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The following is not an answer to the original question: "Are Gram negative bacteria classified as such because of their negative membrane potential?" but to the questions later in the text. Usually the membrane potential is given for the inner cytosolic part and the extracellular space, for E. Coli it is around -120 mV; see also this article. Due to the ...


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Short answer The distinction between Gram positive (Gram+) and negative bacteria (Gram-) has absolutely nothing to do with membrane potentials; it is all about the Gram staining procedure. Background The Gram staining was named after the Danish bacteriologist Hans Christian Gram, who originally devised it in 1882 (Gram, 1884). Gram staining is a common ...


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The terminology around EEGs is variable, dependent on the context; Brain wave is fine, but has a bit of a popular undertone; Oscillation, as per the deleted answer, implicitly refers to a longer-term behavior, i.e., something periodic (EEG); Waveform is often used to describe a single event with a recognizable shape (ERP, compound action potentials, ...


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The so called horizontal axis (rosto-caudal) is parallel to the body of the rat. Vertical is just vertical when the rat is in its normal standing position and medio-lateral is horizonral and perpendicular to the rat's body. The head is the origin.


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Wikipedia has a quite didactic article on this: https://en.wikipedia.org/wiki/Anatomical_terms_of_location#Axes These terms are complementary with a mathematical coordinate system: if you are describing a system of axis for a cylinder, you will need to specify that (e.g.) $z$ is along its symmetry axis, here you will say that $z$ is along the rostro-caudal ...


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Is there a difference? Yes, they are quite different things. What is group selection? Group selection is an view of evolution where selection acts at the level of the group, rather than the individual. It suggests that selection is mediated by fitness of the population, and leads to conclusions of things occurring for "the good of the species". It is ...


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The concepts are very similar but there are a few differences. Firstly, fitness is usually applied to alleles or genotypes, reproductive success to individuals. Secondly (and partially as a consequence of this), fitness is an average or idealised/expected property across a population; but actual reproductive success per individual is stochastic. ...


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The whole point of Darwin's theory was that transition from one species to another is extremely slow and gradual. There are plenty of quotes in "Origin of Species" stating this, and also affirming that there is no clear boundary between species and subspecies, or "races". Quotes from Origin of Species > Variation under Nature (Chapter 2) Quote 1 ...


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Nonclinical depression is a popular term for the natural reactions to the external factors, such as loss, seasonal changes, emotional stress http://www.depressionfree.com/non-clinical.html while the major types of clinical depression are as follows: Major Depressive Disorder Major depression is a severe mental disorder that deeply affects an individual’s ...


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In the vertical plane, bending of the fingers is indeed referred to as flexion, while straightening is called extension. In the horizontal plane, spreading the fingers is called abduction, and approximation is called adduction (Fig. 1). Fig. 1. Finger movements and terminology. source: US Dept. of Veteran Affairs


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The absorbed dose describes the amount of radiation absorbed by an object or person, i.e., the amount of energy that radioactive sources deposit in materials through which they pass. The units for absorbed dose are the radiation absorbed dose (rad), or better: the gray (Gy) unit. One gray dose is equivalent to one joule radiation energy absorbed per ...



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