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The Volga Delta developed in the closed Caspian basin can be classified as a river-dominated type. The subaqueous part of the delta (avandelta) is characterized by an extremely gentle slope and may be subdivided into shallow and deep parts. The very low-angle slope of the shallow avandelta is a major factor to mitigate impacts of Caspian sea-level (CSL) changes on the Volga Delta during the last 100 years. The CSL has fluctuated 3.46 m in the last 100 years, with a high of -25.55 m relative to the Baku Datum (BD) in 1903 and a low of -29.01 m BD in 1977. Sea-level changes can be grouped into three stages: (1) slowly falling at an average rate of 1.1 cm yr-1 in 1900–1929; (2) rapidly falling at an average rate of 6.3 cm yr-1 in 1930–1977; (3) rapidly rising at an average rate of 8.8 cm yr-1 in 1978–1999. During the rapid fall stage of sea level, the Volga delta-plain expanded at a rate of 2.3 km2yr-1 to 180 km2yr-1 because of alluvial accumulation and exposure of the shallow avandelta. Flourishing subaqueous vegetation promotes this expansion by trapping suspended sediments on the avandelta. The shallow avandelta is primarily covered by freshwater and its geomorphic and sedimentary features are controlled more by the river flow than by the CSL changes, waves or wind-induced currents. The shallow avandelta decelerated delta progradation during sea-level fall and delayed delta retreat during sea-level rise. Significant changes in the delta-plain area have not occurred in the rapid CSL rise stage. Moreover, the distributaries and their distal underwater channels underwent erosion by the river flow at least until the end of the last century. The CSL has risen with an average annual rate of 8.8 cm during the last 20 years, yet coastal erosion, coastal flooding, wetland loss and saltwater intrusion, observed in other deltas, have not occurred here. This may have resulted from the existence of the shallow avandelta and show that the world's deltas respond to sea-level rise in different ways. [ABSTRACT FROM AUTHOR]

Cancer is one of the major non-communicable diseases posing a threat to world health. Unfortunately, improvements in socioeconomic conditions are usually associated with increased cancer incidence. In this Commission, we focus on China, India, and Russia, which share rapidly rising cancer incidence and have cancer mortality rates that are nearly twice as high as in the UK or the USA, vast geographies, growing economies, ageing populations, increasingly westernised lifestyles, relatively disenfranchised subpopulations, serious contamination of the environment, and uncontrolled cancer-causing communicable infections. We describe the overall state of health and cancer control in each country and additional specific issues for consideration: for China, access to care, contamination of the environment, and cancer fatalism and traditional medicine; for India, affordability of care, provision of adequate health personnel, and sociocultural barriers to cancer control; and for Russia, monitoring of the burden of cancer, societal attitudes towards cancer prevention, effects of inequitable treatment and access to medicine, and a need for improved international engagement., (Copyright © 2014 Elsevier Ltd. All rights reserved.)