20 research outputs found
Sex dependency of inhibitory control functions
BACKGROUND: Inhibition of irrelevant responses is an important aspect of cognitive control of a goal-directed behavior. Females and males show different levels of susceptibility to neuropsychological disorders such as impulsive behavior and addiction, which might be related to differences in inhibitory brain functions. METHODS: We examined the effects of ‘practice to inhibit’, as a model of rehabilitation approach, and ‘music’, as a salient contextual factor in influencing cognition, on the ability of females and males to perform a stop-signal task that required inhibition of initiated or planned responses. In go trials, the participants had to rapidly respond to a directional go cue within a limited time window. In stop trials, which were presented less frequently, a stop signal appeared immediately after the go-direction cue and the participants had to stop their responses. RESULTS: We found a significant difference between females and males in benefiting from practice in the stop-signal task: the percentage of correct responses in the go trials increased, and the ability to inhibit responses significantly improved, after practice in females. While listening to music, females became faster but males became slower in responding to the go trials. Both females and males became slower in performing the go trials following an error in the stop trials; however, music significantly affected this post-error slowing depending on the sex. Listening to music decreased post-error slowing in females but had an opposite effect in males. CONCLUSIONC: Here, we show a significant difference in executive control functions and their modulation by contextual factors between females and males that might have implications for the differences in their propensity for particular neuropsychological disorders and related rehabilitation approaches
Sediment source fingerprinting: benchmarking recent outputs, remaining challenges and emerging themes
Abstract: Purpose: This review of sediment source fingerprinting assesses the current state-of-the-art, remaining challenges and emerging themes. It combines inputs from international scientists either with track records in the approach or with expertise relevant to progressing the science. Methods: Web of Science and Google Scholar were used to review published papers spanning the period 2013–2019, inclusive, to confirm publication trends in quantities of papers by study area country and the types of tracers used. The most recent (2018–2019, inclusive) papers were also benchmarked using a methodological decision-tree published in 2017. Scope: Areas requiring further research and international consensus on methodological detail are reviewed, and these comprise spatial variability in tracers and corresponding sampling implications for end-members, temporal variability in tracers and sampling implications for end-members and target sediment, tracer conservation and knowledge-based pre-selection, the physico-chemical basis for source discrimination and dissemination of fingerprinting results to stakeholders. Emerging themes are also discussed: novel tracers, concentration-dependence for biomarkers, combining sediment fingerprinting and age-dating, applications to sediment-bound pollutants, incorporation of supportive spatial information to augment discrimination and modelling, aeolian sediment source fingerprinting, integration with process-based models and development of open-access software tools for data processing. Conclusions: The popularity of sediment source fingerprinting continues on an upward trend globally, but with this growth comes issues surrounding lack of standardisation and procedural diversity. Nonetheless, the last 2 years have also evidenced growing uptake of critical requirements for robust applications and this review is intended to signpost investigators, both old and new, towards these benchmarks and remaining research challenges for, and emerging options for different applications of, the fingerprinting approach
A deconvolutional Bayesian mixing model approach for river basin sediment source apportionment
Increasing complexity in human-environment interactions at multiple watershed scales presents major challenges to sediment source apportionment data acquisition and analysis. Herein, we present a step-change in the application of Bayesian mixing models: Deconvolutional-MixSIAR (D-MIXSIAR) to underpin sustainable management of soil and sediment. This new mixing model approach allows users to directly account for the 'structural hierarchy' of a river basin in terms of sub-watershed distribution. It works by deconvoluting apportionment data derived for multiple nodes along the stream-river network where sources are stratified by sub-watershed. Source and mixture samples were collected from two watersheds that represented (i) a longitudinal mixed agricultural watershed in the south west of England which had a distinct upper and lower zone related to topography and (ii) a distributed mixed agricultural and forested watershed in the mid-hills of Nepal with two distinct sub-watersheds. In the former, geochemical fingerprints were based upon weathering profiles and anthropogenic soil amendments. In the latter compound-specific stable isotope markers based on soil vegetation cover were applied. Mixing model posterior distributions of proportional sediment source contributions differed when sources were pooled across the watersheds (pooled-MixSIAR) compared to those