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61.
Biotic and abiotic environmental factors affect plant nutritional quality and defensive compounds that confer plant resistance
to herbivory. Influence of leaf age, light availability, and girdling on foliar nutrition and defense of green ash (Fraxinus pennsylvanica Marsh) was examined in this study. Longevity of the emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), adults reared on green ash foliage subjected to these factors was assayed. Mature leaves
generally were more nutritious with greater amino acids and a greater ratio of protein to non-structural carbohydrate (P:C)
than young leaves, in particular when trees were grown in shade. On the other hand, mature leaves had lower amounts of trypsin
and chymotrypsin inhibitors, and total phenolics compared to young leaves. Lower defense of mature leaves alone, or along
with higher nutritional quality may lead to increased survival and longevity of emerald ash borer feeding on mature leaves.
Sunlight reduced amino acids and P:C ratio, irrespective of leaf age and girdling, and elevated total protein of young foliage,
but not protein of mature leaves. Sunlight also dramatically increased all investigated defensive compounds of young, but
not mature leaves. Girdling reduced green ash foliar nutrition, especially, of young leaves grown in shade and of mature leaves
grown in sun. However emerald ash borer performance did not differ when fed leaves from trees grown in sun or shade, or from
girdled or control trees. One explanation is that emerald ash borer reared on lower nutritional quality food may compensate
for nutrient deficiency by increasing its consumption rate. The strong interactions among leaf age, light intensity, and girdling
on nutrition and defense highlight the need for caution when interpreting data without considering possible interactions. 相似文献
62.
Mohammed Ibrahim Shukoor Filipe Natalio Muhammad Nawaz Tahir Matthias Wiens Marco Tarantola Helen Annal Therese Matthias Barz Stefan Weber Maxim Terekhov Heinz C. Schröder Werner E. G. Müller Andreas Janshoff Patrick Theato Rudolf Zentel Laura Maria Schreiber Wolfgang Tremel 《Advanced functional materials》2009,19(23):3717-3725
Here, design of the first pathogen‐mimicking metal oxide nanoparticles with the ability to enter cancer cells and to selectively target and activate the TLR9 pathway, and with optical and MR imaging capabilities, is reported. The immobilization of ssDNA (CpG ODN 2006) on MnO nanoparticles is performed via the phosphoramidite route using a multifunctional polymer. The multifunctional polymer used for the nanoparticle surface modification not only affords a protective organic biocompatible shell but also provides an efficient and convenient means for loading immunostimulatory oligonucleotides. Since fluorescent molecules are amenable to photodetection, a chromophore (Rhodamine) is introduced into the polymer chain to trace the nanoparticles in Caki‐1 (human kidney cancer) cells. The ssDNA coupled nanoparticles are used to target Toll‐like receptors 9 (TLR9) receptors inside the cells and to activate the classical TLR cascade. The presence of TLR9 is demonstrated independently in the Caki‐1 cell line by western blotting and immunostaining techniques. The magnetic properties of the MnO core make functionalized MnO nanoparticles potential diagnostic agents for magnetic resonance imaging (MRI) thereby enabling multimodal detection by a combination of MR and optical imaging methods. The trimodal nanoparticles allow the imaging of cellular trafficking by different means and simultaneously are an effective drug carrier system. 相似文献
63.
M. Balz H.A. Therese J. Li J.S. Gutmann M. Kappl L. Nasdala W. Hofmeister H.‐J. Butt W. Tremel 《Advanced functional materials》2005,15(4):683-688
The concepts of template‐induced crystallization on self‐assembled monolayers (SAMs) and the use of polymer additives are combined into a new strategy, where, through the cooperative interaction of a SAM matrix involved in the nucleation process, poly(acrylic acid), a dissolved polyelectrolyte, and the dissolved ions, hierarchically ordered mineral structures are formed. The adsorption of poly(acrylic acid) to the SAM is monitored using a quartz microbalance. Transmission electron microscopy measurements on samples that are taken from polyacrylate solution in short intervals after the start of the reaction reveals that nanometer‐sized particles pre‐formed in solution are being attached to the polymer template. These CaCO3 nanoparticles are still amorphous 20 min after the start of the mineralization process; the transformation from the amorphous to the crystalline phase takes place within the first 60 min of the reaction. The morphologies of the crystalline products exhibit characteristic differences from those that are obtained in crystallization experiments on self‐assembled monolayers without the polyelectrolyte. This model of cooperative formation of vaterite nanowires represents an alternative to current models of structure formation, where two‐phase systems (e.g., microemulsions or foams) act as a structure‐directing interface, or the mineralization process is caused by the diffusion of a hydrolyzable component from a non‐aqueous into an aqueous phase. 相似文献
64.
Two studies examined if decision makers show hindsight bias when feedback reflects upon their judgment. Study 1 investigated whether decision making heightens cognitive activity, and thereby reduces hindsight effects, or triggers self-serving mechanisms that prompt hindsight bias only when outcomes match favorably with decisions. Business students decided if they would purchase a company's stock, then received no feedback or feedback that the stock value increased or decreased. Consistent with a self-serving interpretation, relative to no-feedback participants, those whose outcomes matched favorably with their decisions showed hindsight bias and had a higher proportion of internal thoughts. In Study 2, favorable-feedback participants again showed hindsight bias, and had higher recall for decision-supportive items, but not when their tendency to take credit for success was suppressed. Discussion focuses on implications of decision makers' hindsight bias. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
65.
