2,600 research outputs found
Seeking an Intentional Crossroads: Working Towards an Understanding of Community Building in Hawaiâi Public Libraries
Public libraries in Hawaiâi serve one of the most diverse populations in the United States. With 51 branch locations across six islands, Hawaii\u27s public libraries are central hubs for citizens, where community building can take place. This paper seeks to explore ways in which community building takes place at public libraries in Hawaiâi. Through on-site visits at public libraries, observations of training sessions of participants of a Hawaiâi-based public library professional development program (Hui âEkolu), and informal interviews with local public library patrons, key themes, reflections and analysis convey a common question across all groups: âWhat is a Native Hawaiian Library?â âWhat is Hawaiian librarianship?â This research is at an emerging stage where such meaningful questions are pointing towards a need to center Indigenous Hawaiian ways of knowing and perceiving public services in libraries as a primary tenet of cultural competence for public library workers in Hawaiâi. As a federally funded grant program, Hui âEkolu is an innovative opportunity to explore questions that emerge as an inquiry-based approach to determining what professional learning and development can look like within place-based contexts
Tissue biodistribution and tumor targeting of near-infrared labelled anti-CD38 antibody-drug conjugate in preclinical multiple myeloma
Daratumumab (DARA) is an FDA-approved high-affinity monoclonal antibody targeting CD38 that has shown promising therapeutic efficacy in double refractory multiple myeloma (MM) patients. Despite the well-established clinical efficacy of DARA, not all heavily pretreated patients respond to single-agent DARA, and the majority of patients who initially respond eventually progress. Antibody-drug conjugates (ADCs) combine the highly targeted tumor antigen recognition of antibodies with the cell killing properties of chemotherapy for effective internalization and processing of the drug. In this study, we evaluated the anti-tumor efficacy of DARA conjugated to the maytansine derivative, mertansine (DM1), linked via a non-cleavable bifunctional linker. The ADC was labelled with the near-infrared (NIR) fluorophore IRDye800 (DARA-DM1-IR) to evaluate its stability, biodistribution and pharmacokinetic
Characterizing Polytobacco Use Trajectories and Their Associations With Substance Use and Mental Health Across Mid-Adolescence.
Background:Polytobacco product use is suspected to be common, dynamic across time, and increase risk for adverse behavioral outcomes. We statistically modeled characteristic types of polytobacco use trajectories during mid-adolescence and tested their prospective association with substance use and mental health problems. Methods:Adolescents (N = 3393) in Los Angeles, CA, were surveyed semiannually from 9th to 11th grade. Past 6-month combustible cigarette, e-cigarette, or hookah use (yes/no) over four assessments were analyzed using parallel growth mixture modeling to identify a parsimonious set of polytobacco use trajectories. A tobacco product use trajectory group was used to predict substance use and mental health at the fifth assessment. Results:Three profiles were identified: (1) tobacco nonusers (N = 2291, 67.5%) with the lowest use prevalence (<3%) of all products across all timepoints; (2) polyproduct users (N = 920, 27.1%) with moderate use prevalence of each product (8-35%) that escalated for combustible cigarettes but decreased for e-cigarettes and hookah across time; and (3) chronic polyproduct users (N = 182, 5.4%) with high prevalence of each product use (38-86%) that escalated for combustible cigarettes and e-cigarettes. Nonusers, polyproduct users, and chronic polyproduct users reported successively higher alcohol, marijuana, and illicit drug use and ADHD at the final follow-up, respectively. Both tobacco using groups (vs. nonusers) reported greater odds of depression and anxiety at the final follow-up but did not differ from each other. Conclusions:Adolescent polytobacco use may involve a common moderate risk trajectory and a less common high-risk chronic trajectory. Both trajectories predict substance use and mental health symptomology. Implications:Variation in use and co-use of combustible cigarette, e-cigarette, and hookah use in mid-adolescence can be parsimoniously characterized by a small set common trajectory profiles in which polyproduct use are predominant patterns of tobacco product use, which predict adverse behavioral outcomes. Prevention and policy addressing polytobacco use (relative to single product use) may be optimal tobacco control strategies for youth, which may in turn prevent other forms of substance use and mental health problems
Spectral changes during the 0.1-4 Hz quasi-periodic oscillations in the black hole X-ray binary XTE J1550-564
