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61.
1. Although preference–performance relationships in insects are typically studied in a bi-trophic context, it is well known that host plants can affect both the preference and performance of natural enemies of herbivorous insects. 2. This study presents evidence from field and laboratory studies that two species of milkweeds, the putatively less defended Asclepias incarnata and the putatively more defended Asclepias syriaca, differentially affect adult oviposition and larval performance in Aphidoletes aphidimyza, an aphid-feeding predatory midge, independent of aphid density. 3. Host plant species affected predatory fly larvae abundance by a factor of 50 in the field and a factor of 8 in the laboratory. Larval and adult emergence rates in our laboratory studies provided strong evidence for reduced performance on A. syriaca. Oviposition in choice and no-choice settings provided some evidence for preference for A. incarnata, and a potentially suppressive effect of A. syriaca. 4. The results provide limited support for the hypothesis that natural selection can lead to positive correlations between adult oviposition preferences and larval performance upon various food sources, even when predatory insects oviposit onto host plants of their herbivorous prey. 5. Preference and performance are not perfectly aligned in this system, however, because ovipositing females do not reject A. syriaca entirely. Potential explanations for mismatches between preference and performance in this system include the neural constraints associated with being a generalist, adaptive time-limited foraging strategies, and unique evolutionary histories of laboratory colonies compared with wild insects. 相似文献
62.
63.
Andreas König 《European Journal of Wildlife Research》2008,54(1):101-109
Throughout Central Europe, foxes have taken over urban areas as their habitat. In Southern Germany, these foxes are also carriers
of the small fox tapeworm, which causes a serious zoonotic infection in humans. Therefore, a survey was carried out in a suburb
of the city of Munich. A postal questionnaire was used to analyse the attitudes, opinions and fears of these participants
towards their urban foxes and the background to these attitudes. Questionnaires were sent to all households with gardens and
collected in again via the community council. Seven hundred and seventy-nine or 31% of questionnaires were returned. Only
a few people are afraid of the fox itself; however, 55% are afraid of the fox tapeworm. Worming the animals is the preferred
counter-measure, with 81% in favour. The majority of inhabitants are pleased to see a fox in the community and feel the animals
have a right to live. People are afraid of the tapeworm either because they have children in the household or because of increased
knowledge of the subject or because it has increasingly become an issue. On the basis of the results of this study, it is
to be expected that radical solutions such as killing the foxes are unlikely to be accepted among the population. Worming
of the foxes does, however, meet with general approval. 相似文献
64.
Anne F Mannion Stephane Kämpfen Urs Munzinger Ines Kramers-de Quervain 《Arthritis research & therapy》2009,11(5):R139-13
Introduction
Patient's expectations are variably reported to influence self-rated outcome and satisfaction after medical treatment; this prospective study examined which of the following was the most important unique determinant of global outcome/satisfaction after total knee arthroplasty (TKA): baseline expectations; fulfilment of expectations; or current symptoms and function. 相似文献65.
Robert M Bennett Ronald Friend Kim D Jones Rachel Ward Bobby K Han Rebecca L Ross 《Arthritis research & therapy》2009,11(4):R120-14
Introduction
The Fibromyalgia Impact Questionnaire (FIQ) is a commonly used instrument in the evaluation of fibromyalgia (FM) patients. Over the last 18 years, since the publication of the original FIQ, several deficiencies have become apparent and the cumbersome scoring algorithm has been a barrier to widespread clinical use. The aim of this paper is to describe and validate a revised version of the FIQ: the FIQR. 相似文献66.
SUMMARY The current concept of the order Asaphida was proposed to accommodate some Cambrian and Ordovician trilobite clades that are characterized by the possession of a ventral median suture. The family Tsinaniidae was recently suggested to be a member of the order Asaphida on the basis of its close morphological similarity to Asaphidae. Postembryonic development of the tsinaniid trilobite, Tsinania canens , from the Furongian (late Cambrian) Hwajeol Formation of Korea, reveals that this trilobite had an adult-like protaspis. Notable morphological changes with growth comprise the effacement of dorsal furrows, sudden degeneration of pygidial spines, regression of genal spines, and loss of a triangular rostral plate to form a ventral median suture. Programmed cell death may be responsible for degenerating the pygidial and genal spines during ontogeny. Morphological changes with growth, such as the loss of pygidial spines, modification of pleural tips, and effacement of dorsal furrows, suggest that T. canens changed its life mode during ontogeny from benthic crawling to infaunal. The protaspid morphology and the immature morphology of T. canens retaining genal and pygidial spines suggest that tsinaniids bear a close affinity to leiostegioids of the order Corynexochida. Accordingly, development of a ventral median suture in T. canens demonstrates that the ventral median suture could have evolved polyphyletically, and thus the current concept of the order Asaphida needs to be revised. 相似文献
67.
