QRTEngine: An easy solution for running online reaction time experiments using Qualtrics

Performing online behavioral research is gaining increased popularity among researchers in psychological and cognitive science. However, the currently available methods for conducting online reaction time experiments are often complicated and typically require advanced technical skills. In this article, we introduce the Qualtrics Reaction Time Engine (QRTEngine), an open-source JavaScript engine that can be embedded in the online survey development environment Qualtrics. The QRTEngine can be used to easily develop browser-based online reaction time experiments with accurate timing within current browser capabilities, and it requires only minimal programming skills. After introducing the QRTEngine, we briefly discuss how to create and distribute a Stroop task. Next, we describe a study in which we investigated the timing accuracy of the engine under different processor loads using external chronometry. Finally, we show that the QRTEngine can be used to reproduce classic behavioral effects in three reaction time paradigms: a Stroop task, an attentional blink task, and a masked-priming task. These findings demonstrate that QRTEngine can be used as a tool for conducting online behavioral research even when this requires accurate stimulus presentation times

Морфологические изменения в нижнеальвеолярном нерве на экспериментальной модели его травмы разной степени тяжести

У роботі на 40 лабораторних щурах досліджено закономірності та патоморфологічні зміни у нижньоальвеолярному нерві й параневральных тканинах у різний термін після операції, що викликані різним ступенем дії травмуючого фактору.During the experiments on 40 laboratory rodents we have studied the regularities and pathomorphological changes in lower dental nerve and paraneural tissues induced by disturbing factor of varying influence intensity observed at different postoperative periods

Histopathological changes in the reproductive system (ovaries and testes) of Oreochromis mossambicus following exposure to DDT

A b s t r a c t This study assesses the effects of 1,1-bis (4-chlorophenyl)-2,2,2-trichloroethane (DDT) on the reproduction and gonadal histology of adult Mozambique tipalia (Oreochromis mossambicus). The fish were allowed to breed, following exposure to 2 and 5 jig/l of waterborne technical-grade DDT for 40 days. Fertilized eggs were artificially incubated. In the 5 jig/l exposure, posthatch survival was significantly lower, and prevalence of larval skeletal deformities significantly higher, compared to the control (p<0.05). Incomplete axial development was the common gross deformity in posthatch larvae, caused by failure to develop chondroblasts posterior to the buccopharyngeal cavity. There were no significant differences in the gonadosomatic index of exposed and non-exposed male and female adults. The exposure caused increased oocyte atresia in the ovaries and disorganization of seminiferous lobules in the testes of adults. DDT exposure reduced survival and increased deformities in larvae, at levels that did not cause severe histopathological changes to parental gonads

Auditory presentation and synchronization in Adobe Flash and HTML5/JavaScript Web experiments

Substantial recent research has examined the accuracy of presentation durations and response time measurements for visually presented stimuli in Web-based experiments, with a general conclusion that accuracy is acceptable for most kinds of experiments. However, many areas of behavioral research use auditory stimuli instead of, or in addition to, visual stimuli. Much less is known about auditory accuracy using standard Web-based testing procedures. We used a millisecond-accurate Black Box Toolkit to measure the actual durations of auditory stimuli and the synchronization of auditory and visual presentation onsets. We examined the distribution of timings for 100 presentations of auditory and visual stimuli across two computers with difference specs, three commonly used browsers, and code written in either Adobe Flash or JavaScript. We also examined different coding options for attempting to synchronize the auditory and visual onsets. Overall, we found that auditory durations were very consistent, but that the lags between visual and auditory onsets varied substantially across browsers and computer systems

Compression of morbidity in a progeroid mouse model through the attenuation of myostatin/activin signalling

Background One of the principles underpinning our understanding of ageing is that DNA damage induces a stress response that shifts cellular resources from growth towards maintenance. A contrasting and seemingly irreconcilable view is that prompting growth of, for example, skeletal muscle confers systemic benefit. Methods To investigate the robustness of these axioms, we induced muscle growth in a murine progeroid model through the use of activin receptor IIB ligand trap that dampens myostatin/activin signalling. Progeric mice were then investigated for neurological and muscle function as well as cellular profiling of the muscle, kidney, liver, and bone. Results We show that muscle of Ercc1(Delta/-) progeroid mice undergoes severe wasting (decreases in hind limb muscle mass of 40-60% compared with normal mass), which is largely protected by attenuating myostatin/activin signalling using soluble activin receptor type IIB (sActRIIB) (increase of 30-62% compared with untreated progeric). sActRIIB-treated progeroid mice maintained muscle activity (distance travel per hour: 5.6 m in untreated mice vs. 13.7 m in treated) and increased specific force (19.3 mN/mg in untreated vs. 24.0 mN/mg in treated). sActRIIb treatment of progeroid mice also improved satellite cell function especially their ability to proliferate on their native substrate (2.5 cells per fibre in untreated progeroids vs. 5.4 in sActRIIB-treated progeroids after 72 h in culture). Besides direct protective effects on muscle, we show systemic improvements to other organs including the structure and function of the kidneys; there was a major decrease in the protein content in urine (albumin/creatinine of 4.9 sActRIIB treated vs. 15.7 in untreated), which is likely to be a result in the normalization of podocyte foot processes, which constitute the filtration apparatus (glomerular basement membrane thickness reduced from 224 to 177 nm following sActRIIB treatment). Treatment of the progeric mice with the activin ligand trap protected against the development of liver abnormalities including polyploidy (18.3% untreated vs. 8.1% treated) and osteoporosis (trabecular bone volume; 0.30 mm(3) in treated progeroid mice vs. 0.14 mm(3) in untreated mice, cortical bone volume; 0.30 mm(3) in treated progeroid mice vs. 0.22 mm(3) in untreated mice). The onset of neurological abnormalities was delayed (by similar to 5 weeks) and their severity reduced, overall sustaining health without affecting lifespan. Conclusions This study questions the notion that tissue growth and maintaining tissue function during ageing are incompatible mechanisms. It highlights the need for future investigations to assess the potential of therapies based on myostatin/activin blockade to compress morbidity and promote healthy ageing.Peer reviewe

Transmural collaborative care model for the review of antipsychotics: a feasibility study of a complex intervention

General practitioners (GPs) are often unaware of antipsychotic (AP)-induced cardiovascular risk (CVR) and therefore patients using atypical APs are not systematically monitored. We evaluated the feasibility of a complex intervention designed to review the use of APs and advise on CVR-lowering strategies in a transmural collaboration. A mixed methods prospective cohort study in three general practices in the Netherlands was conducted in 2021. The intervention comprised three steps: a digital information meeting, a multidisciplinary meeting, and a shared decision-making visit to the GP. We assessed patient recruitment and retention rates, advice given and adopted, and CVR with QRISK3 score and mental state with MHI-5 at baseline and three months post-intervention. GPs invited 57 of 146 eligible patients (39%), of whom 28 (19%) participated. The intervention was completed by 23 (82%) and follow-up by 18 participants (64%). At the multidisciplinary meeting, 22 (78%) patients were advised to change AP use. Other advice concerned medication (other than APs), lifestyle, monitoring, and psychotherapy. At 3-months post-intervention, 41% (28/68) of this advice was adopted. Our findings suggest that this complex intervention is feasible for evaluating health improvement in patients using AP in a trial