Therese Bormann Ralf Schumacher Bert Müller Matthias Mertmann Michael de Wild 《Journal of Materials Engineering and Performance》2012,21(12):2519-2524
Complex-shaped NiTi constructions become more and more essential for biomedical applications especially for dental or cranio-maxillofacial implants. The additive manufacturing method of selective laser melting allows realizing complex-shaped elements with predefined porosity and three-dimensional micro-architecture directly out of the design data. We demonstrate that the intentional modification of the applied energy during the SLM-process allows tailoring the transformation temperatures of NiTi entities within the entire construction. Differential scanning calorimetry, x-ray diffraction, and metallographic analysis were employed for the thermal and structural characterizations. In particular, the phase transformation temperatures, the related crystallographic phases, and the formed microstructures of SLM constructions were determined for a series of SLM-processing parameters. The SLM-NiTi exhibits pseudoelastic behavior. In this manner, the properties of NiTi implants can be tailored to build smart implants with pre-defined micro-architecture and advanced performance. 相似文献
66.
Therese Björnängen Johan Axnäs Yuri Eltsev Östen Rapp 《Journal of Low Temperature Physics》1999,117(5-6):1247-1251
The magnetoresistance of six untwinned YBa
2
Cu
3
O
7–
crystals has been measured above T
c
for
IBc. Fluctuation theories allowing for an in-plane coherence length anisotropy (
a
b
) were used in the analyses. The results suggest that the anisotropy, =
b
/
a
, is considerably lower than that expected from the resistivity ratio, i.e.,
. Some magnetoresistive measurements with the field in the ab-plane are also presented. 相似文献
67.
We studied foraging distribution, activity budgets, fish consumption, and energetics of double-crested cormorants (Phalacrocorax auritus) at two breeding colonies on Lake Champlain. Our objective was to determine if fish consumption and distribution of predation changed with movements of cormorants associated with efforts to reduce numbers of cormorants on one of the colonies. Wildlife managers reduced populations of cormorants on Young Island, Vermont by oiling their eggs, which resulted in dispersal of breeding cormorants 35 km south to Four Brothers Islands, New York. We found that as cormorants shifted from Young Island to the colony on Four Brothers Islands, energy demands, foraging distribution, and total fish consumption increased. Birds on Four Brothers Islands foraged a greater distance from the colony compared to birds on Young Island. Additionally, consumption of yellow perch (Perca flavescens) shifted to rainbow smelt (Osmerus mordax) when more birds bred on Four Brothers Islands. The dispersal of cormorants from Young Island to Four Brothers Islands reduced predation on yellow perch but increased overall fish consumption. Our estimates of fish consumption ranged from 322,000–425,000 kg of fish per year at Young Island to 899,000–1,086,000 kg of fish per year at Four Brothers Islands. Results from this study demonstrate secondary impacts of management on Young Island to unmanaged areas. 相似文献
68.
McLaren Timothy I. Smernik Ronald J. McLaughlin Michael J. McBeath Therese M. McCaskill Malcolm R. Robertson Fiona A. Simpson Richard J. 《Nutrient Cycling in Agroecosystems》2020,116(2):151-164
Nutrient Cycling in Agroecosystems - Grasslands are a globally important use of land for food and fibre production, which often require the addition of phosphorus (P) fertiliser to maximise plant... 相似文献
69.
Stitzer Maxine L.; Petry Nancy; Peirce Jessica; Kirby Kimberly; Killeen Therese; Roll John; Hamilton John; Stabile Patricia Q.; Sterling Robert; Brown Chanda; Kolodner Ken; Li Rui 《Canadian Metallurgical Quarterly》2007,75(5):805
Intake urinalysis test result (drug positive vs. negative) has been previously identified as a strong predictor of drug abuse treatment outcome, but there is little information about how this prognostic factor may interact with the type of treatment delivered. The authors used data from a multisite study of abstinence incentives for stimulant abusers enrolled in outpatient counseling treatment (N. M. Petry, J. M. Peirce, et al., 2005) to examine this question. The first study urine was used to stratify participants into stimulant negative (n = 306) versus positive (n = 108) subgroups. Abstinence incentives significantly improved retention in those testing negative but not in those testing positive. Findings suggest that stimulant abusers presenting to treatment with a stimulant-negative urine benefit from abstinence incentives, but alternative treatment approaches are needed for those who test stimulant positive at intake. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.
An orthogonal drawing of a graph is an embedding of the graph in the
rectangular grid, with vertices represented by axis-aligned boxes,
and edges represented by paths in the grid that only possibly
intersect at common endpoints. In this paper we study
three-dimensional orthogonal drawings and provide lower bounds for
three scenarios:
(1) drawings where the vertices have a bounded aspect ratio,
(2) drawings where the surfaces of vertices are proportional to their
degrees, and
(3) drawings without any such restrictions. Then we show that these
lower bounds are asymptotically optimal, by providing constructions
that in all scenarios match the lower bounds within a constant
factor. 相似文献