Volunteer involvement in biological surveys is becoming common in conservation and ecology, prompting questions on the quality of data collected in such surveys. In a systematic review of the peer-reviewed literature on the quality of data collected by volunteers, we examined the characteristics of volunteers (e.g., age, prior knowledge) and projects (e.g., systematic vs. opportunistic monitoring schemes) that affect data quality with regards to standardization of sampling, accuracy and precision of data collection, spatial and temporal representation of data, and sample size. Most studies (70%, n = 71) focused on the act of data collection. The majority of assessments of volunteer characteristics (58%, n = 93) examined the effect of prior knowledge and experience on quality of the data collected, often by comparing volunteers with experts or professionals, who were usually assumed to collect higher quality data. However, when both groups' data were compared with the same accuracy standard, professional data were more accurate in only 4 of 7 cases. The few studies that measured precision of volunteer and professional data did not conclusively show that professional data were less variable than volunteer data. To improve data quality, studies recommended changes to survey protocols, volunteer training, statistical analyses, and project structure (e.g., volunteer recruitment and retention).
Most small cell lung cancer (SCLC) patients relapse within 12 months of starting combination chemotherapy plus radio-therapy, due to the development of acquired chemo-and radio-resistance. This phenomenon relates to the induction of tumour differentiation, resulting in apoptosis-resistant, morphologically variant (v-SCLC) cells, which lack the neuroendocrine expression of classic (c-) SCLC cells. In this study spontaneously adherent SCLC sublines were shown by differential gene expression analysis to provide an in vitro model of variant differentiation in SCLC, with down-regulation of neuroendocrine markers and up-regulation of epithelial differentiation markers cyclin D1, endothelin, the cell adhesion molecules CD 44 and integrin subunits a2, b3 and b4. The sensitivity of adherent SCLC sublines to etoposide, cyclophosphamide and gamma radiation was significantly diminished relative to parent suspension cell lines. Western blot analysis using phosphorylationspecific antibodies to Akt and MAP kinase revealed markedly elevated activation in adherent SCLC sublines, paralleled by increased levels of phosphorylated Bad protein and activated NF-kB. Subcultivation of the adherent sublines on uncoated surfaces reversed their adherent phenotype immediately and under these conditions Akt activity reverted to low levels. These results suggest that c-SCLC cells can differentiate spontaneously to v-SCLC and that the associated cellular adhesion may trigger Akt-dependent inhibition of apoptosis in SCLC cells, thus leading to acquired chemoand radio-resistance.
Fecundity estimates for demographic modelling are difficult to acquire at the regional spatial scales that correspond to climate shifts, land use impacts or habitat management programmes. Yet they are important for evaluating such effects. While waterfowl managers have historically used harvest‐based age ratios to assess fecundity at continental scales, widely available age ratios from late summer banding (ringing) data present an underutilized opportunity to examine a regional fecundity index with broad temporal replication. We used age ratios from banding data and hierarchical mixed‐effect models to examine how fecundity of five North American dabbling duck species was affected by temporal variation in hydrological cycles, intra‐ and interspecific density dependence and alternate prey availability, and whether those relationships were consistent across a broad geographic area. Model‐estimated fecundity was within the range of traditional harvest‐based fecundity estimates for each species. Ecological covariates explained between 16% and 53% of the temporal variation in fecundity, dependent on species. Increasing wetland inundation and an indicator of vole population irruptions were consistent predictors of increasing fecundity across all species. Species exhibited mixed positive and negative responses to interspecific and intraspecific breeding pair densities hypothesized to affect nest and brood survival respectively, highlighting the importance of integrating brood survival into fecundity metrics for precocial species. Declines in fecundity over time and across space at more northern latitudes may reflect stronger policies for grassland and wetland protection in the U.S. versus Canadian portions of the prairies over the time period of our study. Maintaining the capacity of less permanent basins to rehydrate in wetter periods through easement protection benefits fecundity, particularly for late‐nesting species that acquire a greater proportion of their reproductive energy on the breeding grounds. Synthesis and applications. Age ratios derived from postbreeding banding operations allowed us to attribute variation in waterfowl fecundity to temporal ecological variables. Effects of habitat management for waterfowl may be masked unless analysts account for this temporal variation. Postbreeding‐pulse age ratios at capture could be useful as fecundity metrics in integrated population models and for evaluating population dynamics of extensively banded nongame species, especially if adjusted for capture vulnerability using within‐season recapture data.
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