The Dreamcast is a home video game console released by Sega on November 27, 1998 in Japan, September 9, 1999 in North America, October 14, 1999 in Europe. It was the first in the sixth generation of video game consoles, preceding Sony's PlayStation 2, Nintendo's GameCube and Microsoft's Xbox; the Dreamcast was Sega's final home console, marking the end of the company's 18 years in the console market. In contrast to the expensive hardware of the unsuccessful Sega Saturn, the Dreamcast was designed to reduce costs with "off-the-shelf" components, including a Hitachi SH-4 CPU and an NEC PowerVR2 GPU. Released in Japan to a subdued reception, the Dreamcast enjoyed a successful U. S. launch backed by a large marketing campaign, but interest in the system declined as Sony built hype for the upcoming PlayStation 2. Sales did not meet Sega's expectations despite several price cuts, the company continued to incur significant financial losses. After a change in leadership, Sega discontinued the Dreamcast on March 31, 2001, withdrawing from the console business and restructuring itself as a third-party publisher.

9.13 million Dreamcast units were sold worldwide. Although the Dreamcast had a short lifespan and limited third-party support, reviewers have considered the console ahead of its time, its library contains many games considered creative and innovative, including Crazy Taxi, Jet Set Radio and Shenmue, as well as high-quality ports from Sega's NAOMI arcade system board. The Dreamcast was the first console to include a built-in modem for internet support and online play. Released in 1988, the Sega Genesis was Sega's entry into the fourth generation of video game consoles. Selling 30.75 million units worldwide, the Genesis was the most successful console Sega released. The successor to the Genesis, the Sega Saturn, was released in Japan in 1994; the Saturn was a CD-ROM-based console that displayed both 2D and 3D computer graphics, but its complex dual-CPU architecture made it more difficult to program for than its chief competitor, the Sony PlayStation. Although the Saturn debuted before the PlayStation in both Japan and the United States, its surprise U.

S. launch—which came four months earlier than scheduled—was marred by a lack of distribution, which remained a continuing problem for the system. Moreover, Sega's early release was undermined by Sony's simultaneous announcement that the PlayStation would retail for US$299—compared to the Saturn's initial price of $399. Nintendo's long delay in releasing a competing 3D console and the damage done to Sega's reputation by poorly supported add-ons for the Genesis allowed Sony to establish a foothold in the market; the PlayStation was successful in the U. S. in part due to a massive advertising campaign and strong third-party support engendered by Sony's excellent development tools and liberal $10 licensing fee. Sony's success was further aided by a price war in which Sega lowered the price of the Saturn from $399 to $299 and from $299 to $199 in order to match the price of the PlayStation–even though Saturn hardware was more expensive to manufacture and the PlayStation enjoyed a larger software library.

Losses on the Saturn hardware contributed to Sega's financial problems, which saw the company's revenue decline between 1992 and 1995 as part of an industry-wide slowdown. Furthermore, Sega's focus on the Saturn over the Genesis prevented it from capitalizing on the continued strength of the 16-bit market. Due to long-standing disagreements with Sega of Japan, Sega of America CEO Tom Kalinske became less interested in his position. On July 16, 1996, Sega announced that Shoichiro Irimajiri had been appointed chairman and CEO of Sega of America, while Kalinske would be leaving Sega after September 30 of that year. Sega announced that Sega Enterprises cofounder David Rosen and Sega of Japan CEO Hayao Nakayama had resigned from their positions as chairman and co-chairman of Sega of America, though both men remained with the company. Bernie Stolar, a former executive at Sony Computer Entertainment of America, was named Sega of America's executive vice president in charge of product development and third-party relations.

Stolar did not support the Saturn due to his belief that the hardware was poorly designed and publicly announced at E3 1997 that "The Saturn is not our future." After the launch of the Nintendo 64, sales of the Saturn and Sega's 32-bit software were reduced. As of August 1997, Sony controlled 47 percent of the console market, Nintendo controlled 40 percent, Sega controlled only 12 percent. Neither price cuts nor high-profile games were proving helpful to the Saturn's success. Due to the Saturn's poor performance in North America, Sega of America laid off 60 of its 200 employees in the fall of 1997; as a result of the company's deteriorating financial situation, Nakayama resigned as president of Sega in January 1998 in favor of Irimajiri. Stolar would subsequently accede to become president of Sega of America. Following five years of declining profits, in the fiscal year ending March 31, 1998, Sega suffered its first parent and consolidated financial losses since its 1988 listing on the Tokyo Stock Exchange.

Due to a 54.8% decline in consumer product sales, the company reported a consolidated net loss of ¥35.6 billion. Shortly before announcing its financial losses, Sega revealed that it was discontinuing the Saturn in North America, with the goal of preparing for the launch of its successor; this decision left the Western market without Sega games for over one year. Rumors about the upcoming Dreamcast—spread by Sega itself—leaked to the public before the last Saturn games were released. As

Rufous-crowned sparrow

The rufous-crowned sparrow is a small American sparrow. This passerine is found across the Southwestern United States and much of the interior of Mexico, south to the transverse mountain range, to the Pacific coast to the southwest of the transverse range, its distribution is patchy, with populations being isolated from each other. Twelve subspecies are recognized, though up to eighteen have been suggested; this bird has a brown back with gray underparts. The crown is rufous, the face and supercilium are gray with a brown or rufous streak extending from each eye and a thick black malar streak; these sparrows feed on seeds in the winter and insects in the spring and summer. The birds are territorial, with males guarding their territory through song and displays. Flight is awkward for this species, they breed during spring. Two to five eggs are laid in the bird's nest, cup-shaped and well hidden. Adult sparrows are preyed upon by house cats and small raptors, while young may be taken by a range of mammals and reptiles.

