Adoption behaviour by gulls: a new hypothesis

It appears that chicks are selected to run away and seek adoption in a foster-family when the level of investment they receive falls below a certain threshold. Predictions based on this hypothesis are in agreement with the available evidence in the literature.     

Role of β1 Integrins in Cell Spreading and Migration of Human Nevomelanocytes and Dysplastic Nevi Cells on Collagen Type IV and Laminin

We characterized β1 integrin subunit expression on three different cultures of benign human nevomelanocytes (NMC) and on four different cell cultures of human dysplastic nevus (DN) cells by flow cytometry analysis and examined their role in mediating cell spreading and migration on collagen type IV (CN IV) and laminin (LN) coated substrates by using a quantitative video image analysis system. The seven human NMC and DNC cultures expressed heterogeneous levels of β1, α2, α3 and α6 integrin subunits. Image analysis showed that a significant increase (P<0.001) in cell spreading and migration of the DN cells was induced on increasing coating concentrations of CN IV and LN. However, the NMC did not show an increase in cell spreading or migration on these substrates when compared to the substrates coated with denatured BSA only. The CN IV-induced cell spreading of the DN cells was significantly inhibited by anti-β1 mAb (AIIB2), anti-α2 mAb (P1E6), or anti-α3 mAb (P1B5), but not by mAb against α6 integrin subunit (GoH3). The DN cell spreading on LN was not significantly inhibited by these mAbs. In contrast, the migration of the DN on CN IV and LN was significantly inhibited by anti-β1 mAb, anti-α2 mAb, anti-α3 mAb and anti-α6 mAb. These data suggest that the α2 and α3 subunit are important for cell spreading of the DN on CN IV, although they are less important in cell spreading on the extracellular matrix component LN. The α2, α3 and α6 integrin subunits are important for the migration of DN cells on both CN IV and LN.     

Impacts of Hurricane Frances on Florida scrub-oak ecosystem processes: defoliation, net CO2 exchange and interactions with elevated CO2

Hurricane disturbances have profound impacts on ecosystem structure and function, yet their effects on ecosystem CO₂ exchange have not been reported. In September 2004, our research site on a fire‐regenerated scrub‐oak ecosystem in central Florida was struck by Hurricane Frances with sustained winds of 113 km h⁻¹ and wind gusts as high as 152 km h⁻¹. We quantified the hurricane damage on this ecosystem resulting from defoliation: we measured net ecosystem CO₂ exchange, the damage and recovery of leaf area, and determined whether growth in elevated carbon dioxide concentration in the atmosphere (C_a) altered this disturbance. The hurricane decreased leaf area index (LAI) by 21%, which was equal to 60% of seasonal variation in canopy growth during the previous 3 years, but stem damage was negligible. The reduction in LAI led to a 22% decline in gross primary production (GPP) and a 25% decline in ecosystem respiration (R_e). The compensatory declines in GPP and R_e resulted in no significant change in net ecosystem production (NEP). Refoliation began within a month after the hurricane, although this period was out of phase with the regular foliation period, and recovered 20% of the defoliation loss within 2.5 months. Full recovery of LAI, ecosystem CO₂ assimilation, and ecosystem respiration did not occur until the next growing season. Plants exposed to elevated C_a did not sustain greater damage, nor did they recover faster than plants grown under ambient C_a. Thus, our results indicate that hurricanes capable of causing significant defoliation with negligible damage to stems have negligible effects on NEP under current or future CO₂‐enriched environment.     

WHAT SENSORY CHARACTERISTICS DRIVE PRODUCT QUALITY? AN ASSESSMENT OF INDIVIDUAL DIFFERENCES

Consumers differ dramatically in their sensory preferences for products. This paper assesses the relative importance of appearance, taste/flavor and texture as characteristics that drive acceptance for a complex pie product. The paper classifies consumers as being driven by one or more sensory attributes in their judgment of product quality. To do so, each consumer's liking rating is regressed against each separate attribute liking. The coefficient (M) of the linear equation "Overall Liking = M (Attribute Liking) + B" measures the relative importance of the sensory attribute as a driver of overall quality.     

