Active Processes in Insect Hearing

Author(s):  
Martin C. Göpfert ◽  
Daniel Robert
1972 ◽  
Vol 50 (1) ◽  
pp. 37-44 ◽  
Author(s):  
E. C. Vos ◽  
G. B. Frank

A brief exposure (about 10–30 s) of a frog's toe muscle or a small bundle of fibers from the semi-tendinosus muscle to just subthreshold potassium concentrations potentiated contractures subsequently produced by exposing the muscles to a potassium concentration slightly above the threshold. The contractures thus potentiated had greater maximum tensions, and greater rates of tension development and relaxation than control contractures elicited by the same final potassium concentration. The resistance to stretch (R.T.S.) in the first few seconds of the potentiated contractures was about twice that of control contractures. Maximum potentiation occurred with preexposures of about 30 s; longer preexposures led to a decrease of potentiation and eventually to a depression of the contracture. The potentiation was not immediately abolished when the muscle was reexposed to Ringer solution but persisted for 2 min or longer (the 'washout effect'). It was concluded that exposing a muscle to low subcontracture threshold concentrations of potassium for a few seconds primes the intracellular contractile apparatus, probably by causing an increased sarcoplasmic concentration of Ca2+ ions, resulting in a potentiation of subsequently induced submaximal potassium contractures. The increase in metabolism (or 'Solandt effect') seen under these conditions is temporally related to the decline and eventual loss of the potentiation and is probably a reflection of active processes involved in reducing the sarcoplasmic concentration of Ca2+ ions.


Solid Earth ◽  
2017 ◽  
Vol 8 (5) ◽  
pp. 921-941 ◽  
Author(s):  
Mauro Cacace ◽  
Antoine B. Jacquey

Abstract. Theory and numerical implementation describing groundwater flow and the transport of heat and solute mass in fully saturated fractured rocks with elasto-plastic mechanical feedbacks are developed. In our formulation, fractures are considered as being of lower dimension than the hosting deformable porous rock and we consider their hydraulic and mechanical apertures as scaling parameters to ensure continuous exchange of fluid mass and energy within the fracture–solid matrix system. The coupled system of equations is implemented in a new simulator code that makes use of a Galerkin finite-element technique. The code builds on a flexible, object-oriented numerical framework (MOOSE, Multiphysics Object Oriented Simulation Environment) which provides an extensive scalable parallel and implicit coupling to solve for the multiphysics problem. The governing equations of groundwater flow, heat and mass transport, and rock deformation are solved in a weak sense (either by classical Newton–Raphson or by free Jacobian inexact Newton–Krylow schemes) on an underlying unstructured mesh. Nonlinear feedbacks among the active processes are enforced by considering evolving fluid and rock properties depending on the thermo-hydro-mechanical state of the system and the local structure, i.e. degree of connectivity, of the fracture system. A suite of applications is presented to illustrate the flexibility and capability of the new simulator to address problems of increasing complexity and occurring at different spatial (from centimetres to tens of kilometres) and temporal scales (from minutes to hundreds of years).


2019 ◽  
Vol 407 ◽  
pp. 121-147 ◽  
Author(s):  
A. Rodríguez-Zurrunero ◽  
J.L. Granja-Bruña ◽  
A. Carbó-Gorosabel ◽  
A. Muñoz-Martín ◽  
J.M. Gorosabel-Araus ◽  
...  

2010 ◽  
Vol 7 (3) ◽  
pp. 3329-3363 ◽  
Author(s):  
G. A. Ali ◽  
A. G. Roy

Abstract. While a large number of non-linear hillslope and catchment rainfall-runoff responses have been attributed to the temporal variability in antecedent moisture conditions (AMCs), two problems emerge: 1) the difficulty of measuring AMCs, and 2) the absence of explicit guidelines for the choice of surrogates or proxies for AMCs. This paper aims at determining whether or not multiple surrogates for AMCs should be used in order not to bias our understanding of a system hydrological behaviour. We worked in a small forested catchment, the Hermine, where soil moisture has been measured at 121 different locations at four depths on 16 occasions. Without making any assumption on active processes, we used various linear and nonlinear regression models to evaluate the point-scale temporal relations between actual soil moisture contents and selected meteorological-based surrogates for AMCs. We then mapped the nature of the "best fit" model to identify 1) spatial clusters of soil moisture monitoring sites whose hydrological behaviour was similar, and 2) potential topographic influences on these behaviours. Two conclusions stood out. Firstly, it was shown that the sole reference to AMCs indices traditionally used in catchment hydrology, namely antecedent rainfall amounts summed over periods of seven or ten days, would have led to an incomplete understanding of the Hermine catchment dynamics. Secondly, the relationships between point-scale soil moisture content and surrogates for AMCs were not spatially homogeneous, thus revealing a mosaic of linear and nonlinear catchment "active" and "contributing" sources whose location was often controlled by surface terrain attributes or the topography of a soil-confining layer interface. These results represent a step forward in developing a hydrological conceptual model for the Hermine catchment as they indicate depth-specific processes and spatially-variable triggering conditions. Further investigations are, however, necessary in order to derive general guidelines for the choice of the best surrogates for AMCs in a catchment.


