
Louise Rosenmayr-Templeton

This industry update features a round-up of pharmaceutical news in May 2019 based on press releases and websites. The month was characterized by the achievement of significant milestones in gene therapy. The biggest of these was the US FDA’s approval of Zolgensma®. This medicine sums up the promise and price of genetic medicine. On one hand the clinical results show Zolgensma can dramatically improve the prognosis for infants with spinal muscular atrophy after just one administration, while on the other, it has been priced at around US$2.1 million. With more such therapies likely to reach the market, the debate on Zolgensma goes beyond cost, to overall affordability, the true meaning of cost–effectiveness and how to reward companies for effective, innovative medicines.


2019 ◽  
Vol 11 (10) ◽  
pp. 2824-2849 ◽  
Author(s):  
Paweł Mackiewicz ◽  
Adam Dawid Urantówka ◽  
Aleksandra Kroczak ◽  
Dorota Mackiewicz

Abstract Mitochondrial genes are placed on one molecule, which implies that they should carry consistent phylogenetic information. Following this advantage, we present a well-supported phylogeny based on mitochondrial genomes from almost 300 representatives of Passeriformes, the most numerous and differentiated Aves order. The analyses resolved the phylogenetic position of paraphyletic Basal and Transitional Oscines. Passerida occurred divided into two groups, one containing Paroidea and Sylvioidea, whereas the other, Passeroidea and Muscicapoidea. Analyses of mitogenomes showed four types of rearrangements including a duplicated control region (CR) with adjacent genes. Mapping the presence and absence of duplications onto the phylogenetic tree revealed that the duplication was the ancestral state for passerines and was maintained in early diverged lineages. Next, the duplication could be lost and occurred independently at least four times according to the most parsimonious scenario. In some lineages, two CR copies have been inherited from an ancient duplication and highly diverged, whereas in others, the second copy became similar to the first one due to concerted evolution. The second CR copies accumulated over twice as many substitutions as the first ones. However, the second CRs were not completely eliminated and were retained for a long time, which suggests that both regions can fulfill an important role in mitogenomes. Phylogenetic analyses based on CR sequences subjected to the complex evolution can produce tree topologies inconsistent with real evolutionary relationships between species. Passerines with two CRs showed a higher metabolic rate in relation to their body mass.


1878 ◽  
Vol 28 (2) ◽  
pp. 633-671 ◽  
Author(s):  
Alexander Macfarlane

The experiments to which I shall refer were carried out in the physical laboratory of the University during the late summer session. I was ably assisted in conducting the experiments by three students of the laboratory,—Messrs H. A. Salvesen, G. M. Connor, and D. E. Stewart. The method which was used of measuring the difference of potential required to produce a disruptive discharge of electricity under given conditions, is that described in a paper communicated to the Royal Society of Edinburgh in 1876 in the names of Mr J. A. Paton, M. A., and myself, and was suggested to me by Professor Tait as a means of attacking the experimental problems mentioned below.The above sketch which I took of the apparatus in situ may facilitate tha description of the method. The receiver of an air-pump, having a rod capable of being moved air-tight up and down through the neck, was attached to one of the conductors of a Holtz machine in such a manner that the conductor of the machine and the rod formed one conducting system. Projecting from the bottom of the receiver was a short metallic rod, forming one conductor with the metallic parts of the air-pump, and by means of a chain with the uninsulated conductor of the Holtz machine. Brass balls and discs of various sizes were made to order, capable of being screwed on to the ends of the rods. On the table, and at a distance of about six feet from the receiver, was a stand supporting two insulated brass balls, the one fixed, the other having one degree of freedom, viz., of moving in a straight line in the plane of the table. The fixed insulated ball A was made one conductor with the insulated conductor of the Holtz and the rod of the receiver, by means of a copper wire insulated with gutta percha, having one end stuck firmly into a hole in the collar of the receiver, and having the other fitted in between the glass stem and the hollow in the ball, by which it fitted on to the stem tightly. A thin wire similarly fitted in between the ball B and its insulating stem connected the ball with the insulated half ring of a divided ring reflecting electrometer.


2013 ◽  
Vol 834-836 ◽  
pp. 1290-1294
Author(s):  
Xin Qin Liu

Mechanicalmethods were employed to study the motion and force transmission performance ofa kind of connecting rod slider mechanism with a curved edge driving component.The deduction methods and the computation formulae of the slider displacement,velocity, acceleration and the executive force gain coefficient were given.Considering two cases of the driving components with straight line edge andexponential function edge, the numerical examples was computed respectively,the results show that the former one is suitable for the force transmission andcan be used in the grip design and the other one is suitable for the motiontransmission which can be used in the fast moving mechanism


Author(s):  
Koen De Temmerman ◽  
Danny Praet

This chapter explores martyr accounts. Scholars traditionally divide these texts into two types: narrative representations of the suffering and death of martyrs (the so-called passiones) on the one hand, and dramatic representations of the trial preceding this (the so-called acta or praxeis), on the other. The exact semantic range of both labels is debated, but in any case the distinction does not capture the textual reality in its full complexity: even the predominantly narrative texts often contain an interrogation scene, whereas most so-called acta always have a narrative frame, however minimal it may be. In addition, there is no formal unity across the board. This chapter first addresses some of the intellectual premisses that in traditional scholarship on martyr acts were for a long time conducive of historical questions, much to the detriment of the study of these texts as narratives in their own right. The chapter then observes that many martyr acts recount not only the deaths of their protagonists but also cover (parts of) their preceding lives, and it explores how these texts adopt and adapt narrative and rhetorical protocols from traditional life-writing to shape the lives of their protagonists. Finally, attention is paid briefly to the thematic cluster of erotic love, desire, marriage, and the preservation of chastity that drives many such narrative elaborations. It is concluded that whereas research on these texts has long been driven by historical interests, they are also treasure-troves for scholars interested in narrative in general and life-writing in particular.


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