scholarly journals Cytoskeletal Tensegrity in Microgravity

Life ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1091
Author(s):  
John Gardiner

In order for Man to venture further into Space he will have to adapt to its conditions, including microgravity. Life as we know it has evolved on Earth with a substantial gravitational field. If they spend considerable time away from Earth, astronauts experience physiological, mental, and anatomical changes. It is not clear if these are pathological or adaptations. However, it is true that they experience difficulties on their return to stronger gravity. The cytoskeleton is a key site for the detection of gravitational force within the body, due to its tensegrity architecture. In order to understand what happens to living beings in space, we will need to unravel the role cytoskeletal tensegrity architecture plays in the building and function of cells, organs, the body, and mind.

2020 ◽  
Vol 27 (3) ◽  
pp. 201-209
Author(s):  
Syed Saqib Ali ◽  
Mohammad Khalid Zia ◽  
Tooba Siddiqui ◽  
Haseeb Ahsan ◽  
Fahim Halim Khan

Background: Ascorbic acid is a classic dietary antioxidant which plays an important role in the body of human beings. It is commonly found in various foods as well as taken as dietary supplement. Objective: The plasma ascorbic acid concentration may range from low, as in chronic or acute oxidative stress to high if delivered intravenously during cancer treatment. Sheep alpha-2- macroglobulin (α2M), a human α2M homologue is a large tetrameric glycoprotein of 630 kDa with antiproteinase activity, found in sheep’s blood. Methods: In the present study, the interaction of ascorbic acid with alpha-2-macroglobulin was explored in the presence of visible light by utilizing various spectroscopic techniques and isothermal titration calorimetry (ITC). Results: UV-vis and fluorescence spectroscopy suggests the formation of a complex between ascorbic acid and α2M apparent by increased absorbance and decreased fluorescence. Secondary structural changes in the α2M were investigated by CD and FT-IR spectroscopy. Our findings suggest the induction of subtle conformational changes in α2M induced by ascorbic acid. Thermodynamics signatures of ascorbic acid and α2M interaction indicate that the binding is an enthalpy-driven process. Conclusion: It is possible that ascorbic acid binds and compromises antiproteinase activity of α2M by inducing changes in the secondary structure of the protein.


Author(s):  
Steven N. Dworkin

This book describes the linguistic structures that constitute Medieval or Old Spanish as preserved in texts written prior to the beginning of the sixteenth century. It emphasizes those structures that contrast with the modern standard language. Chapter 1 presents methodological issues raised by the study of a language preserved only in written sources. Chapter 2 examines questions involved in reconstructing the sound system of Old Spanish before discussing relevant phonetic and phonological details. The chapter ends with an overview of Old Spanish spelling practices. Chapter 3 presents in some detail the nominal, verbal, and pronominal morphology of the language, with attention to regional variants. Chapter 4 describes selected syntactic structures, with emphasis on the noun phrase, verb phrase, object pronoun placement, subject-verb-object word order, verb tense, aspect, and mood. Chapter 5 begins with an extensive list of Old Spanish nouns, adjectives, verbs, and function words that have not survived into the modern standard language. It then presents examples of coexisting variants (doublets) and changes of meaning, and finishes with an overview of the creation of neologisms in the medieval language through derivational morphology (prefixation, suffixation, compounding). The book concludes with an anthology composed of three extracts from Spanish prose texts, one each from the thirteenth, fourteenth, and fifteenth centuries. The extracts contain footnotes that highlight relevant morphological, syntactic, and lexical features, with cross references to the relevant sections in the body of the book.


Parasitology ◽  
1924 ◽  
Vol 16 (1) ◽  
pp. 111-112
Author(s):  
Edward Hindle

In December, 1922, whilst dissecting a large female example of Bufo regularis, one of my students noticed a cylindrical structure extending along the ventral region of the body-cavity. A careful examination showed that this structure consisted of an elongated sac-like diverticulum of the right lung, containing an almost full-grown specimen of a dipterous larva, which could be seen through the membraneous wall of the diverticulum. The base of the latter, in addition to its point of origin from the lung, was also connected to the dorsal surface of the liver by strands of fibrous tissue, suggesting that the growth had been in existence some considerable time in order to cause such adhesions. Posteriorly, the diverticulum hung freely in the body cavity and extended to the extreme hinder end. Its dimensions were 5·5 cm. in length, by 0·5 cm. in diameter, but tapering towards each extremity.


