We report the observation of periodic 180 degrees stripe domains below the ferroelectric transition in thin films. Epitaxial PbTiO3 films of thickness d=1.6 to 42 nm on SrTiO3 substrates were studied using x-ray scattering. Upon cooling below T(C), satellites appeared around Bragg peaks indicating the presence of 180 degrees stripe domains of period Lambda=3.7 to 24 nm. The dependence of Lambda on d agrees well with theory including epitaxial strain effects, while the suppression of T(C) for thinner films is significantly larger than that expected solely from stripe domains.

Phenotypic plasticity in overcoming heat stress-induced damage across hot tropical rice-growing regions is predominantly governed by relative humidity. Expression of transpiration cooling, an effective heat-avoiding mechanism, will diminish with the transition from fully flooded paddies to water-saving technologies, such as direct-seeded and aerobic rice cultivation, thus further aggravating stress damage. This change can potentially introduce greater sensitivity to previously unaffected developmental stages such as floral meristem (panicle) initiation and spikelet differentiation, and further intensify vulnerability at the known sensitive gametogenesis and flowering stages. More than the mean temperature rise, increased variability and a more rapid increase in nighttime temperature compared with the daytime maximum present a greater challenge. This review addresses (1) the importance of vapour pressure deficit under fully flooded paddies and increased vulnerability of rice production to heat stress or intermittent occurrence of combined heat and drought stress under emerging water-saving rice technologies; (2) the major disconnect with high night temperature response between field and controlled environments in terms of spikelet sterility; (3) highlights the most important mechanisms that affect key grain quality parameters, such as chalk formation under heat stress; and finally (4), we model and estimate heat stress-induced spikelet sterility taking South Asia as a case study.

Knowing where, when, and how much rice is planted and harvested is crucial information for understanding the effects of policy, trade, and global and technological change on food security. We developed RiceAtlas, a spatial database on the seasonal distribution of the world's rice production. It consists of data on rice planting and harvesting dates by growing season and estimates of monthly production for all riceproducing countries. Sources used for planting and harvesting dates include global and regional databases, national publications, online reports, and expert knowledge. Monthly production data were estimated based on annual or seasonal production statistics, and planting and harvesting dates. RiceAtlas has 2,725 spatial units. Compared with available global crop calendars, RiceAtlas is nearly ten times more spatially detailed and has nearly seven times more spatial units, with at least two seasons of calendar data, making RiceAtlas the most comprehensive and detailed spatial database on rice calendar and production.

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We present in situ x-ray scattering measurements of the surface structures of PbTiO(3) (001) in equilibrium with PbO vapor. At 875 to 1025 K, a reconstruction having c(2x2) symmetry is present under most conditions, while a 1 x 6 reconstruction occurs under PbO-poor conditions. The atomic structure of the c(2x2) phase is found to consist of a single layer of an antiferrodistortive structure with oxygen cages counter-rotated by 10 degrees about the titanium ions.

SUMMARYProjections suggest that annual per capita water availability in the Indo-Ganga Basin (IGB) will reduce to a level typical for water-stressed areas. Producing more crop and livestock products, per unit of agricultural water invested, is advocated as a key strategy for future food production and environmental security in the basin. The objective of this study was to understand the spatio-temporal dynamics of water requirements for livestock feed production, attendant livestock water productivity (LWP) and implications for the future sustainable use of water resources. We focused on three districts in the IGB representing intensive (higher external inputs, e.g. fertilizer, water) and semi-intensive (limited external input) crop-livestock systems. LWP is estimated based on principles of water accounting and is defined as the ratio of livestock beneficial outputs and services to the water depleted and degraded in producing these. In calculating LWP and crop water productivity (CWP), livestock, land use, land productivity and climatic data were required. We used secondary data sources from the study districts, field observations and discussions with key informants to generate those data sets. Our result showed that the volume of water depleted for livestock feed production varied among the study systems and was highly affected by the type of feed and the attendant agronomic factors (e.g. cropping pattern, yield). LWP value was higher for intensive systems and affected by agricultural water partitioning approaches (harvest index, metaolizable energy). LWP tended to decrease between 1992 and 2003. This can be accounted for by the shift to a feeding regime that depletes more water despite its positive impacts on animal productivity. This is a challenging trend with the advent of and advocacy for producing more agricultural products using the same or lower volume of water input and evokes a need for balanced feeding, by considering the nutritive value, costs and water productivity of feed, and better livestock management to improve LWP.