Tropical peatlands, which coexist with swamp forests, have accumulated vast amounts of carbon as soil organic matter. Since the 1970s, however, deforestation and drainage have progressed on an enormous scale. In addition, El Niñ o and Southern Oscillation (ENSO) drought and large-scale fires, which grow larger under the drought condition, are accelerating peatland devastation. That devastation enhances decomposition of soil organic matter and increases the carbon release to the atmosphere as CO 2 . This phenomenon suggests that tropical peatlands have already become a large CO 2 source, but related quantitative information is limited. Therefore, we evaluated the CO 2 balance of a tropical peat swamp forest in Central Kalimantan, Indonesia, using 3 years of CO 2 fluxes measured using the eddy covariance technique from 2002 through 2004. The forest was disturbed by drainage; consequently, groundwater level (GL) was reduced. The net ecosystem CO 2 production (NEP) measurements showed seasonal variation, which was slightly positive or almost zero in the early dry season, and most-negative late in the dry season or early the rainy season. This seasonality is attributable to the seasonal pattern of climate, tree phenology and fires. Slightly positive NEP resulted from smaller ecosystem respiration (RE) and larger gross primary production (GPP) under conditions of high photosynthetic photon flux density (PPFD) and large leaf area index (LAI). The mostnegative NEP resulted from smaller GPP and larger RE. The smaller GPP was related to high vapor pressure deficit (VPD), small LAI and low PPFD because of smoke from fires. The larger RE was related to low GL. Annual NEP values were estimated respectively as À602, À382 and À313 g C m À2 yr À1 for 2002, 2003 and 2004. These negative NEP values show that the tropical peat swamp forest, disturbed by drainage, functioned as a CO 2 source. That source intensity was highest in 2002, an ENSO year, mainly because of low PPFD caused by dense smoke emitted from large fires.

LRR-containing proteins are present in over 2000 proteins from viruses to eukaryotes. Most LRRs are 20-30 amino acids long, and the repeat number ranges from 2 to 42. The known structures of 14 LRR proteins, each containing 4-17 repeats, have revealed that the LRR domains fold into a horseshoe (or arc) shape with a parallel beta-sheet on the concave face and with various secondary structures, including alpha-helix, 3(10)-helix, and pII helix on the convex face. We developed simple methods to charactere quantitatively the arc shape of LRR and then applied them to all known LRR proteins. A quantity of 2Rsin(phi/2), in which R and phi are the radii of the LRR arc and the rotation angle about the central axis per repeating unit, respectively, is highly conserved in all the LRR proteins regardless of a large variety of repeat number and the radius of the LRR arc. The radii of the LRR arc with beta-alpha structural units are smaller than those with beta-3(10) or beta-pII units. The concave face of the LRR beta-sheet forms a surface analogous to a part of a Möbius strip.

In Southeast Asia, peatland is widely distributed and has accumulated a massive amount of soil carbon, coexisting with peat swamp forest (PSF). The peatland, however, has been rapidly degraded by deforestation, fires, and drainage for the last two decades. Such disturbances change hydrological conditions, typically groundwater level (GWL), and accelerate oxidative peat decomposition. Evapotranspiration (ET) is a major determinant of GWL, whereas information on the ET of PSF is limited. Therefore, we measured ET using the eddy covariance technique for 4-6 years between 2002 and 2009, including El Niño and La Niña events, at three sites in Central Kalimantan, Indonesia. The sites were different in disturbance degree: a PSF with little drainage (UF), a heavily drained PSF (DF), and a drained burnt ex-PSF (DB); GWL was significantly lowered at DF, especially in the dry season. The ET showed a clear seasonal variation with a peak in the mid-dry season and a large decrease in the late dry season, mainly following seasonal variation in net radiation (Rn ). The Rn drastically decreased with dense smoke from peat fires in the late dry season. Annual ET forced to close energy balance for 4 years was 1636 ± 53, 1553 ± 117, and 1374 ± 75 mm yr(-1) (mean ± 1 standard deviation), respectively, at UF, DF, and DB. The undrained PSF (UF) had high and rather stable annual ET, independently of El Niño and La Niña events, in comparison with other tropical rainforests. The minimum monthly-mean GWL explained 80% of interannual variation in ET for the forest sites (UF and DF); the positive relationship between ET and GWL indicates that drainage by a canal decreased ET at DF through lowering GWL. In addition, ET was decreased by 16% at DB in comparison with UF chiefly because of vegetation loss through fires.

A number of human diseases have been shown to be associated with mutation in the genes encoding leucine-rich-repeat (LRR)-containing proteins. They include 16 different LRR proteins. Mutations of these proteins are associated with 19 human diseases. The mutations occur frequently within the LRR domains as well as their neighboring domains, including cysteine clusters. Here, based on the sequence analysis of the LRR domains and the known structure of LRR proteins, we describe some features of different sequence variants and discuss their adverse effects. The mutations in the cysteine clusters, which preclude the formation of sulfide bridges or lead to a wrong paring of cysteines in extracellular proteins or extracellular domains, occur with high frequency. In contrast, missense mutations at some specific positions in LRRs are very rare or are not observed at all.

The 3(10)-helix is characterized by having at least two consecutive hydrogen bonds between the main-chain carbonyl oxygen of residue i and the main-chain amide hydrogen of residue i + 3. The helical parameters--pitch, residues per turn, radius, and root mean square deviation (rmsd) from the best-fit helix--were determined by using the HELFIT program. All 3(10)-helices were classified as regular or irregular based on rmsd/(N - 1)1/2 where N is the helix length. For both there are systematic, position-specific shifts in the backbone dihedral angles. The average phi, psi shift systematically from approximately -58 degrees, approximately -32 degrees to approximately -90 degrees, approximately -4 degrees for helices 5, 6, and 7 residues long. The same general pattern is seen for helices, N = 8 and 9; however, in N = 9, the trend is repeated with residues 6, 7, and 8 approximately repeating the phi, psi of residues 2, 3, and 4. The residues per turn and radius of regular 3(10)-helices decrease with increasing length of helix, while the helix pitch and rise per residue increase. That is, regular 3(10)-helices become thinner and longer as N increases from 5 to 8. The fraction of regular 3(10)-helices decreases linearly with helix length. All longer helices, N > or = 9 are irregular. Energy minimizations show that regular helices become less stable with increasing helix length. These findings indicate that the definition of 3(10)-helices in terms of average, uniform dihedral angles is not appropriate and that it is inherently unstable for a polypeptide to form an extended, regular 3(10)-helix. The 3(10)-helices observed in proteins are better referred to parahelices.