Evaluation of grapevine water status from trunk diameter variations

We evaluated the usefulness of short-term trunk diameter variations (TDV) as water stress indicator in field-grown grapevines cv. Tempranillo. Two indices were calculated from TDV, maximum daily trunk shrinkage (MDS), and trunk growth rate (TGR). The seasonal evolution of both indicators was compared with occasional determinations of pre-dawn leaf water potential and stem water potential, measured at early morning (Ψ s em ) and at midday (Ψ s md ) in irrigated and non-irrigated vines. In the second season, the effect of crop load on the vine water status indicators was also studied. Crop load did not affect either the vine water relations or the TDV. All water potential determinations had much lower variability and were more sensitive than both MDS and TGR to water restrictions. The ability of both indices to detect plant water stress varied largely depending upon the phenological period. In fact, MDS and TGR were only able to detect vine water stress during a short period of time before veraison. During this period, TGR was linearly related to both Ψ s em and Ψ s md , while for MDS a curvilinear, quadratic equation, better described the relationship with plant water status. After veraison no apparent relationship existed between plant water status and MDS or TGR. Hence, our results question the practical use of both MDS and TGR as variables to automate irrigation scheduling for grapevin

Frequency and power dependence of spin-current emission by spin pumping in a thin film YIG/Pt system

This paper presents the frequency dependence of the spin current emission in a hybrid ferrimagnetic insulator/normal metal system. The system is based on a ferrimagnetic insulating thin film of Yttrium Iron Garnet (YIG, 200 nm) grown by liquid-phase-epitaxy (LPE) coupled with a normal metal with a strong spin-orbit coupling (Pt, 15 nm). The YIG layer presents an isotropic behaviour of the magnetization in the plane, a small linewidth, and a roughness lower than 0.4 nm. Here we discuss how the voltage signal from the spin current detector depends on the frequency [0.6 - 7 GHz], the microwave power, Pin, [1 - 70 mW], and the in-plane static magnetic field. A strong enhancement of the spin current emission is observed at low frequencies, showing the appearance of non-linear phenomena.Comment: 7 pages, 5 figure

Memory for allergies and health foods: how younger and older adults strategically remember critical health information

Objectives. While older adults often display memory deficits, with practice they can sometimes selectively remember valuable information at the expense of less value information. We examined age-related differences and similarities in memory for health-related information under conditions where some information was critical to remember. Method. In Experiment 1, participants studied three lists of allergens, ranging in severity from 0 (not a health risk) to 10 (potentially fatal), with the instruction that it was particularly important to remember items to which a fictional relative was most severely allergic. After each list, participants received feedback regarding their recall of the high-value allergens. Experiment 2 examined memory for health benefits, presenting foods that were potentially beneficial to the relative’s immune system. Results. While younger adults exhibited better overall memory for the allergens, both age groups in Experiment 1 developed improved selectivity across the lists, with no evident age differences in severe allergen recall by List 2. Selectivity also developed in Experiment 2, although age differences for items of high health benefit were present. Discussion. The results have implications for models of selective memory in older age, and for how aging influences the ability to strategically remember important information within health-related contexts

Free recall test experience potentiates strategy-driven effects of value on memory.

People tend to show better memory for information that is deemed valuable or important. By one mechanism, individuals selectively engage deeper, semantic encoding strategies for high value items (Cohen, Rissman, Suthana, Castel, & Knowlton, 2014). By another mechanism, information paired with value or reward is automatically strengthened in memory via dopaminergic projections from midbrain to hippocampus (Shohamy & Adcock, 2010). We hypothesized that the latter mechanism would primarily enhance recollection-based memory, while the former mechanism would strengthen both recollection and familiarity. We also hypothesized that providing interspersed tests during study is a key to encouraging selective engagement of strategies. To test these hypotheses, we presented participants with sets of words, and each word was associated with a high or low point value. In some experiments, free recall tests were given after each list. In all experiments, a recognition test was administered 5 minutes after the final word list. Process dissociation was accomplished via remember/know judgments at recognition, a recall test probing both item memory and memory for a contextual detail (word plurality), and a task dissociation combining a recognition test for plurality (intended to probe recollection) with a speeded item recognition test (to probe familiarity). When recall tests were administered after study lists, high value strengthened both recollection and familiarity. When memory was not tested after each study list, but rather only at the end, value increased recollection but not familiarity. These dual process dissociations suggest that interspersed recall tests guide learners' use of metacognitive control to selectively apply effective encoding strategies. (PsycINFO Database Recor

