223 research outputs found

    Trends in Expenses and Revenues at Not-for-profit and For-profit Postsecondary Institutions: The Nondistribution Constraint and the Future of the Trust Market

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    In the United States, every child has the right to an education and is required by law to attend school. The government provides an enormous number of public schools throughout the country, free of charge, in order to ensure education for all, yet there are families who choose to homeschool their children instead. Hill (2010) explains that “homeschooling is not a new phenomenon. In colonial days families, including wealthy ones, educated their children at home, combining the efforts of parents, tutors, and older children” (p.1). He goes on to mention how colonial rural one-room schoolhouses provided a place for the children of several families to study together under the direction of a teacher who implemented their personal program of instruction

    A Quantitative Analysis of the Relationship among Sources of Aid and Predictors of Student Veteran Graduation and Persistence

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    This study uses multinomial logistic regression models to identify significant predictors of graduation and persistence for veteran and military-aligned students (n=1141) at one veteran-friendly, not-for-profit institution.  Several statistically significant predictors of graduation and persistence for veteran and military-aligned students are unique when compared to the literature on the general student population, such as the positive effect of part time enrollment and the negative effect of continuous enrollment.  In addition, comparisons are made among subgroups of the students based on the source of their financial aid (government, institutional, no veteran or military aid).  Distinct policies designed to assist veteran and military-aligned students are suggested as well as individual policies to support subgroups of these students.  Unique institutional policies that may have a positive impact on the subgroups of students include encouragement for part time enrollment for veteran and military-aligned students who are not using government funded veteran and military aid and assistance with stop outs and returns for those using government funded veteran and military aid.  Federal policy implications such as the impact of the 36 month limit on Post-9/11 GI Bill funding are discussed. </p

    Analysis of the human cytomegalovirus genomic region from UL146 through UL147A reveals sequence hypervariability, genotypic stability, and overlapping transcripts

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    BACKGROUND: Although the sequence of the human cytomegalovirus (HCMV) genome is generally conserved among unrelated clinical strains, some open reading frames (ORFs) are highly variable. UL146 and UL147, which encode CXC chemokine homologues are among these variable ORFs. RESULTS: The region of the HCMV genome from UL146 through UL147A was analyzed in clinical strains for sequence variability, genotypic stability, and transcriptional expression. The UL146 sequences in clinical strains from two geographically distant sites were assigned to 12 sequence groups that differ by over 60% at the amino acid level. The same groups were generated by sequences from the UL146-UL147 intergenic region and the UL147 ORF. In contrast to the high level of sequence variability among unrelated clinical strains, the sequences of UL146 through UL147A from isolates of the same strain were highly stable after repeated passage both in vitro and in vivo. Riboprobes homologous to these ORFs detected multiple overlapping transcripts differing in temporal expression. UL146 sequences are present only on the largest transcript, which also contains all of the downstream ORFs including UL148 and UL132. The sizes and hybridization patterns of the transcripts are consistent with a common 3'-terminus downstream of the UL132 ORF. Early-late expression of the transcripts associated with UL146 and UL147 is compatible with the potential role of CXC chemokines in pathogenesis associated with viral replication. CONCLUSION: Clinical isolates from two different geographic sites cluster in the same groups based on the hypervariability of the UL146, UL147, or the intergenic sequences, which provides strong evidence for linkage and no evidence for interstrain recombination within this region. The sequence of individual strains was absolutely stable in vitro and in vivo, which indicates that sequence drift is not a mechanism for the observed sequence hypervariability. There is also no evidence of transcriptional splicing, although multiple overlapping transcripts extending into the adjacent UL148 and UL132 open reading frames were detected using gene-specific probes

    Emergent complex neural dynamics

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    A large repertoire of spatiotemporal activity patterns in the brain is the basis for adaptive behaviour. Understanding the mechanism by which the brain's hundred billion neurons and hundred trillion synapses manage to produce such a range of cortical configurations in a flexible manner remains a fundamental problem in neuroscience. One plausible solution is the involvement of universal mechanisms of emergent complex phenomena evident in dynamical systems poised near a critical point of a second-order phase transition. We review recent theoretical and empirical results supporting the notion that the brain is naturally poised near criticality, as well as its implications for better understanding of the brain

