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341.
In winter, juvenile salmonids hide within the substrate during the day and emerge to feed on drifting invertebrates at night. In channelized streams, where the streambed heterogeneity has been artificially reduced, suitable microhabitats (low‐flow refugia) may be in short supply. Therefore, restoration of stream habitat by enhancement structures might improve the overwintering conditions of juvenile salmonids. We used a set of artificial streams to test whether individually‐marked juvenile brown trout of two age‐classes (age‐0 and age‐1 trout) loose mass during the winter differently in channelized and semi‐natural streams. Fish of both age‐classes lost mass early in the winter (November to January), but age‐0 fish in the channelized streams lost more of their initial mass than did the restored‐stream fish (ca. 10% vs. 2.5% on average, respectively). They then exhibited zero‐growth in both treatments in late winter (January to April), and by early spring (May), the channelized‐stream fish had completely caught up for their greater initial mass loss. In control tanks where the fish were fed continuously, age‐0 trout exhibited zero‐growth from November to January, then gaining mass constantly through the rest of the experiment. Significant time*treatment interaction was also detected for age‐1 trout, but all differences were caused by the faster growth of fish in the control tanks, whereas the two channel treatments did not differ significantly. The shortage of suitable sheltering sites in the channelized streams apparently intensified competition and caused greater initial mass loss in age‐0 trout. Furthermore, growth compensation exhibited by juvenile trout may have negative impacts on the long‐term fitness of individuals. Therefore, by increasing the amount of sheltering sites, in‐stream restoration may have potential to enhance the overwintering success of juvenile salmonids. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
342.
Behnam Tajik Ari Voutilainen Jussi Kauhanen Moshen Mazidi Gregory Y. H. Lip Tomi-Pekka Tuomainen Masoud Isanejad 《Lipids》2022,57(2):141-149
The blood level of lipids, apolipoproteins, and lipid ratios are important predictors of some chronic diseases. However, their association with cardiometabolic multimorbidity (CMM) is less known. We evaluated a wide range of lipid profiles and lipid ratios, including low-density lipoprotein-cholesterol (LDL-C), very-low-density lipoprotein-cholesterol (VLDL-C), high-density lipoprotein-cholesterol (HDL-C), and apoA1 and B, as well triglyceride and total cholesterol with risk of incident CMM. In 1728 men aged 52.5 ± 5.2 years from the Kuopio Ischaemic Heart Disease were included in this study. We defined CMM as coexisting of two or more of stroke, type 2 diabetes mellitus (T2D), coronary heart disease (CHD). A Cox proportional hazard regression method was applied to evaluate the risk of CMM against the exposures. During the mean follow-up of 22.4 years, 335 men suffered from CMM conditions. Higher serum triglyceride and VLDL concentrations were associated with a higher risk of coexisting T2D-CHD (HRs 1.99 (95% CI, 1.12–3.53) and HRs 1.79 (95% CI, 1.04–3.11), respectively. Whereas higher HDL was associated with lower incident [HRs 0.49 (95% CI, 0.40–1.00)]. The HRs for coexisting T2D-CHD was 2.02 (95% CI, 1.01–3.07) for total cholesterol/HDL-C, 1.85 (95% CI, 1.04–3.29) for triglyceride/HDL-C, 1.69 (95% CI, 1.01–2.31) for Non-HDL-C/HDL-C, and 1.89 (95% CI, 1.03–2.46) for apoB/apoA1. In contrast, serum LDL-C/apoB ratios were inversely associated with the risk of coexisting T2D-CHD [HRs 0.50 (95% CI, 0.28–0.90)]. No associations were observed between our exposures and other CMM conditions. In conclusion, elevated triglyceride, VLDL-C, total cholesterol/HDL-C, TG/HDL-C, apoB/apoA1 as well as lower LDL-C/apoB were independently associated with the higher risk of T2D-CHD coexistence. 相似文献
343.