They have been known to live for two months. Although the species has been classified as least concern, or unthreatened with extinction, some subspecies are threatened by habitat destruction and one may be extinct; this bird belongs to the family Passerellidae. The American sparrows are seed-eating New World birds with conical bills, brown or gray plumage, distinctive head patterns. Birds in the genus Aimophila tend to be medium-sized at 5 to 8 inches in length, live in arid scrubland, have long bills and tails in proportion to their body size as well as short, rounded wings, build cup-shaped nests; the rufous-crowned sparrow was described in 1852 by American ornithologist John Cassin as Ammodramus ruficeps. It has been described as belonging to the genus Peucaea, which contains several sparrows in the genus Aimophila that share characteristics, such as a larger bill and a patch of yellow under the bend of the wing, that other members of the genus do not. However, splitting the Peucaea sparrows into a separate genus is not recognized.

A 2008 phylogenetic analysis of the genus Aimophila divided it into four genera, with the rufous-crowned sparrow and its two closest relatives, the Oaxaca sparrow and rusty sparrow, being maintained as the genus Aimophila. In addition, this study suggested that the rufous-crowned sparrow may be more related to the brown towhees of the genus Pipilo than the other members of the historical genus Aimophila; the derivation of the current genus name, Aimophila, is from the Greek aimos/ἀιμος, meaning "thicket", -philos/-φιλος, meaning "loving". The specific epithet is a literal derivation of the common name, derived from the Latin rufus, meaning "reddish" or "tawny", -ceps, from caput, meaning "head"; the bird is occasionally referred to colloquially as the rock sparrow because of its preference for rocky slopes. Twelve subspecies are recognized, although sometimes up to eighteen are named. A. r. ruficeps, the nominate subspecies, was described by Cassin in 1852. It is found on the western slopes of the Sierra Nevada.

This subspecies is darker and noticeably smaller than A. r. eremoeca and has distinct rufous-brown streaking on its upperparts. A. r. canescens was described by American ornithologist W. E. Clyde Todd in 1922, it is found in southwestern California and northeast Baja California as far east as the base of the San Pedro Mártir. While the species itself is listed as of least concern, this subspecies is listed as a "species of special concern" by the California Department of Fish and Wildlife, signifying that this population is threatened with extinction, it appears to be similar to A. r. ruficeps but is darker. A. r. obscura, described by Donald R. Dickey and Adriaan van Rossem in 1923, is found in the Channel Islands of California on Santa Cruz, on Santa Catalina. While the Santa Catalina population has not been observed since 1863, the subspecies seems to have colonized Anacapa Island. No records exist of them before 1940; this subspecies is darker. A. r. sanctorum was described by van Rossem in 1947.

It was found on the Todos Santos Islands off the coast of northwest Baja California. This subspecies is believed to be extinct; this is the darkest of the coastal subspecies on its underbelly. A. r. sororia was described by Robert Ridgway in 1898, is found in the mountains of southern Baja California the Sierra de la Laguna. It is the palest of the coastal subspecies. A. r. scottii, described by George Sennett in 1888, is found from northern Arizona to New Mexico south to northeastern Sonora and northwestern Coahuila. It appears to be a darker gray than A. r. eremoeca and has narrower and darker rufous streaks on its breast. A. r. rupicola was described by van Rossem in 1946. It is found in the mountains of southwestern Arizona, it is darker and grayer on its back. A. r. simulans was described by van Rossem in 1934, it is found in northwestern Mexico from southeastern Sonora and southwestern Chihuahua to Nayarit and northern Jalisco. It is paler on its underbelly than A. r. scottii. A. r. eremoeca was described by N. C. Brown in 1882.

It is found from southeastern Colorado to New Mexico, northern Chihuahua, central Coahuila. It has a dark breast. A. r. fusca, described by Edward William Nelson in 1897, is found in western Mexico from southern Nayarit to southwestern Jalisco, northern Co

Advanced Materials

Advanced Materials is a weekly peer-reviewed scientific journal covering materials science. It includes communications and feature articles on topics in chemistry, nanotechnology, ceramics and biomaterials. According to the Journal Citation Reports, the journal has a 2018 impact factor of 25.809. The journal was established in 1988 as a supplement to the general chemistry journal Angewandte Chemie and remained part of that journal for the first 18 months of its existence; the founding editor-in-chief was Peter Goelitz. The current editor-in-chief is Peter Gregory; the journal appeared monthly. Since 2009 it has been published weekly, with 48 issues per year; as the volume of research in materials science increased since the 1990s, several journals were spun off, including: Advanced Engineering Materials, 1999 Advanced Functional Materials, 2001 Small, 2005 Advanced Energy Materials, 2011 Advanced Healthcare Materials, 2012 Advanced Optical Materials, 2013 Advanced Materials Interfaces, 2014 Advanced Electronic Materials, 2015 Advanced Materials Technologies, 2016 Small Methods, 2017 Solar RRL, 2017 Official website