    The Default Mode Network Mediates the Impact of Infant Regulatory Problems on Adult Avoidant Personality Traits

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    Background Infant regulatory problems (RPs), i.e. problems with crying, feeding, and/or sleeping, are associated with behavioral and emotional problems in childhood. It is unclear, however, whether these behavioral and emotional problems persist into adulthood. The default mode (DMN) and salience networks (SN) support both interoceptive regulation and social/emotional abilities. We thus hypothesized that adults with infant RPs have more behavioral and emotional problems, mediated by DMN/SN alterations. Methods Within the scope of the Bavarian Longitudinal Study, adults (mean age 28 years; 50% females) with (N = 79) and without (N = 254) a history of multiple and/or persistent infant RPs were assessed by the Young Adult Self Report (YASR) to measure behavioral and emotional problems, and – in a sub-sample (N = 49 and N = 71) – by resting-state functional magnetic resonance imaging (rs-fMRI) to measure DMN/SN integrity via intrinsic functional connectivity (iFC). Results Compared to adults without infant RPs, adults with infant RPs had more total problems (p=0.002), internalizing problems (p = 0.005), and more avoidant personality traits (p < 0.001). They showed decreased iFC of the DMN and SN. DMN iFC-decreases were strongest in adults with multiple and persistent RPs and linked with avoidant personality traits (r = - 0.42, p = 0.006). Remarkably, DMN iFC-decrements fully mediated the association between infant RPs and adult avoidant personality traits. Conclusions Adults with infant RPs have more avoidant personality traits that are mediated by the DMN. Persistent/multiple infant RPs and the DMN may be targets to attenuate behavioral and emotional problems

    Resting state functional connectivity of the whole head with near-infrared spectroscopy

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    Resting state connectivity aims to identify spontaneous cerebral hemodynamic fluctuations that reflect neuronal activity at rest. In this study, we investigated the spatial-temporal correlation of hemoglobin concentration signals over the whole head during the resting state. By choosing a source-detector pair as a seed, we calculated the correlation value between its time course and the time course of all other source-detector combinations, and projected them onto a topographic map. In all subjects, we found robust spatial interactions in agreement with previous fMRI and NIRS findings. Strong correlations between the two opposite hemispheres were seen for both sensorimotor and visual cortices. Correlations in the prefrontal cortex were more heterogeneous and dependent on the hemodynamic contrast. HbT provided robust, well defined maps, suggesting that this contrast may be used to better localize functional connectivity. The effects of global systemic physiology were also investigated, particularly low frequency blood pressure oscillations which give rise to broad regions of high correlation and mislead interpretation of the results. These results confirm the feasibility of using functional connectivity with optical methods during the resting state, and validate its use to investigate cortical interactions across the whole head

    Auditory network connectivity in tinnitus patients: a resting-state fMRI study

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    Objective: Resting-state functional magnetic resonance imaging (fMRI) uncovers correlated activity between spatially distinct functionally related brain regions and offers clues about the integrity of functional brain circuits in people with chronic subjective tinnitus. We chose to investigate auditory network connectivity, adopting and extending previously used analyses methods to provide an independent evaluation of replicability. Design: Independent components analysis (ICA) was used to identify coherent patterns arising from spontaneous brain signals within the resting-state data. The auditory network component was extracted and evaluated. Bivariate and partial correlation analyses were performed on pre-defined regions of bilateral auditory cortex to assess functional connectivity. Study sample: Our design carefully matched participant groups for possible confounds, such as hearing status. Twelve patients (seven male, five female; mean age 66 years) all with chronic constant tinnitus and eleven controls (eight male, three female; mean age 68 years) took part. Results: No significant differences were found in auditory network connectivity between groups after correcting for multiple statistical comparisons in the analysis. This contradicts previous findings reporting reduced auditory network connectivity; albeit at a less stringent statistical threshold. Conclusions: Auditory network connectivity does not appear to be reliably altered by the experience of chronic subjective tinnitus

