Here Today, Gone Tomorrow: Understanding Freshman Attrition Using Person-Environment Fit Theory

Person-Environment (PE) fit theory was used to explore the relationship between student involvement and freshman retention. Incoming freshmen (N=382) were followed longitudinally in a twowave panel study, the summer before beginning college, and again during the spring of their freshman year. Involvement levels, a variety of summer and spring preferences (Ps), and spring perceptions (Es) regarding specific aspects of their college environment were assessed. Twelve PE fit indicators were derived and compared with respect to their relationship with student involvement and retention. Results indicated that involvement was linked to some PE fit indicators. Traditional parametric statistical analyses were compared with a new, nonparametric technique, Classification Tree Analysis (CTA), to identify the most accurate classification model for use in designing potential attrition interventions. Discriminant analysis was 14% more accurate than CTA in classifying returners (97% vs. 85%), but CTA was 962% more accurate classifying dropouts (8% vs. 84%). CTA identified nine clusters— five of returners and four of dropouts, revealing that different subgroups of freshmen chose to return (and stay) for different reasons. Students’ end-of-the-year preferences appear to be more important than anticipated preferences, college perceptions, or PE fit level

Cross-linking of Nitrogenase Components: Structure and Activity of the Covalent Complex

The nitrogenase complex from Azotobacter vinelandii is composed of the MoFe protein (Av1), an α_2β_2 tetramer, and the Fe protein (Av2), a γ_2 dimer. During turnover of the enzyme, electrons are transferred from Av2 to Av1 in parallel with the hydrolysis of MgATP. Using the cross-linking reagent, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide, we have identified some of the properties of the complex between the two components. The cross-linking reaction was highly specific yielding a single apparent M_r = 97,000 protein. The amount of cross-linked product was essentially independent of whether MgATP or MgADP were in the reaction. Also, the amount was maximum at high ratios of Av2 to Av1. The M_r = 97,000 protein was characterized by amino acid analysis and Edman degradation and was found to be consistent with a 1:1 complex of an Av2 γ subunit and an Av1 β subunit (the amino terminal serine subunit). The complex was no longer active in the nitrogenase reaction which supports, but does not prove, the requirement for dissociation of the complex after each electron transferred. Nitrogenase activity and cross-linking were inhibited in an identical way by NaCl, which suggests that electrostatic forces are critical to the formation of the electron transfer complex

Effects of Hurricane Bret on Northern Bobwhite Survival in South Texas

The impacts of intense storms such as hurricanes on wildlife rarely are documented. We had the opportunity to monitor the impact of Hurricane Bret on northern bobwhite (Colinus virginianus) survival and reproduction in Brooks County, Texas. On 22 August 1999, Hurricane Bret struck our study area, which received \u3e 45 cm of rain and experienced wind gusts \u3e160 km/h. We documented the survival of bobwhite adults (n = 82), broods (n = 15), and nests (n = 4) via radiotelemetry before and after the hurricane. Only 11 (13%) adult bobwhites were killed, with 4 killed directly from exposure to the hurricane. Broods experienced higher mortality, with 7 (47%) broods killed during the hurricane. Six of the 7 dead broods were \u3c 1 week old. Sizes of the 8 surviving broods were reduced from a mean brood size of about 11 chicks prior to the hurricane to a mean size of 4 after the hurricane (P = 0.01). Of the 4 nests monitored, 3 were depredated and eggs in 1 nest hatched the weekend of the storm. Hurricanes may negatively impact the survival of young (i.e., \u3c 2 weeks old) bobwhite broods

Forward Promise: Disrupting Dehumanization and Affirming the Humanity of BYMOC and Their Villages

Dehumanization is the cause of generations of historical trauma. The cycle begins with negative narratives that label people of color—particularly boys and young men—violent, criminal, and animalistic. To combat the perceived threat, dangerous actions are taken by the majority culture and systems which further dehumanize BYMOC. As a result, BYMOC and their villages often hold harmful internal feelings of unworthiness taught by their oppressors. It is not uncommon for them to engage in various forms of self-harm or to harm others. These destructive external reactions are not explained as normal responses to trauma. Stories of their negative reactions become justification for more negative narratives and the cycle begins agai

Crystallization of Azotobacter vinelandii Nitrogenase Iron Protein

The iron protein from Azotobacter vinelandii nitrogenase has been crystallized in the reduced form. The needle-shaped crystals are in space group P2_12_12 (a = 94.6 Å, b = 179.9 Å, c = 74.1 Å) and diffract to at least 3.5-Å resolution. Five or six Fe-protein monomers are present in the asymmetric unit

Perioperative gait analysis after total hip arthroplasty: Does outpatient surgery compromise patient outcomes?

Background: There has been a continuing trend towards decreasing the length of hospital stay for patients undergoing total hip arthroplasty (THA). Outpatient procedures, discharging patients on the same day as surgery, have now become possible yet little research has been done to examine the impact this might have on patients during early recovery. We aimed to investigate the impact of discharge time on gait and patient-reported outcomes in the early post-operative period. Methods: We measured gait velocity, stride length, single-limb support and single-limb support symmetry preoperatively, at discharge from the hospital, and two-, six- and 12-weeks postoperatively. Participants also completed the Timed Up and Go and a series of questionnaires (WOMAC, SF-12, Harris Hip Score and pain VAS) at each visit. Results: Thirty-six participants undergoing a direct anterior THA with a single surgeon were enrolled in this study. Sixteen participants were discharged on the same day as surgery (outpatient group), while 20 stayed at least one night in hospital (inpatient group). We found pain at time of discharge to be significantly lower in the outpatient group compared to the inpatient group (p=0.04). We found no other differences between the groups for any gait, patient-reported or surgical outcomes (p\u3c0.05). Conclusion: Following a direct anterior total hip arthroplasty, patients who stayed overnight had significantly more pain at discharge than those discharged as outpatients. There were no differences in gait or patient-reported outcomes between groups. Interdisciplinary Reflection: This study incorporates aspects of kinesiology, surgery, rehabilitation and health policy

Implementation of outpatient total joint arthroplasty in canada: Where we are and where we need to go

© 2020 Zomar et al. Total joint arthroplasties (TJA) are successful procedures for the treatment of end-stage hip and knee arthritis. Length of stay in hospitals after these procedures has been steadily decreasing over time, with outpatient procedures (discharge on the same day as surgery) introduced in the US within the last 20 years. Reducing length of stay after TJA can provide cost savings. Centres in Canada have started to utilize outpatient TJA procedures, but we have identified some barriers that may have limited their implementation. We have summarized the current literature for outpatient TJA and discussed potential solutions for the current barriers