Doctoral Degree Granting Institutions: Recent submissions
Now showing items 21-40 of 2098
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Gut microbiota links with cognitive impairment in amyotrophic lateral sclerosis: A multi-omics studyRecently, cognitive impairments (CI) and behavioral abnormalities in patients with amyotrophic lateral sclerosis (ALS) have been reported. However, the underlying mechanisms have been poorly understood. In the current study, we explored the role of gut microbiota in CI of ALS patients. We collected fecal samples from 35 ALS patients and 35 healthy controls. The cognitive function of the ALS patients was evaluated using the Edinburgh Cognitive and Behavioral ALS Screen. We analyzed these samples by using 16S rRNA gene sequencing as well as both untargeted and targeted (bile acids) metabolite mapping between patients with CI and patients with normal cognition (CN). We found altered gut microbial communities and a lower ratio of Firmicutes/ Bacteroidetes in the CI group, compared with the CN group. In addition, the untargeted metabolite mapping revealed that 26 and 17 metabolites significantly increased and decreased, respectively, in the CI group, compared with the CN group. These metabolites were mapped to the metabolic pathways associated with bile acids. We further found that cholic acid and chenodeoxycholic acid were significantly lower in the CI group than in the CN group. In conclusion, we found that the gut microbiota and its metabolome profile differed between ALS patients with and without CI and that the altered bile acid profile in fecal samples was significantly associated with CI in ALS patients. These results need to be replicated in larger studies in the future.
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The role of self-esteem and emotion regulation in the associations between childhood trauma and mental health in adulthood: a moderated mediation modelBackground: High levels of childhood trauma (CT) have been observed in adults with mental health problems. Herein, we investigated whether self-esteem (SE) and emotion regulation strategies (cognitive reappraisal (CR) and expressive suppression (ES)) affect the association between CT and mental health in adulthood, including depression and anxiety symptoms. Methods: We performed a cross-sectional study of 6057 individuals (39.99% women, median age = 34 y), recruited across China via the internet, who completed the Patient Health Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder-7 (GAD-7), Childhood Trauma Questionnaire (CTQ), Self-esteem Scale (SES), and Emotion Regulation Questionnaire (ERQ). Multivariate linear regression analysis and bias-corrected percentile bootstrap methodologies were used to assess the mediating effect of SE, and hierarchical regression analysis and subgroup approach were performed to examine the moderating effects of emotion regulation strategies. Results: After controlling for age and sex, we found that (1) SE mediated the associations between CT and depression symptoms in adulthood (indirect effect = 0.05, 95% confidence interval [CI]: 0.04-0.05, 36.2% mediated), and CT and anxiety symptoms in adulthood (indirect effect = 0.03, 95% CI: 0.03-0.04, 32.0% mediated); (2) CR moderated the association between CT and SE; and (3) ES moderated the association between of CT and mental health in adulthood via SE, and such that both the CT-SE and SE-mental health pathways were stronger when ES is high rather than low, resulting the indirect effect was stronger for high ES than for low ES. Conclusions: These findings suggested that SE plays a partially mediating role in the association between CT and mental health in adulthood. Furthermore, ES aggravated the negative effect of CT on mental health in adulthood via SE. Interventions such as emotional expression training may help reduce the detrimental effects of CT on mental health. Trial registration: The study was registered on http://www.chictr.org.cn/index.aspx and the registration number was ChiCTR2200059155.
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The role of ALDH2 rs671 polymorphism and C-reactive protein in the phenotypes of male ALS patientsBackground: The aldehyde dehydrogenase 2 (ALDH2) rs671 (A) allele has been implicated in neurodegeneration, potentially through oxidative and inflammatory pathways. The study aims to investigate the effects of the ALDH2 rs671 (A) allele and high sensitivity C-reactive protein (hs-CRP) on the clinical phenotypes of amyotrophic lateral sclerosis (ALS) in male and female patients. Methods: Clinical data and ALDH2 rs671 genotype of 143 ALS patients, including 85 males and 58 females, were collected from January 2018 to December 2022. All patients underwent assessment using the Chinese version of the Edinburgh Cognitive and Behavioral ALS Screen (ECAS). Complete blood count and metabolic profiles were measured. Clinical and laboratory parameters were compared between carriers and non-carriers of the rs671 (A) allele in males and females, respectively. The significant parameters and rs671 (A) Allele were included in multivariate linear regression models to identify potential contributors to motor and cognitive impairment. Mediation analysis was employed to evaluate any mediation effects. Results: Male patients carrying rs671 (A) allele exhibited higher levels of hs-CRP than non-carriers (1.70 mg/L vs. 0.50 mg/L, p = 0.006). The rs671 (A) allele was identified as an independent risk factor for faster disease progression only in male patients (β = 0.274, 95% CI = 0.048-0.499, p = 0.018). The effect of the rs671 (A) allele on the executive function in male patients was fully mediated by hs-CRP (Indirect effect = -1.790, 95% CI = -4.555--0.225). No effects of the rs671 (A) allele or hs-CRP were observed in female ALS patients. The effects of the ALDH2 rs671 (A) allele and the mediating role of hs-CRP in male patients remained significant in the sensitivity analyses. Conclusion: The ALDH2 rs671 (A) allele contributed to faster disease progression and hs-CRP mediated cognitive impairment in male ALS patients.