Vine and soil-based measures of water status in a Tempranillo vineyard

Seasonal changes of leaf and stem water potential and midday stomatal conductance (gs) of Tempranillo grapevines were determined in irrigated and non-irrigated vines in 2003 and 2004. Leaf water potential was measured at pre-dawn (Ψpd) and at midday (Ψlmd), while stem water potential was measured in the early morning (Ψsem) and at midday (Ψsmd). At Ψpd to -0.54 MPa rain-fed and irrigated vines had similar midday Ψl and Ψs. This was due to both, stomatal closure and reduction of leaf area. Under these conditions, Ψpd and Ψsem were better water stress indicators than midday Ψ. In both years a close correlation was found between Ψpd and Ψsem. However, for a given Ψpd, Ψsem of vines was lower in 2004 than in 2003. This was probably due to the larger leaf area developed by vines in 2004. Stomatal conductance reflected reasonably well differences in the vine water status but its variability was much higher than that of Ψ. Moreover, the afternoon depression of stomatal conductance observed even in irrigated plots, indicates that measuring gs early in the morning is more convenient when assessing different treatments.

Mastery-approach goals eliminate retrieval-induced forgetting: the role of achievement goals in memory inhibition

The present study examined how achievement goals affect retrieval-induced forgetting. Researchers have suggested that mastery-approach goals (i.e., developing one’s own competence) promote a relational encoding, whereas performance-approach goals (i.e., demonstrating one’s ability in comparison to others) promote item-specific encoding. These different encoding processes may affect the degree to which participants integrate the exemplars within a category and, as a result, we expected that retrieval-induced forgetting may be reduced or eliminated under mastery-approach goals. Three experiments were conducted using a retrieval-practice paradigm with different stimuli, where participants’ achievement goals were manipulated through brief written instructions. A meta-analysis that synthesized the results of the three experiments showed that retrieval-induced forgetting was not statistically significant in the mastery-approach goal condition, whereas it was statistically significant in the performance-approach goal condition. These results suggest that mastery-approach goals eliminate retrieval-induced forgetting, but performance-approach goals do not, demonstrating that motivation factors can influence inhibition and forgetting

Thirst for knowledge: the effects of curiosity and interest on memory in younger and older adults

Given age-related memory impairments, one’s level of curiosity or interest could enhance memory for certain information. In the current study, younger and older adults read trivia questions, rated how curious they were to learn each answer, provided confidence and interest ratings, and judgments of learning (JOL) after learning the answer. No age-related differences in memory were found. Analyses indicated that curiosity and interest contributed to the formation of JOLs. Additionally, interest had a unique increasing relationship with older, but not younger, adults’ memory performance after a week. The results suggest that subjective interest may serve to enhance older adults’ memory

Factors Associated with Early Sexual Debut among Ghanaian Women from the Manya – Krobo District, – Ghana, 2011

Affiliation: Department of Epidemiology and Biostatistics GW, School of Public Health and Health Services Title: Factors associated with early sexual debut among Ghanaian women from the Manya – Krobo district, – Ghana, 2011 Background: The dipo, a Krobo puberty initiation rite practiced annually among an estimated 2,000 Ghanaian females ages 2–20, is a cultural rite of passage into womanhood that is intended to promote abstinence from sexual activity until marriage. Objectives: This study examined the risk of early sexual debut among dipo-initiated Krobo females versus uninitiated Krobo females. This study also assessed Manya–Krobo societal opinions regarding the sexual health outcomes of initiates and existing modifications of the rite. Methods: Mixed-methods. Utilizing a retrospective cohort study design, we surveyed 306 unwed Krobo females from Agormanya ages 13–20. We employed Cox proportional hazard regressions assessing the effects of model covariates upon sexual debut and age at sexual debut. Qualitative analysis included nine interviews conducted among Manya–Krobo district community members who either supported or opposed the dipo. Responses were analyzed using Dedoose QDA software to determine patterns in attitudes and opinions regarding initiates’ sexual behaviors and to identify current ceremonial changes. Results: Dipo initiated participants had a 1.8 increased hazard rate of early sexual debut as compared to uninitiated participants after adjusting for covariates, however, results were not statistically significant (aHR: 1.8, 95% C.I: 0.8–4.0). Qualitative data indicated that some dipo opponents stated participation promotes promiscuity and teen pregnancy while select supporters asserted the rite protects participants from these outcomes. Key ceremonial changes included a reduction in age eligibility and length of dipo preparatory period. Conclusions: These study findings do not offer conclusive evidence that participation in the dipo increases the risk of early sexual debut among initiated versus uninitiated Krobo females. Study findings suggest the reduction in age of dipo eligibility may increase the likelihood of sexual debut following the ceremony. Participants who received the rite as toddlers had a greater length of time between the dipo and adulthood to become sexually active post-initiation than females who were initiated during their late teens/early twenties