Salinity and sea level mediate elevated CO2 effects on C3–C4 plant interactions and tissue nitrogen in a Chesapeake Bay tidal wetland

Elevated atmospheric carbon dioxide concentrations ([CO₂]) generally increase plant photosynthesis in C₃ species, but not in C₄ species, and reduce stomatal conductance in both C₃ and C₄ plants. In addition, tissue nitrogen concentration ([N]) often fails to keep pace with enhanced carbon gain under elevated CO₂, particularly in C₃ species. While these responses are well documented in many species, implications for plant growth and nutrient cycling in native ecosystems are not clear. Here we present data on 18 years of measurement of above and belowground biomass, tissue [N] and total standing crop of N for a Scirpus olneyi‐dominated (C₃ sedge) community, a Spartina patens‐dominated (C₄ grass) community and a C₃–C₄‐mixed species community exposed to ambient and elevated (ambient +340 ppm) atmospheric [CO₂] in natural salinity and sea level conditions of a Chesapeake Bay wetland. Increased biomass production (shoots plus roots) under elevated [CO₂] in the S. olneyi‐dominated community was sustained throughout the study, averaging approximately 35%, while no significant effect of elevated [CO₂] was found for total biomass in the C₄‐dominated community. We found a significant decline in C₄ biomass (correlated with rising sea level) and a concomitant increase in C₃ biomass in the mixed community. This shift from C₄ to C₃ was accelerated by the elevated [CO₂] treatment. The elevated [CO₂] stimulation of total biomass accumulation was greatest during rainy, low salinity years: the average increase above the ambient treatment during the three wettest years (1994, 1996, 2003) was 2.9 t ha⁻¹ but in the three driest years (1995, 1999, 2002), it was 1.2 t ha⁻¹. Elevated [CO₂] depressed tissue [N] in both species, but especially in the S. olneyi where the relative depression was positively correlated with salinity and negatively related with the relative enhancement of total biomass production. Thus, the greatest amount of carbon was added to the S. olneyi‐dominated community during years when shoot [N] was reduced the most, suggesting that the availability of N was not the most or even the main limitation to elevated [CO₂] stimulation of carbon accumulation in this ecosystem.     

EMPIRICAL ETHICS AS DIALOGICAL PRACTICE

In this article, we present a dialogical approach to empirical ethics, based upon hermeneutic ethics and responsive evaluation. Hermeneutic ethics regards experience as the concrete source of moral wisdom. In order to gain a good understanding of moral issues, concrete detailed experiences and perspectives need to be exchanged. Within hermeneutic ethics dialogue is seen as a vehicle for moral learning and developing normative conclusions. Dialogue stands for a specific view on moral epistemology and methodological criteria for moral inquiry. Responsive evaluation involves a structured way of setting up dialogical learning processes, by eliciting stories of participants, exchanging experiences in (homogeneous and heterogeneous) groups and drawing normative conclusions for practice. By combining these traditions we develop both a theoretical and a practical approach to empirical ethics, in which ethical issues are addressed and shaped together with stakeholders in practice. Stakeholders' experiences are not only used as a source for reflection by the ethicist; stakeholders are involved in the process of reflection and analysis, which takes place in a dialogue between participants in practice, facilitated by the ethicist. This dialogical approach to empirical ethics may give rise to questions such as: What contribution does the ethicist make? What role does ethical theory play? What is the relationship between empirical research and ethical theory in the dialogical process? In this article, these questions will be addressed by reflecting upon a project in empirical ethics that was set up in a dialogical way. The aim of this project was to develop and implement normative guidelines with and within practice, in order to improve the practice concerning coercion and compulsion in psychiatry.     

How a bottom‐dweller beats the canopy: inhibition of an aquatic weed (Potamogeton pectinatus) by macroalgae (Chara spp.)

