A ‘Hyaline’ Layer in the Skin of Squids

1997 ◽  
Vol 77 (4) ◽  
pp. 1247-1250 ◽  
Author(s):  
J.J. Madan ◽  
M.J. Wells

The skin of Loligo vulgaris and Illex illecebrosus contains a thick layer of amorphous material. In Loligo it lies above and in Illex below the chromatophore layer. We can find no mention of this layer in the considerable literature on squid skins despite its potential importance as a protection to underlying tissues and as a possible barrier to cutaneous oxygen uptake.Cephalopods have soft complicated skins. Embedded in the skin, most species have chromatophores, small bags of pigment that can be expanded by muscles that are under direct nervous control from the brain. There is an extensive literature on the physiology of chromatophores (Packard, 1988) and on their function in the behaviour of the animals (Hanlon & Messenger, 1996; Packard & Hochberg, 1977). Further cutaneous structures concerned in the determination of the colour of living cephalopods, the reflecting iridophores and leucophores (Cloney & Brocco, 1983), and the light generating photophores (Herring, 1988), have been the subject of a number of reports but other skin features such as the distribution of blood vessels have attracted little attention.

In the course of my investigations on the Pineal Apparatus of the Tuatara ( Sphenodon punctas ) I have found it desirable to make as complete a study as possible of the arrangement of the intracranial arteries and veins, of which no description has as yet been published. As any facts relating to the structure of Sphenodon are of more than usual interest, and as I hope to be able to give a more complete account of the subject than has yet been given for any reptile, I have decided to offer my results for publication as a separate memoir, without waiting for the completion of my work on the pineal organs. The blood-vessels have been investigated partly by dissection and partly by means of serial sections, and such completeness of detail as I have been able to attain is very largely due to the adoption of a method of fixing and hardening which I have found to have many advantages both for the study of the vascular system and of the brain itself. By this method the entire contents of the cranial cavity are fixed and hardened in situ , and are then in excellent condition either for dissection or for histological purposes. The application of the method in the case of Sphenodon is greatly facilitated by the fact that the brain does not occupy nearly the whole of the cranial cavity, a large subdural space being left, especially above the brain, across which numerous blood-vessels run, together with delicate strands of connective tissue which connect the dura mater with the pia .


1917 ◽  
Vol 63 (260) ◽  
pp. 93-98
Author(s):  
John Cruickshank

The marked complexity of the convolutions of the brain of man, as compared with the lower animals, has suggested to numerous writers that the higher intellectual and other mental faculties characteristic of the human subject are in more or less direct relationship to the amount of grey matter in the brain. Attempts have therefore been made to measure the amount of grey matter in the brains of persons of very different degrees of intelligence and mental development. Owing to the highly complicated nature of the convolutions of the human brain, the method of estimation by direct dissection of the grey matter from the underlying white matter has not been adopted except in the case of a very few brains, most workers having approached the subject by indirect methods. Some observers have directed their attention to the measurement of the surface area of the grey matter, others to the determination of the absolute amount of cortex. Danilewsky, as a result of observations upon the specific gravity of the brain and of the grey and white matter, has calculated that the cortex forms 30 per cent. of the total brain weight. Donaldson, on the other hand, has estimated the grey matter of the hemisphere as forming 50 per cent. of the whole.


1935 ◽  
Vol 31 (1) ◽  
pp. 136-136
Author(s):  
J. Kligler ◽  
L. Olitzki

Aa., citing the extensive literature available on the subject, indicate that the brain was usually injected in the amount of 0.1-0.3, giving equivalent results: either the pathogen was killed by this method of brain processing and no immunity was achieved, or the virus could not be killed and then a typical infection occurred, which naturally communicated immunity to the animal.


