Effects of low temperature on photosynthetic characteristics in the super-high-yield hybrid rice 'Liangyoupeijiu' at the seedling stage.

To elucidate the resistance of high-yield hybrid rice (Oryza sativa L.) at the seedling stage to low temperature, photosynthetic characteristics, such as membrane lipid peroxidation, fatty acid composition, and chloroplast ultrastructure, were investigated in a newly developed super-hybrid rice ('Liangyoupeijiu') and a traditional chill-sensitive hybrid rice ('Shanyou63'), with 20°C as the control condition and 10°C as the low temperature treatment. Chlorophyll content, oxygen consumption by photosystem I, and oxygen production by photosystem II in the thylakoid membrane mainly decreased under the low-temperature treatment. The malondialdehyde content of 'Liangyoupeijiu' decreased slightly, while increases in membrane lipid peroxidation were greater in 10°C-treated than in 25°C-treated 'Shanyou63' seedlings. The index of unsaturated fatty acids increased in the two cultivars, particularly in 'Liangyoupeijiu'. No severe chloroplast ultrastructure damage was observed under cold stress, but the number of osmiophilic granules in 'Shanyou63' increased rapidly. The results indicate that compared to 'Shanyou63', 'Liangyoupeijiu' is more chill-resistant at the seedling stage.

Exchange bias in two-step artificially grown one-dimensional hybrid Co-BiFeO3 core-shell nanostructures.

One-dimensional core-shell nanostructures consisting of a ferromagnetic cobalt core and a multiferroic BiFeO3 (BFO) shell were fabricated by an artificial two-step methodology. The coupling between the ferromagnetic core and multiferroic shell manifests a significant exchange bias effect which gives a clear demonstration of the anti-ferromagnetic functionality of the BFO shell material. Exchange biases of 30 Oe and 60 Oe are observed at 300 K and at 5 K, respectively. Superparamagnetic contributions at lower temperatures play an important role in contributing to overall magnetic behavior. Dominant shape anisotropy causes parallel alignment of the easy magnetization axis along the axis of core-shell nanowires. A coherent mode of the magnetization reversal mechanism is observed by the angular dependence of coercivity (H c). This versatile two-step methodology can be employed to fabricate and investigate many other hybrid nanostructures leading to a vast scope of investigation for researchers.

Enhanced exchange bias and improved ferromagnetic properties in Permalloy-BiFe0.95Co0.05O3 core-shell nanostructures.

Hybrid core-shell nanostructures consisting of permalloy (Ni80Fe20) and multiferroic(BiFeO3, BFO/BiFe0.95Co0.05O3, BFC) materials were synthesized by a two-step method, based on wet chemical impregnation and subsequent electrodeposition within porous alumina membranes. Structural and magnetic characterizations have been done to investigate doping effect on magnetic properties and exchange bias. The magnetometry analysis revealed significant enhancements of the exchange bias and coercivity in NiFe-BFC core-shell nanostructures as compared with NiFe-BFO core-shell nanostructures. The enhancements can be attributed to the effective reduction of ferromagnet domain sizes between adjacent layers of core-shell structure. It indicates that it is possible to improve properties of multiferroic composites by site-engineering method. Our approach opens a pathway to obtain optimized nanostructured multiferroic composites exhibiting tunable magnetic properties.

Utilizing the anti-ferromagnetic functionality of a multiferroic shell to study exchange bias in hybrid core-shell nanostructures.

A three-step method has been employed to synthesize 1D core-shell nanostructures consisting of a ferromagnetic Co90Pt10 (CoPt) core and a La doped multiferroic Bi0.87La0.13FeO3 (BLFO) shell. La doping efficiently removes the secondary impurity phases in the multiferroic shell and exchange interaction gives a significant exchange bias effect demonstrating the anti-ferromagnetic functionality of Bi0.87La0.13FeO3.

Photosynthetic and biochemical activities in flag leaves of a newly developed superhigh-yield hybrid rice (Oryza sativa) and its parents during the reproductive stage.

Responses of net photosynthetic rates to intercellular CO(2) concentration (P (n)/C (i) curves) and photochemical characteristics were investigated in flag leaves of newly developed superhigh-yield hybrid rice (Oryza sativa L.) LiangYouPeiJiu (LYPJ) and its maternal PeiAi64S (PA64S) and paternal WuMang9311 (WM9311) lines grown in the field during the reproductive stage. The results showed that photosynthetic functions, such as the electron transport activities of photosystems and photophosphorylation, assessed in vivo from P (n)/C (i) curves under field conditions declined more or earlier than those obtained in vitro. The degradation of polypeptides of thylakoid membranes was slower than those for P (Ca=360) (light-saturated net photosynthetic rate measured at 360 mumol mol(-1)) and CE (carboxylation efficiency, obtained from the initial slope of the P (n)/C (i) curve). The initial inhibition of the PSII electron transport and oxygen-evolving activity induced by senescence occurred before the degradation of the oxygen-evolving complex. In comparison, LYPJ had intermediate photosynthetic functions in the early stage of leaf development, but greater photochemical activities in the mid and late stages. WM9311 showed a similar pattern of changes but lower values, and PA64S had higher values in the early stage but showed a faster rate of senescence than LYPJ. These findings implied that the hybrid LYPJ demonstrated intermediate photosynthetic activities between its parents in the early stage of leaf development, whereas it had higher photosynthetic activities than its parents in the mid and late stages, which may be responsible for its high yield.

[Morphological and histological studies of Chinese traditional drug "hua jiao" (pericarpium zanthoxyli) and its allied drugs].

The Chinese traditional drug "Hua Jiao" specified in the Chinese Pharmacopoeia 1990 edition is the dried pericarp of ripe fruit of Zanthoxylum schinifolium Sieb. et Zucc. or Z. bungeanum Maxim., family Rutaceae. It has been used for epigastric pain accompanied by cold sensation, vomiting, diarrhea and abdominal pain due to intestinal parasitosis, ascariasis and used externally for eczema. By the investigation of the drug resources in the main producing areas and distributing regions (Sichuan, Guangxi, Henan, Liaoning, Zhejiang, Anhui, Jiangsu and Shandong Provinces or Autonomous Regions), we found that there are pericarps derived from more than 18 spp. of Zanthoxylum used as drugs in China. In this paper, the morphological and histological characters of crude drugs derived from the following 8 species, viz. Zanthoxylum bungeanum Maxim., Z. schinifolium Sieb. et Zucc., Z. armatum DC., Z. simulans Hance, Z. avicennae (Lam.) DC., Z. ailanthoides Sieb. et Zucc., Z. molle Rehd. and Z. nitidum (Roxb.). DC. were described with illustrations. It was discovered that such features as the external characters of pericarp, the occurrence of hairs on fruit stalk, the presence and location of pigment and crystals of hesperidin, the thickness of the cell walls of endocarp and the presence and shape of nonglandular hairs on fruit stalk were important for the identification of these drugs.