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81.
82.
Donato Spoltore Wibren D. Oosterbaan Samira Khelifi John N. Clifford Aurelien Viterisi Emilio Palomares Marc Burgelman Laurence Lutsen Dirk Vanderzande Jean Manca 《Liver Transplantation》2013,3(4):466-471
The non‐geminate recombination of charge carriers in polymer‐fullerene solar cells has been modeled in the last few years with a trap‐assisted recombination model, which states that the apparent recombination order depends on the concentration of trapped charges tailing into the band gap. Higher concentrations of trapped charges lead to higher apparent recombination orders. In this work, the mass fraction f of highly crystalline nanofibrillar P3HT to the total P3HT content in P3HT:PCBM solar cells is consistently varied, controlling the temperature of a nanofibers‐P3HT casting dispersion. A systematic study of the apparent recombination order, measured with a transient photovoltage technique, as a function of f is presented. A correlation is shown between the apparent recombination order, the P3HT crystallinity, and the trap concentration in the band gap measured with an admittance spectroscopy technique. 相似文献
83.
Lucy Wentworth Justin V. Meyers Sheeba Alam Andrew J. Russ M. Suresh Clifford S. Cho 《Cancer immunology, immunotherapy : CII》2013,62(1):149-159
We have previously observed that in vivo exposure to growing melanoma tumors fundamentally alters activated T cell homeostasis by suppressing the ability of naïve T cells to undergo antigen-driven proliferative expansion. We hypothesized that exposure of T cells in later stages of differentiation to melanoma would have similar suppressive consequences. C57BL/6 mice were inoculated with media or syngeneic B16F10 melanoma tumors 8 or 60 days after infection with lymphocytic choriomeningitis virus (LCMV), and splenic populations of LCMV-specific T cells were quantified using flow cytometry 18 days after tumor inoculation. Inoculation with melanoma on post-infection day 8 potentiated the contraction of previously activated T cells. This enhanced contraction was associated with increased apoptotic susceptibility among T cells from tumor-bearing mice. In contrast, inoculation with melanoma on post-infection day 60 did not affect the ability of previously established memory T cells to maintain themselves in stable numbers. In addition, the ability of previously established memory T cells to respond to LCMV challenge was unaffected by melanoma. Following adoptive transfer into melanoma-bearing mice, tumor-specific memory T cells were significantly more effective at controlling melanoma growth than equivalent numbers of tumor-specific effector T cells. These observations suggest that memory T cells are uniquely resistant to suppressive influences exerted by melanoma on activated T cell homeostasis; these findings may have implications for T cell–based cancer immunotherapy. 相似文献
84.
Silvia Pineiro Ashvini Chauhan Timkhite-kulu Berhane Rana Athar Guili Zheng Cynthia Wang Tamar Dickerson Xiaobing Liang Despoina S. Lymperopoulou Huan Chen Mary Christman Clifford Louime Wisal Babiker O. Colin Stine Henry N. Williams 《Microbial ecology》2013,65(3):652-660
The predatory Bacteriovorax are Gram-negative bacteria ubiquitous in saltwater systems that prey upon other Gram-negative bacteria in a similar manner to the related genus Bdellovibrio. Among the phylogenetically defined clusters of Bacteriovorax, cluster V has only been isolated from estuaries suggesting that it may be a distinct estuarine phylotype. To assess this hypothesis, the spatial and temporal distribution of cluster V and other Bacteriovorax phylogenetic assemblages along the salinity gradient of Chesapeake Bay were determined. Cluster V was expected to be found in significantly greater numbers in low to moderate salinity waters compared to high salinity areas. The analyses of water and sediment samples from sites in the bay revealed cluster V to be present at the lower salinity and not high salinity sites, consistent with it being an estuarine phylotype. Cluster IV had a similar distribution pattern and may also be specifically adapted to estuaries. While the distribution of clusters V and IV were similar for salinity, they were distinct on temperature gradients, being found in cooler and in warmer temperatures, respectively. The differentiation of phylotype populations along the salinity and temporal gradients in Chesapeake Bay revealed distinct niches inhabited by different phylotypes of Bacteriovorax and unique estuarine phylotypes. 相似文献
85.