2020 ◽  
pp. 23-33
Author(s):  
Elena A. Zaeva-Burdonskaya ◽  
Yuri V. Nazarov

This article addresses one of the most actively developing types of design activities – light design. The article comprises quotes of the leading Russian and foreign light design specialists published over the previous five years, as well as the authors’ own conclusions. The thoughts quoted in the article are sometimes opposite to each other and reflect the wide spectrum of professional practice. They reflect the initial opinions of analysts and experts which are often diverging. All of the specialists point at the interdisciplinary nature of the new profession, which imposes additional load on a designer overloaded enough already by the scope and speed of the problems being solved nowadays. The discussion of the new profession of light designer initiated on the pages of professional publications is especially important in view of the development of professional standards and standards of design and architectural education, as well as creation of new educational programmes based on various approaches to the subject in technical and humanitarian institutions. The goal of this article is to introduce light design into the field of fully legitimate sections of design culture, to define the authentic scientific basis of the new creative profession, to initiate a foundation for self-determination of the new synthetic area, which materially affects the state of the profession as a whole and the life standards of a wide variety of consumers. In order to reach the set goal, a comparative and analytical method of study was selected, which allows studying the problem to a large extent and from all angles and finding the ways of overcoming the challenges emerging in the area of the new activity.


Author(s):  
Evgeniya Mikhailovna Popova ◽  
Guzel Mukhtarovna Guseinova ◽  
Sergei Borisovich Milov

The deficit of subnational budgets and deceleration capital investments in multiple Russian regions increase the relevance of research aimed at improvement of tax incentivizing practice of the regional investment process. The studies focused on determination of the impact of socioeconomic and institutional factors upon the efficiency of investment tax expenses obtained wide circulation within the foreign scientific literature. The subject of this article is the assessment of sensitivity of the efficiency of regional tax expanses towards investment attractiveness of the types of economic activity carried out by the residents of territories of advanced socioeconomic development, created in the subjects of Far Easter Federal District. The scientific novelty and practical values of this research consists in substantiation of the reasonableness of assessment of investment attractiveness of the types of economic activity that are stimulated by tax incentives. Methodology for assessing investment attractiveness is proposed and tested. The conclusion is made that in case of low investment attractiveness of the type of economic activity, which was planned to support by tax incentives, it is required to conduct and additional analysis to avoid unjustified tax expanses.


2018 ◽  
Vol 25 (28) ◽  
pp. 3333-3352 ◽  
Author(s):  
Natalia Pessoa Rocha ◽  
Ana Cristina Simoes e Silva ◽  
Thiago Ruiz Rodrigues Prestes ◽  
Victor Feracin ◽  
Caroline Amaral Machado ◽  
...  

Background: The Renin-Angiotensin System (RAS) is a key regulator of cardiovascular and renal homeostasis, but also plays important roles in mediating physiological functions in the central nervous system (CNS). The effects of the RAS were classically described as mediated by angiotensin (Ang) II via angiotensin type 1 (AT1) receptors. However, another arm of the RAS formed by the angiotensin converting enzyme 2 (ACE2), Ang-(1-7) and the Mas receptor has been a matter of investigation due to its important physiological roles, usually counterbalancing the classical effects exerted by Ang II. Objective: We aim to provide an overview of effects elicited by the RAS, especially Ang-(1-7), in the brain. We also aim to discuss the therapeutic potential for neuropsychiatric disorders for the modulation of RAS. Method: We carried out an extensive literature search in PubMed central. Results: Within the brain, Ang-(1-7) contributes to the regulation of blood pressure by acting at regions that control cardiovascular functions. In contrast with Ang II, Ang-(1-7) improves baroreflex sensitivity and plays an inhibitory role in hypothalamic noradrenergic neurotransmission. Ang-(1-7) not only exerts effects related to blood pressure regulation, but also acts as a neuroprotective component of the RAS, for instance, by reducing cerebral infarct size, inflammation, oxidative stress and neuronal apoptosis. Conclusion: Pre-clinical evidence supports a relevant role for ACE2/Ang-(1-7)/Mas receptor axis in several neuropsychiatric conditions, including stress-related and mood disorders, cerebrovascular ischemic and hemorrhagic lesions and neurodegenerative diseases. However, very few data are available regarding the ACE2/Ang-(1-7)/Mas receptor axis in human CNS.


