Logic-controlled solid state switchgear for 270 volts dc

A feasibility study to design and demonstrate solid state switchgear in the form of circuit breakers and a power transfer switch is described. The switchgear operates on a nominal 270 V dc circuit and controls power to a load of up to 15 amperes. One circuit breaker may be interconnected to a second breaker to form a power transfer switch. On-off and transfer functions of the breakers or the transfer switch are remotely controlled. A number of reclosures with variable time delay between tripout and reclosure are programmed and controlled by integrated analog and COSMOS logic circuits. A unique commutation circuit, that generates only minimal transient disturbance to either source or load, was developed to interrupt current flow through the main SCR switching element. Laboratory tests demonstrated performance of the solid state circuit breakers over specified voltage and temperature ranges

Quantitative Analysis of Electrotonic Structure and Membrane Properties of NMDA-Activated Lamprey Spinal Neurons

Parameter optimization methods were used to quantitatively analyze frequency-domain-voltage-clamp data of NMDA-activated lamprey spinal neurons simultaneously over a wide range of membrane potentials. A neuronal cable model was used to explicitly take into account receptors located on the dendritic trees. The driving point membrane admittance was measured from the cell soma in response to a Fourier synthesized point voltage clamp stimulus. The data were fitted to an equivalent cable model consisting of a single lumped soma compartment coupled resistively to a series of equal dendritic compartments. The model contains voltage-dependent NMDA sensitive (INMDA), slow potassium (IK), and leakage (IL) currents. Both the passive cable properties and the voltage dependence of ion channel kinetics were estimated, including the electrotonic structure of the cell, the steady-state gating characteristics, and the time constants for particular voltage- and time-dependent ionic conductances. An alternate kinetic formulation was developed that consisted of steady-state values for the gating parameters and their time constants at half-activation values as well as slopes of these parameters at half-activation. This procedure allowed independent restrictions on the magnitude and slope of both the steady-state gating variable and its associated time constant. Quantitative estimates of the voltage-dependent membrane ion conductances and their kinetic parameters were used to solve the nonlinear equations describing dynamic responses. The model accurately predicts current clamp responses and is consistent with experimentally measured TTX-resistant NMDA-induced patterned activity. In summary, an analysis method is developed that provides a pragmatic approach to quantitatively describe a nonlinear neuronal system

Teaching the Elementary Course in Bacteriology

The objectives to be emphasized in courses in bacteriology in the probable order of importance for the elementary course are: A. Vocational Practical Utilization in vocation. B. Health. With some student groups rank first. C. Citizenship. Social-Civic. D. Avocationa. Of minor importance in bacteriology in most cases

Some Errors in the Use of Physico-Chemical Concepts in Physiology of Bacteria

Several erroneous concepts as to the application of certain of the so called laws of physical chemistry to bacteriology are current in the literature pertaining to the physiology of bacteria

What Names Should Be Used for the Organisms Producing Nodules on the Roots of Leguminous Plants?

Strangely enough, there is even yet no agreement among those who are working with the organisms causing nodules upon the roots of leguminous plants as to the name or names to be applied to them. In consequence there is more or less confusion in the literature. At the last meeting of the Society of American Bacteriologists (Madison, Wisconsin) attention was called to the fact that in a recent issue of Soil Science three different names were applied to the same organism: viz. Bacillus radicicola, Rhizobium leguminosarum and Rhizobium radicicolum. It was urged that some agreement be reached

Nomenclature of the Coccaceae

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Test-retest reliability of structural brain networks from diffusion MRI

Structural brain networks constructed from diffusion MRI (dMRI) and tractography have been demonstrated in healthy volunteers and more recently in various disorders affecting brain connectivity. However, few studies have addressed the reproducibility of the resulting networks. We measured the test–retest properties of such networks by varying several factors affecting network construction using ten healthy volunteers who underwent a dMRI protocol at 1.5 T on two separate occasions. Each T1-weighted brain was parcellated into 84 regions-of-interest and network connections were identified using dMRI and two alternative tractography algorithms, two alternative seeding strategies, a white matter waypoint constraint and three alternative network weightings. In each case, four common graph-theoretic measures were obtained. Network properties were assessed both node-wise and per network in terms of the intraclass correlation coefficient (ICC) and by comparing within- and between-subject differences. Our findings suggest that test–retest performance was improved when: 1) seeding from white matter, rather than grey; and 2) using probabilistic tractography with a two-fibre model and sufficient streamlines, rather than deterministic tensor tractography. In terms of network weighting, a measure of streamline density produced better test–retest performance than tract-averaged diffusion anisotropy, although it remains unclear which is a more accurate representation of the underlying connectivity. For the best performing configuration, the global within-subject differences were between 3.2% and 11.9% with ICCs between 0.62 and 0.76. The mean nodal within-subject differences were between 5.2% and 24.2% with mean ICCs between 0.46 and 0.62. For 83.3% (70/84) of nodes, the within-subject differences were smaller than between-subject differences. Overall, these findings suggest that whilst current techniques produce networks capable of characterising the genuine between-subject differences in connectivity, future work must be undertaken to improve network reliability

Slimy and ropy milk

A study of slimy and ropy milk sent for examination to the dairy bacteriological laboratories of Iowa State College has shown the following: 1. Cultures of organisms secured from slimy starters, apparently typical Streptococcus lacticus forms, sometimes showed marked capacity to produce ropiness when inoculated into sterile milk. This slime producing power is evidently a variable characteristic, appearing and disappearing without apparent cause. 2. Associative action of organisms in some cases is responsible for ropiness. Two organisms, neither of which alone can cause ropiness, may, when grown together, cause the medium to become slimy. 3. Bacterium (lactis) viscosum is one common cause of slimy milk. 4. Certain peptonizing bacteria, as Bact. peptogenes, produce a very slimy residuum after digestion of the casein. 5. Bacterium bulgaricum and certain related high acid organisms frequently produce marked viscosity in milk. Sliminess in milk is apparently due to different causes with different organisms: 1. Gum and gum-like capsular materials partially soluble, or at least swelling in water, al\u27e frequently the same. 2. In many cases there seems to be a direct relationship between chain formation of streptococcus and the development of ropiness, likewise between the numbers of bacteria and ropiness. 3. Associative action between two distinct organisms resulting in great increases in number of each is not uncommon as a cause of ropiness. Methods of control and prevention of slimy milk are discussed. Keys to the organisms that have been described as responsible for slimy production in milk are presented. An attempt has been made to clear up synonymy. Descriptions of thirty-three species of bacteria that have been found associated with milk are given, and the literature reviewed

The Third Way for the Third Sector: Using Design to Transfer Knowledge and Improve Service in a Voluntary Community Sector Organisation

This paper describes a two-year Knowledge Transfer Partnership that concluded in September 2011. Knowledge Transfer Partnerships (KTP) is a UK-wide activity that helps organisations to improve their competitiveness and productivity by making better use of knowledge, technology and skills within universities, colleges and research organisations. This paper details the outcome of a KTP between Age UK Newcastle and Northumbria University’s School of Design that aimed to use Design approaches to improve the charity’s services. This paper will describe the recent context for organisations operating in the Voluntary Community Sector and discuss the relevance of a Design approach to both the improvement of customer services in this circumstance, as well as the transfer of knowledge to a capacity-starved organisation. It will also document how Design was used to achieve both of these aims, and the resulting impact of this engagement on the organisation and stakeholders