Impairment in cognitive control in alcohol use disorder (AUD) contributes to difficulty controlling alcohol use and, in many populations, difficulties with emotion regulation. However, the most ...reliable and robust marker of clinically-relevant deficits in cognitive control in AUD is unclear. Our aims were to measure relationships between BOLD signal during a Stroop task and AUD severity and change in BOLD signal and change in drinking over three weeks. We also aimed to explore the relationships between BOLD signal and subjective negative affect. Thirty-three individuals with AUD underwent a multisensory Stroop task during functional magnetic resonance imaging (fMRI), as well as a battery of neuropsychological tests and self-report assessments of negative affect and AUD severity. Greater activation in temporal gyrus and cerebellum during incongruent trials compared to congruent trials was observed, and percent signal change (incongruent minus congruent) in both clusters was positively correlated with AUD severity and self-reported negative affect. Neuropsychological task performance and self-reported impulsivity were not highly correlated with AUD severity. Hierarchical regression analyses indicated that percent signal change (incongruent minus congruent) in cerebellum was independently associated with negative affect after controlling for recent and chronic drinking. In a subset of individuals (
n
= 23) reduction in cerebellar percent signal change (incongruent minus congruent) was correlated with increases in percent days abstinent over 3 weeks. BOLD activation during this Stroop task may therefore be an important objective marker of AUD severity and negative affect. The potential importance of the cerebellum in emotion regulation and AUD severity is highlighted.
Recent neuropsychological studies have distinguished deficits in verbal working memory, verbal memory, and confrontation naming from other neuropsychological domains as specifically related to the ...severity of auditory verbal hallucinations (AVH) in schizophrenia (
Gisselgard et al., 2014
;
Siddi et al., 2017
). To extend this research, it was hypothesized that AVH severity would be related only to measures within the language domain and the test battery was augmented with the CTOPP2 and COWAT…define? to more comprehensively define the language processing functions most predictive of AVH. A neuropsychological test battery was administered to a group of adult patients diagnosed with schizophrenia and schizoaffective disorder (N = 30), who continued to experience AVH despite clinical treatment. Multiple regression analyses demonstrated that poorer performance on measures of verbal working memory and verbal immediate memory significantly predicted greater AVH severity. Going beyond the prior studies, it was also shown that greater impairment of semantic fluency and lesser impairment in delayed general memory were also significant predictors of AVH. Intellectual ability and executive functioning, considered as covariates, were not significant predictors and their inclusion in regression analyses did not affect the pattern of results. Lastly, when cognitive predictors were accounted for, a trend toward an effect of medication (assessed as olanzapine equivalents) emerged such that higher dose predicted less severe AVH. Taken together, better performance on measures of linguistic processes associated with verbal working memory, semantic fluency and verbal learning predicts less severe AVH, perhaps most consistent with limited capacity language processing models. The finding that better delayed memory predicted more severe AVH is consistent with AVH memory models suggesting that AVH are dependent upon information recalled from memory storage.
Functional MRI studies have identified a distributed set of brain activations to be associated with auditory verbal hallucinations (AVH). However, very little is known about how activated brain ...regions may be linked together into AVH-generating networks. Fifteen volunteers with schizophrenia or schizoaffective disorder pressed buttons to indicate onset and offset of AVH during fMRI scanning. When a general linear model was used to compare blood oxygenation level dependence signals during periods in which subjects indicated that they were versus were not experiencing AVH ("AVH-on" versus "AVH-off"), it revealed AVH-related activity in bilateral inferior frontal and superior temporal regions; the right middle temporal gyrus; and the left insula, supramarginal gyrus, inferior parietal lobule, and extranuclear white matter. In an effort to identify AVH-related networks, the raw data were also processed using independent component analyses (ICAs). Four ICA components were spatially consistent with an a priori network framework based upon published meta-analyses of imaging correlates of AVH. Of these four components, only a network involving bilateral auditory cortices and posterior receptive language areas was significantly and positively correlated to the pattern of AVH-on versus AVH-off. The ICA also identified two additional networks (occipital-temporal and medial prefrontal), not fully matching the meta-analysis framework, but nevertheless containing nodes reported as active in some studies of AVH. Both networks showed significant AVH-related profiles, but both were most active during AVH-off periods. Overall, the data suggest that AVH generation requires specific and selective activation of auditory cortical and posterior language regions, perhaps coupled to a release of indirect influence by occipital and medial frontal structures.
