Concurrent Self Research Articles

The development of prosocial moral reasoning and a prosocial orientation in young adulthood: Concurrent and longitudinal correlates.

We examined stability and change in prosocial moral reasoning (PRM) assessed longitudinally at ages 20/21, 22/23, 24/25, 26/27, and 31/32 years (N = 32; 16 female) using a pencil-and-paper measure of moral reasoning and examined relations of PRM and prosocial behavior with one another and with empathy, sympathy measured with self- and friend reports in adulthood, self- and mother reports of prosocial tendencies in adolescence, and observed prosocial behavior in preschool. Proportions of different types of PRM (hedonistic, approval, stereotypic, internalized) exhibited high mean-level stability across early adulthood, although stereotypic PMR increased with age and hedonistic PRM (a less sophisticated type of PRM) declined over time for males. More sophisticated PMR was positively related to friends' reports of a prosocial orientation concurrently and at age 24/25, as well as self-reports of sympathy in adolescence. Specific modes of PMR related to spontaneous or compliant sharing in preschool. Women used more sophisticated PMR than men across the entire study period. Self-reported and friend-reported prosociality at age 27/28 and 31/32 (combined) was related to numerous prior measures of a prosocial orientation, including spontaneous, relatively costly prosocial behavior in preschool (for self-reports and friend-reported sympathy/consideration for others). Donating/volunteering at T13/T14 was related to concurrent self- and friend-reported prosociality and to self-reported prosocial orientation in earlier adulthood and mother-reported helping in adolescence.

Lower Bounds and Impossibility Results for Concurrent Self Composition

In the setting of concurrent self composition, a single protocol is executed many times concurrently in a network. In this paper, we prove lower bounds and impossibility results for secure protocols in this setting. First and foremost, we prove that there exist large classes of functionalities that cannot be securely computed under concurrent self composition, by any protocol. We also prove a communication complexity lower bound on protocols that securely compute a large class of functionalities in this setting. Specifically, we show that any protocol that computes a functionality from this class and remains secure for m concurrent executions, must have bandwidth of at least m bits. The above results are unconditional and hold for any type of simulation (i.e., even for non-black-box simulation). In addition, we prove a severe lower bound on protocols that are proven secure using black-box simulation. Specifically, we show that any protocol that computes the blind signature or oblivious transfer functionalities and remains secure for m concurrent executions, where security is proven via black-box simulation, must have at least m rounds of communication. Our results hold for the plain model, where no trusted setup phase is assumed. While proving our impossibility results, we also show that for many functionalities, security under concurrent self composition (where a single secure protocol is run many times) is actually equivalent to the seemingly more stringent requirement of security under concurrent general composition (where a secure protocol is run concurrently with other arbitrary protocols). This observation has significance beyond the impossibility results that are derived by it for concurrent self composition.

Correlated Evolution in Floral Morphology and the Timing of Self‐Compatibility inLeptosiphon jepsonii(Polemoniaceae)

The timing of self‐compatibility was found to vary within and among populations of Leptosiphon jepsonii, a narrowly distributed California annual species. In each of 17 populations, some individuals exhibited transient self‐incompatibility, a phenomenon that confers delayed selfing, while others were fully self‐compatible upon flower opening, allowing for concurrent self‐ and cross‐fertilization. The frequency of initially self‐compatible individuals varied significantly among populations, ranging from 3.2% to 71.0%. A comparison of outcrossing rate estimates for three populations was consistent with the hypothesis that early self‐compatibility promotes higher selfing rates. Population means for each of three floral morphological traits were significantly correlated with a population index of self‐incompatibility that reflects the frequency of fully self‐compatible and transiently self‐incompatible individuals. A high frequency of self‐compatibility was associated with shorter corolla tubes, smaller corol...

Ovule pre-emption and pollen limitation in a self-fertile perennial herb (Blandfordia grandiflora, Liliaceae).

The extent, frequency and causes of pollenlimited seed production were examined in partially selffertile populations of Blandfordia grandiflora for 2 years. Percentage seed set of open-pollinated plants (50-57%) did not differ within or between years, and was about 19% less than experimentally cross-pollinated plants (70-75%). Floral visits by honeybees did not differ through the flowering season and the number of pollen grains deposited on stigmas within 12 h of flowers opening exceeded the number of ovules per flower, indicating that the quality rather than the quantity of pollination limited seed set. Pollen limitation was caused by concurrent self- and cross-pollination and the subsequent abortion of some selfed ovules due to inbreeding depression. Natural seed set (55%) was intermediate between selfed (43%) and crossed (75%) flowers and was not increased when flowers that had been available to pollinators for 24 h were hand cross-pollinated, suggesting that ovules were already fertilized. Similarly, experimental pollination with both cross and self pollen within 24 h of flowers opening did not increase seed set relative to natural seed set, indicating that both cross- and self-fertilizations had occurred. In contrast, when selfing followed crossing by 48 h, or vice versa, seed set did not differ from crossed-only or selfed-only flowers, respectively, indicating that ovules were pre-empted by the first pollination. Collectively, these results indicate that under natural conditions self pollen pre-empts ovules, rendering them unavailable for cross-fertilization. This selfing reduces fecundity by 50%, as estimated from the natural production of cross seeds when selfing was prevented. Consequently, selection should favour floral traits, such as increased stigma-anther separation or protandry, that reduce interference between male and female functions that leads to selfing.