133 research outputs found

    Why Are Students Doing Research? Examining The Motivation Of Students Involved In Undergraduate Research Programs

    Get PDF
    Use of self-determination theory (SDT) within the science classroom focuses primarily on ways to integrate intrinsic motivation into students\u27 identity. Experiential learning plays a large role in promoting learning by shaping students\u27 interests, identity, and intrinsic aspirations. This phenomenological research study sought to understand how experiential learning experiences helped influence career aspirations of graduate students within ecological disciplines. By determining how their experiences met three basic psychological needs outlined by SDT (competence, autonomy, and relatedness), we were able to examine which regulators drove motivation. In the qualitative pilot study, participants developed a genuine enjoyment and appreciation for their discipline as they began engaging in more complex research. As interest grew, so did levels of competence and autonomy. Students were able to apply their experiences in novel ways which enabled them to see the connectivity of their discipline and develop internal aspirations for science. In addition to aspirations supported by experiential learning opportunities, mentorship, family/cultural support, and the desire for a work-life balance further shaped their career aspirations and satisfied the basic need for relatedness. This boost of confidence and sense of belonging helped participants shed doubts and other external pressures that allowed students to believe that they might not belong in science. Finding from this pilot study helped inform the development of a larger quantitative survey. The Biological Research Experience Survey (BRES) sought to understand how the basic psychological needs of self-determination theory are being satisfied during undergraduate research experience. Using a numerous previously validated instruments from the SDT and science education literature, the BRES connected a number of underlying constructs through exploratory factor analysis. Five factors emerged, accounting for 62.19% of the variance, and were named Scientific Identity, Mentor Support, Research Motivations, and Science Degree Aspirations. The alignment of these latent factors with SDT further suggests that this framework may be useful for capturing the variation associated with these research experiences. The design of this survey helps account for the within-subject variability, allows for meaningful conclusions with smaller sample sizes, and may prove a valuable evaluation tool small programs such as UREs. Further implementation of this framework may help identify resources that motivate students toward STEM careers and enable students, and particularly those from historically under-represented groups to reach their potential in STEM disciplines

    When good news leads to bad choices

    Get PDF
    Pigeons and other animals sometimes deviate from optimal choice behavior when given informative signals for delayed outcomes. For example, when pigeons are given a choice between an alternative that always leads to food after a delay and an alternative that leads to food only half of the time after a delay, preference changes dramatically depending on whether the stimuli during the delays are correlated with (signal) the outcomes or not. With signaled outcomes, pigeons show a much greater preference for the suboptimal alternative than with unsignaled outcomes. Key variables and research findings related to this phenomenon are reviewed, including the effects of durations of the choice and delay periods, probability of reinforcement, and gaps in the signal. We interpret the available evidence as reflecting a preference induced by signals for good news in a context of uncertainty. Other explanations are briefly summarized and compared

