39 research outputs found
What Do They Say? Students from a Private, Faith-Based, Four-Year University Share their Perspectives on College as a Mentoring Environment
Research indicates that the term mentor in the context of higher education currently has multiple definitions and is used to describe a variety of programs, efforts, and formal as well as informal activities. In recent years, interdisciplinary perspectives on traditional undergraduate students have been converging around the idea that the functions and characteristics of mentoring students could be shared across the institution, creating what Daloz Parks (2000) has called a mentoring environment. This sharing of responsibility has the possibility to address what Baxter Magolda (2009) has recently identified as missing in higher education, a holistic, theoretical perspective to promote the learning and developing of the whole student (p. 621). A review of the literature from psychology, sociology, and student affairs documents this attempt to consider a more integrated and collaborative approach to college as a mentoring environment. The purpose of this research was to understand better how these students perceived, received, understood, and experienced one aspect of their college experience: mentoring. This qualitative study used thematic analysis to consider the input of 12 undergraduate students who have recently or will soon graduate from a private, four-year, faith-based liberal arts university in Southern California. The study was guided by the following research questions: How do graduating seniors attending a private, traditional, faith-based, four-year liberal-arts university describe mentoring? How do the students describe the formal and/or informal mentoring they have received during their college years? What suggestions do the students have for improving the university\u27s formal and informal mentoring efforts? Based on extensive data analysis, findings revealed that students spoke to the transformative nature of relational and participatory experiences with faculty, staff and administrators as well as the value of opportunities to interact with several important adult mentors. Irrespective of efforts categorized as formal or informal mentoring, participants spoke more to the value of campus leaders showing an interest in their personal and professional development. Recommendations are offered for faculty, staff and administrators regarding a more holistic and collaborative approach to college as a mentoring environment. Beyond this study, the recommendations discussed should be considered based on individual, institutional suitability
Impact of oral cyclophosphamide on health-related quality of life in patients with active scleroderma lung disease: Results from the scleroderma lung study
Objective To assess the impact of cyclophosphamide (CYC) on the health-related quality of life (HRQOL) of patients with scleroderma after 12 months of treatment. Methods One hundred fifty-eight subjects participated in the Scleroderma Lung Study, with 79 each randomized to CYC and placebo arms. The study evaluated the results of 3 measures of health status: the Short Form 36 (SF-36), the Health Assessment Questionnaire (HAQ) disability index (DI), and Mahler's dyspnea index, and the results of 1 preference-based measure, the SF-6D. The differences in the HRQOL between the 2 groups at 12 months were calculated using a linear mixed model. Responsiveness was evaluated using the effect size. The proportion of subjects in each treatment group whose scores improved at least as much as or more than the minimum clinically important difference (MCID) in HRQOL measures was assessed. Results After adjustment for baseline scores, differences in the HAQ DI, SF-36 role physical, general health, vitality, role emotional, mental health scales, and SF-36 mental component summary (MCS) score were statistically significant for CYC versus placebo ( P < 0.05). Effect sizes were negligible (<0.20) for all of the scales of the SF-36, HAQ DI, and SF-6D at 12 months. In contrast, a higher proportion of patients who received CYC achieved the MCID compared with placebo in the HAQ DI score (30.9% versus 14.8%), transitional dyspnea index score (46.4% versus 12.7%), SF-36 MCS score (33.3% versus 18.5%), and SF-6D score (21.3% versus 3.8%). Conclusion One year of treatment with CYC leads to an improvement in HRQOL in patients with scleroderma lung disease.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/56039/1/22580_ftp.pd
New models and online calculator for predicting non-sentinel lymph node status in sentinel lymph node positive breast cancer patients
<p>Abstract</p> <p>Background</p> <p>Current practice is to perform a completion axillary lymph node dissection (ALND) for breast cancer patients with tumor-involved sentinel lymph nodes (SLNs), although fewer than half will have non-sentinel node (NSLN) metastasis. Our goal was to develop new models to quantify the risk of NSLN metastasis in SLN-positive patients and to compare predictive capabilities to another widely used model.</p> <p>Methods</p> <p>We constructed three models to predict NSLN status: recursive partitioning with receiver operating characteristic curves (RP-ROC), boosted Classification and Regression Trees (CART), and multivariate logistic regression (MLR) informed by CART. Data were compiled from a multicenter Northern California and Oregon database of 784 patients who prospectively underwent SLN biopsy and completion ALND. We compared the predictive abilities of our best model and the Memorial Sloan-Kettering Breast Cancer Nomogram (Nomogram) in our dataset and an independent dataset from Northwestern University.</p> <p>Results</p> <p>285 patients had positive SLNs, of which 213 had known angiolymphatic invasion status and 171 had complete pathologic data including hormone receptor status. 