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Association between cardiac autonomic dysfunction, cognitive impairment, and survival in patients with amyotrophic lateral sclerosisPurpose: The aim of this study was to investigate the relationship between cardiac autonomic dysfunction, cognitive impairment, and survival in patients with amyotrophic lateral sclerosis (ALS). Methods: The heart activity of 65 patients with ALS (28 with normal cognition [ALS-CN]; 37 with impaired cognition [ALS-CI]) and 38 healthy controls (HCs) was measured by 24-h Holter monitoring. Heart rate (HR) measures and heart rate variability (HRV) parameters were compared between the three study groups and, additionally, correlated with five Edinburgh Cognitive and Behavioral ALS Screen (ECAS) domains in the ALS subgroups. Age, gender, and educational level were adjusted. Factors associated with cognitive status were assessed using logistic regression. Survival predictors in patients with ALS were analyzed using the Kaplan-Meier estimator and Cox regression. Results: Compared to the HCs, patients with ALS-CI exhibited lower RRI (R-R-interval; P = 0.017), SDNN (standard deviation of all normal RR intervals; P = 0.013), SDNN Index (P = 0.044), and VLF power (very low-frequency power; P = 0.012). Total power was reduced in the ALS-CI group compared to the HCs (P = 0.036) and ALS-CN group (P = 0.048). In patients with ALS-CN, language negatively correlated with mean HR (P = 0.001) and positively with the RRI (P = 0.003), SDNN (P = 0.001), SDANN (standard deviation of the average NN intervals; P = 0.005), total power (P = 0.006), VLF power (P = 0.011), and low-frequency power (P = 0.026). Visuospatial function correlated positively with the SDNN Index (P = 0.041). In patients with ALS-CI, executive function (P = 0.015) and ECAS total score (P = 0.009) negatively correlated with the RMSSD (square root of mean sum-of-squares of differences between adjacent NN intervals), while visuospatial function correlated positively with normalized LF value (LFnu; P = 0.049). No associations were observed between the other cognitive domains and any of the 14 HRV/HR measures in patients with either ALS-CI or ALS-CN. SDNN ≤ 100 ms was linked to cognitive impairment (P = 0.039) and also showed a borderline association (P = 0.066) with poorer survival, while cognitive impairment (P = 0.010) was significantly linked to worse outcomes. Conclusions: Patients with ALS with cognitive impairment demonstrated reduced cardiac autonomic modulations and altered cognitive autonomic associations. Cognitive impairment was linked to reduced survival, with baseline SDNN ≤ 100 ms identified as a potential marker.