where source terms were stratified by sub-watershed and the outputs deconvoluted (D-MixSIAR). In the first example, the stratified source data and the deconvolutional approach provided greater distinction between pasture and cultivated topsoil source signatures resulting in a different posterior distribution to non-deconvolutional model (conventional approaches over-estimated the contribution of cultivated land to downstream sediment by 2 to 5 times). In the second example, the deconvolutional model elucidated a large input of sediment delivered from a small tributary resulting in differences in the reported contribution of a discrete mixed forest source. Overall D-MixSIAR model posterior distributions had lower (by ca 25-50%) uncertainty and quicker model run times. In both cases, the structured, deconvoluted output cohered more closely with field observations and local knowledge underpinning the need for closer attention to hierarchy in source and mixture terms in river basin source apportionment. Soil erosion and siltation challenge the energy-food-water-environment nexus. This new tool for source apportionment offers wider application across complex environmental systems affected by natural and human-induced change and the lessons learned are relevant to source apportionment applications in other disciplines
Internet use and its addiction level in medical students
Namrata Upadhayay,1 Sanjeev Guragain2 1Department of Physiology; 2Department of Pharmacology, Gandaki Medical College, Pokhara Lekhnath, Nepal Objective: To compare the Internet addiction levels between male and female medical students.Methods: One hundred medical students (male: 50, female: 50) aged 17–30 years were included in a cross-sectional study. A standardized questionnaire was used to assess their Internet addiction level. Additionally, a self-designed questionnaire was used to identify the various purposes of Internet use among the students. The Internet addiction score (based on the Internet Addiction Test) was compared between male and female students by using the Mann–Whitney U test (p≤0.05). After knowing their addiction level, we interviewed students to know if Internet use had any bad/good impact on their life. Results: The Internet Addiction Test scores obtained by the students were in the range of 11–70. Out of 100 students, 21 (male: 13, female: 8) were found to be slightly addicted to the Internet. The remaining 79 students were average online users. There was no significant difference between male and female students in the addiction level (score). However, males were more addicted than females. The major use of Internet was to download and watch movies and songs and to communicate with friends and family (76/100). Some students (24/100) used the Internet to assess information that helped them in their educational and learning activities. Some students mentioned that overuse of the Internet lead to insufficient amounts of sleep and affected their concentration levels in the classroom during lectures.Conclusion: Medical students are experiencing problems due to Internet overuse. They experience poor academic progress and lack of concentration while studying. The main use of the Internet was for entertainment and to communicate with friends and family. Keywords: addiction, Internet, medical students, entertainmen
Effect of NPK Application at Two Levels on Yield and Yield Component of Rainfed Shallow Lowland Rice
A Field experiment was carried out at Crop Research Station, (ANDUAT), Ghaghraghat, Bahraich to evaluate the effect of two levels of fertilizers (F1: 60-30-20 & F2: 120-60-40 NPK kg/ha) on grain yield of Seven Advance Varietal Trial-2 rice cultures (IET 29026, IET 27538, IET 29031, IET 29032, IET 26744, IET 28281 and IET 27547) under rainfed shallow land in split plot design with three replications. Soil of the experimental field was sandy loam with pH 7.2, organic carbon 0.40%, Nitrogen 200 kg/ha, P2O5 24 kg/ha and K2O 234 kg/ha. Results revealed that application of higher level of fertilizers significantly increased the grain yield of rice cultures. IET 26744 recorded maximum grain yield (5.25 t/ha) followed by IET 29032 (5.20 t/ha) at higher dose of fertilizers and per cent increase over lower dose were 55.78 and 67.20, respectively. At 50% recommended dose of fertilizers variety Swarna-Sub 1 yielded maximum grain (3.54 t/ha) followed by IET 26744 (3.37 t/ha). All cultivars yielded higher at 100 per cent recommended dose of fertilizers
In vitro degradation of fluoranthene by bacteria isolated from petroleum sludge
An investigation was carried out for in vitro degradation of fluoranthene by four bacterial strains (PSM6, PSM7, PSM10 and PSM11) isolated from the petroleum sludge. Although all the strains registered their growth in MSM with 100 ppm fluoranthene, PSM11 growth was better than other strains. Growth of bacterial strains invariably corresponded to their degradation potential of fluoranthene. After 168 h of incubation, 61% fluoranthene was degraded by PSM11, followed by PSM10 (48%) and PSM6 (42%) and the least was recorded in PSM7 (41%). Besides, 11% loss in fluoranthene was attributed to abiotic factors. Thirty-eight times more activity of catechol 2,3-dioxygenase than catechol 1,2-dioxygenase showed that it played a significant role in fluoranthene degradation. Molecular weight of catechol 2,3-dioxygenase isolated from PSM11 was determined as not, vert, ~136 kDa by size exclusion chromatography and 34 kDa on denaturing SDS-PAGE, indicating tetrameric nature of the enzyme