Using a case study research design, this study investigated the kind of mentoring three secondary social studies preservice teachers received during their 15-week student teaching semester. They were ...selected for this study because each had been placed with a cooperating teacher who was recommended by university clinical faculty and a university student teaching consultant as being an outstanding mentor. This study specifically sought to discover what elements of preservice mentoring emerged as well as identify those elements that seemed to contribute most to the development of the cooperating teacher/student teacher relationship. Data was collected using observations, field notes, interviews, in-class conversations with the cooperating teachers, preservice teachers journaling, and document review. The data I gathered allowed me to describe: (1) How each cooperating teacher conducted the student teaching semester. (2) What the cooperating teachers' beliefs were about student teachers and the student teaching experience. (3) The elements of preservice mentoring emerged during the semester. (4) What the preservice teachers identified as the key elements that contributed the most to the development of the relationship with their cooperating teacher. The cooperating teachers were observed engaging in the following mentoring activities with their preservice teachers: acting as a colleague, caring, coaching, guiding, listening and questioning, looking on and encouraging rather than taking over and doing the work, providing status in the classroom, and serving as a positive role model. Of these, the preservice teachers in this study identified status and added freedom as the two key elements that seemed to contributed the most to the development of the preservice teacher/cooperating teacher relationship. The insights gleaned from the three cooperating teachers in this study could inform the future work of college and university teacher education programs as well as those who will be selecting cooperating teachers.
A preferences scale based on four types of learning preferences was employed to determine which preference would be indicated most frequently by a selected group of Native American adolescents. The ...pattern-symbols preference was selected by the majority. When the group was divided by sex, it showed the females were more evenly divided in their learning preference than the males. Suggestions are made for teaching activities which would be compatible with the preferences indicated by the majority of males. The key factors indicated where a preference for smallgroup activities that allow for personal interpretation of the subject in a cooperative rather than competitive learning environment.
The perspectives of people who use drugs are critical in understanding why people choose to reduce harm in relation to drug use, what practices are considered or preferred in conceptualizations of ...harm reduction, and which environmental factors interfere with or support the use of harm reduction strategies. This study explores how people who inject drugs (PWID) think about harm reduction and considers the critical imperative of equity in health and social services delivery for this community.
This community-based participatory research study was conducted in a Canadian urban centre. Using a peer-based recruitment and interviewing strategy, semi-structured qualitative interviews were conducted by and with PWID. The Vidaview Life Story Board, an innovative tool where interviewers and participant co-construct a visual "life-scape" using a board, markers, and customized picture magnets, was used to facilitate the interviews. The topics explored included injection drug use and harm reduction histories, facilitators and barriers to using harm reduction strategies, and suggestions for improving services and supports.
Twenty-three interviews with PWID (14 men and 9 women) were analysed, with a median age of 50. Results highlighted an expanded conceptualization of harm reduction from the perspectives of PWID, including motivations for adopting harm reduction strategies and a description of harm reduction practices that went beyond conventional health-focused concerns. The most common personal practices that PWID used included working toward moderation, employing various cognitive strategies, and engaging in community activities. The importance of social or peer support and improving self-efficacy was also evident. Further, there was a call for less rigid eligibility criteria and procedures in health and social services, and the need to more adequately address the stigmatization of drug users.
