In last week’s letter I wrote about the hypodermic needle as my weekly invention. While writing the letter I thought of some shots I received while in the military and they used something else. It was A jet injector, also commonly referred to as an air gun, air jet injector, pneumatic injector, or jet gun injector, is a needle-free instrument that uses a high-pressure stream of liquid medicament to penetrate the skin and achieve a percutaneous administration of medicine or vaccine. The concept most resembles a powerful squirt gun penetrating through skin.
These jet injectors, known as high workload jet injectors, were designed for use in mass immunizations, in which a large population needed to be vaccinated at a rapid rate. The concept reduced the overuse and disposal of single-use syringes and needles, and prevented the accidental needle stick injuries to the immunizing staff.
After reading a bit about them, I noticed the military stopped their use in 1997. This was due to three major concerns.
Research conducted by Samir Mitragotri, a chemical engineer at the University of California, visually captured the discharge of multiple-use nozzle jet injectors using high-speed microcinematography. The photos in the following link demonstrate a close-up look at the jet injection process. Most importantly, notice in the images when the high velocity stream penetrates the skin there is extensive splash back.
Aaron Ismach, inventor of the most widely used jet injector, the Ped-O-Jet, found earlier devices sucked fluid directly upon the outside of the nozzle orifice back into internal fluid pathway and drug reservoir. This phenomenon allows foreign particles to contaminate the sterile vaccine. Ismach declared in his 1962 patent that his invention overcame this danger.
Kale and Momin (2014) found during Phase 2 of the injection process there would be a backwards flow where the jet spray would shoot back out of the hole towards the jet injector. This would be an expected phenomenon in every injection due to the continuous depletion of pressure where the volumetric rate of hole formation would eventually be less than the volumetric rate of the jet impinging the skin. This continuous decrease in pressure would create a retrograde, or backwards, flow, whereupon the jet injector's nozzle, internal fluid pathway and drug reservoir would become contaminated.
The military stopped the use of this device due to Veterans Administration claims of patients becoming infected with Hepatitis that could not be explained with another vector.
Due to health risks the gun injector’s use was totally stopped 12 years ago by all, as in some cases, the jet injectors could bring blood or other body fluids to the surface of the skin while the vaccine was being administered. Those fluids could contaminate the injector, creating the possibility that viruses could be transmitted to another person being vaccinated with the same device.
have some favorite sea animals, the best being the leatherback sea turtle. Its primary food source is jellyfish which by the way are my least favorite. I dislike them more than sharks as I must say other than what I hear about sharks they truly have not impacted my life as much as those slimy jellyfish. The jellyfish have closed beaches, I guess so have sharks. I have been stung by a jellyfish but never received a shark bite.
The world’s ecosystem is one of need for food. In college they used an island as the example. If the grass was plentiful, the mice that ate the grass became plentiful. Then the foxes that ate the mice in turn grew plentiful. It is true there could be a perfect balance as long as there wasn’t a big change in the numbers of mice or fox. But the entire process is more like a wave. Grass grows, mice population grows, fox population grows then the mice population decreases, also due to lack of food the fox population decreases etc. Pretty much the one thing that stays constant is change.
If there were only grass and mice it would be a little different. Grass grows, the mice population grows, they eat too much grass so its area decreases and in turn the mice population decreases. This process is just easy peasy to understand and probably why it is the example in college
This state protects eel grass; small sticky jellyfish like eel grass so now we are getting an abundance of those small dime sized jellyfish. They are an annoyance but you can just wipe them off. However they have joined forces with another type of jellyfish and now are getting stingers. To some people this can be dangerous at least they currently are located pretty much only in the Waquoit bay area.
The other day when I spouted off about the increase in grey seal population bringing in a host of predators to the Cape’s waters it is the same principal.
Now we have two whale species that are rare to our waters although not unheard of but unusual as they rarely visit. It is the bowhead whale and sei whales swimming along with our local North Atlantic right whales. They were all seen feeding side by side.
The number of sei whales in Cape Cod Bay was 40. When mature they are the third biggest whale in the world. On this day 40 percent of all the right whales left in the world were in Cape Cod Bay or 217.
Again the available food in Cape Cod Bay of zooplankton is at an all-time high. The normal population is about 5,000 organisms per cubic meter of seawater. This year the count is from 40,000 to 77,000 per cubic meter.
“The food resource is the thickest we have seen in 32 years,” Charles “Stormy” Mayo, head of the right whale ecology program at the Center for Coastal Studies, said of the zooplankton that whales consume.
Have you ever wondered what the caloric intake of a right whale is? North Atlantic right whales need a lot of food each day — the caloric equivalent of 3,000 Big Macs — and right now there’s plenty of it in Cape Cod Bay, in the form of a tiny crustacean.
During their feeding cycle they eat about 4% of their weight daily. It is probably a good thing this as feeding only lasts for about 120 days a year. Most baleen whales spend about four to six months in the summer feeding intensively in high-latitude, productive waters. They spend the next six to eight months traveling and breeding.
Whales gain about 16% to 30% of their total body weight during a feeding season.
Throughout the traveling and breeding season, baleen whales eat much less or not at all. Blubber gained during the feeding season sustains the whale during the winter months. A baleen whale's thick blubber layer stores fat; it is an energy reserve that is necessary during the traveling and breeding seasons. Blubber makes up 27% of a blue whale's body weight, 23% of a fin whale, 21% of a sei whale, 29% of a gray whale, and 36% to 45% of a right whale.
In the Sunday Cape Cod Times it was reported they found a dead minke whale on a Harwich beach. Harwich is on the Nantucket Sound side of the Cape. It is in those waters where the seals and sharks primarily hunt. It was small, and the paper said it was only 13 feet long. It looks like the International Fund for Animal Welfare will perform a necropsy to find the cause of death.
The size is probably correct as the minke is the second smallest of the baleen type whales. The smallest being the pigmy right whale. The largest a minke will grow for the female at 26 feet and the male at 23 feet.
To me this dead whale’s size is slightly more than the birth size as when born they are from 8 to 9 feet long. However the world population for this type of whale is in excess of 500,000. This species is considered as in the “Not at risk category.”
About four years ago I started using something called Soap Berries. I am just reporting in that I have stopped using them. I found that the clothes started to smell musty. I have since gone back to Tide. Other people I know still use them.
Here is an excerpt from a 2013 letter: This is a bit on soap berries mentioned in last week's letter. If interested just Google these things: the tree that grows them is Sapindus Mukorossi . It comes from a tropical/sub-tropical area of the world and mostly used in India and China. If you live in Florida/California you can possibly grow the tree. You only use the shell that surrounds the seed to wash with. I have found some interesting things while reading about them. They can be used to make your own shampoo or pet shampoo or soap. They can be used to spray on veggies as an insect deterrent. When you finish doing 5-8 loads you can compost the small husks into your garden. Front loaders like them as they do not make high suds. You will no longer need softener for your clothes. I just wonder why they have not been around earlier as soap is expensive.
I now know that we Americans as a population like people and clothes that have an attractive scent. It is how we choose our soaps, shampoo, and many other personal products. However these berries are still sold on Amazon and I noticed that many sources are now made in the USA. I personally do not think I will try them again but feel it is a good idea and if you want a product that is natural try it. Maybe if a natural scent could be added I might try them again.