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Engineering Generalized Protein-Based Biosensors for Molecular Detection and Clinical ApplicationsProtein-based conformational switches serve as powerful tools for the construction of biosensors and for the control of cellular processes. These proteins feature a binding domain that recognizes a specific analyte and is coupled to an output domain in such a way that the binding event causes the output domain to provide an observable signal. These signals can either be turn-on of fluorescence, luminescence, or enzymatic activity or consist of the sensor changing its color. A challenge in constructing these protein switches is finding binding domains capable of relaying a ligand binding event to the conformational change of an output domain. Generalized binding domains can address these challenges by providing a scaffold that can easily be modified to detect a different ligand. These generalized binding domains are small proteins with modifiable residues that can be selected to bind a ligand of choice, usually through phage display and similar selection techniques. Here, we present two approaches to make generalized protein switches. In the first approach, antibody mimetics nanobodies and monobodies are inserted in fluorescent proteins such that binding of their ligand causes an increase in fluorescence. This technique, named adaptable turn-on maturation (ATOM), was used to develop biosensors for WD-40 repeat protein 5 (WDR5), c-Abl src homology 2 (SH2) domain, hRas, postsynaptic density protein 95 (PSD95), gephyrin, HOMER1, and mCherry for use in mammalian cells. ATOM is, therefore, compatible with a variety of ligands due to its input domain being a generalized binding domain. Additionally, the ATOM mechanism can be used to convert many fluorescent proteins into biosensors. For demonstration, we made biosensors from Clover, mTurqoise, mTagRFP-t, mStayGold, mBaoJin, and GCaMP6s. In the second approach, we develop a luminescent protein switch from the enzyme nanoluciferase (nLucAFF) that switches color from green to blue upon DNA binding. We show that DNA-based devices can then be used to detect various ligands and relay that event to nLucAFF, which provides an output easily quantifiable by a cell phone. The nLucAFF protein was used to detect DNA sequences amplified from cytomegalovirus (CMV), dengue, and nCoV. Additionally, aptamers binding to serotonin and aptamers were used to detect these molecules by directing the nLucAFF color change. The initial version of nLucAFF was slow, dim, and had low sensitivity. These drawbacks were resolved in the next version, nLucAFF2, to achieve turn-on within 5 minutes and detect ligands down to 40 pM with a cell phone camera. The last chapter combines two ligand-binding domains to activate a small cytotoxic RNase, barnase, and paves the way for the development of multi-input protein switches that can potentially be generalized ligand-binding domains.
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Nanobody development for therapeutically targeting Vacuolar H+-ATPasesThe vacuolar H+-ATPase (V-ATPase, V1Vo) is a dedicated proton pump that is highly conserved amongst eukaryotes, and is necessary for pH homeostasis within subcellular compartments. The V-ATPase consists of two subcomplexes: the soluble V1 responsible for hydrolyzing ATP, and the membrane integral Vo responsible for proton translocation across membranes. V1 and Vo are each comprised of multiple subunits, A3B3CDE3FG3 and ac8c'c"def Voa1 respectively. Many basic cellular functions depend on the differential pH gradient across cellular membranes to operate properly, making regulation of V-ATPases through "reversible disassembly" immensely important. Global loss of V-ATPase activity is lethal to all mammalian cell types, while aberrant activity and incorrectly localized V-ATPase results in various disease states. Current therapeutics struggle to target specific V-ATPase populations, and as a potential solution to this problem we generated 94 nanobody clones against the yeast nanodisc reconstituted Vo (VoND). Nanobodies (Nbs) are the small 15 kDa VHH domain isolated from heavy-chain only antibodies that are known for their high specificity. In this dissertation we describe the characterization of three α-yeast VoND Nbs, N27, N125, and N2149. Using an ATPase assay, we found that N27, but not N125 or N21149, fully inhibited the activity of assembled V-ATPase. Contrastingly, N2149, but not N27 or N125, was found to inhibit the assembly of the two subcomplexes. BLI was used to identify the binding affinity of each Nb, with affinities being observed in the nM-pM range. High-resolution structures obtained from cryoEM revealed the subunit specificity of each Nb, with N27 and N125 found to bind the c-ring in different stoichiometries, and N2149 found to bind the d subunit. Furthermore, we determined that N125 has cross affinity for the human enzyme. Overall, this study provides evidence that novel nanobody mediated inhibition of assembly or activity of V-ATPases is an effective technique with broader implications of nanobody development into therapeutics.
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Nanotherapeutics for Immune Modulation in SepsisDue to its complexity and heterogeneity, managing immune dysregulation in sepsis poses a significant clinical challenge. Thus, there is great demand to both improve our understanding of mediators of immune dysregulation in sepsis and develop nuanced therapeutic approaches to provide precise immune modulation for sepsis treatment. This thesis first investigates the novel phenomenon of cytokine charge disparity as a potential regulator of cytokine function. Then, two novel telodendrimer immune modulation approaches are presented as a personalized medicine strategy for sepsis. Through extensive database and literature review, we have established cytokine charge disparity as a potential mechanism for immune regulation. Using our versatile telodendrimers (TDs), we then optimized and validated our TD nanotrap approach for effective and selective targeting of plasma cytokines. Our lead selective TD nanotraps displayed charge selective cytokine targeting and our lead pan-affinitive TD nanotrap demonstrated superior cytokine removal efficacy compared to commercial resin control. Additionally, pan-affinitive TD nanotrap maintained efficacy across a wide range patient immune status, indicating promising therapeutic potential to reduce mortality risk associated with overwhelming cytokine profiles. To further expand our immune modulation tool set for sepsis treatment, we optimized our TD nanodrug for delivery of dimethyl itaconate (ITA) to control both hyperinflammation and pyroptosis. Encapsulating ITA into TD nanoparticles (ITA:TDNPs) resulted in a sustained-release profile and improved biocompatibility compared to free ITA. ITA:TDNPs more effectively inhibited both LPS- and LTA-induced inflammation and pyroptosis in macrophages compared to ITA or TDNP alone. Finally, ITA:TDNPs demonstrated superior therapeutic efficacy in both an IV LPS and polymicrobial cecal slurry sepsis model compared to individual therapies. Collectively, we have uncovered a novel phenomenon of cytokine charge disparity and validated it as a potential mechanism to regulate cytokine activity, as well as established it as targeting mechanism for effective immune modulation via charge selective TD nanotrap. We further developed an immune modulating TD nanodrug for ITA delivery to control both hyperinflammation and immune cell pyroptosis in sepsis. Through precise targeting of immune dysregulation in sepsis using a systematic multimodal TD therapeutic approach for personalized medicine, we may successfully improve patient outcomes in this devastating disease.
