Reinforced Research Articles

Modelling, Simulation and Testing of Steer-by-Wire System with Variable Steering Ratio Control Strategy in 14-DOF Full Vehicle Model

This research explores the application of Proportional-Integral-Derivative (PID) controllers and Variable Steering Ratio (VSR) control strategies within a Steer-by-Wire (SbW) system, utilizing a comprehensive 14 Degrees of Freedom (DOF) full vehicle dynamic model. The study aims to advance vehicle dynamics and control through SbW technology. This research addresses the challenge of optimizing steering control by integrating an SbW system with PID and VSR strategies to overcome the limitations of traditional steering mechanisms and enhance vehicle responsiveness and stability. The SbW system, using a PID-based controller, was rigorously tested and validated using MATLAB Simulink and Hardware-in-the-Loop System (HiLS) method. The performance of the system was assessed through four distinct signal tests: step, sine, square, and sawtooth inputs. These tests confirmed the precision of the PID controller in position tracking. To improve the practical applicability of the SbW system, a 14-DOF vehicle dynamic model was developed and validated before integration with the SbW system. The integrated system accurately replicated conventional steering behavior, as validated by Step Steer Input (SSI) and Double Lane Change (DLC) tests, demonstrating less than 11% RMS percentage error - well within the acceptable threshold of less than 15%. Additionally, the study proposed and validated VSR control strategies through the DLC test. Results indicate that the PID controller effectively tracked desired signals, while the VSR strategy reduced driver workload and improved steering stability. This research offers valuable insights into enhancing SbW system performance and lays a foundation for future advancements in vehicle control systems.

Choice versus no choice: Practical considerations for increasing choices.

Choice involves engaging in a selection response when multiple options are concurrently available. Choices can be incorporated into many components of behavior-analytic treatment such as providing clients with a choice between multiple items, activities, or tasks. We reviewed the main characteristics of 38 behavior-analytic articles that compared choice and no-choice conditions. We coded the experimental arrangements of choice and no-choice conditions and analyzed potential factors affecting preferences for choice and no choice. The findings suggest that the sizing of alternatives from which to choose, the timing of choice opportunities, and the timing of the delivery of the chosen option varied across the studies. Furthermore, preferences for choice shifted with differential reinforcement history and response effort manipulations of choice or no choice. The findings suggest that individual variables should be considered when providing choices, but more research is needed.

BIOM-25. MOLECULAR PROFILING PREDICTS EARLY AND LATE PROGRESSION IN GLIOBLASTOMA

Abstract Patients with glioblastoma experience a wide variation in response to standard treatment, with nearly 30% experiencing tumour progression during treatment, and nearly 6% surviving more than 5 years. To date, there are few non-invasive clinical biomarkers to predict response to first – line treatment. Chemical exchange saturation transfer (CEST) MRI may have the potential to fill this gap. CEST MRI is sensitive to treatment-induced changes and changes in tumor metabolism. Our team has obtained CEST data for patients before, during and after the end of standard chemoradiation treatment, and found that CEST provides markers of early response and can identify early, standard and late progressors before treatment initiation. In this study, we aimed to establish molecular profiles of early, standard and late progressors with IDH wild-type glioblastoma. Patients (n=180) with primary, IDH wild-type glioblastoma were imaged with CEST-MRI at multiple time points throughout standard chemoradiation treatment. DNA and RNA were co-extracted from matched normal and tumour pairs and processed for whole genome sequencing, enzymatic methyl-seq and gene expression analysis using Nanostring. Clinical variables such as age, extent of resection, sex, ECOG status and MGMT promoter methylated were also collected. A survival analysis was conducted using the Kaplan-Meier method with log-rank tests. Univariate and multi-variate hazard ratios for clinical variables were calculated by fitting Cox Proportional Hazards Models. Early progressors reported a median progression-free survival (PFS) of 142 days compared to 832 days in late progressors (p<0.0001). Early progressors also harbored distinct and statistically significant differences in gene expression and genomic alterations, namely in DNA damage repair, glucose transport and arginine metabolism pathways. A gene signature was prognostic of PFS and overall survival. Collectively, this data has the potential to serve as a radiogenomic biomarker to assess treatment response before or within early phases of treatment and allow for individual tailoring of the treatment plan.

