The role of mental health counseling in college students' academic success: An interrupted time series analysis.

Retention remains a problem for postsecondary institutions and college students. To address these issues, researchers have sought to identify factors of college success and retention. Findings have consistently shown the importance of psychosocial factors and mental health on college students' academic success. As such, university and college counseling centers are well positioned to enhance students' academic success by addressing psychosocial distress. However, existing literature on the effect of counseling on college students' academic success is mixed, and limitations exist. To address previous limitations of the literature, this study utilized an interrupted time series design to examine differences in students' postcounseling academic success compared to their precounseling academic success. Additionally, we examined the association between changes in students' psychological distress and academic distress for students who endorsed clinical distress at the onset of counseling and changes in their grade point average (GPA) over time. Data for this study consisted of 1,231 clients seen by 49 therapists at a university counseling center. As hypothesized, students' GPAs increased at a greater rate postcounseling compared to precounseling. Additionally, for students who were clinically distressed at the onset of counseling, reductions in their psychological distress were associated with positive changes in their GPA over time, but the relationship between changes in their academic distress and changes in their GPA was not significant. This study suggests that counseling can be beneficial for college students' academic success, in part due to changes in students' psychological distress, but not their academic distress, specifically for clinically distressed students. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Electrochemical Detection of Single Phospholipid Vesicle Collisions at a Pt Ultramicroelectrode.

We report the collision behavior of single unilamellar vesicles, composed of a bilayer lipid membrane (BLM), on a platinum (Pt) ultramicroelectrode (UME) by two electrochemical detection methods. In the first method, the blocking of a solution redox reaction, induced by the single vesicle adsorption on the Pt UME, can be observed in the amperometric i-t response as current steps during the electrochemical oxidation of ferrocyanide. In the second technique, the ferrocyanide redox probe is directly encapsulated inside vesicles and can be oxidized during the vesicle collision on the UME if the potential is poised positive enough for ferrocyanide oxidation to occur. In the amperometric i-t response for the latter experiment, a current spike is observed. Here, we report the vesicle blocking (VB) method as a relevant technique for determining the vesicle solution concentration from the collisional frequency and also for observing the vesicle adhesion on the Pt surface. In addition, vesicle reactor (VR) experiments show clear evidence that the lipid bilayer membrane does not collapse or break open at the Pt UME during the vesicle collision. Because the bilayer is too thick for electron tunneling to occur readily, an appropriate concentration of a surfactant, such as Triton X-100 (TX100), was added in the VR solution to induce loosening of the bilayer (transfection conditions), allowing the electrode to oxidize the contents of the vesicle. With this technique, the TX100 effect on the vesicle lipid bilayer permeability can be evaluated through the current spike charge and frequency corresponding to redox vesicle collisions.

Food insecurity is associated with lower diet quality among dental students.

PURPOSE: Food insecurity is associated with lower diet quality, adverse health outcomes, and academic difficulty among undergraduate students. The objective was to identify the relationship between food security status and diet quality in dental students. METHODS: All dental students attending Howard University (n = 286) or the University of Iowa (n = 326) during the fall 2021 semester were invited to complete a cross-sectional survey designed to query demographics, food security status (i.e., United States Department of Agriculture's ten item Adult Food Security Module), and diet quality (i.e., short Healthy Eating Index). The survey was administered using the Qualtrics platform. RESULTS: Response rates were similar for Howard (32.5%) and Iowa (29.4%). Students with food insecurity (46.0%) were slightly older and more likely to be Black or other, first generation professional/graduate students, and receive financial aid than peers with food security (p < 0.050). Food insecurity was associated with lower intakes of fruits and vegetables (p ≤ 0.005), higher intakes of added sugars (p < 0.001), and lower diet quality (p = 0.003). In linear regression analyses that controlled for other variables, food insecurity (p = 0.012), school site (p = 0.027), and gender (p = 0.039) were predictive of lower diet quality. CONCLUSIONS: The inability to procure adequate and appropriate foods was associated with marginal dietary habits (i.e., less than ideal food choices and eating behaviors) and lower diet quality in dental students. Both marginal dietary habits and lower diet quality increase chronic disease risk and may present a barrier to academic success. Addressing food insecurity among dental students is necessary to ensure equitable opportunities for a healthy workforce in the future.

Is food insecurity a barrier to dental student success?

