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1.
This research deals with the investigating the effect of nanoparticles on the various properties of nanocomposite fabrics produced from melt spinning of various blend ratios of prepared masterbatch containing Ag/TiO2 nanoparticles. The results revealed that the wear properties of modified fabrics improved as compared to pure fabrics with a trend justified considering modulus or crystallinity of fabrics with opposite effects. About 40 % UV protection enhancement has been obtained applying this kind of nanoparticles in the close relationship with the crimp contraction of textured yarns. A considerable improvement in the garment comfort has been recorded for nanocomposite sample containing 1 wt% nanoparticles. The lower permeability at low environment temperature and a higher at higher one, as compared to the pure sample, were obtained using this sample. It is highly interesting that these desirable changes in permeability can be achieved in the range of common environment temperatures (15–35 °C) being adapted to the human body requirements. The changing point is about 25 °C exactly meeting the body requirements by changing environment temperatures. A UV-induced solid state nanocomposite interaction increasing wear properties of UV-irradiated nanocomposite fabrics has been discovered.  相似文献   
2.

Background:

Skin flap grafting is a popular approach for reconstruction of critical skin and underlying soft tissue injuries. In a previous study, we demonstrated the beneficial effects of two 5α-reductase inhibitors, azelaic acid and finasteride, on tissue survival in a rat model of skin flap grafting. In the current study, we investigated the involvement of nitric oxide and inducible nitric oxide synthase (iNOS) in graft survival mediated by these agents.

Methods:

A number of 42 male rats were randomly allocated into six groups: 1, normal saline topical application; 2, azelaic acid (100 mg/flap); 3, finasteride (1 mg/flap); 4, injection of L-NG-nitroarginine methyl ester (L-NAME) (i.p., 20 mg/kg); 5, L-NAME (20 mg/kg, i.p.) + azelaic acid (100 mg/flap, topical); 6, L-NAME (20 mg/kg, i.p.) + finasteride (1 mg/flap, topical). Tissue survival, level of nitric oxide, and iNOS expression in groups were measured.

Results:

Our data revealed that azelaic acid and finasteride significantly increased the expression of iNOS protein and nitric oxide (NO) levels in graft tissue (P < 0.05). These increases in iNOS expression and NO level were associated with higher survival of the graft tissue.

Conclusion:

It appears that alterations of the NO metabolism are implicated in the azelaic acid- and finasteride-mediated survival of the skin flaps.Key Words: Finasteride, Azelaic acid, Surgical flaps, Nitric oxide, Nitric oxide synthase Type II  相似文献   
3.

Purpose

The main objective of this study was to examine the potential of using hyperspectral image analysis for prediction of total carbon (TC), total nitrogen (TN) and their isotope composition (δ13C and δ15N) in forest leaf litterfall samples.

Materials and methods

Hyperspectral images were captured from ground litterfall samples of a natural forest in the spectral range of 400–1700 nm. A partial least-square regression model (PLSR) was used to correlate the relative reflectance spectra with TC, TN, δ13C and δ15N in the litterfall samples. The most important wavelengths were selected using β coefficient, and the final models were developed using the most important wavelengths. The models were, then, tested using an external validation set.

Results and discussion

The results showed that the data of TC and δ13C could not be fitted to the PLSR model, possibly due to small variations observed in the TC and δ13C data. The model, however, was fitted well to TN and δ15N. The cross-validation R2 cv of the models for TN and δ15N were 0.74 and 0.67 with the RMSEcv of 0.53% and 1.07‰, respectively. The external validation R2 ex of the prediction was 0.64 and 0.67, and the RMSEex was 0.53% and 1.19 ‰, for TN and δ15N, respectively. The ratio of performance to deviation (RPD) of the predictions was 1.48 and 1.53, respectively, for TN and δ15N, showing that the models were reliable for the prediction of TN and δ15N in new forest leaf litterfall samples.

