Author Archives: Erik Johnson

Hydrothermal Vents: Home Sweet Home?

One of the most wildly debated and difficult to answer questions in any field of science is the origin of life. From where did we come? One of the most widely accepted hypotheses of our origin points to hydrothermal vents, fissures deep within the ocean that spew water heated by geothermal activity. The water these vents exude is filled with minerals and as a result dense communities of deep sea life congregate around them, as seen in the video below uploaded by Youtube user MrCoxyWoxy.

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What makes some researchers believe this is where it all began? The alkaline hydrothermal vents interact with the carbon dioxide-rich seawater in a bunch of redox reactions, in which electron acceptors, in this case the carbon dioxide, receive electrons from electron donors such as molecular hydrogen. These reactions are exothermic and release a lot of energy, meaning that hydrothermal vents are a source of sustained chemical energy from beneath the sea floor. Such an environment, ideal for the redox reactions, is a great candidate for the origin of life. It’s even been demonstrated that deep sea vents can create the same type of proton-motive force seen in living organisms.

Redox reactions are how life harnesses chemical energy. When we digest food, our cells carry out redox reactions in order to extract the nutrients in it. Since hydrothermal vents are full of the building blocks required for redox reactions involving hydrocarbons like the ones we utilize for food today, it seems possible that the chemical processes our bodies use originated in hydrothermal vents.

By Erik Johnson

Spirulina, Chlorella, and “Superfoods” – Yuppie Bunk or True Superfoods?

Even the most brief of visits to the aisles of a health food store such as Whole Foods will introduce you to a bevy of products with outlandish marketing claims. Supplement labels would have you believe that all of your problems are only a few of their company’s products away from being resolved. Lax (but improving) regulations regarding supplement labels and a tendency for some less scrupulous companies to lie outright about the contents of their products creates a treacherous landscape for those trying to enhance their health through supplementation.

With labeling practices as dubious as these in place, it is easy to adopt a cynical attitude towards any sort of claim made about a novel supplement. This attitude is warranted indeed. Many companies will commission professionals with questionable credentials and presumably extinct scruples to advocate their products. How many times have you seen a toothpaste that “four out of five dentists” advocate, with convenient omissions as to the amount of dentists polled, their identities, and their credentials? All of these factors serve to make it very difficult to make informed supplementation decisions, especially when marketing claims are considered.

Two examples of this are chlorella and spirulina. Chlorella is a green algae while spirulina is a blue-green cyanobacterium, a type of bacterium similar to algae. Both are highly edible, and marketed in a very similar way. The word “superfood” is liberally applied to both to imply medicinal benefits beyond their nutritional value. Chlorella, however, has little medicinal benefit. It’s basically a decent plant source of vitamin b12, a vitamin found mostly in animal products. Spirulina is far more interesting. In addition to containing a large amount of both b12 and protein, it has a compound that modulates the immune system to both increase immune response and decrease inflammation – a seemingly contradictory effect considering that inflammation is a reaction of the immune system to cell damage! To this end, it has been demonstrated to assist with nasal congestion related to seasonal allergies. These two supplements demonstrate how two supplements can be touted equally and have much different medical relevance.

– Erik Johnson

Taken from www.algaeindustrymagazine.com

Chlorella, a single-celled green algae.

Taken from spirulina.sg

Spirulina, a photosynthetic cyanobacterium.

Analog vs. Digital Synthesizers – What Are They, and Which Makes Better Music?

In 1983, the music world was shaken by the introduction of a new instrument, the Yamaha DX7. The DX7 was the first digital synthesizer – the first instrument to generate sounds from data – to overcome the challenges of its digital predecessors and experience commercial success. It was both portable and affordable, and it had new features its analog predecessors lacked such as the ability to save sounds in digital memory for later. The DX7 went on to shape the sound of much of the music in the 80s and 90s, and it is credited with bringing about the decline of analog synths.

Analog synthesizers don’t seem to be gone for good, though. Many companies are beginning to make analog synths again. For example, Korg recently reissued its classic MS20 and Dave Smith Instruments recently announced the all-new Prophet 6. Given the advantages of digital instruments, why are companies bothering? Why is there a demand for new analog instruments? The answer lies in the way they generate sound.

Sound is the variation of pressure in the air as perceived by the eardrum. When sound is recorded with an analog system, it is converted into an electrical signal where the height of the sound wave is proportional to signal strength. A stronger signal will model a taller wave. When sound is recorded on a digital system, wave height is recorded as a number. This means analog systems generate and capture sound continuously while digital systems generate and capture sounds in steps. The tiny loss of detail that comes with capturing sound in steps is called “loss”. So digital systems have loss while analog systems are “lossless”. This is also the reason some people prefer analog sounds to digital sounds – they feel that analog instruments sound more smooth and “liquid” because they create sound continuously instead of in steps.

Two important differences and digital signal are bandwidth, defined as the range of frequencies they can capture, and signal-to-noise or S/N ratio, the ratio of the amount of desired sound to unwanted background noise. Analog system bandwidth is constrained by the quality of the circuits used, and digital system bandwidth is constrained by the sampling rate, the speed at which the system measures a sound wave. In recent years, many digital systems have achieved sampling rates high enough to functionally match the quality of analog sounds, causing many to call into question whether it’s even possible to hear a difference between an analog signal and a digital signal of sufficient quality. Will digital ever really kill analog? Only time will tell. I maintain that both are very useful and relevant types of instruments for music production, depending on the type of sound desired. I’ve attached a video with analog and digital synthesizers from the same company played together for comparison. See which one you like more!

– Erik Johnson

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