B. Emma Huang David Clifford Colin Cavanagh 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2013,126(2):379-388
Selective phenotyping is a way of capturing the benefits of large population sizes without the need to carry out large-scale phenotyping and hence is a cost-effective means of capturing information about gene–trait relationships within a population. The diversity within the sample gives an indication of the efficiency of this information capture; less diversity implies greater redundancy of the genetic information. Here, we propose a method to maximize genetic diversity within the selected samples. Our method is applicable to general experimental designs and robust to common problems such as missing data and dominant markers. In particular, we discuss its application to multi-parent advanced generation intercross (MAGIC) populations, where, although thousands of lines may be genotyped as a large population resource, only hundreds may need to be phenotyped for individual studies. Through simulation, we compare our method to simple random sampling and the minimum moment aberration method. While the gain in power over simple random sampling for all tested methods is not large, our method results in a much more diverse sample of genotypes. This diversity can be applied to improve fine mapping resolution once a QTL region has been detected. Further, when applied to two wheat datasets from doubled haploid and MAGIC progeny, our method detects known QTL for small sample sizes where other methods fail. 相似文献
86.
Eduardo N. Taboada Clifford G. Clark Emma L. Sproston Catherine D. Carrillo 《Journal of microbiological methods》2013
Campylobacter remains one of the most common bacterial causes of gastroenteritis worldwide. Tracking sources of this organism is challenging due to the large numbers of human cases, and the prevalence of this organism throughout the environment due to growth in a wide range of animal species. Many molecular subtyping methods have been developed to characterize Campylobacter species, but only a few are commonly used in molecular epidemiology studies. This review examines the applicability of these methods, as well as the role that emerging whole genome sequencing technologies will play in tracking sources of Campylobacter spp. infection. 相似文献
87.
Dana R. Warren Kristin E. Judd Darren L. Bade Gene E. Likens Clifford E. Kraft 《Hydrobiologia》2013,717(1):119-131
Forested headwater streams play an important role in watershed nutrient dynamics, and wood is thought to be a key factor influencing habitat structure and nitrate-nitrogen dynamics in many forested streams. Because wood in streams can promote nitrogen uptake through denitrification, we hypothesized that nitrate uptake velocities would decrease following wood removal. We measured stream characteristics and nitrate uptake velocities before and after wood manipulation experiments conducted at Hubbard Brook Experimental Forest, NH, and the Sleepers River watershed, VT. The mean size of stream substrates and the amount of riffle habitat increased following wood removal. In contrast to our expectations, summer nitrate uptake velocities increased in the wood removal treatments relative to the reference treatments, possibly because wood removal increased the availability of stable substrates for periphyton growth, therefore increasing nitrate demand in these streams. Our results highlight that effects of wood on stream ecosystems occur through multiple pathways and suggest that the relative importance of these pathways may vary seasonally. 相似文献
88.
Julio C. López-Doval Antoni Ginebreda Thierry Caquet Clifford N. Dahm Mira Petrovic Damià Barceló Isabel Muñoz 《Hydrobiologia》2013,719(1):427-450
This review examines information generated over the past decade on the pollution of rivers in regions with a mediterranean-type climate (med-climate). Pollution has clearly increased in the last 100 years and is correlated with the development of industry, agriculture and human population. Important efforts have been made in some med-climate countries in order to characterise the chemical status of rivers. In addition, the number of chemical substances detectable in mediterranean-climate rivers (med-rivers), as well as the limits of detection, have improved from the development of better analytical methods. New substances detected in rivers are gaining attention. We discuss available knowledge regarding real and potential effects of pollutants on the biota and ecosystems in med-rivers, taking into account natural environmental characteristics of these rivers. The extreme seasonal conditions in med-rivers add to the potential risk because these characteristics can enhance pollutant effects. Efforts and policies to prevent or reduce pollution effects on med-rivers are linked to the knowledge about pollution pressures associated with the degree of economic development. Aquatic communities in med-rivers are more sensitive to pollutants because they are exposed to strong natural and human stressors. 相似文献
89.
90.
Devarsetty?PraveenEmail author Anushka?Patel Stephen?McMahon Dorairaj?Prabhakaran Gari?D.?Clifford Pallab?K.?Maulik Rohina?Joshi Stephen?Jan Stephane?Heritier David?Peiris 《Implementation science : IS》2013,8(1):137