scholarly journals Nonequilibrium Entropy Conservation and the Transport Equations of Mass, Momentum, and Energy

Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2196
Author(s):  
Michael H. Peters
Keyword(s):  
Local Equilibrium ◽  
Nonequilibrium Statistical Mechanics ◽  
Critical Role ◽  
Nonequilibrium Thermodynamic ◽  
Transport Equations ◽  
Basis Set ◽  
Nonequilibrium Entropy ◽  
Complete Set ◽  
Entropy Conservation ◽  
Relationship Of

Nonequilibrium statistical mechanics or molecular theory has put the transport equations of mass, momentum and energy on a firm or rigorous theoretical foundation that has played a critical role in their use and applications. Here, it is shown that those methods can be extended to nonequilibrium entropy conservation. As already known, the “closure” of the transport equations leads to the theory underlying the phenomenological laws, including Fick’s Law of Diffusion, Newton’s Law of Viscosity, and Fourier’s Law of Heat. In the case of entropy, closure leads to the relationship of entropy flux to heat as well as the Second Law or the necessity of positive entropy generation. It is further demonstrated how the complete set of transport equations, including entropy, can be simplified under physically restrictive assumptions, such as reversible flows and local equilibrium flows. This analysis, in general, yields a complete, rigorous set of transport equations for use in applications. Finally, it is also shown how this basis set of transport equations can be transformed to a new set of nonequilibrium thermodynamic functions, such as the nonequilibrium Gibbs’ transport equation derived here, which may have additional practical utility.

scholarly journals Potential Functions and Thermodynamic Properties of UC, UN, and UH

2020 ◽  
Vol 2020 ◽  
pp. 1-6
Author(s):  
Shuang-Ling Tang ◽  
Yu Wang ◽  
Qi-Ying Xia ◽  
Xue-Hai Ju
Keyword(s):  
Configuration Interaction ◽  
Density Functional ◽  
Least Square Method ◽  
Potential Functions ◽  
Least Square ◽  
Basis Set ◽  
Dissociation Energies ◽  
Anharmonicity Constant ◽  
Different Temperatures ◽  
Relationship Of

Potential energy surface scanning for UC, UN, and UH was performed by configuration interaction (CI), coupled cluster singles and doubles (CCSD) excitation, quadratic configuration interaction (QCISD (T)), and density functional theory PBE1 (DFT-PBE1) methods in coupling with the ECP80MWB_AVQZ + 2f basis set for uranium and 6 − 311 + G∗ for carbon, hydrogen, and nitrogen. The dissociation energies of UC, UN, and UH are 5.7960, 4.5077, and 2.6999 eV at the QCISD (T) levels, respectively. The calculated energy was fitted to the potential functions of Morse, Lennard-Jones, and Rydberg by using the least square method. The anharmonicity constant of UC is 0.0047160. The anharmonic frequency of UC is 780.27 cm−1 which was obtained based on the PBE1 results. For UN, the anharmonicity constant is 0.0049827. The anharmonic frequency is 812.65 cm−1 which was obtained through the PBE1 results. For UH, the anharmonicity constant is 0.017300. The anharmonic frequency obtained via the QCISD (T) results is 1449.8 cm−1. The heat capacity and entropy in different temperatures were calculated using anharmonic frequencies. These properties are in good accordance with the direct DFT-UPBE1 results (for UC and UN) and QCISD (T) results (for UH). The relationship of entropy with temperature was established.

