Assessing the Impacts of Commercial Clearcut on Freshwater Invertebrate Communities

Forest harvesting can impact the environment in many ways, one of which is causing a loss of subsidies and increased light intensity to freshwater ecosystems. This can have a major impact on freshwater invertebrate communities that may rely on subsidies to survive. In this study, I tested two effects of commercial clearcut, changes in light availability and detrital resources, on freshwater invertebrate communities. Cattle tanks containing freshwater invertebrates were given detritus from two different plots: one which underwent commercial clearcut over 50 years ago, and one which underwent commercial clearcut 2 years ago. Tanks were also placed in two areas of differing canopy: one shaded, another open. The abundance, richness, and composition of the invertebrate communities were measured. There was no significant difference between the 50-year and 2-year clearcut leaf subsidy treatments, but there was a significant difference between the shaded and opened canopy treatment. This indicates that a lack of canopy over a freshwater ecosystem in autumn or winter alters freshwater invertebrate communities through light availability rather than through a lack of detritus

Two-Camera Acquisition and Tracking of a Flying Target

A method and apparatus have been developed to solve the problem of automated acquisition and tracking, from a location on the ground, of a luminous moving target in the sky. The method involves the use of two electronic cameras: (1) a stationary camera having a wide field of view, positioned and oriented to image the entire sky; and (2) a camera that has a much narrower field of view (a few degrees wide) and is mounted on a two-axis gimbal. The wide-field-of-view stationary camera is used to initially identify the target against the background sky. So that the approximate position of the target can be determined, pixel locations on the image-detector plane in the stationary camera are calibrated with respect to azimuth and elevation. The approximate target position is used to initially aim the gimballed narrow-field-of-view camera in the approximate direction of the target. Next, the narrow-field-of view camera locks onto the target image, and thereafter the gimbals are actuated as needed to maintain lock and thereby track the target with precision greater than that attainable by use of the stationary camera

Low-frequency internal friction in clamped-free thin wires

We present a series of internal friction measurements for the normal modes of circular fibres made of different materials, that can suspend the test masses of an interferometric gravity wave detector. For metallic wires, the frequency independent loss angle ranges between 10 y3 and 10 y4 . The losses in fused silica are two orders of magnitude lower than those in metals

Final Results from phase II of the Mainz Neutrino Mass Search in Tritium β\beta Decay

The paper reports on the improved Mainz experiment on tritum $\beta$ spectroscopy which yields a 10 times' higher signal to background ratio than before. The main experimental effects and systematic uncertainties have been investigated in side experiments and possible error sources have been eliminated. Extensive data taking took place in the years 1997 to 2001. A residual analysis of the data sets yields for the square of the electron antineutrino mass the final result of $m^2(\nu_e)=(-0.6 \pm 2.2_{\rm{stat}} \pm 2.1_{\rm{syst}})$ eV$^2$/c$^4$. We derive an upper limit of $m(\nu_e)\leq 2.3$ eV/c$^2$ at 95% confidence level for the mass itself.Comment: 22 pages, 22 figures submitted to EPJ

MECHANICAL SHOT NOISE INDUCED BY CREEP IN SUSPENSION DEVICES

Abstract The sensitivity curve of a gravitational wave interferometric detector like VIRGO might be seriously limited by the mechanical shot noise induced by stationary creep in the heavily loaded mechanical suspension components (wires, spring blades, etc.). We quantify this effect and discuss possible improvements which could be implemented without major design alterations

Crystal Structure and Magnetocaloric Effect of La0.80Ag0.15MnO3 Nanoparticles

Annealing of_ non stoichiometric La0.80Ag0.15MnO3 nanoparticles leads to the change of the crystal symmetry from Pnma to R3c and to almost doubling of its Curie temperature from 117 K to 317 K. This effect is due to the releasing of lattice distortions and strengthening of double exchange interaction. The large values of the magnetocaloric entropy of the order of ∆S = 6.19 J/(kg K) were observedat ∆µ0H = 5 T and T = 315 K.Proceedings of the 17th Czech and Slovak Conference on Magnetism, Košice, Slovakia, June 3–7, 2019

Fasting increases susceptibility to acute myocardial ischaemia/reperfusion injury through a sirtuin-3 mediated increase in fatty acid oxidation.

Fasting increases susceptibility to acute myocardial ischaemia/reperfusion injury (IRI) but the mechanisms are unknown. Here, we investigate the role of the mitochondrial NAD+-dependent deacetylase, Sirtuin-3 (SIRT3), which has been shown to influence fatty acid oxidation and cardiac outcomes, as a potential mediator of this effect. Fasting was shown to shift metabolism from glucose towards fatty acid oxidation. This change in metabolic fuel substrate utilisation increased myocardial infarct size in wild-type (WT), but not SIRT3 heterozygous knock-out (KO) mice. Further analysis revealed SIRT3 KO mice were better adapted to starvation through an improved cardiac efficiency, thus protecting them from acute myocardial IRI. Mitochondria from SIRT3 KO mice were hyperacetylated compared to WT mice which may regulate key metabolic processes controlling glucose and fatty acid utilisation in the heart. Fasting and the associated metabolic switch to fatty acid respiration worsens outcomes in WT hearts, whilst hearts from SIRT3 KO mice are better adapted to oxidising fatty acids, thereby protecting them from acute myocardial IRI