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Mechanism of Mitochondria-Induced Muscle Atrophy During AgingMitochondrial dysfunction is strongly associated with aging-related degenerative diseases including muscle atrophy. However, whether bioenergetic defects are the sole drivers of mitochondria-induced muscle atrophy remains unknown. The Chen lab discovered that various forms of mitochondrial damage can disrupt protein import, leading to the toxic accumulation of unimported mitochondrial precursors in the cytosol. This causes a stress termed mitochondrial Precursor Over-accumulation Stress (mPOS). A mouse model of mPOS was developed in which the mitochondrial inner membrane protein, ANT1, was overexpressed to saturate the protein import machinery. Ant1Tg/+ mice were found to have a severe muscle wasting phenotype. The overarching goal of this dissertation is to investigate the mechanism by which mPOS drives muscle wasting and its implications for normative muscle aging. The findings presented in this thesis led to three conclusions. First, we identified a novel mitochondria-to-lysosomal proteostatic axis through which mPOS induces lysosomal damage. Lysosomal damage subsequently causes the release proteolytic enzymes, which leads to excessive protein degradation and subsequent progressive muscle atrophy. Importantly, we found that this pathway operates independently of mitochondrial respiratory complex activity and reactive oxygen species (ROS) production. Second, we demonstrated the presence of mPOS in physiologically aged muscle. Sarcopenic muscle exhibited phenotypes similar to those found in Ant1Tg/+ mice, evidenced by overlapping transcriptional and proteomic profiles, and lysosomal damage. These findings indicate that mitochondria-induced changes to autophagic activity may play a central role in the pathogenesis of sarcopenia. However, considering the overall protein content of muscle is elevated during aging, we propose that reduced protein quality, rather than absolute protein content, drives sarcopenia. We therefore termed this phenomenon Muscle Atrophy Independent of Protein Content (MAIPC). Finally, we explored additional cellular factors that affect proteostasis and muscle mass maintenance. We found that the GCN2 kinase, a well-established activator of the Integrated Stress Response (ISR), plays a role in protecting myofibers from mPOS-induced stress and muscle wasting in Ant1Tg/+ muscle. Interestingly, we found that this effect is ISR-independent. The data presented in this dissertation provide valuable insights into the mechanistic role of mitochondrial dysfunction in both normative aging and chronic muscle wasting conditions. Our findings conclude that mitochondria-induced muscle atrophy is induced by mechanisms that extend beyond bioenergetic defects. By characterizing these alternative pathways, this work opens new avenues for therapeutic strategies targeting mitochondrial stress in chronic muscle wasting conditions.
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A REVIEW OF RECENT STUDIES ON DIFFERENTIAL REINFORCEMENT DURING SKILL ACQUISITION IN EARLY INTERVENTIONAlthough the use of differential reinforcement has been recommended in previous investigations and in early intervention curriculum manuals, few studies have evaluated the best method for providing differential reinforcement to maximize independent responding. This paper reviews previous research on the effectiveness of differential reinforcement as treatment and describes important areas of future research.
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THE EFFECTS OF VIDEO MODELING WITH VOICEOVER INSTRUCTION ON ACCURATE IMPLEMENTATION OF DISCRETE‐TRIAL INSTRUCTIONThe present study replicates and extends previous research on the use of video modeling (VM) with voiceover instruction to train staff to implement discrete-trial instruction (DTI). After staff trainees reached the mastery criterion when teaching an adult confederate with VM, they taught a child with a developmental disability using DTI. The results showed that the staff trainees' accurate implementation of DTI remained high, and both child participants acquired new skills. These findings provide additional support that VM may be an effective method to train staff members to conduct DTI.