    PET Imaging of Soluble Yttrium-86-Labeled Carbon Nanotubes in Mice

    Get PDF
    The potential medical applications of nanomaterials are shaping the landscape of the nanobiotechnology field and driving it forward. A key factor in determining the suitability of these nanomaterials must be how they interface with biological systems. Single walled carbon nanotubes (CNT) are being investigated as platforms for the delivery of biological, radiological, and chemical payloads to target tissues. CNT are mechanically robust graphene cylinders comprised of sp(2)-bonded carbon atoms and possessing highly regular structures with defined periodicity. CNT exhibit unique mechanochemical properties that can be exploited for the development of novel drug delivery platforms. In order to evaluate the potential usefulness of this CNT scaffold, we undertook an imaging study to determine the tissue biodistribution and pharmacokinetics of prototypical DOTA-functionalized CNT labeled with yttrium-86 and indium-111 ((86)Y-CNT and (111)In-CNT, respectively) in a mouse model.The (86)Y-CNT construct was synthesized from amine-functionalized, water-soluble CNT by covalently attaching multiple copies of DOTA chelates and then radiolabeling with the positron-emitting metal-ion, yttrium-86. A gamma-emitting (111)In-CNT construct was similarly prepared and purified. The constructs were characterized spectroscopically, microscopically, and chromatographically. The whole-body distribution and clearance of yttrium-86 was characterized at 3 and 24 hours post-injection using positron emission tomography (PET). The yttrium-86 cleared the blood within 3 hours and distributed predominantly to the kidneys, liver, spleen and bone. Although the activity that accumulated in the kidney cleared with time, the whole-body clearance was slow. Differential uptake in these target tissues was observed following intravenous or intraperitoneal injection.The whole-body PET images indicated that the major sites of accumulation of activity resulting from the administration of (86)Y-CNT were the kidney, liver, spleen, and to a much less extent the bone. Blood clearance was rapid and could be beneficial in the use of short-lived radionuclides in diagnostic applications

    The structural basis of bacterial manganese import

    Get PDF
    肺炎球菌が細胞内にマンガンイオンを取り込むしくみ --膜輸送体PsaBCの立体構造の解明--. 京都大学プレスリリース. 2021-09-15.Metal ions are essential for all forms of life. In prokaryotes, ATP-binding cassette (ABC) permeases serve as the primary import pathway for many micronutrients including the first-row transition metal manganese. However, the structural features of ionic metal transporting ABC permeases have remained undefined. Here, we present the crystal structure of the manganese transporter PsaBC from Streptococcus pneumoniae in an open-inward conformation. The type II transporter has a tightly closed transmembrane channel due to “extracellular gating” residues that prevent water permeation or ion reflux. Below these residues, the channel contains a hitherto unreported metal coordination site, which is essential for manganese translocation. Mutagenesis of the extracellular gate perturbs manganese uptake, while coordination site mutagenesis abolishes import. These structural features are highly conserved in metal-specific ABC transporters and are represented throughout the kingdoms of life. Collectively, our results define the structure of PsaBC and reveal the features required for divalent cation transport

    The Time to Act Is Now: Addressing the Challenges of Being a Student, Staff, or Faculty Member at DU While Also Being a Parent to Young Children

    Get PDF
    The growing number of undergraduate and graduate students who are simultaneously raising children while attending school requires the attention of institutions that want to support their students through the completion of their intended program. Compared to traditional students, these students have greater time and financial restraints, lower graduation rates, and require accommodation, support, and resources to help them maintain their academic standing. This issue is not isolated to just students however. Staff and faculty at academic institutions are also balancing their family and work responsibilities. With an increase in the number of households where one or two adults work full time, more institutional employees are having to negotiate issues of childcare, parental leave, and the ways in which their family responsibilities are perceived by colleagues and employers. In 2017, it was found that many DU community members were struggling with issues of childcare, a child friendly environment at work, and institutional policies related to childcare at the University. These findings led to a study, conducted by the Applied Anthropology class of 2018, aimed at identifying solutions and recommendations for the aforementioned challenges. The study was exploratory and utilized mixed qualitative data collection and analysis methods. The class conducted interviews, surveys, and archival research and used thematic analysis techniques to identify overarching themes that informed the findings and suggestions of this project. Through this research three major needs were identified: clear communication of policies, accommodations for students, and on-site day care. Respondents from this and previous studies at DU identified that classroom policies, policies regarding parental leave, available childcare, and Fisher were being communicated either ineffectively or inaccurately. This has led to confusion, frustration, feelings of job insecurity, and unmet expectations regarding what resources and support DU actually offers parents. There is also a lack of policies in place for student parents, which makes creating schedules and fulfilling academic requirements more challenging for these nontraditional students. The most significant issue identified however was the lack of childcare at DU and the desire for an on-site daycare center. Respondents explained that Denver has a limited number of available, convenient, and affordable daycare options, that Fisher is not meeting their needs, and that they would like to see a facility designed specifically for DU students, staff, and faculty. In response to these challenges, this study suggests the assemblage and dissemination of accurate and clearly communicated childcare related policies, the creation of policies for student parents, and an on-site daycare facility for the DU community. Research and efforts to understand and alleviate these challenges have occurred at DU since the 1970s, and many of the identified needs and desired solutions have not changed over the past fifty years. However, because previous efforts have been powered by those in need of services, the momentum behind each effort has inevitably dissolved. A way to accomplish and sustain these suggestions and actively work towards making DU a more child and family friendly campus is by creating a permanent employee position at DU to handle these issues. This would help centralize information and policies, assist with their clear communication, and focus consistent and sustainable efforts towards helping DU students, staff, and faculty balance their work and family life