These findings demonstrated that PWID incorporate many personal harm reduction practices in their daily lives to improve their well-being, and these practices highlight the importance of agency, self-care, and community building. Health and social services are needed to better support these practices because the many socio-structural barriers this community faces often interfere with harm reduction efforts. Finally, "one size does not fit all" when it comes to harm reduction, and more personalized or de-medicalized conceptualizations are recommended.
Dyes with nonlinear optical (NLO) properties enable new imaging techniques and photonic systems. We have developed a dye (DANPY-1) for photonics applications in biological substrates such as nucleic ...acids; however, the design specification also enables it to be used for visualizing biomolecules. It is a prototype dye demonstrating a water-soluble, NLO-active fluorophore with high photostability, a large Stokes shift, and a favorable toxicity profile. A practical and scalable synthetic route to DANPY salts has been optimized featuring: (1) convergent Pd-catalyzed Suzuki coupling with pyridine 4-boronic acid, (2) site-selective pyridyl N-methylation, and (3) direct recovery of crystalline intermediates without chromatography. We characterize the optical properties, biocompatibility, and biological staining behavior of DANPY-1. In addition to stability and solubility across a range of polar media, the DANPY-1 chromophore shows a first hyperpolarizability similar to common NLO dyes such as Disperse Red 1 and DAST, a large two-photon absorption cross section for its size, substantial affinity to nucleic acids in vitro, an ability to stain a variety of cellular components, and strong sensitivity of its fluorescence properties to its dielectric environment.
Fatty acid analysis is essential to a broad range of applications including those associated with the nascent algal biofuel and algal bioproduct industries. Current fatty acid profiling methods ...require lengthy, sequential extraction and transesterification steps necessitating significant quantities of analyte. We report the development of a rapid, microscale, single-step, in situ protocol for GC–MS lipid analysis that requires only 250 μg dry mass per sample. We furthermore demonstrate the broad applications of this technique by profiling the fatty acids of several algal species, small aquatic organisms, insects and terrestrial plant material. When combined with fluorescent techniques utilizing the BODIPY dye family and flow cytometry, this micro-assay serves as a powerful tool for analyzing fatty acids in laboratory and field collected samples, for high-throughput screening, and for crop assessment. Additionally, the high sensitivity of the technique allows for population analyses across a wide variety of taxa.
The production of algal-derived oil has been recognized as an expanding new industry. Algal oil recovery and quality are impacted by both biological (algal cell type, growth physiology) and technical ...(recovery and extraction methodologies) constraints. Unfortunately, and unlike other well-established food and oil commodities, presently no universal reference standard exists for use in the algal oil industry.
A laboratory-optimized strain of Chrysochromulina sp. is proposed as a natural matrix reference standard for algal fatty acid analysis. The alga is amenable to this purpose because: (a) as a soft-bodied organism, it is susceptible to many disruption and fatty acid extraction techniques; (b) it has a high fatty acid content (~40% dry weight); (c) the growth response and lipid profiles of this organism are highly reproducible; (d) unlike many algae that have limited fatty acid distributions, Chrysochromulina sp. cells contain a broad representation of both saturated and unsaturated fatty acids ranging from C:14 to C:22. As a proof of concept, Chrysochromulina sp. was used as a reference standard for comparing 20 taxonomically diverse algal cultures, grown under identical physiological conditions and analyzed for fatty acid content using a micro-GC/MS analytical technique.
Expanding efforts in both commercial and research facilities will require the screening and monitoring of candidate algal strains for lipid synthesis. Universal adoption of a reference standard will provide a common platform to compare the fatty acid compositions of different algal strains grown under diverse environmental conditions and subjected to different oil recovery methods. A reproducibly generated natural matrix standard will have two distinct advantages: (a) as a reproducibly generated standard, it can supplant reference products that vary markedly among suppliers; and (b) the use of a natural matrix standard will help in the identification and elimination of errors in lipid extraction, derivatization and analysis.
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