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This guide to China enables you to explore the sights and attractions of the country, offers advice on where to stay and eat, and comments on China's history, politics, environment, and people.

This book is the first published English-language translation of the significant History of Islamic Spain by Ibn al-Qutiya (d. Cordova 367 / 977). Including extensive notes and comments, a genealogical table and relevant maps, the text is preceded by a study of the author and his work, and is the only serious examination of the unique manuscript since Pascual de Gayangos' edition in 1868. Ibn al-Qutiya's work is one of the significant and earliest histories of Muslim Spain and an important source for scholars. Although like most Muslims of al-Andalus in this period, Ibn al-Qutiya was of European origin, he was a loyal servant of the Iberian Umayyads, and taught Arabic, traditions (hadith) and history in the Great Mosque of Cordova. Written at the height of the Umayyad Caliphate of Muslim Spain and Portugal (al-Andalus), the History describes the first 250 years of Muslim rule in the peninsula. The text, first fully translated into Spanish in 1926, deals with all aspects of life, and includes accounts of Christians, Jews and Muslim converts. This book will be of great interest to scholars and students of the history of Spain and Portugal, Islamic history, and Mediaeval European history.

The benthic infaunal macroinvertebrate communities of Hog Island Bay of the Virginia Eastern Shore were quantitatively sampled at 30 locations on August 31 and September 1, 1995. The primary objectives of this study were: (1) to characterize the subtidal macroinfaunal benthic communities of Hog Island Bay, (2) to examine relationships between abiotic factors and the macroinfaunal communities and (3) to characterize the environmental condition of the system using the Benthic Index of Biotic Integrity (B-IBI) (Weisburg et al. 1997) and the EMAP Benthic Index for the Virginian Province (Strobel et al. 1995). The ecological condition of Hog Island Bay appears to be largely defined by its geographic location and physical processes acting along a coastal zone. Multivariate statistical analyses reveal a community spatial pattern not unlike other temperate estuaries. Outside of a sharp community transition existing in the vicinity of Great Machipongo Inlet, benthic assemblages throughout the study area generally exhibit subtle boundaries and a high degree of internal similarity. When compared among other estuaries and bays in the Virginian Province, community attributes measured for Hog Island Bay were most similar to polyhaline reaches of Chesapeake Bay. Also, both physical and biological data imply that the structure of Virginia's polyhaline benthic communities is different from that occurring in communities north of Virginia. In terms of both the B-IBI and the EMAP index, the benthic community condition of Hog Island Bay may be viewed as exceptional when compared with other systems occurring throughout the Virginian Province.

Mycorrhizal fungi play a critical role in nutrient uptake by most tree species, and the importance of this function in regulating the outcome of increasing atmospheric CO$\\sb2$ on natural ecosystems is widely assumed. However, few studies have considered whether the presence or absence of mycorrhizae differentially affects the response of nutrient-limited host trees to elevated CO$\\sb2.$ Understanding the integration of leaf-level, root-level and whole-plant processes is crucial to predicting the influence of mycorrhizal fungi on the response of host trees to elevated CO$\\sb2$ across a range of environments. I manipulated mycorrhizal status and phosphorus supply in a phytotron to investigate the role of the mycorrhizal fungus Pisolithus tinctorius (D. Marx isolate #306) in the response of loblolly pine seedlings to elevated CO$\\sb2$ under different phosphorus regimes. Monthly measurements of biomass accumulation and allocation, relative growth rates and needle characteristics were used to examine whole-plant responses. Effects on root-level processes were examined by comparing root nutrient and carbohydrate concentrations with the extent of mycorrhizal colonization. Photosynthesis and non-destructive measurements of rubisco activity and ribulose 1,5-bisphosphate regeneration capacity were used to examine effects on leaf-level processes. Linkages among photosynthetic processes were examined using covariate analysis and used to infer photosynthetic regulation by the rate of carbohydrate utilization. Mycorrhizal colonization significantly increased phosphorus uptake and growth of phosphorus-limited seedlings, but did not affect the response of seedling photosynthesis or biomass to elevated CO$\\sb2.$ In fact, phosphorus-limited seedlings showed the greatest relative responses to elevated CO$\\sb2,$ apparently as a result of increased phosphorus uptake and increased phosphorus use efficiency. Additionally, elevated CO$\\sb2$ did not differentially affect seedlings grown from seeds obtained from Florida and coastal North Carolina populations. However, elevated CO$\\sb2$ reduced photosynthetic capacity and tissue phosphorus concentrations in seedlings supplied with phosphorus at levels adequate for maximum seedling growth in ambient CO$\\sb2.$ These results suggest that phosphorus-limited loblolly pine seedlings initially will respond to elevated CO$\\sb2$ due to increases in phosphorus uptake and phosphorus use efficiency, but ultimately phosphorus-limitation will reduce or eliminate the fertilization effect of elevated CO$\\sb2.$

The transmission of controlled, forced acoustic signals through human lung airway systems was studied as a possible new diagnostic technique. Two novel systems were developed to introduce controlled acoustic signals at the mouth and detect the transmitted signals on the thoracic surface. An acoustic spectrometer system delivers step-wise incremented pure tones and indicates the transmitted signal amplitude and phase responses. A noise correlator system delivers wide-band random noise and correlates the transmitted signals to yield the impulse response of the lungs. Clinical applications of both systems established the viability of using acoustic transmission as a diagnostic tool. The noise correlator system indicates the most readily transmitted frequencies. The correlograms obtained from all subjects indicate strong sound transmission at about 650 Hz. Almost all records for healthy, non-smoking subjects also indicate strong transmission at about 2500 Hz, whereas records for asymptomatic, smoking subjects rarely indicate strong transmission at this frequency. These findings suggest that acoustic probing is sensitive to airway changes undetectable by standard pulmonary function tests. The theoretical resonances of the human airway system were estimated by solving linearized, one-dimensional fluid dynamic equations for steady-oscillatory flow in an asymmetric, dendritic model-structure of liquid-lined tubes. The calculations indicate that the lower frequency resonance is determined by the characteristics of the trachea and mainstem bronchi. These airways are minimally affected in disease which explains why this resonance is common to all of the clinical records. The calculations also indicate that the characteristics of the mucus-lined middle-generation airways determine the higher frequency resonance. An increase in mucus layer thickness, as occurs in the lungs of smokers, dampens transmission and explains, to some extent, the common absence of the higher frequency resonance in the records of smoking subjects. Altogether, acoustic scanning has been shown to be a viable method for clinical evaluation of the lungs. It offers a safe, effective, and sensitive means for early detection of airway disease.