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We aimed to compare the properties of seed banks in different types of Robinia pseudoacacia stands and different substratum layers. We established four Black locust plots (each 50 x 50 m) that included two second-generation stands and two third-generation stands. Spatial coordinates, diameter at breast height, and the heights of all trees were measured in the four plots. In each plot, we set a total of 259 points using the regular grid design method. At these points, we sampled the seed banks in the litter and soil (0-5 cm) layers. The coordinates of the 259 points were recorded. After the samples had been collected and screened, a germination trial was performed using the collected seeds from the different layers and stands. We used variogram and kriging interpolation geostatistical methods to analyze the distribution of the seed banks. A kernel density estimation map was generated to examine the relationship between the seed bank and trees in each stand. The results showed that seed bank density was high in the four stands (4005-7325 seeds.m-2), and was higher in the third-generation stands (6085 and 7325 seeds.m-2) than in the second-generation stands (4005 and 5659 seeds.m-2). The seed bank density in the litter layer (3225 seeds.m-2) exceeded that in the soil layer (2164 seeds.m-2). The spatial pattern of the seed banks varied among different stands and was positively correlated with the distribution of trees in each stand. Furthermore, we found that spatial autocorrelation in the seed banks occurred at a variety of scales. Seeds in the litter layer were significantly more active than those in the soil layer; the germination rate varied from 6.67% to 28.89%. The findings of this study suggest that the Robinia pseudoacacia plantation in the Luoning area may exhibit potential for regeneration from seeds, and this will be the focus of our future studies. [ABSTRACT FROM AUTHOR]

The crystallization kinetics of amorphous Sm[sub 8]Fe[sub 85]Si[sub 2]C[sub 5] alloy has been investigated. As the alloy is heated to 900 °C, the crystalline phases of the alloy are composed of α-Fe phase and Sm[sub 2](Fe, Si)[sub 17]C[sub x]. At the beginning of crystallization the activation energy of the α-Fe phase is about 425 kJ/mol, it remains relatively constant as the crystallized fraction of the α-Fe phase is below 70%, and then it declines with increasing the crystallized fraction. When the crystallized fraction of the Sm[sub 2](Fe, Si)[sub 17]C[sub x] is below 50%, the activation energy of crystallization of the phase remains between 518 and 530 kJ/mol, and then decreases with the crystallized fraction. The crystallization behavior of the α-Fe phase and Sm[sub 2](Fe, Si)[sub 17]C[sub x] essentially results in the formation of an α-Fe/Sm[sub 2](Fe, Si)[sub 17]C[sub x] composite microstructure with a coarse grain size in annealed Sm[sub 8]Fe[sub 85]Si[sub 2]C[sub 5] alloy, which is attributed to a difficult nucleation and an easy growth for both the α-Fe phase and Sm[sub 2](Fe, Si)[sub 17]C[sub x] in the alloy. Cu and Nb can be used to change the crystallization behavior of the α-Fe phase in the amorphous Sm[sub 8]Fe[sub 85]Si[sub 2]C[sub 5] alloy, which is helpful to the formation of the α-Fe/Sm[sub 2](Fe, Si)[sub 17]C[sub x] nanocomposite microstructure with a fine grain size for the α-Fe phase in the alloy. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The effect of DDAH/ ADMA/ NOS pathway in penile tissue of rats of different age was investigated to better understand the mechanism of age-related erectile dysfunction ( ED). The Sprague Dawley male rats were assigned as the young group (3 month old, n = 10) and the old group (18 month old, n = 10) respectively. Intracavernous pressure ( ICP) was measured before and after papaverine intracavernous injection. Pathology structure of penile tissue was evaluated under transmission electron microscope. The expression amounts of asymmetric dimethylarginine ( ADMA) and cyclic guanosine monophosphate ( cGMP) in penile tissue were detected by ELISA; the expression levels of isoform-specific DDAH and NOS were assessed via Western blot. Compared with the young group, the ICP in the old group rat decreased significantly (33.46 ± 5.37 versus 39.71 ± 3.67 mmHg, P = 0.02) after papaverine injection. Diffused fibrosis and impairment of endothelial cell were observed in corpus cavernosum in the old group rats. Higher level of ADMA (10.83 ± 0.96 versus 7.51 ± 1.39 μmol per gpro, P = 3.14 × 10−4) and lower level of cGMP (29.42 ± 3.84 versus 47.09 ± 6.07 nmol per gpro, P = 1.57 × 10−6) were detected in penile tissue of the old group compared with those of the young group. Expression of DDAH1, DDAH2, endothelial NOS ( eNOS) and neuronal NOS( nNOS) all decreased significantly in penile tissue of the old group rat. The DDAH/ ADMA/ NOS regulation pathway changes dramatically accompanying with lower ICP in old group rat compared with those of the young group. Such findings in rats are suggestive in understanding the mechanism of age-related ED in humans. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 1-year-old male Chinese infant who diagnosed with a cluster of small bony papules on the right wrist and with progressive osseous heteroplasia (POH). When the radiologic examination was performed, ossification in the dermis, subcutaneous tissue and muscles are found.

Inspired by the surface geometry and composition of the lotus leaf with its self-cleaning behavior, in this work, a TiO2@fabric composite was prepared via a facile strategy for preparing marigold flower-like hierarchical TiO2 particles through a one-pot hydrothermal reaction on a cotton fabric surface. In addition, a robust superhydrophobic TiO2@fabric was further constructed by fluoroalkylsilane modification as a versatile platform for UV shielding, self-cleaning and oil–water separation. The results showed TiO2 particles were uniformly distributed on the fibre surface with a high coating density. In comparison with hydrophobic cotton fabric, the TiO2@fabric exhibited a high superhydrophobic activity with a contact angle of ∼160° and a sliding angle lower than 10°. The robust superhydrophobic fabric had high stability against repeated abrasion without an apparent reduction in contact angle. The as-prepared composite TiO2@fabric demonstrated good anti-UV ability. Moreover, the composite fabric demonstrated highly efficient oil–water separation due to its extreme wettability contrast (superhydrophobicity/superoleophilicity). We expect that this facile process can be readily and widely adopted for the design of multifunctional fabrics for excellent anti-UV, effective self-cleaning, efficient oil–water separation, and microfluidic management applications. [ABSTRACT FROM AUTHOR]