In their monumental work "The Cactaceae", BRITTON and ROSE (I9) record 1235 species belonging to the three tribes which constitute the family of the Cacti. The actual number of the species must be con- siderably higher. Cacti occur frequently in tlie more arid and less accessible regions of the American Continent, nearly always within very narrow and definite borderlines. The habitat of a species is in many instances a single valley located in a remote, uninhabited region of the Cordillera. Thus the collection of flowering specimens fit for botanical identification is some- times extremely difficult. On the other hand, cacti are apt to develop individual variations in their characteristic morphological features, rendering the definition of a species difficult and often illusory. Specimens taken from their normal habitat to botanical gardens or arboreta often die, degenerate or stop flowering. Taking into account all these difficulties, it is not surprising to find considerable differences of opinion among botanists on the taxonomy of the cactaceae. A considerable number of species have not been well defined and in many cases different names have been given to the same species. The index of BRITTON and ROSE records not less than 7000 binomials.

During the early 1950's there appeared reports, from time to time of the presence among the products elaborated by actinomycetes of antifungal antibiotics which exhibited very similar and very characteristic multipeaked ultraviolet absorption spectra. In 1954, with a good number of examples on record, these spectra were analyzed and identified as those of straight-chain conjugated polyenes, comprising tetraenes, pentaenes, hexaenes and heptaenes (85, I30). These antibiotics have since been commonly referred to as the polyene antifungal antibiotics to distinguish them from a host of other miscellaneous antibiotics which also have antifungal properties. Within the next few years, reports of discoveries of new members of this class multiplied rapidly, and almost sixty are now known. Unquestionably, a number of these will eventually be found to be identical with others, as has already happened in several instances: for example, the tetraene "tennecetin" proved to be a rediscovery of pimaricin (34), and in the methyl- pentaenes "moldcidin E" has been identified with pentamycin (83), and "lagosin" appears to be indistinguishable from fungichromin (22). Those that have been purified have turned out to be of fairly high molecular weight (ca. 700-1300) and all appear to be substances of rather similar molecular structure. So far only three, pimaricin, fungi- chromin (lagosin) and filipin, have been structurally elucidated.

1946 Chicago is filled with trouble; gangsters, thieves, cut throats, dirty dealers & femme fatales. The people of the city have problems, private detective Shamus Elias Stone fixes them, for a price . . . A simple seeming case of a missing actress leads to a tangled maze, as a masked killer takes his revenge. The killer wears the mask of the villainous robots of "Cowboy Robo," Shamus Stone suspects that the popular serial is at the center of this case

Based off his journal entries that he been written since he was young, Taysean Davis is telling a story about him, his step brother, 4 of his cousins plus 5 of his best friends had the wildest summer that he never soon forget and changing everybody life. He just got hired on full-time at Cashville the Mag as a journalist after doing his internship earlier that summer. Between the all parties, and the get togethers, comes the drama that he's experience. The 615 Story will take you on a journey where Taysean and his people has gone through and explain how's life is really like in their hometown of Nashville Tennessee.

Computer networks dramatically impact the Air Force mission and day-to-day operations. As network speeds increase to the gigabit range and beyond, better means for arbitrating network access becomes critical for increasing performance. Conventional approaches to increase Ethernet performance include using higher bandwidth media such as fiber optic cabling. However, there is a limit to the increase of effectiveness these measures provide. Spread spectrum multiple access techniques allow multiple users to simultaneously access the shared network resources through the use of special coding. These techniques have been principally employed in wireless networking environments to compensate for the scarce bandwidth inherent in the systems. Since cabling infrastructure upgrades may not be a viable option for increasing network performance, we apply spread spectrum techniques to a wired local area network to increase throughput and lower delay.

This title is part of UC Press's Voices Revived program, which commemorates University of California Press’s mission to seek out and cultivate the brightest minds and give them voice, reach, and impact. Drawing on a backlist dating to 1893, Voices Revived makes high-quality, peer-reviewed scholarship accessible once again using print-on-demand technology. This title was originally published in 1933.

This title is part of UC Press's Voices Revived program, which commemorates University of California Press’s mission to seek out and cultivate the brightest minds and give them voice, reach, and impact. Drawing on a backlist dating to 1893, Voices Revived makes high-quality, peer-reviewed scholarship accessible once again using print-on-demand technology. This title was originally published in 1933.