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51.
52.
Three ultrafiltration membranes in series with molar mass cutoffs of 130,000, 15,000, and 5,000 Da, respectively were used to pretreat Kraft pulp bleach plant effluent prior to biological treatment. The TOC (total organic carbon), COD (chemical oxygen demand) and AOX (adsorbable organic halogen) reductions for the permeate were 65, 70 and 85%, respectively with no significant change of toxicity. Treatment of the ultrafiltration permeate using tighter ultrafiltration (UF) and nanofiltration (NF) membranes with molar mass cutoffs less than 1,500 Da, yielded TOC and AOX reductions of 90 and 99%, respectively with a permeate Microtox EC50 level of 100%. 相似文献
53.
Wendy 《宠物世界(猫迷)》2018,(5)
正加拿大摄影师Holly SissonMonica Sisson这是一个让人质壁分离的家庭,两猫一狗,主人都是摄影师,住在加拿大的多伦多市。在她们的照片中,生活平淡可爱又满满当当,我们无法想象,如果这些画面里没有它们,会是什么样子。 相似文献
54.
HCI recognizes the importance of visions as both a design and futuring approach and a problem-solving technique. One challenge of visioning work is who can propose and shape IT visions and how they can achieve the widespread buy-in needed to make them efficacious. In this paper, we focus on the potential of making, open design, and open manufacturing for contributing toward, if not fully achieving, the broadening of participation in IT envisioning. We use Taiwan’s MakerPro, a manufacturers and IT R&D community as a case to unpack what collective IT visioning looks like, how it shapes IT agendas concretely, and the implications for open design/open manufacturing research agenda in HCI. Our findings reveal how MakerPro members constructed and developed visions for open design and open manufacturing in Taiwan, obstacles to such visions, and how these obstacles can be collaboratively overcome through a participative and even democratic process. We also show that the collective purposiveness not only defines a regional vision agenda but also embraces an entire nation’s future. 相似文献
55.
T. Schulze-König C. Maden E. Denk S.P.H.T. Freeman M. Stocker M. Suter H.-A. Synal T. Walczyk 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2010,268(7-8):752-755
A comparative study was made between the compact AMS system at the PSI/ETH Laboratory of Ion Beam Physics in Zurich with 0.5 MV terminal voltage and the 5 MV-AMS system at the Scottish Universities Environmental Research Centre (SUERC), Glasgow. Overall 34 urinary samples with 41Ca/40Ca ratios in the range from 4 × 10?11 to 3 × 10?10 were processed to CaF2 and aliquots of the same material were measured on both instruments.Measurements on the compact AMS system were performed in charge state 3+ achieving a transmission of 4% at 1.7 MeV beam energy. Under these conditions a suppression of the interference 41K is virtually impossible. However, samples with an excess of potassium can be identified by a shift of the 41Ca/41K peak in the ΔE ? E histogram of the gas ionization detector employed and a criterion for data rejection can be defined. An overall precision of ~4% and a 41Ca/40Ca background level of 5 × 10?12 have been reached.For studies with higher demands on the detection limit AMS systems like the one at SUERC are attractive: in charge state 5+ and using a gas stripper beam energy of 27 MeV, a transmission of 5%, a 41K suppression factor of ~500 and a 41Ca/40Ca background level of 3 × 10?14 are achieved.We demonstrate that both systems are well suited for large-scale 41Ca biomedical applications. 相似文献
56.
