Flocculation of wall-deficient cells of \u3ci\u3eChlamydomonas reinhardtii\u3c/i\u3e mutant cw15 by calcium and methanol

Flocculation is a common and inexpensive method for harvesting algae from solution. After nitrogen starvation, it was shown that 83 + 3% of the wall-deficient cells of the cw 15 mutant of Chlamydomonas reinhardtii flocculated from 12 mL samples within 15 min after the addition of 15 mM calcium chloride at pH 8.4. Only 24 2% of the wildtype strain flocculated under these conditions, thus demonstrating how a simple mutation might facilitate process design. The data suggested that algae grown in waters with similar calcium concentrations (e.g. certain wastewaters) might be harvested through simple pH adjustment. It was also discovered that the addition of small amounts (\u3c5% v/v) of methanol could significantly reduce the calcium needed to achieve flocculation. Within 15 min after addition of 12 mM calcium chloride and 4.6% (v/v) methanol, 83 + 4% of cw15 cells flocculated. Methanol is fully recoverable by distillation, and its use might enable flocculation without further water salinization when media calcium concentrations fall short of 15 mM. It was further shown that substrates for and/or products of cellular growth affected flocculation adversely. Nearly 81% of cells flocculated from fresh medium compared to only 54% in spent medium

Interventions for increasing colorectal cancer screening uptake among African-American men: a systematic review and meta-analysis

This is a protocol of a systematic review

Alumni Voices: Celebrating Global Engagement

This session brought together UD alumni who had a wide array of global experiences while here on campus as students; they spoke on how those experiences impacted their lives and careers.https://ecommons.udayton.edu/global_voices_2/1006/thumbnail.jp

What is Your Prejudice? Predicting Prejudice Towards Greek Members

Greek membership has been linked to prejudice toward others (Rhoads, 1995), but little research has examined prejudice toward Greek members. Participants completed individual difference measures related to prejudice as well as measures of religiosity, political orientation, gender, Greek membership, and Greek myths. Participants who perceived Greek members as more like themselves held fewer negative stereotypes of and more positive attitudes toward Greek members. Contact, including being a Greek member oneself, was also related to warmer attitudes toward Greek members. Individual difference factors that have predicted prejudice toward other groups (e.g., based on ethnicity or sexual orientation; RWA, SDO) did not relate to prejudice, suggesting that predictors of prejudice may vary depending on whether group membership is voluntary and/or whether a group is high or low status

Publication trends among emergency medicine residents, fellows, and graduates and its relationship to future academic achievement

Purpose: Scholastic activity through research involvement is a fundamental aspect of a physician's training, and may have a significant influence on residency and fellowship match success. Despite this fact, little is known regarding the pursuit of academia and/or fellowships in emergency medicine graduates. In this review, we will (1) describe factors involved in academic research including peer-reviewed publications among emergency medicine residency graduates and (2) determine if a relationship exists between publication rates before, during, and after emergency medicine residency.Methods: Using a cross-sectional study design, we analyzed the research output of emergency medicine graduates and its relationship to future academic involvement from a random sample of 50 emergency medicine programs' graduates. Data were extracted for each graduate and analyzed using STATA 15.1 and Microsoft Excel. A public protocol is available here: https://osf.io/pwa6d/.Results: Using Doximity, we identified 238 emergency medicine residency programs of which we sampled 50. Of the 50 included programs, 6 programs were included, amounting in 154 graduates available for analysis. Of the 154 analyzed graduates, 97 (63.0%) were male, 91 (59.1%) were osteopathic graduates, and 91 (59.1%) had zero publications. Additionally, we found that 26/154 (16.9%) pursued academia and 16/164 (10.4%) pursued a fellowship, with 4/16 (25%) in medical toxicology and 4/16 (25%) in emergency medical services. The mean number of publications for each graduate was 0.87. Of the graduates with research, more research was published on average after graduation from residency (0.42) compared to before residency (0.17) and during residency (0.34).Conclusion: While a majority of psychiatry graduate's publications were post-residency, many publications occurred during residency, with the lowest number of publications occurring pre-residency