Conclusions

The PLSR model was not successful in predicting TC and δ13C in forest leaf litterfall samples using hyperspectral data. The predictions of TN and δ15N values in the external litterfall samples were reliable, and PLSR can be used for future prediction.
  相似文献   
4.
Saturated hydraulic conductivity (Ksat) is regarded as a key soil physical variable to determine soil infiltration rate, percolation depth and other hydrological processes. The purpose of this study was to determine the best soil sampling’s ring size for measuring Ksat. For this purpose, 25 rings with five different diameters (2, 3, 4, 5 and 6 inch) and with the same depth of 20 cm (five replicates) were hammered in close vicinity to each other into the ground of undisturbed loess deposits of a small farm to measure Ksat and bulk density. Hydraulic conductivity was measured at three constant loads of 22, 27 and 32 cm. The results showed that the ring with the internal diameter of 6 inches had the minimum variation coefficient and maximum Ksat for all the three hydraulic heads. In addition, the bulk density of this ring size was less than the other rings.  相似文献   
5.
6.
The one dimensional (1D) Ni-ZnO nanoparticles have been synthesized by a simple hydrothermal method. A novel photocatalyst of nanostructured Ni-ZnO which immobilized on polyacrylonitrile nanofibers were successfully fabricated using electrospinnig technique. The structures of nanofibers were characterized by various techniques including Scanning Electron Microscope (SEM), X-ray powder Diffraction (XRD), Fourier transform infrared (FT-IR), UV-Vis diffuse reflectance (DR) and thermogravimetric analys (TGA). The Ni-ZnO/PAN nanofibers photodegradation efficiency was optimized with factorial design method in order to act highly effective in the photocatalytic degradation of Methyle orange (MO). The highest decolorizing efficiencies using introduced material were achieved by 0.8 g l -1 of catalyst and 10 mg l -1 of MO at natural pH under visible light irradiation. The obtained results exhibited that Ni-ZnO/PAN nanofibers have high visible light photocatalitic activities. Overall, the presented material can be used as an efficient, low cost and healthily secure photocatalyst in the field of water treatment.  相似文献   
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9.
This study assessed the feasibility of identifying asymptomatic viral shedders using a novel TaqMan real-time PCR on trunk washes and swabs from the conjunctiva, palate and vulva of elephants. Six elephants from a UK collection were sampled weekly over a period of 11 weeks for this study. The herd prevalence of elephant endotheliotropic herpesvirus-1 (EEHV-1) was 100 per cent by PCR. The virus DNA was detected in all the sampling sites; however, the prevalence of virus DNA in the conjunctiva swabs was higher. In addition, Asian elephants from two continental European collections were sampled once and one animal tested positive on a trunk wash. The virus from this animal was phylogenetically typed as EEHV-1A based on 231 nucleotides of the terminase gene.  相似文献   
10.

Objective

To examine the maturational competence, embryo development and expression of genes involved in oocyte maturation and cumulus expansion (GDF9, BMP15, HAS2, TNFAIP6, FGF17 and FSHr) following two standard methods of bovine COCs vitrification.

Methods

Bovine cumulus-oocyte complexes (COCs) were aspirated from slaughtered ovaries and then distributed into three groups: non-vitrified COCs (control), vitrification 1 group (V1); vitrification was performed by 15% ethylene glycol (EG) and 15% DMSO in holding media (TCM-199 with 20% FCS); and vitrification 2 group (V2); vitrification was performed by 40% EG in holding media. After vitrification, COCs were warmed in two steps and cultured and then evaluated for nuclear maturation, embryo development and gene expressions.

Results

The mean (±SD) percentages of nuclear maturation and blastocyst/cleaved were higher in control group (79.5 ± 8.0 and 31.0 ± 5.1%) than the V1 (34.8 ± 9.1 and 4.4 ± 5.1%) and V2 (47.8 ± 11.7 and 7.1 ± 5.8%) groups (P < 0.05), respectively. Further, COCs in V2 group showed higher mean (±SD) percentages of cleavage compared to V1 group (31.8 ± 1.0 vs 21.7 ± 2.8%; P < 0.05). GDF9 and BMP15 expression levels were higher in COCs in the control than of the vitrification groups (P < 0.05). In addition, expression level of GDF9 and BMP15 was higher in V2 group than in V1group (P < 0.05). The expression of HAS2 and FGF17 in V1 group was lower (P < 0.05) than that of the V2 groups.

Conclusions

Expression of oocyte maturation genes was affected by vitrification procedure and conditions. Using EG alone for vitrification of bovine immature COCs, resulted in higher expression of GDF9, BMP15 and production of more in vitro matured and cleaved oocytes.
  相似文献   
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