Advancing composite 3D printing: deep learning-optimized rheology-modified polymers with continuous carbon fiber reinforcement

Advancing composite 3D printing: deep learning-optimized rheology-modified polymers with continuous carbon fiber reinforcement

New Rotating Coanda-Type Intake for Sediment-Laden Flows

Tyrolean and Coanda types of water intake structures are the most widely preferred bottom intake structures used to divert water from channels and river systems for various purposes, such as energy production, irrigation, and domestic use. Estimation of withdrawal water and filtered sediment amounts are important to obtain maximum efficiency from an intake structure. The purpose of this study is to numerically analyze a newly patented rotating Coanda-type intake system to achieve the highest Water Capturing Efficiency and Sediment Release Efficiency. The newly patented system (patent no: TR2021011306B) presented here incorporates Coanda screens with variable void ratios, autonomously selected based on the sediment characteristics of the inflowing water. The process of selecting and positioning the appropriate screen is fully automated, requiring no human intervention. The system rotates under motor control to place the suitable screen at the operational point based on the specific requirements of the incoming sediment-laden flow.

Single-cell multiomics analysis of chronic myeloid leukemia links cellular heterogeneity to therapy response.

The advent of tyrosine kinase inhibitors (TKIs) as treatment of chronic myeloid leukemia (CML) is a paradigm in molecularly targeted cancer therapy. Nonetheless, TKI-insensitive leukemia stem cells (LSCs) persist in most patients even after years of treatment and are imperative for disease progression as well as recurrence during treatment-free remission (TFR). Here, we have generated high-resolution single-cell multiomics maps from CML patients at diagnosis, retrospectively stratified by BCR::ABL1IS (%) following 12 months of TKI therapy. Simultaneous measurement of global gene expression profiles together with >40 surface markers from the same cells revealed that each patient harbored a unique composition of stem and progenitor cells at diagnosis. The patients with treatment failure after 12 months of therapy had a markedly higher abundance of molecularly defined primitive cells at diagnosis compared to the optimal responders. The multiomic feature landscape enabled visualization of the primitive fraction as a mixture of molecularly distinct BCR::ABL1+ LSCs and BCR::ABL1-hematopoietic stem cells (HSCs) in variable ratio across patients, and guided their prospective isolation by a combination of CD26 and CD35 cell surface markers. We for the first time show that BCR::ABL1+ LSCs and BCR::ABL1- HSCs can be distinctly separated as CD26+CD35- and CD26-CD35+, respectively. In addition, we found the ratio of LSC/HSC to be higher in patients with prospective treatment failure compared to optimal responders, at diagnosis as well as following 3 months of TKI therapy. Collectively, this data builds a framework for understanding therapy response and adapting treatment by devising strategies to extinguish or suppress TKI-insensitive LSCs.

Single-cell multiomics analysis of chronic myeloid leukemia links cellular heterogeneity to therapy response

The advent of tyrosine kinase inhibitors (TKIs) as treatment of chronic myeloid leukemia (CML) is a paradigm in molecularly targeted cancer therapy. Nonetheless, TKI-insensitive leukemia stem cells (LSCs) persist in most patients even after years of treatment and are imperative for disease progression as well as recurrence during treatment-free remission (TFR). Here, we have generated high-resolution single-cell multiomics maps from CML patients at diagnosis, retrospectively stratified by BCR::ABL1IS (%) following 12 months of TKI therapy. Simultaneous measurement of global gene expression profiles together with >40 surface markers from the same cells revealed that each patient harbored a unique composition of stem and progenitor cells at diagnosis. The patients with treatment failure after 12 months of therapy had a markedly higher abundance of molecularly defined primitive cells at diagnosis compared to the optimal responders. The multiomic feature landscape enabled visualization of the primitive fraction as a mixture of molecularly distinct BCR::ABL1+ LSCs and BCR::ABL1-hematopoietic stem cells (HSCs) in variable ratio across patients, and guided their prospective isolation by a combination of CD26 and CD35 cell surface markers. We for the first time show that BCR::ABL1+ LSCs and BCR::ABL1- HSCs can be distinctly separated as CD26+CD35- and CD26-CD35+, respectively. In addition, we found the ratio of LSC/HSC to be higher in patients with prospective treatment failure compared to optimal responders, at diagnosis as well as following 3 months of TKI therapy. Collectively, this data builds a framework for understanding therapy response and adapting treatment by devising strategies to extinguish or suppress TKI-insensitive LSCs.