The effects of geocell reinforcement on the behavior of shell foundations were studied using PLAXIS 3D finite element software. For this purpose, conical and pyramidal geometries were adopted as shell foundations. The real honeycomb shape of geocell and rigid body behavior of shells were simulated in PLAXIS 3D. The numerical models for shell foundations and geocell reinforced foundations were separately validated using several laboratory studies in the literature. The validated models were extended to the shell foundations resting on geocell reinforced sandy beds. The inclusion of geocell-reinforcement provided more than 70% reduction in the settlement of pyramidal and conical shell foundations. The stress transferred to the sand beds were reduced and distributed a wider area compared to the unreinforced cases. The maximum improvement in the bearing capacity and the settlement were observed in the case of conical shell foundation. The effect of adopted geocell and shell configuration on the foundation behavior was also analyzed for realistic prototype foundation size. 相似文献
344.
Tiago Tavares Brito de Medeiros Aderbal M de Azevedo Silva André Leandro da Silva Leilson Rocha Bezerra Deuber L da Silva Agostini Diego Lomonaco Vasconcelos de Oliveira Selma E Mazzetto Lloyd R Viana Kotzebue Jéssica Ribeiro Oliveira Gabriella S Barbosa Souto Ariádne de Barros Carvalho Antonio J Netto Ronaldo Lopes Oliveira 《Journal of the science of food and agriculture》2019,99(3):1078-1087
345.
Musa Makiyyu Abdullahi Xu Da Sun Feng Shao Hong Dong Xiangting Azis Raba’ah Syahidah Ugya Adamu Yunusa Ari Hadiza Abdullahi 《Journal of Materials Science: Materials in Electronics》2022,33(5):2375-2385
Journal of Materials Science: Materials in Electronics - Pure zinc ferrite, ZnFe2O4 and aluminum-doped zinc ferrite, Al: ZnFe2O4 (0.5% Al) nanofibers were prepared by the combination of... 相似文献
346.
Influence of extraction method and storage conditions on the volatile oil of wormwood (Artemisia absinthium L.) 总被引:1,自引:0,他引:1
Amaia Ariño Inés Arberas Gustavo Renobales J. B. Domínguez 《European Food Research and Technology》1999,209(2):126-129
In order to determine the best extraction procedure for volatile oil composition studies in wormwood (Artemisia absinthium L.), several extraction techniques have been investigated. In pentane extracts obtained using microwave or ultrasound sources
of radiation, no thermic degradations occurred, but high amounts of heavy oils and waxes resulted, causing trouble in the
gas chromatographic analysis. Headspace extraction provided the most volatile constituents, but high molecular weight compounds
were not extracted. Simultaneous distillation-extraction resulted in the most adequate extraction procedure for volatile oil
composition studies since the required compounds were extracted with minimum degradations when the distillation time was no
longer than 30 min. Freezing and drying processes did not greatly affect the percentage composition of wormwood volatile oil.
Received: 29 June 1998 / Revised version: 8 October 1998 相似文献
347.
Efficient decomposition of environmentally persistent perfluorocarboxylic acids by use of persulfate as a photochemical oxidant 总被引:6,自引:0,他引:6
Hori H Yamamoto A Hayakawa E Taniyasu S Yamashita N Kutsuna S Kiatagawa H Arakawa R 《Environmental science & technology》2005,39(7):2383-2388
Photochemical decomposition of persistent perfluorocarboxylic acids (PFCAs) in water by use of persulfate ion (S2O8(2-)) was examined to develop a technique to neutralize stationary sources of PFCAs. Photolysis of S2O8(2-) produced highly oxidative sulfate radical anions (SO4-), which efficiently decomposed perfluorooctanoic acid (PFOA) and other PFCAs bearing C4-C8 perfluoroalkyl groups. The major products were F- and CO2; also, small amounts of PFCAs with shorter than initial chain lengths were detected in the reaction solution. PFOA at a concentration of 1.35 mM (typical of that in untreated wastewater after an emulsifying process in fluoropolymer manufacture) was completely decomposed by a photochemical system with 50 mM S2O8(2-) and 4 h of irradiation from a 200-W xenon-mercury lamp. The initial PFOA decomposition rate was 11 times higherthan with photolysis alone. All sulfur-containing species in the reaction solution were eventually transformed to sulfate ions by this method. This method was successfully applied to the decomposition of perfluorononanoic acid contained in a floor wax solution. 相似文献
348.
