The evolution of water-breathing respiratory faculties in craniotes

2019 ◽  
pp. 170-176
Author(s):  
Steven F. Perry ◽  
Markus Lambertz ◽  
Anke Schmitz
Keyword(s):  
Ph Sensitive ◽  
Control Of Breathing ◽  
The Other ◽  
Progressive Change ◽  
Gill Structure

The major components of the respiratory faculty (gill structure, muscular ventilation, central heart and erythrocyte-containing blood, and pH-sensitive control of breathing) appear to have been present in craniotes from the very beginning. But the details are so different in the most basally radiating group, hagfish, corroborating that they separated very early from the stem line. In the other groups, progressive changes are seen in the structure of the gills, heart, haemoglobin, as well as in the control of breathing. In particular, a major and progressive change in gill structure is seen when comparing sharks to teleosts, with several intermediary forms realized.

Control of breathing in craniotes

2019 ◽  
pp. 164-169
Author(s):  
Steven F. Perry ◽  
Markus Lambertz ◽  
Anke Schmitz
Keyword(s):  
Muscle Contraction ◽  
Muscle Activity ◽  
Control Of Breathing ◽  
The Other ◽  
Air Breathing ◽  
Ventilatory Frequency ◽  
Blood Ph ◽  
Other Hand

Craniote gills are arranged sequentially along the pharynx and accordingly are ventilated from anterior to posterior by a wave of muscle contraction, beginning with the mouth. Each gill pair appears to have its own set of neurons in the brainstem that coordinate the muscle activity and stimulate the next gill pair in the sequence. This system appears to have been maintained from hagfish to teleosts. In tetrapods, on the other hand, various centres in the brainstem coordinate different phases of breathing: expiration, inspiration, and post-inspiration. The location of these centres in the brainstem is similar in amphibians and mammals. The stimulus for regulating ventilatory frequency in water-breathing species is oxygen, whereas for air-breathing species it is blood pH/PCO2—just as in invertebrates.

The structure and properties of carded cotton vortex yarns

2012 ◽  
Vol 82 (7) ◽  
pp. 708-718 ◽  
Author(s):  
Nazan Erdumlu ◽  
Bulent Ozipek ◽  
William Oxenham
Keyword(s):  
Structural Analysis ◽  
Physical Properties ◽  
Average Length ◽  
The Other ◽  
Critical Parameters ◽  
Structure And Properties ◽  
Progressive Change ◽  
Spun Yarns ◽  
Yarn Count ◽  
Structural Classes

The properties and spinning limits of carded cotton vortex spun yarns were investigated through the progressive change in yarn count. The yarns were tested for structural and physical properties. Critical parameters were obtained, including the ratio of wrapper fibers to core fibers, proportion and average length of different structural classes in the yarn. The structural analysis revealed that the wrapper fibers constitute an increasing proportion of the fibers as the yarn becomes finer. Moreover, the proportion and average length of different structural classes in vortex spun yarns change with yarn count. The analysis of the data obtained from yarn testing showed that as the yarn becomes finer, the yarn becomes more uneven and the number of yarn imperfections markedly increase. On the other hand, the tensile properties of vortex spun yarns remain almost unchanged as the yarn gets finer.

Symmetry

2018 ◽  
Author(s):  
Peter John Glanville
Keyword(s):  
The Other ◽  
Progressive Change ◽  
Diverse Range ◽  
Symmetric Relation ◽  
Resistance Risk ◽  
Symmetric Structure ◽  
Participant Roles ◽  
Vowel Lengthening ◽  
The Difference ◽  
Semantic Typology

Chapter 5 determines the semantic typology of patterns III and VI, sometimes termed the vowel-lengthening patterns. It asserts that verbs formed in these patterns are symmetrical predicates, denoting relations consisting of two complementary forces. It shows that the difference between the two patterns results from the interplay between an underlying symmetric relation and a figure–ground orientation in which one of the participant roles involved is made more prominent than the other. The chapter divides verbs formed in pattern III into verbs of resistance, risk, competition, interaction, and co-action, and those formed in pattern VI into reciprocal verbs, feigning verbs, chaining verbs, and verbs of progressive change. It argues that an account based on a common symmetric structure is able to unite this diverse range of verbs within one analysis, and it offers data from other languages to support this claim.

