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How and why do Educational Psychology Services engage with an ACE-informed approach?
No full textAdverse childhood experiences (ACEs) and related approaches are receiving increasing focus from education policy makers and educational psychologists. However, the extent to which ACEs research and theory can be used to inform practice continues to be a topic for debate. The present paper explores the development of ACE-informed practice within two UK local authority educational psychology services, through use of focus groups and interviews with educational psychologists. Rationale, facilitators and barriers to the development of current ACE-informed practice are reported. Implications for educational psychology practice, including consideration of risk and reliance factors, the importance of consistent implementation of approaches, and future research are also considered
Density functional theory study into the reaction mechanism of isonitrile biosynthesis by the nonheme iron enzyme ScoE
No full textThe nonheme iron enzyme ScoE catalyzes the biosynthesis of an isonitrile substituent in a peptide chain. To understand details of the reaction mechanism we created a large active site cluster model of 212 atoms that contains substrate, the active oxidant and the first- and second-coordination sphere protein and solvent. Several possible reaction mechanisms were tested and it is shown that isonitrile can only be formed through two consecutive catalytic cycles that both use one molecule of dioxygen and -ketoglutarate. In both cycles the active species is an iron(IV)-oxo species that in the first reaction cycle reacts through two consecutive hydrogen atom abstraction steps: first from the N-H group and thereafter from the C-H group to desaturate the N=C bond. The alternative ordering of hydrogen atom abstraction steps was also tested but found to be higher in energy. Moreover, the electronic configurations along that pathway implicate an initial hydride transfer followed by proton transfer. We highlight an active site Lys residue that is shown to donate charge interactions in the transition states and influence the relative barrier heights and bifurcation pathways. A second catalytic cycle of the reaction of iron(IV)-oxo with desaturated substrate starts with hydrogen atom abstraction followed by decarboxylation to give isonitrile directly. The latter will require a proton transfer to iron(II)-hydroxo to generate iron(II)-water and close the catalytic cycle. The work is compared with experimental observation and previous computational studies on this system and put in a larger perspective of nonheme iron chemistry
Comparison of continuous sampling with active noise cancellation and sparse sampling for cortical and subcortical auditory fMRI
No full textPurpose: Detecting sound-related activity using fMRI requires the auditory stimulus to be more salient than the intense background scanner acoustic noise. Various strategies can reduce the impact of scanner acoustic noise including “sparse” temporal sampling with single/clustered acquisitions providing intervals without any background scanner acoustic noise, or active noise cancellation (ANC) during “continuous” temporal sampling which generates an acoustic signal that adds destructively to the scanner acoustic noise substantially reducing the acoustic energy at the participant’s eardrum. Further, multiband fMRI allows multiple slices to be collected simultaneously, thereby reducing scanner acoustic noise in a given sampling period. Methods: 1.5mm isotropic multiband fMRI with sparse sampling (effective TR 9,000ms, acquisition duration 1,962ms) and continuous sampling (TR 2,000ms) with ANC were compared in 15 normally hearing participants. A sustained broadband noise stimulus was presented to drive activation of both sustained and transient auditory responses within subcortical and cortical auditory regions Results: Robust broadband noise-related activity was detected throughout the auditory pathways. Continuous sampling with ANC was found to give a statistically significant advantage over sparse sampling for the detection of the transient (onset) stimulus responses particularly in auditory cortex (p<0.001) and inferior colliculus (p<0.001), whereas gains provided by sparse over continuous ANC for detecting offset and sustained responses were marginal (p~0.05 in superior olivary complex, inferior colliculus, medial geniculate body, and auditory cortex). Conclusions: Sparse and continuous ANC multiband fMRI protocols provide differing advantages for observing the transient (onset and offset) and sustained stimulus responses
Exploring the impacts of the inequality of water permit allocation and farmers’ behaviors on the performance of an agricultural water market
No full textWater markets are considered as effective mechanisms to support efficient use of limited water resources and to increase crop production in agricultural systems. This study presents an agent-based modeling (ABM) framework to explore the performance of an agricultural water market under the joint influence of water permit allocation and farmers’ behaviors. The ABM employs a power law function to simulate water permit distribution among farmers for any given level of inequality measured by the Gini coefficient. Farmers’ irrigation behavior (i.e., sensitivity to soil dryness) and bidding behaviors (i.e., degree of rent seeking and learning rate coefficient) are explicitly incorporated into the ABM to represent farmers’ decision-making in a water market based on double auction. Through a set of scenario analyses in a study area in Texas, we find that the water market performance to increase basin-level crop production is constrained by a joint effect of, especially the complex and non-linear interplay between the inequality of water permit allocation, farmers’ behaviors, and hydrological conditions. The potential market performance is higher when water permits are more unequally distributed. The relative market performance is higher when the inequality of water allocation is at a moderate level. The modeling results can advance our understanding of the key contributing factors in market transactions, and provide policy implications to assess the comparative advantage between institutional development and farmers’ behavioral change for improving market performance. This study also provides model implications for future research to draw more robust conclusions about market benefits in the real world
Thermal ageing of a commercial LNT catalyst: effects on the structure and functionalities.
