Instrumentation and Measurement of Ground-Level Ultraviolet Irradiance and Spectral Composition in Estonia

It is now well-known that chatter (Figure 1) is caused by vibration between the microtome arm and the diamond knife. It is usually observed as a cyclical variation in “optical” density of an electron micrograph due to sample thickness variations perpendicular to the cutting direction. This vibration might be induced by using too large a block face, too large a clearance angle, excessive cutting speed, non-uniform embedding medium or microtome vibration. Another prominent cause is environmental vibration caused by inadequate building construction. Microtomes should be installed on firm, solid floors. The best floors are thick, ground-level concrete pads poured over a sand bed and isolated from the building walls. Even when these precautions are followed, we recommend an additional isolation pad placed on the top of a sturdy table.

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Amplitude Distributions of Cochlear Microphonic Response to an Acoustic Sinusoid in Noise

Journal of Speech and Hearing Research ◽

10.1044/jshr.1101.63 ◽

1968 ◽

Vol 11 (1) ◽

pp. 63-76

Author(s):

Donald C. Teas ◽

Gretchen B. Henry

Keyword(s):

Small Amplitude ◽

Basilar Membrane ◽

Spectral Composition ◽

Pass Band ◽

Cochlear Microphonic ◽

Filter Output ◽

Electronic Filter ◽

Low Pass ◽

Band Pass ◽

Instantaneous Voltage

The distributions of instantaneous voltage amplitudes in the cochlear microphonic response recorded from a small segment along the basilar membrane are described by computing amplitude histograms. Comparisons are made between the distributions for noise and for those after the addition to the noise of successively stronger sinusoids. The amplitudes of the cochlear microphonic response to 5000 Hz low-pass noise are normally distributed in both Turn I and Turn III of the guinea pig’s cochlea. The spectral composition of the microphonic from Turn I and from Turn III resembles the output of band-pass filters set at about 4000 Hz, and about 500 Hz, respectively. The normal distribution of cochlear microphonic amplitudes for noise is systematically altered by increasing the strength of the added sinusoid. A decrease of three percent in the number of small amplitude events (±1 standard deviation) in the cochlear microphonic from Turn III is seen when the rms voltage of a 500 Hz sinusoid is at −18 dB re the rms voltage of the noise (at the earphone). When the rms of the sinusoid and noise are equal, the decrease in small voltages is about 25%, but there is also an increase in the number of large voltage amplitudes. Histograms were also computed for the output of an electronic filter with a pass-band similar to Turn III of the cochlea. Strong 500 Hz sinusoids showed a greater proportion of large amplitudes in the filter output than in CM III . The data are interpreted in terms of an anatomical substrate.

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A global perspective of ground level, 'ambient' carbon dioxide for assessing the response of plants to atmospheric CO2

Global Change Biology ◽

10.1046/j.1365-2486.2001.00436.x ◽

2001 ◽

Vol 7 (7) ◽

pp. 789-796 ◽

Cited By ~ 23

Author(s):

L. H. Ziska ◽

O. Ghannoum ◽

J. T. Baker ◽

J. Conroy ◽

J. A. Bunce ◽

...

Keyword(s):

Carbon Dioxide ◽

Ground Level ◽

Global Perspective ◽

Atmospheric Co2

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New observations show ground-level ozone is increasing Northern Hemisphere

AccessScience ◽

10.1036/1097-8542.br0825201 ◽

2020 ◽

Keyword(s):

Northern Hemisphere ◽

Ground Level ◽

Ground Level Ozone

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Ground-level ozone on the rise

Nature ◽

10.1038/news.2008.1153 ◽

2008 ◽

Author(s):

Natasha Gilbert

Keyword(s):

Ground Level ◽

Ground Level Ozone

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The Sovereign States of Vietnam, 1945–1955

Journal of Vietnamese Studies ◽

10.1525/jvs.2016.11.3-4.103 ◽

2016 ◽

Vol 11 (3-4) ◽

pp. 103-139 ◽

Cited By ~ 1

Author(s):

Brett Reilly

Keyword(s):

Ground Level ◽

Indochina War

This paper revisits the “bricolage” State of Vietnam and the fractured system of sovereignty that characterized its halting practice of sovereignty at the ground level during the First Indochina War. In addition, it examines how the French Union’s concept of shared external sovereignty became discredited by the end of the war.

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