Health information behavior research with marginalized populations

As part of an increasingly vibrant area of research, information behavior scholars have shown that traditionally marginalized populations (e.g., older adults, LGBTQ people, people of color, low‐income people and people with chronic diseases or disabilities) may have distinct health information needs and information behaviors. These differences may arise from unique patterns in marginalized groups’ life experiences, health risks and burdens, social networks and available resources, as well as dynamics of social marginalization and exclusionary service design. This subfield of information studies challenges established notions of health information‐seeking behaviours to further develop theories and models, as well as propose new models for information services and technologies. The unique characteristics of marginalized populations have necessitated the development of novel research approaches and methods, as well as interdisciplinary collaborations and community‐based partnerships. This panel invites audience members to think critically about what it means to engage marginalized populations in research and the methods and approaches needed to do so in a health context. It will also allow participants to broaden their understanding about the health information‐seeking behaviors of marginalized populations. Panelists will introduce and contextualize marginalized populations’ health information‐seeking behaviours and explore potential or existing connections between themes from a variety of disciplines. Following a brief introduction and presentations from five panelists (who are themselves exploring marginalized populations’ health information‐seeking behaviours), there will be an open discussion session with the audience in a World Café format.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/139108/1/pra214505401073.pd

An Analysis of Variability in Power Output During Indoor and Outdoor Cycling Time-Trials

PURPOSE::Regulation of power output during cycling encompasses the integration of internal and external demands to maximise performance. However, relatively little is known about variation in power output in response to the external demands of outdoor cycling. We compared mean power output and the magnitude of power output variability and structure during a 20-min time-trial performed indoors and outdoors.METHODS::Twenty male competitive cyclists (V̇O2peak 60.4 ± 7.1 mL·kg-1·min-1) performed two randomised maximal 20-min time-trial tests i) outdoors at a cycle-specific racing circuit or ii) indoors on a laboratory-based electromagnetically braked training ergometer, 7 days apart. Power output was sampled at 1 Hz and collected on the same bike equipped with a portable power meter in both tests.RESULTS::Twenty-min time-trial performance indoor (280 ± 44 W) was not different from outdoor (284 ± 41 W) (P = 0.256), showing a strong correlation (r = 0.94; P < 0.001). Within-person SD was greater outdoors (69 ± 21 W) compared to indoors (33 ± 10 W) (P < 0.001). Increased variability was observed across all frequencies in data from outdoor cycling compared to indoors (P < 0.001) except for the very slowest frequency bin (<0.0033 Hz, P = 0.930).CONCLUSIONS::Our findings indicate a greater magnitude of variability in power output during cycling outdoors. This suggests that constraints imposed by the external environment lead to moderate and high frequency fluctuations in power output. Therefore, indoor testing protocols should be designed to reflect the external demands of cycling outdoors

Three-Dimensional Microfluidic Tri-Culture Model of the Bone Marrow Microenvironment for Study of Acute Lymphoblastic Leukemia

Acute lymphoblastic leukemia (ALL) initiates and progresses in the bone marrow, and as such, the marrow microenvironment is a critical regulatory component in development of this cancer. However, ALL studies were conducted mainly on flat plastic substrates, which do not recapitulate the characteristics of marrow microenvironments. To study ALL in a model of in vivo relevance, we have engineered a 3-D microfluidic cell culture platform. Biologically relevant populations of primary human bone marrow stromal cells, osteoblasts and human leukemic cells representative of an aggressive phenotype were encapsulated in 3-D collagen matrix as the minimal constituents and cultured in a microfluidic platform. The matrix stiffness and fluidic shear stress were controlled in a physiological range. The 3-D microfluidic as well as 3-D static models demonstrated coordinated cell-cell interactions between these cell types compared to the compaction of the 2-D static model. Tumor cell viability in response to an antimetabolite chemotherapeutic agent, cytarabine in tumor cells alone and tri-culture models for 2-D static, 3-D static and 3-D microfluidic models were compared. The present study showed decreased chemotherapeutic drug sensitivity of leukemic cells in 3-D tri-culture models from the 2-D models. The results indicate that the bone marrow microenvironment plays a protective role in tumor cell survival during drug treatment. The engineered 3-D microfluidic tri-culture model enables systematic investigation of effects of cell-cell and cell-matrix interactions on cancer progression and therapeutic intervention in a controllable manner, thus improving our limited comprehension of the role of microenvironmental signals in cancer biology

Three-Dimensional Microfluidic Tri-Culture Model of the Bone Marrow Microenvironment for Study of Acute Lymphoblastic Leukemia