Wendy S. Smith David A. Johnston Harrison J. Wensley Suzanne E. Holmes Sopsamorn U. Flavell David J. Flavell 《International journal of molecular sciences》2020,21(22)
Cholesterol seems to play a central role in the augmentation of saporin-based immunotoxin (IT) cytotoxicity by triterpenoid saponins. Endolysosomal escape has been proposed as one mechanism for the saponin-mediated enhancement of targeted toxins. We investigated the effects of lipid depletion followed by repletion on Saponinum album (SA)-induced endolysosomal escape of Alexa Fluor labelled saporin and the saporin-based immunotoxin OKT10-SAP, directed against CD38, in Daudi lymphoma cells. Lipid deprived cells showed reduced SA-induced endolysosomal escape at two concentrations of SA, as determined by a flow cytometric method. The repletion of membrane cholesterol by low density lipoprotein (LDL) restored SA-induced endolysosomal escape at a concentration of 5 µg/mL SA but not at 1 µg/mL SA. When LDL was used to restore the cholesterol levels in lipid deprived cells, the SA augmentation of OKT10-SAP cytotoxicity was partially restored at 1 µg/mL SA and fully restored at 5 µg/mL SA. These results suggest that different mechanisms of action might be involved for the two different concentrations of SA and that endosomal escape may not be the main mechanism for the augmentation of saporin IT cytotoxicity by SA at the sub-lytic concentration of 1 µg/mL SA. 相似文献
57.
Maria Jos Rodríguez Francisca Herrera Wendy Donoso Ivn Castillo Roxana Orrego Daniel R. Gonzlez Jessica Zúiga-Hernndez 《International journal of molecular sciences》2020,21(22)
Liver fibrosis is a complex process associated to most types of chronic liver disease, which is characterized by a disturbance of hepatic tissue architecture and the excessive accumulation of extracellular matrix. Resolvin E1 (RvE1) is a representative member of the eicosapentaenoic omega-3 lipid derivatives, and is a drug candidate of the growing family of endogenous resolvins. Considering the aforementioned, the main objective of this study was to analyze the hepatoprotective effect of RvE1 in a rat model of liver fibrosis. Male Sprague-Dawley rats received diethylnitrosamine (DEN, 70 mg/mg body weight intraperitoneally (i.p)) as an inductor of liver fibrosis once weekly and RvE1(100 ng/body weight i.p) twice weekly for four weeks. RvE1 suppressed the alterations induced by DEN, normalizing the levels of alanine aminotransferase (ALT), albumin, and lactate dehydrogenase (LDH), and ameliorated DEN injury by decreasing the architecture distortion, inflammatory infiltration, necrotic areas, and microsteatosis. RvE1 also limited DEN-induced proliferation through a decrease in Ki67-positive cells and cyclin D1 protein expression, which is related to an increase of the levels of cleaved caspase-3. Interestingly, we found that RvE1 promotes higher nuclear translocation of nuclear factor κB (NF-κB)p65 than DEN. RvE1 also increased the levels of nuclear the nuclear factor erythroid 2–related factor 2 (Nrf2), but with no antioxidant effect, measured as an increase in glutathione disulfide (GSSG) and a decrease in the ratio of glutathione (GSH)/GSSG. Taken together, these results suggest that RvE1 modulates the fibrogenesis, steatosis, and cell proliferation in a model of DEN induced fibrosis. 相似文献
58.
SIR-C data quality and calibration results 总被引:5,自引:0,他引:5
Freeman A. Alves M. Chapman B. Cruz J. Kim Y. Shaffer S. Sun J. Turner E. Sarabandi K. 《Geoscience and Remote Sensing, IEEE Transactions on》1995,33(4):848-857
The SIR-C/X-SAR imaging radar took its first flight on the Space Shuttle Endeavour in April 1994 and flew for a second time in October 1994. This multifrequency radar has fully polarimetric capability at L- and C-band, and a single polarization at X-band (X-SAR). The Endeavour missions were designated the Space Radar Laboratory-1 (SRL-1) and -2 (SRL-2). Calibration of polarimetric L- and C-band data for all the different modes SIR-C offers is an especially complicated problem. The solution involves extensive analysis of pre-flight test data to come up with a model of the system, analysis of in-flight test data to determine the antenna pattern and gains of the system during operation, and analysis of data from over fourteen calibration sites distributed around the SIR-C/X-SAR orbit track. The SRL missions were the first time a multifrequency polarimetric imaging radar employing a phased array antenna has been flown in space. Calibration of SIR-C data products involved some unique technical problems given the complexity of the radar system. In this paper, the approach adopted for calibration of SIR-C data is described and the calibration performance of the data products is presented 相似文献
59.
