Bioluminescence

Bioluminescence

Bioluminescence


Bioluminescence is the production and emission of light by a living organism as the result of a chemical reaction during which chemical energy is converted to light energy. Its name is a hybrid word, originating from the Greek bios for “living” and the Latin lumen “light”.

Adenosine triphosphate (ATP) is involved in most instances. The chemical reaction can occur either inside or outside the cell. In bacteria, the expression of genes related to bioluminescence is controlled by an operon called the Lux operon. Bioluminescence has appeared independently several times (up to 30 or more) during evolution.

Bioluminescence occurs in marine vertebrates and invertebrates, as well as microorganisms and terrestrial animals. Symbiotic organisms carried within larger organisms are also known to bioluminesce.

You tube – Bioluminescence

Recellularized Heart

Recellularized Heart

Recellularized Heart


A biologist at the University of Minnesota, Doris Taylor, has discovered a way to make heart transplants more successful. By removing the cells of the donor heart and replacing them with the patient’s cells, a “recellularized heart” would reduce waiting time for donated heart organs and minimize the risk of patient rejection of the new heart.

Currently, about half of the patients receiving heart transplants die within five years, despite current repair procedures and drugs available to minimize rejection. Ms. Taylor has perfected her procedure in rats and expects, if all goes well, that the new transplant procedure will be available for humans in about 10 years.

Magnetic Levitating Train

The term “maglev” (Magnetic Levitation) refers not only to the vehicles, but to the railway system as well, specifically designed for magnetic levitation and propulsion. All operational implementations of maglev technology have had minimal overlap with wheeled train technology and have not been compatible with conventional rail tracks. Because they cannot share existing infrastructure, these maglev systems must be designed as complete transportation systems. The Applied Levitation Maglev system is inter-operable with steel rail tracks and would permit maglev vehicles and conventional trains to operate at the same time on the same right of way.
There are three primary types of maglev technology:
For electromagnetic suspension (EMS), electromagnets in the train repel it away from a magnetically conductive (usually steel) track.
electrodynamic suspension (EDS) uses electromagnets on both track and train to push the train away from the rail.
stabilized permanent magnet suspension (SPM) uses opposing arrays of permanent magnets to levitate the train above the rail.
Electro magnetic suspension
In current electromagnetic suspension (EMS) systems, the train levitates above a steel rail while electromagnets, attached to the train, are oriented toward the rail from below. The electromagnets use feedback control to maintain a train at a constant distance from the track, at approximately 15 millimeters.
Electrodynamic suspension
EDS Maglev Propulsion via propulsion coils
In electrodynamic suspension (EDS), both the rail and the train exert a magnetic field, and the train is levitated by the repulsive force between these magnetic fields. The magnetic field in the train is produced by either electromagnets or by an array of permanent magnets. The repulsive force in the track is created by an induced magnetic field in wires or other conducting strips in the track.
At slow speeds, the current induced in these coils and the resultant magnetic flux is not large enough to support the weight of the train. For this reason the train must have wheels or some other form of landing gear to support the train until it reaches a speed that can sustain levitation.
Propulsion coils on the guideway are used to exert a force on the magnets in the train and make the train move forward. The propulsion coils that exert a force on the train are effectively a linear motor: An alternating current flowing through the coils generates a continuously varying magnetic field that moves forward along the track. The frequency of the alternating current is synchronized to match the speed of the train. The offset between the field exerted by magnets on the train and the applied field creates a force moving the train forward.
Stabilized Permanent Magnet suspension

SPM maglev systems differ from EDS maglev in that they use opposing sets of rare earth magnets (typically neodymium alloys in a Halbach array) in the track and vehicle to create permanent, passive levitation; i.e., no power is required to maintain permanent levitation. With no current required for levitation, the system has much less electromagnetic drag, thus requiring much less power to move a given cargo at a given speed.Because of Earnshaw’s theorem, SPM maglev systems require a mechanism to create lateral stability (i.e., controlling the side-to-side movement of the vehicle). One way to provide this stability is to use a set of coils along the bottom of the magnet array on the vehicle being levitated, which centers the vehicle over the rails by means of small amounts of current. Because the voice coils are not needed to provide lift and there is almost no drag, this system uses less power than other maglev systems: when the vehicle is centered over the rails, it uses no power. As the vehicle navigates a curve, the controller moves the vehicle to a ‘balance point’ inside the curve so that the (magnetic) centripetal pull of the magnetic rails in the ground offset the vehicle’s (kinetic) centrifugal momentum. This balance point varies based on the vehicle’s weight, which the controller automatically accounts for, resulting in zero steady state power

consumption.

Magnetic Levitating Train

Magnetic Levitating Train

The term “maglev” (Magnetic Levitation) refers not only to the vehicles, but to the railway system as well, specifically designed for magnetic levitation and propulsion. All operational implementations of maglev technology have had minimal overlap with wheeled train technology and have not been compatible with conventional rail tracks. Because they cannot share existing infrastructure, these maglev systems must be designed as complete transportation systems. The Applied Levitation Maglev system is inter-operable with steel rail tracks and would permit maglev vehicles and conventional trains to operate at the same time on the same right of way.