Persistent threat avoidance following negative reinforcement is not associated with elevated state anxiety.

Obsessive-Compulsive Disorder (OCD) is a debilitating illness consisting of obsessions and compulsions. OCD severity and treatment response are correlated with avoidant behaviors thought be performed to alleviate obsession-related anxiety. However, little is known about either the role of avoidance in the development of OCD or the interplay between anxiety states and avoidance behaviors. We have developed an instrumental negative reinforcement (i.e. active avoidance) paradigm in which mice must lever-press to avoid upcoming foot shocks. We show that mice (both sexes) can learn this task with high acquisition rates (75%) and that this behavior is largely stable when introducing uncertainty and modifying task structure. Furthermore, mice continue to perform avoidance responses on trials where lever pressing is not reinforced and increase response rates as they are maintained on this paradigm. With this paradigm, we did not find a relationship between negative reinforcement history and anxiety-related behaviors in well-established anxiety assays. Finally, we performed exploratory analyses to identify candidate regions involved in well-trained negative reinforcement using expression of the immediate early gene c-Fos. We detected correlated c-Fos expression in 1) cortico-striatal regions which regulate active avoidance in other paradigms and 2) amygdala circuits known to regulate conditioned defensive behaviors.Significance Statement Studies in patients with OCD suggest that compulsions are performed to avoid perceived threats and modulate anxiety tied to obsessions and/or compulsions. The negative reinforcement of avoidance and alleviated anxiety could therefore be a key driver of compulsive behaviors. However, there are still outstanding questions concerning the relationship between these two behaviors and the neural circuits involved in mediating negative reinforcement. We have developed an operant negative reinforcement paradigm in mice with discrete avoid and escape behaviors that can be learned without prior reward training with high throughput (75% acquisition) with responding that persists during nonreinforced trials. However, no differences were observed between negative reinforcement vs. unshocked and inescapably shocked controls, suggesting that continued negative reinforcement did not impact anxiety.

A detailed comparison of ethanol–diesel direct fuel blending to conventional ethanol–diesel dual-fuel combustion

Dual-fuel combustion is a well-known measure to enable the combustion of low-reactivity fuels (LRF) in compression-ignited engines with high thermal efficiency through a pilot injection of a high-reactivity fuel (HRF). In most cases, the LRF is introduced into the intake manifold and therefore premixed with the air before entering the combustion chamber during the intake stroke (premixed charge operation, PCO). In this work, this approach is investigated for bioethanol-diesel dual-fuel combustion using external and internal exhaust gas recirculation (EGR) to improve emissions and engine efficiency. In addition, PCO is compared to an alternative concept in which bioethanol and diesel are blended shortly upstream of the high-pressure pump (premixed fuel operation, PFO) at variable mixing ratios. The results show that higher ethanol shares of up to 70% can be achieved at low engine load when using PCO, while at medium and high load, the maximum energy share of ethanol is higher with PFO. While PCO is limited by engine knock, PFO rather suffers from the reduction in cetane number. In PCO, external and internal EGR allow for a reduction of unburned hydrocarbons (up to − 82%) and carbon monoxide (up to -60%), while nitrous oxide emissions are simultaneously lowered by up to − 65%. Both with and without EGR, PFO shows low emissions of unburned hydrocarbons and carbon monoxide (similar to conventional diesel combustion) and a significant reduction in nitrous oxide and soot formation. Brake thermal efficiency (BTE) drops in both modes compared to conventional diesel combustion, in PCO operation due to unburned and partially unburned fuel and in PFO due to increased friction in the high-pressure fuel pump caused by an increased fuel flow.

