A Laboratory System for Maintaining Small-Volume Cultures of Foraminifera and Other Organisms

1966 ◽  
Vol 12 (1) ◽  
pp. 109 ◽  
Author(s):  
Zach M. Arnold
Keyword(s):  
Small Volume ◽  
Laboratory System

Bakerian Lecture: The acceleration of protons to energies above 10 GeV

1956 ◽  
Vol 234 (1199) ◽  
pp. 441-456 ◽  
Keyword(s):  
Small Volume ◽  
Nucleon Nucleon ◽  
Laboratory System ◽  
Centre Of Mass ◽  
Positron Energy ◽  
High Energies ◽  
Modern Physics ◽  
The Creation ◽  
Stable Particles ◽  
Very High

The various projects now under way to produce in the laboratory beams of protons and other elementary particles with very high energies, are often criticized as a very expensive extreme of fashion in modern physics. It is true that there has been uneconomic and unnecessary duplication of many kinds of accelerators, and that some which have been built are not being used to full advantage. However, attempts to reach in the laboratory particle energies of at least 10 GeV are essential if the frontiers of physics are to be extended. The study of the physics of particles is much concerned with the creation of both short-lived and stable particles in collisions between nucleons. In a collision between a relativistic nucleon and one which is at rest, a great concentration of energy is produced in a very small volume. This energy may be utilized, in part, to give material existence to those particles whose virtual existence is postulated by modern field theory as responsible for the nucleon interactions. Such particles are in general created in pairs—the particle and its anti-particle—as is well known in the case of the electron and its anti-particle, the positron. Energy of at least 2m 0 c 2 must be ‘compressed’ into a volume of the order of nucleon dimensions in order to create a pair of nucleons. This concentrated energy is the energy in the system moving with the centre of mass of the colliding particles, and not the energy in the laboratory system. Figure 1 shows how the energy available for the creation of pairs of particles in nucleon-nucleon collisions varies with the kinetic energy of the bombarding nucleons. Internal momentum, due to a possible structure of the nucleons, may modify these values a little, but according to Heisenberg by not more than 0⋅5 GeV.

Protamine-DNA interaction

1978 ◽  
Vol 36 (2) ◽  
pp. 200-201
Author(s):  
D.P. Bazett-Jones ◽  
F.P. Ottensmeyer
Keyword(s):  
Small Volume ◽  
Double Helix ◽  
Dna Interaction ◽  
Dark Field ◽  
Sperm Head ◽  
Nuclear Proteins ◽  
Field Electron Microscopy ◽  
Dark Field Electron ◽  
Dna Double Helix ◽  
Positively Charged

Dark field electron microscopy has been used for the study of the structure of individual macromolecules with a resolution to at least the 5Å level. The use of this technique has been extended to the investigation of structure of interacting molecules, particularly the interaction between DNA and fish protamine, a class of basic nuclear proteins of molecular weight 4,000 daltons.Protamine, which is synthesized during spermatogenesis, binds to chromatin, displaces the somatic histones and wraps up the DNA to fit into the small volume of the sperm head. It has been proposed that protamine, existing as an extended polypeptide, winds around the minor groove of the DNA double helix, with protamine's positively-charged arginines lining up with the negatively-charged phosphates of DNA. However, viewing protamine as an extended protein is inconsistent with the results obtained in our laboratory.

The Theoretical Contrast in Scanning and Conventional High Resolution Microscopes

1969 ◽  
Vol 27 ◽  
pp. 170-171
Author(s):  
E. Zeitler ◽  
M. G. R. Thomson
Keyword(s):  
Small Volume ◽  
Volume Element ◽  
Optical Processing ◽  
Image Construction ◽  
Object Interaction ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Optical Treatment ◽  
Electron Microscopes ◽  
Intensity Contrast

In the formation of an image each small volume element of the object is correlated to an areal element in the image. The structure or detail of the object is represented by changes in intensity from element to element, and this variation of intensity (contrast) is determined by the interaction of the electrons with the specimen, and by the optical processing of the information-carrying electrons. Both conventional and scanning transmission electron microscopes form images which may be considered in this way, but the mechanism of image construction is very different in the two cases. Although the electron-object interaction is the same, the optical treatment differs.

Planning Micronutrient-Dense Menus in Ontario Long-Term Care Homes: Strategies and Challenges

2020 ◽  
Vol 81 (4) ◽  
pp. 198-203
Author(s):  
Lisa M. Duizer ◽  
Heather H. Keller
Keyword(s):  
Small Volume ◽  
Long Term Care ◽  
Term Care ◽  
Dietary Reference Intakes ◽  
Portion Sizes ◽  
Calcium Magnesium ◽  
Micronutrient Malnutrition ◽  
Low Levels ◽  
Food Consumed

Prevalence of micronutrient malnutrition is high in individuals living in long-term care (LTC) homes with many individuals consuming low levels of vitamins B6, D, and E; folate; calcium; magnesium; and zinc. The focus of this research was to identify strategies and challenges encountered during development of micronutrient-dense menus for use in Ontario LTC homes and to examine costs associated with development of a menu with acceptable micronutrients. Semi-structured open-ended interviews were conducted with 13 menu planners (7 dietitians, 6 nutrition managers) in diverse LTC homes in Ontario. Data were thematically analyzed. A 7-day hypothetical menu meeting all nutrient requirements was developed and costed. Analysis of the interview data showed that menus are planned according to the Canada’s Food Guide (2007) and focus placed on Dietary Reference Intakes of protein, fibre, calcium, and sodium. Little focus is placed on micronutrients. Flexibility in foods offered was important to accommodate the small volume of food consumed. Resident preferences were balanced against nutritional requirements. Challenges included planning for diverse populations, managing portion sizes, and balancing the budget. A hypothetical menu planned to contain adequate levels of all micronutrients is 49% higher in food costs than the amount currently provided to Ontario LTC homes.