    Spontaneous Brain Activity in the Default Mode Network Is Sensitive to Different Resting-State Conditions with Limited Cognitive Load

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    BACKGROUND: Recent functional MRI (fMRI) studies have demonstrated that there is an intrinsically organized default mode network (DMN) in the resting brain, primarily made up of the posterior cingulate cortex (PCC) and the medial prefrontal cortex (MPFC). Several previous studies have found that the DMN is minimally disturbed during different resting-state conditions with limited cognitive demand. However, this conclusion was drawn from the visual inspection of the functional connectivity patterns within the DMN and no statistical comparison was performed. METHODOLOGY/PRINCIPAL FINDINGS: Four resting-state fMRI sessions were acquired: 1) eyes-closed (EC) (used to generate the DMN mask); 2) EC; 3) eyes-open with no fixation (EO); and 4) eyes-open with a fixation (EO-F). The 2-4 sessions were counterbalanced across participants (n = 20, 10 males). We examined the statistical differences in both functional connectivity and regional amplitude of low frequency fluctuation (ALFF) within the DMN among the 2-4 resting-state conditions (i.e., EC, EO, and EO-F). Although the connectivity patterns of the DMN were visually similar across these three different conditions, we observed significantly higher functional connectivity and ALFF in both the EO and the EO-F conditions as compared to the EC condition. In addition, the first and second resting EC conditions showed significant differences within the DMN, suggesting an order effect on the DMN activity. CONCLUSIONS/SIGNIFICANCE: Our findings of the higher DMN connectivity and regional spontaneous activities in the resting state with the eyes open suggest that the participants might have more non-specific or non-goal-directed visual information gathering and evaluation, and mind wandering or daydreaming during the resting state with the eyes open as compared to that with the eyes closed, thus providing insights into the understanding of unconstrained mental activity within the DMN. Our results also suggest that it should be cautious when choosing the type of a resting condition and designating the order of the resting condition in multiple scanning sessions in experimental design

    Disrupted Functional Brain Connectivity in Partial Epilepsy: A Resting-State fMRI Study

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    Examining the spontaneous activity to understand the neural mechanism of brain disorder is a focus in recent resting-state fMRI. In the current study, to investigate the alteration of brain functional connectivity in partial epilepsy in a systematical way, two levels of analyses (functional connectivity analysis within resting state networks (RSNs) and functional network connectivity (FNC) analysis) were carried out on resting-state fMRI data acquired from the 30 participants including 14 healthy controls(HC) and 16 partial epilepsy patients. According to the etiology, all patients are subdivided into temporal lobe epilepsy group (TLE, included 7 patients) and mixed partial epilepsy group (MPE, 9 patients). Using group independent component analysis, eight RSNs were identified, and selected to evaluate functional connectivity and FNC between groups. Compared with the controls, decreased functional connectivity within all RSNs was found in both TLE and MPE. However, dissociating patterns were observed within the 8 RSNs between two patient groups, i.e, compared with TLE, we found decreased functional connectivity in 5 RSNs increased functional connectivity in 1 RSN, and no difference in the other 2 RSNs in MPE. Furthermore, the hierarchical disconnections of FNC was found in two patient groups, in which the intra-system connections were preserved for all three subsystems while the lost connections were confined to intersystem connections in patients with partial epilepsy. These findings may suggest that decreased resting state functional connectivity and disconnection of FNC are two remarkable characteristics of partial epilepsy. The selective impairment of FNC implicated that it is unsuitable to understand the partial epilepsy only from global or local perspective. We presumed that studying epilepsy in the multi-perspective based on RSNs may be a valuable means to assess the functional changes corresponding to specific RSN and may contribute to the understanding of the neuro-pathophysiological mechanism of epilepsy
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