Acute lymphoblastic leukemia (ALL) initiates and progresses in the bone marrow, and as such, the marrow microenvironment is a critical regulatory component in development of this cancer. However, ALL studies were conducted mainly on flat plastic substrates, which do not recapitulate the characteristics of marrow microenvironments. To study ALL in a model of in vivo relevance, we have engineered a 3-D microfluidic cell culture platform. Biologically relevant populations of primary human bone marrow stromal cells, osteoblasts and human leukemic cells representative of an aggressive phenotype were encapsulated in 3-D collagen matrix as the minimal constituents and cultured in a microfluidic platform. The matrix stiffness and fluidic shear stress were controlled in a physiological range. The 3-D microfluidic as well as 3-D static models demonstrated coordinated cell-cell interactions between these cell types compared to the compaction of the 2-D static model. Tumor cell viability in response to an antimetabolite chemotherapeutic agent, cytarabine in tumor cells alone and tri-culture models for 2-D static, 3-D static and 3-D microfluidic models were compared. The present study showed decreased chemotherapeutic drug sensitivity of leukemic cells in 3-D tri-culture models from the 2-D models. The results indicate that the bone marrow microenvironment plays a protective role in tumor cell survival during drug treatment. The engineered 3-D microfluidic tri-culture model enables systematic investigation of effects of cell-cell and cell-matrix interactions on cancer progression and therapeutic intervention in a controllable manner, thus improving our limited comprehension of the role of microenvironmental signals in cancer biology

Image-Based Analysis to Dissect Vertical Distribution and Horizontal Asymmetry of Conspecific Root System Interactions in Response to Planting Densities, Nutrients and Root Exudates in \u3cem\u3eArabidopsis thaliana\u3c/em\u3e

Intraspecific competition is an important plant interaction that has been studied extensively aboveground, but less so belowground, due to the difficulties in accessing the root system experimentally. Recent in vivo and in situ automatic imaging advances help understand root system architecture. In this study, a portable imaging platform and a scalable transplant technique were applied to test intraspecific competition in Arabidopsis thaliana. A single green fluorescent protein labeled plant was placed in the center of a grid of different planting densities of neighboring unlabeled plants or empty spaces, into which different treatments were made to the media. The root system of the central plant showed changes in the vertical distribution with increasing neighbor density, becoming more positively kurtotic, and developing an increasing negative skew with time. Horizontal root distribution was initially asymmetric, but became more evenly circular with time, and mean direction was not affected by the presence of adjacent empty spaces as initially hypothesized. To date, this is the first study to analyze the patterns of both vertical and horizontal growth in conspecific root systems. We present a portable imaging platform with simplicity, accessibility, and scalability, to capture the dynamic interactions of plant root systems

Applied Research on Leadership in Community Colleges

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68252/2/10.1177_009155218501200407.pd

Evidence for a subtractive component in motion adaptation

Adaptation to a moving stimulus changes the perception of a stationary grating and also reduces contrast sensitivity to the adaptor. We determined whether the first effect could be predicted from the second. The contrast discrimination (T vs C) function for a drifting 7.5 Hz grating test stimulus was determined when observers were adapted to a low contrast (0.075) grating of the same spatial and temporal frequency, moving in either the same or the opposite direction as the test. The effect of an adaptor moving in the same direction was to move the T vs C function upwards and to the right, in a manner consistent with an increase in divisive inhibition. We also measured the effect of adaptation on the motion-null point for a counterphasing grating containing two components, one moving in the same direction as the adaptor and the other in the opposite direction. Adaptation increased the amount of contrast of the adapted component required to achieve the motion-null point. However, this shift could not be predicted from the effects of adaptation on contrast sensitivity. In particular, the balance point was shifted in gratings of high contrast where there was no effect of adaptation on contrast discrimination. We suggest that adaptation has a subtractive (recalibration) effect in addition to its effects on the contrast transduction function, and that this subtractive effect may explain the movement after-effect seen with stationary tests

Characterizing Transiting Extrasolar Planets with Narrow-Band Photometry and GTC/OSIRIS

We report the first extrasolar planet observations from the 10.4-m Gran Telescopio Canarias (GTC), currently the world's largest, fully steerable, single-aperture optical telescope. We used the OSIRIS tunable filter imager on the GTC to acquire high-precision, narrow-band photometry of the transits of the giant exoplanets, TrES-2b and TrES-3b. We obtained near-simultaneous observations in two near-infrared (NIR) wavebands (790.2 and 794.4 +/- 2.0 nm) specifically chosen to avoid water vapor absorption and skyglow so as to minimize the atmospheric effects that often limit the precision of ground-based photometry. Our results demonstrate a very-high photometric precision with minimal atmospheric contamination despite relatively poor atmospheric conditions and some technical problems with the telescope. We find the photometric precision for the TrES-2 observations to be 0.343 and 0.412 mmag for the 790.2 and 794.4 nm light curves, and the precision of the TrES-3 observations was found to be 0.470 and 0.424 mmag for the 790.2 and 794.4 nm light curves. We also discuss how future follow-up observations of transiting planets with this novel technique can contribute to the characterization of Neptune- and super-Earth-size planets to be discovered by space-based missions like CoRoT and Kepler, as well as measure atmospheric properties of giant planets, such as the strength of atmospheric absorption features.Comment: 9 pages, including 3 figures and 2 tables; accepted for publication in MNRA