F. L. Laksmana P. J. A. Hartman Kok H. Vromans H. W. Frijlink K. Van der Voort Maarschalk 《AAPS PharmSciTech》2009,10(3):732-742
Next to the coating formulation, process conditions play important roles in determining coating quality. This study aims to
develop an operational window that separates layering from agglomeration regimes and, furthermore, the one that leads to the
best coating quality in a fluidized bed coater. The bed relative humidity and the droplet size of the coating aerosol were
predicted using a set of engineering models. The coating quality was characterized using a quantitative image analysis method,
which measures the coating thickness distribution, the total porosity, and the pore size in the coating. The layering regime
can be achieved by performing the coating process at a certain excess of the viscous Stokes number (ΔSt
v). This excess is dependent on the given bed relative humidity and droplet size. The higher the bed relative humidity, the
higher is the ΔSt
v required to keep the process in the layering regime. Further, it is shown that using bed relative humidity and droplet size
alone is not enough to obtain constant coating quality. The changes in bed relative humidity and droplet size have been identified
to correlate to the fractional area of particles sprayed per unit of time. This parameter can effectively serve as an additional
parameter to be considered for a better control on the coating quality. High coating quality is shown to be achieved by performing
the process close to saturation and spraying droplets small enough to obtain high spraying rate, but not too small to cause
incomplete coverage of the core particles. 相似文献
68.
The relationship between neutral and adaptive genetic diversity is important to understand in assessing the implications of a population bottleneck. Fitness-related genes, such as those of the major histocompatibility complex (MHC), may be influenced by selection, and so retain diversity even when it is lost at neutral markers. We measured MHC class I variation in an archaic reptile species Sphenodon guntheri [North Brother Island (NBI) tuatara], which naturally occurs on one 4 ha island in Cook Strait, New Zealand, and has low levels of microsatellite diversity. MHC variation in S. guntheri was compared with microsatellite DNA variation, and with MHC variation in a large population of Sphenodon punctatus (Cook Strait tuatara) on Stephens Island. The NBI population shows significantly decreased levels of genetic diversity compared with the Stephens Island population. Only three different MHC sequences and three genotypes were found on NBI, compared with 15 sequences and 21 genotypes in a similar sample size from Stephens Island. Two sequences appear to be unique to the NBI population. The assortment of sequence variants into genotypes suggests strong gametic disequilibrium between two MHC class I loci in S. guntheri , and only two haplotypes that were present in Hardy–Weinberg proportions were identified. MHC diversity in NBI tuatara appears to be largely influenced by genetic drift, consistent with a recent population bottleneck. This may compromise the ability of this population to respond to novel disease threats. 相似文献
69.
The appearance of endogenous electromagnetic fields in biological systems is a widely debated issue in modern science. The electrophysiological fields have very tiny intensities and it can be inferred that they are rapidly decreasing with the distance from the generating structure, vanishing at very short distances. This makes very hard their detection using standard experimental methods. However, the existence of fast-moving charged particles in the macromolecules inside both intracellular and extracellular fluids may envisage the generation of localized electric currents as well as the presence of closed loops, which implies the existence of magnetic fields. Moreover, the whole set of oscillatory frequencies of various substances, enzymes, cell membranes, nucleic acids, bioelectrical phenomena generated by the electrical rhythm of coherent groups of cells, cell-to-cell communication among population of host bacteria, forms the increasingly complex hierarchies of electromagnetic signals of different frequencies which cover the living being and represent a fundamental information network controlling the cell metabolism. From this approach emerges the concept of electromagnetic homeostasis: that is, the capability of the human body to maintain the balance of highly complex electromagnetic interactions within, in spite of the external electromagnetic noisy environment. This concept may have an important impact on the actual definitions of heal and disease. 相似文献
70.
C. A. Kreikemeier T. B. Engle K. L. Lucot S. D. Kachman T. E. Burkey D. C. Ciobanu 《Animal genetics》2015,46(2):205-208
Tumor necrosis factor alpha (TNF‐α) is a pro‐inflammatory cytokine with a role in activating adaptive immunity to viral infections. By inhibiting the capacity of plasmacytoid dendritic cells to produce interferon‐α and TNF‐α, porcine circovirus 2 (PCV2) limits the maturation of myeloid dendritic cells and impairs their ability to recognize viral and bacterial antigens. Previously, we reported QTL for viremia and immune response in PCV2‐infected pigs. In this study, we analyzed phenotypic and genetic relationships between TNF‐α protein levels, a potential indicator of predisposition to PCV2 co‐infection, and PCV2 susceptibility. Following experimental challenge with PCV2b, TNF‐α reached the peak at 21 days post‐infection (dpi), at which time a difference was observed between pigs that expressed extreme variation in viremia and growth (P < 0.10). A genome‐wide association study (n = 297) revealed that genotypes of 56 433 SNPs explained 73.9% of the variation in TNF‐α at 21 dpi. Major SNPs were identified on SSC8, SSC10 and SSC14. Haplotypes based on SNPs from a SSC8 (9 Mb) 1‐Mb window were associated with variation in TNF‐α (P < 0.02), IgG (P = 0.05) and IgM (P < 0.13) levels at 21 dpi. Potential overlap of regulatory mechanisms was supported by the correlations between genomic prediction values of TNF‐α and PCV2 antibodies (21 dpi, r > 0.22), viremia (14–21 dpi, P > 0.29) and viral load (r = 0.31, P < 0.0001). Characterization of the QTL regions uncovered genes that could influence variation in TNF‐α levels as well as T‐ and B‐cell development, which can affect disease susceptibility. 相似文献