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Variation in early life maternal care predicts later long range frontal cortex synapse development in mice.
Empirical and theoretical work suggests that early postnatal experience may inform later developing synaptic connectivity to adapt the brain to its environment. We hypothesized that early maternal experience may program the development of synaptic density on long range frontal cortex projections. To test this idea, we used maternal separation (MS) to generate environmental variability and examined how MS affected 1) maternal care and 2) synapse density on virally-labeled long range axons of offspring reared in MS or control conditions. We found that MS and variation in maternal care predicted bouton density on dorsal frontal cortex axons that terminated in the basolateral amygdala (BLA) and dorsomedial striatum (DMS) with more, fragmented care associated with higher density. The effects of maternal care on these distinct axonal projections of the frontal cortex were manifest at different ages. Maternal care measures were correlated with frontal cortex → BLA bouton density at mid-adolescence postnatal (P) day 35 and frontal cortex → DMS bouton density in adulthood (P85). Meanwhile, we found no evidence that MS or maternal care affected bouton density on ascending orbitofrontal cortex (OFC) or BLA axons that terminated in the dorsal frontal cortices. Our data show that variation in early experience can alter development in a circuit-specific and age-dependent manner that may be relevant to understanding the effects of early life adversity
Identifying Essential Competency Areas for Occupational Therapy Education: A Scoping Review
This scoping review aims to explore the essential areas of competency in occupational therapy as the ability to acquire the necessary knowledge, skills, and values for the profession is not easily quantifiable. The objectives of this study were two-fold: (1) identify the key competency areas of occupational therapy and (2) identify assessments that measure the competency areas. The review was conducted by a team of a librarian and two independent reviewers to systematically search the peer-reviewed literature. The search yielded 296 articles and 52 articles that met the inclusion criteria. These articles were categorized under four overarching themes: (1) professional attitudes that include cultural competence and the ability to uphold ethical and legal responsibilities; (2) professional communication such as engaging in active participation with the client; (3) ability to work in collaboration with inter- and intra- professionals; and (4) provide quality service with a focus on evidence-based practices. Additional research is warranted to further build the evidence base of occupational therapy competence to improve outcomes for patients. The results of this study contribute to the ongoing collective work of researchers and practitioners who wish to continually improve a client-centered holistic approach through the recognition of these key themes. Identifying the relevant measures that assess these themes establishes the foundation needed to support the continuous effort to educate and support entry-level occupational therapists by paving the way for further development and refinement of measurement tools
Communication brève sur les perceptions et les comportements postulants potentiels aux études de médecine par rapport à la recherche en lien avec l’admission dans une faculté de médecine canadienne
Background: Aspiring medical students behave based on their perception of what is valued in the selection process. While research experience is not explicitly considered in most Canadian admissions policies, it is commonly held as valuable within aspiring medical student communities. The purpose of this study is to describe the perceptions and behaviours of aspiring medical students with respect to gaining research experience in support of their medical school applications.
Methods: We surveyed prospective applicants of Canadian medical schools between August 2021 and November 2021, then compiled descriptive statistics pertaining to their perceptions and behaviours.
Results: Respondents affirmed the belief that research experience is valued in medical school admissions processes. They reported spending approximately 13 hours per week engaged in research, which usually did not yield publication or presentation recognition.
Conclusion: Aspiring medical students invest substantial time and energy in research experiences to benefit their applications. There is room for medical schools to be more transparent about the value of research experience in their admissions processes.Contexte : Le comportement des candidats aux études de médecine est déterminé par leur perception de ce qui est valorisé dans le processus de sélection. Tandis que la plupart des établissements canadiens ne mentionnent pas explicitement l’expérience en recherche comme prérequis d’admission, les futurs candidats, eux, voient une telle expérience comme un atout précieux. L’objectif de cette étude est de décrire les perceptions et les comportements des futurs étudiants en médecine par rapport à l’acquisition d’une expérience en recherche en appui à leur demande d’admission dans une école de médecine.
Méthodes : Nous avons interrogé des postulants potentiels aux programmes de médecine au Canada entre août 2021 et novembre 2021, et nous avons compilé des statistiques descriptives relatives à leurs perceptions et à leurs comportements.
Résultats : Les répondants ont affirmé croire que l’expérience en recherche est valorisée dans les processus d’admission aux facultés de médecine. Ils ont déclaré consacrer environ 13 heures par semaine à la recherche, qui, le plus souvent, n’a pas mené à des publications ou des présentations.