Can the ‘Subaltern’ Ride? A Reply to O'Hanlon and Washbrook

1992 ◽  
Vol 34 (1) ◽  
pp. 168-184 ◽  
Author(s):  
Gyan Prakash
Keyword(s):  
Nineteenth Century ◽  
Third World ◽  
Status Quo ◽  
Point Of View ◽  
The Other ◽  
Progressive Change ◽  
The Third ◽  
Set Up ◽  
The Third World ◽  
Mode Of Production

The problem with Prakash, O'Hanlon and Washbrook conclude, is that he tries to ride two horses at once—one Marxist, the other poststructuralist deconstructionist. ‘But one of these may not be a horse that brooks inconstant riders. …’ So, they say we must choose only one to ride on, not both because the two, in their view, have opposing trajectories. One advances historical understanding and progressive change, the other denies history and perpetuates a retrogressive status quo. Posed in this manner, the choices involve more than a dispute over which paradigm provides a better understanding of the histories of the third world and India. At stake is the writing of history as political practice, and the only safe bet, from their point of view, is Marxism (of their kind), not the endless deferral and nihilism of deconstruction and postmodernism. Having set up this opposition, O'Hanlon and Washbrook's either/or logic has no place for the productive tension that the combination of Marxist and deconstructive approaches generates. They are uncomfortable with those recent writings that employ Marxist categories to analyze patterns of inequalities and exploitation while also using deconstructive approaches to contend that Marxism is part of the history that institutionalized capitalist dominance—approaches which argue that although Marxism can rightfully claim that it historicizes the emergence of capitalism as a world force, it cannot disavow its history as a nineteenth-century European discourse that universalized the mode-of-production narrative.

Progressive change in peripapillary atrophy in myopic glaucomatous eyes

2018 ◽  
Vol 102 (11) ◽  
pp. 1527-1532 ◽  
Author(s):  
Min Kyung Song ◽  
Kyung Rim Sung ◽  
Joong Won Shin ◽  
Junki Kwon ◽  
Ji Yun Lee ◽  
...  
Keyword(s):  
Optic Disc ◽  
The Other ◽  
Mean Deviation ◽  
Proportional Hazard ◽  
Progressive Change ◽  
Factors Associated ◽  
Cox Proportional Hazard ◽  
Peripapillary Atrophy ◽  
The Relationship

AimTo evaluate the progressive change in peripapillary atrophy (PPA) according to its shape and to explore the relationship between PPA progression and glaucoma worsening in myopic eyes.MethodsA total of 159 eyes of 159 patients with myopic (axial length (AXL) >24 mm) glaucoma (mean follow-up 4.4 years, 35 eyes with minimal PPA, 40 concentric-type PPA eyes (>270° around the optic disc) and 84 eccentric-type PPA eyes (<270°)) were included. Sequential stereoscopic colour optic disc photographs were evaluated to qualitatively determine PPA progression. Factors associated with PPA progression were explored by Cox proportional hazard modelling in each PPA group.ResultsPatients with concentric PPA were older than patients with eccentric PPA (54.1±11.7 vs 44.1±11.7 years; P<0.001), and AXL was longer in the eccentric group than in the other groups (25.54±1.68 vs 25.28±1.53 vs 26.41±1.29 mm; P<0.001). Twenty-six eyes (65%) in the concentric group and 36 eyes (42.9%) in the eccentric group showed PPA progression. Older age (hazard ratio (HR) 1.059, P=0.008), worse baseline visual field mean deviation (HR 0.857, P=0.009) and greater baseline PPA area (HR 1.000, P=0.012) were associated with PPA progression in the concentric type. Glaucoma progression (HR 3.690, P=0.002) and longer AXL (HR 1.521, P=0.002) were associated with PPA progression in the eccentric type.ConclusionsRelationship between glaucoma worsening and PPA progression was strongest in myopic glaucomatous eyes with eccentric type PPA.

