Chimera (mythology)

The Chimera according to Greek mythology, was a monstrous fire-breathing hybrid creature of Lycia in Asia Minor, composed of the parts of more than one animal. It is depicted as a lion, with the head of a goat protruding from its back, a tail that might end with a snake's head, it was one of the offspring of Typhon and Echidna and a sibling of such monsters as Cerberus and the Lernaean Hydra. The term "chimera" has come to describe any mythical or fictional creature with parts taken from various animals, to describe anything composed of disparate parts, or perceived as wildly imaginative, implausible, or dazzling. Homer's brief description in the Iliad is the earliest surviving literary reference: "a thing of immortal make, not human, lion-fronted and snake behind, a goat in the middle, snorting out the breath of the terrible flame of bright fire." Elsewhere in the Iliad, Homer attributes the rearing of Chimera to Amisodorus. Hesiod's Theogony follows the Homeric description: he makes the Chimera the issue of Echidna: "She was the mother of Chimaera who breathed raging fire, a creature fearful, swift-footed and strong, who had three heads, one of a grim-eyed lion.

Her did Pegasus and noble Bellerophon slay." The author of the Bibliotheca concurs: Descriptions agree that she breathed fire. The Chimera is considered to have been female despite the mane adorning her head, the inclusion of a close mane was depicted on lionesses, but the ears were always visible. While there are different genealogies, in one version the Chimera mated with her brother Orthrus and was the mother of the Sphinx and the Nemean lion; the Chimera was defeated by Bellerophon with the help of Pegasus, at the command of King Iobates of Lycia, after terrorizing Lycia and nearby lands. Since Pegasus could fly, Bellerophon shot the Chimera from the air, safe from her heads and breath. A scholiast to Homer adds that he finished her off by equipping his spear with a lump of lead that melted when exposed to the Chimera's fiery breath and killed her, an image drawn from metalworking. Robert Graves suggests, "The Chimera was a calendar-symbol of the tripartite year, of which the seasonal emblems were lion and serpent."

The Chimera was situated in foreign Lycia. An autonomous tradition, one that did not rely on the written word, was represented in the visual repertory of the Greek vase-painters; the Chimera first appears at an early stage in the repertory of the proto-Corinthian pottery-painters, providing some of the earliest identifiable mythological scenes that may be recognized in Greek art. The Corinthian type is fixed, after some early hesitation, in the 670s BC; the fascination with the monstrous devolved by the end of the seventh century into a decorative Chimera-motif in Corinth, while the motif of Bellerophon on Pegasus took on a separate existence alone. A separate Attic tradition, where the goats breathe fire and the animal's rear is serpentine, begins with such confidence that Marilyn Low Schmitt is convinced there must be unrecognized or undiscovered local precursors. Two vase-painters employed the motif so they are given the pseudonyms the Bellerophon Painter and the Chimaera Painter. A fire-breathing lioness was one of the earliest of solar and war deities in Ancient Egypt and influences are feasible.

The lioness represented the war goddess and protector of both cultures that would unite as Ancient Egypt. Sekhmet was one of the dominant deities in upper Bast in lower Egypt; as divine mother, more as protector, for Lower Egypt, Bast became associated with Wadjet, the patron goddess of Lower Egypt. In Etruscan civilization, the Chimera appears in the Orientalizing period that precedes Etruscan Archaic art; the Chimera appears in Etruscan wall-paintings of the fourth century BC. In Indus civilization are pictures of the chimera in many seals. There are different kinds of the chimera composed of animals from the Indian subcontinent, it is not known. In Medieval art, although the Chimera of antiquity was forgotten, chimerical figures appear as embodiments of the deceptive satanic forces of raw nature. Provided with a human face and a scaly tail, as in Dante's vision of Geryon in Inferno xvii.7–17, 25–27, hybrid monsters, more akin to the Manticore of Pliny's Natural History, provided iconic representations of hypocrisy and fraud well into the seventeenth century, through an emblematic representation in Cesare Ripa's Iconologia.

