scholarly journals A closer analysis of the heat production of nerve

The heat production of nerve is believed to occur in two phases, “initial” and “recovery”; the former is presumably an accompaniment of the physical and chemical changes which take place during the propagation of the nerve restored to its initial state. It is not easy to separate the one from the other ; indeed, during the earlier part of this research it was realised that in a strict sense, and on the evidence available, there might really be no “initial” heat at all. This is made clear by the following discussion.

2008 ◽  
Vol 19 (3) ◽  
pp. 273-291
Author(s):  
Milotka Molnar-Sivc

Although the question of relationship between basic concepts of traditional ontology and central concepts of fundamental ontology is not a topic which is systematically dealt with in Being and Time, it is obvious that some of the theses which are crucial not only for Heidegger's interpretation of philosophical tradition, but also for the whole project of fundamental ontology, concern this 'conceptual scheme'. In fact, the backbone of Heidegger's critical confrontation with dominant philosophical conceptions is the question of relationship between the concept of 'substance' and the concept of 'Being', i.e. the discussion of philosophical doctrines in which 'Being' is reduced to 'substance'. Besides this context, which concerns the ontological problematics in the strict sense, it is possible to show that the refutation of the basic categories of traditional ontology is an issue which has a decisive role in more concrete phases of the realization of the project of fundamental ontology. This is especially confirmed in Heidegger's discussion of the concept of 'Being-There'. The interpretation of Heidegger's treatment of the relationship between the concepts of 'Being-there', 'existence' and 'existentials' on the one hand, and the concepts of 'substance', 'essence' and 'categories' on the other, shows that one of Heidegger's basic theses is that a transformation of concepts of traditional ontology is necessary for an appropriate understanding of human being.


Previous papers have dealt with the homogeneous catalysis of the decomposition of ethers and of acetaldehyde by iodine. The problem of the mechanism of these catalysed reactions can be approached in two ways: on the one hand, by seeking to obtain as complete a picture as possible of the types of chemical change which are susceptible to the action of a given catalyst, and, the catalysts which will promote a given chemical change; and, on the other hand, by investigating in detail the kinetics and molecular statistics of individual reactions. Experiments on the different kinds of reaction which iodine will catalyse are being published elsewhere. Most of the chemical changes have involved too many side reactions, or secondary reactions with the catalyst, to be suitable for complete kinetic analysis. Nevertheless, they show the chemical specificity of the action of iodine in the clearest manner, and this aspect of the problem is discussed from a general point of view in the last section of the present paper.


2000 ◽  
Vol 21 (1-2) ◽  
pp. 86-103
Author(s):  
Dieter Wandschneider

AbstractThe Cartesian concept of nature, which has determined modem thinking until the present time, has become obsolete. It shall be shown that Hegel's objective-idealistic conception of nature discloses, in comparison to that of Descartes, new perspectives for the comprehension of nature and that this, in turn, results in possibilities of actualizing Hegel's philosophy of nature.If the argumentation concerning philosophy of nature is intended to catch up with the concrete Being-of-nature and to meet it in its concretion, then this is impossible for the finite spirit in a strictly a priori sense — this is the thesis supported here which is not at all close to Hegel. As the argumentation rather has to consider the conditions of realization concerning the Being-of-nature, too, it is compelled to take up empirical elements — concerning the organism, for instance, system-theoretical aspects, physical and chemical features of the nervous system, etc. With that, on the one hand, empirical-scientific premises are assumed (e.g. the lawlikeness of nature), which on the other hand become (now close to Hegel) possibly able to be founded in the frame of a Hegelian-idealistic conception. In this sense, a double strategy of empirical-scientific concretization and objective-idealistic foundation is followed up, which represents the methodical basic principle of the developed considerations.In the course of the undertaking, the main aspects of the whole Hegelian design concerning the philosophy of nature are considered — space and time, mass and motion, force and law of nature, the organism, the problem of evolution, psychic being — as well as Hegel's basic thesis concerning the philosophy of nature, that therein a tendency towards coherence and idealization manifests itself in the sense of a (categorically) gradually rising succession of nature: from the separateness of space to the ideality of sensation. In the sense of the double strategy of concretization and foundation it is shown that on the one hand possibilities of philosophical penetration concerning actual empirical-scientific results are opened, and on the other hand — in tum — a re-interpretation of Hegel's theorem on the basis of physical, evolution-theoretical and system-theoretical argumentation also becomes possible. In this mutual crossing-over and elucidation of empirical and Hegelian argumentation not only do perspectives of a new comprehension of nature become visible, but also, at the same time — as an essential consequence of this methodical principle — thoughts on the possibilities of actualizing Hegel's philosophy of nature.


1958 ◽  
Vol 149 (935) ◽  
pp. 167-175 ◽  

Non-medullated nerve . In a single impulse at 0 °C the heat production occurs in two phases, positive and negative. Records were made of the heat during repetitive stimulation at various frequencies. With 5 shocks/s the diphasic character of the heat was evident, with 10 shocks/s the instruments were too slow to show it, as they are above about 12 °C at any frequency. But the two phases probably occur under all conditions. Medullated nerve . No indication was obtained that the heat production in medullated nerve is diphasic : but this may well be due to the instruments being too slow to separate the phases. During a short tetanus at 0 °C the rate of heat production rises apparently abruptly at the start, and falls equally suddenly at the end, of the stimulus. This is the most probable interpretation of the records, but it remains possible that a short delay (0.02 to 0.04 s) may occur between an impulse and the corresponding heat production: at room temperature this could not be more than about 0.01 s. The magnitude of the heat production is considered in relation to the possibility that activity during an impulse occurs only in the nodal region.


