129 research outputs found
Performance improvement technology for building a sustainable OER initiative in an academic library
In keeping with its land grant mission, a university campus library partnered with several OER advocacy efforts on both national and state levels to promote the creation and use of OER at the university. While the program had some initial success in inspiring faculty to create and use OER in their courses, the effort proved difficult to sustain. This paper presents the application of the Performance Improvement/HPT model to an Open Educational Resources (OER) initiative in a university library. This paper focuses specifically on three phases of the process: organizational analysis, environmental analysis, and gap analysis We share results of that application and discuss how the HPT model might effectively be applied to other similar programs.Peer reviewedLibraryEducational Technolog
Supported phospholipid membranes as biometric labs-on-a-chip: analytical devices that mimic cell membrane architectures and provide insight into the mechanism of biopreservation
This dissertation focuses on the applications of solid supported phospholipid
membranes as mimics of the cellular membrane using lab-on-a-chip devices in order to
study biochemical events such as ligand-receptor binding and the chemical mechanism
for the preservation of the biomembrane. Supported lipid bilayers (SLBs) mimic the
native membrane by presenting the important property of two-dimensional lateral
fluidity of the individual lipid molecules within the membrane. This is the same
property that allows for the reorganization of native membrane components and
facilitates multivalent ligand-receptor interactions akin to immune response, cell
signaling, pathogen attack and other biochemical processes.
The study is divided into two main facets. The first deals with developing a
novel lipopolymer supported membrane biochip consisting of Poly(ethylene glycol)
(PEG)-lipopolymer incorporated membranes. The formation and characterization of the
lipopolymer membranes was investigated in terms of the polymer size, concentration
and molecular conformation. The lateral diffusion of the PEG-bilayers was similar to
the control bilayers. The air-stability conferred to SLBs was determined to be more effective when the PEG polymer was at, or above, the onset of the mushroom-to-brush
transition. The system is able to function even after dehydration for 24 hours. Ligandreceptor
binding was analyzed as a function of PEG density. The PEG-lipopolymer acts
as a size exclusion barrier for protein analytes in which the binding of streptavidin was
unaffected whereas the binding of the much larger IgG and IgM were either partially or
completely inhibited in the presence of PEG.
The second area of this study presents a molecular mechanism for in vivo
biopreservation by employing solid supported membranes as a model system. The
molecular mechanism of how a variety of organisms are preserved during stresses such
as anhydrobiosis or cryogenic conditions was investigated. We investigated the
interaction of two disaccharides, trehalose and maltose with the SLBs. Trehalose was
found to be the most effective in preserving the membrane, whereas maltose exhibited
limited protection. Trehalose lowers the lipid phase transition temperature and
spectroscopic evidence shows the intercalation of trehalose within the membrane
provides the chemical and morphological stability under a stress environment
Recommended from our members
Escape of DNA from a Weakly Biased Thin Nanopore: Experimental Evidence for a Universal Diffusive Behavior
We report experimental escape time distributions of double-stranded DNA molecules initially threaded halfway through a thin solid-state nanopore. We find a universal behavior of the escape time distributions consistent with a one-dimensional first passage formulation notwithstanding the geometry of the experiment and the potential role of complex molecule-liquid-pore interactions. Diffusion constants that depend on the molecule length and pore size are determined. Also discussed are the practical implications of long time diffusive molecule trapping in the nanopore.Engineering and Applied SciencesPhysic
Exploring preservice teachers' technology integration repertoire: A mixed methods study
The purpose of this convergent mixed methods study was to explore how an undergraduate educational technology course impacts preservice teachers' TPACK knowledge and how it affects the development of their technology integration repertoire. A total of 14 preservice teachers enrolled in a face-to-face section of an educational technology course in Fall 2021 participated in the study. Quantitative findings indicate the growth of participants' TPACK (self-perceptions and application) over the course of the semester. The qualitative findings suggest that the technology integration repertoire of the participants developed from a tool-based approach to the learner first and then the tool approach that confirms the growth of the TPK. This study is significant to teacher educators by providing an overview of the preservice teachers' decision-making process for using technologies in their lesson plans and their overall growth in technology integration during an educational technology course. The findings of this study could inform teacher preparation programs about the instructional activities that are the most beneficial for preservice teachers to experience for TPACK development
Recommended from our members
Base Dependent DNA-carbon Nanotube Interactions: Activation Enthalpies and Assembly-disassembly Control
We quantify the base dependent interactions between single stranded DNA and single walled carbon nanotubes (SWNTs) in solution. DNA/SWNT hybrids hold the promise of applications ranging from nanoscale electronics and assembly of nanotube based materials, to drug delivery and DNA sequencing. These applications require control over the hybrid assembly and disassembly. Our analytical assay reveals the order of nucleobase binding strengths with SWNTs as G>C>A>T. Furthermore, time dependent fixed temperature experiments that probe the kinetics of the dissociation process provide values for the equilibrium constants and dissociation enthalpies that underlie the microscopic interactions. Quantifying the base dependency of hybrid stability shows how insight into the energetics of the component interactions facilitates control over hybrid assembly and disassembly.Engineering and Applied SciencesMolecular and Cellular BiologyPhysic
Measurement invariance testing of the patient health questionnaire-9 (PHQ-9) across people with and without diabetes mellitus from the NHANES, EHMS and UK Biobank datasets
Background: The prevalence of depression is higher among those with diabetes than in the general population. The Patient Health Questionnaire (PHQ-9) is commonly used to assess depression in people with diabetes, but measurement invariance of the PHQ-9 across groups of people with and without diabetes has not yet been investigated.