2019 ◽  
Vol 15 (2) ◽  
pp. 121-129
Author(s):  
Zhi Rao ◽  
Bo-xia Li ◽  
Yong-Wen Jin ◽  
Wen-Kou ◽  
Yan-rong Ma ◽  
...  

Background: Imatinib (IM) is a chemotherapy medication metabolized by CYP3A4 to Ndesmethyl imatinib (NDI), which shows similar pharmacologic activity to the parent drug. Although methods for determination of IM and/or NDI have been developed extensively, only few observations have been addressed to simultaneously determine IM and NDI in biological tissues such as liver, kidney, heart, brain and bone marrow. Methods: A validated LC-MS/MS method was developed for the quantitative determination of imatinib (IM) and N-desmethyl imatinib (NDI) from rat plasma, bone marrow, brain, heart, liver and kidney. The plasma samples were prepared by protein precipitation, and then the separation of the analytes was achieved using an Agilent Zorbax Eclipse Plus C18 column (4.6 × 100 mm, 3.5 µm) with gradient elution running water (A) and methanol (B). Mass spectrometric detection was achieved by a triplequadrupole mass spectrometer equipped with an electrospray source interface in positive ionization mode. Results: This method was used to investigate the pharmacokinetics and the tissue distributions in rats following oral administration of 25 mg/kg of IM. The pharmacokinetic profiles suggested that IM and NDI are disappeared faster in rats than human, and the tissue distribution results showed that IM and NDI had good tissue penetration and distribution, except for the brain. This is the first report about the large penetrations of IM and NDI in rat bone marrow. Conclusion: The method demonstrated good sensitivity, accuracy, precision and recovery in assays of IM and NDI in rats. The described assay was successfully applied for the evaluation of pharmacokinetics and distribution in the brain, heart, liver, kidney and bone marrow of IM and NDI after a single oral administration of IM to rats.


2019 ◽  
pp. 129-136 ◽  
Author(s):  
E. A. Khorova ◽  
A. V. Myshlyavtsev

The subject of the study were rubber mixtures based on hydrogenated butadiene-nitrile rubbers (HNBR) Therban, Zetpol, NBR-B with an acrylonitrile (AN) content of 34% to 49% and unsaturation of 0.9% to 22% with sulfuric, peroxide and sulfuric-peroxide cure systems. The purpose of the study was to determine the effect of the AN content and the degree of unsaturation of HNBR on the properties of rubbers in products designed for operation under the influence of fuels and oils at increased temperatures.The results of the determination of the mass swelling of rubbers in hydrocarbon media and the relative elongation in the process of thermal aging in air and in oil at increased temperatures are presented. The conclusion was made on the use of HNBR mixture with maximum content of AN (49%), with low (6%) and extremely low (0.9%) ODS content and sulfuric peroxide cure system to extend the product service temperature limit to 150°C.


Author(s):  
Chakravarthi Ram-Prasad

The Introduction outlines the various chapters. It then situates the question of ‘body’ in the modern Western philosophical tradition following Descartes, and argues that this leaves subsequent responses to come under one of three options: metaphysical dualism of body and subject; any anti-dualist reductionism; or the overcoming of the divide. Describing the Phenomenology of Merleau-Ponty as a potent example of the third strategy, the Introduction then suggests his philosophy will function as foil to the ecological phenomenology developed and presented in the book. Moreover, one approach within the Western Phenomenological tradition, of treating phenomenology as a methodology for the clarification of experience (rather than the means to the determination of an ontology of the subject) is compared to the approach in this book. Since classical India, while understanding dualism, did not confront the challenge of Descartes (for better or for worse), its treatment of body follows a different trajectory.


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