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71.
Levee‐protected floodplains along the 125‐km LaGrange Segment (LGS) of the Illinois River were screened for their abiotic suitability for alternative ecosystem services (ESs), including wetland creation, habitat, floodwater denitrification and flood‐tolerant agriculture. The suitability framework developed for this study builds upon the Land Capability Potential Index and is informed by the current understanding of the linkages between river hydrology, hydraulics, floodplain soils, floodplain vegetation and floodplain nutrient cycling. In addition to screening these floodplain areas for alternative ESs, we demonstrate how this framework can be combined with economic assessments of current floodplain services to inform how strategic floodplain reconnection (i.e. restoration of hydrologic linkages between river and floodplain for the purpose of flood mitigation and provisioning of alternative ESs) could be used to work towards sustainable floodplain management. Results show that ESs increase with upstream distance from the LaGrange Lock and Dam. This is attributed to the operation of the lock and dam generating a water level that would result in the inundation of a substantial portion of floodplain (>70 km2) up to ?60 km upstream if the levees were to be removed or set back. Comparison of the profits from current floodplain agriculture with the potential profits of flood‐tolerant agriculture suggests that overcoming the economic costs of floodplain reconnection within the LGS will likely require both conversion of reconnected floodplain lands to flood‐tolerant agriculture and payments for ESs. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
72.
Antonio Zizzi Daniele Minardi Andrea Ciavattini Federica Giantomassi Rodolfo Montironi Giovanni Muzzonigro Roberto Di Primio Guendalina Lucarini 《Microscopy research and technique》2010,73(3):229-233
In the last years, physical and chemical methods of plasmid delivery have revolutionized the efficiency of nonviral gene transfer, and the success of gene therapy is largely dependent upon the development of gene‐delivery methods. The nonviral techniques that lead to a direct transfer of DNA into tissue fragments, like electroporation (EP) and lipofection delivery systems are still insufficiently investigated. Our aim was to test the efficiency of EP and lipofection protocols in endometrial and testicular tissue fragments, using a naked plasmid DNA encoding green fluorescent protein (GFP). Because the transfection efficiency depends upon several factors, we tried to optimize the transfection conditions by testing different lipofectamine 2000 and plasmid ratios, electrical parameters, and culture after transfection. Our results show that these two nonviral methods of gene delivery are feasible and efficient in gene transfection of endometrial and testicular tissue biopsies. We found that the most performing ratio of plasmid:lipofectamine was 10:50 for transient lipofection, whereas two pulses for 10 s at 960 μF of capacitance, 200 V of voltage were the most favorable electrical parameters for EP efficiency in the presence of 5 μL of phMGFP plasmid. After lipofection and EP, the highest GFP intensity was observed respectively after 48 and 72 h of tissue fragment culturing. In conclusion, nonviral methods are attractive for an improvement of the gene therapy and our protocol could provide useful indications for in vivo gene therapy applications. Microsc. Res. Tech., 2010. © 2009 Wiley‐Liss, Inc. 相似文献
73.
Spatially,Temporally, and Quantitatively Controlled Delivery of Broad Range of Molecules into Selected Cells through Plasmonic Nanotubes
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74.
Mohsen K. Keshavarz Dimitri Vasilevskiy Remo A. Masut Sylvain Turenne 《Journal of Electronic Materials》2014,43(6):2239-2246
Nanostructured bulk materials are regarded as a means of enhancing the performance of thermoelectric (TE) materials and devices. Powder metallurgy has the distinct advantage over conventional synthesis that it can start directly from nanosized particles. However, further processing, for example extrusion, usually requires elevated temperatures, which lead to grain growth. We have found that introduction of semiconductor nanoparticles of molybdenum disulfide (MoS2), a well-known solid lubricant, suppresses grain growth in bismuth telluride-based alloys, thus improving the extrusion process. Scanning electron microscope images show that adding MoS2 particles at concentrations of 0.2, 0.4, and 0.8 wt% to p-type (Bi0.2Sb0.8)2Te3, under otherwise identical extrusion conditions, reduces average grain size by a factor of four. Scherer’s formula applied to x-ray diffraction data indicates that average crystallite sizes (~17 nm) of powders are not significantly different from those of alloys extruded with MoS2 (~18 nm), which is in stark contrast with those for conventional alloy (Bi0.2Sb0.8)2Te3 extruded under the same conditions (~80 nm). Harman measurements of TE properties reveal a decrease of the thermal conductivity accompanied by reduction of the room-temperature figure of merit (ZT) from 0.9 to 0.7, because of a lower power factor. Above 370 K, however, the performance of alloys containing MoS2 surpasses that of (Bi0.2Sb0.8)2Te3, with reduction of the thermal conductivity which is more significant at temperatures above the cross point of the ZT values. 相似文献
75.
