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Feng Jiao

Publications and source records attributed to Feng Jiao.

7 recordsLinked to original sources
PubMed2006

Effects of carbonic anhydrase VIII deficiency on cerebellar gene expression profiles in the wdl mouse.

Recently, the waddles (wdl) mouse was identified as a carbonic anhydrase VIII (Car8) mutant. The mutation is associated with marked deficiency of Car8, an inositol triphosphate receptor 1-binding protein expressed at high levels in cerebellar Purkinje cells. To help unravel the molecular aberrations contributing to motor dysfunction in wdl mice, cerebellar gene expression profiles were examined in the mutants and their wild-type littermates. Genes involved in signaling, cell division, zinc ion-binding, synapse integrity and plasticity were downregulated in wdl mice. Several of the upregulated genes encode proteins that function in the Golgi apparatus which suggests that Car8 deficiency has important effects on synaptic vesicle formation and transport.

Animals↗
PubMed2006

Synthesis of ordered mesoporous Fe3O4 and gamma-Fe2O3 with crystalline walls using post-template reduction/oxidation.

Ordered mesoporous Fe(3)O(4) with crystalline walls (inverse spinel structure) has been synthesized for the first time, representing to the best of our knowledge, the first synthesis of a reduced mesoporous iron oxide. Synthesis was achieved by reducing ordered mesoporous alpha-Fe(2)O(3) (corundum structure) to Fe(3)O(4) spinel then to gamma-Fe(2)O(3) by oxidation, while preserving the ordered mesostructure and crystalline walls throughout. Such solid/solid transformations demonstrate the stability of the mesostructure to structural phase transitions from the hexagonal close packed oxide subarray of alpha-Fe(2)O(3) (corundum structure) to the cubic close packed subarray of Fe(3)O(4) spinel and gamma-Fe(2)O(3). Preliminary magnetic measurements reveal that the spins in both Fe(3)O(4) and gamma-Fe(2)O(3) are frozen at 295 K, despite the wall thickness (7 nm) being less than the lower limit for such freezing in corresponding nanoparticles (>8 nm).

Journal Article↗
PubMed2006

Ordered mesoporous Fe2O3 with crystalline walls.

Alpha-Fe(2)O(3) has been synthesized with an ordered mesoporous structure and crystalline walls that exhibit a near-single crystal-like order. The unique magnetic behavior of the material, distinct from bulk nanoparticles of alpha-Fe(2)O(3) or mesoporous Fe(2)O(3) with disordered walls, has been established. Magnetic susceptibility, Mössbauer, and neutron diffraction data show that the material possesses the same long-range magnetic order as bulk alpha-Fe(2)O(3), despite the wall thickness being less than the 8 nm limit below which magnetic ordering breaks down in nanoparticulate alpha-Fe(2)O(3), yet the Morin transition of bulk alpha-Fe(2)O(3) is absent. It is also shown by TEM, PXRD, and EXAFS that alpha-Fe(2)O(3) with the same ordered mesoporous structure but disordered walls contains small crystalline domains. Mössbauer and magnetic susceptibility data demonstrate that this material exhibits no long-range magnetic order but superparamagnetic behavior.

Journal Article↗
PubMed2005

A tree-decomposition approach to protein structure prediction.

This paper proposes a tree decomposition of protein structures, which can be used to efficiently solve two key subproblems of protein structure prediction: protein threading for backbone prediction and protein side-chain prediction. To develop a unified tree-decomposition based approach to these two subproblems, we model them as a geometric neighborhood graph labeling problem. Theoretically, we can have a low-degree polynomial time algorithm to decompose a geometric neighborhood graph G = (V, E) into components with size O(|V|((2/3))log|V|). The computational complexity of the tree-decomposition based graph labeling algorithms is O(|V|Delta(tw+1)) where Delta is the average number of possible labels for each vertex and tw( = O(|V|((2/3))log|V|)) the tree width of G. Empirically, tw is very small and the tree-decomposition method can solve these two problems very efficiently. This paper also compares the computational efficiency of the tree-decomposition approach with the linear programming approach to these two problems and identifies the condition under which the tree-decomposition approach is more efficient than the linear programming approach. Experimental result indicates that the tree-decomposition approach is more efficient most of the time.

Algorithms↗
PubMed2005

[Natural vegetation restoration and soil nutrient dynamics of abandoned farmlands in forest-steppe zone on Loess Plateau].

To understand the relationship between plant community succession and soil nutrient dynamics is crucial in intervening vegetation succession. This paper reported the results from a study carried out in a forest-steppe zone on the Loess Plateau, with emphasis on the vegetation characteristics and soil nutrient dynamics duringvegetation restoration on abandoned farmlands of this area. The results showed that under zonal habitat conditions, natural vegetation succession would turn toward the original vegetation communities, but the expected shrub or trees communities didn't occur after 40 approximately 50 years, and Stipa bungeana, Artemisia sacrorum, Bothriochloa ischaemun, Stipa grandis and Lespedeza davurica communities were still the widely distributed communities. Vegetation restoration had a significant effect on soil nutrient dynamics. In general, soil nutrient contents increased with restoration time, and extremely significant changes occurred in soil organic matter, total N, available N, and available K (P< 0.001),while only significant changes in available P (0.05 < P < 0.01) and no significant change in total P (P > 0.05). Moreover, the changes were also found in soil profile. Statistical analysis showed that from surface layer (0 approximately 20 cm) to deeper layer (to 60 cm), extremely significant changes occurred in soil organic matter, total N, available N, available K and available P (P < 0.001), and significant change in total P (P< 0.05). Soil nutrients intended to accumulate in surface layer. Further linear correlation analysis showed that soil organic matter, total N, available N and available K were significantly correlated each other ( P< 0.001), but didn't show correlation with soil total P and available P.

China↗