2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Shanta Pandian ◽  
Kamal Narayan Arya ◽  
Dharmendra Kumar

Background. Balance and functional abilities are controlled by both sides of the body. The role of nonparetic side has never been explored for such skills.Objective. The objective of the present study was to examine the effect of a motor therapy program primarily involving the nonparetic side on balance and function in chronic stroke.Method. A randomized controlled, double blinded trial was conducted on 39 poststroke hemiparetic subjects (21, men; mean age, 42 years; mean poststroke duration, 13 months). They were randomly divided into the experimental group(n=20)and control group(n=19). The participants received either motor therapy focusing on the nonparetic side along with the conventional program or conventional program alone for 8 weeks (3 session/week, 60 minutes each). The balance ability was assessed using Berg Balance Scale (BBS) and Functional Reach Test (FRT) while the functional performance was measured by Barthel Index (BI).Result. After intervention, the experimental group exhibited significant(P<0.05)change on BBS (5.65 versus 2.52) and BI (12.75 versus 2.16) scores in comparison to the control group.Conclusion. The motor therapy program incorporating the nonparetic side along with the affected side was found to be effective in enhancing balance and function in stroke.


Author(s):  
Greg Quinn

There are many theoretical models that attempt to accurately and consistently link kinematic and kinetic information to musculoskeletal pain and deformity of the foot. Biomechanical theory of the foot lacks a consensual model: clinicians are enticed to draw from numerous paradigms, each having different levels of supportive evidence and contrasting methods of evaluation, in order to engage in clinical deduction and treatment planning. Contriving to find a link between form and function lies at the heart of most of these competing theories and the physical nature of the discipline has prompted an engineering approach. Physics is of great importance in biology and helps us to model the forces that the foot has to deal with in order for it to work effectively. However, the tissues of the body have complex processes that are in place to protect them and they are variable between individuals. Research is uncovering why these differences exist and how these processes are governed. The emerging explanations for adaptability of foot structure and musculoskeletal homeostasis offer new insights on how clinical variation in outcomes and treatment effects might arise. These biological processes underlie how variation in the performance and utilisation of common traits, even within apparently similar sub-groups, make anatomical distinction less meaningful and are likely to undermine the justification of a 'foot type'. Furthermore, mechanobiology introduces a probabilistic element to morphology based on genetic and epigenetic factors.


Geophysics ◽  
1952 ◽  
Vol 17 (2) ◽  
pp. 344-364 ◽  
Author(s):  
Fraser S. Grant

A method is developed for determining the approximate size and shape of the three‐dimensional mass distribution that is required to produce a given gravitational field. The first few reduced multipole moments of the distribution are calculated from the derivatives of the surface field, and the approximative structure is determined from the values of these moments and a knowledge of the density contrast between the body and its surroundings. A system of classification of problems by symmetry is introduced and its practical usage discussed. A relaxation method is described which may be used to adjust the initial solution systematically to give agreement over the whole field. A descriptive discussion is appended.


Open Physics ◽  
2016 ◽  
Vol 14 (1) ◽  
pp. 395-409 ◽  
Author(s):  
Mayeul Arminjon

AbstractAn alternative, scalar theory of gravitation has been proposed, based on a mechanism/interpretation of gravity as being a pressure force: Archimedes’ thrust. In it, the gravitational field affects the physical standards of space and time, but motion is governed by an extension of the relativistic form of Newton’s second law. This implies Einstein’s geodesic motion for free particles only in a constant gravitational field. In this work, equations governing the dynamics of a continuous medium subjected to gravitational and non-gravitational forces are derived. Then, the case where the non-gravitational force is the Lorentz force is investigated. The gravitational modification of Maxwell’s equations is obtained under the requirement that a charged continuous medium, subjected to the Lorentz force, obeys the equation derived for continuum dynamics under external forces. These Maxwell equations are shown to be consistent with the dynamics of a “free” photon, and thus with the geometrical optics of this theory. However, these equations do not imply local charge conservation, except for a constant gravitational field.