PURPOSE: The prevalence of food insecurity among undergraduate students is higher than the national average and associated with adverse academic outcomes. Our objective was to describe the prevalence of food insecurity, food access behaviors, and associations between food security status and well-being in a dental student population. METHODS: All dental students (N = 328) enrolled in the College of Dentistry at the University of Iowa in the fall 2019 semester were invited to participate. The survey was designed to query demographic variables, food security status (i.e., the United States Department of Agriculture's 10-item Adult Food Security Module), and food- or hunger-related well-being (i.e., sleep, academic performance, and stress). The survey was administered using the Qualtrics survey platform. Following the initial invitation, students were sent two reminders and allowed 3 weeks for completion. RESULTS: The survey response rate was 24.7%. Forty-seven percent of respondents were food insecure. Food insecure students were more likely to attend collegiate programming (e.g., lunch and learns) for the primary purpose of obtaining free food than their food secure peers (p <0.001). In addition, food insecure students were more likely to report experiencing food- or hunger-related sleep (p = 0.001), study or academic performance (p <0.001), or stress difficulties than their food secure peers (p <0.001). CONCLUSION: The prevalence of food insecurity in dental students was relatively high and associated with adverse food- and/or hunger-related well-being outcomes. Food insecurity might be a barrier to dental student success, compromising their immediate health and ability to learn.

Preferential Equilibrium Partitioning of Positively Charged Tryptophan into Phosphatidylcholine Bilayer Membranes.

The interactions between small molecules and lipid bilayers play a critical role in the function of cellular membranes. Understanding how a small molecule interacts with the lipid bilayer differently based on its charge reveals primordial mechanisms of transport across membranes and assists in the design of drug molecules that can penetrate cells. We have previously reported that tryptophan permeated through a phosphatidylcholine lipid bilayer membrane at a faster rate when it was positively charged (Trp+) than when negatively charged (Trp-), which corresponded to a lower potential of mean force (PMF) barrier determined through simulations. In this report, we demonstrate that Trp+ partitions into the lipid bilayer membrane to a greater degree than Trp- by interacting with the ester linkage of a phosphatidylcholine lipid, where it is stabilized by the electron withdrawing glycerol functional group. These results are in agreement with tryptophan's known role as an anchor for transmembrane proteins, though the tendency for binding of a positively charged tryptophan is surprising. We discuss the implications of our results on the mechanisms of unassisted permeation and penetration of small molecules within and across lipid bilayer membranes based on molecular charge, shape, and molecular interactions within the bilayer structure.

Defect-Assisted Permeation Through a Phospholipid Membrane: Experimental and Computational Study of the Peptide WKW.

We investigate membrane permeation by the peptide WKW that is amidated at its C-terminus and therefore carries a positive charge of +2. To facilitate an efficient calculation, we introduce a novel set of simple coarse variables that measure permeation depth and membrane distortion. The phospholipid head groups shift toward the center of the membrane, following the permeating peptide, and create a defect that assists permeation. The Milestoning algorithm was used in the new coarse space to compute the free-energy profile and the mean first passage time. The barrier was lower than expected from a simple continuum estimate. This behavior is consistent with the known behavior of positively charged cell-penetrating peptides, and is explained by a detailed mechanism of defect formation and propagation revealed by the simulations.

Partition of Positively and Negatively Charged Tryptophan Ions in Membranes with Inverted Phospholipid Heads: Simulations and Experiments.

A joint experimental and computational study illustrates that the partitioning of positively and negatively charged tryptophan in a phospholipid bilayer is significantly altered by a reversal in the head group dipole arrangement. Experiments were conducted using tryptophan as a fluorescent reporter of its local environment. Based on the experimental design in a recent publication ( Anderson , C. M. ; Cardenas , A. ; Elber , R. ; Webb , L. J. J. Phys. Chem. B 2018 , 123 , 170 - 179 ), we were able to determine that the arrangement of the head group dipole altered the degree of partitioning of charged tryptophan in the lipid bilayer. In parallel, atomically detailed simulations were performed for the two membrane systems. The simulation results are in accord with the experimental findings and support a simple molecular partition mechanism of electrostatic interactions with the head groups, glycerol linkers, and interfacial water dipoles.

Direct Measurement of the Effect of Cholesterol and 6-Ketocholestanol on the Membrane Dipole Electric Field Using Vibrational Stark Effect Spectroscopy Coupled with Molecular Dynamics Simulations.

Biological membranes are heterogeneous structures with complex electrostatic profiles arising from lipids, sterols, membrane proteins, and water molecules. We investigated the effect of cholesterol and its derivative 6-ketocholestanol (6-kc) on membrane electrostatics by directly measuring the dipole electric field (F⃗d) within lipid bilayers containing cholesterol or 6-kc at concentrations of 0-40 mol% through the vibrational Stark effect (VSE). We found that adding low concentrations of cholesterol, up to ∼10 mol %, increases F⃗d, while adding more cholesterol up to 40 mol% lowers F⃗d. In contrast, we measured a monotonic increase in F⃗d as 6-kc concentration increased. We propose that this membrane electric field is affected by multiple factors: the polarity of the sterol molecules, the reorientation of the phospholipid dipole due to sterol, and the impact of the sterol on hydrogen bonding with surface water. We used molecular dynamics simulations to examine the distribution of phospholipids, sterol, and helix in bilayers containing these sterols. At low concentrations, we observed clustering of sterols near the vibrational probe whereas at high concentrations, we observed spatial correlation between the positions of the sterol molecules. This work demonstrates how a one-atom difference in a sterol changes the physicochemical and electric field properties of the bilayer.