264 (93%) patients had limited SLN disease (micrometastasis, 70%, or isolated tumor cells, 23%). 101 (35%) of all SLN-positive patients had tumor-involved NSLNs. Three variables (tumor size, angiolymphatic invasion, and SLN metastasis size) predicted risk in all our models. RP-ROC and boosted CART stratified patients into four risk levels. MLR informed by CART was most accurate. Using two composite predictors calculated from three variables, MLR informed by CART was more accurate than the Nomogram computed using eight predictors. In our dataset, area under ROC curve (AUC) was 0.83/0.85 for MLR (n = 213/n = 171) and 0.77 for Nomogram (n = 171). When applied to an independent dataset (n = 77), AUC was 0.74 for our model and 0.62 for Nomogram. The composite predictors in our model were the product of angiolymphatic invasion and size of SLN metastasis, and the product of tumor size and square of SLN metastasis size.</p> <p>Conclusion</p> <p>We present a new model developed from a community-based SLN database that uses only three rather than eight variables to achieve higher accuracy than the Nomogram for predicting NSLN status in two different datasets. </p
Continuum-based models and concepts for the transport of nanoparticles in saturated porous media: A state-of-the-science review
Environmental applications of nanoparticles (NP) increasingly result in widespread NP distribution within porous media where they are subject to various concurrent transport mechanisms including irreversible deposition, attachment/detachment (equilibrium or kinetic), agglomeration, physical straining, site-blocking, ripening, and size exclusion. Fundamental research in NP transport is typically conducted at small scale, and theoretical mechanistic modeling of particle transport in porous media faces challenges when considering the simultaneous effects of transport mechanisms. Continuum modeling approaches, in contrast, are scalable across various scales ranging from column experiments to aquifer. They have also been able to successfully describe the simultaneous occurrence of various transport mechanisms of NP in porous media such as blocking/straining or agglomeration/deposition/detachment. However, the diversity of model equations developed by different authors and the lack of effective approaches for their validation present obstacles to the successful robust application of these models for describing or predicting NP transport phenomena.
This review aims to describe consistently all the important NP transport mechanisms along with their representative mathematical continuum models as found in the current scientific literature. Detailed characterizations of each transport phenomenon in regards to their manifestation in the column experiment outcomes, i.e., breakthrough curve (BTC) and residual concentration profile (RCP), are presented to facilitate future interpretations of BTCs and RCPs. The review highlights two NP transport mechanisms, agglomeration and size exclusion, which are potentially of great importance in controlling the fate and transport of NP in the subsurface media yet have been widely neglected in many existing modeling studies.
A critical limitation of the continuum modeling approach is the number of parameters used upon application to larger scales and when a series of transport mechanisms are involved. We investigate the use of simplifying assumptions, such as the equilibrium assumption, in modeling the attachment/detachment mechanisms within a continuum modelling framework. While acknowledging criticisms about the use of this assumption for NP deposition on a mechanistic (process) basis, we found that its use as a description of dynamic deposition behavior in a continuum model yields broadly similar results to those arising from a kinetic model. Furthermore, we show that in two dimensional (2-D) continuum models the modeling efficiency based on the Akaike information criterion (AIC) is enhanced for equilibrium vs kinetic with no significant reduction in model performance. This is because fewer parameters are needed for the equilibrium model compared to the kinetic model.
Two major transport regimes are identified in the transport of NP within porous media. The first regime is characterized by higher particle-surface attachment affinity than particle-particle attachment affinity, and operative transport mechanisms of physicochemical filtration, blocking, and physical retention. The second regime is characterized by the domination of particle-particle attachment tendency over particle-surface affinity. In this regime although physicochemical filtration as well as straining may still be operative, ripening is predominant together with agglomeration and further subsequent retention. In both regimes careful assessment of NP fate and transport is necessary since certain combinations of concurrent transport phenomena leading to large migration distances are possible in either case
The Mortal Sea: Fishing the Atlantic in the Age of Sail
Overfishing is often thought of as a contemporary problem. Jeff Bolster’s presentation reveals humans transforming the sea long before factory trawlers turned fishing from a hand-liner’s art into an industrial enterprise. The western Atlantic’s legendary fishing banks, stretching from Cape Cod to Newfoundland, have attracted fishermen for more than five hundred years. In his innovative re-telling of that supposedly well-known sea story, Bolster, a historian and professional mariner, reveals possibilities unlocked through a focus on Environmental Humanities. Blending marine biology, ecological insight, and a remarkable cast of characters — from notable explorers to scientists to an army of unknown fishermen — this talk, based on his book of the same name, illuminates a story that is both ecological and human: the prelude to an environmental disaster.