Medullary lateral tegmental field: control of respiratory rate and vagal lung inflation afferent influences on sympathetic nerve discharge

2005 ◽  
Vol 288 (5) ◽  
pp. R1396-R1410 ◽  
Author(s):  
Shaun W. Phillips ◽  
Gerard L. Gebber ◽  
Susan M. Barman
Keyword(s):  
Respiratory Rate ◽  
Sympathetic Nerve ◽  
Artificial Ventilation ◽  
Critical Role ◽  
Lung Inflation ◽  
Chemical Inactivation ◽  
A Value ◽  
Relationship Of ◽  
The Relationship ◽  
Nerve Discharge

We used spectral analysis and event-triggered averaging to determine the effects of chemical inactivation of the medullary lateral tegmental field (LTF) on 1) the relationship of intratracheal pressure (ITP, an index of vagal lung inflation afferent activity) to sympathetic nerve discharge (SND) and phrenic nerve activity (PNA) and 2) central respiratory rate in paralyzed, artificially ventilated dial-urethane-anesthetized cats. ITP-SND coherence value at the frequency of artificial ventilation was significantly ( P < 0.05; n = 18) reduced from 0.73 ± 0.04 (mean ± SE) to 0.24 ± 0.04 after bilateral microinjection of muscimol into the LTF. Central respiratory rate was unexpectedly increased in 12 of these experiments (0.28 ± 0.03 vs. 0.95 ± 0.25 Hz). The ITP-PNA coherence value was variably affected by chemical inactivation of the LTF. It was unchanged when central respiratory rate was also not altered, decreased when respiratory rate was increased above the rate of artificial ventilation, and increased when respiratory rate was raised from a value below the rate of artificial ventilation to the same frequency as the ventilator. Chemical inactivation of the LTF increased central respiratory rate in four of six vagotomized cats but did not significantly affect the PNA-SND coherence value. These data demonstrate that the LTF 1) plays a critical role in mediating the effects of vagal lung inflation afferents on SND but not PNA, 2) helps maintain central respiratory rate in the physiological range, but 3) is not involved in the coupling of central respiratory and sympathetic circuits.

Verb paradigm in Tomo Kan Dogon: interconnections of polypredicative constructions, grammaticalization, and tonology

2021 ◽  
pp. 252-268
Author(s):  
V. V. Dyachkov ◽  
Keyword(s):  
Critical Role ◽  
The Other ◽  
Anal Ysis ◽  
Syntactic Position ◽  
The Family ◽  
Similar Range ◽  
Tonal Contour ◽  
Relationship Of

The paper deals with the grammaticalization problems in Tomo Kan (Dogon family, Niger-Congo) and, in particular, with the diachronic relationship of polypredicative constructions and TAM markers. Dogon languages are characterized by TAM systems that seem to be dia-chronically unstable since markers with a similar range of meanings go back to different lexi-cal sources in different languages of the family. TAM markers are apparently associated with polypredicative constructions, which are very common in Dogon and preserve some of their morphosyntactic properties. At the same time, Dogon languages are characterized by complex tonal changes triggered not only by phonological context but also by the syntactic position of constituents. These tonal changes, frequently referred to as tonosyntax, accompany the formation of polypredicative constructions and other syntactic phenomena. A thorough inves-tigation of Tomo Kan TAM markers shows their tonosyntactic properties to resemble those of polypredicative constructions. Moreover, assuming that tonosyntax of polypredicative con-structions triggers certain tonal contour overlays, one can account for tonal alternations ob-served in TAM forms which would have been left otherwise unexplained. However, the anal-ysis also reveals that at least two classes of TAM forms must be distinguished in Tomo Kan: one of them inherits the tonosyntax of polypredicative constructions while the other does not. A hypothesis is put forward that the latter class has a different source of grammaticalization and is probably associated with verb stem incorporation rather than with polypredication. Methodologically, the paper shows a critical role of tonology in the analysis of grammaticalization processes in tonal languages.

scholarly journals Host Mediators in Gingival Crevicular Fluid: Implications for the Pathogenesis of Periodontal Disease

1992 ◽  
Vol 3 (1) ◽  
pp. 31-60 ◽  
Author(s):  
Ira B. Lamster ◽  
M. John Novak
Keyword(s):  
Immune Response ◽  
Periodontal Disease ◽  
Gingival Crevicular Fluid ◽  
Critical Role ◽  
Arachidonic Acid Metabolite ◽  
Reactive Oxygen Metabolites ◽  
Tissue Destruction ◽  
Crevicular Fluid ◽  
Relationship Of ◽  
The Relationship