3D Nanostar Dimers with a Sub‐10‐nm Gap for Single‐/Few‐Molecule Surface‐Enhanced Raman Scattering
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76.
Although predominantly a disease of older adults, colorectal cancer affects the younger population with an incidence of two to six per cent. It is thought to carry a less favorable prognosis in the young than in the general population. This may be due to advanced stage of the tumor at diagnosis. This study is composed of 37 patients, aged 40 and younger, treated over a 20-year period for colorectal cancer at Louisiana State University Medical Center-Shreveport and E. A. Conway Hospital. It was performed to investigate the incidence, stage at diagnosis, and prognosis of colorectal cancer in these young patients. The location of the primary tumor was fairly evenly distributed throughout the colon and rectum in this population. Pain, weight loss, rectal bleeding, and nausea and vomiting were the most common presenting symptoms. A family history of colon cancer or premalignant lesions were not risk factors in this study. Seventy per cent of all patients were treated with curative intent, and 42 per cent of these patients developed recurrent disease. The patients in this review presented with a higher incidence of advanced disease. Thirty-seven per cent of the lesions were Duke's C and 22 per cent were Duke's D, with poor 5-year survival (11% and 0%, respectively) when compared with national studies. The absolute 5-year survival for all young patients with colorectal cancer was 26 per cent (5 of 19 patients). It is important for the surgeon to be aware of the potential for colorectal cancer in young patients and to take an aggressive approach to the diagnosis and early treatment of the disease. 相似文献
77.
78.
A mathematical correlation between collector area and auxiliary energy used in a solar hot water system was obtained by using TRNSYS program. Based on this correlation, optimum collector area was directly related to both economic factors and system parameters. A criteria for economic feasibility was obtained. A comparison of optimum area calculated by this analysis with optimum area based on f-chart data was in good agreement. 相似文献
79.
Bedini Remo Palagi Graziano Mancini Palao 《IEEE transactions on bio-medical engineering》1982,(3):209-213
The instrument described in a previous paper, "A new method for utilizing a standard electrocardiograph for in vivo clinical pacemaker analysis" [3] has been improved with the utilization of the charge-coupled device. 相似文献
80.
Remo P. Jutzeler van Wijlen 《European Journal of Lipid Science and Technology》2011,113(9):1077-1094
In our contemporary adipogenic environment even modest improvements in body fat mass could be of relevance. In the last years animal and human studies have investigated the potential benefit of CLA on body composition. However, inconclusive results are often derived from short‐term studies. Long‐term intervention trials with supplemental CLA on body composition have not been reviewed exclusively up to now. Therefore, the objective of this study was to review the evidence of prolonged CLA supplementation as well as its influence on body composition in humans, and to summarize results from safety assessments of CLA intake. A literature search was performed to find intervention trials with CLA supplementation and its effects on body composition, as well as on insulin sensitivity. Only prolonged (≥12 wk) studies on body composition were included. The investigated studies indicate a modest reduction and/or prevention of regain of body fat in overweight/obese subjects. Results on the influence of CLA on insulin sensitivity are inconsistent, with newer data rather adding to the safety of CLA. Impaired insulin sensitivity by CLA remains a safety concern, yet is seemingly restricted to diabetic subjects and single‐isomer application. A meta‐a2 lysis of extended studies only is warranted to quantitatively evaluate the effects of CLA on body composition. Future research may elucidate if CLA should be considered as a marginal missing, semi‐essential nutrient in our present diet. 相似文献