Flexible and Wearable GRF and EMG Sensors Enabled Locomotion Mode Recognition for IoHT Based In-home Rehabilitation

2020 ◽  
Author(s):  
Chaoming Fang ◽  
Yixuan Wang ◽  
Shuo Gao
Keyword(s):  
Sensitive Element ◽  
Small Volume ◽  
Peak Stress ◽  
Higher Learning ◽  
Force Sensing ◽  
Sensing System ◽  
Mode Recognition ◽  
Locomotion Mode ◽  
Stress Sensing ◽  
Manipulation Process

In order to quantify the manipulation process of acupuncture, in this article, a piezoelectric glove based wearable stress sensing system is presented. Served as the sensitive element with small volume and high tensile resistance, PVDF greatly meet the need of quantitative analysis. Through piezoelectric force sensing glove, the system is capable of detecting both perpendicular stress as well as shear stress. Besides, key parameters including peak stress at needle are detected and extracted, potentially allowing for a higher learning efficiency hence advancing the development of acupuncture.

Density Wave Measurements in a Rectangular Clarifier

1983 ◽  
Vol 18 (1) ◽  
pp. 129-150 ◽  
Author(s):  
Mark K. Watson ◽  
R.R. Hudgins ◽  
P.L. Silveston
Keyword(s):  
Power Spectrum ◽  
Internal Wave ◽  
Internal Waves ◽  
Wave Motion ◽  
Wave Amplitude ◽  
Suspended Solids ◽  
Small Volume ◽  
Density Wave ◽  
Measure Concentration ◽  
Wave Measurements

Abstract Internal wave motion was studied in a laboratory rectangular, primary clarifier. A photo-extinction device was used as a turbidimeter to measure concentration fluctuations in a small volume within the clarifier as a function of time. The signal from this device was fed to a HP21MX minicomputer and the power spectrum plotted from data records lasting approximately 30 min. Results show large changes of wave amplitude as frequency increases. Two distinct regions occur: one with high amplitudes at frequencies below 0.03 Hz, the second with very small amplitudes appears for frequencies greater than 0.1 Hz. The former is associated with internal waves, the latter with flow-generated turbulence. Depth, velocity in the clarifier and inlet suspended solids influence wave amplitudes and the spectra. A variation with position or orientation of the probe was not detected. Contradictory results were found for the influence of flow contraction baffles on internal wave amplitude.

Microbial Sampling: Is It Better to Sample Many Times or Use Large Samples?

1993 ◽  
Vol 27 (3-4) ◽  
pp. 19-25 ◽  
Author(s):  
Charles N. Haas
Keyword(s):  
Small Volume ◽  
Negative Binomial ◽  
Dispersion Parameter ◽  
Microbial Quality ◽  
Large Samples ◽  
Repeated Sampling ◽  
Repeated Samples ◽  
Microbial Sampling

Repeated sampling of a water (raw, Ssished, recreational) is often used to assess microbial quality. Microbial distributions have often been found to be negative binomial distributed in such repeated samples. Under these conditions, it is shown that it is better to use a large number of small volume samples than vice versa, providing that the negative binomial dispersion parameter remains unaffected by volume. Further research is needed to determine if the latter assumption, which influences the conclusion proposed, is valid for various classes of microorganisms in various types of waters.

The effects of surcharged manholes on the travel time and dispersion of solutes in sewer systems

1995 ◽  
Vol 31 (7) ◽  
pp. 51-59 ◽  
Author(s):  
Ian Guymer ◽  
Rob O'Brien
Keyword(s):  
Travel Time ◽  
Moment Method ◽  
In Situ Measurements ◽  
Time Change ◽  
Longitudinal Dispersion ◽  
Laboratory System ◽  
Environmental Load ◽  
Hydraulic Characteristics ◽  
Sewer Systems

Previously, the design of sewer systems has been limited to studies of their hydraulic characteristics, in particular the ability of the system to convey the maximum discharge. Greater environmental awareness has necessitated that new designs, and some existing schemes, are assessed to determine the environmental load which the scheme will deliver to any downstream component. This paper describes a laboratory programme which has been designed to elucidate the effects of manholes on the longitudinal dispersion of solutes. A laboratory system is described, which allows in situ measurements to be taken of the concentration of a fluorescent solute tracer, both up- and down-stream of a surcharged manhole junction. Results are presented from a preliminary series of studies undertaken for a single manhole geometry over a range of discharges, with varying levels of surcharge. Results are presented showing the variation of travel time, change in second moment of the distribution and of a dispersion factor with surcharge, assuming a Taylor approach and determining the dispersion factor using a ‘change in moment’ method. The effect of the stored volume within the manhole is clearly evident. The limitations and the applicability of this approach are discussed.

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