During the past few years, a considerable number of studies have examined different aspects of the host response in gingival crevicular fluid (GCF), including the relationship of specific markers to the active phases of periodontal disease. Various indicators of the acute inflammatory response (the lysosomal enzymes P-glucuronidase and collagenase, the cytoplasmic enzyme aspartate aminotransferase, and the arachidonic acid metabolite PGE2) have been shown to be associated with clinical attachment loss in chronic adult periodontitis in man and experimental periodontitis in animal models. In contrast, the relationship of indicators of the humoral immune response in GCF to active periodontal disease is equivocal. Furthermore, a number of indicators of the cellular immune response have been identified recently in GCF (i.e., Interleukin-la, IL-1β, tumor necrosis factor-a), but their relationship to active phases of periodontal disease have not been studied. The polymorphonuclear leukocyte (PMN) is the cellular hallmark of acute inflammation. Evidence from the GCF studies suggests that hyperreactivity of these cells plays a critical role in the active phases of some forms of periodontal disease. Metabolic activation of PMN can be associated with a number of potentially destructive reactions. The major effector mechanism for tissue destruction that can be specifically identified with the PMN is the synergistic effect of the release of PMN proteases and the generation of reactive oxygen metabolites by these cells. Priming of the PMN, where the PMN response is enhanced by agents that do not initiate the response, may be an important mechanism for PMN activation in the crevicular environment; for example, cytokines such as IL-1β and TNF-a, and lipopolysaccharides released from subgingival Gram-negative bacteria, can serve this function. The hypothesis proposed here argues that in addition to the severe forms of periodontal disease that have been associated with qualitative or quantitative PMN defects, tissue destruction in the periodontum can be observed with hyperreactivity of these cells. These differing conclusions do not create a dilemma, but may represent opposite ends of a balance that is no longer in equilibrium.

Enhanced myocyte-based biosensing of the blood-borne signals regulating chronotropy

2002 ◽  
Vol 92 (2) ◽  
pp. 581-585 ◽  
Author(s):  
Jay M. Edelberg ◽  
Jason T. Jacobson ◽  
David S. Gidseg ◽  
Lilong Tang ◽  
David J. Christini
Keyword(s):  
Cardiac Myocyte ◽  
Cardiac Tissue ◽  
Critical Role ◽  
Excitable Tissue ◽  
Time Determination ◽  
Molecular Plasticity ◽  
Relationship Of ◽  
High Degree

Biosensors play a critical role in the real-time determination of relevant functional physiological needs. However, typical in vivo biosensors only approximate endogenous function via the measurement of surrogate signals and, therefore, may often lack a high degree of dynamic fidelity with physiological requirements. To overcome this limitation, we have developed an excitable tissue-based implantable biosensor approach, which exploits the inherent electropotential input-output relationship of cardiac myocytes to measure the physiological regulatory inputs of chronotropic demand via the detection of blood-borne signals. In this study, we report the improvement of this application through the modulation of host-biosensor communication via the enhancement of vascularization of chronotropic complexes in mice. Moreover, in an effort to further improve translational applicability as well as molecular plasticity, we have advanced this approach by employing stem cell-derived cardiac myocyte aggregates in place of whole cardiac tissue. Overall, these studies demonstrate the potential of biologically based biosensors to predict endogenous physiological dynamics and may facilitate the translation of this approach for in vivo monitoring.

scholarly journals Genome-wide analysis of the aquaporin genes in melon (Cucumis melo L.)

