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891.
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Melanoma is responsible for the majority of deaths related to skin cancer. Worryingly, prognoses show an increasing number of melanoma cases each year worldwide. Radiotherapy, which is a cornerstone of cancer treatment, has proved to be useful but insufficient in melanoma management due to exceptionally high radioresistance of melanoma cells. This problem could be overcome by superparamagnetic iron oxide nanoparticles (SPIONs) used as heat mediators in magnetic hyperthermia, which not only enhance radiosensitivity, but also enable precise targeting by exploitation of their magnetic properties.  相似文献   
894.
Hybrid zones between divergent populations sieve genomes into blocks that introgress across the zone, and blocks that do not, depending on selection between interacting genes. Consistent with Haldane's rule, the Y chromosome has been considered counterselected and hence not to introgress across the European house mouse hybrid zone. However, recent studies detected massive invasion of M. m. musculus Y chromosomes into M. m. domesticus territory. To understand mechanisms facilitating Y spread, we created 31 recombinant lines from eight wild‐derived strains representing four localities within the two mouse subspecies. These lines were reciprocally crossed and resulting F1 hybrid males scored for five phenotypic traits associated with male fitness. Molecular analyses of 51 Y‐linked SNPs attributed ~50% of genetic variation to differences between the subspecies and 8% to differentiation within both taxa. A striking proportion, 21% (frequencies of sperm head abnormalities) and 42% (frequencies of sperm tail dissociations), of phenotypic variation was explained by geographic Y chromosome variants. Our crossing design allowed this explanatory power to be examined across a hierarchical scale from subspecific to local intrastrain effects. We found that divergence and variation were expressed diversely in different phenotypic traits and varied across the whole hierarchical scale. This finding adds another dimension of complexity to studies of Y introgression not only across the house mouse hybrid zone but potentially also in other contact zones.  相似文献   
895.
Two Orthotrichum species of the subgenus Orthophyllum were compared with other representatives of this genus using internally transcribed spacer regions 1 and 2, the chloroplast trn H-psbA region, and inter-simple sequence repeat (ISSR) and intron-exon splice conjunction (ISJ) markers. The ISSR and ISJ markers used revealed many bands and mutations specific only to O. Gymnostomum and O. Obtusifolium. Phylogenetic analysis clearly supported previous concepts postulating that species of the subgenus Orthophyllum should be recognized as the separate genus Nyholmiella.  相似文献   
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Journal of Mathematical Biology - The transfer distance (TD) was introduced in the classification framework and studied in the context of phylogenetic tree matching. Recently, Lemoine et al....  相似文献   
898.
A long range surface plasmon (LRSP) is an electromagnetic wave propagating along a thin metal film with an order of magnitude lower damping than conventional surface plasmon (SP) waves. Thus, the excitation of LRSP is associated with a narrower resonance and it provides larger enhancement of intensity of the electromagnetic field. In surface plasmon resonance (SPR) biosensors, these features allow a more precise observation of the binding of biomolecules in the proximity to the metal surface by using the (label-free) measurement of refractive index (RI) variations and by SP-enhanced fluorescence spectroscopy. In this contribution, we investigate LRSPs excited on a layer structure consisting of a fluoropolymer buffer layer, a thin gold film, and an aqueous sample. By implementing such structure in an SPR sensor, we achieved a 2.4- and 4.4-fold improvement of the resolution in the label-free and fluorescence-based detection, respectively, of the binding of biomolecules in the close proximity to the surface. Moreover, we demonstrate that the sensor resolution can be improved by a factor of 14 and 12 for the label-free and fluorescence-based detection, respectively, if the biomolecular binding events occur within the whole evanescent field of LRSP.  相似文献   
899.
In capture–recapture models, survival and capture probabilities can be modelled as functions of time‐varying covariates, such as temperature or rainfall. The Cormack–Jolly–Seber (CJS) model allows for flexible modelling of these covariates; however, the functional relationship may not be linear. We extend the CJS model by semi‐parametrically modelling capture and survival probabilities using a frequentist approach via P‐splines techniques. We investigate the performance of the estimators by conducting simulation studies. We also apply and compare these models with known semi‐parametric Bayesian approaches on simulated and real data sets.  相似文献   
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