Phainomenon ◽  
2017 ◽  
Vol 26 (1) ◽  
pp. 155-183
Author(s):  
Roberto Terzi

Abstract The issue of the event and its relation to the concept of phenomenon has been widely spread in the French phenomenology of the last decades. Firstly, this article aims at retracing some general aspects of the role of the event in what has been called the “New phenomenology in France” and raises the problem of a distinction between different uses of this concept. Secondly, it analyses in two phases the presence of this topic in Marion’s phenomenology. On the one hand, it has to be shown that the concept of the event occupies an increasingly important role in Marion’s thinking, for it characterises givenness and phenomenality as such. On the other hand, I intend to problematize the position of Marion, in so far as it leads to an integral givenness and unfolds on the basis of an ambiguous overlap of the themes of givenness and intuition. Finally, Marion’s analysis will be contrasted to Derrida’s thinking, which allows us to think at the event as an impossible that happens, as a constitutive non-givenness and therefore as an essential limitation for phenomenology.


2021 ◽  
Vol 8 ◽  
Author(s):  
Ning Xu ◽  
Xue-Liang Peng ◽  
Hao-Ru Li ◽  
Jia-Xuan Liu ◽  
Ji-Si-Yu Cheng ◽  
...  

Collagen is a kind of biocompatible protein material, which is widely used in medical tissue engineering, drug delivery, cosmetics, food and other fields. Because of its wide source, low extraction cost and good physical and chemical properties, it has attracted the attention of many researchers in recent years. However, the application of collagen derived from terrestrial organisms is limited due to the existence of diseases, religious beliefs and other problems. Therefore, exploring a wider range of sources of collagen has become one of the main topics for researchers. Marine-derived collagen (MDC) stands out because it comes from a variety of sources and avoids issues such as religion. On the one hand, this paper summarized the sources, extraction methods and characteristics of MDC, and on the other hand, it summarized the application of MDC in the above fields. And on the basis of the review, we found that MDC can not only be extracted from marine organisms, but also from the wastes of some marine organisms, such as fish scales. This makes further use of seafood resources and increases the application prospect of MDC.


2006 ◽  
Vol 2006 (1) ◽  
pp. 5-20 ◽  
Author(s):  
Petra Gehring

There are two phases in the philosophy of the 20. and the beginning 21. century, in which not generally ‚the world‘, but actually issues like ‚land and sea‘, ‚land and air‘, ‚land and earth‘ became philosophical references. There are on the one hand the diagnoses of geopolitical crises in the 1950th and there is on the other hand the so-called ‚spatial turn‘ of the cultural sciences and related contemporary philosophy. The article presents two exemplary positions: the geo-philosophical reflections of Carl Schmitt as well as the considerations of Peter Sloterdijk in connection with his analyses of globalization. The article doesn’t intend an final appraisal of the subject matter (or the works of both authors). Following the guideline of Husserls considerations about „earth“ is however asked, which function may have the phenomenon (and topic) of a concretized spatiality in the context of the two exemplary presented philosophical diagnoses. What makes ‚land‘ or ‚space‘ attractive to Schmitt and Sloterdijk?


The heat production of stimulated nerve occurs in two main stages, initial and recovery. The first object of this paper is to define and distinguish the initial heat more clearly; the second is to present fresh evidence that the recovery heat occurs in two phases, the first complete in a few seconds, the second only in 30 minutes. Since an earlier paper (Hill, 1932, a ) was written, various attempts have been made to quicken up the recording system of thermopile and galvanometer, so as to secure a sharper analysis of the heat. A new thermopile has been constructed by Mr. A. C. Downing, with soldered constantan-iron couples and bakelite insulation. It is no more sensitive than the old one, but possesses the great advantage for some purposes that it is so well shielded from heat leaking from the stimulating electrodes that a correction is seldom necessary.


KronoScope ◽  
2016 ◽  
Vol 16 (2) ◽  
pp. 187-198
Author(s):  
Étienne Klein

One hundred and fifty years after the work of Ludwig Boltzmann on the interpretation of the irreversibility of physical phenomena, we are still not sure what we mean when we talk of “time” or the “arrow of time.” One source of this difficulty is our tendency to confuse time and becoming: that is, the course of time and the arrow of time, two concepts that the formalisms of physics do distinguish clearly. The course of time is represented by a line on which it is customary to place a small arrow that, ironically, must not be confused with the “arrow of time.” On the one hand, this small arrow indicates that the course of time is oriented. On the other hand, the arrow of time indicates the possibility for physical systems to experience, over the course of time, changes or transformations that prevent them from returning to their initial state forever.


2015 ◽  
Vol 68 (1) ◽  
pp. 7471-7479 ◽  
Author(s):  
Edilson León Moreno Cárdenas ◽  
Carlos Eugenio Oliveros Tascón ◽  
Fernando Álvarez Mejía

The harvest is one of the most important activities in coffee crops; on the one hand, it provides employment opportunities for a large group of rural workers and on the other, it supplies mature fruits for the production of high quality coffee. In the present study, a device was designed and evaluated to assist in manual coffee harvesting, called Alfa, which employs a three-toothed blade beater, a DC motor powered by dry batteries and a system for receiving detached fruits. The research proceeded in two phases; in the first, the device was designed and built; in the second, an evaluation was carried out by using traditional manual collection as a comparison. The evaluations were developed in four locations: three experimental stations of Cenicafé and one private property. The variables studied were: number of fruits left on the ground after harvest, percentage of immature coffee in the harvested mass and yield. The device presented an operating time of four days without recharging, a weight less than four kg and an absence of technical failures; the operators had no problems with its use; and, in addition, it was possible to increase the yield of the operators by almost 70%; the percentage of immature coffee was between 4.5% and 3% and losses were between one and 19 fruits per site.


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