Methods: Data from three independent cohorts from the USA (n=1,886 with diabetes, n=4,153 without diabetes), Quebec, Canada (n= 800 with diabetes, n= 2,411 without diabetes), and the UK (n=4,981 with diabetes, n=145,570 without diabetes), were used to examine measurement invariance between adults with and without diabetes. A series of multiple group confirmatory factor analyses were performed, with increasingly stringent model constraints applied to assess configural, equal thresholds, and equal thresholds and loadings invariance, respectively. One-factor and two-factor (somatic and cognitive-affective items) models were examined.
Results: Results demonstrated that the most stringent models, testing equal loadings and thresholds, had satisfactory model fit in the three cohorts for one-factor models (RMSEA = .063 or below and CFI = .978 or above) and two-factor models (RMSEA = .042 or below and CFI = .989 or above).
Limitations: Data were from Western countries only and we could not distinguish between type of diabetes.
Conclusions: Results provide support for measurement invariance between groups of people with and without diabetes, using either a one-factor or a two-factor model. While the two-factor solution has a slightly better fit, the one-factor solution is more parsimonious. Depending on research or clinical needs, both factor structures can be used
Roles de las tecnologías emergentes en el manejo de información de desastres naturales
Editorial: Roles de las tecnologías emergentes en el manejo de información de desastres naturale
The bidirectional longitudinal association between depressive symptoms and HbA 1c : a systematic review and meta‐analysis
Aim
To investigate whether there is a bidirectional longitudinal association of depression with HbA1c.
Methods
We conducted a systematic literature search in PubMed, PsycINFO, CINAHL and EMBASE for observational, longitudinal studies published from January 2000 to September 2020, assessing the association between depression and HbA1c in adults. We assessed study quality with the Newcastle-Ottawa-Scale. Pooled effect estimates were reported as partial correlation coefficients (rp) or odds ratios (OR).
Results
We retrieved 1,642 studies; 26 studies were included in the systematic review and eleven in the meta-analysis. Most studies (16/26) focused on type 2 diabetes. Study quality was rated as good (n=19), fair (n=2) and poor (n=5). Of the meta-analysed studies, six investigated the longitudinal association between self-reported depressive symptoms and HbA1c and five the reverse longitudinal association, with a combined sample size of n=48,793 and a mean follow-up of 2 years. Higher levels of baseline depressive symptoms were associated with subsequent higher levels of HbA1c (partial r=0.07;[95%CI0.03,0.12]; I238%). Higher baseline HbA1c values were also associated with 18% increased risk of (probable) depression (OR=1.18;[95%CI1.12,1.25]; I20.0%).
Conclusions
Our findings support a bidirectional longitudinal association between depressive symptoms and HbA1c. However, the observed effect sizes were small and future research in large-scale longitudinal studies is needed to confirm this association. Future studies should investigate the role of type of diabetes and depression, diabetes distress and diabetes self-management behaviours. Our results may have clinical implications, as depressive symptoms and HbA1c levels could be targeted concurrently in the prevention and treatment of diabetes and depression
Nanostructures from self-assembling triazine tertiary amine N-oxide amphiphiles
A new set of amphiphilic tertiary amine N-oxides has been prepared and their self-assembly properties observed in aqueous solution by tensiometry, dynamic and static light scattering. X-ray crystallographic analysis of parent amines and sulfoxide congeners indicates the formation of hydrogen bonded dimers as the primary assembly unit for formation of vesicles in preference to the compact micelles typical of lauryl dimethylamine N-oxide (LDAO). 6-Benzyloxy-N,N'-bis(5-diethylaminopentylamine oxide)[1,3,5]triazine-2,4-diamine forms a 1 μm vesicle observed to entrap fluorescein. The [1,3,5]triazine core thus allows variation of the new self-assembled structures from nano- to micrometre length scales
- …