The non-dipolar magnetic fields of accreting T Tauri stars

Models of magnetospheric accretion on to classical T Tauri stars often assume that stellar magnetic fields are simple dipoles. Recently published surface magnetograms of BP Tau and V2129 Oph have shown, however, that their fields are more complex. The magnetic field of V2129 Oph was found to be predominantly octupolar. For BP Tau the magnetic energy was shared mainly between the dipole and octupole field components, with the dipole component being almost four times as strong as that of V2129 Oph. From the published surface maps of the photospheric magnetic fields we extrapolate the coronal fields of both stars, and compare the resulting field structures with that of a dipole. We consider different models where the disc is truncated at, or well-within, the Keplerian corotation radius. We find that although the structure of the surface magnetic field is particularly complex for both stars, the geometry of the larger scale field, along which accretion is occurring, is somewhat simpler. However, the larger scale field is distorted close to the star by the stronger field regions, with the net effect being that the fractional open flux through the stellar surface is less than would be expected with a dipole magnetic field model. Finally, we estimate the disc truncation radius, assuming that this occurs where the magnetic torque from the stellar magnetosphere is comparable to the viscous torque in the disc.Comment: 14 pages, 8 figures. Figures are reduced resolutio

Effect of W self-implantation and He plasma exposure on early-stage defect and bubble formation in tungsten

To determine the effect of pre-existing defects on helium-vacancy cluster nucleation and growth, tungsten samples were self-implanted with 1 MeV tungsten ions at varying fluences to induce radiation damage, then subsequently exposed to helium plasma in the MAGPIE linear plasma device. Positron annihilation lifetime spectroscopy was performed both immediately after self-implantation, and again after plasma exposure. After self-implantation vacancies clusters were not observed near the sample surface (<30 nm). At greater depths (30-150 nm) vacancy clusters formed, and were found to increase in size with increasing W-ion fluence. After helium plasma exposure in the MAGPIE linear plasma device at ∼300 K with a fluence of 1023 He-m-2, deep (30-150 nm) vacancy clusters showed similar positron lifetimes, while shallow (<30 nm) clusters were not observed. The intensity of positron lifetime signals fell for most samples after plasma exposure, indicating that defects were filling with helium. The absence of shallow clusters indicates that helium requires pre-existing defects in order to drive vacancy cluster growth at 300 K. Further samples that had not been pre-damaged with W-ions were also exposed to helium plasma in MAGPIE across fluences from 1 × 1022 to 1.2 × 1024 He-m-2. Samples exposed to fluences up to 1 × 1023 He-m-2 showed no signs of damage. Fluences of 5 × 1023 He-m-2 and higher showed significant helium-cluster formation within the first 30 nm, with positron lifetimes in the vicinity 0.5-0.6 ns. The sample temperature was significantly higher for these higher fluence exposures (∼400 K) due to plasma heating. This higher temperature likely enhanced bubble formation by significantly increasing the rate interstitial helium clusters generate vacancies, which is we suspect is the rate-limiting step for helium-vacancy cluster/bubble nucleation in the absence of pre-existing defects.The authors are grateful to the technical assistance within the Australian Plasma Fusion Research Facility that is partly funded by the Australian Government under the Super Science Initiative, financed from the Education Investment Fund. GISAXS research was undertaken on the SAXS/WAXS beamline at the Australian Synchrotron, part of ANSTO. We gratefully acknowledge beamline scientists at the Australian Synchrotron for their assistance. PK acknowledges the Australian Research Council for financial support

Sustainability Initiatives in East Bayside Neighborhood Portland, Maine

This is a bundle containing research on sustainability initiatives that could be implemented in the East Bayside neighborhood of Portland, ME. These six essays were prepared by the Spring, 2010 Sustainable Communities Class known as CPD 602 at the University of Southern Maine. The class is part of the core curriculum of the Community Planning and Development program of the Muskie School of Public Service at the university. The instructor for the class was Samuel Merrill, Ph. D. who is also director of the New England Environmental Finance Center at the University. These papers were prepared in conjunction with Alan Holt, an architect and instructor at USM who coordinated work being done in the East Bayside neighborhood by a Sustainable Design Assessment Team (SDAT) funded by the American Institute of Architects (AIA). This work is an academic exercise, and while some aspects of these recommendations may be implemented please note that this is not an official planning document. Rather, these ideas merit public scrutiny and the full democratic public participation process before they can proceed further

Interventions for increasing colorectal cancer screening uptake among African-American men: a systematic review and meta-analysis

This is a protocol of a systematic review