Levitation Effect

Levitation Effect

There are three primary types of maglev technology:

Electromagnetic suspension (EMS) Electromagnets in the train repel it away from a magnetically conductive (usually steel) track.

Electrodynamic suspension (EDS) uses electromagnets on both track and train to push the train away from the rail.

Stabilized permanent magnet suspension (SPM) uses opposing arrays of permanent magnets to levitate the train above the rail.

Electro magnetic suspension

In current electromagnetic suspension (EMS) systems, the train levitates above a steel rail while electromagnets, attached to the train, are oriented toward the rail from below. The electromagnets use feedback control to maintain a train at a constant distance from the track, at approximately 15 millimeters.

Electrodynamic suspension

EDS Maglev Propulsion via propulsion coils.In electrodynamic suspension (EDS), both the rail and the train exert a magnetic field, and the train is levitated by the repulsive force between these magnetic fields. The magnetic field in the train is produced by either electromagnets or by an array of permanent magnets. The repulsive force in the track is created by an induced magnetic field in wires or other conducting strips in the track.

At slow speeds, the current induced in these coils and the resultant magnetic flux is not large enough to support the weight of the train. For this reason the train must have wheels or some other form of landing gear to support the train until it reaches a speed that can sustain levitation.

Propulsion coils on the guideway are used to exert a force on the magnets in the train and make the train move forward. The propulsion coils that exert a force on the train are effectively a linear motor: An alternating current flowing through the coils generates a continuously varying magnetic field that moves forward along the track. The frequency of the alternating current is synchronized to match the speed of the train. The offset between the field exerted by magnets on the train and the applied field creates a force moving the train forward.

Stabilized Permanent Magnet suspension

SPM maglev systems differ from EDS maglev in that they use opposing sets of rare earth magnets (typically neodymium alloys in a Halbach array) in the track and vehicle to create permanent, passive levitation; i.e., no power is required to maintain permanent levitation. With no current required for levitation, the system has much less electromagnetic drag, thus requiring much less power to move a given cargo at a given speed.Because of Earnshaw’s theorem, SPM maglev systems require a mechanism to create lateral stability (i.e., controlling the side-to-side movement of the vehicle). One way to provide this stability is to use a set of coils along the bottom of the magnet array on the vehicle being levitated, which centers the vehicle over the rails by means of small amounts of current. Because the voice coils are not needed to provide lift and there is almost no drag, this system uses less power than other maglev systems: when the vehicle is centered over the rails, it uses no power. As the vehicle navigates a curve, the controller moves the vehicle to a ‘balance point’ inside the curve so that the (magnetic) centripetal pull of the magnetic rails in the ground offset the vehicle’s (kinetic) centrifugal momentum. This balance point varies based on the vehicle’s weight, which the controller automatically accounts for, resulting in zero steady state power consumption.
YouTube-Superconducting Maglev Train Models

The Vitruvian Man

 

 

The Vitruvian Man (c. 1485) Accademia, Venice.

The Vitruvian Man (c. 1485) Accademia, Venice.

A study of the proportions of the human body, the Head of an Angel, for The Virgin of the Rocks in the Louvre, a botanical study of Star of Bethlehem and a large drawing (160×100 cm) in black chalk on coloured paper of the The Virgin and Child with St. Anne and St. John the Baptist in the National Gallery, London. This drawing employs the subtle sfumato technique of shading, in the manner of the Mona Lisa. It is thought that Leonardo never made a painting from it, the closest similarity being to The Virgin and Child with St. Anne in the Louvre.

Other drawings of interest include numerous studies generally referred to as “caricatures” because, although exaggerated, they appear to be based upon observation of live models. Vasari relates that if Leonardo saw a person with an interesting face he would follow them around all day observing them. There are numerous studies of beautiful young men, often associated with Salai, with the rare and much admired facial feature, the so-called “Grecian profile”. These faces are often contrasted with that of a warrior. Salai is often depicted in fancy-dress costume.

 Leonardo is known to have designed sets for pageants with which these may be associated. Other, often meticulous, drawings show studies of drapery. A marked development in Leonardo’s ability to draw drapery occurred in his early works. Another often-reproduced drawing is a macabre sketch that was done by Leonardo in Florence in 1479 showing the body of Bernardo Baroncelli, hanged in connection with the murder of Giuliano, brother of Lorenzo de’Medici, in the Pazzi Conspiracy. With dispassionate integrity Leonardo has registered in neat mirror writing the colours of the robes that Baroncelli was wearing when he died. Leonardo as observer, scientist and inventor.