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Evaluating the Emergence of Reverse Intraverbals in Children with AutismVerbal behavior plays a fundamental role in the development of complex social and communication skills. Many children diagnosed with autism spectrum disorder exhibit profound deficiencies in intraverbal repertoires and the development of social relationships. Recent studies that investigated the effects of intraverbal training on the emergence of reverse intraverbals produced mixed results (e.g., Perez-Gonzalez et al., Journal of Applied Behavior Analysis 40:697-701, 2007)). In the current study, a multiple-probe design across four participants with autism was used to evaluate the effects of intraverbal training on the emergence of reverse intraverbals. Intraverbal training consisted of multiple exemplars taught concurrently, bidirectional stimulus-response teaching formats, general case analysis, reinforcement, and a constant prompt delay (CPD) procedure. Participants were trained on intraverbal targets and probes were conducted to assess emergence of untaught reverse intraverbals. Three participants demonstrated the emergence of reverse intraverbals as a result of the intraverbal training procedures. Social validity and maintenance of target responses and emergent reverse intraverbals were assessed.
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Using Video Modeling with Voiceover Instruction Plus Feedback to Train Staff to Implement Direct Teaching ProceduresDirect teaching procedures are often an important part of early intensive behavioral intervention for consumers with autism spectrum disorder. In the present study, a video model with voiceover (VMVO) instruction plus feedback was evaluated to train three staff trainees to implement a most-to-least direct (MTL) teaching procedure. Probes for generalization were conducted with untrained direct teaching procedures (i.e., least-to-most, prompt delay) and with an actual consumer. The results indicated that VMVO plus feedback was effective in training the staff trainees to implement the MTL procedure. Although additional feedback was required for the staff trainees to show mastery of the untrained direct teaching procedures (i.e., least-to-most and prompt delay) and with an actual consumer, moderate to high levels of generalization were observed.
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Using Video Modeling with Voice-over Instruction to Train Public School Staff to Implement a Preference AssessmentThe identification of putative reinforcers is a critical component of programming for individuals with disabilities. A multiple stimulus without replacement preference assessment is one option for identifying putative reinforcers; however, staff must be trained on the steps necessary to conduct the assessment for it to be useful in practice. This study examined the effectiveness of using video modeling with voice-over instruction (VMVO) to train two public school staff to conduct this assessment. Results demonstrate that VMVO was effective in training, producing generalized responding, maintenance, and high social validity ratings.
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Evaluation of Computer-Based Training to Teach Adults Visual Analysis Skills of Baseline-Treatment GraphsThe primary method of data analysis in applied behavior analysis is visual analysis. However, few investigations to date have taught the skills necessary for accurate visual analysis. The purpose of the present study was to evaluate computer-based training on the visual analysis skills of adults with no prior experience. Visual analysis was taught with interactive computer-based training that included written instructions and opportunities for practice with textual feedback. Generalization of participant skills from simulated to handwritten and authentic data graphs was programmed for and assessed during the study. A multiple-baseline design was used across visual analysis properties (i.e., variability, level, and trend), with continuous overall intervention effect generalization probes, replicated across 4 participants to evaluate computer-based training for accurate visual analysis of A-B graphs. The results showed that all participants accurately visually analyzed A-B graphs following the computer-based training for variability, level, trend, and overall intervention effect. These visual analysis skills generalized to handwritten and authentic data graphs and maintained approximately 1 day, 1 week, 2 weeks, and 1 month following mastery of each property for all participants. Implications of the results suggest that computer-based training improved accurate visual analysis skills for adults with no prior experience.
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Reinforcer Choice on Skill Acquisition for Children with Autism Spectrum Disorder: a Systematic ReplicationProviding students with autism spectrum disorder (ASD) a choice of putative reinforcers during learning trials may confer advantage during skill acquisition programming. However, such advantage should not be assumed and may not be associated with the most efficient instructional arrangement. In the current study, we taught labels of common object or conditional discriminations to participants with ASD and evaluated efficiency of instruction across child- and experimenter-choice instructional conditions. The results indicated that the most efficient acquisition was observed during the experimenter-choice condition for both participants.
