A hybrid drive combines the features of an HDD and an SSD into one unit. It contains a large HDD and a smaller SSD cache to improve performance of frequently accessed files. A hybrid drive can offer almost the same performance as an SSD and it can contain more capacity. The price is also lower than of an SSD. The main market for this drive are the laptop users as these devices can accommodate no more than one drive.
The solid state drive technology is improving quickly and new SSD models are being introduced often. However, they have not gained popularity among many users. We still find that HDDs are still dominating the market. Sales of SSDs are expected to escalate and overturn that of HDDs after 2020.
When SSDs were first introduced into the market, manufacturers' made sure that they fit into the slots and bays initially used by the HDDs. As such they had the 3.5 and 2.5 inch form factors. However, as technlogy advances, more form factors emerged. Smaller form factors that directly interfaces with PCIe and NVMe slots emerged. These incuded the mSATA, PCIe and M.2, form factors.
Martial Célestin
Martial Lavaud Célestin (October 4, 1913 – February 4, 2011) was the first Prime Minister of Haïti. He was born in Ganthier and worked as a lawyer. President Leslie Manigat made him prime minister in March 1988. A coup removed Célestin from power on 20 June 1988.
Norwegian Crusade
The Norwegian Crusade was one of several religious wars in which European countries fought against Muslims in Turkey and the Middle East. The First Crusade was 1095-1099. The Norwegian Crusade was next, from 1107 to 1110. King Sigurd I led the crusade. Sigurd was the first European king to go on crusade to the Holy Land. He did not lose any battles. The Norwegian crusade seems to have been similar to earlier Viking raids.
Jumping spider
Jumping spiders belong to the family "Salticidae". These spiders catch their prey by jumping on them.
Species live in many habitats, from leaves lying on the ground, to the tops of trees in the forest, and even way up on Mt. Everest. They are found on every continent in the world except for Antarctica.
At present, 5026 species in 530 genera have been found. They are actually the largest family of spiders, with about 13% of all species.
They are easy to identify because their eye pattern is distinctive. They have eight eyes, two of which are very large, and because their faces form a flat surface, facing where they are going.
They often hunt high up in bushes, or on vertical walls. To save themselves from falling they do something very much like what climbers do to protect themselves in the mountains. Humans tie a rope to the mountain and attach the other end to the harness they wear. Jumping spiders attach silk from their spinnerets to the thing on which they are standing and then they jump. While they are moving through the air they make silk so that there is always a safety rope trailing out behind them.
Jumping spiders can jump long distances for their size, as much as 16 cm. When they jump, they use their hind legs. They raise their front legs to be ready to grab their prey.
Many other kinds of spider hunt at night, but jumping spiders depend on their eyes, so they like to come out in the daytime. Often they will find a sunny spot on a wall or tree trunk.
There are however many variations, and many surprising aspects. For one thing, Salticids do not necessarily follow a straight path in approaching prey. They may follow a circuitous course, sometimes even a course that takes the hunter through places where the prey is not visible. Such complex behaviour is hard to reconcile with an organism that has such a tiny brain. Some spiders in species of "Portia" can take long detours from one bush down to the ground, then up the stem of another bush to capture a prey item on a particular leaf. Such behaviour is the subject of research.
Because they have very good eyes, jumping spiders can see human beings when they approach. Some jumping spiders may run away from approaching humans, and others seem not to be very much afraid. But either way a jumping spider will watch a nearby human being. When they do not run away, but do turn to keep watch over a human being, it may seem that they are interested in us. Some of them will even jump from where they are sitting on branches, rocks, etc. onto a person's finger or camera. These spiders only bite to get something to eat or to defend themselves, so if they jump on somebody's hand they will not bite. People get bitten if they pinch or squeeze a jumping spider.
Jumping spiders are able to climb glass and other very smooth surfaces because besides having two claws on each foot they also have sticky hairs (called "scopulae") that hold onto the surface. Many tiny ends on each hair are held to the glass by Van der Waals forces, the force that will make two very flat sheets of glass stick tightly together without any glue.
Jumping spiders are able to see very clearly. Two of their eight eyes are very large and are complicated inside. The eyes cannot move, so the spider will often move its body to look at what it wants to see. However, it can also move the retinas of its two main eyes on the inside of the eye, so the center of the eye's picture can be moved. So the jumping spider has binocular vision.
Very few kinds of jumping spider make webs; instead they use their silk for their safety rope and also to make a kind of tent where they sleep at night, shed their skins (molt), lay their eggs, and enjoy a long sleep during winter (hibernate). Their silk comes out of their spinnerets (see diagram).
William Lipscomb
William Nunn Lipscomb, Jr. (December 9, 1919– April 14, 2011) was a Nobel Prize-winning American inorganic and organic chemist. He worked in nuclear magnetic resonance, theoretical chemistry, boron chemistry, and biochemistry.
Lipscomb was born in Cleveland, Ohio. His family moved to Lexington, Kentucky in 1920.He lived there until he earned his Bachelor of Science degree in Chemistry at the University of Kentucky in 1941. Then he earned his Doctor of Philosophy degree in Chemistry from the California Institute of Technology (Caltech) in 1946.
From 1946 to 1959, he taught at the University of Minnesota. From 1959 to 1990, he was a professor of chemistry at Harvard University. After 1990, he became a professor emeritus at Harvard.
Lipscomb went to live in Cambridge, Massachusetts until his death in 2011 from pneumonia.
Lipscomb was one of the first people to use nuclear magnetic resonance (NMR) to study chemical structures. He learned out how to look at NMR data to find what atoms are connected together in a molecule. This is called "chemical shift".
Lipscomb studied molecules. These molecules included boron atoms. Lipscomb used this work to learn basic ideas about how atoms form chemical bonds. Lipscomb and his students created many important ideas in the field of theoretical chemistry. His work on boron compounds won a Nobel Prize in 1976. Three of his students went on to also win separate Nobel Prizes in Chemistry.
Lipscomb's later research was on the atomic structure of proteins. He studied how enzymes work. His group used x-ray diffraction to measure the three-dimensional structure of these proteins. He calculated the exact location of every single atom in these large molecules. Lipscomb then studied these details to learn how the molecules work in biological systems.
Carboxypeptidase A was the first protein structure from Lipscomb's group.
Five books and published collections of writings are dedicated to Lipscomb.
I Am Weasel