Does breathing disturb arm to leg coordination in butterfly

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Hydrologic Properties of Subarctic Organic Soils

Completion Report for U. S. Forest Service Institute of Northern Forestry Cooperative Agreement No. 16 USC 581; 581a-581iThe need for understanding the natural system and how it responds to various stresses is important; this is especially so in an environment where the climate not only sustains permafrost, but develops massive seasonal frost as well. Consequently, the role of the shallow surface organic layer is also quite important. Since a slight change in the soil thermal regime may bring about a phase change in the water or ice, therefore, the system response to surface alterations such as burning can be quite severe. The need for a better understanding of the behavior and properties of the organic layer is, therefore, accentuated. The central theme of this study was the examination of the hydrologic and hydraulic properties of subarctic organic soils. Summarized in this paper are the results of three aspects of subarctic organic soil examinations conducted during the duration of the project. First, a field site was set up in Washington Creek with the major emphasis on measuring numerous variables of that soil system during the summer. The greatest variations in moisture content occur in the thick organic soils that exist at this site. Our major emphasis was to study the soil moisture levels in these soils. This topic is covered in the first major section, including associated laboratory studies. Those laboratory studies include investigations of several hydraulic and hydrologic properties of taiga organic and mineral soils. Second, some field data on organic moisture levels was collected at the site of prescribed burns in Washington Creek to ascertain the sustainability of fires as a function of moisture levels. This portion of the study is described under the second major heading. The last element of this study was a continued application of the two-dimensional flow model that was developed in an earlier study funded by the U. S. Forest Service, Institute of Northern Forestry, and reported by Kane, Luthin, and Taylor (1975a). Many of the results and concepts gathered in the field work were integrated into the modeling effort, which is aimed at producing better estimates of the hydrologic effects of surface disturbances in the black spruce taiga subarctic ecosystem. This knowledge should also contribute to better fire management decisions of the same system.The work upon which this report is based was made possible by a cooperative aid agreement funded by the U. S. Forest Service, Institute of Northern Forestry, Fairbanks, Alaska. Contribution to this study was also made by Ohio State University

Non-linear properties of supercooled liquids in the system Na2O---SiO2

The physical properties, viscosity, density, heat capacity and thermal expansivity, of relaxed supercooled liquids in the temperature range just above the glass transition have been determined for ten compositions along the compositional binary Na2O---SiO2, in the range of 2–45 mole% Na2O, by a combination of scanning calorimetry, dilatometry and micropenetration viscometry. The viscosity, density, heat capacity and thermal expansivity in the glassy state have also been determined. The heat capacities illustrate a linear composition dependence for the glassy state and a smooth but strongly non-linear composition dependence for the supercooled liquid state. The thermal expansivities were determined by dilatometry up to the glass transition and, by a normalized comparison of relaxation behavior in the glass transition interval, to temperatures 50°C above the glass transition. The expansivity is a linear function of the molar composition in the glass but a strongly non-linear function of molar composition in the supercooled liquid. The viscosity data just above the glass transition temperature, combined with data from high temperature using the concentric cylinder method, illustrate that the composition dependence of viscosity is strongly non-linear and exhibits an inflection as a function of composition. The glass transition temperature, taken as the peak temperature of the calorimetric measurements, is not in general an isokom in this system. The data for these property determinations in the Na2O---SiO2 system provide much improved constraints on the partial molar properties of SiO2 liquid and partial molar properties of the SiO2 component in silicate melts. The complex behavior of the transport properties, i.e. the glass transition temperature and the viscosity, point to complexities in viscous flow beyond that of simple binary mixing of the Na2O and SiO2 components

Efficiency of autonomous soft nano-machines at maximum power

We consider nano-sized artificial or biological machines working in steady state enforced by imposing non-equilibrium concentrations of solutes or by applying external forces, torques or electric fields. For unicyclic and strongly coupled multicyclic machines, efficiency at maximum power is not bounded by the linear response value 1/2. For strong driving, it can even approach the thermodynamic limit 1. Quite generally, such machines fall in three different classes characterized, respectively, as "strong and efficient", "strong and inefficient", and "balanced". For weakly coupled multicyclic machines, efficiency at maximum power has lost any universality even in the linear response regime

Tubular structures of GaS

In this Brief Report we demonstrate, using density-functional tight-binding theory, that gallium sulfide (GaS) tubular nanostructures are stable and energetically viable. The GaS-based nanotubes have a semiconducting direct gap which grows towards the value of two-dimensional hexagonal GaS sheet and is in contrast to carbon nanotubes largely independent of chirality. We further report on the mechanical properties of the GaS-based nanotubes

Can the Tajmar effect be explained using a modification of inertia?

The Tajmar effect is an unexplained acceleration observed by accelerometers and laser gyroscopes close to rotating supercooled rings. The observed ratio between the gyroscope and ring accelerations was 3+/-1.2x10^-8. Here, a new model for inertia which has been tested quite successfully on the Pioneer and flyby anomalies is applied to this problem. The model assumes that the inertia of the gyroscope is caused by Unruh radiation that appears as the ring and the fixed stars accelerate relative to it, and that this radiation is subject to a Hubble-scale Casimir effect. The model predicts that the sudden acceleration of the nearby ring causes a slight increase in the inertial mass of the gyroscope, and, to conserve momentum in the reference frame of the spinning Earth, the gyroscope rotates clockwise with an acceleration ratio of 1.8+/-0.25x10^-8 in agreement with the observed ratio. However, this model does not explain the parity violation seen in some of the gyroscope data. To test these ideas the Tajmar experiment (setup B) could be exactly reproduced in the southern hemisphere, since the model predicts that the anomalous acceleration should then be anticlockwise.Comment: 9 pages, 1 figure. Accepted by EPL on the 4th December, 200

Metabolic reprogramming of murine cardiomyocytes during autophagy requires the extracellular nutrient sensor decorin.

The extracellular matrix is a master regulator of tissue homeostasis in health and disease. Here we examined how the small, leucine-rich, extracellular matrix proteoglycan decorin regulates cardiomyocyte metabolism during fasting in vivo. First, we validated in Dcn-/- mice that decorin plays an essential role in autophagy induced by fasting. High-Throughput metabolomics analyses of cardiac tissue in Dcn-/- mice subjected to fasting revealed striking differences in the hexosamine biosynthetic pathway resulting in aberrant cardiac O-β-N-Acetylglycosylation as compared with WT mice. Functionally, Dcn-/- mice maintained cardiac function at a level comparable with nonfasted animals whereas fasted WT mice showed reduced ejection fraction. Collectively, our results suggest that reduced sensing of nutrient deprivation in the absence of decorin preempts functional adjustments of cardiac output associated with metabolic reprogramming. © 2018 Gubbiotti et al