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Alvaro Lopez-Zaplana ◽  
Juan Nicolas-Espinosa ◽  
Micaela Carvajal ◽  
Gloria Bárzana
Keyword(s):  
Cucumis Melo ◽  
Evolutionary Relationship ◽  
Physiological Importance ◽  
Genome Wide ◽  
Related Plant ◽  
Complete Set ◽  
The Individual ◽  
Almost All ◽  
Relationship Of ◽  
Cucumis Melo L

AbstractMelon (Cucumis melo L.) is a very important crop throughout the world and has great economic importance, in part due to its nutritional properties. It prefers well-drained soil with low acidity and has a strong demand for water during fruit set. Therefore, a correct water balance—involving aquaporins—is necessary to maintain the plants in optimal condition. This manuscript describes the identification and comparative analysis of the complete set of aquaporins in melon. 31 aquaporin genes were identified, classified and analysed according to the evolutionary relationship of melon with related plant species. The individual role of each aquaporin in the transport of water, ions and small molecules was discussed. Finally, qPCR revealed that almost all melon aquaporins in roots and leaves were constitutively expressed. However, the high variations in expression among them point to different roles in water and solute transport, providing important features as that CmPIP1;1 is the predominant isoform and CmTIP1;1 is revealed as the most important osmoregulator in the tonoplast under optimal conditions. The results of this work pointing to the physiological importance of each individual aquaporin of melon opening a field of knowledge that deserves to be investigated.

scholarly journals Anthropocene Crisis: Climate Change, Pollinators, and Food Security

Environments ◽  
2019 ◽  
Vol 6 (2) ◽  
pp. 22 ◽  
Author(s):  
Jennifer Marshman ◽  
Alison Blay-Palmer ◽  
Karen Landman
Keyword(s):  
Critical Role ◽  
Natural World ◽  
Direct Result ◽  
Geological Time ◽  
Geological Time Scale ◽  
Habitat Creation ◽  
Community Approach ◽  
Relationship Of ◽  
Institutional Space

In this paper, we propose a new approach—understood as a whole-of-community approach—to address a dualistic and dysfunctional human/nature relationship. Of particular concern is the decline in health and numbers of the insects that pollinate an estimated 90 percent of the Earth’s flora and an estimated 35 percent of global crop volume. Specifically, bees provide the majority of biotic pollination and play a critical role in food crop pollination. Multiple factors are contributing to this growing problem including a changing climate. In 2016, the International Commission on Stratigraphy agreed that the concept of the Anthropocene—the human epoch—is of sufficient scale to be considered part of the geological time scale. This indicates that these crises are not random or passive—they are largely the direct result of human activities. Despite decades of awareness of these socio-ecological issues, they continue to worsen. In addition, the growing awareness of the critical role of pollinators is creating a new understanding of our interconnectedness with the “natural” world. We introduce the Bee City movement as a way to operationalize a whole-of-community approach. Individual action is critical, but addressing pollinator health in these forums legitimizes and provides an institutional space for otherwise fringe, or even marginalized, activities and more coherent spaces for habitat creation.

The Role of Unabsorbed Slack in Internal and Collaborative Innovation Processes — A Resource-Based Framework

2016 ◽  
Vol 13 (03) ◽  
pp. 1640007 ◽  
Author(s):  
Ulrich Lichtenthaler
Keyword(s):  
Critical Role ◽  
Slack Resources ◽  
Fine Grained ◽  
Collaborative Innovation ◽  
Relationship Of ◽  
The Impact ◽  
The Relationship ◽  
Unabsorbed Slack ◽  
Innovation Processes

Extant research has highlighted the critical role of unabsorbed slack resources in internal innovation processes. In recent years, many firms have continued to open up their innovation processes to actively collaborate with external partners. In light of a limited understanding of the determinants of collaborative innovation, we provide new theoretical arguments about the relationship of unabsorbed slack resources with internal and collaborative innovation processes. Specifically, we draw on resource-based and competence-based logic and develop a conceptual framework for intraorganizational and interorganizational innovation with propositions for the impact of unabsorbed slack resources on internal and external knowledge acquisition and commercialization processes. The arguments underscore the critical role of excess resources in collaborative innovation, and they highlight the need for a fine-grained examination of the impact of unabsorbed slack resources in innovation processes. The arguments are particularly important in light of a renewed interest in essential enablers and barriers to collaborative innovation processes.

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