A review of 3D and 4D printable discontinuous and continuous fibre reinforcement polymers for soft robotics

A review of 3D and 4D printable discontinuous and continuous fibre reinforcement polymers for soft robotics

Investigating the effect of continuous and partial reinforcement in conceptual fear generalization

Fear generalization plays a major role in the acquisition and maintenance of anxiety disorders. In fear generalization, conditioned fear responses are observed for novel stimuli sharing perceptually or conceptually similar properties with the conditioned stimulus (CS). The reinforcement rates of the unconditioned stimulus (UCS) impact fear acquisition and generalization. Fear generalization can be studied using the category-based conditioning paradigm, where individuals are conditioned to members of a category rather than a single stimulus. The current study explored the effect of UCS reinforcement (i.e., continuous and partial) on conceptual fear generalization due to category-based similarity using a visual aversive UCS. The CSs were exemplars from four categories, i.e., animals, insects, household appliances, and tools. Thirty healthy participants underwent fear acquisition with exemplars from the four stimulus categories, presented with varying levels of UCS reinforcement (100%, 62.5%, and 37.5%). Subsequently, fear generalization was tested with novel unreinforced exemplars from each category. A significant effect of reinforcement on the UCS expectancy and CS-UCS contingency ratings was observed. UCS expectancy ratings increased with increasing certainty of UCS occurrence in the generalization phase. Our results may help to understand how fear generalizes to conceptually related stimuli based on the certainty of the UCS occurrence.

Predictive Factors of State Licensure Board Disciplinary Actions in Occupational Therapy.

One primary function of occupational therapy state licensure boards (SLBs) is the discipline of ethical misconduct by licensed occupational therapy practitioners. However, SLB sanctioning is poorly understood by practitioners, regulators, and the public. To identify predictors of occupational therapy practitioner sanctioning outcomes in the United States. Retrospective study; all public final consent orders and database entries provided online by SLBs were analyzed. Supervised gradient boosting machine learning, logistic regression, and contingency tables were used to generate odds ratios for variables associated with each sanctioning outcome. Multinomial testing was used to identify attribute overrepresentation among cases and national practitioner distributions. A total of 2,400 cases were analyzed across 47 states and Washington, DC. None. Numerous complaint and respondent attribute variables were collected from final consent orders and database entries. Complaint reason, practice setting, and complaint source had the highest influence on predicting sanction outcome; geographic region, number of complaints in a given case, and length of investigation in months were secondarily influential. Being male or a certified occupational therapy assistant was associated with higher odds of severe sanctioning outcomes. Disciplinary actions against occupational therapy practitioners were determined by numerous contextual factors; however, the most influential factors were complaint reason, practice setting, and complaint source. These results provide direction for exploring factors that predict sanctioning outcomes in the United States and also provide occupational therapy practitioners and SLBs a basis of applied outcomes that may improve implementation and education regarding clinical practice ethics. Plain-Language Summary: Occupational therapy state licensure boards (SLBs) are responsible for disciplining licensed occupational therapy practitioners for ethical misconduct. SLB sanctioning is poorly understood by practitioners, regulators, and the public. In this study, we identify the factors that predict the sanctioning outcomes of occupational therapy practitioners. The results may help state regulators, educators, and national associations more effectively act in a way that protects the public faith in occupational therapy services by providing contextualized information on practitioner behaviors that result in specific sanctioning outcomes. The study findings also provide occupational therapy practitioners and SLBs a basis of applied outcomes that may improve the implementation of and education regarding clinical practice ethics.

Development and Validation of an Assessment-Driven Behavioral Intervention for Primary Complex Motor Stereotypies in Young Children.

