Supporting self-regulated learning in a blended learning environment using prompts and learning analytics

Higher education institutions, teachers, and students face new difficulties and opportunities resulting from the introduction of modern technology into the learning process. The widespread of learning environments that integrate online learning and face-to-face learning may pose some opportunities as well as difficulties for some groups of students' self-regulation skills. Providing automated prompts may help to support those students with insufficient self-regulation skills. The use of learning analytics and multiple methods and data sources (data triangulation) may give better insight into the self-regulation process. The objective of the proposed research is to explore the students' evaluation of the usefulness of prompts implemented in a blended learning environment. A secondary objective is to develop and evaluate a real-time dashboard designed to notify teachers of student responses to deployed prompts. The research methodology will be grounded in action research and empirical research. The scientific contribution will be achieved through the development of artefacts and the performance of empirical research to advance understanding of the student's self-regulation in a blended learning environment

Event-Related Potentials in Medical Workers with Long-Term Exposure to Xylene

The effects of chronic exposure to xylene on cognitive ability were studied in a group of 35 medical workers occupationally exposed to low-level concentrations of xylene for at least five years by using event-related potentials (ERPs), and compared with a control group of 21 subjects. The exposure to xylene was confirmed through determination of m-methylhippuric acid, a reliable biological indicator of xylene exposure, in pre- and post-shift urine. A dose-effect relationship between log m-methylhippuric acid and ERP log latency (p = 0.032), and the ERP amplitude (p = 0.047) was statistically significant. The group of medical workers showed significantly longer ERP log latency (p < 0.001) than did the control group with respect to factors of exposure to smoking, education and age as covariates. For the ERP amplitude the difference was found not to be significant (p = 0.263), probably due to high between subject variability. The cognitive impairment may occur in workers chronically exposed to xylene

Influence od storage duration on primary root and germ lenght of sunflower hybrid seed

Dorađeno sjeme (nezaprašeno) hibrida suncokreta Fakir, Orion i Apolon skladišteno je 36 mjeseci u dvoslojnim papir vrećama, u podnom betonskom skladištu s termoizolacijom (relativna vlaga zraka 55-60% i temperatura 10-12°C). Analiza istraživanih svojstava (dužina primarnog korijena i klice) bila je na početku skladištenja i nakon svakih 12 mjeseci skladištenja tijekom tri godine istraživanja. Rezultati istraživanja su pokazali da sjeme hibrida Fakir ima duži primarni korijen i klicu (0.3-0.6 cm i 0.3-0.7 cm) od Oriona i Apolona na početku i na kraju skladištenja. Hibrid Apolon ima najkraći primarni korijen i klicu (5.4 cm i 2.2 cm) na početku, kao i na kraju skladištenja (4.3 cm i 1.6 cm). Kod svih hibrida najveće smanjenje dužine primarnog korijena i klice bilo je poslije 36 mjeseca skladištenja. Dobivene razlike su statistički vrlo značajne za sva istraživana svojstva (hibrid, dužina skladištenja, interakcija hibrid x dužina skladištenja).After seed processing, sunflower seed Fakir, Orion and Apolon has been storage for 36 months. Seed samples were packed in two film paper bag and storage in two different storage. Concrete floor and storage with termoizolation (relative air humidity 55-60 % and air temperature 10 °C – 12 °C). In the time of storage, every 12 months, seed samples was getting and seed properties has been analyzed. After 36 months, primary root and germ length were measured. Results of this investigations approved, that Fakir hybrid seed has higher on primary root and germ length in accordance with Orion and Apolon. It was conclude that decreasing of primary root and germ length depend on hybrid and storage duration. Apolon hybrid had the largest decreasing of primary root (1.1cm) and germ length (0.6cm). Fakir hybrid had the smallest decreasing. Each hybrids in this investigations had the largest decreasing of primary root and germ length after 24 months of storage. Hybrid and storage duration, statistically very significant influence on seed quality decreasing

The fight for accretion: discovery of intermittent mass transfer in BB Doradus in the low state

Our long-term photometric monitoring of southern nova-like cataclysmic variables with the 1.3-m SMARTS telescope found BB Doradus fading from V ~ 14.3 towards a deep low state at V ~ 19.3 in April 2008. Here we present time-resolved optical spectroscopy of BB Dor in this faint state in 2009. The optical spectrum in quiescence is a composite of a hot white dwarf with Teff = 30000 +- 5000 K and a M3-4 secondary star with narrow emission lines (mainly of the Balmer series and HeI) superposed. We associate these narrow profiles with an origin on the donor star. Analysis of the radial velocity curve of the H-alpha emission from the donor star allowed the measurement of an orbital period of 0.154095 +- 0.000003 d (3.69828 +- 0.00007 h), different from all previous estimates. We detected episodic accretion events which veiled the spectra of both stars and radically changed the line profiles within a timescale of tens of minutes. This shows that accretion is not completely quenched in the low state. During these accretion episodes the line wings are stronger and their radial velocity curve is delayed by ~ 0.2 cycle, similar to that observed in SW Sex and AM Her stars in the high state, with respect to the motion of the white dwarf. Two scenarios are proposed to explain the extra emission: impact of the material on the outer edge of a cold, remnant accretion disc, or the combined action of a moderately magnetic white dwarf (B1 <~ 5 MG) and the magnetic activity of the donor star.Comment: 10 pages, 10 figures, accepted by MNRA

