Investigating the effect of auxiliary objectives for the automated grading of learner english speech transcriptions

We address the task of automatically grading the language proficiency of spontaneous speech based on textual features from automatic speech recognition transcripts. Motivated by recent advances in multi-task learning, we develop neural networks trained in a multi-task fashion that learn to predict the proficiency level of non-native English speakers by taking advantage of inductive transfer between the main task (grading) and auxiliary prediction tasks: morpho-syntactic labeling, language modeling, and native language identification (L1). We encode the transcriptions with both bi-directional recurrent neural networks and with bi-directional representations from transformers, compare against a feature-rich baseline, and analyse performance at different proficiency levels and with transcriptions of varying error rates. Our best performance comes from a transformer encoder with L1 prediction as an auxiliary task. We discuss areas for improvement and potential applications for text-only speech scoring.Cambridge Assessmen

Research Notes: Determinate-Dt2 Effects on Soybean Characteristics.

Bernard (1972) studied a gene, Dt2, which hastened the termination of apical stem growth and decreased both plant height and number of nodes per plant. In a \u27Harosoy\u27 background, a Dt2 isoline had a 15% reduction in height and was three days earlier maturing but was similar in yield to Harosoy . There was some reduction in weight per seed associated with the Dt2 effect

Mathematical modelling of tissue-engineering angiogenesis

We present a mathematical model for the vascularisation of a porous scaffold following implantation in vivo. The model is given as a set of coupled non-linear ordinary differential equations (ODEs) which describe the evolution in time of the amounts of the different tissue constituents inside the scaffold. Bifurcation analyses reveal how the extent of scaffold vascularisation changes as a function of the parameter values. For example, it is shown how the loss of seeded cells arising from slow infiltration of vascular tissue can be overcome using a prevascularisation strategy consisting of seeding the scaffold with vascular cells. Using certain assumptions it is shown how the system can be simplified to one which is partially tractable and for which some analysis is given. Limited comparison is also given of the model solutions with experimental data from the chick chorioallantoic membrane (CAM) assay

Skills embeddings: A neural approach to multicomponent representations of students and tasks

Educational systems use models of student skill to inform decision-making processes. Defining such a model manually is challenging due to the large number of relevant factors. We introduce an alternative approach by learning multidimensional representations (embeddings) from student activity data. Such embeddings are fixed-length real vectors with three desirable characteristics: co-location of similar students and items in a vector space; magnitude increases with skill, and that absence of a skill can be represented. Based on the Multicomponent Latent Trait Model, we use a neural network with complementary trainable weights to learn these embeddings by backpropagation in an unsupervised manner. We evaluate using synthetic student activity data that provides a ground-truth of student skills in order to understand the impact of number of students, question items and knowledge components in the domain. We find that our data-mined parameter values can recreate the synthetic datasets up to the accuracy of the model that generated them, for domains containing up to 10 simultaneously active knowledge components, which can be effectively mined using relatively small quantities of data (1000 students, 100 items). We describe a procedure to estimate the number of components in a domain, and propose a component-masking logic mechanism that improves performance on high-dimensional datasets.Cambridge Assessmen

Evidence for strong evolution of the cosmic star formation density at high redshift

Deep HST/ACS and VLT/ISAAC data of the GOODS-South field were used to look for high-redshift galaxies in the rest-frame UV wavelength range and to study the evolution of the cosmic star-formation density at z~7. The GOODS-South area was surveyed down to a limiting magnitude of about (J+Ks)=25.5 looking for drop-out objects in the z ACS filter. The large sampled area would allow for the detection of galaxies which are 20 times less numerous and 1-2 magnitudes brighter than similar studies using HST/NICMOS near-IR data. Two objects were initially selected as promising candidates of galaxies at z~7, but have subsequently been dismissed and identified as Galactic brown dwarfs through a detailed analysis of their morphology and Spitzer colors, as well as through spectroscopic information. As a consequence, we conclude that there are no galaxies at z~7 down to our limiting magnitude in the field we investigated. Our non detection of galaxies at z~7 provides clear evidence for a strong evolution of the luminosity function between z=6 and z=7, i.e. over a time interval of only ~170 Myr. Our constraints also provide evidence for a significant decline of the total star formation rate at z=7, which must be less than 40% of that at z=3 and 40-80% of that at z=6. We also derive an upper limit to the ionizing flux at z=7, which is only marginally consistent with that required to completely ionize the Universe.Comment: 11 pages, A&A, in press. New version after proof correctio

Accurate modelling of language learning tasks and students using representations of grammatical proficiency

Adaptive learning systems aim to learn the relationship between curriculum content and students in order to optimise a student’s learning process. One form of such a system is content recommendation in which the system attempts to predict the most suitable content to next present to the student. In order to develop such a system, we must learn reliable representations of the curriculum content and the student. We consider this in the context of foreign language learning and present a novel neural network architecture to learn such representations. We also show that by incorporating grammatical error distributions as a feature in our neural architecture, we can substantially improve the quality of our representations. Different types of grammatical error are automatically detected in essays submitted by students to an online learning platform. We evaluate our model and representations by predicting student scores and grammatical error distributions on unseen language tasks. We also discuss further uses for our model beyond content recommendation such as inferring student knowledge components for a given domain and optimising spacing and repetition of content for efficient long term retention.Cambridge Assessmen

Effect of tanniniferous browse meal on nematode faecal egg counts and internal parasite burdens in sheep and goats

