One foot out the door:Stay/leave ambivalence predicts day-to-day fluctuations in commitment and intentions to end the relationship

Why do some people maintain stable feelings of commitment toward their partners, whereas others’ feelings wax and wane from day to day? The current paper draws insight from decision conflict research suggesting that individuals torn between decision options are particularly susceptible to attitude change. In three samples, we validated a stay/leave ambivalence scale to capture internal conflict about whether to remain in versus exit a relationship. In two dyadic daily experience studies, individuals who felt more ambivalent about their relationships experienced greater daily fluctuation in commitment and breakup contemplation compared to less ambivalent individuals. Ambivalent individuals’ relationship intentions were also more strongly tied to their daily experiences, such that they felt more motivated to stay on days with greater relationship positivity, and more motivated to leave on days with greater relationship negativity. We discuss implications of these results for ambivalent individuals, their partners, and our understanding of stay/leave decision processes

Impact of cardiac interoception cues and confidence on voluntary decisions to make or withhold action in an intentional inhibition task

Interoceptive signals concerning the internal physiological state of the body influence motivational feelings and action decisions. Cardiovascular arousal may facilitate inhibition to mitigate risks of impulsive actions. Baroreceptor discharge at ventricular systole underpins afferent signalling of cardiovascular arousal. In a modified Go/NoGo task, decisions to make or withhold actions on ‘Choose’ trials were not influenced by cardiac phase, nor individual differences in heart rate variability. However, cardiac interoceptive awareness and insight predicted how frequently participants chose to act, and their speed of action: Participants with better awareness and insight tended to withhold actions and respond slower, while those with poorer awareness and insight tended to execute actions and respond faster. Moreover, self-reported trait urgency correlated negatively with intentional inhibition rates. These findings suggest that lower insight into bodily signals is linked to urges to move the body, putatively by engendering noisier sensory input into motor decision processes eliciting reactive behaviour

The iCook 4-H Study: An Intervention and Dissemination Test of a Youth/Adult Out-of-School Program

Objective: To describe outcomes from intervention and dissemination of iCook 4-H. Design: Five-state, community-based participatory research and a randomized, controlled trial followed by a 5-state, nonrandomized dissemination test of the iCook 4-H curriculum with control and treatment groups. Setting: Community and university sites. Participants: Youths aged 9−10 years and their adult food preparer; 228 dyads in the intervention and 74 dyads in dissemination. Intervention(s): Theoretical frameworks were Social Cognitive Theory and the experiential 4-H learning model. Six 2-hour, biweekly sessions on cooking, eating, and playing together followed by monthly newsletters and boosters until 24 months, expanded to 8 sessions for dissemination. Main Outcome Measure(s): Youth body mass index (BMI) z-scores, measured height and weight, and youth/adult program outcome evaluations surveys. Analysis: Linear mixed models, group, time, and group £ time interaction for BMI z-score and program outcomes changes. Significance levels = P ≤ .05; interaction term significance = P ≤ .10. Results: In intervention, treatment BMI z-scores increased compared with controls based on significant interaction (P = .04). For odds of being overweight or obese at 24 months, there was no significant interaction (P = .18). In dissemination, based on significant interaction, treatment youths increased cooking skills (P = .03) and treatment adults increased cooking together (P = .08) and eating together (P = .08) compared with controls. Conclusions and Implications: iCook 4-H program outcomes were positive for mealtime activities of cooking and eating together. The program can be successfully implemented by community educators. The increase in BMI z-scores needs further evaluation for youths in cooking programs

The iCook 4-H Study: An Intervention and Dissemination Test of a Youth/Adult Out-of-School Program

Objective To describe outcomes from intervention and dissemination of iCook 4-H. Design Five-state, community-based participatory research and a randomized, controlled trial followed by a 5-state, nonrandomized dissemination test of the iCook 4-H curriculum with control and treatment groups. Setting Community and university sites. Participants Youths aged 9–10 years and their adult food preparer; 228 dyads in the intervention and 74 dyads in dissemination. Intervention(s) Theoretical frameworks were Social Cognitive Theory and the experiential 4-H learning model. Six 2-hour, biweekly sessions on cooking, eating, and playing together followed by monthly newsletters and boosters until 24 months, expanded to 8 sessions for dissemination. Main Outcome Measure(s) Youth body mass index (BMI) z-scores, measured height and weight, and youth/adult program outcome evaluations surveys. Analysis Linear mixed models, group, time, and group × time interaction for BMI z-score and program outcomes changes. Significance levels = P ≤ .05; interaction term significance = P ≤ .10. Results In intervention, treatment BMI z-scores increased compared with controls based on significant interaction (P = .04). For odds of being overweight or obese at 24 months, there was no significant interaction (P = .18). In dissemination, based on significant interaction, treatment youths increased cooking skills (P = .03) and treatment adults increased cooking together (P = .08) and eating together (P = .08) compared with controls. Conclusions and Implications iCook 4-H program outcomes were positive for mealtime activities of cooking and eating together. The program can be successfully implemented by community educators. The increase in BMI z-scores needs further evaluation for youths in cooking programs