Complex motor stereotypies are rhythmic, repetitive, fixed, and non-goal directed movements (e.g., bilateral flapping/waving movements of the hands/arms). Movements typically begin in early childhood and can occur in otherwise normally developing ("primary") or autistic ("secondary") children. Stereotypies persist, occur multiple times a day, have prolonged durations, can be socially stigmatizing, and may lead to bullying and isolation. Prior behavioral treatment studies have focused on older children (ages 6-12) and report modest reductions in stereotypy (i.e., between 14% and 33%). The current study involves the functional assessment and treatment of five children with Primary Complex Motor Stereotypy using a modified awareness training procedure, differential reinforcement of other behavior, and schedule thinning in a nonconcurrent multiple baseline design. Results suggest a 99% reduction of motor stereotypy from baseline across all participants.

Prenatal Alcohol Exposure Disrupts Performance in a Differential Reinforcement of Low Rates Task Specifically in Adolescent Male Rats.

Prenatal alcohol exposure (PAE) can lead to a wide range of adverse effects in humans, including impaired self-control and increased impulsive behavior. Deficits in self-control can interfere with academic performance and have lasting impacts. In the present study, a rodent model of PAE was used to assess impulsivity through operant conditioning. Pregnant rats were assigned to one of three groups: ad-lib control (CON), pair-fed (PF), and alcohol-exposed (ALC). ALC rats were given a liquid diet containing 6% alcohol, PF rats were yoked to an ALC rat and given a CON liquid diet, and CON rats received ad libitum food. Operant conditioning was used to evaluate extinction in adolescents (Experiment 1) and differential reinforcement of low rates (DRL) in adolescents and adults (Experiment 2). PAE resulted in an increase in responses and resets during DRL testing, indicative of impaired self-control, an effect that was only observed in adolescent males. Females, regardless of age, did not show increased impulsivity following PAE. This indicates that children with PAE may exhibit attentional deficits similar to those with attention deficit hyperactivity disorder, with males at a higher risk.

Burst-like transcription of MYH7, allelic and contractile imbalance already in early stage hiPSC-cardiomyocytes indicate these as pathogenic factors in Hypertrophic Cardiomyopathy

Abstract Background Hypertrophic Cardiomyopathy (HCM) is caused by heterozygous mutations in sarcomeric proteins, which can cause hyper- or hypocontractiliy of cardiomyocytes. Previously we also observed highly variable force generation (contractile imbalance) among individual cardiomyocytes of HCM-patients with myosin (MYH7) or myosin-binding-protein-C mutations (MYBPC3), ranging from normal to highly altered values. Contractile imbalance is presumably caused by stochastic, burst-like transcription of mutant and wildtype allele, which induces unequal ratios of mutant vs. wildtype mRNA among individual cardiomyocytes. Variable force generation most likely is the result of also unequal fractions of mutated protein from cell to cell. Aim With this study we aimed to examine whether in addition to the effects of the mutation on sarcomere function, also allelic and contractile imbalance already exist at the beginning of disease development or whether both result from disease-related alterations in symptomatic HCM-patients. Methods and Results We studied this in patient-derived human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) with MYH7-mutation R723G as model for an early disease stage. These early, fetal-like cardiomyocytes developed typical HCM-related features like hypertrophy and increased myofibrillar disarray compared to WT-hiPSC-CMs. Calcium sensitivity was reduced, twitch kinetics were slowed down. To test whether MYH7 in these early-stage hiPSC-CMs also is transcribed in bursts or continuously, we performed RNA-fluorescence in situ hybridization (RNA-FISH). Nuclei without, with one and with two or more active transcription sites were observed which indicates stochastic, burst-like and independent transcription of the two MYH7-alleles. Ratios of mRNA from both alleles were quantified in individual cardiomyocytes by allele-specific single cell RT-PCR. We found highly variable ratios of mutated vs. wildtype mRNA among individual cardiomyocytes, similar to HCM-patient’s cardiac tissue, indicating unequal expression of mutant and wildtype mRNA from cell-to-cell. Furthermore, functional measurements on myofibrils from R723G-hiPSC-CMs revealed substantial variability in force generation at physiological calcium, compared to much smaller heterogeneity among WT-hiPSC-CMs. In addition, variability of twitch kinetics of intact hiPSC-CMs was also substantially increased among R723G- compared to WT-hiPSC-CMs. Altogether, this suggests that functional heterogeneity results from burst-like transcription in heterozygous HCM cardiomyocytes. Conclusions Our results in HCM-patient derived hiPSC-cardiomyocytes with a fetal-like developmental stage suggest that allelic and contractile imbalance among individual cardiomyocytes together with the mutation are present at the beginning of the disease. Thus, they most likely are exacerbating factors that contribute development of HCM hallmarks.