The myths of the Chimera may be found in the Bibliotheca of Pseudo-Apollodorus, the Iliad by Homer, the Fabulae 57 and 151 by Hyginus, the Metamorphoses, the Theogony 319ff by Hesiod. Virgil, in the Aeneid employs Chimaera for the name of a gigantic ship of Gyas in the ship-race, with possible allegorical significance in contemporary Roman politics. Pliny the Elder cited Ctesias and quoted Photius identifying the Chimera with an area of permanent gas vents that still may be found by hikers on the Lycian Way in southwest Turkey. Called in Turkish, Yanartaş, the area contains some two dozen vents in the ground, grouped in two patches on the hill

Pyramidella panamensis

Pyramidella panamensis is a species of sea snail, a marine gastropod mollusk in the family Pyramidellidae, the pyrams and their allies. The slender shell has an elongate-conic shape, its color is horn-yellow, excepting the body whorl, suffused with, pale rose-purple. Its length measures 8.8 mm. The 2½ whorls of the protoconch are small and form a depressed helicoid spire, whose axis is at right angles to that of the succeeding turns, in the first of which it is a little more than half immersed; the twelve whorls of the teleoconch are flattened. They are flatly shouldered at the summit, crenulated and decidedly channeled at the periphery, they are marked on the posterior half by feeble riblets which disappear before reaching the middle of the whorl. The sutures are channeled; the periphery of the body whorl has a deep sulcus, crossed by numerous slender and spaced axial riblets. The base of the shell is well rounded, with a strong fasciole about the columella; the aperture is oval. The posterior angle is acute, channeled anteriorly.

The outer lip is thin. The columella is slender, revolute, it is provided with a lamellar posterior fold at the insertion of the columella, two slender oblique ones anterior to it. This marine species occurs in the Pacific Ocean off Panama Bay. To USNM Invertebrate Zoology Mollusca Collection To World Register of Marine Species


SiGe, or silicon-germanium, is an alloy with any molar ratio of silicon and germanium, i.e. with a molecular formula of the form Si1−xGex. It is used as a semiconductor material in integrated circuits for heterojunction bipolar transistors or as a strain-inducing layer for CMOS transistors. IBM introduced the technology into mainstream manufacturing in 1989; this new technology offers opportunities in mixed-signal circuit and analog circuit IC design and manufacture. SiGe is used as a thermoelectric material for high temperature applications; the use of silicon-germanium as a semiconductor was championed by Bernie Meyerson. SiGe is manufactured on silicon wafers using conventional silicon processing toolsets. SiGe processes achieve costs similar to those of silicon CMOS manufacturing and are lower than those of other heterojunction technologies such as gallium arsenide. Organogermanium precursors have been examined as less hazardous liquid alternatives to germane for MOVPE deposition of Ge-containing films such as high purity Ge, SiGe, strained silicon.

SiGe foundry services are offered by several semiconductor technology companies. AMD disclosed a joint development with IBM for a SiGe stressed-silicon technology, targeting the 65-nm process. TSMC sells SiGe manufacturing capacity. In July 2015, IBM announced that it had created working samples of transistors using a 7 nm silicon-germanium process, promising a quadrupling in the amount of transistors compared to a contemporary process. SiGe allows CMOS logic to be integrated with heterojunction bipolar transistors, making it suitable for mixed-signal circuits. Heterojunction bipolar transistors have higher forward gain and lower reverse gain than traditional homojunction bipolar transistors; this translates into high frequency performance. Being a heterojunction technology with an adjustable band gap, the SiGe offers the opportunity for more flexible band gap tuning than silicon-only technology. Silicon Germanium-on-insulator is a technology analogous to the Silicon-On-Insulator technology employed in computer chips.

SGOI increases the speed of the transistors inside microchips by straining the crystal lattice under the MOS transistor gate, resulting in improved electron mobility and higher drive currents. SiGe MOSFETs can provide lower junction leakage due to the lower band gap value of SiGe. However, a major issue with SGOI MOSFETs is the inability to form stable oxides with silicon germanium using standard silicon oxidation processing. A silicon germanium thermoelectric device, MHW-RTG3, was used in the Voyager 2 spacecraft. Silicon germanium thermoelectric devices were used in other MHW-RTGs and GPHS-RTGs aboard Cassini, Galileo and Flight Units F-1 and F-4. Low-κ dielectric Silicon on insulator Silicon-tin Application of silicon-germanium thermoelectrics in space exploration Raminderpal Singh. Silicon Germanium: Technology and Design. IEEE Press / John Sons. ISBN 978-0-471-66091-0. John D. Cressler. Circuits and Applications Using Silicon Heterostructure Devices. CRC Press. ISBN 978-1-4200-6695-1. Ge Precursors for Strained Si and Compound Semiconductors.