No full textHydrothermal degreening and ageing procedures were applied to a tri-metal (Pt-Pd-Rh) fully formulated lean NOX Trap catalyst to evaluate the effects of thermal stress on the performances and structural properties. X-ray absorption fine structure (XAFS) analysis revealed that the average size of the platinum particles was the same after degreening and ageing treatments. The formation of a new phase of alloyed Pt-Pd was observed to increase with the thermal load. The size of the ceria particles also increased after the ageing treatment. NOX storage capacity experiments revealed a substantial decrease of the concentration of active NOX storage sites which correlated with both ageing and degreening protocols. The performances of the treated catalyst were evaluated through spatially resolved (SpaciMS) lean-rich cycles. During the lean phase, the impact of the decrease in storage sites was significant on the aged sample, where an enlargement of the area required to achieve full storage was observed. On the other hand, the regeneration functionalities did not appear to be particularly affected by ageing. Rather, the aged sample showed a decrease of oxygen storage capacity (OSC), which promoted a lower reductant consumption and therefore a quicker and more efficient reduction process. On the other hand, the different distributions of adsorbed species by the end of the lean phase produced greater spread presence of NH3 and NOX slip along the channels of the aged sample during the reduction
Sputtered Oxide Thin-Film Transistors with Tunable Synaptic Spiking Behavior at One Volt
No full textIndium-gallium-zinc-oxide (IGZO) thin-film transistors (TFTs) gated with sputtered silicon dioxide dielectric were fabricated. Under different sputtering pressure of the silicon dioxide, the device is able to produce transfer curves from clockwise hysteresis to anti-clockwise hysteresis, corresponding to different operation modes and thus adding complementary performance by the same material system and device structure. In the interface-trapping mode, the transistor exhibited inhibitory synaptic spiking behavior induced by positive stimuli. In the electric-double-layer coupling mode, positive stimuli led to excitatory synaptic spiking behavior while negative stimuli resulted in inhibitory synaptic spiking behavior. All the transistor and synaptic spiking behaviours are conducted within ±1 V range. Enriched functionality and ultra-low operation voltage makes sputtered SiO2 gated IGZO TFTs promising candidate for neuromorphic applications
Genetic, immunological, and clinical features of 32 patients with autosomal recessive STAT1 deficiency
No full textAutosomal recessive (AR) STAT1 deficiency is a severe inborn error of immunity disrupting cellular responses to type I, II, and III IFNs, and IL-27, conferring a predisposition to both viral and mycobacterial infections. We report the genetic, immunological, and clinical features of an international cohort of 32 patients from 20 kindreds: 24 patients with complete deficiency and eight patients with partial deficiency. Twenty-four patients suffered from mycobacterial disease (BCG =13, environmental mycobacteria =10, or both in one patient). Fifty-four severe viral episodes occurred in 16 patients, mainly caused by Herpesviridae viruses. Attenuated live MMR and/or VZV vaccines triggered severe reactions in the five patients with complete deficiency. Seven patients developed features of hemophagocytic syndrome. Twenty-one patients died, and death was almost twice as likely in patients with complete STAT1 deficiency than in those with partial STAT1 deficiency. All but one of the eight survivors with AR complete deficiency underwent hematopoietic stem cell transplantation (HSCT). Overall survival after HSCT was 64%. A diagnosis of AR STAT1 deficiency should be considered in children with mycobacterial and/or viral infectious diseases. It is important to distinguish between complete and partial forms of AR STAT1 deficiency, as their clinical outcome and management differ significantly
Experimental and numerical investigation on post earthquake fire behaviour of the circular concrete filled steel tube columns
No full textPost earthquake fire is a common disaster which cause s serious safety issues to infrastructures . This study aims to investigate the residual loading capacities of circular concrete filled steel tube (CFST) columns under post earthquake fire experimentally and numerically. The experimental programme contains two loading steps pre damage cyclic loading at room temperature and transient state tests with constant compression loads. Three finite element models are developed and validated against the test results. Upon validation, a total of 48 numerical results were generated in the parametric study to investigate the effects of thickness and strengths of steel tube, axial compression ratio and damage degree on the fire resistance of circular CFST columns. Based on the analysis on experimental and numerical results, the loading mechanism of circular CFST columns is discussed. A design method is proposed for the prediction of fire resistance time under different seismic pre damage and compression loads. The predictions by the new method is compared with the newly generated experimental and numerical results and is found to be accurate and consistent with the mean value close to the unity and a coefficient of variation around 1
Novel eco-efficient reactive distillation process for dimethyl carbonate production by indirect alcoholysis of urea
No full textDimethyl carbonate is an eco-friendly essential chemical that can be sustainably produced from CO2, which is available from carbon capture activities or can even be captured from the air. The rapid increase in dimethyl carbonate demand is driven by the fast growth of polycarbonates, solvent, pharmaceutical, and lithium-ion battery industries. Dimethyl carbonate can be produced from CO2 through various chemical pathways, but the most convenient route reported is the indirect alcoholysis of urea. Previous research used techniques such as heat integration and reactive distillation to reduce the energy use and costs, but the use of an excess of methanol in the trans-esterification step led to an energy intensive extractive distillation required to break the dimethyl carbonate – methanol azeotrope. This work shows that the production of dimethyl carbonate by indirect alcoholysis of urea can be improved by using an excess of propylene carbonate (instead of an excess of methanol) – a neat feat that we showed it requires only 2.64 kWh/kg dimethyl carbonate in a reaction-separation-recycle process – and a reactive distillation column that effectively replaces two conventional distillation columns and the reactor for dimethyl carbonate synthesis. Therefore, less equipment is required, the methanol - dimethyl carbonate azeotrope does not need to be recycled, and the overall savings are higher. Moreover, we propose the use of a reactive distillation column in a heat integrated process to obtain high purity dimethyl carbonate (>99.8% wt.). The energy requirement is reduced by heat integration to just 1.25 kWh/kg dimethyl carbonate, which is about 52% lower than the reaction-separation-recycle process. To benefit from the energy savings, the dynamics and control of the process are provided for ±10% changes in the nominal rate of 32 ktpy dimethyl carbonate, and for uncertainties in reaction kinetics