1. Bottom‐dwelling charophytes have been observed to replace canopy‐forming pondweeds within a few years in de‐eutrophied shallow lakes. Competition for bicarbonate (HCO₃^?) may explain this shift in vegetation dominance but inhibition of pondweeds by Chara spp. through direct competition has not been shown experimentally. 2. We tested whether charophytes inhibited growth of fennel pondweed (Potamogeton pectinatus) in the absence of belowground competition by growing plants in pots in mesocosms following a replacement series experimental design. To further understand the role of bicarbonate, we studied main and interactive effects of Chara, light and bicarbonate on P. pectinatus growth in a laboratory study. 3. Early in the mesocosm experiment, high charophyte densities had a negative effect on P. pectinatus cover at a time when bicarbonate levels were low. However, bicarbonate levels eventually converged to low levels in all treatments. At final harvest, both species exhibited lower biomasses at higher densities of conspecific pots, indicating that ultimately intraspecific competition was limiting. In a laboratory study, Chara inhibited P. pectinatus the most under a combination of high light and high bicarbonate concentrations, suggesting that Chara may negatively affect P. pectinatus by acting as a general nutrient sink. 4. Our results suggest that Chara growth can reduce bicarbonate levels, delaying but not preventing a P. pectinatus growth pulse. Given the recorded inhibition under ample bicarbonate supply, Chara’s ability to act as nutrient sink may contribute to the decline of P. pectinatus under Chara recovery in shallow lakes.     

THE ONGOING CHARITY OF ORGAN DONATION. CONTEMPORARY ENGLISH SUNNI FATWAS ON ORGAN DONATION AND BLOOD TRANSFUSION

Background: Empirical studies in Muslim communities on organ donation and blood transfusion show that Muslim counsellors play an important role in the decision process. Despite the emerging importance of online English Sunni fatwas, these fatwas on organ donation and blood transfusion have hardly been studied, thus creating a gap in our knowledge of contemporary Islamic views on the subject. Method: We analysed 70 English Sunni e‐fatwas and subjected them to an in‐depth text analysis in order to reveal the key concepts in the Islamic ethical framework regarding organ donation and blood transfusion. Results: All 70 fatwas allow for organ donation and blood transfusion. Autotransplantation is no problem at all if done for medical reasons. Allotransplantation, both from a living and a dead donor, appears to be possible though only in quite restricted ways. Xenotransplantation is less often mentioned but can be allowed in case of necessity. Transplantation in general is seen as an ongoing form of charity. Nearly half of the fatwas allowing blood transfusion do so without mentioning any restriction or problem whatsoever. The other half of the fatwas on transfusion contain the same conditional approval as found in the arguments pro organ transplantation. Conclusion: Our findings are very much in line with the international literature on the subject. We found two new elements: debates on the definition of the moment of death are hardly mentioned in the English Sunni fatwas and organ donation and blood transfusion are presented as an ongoing form of charity.     

Sibship reconstruction demonstrates the extremely low effective population size of striped bass Morone saxatilis in the Santee–Cooper system, South Carolina, USA

For organisms with great fecundity and high mortality in early life stages, such as shellfish or fishes, the need to match reproductive activity with environmental conditions conducive to spawning, fertilization, larval development and recruitment may result in extreme variance in reproductive success among individuals. The main objective of this study was to investigate evidence of large variance in the reproductive success of the striped bass Morone saxatilis in the Santee–Cooper system, South Carolina, USA. Seven microsatellite loci were analysed in 603 recruits representing three yearly cohorts from 1992 to 1994, and a group analysis was performed to identify full-sib families. Large variance in reproductive success was detected, with a few large, full-sib families contributing disproportionately to each of the cohorts. The severity of sweepstakes reproductive success varied among cohorts depending on environmentally imposed mortality. Estimations of the effective number of breeders in these long-lived fish ranged from 24 in 1992 to 44 in 1994. Furthermore, the estimated genetic effective population size ( N _e = 93) is approximately four orders of magnitude lower than estimates of adult census size ( N  =   362 000). Furthermore, the presence of large full-sib families indicates that striped bass engage in pair mating in the wild. Heterogeneity in genetic composition was also observed among cohorts, suggesting that genetically different adults contribute to different cohorts and that chance rather than fitness variation determines reproductive success.