Ultrasound-guided percutaneous microwave ablation for metabolic-associated fatty liver disease-related hepatocellular carcinoma (HCC) versus hepatitis virus B-related HCC: a propensity score matching study

Objectives To compare the long-term outcomes of microwave ablation (MWA) for primary hepatocellular carcinoma (HCC) in patients with metabolic-associated fatty liver disease (MAFLD) with those infected by hepatitis virus B (HBV). Methods The clinical data of HCC patients under the treatment of MWA were analyzed retrospectively between 2010 and 2021 at Chinese PLA General Hospital. Patients were divided into MAFLD-HCC and HBV-HCC group according to the chronic liver disease etiology. The propensity score matching (PSM) was performed to reduce the interference of confounders. The primary outcomes were overall survival (OS), recurrence-free survival (RFS), cancer-specific survival (CSS) and intrahepatic distant recurrence (IDR). Results A total of 648 patients (age range, 18–91 years) with 1019 lesions were enrolled including 601 with HBV-HCC and 47 with MAFLD-HCC. After a variable ratio of 1:n ≤ 4 PSM, 100 patients were included in the HBV-HCC and 41 in the MAFLD-HCC group. No statistical differences in OS and CSS (p = 0.880 and p = 0.980, respectively) were observed between the two groups in the matched cohort, while MAFLD-HCC exhibited better RFS and lower IDR rates compared to HBV-HCC (p = 0.043 and p = 0.041, respectively). Additionally, MAFLD-HCC generated lower ascending range in the liver function indexes like ΔALT (46.7 vs. 98.5, p < 0.001), ΔTBIL (1.9 vs. 7.5, p = 0.001) and ΔAST (38.1 vs. 148.6, p < 0.001) than HBV-HCC after MWA. Conclusions MWA is an effective treatment for HCC patients with MAFLD. The recurrence prognosis of MAFLD-HCC was better than HBV-HCC and the degree of liver injury after MWA was lower.

Evaluation of resurgence following differential reinforcement of alternative behavior with and without extinction in a human operant model.

One of the most common treatments for severe challenging behavior involves placing the challenging behavior on extinction and differentially reinforcing an alternative response (DRA). However, extinction is not always feasible and may be unsafe or impractical to implement in some circumstances. Thus, implementing a DRA without extinction intervention may be necessary for some cases. Currently, the extent to which DRA without extinction produces durable treatment outcomes, particularly as it relates to the resurgence of challenging behavior, is unclear. The present study investigated resurgence following DRA with and without extinction using a three-phase resurgence evaluation in a translational human operant model with college students as participants. All participants demonstrated resurgence across both experimental groups. Although there were no statistically significant differences in the prevalence, magnitude, or persistence of resurgence between groups, levels of resurgence magnitude were relatively higher in the DRA-without-extinction group than in the DRA-with-extinction group. Clinical implications of these findings and directions for future human operant investigations of resurgence are discussed.

Investigating the Anisotropic Mechanical Behaviour of Steel Fibre-Reinforced Aluminium-Base Composites

