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The effects of translucent polyethylene sheeting as a thermal covering to eradicate Pueraria montana (kudzu) were investigated at Clemson, South Carolina on a clay loam. In 2005, the highest reduction of live root crowns was observed where P. montana was covered for the entire growing season (May–October) with a reduction of 42% of live root crowns compared with the control plots. Where P. montana was covered for alternate weeks throughout the growing season live root crowns were reduced by 35%. Covering P. montana for one week and then uncovering for four weeks repeatedly through the season killed 24% of root crowns. In 2006, the second year of treatment to the same plots, the three solarization treatments had similar efficacy of about 97%. The use of polyethylene sheeting appears not to be cost‐effective for general control of large P. montana infestations, but may be useful for small patches.  相似文献   
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The green alga Caulerpa microphysa, which is native to Taiwan, has a relatively high economic value and a well-developed culture technique, and is used mainly as a foodstuff. Its extract has been shown to exhibit antitumor properties, but the polysaccharide content of the extract and its anti-inflammatory and wound-healing effects and moisture-absorption and -retention capacity remain unknown. Hence, the objective of this study was to evaluate the potential of the polysaccharides in C. microphysa extract (CME) for use in cosmetics. The overall polysaccharide yield from the CME was 73.93% w/w, with four molecular weight fractions. The polysaccharides comprised 59.36 mol% mannose, 27.16 mol% glucose, and 13.48 mol% galactose. In addition, the CME exhibited strong antiallergic, wound-healing, transdermal-delivery, and moisture-absorption and -retention effects. In conclusion, the results suggested that CME potentially has anti-inflammatory and wound-healing effects and a good moisture capacity, which can be used in cosmetic applications.  相似文献   
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In this study, two composite nanofibrous membranes of Polyvinylidenefluoride (PVDF) and [poly(vinylidenefluorideco-hexafluoropropylene)] (PVDF-co-HFP) prepared by the electrospinning process were employed in a direct contact membrane distillation (DCMD) system. We changed the pump flow rate and temperature difference to examine their effects on permeate flux and salt rejection. The SEM observations, porosity analyzer technique, and contact angle measurement indicated the nanobrous membrane with an average fiber diameter of 170 nm and maximum pore diameter distribution of 0.3 ??m is the best membrane for the DCMD system. However, the ability of the hydrophobic membrane affects the filtration efficiency of the DCMD system. The contact angle of the PVDF-HFP electrospun membrane (128°) shows better hydrophobic than the PVDF electrospun membrane (125 °). From the experiment of 12 hours, the salt rejection of PVDFHFP (99.9901 %) was better than that of PVDF composite membrane (99.9888 %) and was almost the same as that of the PTFE commercial membrane (99.9951 %). In addition, the permeate flux of the PVDF-HFP composite membrane is 4.28 kg/ m2hr higher than the PTFE commercial membrane.  相似文献   
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A marine polycyclic quinone-type metabolite, halenaquinone (HQ), was found to inhibit the proliferation of Molt 4, K562, MDA-MB-231 and DLD-1 cancer cell lines, with IC50 of 0.48, 0.18, 8.0 and 6.76 μg/mL, respectively. It exhibited the most potent activity against leukemia Molt 4 cells. Accumulating evidence showed that HQ may act as a potent protein kinase inhibitor in cancer therapy. To fully understand the mechanism of HQ, we further explored the precise molecular targets in leukemia Molt 4 cells. We found that the use of HQ increased apoptosis by 26.23%–70.27% and caused disruption of mitochondrial membrane potential (MMP) by 17.15%–53.25% in a dose-dependent manner, as demonstrated by Annexin-V/PI and JC-1 staining assays, respectively. Moreover, our findings indicated that the pretreatment of Molt 4 cells with N-acetyl-l-cysteine (NAC), a reactive oxygen species (ROS) scavenger, diminished MMP disruption and apoptosis induced by HQ, suggesting that ROS overproduction plays a crucial rule in the cytotoxic activity of HQ. The results of a cell-free system assay indicated that HQ could act as an HDAC and topoisomerase catalytic inhibitor through the inhibition of pan-HDAC and topoisomerase IIα expression, respectively. On the protein level, the expression of the anti-apoptotic proteins p-Akt, NFκB, HDAC and Bcl-2, as well as hexokinase II was inhibited by the use of HQ. On the other hand, the expression of the pro-apoptotic protein Bax, PARP cleavage, caspase activation and cytochrome c release were increased after HQ treatment. Taken together, our results suggested that the antileukemic effect of HQ is ROS-mediated mitochondrial apoptosis combined with the inhibitory effect on HDAC and topoisomerase activities.  相似文献   
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1.?The purpose of this study was to investigate the effects of different sources of dietary non-starch polysaccharides (NSP) on growth performance, development of gastrointestinal tract, and activities of pancreatic enzymes in goslings from 0 to 21 d of age.

2.?A total of 100 one-day-old White Roman female goslings were selected and randomly divided into 5 dietary treatment groups. Each group had 4 replicate cages (100 × 60 × 58 cm) of 5 goslings. Goslings in each group were given one of 5 isoenergetic and isonitrogenous semi-purified diets. Experimental diets were designed to contain 90 g/kg of different sources of dietary NSP from maize (control), barley hull, rice bran, wheat bran, or pectin, respectively, and 97·4 g/kg NSP were supplied by soybean meal.

3.?The goslings receiving the pectin diet had significantly higher viscosity in intestinal digesta than the other treatment diets. However, the daily feed intake, daily weight gain, and feed conversion ratio of goslings in the pectin group were significantly lower than those given the other diets.

4.?The relative weights of proventriculus, gizzard, liver and pancreas, as well as the relative weights and lengths of various intestinal segments in the goslings that received the pectin diet, were significantly higher than those receiving the other diets. The specific activities (SA) of amylase, lipase, trypsin, and chymotrypsin in the pancreatic tissue of goslings in the pectin group were significantly lower than those in the other groups.

5.?Goslings given a soluble NSP source (pectin) diet tended to exhibit inhibited growth and decreased activity of pancreatic enzymes. However, compared with maize, the inclusion of insoluble NSP sources from barley hull, rice bran, and wheat bran did not negatively affect growth and also were not significantly different among the treatment diets.  相似文献   

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To obtain a basal concentration of serum Haptoglobin (Hp) in cattle in Taiwan, Hp concentrations were measured from serum samples collected from 10 healthy heifers, every week for one year. The values were also compared with those collected from 15 cows diagnosed with postpartum metritis. The heifers were successfully impregnated by artificial insemination six months after the tests. Hp concentrations were also measured in the serum collected from 11 other cows within 3 weeks after parturition. The Hp assay developed in this study gave a good correlation (r=0.893)with Western blotting. The Hp concentration of 454 serum samples from the 10 heifers had a mean value of 83.6 +/- 34.1 mg/l, and there was no significant difference among individual heifers. The basal value of Hp in heifers was calculated as less than 73.6 mg/l. No significant difference in Hp concentration was observed among the 10 heifers during cold and warm seasons (19.8 +/- 2.2 degrees C vs 27.3 +/- 1.4 degrees C), or before and after pregnancy. The mean serum Hp concentration from cows suffering from postpartum reproductive disorders was 1133.5 +/- 627.1 mg/l, which was significantly greater than the serum of healthy heifers and postpartum cows (104.6 +/- 61.0 mg/l) (P<0.05). These results demonstrate that Hp concentration may be a useful indicator for cows with postpartum reproductive disorders.  相似文献   
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