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The most important recent findings disclose that HDL is more complex than previously thought. HDL subclasses differ in physical-chemical properties, protein and lipid composition, metabolism, physiological functions and pathophysiological significance. The staggering complexity of HDL demands significantly more investigation before we can truly begin to understand HDL metabolism and function in humans.

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1. In a unique phenomenon restricted to the ever wet forests of Southeast Asia, hundreds of species from dozens of plant families reproduce synchronously at irregular, multi-year intervals. The proximate environmental cues that synchronize these general flowering events have not been evaluated systematically because there have been no long-term, high temporal resolution, species-level records from the region.2. We present 13 years of weekly flowering records for five Shorea species as well as daily temperature and rainfall records from the Pasoh Forest Reserve, Peninsular Malaysia. We constructed models to evaluate hypothesized relationships between flowering and cool temperature, drought, and additive and synergistic effects of cool temperature and drought for each species. Model parameters include periods of time for floral cue accumulation and flower development and temperature and/ or rainfall thresholds required for floral initiation. Parameters estimated using flowering observations from 2001 to 2011 were used to forecast flowering for 2011-2014. 3. We show that drought and cool temperatures acting synergistically best explain the timing of flowering events for all Shorea species in the section Mutica and forecast the largest general flowering event accurately. Periods estimated for signal accumulation ranged from 54 to 90 days among species. Periods estimated for flowers to develop ranged between 43 and 96 days and closely followed the interspecific sequence of flowering in the Shorea species. Drought and temperature thresholds also varied among species, with Shorea maxwelliana requiring the most severe drought and Shorea leprosula the lowest temperatures. 4. Synthesis. Our results indicate that cool temperatures and low rainfall occurring on seasonal time-scales of about 2-3 months rather than brief cold snaps or brief droughts best explain general flowering in Shorea species at the Pasoh | 587 Journal of Ecology CHEN Et al.

The mechanism of general flowering in Dipterocarpaceae in the Malay Peninsula is revealed through field survey and meteorological data analyses. The regions of general flowering coincide with those which experienced a low night-time temperature (LNT) c. 2 mo before flowering. This supports the hypothesis that low air temperature induces the development of floral buds of dipterocarps. LNT was found to be caused by radiative cooling during dry spells in winter when the northern subtropical ridge (STR) occasionally migrates southwards with a dry air mass into the equatorial region. LNT events usually occur in La Niña episodes, not in El Niño episodes as believed previously. This is because the southward migration of the STR is associated with the intensification of local meridional Hadley Circulation in the western Pacific, which is strengthened in a La Niña episode. Results suggest that El Niño-like climate change in increased atmospheric carbon dioxide concentrations may be critical for the tropical rain forest biome in south-east Asia.

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The oxygen isotope enrichment of bulk leaf water (D b ) was measured in cotton (Gossypium hirsutum) leaves to test the CraigGordon and Farquhar-Gan models under different environmental conditions. D b increased with increasing leaf-to-air vapor pressure difference (VPd) as an overall result of the responses to the ratio of ambient to intercellular vapor pressures (e a /e i ) and to stomatal conductance (g s ). The oxygen isotope enrichment of lamina water relative to source water ð D 1 Þ; which increased with increasing VPd, was estimated by mass balance between less enriched water in primary veins and enriched water in the leaf. Recently, the analysis of the oxygen isotope composition (d 18 O) of leaf water became of increased interest as a result of efforts to obtain information on the global carbon cycle Gillon and Yakir, 2001) and because of applications in agriculture (Barbour et al., 2000a). These and other applications were recently updated (Barbour, 2007;Farquhar et al., 2007). The d 18O of atmospheric CO 2 and of plant organic matter depends strongly on the extent of leaf water enrichment that occurs during transpiration (Barbour et al., 2000b) because the diffusivity and vapor pressure of heavier H 2 18O are less than that of lighter H 2 16 O (Craig and Gordon, 1965). A large portion of the CO 2 that enters the leaf equilibrates with evaporatively enriched leaf water via the catalytic activity of carbonic anhydrase, then retrodiffuses out of the leaf, increasing the d