Base metals are often reinforced with fibres to improve their mechanical behaviour; however, it is imperative to decide the range of fibres orientation that would yield favourable strength. In this work, using sand casting method, aluminium is reinforced with galvanized steel fibres at different orientations with the aim of investigating the anisotropic mechanical behaviour of the composites. The fibre orientations considered are 0°, 30°, 60° and 90°; while the mechanical properties evaluated are impact energy, tensile, compressive and fatigue properties. Unreinforced aluminium exhibits impact energy, elongation-at-fracture, ultimate tensile strength, and maximum compressive strength of 5.15 J, 15.88%, 72.56 MN/m2, and 231.13 MN/m2, respectively. With deviation of composite fibre orientation from 0° to 30°, 60° and 90°, impact energy decreases from 8.68 to 5.56, 4.75 and 4.61 J; elongation-at-fracture decreases from 24.58 to 17.91, 12.20 and 11.87%; ultimate tensile strength decreases from 132.70 to 89.17, 63.67 and 60.34 MN/m2; and maximum compressive strength decreases from 310.66 to 251.06, 226.91 and 209.93 MN/m2. At fatigue stress amplitude of 850 MN/m2, the fatigue life of unreinforced specimen is 26 numbers of cycles-to-failure; while the deviation of composite fibre orientation from 0° to 30°, 60° and 90° yielded reduction in fatigue life from 64 to 36, 20 and 14 numbers of cycles-to-failure. Also, reduction in fatigue stress amplitude was found to increase the fatigue life of the specimens. The fatigue limit (or endurance limit) of unreinforeced specimen, and composite specimen having 0°, 30°, 60° and 90° fibre orientations are found to be 40, 70, 45, 35 and 25 MN/m2, respectively; and the corresponding fatigue life are observed to be 35480, 199518, 112195, 10021 and 5297 numbers of cycles-to-failure, respectively. The findings in this work show that specimens with 0° fibre orientation have the highest endurance of deformation before fracture, followed by specimens with 30° fibre orientation, unreinforced specimens, specimens with 60° fibre orientation and specimens with 90° fibre orientation. This could be attributed to the fact that 0° fibre orientation offers continuous reinforcement spanning the longitudinal axis of the specimens, while fibre orientation from 30° to 90° offer areas of different degrees of shear stress concentration at fibre-matrix contacts aiding fibre-matrix debonding and crack propagation. In conclusion, this work shows that orientation of steel fibre reinforcement in aluminium matrix could be varied to achieve ranges of mechanical properties and performance needed for different practical applications.

Formulating PEO-polycarbonate blends as solid polymer electrolytes by solvent-free extrusion

Liquid electrolytes are currently state-of-the-art for commercial Li-ion batteries. However, their use implicates inherent challenges, including safety concerns associated with flammability, limited thermal stability, and susceptibility to dendrite formation on the lithium metal anode, that can compromise the battery lifespan. Solid-state polymer electrolytes offer an alternative to conventional liquid electrolytes, aiming to mitigate safety, stability, and performance drawbacks. This study investigates the preparation and the comprehensive characterization of polyethylene oxide (PEO) and polycarbonate (PC) blends obtained through extrusion process. The process is solvent-free and easily scalable at the industrial level; it grants the efficient dispersion and mixing of PEO and PC. Blends at different ratios of PEO (Mw of 4 × 105 and 4 × 106 g mol˗1) and two types of PCs (namely, polyethylene and polypropylene carbonate) including lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) are prepared. Optimization and investigation of the relative effects between the application of different PCs and the variable ratios of PEO/PCs on the mechanical, morphologic and electrochemical properties of the final polymeric membranes is carried out for future applications of these systems, as efficient electrolytes in all-solid-state lithium batteries.

Assessment and Treatment of Target Behavior Maintained by Social Avoidance.

Past research has identified that some individuals with intellectual and developmental disabilities who engage in target behavior (e.g., aggression, self-injury) maintained by negative reinforcement engage in the behavior to escape or avoid social interaction specifically (i.e., social avoidance). However, assessment and treatment strategies for this function are understudied when compared to target behavior maintained by other forms of negative reinforcement. The current study builds on this limited research and demonstrates (a) a replication of functional analysis conditions and a negative reinforcement latency assessment to identify the specific types of social interaction that evoke target behavior, and (b) an intervention that includes stimulus fading, social conditioning, and differential reinforcement for five participants with autism spectrum disorder. Participant target behavior decreased within the intervention phase for four out of five participants. The implications of strategies to guide the use of antecedent-based treatment strategies are discussed for target behavior maintained by social avoidance.