1998 ◽  
Vol 28 (3) ◽  
pp. 655-663 ◽  
Author(s):  
P. NOPOULOS ◽  
M. FLAUM ◽  
S. ARNDT ◽  
N. ANDREASEN

Background. Morphometry, the measurement of forms, is an ancient practice. In particular, schizophrenic somatology was popular early in this century, but has been essentially absent from the literature for over 30 years. More recently, evidence has grown to support the notion that aberrant neurodevelopment may play a role in the pathophysiology of schizophrenia. Is the body, like the brain, affected by abnormal development in these patients?Methods. To evaluate global deficit in development and its relationship to pre-morbid function, height was compared in a large group (N=226) of male schizophrenics and a group of healthy male controls (N=142) equivalent in parental socio-economic status. Patients in the lower quartile of height were compared to those in the upper quartile of height.Results. The patient group had a mean height of 177·1 cm, which was significantly shorter than the mean height of the control group of 179·4 (P<0·003). Those in the lower quartile had significantly poorer pre-morbid function as measured by: (1) psychosocial adjustment using the pre-morbid adjustment scales for childhood and adolescence/young adulthood, and (2) cognitive function using measures of school performance such as grades and need for special education. In addition, these measures of pre-morbid function correlated significantly with height when analysed using the entire sample.Conclusions. These findings provide further support to the idea that abnormal development may play a key role in the pathophysiology of schizophrenia. Furthermore, this is manifested as a global deficit in growth and function resulting in smaller stature, poorer social skills, and deficits in cognitive abilities.


2019 ◽  
Vol 8 (1) ◽  
pp. 56-61
Author(s):  
Siti Fithrotul Umami ◽  
Titiek Idayanti

Background: Development is increasing ability (skill) in the structure and function of the body that is more complex in a regular pattern and can be predicted as a result, from the results of maturation. attitude is an individual evaluation in the form of a tendency (Inclination) towards various elements outside of him. Based on the results of a preliminary study of 10 children aged 5-6 years, it was found that 5 children had normal development, 2 children doubted, and 3 children developed abnormally. While for family education conducted by parents, it was found that 7 parents supported (favorabel), and 3 parents were not supportive (unfavorable).Objectives: The study aimed to determine the influence of parents' attitudes in providing education at home toward the development of children aged 5-6 years in Bulusari Village, Gempol Sub-District, Pasuruan District.Methods: The research design was analytical design using purposive sampling with a sample of 45 parents and children in Bulusari Village, Gempol Sub-District, Pasuruan District. The measuring instrument used was a questionnaire for parents and KPSP for child development. This research is presented in the form of the Fisher's Exact Test.Results: The results showed that of 38 parents (84.45%) who supported having normal development children as many as 35 children (77.78%). Based on the results of the Fisher's Exact Test statistical test, it was found that the value of p <α, which is 0.001022 <0.05, which means that there is an influence from the provision of family education conducted by parents to the development of children aged 5-6 years.Conclusion: Based on the results of this study, it is expected that efforts from health workers to increase counseling to parents so that they have a role and have an obligation to help, assist children, teach children to actively learn, give love, develop creativity and socialization of children. Kata kunci : Parent’s attitude, development of 5-6 years, giving education in houses.


Author(s):  
Tony Yuan

The relative velocity between objects with finite velocity affects the reaction between them. This effect is known as general Doppler effect. The Laser Interferometer Gravitational-Wave Observatory (LIGO) discovered gravitational waves and found their speed to be equal to the speed of light c. Gravitational waves are generated following a disturbance in the gravitational field; they affect the gravitational force on an object. Just as light waves are subject to the Doppler effect, so are gravitational waves. This article explores the following research questions concerning gravitational waves: What is the spatial distribution of gravitational waves? Can the speed of a gravitational wave represent the speed of the gravitational field (the speed of the action of the gravitational field upon the object)? What is the speed of the gravitational field? Do gravitational waves caused by the revolution of the Sun affect planetary precession? Can we modify Newton&rsquo;s gravitational equation through the influence of gravitational waves?


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