EFFECT OF pH ON THE BINDING OF THYROXINE TO SERUM PROTEINS

1970 ◽  
Vol 65 (3) ◽  
pp. 409-422 ◽  
Author(s):  
Theodore Coutsoftides ◽  
Amirav Gordon
Keyword(s):  
Serum Albumin ◽  
Serum Proteins ◽  
Binding Capacity ◽  
Ph Sensitive ◽  
The Other ◽  
Rat Serum ◽  
Effect Of Ph ◽  
Thyroxine Binding Globulin ◽  
Other Hand ◽  
Maximal Binding

ABSTRACT The maximal binding capacity of human thyroxine-binding globulin (TBG) was found to decrease, and that of thyroxine-binding pre-albumin (TBPA) to increase with an increase in pH in the range of pH 7.2 to 8.2. On the other hand, the transfer of T4125I from the serum to a weak binder (Sephadex) was found to decrease with increasing pH. The same phenomena was shown to exist in mouse and rat serum, and to be blocked by DNP, a potent TBA & TBPA binding inhibitor. It is suggested that serum albumin may play a pH sensitive role in the T4 transfer to tissue.

Indian Debates on the International Left: Selected Writings of Lajpat Rai

2021 ◽  
Author(s):  
Shirin Rai ◽  
Anand Prakash
Keyword(s):  
Identity Politics ◽  
The Other ◽  
Right Wing ◽  
Progressive Change ◽  
Political Debates ◽  
Right Wing Populism ◽  
1960S And 1970S ◽  
The 1960S ◽  
The One

This book traces the Indian Left’s engagement with the international communist debates of the 1960s and 1970s, shedding new light on the fault lines within the Left as well as on its international solidarities. Lajpat Rai argued for rethinking established leftist positions, seeking inspiration in experiment and developing creative approaches for the sustainability of socialist ideas and ideals. The contemporary relevance of these debates is significant as the Left remains without a sharp response to the rise of neoliberalism and right-wing populism in India, and a failure of the Left to recognize the challenges emanating from a strongly integrated and organized finance capital on the one hand and the increasingly self-aware identity politics on the other. Democratic opposition rather than a bureaucratic thinking needs to be the backbone of any meaningful Left struggle. Lajpat Rai’s passionate writing gives expression to the spirit and intensity of political debates at the time and the role of the Left intelligentsia in comprehending, from a committed socialist angle, the shifting paradigms of an unstable world to help bring about progressive change.

scholarly journals Differences between three inbred rat strains in number of K+ channel-immunoreactive neurons in the medullary raphé nucleus

2010 ◽  
Vol 108 (4) ◽  
pp. 1003-1010 ◽  
Author(s):  
D. Riley ◽  
M. Dwinell ◽  
B. Qian ◽  
K. L. Krause ◽  
J. M. Bonis ◽  
...  
Keyword(s):  
Ph Sensitive ◽  
The Other ◽  
Female Rats ◽  
Male Rats ◽  
Cresyl Violet ◽  
Brown Norway ◽  
K Channel ◽  
Rat Strains ◽  
Medullary Raphe ◽  
Inbred Rat

Ventilatory sensitivity to hypercapnia is greater in Dahl salt-sensitive (SS) rats than in Fawn Hooded hypertensive (FHH) and Brown Norway (BN) inbred rats. Since pH-sensitive potassium ion (K+) channels are postulated to contribute to the sensing and signaling of changes in CO2-H+ in chemosensitive neurons, we tested the hypothesis that there are more pH-sensitive K+ channel-immunoreactive (ir) neurons within the medullary raphé nuclei of the highly chemosensitive SS rats than in the other two strains. Medullary tissues from male and female BN, FHH, and SS rats were stained with cresyl violet or with antibodies targeting TASK-1, Kv1.4, and Kir2.3 channels. K+ channel-ir neurons were quantified and compared with the total neurons in the region. The total number of neurons in the medullary raphé 1) was greater in male FHH than the other male rats, 2) did not differ among the female rats, and 3) did not differ between sexes. The average number of K+ channel-ir neurons per section was 30–60 neurons higher in the male SS than in the other rat strains. In contrast, for the females, the number of K+ channel-ir neurons was greatest in the BN. We also found significant differences in the number of K+ channel-ir neurons between sexes in SS (males > females) and BN (females > males) rats, but not the FHH strain. Our findings support the hypothesis for males but not for females, suggesting that both genetic background and sex are determinants of K+ channel immunoreactivity of medullary raphé neurons, and that the expression of pH-sensitive K+ channels in the medullary raphé does not correlate with the ventilatory sensitivity to hypercapnia.