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Reinforcer Choice as an Antecedent Versus Consequence During Skill AcquisitionProviding a choice of reinforcers is a commonly used strategy with children with autism spectrum disorder; however, less is known about the differential effectiveness and efficiency of providing choices before or after responding during acquisition tasks. Therefore, we evaluated reinforcer choice using untaught targets prior to and following responding. Results showed faster acquisition of targets in the consequence condition for 2 of 3 participants. These data provide preliminary support that providing choice prior to responding may not result in the most efficient acquisition for some individuals.
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Comparing Stimulus Equivalence-Based Instruction to a Video Lecture to Increase Religious Literacy in Middle-School ChildrenBeing familiar with world religions and their diverse practices is referred to as religious literacy. The present study compared the effects of stimulus equivalence-based instruction (EBI) and video lecture (VL) to increase religious literacy in middle-school students; 10 participants were assigned to either the EBI or the VL group. Participants in the EBI group were taught five 6-member equivalence classes using match-to-sample (MTS) software on a computer. Within each class of (1) Judaism, (2) Islam, (3) Christianity, (4) Hinduism, and (5) Buddhism, the visual stimulus members were (A) name of the religion, (B) major religious symbol, (C) sacred text, (D) notable religious figure, (E) name of religious service leader, and (F) notable celebrated holiday. The VL participants were given an opportunity to complete a fill-in written worksheet while viewing a video lecture about the 5 religions using the same stimuli as the EBI group. Participant responding in each group was compared across worksheet, oral, and MTS pretests and posttests. The results showed that 5 of 5 participants in the EBI group formed equivalence classes but only 1of 5 did so in the VL group. Class-consistent responding generalized to oral vignettes to a greater degree for the EBI participants than for the VL participants. In addition, at an approximately 2-week follow-up, EBI participants maintained class-consistent responding to a greater degree than VL participants did. Duration measures showed that even though EBI was more effective, EBI training did require more time than the VL did. Although not explicitly programmed for, social distance survey scores showed that participants improved equally in their ratings of the acceptability of people from other faiths following training, regardless of training type. Thus, EBI may be an effective method to teach schoolchildren about religious literacy.
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Evaluation of Manualized Instruction to Train Staff to Implement a Token EconomyAll components of behavioral skills training may not be necessary to effectively train staff to implement behavior-analytic technologies with children with disabilities. This study evaluated manualized instruction to train inexperienced staff to implement a token economy with a confederate and collect data on learner responding. A nonconcurrent multiple-baseline design across staff trainees was used to evaluate the effectiveness of manualized instruction to increase the staff trainees' accurate implementation of a token economy. Additionally, a modified general case analysis was conducted to identify potential child behaviors. Multiple-exemplar training of these behaviors was presented in random order during sessions. Following the use of the manualized instruction, staff trainees' accurate implementation of a token economy and data collection on confederate responding increased, the skills generalized from a confederate to a child with autism spectrum disorder, and the skills maintained 1 month following training.
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A Comparison of Video Modeling and Video Prompting by Adolescents with ASDVideo-based instruction has been effective in teaching a range of skills, including functional living skills, to individuals with autism spectrum disorder. Few studies have compared the efficacy and efficiency across video modality-specifically, comparing video modeling to video prompting. Consequently, practitioners have little empirical guidance when selecting between procedural variations of video-based instruction. Using an adaptive alternating-treatments design with a baseline, we evaluated the comparative effectiveness of point-of-view video modeling and video prompting on the percentage of meal preparation tasks completed correctly and on-task behavior with 4 adolescents with autism spectrum disorder. We found video modeling to be effective and efficient in the acquisition of meal preparation skills across 3 of the 4 participants. Across participants, video prompting resulted in more errors than video modeling did. Skills generalized to an untrained location and were maintained at a 3-week follow-up. Stakeholders reported procedures, goals, and outcomes as socially valid.
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Comparing Skill Acquisition Under Different Stimulus Set Sizes With Adolescents With Autism Spectrum Disorder: A ReplicationA number of variables may influence the effectiveness and efficiency of skill acquisition. One variable that may be important is set size. The current study replicated and extended Kodak et al. (2020, "A Comparison of Stimulus Set Size on Tact Training for Children With Autism Spectrum Disorder," Journal of Applied Behavior Analysis, 53(1), 265-283) by evaluating the stimulus set size that led to the most efficient skill acquisition for 2 adolescents with autism spectrum disorder. More specifically, we evaluated tact acquisition in stimulus set sizes of 3, 6, and 12. The set sizes of 3 and 6 stimuli were associated with the most efficient acquisition, whereas the set size of 12 stimuli was not.