Conclusion : Les futurs candidats aux études de médecine investissent beaucoup de temps et d’énergie dans des activités de recherche afin d’améliorer leur dossier de candidature. Les facultés de médecine devraient se prononcer de manière transparente sur l’importance attribuée à l’expérience en recherche dans le cadre de leur processus d’admission
Study of T cell activation and migration at the single-cell and single-molecule level
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2011.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Cataloged from PDF version of thesis.Includes bibliographical references (p. 167-184).T cells are required by their immunological roles to recirculate in the body and migrate to tissue sites, a journey that exposes them to distorting forces and physical obstacles that hinder their movement. Therefore, they must possess appropriate deformability to accommodate and adapt to these mechanical stimuli to migrate unimpeded. Since T cells alter their physical properties and migration routes upon activation, they may possess dissimilar mechanical properties as a result of this process. This hypothesis was tested using the techniques micropipette aspiration and atomic force microscopy, which allow the investigation of the elastic and viscous responses of single T cells. It was discovered that the activation process reduced T cell stiffness by more than three folds, a finding that agrees with the motility gain observed in activated T cells. The same testing procedure was applied to Wiskott-Aldrich syndrome protein (WASp)-deficient T cells that exhibit abnormal morphology and impaired chemotaxis. The stiffness of the diseased cells in the naive state was 1.5 times less than that of the non-diseased cells, a result that may be due to the disrupted polymerization and cross-linking of the actin cytoskeleton in the absence of WASp, a regulator of actin growth and organization. Furthermore, the viscous response of the diseased cells in the activated state was found to be impaired. Chemokines were found to dramatically reduce the stiffness of naive T cells that were induced to migrate. These findings suggest that WASp plays an important role in maintaining cell mechanical property and facilitating T cell extravasation by tailoring the cells' deformability. At the molecular level, activation of T cells is triggered by the binding of their surface receptors to antigens, a mechanism that is also key in T cell development. In both cases, the bond strength, conventionally measured by the affinity (KD) or the dissociation rate (koff) of the interacting pair, dictates the biological outcome. Since a few weak interactions may nudge a sub-threshold signal over the threshold strength, and observing that the current methods for measuring KD and koff lack the resolution to detect very weak bonds, this work explored the possibility of utilizing dynamic force spectroscopy (DFS) to study very weak binding strengths. Preliminary results confirm this capability.by Irene Yin-Ting Chang.Ph.D
Continuum elasticity theory of edge excitations in a two-dimensional electron liquid with finite range interactions
We make use of continuum elasticity theory to investigate the collective
modes that propagate along the edge of a two-dimensional electron liquid or
crystal in a magnetic field. An exact solution of the equations of motion is
obtained with the following simplifying assumptions: (i) The system is {\it
macroscopically} homogeneous and isotropic in the half-plane delimited by the
edge (ii) The electron-electron interaction is of finite range due to screening
by external electrodes (iii) The system is nearly incompressible. At
sufficiently small wave vector we find a universal dispersion curve independent of the shear modulus. At larger wave vectors the dispersion
can change its form in a manner dependent on the comparison of various length
scales. We obtain analytical formulas for the dispersion and damping of the
modes in various physical regimes.Comment: 3 figure
Exploring the functional space of thiiranes as gelatinase inhibitors using click chemistry
A series of 4-[(triazolyl)methoxy]phenyl analogs of the phenoxyphenyl-substituted thiirane SB-3CT 1 was evaluated for its ability to inhibit gelatinases, members of the matrix metalloproteinase family of enzymes. The triazole segment of these inhibitors was assembled using the Meldal-Sharpless copper-catalyzed Huisgen dipolar cycloaddition of an azide and a terminal alkyne. While these triazole derivatives possessed fair activity as gelatinase inhibitors, an intermediate used in the dipolar cycloaddition, 4-(propargyloxy)phenyl derivative 2, showed very good activity (<50% inhibitory activity following a 3 h pre-incubation of 2 at a concentration of 3 μM) as an inhibitor of human matrix metalloproteinase-2.Fil: Testero, Sebastian Andres. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - Rosario. Instituto de QuÃmica Rosario. Universidad Nacional de Rosario. Facultad de Ciencias BioquÃmicas y Farmacéuticas. Instituto de QuÃmica Rosario; ArgentinaFil: Llarrull, Leticia Irene. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - Rosario. Instituto de BiologÃa Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias BioquÃmicas y Farmacéuticas. Instituto de BiologÃa Molecular y Celular de Rosario; ArgentinaFil: Fisher, Jed F.. University of Notre Dame; Estados UnidosFil: Chang, Mayland. University of Notre Dame; Estados UnidosFil: Mobashery, Shahriar. University of Notre Dame; Estados Unido
Streptococcus pneumoniae in Urinary Tracts of Children with Chronic Kidney Disease
Streptococcus pneumoniae is not commonly considered an agent of urinary tract infections. We report 3 children with urinary tract abnormalities who had high numbers of S. pneumoniae in their urine (>104 CFU/mL) and varying clinical symptoms
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