Jeffrey Bolster is a Professor Emeritus of History at the University of New Hampshire. His expertise lies in the areas of maritime history, early American history, African American history, New Hampshire history, and environmental history of Northwest Atlantic commercial fisheries. Bolster states he “is equally at home with a deck under [his] feet or with the treasures of a research library spread before [him].”
He is the author of a number of publications including the best-selling book, Black Jacks: African American Seamen in the Age of Sail and his most recent book, The Mortal Sea: Fishing the Atlantic in the Age of Sail. The latter won the American Historical Association’s 2013 Albert J. Beveridge Prize and 2013 James Rawley Prize in Atlantic History. The book also won the North American Society for Oceanic History’s John Lyman Book Award for the best book in U.S. Maritime History. Columbia University named Bolster one of two recipients of the 2013 Bancroft Prize, which is considered one of the most distinguished academic awards in the field of history
Characterizing the Influence of Fracture Density on Network Scale Transport
The topology of natural fracture networks is inherently linked to the structure of the fluid velocity field and transport therein. Here we study the impact of network density on flow and transport behaviors. We stochastically generate fracture networks of varying density and simulate flow and transport with a discrete fracture network model, which fully resolves network topology at the fracture scale. We study conservative solute trajectories with Lagrangian particle tracking and find that as fracture density decreases, solute channelization to large local fractures increases, thereby reducing plume spreading. Furthermore, in sparse networks mean particle travel distance increases and local network features, such as velocity zones where flow is counter to the primary pressure gradient, become increasingly important for transport. As the network density increases, network statistics homogenize and such local features have a reduced impact. We quantify local topological influence on transport behavior with an effective tortuosity parameter, which measures the ratio of total advective distance to linear distance at the fracture scale; large tortuosity values are correlated to slow‐velocity regions. These large tortuosity, slow‐velocity regions delay downstream transport and enhance tailing on particle breakthrough curves. Finally, we predict transport with an upscaled, Bernoulli spatial Markov random walk model and parameterize local topological influences with a novel tortuosity parameter. Bernoulli model predictions improve when sampling from a tortuosity distribution, as opposed to a fixed value as has previously been done, suggesting that local network topological features must be carefully considered in upscaled modeling efforts of fracture network systems.T. S. is supported by the National Science Foundation Graduate Research Fellowship under Grant DGE‐1841556. D. B. was supported by the US Army Research Office under Contract/Grant W911NF‐18‐1‐0338 and by the National Science Foundation under award CBET‐1803989. Los Alamos National Laboratory is operated by Triad National Security, LLC, for the National Nuclear Security Administration of U.S. Department of Energy (Contract 89233218CNA000001). J. D. H. acknowledges support from the LANL LDRD program office Grant 20180621ECR and DOE's Office of Science Basic Energy SciencesE3W1: LA‐UR‐19‐27671. M. D. acknowledges funding from the European Research Council under the European Union's Seventh Framework Programme (FP7/2007‐2013)/ ERC Grant Agreement 617511 (MHetScale). DFNWORKS and and simulation data can be obtained at GitHub (https://github.com/lanl/dfnWorks and https://github.com/tjsherman24/FractureNetworkDensity, respectively).Peer reviewe
Sustained phosphorylation of tyrosine hydroxylase at serine 40: a novel mechanism for maintenance of catecholamine synthesis
Tyrosine hydroxylase (TH) is the rate-limiting enzyme in catecholamine synthesis. Its activity is known to be controlled acutely (minutes) by phosphorylation and chronically (days) by protein synthesis. Using bovine adrenal chromaffin cells we found that nicotine, acting via nicotinic receptors, sustained the phosphorylation of TH at Ser40 for up to 48 h. Nicotine also induced sustained activation of TH, which for the first 24 h was completely independent of TH protein synthesis, and the phosphorylation of TH at Ser31. Imipramine did not inhibit the acute phosphorylation of TH at Ser40 or TH activation induced by nicotine, but did inhibit the sustained responses to nicotine seen at 24 h. The protein kinase(s) responsible for TH phosphorylation at Ser40 switched from being protein kinase C (PKC) independent in the acute phase to PKC dependent in the sustained phase. Sustained phosphorylation and activation of TH were also observed with histamine and angiotensin II. Sustained phosphorylation of TH at Ser40 provides a novel mechanism for increasing TH activity and this leads to increased catecholamine synthesis. Sustained phosphorylation of TH may be a selective target for drugs or pathology in neurons that contain TH and synthesize dopamine, noradrenaline or adrenaline