Bats Use Magnetite to Detect the Earth's Magnetic Field

While the role of magnetic cues for compass orientation has been confirmed in numerous animals, the mechanism of detection is still debated. Two hypotheses have been proposed, one based on a light dependent mechanism, apparently used by birds and another based on a “compass organelle” containing the iron oxide particles magnetite (Fe3O4). Bats have recently been shown to use magnetic cues for compass orientation but the method by which they detect the Earth's magnetic field remains unknown. Here we use the classic “Kalmijn-Blakemore” pulse re-magnetization experiment, whereby the polarity of cellular magnetite is reversed. The results demonstrate that the big brown bat Eptesicus fuscus uses single domain magnetite to detect the Earths magnetic field and the response indicates a polarity based receptor. Polarity detection is a prerequisite for the use of magnetite as a compass and suggests that big brown bats use magnetite to detect the magnetic field as a compass. Our results indicate the possibility that sensory cells in bats contain freely rotating magnetite particles, which appears not to be the case in birds. It is crucial that the ultrastructure of the magnetite containing magnetoreceptors is described for our understanding of magnetoreception in animals

Experiment, monitoring, and gradient methods used to infer climate change effects on plant communities yield consistent patterns

Inference about future climate change impacts typically relies on one of three approaches: manipulative experiments, historical comparisons (broadly defined to include monitoring the response to ambient climate fluctuations using repeat sampling of plots, dendroecology, and paleoecology techniques), and space-for-time substitutions derived from sampling along environmental gradients. Potential limitations of all three approaches are recognized. Here we address the congruence among these three main approaches by comparing the degree to which tundra plant community composition changes (i) in response to in situ experimental warming, (ii) with interannual variability in summer temperature within sites, and (iii) over spatial gradients in summer temperature. We analyzed changes in plant community composition from repeat sampling (85 plant communities in 28 regions) and experimental warming studies (28 experiments in 14 regions) throughout arctic and alpine North America and Europe. Increases in the relative abundance of species with a warmer thermal niche were observed in response to warmer summer temperatures using all three methods; however, effect sizes were greater over broad-scale spatial gradients relative to either temporal variability in summer temperature within a site or summer temperature increases induced by experimental warming. The effect sizes for change over time within a site and with experimental warming were nearly identical. These results support the view that inferences based on space-for-time substitution overestimate the magnitude of responses to contemporary climate warming, because spatial gradients reflect long-term processes. In contrast, in situ experimental warming and monitoring approaches yield consistent estimates of the magnitude of response of plant communities to climate warming

Adaptive divergence despite strong genetic drift: genomic analysis of the evolutionary mechanisms causing genetic differentiation in the island fox (\u3ci\u3eUrocyon littoralis\u3c/i\u3e)

The evolutionary mechanisms generating the tremendous biodiversity of islands have long fascinated evolutionary biologists. Genetic drift and divergent selection are pre- dicted to be strong on islands and both could drive population divergence and specia- tion. Alternatively, strong genetic drift may preclude adaptation. We conducted a genomic analysis to test the roles of genetic drift and divergent selection in causing genetic differentiation among populations of the island fox (Urocyon littoralis). This species consists of six subspecies, each of which occupies a different California Chan- nel Island. Analysis of 5293 SNP loci generated using Restriction-site Associated DNA (RAD) sequencing found support for genetic drift as the dominant evolutionary mech- anism driving population divergence among island fox populations. In particular, pop- ulations had exceptionally low genetic variation, small Ne (range = 2.1–89.7; median = 19.4), and significant genetic signatures of bottlenecks. Moreover, islands with the lowest genetic variation (and, by inference, the strongest historical genetic drift) were most genetically differentiated from mainland grey foxes, and vice versa, indicating genetic drift drives genome-wide divergence. Nonetheless, outlier tests identified 3.6–6.6% of loci as high FST outliers, suggesting that despite strong genetic drift, divergent selection contributes to population divergence. Patterns of similarity among populations based on high FST outliers mirrored patterns based on morphology, providing additional evidence that outliers reflect adaptive divergence. Extremely low genetic variation and small Ne in some island fox populations, particularly on San Nicolas Island, suggest that they may be vulnerable to fixation of deleterious alleles, decreased fitness and reduced adaptive potential

BioTIME: A database of biodiversity time series for the Anthropocene.