Cancer stem cells (CSC) have been identified in several types of solid tumors. In some cases, CSC may be the source of all the tumor cells, the cause of the tumor’s resistance to chemotherapeutic agents, and the source of metastatic cells. Thus, a combination therapy targeting non-CSC tumor cells as well as specifically targeting CSCs holds the potential to be highly effective. Natural products (NPs) have been a historically rich source of biologically active compounds and are known for their ability to influence multiple signaling pathways simultaneously with negligible side effects. In this review, we discuss the potential of NPs in targeting multiple signaling pathways in CSC and their potential to augment the efficacy of standard cancer therapy. Specifically, we focus on the anti-CSC activities of flavonoids, FDA-approved drugs originating from natural sources. Additionally, we emphasize the potential of NPs in targeting microRNA-mediated signaling, given the roles of microRNA in the maintenance of the CSC phenotype. 相似文献
349.
The effect of gamma radiation on moisture content, total mold counts, Aspergillus counts, and aflatoxins of three hot pepper hybrids (Sky Red, Maha, and Wonder King) was investigated. Whole dried peppers packed in polyethylene bags were gamma irradiated at 0 (control), 2, 4, and 6 kGy and stored at 25°C for 90 days. Gamma radiation proved to be effective in reducing total mold and Aspergillus counts in a dose-dependent relationship. Total mold counts in irradiated peppers immediately after treatments were significantly lowered compared with those in nonirradiated samples, achieving 90 and 99% reduction at 2- and 4-kGy doses, respectively. Aspergillus counts were significantly reduced, by 93 and 97%, immediately after irradiation at doses of 2 and 4 kGy, respectively. A radiation dose of 6 kGy completely eliminated the population of total molds and Aspergillus fungi. The evolution of total molds in control and irradiated samples indicated no further fungal proliferation during 3 months of storage at 25°C. Aflatoxin levels were slightly affected by radiation doses of 2 and 4 kGy and showed a nonsignificant reduction of 6% at the highest radiation dose of 6 kGy. The distinct effectiveness of gamma radiation in molds and aflatoxins can be explained by the target theory of food irradiation, which states that the likelihood of a microorganism or a molecule being inactivated by gamma rays increases as its size increases. 相似文献
350.
Sarah E. Blitz Ari D. Kappel Florian A. Gessler Neil V. Klinger Omar Arnaout Yi Lu Pier Paolo Peruzzi Timothy R. Smith Ennio A. Chiocca Gregory K. Friedman Joshua D. Bernstock 《International journal of molecular sciences》2022,23(3)
Oncolytic virotherapy is a rapidly progressing field that uses oncolytic viruses (OVs) to selectively infect malignant cells and cause an antitumor response through direct oncolysis and stimulation of the immune system. Despite demonstrated pre-clinical efficacy of OVs in many cancer types and some favorable clinical results in glioblastoma (GBM) trials, durable increases in overall survival have remained elusive. Recent evidence has emerged that tumor-associated macrophage/microglia (TAM) involvement is likely an important factor contributing to OV treatment failure. It is prudent to note that the relationship between TAMs and OV therapy failures is complex. Canonically activated TAMs (i.e., M1) drive an antitumor response while also inhibiting OV replication and spread. Meanwhile, M2 activated TAMs facilitate an immunosuppressive microenvironment thereby indirectly promoting tumor growth. In this focused review, we discuss the complicated interplay between TAMs and OV therapies in GBM. We review past studies that aimed to maximize effectiveness through immune system modulation—both immunostimulatory and immunosuppressant—and suggest future directions to maximize OV efficacy. 相似文献