Dechow CD Rogers GW Sander-Nielsen U Klei L Lawlor TJ Clay JS Freeman AE Abdel-Azim G Kuck A Schnell S 《Journal of dairy science》2004,87(10):3526-3533
The objectives of this study were to estimate genetic correlations among body condition scores (BCS) from various sources, dairy form, and measures of cow health. Body condition score and dairy form evaluated during routine type appraisal was obtained from the Holstein Association USA, Inc. A second set of BCS was obtained from Dairy Records Managements Systems (DRMS) and was recorded by producers that use PCDART dairy management software. Disease observations were obtained from recorded veterinarian treatments in several dairy herds in the United States. Estimated breeding values for diseases in Denmark were also obtained. Genetic correlations among BCS, dairy form, and cow health traits in the United States were generated with sire models. Models included fixed effects for age, DIM, and contemporary group. Random effects included sire, permanent environment, herd-year season for health traits, and error. Predicted transmitting abilities (PTA) for BCS and dairy form were correlated with estimated breeding values for disease in Denmark. The genetic correlation estimate between BCS from DRMS and BCS from the Holstein Association USA, Inc., was 0.85. The genetic correlation estimate between BCS and a composite of all diseases in the United States was -0.79, and PTA for BCS was favorably correlated with an index of resistance to disease other than mastitis in Denmark (0.27). Dairy form was positively correlated with a composite of all diseases in the United States (0.85) and was unfavorably correlated with an index for resistance to disease other than mastitis in Denmark (-0.29). Adjustment for protein yield PTA had a minimal affect on correlations between PTA for BCS or dairy form and disease in Denmark. Selection for higher body condition or lower dairy form with continued selection for yield may slow deterioration in cow health as a correlated response to selection for increased yield. 相似文献
60.
Butter composition and texture from cows with different milk fatty acid compositions fed fish oil or roasted soybeans 总被引:1,自引:0,他引:1
Bobe G Zimmerman S Hammond EG Freeman AE Porter PA Luhman CM Beitz DC 《Journal of dairy science》2007,90(6):2596-2603
Changing the milk fatty acid composition can improve the nutritional and physical properties of dairy products and their acceptability to consumers. A more healthful milk fatty acid composition can be achieved by altering the cow's diet, for example, by feeding supplemental fish oil (FO) or roasted soybeans (RSB), or by selecting cows with a more unsaturated milk fatty acid composition. We examined whether feeding supplemental FO or RSB to cows that had a more unsaturated milk fatty acid composition acted additively to produce butter with improved fatty acid composition and texture. Using a 3 × 3 Latin square design with 2 replications, we fed diets to multiparous Holstein cows (60 to 200 DIM) chosen for producing either more or less unsaturated milk fatty acid composition (n = 6 for each group) for three 3-wk periods. The control diet contained 3.7% crude fat and the 2 experimental diets contained, on a dry matter basis, 0.8% of additional lipids in the form of 0.9% of FO or 5% of RSB. The milk, collected in the third week of feeding, was used to make butter, which was analyzed for its fatty acid composition and physical properties. Dry matter intake, milk yield, and milk composition were not significantly affected by cow diet or by cow selection. Cows that produced a more unsaturated and healthful milk fat prior to the feeding study, according to a “health-promoting index” [HPI = (sum of % of unsaturated fatty acids)/ (%12:0 + 4 × %14:0 + %16:0)], maintained a higher HPI in their butter during the feeding study than did cows with a low HPI. Milk from cows fed supplemental FO or RSB yielded more unsaturated butters with a higher HPI. This butter also was softer when the cows were fed RSB. Feeding RSB to cows chosen for their high milk HPI yielded the most unsaturated butter with the highest HPI and softest texture. Thus, selecting cows with a more health-promoting milk fatty acid composition and feeding supplemental RSB can be used in combination to produce butter that has a consumer-friendly texture and a healthful fatty acid profile. 相似文献