The effect of tanniniferous browse meal on faecal egg counts (FEC) and intestinal worm burdens was investigated in sheep and goats infested experimentally with gastrointestinal nematodes. Initially, leaves of different browse tree species were assayed for condensed tannin (CT) content using a colorimetric method to determine concentration and seasonal variations. The level of CT in the leaves ranged between 58 – 283 g/kg dry matter. Seasonal changes in CT levels were influenced by stage of leaf maturity with peak levels after the wet season in June. Leaves of Acacia polyacantha had the highest tannin concentration and were used to test their anthelmintic effect in goats and sheep infested with the nematodes in two separate feeding trials. In Trial 1 an acacia leaf meal supplement (AMS) was offered at 100 – 130 g/animal/day for 20 days to growing Small East African goats to investigate its effect on FEC and worm burden. Mean FEC and worm burden of the AMS-fed group were respectively 27% and 13% lower than in the control group. Trial 2 was similar to Trial 1 except that AMS was offered for 30 days to growing Black Head Persian sheep at 170 g/animal/day. The sheep receiving AMS showed a slight reduction in FEC (on average 19% lower than the control group) but had no effect on worm burden. The current results substantiated previous reports of a suppressing effect of CT on gastrointestinal nematodes of small ruminants. Although the observed anthelmintic activity of AMS was less than expected, such reductions can have practical epidemiological implications in reducing pasture larval contamination. Further studies are needed under field conditions to evaluate the feasibility of using locally available tanniniferous browse as an alternative to synthetic anthelmintics in reducing worm infestations in small ruminants. South African Journal of Animal Science Vol. 37 (2) 2007: pp. 97-10

Prevalence and correlates of frailty among older adults: findings from the German health interview and examination survey

Background: Despite having the third highest proportion of people aged 60 years and older in the world, Germany has been recently reported as having the lowest prevalence of frailty of 15 European countries. The objective of the study is to describe the prevalence of frailty in a large nationwide population-based sample and examine associations with sociodemographic, social support and health characteristics. Methods: We performed a cross-sectional analysis of the first wave of the German Health Interview and Examination Survey for Adults (DEGS1) conducted 2008–2011. Participants were 1843 community-dwelling people aged 65–79 years. Frailty and pre-frailty were defined, according to modified Fried criteria, as 3 and more or 1–2 respectively, of the following: exhaustion, low weight, low physical activity, low walking speed and low grip strength. The Oslo-3 item Social Support Scale (OSS-3) was used. Patient Health Questionnaire (PHQ-9) measured depressive symptoms and the Digit Symbol Substitution Test (DSST) measured cognition. Associations between participants’ characteristics and frailty status were examined using unadjusted and adjusted multinomial logistic regression models estimating relative risk ratios (RRR) of frailty and pre-frailty. Results: The prevalence of frailty among women was 2.8% (CI 1.8-4.3) and pre-frailty 40.4% (CI 36.3-44.7) and among men was 2.3% (CI 1.3-4.1) and 36.9% (CI 32.7-41.3) respectively. Independent determinants of frailty, from unadjusted models, included older age, low socioeconomic status, poor social support, lower cognitive function and a history of falls. In adjusted models current depressive symptoms (RRR 12.86, CI 4.47-37.03), polypharmacy (RRR 7.78, CI 2.92-20.72) and poor hearing (RRR 5.38, CI 2.17-13.35) were statistically significantly associated with frailty. Conclusions: Frailty prevalence is relatively low among community-dwelling older adults in Germany. Modifiable characteristics like low physical activity provide relevant targets for individual and population-level frailty detection and intervention strategies

Declining Public Awareness of Heart Attack Warning Symptoms in the Years Following an Australian Public Awareness Campaign: A Cross-Sectional Study

Background: The National Heart Foundation of Australia's (NHFA) Warning Signs campaign ran between 2010 and 2013. This study examines trends in Australian adults’ ability to name heart attack symptoms during the campaign and in the years following. Methods: Using the NHFA's HeartWatch data (quarterly online surveys) for adults aged 30–59 years, we conducted an adjusted piecewise regression analysis comparing trends in the ability to name symptoms during the campaign period plus one year lag (2010–2014) to the post-campaign period (2015–2020) Results: Over the study period, there were 101,936 Australian adults surveyed. Symptom awareness was high or increased during the campaign period. However, there was a significant downward trend in each year following the campaign period for most symptoms (e.g., chest pain: adjusted odds ratio [AOR] =0.91, 95%CI: 0.56–0.80; arm pain: AOR=0.92, 95%CI: 0.90–0.94). Conversely, the inability to name any heart attack symptom increased in each year following the campaign (3.7% in 2010 to 19.9% in 2020; AOR=1.13, 95%CI: 1.10–1.15); these respondents were more likely to be younger, male, have less than 12 years of education, identify as Aboriginal and/or Torres Strait Islander Peoples, speak a language other than English at home and have no cardiovascular risk factors. Conclusion: Awareness of heart attack symptoms has decreased in the years since the Warning Signs campaign in Australia, with 1 in 5 adults currently unable to name a single heart attack symptom. New approaches are needed to promote and sustain this knowledge, and to ensure people act appropriately and promptly if symptoms occur

Gene and Cell-Based Therapies for Parkinson’s Disease: Where Are We?

Abstract: Parkinson’s disease (PD) is a neurodegenerative disorder that carries large health and socioeconomic burdens. Current therapies for PD are ultimately inadequate, both in terms of symptom control and in modification of disease progression. Deep brain stimulation and infusion therapies are the current mainstay for treatment of motor complications of advanced disease, but these have very significant drawbacks and offer no element of disease modification. In fact, there are currently no agents that are established to modify the course of the disease in clinical use for PD. Gene and cell therapies for PD are now being trialled in the clinic. These treatments are diverse and may have a range of niches in the management of PD. They hold great promise for improved treatment of symptoms as well as possibly slowing progression of the disease in the right patient group. Here, we review the current state of the art for these therapies and look to future strategies in this fast-moving field