“One role of spine motility might be to enable a searching function during synaptogenesis, allowing for more efficacious neuronal connectivity in the neuronal thicket.”—
hehe neuronal thicket.
on haters, doubters, and those who say thee nay
I do not understand the cultural fascination with being “hated on”. If people doubt me, so what? If I fail it will not be because of them, and if I succeed I will not look for their congratulations. By not knowing me enough to have faith in my abilities they have made themselves background noise. I care about their existence as much as a person whom I have never met, because clearly they have never met me.
How bacteria travel: Flagella
One of the ways in which bacteria move around is through the use of flagella.
Flagella are thin filaments attached to the surface of bacteria. They are made of building blocks called flagellin which travel out through the hollow center of the filament and attach at the tip. Bacteria have a really cool way of determining when their flagella are long enough and I’ll be devoting a different post to this mechanism.
Flagella can be either polar or peritrichous. That is, one or more flagella are located at one end of the bacterium (polar, Fig 2B) or many are located at various points across its entire surface (peritrichous, Fig 2C).
Different species of bacteria have different flagellar distributions (and some have none!) and this characteristic can be used to help identify different types of bacteria. Some bacteria can even switch which type of flagellar distribution they express depending on the type of motility they wish to use!
Polar flagella are used for swimming motility in liquid environments. Peritrichous flagella are used for swarming motility across solid surfaces. Most flagella use a proton motive force to power the rotation of the filament, but other ions (such as sodium) have also been shown to power the movement.
Walnuts May Boost Semen Quality
Young, healthy men who added a daily dose of walnuts to their usual diet had improved semen parameters, a randomized trial showed.
After 12 weeks, those who ate walnuts had better sperm vitality, motility, and morphology compared with those who avoided tree nuts altogether (P≤0.03 for all), according to Wendie Robbins, PhD, of the University of California Los Angeles, and colleagues.
Walnuts also were associated with improvements in serum omega-6 and omega-3 fatty acids, the researchers reported online in Biology of Reproduction.
“Whether adding walnuts to the diet will go beyond the shifts in sperm parameters as seen in this study to improving birth outcomes for men within fertility clinic populations or in the general population is not yet known and will require further research,” they wrote.
Polyunsaturated fatty acids — which are found in high concentrations in fish, fish oil supplements, flax seed, and tree nuts — have been shown in animal and human laboratory studies to be involved in sperm maturation and membrane function. However, not all clinical studies of male fertility have shown differences in polyunsaturated fatty acid concentrations between fertile and infertile participants.
Nuts, and walnuts in particular, have a high concentration of alpha-linolenic acid — a natural source of omega-3 — in addition to omega-6 fatty acids, antioxidants, and micronutrients like folic acid.
Robbins and colleagues set out to explore whether adding walnuts to a Western-style diet would improve semen quality. They randomized 117 healthy men ages 21 to 35 (mean age 25) with no known history of infertility to add 75 grams of whole-shelled walnuts a day to their usual diet or to continue their usual eating habits while avoiding tree nuts. Read more here.
VII. E. The Primary and Secondary Processes
[…] A current of this kind in the apparatus, starting from unpleasure and aiming at pleasure, we have termed a ‘wish’; and we have asserted that only a wish is able to set the apparatus in motion and that the course of the excitation in it is automatically regulated by feelings of pleasure and unpleasure. The first wishing seems to have been a hallucinatory cathecting of the memory of satisfaction. Such hallucinations, however, if they were not to be maintained to the point of exhaustion, proved to be inadequate to bring about the cessation of the need or, accordingly, the pleasure attaching to satisfaction.
A second activity—or, as we put it, the activity of a second system—became necessary, which would not allow the mnemic cathexis to proceed as far as perception and from there to bind the psychical forces; instead, it diverted the excitation arising from the need along a roundabout path which ultimately, by means of voluntary movement, altered the external world in such a way that it became possible to arrive at a real perception of the objection of satisfaction. We have already outlined our schematic picture of the psychical apparatus up to this point; the two systems are the germ of what, in the fully developed apparatus, we have described as the Ucs. and Pcs.
In order to be able to employ the power of movement to make alterations in the external world that shall be effective, it is necessary to accumulate a great number of experiences in the mnemic systems, and a multiplicity of permanent records of the associations called up in this mnemic material by different purposive ideas.
—Freud, The Interpretation of Dreams, p. 595