    Improving Together: A National Framework for Quality and GP Clusters in Scotland

    Get PDF
    Improving together will complement the development of the Scottish national GP contract that sets out the role of GPs and their important contribution as clinical leaders and expert medical generalists working in a community setting. This framework will be reviewed by the Scottish Government and the Scottish General Practitioners Committee of the BMA on a periodic basis, attentive to feedback from those involved in delivering its intent. As such, it is a framework that will develop to its full potential over time, as elements of the transformation of primary care in Scotland create the capacity to do so

    Increased site 1 affinity improves biopotency of porcine growth hormone - Evidence against diffusion dependent receptor dimerization

    Get PDF
    Based on phage display optimization studies with human growth hormone (GH), it is thought that the biopotency of GH cannot be increased. This is proposed to be a result of the affinity of the first receptor for hormone far exceeding that which is required to trap the hormone long enough to allow diffusion of the second receptor to form the ternary complex, which initiates signaling. We report here that despite similar site 1 kinetics to the hGH/hGH receptor interaction, the potency of porcine GH for its receptor can be increased up to 5-fold by substituting hGH residues involved in site 1 binding into pGH. Based on extensive mutations and BIAcore studies, we show that the higher potency and site 1 affinity of hGH for the pGHR is primarily a result of a decreased off-rate associated with residues in the extended loop between helices 1 and 2 that interact with the two key tryptophans Trp(104) and Trp(169) in the receptor binding hot spot. Our mutagenic analysis has also identified a second determinant (Lys(165)), which in addition to His(169), restricts the ability of non-primate hormones to activate hGH receptor. The increased biopotency of GH that we observe can be explained by a model for GH receptor activation where subunit alignment is critical for effective signaling

    SNP Array Karyotyping Allows for the Detection of Uniparental Disomy and Cryptic Chromosomal Abnormalities in MDS/MPD-U and MPD

    Get PDF
    We applied single nucleotide polymorphism arrays (SNP-A) to study karyotypic abnormalities in patients with atypical myeloproliferative syndromes (MPD), including myeloproliferative/myelodysplastic syndrome overlap both positive and negative for the JAK2 V617F mutation and secondary acute myeloid leukemia (AML). In typical MPD cases (N = 8), which served as a control group, those with a homozygous V617F mutation showed clear uniparental disomy (UPD) of 9p using SNP-A. Consistent with possible genomic instability, in 19/30 MDS/MPD-U patients, we found additional lesions not identified by metaphase cytogenetics. In addition to UPD9p, we also have detected UPD affecting other chromosomes, including 1 (2/30), 11 (4/30), 12 (1/30) and 22 (1/30). Transformation to AML was observed in 8/30 patients. In 5 V617F+ patients who progressed to AML, we show that SNP-A can allow for the detection of two modes of transformation: leukemic blasts evolving from either a wild-type jak2 precursor carrying other acquired chromosomal defects, or from a V617F+ mutant progenitor characterized by UPD9p. SNP-A-based detection of cryptic lesions in MDS/MPD-U may help explain the clinical heterogeneity of this disorder
    corecore