Structural Mechanical and Tribological Behavior of Reactive Sputtered Cr-N and Cr-V-N Films

2018 ◽  
Vol 18 ◽  
pp. 27-34
Author(s):  
Linda Aissani ◽  
Mamoun Fellah ◽  
Corinne Nouveau
Keyword(s):  
Wear Resistance ◽  
Elastic Modulus ◽  
Mechanical Behavior ◽  
Tribological Behavior ◽  
The Other ◽  
Progressive Change ◽  
Other Hand ◽  
Adhesion Performance

CrVN coatings between 10 and 26 at.-% V were prepared by PVD to investigate the effect of V on the properties of CrN system. The films were analysed using, DRX, X microanalysis, AFM SEM, scratch, tribometer and nanoindentation testers.The DRX spectrum shows the formation of (CrN-VN) phases and the examinations morphology show that the progressive change in the structure mode with adding V. The study of mechanical behavior shows degradation in the hardness and elastic modulus. On the other hand, the Cr-V-N film has a good wear resistance which remains lower than that of CrN film. Detachment of the Cr-V-N layer is observed at the all scratch trace while the CrN film exhibits best adhesion performance.

scholarly journals A role for the Kölliker-Fuse nucleus in cholinergic modulation of breathing at night during wakefulness and NREM sleep

2010 ◽  
Vol 109 (1) ◽  
pp. 159-170 ◽  
Author(s):  
J. M. Bonis ◽  
S. E. Neumueller ◽  
K. L. Krause ◽  
T. Kiner ◽  
A. Smith ◽  
...  
Keyword(s):  
Cerebrospinal Fluid ◽  
Receptor Antagonist ◽  
Pulmonary Ventilation ◽  
Nrem Sleep ◽  
Control Of Breathing ◽  
The Other ◽  
Breathing Frequency ◽  
Dialysis Fluid ◽  
Tegmental Nuclei ◽  
Parabrachial Nuclei

For many years, acetylcholine has been known to contribute to the control of breathing and sleep. To probe further the contributions of cholinergic rostral pontine systems in control of breathing, we designed this study to test the hypothesis that microdialysis (MD) of the muscarinic receptor antagonist atropine into the pontine respiratory group (PRG) would decrease breathing more in animals while awake than while in NREM sleep. In 16 goats, cannulas were bilaterally implanted into rostral pontine tegmental nuclei ( n = 3), the lateral ( n = 3) or medial ( n = 4) parabrachial nuclei, or the Kölliker-Fuse nucleus (KFN; n = 6). After >2 wk of recovery from surgery, the goats were studied during a 45-min period of MD with mock cerebrospinal fluid (mCSF), followed by at least 30 min of recovery and a second 45-min period of MD with atropine. Unilateral and bilateral MD studies were completed during the day and at night. MD of atropine into the KFN at night decreased pulmonary ventilation and breathing frequency and increased inspiratory and expiratory time by 12–14% during both wakefulness and NREM sleep. However, during daytime studies, MD of atropine into the KFN had no effect on these variables. Unilateral and bilateral nighttime MD of atropine into the KFN increased levels of NREM sleep by 63 and 365%, respectively. MD during the day or at night into the other three pontine sites had minimal effects on any variable studied. Finally, compared with MD of mCSF, bilateral MD of atropine decreased levels of acetylcholine and choline in the effluent dialysis fluid. Our data support the concept that the KFN is a significant contributor to cholinergically modulated control of breathing and sleep.

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