2019 ◽  
Vol 4 (2) ◽  
pp. 410-433 ◽  
Author(s):  
Teoma Naccarato ◽  
John MacCallum

This paper is a invitation to interaction designers across disciplines to rethink the shaping of interaction “intra-actively”. Whether in human-computer interaction design or interdisciplinary and interactive performance practices, we propose to shift the emphasis from interaction between things, towards the intra-active processes of differentiation by which such things are continually made and unmade. Expanding interaction design by engaging in processes intended to bring awareness to the value systems involved in the local production of “interaction” and “things that interact” offers an opportunity to treat these values, and likewise the designers (be it engineers or choreographers or composers), as objects themselves in the design process. In the traditions of feminist, new materialist, and process philosophy we weave a narrative of appropriated perspectives in order to dismantle hegemonic accounts of correlationism and representationalism in interaction design, while investigating the concepts of boundary objects, diffraction, and critical appropriation as potential approaches to intra-active design.


2020 ◽  
Vol 73 (11) ◽  
pp. 2339-2344
Author(s):  
Igor S. Brodetskyi ◽  
Olena O. Dyadyk ◽  
Mykhailo S. Myroshnychenko ◽  
Valentina I. Zaritska

The aim of the study is to reveal the morphological features of pleomorphic adenomas of the salivary glands during a comprehensive examination of the surgical material. Materials and methods: Surgical material from 30 patients with pleomorphic adenomas of the salivary glands was studied. Microspecimens stained with hematoxylin and eosin were studied, using an Olympus BX-41 microscope (Japan) with subsequent processing with the Olympus DP-soft version 3.1 software, which was used to conduct a morphometric study. By morphometry in the tumor tissue, the specific volumes of the parenchyma and stroma, the thickness of the capsule located between the tumor tissue and the tissue of the salivary gland were determined; the absolute number of vessels in the field of view of the microscope was counted at × 100 magnification. Results: Comprehensive morphological analysis of the surgical material of removed neoplasms of the salivary glands has showed that mesenchymal (15 cases, 50.0%) and mixed (10 cases, 33.3%) variants of pleomorphic adenomas are more common, and less often epithelial variants (5 cases, 16.7%). Pleomorphic adenoma is characterized by a different ratio of the epithelial (parenchymal) and mesenchymal (stromal) components forming this tumor, structural diversity and heterogeneity of the structure of these components, which do not have clear boundaries and are mixed with each other. A characteristic feature of pleomorphic adenoma is also the combination in each case of different types of epithelial cells and the structures that they form, as well as areas of various differentiation of the mesenchymal component. Mesenchymal and mixed variants of pleomorphic adenomas, in comparison with the epithelial variant, are more prone to progression and recurrence, as evidenced by our identified active processes of angiogenesis in tumor tissue, frequent tumor invasion of the capsule, thinning of the capsule or the absence of the capsule, less pronounced infiltration of the capsule by immune cells. Conclusions: The morphological features of mesenchymal, mixed and epithelial variants of pleomorphic adenomas of the salivary glands revealed by the authors should be taken into account by clinicians during choosing the tactics for treating the patient, which will undoubtedly help to reduce the incidence of tumor malignization and its recurrence.


2021 ◽  
pp. 6-12
Author(s):  
А.И. Ольховская

Статья преследует цель дополнения и расширения словарной типологии В.В. Морковкина с учетом активных процессов в современной лексикографии. В ней рассматриваются словари, появившиеся за последние 30 лет, и предпринимается попытка органично вписать их в намеченную ученым модель лексикографического пространства. Автор вводит четвертое измерение классификации («кто»-основание) и предлагает ряд новых параметров для оценки словарных продуктов (природа рассматриваемого в словаре объекта, метаязык словарного описания, стиль подачи информации, носитель информации, исходные материалы и др.). Обсуждаемые в статье противопоставления словарей (бумажные – электронные, картотечные – корпусные, вербальные – поликодовые, авторские – волонтерские – партнерские и мн. др.) развивают идеи В.В. Морковкина и способствуют их актуализации. The article aims to supplement and expand the dictionary typology of V.V. Morkovkin, taking into account the active processes in the modern lexicography. There considered dictionaries appeared over the past 30 years, and attempted to organically fit them into the model of lexicographic space planned by the scientist. The author introduces the fourth dimension of classification (“who”-the basis) and offers several new parameters for evaluating dictionary products (the nature of the object considered in the dictionary, the metalanguage of the dictionary description, the style of information presentation, the information carrier, source materials, etc.). The contrasts of dictionaries discussed in the article (paper – electronic, card – case, verbal – polycode, author's – volunteer – partner, etc.) develop ideas of V.V. Morkovkin and contribute to their actualization.


2021 ◽  
pp. 9-24
Author(s):  
A. A. Arsenyev ◽  
D. S. Leontiev ◽  
M. D. Zavatsky ◽  
V. V. Saltykov

This article analyzes the prospects of petroleum potential in Kurgan region. The relevance of the work is due to the high degree of development of the traditional oil and gas recovery areas of Western Siberia, which leads to the need to organize search activities in areas with a low density of hydrocarbon resources. We have analyzed the results of exploratory drilling in the area of the Alabuga river in Kurgan region, and have studied the history of detections of onshore oil occurrences there. Based on the results of the retrospective analysis, the research area was determined, field work was performed to determine the state of search wells in the area, and a collection of geochemical soil and liquid samples was selected. The analysis of the samples revealed that all of them contain methane and its homologues up to and including pentane. The genesis of light methane homologs is related to the processes of catagenesis; their detection on the surface indicates active processes of generation and migration of petroleum hydrocarbons. Based on the analysis of archival materials and estimated ground-based geochemical studies, a conclusion is made about petroleum potential in Kurgan region.


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