Mona Lisa

 

Mona Lisa or La Gioconda(1503–1505/1507)—Louvre, Paris, France

Mona Lisa or La Gioconda(1503–1505/1507)—Louvre, Paris, France

Among the works created by Leonardo in the 1500s is the small portrait known as the Mona Lisa or “la Gioconda”, the laughing one. The painting is famous, in particular, for the elusive smile on the woman’s face, its mysterious quality brought about perhaps by the fact that the artist has subtly shadowed the corners of the mouth and eyes so that the exact nature of the smile cannot be determined. The shadowy quality for which the work is renowned came to be called “sfumato” or Leonardo’s smoke. Vasari, who is generally thought to have known the painting only by repute, said that “the smile was so pleasing that it seemed divine rather than human; and those who saw it were amazed to find that it was as alive as the original”.

Other characteristics found in this work are the unadorned dress, in which the eyes and hands have no competition from other details, the dramatic landscape background in which the world seems to be in a state of flux, the subdued colouring and the extremely smooth nature of the painterly technique, employing oils, but laid on much like tempera and blended on the surface so that the brushstrokes are indistinguishable. Vasari expressed the opinion that the manner of painting would make even “the most confident master … despair and lose heart.” The perfect state of preservation and the fact that there is no sign of repair or over painting is extremely rare in a panel painting of this date. 

The Last Supper

 

The Last Supper

The Last Supper (1498)—Convent of Sta. Maria delle Grazie, Milan, Italy

 

Leonardo’s most famous painting of the 1490s is The Last Supper, also painted in Milan. The painting represents the last meal shared by Jesus with his disciples before his capture and death. It shows specifically the moment when Jesus has said “one of you will betray me”. Leonardo tells the story of the consternation that this statement caused to the twelve followers of Jesus.

The novelist Matteo Bandello observed Leonardo at work and wrote that some days he would paint from dawn till dusk without stopping to eat, and then not paint for three or four days at a time. This, according to Vasari, was beyond the comprehension of the prior, who hounded him until Leonardo asked Ludovico to intervene. Vasari describes how Leonardo, troubled over his ability to adequately depict the faces of Christ and the traitor Judas, told the Duke that he might be obliged to use the prior as his model.

When finished, the painting was acclaimed as a masterpiece of design and characterization, but it deteriorated rapidly, so that within a hundred years it was described by one viewer as “completely ruined”. Leonardo, instead of using the reliable technique of fresco, had used tempera over a ground that was mainly gesso, resulting in a surface which was subject to mold and to flaking. Despite this, the painting has remained one of the most reproduced works of art, countless copies being made in every medium from carpets to cameos. 

Leonardo da Vinci

Self-portrait in red chalk, circa 1512 to 1515

Self-portrait in red chalk, circa 1512 to 1515

 

Birth name

Leonardo di Ser Piero

Born

April 15, 1452
Vinci, Florence, in present-day Italy

Died

May 2, 1519 (aged 67)
Amboise, Indre-et-Loire, in present-day France

Nationality

Italian

Field

Many and diverse fields of arts and Sciences 

Movement

High Renaissance

Works

Mona Lisa,The Vitruvian Man, The last Supper

 

Leonardo di ser Piero da Vinci, April 15, 1452 – May 2, 1519) was an Italian polymath, being a scientist, mathematician, engineer, inventor, anatomist, painter, sculptor, architect, botanist, musician and writer. Leonardo has often been described as the archetype of the “Renaissance man”, a man whose “unquenchable curiosity” was equaled only by his powers of invention. He is widely considered to be one of the greatest painters of all time and perhaps the most diversely talented person ever to have lived. Helen Gardner says “The scope and depth of his interests were without precedent…His mind and personality seems to us superhuman, the man himself mysterious and remote”.

Born as the illegitimate son of a notary, Piero da Vinci, and a peasant woman, Caterina, at Vinci in the region of Florence, Leonardo was educated in the studio of the renowned Florentine painter, Verrocehho. Much of his earlier working life was spent in the service of Ludovico il Moro in Milan. He later worked in Rome, Bologna and Venice and spent his last years in France, at the home awarded him by King François I.

Leonardo was and is renowned primarily as a painter. Two of his works, the Mona Lisa and The Last Supper, are the most famous; most reproduced and most parodied portrait and religious painting of all time, their fame approached only by Michelangelo’s Creation of Adam. Leonardo’s drawing of the Vitruvian Man is also regarded as a cultural icon, being reproduced on everything from the Euro to text books to t-shirts. Perhaps fifteen of his paintings survive the small number due to his constant, and frequently disastrous, experimentation with new techniques, and his chronic procrastination. Nevertheless, these few works, together with his notebooks, which contain drawings, scientific diagrams, and his thoughts on the nature of painting, comprise a contribution to later generations of artists only rivaled by that of his contemporary, Michelangelo.

Leonardo is revered for his technological ingenuity. He conceptualized a helicopter, a tank, concentrated solar power, a calculator, the double hull and outlined a rudimentary theory of plate tectonics. Relatively few of his designs were constructed or were even feasible during his lifetime, but some of his smaller inventions, such as an automated bobbin winder and a machine for testing the tensile strength of wire, entered the world of manufacturing unheralded. As a scientist, he greatly advanced the state of knowledge in the fields of anatomy, civil engineering, optics, and hydrodynamics.