MotivationThe BioTIME database contains raw data on species identities and abundances in ecological assemblages through time. These data enable users to calculate temporal trends in biodiversity within and amongst assemblages using a broad range of metrics. BioTIME is being developed as a community-led open-source database of biodiversity time series. Our goal is to accelerate and facilitate quantitative analysis of temporal patterns of biodiversity in the Anthropocene.Main types of variables includedThe database contains 8,777,413 species abundance records, from assemblages consistently sampled for a minimum of 2 years, which need not necessarily be consecutive. In addition, the database contains metadata relating to sampling methodology and contextual information about each record.Spatial location and grainBioTIME is a global database of 547,161 unique sampling locations spanning the marine, freshwater and terrestrial realms. Grain size varies across datasets from 0.0000000158 km2 (158 cm2) to 100 km2 (1,000,000,000,000 cm2).Time period and grainBioTIME records span from 1874 to 2016. The minimal temporal grain across all datasets in BioTIME is a year.Major taxa and level of measurementBioTIME includes data from 44,440 species across the plant and animal kingdoms, ranging from plants, plankton and terrestrial invertebrates to small and large vertebrates.Software format.csv and .SQL

Low pH enhances the action of maximin H5 against Staphylococcus aureus and helps mediate lysylated phosphatidylglycerol induced resistance

Maximin H5 (MH5) is an amphibian antimicrobial peptide specifically targeting Staphylococcus aureus. At pH 6, the peptide showed an increased ability to penetrate (∆П = 6.2 mN m-1) and lyse (lysis = 48 %) S. aureus membrane mimics, which incorporated physiological levels of lysylated phosphatidylglycerol (Lys-PG, 60 %) as compared to pH 7 (∆П = 5.6 mN m-1 and lysis = 40 % at pH 7) where levels of Lys-PG are lower (40 %). The peptide therefore appears to have optimal function at pH levels known to be optimal for the organism’s growth. MH5 killed S. aureus (minimum inhibitory concentration = 90 µM) via membranolytic mechanisms that involved the stabilization of α-helical structure (circa 45-50 %) and which showed similarities to the ‘Carpet’ mechanism based on its ability to increase the rigidity (Cs-1 = 109.94 mN m-1) and thermodynamic stability (∆Gmix = -3.0) of physiologically relevant S. aureus membrane mimics at pH 6. Based on theoretical analysis this mechanism may involve the use of a tilted peptide structure and efficacy was noted to vary inversely with the Lys-PG content of S. aureus membrane mimics for each pH studied (R2 circa 0.97), which led to the suggestion that under biologically relevant conditions, low pH helps mediate Lys-PG induced resistance in S. aureus to MH5 antibacterial action. The peptide showed a lack of haemolytic activity (< 2 % haemolysis) and merits further investigation as a potential template for development as an anti-staphylococcal agent in medically and biotechnically relevant areas

Masses, radii, and orbits of small Kepler planets : The transition from gaseous to rocky planets

We report on the masses, sizes, and orbits of the planets orbiting 22 Kepler stars. There are 49 planet candidates around these stars, including 42 detected through transits and 7 revealed by precise Doppler measurements of the host stars. Based on an analysis of the Kepler brightness measurements, along with high-resolution imaging and spectroscopy, Doppler spectroscopy, and (for 11 stars) asteroseismology, we establish low false-positive probabilities (FPPs) for all of the transiting planets (41 of 42 have an FPP under 1%), and we constrain their sizes and masses. Most of the transiting planets are smaller than three times the size of Earth. For 16 planets, the Doppler signal was securely detected, providing a direct measurement of the planet's mass. For the other 26 planets we provide either marginal mass measurements or upper limits to their masses and densities; in many cases we can rule out a rocky composition. We identify six planets with densities above 5 g cm-3, suggesting a mostly rocky interior for them. Indeed, the only planets that are compatible with a purely rocky composition are smaller than 2 R ⊕. Larger planets evidently contain a larger fraction of low-density material (H, He, and H2O).Peer reviewedFinal Accepted Versio