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Physics, 2005.Includes bibliographical references (p. 61-62).In this thesis, we describe the analysis of 0.1-4 Hz quasi-periodic oscillations (QPOs) of the black hole X-ray binary XTE J1550-564 using data obtained with the Rossi X-ray Timing Explorer (RXTE) satellite. Data from 13 consecutive observations spanning eight days were included in this analysis. By comparing the spectra of the source when it is in the high intensity phase with the low intensity phase of its QPO cycle, we hoped to gain insight into the cause of QPOs and how they relate to structures and processes in the vicinity of black holes. Like observations from the black hole X-ray binary GRS 1915+105 (Miller and Homan 2005), our observations from XTE J1550-564 showed a significant difference in the Fe ... line equivalent width between the high and low intensities of the QPO for 6 of 13 observations. However, 2 of 13 observations exhibited the opposite effect in that the Fe K [alpha] line equivalent width actually dropped significantly during periods of high intensity. Moreover, we found that the integrated flux of the Fe K [alpha] line was proportional to the flux of the continuum in 5 of 13 observations. Despite these competing effects, the ratios of the low intensity and high intensity spectra indicate an increase in the QPO strength up to about 10 keV, above which it decreases only slightly. We also found dramatic changes in the QPO strength at low energies as the QPO frequency increases. We believe this to be the result of an increase in relative contributions to the spectra as the disk blackbody component becomes more important.(Cont.) In this thesis, we discuss five possible spectral models to explain QPOs based on the behavior of Fe K [alpha] emission lines. Then we describe whether or not our results agree with those predictions. Although our results show correlations similar to those found by Miller and Homan (2005), they also show anti-correlations in several observations. Our results support Miller and Homan's suggestion of a link between discrete timing features (QPOs) and spectral features (Fe K [alpha] emission lines) which occur in the inner disk around black holes. Our work shows that current explanations for QPOs have some physical basis, suggesting that QPOs are due to either a quasi-periodically changing reflector area in the accretion disk or an episodic modulation of the hard flux component in the corona or jets that irradiates the accretion disk. Our results also suggest that perhaps the correct model is something more complex that goes beyond current models and is able to explain the multiple effects observed in the Fe K [alpha] line.by Steven N. Cho.S.M
Responsive hydrogel sensor for monitoring antibody production
Precise control over the biomanufacturing process is crucial for maximizing yield and quality of monoclonal antibodies (mAbs); however, the industry does not have sensors capable of continuously monitoring either mAb yield or quality. Consequently, this production is plagued with poor quality control, reduced productivity, and increased costs. To develop such a sensor, we investigated the use of aptamers selective to human immunoglobulin G (IgG, sub-type of mAbs). First, we investigated the physiochemical properties of six different aptamers that bind to two distinct regions of the protein as well as tested their the binding affinity to human IgG, before and after standard sterilization procedures (autocalve and gamma irradation), using surface plasmon resonance (SPR, Figure 1). Chemical modification procedures were developed for immobilization of the aptamers onto a biotin capture sensor chip for use in SPR. Based on these results, two aptamers were selected which bind to separate regions of IgG, which have optimal physiochemical properties and have strong binding affinity to IgG. Similarly, the aptamers were modified to covalently bond and incorporate into a hydrogel network creating an IgG-sensitive hydrogel. In the presence of IgG in solution, both immobilized aptamers bind to the IgG molecule and form a new crosslink which subsequently causes shrinking (volume reduction) of the hydrogel [1]. This change in volume is monitored using our patent-pending magnetic transduction technique [2]. The degree of hydrogel shrinkage is measured using a magnetometer chip and fixing a permanent magnet to the hydrogel surface. An electronic reader with the magnetometer transduces the hydrogel response into an electrical signal. Response tests using this setup were performed in four different complex environments including industrial cell culture medium. The results show that this IgG-sensitive hydrogel is stable to autoclave and gamma irradition and responds to increasing and decreasing concentrations of IgG in various solutions (Figure 2). The magnitude of hydrogel response is used to correlate the change in IgG concentraion.
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