Wild Boar Tissue Levels of Cadmium, Lead and Mercury in Seven Regions of Continental Croatia

Concentrations of cadmium, mercury and lead were analysed by atomic absorption spectrometry in the kidney and muscle of free-living wild boar (n = 169) from hunting grounds in seven counties of continental Croatia. Mean levels of metals (mg/kg) in muscle and kidney of boars ranged as follows: Cd: 0.005–0.016 and 0.866–4.58, Pb: 0.033–0.15 and 0.036–0.441, Hg: 0.004–0.012 and 0.04–0.152. In all seven regions, concentrations exceeded the permitted values (muscle and kidney mg/kg: cadmium 0.05/1; lead 0.1/0.5; mercury 0.03/0.1) in 13.6% and 71.6% of samples (muscle and kidney, respectively) for cadmium; 13.6% and 8.9% for lead; 19.5% and 2.4% for mercury. There were significant differences among the regions. Vukovar-Srijem and Virovitica-Podravina Counties were highly contaminated with cadmium, Sisak-Moslavina and Virovitica-Podravina Counties with lead and Brod-Posavina County had highest mercury concentrations. These results suggest a detailed investigation of physiological and environmental factors contributing to accumulation of metals in boars

IP Pegasi: Investigation of the accretion disk structure. Searching evidences for spiral shocks in the quiescent accretion disk

We present the results of spectral investigations of the cataclysmic variable IP Peg in quiescence. Optical spectra obtained on the 6-m telescope at the Special Astrophysical Observatory (Russia), and on the 3.5-m telescope at the German-Spanish Astronomical Center (Calar Alto, Spain), have been analysed by means of Doppler tomography and Phase Modelling Technique. From this analysis we conclude that the quiescent accretion disk of IP Peg has a complex structure. There are also explicit indications of spiral shocks. The Doppler maps and the variations of the peak separation of the emission lines confirm this interpretation. We have detected that all the emission lines show a rather considerable asymmetry of their wings varying with time. The wing asymmetry shows quasi-periodic modulations with a period much shorter than the orbital one. This indicates the presence of an emission source in the binary rotating asynchronously with the binary system. We also have found that the brightness of the bright spot changes considerably during one orbital period. The spot becomes brightest at an inferior conjunction, whereas it is almost invisible when it is located on the distant half of the accretion disk. Probably, this phenomenon is due to an anisotropic radiation of the bright spot and an eclipse of the bright spot by the outer edge of the accretion disk.Comment: 13 pages, 11 figures (= 21 EPS files), accepted for publication in A&

Patient-specific Alzheimer-like pathology in trisomy 21 cerebral organoids reveals BACE2 as a gene dose-sensitive AD suppressor in human brain

A population of >6 million people worldwide at high risk of Alzheimer’s disease (AD) are those with Down Syndrome (DS, caused by trisomy 21 (T21)), 70% of whom develop dementia during lifetime, caused by an extra copy of β-amyloid-(Aβ)-precursor-protein gene. We report AD-like pathology in cerebral organoids grown in vitro from non-invasively sampled strands of hair from 71% of DS donors. The pathology consisted of extracellular diffuse and fibrillar Aβ deposits, hyperphosphorylated/pathologically conformed Tau, and premature neuronal loss. Presence/absence of AD-like pathology was donor-specific (reproducible between individual organoids/iPSC lines/experiments). Pathology could be triggered in pathology-negative T21 organoids by CRISPR/Cas9-mediated elimination of the third copy of chromosome-21-gene BACE2, but prevented by combined chemical β and γ-secretase inhibition. We found that T21-organoids secrete increased proportions of Aβ-preventing (Aβ1-19) and Aβ-degradation products (Aβ1-20 and Aβ1-34). We show these profiles mirror in cerebrospinal fluid of people with DS. We demonstrate that this protective mechanism is mediated by BACE2-trisomy and cross-inhibited by clinically trialled BACE1-inhibitors. Combined, our data prove the physiological role of BACE2 as a dose-sensitive AD-suppressor gene, potentially explaining the dementia delay in ~30% of people with DS. We also show that DS cerebral organoids could be explored as pre-morbid AD-risk population detector and a system for hypothesis-free drug screens as well as identification of natural suppressor genes for neurodegenerative diseases