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Developmental changes in the germinability, desiccation tolerance, hardseededness, and longevity of individual seeds of Trifolium ambiguum
Background and Aims: Using two parental clones of outcrossing Trifolium ambiguum as a potential model system, we examined how during seed development the maternal parent, number of seeds per pod, seed position within the pod, and pod position within the inflorescence influenced individual seed fresh weight, dry weight, water content, germinability, desiccation tolerance, hardseededness, and subsequent longevity of individual seeds.
Methods: Near simultaneous, manual reciprocal crosses were carried out between clonal lines for two experiments. Infructescences were harvested at intervals during seed development. Each individual seed was weighed and then used to determine dry weight or one of the physiological behaviour traits.
Key Results: Whilst population mass maturity was reached at 33–36 days after pollination (DAP), seed-to-seed variation in maximum seed dry weight, when it was achieved, and when maturation drying commenced, was considerable. Individual seeds acquired germinability between 14 and 44 DAP, desiccation tolerance between 30 and 40 DAP, and the capability to become hardseeded between 30 and 47 DAP. The time for viability to fall to 50 % (p50) at 60 % relative humidity and 45 °C increased between 36 and 56 DAP, when the seed coats of most individuals had become dark orange, but declined thereafter. Individual seed f. wt at harvest did not correlate with air-dry storage survival period. Analysing survival data for cohorts of seeds reduced the standard deviation of the normal distribution of seed deaths in time, but no sub-population showed complete uniformity of survival period.
Conclusions: Variation in individual seed behaviours within a developing population is inherent and inevitable. In this outbreeder, there is significant variation in seed longevity which appears dependent on embryo genotype with little effect of maternal genotype or architectural factors
The Science Behind Learning: Practical Applications of Curiosity, Sociality, and Emotion in Communication Center Consultations
How humans learn is a topic explored by many disciplines. Eyler (2018) synthesized research from diverse fields such as developmental psychology, anthropology, and cognitive neuroscience to identify themes important for understanding the science behind learning. Three of these principles have important relevance for center work: curiosity, sociality, and emotion. This paper explores practical strategies, based on these three principles, that consultants in communication centers can use to enhance learning and better assist students.Keywords: communication centers, consulting, science of learning, curiosity, sociality, emotio
Regional and foreign accent processing in English: can listeners adapt?
Recent data suggest that the first presentation of a foreign accent triggers a delay in word identification, followed by a subsequent adaptation. This study examines under what conditions the delay resumes to baseline level. The delay will be experimentally induced by the presentation of sentences spoken to listeners in a foreign or a regional accent as part of a lexical decision task for words placed at the end of sentences. Using a blocked design of accents presentation, Experiment 1 shows that accent changes cause a temporary perturbation in reaction times, followed by a smaller but long-lasting delay. Experiment 2 shows that the initial perturbation is dependent on participants' expectations about the task. Experiment 3 confirms that the subsequent long-lasting delay in word identification does not habituate after repeated exposure to the same accent. Results suggest that comprehensibility of accented speech, as measured by reaction times, does not benefit from accent exposure, contrary to intelligibility
The complexities of 'otherness': reflections on embodiment of a young White British woman engaged in cross-generation research involving older people in Indonesia
This article has been made available through the Brunel Open Access Publishing Fund.If interviews are to be considered embodied experiences, than the potential influence of the embodied researcher must be explored. A focus on specific attributes such as age or ethnicity belies the complex and negotiated space that both researcher and participant inhabit simultaneously. Drawing on empirical research with stroke survivors in an ethnically mixed area of Indonesia, this paper highlights the importance of considering embodiment as a specific methodological concern. Three specific interactions are described and analysed, illustrating the active nature of the embodied researcher in narrative production and development. The intersectionality of embodied features is evident, alongside their fluctuating influence in time and place. These interactions draw attention to the need to consider the researcher within the interview process and the subsequent analysis and presentation of narrative findings. The paper concludes with a reinforcement of the importance of ongoing and meaningful reflexivity in research, a need to consider the researcher as the other participant, and specifically a call to engage with and present the dynamic nature of embodiment
Metalinguistic Knowledge and Language Ability in University-Level L2 Learners
Existing research indicates that instructed learners' L2 proficiency and their metalinguistic knowledge are moderately correlated. However, the operationalization of the construct of metalinguistic knowledge has varied somewhat across studies. Metalinguistic knowledge has typically been operationalized as learners' ability to correct, describe, and explain L2 errors. More recently, this operationalization has been extended to additionally include learners' L1 language-analytic ability as measured by tests traditionally used to assess components of language learning aptitude. This article reports on a study which employed a narrowly focused measure of L2 proficiency and incorporated L2 language-analytic ability into a measure of metalinguistic knowledge. It was found that the linguistic and metalinguistic knowledge of advanced university-level L1 English learners of L2 German correlated strongly. Moreover, the outcome of a principal components analysis suggests that learners' ability to correct, describe, and explain highlighted L2 errors and their L2 language-analytic ability may constitute components of the same construct. The theoretical implications of these findings for the concept of metalinguistic knowledge in L2 learning are considered. © Oxford University Press 2007
An impact assessment methodology for urban surface runoff quality following best practice treatment
The paper develops an easy to apply desk-based semi-quantitative approach for the assessment of residual receiving water quality risks associated with urban surface runoff following its conveyance through best practice sustainable drainage systems (SUDS). The innovative procedure utilises an integrated geographical information system (GIS)-based pollution index approach based on surface area impermeability, runoff concentrations/loadings and individual SUDS treatment performance potential to evaluate the level of risk mitigation achievable by SUDS drainage infrastructure. The residual impact is assessed through comparison of the determined pollution index with regulatory receiving water quality standards and objectives. The methodology provides an original theoretically based procedure which complements the current acute risk assessment approaches being widely applied within pluvial flood risk management
Gamma ray burst distances and the timescape cosmology
Gamma ray bursts can potentially be used as distance indicators, providing
the possibility of extending the Hubble diagram to redshifts ~7. Here we follow
the analysis of Schaefer (2007), with the aim of distinguishing the timescape
cosmological model from the \LambdaCDM model by means of the additional
leverage provided by GRBs in the range 2 < z < 7. We find that the timescape
model fits the GRB sample slightly better than the \LambdaCDM model, but that
the systematic uncertainties are still too little understood to distinguish the
models.Comment: 7 pages, 7 figures, revised version accepted for publication in MNRA
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